85 results on '"Chan JYH"'
Search Results
2. Hybrid Convolutional Neural Network Ensemble for Activity Recognition in Mobile Phones
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Chan, Jyh-Huah, primary, Lim, Hui-Juin, additional, Hoang, Ngoc-Son, additional, Lim, Jeong-Hoon, additional, Nguyen, Khang, additional, Nguyen, Binh P., additional, Chui, Chee-Kong, additional, and Chua, Matthew Chin-Heng, additional
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- 2020
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3. Amelioration of central cardiovascular regulatory dysfunction by tropomyocin receptor kinase B in a mevinphos intoxication model of brain stem death
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Chan, SHH, Chan, JYH, Hsu, KS, Li, FCH, Sun, EYH, Chen, WL, and Chang, AYW
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Male ,Brain Death ,Microinjections ,Blotting, Western ,Enzyme-Linked Immunosorbent Assay ,Research Papers ,Cardiovascular System ,Rats ,Enzyme Activation ,Rats, Sprague-Dawley ,Animals ,Mevinphos ,Receptor, trkB ,Cholinesterase Inhibitors ,Phosphorylation - Abstract
Little information exists on the mechanisms that precipitate brain stem death, the legal definition of death in many developed countries. We investigated the role of tropomyocin receptor kinase B (TrkB) and its downstream signalling pathways in the rostral ventrolateral medulla (RVLM) during experimental brain stem death.An experimental model of brain stem death that employed microinjection of the organophosphate insecticide mevinphos bilaterally into the RVLM of Sprague-Dawley rats was used, in conjunction with cardiovascular, pharmacological and biochemical evaluations.A significant increase in TrkB protein, phosphorylation of TrkB at Tyr(516) (pTrkB(Y516) ), Shc at Tyr(317) (pShc(Y317) ) or ERK at Thr(202) /Tyr(204) , or Ras activity in RVLM occurred preferentially during the pro-life phase of experimental brain stem death. Microinjection bilaterally into RVLM of a specific TrkB inhibitor, K252a, antagonized those increases. Pretreatment with anti-pShc(Y317) antiserum, Src homology 3 binding peptide (Grb2/SOS inhibitor), farnesylthioacetic acid (Ras inhibitor), manumycin A (Ras inhibitor) or GW5074 (Raf-1 inhibitor) blunted the preferential augmentation of Ras activity or ERK phosphorylation in RVLM and blocked the up-regulated NOS I/protein kinase G (PKG) signalling, the pro-life cascade that sustains central cardiovascular regulation during experimental brain stem death.Activation of TrkB, followed by recruitment of Shc/Grb2/SOS adaptor proteins, leading to activation of Ras/Raf-1/ERK signalling pathway plays a crucial role in ameliorating central cardiovascular regulatory dysfunction via up-regulation of NOS I/PKG signalling cascade in the RVLM in brain stem death. These findings provide novel information for developing therapeutic strategies against this fatal eventuality.
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- 2011
4. Amelioration of central cardiovascular regulatory dysfunction by tropomyocin receptor kinase B in a mevinphos intoxication model of brain stem death
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Chan, SHH, primary, Chan, JYH, additional, Hsu, KS, additional, Li, FCH, additional, Sun, EYH, additional, Chen, WL, additional, and Chang, AYW, additional
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- 2011
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5. BRE (brain and reproductive organ-expressed (TNFRSF1A modulator))
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Chui, YL, primary, Lee, KKH, additional, and Chan, JYH, additional
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- 2011
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6. Locus coeruleus control of spinal motor output
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Fung, Sj, Manzoni, Diego, and Chan JYH Barnes CD
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- 1991
7. Development of an air combat evaluation system
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Lan, C., primary, Chan, Jyh-Jang, additional, and Ho, Jyh-Yeuan, additional
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- 2000
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8. Numerical investigation of supersonic mixed-compression inlet using an implicit upwind scheme
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Chan, Jyh-Jang, primary and Liang, Shen-Min, additional
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- 1992
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9. An improved upwind scheme for the euler equations
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Liang, Shen-Min, primary and Chan, Jyh-Jang, additional
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- 1989
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10. Brain Amyloid-β Peptide Is Associated with Pain Intensity and Cognitive Dysfunction in Osteoarthritic Patients.
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Wen CH, Kang HY, and Chan JYH
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- Humans, Female, Male, Aged, Middle Aged, Prospective Studies, Alzheimer Disease cerebrospinal fluid, Alzheimer Disease blood, Pain Measurement, Osteoarthritis cerebrospinal fluid, Osteoarthritis complications, Osteoarthritis blood, Cytokines cerebrospinal fluid, Cytokines blood, Brain metabolism, Brain diagnostic imaging, Osteoarthritis, Knee cerebrospinal fluid, Osteoarthritis, Knee complications, Osteoarthritis, Knee blood, Amyloid beta-Peptides cerebrospinal fluid, Amyloid beta-Peptides blood, Biomarkers blood, Biomarkers cerebrospinal fluid, Cognitive Dysfunction cerebrospinal fluid, Cognitive Dysfunction etiology, Cognitive Dysfunction blood, Pain cerebrospinal fluid, Pain etiology
- Abstract
Considerable studies have demonstrated that osteoarthritis (OA) is a risk factor for dementia. The precise mechanisms underlying the association between OA and increased risk for cognitive dysfunction, however, remain unclear. This study aimed at exploring the associations between pro-inflammatory cytokines/chemokines, biomarkers of Alzheimer's disease (AD), pain intensity, and cognitive decline in knee joint OA patients. A total of 50 patients (26 in OA group and 24 in non-OA control group) were enrolled in this prospective, observational study. The visual analogue scale (VAS) score for pain intensity and Cognitive Abilities Screening Instrument (CASI) score for cognitive functions were examined in both groups. The plasma and cerebrospinal fluid (CSF) levels of pro-inflammatory molecules (IL-1β, IL-6, TNF-α, fractalkine, BDNF, MCP-1, and TGF-β), as well as biomarkers of AD (Aβ
40 , Aβ42 , total-tau, and phospho-tau), were measured by multiplex immunoassay. Correlations among plasma or CSF biomarkers and questionnaire scores were assessed using Pearson's correlation coefficient and simple linear regressions. There were more patients in the OA group whose CASI cutoff percentiles were40 , and Aβ 42 in CSF of OA patients. The CSF levels of Aβ40 and Aβ42 in OA patients were negatively correlated with attention and abstract scores in CASI. The findings of this study suggest that knee OA is associated with poor cognitive performance, and this association is particularly pronounced in OA patients with chronic pain. Higher levels of brain AD biomarkers, such as Aβ40 and Aβ42 , may partially mediate this relationship.- Published
- 2024
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11. Case - Emergent management of severe penile and scrotal edema due to prolonged metallic ring entrapment.
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Berjaoui MB, Nguyen DD, Al-Daqqaq Z, Chan JYH, and Krakowsky Y
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- 2024
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12. Fractional CO 2 laser for the treatment of Peyronie's disease: A pilot clinical trial.
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Chan JYH, Alhamam A, Witherspoon L, Rivers JK, and Flannigan RK
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- 2024
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13. Effect of Purified Resveratrol Butyrate Ester Monomers against Hypertension after Maternal High-Fructose Intake in Adult Offspring.
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Tain YL, Hou CY, Tzeng HT, Lin SF, Chang-Chien GP, Lee WC, Wu KLH, Yu HR, Chan JYH, and Hsu CN
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- Animals, Female, Pregnancy, Rats, Antioxidants pharmacology, Male, Butyrates, Gastrointestinal Microbiome drug effects, Lactation, Nitric Oxide metabolism, Fructose, Rats, Sprague-Dawley, Hypertension prevention & control, Hypertension etiology, Resveratrol pharmacology, Prenatal Exposure Delayed Effects, Maternal Nutritional Physiological Phenomena, Dietary Supplements
- Abstract
Background: Offspring hypertension arising from adverse maternal conditions can be mitigated through dietary nutritional supplementation, including resveratrol. Previously, we identified derivatives of resveratrol butyrate ester (RBE), specifically 3,4'-di-O-butanoylresveratrol (ED2) and 3-O-butanoylresveratrol (ED4), demonstrating their superior antioxidant capabilities compared to RBE itself. This study sought to assess the protective impact of maternal supplementation with ED2 or ED4 on offspring hypertension in a rat model subjected to a high-fructose (HF) diet during pregnancy and lactation., Methods: Female Sprague-Dawley rats were distributed into distinct dietary groups throughout pregnancy and lactation: (1) standard chow; (2) HF diet (60%); (3) HF diet supplemented with ED2 (25 mg/L); and (4) HF diet supplemented with ED4 (25 mg/L). Male offspring were euthanized at the age of 12 weeks., Results: The maternal HF diet induced hypertension in the offspring, which was mitigated by perinatal supplementation with either ED2 or ED4. These protective effects were attributed to the antioxidant properties of ED2 and ED4, resulting in an increased availability of nitric oxide (NO). Additionally, supplementation with ED2 was connected to an increased abundance of Bifidobacterium and Clostridium genera, which was accompanied by a decrease in Angelakisella and Christensenella . On the other hand, ED4 supplementation shielded rat offspring from hypertension by elevating concentrations of short-chain fatty acids (SCFAs) and their receptors while reducing trimethylamine- N -oxide (TMAO) levels., Conclusions: These findings highlight the potential of purified RBE monomers, ED2 and ED4, as preventive measures against hypertension resulting from a maternal high-fructose diet. Further research is warranted to explore their clinical applications based on these promising results.
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- 2024
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14. The Ability of Physical Performance Measures to Identify Fall Risk in Older Adults Living With Dementia: A Systematic Review and Meta-Analysis.
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Chan WLS, Pin TW, Chan JYH, Siu GCH, and Tsang SMH
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- Humans, Aged, Risk Assessment, Aged, 80 and over, Postural Balance physiology, Male, Geriatric Assessment methods, Female, Accidental Falls, Dementia, Physical Functional Performance
- Abstract
Objectives: To determine whether physical performance measures commonly used in clinical settings can discriminate fallers from nonfallers and predict falls in older adults with dementia., Design: Systematic review and meta-analysis., Setting and Participants: Older adults with dementia residing in the community, hospitals, and residential care facilities., Methods: MEDLINE, Embase, PsycINFO, CINAHL, SPORTDiscus, the Cochrane Library, and the PEDro databases were searched from inception until December 27, 2023 (PROSPERO registration number: CRD42022303670). Retrospective or prospective studies that evaluated the associations between physical performance measures and falls in older adults with dementia were included. A random effects model was used to calculate the standardized mean difference (SMD) and 95% CI for each physical performance measure between fallers and nonfallers. Sensitivity analyses were conducted on the longitudinal studies to determine the ability of physical performance measures to predict future falls., Results: Twenty-eight studies were included in this review (n = 3542). The 5-time chair stand test [SMD = 0.23 (0.01, 0.45)], the Berg Balance Scale [SMD = -0.52 (-0.87, -0.17)], postural sway when standing on the floor [SMD = 0.25 (0.07, 0.43)] and on a foam surface [SMD = 0.45 (0.25, 0.66)], and the Short Physical Performance Battery total score [SMD = -0.46 (-0.66, -0.27)] could discriminate fallers from nonfallers. Sensitivity analyses showed that gait speed could predict future falls in longitudinal cohort studies [SMD = -0.29 (-0.49, -0.08)]. Subgroup analyses showed that gait speed [SMD = -0.21 (-0.38, -0.05)] and the Timed Up and Go test [SMD = 0.54 (0.16, 0.92)] could identify fallers staying in residential care facilities or hospitals., Conclusions and Implications: The 5-time chair stand test, the Berg Balance Scale, postural sway when standing on the floor and a foam surface, and the Short Physical Performance Battery can be used to predict falls in older adults with dementia. Gait speed and the Timed Up and Go test can be used to predict falls in institutionalized older adults with dementia. Clinicians are recommended to use these physical performance measures to assess fall risk in older adults with dementia., Competing Interests: Disclosures The authors declare no conflicts of interest., (Copyright © 2024 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.)
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- 2024
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15. The Hong Kong Renal Registry: a recent update.
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Chan JYH, Cheng YL, Yuen SK, Wong PN, Cheng HM, Mo KL, Yung CY, Chow KM, Fung SKS, Chak WL, Ma MKM, Ho TL, Lee A, Wong S, Cheung SF, Ma ALT, Szeto CC, Tang SCW, and Lui SL
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- Hong Kong epidemiology, Humans, Kidney Diseases epidemiology, Registries
- Abstract
Competing Interests: All authors have disclosed no conflicts of interest.
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- 2024
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16. Feasibility of using a combination of staphylococcal superantigen-like proteins 3, 7 and 11 in a fusion vaccine for Staphylococcus aureus.
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Chan JYH, Clow F, Pearson V, Langley RJ, Fraser JD, and Radcliff FJ
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- Animals, Mice, Antibodies, Bacterial immunology, Antibodies, Bacterial blood, Female, Recombinant Fusion Proteins immunology, Immunoglobulin G immunology, Immunoglobulin G blood, Feasibility Studies, Vaccination, Antigens, Bacterial immunology, Mice, Inbred BALB C, Adjuvants, Immunologic, Staphylococcus aureus immunology, Staphylococcal Vaccines immunology, Superantigens immunology, Staphylococcal Infections immunology, Staphylococcal Infections prevention & control, Bacterial Proteins immunology
- Abstract
Staphylococcus aureus is a significant bacterial pathogen in both community and hospital settings, and the escalation of antimicrobial-resistant strains is of immense global concern. Vaccination is an inviting long-term strategy to curb staphylococcal disease, but identification of an effective vaccine has proved to be challenging. Three well-characterized, ubiquitous, secreted immune evasion factors from the staphylococcal superantigen-like (SSL) protein family were selected for the development of a vaccine. Wild-type SSL3, 7 and 11, which inhibit signaling through Toll-like receptor 2, cleavage of complement component 5 and neutrophil function, respectively, were successfully combined into a stable, active fusion protein (PolySSL7311). Vaccination of mice with an attenuated form of the PolySSL7311 protein stimulated significantly elevated specific immunoglobulin G and splenocyte proliferation responses to each component relative to adjuvant-only controls. Vaccination with PolySSL7311, but not a mixture of the individual proteins, led to a > 10
2 reduction in S. aureus tissue burden compared with controls after peritoneal challenge. Comparable antibody responses were elicited after coadministration of the vaccine in either AddaVax (an analog of MF59) or an Alum-based adjuvant; but only AddaVax conferred a significant reduction in bacterial load, aligning with other studies that suggest both cellular and humoral immune responses are necessary for protective immunity to S. aureus. Anti-sera from mice immunized with PolySSL7311, but not individual proteins, partially neutralized the functional activities of SSL7. This study confirms the importance of these SSLs for the survival of S. aureus in vivo and suggests that PolySSL7311 is a promising vaccine candidate., (© 2024 The Authors. Immunology & Cell Biology published by John Wiley & Sons Australia, Ltd on behalf of the Australian and New Zealand Society for Immunology, Inc.)- Published
- 2024
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17. Carbohydrate-Mediated Pregnancy Gut Microbiota and Neonatal Low Birth Weight.
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Yu HR, Yeh YT, Tzeng HT, Dai HY, Lee WC, Wu KLH, Chan JYH, Tain YL, and Hsu CN
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- Humans, Female, Pregnancy, Infant, Newborn, Adult, Prospective Studies, Maternal Nutritional Physiological Phenomena, Taiwan, RNA, Ribosomal, 16S genetics, Fetal Development, Gastrointestinal Microbiome drug effects, Infant, Low Birth Weight, Dietary Carbohydrates, Feces microbiology
- Abstract
The effects of gut microbiota on the association between carbohydrate intake during pregnancy and neonatal low birth weight (LBW) were investigated. A prospective cohort study was conducted with 257 singleton-born mother-child pairs in Taiwan, and maternal dietary intake was estimated using a questionnaire, with each macronutrient being classified as low, medium, or high. Maternal fecal samples were collected between 24 and 28 weeks of gestation, and gut microbiota composition and diversity were profiled using 16S rRNA amplicon gene sequencing. Carbohydrates were the major source of total energy (56.61%), followed by fat (27.92%) and protein (15.46%). The rate of infant LBW was 7.8%, which was positively correlated with maternal carbohydrate intake. In the pregnancy gut microbiota, Bacteroides ovatus and Dorea spp. were indirectly and directly negatively associated with fetal growth, respectively; Rosenburia faecis was directly positively associated with neonatal birth weight. Maternal hypertension during pregnancy altered the microbiota features and was associated with poor fetal growth. Microbiota-accessible carbohydrates can modify the composition and function of the pregnancy gut microbiota, thus providing a potential marker to modulate deviations from dietary patterns, particularly in women at risk of hypertension during pregnancy, to prevent neonatal LBW.
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- 2024
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18. CD, or not CD, that is the question: a digital interobserver agreement study in coeliac disease.
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Denholm J, Schreiber BA, Jaeckle F, Wicks MN, Benbow EW, Bracey TS, Chan JYH, Farkas L, Fryer E, Gopalakrishnan K, Hughes CA, Kirkwood KJ, Langman G, Mahler-Araujo B, McMahon RFT, Myint KW, Natu S, Robinson A, Sanduka A, Sheppard KA, Tsang YW, Arends MJ, and Soilleux EJ
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- Humans, Transglutaminases, Artificial Intelligence, Observer Variation, Immunoglobulin A, Celiac Disease diagnosis
- Abstract
Objective: Coeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis., Design: We undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data., Results: We found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen's kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen's kappa coefficient of 0.67 (±0.09)., Conclusion: We showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence., Competing Interests: Competing interests: ES and MS are shareholders in Lyzeum Ltd, by whom JD was employed at the time of this work., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2024
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19. Reactive postural adjustment in response to predictable and unpredictable perturbations in healthy adults: A comparison between swayback, hyperlordotic and erect postures.
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Tsang SMH, Chan EHW, Chan JYH, Huang GPY, Lam KKT, Lam EWY, Fu ACL, and Sun ER
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- Adult, Sheep, Animals, Humans, Muscle, Skeletal physiology, Posture physiology, Lumbar Vertebrae, Electromyography, Swayback, Lordosis
- Abstract
Background: Promoting an erect posture in standing has been advocated to offer superior protection to the spine when compared to hyperlordotic and swayback postures., Research Question: Do postural adjustments towards external perturbation differ between erect, hyperlordotic and swayback postures? If so, which posture offers better protection to lumbar spine?, Methods: Forty-four healthy adults received top-down perturbations under unpredictable (without visual-and-auditory input) and predictable (with visual-and-auditory input) conditions in three simulated postures: erect, hyperlordotic, and swayback. Postural adjustments namely the centre of pressure parameters, joint angle onsets, and neuromuscular responses measured by muscle onsets and co-contraction between muscle pairs upon the perturbation were compared using the two-way repeated measures ANOVA. Post-hoc analysis with Bonferroni correction was conducted to identify the between-posture differences for the respective postural adjustment parameters., Results: Path length, ellipse area and average velocity of centre of pressure were significantly greater under unpredictable condition as compared to predictable condition (p < 0.001). Significant between-posture difference was detected in centre of pressure path length (p < 0.035), pelvic tilt onset (p < 0.038) and all muscle co-contraction indexes (p < 0.001). Post-hoc analysis revealed significantly smaller centre of pressure path length in erect posture as compared to hyperlordotic and swayback postures (p < 0.01) under unpredictable conditions. Significantly greater co-contraction indexes of lumbar multifidus and erector spinae, and internal oblique and lumbar multifidus were found in hyperlordotic as compared to erect and swayback postures (p < 0.05)., Significance: Compared to erect posture, adoption of hyperlordotic and swayback postures altered the contributions of the active and passive subsystems of the spine that regulates postural control upon external perturbations. Such differences in neuromuscular control may lessen the capacity of the human spine to withstand loading and shear forces. Prospective studies are required to validate if habitually adopted hyperlordotic and swayback postures contribute to an earlier/ higher prevalence of spinal dysfunctions., Competing Interests: Declaration of Competing Interest We write to confirm that there are no known conflicts of interest associated with this publication and there has been no financial support for this work that could have influenced its outcome., (Copyright © 2023 Elsevier B.V. All rights reserved.)
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- 2024
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20. A quantitative analysis of voiding cystourethrogram features confirms the association between high-grade vesicoureteral reflux with male sex, younger age, and hydronephrosis.
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Khondker A, Kwong JCC, Yadav P, Chan JYH, Singh A, Erdman L, Keefe DT, Rickard M, and Lorenzo AJ
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Introduction: Vesicoureteral reflux (VUR) is commonly diagnosed in the workup of urinary tract infections or hydronephrosis in children. Traditionally, VUR severity is graded subjectively based on voiding cystourethrogram (VCUG) imaging. Herein, we characterized the association between age, sex, and indication for VCUG, by employing standardized quantitative features., Methods: We included renal units with a high certainty in VUR grade (>80% consensus) from the qVUR model validation study at our institution between 2013 and 2019. We abstracted the following variables: age, sex, laterality, indication for VCUG, and qVUR parameters (tortuosity, ureter widths on VCUG). High-grade VUR was defined as grade 4 or 5 The association between each variable and VUR grade was assessed., Results: A total of 443 patients (523 renal units) were included, consisting of a 48:52 male/female ratio. The median age at VCUG was 13 months. Younger age at VCUG (<6 months) was associated with greater odds of severe VUR (odds ratio [OR] 2.0), and there was a weak correlation between age and VUR grade (ρ=-0.17). Male sex was associated with increased odds of high-grade VUR (OR 2.7). VCUGs indicated for hydronephrosis were associated with high-grade VUR (OR 4.1) compared to those indicated for UTI only. Ureter tortuosity and width were significantly associated with each clinical variable and VUR severity., Conclusions: Male sex, younger age (<6 months), and history of hydronephrosis are associated with both high-grade VUR and standardized quantitative measures, including greater ureter tortuosity and increased ureteral width. This lends support to quantitative assessment to improve reliability in VUR grading.
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- 2023
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21. Cerebral Semaphorin3D is a novel risk factor for age-associated cognitive impairment.
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Chen CY, Chao YM, Cho CC, Chen CS, Lin WY, Chen YH, Cassar M, Lu CS, Yang JL, Chan JYH, and Juo SH
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- Animals, Mice, Aging, Drosophila, Cognitive Dysfunction genetics, Dementia, MicroRNAs genetics
- Abstract
Background: We previously reported that miR-195 exerts neuroprotection by inhibiting Sema3A and cerebral miR-195 levels decreased with age, both of which urged us to explore the role of miR-195 and miR-195-regulated Sema3 family members in age-associated dementia., Methods: miR-195a KO mice were used to assess the effect of miR-195 on aging and cognitive functions. Sema3D was predicted as a miR-195 target by TargetScan and then verified by luciferase reporter assay, while effects of Sema3D and miR-195 on neural senescence were assessed by beta-galactosidase and dendritic spine density. Cerebral Sema3D was over-expressed by lentivirus and suppressed by si-RNA, and effects of over-expression of Sema3D and knockdown of miR-195 on cognitive functions were assessed by Morris Water Maze, Y-maze, and open field test. The effect of Sema3D on lifespan was assessed in Drosophila. Sema3D inhibitor was developed using homology modeling and virtual screening. One-way and two-way repeated measures ANOVA were applied to assess longitudinal data on mouse cognitive tests., Results: Cognitive impairment and reduced density of dendritic spine were observed in miR-195a knockout mice. Sema3D was identified to be a direct target of miR-195 and a possible contributor to age-associated neurodegeneration as Sema3D levels showed age-dependent increase in rodent brains. Injection of Sema3D-expressing lentivirus caused significant memory deficits while silencing hippocampal Sema3D improved cognition. Repeated injections of Sema3D-expressing lentivirus to elevate cerebral Sema3D for 10 weeks revealed a time-dependent decline of working memory. More importantly, analysis of the data on the Gene Expression Omnibus database showed that Sema3D levels were significantly higher in dementia patients than normal controls (p < 0.001). Over-expression of homolog Sema3D gene in the nervous system of Drosophila reduced locomotor activity and lifespan by 25%. Mechanistically, Sema3D might reduce stemness and number of neural stem cells and potentially disrupt neuronal autophagy. Rapamycin restored density of dendritic spines in the hippocampus from mice injected with Sema3D lentivirus. Our novel small molecule increased viability of Sema3D-treated neurons and might improve autophagy efficiency, which suggested Sema3D could be a potential drug target. Video Abstract CONCLUSION: Our results highlight the importance of Sema3D in age-associated dementia. Sema3D could be a novel drug target for dementia treatment., (© 2023. The Author(s).)
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- 2023
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22. Sex differences in blood pressure, free radicals and plasma cholesterol fractions in Ren-2 transgenic rats of various ages.
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Rauchová H, Hojná S, Kadlecová M, Vaněčková I, Chao YM, Chan J, and Zicha J
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- Animals, Female, Male, Rats, Blood Pressure, Cholesterol, Free Radicals, Glutathione, Kidney, Rats, Sprague-Dawley, Rats, Transgenic, Thiobarbituric Acid Reactive Substances, Sex Factors, Hypertension, Renin genetics
- Abstract
Sex-related cardiovascular differences were observed in humans as well as in experimental animals. Our previous study demonstrated a marked sexual dimorphism in blood pressure (BP) of 9-month-old heterozygous transgenic Ren 2 rats (TGR), in which mouse Ren-2 renin gene was inserted into the genome of normotensive Hannover Sprague-Dawley rats (HanSD). We found significantly elevated BP only in male TGR, whereas BP of TGR females was similar to that of HanSD females. The aim of our present study was to compare BP of 3- and 6-month-old heterozygous TGR with age- and sex-matched HanSD under the same conditions as we measured in 9-month-old rats. We also monitored the amount of oxidative stress marker, thiobarbituric acid-reactive substances (TBARS), and a main intracellular antioxidant, reduced glutathione in the heart, kidneys and liver. We also measured plasma triglycerides and cholesterol levels. We found an increased mean arterial pressure in both female and male 3-month-old TGR (172±17 vs. 187±4 mm Hg, respectively) compared to HanSD (115±5 vs. 133±3 mm Hg, respectively) but there was a marked sexual dimorphism of 6 month-old TGR where only males were hypertensive (145±5 mm Hg) while females became normotensive (123±7 mm Hg). We did not find any relationship between BP values and concentrations of TBARS or glutathione or plasma lipid levels. Our results demonstrated that 6-month-old TGR exhibited a marked sexual BP dimorphism, which was not dependent on the abnormalities in oxidative stress or cholesterol metabolism.
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- 2023
23. A Higher Abundance of Actinomyces spp. in the Gut Is Associated with Spontaneous Preterm Birth.
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Yu HR, Tsai CC, Chan JYH, Lee WC, Wu KLH, Tain YL, Hsu TY, Cheng HH, Huang HC, Huang CH, Pan WH, and Yeh YT
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Preterm birth is a major challenge in pregnancy worldwide. Prematurity is the leading cause of death in infants and may result in severe complications. Nearly half of preterm births are spontaneous, but do not have recognizable causes. This study investigated whether the maternal gut microbiome and associated functional pathways might play a key role in spontaneous preterm birth (sPTB). Two hundred eleven women carrying singleton pregnancies were enrolled in this mother-child cohort study. Fecal samples were freshly collected at 24-28 weeks of gestation before delivery, and the 16S ribosomal RNA gene was sequenced. Microbial diversity and composition, core microbiome, and associated functional pathways were then statistically analyzed. Demographic characteristics were collected using records from the Medical Birth Registry and questionnaires. The result showed that the gut microbiome of mothers with over-weight (BMI ≥ 24) before pregnancy have lower alpha diversity than those with normal BMI before pregnancy. A higher abundance of Actinomyces spp. was filtered out from the Linear discriminant analysis (LDA) effect size (LEfSe), Spearman correlation, and random forest model, and was inversely correlated with gestational age in sPTB. The multivariate regression model showed that the odds ratio of premature delivery was 3.274 [95% confidence interval (CI): 1.349; p = 0.010] in the group with over-weight before pregnancy with a cutoff Hit% > 0.022 for Actinomyces spp. The enrichment of Actinomyces spp. was negatively correlated with glycan biosynthesis and metabolism in sPTB by prediction from the Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) platform. Maternal gut microbiota showing a lower alpha diversity, increased abundance of Actinomyces spp., and dysregulated glycan metabolism may be associated with sPTB risk.
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- 2023
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24. Reprogramming Effects of Postbiotic Butyrate and Propionate on Maternal High-Fructose Diet-Induced Offspring Hypertension.
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Tain YL, Hou CY, Chang-Chien GP, Lin S, Tzeng HT, Lee WC, Wu KLH, Yu HR, Chan JYH, and Hsu CN
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- Pregnancy, Humans, Rats, Male, Female, Animals, Propionates, Rats, Sprague-Dawley, Butyrates, Fructose adverse effects, Diet, Diet, High-Fat, Prenatal Exposure Delayed Effects prevention & control, Hypertension chemically induced, Hypertension prevention & control
- Abstract
Maternal nutrition has a key role in the developmental programming of adult disease. Excessive maternal fructose intake contributes to offspring hypertension. Newly discovered evidence supports the idea that early-life gut microbiota are connected to hypertension later in life. Short-chain fatty acids (SCFAs), butyrate, and propionate are microbiota-derived metabolites, also known as postbiotics. The present study aimed to determine whether maternal butyrate or propionate supplementation can protect offspring from hypertension using a maternal high-fructose (HF) diet rat model. Female Sprague Dawley rats were allocated during pregnancy and lactation to (1) regular chow (ND); (2) 60% high-fructose diet (HF); (3) HF diet plus butyrate (HFB, 400 mg/kg/day); and (4) HF diet plus propionate (HFP, 200 mmol/L). Male offspring were sacrificed at 12 weeks of age. The maternal HF diet impaired the offspring's BP, which was prevented by perinatal butyrate or propionate supplementation. Both butyrate and propionate treatments similarly increased plasma concentrations of propionic acid, isobutyric acid, and valeric acid in adult offspring. Butyrate supplementation had a more profound impact on trimethylamine N-oxide metabolism and nitric oxide parameters. Whilst propionate treatment mainly influenced gut microbiota composition, it directly altered the abundance of genera Anaerovorax, Lactobacillus , Macellibacteroides , and Rothia . Our results shed new light on targeting gut microbiota through the use of postbiotics to prevent maternal HF intake-primed hypertension, a finding worthy of clinical translation.
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- 2023
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25. Impaired insulin signaling at the bladder mucosa facilitates metabolic syndrome-associated bladder overactivity in rats with maternal and post-weaning fructose exposure.
- Author
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Lee WC, Wu KLH, Tain YL, Leu S, Cheng YT, and Chan JYH
- Subjects
- Rats, Male, Animals, Urinary Bladder, Insulin adverse effects, Fructose adverse effects, Fructose metabolism, Weaning, Rats, Sprague-Dawley, Mucous Membrane metabolism, Adenosine Triphosphate adverse effects, Adenosine Triphosphate metabolism, Metabolic Syndrome, Urinary Bladder, Overactive
- Abstract
Background/purpose: Metabolic syndrome (MetS) and overactive bladder might share common pathophysiologies. Environmental fructose exposure during pre- and postnatal periods of rats may program MetS-associated bladder overactivity. We explored the dysregulated insulin signalling at bladder mucosa, as a common mechanism, in facilitating bladder overactivity in rats with MetS induced by maternal and post-weaning fructose diet., Methods: Male offspring of Sprague-Dawley rats were subject into 4 groups by maternal and post-weaning diets (i.e., Control/Control, Fructose/Control, Control/Fructose and Fructose/Fructose by diets). Micturition behavior was evaluated. Acidic ATP solution was used to elicit cystometric reflex along with insulin counteraction. Concentration-response curves to insulin were plotted. The canonical signalling pathway of insulin was evaluated in the bladder mucosal using Western blotting. Levels of detrusor cGMP and urinary NO
2 plus NO3 were measured., Results: Male offspring with any fructose exposure presents traits of MetS and bladder overactivity. We observed all fructose exposure groups have the poor urodynamic response to insulin during ATP solution stimulation and poor insulin-activated detrusor relaxation in organ bath study. Compared to controls, the Control/Fructose and Fructose/Fructose groups showed the increased phosphorylation levels of IRS1 (Ser307 ) and IRS2 (Ser731 ); thus, suppressed the downstream effectors and urinary NOx/detrusor cGMP levels. The Fructose/Control group showed the compensatory increase of phospho-AKT (Ser473 ) and phospho-eNOS/eNOS levels, but decreased in eNOS, phospho-eNOS, urinary NOx, and detrusor cGMP levels., Conclusion: Our results show dysregulated insulin signalling at bladder mucosa should be a common mechanism of MetS-associated bladder overactivity programmed by pre-and postnatal fructose diet., (Copyright © 2022. Published by Elsevier B.V.)- Published
- 2023
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26. Nephron-sparing surgery for renal cell carcinoma in children and young adults: A systematic review.
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Khondker A, Kwong JCC, Chua ME, Kim JK, Chan JYH, Zappitelli M, Brzezinski J, Cost NG, Rickard M, and Lorenzo AJ
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- Humans, Child, Young Adult, Nephrectomy adverse effects, Kidney pathology, Nephrons surgery, Treatment Outcome, Retrospective Studies, Carcinoma, Renal Cell pathology, Kidney Neoplasms pathology
- Abstract
Objective: To determine the patient characteristics and role of nephron-sparing surgery (NSS) in the treatment of children and young adults with renal cell carcinoma (RCC)., Methods: A systematic search of Embase, MEDLINE, and Scopus databases was conducted in December 2021 according to Cochrane collaboration recommendations. All included manuscripts were assessed for patient characteristics and all reported outcomes for patients undergoing partial nephrectomy (PN), and radical nephrectomy (RN) outcomes were abstracted as a comparison group. Primary outcomes included surgical outcomes, overall survival, kidney outcomes. Outcomes were pooled with weighted mean and ranges. Meta-analysis was not performed given study quality. This systematic review was prospectively registered on PROSPERO (CRD42022300261)., Results: We found a total of 16 studies describing 119 and 559 unique patients undergoing PN and RN, respectively, with a mean age of 12.2 years and mean follow-up of 59.1 months. The mean tumor size for patients undergoing PN was 3.5 cm. Of the 113 patients undergoing PN with available data, 109 were alive at follow-up (98%). No studies reported long-term kidney outcomes, and four studies reported surgical outcomes. All studies had at least moderate risk of bias., Conclusions: The use of NSS in children and young adults with RCC is feasible in selected patients. However, small sample sizes, confounding, and low study quality limit clinical recommendation on NSS in this population. There are significant opportunities for future research on the use of NSS in RCC, especially with systematic reporting of oncological, kidney, and surgical outcomes., Competing Interests: Conflicts of Interest All authors of this manuscript have directly participated in planning, execution, and/or analysis of this study. The authors have no conflicts of interest to disclose., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2023
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27. Impact of COVID-19 on the mortality of dialysis patients and kidney transplant recipients during the Omicron fifth wave in Hong Kong.
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Chow KM, Chan JYH, Wong SSH, Yuen SK, Wong PN, Cheng YL, and Szeto CC
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- Humans, Renal Dialysis, Hong Kong, Kidney Transplantation, COVID-19, Kidney Failure, Chronic
- Abstract
Competing Interests: All authors disclosed no conflicts of interest.
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- 2023
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28. The effect of primary urinary diversion on kidney function in posterior urethral valve: A matched comparison.
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Khondker A, Kim JK, Chua ME, Kwong JCC, Chan JYH, Yadav P, Richter J, Santos JD, Brownrigg N, Lorenzo AJ, and Rickard M
- Subjects
- Male, Humans, Urethra surgery, Creatinine, Kidney surgery, Retrospective Studies, Urethral Obstruction, Urinary Diversion adverse effects, Renal Insufficiency, Chronic complications, Kidney Failure, Chronic surgery
- Abstract
Objective: To determine long-term kidney outcomes in boys with posterior urethral valve (PUV) undergoing either primary valve ablation or urinary diversion with matched baseline kidney function., Methods: After retrospective review of patients managed for PUV at our institution, propensity score matched analysis was conducted using nadir serum creatinine with logistic regression analysis. Nearest neighbor matching was used to allocate boys to primary urinary diversion and primary ablation groups. Primary outcomes included kidney function by creatinine or estimated glomerular filtration rate, chronic kidney disease, and end-stage renal disease. Comparative statistics by odds ratio (OR) and hazard ratios on survival analysis were calculated., Results: A total of 21 boys undergoing primary diversion were matched with 42 boys undergoing ablation using nadir serum creatinine and follow-up time with a median follow-up of 4.8 years. After matching, there was no significant difference in last follow-up kidney function by creatinine (P = .99) or estimated glomerular filtration rate (P = .98). Primary diversion was not associated with increased likelihood of developing chronic kidney disease stage 3 (OR 1.33; P = .31) or end-stage renal disease (OR 1.88; P = .35 and hazard ratios 1.85; P = .30) compared to primary ablation., Conclusions: Our propensity matched study suggests that long-term kidney function and kidney outcomes are similar between primary ablation and primary diversion after adjusting for baseline kidney function in boys with PUV., Competing Interests: Conflicts of Interest The authors have no conflicts of interest to disclose., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2023
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29. Multi-institutional Validation of Improved Vesicoureteral Reflux Assessment With Simple and Machine Learning Approaches.
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Khondker A, Kwong JCC, Yadav P, Chan JYH, Singh A, Skreta M, Erdman L, Keefe DT, Fischer K, Tasian G, Hannick JH, Papanikolaou F, Cooper BJ, Cooper CS, Rickard M, and Lorenzo AJ
- Subjects
- Child, Humans, Reproducibility of Results, Cystography methods, Machine Learning, Retrospective Studies, Vesico-Ureteral Reflux diagnostic imaging, Ureter
- Abstract
Purpose: Vesicoureteral reflux grading from voiding cystourethrograms is highly subjective with low reliability. We aimed to demonstrate improved reliability for vesicoureteral reflux grading with simple and machine learning approaches using ureteral tortuosity and dilatation on voiding cystourethrograms., Materials and Methods: Voiding cystourethrograms were collected from our institution for training and 5 external data sets for validation. Each voiding cystourethrogram was graded by 5-7 raters to determine a consensus vesicoureteral reflux grade label and inter- and intra-rater reliability was assessed. Each voiding cystourethrogram was assessed for 4 features: ureteral tortuosity, proximal, distal, and maximum ureteral dilatation. The labels were then assigned to the combination of the 4 features. A machine learning-based model, qVUR, was trained to predict vesicoureteral reflux grade from these features and model performance was assessed by AUROC (area under the receiver-operator-characteristic)., Results: A total of 1,492 kidneys and ureters were collected from voiding cystourethrograms resulting in a total of 8,230 independent gradings. The internal inter-rater reliability for vesicoureteral reflux grading was 0.44 with a median percent agreement of 0.71 and low intra-rater reliability. Higher values for each feature were associated with higher vesicoureteral reflux grade. qVUR performed with an accuracy of 0.62 (AUROC=0.84) with stable performance across all external data sets. The model improved vesicoureteral reflux grade reliability by 3.6-fold compared to traditional grading ( P < . 001)., Conclusions: In a large pediatric population from multiple institutions, we show that machine learning-based assessment for vesicoureteral reflux improves reliability compared to current grading methods. qVUR is generalizable and robust with similar accuracy to clinicians but the added prognostic value of quantitative measures warrants further study.
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- 2022
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30. Milrinone effects on cardiac mitochondria, hemodynamics, and death in catecholamine-infused rats.
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Lin IC, Wu CW, Lin YJ, Lo MH, Hsieh KS, Chan JYH, and Wu KLH
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- Animals, Male, Rats, Milrinone pharmacology, Mitochondria, Heart, Catecholamines, Hemodynamics, Norepinephrine, Cardiotonic Agents pharmacology, Heart Failure drug therapy, Hypertension
- Abstract
Background: Catecholamine-storm is considered the major cause of enterovirus 71-associated cardiopulmonary death. To elucidate the effect of milrinone on cardiac mitochondria and death, a rat model of catecholamine-induced heart failure was investigated., Methods: Young male Spray-Dawley rats received a continuous intravenous infusion of norepinephrine then followed by co-treatment with and without milrinone or esmolol. Vital signs were monitored and echocardiography was performed at indicated time points. At the end of experiments, hearts were extracted to study mitochondrial function, biogenesis, and DNA copy numbers., Results: Hypernorepinephrinemia induced persistent tachycardia, hypertension, and high mortality and significantly impaired the activities of the electron transport chain and suppressed mitochondrial DNA copy number, mitochondrial transcription factor A and peroxisome proliferator-activated receptor-gamma coactivator 1-α. Norepinephrine-induced hypertension could be significantly suppressed by milrinone and esmolol. Milrinone improved but esmolol deteriorated the survival rate. The left ventricle was significantly enlarged shortly after norepinephrine infusion but later gradually reduced in size by milrinone. The impairment and suppression of mitochondrial function could be significantly reversed by milrinone but not by esmolol., Conclusions: Milrinone may protect the heart via maintaining mitochondrial function from hypernorepinephrinemia. This study warrants the importance of milrinone and the preservation of mitochondrial function in the treatment of catecholamine-induced death., Impact: Milrinone may protect the heart from hypernorepinephrinemia-induced death via maintaining myocardial mitochondrial activity, function, and copy number. Maintenance of cardiac mitochondrial function may be a potential therapeutic strategy in such catecholamine-induced heart failure., (© 2022. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)
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- 2022
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31. Vinpocetine Ameliorates Metabolic-Syndrome-Associated Bladder Overactivity in Fructose-Fed Rats by Restoring Succinate-Modulated cAMP Levels and Exerting Anti-Inflammatory Effects in the Bladder Detrusor Muscle.
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Lee WC, Yu HR, Tain YL, Wu KLH, Chuang YC, and Chan JYH
- Abstract
Succinate and its receptor, the G protein-coupled receptor 91 (GPR91), have pathological implications in metabolic syndrome (MetS) and its associated bladder dysfunction, particularly in decreasing bladder cAMP levels and promoting proinflammation. Using fructose-fed rats (FFRs), a rat model of MetS, we investigate the effects of vinpocetine (a phosphodiesterase-1 inhibitor) and celecoxib (a selective cyclooxygenase-2 inhibitor) on MetS-associated bladder overactivity. Phenotypes of the overactive bladder, including increased micturition frequency and a shortened intercontractile interval in cystometry, were observed in FFRs, together with elevated succinate levels in the liver and serum and the downregulation of GPR91 in the liver and urinary bladder. Treatments with vinpocetine and celecoxib improved tissue fibrosis and ameliorated the overexpression of the inflammatory cytokines, such as IL-1β, in the liver and bladder. In bladder organ bath studies, vinpocetine, but not celecoxib, treatment restored the contraction and relaxation responses of the detrusor muscle strip in response to KCl, carbachol, and forskolin stimulation. At a molecular level, vinpocetine and celecoxib treatments modulated the downstream messengers of GPR91 (i.e., ERK1/2 and JNK), suppressed NF-κB and IL-1β expressions in the bladder, and prevented the fibrogenesis observed in FFRs. The exogenous application of succinate to a bladder organ bath significantly reduced the forskolin-induced cAMP production by the detrusor muscle, which was notably restored in the presence of vinpocetine. Together, these results suggest that vinpocetine may alleviate the MetS-associated bladder overactivity by restoring the succinate-modulated detrusor cAMP production and exerting the anti-inflammatory effects in the bladder detrusor muscle.
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- 2022
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32. Protection by -Biotics against Hypertension Programmed by Maternal High Fructose Diet: Rectification of Dysregulated Expression of Short-Chain Fatty Acid Receptors in the Hypothalamic Paraventricular Nucleus of Adult Offspring.
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Chao YM, Tain YL, Lee WC, Wu KLH, Yu HR, and Chan JYH
- Subjects
- Animals, Rats, Female, Humans, Fructose adverse effects, Fructose metabolism, Antioxidants metabolism, Rats, Sprague-Dawley, Fatty Acids, Volatile metabolism, Diet, Anti-Inflammatory Agents metabolism, RNA, Messenger metabolism, Butyrates metabolism, Paraventricular Hypothalamic Nucleus metabolism, Hypertension prevention & control, Hypertension genetics
- Abstract
The role of short-chain fatty acids (SCFAs) in the brain on the developmental programming of hypertension is poorly understood. The present study explored dysregulated tissue levels of SCFAs and expression of SCFA-sensing receptors in the hypothalamic paraventricular nucleus (PVN), a key forebrain region engaged in neural regulation of blood pressure of offspring to maternal high fructose diet (HFD) exposure. We further investigated the engagement of SCFA-sensing receptors in PVN in the beneficial effects of -biotics (prebiotic, probiotic, synbiotic, and postbiotic) on programmed hypertension. Maternal HFD during gestation and lactation significantly reduced circulating butyrate, along with decreased tissue level of butyrate and increased expression of SCFA-sensing receptors, GPR41 and olfr78, and tissue oxidative stress and neuroinflammation in PVN of HFD offspring that were rectified by oral supplement with -biotics. Gene silencing of GPR41 or olfr78 mRNA in PVN also protected adult HFD offspring from programmed hypertension and alleviated the induced oxidative stress and inflammation in PVN. In addition, oral supplement with postbiotic butyrate restored tissue butyrate levels, rectified expressions of GPR41 and olfr78 in PVN, and protected against programmed hypertension in adult HFD offspring. These data suggest that alterations in tissue butyrate level, expression of GPR41 and olfr78, and activation of SCFA-sensing receptor-dependent tissue oxidative stress and neuroinflammation in PVN could be novel mechanisms that underlie hypertension programmed by maternal HFD exposure in adult offspring. Furthermore, oral -biotics supplementation may exert beneficial effects on hypertension of developmental origin by targeting dysfunctional SCFA-sensing receptors in PVN to exert antioxidant and anti-inflammatory actions in the brain.
- Published
- 2022
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33. Disparate Roles of Oxidative Stress in Rostral Ventrolateral Medulla in Age-Dependent Susceptibility to Hypertension Induced by Systemic l-NAME Treatment in Rats.
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Chao YM, Rauchová H, and Chan JYH
- Abstract
This study aims to investigate whether tissue oxidative stress in the rostral ventrolateral medulla (RVLM), where sympathetic premotor neurons reside, plays an active role in age-dependent susceptibility to hypertension in response to nitric oxide (NO) deficiency induced by systemic l-NAME treatment, and to decipher the underlying molecular mechanisms. Systolic blood pressure (SBP) and heart rate (HR) in conscious rats were recorded, along with measurements of plasma and RVLM level of NO and reactive oxygen species (ROS), and expression of mRNA and protein involved in ROS production and clearance, in both young and adult rats subjected to intraperitoneal (i.p.) infusion of l-NAME. Pharmacological treatments were administered by oral gavage or intracisternal infusion. Gene silencing of target mRNA was made by bilateral microinjection into RVLM of lentivirus that encodes a short hairpin RNA (shRNA) to knock down gene expression of NADPH oxidase activator 1 ( Noxa1 ). We found that i.p. infusion of l-NAME resulted in increases in SBP, sympathetic neurogenic vasomotor activity, and plasma norepinephrine levels in an age-dependent manner. Systemic l-NAME also evoked oxidative stress in RVLM of adult, but not young rats, accompanied by augmented enzyme activity of NADPH oxidase and reduced mitochondrial electron transport enzyme activities. Treatment with L-arginine via oral gavage or infusion into the cistern magna (i.c.), but not i.c. tempol or mitoQ
10 , significantly offset the l-NAME-induced hypertension in young rats. On the other hand, all treatments appreciably reduced l-NAME-induced hypertension in adult rats. The mRNA microarray analysis revealed that four genes involved in ROS production and clearance were differentially expressed in RVLM in an age-related manner. Of them, Noxa1 , and GPx2 were upregulated and Duox2 and Ucp3 were downregulated. Systemic l-NAME treatment caused greater upregulation of Noxa1 , but not Ucp3 , mRNA expression in RVLM of adult rats. Gene silencing of Noxa1 in RVLM effectively alleviated oxidative stress and protected adult rats against l-NAME-induced hypertension. These data together suggest that hypertension induced by systemic l-NAME treatment in young rats is mediated primarily by NO deficiency that occurs both in vascular smooth muscle cells and RVLM. On the other hand, enhanced augmentation of oxidative stress in RVLM may contribute to the heightened susceptibility of adult rats to hypertension induced by systemic l-NAME treatment.- Published
- 2022
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34. Maternal Acetate Supplementation Reverses Blood Pressure Increase in Male Offspring Induced by Exposure to Minocycline during Pregnancy and Lactation.
- Author
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Hsu CN, Yu HR, Chan JYH, Lee WC, Wu KLH, Hou CY, Chang-Chien GP, Lin S, and Tain YL
- Subjects
- Acetates pharmacology, Animals, Blood Pressure, Dietary Supplements, Female, Humans, Lactation, Male, Maternal Exposure adverse effects, Minocycline pharmacology, Pregnancy, Rats, Rats, Sprague-Dawley, Hypertension chemically induced, Hypertension drug therapy, Hypertension metabolism, Prenatal Exposure Delayed Effects prevention & control
- Abstract
Emerging evidence supports that hypertension can be programmed or reprogrammed by maternal nutrition. Maternal exposures during pregnancy, such as maternal nutrition or antibiotic use, could alter the offspring's gut microbiota. Short-chain fatty acids (SCFAs) are the major gut microbiota-derived metabolites. Acetate, the most dominant SCFA, has shown its antihypertensive effect. Limited information exists regarding whether maternal acetate supplementation can prevent maternal minocycline-induced hypertension in adult offspring. We exposed pregnant Sprague Dawley rats to normal diet (ND), minocycline (MI, 50 mg/kg/day), magnesium acetate (AC, 200 mmol/L in drinking water), and MI + AC from gestation to lactation period. At 12 weeks of age, four groups ( n = 8/group) of male progeny were sacrificed. Maternal acetate supplementation protected adult offspring against minocycline-induced hypertension. Minocycline administration reduced plasma acetic acid level, which maternal acetate supplementation prevented. Additionally, acetate supplementation increased the protein level of SCFA receptor G protein-coupled receptor 41 in the offspring kidneys. Further, minocycline administration and acetate supplementation significantly altered gut microbiota composition. Maternal acetate supplementation protected minocycline-induced hypertension accompanying by the increases in genera Roseburia , Bifidobacterium , and Coprococcus . In sum, our results cast new light on targeting gut microbial metabolites as early interventions to prevent the development of hypertension, which could help alleviate the global burden of hypertension.
- Published
- 2022
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35. Should Canadian urology adopt structured reference letters for residency matching?
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Nguyen DD, Chan JYH, Andonian S, Fahmy N, Letendre J, Perrotte P, Lee JY, and Bhojani N
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- 2022
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36. The Impact of Gut Microbiome on Maternal Fructose Intake-Induced Developmental Programming of Adult Disease.
- Author
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Hsu CN, Yu HR, Chan JYH, Wu KLH, Lee WC, and Tain YL
- Subjects
- Animals, Diet, Female, Fructose adverse effects, Humans, Maternal Nutritional Physiological Phenomena, Rats, Rats, Sprague-Dawley, Gastrointestinal Microbiome
- Abstract
Excessive or insufficient maternal nutrition can influence fetal development and the susceptibility of offspring to adult disease. As eating a fructose-rich diet is becoming more common, the effects of maternal fructose intake on offspring health is of increasing relevance. The gut is required to process fructose, and a high-fructose diet can alter the gut microbiome, resulting in gut dysbiosis and metabolic disorders. Current evidence from animal models has revealed that maternal fructose consumption causes various components of metabolic syndrome in adult offspring, while little is known about how gut microbiome is implicated in fructose-induced developmental programming and the consequential risks for developing chronic disease in offspring. This review will first summarize the current evidence supporting the link between fructose and developmental programming of adult diseases. This will be followed by presenting how gut microbiota links to common mechanisms underlying fructose-induced developmental programming. We also provide an overview of the reprogramming effects of gut microbiota-targeted therapy on fructose-induced developmental programming and how this approach may prevent adult-onset disease. Using gut microbiota-targeted therapy to prevent maternal fructose diet-induced developmental programming, we have the potential to mitigate the global burden of fructose-related disorders.
- Published
- 2022
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37. Road to the 39th IUPS Congress Amid COVID-19 Pandemic: Every Cloud Has a Silver Lining.
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Pohl U and Chan JYH
- Subjects
- Humans, SARS-CoV-2, COVID-19, Pandemics
- Published
- 2021
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38. Maternal Fructose Intake Exacerbates Cardiac Remodeling in Offspring with Ventricular Pressure Overload.
- Author
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Leu S, Wu KLH, Lee WC, Tain YL, and Chan JYH
- Subjects
- Animals, Aorta, Cardiomegaly genetics, Constriction, Female, Fructose administration & dosage, Gene Expression, Heart drug effects, Heart embryology, Lactation, Male, Myocardium metabolism, Oxidative Stress, Pregnancy, Rats, Cardiomegaly etiology, Fructose adverse effects, Heart growth & development, Myocardium pathology, Prenatal Exposure Delayed Effects, Ventricular Pressure physiology
- Abstract
Recent studies demonstrated that metabolic syndrome and cardiovascular diseases could be elicited by developmental programming, which is regulated by prenatal nutritional and environmental stress. In this study, we utilized a rat model to examine the effect of excessive maternal fructose intake during pregnancy and lactation on cardiac development and progression of pressure overload-induced cardiac hypertrophy in offspring. Transverse aortic constriction (TAC) was performed on 3-month-old male offspring to induce ventricular pressure overload. Four weeks post-TAC, echocardiographic assessment as well as histopathological and biochemical examinations were performed on the myocardium of the offspring. Echocardiographic and gross examinations showed that heart weight, interventricular septal thickness in diastole (IVD; d), and left ventricular posterior wall thickness in diastole (LVPW; d) were elevated in offspring with TAC and further increased by maternal fructose exposure (MFE). However, the left ventricular ejection function was not significantly affected. Myocardial histopathological examination revealed that the indices of fibrosis and oxidative stress were higher in offspring with MFE and TAC than those in animals receiving either treatment. Molecular examinations on the myocardium demonstrated an MFE-induced upregulation of p38-MAPK signaling. Next generation sequence (NGS) analysis indicated a modulation of the expression levels of several cardiac hypertrophy-associated genes, including GPR22, Myh7, Nppa, P2RX4, and Npy by MFE. Subsequent RT-PCR indicated that MFE regulated the expression levels of genes responsive to cardiac hypertrophy (i.e., Myh-7, ANP) and oxidative stress (i.e., GR, GPx, and NQO-1). In conclusion, MFE during pregnancy and lactation modulated myocardial gene expression, increased oxidative stress, and exacerbated ventricular pressure overload-induced cardiac remodeling in rat offspring.
- Published
- 2021
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39. Maternal resveratrol therapy protected adult rat offspring against hypertension programmed by combined exposures to asymmetric dimethylarginine and trimethylamine-N-oxide.
- Author
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Hsu CN, Hou CY, Chang-Chien GP, Lin S, Chan JYH, Lee CT, and Tain YL
- Subjects
- Animals, Antioxidants administration & dosage, Antioxidants pharmacology, Arginine toxicity, Female, Gastrointestinal Microbiome drug effects, Pregnancy, Prenatal Exposure Delayed Effects, Prenatal Nutritional Physiological Phenomena, Rats, Renin-Angiotensin System drug effects, Resveratrol administration & dosage, Arginine analogs & derivatives, Hypertension chemically induced, Hypertension prevention & control, Methylamines toxicity, Resveratrol pharmacology
- Abstract
Resveratrol, a phytochemical, has shown antioxidant properties and potential benefits in hypertension. Asymmetric dimethylarginine (ADMA)-related nitric oxide deficiency and gut microbiota-derived metabolite trimethylamine-N-oxide (TMAO) have been linked to hypertension. We aimed to test whether maternal resveratrol therapy would protect adult offspring against hypertension programmed by prenatal exposure to ADMA and TMAO. Pregnant Sprague-Dawley rats received ADMA 10 mg/kg/day (A), TMAO 0.65 mg/hr (T), ADMA+TMAO (AT), or vesicle (CV). One group of ADMA+TMAO-exposed rats received 50 mg/L of resveratrol in drinking water during pregnancy and lactation periods (ATR). Male offspring (n = 8/group) were assigned to five groups: CV, A, T, AT, and ATR. Rats were killed at 12 weeks of age. ADMA exposure caused the elevation of blood pressure in 12-week-old male offspring, which was exacerbated by TMAO exposure. Treatment with resveratrol rescued hypertension programmed by combined ADMA and TMAO exposure. This was accompanied by alterations in the compositions of gut microbiota and increased fecal butyrate levels. Both the abundance of the butyrate-producing genera Lachnospiraceae and Ruminococcaceae were augmented by resveratrol. Meanwhile, resveratrol therapy significantly increased the abundance of the Cyanobiaceae and Erysipelotrichaceae families. Moreover, the protective effects of resveratrol were related to the mediation of the renin-angiotensin system . Our data provide new insights into the protective mechanisms of resveratrol against hypertension programmed by ADMA and TMAO, including regulation of gut microbiota and their metabolites, the renin-angiotensin system, and nitric oxide pathway. Resveratrol might be a potential reprogramming strategy to protect against the hypertension of developmental origins., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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40. Prenatal Exposure to Di-Ethyl Phthalate (DEP) Is Related to Increasing Neonatal IgE Levels and the Altering of the Immune Polarization of Helper-T Cells.
- Author
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Tsai CK, Cheng HH, Hsu TY, Wang JY, Hung CH, Tsai CC, Lai YJ, Lin YJ, Huang HC, Chan JYH, Tain YL, Chen CC, Tsai TA, and Yu HR
- Subjects
- Adult, Child, Environmental Exposure, Female, Humans, Immunoglobulin E, Infant, Newborn, Maternal Exposure adverse effects, Pregnancy, T-Lymphocytes, Phthalic Acids toxicity, Prenatal Exposure Delayed Effects
- Abstract
Introduction: Phthalates are substances that are added to plastic products to increase their plasticity. These substances are released easily into the environment and can act as endocrine disruptors. Epidemiological studies in children have showed inconsistent findings regarding the relationship between prenatal or postnatal exposure to phthalates and the risk of allergic disease. Our hypothesis is that prenatal exposure to phthalates may contribute to the development of allergies in children. Material and methods: The objective of this study was to determine the associations between urinary phthalate metabolite concentrations in pregnant women, maternal atopic diathesis, maternal lifestyle, and cord blood IgE. Pregnant mothers and paired newborns (n = 101) were enrolled from an antenatal clinic. The epidemiologic data and the clinical information were collected using standard questionnaires and medical records. The maternal blood and urine samples were collected at 24-28 weeks gestation, and cord blood IgE, IL-12p70, IL-4, and IL-10 levels were determined from the newborns at birth. The link between phthalates and maternal IgE was also assessed. To investigate the effects of phthalates on neonatal immunity, cord blood mononuclear cells (MNCs) were used for cytokine induction in another in vitro experiment. Results: We found that maternal urine monoethyl phthalate (MEP) (a metabolite of di-ethyl phthalate (DEP)) concentrations are positively correlated with the cord blood IgE of the corresponding newborns. The cord blood IL-12p70 levels of mothers with higher maternal urine MEP groups (high DEP exposure) were lower than mothers with low DEP exposure. In vitro experiments demonstrated that DEP could enhance IL-4 production of cord blood MNCs rather than adult MNCs. Conclusion: Prenatal DEP exposure is related to neonatal IgE level and alternation of cytokines relevant to Th1/Th2 polarization. This suggests the existence of a link between prenatal exposure to specific plasticizers and the future development of allergies.
- Published
- 2021
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41. Tadalafil ameliorates bladder overactivity by restoring insulin-activated detrusor relaxation via the bladder mucosal IRS/PI3K/AKT/eNOS pathway in fructose-fed rats.
- Author
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Lee WC, Leu S, Wu KLH, Tain YL, Chuang YC, and Chan JYH
- Subjects
- Animals, Diet, Carbohydrate Loading, Dietary Carbohydrates pharmacology, Female, Insulin metabolism, Insulin pharmacology, Insulin Receptor Substrate Proteins metabolism, Mucous Membrane drug effects, Mucous Membrane metabolism, Muscle, Smooth drug effects, Muscle, Smooth metabolism, Muscle, Smooth pathology, Nitric Oxide Synthase Type III metabolism, Phosphatidylinositol 3-Kinases metabolism, Proto-Oncogene Proteins c-akt metabolism, Rats, Rats, Wistar, Signal Transduction drug effects, Urinary Bladder metabolism, Urinary Bladder physiopathology, Urinary Bladder, Overactive drug therapy, Urinary Bladder, Overactive metabolism, Urinary Bladder, Overactive pathology, Urination physiology, Fructose pharmacology, Tadalafil pharmacology, Urinary Bladder drug effects, Urinary Bladder, Overactive physiopathology, Urination drug effects
- Abstract
The pathophysiologies of metabolic syndrome (MS) and overactive bladder (OAB) might overlap. Using fructose-fed rats (FFRs) as a rodent model of MS we investigated the effects of tadalafil (a phosphodiesterase type 5 inhibitor) on the dysregulated insulin signalling in the bladder mucosa and bladder overactivity. Micturition behaviour was evaluated. Concentration-response curves on detrusor relaxation to insulin stimulation were examined. Expression and phosphorylation of proteins in the insulin signalling pathway were evaluated by Western blotting. Levels of detrusor cGMP and urinary nitrite and nitrate (NOx) were measured. We observed FFRs exhibited metabolic traits of MS, bladder overactivity, and impaired insulin-activated detrusor relaxation in organ bath study. A high-fructose diet also impeded insulin signalling, reflected by overexpression of IRS1/pIRS1
Ser307 and pIRS2Ser731 and downregulation of PI3K/pPI3KTyr508 , AKT/pAKTSer473 , and eNOS/peNOSSer1177 in the bladder mucosa, alongside decreased urinary NOx and detrusor cGMP levels. Tadalafil treatment restored the reduced level of mucosal peNOS, urinary NOx, and detrusor cGMP, improved the insulin-activated detrusor relaxation, and ameliorated bladder overactivity in FFRs. These results suggest tadalafil may ameliorate MS-associated bladder overactivity by restoring insulin-activated detrusor relaxation via molecular mechanisms that are associated with preservation of IR/IRS/PI3K/AKT/eNOS pathway in the bladder mucosa and cGMP production in the bladder detrusor.- Published
- 2021
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42. Altered Gut Microbiota and Its Metabolites in Hypertension of Developmental Origins: Exploring Differences between Fructose and Antibiotics Exposure.
- Author
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Hsu CN, Chan JYH, Wu KLH, Yu HR, Lee WC, Hou CY, and Tain YL
- Subjects
- Animals, Anti-Bacterial Agents administration & dosage, Fatty Acids, Volatile metabolism, Female, Gastrointestinal Microbiome drug effects, Gram-Negative Bacteria drug effects, Gram-Negative Bacteria isolation & purification, Gram-Negative Bacteria metabolism, Gram-Positive Bacteria drug effects, Gram-Positive Bacteria isolation & purification, Gram-Positive Bacteria metabolism, Hypertension etiology, Kidney drug effects, Kidney metabolism, Lactation, Male, Minocycline administration & dosage, Nitric Oxide metabolism, Pregnancy, Rats, Rats, Sprague-Dawley, Receptors, Cell Surface biosynthesis, Receptors, Cell Surface genetics, Renin-Angiotensin System physiology, Anti-Bacterial Agents toxicity, Fructose toxicity, Gastrointestinal Microbiome physiology, Hypertension microbiology, Minocycline toxicity, Prenatal Exposure Delayed Effects
- Abstract
Gut microbiota-derived metabolites, in particular short chain fatty acids (SCFAs) and their receptors, are linked to hypertension. Fructose and antibiotics are commonly used worldwide, and they have a negative impact on the gut microbiota. Our previous study revealed that maternal high-fructose (HF) diet-induced hypertension in adult offspring is relevant to altered gut microbiome and its metabolites. We, therefore, intended to examine whether minocycline administration during pregnancy and lactation may further affect blood pressure (BP) programmed by maternal HF intake via mediating gut microbiota and SCFAs. Pregnant Sprague-Dawley rats received a normal diet or diet containing 60% fructose throughout pregnancy and lactation periods. Additionally, pregnant dams received minocycline (50 mg/kg/day) via oral gavage or a vehicle during pregnancy and lactation periods. Four groups of male offspring were studied ( n = 8 per group): normal diet (ND), high-fructose diet (HF), normal diet + minocycline (NDM), and HF + minocycline (HFM). Male offspring were killed at 12 weeks of age. We observed that the HF diet and minocycline administration, both individually and together, causes the elevation of BP in adult male offspring, while there is no synergistic effect between them. Four groups displayed distinct enterotypes. Minocycline treatment leads to an increase in the F/B ratio, but decreased abundance of genera Lactobacillus , Ruminococcus , and Odoribacter . Additionally, minocycline treatment decreases plasma acetic acid and butyric acid levels. Hypertension programmed by maternal HF diet plus minocycline exposure is related to the increased expression of several SCFA receptors. Moreover, minocycline- and HF-induced hypertension, individually or together, is associated with the aberrant activation of the renin-angiotensin system (RAS). Conclusively, our results provide a new insight into the support of gut microbiota and its metabolite SCAFs in the developmental programming of hypertension and cast new light on the role of RAS in this process, which will help prevent hypertension programmed by maternal high-fructose and antibiotic exposure.
- Published
- 2021
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43. Is Stone-free Status After Surgical Intervention for Kidney Stones Associated With Better Health-related Quality of Life? - A Multicenter Study From the North American Stone Quality of Life Consortium.
- Author
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Streeper NM, Galida M, Boltz S, Li S, Nakada SY, Raffin EP, Brown DR, Pais VM, Chan JYH, Scotland KB, Chew BH, and Penniston KL
- Subjects
- Adult, Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Humans, Kidney Calculi diagnosis, Kidney Calculi psychology, Longitudinal Studies, Male, Middle Aged, North America, Postoperative Period, Prospective Studies, Retrospective Studies, Surveys and Questionnaires statistics & numerical data, Treatment Outcome, Young Adult, Kidney Calculi surgery, Quality of Life, Urologic Surgical Procedures statistics & numerical data
- Abstract
Objective: To compare the health-related quality of life (HRQOL) of patients with residual fragments after surgical intervention for kidney stones to patients that are stone-free using the disease-specific Wisconsin stone quality of life (WISQOL) questionnaire. Kidney stones contribute to impaired HRQOL, which is increasingly recognized as an important healthcare outcome measurement., Materials and Methods: With institutional review board approval, 313 adult patients who underwent surgical intervention for kidney stones at 4 sites completed a WISQOL questionnaire. We retrospectively collected surgical data including presence of residual fragments on post-operative imaging. We calculated standardized WISQOL total and domain scores (0-100), which included items related to social functioning (D1), emotional functioning (D2), stone-related impact (D3), and vitality (D4). Scores were compared between patients with residual fragments to those who were stone-free after surgical intervention., Results: Demographics did not differ between groups, overall mean age 54.6 ± 13.5 and 55.4% female. There was no significant difference in total WISQOL score for patients with residual fragments (n = 124) compared to patients that were stone-free (n = 189), 110.5 ± 27.8 vs 115.4 ± 23.6 respectively, (P = .12). Interestingly, patients with residual fragments who underwent secondary surgery were found to have significantly lower total WISQOL score (88.4 ± 30.1 vs 116.6 ± 25.0, P <.0001)., Conclusion: Stone-free status after surgical intervention is not associated with better HRQOL when compared with patients whose surgeries left residual fragments. Indeed, further surgical intervention on residual fragments to achieve stone-free status may actually result in worse HRQOL., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2021
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44. Disproportional cardiovascular depressive effects of isoflurane: Serendipitous findings from a comprehensive re-visit in mice.
- Author
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Poon YY, Tsai CY, Huang YH, Wu JCC, Chan SHH, and Chan JYH
- Subjects
- Animals, Baroreflex, Blood Pressure, Heart Rate, Male, Mice, Mice, Inbred C57BL, Isoflurane
- Abstract
Employment of anesthetics, including isoflurane, though mandatory in animal experiments, is often regarded as a major limitation because results obtained with anesthetics may be different from those obtained under a conscious state. This study re-visits two issues related to the use of isoflurane. First, does isoflurane exert depression equally on all aspects of cardiovascular functions and their regulations? Second, is the circulatory supply of oxygen to brain tissues sufficient under isoflurane anesthesia? We determined in male C57BL/6J mice the temporal effects of 1.5% (vol/vol) isoflurane on blood pressure (BP), heart rate (HR), cardiac performance, baroreflex-mediated sympathetic vasomotor tone, cardiac vagal baroreflex, functional connectivity within the baroreflex neural circuits, carotid or cerebral blood flow, cortical tissue oxygen level, respiratory rate and blood gas. Over 150 min after exposure to 1.5% isoflurane, BP and HR were sustained at 71% and 79% of their awake levels amid a trend of progressive increase. Cardiac performance was within physiological ranges. Baroreflex-mediated sympathetic vasomotor tone gradually reversed from an 85% reduction toward the conscious level, alongside a parallel decrease in inhibitory connectivity between nucleus tractus solitarii (NTS) and rostral ventrolateral medulla. A decline in excitatory connectivity between NTS and nucleus ambiguus accompanied the decrease in cardiac vagal baroreflex. There were progressive increases in carotid or cerebral blood flow and tissue oxygen tension in cerebral cortex, alongside gradual hypoventilation, mild respiratory acidosis and hypercapnia. We conclude that, by eliciting disproportional depressive actions on cardiovascular functions and their regulations, which sustain circulatory supply of oxygen to brain tissues, 1.5% isoflurane is sufficient to maintain optimal cardiovascular functions in mice.
- Published
- 2021
- Full Text
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45. IUPS Physiology Education Workshop series in India: organizational mechanics, outcomes, and lessons.
- Author
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Chandran DS, Muthukrishnan SP, Barman SM, Peltonen LM, Ghosh S, Sharma R, Bhattacharjee M, Rathore BB, Carroll RG, Sengupta J, Chan JYH, and Ghosh D
- Subjects
- Educational Status, Health Personnel, Humans, India, Curriculum, Problem-Based Learning
- Abstract
Active learning promotes the capacity of problem solving and decision making among learners. Teachers who apply instructional processes toward active participation of learners help their students develop higher order thinking skills. Due to the recent paradigm shift toward adopting competency-based curricula in the education of healthcare professionals in India, there is an emergent need for physiology instructors to be trained in active-learning methodologies and to acquire abilities to promote these curriculum changes. To address these issues, a series of International Union of Physiological Sciences (IUPS) workshops on physiology education techniques in four apex centers in India was organized in November 2018 and November 2019. The "hands-on" workshops presented the methodologies of case-based learning, problem-based learning, and flipped classroom; the participants were teachers of basic sciences and human and veterinary medicine. The workshop series facilitated capacity building and creation of a national network of physiology instructors interested in promoting active-learning techniques. The workshops were followed by a brainstorming meeting held to assess the outcomes. The aim of this report is to provide a model for implementing a coordinated series of workshops to support national curriculum change and to identify the organizational elements essential for conducting an effective Physiology Education workshop. The essential elements include a highly motivated core organizing team, constant dialogue between core organizing and local organizing committees, a sufficient time frame for planning and execution of the event, and opportunities to engage students at host institutions in workshop activities.
- Published
- 2020
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46. Covid-19 dermatoses: Acral vesicular pattern evolving into bullous pemphigoid.
- Author
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Goon PKC, Bello O, Adamczyk LA, Chan JYH, Sudhoff H, and Banfield CC
- Abstract
Bullous pemphigoid (BP) appears to be rising in incidence across the Western World, especially in the elderly. Some of the pathogenetic mechanisms involving antigen mimicry and antibody cross-reactivity have been elucidated for cases associated with neurological disease and certain drugs. There have been reports of cutaneous manifestations of Covid-19 (SARS-Cov2 infection) as the pandemic has raged across the world. We report here a case of prolonged Covid-19, symptomatic with dermatoses only, which was seen to evolve initially from a maculo-papular exanthema with acral vesicular dermatitis, into classical BP disease. This was confirmed histologically by positive skin autoantibody serology, direct IMF on peri-lesional skin and also salt-split IMF. Although possible that the development of BP could be a purely co-incidental finding during Covid-19, we suggest that it is more likely that prolonged SARS-Cov2 infection triggered an autoimmune response to the basement membrane antigens, BP 180 and 230. To our knowledge, this is the first case of BP developing during concurrent Covid-19 disease. It will be necessary to continue dermatological surveillance as the pandemic continues, to collate data on BP incidence and to test these patients for Covid-19 disease. As the pandemic continues, even potential and rare associations such as this will be clarified eventually. What's already known about this topic? Covid-19 disease has been associated with a spectrum of dermatosesCommon presentations in up to 20% of patients include exanthema, pseudo-chilblain like acral lesions 'Covid toes', livedo-/retiform purpuric/necrotic vascular lesions, acute urticarial lesions, and vesicular/varicella-like lesionsA multi-system inflammatory syndrome in children akin to Kawasaki syndrome has been described What does this study add? To our knowledge, this is the first description of classic Bullous Pemphigoid evolving from vesicular lesions caused by prolonged SARS-Cov2 induced skin inflammation., Competing Interests: No conflict of interests have been declared., (© 2020 The Authors. Skin Health and Disease published by John Wiley & Sons Ltd on behalf of British Association of Dermatologists.)
- Published
- 2020
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47. miR-195 reduces age-related blood-brain barrier leakage caused by thrombospondin-1-mediated selective autophagy.
- Author
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Chen CY, Chao YM, Lin HF, Chen CJ, Chen CS, Yang JL, Chan JYH, and Juo SH
- Subjects
- Animals, Autophagy physiology, Blood-Brain Barrier cytology, Male, Mice, Transfection, Blood-Brain Barrier metabolism, MicroRNAs metabolism, Thrombospondin 1 metabolism
- Abstract
Blood-brain barrier (BBB) disruption contributes to neurodegenerative diseases. Loss of tight junction (TJ) proteins in cerebral endothelial cells (ECs) is a leading cause of BBB breakdown. We recently reported that miR-195 provides vasoprotection, which urges us to explore the role of miR-195 in BBB integrity. Here, we found cerebral miR-195 levels decreased with age, and BBB leakage was significantly increased in miR-195 knockout mice. Furthermore, exosomes from miR-195-enriched astrocytes increased endothelial TJ proteins and improved BBB integrity. To decipher how miR-195 promoted BBB integrity, we first demonstrated that TJ proteins were metabolized via autophagic-lysosomal pathway and the autophagic adaptor p62 was necessary to promote TJ protein degradation in cerebral ECs. Next, proteomic analysis of exosomes revealed miR-195-suppressed thrombospondin-1 (TSP1) as a major contributor to BBB disruption. Moreover, TSP1 was demonstrated to activate selective autophagy of TJ proteins by increasing the formation of claudin-5-p62 and ZO1-p62 complexes in cerebral ECs while TSP1 impaired general autophagy. Delivering TSP1 antibody into the circulation showed dose-dependent reduction of BBB leakage by 20%-40% in 25-month-old mice. Intravenous or intracerebroventricular injection of miR-195 rescued TSP1-induced BBB leakage. Dementia patients with BBB damage had higher levels of serum TSP1 compared to those without BBB damage (p = 0.0015), while the normal subjects had the lowest TSP1 (p < 0.0001). Taken together, the study implies that TSP1-regulated selective autophagy facilitates the degradation of TJ proteins and weakens BBB integrity. An adequate level of miR-195 can suppress the autophagy-lysosome pathway via a reduction of TSP1, which may be important for maintaining BBB function., (© 2020 The Authors. Aging Cell published by Anatomical Society and John Wiley & Sons Ltd.)
- Published
- 2020
- Full Text
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48. Sympathetic activation of splenic T-lymphocytes in hypertension of adult offspring programmed by maternal high fructose exposure.
- Author
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Tsai PC, Chao YM, and Chan JYH
- Subjects
- Blood Pressure, CD8-Positive T-Lymphocytes, Fructose, Humans, Hypertension, Spleen
- Abstract
Whereas neuroimmune crosstalk between the sympathetic nervous system (SNS) and immune cells in the pathophysiology of hypertension is recognized, the exact effect of SNS on T-lymphocyte in hypertension remains controversial. This study assessed the hypothesis that excitation of the SNS activates splenic T-lymphocytes through redox signaling, leading to the production of pro-inflammatory cytokines and the development of hypertension. Status of T-lymphocyte activation, reactive oxygen species (ROS) production and pro-inflammatory cytokines expression in the spleen were examined in a rodent model of hypertension programmed by maternal high fructose diet (HFD) exposure. Maternal HFD exposure enhanced SNS activity and activated both CD4
+ and CD8+ T-lymphocytes in the spleen of young offspring, compared to age-matched offspring exposed to maternal normal diet (ND). Maternal HFD exposure also induced tissue oxidative stress and expression of pro-inflammatory cytokines in the spleen of HFD offspring. All those cellular and molecular events were ameliorated following splenic nerve denervation (SND) by thermoablation. In contrast, activation of splenic sympathetic nerve by nicotine treatment resulted in the enhancement of tissue ROS level and activation of CD4+ and CD8+ T-cells in the spleen of ND offspring; these molecular events were attenuated by treatment with a ROS scavenger, tempol. Finally, the increase in systolic blood pressure (SBP) programmed in adult offspring by maternal HFD exposure was diminished by SND, whereas activation of splenic sympathetic nerve increased basal SBP in young ND offspring. These findings suggest that excitation of the SNS may activate splenic T-lymphocytes, leading to hypertension programming in adult offspring induced by maternal HFD exposure. Moreover, tissue oxidative stress induced by the splenic sympathetic overactivation may serve as a mediator that couples the neuroimmune crosstalk to prime programmed hypertension in HFD offspring., Competing Interests: None- Published
- 2020
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49. Evaluation of a Single-Use Flexible Cystoscope: A Multi-Institutional International Study.
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Scotland K, Wong VKF, Chan JYH, Tawfiek E, Chiura A, Chew BH, and Bagley D
- Subjects
- Canada, Egypt, Equipment Design, Humans, Cystoscopes, Cystoscopy
- Abstract
Introduction: Acquisition costs and prohibitively expensive technical support for endoscope maintenance, repair, and reprocessing have deterred adoption of flexible cystoscopes by many urologists internationally. This study evaluated the performance of a novel single-use digital cystoscope that can directly connect to a laptop or computer monitor for visualization, obviating the need for a tower. Materials and Methods: The performance characteristics of flexible single-use cystoscopes (NeoScope) were prospectively evaluated vs a reusable flexible cystoscope (Olympus) in three clinical cases and two independent benchtop testing episodes in Canada. Cystoscope maneuverability, imaging, deflection, irrigation, and ease of use of instrumentation were investigated. Additional investigations were performed during clinical use in Zimbabwe (7 patients), Egypt (10 patients), and Dominica (5 patients). Results: Bench testing revealed smaller tip diameter (4.06 vs 6.09 mm) and shorter (35.4 vs 38 cm) single-use cystoscopes vs reusable cystoscopes. Deflection of the single-use scope was superior with an empty working channel (230 up/220 down) vs the reusable (195 up/95 down) but showed a more substantial decrease in deflection on placement of instruments including a grasper. Clinical use revealed satisfactory maneuverability, ease of use of instruments, deflection, and visualization. Conclusions: Benchtop testing performance of the single-use digital flexible cystoscopes was inferior compared with reusable digital cystoscopes. However, these single-use endoscopes offer adequate illumination, imaging, and maneuverability. Direct connection to any computer monitor allowed truly portable use, allowing for treatment of patients in a variety of clinical settings without the need for ancillary equipment.
- Published
- 2020
- Full Text
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50. Targeting on Gut Microbiota-Derived Metabolite Trimethylamine to Protect Adult Male Rat Offspring against Hypertension Programmed by Combined Maternal High-Fructose Intake and Dioxin Exposure.
- Author
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Hsu CN, Chan JYH, Yu HR, Lee WC, Wu KLH, Chang-Chien GP, Lin S, Hou CY, and Tain YL
- Subjects
- Animals, Dioxins adverse effects, Female, Fructose adverse effects, Male, Methylamines pharmacology, Pregnancy, Protective Agents pharmacology, Rats, Rats, Sprague-Dawley, Diet, Carbohydrate Loading adverse effects, Gastrointestinal Microbiome, Hypertension, Maternal Exposure adverse effects, Prenatal Exposure Delayed Effects
- Abstract
Gut microbiota-dependent metabolites, in particular trimethylamine (TMA), are linked to hypertension. Maternal 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure or consumption of food high in fructose (HFR) can induce hypertension in adult offspring. We examined whether 3,3-maternal dimethyl-1-butanol (DMB, an inhibitor of TMA formation) therapy can protect adult offspring against hypertension arising from combined HFR and TCDD exposure. Pregnant Sprague-Dawley rats received regular chow or chow supplemented with fructose (60% diet by weight) throughout pregnancy and lactation. Additionally, the pregnant dams received TCDD (200 ng/kg BW orally) or a corn oil vehicle on days 14 and 21 of gestation, and days 7 and 14 after birth. Some mother rats received 1% DMB in their drinking water throughout pregnancy and lactation. Six groups of male offspring were studied ( n = 8 for each group): regular chow (CV), high-fructose diet (HFR), regular diet+TCDD exposure (CT), HFR+TCDD exposure (HRT), high-fructose diet+DMB treatment (HRD), and HFR+TCDD+DMB treatment (HRTD). Our data showed that TCDD exacerbates HFR-induced elevation of blood pressure in male adult offspring, which was prevented by maternal DMB administration. We observed that different maternal insults induced distinct enterotypes in adult offspring. The beneficial effects of DMB are related to alterations of gut microbiota, the increase in nitric oxide (NO) bioavailability, the balance of the renin-angiotensin system, and antagonization of aryl hydrocarbon receptor (AHR) signaling. Our findings cast new light on the role of early intervention targeting of the gut microbiota-dependent metabolite TMA, which may allow us to prevent the development of hypertension programmed by maternal excessive fructose intake and environmental dioxin exposure.
- Published
- 2020
- Full Text
- View/download PDF
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