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Acinetobacter species are widely known opportunistic pathogens causing severe community and healthcare-associated infections. One such emerging pathogen, Acinetobacter colistiniresistens, is known to exhibit intrinsic resistance to colistin. We investigated the molecular characteristics of A. colistiniresistens strain C-214, isolated from the fecal sample of a healthy community member, as part of a cohort study being conducted in Segamat, Malaysia. Comparison of the whole genome sequence of C-214 with other A. colistiniresistens sequences retrieved from the NCBI database showed 95% sequence identity or more with many of the genome sequences representing that species. Use of the Galleria mellonella killing assay showed that C-214 was pathogenic in this model infection system. The strain C-214 had a colistin and polymyxin B MIC of 32 and 16 mg/L, respectively. Besides, it was resistant to cefotaxime, amikacin, and tetracycline and showed moderate biofilm-producing ability. Different genes associated with virulence or resistance to major classes of antibiotics were detected. We observed mutations in lpxA/C/D in C-214 and other A. colistiniresistens strains as probable causes of colistin resistance, but the biological effects of these mutations require further investigation. This study provides genomic insights into A. colistiniresistens, a potentially pathogenic bacterium isolated from a community member and notes the public health threat it may pose., (© 2023. Springer Nature Limited.)

Approximate 70% of cobra venom is composed of cytotoxin (CTX), which is responsible for the dermonecrotic symptoms of cobra envenomation. However, CTX is generally low in immunogenicity, and the antivenom is ineffective in attenuating its in vivo toxicity. Furthermore, little is known about its epitope properties for empirical antivenom therapy. This study aimed to determine the epitope sequences of CTX using the immunoinformatic analyses and epitope-omics profiling. A conserved CTX was used in this study to determine its T-cell and B-cell epitope sequences using immunoinformatic tools and molecular docking simulation with different Human Leukocyte Antigens (HLAs). The potential T-cell and B-cell epitopes were 'KLVPLFY,' 'CPAGKNLCY,' 'MFMVSTPTK,' and 'DVCPKNSLL.' Molecular docking simulations disclosed that the HLA-B62 supertype exhibited the greatest binding affinity towards cobra venom cytotoxin. The namely L7, G18, K19, N20, M25, K33, V43, C44, K46, N47, and S48 of CTX exhibited prominent intermolecular interactions with HLA-B62. The multi-enzymatic-limited-digestion/liquid chromatography-mass spectrometry (MELD/LC-MS) also revealed three potential epitope sequences as 'LVPLFYK,' 'MFMVS,' and 'TVPVKR'. From different epitope mapping approaches, we concluded four potential epitope sites of CTX as 'KLVPLFYK', 'AGKNL', 'MFMVSTPKVPV' and 'DVCPKNSLL'. Site-directed mutagenesis of these epitopes confirmed their locations at the functional loops of CTX. These epitope sequences are crucial to CTX's structural folding and cytotoxicity. The results concluded the epitopes that resided within the functional loops constituted potential targets to fabricate synthetic epitopes for CTX-targeted antivenom production., (© 2023. The Author(s).)

Antibiotic resistance is one of the biggest threats to global health resulting in an increasing number of people suffering from severe illnesses or dying due to infections that were once easily curable with antibiotics. Pseudomonas aeruginosa is a major pathogen that has rapidly developed antibiotic resistance and WHO has categorised this pathogen under the critical list. DNA aptamers can act as a potential candidate for novel antimicrobial agents. In this study, we demonstrated that an existing aptamer is able to affect the growth of P. aeruginosa. A computational screen for aptamers that could bind to a well-conserved and essential outer membrane protein, BamA in Gram-negative bacteria was conducted. Molecular docking of about 100 functional DNA aptamers with BamA protein was performed via both local and global docking approaches. Additionally, genetic algorithm analysis was carried out to rank the aptamers based on their binding affinity. The top hits of aptamers with good binding to BamA protein were synthesised to investigate their in vitro antibacterial activity. Among all aptamers, Apt31, which is known to bind to an antitumor, Daunomycin, exhibited the highest HADDOCK score and resulted in a significant (p < 0.05) reduction in P. aeruginosa growth. Apt31 also induced membrane disruption that resulted in DNA leakage. Hence, computational screening may result in the identification of aptamers that bind to the desired active site with high affinity., (© 2023. The Author(s).)

Epidural analgesia provides effective pain relief during labor. However, there is limited information on the factors associated with pregnant women's preferences for labor epidural analgesia (LEA) prior to labor onset. We performed a secondary analysis of a clinical trial to identify demographic characteristics, pain and psychological vulnerability factors associated with preferences for LEA. Pregnant women at ≥ 36 weeks' gestation prior to labor and delivery were recruited and given questionnaires on their LEA preferences, psychological and pain vulnerabilities. The primary outcome was the association between pre-delivery Edinburgh Postnatal Depression Scale (EPDS) with cut-off ≥ 10 and LEA preference. Of the 250 women recruited, 51.6% (n = 129) indicated "yes to LEA". Amongst those considering LEA as an option to reduce labor pain, women who preferred to use LEA (n = 129) indicated favorable or neutral opinion. Additionally, 68% (n = 82) from those "no to LEA" or "not sure about LEA" still gave either favorable or neutral opinion for LEA (p < 0.0001). The multivariate logistic regression analysis found that EPDS ≥ 10 (p < 0.01), occupation (p = 0.03), ethnicity (p < 0.01), state anxiety (p = 0.02), mode of current pregnancy (unplanned; planned, assisted; planned, natural; p = 0.03) and premenstrual anger/irritability before current pregnancy (p = 0.02) were associated with LEA preference. The findings may help to define the population that may require further education on considering LEA and allow early identification on different LEA preferences to provide patient centric care prior to labor and delivery., (© 2022. The Author(s).)

Perceived stress is a dimension of the maternal stress response, however little data is available on perceived stress levels and its associated psychological risk factors during labor. In this secondary data analysis from a prospective study evaluating epidural regimens, we investigated the potential associations between depressive symptomatology, anxiety, and pain catastrophizing with perceived stress during labor. Healthy nulliparous adult women with term singleton pregnancies requesting for epidural analgesia in early labor were included. Assessments were administered after epidural analgesia and adequate pain relief were achieved. Perceived stress (Perceived Stress Scale, PSS, high PSS ≥ 16), depressive symptomatology (Edinburgh Postnatal Depression Scale, EPDS, high EPDS ≥ 10), and pain catastrophizing (Pain Catastrophizing Scale, PCS, high total PCS ≥ 25) were assessed as categorical variables. Additionally, anxiety (State-trait Anxiety Inventory, STAI), PCS total and its subscales (rumination, magnification and helplessness) were analyzed as continuous variables. Univariate and multivariable logistic regression models were used to identify factors associated with high PSS. Of 801 women included, 411 (51.9%) had high PSS. High EPDS (OR 2.16, 95%CI 1.36-3.44), increasing trait anxiety (OR 1.17, 95%CI 1.14-1.20), and increasing pain magnification (OR 1.12, 95%CI 1.05-1.19) were independently associated with high PSS. Depressive symptomatology, trait anxiety, and pain magnification were associated with perceived stress during labor, providing impetus for future research aimed at detecting and alleviating stress and its psychological or pain association factors., (© 2021. The Author(s).)

Mitophagy is a selective form of autophagy involving the removal of damaged mitochondria via the autophagy-lysosome pathway. PINK1-Parkin-mediated mitophagy is one of the most important mechanisms in cardiovascular disease, cerebral ischemia-reperfusion (I/R) injury, and neurodegenerative diseases. In this study we conducted an image-based screening in YFP-Parkin HeLa cells to discover new mitophagy regulators from natural xanthone compounds. We found that garciesculenxanthone B (GeB), a new xanthone compound from Garcinia esculenta, induced the formation of YFP-Parkin puncta, a well known mitophagy marker. Furthermore, treatment with GeB dose-dependently promoted the degradation of mitochondrial proteins Tom20, Tim23, and MFN1 in YFP-Parkin HeLa cells and SH-SY5Y cells. We revealed that GeB stabilized PINK1 and triggered Parkin translocation to the impaired mitochondria to induce mitophagy, and these effects were abolished by knockdown of PINK1. Finally, in vivo experiments demonstrated that GeB partially rescued ischemia-reperfusion-induced brain injury in mice. Taken together, our findings demonstrate that the natural compound GeB can promote the PINK1-Parkin-mediated mitophagy pathway, which may be implicated in protection against I/R brain injury.

Metastasis causes the main lethality in esophageal cancer patient. Garcinol, a natural compound extracted from Gambogic genera, is a histone acetyltransferase (HAT) inhibitor that has shown anticancer activities such as cell cycle arrest and apoptosis induction. In this study, we investigated the effects of garcinol on the metastasis of esophageal cancer in vitro and in vivo. We found that garcinol (5-15 μM) dose-dependently inhibited the migration and invasion of human esophageal cancer cell lines KYSE150 and KYSE450 in wound healing, transwell migration, and Matrigel invasion assays. Furthermore, garcinol treatment dose-dependently decreased the protein levels of p300/CBP (transcriptional cofactors and HATs) and p-Smad2/3 expression in the nucleus, thus impeding tumor cell proliferation and metastasis. Knockdown of p300 could inhibit cell metastasis, but CBP knockdown did not affect the cell mobility. It has been reported that TGF-β1 stimulated the phosphorylation of Smad2/3, which directly interact with p300/CBP in the nucleus, and upregulating HAT activity of p300. We showed that garcinol treatment dose-dependently suppressed TGF-β1-activated Smad and non-Smad pathway, inhibiting esophageal cancer cell metastasis. In a tail vein injection pulmonary metastasis mouse model, intraperitoneal administration of garcinol (20 mg/kg) or 5-FU (20 mg/kg) significantly decreased the number of lung tumor nodules and the expression levels of Ki-67, p300, and p-Smad2/3 in lung tissues. In conclusion, our study demonstrates that garcinol inhibits esophageal cancer metastasis in vitro and in vivo, which might be related to the suppression of p300 and TGF-β1 signaling pathways, suggesting the therapeutic potential of Garcinol for metastatic tumors.

Lysosomes are the terminal organelles of the autophagic-endocytic pathway and play a key role in the degradation of autophagic contents. We previously reported that a natural compound oblongifolin C (OC) increased the number of autophagosomes and impaired the degradation of P62, most likely via suppression of lysosomal function and blockage of autophagosome-lysosome fusion. However, the precise mechanisms of how OC inhibits the lysosome-autophagy pathway remain unclear. In the present study, we investigated the effect of OC on transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, lysosomal function and autophagy. We showed that treatment with OC (15 μM) markedly enhanced the nuclear translocation of TFEB in HeLa cells, concomitantly reduced the interaction of TFEB with 14-3-3 proteins. We further demonstrated that OC caused significant inhibition of mTORC1 along with TFEB nuclear translocation, and OC-mediated TFEB nuclear translocation was dependent on mTORC1 suppression. Intriguingly, this increased nuclear TFEB was accompanied by reduced TFEB luciferase activity, increased lysosomal pH and impaired cathepsin enzyme activities. In HeLa cells, treatment with OC (7.5 μM) resulted in about 30% of cell death, whereas treatment with hydroxycitrate, a caloric restriction mimetic (20 μM) did not affect the cell viability. However, cotreatment with OC and hydroxycitrate caused significantly great cytotoxicity (>50%). Taken together, these results demonstrate that inhibition of lysosome function is mediated by OC, despite evident TFEB nuclear translocation.

Oblongifolin C (OC) and guttiferone K (GUTK) are two anticancer compounds extracted from Garcinia yunnanensis Hu, but they act by different mechanisms. In this study we investigated whether a combination of OC and GUTK (1:1 molar ratio) could produce synergistic anticancer effects against human colorectal cancer cells in vitro. For comparison, we also examined the anticancer efficacy of ethanol extracts from G yunnanensis fruit, which contain OC and GUTK up to 5%. Compared to OC and GUTK alone, the combination of OC and GUTK as well as the ethanol extracts more potently inhibited the cancer cell growth with IC 50 values of 3.4 μmol/L and 3.85 μg/mL, respectively. Furthermore, OC and GUTK displayed synergistic inhibition on HCT116 cells: co-treatment with OC and GUTK induced more prominent apoptosis than treatment with either drug alone. Moreover, the combination of OC and GUTK markedly increased cleavage of casapse-3 and PARP, and enhanced cellular ROS production and increased JNK protein phosphorylation. In addition, the combination of OC and GUTK exerted stronger effects under nutrient-deprived conditions than in complete medium, suggesting that autophagy played an essential role in regulating OC- and GUTK-mediated cell death. OC and GUTK are the main components that contribute to the anticancer activity of G yunnanensis and the compounds have apoptosis-inducing effects in HCT116 cells in vitro.

Idiosyncratic drug-induced hepatotoxicity is a major cause of liver damage and drug pipeline failure, and is difficult to study as patient-specific features are not readily incorporated in traditional hepatotoxicity testing approaches using population pooled cell sources. Here we demonstrate the use of patient-specific hepatocyte-like cells (HLCs) derived from induced pluripotent stem cells for modeling idiosyncratic hepatotoxicity to pazopanib (PZ), a tyrosine kinase inhibitor drug associated with significant hepatotoxicity of unknown mechanistic basis. In vitro cytotoxicity assays confirmed that HLCs from patients with clinically identified hepatotoxicity were more sensitive to PZ-induced toxicity than other individuals, while a prototype hepatotoxin acetaminophen was similarly toxic to all HLCs studied. Transcriptional analyses showed that PZ induces oxidative stress (OS) in HLCs in general, but in HLCs from susceptible individuals, PZ causes relative disruption of iron metabolism and higher burden of OS. Our study establishes the first patient-specific HLC-based platform for idiosyncratic hepatotoxicity testing, incorporating multiple potential causative factors and permitting the correlation of transcriptomic and cellular responses to clinical phenotypes. Establishment of patient-specific HLCs with clinical phenotypes representing population variations will be valuable for pharmaceutical drug testing., Competing Interests: Ravindran Kanesvaran has received research funding from Sanofi and is on advisory board of Pfizer, Astellas and Bayer. Hanry Yu has ownership in and is on advisory board of InvitroCue Pte Ltd and has received research funding from Janssen. Min-Han Tan has received research funding from Pfizer. Yukti Choudhury and Min-Han Tan have filed a patent filed for a patent involving molecular diagnostics in renal cell carcinoma. The remaining authors have declared no competing financial interests.

A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1-2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V-Z (3-7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry. Experimental and calculated ECD spectra were used to determine the absolute configurations. The results of wound healing and transwell migration assay showed that oblongixanthones D (1), E (2), and oblongifolin L (9) have the ability to inhibit cancer cell migration in lower cytotoxic concentrations. Western blotting results showed that these compounds exhibited an anti-metastasis effect mainly through downregulating RAF protein levels. In addition, 2 and 9 could inhibit phospho-MEK and phospho-ERK at downstream. Moreover, 1, 2, and 9 could inhibit snail protein level, suggesting that they could regulate the EMT pathway.

Aim: The nuclear factor erythroid 2-related factor 2 (NRF2) acts through the antioxidant response element (ARE) to regulate the expression of many detoxifying and antioxidant genes responsible for cytoprotective processes. We previously reported that Schisandrol B (SolB) isolated from Schisandra sphenanthera produced a protective effect against acetaminophen (APAP)-induced liver injury. In this study we investigated whether the NRF2/ARE signaling pathway was involved in this hepato-protective effect., Methods: Male C57BL/6 mice were treated with SolB (200 mg · kg(-1) · d(-1), ig) for 3 d before injection of APAP (400 mg/kg, ip). Serum and liver tissue samples were collected 6 h later. The mRNA and protein expression were measured using qRT-PCR and Western blot assay, respectively. The activation of NRF2 was examined in HepG2 cells using luciferase reporter gene assay., Results: SolB pretreatment significantly alleviated the hepatic injury (large patchy necrosis and hyperemia of the hepatic sinus), the increase of serum AST, ALT levels and hepatic MDA contents, and the decrease of liver and mitochondrial glutathione levels in APAP-treated mice. Furthermore, SolB pretreatment significantly increased nuclear accumulation of NRF2 and increased hepatic expression of NRF2 downstream proteins, including GCLC, GSR, NQO1, GSTs, MRP2, MRP3 and MRP4 in APAP-treated mice. Moreover, treatment with SolB (2.5-20 μmol/L) dose-dependently increased the activity of NRF2 reporter gene in HepG2 cells., Conclusion: SolB exhibits a remarkable protective effect against APAP-induced hepatotoxicity, partially via activation of the NRF2/ARE pathway and regulation of NRF2 target genes, which induce detoxification and increase antioxidant capacity.

Nonradiative relaxation of high-energy excited states to the lowest excited state in chlorophylls marks the first step in the process of photosynthesis. We perform ultrafast transient absorption spectroscopy measurements, that reveal this internal conversion dynamics to be slightly slower in chlorophyll B than in chlorophyll A. Modeling this process with non-adiabatic excited state molecular dynamics simulations uncovers a critical role played by the different side groups in the two molecules in governing the intramolecular redistribution of excited state wavefunction, leading, in turn, to different time-scales. Even given smaller electron-vibrational couplings compared to common organic conjugated chromophores, these molecules are able to efficiently dissipate about 1 eV of electronic energy into heat on the timescale of around 200 fs. This is achieved via selective participation of specific atomic groups and complex global migration of the wavefunction from the outer to inner ring, which may have important implications for biological light-harvesting function.

Purpose: To assess the outcome of silicone oil removal after rhegmatogenous retinal detachment (RRD) surgery, and to compare results of a two-port (infusion-extraction) versus a three-port (full vitrectomy) approach., Methods: Primary outcome measure was the rate of redetachment. Secondary outcome measures were visual acuity, rate of intraoperative and postoperative epiretinal membrane removal and complications., Results: We included 147 consecutive cases. There were 15 cases of giant retinal tear, 26 cases of RRD without proliferative vitreoretinopathy (PVR) and 106 cases of RRD with PVR. The overall redetachment rate after silicone oil removal was 17.7%. In the group treated with the two-port technique (n=95), the retina redetached in 16 cases (16.8%), and in the group treated with the three-port technique (n=52), redetachment occurred in 10 cases (19.2%). This difference was not statistically significant (P=0.717; χ (2)-test). There was a significantly higher redetachment rate in cases with a short oil tamponade duration of <2 months., Conclusion: We reconfirm a relatively high redetachment rate after silicone oil removal. The risk of redetachment is not lower with the three-port compared with the two-port approach.

Microelectronic circuits/arrays produced via high-speed printing instead of traditional photolithographic processes offer an appealing approach to creating the long-sought after, low-cost, large-area flexible electronics. Foremost among critical enablers to propel this paradigm shift in manufacturing is a stable, solution-processable, high-performance semiconductor for printing functionally capable thin-film transistors - fundamental building blocks of microelectronics. We report herein the processing and optimisation of solution-processable polymer semiconductors for thin-film transistors, demonstrating very high field-effect mobility, high on/off ratio, and excellent shelf-life and operating stabilities under ambient conditions. Exceptionally high-gain inverters and functional ring oscillator devices on flexible substrates have been demonstrated. This optimised polymer semiconductor represents a significant progress in semiconductor development, dispelling prevalent skepticism surrounding practical usability of organic semiconductors for high-performance microelectronic devices, opening up application opportunities hitherto functionally or economically inaccessible with silicon technologies, and providing an excellent structural framework for fundamental studies of charge transport in organic systems.

Purpose: To assess the additional value of blood culture bottles (BCBs) in the diagnosis of endophthalmitis by comparing its culture yield with that of conventional media (CM)., Design: Retrospective consecutive case series., Methods: We included patients who were treated between January 2001 and January 2010 for clinically suspected endophthalmitis of any etiology, and had vitreous specimens cultivated in both BCB and CM., Results: Specimens from 85 eyes from 85 patients were included. The culture yield of BCB was 69%, and that of CM was 72% (difference not significant). Adding the results of BCB improved the yield of CM significantly by 13%, resulting in a combined yield of 81%. The sensitivity of detection of Haemophilus influenzae in BCB seemed lower compared with CM, possibly due to the lack of growth factors in the BCB. There was no difference in yield between specimens obtained by tap or by vitrectomy., Conclusion: In contrast with earlier reports, we did not find BCB superior to CM. The combined use of BCB and CM increased the pathogen detection rate significantly and should therefore be considered as the microbiological method of choice in the work-up of endophthalmitis.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is an important hematopoietic growth factor and immune modulator. GM-CSF also has profound effects on the functional activities of various circulating leukocytes. It is produced by a variety of cell types including T cells, macrophages, endothelial cells and fibroblasts upon receiving immune stimuli. Although GM-CSF is produced locally, it can act in a paracrine fashion to recruit circulating neutrophils, monocytes and lymphocytes to enhance their functions in host defense. Recent intensive investigations are centered on the application of GM-CSF as an immune adjuvant for its ability to increase dendritic cell (DC) maturation and function as well as macrophage activity. It is used clinically to treat neutropenia in cancer patients undergoing chemotherapy, in AIDS patients during therapy, and in patients after bone marrow transplantation. Interestingly, the hematopoietic system of GM-CSF-deficient mice appears to be normal; the most significant changes are in some specific T cell responses. Although molecular cloning of GM-CSF was carried out using cDNA library of T cells and it is well known that the T cells produce GM-CSF after activation, there is a lack of systematic investigation of this cytokine in production by T cells and its effect on T cell function. In this article, we will focus mainly on the immunobiology of GM-CSF in T cells.