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Chitosan (Ch) is one of the most commonly used natural biomaterials. Osteodifferentiation of mesenchymal stem cells (MSCs) on Ch has drawn extensive interest. Hydroxyapatite (HA) is a component of skeleton and teeth with good biocompatibility. Combination with HA may be a good method to modify Ch to facilitate cellular behaviors and functions on it. In this study, Ch/HA film was prepared and characterized. Its potential to benefit cellular behaviors and osteodifferentiation of MSCs was evaluated. Resultantly, physical properties of composite Ch/HA, including water-in-air contact angle, tensile strength, elastic modulus, and breaking elongation were favorably modified. In cellular culture medium, Ch/HA films absorbed more Ca2+ than Ch films, and more HA crystalline growths on Ch/HA films. 3-(4,5-Dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and morphological features showed better proliferation and adhesion of MSCs on Ch/HA films. Osteodifferentiation of MSCs on Ch/HA was promoted, indicated by modified transcription level of osteocalcin, osteopontin, collagen I, alkaline phosphatase (ALP), and induced ALP activity. These data suggest biocompatibility of Ch is modified after being blended with HA, which promotes osteodifferentiation of MSCs. This can be a promising approach to modify Ch for its applications in bone tissue engineering. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 1202-1209, 2014. [ABSTRACT FROM AUTHOR]

The recombinant adeno-associated virus 8 (rAAV8) vector is a widely used tool in basic research and clinical trials. The cytomegalovirus immediate-early enhancer/chicken β-actin (CAG) promoter is a synthetic promoter used in adenoviral constructs with a wide spectrum and notable efficiency. The thyroxine binding globulin (TBG) promoter is a liver-specific promoter, which directs transgene expression in hepatocytes. However, the transduction efficiency of the rAAV vector is dependent on both the administration routes and the promoter elements. In the present study, the transduction efficiency in the liver following intraperitoneal (IP) and intravenous (IV) injections of rAAV8 with the CAG, TBG669 and TBG410 promoters was compared. Enhanced green fluorescent protein (EGFP) expression was used as the biomarker to indicate efficiency. Among the three different promoters, CAG exhibited the highest efficiency from both IV and IP injections. Following IV administration, EGFP expression, induced by the CAG promoter, was 67-fold higher compared with that in the TBG410 promoter group and 26-fold higher compared with that in the TBG669 promoter group. EGFP protein expression was higher with IV injection compared with that for IP injection for both the CAG and TBG669 promoters (P<0.05). With the CAG promoter, EGFP protein expression was 1.5-fold higher with the use of IV injection than with IP injection. With the TBG410 promoter, no differences were observed between the two administrations. In conclusion, these findings demonstrated that the CAG promoter was much more efficient at driving gene expression in the liver compared with that for the TBG promoters in rAAV8. In addition, IP administration produced comparable efficiency for gene delivery via the rAAV8 vector, particularly with the promoter TBG410. [ABSTRACT FROM AUTHOR]

Nitryl chloride (ClNO 2 ) is a key precursor of chlorine radicals, influencing atmospheric oxidation and secondary pollutants formation. Few studies have examined the ClNO 2 chemistry from the perspective of the planetary boundary layer. Here, we conducted a vertically resolved investigation of ClNO 2 at six heights (ranging from 5 to 335 m) on a 356 m tower in the Pearl River Delta, China, during winter 2021. Nocturnal ClNO 2 is notably lower at the surface than the upper layers, with the nocturnal median concentration at 220 m (51 parts per trillion by volume, pptv) being approximately three times higher than that recorded in the surface layer (16 pptv). Observation-constrained box model simulations show that the NO gradients primarily account for the vertical disparities. Compared to the hydroxyl radical (OH) production via the nitrous acid and ozone photolysis, ClNO 2 photolysis contributes to radical formation by 3.8% (1.8%) at 220 m (5 m) in the morning (07:00-08:00), indicates the enhanced significance of ClNO 2 chemistry aloft compared with the ground, and may cause the underestimation of ClNO 2 photolysis impacts if solely relying on surface measurements. We highlight that more field studies are needed to elucidate ClNO 2 chemistry across the boundary layer.

Background/aims: Dexamethasone (DEX) is a widely used exogenous therapeutic glucocorticoid in clinical settings. Its long-term use leads to many side effects. However, its effect on metabolic disorders in individuals on a high-fat diet (HFD) remains poorly understood., Methods: In this study, HFD-fed mice were intraperitoneally injected with DEX 2.5 mg/kg/day for 30 days. Lipid metabolism, adipocyte proliferation, and inflammation were assayed using typical approaches., Results: DEX increased the epididymal fat index and epididymal adipocyte size in HFD-fed mice. The number of epididymal adipocytes with diameters > 70 μm accounted for 0.5% of the cells in the control group, 30% of the cells in the DEX group, 19% of the cells in the HFD group, and 38% of all the cells in the D+H group. Adipocyte proliferation in the D+H group was inhibited by DEX treatment. Adipocyte enlargement in the D+H group was associated with increased the lipid accumulation but not the adipocyte proliferation. In contrast, the liver triglyceride and total cholesterol levels and their metabolism were downregulated by the same treatment, indicating the therapeutic potential of DEX for nonalcoholic fatty liver disease., Conclusion: DEX synergizes with HFD to promote lipid deposition in adipose tissues. A high risk of obesity development in patients receiving HFD and DEX treatment is suggested.

Background/aim: Depression is associated with metabolic disorders, including non-alcoholic fatty liver disease (NAFLD). However, the mechanisms underlying the interaction between them are still poorly known., Materials and Methods: In this study, mice on a choline deficiency, L-amino acid-defined, high-fat diet (CDAHFD) developing steatosis were challenged with chronic restraint stress (CRS), a protocol widely used to induce depression. The development of depression and steatosis was evaluated using histopathology analysis, ELISA, q-PCR and Western Blot., Results: The contribution of the activated HPA axis to hepatic steatosis progress was fully established, which was validated using a hepatocyte model. Histopathological and biochemical analysis indicated that steatosis was exacerbated by CRS challenge, and behavioral tests indicated that the mice developed depression. Among the screened endocrinal pathways, the hypothalamic-pituitary-adrenal (HPA) axis was significantly activated and the synergistic effect of CDAHFD and CRS in activating the HPA axis was observed. In the hypothalamus, expression of corticotropin-releasing hormone (CRH) was increased by 86% and the protein levels of hypothalamic CRH were upregulated by 25% to 33% by CRS treatment. Plasma CRH levels were elevated by 45-56% and plasma adrenocorticotropic hormone (ACTH) levels were elevated by 29-58% by CRS treatment. In the liver, target genes of the HPA axis were activated, accompanied by disruption of the lipid metabolism and progression of steatohepatitis. The lipid metabolism in the Hepa1-6 cell line treated with endogenous corticosterone (CORT) was in accordance with the aforementioned in vivo responses., Conclusion: Depression aggravated hepatic steatosis in CDAHFD-fed mice by activating the HPA axis. The risk of NAFLD development should be fully considered in depressive patients and improvement of psychotic disorders could be an etiological treatment strategy for them., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Objective: To analyze the clinical effect of high-flow nasal cannula (HFNC) oxygen therapy combined with naloxone on severe respiratory failure (SRF) in older adult patients., Methods: We enrolled 96 older adult patients with SRF who were admitted to Hai'an People's Hospital between February 2019 and March 2022. The patients were divided into two groups: the control group (treated with non-invasive positive pressure ventilation combined with naloxone) and the observation group (treated with HFNC oxygen therapy combined with naloxone). The blood gas measurement, respiratory rate (RR), St. George's Respiratory Questionnaire (SGRQ) score, Clara cell secreted protein (CC16) level, tumor necrosis factor-alpha (TNF-α) level, interleukin-1 (IL-1) level, length of intensive care unit (ICU) stay, tracheal intubation rate, and 28-day mortality rate were compared between the groups., Results: Blood gas measurement or RR did not differ significantly between the groups ( P >0.05). The observation group showed improved outcome, including reduced partial pressure of CO 2 , RR, and pH, and increased partial pressure of O 2 (PaO 2 ), PaO 2 /fraction of inspired O 2 ratio, and O 2 saturation after treatment ( P <0.05). Additionally, the observation group exhibited lower TNF-α level, IL-1 level, and SGRQ score, and higher CC16 level ( P <0.05). The length of ICU stay, tracheal intubation rate, and 28-day mortality rate were lower in the observation group ( P <0.05)., Conclusions: HFNC oxygen therapy combined with naloxone in older adult patients with SRF could improve blood gas results, disease duration, tracheal intubation rate, and 28-day mortality rate. This may occur through regulation of TNF-α, IL-1, and CC16 expression., Competing Interests: None., (AJTR Copyright © 2023.)

Objective: To analyze the clinical characteristics and risk factors of early acute liver injury in patients with heat stroke (HS), and to provide basis for early identification of HS-related liver injury and its pathogenesis in clinical practice., Methods: The clinical data of patients with HS admitted to the department of critical care medicine of Haian People's Hospital from June 2015 to August 2022 were retrospectively analyzed. The patients with HS were divided into early liver injury group and early non-liver injury group according to the occurrence of acute liver injury within 24 hours of admission. The differences of basic data, clinical data, laboratory indexes and clinical outcomes of the two groups were analyzed. Logistic regression was used to analyze the risk factors for early HS-related acute liver injury, and receiver operator characteristic (ROC) curves were drawn to evaluate their value in predicting the occurrence of early HS-related acute liver injury., Results: A total of 76 patients with HS were enrolled, and 46 patients with acute liver injury, accounting for 60.53%. In the early liver injury group, 14 patients (30.43%) had elevated aminotransferase alone, 9 patients (19.57%) had elevated total bilirubin (TBil) alone, and 23 patients (50.00%) had elevated both aminotransferase and TBil. Among the patients with elevated aminotransferases, 24 patients (64.87%) had mild elevation, 5 patients (13.51%) had moderate elevation, 8 patients (21.62%) had severe elevation. Compared with the early non-liver injury group, acute physiology and chronic health evaluation II (APACHE II), sequential organ failure assessment (SOFA), arterial blood lactate (Lac), interleukin-6 (IL-6), procalcitonin (PCT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), TBil, γ-gamma glutamyl transferase (γ-GGT), lactate dehydrogenase (LDH), creatine kinase (CK), MB isoenzyme of creatine kinase (CK-MB), cardiac troponin I (cTnI), myoglobin (MYO), N-terminal B-type pro-brain natriuretic peptide (NT-proBNP), prothrombin time (PT), activated partial thromboplastin time (APTT), D-dimer in the early liver injury group were significantly increased, while platelet count (PLT) were significantly decreased within 24 hours after admission, the 28-day mortality was significantly increased [28.26% (13/46) vs. 6.67% (2/30)], and the differences were statistically significant (all P < 0.05). Univariate Logistic regression analysis showed that APACHE II score, SOFA score, PLT, Lac, IL-6, PCT, γ-GGT, LDH, CK, CK-MB, cTnI, MYO, PT, APTT, D-dimer were risk factors of early HS-related acute liver injury (all P < 0.05). Multivariate Logistic regression analysis showed that PLT, IL-6, and LDH were independent risk factors of early HS-related acute liver injury [odds ratio (OR) and 95% confidence interval (95%CI) were 0.986 (0.974-0.998), 1.027 (1.012-1.041), and 1.002 (1.000-1.004), all P < 0.05]. The ROC curve analysis showed that the area under the ROC curve (AUC) of PLT, IL-6 and LDH for predicting the occurrence of early HS-related acute liver injury was 0.672 (95%CI was 0.548-0.797), 0.897 (95%CI was 0.824-0.971) and 0.833 (95%CI was 0.739-0.927), respectively. IL-6 had the highest predictive value for early HS-related liver injury. When the optimal diagnostic threshold of IL-6 was 48.25 ng/L, the sensitivity was 95.7%, the specificity was 73.3%, and the predictive value of PLT was the lowest., Conclusions: The early HS-related liver injury is mainly manifested as the simultaneous elevation of aminotransferase and TBil, and most of cases are mild liver injury. PLT, IL-6 and LDH are independent risk factors of early HS-related acute liver injury.

Platelet hyperreactivity and increased atherothrombotic risk are specifically associated with dyslipidemia. Peroxisome proliferator-activated receptor alpha (PPARα) is an important regulator of lipid metabolism. It has been suggested to affect both thrombosis and hemostasis, yet the underlying mechanisms are not well understood. In this study, the role and mechanism of PPARα in platelet activation and thrombosis related to dyslipidemia were examined. Employing mice with deletion of PPARα (Pparα-/-), we demonstrated that PPARa is required for platelet activation and thrombus formation. The effect of PPARα is critically dependent on platelet dense granule secretion, and is contributed by p38MAPK/Akt, fatty acid b-oxidation, and NAD(P)H oxidase pathways. Importantly, PPARα and the associated pathways mediated a prothrombotic state induced by a high-fat diet and platelet hyperactivity provoked by oxidized low density lipoproteins. Platelet reactivity was positively correlated with the levels of expression of PPARα, as revealed by data from wild-type, chimeric (Pparα+/-), and Pparα-/- mice. This positive correlation was recapitulated in platelets from hyperlipidemic patients. In a lipid-treated megakaryocytic cell line, the lipid-induced reactive oxygen species-NF-kB pathway was revealed to upregulate platelet PPARα in hyperlipidemia. These data suggest that platelet PPARα critically mediates platelet activation and contributes to the prothrombotic status under hyperlipidemia.

Objective: To observe the effect of early intervention bundle on clinical prognosis of patients with latent/overt septic shock in emergency department and analyze the risk factors for mortality., Methods: Patients with latent and overt septic shock admitted to the North Hospital of Huashan Hospital Affiliated to Fudan University from January 2018 to December 2019 were retrospectively analyzed and divided into latent shock group and overt shock group. The gender, age, main infection site, the time of shock diagnosis, the indicators of early (3-hour) intervention bundle, 6-hour compliance rate of intervention bundle, the remission time and 28-day prognosis were observed. Logistic regression analysis was used to identify risk factors for 28-day mortality. Receiver operating characteristic (ROC) curve was used to analyze its prognostic value., Results: Totally 181 patients were included in the analysis. There were 102 cases in the latent shock group, and 28-day mortality was 15.69% (16 cases); 79 cases in the overt shock group, and 28-day mortality was 31.65% (25 cases). Compared with the latent shock group, patients in overt shock group had higher compliance rate of early intervention bundle (93.67% vs. 58.82%), higher blood lactate acid at admission [Lac (mmol/L): 7.09±2.08 vs. 5.69±1.27], higher compliance rate of blood culture before antibiotics (93.67% vs. 63.73%), higher proportion of antibiotics use at the first and second hours (45.57% vs. 31.37%, 54.43% vs. 33.33%), higher proportion of rapid fluid resuscitation at the first hour (crystal liquid: 59.49% vs. 11.76%, crystal fluid combined with human serum albumin: 40.51% vs. 0%), and higher proportion of vasoactive use at the first hour (100% vs. 9.80%). The stable time was significantly prolonged (days: 4.40±1.35 vs. 1.49±0.55), while the onset time (days: 1.47±0.97 vs. 2.95±1.61), the time of diagnosis (minutes: 31.30±12.54 vs. 79.15±13.81), 6-hour lactate clearance [(50.27±21.53)% vs. (61.82±13.12)%], the proportion of antibiotics use at the third hour (0% vs. 35.29%), the proportion of rapid fluid resuscitation at the second and third hour (second hour crystal liquid: 0% vs. 60.78%, second hour crystal fluid combined with human serum albumin: 0% vs. 14.71%, third hour crystal liquid: 0% vs. 12.75%), 6-hour compliance rate of the standard of central venous blood saturation (ScvO 2 , 60.76% vs. 78.43%) and the success rate of treatment (28-day mortality: 31.65% vs. 15.69%) were lower than those of the latent shock group (all P < 0.05). Ten patients with latent shock developed into overt shock within 24 hours after admission. All patients with overt shock needed vasoactive drugs to maintain mean arterial pressure (MAP) ≥ 65 mmHg (1 mmHg = 0.133 kPa). Compared with the survival patients, the Lac (mmol/L: 7.59±2.27 vs. 5.92±1.24) and the proportion of vasoactive drugs use (65.85% vs. 44.29%) were significantly increased in the death patients, while the 6-hour lactate clearance [(46.58±15.83)% vs. (59.60±17.92)%], the proportion of antibiotics use in the third hour (4.88% vs. 24.29%), and 6-hour compliance rate of urine volume and ScvO 2 (56.10% vs. 82.86%, 43.90% vs. 78.57%) were significantly decreased (all P < 0.05). Binary Logistic regression analysis showed that Lac at admission, 6-hour lactate clearance, the use of antibiotics at the third hour, rapid fluid resuscitation at the first hour, and 6-hour compliance rate of ScvO 2 were independent risk factors for 28-day mortality [odds ratio (OR) was 1.618, 0.021, 0.100, 0.307 and 3.018, all P < 0.05]. ROC curve analysis showed that the Lac at admission had the highest predictive value for 28-day mortality, the area under the ROC curve (AUC) was 0.706; followed by 6-hour compliance rate of ScvO 2 (AUC was 0.673)., Conclusions: Patients with latent/overt septic shock need early diagnosis and intervention bundle to improve the 6-hour blood lactate clearance and 6-hour compliance rate of ScvO 2 and reduce the mortality.

Background: Concurrence of high glucose or diabetes in patients with dyslipidemia is presenting major challenges for clinicians. Although sporadically reported, a rational basis for the use of fibrates for the treatment of dyslipidemia with concurrent metabolic syndrome has not been established., Methods: In this study, wild-type (WT) and Ppara-null (KO) mice were fed a serial gemfibrozil- and fenofibrate-containing diet under the same experimental conditions for 14 days. Glucose level in the blood, glycogen storage in the liver tissues, and the potential toxic responses were assayed. Genes involved in glucose metabolism were determined by quantitative polymerase chain reaction analysis., Results: Both the blood glucose level and the glycogen content in the liver were down-regulated by gemfibrozil but not by fenofibrate in WT mice, in a dose-dependent manner. This decrement did not occur in KO mice for either fibrate agent. Secondary regulation on the transcription of pyruvate kinase, and gluconolactonase were observed following gemfibrozil treatment, which was differential between WT mice and KO mice., Conclusions: Gemfibrozil, not fenofibrate, down-regulates systemic glucose level and glycogen storage in the liver dependent on PPARα, suggesting its potential value for treatment of dyslipidemia with concurrent diabetes or high glucose levels.

Background: VGF (nonacryonimic) and phosphatidylinositol 3-kinase (PI3K)/AKT (also known as protein kinase B, PKB)/mammalian target of rapamycin (mTOR) signaling play pivotal roles in depression. However, whether phosphatidylinositol 3-kinase/AKT/mTOR signaling-mediated VGF participates in rapid-acting antidepressant-like actions of GLYX-13 is unclear., Methods: Herein, we evaluated the effects of acute treatment of GLYX-13 (0.5, 5, and 10mg/kg, i.p.) in the forced swim test. In addition, we assessed whether the acute treatment with GLYX-13 reverses the depressive-like behaviors induced by chronic unpredictable mild stress. Furthermore, we determined whether the Vgf knockdown in hippocampus of mice blocks the effects of GLYX-13. Moreover, we also demonstrated the effects of intra-hippocampus infusion of LY294002 (10 nmol/side), a specific phosphatidylinositol 3-kinase inhibitor prior to the treatment of GLYX-13 in the forced swim test. Lastly, whether alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor and mTOR activation involves in the antidepressant-like effects of GLYX-13 was examined., Results: Our results shown that GLYX-13 dose-dependently reversed the depressive-like behaviors in forced swim test. Additionally, GLYX-13 significantly reversed the downregulation of phosphorylation of AKT, mTOR, and eukaryotic elongation factor 2 as well as VGF induced by chronic unpredictable mild stress in hippocampus. Further, Vgf knockdown in hippocampus of mice significantly blocked the rapid-acting antidepressant-like effects and upregulation on phosphatidylinositol 3-kinase/AKT/mTOR/VGF signaling of GLYX-13. Moreover, intra-hippocampus infusion of LY294002 significantly abolished the antidepressant-like effects and upregulation on phosphatidylinositol 3-kinase/AKT/mTOR/VGF signaling of GLYX-13. Finally, antidepressant-like effects of GLYX-13 required AMPA receptor and mTOR activation, as evidenced by the ability of NBQX and rapamycin to block the effects of GLYX-13, respectively., Conclusions: Our results suggest that phosphatidylinositol 3-kinase/AKT/mTOR signaling-mediated VGF in hippocampus may be involved in the antidepressant-like effects of GLYX-13., (© The Author 2015. Published by Oxford University Press on behalf of CINP.)

Fenofibrate is a prototypical agonist of peroxisome proliferator-activated receptor alpha (PPARalpha) which is well known to be associated with species related carcinogenesis. Important species differences have been reported in its metabolism and elimination pattern. Its new metabolites have been revealed in Cynomolgus monkeys and Sprague-Dawley rats. However in beagle dogs, several polar metabolites of fenofibrate have not been identified yet. In this study, beagle dogs were orally dosed with fenofibrate mixed with feeds. Urine and plasma samples were collected and subject to LC-MS/MS by comparison with authentic compounds and confirmed using an API 4000 Q-TRAP system. In vitro cultured primary hepatocytes were used to reveal metabolic pathways and confirm the data in vivo. Seven new metabolites of fenofibrate in dogs were identified, and their metabolic pathways were revealed. Fenofibrate in beagle dogs was found to be more prone to be metabolized into other secondary metabolites than fenofibric acid, compared with that in rats.

A new method is developed for the determination of acrylamide in starch-based foods. The method included the extraction of acrylamide with water, defatting with hexane, derivatization with potassium bromate (KBrO(3)) and potassium bromide (KBr), liquid-liquid extraction with ethyl acetate-hexane (4:1), and concentration. The final analyte (2-bromopropenamide, 2-BPA) is analyzed by high-performance liquid chromatography coupled with diode array detection for quantification and by gas chromatography coupled to mass spectrometry for confirmation. The chromatographic analysis is performed on an ODS-3 C(18) column, and good retention and peak response of acrylamide are achieved under the optimal conditions. The limit of detection and quantitation are estimated to be 15 and 50 μg/kg, respectively. The recoveries of acrylamide from the commercial samples are spiked at levels of 50-1000 μg/kg, and range between 89.6 and 102.0%. These results show that this method should be regarded as a new, low-cost, and robust alternative for conventional investigation of acrylamide.

Gemfibrozil is the most myotoxic fibrate drug commonly used for dyslipidemia, but the mechanism is poorly understood. The current study revealed that gemfibrozil inhibits myoblast differentiation through the regulation of intracellular calcium ([Ca(2+)]i) as revealed in L6 myoblasts by use of laser scan confocal microscopy and flow cytometry using Fluo-4 AM as a probe. Gemfibrozil at 20-400 μM, could regulate [Ca(2+)]i in L6 cells in a biphasic manner, and sustained reduction was observed when the concentration reached 200 μM. Inhibition of L6 differentiation by gemfibrozil was concentration-dependent with maximal effect noted between 200 and 400 μM, as indicated by creatine kinase activities and the differentiation index, respectively. In differentiating L6 myoblasts, gemfibrozil at concentrations below 400 μM led to no significant signs of apoptosis or cytotoxicity, whereas differentiation, inhibited by 200 μM gemfibrozil, was only partially recovered. A good correlation was noted between gemfibrozil concentrations that regulate [Ca(2+)]i and inhibit L6 myoblasts differentiation, and both are within the range of total serum concentrations found in the clinic. These data suggest a potential pharmacodynamic effect of gemfibrozil on myogenesis as a warning sign, in addition to the complex pharmacokinetic interactions. It is also noteworthy that mobilization of [Ca(2+)]i by gemfibrozil may trigger complex biological responses besides myocyte differentiation. Information revealed in this study explores the mechanism of gemfibrozil-induced myotoxicity through the regulation of intracellular calcium.