SARS-CoV-2 omicron variant clearance delayed in breakthrough cases with elevated fasting blood glucose.

BACKGROUND: Omicron variant (B.1.1.529) is a dominant variant worldwide. However, the risk factors for Omicron variant clearance are yet unknown. The present study aimed to investigate the risk factors for early viral clearance of Omicron variant in patients with a history of inactivated vaccine injection. METHODS: Demographic, clinical, and epidemiological data from 187 patients were collected retrospectively during the Omicron variant wave. RESULTS: 73/187 and 114/187 patients were administered two and three doses of vaccine, respectively. The median duration of SARS-CoV-2 RNA positivity was 9 days, and the difference between patients with two and three vaccine injections was insignificant (P = 0.722). Fever was the most common symptom (125/187), and most patients (98.4%) had a fever for < 7 days. The RNA was undetectable in 65/187 patients on day 7. Univariable logistic analysis showed that baseline glucose, uric acid, lymphocytes count, platelet count, and CD4+ T lymphocyte count were associated with SARS-CoV-2 RNA-positivity on day 7. Multivariable analysis showed that glucose ≥ 6.1 mmol/L and CD4+T lymphocytes count were independent risk factors for RNA positivity on day 7. 163/187 patients had an undetectable RNA test on day 14, and uric acid was the only independent risk factor for RNA positivity. Moreover, baseline glucose was negatively correlated with uric acid and CD4+ and CD8+ T cell count, while uric acid was positively correlated with CD4+ and CD8+ T cell count. CONCLUSIONS: Omicron variant clearance was delayed in breakthrough cases with elevated fasting blood glucose, irrespective of the doses of inactivated vaccine.

Dynamics of a colloid-in-tube host-guest system.

Originated from supramolecular chemistry, the host-guest concept is generalized and appreciated across the fields of enzyme catalysis, biological channel conduction, and carbon nanotube transport, to name a few. Despite the extensive study of host-guest thermodynamics, it is still a fundamental challenge to directly measure its dynamics in real-space and real-time. Herein we approach such dynamics by direct imaging and tracking in a colloid-in-tube system, where self-assembled tubes are the hosts and sphere particles are the guests. The key difference from a previously reported static 1D confinement is that the present tubes are thermally actuated and capable of translations and rotations. It is the host tube thermal motions that impose a number of anomalies to guest particle dynamics including broadened distribution perpendicular to the tube, enhanced diffusion parallel to the tube phenomenologically resembling the rapid flow in ion channels or carbon nanotubes, and induced long-range particle-particle attraction analogous to capillary condensation. This work in the colloidal system is of wide implications for host-guest systems that are naturally embedded in thermal fluctuations such as transmembrane ion channels and carbon nanotube arrays in a soft matrix.

Serum NGAL Is Superior to Cystatin C in Predicting the Prognosis of Acute-on-Chronic Liver Failure.

INTRODUCTION AND AIM: Acute-on-chronic liver failure (ACLF) is a syndrome with high short-term mortality, and predicting the prognosis is challenging. This study aimed to compare the performance of neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C (CysC) in predicting the 90-day mortality in patients with hepatitis B virus (HBV)-associated ACLF (HBV-ACLF). MATERIALS AND METHODS: This prospective, observational study enrolled 54 patients with HBV-ACLF. The serum NGAL and CysC levels were determined. A multivariate logistic regression analysis was used to analyze the independent risk factors of mortality. RESULTS: Serum NGAL, but not CysC, was found to significantly correlate with the total bilirubin, international normalized ratio, and model for end-stage liver disease (MELD). Serum NGAL [odds ratio (OR), 1.008; 95% confidence interval (CI), 1.004-1.012; P < 0.01], but not CysC, was an independent risk factor for developing hepatorenal syndrome. Moreover, NGAL (OR, 1.005; 95% CI, 1.001-1.010; P < 0.01) along with the MELD score was independently associated with the overall survival in patients with HBV-ACLF. Patients with HBV-ACLF were stratified into two groups according to the serum NGAL level at baseline (low risk: <217.11 ng/mL and high risk: ≥ 217.11 ng/mL). The 90-day mortality rate was 22.73% (5/22) in the low-risk group and 71.88% (23/32) in the high-risk group. Moreover, NGAL, but not CysC, significantly improved the MELD score in predicting the prognosis of HBV-ACLF. CONCLUSION: The serum NGAL might be superior to CysC in predicting the prognosis of HBV-ACLF with the normal creatinine level.

Triglyceride-Glucose Index is an Independent Risk Factor for Hepatocellular Carcinoma Development in Patients with HBV-Related Liver Cirrhosis.

Aim: This study aimed to explore the effects of the triglyceride-glucose (TyG) index on hepatocellular carcinoma (HCC) development in patients with hepatitis B virus (HBV)-related liver cirrhosis (LC). Methods: A total of 242 patients with HBV-related LC were enrolled and followed-up. Logistic regression analysis was performed to investigate risk factors for HCC. Results: The median follow-up time was 37 months (range: 6-123 months). At the end of the follow-up, 11 (11.3%) patients with compensated cirrhosis (CC) and 45 (31.0%) with decompensated cirrhosis (DC) developed HCC. The TyG index was higher in the HCC group than in the non-HCC group (P=0.05). Univariate analysis showed that age (P<0.01), DC (P<0.01), TyG index (P=0.08), albumin (ALB) level (P=0.05), platelet (PLT) count (P<0.01), and HBV DNA positivity (P<0.01) were associated with HCC development. Multivariate analysis revealed that age, DC, TyG index, PLT count, and HBV DNA positivity were independent risk factors for HCC development (P=0.01, 0.01, <0.01, 0.05, and <0.01, respectively). For patients with DC, multivariate logistic regression analysis revealed that age, TyG index, and HBV DNA positivity were independent risk factors for HCC development (all P<0.05). A new model encompassing age, DC, TyG, PLT, and positive HBV DNA had optimal predictive accuracy in patients with DC or CC, with a cutoff value of 0.197. The areas under the receiver operating characteristic curves (AUROCs) of the model for predicting HCC development in patients with LC, DC, and CC were 0.778, 0.721, and 0.783, respectively. Conclusion: TyG index was identified as an independent risk factor for HCC development in patients with LC.

Investigation of temperature effects on wide steel box girder of suspension bridge based on long-term monitoring data.

The time-varying temperature distributions on bridge structures may remarkably change structural performance, which may result in differential strain/stress responses on structural members compared with the design conditions. Therefore, it is crucial to have a comprehensive understanding of temperature distributions and its effects on bridges. In this study, taking advantage of structural health monitoring technology, 1-year field monitoring data collected from a long-span suspension bridge were used to investigate the temperature distributions and their effects on the steel box girder. Specifically, the distributions and probability statistics of temperatures on the top and bottom plates were firstly analyzed. Based on which, the transverse and vertical temperature differences on the box girder were further examined, moreover, the representative values of temperature differences for various return periods were calculated by exceedance probability method. At end, a temperature prediction method was proposed to simulated the temperature field distributions during bridge life cycle, to provide substantial temperature data for estimating future operation condition. The results of this study were beneficial to structural evaluation of in-service bridges to ensure their serviceability and integrity in the life cycle.

Discovery of liver-targeted inhibitors of stearoyl-CoA desaturase (SCD1).

Inhibitors based on a benzo-fused spirocyclic oxazepine scaffold were discovered for stearoyl-coenzyme A (CoA) desaturase 1 (SCD1) and subsequently optimized to potent compounds with favorable pharmacokinetic profiles and in vivo efficacy in reducing the desaturation index in a mouse model. Initial optimization revealed potency preferences for the oxazepine core and benzylic positions, while substituents on the piperidine portions were more tolerant and allowed for tuning of potency and PK properties. After preparation and testing of a range of functional groups on the piperidine nitrogen, three classes of analogs were identified with single digit nanomolar potency: glycine amides, heterocycle-linked amides, and thiazoles. Responding to concerns about target localization and potential mechanism-based side effects, an initial effort was also made to improve liver concentration in an available rat PK model. An advanced compound 17m with a 5-carboxy-2-thiazole substructure appended to the spirocyclic piperidine scaffold was developed which satisfied the in vitro and in vivo requirements for more detailed studies.

A new model predicts hepatocellular carcinoma in patients with HBV-related decompensated liver cirrhosis and long-term antiviral therapy: a prospective study.

Background: We aimed to evaluate the prediction values of non-invasive models for hepatocellular carcinoma (HCC) development in patients with HBV-related liver cirrhosis (LC) and long-term NA treatment. Methods: Patients with compensated or decompensated cirrhosis (DC), who achieved long-term virological response, were enrolled. DC and its stages were defined by the complications including ascites, encephalopathy, variceal bleeding, or renal failure. Prediction accuracy of several risk scores, including ALBI, CAMD, PAGE-B, mPAGE-B and aMAP, was compared. Results: The median follow-up duration was 37 (28-66) months. Among the 229 patients, 9 (9.57%) patients in the compensated LC group and 39 (28.89%) patients in the DC group developed HCC. The incidence of HCC was higher in the DC group ( X 2 = 12.478, P < 0.01). The AUROC of ALBI, aMAP, CAMD, PAGE-B and mPAGE-B scores were 0.512, 0.667, 0.638, 0.663, 0.679, respectively. There was no significant difference in AUROC between CAMD, aMAP, PAGE-B and mPAGE-B (all P > 0.05). Univariable analysis showed that age, DC status and platelet were associated with HCC development, and multivariable analysis showed that age and DC status (both P < 0.01) were independent risk factors for HCC development, then Model (Age_DC) was developed and its AUROC was 0.718. Another model, Model (Age_DC_PLT_TBil) consisting of age, DC stage, PLT, TBil was also developed, and its AUROC was larger than that of Model (Age_DC) (0.760 vs. 0.718). Moreover, AUROC of Model (Age_DC_PLT_TBil) was larger than the other five models (all P < 0.05). With an optimal cut-off value of 0.236, Model (Age_DC_PLT_TBil) achieved 70.83% sensitivity, 76.24% specificity. Conclusion: There is a lack of non-invasive risk scores for HCC development in HBV-related DC, and a new model consisting of age, DC stage, PLT, TBil may be an alternative.

Presence of Serum Antinuclear Antibodies Does Not Impact Outcomes in HBV-Related Acute-on-Chronic Liver Failure.

BACKGROUND: The aim of this study was to provide new insights into the prevalence of positive antinuclear antibody (ANA) in patients with HBV-related acute-on-chronic liver failure (ACLF) and its impact on clinical outcomes. METHODS: A total of 116 patients with HBV-related ACLF treated at three clinical centers were retrospectively recruited. Serum concentrations of ANA were detected using the enzyme-linked immunosorbent assay kit. Multiple nuclear dots, rim-like, and centromere patterns of ANA were detected using indirect immunofluorescence assay on HEp-2 cells. RESULTS: Among the 116 patients with HBV-related ACLF, 17 (14.66%) were ANA positive. Most patients in both ANA positive and negative groups were males (88.2% and 83.8%). Patients with negative ANA had a higher international normalized ratio, model for end-stage liver disease (MELD), and MELD-sodium scores than those with positive ANA (all P < 0.05). Multiple nuclear dot pattern was detected in half of the patients (8/17, 47.06%), rim-like/membranous pattern was found in six patients, and centromere pattern was detected in the last three patients. For patients with ANA (+), IgM was lower, and it was positively correlated with IgG. For patients with ANA (-), C3 was positively correlated with C4, and both C3 and C4 were negatively correlated with INR and MELD (all P < 0.05). In addition, TBIL, INR, WBC, and PLT, but not ANA, resulted as independent risk factors associated with 90-day mortality. CONCLUSION: Positive ANA is frequent in HBV-related ACLF, and it does not seem to be associated with poor outcomes, but the pathogenesis of ACLF may be different between ANA (+) and ANA (-) groups.

The Age, Gamma-Glutamyl Transpeptidase and Platelet Index: A Novel Noninvasive Model for Predicting Hepatocellular Carcinoma in Patients with Hepatitis B Virus-Related Liver Cirrhosis.

Background and Aims: High incidence of hepatocellular carcinoma (HCC) exists in patients with liver cirrhosis (LC), but the predictive accuracy of noninvasive scoring systems (NSSs) is yet to be elucidated. The present study aimed to evaluate the predictive ability of fibrosis-4 (FIB-4), aminotransferase-to-platelet ratio index (APRI), and gamma-glutamyl transpeptidase to platelet ratio (GPR) in patients with LC, and to establish a new model with more accuracy. Methods: Data from 94 patients with compensated LC and 134 patients with decompensated cirrhosis (DC) were collected. The prediction accuracy of NSSs, including APRI, GPR, and FIB-4, was compared. Results: During a median follow-up of 37.5 months, 9 patients in the compensated LC group and 38 in the DC group developed HCC. For 228 patients, the area under the receiver operating characteristic curve (AUROC) of APRI, GPR, and FIB-4 was 0.596, 0.625, and 0.654, respectively. Multivariable logistic analysis showed that age, gamma-glutamyl transpeptidase (GGT), and platelet (PLT) were independent risk factors for HCC development, and a new model encompassing age, GGT, and PLT was superior to NSSs (all P<0.05). With an optimal cutoff value of 0.216, Model (Age_GGT_PLT) achieved 68.09% sensitivity and 69.61% specificity. Conclusion: NSSs, including APRI, GPR, and FIB-4, has a non-optimal accuracy in predicting HCC development in patients with HBV-related LC. Thus, the new model consisting of age, GGT, and PLT may be more accurate than NSSs.

Asialoglycoprotein receptor interacts with the preS1 domain of hepatitis B virus in vivo and in vitro.

BACKGROUND: The preS1 domain of the large envelope protein has been identified as an essential viral structure involved in hepatitis B virus (HBV) attachment. However, the cellular receptor(s) for HBV has not yet been identified. AIMS: To identify a cell-surface receptor for HBV, which could elucidate the molecular mechanism of HBV infection. METHODS: A novel yeast two-hybrid system was used to screen proteins interacting with the preS1 region of HBV. Their interaction was verified by yeast cotransformation, coimmunoprecipitation and mammalian two-hybrid assay, while their intracellular and tissue localization was analyzed by confocal microscopy and immunohistochemistry, respectively. RESULTS: Asialoglycoprotein receptor (ASGPR) interacted specifically and directly with the preS1 domain of HBV in vivo and in vitro. The levels of expression of preS1 and ASGPR in the liver were similar and correlated with each other. CONCLUSIONS: ASGPR is a candidate receptor for HBV that mediates further steps of HBV entry.

Hybrid Inspired Research on the Flying-Jumping Locomotion of Locusts Using Robot Counterpart.

Locusts are a kind of agile insects that can move and maneuver so efficiently in the unstructured terrain and complex environment. This marvel survivability of locusts benefits from their flying-jumping multi-modal locomotion. But until recently, the main influences of the locomotion performance are still a controversial and unknown issue. In this paper, the idea of hybrid inspired method that combines biologically inspired robot with robot inspired biology was proposed to explore the principle of flying-jumping locomotion of locusts. Firstly, we analyzed the influence of leg burrs and flapping wings on the jumping performance by the biological experiments. Nevertheless, individual heterogeneity and uncontrollability of locusts result in the unconvincing results of biological experiments. Therefore, according to the thought of robotics-inspired biology, we proposed and built a locust-inspired robot with flying-jumping locomotion via the principle of metamorphic mechanism based on the biological-inspired robot. Lastly, the preliminary robotic experiments were carried out to validate our thought that the flapping wings and leg burrs of locust have a great influence on the jumping performance. This robotics-inspired biology method remedied the shortcomings of biological experiments through the consistency and controllability of the robot experiments. Meanwhile, through the hybrid inspired research, the results show both the leg burrs and flapping wings can help the locust jump longer and improve the stability by adjusting the landing attitude to some extent, while the biological experiments dedicate that the locust with leg burrs and wings have the self-stability ability.

Efficacy and safety of tenofovir disoproxil fumarate in Chinese patients with chronic hepatitis B virus infection: A 2-year prospective study.

To date, a small number of studies concerning the effects and safety of tenofovir disoproxil fumarate (TDF) in Chinese individuals were conducted. In this study, we aimed to assess the antiviral effects and nephrotoxicity of TDF in Chinese patients with chronic hepatitis B virus (HBV) infection.Patients with chronic HBV infection were prospectively recruited and TDF treatment was given for 96 weeks. HBV serologic markers, HBV DNA, creatinine and phosphorus were collected.Fifty-seven treatment-naïve and 48 treatment-experienced patients were recruited. Irrespective of the prior treatment history, more than 95% of patients achieved virological response during 96 weeks treatment with TDF. Estimated glomerular filtration rate (eGFR) significantly declined in the first year of treatment in patients with chronic hepatitis B or younger age (<65 years old) (both P < .05), while that was not achieved in patients with liver cirrhosis or older age (≥65 years old) (both P > .05). For patients who were treatment-naïve or treated previously with adefovir dipivoxil, eGFR declined at the 48th week; however, eGFR was partially recovered at the 96th week. Furthermore, multivariable analysis showed that basal eGFR <90 mL/min/1.73 m (P = .001; odds ratio: 4.821; 95% confidence interval: 1.904-12.206) is the only independent risk factor for eGFR <90 mL/min/1.73 m at the 96th week.TDF has potent antiviral effect in both treatment-naïve and treatment-experienced patients.

Ezetimibe improves high fat and cholesterol diet-induced non-alcoholic fatty liver disease in mice.

Ezetimibe is a novel cholesterol and plant sterol absorption inhibitor that reduces plasma low-density lipoprotein-cholesterol by selectively binding to the intestinal cholesterol transporter, Niemann-Pick C1-Like 1. Mice deficient in Niemann-Pick C1-Like 1 are protected from high fat/cholesterol diet-induced fatty liver as well as hypercholesterolemia. The object of the present study was to determine whether ezetimibe treatment could reduce hepatic steatosis in diet-induced obese mice. C57BL/6J mice were fed a high fat/cholesterol containing semi-purified diet (45% Kcal fat and 0.12% cholesterol) for 7 months after weaning. These mice were not only obese, but also developed hepatomegaly and hepatic steatosis, with varying degrees of liver fibrosis and steatohepatitis. About 87% of the mice on the high fat/cholesterol diet for 7 months had elevated plasma alanine aminotransferase activity, a biomarker for non-alcoholic fatty liver disease. Chronic administration of ezetimibe for 4 weeks significantly reduced hepatomegaly by decreasing hepatic triglyceride, cholesteryl ester and free cholesterol in diet-induced obese mice fed high fat/cholesterol diet for 7 months. Chronic ezetimibe treatment also significantly decreased plasma alanine aminotransferase activity. These results suggest that ezetimibe may be a novel treatment for high fat/cholesterol-induced non-alcoholic fatty liver disease.

Incident hepatocellular carcinoma developing during tenofovir alafenamide treatment as a rescue therapy for multi-drug resistant hepatitis B virus infection: A case report and review of the literature.

Tenofovir disoproxil fumarate (TDF) is a potent nucleotide analogue with high barrier to resistance, which is recommended for multi-drug resistant hepatitis B virus (HBV) infection. However, nephrotoxicity has been reported during TDF treatment, and tenofovir alafenamide (TAF), which has comparable efficacy to TDF and improves bone and renal safety, can be used as a replacement strategy. Herein, we describe a clinical case concerning a 60-year-old individual suffering liver cirrhosis and renal dysfunction, and being infected with multidrug-resistant HBV. When failing treatment with TDF, he received TAF as a rescue therapy. TAF effectively inhibited HBV replication without worsening renal function or serum phosphorus abnormality. Furthermore, hepatocellular carcinoma (HCC) occurred during TAF treatment despite controlling the viral load. The risk of HCC could not be eliminated and should be monitored during TAF treatment.

Serum osteopontin is a predictor of prognosis for HBV-associated acute-on-chronic liver failure.

Acute-on-chronic liver failure (ACLF) is a syndrome with a high rate of short-term mortality, and clinically it is important to identify patients at high risk of mortality. The present study evaluated the value of osteopontin (OPN) in the prediction of 90-day mortality in patients with ACLF. A total of 54 patients with HBV-associated ACLF were enrolled, and serum OPN levels were determined in a prospective, observational study design. Survival analysis was performed using Kaplan-Meier curves, and multivariate Cox proportional hazards regression was used to analyze independent risk factors of mortality. Serum OPN was significantly higher in HBV-ACLF patients compared with patients with chronic hepatitis B and healthy controls (both P<0.01), and furthermore, was higher in those patients who succumbed to HBV-ACLF compared with surviving patients (P<0.05). OPN level positively correlated with total bilirubin (r=0.554, P<0.001), Model for End-Stage Liver Disease (MELD) score (r=0.234, P=0.038), MELD-Na score (r=0.379, P=0.005) and monocyte count (r=0.282, P=0.039), and OPN was an independent risk factor for 90-day mortality in ACLF (P=0.021, odds ratio=1.104, 95% confidence interval: 1.003-1.116). Furthermore, ACLF patients were stratified into three groups according to serum OPN levels (low mortality risk: <6,135 ng/ml; intermediate risk: 6,135-9,043 ng/ml; and high risk: >9,043 ng/ml), for which the 90-day mortality rates were 27.78 (5/18), 52.94 (9/17) and 73.68% (14/19), respectively, and those in the high risk had a poorer prognosis compared with the low risk group (P=0.009). In conclusion, serum OPN may be an independent risk factor associated with HBV-ACLF prognosis.

Gamma-glutamyl transpeptidase-to-platelet ratio predicts the prognosis in HBV-associated acute-on-chronic liver failure.

BACKGROUND: The gamma-glutamyl transpeptidase-to-platelet ratio (GPR) is a new noninvasive marker for assessing liver fibrosis. We aimed to evaluate the performance of GPR for prediction of 90-day mortality in patients with acute-on-chronic liver failure (ACLF). METHODS: A total of 355 patients with HBV-associated ACLF were enrolled from two clinical centers and divided into training group (n=210) and validation group (n=145). Potential risk factors for 90-day mortality were analyzed. RESULTS: Age, MELD score and GPR were independent risk factors associated with ACLF prognosis. A new scoring system (MELD-GPR) was developed. MELD-GPR=9.211-0.029×age-0.290×MELD-0.460×GPR. For ACLF patients with liver cirrhosis, the area under the receiver operating characteristic curve (AUROC) of MELD-GPR was 0.788, which was significantly higher than that of MELD and MELD-Na (0.706 and 0.666, respectively). Patients were stratified into three groups according to MELD-GPR scores (high risk: <-0.19, intermediate risk: -0.19-0.95, and low risk: >0.95), and the high-risk group (MELD-GPR<-0.19) had a poor prognosis (P<0.01). For ACLF patients without liver cirrhosis, MELD-GPR<0.95 predicted a poor prognosis. CONCLUSIONS: Incorporating GPR into MELD may provide more accurate survival prediction in patients with HBV-ACLF.

The missense mutation in Abcg5 gene in spontaneously hypertensive rats (SHR) segregates with phytosterolemia but not hypertension.

BACKGROUND: Sitosterolemia is a recessively inherited disorder in humans that is associated with premature atherosclerotic disease. Mutations in ABCG5 or ABCG8, comprising the sitosterolemia locus, STSL, are now known to cause this disease. Three in-bred strains of rats, WKY, SHR and SHRSP, are known to be sitosterolemic, hypertensive and they carry a missense 'mutation' in a conserved residue of Abcg5, Gly583Cys. Since these rat strains are also know to carry mutations at other genetic loci and the extent of phytosterolemia is only moderate, it is important to verify that the mutations in Abcg5 are causative for phytosterolemia and whether they contribute to hypertension. METHODS: To investigate whether the missense change in Abcg5 is responsible for the sitosterolemia we performed a segregation analysis in 103 F2 rats from a SHR x SD cross. Additionally, we measured tail-cuff blood pressure and measured intestinal lipid transport to identify possible mechanisms whereby this mutation causes sitosterolemia. RESULTS: Segregation analysis showed that the inheritance of the Gly583Cys mutation Abcg5 segregated with elevated plant sterols and this pattern was recessive, proving that this genetic change is responsible for the sitosterolemia in these rat strains. Tail-cuff monitoring of blood pressure in conscious animals showed no significant differences between wild-type, heterozygous and homozygous mutant F2 rats, suggesting that this alteration may not be a significant determinant of hypertension in these rats on a chow diet. CONCLUSION: This study shows that the previously identified Gly583Cys change in Abcg5 in three hypertension-susceptible rats is responsible for the sitosterolemia, but may not be a major determinant of blood pressure in these rats.

Rapid clearance of hexachlorobenzene from chylomicrons.

Toxic organochlorines that are present in food are lipophilic and carried by chylomicrons. We have studied the clearance of an organochlorine, hexachlorobenzene, from chylomicrons. Chylomicrons were obtained from mesenteric lymph of rats that were intraduodenally given 14C-hexachlorobenzene and 3H-triolein. The labeled chylomicrons were injected intravenously into recipient rats, and the clearance of isotopes was followed. Surprisingly, the hexachlorobenzene disappeared from the plasma more rapidly than the triolein. This unexpected result raises questions about the manner in which hexachlorobenzene is delivered to tissues. The tissue distribution of the hexachlorobenzene is consistent with its rapid uptake.

Discovery of a potent thiadiazole class of histamine h3 receptor antagonist for the treatment of diabetes.

A series of novel 2-piperidinopiperidine thiadiazoles were synthesized and evaluated as new leads of histamine H3 receptor antagonists. The 4-(5-([1,4'-bipiperidin]-1'-yl)-1,3,4-thiadiazol-2-yl)-2-(pyridin-2-yl)morpholine (5u) displayed excellent potency and ex vivo receptor occupancy. Compound 5u was also evaluated in vivo for antidiabetic efficacy in STZ diet-induced obesity type 2 diabetic mice for 2 or 12 days. Non-fasting glucose levels were significantly reduced as compared with vehicle-treated mice. In addition, 5u dose dependently blocked the increase of HbA1c after 12 days of treatment.

Antidiabetic properties of the histamine H3 receptor protean agonist proxyfan.

Proxyfan is a histamine H3 receptor protean agonist that can produce a spectrum of pharmacological effects including agonist, inverse agonist, and antagonist. We have discovered that proxyfan (10 mg/kg orally) significantly improved glucose excursion after an ip glucose tolerance test in either lean or high-fat/cholesterol diet-induced obese mice. It also reduced plasma glucose levels comparable to that of metformin (300 mg/kg orally) in a nongenetic type 2 diabetes mouse model. The dose-dependent decrease in glucose excursion correlated with inhibition of ex vivo H3 receptor binding in the cerebral cortex. In addition, glucose levels were significantly reduced compared with vehicle-treated mice after intracerebroventricular administration of proxyfan, suggesting the involvement of central H3 receptors. Proxyfan-induced reduction of glucose excursion was not observed in the H3 receptor knockout mice, suggesting that proxyfan mediates this effect through H3 receptors. Proxyfan reduced glucose excursion by significantly increasing plasma insulin levels in a glucose-independent manner. However, no difference in insulin sensitivity was observed in proxyfan-treated mice. The H1 receptor antagonist chlorpheniramine and the H2 receptor antagonist zolantidine had modest effects on glucose excursion, and neither inhibited the glucose excursion reduced by proxyfan. The H3 receptor antagonist/inverse agonist, thioperamide, had weaker effects on glucose excursion compared with proxyfan, whereas the H3 receptor agonist imetit did not affect glucose excursion. In conclusion, these findings demonstrate, for the first time, that manipulation of central histamine H3 receptor by proxyfan can significantly improve glucose excursion by increasing plasma insulin levels via a glucose-independent mechanism.