Enhanced high‐mobility group box 1 (HMGB1) modulates regulatory T cells (Treg)/T helper 17 (Th17) balance via toll‐like receptor (TLR)‐4‐interleukin (IL)‐6 pathway in patients with chronic hepatitis B

High‐mobility group box 1 (HMGB1) proteins are substantially up‐regulated in acute and chronic hepatitis. However, the immunopathogenic role of HMGB1 in patients with chronic hepatitis B (CHB) has not been elucidated. In this study, using a cohort of 36 CHB patients, we demonstrated a crucial role for HMGB1 to modulate balance between regulatory T (Treg) and T helper 17 (Th17) cells via the toll‐like receptor (TLR)‐4‐interleukin (IL)‐6 pathway. Serum HMGB1 levels were dramatically higher in CHB patients and increased along with liver injury, inflammation and fibrosis. Notably, HMGB1 increased along with decreased Treg/Th17 cells ratios in the periphery or intrahepatic microenvironment, which provides a clue for HMGB1 to favour Th17 responses whereas inhibit Treg responses. For in vitro studies, serum pools were constructed with serum from CHB patients at an advanced stage, whereas peripheral blood mononuclear cells (PBMC) pools were constructed with cells from those at an early stage. CHB‐serum significantly enhanced retinoic acid‐related orphan receptor‐γt (RORγt), whereas they inhibited forkhead box P3 (Foxp3) expression in CHB‐PBMC, which could be reversed by blocking of HMGB1, TLR4, or IL‐6. Besides, recombinant HMGB1 (rHMGB1) dose‐dependently up‐regulated RORγt whereas down‐regulated Foxp3 expression in CHB‐PBMC, and meanwhile, rHMGB1 enhanced TLR4 and IL‐6 expression in CHB‐PBMC. Moreover, the axis of HMGB1–TLR4‐IL‐6–Treg/Th17 required noncontact interactions between CD4 and non‐CD4 cells. In addition, rHMGB1 down‐regulated anti‐inflammatory proteins on CD4⁺CD25⁺ cells whereas up‐regulated pro‐inflammatory cytokines in CD4⁺CD25⁻ cells. In summary, enriched HMGB1 in CHB patients shifts Treg/Th17 balance to Th17 dominance via the TLR4‐IL‐6 pathway, which exacerbates liver injury and inflammation.     

Calcium Channel Blocker Compared With Angiotensin Receptor Blocker for Patients With Hypertension: A Meta‐Analysis of Randomized Controlled Trials

To explore the clinical effects of a calcium channel blocker compared with an angiotensin II receptor blocker in hypertensive patients, the authors collected data from randomized controlled trials. The pooled outcomes were all‐cause mortality, stroke, myocardial infarction, and heart failure. Eight head‐to‐head trials enrolling 25,084 patients were included. There was no significant mortality difference in the two arms (relative risk, 0.99; 95% confidence interval, 0.91–1.07). However, calcium channel blockers were more effective in reducing stroke (relative risk, 0.87; 95% confidence interval, 0.76–0.99) and myocardial infarction incidence (relative risk, 0.86; 95% confidence interval, 0.76–0.98). There was no significant difference with heart failure incidence between the two arms but a lower trend in patients with angiotensin II receptor blockers was noted (relative risk, 1.4; 95% confidence interval, 0.99–1.98). The meta‐analysis suggested that initially use of a calcium channel blocker might be superior to an angiotensin II receptor blocker for prevention of stroke and myocardial infarction.     

Engineering of an epoxide hydrolase for efficient bioresolution of bulky pharmaco substrates

Optically pure epoxides are essential chiral precursors for the production of (S)-propranolol, (S)-alprenolol, and other β-adrenergic receptor blocking drugs. Although the enzymatic production of these bulky epoxides has proven difficult, here we report a method to effectively improve the activity of BmEH, an epoxide hydrolase from Bacillus megaterium ECU1001 toward α-naphthyl glycidyl ether, the precursor of (S)-propranolol, by eliminating the steric hindrance near the potential product-release site. Using X-ray crystallography, mass spectrum, and molecular dynamics calculations, we have identified an active tunnel for substrate access and product release of this enzyme. The crystal structures revealed that there is an independent product-release site in BmEH that was not included in other reported epoxide hydrolase structures. By alanine scanning, two mutants, F128A and M145A, targeted to expand the potential product-release site displayed 42 and 25 times higher activities toward α-naphthyl glycidyl ether than the wild-type enzyme, respectively. These results show great promise for structure-based rational design in improving the catalytic efficiency of industrial enzymes for bulky substrates.Optically pure epoxides and the corresponding vicinal diols are valuable chiral building blocks for the production of pharmaceutically active compounds and other fine chemicals (1). Existing approaches for preparing enantiopure epoxides and diols include the asymmetric epoxidation or dihydroxylation of olefin substrates and the resolution of racemic epoxides. These reactions can be accomplished with either chemical catalysts such as chiral salen cobalt complexes and porphyrin manganese adducts or biocatalysts such as monooxygenases and epoxide hydrolases (EHs) (2–4). In the past two decades, EHs have received much attention because they are cofactor-independent enzymes that are “easy to use” for catalyzing the hydrolysis of racemic epoxides to yield highly enantiopure epoxides and vicinal diols (1, 5, 6). However, application of EHs in laboratory and industry was often hindered by their narrow substrate scope, low enantioselectivity, and regioselectivity, or product inhibition (7, 8).Many protein-engineering efforts have been made to overcome these drawbacks (9, 10). For example, directed evolution by error-prone PCR or DNA shuffling has been used to enhance the activity and enantioselectivity of EHs (11–13). Structure-guided mutagenesis also generated a few EH variants with improved catalytic performance (14–16). The strategy of iterative Combinatorial Active Site-Saturation Test (CAST) combines the rational approach and directed evolution to yield high-quality and small focused mutant libraries for screening EHs with better enantioselectivity (7, 17). By mutating residues at the substrate-binding site, the substrates of EHs have been expanded to include cyclic meso-epoxides, phenyl glycidyl ether (PGE) derivatives, and other styrene oxide-like analogs (18, 19). However, the catalytic efficiency of EH is still not satisfactory for bulky epoxide substrates including precursors of (S)-propranolol, (S)-alprenolol, and other β-adrenergic receptor blocking drugs (20, 21).In this work, we select BmEH, an EH cloned from Bacillus megaterium ECU1001, to expand its substrate scope for bulky pharmaco substrate α-naphthyl glycidyl ether (NGE). This enzyme is a potential industrial biocatalyst because it has unusual (R)-enantioselectivity and resolves ortho-substituted PGEs and para-nitrostyrene oxide with excellent enantiomeric ratios (E > 200) (22). We first identified the active tunnel of BmEH by solving its crystal structure complexed with a substrate analog phenoxyacetamide (POA) and analyzing the routes of substrate entry and product release by mass spectrum analysis. Alanine scanning experiments targeted to the potential product-release site of BmEH resulted in two variants, F128A and M145A, with efficient bioresolution abilities on NGE. Further kinetic measurements and structural analysis showed that M145A has much higher activity for the transition state intermediate formation, whereas both mutants exhibited expanded product-release site. The M145A BmEH variant has been successfully applied for the preparation of (S)-propranolol on a gram scale. The engineering of the potential product-release site described herein should have great promise for structure-based rational design of better industrial enzymes.     

Mechanistic roles for calcium and vitamin D in the regulation of body weight

Low intakes of calcium and inadequate vitamin D status often cluster with higher prevalence rates of obesity. Consequently, there has been much interest in the mechanisms by which calcium and vitamin D could regulate body weight and adiposity. This review has focused on randomized controlled trials (RCTs) that have manipulated these nutrients and studied pathways of energy balance. Overall, there is consistent evidence that calcium and vitamin D increase whole body fat oxidation after single and multiple meals, and that calcium promotes a modest energy loss through increased faecal fat excretion. The evidence is equivocal for a greater diet‐induced thermogenesis, increased lipolysis, suppression of key lipogenic enzymes, decreased hunger ratings or reduced energy/macronutrient intake. Emerging evidence suggests a potential improvement in insulin sensitivity following vitamin D that would impinge on food intake and substrate oxidation. However, the very few RCTs on supplemental vitamin D and energy balance have not explored postprandial avenues of the hormone's actions. Future efforts in this area need to define the threshold intake of these nutrients that would maximize metabolic and gastrointestinal outcomes. Such studies would provide a platform for endorsing the non‐skeletal role of calcium and vitamin D in human pathophysiology.     

高度近视合并脉络膜脱离型视网膜脱离预后相关因素分析

目的 分析高度近视合并脉络膜脱离型孔源性视网膜脱离（RRD-CD） 患者的预后相关因素。设计 回顾性病例系列。研究对象 2004-2018年北京同仁医院高度近视合并RRD-CD患者占836例。方法 回顾北京同仁医院住院HIS系统,收集高度近视合并RRD-CD手术治疗患者临床资料。随访6个月视网膜复位为复位组,发生视网膜再脱离为未复位组。采用Logistic回归法分析视网膜脱离复发的危险因素。主要指标 手术成功率及复发危险因素。结果 共纳入高度近视合并RRD-CD患者836例,平均年龄（56.51±12.14）岁;男性518例（61.9%）,右眼发病434例 （51.9%）。视网膜脱离未复位为22.7%,与视网膜复位患者相比,未复位患者年龄较轻,术前视力、眼轴、晶状体状态、视网膜裂孔、增生性玻璃体视网膜病变（PVR）等级及手术方式等差异均有统计学意义,其中年龄〔优势比（OR）=0.972,95%可信区间（95%CI）,0.967~0.989〕,术前视力光感（OR=1.898,95%CI为1.297~2.777）,人工晶状体眼（OR=1.860,95%CI为1.255~2.758）,眼轴>30 mm（OR=1.718,95%CI为1.240~2.379）,巨大视网膜裂孔（OR=2.464,95%CI为1.495~4.063）及PVR D级（OR=1.551,95%CI为1.046~2.300）为视网膜脱离未复位的危险因素。结论 高度近视合并RRD-CD患者男性比例大,中年发病、超高度近视、人工晶状体眼、巨大视网膜裂孔及PVD D级患者首次手术成功率低,视网膜脱离易复发。（眼科,2021,30： 42-46）     

Peripheral arterial filling time and peripheral retina fluorescence features in ultra-widefield angiography

AIM: To evaluate the peripheral arterial filling time (PAFT) and venous filling time (VFT) in eyes without known diseases that may influence filling process using ultra-widefield (UWF) fluorescein angiography (FA), and to review the peripheral retina fluorescence features. METHODS: A total of 30 eyes of 30 patients were retrospectively reviewed in this observational study. UWF-FA was performed using Optos 200Tx. PAFT and VFT was recorded. The interval between the arterial or venous filling completion and the previous photo was documented. The appearance of the far peripheral retina was described as either granular background fluorescence or mottled fluorescent band or vascular leakage. Terminal vascular patterns was described as loop pattern or branching pattern. Microvascular abnormalities such as arteriovenous shunting, vessels crossing the horizontal raphe, right angle vessels, terminal networks, capillary nonperfusion, drusen or microaneurysms were evaluated. RESULTS: The normal limits of PAFT was 3.397-8.984s and 4.399-11.753s for VFT. The appearance of the far peripheral retina, defined as granular background (63%), mottled fluorescence (20%), or vascular leakage (17%), was symmetrical between both eyes. Capillary nonperfusion (23%) and microaneurysms (40%) were more frequently found in eyes with loop pattern than in eyes with branching pattern. Other peripheral signs such as right angle vessels (73%), and terminal networks (80%) were commonly seen on UWF-FA in the normal peripheral retina. CONCLUSION: The main courses of retinal artery and vein filling time are overlapping with each other on UWF-FA. Notably, the arterial filling process is completed in the arteriovenous phase rather than the traditionally named arterial phase. There are various manifestations in the peripheral retina of normal eyes.     

Molecular simulations of gas transport in hydrogenated nitrile butadiene rubber and ethylene–propylene–diene rubber

Diffusion and sorption of five gases (H₂, N₂, O₂, CO₂, CH₄) in hydrogenated nitrile butadiene rubber (HNBR) and ethylene–propylene–diene rubber (EPDM) have been investigated by molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) simulations. The diffusion coefficients of gas molecules in HNBR and EPDM are well correlated with the effective penetrant diameter except for CO₂. CO₂ shows a lower diffusion coefficient due to its linear shape. Additionally, the favorable interaction between CO₂ and HNBR is another factor for its lower diffusion coefficient in HNBR. HNBR shows lower diffusion coefficients than EPDM. This is because the polar –CN groups in HNBR chains increase interchain cohesion and result in tight intermolecular packing, low free volume and poor chain mobility, which decreases the diffusion coefficients of HNBR. The solubility coefficients of CH₄, O₂, N₂ and H₂ in HNBR are lower than those in EPDM, which is a result of the weak HNBR–penetrant interactions and low free volume of HNBR. However, the solubility coefficient of CO₂ in HNBR is higher than in EPDM. This is attributed to the strong interaction between CO₂ and HNBR. H₂, O₂, N₂ and CH₄ show lower permeability coefficients in HNBR than in EPDM, while CO₂ has higher permeability coefficients in HNBR. These molecular details provide critical information for the understanding of structures and gas transport between HNBR and EPDM.

Diffusion and sorption of five gases (H₂, N₂, O₂, CO₂, CH₄) in HNBR and EPDM were explored by MD and GCMC simulations.     

Outcome of laparoscopic colectomy for cancer in elderly patients

Background

Resection for colon cancer in the elderly is a major undertaking. However, data on the outcome and survival of elderly patients who underwent laparoscopic resection for colon cancer are limited. This study of patients older than 75 years compared outcome and survival between those who underwent laparoscopic resection and those who had open resection for colorectal cancer.

Methods

From 2000 to 2009, 434 patients ages 75 years and older who underwent elective resection for colon cancer were included in the study. Patients who had rectal cancer or had undergone emergency operations were excluded. Preoperative diagnosis was determined by colonoscopy, and computed tomography scan was performed for preoperative staging. Data on the patients’ demographics, operative details, pathology results, postoperative results, and survival were collected prospectively. The patients who underwent laparoscopic surgery were compared with those who had open surgery.

Results

The study included 434 patients (210 men) with a median age of 80 years (range 75–95 years). Of these 434 patients, 189 underwent laparoscopic resection. Nine patients (4.8 %) required conversion to open operation. The patients did not differ in terms of age, gender, incidence of medical comorbidities, or stage of disease. The median operating time was longer in the laparoscopic group, but the blood loss was significantly less. Laparoscopic resection was associated with a lower mortality rate and a shorter hospital stay (p < 0.05). The open resection group had significantly more cardiac complications (p < 0.05). The overall 5-year survival rates were similar between the patients who had laparoscopic resections and those who had open surgery.

Conclusions

For patients older than 75 years, laparoscopic resection of colon is associated with less intraoperative blood loss, a shorter hospital stay, fewer cardiac complication, and a lower mortality rate than open resection. Therefore, the authors recommend laparoscopic resection of colon cancer as the treatment of choice for elderly patients.     

Association Between Lipid Profiles and Left Ventricular Hypertrophy: New Evidence from a Retrospective Study

ObjectiveTo explore the association between lipid profiles and left ventricular hypertrophy in a Chinese general population.MethodsWe conducted a retrospective observational study to investigate the relationship between lipid markers [including triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL-cholesterol, apolipoprotein A-I, apolipoprotein B, lipoprotein[a], and composite lipid profiles] and left ventricular hypertrophy. A total of 309,400 participants of two populations (one from Beijing and another from nationwide) who underwent physical examinations at different health management centers between 2009 and 2018 in China were included in the cross-sectional study. 7,475 participants who had multiple physical examinations and initially did not have left ventricular hypertrophy constituted a longitudinal cohort to analyze the association between lipid markers and the new-onset of left ventricular hypertrophy. Left ventricular hypertrophy was measured by echocardiography and defined as an end-diastolic thickness of the interventricular septum or left ventricle posterior wall > 11 mm. The Logistic regression model was used in the cross-sectional study. Cox model and Cox model with restricted cubic splines were used in the longitudinal cohort.ResultsIn the cross-sectional study, for participants in the highest tertile of each lipid marker compared to the respective lowest, triglycerides [odds ratio (OR): 1.250, 95%CI: 1.060 to 1.474], HDL-cholesterol (OR: 0.780, 95%CI: 0.662 to 0.918), and lipoprotein(a) (OR: 1.311, 95%CI: 1.115 to 1.541) had an association with left ventricular hypertrophy. In the longitudinal cohort, for participants in the highest tertile of each lipid marker at the baseline compared to the respective lowest, triglycerides [hazard ratio (HR): 3.277, 95%CI: 1.720 to 6.244], HDL-cholesterol (HR: 0.516, 95%CI: 0.283 to 0.940), non-HDL-cholesterol (HR: 2.309, 95%CI: 1.296 to 4.112), apolipoprotein B (HR: 2.244, 95%CI: 1.251 to 4.032) showed an association with new-onset left ventricular hypertrophy. In the Cox model with forward stepwise selection, triglycerides were the only lipid markers entered into the final model.ConclusionLipids levels, especially triglycerides, are associated with left ventricular hypertrophy. Controlling triglycerides level potentiate to be a strategy in harnessing cardiac remodeling but deserve to be further investigated.     

四磨汤口服液对脾虚便秘小鼠肠黏膜结构的影响

目的探讨四磨汤口服液对脾虚便秘小鼠肠黏膜结构损伤的修复作用。方法通过灌胃番泻叶水煎液7 d,控制饮食、饥饱失常8 d建立小鼠脾虚便秘模型,造模成功后,治疗组给予四磨汤口服液灌胃,治疗5 d,模型组和正常组给予等量无菌水灌胃,取肠道组织进行病理切片观察。结果四磨汤能修复损伤的空肠、回肠黏膜结构,减轻炎症细胞浸润,且能增加盲肠的杯状细胞数目。结论四磨汤口服液治疗脾虚便秘,其作用可能与修复小鼠肠黏膜结构相关。