晚期糖化终末产物在去卵巢大鼠骨质疏松发病中的作用及氨基胍防治效果

目的　探讨晚期糖化终末产物 (AGEs)在去卵巢大鼠骨质疏松发病中的作用及氨基胍防治效果。方法　选用 1 0月龄大鼠通过卵巢切除诱导骨质疏松并用氨基胍防治其骨量丢失 ,测定其骨密度及骨胶原中 AGEs的含量及血、尿生化指标。结果　卵巢切除大鼠骨密度 (0 .2 0 7g/cm2 ± 0 .0 1 6 g/cm2 )明显低于假手术大鼠 (0 .2 36 g/cm2 ± 0 .0 1 0 g/cm2 ) (P<0 .0 1 ) ,而骨胶原 AGEs含量 (59.86 RU/mg胶原± 3.1 3 RU/mg胶原 )明显高于假手术组大鼠 (53.83RU/mg胶原± 5.46RU/mg胶原 ) (P<0 .0 1 )。卵巢切除大鼠血清雌激素 (4.50 pg/ml± 1 .73pg/ml)与假手术组(8.45 pg/ml± 2 .90 pg/ml)比较明显降低 (P<0 .0 2 ) ,2 4 h尿钙、尿钙与肌酐比值、尿磷、尿磷与肌酐比值均有升高趋势。卵巢切除大鼠给予氨基胍后骨密度 (0 .2 2 1 g/cm2± 0 .0 1 7g/cm2 )明显升高 (P<0 .0 5) ,骨胶原中 AGEs含量 (51 .2 3RU/mg胶原± 7.46RU/mg胶原 )明显降低 (P<0 .0 1 ) ,血清雌激素 (8.59pg/ml± 3.0 1 pg/ml)明显升高 (P<0 .0 1 ) ,2 4 h尿钙、尿钙与肌酐比值降低 ,2 4 h尿羟脯氨酸升高 ,与手术组比较有显著差异 (P<0 .0 5)。结论　卵巢切除后 ,雌激素的降低和 AGEs的增加是导致骨质疏松的主要原因。而氨基胍通过降低体内 AGE     

老年人腰椎和髋部骨密度测定T评分的一致性比较

目的 探讨老年人腰椎和髋部双能X线骨密度(DEXA)测定T评分的一致性及髋部骨密度(BMD)T评分在骨质疏松诊断中的意义。方法 在排除患有影响骨量的疾病及使用影响骨代谢药物者后，选择60-89岁老年人260(其中男123人，女137人)例作为为研究对象。受检者均接受问卷调查、胸腰段脊椎正侧位X线摄片，DEXA测定2-4腰椎(L2-4)椎体前后位和左髋部BMD(若左髋部发生过骨折或存有明显病变则改测右髋部)，并进行有关统计分析。结果 老年男性各年龄组L2-4 BMD T评分比髋部要高(P＜0．01或P＜0.05)；老年女性除在65—69岁、85—89岁年龄组腰椎BMD T评分比髋部要高(P＜0．01和P＜0.05)外，其余各组则差异无显著性。按照WHO标准，以髋部、腰椎和同时以髋部、腰椎BMD T评分为依据，在123例男性中，分别有19、6、5人被诊断为骨质疏松症；在137例女性中，则分别有35、17、14人被诊断为骨质疏松症；单以腰椎和同时以髋部、腰椎BMD T评分为依据所检出的骨质疏松症患者人数均少于单以髋部BMD T评分为依据者(P＜0．01)。结论 在老年人尤其是老年男性，其腰椎BMD T评分明显高于髋部，腰部BMD T评分在骨质疏松诊断中的意义更为重要。     

Association of diet quality,physical activity,and abdominal obesity with metabolic syndrome z-score in black and white adolescents in the US

Background and aimsMetabolic syndrome (MetS) affects ～10% of adolescents and is associated with cardiometabolic disease risk. The most prevalent MetS component is abdominal obesity. Healthy diet and physical activity (PA) are inversely associated with abdominal obesity and may reduce MetS risk in youth. Our aim was to examine associations of diet, activity, and abdominal obesity with MetS z-score (MetS-z).Methods and resultsAn analysis of National Health and Nutrition Examination Survey (NHANES) 2011–2016 data in adolescents was performed. Healthy Eating Index (HEI)- 2015 scores were calculated for diet quality, PA habits were used to determine alignment with national guidelines, and abdominal obesity was assessed by sagittal abdominal diameter (SAD). MetS-z represented severity or potential risk for MetS. Multivariable regression evaluated the relationships of HEI, SAD and PA with MetS-z. Among 1214 black and white adolescents, SAD was significantly associated with MetS-z [β (95% CI) = 0.17 (0.16, 0.19); P <0.0001] while HEI-2015 components showed associations with MetS-z overall (HEI total, dairy, and sodium scores), and by sex (total, refined grains, dairy for males; added sugar, protein, whole grains for females). Mean HEI-2015 score was 47.4/100 (51.6 using the population-ratio method), and the proportion of adolescents meeting national PA guidelines was 37.6%, yet PA was not a significant predictor of MetS-z.ConclusionsUS adolescents have poor diet quality and fewer than half meet PA guidelines. Strategies for preventing MetS and related conditions in adolescence should focus on weight management – specifically, abdominal fat reduction – with individualized diet counseling.     

Maintenance of integrity and function of isolated hepatocytes during extended suspension culture at 25°C

Abstract: Isolated hepatocytes in suspension provide a number of advantages for use in bioartificial liver device, however, poor stability of this cell preparation at physiological temperatures is an apparent barrier preventing their use. We therefore investigated the integrity and differentiated function of isolated rat hepatocytes under conditions of mild hypothermia. Isolated hepatocytes were suspended in a bicarbonate buffered saline medium, supplemented with glucose and bovine serum albumin (BSA), and maintained for 48 h at 25 °C on a rotary shaker under an atmosphere of 95% O₂ and 5% CO₂. Under these conditions there was no significant decline in cell viability and good preservation of cellular morphology on transmission electron microscopy for at least 24 h. Isolated hepatocytes in suspension at 25 °C were also able to maintain normal Na ⁺ and K ⁺ ion gradients. The cellular energy status ([ATP], ATP/ADP ratio, cytoplasmic and mitochondrial redox potentials), metabolic function (urea synthesis and ammonia removal), albumin synthesis and phase I and phase II drug detoxification activity of these cells were also maintained for at least 24 h post isolation. These observations demonstrate the robust nature of mildly hypothermic isolated hepatocytes in suspension and encourage further studies re‐examining the feasibility of using this cell preparation in bioartificial livers.     

南宁铁路辖区职工华支睾吸虫感染及相关因素的调查

目的 了解南宁铁路辖区职工华支睾吸虫感染情况及影响因素。方法 用改良加藤厚涂片法粪检，计数虫卵；以问卷方式收集受检者性别、年龄、职业、籍贯、常年居住地、经济水平、文化程度、吃鱼方式及菜刀、砧板使用习惯等相关因素；应用单因素及多因素Logistic回归分析方法研究华支睾吸虫感染的各种影响因素。结果 共调查836人，华支睾吸虫感染率为47．01％，其中男性为50．78％，女性为4．41％；南宁以北、南宁城区、南宁以南片区感染率分别为67．61％、43．94％、35．29％（P〈0．01）；有生食鱼虾史者感染率高达67．33％。多因素回归分析结果表明，对华支睾吸虫感染有影响的因素主要有吃鱼习惯、居住片区、性别。结论 南宁铁路辖区职工华支睾吸虫感染形势严峻，吃鱼习惯是影响感染率的首要因素，应通过加强卫生宣教提高职工的防病意识，同时开展普查普治，才能最大限度控制华支睾吸虫病在该地区的流行。     

青蒿素衍生物体外抗卡氏肺孢子虫作用的扫描电镜观察

目的 观察体外培养的卡氏肺孢子虫(Pc)经双氢青蒿素、青蒿琥酯作用后不同时相虫体表面结构变化。方法 将Pc接种入含HepG-2细胞的培养皿内并分别加入双氢青蒿素50μmol/L、青蒿琥酯100μmol/L、喷他脒15μmol/L、0.3％乙醇与空白对照。双氢青蒿素组于用药后1、2、4、8、12、16h作扫描电镜观察,后4组于用药后12h取样作扫描电镜观察。结果 双氢青蒿素作用2h后,Pc表面开始出现损伤,最初为表面绒毛脱落,残存绒毛肿胀呈球状,虫体体积增大。随着时间延长,虫体表面损伤明显,8h后表膜出现大小不等孔洞。青蒿琥酯组改变相同,但较轻微。结论 青蒿素衍生物可引起Pc虫体表膜损伤,通透性增加,功能障碍。     

卫氏并殖吸虫后尾蚴的透射电镜观察

应用透射电镜首次观察了卫氏并殖吸虫后尾蚴的超微结构。虫体由体被、实质组织、肠腔及排泄囊所构成。体被由皮层、肌层、皮层细胞组成。皮层为一合体层,包括外质膜、皮层细胞质和基质膜。皮层表面见许多指状突起,突起有多级分枝。皮层基质内有皮棘,其根部位于基质膜,顶端突出于皮层表面但被外质膜覆盖,横切面上可见网格样结晶,基质内遍布球形、杆状两型分泌小体。皮层细胞位于肌层深部,细胞核位于其内,浆内可见两型特征性分泌小体,皮层细胞发生多条胞质小管穿过肌层及基底膜与皮层相连。结果提示皮层是后尾蚴吸收营养物质的主要部位。     

Pre-Menopausal Breast Fat Density Might Predict MACE During 10 Years of Follow-Up: The BRECARD Study

ObjectivesThis study sought to determine whether the breast gland adipose tissue is associated with different rates of major adverse cardiac events (MACEs) in pre-menopausal women.BackgroundTo our knowledge, no study investigated the impact of breast adipose tissue infiltration on MACEs in pre-menopausal women.MethodsProspective multicenter cohort study conducted on pre-menopausal women >40 years of age without cardiovascular disease and breast cancer at enrollment. The study started in January 2000 and ended in January 2009, and the end of the follow-up for the evaluation of MACEs was in January 2019. Participants underwent mammography to evaluate breast density and were divided into 4 groups according to their breast density. The primary endpoint was the probability of a MACE at 10 years of follow-up in patients staged for different breast deposition/adipose tissue deposition.ResultsThe propensity score matching divided the baseline population of 16,763 pre-menopausal women, leaving 3,272 women according to the category of breast density from A to D. These women were assigned to 4 groups of the study according to baseline breast density. At 10 years of follow-up, we had 160 MACEs in group 1, 62 MACEs in group 2, 27 MACEs in group 3, and 16 MACEs in group 4. MACEs were predicted by the initial diagnosis of lowest breast density (hazard ratio: 3.483; 95% confidence interval: 1.476 to 8.257). Further randomized clinical trials are needed to translate the results of the present study into clinical practice. The loss of ex vivo breast density models to study the cellular/molecular pathways implied in MACE is another study limitation.ConclusionsAmong pre-menopausal women, a higher evidence of adipose tissue at the level of breast gland (lowest breast density, category A) versus higher breast density shows higher rates of MACEs. Therefore, the screening mammography could be proposed in overweight women to stage breast density and to predict MACEs. (Breast Density in Pre-menopausal Women Is Predictive of Cardiovascular Outcomes at 10 Years of Follow-Up [BRECARD]; NCT03779217)     

Microvascular function at the margins of early experimental myocardial infarcts in isolated rabbit hearts

Summary Injection of low-viscosity resin was used to identify in situ functional blood vessels at the margins of developing regional myocardial infarcts. The ventral interventricular branch (VIB) of the left coronary artery was occluded for 0–240 min in 20 isolated perfused rabbit hearts. After perfusion fixation with glutaraldehyde, resin was injected into the coronary arteries—that injected into the VIB contained dispersed lead dioxide and that injected into the remainder of the heart contained Fat Red 7B dye. This allowed macroscopic and microscopic identification of functional blood vessels. Following transmural freeze fracture, left ventricles were examined using back-scattered electron imaging in a scanning electron microscope. Close to 60% of capillaries in nonischemic myocardium allowed the passage of resin. Thirty minutes of ischemia produced a hyperemic increase to 80%–90% in the proportion of filled vessels. After 60 min, however, a severe reperfusion defect corresponding to the no-reflow phenomenon had developed, with virtually all vessels collapsed and <10% functional. Among the structurally normal myocytes adjacent to the infarct margin there was a significant reduction (to 30%–40%) in the proportion of functional capillaries. This was due to groups of dilated vessels which were not accessible to arterial supply. Although these marginal low-flow regions were of small volume at any one point in time, they seem likely to contribute to the progression of ischemic necrosis, and are probably nonfunctional due to the compression of their venous drainage traversing the infarct.This research was supported by grants from the Medical Research Council of New Zealand and the National Heart Foundation of New Zealand.