板栗总苞中的抗糖尿病活性成分

目的分离鉴定板栗(Castanea mollissima Blume)总苞中抗糖尿病活性化合物。方法采用正-反相硅胶柱色谱和制备型HPLC进行分离,经理化常数测定、核磁共振技术分析等方法鉴定化合物的结构;对分离得到的单体化合物进行醛糖还原酶(aldose reductase,AR)抑制活性实验。结果从活性部位中分离得到9个化合物,分别为山柰酚(kaempferol,1)、没食子酸(gallic acid,2)、3,4-二羟基苯甲酸(3,4-dihydroxy-benzoic acid,3)、鞣花酸(ellagic acid,4)、苯甲基-6-O-β-D-吡喃葡萄糖苷(benzyl-O-β-D-glucopyranoside,5)、没食子酸正丁酯(n-butyl gallate,6)、2,4,6-三羟基苯甲酸(2,4,6-trihydroxy-benzoic acid,7)、没食子酸甲酯(methyl-gallate,8)、豆甾烷-4-烯-3,6-二酮(stig-mast-4-en-3,6-dione,9)。结论化合物5-7为首次从该属植物中分离得到,活性结果显示9个化合物均显示不同程度抑制活性,其中化合物4、5最为显著。     

A Solid-Phase Assay for the Detection of Anti-Sperm Antibodies

PROBLEM: ELISA is an ideal assay method for a large-scale screening of anti-sperm antibodies among a large number of infertile males. However, conventional ELISA with whole spermatozoa needs time-consuming steps of centrifugation. METHOD: A solid-phase assay used for detecting anti-sperm antibodies was established. This assay is suitable not only for detecting circulating anti-sperm antibodies of IgG, IgM, and IgA subclass simultaneously but also for screening hybridomas secreting anti-sperm monoclonal antibodies (mAbs). The microtiter plates, on which solubilized sperm antigens are fixed, can be stored at ? 80°C for up to six months without losing reactivity with anti-sperm antibodies. RESULTS: Using this assay, 53 sera (13 were proven positive and 40 were proven negative for sperm agglutination antibody) were tested. Although the false-negative rate was 0%, the false-positive rate was 32%. One thousand one hundred sixty-five supernatants from hybridomas constructed with splenocytes of mice who were hyperimmunized with human sperm and nonsecreting myeloma cells were tested by this solid-phase assay and two anti-sperm mAb secreting clones were selected and established. CONCLUSIONS: It is recommended that for research work this assay could be used for the first screening of the hybridoma secreting anti-sperm mAb, and for clinical use this assay might be suitable for the first screening of sera of infertile patients. However, conventional bioassays should follow to confirm the biological meaning of the positivity.     

A synthetic peptide derived from staphylokinase enhances plasminogen activation by tissue‐type plasminogen activator

Summary. Background: A synthetic nonadecapeptide (SP; GPYLMVNVTGVDGKGNELL) previously enhanced the activation of plasminogen by the SAK/plasmin complex. Objectives: To identify the binding site for SP on plasminogen and elucidate the effects of SP on plasminogen activation by the tissue‐type plasminogen activator (t‐PA). Methods: The effects of SP on plasminogen activation were estimated using a chromogenic substrate and from the cleavage of plasmin on SDS‐PAGE under reduced conditions. The binding to SP of various peptides derived from the amino acid sequence of plasminogen was analyzed with an IAsys biosensor. The SP‐mediated structural change to plasminogen was analyzed by circular dichroism (CD) spectroscopy. The thrombolytic effects of SP were examined using a mouse model of thrombosis. Results: SP enhanced the activation of plasminogen by t‐PA. The catalytic efficiency (k_cat/K_m) of Glu‐plasminogen activation by t‐PA was 11.4‐fold higher in the presence than absence of SP. The binding of SP to plasminogen was greatly inhibited by a synthetic peptide, FEKDKYILQGVTSWGLG, located close to the C‐terminal of the plasminogen B region. Near‐ultraviolet CD spectra of the complex between SP and Glu‐plasminogen significantly differed from those of Glu‐plasminogen. When SP was administered in a mouse model of thrombosis, early recanalization was observed in a dose‐dependent manner. However, SP did not cause recanalization in t‐PA gene‐deficient mice. Conclusions: SP bound to the B region and promoted the activation of plasminogen by t‐PA, and then induced effective thrombolysis.     

Histochemical localisation of versican, aggrecan and hyaluronan in the developing condylar cartilage of the fetal rat mandible

We investigated the histochemical localisation of versican, aggrecan and hyaluronan in the developing condylar cartilage of the fetal rat mandible at d 15–17 of gestation. At d 15 of gestation, immunostaining for versican was detected in the anlage of the future condylar process (condylar anlage), although the staining intensity showed a considerable regional variation. At d 16 of gestation, a metachromatically stained matrix firstly appeared in the condylar anlage. Aggrecan, hyaluronan and versican were simultaneously detected in this newly formed condylar cartilage. At d 17 of gestation, immunostaining for versican became restricted to the perichondrium and was barely detected in the cartilage. Colocalisation of versican and aggrecan was also seen in the cranial base cartilage at d 14 of gestation. These results indicate that although versican is replaced by aggrecan during the transition from prechondrogenic tissue to cartilage, both molecules were temporally colocalised in the newly formed cartilage. A hyaluronan-rich, low-versican area was identified in the posterior end of the condylar anlage during d 15–17 of gestation. The existence of this area is a unique structural feature of the developing condylar cartilage.     

4F2hc表达与人脑胶质瘤病理级别增殖和血管形成的关系

  目的  探讨细胞表面抗原4F2重链(4F2 heavy chain, 4F2hc)在人脑胶质瘤组织中的表达水平及其与胶质瘤病理学特征、细胞增殖以及血管形成的关系。  方法  采用免疫组化方法检测4F2hc、Ki-67和CD34在62例人脑胶质瘤组织中的表达, 计数Ki-67标记指数(Ki-67 LI)和微血管密度(MVD)。  结果  4F2hc在胶质瘤中高表达, 其免疫阳性染色既定位于瘤细胞也定位于血管内皮; 4F2hc表达随胶质瘤病理级别升高而明显增强(P=0.001), 在高度恶性胶质瘤中4F2hc表达明显强于低度恶性胶质瘤(P=0.002);4F2hc表达与胶质瘤Ki-67标记指数存在明显正相关(P=0.003), 但与微血管密度无明显相关性(P=0.214)。  结论  4F2hc与胶质瘤的发生和发展关系密切, 可能在胶质瘤的恶性增殖过程中具有重要作用。      

Impact of COVID-19 on the Volume of Acute Stroke Admissions: A Nationwide Survey in Japan

This study aimed to measure the impact of the COVID-19 pandemic on the volumes of annual stroke admissions compared with those before the pandemic in Japan. We conducted an observational, retrospective nationwide survey across 542 primary stroke centers in Japan. The annual admission volumes for acute stroke within 7 days from onset between 2019 as the pre-pandemic period and 2020 as the pandemic period were compared as a whole and separately by months during which the epidemic was serious and prefectures of high numbers of infected persons. The number of stroke patients declined from 182,660 in 2019 to 178,083 in 2020, with a reduction rate of 2.51% (95% confidence interval [CI], 2.58%-2.44%). The reduction rates were 1.92% (95% CI, 1.85%-2.00%; 127,979-125,522) for ischemic stroke, 3.88% (95% CI, 3.70%-4.07%, 41,906-40,278) for intracerebral hemorrhage, and 4.58% (95% CI, 4.23%-4.95%; 13,020-12,424) for subarachnoid hemorrhage. The admission volume declined by 5.60% (95% CI, 5.46%-5.74%) during the 7 months of 2020 when the epidemic was serious, whereas it increased in the remaining 5 months (2.01%; 95% CI, 1.91%-2.11%). The annual decline in the admission volume was predominant in the five prefectures with the largest numbers of infected people per million population (4.72%; 95% CI, 4.53%-4.92%). In conclusion, the acute stroke admission volume declined by 2.51% in 2020 relative to 2019 in Japan, especially during the months of high infection, and in highly infected prefectures. Overwhelmed healthcare systems and infection control practices may have been associated with the decline in the stroke admission volume during the COVID-19 pandemic.     

Intraoperative Functional Mapping and Monitoring during Glioma Surgery

Glioma surgery represents a significant advance with respect to improving resection rates using new surgical techniques, including intraoperative functional mapping, monitoring, and imaging. Functional mapping under awake craniotomy can be used to detect individual eloquent tissues of speech and/or motor functions in order to prevent unexpected deficits and promote extensive resection. In addition, monitoring the patient’s neurological findings during resection is also very useful for maximizing the removal rate and minimizing deficits by alarming that the touched area is close to eloquent regions and fibers. Assessing several types of evoked potentials, including motor evoked potentials (MEPs), sensory evoked potentials (SEPs) and visual evoked potentials (VEPs), is also helpful for performing surgical monitoring in patients under general anesthesia (GA). We herein review the utility of intraoperative mapping and monitoring the assessment of neurological findings, with a particular focus on speech and the motor function, in patients undergoing glioma surgery.     

Acute renal failure after exercise in a child with renal hypouricemia

We describe a 15 year old boy with renal hypouricemia who developed acute renal failure after a school athletics meeting, accompanied by appendicitis. During acute renal failure, the highest level of uric acid was 5.0 mg/dL, creatinine 7.9 mg/dL and urea nitrogen 58.6 mg/dL. After recovery, the serum uric acid fell to 0.9 mg/dL and the fractional excretion of uric acid (FEu_A) exceeded the normal range. The probenecid and pyrazinamide tests showed that the patient had a total defect of uric acid reabsorption. This case suggested that strenuous exercise could be responsible for acute renal failure in patients with renal hypouricemia.