[Research progress on neurotoxicity induced by metal pollutants through astrocytes]

Metal pollutants in the natural environment and industrial environment can enter organisms through the respiratory tract and digestive tract causing adverse health effects. Many kinds of literatures confirm that metal pollutants have neurotoxicity. Recent studies have showed that astrocytes play an important role in neurotoxicity induced by metal pollutants. In this review, the latest progress of neurotoxicity induced by lead, mercury, cadmium, antimony and copper through astrocytes in recent years is summarized, which provides a new clue for the neurotoxicity research of metal pollutants.

Advances in Dyslipidaemia Treatments: Focusing on ApoC3 and ANGPTL3 Inhibitors

Apolipoprotein C3 (apoC3) and angiopoietin-like protein 3 (ANGPTL3) inhibit lipolysis by lipoprotein lipase and may influence the secretion and uptake of various lipoproteins. Genetic studies show that depletion of these proteins is associated with improved lipid profiles and reduced cardiovascular events so it was anticipated that drugs which mimic the effects of loss-of-function mutations would be useful lipid treatments. ANGPTL3 inhibitors were initially developed as a treatment for severe hypertriglyceridaemia including familial chylomicronaemia syndrome (FCS), which is usually not adequately controlled with currently available drugs. However, it was found ANGPTL3 inhibitors were also effective in reducing low-density lipoprotein cholesterol (LDL-C) and they were studied in patients with homozygous familial hypercholesterolaemia (FH). Evinacumab targets ANGPTL3 and reduced LDL-C by about 50% in patients with homozygous FH and it has been approved for that indication. The antisense oligonucleotide (ASO) vupanorsen targeting ANGPTL3 was less effective in reducing LDL-C in patients with moderate hypertriglyceridaemia and its development has been discontinued but the small interfering RNA (siRNA) ARO-ANG3 is being investigated in Phase 2 studies. ApoC3 can be inhibited by the ASO volanesorsen, which reduced triglycerides by >70% in patients with FCS and it was approved for FCS in Europe but not in the United States because of concerns about thrombocytopaenia. Olezarsen is an N-acetylgalactosamine-conjugated ASO targeting apoC3 which appears as effective as volanesorsen without the risk of thrombocytopaenia and is undergoing Phase 3 trials. ARO-APOC3 is an siRNA targeting apoC3 that is currently being investigated in Phase 3 studies.

[Efficacy of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy for pseudomyxoma peritonei]

Objective: To evaluate the efficacy and safety of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) in the treatment of pseudomyxoma peritonei (PMP). Methods: In this descriptive case series study, we retrospective analyzed the records of PMP patients treated with CRS and HIPEC between January 2013 and June 2023 at Affiliated Cancer Hospital and Institute of Guangzhou Medical University. The inclusion criteria were as follows: (1) Aged 18 to 75 years and nonpregnant women. (2) Histologically confirmed diagnosis of pseudomyxoma peritonei. (3) Karnofsky Performance Scale (KPS)>70. (4) The functions of major organs such as the heart, liver, lungs, and kidneys can tolerate major surgery for long periods of time. (5) No evidence of extra-abdominal metastasis. Patients with extensive intra-abdominal adhesions or severe infectious diseases were excluded. The main outcomes were overall survival (OS) and postoperative major complications. The postoperative major complications were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 5.0). We used the peritoneal cancer index (PCI) score to quantitatively assess the peritoneal metastases and the completeness of cytoreduction (CCR) score at the end of surgery (CCR-0 and CCR-1 considered to be complete CRS). Results: A total of the 186 PMP patients with a median age of 56 (interquartile range extremes (IQRE), 48-64) years were included, 65 (34.9%) males and 121 (65.1%) females. The median peritoneal cancer index (PCI) score was 28 (20-34). Appendiceal origin accounted for 91.4%. Histological types were low grade in 99 patients (53.2%), high grade in 57 patients (30.6%), and 55 patients (29.6%) received complete cytoreduction (CCR-0/1). The median operative duration was 300 (211-430) minutes for all patients. Treatment-related 30-day mortality was 2.7%; 90-day mortality 4.3%; reoperation 1.6%; and severe morbidity 43.0%. Within the entire series, anemia(27.4%), electrolyte disturbance(11.6%), and hypoalbuminemia(7.5%) were the most frequent major complications (grade 3-4). The incidences of gastrointestinal anastomotic leakage, abdominal bleeding, and abdominal infection were 2.2%, 2.2%, and 4.3%, respectively. After a median follow-up of 38.1 (95%CI:31.2-45.1) months, the 5-year OS was 50.3% (95%CI: 40.7%-59.9%) with a median survival time of 66.1 (95%CI: 43.1-89.1) months. The survival analysis showed that patients with pathological low grade, low PCI, and low CCR score had better survival with statistically significant differences (all P<0.05). Further stratified into complete and incomplete CRS subgroups, the 5-year OS of the CCR-0 and CCR-1 subgroups was 88.9% (95%CI: 68.3%-100.0%) and 77.6% (95%CI: 62.7%-92.5%), respectively; and 42.0% (95%CI: 29.5%-54.5%) in the CCR-2/3 subgroup. Conclusions: CRS and HIPEC may result in a long-term survival benefit for PMP patients with acceptable perioperative morbidity and mortality. This strategy, when complete CRS is possible, could significantly prolong survival for strictly selected patients at experienced centers.

The flavonoids induce the transcription of mRNA encoding erythropoietin in cultured embryonic stem cells via the accumulation of hypoxia-inducible factor-1α

Flavonoids are the most common phytochemicals in vegetables and herbal products. The beneficial functions of flavonoids in the brain and erythropoietic system have been proposed. Erythropoietin (EPO) is a potent protective agent in the brain; but which has difficulty to cross the blood brain barrier (BBB). Here, about 60 flavonoids were screened for their potential activation on the transcription of EPO mRNA in the neuronal embryonic stem cell lines, NT2/D1 and PC12. Amongst the screened flavonoids, formononetin, calycosin, ononin, chrysin, baicalein and apigenin showed robust up regulation of EPO production via enhancement of hypoxia response element (HRE) activity in cultured embryonic stem cells. In addition, the flavonoids showed activation of HRE activity by having increased accumulation of HIF-1α, but not on level of HIF-1β, in the cultures. The accumulation of HIF-1α was attributed to up regulation of HIF-1α mRNA and blockade of HIF-1α degradation upon treatment of the flavonoids. These results suggested a promising trend of developing commercial products of flavonoids as food supplements tailored for brain health.

Identification of potential immunomodulators from Pulsatilla decoction that act on therapeutic targets for ulcerative colitis based on pharmacological activity, absorbed ingredients, and in-silico molecular docking

BACKGROUND

Pulsatilla decoction (Bai-Tou-Weng-Tang, BTWT) is a classic formula prescription of a traditional Chinese medicine that is used to treat ulcerative colitis (UC). However, its active components and underlying mechanism of action remain unclear. In the present study, we aimed to identify potential immunomodulators from BTWT that act at therapeutic targets for UC.

METHODS

The protective effects of BTWT granules were examined in mice with colitis induced by dextran sulfate sodium. The absorbed components of BTWT were identified using LC-MS, and selected protein targets of these components in UC were investigated using molecular docking.

RESULTS

Oral administration of BTWT granules significantly alleviated disease severity and colon shortening, and inhibited the inflammatory response in mice with chronic colitis. In these mice, 11 compounds from the BTWT granules were detected in the serum and/or colon. The molecular docking study demonstrated that compounds from Radix pulsatillae, such as anemoside A3, interacted with STAT3 and S1PR1; compounds from Rhizoma coptidis and/or Cortex phellodendri, such as palmatine, interacted with JAK3, PD-1, and PD-L1; and components of Cortex fraxini such as aesculin interacted with S1PR1, JAK3, STAT3 and PD-L1. Further in-vitro experiments showing that the compounds inhibited TNF-α and IL-6 production and STAT3 activation in RAW 264.7 cells suggested that these compounds have immunomodulatory activities.

CONCLUSION

We revealed for the first time that 11 absorbed ingredients from BTWT were immunomodulators against therapeutic targets for UC. These findings suggest that the identified compounds are the active components of BTWT, and the identified protein targets underlie the mechanism of action of BTWT against UC.

Visual analysis and evaluation of clinical research on Traditional Chinese medicine compounds in treating insomnia of Yin deficiency syndrome

ETHNOPHARMACOLOGICAL RELEVANCE

Insomnia is a common form of sleep disorder. Traditional Chinese medicine (TCM) compounds have definite curative effects and a low incidence of adverse reactions, which is recognized to be an effective intervention means for the treatment of insomnia.

AIM OF THE STUDY

Based on mining the clinical research data of treating insomnia of yin deficiency syndrome (IYDS) with TCM compounds systematically, the study is to analyze the research hotspots and development trends in this field, explore the medication rule, evaluate the quality of research, so as to provide reference and direction for clinical application and scientific research in this field.

MATERIALS AND METHODS

The relevant literature was retrieved and managed by evidence-based medicine strategy and EndNote software respectively. The bibliometric method was used to mine and analyze data characteristics. The VOSviewer software was used to make visual knowledge maps, the IBM SPSS Modeler software was used for association rule analysis of herbs, and the Cochrane tool and MINORS scale were used for quality analysis of literature.

RESULTS

(1) A total of 184 related studies were included according to the inclusion and exclusion criteria. (2) The research popularity showed a dynamic upward trend and the research hotspot showed a trend of migration and refinement, etc. (3) The commonly used herbs in this field were Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F.Chow, etc; the commonly used TCM prescriptions were Huanglian Ejiao Decoction, etc; the commonly used dosage forms were traditional decoction, etc; the commonly used combinations of herbs included Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F.Chow-Poria cocos（Schw.）Wolf, etc. (4) The rate of the studies containing ethical review numbers and clear inclusion standards did not reach 50%, and the risk bias of methodological was high. However, a separate analysis of data showed that the specification of study design was on the rise obviously in recent years, and Meta-analysis and sensitivity analysis could confirm the effectiveness and stability of clinical efficacy which was the key indicator in treating IYDS with TCM prescriptions. There were significant differences among administration protocols of different clinical studies of the same name TCM compounds. However, the scientific significance of each unique dosing regimen were expected to be elaborated or discussed.

CONCLUSION

The clinical research number of TCM compounds treating IYDS was in a dynamic upward trend, and the outcome indicators tended to be diversified and detailed. The dosage forms mainly included decoction, supplemented by Chinese patent medicine. The design of clinical studies in this field was not standardized enough, but the key indicators were scientific and stable. We expected that later studies could pay more attention to improving the standardization of trial design, reducing the risk bias in the process of methodological design, conducting high-quality standardized multicenter, large-sample randomized controlled clinical trials to provide scientific evidence with high evidentiary strength, establishing the recognized administration protocols for the same name TCM prescriptions or clarifying the targeting of different protocols, and promoting the application and popularity of TCM compounds in treating IYDS.

[Long-term outcome of 48 unoperated adult patients with Ebstein's anomaly]

Objective: To analyze the long-term outcome of unoperated Ebstein's anomaly (EA) patients aged over 18 years, and to evaluate the related factor of outcomes. Methods: The data of 48 unoperated EA patients from March 2004 to December 2008 in the First Hospital of Tsinghua University, were analyzed. The clinical data of the patients were collected, and patients received regular echocardiography, ECG and chest X-ray examinations. Septal leaflet attachment ratio (SLAr) was calculated based on transthoracic echocardiography imagines. The patients were divided into 3 groups according to SLAr: SLAr<0.45 (n=18), 0.45≤SLAr≤0.60 (n=21) and SLAr>0.60 (n=9). Chest X-ray was used for measurement of cardiothoracic ratio (CTR). Kaplan Meier survival curve was used to calculate the long-term survival rate. Cox proportional hazards regression model was used to analyze the influencing factors of death. Results: There were 19 males, and the mean age at diagnosis was (21.3±11.1) years. Forty-two patients (87.5%) were complicated with arrhythmia, including W-P-W syndrome (n=4), supraventricular tachycardia (n=16), right bundle branch block (n=37), and atrial fibrillation (n=2). The mean duration of follow-up was (148.8±16.8) months, the follow-up rate was 100% with no loss-to-follow up. Nine cases (18.8%) died during follow-up: 6 cases (12.5%) died of cardiac origin, including 3 cases of heart failure, 1 case of arrhythmia, and 2 cases of sudden death; 1 case died of accident; 2 cases died from unknown causes. During the follow-up period, the survival rates were 17/18, 19/21 (90.5%) and 3/9 in the SLAr<0.45, 0.45≤SLAr≤0.60 and SLAr>0.60 group, respectively. According to Kaplan-Meier survival curve, the 5-year survival rates among the three groups were 100%, 100% and 78%, respectively. The 10-year survival rates among the three groups were 94%, 95% and 44%, respectively. Decreased activity tolerance and heart failure were found in 7 patients (6 patients in SLAr>0.60 group and 1 patient in 0.45≤SLAr≤0.60 group). Two patients had cerebrovascular embolism. There were 3 cases with tachyarrhythmia lasting more than 24 hours. Cox regression analysis showed that the risk of death was higher in patients with SLAr>0.60 than in patients with SLAr<0.45 (HR=12.375, 95%CI 1.692-22.146, P=0.015); the risk of death in patients with CTR≥0.65 was 1.306 times higher than that in patients with CTR<0.65 (HR=1.306, 95%CI 0.417-12.754, P=0.038). Conclusions: EA patients often combines with arrhythmia. For unoperated EA patients, SLAr>0.60 and CTR≥0.65 are risk factors of death. EA patients with arrhythmia should be actively treated with drugs or radiofrequency ablation.

Improvac induces immunocastration by affecting testosterone levels and disrupting spermatogenesis in male broiler chickens

Immunocastration (vaccination against Gonadotropin-releasing hormone (GnRH)) has been regarded as a friendly substitution to physical castration in animals. To date, a few studies have reported the use of Improvac for immunocastration in boar and one study in broiler chickens; however, there is an apparent dearth of scientific evidence regarding the application of Improvac for immunocastration in birds. In the present study, we evaluated the effects of Improvac-based immunocastration on testosterone levels and spermatogenesis in broiler chickens and the effects of Improvac on the expression of genes related to testosterone biosynthesis and metabolism as well as spermatogenesis. The birds were randomly divided into 4 groups (n = 30 each): Control group (non-immunized), Early group (immunized with Improvac at week 3), Late group (immunized with Improvac at week 6), and Early + Late group (immunized with Improvac at weeks 3 and 6). Immunization with Improvac significantly improved the average daily gain compared to the Control group. Of note, following Improvac vaccination, the reproductive efficiency was significantly decreased in male broiler chickens. Furthermore, parameters such as the serum testosterone concentration, spermatogenesis, and the expression levels of genes related to testosterone metabolism (Cyp17A1, Cyp19, HSD3B1, and HSD17B3) and spermatogenesis (Cyclin A1 and Cyclin A2) were significantly reduced in the immunized groups compared to the Control group. Taken together, these findings reveal that immunization against GnRH can be achieved, at least partially, in male broiler chickens. The results of our study also support the hypothesis of using Improvac as an alternative solution to caponization, with considerably improved animal welfare.

[Construction and in vitro verification of a new humanized anti-CD19 CAR-T cells with high affinity]

目的

构建人源化抗CD19嵌合抗原受体T细胞（CAR-T），通过体外实验验证其杀伤白血病细胞的能力。

方法

将人CD19的鼠源抗体（FMC63）进行了人源化改造，获得高亲和力的人源化CD19抗体；构建携带人源化CD19 CAR慢病毒载体，感染T细胞获得人源化CD19 CAR-T细胞（hCART19）；按不同效靶比将效应细胞[hCART19、未转染的T细胞（阴性组）及对照病毒转染的T细胞（对照组）]及靶细胞（CHO-K1-CD19及Raji细胞）混合培养，LDH释放实验及ELISA法检测hCART19杀伤白血病细胞的能力及细胞因子释放水平；白血病小鼠模型检测hCART19的杀瘤效果。

结果

LDH释放实验证实随着效靶比的不断增加，对靶细胞的杀伤率逐渐增加，当效靶比为10∶1时hCART19组的杀伤率最大，在Raji细胞中为（87.56±1.99）%，明显高于阴性组[（19.31±1.16）%]及对照组[（21.35±1.19）%]（P值均<0.001）。ELISA法检测显示Raji细胞作为靶细胞时，hCART19组IL-2水平[（10.56±0.88）pg/ml]及IFN-γ[（199.02±12.66）pg/ml]较阴性组[IL-2：（3.55±0.26）pg/ml；IFN-γ：（37.63±0.85）pg/ml]及对照组[IL-2：（2.92±0.32）pg/ml；IFN-γ：（52.07±3.33）pg/ml]明显升高（P值均<0.001）。以上实验在CHO-K1-CD19细胞作为靶细胞时也出现了相似的结果。给予白血病小鼠模型尾静脉分别注射hCART19、对照病毒转染的T细胞及未转染的T细胞，结果显示hCART19组小鼠存活时间>40 d，另外两组小鼠在20~30 d全部死亡，差异有统计学意义（χ²=11.73，P=0.008）。

结论

成功构建了具有抗白血病活性的人源化CD19 CAR-T细胞，为下一步的临床研究奠定了基础。

[Effects of PSMB5 on proliferation and bortezomib chemo-resistance in human myeloma cells and its related molecular mechanisms]

Objective: To investigate the effects of proteasome beta 5 subunit (PSMB5) on proliferation and bortezomib (BTZ) chemo-sensitivity of multiple myeloma (MM) and its related molecular mechanisms. Methods: We used two MM cell lines, RPMI 8226 and BTZ drug-resistant cell line RPMI 8226/BTZ100 (hereinafter referred to as BTZ100) , as the research object. PSMB5 was overexpressed or knocked down in two myeloma cell lines via lentivirus transfection. CCK8 assay was used to detect the impact of PSMB5 on cell viability and bortezomib sensitivity in human myeloma cells; Using flow cytometry to test the effects of PSMB5 on apoptosis rate of human myeloma cells under the treatment of bortezomib; Apoptosis-related gene expression of Bax, Bcl-2, p-Akt and cleaved caspase-3 were detected by Western blot. Results: ①PSMB5 overexpression and knockdown were successfully constructed in RPMI 8226 and BTZ100 cells. ②PSMB5 expression was positively correlated with cell proliferation of RPMI 8226 and BTZ100 cells (P<0.05) . ③The cell viability was lower after PSMB5 knockdown in RPMI 8226 cells than control cells under the same concentration of BTZ[IC(50) at 24 h: (7.01±0.47) and (9.64±0.55) nmol/L respectively, t=6.289, P=0.003]. The cell viability was higher after PSMB5 overexpression in RPMI 8226 cells than control cells under the same concentration of BTZ[IC(50) at 24 h: (10.99±0.58) and (9.51±0.37) nmol/L respectively, t=3.724, P=0.020) . PSMB5 expression was negatively correlated with the sensitivity of RPMI 8226 cells to BTZ. The results of BTZ100 cells were similar. ④The expression of PSMB5 was negatively correlated with the apoptosis of RPMI 8226 and BTZ100 under the treatment of BTZ. ⑤Meanwhile, PSMB5 knockdown could increase the expression of pro-apoptosis gene Bax and cleaved caspase-3 and decrease the expression of anti-apoptotic gene Bcl-2 and p-Akt. PSMB5 over-expression has the opposite results. Conclusion: PSMB5 knockdown could improve the bortezomib sensitivity of MM cells via activation of apoptosis signaling. PSMB5 may be a potential therapeutic target for MM.

[To promote the sustainable development of surgical treatment for congenital heart disease by innovation and practice]

Due to the tireless efforts of medical staff, we have made great progress in the surgical treatment of congenital heart disease in recent years. A lot of new experiences has been accumulated and many new methods have been created in the diagnosis and treatment of congenital heart disease in neonates, minimal invasive surgical technique, hybrid procedure and the surgical treatment of complicated congenital heart disease. It is proved that innovation and practice are the basis of the surgical treatment of congenital heart disease.

[The outcomes of operation for 237 patients with Ebstein anomaly]

Objective: To evaluate the early and long-term outcomes cardiac surgery of patients with Ebstein anomaly. Methods: The clinic data of 237 patients with Ebstein anomaly received surgical procedures from March 2004 to December 2017 at Department of Cardiac Surgery, First Hospital of Tsinghua University was analyzed retrospectively. There were 105 male and 132 female patients with age of (19.4±16.7) years (ranging from 3 months to 64 years). The surgical procedures include anatomical repair in 188 patients, one and a half ventricle repair in 37 patients, tricuspid valve repair in 4 patients, tricuspid valve replacement in 10 patients, and Fontan procedure in 3 patients (total cavopulmonary connection in 2 patients; Glenn procedure in 1 patient). Results: The early mortality was 2.1% (n=5). One case of atrioventricular (0.4%) newly occurred. There were 228 patients available to follow-up. The range of follow-up duration was 3 to 168 months. Late survival was 99.1% (2 cases of late death) at 10 years. Three patients received reoperation (1.3%), including tricuspid valve repair of 1 patient and one and a half ventricle repair of 2 patients). Indication of tricuspid valve regurgitation improved from 3.6±0.3 to 1.5±0.4. Survival rate at 5 and 10 years was 98.6% and 98.2%, respectively. Conclusions: The principle of the techniques is to reconstruct the tricuspid valve and right ventricle anatomically. For most cases, the anatomical repair was demonstrated with low mortality, less complications and excellent durability at long-term follow-up. If the tricuspid valve is severely hypoplastic, one and a half ventricle repair and valve replacement may be alternatie.

CXCR4 antagonist AMD3100 enhances the response of MDA-MB-231 triple-negative breast cancer cells to ionizing radiation

Radiation therapy (RT) is one of the primary modalities for triple-negative breast cancer (TNBC) treatment. However, due to the pro-metastatic potential of radiation and the intrinsic radiation resistance of some tumors, many patients experience RT failure, which leads to cancer relapse and distant metastasis. This preclinical study evaluated the efficacy of the antagonist of the SDF-1 receptor CXCR4, AMD3100, as a radiosensitizer in TNBC models. The combined effect of ionizing radiation and AMD3100 was determined in vitro by surviving fraction, cell cycle distribution, Bax and Bcl-2 expression, and apoptosis assays in a TNBC cell line (MDA-MB-231). For in vivo studies, human xenograft athymic nude mice were used. Treatment of TNBC cells with AMD3100 significantly augmented cellular radiosensitivity. Radiosensitivity was enhanced specifically through increased Bax expression, reduced Bcl-2 expression, prolonged G2-M arrest, and increased apoptosis. Combined treatment with AMD3100 and irradiation also enhanced tumor growth delay, with an enhancement factor ranging from 1.5 to 1.8. These findings support the evaluation of antagonists of the SDF-1 receptor CXCR4, such as AMD3100, as potent radiosensitizers in TNBC.

[The effects of different tidal volume ventilation on right ventricular function in critical respiratory failure patients]

Objective: To observe and explore the effects of different tidal volume (VT) ventilation on right ventricular (RV) function in patients with critical respiratory failure. Methods: Consecutive respiratory failure patients who were treated with invasive ventilator over 24 h in the Department of Critical Care Medicine at the Fourth Hospital of Hebei Medical University from June to December in 2015 were enrolled in this study.Clinical data including patients' vital signs, ventilator parameters and RV echocardiography were collected within 6 h (D0), day1(D1), day2 (D2) and day3 (D3) after ventilation started.According to the VT, patients with acute respiratory distress syndrome (ARDS) were assigned to low VT group [S6, ≤6 ml/kg predicted body weight (PBW)] and high VT group (L6, >6 ml/kg PBW), while non-ARDS patients were also assigned to low VT group (S8, ≤8 ml/kg PBW) and high VT group (L8, >8 ml/kg PBW). Results: A total of 84 patients were enrolled in this study.44.2% ARDS patients and 58.5% non-ARDS patients were in low VT groups.After ventilation, tricuspid annulus plane systolic excursion(TAPSE)decreased progressively in S6 [from 18.30(16.70, 20.70) mm to 17.55(15.70, 19.50) mm, P=0.001], L6 [from 19.50(17.00, 21.00) mm to 16.30(15.00, 18.00) mm P=0.001], S8[from 18.00(16.00, 21.00) mm to 16.50(15.50, 18.00) mm, P=0.001] and L8 [from 19.00(17.50, 21.50) mm to 16.35(15.15, 17.00) mm, P=0.001] groups.However, TAPSE decreased less in small VT groups (S6 and S8) than those of in large VT groups (S8 and L8) without significant differences.There were not statistical differences between different VT groups in terms of ventilation days, including right ventricle area/left ventricle area (RV(area)/LV(area)), TAPSE, peak mitral flow velocity of the early rapid filling wave (E), peak mitral flow velocity of the late rapid filling wave (A), early diastolic velocity of the tricuspid annulus (e'), pulmonary artery systolic pressure, inferior vena cava diameter (all P>0.05). Compared to L6 group, low VT (S6 group) resulted in decreased mortality at 28 days [1/19 vs 37.5%(9/24), P=0.014]. There were not statistical differences between different VT groups in terms of ventilation days, length of intensive care unit stay, length of hospital stay (all P>0.05). Logistic regression analysis showed that VT could be the independent factor of TAPSE (OR=1.104, 95%CI 0.100-1.003, P=0.049). Conclusions: Positive pressure mechanical ventilation resulted in RV systolic dysfunction .Lower VT may have the protective effect on RV function. Trial registration: Chinese Clinical Trial Registry, ChiCTR-POC-15007563.

[Therapeutic effect of miR-489 in a mouse model of silica-induced matured pulmonary fibrosis]

Objective: To explore the potential therapeutic role of miR-489 in silica-induced pulmonary fibrosis mouse models. Methods: A total of 32 C57BL/6 male mice were randomly divided into four groups: saline, silica, silica plus miRNA control and silica plus miR-489 agomir (n=8 in each group) . The mice were instilled with silica particles suspended in saline or sterile saline intratracheally. Subsequently, miR-489 agomir or miRNA control was injected via the tail vein into each mouse at days 28, 35, 42 and 49, the miR-489 levels, histological examination, collagen deposition, fibrotic biomarkers (E-cadherin, α-SMA, Vimentin, Fibronectin) and transforming growth factor-β(1) (TGF-β(1)) protein levels in mouse lung tissues were measured. Results: miR-489 levels in silica plus miR-489 group were significantly increased in lung tissues compared with silica plus miRNA control group (P<0.05) . Histological examination showed attenuated inflammation, less severe fibrotic foci and less destruction of alveolar architecture in the silica plus miR-489 group. Additionally, both the severity and distribution of lung lesions were ameliorated in silica plus miR-489 group compared with the silica plus miRNA control group (P<0.05) . The collagen deposition and hydroxyproline levels in silica plus miR-489 group were significantly decreased compared with the silica plus miRNA control group (P<0.05) . These changes were supported by decreased protein levels of α-SMA, Vimentin, Fibronectin, TGF-β1 along with increased protein levels of E-cadherin in silica plus miR-489 group (P<0.05) . Conclusion: Our data indicate that the upregulation of miR-489 has potential therapeutic role in silica-induced pulmonary fibrosis in vivo, which may be associated with the depression of TGF-β1 release.

High-dose calcium channel blocker (CCB) monotherapy vs combination therapy of standard-dose CCBs and angiotensin receptor blockers for hypertension: a meta-analysis

In this study, we evaluated the efficacy and safety of high-dose calcium channel blocker (CCB) monotherapy and standard-dose CCBs combined with angiotensin receptor blockers (ARBs) for patients with hypertension. A comprehensive search of PubMed, Embase and the Cochrane Central Register of Controlled Trials was performed in December 2015. Randomized controlled trials designed to identify the above goal were included. Thirteen trials including 2371 patients were identified. The standard-dose CCB/ARB combination resulted in a greater reduction of systolic blood pressure (WMD -2.52, 95% confidence interval (CI): -3.76 to -1.28) and diastolic blood pressure (weighted mean difference (WMD) -2.07, 95% CI: -3.73 to -0.42) compared to high-dose CCB monotherapy. The overall hypertension control rate for the CCB/ARB combination was higher than that for CCB monotherapy (relative risk (RR): 1.17, 95% CI: 1.08-1.26). Furthermore, the CCB/ARB combination treatment yielded significantly fewer overall adverse events (RR: 0.84, 95% CI: 0.74-0.95), oedema (RR: 0.31; 95% CI: 0.18-0.52) and rash (RR: 0.27, 95% CI: 0.08-0.96, P=0.04) than did CCB monotherapy. The standard-dose CCB/ARB combination is superior to high-dose CCB monotherapy for lowering blood pressure and reducing adverse events in hypertensive patients. Future research should focus on the cost-effectiveness and long-term effects of these two treatment strategies for patients with hypertension.

Linkage analysis of SNPs in IGFBP-6 and its relation with the body sizes of pig

Insulin-like growth factor binding protein-6 (IGFBP-6) is a member of the IGFBP family, which is known to be a key factor in regulating the effect of insulin-like growth factor-2 (IGF-2) on the animal growth and development. Gene sequences of 3'-untranslated regions (UTR) and exon 4 of IGFBP-6 may influence the expression and proteolysis of IGFBP-6. In this study, 551 bp of the IGFBP-6 (including 257 bp of intron 3, exon 4, and 170 bp of 3' UTR) were sequenced and compared in the Bama and Tibetan mini-pigs, the Landrace and Large White pigs, and the Northeast wild boars. Six single nucleotide polymorphisms (SNPs) were detected in the IGFBP-6, in which T593C, T636C, and T745C were in intron 3, A67G was in exon 4, and G37A was in 3' UTR. T636C, T745C, and A67G were in linkage and formed four kinds of haplotypes, with CCT being the dominant haplotype in the mini-pigs; however, the haplotype block was not formed in the Landrace pigs and Large White pigs or the Northeast wild boars. Based on the above results, we concluded that the SNPs and haplotype of the IGFBP-6 may be related to the mini-size formation of the pig.

Clinical analysis of diagnosis and treatment of 13 cases with cesarean scar pregnancy

OBJECTIVE

To explore effective methods in diagnosing and treating cesarean scar pregnancy (CSP) after cesarean section.

MATERIALS AND METHODS

The clinical data of 13 cases with CSP who were admitted to the present hospital from October 2009 to February 2012 were retrospectively analyzed.

RESULTS

The agreement diagnostic rate was 92.3% (12/13). On the basis of transvaginal color Doppler ultrasonography 12 patients had medical therapy combined with uterine artery embolization (UAE) and curettage was successfully performed. One patient was diagnosed through an emergency setting due to symptomatology.

CONCLUSION

Early accurate diagnosis of CSP is the key to perform proper and successful treatment.

Monitoring and evaluation of removal of pathogens at municipal wastewater treatment plants

The concentrations and removal of Cryptosporidium, Giardia, and microbial indicators, including somatic coliphages and fecal coliforms were investigated through the wastewater treatment processes at three municipal wastewater treatment plants in Beijing, China. The experimental results showed that the concentrations of Cryptosporidium in untreated wastewater, primary treatment effluent, secondary treatment effluent, tertiary treatment effluent were 33-600, 67-333, 0-9 and 0-0.4 oocysts L(-1), and that of Giardia were 130-3,600, 533-2,033, 0-32 and 0-2.1 cysts L(-1), respectively. The reduction ratios of Cryptosporidium and Giardia by the primary treatment process were 0.12 log and 0.18 log, respectively. Oxidation ditch process had higher reduction efficiency to Cryptosporidium and Giardia than anaerobic-anoxic-oxic process and conventional activated sludge process, probably because of longer retention time and higher sludge concentration. Membrane ultrafiltration had a notably better efficiency to reduce microorganisms, especially Cryptosporidium and Giardia, than conventional flocculation sedimentation and sand filtration process, as the tertiary treatment. Comparing with total coliforms, fecal coliforms and heterotrophic bacteria, concentration of somatic coliphages was correlated better with that of Cryptosporidium and Giardia in untreated wastewater and secondary treatment effluent.

Influence of ultraviolet-C on structure and function of Synechococcus sp. PCC 7942 photolyase

In this work, an over-expressed cyclobutane pyrimidine dimer (CPD) photolyase of Synechococcus sp. PCC 7942 was used to investigate UV-C (ultraviolet irradiation of C-region) influence on photoreactivation. In vivo photoreactivation experiments indicated that the survival rate decreased from 100 to 2.6% when the UV-C flux was increased from 1.1 to 68.5 muW/cm2. It seemed that the photolyase was easily inactivated at UV-C intensities >or=25.5 muW/cm2. Spectrometric analysis indicated that tertiary structure of the photolyase changed evidently when the UV-C fluxes were >or=25.5 muW/cm2, while the secondary structure was almost unchanged even at 170 muW/cm2. Band shift assay indicated that catalytic activity of the photolyase was impaired at fluxes >or=25.5 muW/cm2, but no significant influence on DNA-binding activity was observed. These results suggest that photoreactivation is efficient at UV-C fluxes <or=25.5 muW/cm2, but would be impaired by intense UV-C irradiation due to structure changes of the photolyase.

Mesenchymal stem cellular adhesion and cytotoxicity study of random biopolyester scaffolds for tissue engineering

Mesenchymal stem cells (MSCs) were isolated from the bone marrow of rabbits and inoculated respectively on 3D scaffolds of poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) (PHBV), poly(butylenes succinate) (PBS) and different blends (100/0, 80/20, 50/50, 20/80, 0/100) (Wt%) in vitro. It was found that the (50/50) blends possessed the best performance on adhesion and cytotoxicity of MSCs. The scanning electronic microscopy (SEM) results showed that the (50/50) blends had the appropriate roughness for MSCs to attach and grow, which may be used as a suitable biomaterial to create small caliber vascular grafts.

Anomalous origin of the pulmonary artery from the right coronary artery

A 5-year-old boy who had an anomalous origin of a stenotic pulmonary artery from the right coronary artery with ventricular septal defect and pulmonary atresia is reported. The diagnosis was made at operation. Successful repair was achieved for the complex anomaly by using a pulmonary artery homograft as a conduit and closing the ventricular septal defect.

[Qi deficiency and blood stasis and circulatory renin-angiotensin system as well as plasminogen activator inhibitor activity in rats with cardiac qi deficiency syndrome]

OBJECTIVE

To explore the relationship between cardiac Qi deficiency Syndrome and effect of circulatory renin-angiotensin system (RAS) and endogenous fibrinolytic system in rats with heart failure (HF).

METHODS

Plasma RAS levels and plasminogen activator inhibitor (PAI-1) activity were measured in 2 groups of rats: the sham-operated group (Group A) and the HF with Heart Qi deficiency Syndrome model group (Group B) established by making arteriovenous fistula. Using radioimmunoassay and chromatography, plasma renin activity (PRA) and angiotensin II (Ang II) levels and PAI-I activity were determined before, immediately after and 30 days after the surgical operation respectively.

RESULTS

After the operation was completed in Group B the left ventricular dysfunction revealed, left ventricular systolic pressure decreased and end diastolic pressure increased (P < 0.05), PRA and Ang II level and PAI-1 activity increased significantly, as compared with those in Group A and before modeling (P < 0.05). With cardiac function improved, the plasma PRA, Ang II level and PAI-1 activity lowered in Group B comparing with those immediately after modeling (P < 0.05).

CONCLUSION

The activation of RAS is associated with the endogenous fibrinolyticim balance, and play an important role in endogenous fibrinolytic system dysfunction in HF with Heart Qi deficiency Syndrome and Qi deficiency-blood stasis, which was helpful to explain that cause of hypercoagulant state in HF patients and increase the risk of suffering from embolism-thrombotic diseases, and might be the pathogenetic basis of Heart Qi deficiency induced Qi deficiency-blood stasis.

Accumulation of poly-beta-hydroxybutyrate in cyanobacterium Synechocystis sp. PCC6803

Accumulation of poly-beta-hydroxybutyrate (PHB) by photoautotrophic microorganisms makes it possible to reduce the production cost of PHB. The Synechocystis sp. PCC6803 cells grown in BG11 medium under balanced, nitrogen-starved or phosphorus-starved conditions were observed by transmission electron microscope. Many electron-transparent granules in the nitrogen-starved cells had a diameter up to 0.8 micron. In contrast, the number of granules in the normally cultured cells decreased obviously and only zero to three much smaller granules were in each cell. These granules were similar to those in bacteria capable of synthesizing PHB. They were proved to be PHB by gas chromatography after subjecting the cells to methanolysis. Effects of glucose as carbon source and light intensity on PHB accumulation in Synechocystis sp. PCC6803 under nitrogen-starved cultivation were further studied. Glucose and illumination promoted cell growth but did not favor PHB synthesis. After 7 days of growth under nitrogen-starved photoautotrophic conditions, the intracellular level of PHB was up to 4.1% of cellular dry weight and the PHB concentration in the culture broth was 27 mg/l.

Evaluation of coronary artery bypass graft patency using three-dimensional reconstruction and flow study on electron beam tomography

OBJECTIVES

To establish and evaluate two protocols for the noninvasive visualization and assessment of coronary artery bypass graft (CABG) patency on electron beam tomography (EBT).

METHODS

Two hundred fourteen consecutive patients who underwent CABG surgery were scanned using both EBT angiography with three-dimensional reconstruction and EBT flow study with time-density curve analysis.

RESULTS

There was a total of 589 CABGs evaluated in this study (10 grafts were excluded because of artifacts); 133 (98.5%) of 135 arterial grafts were patent, 345 (77.7%) of 444 saphenous vein grafts were patent. Within 5 years or 5-10 years after surgery, arterial graft patency exceeded venous graft patency (p<0.001). Three-dimensional EBT angiography achieved higher sensitivity, specificity, and accuracy (97.7%, 94.1%, and 96.7%, respectively) than EBT flow study (88.4%, 82.4%, and 85.2%, respectively) for evaluating occlusion or patency of CABGs. The intragraft flow of patent arterial and venous grafts were 4.9+/-2.2 ml/min/g and 6.9+/-2.8 ml/min/g, respectively (p<0.001).

CONCLUSION

The combination of EBT three-dimensional reconstruction and flow study can be more effectively performed in the assessment of CABG anatomy and quantification of patent CABG flow.

[A novel rabbit endothelin B receptor gene: cloning and sequence analysis]

Endothelin(ET) is the most potent mammalian vasoconstrictor identified to data. As a pathogenic factor, ET is involved in the genesis of many diseases. In this study, a pair of primers was designed and synthesized according to the human ETB receptor gene (hETBR) sequence. A 394 bp of DNA fragment was amplified by polymerase chain reaction(PCR) and labeled with alpha-32P-CTP using Random Primer-Labeling method. With this probe, rabbit lung cDNA library was screened by in situ hybridization and 11 positive clones were identified. Sequencing result showed that a complete reading frame of rabbit ETB receptor(rETBR) cDNA could be produced from three positive clones of eleven. By a series of subcloning, a recombinant plasmid including the 1326 bp of rETBR coding sequences, named pBlu Script-rETBR, was constructed. The deduced amino acid sequence indicated that the rETBR is 441 residues in length, with an expected molecular mass of approximately 49.44 kD. N-terminal 18 residues is the potential signal peptide (Score = 11.11) and therefore the molecular mass of mature rETBR is 47.65 kD with 423 amino acid residues. Analysis of the rETBR hydropathy profile indicates the presence of seven hydrophobic regions, putative transmembrane domains. Potential N-glycosylation sites are the 60th and the 118th. The structure exhibits a significant sequence and topographical similarity with G protein-coupled receptors.

Ryanodine-sensitive, thapsigargin-insensitive calcium uptake in rat ventricle homogenates

Thapsigargin is a natural product that specifically inhibits all known SERCA calcium pumps with high affinity. We investigated the effects of thapsigargin on cardiac sarcoplasmic reticulum (SR) by measuring the oxalate-supported calcium uptake rate in the unfractionated homogenate and in the isolated SR fraction. The uptake rate in both the isolated SR and unfractionated homogenate are stimulated about two-fold by preincubation with high concentrations of ryanodine, which closes the SR efflux channel. Thapsigargin stoichiometrically and completely inhibited the calcium uptake rate in the isolated SR, both in the presence and absence of SR channel blockade. In contrast, thapsigargin nearly completely inhibited the homogenate calcium uptake only in the absence of SR channel blockade; in the presence of blockade, about 20% of the uptake activity was insensitive to thapsigargin. This result unmasks a thapsigargin-insensitive, ryanodine-sensitive component of calcium uptake in the heart. This activity is in an oxalate-permeable pool and is inhibited by cyclopiazonic acid, another inhibitor of the SERCA calcium pumps. There was no TG-insensitive activity in the rat EDL muscle homogenate. The absence of thapsigargin-insensitive uptake activity in the isolated SR can be attributed to its inactivation during the isolation of the SR. The oxalate permeability and ryanodine sensitivity suggest that the TG-insensitive calcium uptake activity is closely related to the classical SR. The different thapsigargin sensitivities suggests the existence of two kinds of intracellular calcium pumps in the heart.

Flanking proline residues identify the L-type Ca2+ channel binding site of calciseptine and FS2

Calciseptine and FS2 are 60-amino acid polypeptides, isolated from venom of the black mamba (Dendroaspis polylepis polylepis), that block voltage-dependent L-type Ca2+ channels. We predicted that these polypeptides contain an identical functional site between residues 43 and 46 by searching for proline residues that mark the flanks of protein-protein interaction sites [Kini, R. M., and Evans, H. J. (1966) FEBS Lett. 385, 81-86]. The predicted Ca2+ channel binding site also occurs in closely related toxins, C10S2C2 and S4C8. Therefore, it is likely that these toxins also will block L-type Ca2+ channels. To test the proposed binding site on calciseptine and FS2, an eight-residue peptide, named L-calchin (L-type calcium channel inhibitor), was synthesized and examined for biological activity. As expected for an L-type Ca2+ channel blocker, L-calchin reduced peak systolic and developed pressure in isolated rat heart Langendorff preparations without affecting diastolic pressure or heart rate. Furthermore, L-calchin caused a voltage-independent block of L-type Ca2+ channel currents in whole-cell patch-clamped rabbit ventricular myocytes. Thus the synthetic peptide exhibits the L-type Ca2+ channel blocking properties of the parent molecules, calciseptine and FS2, but with a lower potency. These results strongly support the identification of a site in calciseptine and FS2 that is important for binding to L-type Ca2+ channels and reinforce the importance of proline brackets flanking protein-protein interaction sites.

[GABA mediated inhibitory effect of amygdala on the activity of medial geniculate body neurons]

On 10 New Zealand white rabbits immobilized with Flaxedil, the inhibitory effect of amygdaloid stimulation on the responses of medial geniculate body (MGB) neurons to tone bursts and the involved neurotransmitter mechanism were investigated with microiontophoresis technique. The results showed that application of GABA could cause a suppression of spontaneous activity of MGB neurons while GABAA antagonist bicuculline had an opposite effect. Iontophoretic injection of GABA gave an inhibitory effect on MGB neurons similar to that caused by stimulating the amygdala or the auditory cortex behind the rhinal sulcus (ACBRS), and in particular, the GABA induced suppression could be completely antagonized by application of bicuculline. Taken together, these data suggested that GABA mediated the amygdaloid inhibitory effect. It seemed unlikely that glycine was involved in the effect, since strychnine, a glycine antagonist, could not affect the descending inhibition from ACBRS area.

Effect of ischemia on the fraction of ryanodine-sensitive cardiac sarcoplasmic reticulum

The effect of 15 min of global, normothermic ischemia on cardiac sarcoplasmic reticulum (SR) was investigated using the Ca2+ uptake rate and 3H-ryanodine binding of ventricular homogenates and isolated SR vesicles. Ischemia did not affect ryanodine binding in the homogenate, while it increased it in the isolated SR vesicles. Although ischemia decreased the homogenate oxalate-supported Ca2+ uptake rate, measured in the presence of high ryanodine to close the ryanodine-sensitive efflux pathway (+RY), its decrease of the Ca2+ uptake rate, measured in the absence of ryanodine (-RY), was more marked. This finding was also observed in the isolated SR. Although inhibition of the Ca-ATPase and its coupled Ca2+ uptake by thapsigargin proportionately decreased SR Ca2+ uptake -RY and +RY, ischemia decreased the Ca2+ uptake -RY proportionately more. This result suggested that there was a greater fraction of Ca2+ uptake activity in ryanodine-sensitive vesicles after ischemia. However, ischemia also reduced the yield of SR activity in the isolated SR fraction and the results could potentially be due to differential selection of ryanodine-sensitive and ryanodine-insensitive SR in the isolation procedure. We directly tested the hypothesis that ischemia changes the fraction of Ca2+ uptake activity in the ryanodine-sensitive vesicles by estimating the Ca-oxalate capacity measured +RY and -RY. Ischemia decreased the capacity -RY much more than +RY in the homogenate, indicating that more of the SR volume and Ca2+ uptake activity was in the ryanodine-sensitive vesicles after ischemia.

Ryanodine perfusion decreases cardiac mechanical function without affecting homogenate sarcoplasmic reticulum Ca2+ uptake: comparison with the stunned heart

This study tested the hypothesis that perfusion with low concentrations of ryanodine, which opens the sarcoplasmic reticulum (SR) Ca2+ channel in a sub-conducting state, could mimic the effects of stunning on both mechanical and SR activity. Perfusion of isolated rat hearts with 10-160 nM ryanodine progressively decreased left ventricular developed pressure (LVDP) and increased end-diastolic pressure (EDP), but LVDP decreased more and EDP increased less than in the stunned heart. The effect of ryanodine perfusion on LVDP and EDP is consistent with the opening of the SR Ca2+ channel by high-affinity ryanodine binding, reducing SR Ca2+ content and interfering with mechanical function. In contrast to stunning, ryanodine perfusion did not affect the homogenate Ca2+ uptake rates measured in the presence or absence of high [ryanodine]. Perfusion with 80 nM 3H-ryanodine resulted in a large decline in LVDP, but only a small degree of ryanodine binding. Thus, prolonged opening of only a few channels affects the SR in situ, whereas this is undetectable in the homogenate. Higher levels of ryanodine binding (0.3 pmol/mg) to the in vitro homogenate also did not affect the homogenate Ca(2+)-uptake rate in the presence or absence of high [ryanodine], whereas it reduced the stimulation of Ca2+ uptake by ruthenium red. High-affinity ryanodine binding to the SR Ca2+ channel, either by perfusion or by binding after homogenisation, did not duplicate the increased Ca2+ efflux observed in the stunned heart, suggesting that the SR defect in the stunned heart is not a prolonged opening of a sub-conducting state of the SR Ca2+ channel.

[Hypoxia induced increase of MDA and echinocytes from erythrocytes in rabbit's blood with special reference to inhibition of the increase by MPEG-SOD]

When rabbits acutely exposed to hypobaric hypoxia (at imitative altitude 5,000 m, PaO2 = 6.7 kPa), the percentage of the activity of superoxide dismutase (SOD in erythrocyte; EC 1.15.1.1) decreased respectively to 86%, 76%, 81%, 84%, 55%, 81%, 84% and 95% for a period of 0.25, 0.5, 1, 2, 3, 4, 5 and 24 h hypoxia while MDA (malondialdehyde) in erythrocyte and plasma increased significantly during hypoxia periods of 1, 2, 3, 5 and 24 h (n = 5, P < 0.05, P < 0.01 vs. normoxia group). The increase of MDA in plasma could be prevented by vitamin E (V. E, i.p, 1 mg daily for 3 consecative days before hypoxia), but that in erythrocyte did not show significant change probably because the injected V.E. without vehicle cannot penetrate through the erythrocyte membrane effectively. The echinocytes from erythrocytes increased significantly after hypoxia for 24 h (n = 5, P < 0.05 vs. normoxia group). However, by injecting MPEG-SOD (monomethoxypolythlene glycol-SOD) intravenously 30 min before hypoxia, the increase of MDA (both of erythrocyte and plasma) and echinocytes (from erythrocytes) were both inhibited obviously during hypoxia for 24 h (n = 5, P < 0.05, P < 0.01 vs. hypoxia group). It is inferred that the increase of MDA and echinocytes from erythrocytes may be due to lipid peroxidation by superoxide free radicals (O2-.) generated in erythrocytes through Fenton pattern Haber-Weiss reaction during hypobaric hypoxia.

Effect of ischemia and ischemia--reperfusion on ryanodine binding and Ca2+ uptake of cardiac sarcoplasmic reticulum

The effect of 15 min of global, normothermic ischemia on 3H-ryanodine binding and the oxalate-supported Ca2+ uptake of cardiac sarcoplasmic reticulum (SR) was investigated in parallel using ventricular homogenates of isolated perfused rat hearts. Ischemia increased the Ca2+ efflux under the uptake assay conditions, as demonstrated by the greater stimulation of Ca2+ uptake by high concentrations of ryanodine (+RY) to close the SR Ca2+ channel. This effect was partially reversed by reperfusion. Ischemia depressed Ca2+ uptake rate -RY at free [Ca2+] of 0.4 microM and above, while the depression + RY was significant only above 10 microM Ca2+. We tested the hypothesis that inhibition of the Ca-ATPase alone, by adding thapsigargin or cyclopiazonic acid, could reproduce the effects of ischemia on the homogenate Ca2+ uptake rate. Thapsigargin or cyclopiazonic acid proportionally depressed Ca2+ uptake rate +RY and -RY and produced distinctly different effects of ischemia. Ischemia did not change the Bmax or Kd for equilibrium 3H-ryanodine binding, or the Hill coefficient or KCa for the [Ca2+]-dependence of equilibrium 3H-ryanodine binding. The rate of ryanodine binding, measured under the uptake conditions, was increased by ischemia and further increased by reperfusion. The effect of ischemia on the rate and extent of equilibrium binding to the high-affinity ryanodine binding site were unrelated to the highly reproducible effects on SR Ca2+ uptake rates measured in the homogenate.

[Tricuspid valve re-replacement: analysis of 4 cases]

The patients underwent tricuspid valve replacement may occur the mechanical valve failure caused by thrombosis and so on. It is necessary to reoperate urgently otherwise the patients will die. Four patients with this complications were treated successfully with tricuspid valve re-replacement at Fuwai Hospital in Beijing, China since 1989. The experience of management, the technique of tricuspid valve re-replacement and the choice of the valves were discussed.

[Management of nocturnal nasal mask continuous positive airway pressure in central hypoventilation in patients with respiratory diseases]

The effect of nasal mask CPAP administered during night in four central hypoventilation patients with various causes were investigated. On the basis of their histories, specific clinical manifestations, cranial CT and MRI, cerebral angiography and polysomnography. The patients (three males and one female) are diagnosed as primary alveolar hypoventilation and central hypoventilation, the later mainly caused by the compression of bulbar respiratory centre due to congenital deformity of right vertebral artery and deformity of foramen magnum. In order to assess the severity of nocturnal hypoventilation and blood oxygen level of the patients, polysomnography was taken before treatment, during 2L/min of oxygen via nasal tube and CPAP ventilation. Only oxygen administration did not ameliorate hypoventilation episodes and hypoxemia, lowest SaO2 is less than 50% on four patients, hypoventilation index is greater than 20 times/hour in three patients and 6.4 in a patient. Applying CPAP with the pressure fixed to 6-12 cm H2O can significantly improve hypoventilation index and hypoxemia with lowest SaO2 more than 70% (P < 0.001) and hypoventilation index less than 7 (P < 0.01). We conclude that nocturnal nasal mask CPAP is an effective treatment for central hypoventilation.

[Surgical correction of mitral valve prolapse]

Thirty-five patients with mitral valve prolapse were repaired at Fu Wai Hospital in Beijing between Jan. 1988 and June, 1993. 20 males and 15 females of them aged ranging from 7 to 52 years. 9 patients was less than 14 years old in this group. The mitral prolapse were caused by degeneration, congenital heart disease, trauma and rheumatic heart disease. The mitral anterior leaflet were eroded in 7 patients, posterior leaflet in 26 patients, both anterior and posterior leaflets in 2 patients. The dilation of the mitral annulus, rupture and prolongation of chordae and defect in the leaflets were found in these patients. The reconstruction of mitral valve were performed in all patients under cardiopulmonary bypass using the resection or plication of the prolapse parts of the leaflets or reduce the diameter of mitral annulus with a carpentier ring. The results were satisfactory without mortality in hospital or in following-up period. The indication and method of the operation were discussed.

Identification of a nonsense mutation at amino acid 584-arginine of platelet glycoprotein IIb in patients with type I Glanzmann thrombasthenia

Using Southern blot, the restriction digests of genomic DNAs in 11 patients with Glanzmann thrombasthenia from 10 unrelated kindreds were probed with a full-length GPIIb cDNA. An additional 2.3 kb Taq I fragment and two 1.65 kb and 0.65 kb fragments with reduced band intensity were found in the genes of two affected siblings from a family originating from the city of Huang Yan in the Zhejiang province. The Taq I digest of the abnormal gene was further probed with three portions of GPIIb cDNA, revealing that the heterozygous mutation was present in the region around exons 15-17 of the GPIIb gene. Two primers for polymerase chain reaction (PCR) were then designed, and a 394 bp PCR product was generated and sequenced, indicating that a stop codon (TGA) was substituted for an Arg codon (CGA) at amino acid position 584 of GPIIb, and resulted in a premature termination of translation and production of a shortened protein. The Western blot analysis showed that GPIIIa at the platelet surface was apparently deficient, it may be ascribed to the rapid turn-over of GPIIIa uncomplexed with the truncated GPIIb. The abnormal 2.3 kb Taq I fragment was used as a specific genetic marker to detect the carrier status of the patient family. The abnormal allele was proved to be derived from the mother, the two affected siblings are double heterozygotes, and one clinically unaffected daughter has also inherited this defective allele, while the father carries another recessive abnormal allele unidentified.

The effect of ruthenium red during Ca2+ depletion and repletion in the isolated perfused rat liver

Perfusion of rat liver with Ca(2+)-depleted buffer induces oxidative stress and liver damage, which can be prevented by Ca2+ repletion (Okuda et al. J Lab Clin Med). In the present study, we investigated the action of ruthenium red on acute Ca2+ loading after Ca2+ depletion in the isolated perfused rat liver. The major findings of this study are that 1) Ca2+ depletion-induced liver damage was related to mitochondrial disfunction; 2) ruthenium red inhibited the oxidative stress and liver damage normally seen during Ca2+ depletion; 3) ruthenium red inhibited the Ca2+ depletion-induced mitochondrial disfunction. These observations suggest that mitochondrial Ca2+ cycling is responsible for Ca2+ depletion-induced oxidative stress and liver damage.

[Corrective surgery for tetralogy of Fallot. Analysis of 156 cases]

156 consecutive patients with tetralogy of Fallot underwent corrective surgery between Sept. 1987 and Mar. 1991 at Fuwai hospital in Beijing. The patients consisted of 96 males and 60 females. Their age ranged from 3 to 32 years (average 12 +/- 6 years). 141 patients (91%) had cyanosis at rest and 135 patients had clubbed fingers and toes. Hemoglobin level ranged from 130 to 265 g/L (average 192 +/- 38 g/L), and more than 18 g/L in 84 patients. All the patients were confirmed by UCG and ventricular cinecardiogram. The operation was performed under CPB and hypothermia. Typical pathological changes were found in all the patients. Severe hypoplasia of infundibular and pulmonary trunk or stenosis at pulmonary annulus valves was noted in 60 patients, absence of pulmonary valve syndrome in 2, absence of left pulmonary artery in 2, abnormality of coronary artery in 3, pulmonary atresia in 1, ASD in 15, and foramen ovale in 23. All the patients recovered uneventfully except one who died from acute renal failure in the fifth day after operation. The criteria for size were suggested for the reconstruction of the right ventricular outflow tract and pulmonary trunk.

[Clinical use of polysomnography (PSG)]

The clinical diagnoses in 695 cases using PSG were analysed. The results are as follows: Obstructive sleep apnea syndrome (OSAS) in 482 cases (69.4%), chronic obstructive pulmonary diseases with nocturnal hypoxemia in 25 cases (3.6%), epilepsy in 31 cases (4.5%), other sleep disorders in 5 cases (0.7%), and essentially normal in 152 cases (21.9%). Some parameters of PSG in 65 cases with OSAS and those in 2 cases before and after treatment were analysed. It is emphasized that PSG is using for diagnosis of different types of OSAS with appraisable seriousness and of other related sleep disorders. The method and indications of PSG were discussed.

Single amino acid substitutions dissociate fibrinogen-clotting and thrombomodulin-binding activities of human thrombin

Thrombin is a serine protease that acts as a procoagulant by clotting fibrinogen and activating platelets and as an anticoagulant by activating protein C in a thrombomodulin-dependent reaction. Fibrinogen and thrombomodulin bind competitively to an anion-binding exosite on thrombin. We prepared recombinant normal human thrombin and mutant thrombins with single amino acid substitutions in order to localize and distinguish the fibrinogen- and thrombomodulin-binding sites. Normal and mutant thrombins had similar amidolytic activity. Thrombin K52E had approximately 2.5-fold increased protein C-activating activity but only approximately 17% of normal fibrinogen-clotting activity. Thrombin R70E had normal fibrinogen-clotting activity but only approximately 7% of normal protein C-activating activity. Thrombin R68E had markedly reduced activity in both assays. Decreased activation of protein C correlated with decreased binding affinity for thrombomodulin, and ability to activate platelets correlated directly with fibrinogen-clotting activity. These results demonstrate that thrombins with predominantly anticoagulant or procoagulant activity can be created by mutagenesis and that thrombomodulin- and fibrinogen-binding sites on thrombin may overlap but are not identical.

[Clinical study of fifty cases of Klinefelter's syndrome]

The authors report the clinical manifestations of 50 cases of Klinefelter's Syndrome proven by chromosome studies. The number of cases with the genotype of 47 XXY, 46 XY/47 XXY, 46 XX/47 XXY and 48 XXXY were 42, 6, 1 and 1 respectively. The chief complaint of 68% of the patients was maldevelopment of sex and that of 26% was gynecomastia. One fourth of the patients was born when their mothers' age already exceeded 35. About 1/5 had low intelligence. Secondary sexual characteristics were absent in all the patients. About 2/5 had gynecomastia. The average testicular volume was 4.0-1.3 ml, but no sperm was found in their semen. Their serum testosterone concentration decreased to 5.4 +/- 5.3 mM/L, but the serum TeBG, FSH and LH levels were significantly increased to 66.8 +/- 22.0 nM/L, 24.7 +/- 7.1 IU/L and 12.3 +/- 7.3 IU/L.

[Effect of testosterone preparations on the function of the hypothalamic pituitary axis in Klinefelter's syndrome]

This article prospectively observed the suppressive effects of the testosterone preparations on the elevated gonadotropin levels in Klinefelter's syndrome (KS). After sublingual administration of methyl testosterone 5 mg Bid, the serum T levels increased 97 and 126 ng/ml respectively in 6 normal men and 9 patients of KS and the serum FSH and LH levels did not changed significantly. After intramuscular injection of testosterone propionate 25 mg 3/week testovirone 100 mg 1/10 days and testosterone enanthate 200 mg/20 days, the serum T levels increased significantly both in 6 normal mon and 17 patients with KS. It took about 1 month for the LH levels to decrease to normal range and 3-6 months for the FSH levels to become normal. Our result indicates that it is necessary to treat the KS patients for long period to normalize the increased hypothalamic pituitary function.

Expression of von Willebrand factor in porcine vessels: heterogeneity at the level of von Willebrand factor mRNA

The expression of the von Willebrand factor (vWF) gene by cultured endothelial cells from the porcine pulmonary artery, aorta, and lung was compared at the levels of messenger (m)RNA and antigen. Steady-state levels of vWF mRNA were determined by dot-blot analysis using a partial human vWF cDNA as the hybridization probe; vWF mRNA from cultured aortic endothelial cells, and vWF antigen secreted into the culture supernatants were barely detectable. In contrast, vWF mRNA and antigen from the pulmonary artery endothelial cells were approximately eight to nine times that demonstrated by aortic cells. Levels of vWF mRNA and antigen in cultured lung cells were intermediate of those found in the pulmonary artery and aorta and correlated with the estimated number of cells demonstrated to be of endothelial origin in the mixed cell populations grown from the lung. Differences between the levels of vWF mRNA found in cultured cells from the pulmonary artery and those found in the aorta were maintained in cells processed directly from these vessels. Correlation between the levels of vWF mRNA and antigen in endothelial cells from different vessels of the pig suggests that the differential control of vWF synthesis is at the level of transcription. Furthermore, maintenance in cultured cells of the difference in transcription rates that were observed in vivo suggests that vWF gene expression is not exclusively regulated through environmental factors.

Analysis of von Willebrand factor mRNA from the lung of pigs with severe von Willebrand disease by using a human cDNA probe

To examine the control of porcine von Willebrand factor (vWF) biosynthesis we cloned human vWF complementary DNA (cDNA) and investigated the expression of the vWF gene in lungs from normal pigs and pigs with severe von Willebrand's disease (vWD). Recombinant clones spanning approximately 90% of human vWF cDNA were identified in a lambda gt10 human lung cDNA library by screening with oligonucleotides. One clone spanning nucleotides 960 to 3,240 of human vWF cDNA was used to investigate the steady-state levels of vWF mRNA in lungs from normal pigs and from pigs phenotypically determined to be homozygous for vWD. This clone hybridized with genomic DNA from pig leukocytes when Southern blots were processed under very stringent conditions; therefore, human cDNA clones were considered valid probes to detect porcine mRNA. Northern blot analysis of total RNA from normal pig lung and human umbilical vein endothelial cells identified the vWF mRNA as a molecular species of approximately 9.0 kilobases (kb). A very faint to undetectable band at 9.0 kb in total RNA from lungs of vWD pigs suggested a decreased rate of transcription of the vWF gene. Sucrose density gradient centrifugation of RNA from the vWD pigs confirmed by Northern analysis that the high-molecular weight fractions contained vWF mRNA and at the same size as normal pig mRNA. Dot blot hybridization analysis of vWF and actin mRNA processed under stringent conditions demonstrated that the relative ratio of vWF mRNA to actin mRNA in the vWD pigs varied from 21% to 41% of the ratio observed in normal pigs. Because the amount of vWF mRNA is not correlated to the amount of vWF activity or antigen in plasma of vWD pigs we conclude that posttranscriptional events are also probably involved in abnormal expression of vWF in these animals.

A simple and efficient method for isolating high molecular weight DNA from mammalian sperm

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