Recovery of fatiguedXenopus muscle fibres is markedly affected by the extracellular tonicity

Summary In previous studies it has shown that isolatedXenopus muscle fibres may enter a long-lasting, reversible state of severely depressed tetanic force when recovering from fatigue produced by repeated tetani. The mechanism behind this postcontractile depression (PCD) has been studied further by exposing rested and fatigued fibres to a hypertonic (1.2 x normal tonicity) or a hypotonic (0.8x) solution. In the rested state the average tetanic tension increased by 9% in the hypotonic solution and was reduced by 8% in the hypertonic solution. After fatiguing stimulation similar alterations of tonicity resulted in changes of tetanic tension of about 40% in easily fatigable fibres (type 1;n=21); an increased tonicity always resulted in reduced tension, whereas decreased tonicity gave an increased tension output. Similar results were obtained in fatigue-resistant fibres (type 2;n=4), but here the force depression caused by hypertonicity appeared to be irreversible. Thus, fibres were markedly more sensitive to changes of the extracellular tonicity during the recovery period. It is suggested that this increased sensitivity reflects alterations in the signal transmission between t-tubules and sarcoplasmic reticulum.     

Plasma lactate accumulation is reduced during incremental exercise in untrained women compared with untrained men

The lactate threshold (LT) is commonly reported as not different between sexes, yet lower blood lactate concentrations have been reported in women during submaximal exercise. The purpose of the present study was to measure the changes in plasma lactate concentration [La(-1)] in men and women during incremental cycle ergometer exercise using the same protocol and compare the data using several different methods of analysis. A group of untrained men (n = 21) and women (n = 22) were studied and venous blood drawn at regular intervals during and after exercise for assay of plasma [La(-1)]. Plasma [La(-1)] increased during exercise in both sexes, reaching higher values in men, both at exhaustion (men 8.6 +/- 2.3 mmol l(-1); women 6.2 +/- 2.3 mmol l(-1); P = 0.01) and post-exercise (men 11.8 +/- 2.1 mmol l(-1); women 10.2 +/- 2.4 mmol l(-1); P = 0.03). Logarithmic transformation of the data yielded LT values that were not different between sexes (men 44.2 +/- 12.9; women 50.2 +/- 12.6; %VO2peak; P = 0.45), yet both the 2 and 4 mmol l(-1) fixed concentration LT occurred at lower relative intensities in men (2 mmol l(-1): men 50.9 +/- 12.9; women 66.9 +/- 11.1; %VO2peak; P = 0.01). 4 mmol l(-1): men 75.7 +/- 11.0; women 90.6 +/- 9.2; VO2peak; P = 0.01). However, when the plasma [La(-1)] was examined in both sexes throughout exercise, using a single exponential function, plasma [La(-1)] was significantly lower in women (P < 0.05) at all relative intensities between 30 and 100%VO2peak. While the basis of this sex difference is unknown, reduced plasma [La(-1)] during submaximal exercise in women may offset to some degree the endurance performance disadvantage of their lower VO2peak.     

Status of zinc and copper in pregnant women and their changes during preeclampsia

In order to evaluate the status of zinc and copper in pregnant women and in preeclampsia, we conducted a prospective case-control study. It involved 56 pregnant women compared with 30 non-pregnant women selected as controls. For pregnant women, serum levels of zinc, copper and ceruloplasmin were determined quarterly. These same measurements were performed once in controls. The comparison of various parameters in normal pregnancy and in control women revealed a statistically significant decrease in serum levels of zinc from 1st to 3rd quarter. The serum levels of copper were normal both in controls and in parturients. However, a significant increase of copper levels from 1st to 3rd quarter of pregnancy was found. The serum levels of ceruloplasmin appear to be invariable during pregnancy. Moreover, we noted a disturbance of these parameters in preeclampsia (hypozincemia, hypocupremia and a significant increase of ceruloplasmin). Zinc and copper are essential for the development and fetal growth. Their involvement in several maternal-fetal complications is not currently in any doubt.     

Predictive factors for preeclampsia in pregnant women: a Receiver Operation Character approach

Introduction

Preeclampsia is a major cause of maternal and prenatal mortality and morbidity worldwide. There are some risk factors that are of great value for prediction of preeclampsia by which the practitioners can counsel women regarding this disease. The aim of this study was to analyze the role of such risk factors as the predictors associated with preeclampsia among Iranian women using logistic regression.

Material and methods

The role of some risk factors such as demographic, anthropometric, medical and obstetrics variables in preeclampsia among 610 women attending the obstetric ward of Mustafa hospital in Ilam in the west of Iran was analyzed from May to September 2010. All the pregnant women referred to this hospital participated in the study except those cases that had abortion. Unvaried and Multiple logistic regression analyses were used to find the predictive factors behind preeclampsia. Standard errors of area compute using nonparametric methods. A p-value of 0.05 was considered statistically significant.

Results

Prevalence of preeclampsia was 9.5% (95% CI 7.4–11.6%). Predictive model build using history of preeclampsia, history of hypertension, and history of infertility. Area Under the Receiver Operation Character (AUROC) was estimated 0.67 (95% CI 0.59–0.67, p < 0.01) that showed that using the model is much better than having a guess.

Conclusions

The odd of preeclampsia increased in women with a history of preeclampsia, hypertension and infertility. Recognition of these predictor factors would improve the ability to diagnose and monitor women likely to develop preeclampsia before the onset of disease for timely interventions.     

抵抗素蛋白在妊娠糖尿病孕妇与正常孕妇胎盘的表达

目的了解抵抗素蛋白在妊娠糖尿病孕妇与正常孕妇胎盘的表达情况,探讨抵抗素与妊娠生理性胰岛素抵抗(insu lin resistance,IR)及妊娠糖尿病(gestational d iabetes m ellitus,GDM)的关系。方法W estern b lot法检测妊娠糖尿病孕妇与正常孕妇胎盘抵抗素蛋白表达情况;葡萄糖氧化酶法测定血糖,测量收缩压(SBP)及舒张压(DBP)。结果W estern b lot结果以OD值表示,GDM孕妇胎盘抵抗素蛋白的表达(79305±7645.12)显著高于正常孕妇胎盘的表达(50718±3818.20)(P<0.01)。结论妊娠糖尿病孕妇胎盘抵抗素蛋白的表达显著高于正常孕妇胎盘的抵抗素蛋白的表达;表明胎盘可分泌抵抗素;抵抗素是引起妊娠生理性胰岛素抵抗和妊娠糖尿病的一个细胞因子。     

硬脊膜穿破硬膜外阻滞在子痫前期孕妇剖宫产术中的应用效果观察

目的:探讨硬脊膜穿破硬膜外（DPE）阻滞在子痫前期孕妇剖宫产术中的应用效果。方法:前瞻性随机对照研究。纳入2019年3月—2021年3月安徽省妇幼保健院择期行剖宫产术的子痫前期孕妇90例,年龄21～38（27.4±3.8）岁,孕周36～41（38.2±1.3）周,孕次1～4（1.7±0.9）次,均为单胎且首次行剖宫产术...     

Neutrophil survival is markedly reduced by incubation with influenza virus and Streptococcus pneumoniae: role of respiratory burst

Bacterial superinfections are an important cause of morbidity and mortality during influenza A virus (IAV) epidemics. We demonstrate that incubation with the combination of IAV and Streptococcus pneumoniae caused marked reductions in survival of neutrophils in vitro compared with treatment with control buffer or IAV or S. pneumoniae alone. This cooperative effect was in part mediated by acceleration of neutrophil apoptosis as evidenced by increases in annexin-V binding and caspase-3 activation. However, GM-CSF did not increase survival of neutrophils exposed to IAV and S. pneumoniae. IAV enhanced neutrophil uptake of S. pneumoniae significantly. Furthermore, the combination of IAV and S. pneumoniae caused significantly more hydrogen peroxide production than IAV or S. pneumoniae alone. This increased respiratory burst activity contributed to the diminished neutrophil survival caused by IAV and S. pneumoniae. The NADPH oxidase inhibitor, diphenyleneiodonium, significantly improved survival of neutrophils treated with IAV and S. pneumoniae. These findings may help to explain the increased susceptibility of IAV-infected patients to infections with S. pneumoniae.     

High levels of maternal serum IL-17 and activin A in pregnant women affected by systemic lupus erythematosus

Citation
Torricelli M, Bellisai F, Novembri R, Galeazzi LR, Iuliano A, Voltolini C, Spreafico A, Galeazzi M, Petraglia F. High levels of maternal serum IL‐17 and activin A in pregnant women affected by systemic lupus erythematosus. Am J Reprod Immunol 2011; 66: 84–89 Problem To evaluate changes of serum IL‐17, activin A, follistatin, and other cytokines during pregnancy in women with systemic lupus erythematosus (SLE). Method of study A group of patients with SLE and controls were longitudinally studied, collecting a blood sample before and during three trimesters of pregnancy. Serum activin A, follistatin, IL‐17, IL‐6, IL‐10, and TNF‐α concentrations were evaluated by specific ELISA. Results Before pregnancy, while serum IL‐17, IL‐6, IL‐10, and TNF‐α resulted significantly higher in women with SLE (P < 0.001), activin A and follistatin were not changed. Serum IL‐17 concentrations were higher in SLE than in controls with no changes during pregnancy. IL‐6 increased in both groups, resulting higher in SLE than in controls only in the first trimester (P < 0.05). IL‐10 concentration in SLE increased during pregnancy resulting significantly higher than in controls (P < 0.01). TNF‐α levels were higher in SLE than in controls in third trimester (P < 0.01). Serum activin A levels in SLE were significantly higher than in controls (P < 0.001) at third trimester. Conclusion Women with SLE show increased secretions of activin A, IL‐17, IL‐6, IL‐10, and TNF‐α during gestation, with a different trend for the various cytokines. These data suggest that patients with SLE have a hyper‐reactive immune system, probably receiving a placental contribution.     

Downregulation of CD163 in monocytes and its soluble form in the plasma is associated with a pro-inflammatory profile in pregnant women with preeclampsia

Immunologic Research - Preeclampsia (PE) is a pregnancy-specific syndrome characterized by a systemic inflammatory response that polarizes peripheral blood monocytes to the M1 phenotype. The...     

Escherichia coli bacteraemia in pregnant women is life-threatening for foetuses

In order to improve knowledge on Escherichia coli bacteraemia during pregnancy, we studied clinical data and performed molecular characterization of strains for 29 E. coli bacteraemia occurring in pregnant women. Bacteraemia mostly occurred in the third trimester of pregnancy (45%) and was community-acquired (79%). Portals of entry were urinary (55%) and genital (45%). E. coli strains belonged mainly to phylogroups B2 (72%) and D (17%). Four clonal lineages (i.e. sequence type complex (STc) 73, STc95, STc12 and STc69) represented 65% of the strains. The strains exhibited a high number of virulence factor coding genes (10 (3–16)). Six foetuses died (27%), five of them due to bacteraemia of genital origin (83%). Foetal deaths occurred despite adequate antibiotic regimens. Strains associated with foetal mortality had fewer virulence factors (8 (6–10)) than strains involved in no foetal mortality (11 (4–12)) (p 0.02). When comparing E. coli strains involved in bacteraemia with a urinary portal of entry in non-immunocompromised pregnant vs. non-immunocompromised non-pregnant women from the COLIBAFI study, there was no significant difference of phylogroups and virulence factor coding genes. These results show that E. coli bacteraemia in pregnant women involve few highly virulent clones but that severity, represented by foetal death, is mainly related to bacteraemia of genital origin.     

血清PAPP-A在正常孕妇及子痫前期患者中的研究

目的探讨正常孕妇各孕周血清妊娠相关蛋白A(PAPP-A)的变化,及其与子痫前期发病的关系.方法采用时间分辨荧光免疫分析技术(DELFIA)检测11w至足月孕妇3935例,统计分析子痫前期孕妇与正常孕妇外周血清PAPP-A的中位数的差异.结果在正常孕妇组,血清PAPP-A浓度值随着孕周的增加而不断增高,至孕晚期达到最高水平;而子痫前期组孕妇外周血清PAPP-A水平明显高于相应孕周正常孕妇组的中位数.结论正常孕妇血清PAPP-A浓度随妊娠进展而逐渐上升至足月;子痫前期患者血清PAPP-A浓度显著高于同孕周正常孕妇,PAPP-A与子痫前期发病存在相关关系.     

Plasmodium falciparum rosette formation is uncommon in isolates from pregnant women

We examined the formation of Plasmodium falciparum erythrocyte rosettes using parasite isolates from placental or peripheral blood of pregnant Malawian women and from peripheral blood of children. Five of 23 placental isolates, 23 of 38 maternal peripheral isolates, and 136 of 139 child peripheral isolates formed rosettes. Placental isolates formed fewer rosettes than maternal isolates (range, 0 to 7. 5% versus 0 to 33.5%; P = 0.002), and both formed fewer rosettes than isolates cultured from children (range, 0 to 56%; P < 0.0001). Rosette formation is common in infections of children but uncommon in pregnancy and rarely detected in placental isolates.     

妊高征胎盘、脐血管中TNF-α表达及组织病理变化的研究

目的研究妊高征患者胎盘和脐血管组织中肿瘤坏死因子(TNF-α)的表达及组织的病理变化情况.方法采用SABC法对轻、中、重度妊高征共27例和正常妊娠组10例的胎盘和脐血管组织进行TNF-α的免疫组化染色,观察各组TNF-α的定位、分布和表达量的差异.同时常规HE染色观察胎盘等形态学变化.结果各组均可见TNF的表达,其定位和分布无差异,主要见于合体滋养细胞、蜕膜细胞、血管内皮细胞和平滑肌细胞等.但中、重度妊高征组TNF的表达量较正常组显著升高(P<0.05,P<0.01).此外,中、重度妊高征组可见细胞滋养细胞增生,合体细胞结节、纤维素样坏死显著增多等病理变化,与正常组相比有显著性差异.结论妊高征时,胎盘、脐血管亦可能是TNF-α的重要产生释放部位.且TNF-α可能通过某些直接或间接的途径,参与了妊高征损伤和代偿并存的复杂变化,在妊高征的发生发展中起着重要作用.     

子痫前期胎盘、脐血管中神经激肽B表达及组织病理变化的研究

目的研究子痫前期患者胎盘、脐血管中神经激肽B（neurok in in B,NKB）的表达及组织的病理变化情况。方法采用SP法对轻、重度子痫前期组共40例和正常妊娠组20例的胎盘和脐血管组织进行NKB的免疫组化染色,观察各组NKB的定位、分布和表达量的差异。同时常规HE染色观察各组胎盘、脐血管的病理变化。结果NKB在各组胎盘合体滋养细胞、毛细血管内皮细胞、脐静脉内皮细胞中均有不同程度的表达。轻、重度子痫前期胎盘组织中,其NKB含量明显高于正常组（P〈0.05,P〈0.01）,HE染色可见子痫前期组细胞滋养细胞增生,合体细胞结节、纤维素样坏死显著增多等病理变化,与正常组相比有显著性差异。结论胎盘可能是NKB的重要产生释放部位。且NKB可能通过某些直接或间接的途径,参与了子痫前期损伤和代偿并存的复杂变化,在子痫前期的发生发展中起着重要作用。     

Plasma triglyceride concentrations are rapidly reduced following individual bouts of endurance exercise in women

It is known that chronic endurance training leads to improvements in the lipoprotein profile, but less is known about changes that occur during postexercise recovery acutely. We analyzed triglyceride (TG), cholesterol classes and apolipoproteins in samples collected before, during and after individual moderate- and hard-intensity exercise sessions in men and women that were isoenergetic between intensities. Young healthy men (n = 9) and young healthy women (n = 9) were studied under three different conditions with diet unchanged between trials: (1) before, during and 3 h after 90 min of exercise at 45% VO₂peak (E45); (2) before, during and 3 h after 60 min of exercise at 65% VO₂peak (E65), and (3) in a time-matched sedentary control trial (C). At baseline, high-density lipoprotein cholesterol (HDL-C) was higher in women than men (P < 0.05). In men and in women, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), HDL-C, apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), and LDL peak particle size were unaltered by exercise either during exertion or after 3 h of recovery. In women, but not in men, average plasma TG was significantly reduced below C at 3 h postexercise by approximately 15% in E45 and 25% in E65 (P < 0.05) with no significant difference between exercise intensities. In summary, plasma TG concentration rapidly declines following exercise in women, but not in men. These results demonstrate an important mechanism by which each individual exercise session may incrementally reduce the risk for cardiovascular disease (CVD) in women.     

NADPH-oxidase activity of stimulated neutrophils is markedly increased by serum

In this study we have investigated the effects of serum (10, 20, and 40% final concentrations) on the activity of NADPH-oxidase and energy metabolism of activated human neutrophils in vitro. Neutrophils were stimulated with FMLP, PMA, or opsonized zymosan in the presence and absence of serum, and generation of reactive oxidants by intact cells was measured using lucigenin-enhanced chemiluminescence (LECL). This method was also used to measure NADPH-oxidase activity in purified membrane preparations from neutrophils activated with PMA in the presence or absence of serum. Cellular ATP levels and activities of the various glycolytic enzymes were assayed using CL and spectrophotometric procedures, respectively. Inclusion of serum with neutrophils during exposure to the various stimuli of membrane-associated oxidative metabolism caused significant enhancement of the LECL responses of intact cells as well as of the activity of NADPH-oxidase in purified membranes prepared from PMA-activated neutrophils. In the absence of serum, the ATP levels and activity of glyceraldehyde-3-phosphate dehydrogenase (G3PDH), but not the other glycolytic enzymes, were decreased in activated neutrophils, while inclusion of serum preserved neutrophil ATP levels and activity of G3PDH. Serum supplementation of the cell-suspending medium appears to promote optimum activity of NADPH-oxidase in stimulated neutrophils by preventing premature, oxidative inactivation of cellular energy metabolism.