Essential contribution of caspase 3/CPP32 to apoptosis and its associated nuclear changes

Caspases are fundamental components of the mammalian apoptotic machinery, but the precise contribution of individual caspases is controversial. CPP32 (caspase 3) is a prototypical caspase that becomes activated during apoptosis. In this study, we took a comprehensive approach to examining the role of CPP32 in apoptosis using mice, embryonic stem (ES) cells, and mouse embryonic fibroblasts (MEFs) deficient for CPP32. CPP32^ex3−/− mice have reduced viability and, consistent with an earlier report, display defective neuronal apoptosis and neurological defects. Inactivation of CPP32 dramatically reduces apoptosis in diverse settings, including activation-induced cell death (AICD) of peripheral T cells, as well as chemotherapy-induced apoptosis of oncogenically transformed CPP32^−/− MEFs. As well, the requirement for CPP32 can be remarkably stimulus-dependent: In ES cells, CPP32 is necessary for efficient apoptosis following UV- but not γ-irradiation. Conversely, the same stimulus can show a tissue-specific dependence on CPP32: Hence, TNFα treatment induces normal levels of apoptosis in CPP32 deficient thymocytes, but defective apoptosis in oncogenically transformed MEFs. Finally, in some settings, CPP32 is required for certain apoptotic events but not others: Select CPP32^ex3−/− cell types undergoing cell death are incapable of chromatin condensation and DNA degradation, but display other hallmarks of apoptosis. Together, these results indicate that CPP32 is an essential component in apoptotic events that is remarkably system- and stimulus-dependent. Consequently, drugs that inhibit CPP32 may preferentially disrupt specific forms of cell death.     

Paediatric in-patient prescribing errors in Malaysia: a cross-sectional multicentre study

Background There is a lack of large comprehensive studies in developing countries on paediatric in-patient prescribing errors in different settings. Objectives To determine the characteristics of in-patient prescribing errors among paediatric patients. Setting General paediatric wards, neonatal intensive care units and paediatric intensive care units in government hospitals in Malaysia. Methods This is a cross-sectional multicentre study involving 17 participating hospitals. Drug charts were reviewed in each ward to identify the prescribing errors. All prescribing errors identified were further assessed for their potential clinical consequences, likely causes and contributing factors. Main outcome measures Incidence, types, potential clinical consequences, causes and contributing factors of the prescribing errors. Results The overall prescribing error rate was 9.2% out of 17,889 prescribed medications. There was no significant difference in the prescribing error rates between different types of hospitals or wards. The use of electronic prescribing had a higher prescribing error rate than manual prescribing (16.9 vs 8.2%, p < 0.05). Twenty eight (1.7%) prescribing errors were deemed to have serious potential clinical consequences and 2 (0.1%) were judged to be potentially fatal. Most of the errors were attributed to human factors, i.e. performance or knowledge deficit. The most common contributing factors were due to lack of supervision or of knowledge. Conclusions Although electronic prescribing may potentially improve safety, it may conversely cause prescribing errors due to suboptimal interfaces and cumbersome work processes. Junior doctors need specific training in paediatric prescribing and close supervision to reduce prescribing errors in paediatric in-patients.     

Evening primrose oil and treatment of premenstrual syndrome

The therapeutic effectiveness of evening primrose oil (Efamol, Vita-Glow) in the relief of 10 symptoms associated with premenstrual syndrome (PMS) as well as menstrual symptoms was studied in 38 women. The prospective trial was randomised, double-blind and placebo-controlled and was crossed-over after three cycles. Although the results showed an improvement in symptoms of PMS during the trial, no significant differences in the scoring between the active and placebo groups were found over six cycles. No "carry-over" effect of active medication was observed; the beneficial effect on all symptoms (psychological, fluid retention, breast) was rapid, the scores decreasing in the first cycle but increasing slightly at the change-over period after the third cycle, irrespective of whether the active or placebo medication was next given. These findings indicate that the improvement experienced by these women with moderate PMS was solely a placebo effect.     

胎儿和新生儿同种异体免疫性血小板减少症:进展与持续性争议

胎儿和新生儿同种异体免疫性血小板减少症(AIT)是引起胎儿和新生儿严重血小板减少的最常见原因.母亲针对源自父亲的胎儿血小板抗原的IgG抗体,在妊娠早期就可通过胎盘,通常导致胎儿严重血小板减少.由于一些血小板减少症临界值(50、100或150×109/L)的不同,他们的发生率亦各不相同.但在多数未经选择的人群中,AIT影响1/1 000到1/2 000活产数.在新生儿病房,临床确诊的重症AIT很罕见,可能只有1:10 000分娩数.     

Gated cardiac MR imaging and P-31 MR spectroscopy in humans at 1.5 T. Work in progress

The authors describe a technique to acquire gated cardiac proton magnetic resonance images and localized hydrogen-1 and phosphorus-31 spectra with a doubly tuned surface coil probe. The probe reduces study time because the need to exchange imaging and spectroscopy coils is eliminated, while at the same time the sensitivity of singly tuned coils is retained. In addition, the probe enhances the ability of the investigator to localize cardiac spectra spatially and temporally during the cardiac cycle. Spectra were acquired from the left ventricular myocardium in five volunteers, and systolic and diastolic gated P-31 spectra were shown.     

小鼠胚胎中脑区神经干细胞体外分离培养的特征

目的:在已成功分离培养皮质神经干细胞的基础上,体外分离培养鼠胚中脑区的神经干细胞,并进行鉴定,为中脑神经干细胞的基础与应用研究建立细胞培养平台。方法:实验于2005-11/2006-07在武汉工业学院完成。①选取孕12～13d昆明小鼠1只,处死后无菌条件下分离胚胎腹侧中脑,胰酶消化和机械吹打制成单细胞悬液,在碱性成纤维生长因子和B27存在的无血清培养基中培养扩增,机械分离法传代,观察细胞生长状况。②将传至第2代的神经球以20～30个/cm2接种于置有预先经左旋多聚赖氨酸包被盖玻片的24孔培养板中,加入含体积分数为0.1胎牛血清的DMEM/F12(不加任何生长因子)诱导分化。③采用免疫细胞化学染色方法鉴定神经干细胞及其传代细胞的分化方向。结果:①孕12～13d的鼠胚中脑细胞体外培养36h后,可见2～5个细胞的团块;48h后有明显球状团块产生,胞间界限不很清楚,出现神经细胞球;培养6d后传代,少部分单细胞于传代2d后出现分裂相,随后渐形成细胞团及神经球,生长性状基本同原代。②将培养的神经细胞球转入有血清培养时,约1周球体可完全分化为神经细胞和胶质细胞。免疫荧光染色显示神经球细胞表达巢蛋白,且神经元特异性烯醇化酶染色和胶质纤维酸性蛋白染色均呈阳性。结论:孕12～13d鼠胚胎腹侧中脑区存在神经干细胞,这些细胞在B27和碱性成纤维生长因子存在的无血清培养基中能够成功的在体外培养和传代。     

Expression of haem oxygenase in cirrhotic rat liver

The haem oxygenase (HO)/carbon monoxide (CO) system has been implicated as a modulator of hepatobiliary function. This study investigated HO expression in the process of cirrhosis development, as well as its relationship to nitric oxide synthase (NOS). Liver cirrhosis was induced in rats by chronic bile duct ligation (BDL). HO mRNA expression was evaluated by competitive RT-PCR, while protein expression was determined by immunoblotting and immunohistochemistry. In liver tissue where cirrhosis had fully developed, the expression levels of HO-1 were greatly enhanced at both mRNA and protein level compared with sham livers. Immunohistochemistry showed that HO-1 was induced in hepatocytes and enhanced in some of the Kupffer-like cells in BDL livers. In contrast, there was no difference between the sham and the BDL livers for the expression levels of HO-2. Interestingly, administration of the NOS inhibitor aminoguanidine (AG) or N(G)-nitro-L-arginine methyl ester inhibited HO-1 expression. To study further the role of HO-1 in the development of liver cirrhosis, hepatocytes were isolated from the rats at different time points after BDL operation. HO-1 was expressed in hepatocytes at high levels during the early onset of cirrhosis but dropped slightly at a later stage of cirrhosis. Zinc protoporphyrin IX (ZnPP), an HO inhibitor, blocked HO-1 expression in hepatocytes from BDL cirrhotic rats, but enhanced the activity of inducible NOS (iNOS) in BDL hepatocytes. In conclusion, HO-1 was induced in the hepatocytes of rats undergoing cirrhosis, suggesting that HO-1 plays a role in the development of liver cirrhosis. Induction of HO-1 may be mediated partially by iNOS. However, once it is induced, HO-1 may be important in modulating iNOS activity, thus playing a protective role in liver cirrhosis.     

Detection of submicroscopic constitutional chromosome aberrations in clinical diagnostics: a validation of the practical performance of different array platforms

For several decades etiological diagnosis of patients with idiopathic mental retardation (MR) and multiple congenital anomalies (MCA) has relied on chromosome analysis by karyotyping. Conventional karyotyping allows a genome-wide detection of chromosomal abnormalities but has a limited resolution. Recently, array-based comparative genomic hybridization (array CGH) technologies have been developed to evaluate DNA copy-number alterations across the whole-genome at a much higher resolution. It has proven to be an effective tool for detection of submicroscopic chromosome abnormalities causing congenital disorders and has recently been adopted for clinical applications. Here, we investigated four high-density array platforms with a theoretical resolution < or =100 kb: 33K tiling path BAC array, 500K Affymetrix SNP array, 385K NimbleGen oligonucleotide array and 244K Agilent oligonucleotide array for their robustness and implementation in our diagnostic setting. We evaluated the practical performance based on the detection of 10 previously characterized abnormalities whose size ranged from 100 kb to 3 Mb. Furthermore, array data analysis was performed using four computer programs developed for each corresponding platform to test their effective ability of reliable copy-number detection and their user-friendliness. All tested platforms provided sensitive performances, but our experience showed that accurate and user-friendly computer programs are of crucial importance for reliable copy-number detection.     

Neonatal mortality in a referral hospital in Cameroon over a seven year period: trends,associated factors and causes

Background

The fourth Millennium Development Goals targets reduction of the mortality rate of under-fives by 2/3 by the year 2015. This reduction starts with that of neonatal mortality representing 40% of childhood mortality. In Cameroon neonatal mortality was 31% in 2011.

Objectives

We assessed the trends, associated factors and causes of neonatal deaths at the Yaounde Gynaeco-Obstetric and Pediatric Hospital.

Methods

The study was a retrospective chart review. Data was collected from the hospital records, and included both maternal and neonatal variables from 1^st January 2004 to 31^st December 2010.

Results

The neonatal mortality was 10%. Out-borns represented 49.3% of the deceased neonates with 11.3% born at home. The neonatal mortality rate followed a downward trend dropping from 12.4% in 2004 to 7.2% in 2010. The major causes of deaths were: neonatal sepsis (37.85%), prematurity (31.26%), birth asphyxia (16%), and congenital malformations (10.54%). Most (74.2%) of the deaths occurred within the first week with 35% occurring within 24hours of life. Mortality was higher in neonates with birth weight less than 2500g and a gestational age of less than 37 weeks. In the mothers, it was high in single parenthood, primiparous and in housewives and students..

Conclusion

There has been a steady decline of neonatal mortality since 2004.Neonatal sepsis, prematurity, birth asphyxia and congenital malformations were the major causes of neonatal deaths. Neonatal sepsis remained constant although at lower rates over the study period.