休克期大面积切痂对严重烧伤大鼠细胞免疫功能影响的研究

目的 观察休克期大面积切痂对严重烧伤大鼠细胞免疫功能的影响，探索改善烧伤后机体免疫功能紊乱的有效方法。方法 将大鼠分成休克期切痂组（A组）、常规切痂组（B组）和正常对照组（C组）。A、B组造成30％TBSAⅢ度烫伤，C组不烫伤。A组伤后第6h、B组伤后第4d切痂，并于伤后第1、5、9d各活杀10只，取材送检，观察其免疫指标的变化。结果 （1）A、B组与C组比较：A、B组烫伤大鼠各时相点CD3^＋T细胞变化不大（P〉0．05），但CD4^＋T细胞、CD4^＋／CD8^＋比值明显下降、CD8^＋T细胞增高（P〈0．05或P〈0．01）。NK细胞活性明显下降（P〈0．05或P〈0.01），外周血CD25^＋T淋巴细胞表达及经活化后脾脏CD25^＋T淋巴细胞表达明显下降（P〈0．05或P〈0．01）。（2）A组与B组比较：A组CD4^＋T细胞、CD4^＋／CD8^＋比值明显升高、CD8^＋T细胞降低（P〈0．05或P〈0．01），NK细胞活性明显升高（P〈0．05或P〈0．01），外周血CD25^＋T淋巴细胞表达及经活化后脾脏CD25^＋T淋巴细胞表达均明显升高（P〈0．05或P〈0．01）。结论 （1）大鼠烫伤后细胞免疫状况发生了明显变化。（2）休克期切痂可以改善烫伤大鼠T淋巴细胞亚群分布，提高NK细胞活性，增加外周血CD25^＋T淋巴细胞的表达。提高经活化后脾脏CD25^＋T淋巴细胞数。从而改善烫伤大鼠伤后机体的细胞免疫功能。     

Mild atopic dermatitis lacks systemic inflammation and shows reduced nonlesional skin abnormalities

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Skeletal abnormalities in the Apert syndrome

This paper reports on skeletal abnormalities in 38 patients with Apert syndrome. Analysis includes alterations in the shoulders, humeri, elbows, hips, knees, rib cage, and spine (except the cervical spine). Some patients had subacromial dimples and elbow dimples during infancy. Mobility at the glenohumeral joint was limited. Progressive limitation in abduction, forward flexion, and external rotation with growth was virtually a constant finding. The acromioclavicular joint was prominent and sometimes had an angular, pointed appearance clinically. This was often associated with atrophic musculature and winging of the scapulae. Limited elbow mobility was common and usually mild in degree. Decreased elbow extension was most often found with decreased flexion, pronation, and supination occurring less frequently. Limited elbow mobility did not change significantly with growth in contrast to the increasing severity observed in the shoulder joint. Short humeri were a constant finding beyond infancy and genua valga of mild degree were present in many cases. Radiographic examination strongly suggests that the Apert syndrome is characterized by a multiple epiphyseal dysplasia. We found delay in appearance of postnatal ossification centers, particularly in the humeral head, greater tuberosity, capitulum, and radial head. Subsequently, these bones became abnormal in shape. Glenoid dysplasia was observed consistently. The neck of the scapula was very short or absent and the inferior margin of the glenoid cavity was poorly demarcated from the infraglenoid tubercle. The humeral head became oblong in shape with relative prominence of the greater tuberosity which compromised abduction. In the elbow, the capitulum was often small and the radial head was flat in many instances. Subluxation or dislocation of the radial head or angulation of the radial neck was observed in some cases. In the hip joint of some adults, the femoral necks were short and broad with prominence of the greater trochanters. Less common radiographic findings are also discussed. © 1993 Wiley-Liss, Inc.     

A multicentre randomized controlled trial of oral misoprostol and i.m. syntometrine in the management of the third stage of labour

Postpartum haemorrhage accounts for nearly 28% of maternal mortality in developing countries. Syntometrine is an effective and commonly used oxytocic in preventing postpartum haemorrhage, but it requires a controlled storage environment and i.m. administration. Misoprostol is an orally active uterotonic agent. A total of 2058 patients having a singleton pregnancy, low risk for postpartum haemorrhage and vaginal delivery were randomized to receive either 1 ml syntometrine or 600 microgram misoprostol for the management of the third stage of labour. There were no significant differences between the two groups in the mean blood loss, the incidence of postpartum haemorrhage and the fall in haemoglobin concentration. The need for additional oxytocic injection was significantly higher in the misoprostol group [relative risk (RR) 1.62, 95% confidence interval (CI) 1.34-1.96], but that of manual removal of placenta was reduced (RR 0.29, 95% CI 0.09-0.87). Shivering and transient pyrexia were more common in the misoprostol group. Oral misoprostol might be used in the management of the third stage, especially in situations where the use of syntometrine is contraindicated and facilities for storage and parenteral administration of oxytocics are limited.     

Fertilization and early embryology: The effect of equilibration temperature and time on the outcome of ultrarapid freezing of 1-cell mouse embryos

Mouse 1-cell embryos were frozen ultrarapidly at a rate of 2500°C/minin solutions containing 0.25 M sucrose, 0.5% (w/v) bovine serumalbumin (BSA) and 3 or 4.5 M dimethyl sulphoxide (DMSO) or 3or 4.5 M 1, 2-propanediol (PROH) in HEPES-buffered modifiedEarle's medium. We investigated the effect of pre-freeze equilibrationfor 1, 3, 5 or 10 min at 22°C and for 1, 3, 5, 10, 15 or20 min at 4°C. After thawing in a 22°C water bath ata rate of 2500°C/min and dilution in 1 M sucrose in HEPES-bufferedmodified Earle's medium, embryos were cultured in vitro in bicarbonate-bufferedmodified Earle‘s medium with 0.5% (w/v) crystalline BSA.Embryo viability was expressed as the percentage of hatchingor hatched blastocysts resulting from the initial number offrozen-thawed 1-cell embryos. To determine the toxicity of thefreezing solutions, embryo viability was evaluated after equilibrationwithout freezing. Our results demonstrated that the concentration,the equilibration temperature and time are very important factorsin ultrarapid freezing of mouse 1-cell embryos. Optimal viabilitywas found when equilibration was done in 4.5 M DMSO for 3–5min at 22°C and in 4.5 M PROH for 3–5 min at 4°C.The results with regard to exposure to the freezing solutionsindicated that the loss of viability beyond an optimum is notdue solely to cryoprotectant toxicity, in particular not at4°C and not for DMSO. It is suggested that the temperatureand time of equilibration influence the degree of cryoprotectantpermeation and subsequent rehydration, which play a role indetermining freezing susceptibility in terms of ice formation.We conclude that both DMSO and, in contradiction to previousreports, PROH can be used perfectly adequately for ultrarapidfreezing on condition that concentration, and the temperatureand time of equilibration are controlled.     

Paternal effects acting during the first cell cycle of human preimplantation development after ICSI.

BACKGROUND: The ability of human embryos to undergo normal development has been shown previously to be subject to strong paternal (sperm-derived) effects. This study was undertaken to determine whether paternal influences on human embryo quality are detectable as early as the first cell cycle after fertilization. METHODS: The quality of zygotes and cleaving embryos resulting from sibling donor oocytes fertilized by sperm from different patients were compared in a donor oocyte-sharing programme. RESULTS: Fertilizations with sperm from certain individuals repeatedly resulted in the formation of high proportions of zygotes with abnormal pronuclear morphology that subsequently tended to cleave slowly and to show extensive fragmentation and blastomere irregularities. This phenomenon was observed with oocytes from two different donors for each of these individuals and contrasted with normal developmental performance of embryos resulting from sibling oocytes fertilized by sperm from other men with similar basic sperm characteristics. Fertilization rates were not related to these differences. CONCLUSIONS: These data point to a very early onset of paternal effects that condition human embryo development. These effects may be both of genetic (related to the minor gene activity of the male pronucleus) or epigenetic (related to the sperm-derived oocyte-activating factor or sperm centrosome) origin.     

Laser-assisted zona pellucida thinning prior to routine ICSI

BACKGROUND: In MII oocytes showing difficult oolemma breakage, ICSI can cause an increase in the degeneration rate. This may be overcome by laser-assisted ICSI using a 5-10 micro m opening in the zona pellucida for injection. However, such a small opening might impair the hatching process, especially if assisted hatching is applied in addition. In order to prevent this, the present study used routine injection through an area of zona pellucida in which laser zona thinning had been applied, providing for both a reduced mechanical stress to the oocyte and assisted hatching. METHODS: This prospective study involved 100 cycles with 1016 MII oocytes. Conventional ICSI (control group) was compared with a modified laser-assisted ICSI (study group) in sibling oocytes. In the latter group oocytes were injected through an extended area of zona thinning. RESULTS: Degeneration rate was significantly lower in the study group (P < 0.004). There were no differences in fertilization, or formation and quality of blastocysts. In the study group embryo quality on day 2 was significantly better (P = 0.004) and herniation of day 5 blastocysts was increased (P = 0.005). Rates of implantation and pregnancy were not affected. However, on day 3 laser-assisted ICSI proved beneficial (P = 0.038) in terms of clinical pregnancy rate. CONCLUSIONS: The new method combines a less invasive ICSI technique with assisted hatching. Our preliminary data indicate that in addition to an improved oocyte survival, this new approach increases the hatching rate in vitro, which may explain the increase in pregnancy rate, at least in day 3 transfers.     

Pregnancies following blastocyst stage transfer in PGD cycles at risk for beta-thalassaemic haemoglobinopathies.

BACKGROUND: Preimplantation genetic diagnosis (PGD) usually involves blastomere biopsy 3 days post-insemination (p.i.), followed by genetic analysis and transfer of unaffected embryos later on day 3 or 4. We evaluate a strategy involving embryo biopsy on day 3 p.i., genetic analysis on day 4 and, following culture in blastocyst sequential media, transfer of unaffected embryos on day 5 p.i. METHODS: PGD cycles were initiated in 15 couples at risk of transmitting beta-thalassaemia major. Oocyte retrieval and ICSI were performed according to standard protocols. Embryo culture used blastocyst sequential media. Embryos were biopsied on day 3 p.i. using acid Tyrode's for zona drilling, and the single blastomeres were genotyped by a protocol involving nested polymerase chain reaction and denaturing gradient gel electrophoresis analysis. RESULTS: Forty of 109 (37%) embryos biopsied on day 3 p.i. developed to blastocysts by day 5 p.i., with at least one blastocyst available for transfer in 12 cycles (80%). Genotype analysis characterized 51/109 (47%) embryos unaffected for beta-thalassaemia major, of which 28 were blastocysts. Transfer of 37 day 5 p.i. embryos (blastocysts and non blastocysts) initiated eight clinical pregnancies. Implantation rate per embryo transferred was 12/37 (32%). CONCLUSIONS: Embryo biopsy on day 3, followed by delayed transfer until day 5 p.i. offers a novel and effective strategy to overcome the time limit encountered when performing PGD, without compromising embryo implantation.