Chromosomal Mosaicism in Cleavage-Stage Human Embryos and the Accuracy of Single-Cell Genetic Analysis

Purpose: Our purpose was to assess the effect of chromosomal mosaicism in cleavage-stage human embryos on the accuracy of single-cell analysis for preimplantation genetic diagnosis. Methods: Multicolor fluorescence in situ hybridization with X, Y, and 7 or X, Y, 7, and 18 chromosome-specific probes was used to detect aneuploidy in cleavage-stage human embryos. Results: Most nuclei were diploid for the chromosomes tested but there was extensive mosaicism including monosomic, double-monosomic, nullisomic, chaotic, and haploid nuclei. Conclusions: Identification of sex by analysis of a single cleavage-stage nucleus is accurate but 7% of females are not identified. One or both parental chromosomes 7 were absent in at least 6.5% of the nuclei. With autosomal recessive conditions such as cystic fibrosis, carriers would be misdiagnosed as normal or affected. With autosomal dominant conditions, failure to analyze the affected parents allele (1.6–2.5%) would cause a serious misdiagnosis and analysis of at least two nuclei is necessary to reduce errors.     

Retinal function and histologic changes following intravitreal injection of indocyanine green in a rabbit model.

The aim of this animal study was to investigate the effects of intravitreal injection of indocyanine green (ICG) applied in macular hole surgery on retinal functional, morphology, and histologic changes. Eighteen (18) New Zealand albino rabbits were divided equally into three groups (6 rabbits in each). In Group A, both eyes of each rabbit were vitrectomized by perflouropropane gas compression. One (1) month later, 0.1 cc of different doses of ICG was injected into the vitreous in the left eyes. In the right eyes, 0.1 cc of balanced salt solution was injected intravitreally, allowing them to serve as control eyes. In Group B, the same doses of ICG were injected intravitreally. ICG was washed out by fluid-fluid exchange 3 minutes after injection. In Group C, the same doses of ICG were injected intravitreally in nonvitectomized eyes. Scotopic and photopic electroretinogram (ERG) recordings and indirect ophthalmoscopy examinations were performed to detect any functional and morphologic changes. Rabbit eyes were enucleated 4 months after ICG injections to observe histologic changes. Significant decreased of scotopic and photopic ERG amplitude and marked histologic changes were noted in eyes injected with 0.5 mg/cc and 0.1 mg/cc of ICG in nonvitrectomized eyes (Group C). In vitrectomized eyes (Group A), decreased scotopic and photopic ERGs and mild histologic changes were noted in eyes injected with 0.5 mg/cc, but no histologic changes were noted in eyes injected with 0.1 mg/cc. There was a transient, mild decrease in scotopic and photopic ERGs and no morphologic changes were noted in the eyes with fluid-fluid exchange (Group B). The toxicity of intravitreous ICG is dose- and time-dependent. ICG at 0.5 mg/cc, with short exposure time, is recommended in macular hole surgery.     

Risk factors for wound infection after cholecystectomy.

BACKGROUND AND PURPOSE: Surgical site infection (SSI) after cholecystectomy is a common problem. The aim of this study was to identify the possible risk factors for the development of SSI. METHODS: 545 consecutive patients who received open (125) or laparoscopic (420) cholecystectomy due to gallbladder disease during the years 1998 to 2000 were included in the study. Potential risk factors including clinical features, biochemical data, and operative types were analyzed by univariate and multivariate analysis. RESULTS: The overall incidence of SSI was 4.4% (24/545). The wound complication rate was significantly lower in the laparoscopic group than in the open group (1.4% vs 14.4%, respectively). Factors associated with SSI found by univariate analysis (p < 0.05) included age, gender, acute cholecystitis, white blood cell count, serum albumin, blood glucose and bilirubin level, type of surgery, operative time and positive bile culture. Stepwise logistic regression analysis showed that abnormal blood glucose [odds ratio (OR), 4.7; 95% confidence interval (CI), 1.6 to 13.5], positive bile culture (OR, 3.5; 95% CI, 1.2 to 10.4), and open cholecystectomy (OR, 4.3; 95% CI, 1.3 to 13.6) were the most significant predictors of SSI. CONCLUSION: Poor control of diabetes mellitus before surgery, positive bile culture and open cholecystectomy significantly increased the rate of SSI. These findings indicate that better control of diabetes mellitus, and appropriate selection of surgical procedure and antibiotic regimen in the management of high-risk patients may reduce the incidence of postoperative SSI.     

PAPⅠ基因在实验性急性胰腺炎模型大鼠中的表达

目的研究胰腺炎相关蛋白Ⅰ(pancreatitis assoc iated prote inⅠ,PAPⅠ)在急性胰腺炎(acute pancreatitis,AP)动物模型胰腺组织中的表达特点及意义。方法大鼠轻型胰腺炎(m ild acute pancreatitis,MAP)和重型胰腺炎(severe acute pancreatitis,SAP)模型由逆行胰胆管注射1.5%及3.0%牛磺胆酸钠制备。采用反转录聚合酶链反应(RT-PCR)法检测胰腺组织PAPⅠmRNA的表达,同时检测胰腺组织病理改变、湿/干质量比率、腹水量以评价炎症程度。结果PAPⅠmRNA在正常对照组无表达,AP造模后6 h即明显升高,24 h达高峰,48 h迅速下降。SAP组PAPⅠmRNA表达水平在6、24、48、72 h各时间点均显著高于MAP组(P<0.05)。同时PAPⅠmRNA表达与胰腺组织病理、胰腺组织湿/干质量比率和腹水量相关。结论PAPⅠmRNA的表达变化与AP时胰腺组织损伤程度相关。     

Six-month nocturnal nasal positive pressure ventilation improves respiratory muscle capacity and exercise endurance in patients with chronic hypercapnic respiratory failure.

BACKGROUND/PURPOSE: This study was designed to investigate the effects of 6 months of nocturnal nasal positive pressure ventilation (NNPPV) on respiratory muscle function and exercise capacity in patients with chronic respiratory failure. METHODS: A prospective, randomized, controlled design was used. Twenty-nine patients with chronic respiratory failure were enrolled and allocated to either the NNPPV (n = 14) or control group (n = 15). Patients in the NNPPV group received bi-level positive pressure ventilation via nasal mask for 6 consecutive months. Arterial blood gas, respiratory muscle assessment and 6-minute walk test (6MWT) were performed before and after the 6-month NNPPV intervention. Respiratory muscle function was assessed using the variables of maximal inspiratory pressure (Pimax), maximal expiratory pressure (Pemax), and maximum voluntary ventilation (MVV). RESULTS: Subjects in the NNPPV group showed a significant improvement in blood gas exchange and increased 6-minute walk distance (6MWD) compared to baseline and the control group. The 6MWD was significantly increased from 257.1 +/- 114.1 to 345.2 +/- 109.9 m (34.3%) in the NNPPV group. NNPPV also significantly improved MVV and Pimax relative to baseline. MVV was significantly increased from 19.2 +/- 6.5 to 22.3 +/- 7.1 L/min (16.1%) in the NNPPV group (p < 0.05). Furthermore, there was a significant correlation between the magnitude of MVV improvement and 6MWD change. CONCLUSION: The 6-month NNPPV treatment significantly decreased the partial pressure of carbon dioxide and improved daytime respiratory muscle function, thus contributing to exercise-capacity increase in patients with chronic respiratory failure.