The effect of the increasing prevalence of maternal obesity on perinatal morbidity

OBJECTIVE: In this study, we assessed the temporal trends and relative and attributable perinatal risks of maternal obesity over a 20-year period. STUDY DESIGN: We conducted a retrospective cohort study between 1980 and 1999 by using a computerized perinatal database of all women who received prenatal care and delivered their infants within a regional health care system. The main outcome measures were as follows: (1) annual mean body weight and the percentage of women classified as obese at the first prenatal visit (primary definition > or = 200 lb; secondary definitions > or = 250 lb, > or = 300 lb, body mass index > 29 kg/m(2)); and (2) relative and attributable risks of obesity for selected maternal and perinatal morbidities in successive 5-year periods. RESULTS: From 1980 to 1999, the mean maternal weight of women at the first prenatal visit increased 20% (144-172 lb), as did the percentage of women > or = 200 lb (7.3-24.4), the percentage > or = 250 lb (1.9-10.7), the percentage > or = 300 lb (0.5-4.9), and the percentage with a body mass index > 29 kg/m(2) (16.3-36.4), P < .01 for all. Controlling for maternal age, race, and smoking status, obese women were at increased risk at each period for cesarean delivery (range of adjusted relative risk, 1.5-1.8), gestational diabetes (range, 1.8-2.9), and large (> 90th percentile) for gestational age infants (range, 1.8-2.2). From the earliest 5-year period (1980-1984) to the most recent (1995-1999), the percentage of obesity-attributable cesarean deliveries more than tripled from 3.9 to 11.6. Similar percentage increases were observed for the obesity-attributable risks for gestational diabetes (12.8-29.6) and large for gestational age infants (6.5-19.1). Trends for secondary obesity definitions were similar, although the magnitude of the increased attributable risks was smaller. CONCLUSIONS: Efforts to reduce the frequency of certain perinatal morbidities will be constrained unless effective measures to prevent, or limit the risks of, maternal obesity are developed and implemented.     

Clinically occult, noncalcified breast cancer: serial radiologic- pathologic correlation in 27 cases

A serial radiographic-pathologic correlation based on specimen radiography was performed on 27 consecutive, clinically occult, noncalcified breast cancers to determine the frequency of and correlation between appearances at mammography, pathologic diagnoses, and the features of the histologic margins. Twenty (74%) of the lesions were infiltrating ductal cancers, five (19%) were intraductal cancers, and two (7%) were medullary cancers. Forty-one percent of these malignancies contained microscopic calcifications. Lesions demonstrated at mammography in these 27 cases consisted of a well-defined round mass (n = 1); well-defined lobulated masses (n = 2); indistinct round, oval, or lobulated masses (n = 7); irregular or mixed lesions (n = 7); spiculated masses (n = 9); and architectural distortion (n = 1). Histologic margins of infiltrating and intraductal cancers, created by several types of tumor-fat interfaces and surrounding reactive fibrosis, correlated with these radiographic appearances. Serial specimen radiographic-pathologic correlation can improve our understanding of the appearance of early breast cancer at mammography.     

Practice variation in the use of interventions in high-risk obstetrics.

OBJECTIVE: To assess the relationship between clinical, demographic, and site-of-care factors and the use of tocolysis and corticosteroid therapy in the treatment of premature labor. DATA SOURCE: Secondary clinical and demographic data collected for the five-center March of Dimes Prematurity Prevention clinical trial, 1983-1986. STUDY DESIGN: We used logistic regression analysis in assessing the clinical, patient, and care site factors associated with the use of tocolysis and corticosteroid therapy during episodes of premature labor occurring to women enrolled in the trial. The two interventions were not subject to control in the trial, but were provided according to customary practice at the care site. DATA EXTRACTION: A total of 4,625 episodes of labor occurring before 37 weeks gestation were identified from either preterm labor or preterm delivery records recorded for the 33,792 women enrolled in the trial. PRINCIPAL FINDINGS: The use of tocolysis, an intervention that attempts to control premature labor contractions and that was widely used in high-risk obstetrics, varied almost exclusively by clinical factors. The use of corticosteroid therapy, a little used but effective intervention that reduces respiratory complications in premature infants, varied significantly by site of care and was used less frequently across sites and clinical conditions for minority group patients. CONCLUSION: This study confirms the premise that practice variation on the basis of nonclinical factors occurs more commonly for interventions where there is more uncertainty about clinical indications and effectiveness. The study also identifies another area of clinical care in which the use of aggressive and relatively uncertain interventions is provided less frequently to minority group patients.     

Incompleteness of statutory notification of bacterial gastro-intestinal infection

A study was made of all potentially statutorily notifiable bacterial infections diagnosed in faecal samples submitted from symptomatic patients to a single microbiology laboratory during a six-month period. Salmonella spp, Campylobacter spp or Shigella spp were isolated from 167 patients and 51% of these were formally notified (54% of general practice patients and 47% of hospital patients). Forty-seven percent of cases of foodpoisoning (Salmonella spp. and Campylobacter spp) were notified as were 70% of cases of shigella infections. Notification was made on average 9.4 d after sending a specimen to the laboratory. A questionnaire used to ascertain the reasons for non-notification in 80 of 85 cases elicited replies in respect of 78 patients. Four patients infected with Salmonella spp or Campylobacter spp were said not to have been suffering from foodpoisoning. A variety of reasons was given for failing to notify the others, the most common were forgetfulness, not receiving the result of the specimen, or believing someone else had made the notification.     

Albumin gradients do not enrich Y-bearing human spermatozoa

The aim of this study was to evaluate objectively whether or not discontinuous albumin gradients enrich the proportion of Y-bearing human sperm. A blinded, collaborative trial design was employed whereby a licensed centre prepared the sperm fractions using licensed procedures, coded the sperm slides and then sent them to an independent laboratory for determination of the X:Y ratio in each sperm fraction using X and Y chromosome-specific probes and double label fluorescence in-situ hybridization (FISH). The identification codes and FISH results were collated by an independent third observer. Two albumin gradient methods which are currently used by licensed centres for male sex pre- selection, protocol 3 and modified protocol 3, were tested. Essentially the same results were obtained for the two methods. Highly motile sperm fractions were recovered from the albumin gradients, and the recoveries of motile spermatozoa (1.3-8.5%) were within the optimal range reported to produce maximal enrichment of Y-bearing spermatozoa. FISH analysis, however, revealed no enrichment for Y-bearing spermatozoa with either method, and the overall X:Y ratios were not significantly different from 1.0. Some samples showed marginal enrichment of Y-bearing spermaotozoa, whereas others showed marginal enrichment of X-bearing spermaotozoa. In conclusion, this collaborative study has demonstrated that the protocol 3 and modified protocol 3 albumin gradient procedures do not enrich Y-bearing spermatozoa. The clinical use of albumin gradients for male sex preselection should be reconsidered in the light of this and other evidence.      

癌化学预防药物的研究:一些酰胺化合物的合成

癌化学预防药物的研究：一些酰胺化合物的合成袁占亮，徐世平（中国医学科学院，中国协和医科大学药物研究所北京１０００５０）维甲类化合物的合成及生物活性研究，引起国内外学者的很大兴趣，尤其是对癌的化学预防方面的研究方兴未艾，是国际上公认为最成熟和最有希望的...