Prenatal lead exposure in relation to gestational age and birth weight: A review of epidemiologic studies

Although the adverse effect on pregnancy outcomes at high levels of lead exposure in the workplace has been recognized for years, there is uncertainty regarding the impact of exposure at the lower community exposure levels commonly encountered today. This review summarizes the epidemiologic literature and discusses pertinent methodologic issues and possible sources of interstudy variation. The authors conclude that prenatal lead exposure is unlikely to increase the risk of premature membrane rupture but does appear to increase the risk of preterm delivery. Whether prenatal lead exposure decreases gestational age in terms of infants is unclear. Prenatal lead exposure also appears to be associated with reduced birth weight, but results vary in relation to study design and degree of control for confounding. Adjustment for gestational age, a possible confounder of the birth weight-lead exposure association, did not yield clearer results.     

Personal history,training, and worksite as predictors of back pain of nurses

Back pain among nurses is a common problem. Prior studies of this problem have been based on cross-sectional or retrospective data. This 18-month prospective study involving nurses newly graduated from nursing school investigated personal, worksite, and training factors associated with future risk of back pain. Each nurse underwent a preliminary interview and periodic follow-ups to identify those with back injuries. Contingency tables and logistic regression analyses demonstrated that prior significant back pain episodes (evidenced by previous job changes because of back pain, frequent medication use, etc.) were associated with increased future risk. Training at nursing school or on the job did not have a protective effect. This pilot study therefore suggests factors useful in placement and counseling of new nurses and indicates the need for further implementation of mechanical lift assist device use. © 1994 Wiley-Liss, Inc.     

In-vitro synthesis of steroid hormones in corpora lutea from normal women and women treated with 300 micrograms norethisterone.

The in-vitro oestradiol (E2) and progesterone (P) production by corpora lutea (CL) obtained at sterilization from 30 untreated women and 43 women treated with norethisterone (NET) 300 micrograms daily was measured. The CL were obtained at different stages of the luteal phase in the untreated women [luteinizing hormone (LH) 0 to +3, n = 7; LH +4 to +7, n = 7; LH +8 to +11, n = 9; LH +12 to menses, n = 7] and on days LH +8 to +11 or cycle days 22 to 26 in the NET-treated women. In the treated women, four types of ovarian reaction were identified. Four women showed ovarian reaction Type A (completely inhibited ovarian activity), 14 women Type B (marked follicular activity, but no luteal function), 12 women Type C (normal follicular activity, followed by insufficient luteal function) and 13 women Type D (apparently normal follicular and luteal activity). The CL were incubated in Eagle's medium with and without stimulation by human chorionic gonadotrophin (HCG) for 2 and 4 h. In the untreated women, P and E2 production increased significantly with both incubation time and stimulation by HCG throughout the luteal phase, except in the late luteal phase (LH +12 to menses) where P increased (P less than 0.01) only after 4 h stimulation by HCG. The maximal production of P was found after 4 h incubation with HCG stimulation of CL tissue in the early-mid luteal phase (LH +4 to +7).(ABSTRACT TRUNCATED AT 250 WORDS)     

Oocyte donation by gamete intra-Fallopian transfer to amenorrhoeic and cycling patients given replacement steroids

Thirteen procedures of oocyte donation by the gamete intra-Fallopiantransfer (GIFT) technique are described. The patients includedsix women with premature ovarian failure, four normally cyclingwomen with unexplained infertility who responded poorly to super-ovulationinduction in preparation for GIFT, and lastly one woman carrierof a 16/21 balanced translocation. Two patients had oocytesdonated on two occasions. Oocyte donors were recruited eitheramong the patients' relatives (n = 4), or among GIFT or IVFpatients (n = 8), who altruistically donated their extra oocytes.Donors were superovulated and oocytes collected laparoscopicallyor vaginally under ultrasound guidance. Donors did not sufferany complications. Recipients were given exogenous oestrogens,and exogenous progesterone was added from the day of donation.Seven clinical pregnancies were obtained (53.8% per attempt);one set of triplets aborted at 14 weeks. Donation took placeon replacement day 12–18 and pregnancies were obtainedin patients receiving oocytes throughout this temporal window.The increasing availability of embryo-freezing facilities willprobably reduce the number of ova available for donation. Therefore,the patients' families may become a precious source of donatedeggs, especially for those patients having large families, withstrong family ties.     

Substance P-like immunoreactivity in human cerebrospinal fluid

In a study to elucidate molecular mechanisms in pain, substance P-like immunoreactivity (SP-LI) was measured in lumbar CSF from 75 patients with lower back pain. Two samples – one before and one after lidocaine treatment – were obtained from each patient, and total SP-LI was measured in unfractionated (no HPLC) samples. SP-LI data were separated into three categories: placebo responders, pharmacological responders, and pharmacological non-responders. A significant difference was observed between the total SP-LI measurement of first and second samples of pharmacological non-responders. Distribution of SP-LI immunoreactive molecular species in two CSF patient samples (no ODS) was analyzed with a combination of reversed phase (RP) HPLC and RIA. Immunoreactivity in collected HPLC fractions was measured at calibrated retention times of synthetic SP-sulfoxide (SP-O), SP, and SP_5–11. Qualitative and quantitative differences in those HPLC-RIA metabolic profiles were observed within and between those two patients' samples. These data indicate that the type and amount of SP metabolism and SP precursor-processing differs in CSF between these two representative patients and within the short amount of time elapsed between acquiring these two samples.     

Klinefelter's Syndrome: Hypogonadism,abnormal carbohydrate metabolism. Is it a result of biotin deficiency?

The aetiology of Klinefelter's Syndrome is not known. The causative factor(s) must explain the hypogonadism, low androgen levels, the disordered carbohydrate metabolism and the commonly associated psychiatric conditions. A biotin deficient/dependent state can account for the above. A biotin deficient Klinefelter's Syndrome patients with the above is described. The possible role of biotin in the primary, secondary and tertiary prevention of Klinefelter's Syndrome needs further research.     

二尖瓣置换术围手术期硝普钠的应用

本文介绍了20例二尖瓣置换术病人围手术期使用硝普钠的经验。术中和术后早期使用硝普钠可降低肾素-血管紧张素系统的活性、减轻外周血管阻力和后负荷,增强泵血功能,从而使心脏指数升高,降低术后高血压和肺水种的发生率。体外循环停止后,硝普钠与低浓度升压药并用可增强心肌收缩力,预防低排综合征     

Plasma thrombomodulin level in very low birthweight infants at birth

Objective: Plasma soluble thrombomodulin level reflects endothelial damage. The plasma thrombomodulin level at birth is increased in asphyxiated full-term infants. There is no report of plasma thrombomodulin level in premature infants. To determine the thrombomodulin level in premature infants and whether it might reflect endothelial damage, we examined the plasma thrombomodulin level in very low birthweight (VLBW) infants at birth. Methods: Forty-five VLBW infants, of whom 14 had perinatal asphyxia complications, were recruited. As a control, 50 full-term infants wimout complications were also studied. Plasma thrombomodulin concentration, pH, base deficit, serum creatinine and D-dimer concentration, platelet count and fibrinogen concentration were measured within 1 hour after birth. Results: There were significant differences in plasma pH, creatinine concentration, platelet count, antithrombin in activity and D-dimer concentration between VLBW infants and full-term infants. Plasma thrombomodulin concentration (39. 0 (16. 6–93. 7) vs 27. 0 (16. 6–39. 1) μg/L, p < 0. 0001) and plasma taombomodulin-to-serum creatinine ratio (0. 82 (0. 19–2. 65) vs 0. 47 (0. 24–0. 70) μg/μmol, p < 0. 0001) were significantly higher in VLBW infants than those in full-term infants. By univariate analyses for all neonates, there were significant relations between plasma thrombomodulin concentration and gestational age, birthweight, plasma pH, creatinine concentration, platelet count and antithrombin in activity. A stepwise multiple linear regression model using the above variables as dependent factors showed only birthweight contributed significantly to plasma thrombomodulin concentration (plasma thrombomodulin concentration (μg/1) = 45. 677–0. 006 (birthweight; g), r²= 0. 323, p < 0. 0001, n= 94). Plasma thrombomodulin concentration and plasma thrombomodulin-to -serum creatinine ratio in VLBW infants with asphyxia were higher than in those without asphyxia, but not significantly different (43. 2 ± 17. 7 vs 38. 3 ± 8. 5 μg/1 and 0. 92 ± 0. 60 vs 0. 83 ± 0. 37 μg/μmol). Conclusion: Plasma thrombomodulin level in VLBW infants shows a high value at birth, and we consider the main factor responsible for this elevation may be endothelial damage or low clearance rate of thrombomodulin, which may be related to early gestational age.     

Survival of low birthweight infants in central Queensland

The survival of low birthweight infants £2000g born in the central Queensland area during the years 1979 to 1991 was examined. Five hundred and sixty such infants were either delivered at one of the two Rockhampton obstetric units (Rockhampton Base Hospital and the Mater Misericordiae Hospital) or retrieved from outlying central Queensland areas. Both hospitals had intensive care nurseries capable of ventilation and infants were transferred to tertiary centres only for cardiac or surgical treatment. The study involved all liveborn infants', including those with lethal malformations and all deaths up to the time of discharge. Survival rates were as follows: £500 g 0%, 501 £750 g 30%, 751 £1000 g 51%, 1001 ± 1500 g 79%, 1501 £2000g 93%. The survival of Aboriginal infants and outborn infants were found to be essentially the same as the overall group.     

我省流通领域阿莫西林制剂质量现状

目的:了解流通领域中阿莫西林制剂的质量状况。方法:在全省各市县的部分医药经营企业,抽取阿莫西林胶囊及干糖浆共54批样品,按国家药品标准进行全检后,对其检验结果进行统计分析。结果:不合格的项目有含量、胶囊剂溶出度、干糖浆粒度。该药物制剂的标示百分含量普遍偏低。结论:影响该产品质量的主要项目是含量和溶出度,含量偏低的主要原因是厂家的低限投料,应予以充分重视。