Molecular epidemiology and control of nosocomial methicillin-resistant Staphylococcus aureus infection in a teaching hospital.

BACKGROUND AND PURPOSE: Nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection is difficult to control. Due to a dramatic increase in the nosocomial MRSA infection rate at our hospital from 2000 to 2001, this study was conducted to identify the source of these infections and the effectiveness of control measures. METHODS: 179 healthcare workers (HCWs) were screened for carriage of MRSA. Starting in April 2001, all patients with MRSA infection or colonization were put in strict contact and cohort isolation. The bacterial isolates of HCW carriers and patients with MRSA infection from April 2001 to September 2001 were subjected to antimicrobial susceptibility testing by disk-diffusion method and molecular typing by pulsed-field gel electrophoresis (PFGE). RESULTS: Fifteen HCWs were found to be carriers of MRSA. They were all given topical mupirocin treatment. After these interventions, the nosocomial MRSA infection rate decreased from 1.23 to 0.53 per 1000 patient-days. All 61 MRSA isolates available for antimicrobial susceptibility testing and molecular typing were multidrug resistant. PFGE study revealed 2 predominant types, type C and type Y, comprising 36 and 12 isolates, respectively. CONCLUSIONS: The current study demonstrates the importance of measures to control nosocomial MRSA infections in hospitals that already have a high incidence of endemic MRSA infection. Elimination of carriage by healthcare workers, and strict contact and cohort isolation are the main effective measures.     

Absence of relaxation to lactate in human placental vessels of pregnancies with severe preeclampsia

OBJECTIVE: Our objective was to determine whether the observed relaxation to lactate and other agents in placental vessels of normal pregnancies is altered in severe preeclampsia.STUDY DESIGN: Isolated placental arteries and veins from women with severe preeclampsia and uncomplicated term pregnancies were precontracted with prostaglandin F_2α under 5% oxygen and 5% carbon dioxide with the balance nitrogen (Po₂ 35 to 38 torr) and then exposed to lactate (1 to 10 mmol/L, pH 7.4, n = 8 to 15), arachidonic acid (0.01 to 10 μmol/L, n = 6 to 13), nitroglycerin (1 nmol to 1 μmol/L, n = 4 to 12), or forskolin (0.01 to 10 μmol/L, n = 6 to 9). The response to lactate was also examined in placental vessels from appropriate-for-gestational-age preterm deliveries (n = 8) for comparison with a similar group with severe preeclampsia (n = 8). The t test and analysis of variance statistics were used.RESULTS: Relaxation to lactate was markedly inhibited in both placental arteries and veins of women with severe preeclampsia compared with vessels from uncomplicated term or preterm pregnancies. Responses to the other relaxing agents were not altered in the severely preeclampsia vessels.CONCLUSIONS: In severe preeclampsia absence of lactate-induced dilatation of placental vessels may contribute to the fetal complications associated with impaired blood flow and vasospasm.     

Use of epr oximetry with india ink to measure the po2 in the liver in vivo in mice

The partial pressure of oxygen (pO₂) of the liver in vivo in unanesthetized mice was determined using electron paramagnetic resonance (EPR) oximetry with India ink. The EPR spectra were obtained using a low-frequency (1.2 GHz) EPR spectrometer with a loop gap cavity resonator. The line width of the India ink used in this experiment was reversibly broadened by oxygen and was particularly sensitive to pO₂ below 30 torr. After the administration of India ink into the tail vein, the India ink particles were taken up mainly by Kupffer cells in the liver and in part by phagocytes in the spleen. The pO₂ measured in the normal liver was about 14 torr and was constant for the 2-week experimental period. The pO₂ decreased when measured at 1, 2, and 6 days after treatment with a hepatotoxin (carbon tetrachloride (CCI₄)); within 2 weeks, it returned almost to the initial level. Measurements by EPR at sacrifice of controls and CCI₄-treated mice indicated that more than 90% of the India ink went to the liver; the spleen contained 4.7% of total amount in control mice and 8.8% in CCI₄-treated mice when measured 2 weeks after the treatment. These data indicate the usefulness of India ink for measuring the pO₂ of the liver in vivo and that the pO₂ in the Kupffer cells is decreased when the liver is damaged by CCI₄.     

Development of specificity in corticospinal connections by axon collaterals branching selectively into appropriate spinal targets

Corticospinal projections in adult rodents arise exlusively from layer V neurons in the sensorimotor cortex. These neurons are topographically organized in their connections to spinal cord targets. Previous studies in rodents have shown that the mature distribution pattern of corticospinal neurons develops during the first 2 weeks postnatal from an initial widespread pattern that includes the visual cortex to a distribution restricted to the sensorimotor cortex. To determine whether specificity in corticospinal connections also emerges from an intially diffuse set of projections, we have studied the outgrowth of corticospinal axons and the formation of terminal arbors in developing hamsters. The sensitive fluorescent tracer 1, 1′, dioctadecyl-3, 3, 3′, 3′-tetramethylindocarbocyanine perchlorat (DiI) was used to label corticospinal axons from the visual cortex or from small regions of the forelimb or hindlimb sensorimotor cortex in living animals at 4–17 days postnatal. Initially axon outgrowth was imprecise. Some visual cortical axons extended transiently beyond their permanent targets in the pontine nuclei, by growing through the pyramidal decussation and in some cases extending as far caudally as the lumbar enlargement. Forelimb sensorimotor axons also extended past their targets in the cervical enlargement, in many cases growing in the corticospinal tract to lumbar levels of the cord. By about 17 days postnatal these misdirected axons or axon segments were withdrawn from the tract. Despite these errors in axon trajectories within the corticospinal tract, terminal arbors branching into targets in the spinal gray matter were topographically appropriate from the earliest stages of innervation. Thus visula cortical axons never formed connections in the spinal cord, forelimb sensorimotor axons arborized only in the cervical enlargement, and hindlimb cortical axons terminated only in the lumbar cord at all stages of development examined. Corticospinal arbors formed from collaterals that extended at right angles from the shafts of primary axons, most likely by the process of interstitial branching after the primary growth cone had extended past the target. Once collaterals extended into the spinal gray matter, highly branched terminal arbors formed within 2–4 days, beginning at about 4 and 8 days postnatal for the cervical and lumbar enlargements, respectively. These results show that specificity in connectivity is achieved by selectivty growth of axon collaterals in to appropriate spinal targets from the beginning and not by the later remodeling of intially diffuse connections. In contrast, errors occur in the initial outgrowth of axons in the corticospinal tract, which are subsequently corrected. Copyright © 1994 Wiley-Liss, Inc.     

巨乳缩小成形固定术

Twenty-eight breasts of 15 patients with macromastia underwent reduction mammaplasty from 1982 to 1989. We followed up these patients postoperatively for 6 months to 7 years. The follow-up time for 8 patients was over 1 year, and 4 patients over 5 years. And 3 patients labored and lactated. These 15 patients were satisfied with this operative results. The operative technology was based on Pitange's method. This method improved the site of the nipple, transposition of nipple-areola complex, and design of dermal pedicle, so that it had better effects in the breast shape, breast fixation and incision scar concealed. We suggest that the purpose of macromastia treated in reducing volume, improving breast shape, preserving lactating function. This paper also discusses the methods for nipple site, nipple-areola complex transposition, breast resection and mastopexy.     

叶天士治疗精浊（慢性前列腺炎）思路探析

我们在慢性前列腺炎的治疗中,通过学习叶天士《临证指南医案·淋浊》一篇,受益良深。古人虽受解剖学知识的限制,很难了解病变的具体部位,但从叶氏的医案中可以看出,他对“精浊”的认识与现代慢性前列腺炎基本吻合。叶氏认为,尽管淋证(泌尿系感染)与     

格林—巴利综合征患者血清和脑脊液中的抗硫脂抗体

探讨抗硫脂抗体与格林－巴利综合征（ＧＢＳ）的关系。方法采用固相酶联免疫吸附法对急性期ＧＢＳ患者血清和脑脊液（ＣＳＦ）中抗硫脂ＩｇＧ和ＩｇＭ抗体进行检测。结果ＧＢＳ患者血清和ＣＳＦ中抗硫脂ＩｇＧ及ＩｇＭ抗体的阳性率均明显高于正常对照组；血清中抗硫脂ＩｇＭ抗体滴度与标本收集时患者发病天数呈负相关（Ｐ＜０．０５），而血清中抗硫脂ＩｇＧ抗体滴度与临床分级（Ｐ＜０．０１）、ＣＳＦ中抗硫脂ＩｇＧ抗体滴度（Ｐ＜０．０１）呈正相关；血清中抗硫脂ＩｇＧ或ＩｇＭ阳性的ＧＢＳ患者，体检时有不同程度的感觉障碍患者为５６％，而血清中抗硫脂抗体阴性患者仅为１６％，两者之间差异有显著意义（Ｐ＜０．０５）。结论抗硫脂抗体可能在ＧＢＳ的病理过程中起重要作用     

深圳宝安3～7岁健康幼儿血清糖、离子、非蛋白含氮类化合物表达水平观察

目的观察深圳宝安3～7岁健康幼儿血清糖、离子、非蛋白含氮类化合物表达水平。方法采用OLRPUSAU-640全自动生化仪及OLRPUS诊断试剂、东欧生物诊断试荆，检测316例体检健康幼儿血清中Ca^＋＋、Mg^＋＋、P^＋＋＋、GLU、BUN、Cr、UA的含量。结果①．1组与4组及2组与3、4组Ca^＋＋组间方差分析，差异有统计学意义，P〈0.05。②．1组与2、3、4组Cr组间方差分析，差异有统计学意义P〈0．05。而Mg^＋＋、P^＋＋＋、GLU、BUN、UA组间方差分析差异无统计学意义，P〉0．05。结论笔者证实了3～4岁健康幼儿与6～7岁健康幼儿及4～5岁健康幼儿与5～7岁健康幼儿血清Ca^＋＋表达水平有差异。也证实了3～4岁健康幼儿与4～7健康幼儿Cr含量存在差异。由此可见，3～7岁健康幼儿建立自己的参考值是必要的。