The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis.

A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor.     

Ovarian Steroid Levels inSalamandra salamandra infraimmaculataduring the Reproductive Cycle

Gonadal steroid levels were determined in the ovary ofSalamandra salamandra infraimmaculataduring the reproductive cycle in populations from a xeric region in northern Israel. Varying proportions of previtellogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of mature oocytes were greater between December and April, after parturition. The levels of 17β-estradiol and testosterone rose during oocyte vitellogenesis and maturation. Levels of progesterone and 17α-hydroxy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females.     

经内镜胆管引流术在肝门部恶性胆管梗阻中的应用及其评价

肝门部恶性肿瘤手术切除率极低，临床处理十分棘手。作者采用内镜胆管引流术治疗此类肿瘤２８８例次（肝门部胆管癌１８４例、胆囊癌２３例、肝细胞癌侵犯肝门部胆管４７例、其他转移性肿瘤３４例），其中行内镜鼻胆管引流１６２例次、塑料内置管引流８０例次、放置可膨式金属胆道支架４６例、４例患者接受同期双内置管引流。引流总有效率为６７．０％，其中效果满意者４３．１％；４０例患者术后１个月内发生胆管炎，发生率为１３．８％，３例死亡；长期随访病例的平均存活期５．３个月。我们观察到治疗的效果与Ｂｉｓｍｕｔｈ分型有密切关系，如果全肝４０％以上的胆系得到引流，黄疸有望消退；左、右两侧胆管同时引流可扩大引流范围，提高疗效；应合理选择三种内镜胆管引流方法并适时灵活转换才能获得满意的疗效。结论：对于肝门部肿瘤，内镜胆管引流术是一种安全有效的治疗手段，可作为首选的姑息性治疗。     

镍作业工人细胞免疫功能、血清硒和过氧化脂质含量的变化

９６名镍作业工人测定结果：非特异酯酶阳性细胞百分率（ＡＮＡＥ＋％）为７６．８％±８．０％，Ｔ细胞亚群ＣＤ２、ＣＤ４、ＣＤ８阳性细胞百分率（ＣＤ＋２％、ＣＤ＋４％、ＣＤ＋８％）及ＣＤ＋４／ＣＤ＋８比值分别为６５．６％±１０．５％、５６．３％±１２．１％、３４．３％±８．２％和１．７６±０．６；酵母多糖刺激的外周血多形核白细胞化学发光（ＰＭＮ－ＣＬ）本底和峰值分别为４８±２３和３０７３±６８４ＣＰＳ／１０６ＰＭＮ；血清硒和丙二醛含量分别为１．２２±０．２３和４．７６±０．８８μｍｏｌ／Ｌ。与非镍作业的地区对照组比较，Ｔ细胞ＣＤ＋８％增高，ＣＤ＋４／ＣＤ＋８比值下降，化学发光的本底值降低，峰值增加，血清Ｓｅ含量下降，丙二醛含量升高。分析镍作业工人工龄与后三项指标变化的关系，工龄大于２０年与小于１０年有统计学上明显差别。这些观察指标为镍作业人员医学观察增加新的监护指标提供依据。     

Complement Killing of Yersinia enterocolitica and Retention of the Bacteria by Leucocyte Removal Filters

We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca²⁺ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca²⁺ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion.     

Synthesis of 14C‐labeled piperidines and application to synthesis of [14C]SCH 351125, a CCR5 receptor antagonist

1‐Benzyl‐4‐hydroxy[2‐¹⁴C]piperidine, a useful intermediate in labeled compound synthesis, was prepared from [¹⁴C]formaldehyde in high yield. The distribution pattern of ¹⁴C in the product is consistent with a mechanism involving reversible iminium ion formation and rapid equilibration of the iminium ion through a cationic aza‐Cope rearrangement. These steps precede the rate‐determining intramolecular cyclization step. SCH 351125 is a potent, selective CCR5 receptor antagonist with potential as a treatment for HIV infection. [¹⁴C]SCH 351125, required for metabolism studies, was prepared from 1‐benzyl‐4‐hydroxy[2‐¹⁴C]piperidine in six steps. [¹⁴C]SCH 351125 is a mixture of four atropisomers. Preparation of [¹⁴C]SCH 351125 besylate salt of the desired atropisomer pair is also described. Copyright © 2007 John Wiley & Sons, Ltd.     

Changing patterns of intellectual strengths and weaknesses in males with fragile X syndrome

Examined the changing profiles of intelligence in males with fragile X syndrome as these individuals increased in chronological age. Using a psychometric instrument designed to measure styles of information processing, 21 males aged 4 to 27 years were examined cross-sectionally in sequential processing, simultaneous processing, and achievement. The age of the subject was associated with age-equivalent levels of both simultaneous processing and achievement, but fragile X males did not show higher levels of sequential processing with increasing chronological age. Compared to younger fragile X males, the older subjects were more delayed in sequential processing skills relative to their abilities in other areas. A smaller longitudinal study confirmed the presence of a plateau in sequential processing among those subjects tested two times after the age of 10 years. Implications are discussed for diagnosis, intervention, and the matching of subject groups in mental retardation research.This research was supported in part by the John Merck Fund, the Joseph P. Kennedy, Jr. Foundation, NIH grants RR00125 and HD03008, and NIMH grants MH18268 and MH30929. We thank Wendy Marans and Joel Bregman for their comments on an earlier draft of this paper.     

有机氮源对红霉素发酵影响的具体分析

红色糖多孢菌的摇瓶培养基中使用不同有机氮源时红霉素的效价明显不同。通过对不同有机氮源所含营养成分的逐步回归分析,我们得到有机氮源中的苏氨酸为影响红霉素效价的主要因子。最后向对照培养基中添加苏氨酸,则使红霉素的效价比对照培养基提高了22.85%。