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.     

Plasma amino acid concentrations in geriatric control and hip-fracture patients.

Changes in plasma amino acids, 24-h nitrogen balances, and resting metabolic expenditures (RMEs) were measured in 10 geriatric patients (aged 70-92 y) with hip fracture 1 d after surgical fixation during both a 24-h fasting state and while receiving total peripheral parenteral nutrition (TPPN) for 24 h at 1.5 g amino acids.kg-1.d-1 and 29-30 kcal.kg-1.d-1 and compared with 19 healthy volunteer subjects (aged 70-84 y). RME and 24-h urinary nitrogen losses were also elevated in the trauma patients during both fasting and TPPN. Positive nitrogen balances were evident in both groups during TPPN. Plasma total amino acid concentration was significantly lower in the trauma patients because of lower plasma concentrations of the nonessential amino acids. Phenylalanine and methionine concentrations were significantly higher and lysine lower in the trauma group. In addition, evaluation of the essential amino acid ratios after fasting and TPPN reveal that there are no limiting amino acids during TPPN.     

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。     

原发性青光眼的激光治疗

目前在青光眼的临床治疗中，激光治疗已成为介于药物和手术治疗之间的一种方法，本文仅就原发性闭角型青光眼的激光周边虹膜透切术和开角型青光眼的激光滤帘成形术做一介绍。     

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.     

Man-Machine Interfaces in Computer Assisted Surgery

The clinical potential of computer assisted surgery (W) has been more and more widely acknowledged since CAS systems have been introduced into the operating room (OR) theater.

Especially the improvements in safety and accuracy are remarkable and strengthen the ties between surgeons and engineers. Tumor stereotaxis was introduced to neurological surgery in the early 1980s, and currently systems with and without robotic navigation are in use for specific medical indications. Recently, solutions for computer assisted orthopedic surgery were developed and applied to various anatomical regions. However, with the establishment of CAS in vivo, a new complex of problems, which was not present in the laboratory setup, was introduced: the man-machine interface.

Currently, the complexity of available CAS systems requires the presence of at least one system engineer (often called the “operator”) in the OR. As a consequence, there is no possibility for direct communication between the surgeon and the machine or software.

Most of the program steps involved in CAS and choices to be made intraoperatively have to be transferred to the software by means of communication of the surgeon with the operator. Particularly, the establishment of a relation between the virtual object (i.e., a medical image) and the surgical object (i.e., the patient), often denoted as “matching” or “skeletal registration” requires intensive interaction of the surgeon with the computer. A literature survey revealed that no CAS system in clinical use exists without a system engineer or a comparable person, and our clinical experience indicated that the matching process is a weak point in most systems. Because it appears to be contradictory to cost-reduction efforts in health care to have a highly paid specialist in the OR, this research evaluates strategies to facilitate the man-machine interface with the final goal of establishing a direct control of the system by the surgeon or the medical personnel traditionally present at surgery. Options to be investigated include 1) a CAS control panel (virtual keyboard) as an integrated component of the existing navigation system and 2) introduction of a commercial voice-recognition system. The implementation of these strategies into the existing CAS setup at the Department of Orthopaedic Surgery at the Inselspital (University of Bern) and clinical experience gained are reported     

经鼻给予神经生长因子对沙林染毒大鼠梨状皮质神经元的影响

目的 探讨经鼻给予神经生长因子(NGF)对沙林染毒大鼠脑组织梨状皮质区神经元的影响.方法 建立大鼠沙林染毒模型,常规治疗后经鼻给予NGF或生理盐水,24 h后采用HE染色和免疫组织化学染色观察梨状皮质区神经元的变化.结果 与空白对照组相比,经鼻给予生理盐水的大鼠梨状皮质区可见较多变性、坏死的神经元,神经元数量[(404.75±25.17)个/mm2]明显减少(39.44%);而经鼻给予NGF组变性、坏死的神经元较少,神经元数量[(651.94±36.02)个/mm2]减少不明显.结论 经鼻给予NGF可以减轻沙林染毒大鼠梨状皮质区损伤程度.经鼻给予NGF有可能成为针对沙林所致脑损伤的有效治疗手段.