Brain abscess in Saudi Arabia

There are significant variations among countries in the incidence of brain abscess. We report here 26 cases of brain abscess treated at the Neurosurgery Department of King Faisal University and Dammam Central Hospital Saudi Arabia over a six year period (1982–1988). This is 2.3% of total admissions to the two neurosurgery departments serving a population of approximately 1.2 million in the same period.Young males were most often affected (M/F ratio 3.3:1; 31% were less than 15 years old, 46% aged between 15–39 years, and 23% older than 40 years). Streptococcus was found to be the most common microorganism (38.4%). Mixed infection was seen in 15.3%, and sterile abscesses were found in 11.5% of the patients after aerobic and anaerobic cultures of the pus. Chronic otitis media and paranasal sinusitis predisposed the patients to abscess formation in 57.6% of the cases. The temporo-parietal area was the commonest site. Epilepsy was a complication in 30.7% of our patients, and the mortality rate was 15.3%.     

Autopsy findings in two cases of neonatal herpes simplex virus infection: detection of virus by immunohistochemistry, in situ hybridization and the polymerase chain reaction

We describe the pathological findings in two fatal cases of neonatal infection with herpes simplex virus. One had an encephalitis caused by herpes simplex virus type 2 (HSV-2); the other had a disseminated infection with herpes simplex virus type 1 (HSV-1). Confirmation of the diagnosis was obtained by use of the polymerase chain reaction to amplify viral DNA from paraffin sections of autopsy tissues. By using primers which amplify fragments of the HSV-1 thymidine kinase gene and HSV-2 glycoprotein gene respectively it was possible to discriminate between infection with HSV-1 and HSV-2. In contrast, immunohistochemistry and in situ hybridization using commercially available reagents did not distinguish between HSV-1 and HSV-2 infection. However, immunohistochemistry and in situ hybridization are probably more reliable than the polymerase chain reaction for assessment of the distribution of virus in different tissues.     

Intraperitoneal infection with Salmonella abortusovis is partially controlled by a gene closely linked with the Ity gene.

The aim of the present study was to determine whether the Ity gene, which controls the resistance to S. typhimurium infection in mice, also governs the resistance to S. abortusovis, a serotype specific for goat and sheep. During either i.v. or i.p. infection, BALB/c mice (Itys) were not able to control the growth of S. abortusovis and eventually died from infection. In contrast CBA (Ityr) or (C.CB)F1 (Ityr/s) mice were able to control the growth of these bacteria. Using congenic C.D2 Ityr mice, we found that the gene controlling resistance to S. abortusovis was tightly linked to the Ity gene on chromosome 1. Furthermore, in the spleen and the liver of backcross BALB/c x (CBA x BALB/c) mice, the S. abortusovis resistance phenotype cosegregated with the two alleles of the Len-1 gene, a gene tightly linked to the Ity gene. By contrast, in these backcross mice, the level of infection of the peritoneal cavity, the site of inoculation, did not correlated with the Len-1 phenotype of the animal. These results provide evidence that after i.p. inoculation the control of S. abortusovis growth in the spleen and the liver is controlled by the Ity gene, but also suggest that additional gene(s) regulate the number of bacteria at the site of inoculation.     

牙髓根管感染厌氧菌培养结果分析

从３４例牙髓根管感染中共分离出厌氧菌１１８株，经菌属分类依次为消化链球菌属，拟杆菌属，梭杆菌属，放线菌属，韦荣氏球菌属和珠网菌属，其中前３属为７７株，分离率为６５．３％，这一结果显示该３属细菌与极管感染有密切关系，是牙髓根管感染的优势菌。     

北京地区361名孕妇乙型肝炎流行病学研究

从1985年4月到1986年4月对361名孕妇进行的乙型肝炎流行病学横断面研究以及196名产妇一年随访研究的结果表明,361例孕妇的HBsAg阳性率为2.5%,抗-HBs阳性率为23.8%,抗-HBc阳性率为22.1%,HBV总感染率为31.3%;抗-HBs阳性、抗-HBs和抗-HBc共存阳性者占总阳性者的76.1%,说明人群感染HBV后大多产生了免疫力.1986年4月复查了196例产妇,133名在1985年HBV标记阴性者中有6人获得了HBV标记,HBV新感染率为4.5%;1例为急性乙型肝炎病人,5例为亚临床感染.HBV新感染者的感染途径不明,但医源性传播不能排除.1986年检查的148对夫妇中,男性HBsAg阳性率是女性的3.1倍(6.1%对2.0%),男性单独抗-HBc阳性率是女性的2.3倍(6.1%对2.7%),抗-HBs、抗-HBs和抗-HBc共存以及HBV感染率男女性间都无显著差异.     

Virulent and attenuated canine distemper virus infects multiple dog brain cell types in vitro.

Canine Distemper Virus (CDV) produces an encephalitis in dogs that varies with viral strain. We have studied the cell tropisms of two virulent strains (CDV-SH and CDV A75-17) and an attenuated strain, Rockborn (CDV-RO), in cultured canine brain cells. Infected cell types were identified by double immunofluorescent labeling of specific cell markers and viral antigens. All viral strains studied produced infection in astrocytes, fibroblasts, and macrophages. Neurons were not infected by CDV A75-17 but were rapidly infected by CDV-SH and CDV-RO. Multipolar oligodendrocytes were very rarely infected by any of the virus strains. In contrast, a morphologically distinct subset of bipolar oligodendrocytes were commonly infected by CDV-SH and CDV-RO. The kinetics of infection in the astrocytes, oligodendrocytes, neurons, and macrophages varied between strains. Both CDV-SH and CDV-RO rapidly infected bipolar oligodendrocytes, astrocytes, neurons, and macrophages by 14 days post infection while infection by CDV A75-17 was delayed until after 28-35 days post infection. The differences in the growth kinetics and cell tropisms for some brain cells, exhibited by the three viral strains examined in this in vitro study, may relate to the different CNS symptoms that these strains produce in vivo.     

Evidence for negative control in protein kinase C substrate specificity

The peptide Leu-Asp-Asp-Ser-Lys-Arg-Val-Ala-Lys-Arg-Lys-Leu-Ile-Glu, which corresponds to sequence 124 to 137 of c-erb-A protein, was synthesized and tested as substrate for protein kinase C (PKC). Although a typical recognition sequence for PKC, consisting of a cluster of basic residues, is found on the C-terminus side of serine, its phosphorylation was totally prevented by the presence of the two acidic residues on the amino-terminus side. Three analogs in which aspartyl residues were successively replaced with alanine were studied and the influence of the acidic side chain in modulating phosphorylation by PKC was thus possible to determine. The results show that the presence of a single aspartyl residue located in positions i-1 or i-2 with respect to the phosphorylable residue can almost totally abolish the positive effect of a highly favorable cluster of basic residues. These observations highlight the role of negative substrate specificity determinants in settling the protein substrate profile of protein kinase C.     

截瘫患者医院感染的监测及预防措施

目的了解截瘫患者医院感染的病原菌对药物敏感情况. 方法回顾分析我院自1996年9月～2003年11月,316例截瘫患者的有关临床资料. 结果 98例患者发生医院感染,医院感染率为31.01%,感染部位主要以呼吸道、皮肤软组织、手术切口、泌尿道感染为多;医院感染的病原菌主要是条件致病菌,以G-菌为主.结论医护人员必须严格无菌操作,根据细菌药敏结果合理选用抗菌药物,加强营养,提高患者机体抵抗力.     

妇产科患者术后使用镇痛泵引发尿路感染的临床探讨

目的 了解留置导尿所致尿路感染的发病率及影响因素。方法 采用前瞻性调查与回顾性调查相结合的方法,对妇产科手术后患者留置尿管而引发泌尿系感染率增高的原因进行调查和分析。结果 使用镇痛泵患者留置导尿后尿路感染率为5.45％,未用镇痛泵者的尿路感染率为0.21％,两者之间差异有高度显著性(P<0.005)。结论 镇痛泵不能滥用,使用时要避免诱发感染的因素。