Microbiology subsystem of a total, dedicated laboratory computer system.

The computer system used by the Microbiology Service of the Clinical Pathology Department, Clinical Center, National Institutes of Health is discussed. This microbiology subsystem is a part of a dedicated on-line laboratory computer system used by the entire department. The laboratory computer is connected on-line to a hospital computer which provides patient admission, transfer, and discharge data. Mark sense worksheets and cathode ray tube terminals are used for result entry and correction. Cumulative patient reports are printed. Results for both active and completed accessions can be easily retrieved on cathode ray terminals in the laboratory. All laboratory data are archived on magnetic tape from which a research data base and microfiched laboratory records are generated. The manner in which the system is integrated in the routine operation of the microbiology laboratory is emphasized. In addition, some of the costs, benefits, liabilities, and pitfalls associated with the introduction of the computer in the laboratory are reviewed. Finally, we have presented our concept of some of the future enhancements to our present system and some of the directions in which any future microbiology system might develop.     

AIDS-associated Kaposi''s sarcoma-derived cells in long-term culture express and synthesize smooth muscle alpha-actin.

Spindle-shaped cells from Kaposi's sarcoma lesions (AIDS-KS cells) were cultured for long periods in the presence of conditioned medium from activated CD4-positive T cells (HTLV-II infected transformed nonvirus producer) and characterized under in vitro conditions. To investigate a possible vascular origin, AIDS-KS cells were analyzed for the presence of smooth muscle alpha-actin, a differentiation marker for vascular smooth muscle cells. Immunofluorescence studies using a monoclonal antibody for smooth muscle alpha-actin demonstrated positive staining of the AIDS-KS cells (KS-3 and KS-4) but not by endothelial cells or fibroblasts. Northern blot analysis using an oligonucleotide probe unique for human smooth muscle alpha-actin indicated the expression of this gene by AIDS-KS cells. Similar analysis of biopsies from the KS lesion showed that in addition to the staining of smooth muscle cells associated with the blood vessels, the tumor-related spindle cells also stained positively. These cells were also analyzed for the expression of different growth factor genes. The platelet-derived growth factor (PDGF) A-chain gene was expressed at a moderate level. The insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-2 (IGF-2) genes were not overexpressed in relation to control cells. These data suggest that the analyzed AIDS-KS cells may be smooth muscle-like cells and therefore of vascular origin. Based on these results as well as previous reports, we speculate that cells of the immune system may regulate growth of cells in the vascular wall by a novel pathway.     

Construction and expression of recombinant plasmids encoding type 1 or D-mannose-resistant pili from a urinary tract infection Escherichia coli isolate.

Isolates of Escherichia coli from human urinary tract infections frequently express adherence properties found less often among normal intestinal isolates. These properties include adherence to human uroepithelial cells and primary monkey kidney cells, as well as D-mannose-resistant hemagglutination of human erythrocytes, and they are mediated by a pilus type different from type 1. The genes encoding this pilus type (pyelonephritis-associated pili, pap) and those encoding type 1 pili have been cloned from a urinary tract infection isolate of E. coli and transferred to an E. coli K-12 derivative. The recombinant plasmids were found to express functional pili and to endow the new host with all of the adherence properties of the urinary tract infection isolate. Both pilus types were found to be genetically distinct, and unlike the adherence genes from bovine, porcine, and human diarrheal isolates, both were found to be chromosomally encoded.     

Potential target sites in peripheral tissues for excitatory neurotransmission and excitotoxicity

Glutamate receptors (GluRs) are ubiquitously present in the central nervous system (CNS) as the major mediators of excitatory neurotransmission and excitotoxicity. Neural injury associated with trauma, stroke, epilepsy, and many neurodegenerative diseases such as Alzheimer's, Huntington's, and Parkinson's diseases and amyotrophic lateral sclerosis may be mediated by excessive activation of GluRs. Neurotoxicity associated with excitatory amino acids encountered in food, such as domoic acid and monosodium glutamate, has also been linked to GluRs. Less is known about GluRs outside the CNS. Recent observations suggest that several subtypes of GluRs are widely distributed in peripheral tissues. Using immunochemical and molecular techniques, the presence of GluR subtypes was demonstrated in the rat and monkey heart, with preferential distribution within the conducting system, nerve terminals, and cardiac ganglia. GluR subtypes NMDAR 1, GluR 2/3, and mGluR 2/3 are also present in kidney, liver, lung, spleen, and testis. Further investigations are needed to assess the role of these receptors in peripheral tissues and their importance in the toxicity of excitatory compounds. Therefore, food safety assessment and neurobiotechnology focusing on drugs designed to interact with GluRs should consider these tissues as potential target/effector sites.     

Exploring cancer register data to find risk factors for recurrence of breast cancer – application of Canonical Correlation Analysis

Background  

A common approach in exploring register data is to find relationships between outcomes and predictors by using multiple regression analysis (MRA). If there is more than one outcome variable, the analysis must then be repeated, and the results combined in some arbitrary fashion. In contrast, Canonical Correlation Analysis (CCA) has the ability to analyze multiple outcomes at the same time.     

Optimal use of the cytocentrifuge for recovery and diagnosis of Pneumocystis carinii in bronchoalveolar lavage and sputum specimens.

To facilitate the diagnosis of Pneumocystis carinii from bronchoalveolar lavage and sputum specimens, we have defined conditions for optimal use of the cytocentrifuge for this purpose. Centrifugation in the cytocentrifuge at 1,200 rpm for 10 min yielded the best recovery of P. carinii. To reliably ensure complete absorption of the fluid specimen from the cytocentrifuge chamber, it was necessary to use two absorption filters simultaneously. Different methods of treating induced sputum with mucolytic agents to process sputum with the cytocentrifuge were tried. Results of these studies and our current method for treating sputa are discussed. Comparisons of slides prepared by traditional centrifugation and by cytocentrifuge processing showed the latter to be equally effective for detecting P. carinii. The most prominent advantage of the cytocentrifuge was the much smaller area to review and consequently the shortened time required to read the slides.     

Prevalence of transmitted HIV-1 drug resistance and the role of resistance algorithms: data from seroconverters in the CASCADE collaboration from 1987 to 2003

OBJECTIVES: To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms. METHODS: The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm. RESULTS: Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used. CONCLUSIONS: Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed.     

Regulation of delayed-type hypersensitivity IV. Antigen-specific suppressor cells for delayed-type hypersensitivity induced by lipopolysaccharide and sheep erythrocytes in mice.

Mice injected subcutaneously with 1 x 10(8) sheep red blood cells (SRBC) developed high levels of delayed-type hypersensitivity (DTH) to SRBC 4-8 days after injection. Such DTH was suppressed when 100 microgram lipopolysaccharide (LPS) was injected intravenously 1-2 days before or at the time of SRBC injection. This suppression of DTH was transferable by spleen, lymph node, thymus and bone marrow cells to sensitized or normal syngeneic recipients, but could not be transferred by serum. Suppressor cells were not induced by LPS alone or SRBC alone, and they were antigen-specific since DTH to chicken red blood cells was not affected. The suppressor cells appeared in the spleen in optimum number 3-4 days after induction. They were theta-negative and Ig-positive as judged by antiserum plus complement treatment and by Ig rosette separation. Attempts to obtain soluble suppressor factor from the suppressor cells by sonication or in vitro incubation were unsuccessful. Mitomycin C treatment of the suppressor cells completely abolished the suppressor activity. Thus, LPS, in conjunction with antigen, appears to induce a population of specific suppressor B cells which are capable of regulating T cell function.