Evaluation of the BinaxNOW Staphylococcus aureus test for rapid identification of Gram-positive cocci from VersaTREK blood culture bottles.

The ability of the rapid BinaxNOW Staphylococcus aureus (BNSA) immunochromatographic test (Alere Scarborough, Inc., ME) to accurately differentiate S. aureus from coagulase-negative staphylococci (CoNS) and other Gram-positive cocci (GPC) directly from VersaTREK blood culture bottles was evaluated.

Identification and characterization of plasmid-borne erm(T) macrolide resistance in group B and group A Streptococcus.

One hundred and seven group B Streptococcus (GBS) isolates and 344 group A Streptococcus (GAS) isolates were collected between 2005 and 2009 from 2 area hospitals and studied for resistance to erythromycin (ERY) and clindamycin (CLI) and the presence of the erm(T) macrolide resistance gene. The erm(T) gene was found in 5 (8%) of 61 erythromycin nonsusceptible GBS isolates and in 22 (55%) of 40 erythromycin nonsusceptible GAS isolates. The erm(T) gene in all 27 GBS/GAS erm(T) gene-positive isolates was located on a plasmid.

Prevalence of the erm(T) gene in clinical isolates of erythromycin-resistant group D Streptococcus and Enterococcus.

Among 48 erythromycin-resistant group D streptococci (GDS), 36 had the erm(T) resistance gene. erm(T) was also found in 4 of 31 erythromycin-resistant Enterococcus faecium isolates. This is the first report of the erm(T) gene in U.

Stealth dendrimers for drug delivery: correlation between PEGylation, cytocompatibility, and drug payload.

It is advantageous to utilize low generation polyamidoamine (PAMAM) dendrimers for drug delivery because low generations (generation 4.0 or below) have more biologically favorable properties as compared to high generations. Nevertheless, modification of low generation dendrimers with PEG to create stealth dendrimers is still necessary to avoid potential side effects by long term accumulation.

Identification of an erm(T) gene in strains of inducibly clindamycin-resistant group B Streptococcus.

Five inducibly clindamycin (CLI)-resistant group B Streptococcus (GBS) isolates, all negative for erm(A) and erm(B) genes, were found to contain erm(T), a gene previously reported in erythromycin-resistant animal isolates of Lactobacillus spp. and human isolates of Streptococcus bovis. One additional GBS isolate, constitutively resistant to CLI, was also positive for the erm(T) gene in addition to erm(B).

Rise of Streptococcus pneumoniae isolates containing both erm(B) and mef(E) genes from an adult tertiary care community hospital system.

The emergence of macrolide- and lincosamide-resistant Streptococcus pneumoniae is a worldwide concern. Of particular interest is the increasing prevalence of erythromycin and clindamycin-resistant isolates containing both erm(B) and mef genes. This study determined the prevalence of erythromycin and clindamycin resistance in 596 clinical S.

High rates of erythromycin and clindamycin resistance among OBGYN isolates of group B Streptococcus.

In vitro susceptibility testing on 200 Streptococcus agalactiae strains isolated during a 4-year period from vaginal/rectal specimens demonstrated a very high resistance rate for both erythromycin (54%) and clindamycin (33%). Methylase genes erm(B) and erm(TR) and efflux genes mef(E) and mef(A) were detected. Pulsed-field gel electrophoresis showed evidence of both clonal spread and multiclonal dissemination of resistant strains.

Persistently positive culture results in a patient with community-acquired pneumonia due to Legionella pneumophila.

We describe a patient with community-acquired pneumonia due to Legionella pneumophila serogroup 6. This patient was found to have bronchoalveolar carcinoma of the lung by means of cytologic testing in 1 of 2 bronchoalveolar lavage samples, but no lesions were visible on bronchoscopy. Despite intravenous administration of azithromycin to the patient, repeat culture and polymerase chain reaction showed persistence of Legionella; the isolates remained susceptible to azithromycin.

Exon 11 of the rat cholesterol esterase gene encodes domains important for intracellular processing and bile salt-modulated activity of the protein.

The rat pancreatic cholesterol esterase is a 74,000 molecular weight protein encoded by a gene with 10 introns and 11 exons. The last exon of the cholesterol esterase gene is the largest and is also the least conserved exon among the cholesterol esterase genes of various species. The current study investigates the functional role of the exon 11 domain in rat cholesterol esterase.

Aspartic acid 320 is required for optimal activity of rat pancreatic cholesterol esterase.

The acidic amino acid residue required for the catalytic activity of rat pancreatic cholesterol esterase has been identified in this study by sequence comparison with other serine esterases and by site-directed mutagenesis experiments. The sequence comparison studies identified 3 acidic residues in homologous domains between cholesterol esterase, acetylcholinesterase, cholinesterase, and Geotrichum candida lipase that may potentially be the catalytic acidic residue in these proteins. The role of Glu78, Asp79, and Asp320 in the catalytic activity of rat cholesterol esterase was then addressed by mutagenesis and expression of the cDNA.

Purification of pancreatic cholesterol esterase expressed in recombinant baculovirus-infected Sf9 cells.

A cDNA clone encoding the entire coding sequence of rat pancreatic cholesterol esterase (bile salt-stimulated lipase) was subcloned into the Baculovirus transfer vector pVL1392 and used to co-transfect Spodoptera frugiperda (Sf9) insect cells with wild-type Autographa californica nuclear polyhedrosis virus (AcNPV) DNA. Two recombinant proteins (M(r) 74 kDa and 64 kDa) reactive with anti-cholesterol esterase IgG were produced and secreted by the infected Sf9 cells in large quantities in a time-dependent manner. The 74-kDa protein was detectable in the cultured medium at the second day post-infection and increased progressively, reaching a level of 50 micrograms/ml of culture medium after 8 days.

Site-specific mutagenesis of an essential histidine residue in pancreatic cholesterol esterase.

The histidine residue essential for the catalytic activity of pancreatic cholesterol esterase (carboxylester lipase) has been identified in this study using sequence comparison and site-specific mutagenesis techniques. In the first approach, comparison of the primary structure of rat pancreatic cholesterol esterase with that of acetylcholinesterase and cholinesterase revealed two conserved histidine residues located at positions 420 and 435. The sequence in the region around histidine 420 is quite different between the three enzymes.

Identification of the active site serine in pancreatic cholesterol esterase by chemical modification and site-specific mutagenesis.

Chemical modification and site-specific mutagenesis approaches were used in this study to identify the active site serine residue of pancreatic cholesterol esterase. In the first approach, purified porcine pancreatic cholesterol esterase was covalently modified by incubation with [3H]diisopropylfluorophosphate (DFP). The radiolabeled cholesterol esterase was digested with CNBr, and the peptides were separated by high performance liquid chromatography.

Enzyme-linked immunoabsorbant assay of apolipoprotein AII in plasma, with use of a monoclonal antibody.

We produced a monoclonal antibody (C2-22) to human apolipoprotein (Apo) AII and describe its use in an enzyme-linked immunoabsorbant assay (ELISA) for Apo AII in human plasma and lipoprotein subfractions. No cross reactivity of the antibody with Apo CI, CII, CIII, E, or ablumin was detected. Apo AI and low- and very-low-density lipoprotein cross reacted by 0.

Expression of normal and tumor-associated antigens in human breast carcinoma.

The expression of six cytoplasmic/membrane antigens (beta 2-microglobulin, HLA, HLA-DR, carcinoembryonic antigen, and two breast tumor-associated antigens (TAAs), B6.2 and B72.3) was investigated in serial sections of 28 human breast carcinomas using monoclonal antibodies and the avidin-biotin complex immunoperoxidase technique.

Evaluation of the peroxidase-antiperoxidase method for demonstrating cell membrane B2-microglobulin.

The peroxidase-antiperoxidase (PAP) immunohistochemical technic was evaluated for its usefulness in studying B2-microglobulin (B2m) expression in the cell membrane of human tumor lines grown in athymic mice. Eleven human tumor xenograft lines expressing various amounts of B2m were used. B2m was assessed by three methods: PAP technic on formalin-fixed, paraffin-embedded tissue; indirect immunofluorescence on frozen sections; and radioimmunoassay on soluble tumor extracts.

Heterogeneity of beta 2-microglobulin in human breast carcinoma.

beta 2-microglobulin (beta 2m) content and distribution in human benign and malignant breast tissues have been investigated by immunohistologic means, and wide differences in the expression of this protein have been observed. The distribution of beta 2m as determined by indirect immunofluorescence was uniform throughout normal human and benign breast tumor tissues, as well as in human tumor xenografts grown in athymic mice, but marked difference in beta 2m content was demonstrated between individual tumors. In breast carcinomas, heterogeneity in beta 2m expression was found to exist within individual tumors.

Regional growth differences of human tumour xenografts in nude mice.

Human tumour cells of the HEP-2 and SW480 cell lines were inoculated subcutaneously into 4 locations on the athymic (nude) mouse lateral trunk. There was no difference in size between tumours grown on the right side of the body and those grown on the left. However, 4 weeks after inoculation, anterior tumours were 3 times as large as posterior tumours.

beta 2-microglobulin in human tumors heterografted into athymic mice.

Beta 2-microglobulin (beta 2m) content of several human tumor lines implanted into athymic mice was investigated. The concentration of this protein was found to vary greatly from tumor to tumor. The growth rate of the tumors was inversely related to the amount of the extractable beta 2m.

Release of beta 2-microglobulin by human tumors grown in nude mice.

Human tumors implanted subcutaneously into athymic mice produced human beta 2-microglobulin which was readily identified and quantified in mouse plasma. Implanted solid tumors of the lines Clouser, SW480, Hep-2, Capan-1, and HT-29 released amounts of beta 2-microglobulin directly related to tumor mass. The extractable beta 2-microglobulin per gram of tumor was constant for each cell line, but there was a 100-fold variation between the lines.

Influence of the mouse hepatitis virus (MHV) infection on the growth of human tumors in the athymic mouse.

The growth characteristics and histological appearance of tumors resulting from transplantation of the tumor lines HEp-2 and SW480 into pathogen-free and mouse hepatitis virus infected athymic mice were studied. Subcutaneous or intraperitoneal implantation 1 x 10(6) neoplastic cells into pathogen-free animals resulted in tumor growth. Subcutaneous transplants grew locally, surrounded by a capsule of connective tissue.

Monitoring the therapy of human tumor xenografts in nude mice by the use of lactate dehydrogenase.

With the use of circulating human lactate dehydrogenase (LDH) as a tumor marker, growth and remission of human tumor lines SW480, HEp-2, and Clouser, implanted into female BALB/c athymic nude mice, were followed during therapy. Three types of therapy were used: X-radiation, cyclophosphamide, and diphtheria toxin. After therapy tumor sizes were measured with calipers and compared to changes in the levels of circulating human LDH.

Growth patterns and metastatic behavior of human tumors growing in athymic mice.

The growth characteristics and metastatic behavior of human tumors growing in athymic nude mice were studied. Human tumor cell lines HEp-2 (carcinoma or larynx) and SW480 (colon carcinoma) were transplanted into athymic nude mice of BALB/c origin. Tumor cells (1 x 10(6) and 2 x 10(7)) were given either s.

Human lactic dehydrogenase as a marker for human tumor cells grown in athymic mice.

Human tumors implanted s.c. into athymic mice released lactic dehydrogenase (LDH) isoenzymes unique to human tissue.