Detection of microbial contamination in foods before they go on to the market can help prevent the occurrence of foodborne illness outbreaks. Current methods for the detection of Escherichia coli are limited by time-consuming procedures, which include multiple culture incubation steps, and require several days to get results. This unit describes the development of an improved rapid flow-cytometry-based detection method that has greater sensitivity and specificity.
View Article and Find Full Text PDFStandard methods to detect Escherichia coli contamination in food use the polymerase chain reaction (PCR) and agar culture plates. These methods require multiple incubation steps and take a long time to results. An improved rapid flow-cytometry based detection method was developed, using a fluorescence-labeled oligonucleotide probe specifically binding a16S rRNA sequence.
View Article and Find Full Text PDFThe Bacteriological Analytical Manual (BAM) method currently used by the United States Food and Drug Administration (FDA) to detect Escherichia coli O157:H7 in spinach was systematically compared to a new flow cytometry based method. This Food and Drug Administration (FDA) level 2 external laboratory validation study was designed to determine the latter method's sensitivity and speed for analysis of this pathogen in raw spinach. Detection of target cell inoculations with a low cell count is critical, since enterohemorrhagic strains of E.
View Article and Find Full Text PDFFoodborne illnesses occur in both industrialized and developing countries, and may be increasing due to rapidly evolving food production practices. Yet some primary tools used to assess food safety are decades, if not centuries, old. To improve the time to result for food safety assessment a sensitive flow cytometer based system to detect microbial contamination was developed.
View Article and Find Full Text PDFContamination of wood waste with chromated copper arsenate greatly limits recycling opportunities for the wood waste as a whole. Separation of CCA-treated wood from other wood types is one means by which such contamination can be removed. The purpose of the current study was to evaluate two detector technologies for sorting CCA-treated wood from other wood types.
View Article and Find Full Text PDFMalignant pleural mesothelioma is a rare tumor that has been difficult to study. Because of disappointing treatment results, malignant pleural mesothelioma has remained an area of active research and development. A clinicopathologic review is performed in light of several problematic issues involving diagnosis, staging, natural history, and treatment.
View Article and Find Full Text PDFCentral venous line malpositioning in the left mediastinum is a rare event. A case of left superior intercostal vein central venous line placement is reported. Chest radiographs, especially lateral views and contrast studies, are useful for position evaluation.
View Article and Find Full Text PDFTransforming growth factorbeta1 (TGFbeta1) elicits a multitude of cellular responses from the epithelial-derived human colon cancer Moser cells. TGFbeta1 induces the expression of laminin and fibronectin, and previous studies show that the induction of fibronectin is functionally associated with the regulation of carcinoembryonic antigen (CEA) expression by TGFbeta1 (Huang and Chakrabarty, 1994, J Biol Chem 269:28764-28768). In this study we constructed antisense laminin chain-specific expression vectors and determined their efficacy in blocking the expression and the induction of the large multichain laminin molecule by TGFbeta1.
View Article and Find Full Text PDFBackground And Objectives: Small cell carcinoma of the gallbladder is rare with only 36 cases reported in the literature. Early reports demonstrated an extremely poor prognosis for this histologic type. Five new cases are reported and the previous experience in the literature is reviewed to further clarify the clinical behavior of this malignancy.
View Article and Find Full Text PDFBackground: Conventional therapy for pleural mesothelioma has met with disappointing results.
Methods: From 1991 to 1996, 40 patients with malignant pleural mesothelioma were treated with surgical resection followed by immediate intracavitary photodynamic therapy.
Results: The series included 9 women and 31 men with a mean age of 60 years.
Transforming growth factor beta1 (TGFbeta1) inhibits cellular proliferation and induces the expression of the matrix adhesion molecules fibronectin (FN) and laminin (LM) in a concurrent manner, followed by the induction of the intercellular adhesion molecule carcinoembryonic antigen (CEA) (collectively designated as adhesion responses) in TGFbeta1-responsive human colon carcinoma cells. Exactly how TGFbeta1 controls cellular adhesion and proliferation is poorly understood. In the present report, we showed that down-regulating protein kinase Calpha (PKCalpha) expression blocked the induction of these adhesion responses by TGFbeta1, showing that PKCalpha is a postreceptor focal point controlling the induction of these molecules.
View Article and Find Full Text PDFBackground: When given during pregnancy, the drug 3'-azido-2',3'-dideoxythymidine (AZT) substantially reduces maternal-fetal transmission of human immunodeficiency virus type 1 (HIV-1). However, AZT has been shown to be carcinogenic in adult mice after lifetime oral administration. In this study, we assessed the transplacental tumorigenic and genotoxic effects of AZT in the offspring of CD-1 mice and Erythrocebus patas monkeys given AZT orally during pregnancy.
View Article and Find Full Text PDFA case of subclavian artery obstruction by tube thoracostomy for penetrating trauma is presented. The obstruction was not physiologically significant; however, it did impede the assessment of the subclavian artery for potential injury using emergency center arteriography. The difficulty was easily corrected with repositioning of the chest tube.
View Article and Find Full Text PDFA previous attempt to model transplacental cisplatin exposure and genotoxicity employed several pregnant Erythrocebus patas monkeys; most of the animals were exposed near the end of gestation and cisplatin-DNA adduct analyses included only genomic DNA. Here, both genomic and mitochondrial DNA adduct formation have been determined in fetuses from two pregnant monkeys exposed at the end of the second trimester of gestation. Multiple fetal tissues were obtained after doses of 0.
View Article and Find Full Text PDFTwo chimpanzees were inoculated subcutaneously with the wild-type Oka strain of varicellazoster virus (VZV). Viral DNA was detected in peripheral blood mononuclear cells of both animals using the polymerase chain reaction (PCR) shortly after inoculation. Ten days after inoculation both animals developed an erythematous, papular rash near the site of inoculation that extended into the adjacent dermatome.
View Article and Find Full Text PDFN-nitrosodimethylamine (NDMA) is a human cancer initiator suspect. Ethanol, a cancer risk factor, may synergize with nitrosamines by suppressing hepatic clearance, to increase internal exposure. A limitation to these hypotheses is lack of activation of NDMA by many rodent tissues.
View Article and Find Full Text PDFHuman colon cancer cell lines express epidermal growth factor (EGF) mRNA, secrete EGF and may respond to it via the cell-surface EGF receptor (EGFR). Expression of these molecules in human colon and colon tumor, however, is not clear. Reverse transcription-polymerase chain reaction (RT-PCR) analyses of RNA prepared from paired normal human colon and colon tumor samples from 12 individuals followed by Southern blotting analyses of the RT-PCR products revealed a major fragment of 527 bp and a minor fragment of 404 bp that hybridized to a human EGF cDNA probe under stringent conditions.
View Article and Find Full Text PDFCancer Epidemiol Biomarkers Prev
March 1995
Transforming growth factor alpha (TGF alpha), a polypeptide growth-stimulating factor, has been implicated to play a role in the progression of gastrointestinal (GI) cancer. It has been suggested that TGF alpha expression in tumors or TGF alpha in the biological fluids of cancer patients may have tumor marker value. The serum levels of TGF alpha in GI cancer patients have not been reported.
View Article and Find Full Text PDFThe infectivity titer of a standard stock of the SAR-55 strain of hepatitis E virus (HEV) was determined in cynomolgus macaques (Macaca fascicularis) and the effect of dose on the course of the infection was examined by weekly monitoring of alanine aminotransferase (ALT) and anti-HEV levels. Antibody to HEV (anti-HEV) was measured with ELISAs based on ORF-2 recombinant antigens consisting of either a 55 kDa region expressed in insect cells or shorter regions expressed as fusion proteins in bacteria. The ELISA based on the 55 kDa antigen was generally more sensitive.
View Article and Find Full Text PDFPrevious studies suggest that transforming growth factor-alpha (TGF alpha) may have the potential of a tumor marker. Since the levels of serum TGF alpha in cancer patients and healthy individuals have not been reported, we determined the serum TGF alpha levels of 83 breast cancer patients and 74 healthy individuals by using a TGF alpha radioimmunoassay kit. All of the cancer patients' sera were positive for TGF alpha; their TGF alpha concentrations ranged from 210 to 740 pg/ml, with a mean of 353 +/- 98 pg/ml.
View Article and Find Full Text PDFPlatinum-DNA adducts in placenta and blood from a woman exposed to 200 mg/m2 of cis-diamminedichloroplatinum(II) (cisplatin) and 300 mg/m2 diamminecyclobutanedicarboxylatoplatinum(II) (carboplatin) for ovarian cancer have been documented by cisplatin-DNA enzyme-linked immunosorbent assay (ELISA) and atomic absorbance spectrometry (AAS). A patas monkey model was used to investigate transplacentally induced cisplatin-DNA damage in fetal tissues. During the last trimester of gestation, 5 patas monkeys were given multiple doses of cisplatin to mimic human ovarian cancer treatment.
View Article and Find Full Text PDFMarmosets injected intrahepatically with nucleic acids (cDNA and RNA transcripts) representing the full-length genome of the wild-type HM-175 strain of hepatitis A virus experienced acute hepatitis and seroconversion to hepatitis A virus capsid proteins. The hepatitis was comparable in severity to that caused by infection with the wild-type virus. The viral cDNA and the hepatitis A virus recovered from the feces of an injected animal contained the same marker mutation.
View Article and Find Full Text PDFSince DNA adducts have been detected in the placentae of pregnant women who smoke cigarettes, the importance of these adducts as biomarkers of fetal exposure and risk has been evaluated using a non-human primate as a model. Pregnant Erythrocebus patas monkeys on days 50, 100 or 150 of gestation (term = 160 +/- 5 days) were treated once with 5-50 mg/kg benzo[a]pyrene (B[a]P), p.o.
View Article and Find Full Text PDFA series of artemisinin-related endoperoxides was tested for cytotoxicity to Ehrlich ascites tumor (EAT) cells using the microculture tetrazolium (MTT) assay. Artemisinin [1] had an IC50 value of 29.8 microM.
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