Incidence and antibiotic resistance of Salmonella spp. in ground turkey meat.

1. The objectives of this study were to isolate Salmonella spp. by conventional culture technique from ground turkey samples, to determine the seasonal distribution of Salmonella spp., to verify the isolates by PCR using primers based on oriC gene sequence, and to determine the antibiotic susceptibility profiles of the isolates. A total of 240 packaged fresh ground turkey samples marketed in Ankara were analysed between July 2004 and June 2005. 2. One hundred and ten out of 240 (458%) samples were positive for Salmonella spp. and confirmed by PCR. The distribution of Salmonella spp. was determined as 483, 550, 633 and 166%, during spring, summer, autumn and winter, respectively. Statistical analysis showed a significant difference for the prevalence of Salmonella spp. between winter and the other seasons. 3. Of the isolates, 54 out of 110 (490%) were resistant to one or more antibiotics tested. The highest resistance was observed to nalidixic acid (254%), followed by streptomycin (172%) and tetracycline (154%). 4. In conclusion, this is a disturbing finding, both for the high prevalence of Salmonella and the extent of antibiotic resistance. Ground turkey should be produced under suitable hygienic and technological conditions and the use of antimicrobials must be controlled by governmental agencies to protect public health from salmonellosis and from the consequences of increased resistance to the antibiotics.

Immunomagnetic separation and PCR detection of Listeria monocytogenes in turkey meat and antibiotic resistance of the isolates.

1. Conventional cultivation and immunomagnetic separation (IMS) cultivation methods were compared for the isolation specificity and sensitivity of L. monocytogenes from turkey meat samples. PCR was used to confirm the isolates. Disc diffusion was performed to determine the antibiotic susceptibility profiles. A total of 180 turkey meat samples collected from markets in Turkey were tested. 2. L. monocytogenes was detected in 23 samples (12.7%) by IMS and conventional cultivation. It was isolated from 16.6% (10/60), 11.6% (7/60) and 10.0% (6/60) of the meat cut, breast and leg samples, respectively. PCR assay was performed based on hlyA (LLO-listeriolysin O) gene specific primers. In all 23 (100.0%) isolates of the hlyA gene were determined. The disc diffusion test showed that 19 (82.6%) isolates were resistant to penicillin G and 17 (73.9%) to ampicillin. In addition, 8 isolates were partially resistant to erythromycin and 8 to streptomycin. 3. In conclusion, to safeguard public health turkey meat must be produced under hygienic and suitable technological conditions. Furthermore antimicrobials, as prophylactic or growth promoter agents, must be firmly controlled by governmental agencies.

hTERT gene expression levels and telomerase activity in drug resistant MCF-7 cells.

AIM: Cancer cells and some highly proliferative normal cells can stabilize telomere lengths by telomerase, which adds hexameric repeats to the ends of linear chromosomes. In this study, the activity of telomerase reverse transcriptase (hTERT) and its gene expression levels were investigated in paclitaxel, docetaxel, vincristine and doxorubicin resistant human MCF-7 breast adenocarcinoma cells. MATERIALS AND METHODS: Resistant cell lines were developed by stepwise selection of cells (MCF-7/S) in increasing doses of paclitaxel (MCF-7/Pac), docetaxel (MCF-7/Doc), vincristine (MCF-7/Vinc) and doxorubicin (MCF-7/Dox). Antiproliferative effects of anticancer drugs were evaluated by XTT assay and IC 50 values for different drugs were determined from cell proliferation curves. Expression levels of hTERT gene in sensitive and resistant cells were analyzed by RT-PCR. TRAP-Silver Staining assay was used to evaluate telomerase activities in these cells. RESULTS: When drug resistant and sensitive MCF-7 cells were compared no significant differences were observed in hTERT expression levels and telomerase enzyme activities. CONCLUSION: This report demonstrates that drug resistance developed against paclitaxel, docetaxel, vincristine and doxorubicin in MCF-7 cells is independent of the expression of hTERT gene and telomerase activity.

Basaloid squamous carcinoma of the hypopharynx and larynx associated with second primary tumors.

Basaloid squamous carcinoma is believed to be a histologically distinct variant of squamous cell carcinoma of the neck region with 11 cases reported. Two cases arising in the pyriform fossa and vallecula are reported, both of which were associated with second primary malignant tumors: esophageal small cell carcinoma and palatal squamous cell carcinoma, respectively. The authors suggest that basaloid squamous carcinoma may be associated with a high incidence of second primary tumors in the upper gastrointestinal tract or larynx.

Reduction to homozygosity involving p53 in esophageal cancers demonstrated by the polymerase chain reaction.

Loss of heterozygosity affecting chromosome 17p has been detected at high frequencies in a variety of human tumors, including cancers of the colon, breast, lung, and brain. One presumed target of these losses is p53, a tumor suppressor gene located on 17p. To our knowledge, loss of heterozygosity has not yet been reported at any locus, including p53, in human esophageal cancer. Moreover, current methods of detecting loss of heterozygosity depend on the availability of large amounts of high molecular weight DNA, making the study of small biopsy specimens or paraffin-embedded tissues problematic. We examined 52 primary human esophageal neoplasms for loss of heterozygosity affecting the p53 gene by using the polymerase chain reaction. Loss of one allele was detected in 52% of informative cases and was more common in squamous carcinomas than in adenocarcinomas. Southern blot analysis was used to confirm polymerase chain reaction-derived data. The identification of allelic loss in approximately half of the tumors analyzed supports the hypothesis that inactivation of p53 is involved in the pathogenesis of esophageal cancer.

Nodular regenerative hyperplasia: a cause of ascites and hepatomegaly after chemotherapy for leukemia.

Tender hepatomegaly and ascites occurred in a young woman receiving cytosine arabinoside and daunorubicin for acute myelogenous leukemia. Whereas veno-occlusive disease was suspected clinically, liver biopsy showed nodular regenerative hyperplasia with no evidence of hepatic vein abnormalities. It is postulated that nodular regenerative hyperplasia can be initiated by hepatotoxicity of chemotherapy agents used to treat leukemia and/or that these agents exacerbate clinical manifestations of this histological abnormality. Nodular regenerative hyperplasia should be added to the list of liver problems occurring in patients with leukemia.

Caseating hepatic granulomas in Hodgkin's lymphoma.

A 68-year-old man presented with recurrent Hodgkin's lymphoma after a 9-year disease-free interval induced by chemotherapy. In addition to histological evidence of recurrent Hodgkin's disease, the liver biopsy specimen showed extensive caseating granulomas. Cultures of bone marrow and liver tissue tested negative for Mycobacterium tuberculosis. No antituberculous treatment was administered, and the patient had an excellent clinical response to additional chemotherapy for lymphoma. Hodgkin's lymphoma should be added to the list of disease entities associated with caseating granulomas in the liver.

Resolution of inferior vena cava syndrome after embolization of a hepatic adenoma.

A 77-year-old man presented with severe pruritus and massive lower body edema. Computerized axial tomography of the abdomen showed a large hepatic mass compressing the inferior vena cava, and a liver biopsy specimen showed hepatic adenoma. Embolization of vessels feeding the hepatic tumor resulted in complete resolution of pruritus and ascites, and clinical remission has persisted for 1 year following partial obliteration of tumor vasculature. Angiographic ablation of tumor blood supply represents a nonoperative means for inducing clinical remission in patients with symptomatic hepatic adenoma who are at high surgical risk.

Development of a human stomach explant organ culture system to study the pathogenesis of Helicobacter pylori.

These studies were undertaken to define conditions under which Helicobacter (formerly Campylobacter) pylori and viable human gastric mucosa could coexist in tissue culture with the ultimate goal of developing an in vitro experimental model which could be used to study interactions between H. pylori and gastric epithelium. Antral gastric biopsies obtained at upper endoscopy were placed in culture in either CMRL-1066 or keratinocyte growth media and incubated at 37 degrees C in either an oxygen-enriched environment (45% O2, 50% N2, 5% CO2) or a standard oxygen environment (95% air, 5% CO2). Without selective antibiotics to suppress growth of non-H.-pylori organisms, H. pylori could not be isolated from most initially positive tissue even after only 2 h in tissue culture; however, when selective antibiotics were utilized in the tissue culture media, H. pylori was isolated from 9 of 14 initially positive cases after 24-72 h in tissue culture. There was little difference in the morphology of either surface or glandular epithelium in H.-pylori-negative explants between time zero and 48-hour cultures. However, H.-pylori-positive explants after 48 h in tissue culture showed a significant increase in injury to both surface and glandular epithelium when compared to time zero specimens. These data demonstrate that viable H. pylori and human gastric epithelium can be maintained in explant organ culture and suggest that this gastric mucosal explant culture system may be useful in studying the significance of H. pylori infection of human gastric epithelia.

Adenocarcinoma of the lower esophagus. A disease primarily of white men with Barrett's esophagus.

Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction.

Host-tumor cellular junctions: an ultrastructural study of hepatic metastases of bronchogenic oat cell carcinoma.

A light and electron microscopic study of a metastatic oat cell carcinoma of the lung in the liver of an elderly male is presented. In addition to the finding of a few desmosomes between the tumor cells, desmosomes were also found between the tumor cells and adjacent hepatocytes. The latter feature does not appear to have been reported previously in man.

The liver histology and frequency of clearance of the hepatitis B surface antigen (HBsAg) in chronic carriers.

Two hundred four volunteer blood donors with hepatitis B surface antigen found in their blood were followed for 3 to 44 months. The annual clearance rate of this antigen was 1.7%. Liver enzyme levels (aminotransferase) were elevated in 45 (22.1%) on at least one occasion, in 26 (12.7%) for one month or more, and in 13 for more than six months. Liver biopsies were performed on 17 chronic carriers with normal enzymes and nonspecific histologic abnormalities were found in 14 and mild diffuse hepatitis in three. Seventeen carriers with abnormal enzymes were biopsied, and specimens revealed chronic active hepatitis (CAH) in seven, including two with bridging necrosis and three with cirrhosis. CAH was found in 7 of 26 (26.9%) carriers with abnormal liver enzymes persisting for at least one month and 4 of 13 (30.8%) with abnormal liver enzymes for more than six months.

Cellular pathophysiology of hepatitis.

This paper represents an analysis of the subcellular events that occur in the human liver in viral hepatitis. They involve both hepatocytes and sinusoidal lining cells, including Kupffer cells. We present a new hypothesis concerning the sequence of events that occurs in hepatic parenchymal cells. These events begin with a virus-hepatocyte interaction that involves primary damage to the cell membrane. This is assumed to trigger a complex sequence of events that results in the characteristic hepatocellular impairment of this disease. These events center around ionic shifts resulting from an altered plasma membrane, leading to interactive events in hepatocyte organelles, mostly reversible, but resulting in the characteristic hepatocellular impairment.