BRAF Activation Initiates but Does Not Maintain Invasive Prostate Adenocarcinoma

Prostate cancer is the second leading cause of cancer-related deaths in men. Activation of MAP kinase signaling pathway has been implicated in advanced and androgen-independent prostate cancers, although formal genetic proof has been lacking. In the course of modeling malignant melanoma in a tyrosinase promoter transgenic system, we developed a genetically-engineered mouse (GEM) model of invasive prostate cancers, whereby an activating mutation of BRAF^V600E–a mutation found in ~10% of human prostate tumors–was targeted to the epithelial compartment of the prostate gland on the background of Ink4a/Arf deficiency. These GEM mice developed prostate gland hyperplasia with progression to rapidly growing invasive adenocarcinoma without evidence of AKT activation, providing genetic proof that activation of MAP kinase signaling is sufficient to drive prostate tumorigenesis. Importantly, genetic extinction of BRAF^V600E in established prostate tumors did not lead to tumor regression, indicating that while sufficient to initiate development of invasive prostate adenocarcinoma, BRAF^V600E is not required for its maintenance.     

Auditory P300 event-related potential in tobacco smokers

The aim of this study was to elucidate the chronic effects of tobacco smoking on the P300, a neurophysiological index of cognitive function. Prospective study participants were recruited from a family medicine polyclinic. We selected 32 right-handed smokers who had smoked more than 15 cigarettes per day, by inhalation, for more than 2 years. The control population consisted of 32 right-handed, age-matched healthy individuals who had never smoked. Event-related potentials (ERPs) were recorded with the auditory “oddball” two-tone discrimination task. The data from the central (Cz) and frontal (Fz) electrodes were analyzed. The P300 and N1 amplitudes at Fz were lower in the study population compared to the control group. The early component of ERP, the measure of mental speed (N1) latency at Fz was prolonged in the study group compared to the controls, possibly because early cognitive processes such as sensory input or initial encoding of sensory information were delayed in this group. For those who smoke, a decreased N1 amplitude might indicate delayed information processing and possibly short-term memory disturbance. Thus, chronic tobacco smoking may produce prefrontal cognitive dysfunction.     

Primary non-Hodgkin's lymphoma of the rectum

BACKGROUND: Primary rectal lymphoma is a very uncommon disease, therefore, it has received little attention in the literature. Because of their rarity, rectal lymphomas are generally included in the group of large intestine lymphomas. CASE REPORT: We report here a case of primary rectal B-cell lymphoma in a 67-year-old woman. The tumor was originally located in the rectum without evidence of any other lymphoma-involved organ. Histological findings revealed diffuse large B-cell lymphoma. The clinical stage was IE according to the Ann Arbor system. International prognostic index (IPI) was I (low-intermediate risk). We preferred a non-surgical, organ-sparing treatment which started with chemotherapy followed by radiation. 12 months after the end of therapy, there is no sign of tumor recurrence in our patient. CONCLUSION: We suggest that histology-specific multidrug chemotherapy followed by radiotherapy seems to be a therapeutic approach that is appropriate fort this rare tumor.     

Effect of fluoride intoxication on endometrial apoptosis and lipid peroxidation in rats: role of vitamins E and C

Fluoride is a strong, hard anion and cumulative toxic agent. The effect of fluoride intoxication on lipid peroxidation in endometrial tissue and the protective effects of combinations of vitamins E and C in rats were studied. Additionally, the apoptotic changes in endometrial tissue were examined. Experimental groups were as follows: control group; a group treated with 100 mg/l fluoride (F group); and a group treated with 100 mg/l fluoride plus vitamins E and C (F+Vit group). The F and F+Vit groups were treated orally with fluoride for 30 days. Vitamins E and C were injected simultaneously at doses of 50 mg/kg day i.m. and 20 mg/kg day body weight i.p. Extensive formation of DNA strand breaks, the typical biochemical feature of apoptosis, was detected with the use of the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick and labeling (TUNEL) method. Malondialdehyde (MDA) levels were determined in uterine tissue of rats. Fluoride caused a significant increase in MDA levels (an important marker of lipid peroxidation) in the fluoride group compared with the controls (p<0.05). Vitamins E and C significantly reduced the fluoride-induced lipid peroxidation in the F+Vit group compared with the F group (p<0.05). Diffuse apoptosis in glandular epithelium and stromal cells was found in endometrial tissues of F treated rats by TUNEL method. The severity of these lesions was reduced by the administration of vitamins. From these results, it can be concluded that subchronic fluoride administration causes endometrial apoptosis, and lipid peroxidation may be a molecular mechanism involved in fluoride-induced toxicity. Furthermore, treatment with a combination of vitamins E and C reduced endometrial apoptosis caused by fluoride.     

Depression in a sample of Turkish type 2 diabetes patients.

Forty-one depressive and 57 nondepressive patients with non-insulin-dependent diabetes mellitus (NIDDM, type 2) were compared for demographic and clinical variables. The depressive patients were more likely to have a history of depression than non-depressive patients. The female patients were more likely to have depression than males. Results suggest that depression in NIDDM was only associated with female gender and previous depressive episodes.     

Which musculoskeletal complications are most frequently seen in type 2 diabetes mellitus?

This study aimed to investigate the prevalence of the most frequently occurring hand and shoulder complications in type 2 diabetes mellitus patients. The presence of cheiroarthropathy, frozen shoulder, Dupuytren's contracture and trigger finger was assessed in 102 type 2 diabetes mellitus patients and 101 age- and sex-matched non-diabetic controls. The relationship between these complications and patients' age, sex, duration of diabetes and glycaemic control was also analysed. Cheiroarthropathy, frozen shoulder and Dupuytren's contracture were significantly more prevalent in the diabetic group than in the control group. Females were slightly more affected with frozen shoulder than males and advanced cases (stage 2) of cheiroarthropathy occurred more frequently in females. Duration of diabetes was related to an increased risk of cheiroarthropathy. In conclusion, some musculoskeletal disorders are more prevalent in type 2 diabetes mellitus patients and this may be associated with glycaemic control, sex and duration of diabetes.     

Potential effects of zinc on information processing in boys with attention deficit hyperactivity disorder

PURPOSE: The aims of the present study were to investigate the relationship between plasma zinc levels and amplitudes and latencies of P1, N2, and P3 in parietal and frontal areas in children with ADHD, and to compare these zinc levels and event-related potentials (ERPs) indices with controls. METHODS: 28 boys with ADHD were divided into two groups according to plasma zinc levels: low zinc group (N=13, zinc level <80 microg/dL) and zinc non-deficient group (N=15, zinc level >or=80 microg/dL). ERP indices from parietal and frontal brain regions were recorded in children with ADHD and in 24 normal boys by using an auditory oddball paradigm. Plasma zinc levels were measured by an atomic absorption spectrophotometer. RESULTS: The plasma zinc levels were significantly lower in both ADHD groups (means are 65.8 microg/dL in low zinc group and 89.5 microg/dL in zinc non-deficient group) than controls (mean: 107.8 microg/dL; both p values <0.017). In ADHD compared to controls, the amplitudes of P3 in frontal and parietal regions were significantly lower, and the latency of P3 in parietal region was significantly longer (all p values <0.017). In low zinc ADHD group compared to zinc non-deficient ADHD group, the latencies of N2 in frontal and parietal region were significantly shorter (all p values <0.017). In addition, there was a medium but significant positive correlation between plasma zinc levels and amplitude and latency of frontal N2 wave in ADHD. CONCLUSIONS: These results can suggest that plasma zinc levels might have an effect on information processing in ADHD children, and lower zinc levels seem to affect N2 wave. Since N2 wave changes may reflect a different inhibition process, further studies are warranted to investigate the effect of zinc on inhibitory process in children with ADHD, and in low zinc and non-deficient ADHD groups.     

Does Helicobacter pylori infection play a role in lung cancer?

BACKGROUND: Helicobacter pylori infection is a world-wide common disease and leads to many gastrointestinal and respiratory illnesses. It is suggested that one of these respiratory illnesses is lung cancer. METHODS: Forty-three patients with non-small cell lung cancer and 28 control subjects have been included to this study. H. pylori status of the patients and controls was determined by immunoblot for the detection of IgG (RIDA Blot Helicobacter). All subjects were examined to evaluate the presence of VacA and CagA gene. RESULTS: Seropositivity of anti H. pylori IgG was significantly higher in cancer patients than in control groups, 40 (93%) and 12 (42%), respectively (P<0.01). Although both VacA and CagA seropositivity was high in lung cancer patients, only VacA positivity was statistically significant when compared with control subjects, 35 (81%) and 11 (42%), respectively (P<0.05). CONCLUSION: H. pylori infection may be associated with development of lung cancer.