Association of the Brain-derived Neurotrophic Factor Val66Met Polymorphism with Body Mass Index, Fasting Glucose Levels and Lipid Status in Adolescents.

Brain-derived neurotrophic factor (BDNF) has an important role in energy balance. It suppresses food intake, reduces hepatic glucose production and converts white fat into brown fat in adipose tissue, leading to energy dissipation, lowered blood glucose and a lean phenotype. Studies have shown that the single nucleotide polymorphism (SNP) Val66Met within BDNF may be associated with obesity, insulin sensitivity, type 2 diabetes mellitus (T2DM) and dyslipidemia. The objective of the study was to investigate the association of the Val66Met polymorphism with body mass index (BMI), fasting glucose levels and lipid profile in Serbian adolescents. The study included 308 randomly selected healthy adolescents, 153 (49.68%) boys and 155 girls (50.32%), 15 years of age. Data including age, gender, height, weight, lipid profile and fasting glucose were recorded. Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. No association of this polymorphism was found with BMI and lipid profile. However, significant association was observed between this polymorphism and fasting blood glucose (FBG). Carriers of a Val/Val genotype had significantly higher mean values of fasting glucose level compared to carriers of Val/ Met and Met/Met genotypes (p = 0.01). To confirm these results multiple linear regression analysis was performed. Body mass index and gender were taken as covariates. Carriers of the Val/Val genotype had significantly higher levels of FBG (ß = -0.152, p = 0.02). A statistically significant association between BMI and glucose level was also observed (ß = 0.124,p = 0.033). This polymorphism could be associated with fasting glucose level in Serbian adolescents, thus further research would be of great interest to validate these results.

Multidisciplinary approach in diagnosis of lung carcinoma.

AIM: To employ multidisciplinary approach in order to make the correct diagnosis of lung carcinoma clinically and morphologically mimicking lymphoma. METHODS: Immunostaining was performed by incubating tissue sections with appropriate antibodies, using the streptavidin-biotin technique. Antigen-antibody complexes were visualized with 3-amino-9-ethylcarbasole or diaminobenzidine hydrochloride substrate solution. We have investigated p53 gene mutations by polymerase chain reaction and DNA sequence analysis of exons 5, 6, 7, 8 and 9. RESULTS: Tumor cells expressed cytokeratin AE1/AE3, epithelial membrane antigen (EMA) and thyroid transcription factor-1 (TTF-1) without thyreoglobulin positivity. Further, tumor cells expressed neuroendocrine mar kers: synaptophysin, chromogranin A, neuron-specific enolase (NSE), CD56/NCAM, CD57/Leu-7 and protein gene product 9.5 (PGP9.5). P53 was also expressed. Diffuse large cell lymphomas of B and T cell origin were excluded. Direct sequencing analysis of exon 6 of the p53 gene revealed ATC to ACC mutation at codon 195. Final diagnosis of large cell lung neuroendocrine carcinoma (LCNEC) was established. CONCLUSIONS: Morphological pattern of tumor complied with large cell non-Hodgkin's lymphoma, but large cell lung carcinoma with neuroendocrine differentiation was proved immunohistochemically and confirmed by genetic analysis of p53 mutations in tumor tissue sample. Multidisciplinary approach in diagnosis of lung carcinoma is useful for its final diagnosis.

Bcl-2 expression in oral squamous cell carcinoma.

Apoptosis is a genetically regulated process involved in tissue size regulation, morphogenesis, and elimination of genetically damaged cells. A pallet of genes is involved in the control of apoptosis, such as bcl-2 family whose oncogenic potential has been demonstrated in oral tumorigenesis. Different members of bcl-2 family may promote or inhibit apoptosis by synthesizing anti- and proapoptotic proteins. One of antiapoptotic proteins, bcl-2, with a crucial role in apoptosis regulation was the object of our study. By means of immunohistochemistry we estimated the level of overexpression of bcl-2 proteins in a series of the 26 formalin fixed, paraffin-embedded samples of oral squamous cell carcinoma (OSCC). Analyzed tumors originated from different sites of oral cavity; 7/26 belonged to stage II, 14/26 to stage III, and 5/26 to stage IV. Immunoreactivity was scored according to the percentage and intensity of positive cytoplasmic bcl-2 staining. All tumors had low percentage of positively stained bcl-2 cells, with mean values for lower/higher intensity of 8.3 +/- 2.5/34.4 +/- 7, 7.5 +/- 1.1/31.9 +/- 4.3, and 8.4 +/- 5.8/31.5 +/- 5.8 within stages II, III, and IV, respectively. Low level of bcl-2 expression in our sample seems to be associated with higher survival rate: 77% for the 5-year follow-up period. Comparing clinicopathologic and risk factors data within each and between three groups of analyzed tumors (lip-tongue P = 0.58, tongue-floor of the mouth, P = 0.21, lip-floor of the mouth, P = 0.50) there was no significant difference. However, our results suggest that the level of bcl-2 expression could be a valuable predictor of tumor behavior and disease outcome.

Modification of protein kinase pattern in human placentae during gestation.

The cAMP-dependent and cAMP-independent histone kinases have been studied in the two subcellular compartments (cytosol and particulate fraction) from placentae of different gestational age. The total protein kinase activity, as well as its distribution between the two compartments, changes during the period of gestation. The total activity is significantly increased in full-term placentae. The increase is much greater for the cAMP-dependent (400 per cent), than for the cAMP-independent (270 per cent) protein kinases. It is much higher (400 per cent) in the cytosol than in the particulate fraction (170 per cent); consequently, the particulate fraction of term placentae shows a relatively lower proportion of protein kinase activity (26 per cent of the total activity) than the corresponding fraction of young placentae (37 per cent). DEAE-cellulose chromatography revealed the presence of two cAMP-dependent protein kinase peaks which correspond to Type I and Type II isoenzymes described in many mammalian tissues (Corbin, Keely and Park, 1975). The Type II isoenzyme is predominant in both first- and third-trimester placentae. The increase in protein kinase activity in term placentae is due to the selective activation of the Type II kinase only. The activity of the Type I isoenzyme remained unchanged throughout the period of gestation. The third peak eluted from the DEAE-cellulose column corresponds to a cAMP-independent sucrose-gradient ultracentrifugation into two distinct peaks similar to those already observed in several rat tissues (Toru-Delbauffe, Ohayon and Pavlovic-Hournac, 1983). The protein kinase patterns of both young and term placentae remain stable during the incubation of the tissues 'in vitro' for three hours.