<Emphasis Type=Italic>SMAD4</Emphasis> - Molecular gladiator of the TGF-β signaling is trampled upon by mutational insufficiency in colorectal carcinoma of Kashmiri population: an analysis with relation to <Emphasis Type=Italic>KRAS</Emphasis>proto-oncogene

Background  

The development and progression of colorectal cancer has been extensively studied and the genes responsible have been well characterized. However the correlation between the SMAD4 gene mutations with KRAS mutant status has not been explored by many studies so far. Here, in this study we aimed to investigate the role of SMAD4 gene aberrations in the pathogenesis of CRC in Kashmir valley and to correlate it with various clinicopathological variables and KRAS mutant genotype.     

A comparative study of cell cycle mediator protein expression patterns in anaplastic and papillary thyroid carcinoma

Anaplastic thyroid carcinoma (ATC) is an extremely aggressive and rapidly fatal neoplasm. The aim of this study was to identify a limited cell cycle associated protein expression pattern unique to ATC and to correlate that pattern with clinical outcome. This represents one of the largest tissue micro-array projects comparing the cell cycle protein expression data of ATC to other well-differentiated tumors in the literature. Tissue microarrays were created from 21 patients with ATC and an age and gender matched cohort of patients with papillary thyroid carcinoma (PTC). Expression of epidermal growth factor receptor, cyclin D1, cyclin E, p53, p21, p16, aurora kinase A, opioid growth factor (OGF), OGF-receptor, thyroglobulin and Ki-67 was evaluated in a semi-quantitative fashion. Differences in protein expression between the cohorts were evaluated using chi-square tests with Bonferroni adjustments. Survival time and presence of metastasis at presentation were collected. The ATC cohort showed a statistically significant decrease (p < 0.05) in thyroglobulin expression and statistically significant increases (p < 0.05) in Ki-67 and p53 expression as compared with the PTC cohort. A trend toward loss of p16 and p21 expression was noted in the ATC cohort. A trend toward decreased survival was noted with p21 expression. These data indicate disruption of the normal cell cycle with aberrant expression of multiple protein markers suggesting increased proliferative activity and loss of control of cell cycle progression to G? phase. These findings support the assertion that ATC may represent the furthest end of a continuum of thyroid carcinoma dedifferentiation.     

Association of cyclin D1 gene polymorphisms with risk of esophageal squamous cell carcinoma in Kashmir Valley: a high risk area

Investigation of potential association of SNPs (G870A, rs9344; G1722C, rs678653) of cyclin D1 gene (CCND1) with susceptibility to esophageal squamous cell carcinoma (ESCC) in Kashmir valley (India). The study included 302 subjects comprising 151 ESCC cases and 151 controls. PCR‐RFLP and direct sequencing were employed for genotyping. The G870A polymorphism, the individuals carrying GA + AA genotype was having 2.80‐fold increased risk for development of ESCC (OR 2.8, 95% CI = 1.77–4.4; P = 0.0001) compared to GG genotype. Further a significantly higher risk was observed in individuals who consume >3 cups per day of salted tea (OR = 5.1; 95% CI = 1.6–16.7; P = 0.0016) and had smoking habits (OR = 6.3; 95% CI = 2.9–13.9; P = 0.0005). We also demonstrate for the first time in CCND1 1722 locus, the CC genotype was strongly associated with increased risk of developing ESCC (OR = 2.58; 95% CI = 1.61–4.15; P = 0.0001). In addition, the frequency of polymorphic C allele was also found to be higher in cases (OR = 1.92; 95% CI = 1.37–2.69; P = 0.0002). There appears to be an influence of CCND1 G870A/G1772C genotypes on genetic susceptibility to ESCC. Mol. Carcinog. ©2011 Wiley‐Liss, Inc.     

Effect of lacosamide on ethanol induced conditioned place preference and withdrawal associated behavior in mice: Possible contribution of hippocampal CRMP-2

BackgroundExcessive consumption of ethanol is known to activate the mTORC1 pathway and to enhance the Collapsin Response Mediator Protein-2 (CRMP-2) levels in the limbic region of brain. The latter helps in forming microtubule assembly that is linked to drug taking or addiction-like behavior in rodents. Therefore, in this study, we investigated the effect of lacosamide, an antiepileptic drug and a known CRMP-2 inhibitor, which binds to CRMP-2 and inhibits the formation of microtubule assembly, on ethanol-induced conditioned place preference (CPP) in mice.MethodsThe behavior of mice following ethanol addiction and withdrawal was assessed by performing different behavioral paradigms. Mice underwent ethanol-induced CPP training with alternate dose of ethanol (2 g/kg, po) and saline (10 ml/kg, po). The effect of lacosamide on the expression of ethanol-induced CPP and on ethanol withdrawal associated anxiety and depression-like behavior was evaluated. The effect of drug on locomotor activity was also assessed and hippocampal CRMP-2 levels were measured.ResultsEthanol-induced CPP was associated with enhanced CRMP-2 levels in the hippocampus. Lacosamide significantly reduced the expression of ethanol-induced CPP and alleviated the levels of hippocampal CRMP-2 but aggravated withdrawal-associated anxiety and depression in mice.ConclusionThe present study demonstrated the beneficial effect of lacosamide in attenuation of expression of ethanol induced conditioned place preference via reduction of hippocampal CRMP-2 level. These findings suggest that lacosamide may be investigated further for ethanol addiction but not for managing withdrawal.     

Carbapenem-resistant Escherichia coli and Klebsiella pneumoniae isolates from Turkey with OXA-48-like carbapenemases and outer membrane protein loss

Treatment options are limited in infections caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, with carbapenems generally preferred. Disturbingly, however, carbapenem-resistant strains are emerging worldwide. Here we report two clinical isolates, one Escherichia coli and one Klebsiella pneumoniae, each with high-level carbapenem resistance (imipenem minimum inhibitory concentration of 32 microg/mL). They were isolated following imipenem therapy from two hospital patients who had received imipenem therapy in different regions of Turkey. Both isolates produced OXA-48-like carbapenemases, enzymes so far reported only from Turkey. Both isolates also had group 1 CTX-M-type ESBLs and had lost major outer membrane proteins. OXA-48-like carbapenemases appear to be scattered in Turkey and surveillance to determine their prevalence is warranted.     

Effect of Di-(2-ethylhexyl) Phthalate on Rat Liver Injured by Chronic Carbon Tetrachloride Treatment

Abstract The effect of Di-(2-ethylhexyl) phthalate (DEHP), a widely used plasticizer, was studied using histopathological and biochemical parameters on rat liver injured by carbon tetrachloride (CCl₄). The mild centrilobular necrosis observed with CCl₄ (7.7 mmol/kg subcutaneously and biweekly up to 38 days) and mild congestion and bile duct proliferation produced by DEHP (2.5 mmol/kg intraperitoneally daily for ten days after the day 28 of experiment) were modified into extensive necrosis of the parenchymal cells when the animals received both chemicals. Groups of hepatocytes mostly at the periphery of the lobules also showed coagulative necrosis and some central and portal veins were completely occluded. Alterations in the activity of serum and liver enzymes of the animals receiving both chemicals were not significantly different from those treated with CCL alone, except in case of glucose-6-phosphatase (G-6-Pase) and SGPT. The characteristic decrease of G-6-Pase and increase of SGPT was less marked. Although the exact mechanism of the chemical interaction between CCl₄ and DEHP is not known, the results indicate their combined toxic potentiality.     

Eukaryotic arylamine N-acetyltransferase. Investigation of substrate specificity by high-throughput screening

Arylamine N-acetyltransferases (NAT; EC 2.3.1.5) catalyse the transfer of acetyl groups from acetylCoA to xenobiotics, including drugs and carcinogens. The enzyme is found extensively in both eukaryotes and prokaryotes, yet the endogenous roles of NATs are still unclear. In order to study the properties of eukaryotic NATs, high-throughput substrate and inhibitor screens have been developed using pure soluble recombinant Syrian hamster NAT2 (shNAT2) protein. The assay can be used with a wide range of compounds and was used to determine substrate specificity of shNAT2. We describe the expression and characterisation of shNAT2 and also purified recombinant human NAT1 and NAT2, including the use of the assay to explore the substrate specificities of each of the enzymes. Hamster NAT2 has similar substrate specificity to human NAT1, acetylating para-aminobenzoate but not arylhydrazine and hydralazine compounds. The overlapping but distinct substrate-specific activity profiles of human NAT1 and NAT2 were clearly observed from the screen. Naturally occurring compounds were tested as substrates or inhibitors of shNAT2 and succinylCoA was found to be a potent inhibitor of shNAT2.     

Comparison of analgesic effects of nimesulide, paracetamol, and their combination in animal models

Objectives:

To compare the analgesic activity of nimesulide and paracetamol alone and their combination in animal models for the degree of analgesia and the time course of action.

Materials and Methods:

Analgesia was studied in albino rats using formalin test and in albino mice using writhing test and the radiant heat method. For each test, four groups of six animals each were orally fed with a single dose of nimesulide, paracetamol, and combination of nimesulide + paracetamol and gum acacia as control, respectively.

Results:

In all the three test models, all three drug treatments showed significant analgesia (P < 0.001) as compared to control, but there was no significant difference in the analgesia produced by either drugs alone or in combination. The radiant heat method demonstrated a quicker onset and longer duration of action with nimesulide, whereas writhing test showed a quicker onset of action with paracetamol. In formalin test, greater degree of analgesia was seen with individual drugs than that of the combination, though this difference was not statistically significant.

Conclusions:

Nimesulide and paracetamol combination offers no advantage over nimesulide alone or paracetamol alone, either in terms of degree of analgesia or onset of action. Therefore, our study supports the reports claiming irrationality of the fixed dose combination of nimesulide and paracetamol.     

DFNB79: reincarnation of a nonsyndromic deafness locus on chromosome 9q34.3

Genetic analysis of an inbred Pakistani family PKDF280, segregating prelingual severe to profound sensorineural hearing loss, provided evidence for a DFNB locus on human chromosome 9q34.3. Co-segregation of the deafness trait with marker D9SH159 was determined by a two-point linkage analysis (LOD score 9.43 at θ=0). Two additional large families, PKDF517 and PKDF741, co-segregate recessive deafness with markers linked to the same interval. Haplotype analyses of these three families refined the interval to 3.84 Mb defined by D9S1818 (centromeric) and D9SH6 (telomeric). This interval overlaps with the previously reported DFNB33 locus whose chromosomal map position has been recently revised and assigned to a new position on chromosome 10p11.23–q21.1. The nonsyndromic deafness locus on chromosome 9q segregating in family PKDF280 was designated DFNB79. We are currently screening the 113 candidate DFNB79 genes for mutations and have excluded CACNA1B, EDF1, PTGDS, EHMT1, QSOX2, NOTCH1, MIR126 and MIR602.