Probodh Borah

Naringenin ameliorates inflammation and cell proliferation in benzo(a)pyrene induced pulmonary carcinogenesis by modulating CYP1A1, NFκB and PCNA expression

Lung cancer is the major cause of cancer-related mortality and is a growing economic burden worldwide. Chemoprevention has emerged as a very effective preventive measure against carcinogenesis and several bioactive compounds in diet have shown their cancer curative potential on lung cancer. Naringenin (NRG), a predominant flavanone found in citrus fruits has been reported to possess anti-oxidative, anti-inflammatory and anti-proliferative activity in a wide variety of cancer. The aim of the present study is to divulge the chemopreventive nature of NRG against benzo(a)pyrene (B[a]P) induced lung carcinogenesis in Swiss albino mice. Administration of B[a]P (50mg/kg, p.o.) to mice resulted in increased lipid peroxidation (LPO), proinflammatory cytokines (TNF-α, IL-6 and IL-1β) with subsequent decrease in activities of tissue enzymic antioxidants (SOD, CAT, GPx, GR, GST) and non-enzymic antioxidants (GSH and Vit-C). Treatment with NRG (50mg/kg body weight) significantly counteracted all these alterations thereby showing potent anti-cancer effect in lung cancer. Moreover, assessment of protein expression by immunoblotting and mRNA expression by RT-PCR revealed that NRG treatment effectively negates B[a]P-induced upregulated expression of CYP1A1, PCNA and NF-κB. Further, the antiproliferative effect of NRG was confirmed by histopathological analysis and PCNA immunostaining in B[a]P induced mice which showed increased PCNA expression that was restored upon NRG administration. Overall, these findings substantiate the chemopreventive potential of NRG against chemically induced lung cancer in mice.

Poly (ADP-ribose) polymerase-1 inhibitor, 3-aminobenzamide pretreatment ameliorates lipopolysaccharide-induced neurobehavioral and neurochemical anomalies in mice.

Poly (ADP-ribose) polymerase-1 (PARP-1) functions at the center of cellular stress and sways the immune system at several key points, thus modulates inflammatory diseases. The antiinflammatory properties of PARP-1 inhibitors have been demonstrated ameliorating effect in various neuroinflammatory disorders. It has been reported that there is a close relationship between the inflammatory processes and major depressive disorder. In the present study, we have elucidated the role of oxidative-nitrosative stress-PARP-1 pathway in lipopolysaccharide (LPS)-induced neurobehavioral and neurochemical alterations in mice. 3-Aminobenzamide (10 and 30mg/kg) and imipramine (10 and 30mg/kg) were administered once daily for 14days. Mice were challenged with LPS (1mg/kg, i.p.) 30min after drug administration on the 14th day. The mRNA expression level of PARP-1 (12h after LPS injection) in the hippocampus was measured through quantitative real-time PCR. All the behavioral and biochemical parameters were assessed at 24h after LPS injection. The expression level of PARP-1mRNA was found significantly up-regulated in the hippocampus at 12h after LPS administration. Results showed that the LPS-challenged mice exhibited an increase in immobility time seen in forced swimming test and tail suspension test. LPS increased the levels of proinflammatory cytokines and oxido-nitrosative stress parameters in the hippocampus. However, pretreatment with 3-aminobenzamide (30mg/kg) significantly reversed the LPS-induced alterations in behavioral parameters, proinflammatory cytokines, oxidative-nitrosative stress and PARP-1 mRNA levels. Imipramine failed to prevent the up-regulation of PARP-1 induced by LPS administration. Our results emphasized that oxidative-nitrosative stress-PARP-1 cascade can play a key role in LPS-induced neurobehavioral and neurochemical anomalies.

Isolation and characterization of Clostridium difficile from pet dogs in Assam, India.

One hundred and seventeen faecal samples from pet dogs (pup = 21 and adult = 96) brought for treatment to a veterinary clinic were examined for Clostridium difficile. A total of 16 (13.67%) samples were positive. Nine (56.25%) isolates were obtained from 17 adult dogs undergoing antibiotic treatment and this was significantly higher (p < 0.01) as compared to isolates from dogs without antibiotic treatment. Ten isolates (62.5%) were toxigenic (all toxinotype 0) and six were non-toxigenic. None of the isolates were positive for binary toxin genes. PCR ribotyping revealed three different ribotypes (012, 014 and 046) among A(+)B(+) isolates and five different ribotypes (010, SLO 131, and ACD 001 to ACD 003) among A(-)B(-) isolates. The PFGE analysis of toxigenic isolates revealed three different pulsotypes corresponding to the PCR ribotypes.

Isolation and characterization of Shiga toxigenic Escherichia coli of animal and bird origin by multiplex polymerase chain reaction

Aim: The purpose of this study was to determine the virulence genes and serotype of Shiga toxin producing Escherichia coli (STEC) strains isolated from animals and birds. Materials and Methods: A total of 226 different samples viz., fecal, intestinal content, rectal swab and heart blood were collected from different clinically affected/healthy animals and birds and were streaked on McConkeys’ lactose agar and eosin methylene blue agar for isolation of E. coli, confirmed by staining characteristics and biochemical tests. By polymerase chain reaction (PCR) all the E. coli isolates were screened for certain virulence genes, viz., Shiga toxin 1 (stx1), stx2 and eae and enterohemolytic (Ehly) phenotype was observed in washed sheep blood agar plate. All the isolated E. coli strains were forwarded to the National Salmonella and Escherichia Centre, Central Research Institute, Kasauli (Himachal Pradesh) for serotyping. Results: Out of 226 samples 138 yielded E. coli. All the isolates were screened for molecular detection of different virulent genes, viz. stx1, stx2 and eae, based on which 36 (26.08%) were identified as STEC. Among those STEC isolates, 15 (41.67%), 14 (38.89%), 1 (2.78%) exhibited eae, stx2, stx1 alone, respectively, whereas 4 (11.11%) and 2 (5.56%) carried both stx1 and stx2, stx2 and eae, respectively. Among the STEC isolates 22 were belonged to 15 different sero-groups, viz., O2, O20, O22, O25, O43, O60, O69, O90, O91, O95, O106, O118, O130, O162 and O170 and others were untypable. Ehly phenotype was observed in 10 (27.78%) the STEC isolates. Conclusion: The present study concluded that STEC could be isolated from both clinically affected as well as healthy animals and birds. Regular monitoring of more samples from animal and bird origin is important to identify natural reservoir of STEC to prevent zoonotic infection.

Single nucleotide polymorphisms of APOA1 gene and their relationship with serum apolipoprotein A-I concentrations in the native population of Assam.

Background There is a growing interest in the role of allelic variants of the APOA1 gene in relation to a number of disorders. We described two common polymorphisms of the APOA1 gene, G-75A and C+83T and investigated their potential influence on the serum apolipoprotein A-I (apo A-I) levels in the native population of Assam — a region that is ethnically distinct and from where no information is hitherto available. Methods Blood samples were collected from 150 healthy volunteers. Apo A-I levels were estimated by immunoturbidometry. Genotyping was done by a PCR-RFLP method that involved DNA extraction from whole blood, followed by polymerase chain reaction and digestion of the PCR product by MspI restriction enzyme, and analysis of fragment sizes in 12% polyacrylamide gel. Results The GG variant at G-75A locus and CC variant at C+83T locus were the most prevalent. GG/CC was the most common combination. Homozygous TT genotype was not detected in any of the subjects. The rare allele frequencies for the G-75A and C+83T sites were found to be 0.22 and 0.06 respectively, which significantly differed from those reported in some other populations in neighbouring regions. Serum apo A-I concentrations did not vary significantly across the detected genotypes. These findings were consistent in both sexes. Conclusion We described the distribution of the G-75A and C+83T polymorphisms of the APOA1 gene in the population of Assam for the first time. These polymorphisms were not found to directly influence apo A-I concentrations in this population either individually or synergistically.

Variation in Lipid Profile Across Different Patterns of Obesity - Observations from Guwahati, Assam.

BACKGROUND Obesity adversely affects cardiovascular health is known. But, data is few in this regard from Assam, northeast India. The serum lipid profile is performed for cardio-metabolic status assessment. AIM The aim of the study was to investigate variation in serum lipids across different obesity patterns in an urban population from Assam. MATERIALS AND METHODS Two hundred subjects were classified by WC (waist circumference) and BMI (body mass index) values into four groups as follows: Group I (normal WC, normal BMI), Group II (normal WC, increased BMI), Group III (increased WC, normal BMI) and Group IV (increased WC, increased BMI). WC and BMI served as measures of central and generalized obesity respectively. Lipid profile was measured using VITROS 5600 Autoanalyser, and compared across these groups. Multivariate analyses were performed separately for males and females to confirm the results of univariate analyses. RESULTS WC and BMI exhibited significant correlations with different lipid parameters. Group IV individuals had the most abnormal lipid profile values, while, Group I individuals had the most normal values. Group II and Group III individuals had intermediate values. BMI was independently associated with serum triglycerides in both males and females. WC was independently associated with high density lipoprotein cholesterol in females. CONCLUSION The lipid values varied significantly across different obesity patterns. Serum lipid concentrations were strongly influenced by anthropometric indices of obesity in both sexes. Presence of both central and generalized obesity led to greater abnormalities in lipid profile than presence of central or generalized obesity alone.

Association of Decreased High-Density Lipoprotein Cholesterol (HDL-C) With Obesity and Risk Estimates for Decreased HDL-C Attributable to Obesity: Preliminary Findings From a Hospital-Based Study in a City From Northeast India.

Background: Obesity is an important risk factor for decrease in high-density lipoprotein cholesterol (HDL-C) levels, which predisposes to cardiovascular diseases. But, the relative contribution of obesity toward decreased HDL-C and the risk estimates of decreased HDL-C attributable to obesity are unavailable. Such measures will help in understanding the extent by which the burden of decreased HDL-C can be reduced by tackling obesity. Objectives: The objectives of this study were to (a) determine the association between decreased HDL-C and obesity and (b) estimate the attributable risk proportion (ARP) and population attributable risk proportion (PARP) for decreased HDL-C due to obesity. Methods: Body mass index (BMI) and waist circumference (WC) were measured as indices of overweight (or generalized obesity) and central obesity, respectively in 190 subjects (95 cases with low HDL-C and 95 healthy controls with normal HDL-C) from Guwahati city. Crude odds ratio (OR) and adjusted OR with 95% confidence interval (CI) were calculated along with the risk estimates (ARP and PARP). Results: People with overweight or generlized obesity (adjusted OR = 4.90, 95% CI = 3.59-6.68), and people with central obesity (adjusted OR = 3.33, 95% CI = 2.39-4.64) had significantly greater odds of developing decreased HDL-C. Among the exposed, 79.8% of the decreased HDL-C cases could be attributed to overweight (or generalized obesity), while 72.8% cases could be attributed to central obesity. In the overall population, the corresponding figures were 57.1% and 36%, respectively. Conclusion: Decreased HDL-C is strongly associated with and largely attributable to obesity.

Association of the Apolipoprotein A-I gene polymorphisms with cardiovascular disease risk factors and atherogenic indices in patients from assam, Northeast India

Abstract Cardiovascular disease (CVD) risk factors, and particularly decreased high density lipoprotein cholesterol (HDL-C) dyslipidemia are prevalent in Assam, India. This study was undertaken to investigate whether Apolipoprotein A-I (APOA1) gene polymorphisms (G-75A and C+83T) were associated with i) the risk for decreased HDL-C, and ii) other CVD risk factors, viz. serum lipids, atherogenic indices, obesity, and blood pressure (BP). A total of 649 subjects were screened, from which 200 eligible individuals, classified as case group with decreased HDL-C levels (100 subjects) and control group with normal HDL-C levels (100 subjects) were enrolled and genotyped using polymersase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. Lipid fractions [HDL-C, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), triglycerides (TG)] and atherogenic indices [Castelli’s Risk Indices-I and -II (CRI-I and -II), non-HDL-C fraction, atherogenic index of plasma (AIP), atherogenic coefficient (AC)] were estimated. The G-75A and C+83T loci were not associated with decreased HDL-C risk. This was confirmed across different genetic models (dominant, recessive, additive and allelic). Association was also absent with BP and obesity. However, the G-75A locus was associated with LDL-C, whereas the C+83T locus was associated with TG and VLDL-C. Furthermore, these sites had effects on atherogenic indices. The rare A allele at the G-75A locus was associated with adverse CRI-I, CRI-II, non-HDL-C and AC values, while the major C allele at the C+83T locus was associated with adverse AIP values. Thus, the pro-atherogenic G-75A polymorphism and the anti-atherogenic C+83T polymorphism represent important genetic loci that modulate CVD risk factors in subjects from Assam.

Identification of swinepox virus from natural outbreaks in pig population of Assam

Outbreaks of swinepox [caused by a swinepox virus (SWPV)] in pigs were investigated in 3 districts of Assam, a north eastern state of India. Diagnosis of the disease was carried out employing both standard virological as well as molecular methods. Three representative isolates from different places were selected for inoculation into confluent monolayers of Porcine Kidney-15 (PK-15) cell line. The cytopathic effects were characterized by cell rounding, nuclear vacuolation, cell fusion, granulation of cells and finally detachment from third blind passage onwards. The three genes viz., SPV18–20 and P42 of SWPV was targeted for confirmation of the virus. Swinepox virus was successfully adapted to the PK-15 cell line from seventh passage onwards. The isolated viruses were characterized by sequencing and phylogenetic analysis of P42 gene (extracellular envelope protein), a homologue of vaccinia virus F13L gene. In India, studies on swine pox are very limited. This is the first report on successful isolation of swinepox virus from north eastern region of India. Assam and the other north-eastern states of India being a hub for pig husbandry, isolation of swinepox virus will help in developing and formulating control strategies against the disease.

Are internet videos useful sources of information during global public health emergencies? A case study of YouTube videos during the 2015–16 Zika virus pandemic

ABSTRACT Background: Internet-videos, though popular sources of public health information, are often unverified and anecdotal. We critically evaluated YouTube videos about Zika virus available during the recent Zika pandemic. Methods: Hundred-and-one videos were retrieved from YouTube (search term: zika virus). Based upon content, they were classified as: informative, misleading or personal experience videos. Quality and reliability of these videos were evaluated using standardized tools. The viewer interaction metrics (e.g. no. of views, shares, etc.), video characteristics (video length, etc.) and the sources of upload were also assessed; and their relationship with the type, quality and reliability of the videos analyzed. Results: Overall, 70.3% videos were informative, while 23.8% and 5.9% videos were misleading and related to personal experiences, respectively. Although with shorter lengths (P < 0.01) and superior quality (P < 0.01), yet informative videos were viewed (P = 0.054), liked (P < 0.01) and shared (P < 0.05) less often than their misleading counterparts. Videos from independent users were more likely to be misleading (adjusted OR = 6.48, 95% CI: 1.69 – 24.83), of poorer (P < 0.05) quality and reliability than government/news agency videos. Conclusion: A considerable chunk of the videos were misleading. They were more popular (than informative videos) and could potentially spread misinformation. Videos from trustworthy sources like university/health organizations were scarce. Curation/authentication of health information in online video platforms (like YouTube) is necessary. We discuss means to harness them as useful source of information and highlight measures to curb dissemination of misinformation during public health emergencies.