Prevalence and Covariates of Undiagnosed Hypertension in the Adult Population of Puducherry, South India

Background Globally the prevalence of both hypertension and pre-hypertension are increasing and pre-hypertension has been associated with higher cardiovascular risk. The objective of this study was to find out the prevalence of undiagnosed hypertension and pre-hypertension and associated covariates among adults of rural and urban area of Puducherry. Material and Methods A population based cross-sectional study was carried out in the field practices area of Department of Community Medicine, Mahatma Gandhi Medical College and Research Institute without intervention. Results Among 856 participants, 27.6 percent were hypertensive and 57 percent pre-hypertensive; the magnitude of both stage 1 and stage 2 hypertension increased with the age. Of the hypertensives, 26.3 and 28.7 percent were from rural and urban area respectively, whereas in pre-hypertension the corresponding figures were 61 and 53.4 percent.  Significantly increased risk of hypertension was noted among adults with increasing age, having less than six members in the family, suffering from obesity (general and abdominal obesity) and living sedentary life. On the other hand, the probability of having increased risk of pre-hypertension was significantly higher among adults living in the rural areas, having non-vegetarian dietary habit, suffering from obesity (general and abdominal obesity), living sedentary life and having family history of hypertension. Multivariate logistic regression however showed significant correlation of hypertension with increasing age, sedentary lifestyle, tobacco addiction and obesity (general and central). Significant correlates of pre-hypertensive were rural residence, sedentary living habits, family history of hypertension, tobacco addiction and obesity (general and central). Conclusion The present findings show high prevalence of hypertension and pre-hypertension among population of Puducherry in South India.DOI: http://dx.doi.org/10.3126/nje.v2i2.6576 Nepal Journal of Epidemiology 2012;2(2):191-199

P4-05-04: Arachidonic Acid-Induced Elevated Expression of 5-Lipoxygenase Is Linked to Metastatic Migration of Breast Cancer Cells

Background: In invasive breast cancers, cancerous cells spread outside the ducts of the breast and metastasize to lung and other tissues. Although the rapid arachidonic acid (AA) metabolism and concomitant increase of eicosanoid molecules are involved in the proliferation and invasion of breast cancer cells, the exact mechanism by which AA metabolites regulate these phenomena are not well understood. Here, we show that leukotriene B4 (LTB4), one of the metabolites of AA, which is produced by the action of 5-lipoxygenase (5-LOX), causes the proliferation and metastatic migration of breast cancer cells.

Material and Methods: MDA-MB-231 (invasive breast cancer cells) and MCF7 (non-invasive breast cancer cells) were used in this study. Briefly, cells were treated with AA (100 μM) and nordihydroguaiarectin acid (NDGA, 10 μM), and the secreted eicosanoids were characterized by HPLC. Immunofluorescence microscopy was performed to elucidate the expression and intracellular localization of 5-LOX. The metastatic migration was analyzed by wound-healing assays.

Results: Our results suggest that while MDA-MB-231 cells produce high levels of PGE2 and PGD2, MCF7 cells synthesize excess HETE compounds (HETE5 and HETE8). Interestingly, MDA-MB-231 cells, when stimulated with AA, show the increased syntheses of LTB4 (∼3 fold) and decreased PGE2 and PGD2 (∼2 fold). In MCF7, on the contrary, AA treatment reduced the syntheses of all eicosanoids. Furthermore, the expression of 5-LOX in MDA-MB-231 cells was also increased by ∼2 fold. We observed that AA promotes cell migration in MDA-MB-231 cells, which could be blocked by NDGA, a generic inhibitor of LOX enzymes. Because LTB4 production and its binding with BLT receptors are linked to IL-8 secretion, we measured the level of IL-8 synthesized by both MCF7 and MDA-MB-231 cells. The results suggest that MDA-MB-231 cells secrete excess IL-8 (∼2 fold) when stimulated with AA, suggesting that LTB4 and IL-8 interactive pathways are important for cancer metastasis.

Discussion: Our results demonstrate that LTB4 synthesis is linked to the metastatic migration of MDA-MB-231 cells, and that it therefore should be considered as a target for developing new drugs for the treatment of invasive breast cancers.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-05-04.

Distribution profile of paraoxonase phenotypes among the Gujaratis

BACKGROUND:

Paraoxonase (PON1) can hydrolyze organophosphate pesticides (OP) and has a key role in the susceptibility of human in OP toxicity. The human-enzyme shows polymorphism and variations in the distribution profile of its phenotypes among different ethnic groups have been observed.

AIMS:

To see the distribution pattern of total PON1 activity in 45 healthy attendants of poisoning cases; 121 healthy unrelated farm-labours and 59 normal subjects of trauma.

MATERIALS AND METHODS:

The PON1 activities from serum/plasma samples of these healthy normal individuals were estimated with/without addition of 1M NaCl in order to determine salt-stimulated and basal activity. The PON 1 phenotypes were determined on the basis of percent activation of enzyme activity.

RESULTS:

Tri-modal distribution of basal PON1 activity was observed among all these individuals. 52.0% of the individuals belonged to Phenotype A, 46.6% to phenotype AB while 1.4% to Phenotype B with gene frequency of allele-A and allele-B being 0.753 and 0.247 respectively in excellent agreement with Hardy-Weinberg equilibrium.

CONCLUSION:

Maximum number of individuals belonged to phenotype-A (low PON1 activity) showing potential vulnerability towards Op-poisoning.

Correlates of cervical cancer screening among underserved women

BACKGROUND AND OBJECTIVES

Substantial subgroups of Indian women, specifically those of ethnic minorities, had not been screened for cervical cancer or are not screened at regular intervals. We aim to find out the magnitude of cervical cancer and precancerous lesions among women in the age group 15-60 years, and to identify the various socio-demographic and reproductive correlates among those with the cervical lesions.

PATIENTS AND METHODS

Nine hundred and sixty-eight adult women in the age group 15-60 years were selected by simple random sampling technique in a population based descriptive cross-sectional study in a cervical cancer screening camp in a primary health center at the East Sikkim, during 1st September to 30th November 2006. Main outcome measures were the extent and correlates of cervical cancer without any interventions. The data collection tool used for the study was a pre-tested questionnaire prepared prior to the study for ensuring feasibility, acceptability, time management, validity and reliability. Information on socio-demographic and reproductive variables was collected by interview method using this questionnaire.

RESULTS

Out of 968 women in the study population, overwhelming majority 921 (95.15%) had no overt or pre-cancerous cervical lesion. Only 47 were found to have changes in their cervical epithelium. None of these 47 women was proved dyskaryotic on cytopathological screening of the cervical smear. No significant difference was noted among those with or without lesions among women below 30 years of age with those above, among illiterate women with literates, in per capita monthly family income difference, age at marriage and childbirth. Low-grade and high-grade squamous intraepithelial cervical lesions were associated with Hindu women only and were related with past history of abortion and still birth in women significantly.

CONCLUSION

There was an imperative need for identifying prevalence of asymptomatic cervical dysplasia in all population.

Hepatoprotection by carotenoids in isoniazid–rifampicin induced hepatic injury in rats

This study evaluates the hepatoprotective effect of carotenoids against isoniazid (INH) and rifampicin (RIF). Thirty-six adult rats were divided into the following 4 groups: (1) control group treated with normal saline; (2) INH + RIF group treated with 50 mg·(kg body mass)–1·day–1 of INH and RIF each; (3) INH + RIF+ carotenoids group treated with 50 mg·(kg body mass)–1·day–1 of INH and RIF each and 10 mg·(kg body mass)–1·day–1 of carotenoids; and (4) carotenoids group treated with 10 mg·(kg body mass)–1·day–1 of carotenoids for 28 days intragastrically. Oxidative stress and antioxidant levels in liver and blood, liver histology and change in transaminases were measured in all the above-mentioned groups. There was an increase in lipid peroxidation with a reduction in thiols, catalase, and superoxide dismutase (SOD) in the liver and blood of rats accompanied by an increase in transaminases, bilirubin, and alkaline phosphatase. Treatment with carotenoids along with INH + RIF partially reversed lipid peroxidation, thiols, catalase, and SOD in the liver and blood of rats. Elevated levels of the enzymes in serum were also reversed partially by this treatment. The degree of necrosis, portal triaditis, and inflammation were also lowered in the carotenoids group. In conclusion, carotenoids supplementation in INH + RIF treated rats showed partial protection.

Development of a Pedal Powered Wheelchair

A first student project to put pedals on a wheelchair for exercise and propulsion was unsuccessful. The need remained and in June of 2005 the “Eureka” event occurred. Seeing a five-year-old on her training-wheel-equipped bicycle suggested that a fifth wheel could be added in the center between the wheelchair's two large rear wheels, and a mast supported by the fifth wheel's axle could extend forward to support a front axle and pedal set. A chain drive completed the propulsion system. There are no pedal-powered wheelchairs currently on the market. Around 2001 a product (EZChair) without retractable pedals was on the market but withdrawn. A team at the University of Buffalo invented and patented a pedal-powered wheelchair in 1993 (US Patent 5,242,179), but it was not commercialized. Also, a Japanese company designed and built a series of fifth-wheel wheelchair designs. Between 2006 and late 2008 we built many prototypes incorporating geometries that permitted retracting the pedal. For compactness a “Pedalong” with three telescoping tubes was built but it proved impossible to secure tightly. In the next design twin telescoping tubes passing above and to the rear of the rear axle provided the desired extension. A clamp at the front of the outer tube provided tightness of the assembly. In the Northwestern research program (see below), there was some success, but awkwardness in operation prevented commercialization. In October 2008 a major design change from a fifth wheel in the center to a powering of the two standard rear wheels was begun. This required a new chain path geometry and addition of a differential to the drive train. With the new design user control, arm-powering and braking through the rear wheels is retained, and chair stability is improved. Twelve individuals with chronic post-stroke hemiplegia (>6 months post-stroke event) participated in a study to examine the metabolic energy expended when participants performed a 6-minute walk test, a 6 minute leg-propelled wheelchair trial (using the Pedalong), and a 6 minute arm-propelled wheelchair trial. VO2, VCO2, and distance traveled were measured using a portable metablic cart system and wheel-based distance measurement system. The Pedalong and walking trials showed equivalent oxygen consumption levels, but manual pushing was, on average, significantly less. All three modes (walking, leg-propelled and arm-propelled) resulting in similar distances traveled within the 6 minute period. The leg-propelled trials generated the greatest amount of VCO2 during expiration compared with the other modes. This means that more of the available oxygen is being utilized (metabolized) during the leg-propelled mode and so, a greater number of calories were being burned during this 6-minute test.

Orocecal transit time in patients in the chronic phase of corrosive injury

Accidental/suicidal ingestion of corrosive substances is common in North India. Decreased gastric secretion and delayed gastric emptying in the chronic phase of corrosive injury has been documented at our center. We hypothesize that patients in the chronic phase of corrosive injury may have delayed orocecal transit time (OCTT).

OBJECTIVE

To measure the orocecal transit time (using the noninvasive method of lactulose hydrogen breath test) in patients in the chronic phase of corrosive injury.

METHODS

Thirty patients with corrosive injury to their gastrointestinal tract with its sequelae and attending the gastroenterology services of PGIMER, Chandigarh for endoscopic dilatation of strictures were enrolled in this study. Patients with age >60 years, vagotomy, prior gastric surgery, peptic ulcer disease, systemic sclerosis, history of diabetes, hypothyroidism or intestinal pseudo-obstruction were excluded. Orocecal transit time was measured by using a 15 mL lactulose hydrogen breath test. End expiratory breath was taken every 10 min until there was a rise >10 ppm over the fasting value in two consecutive readings.

RESULTS

Thirty patients (11 females and 19 males) with a median age of 32 years, 27 with acid ingestion and 3 with alkali ingestion, were studied. None had symptoms of gastric outlet obstruction or gastroparesis. OCTT was significantly prolonged in the study group as compared to the control group (135.4 +/- 15.8 versus 90.6 +/- 10.4 min). No significant difference was observed between different age groups, gender, and type of caustic agent consumed. OCTT was maximally prolonged in patients with involvement of lower oesophagus, whereas patients without lower oesophagus involvement did not show significantly altered OCTT.

CONCLUSION

Our results show that patients with corrosive injury have prolonged OCTT even in the absence of any gastric symptoms. OCTT was prolonged maximally in patients with lower-third oesophageal cicatrization. This may a result of autovagotomy due to vagal entrapment in the cicatrization process involving the lower third of oesophagus.

Isoniazid-rifampicin induced lipid changes in rats

INTRODUCTION

Isoniazid (INH) and rifampicine (RIF) continues to be highly effective drugs in the chemoprophylaxis and treatment of tuberculosis. It is associated with hepatotoxicity in some individuals. Change in liver and serum lipids may be one of the reasons of hepatotoxicity. We examined isoniazid-rifampicine induced lipid changes in liver and serum of rats.

METHODS

In a rat model of INH-RIF induced hepatotoxicity we evaluated the effect of oral administration of INH-RIF (50 mg/kg body weight /day each) on hepatic marker enzymes, total lipids, cholesterol, triglycerides and phospholipids in serum and liver of experimental rats after 28 days. Enzymes, total lipids and lipid fractions were measured according to standard methods.

RESULTS

Treatment with INH-RIF increased the hepatic marker enzymes after 28 days and altered the lipid levels in serum and liver. Administration of INH-RIF resulted in significantly increased liver and serum cholesterol and total Lipids as compared to control group, while triglycerides were significantly elevated in liver only. In contrast, phospholipids were significantly decreased in liver and no effect in serum was observed.

CONCLUSION

Changes in lipids (both in serum and liver) are likely involved in the pathogenesis of INH-RIF induced hepatoxicity in rats.

Standardization and stability studies of neuroprotective lipid soluble fraction obtained from Curcuma longa

The lipid soluble fraction of curcuma longa, i.e. herbal medicament (HM) was isolated from rhizome of curcuma longa by solvent extraction method. The identification of chemical constituent present in HM was done with GC, GC-MS. The standardization of HM was done using HPLC method on the basis of three-marker compound isolated, i.e. ar-turmerone, turmerone and curlone. The effect of temperature, pH and light on stability of marker compounds of HM was studied. The composition of marker compound in HM was found to be 50-60%. The content of curcumnoids, another bioactive constituent present in HM was found to be 0.32-0.55%. The HM was found to be stable at different temperature and pH but light sensitive.

Comparison of D-xylose hydrogen breath test with urinary D-xylose test in Indian children with celiac disease

D-xylose hydrogen breath test (H2BT) may be better parameter in screening for intestinal malabsorption in patients with celiac disease. This study sought to compare D-xylose H2BT with urinary D-xylose tests in screening for intestinal malabsorption in patients with celiac disease. A total of 68 children with confirmed celiac disease were enrolled for this study. Five-gram urine D-xylose test and D-xylose H2BT were performed simultaneously according to standard methods. Institute ethical clearance and informed consent was taken before starting this study. Of 68 children, 41 were boys and 27 girls of age range 5-14 years; 5-g urine D-xylose test was abnormal in 50% of cases and 5-g D-xylose H2BT in 69.9% of cases. D-xylose H2BT was able to pick up 19.9% more cases of malabsorption in Indian children with celiac disease. This study indicates that performance of 5-g D-xylose H2BT is a better test than 5-g urinary D-xylose test in screening for intestinal malabsorption in patients with celiac disease.

Cases referred for tests of thyroid function disorders at a tertiary care teaching hospital of Bihar: some experience

In the absence of valid hospital protocol for clinical departments of M.G.M. Medical College and L.S.K.Hospital, Kishanganj, as many as, 76.78% of patients was referred to biochemistry laboratory, in which disease was not present. Of 196 diseased (23.22% of total), male and female was respectively 44 and 152. There was no significant sex difference in positivity among patients referred for investigation. Hypothyroid was major diagnosis, yet hyperthyroid was noticeable.

Imidacloprid in processed tea and tea liquor

Imidacloprid is a newly introduced broad-spectrum chloronicotinyl insecticide and will find its way in agricultural production, particularly in Asia. However, information on the fate of imidacloprid in crop plants is lacking. The degradation of imidacloprid in processed CTC tea and tea liquor was investigated in the present study in which imidacloprid was applied at recommended application rate (30.0 g a.i./ha) and twice the recommended application rate (60.0 g a.i./ha) for three consecutive seasons. Imidacloprid was rapidly dissipated in processed tea following first order reaction kinetics at all application rates and had half-lives of 0.91-1.16 d with the residue in tea liquor found to be below detectable limit on 3rd day samples. The study revealed that imidacloprid is safe for human consumption and will not pose any residual toxicity problem.

Study on oxidative stress in patients with abdominal trauma

Reactive oxygen species have been implicated in the etiology of multiple organ dyspepsia syndrome and infection's complications in patients with trauma. But the oxidative stress and antioxidants levels in abdominal trauma have not yet been studied. Therefore, this study was planned to measure lipid peroxidation for oxidative stress and reduced glutathione, catalase and superoxide dismutase (SOD) for antioxidant levels in plasma & heamolysate of 30 patients with abdominal trauma and 30 controls. From this study we can summarize that there was an increase in oxidative stress and decrease in antioxidant levels (causing oxidative stress) on day zero in patients with abdominal trauma. This oxidative stress on day zero was not related to the development of complications. There was no significant difference in oxidative stress between patients with solitary and multiple abdominal organ injury and also between patients with hollow viscus injury and solid organ injury on day zero. From this study, we conclude that in patients with abdominal trauma there was increase in oxidative stress and decrease in antioxidant levels on day zero.

Anti-idiotype-mediated epitope spreading and diminished phagocytosis by a human monoclonal antibody recognizing late-stage apoptotic cells

Apoptotic cells are considered an important auto-antigenic source in diseases such as systemic lupus erythematosus (SLE). A human monoclonal antibody demonstrating exquisite specificity towards late-stage apoptotic cells was generated from an SLE patient. Polyreactive recognition of ribonucleoproteins Ro52 and Ro60 was observed. The antibody significantly diminished the phagocytosis of apoptotic cells and a concomitant decrease in transforming growth factor-beta (TGF-beta) secretion was observed. Light and heavy chain sequencing revealed the antibody to be in essentially germline configuration. Elicited anti-idiotypic antibodies bound distinct self-antigens and showed augmented reactivity towards apoptotic cells as well. Thus, near-germline encoded antibodies recognizing antigens externalized during the process of apoptosis can mediate a variety of potentially pathogenic effects; decreases in the phagocytic uptake of dying cells would constitute a disease-perpetuating event and stimulation of the idiotypic network could lead to intermolecular epitope spreading, increasing the range of molecular targets..

Role of N-acetylcysteine in rifampicin-induced hepatic injury of young rats

AIM: To study the role of N-acetylcysteine (NAC) as a protective agent in rifampicin (RMP)-induced oxidative hepatic injury of young rats.

METHODS: Hepatic injury was produced by giving 50mg/kg body weight/day of RMP for 3 wk. A dose of NAC (100mg/kg body weight/day) was given in combination with RMP intraperitoneally. Analysis of lipid peroxidation, thiol levels, cytochrome P₄₅₀, superoxide dismutase (SOD), catalase, glutathione peroxidase, reductase and transferase were estimated in liver along with the body weight, liver weight and histological observations.

RESULTS: RMP exposure resulted in no change in body and liver weight while antioxidative enzymes were altered but the non protein thiol (GSH) status was well preserved. Cytochrome P₄₅₀ system and peroxidation of lipids were induced by RMP exposure. Partial protection was observed with NAC against RMP-induced changes in liver, which was evidenced from the prevention of increase in lipid peroxidation and the reduction in SOD and catalase enzyme levels.

CONCLUSION: NAC protects young rats against RMP-induced oxidative hepatic injury.

Garlic hepatotoxicity: safe dose of garlic

Information on the effect of garlic on the liver and optimal dose of garlic to avoid liver damage is not known. This study was planned to determine the safe dose of garlic. Male wistar rats (110-170g) were fed fresh garlic homogenate (FSH) orally in three different doses (1.0, 2.5 and 5.0 g/kg body weight/day) daily for 28 days. Liver histology, serum transaminases, bilirubin and alkaline phosphatase were estimated at 0, 14, 21 and 28 days in control and experimental animals. 1.0, 2.5 and 5.0 g/kg body weight/day of garlic showed significant (P<0.001) deterioration in liver function tests (LFT's) after 21, 14 and 7 days respectively. A 1.0 g/kg body weight/day dose of garlic was associated with marked histological damage in liver after 21 days. Therefore, three lower doses of garlic (0.1, 0.25 and 0.5 g/kg body weight/day) were given orally to another group of similar rats to determine the safe dose of garlic. LFT's were serially measured and animals were sacrificed on the 29th day of experiment. All three lower doses showed significant deterioration in the LFT's values of animals after 28 days of feeding the freshly prepared garlic homogenate. Both doses of garlic i.e. 0.1 and 0.25 g/kg body weight/day were associated with normal histology of liver, but 0.5 g/kg body weight/day dose of garlic showed morphological changes in the liver of one animal. Therefore, the present study suggests that garlic with high dose has the potential ability to induce liver damage and low doses (0.1 or 0.25 g / kg body weight/day) are safe doses of garlic.

Effect of pencycuron on microbial parameters of waterlogged soil

A laboratory study was conducted to monitor the effect of pencycuron [1-(4-chlorobenzyl)-1-cyclopentyl-3-phenylurea] on microbial parameters of alluvial (AL) soil (Typic udifluvent) and coastal saline (CS) soil (Typic endoaquept) under waterlogged condition. Pencycuron at field rate (FR), 2FR and 10FR affected the microbial biomass C (MBC), soil ergosterol content and fluorescein diacetate hydrolyzing activity (FDHA) differentially. The DCM amendment did not seem to have any counteractive effect on the toxicity of pencycuron on the microbial variables. The change in microbial metabolic quotient (qCO2) and microbial respiration quotient (QR), indicated pencycuron induced disturbance at 10FR. Present study revealed that the metabolically activated microbial population was more suppressed compared to the dormant population.

Butachlor degradation in tropical soils: effect of application rate, biotic-abiotic interactions and soil conditions

The degradative characteristics of butachlor (N-Butoxymethyl-2-chloro-2',6'-diethyla- cetanilide) were studied under controlled laboratory conditions in clay loam alluvial (AL) soil (Typic udifluvent) and coastal saline (CS) soil (Typic endoaquept) from rice cultivated fields. The application rates included field rate (FR), 2-times FR (2FR) and 10-times FR (10FR). The incubation study was carried out at 30 degrees C with and without decomposed cow manure (DCM) at 60% of maximum water holding capacity (WHC) and waterlogged soil condition. The half-life values depended on the soil types and initial concentrations of butachlor. Butachlor degraded faster in AL soil and in soil amended with DCM under waterlogged condition. Microbial degradation is the major avenue of butachlor degradation from soils.

An integrated microfluidic device for influenza and other genetic analyses

An integrated microfluidic device capable of performing a variety of genetic assays has been developed as a step towards building systems for widespread dissemination. The device integrates fluidic and thermal components such as heaters, temperature sensors, and addressable valves to control two nanoliter reactors in series followed by an electrophoretic separation. This combination of components is suitable for a variety of genetic analyses. As an example, we have successfully identified sequence-specific hemagglutinin A subtype for the A/LA/1/87 strain of influenza virus. The device uses a compact design and mass production technologies, making it an attractive platform for a variety of widely disseminated applications.

Study of KAP of the private medical practitioners about national disease control programmes

This study was carried out among the Private Allopathic Medical Practitioners (PMPs) at Khardah Municipal area (West Bengal) to find out their perception & practice about management protocol of diseases like acute respiratory infections and diarrhoel diseases in children, malaria and tuberculosis. Data was collected by interviewing the PMPs with pre-designed open-ended questionnaire. It was supplemented by analysing sample prescriptions of the same diseases. The study revealed that PMPs knowledge and practice were not at par with national guidelines. The need for periodic sensitization of PMPs regarding national disease control programme was emphasized.

Pencycuron application to soils: degradation and effect on microbiological parameters

Clay loam soil from agricultural fields of alluvial (AL) soil (typic udifluvent) and coastal saline (CS) soil (typic endoaquept) were investigated for the degradation and effect of pencycuron application at field rate (FR), 2-times FR (2FR) and 10-times FR (10FR) with and without decomposed cow manure (DCM) on soil microbial variables under laboratory conditions. Pencycuron degraded faster in CS soil and in soil amended with DCM. Pencycuron spiking at FR and 2FR resulted in a short-lived (in case of 10FR slightly longer) and transitory toxic effect on soil microbial biomass-C (MBC), ergosterol content and fluorescein diacetate hydrolyzing activity (FDHA). Amendment of DCM did not seem to have any counteractive effect of the toxicity of pencycuron on the microbial variables. The ecophysiological status of the soil microbial communities as expressed by microbial metabolic quotient (qCO2) and microbial respiration quotient (Q(R)) changed, but for a short period, indicating pencycuron induced disturbance. The duration of this disturbance was slightly longer at 10FR. Pencycuron was more toxic to the metabolically activated soil microbial populations, specifically the fungi. It is concluded that side effects of pencycuron at 10FR on the microbial variables studied were only short-lived and probably of little ecological significance.

Dissipation of pencycuron in rice plant

Pencycuron is a non-systemic protective fungicide for controlling sheath blight of rice. However, information on the fate of pencycuron in rice plant is lacking. The degradation of pencycuron in waterlogged tropic rice field was investigated. Pencycuron was applied at recommended field dose (187.5 g a.i./ha) and double recommended dose to cropped plots for three consecutive years. Pencycuron was rapidly degraded in rice plant at all doses of pencycuron application with first order half-lives of 1.57 approximately 2.77 d. The study revealed that pencycuron is safe from the human and environmental contamination point of view.

Use of microsatellite marker loss of heterozygosity in accurate diagnosis of pancreaticobiliary malignancy from brush cytology samples

BACKGROUND

Brush cytology of biliary strictures to diagnose pancreaticobiliary malignancy suffers from poor sensitivity.

AIM

To improve the diagnostic yield of pancreaticobiliary brush cytology through analysis of tumour suppressor gene linked microsatellite marker loss of heterozygosity (LOH) and k-ras codon 12 mutation detection.

METHODS

Twenty six patients with biliary strictures underwent endoscopic retrograde cholangiography with brush cytology. A panel of 12 polymorphic microsatellite markers linked to six tumour suppressor genes was developed. Genomic DNA from cell clusters acquired from brush cytology specimens and microdissected surgical malignant and normal tissue underwent polymerase chain amplification reaction (PCR). PCR products were compared for LOH and k-ras codon 12 mutations.

RESULTS

Seventeen patients were confirmed to have pancreaticobiliary adenocarcinoma. Nine patients had benign strictures (eight proven surgically, one by follow up). Cytomorphological interpretation was positive for malignancy (n = 8), indeterminate (n = 10), and negative for malignancy (n = 8). Selected malignant appearing cytological cell clusters and microdissected histological samples from cancer showed abundant LOH characteristic of malignancy while brushings from nine cases without cancer carried no LOH (p<0.001). LOH and k-ras mutations profile of the cytological specimens was almost always concordant with the tissue samples. Presence of k-ras mutation predicted malignancy of pancreatic origin (p<0.001).

CONCLUSION

LOH and k-ras codon 12 mutation analysis of PCR amplified DNA from biliary brush cytology discriminates reactive from malignant cells, with 100% sensitivity, specificity, and accuracy. Minor variations in LOH in brushings and in different sites within the same tumour likely reflect intratumoral mutational heterogeneity during clonal expansion of pre- and neoplastic lineages.

Effect of arsenic contamination on microbial biomass and its activities in arsenic contaminated soils of Gangetic West Bengal, India

A study was conducted to see the effect of arsenic contamination on soil quality indicators, viz., microbial biomass, soil respiration, fluorescein diacetate and dehydrogenase (DHG) activity in arsenic contaminated soils of West Bengal. All the parameters were significantly and negatively correlated with all the form of arsenic (bioavailable and total) but the microbial metabolic quotient was significantly and positively correlated with all forms of arsenic, indicating arsenic induced stress to the soil microbial community. This may be due to part of the microbial biomass, which is located in the inner parts of the micro-aggregates of soil, which is affected by arsenic accumulates present in soil particles. Linear regression analysis revealed that the bioavailable arsenic exerted greater inhibitory effect on the soil microbial population than the total arsenic content of soils. Water-soluble arsenic showed more inhibitory effect than NaHCO(3) extractable form, in their association with biological properties of the contaminated soils. Water-soluble form of arsenic was much more toxic than insoluble forms. This signified that with increase in bioavailability, the arsenic exerted more inhibitory effect on these parameters. It is thus suggested that the microbial biomass, fluorescein diacetate and dehydrogenase activity alone and expressed on a soil organic matter basis along with the soil respiration parameters can be helpful in assessing the effects of arsenic on the size and activity of microbial biomass in soils.