Viability kinetics, induction, resuscitation and quantitative real-time polymerase chain reaction analyses of viable but nonculturable Vibrio cholerae O1 in freshwater microcosm

AIM

To study the induction of a viable but nonculturable (VBNC) state in Vibrio cholerae O1 in freshwater, in response to cold temperatures (4°C) and starvation.

METHODS AND RESULTS

Vibrio cholerae O1 cells were inoculated in freshwater microcosm and incubated at 4°C. The cells became coccoid, rugose and subsequently nonculturable by day 16 on tryptic soy agar (TSA) and by day 23 on TSA-SP, while 87 and 65% of the cells retained their membrane integrity, respectively. Viable cells were observed until day 30 using direct fluorescent antibody-direct viable count method. In vitro resuscitation was demonstrated by temperature upshift. Utilizing 16S rRNA as an endogenous control, the DNA pol II (27·43-fold), fliG (12·44-fold), ABC transporter (27·11-fold), relA (60·76-fold) and flaC (15·29-fold) were significantly up-regulated in VBNC cells, while the expression of fadL-3 was comparable. The expression of DNA pol II, fliG, ABC transporter, relA and flaC was 3·3, 1·1, 5·9, 5·8 and 1·2-fold, respectively, for resuscitated cells. VBNC cells were found to be virulent, as ctxA and tcpA were expressed.

CONCLUSIONS

Vibrio cholerae undergoes both phenotypic alteration and genotypic modulation to protect itself from stress in freshwater.

SIGNIFICANCE AND IMPACT OF THE STUDY

Induction and resuscitation of the VBNC state in freshwater is important for an understanding of the epidemiology of cholera in the freshwater environment.

Distribution and ethnic variation of â-thalassemia mutations in Nepal

This is the first study characterizing spectrum of beta-thalassemia mutations in Nepalese population. Mutations were analyzed in 22 patients using 10 sets of allele-specific primers. Five of the mutations, namely F.S 41/42 (--TCTT), IVS1 nt5 (G-->C), IVS1 nt1 (G-->T), 619 bp deletion and F.S 8/9 (+G), were found to constitute 87.82% of total alleles studied. F.S 41/42 (--TCTT) was the commonest mutation. -88 (C-->T), Codon 16 (--C) and Codon 15 (G-->A), had a combined frequency of 12.18%. Distribution of mutations causing beta-thalassemia in different ethnic Nepalese groups was analyzed. The mutational profile in Nepal share several similarities with that from the two neighboring countries, India and China. Detection of more than one mutation in three cases of thalassemia trait raises the likelihood of existence of multiple mutations in cis in Nepalese thalassemic carriers. Such possibility has to be carefully considered while developing prenatal screening program for Nepalese population.

Environmental and epidemiological surveillance of Vibrio cholerae in a cholera-endemic region in India with freshwater environs

AIM

To conduct epidemiological and ecological surveillance of cholera in freshwater environments.

METHODS AND RESULTS

A freshwater region of India was surveyed between April 2007 and December 2008. Vibrio cholerae was isolated from 59·5% of water and plankton samples (n = 357) and 35·5% of stool samples (n = 290). Isolation from water was dependent on air (r = 0·44) and water temperatures (r = 0·49) (P < 0·01) but was independent of rainfall (r = 0·15), chlorophyll a (r = 0·18), salinity (r = 0·2) or pH (r = 0·2) (P > 0·05). Isolation from plankton was dependent on temperature of air (r = 0·45), water temperature (r = 0·44), chlorophyll a concentration (r = 0·42), pH (r = 0·23) and salinity (r = 0·39) (P < 0·01). Cholera cases correlated with rainfall (r = 0·82, P < 0·01) and chlorophyll a concentration (r = 0·42, P < 0·05), but not with air temperature (r = 0·3, P = 0·37). Vibrio cholerae O1 possessed ctxB, ctxA, rstR and tcpA (ElTor), toxR, toxT, rtxA, rtxC, mshA and hylA. Among non-O1-non-O139, the distribution of virulence-associated and regulatory protein genes was heterogeneous with - 0·7, 2·2, 94·77, 97·76, 99·25, 100 and 100% isolates being positive for tcpA, toxT, rtxA, rtxC, hylA, toxR and mshA, respectively. Two-thirds of non-O1-non-O139 isolates exhibited antibiotic resistance to various antibiotics that did not correlate with geographical site or time of origin for the isolates. RAPD and AFLP showed V. cholerae to be a diverse bacterium. AFLP demonstrated separate lineages for non-O1-non-O139 and O1 isolates.

CONCLUSION

Environmental parameters played a significant role in the emergence and spread of cholera and the abundance of V. cholerae. But based on virulence gene profiling and genetic fingerprinting, the possibility of origin of toxigenic isolates from nontoxigenic environmental isolates seems unlikely in freshwater environs of India.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study explains the ecology, epidemiology and seasonality of cholera in freshwater environs.

A naïve Gaussian Bayes classifier for detection of mental activity in gait signature

A probabilistic modelling is presented to detect mental activity from gait signature recorded from healthy subjects. The proposed scheme is based on principal component analysis with reduced feature dimension followed by a naïve Gaussian Bayes classifier. The leave-one-out cross-validation shows the detection accuracy of 94% with specificity and sensitivity of 96% and 98.3%, respectively. The research has a potential application in the prevention of elderly risk falls, lie detection and rehabilitation among Parkinson's patients.

RP - HPLC method for the estimation of Tamsulosin Hydrochloride in Tablet Dosage Form

A rapid and sensitive reverse phase RP-HPLC method is proposed for the estimation of tamsulosin hydrochloride in tablets. Tamsulosin hydrochloride was chromatographed on a reverse phase C18 column with a mobile phase consisting of acetonitrile and water in the ratio of 50:50 v/v. The mobile phase was pumped at a flow rate of 1.5 ml/min. The eluents were monitored at 214 nm. The retention time of the drug was 1.7 min. With this method, linearity was observed between area under curve and concentration of tamsulosin hydrochloride in the injected solution, in the range of 5 to 100 μg/ml. The method was found to be applicable for analysis of the drug in tablets. The results were validated statistically.

Condyloma acuminatum: atypical presentation during pregnancy

Genital warts (condylomata acuminata) are caused by human papillomavirus (HPV) and are usually transmitted sexually. We present an atypical case of a vaginal wart presenting as a single pedunculated mass protruding outside the vagina in a pregnant woman in labour. On examination of the vulva, a soft, pink papilliferous growth of 6 × 4 cm size was seen hanging outside the vaginal introitus. Speculum examination revealed that the growth was attached to the posterior and lateral vaginal wall near the fornix. Genital warts can proliferate during pregnancy due to altered immunity and increased blood supply, as seen in this case. Vaginal warts can also cause problems during delivery, since they prevent the vagina from stretching appropriately.

Preliminary investigation of foot pressure distribution variation in men and women adults while standing

BACKGROUND

Women and men are anatomically and physiologically different in a number of ways. They differ in both shape and size. These differences could potentially mean foot pressure distribution variation in men and women. The purpose of this study was to analyze standing foot pressure image to obtain the foot pressure distribution parameter - power ratio variation between men and women using image processing in frequency domain.

METHODS

We examined 28 healthy adult subjects (14 men and 14 women) aged between 20 and 45 years was recruited for our study. Foot pressure distribution patterns while standing are obtained by using a PedoPowerGraph plantar pressure measurement system for foot image formation, a digital camera for image capturing, a TV tuner PC-add on card, a WinDvr software for still capture and Matlab software with dedicated image processing algorithms have been developed. Various PedoPowerGraphic parameters such as percentage medial impulse (PMI), fore foot to hind foot pressure distribution ratio (F/H), big toe to fore foot pressure distribution ratio (B/F) and power ratio (PR) were evaluated.

RESULTS

In men, contact area was significantly larger in all regions of the foot compared with women. There were significant differences in plantar pressure distribution but there was no significant difference in F/H and B/F ratio. Mean PR value was significantly greater in men than women under the hind foot and fore foot. PMI value was greater in women than men. As compared to men, women have maximum PR variations in the mid foot. Hence there is significant difference at level p<0.05 in medial mid foot and mid foot PR of women as compared to men.

CONCLUSION

There was variation in plantar pressure distribution because the contact area of the men foot was larger than that of women foot. Hence knowledge of pressure distributions variation of both feet can provide suitable guidelines to biomedical engineers and doctor for designing orthotic devices for reliving the area of excessively high pressure.

Prevalence and associations of hepatitis C viremia in hemodialysis patients at a tertiary care hospital

Hepatitis C virus (HCV) infection in hemodialysis (HD) is a significant problem. We evaluated the prevalence and associations of HCV viremia in our HD patients. All patients undergoing maintenance HD at our center were tested for HCV RNA by PCR after written informed consent. Detailed history regarding age, sex, and duration of dialysis, frequency of dialysis, blood transfusions in one year, number of dialysis centers, dialyzer reuse/fresh use, and recent laboratory data was recorded. A total of 119 patients (77 males and 42 females) were tested for HCV RNA. Thirty three (27.7%) tested positive. Duration of dialysis was significantly longer in HCV RNA positive group (P = 0.001). 45.2% of patients with duration of dialysis more than 16 months were HCV RNA positive while only 7.4% of patients with dialysis duration ≤16 months were HCV RNA positive (P < 0.001). In univariate analysis, in HCV RNA group patients, ALT, AST, and GGTP were significantly elevated and albumin was significantly lower. 39% of patients who had dialysis at more than one center were HCV RNA positive as compared to 20% for patients undergoing dialysis at single center (P = 0.024). Binary logistic regression analysis showed albumin, duration of dialysis, and serum ALT to be significant variables. Sensitivity and specificity of anti-HCV ELISA was 72.7 and 97.7%, respectively. Prevalence of HCV RNA in the HD population is 27.7%. Duration of dialysis, getting dialysis at more than one center, elevated transaminase levels, and low serum albumin are important associations for HCV RNA positivity.

Antibacterial Activity of Ethanol Extract of Andrographis paniculata

In the present study the ethanol extract of the aerial part of Andrographis paniculata was prepared and evaluated for antimicrobial activity against eleven bacterial strains by determining minimum inhibitory concentration and zone of inhibition. Minimum inhibitory concentration values were compared with control and zone of inhibition values were compared with standard ciprofloxacin in concentration 100 and 200 μg/ml. The results revealed that, the ethanol extract is potent in inhibiting bacterial growth of both Gram-negative and Gram positive bacteria.

Effect of caffeine and taurine on simulated laparoscopy performed following sleep deprivation

Background

Sleep deprivation affects surgical performance and has the potential to endanger patient safety. Pharmacological stimulants may counter this consequence of long working hours. This study aimed to investigate whether commonly available stimulants can counter the effects of fatigue on technical and neurocognitive skill.

Methods

This was a single-blind crossover study of surgical novices trained to proficiency on the Minimally Invasive Surgical Trainer—Virtual Reality laparoscopic simulator. Participants were acutely sleep-deprived three times each, followed by administration of either placebo, 150 mg caffeine, or 150 mg caffeine combined with 2 g taurine before simulated laparoscopy. Outcome measures were: laparoscopic psychomotor skill, cognitive performance and the Stanford Sleepiness Scale (range 1–7). Rested baselines were gathered following completion of test sessions.

Results

Baseline performance was recorded for 18 participants in the rested state. Sleep-deprived participants receiving the placebo took longer (median 41 versus 35 s; P = 0·016), were less economical with movement (3·25 versus 2·95 m; P = 0·016) and made more errors (66 versus 59; P = 0·021) on the laparoscopic task compared with the rested state. Caffeine restored psychomotor skills to baseline for time taken (37 versus 35 s; P = 0·101), although the number of errors remained significantly greater than in the rested state (63 versus 59; P = 0·046). Sleep-deprived subjects receiving placebo had slower reaction times (377 versus 299 ms; P = 0·008) and a higher score on the Stanford Sleepiness Scale (6 versus 2 points; P = 0·001) than rested surgeons. Negative effects of sleep deprivation on reaction time were reversed when caffeine (307 ms versus 299 ms in rested state; P = 0·214) or caffeine plus taurine (326 versus 299 ms; P = 0·110) was administered. Subjective sleepiness was also improved, but not to baseline levels.

Conclusion

Sleep deprivation affects laparoscopic psychomotor skills, reaction time and subjective measures of sleepiness in novice surgical subjects. Caffeine and taurine restore simulated laparoscopic performance to rested levels, but do not reduce errors.

A randomized clinical trial to compare the efficacy of different doses of intravaginal misoprostol with intracervical dinoprostone for cervical ripening and labor induction

OBJECTIVES

To compare the efficacy of 25 vs. 50 microg of intravaginal misoprostol vs. intracervical dinoprostone for cervical ripening and labor induction.

MATERIALS AND METHODS

210 women with Bishop's score <6 were randomized into 3 groups of 70 each to receive 6 hourly doses of either 25 or 50 microg of intravaginal misoprostol or 0.5 mg intracervical dinoprostone to maximum of 3 doses and outcome parameters were compared.

RESULTS

Induction to vaginal delivery interval was significantly lower (p < 0.05) for 50 microg (13.8 +/- 6.62 hours) as compared to 25 microg misoprostol (16.4 +/- 7.34 hours) or dinoprostone group (16.3 +/- 7.49 hours). Maximum improvement (p < 0.05) in Bishop's score and minimum oxytocin requirement (p < 0.05) was seen with misoprostol 50 microg. No significant difference was observed for women delivering vaginally within 24 hours (93.8 vs. 89.7 vs. 85.4%), patients delivering after one dose (24.3 vs. 21.4 vs. 20%), cesarean deliveries, fetal outcome, complications like hyperstimulation and fetal heart abnormalities for the 50 vs. 25 microg misoprostol vs. dinoprostone group.

CONCLUSION

Intravaginal misoprostol 50 microg administered 6 hourly appears to be most effective as it has least induction to delivery time, has maximum improvement in Bishop's score, least oxytocin requirement without any increase in complication rate.

Intra-lesional steroid for the management of symptomatic Infantile Digital Fibromatosis

BACKGROUND

Infantile Digital Fibromatosis (IDF) is a benign, often asymptomatic nodular proliferation of fibrous tissue occurring almost exclusively on the extremities. Conventional treatment has included radical surgery but this is associated with a high level of recurrence. Whilst some authors suggest a strictly conservative approach, this is unacceptable when lesions become symptomatic from pain, contracture formation or functional deformity

METHODS

We present a retrospective analysis of 12 symptomatic lesions of which 7 were treated with a novel technique of intra-lesional steroid. From 2004-2009, a total of ten patients received treatment for symptomatic IDFs. Patients were followed-up for an average of 5 years 9 months (range 8-131 months).

RESULTS

Corticosteroid was well tolerated with no significant complications and was associated with lower morbidity that compared with surgery. There was no significance difference between rate of recurrence (1/7 vs. 5/10) for those treated with corticosteroid than compared to those patients who underwent surgery (p = 0.3) but the study is underpowered.

CONCLUSIONS

This is the first ever study to look at the role of intra-lesional steroid in the management of IDF. Whilst the majority of asymptomatic Infantile Digital Fibromatoses can be safely observed until natural resolution, intra-lesional corticosteroid is a safe and well-tolerated alternative to surgery for all symptomatic digital fibromatoses of infancy. We suggest it replaces surgery as first-line treatment but look forward to a large multicentre trial to allow comparison.

Demonstration of viable but nonculturable Vibrio cholerae O1 in fresh water environment of India using ciprofloxacin DFA-DVC method

AIM

To demonstrate the presence of culturable and nonculturable viable pathogenic Vibrio cholerae O1 in fresh water environments of a cholera-endemic region in India.

METHODS AND RESULTS

Conventional culture and ciprofloxacin DFA-DVC were utilized to investigate the existence of V. cholerae O1. We isolated pathogenic culturable V. cholerae O1 from water samples collected from cholera-affected areas. No culturable V. cholerae O1 was isolated from water and plankton samples from natural fresh water bodies. Ciprofloxacin was used for DFA-DVC as V. cholerae O1 are 100% resistant to nalidixic acid in our region. The viable but nonculturable O1 cells were demonstrated in 2.21 and 40.69% samples from natural water bodies and cholera-affected areas, respectively.

CONCLUSION

Vibrio cholerae O1 VBNC could be demonstrated using modified DFA-DVC technique. Ciprofloxacin is preferable to nalidixic acid for DVC in view of existing high-level resistance to nalidixic acid in cholera-endemic areas.

SIGNIFICANCE AND IMPACT OF THE STUDY

We endorse that for public health surveillance, cholera outbreak investigation and disease control water samples in addition to culture should be tested for V. cholerae using DFA-DVC.

Occurrence of Gnathostoma spinigerum in free range tigress

Postmortem examination of free-range tigress of Pench Tiger Reserve, MP, India, aged approx 15 years revealed nodule in the pyloric part of the stomach packed with worms and was identified as Gnathostoma spinigerum on the basis of morphology of male and female worms, including eggs.