Cumulative Noise Exposure and Perceived Effects: A Comparative Study Among Different Occupational Groups in Kolkata

Background

Adverse short-term and long-term health effects following a high level of noise have been established. The current study aims to find the relationship of these effects with an environment-specific level of noise exposure.

Materials and Methods

A comparative cross-sectional study was conducted among 50 auto-rickshaw drivers and 51 age-matched service-sector employees. The peak average noise exposure in decibels (dB) was measured. The duration of exposure and response regarding perceptions following noise exposure was assessed through a pre-designed pre-tested semi-structured questionnaire.

Results

The mean age of the participants was 42.24 (±13.72) years. Among the auto-rickshaw drivers, 82% perceived stress, 64% had hearing difficulty, and 74% complained of lack of sleep following exposure to a high level of noise. However, the perceptions were comparable among the comparison group and the differences were not statistically significant. The mean average peak level of noise exposure among drivers and their comparison group was 91.64 (±7.37) dB and 91.98 (± 8.06) dB, respectively, but were not different statistically. Around 52.94% of the service-sector respondents and 48% of the drivers were exposed to the lower cumulative noise levels. Those having a higher level of cumulative noise exposure, had a higher odds of feeling irritated (Odds ratio [OR]: 2.182, 95% confidence interval [CI]: 0.845-5.636), feeling stressed (OR: 5.805, 95% CI: 1.552-21.708), having palpitation (OR: 3.694, 95% CI: 1.264-10.793), and lack of sleep (OR: 3.020, 95% CI: 1.006-9.066).

Conclusion

Stress and lack of sleep were the most important perceived effects of noise exposure. The exposures to the higher cumulative noise level in specified groups were more important in relation to quantifying perceived symptoms than the average peak noise level.

How Covid-19 Affected the Work Prospects and Healthcare-Seeking of Women Domestic Workers in Kolkata City, India? A Longitudinal Study

BACKGROUND

Self-negligence, societal neglect, and lack of access to adequate health care make domestic workers vulnerable to ill-health. COVID-19 has adversely affected the work prospects of people across social classes and their health care-seeking opportunities as well. We studied the impact of COVID-19 pandemic on work prospects and health care-seeking behavior of a vulnerable section of the society - the women domestic workers.

METHODS

A longitudinal analysis on 292 randomly selected women domestic workers residing in slums of "Kalikapur" locality of Kolkata city, West Bengal (India). Data were collected using a predesigned and pretested schedule twice: in early-2020 (before severe impact of COVID-19) and mid-2020 (during the pandemic ravaging India). Paired t-test and McNemar's test were used to check for significant changes.

RESULT

Of all the participants, 57.2% lost jobs partially while 2.7% were completely jobless in mid-2020; the average daily work-hour decreased by 25.7%. Their average monthly pay significantly reduced (P < 0.05); mean family income in mid-2020 was lesser as well, compared to earlier (P < 0.05). Compared to early-2020, 15.8% more participants were sole bread-winners for their families during COVID-19. Number of participants visiting health practitioners significantly reduced (P < 0.05) in mid-2020. Rise in over-the-counter medicine use (P < 0.05) and increased tendency to ignore symptoms (P < 0.05) during COVID-19 was noted.

CONCLUSION

The COVID-19 pandemic has affected work prospects and health care-seeking behavior of women domestic workers negatively. Most of them faced wage reduction, many becoming sole-earners for their families. This necessitates continued formulation and implementation of strategies ensuring social benefits including healthcare. Awareness about affordable healthcare and ill-effects of bad practices like self-medication should also be built.

Antiangiogenic activity of zinc and zinc-sorafenib combination using the chick chorioallantoic membrane assay: A descriptive study

Aim

Zinc, a trace element, is known for downregulating several proangiogenic growth factors and cytokines. However, its antiangiogenic activity is not adequately studied. The present study was aimed to evaluate the possible antiangiogenic activity of zinc via the chick chorioallantoic membrane (CAM) assay. Furthermore, the antiangiogenic activity of the combination therapy of zinc with various doses of sorafenib, a tyrosine kinase inhibitor, was evaluated.

Materials and Methods

A pilot study was initially conducted so as to select suitable doses of zinc and sorafenib. The antiangiogenic activity after combining zinc 2.5 μg/embryo with sorafenib 1 and 2 μg/embryo was also evaluated. The antiangiogenic activity was quantified in terms of total length of blood vessels, number of junctions, number of branching points, and mean length of the blood vessels.

Results

Zinc 2.5 μg/embryo showed significant (P < 0.05) antiangiogenic activity, as compared to the control group. However, its effect was not comparable to that of sorafenib 2 μg/embryo. The combination of zinc 2.5 μg/embryo with sorafenib 2 μg/embryo did not show an additive/synergistic effect. The combination of zinc 2.5 μg/embryo with sorafenib 1 μg/embryo produced an antiangiogenic activity which was comparable (P > 0.05) to that of sorafenib 2 μg/embryo.

Conclusion

Zinc caused significant antiangiogenic activity in the CAM assay. The lack of addition/synergism in the zinc-sorafenib combination could have been due to the variability in the dose/ratio selection. Addition of zinc to sorafenib therapy could improve treatment tolerability, reduce cost of therapy, and reduce the emergence of drug resistance. Future mechanistic studies could identify the exact pharmacodynamics of zinc as an angiogenesis inhibitor.

Discovery of two novel laccase-like multicopper oxidases from Pleurotus citrinopileatus and their application in phenolic oligomer synthesis

BACKGROUND

Laccases and laccase-like multicopper oxidases (LMCOs) oxidize a vast array of phenolic compounds and amines, releasing water as a byproduct. Their low substrate specificity is responsible for their tremendous biotechnological interest, since they have been used for numerous applications. However, the laccases characterized so far correspond to only a small fraction of the laccase genes identified in fungal genomes. Therefore, the knowledge regarding the biochemistry and physiological role of minor laccase-like isoforms is still limited.

RESULTS

In the present work, we describe the isolation, purification and characterization of two novel LMCOs, PcLac1 and PcLac2, from Pleurotus citrinopileatus. Both LMCOs were purified with ion-exchange chromatographic methods. PcLac2 was found to oxidize a broader substrate range than PcLac1, but both LMCOs showed similar formal potentials, lower than those reported previously for laccases from white-rot fungi. Proteomic analysis of both proteins revealed their similarity with other well-characterized laccases from Pleurotus strains. Both LMCOs were applied to the oxidation of ferulic and sinapic acid, yielding oligomers with possible antioxidant activity.

CONCLUSIONS

Overall, the findings of the present work can offer new insights regarding the biochemistry and variability of low-redox potential laccases of fungal origin. Low-redox potential biocatalysts could offer higher substrate selectivity than their high-redox counterparts, and thus, they could be of applied value in the field of biocatalysis.

Attenuation of oxidative stress and neurotoxicity involved in the antidepressant-like effect of the MK-801(dizocilpine) in Bacillus Calmette-Guerin-induced depression in mice

Background The emerging line of research suggests that neuro-inflammation and oxidative stress are linked to the development of depression-like behavior. The tryptophan metabolizing enzyme, indolamine 2,3-dioxygenase (IDO), serves as an important interface between chronic inflammation and depression. IDO is induced by pro-inflammatory cytokines and diverts tryptophan towards the kynurenine pathway, decreasing serotonin synthesis. Further, the metabolites of kynurenine pathway increase brain oxidative stress and also cause N-methyl-D-aspartate (NMDA) receptor-mediated exitotoxicity. The resulting oxidative damage and dysfunction in glutamatergic neurotransmission alters the network connectivity of the brain, which may be the further mechanism for emergence of depression-like symptoms. Methods A depression-like illness was induced in mice by injecting Bacillus Calmette-Guerin (BCG) suspended in isotonic saline at a dose of 107 CFU I.P. The mice were then divided into different groups and were administered MK-801 or normal saline for the next 21 days, after which a battery of behavior and biochemical tests were conducted to assess them. Results The BCG group had significantly reduced sucrose preference index and an increase in immobility time in forced swim test (FST) and Tail Suspension Test (TST) as compared to the saline group. There was also a significant increase in the brain MDA levels and a decline in the brain GSH levels. The hippocampal tissue from the BCG group had significantly more comet cells than the saline group. The NMDA receptor antagonist, MK-801, was able to reverse the BCG-induced depression-like behaviour. MK-801 also showed significant decrease in brain oxidative stress but failed to show significant protection against BCG-induced neurotoxicity observed in comet assay. Conclusions The NMDA receptor antagonist, MK-801, mitigated BCG-induced, depressive-like behavior in mice by improving the sucrose preference and decreasing the duration of immobility time in TST and FST. The overall improvement in depression-like behavior was accompanied by a reduction in brain oxidative stress and comet cells, thus suggesting the antioxidant and neuroprotective action of MK-801.

Comparison of fluoxetine and 1-methyl-L-tryptophan in treatment of depression-like illness in Bacillus Calmette-Guerin-induced inflammatory model of depression in mice

BACKGROUND

The inflammatory response system has been implicated in the pathophysiology of major depression. The pro-inflammatory cytokines like interferon-γ induce the enzyme indoleamine-2,3-dioxygenase (IDO) of the kynurenine pathway of tryptophan metabolism. The induction of IDO reduces the availability of tryptophan for serotonin synthesis. Furthermore, the metabolites of kynurenine pathway have neurotoxic property, which along with decreased serotonin may account for depression-like illness.

METHODS

The aim of this study was to compare the effects of treatment with fluoxetine and 1-methyl-L-tryptophan (1-MT) on Bacillus Calmette-Guerin (BCG)-induced inflammatory model of depression in mice. Behavioral tests included locomotor activity, forced swim test (FST) and tail suspension test (TST). Oxidative stress was assessed by examining the levels of thiobarbituric acid reactive species (TBARS) and non-protein thiols (NP-SH) in homogenized whole brain samples. Comet assays were performed to assess neurotoxicity.

RESULTS

The results of this study demonstrate that BCG treatment resulted in an increase in duration of immobility in FST and TST as compared to the saline group. Further, it produced a significant increase in the brain TBARS levels and decrease in the brain NP-SH levels. The hippocampal tissue from BCG group had significantly more comet cells than the saline group. 1-MT and fluoxetine were able to reverse the BCG-induced depression-like behavior and the derangement in oxidative stress parameters. Fluoxetine and 1-MT also reversed the BCG-induced neurotoxicity in such mice.

CONCLUSIONS

1-Methyl-L-tryptophan exhibits antidepressant-like effect comparable to that of fluoxetine in treating BCG-induced depression-like behavior in mice.

Pharmacological characterization of the first in class clinical candidate PF-05190457: a selective ghrelin receptor competitive antagonist with inverse agonism that increases vagal afferent firing and glucose-dependent insulin secretion ex vivo

BACKGROUND AND PURPOSE

Ghrelin increases growth hormone secretion, gastric acid secretion, gastric motility and hunger but decreases glucose-dependent insulin secretion and insulin sensitivity in humans. Antagonizing the ghrelin receptor has potential as a therapeutic approach in the treatment of obesity and type 2 diabetes. Therefore, the aim was to pharmacologically characterize the novel small-molecule antagonist PF-05190457 and assess translational pharmacology ex vivo.

EXPERIMENTAL APPROACH

Radioligand binding in filter and scintillation proximity assay formats were used to evaluate affinity, and europium-labelled GTP to assess functional activity. Rat vagal afferent firing and calcium imaging in dispersed islets were used as native tissues underlying food intake and insulin secretion respectively.

KEY RESULTS

PF-05190457 was a potent and selective inverse agonist on constitutively active ghrelin receptors and acted as a competitive antagonist of ghrelin action, with a human Kd of 3 nM requiring 4 h to achieve equilibrium. Potency of PF-05190457 was similar across different species. PF-05190457 increased intracellular calcium within dispersed islets and increased vagal afferent firing in a concentration-dependent manner with similar potency but was threefold less potent as compared with the in vitro Ki in recombinant overexpressing cells. The effect of PF-05190457 on rodent islets was comparable with glibenclamide, but glucose-dependent and additive with the insulin secretagogue glucagon-like peptide-1.

CONCLUSIONS AND IMPLICATIONS

Together, these data provide the pharmacological in vitro and ex vivo characterization of the first ghrelin receptor inverse agonist, which has advanced into clinical trials to evaluate the therapeutic potential of blocking ghrelin receptors in obesity and type 2 diabetes.

Isotopic disequilibrium in Globigerina bulloides and carbon isotope response to productivity increase in Southern Ocean

Oxygen and carbon isotope ratios in planktonic foraminifera Globigerina bulloides collected from tow samples along a transect from the equatorial Indian ocean to the Southern Ocean (45°E and 80°E and 10°N to 53°S) were analysed and compared with the equilibrium δ¹⁸O and δ¹³C values of calcite calculated using the temperature and isotopic composition of the water column. The results agree within ~0.25‰ for the region between 10°N and 40°S and 75–200 m water depth which is considered to be the habitat of Globigerina bulloides. Further south (from 40°S to 55°S), however, the measured δ¹⁸O and δ¹³C values are higher than the expected values by ~2‰ and ~1‰ respectively. These enrichments can be attributed to either a ‘vital effect’ or a higher calcification rate. An interesting pattern of increase in the δ¹³C(DIC) value of the surface water with latitude is observed between 35°S and~ 60°S, with a peak at~ 42°S. This can be caused by increased organic matter production and associated removal. A simple model accounting for the increase in the δ¹³C(DIC) values is proposed which fits well with the observed chlorophyll abundance as a function of latitude.

An improved method of high-precision determination of Δ(17)O of CO2 by catalyzed exchange with O2 using hot platinum

RATIONALE

CO2 and O2 can exchange their oxygen isotopes rapidly in the presence of hot (~670 °C) platinum and this has led to a method for determining the δ(17)O value of a CO2 sample. We have improved the method to achieve a precision of 0.008 ‰ (1-σ standard deviation) in the determination of δ(17)O values. Such high precision is essential to identify the stratospheric component in tropospheric CO2 and use it for global carbon flux studies. The crucial issue in the accurate determination of the δ(17)O value is estimation of a correction factor, which depends on the amount ratio CO2/O2. An attempt was also made to investigate the mechanism of exchange with their controlling parameters.

METHODS

The oxygen isotopes of a CO2 sample gas are exchanged with those of an appropriate amount of tank O2 in the presence of hot platinum. The pre-exchange CO2 and O2 gas samples as well as the post-exchange O2 sample are analyzed by isotope ratio mass spectrometry. A mixing model was developed involving the δ(18)O value of the CO2 and δ(17)O and δ(18)O values of pre- and post-exchange O2 to obtain the δ(17)O value of the CO2 sample. A correction to the measured value was determined to obtain the actual value with high accuracy and precision.

RESULTS

To obtain a precision better than 0.01 ‰ requires the amount ratio CO2/O2 to be controlled to better than ~15 %. We also find that the oxygen isotopes are nearly homogeneously distributed between the O2 and the CO2 molecules. In addition, determination of the (16) O(13)C(18)O/(16)O(12)C(16)O isotopologue ratio in the CO2 shows that the abundance of (16)O(13)C(18)O is close to that expected for random partitioning of the isotopes among the CO2 isotopologues.

CONCLUSIONS

The isotopic scrambling between O2 and CO2 that occurs on hot platinum allows one to accurately determine the δ(17)O values of CO2 through isotopic analysis of O2.

Effectiveness of an Educational Feedback Intervention on Drug Prescribing in Dental Practice

Background Irrational use of drugs as well as inappropriate and over drug prescribing leads to unnecessary expenditures and emergence of resistant bacterial strains. Feedback intervention on drug prescribing habits and face to face educational intervention of prescription audit would be effective in rationalizing prescribing practices. Objective To measure the impact of educational feedback intervention on the prescribing behavior of dental surgeons. Methods Prospective audit of twelve hundred outpatients prescriptions in dental OPD at BPKIHS of those dental surgeon who attended the educational intervention session was collected randomly by trained persons on customized data collection sheet before and after educational intervention. Results A total 1200 prescription were collected, 300 before and 300 after intervention period at the internal of one month, three months and six months. Majority of the prescriptions (39.33%) contained four drugs but after intervention, prescriptions contained mostly one drug, 73% in first month, 78.67% in third month and 65.34% in six month. Mean number of drugs per prescription after intervention were decreased. There was increased number of generic names of drugs after intervention. Amoxicillin, Metronidazole, Chlorhexidine, Povidone iodine gargle, Nimesulide, Ibuprofen, Ibuprofen + paracetamol, and Paracetamol were most commonly prescribed by dental prescribers before and after intervention. Selection of antimicrobial was done on empirical basis which was correct because Amoxicillin concentration reaches effectively in gingival crevicular fluid and Metronidazole covered effectively against anaerobic bacteria were found in orodental infection. The uses of topical anti-infective preparation as irrigants of choice that can kill majority of micro-organisms found is root canal and dental tubules and minimize systemic use of antimicrobials. Nimesulide prescribing needs to be rationalized. Conclusion Feedback educational intervention of prescription audit is effective to improve their prescribing behaviors and rationalize drug utilization pattern for the benefit of the patients. DOI: http://dx.doi.org/10.3126/kumj.v10i4.10991 Kathmandu Univ Med J 2012;10(4):30-35

Prostaglandin E1-induced Catalepsy in the Rat: Role of Putative Neutrotransmitters

Prostaglandin E1 (PGE1) produced dose-related catalepsy in rats when administered intracerebroventricularly. PGE1 induced catalepsy was significantly inhibited after pretreatment with pharmacological agents known to attenuate central serotonergic and cholinergic activity. It was also inhibited by PGF2α and naloxone. On the contrary, treatments enhancing central dopaminergic activity also reduced the cataleptic effect of PGE1. The results suggest that PGE1 induces catalepsy in rats by modulating activity of central neurotransmitters.

Prostaglandin d2 induced potentiation of the anticonvulsant actions of phenobarbitone and phenytoin in rats. Role of serotonin

Prostaglandin D2 (PGD2) produced a dose-related potentiation of the anticonvulsant actions of sub-effective doses of phenobarbitone and phenytoin against maximal electroshock-induced seizures in rats. PDG2-induced potentiation of phenobarbitone and phenytoin was significantly attenuated following pretreatment with centrally administered 5,6-dihydroxytryptamine, a selective neurotoxin for serotonergic neurones, p-chlorophenylalanine, a specific inhibitor of serotonin biosynthesis, and methysergide, a serotonin receptor antagonist, indicating that the potentiation was serotonin-mediated.

Prostaglandins and central serotonergic activity in the rat

Pharmacological and biochemical studies indicate that prostaglandins (PGs) exert a modulatory influence on rat brain serotonergic activity. With several experimental approaches, it has been shown that PGEs and PGD2 facilitate central serotonergic activity in rats. On the contrary, PGF2α not only inhibits rat brain serotonergic activity but also antagonizes the facilitatory effect of the other PGs. The studies support the proposed neuromodulatory role for PGs in central synaptic transmission.

Naloxone blocks the beneficial effects of aqueous extract of Murraya koenigii (L.) Spreng leaves in models of pain

AIM

This study investigated the antinociceptive effects of aqueous extract of Murraya koenigii (AEMK) leaves (200, 400 and 800 mg/kg, orally) on animal models of acute and persistent pain and its modulation by naloxone.

MATERIALS AND METHODS

Antinociceptive effects were assessed using tail-flick, hot plate and formalin tests in mice. To differentiate between central and peripheral antinociceptive effect of AEMK, naloxone (2 mg/kg) was administered along with the 800 mg/kg dose of extract. Morphine was used as a standard drug.

RESULTS

AEMK and morphine significantly increased the tail-flick latency (tfl) and paw licking/jumping latency in tail-flick and hot plate tests, respectively, in comparison to control. Also, in both the tests AEMK and morphine significantly increased the AUC0-120 min. In formalin test, AEMK (400 mg/kg and 800 mg/kg) and morphine significantly reduced licking time in both early and late phases in comparison to control.

CONCLUSIONS

Thus, in all three pain models AEMK showed antinociceptive effect, which was blocked by naloxone suggesting the involvement of opioidergic central mechanism.

Tobacco and alcohol: the relation to pulmonary tuberculosis in household contacts

Tuberculosis is transmitted commonly by droplet nuclei and facilitated by weak immune system. Lowered immunity may be associated with cigarette smoking, tobacco chewing and alcohol consumption. The co-relationship between these all factors to TB should be explored. This study aims to detect the hidden household contacts (HC) cases early and to examine the relative contribution of tobacco and alcohol use to the risk of TB. Across-sectional study was in Dharan among HCs. From June 2009 to May 2010, 184 index cases with sputum smear positive for AFB and their 802 HCs were included. Three sputum specimens were collected from each HCs and examined microscopically for AFB detection. AFB were detected in sputum of 13 (1.6%) HCs. The association between habits (alcohol user and smoking) and TB was found except with chewing tobacco user (P > 0.05). The risk of contact TB was 4 and 8 times greater in smoker (OR = 3.94 95% CI = 1.26-12.26, P < 0.05) and alcoholic (OR = 8.23 95% CI = 2.71-24.98, P < 0.05) HCs respectively. This study has revealed smoking and alcohols as the risk factors for tuberculosis. Effective campaign to discourage use of alcohol and tobacco, and awareness programme about the mode of transmission of TB are needed in community.

Prevalence of tuberculosis in household contacts of sputum smears positive cases and associated demographic risk factors

Pulmonary tuberculosis (PTB) is transmitted by aerosolized droplets nuclei. Home is the vulnerable place for transmission of this disease to its contacts. Risk factors associated with this contact transmission may differ according to locality. This study aims to determine the prevalence of household contact (HC) PTB and examine the risk factors contributing to it. A cross-sectional study was conducted to determine the prevalence of HC TB among HCs aged > 5 years in Dharan. During the study period (June 2009 - May 2010), 184 index cases with sputum smear positive for AFB and their 802 HCs were included. Three sputum specimens were collected from each HCs and examined microscopically for AFB detection. The prevalence of HC TB was found to be 1.6%. The result was statistically associated (P < 0.05) with illiterate HCs (OR= 5.77, 95%CI =1.52-21.81), close proximity with ICs (OR=3.07, 95%CI = 1.02-9.25), primary relatives to ICs (OR= 4.85, 95%CI = 1.07-22.05) and slum dweller (OR = 4.56, 95%CI = 1.25-16.71). Similarly, AFB positivity was associated (P<0.05) with household crowding (OR = 7.46, 95%CI = 2.36-23.49), room size < or = 10 x 10 feet (OR=4.05, 95%CI = 1.23-13.25), firewood user while cooking (OR = 5.96, 95%CI = 1.92-18.45). The prevalence of HCs tuberculosis is found to be 1.6%. Poverty, illiteracy, overcrowding, close proximity, close relation with ICs, firewood while cooking, slum dweller, are major factors highlighted by this study as risk factors of contact TB. Our results recommend a much better contact tracing and treatment program.

Etiological agents of corneal ulcer: five years prospective study in eastern Nepal

To identify the most common isolates from the corneal ulcers with antimicrobial pattern of bacterial isolates. All patients with suspected corneal ulceration presenting to BP Koirala Institute of Health Sciences from Jan 2004 - Dec 2008 were evaluated. Corneal scraping was performed and processed for direct microscopy, bacteriological and fungal culture. Bacterial isolates were subjected to antimicrobial susceptibility testing. Of 351 specimens examined, growth of etiological agents were obtained in 278 (79.20%). Of these, 113 (40.65%) had pure fungal growth, 108 (38.85%) had pure bacterial growth and 57 (20.50%) had mixed fungal and bacterial infection. The commonest fungal pathogen was Aspergillus spp 50 (33.33%) followed by Fusarium spp 19 (12.66%). Staphylococcal aureus 57 (44.53%) was isolated as commonest bacterial agent. Coagulase Negative Staphylococci 20 (15.6%) was second in the list. Pseudomonas spp 12 (9.40%) was the most common gram negative bacilli isolated. Most of the bacterial isolates were sensitive to commonly used antibiotics. Corneal Ulcer is a common problem in eastern Nepal. Knowledge of both fungal and bacterial agents associated with this condition is of value for the prevention and management of corneal ulcers and their complications.

Measurement of the 17O-excess (Δ17O) of tropospheric ozone using a nitrite-coated filter

RATIONALE

The (17)O-excess (Δ(17)O) of tropospheric ozone (O(3)) serves as a useful marker in studies of atmospheric oxidation pathways; however, due to the complexity and expense of currently available analytical techniques, no systematic sampling campaign has yet been undertaken and natural variations in Δ(17)O(O(3)) are therefore not well constrained.

METHODS

The nitrite-coated filter method is a new technique for O(3) isotope analysis that employs the aqueous phase NO(2)(-) + O(3) → NO(3)(-) + O(2) reaction to obtain quantitative information on O(3) via the oxygen atom transfer to nitrate (NO(3)(-)). The triple-oxygen isotope analysis of the NO(3)(-) produced during this reaction, achieved in this study using the bacterial denitrifier method followed by isotope-ratio mass spectrometry (IRMS), directly yields the Δ(17)O value transferred from O(3). This isotope transfer process was investigated in a series of vacuum-line experiments, which were conducted by exposing coated filters to O(3) of various known Δ(17)O values and then determining the isotopic composition of the NO(3)(-) produced on the filter.

RESULTS

The isotope transfer experiments revealed a strong linear correlation between the Δ(17)O of the O(3) produced and that of the oxygen atom transferred to NO(3)(-), with a slope of 1.55 for samples with bulk Δ(17)O(O(3)) values in the atmospheric range (20-40‰). This finding is in agreement with theoretical postulates that place the (17) O-excess on only the terminal oxygen atoms of ozone. Ambient measurements yield average Δ(17)O(O(3))(bulk) values in agreement with previous studies (22.9 ± 1.9‰).

CONCLUSIONS

The nitrite-coated filter technique is a sufficiently robust, field-deployable method for the determination of the triple-oxygen isotopic composition of tropospheric O(3). Further ambient measurements will undoubtedly lead to an improved quantitative view of natural Δ(17)O(O(3)) variation and transfer in the atmosphere.

Tuberculin reactivity in bacille calmette-guerin vaccinated individuals with sputum positive pulmonary tuberculosis

The study was carried out to assess the value of tuberculin skin test for the diagnosis of Tuberculosis (TB) in BCG vaccinated individuals and to find out the sensitivity rate of tuberculin skin test (TST) in comparison to acid fast bacilli positive pulmonary TB. Similar population with high BCG vaccination coverage having both pulmonary TB patients (n=150) and apparently healthy individuals (n=150) in eastern Nepal were enrolled in this comparative study. Sputum from all the subjects was subjected to Z-N microscopy. TST was performed on these subjects by standard Mantoux method. Among the patients (mean age 36.18±14.15 yrs) and controls (mean age 35.61±13.44 yrs), 55.33 % and 47.33 % respectively have been found to be positive PPD reactors (>10mm) which is statistically not significant (P>0.05). About 23% of the patients & 27% of controls failed to react (anergic) to 5 TU PPD. PPD reactivity rate was high in the patients whose sputum smears were graded as 1+ in Z-N microscopy. The sensitivity of TST was highest for the induration of >5mm (77.3%). Specificity increased with increasing size of induration and was highest (73.3%) with induration of >15 mm. Tuberculin skin test is an all or none phenomenon. In Nepal, tuberculin test has a limited value in the diagnosis of pulmonary TB as both the apparently healthy individuals and patients with sputum smear positive pulmonary TB who had been immunized with BCG, showed almost similar rate of tuberculin reactivity. DOI: http://dx.doi.org/10.3126/jcmsn.v7i1.5970 JCMSN 2011; 7(1): 28-35

In vitro activity of cefoperazone-sulbactam combination against gram negative bacilli

Cefoperazone is a â-lactam antimicrobial and Sulbactam is an irreversible â-lactamase inhibitor. The objective of this study was to know the susceptibility pattern of gram negative bacilli (GNB) towards cefoperazone-sulbactum. All GNB isolated from different clinical samples during the period of May, 2010 to Aug, 2010 were tested for susceptibility to cefoperazone-sulbactum, meropenem, ceftazidime, cefotaxime, ceftriaxone, chloromphenicol, cotrimoxazole, ampicillin, amikacin, nalidixic acid, ciprofloxacin, carbenicillin and piperacillin using standard Kirby-Bauer disc diffusion antimicrobial susceptibility testing method. The susceptibilities were recorded according to CLSI guidelines. A total of 406 GNB were isolated (urine: 66.7%, pus: 19.2%, and blood: 7.9%). Escherichia coli (54.4%) was most frequently isolated organisms followed by Acinetobacter species (17.7%), Klebsiella pneumoniae (9.1%) and Pseudomonas species (6.1%). Overall, 11.8% of isolates showed resistance to cefoperazone-sulbactam. Frequencies of isolates showing resistance to meropenem and amikacin were 14.7% and 26.25% respectively. Only 3.9% of Escherichia coli isolates showed resistance to cefoperazone-sulbactam. For other organisms, their lowest frequency ranging from 0-20%, exhibited resistance to meropenem. In Pseudomonas spp, in-vitro activity of amikacin was also better as only 11.1% isolates showed resistance to it. This study demonstrated the in-vitro synergistic effect of cefoperazonerazone-sulbactam and meropenem having good activity against GNB compared to the activity of other commonly tested antimicrobials. Cefoperazone-sulbactam can be recommended for the clinical practice against GNB exhibiting resistant to other antimicrobials as it is cheaper alternative to meropenem. Our results also focused on the continuous surveillance of the trends and features of resistance of common antimicrobials.

Signet ring cell carcinoma of the gallbladder: a case report

Carcinoma of the gall bladder is the most common biliary tract tumor with higher incidence in females and increasing age. The risk is significantly higher in cholelithiasis. Signet ring cell carcinoma is a rare form of mucinous adenocarcinoma and has a worse prognosis. Early diagnosis is rare. We report a case of signet ring cell carcinoma of the gall bladder in a 70 years old female patient. The gross finding was yellowish white mass measuring 4 x 3.5 cm on cut surface of the gall bladder along with thickened wall. Histopathological examination of the specimen shows the sheets of signet ring cells with lateral spread through the lamina propria and large amount of extracellular mucin. There was metastasis in the retroperitoneum and mesenteric lymph node. The tumor was stage IV (according to TNM staging). Patient died 20th post operative day. Since very few cases have been reported, information regarding the behavior and prognosis of gall bladder carcinoma is limited. However it has been seen that stage III and IV carcinoma usually have worse prognosis.

Study of patients with painless inguinal hernia in the quality of life

Inguinal hernias are one of the commonest surgical problems in our set up. It is a protrusion of abdominal cavity contents through the inguinal canal. This is a retrospective study done in the Department of Surgery, Nepal Medical College Teaching Hospital (NMCTH) from January 2009 to December 2010. During this period, 120 patients with painless hernia were enrolled in the study. The age range was from 30 years to 76 years with mean age of presentation at 53 years. Out of 120 patients who underwent mesh repair only 74 patients (61.7%) had visible hernia on standing and 46 patients (38.3%) had palpable impulse on cough. 90 patients (75%) were males and indirect hernia (53.3%) was more common than direct hernia. Out of 120 cases, 30 cases underwent inguinal neurectomy which on follow up had no pain at all. In other 90 cases, neurectomy was not confirmed from the operative note. In these 90 cases, 12 patients had mild pain and 10 patients had moderate to severe pain on 6 months follow up. To conclude, surgical repair is recommended for painless inguinal hernia as most of the patients develop symptoms over time and to avoid undue complications.

Effect of Ocimum sanctum, ascorbic acid, and verapamil on macrophage function and oxidative stress in mice exposed to cocaine

OBJECTIVE

To investigate the effect of Ocimum sanctum, ascorbic acid, and verapamil on macrophage function and oxidative stress in experimental animals exposed to cocaine.

MATERIALS AND METHODS

Mice were used in this study and were divided randomly into different groups of six animals each. They were either treated with intraperitoneal injection of saline or cocaine hydrochloride or an oral feeding of oil of Ocimum sanctum, ascorbic acid or verapamil, or both (ascorbic acid and verapamil), and were evaluated for a respiratory burst of macrophages, superoxide and nitric oxide (NO) production, estimation of TNF-alpha in the serum and supernatant of cultured macrophages, estimation of lipid peroxidation (malondialdehyde- MDA) in the serum, and superoxide dismutase activity in the erythrocytes.

RESULTS

Unstimulated respiratory burst as well as superoxide production was enhanced on treatment with cocaine and all the three drugs were found to attenuate this enhancement. The bactericidal capacity of macrophages decreased significantly on chronic cocaine exposure, as it was associated with decreased respiratory burst and superoxide production. There was a significant decrease in NO production by macrophages on chronic cocaine exposure and all the test drugs were found to restore nitrite formation to a normal level. There was an increase in the malonylodialdehyde (MDA) level and decrease in the superoxide dismutase level on chronic cocaine exposure, and all the three drugs effectively decreased the MDA level and increased superoxide dismutase level. There was an increase in serum TNF-alpha on chronic cocaine exposure, which was decreased significantly by ascorbic acid and verapamil.

CONCLUSION

O. sanctum, ascorbic acid, and verapamil were equally effective in improving the macrophage function and reducing oxidative stress. These findings suggested that O. sanctum, ascorbic acid, and verapamil attenuated acute and chronic cocaine-mediated effects.

Antimicrobial Resistant Streptococcus pneumoniae

Introduction: Pneumococcal infections are important cause of morbidity and mortality. Knowledge of antimicrobial susceptibility patterns plays important role in the selection of appropriate therapy.  Present study was undertaken to analyze the susceptibility patterns of pneumococcal isolates against  commonly used antimicrobials with special reference to determination of minimum inhibitory  concentration (MIC) of penicillin in a tertiary care hospital in eastern Nepal. Methods: Twenty-six strains of S. pneumoniae isolated from various clinical specimens submitted to microbiology laboratory were evaluated. All isolates were tested for antimicrobial susceptibility by  disk diffusion method. MIC of penicillin was tested by broth dilution method. Results: Of the total isolates 19 (73%) were from invasive infections. Seven isolates were resistant to cotrimoxazole. No resistance to penicillin was seen in disk diffusion testing. Less susceptibility to penicillin (MIC 0.1-1.0 mg/L) was observed in five (17%) isolates. High level resistance to penicillin was not detected. One isolate was multidrug resistant. Conclusions: S. pneumoniaeisolates with intermediate resistance to penicillin prevail in Tertiary Care Hospital in eastern Nepal, causing invasive and noninvasive infections. As intermediate resistance is not detected in routine susceptibility testing, determination of MIC is important. It helps not only in the effective management of life threatening infections but is also essential in continuous monitoring and early detection of resistance. In addition, further study on pneumococcal infections, its antimicrobial resistance profile and correlation with clinical and epidemiological features including serotypes and group prevalence is recommended in future. Keywords: antimicrobial susceptibility pattern, penicillin, Streptococcus pneumoniae.

Elimination of neglected tropical diseases in the South-East Asia Region of the World Health Organization

The neglected tropical diseases (NTDs), which affect the very poor, pose a major public health problem in the South-East Asia Region of the World Health Organization (WHO). Although more than a dozen NTDs affect the region, over the past five years four of them in particular - leprosy, lymphatic filariasis, visceral leishmaniasis (kala-azar) and yaws - have been targeted for elimination. These four were selected for a number of reasons. First, they affect the WHO South-East Asia Region disproportionately. For example, every year around 67% of all new leprosy cases and 60% of all new cases of visceral leishmaniasis worldwide occur in countries of the region, where as many as 850 million inhabitants are at risk of contracting lymphatic filariasis. In addition, several epidemiological, technological and historical factors that are unique to the region make each of these four diseases amenable to elimination. Safe and effective tools and interventions to achieve these targets are available and concerted efforts to scale them up, singly or in an integrated manner, are likely to lead to success. The World Health Assembly and the WHO Regional Committee, through a series of resolutions, have already expressed regional and global commitments for the elimination of these diseases as public health problems. Such action is expected to have a quick and dramatic impact on poverty reduction and to contribute to the achievement of the Millennium Development Goals. This paper reviews the policy rationale for disease control in the WHO South-East Asia Region, the progress made so far, the lessons learnt along the way, and the remaining challenges and opportunities.

Antimicrobial resistant Streptococcus pneumoniae

INTRODUCTION

Pneumococcal infections are important cause of morbidity and mortality. Knowledge of antimicrobial susceptibility patterns plays important role in the selection of appropriate therapy. Present study was undertaken to analyze the susceptibility patterns of pneumococcal isolates against commonly used antimicrobials with special reference to determination of minimum inhibitory concentration (MIC) of penicillin in a tertiary care hospital in eastern Nepal.

METHODS

Twenty-six strains of S. pneumoniae isolated from various clinical specimens submitted to microbiology laboratory were evaluated. All isolates were tested for antimicrobial susceptibility by disk diffusion method. MIC of penicillin was tested by broth dilution method.

RESULTS

Of the total isolates 19 (73%) were from invasive infections. Seven isolates were resistant to cotrimoxazole. No resistance to penicillin was seen in disk diffusion testing. Less susceptibility to penicillin (MIC 0.1-1.0 mg/L) was observed in five (17%) isolates. High level resistance to penicillin was not detected. One isolate was multidrug resistant.

CONCLUSIONS

S. pneumoniae isolates with intermediate resistance to penicillin prevail in Tertiary Care Hospital in eastern Nepal, causing invasive and noninvasive infections. As intermediate resistance is not detected in routine susceptibility testing, determination of MIC is important. It helps not only in the effective management of life threatening infections but is also essential in continuous monitoring and early detection of resistance. In addition, further study on pneumococcal infections, its antimicrobial resistance profile and correlation with clinical and epidemiological features including serotypes and group prevalence is recommended in future.

Ayurvedic processed seeds of nux-vomica: neuropharmacological and chemical evaluation

The effect of detoxification on Strychnos nux-vomica seeds by traditional processing with aloe and ginger juices (B), by frying in cow ghee (C), and by boiling in cow milk (D) was investigated. The ethanolic extracts of these samples were subjected to spontaneous motor activity (SMA), pentobarbitone-induced hypnosis, PTZ induced convulsions, diazepam-assisted protection, and morphine-induced catalepsy. All samples reduced SMA and inhibited catalepsy. The seeds processed in milk (D) showed the lowest strychnine content in the cotyledons, exhibited marked inhibition of PTZ induced convulsions and maximal potentiation of hypnosis, and were the safest (LD(50)).

Phenotypic characterisation and drug sensitivity testing of mycobacteria isolated from extra-pulmonary tuberculosis

BACKGROUND

Tuberculosis (TB) is a major cause of morbidity and mortality globally, with most cases occurring in developing countries. The importance of extra pulmonary tuberculosis (EPTB) among all forms of tuberculosis has not yet been ascertained in developing countries.

OBJECTIVE

To identify and perform phenotypic characterization of clinically important mycobacterium isolates from extra-pulmonary sites along with drug susceptibility testing.

MATERIALS AND METHODS

A total of 513 specimens from patients of (EPTB) with varied presentation were studied. Speciation and characterization of isolates were done on the basis of growth and biochemical characteristics. Drug susceptibility testing for mycobacterium isolates was done by proportion method.

RESULTS

Fifty four patients clinically suspected to have extra-pulmonary tuberculosis were culture positive for mycobacteria. On characterization 48 of the 54 isolates were identified as M. tuberculosis, 4 as M. bovis and 2 were M. avium/intracelulare. Drug susceptibility testing was done for the both M. tuberculosis as well as M. bovis. In single drug resistance, Streptomycin was highest followed by Isoniazid, Ethambutol and Refampicin. Multi drug resistance (MDR) was found in 6 isolates and it was observed only in group I cases.

CONCLUSION

EPTB accounts for 10-15 percent of all cases of tuberculosis. Mycobacterium was present in 10.5 percent samples. 48 isolates out of 54 samples were found to be M. tuberculosis. The maximum numbers of M. tuberculosis were isolated from lymph node aspiration.

Vaccine desirability during an effectiveness trial of the typhoid fever polysaccharide Vi vaccine in Kolkata India

BACKGROUND

High rates of typhoid fever and the emergence of multi-drug resistant strains create a need for prevention efforts including vaccines. Socio-behavioral research can provide important data for participation in future trials and public health vaccination campaigns.

DESIGN

A 3b phase clinical trial in Kolkata India including pre- and post-vaccination socio-behavioral surveys.

RESULTS

47.9% of respondents were male. Ward 29 respondents included 32.4% Hindu and Ward 30 respondents were 99.0% Hindu. Lower rates of participation were found among Muslim respondents and those with post high school education. Lack of information and negative information affected participation. Joint decision-making within households increased participation rates.

METHODS

seven hundred households were randomly selected 503 respondents (71.85%) completed both the pre- and post-closed-ended surveys. Data analysis included descriptive statistics, Pearson's chi-square tests, independent t-tests, and stepwise logistic regression analysis. Four open-ended questions were included in the survey. These qualitative data were coded and reviewed for common themes and patterns.

CONCLUSIONS

Individuals' decisions to participate or not participate in a vaccine trial entail a balance between individual beliefs, household dynamics and socio-political influences. Efforts prior to vaccination trials need to develop strategies which address potential underlying mediators for belief systems as well as structural factors which may reinforce individuals' beliefs and perceptions about vaccination trials.

Anomalous enrichment of 17O and 13C in photodissociation products of CO2: possible role of nuclear spin

Oxygen and carbon isotope fractionation associated with products (CO and O(2)) of gas phase photodissociation of CO(2) have been studied using photons from Hg lamp (184.9 nm) and Kr lamp (123.6 and 116.5 nm). In dissociation by Hg lamp photons both CO and O(2) are enriched in (17)O by about 81 per thousand compared to the estimate based on a kinetic model. Additionally, CO is enriched in (13)C by about 37 per thousand relative to the model composition. In contrast, in dissociation by higher energy Kr lamp photons no such anomaly was found in O(2). The observed isotopic enrichments in case of Hg lamp dissociation are proposed to be due to a hyperfine interaction between nuclear spin and electron spins or orbital motion causing enhanced dissociation of isotopologues of CO(2) containing (17)O and (13)C. The (17)O enrichment is higher than that of (13)C by a factor of 2.2+/-0.2 which can be explained by the known magnetic moment ratio of (17)O and (13)C due to differing nuclear spins and g-factors. These results have potential implications in studies of the planetary atmospheres.

Epidemiological and bacteriological profile of burn patients at Nepal Medical College Teaching Hospital

This study was conducted to know the epidemiological and bacteriological profile of burn patients at Nepal Medical College Teaching Hospital. The charts of 50 burn patients admitted in department of surgery were reviewed retrospectively. All the epidemiological characteristics, mode of injury, time taken to reach hospital and involved body surface areas were noted. The charts were also reviewed for bacterial isolates from burn wounds and its sensitivity pattern for various antibiotics. Data was analyzed using the statistical package for social sciences (SPSS) for Windows. The mean age of patients was 31.8 years with male:female ratio of 1.3:1. Half of the patients were from Kathmandu. Fifty two percent of patients directly came to our hospital while rests were referred from other hospitals. The average time taken to reach hospital was 11.3 hours. Those patients who were referred from outside the valley took longer time (p = 0.002). Flame burn was the leading cause for injury (66.0%) followed by scald burn (16.0%), electric burn (14.0%) and acid burn (4.0%). Staphylococcus aureus (28.0%) was the commonest organism isolated from wound swab culture. Others were Klebsiella (16.0%), Pseudomonas (13.0%), Proteus (13.0%) and E.coli (13.0%). No growth was noted in 17.0% of patients. During the treatment, 14.0% of patients died and 4.0% left against medical advice. Remaining patients were discharged after complete recovery. Body surface area involvement was found to be a significant predictor of mortality (p < 0.001) and the length of hospital stay was significantly low for them (p = 0.05).

Prescription Writing Skills of Pre-Clinical Medical and Dental Undergraduate Students

Objective of this prospective study was to assess the acquisition of prescribing skill of preclinicalmedical and dental undergraduate students. Prescription writing skills of 258 students of both firstand second year of MBBS and BDS students were analyzed through an objective structured practicalexamination. MBBS student of second year scored 85.01% and 92.82% respectively in physician anddrug related component whereas first year MBBS students scored 89.9% and 83.4%. BDS studentof first year scored 91.96% and 86.33% in physician and drug related components which is betterthan second year that scored 83.33% and 77.94% respectively. This study revealed that the studentsof both courses acquire prescribing skills to a limited extent during preclinical phase. Prescribingerrors were found both in physician and drug related components. To minimize the different form ofprescribing errors vigorous training in the internship period will help to minimize prescribing errorsand improve rational prescribing too.Key words: dental, examination, medical, objective, prescription, student

Prescription writing skills of pre-clinical medical and dental undergraduate students

Objective of this prospective study was to assess the acquisition of prescribing skill of preclinical medical and dental undergraduate students. Prescription writing skills of 258 students of both first and second year of MBBS and BDS students were analyzed through an objective structured practical examination. MBBS student of second year scored 85.01% and 92.82% respectively in physician and drug related component whereas first year MBBS students scored 89.9% and 83.4%. BDS student of first year scored 91.96% and 86.33% in physician and drug related components which is better than second year that scored 83.33% and 77.94% respectively. This study revealed that the students of both courses acquire prescribing skills to a limited extent during preclinical phase. Prescribing errors were found both in physician and drug related components. To minimize the different form of prescribing errors vigorous training in the internship period will help to minimize prescribing errors and improve rational prescribing too.

A community-based, comparative evaluation of direct agglutination and rK39 strip tests in the early detection of subclinical Leishmania donovani infection

In the Indian state of Bihar, the sensitivities and specificities of direct agglutination tests (DAT) and rK39 test strips for the detection of Leishmania donovani infection in humans were explored and found to be generally good (92%-100%). When 172 asymptomatic individuals [16 'case-contacts' who lived in the same households as past or current, confirmed cases of visceral leishmaniasis (VL) and 156 other subjects from neighbouring households] were tested, the same 36 (21%) individuals, including all 16 'case-contacts', were found seropositive using each type of test. When followed-up after 3 months, 18 of the individuals who had been found seropositive in the baseline survey remained seropositive, and eight (44%) of these had developed symptomatic VL, with amastigotes in their splenic aspirates. Seven (44%) of the 16 'case-contacts' but only one (5%) of the other 20 subjects found seropositive at baseline went on to develop VL within 3 months. Although the strip test appeared slightly better than DAT for predicting the development of VL in the 172 subjects, either type of test may be very useful for the early detection of asymptomatic L. donovani infection and thus the identification of those at relatively high risk of developing VL.

Impact of amphotericin-B in the treatment of kala-azar on the incidence of PKDL in Bihar, India

BACKGROUND & OBJECTIVE

Of the two reservoirs of infection of kala-azar i.e., patients of kala-azar and post kala-azar dermal leishmaniasis (PKDL), PKDL provides easy access for the sandfly to pick up the parasites. In the last epidemic of 1977 in India, the importance of PKDL as a potential cause of increase in number of kala-azar cases was ignored. During recent years, we found an increase in the cases of kalaazar whereas cases of PKDL were decreasing in Bihar. We undertook this study to find out reasons for this phenomenon.

METHODS

These three different settings were selected to study the trends of the disease. (i) Cases of PKDL registered in the Dermatology Department of Patna Medical College Hospital (PMCH), one of the largest and oldest teaching hospital in Bihar, between 1970 and 2005; (ii) Rajendra Memorial Research Institute of Medical Sciences, Patna (RMRIMS), a research institute exclusively devoted to kala-azar (2000 and 2005); and (iii) interviews with two leading dermatologists of Patna selected by lottery on the incidence of PKDL and possible causes of its decrease, if any. The number of cases of kala-azar (visceral leishmaniasis, VL) from Bihar was studied from Malaria Departments of the Government of Bihar and Government of India, the two nodal departments dealing with the kala-azar.

RESULTS

Analysis of data from Dermatology Department of PMCH showed increase in number of cases of PKDL from two in 1970 to 12 in 1976, a year before the first epidemic of kala-azar in 1977 with 100,000 cases. Kala-azar cases decreased to 11,120 in 1982 due to control measures taken between 1977- 1979 but cases of PKDL reached 28 and kept on increasing. During 1950 to 1977, low dose and short duration regimen of sodium antimony gluconate (SAG) was mainly used in the treatment of kala-azar. Between 1977-1991 increasing incidence of unresponsiveness to SAG, led to the usage of longer duration and higher dose regimen of SAG, more use of amphotericin B (AMB) for SAG resistant cases and also as a first line drug for kala-azar and PKDL. The number of kala-azar cases started decreasing after control measures taken during 1992-1994 but cases of PKDL continued decreasing. The effect of control measures on the incidence of kala-azar was visible upto 2002, but decrease in number of PKDL cases continued. In 2005 the number of PKDL cases was 14 but number of kala-azar cases reached 21,177 in Bihar. In the interview, the two dermatologists also opined that PKDL was decreasing due to increased use of amphotericin B in the treatment of kala-azar. Trend analysis done on the data of PMCH and RMRIMS showed that PKDL will decrease in coming years and kala-azar will increase.

INTERPRETATION & CONCLUSION

Incidence of PKDL decreased in PMCH and RMRIMS and also suggested by two dermatologists that extensive use of amphotericin B in the treatment of kala-azar might be responsible for decrease in number of cases of PKDL.

Dual culture method to determine the relationship of gut bacteria of sandfly (Phlebotomus argentipes) with promastigotes of Leishmania donovani

A simple dual culture agar plating technique has been developed and evaluated for its efficiency in determining the relationship of gut bacteria of sandfly with Leishmania donovani promastigotes. There are about twenty morphologically distinct bacterial colonies have been isolated from the gut homogenate of Phlebotomus argentipes. In dual culture method, each bacterial isolate was inoculated in one half of the plate and the promastigotes of Leishmania was inculcated in the other half by streaking. After incubation, the type of association was determined based on the presence or absence of promastigotes colonies. The reliability of this method was compared with broth dilution method in 96 well plate.

Lack of effect of SU1498, an inhibitor of vascular endothelial growth factor receptor-2, in a transgenic murine model of retinoblastoma

SU1498, a tyrosine kinase inhibitor of vascular endothelial growth factor receptor 2 (VEGFR-2), has activity against retinal neovascular diseases. To determine if this drug might have clinical utility against retinoblastoma, we evaluated the effects of SU1498, as well as the expression of VEGFR-2, in a transgenic animal model of retinoblastoma. Optical coherence tomography (OCT) was evaluated as a technology to measure retinal tumors in vivo, in response to treatment. Immunofluorescence analysis was performed to evaluate the distribution and expression of VEGFR-2 in enucleated eyes from LHβTag transgenic mice and controls at 4, 8, 12, and 16 weeks of age. VEGFR-2 and phosphorylated (p)VEGFR-2 levels were quantitated by Western blot. OCT was used to pair 10-week-old animals based on tumor volume (n=10), and these animals were treated with 6 periocular injections of SU1498 (50mg/kg, given twice weekly) or vehicle for 3 weeks. Tumor burden was determined by histology and in vivo imaging by OCT. VEGFR-2 and pVEGFR-2 expression levels were upregulated during tumorigenesis. However, SU1498 did not significantly reduce tumor burden compared to vehicle (p=0.29). OCT imaging of one matched pair demonstrated equivalent, linear tumor growth despite treatment with SU1498. Retinal tumors can be followed non-invasively and quantitatively measured with OCT. VEGFR-2 is strongly upregulated during tumorigenesis in transgenic retinoblastoma; however, SU1498 does not decrease tumor volume in transgenic murine RB at the studied dose and route of administration.

Recent advancement in drug delivery system

Ease of drug administration, safety, affordability and efficacy are the major concerns in pharmacotherapy leading to exploration of better drug delivery systems. Liposomes are lyotropic liquid crystals composed mainly of amphiphilic bilayers and these are more frequently used as drug carriers. Liposomes help reduce the toxicity and deliver the drug to the target tissue. So far, liposomes have been the most intensively studied lipid-based delivery system. In liposomes, a hydrophilic drug can be trapped in aqueous interior or channels between successive phospholipids bilayers whereas a hydrophobic drug can reside with the bilayer itself. The non-toxic and nonimmunogenic bilayers dissipate allowing the diffusion of the drug into the tissues. Attachment of polyethyl glycol to the surface of liposome (known as stealth liposome) aids in the better targeting of the drug to the tissues. Pegylated proteins and polymers of lactic and glycolic acids have been well studied as drug carriers and found to be resistant to phagocytosis and complement activation. Newer DNA based strategies including DNA vaccination and antisense oligonucleotides and immunomodulation show good results for new therapeutic systems. Though the DNA based therapeutic systems have high selectivity and specificity with few adverse effects, these systems are so far restricted to animal models and clinical trials.

Relationship between plasma leptin and plasma insulin levels in type-2 diabetic patients before and after treatment with glibenclamide and glimepiride

Type 2 diabetes affects 100 million people throughout the world. Among the various factors implicated in the causation of this disease, the role of leptin, an obesity gene product, is increasingly being investigated. This especially assumes importance in the light of knowledge that obesity confers a minimum of 3-10 fold higher risk of diabetes. This study was planned to investigate the relationship between leptin and insulin levels in type 2 diabetic patients before and after treatment with glibenclamide or glimepiride. 60 type 2 diabetic patients were recruited for the study and were divided into 2 groups-one receiving glimepiride and the other group receiving glibenclamide for duration of 10 weeks. This study demonstrated a highly positive correlation of plasma leptin levels with BMI, plasma insulin and insulin resistance. No gender specific differences were observed in leptin concentrations. The study, however, failed to demonstrate any possible relationship between glycemic control as assessed by blood sugars/ glycosylated hemoglobin (HbAlc) and plasma leptin. The administration of glibenclamide or glimepiride significantly lowered blood glucose levels coupled with a decrease in (HbAlc). Both the drugs increased insulin concentrations. Glibenclamide increased leptin levels but they remained unaltered with glimepiride. Glibenclamide and glimepiride were found to be equally effective in their glucose lowering action. However, the patients receiving glibenclamide experienced higher episode of hypoglycaemic spells than those receiving glimepiride.

Polyarthritis associated with testicular tumour

Rarely rheumatological features may dominate and is the cause of missed or delayed diagnosis of a malignant lesion. A case is presented wherein the patient with embryonal type of testicular tumour masqueraded with symmetrical polyarthritis with small joint involvement. p53 antigen was detected in testicular tissue. Such an example is indeed unreported in literature to the best of our knowledge.

Adults' perceived prevalence of enteric fever predicts laboratory-validated incidence of typhoid fever in children

This study was undertaken to develop a model to predict the incidence of typhoid in children based on adults' perception of prevalence of enteric fever in the wider community. Typhoid cases among children, aged 5-15 years, from epidemic regions in five Asian countries were confirmed with a positive Salmonella Typhi culture of the blood sample. Estimates of the prevalence of enteric fever were obtained from random samples of adults in the same study sites. Regression models were used for establishing the prediction equation. The percentages of enteric fever reported by adults and cases of typhoid incidence per 100,000, detected through blood culture were 4.7 and 24.18 for Viet Nam, 3.8 and 29.20 for China, 26.3 and 180.33 for Indonesia, 66.0 and 454.15 for India, and 52.7 and 407.18 for Pakistan respectively. An established prediction equation was: incidence of typhoid (1/100,000= -2.6946 + 7.2296 x reported prevalence of enteric fever (%) (F=31.7, p<0.01; R2=0.992). Using adults' perception of prevalence of disease as the basis for estimating its incidence in children provides a cost-effective behavioural epidemiologic method to facilitate prevention and control of the disease.

Wilson disease with visceral leishmaniasis: an extremely uncommon presentation

Visceral leishmaniasis (VL), which is caused by the protozoa Leishmania donovani and transmitted by the bite of the female sand fly Phlebotomus argentipes, is common in Bihar, India. Wilson disease is an autosomal recessive disorder of copper metabolism in which copper is deposited in the brain and liver. We report a case of an extremely uncommon combination of these diseases in a patient. Treatment options for such a combination of diseases are limited and difficult.

Use of rK39 for diagnosis of post kala-azar dermal leishmaniasis in Nepal

A recently developed nitrocellulose-based dipstick test, rK39, has been widely used for the diagnosis of kala-azar. In this study, we evaluated its use for the diagnosis of post kala-azar dermal leishmaniasis (PKDL). We also investigated the time taken by patients to develop PKDL after apparent cure of kala-azar (visceral leishmaniasis, VL) and the time taken by patients to come to the hospital after the appearance of symptoms of PKDL. A majority of patients developed the disease within three years after the apparent cure of kala-azar (KA). A majority of patients sought treatment within five years after the onset of PKDL. The amastigotes of Leishmania donovani bodies (LDBs) were demonstrated in 70, 20, and 20% of slit-skin smears (SSS) prepared, respectively, from nodular, papular, and macular forms. The presence of highest density (6+) LDBs in the SSS of 20% of nodular PKDL patients indicated that they may have acted as reservoir in the community. Other reservoirs are not known in Nepal. Only 8% cases were detected by aldehyde test. Although this test is obsolete it is still used in rural parts of Nepal. The dipstick (rK39) was 96% sensitive and 100% specific to diagnose PKDL. Its positive predictive value, negative predictive value, and diagnostic efficacy were 100, 91, and 97% respectively. Due to the advantage of cost compared with the direct agglutination test (DAT), and being easy to use and store in field conditions, rK39 is a good tool to diagnose PKDL in rural situations. All the PKDL patients were cured of the disease after treatment by SAG.

Intestinal parasitism and Vibrio cholerae infection among diarrhoeal patients in Kolkata, India

In this study, we have analysed the epidemiological significance of the concurrent infections caused by Vibrio cholerae and intestinal parasites among different age groups of hospitalized diarrhoeal patients in Kolkata. A total of 3556 stool samples collected during 1996-2004 were screened for vibrios and parasites. The seasonality of V. cholerae and parasitic infections were studied in detail. The detection rates for Ascaris lumbricoides and Giardia lamblia infection were more than for the hookworm, Trichuris trichiura and Entamoeba histolytica. V. cholerae O1 was identified as the predominant serogroup among diarrhoeal patients. The highest rates for V. cholerae infection were in the 2-5 years age group and combined infection of V. cholerae and parasites was recorded among children aged between 2 and 10 years.

Occurrence, significance & molecular epidemiology of cholera outbreaks in West Bengal

BACKGROUND & OBJECTIVE

Diarrhoeal disease outbreaks are causes of major public health emergencies in India. We carried out investigation of two cholera outbreaks, for identification, antimicrobial susceptibility testing, phage typing and molecular characterization of isolated Vibrio cholerae O1, and to suggest prevention and control measures.

METHODS

A total of 22 rectal swabs and 20 stool samples were collected from the two outbreak sites. The V. cholerae isolates were serotyped and antimicrobial susceptibility determined. Pulsed- field gel electrophoresis (PFGE) was performed to identify the clonality of the V. cholerae strains which elucidated better understanding of the epidemiology of the cholera outbreaks.

RESULTS

Both the outbreaks were caused by V. cholerae O1 (one was caused by serotype Ogawa and the other by serotype Inaba). Clinically the cases presented with profuse watery diarrhoea and dehydration. All the tested V. cholerae isolates were sensitive to tetracycline, gentamycin and azithromycin but resistance for ampicillin, co-trimoxazole, nalidixic acid, and furazolidone. PFGE pattern of the isolates from the two outbreaks revealed that they were clonal in origin. Stoppage of the source of water contamination and chlorination of drinking water resulted in terminating the two outbreaks.

INTERPRETATION & CONCLUSION

The two diarrhoeal outbreaks were caused by V. cholerae O1 (Inaba/Ogawa). Such outbreaks are frequently seen in cholera endemic areas in many parts of the world. Vaccination is an attractive disease (cholera) prevention strategy although long-term measures like improvement of sanitation and personal hygiene, and provision of safe water supply are important, but require time and are expensive.