Seasonal Transition in PM10 Exposure and Associated All-Cause Mortality Risks in India.

Lack of a consistent PM10 (particulate matter smaller than 10 µm) database at high spatial resolution hinders in assessing the environmental impact of PM10 in India. Here we propose an alternate approach to estimate the PM10 database. Aerosol extinction coefficients at the surface are calculated from midvisible aerosol optical depth from MERRA-2 reanalysis data using characteristics vertical profiles from CALIOP and then are converted to PM10 mass using aerosol property information and microphysical data. The retrieved PM10 are bias-corrected and evaluated ( R2 = 0.85) against coincident ground-based data maintained under the Central Pollution Control Board network. PM10 exposure exceeds Indian annual air quality standard in 72.3% districts. Transition in PM10 exposure from the monsoon (Jun-Sep) to postmonsoon season (Oct-Nov) translates to 1-2% higher all-cause mortality risk over the polluted Indo-Gangetic Basin (IGB). Mortality risk increases in the central to eastern IGB and central India and reduces in Delhi national capital region in the winter (Dec-Feb) relative to the postmonsoon season. Mortality risk decreases by 0.5-1.8% in most parts of India in the premonsoon season (Mar-May). Our results quantify the vulnerability in terms of seasonal transition in all-cause mortality risks due to PM10 exposure at district level for the first time in India.

Efficient gradient computation for dynamical models.

Data assimilation is a fundamental issue that arises across many scales in neuroscience - ranging from the study of single neurons using single electrode recordings to the interaction of thousands of neurons using fMRI. Data assimilation involves inverting a generative model that can not only explain observed data but also generate predictions. Typically, the model is inverted or fitted using conventional tools of (convex) optimization that invariably extremise some functional - norms, minimum descriptive length, variational free energy, etc. Generally, optimisation rests on evaluating the local gradients of the functional to be optimized. In this paper, we compare three different gradient estimation techniques that could be used for extremising any functional in time - (i) finite differences, (ii) forward sensitivities and a method based on (iii) the adjoint of the dynamical system. We demonstrate that the first-order gradients of a dynamical system, linear or non-linear, can be computed most efficiently using the adjoint method. This is particularly true for systems where the number of parameters is greater than the number of states. For such systems, integrating several sensitivity equations - as required with forward sensitivities - proves to be most expensive, while finite-difference approximations have an intermediate efficiency. In the context of neuroimaging, adjoint based inversion of dynamical causal models (DCMs) can, in principle, enable the study of models with large numbers of nodes and parameters.

Rotation Bounds for Hölder Continuous Homeomorphisms with Integrable Distortion.

We obtain sharp rotation bounds for the subclass of homeomorphisms f : C → C of finite distortion which have distortion function in L loc p , p > 1 , and for which a Hölder continuous inverse is available. The interest in this class is partially motivated by examples arising from fluid mechanics. Our rotation bounds hereby presented improve the existing ones, for which the Hölder continuity is not assumed. We also present examples proving sharpness.

Response to high LET radiation 12C (LET, 295 keV/microm) in M5 cells, a radio resistant cell strain derived from Chinese hamster V79 cells.

PURPOSE: To study the effects of 12C-beam of 295 keV/microm (57.24 MeV) on M5 and Chinese hamster V79 cells by using cytogenetic assays like micronuclei (MN) induction, chromosomal aberrations (CA) and apoptosis. Additionally, the relative survival of these two cell lines was tested by the colony forming ability of the cells, with a view to understanding the mechanism of cellular damages that lead to difference in cell survival. MATERIALS AND METHODS: Confluent cells were irradiated with 12C-beam at various doses using 15UD Pelletron accelerator. Cell survival was studied by the colony forming ability of cells. MN assay was done by fluorescent staining. Different types of chromosomal aberrations in metaphase cells were scored at 12 h after irradiation. Apoptosis was measured at different post irradiation times as detected by nuclear fragmentation and DNA ladder was prepared after 48 h of incubation. RESULTS: Dose-dependent decrease in surviving fractions was found in both the cell lines. However, the surviving fractions were higher in M5 cells in comparison to V79 cells when exposed to the same radiation doses. On the other hand, induced MN frequencies, CA frequencies and apoptosis percentages were less in M5 cells than V79 cells. Very good correlations between surviving fractions and induced MN frequencies or induced total CA or induced apoptosis percentages were obtained in this study. CONCLUSIONS: The cell strain M5 showed relatively more radio-resistance to 12C-beam compared to Chinese hamster V79 cells in this study. As the MN formation, CA and apoptosis induction were less in M5 cells as compared to parental V79 cells, the higher cell survival in the former could possibly be attributed to their better repairing ability leading to higher cell survival.

Lack of horizontal gene transfer of methicillin-resistance genetic determinants from PBP2a-positive, coagulase-negative staphylococci to methicillin-sensitive Staphylococcus aureus using transcutaneous electrical nerve stimulation (TENS).

Previous research shows that approximately half of the coagulase-negative staphylococci (CNS) isolated from patients in the intensive care unit (ICU) at Belfast City Hospital were resistant to methicillin. The presence of this relatively high proportion of methicillin-resistance genetic material gives rise to speculation that these organisms may act as potential reservoirs of methicillin-resistance genetic material to methicillin-sensitive Staphylococcus aureus (MSSA). Mechanisms of horizontal gene transfer from PBP2a-positive CNS to MSSA, potentially transforming MSSA to MRSA, aided by electroporation-type activities such as transcutaneous electrical nerve stimulation (TENS), should be considered. Methicillin-resistant CNS (MR-CNS) isolates are collected over a two-month period from a variety of clinical specimen types, particularly wound swabs. The species of all isolates are confirmed, as well as their resistance to oxacillin by standard disc diffusion assays. In addition, MSSA isolates are collected over the same period and confirmed as PBP2a-negative. Electroporation experiments are designed to mimic the time/voltage combinations used commonly in the clinical application of TENS. No transformed MRSA were isolated and all viable S. aureus cells remained susceptible to oxacillin and PBP2a-negative. Experiments using MSSA pre-exposed to sublethal concentrations of oxacillin (0.25 microg/mL) showed no evidence of methicillin gene transfer and the generation of an MRSA. The study showed no evidence of horizontal transfer of methicillin resistance genetic material from MR-CNS to MSSA. These data support the belief that TENS and the associated time/voltage combinations used do not increase conjugational transposons or facilitate horizontal gene transfer from MR-CNS to MSSA.

Profile of pediatric dengue cases from a tertiary care hospital in Kolkata.

A study was conducted on the 52 serologically positive cases of dengue, admitted to the Dept. of Paediatrics, R.G. Kar Medical College & Hospital, from an outbreak in Kolkata. The most unusual feature observed in this study was that the rash in some cases was urticarial and intensely pruritic. The shock appeared early in the course of the disease and it was less commonly associated with bleeding (22%). One out of three dengue cases was a severe disease. It was not possible to predict a severe disease from the early symptomatology.

Source apportionment of ambient VOCs in Delhi City.

Source apportionment using chemical mass balance (CMB) model was carried using a data set of 360 four hourly samples collected at 15 locations of five categories namely residential, commercial, industrial, traffic intersections and petrol pumps during August 2001-July 2002 in Delhi. The results indicate that emissions from diesel internal combustion engines dominate in Delhi. Vehicular exhaust and evaporative emissions also contribute significantly to VOCs in ambient air. Emission of VOCs associated with sewage sludge was also found to contribute to VOCs in Delhi's air. This points to the fact that open defecation and leaking sewage manholes are a problem in all categories of locations.

A study on the delivery practices in riverine & non-riverine blocks of the district of South 24-Parganas, West Bengal.

A cross sectional study was undertaken in three riverine and two non-riverine blocks of South 24 Parganas district, West Bengal to study the delivery practices and compare between two locality. During the reference period of one year, of 3073 total deliveries, 89.36% were home deliveries. Home deliveries were higher in the riverine blocks (95.07%) compared to non-riverine blocks (81.64%). 'Dai' conducted 58.36% and 90.62% of home deliveries in riverine and non-riverine blocks respectively. Only 18.4% of the 'Dai' were trained.

Study of Drug Resistant Pulmonary Tuberculosis.

BACKGROUND: Drug resistance has emerged as a major problem in management of pulmonary tuberculosis (PT) with increase in its incidence. METHODS: Sixty patients who presented to a tertiary referral chest centre with drug resistant PT were included in the study out of 835 clinically diagnosed cases of PT treated between January 2000 and May 2002. They were studied to see the incidence, pattern of drug resistance and response to treatment. RESULTS: 7.2% of the clinically diagnosed cases of PT had drug resistance and 14.8% of the 403 strains of mycobacterium tuberculosis (MTB) tested were resistant to one or more antitubercular drugs (ATD). 40 cases (66.7%) had initial resistance and acquired resistance was seen in 20(33.3%) out of the 60 cases of drug resistant PT. Single drug resistance was observed in 21 cases (35%), two drug resistance in 19 (31.7%) and 20(33.3%) cases showed resistance to three or more drugs. Individual drug resistance breakup was: INH(H) - 36(8.9%), Rifampicin (R)-38(9.4%), Ethambutol (E) - 14(3.5%), Streptomycin (S) - 34(8.4%), Pyrazinamide (Z) - 2(0.5%), Ciprofloxacin (C) - 2(0.5%), Ethionamide (N) - 2(0.5%), Cycloserine - 1(0.3%) and Kanamycin - 1(0.3%). 98.3% showed sputum conversion after starting reserve drugs. Average period of sputum conversion was 10 weeks. 3.3% were HIV positive. CONCLUSION: Incidence of drug resistance was not as high as reported by some other workers and majority of the cases showed satisfactory outcome.

Human immunodeficiency virus infection related to blood transfusion service.

The prevalence of transmissible viruses, human immunodeficiency (HIV) and hepatitis B (HBV) in blood donors, recipients and blood bank staff in a Calcutta (eastern India) based blood bank and transfusion centre has been studied from 1987-93. HIV seropositivity of blood donors was of recent emergence and was low. Recipients of blood and blood components frequently i.e., haemophilics showed a progressive increase in HIV seropositivity since 1988 whereas in thalassaemics the emergence of HIV seropositivity was noted only in 1992. Blood bank staff were seronegative. HBV which has a similar portal of entry as HIV, had a higher prevalence in blood donors, recipients of blood/components and blood bank staff.

Sero-surveillance of transmissible hepatitis B & C viruses in asymptomatic HIV infection in haemophilics.

In a group of 37 haemophilics, 9 (24.3%) were seropositive for human immunodeficiency virus (HIV), while 9 (24.3%) and 10 (27%) were positive for hepatitis B virus (HBV) and hepatitis C virus (HCV) respectively. Haemophilics who were HIV seropositive had higher prevalence of HBV and HCV. Seropositivity for HIV was more in patients with severe haemophilia A who required frequent factor VIII replacement. The need for long term surveillance of voluntary blood donors for transfusion associated viruses like HIV, HBV and HCV, is emphasized.

Intracervical application of prostaglandin E2 tablets for elective induction of labor in grand multiparae: a prospective controlled study.

In a prospective and controlled study labor was induced electively in 150 grand multiparae (GM) between 38 and 42 wk gestation by intracervical application of PGE2 tablets (induction group). Another 150 GM who went into labor spontaneously served as controls for comparison of labor characteristics and outcome (control group). In the induction group labor was successfully induced in 147 GM (98.0%), of whom 142 (96.5%) delivered vaginally. The mean duration of the active phase of labor was 2.1 +/- 0.79 h in GM who delivered on the first day of induction and 2.8 +/- 0.47 h in women who delivered on the second day, as compared to 4.7 +/- 2.2 h in the controls. Similarly, the mean duration of the second and third stage was longer in the controls. Operative deliveries were 2--3-times more frequent among controls, as were complications in the second and third stages. The group profiles of the I.U.P. charts indicating rise time, fall time, amplitude and Montevideo units at different stages of cervical dilatation showed significant differences at 4-5 cm dilatation only between the two groups of women. It is concluded that elective induction in GM between 38 and 42 wk is safe for mother and fetus.

Vulvar carcinoma in premenopausal Jamaican women.

Between the years 1958 and 1973, 119 patients with primary invasive cancer of the vulva were treated at the University Hospital of the West Indies, Kingston, Jamaica. Seventy-seven (64.7%) were premenopausal women. Because the pattern of the disease differed from that in late middle and older aged Jamaican women, the results of the disease are presented. The analysis stresses that vulvar carcinoma before menopause in our community is rare in the absence of various sexually transmitted granulomatous diseases of the vulva.

Carcinoma-in-situ of the cerivix treated with colposcopy guided epithelial conization. Report of a 4-7 year follow-up study.

Twenty-five patients with the diagnosis of carcinoma-in-situ (CIS) of the cervix were treated with colposcopy guided epithelial conization. During the follow-up study of 4-7 years' duration, there was no recurrence of CIS in 20 of the 25 patients. Between 6 and 12 months after conization, 3 patients showed recurrence of CIS. Two of these patients were treated with further epithelial conization with no evidence of further recurrence 4 years after the second treatment. The third patient refused to accept further epithelial conization and modified radical hysterectomy was done without any evidence of residual tumour in the hysterectomy specimen. One patient showed stromal invasion in both colposcopically guided biopsy and bone biopsy. Modified radical hysterectomy specimen showed remnants of stromal invasion. One patient with Class IV smear failed to show any atypical transformation zone and cervicitis was proven on colposcopy guided biopsy following treatment with Flagyl. For two of the 25 patients, cytology was Class II and therefore failed to diagnose the pre-malignant condition; but colposcopy showed a grade 3 atypical transformation zone and the presence of CIS was confirmed histologically. Simultaneous use of cytology, colposcopy and colposcopically guided biopsy confirmed the diagnosis of CIS in all cases. The authors recommend colposcopically guided epithelial conization in younger patients, provided the malignant lesion is strictly intra-epithelial, and limited to the ectocervix. Routine follow-up with the aid of cyto-colposcopy remains the key factor in this schedule of therapy.

Vaginal birth after cesarean section: management debate.

Obstetric performance of 1847 women with previous cesarean section (CS) during the years 1983 and 1984 were studied. Vaginal birth after cesarean section (VBAC) was attempted in 94% of females with one previous CS, 4% in those with two previous CS, and one among the 70 patients with three or more previous CS. VBAC was achieved in 51% of those with one previous CS. It was successful in 60% of parturients with CS for non-recurrent causes, 36% of CS for cephalopelvic disproportion (CPD) and in 64% of those with a prior vaginal delivery. Uterine scar dehiscence was found in 0.9% of all patients with a previous CS. A failed attempt with Ventouse to achieve VBAC caused maximum maternal and perinatal morbidity.

Myomectomy in infertile Jamaican women.

One hundred nineteen Jamaican women who underwent myomectomy from 1964 to 1969 were followed up for 5 to 9 years. Infertility was the most common presenting complaint. Preoperative hysterosalpingograms were performed on 61 patients and were abnormal for the majority of these patients. Surgery revealed submucous fibroids in 41 patients and pelvic inflammatory disease in 51 patients. The pregnancy rate following myomectomy was 18.5%, but successful outcomes occurred in only 9.2% of the cases. Pregnancy was unsuccessful for all patients who underwent both myomectomy and tuboplasty. Twenty-three patients had a recurrence of myoma, and 13 of these underwent subsequent hysterectomy.

Genital herpes simplex virus infections: laboratory confirmation in diverse patient groups.

The laboratory diagnosis of genital herpes simplex virus (HSV) infections in various patient groups with diverse clinical manifestations including asymptomatic pregnant women with history of genital herpes and in a high prevalence group consisting of male patients with recurring genital ulcerations is described. HSV was detected by conventional cell culture and also by a CPE-enhancement technique using human embryonic lung fibroblasts (MRC-5) and Vero cells with subsequent typing of isolate by HSV type-specific monoclonal antibodies. A definite improvement in HSV diagnosis was noted by the use of the CPE-enhancement technique with the reduction of turn-around time to 24 h at which 61.1% and 50% isolation rates were detected in MRC-5 cells in comparison to 38.9% and 16.6% by conventional cell culture in the high prevalence patient population and asymptomatic pregnant women, respectively. Delayed development of CPE and reduced isolation rates were detected using Vero cells. Follow-up sampling of subsequent episodes of genital ulcerations in those with history of recurrence but an initial negative cell culture result, increased the isolation rate substantially and enabled the confirmation of diagnosis of genital HSV infection.

Prophylactic antibiotic in elective gynaecological and obstetrical major surgery.

A prospective controlled study of 580 patients who underwent non-radical major gynaecological or obstetrical surgery examined the use of prophylactic antibiotics. The test group of patients (290) showed a significantly lower (P=0.01) incidence of the total complications and the non-infective complication rate as against those among controls (290). The duration of hospitalisation was significantly reduced for both vaginal and abdominal surgery in the test group of patients as against those in the controls. There was no evidence of increased incidence of bacterial resistance or superinfection. The authors recommend the use of prophylactic antibiotic on a short term basis (for a total duration of 4 days), commencing preoperatively to achieve a significant reduction in the infective postoperative morbidity and a shorter stay by the patients.

Salmonella septic abortion.

Two cases of salmonella septic abortion are reported as unusual focal manifestations of salmonellosis. The possible route of infection and the guidelines for its management are discussed.

Choriocarcinoma in Jamaica.

Fifty-two cases of choriocarcinoma were recorded in the Jamaica Cancer Registry for the parishes of Kingston and St. Andrew, giving an incidence of 1:7,384 live births. This is intermediate between figures reported for Western metropolitan populations and for Far Eastern countries. Clinicopathological studies on 26 cases treated at the University Hospital in Jamaica revealed that 65% followed either normal pregnancy or abortion. Choriocarcinoma following a normal pregnancy or occurring without a previous history of pregnancy carried a poorer prognosis than those with a preceding hydatidiform mole. Many patients had primary neurological manifestations. The overall prognosis was poor due to late presentation with disseminated metastases. Of the 26 patients, 15 died of the disease within two years and only six appeared for a six-year follow-up.