Study of Alteplase for Respiratory Failure in SARS-CoV-2 COVID-19: A Vanguard Multicenter, Rapidly Adaptive, Pragmatic, Randomized Controlled Trial

Background

Pulmonary vascular microthrombi are a proposed mechanism of COVID-19 respiratory failure. We hypothesized that early administration of tissue plasminogen activator (tPA) followed by therapeutic heparin would improve pulmonary function in these patients.

Research Question

Does tPA improve pulmonary function in severe COVID-19 respiratory failure, and is it safe?

Study Design and Methods

Adults with COVID-19-induced respiratory failure were randomized from May14, 2020 through March 3, 2021, in two phases. Phase 1 (n = 36) comprised a control group (standard-of-care treatment) vs a tPA bolus (50-mg tPA IV bolus followed by 7 days of heparin; goal activated partial thromboplastin time [aPTT], 60-80 s) group. Phase 2 (n = 14) comprised a control group vs a tPA drip (50-mg tPA IV bolus, followed by tPA drip 2 mg/h plus heparin 500 units/h over 24 h, then heparin to maintain aPTT of 60-80 s for 7 days) group. Patients were excluded from enrollment if they had not undergone a neurologic examination or cross-sectional brain imaging within the previous 4.5 h to rule out stroke and potential for hemorrhagic conversion. The primary outcome was Pao₂ to Fio₂ ratio improvement from baseline at 48 h after randomization. Secondary outcomes included Pao₂ to Fio₂ ratio improvement of > 50% or Pao₂ to Fio₂ ratio of ≥ 200 at 48 h (composite outcome), ventilator-free days (VFD), and mortality.

Results

Fifty patients were randomized: 17 in the control group and 19 in the tPA bolus group in phase 1 and eight in the control group and six in the tPA drip group in phase 2. No severe bleeding events occurred. In the tPA bolus group, the Pao₂ to Fio₂ ratio values were significantly (P < .017) higher than baseline at 6 through 168 h after randomization; the control group showed no significant improvements. Among patients receiving a tPA bolus, the percent change of Pao₂ to Fio₂ ratio at 48 h (16.9% control [interquartile range (IQR), –8.3% to 36.8%] vs 29.8% tPA bolus [IQR, 4.5%-88.7%]; P = .11), the composite outcome (11.8% vs 47.4%; P = .03), VFD (0.0 [IQR, 0.0-9.0] vs 12.0 [IQR, 0.0-19.0]; P = .11), and in-hospital mortality (41.2% vs 21.1%; P = .19) did not reach statistically significant differences when compared with those of control participants. The patients who received a tPA drip did not experience benefit.

Interpretation

The combination of tPA bolus plus heparin is safe in severe COVID-19 respiratory failure. A phase 3 study is warranted given the improvements in oxygenation and promising observations in VFD and mortality.

Trial Registry

ClinicalTrials.gov; No.: NCT04357730; URL: www.clinicaltrials.gov

Low Cardiac Output Syndrome: Incidence after Mitral Valve Replacement with or without Preservation of Mitral Valve Apparatus

Standard mitral valve replacement in patients with chronic mitral valve regurgitation and mitral valve stenosis consistently results in a decrease in early postoperative left ventricular ejection performance. Some studies showed that preservation of mitral valve leaflet and subvalvular apparatus can reduce postoperative left ventricular dysfunction. On the basis of the concept, this randomized clinical trial comparing mitral valve replacement with preservation of mitral subvalvular apparatus and conventional mitral valve replacement performed in National Institute of Cardiovascular Diseases (NICVD), Dhaka, Bangladesh, in the period of July 2010 to December 2011. We included 60 patients of mitral regurgitation and mitral stenosis, among them 30 patients underwent mitral valve replacement with preservation of mitral subvalvular apparatus (Group A) and 30 patients underwent conventional mitral valve replacement (Group B). There was no significant difference between two groups in terms of peri-operative variables. But there was significant higher incidence of Low cardiac output (LOS) syndrome [36.7% vs. 6.9% (p<0.05)] and congestive heart failure in Group B than Group A. The duration of ICU stay was also significantly higher in conventional mitral valve replacement group [113.23±11.30 hours vs. 96.23±20.02 (p=0.001)]. Additionally, there was significantly less fall of left ventricular ejection fraction in preservation of mitral subvalvular apparatus group [preop 65.27±5.45, at discharge 54.31±3.78, after 3 months 58.28±5.20 (p<0.0001)] than conventional group [preop 66.43±4.58, at discharge 46.43±3.87, after 3 months 46.55±3.63 (p<0.0001)]. In this study left ventricular ejection fraction was used as measure of left ventricular function. We postulate that, this relative preservation of left ventricular ejection fraction was likely the result of preservation of mitral subvalvular apparatus.

Effectiveness of a Transesophageal Echocardiography Course

BACKGROUND

Transesophageal echocardiography has important applications for the management of the critically ill patient. There is a need to develop effective training programs for the critical care community in acquiring skill at critical care transesophageal echocardiography.

OBJECTIVE

We studied the effectiveness of a 1-day simulation-based course that focused on the acquisition of skill in the performance of critical care transesophageal echocardiography.

METHODS

Learners received training in image acquisition with a transesophageal simulator and training in image interpretation in small group sessions. Skill at image acquisition and image interpretation was assessed at the beginning and at the completion of the course.

RESULTS

There were 27 learners who attended the course. Pre and post knowledge scores were 55 (19; mean [SD]) and 88 (9; P < .0005), respectively. Pre and post image acquisition scores were 3.6 (3.7) and 9.9 (0.3; P < .0001), respectively.

CONCLUSIONS

A 1-day course in critical care transesophageal echocardiography that combined case-based image interpretation with image acquisition training using a simulator improved technical skills and knowledge base.

Bronchoscopic lung cryobiopsy: An Indian association for bronchology position statement

BACKGROUND

Bronchoscopic lung cryobiopsy (BLC) is a novel technique for obtaining lung tissue for the diagnosis of diffuse parenchymal lung diseases. The procedure is performed using several different variations of technique, resulting in an inconsistent diagnostic yield and a variable risk of complications. There is an unmet need for standardization of the technical aspects of BLC.

METHODOLOGY

This is a position statement framed by a group comprising experts from the fields of pulmonary medicine, thoracic surgery, pathology, and radiology under the aegis of the Indian Association for Bronchology. Sixteen questions on various technical aspects of BLC were framed. A literature search was conducted using PubMed and EMBASE databases. The expert group discussed the available evidence relevant to each question through e-mail and a face-to-face meeting, and arrived at a consensus.

RESULTS

The experts agreed that patients should be carefully selected for BLC after weighing the risks and benefits of the procedure. Where appropriate, consideration should be given to perform alternate procedures such as conventional transbronchial biopsy or subject the patient directly to a surgical lung biopsy. The procedure is best performed after placement of an artificial airway under sedation/general anesthesia. Fluoroscopic guidance and occlusion balloon should be utilized for positioning the cryoprobe to reduce the risk of pneumothorax and bleeding, respectively. At least four tissue specimens (with at least two of adequate size, i.e., ≥5 mm) should be obtained during the procedure from different lobes or different segments of a lobe. The histopathological findings of BLC should be interpreted by an experienced pulmonary pathologist. The final diagnosis should be made after a multidisciplinary discussion. Finally, there is a need for structured training for performing BLC.

CONCLUSION

This position statement is an attempt to provide practical recommendations for the performance of BLC in DPLDs.

NUT (Nuclear Protein in Testis) Carcinoma: A Report of Two Cases With Different Histopathologic Features

NUT (nuclear protein in testis) carcinoma (NC) is an aggressive carcinoma characterized by rearrangements of the NUT gene on chromosome 15q14. Histologically, it is a poorly differentiated carcinoma composed of monotonous, medium-sized, round cells with scant amphophilic or eosinophilic cytoplasm. Foci of abrupt keratinization are often seen. In this report, we compare the morphology of 2 cases of NC. The first case shows characteristic features of uniform, round epithelioid cells admixed with foci of abrupt keratinization. The second case demonstrates nests of epithelioid-polygonal cells that appear to be loosely cribriform within a mucoid stroma. Although considered rare, the actual incidence of NC may be underestimated, as it is likely that many go undiagnosed because the morphology deviates from what is typical. Our report demonstrates that NC should always be considered in any case of an undifferentiated carcinoma and should not be excluded if typical histologic and immunohistochemical features of squamous differentiation are lacking.

Photo-peak area ratios for estimation of elemental concentration in aqueous solutions using prompt gamma measurements

The use of photo-peak area ratios are investigated for quantitative estimation of elements, particularly chlorine, in aqueous solutions using neutron induced prompt gamma measurements. A ratio of prompt gamma intensities avoids the need for estimating the incident total neutron fluence and is demonstrated for chlorine concentration estimation in NaCl solutions. Monte Carlo simulation results validated with experimental measurements support the present analysis. Use of several prompt gamma intensities instead of a single one improves the accuracy of the estimated results.

Primary Sclerosing Cholangitis in a Young Female

Primary sclerosing cholangitis (PSC) is a liver disease characterized by inflammation and fibrosis of both intrahepatic and extrahepatic bile ducts resulting in cholestasis. Due to nonspecific symptoms it is difficult to diagnose until complication arises. It is common in male and usually associated with other autoimmune diseases. Here, we report a case of PSC in a young female which was initially thought to be drug induced cholestasis without presence of any other autoimmunity.

Multilevel programming in Cu/NiO y /NiO x /Pt unipolar resistive switching devices

The application of a NiO y /NiO x bilayer in resistive switching (RS) devices with x > y was studied for its ability to achieve reliable multilevel cell (MLC) characteristics. A sharp change in resistance brought about by sweeping the voltage, along with an improved on/off ratio (>10(3)) and endurance (10(4)) were achieved in the bilayer structure as compared to the single NiO x layer devices. Moreover, it was found that nonvolatile and stable resistance levels, especially the multiple low-resistance states of Cu/NiO y /NiO x /Pt memory devices, could be controlled by varying the compliance current. All the multilevel resistance states of the Cu/NiO y /NiO x /Pt bilayer devices were stable for up to 500 consecutive dc switching cycles, as compared to the Cu/NiO x /Pt single layer devices. The temperature-dependent variation of the high and low resistance states of both the bilayer and single layer devices was further investigated to elucidate the charge conduction mechanism. Finally, based on a detailed analysis of the experimental results, comparisons of the possible models for RS in bilayer and single layer memory devices have also been discussed.

Neutron emission and dose distribution from natural carbon irradiated with a 12 MeV amu-1 12C5+ ion beam

Measured neutron energy distribution emitted from a thick stopping target of natural carbon at 0°, 30°, 60° and 90° from nuclear reactions caused by 12 MeV amu^-1 incident ¹²C⁵⁺ ions were converted to energy differential and total neutron absorbed dose as well as ambient dose equivalent H ^*(10) using the fluence-to-dose conversion coefficients provided by the ICRP. Theoretical estimates were obtained using the Monte Carlo nuclear reaction model code PACE and a few existing empirical formulations for comparison. Results from the PACE code showed an underestimation of the high-energy part of energy differential dose distributions at forward angles whereas the empirical formulation by Clapier and Zaidins (1983 Nucl. Instrum. Methods 217 489-94) approximated the energy integrated angular distribution of H ^*(10) satisfactorily. Using the measured data, the neutron doses received by some vital human organs were estimated for anterior-posterior exposure. The estimated energy-averaged quality factors were found to vary for different organs from about 7 to about 13. Emitted neutrons having energies above 20 MeV were found to contribute about 20% of the total dose at 0° while at 90° the contribution was reduced to about 2%.

Optimization of soybean processing into kinema, a Bacillus-fermented alkaline food, with respect to a minimum level of antinutrients

AIMS

Optimization of traditional processing of soybeans using response surface methodology (RSM) to achieve a minimum level of antinutritional factors (ANFs) in kinema.

METHODS AND RESULTS

Central composite rotatable designs were used to optimize the processing stages of kinema preparation. In each stage, the linear or quadratic effects of independent variables were significant in minimizing ANF levels. The predicted optimum condition for soaking was when the raw beans-water ratio was 1 : 10, and the soaking temperature, time and pH were 10°C, 20 h and 8·0 respectively. Here, tannins content (TC), phytic acid content (PAC) and trypsin inhibitor activity (TIA) decreased (P < 0·05). While haemagglutinating activity (HA) level remained unchanged (P < 0·05), total biogenic amines content (TBAC) increased. The optimum condition for cooking was optimally soaked beans-water ratio of 1 : 5, and cooking pressure and time were 1·10 kg cm(-2) and 20 min respectively. Here, TC, PAC, TIA and HA decreased (P < 0·05), but TBAC remained unchanged compared to optimally soaked beans. TC and HA went below the level of detection. The optimum condition for fermentation was obtained when inoculum load was 10(3) total cells g(-1) grits, and fermentation temperature and time were 37°C and 48 h respectively. Fermentation of optimally cooked beans caused a reduction (P < 0·05) of PAC. While TIA remained unchanged (P < 0·05), TBAC increased. In kinema, TC, PAC, TIA and HA decreased (P < 0·05) over raw beans by 100, 61, 71 and 100% respectively. Good agreement was observed between predicted values and experimental values.

CONCLUSIONS

The processing treatments significantly minimized the level of ANFs in soybeans.

SIGNIFICANCE AND IMPACT OF THE STUDY

RSM was successfully deployed to obtain the optimum condition for kinema-making with a minimum level of ANFs without impairing sensory attributes of the product. The results are useful for commercial production of kinema.

Selection of neutron-absorbing materials to improve the low-energy response of a Zr-based extended neutron monitor using Monte Carlo simulations

Monte Carlo simulations have been carried out using the FLUKA code to improve the neutron ambient dose equivalent [H*(10)] response of the ZReC (zirconium-lined portable neutron counter responding satisfactorily to neutrons up to 1 GeV) by introducing various neutron absorbers in the system such as cadmium, gadolinium, natural boron, enriched (10)B and borated polythene. It was found that ZReC can be effectively used as a portable neutron monitor by introducing any one of the following perforated layers: 5 mm thick natural boron, 0.5 mm thick enriched (10)B or 1 cm high-density polythene mixed with 50 % boron by weight. The integral response of the instrument was also calculated for some typical reference neutron fields. The relative ambient dose equivalent response of the said system is also found comparable with that of the existing LINUS neutron monitor.

Use of Bacillus subtilis isolates from Tua-nao towards nutritional improvement of soya bean hull for monogastric feed application

Soya bean hull (SBH) is a cheap and high-fibre content feed ingredient that obtained after soya bean oil extraction. Microbial fermentation was expected to improve SBH qualities before applying to animals, especially monogastric animals. Two bacterial strains, Bacillus subtilis MR10 and TK8 that were isolated from Tua-nao, a traditional fermented soya bean in northern Thailand, were used for fermented soya bean hull (FSBH) production. Both could easily grow at 37°C in SBH as the sole substrate. MR10 produced the highest β-mannanase activity (400 U g(-1) SBH) on day 2, while TK8 produced the highest cellulase activity (14·5 U g(-1) SBH) on day 3. After fermentation, the nutritional quality of SBH was obviously improved by an increase in soluble sugars, soluble proteins, crude protein and crude lipid, and a decrease in the content of raffinose family oligosaccharides. Scavenging activity (%) of SBH against ABTS radical cation was also increased from 14 to 27 and 20% by MR10 and TK8 fermentation, respectively. According to the GRAS property of these both strains and various improvements of nutritional values, the fermented SBH proved to be a potential feed ingredient, especially for the monogastric animals.

SIGNIFICANCE AND IMPACT OF THE STUDY

Normally, soya bean hull has been recognized as only a worthless by-product from soya bean oil production process because of its low utilizable nutrients. Our study introduced an alternative way to utilize this worthless residue using biotechnological knowledge. The nutritional quality of soya bean hull was improved by microbial fermentation. Fermented soya bean hull can be used as a cheap, safe and high-nutrient feed ingredient for livestock production, especially monogastric animals, to promote their growth performances, instead of using antibiotics in some regions of the world.

Bacillus fermentation of soybeans

Kinema fermentations of Indian and Canadian No. 1 soybeans by Bacillus sp. DK-W1 and by mixed cultures of Bacillus sp. DK-W1 and Enterococcus faecium DK-C1 were essentially identical. The viable cell count of Bacillus increased from an initial 10(5) to 10(10) c.f.u./g wet wt after 48 h incubation at 37°C. The pH of the fermentation dropped from an initial 6.9 to about 6.4 after 8 h and then rose to 8.6 after 32 h, with a coincident increase in proteolytic activity and ammonia concentration. The fermentations containing E. faecium and Bacillus exhibited a greater initial pH decline and a slightly retarded subseqent increase in pH compared with fermentations with Bacillus only. The presence of E. faecium had no detectable effects on growth of the Bacillus, proteolytic activity, ammonia production or the final pH of the fermentations.

Estimation of (41)Ar production in 0.1-1.1.0-GeV proton accelerator vaults using FLUKA Monte Carlo code

The FLUKA Monte Carlo simulations are carried out to estimate the (41)Ar concentration inside accelerator vaults of various sizes when proton beams of energy 0.1-1.0 GeV are incident on thick copper and lead targets. Generally (41)Ar concentration is estimated using an empirical formula suggested in the NCRP 144, which assumes the activation is caused only by thermal neutrons alone. It is found that while the analytical and Monte Carlo techniques give similar results for the thermal neutron fluence inside the vault, the (41)Ar concentration is under-predicted by the empirical formula. It is also found that the thermal neutrons contribute ∼41 % to the total (41)Ar production while 56 % production is caused by neutrons between 0.025 and 1 eV. A modified factor is suggested for the use in the empirical expression to estimate the (41)Ar activity 0.1-1.0-GeV proton accelerator enclosures.

Study of the transfer of 137Cs from fodder to cow milk in the region around Narora Atomic Power Station NPP Site, India

Site-specific transfer coefficient from feed to cow's milk, for (137)Cs in the villages around Narora, a nuclear power station site in India, determined over a period of 17 y, is presented in this paper. In the transport model for the prediction of the concentration of (137)Cs in milk, the transfer coefficient from feed to milk, Fm, is an important parameter. The transfer coefficient value is determined from (137)Cs concentration in milk and grass samples of the Narora region, and the result ranged from 4.28E-03 to 3.30E-02 d l(-1) with a geometric mean value of 1.15E-03 d l(-1). The highest and the lowest values were only below one order of magnitude different from the mean, regardless of the type of diet, milk yield and age of the cow. The result is compared with that for (40)K, determined concurrently at the same region and ranged from 6.92E-03 to 8.01E-03 d l(-1) with a geometric mean value of 7.45E-03 d l(-1). This parameter is quite useful in decision-making for implementing countermeasures during a large-area contamination with (137)Cs in tropical areas like Narora. The ingestion dose from fallout (137)Cs through milk intake for adult and child is also estimated.

Analysis of hydrological trend for radioactivity content in bore-hole water samples using wavelet based denoising

A wavelet transform based denoising methodology has been applied to detect the presence of any discernable trend in (137)Cs and (90)Sr activity levels in bore-hole water samples collected four times a year over a period of eight years, from 2002 to 2009, in the vicinity of typical nuclear facilities inside the restricted access zones. The conventional non-parametric methods viz., Mann-Kendall and Spearman rho, along with linear regression when applied for detecting the linear trend in the time series data do not yield results conclusive for trend detection with a confidence of 95% for most of the samples. The stationary wavelet based hard thresholding data pruning method with Haar as the analyzing wavelet was applied to remove the noise present in the same data. Results indicate that confidence interval of the established trend has significantly improved after pre-processing to more than 98% compared to the conventional non-parametric methods when applied to direct measurements.

Monte Carlo simulation of embedded 241Am activity in injured palm

This paper describes a methodology to estimate embedded activity of (241)Am and Pu isotopes in a wound at an unknown depth. Theoretical calibration of an array of high-purity germanium detectors is carried out using the Monte Carlo code 'FLUKA' for a (241)Am source embedded at different depths in a soft tissue phantom of dimension 10 × 10 × 4 cm(3) simulating the palm of a worker. It is observed that, in the case of contamination due to pure (241)Am, the ratio of counts in 59.5 and 17.8 keV (Ratio 1) should be used to evaluate the depth, whereas the ratio of counts in 59.5 and 26.3 keV (Ratio 2) should be used when the contamination is due to a mixture of Pu and (241)Am compounds. Variations in the calibration factors (CFs) as well as in the Ratio 1 and Ratio 2 values are insignificant when source dimensions are varied from a point source to a 15-mm diameter circle. It is observed that tissue-equivalent polymethyl methacrylate material can be used in the phantom to estimate the embedded activity, when the activity is located at a depth of <1 cm, as the corresponding CFs do not show much variation with respect to those estimated using the phantom containing soft tissue material. In all other cases, an appropriate soft tissue-equivalent material should be used in the phantom for the estimation of CFs and ratios. The CFs thus obtained will be helpful in an accurate estimation of the depth of the wound and the activity embedded therein in the palm of a radiation worker.

Spectral information enhancement using wavelet-based iterative filtering for in vivo gamma spectrometry

Use of wavelet transformation in stationary signal processing has been demonstrated for denoising the measured spectra and characterisation of radionuclides in the in vivo monitoring analysis, where difficulties arise due to very low activity level to be estimated in biological systems. The large statistical fluctuations often make the identification of characteristic gammas from radionuclides highly uncertain, particularly when interferences from progenies are also present. A new wavelet-based noise filtering methodology has been developed for better detection of gamma peaks in noisy data. This sequential, iterative filtering method uses the wavelet multi-resolution approach for noise rejection and an inverse transform after soft 'thresholding' over the generated coefficients. Analyses of in vivo monitoring data of (235)U and (238)U were carried out using this method without disturbing the peak position and amplitude while achieving a 3-fold improvement in the signal-to-noise ratio, compared with the original measured spectrum. When compared with other data-filtering techniques, the wavelet-based method shows the best results.

Finding an alternative diagnosis does not justify increased use of CT-pulmonary angiography

Background

The increased use of computed tomography pulmonary angiography (CTPA) is often justified by finding alternative diagnoses explaining patients’ symptoms. However, this has not been rigorously examined.

Methods

We retrospectively reviewed CTPA done at our center over an eleven year period (2000 – 2010) in patients with suspected pulmonary embolus (PE). We then reviewed in detail the medical records of a representative sample of patients in three index years – 2000, 2005 and 2008. We determined whether CTPA revealed pulmonary pathology other than PE that was not readily identifiable from the patient’s history, physical examination and prior chest X-ray. We also assessed whether the use of pre-test probability guided diagnostic strategy for PE.

Results

A total of 12,640 CTPA were performed at our center from year 2000 to 2010. The number of CTPA performed increased from 84 in 2000 to 2287 in 2010, a 27 fold increase. Only 7.6 percent of all CTPA and 3.2 percent of avoidable CTPAs (low or intermediate pre-test probability and negative D-dimer) revealed previously unknown findings of any clinical significance. When we compared 2008 to 2000 and 2005, more CTPAs were performed in younger patients (mean age (years) for 2000: 67, 2005: 63, and 2008: 60, (p=0.004, one–way ANOVA)). Patients were less acutely ill with fewer risk factors for PE. Assessment of pre-test probability of PE and D-dimer measurement were rarely used to select appropriate patients for CTPA (pre-test probability of PE documented in chart (% total) in year 2000: 4.1%, 2005: 1.6%, 2008: 3.1%).

Conclusions

Our data do not support the argument that increased CTPA use is justified by finding an alternative pulmonary pathology that could explain patients’ symptoms. CTPA is being increasingly used as the first and only test for suspected PE.

Estimation of specific absorbed fractions for selected organs due to photons emitted by activity deposited in the human respiratory tract using ICRP/ICRU male voxel phantom in FLUKA

The ICRP/ICRU adult male reference voxel phantom incorporated in Monte Carlo code FLUKA is used for estimating specific absorbed fractions (SAFs) for photons due to the presence of internal radioactive contamination in the human respiratory tract (RT). The compartments of the RT, i.e. extrathoracic (ET1 and ET2) and thoracic (bronchi, bronchioles, alveolar interstitial) regions, lymph nodes of both regions and lungs are considered as the source organs. The nine organs having high tissue weighting factors such as colon, lungs, stomach wall, breast, testis, urinary bladder, oesophagus, liver and thyroid and the compartments of the RT are considered as target organs. Eleven photon energies in the range of 15 keV to 4 MeV are considered for each source organ and the computed SAF values are presented in the form of tables. For the target organs in the proximity of the source organ including the source organ itself, the SAF values are relatively higher and decrease with increase in energy. As the distance between source and target organ increases, SAF values increase with energy and reach maxima depending on the position of the target organ with respect to the source organ. The SAF values are relatively higher for the target organs with smaller masses. Large deviations are seen in computed SAF values from the existing MIRD phantom data for most of the organs. These estimated SAF values play an important role in the estimation of equivalent dose to various target organs of a worker due to intake by inhalation pathway.

Evaluation of internal dose to members of the public at the Kaiga site, India, due to the ingestion of primordial radionuclide 40K

Four 220 MWe pressurised heavy water reactors are under operation at Kaiga in the state of Karnataka in India. Environmental radiological survey of the surrounding areas of the Kaiga site is carried out by Bhabha Atomic Research Centre, Mumbai. The estimated dose to the members of the public due to ingestion of radioactive isotope of potassium, a natural radionuclide, in the surroundings of the Kaiga site is 136 μSv (13.6 mrem) per year. The value indicates that the dose to the public due to operation of the nuclear reactors in Kaiga is insignificant in comparison with the dose due to unavoidable natural radioactivity.

Effect of shodhana treatment on chronic toxicity and recovery of aconite

Aconite is one of the poisonous plants used therapeutically in practice of Ayurveda after proper treatment called as ‘Shodhana’. To determine the effect of Shodhana treatment on chronic toxicity and to assess the effect of recovery period after chronic toxicity of aconite. Raw aconite (RV), urine treated aconite (SM), and milk treated aconite (SD) were administered in 6.25 mg/kg dose in Charles Foster strain albino rats for 90 days for chronic toxicity. Six rats from each were kept for another 30 days without test drugs treatment to observe recovery from chronic toxicity. RV was found to be highly toxic in chronic exposure, SM had no apparent toxicity, but SD had mild toxicity in kidney. The toxicities of RV and SD were reversible, but sudden withdrawal of SM caused adverse effects, suggestive of tapering withdrawal. Shodhana treatments remove toxic effects from raw aconite. Chronic toxicity of aconite is reversible. Confirmed the arrangement of abstract

Detection of low level gaseous releases and dose evaluation from continuous gamma dose measurements using a wavelet transformation technique

Measurement of environmental dose in the vicinity of a nuclear power plant site (Tarapur, India) is carried out continuously for the years 2007-2010 and attempts have been made to quantify the additional contributions from nuclear power plants over natural background by segregating the background fluctuations from the events due to plume passage using a non-decimated wavelet approach. A conservative estimate obtained using wavelet based analysis has shown a maximum annual dose of 38 μSv in a year at 1.6 km and 4.8 μSv at 10 km from the installation. The detected events within a year are in good agreement with the month wise wind-rose profile indicating reliability of the algorithm for proper detection of an event from the continuous dose rate measurements. The results were validated with the dispersion model dose predictions using the source term from routine monitoring data and meteorological parameters.

Transfer coefficient of 137Cs from feed to cow milk in tropical region Kaiga, India

In the transport model for the prediction of the concentration of (137)Cs in milk, the transfer coefficient from feed to milk, F(m), is an important parameter. Site-specific transfer coefficient from feed to cow's milk, for (137)Cs in the Kaiga environment, a nuclear power station site in India, determined over a period of 10 y is presented in this paper. The value is determined from (137)Cs concentration in milk and grass samples of the Kaiga region and the result ranged from 6.43E-03 to 1.09E-02 d l(-1) with a geometric mean value of 8.0E-03 d l(-1). The result is compared with that for (40)K, determined concurrently at the same region and ranged from 3.06E-03 to 3.48E-03 d l(-1) with a geometric mean value of 3.26E-03 d l(-1). This parameter is quite useful in decision-making for implementing countermeasures during a large area contamination with (137)Cs in tropical areas like Kaiga.

Environmental transportation of tritium and estimation of site-specific model parameters for Kaiga site, India

Tritium content in air moisture, soil water, rain water and plant water samples collected around the Kaiga site, India was estimated and the scavenging ratio, wet deposition velocity and ratio of specific activities of tritium between soil water and air moisture were calculated and the results are interpreted. Scavenging ratio was found to vary from 0.06 to 1.04 with a mean of 0.46. The wet deposition velocity of tritium observed in the present study was in the range of 3.3E-03 to 1.1E-02 m s(-1) with a mean of 6.6E-03 m s(-1). The ratio of specific activity of tritium in soil moisture to that in air moisture ranged from 0.17 to 0.95 with a mean of 0.49. The specific activity of tritium in plant water in this study varied from 73 to 310 Bq l(-1). The present study is very useful for understanding the process and modelling of transfer of tritium through air/soil/plant system at the Kaiga site.

Studies on the rain scavenging process of tritium in a tropical site in India

This study presents the results of one of the first systematic experiments on tritium ((3)H) concentrations in ground level air against that in rainwater near a pressurized heavy water reactor in a tropical region. The samples were collected over the rainy season of three years (2007, 2008 and 2010). For this study, 31 data sets were collected and interpreted based on the theoretical information available in the literature. The specific activity ratio of (3)H between rainwater and air moisture at ground level was calculated for each data set. The average specific activity ratio was found to be 1.96 ± 2.72. A correlation (r = 0.82, p < 0.001) was observed between the total rain hours in a day and the rainwater (3)H activity. Higher rain duration with slower rain rate yielded higher (3)H concentrations as more time was available for the scavenging/wash out process to take effect together with lower dilution. The present data also suggested the need to further investigate the influence of raindrop distribution and other local meteorological parameters on the (3)H wash out process. An attempt was also made to predict the (3)H concentration in air moisture samples using a Gaussian plume dispersion model and the values were compared with the measured (3)H activity. The measured values were generally lower than the predictions.

Soil to leaf transfer factor for the radionuclides ²²⁶Ra, ⁴⁰K, ¹³⁷Cs and ⁹⁰Sr at Kaiga region, India

Transfer factors are the most important parameters required for mathematical modeling used for environmental impact assessment of radioactive contamination in the environment. In this paper soil to leaf transfer factor for the radionuclides ⁴⁰K, ²²⁶Ra, ¹³⁷Cs and ⁹⁰Sr is estimated for Kaiga region in Karnataka state, India. Among the plants in which study is carried out, ²²⁶Ra, ⁴⁰K, ¹³⁷Cs and ⁹⁰Sr activity in leaves of herbaceous plants is higher than that of tree leaves. Soil to leaf transfer factor for ²²⁶Ra, ⁴⁰K, ¹³⁷Cs and ⁹⁰Sr was found to be in the range of 0.03-0.65, 0.32-8.04, 0.05-3.03 and 0.42-2.67 respectively.

Selected organ dose conversion coefficients for external photons calculated using ICRP adult voxel phantoms and Monte Carlo code FLUKA

The adult reference male and female computational voxel phantoms recommended by ICRP are adapted into the Monte Carlo transport code FLUKA. The FLUKA code is then utilised for computation of dose conversion coefficients (DCCs) expressed in absorbed dose per air kerma free-in-air for colon, lungs, stomach wall, breast, gonads, urinary bladder, oesophagus, liver and thyroid due to a broad parallel beam of mono-energetic photons impinging in anterior-posterior and posterior-anterior directions in the energy range of 15 keV-10 MeV. The computed DCCs of colon, lungs, stomach wall and breast are found to be in good agreement with the results published in ICRP publication 110. The present work thus validates the use of FLUKA code in computation of organ DCCs for photons using ICRP adult voxel phantoms. Further, the DCCs for gonads, urinary bladder, oesophagus, liver and thyroid are evaluated and compared with results published in ICRP 74 in the above-mentioned energy range and geometries. Significant differences in DCCs are observed for breast, testis and thyroid above 1 MeV, and for most of the organs at energies below 60 keV in comparison with the results published in ICRP 74. The DCCs of female voxel phantom were found to be higher in comparison with male phantom for almost all organs in both the geometries.

Directional distribution of the ambient neutron dose equivalent from 145-MeV ¹⁹F projectiles incident on thick Al target

The directional distribution of the ambient neutron dose equivalent from 145-MeV (19)F projectiles bombarding a thick aluminium target is measured and analysed. The measurements are carried out with a commercially available dose equivalent meter at 0°, 30°, 60° and 90° with respect to the beam direction. The experimental results are compared with calculated doses from EMPIRE nuclear reaction code and different empirical formulations proposed by others. The results are also compared with the measured data obtained from an earlier experiment at a lower projectile energy of 110 MeV for the same target-projectile combination.

Estimation of site-specific deposition velocities and mass interception factor using 7Be and the prediction of deposition pattern of radionuclides at Kaiga site, India

Site-specific wet, dry deposition velocities and mass interception factors at Kaiga site, where three PHWR type power plants are operational, using 7Be as a tracer are presented. Mean wet and dry deposition velocities for Kaiga site were found to be 7.4 x 10(-2) m s(-1) and 3.0 x 10(-4) m s(-1), respectively. Mass interception factors for vegetation were found to be 0.7-5.6 m(2) kg(-1) dry weight with a mean of 2.4 m(2) kg(-1) dry weight. The site-specific data were used for the prediction of radionuclide distribution pattern in soil and vegetation in the case of a hypothetical air contamination.

Degradation dynamics of chlorfenapyr residue in chili, cabbage and soil

Chlorfenapyr is a pyrrole group of insecticide, [4-bromo-2-(4-chlorophenyl)-1-ethoxymethyl-5-trifluoromethyl-1H-pyrrole-3-carbonitrile]used as broad spectrum insecticide/acaricide to control whitefly, thrips, caterpillars, mites, leafminers, aphids, etc., chlorfenapyr 10% SC formulation was applied on chili and cabbage twice @ 75 and 100 g a.i./ha along with untreated control. Chlorfenapyr was dissipated in chili, cabbage and soil following the first-order kinetics (logC/C(0) = -kt). The half lives of chlorfenapyr in chili, cabbage and soil were varying from 2.93 to 2.96 days, 2.98 to 3.62 days and 4.06 to 4.36 days respectively, according to the application rate.

Critical care aspects of malaria

Malaria remains a major health problem in much of Asia and Africa. A steady number of cases of imported malaria are also seen in many countries of the developed world. Plasmodium falciparum malaria and to some extent malaria caused by other species of Plasmodium can lead to many complications such as acute respiratory distress syndrome (ARDS), cerebral malaria, acute renal failure, severe anemia, thrombocytopenia, and bleeding complications. About 10% of patients with severe malaria die, usually as a result of multiorgan dysfunction. Critical care physicians should be aware of the complications and management of severe malaria. There has been significant progress in the understanding of pathogenesis of severe malaria over the last decade. Effective management of severe malaria includes early suspicion, prompt diagnosis, early institution of appropriate antimalarial chemotherapy, and supportive care, preferably in an intensive care unit. In this article, we review the different manifestations of severe malaria as relevant to critical care physicians and discuss the principles of laboratory diagnosis and management.

Toxicity and recovery studies of two ayurvedic preparations of iron

Lauha Bhasma and Mandura Bhasma in 55 mg/kg dose (5 times the therapeutic effective dose) for 60 days exhibited no serious toxic effects in Charles Foster albino rats. Both the drugs showed significant recovery from chronic toxic effect after 45 days of recovery period.

Direction distribution of ambient neutron dose equivalent from 20 MeV protons incident on thick Be and Cu targets

Ambient neutron dose equivalent from 20 MeV protons incident on thick Be and Cu targets are measured at 0 degrees, 30 degrees, 60 degrees and 90 degrees with respect to the beam direction using a conventional dose equivalent meter. The neutron spectra calculated using nuclear reaction model codes ALICE, PRECO and earlier reported empirical expressions are converted to the ambient dose equivalent using the ICRP fluence-to-dose conversion coefficients and are compared with the measured values. The experimental energy spectra reported in the literature for 19.08 MeV protons incident on a thick Be target are also converted to ambient neutron dose equivalent and are compared with the present experimental results. It is observed that the values estimated from the neutron spectra obtained from the nuclear reaction codes are unable to predict the measured values. The results obtained from the reported experimental energy spectra compare well with the results obtained here. An empirical relation that was used to calculate the directional dependence of the measured neutron dose equivalent from heavy ion-induced reactions is used in this study to check its effectiveness for proton-induced reactions.

Posterior reversible encephalopathy syndrome (PRES) in pregnancy: a diagnostic challenge to obstetricians

Post-partum clinical presentation with seizures and focal neurological deficit has a wide differential diagnosis. Two cases of the rare condition Posterior Reversible Encephalopathy Syndrome (PRES) associated with pregnancy are presented with complete recovery following multidisciplinary care. One of the cases was associated with Factor VII deficiency in pregnancy and the other with twin gestation and psoas abcess.

A prospective study of the correlation between genital pathogens and morbidity following diathermy loop excision of the transformation zone

A prospective study of 48 women was carried out to estimate the incidence of common genital pathogens in women referred to colposcopy clinic requiring diathermy loop excision and to compare patient morbidity in the subgroups with and without genital pathogens. Of the 43 women included in the analysis, genital pathogens were present in 24 cases (56%) and absent in 19 (44%) of the 24 positive cases, 19 (79%) women had pathogen(s) on the cervical swab, 24 (100%) had pathogen(s) on the high vaginal swab and 15 (63%) had both a positive cervical and high vaginal swab (HVS). The most frequently isolated groups of organisms were mixed anaerobes, alone (four HVS and four cervical) or in combination with Gardnerella vaginalis (four HVS and three cervical) or coliforms (two HVS and two cervical). The mean duration of bleeding and vaginal discharge in the two study groups was not statistically significant (t value 1.97, P 0.05; and t value 0.48, P 0.5, respectively). However, the mean duration of bleeding graded by the patient as being moderate to severe was significantly different in the two groups (t value 3.18 P 0.01). Fifty-six per cent of the women in the study had confirmed genital pathogens, predominantly anaerobes, and the prolonged moderate-to-severe bleeding in this group suggests a potential role for prophylactic bacteriocides, although the study size was unable to implicate a single pathogen.

Pulmonary manifestations of primary Sjögren's syndrome

Sjögren's syndrome (SS) is a complex autoimmune exocrinopathy with multifactorial pathogenesis and multisystem manifestation. It is called primary Sjögren's syndrome (PSS) when the manifestations are seen without any other co-existent rheumatic diseases. The incidence of respiratory system involvement varies widely in the reported medical literature, partly due to lack of a universal agreement over the diagnostic criteria of the disease and the type of study methods employed. Respiratory system manifestations are protean; upper airway symptoms are very common and so is the complaint of dry cough. The PSS patients may develop interstitial lung diseases (ILDs) such as usual interstitial pneumonia (UIP), non-specific interstitial pneumonia (NSIP), lymphocytic interstitial pneumonia (LIP), bronchiolitis obliterans and organising pneumonia (BOOP), etc. They may also develop the whole spectrum of lymphoproliferative disorders of the lung ranging from LIP to follicular bronchiolitis, nodular lymphoid hyperplasia and low-grade lymphomas. Therapeutic options include symptomatic and supportive measures and corticosteroids as the mainstay of the treatment for ILDs occurring in these patients. In recent years, rituximab (anti-CD20) has emerged as a promising treatment for this disease, though data from controlled trials are still lacking. Pulmonary involvement may be a source of significant morbidity in these patients, though only rarely, it is the cause of death.

Light charged particle emission from neutron and alpha-induced reactions

Emissions of protons and alpha-particles from neutron and alpha-induced reactions have been estimated using two nuclear reaction model codes ALICE91 and PRECO-2000. Calculated results have been compared with available energy differential and double differential emission cross sections from experimental measurements. Analysis of the data based on different nuclear reaction mechanisms revealed the relative importance of these mechanisms as well as predictive capabilities of the codes used. These results are useful in accelerator-driven systems, radioactive ion beam facilities and space dosimetry.

Compliance with the RCOG's guidelines on medical record keeping in female sterilisation: a complete audit cycle

Female sterilisation is a major cause of litigation, accounting for 25% of all claims notified to the Medical Defence Union, suggesting that the practice surrounding female sterilisation is less than perfect. Inadequate documentation has been identified as the major cause for complaints and litigation. RCOG published guidelines have emphasised the need for adequate documentation during preoperative counselling. This retrospective audit was carried out with the primary objective to determine whether RCOG's guidelines had been adhered to. Failure to comply with the RCOG guidelines in our study highlights the fact that awareness of published guidelines may not be enough to improve the quality of documentation. This evidence would strongly support the use of a standardised proforma that would improve the quality of documentation during preoperative counselling.