Estimating the mineral density of trabecular bone using Compton scattering.

This study proposes a technique based on Compton scattering to estimate trabecular bone mineral density (TBMD), which is important for understanding bone strength, and hence, is pivotal for estimating the condition of the bone. Bone phantoms (a mixture of paraffin wax and bone powder) with various concentrations of bone ash were prepared to simulate the trabecular bone. These samples were exposed to primary gamma photon flux from a137Cs (222 GBq) radioisotope source one after the other, and the scattered photon flux was detected using an NaI(Tl) detector. The presence of the cortical bone (using aluminum sheets) and fat (tertiary butyl alcohol) around the trabecular bone was also studied to determine whether the TBMD measurements had been affected. The correlation between bone ash contents and the intensity of Compton scattering was high with a coefficient of 0.97. The outcomes suggest that TBMD is independent of the presence of the cortical bone and overlying fat, with a statistical uncertainty of ±0.3% in the count rate. The intensity of Compton scattering increased by only 1.5% when the thickness of the aluminum sheet (simulating the cortical bone) becomes was increased by four times, and by less than 5% when the bone phantom was surrounded by tertiary butyl alcohol.

Comparative evaluation of various diagnostic techniques for detection of Cryptosporidium infection from the faecal samples of diarrhoeic bovine calves.

Background: Cryptosporidium, an opportunistic, zoonotic, apicomplexan parasite, is one of the most common causes of diarrhea in neonatal bovine calves around the globe. Bovine calves act as a major source of infection by excreting huge numbers of highly resistant oocysts in faeces, which can survive for a long time in extreme environmental conditions. As low as ten oocysts can cause disease and mortality, leading to the requirement of an early and accurate diagnosis for proper and favorable prognosis, management, and control. Aims: The current study was conducted with the objective to evaluate various diagnostic techniques (acid fast staining, negative staining, fluorescent, ELISA, PCR, nested PCR, and qPCR) for the detection of Cryptosporidium in the faecal samples of diarrheic bovine calves. Methods: Two hundred diarrheic faecal samples from bovine calves were collected and subjected to these techniques for Cryptosporidium diagnosis. Results of these were evaluated for diagnostic comparison. Results: Out of 200 faecal samples evaluated, 24% (48/200) were detected positive for Cryptosporidium using a combination of two techniques as gold standard criteria. Cohen's kappa value indicated moderate to almost perfect agreement (0.616 to 0.986) among all the techniques used in the present study. Leishman staining showed the lowest sensitivity (54.17%), while nested PCR and qPCR showed the highest sensitivity (97.92%). Diagnostic specificity of all these tests ranged from 98.68 to 100%. Conclusion: Auramine stain was used for the first time in the bovine calves in India for the detection and diagnostic comparison of Cryptosporidium. It showed strong agreement with the molecular as well as classical diagnostic techniques, and can be used for primary screening for better diagnosis.

Comparative study for intermediate crystal size of NaI(Tl) scintillation detector.

The distinctive features of a well-known NaI(Tl) scintillation detector, by virtue of its crystal size, are experimentally investigated by observing changes in parameters such as intrinsic efficiency (εi), photo-peak efficiency (εp), resolution, and response function to incident gamma photon energy. This study provides a better understanding for the choice of crystal size of the scintillation detector in Compton scattering experiments. The response function of the NaI(Tl) detector is in the form of an inverse matrix focusing on the retort of the crystal when gamma photons are incident upon it. The response function of the NaI(Tl) detector depends upon the distance between the source and the detector, composition of the material for the crystal itself, photo-fraction, solid angle, incident gamma energy, and geometry of the experimental setup. The factors responsible for broadening of full energy and backscattered peaks are discussed for present investigations. The observed results indicate that the resolution of the detector varies with the incident energy of gamma radiation, and it also depends upon the size of the crystal of the detector. Statistical fluctuations related with the scintillation mechanism are found to be responsible for broadening of instrumental line width (photo-peak). The signal-to-noise ratio and photo-fraction for different crystal sizes of the scintillation detector corrected for efficiency of the detector are also discussed.

Rates and determinants of antibiotics and probiotics prescription to children in Asia-Pacific countries.

Antibiotic therapy may have important side effects. Guidelines recommend the administration of specific probiotics to reduce the risk of antibiotic-associated diarrhoea (AAD). The rates and determinants of antibiotics and co-prescription of probiotics in children remain poorly known in Asia-Pacific countries, which are very heterogenous in terms of economic development, health care organization and health policies. A survey among general practitioners (GPs) and paediatricians was performed in seven countries of the Asia-Pacific area (Australia, Japan, Indonesia, India, China, Singapore, and South Korea). Physicians completed an online questionnaire that explored their current habits and the determinants for prescribing antibiotics and probiotics. For the 731 physicians who completed the questionnaire (390 paediatricians and 341 GPs), 37% of all consultations for a child led to the prescription of antibiotics (ranging from 17% in Australia to 47% in India). A large majority of physicians (84%) agreed that antibiotics disrupted gut microbiota and considered probiotics an effective intervention to prevent AAD (68%). However, only 33% co-prescribed probiotics with antibiotics (ranging from 13% in Japan to 60% in South Korea). The main reasons for prescribing probiotics were previous episodes of AAD (61%), presence of diarrhoea (55%), prolonged antibiotic treatment (54%) or amoxicillin-clavulanic acid therapy (54%). Although current local guidelines recommend the use of selected probiotics in children receiving antibiotics in Asia-Pacific area, the rates of antibiotics and probiotics prescription significantly vary among countries and are deeply affected by country-related cultural and organisational issues.

Exploring animal rabies endemicity to inform control programmes in Punjab, India.

Previous studies estimate that one-third of the annual global burden of rabies (~20,000 cases) occurs in India. Elimination of canine rabies is essential to reduce this burden. Surveillance of animal cases can assess both the risk to humans and the efficacy of control strategies. The objective of this study was to describe the spatial and temporal occurrence of reported confirmed cases of rabies in animals in Punjab, India, from 2004 to 2014. We analysed passive surveillance data on 556 samples submitted from 2004 to 2014 to GADVASU, Ludhiana, Punjab, India. Regression and time series analyses were conducted to understand seasonal and long-term variation of cases and identify cross-correlation of monthly cases between species. Spatio-temporal analyses assessed spatial autocorrelation of date of reporting, mean geographic centres of disease occurrence and clustering of cases using Kulldorff's space-time permutation statistic. The annual number of submissions and proportion of confirmed cases were consistent throughout 2004-2014. Most submissions (320; 57.6%) were confirmed rabies cases, including dogs (40.6%), buffalo (29.7%) and cattle (23.1%). Regression analysis of monthly cases in dogs showed seasonal variation with significant increases in cases in March and August. Monthly case numbers in buffalo decreased over time. Long-term temporal trend was not detected in dog and cattle cases. Time-series models identified significant cross-correlation between dog and buffalo cases, suggesting that buffalo cases were spillover events from dogs. Significant spatio-temporal variation or clusters of cases were not detected. These results indicate that rabies cases in animals-and therefore, the potential for exposure to humans-were temporally and spatially stable during 2004-2014 in Punjab, India. The endemic nature of rabies transmission in this region demands a coordinated, sustained control programme. This study provides baseline information for assessing the efficacy of rabies control measures and developing seasonally targeted dog vaccination and rabies awareness strategies.

Non-destructive study of wood using the Compton scattering technique.

A simple nondestructive method is presented in this study to characterize woods having different densities, thus estimating the size and depth of inhomogeneities in given wood samples using the Compton scattering technique (CST). This technique uses a collimated beam of 662-keV energy from 137Cs radioactive source, and the scattered flux is detected by an NaI(Tl) detector. To characterize different wood samples on the basis of their densities, both scattering and transmission experiments were performed. The presence of inhomogeneities such as knots in wood was simulated by drilling cylindrical voids of diameter 9mm in the samples and then filling them with a high-density material (aluminum). Furthermore, different sizes of inhomogeneities (Al cylinders) were filled in the wood samples to estimate the depth and size of the inhomogeneity using the CST. A higher linear correlation (R2 ~ 0.96) was found between the scattered intensity and the density of different woods using the CST than that using the transmission (R2 ~ 0.83) method by measuring the density range. An increase of 24.6% in the average scattered intensity was observed at the location where the knot was present, and it was found that an inhomogeneity of the order of ~4mm or more could be detected by the CST.

Periurban outbreaks of bovine calf scours in Northern India caused by Cryptosporidium in association with other enteropathogens.

Bovine calf scours reported to be caused by multiple aetiologies resulting in heavy mortality in unweaned calves and huge economic loss to the dairy farmers. Among these, cryptosporidiosis is an emerging waterborne zoonoses and one of the important causes of neonatal calf diarrhoea. Poor immune response coupled with primary cryptosporidial infections predispose neonatal calves to multiple secondary infections resulting in their deaths. In the present study, faecal samples from 100 diarrhoeic calves randomly picked up out of 17 outbreaks of bovine calf diarrhoea in periurban Ludhiana, Punjab in Northern India were subjected to conventional (microscopy, modified Zeihl-Neelsen (mZN) staining) and immunological and molecular techniques (faecal antigen capture ELISA and PCR) for detection of primary Cryptosporidium parvum infection as well as other frequently reported concurrent pathogens, viz. rotavirus and coronavirus, Salmonella spp., Escherichia coli, Clostridium perfringens and Eimeria spp. The faecal antigen capture ELISA and PCR revealed 35% prevalence of C. parvum in contrast to 25% by mZN staining with a relatively higher prevalence (66·7%) in younger (8-14-day-old) calves. The detection rate of the other enteropathogens associated with C. parvum was 45·71% for C. perfringens followed by Salmonella spp (40·0%), rotavirus (36·0%), coronavirus (16·0%), E. coli (12·0%) and Eimeria spp (4·0%) The sensitivity for detection of C. parvum by ELISA and mZN staining in comparison to PCR was 97·14% and 72·72%, respectively. An important finding of the study was that C. parvum alone was found in only 10% of the diarrhoeic faecal samples, whereas, majority of the samples (90%) showed mixed infections ranging from a combination of two to five agents. This is the first documentary proof of C. parvum and associated pathogens responsible for severe periurban outbreaks of bovine calf diarrhoea culminating in heavy mortality from Northern India.

Morphometric and scanning electron microscopy based identification of Ancylostoma caninum parasites in dog.

Ancylostoma caninum, a blood feeding nematode parasite (Family: Ancylostomatidae, Superfamily: Ancylostomatoidea) can cause anaemia, dark reddish-brown to black haemorrhagic diarrhoea, dehydration, wasting and deaths due to heavy blood loss. Adult hook worm parasites recovered from the intestine of a stray dog at the time of necropsy were identified as A. caninum based on morphological characters and morphometric observations involving scanning electron microscopy (SEM). Different developmental stages of hookworm eggs viz. 8 cell stage, morula, gastrula and vermiform were observed during the culture process of faecal sample. High quality SEM photographs showed teeth of dimensions 52.5, 42.3 and 23.5 µm on one side and 55.4, 43.8 and 21.0 µm on the other side along with the presence of characteristic transverse cuticular striations on body surface of A. caninum parasites.

Validation of Romanowsky staining as a novel screening test for the detection of faecal cryptosporidial oocysts.

Cryptosporidiosis is an emerging waterborne protozoan disease and one of the major causes of neonatal diarrhea in humans and animals. But the disease remains under diagnosed due to lack of availability of special stains in majority of laboratories at primary health centers. Therefore, it requires a rapid screening test for routine diagnosis in conventional laboratory set up. In this pursuit, the present study was planned. During this study, fecal samples from 100 representative animals randomly selected from 17 out breaks of bovine calf diarrhea, were stained with modified Ziehl Neelsen staining (mZN) and Leishman's stain to demonstrate cryptosporidial oocysts and for routine fecal examination, respectively. By mZN staining, 25 cases confirmed the presence of cryptosporidial oocysts. However, examination of Leishman's stained fecal smears revealed round hollow unstained bodies resembling cryptosporidia in 20 cases. Therefore, a comparative morphometric analysis was made between the two techniques to determine their relative efficacy in demonstrating cryptosporidia in the feces of affected animals. The analyses showed that the Leishman's stain can be effective in making a presumptive diagnosis of cryptosporidiosis with a little experience. Confirmation of cryptosporidiosis was done by histopathological examination of intestinal sections of calves died during these out breaks. The findings appear to have great clinical value for routine laboratory screening of fecal samples for cryptosporidiosis as conventional Romanowsky stains are readily available and used for multipurpose examination in most of the laboratories at grass root level. Perusal of literature proved this to be the first attempt at easy diagnostics for cryptosporidiosis.

Postanastomotic transplant renal artery stenosis: association with de novo class II donor-specific antibodies.

In this study, we analyze the outcomes of transplant renal artery stenosis (TRAS), determine the different anatomical positions of TRAS, and establish cardiovascular and immunological risk factors associated with its development. One hundred thirty-seven of 999 (13.7%) patients had TRAS diagnosed by angiography; 119/137 (86.9%) were treated with angioplasty, of which 113/137 (82.5%) were stented. Allograft survival in the TRAS+ intervention, TRAS+ nonintervention and TRAS- groups was 80.4%, 71.3% and 83.1%, respectively. There was no difference in allograft survival between the TRAS+ intervention and TRAS- groups, p = 0.12; there was a difference in allograft survival between the TRAS- and TRAS+ nonintervention groups, p < 0.001, and between the TRAS+ intervention and TRAS+ nonintervention groups, p = 0.037. TRAS developed at the anastomosis, within a bend/kink or distally. Anastomotic TRAS developed in living donor recipients; postanastomotic TRAS (TRAS-P) developed in diabetic and older patients who received grafts from deceased, older donors. Compared with the TRAS- group, patients with TRAS-P were more likely to have had rejection with arteritis, odds ratio (OR): 4.83 (1.47-15.87), p = 0.0095, and capillaritis, OR: 3.03 (1.10-8.36), p = 0.033. Patients with TRAS-P were more likely to have developed de novo class II DSA compared with TRAS- patients hazard ratio: 4.41 (2.0-9.73), p < 0.001. TRAS is a heterogeneous condition with TRAS-P having both alloimmune and traditional cardiovascular risk factors.

A non-destructive scattering technique for investigation of pulmonary edema.

In many biomedical studies, the density of a biological system is of great importance to investigate its structure or functioning. In the present work, for the density measurement of lung phantom, the scattering of 59.54 and 662keV gamma photons are studied using HPGe and NaI(Tl) detectors, respectively. Phantoms simulating lung density are prepared by mixing appropriate amount of saw dust and distilled water. The regression lines, obtained from experimental data of scattered spectra, provide the amount of excessive water storage in lungs, hence the technique has the potential for a measure of pathological state like pulmonary edema. The technique is quite sensitive for small change (∼23Kgm(-3)) in the density of lung phantom. Also, Compton scatter profile measurements (in case of 59.54keV) results that the technique is less sensitive beyond chest wall thickness of ∼26mm due to overlying scatter components in the measured spectrum. A portable non-invasive system described presently may be used for various industrial applications also.

Liver resection for metastatic soft tissue sarcoma: an analysis of prognostic factors.

AIM: The aim of this retrospective study was to analyse the outcome following hepatic resection for metastatic STS and to identify factors predicting survival. METHODS: All patients who underwent hepatic resection for metastatic STS between August 1997 and April 2009 were included. The data was obtained from a prospectively maintained database. Patients' demographics, clinico-pathological parameters, overall survival and the factors predicting survival were analysed. RESULTS: Thirty-six patients underwent hepatic resection for metastasis, with a median age of 58 years. The predominant site of primary tumour was the gastro-intestinal tract (50%). Leiomyosarcoma was the most common histological type (54%). The median interval between the primary and metastatic resections was 17 months. Thirteen patients had synchronous tumours. 24 patients had major liver resections and 10 patients had bi-lobar disease. The median number of liver lesions resected was 1(1-6) and the median maximum diameter was 11 cm (1-26 cm). R0 resection was performed in 31 patients. The 1-, 3- and 5-year overall survival from the time of metastasectomy was 90.3%, 48.0% and 31.8% respectively, with a median survival of 24 months. Factors associated with poor survival on univariate analysis were the presence of high grade tumours (p = 0.04), primary leiomyosarcoma (p = 0.01) and positive resection margin of liver metastasis (p = 0.04), whilst multivariate analysis predicted primary leiomyosarcoma as a risk factor for poor survival (p = 0.01). CONCLUSION: Hepatic resection for metastatic STS appears to be valuable in carefully selected patients with acceptable long-term survival. The aim of surgery must be an R0 resection to offer a chance of cure.

Incoherent scattering of gamma photons for non-destructive tomographic inspection of pipeline.

A scanner system, operating in a non-destructive and non-invasive way, is presented for pipeline to determine its location in land soil, wall thickness, type of liquid flowing and crack/blockage position. The present experiment simulates a real case where pipe corrosion (wall thinning) under insulation can be known from the study of incoherent scattering of 662 keV gamma photons. The incoherent scattered intensity, obtained by unfolding (deconvolution) the experimental pulse-height distribution of NaI(Tl) scintillation detector with the help of inverse response matrix, provides the desired information. The method is quite sensitive for small change (approximately 1 mm) in the thickness of pipe wall, locating a defect of 1mm width under insulation and a small change (approximately 0.1 gm cm(-3)) in the density of liquid flowing through pipe.

Systematic review of the evidence base for the medical treatment of paediatric inflammatory bowel disease.

OBJECTIVE: To systematically review the evidence base for the medical (pharmaceutical and nutritional) treatment of paediatric inflammatory bowel disease. METHODS: Key clinical questions were formulated regarding different treatment modalities used in the treatment of paediatric (not adult-onset) IBD, in particular the induction and maintenance of remission in Crohn disease and ulcerative colitis. Electronic searches were performed from January 1966 to December 2006, using the electronic search strategy of the Cochrane IBD group. Details of papers were entered on a dedicated database, reviewed in abstract form, and disseminated in full for appraisal. Clinical guidelines were appraised using the AGREE instrument and all other relevant papers were appraised using Scottish Intercollegiate Guidelines Network methodology, with evidence levels given to all papers. RESULTS: A total of 6285 papers were identified, of which 1255 involved children; these were entered on the database. After critical appraisal, only 103 publications met our criteria as evidence on medical treatment of paediatric IBD. We identified 3 clinical guidelines, 1 systematic review, and 16 randomised controlled trials; all were of variable quality, with none getting the highest methodological scores. CONCLUSIONS: This is the first comprehensive review of the evidence base for the treatment of paediatric IBD, highlighting the paucity of trials of high methodological quality. As a result, the development of clinical guidelines for managing children and young people with IBD must be consensus based, informed by the best-available evidence from the paediatric literature and high-quality data from the adult IBD literature, together with the clinical expertise and multidisciplinary experience of paediatric IBD experts.

Recurrent abdominal pain in childhood: the functional element.

Many children report chronic abdominal pain that is severe and disruptive to normal lifestyle and schooling. Assessment and management depends on indentifying those with underlying organic disease, such as chronic infection, celiac disease or inflammatory bowel disease, but avoiding unnecessary invasive investigations. In those with a functional gut disorder, the aim of therapy is reassurance, a return to normal activity and symptom control. We address the evidence for the use of investigative and management strategies in situations where recurrent abdominal pain is likely to be a functional disorder. Epidemiological studies of European and American populations show that organic causes are uncommon, and that chronic abdominal pain is a risk factor for functional gut disorders in adulthood. There is a paucity of high quality therapeutic trials, none showing conclusive evidence of benefit. Psychological interventions, such as cognitive behavioral and family therapy are effective, reducing symptoms and improving school attendance. Asian studies suggest gastrointestinal infection, such as giardiasis, are common causes of recurrent abdominal pain, but that functional abdominal pain is also prevalent.

The early stool patterns of young children with autistic spectrum disorder.

AIM: To investigate whether children with autistic spectrum disorder (ASD) have bowel symptoms consistent with underlying enterocolitis. METHODS: Information on children's stool patterns and gut symptoms collected by questionnaire at 4 weeks and at 6, 18, 30 and 42 months of age were available for 12,984 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Data on the 78 children identified by local health and/or education systems to have special educational provision for ASD were compared with the 12,906 remaining children in the cohort. RESULTS: Comparison of the ASD and control group during the first 3.5 years of life showed no major differences in stool colour or consistency, or in frequency of diarrhoea, constipation, bloody stools or abdominal pain. The ASD children had similar stool frequency up to 18 months, but there was a trend for ASD children to pass more stools at 30 months (OR 3.73, 95% CI 1.11 to 12.6; p = 0.004) and at 42 months (OR 6.46, 95% CI 1.83 to 22.7; p<0.001), although only three children passed more than 4 stools/day. Repeating the analysis on only those cases diagnosed as having classical childhood autism resulted in very similar findings. CONCLUSIONS: During the first 42 months of life, ASD children had a stool pattern that was very similar to that of other children, apart from a slight increase in stool frequency at 30 and 42 months. There were no symptoms to support the hypothesis that ASD children had enterocolitis.

The variation in stool patterns from 1 to 42 months: a population-based observational study.

OBJECTIVE: To document the normal stool patterns of young children. DESIGN: Prospective population-based longitudinal study. SETTING: Avon Longitudinal Study of Parents and Children (ALSPAC). SUBJECTS: 12,984 children, whose parents completed questionnaires at 4 weeks, 6, 18, 30 and 42 months on their frequency of bowel movements and the consistency and colour of their stools. RESULTS: Stool frequency declined from a mean of 3.0 times/day (3rd centile 0.6, 97th centile 5.9) at 4 weeks to 1.3 times/day (0.6, 2.7) at 42 months. Stool consistency was soft in most babies with nearly half passing liquid or curdy stool at 4 weeks. 14% of babies usually passed a hard stool at 4 weeks, rising to 30% at 42 months. Stool colour was commonly yellow at 4 weeks and had changed to brown by 6 months. Black stools were extremely unusual at all ages. CONCLUSIONS: These data on the changes with age in the stool patterns of young children will be useful for clinicians.

Rabies in South Asia: epidemiological investigations and clinical perspective.

A five year study (1995-1999) was conducted in Northern India to investigate epidemiological aspects of rabies in domestic animals. For this purpose, brain tissue samples were collected from rabies suspect animals including 231 dogs, 79 buffaloes, 46 cattle and 28 wild species. Out of the 384 rabies suspected cases, 56% were positive for rabies by fluorescent antibody test (FAT), the mouse inoculation test (MIT) and histopathological techniques. Variations in clinical signs of rabies were recorded for individual animals with significant differences observed between dogs and bovines with respect to hypersalivation, paralysis, recognition of owners and aggression. Likewise, differences in the clinical course of disease between cows and buffaloes regarding hypersalivation and micturition were observed. Rabies incidence was highest among adult male dogs and indicated a seasonal pattern with more rabies cases during certain months of the year (January to April, and August to November). Its impact on cow/buffalo rabies is discussed. Accumulated history records revealed that 78% of owned rabid dogs were not prophylactically vaccinated against rabies.