Search PubMed⌕ Search

Biomedical subjects

M Singh

Publications and source records attributed to M Singh.

At least 37 records · Page 2Linked to original sources

Estimation of serum zinc and copper in children with acute diarrhea.

Diarrhea is, in reality, as much a nutritional disease as one of fluid and electrolyte loss. Children who die from diarrhea, despite good management of dehydration, are usually malnourished and often severely so. In this study, we determined the serum levels of zinc and copper before and after standard oral rehydration solution (ORS) therapy in children with acute diarrhea and correlated it with diarrheal duration and severity. One hundred ten children suffering from acute diarrhea were included. Serum zinc and copper levels of these children were estimated at the time of enrollment and after treatment with standard ORS therapy. This study shows that children suffering from acute diarrhea show a statistically significant decrease of 13.1% and 12.8% in serum zinc and copper concentrations, respectively, compared to normal. These levels further decrease by 22.6% and 22.4%, respectively, after treatment with standard ORS therapy. Our study shows that children with the lower plasma zinc and copper levels suffered with more severe and longer duration of diarrhea. Zinc and copper supplementation could be added to standard ORS therapy for the reduction in morbidity and mortality associated with acute diarrhea in children.

Acute Disease↗

Simple and economical method for speciation and resistotyping of clinically significant coagulase negative staphylococci.

An attempt was made to speciate 102 clinically significant isolates of coagulase negative staphylococci (CoNS) by a practical scheme adapted from various references. This scheme utilizes slide and tube coagulase test, urease test ornithine decarboxylase, novobiocin susceptibility and aerobic acid from mannose for assigning species group. Inclusion of one or two additional tests in a species group could identify the isolates to species level. Ninety eight (97%) isolates were conveniently identified as S. epidermidis (41%), S. saprophyticus (16.6%), S. haemolyticus (14.7%), S. hominis (14.7%), S. lugdunensis (4.9%), S. schleiferi (1.9%) and S. capitis (1.9%). Only four isolates were not identified to the species level, two of which were probably S. capitis subspecies ureolyticus / S. warneri / S. simulans . Antibiotic susceptibility testing showed maximum resistance to ampicillin (89%) followed by cefotaxime (59%) with no resistance to vancomycin. The increasing recognition of pathogenic potential of CoNS and emergence of drug resistance amongst them denotes the need to adopt simple laboratory procedures to identify and understand the diversity of staphylococci isolated from clinical material.

Bacteriological Techniques↗

Cathepsin L cysteine proteinase in the diagnosis of bovine Fasciola gigantica infection.

Cathepsin L cysteine proteinase from Fasciola gigantica was evaluated for its potential in the early prepatent detection of this helminth infection in bovine calves. Five cross-bred bovine calves were experimentally infected with 400 metacercariae/calf and evaluated for anti-cathepsin L antibody response. F. gigantica infection in these calves could be detected 4 weeks post-infection using an ELISA, dipstick ELISA and Western blotting with 100% sensitivity. The antigen was also used to detect F. gigantica field infection in cattle, by screening 256 sera of these animals by an ELISA, which demonstrated an overall infection rate of 26.95%. Preliminary studies showed that F. gigantica cathepsin L cysteine proteinase does not cross-react with Paramphistomum epiclitum, Gigantocotyle explanatum and hydatid cyst antigens. However, extensive studies on the cross-reactivity of this antigen with related helminth parasites of cattle and buffaloes are required, before this antigen can be considered suitable for immuno-diagnosis of fasciolosis in these ruminants.

Animals↗

Prevalence and incidence of gastroduodenal ulcers during treatment with vascular protective doses of aspirin.

BACKGROUND: Aspirin is valuable for preventing vascular events, but information about ulcer frequency is necessary to inform risk-benefit decisions in individual patients. AIM: To determine ulcer prevalence and incidence in a population representative of those given aspirin therapy and evaluate risk predictors. METHODS: Patients taking aspirin 75-325 mg daily were recruited from four countries. Exclusions included use of gastroprotectant drugs or other non-steroidal anti-inflammatory drugs. We measured point prevalence of endoscopic ulcers, after quantitating dyspeptic symptoms. Incidence was assessed 3 months later in those eligible to continue (no baseline ulcer or reason for gastroprotectants). RESULTS: In 187 patients, ulcer prevalence was 11% [95% confidence interval (CI) 6.3-15.1%]. Only 20% had dyspeptic symptoms, not significantly different from patients without ulcer. Ulcer incidence in 113 patients followed for 3 months was 7% (95% CI 2.4-11.8%). Helicobacter pylori infection increased the risk of a duodenal ulcer [odds ratio (OR) 18.5, 95% CI 2.3-149.4], as did age >70 for ulcers in stomach and duodenum combined (OR 3.3, 95% CI 1.3-8.7). CONCLUSIONS: Gastroduodenal ulcers are found in one in 10 patients taking low-dose aspirin, and most are asymptomatic; this needs considering when discussing risks/benefits with patients. Risk factors include older age and H. pylori (for duodenal ulcer).

Aged↗

Effect of methyl substitution of benzene on the percutaneous absorption and skin irritation in hairless rats.

The permeation rate and skin retention of benzene and methylbenzenes were assessed in vitro using hairless rat skin. The effects of unocclusive dermal exposures of these chemicals (15 microl every 2h for 8h a day for 4 days) on the transepidermal water loss (TEWL), erythema and skin histopathology were measured in CD hairless rats. The expression of IL-1 alpha and TNF-alpha in the skin and blood were measured at the end of dermal exposures. The flux of benzene was about 1.5-, 2.5- and 80-fold higher than toluene, xylene and tetramethyl benzene isomers (TMB), respectively, and the values were inversely correlated with molecular weight (r(2)=0.7455) and logoctanol-water partition coefficient (r(2)=0.7831). The retention of chemicals in stratum corneum (SC) was in the order of TMB>xylene>toluene approximately benzene. The TEWL and erythema data demonstrated that the irritation was in the following order: TMB>xylene>benzene. The histo-pathological examination showed that xylene and TMB induced granulocyte infiltration, swelling of the epidermis, and extensive disruption and damage of stratum corneum. Likewise, the expression of IL-1 alpha in the blood and TNF-alpha in the skin after dermal exposures was higher for TMB followed by xylene and benzene compared to control. In conclusion, the aromatic hydrocarbon chemicals induced cumulative irritation upon low-level repeat exposures for a 4-day period and the irritation increased with the number of methyl groups of benzene. The affinity of the chemical to SC and their gradual accumulation in the skin in the present study is the reason for the differences in the skin irritation profiles of different aromatic chemicals. Our ultimate goal is to develop a biologically based model that connects skin retention of chemical to the skin irritation response. The findings of the present study will be helpful in understanding the role of these chemicals in the jet fuel and various petroleum based fuels in inducing skin irritation response.

Animals↗

The effect of occlusive and unocclusive exposure to xylene and benzene on skin irritation and molecular responses in hairless rats.

Aromatic hydrocarbons readily penetrate the skin on dermal exposure, leading to irritation, inflammation and cytotoxicity. The effects of short-term occlusive and long-term unocclusive dermal exposure to benzene and xylene on the skin irritation response (transepidermal water loss (TEWL), skin moisture content and erythema) and cytokine/chemokine expression (interleukin-1alpha (IL-1alpha), tumor necrosis factor-alpha (TNF-alpha) and monocyte chemoattractant protein-1 (MCP-1)) were investigated in hairless rats. Occlusive dermal exposure was carried out with 230 microL of the chemicals for 1 h using Hill top chambers. In unocclusive dermal exposure, 15 microL of the chemicals were applied to the skin every 2 h, for 8 h a day, for 4 days. The occlusive dermal exposure revealed a clear difference in the TEWL and erythema response of these chemicals (xylene>benzene) whereas unocclusive exposure revealed similar TEWL and erythema scores for both benzene and xylene. The expression of IL-1alpha was elevated 2.5- and 3.8-fold in response to occlusive and unocclusive exposure, respectively, vs control (P<0.01) for both the chemicals (benzene and xylene). Similarly, TNF-alpha levels were elevated about 2.4- and 6.0-fold as a result of occlusive and unocclusive exposure, respectively, vs control (P<0.01). These results show that unocclusive exposure induced significantly higher TNF-alpha expression than occlusive exposure (P<0.05). The MCP-1 expression in blood was slightly elevated compared with the control group, but this increase was not statistically significant (P>0.05). Similarly, MCP levels in skin were increased approximately 1.7- and 1.8-fold by occlusive and unocclusive exposure, respectively, compared with the control group (P<0.05). Our study demonstrates that the skin irritation profiles of benzene and xylene are similar and unocclusive long-term exposure to small amounts of these chemicals can induce more skin irritation and cytokine response than occlusive exposure.

Administration, Cutaneous↗

Robust pulmonary nodule segmentation in CT: improving performance for juxtapleural cases.

Two novel methods are proposed for robust segmentation of pulmonary nodules in CT images. The proposed solutions locate and segment a nodule in a semi-automatic fashion with a marker indicating the target. The solutions are motivated for handling the difficulty to segment juxtapleural, or wall-attached, nodules by using only local information without a global lung segmentation. They are realized as extensions of the recently proposed robust Gaussian fitting approach. Algorithms based on i) 3D morphological opening with anisotropic structuring element and ii) extended mean shift with a Gaussian repelling prior are presented. They are empirically compared against the robust Gaussian fitting solution by using a large clinical high-resolution CT dataset. The results show 8% increase, resulting in 95% correct segmentation rate for the dataset.

Algorithms↗

Non-invasive imaging and characterisation of human foot by multi-probe laser reflectometry and Monte Carlo simulation.

Diffusely backscattered signals from the human foot sole tissues of normal subjects (n = 5) were obtained by multiprobe laser reflectometry. The colour-coded images were constructed from data on the variation of normalised backscattered intensity (NBI), after interpolation and median filtering. The maximum and minimum NBI values at the arch and heel regions of the foot sole, respectively, were observed. The mean NBI at the arch region was significantly higher compared with that at other regions (p < 0.0001). The images of optical parameters of normal tissues show point-to-point variation, attributed to their compositional changes. The pattern of variation of the NBI of a diabetic subject (glucose level 170 mg dl(-1)) was associated with highly significant variation at the lateral sides of the fore- and middle-foot compared with that of normal subjects.

Adult↗

Estrogens, progestins, menopause and neurodegeneration: basic and clinical studies.

Two classes of ovarian steroids, estrogens and progestins, are potent in protecting neurons against acute toxic events as well as chronic neurodegeneration. Herein we review the evidence for neuroprotection by both classes of steroids, provide plausible mechanisms for these potent neuroprotective activities and indicate the need for further clinical trials of both estrogens and progestins in protection against acute and chronic conditions that cause neuronal death. Estrogens at concentrations ranging from physiological to pharmacological are neuroprotective in a variety of in vitro and in vivo models of cerebral ischemia and brain trauma as well as in reducing key neuropathologies of Alzheimer's disease. While the mechanisms of this potent neuroprotection are currently unresolved, a mitochondrial mechanism is involved. Progestins have been recently shown to activate many of the signaling pathways used by estrogens to neuroprotect, and progestins have been shown to protect against neuronal loss in vitro and in vivo in a variety of models of acute insult. Collectively, results of these animal and tissue culture models suggest that the loss of both estrogens and progestins at the menopause makes the brain more vulnerable to acute insults and chronic neurodegenerative diseases. Further clinical assessment of appropriate regimens of estrogens, progestins and their combination are supported by these data.

Animals↗

Formulation and evaluation of aerosolized celecoxib for the treatment of lung cancer.

PURPOSE: We examined the effect of aerosolized celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on the in vitro cytotoxicity and apoptotic response of docetaxel against the human lung carcinoma cell lines A549 and H460. METHODS: A metered dose inhaler (MDI) formulation of celecoxib was prepared and evaluated for its medication delivery and aerodynamic properties. The in vitro cytotoxicity of the aerosolized celecoxib-MDI alone or in combination with docetaxel was assessed using a six-stage viable impactor by a previously established method. The induction of apoptosis was evaluated by morphologic examination (acridine orange and Hoechst staining) and DNA fragmentation. Furthermore, in an attempt to identify molecular targets involved in the anticancer mechanisms of celecoxib and docetaxel, we examined their effect on the expression of an array of markers involved in the COX-2 dependent and independent pathways. RESULTS: The celecoxib-MDI had a medication delivery of 231.3 microg/shot, mass median aerodynamic diameter (MMAD) of 1.4 microm (GSD = 1.9), and respirable fraction of 50.7%. The celecoxib-MDI (2 shots) in combination with docetaxel had cell kills as high as 81.3% and 67.7% in A549 and H460 cells, respectively. Hoechst and acridine orange staining showed an enhanced induction of apoptosis in A549 and H460 cells exposed to aerosolized celecoxib with docetaxel, which was further confirmed by DNA fragmentation. Western blot analysis showed a significant reduction in cPLA2 expression in both A549 and H460 cells treated with the combination of celecoxib with docetaxel. In the COX-2 independent pathway, there was a significant increase in the expression of PPAR-gamma and p53, whereas pro-caspase-3 expression was significantly decreased, which may contribute to the enhanced apoptotic response observed with the combination treatment. CONCLUSIONS: Our results suggest that aerosolized celecoxib significantly enhances the in vitro cytotoxicity and apoptotic response of docetaxel against A549 and H460 cells, and this enhanced activity is mediated via alterations in expression of various molecular targets involved in apoptosis.

Aerosols↗

Spontaneous common bile duct rupture in pregnancy.

This report describes how a rare condition in pregnancy can present with features resembling more common diagnoses in the unwell obstetric patient. Our patient presented in late pregnancy initially with clinical features similar to mild preeclampsia, with proteinuric hypertension, epigastric pain and mildly deranged liver function tests. She went on to develop signs of acute abdomen associated with a persistent tachycardia and hypotension; there was evidence of fetal compromise. Following resuscitation, emergency caesarean section was performed and evolved into a laparotomy. The diagnosis was not clear clinically at this stage, but a retrospective amylase sample suggested acute pancreatitis. There was no clinical evidence of biliary perforation, but ongoing clinical suspicion prompted a CT of the abdomen. This proved unhelpful and our diagnostic dilemma was only resolved by endoscopic retrograde cholangiopancreatography, which demonstrated a biliary leak. A stent was placed with subsequent improvement in the patient's condition. With anaesthetists increasingly involved in the multi-disciplinary management of acutely sick obstetric patients, our case highlights the need for every practitioner involved in such cases to assess each individual fully, and be constantly aware that the diagnosis might not be obvious.

Adult↗

Inflammatory cerebrospinal fluid analysis in cats: clinical diagnosis and outcome.

The medical records of 62 cats with clinical signs of central nervous system disease and accompanying inflammatory cerebrospinal fluid (CSF) analysis were examined retrospectively to determine if signalment, clinical signs, CSF analysis and ancillary testing could accurately predict the type of central nervous system disease that was present. An inflammatory CSF was defined as one in which a total nucleated cell count was greater than 5 cells/microl or one in which the total nucleated cell count was normal but the nucleated cell differential count was abnormal. Sex, degree of CSF inflammation, neuroanatomical location and systemic signs provided little contributory information to the final diagnosis. In 63% of the cases a presumptive diagnosis could be made based on a combination of clinical signs, clinicopathological data and ancillary diagnostic tests. CSF analysis alone was useful only in the diagnosis of cats with feline infectious peritonitis, Cryptococcus species infection, lymphoma and trauma. Overall, despite extensive diagnostic evaluation, a specific diagnosis could not be made in 37% of cats. The prognosis for cats with inflammatory CSF was poor with 77% of cats surviving less than 1 year.

Animals↗

Role of collectins in innate immunity against aspergillosis.

The protective role of lung surfactant proteins SP-A, SP-D and MBL in the host defense against both allergic and invasive aspergillosis was identified and established by a series of in vitro and in vivo studies. Therapeutic administration of SP-D and MBL proteins in a murine model of pulmonary invasive aspergillosis rescued mice from death. In mice mimicking human allergic bronchopulmonary aspergillosis, SP-A and SP-D suppressed IgE levels, eosinophilia, pulmonary cellular infiltration and cause a marked shift from a pathogenic Th2 to a protective Th1 cytokine profile. SP-A and SP-D knock-out mice studies made significant contributions in understanding the mechanisms by which SP-A and SP-D modulate the host defense response in patients suffering from pulmonary allergies and infections. The results suggested that individuals with any structural or functional defects in these innate immune molecules due to genetic variations might be susceptible to aspergillosis. SNPs in SP-A2 and MBL genes showed significant associations with patients of allergic bronchopulmonary aspergillosis in an Indian population. The patients carrying either one or both of GCT and AGG alleles of SP-A2 and patients with A allele at position 1011 of MBL had markedly higher eosinophilia, total IgE antibodies and lower FEV1 (the clinical markers of ABPA). Our results show that collectins play an important role in Aspergillus mediated allergies and infections.

Animals↗