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M Sharma

Publications and source records attributed to M Sharma.

At least 37 records · Page 2Linked to original sources

Coordinated expression and immunogenicity of an outer membrane protein from Salmonella enterica serovar Typhi under iron limitation, oxidative stress and anaerobic conditions.

Successful pathogens overcome the environmental stresses by the coordinated expression of various genes and eventually proteins. Since, the surface of the microbe is likely to come in contact with the host initially, an attempt was made to identify the outer membrane proteins (OMPs), if any, which may get expressed under more than one environmental conditions simulating the in vivo ones. In the present study, Salmonella enterica serovar Typhi was grown under iron-limited, oxidative stress as well as anaerobic conditions and the OMP profiles were compared. A 69 kDa OMP was found to express with enhanced intensity under the selected stress conditions in comparison to normal conditions. The phenotypic similarity among the proteins was assessed on the basis of their molecular weight, cross reactivity and HPLC. The protein expressed under oxidative stress and anaerobic conditions reacted with the antibodies raised against iron-regulated outer membrane protein (IROMP), indicating the sharing of at least some of the epitopes. A single peak observed after subjecting the pooled 69 kDa protein sample and appearance of a single band on SDS-PAGE thereafter, confirmed the purity and phenotypic similarity of the 69 kDa OMP. Reactivity of pooled 69 kDa protein with 85% of sera from typhoid patients revealed the in vivo expression of this protein. The results of this study indicate the coordination of this phenotype under iron stress, oxidative stress and anaerobic conditions. In view of the expression of the 69 kDa protein under the selected stress conditions and their in vivo immunogenicity, these findings may be relevant for the better understanding of the host-microbe interactions and for the further development of diagnostic and preventive strategies.

Animals↗

Interdigitating dendritic cell sarcoma of the parotid gland.

Interdigitating dendritic cell sarcomas (IDCSs) are extremely uncommon tumours that arise predominantly in lymphoid tissue. We report a case of an IDCS arising in the parotid gland of a 73-year-old man. Clinically, a primary salivary gland tumour was suspected but fine needle aspiration cytology suggested a soft tissue tumour. A diagnosis of IDCS was made on histopathological examination of the resection specimen, with subsequent confirmation by electron microscopy. Given the extreme rarity of this tumour at this site, it is unlikely to be a common diagnostic problem, but the importance of multiple diagnostic modalities is emphasized. The findings of cytology, histology, immunohistochemistry and electron microscopy have not previously been described together in a single case report of this tumour.

Aged↗

Prawns masquerading as endobronchial tumours.

This report details the events surrounding the case of an 89-year-old woman referred for surgery with a suspected endobronchial tumour. At rigid bronchoscopy she was found to have inspissated sputum within which the remains of organic foreign bodies (king prawns) were found obstructing the left main and left upper lobe bronchi. We outline her presentation, initial diagnosis and eventual outcome, and re-emphasise the importance of bronchoscopy as a vital tool in the assessment of any endoluminal lesion of the airway.

Aged, 80 and over↗

The fragile X tremor ataxia syndrome in the differential diagnosis of multiple system atrophy: data from the EMSA Study Group.

The recent identification of fragile X-associated tremor ataxia syndrome (FXTAS) associated with premutations in the FMR1 gene and the possibility of clinical overlap with multiple system atrophy (MSA) has raised important questions, such as whether genetic testing for FXTAS should be performed routinely in MSA and whether positive cases might affect the specificity of current MSA diagnostic criteria. We genotyped 507 patients with clinically diagnosed or pathologically proven MSA for FMR1 repeat length. Among the 426 clinically diagnosed cases, we identified four patients carrying FMR1 premutations (0.94%). Within the subgroup of patients with probable MSA-C, three of 76 patients (3.95%) carried premutations. We identified no premutation carriers among 81 patients with pathologically proven MSA and only one carrier among 622 controls (0.16%). Our results suggest that, with proper application of current diagnostic criteria, FXTAS is very unlikely to be confused with MSA. However, slowly progressive disease or predominant tremor are useful red flags and should prompt the consideration of FXTAS. On the basis of our data, the EMSA Study Group does not recommend routine FMR1 genotyping in typical MSA patients.

Aged↗

The prognostic significance of micrometastases in node-negative squamous cell carcinoma of the vulva.

Nodal involvement is one of the most significant prognostic factors in squamous cell carcinoma (SCC) of the vulva. We conducted a retrospective analysis of 31 women with histologically node-negative SCC from a population-based cohort of Grampian women. Median follow-up was 42 months after radical vulvectomy with groin node dissection. In total, 13 women (42%) were found to have micrometastases on immunohistochemistry. The risk of recurrence was almost 20-fold higher in those with micrometastases compared to those without (hazard ratio=19.6 (95% CI 2.3-171).

Adult↗

Ultra-wide bore 900 MHz high-resolution NMR at the National High Magnetic Field Laboratory.

Access to an ultra-wide bore (105 mm) 21.1 T magnet makes possible numerous advances in NMR spectroscopy and MR imaging, as well as novel applications. This magnet was developed, designed, manufactured and tested at the National High Magnetic Field Laboratory and on July 21, 2004 it was energized to 21.1 T. Commercial and unique homebuilt probes, along with a standard commercial NMR console have been installed and tested with many science applications to develop this spectrometer as a user facility. Solution NMR of membrane proteins with enhanced resolution, new pulse sequences for solid state NMR taking advantage of narrowed proton linewidths, and enhanced spatial resolution and contrast leading to improved animal imaging have been documented. In addition, it is demonstrated that spectroscopy of single site (17)O labeled macromolecules in a hydrated lipid bilayer environment can be recorded in a remarkably short period of time. (17)O spectra of aligned samples show the potential for using this data for orientational restraints and for characterizing unique details of cation binding properties to ion channels. The success of this NHMFL magnet illustrates the potential for using a similar magnet design as an outsert for high temperature superconducting insert coils to achieve an NMR magnet with a field >25 T.

Image Enhancement↗

Enhanced pro-inflammatory chemokine/cytokine response triggered by pathogenic Entamoeba histolytica : basis of invasive disease.

The virulence of Entamoeba histolytica is governed by adhesion/colonization in the gut which is mediated by a galactose specific lectin. Two morphologically identical but distinct species i.e. pathogenic E. histolytica and non-pathogenic E. dispar, can be differentiated by distinct epitopes in the lectin. Both species bind to colonic epithelial cells, but only E. histolytica infection induces an inflammatory response and subsequent pathogenesis. Thus, comparing the responses of the intestinal cells to pathogenic and non-pathogenic lectins is a point of interest. The pathogenic lectin causes cytolysis of epithelial and immune-competent cells. Our data (both qualitative and mRNA quantitation) indicate that the epithelial cells responded to E. histolytica lectin with an increased expression of pro-inflammatory IL-2, IL-6, IL-8, MIP-1alpha, MCP-1, RANTES, GROalpha and GMCSF as compared to E. dispar lectin. The pathogenic LCM induced a significant increase in intracellular calcium concentration, proliferative response and chemotaxis of lymphocytes from ALA patients as compared to non-pathogenic LCM. High RANTES and IL-6 were induced in patients' lymphocytes by pathogenic LCM, along with their receptors CCR5 and CD126 as compared to NP-LCM. The local release of such a complex network of cytokines/chemokines could explain the histopathology of E. histolytica infection. The comparative low levels of these chemokines/pro-inflammatory cytokines and high levels of anti-inflammatory IL-10 in response to non-pathogenic E. dispar could explain the absence of an acute inflammatory response and the disease process. The cytokines and chemokines may provide a mechanism for initiation, amplification or containment of inflammation during disease state.

Agglutination Tests↗

One stop fertility clinic.

UNLABELLED: The objective of this study was to determine the feasibility and acceptability of out-patient based investigation of infertile couples using a prospective observational study based in a large undergraduate teaching hospital. We studied couples referred to secondary care for investigation of their infertility. Investigations involved pelvic ultrasound, diagnostic hysteroscopy and culdoscopy. The main outcome measures were feasibility of investigations, findings, patient views, and a management plan. RESULTS: 199 of 347 (57.3%) couples referred met our selection criteria, and 162 of this group have attended. Thirty-one (19.1%) were judged to be unsuitable for culdoscopy, and culdoscopy failed in a further 29 (17.9%). The average time for the three procedures was 41.2 (SD 17.2) minutes, and over 1/3 of patients were found to have pelvic pathology. The investigations were well tolerated and there was only one complication necessitating admission to hospital. Most patients appreciated the need for a single hospital visit and the availability of immediate results. CONCLUSIONS: A One Stop approach to the investigation of infertility is attractive but not suitable for or desired by all infertile couples. Organisational issues were also identified.

Adult↗

Inactivation of Escherichia coli O157:H7 in biofilm on stainless steel by treatment with an alkaline cleaner and a bacteriophage.

AIMS: To determine the effectiveness of an alkaline cleaner used in food-processing plants and a lytic bacteriophage specific for Escherichia coli O157:H7 in killing wild type and rpoS-deficient cells of the pathogen in a biofilm. METHODS AND RESULTS: Wild type and rpoS-deficient cells were attached to stainless steel coupons (c. 7-8 log CFU per coupon) on which biofilms were developed during incubation at 22 degrees C for 96 h in M9 minimal salts media (MSM) with one transfer to fresh medium. Coupons were treated with 100 and 25% working concentrations of a commercial alkaline cleaner (pH 11.9, with 100 microg ml(-1) free chlorine) used in the food industry, chlorine solutions (50 and 100 microg ml(-1) free chlorine), or sterile deionized water (control) at 4 degrees C for 1 and 3 min. Treatment with 100% alkaline cleaners reduced populations by 5-6 log CFU per coupon, a significant (P < or = 0.05) reduction compared with treatment with water. Initial populations (2.6 log CFU per coupon) of attached cells of both strains were reduced by 1.2 log CFU per coupon when treated with bacteriophage KH1 (7.7 log PFU ml(-1)) for up to 4 days at 4 degrees C. Biofilms containing low populations (2.7-2.8 log CFU per coupon) of wild type and rpoS-deficient cells that had developed for 24 h at 22 degrees C were not decreased by more than 1 log CFU per coupon when treated with KH1 (7.5 log PFU ml(-1)) at 4 degrees C. CONCLUSIONS: Higher numbers of cells of E. coli O157:H7 in biofilms are killed by treatment with an alkaline cleaner than with hypochlorite alone, possibly through a synergistic mechanism of alkaline pH and hypochlorite. Populations of cells attached on coupons were reduced by treating with bacteriophage but cells enmeshed in biofilms were protected. SIGNIFICANCE AND IMPACT OF THE STUDY: The alkaline pH, in combination with hypochlorite, in a commercial cleaner is responsible for killing E. coli O157:H7 in biofilms. Treatment with bacteriophage KH1 reduces populations of cells attached to coupon surfaces but not cells in biofilms.

Alkalies↗

Reducing blood loss at open myomectomy using triple tourniquets: a randomised controlled trial.

OBJECTIVES: To evaluate triple tourniquets in controlled conditions and for the first time to investigate the hypothesis that leaving a semi-permanent tourniquet around the uterine artery reduces post-operative bleeding from the uterine incisions. DESIGN: A randomised controlled trial. SETTING: Two University teaching hospitals. POPULATION: Twenty-eight patients with symptomatic fibroids and uterine sizes ranging from 14 to 24 weeks of gestation undergoing open myomectomy. METHODS: A number 1 polyglactin suture was tied around the cervix to occlude the uterine arteries, and polythene tourniquets were tied around the infundibulopelvic ligament to obstruct the ovarian vessels. At the end of the procedure, the ovarian ties were released but the uterine artery suture remained in situ. MAIN OUTCOME MEASURES: Intra-operative blood loss, post-operative blood loss, blood transfusion rates, operative morbidity, uterine blood flow and ovarian function. RESULTS: There was significantly less blood lost in the tourniquet group than in the control group (difference between means 1870 mL, 95% CI 1159-2580 mL, P < 0.0001; transfusion rates of 7% and 79%, P= 0.0003). The volume in the pelvic drain 20 min post-operatively and after 48 hours failed to reach statistical significance between the two groups (P= 0.10 and P= 0.165). There were no differences in uterine artery Doppler resistance indices at five days (P= 0.54), six weeks (P= 0.47), three months (P= 0.49) and at six months (P= 0.18). Day two serum FSH concentrations after surgery were unchanged (P= 0.45), compared with baseline values. CONCLUSIONS: Triple tourniquets are effective in reducing bleeding and transfusion rates. There appears no obvious adverse effect on uterine perfusion or ovarian function.

Adult↗

Outpatient hysteroscopy: traditional versus the 'no-touch' technique.

OBJECTIVE: To assess whether outpatient hysteroscopy using the 'no-touch' technique confers any advantages in terms of patient discomfort over the traditional technique. DESIGN: Prospective randomised controlled study. SETTING: Outpatient hysteroscopy clinic in a large university undergraduate teaching hospital. POPULATION: All women referred for outpatient hysteroscopy in a 12-month period. INTERVENTIONS: Women were randomised to undergo either traditional saline hysteroscopy requiring the use of a speculum and tenaculum, or a 'no-touch' vaginoscopic hysteroscopy which does not require a speculum or tenaculum. Each group was further subdivided to have hysteroscopy with either a 2.9-mm or 4-mm hysteroscope. Patients were asked to complete pre- and postprocedure questionnaires ranking pain scores. MAIN OUTCOME MEASURES: The relative success of each of these techniques, requirement for local anaesthetic and pain scores at different times during the hysteroscopy were recorded at the end of the procedure. The time taken to carry out each procedure was also measured. RESULTS: One hundred and twenty women were recruited in this study: 60 were randomised to traditional hysteroscopy and 60 to 'no-touch' hysteroscopy. The overall success rate for hysteroscopy was 99%. There was no significant difference in the requirement for local anaesthetic between the two groups, but those who underwent 'no-touch' hysteroscopy with a 2.9-mm hysteroscope had the lowest requirement of local anaesthetic (10% compared with 27% in the no-touch hysteroscopy with a 4-mm hysteroscope group). The time taken to perform hysteroscopy and biopsy was significantly shorter with 'no-touch' hysteroscopy (5.9 vs 7.8 min; difference 1.9, 95% CI 0.7-3.1). There were no differences in pain scores between the groups at different times during hysteroscopy. CONCLUSIONS: 'No-touch' or vaginoscopic hysteroscopy is significantly faster to perform than the traditional technique. Although there was no difference in pain scores between the two techniques, local anaesthetic requirements were least in those who underwent 'no-touch' hysteroscopy with a narrow bore hysteroscope.

Adult↗

Thermal tolerance of acid-adapted and unadapted Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in cantaloupe juice and watermelon juice.

AIMS: A study was performed to determine D values of acid-adapted and unadapted cells of Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in cantaloupe juice and watermelon juice. METHODS AND RESULTS: Salmonella enterica serotype Poona, S. enterica serotype Saphra, two strains of E. coli O157:H7, and two strains of L. monocytogenes were grown in tryptic soy broth (TSB) and TSB supplemented with 1% glucose for 24 h at 37 degrees C. Decimal reduction times (D values) of cells suspended in unpasteurized cantaloupe juice and watermelon juice were determined. Acid-adapted cells of Salmonella and E. coli O157:H7, but not L. monocytogenes, had increased thermal tolerance compared with cells that were not acid-adapted. There was no correlation between soluble solids content of the two types of juice and thermal resistance. CONCLUSIONS: Growth of Salmonella and E. coli O157:H7 in cantaloupe juice, watermelon juice, or other acidic milieu, either in preharvest or postharvest environments, may result in cross protection to heat. The pasteurization conditions necessary to achieve elimination of pathogens from these juices would consequently have to be more severe if cells are habituated to acidic environments. SIGNIFICANCE AND IMPACT OF THE STUDY: Insights from this study provide guidance to developing pasteurization processes to eliminate Salmonella, E. coli O157:H7, and L. monocytogenes in cantaloupe juice and watermelon juice.

Adaptation, Physiological↗

Preemptive plasmapheresis and recurrence of FSGS in high-risk renal transplant recipients.

Recurrent focal segmental glomerulosclerosis (FSGS) following transplantation is ascribed to the presence of a circulating FSGS permeability factor (FSPF). Plasmapheresis (PP) can induce remission of proteinuria in recurrent FSGS. This study addressed the efficacy of pre-transplant PP in decreasing the incidence of recurrence in high-risk patients. Ten patients at high-risk for FSGS recurrence because of rapid progression to renal failure (n = 4) or prior transplant recurrence of FSGS (n = 6) underwent a course of 8 PP treatments in the peri-operative period. Recurrences were identified by proteinuria >3 g/day and confirmed by biopsy. Seven patients, including all 4 with first grafts and 3 of 6 with prior recurrence, were free of recurrence at follow-up (238-1258 days). Final serum creatinine in 8 patients with functioning kidneys averaged 1.53 mg/dL. FSGS recurred within 3 months in 3 patients, each of whom had lost prior transplants to recurrent FSGS. Two of these progressed to end-stage renal disease (ESRD) and the third has significant renal dysfunction. Based on inclusion criteria, recurrence rates of 60% were expected if no treatment was given. Therefore, PP may decrease the incidence of recurrent FSGS in high-risk patients. Definitive conclusions regarding optimal management can only be drawn from larger, randomized, controlled studies.

Adult↗

Tumoral calcinosis of the filum terminale.

OBJECTIVE AND IMPORTANCE: Tumoral calcinosis is a rare disorder presenting with tumor-like masses of calcification, usually in soft tissues around large joints. Although this condition has been reported in the spine, this is the first reported instance of this uncommon lesion occurring in the intradural compartment, involving the filum terminale. CLINICAL PRESENTATION: A 55-year-old man presented with back and right leg pain. Initial investigations revealed no cause. A review of his original magnetic resonance imaging scans revealed an intradural calcified mass at L3 level. Surgical exploration was undertaken. INTERVENTION: A L3 laminectomy revealed a calcified mass adherent to the filum terminale. Frozen section from this mass revealed tumoral calcinosis involving the filum terminale. CONCLUSION: This is the first known case of intradural involvement by tumoral calcinosis. This is an uncommon disorder, and a high index of suspicion is required to diagnose the condition, which can recur if incompletely removed.

Calcinosis↗

Effects of Fusarium moniliforme culture material containing known levels of fumonisin B1 on progress of Salmonella Gallinarum infection in Japanese quail: clinical signs and hematologic studies.

To study the individual and combined effects of fumonisin B1 (FB1) toxicity and Salmonella serotype Gallinarum infection, Japanese quail (Coturnix coturnix japonica) were fed Fusarium moniliforme culture material (2.5%), 150 mg FB1/kg ration, and were subsequently challenged orally with Salmonella Gallinarum organisms (2 x 10(4) colony-forming units) at 21 days of age. The chicks were fed culture material containing FB1 from day 5 till the end of the experiment. After being infected with Salmonella Gallinarum, observations were made 1, 2, 3, 5, 7, 10, 14, and 21 days postinfection. The clinical signs of diarrhea with bloody discharges were more pronounced in the Salmonella-infected birds on the FB1 diet. Mortality caused by Salmonella Gallinarum increased by 12% in the presence of FB1. Mean body weights in both the Salmonella-infected and FB1-fed groups were significantly lower than those of the controls at almost all intervals. Mean values of hemoglobin, packed cell volume, and total erythrocyte count were slightly higher in birds fed FB1 but were lower in the Salmonella Gallinarum groups fed FB1 and plain chick mash. Anemia was evident, between 5 and 10 days postinfection, in quail chicks infected with Salmonella Gallinarum alone. Total leukocyte counts were higher in Salmonella-infected and FB1-fed groups because of an increase in the number of heterophils and lymphocytes. However, the increase in lymphocyte response to infection was lower by 4.27%-30.09% between 3 and 21 days postinfection in the FB1-fed chicks compared with chicks infected with Salmonella Gallinarum. Alanine transaminase and total serum protein were slightly higher in both the infected and FB1-fed groups. This study revealed that the continuous presence of fumonisins in the diets of quail chicks might increase the susceptibility to or the severity of Salmonella Gallinarum infection.

Animals↗