4,844 research outputs found
Non-universal dependence of spatiotemporal regularity on randomness in coupling connections
We investigate the spatiotemporal dynamics of a network of coupled nonlinear
oscillators, modeled by sine circle maps, with varying degrees of randomness in
coupling connections. We show that the change in the basin of attraction of the
spatiotemporal fixed point due to varying fraction of random links , is
crucially related to the nature of the local dynamics. Even the qualitative
dependence of spatiotemporal regularity on changes drastically as the
angular frequency of the oscillators change, ranging from monotonic increase or
monotonic decrease, to non-monotonic variation. Thus it is evident here that
the influence of random coupling connections on spatiotemporal order is highly
non-universal, and depends very strongly on the nodal dynamics.Comment: 9 pages, 4 figure
Comparison of double disc and combined disc method for the detection of extended spectrum beta lactamases in enterobacteriaceae
Objective: To compare double disc approximation and combined disc method for their ability to detect extended spectrum b lactamase (ESBL) production in enterobacteriaceae and determine the percentage of isolates which are falsely reported as sensitive in absence of ESBL detection, in a clinical microbiology laboratory of a tertiary care hospital between September-October 2002. Methods: Selected isolates were identified according to standard biochemical tests. Disc susceptibility tests were performed according to NCCLS. ESBL detection by combined disc [cefotaxime (30 ug) versus cefotaxime plus clavulanate (30+10 ug)] was compared with detection using double discs [amoxy-clavulanic acid (20+10 ug) and aztreonam (30 ug) applied 10 mm apart]. Results were interpreted according to NCCLS and analysed on SPSS version 10. Results: ESBL production was detected in 140 (30%) isolates by combined disc method and 139 (29.5%) by double disc method. There was no significant difference between two methods. Of the ESBL positive isolates 41 (29%) gave zone diameters that were within the sensitivity range cutoff and would have been falsely reported as being beta lactam sensitive in absence of ESBL detection. Conculsion: ESBL detection should be routinely performed in clinical laboratories as false reporting would result in treatment failure despite in vitro sensitivity. No difference was found between the combined disc and double disc methods hence either of two could be used
Structure of mouse IP-10, a chemokine
The structure of mouse IP-10 shows a novel tetrameric association
Comparison of different phenotypic methods of detection of methicillin resistance in staphylococcus aureus with the molecular detection of mec-a gene
OBJECTIVE: To evaluate accuracy, cost-effectiveness and ease to perform different phenotypic methods i.e. Cefoxitin 30 microg disc, Oxacillin 1microg disc and Oxacillin agar screening plate (6microg/ml ) for early and accurate identification of MRSA by comparing with the detection of mec-A gene in our clinical isolates. DESIGN: A comparative study. PLACE AND DURATION OF STUDY: Clinical samples submitted in the Clinical Microbiology Laboratory at Aga Khan University Hospital, Karachi, from 1st August to 31st October 2006. MATERIAL AND METHODS: Out of 200 clinical samples, conventional Polymerase chain reaction (PCR) was done on 62 pure biochemically identified S. aureus isolates for mec-A gene detection. Phenotypic methods for detecting methicillin sensitivity (Cefoxitin 30 microg disc, Oxacillin 1 microg disc and Oxacillin agar screening plate) were also used according to the recommended incubation time, duration and temperature on the same isolates. RESULTS: Out of 62 isolates of S. aureus, mec-A gene were detected (MRSA) in 32, whereas 30 were mec-A gene negative (MSSA). Cefoxitin disc and agar screening plate correctly identify all MRSA isolates with the sensitivity and specificity of 100%. Single isolate was false, positively detected as sensitive with Oxacillin 1microg disc, due to which, the sensitivity and negative predictive value of this method were reduced to 96.9% and 96.8% respectively, while positive predictive value and specificity remained 100%. CONCLUSION: Comparing different phenotypic methods for MRSA screening in routine microbiology laboratory, Cefoxitin disc and Oxacillin agar screening has better sensitivity and specificity comparative to Oxacillin disc. However, Cefoxitin disc can be preferred especially for small laboratories because it is easy to perform, do not require special technique and media preparation is consequently more cost-effective
PreImplantation Factor (PIF) promotes HLA-G, -E, -F, -C expression in JEG-3 choriocarcinoma cells and endogenous progesterone activity
BACKGROUND: Pregnancy success requires mandatory maternal tolerance of the semi/allogeneic embryo involving embryo-derived signals. Expression levels of PreImplantation Factor (PIF), a novel peptide secreted by viable embryos, correlate with embryo development, and its early detection in circulation correlates with a favourable pregnancy outcome. PIF enhances endometrial receptivity to promote embryo implantation. Via the p53 pathway, it increases trophoblast invasion, improving cell survival / immune privilege. PIF also reduces spontaneous and LPS-induced foetal death in immune naïve murine model.
AIMS: To examine if PIF affects gene expression of human leukocyte antigen (HLA)-G, -E -F and -C in JEG-3 choriocarcinoma cells, and to examine the influence of PIF on local progesterone activity.
Methods: PIF and progesterone (P4) effects on JEG-3 cells surface and intracellular HLA molecules was tested using monoclonal antibodies, flow cytometry, and Western blotting. PIF and IL17 effects on P4 and cytokines secretion was determined by ELISA. PIF and P4 effects on JEG-3 cells proteome was examined using 2D gel staining followed by spot analysis, mass spectrometry and bioinformatic analysis.
RESULTS: In cytotrophoblastic JEG-3 cells PIF increased intracellular expression of HLA-G, HLA-F, HLA-E and HLA-C and surface expression of HLA-G, HLA-E and HLA-C in dose and time dependent manner. In case of HLA-E, F confirmed also by Western blotting. Proteome analysis confirmed an increase in HLA-G, pro-tolerance FOXP3+ regulatory T cells (Tregs), coagulation factors and complement regulator. In contrast, PIF reduced PRDX2 and HSP70s to negate oxidative stress and protein misfolding. PIF enhanced local progesterone activity, increasing steroid secretion and the receptor protein. It also promoted the secretion of the Th1/Th2 cytokines (IL-10, IL-1β, IL-8, GM-CSF and TGF-β1), resulting in improved maternal signalling.
CONCLUSION: PIF can generate a pro-tolerance milieu by enhancing the expression of HLA molecules and by amplifying endogenous progesterone activity.
A Fast-Track clinical trial for autoimmune disease has been satisfactorily completed. The acquired data warrants PIF use for the treatment of early pregnancy disorders
The many guises of primary hyperparathyroidism… an unchanged scenario
Abstract OBJECTIVE:
To study the causes, characteristics and outcome of treatment of patients with primary hyperparathyroidism. METHODS:
This retrospective cohort analysis was conducted at the Jinnah Postgraduate Medical Centre, Karachi, and comprised data of patients with primary hyperparathyroidism between 2004 and 2014. .SPSS 17 was used for data analysis. RESULTS:
Of the 25 patients,1(4%)was male and 24(96%) were female. The overall mean age was 41.72±15.9 years, with a mean duration of symptoms of 4.1±3.3 years. The mean pre-operative parathyroid hormone level was 879.48±793.51 pg/ml. Skeletal manifestations were reported in 17(68%) patients, whereas 4(16%) patients had renal stone disease. Besides, 2(8.0%) patients presented with severe abdominal pain, 1(4%) had asymptomatic hypercalcaemia and 1(4%) patient presented with headache and was diagnosed as parathyroid adenoma in the context of multiple endocrine neoplasia type 2A. All patients underwent parathyroidectomy. A solitary adenoma was reported in 23(92%) patients, carcinoma in 1(4%) and an adenoma with hyperplasia of other glands in 1(4%) patient. CONCLUSIONS:
A high index of suspicion is required for early diagnosis of primary hyperparathyroidism
Impact of conflict on maternal and child health service delivery: A country case study of Afghanistan
Introduction: Since decades, the health system of Afghanistan has been in disarray due to ongoing conflict. We aimed to explore the direct effects of conflict on provision of reproductive, maternal, newborn, child and adolescent health and nutrition (RMNCAH&N) services and describe the contextual factors influencing these services.Method: We conducted a quantitative analysis of secondary data on RMNCAH&N indicators and undertook a supportive qualitative study to help understand processes and contextual factors. For quantitative analysis, we stratified the various provinces of Afghanistan into minimal-, moderate- and severe conflict categories based on battle-related deaths from Uppsala Conflict Data Program (UCDP) and through accessibility of health services using a Delphi methodology. The coverage of RMNCAH&N indicators across the continuum of care were extracted from the Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Survey (MICS). The qualitative data was captured by conducting key informant interviews of multi-sectoral stakeholders working in government, NGOs and UN agencies.Results: Comparison of various provinces based on the severity of conflict through Delphi process showed that the mean coverage of various RMNCAH&N indicators including antenatal care (OR: 0.42, 95%CI: 0.32-0.55), facility delivery (OR: 0.42, 95%CI: 0.32-0.56), skilled birth attendance (OR: 0.43, 95%CI: 0.33-0.57), DPT3 (OR: 0.26, 95% CI: 0.20-0.33) and oral rehydration therapy (OR: 0.37, 95% CI: 0.25-0.55) was significantly lower for severe conflict provinces when compared to minimal conflict provinces. The qualitative analysis identified various factors affecting decision making and service delivery including insecurity, cultural norms, unavailability of workforce, poor monitoring, lack of funds and inconsistent supplies. Other factors include weak stewardship, capacity gap at the central level and poor coordination at national, regional and district level.Conclusion: RMNCAH&N service delivery has been significantly hampered by conflict in Afghanistan over the last several years. This has been further compromised by poor infrastructure, weak stewardship and poor capacity and collaboration at all levels. With the potential of peace and conflict resolution in Afghanistan, we would underscore the importance of continued oversight and integrated implementation of sustainable, grass root RMNCAH&N services with a focus on reaching the most marginalized
Choroidal vascularity map in unilateral central serous chorioretinopathy: A comparison with fellow and healthy eyes
Background: To map the choroidal vascularity index and compare two eyes in patients with unilateral central serous chorioretinopathy (CSCR). Methods: This was a retrospective, observa-tional study performed in patients with unilateral CSCR. Choroidal thickness (CT) and Choroidal vascularity index (CVI) were measured and mapped in various zones according to the early treatment diabetic retinopathy (ETDRS) grid. Results: A total of 20 CSCR patients (20 study and 20 fellow eyes) were included in the study. Outer nasal region CT was seen to be significantly lower than central CT (p = 0.042) and inner nasal CT (p = 0.007); outer ring CT was significantly less than central (p = 0.04) and inner ring (p = 0.01) CT in CSCR eyes. On potting all the CVI values against the corresponding CT values, a positive correlation was seen in CSCR eyes (r = 0.54, p < 0.01), which was slightly weaker in fellow eyes (r = 0.3, p < 0.01) and a negative correlation was seen in healthy eyes (r = −0.262, p < 0.01). Conclusions: Correlation between CVI and CT was altered in CSCR eyes as compared to fellow and normal eyes with increasing CVI towards the center of the macula and superiorly in CSCR eyes
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