5 research outputs found
Biosynthesise, Characterization and Antibacterial activity of Silver nanoparticles by Soil fungi Pencillium sps.
Microbial synthesis of nanoparticles is an eco-friendly green chemistry approach that correlates with nanotechnology and microbial biotechnology. Exposure of fungal biomass to aqueous 1Mm AgNO3 solution resulted in the reduction of the metal ions by the nitrate reductase enzyme present in the cell wall membranes and formation of silver nanoparticles. Synthesized silver nanoparticles were characterized using UV-visible spectroscopy, SEM, TEM and FTIR analysis. The synthesed silver nanoparticles were exhibited an excellent antibacterial activities against both Gram negative and Gram positive pathogenic bacterial strains which causes the diseases in human being
Endoplasmic Reticulum Homeostasis Regulates TLR4 Expression and Signaling in Mast Cells
The endoplasmic reticulum (ER) is a dynamic organelle that responds to demand in secretory proteins by undergoing expansion. The mechanisms that control the homeostasis of ER size and function involve the activation of the unfolded protein response (UPR). The UPR plays a role in various effector functions of immune cells. Mast cells (MCs) are highly granular tissue-resident cells and key drivers of allergic inflammation. Their diverse secretory functions in response to activation through the high-affinity receptor for IgE (FcεRI) suggest a role for the UPR in their function. Using human cord blood-derived MCs, we found that FcεRI triggering elevated the expression level and induced activation of the UPR transducers IRE1α and PERK, accompanied by expansion of the ER. In mouse bone marrow-derived MCs and peritoneal MCs, the ER underwent a more moderate expansion, and the UPR was not induced following MC activation. The deletion of IRE1α in mouse MCs did not affect proliferation, survival, degranulation, or cytokine stimulation following FcεRI triggering, but it did diminish the surface expression of TLR4 and the consequent response to LPS. A similar phenotype was observed in human MCs using an IRE1α inhibitor. Our data indicate that the ER of MCs, primarily of humans, undergoes a rapid remodeling in response to activation that promotes responses to TLR4. We suggest that IRE1α inhibition can be a strategy for inhibiting the hyperactivation of MCs by LPS over the course of allergic responses
Utility of tissue Xpert-Mtb/Rif for the diagnosis of intestinal tuberculosis in patients with ileocolonic ulcers
Introduction: Data on the use of Xpert Mtb/Rif for the diagnosis of intestinal tuberculosis is sparse. We report on the utility of Xpert Mtb/Rif testing for diagnosis of intestinal tuberculosis (ITB) in patients with ileocecal ulcers Methodology: We performed a retrospective analysis of patients with ileocecal ulcers and suspected to have ITB and in whom testing of intestinal tissue for Xpert Mtb/Rif was performed. The patients were divided into two groups: those with a final diagnosis of intestinal tuberculosis and those with other diagnosis. These patients were compared for clinical features and presentation. The sensitivity, specificity, positive predictive value, and negative predictive value of Xpert Mtb/Rif for the diagnosis of ITB were calculated. Results: Of the 40 patients studied, 23 were women and the mean age was 32.92 ± 12.78 years. Abdominal pain was present in 33 (88.5%) patients and diarrhea in 12 (30%). A total of 25 patients had underlying ITB whereas 15 patients had other diagnoses (Crohn’s disease, amebiasis, nonspecific ileitis, etc.). The sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of GeneXpert-Mtb/Rif was 32% (CI: 14.95–53.50%), 100% (78.2–100), 46.88% (40.27–53.59%), 100 & 57.50 (40.89–72.89%) respectively. Conclusion: A positive GeneXpert-Mtb/Rif helps in the diagnosis of ITB, but the sensitivity is low
Endoscopic drainage versus percutaneous drainage for the management of infected walled-off necrosis: a comparative analysis
Background: Comparative data on percutaneous catheter drainage (PCD) vs EUS-guided drainage (EUS-D) for management of symptomatic walled-off-necrosis (WON), specially infected WON with/without organ failure(OF) is limited. Methods: Patients with symptomatic WON were divided into two groups of PCD and EUS-D, depending on the modality of drainage. Resolution of OF, adverse events, and other outcome measures were recorded. The two modalities were compared among infected WON sub-cohort and also degree of solid component (SC). Results: 218 patients (175 males; 80.3%) were included who underwent either PCD (n = 102) or EUS-D (n = 116). Clinical success was significantly higher in the EUS-D group (92.1% vs 64.6%; p < 0.0001) and even for infected WON (n = 128) (p = 0.004), with higher (p = 0.007) and faster (p < 0.0001) OF resolution. Other outcome measures including mortality were significantly higher in the PCD group. Among subgroups, PCD with >40% SC had the worst clinical success/OF resolution rates, while EUS-D with <40% SC had the best outcomes. Conclusion: EUS-D should be preferred over PCD in the management of WON, infected or otherwise, for higher clinical success, and higher/faster resolution of OF. PCD should be avoided in WON with>40% SC
Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study
Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC). Findings In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683–0·717]). Interpretation In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required. Funding British Journal of Surgery Society