Effect of Physical and Chemical Parameters on the Activity of Purified Phosphatase Enzyme Produced by Bacillus cereus

Phosphorus is one of the most important nutrients for plant growth and development. This study aimed to survey the optimum condition for phosphatase enzyme production, purified and studied its properties. Phosphatase enzyme activity was determined by end point method. Phosphatase enzyme was obtained from Bacillus cereus EME 66 isolate. The enzyme was purified and characterized, using a three-step purification procedure with 12.3-fold. The phosphatase enzyme was partially purified using ammonium sulfate fractionation followed by ultrafiltration. The acid phosphatase is a monomer protein purified gel filtration to 5.6 fold. Results showed that the optimum temperature for the purified enzyme activity was 60 °C and it was stable at temperatures below 60 °C. This enzyme was stable between pH 4.0-6.0, and the optimal pH activity was found to 5.0. The activity of the enzyme enhanced by heavy metals (Fe3+, Cu2+, Ca2+, Mg2+ and K+). The enzyme activity was strongly inhibited by heavy metals Zn2+. The present article reveals on enzymatic characterization of acid phosphatase enzyme

NATURAL ANTIMICROBIALS IN THE PIPELINE AND POSSIBLE SYNERGISM WITH ANTIBIOTICS TO OVERCOME MICROBIAL RESISTANCE

The unresponsive use of antibiotics led to the appearance of multiple drug-resistant bacteria strains. Studying the mechanism by which bacteria can resist antibiotics, the so called quorum sensing and biofilm formation, enabled the researchers to find bioactive compounds, derived from eukaryotes and prokaryotes. The disrupt of this mechanism is called quorum sensing inhibitors or quorum quenchers. This article provides an overview on the current research done on such bioactive compounds, the possible use of them as antibiotic alternatives, what are the advantage and disadvantages, the source from which it has been extracted, and how it may succeed to overcome bacterial resistance. The recommendation of researchers is to use some of these natural antimicrobial compounds combined to lower doses of antibiotics for treatment, the fastest way to limit the adverse effects of the exploitation of antibiotics and to avoid bacterial resistance

In vitro evaluation of antioxidant, biochemical and antimicrobial properties of biosynthesized silver nanoparticles against multidrug-resistant bacterial pathogens

Interest in nanoparticles has increased rapidly over the last few years, becoming one of the most compelling scopes of research fields. The microbial methods utilized for biomediated nanoparticle synthesis are the most favourable and well-established substitute for the classic chemical and physical methods. In this study, silver nanoparticles (AgNPs) were biosynthesized by reducing Ag+ ions using a cell-free supernatant derived from Bacillus aerius culture and silver nitrate (AgNO3) solution as a precursor. The reaction mixture exhibited a colour change from yellow to brown, and ultraviolet-visible spectroscopy showed a surface plasmon resonance peak at 420 nm. The nanoparticles were monodispersed and spherical with an average particle size of 20.12–29.48 nm as determined by transmission electron microscopy. The Fourier transform infrared spectrum revealed the capping of AgNPs with biomolecular compounds that were responsible for the reduction of AgNO3 to AgNPs. The biosynthesized AgNPs had powerful and potent antibacterial activity against many multidrug-resistant bacterial pathogens. Moreover, the in vitro dose-dependent antioxidant activity of the aqueous extract of AgNP components showed good antioxidant activity as compared to the standard antioxidant ascorbic acid. These outcomes support the advantages of green techniques for synthesizing AgNPs that can be utilized effectively in the production of potential antioxidant and antibacterial AgNPs for commercial application

Characteristics of Immobilized Urease on Grafted Alginate Bead Systems

This study evaluated the biological importance of immobilized urease enzyme over the free urease. The support material used for urease immobilization was alginate. Generally, the immobilization of urease in alginate gel showed a marked increase in Km and Vmax. However, the immobilized urease showed higher thermal stability than that of free enzyme. The rate of thermal inactivation of the immobilized enzyme decreased due to entrapment in gel matrix. Also, the activity of the immobilized urease was more stable in retention than that of the free enzyme during the storage in solution, although the activity of the immobilized enzyme was lower in comparison with the free enzyme. A stable immobilized system and long storage life are convenient for applications that would not be feasible with a soluble enzyme system. These results highlighted the technical and biochemical benefits of immobilized urease over the free enzyme

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research