Effects of Different Laser Pulse Regimes (Nanosecond, Picosecond and Femtosecond) on the Ablation of Materials for Production of Nanoparticles in Liquid Solution

Ultra-short laser pulse interaction with materials has received much attention from researchers in micro- and nanomachining, especially for the generation of nanoparticles in liquid environments, because of the straightforward method and direct application for organic solvents. In addition, the colloidal nanoparticles produced by laser ablation have very high purity—they are free from surfactants and reaction products or by-products. In this chapter, nanosecond, picosecond and femtosecond laser pulse durations are compared in laser material processing. Due to the unique properties of the short and ultra-short laser pulse durations in material processing, they are more apparent in the production of precision material processing and generation of nanoparticles in liquid environments

Laser Ablation in Different Environments and Generation of Nanoparticles

In the last two decades, pulsed-laser ablation has received attention from researchers in micro- and nanotechnology. During the development of laser ablation in materials processing, several media, such as vacuum, air, gases and liquids, have been used to improve the quality and quantity of laser machining and production of nanoparticles. The laser-ablation environment is important in order to control the average size and chemical compositions of nanoparticles. Conducting the laser-ablation process in liquid environments has become of increasing relevance for the production of precise and pure micromachining and nanomaterials. In addition, deionised water has been found to be the optimal environment to produce nanoparticles for bioapplications

Role of Laser Produced Silver Nanoparticles in Reversing Antibiotic Resistance in Some MultidrugResistant Pathogenic Bacteria

Silver nanoparticles (Ag NPs) were produced through nanosecond laser in deionized water. These nanoparticles were characterized by UV–VIS spectrometer and transmission electron microscopy. VITEK®2 compact system was used to identify Escherichia coli (ESBL strain) and Staphylococcus aureus (MRSA strain) as multidrug-resistance (MDR) bacteria. The antibacterial activity of Ag NPs, ampicillin (AMP), and their combinations was tested against both bacterial isolates through standard microbiological culturing techniques. Our data show that both of E. coli and S. aureus were highly resistant to AMP. Ag NPs alone reduced growth in both bacterial isolates considerably. Growth declined drastically in both bacteria when AMP was used in combination with Ag NPs. The minimal inhibitory concentration of combined agents for E. coli was 20 µg/ml Ag NPs + 1 mg AMP/ml and for S. aureus was 10 µg/ml Ag NPs + 1 mg AMP/ml. The results show that the Ag NPs have great potentials in enhancing the antimicrobial activities of drugs that used to be ineffective against MDR bacteria. Administering combinations of antibiotic(s) with AgNPs may help in treating patients suffering from infections caused by MDR bacteria. Further in vivo and in vitro investigations are required to evaluate the side effects of these combinations

Short Pulsed Laser Surface Texturing of Metallic Implants for Biomedical Applications

Surface texturing has been paid more attention by researchers for bio-applications due to its major role in controlling the integration of the implanted biomaterials and the surface fouling behaviour. Accurate control over the surface chemistry and physical characteristics significantly influence the interaction between the cells and the material’s surface regarding adhesion and migration. Short pulsed lasers have been widely used in modifying the surface topography and in generating structures ranging from micro-patterns to nanostructures. So far, bacterial and fouling activities and the biocompatibility of the implants’ laser-treated surfaces are not entirely understood. In this chapter, a brief overview of the lasers and techniques utilised in micro- and nano-surface modifications is presented, followed by a detailed discussion of the surface chemistry and topography effect on bacteria aggregation and adhesion. Also, the role of the laser-induced superficial patterns on the response and sensitivity of bio-implants will be explored in dept

THROMBOPROPHYLAXIS IMPACT IN PATIENTS UNDERGOING MAJOR ORTHOPEDIC SURGERY IN SUDAN

Objective: Venous thromboembolism is an important complication of major orthopedic surgery. The aim of present study was to investigate the efficacy of the currently used thromboprophylaxis protocol, determine the incidence of VTE post operatively and the risk factors behind it in patients undergoing major orthopedic surgery. Methods: A retrospective descriptive study for 403 patients underwent major orthopedic surgery from July 2013 to July 2014 in main hospitals in Khartoum state where major orthopedic surgery performed. Data were collected using observation checklist and analyzed using SPSS version 22 to study the association between the type of surgery, patient’s risk factors, choice and duration of thromboprophylaxis and development of VTE after major orthopedic surgery. Results: Total 403 patients were incorporated the study, 2.73% were diagnosed with DVT developed within 5 days post operatively. 1.64% of the patients not received any type of thromboprophylaxis, 0.27% wore compression stocking. Pharmacological methods were used in the rest of the patients, 96.72% administered to them enoxaparine. 75.95% of the patients presented with one or more than one risk factors for VTE other than the orthopedic surgery. 4% of patients received thromboprophylaxis for more than 14 days while 96% received it for 3-5 days. The incidence of DVT was higher in diabetic patients (p- value= 0.03) and hypertensive (p- value= 0.046) who aged ≥60 years. Conclusion: Results showed that VTE was a significant complication of major orthopedic surgery, despite the use of thromboprophylaxis and the incidence was 2.73% in our study.                             Peer Review History: Received 13 June 2020; Revised 25 June; Accepted 6 July, Available online 15 July 2020 Academic Editor: Essam Mohamed Eissa, Beni-Suef University, Egypt, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:                Reviewer's Comments: Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 7.0/10 Reviewer(s) detail: Dr. Michael Otakhor Erhunmwunse, St. Philomena Catholic Hospital, Nigeria, [email protected]  Francesco Ferrara, USL Umbria, Pharmacy Department, Perugia, Italy, [email protected]  Similar Articles: PREVALENCE OF CYTOMEGALOVIRUS IGG ANTIBODIES, POTENTIAL RISK FACTORS AND AWARENESS OF CONGENITAL CYTOMEGALOVIRUS AMONG FEMALE DOCTOR

Moringa oleifera Lam. (family Moringaceae) leaf extract attenuates high-fat diet-induced dyslipidemia and vascular endothelium dysfunction in Wistar albino rats

Purpose: To investigate the protective effect of methanol extract of Moringa oleifera leaves (MEMO) in high-fat diet (HFD)-induced dyslipidemia and vascular endothelium dysfunction. Methods: Dose-dependent attenuating effect of MEMO was tested at doses of 200 and 400 mg/kg/day in an in vivo model of HFD-induced dyslipidemia using rats whereas vascular endothelial reactivity was assessed in isolated rat aorta using ex vivo organ bath setup. Results: MEMO administration in HFD-induced dyslipidemic rats for 3 consecutive weeks, resulted in significant decrease in rat body weight, LW/BW and RFPW/BW ratio when compared to rats treated with HFD only where an increase in body weight was observed. Decrease in the average daily feed intake and significant reductions in waist, Lee index and BMI was also observed after MEMO treatment in HFD-induced dyslipidemic rats. Lipid profile data indicate that HFD group showed significant increase in total cholesterol, triglyceride, LDL and VLDL levels while HDL levels decreased significantly. On the other hand, MEMO treatment improved lipid profile compared to HFD group. Ex-vivo isolated aorta results revealed that MEMO treatment reversed HFD-induced endothelium dysfunction when compared to SD group. Conclusion: MEMO treatment produces dose-dependent improvement in lipid profile and vascular endothelium protection, thereby rationalizing its traditional medicine use in the treatment of dyslipidemia and cardiovascular related endothelial disorders

Caveolin-1 Variant Is Associated With the Metabolic Syndrome in Kuwaiti Children

Caveolin-1 (CAV1) variants have been suggested to be associated with obesity and related metabolic disorders, but information based on human studies is limited. In the present study, we aimed to investigate the potential association between the CAV1 rs1997623 C/A variant and metabolic syndrome (MetS) in Kuwaiti children. DNA from saliva samples collected from 1313 Kuwaiti children (mean age: 12 years) were genotyped using the TaqMan SNP genotyping assay. The classification of MetS was based on the presence/absence of four indicators; (1) central obesity, (2) elevated systolic or diastolic blood pressure, (3) low salivary high-density lipoprotein cholesterol (HDLC), and (4) high salivary glucose. In this study, children with MetS scored ≥3, children in the intermediate metabolic group scored 1 or 2 and children without MetS scored 0. About one-third of the children were obese. A total of 246 children (18.7%) were classified as having MetS; 834 children (63.5%) were in the intermediate metabolic group, and 233 children (17.7%) had no indication of MetS. Obesity was highly prevalent in the MetS group (91.9%) while 26.8% of children were obese in the intermediate metabolic group. None of the children were obese in the group without MetS. Analysis of the CAV1 rs1997623 variant revealed a significant association of the A-allele (p = 0.01, Odds Ratio (OR) = 1.66) and the heterozygous CA-genotype (p = 0.005, OR = 1.88) with MetS. Consistently, the A-allele (p = 0.002, OR = 1.71) and CA-genotype (p = 0.005, OR = 1.70) also showed significant association with the intermediate metabolic group. Furthermore, the A-allele (p = 0.01, OR = 1.33) and the CA-genotype (p = 0.008, OR = 1.55) were associated with low levels of saliva HDLC. Individuals who were heterozygous or homozygous for the variant (CA/AA) showed significantly lower levels of high HDLC compared to those harboring the CC-genotype (p = 0.023). Our study revealed a novel association of the CAV1 rs1997623 variant with the MetS and with low saliva HDLC levels in young Kuwaiti children and indicated the need for further in-depth studies to unravel the role of CAV1 gene in the genetic etiology of MetS

Global mortality associated with 33 bacterial pathogens in 2019: a systematic analysis for the Global Burden of Disease Study 2019

Background: Reducing the burden of death due to infection is an urgent global public health priority. Previous studies have estimated the number of deaths associated with drug-resistant infections and sepsis and found that infections remain a leading cause of death globally. Understanding the global burden of common bacterial pathogens (both susceptible and resistant to antimicrobials) is essential to identify the greatest threats to public health. To our knowledge, this is the first study to present global comprehensive estimates of deaths associated with 33 bacterial pathogens across 11 major infectious syndromes. Methods: We estimated deaths associated with 33 bacterial genera or species across 11 infectious syndromes in 2019 using methods from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, in addition to a subset of the input data described in the Global Burden of Antimicrobial Resistance 2019 study. This study included 343 million individual records or isolates covering 11 361 study-location-years. We used three modelling steps to estimate the number of deaths associated with each pathogen: deaths in which infection had a role, the fraction of deaths due to infection that are attributable to a given infectious syndrome, and the fraction of deaths due to an infectious syndrome that are attributable to a given pathogen. Estimates were produced for all ages and for males and females across 204 countries and territories in 2019. 95% uncertainty intervals (UIs) were calculated for final estimates of deaths and infections associated with the 33 bacterial pathogens following standard GBD methods by taking the 2·5th and 97·5th percentiles across 1000 posterior draws for each quantity of interest. Findings: From an estimated 13·7 million (95% UI 10·9–17·1) infection-related deaths in 2019, there were 7·7 million deaths (5·7–10·2) associated with the 33 bacterial pathogens (both resistant and susceptible to antimicrobials) across the 11 infectious syndromes estimated in this study. We estimated deaths associated with the 33 bacterial pathogens to comprise 13·6% (10·2–18·1) of all global deaths and 56·2% (52·1–60·1) of all sepsis-related deaths in 2019. Five leading pathogens—Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae, Klebsiella pneumoniae, and Pseudomonas aeruginosa—were responsible for 54·9% (52·9–56·9) of deaths among the investigated bacteria. The deadliest infectious syndromes and pathogens varied by location and age. The age-standardised mortality rate associated with these bacterial pathogens was highest in the sub-Saharan Africa super-region, with 230 deaths (185–285) per 100 000 population, and lowest in the high-income super-region, with 52·2 deaths (37·4–71·5) per 100 000 population. S aureus was the leading bacterial cause of death in 135 countries and was also associated with the most deaths in individuals older than 15 years, globally. Among children younger than 5 years, S pneumoniae was the pathogen associated with the most deaths. In 2019, more than 6 million deaths occurred as a result of three bacterial infectious syndromes, with lower respiratory infections and bloodstream infections each causing more than 2 million deaths and peritoneal and intra-abdominal infections causing more than 1 million deaths. Interpretation: The 33 bacterial pathogens that we investigated in this study are a substantial source of health loss globally, with considerable variation in their distribution across infectious syndromes and locations. Compared with GBD Level 3 underlying causes of death, deaths associated with these bacteria would rank as the second leading cause of death globally in 2019; hence, they should be considered an urgent priority for intervention within the global health community. Strategies to address the burden of bacterial infections include infection prevention, optimised use of antibiotics, improved capacity for microbiological analysis, vaccine development, and improved and more pervasive use of available vaccines. These estimates can be used to help set priorities for vaccine need, demand, and development. Funding: Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Health and Social Care, using UK aid funding managed by the Fleming Fund