Preparation of cyclodextrin nanoparticles and evaluation of its effect on the capacitation of bovine spermatozoa used in the in vitro fertilization

This study was conducted to produce nanosized cyclodextrin (NCD) and assess its effect on bovine spermatozoa during In vitro fertilization (IVF) to optimize the capacitation media for successful IVF. Therefore, Four cyclodextrin formulations were prepared and characterized. Data analysis revealed the best formula (F2) showed a smallest particle size (15 nm), zeta potential (-37 mv), and higher yield percentages (95%) was selected for spem capacitation. Motile spermatozoa were separated from frozen-thawed semen by a swim-up procedure and capacitated in IVF-TALP medium with different formulae of NCD or CD or without treatments (control) and incubated for 3hours(hr) at 38°C and evaluated every one (hr) interval. Data analysis revealed that the formulation of cyclodextrin nanoparticles (F2) after (2hr) incubation in the media gave best effect on sperm capacitation and acrosme reaction (AR) and effect of sperm treated with NCD on fertilization rate was evaluated. The results showed that the proportion of Oocytes fertilized was increased significantly in F2 (60%) than in the control (35%), and cyclodextrin group (50%) groups (p<0.05). It could be inferred from this investigation that cyclodextrin nanoparticles can be used for biomedical interventions in bovine spermatozoa. NCD improve sperm motility, viability, and (AR), also fertilization rate of sperm treated with NCD increase. So NCD gave positive effect on sperm functions during IVF.

Expression and purification of recombinant Shiga toxin 2B from Escherichia coli O157:H7

Enterohemorrhagic Escherichia coli are important human food-borne pathogens. Recently, Shiga toxinproducing E. coli (STEC) causes life-threatening hemolytic-uremic syndrome (HUS). In this study, Stx2B gene, a subunit of Shiga toxin, was amplified via polymerase chain reaction (PCR) from the chromosomal DNA of clinical fecal sample using appropriate primers. The PCR product was cloned to commercially available plasmid pH6HTN His6HaloTag® T7 containing two purification tags, namely, six histadine tag and Halo tag. The integrity of the constructed plasmid was confirmed using restriction enzyme mapping and sequencing. Then, Stx2B protein expressed after induction with isopropyl β-D-1-thiogalactopyranoside (IPTG) in E. coli JM109 (DE3) under the control of the T7 promotor. The two step purification trains were used to purify native Stx2B. First step purification was Ni-immobilized metal ion affinity chromatography (IMAC) column, followed by second step using HaloLink resin. The native Stx2B was obtained after column cleavage of halo-tag using HaloTEV protease. Maximum protein expression of Stx2B economically was obtained using 1 mM IPTG for 4 h at 37°C. Protein identity was confirmed by a band at ~11.4 kDa using 15% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and StxB2 yield was 450 μg ml-1 confirmed by Bradford assay. Recombinant Stx2B protein was produced in highly pure yield using HaloTag technology.Key words: Escherichia coli O157:H7, StxB gene, expression, HaloTag technology, purification

The Effectiveness Of Non Invasive Hemodynamic Parameters In Detection Of Spinal Anesthesia Induced Hypotension During Cesarean Section

Introduction: Hypotension is the most frequent consequence of spinal anesthesia in cesarean section. It results in harmful effects on mother and newborn.Aim: This study aim was to evaluate the correlation of positional changes in hemodynamic (heart rate and blood pressure) measured before spinal anesthesia in anticipation of occurrence of hypotension throughout cesarean delivery.Methods: 100 ASA grade I parturient were selected for this prospective observational study. Preoperative sociodemographic data, parity, and hemodynamic parameters were recorded including changes in systolic, diastolic, mean arterial blood pressure, and heart rate after positional shift from supine to lateral and sitting positions. Intraoperative, occurrence of hypotension was noted.Results: With hypotension as the dependent variable, the age, parity, heart rate at supine position, and changes in (heart rate, systolic, diastolic and mean arterial blood pressure) from supine to lateral position, and from supine to sitting position had high statistical significant negative correlation with blood pressure as P value <.05. Multivariate logistic analysis to assess predictors of hypotension concluded that changes in hemodynamic variable from supine to lateral position only significant predictor were (Δ heart rate, Δ diastolic and Δ mean blood pressure), and changes in hemodynamic variable from supine to sitting position only significant predictor were (Δheart rate and Δ diastolic blood pressure).Discussion: Elevated sympathetic activity before neuraxial anesthesia was associated with higher risk for post-spinal hypotension. The great variability in hemodynamic after positional change indicates higher sympathetic activity to blood vessels. The high rise in the autonomic activity, the higher the risk for post-spinal hypotensionConclusion: Age, parity, and positional changes in hemodynamic were correlated with blood pressure reading after spinal anesthesia during cesarean delivery

Preparation of progesterone nanoparticles and evaluation of its effect on the capacitation of Bovine spermatozoa used in the in Vitro Fertilization

Progesterone (P) has been reported to affect several sperm functions especially capacitation and acrosome reaction. The main problem of (P) is its low aqueous solubility. So formulation of progesterone nanoparticles (PN) will enhance its solubility. This study was conducted to produce nanosized progesterone (NP) and assess its biocompatibility. Therefore, nine progesterone formulations were prepared and characterized. Data analysis revealed only one formula of P showed nanosized particle (1-100 nm) with an average particle size (95±5 nm), and spherical shape as seen by Transmission Electron Microscope(TEM). Motile spermatozoa were separated from frozen-thawed semen by a swim-up procedure and capacitated in IVF-TALP medium with NP or P or without treatments (control) and incubated for 3h at 38°C and evaluated every 1 hour (h) interval. Ovarian oocytes were matured and fertilized in vitro with frozen-thawed bull sperm capacitated in vitro with NP or P or control (without NP, P) and incubated at 39C in 5% CO2 incubator for 24h and then examined for evidence of fertilization. In conclusion, this study demonstrates that nanosized progesterone is highly efficient for sperm capacitation. In addition to the use of nanosized progesterone in sperm capacitation produces more fertilized oocytes than the progesterone after In Vitro Fertilization (IVF)

Review Multi Pass Friction Stir Processing

The aim of this article is to provide a review of multiple passes friction stir processing technology and their effect on the microstructure refinement, improving mechanical properties furthermore enhancement of reducing distortion and defects in materials. Multi-pass FSP achieves uniform dispersion of reinforcement particles in the metal matrix composites. The present paper reviews the work done in the above mentioned areas and concludes the effect of multi-pass FSP on the mechanical properties

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Solar-based physicochemical-biological processes for the treatment of toxic and recalcitrant effluents

Wastewater treatment is a worldwide necessity that is even more crucial to countries deprived from abundant fresh water sources or unable to afford advanced and costly processes. With this perspective, this thesis was conducted within an Egyptian-Swedish research collaboration that aimed to develop solar-based (as free renewable energy source available locally) process for hazardous wastewater treatment. A local coke factory generating a phenol-laden toxic wastewater was used as model. Solar-based biological (sunlight being used to power algal photosynthesis for oxygen production) or physicochemical (sunlight being used to power photodegradation) treatments were first tested independently before the best options were combined in a sequential process. A p-nitrophenol (PNP)-degrading Arthrobacter sp., a phenol-degrading Alcaligenes sp. and a Chlorella vulgaris were isolated from the coke wastewater plant. Alcaligenes sp. could biodegrade up to 1200 mg phenol l-1 as well as other aromatic compounds such polycyclic aromatic hydrocarbon (PAHs). Its growth on phenol was well described by the Haldane kinetic model. Arthrobacter sp. could degrade 120 mg PNP l-1 but was inhibited at concentrations above. C. vulgaris was capable to grow in the presence of 300 or 20 mg l-1 of phenol or PNP, respectively, but was totally inhibited at PNP concentrations higher than 25 mg l-1. Sunlight was advantageously used to reduce the aeration costs and improve the safety (less risk of hazardous pollutants spreading) by supporting photosynthetic oxygen production by C. vulgaris during the aerobic biodegradation of a simulated industrial wastewater (325 mg phenol l-1 and 500 mg NH4+ l-1) by Alcaligenes sp. Continuous treatment at the 3.6 d HRT (Hydraulic Retention Time) in a single stage photobioreactor supported phenol and NH4+ removals of 58 and 18%, respectively. Algae fertilization with 8 g NaHCO3 l-1 increased these values to 100 and 29%, respectively. However, biological treatment of a mixture of phenol and PNP at 100 and 50 mg l-1 or real coke wastewater under photosynthetic aeration was not possible due to algal inhibition. Hence, it was necessary to pre-treat the effluents by photochemical treatment. Microbial inhibition was also observed during biological treatment (under classical aeration) with acclimated (biofilm consortium) or non acclimated (activated sludge microflora) of a mixture of 4-chlorophenol (CP), 2,4-dichlorophenol (DCP), 2,4,6-trichlorophenol (TCP), and pentachlorophenol (PCP) at an initial concentration of 50 mg l-1 each. UV irradiation was efficient to reduce the toxicity of this mixture and thereby allow the complete biodegradation of the remaining pollutants by both inocula. Evidence was however found that the pollutants were partially photodegraded into toxic and non-biodegradable products. UV irradiation of a similar mixture of chlorophenols (CPs) initially supplied at 100 mg l-1 each even caused the release of toxic photoproducts that contributed to inhibit the subsequent biological step. Interestingly, the photoproducts released from solutions of individually supplied CPs could be subsequently biodegraded, showing that results from studies conducted on single contaminants cannot be extrapolated to mixtures. Photochemical pre-treatments (UV/TiO2/H2O2, UV/H2O2, or UV/TiO2), significantly improved the removal of all pollutants. Photochemical degradation was well described with pseudo first order kinetics and UV/TiO2/H2O2 treatment supported the highest pollutant photodegradation rates. UV/TiO2 and UV/H2O2 were efficient to detoxify both CPs mixtures (50 or 100 mg l-1) and allow the subsequent biodegradation of the remaining 4CP and DCP, yet evidence was found that recalcitrant photoproducts (some of which were chlorinated) were formed during these treatments. By comparison, combined UV/TiO2/H2O2 ? biological treatment of both CPs mixtures allowed complete pollutant removal, detoxification, dechlorination, and nearly complete COD removal. It should therefore be regarded as the safest treatment option. A fully solar-based combined photochemical - biological treatment was finally used to efficiently treat various mixtures of pollutants, as well as synthetic and real coke wastewater. UV photolysis was efficient to sufficiently detoxify a mixture of phenol, TCP and PCP and coke wastewater (1st sampling campaign) and support the subsequent biodegradation of the remaining pollutants under photosynthetic aeration. It was however inefficient to detoxify a mixture of 100 mg phenol l-1 and 50 mg PNP l-1. The combined UV/TiO2-algal based biological treatment of this mixture efficiently removed all the pollutants and completely detoxified the effluent. Based on the treatment efficiencies of different mixtures of pollutants as well as artificial or real coke wastewaters, the combined treatments tested could be ranked in the following order of decreasing efficiency: UV/TiO2/H2O2-biological > UV/TiO2-biological ~ UV/H2O2-biological > UV-biological. However, these pre-treatment steps can also be inversely ranked from the most to the least economical as UV < UV/TiO2 < UV/H2O2 < UV/TiO2/H2O2. UV/TiO2 is an interesting cost-efficient alternative (in cases not recalcitrant photoproducts are formed) but its large scale implementation remains limited by the technical difficulties in immobilizing or recycling the catalyst. More research is therefore needed to determine the most cost-efficient method in regards to the affordable risks. More research is also needed to improve algal-recovery to improve the process (biomass control, biomass reuse) and achieve satisfactory effluent quality

Unsupervised query reduction for efficient yet effective news background linking

In this article, we study efficient techniques to tackle the news background linking problem, in which an online reader seeks background knowledge about a given article to better understand its context. Recently, this problem attracted many researchers, especially in the Text Retrieval Conference (TREC) community. Surprisingly, the most effective method to date uses the entire input news article as a search query in an ad-hoc retrieval approach to retrieve the background links. In a scenario where the lookup for background links is performed online, this method becomes inefficient, especially if the search scope is big such as the Web, due to the relatively long generated query, which results in a long response time. In this work, we evaluate different unsupervised approaches for reducing the input news article to a much shorter, hence efficient, search query, while maintaining the retrieval effectiveness. We conducted several experiments using the Washington Post dataset, released specifically for the news background linking problem. Our results show that a simple statistical analysis of the article using a recent keyword extraction technique reaches an average of 6.2× speedup in query response time over the full article approach, with no significant difference in effectiveness. Moreover, we found that further reduction of the search terms can be achieved by eliminating relatively low TF-IDF values from the search queries, yielding even more efficient retrieval of 13.3× speedup, while still maintaining the retrieval effectiveness. This makes our approach more suitable for practical online scenarios. Our study is the first to address the efficiency of news background linking systems. We, therefore, release our source code to promote research in that direction