48 research outputs found

    Antimicrobial activity of silver-carbon nanoparticles on the bacterial flora of bull semen

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    The spermicidal effects of silver nanoparticles (AgNPs) hinder its application in the field of artificial insemination. In this study, silver-carbon NPs (Ag@C NPs) was synthesized and applied as an alternative antibiotic agent for bull semen extender. Ag@C NPs were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic absorption flame spectroscopy, transmission electron microscope (TEM), and high-resolution TEM (HR-TEM). Data analysis revealed the successful synthesis of Ag@C NPs with a particle size of 1–5 nm (average particle size of 2.5 nm) embedded into carbon. The antimicrobial activity of Ag@C NPs was tested against bacteriospermia of fresh semen collected from five fertile bulls (three ejaculates/bull). Escherichia coli (E. Coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa) were isolated from fresh semen samples and identified by culture, staining, and conventional biochemical tests. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Ag@C NPs against bacteriospermia was determined at 5 and 37 °C. Ag@C NPs showed efficient antimicrobial activity (MIC: 3.125–12.5 μg/mL) against the tested strains and strong bactericidal effect on S. aureus, and P. aeruginosa (MBC: 3.125 μg/mL), with no detrimental effect (P ˃ 0.05) on the percentage of sperm motility (70.71 ± 4.82; 74.65 ± 4.46), plasma membrane integrity (68.39 ± 4.31; 72.38 ± 4.91), acrosome integrity (88.40 ± 13.21; 86.77 ± 14.23), and normal sperm morphology (86.85 ± 7.43; 87.82 ± 8.15) at concentrations of 15 and 30 μg/mL, respectively, after a cold storage of 48 h. However, Ag@C NPs showed a detrimental effect on sperm parameters in a dose dependent manner at concentrations ≥60 μg/mL. Ag@C NPs showed no adverse effect on the sperm’s ultrastructure with limited sperm internalization at MIC. In conclusion, Ag@C NPs could be used as an alternative antibiotic agent for bull semen extender without a significant cytotoxic effect on the sperm during cold storage. However, further investigations for their effects on embryo production and female genitalia are still required

    Simulations of galactic dynamos

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    We review our current understanding of galactic dynamo theory, paying particular attention to numerical simulations both of the mean-field equations and the original three-dimensional equations relevant to describing the magnetic field evolution for a turbulent flow. We emphasize the theoretical difficulties in explaining non-axisymmetric magnetic fields in galaxies and discuss the observational basis for such results in terms of rotation measure analysis. Next, we discuss nonlinear theory, the role of magnetic helicity conservation and magnetic helicity fluxes. This leads to the possibility that galactic magnetic fields may be bi-helical, with opposite signs of helicity and large and small length scales. We discuss their observational signatures and close by discussing the possibilities of explaining the origin of primordial magnetic fields.Comment: 28 pages, 15 figure, to appear in Lecture Notes in Physics "Magnetic fields in diffuse media", Eds. E. de Gouveia Dal Pino and A. Lazaria

    Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970–2016: a systematic analysis for the Global Burden of Disease Study 2016

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    BACKGROUND: Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016. METHODS: We have evaluated how well civil registration systems captured deaths using a set of demographic methods called death distribution methods for adults and from consideration of survey and census data for children younger than 5 years. We generated an overall assessment of completeness of registration of deaths by dividing registered deaths in each location-year by our estimate of all-age deaths generated from our overall estimation process. For 163 locations, including subnational units in countries with a population greater than 200 million with complete vital registration (VR) systems, our estimates were largely driven by the observed data, with corrections for small fluctuations in numbers and estimation for recent years where there were lags in data reporting (lags were variable by location, generally between 1 year and 6 years). For other locations, we took advantage of different data sources available to measure under-5 mortality rates (U5MR) using complete birth histories, summary birth histories, and incomplete VR with adjustments; we measured adult mortality rate (the probability of death in individuals aged 15-60 years) using adjusted incomplete VR, sibling histories, and household death recall. We used the U5MR and adult mortality rate, together with crude death rate due to HIV in the GBD model life table system, to estimate age-specific and sex-specific death rates for each location-year. Using various international databases, we identified fatal discontinuities, which we defined as increases in the death rate of more than one death per million, resulting from conflict and terrorism, natural disasters, major transport or technological accidents, and a subset of epidemic infectious diseases; these were added to estimates in the relevant years. In 47 countries with an identified peak adult prevalence for HIV/AIDS of more than 0·5% and where VR systems were less than 65% complete, we informed our estimates of age-sex-specific mortality using the Estimation and Projection Package (EPP)-Spectrum model fitted to national HIV/AIDS prevalence surveys and antenatal clinic serosurveillance systems. We estimated stillbirths, early neonatal, late neonatal, and childhood mortality using both survey and VR data in spatiotemporal Gaussian process regression models. We estimated abridged life tables for all location-years using age-specific death rates. We grouped locations into development quintiles based on the Socio-demographic Index (SDI) and analysed mortality trends by quintile. Using spline regression, we estimated the expected mortality rate for each age-sex group as a function of SDI. We identified countries with higher life expectancy than expected by comparing observed life expectancy to anticipated life expectancy on the basis of development status alone. FINDINGS: Completeness in the registration of deaths increased from 28% in 1970 to a peak of 45% in 2013; completeness was lower after 2013 because of lags in reporting. Total deaths in children younger than 5 years decreased from 1970 to 2016, and slower decreases occurred at ages 5-24 years. By contrast, numbers of adult deaths increased in each 5-year age bracket above the age of 25 years. The distribution of annualised rates of change in age-specific mortality rate differed over the period 2000 to 2016 compared with earlier decades: increasing annualised rates of change were less frequent, although rising annualised rates of change still occurred in some locations, particularly for adolescent and younger adult age groups. Rates of stillbirths and under-5 mortality both decreased globally from 1970. Evidence for global convergence of death rates was mixed; although the absolute difference between age-standardised death rates narrowed between countries at the lowest and highest levels of SDI, the ratio of these death rates-a measure of relative inequality-increased slightly. There was a strong shift between 1970 and 2016 toward higher life expectancy, most noticeably at higher levels of SDI. Among countries with populations greater than 1 million in 2016, life expectancy at birth was highest for women in Japan, at 86·9 years (95% UI 86·7-87·2), and for men in Singapore, at 81·3 years (78·8-83·7) in 2016. Male life expectancy was generally lower than female life expectancy between 1970 and 2016, an

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Global Retinoblastoma Presentation and Analysis by National Income Level

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    Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4) were female. Most patients (n = 3685 84.7%) were from low-and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 62.8%), followed by strabismus (n = 429 10.2%) and proptosis (n = 309 7.4%). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 95% CI, 12.94-24.80, and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 95% CI, 4.30-7.68). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs. © 2020 American Medical Association. All rights reserved

    Periumbilical ultrasonic-guided saline infusion technique (PUGSI): A step for safer laparoscopy in high risk patients for adhesions

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    Objective: To validate the technique of PUGSI in high risk patients for adhesions during laparoscopy. Design: Prospective study on PUGSI to predict obliterated subumbilical adhesions. Setting: El-Shatby Maternity Hospital, Alexandria University. Patients: Sixty women with risk factors for intraabdominal adhesions. Interventions: Preoperative examination with PUGSI. Results: The prevalence of obliterated subumbilical adhesions was 26.7%. Abnormal PUGSI was detected among 18 patients, of these, 15 patients were diagnosed at the time of laparoscopy to have obliterated subumbilical adhesions (9 patients with omental and 6 patients with bowel adhesions). PUGSI had a diagnostic accuracy of 93.3%, a sensitivity of 93.8%, a specificity of 93.2%, a positive predictive value (PPV) of 83.3% and a negative predictive value (NPV) of 97.6%. Conclusion: PUGSI can accurately predict obliterated subumbilical adhesions prior to laparoscopy in patients at high risk of visceral injury. Widespread application of this technique may decrease trocar-related injuries during laparoscopic access

    Diabetes care in Qatar: a survey of pharmacists’ activities, attitudes and knowledge

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    Background Diabetes mellitus is recognized as a major public health issue and is one of the top ten causes of death in Qatar. Objective To describe the activities, and attitudes of Qatar pharmacists toward diabetes, to measure their diabetes knowledge and to assess their perceived barriers for diabetes care. Setting Community and ambulatory pharmacies in Qatar. Method Study objectives were addressed in a cross sectional survey of community and ambulatory pharmacists in Qatar. A phone call explaining the study was made to all community and ambulatory pharmacists in Qatar. Consenting pharmacists anonymously completed the survey either online or as paper. Main outcome measure Diabetes related activities, knowledge, attitudes and perceived barriers. Results Over 7 months, 126 surveys were collected (28% response rate). The majority of pharmacists always or often counselled patients on the appropriate time to take each medication and on medication side effects (90%, n = 100/111 and 73%, n = 81/111 respectively). Yet around 50% always or often provided education on the importance of screening for nephropathy (n = 59/112) and retinopathy (n = 58/109). In addition, 41% always or often provided education about the importance of immunization (n = 45/111) and 45% always or often provided therapy recommendations to physicians (n = 49/111). Using Diabetes Attitude Scale-3, most respondents had positive attitudes toward the need for special training, psychosocial impact of diabetes, and patient autonomy. Around 25% (n = 32/126) scored less than 6 out of 10 on the diabetes related knowledge test. The top three barriers for providing diabetes services were lack of time (53%, n = 67/126) shortage of personnel (42%, n = 53/126) and lack of private counseling area (42%, n = 53/126). Conclusion Qatar pharmacists mainly provide basic services for diabetic patients. They have an average diabetes related knowledge. Yet overall, they have positive attitudes toward diabetes, which is a vital component of any successful diabetes care service. © 2017, Springer International Publishing AG, part of Springer Nature.Funding This publication was made possible by a UREP (Undergraduate Research Experience Program (UREP) award [UREP 10 - 032 - 3 -008] from the Qatar National Research Fund (a member of The Qatar Foundation). The statements made herein are solely the responsibility of the author[s].Scopu

    Adsorption of Ethoxylated Sulfonates on Limestone

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    Stastic adsorption experiments have been conducted to investigate the adsorption and precipitation behavior of various ethoxylated sulfonates from Saudi Arabian limestone samples under high-salinity (20%) and high temperature conditions (90°C). The effect of parameters such as salinity, pH, temperature, ethoxylation number, oil and alcohol addition has been investigated. Mechanisms governing surfactant adsorption on limestone are elucidated. A surfactant formulation has been designed to achieve minimum surfactant loss for Saudi Arabian limestone reservoirs

    Detection of Avian Leukosis Virus Subgroup J in Egyptian Ducks and Chicken Using Molecular and Histopathological Approach and Allocation of Genetic Mutations and Recombination Events in the Envelope Protein Gene gp85

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    Avian leukosis virus (ALV) is an oncogenic contagious virus infecting different avian species. This study aims to molecularly detect the circulating strains of ALV in various chicken and duck farms at different Egyptian governorates. Freshly dead birds were exposed for postmortem examination (PM) then samples were processed for histopathological examination as well as molecular detection of ALV using qRT-PCR and sequence analysis of the envelope glycoprotein gene (gp85) surface protein antigen with detection of recombination events that might be found between the detected strains. PM revealed the existence of diffuse enlargement of most internal organs, and in some cases, nodular enlargement was observed. Histopathological investigation showed myeloid cells infiltration of eosinophilic granular cytoplasm in the examined tissues. Five molecularly positive samples were sequenced and submitted in the GenBank with accession numbers MZ614719, MZ614720, MZ614721, MZ614722, and MZ614723. The phylogenetic tree construction based on the sequenced gp85 gene revealed that all Egyptian isolates were nearly arranged in a single branch despite the year of collection and were phylogenetically distant from other sequences. In general, studies concerning the genetic diversity of gp85, and the recombination events concluded that the ALV-J virus is a wide host range involving both chicken and ducks. Because ALV causes serious financial problems to threaten poultry production and neither vaccines nor treatment tools are now available for ALV prevention and control, periodical molecular monitoring with whole genome sequence and analysis for the circulating strains with ethical eradication of the positive birds are recommended to overcome such a problem
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