61 research outputs found
A 28/38 GHz tuned reconfigurable antenna for 5G mobile communications
In this paper, a compact tuned reconfigurable microstrip antenna for fifth generation (5G) mobile communications is designed to operate at 28 GHz or 38 GHz or both frequencies. The proposed antenna can be reconfigured by using a group of PIN diodes switches across a slit in the upper traditional patch antenna or through the ground plane side. The tuning between the 28 GHz and 38GHz frequency bands can be achieved through ON/OFF states of the PIN diodes switches. The tuned reconfigurable antenna is simulated using CST software package and then fabricated and measured. The simulated and measured results show good agreement with a little deviation. The proposed tuned antenna is small in size with 18×11.25 mm2 overall area
Herbal Medicine for Cardiovascular Diseases: Efficacy, Mechanisms, and Safety
Cardiovascular diseases (CVDs) are a significant health burden with an ever-increasing
prevalence. They remain the leading causes of morbidity and mortality worldwide. The use
of medicinal herbs continues to be an alternative treatment approach for several diseases
including CVDs. Currently, there is an unprecedented drive for the use of herbal
preparations in modern medicinal systems. This drive is powered by several aspects,
prime among which are their cost-effective therapeutic promise compared to standard
modern therapies and the general belief that they are safe. Nonetheless, the claimed
safety of herbal preparations yet remains to be properly tested. Consequently, public
awareness should be raised regarding medicinal herbs safety, toxicity, potentially lifethreatening
adverse effects, and possible herb–drug interactions. Over the years,
laboratory data have shown that medicinal herbs may have therapeutic value in CVDs
as they can interfere with several CVD risk factors. Accordingly, there have been many
attempts to move studies on medicinal herbs from the bench to the bedside, in order to
effectively employ herbs in CVD treatments. In this review, we introduce CVDs and their
risk factors. Then we overview the use of herbs for disease treatment in general and CVDs
in particular. Further, data on the ethnopharmacological therapeutic potentials and
medicinal properties against CVDs of four widely used plants, namely Ginseng, Ginkgo
biloba, Ganoderma lucidum, and Gynostemma pentaphyllum, are gathered and reviewed.
In particular, the employment of these four plants in the context of CVDs, such as
myocardial infarction, hypertension, peripheral vascular diseases, coronary heart disease,
cardiomyopathies, and dyslipidemias has been reviewed, analyzed, and critically
discussed. We also endeavor to document the recent studies aimed to dissect the
cellular and molecular cardio-protective mechanisms of the four plants, using recently
reported in vitro and in vivo studies. Finally, we reviewed and reported the results of the recent clinical trials that have been conducted using these four medicinal herbs with
special emphasis on their efficacy, safety, and toxicity.This work has been made possible thanks to grants (Ager S.O.S.) and (fondo di Ateneo per la ricerca 2019) to GP and Qatar University grant (IRCC-2019-007) to GN and GP
Biomaterials in Traumatic Brain Injury: Perspectives and Challenges
Traumatic brain injury (TBI) is a leading cause of mortality and long-term impairment globally. TBI has a dynamic pathology, encompassing a variety of metabolic and molecular events that occur in two phases: primary and secondary. A forceful external blow to the brain initiates the primary phase, followed by a secondary phase that involves the release of calcium ions (Ca2+) and the initiation of a cascade of inflammatory processes, including mitochondrial dysfunction, a rise in oxidative stress, activation of glial cells, and damage to the blood–brain barrier (BBB), resulting in paracellular leakage. Currently, there are no FDA-approved drugs for TBI, but existing approaches rely on delivering micro- and macromolecular treatments, which are constrained by the BBB, poor retention, off-target toxicity, and the complex pathology of TBI. Therefore, there is a demand for innovative and alternative therapeutics with effective delivery tactics for the diagnosis and treatment of TBI. Tissue engineering, which includes the use of biomaterials, is one such alternative approach. Biomaterials, such as hydrogels, including self-assembling peptides and electrospun nanofibers, can be used alone or in combination with neuronal stem cells to induce neurite outgrowth, the differentiation of human neural stem cells, and nerve gap bridging in TBI. This review examines the inclusion of biomaterials as potential treatments for TBI, including their types, synthesis, and mechanisms of action. This review also discusses the challenges faced by the use of biomaterials in TBI, including the development of biodegradable, biocompatible, and mechanically flexible biomaterials and, if combined with stem cells, the survival rate of the transplanted stem cells. A better understanding of the mechanisms and drawbacks of these novel therapeutic approaches will help to guide the design of future TBI therapies
Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. 
Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. 
Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82  hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%]  of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%]  of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). 
Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
Glycomic and Glycoproteomic Techniques in Neurodegenerative Disorders and Neurotrauma: Towards Personalized Markers
The proteome represents all the proteins expressed by a genome, a cell, a tissue, or an organism at any given time under defined physiological or pathological circumstances. Proteomic analysis has provided unparalleled opportunities for the discovery of expression patterns of proteins in a biological system, yielding precise and inclusive data about the system. Advances in the proteomics field opened the door to wider knowledge of the mechanisms underlying various post-translational modifications (PTMs) of proteins, including glycosylation. As of yet, the role of most of these PTMs remains unidentified. In this state-of-the-art review, we present a synopsis of glycosylation processes and the pathophysiological conditions that might ensue secondary to glycosylation shortcomings. The dynamics of protein glycosylation, a crucial mechanism that allows gene and pathway regulation, is described. We also explain how-at a biomolecular level-mutations in glycosylation-related genes may lead to neuropsychiatric manifestations and neurodegenerative disorders. We then analyze the shortcomings of glycoproteomic studies, putting into perspective their downfalls and the different advanced enrichment techniques that emanated to overcome some of these challenges. Furthermore, we summarize studies tackling the association between glycosylation and neuropsychiatric disorders and explore glycoproteomic changes in neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington disease, multiple sclerosis, and amyotrophic lateral sclerosis. We finally conclude with the role of glycomics in the area of traumatic brain injury (TBI) and provide perspectives on the clinical application of glycoproteomics as potential diagnostic tools and their application in personalized medicine
Drug Repurposing in Neurological Disorders: Implications for Neurotherapy in Traumatic Brain Injury
Traumatic brain injury (TBI) remains a significant leading cause of death and disability among adults and children globally. To date, there are no Food and Drug Administration–approved drugs that can substantially attenuate the sequelae of TBI. The innumerable challenges faced by the conventional de novo discovery of new pharmacological agents led to the emergence of alternative paradigm, which is drug repurposing. Repurposing of existing drugs with well-characterized mechanisms of action and human safety profiles is believed to be a promising strategy for novel drug use. Compared to the conventional discovery pathways, drug repurposing is less costly, relatively rapid, and poses minimal risk of the adverse outcomes to study on participants. In recent years, drug repurposing has covered a wide range of neurodegenerative diseases and neurological disorders including brain injury. This review highlights the advances in drug repurposing and presents some of the promising candidate drugs for potential TBI treatment along with their possible mechanisms of neuroprotection. Edaravone, glyburide, ceftriaxone, levetiracetam, and progesterone have been selected due to their potential role as putative TBI neurotherapeutic agents. These drugs are Food and Drug Administration–approved for purposes other than brain injuries; however, preclinical and clinical studies have shown their efficacy in ameliorating the various detrimental outcomes of TBI. © The Author(s) 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
Assessment of diagnostic and prognostic laboratory biomarkers in severe COVID-19 patients admitted to intensive care unit
Coronavirus disease (COVID-19) is a global pandemic. In the first two years of the pandemic, nearly 15 million people died worldwide. Accurate and rapid laboratory diagnosis of COVID-19 infection is one of the milestones of pandemic control. Therefore, this study aimed to compare the diagnostic and prognostic accuracy of mainly used laboratory biomarkers (CRP, ferritin, IL-6, D-dimer, procalcitonin, and LDH) in the sera of severe COVID-19 Egyptian patients, to assess the most appropriate biomarker used in severe COVID-19 patients. A total of 120 COVID-19 patients and 50 normal controls were enrolled into our study. Demographic data, hospitalization time, medical history, oxygen saturation, respiratory rate, oxygen supply, laboratory findings and thorax tomography of the patients were obtained from the hospital electronic information system retrospectively. Our results revealed that the serum levels of CRP, ferritin, IL-6, D-dimer, PCT and LDH were highly significantly increased in severe COVID-19 patients as compared to normal controls (p<0.001), and in non-survivors as compared to survivors (p<0.001). By using ROC curve analysis, IL-6 appeared to be the most sensitive and specific marker with 80.9% sensitivity and 84.9% specificity; followed by LDH with 85.1% sensitivity and 82.8% specificity in the prediction of death. In conclusion CRP and IL-6 could be the most appropriate biomarkers in the diagnosis of severe COVID-19 disease, while IL-6 and LDH may be good predictors of mortality between severe COVID-19 patients.</jats:p
A Reconfigurable Notched Band Monopole Antenna for C-Band Applications
In this paper, a wideband monopole antenna with reconfigurable frequency notch through wireless local area network (WLAN) (5.15-5.35GHz and 5.725-5.825GHz) or future wireless fidelity 6GHz (Wi-Fi-6E) (5.925-7.125GHz) band for C-band applications is presented. The conventional/basic monopole antenna consists of four-leaf clover antenna structure with cascaded feeder and Defected Ground Structure (DGS). The basic antenna is designed and then simulated using Computer Simulation Technology (CST) and High-Frequency Structure Simulator (HFSS) readymade software programs. The antenna covering an operational bandwidth extends from 4.2GHz to 9.2GHz while the gain is around 4.0dBi. Two simple resonator conductors are added near the thin feeder of antenna to realize the notched frequency. The rejected frequency within WLAN or Wi-Fi 6E bands is controlled by the resonator conductor lengths, so Positive-Intrinsic-Negative (PIN) diodes switches are inserted to achieve the required length for each rejected band. Finally, each of the basic antenna and the proposed notched antenna are fabricated and measured. The measurement results are in good agreements with the simulated results of CST and HFSS, providing good antenna performance and sharp notches with good rejection values.</jats:p
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