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1.
BMJ Paediatr Open ; 8(1)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844386

RESUMO

BACKGROUND: Early-onset neonatal sepsis (EONS) remains an important disease entity due to very serious adverse outcomes if left untreated. Lack of diagnostic tools in identifying healthy from diseased neonates, and clinicians' fear of the missing positive-culture sepsis babies, or babies with clinical sepsis have led to overtreating and unnecessary antibiotic exposure. Kaiser Permanente EONS risk calculator is an internally validated tool that can predict EONS. This sepsis risk calculator (SRC) classifies neonates into three subgroups: (1) ill-appearing, (2) equivocal and (3) well-appearing. We propose a modification to this tool that aims to use it solely for well-appearing babies. This modification represents a more conservative approach to decrease antibiotic exposure and offers an alternative for those hesitant to fully implement this tool. METHODS: This is a dual-centre retrospective study where data were extracted from the electronic medical records. Our primary outcome was to validate the modified use of the SRC with a two-by-two table. Specificity, negative predictive value and expected antibiotic reduction were used to evaluate the tool's feasibility. RESULT: Among 770 babies suspected of EONS, the feasibility of the modified use was tested. The expected antibiotic exposure reduction rate on the modification was 40.4% overall. The proposed modification resulted in a specificity and negative predictive value of 99.28% (95% CI: 97.92% to 99.85%) and 99.5% (95% CI: 99% to 99.8%), respectively. CONCLUSION: The modified use of the sepsis risk calculator has shown that it can safely reduce antibiotic exposure in well-appearing babies. The modified use is used as a 'rule out' test that can identify very low risk of EONS babies, and safely minimise antibiotic exposure. Further prospective studies are needed to examine the efficacy of this use, and quality improvement projects are required to evaluate its applicability in different clinical settings.


Assuntos
Antibacterianos , Sepse Neonatal , Humanos , Estudos Retrospectivos , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Recém-Nascido , Medição de Risco , Sepse Neonatal/diagnóstico , Sepse Neonatal/prevenção & controle , Feminino , Masculino
2.
Artigo em Inglês | MEDLINE | ID: mdl-38876370

RESUMO

OBJECTIVE: To compare and evaluate early and midterm outcomes of a "no cross" novel approach with short tip vs. standard tip introducer systems for all distal components to prevent target vessel bridging stent kink or collapse during fenestrated endovascular aortic repair (FEVAR). METHODS: A retrospective analysis was conducted on all patients who underwent FEVAR at a tertiary referral centre between October 2016 and July 2022. The inclusion criterion was the use of renal artery fenestrations. Patients who had chronic dissections were included. Endpoints were analysed in two groups comprising the "no cross" group and the standard group, with all cases being consecutive in their respective groups. Cone beam computed tomography was used intra-operatively in all cases, and post-operative compute tomography angiograms and re-interventions were reviewed. Primary endpoints included technical success, intra-operative adjunctive procedures, adverse events related to the fenestration, and re-interventions, while secondary endpoints were secondary interventions and overall mortality. RESULTS: A total of 70 patients (35 in each group) were enrolled in the study, with 64 (91%) having juxta-renal aneurysms. There were no differences in demographics, cardiovascular risk factors, or aneurysm characteristics between the two groups. The "no cross" group demonstrated a significantly higher technical success rate (100% in all cases) compared with the standard group (29 cases, 83%; p = .010). Additionally, there were statistically significantly fewer intra-operative adjunctive procedures required in the "no cross" group (1.5% of fenestrations) compared with the standard group (8.2% of fenestrations) (p = .013). Overall median follow up was 32 months (interquartile range 22, 62 months). CONCLUSION: Implementation of a novel "no cross" concept during FEVAR, utilising a short dilator introducer tip on the distal bifurcated component and iliac extensions, significantly reduces intra-operative fenestration related adverse events and enhances technical success. Further studies with larger patient populations and longer follow up are needed to confirm these findings.

3.
BMC Med Educ ; 24(1): 35, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191396

RESUMO

BACKGROUND: Postgraduate pediatric dental residents' competency, to perform dental rehabilitation procedures under General anesthesia (GA), at different levels of training is challenging for operation time control. An adequate operation time (OT) for children decreases morbidity risk and improves hospital time utilization efficiency. The aim of the study is to assess the effect of pediatric dental resident training level on OT for pediatric dental rehabilitation procedures under GA at King Abdulaziz Medical City (KAMC). METHODS: A cross-sectional study included pediatric dental rehabilitation performed under GA by pediatric dental residents at (KAMC) -Jeddah from October/2015 to September/2022. The primary outcome was OT, and the predictive variable was resident training levels. A linear regression analysis was used to compare OT between procedures performed by junior (years 1-2) or senior (years 3-4) trainees, adjusting for patient and operative factors. RESULTS: One thousand seven pediatric dental rehabilitation cases were performed under GA by junior (13) and senior (31) residents. The univariant analysis indicated that OT for senior residents was significantly longer (13 min) than for junior residents. However, the linear regression analysis showed that senior residents had a significantly shorter OT when considering the more dental procedures performed per case under GA than junior residents. Senior residents took significantly more radiographs and performed more primary pulp therapies and multi-surface anterior colored restorations under GA than junior residents. CONCLUSIONS: The OT for pediatric dental rehabilitation procedures under GA is associated with resident training level. The total OT was significantly longer based on procedure number, type, and resident level. The study indicated that senior residents could manage more complex cases in a shorter time. The finding emphasizes the importance of assigning GA cases to residents based on their level and the case's complexity. Additionally, it helps standardize the resident privileges under GA and understand the impact of residency training on hospital efficiency.


Assuntos
Internato e Residência , Humanos , Criança , Estudos Transversais , Escolaridade , Hospitais , Modelos Lineares
4.
Children (Basel) ; 10(4)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37189894

RESUMO

Bronchiolitis is a leading cause of hospitalization worldwide for children aged ≤2 years. Few studies have compared general ward and pediatric intensive care unit (PICU) admissions, particularly in Saudi Arabia. This retrospective cohort study aimed to compare the demographic and clinical characteristics of children with bronchiolitis admitted to the general ward with those admitted to the PICU. Children (≤6 years) previously diagnosed with bronchiolitis and admitted to the PICU or general ward at a tertiary center in Saudi Arabia between May 2016 and May 2021 were included. Multiplex polymerase chain reaction was used to identify respiratory viruses. Of the 417 patients enrolled, 67 (16.06%) were admitted to the PICU. The PICU group was younger (median, 2 months; interquartile range [IQR], 1-5 months) vs. (6 months; IQR, 2.65-13.25 months). There was a dramatic reduction in bronchiolitis admissions during the COVID-19 pandemic. The most common causative virus was respiratory syncytial virus (RSV) (54.9%). In the multivariate regression analysis, hypoxia, hyperinflation on X-ray, and non-RSV bronchiolitis were independently associated with PICU admission. However, a higher chronological age and cough were protective. Children with Down syndrome, immunodeficiency, or neuromuscular disorders, and intermediate preterm infants (29-33 weeks of gestation) are at a high risk of PICU admission (adjusted odds ratio: 2.4, 7.1, 2.9, and 2.9; p = 0.037, 0.046, 0.033, and 0.029, respectively). Bronchiolitis is still one of the leading causes of PICU admission. Particular attention should be paid to preventive measures, especially in the post-COVID-19 era, targeting high-risk groups.

6.
Nanotechnology ; 33(22)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35172287

RESUMO

Chemical vapor deposition (CVD)-grown monolayer (ML) molybdenum disulfide (MoS2) is a promising material for next-generation integrated electronic systems due to its capability of high-throughput synthesis and compatibility with wafer-scale fabrication. Several studies have described the importance of Schottky barriers in analyzing the transport properties and electrical characteristics of MoS2field-effect-transistors (FETs) with metal contacts. However, the analysis is typically limited to single devices constructed from exfoliated flakes and should be verified for large-area fabrication methods. In this paper, CVD-grown ML MoS2was utilized to fabricate large-area (1 cm × 1 cm) FET arrays. Two different types of metal contacts (i.e. Cr/Au and Ti/Au) were used to analyze the temperature-dependent electrical characteristics of ML MoS2FETs and their corresponding Schottky barrier characteristics. Statistical analysis provides new insight about the properties of metal contacts on CVD-grown MoS2compared to exfoliated samples. Reduced Schottky barrier heights (SBH) are obtained compared to exfoliated flakes, attributed to a defect-induced enhancement in metallization of CVD-grown samples. Moreover, the dependence of SBH on metal work function indicates a reduction in Fermi level pinning compared to exfoliated flakes, moving towards the Schottky-Mott limit. Optical characterization reveals higher defect concentrations in CVD-grown samples supporting a defect-induced metallization enhancement effect consistent with the electrical SBH experiments.

7.
Adv Mater ; 32(33): e2002401, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32627918

RESUMO

Newly discovered 2D Janus transition metal dichalcogenides layers have gained much attention from a theory perspective owing to their unique atomic structure and exotic materials properties, but little to no experimental data are available on these materials. Here, experimental and theoretical studies establish the vibrational and optical behavior of 2D Janus S-W-Se and S-Mo-Se monolayers under high pressures for the first time. Chemical vapor deposition (CVD)-grown classical transition metal dichalcogenides (TMD) monolayers are first transferred onto van der Waals (vdW) mica substrates and converted to 2D Janus sheets by surface plasma technique, and then integrated into a 500 µm size diamond anvil cell for high-pressure studies. The results show that 2D Janus layers do not undergo phase transition up to 15 GPa, and in this pressure regime, their vibrational modes exhibit a nonmonotonic response to the applied pressures (dω/dP). Interestingly, these 2D Janus monolayers exhibit unique blueshift in photoluminescence (PL) upon compression, which is in contrast to many other traditional semiconductor materials. Overall theoretical simulations offer in-depth insights and reveal that the overall optical response is a result of competition between the ab-plane (blueshift) and c-axis (redshift) compression. The overall findings shed the very first light on how 2D Janus monolayers respond under extreme pressures and expand the fundamental understanding of these materials.

8.
Pediatr Hematol Oncol ; 37(7): 599-609, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32459595

RESUMO

Many patients with sickle cell disease (SCD) need surgical management during their lifetime. The best approach for preoperative transfusion in SCD is still to be determined. In this single-center retrospective study, we included HBSS/HBS-Beta0-thalassemia patients younger than 16 years of age who underwent surgery between January 2008 and July 2019. Preoperative transfusion assignment (PTA) was based on SCD severity and surgical risk. Patients were assigned to no transfusion, simple transfusion, or exchange transfusion. A total of 284 patients were identified and 66 (23%) underwent 78 procedures. Mean age at the time of procedure was 8 (5-11) years, mean baseline hemoglobin was 8.5 (7.8-9.3) g/dl, and mean hemoglobin F was 18.4 ± 8.2%. SCD severity was low-risk in 57 (73%) and high-risk in 21 (27%) patients. Surgical risk was low-risk in 20 (25.6%) and medium-risk in 58 (74.4%) procedures. PTA was no transfusion in 17 (22%), simple transfusion in 40 (51%), and exchange transfusion in 21 (27%) procedures. Postoperative complications occurred in five (6.4%) of procedures only in the simple transfusion group (three acute chest syndrome, one hemolytic anemia, one pain crisis) undergoing medium-risk surgery. Preoperative risk-based transfusion assignment is feasible. Despite a high baseline hemoglobin level in the no transfusion group, none of the patients developed postoperative complications. It is possible that the high baseline hemoglobin F phenotype was protective and indicates the need to study the risk/benefit of interventions used in this phenotype.


Assuntos
Anemia Falciforme/terapia , Transfusão de Sangue/métodos , Cuidados Pré-Operatórios/métodos , Anemia Falciforme/cirurgia , Criança , Pré-Escolar , Feminino , Hemoglobina Fetal/análise , Hemoglobinas/análise , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Arábia Saudita , Talassemia/cirurgia , Talassemia/terapia
9.
J Biochem Mol Toxicol ; 31(10)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28621814

RESUMO

Zebrafish has in recent years emerged as a popular vertebrate model for use in pharmacological and toxicological studies. While there have been sporadic studies on the zebrafish glutathione S-transferases (GSTs), the zebrafish GST gene superfamily still awaits to be fully elucidated. We report here the identification of 15 zebrafish cytosolic GST genes in NCBI GenBank database and the expression, purification, and enzymatic characterization of the zebrafish cytosolic GST Pi-1 (GSTP1). The cDNA encoding the zebrafish GSTP1 was cloned from a 3-month-old female zebrafish, expressed in Eschelichia coli host cells, and purified. Purified GSTP1 displayed glutathione-conjugating activity toward 1-chloro-2,4-dinitrobenzene as a representative substrate. The enzymatic characteristics of the zebrafish GSTP1, including pH-dependency, effects of metal cations, and kinetic parameters, were studied. Moreover, the expression of zebrafish GSTP1 at different developmental stages during embryogenesis, throughout larval development, onto maturity was examined.


Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Glutationa S-Transferase pi , Proteínas de Peixe-Zebra , Peixe-Zebra/metabolismo , Animais , Dinitroclorobenzeno/química , Feminino , Glutationa S-Transferase pi/biossíntese , Glutationa S-Transferase pi/química , Glutationa S-Transferase pi/genética , Especificidade por Substrato , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/biossíntese , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética
10.
Breed Sci ; 63(5): 450-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24757384

RESUMO

Adaptation of wheat (Triticum aestivum L.) to high temperatures could be improved by introducing alien genes from wild relatives. We evaluated the responses of wheat-Leymus racemosus chromosome introgression lines to high temperature to determine their potentiality for developing improved wheat cultivars. Introgression lines and their parent Chinese Spring were evaluated in a growth chamber at the seedling stage and in the field at the reproductive stage in two heat-stressed environments in Sudan. Optimum and late planting were used to ensure exposure of the plants to heat stress at the reproductive stage. The results revealed the impact of several Leymus chromosomes in improving wheat adaptation and tolerance to heat. Three lines possessed enhanced adaptation, whereas two showed high heat tolerance. Two addition lines showed a large number of kernels per spike, while one possessed high yield potential. Grain yield was correlated negatively with the heat susceptibility index, days to heading and maturity and positively with kernel number per spike and triphenyl tetrazolium chloride assay under late planting. The findings suggest that these genetic stocks could be used as a bridge to introduce the valuable Leymus traits into a superior wheat genetic background, thus helping maximize wheat yield in heat-stressed environments.

11.
Breed Sci ; 63(4): 407-16, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24399913

RESUMO

Aluminum (Al) toxicity is the key factor limiting wheat production in acid soils. Soil liming has been used widely to increase the soil pH, but due to its high cost, breeding tolerant cultivars is more cost-effective mean to mitigate the problem. Tolerant cultivars could be developed by traditional breeding, genetic transformation or introgression of genes from wild relatives. We used 30 wheat alien chromosome addition lines to identify new genetic resources to improve wheat tolerance to Al and to identify the chromosomes harboring the tolerance genes. We evaluated these lines and their wheat background Chinese Spring for Al tolerance in hydroponic culture at various Al concentrations. We also investigated Al uptake, oxidative stress and cell membrane integrity. The L. racemosus chromosomes A and E significantly enhanced the Al tolerance of the wheat in term of relative root growth. At the highest Al concentration tested (200 µM), line E had the greatest tolerance. The introgressed chromosomes did not affect Al uptake of the tolerant lines. We attribute the improved tolerance conferred by chromosome E to improved cell membrane integrity. Chromosome engineering with these two lines could produce Al-tolerant wheat cultivars.

12.
Biol Pharm Bull ; 35(12): 2180-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23207770

RESUMO

Ethyl sulfate, a minor and direct ethanol metabolite in adult human body, has been implicated as a biomarker for alcohol consumption and in utero exposure to ethanol. To understand better the physiological relevance of the sulfation of ethanol, it is important to clarify the cytosolic sulfotransferase (SULT) enzymes that are responsible for ethanol sulfation. The present study aimed to identify the major ethanol-sulfating human SULTs and to investigate the sulfation of ethanol under the metabolic setting. A systematic analysis revealed four ethanol-sulfating SULTs, SULT1A1, SULT1A2, SULT1A3, and SULT1C4, among the eleven human SULT enzymes previously prepared and purified. A metabolic labeling study demonstrated the generation and release of ethyl [(35)S]sulfate in a concentration-dependent manner by HepG2 human hepatoma cells labeled with [(35)S]sulfate in the presence of different concentrations of ethanol. Cytosol or S9 fractions of human lung, liver, and small intestine were examined to verify the presence of ethanol-sulfating activity in vivo. Of the three human organs, the small intestine displayed the highest activity.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Etanol/metabolismo , Intestino Delgado/enzimologia , Fígado/enzimologia , Pulmão/enzimologia , Sulfotransferases/metabolismo , Ésteres do Ácido Sulfúrico/metabolismo , Adulto , Biomarcadores/metabolismo , Citosol/metabolismo , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Coloração e Rotulagem
13.
Aquat Toxicol ; 112-113: 11-8, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22360938

RESUMO

By searching the GenBank database, we identified sequences encoding three new zebrafish cytosolic sulfotransferases (SULTs). These three new zebrafish SULTs, designated SULT1 ST9, SULT3 ST4, and SULT3 ST5, were cloned, expressed, purified, and characterized. SULT1 ST9 appeared to be mostly involved in the metabolism and detoxification of xenobiotics such as ß-naphthol, ß-naphthylamine, caffeic acid and gallic acid. SULT3 ST4 showed strong activity toward endogenous compounds such as dehydroepiandrosterone (DHEA), pregnenolone, and 17ß-estradiol. SULT3 ST5 showed weaker, but significant, activities toward endogenous compounds such as DHEA and corticosterone, as well as xenobiotics including mestranol, ß-naphthylamine, ß-naphthol, and butylated hydroxyl anisole (BHA). pH-dependency and kinetic constants of these three enzymes were determined with DHEA, ß-naphthol, and 17ß-estradiol as substrates. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to examine the expression of these three new zebrafish SULTs at different developmental stages during embryogenesis, through larval development, and on to maturity.


Assuntos
Sulfotransferases/genética , Sulfotransferases/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Análise por Conglomerados , Citosol/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Especificidade por Substrato , Sulfotransferases/química , Sulfotransferases/isolamento & purificação , Peixe-Zebra/classificação , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/isolamento & purificação
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