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1.
ACS Omega ; 9(17): 18827-18835, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38708248

RESUMO

Recent studies show that nanofillers greatly contribute to the increase in the mechanical and abrasive behaviors of the polymer composite. In the current study, epoxy composites were made by hand lay-up with the reinforcement of carbon fabric and titanium dioxide (TiO2) nanoparticles as secondary reinforcement in weight percentages of 0.5, 1.0, and 2.0. Hardness, tensile, and abrasive wear tests have been carried out for the fabricated composites. The obtained results confirm that as the percentage of filler addition increases, hardness of the carbon epoxy (CE) composite increases, and significant enhancement of 10.25% hardness is confirmed in 2 wt % nano TiO2-added CE composite. The CE composite filled with 2 wt % of TiO2 nanofiller shows 15.77 and 9.15% improvement of tensile strength and modulus, respectively, compared to unfilled CE composites. The abrasive wear volume exhibits a nearly linear increasing trend as the abrading distance increases. In addition, it is discovered that the abrasive wear volume is greater for higher applied loads. The inclusion of nano TiO2 reduced the wear loss in the CE composite for all abrading distances, regardless of the load, low or high. The scanning electron microscopy analysis of worn surfaces was carried out to analyze the contribution of the filler to improve the wear resistance.

2.
Spine Deform ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722532

RESUMO

PURPOSE: This study aims to conduct a systematic review of the literature comparing pre-operative, intraoperative, and post-operative characteristics between adolescent idiopathic scoliosis (AIS) and young adult idiopathic scoliosis (YAdIS) patients. METHODS: Following PRISMA guidelines, we conducted a search of the PubMed/Medline, EMBASE, and Cochrane Central databases to identify full-text articles in the English-language literature. Our inclusion criteria were studies that compared preoperative, intraoperative, and postoperative characteristics between AIS and YAdIS patients. We performed a meta-analysis reporting mean difference (MD) for continuous variables and Odds ratios (ORs) to assess differences in postoperative complications. RESULTS: Seven studies consisting of 1562 patients were included in the meta-analysis. The AIS group exhibited less intraoperative bleeding and shorter surgical procedures, with a mean difference between groups of 122.3 ml (95% CI 46.2-198.4, p = 0.002) and 28.7 min (95% CI 6.5-50.8, p = 0.01), respectively. Although the preoperative Cobb angle did not differ between groups (p = 0.65), patients with AIS achieved superior postoperative deformity correction, with a mean difference of 7.3% between groups, MD - 7.3 (95% CI - 9.7, - 4.8, p < 0.00001), and lower postoperative Cobb angles of the major curve, MD 4.2 (95% CI 3.1, 5.3, p < 0.00001). YAdIS patients were fused, on average, 0.2 more vertebral levels than AIS patients, MD 0.2 (95% CI 0.01, 0.5, p = 0.04). AIS patients experienced a significantly shorter length of stay after the surgical procedure, with an MD of 0.8 days (95% CI 0.1, 1.6, p = 0.02). No significant difference was found between groups in terms of complications (p = 0.19). CONCLUSIONS: YAdIS should be regarded as a distinct surgical entity, characterized by increased bleeding, longer surgical duration, greater deformity correction challenges, and the need for fusion of additional vertebral levels compared to AIS. Surgeons should be mindful of these differences and discuss them with patients and their families, especially in cases where the correction of the AIS deformity is delayed and there is a high risk of progression after skeletal maturity. Further research is needed to explore alternative surgical techniques and enhance outcomes for YAdIS patients.

3.
SAGE Open Med ; 12: 20503121241247458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711467

RESUMO

Objectives: Epilepsy is a neurological disorder affecting more than 50 million human lives of all ages, its social, physical and psychological implications is of huge concern. The current study and as a continuation of epilepsy knowledge assessment projects conducted by our research team is aimed to assess the knowledge of healthcare workers regarding epilepsy first aid in Saudi Arabia. Methods: A cross-sectional questionnaire-based study was carried out from 2020 to 2021. Results: During the study period, 272 healthcare workers were recruited; participants were males and females from different nationalities in various Saudi Arabian cities, possess diverse qualifications, and belong to several healthcare-related professions. The question, "Did you witness an epileptic seizure"? was answered as "Yes" by 42% of participants, and in response to the question "If you know that this patient struggles during seizure attacks," 58% of respondents stated that they would not call an ambulance. Moreover, the question "Put something in his/her mouth to prevent tongue biting" was incorrectly answered as "Yes" by 42% of respondents, and the question "Try to catch him/her and stop his/her movement" in order to control the attack was answered "Yes" by 21% of respondents. Furthermore, almost 90% of healthcare participants do not know how to use the Vagus Nerve Stimulation device. The mean knowledge score among participants was 23.7; sex, as well as type of higher qualification obtained, was found to be significantly associated with the score of knowledge. Conclusion: Knowledge toward epilepsy and epilepsy first aid among healthcare workers in Saudi Arabia was found fragile. Further research is appreciated to support the current findings.

6.
Cell Mol Life Sci ; 81(1): 207, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709385

RESUMO

The co-localization of the lysosomal protease cathepsin B (CTSB) and the digestive zymogen trypsinogen is a prerequisite for the initiation of acute pancreatitis. However, the exact molecular mechanisms of co-localization are not fully understood. In this study, we investigated the role of lysosomes in the onset of acute pancreatitis by using two different experimental approaches. Using an acinar cell-specific genetic deletion of the ras-related protein Rab7, important for intracellular vesicle trafficking and fusion, we analyzed the subcellular distribution of lysosomal enzymes and the severity of pancreatitis in vivo and ex vivo. Lysosomal permeabilization was performed by the lysosomotropic agent Glycyl-L-phenylalanine 2-naphthylamide (GPN). Acinar cell-specific deletion of Rab7 increased endogenous CTSB activity and despite the lack of re-distribution of CTSB from lysosomes to the secretory vesicles, the activation of CTSB localized in the zymogen compartment still took place leading to trypsinogen activation and pancreatic injury. Disease severity was comparable to controls during the early phase but more severe at later time points. Similarly, GPN did not prevent CTSB activation inside the secretory compartment upon caerulein stimulation, while lysosomal CTSB shifted to the cytosol. Intracellular trypsinogen activation was maintained leading to acute pancreatitis similar to controls. Our results indicate that initiation of acute pancreatitis seems to be independent of the presence of lysosomes and that fusion of lysosomes and zymogen granules is dispensable for the disease onset. Intact lysosomes rather appear to have protective effects at later disease stages.


Assuntos
Catepsina B , Lisossomos , Pancreatite , Vesículas Secretórias , Proteínas rab de Ligação ao GTP , proteínas de unión al GTP Rab7 , Animais , Lisossomos/metabolismo , Pancreatite/metabolismo , Pancreatite/patologia , Pancreatite/genética , Catepsina B/metabolismo , Catepsina B/genética , Camundongos , Vesículas Secretórias/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , proteínas de unión al GTP Rab7/metabolismo , Doença Aguda , Células Acinares/metabolismo , Células Acinares/patologia , Tripsinogênio/metabolismo , Tripsinogênio/genética , Ceruletídeo , Precursores Enzimáticos/metabolismo , Precursores Enzimáticos/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout
7.
Cureus ; 16(4): e59211, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38807818

RESUMO

Introduction Laryngopharyngeal reflux (LPR) is a condition characterized by the backflow of gastric contents rising through the esophagus, affecting the aerodigestive tract and leading to throat symptoms such as hoarseness, chronic cough, and throat clearing. LPR is recognized as a separate condition from gastroesophageal reflux disease, despite the fact that they both involve the backflow of the stomach contents as their primary pathology. Our study aimed to evaluate the prevalence of LPR within the population of Saudi Arabia. Methods A cross-sectional study was conducted using an electronic questionnaire from August to November 2023, involving participants from all five regions of Saudi Arabia. A total of 1140 participants completed the questionnaire, which included the Reflux Symptom Index (RSI) to assess the prevalence of LPR. Results LPR was found to be prevalent in 31.2% of the study population, with the most common associated demographics being female gender (p = 0.032) and adults aged 36-45 years (p = 0.006). However, no significant relationship was observed based on region of residence or other demographic factors such as education level or occupation. Conclusion LPR has a high prevalence in the population of Saudi Arabia. Therefore, further research and awareness about this condition are warranted to better understand its impact, improve diagnosis, and develop appropriate management strategies.

8.
Open Vet J ; 14(4): 1029-1042, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38808298

RESUMO

Background: Postpartum ovarian dysfunction [ovarian cyst (OC) and persistent follicle (PF)] has been an important issue. Finding effective hormonal treatments to improve reproductive performance in dairy cows has become a necessity. Aim: Improve reproductive performance and ovarian activity in postpartum cows with specific customized treatment for OC and PFs. Methods: The study included 48 cows at 14 days P.P, which received two dosages of 500 µg IM cloprostenol, 14 days apart as presynchronization protocol. Ultrasound ovarian scans 14 days after the last injection for 4 weeks. The cows were divided into three groups according to ovarian status: OC (n = 14), PF (n = 12), and NE (n = 22). In the OC group, received 500 µg IM cloprostenol and 100 µg IM cystoriline, a second dose of cloprostenol 14 days later and a second dose of cystoriline 36 hours later, and AI after 24 hours (GnRH+ PG/PG/GnRH). In the PF group, was fitted with progesterone-releasing intravaginal device (PRID) for 9 days; the same day, they received 100 µg cystoreline then 500 µg cloprostenol 7 days later, after PRID removal AI 56 hours later (PRID + GnRH/PG). In the NE group, artificial insemination was implemented until 28 days depending on estrus detection. Results: The ovarian activity was greatly affected by the customized treatments, leading to enhanced follicular and luteal activity, particularly after the PGF2α injection. The OC and PF groups showed substantial estrus responses of 71.43% and 75.02%, respectively, during AI time. While the NE group had an ovulation rate of 54.5% and a pregnancy rate of 31.8%, the treatment groups showed marked improvements in reproductive performance. The ovulation rates in the OC and PF groups were 71.43% and 75% and the pregnancy rates at the 1st artificial insemination were 64.28% and 66.7%. Conclusion: Improving reproductive performance and minimizing the time to first service are possible advantages of early case-specific treatment for postpartum cows with OC and PFs.


Assuntos
Doenças dos Bovinos , Cloprostenol , Inseminação Artificial , Cistos Ovarianos , Período Pós-Parto , Animais , Feminino , Bovinos , Cistos Ovarianos/veterinária , Cloprostenol/administração & dosagem , Cloprostenol/farmacologia , Doenças dos Bovinos/terapia , Doenças dos Bovinos/tratamento farmacológico , Inseminação Artificial/veterinária , Gravidez , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Progesterona/administração & dosagem , Sincronização do Estro
9.
Int J Surg ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775499

RESUMO

BACKGROUND: Stem cell therapy offers promising benefits like modulating immune responses, reducing inflammation, and aiding liver regeneration. This umbrella review seeks to compile evidence from systematic reviews to assess the efficacy of stem cell therapy for improving liver function and survival rates in chronic liver disease patients. METHODS: We searched electronic databases up to February 15, 2024. The selection process focused on systematic reviews comparing stem cell therapy with standard care or a placebo. The primary outcomes evaluated were changes in liver enzymes, the MELD score, and survival rates. Nested Knowledge software was utilized for screening and data extraction. All statistical analyses were performed using R software, version 4.3. RESULTS: Our umbrella review included 28 systematic reviews. The meta-analysis showcased a notable improvement in survival rates with a pooled RR of 1.487 (95% CI: 1.281 to 1.727). In non-randomized studies, albumin levels exhibited an SMD of 0.786 (95% CI: 0.368 to 1.204), indicating positive therapeutic effects. For ALT, the meta-analysis revealed a decrease in levels with an SMD of -0.499 (95% CI: -0.834 to -0.164), and for AST, an overall SMD of -0.362 (95% CI: -0.659 to -0.066) was observed, suggesting hepatoprotective effects. No significant changes were observed in total bilirubin levels and MELD scores in RCTs. CONCLUSION: Stem cell therapy exhibits potential as a novel treatment for chronic liver diseases, as it has demonstrated improvements in survival rates and certain liver function markers. More high-quality RCTs are needed in the future to fully ascertain the efficacy of stem cell therapy in this patient population.

10.
Int J Impot Res ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778151

RESUMO

Semaglutide was approved in June 2021 for weight loss in non-diabetic, obese patients. While package inserts include sexual dysfunction as a side effect, no study has assessed the degree of this risk. The objective of our study is to assess the risk of developing erectile dysfunction after semaglutide is prescribed for weight loss in obese, non-diabetic men. The TriNetX Research database was used to identify men without a diagnosis of diabetes ages 18 to 50 with BMI > 30 who were prescribed semaglutide after June 1st, 2021. Men were excluded if they had a prior erectile dysfunction diagnosis, any phosphodiesterase-5 inhibitors prescription, intracavernosal injections, penile prosthesis placement, history of testosterone deficiency, testosterone prescription, pelvic radiation, radical prostatectomy, pulmonary hypertension, or were deceased. We further restricted our cohort to non-diabetic, obese men by excluding men with a prior diabetes mellitus diagnosis, a hemoglobin A1c > 6.5%, or having ever received insulin or metformin. Men were then stratified into cohorts of those that did and did not receive a semaglutide prescription. The primary outcome was the risk of new ED diagnosis and/or new prescription of phosphodiesterase type 5 inhibitors at least one month after prescription of semaglutide. The secondary outcome was risk of testosterone deficiency diagnosis. Risk was reported using risk ratios with 95% confidence intervals (95% CI). 3,094 non-diabetic, obese men ages 18-50 who received a prescription of semaglutide were identified and subsequently matched to an equal number cohort of non-diabetic, obese men who never received a prescription of semaglutide. After matching, average age at index prescription for non-diabetic, obese men was 37.8 ± 7.8 and average BMI at index prescription was 38.6 ± 5.6. Non-diabetic men prescribed semaglutide were significantly more likely to develop erectile dysfunction and/or were prescribed phosphodiesterase type 5 inhibitors (1.47% vs 0.32%; RR: 4.5; 95% CI [2.3, 9.0]) and testosterone deficiency (1.53% vs 0.80%; RR: 1.9; 95% CI [1.2, 3.1]) when compared to the control cohort of non-diabetic men who never received a semaglutide prescription.

11.
Psychosom Med ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38787545

RESUMO

OBJECTIVE: Acute exercise elicits various biobehavioral and psychological responses, but results are mixed with regard to the magnitude of exercise-induced affective reactions. This meta-analysis examines the magnitude of general mood state, anxiety, and depressive symptom responses to acute exercise while exploring exercise protocol characteristics and background health behaviors that may play a role in the affective response. METHODS: A total of 2,770 articles were identified from a MEDLINE/PubMed search and an additional 133 articles from reviews of reference sections. Studies had to have measured general mood before the acute exercise bout and within 30 minutes after exercise completion. Effect sizes were estimated using Hedges' g, with larger values indicating improvement in the outcome measure. RESULTS: A total of 103 studies were included presenting data from 4,671 participants. General mood state improved from pre-exercise to post-exercise (g = 0.336, 95%CI = 0.234,0.439). Anxiety (g = 0.497, 95%CI = 0.263,0.730) and depressive symptoms (g = 0.407, 95%CI = 0.249,0.564) also improved with exercise. There was substantial and statistically significant heterogeneity in each of these meta-analyses. This heterogeneity was not explained by differences in participants' health status. Meta-regression analyses with potential moderators (intensity of exercise, mode of exercise, usual physical activity level, or weight status of participants) also did not reduce the heterogeneity. CONCLUSION: This meta-analysis shows significantly improved general mood, decreased anxiety, and lower depressive symptoms in response to an acute bout of exercise. There was substantial heterogeneity in the magnitude of the effect sizes, indicating that additional research is needed to identify determinants of a positive affective response to acute exercise.

12.
PLoS One ; 19(5): e0303053, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776297

RESUMO

OBJECTIVE: To describe the protocol of a prospective study to test the validity of intermuscular coherence (IMC) as a diagnostic tool and biomarker of upper motor neuron degeneration in amyotrophic lateral sclerosis (ALS). METHODS: This is a multicenter, prospective study. IMC of muscle pairs in the upper and lower limbs is gathered in ∼650 subjects across three groups using surface electrodes and conventional electromyography (EMG) machines. The following subjects will be tested: 1) neurotypical controls; 2) patients with symptomatology suggestive for early ALS but not meeting probable or definite ALS by Awaji Criteria; 3) patients with a known ALS mimic. The recruitment period is between 3/31/2021 and 12/31/2025. Written consent will be sought from the subject or the subject's legally authorized representative during enrollment. RESULTS: The endpoints of this study include: 1) whether adding IMC to the Awaji ALS criteria improve its sensitivity in early ALS and can allow for diagnosis earlier; 2) constructing a database of IMC across different ages, genders, and ethnicities. SIGNIFICANCE: This study may validate a new inexpensive, painless, and widely available tool for the diagnosis of ALS.


Assuntos
Esclerose Lateral Amiotrófica , Biomarcadores , Eletromiografia , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/fisiopatologia , Humanos , Estudos Prospectivos , Eletromiografia/métodos , Biomarcadores/análise , Masculino , Feminino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Músculo Esquelético/patologia , Neurônios Motores/patologia , Idoso , Adulto
13.
Ann Med Surg (Lond) ; 86(5): 3066-3071, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38694386

RESUMO

Introduction and importance: Moyamoya disease (MMD) is a condition characterized by progressive narrowing of arteries in the brain and abnormal development of small collateral vessels. It is commonly found in East Asia but has never been reported in Palestine. Case presentation: A 2-year-old female, part of a twin born to non-consanguineous parents, presented with recurring seizures and developmental regression. The physical examination revealed signs of hypotonia, reflex abnormalities, and bilateral Babinski signs. Comprehensive laboratory tests and imaging investigations confirmed the diagnosis of MMD, marking this patient as the reported case in Palestine. Clinical discussion: The diagnostic criteria for this condition were revised in 2021 to focus on findings seen in angiography and magnetic resonance angiography (MRA) scans. MMD has not been curative so far, and the management is focused on preventing complications, sometimes with surgical revascularization, including its different approaches: direct, indirect, and a combination of both. Conclusion: This case highlights the importance of identifying MMD in regions where it is uncommon to be diagnosed. It emphasizes the need for diagnosis and appropriate intervention to reduce complications.

14.
Best Pract Res Clin Gastroenterol ; 69: 101912, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38749579

RESUMO

Endoscopic resection techniques have evolved over time, allowing effective and safe resection of the majority of pre-malignant and early cancerous lesions in the gastrointestinal tract. Bleeding is one of the most commonly encountered complications during endoscopic resection, which can interfere with the procedure and result in serious adverse events. Intraprocedural bleeding is relatively common during endoscopic resection and, in most cases, is a mild and self-limiting event. However, it can interfere with the completion of the resection and may result in negative patient-related outcomes in severe cases, including the need for hospitalization and blood transfusion as well as the requirement for radiological or surgical interventions. Appropriate management of intraprocedural bleeding can improve the safety and efficacy of endoscopic resection, and it can be readily achieved with the use of several endoscopic hemostatic tools. In this review, we discuss the recent advances in the approach to intraprocedural bleeding complicating endoscopic resection, with a focus on the various endoscopic hemostatic tools available to manage such events safely and effectively.


Assuntos
Hemorragia Gastrointestinal , Hemostase Endoscópica , Humanos , Hemostase Endoscópica/métodos , Hemostase Endoscópica/efeitos adversos , Hemostase Endoscópica/instrumentação , Hemorragia Gastrointestinal/cirurgia , Hemorragia Gastrointestinal/etiologia , Resultado do Tratamento , Endoscopia Gastrointestinal/efeitos adversos , Endoscopia Gastrointestinal/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Hemostáticos/administração & dosagem , Hemostáticos/uso terapêutico
15.
Epilepsy Behav ; 156: 109827, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38759429

RESUMO

Safe delivery and optimal peripartum and postpartum care in women with epilepsy (WWE) is a major concern which has received limited attention in recent years. A diagnosis of epilepsy per se is not an indication for a planned cesarean section or induction of labor, even though epidemiological studies indicate that cesarean delivery is more common among WWE compared to the general population. Pregnancy in WWE is associated with an increased risk of obstetrical complications and increased perinatal morbidity and mortality, and these risks may be greater among WWE taking ASMs. Wherever feasible, pregnant WWE should be directed to specialist care. Risk minimization includes, when appropriate, dose adjustment to compensate for pregnancy-related changes in the pharmacokinetics of some ASMs. With respect to postpartum management, WWE should be advised that the benefits of breastfeeding outweigh the small risk of adverse drug reactions in the infant.

16.
BMC Plant Biol ; 24(1): 403, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750434

RESUMO

Cotton (Gossypium barbadense L.) is a leading fiber and oilseed crop globally, but genetic diversity among breeding materials is often limited. This study analyzed genetic variability in 14 cotton genotypes from Egypt and other countries, including both cultivated varieties and wild types, using agro-morphological traits and genomic SSR markers. Field experiments were conducted over two seasons to evaluate 12 key traits related to plant growth, yield components, and fiber quality. Molecular diversity analysis utilized 10 SSR primers to generate DNA profiles. The Molecular diversity analysis utilized 10 SSR primers to generate DNA profiles. Data showed wide variation for the morphological traits, with Egyptian genotypes generally exhibiting higher means for vegetative growth and yield parameters. The top-performing genotypes for yield were Giza 96, Giza 94, and Big Black Boll genotypes, while Giza 96, Giza 92, and Giza 70 ranked highest for fiber length, strength, and fineness. In contrast, molecular profiles were highly polymorphic across all genotypes, including 82.5% polymorphic bands out of 212. Polymorphism information content was high for the SSR markers, ranging from 0.76 to 0.86. Genetic similarity coefficients based on the SSR data varied extensively from 0.58 to 0.91, and cluster analysis separated genotypes into two major groups according to geographical origin. The cotton genotypes displayed high diversity in morphology and genetics, indicating sufficient variability in the germplasm. The combined use of physical traits and molecular markers gave a thorough understanding of the genetic diversity and relationships between Egyptian and global cotton varieties. The SSR markers effectively profiled the genotypes and can help select ideal parents for enhancing cotton through hybridization and marker-assisted breeding.


Assuntos
Fibra de Algodão , Variação Genética , Genótipo , Gossypium , Gossypium/genética , Gossypium/anatomia & histologia , Gossypium/crescimento & desenvolvimento , Repetições de Microssatélites , Egito , Fenótipo
17.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731499

RESUMO

Carbon nanodots (CDs) are commonly found in food products and have attracted significant attention from food scientists. There is a high probability of CD exposure in humans, but its impacts on health are unclear. Therefore, health effects associated with CD consumption should be investigated. In this study, we attempted to create a model system of the Maillard reaction between cystine and glucose using a simple cooking approach. The CDs (CG-CDs) were isolated from cystine-glucose-based Maillard reaction products and characterized using fluorescence spectroscopy, X-ray diffractometer (XRD), and transmission electron microscope (TEM). Furthermore, human mesenchymal stem cells (hMCs) were used as a model to unravel the CDs' cytotoxic properties. The physiochemical assessment revealed that CG-CDs emit excitation-dependent fluorescence and possess a circular shape with sizes ranging from 2 to 13 nm. CG-CDs are predominantly composed of carbon, oxygen, and sulfur. The results of the cytotoxicity evaluation indicate good biocompatibility, where no severe toxicity was observed in hMCs up to 400 µg/mL. The DPPH assay demonstrated that CDs exert potent antioxidant abilities. The qPCR analysis revealed that CDs promote the downregulation of the key regulatory genes, PPARγ, C/EBPα, SREBP-1, and HMGCR, coupled with the upregulation of anti-inflammatory genes. Our findings suggested that, along with their excellent biocompatibility, CG-CDs may offer positive health outcomes by modulating critical genes involved in lipogenesis, homeostasis, and obesity pathogenesis.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT , Carbono , Reação de Maillard , Células-Tronco Mesenquimais , PPAR gama , Proteína de Ligação a Elemento Regulador de Esterol 1 , Humanos , Carbono/química , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Pontos Quânticos/química , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Enxofre/química
18.
Nat Commun ; 15(1): 3994, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734761

RESUMO

NADPH oxidase 5 (NOX5) catalyzes the production of superoxide free radicals and regulates physiological processes from sperm motility to cardiac rhythm. Overexpression of NOX5 leads to cancers, diabetes, and cardiovascular diseases. NOX5 is activated by intracellular calcium signaling, but the underlying molecular mechanism of which - in particular, how calcium triggers electron transfer from NADPH to FAD - is still unclear. Here we capture motions of full-length human NOX5 upon calcium binding using single-particle cryogenic electron microscopy (cryo-EM). By combining biochemistry, mutagenesis analyses, and molecular dynamics (MD) simulations, we decode the molecular basis of NOX5 activation and electron transfer. We find that calcium binding to the EF-hand domain increases NADPH dynamics, permitting electron transfer between NADPH and FAD and superoxide production. Our structural findings also uncover a zinc-binding motif that is important for NOX5 stability and enzymatic activity, revealing modulation mechanisms of reactive oxygen species (ROS) production.


Assuntos
Cálcio , Microscopia Crioeletrônica , Simulação de Dinâmica Molecular , NADPH Oxidase 5 , NADP , Humanos , NADPH Oxidase 5/metabolismo , NADPH Oxidase 5/genética , NADPH Oxidase 5/química , Cálcio/metabolismo , NADP/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Superóxidos/metabolismo , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Zinco/metabolismo , Transporte de Elétrons , Ativação Enzimática , Sítios de Ligação
19.
J Clin Oncol ; : JCO2301951, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691822

RESUMO

PURPOSE: Osteoradionecrosis of the jaw (ORN) can manifest in varying severity. The aim of this study is to identify ORN risk factors and develop a novel classification to depict the severity of ORN. METHODS: Consecutive patients with head and neck cancer (HNC) treated with curative-intent intensity-modulated radiation therapy (IMRT) (≥45 Gy) from 2011 to 2017 were included. Occurrence of ORN was identified from in-house prospective dental and clinical databases and charts. Multivariable logistic regression model was used to identify risk factors and stratify patients into high-risk and low-risk groups. A novel ORN classification system was developed to depict ORN severity by modifying existing systems and incorporating expert opinion. The performance of the novel system was compared with 15 existing systems for their ability to identify and predict serious ORN event (jaw fracture or requiring jaw resection). RESULTS: ORN was identified in 219 of 2,732 (8%) consecutive patients with HNC. Factors associated with high risk of ORN were oral cavity or oropharyngeal primaries, received IMRT dose ≥60 Gy, current/ex-smokers, and/or stage III to IV periodontal condition. The ORN rate for high-risk versus low-risk patients was 12.7% versus 3.1% (P < .001) with an AUC of 0.71. Existing ORN systems overclassified serious ORN events and failed to recognize maxillary ORN. A novel ORN classification system, ClinRad, was proposed on the basis of vertical extent of bone necrosis and presence/absence of exposed bone/fistula. This system detected serious ORN events in 5.7% of patients and statistically outperformed existing systems. CONCLUSION: We identified risk factors for ORN and proposed a novel ORN classification system on the basis of vertical extent of bone necrosis and presence/absence of exposed bone/fistula. It outperformed existing systems in depicting the seriousness of ORN and may facilitate clinical care and clinical trials.

20.
Sci Rep ; 14(1): 11275, 2024 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760415

RESUMO

Limited data exist on viral hepatitis among migrant populations. This study investigated the prevalence of current hepatitis B virus (HBV) infection and lifetime hepatitis C virus (HCV) infection among Qatar's migrant craft and manual workers (CMWs), constituting 60% of the country's population. Sera collected during a nationwide COVID-19 population-based cross-sectional survey on CMWs between July 26 and September 9, 2020, underwent testing for HBsAg and HCV antibodies. Reactive samples underwent confirmatory testing, and logistic regression analyses were employed to explore associations with HBV and HCV infections. Among 2528 specimens tested for HBV infection, 15 were reactive, with 8 subsequently confirmed positive. Three samples lacked sufficient sera for confirmatory testing but were included in the analysis through multiple imputations. Prevalence of current HBV infection was 0.4% (95% CI 0.2-0.7%). Educational attainment and occupation were significantly associated with current HBV infection. For HCV infection, out of 2607 specimens tested, 46 were reactive, and 23 were subsequently confirmed positive. Prevalence of lifetime HCV infection was 0.8% (95% CI 0.5-1.2%). Egyptians exhibited the highest prevalence at 6.5% (95% CI 3.1-13.1%), followed by Pakistanis at 3.1% (95% CI 1.1-8.0%). Nationality, geographic location, and occupation were significantly associated with lifetime HCV infection. HBV infection is relatively low among CMWs, while HCV infection falls within the intermediate range, both compared to global and regional levels.


Assuntos
Hepatite B , Hepatite C , Migrantes , Humanos , Catar/epidemiologia , Hepatite B/epidemiologia , Hepatite B/virologia , Hepatite B/sangue , Feminino , Migrantes/estatística & dados numéricos , Hepatite C/epidemiologia , Adulto , Masculino , Prevalência , Estudos Transversais , Pessoa de Meia-Idade , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/imunologia , Adulto Jovem , COVID-19/epidemiologia , COVID-19/virologia , Adolescente , Antígenos de Superfície da Hepatite B/sangue , Anticorpos Anti-Hepatite C/sangue
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