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1.
ACS Omega ; 9(18): 20322-20330, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38737024

RESUMEN

This study addresses the pivotal challenge of hydrogen production through methane decomposition, offering a pathway to achieving clean energy goals. Investigating the utilization of titania-modified zirconia dual redox supports (10TiZr) in iron or doped iron-based catalysts for the CH4 decomposition reaction, our research involves a thorough characterization process. This includes analyses of the surface area porosity, X-ray diffraction, Raman-infrared spectroscopy, and temperature-programmed reduction/oxidation. The observed sustained enhancement in catalytic activity over extended durations suggests the in situ formation of catalytically active sites. The introduction of Co or Ni into the 30Fe/10TiZr catalyst leads to the generation of a higher density of reducible species. Furthermore, the Ni-promoted 30Fe/10TiZr catalyst exhibits a lower crystallinity, indicating superior dispersion. Notably, the cobalt-promoted 30Fe/10TiZr catalyst achieves over 80% CH4 conversion and H2 yield within 3 h. Additionally, the Ni-promoted 30Fe/10TiZr catalyst attains a remarkable 87% CH4 conversion and 82% H2 yield after 3 h of the continuous process.

2.
Cureus ; 16(3): e56568, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38646263

RESUMEN

BACKGROUND:  Children's bones are at high risk of fracture as they grow. The clinical characteristics of fractures in children differ from those in adults. Studying fractures in healthy children is critical for identifying cases of fragility fractures. The aim of this study was to assess the clinical characteristics of limb fractures as well as clinical indicators of fracture healing outcomes in healthy Saudi children seen in an emergency room. METHODS: A retrospective review of the treatment course of all pediatric fractures and related factors treated at King Abdullah Specialist Children's Hospital (KASCH) in Riyadh between 2016 and 2018 was conducted. Children with a primary bone disorder or chronic comorbidities known to affect bone health were excluded. RESULTS:  The study included 143 patients (mean age ± SD = 8.23 + 3.76 years), and 71% (n = 102) were males. Motor vehicle accidents (MVAs) were the most common mechanism of injury, accounting for 50 (35%) cases, followed by fall injuries, sports injuries, and pedestrian accidents at 45 (31.4%), 16 (11.2%), and 13 (9.1%), respectively. A total of 178 fractures were reported, with the femur (n = 75, 42.1%) being the most common of the reported fracture sites, followed by the forearm (n = 44, 24.7%). The most common type of fracture was transverse fracture (n = 96, 54% of patients). Vitamin D levels were measured in 53/143 cases. Of these, vitamin D deficiency was found in 38 (71.7%) patients. The average time for fracture healing was 32.9 ± 30.2 weeks. The mechanisms of injury, including MVAs and sports injuries, as well as femur and forearm fractures, were clinical factors that were independently associated with a longer duration of fracture healing time (p < 0.001), but age, gender, and vitamin D status were not associated with that outcome. CONCLUSION:  MVAs and fall injuries were the most common causes of fracture in our patients. MVAs and sports injuries were associated with prolonged healing time. Large prospective, multicenter, or field studies may be required to further explore clinical characteristics, outcomes, and environmental factors.

4.
Cureus ; 15(12): e50299, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38089946

RESUMEN

Giant cell arteritis (GCA) is considered the most common type of vasculitis, especially in people aged 50 years or older, and imaging studies have helped predict its systemic nature. We conducted this review to highlight the results of the recently published articles considering the prognosis of giant cell arteritis (GCA). We searched for the relevant literature in SCOPUS, PubMed, Web of Science, and Science Direct and were included. We used Rayyan (Rayyan Systems, Cambridge, Massachusetts) throughout this systematic approach. The search resulted in twelve studies with 2600 patients with GCA diagnosis; most of them, 1853 (71.3%), were females. This systematic review found that most of the GCA patients experienced at least one relapse episode, primarily in patients younger than 75 years, with dependency on glucocorticoids, female sex, and involvement of large vessel vasculitis. We also found that stroke in GCA patients was associated with a bad prognosis. Therefore, we think more prospective studies are needed to enhance particular patient outcomes, and new therapeutic approaches using accessible biotherapies like tocilizumab and other similar medications are required.

5.
Nanomaterials (Basel) ; 13(21)2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37947719

RESUMEN

The catalytic conversion of CH4 and CO2 into H2-rich syngas is known as the dry reforming of methane (DRM). The dissociation of CH4 over active sites, coupled with the oxidation or polymerization of CH4-x (x = 1-4), plays a crucial role in determining in determining the DRM product yield and coke deposition. Herein, a series of bimetallic-supported catalysts are prepared by the dispersion of Ni-M (M = Ce, Co, Fe, and Sr) over 60 wt% MgO-40 wt% Al2O3 (60Mg40Al) support. Catalysts are tested for DRM and characterized with XRD, surface area and porosity, temperature-programmed reduction/desorption, UV-VIS-Raman spectroscopy, and thermogravimetry. 2.5Ni2.5Sr/60Mg40Al and 2.5Ni2.5Fe/60Mg40Al, and 2.5Ni2.5Ce/60Mg40Al and 2.5Ni2.5Co/60Mg40Al have similar CO2 interaction profiles. The 2.5Ni2.5Sr/60Mg40Al catalyst nurtures inert-type coke, whereas 2.5Ni2.5Fe/60Mg40Al accelerates the deposition of huge coke, which results in catalytic inferiority. The higher activity over 2.5Ni2.5Ce/60Mg40Al is due to the instant lattice oxygen-endowing capacity for oxidizing coke. Retaining a high DRM activity (54% H2-yield) up to 24 h even against a huge coke deposition (weight loss 46%) over 2.5Ni2.5Co/60Mg40Al is due to the timely diffusion of coke far from the active sites or the mounting of active sites over the carbon nanotube.

6.
ChemistryOpen ; 12(9): e202300112, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37688328

RESUMEN

Methane decomposition is a promising route to synthesize COx -free hydrogen and carbon nanomaterials (CNMs ). In this work, the impregnation method was employed for the preparation of the catalysts. Systematic investigations on the activity and stability of Fe-based catalysts were carried out in a packed-bed micro-activity reactor at 800 °C with a feed gas flow rate of 18 mL/min. The effect of doping Y2 O3 , MgO, SiO2 and TiO2 over ZrO2 on the catalytic performance was also studied. BET revealed that the specific surface areas and pore volumes are increased after SiO2 , TiO2 , and Y2 O3 are added to ZrO2 while MgO had a negative impact and hence a little decrease in specific surface area is observed. The catalytic activity results showed that the Fe-based catalyst supported over TiO2 -doped ZrO2 that is, Fe-TiZr, demonstrated the highest activity and stability, with a maximum methane conversion of 81.3 % during 180 min time-on-stream. At 800 °C, a maximum initial methane conversion of 73 %, 38 %, 64 %, and 69 % and a final carbon yield of 121 wt. %, 55 wt. %, 354 wt. %, and 174 wt. % was achieved using Fe-MgZr, Fe-SiZr, Fe-TiZr and Fe-YZr catalysts, respectively. Moreover, bulk deposition of uniform carbon nanotubes with a high degree of graphitization and different diameters was observed over the catalysts.

7.
J Diabetes ; 15(5): 397-408, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37078106

RESUMEN

Neprilysin (NEP) is a transmembrane zinc-dependent metalloproteinase that inactivates various peptide hormones including glucagon-like peptide 1 (GLP-1). NEP inhibitors may be effective in the management of type 2 diabetes mellitus (T2DM) by increasing the circulating level of GLP-1. However, acute-effect NEP inhibitors may lead to detrimental effects by increasing blood glucose independent of GLP-1. These findings suggest a controversial point regarding the potential role of NEP inhibitors on glucose homeostasis in T2DM patients. Therefore, this perspective aimed to clarify the controversial points concerning the role of NEP inhibitors on glucose homeostasis in T2DM. NEP inhibitors may lead to beneficial effects by inhibition of NEP, which is involved in the impairment of glucose homeostasis through modulation of insulin resistance. NEP increases dipeptidyl peptidase-4 (DPP4) activity and contributes to increasing active GLP-1 proteolysis so NEP inhibitors may improve glycemic control through increasing endogenous GLP-1 activity and reduction of DPP4 activity. Thus, NEP inhibitors could be effective alone or in combination with antidiabetic agents in treating T2DM patients. However, long-term and short-term effects of NEP inhibitors may lead to a detrimental effect on insulin sensitivity and glucose homeostasis through different mechanisms including augmentation of substrates and pancreatic amyloid deposition. These findings are confirmed in animal but not in humans. In conclusion, NEP inhibitors produce beneficial rather than detrimental effects on glucose homeostasis and insulin sensitivity in humans though most of the detrimental effects of NEP inhibitors are confirmed in animal studies.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Resistencia a la Insulina , Animales , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Neprilisina , Dipeptidil Peptidasa 4 , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Glucemia , Péptido 1 Similar al Glucagón , Homeostasis , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico
8.
Molecules ; 28(5)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36903483

RESUMEN

Oral anticancer therapy mostly faces the challenges of low aqueous solubility, poor and irregular absorption from the gastrointestinal tract, food-influenced absorption, high first-pass metabolism, non-targeted delivery, and severe systemic and local adverse effects. Interest has been growing in bioactive self-nanoemulsifying drug delivery systems (bio-SNEDDSs) using lipid-based excipients within nanomedicine. This study aimed to develop novel bio-SNEDDS to deliver antiviral remdesivir and baricitinib for the treatment of breast and lung cancers. Pure natural oils used in bio-SNEDDS were analyzed using GC-MS to examine bioactive constituents. The initial evaluation of bio-SNEDDSs were performed based on self-emulsification assessment, particle size analysis, zeta potential, viscosity measurement, and transmission electron microscopy (TEM). The single and combined anticancer effects of remdesivir and baricitinib in different bio-SNEDDS formulations were investigated in MDA-MB-231 (breast cancer) and A549 (lung cancer) cell lines. The results from the GC-MS analysis of bioactive oils BSO and FSO showed pharmacologically active constituents, such as thymoquinone, isoborneol, paeonol and p-cymenene, and squalene, respectively. The representative F5 bio-SNEDDSs showed relatively uniform, nanosized (247 nm) droplet along with acceptable zeta potential values (+29 mV). The viscosity of the F5 bio-SNEDDS was recorded within 0.69 Cp. The TEM suggested uniform spherical droplets upon aqueous dispersions. Drug-free, remdesivir and baricitinib-loaded bio-SNEDDSs (combined) showed superior anticancer effects with IC50 value that ranged from 1.9-4.2 µg/mL (for breast cancer), 2.4-5.8 µg/mL (for lung cancer), and 3.05-5.44 µg/mL (human fibroblasts cell line). In conclusion, the representative F5 bio-SNEDDS could be a promising candidate for improving the anticancer effect of remdesivir and baricitinib along with their existing antiviral performance in combined dosage form.


Asunto(s)
Neoplasias de la Mama , Neoplasias Pulmonares , Nanopartículas , Humanos , Femenino , Reposicionamiento de Medicamentos , Administración Oral , Emulsiones , Sistemas de Liberación de Medicamentos/métodos , Solubilidad , Aceites , Tamaño de la Partícula , Disponibilidad Biológica , Tensoactivos , Liberación de Fármacos
9.
Vaccines (Basel) ; 11(2)2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36851085

RESUMEN

The objective of this study is to assess the frequency and severity of adverse events following immunization (AEFI) in Indian children aged 5-17 years who received the Pfizer-BioNTech mRNA COVID-19 vaccine, as well as to investigate for predictors of AEFI. To examine AEFI following the first and second doses of Pfizer's vaccine, semi-structured questionnaires were distributed as Google forms at Indian schools in Saudi Arabia. The 385 responses included 48.1% male and 51.9% female children, with 136 responses of children aged 5-11 years (group A) and 249 responses from children aged 12-17 years (group B). Overall, 84.4% of children had two shots. The frequency of AEFI was reported to be higher after the first dose than after the second (OR = 2.12, 95% CI = 1.57-2.86). The reported AEFIs included myalgia, rhinitis, local reaction with fever, a temperature of 102 °F or higher, and mild to moderate injection site reactions. While group B frequently reported multiple AEFIs, group A typically reported just one. Local reaction with low grade fever was more frequently reported in group B after the first dose (24.1%) and second dose (15.4%), while local reaction without low grade fever was most frequently observed in group A after the first (36.8%) and second dose (30%). Only prior COVID-19 infection (OR = 2.98, 95% CI = 1.44-6.2) was associated with AEFI after the second dose in the study sample, whereas male gender (OR = 1.71, 95% CI = 1.13-2.6) and prior COVID-19 infection (OR = 2.95, 95% CI = 1.38-6.3) were predictors of AEFI after the first dose. Non-serious myocarditis was reported by only one child. According to the analysis conducted, the Pfizer's mRNA COVID-19 vaccination was found to be safe in Indian children.

10.
Materials (Basel) ; 16(3)2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36770167

RESUMEN

The dry reforming of methane (DRM) was studied for seven hours at 800 °C and 42 L/(g·h) gas hourly space velocity over Ni-based catalysts, promoted with various amounts of gadolinium oxide (x = 0.0, 1.0, 2.0, 3.0, 4.0, and 5.0 wt.%) and supported on mesoporous yttrium-zirconium oxide (YZr). The best catalyst was found to have 4.0 wt.% of gadolinium, which resulted in ∼80% and ∼86% conversions of CH4 and CO2, respectively, and a mole ratio of ∼0.90 H2/CO. The addition of Gd2O3 shifted the diffraction peaks of the support to higher angles, indicating the incorporation of the promoter into the unit cell of the YZr support. The Gd2O3 promoter improved the catalyst basicity and the interaction of NiO with support, which were reflected in the coke resistance (6.0 wt.% carbon deposit on 5Ni+4Gd/YZr; 19.0 wt.% carbon deposit on 5Ni/YZr) and the stability of our catalysts. The Gd2O3 is believed to react with carbon dioxide to form oxycarbonate species and helps to gasify the surface of the catalysts. In addition, the Gd2O3 enhanced the activation of CH4 and its conversion on the metallic nickel sites.

12.
Cureus ; 14(1): e21131, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35165584

RESUMEN

Diabetes mellitus is a prevalent metabolic disorder that has a wide range of complications. Neurological complications are common and include stroke and peripheral neuropathy. However, hemichorea is a very rare manifestation of diabetes mellitus. Chorea can be due to primary inherited conditions or secondary to other disorders. Careful evaluation of patients with chorea is crucial since secondary chorea can be managed with the treatment of the underlying cause. We report the case of a 51-year-old man who presented to the emergency department with a two-week history of sudden involuntary and random-appearing movements of the right upper and lower extremities. These movements were non-suppressible and disappeared during sleep. Further, the movements were not associated with any neurological symptoms, including headache, dizziness, weakness, sensory deficits, or loss of consciousness. The patient had a longstanding history of hypertension and diabetes mellitus. He reported that he was not compliant with his medications. Laboratory investigation revealed a very high level of blood glucose (580 mg/dL) with associated pseudohyponatreamia (127 mEq/L). Head computed tomography scan showed increased density in right caudate nuclei and putamen with no surrounding edema or mass effect. The findings were suggestive of non-ketotic hyperglycemic hemichorea based on the clinical, laboratory, and radiological laboratory findings. The patient received insulin therapy according to sliding-scale protocol. The chorea movements gradually improved and completely disappeared after the fourth day of admission with the normalization of glucose level. In view of this, emergency medicine physicians should consider non-ketotic hyperglycemia as a potential underlying etiology of acute hemichorea.

13.
Front Endocrinol (Lausanne) ; 12: 669302, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33868185

RESUMEN

Background: Overburdened healthcare systems during the coronavirus disease (COVID-19) pandemic led to suboptimal chronic disease management, including that of pediatric type 1 diabetes mellitus (T1DM). The pandemic also caused delayed detection of new-onset diabetes in children; this increased the risk and severity of diabetic ketoacidosis (DKA). We therefore investigated the frequency of new-onset pediatric T1DM and DKA in Saudi Arabia during the COVID-19 pandemic and compared it to the same period in 2019. Methods: We conducted a multicenter retrospective cohort study, including patients aged 1-14 years admitted with new-onset T1DM or DKA during the COVID-19 pandemic (March-June 2020) and the same period in 2019. We assessed factors including age, sex, anthropometric measures, nationality, duration of diabetes, diabetes management, HbA1c levels, glycemic control, cause of admission, blood gas levels, etiology of DKA, DKA complications, length of hospital stay, and COVID-19 test status. Result: During the lockdown, 106 children, compared with 154 in 2019, were admitted to 6 pediatric diabetes centers. Among the admissions, DKA was higher in 2020 than in 2019 (83% vs. 73%; P=0.05; risk ratio=1.15; 95% confidence interval, 1.04-1.26), after adjusting for age and sex. DKA frequency among new-onset T1DM and HbA1c levels at diagnosis were higher in 2020 than in 2019 (26% vs. 13.4% [P=<0.001] and 12.1 ± 0.2 vs. 10.8 ± 0.25 [P<0.001], respectively). Females and older patients had a higher risk of DKA. Conclusion: The lockdown implemented in Saudi Arabia has significantly impacted children with T1DM and led to an increased DKA frequency, including children with new-onset T1DM, potentially owing to delayed presentation.


Asunto(s)
COVID-19 , Diabetes Mellitus Tipo 1/epidemiología , Cetoacidosis Diabética/epidemiología , Pandemias , Cuarentena/estadística & datos numéricos , Factores de Edad , Antropometría , Análisis de los Gases de la Sangre , Niño , Estudios de Cohortes , Diabetes Mellitus Tipo 1/terapia , Cetoacidosis Diabética/terapia , Manejo de la Enfermedad , Femenino , Hemoglobina Glucada , Control Glucémico , Humanos , Tiempo de Internación , Masculino , Arabia Saudita/epidemiología , Factores Sexuales
14.
Chemosphere ; 242: 125181, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31671301

RESUMEN

Recognizing the vast uses of water in human life, the presence of α and ß particles emitting radionuclides in groundwater of northern Saudi Arabia has been evaluated as a means of water quality assessment of the region. A liquid scintillation counting technique was used to determine the gross α/ß, and 228Ra radioactivities in water samples, while the radioactivity concentrations of 234,238U and 226Ra were determined using alpha spectrometry after the separation process. Present results show that all water samples contain a higher level of gross α and ß radioactivity than the WHO recommended limits; the average gross α activity is about 7 times greater than the limit value of 0.5 Bq L-1, while the average gross ß activity value is about 3.5 times greater than the limit value of 1 Bq L-1. Correlations of TDS and pH with gross α and ß radioactivity in the studied samples were investigated. The activity ratio of the measured U and Ra alpha emitters to the gross α radioactivity and the ratio of the measured ß emitters to gross ß radioactivity were also discussed. Furthermore, interesting information on thorium abundance and radioactive disequilibrium in U series were observed by studying the activity ratio of 228Ra/226Ra, 226Ra/238U, and 234U/238U. Although these samples are not directly used for human being drinking, and mainly used in irrigation, the higher gross α/ß radioactivity may cause health risks to humans, since these radionuclides may enter the food chain through irrigation water. Thus, further radioactive risk assessment is highly recommended.


Asunto(s)
Agua Subterránea/análisis , Radioisótopos/análisis , Medición de Riesgo , Contaminantes Radiactivos del Agua/análisis , Humanos , Monitoreo de Radiación/métodos , Radiactividad , Radio (Elemento)/análisis , Arabia Saudita , Torio/análisis , Uranio/análisis
15.
Chemosphere ; 210: 511-515, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30025369

RESUMEN

This study aims to assess the committed effective dose due to the intake of 210Po from the consumption of fish in Arabian Gulf countries. Twenty different kinds of fish, which represent the most common fish species consumed in the Arabian Gulf countries, were analyzed using alpha spectrometer technique. 210Po activity concentrations in fish samples were found to vary over a wide range from 0.1 to 14.7 Bq kg-1 fresh weight. This variation of 210Po concentrations between various type of fish samples might be attributed to the feeding type pattern and the size of fish. The annual committed effective dose due to ingestion of 210Po in fish species for adults in the Arabian Gulf countries was estimated and found to vary from 38 µSv in Bahrain to 85 µSv in Oman with an average value of 59 µSv. These values are considered relatively high compared to those reported in some other regions. However, it is still much lower than the world average ingestion dose due to natural radiation sources.


Asunto(s)
Peces/metabolismo , Polonio/análisis , Animales , Ingestión de Alimentos , Contaminación de Alimentos , Medio Oriente , Polonio/farmacología , Monitoreo de Radiación , Contaminantes Radiactivos del Agua/análisis
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