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1.
RSC Adv ; 14(31): 22569-22581, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39021457

RESUMO

Recycling gold from electronic waste offers significant benefits for both environmental protection and resource sustainability. However, this process presents considerable challenges due to high costs, prolonged processing times, and interference from coexisting metals. In this study, we synthesized a hybrid mesoporous nanocomposite comprising platelets-like CoNi2S4 incorporated with g-C3N4 nanosheets (CoNi2S4@g-C3N4) for the selective recovery of gold (Au(iii)) ions from spent computer motherboards. Comprehensive characterization of the CoNi2S4@g-C3N4 nanocomposite was conducted, including its physicochemical properties, textural and structural characteristics, morphology, and elemental composition. The CoNi2S4@g-C3N4 extractor demonstrated an exceptional adsorption capacity of 200.6 mg g-1, with high selectivity at pH 2, rapid equilibrium time of 60 minutes, and satisfactory reusability for over ten cycles. Adsorption isotherm and kinetic studies revealed that the CoNi2S4@g-C3N4 nanocomposite adheres to the Langmuir adsorption model and the pseudo-second-order kinetic model for Au(iii) ion adsorption. Overall, this study introduces a viable adsorbent that shows considerable promise for industrial-scale Au(iii) extraction from e-waste.

2.
Fundam Clin Pharmacol ; 38(4): 742-757, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38325396

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the most widespread type of primary liver cancer. Diethylnitrosamine (DEN), a hepatotoxic hepatocarcinogenic compound, is used to induce HCC in animal models. The non-selective ß-blocker propranolol demonstrated antiproliferative activity in many cancer types. OBJECTIVE: This investigation aimed to evaluate the anticancer effect of propranolol against DEN-induced HCC in rats. METHODS: Thirty adult male rats were divided into the following groups: Group I (C, control), Group II (HCC); received DEN, 70 mg/kg body weight (b.wt.) once a week for 10 weeks, to induce HCC, and Group III (HCC/Prop); received DEN for 10 weeks for HCC induction, then received 20 mg/kg b.wt. propranolol, intraperitoneally for four successive weeks. RESULTS: HCC was developed in rats' livers and confirmed via significant liver architecture changes, significantly elevated activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST), α-fetoprotein (AFP), total- and direct-bilirubin (Bil), and a decline in albumin (ALB) level in serum. HCC group demonstrated elevated levels of malondialdehyde (MDA), nitric oxide (NO), HIF-1α, IL-8, NF-κB, PGE2, TGF-ß1, VEGF, and CD8, but significant decline of GSH, and IL-10 level, with suppression of the antioxidant enzymes' activities. In addition, the gene expression of the hepatic inducible nitric oxide synthase (iNOS), and LAG-3 were up-regulated. Moreover, the protein expression of p-PKC was up-regulated, while that of PD-1 and PD-L1 were down-regulated in the liver tissues of the HCC group. However, propranolol ameliorated the investigated parameters in the HCC/Prop group. CONCLUSION: Propranolol exhibited an anticancer effect and thus can be considered as a promising treatment for HCC. Blocking of PD-1/PD-L1 and LAG-3 signals participated in the anti-tumor effect of propranolol on HCC.


Assuntos
Carcinoma Hepatocelular , Dietilnitrosamina , Propranolol , Animais , Dietilnitrosamina/toxicidade , Masculino , Propranolol/farmacologia , Ratos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/induzido quimicamente , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/patologia , Antineoplásicos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Modelos Animais de Doenças , Antagonistas Adrenérgicos beta/farmacologia
3.
Nat Commun ; 15(1): 938, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296966

RESUMO

Electrochemical conversion of CO2 offers a sustainable route for producing fuels and chemicals. Pd-based catalysts are effective for converting CO2 into formate at low overpotentials and CO/H2 at high overpotentials, while undergoing poorly understood morphology and phase structure transformations under reaction conditions that impact performance. Herein, in-situ liquid-phase transmission electron microscopy and select area diffraction measurements are applied to track the morphology and Pd/PdHx phase interconversion under reaction conditions as a function of electrode potential. These studies identify the degradation mechanisms, including poisoning and physical structure changes, occurring in PdHx/Pd electrodes. Constant potential density functional theory calculations are used to probe the reaction mechanisms occurring on the PdHx structures observed under reaction conditions. Microkinetic modeling reveals that the intercalation of *H into Pd is essential for formate production. However, the change in electrochemical CO2 conversion selectivity away from formate and towards CO/H2 at increasing overpotentials is due to electrode potential dependent changes in the reaction energetics and not a consequence of morphology or phase structure changes.

4.
Hum Reprod ; 38(5): 830-839, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36881694

RESUMO

STUDY QUESTION: Does the occurrence of non-visualized pregnancy loss (NVPL) affect future reproductive outcomes in patients with recurrent pregnancy loss (RPL)? SUMMARY ANSWER: The number of previous NVPLs is a significant predictor of subsequent live birth in patients with RPL. WHAT IS KNOWN ALREADY: The number of preceding miscarriages is a strong indicator for future reproductive outcomes. However, NVPL particularly has been sparsely addressed in previous literature. STUDY DESIGN, SIZE, DURATION: We performed a retrospective cohort study of 1981 patients attending a specialized recurrent pregnancy loss clinic (RPL) from January 2012 to March 2021. A total of 1859 patients met the inclusion criteria of the study and were included in the analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients with a history of RPL, defined as ≥2 pregnancy losses before 20 weeks gestation, who attended a specialized RPL clinic in a tertiary care center were included. Patients' evaluation included parental karyotyping, antiphospholipid antibodies screening, uterine cavity assessment with hysterosalpingography (HSG) or hysteroscopy, maternal thyroid stimulating hormone (TSH) testing, and serum hemoglobin A1C testing. Other investigations were performed only when indicated such as testing for inherited thrombophilias, serum prolactin, oral glucose tolerance test, and endometrial biopsy. Patients were divided into three groups; patients who experienced NVPLs only (pure NVPLs group), patients with only visualized pregnancy losses (pure VPLs group), and patients with history of both NVPLs and VPLs (mixed group). Statistical analysis was performed using Wilcoxon rank-sum tests for continuous variables and Fisher's exact tests for categorical variables. Significance was detected when P values <0.05. A logistic regression model was used to determine the impact of NVPLs and VPLs numbers on any live birth subsequent to the initial RPL clinic visit. MAIN RESULTS AND THE ROLE OF CHANCE: The prevalence of patients with pure NVPLs, pure VPLs, and mixed losses was 14.7% (274/1859), 31.8% (591/1859), and 53.5% (994/1859), respectively. The prevalence of acquired and congenital uterine anomalies diagnosed by HSG or hysteroscopy was significantly different between pure NVPLs, pure VPLs, and mixed groups (16.8% versus 23.7% versus. 20.7%, respectively P = 0.05). There were no significant differences in the results of other RPL investigations or baseline demographics between the three groups. A logistic regression model controlling for maternal age at the initial RPL clinic visit and the follow-up duration showed that the numbers of NVPLs (odds ratio (OR): 0.77, CI: 0.68-0.88) and VPLs (OR: 0.75, CI: 0.64-0.86) are strong predictors for subsequent live births after the initial RPL clinic visit (P < 0.001). The odds of having a live birth decreased by 23% and 25% with each additional NVPL and VPL, respectively. LIMITATIONS, REASONS FOR CAUTION: This study may be limited by its retrospective design. Some of our data, including home pregnancy tests and obstetric history, are based on patient self-reporting, which could have overstated the true prevalence of NVPLs. Another limitation is the lack of available live birth data for all patients at the time of the analysis. WIDER IMPLICATIONS OF THE FINDINGS: To our knowledge, this is the first study to examine and analyze the reproductive outcomes of patients with pure NVPLs in a substantial cohort of patients with RPL. NVPLs seem to affect future live births the same way as clinical miscarriages, which supports their inclusion in RPL definitions. STUDY FUNDING/COMPETING INTEREST(S): This study was supported in part by Canadian Institute Heath Grant (CIHR): Reference Number/W11-179912 and Women's Health Research Institute (WHRI), Vancouver, BC, Canada. M.A.B: Research grants from Canadian Institute for Health Research (CIHR) and Ferring Pharmaceutical. M.A.B. is on the advisory board for AbbVie and Baxter. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Aborto Habitual , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Prevalência , Canadá , Aborto Habitual/etiologia , Nascido Vivo , Taxa de Gravidez
5.
J Ultrasound ; 26(1): 301-306, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36617380

RESUMO

Acute kidney injury (AKI) is frequently associated with alterations in fluid balance making accurate assessment of hemodynamics a vital component of patient management. Unfortunately, conventional parameters such as history, physical examination, vital signs, weight, natriuretic peptides have limitations in this regard. Point of care ultrasonography (POCUS) is a clinician-performed limited ultrasound study intended to answer focused clinical questions at the bedside. In the past several years, it has evolved as an extension of physical examination in various medical specialties. Herein, we describe a case of AKI where nephrologist-performed multi-organ POCUS aided in accurate diagnosis of fluid overload state. In addition, we describe how venous Doppler (VExUS) evaluation can be used to monitor the efficacy of decongestive therapy in real-time. Nephrologists should adopt a multi-parametric approach integrating all the pieces of hemodynamic puzzle when evaluating patients with AKI and fluid/electrolyte disorders.


Assuntos
Injúria Renal Aguda , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Nefrologistas , Ultrassonografia , Ultrassonografia Doppler , Injúria Renal Aguda/diagnóstico por imagem , Injúria Renal Aguda/terapia
7.
Qatar Med J ; 2022(1): 1, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574236

RESUMO

BACKGROUND: Acute pulmonary embolism (PE) is a common and potentially life-threatening condition. This comprehensive study from a Gulf Cooperation Council (GCC) country aimed to evaluate the clinical, radiological, and outcome characteristics associated with acute PE. METHODS: This retrospective observational study analyzed data of patients with confirmed acute PE who were admitted to the largest academic tertiary center in the State of Qatar from January 1, 2014, to December 31, 2018. Data on the clinical presentation, radiologic, and echocardiographic findings, as well as outcomes were collected. RESULTS: A total of 436 patients were diagnosed with acute PE during the study period (male, 53%). Approximately 56% of the patients were < 50 years old at presentation, with a median age of 47 years. In approximately 69% of cases, the PE occurred outside the hospital. The main associated comorbidities were obesity (34.6%), hypertension (29.4%), and diabetes (25%). Immobilization (25.9%) and recent surgery (20.6%) were the most common risk factors. The most frequent presenting symptom was dyspnea (39.5%), and the most frequent signs were tachycardia (49.8%) and tachypnea (45%). Cardiac arrest was the initial presentation in 2.2% of cases. Chest X-ray findings were normal in 41%. On computed tomography pulmonary angiography (CTPA), 41.3% of the patients had segmental PE, 37.1% had central PE, and 64.1% had bilateral PE. The main electrocardiographic (ECG) abnormality was sinus tachycardia (98%). In patients who underwent echocardiography, right ventricular (RV) enlargement was the main echocardiographic finding (36.4%). Low-, intermediate-, and high-risk PE constituted 49.8%, 31.4%, and 18.8% of the cases, respectively. Thrombolysis was prescribed in 8.3% of the total and 24.4% of the high-risk PE cases. Complications of PE and its treatment (from admission up to 6 months post-discharge) included minor bleeding (14%), major bleeding (5%), PE recurrence (4.8%), and chronic thromboembolic pulmonary hypertension (CTEPH) (5%). A total of 15 (3.4%) patients died from PE. CONCLUSIONS: Acute PE can manifest with complex and variable clinical and radiological syndromes. Striking findings in this study are the younger age of acute PE occurrence and the low PE-related mortality rate.

8.
Libyan J Med ; 17(1): 2044597, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35227164

RESUMO

The central location, the size, and instability of saddle pulmonary embolism (PE) have raised considerable concerns regarding its hemodynamic consequences and the optimal management approach. Sparse and conflicting reports have addressed these concerns in the past. We aimed to evaluate the clinical presentation, hemodynamic and echocardiographic effects, as well as the outcomes of saddle PE, and compare the results with those of non-saddle type. This was a retrospective study of 432 adult patients with saddle and non-saddle PE. Overall, 432 patients were diagnosed with PE by computed tomography pulmonary angiography (CTPA). Seventy-three (16.9%) had saddle PE, and 359 had non-saddle PE. Compared to those with non-saddle PE, patients with saddle PE presented more frequently with tachycardia (68.5% vs. 46.2%, P= .001), and tachypnea (58.9% vs. 42.1%, P= .009) on admission, required more frequent intensive care unit (ICU) admissions (45.8% vs. 26.6%, P= .001) and thrombolysis/thrombectomy use (19.1% vs. 6.7%, P= .001), and were at more risk of developing decompensation and cardiac arrest after their initial admission (15.3% vs. 5.9%, P= .006). On echocardiography, right ventricular (RV) enlargement (60% vs. 31.1%, P= .000), RV dysfunction (45.8% vs. 22%, P= .000), and RV systolic pressure (RVSP) of greater than 40 mmHg (61.5% vs. 39.2%, P= .003) were significantly more observed with saddle PE. The two groups did not differ concerning the rates of hypotension (17.8% vs. 18.7%, P= .864) and hypoxemia (41.1% vs. 34.3%, P= .336) on admission and mortality rates. A logistic regression model indicated that the use of oral contraceptive pills (OCP), RVSP > 40 mmHg, and development of hypotension and decompensation following admission were associated with an increased likelihood of having saddle embolus. Saddle PE accounts for a higher proportion among all PE cases than previously reported. Patients with saddle PE tend to present more frequently with adverse hemodynamic and echocardiographic changes and decompensate after their initial presentation. OCP use, development of hypotension, and decompensation following admission and RVSP > 40 mmHg are significant predictors of saddle PE. These characteristics should not be overlooked when managing patients with saddle PE.


Assuntos
Embolia Pulmonar , Disfunção Ventricular Direita , Adulto , Ecocardiografia , Humanos , Embolia Pulmonar/complicações , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/epidemiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Disfunção Ventricular Direita/complicações , Disfunção Ventricular Direita/diagnóstico por imagem
9.
J Nucl Cardiol ; 29(3): 1389-1401, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33474694

RESUMO

BACKGROUND: The presence of myocardial scar in CS patients results in poor prognosis and worse outcomes. 18F-fluorodeoxyglucose (18F-FDG) PET/CT excels at visualizing inflammation but is suboptimal at detecting scar. We evaluated PET/CT sensitivity to detect scar and investigated the incremental diagnostic value of automated PET-derived data. METHODS: 176 patients who underwent cardiac magnetic resonance (CMR) and N-13 ammonia/18F-FDG cardiac PET/CT for suspected CS within 3 months were enrolled. Scar was defined as late gadolinium enhancement (LGE) on CMR without concordant 18F-FDG uptake on 18F-FDG PET/CT. Accuracy of cardiac PET/CT at detecting scar (perfusion defect without concordant 18F-FDG uptake) was assessed before and after addition of automated PET-derived data. RESULTS: Sensitivity of PET/CT for scar detection was 45.3% (specificity 88.9%). Addition of PET-derived LV volumes and function in a logistic regression model improved sensitivity to 57.0% (specificity: 80.0%, AUC 0.72). Addition of phase analysis maximum segmental onset of myocardial contraction > 61 improved AUC to 0.75, correctly relabeling 16.3% of patients as scar (net reclassification index 8.2%). CONCLUSION: Sensitivity of gated PET MPI alone for scar detection in CS is suboptimal. Adding PET-derived volumes/function and phase analysis data results in improved detection and characterization of scar.


Assuntos
Miocardite , Sarcoidose , Cicatriz/diagnóstico por imagem , Meios de Contraste , Fluordesoxiglucose F18 , Gadolínio , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sarcoidose/diagnóstico por imagem , Sarcoidose/patologia
10.
Adv Mater ; 33(45): e2103812, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34541731

RESUMO

The oxygen evolution reaction (OER) limits the energy efficiency of electrocatalytic systems due to the high overpotential symptomatic of poor reaction kinetics; this problem worsens over time if the performance of the OER electrocatalyst diminishes during operation. Here, a novel synthesis of nanocrystalline Ni-Co-Se using ball milling at cryogenic temperature is reported. It is discovered that, by anodizing the Ni-Co-Se structure during OER, Se ions leach out of the original structure, allowing water molecules to hydrate Ni and Co defective sites, and the nanoparticles to evolve into an active Ni-Co oxyhydroxide. This transformation is observed using operando X-ray absorption spectroscopy, with the findings confirmed using density functional theory calculations. The resulting electrocatalyst exhibits an overpotential of 279 mV at 0.5 A cm-2 and 329 mV at 1 A cm-2 and sustained performance for 500 h. This is achieved using low mass loadings (0.36 mg cm-2 ) of cobalt. Incorporating the electrocatalyst in an anion exchange membrane water electrolyzer yields a current density of 1 A cm-2 at 1.75 V for 95 h without decay in performance. When the electrocatalyst is integrated into a CO2 -to-ethylene electrolyzer, a record-setting full cell voltage of 3 V at current density 1 A cm-2 is achieved.

11.
Cardiovasc J Afr ; 32(5): 248-253, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34169959

RESUMO

BACKGROUND: Premature ventricular contraction (PVC) is considered one of the most common arrhythmias in clinical practice. The aetiology of PVC is still unclear, however increased sympathetic activity, electrolyte misbalance and cardiomyopathies are considered the main causes of PVCs. In this study we were trying to find out whether there was any association between PVC burden and elevated left ventricular (LV) filling pressure. METHODS: A total of 100 patients (age: 58.6 ± 7.5 years, 52 males) with frequent PVCs observed on 24-hour Holter monitoring (> 1%) and normal LV ejection fraction (LVEF) (> 50% on echocardiography) were enrolled. Clinical characteristics and echocardiographic parameters, including E/E' to assess LV filling pressure of the patients, were compared with those of an age- and gender-matched control group (n = 100, age: 57.4 ± 7.5 years, 50 males). RESULTS: Mean E' was significantly higher in the controls (7.9 ± 3.1 cm/s) than the cases (6.4 ± 1.9 cm/s) (p = 0.010) while mean E/E' was significantly higher in the cases (12.5 ± 5.3) than the controls (10.9 ± 5.7) (p = 0.044), reflecting significantly different LV diastolic function. However LVEF by M-mode and biplane imaging showed no significant difference between the groups. CONCLUSION: Patients with frequent PVCs were associated with high LV filling pressure, which was significantly different from LV filling pressure in the control group.


Assuntos
Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Complexos Ventriculares Prematuros , Idoso , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Disfunção Ventricular Esquerda/epidemiologia , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/epidemiologia , Pressão Ventricular
12.
Angew Chem Int Ed Engl ; 60(32): 17472-17480, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33823079

RESUMO

Understanding the differences between reactions driven by elevated temperature or electric potential remains challenging, largely due to materials incompatibilities between thermal catalytic and electrocatalytic environments. We show that Ni, N-doped carbon (NiPACN), an electrocatalyst for the reduction of CO2 to CO (CO2 R), can also selectively catalyze thermal CO2 to CO via the reverse water gas shift (RWGS) representing a direct analogy between catalytic phenomena across the two reaction environments. Advanced characterization techniques reveal that NiPACN likely facilitates RWGS on dispersed Ni sites in agreement with CO2 R active site studies. Finally, we construct a generalized reaction driving-force that includes temperature and potential and suggest that NiPACN could facilitate faster kinetics in CO2 R relative to RWGS due to lower intrinsic barriers. This report motivates further studies that quantitatively link catalytic phenomena across disparate reaction environments.

13.
Arab J Gastroenterol ; 21(2): 69-75, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32439237

RESUMO

Liver transplantation is considered the ultimate solution for patients with end-stage chronic liver disease or acute liver failure. Patients with liver transplant need special care starting from preoperative preparation, surgical intervention ending with postoperative care. Transplanted patients have to receive immunosuppressive therapy to prevent rejection. Such a state of immune suppression could predispose to different types of infections in liver transplant recipients. Currently, the world is suffering a pandemic caused by a new strain of the coronavirus family called COVID-19. Certain infection control precautions are needed to protect immunocompromised and vulnerable patients, including liver transplant candidates and recipients from acquiring COVID-19 infection. Restricting non-transplant elective surgical procedures, managing transplant patients in separate outpatient clinics, and in-patient wards can prevent transmission of infection both to patients and healthcare workers. Telemedicine can help in the triage of patients to screen for symptoms of COVID-19 before their regular appointment. Management of immunosuppressive therapy and drug-drug interactions in liver transplant recipients infected with COVID-19 should be cautiously practiced to prevent rejection and effectively treat the underlying infection. In this report, we are trying to summarize available evidence about different aspects of the management of liver transplant candidates and recipients in the era of COVID-19.


Assuntos
Infecções por Coronavirus , Transmissão de Doença Infecciosa/prevenção & controle , Doença Hepática Terminal , Controle de Infecções/métodos , Falência Hepática Aguda , Transplante de Fígado/métodos , Pandemias , Pneumonia Viral , Betacoronavirus/isolamento & purificação , COVID-19 , Comorbidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Doença Hepática Terminal/epidemiologia , Doença Hepática Terminal/cirurgia , Humanos , Falência Hepática Aguda/epidemiologia , Falência Hepática Aguda/cirurgia , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , SARS-CoV-2
14.
Angew Chem Int Ed Engl ; 59(10): 4043-4050, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31919948

RESUMO

Ni,N-doped carbon catalysts have shown promising catalytic performance for CO2 electroreduction (CO2 R) to CO; this activity has often been attributed to the presence of nitrogen-coordinated, single Ni atom active sites. However, experimentally confirming Ni-N bonding and correlating CO2 reduction (CO2 R) activity to these species has remained a fundamental challenge. We synthesized polyacrylonitrile-derived Ni,N-doped carbon electrocatalysts (Ni-PACN) with a range of pyrolysis temperatures and Ni loadings and correlated their electrochemical activity with extensive physiochemical characterization to rigorously address the origin of activity in these materials. We found that the CO2 R to CO partial current density increased with increased Ni content before plateauing at 2 wt % which suggests a dispersed Ni active site. These dispersed active sites were investigated by hard and soft X-ray spectroscopy, which revealed that pyrrolic nitrogen ligands selectively bind Ni atoms in a distorted square-planar geometry that strongly resembles the active sites of molecular metal-porphyrin catalysts.

15.
Egypt J Immunol ; 26(1): 55-67, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31332996

RESUMO

Diabetes Mellitus (D.M.) is a disease with a high and increasing prevalence. The Insulin- producing Cells (IPCs) derived from the Wharton's jelly of human umbilical cord transplantation was thought to be the most promising strategy for treating Diabetes. This study aimed to evaluate IPCs immune modulatory changes occurred after transplanted through two different routes and the effect of these changes on their therapeutic efficiency in relation to transplantation microenvironment. Insulin Producing Cells was induced to differentiate from human Umbilical Cord-Mesenchymal Stem Cells and characterized by morphology under phase contrast inverted microscope and staining of secretory granules by DTZ (diphenylthiocarbonazone) stain, then therapeutic effect was evaluated both in vitro and in vivo through glucose challenge test and hyperglycemia correction in STZ (streptozotocin)- induced diabetic rats. Immune-modulatory changes evaluated by cell- mediated lysis assay and Syber green quantification of immune inflammatory cytokines (IFN- , TGF- ß and IL-10) gene expression by real-time PCR. We observed that in spite of the weak immunogenicity of induced IPCs derived from HUC-MSCs in vitro, but when transplanted in vivo especially through the intra portal vein they could induce an immune response when interact with the disease microenvironment resulting in different degree of inflammatory response. Therefore, the relationship between disease microenvironment and immune alteration should be examined before transplantation therapy.


Assuntos
Diabetes Mellitus Experimental/imunologia , Insulinas , Transplante de Células-Tronco Mesenquimais , Geleia de Wharton/citologia , Animais , Diferenciação Celular , Citocinas/imunologia , Diabetes Mellitus Experimental/terapia , Humanos , Células-Tronco Mesenquimais/citologia , Ratos , Cordão Umbilical/citologia
16.
Egypt Heart J ; 70(4): 315-321, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30591749

RESUMO

BACKGROUND AND OBJECTIVES: Early repolarization pattern (ERP) is not uncommon electrocardiography (ECG) finding and could be associated with arrhythmia and sudden cardiac death (SCD). We aimed to prospectively determine the prevalence of ERP and its association with arrhythmia and SCD during one-year follow-up in an outpatient Egyptian cohort. METHODS: Clinical assessment and ECG were performed to 1850 consecutive individuals presented at the outpatient clinic of Suez Canal University Hospital (SCUH). Then, the ERP group and 100 age and gender-matched ERP -ve controls had undergone echocardiography, 24-h Holter ECG and exercise stress ECG. RESULTS: ERP was found in 124 individuals (6.7%); we excluded 24 patients with structural heart disease. ERP group (No. = 100) were relatively young (80% <50 years-old) and showed male preponderance (60%). ERP frequencies were: inferolateral (50%), antero-lateral (38%), inferior (10%), and global (2%). ERP subjects were leaner than controls (BMI was 25.3 vs. 30 kg/m2, P value < 0.001) and achieved more metabolic equivalents (METS) on stress ECG (10.7 vs. 8.5 METS, P value < 0.01). Only 4% in the ERP group had horizontal/descending ST slope, while 8% had ST elevation ≥ 2 ms. No arrhythmia or SCD were reported during 1-year follow-up in both groups. Regression analysis showed that male gender, Sokolow-Lyon criteria and short QTc were significant independent predictors of ERP, P value < 0.05. CONCLUSIONS: In outpatient-based Egyptian cohort, the prevalence of ERP was 6.7%, mostly the inferolateral pattern. Our ERP subjects had low-risk clinical and ECG criteria for malignant ERP. Further epidemiological studies are needed to explore the natural history of ERP.

17.
Future Med Chem ; 10(22): 2577-2588, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30526035

RESUMO

AIM: There is an urgent need to develop alternative antimicrobial agents and, one of which is via the use of nanotechnology. Green synthetic routes are recently being replaced for nanoparticles preparation. Methods results: Silver-curcumin nanoconjugates (Ag-CurNCs) were prepared in an eco-friendly method. The prepared nanomaterials were characterized and the photostability was studied under the influence of UV irradiation. Results showed that, the conjugation between curcumin and silver in the nanoform improve the photostability of curcumin. Cytotoxicity was studied on different skin cell lines, and antibacterial activity was investigated against Escherichia coli. Results revealed the antibacterial activity of the prepared nanoconjugates (Ag-CurNCs) with minimal toxicity to skin cells. CONCLUSION: Silver nanoparticles improve the photostability and antibacterial activity of curcumin, while curcumin helps in preparing biocompatible silver nanoparticles.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Curcumina/análogos & derivados , Curcumina/farmacologia , Prata/química , Prata/farmacologia , Antibacterianos/síntese química , Antineoplásicos/síntese química , Linhagem Celular , Linhagem Celular Tumoral , Curcumina/síntese química , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Química Verde/métodos , Humanos , Nanopartículas Metálicas/química , Nanoconjugados/química , Neoplasias Cutâneas/tratamento farmacológico
18.
Egypt Heart J ; 70(3): 181-187, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30190644

RESUMO

BACKGROUND AND OBJECTIVES: P-wave dispersion (PWD) and Interatrial block (IAB) are common in heart failure (HF), and could be associated with adverse cardiac events. We aimed to assess the prevalence of PWD and IAB and their relationship with functional status, hospitalization and mortality rate in patients with systolic HF. METHODS: We enrolled 110 HF patients in sinus rhythm & LVEF <50%. Patients had undergone clinical evaluation, 6 min walking test (6MWT), 12-lead electrocardiography (ECG), 24-h Holter ECG & echocardiogram. Hospitalization and mortality rate were followed-up for one year. PWD was defined as the difference between maximum & minimum P-wave duration >40 ms. IAB was defined as maximum P duration >110 ms. Measurements were done by 2 blinded investigators using a caliber, a ruler and a magnifying lens. RESULTS: Mean age was 58.9 ±â€¯9.7 years and 67.3% were males. Prevalence of PWD and IAB was 68.2% and 57.3%, respectively. Patients with PWD showed these features: 84% in NYHA class III or IV HF, 77.4% had LVEF <35%, 78.7% had paroxysmal Atrial Fibrillation (AF) and 89.4% couldn't complete >200 m (m) in 6MWT. Patients with PWD had more hospitalizations (72% vs 28.6%, P value <0.02) and higher 1-year mortality rate (20% vs 8.6%, P value <0.04) than patients without PWD. Likewise, patients with IAB had nearly similar clinical features, hospitalization and mortality as patients with PWD. CONCLUSION: PWD and IAB are prevalent in patients with systolic HF and they are significantly associated with low LVEF, paroxysmal AF, poor functional capacity, hospitalization and mortality rate.

19.
Sci Rep ; 8(1): 7988, 2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29789633

RESUMO

Rational design of binder-free materials with high cyclic stability and high conductivity is a great need for high performance supercapacitors. We demonstrate a facile one-step synthesis method of binder-free MnO@C nanofibers as electrodes for supercapacitor applications. The topology of the fabricated nanofibers was investigated using FESEM and HRTEM. The X-ray photoelectron spectroscopy (XPS) and the X-ray diffraction (XRD) analyses confirm the formation of the MnO structure. The electrospun MnO@C electrodes achieve high specific capacitance of 578 F/g at 1 A/g with an outstanding cycling performance. The electrodes also show 127% capacity increasing after 3000 cycles. An asymmetric supercapacitor composed of activated carbon as the negative electrode and MnO@C as the positive electrode shows an ultrahigh energy density of 35.5 Wh/kg with a power density of 1000 W/kg. The device shows a superior columbic efficiency, cycle life, and capacity retention.

20.
Talanta ; 185: 344-351, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29759210

RESUMO

A strategy for trace-level carbon-based electrochemical sensors is investigated via exploring the interesting properties of BaNb2O6 nanofibers (NFs). Utilizing adsorptive stripping square wave voltammetry (ASSWV), an electrochemical sensing platform was developed based on BaNb2O6 nanofibers-modified carbon paste electrode (CPE) for the sensitive detection of lornoxicam (LOR). Different techniques were used to characterize the fabricated BaNb2O6 perovskite NFs. The obtained data show the feasibility to electro-oxidize LOR and paracetamol (PAR) on the surface of the fabricated sensor. The amount of nanofiber and testing conditions were optimized using response surface methodology and ASSWV technique. The optimized BaNb2O6/CPE sensor exhibits low detection limit of 6.39 × 10-10 mol L-1, even in the presence of the co-formulated drug paracetamol (PAR). The sensor was successfully applied for biological applications.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Compostos de Cálcio/química , Técnicas Eletroquímicas , Nanofibras/química , Óxidos/química , Piroxicam/análogos & derivados , Titânio/química , Carbono/química , Eletrodos , Estrutura Molecular , Tamanho da Partícula , Piroxicam/análise
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