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1.
Life (Basel) ; 13(5)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37240772

RESUMO

Streptococcus pneumoniae is a notorious Gram-positive pathogen present asymptomatically in the nasophayrnx of humans. According to the World Health Organization (W.H.O), pneumococcus causes approximately one million deaths yearly. Antibiotic resistance in S. pneumoniae is raising considerable concern around the world. There is an immediate need to address the major issues that have arisen as a result of persistent infections caused by S. pneumoniae. In the present study, subtractive proteomics was used in which the entire proteome of the pathogen consisting of 1947 proteins is effectively decreased to a finite number of possible targets. Various kinds of bioinformatics tools and software were applied for the discovery of novel inhibitors. The CD-HIT analysis revealed 1887 non-redundant sequences from the entire proteome. These non-redundant proteins were submitted to the BLASTp against the human proteome and 1423 proteins were screened as non-homologous. Further, databases of essential genes (DEGG) and J browser identified almost 171 essential proteins. Moreover, non-homologous, essential proteins were subjected in KEGG Pathway Database which shortlisted six unique proteins. In addition, the subcellular localization of these unique proteins was checked and cytoplasmic proteins were chosen for the druggability analysis, which resulted in three proteins, namely DNA binding response regulator (SPD_1085), UDP-N-acetylmuramate-L-alanine Ligase (SPD_1349) and RNA polymerase sigma factor (SPD_0958), which can act as a promising potent drug candidate to limit the toxicity caused by S. pneumoniae. The 3D structures of these proteins were predicted by Swiss Model, utilizing the homology modeling approach. Later, molecular docking by PyRx software 0.8 version was used to screen a library of phytochemicals retrieved from PubChem and ZINC databases and already approved drugs from DrugBank database against novel druggable targets to check their binding affinity with receptor proteins. The top two molecules from each receptor protein were selected based on the binding affinity, RMSD value, and the highest conformation. Finally, the absorption, distribution, metabolism, excretion, and toxicity (ADMET) analyses were carried out by utilizing the SWISS ADME and Protox tools. This research supported the discovery of cost-effective drugs against S. pneumoniae. However, more in vivo/in vitro research should be conducted on these targets to investigate their pharmacological efficacy and their function as efficient inhibitors.

2.
RSC Adv ; 13(2): 844-852, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36686907

RESUMO

A simple, cost-effective, and efficient differential pulse voltammetric (DPV) assay for monitoring spiramycin adipate (SPA) in its dosage forms, urine, and milk samples at an activated glassy carbon electrode (GCE) was developed. GCE was electrochemically activated by anodization at a high positive voltage (2.5 V). The activated glassy carbon electrode (AGCE) was surface characterized, optimized, and utilized for the electrochemical assay of SPA. The electrochemical behavior of the AGCEs was investigated using cyclic voltammetry (CV) which shows a remarkable increase in the anodic peak of SPA in comparison with GCE. This behavior reflects a remarkable increase in the electrocatalytic oxidation of SPA at AGCE. The impacts of various parameters such as scan rate, accumulation time, and pH were investigated. The analytical performance of the activated glassy carbon electrodes was studied utilizing DPV. Under optimum conditions, the oxidation peak current exhibited two linear ranges of 80 nm to 0.8 µM and 0.85-300 µM with a lower limit of detection (LOD) of 20 nM. The developed assay exhibited high sensitivity, excellent repeatability, and good selectivity. Additionally, the developed SPA-sensitive modified GCE was successfully applied for SPA assay in its pharmaceutical dosage form and diluted biological fluids as well, with satisfactory recovery results which correlated well with the results obtained using spectrophotometry.

3.
RSC Adv ; 12(45): 28878-28885, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36320724

RESUMO

The development of new mesoporous frits for reference electrodes to overcome the limitations of cross-contamination and screening effect is essential for many electrochemical measurements. Available frit-based reference electrodes (e.g., mesoporous, microporous) still suffer from cross-contamination and/or errors in electrochemical measurements. In this work, a mesoporous glass-ceramic composite is prepared to mitigate such limitations. Mesoporous glass-ceramic frits were prepared from low-cost materials (i.e., borosilicate and kaolin) at relatively low temperatures (750-850 °C). The prepared glass-ceramic frits were characterized using scanning electron microscopy (SEM), impedance measurements, and nitrogen sorption isotherms. The developed mesoporous glass-ceramic composites are characterized by a high chemical resistance against corrosive materials and a low thermal expansion. Reference electrodes constructed with the developed mesoporous glass-ceramic frits exhibited a low flow rate of 0.002 ± 0.001 to 0.41 ± 0.06 µL h-1 and high potential stability as well as very small potential drift of -2.4 ± 0.2 to -4.9 ± 0.2 µV h-1. Mesoporous glass-ceramic based reference electrodes exhibited average potential variations of 13 ± 3 mV over the concentration range of 1 mM to 0.1 M KCl. This indicates that mesoporous glass-ceramic frit-based reference electrodes exhibited a much lower flow rate compared to available microporous frit-based reference electrodes. Moreover, the developed mesoporous ceramic-based reference electrodes exhibited a 4-15-fold improvement in potential variations and a large improvement in potential stability in comparison with the reported mesoporous-frit-based reference electrodes.

4.
ACS Omega ; 7(38): 34127-34135, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36188318

RESUMO

Glassy carbon electrode (GCE) was electrochemically activated using a repetitive cyclic voltammetric technique to develop an activated glassy carbon electrode (AGCE). The developed AGCE was optimized and utilized for the electrochemical assay of 4-nitrophenol (4-NP) and dopamine (DA). Cyclic voltammetry (CV) was employed to investigate the electrochemical behavior of the AGCE. Compared to the bare GCE, the developed AGCE exhibits a significant increase in redox peak currents of 4-NP and DA, which indicates that the AGCE significantly improves the electrocatalytic reduction of 4-NP and oxidation of DA. The electrochemical signature of the activation process could be directly associated with the formation of oxygen-containing surface functional groups (OxSFGs), which are the main reason for the improved electron transfer ability and the enhancement of the electrocatalytic activity of the AGCE. The effects of various parameters on the voltammetric responses of the AGCE toward 4-NP and DA were studied and optimized, including the pH, scan rate, and accumulation time. Differential pulse voltammetry (DPV) was also utilized to investigate the analytical performance of the AGCE sensing platform. The optimized AGCE exhibited linear responses over the concentration ranges of 0.04-65 µM and 65-370 µM toward 4-NP with a lower limit of detection (LOD) of 0.02 µM (S/N = 3). Additionally, the AGCE exhibited a linear responses over the concentration ranges of 0.02-1.0 and 1.0-100 µM toward DA with a lower limit of detection (LOD) of 0.01 µM (S/N = 3). Moreover, the developed AGCE-based 4-NP and DA sensors are distinguished by their high sensitivity, excellent selectivity, and repeatability. The developed sensors were successfully applied for the determination of 4-NP and DA in real samples with satisfactory recovery results.

5.
J Med Case Rep ; 15(1): 470, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34521468

RESUMO

BACKGROUND: Horseshoe kidney (HK) is one of the most common renal fusion abnormalities, with an incidence of 1:400 in the normal population. However, Wilms tumor (WT) arising in an HK is a rare occurrence. We report the case of a 9-year-old boy who presented with an advanced WT in an HK and also highlight the management challenges in a resource-poor setting such as ours. CASE PRESENTATION: The patient was a 9-year-old Nigerian boy presented to the Pediatrics Outpatient Clinic of the University of Maiduguri Teaching Hospital (UMTH) with a history of progressive abdominal swelling, weight loss, abdominal pain, and cough. Abdominal examination revealed an irregular, firm, and non-tender mass in the right lumbar region. A computed tomography (CT) scan of the abdomen showed a heterogeneously dense mass that was predominantly to the right side of the abdomen and crossed the midline to the left side, where it continued with the relatively normal renal tissue. Chest CT revealed pulmonary metastases. A diagnosis of WT in an HK was made. The patient had a 6-week course of neoadjuvant chemotherapy, and a right nephrectomy and left partial nephrectomy was performed. The final histologic diagnosis of WT was made. Radiotherapy was intended but was not available in our facility, and the parents could not afford referral to another center. CONCLUSIONS: Children with a clinically suspected HK with WT should undergo a careful imaging evaluation such as CT before any surgical intervention. Neoadjuvant chemotherapy to reduce tumor bulk might be a good treatment method to reduce surgical morbidity and aid in complete excision and potential for preserving renal function.


Assuntos
Rim Fundido , Neoplasias Renais , Tumor de Wilms , Criança , Humanos , Rim/diagnóstico por imagem , Rim/cirurgia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Masculino , Nefrectomia , Tumor de Wilms/diagnóstico por imagem , Tumor de Wilms/cirurgia
6.
Nat Commun ; 12(1): 3429, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103514

RESUMO

Neuroscience research in Africa remains sparse. Devising new policies to boost Africa's neuroscience landscape is imperative, but these must be based on accurate data on research outputs which is largely lacking. Such data must reflect the heterogeneity of research environments across the continent's 54 countries. Here, we analyse neuroscience publications affiliated with African institutions between 1996 and 2017. Of 12,326 PubMed indexed publications, 5,219 show clear evidence that the work was performed in Africa and led by African-based researchers - on average ~5 per country and year. From here, we extract information on journals and citations, funding, international coauthorships and techniques used. For reference, we also extract the same metrics from 220 randomly selected publications each from the UK, USA, Australia, Japan and Brazil. Our dataset provides insights into the current state of African neuroscience research in a global context.


Assuntos
Neurociências/tendências , Publicações/tendências , África , Autoria , Internacionalidade , Fator de Impacto de Revistas , Neurociências/economia , Apoio à Pesquisa como Assunto/economia
7.
J Environ Manage ; 288: 112392, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33765578

RESUMO

Meteorological conditions may influence the incidence of many infectious diseases. Coronavirus disease-2019 (COVID-19) is a highly contagious, air-borne, emerging, viral disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). In 2020, the COVID-19 global pandemic affected more than 210 countries and territories worldwide including Saudi Arabia. There are contradictory research papers about the correlation between meteorological parameters and incidence of COVID-19 in some countries worldwide. The current study investigates the impact of outdoor and indoor meteorological conditions on the daily recorded COVID-19 cases in western region (Makkah and Madinah cities) of Saudi Arabia over a period of 8 months from March to October 2020. Reports of the daily confirmed COVID-19 cases from the webpage of Saudi Ministry of Health (MOH) were used. Considering, the incubation period of COVID-19 which ranged from 2 to 14 days, the relationships between daily COVID-19 cases and outdoor meteorological factors (temperature, relative humidity, and wind speed) using a lag time of 10 days are investigated. The results showed that the highest daily COVID-19 cases in Makkah and Madinah were reported during the hottest months of the year (April-July 2020) when outdoor temperature ranged from 26.51 to 40.71 °C in Makkah and of 23.89-41.20 °C in Madinah, respectively. Partial negative correlation was detected between outdoor relative humidity and daily recorded COVID-19 cases. No obvious correlation could be demonstrated between wind speed and daily COVID-19 cases. This indicated that most of SARS-CoV-2 infection occurred in the cool, air-conditioned, dry, and bad-ventilated indoor environment in the investigated cities. These results will help the epidemiologists to understand the correlation between both outdoor and indoor meteorological conditions and SARS-CoV-2 transmissibility. These findings would be also a useful supplement to assist the local healthcare policymakers to implement and apply a specific preventive measures and education programs for controlling of COVID-19 transmission.


Assuntos
COVID-19 , Cidades , Humanos , Pandemias , SARS-CoV-2 , Arábia Saudita
8.
West Afr J Med ; 37(4): 402-406, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32835403

RESUMO

BACKGROUND: Preterm babies have constituted a major constraints on human and material resources due to early mortality and long term disability among survivors. Rates of disability among survivors have increased over the period, with high rates of broncho-pulmonary dysplasia. OBJECTIVE: To determine the survival and management challenges of preterm babies in University of Maiduguri Teaching Hospital, Maiduguri Borno State REUSLTS: Of the 1129 preterm babies managed in the Special Care Baby Unit (SCBU), 714 cases notes were retrieved and analyzed giving a retrieval rate of 63%. There were 256 (35.9%) preterm babies as in-born, while 458 (64.1%) were out-born. Male preterm babies were 372 (52.1%), while female preterm babies were 342 (47.9%); with female to male ratio of 1.08:1. Extreme low birth weight (<1000grams) were 17 (2.3%), very low birth weight (1000-1499 grams) were 288 (40.3%) while low birth weight (1500-2499 grams) were 406 (56.9%). We also documented 3 preterm babies whose weights >2500 grams were large for gestational age weight. Duration of oxygen therapy (p = 0.620), duration of phototherapy (p = 0.474), and EBT (p = 0.466) showed no association with their survival while only duration of incubator care (p = 0.005) demonstrated significant association with outcome. CONCLUSION: The population of preterm babies studied is 32.70% and their survival has remarkably improved. However, this improved survival of preterm babies especially the extreme and very low birth weight categories has posed a big challenge due to limited access to incubator care, use of caffeine and surfactant which might influence the outcome.


Assuntos
Recém-Nascido de Baixo Peso , Feminino , Idade Gestacional , Hospitais de Ensino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Masculino , Nigéria
9.
Anal Chem ; 92(11): 7947-7954, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32383384

RESUMO

Several reports in the literature deal with the modification of glassy carbon electrode (GCE) surface via electropolymerization of some organic monomers, particularly p-aminobenzenesulfonic acid (p-ABSA) and l-cysteine using intensive oxidative conditions, and attributed the improved electrocatalytic activities toward various analytes to the formation of the electropolymerized layer. What is the real cause for this improvement in electrocatalytic activity? Is it because of the electrochemical activation process of GCE or electropolymerization? Combining a set of surface and electrochemical characterization techniques, we first showed that the electrochemical peaks previously assigned in many reports to electropolymerization processes at the surface of GCE correspond to electrochemical activation of the GCE surface. We further demonstrated that the anodization of GCE at high voltage causes activation of its surface and the formation of surface functional groups (SFGs). In fact, those SFGs are found to be the main reason for the enhancement in electrocatalytic activity of the activated GCE (AGCE). The surface features of the modified electrodes were characterized by Raman spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The electrochemical behavior was investigated using cyclic voltammetry (CV). The analytical performance of AGCE toward dopamine (DA) was assessed using differential pulse voltammetry (DPV). As compared to the previously reported dopamine electrochemical sensors assuming such electropolymerization processes, the AGCE showed analytical performance practically similar to that of these sensors. This further confirms that the enhancement in electrocatalytic activity is due to the electrochemical activation of the GCE surface.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117395, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31362184

RESUMO

This work describes the development of highly sensitive as well as simple two spectrofluorimetric methods for the determination of apramycin sulfate. The first method depends on measuring the inherent native fluorescence of the aqueous neutral solution of the drug at 388 nm (λex 335 nm). While the second method mainly based on enhancing the native fluorescence intensity of the drug using sodium dodecyl sulfate (SDS) micellar media by about 4 fold enhancement. The fluorescence intensity - concentration relationship for the two methods was found rectilinear over the concentration range 1.0-100.0 and 0.1-20.0 µg/mL for the first and second method respectively. The limit of detection for method I and II were 0.05 and 0.02 µg/mL respectively. The proposed methods can be effectively connected for the assurance of the medication without impedances from common normal excipients. Furthermore, the two methods were high sensitive enough for the assurance of the drug in spiked milk samples with high percentage recoveries.


Assuntos
Leite/química , Nebramicina/análogos & derivados , Espectrometria de Fluorescência/métodos , Animais , Resíduos de Drogas/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Modelos Lineares , Nebramicina/análise , Reprodutibilidade dos Testes , Drogas Veterinárias/análise
11.
Int J Radiat Biol ; 96(2): 220-227, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31692407

RESUMO

Purpose: The present study was undertaken to evaluate the protective and therapeutic effects of silymarin and mesenchymal stem cells (MSCs) to ameliorate the damage caused by gamma radiation.Materials and methods: MSCs were given by intravenous injection to male rats (1.4 × 107 cells), 1 day next to gamma radiation (4Gy). While, silymarin was administered orally at a dose of 70 mg/kg b. wt., 3 days before irradiation and continued for 21 days post irradiation.Results: After 1 and 3 weeks post-irradiation, the results revealed a significant decline in red blood corpuscles (RBCs), white blood corpuscles (WBCs) and platelets count with rising in serum lipid profile [total lipids (TL), total glycerides (TG), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C) and very low density lipoprotein-cholesterol (VLDL-C) levels] and total bilirubin; while significant decreases in serum total protein and high density lipoprotein-cholesterol (HDL-C) levels were observed. In irradiated animals receiving double treatment with MSCs and silymarin; amelioration of the changes observed in hematological and biochemical parameters when comparing with the irradiated group.Conclusions: Treatment with a radio-protector (such as silymarin) in addition to MSCs transplantation was recommended to protect against gamma radiation injury.


Assuntos
Antioxidantes/farmacologia , Raios gama , Células-Tronco Mesenquimais/citologia , Estresse Oxidativo/efeitos da radiação , Protetores contra Radiação/farmacologia , Silimarina/farmacologia , Administração Oral , Animais , Plaquetas/efeitos da radiação , Células da Medula Óssea/citologia , Eritrócitos/efeitos da radiação , Leucócitos/efeitos da radiação , Masculino , Ratos
12.
BMC Complement Altern Med ; 19(1): 102, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072346

RESUMO

BACKGROUND: Calothamnus quadrifidus R.Br has many traditional uses and there are few reports about its chemical and biological activities. So our aim is to isolate the triterpenoidal compounds from dichloromethane fraction (DCMF) of Calothamnus quadrifidus R.Br leaves and in addition to evaluate the antibacterial activity of the isolated compounds. METHODS: DCMF of C. quadrifidus leaves was subjected to different chromatographic techniques to isolate pure triterpenoidal compounds which were identified using different chemical and spectroscopic techniques. Antibacterial activities of the isolated compounds were evaluated using agar well diffusion method while minimum inhibitory concentration was assessed by microtiter plate assay method. RESULTS: Five compounds were isolated and they were betulinic acid (1), ursolic acid (2), 3-acetyl-23-hydroxy betulinic acid (3), 2,23-dihydroxy betulinic acid (4) and 2,21,23-trihydroxy betulinic acid (5) were isolated from DCMF of C. quadrifidus leaves for the first time. Compounds 4 and 5 showed strong antibacterial activity against S. typhimurium while compound 4, 5 and 3, 4 exhibits moderate effect against E.coli and S. aureus respectively. CONCLUSION: Pure triterpenoidal compounds isolated from C. quadrifidus leaves showed antibacterial activities in different strengths.


Assuntos
Antibacterianos/farmacologia , Myrtaceae/química , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos , Triterpenos/química
13.
J Appl Microbiol ; 125(5): 1321-1332, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30047213

RESUMO

AIMS: To screen the newly recorded alga Grateloupia doryphora in the Egyptian Mediterranean Sea for antimicrobial activity. METHODS AND RESULTS: Algal samples were collected from the Eastern Harbor, Alexandria, Egypt during summer (2016 and 2017). The dry and fresh methanolic, ethanolic and ethyl acetate algal extracts were tested against Bacillus subtilis, Enterococcus faecalis and Staphylococcus aureus as Gram-positive bacteria, Escherichia coli, Pseudomonas aeruginosa as Gram-negative bacteria and one yeast strain Candida albicans. A three-way analysis of variance showed significant differences based on the algal form, type of solvents and microbial species. The fresh methanolic and ethyl acetate extracts had equal effects on the tested pathogens with means of 14·44 and 15·16 respectively. However, the fresh algal extract was more effective on all the tested organisms than the dried material, except for ethyl acetate and ethanol extract on Bacillus subtilis (31 and 23 mm) respectively. In fact, P. aeruginosa was the most susceptible organism to the fresh algal extract, with much higher inhibition zones (30, 27 and 28 mm) for mehanolic, ethyl acetate and ethanolic extracts, respectively, compared with the dried ones. Furthermore, C. albicans was sensitive to the fresh algal extracts only. Compared with the commercial antibiotics piperacillin, rifampicin, cephalexin, metronidazole and fusidic acid tested against the same microbes, the results showed in general lower or comparable inhibition zones than algal extracts. The GC-MS fresh methanolic and ethyl acetate algal extracts revealed the presence of many potent compounds, with palmitic acid and 2-tetradecyloxirane as the common constituents in both extracts. The commercial palmitic acid was tested against the same microbes with successful elimination of all pathogens. CONCLUSIONS: Grateloupia doryphora showed broad spectrum of antimicrobial activity against the tested microbial species in this study. SIGNIFICANCE AND IMPACT OF THE STUDY: The alga can be useful in industry of pharmaceutical products. On the other hand, its usage in this domain can be a suitable solution to its introduction in our coasts.


Assuntos
Anti-Infecciosos/farmacologia , Extratos Vegetais/farmacologia , Rodófitas/química , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Egito
14.
J Laryngol Otol ; 132(4): 323-326, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29444719

RESUMO

BACKGROUND: The relationship between hypertension and epistaxis is controversial and poorly understood. The present research investigated atherosclerosis as a potential risk factor in hypertensive patients with epistaxis. METHODS: A prospective study of 141 hypertensive patients with epistaxis was conducted. The laboratory tests included full blood count, lipid profile and coagulation profile. All patients underwent funduscopic examination of the eye and were classified in terms of four retinopathy grades. RESULTS: There were strong positive correlations between the number of nosebleeds and retinopathy grade and low-density lipoprotein cholesterol level. There were weak correlations between the number of nosebleeds and blood pressure readings and triglycerides levels. Patients with grade III retinopathy, suggesting atherosclerosis, suffered from more frequent nosebleeds than other patients. CONCLUSION: Atherosclerosis is one of the potential risk factors in hypertensive patients with epistaxis. This may have an impact on treatment choices.


Assuntos
Aterosclerose/complicações , Epistaxe/complicações , Epistaxe/etiologia , Hipertensão/complicações , Hipertensão/fisiopatologia , Aterosclerose/epidemiologia , Pressão Sanguínea/fisiologia , Colesterol/análise , Epistaxe/diagnóstico , Epistaxe/epidemiologia , Feminino , Fundo de Olho , Humanos , Hipertensão/epidemiologia , Retinopatia Hipertensiva/classificação , Retinopatia Hipertensiva/diagnóstico , Lipoproteínas LDL/análise , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Triglicerídeos/análise
15.
Analyst ; 142(17): 3241-3249, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28795694

RESUMO

Electrospray ionization mass spectrometry ESI-MS is a powerful technique for the characterization of macromolecules and their noncovalent binding with guest ions. We herein evaluate the feasibility of using ESI-MS as a screening tool for predicting potentiometric selectivities of ionophores. Ion-selective electrodes based on the cyclic peptide, cyclosporin A, were developed, and their potentiometric selectivity pattern was evaluated. Optimized electrodes demonstrated near-Nernstian slopes with micromolar detection limits toward calcium. ESI-MS and ESI-MS/MS were employed to determine the relative association strengths of cyclosporin A with various cations. The observed MS intensities of ion-ionophore complexes correlate favorably with the potentiometric selectivity pattern that was demonstrated by cyclosporin-based electrodes. This correlation was found to hold true for other established ionophores, such as valinomycin and benzo-18-crown-6. Taken together, these experiments demonstrate that mass spectrometry could be used to predict the selectivity patterns of new ionophores for potentiometric and optical ion sensors. Further, this approach could be useful in screening mixtures or libraries of newly-synthesized compounds to identify selective ionophores.

16.
Sultan Qaboos Univ Med J ; 17(1): e38-e42, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28417027

RESUMO

OBJECTIVES: In cases of fetal intolerance to labour, meeting the standard decision-to-delivery time interval (DDI) of ≤30 minutes is challenging. This study aimed to assess DDIs in emergency Caesarean section (CS) cases to identify factors causing DDI delays and the impact of a delayed DDI on perinatal outcomes. METHODS: This repeated cross-sectional study included all emergency CS procedures performed due to acute fetal distress, antepartum haemorrhage or umbilical cord prolapse at the Nizwa Hospital, Nizwa, Oman. Three audit cycles of three months each were conducted between April 2011 and June 2013, including an initial retrospective cycle and two prospective cycles following the implementation of improvement strategies to address factors causing DDI delays. Poor perinatal outcomes were defined as Apgar scores of <7 at five minutes, admission to the Special Care Baby Unit (SCBU) or a stillbirth. RESULTS: In the initial cycle, a DDI of ≤30 minutes was achieved in 23.8% of 84 cases in comparison to 44.6% of 83 cases in the second cycle. In the third cycle, 60.8% of 79 women had a DDI of ≤30 minutes (P <0.001). No significant differences in perinatal outcomes for cases with a DDI of ≤30 minutes versus 31-60 minutes were observed; however, a DDI of >60 minutes was significantly associated with poor neonatal outcomes in terms of increased SCBU admissions and low Apgar scores (P <0.001 each). Factors causing DDI delays included obtaining consent for the CS procedure, a lack of operating theatre availability and moving patients to the operating theatre. CONCLUSION: The identification of factors causing DDI delays may provide opportunities to improve perinatal outcomes.


Assuntos
Cesárea , Tomada de Decisão Clínica , Tempo para o Tratamento , Cesárea/estatística & dados numéricos , Estudos Transversais , Emergências , Feminino , Sofrimento Fetal , Humanos , Recém-Nascido , Omã , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo
17.
J Affect Disord ; 195: 15-20, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26852093

RESUMO

BACKGROUND: A substantial proportion of primary clinic attendees suffer from psychiatric disorders and many of them are neither recognized nor adequately treated by primary clinic physicians. OBJECTIVES: To determine the point prevalence of, and identify risk factors for, depression, anxiety, and somatisation disorder in the primary health clinics in the country. METHOD: The Physical Health Questionnaires (PHQ-SADs), were administered to a randomized sample of 1046 primary clinic attendees in all the five governorates of the country over a 5-month period. The descriptive data were computed with chi-square tests while the association of demographic characteristics with psychiatric disorders was determined with the logistic regression test. RESULTS: 42.7% of the our patients suffered from psychiatric disorders including depressive (22.9%), anxiety (17.7%), and somatization (33.4%) disorder. Comorbidity between the three disorders was found in 20.4% of the sample; 11% had two and 10.4% had all three disorders. The Kuwaiti nationals, female gender, older age group subjects and those with lower level of education were more likely to suffer from psychiatric disorder. LIMITATIONS: The inter-rater reliability may have affected the results as large number of physicians were responsible for administering the questionnaires. Moreover, the study did not include eating and substance-abuse disorders and the findings were limited to detection of somatization, depression, and anxiety disorders. CONCLUSIONS: In order to ensure timely provision of appropriate treatment, the primary care physicians need adequate information on different forms of presentation, and basic front line treatment, of the common mental disorders at the primary care level.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtorno Depressivo/epidemiologia , Atenção Primária à Saúde/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , Idoso , Transtornos de Ansiedade/psicologia , Comorbidade , Transtorno Depressivo/psicologia , Feminino , Humanos , Kuweit/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Transtornos Somatoformes/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Inquéritos e Questionários , Adulto Jovem
18.
Carbohydr Polym ; 134: 687-94, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26428173

RESUMO

Bacterial cellulose (BC) and heparin-modified bacterial cellulose (HBC) were utilized to enhance the biocompatibility of highly thrombogenic PVC-based potassium and calcium membrane electrodes. Three types of membrane electrodes were prepared: (1) conventional PVC electrode (control), (2) PVC-based electrode sandwiched with bacterial cellulose membrane (BC-PVC), and (3) PVC-based electrode sandwiched with heparin-modified bacterial cellulose membrane (HBC-PVC). The potentiometric response characteristics of the modified potassium and calcium membrane electrodes (BC-PVC and HBC-PVC) were compared with those of the control PVC-based potassium and calcium selective electrode, respectively. Response characteristics of the modified membrane electrodes were comparable to the control PVC membrane electrode. The platelet adhesion investigations indicated that (BC) and (HBC) layers are less thrombogenic compared to PVC. Therefore, use of BC or HBC would enable the enhancement of the biocompatibility of PVC-based membrane electrodes for potassium and calcium while practically maintaining the overall electrochemical performance of the PVC sensing film.


Assuntos
Materiais Biocompatíveis/química , Celulose/química , Gluconacetobacter xylinus/química , Heparina/química , Animais , Materiais Biocompatíveis/farmacologia , Eletrodos , Membranas Artificiais , Agregação Plaquetária/efeitos dos fármacos , Potássio/química , Ovinos
19.
Niger J Clin Pract ; 17(2): 154-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24553023

RESUMO

OBJECTIVE: This study determined the prevalence and socio-demographic characteristics of bacterial vaginosis (BV) among pregnant women with abnormal vaginal discharge. STUDY DESIGN: Descriptive cross-sectional study. SETTING: University of Maiduguri Teaching Hospital. MATERIALS AND METHODS: Vaginal swab samples and data on epidemiological risk factors were collected from 400 consecutive pregnant women with complaints of abnormal vaginal discharge. The data was analyzed using the SPSS 16.0 statistical software. Association between variables was compared by using the Chi-square (χ2 ) and Fisher's exact tests while P < 0.05 was considered significant at 95.0% confidence level. RESULT: The prevalence of BV among pregnant women with abnormal vaginal discharge was 17.3%. Age 20-24 years, multigravidity, lack of western education and unemployment were associated with increased prevalence of BV. Yellowish, watery vaginal discharge (P = 0.001) was associated with BV. Dysuria, dyspareunia and lower abdominal tenderness were associated with BV (P = 0.001). Fifty three (77%) of patients had BV during the second trimester compared to 6 (9%) who had it in the 1 st trimester of pregnancy (P = 0.012). CONCLUSION: The high prevalence of BV in this study may necessitate adequate screening of pregnant women with abnormal vaginal discharge in order to give appropriate treatment and avoid complications associated with it.


Assuntos
Complicações Infecciosas na Gravidez/epidemiologia , Vaginose Bacteriana/epidemiologia , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Nigéria/epidemiologia , Gravidez , Prevalência , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
20.
Talanta ; 118: 147-55, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24274282

RESUMO

Novel uranyl selective polymeric membrane electrodes were prepared using three different low-cost and commercially available Cyanex extractants namely, bis(2,4,4-trimethylpentyl) phosphinic acid [L1], bis(2,4,4-trimethylpentyl) monothiophosphinic acid [L2] and bis(2,4,4-trimethylpentyl) dithiophosphinic acid [L3]. Optimization and performance characteristics of the developed Cyanex based polymer membrane electrodes were determined. The influence of membrane composition (e.g., amount and type of ionic sites, as well as type of plasticizer) on potentiometric responses of the prepared membrane electrodes was studied. Optimized Cyanex-based membrane electrodes exhibited Nernstian responses for UO2(2+) ion over wide concentration ranges with fast response times. The optimized membrane electrodes based on L1, L2 and L3 exhibited Nernstian responses towards uranyl ion with slopes of 29.4, 28.0 and 29.3 mV decade(-1), respectively. The optimized membrane electrodes based on L1-L3 showed detection limits of 8.3 × 10(-5), 3.0 × 10(-5) and 3.3 × 10(-6) mol L(-1), respectively. The selectivity studies showed that the optimized membrane electrodes exhibited high selectivity towards UO2(2+) ion over large number of other cations. Membrane electrodes based on L3 exhibited superior potentiometric response characteristics compared to those based on L1 and L2 (e.g., widest linear range and lowest detection limit). The analytical utility of uranyl membrane electrodes formulated with Cyanex extractant L3 was demonstrated by the analysis of uranyl ion in different real samples for nuclear safeguards verification purposes. The results obtained using direct potentiometry and flow-injection methods were compared with those measured using the standard UV-visible and inductively coupled plasma spectroscopic methods.


Assuntos
Eletrodos Seletivos de Íons , Membranas Artificiais , Centrais Nucleares , Compostos Organotiofosforados/química , Polímeros/química , Compostos de Urânio/análise , Análise de Injeção de Fluxo , Concentração de Íons de Hidrogênio , Potenciometria , Espectrofotometria Ultravioleta
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