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1.
Sensors (Basel) ; 23(16)2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37631697

RESUMEN

System stability deterioration in microgrids commonly occurs due to unpredictable faults and equipment malfunctions. Recently, robust control techniques have been used in microgrid systems to address these difficulties. In this paper, for DC-islanded microgrids that have sensors faults, a new passive fault-tolerant control strategy is developed. The suggested approach can be used to maintain system stability in the presence of flaws, such as faulty actuators and sensors, as well as component failures. The suggested control is effective when the fault is never recognized (or when the fault is not being precisely known, and some ambiguity in the fault may be interpreted as uncertainty in the system's dynamics following the fault). The design is built around a derived sufficient condition in the context of linear matrix inequalities (LMIs) and the attractive ellipsoid technique. The ellipsoidal stabilization idea is to bring the state trajectories into a small region including the origin (an ellipsoid with minimum volume) and the trajectories will not leave the ellipsoid for the future time. Finally, computational studies on a DC microgrid system are carried out to assess the effectiveness of the proposed fault-tolerant control approach. When compared with previous studies, the simulation results demonstrate that the proposed control technique can significantly enhance the reliability and efficiency of DC microgrid systems.

2.
Arch Pharm (Weinheim) ; 355(6): e2100327, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35285986

RESUMEN

Two new series of coumarin and benzofuran derivatives were designed, synthesized, and assessed for their in vitro and in vivo antitumor activities against breast cancer. Compounds 8, 9, 14, 15, and 17 exhibited the best antiproliferative activities (IC50 : 0.07-2.94 µM) against the MCF-7 cell line, compared with lapatinib (IC50 : 4.69 µM). Compound 14, with the most potent cytotoxic activity against MCF-7 cells, was capable of enhancing preG1 apoptosis and triggering cell cycle arrest at the G2/M phase. The kinase inhibitory activity of compound 14 against a panel of 22 kinases was examined to reveal multikinase inhibition within -39% to -97%. Furthermore, compound 14 exhibited potent in vivo Ehrlich (mammary adenocarcinoma) tumor regression, positive caspase-3, and negative EGFR immunoreaction, and was capable of elevating the catalase level. The physicochemical properties and pharmacokinetic parameters of compound 14 were investigated in silico for its druglikeness.


Asunto(s)
Antineoplásicos , Benzofuranos , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis , Benzofuranos/química , Benzofuranos/farmacología , Línea Celular Tumoral , Proliferación Celular , Cumarinas/farmacología , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Relación Estructura-Actividad
3.
Molecules ; 27(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35744976

RESUMEN

In this paper, we report on the design and synthesis of a novel series of quinazoline-2,4(1H,3H)-dione derivatives as fluoroquinolone-like inhibitors of bacterial gyrase and DNA topoisomerase IV to identify and develop antimicrobial agents to prevent bacterial resistance problems. Their structures were confirmed using spectroscopic analyses (IR, NMR, and EI-MS). The novel quinazoline-2,4(1H,3H)-dione derivatives were evaluated for their antimicrobial activities against Gram-positive and Gram-negative bacterial strains using the Agar well diffusion method to study the antimicrobial activities and compared them with the standard drugs. Most compounds displayed moderate activity. Among the tested compounds, the most promising compounds 13 and 15 provided broad bioactive spectrum against Gram-positive and Gram-negative strains compared to the standard drugs.


Asunto(s)
Antibacterianos , Antiinfecciosos , Antibacterianos/química , Antiinfecciosos/farmacología , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Quinazolinas/química , Relación Estructura-Actividad
4.
Bioprocess Biosyst Eng ; 44(4): 759-768, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33420818

RESUMEN

Microbial fuel cells (MFCs) have significant interest in the research community due to their ability to generate electricity from biodegradable organic matters. Anode materials and their morphological structures play a crucial role in the formation of electroactive biofilms that enable the direct electron transfer. In this work, modified electrodes with nanomaterials, such as multiwalled carbon nanotubes (MWCNTs), reduced graphene oxide (rGO), Al2O3/rGO or MnO2/MWCNTs nanocomposites were synthesized, characterized and utilized to support the growth of electrochemically active biofilms. The MFC's performance is optimized using anode-respiring strains isolated from biofilm-anode surface, while the adjusted operation is conducted with the consortium of (Enterobacter sp.). Besides the formation of matured biofilm on its surface, MnO2/MWCNTs nanocomposite produced the highest electrical potential outputs (710 mV) combined with the highest power density (372 mW/m2). Thus, a correlation between the anode nanostructured materials and the progression of the electrochemically active biofilms formation is presented, allowing new thoughts for enhancing the MFC's performance for potential applications ranging from wastewater treatment to power sources.


Asunto(s)
Materiales Biocompatibles/química , Fuentes de Energía Bioeléctrica , Electrodos , Nanotubos de Carbono/química , Biopelículas , Electricidad , Transporte de Electrón , Diseño de Equipo , Grafito , Compuestos de Manganeso , Ensayo de Materiales , Nanoestructuras , Óxidos , Purificación del Agua/instrumentación , Difracción de Rayos X
5.
J Cardiothorac Vasc Anesth ; 34(6): 1622-1635, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32276758

RESUMEN

SEPARATION from cardiopulmonary bypass (CPB) after cardiac surgery is a progressive transition from full mechanical circulatory and respiratory support to spontaneous mechanical activity of the lungs and heart. During the separation phase, measurements of cardiac performance with transesophageal echocardiography (TEE) provide the rationale behind the diagnostic and therapeutic decision-making process. In many cases, it is possible to predict a complex separation from CPB, such as when there is known preoperative left or right ventricular dysfunction, bleeding, hypovolemia, vasoplegia, pulmonary hypertension, or owing to technical complications related to the surgery. Prompt diagnosis and therapeutic decisions regarding mechanical or pharmacologic support have to be made within a few minutes. In fact, a complex separation from CPB if not adequately treated leads to a poor outcome in the vast majority of cases. Unfortunately, no specific criteria defining complex separation from CPB and no management guidelines for these patients currently exist. Taking into account the above considerations, the aim of the present review is to describe the most common scenarios associated with a complex CPB separation and to suggest strategies, pharmacologic agents, and para-corporeal mechanical devices that can be adopted to manage patients with complex separation from CPB. The routine management strategies of complex CPB separation of 17 large cardiac centers from 14 countries in 5 continents will also be described.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Cirugía Torácica , Disfunción Ventricular Derecha , Puente Cardiopulmonar/efectos adversos , Ecocardiografía Transesofágica , Humanos
6.
Can J Physiol Pharmacol ; 96(1): 38-44, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28957639

RESUMEN

Cardiovascular diseases (CVD) are the leading cause of death in the diabetic population. Obesity is a serious problem that has been linked with CVD and diabetes via a variety of adipokines. The aims of this study were to evaluate and correlate circulating chemerin, apelin, vaspin, and omentin-1 levels in obese type 2 diabetic Egyptian patients with coronary artery stenosis (CAS), and to assess their usefulness as noninvasive diagnostic biomarkers. Chemerin, apelin, vaspin, and omentin-1 levels were determined by enzyme immunoassay in coronary artery disease (CAD) I patients (45 non-obese, nondiabetic with CAS), CAD II patients (45 obese, diabetic with CAS), and 30 controls. Patients in CAD I and CAD II groups exhibited higher levels of chemerin and apelin together with lower levels of vaspin and omentin-1 than in controls. These alterations were more significant in CAD II than in CAD I patients. Additionally, adipokine levels were individually correlated with each other and with certain biochemical variables. Moreover, chemerin and vaspin levels could differentiate CAD II patients from CAD I and controls. Alterations of these adipokines may play a crucial role in the pathogenesis of CAS in obese type 2 diabetic Egyptian patients. Chemerin and vaspin could be used as markers to support diagnosis of CAS.


Asunto(s)
Apelina/sangre , Quimiocinas/sangre , Estenosis Coronaria/sangre , Citocinas/sangre , Diabetes Mellitus Tipo 2/sangre , Péptidos y Proteínas de Señalización Intercelular/sangre , Lectinas/sangre , Obesidad/sangre , Serpinas/sangre , Anciano , Estenosis Coronaria/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Egipto , Femenino , Proteínas Ligadas a GPI/sangre , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Curva ROC
7.
Andrologia ; 50(6): e13026, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29781510

RESUMEN

Tramadol, one of the most commonly abused drugs in Middle East, impacts spermatogenesis and disturbs reproductive hormones in animal studies. We aimed to investigate tramadol impact on sperm quality and on levels of testosterone, prolactin and gonadotropins, in tramadol abusers (n = 30) to age-matched control (n = 30). Abusers had significantly low percentages of sperm motility, normal forms and vitality compared with control (95% CI -40.7 to -19.3, -13.5 to -9.3 and -31.9 to -9.7 respectively). Hypoandrogenism (95% CI -4.5 to -2.8), hyperprolactinaemia (CI (95%) 4.9 to 9.4) and hypergonadotropinaemia (95% CI 2.9 to 7.2 for FSH and 2.0 to 7.8 for LH) were observed in tramadol abusers vs controls. Smokers (26 of 30), concurrently abusing other drugs (11 of 30) and asymptomatic leucocytospermic (15 of 30) patients subgroups significantly abused tramadol beyond 3 years (p = .02, <.001, = .03 respectively) and in excess >450 mg/day (p = .02, = .01, = .005 respectively). Progressive motility (a + b%) was significantly low in young men <25 years old (p = .03) subgroup. Tramadol abuse is associated with poor sperm quality, hyperprolactinaemia and hypergonadotropic hypogonadism. We recommend semen analysis for tramadol long-intakes, question sperm donors and follow-up studies to prevent and reverse tramadol-induced testicular damage.


Asunto(s)
Analgésicos Opioides/efectos adversos , Hiperprolactinemia/etiología , Hipogonadismo/etiología , Trastornos Relacionados con Opioides/complicaciones , Motilidad Espermática/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Testículo/efectos de los fármacos , Tramadol/efectos adversos , Adolescente , Adulto , Gonadotropinas/metabolismo , Humanos , Masculino , Medio Oriente , Prolactina/metabolismo , Análisis de Semen , Fumar/epidemiología , Testosterona/metabolismo
8.
J Labelled Comp Radiopharm ; 61(6): 501-508, 2018 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-29430688

RESUMEN

Brain imaging is considered one of the most fruitful applications of radioisotope scanning. Rolipram, a selective phospodiesterase-4 inhibitor, has been labeled using [125 I] with chloramine-T (Ch-T) as an oxidizing agent. Factors, such as the amount of substrate, pH, the amount of oxidizing agent, temperature, and the reaction time, have been systematically studied to optimize the iodination process. In addition, bio-distribution studies have indicated that the brain uptake of [125 I]iodorolipram is 7.6 ± 0.33 injected dose/g organ at 10 minutes post-injection, which cleared from the brain with time until it reaches 1.30 ± 0.17% at 1 hour post-injection. Therefore, iodorolipram could be considered as a potential, new selective radiotracer for brain imaging.


Asunto(s)
Encéfalo/diagnóstico por imagen , Radioisótopos de Yodo/química , Inhibidores de Fosfodiesterasa/síntesis química , Radiofármacos/síntesis química , Rolipram/análogos & derivados , Animales , Rayos gamma , Ratones , Inhibidores de Fosfodiesterasa/farmacocinética , Cintigrafía/métodos , Radiofármacos/farmacocinética , Distribución Tisular
10.
Spinal Cord ; 54(10): 785-797, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26882489

RESUMEN

STUDY DESIGN: Adult human olfactory bulb neural stem cells (OBNSCs) were isolated from human patients undergoing craniotomy for tumor resection. They were genetically engineered to overexpresses green fluorescent protein (GFP) to help trace them following engraftment. Spinal cord injury (SCI) was induced in rats using standard laminectomy protocol, and GFP-OBNSC were engrafted into rat model of SCI at day 7 post injury. Three rat groups were used: (i) Control group, (ii) Sham group (injected with cerebrospinal fluid) and treated group (engrafted with OBNSCs). Tissues from different groups were collected weekly up to 2 months. The collected tissues were fixed in 4% paraformaldehyde, processed for paraffin sectioning, immunohistochemically stained for different neuronal and glial markers and examined with bright-field fluorescent microscopy. Restoration of sensory motor functions we assessed on a weekly bases using the BBB score. OBJECTIVES: To assess the therapeutic potential of OBNSCs-GFP and their ability to survive, proliferate, differentiate and to restore lost sensory motor functions following their engraftment in spinal cord injury (SCI). METHODS: GFP-OBNSC were engrafted into a rat model of SCI at day 7 post injury and were followed-up to 8 weeks using behavioral and histochemical methods. RESULTS: All transplanted animals exhibited successful engraftment. The survival rate was about 30% of initially transplanted cells. Twenty-seven percent of the engrafted cells differentiated along the NG2 and O4-positive oligodendrocyte lineage, 16% into MAP2 and ß-tubulin-positive neurons, and 56% into GFAP-positive astrocytes. CONCLUSION: GFP-OBNSCs had survived for >8 weeks after engraftment and were differentiated into neurons, astrocytes and oligodendrocytes, The engrafted cells were distributed throughout gray and white matter of the cord with no evidence of abnormal morphology or any mass formation indicative of tumorigenesis. However, the engrafted cells failed to restore lost sensory and motor functions as evident from behavioral analysis using the BBB score test.


Asunto(s)
Células-Madre Neurales/fisiología , Células-Madre Neurales/trasplante , Bulbo Olfatorio/citología , Traumatismos de la Médula Espinal/cirugía , Animales , Diferenciación Celular/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Locomoción/fisiología , Proteínas del Tejido Nervioso/metabolismo , Desempeño Psicomotor , Ratas , Ratas Wistar , Factores de Tiempo , Transfección
11.
Int J Phytoremediation ; 18(6): 626-33, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26344169

RESUMEN

The objective of this study was to monitor and assess environmental impacts of reclaimed wastewater (RW), used for irrigation of vegetable crops, on soil, crop quality and irrigation equipment. During 2013, effluents of a horizontal sub-surface flow constructed treatment wetland (TW) system, used for tertiary treatment of sanitary wastewater from a small rural municipality located in Eastern Sicily (Italy), were reused by micro-irrigation techniques to irrigate vegetable crops. Monitoring programs, based on in situ and laboratory analyses were performed for assessing possible adverse effects on water-soil-plant systems caused by reclaimed wastewater reuse. In particular, experimental results evidenced that Escherichia coli content found in RW would not present a risk for rotavirus infection following WHO (2006) standards. Irrigated soil was characterized by a certain persistence of microbial contamination and among the studied vegetable crops, lettuce responds better, than zucchini and eggplants, to the irrigation with low quality water, evidencing a bettering of nutraceutical properties and production parameters.


Asunto(s)
Riego Agrícola/métodos , Verduras/química , Aguas Residuales/análisis , Riego Agrícola/instrumentación , Biodegradación Ambiental , Italia , Verduras/crecimiento & desarrollo , Verduras/metabolismo , Verduras/microbiología , Aguas Residuales/microbiología , Microbiología del Agua , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Humedales
12.
Magn Reson Med ; 74(6): 1726-32, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25483611

RESUMEN

PURPOSE: Diffusion-weighted (DW) hyperpolarized (129) Xe morphometry magnetic resonance imaging (MRI) can be used to map regional differences in lung tissue micro-structure. We aimed to generate absolute xenon concentration ([Xe]) and alveolar oxygen partial pressure (pA O2 ) maps by extracting the unrestricted diffusion coefficient (D0 ) of xenon as a morphometric parameter. METHODS: In this proof-of-concept demonstration, morphometry was performed using multi b-value (0, 12, 20, 30 s/cm(2) ) DW hyperpolarized (129) Xe images obtained in four never-smokers and four COPD ex-smokers. Morphometric parameters and D0 maps were computed and the latter used to generate [Xe] and pA O2 maps. Xenon concentration phantoms estimating a range of values mimicking those observed in vivo were also investigated. RESULTS: Xenon D0 was significantly increased (P = 0.035) in COPD (0.14 ± 0.03 cm(2) /s) compared with never-smokers (0.12 ± 0.02 cm(2) /s). COPD ex-smokers also had significantly decreased [Xe] (COPD = 8 ± 7% versus never-smokers = 13 ± 8%, P = 0.012) and increased pA O2 (COPD = 18 ± 3% versus never-smokers = 15 ± 3%, P = 0.009) compared with never-smokers. Phantom measurements showed the expected dependence of D0 on [Xe] over the range of concentrations anticipated in vivo. CONCLUSION: DW hyperpolarized (129) Xe MRI morphometry can be used to simultaneously map [Xe] and pA O2 in addition to providing micro-structural biomarkers of emphysematous destruction in COPD. Phantom measurements of D0 ([Xe]) supported the hypotheses that differences in subjects may reflect differences in functional residual capacity.


Asunto(s)
Oxígeno/metabolismo , Alveolos Pulmonares/metabolismo , Alveolos Pulmonares/patología , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/patología , Xenón/metabolismo , Anciano , Anciano de 80 o más Años , Medios de Contraste/farmacocinética , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Imagen Molecular/métodos , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Distribución Tisular , Isótopos de Xenón/farmacocinética
13.
Water Environ Res ; 87(10): 883-900, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26420074

RESUMEN

This review summarizes the literature pertaining to the occurrence and detection of indicator organisms and pathogens published during 2014. It is organized into the following sections: i) detection and quantification of fecal indicators and waterborne pathogens, ii) microbial source tracking (MST) using genotypic and phenotypic methods, iii) antibiotic resistant bacteria (ARB), iv) live vs. dead cell differentiation methods, and v) next generation sequencing (NGS).

14.
J Phys Ther Sci ; 27(7): 2029-33, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26311920

RESUMEN

[Purpose] The purpose of this study was to evaluate the effect of 4 weeks moderate aerobic exercise on outcome measures of saliva stress hormones and lactate levels in healthy adult volunteers. [Subjects and Methods] Sixteen healthy students with an age range of 15-25 years participated in this study. The participants performed an exercise test of moderate intensity for 4 weeks, three times per week. The exercise was treadmill walking. Saliva concentrations of cortisol, testosterone and lactate dehydrogenase (LDH) were measured before and after the 4 weeks of moderate aerobic training using immunoassay techniques. [Results] After 4 weeks of exercise, there were significant increases in cortisol, free testosterone levels, and LDH activity along with a significant decrease in the ratios between testosterone and cortisol levels. No significant correlations were found among the studied parameters in the resting stage, a result which supports the positive effect of exercise on stress hormones following 4 weeks of training. [Conclusion] The results suggest that four weeks exercise of moderate intensity significantly affects the salivary stress hormones of young healthy volunteers. The data support the importance of salivary stress hormones as potential biological markers especially for older ages. However, more research is required to validate these biological markers which determine the host response to physical activity.

15.
Neurocase ; 20(6): 695-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24090098

RESUMEN

Multiple sclerosis leads to prominent hippocampal atrophy, which is linked to memory deficits. Indeed, 50% of multiple sclerosis patients suffer memory impairment, with negative consequences for quality of life. There are currently no effective memory treatments for multiple sclerosis either pharmacological or behavioral. Aerobic exercise improves memory and promotes hippocampal neurogenesis in nonhuman animals. Here, we investigate the benefits of aerobic exercise in memory-impaired multiple sclerosis patients. Pilot data were collected from two ambulatory, memory-impaired multiple sclerosis participants randomized to non-aerobic (stretching) and aerobic (stationary cycling) conditions. The following baseline/follow-up measurements were taken: high-resolution MRI (neuroanatomical volumes), fMRI (functional connectivity), and memory assessment. Intervention was 30-minute sessions 3 times per week for 3 months. Aerobic exercise resulted in 16.5% increase in hippocampal volume and 53.7% increase in memory, as well as increased hippocampal resting-state functional connectivity. Improvements were specific, with no comparable changes in overall cerebral gray matter (+2.4%), non-hippocampal deep gray matter structures (thalamus, caudate: -4.0%), or in non-memory cognitive functioning (executive functions, processing speed, working memory: changes ranged from -11% to +4%). Non-aerobic exercise resulted in relatively no change in hippocampal volume (2.8%) or memory (0.0%), and no changes in hippocampal functional connectivity. This is the first evidence for aerobic exercise to increase hippocampal volume and connectivity and improve memory in multiple sclerosis. Aerobic exercise represents a cost-effective, widely available, natural, and self-administered treatment with no adverse side effects that may be the first effective memory treatment for multiple sclerosis patients.


Asunto(s)
Terapia por Ejercicio , Hipocampo/patología , Memoria/fisiología , Esclerosis Múltiple/terapia , Adulto , Encéfalo/fisiopatología , Femenino , Hipocampo/fisiopatología , Humanos , Esclerosis Múltiple/patología , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/psicología , Resultado del Tratamiento
16.
Pak J Med Sci ; 30(4): 840-4, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25097528

RESUMEN

OBJECTIVE: This study assessed the osteogenic effect (T-Score) and changes in bone markers in healthy subjects by 12-weeks of aerobic training. METHODS: Total 65 healthy subjects (36 males, 29 females), their age ranged between 30 and 60 years with normal body mass index, were recruited to participate in this study and they were selected among healthy subjects who do not have any metabolic disorders and were not receiving any medication that could affect the bone turnover. Standardized physical examination and collection of serum samples were performed at base line and after 12 weeks of moderate aerobic training to measure bone formation markers (osteocalcin (OC) and bone specific alkaline Phosphatase (BAP) and bone resorption marker Deoxypyridinoline (DPD), and serum calcium. Each subject participated in exercise training program for 12 weeks, three times per week. RESULTS: The results showed that the 12 weeks of moderate aerobic training produced a significant improvement in all bone metabolism indices including Serum bone-specific alkaline phosphatase, serum osteocalcin, serum free Calcium and bone mineral density among all subjects. Conclusion : Moderate intensity of aerobic training exerts significant positive effects on bone formation marker and bone density associated with a significant decrease in the rate of bone resorption that could assist in preventing or decelerating osteoporosis.

17.
ChemistryOpen ; 13(6): e202400070, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38683824

RESUMEN

This study reports the design, synthesis, and antibacterial evaluation of a library of novel polyheterocyclic derivatives featuring a unique fused pyrimidopyridopyrazole moiety. A cyclocondensation reaction between an amino-pyrazolopyridopyrimidine precursor and malonates afforded a series of pyrimidopyridopyrazolopyrimidine derivatives. Further diversification was achieved through nucleophilic cyclocondensation, yielding a collection of complex polyheterocyclic systems encompassing various ring structures. All synthesized compounds were rigorously characterized using spectroscopic techniques and elemental analysis. The antibacterial activity of the newly synthesized compounds was assessed against a panel of Gram-positive and Gram-negative bacteria. Notably, several compounds exhibited promising antibacterial activity, highlighting their potential as leads for the development of novel antibiotics.


Asunto(s)
Antibacterianos , Diseño de Fármacos , Bacterias Gramnegativas , Bacterias Grampositivas , Pruebas de Sensibilidad Microbiana , Pirazoles , Pirimidinas , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Bacterias Gramnegativas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Bacterias Grampositivas/efectos de los fármacos , Pirazoles/química , Pirazoles/farmacología , Pirazoles/síntesis química , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Relación Estructura-Actividad
18.
Environ Technol ; : 1-10, 2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38584434

RESUMEN

The numbers of wastewater treatment plants (WWTP) in Egypt are increasing, yet the general level of pollution associated with wastewater discharge after treatment has not been evaluated. Grey water footprint (GWF) was used to assess the effluent discharges from Zefta WWTP. GWF, before and after treatment, was calculated and followed up to determine its impact on the receiving freshwater body. 150 samples were collected and analysed for BOD5 to determine the optimum operating conditions. Averages values were DO = 2.2, SV30 = 500, SVI = 167, SA = 9.3 d, MLVSS = 2392 mg/L, f/m = 0.16, MLSS in RAS = 7922 mg/L, WAS = 140 m3/d and the HRT = 12 h. The removal efficiency of COD and TSS in the primary settling tank reached 39% and 69%, respectively. Average calculations of removal efficiency percentile reached 90-93%. Average freshwater quantities required to reduce pollutants in the receiving body stream were seasonally determined for Zefta WWTP as 5.3 × 107 m3/year. The average influent BOD5 was 376 mg/L, it was reduced to 47 mg/L in the effluent, wherever the Cmin is 6 mg/L and Cnat is 10 mg/L. Statistical analysis has shown a significant direct relation between ΔWFG,mef and WFG,ref reached 0.952 and a significant inverse relation with Cef -0.982. WFG,T has shown a significant direct relation with Cr 0.974. WFG,T- ref has shown a significant direct relation with Cr as 0.971 and WFG,T as 0.803. It can be concluded that ΔWF is effective in evaluating the efficiency of wastewater treatment and its effect on the quality of receiving water bodies.

19.
J Genet Eng Biotechnol ; 21(1): 92, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37707582

RESUMEN

BACKGROUND: Tecothane (medical grade of polyurethane) is strongly involved in the fabrication of metallic and polymeric-based medical devices (e.g., catheters and stents) as they can withstand cardiac cycle-related forces without deforming or failing, and they can mimic tissue behavior. The main problem is microbial contamination and formation of pathogenic biofilms on such solid surfaces within the human body. Accordingly, our hypothesis is the coating of tecothane outer surfaces with antibacterial agents through the electro-deposition or chemical grafting of anti-biofilm agents onto the stent and catheter surfaces. RESULTS: Tecothane is grafted with itaconic acid for cross-linking the polyethyleneimine (PEI) as the protective-active layer. Accordingly, the grafting of poly-itaconic acid onto the Tecothane was achieved by three different methods: wet-chemical approach, electro-polymerization, or by using plasma treatment. The successful modifications were verified using Fourier Transform Infrared (FTIR) spectroscopy, grafting percentage calculations, electrochemical, and microscopic monitoring of biofilm formation. The grafting efficiency of itaconic acid was over 3.2% (w/w) at 60 â„ƒ after 6 h of the catheter chemical modification. Bio-electrochemical signals of biofilms have been seriously reduced after chemical modification because of the inhibition of biofilm formation (for both Pseudomonas aeruginosa and Staphylococcus aureus) over a period of 9 days. CONCLUSION: Chemical functionalization of the polyurethane materials with the antimicrobial and anti-biofilm agents led to a significant decrease in the formation of pathogenic biofilms. This promising proof-concept will open the door to explore further surface protection with potential anti-biofilm agents providing better and sustainable productions of stents and catheters biomaterials.

20.
Environ Sci Pollut Res Int ; 30(20): 58569-58587, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36988803

RESUMEN

Abamectin (ABM), a naturally fermented product of Streptomyces avermitilis, is applied to pest control in livestock and agriculture fields. The aim of the current study is to evaluate the protective effects of Moringa oleifera leaf ethanolic extract (MOE) on biochemical changes including oxidative stress indices, immune response marker, lipid profiles as well as mRNA expression of immune related genes, and abamectin (ABM, 5% EC) residue levels in Nile tilapia (Oreochromis niloticus) exposed to a sub-lethal concentration (0.5 µg/l) for 28 days. Disturbance in liver and kidney biomarkers was markedly increased in ABM-exposed fish compared to the control group. Malondialdehyde levels in the liver and brain tissues, as well as the activities of glutathione-s-transferase, superoxide dismutase, and glutathione peroxides, all increased significantly in ABM group. Additionally, ABM exposure increased the levels of interleukin 10 beta and growth factor gene expression. On the other hand, fish exposed to ABM had significantly lower serum alkaline phosphatase, creatinine, high-density lipoprotein, glutathione peroxides in brain, glutathione in liver and brain tissues, lysozyme activity, nitric oxide, immunoglobulin M, tumor necrosis factor, and interleukin 1 beta as compared to the control group. The recorded detrimental effects of ABM on tilapia have been overcome by the addition of MOE to the diet (1%) and ameliorating hepato-renal damage and enhancing antioxidant activity, innate immune responses, and upregulating the anti-inflammatory gene expression. Therefore, it could be concluded that MOE dietary supplementation at 1% could be used to counteract the oxidative stress, immune response disruption induced by abamectin exposure in Oreochromis niloticus, and reduce its accumulation in fish tissues.


Asunto(s)
Cíclidos , Moringa oleifera , Animales , Moringa oleifera/metabolismo , Estrés Oxidativo , Antioxidantes/metabolismo , Glutatión/metabolismo , Dieta , Inmunidad Innata , Peróxidos/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/metabolismo , Suplementos Dietéticos , Alimentación Animal/análisis
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