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1.
ACS Omega ; 9(6): 6339-6354, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38371765

RESUMO

Understanding the intermolecular interactions between antibiotic drugs and hemoglobin is crucial in biological systems. The current study aimed to investigate the preparation of chitosan/polysorbate-80/tripolyphosphate (CS-PS/TPP) nanocomposite as a potential drug carrier for Ciprofloxacin-HCl drug (CFX), intended for controlled release formulation and further used to interact with bovine hemoglobin. Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis-differential thermal analysis (TGA-DTA), scanning electron microscopy (SEM), dynamic light scattering (DLS), and X-ray diffraction analyses were used to characterize the CS-PS/TPP nanocomposite and its CFX-loaded nanocomposite. The second series of biophysical properties were performed on the Ciprofloxacin-loaded CS-PS/TPP (NCFX) for interaction with bovine hemoglobin (BHb). The interactions of (CFX and NCFX) with redox protein hemoglobin were investigated for the first time through a series of in vitro experimental techniques to provide comprehensive knowledge of the drug-protein binding interactions. Additionally, the effect of inclusion of PS-80 on the CFX-BHb interaction was also studied at different concentrations using fluorescence spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, and circular dichroism (CD) under physiological conditions. The binding process of CFX and NCFX was spontaneous, and the fluorescence of BHb was quenched due to the static mechanism formation of the (CFX/BHb) and (NCFX/BHb) complexes. Thermodynamic parameters ΔG, ΔH, and ΔS at various temperatures indicate that the hydrogen bonding and van der Waals forces play a major role in the CFX-BHb association.

2.
ACS Omega ; 8(13): 12232-12245, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37033869

RESUMO

Nowadays, the fabrication of 2D metal-organic nanosheets (2D MONs) has entered the research arena fascinating researchers worldwide. However, a lack of efficient and facile methods has remained a bottleneck for the manufacturing of these 2D MONs. Herein, a 2D metal-organic framework (MOF), i.e., 2D Cu-MOF, was synthesized using a facile and convenient stirring method by using 4,4'-trimethylenedipyridine (TMDP) as an organic linker. The as-prepared MOF was characterized in detail and based on single crystal X-ray diffraction analysis, it was established that tangled layers in the 2D Cu-MOF are interconnected to produce thick strands. These tangled layers could be easily separated via ultrasonication-induced liquid phase exfoliation (UILPE) to give the 2D Cu-MON as illustrated through Tyndall light scattering and exhaustive microscopic exploration such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The application of this 2D Cu-MON was assessed in the field of drug delivery revealing exceptional drug loading for the drug lansoprazole (LPZ) by 2D Cu-MONs as well as drug release in the acidic and neutral medium demonstrating that the 2D Cu-MON is an excellent carrier for antiulcer drug delivery. For environmental protection, the application of 2D Cu-MON was also examined toward the removal of various cationic and anionic dyes with excellent selectivity toward cationic dye removal. The plausible mechanism for dye removal indicated the involvement of cation-π and π-π interactions, for the effective adsorption of cationic dyes as well as a increase in the surface area of 2D Cu-MON by UILPE. Remarkably, the high drug loading and dye removal are imputed to the increase in surface area by UILPE. In a nutshell, the developed 2D Cu-MON will prove to be beneficial for application in the field of drug delivery as well as for wastewater treatment.

3.
J Hazard Mater ; 447: 130732, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36641846

RESUMO

Here, the hybrid material of polyaniline/layered double hydroxide@carbonnanotubes (PANI/LDH@CNT) is considered a multifunctional material. Instrumental methods, including FTIR, XRD, TEM, SEM, and TGA/DTA were utilized to characterize PANI/LDH@CNT. The polymerization method created PANI/LDH@CNT as an adsorbent to remove toxic iodine in hexane solution with a capture capacity of 303.20 mg g-1 during 9 h. It is 900 mg g-1 in the vapor phase within 24 h. After three cycles, the PANI/LDH@CNT could be regenerated while maintaining 91.90 % iodine adsorption efficiency. Due to the presence of free amine (-N) groups, OH-, CO2H, and π-π conjugated structures in the PANI/LDH@CNT, it is also explored for efficient iodine uptake. It was demonstrated that the pseudo-first-order (PFO) and Langmuir model had the optimum correlation with the kinetic and isotherm data, respectively. Moreover, the use of PANI/LDH@CNT is not only limited to iodine capture; it can also be utilized as a sensitive sensor that displays a fluorescence "turn-off" response for Mn7+ and Cr6+ ions and a fluorescence "turn-on" response in the case of Al3+ ions. The fluorescence intensity of the PANI/LDH@CNT was turned off in the presence of Mn7+ and Cr6+ because of the fluorescence inner filter effect (IFE) mechanism. In contrast, the fluorescence intensity was turned on in the case of Al3+, relying on the chelation-enhanced fluorescence (CHEF) effect mechanism. Under optimal conditions, the limit of detection (LOD) of 51, 59, and 81 nM for Mn7+, Cr6+, and Al3+, respectively. According to the literature, this is probably the first example based on PANI/LDH@CNT as a multifunctional hybrid material employed as an adsorbent for capturing radioactive iodine and as a chemosensor for detecting heavy metal ions in aqueous solutions.

4.
J Biomol Struct Dyn ; 41(1): 106-124, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821213

RESUMO

The RxAc drug loaded on Tween80-chitosan-TPP nanoparticles (NRxAc) has been characterized and probed by UV-Vis, PXRD, FTIR, DLS and SEM technique. The physicochemical characteristics of NRxAc have been employed and evaluated for formulation of drug, particle size, external morphology, drug content and in vitro drug release. Multi-spectroscopic (i.e. fluorescence, UV-Vis, CD spectroscopy) and molecular docking techniques were also used to study the interaction of BSA with RxAc and NRxAc. RxAc and NRxAc quenched the fluorescence emission of BSA via a static quenching mechanism. The experimental data of Fluorescence demonstrated that the binding constant of RxAc and NRxAc were found around 104 L.mol-1, which suggests moderate binding affinity with BSA via hydrophobic forces. Through the site marker displacement experiments and molecular docking, the probable binding location of RxAc and NRxAc has been suggested in subdomain IB (site III) of BSA. Altogether, the results of present study can provide an important insight and a great deal of helpful information for future design of antiulcer drugs. Hence, The RxAc-loaded chitosan nanoparticles produced might be utilized as a successful tool for developing and using antiulcer drugs.Communicated by Ramaswamy H. Sarma.


Assuntos
Quitosana , Soroalbumina Bovina , Simulação de Acoplamento Molecular , Soroalbumina Bovina/química , Quitosana/metabolismo , Sítios de Ligação , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Ligação Proteica , Termodinâmica , Dicroísmo Circular
5.
Int J Impot Res ; 24(1): 20-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21833008

RESUMO

This study was conducted to determine the preoperative and intraoperative risk factors of ED and the underlying penile vascular abnormalities among patients with penile fracture treated surgically. In all, 180 patients with penile fracture were treated surgically and followed up in one center. None of our patients had ED before the penile trauma and only two of them had risk factors for systemic vascular diseases, such as diabetes mellitus (one patient) and hypertension (one patient). After a mean follow-up of 106 months, 11 patients (6.6%) developed ED, 7 had mild ED and 4 had moderate ED. The main risk factors for subsequent ED were aging, >50 years, and bilateral corporal involvement. Among the 11 patients with ED, color Doppler ultrasonography (CDU) showed normal Doppler indices in 4 (36.4%), veno-occlusive dysfunction in 4 (36.4%) and arterial insufficiency in the remaining 3 (27.2%) patients. CDU assessments from the injured and intact sides were comparable. ED of either a psychological or vascular origin can be encountered as a long-term sequel of surgical treatment of penile fracture. Aging, >50 years, at presentation and bilateral corporal involvement is the main risk factors for subsequent development of ED.


Assuntos
Disfunção Erétil/epidemiologia , Doenças do Pênis/cirurgia , Pênis/irrigação sanguínea , Pênis/lesões , Complicações Pós-Operatórias/epidemiologia , Adolescente , Adulto , Idoso , Envelhecimento , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Pênis/patologia , Pênis/cirurgia , Fatores de Risco , Ultrassonografia Doppler em Cores , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/epidemiologia
6.
J Clin Microbiol ; 47(7): 2226-31, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19439543

RESUMO

Brucella species are highly monomorphic, with minimal genetic variation among species, hindering the development of reliable subtyping tools for epidemiologic and phylogenetic analyses. Our objective was to compare two distinct multiple-locus variable-number tandem-repeat analysis (MLVA) subtyping methods on a collection of 101 Brucella melitensis isolates from sporadic human cases of brucellosis in Egypt (n = 83), Qatar (n = 17), and Libya (n = 1). A gel-based MLVA technique, MLVA-15(IGM), was compared to an automated capillary electrophoresis-based method, MLVA-15(NAU), with each MLVA scheme examining a unique set of variable-number tandem repeats. Both the MLVA(IGM) and MLVA(NAU) methods were highly discriminatory, resolving 99 and 101 distinct genotypes, respectively, and were able to largely separate genotypes from Egypt and Qatar. The MLVA-15(NAU) scheme presented higher strain-to-strain diversity in our test population than that observed with the MLVA-15(IGM) assay. Both schemes were able to genetically correlate some strains originating from the same hospital or region within a country. In addition to comparing the genotyping abilities of these two schemes, we also compared the usability, limitations, and advantages of the two MLVA systems and their applications in the epidemiological genotyping of human B. melitensis strains.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Brucella melitensis/classificação , Brucella melitensis/genética , Brucelose/microbiologia , Impressões Digitais de DNA/métodos , Repetições Minissatélites , Brucella melitensis/isolamento & purificação , Análise por Conglomerados , Humanos , Oriente Médio , Epidemiologia Molecular/métodos , Sensibilidade e Especificidade
8.
JPEN J Parenter Enteral Nutr ; 30(6): 497-502, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17047174

RESUMO

BACKGROUND: Nutrients affect small intestinal protein mass and metabolism, but studies on the effect of nutrients on small intestinal protein degradation are very limited due to a lack of a proper method. The objectives of this study were to establish a method to directly estimate protein degradation in isolated enterocytes from rats and to test the effect of energy substrates on protein degradation. METHODS: Male Sprague-Dawley rats (150-200 g, n>or=8 per treatment) were used. Cell viability, tyrosine release as an indicator of protein degradation, and the effect of osmolarity, 50 mmol/L glucose, 20 mmol/L beta-hydroxybutyrate, 4.7 mmol/L butyrate, and 30 mmol/L glutamine on protein degradation were measured. RESULTS: The average viability of enterocytes at time 30 minutes was 85.8% (range, 81%-94%). Tyrosine release was linear over the course of experiments, indicating constant protein degradation (R2=0.9943; p<.05). Osmolarity, glucose, and glutamine had no effect on protein degradation in isolated enterocytes. Beta-hydroxybutyrate significantly decreased it (-16%; p<.05), whereas butyrate slightly increased it (+5%; p<.05). CONCLUSIONS: A high viability and constant protein degradation indicate a successful establishment of a method to estimate protein degradation in isolated small intestinal enterocytes from rats. The large effect of beta-hydroxybutyrate suggests a potential positive role for ketone bodies to limit the loss of small intestinal protein mass by decreasing protein degradation.


Assuntos
Enterócitos/metabolismo , Intestino Delgado/citologia , Intestino Delgado/metabolismo , Proteínas/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/farmacologia , Análise de Variância , Animais , Sobrevivência Celular , Células Cultivadas , Metabolismo Energético/fisiologia , Glucose/metabolismo , Glucose/farmacologia , Glutamina/metabolismo , Glutamina/farmacologia , Masculino , Concentração Osmolar , Ratos , Ratos Sprague-Dawley , Tirosina/análise , Tirosina/metabolismo
9.
BJU Int ; 92(9): 987-92, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14632861

RESUMO

OBJECTIVE: To evaluate the outcome of patients with continent urinary diversions who had a solitary functioning kidney at the time of surgery. PATIENTS AND METHODS: In all, 62 patients with continent urinary reservoirs and a solitary functioning kidney were reviewed (51 men and 11 women). The indications for surgery were bladder cancer in 54 and a contracted bladder in eight. The surgical procedures included an orthotopic ileal neobladder in 36 patients, a continent cutaneous ileal reservoir in 13 and rectal diversion in 13. Kidneys were evaluated using serum creatinine level, ultrasonography, intravenous urography and other radiological studies. RESULTS: The follow-up was 6-173 months; 44 renal units (71%) remained stable during this period. Serum creatinine was increased in four patients with an orthotopic neobladder, with no evidence of obstruction or reflux, in one with preoperative renal impairment and one with voiding dysfunction, reflux and bacteriuria. Six renal units deteriorated because of uretero-intestinal strictures; of these patients, two were treated endoscopically, two with open ureteric reimplantation, one with conversion from a rectal reservoir to an ileal loop conduit, and one was maintained on JJ stenting. Six patients with a rectal diversion had renal deterioration because of chronic pyelonephritis. CONCLUSIONS: A regular follow-up of renal function is mandatory in patients with a continent urinary diversion. Rectal diversion is associated with a higher risk of renal deterioration (54%) than are orthotopic (28%) and cutaneous reservoirs (8%).


Assuntos
Nefropatias/fisiopatologia , Doenças da Bexiga Urinária/cirurgia , Derivação Urinária/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Nefropatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Resultado do Tratamento , Doenças da Bexiga Urinária/diagnóstico por imagem , Doenças da Bexiga Urinária/fisiopatologia , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/fisiopatologia , Neoplasias da Bexiga Urinária/cirurgia
10.
J Urol ; 164(4): 1340-4, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10992410

RESUMO

PURPOSE: In patients with posterior urethral valves and persistent high serum creatinine irrespective of vesical drainage proximal urinary diversion is done for presumed concomitant ureterovesical junction obstruction. We retrospectively evaluated whether such management is justified. MATERIALS AND METHODS: Between 1982 and 1995 we reviewed the records of all patients with posterior urethral valves and serum creatinine persistently higher than 1.5 mg./dl. Patient characteristics, treatment method and eventual outcome were determined as well as the results of radiological and Whitaker pressure studies done to exclude obstruction at the ureterovesical junction. RESULTS: Of the 48 patients evaluated 28 underwent primary valve ablation, 16 high loop ureterostomy and 4 vesicostomy. After an average of 78 months (range 37 to 135) chronic renal failure developed in 31% and 25% of those treated with and without high loop ureterostomy, respectively. However, in patients who underwent ureterostomy initially there was a significantly higher rate of decreased bladder capacity, urinary incontinence and augmentation cystoplasty. Obstruction at the ureterovesical junction was noted at surgery and after an average of 2 weeks of diversion in 7 (32%) and 1 (5%) of the 22 cases of percutaneous nephrostomy, respectively. However, after an average of 18 months of ureterostomy drainage we noted evidence of obstruction in 2 of the 27 ureterovesical units (7%). Early in our series 15 of 34 patients (44%) underwent ureterostomy. Subsequently, according to a treatment algorithm including percutaneous nephrostomy, only 1 of 14 boys (7%) underwent such diversion. CONCLUSIONS: Based on our findings high loop ureterostomy does not prevent progression to renal insufficiency and is associated with more complications than primary valve ablation or vesicostomy. Unresolved ureterovesical junction obstruction is rare. Before performing formal supravesical diversion short-term percutaneous nephrostomy drainage helps to identify patients who require diversion.


Assuntos
Creatinina/sangue , Nefrostomia Percutânea , Obstrução Ureteral/cirurgia , Uretra/anormalidades , Progressão da Doença , Humanos , Lactente , Nefrostomia Percutânea/efeitos adversos , Insuficiência Renal/etiologia , Insuficiência Renal/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Obstrução Ureteral/etiologia
11.
Urology ; 49(3): 343-6, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9123695

RESUMO

OBJECTIVES: To review our experience with emphysematous pyelonephritis over the past 15 years. METHODS: Twenty patients with emphysematous pyelonephritis were reviewed regarding diagnosis, treatment, and outcome. RESULTS: Women outnumbered men (75% versus 25%), and 80% of patients were diabetic. The left kidney was more frequently affected than the right one (60% versus 35%) and both kidneys were involved in 5%. Obstruction of the corresponding renoureteral unit was found in all the nondiabetic and in half of the diabetic patients. Diagnosis was confirmed by gas in the parenchyma or perinephric space by plain x-ray of the abdomen or computed tomography. Escherichia coli was the most common organism; it was found in 70% of urine cultures. A prompt attempt to control diabetes was made, and intravenous antibiotics were given. Nephrectomy was immediately performed after stabilization of the general condition of the patients. A total of 80% of patients survived the procedures. CONCLUSIONS: For successful management of emphysematous pyelonephritis, appropriate medical treatment should be attempted but immediate nephrectomy should not be delayed.


Assuntos
Enfisema/complicações , Pielonefrite/complicações , Idoso , Enfisema/diagnóstico , Enfisema/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pielonefrite/diagnóstico , Pielonefrite/terapia
12.
J Urol ; 156(3): 878-80, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8709352

RESUMO

PURPOSE: We compared the accuracy of Doppler ultrasonography and intra-arterial digital subtraction angiography for preoperative visualization of the number of renal arteries in potential live kidney donors. MATERIALS AND METHODS: Intra-arterial digital subtraction angiography and Doppler ultrasonography were used to study the renal anatomy of 64 consecutive kidney donors. Doppler studies were performed without knowledge of the angiographic findings. All donors underwent nephrectomy, and the number of renal arteries at nephrectomy was compared with that predicted by intra-arterial digital subtraction angiography and Doppler ultrasonography. RESULTS: One renal artery was found in 53 harvested kidneys, 2 in 10 and 3 in only 1. Analysis of the data revealed sensitivity 96.2% and specificity 100% for intra-arterial digital subtraction angiography versus sensitivity 100% and specificity 60% for Doppler ultrasound. Overall accuracy was 96.8% for angiography versus 93.7% for Doppler ultrasound, compared to 96.2 and 100%, respectively, for single, and 100% and 60%, respectively, for double renal arteries (p < 0.03). Both tests were interpreted as showing double vessels in the case with triple renal arteries. CONCLUSIONS: Although Doppler ultrasonography is accurate in delineation of single renal arteries, its limited ability to identify multiple arteries should make one cautiously optimistic regarding its current use.


Assuntos
Transplante de Rim , Rim/irrigação sanguínea , Rim/diagnóstico por imagem , Doadores de Tecidos , Adulto , Angiografia Digital , Artérias , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia Doppler
13.
Urology ; 44(1): 96-9, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8042267

RESUMO

OBJECTIVES: To study the efficacy of tetracycline sclerotherapy in renal transplant recipients with symptomatic hydroceles. METHODS: A total of 21 patients with symptomatic hydroceles following renal transplantation underwent aspiration of hydrocele and injection of tetracycline hydrochloride. Sclerosant solution was prepared by dissolving 1 g tetracycline hydrochloride powder in 10 mL 1% lidocaine. The amount of sclerosant used depended on the volume of the sac: 5 mL for a sac containing up to 100 mL and 2.5 mL of sclerosant was added for each increase of 100 mL in sac volume. RESULTS: Twelve patients (57%) required only one treatment and 9 patients (43%) had up to 3 injections. The larger the hydrocele, the more treatments were required. The resolution of hydrocele was complete in 12 patients (57%) and partial in 7 (33%) with 2 (10%) failures. Pain at injection was observed in one third of the patients. No major complications (fever, hematoma, infections, abscess, or scrotal necrosis) occurred in any patient. No changes in the structure or size of the testicles were found by ultrasound during an average follow-up period of 35 months. CONCLUSIONS: Tetracycline sclerotherapy is a safe, effective, and economical form of out-patient therapy that can be recommended as primary treatment for hydroceles in patients who have undergone renal transplantation.


Assuntos
Transplante de Rim/efeitos adversos , Escleroterapia , Hidrocele Testicular/terapia , Tetraciclina/uso terapêutico , Adolescente , Adulto , Idoso , Seguimentos , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Sucção , Hidrocele Testicular/etiologia
14.
C R Seances Soc Biol Fil ; 172(1): 208-11, 1978.
Artigo em Francês | MEDLINE | ID: mdl-150896

RESUMO

The identification of an extrinsic cardiac innervation in Protopterus has been reported for the first time. It has been based on histological, histochemical and ultrastructural methods. The heart of Protopterus receives a rich cholinergic parasympathic innervation which ramifies in the atria and the ventricle. The induced fluorescence did'nt permit us to detect any mono-aminergic fibres ; meanwhile this method has enabled us to distinguish a particular type of cells containing catecholamines in the heart.


Assuntos
Sistema de Condução Cardíaco/ultraestrutura , Animais , Peixes , Histocitoquímica
15.
C R Seances Soc Biol Fil ; 170(3): 712-5, 1976 Oct.
Artigo em Francês | MEDLINE | ID: mdl-135635

RESUMO

Contrary to Francis and Davies's assumption according to which the impulse-conducting system of the Homoiothermal Vertebrates is a neomorphic structure, we have been able to identify in the heart of a Poikilothermal (Protopterus) impulse-conducting cells which possess distinctive histological characters.


Assuntos
Peixes/anatomia & histologia , Sistema de Condução Cardíaco/citologia , Animais , Técnicas Histológicas
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