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1.
Nanomaterials (Basel) ; 13(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38133025

RESUMO

Selenium nanoparticles (Se NPs) have a number of unique properties that determine the use of the resulting nanomaterials in various fields. The focus of this paper is the stabilization of Se NPs with cetyltrimethylammonium chloride (CTAC). Se NPs were obtained by chemical reduction in an aqueous medium. The influence of the concentration of precursors and synthesis conditions on the size of Se NPs and the process of micelle formation was established. Transmission electron microscopy was used to study the morphology of Se NPs. The influence of the pH of the medium and the concentration of ions in the sol on the stability of Se micelles was studied. According to the results of this study, the concentration of positively charged ions has a greater effect on the particle size in the positive Se NPs sol than in the negative Se NPs sol. The potential antibacterial and fungicidal properties of the samples were studied on Escherichia coli, Micrococcus luteus and Mucor. Concentrations of Se NPs stabilized with CTAC with potential bactericidal and fungicidal effects were discovered. Considering the revealed potential antimicrobial activity, the synthesized Se NPs-CTAC molecular complex can be further studied and applied in the development of veterinary drugs, pharmaceuticals, and cosmetics.

2.
Micromachines (Basel) ; 14(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36985101

RESUMO

In this work, CeO2 nanoparticles, as well as CeO2 nanocomposites with plasmonic silver nanoparticles, were synthesized using a simple sol-gel process. The concentration of silver in the composites varied from 0.031-0.25 wt%. Cerium hydroxide dried gel was calcined at temperatures from 125 to 800 °C to obtain CeO2. It was shown that, at an annealing temperature of 650 °C, single-phase CeO2 nanopowders with an average particle size in the range of 10-20 nm can be obtained. The study of acid-base properties showed that with an increase in the calcination temperature from 500 to 650 °C, the concentration of active centers with pKa 9.4 and 6.4 sharply increases. An analysis of the acid-base properties of CeO2-Ag nanocomposites showed that with an increase in the silver concentration, the concentration of centers with pKa 4.1 decreases, and the number of active centers with pKa 7.4 increases. In a model experiment on dye photodegradation, it was shown that the resulting CeO2 and CeO2-Ag nanopowders have photocatalytic activity. CeO2-Ag nanocomposites, regardless of the silver concentration, demonstrated better photocatalytic activity than pure nanosized CeO2.

3.
Molecules ; 26(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918525

RESUMO

The deuterium content modification in an organism has a neuroprotective effect during the hypoxia model, affecting anxiety, memory and stress resistance. The aim of this work was to elucidate the possible mechanisms of the medium D/H composition modification on nerve cells. We studied the effect of an incubation medium with a 50 ppm deuterium content compared to a medium with 150 ppm on: (1) the activity of Wistar rats' hippocampus CA1 field neurons, (2) the level of cultured cerebellar neuron death during glucose deprivation and temperature stress, (3) mitochondrial membrane potential (MMP) and the generation of reactive oxygen species in cultures of cerebellar neurons. The results of the analysis showed that the incubation of hippocampal sections in a medium with a 50 ppm deuterium reduced the amplitude of the pop-spike. The restoration of neuron activity was observed when sections were returned to the incubation medium with a 150 ppm deuterium content. An environment with a 50 ppm deuterium did not significantly affect the level of reactive oxygen species in neuron cultures, while MMP decreased by 16-20%. In experiments with glucose deprivation and temperature stress, the medium with 50 ppm increased the death of neurons. Thus, a short exposure of nerve cells in the medium with 50 ppm deuterium acts as an additional stressful factor, which is possibly associated with the violation of the cell energy balance. The decrease in the mitochondrial membrane potential, which is known to be associated with ATP synthesis, indicates that this effect may be associated with the cell energy imbalance. The decrease in the activity of the CA1 field hippocampal neurons may reflect reversible adaptive changes in the operation of fast-reacting ion channels.


Assuntos
Meios de Cultura/química , Deutério/análise , Fenômenos Eletrofisiológicos , Hidrogênio/análise , Tecido Nervoso/fisiopatologia , Animais , Região CA1 Hipocampal/patologia , Morte Celular , Cerebelo/patologia , Masculino , Neurônios/patologia , Ratos Wistar , Ácido Succínico/análise , Temperatura
4.
Urol Int ; 104(1-2): 106-112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31743924

RESUMO

INTRODUCTION AND OBJECTIVES: Urinary tract infections (UTI) following ureteroscopy (URS) occur in about 4% of patients. Due to the resistant bacterial strains we encounter in our institution, we retrospectively examined whether a double-drug antibiotic prophylactic treatment (APT) can reduce urosepsis after URS. MATERIALS AND METHODS: Between February 2015 and March 2016, we performed 344 URS for stone treatment. Starting from September 2015, we changed the APT. Exclusion criteria included procedures involving percutaneous nephrolithotomy, pediatric or pregnant patients, and patients with preoperative clinical UTI. RESULTS: Fifty-seven patients were excluded. Group 1 (n = 106) were the last to receive the conventional APT (oral ciprofloxacin), while the second group (n = 181) were the first to receive the new -regimen (intravenous gentamycin and ampicillin). A distinct percentage of both groups had a preoperative positive urine culture (29% in group 1 and 19% in group 2). Seven of 9 septic events developed in patients with preoperative positive urine culture (p < 0.001). Patients undergoing retrograde intrarenal surgery were at increased risk for sepsis when treated with conventional APT (p < 0.01). Post-URS sepsis was 7.5% using the conventional APT and 0.5% with the new APT (p < 0.0001). CONCLUSIONS: A distinct number of patients undergoing URS stone treatment have positive preoperative urine cultures. "One size fits all" APT is not sufficient according to our data. A regimen tailored to the local antibiotic resistance of the uropathogens can lower the rate of sepsis.


Assuntos
Antibioticoprofilaxia , Infecção Hospitalar/prevenção & controle , Cálculos Renais/cirurgia , Sepse/prevenção & controle , Ureteroscopia/efeitos adversos , Infecções Urinárias/prevenção & controle , Administração Oral , Adulto , Idoso , Ampicilina/administração & dosagem , Antibacterianos/administração & dosagem , Ciprofloxacina/administração & dosagem , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana , Feminino , Gentamicinas/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Período Pré-Operatório , Estudos Retrospectivos , Fatores de Risco , Sepse/tratamento farmacológico , Infecções Urinárias/tratamento farmacológico
5.
Rambam Maimonides Med J ; 8(4)2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-28914602

RESUMO

OBJECTIVE: The Lumenis® High-power Holmium Laser (120H) has a unique modulated pulse mode, Moses™ technology. Moses technology modulates the laser pulse to separate the water (vapor bubble), then deliver the remaining energy through the bubble. Proprietary laser fibers were designed for the Moses technology. Our aim was to compare stone lithotripsy with and without the Moses technology. METHODS: We designed a questionnaire for the urologist to fill immediately after each ureteroscopy in which the Lumenis 120H was used. We compared procedures with (n=23) and without (n=11) the use of Moses technology. Surgeons ranked the Moses technology in 23 procedures, in comparison to regular lithotripsy (worse, equivalent, better, much better). Laser working time and energy use were collected from the Lumenis 120H log. RESULTS: During 4 months, five urologists used the Lumenis 120H in 34 ureteroscopy procedures (19 kidney stones, 15 ureteral stones; 22 procedures with a flexible ureteroscope, and 12 with a semi-rigid ureteroscope). Three urologists ranked Moses technology as much better or better in 17 procedures. In 2 cases, it was ranked equivalent, and in 4 cases ranking was not done. Overall, laser lithotripsy with Moses technology utilized laser energy in less time to achieve a satisfying stone fragmentation rate of 95.8 mm3/min versus 58.1 mm3/min, P=0.19. However, this did not reach statistical significance. CONCLUSION: The new Moses laser technology demonstrated good stone fragmentation capabilities when used in everyday clinical practice.

6.
Rambam Maimonides Med J ; 8(4)2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-28777073

RESUMO

Recent developments in diagnostic imaging herald a new approach to diagnosis and management of prostate cancer. Multimodality fusion that combines anatomic with functional imaging data has surpassed either of the two alone. This opens up the possibility to "find and fix" malignancy with greater accuracy than ever before. This is particularly important for prostate cancer because it is the most common male cancer in most developed countries. This article describes technical advances under investigation at our institution and others using multimodality image fusion of magnetic resonance imaging (MRI), transrectal ultrasound (TRUS), and PSMA PET/CT (defined as the combination of prostate-specific membrane antigen [PSMA], positron emission tomography [PET], and computed tomography [CT]) for personalized medicine in the diagnosis and focal therapy of prostate cancer with high-intensity focused ultrasound (HiFUS).

7.
Medicine (Baltimore) ; 86(1): 47-53, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17220755

RESUMO

Emphysematous cystitis is a rare disease characterized by primary infection of the urinary bladder with gas-producing pathogens. There is a paucity of information on this entity in the English-language literature covering the last 45 years, and the clinical picture is poorly outlined. We carried out a comprehensive, retrospective review of the English-language literature from 1986 to 2006, searching for reports describing cases of emphysematous cystitis. The demographic, clinical, laboratory, imaging, and outcome characteristics of every eligible patient were excerpted. In the present report, we describe a typical case of emphysematous cystitis, followed by an analysis of the literature. Of the 53 eligible cases, most were elderly women with diabetes mellitus (62.2%). Classic symptoms of urinary tract infection were present in only 53.3% of cases. Abdominal tenderness and hematuria were noted in 65.6% and 82.3% of cases, respectively. Plain abdominal X-ray was highly sensitive (97.4%), while abdominal computerized tomography was the most sensitive and specific diagnostic tool. A complicated course attributable to emphysematous cystitis was described in 18.8% of cases. The exact mechanism contributing to the formation of gas in such cases is unknown. Various theories have been suggested, including fermentation of glucose in urine, with emphasis on disequilibrium between gas formation and clearance. Emphysematous cystitis has a highly variable presentation and course, with a considerable potential for complications. Further diagnostic imaging is highly recommended in diabetic patients with urinary tract infection who present with abdominal pain and hematuria. Knowledge of this rare entity may lead to early diagnosis and appropriate management.


Assuntos
Cistite/diagnóstico por imagem , Enfisema/diagnóstico por imagem , Idoso , Feminino , Humanos , Radiografia Abdominal , Tomografia Computadorizada por Raios X
8.
Pathophysiology ; 8(4): 255-258, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12100970

RESUMO

We studied the sensitivity of sensorimotor cortex neurons in rabbits to microiontophoretic administration of antibodies against acid fibroblast growth factor (anti-aFGF). Spontaneous activity and reaction of neurons to electrical stimulation of 'feeding centers' in the lateral hypothalamic area (LHA) were recorded. We analyzed impulse activity of 52 neurons in the sensorimotor cortex. It was shown that 14 neurons (25%) reacted to microiontophoresis of anti-aFGF (excitation and inhibition in 9 and 5 neurons, respectively). Microiontophoretic administration of anti-aFGF did not change the reaction (excitation or inhibition) of 27 neurons to electrical stimulation of LHA. Initially, 14 neurons did not response to LHA stimulation. After microiontophoretic administration of anti-aFGF, 6 of 14 neurons displayed pronounced reactions to electrical stimulation of LHA (excitation and inhibition in 2 and 4 neurons, respectively). These data suggest that aFGF plays an important physiological role in feeding motivations.

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