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1.
Phys Chem Chem Phys ; 26(26): 18102-18112, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38895843

RESUMO

A successful mechanochemical synthesis of a new nanoscale semi-conductive perovskite, La0.25Sr0.75Sn0.4In0.25Ru0.35O3 (LSSIRuO) was achieved through co-doping of SrSnO3. XRD and IR analyses confirmed that the sample crystallized in a pure perovskite GdFeO3 type structure (Pnma space group). Diffuse reflectance measurements revealed a direct band gap of 1.3 eV, which was significantly narrowed compared to that of SrSnO3 (4.1 eV). The investigation of DFT calculations into the sextenary systems La0.25Sr0.75[Sn0.4Ru0.35]In0.25O3 and La0.25Sr0.75[Sn0.5Ru0.25]In0.25O3 has revealed semiconductor behavior, very close to a semiconductor-semi metal transition. Importantly, Arrhenius-type charge transport was confirmed through a temperature-dependent conductivity study of the sample, showing good electrical conductivity of 3.6 S m-1 at 513 K with an activation energy of Ea = 0.19 eV. Furthermore, the compound exhibited ferromagnetic ordering at temperatures lower than 155 K, contrasting the diamagnetic behavior of SrSnO3. The narrower band gap value (1.3 eV) and improved electrical properties of LSSIRuO, in addition to its ferromagnetic characteristics, distinguish it as a promising candidate for applications in optoelectronics, as well as in memory and spintronic devices.

2.
Heliyon ; 10(3): e25585, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38371967

RESUMO

This study explores the deposition of Tin Oxide and Ni-doped SnO2 thin films (NSO) via spray pyrolysis from aqueous solutions. The deposition process was conducted under uniform conditions on two substrates, namely glass and fluorine tin oxide (FTO), with varying Ni percentages. The aim was to evaluate their potential for gas sensing applications. The as-deposited thin films exhibit diverse properties influenced by both Ni content and substrate type. X-Ray Diffraction (XRD) measurements reveal polycrystalline structures characterized by broad SnO2 diffraction lines, with the emergence of a NiO phase, particularly evident at higher Ni content. Notably, thin films deposited on FTO show the appearance of a secondary phase of SnO and enhanced crystallinity. Furthermore, lattice parameters and crystallite size decrease with increasing Ni percentage. The Field Emission Scanning Electron Microscopy (FE-SEM) analysis highlights significant alterations in surface nanostructures based on nickel content and substrate type. Higher nickel concentrations result in the formation of cauliflower-like structures, varying in size and density. This structural divergence significantly impacts the sensitivity of NSO-based NO2 gas sensors. Particularly, thin films with 20 % Ni, especially those deposited on FTO, exhibit optimal configurations for gas sensor applications, display sensitivity of 501 % at 100 ppm for nanocrystalline NSO/FTO compared to 436 % for glass-deposited samples. Our findings highlight the crucial role of Ni content and substrate type in modifying the structural and sensing properties of NSO thin films, for enhanced gas sensing applications.

3.
Int J Artif Organs ; 46(5): 264-273, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37051719

RESUMO

PURPOSE: The present study aimed to investigate for the first time the effects of melatonin (MEL) intake on oxidative stress and cellular damage during intradialytic exercise (IEX). METHODS: Thirteen hemodialysis (HD) patients volunteered to participate in the current randomized crossover trial. Participants performed four HD sessions in four different conditions: (Exercise (EX)-MEL), (EX-Placebo (PLA)), (Control (C)-MEL), and (C-PLA). 3 mg of MEL or PLA were taken 60 min before starting exercise, or at the equivalent time in the C conditions. Blood samples were taken before HD (T0), immediately after the end of IEX (T1), 60 min after IEX (T2), or at the corresponding times in the C conditions to measure free radicals damage, antioxidant biomarkers, as well as biomarkers of muscle and liver damage. RESULTS: Malondialdehyde and Advanced Oxidation Protein Products decreased in (C-MEL) (p < 0.05, d = 2.19; p < 0.01, d = 0.99, respectively) at T2 compared to T0. Catalase and total thiol levels increased in (C-MEL) (p < 0.01, d = 1.51; p < 0.01, d = 1.56, respectively) and in (EX-MEL) (p = 0.01, d = 1.28; p < 0.01, d = 1.52, respectively) at T1 compared to T0. Total bilirubin levels increased in (EX-MEL) and (C-MEL) at T2 compared to T0 (p < 0.001, d = 2.77; p < 0.001, d = 1.36, respectively), but only at T2 compared to T1 in (EX-MEL) (p < 0.001, d = 1.67). In all conditions, uric acid levels decreased at T1 compared to T0 and at T2 compared to T1, while biomarkers of muscle and liver damage remained unchanged. CONCLUSION: This pilot study is the first to show that MEL ingestion, alone or combined with IEX, could improve oxidant-antioxidant balance during HD.


Assuntos
Antioxidantes , Melatonina , Humanos , Antioxidantes/uso terapêutico , Antioxidantes/farmacologia , Melatonina/uso terapêutico , Melatonina/farmacologia , Projetos Piloto , Peroxidação de Lipídeos , Estresse Oxidativo , Diálise Renal/efeitos adversos , Biomarcadores , Poliésteres
4.
Tunis Med ; 100(6): 481-484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36206068

RESUMO

Peritonitis is an important cause of morbidity and technique failure in peritoneal dialysis. Herein, we report peritonitis related to Acinetobacter lwoffi in two patients on peritoneal dialysis. The first case is a 63-year-old patient treated by automated peritoneal dialysis admitted with abdominal pain. The peritoneal effluent White Blood Cells count consisted of 280 cells/mm3. Then culture identified a multisensitive Acinetobacter lwoffi. Treatment with ceftazidime and ciprofloxacin had been started. The control dialysate culture was sterile after three weeks. The second patient is a 59-year-old female admitted because of diffuse abdominal pain and cloudy dialysate. The peritoneal effluent White Blood Cells count consisted of countless leukocytes, with predominantly polynuclear and culture identified Acinetobacter lwoffi. He received intraperitoneal ceftazidim and amikacin for three weeks. The control dialysate was sterile. Acinetobacter lwoffi is a rare cause of peritonitis and it can be treated successfully with early recognition and appropriate antibiotic therapy based on culture instead of catheter removal.


Assuntos
Acinetobacter , Diálise Peritoneal , Peritonite , Dor Abdominal , Amicacina , Antibacterianos/uso terapêutico , Ceftazidima , Ciprofloxacina , Soluções para Diálise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal/efeitos adversos , Peritonite/diagnóstico , Peritonite/tratamento farmacológico , Peritonite/etiologia
5.
Nephrol Ther ; 18(6): 506-511, 2022 Nov.
Artigo em Francês | MEDLINE | ID: mdl-35778263

RESUMO

Leishmaniasis is a zoonosis acquired from the bite of a sandfly that introduces the amastigote forms of leishmania into the bloodstream. It is a frequent infection in the countries of the Mediterranean basin and in Tunisia, where it is rife in an endemo-epidemic mode. However, it is rare after kidney transplantation. It constitutes a challenge due to the diagnostic difficulty, the variability and the polymorphism of the clinical picture in immunocompromised patients. We report seven observations of cutaneous leishmaniasis after kidney transplantation through which we try to identify diagnostic and therapeutic difficulties.


Assuntos
Transplante de Rim , Leishmaniose Cutânea , Humanos , Transplante de Rim/efeitos adversos , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/etiologia , Hospedeiro Imunocomprometido , Tunísia
6.
Tunis Med ; 100(11): 775-781, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37551519

RESUMO

INTRODUCTION: Type1 primary hyperoxaluria is an infrequent autosomal recessive metabolic disease characterized by the accumulation of calcium oxalate in the kidney, which leads to end stage renal disease. In fact, the diagnosis of this disease is mandatory in order to avoid graft loss. AIM: To assess the incidence of primary hyperoxaluria and to develop the diagnostic value of bone marrow infiltration by calcium oxalate in uremic stone former patients. METHODS: This study was conducted on a cohort of stone former patients identified in the south of Tunisia over a period of 18 years. Baseline characteristics were recorded. Clinical and laboratory data were collected on chart review. Secondary forms of hyperoxaluria were excluded. Bone marrow aspirate was performed in uremic patients from this cohort because early hyperoxaluria was suspected. Diagnostic accuracy of this test relating to sensitivity, specificity, positive predictive value and negative predictive value were also calculated. RESULTS: A cohort of 31 patients comprising 17 male patients and 14 female patients were identified. During this time of diagnosis, the patient's ages ranged from 9 to 57 years old and 22 of them (70%) unfortunately died. Bone marrow aspirate was safely done in 16 uremic patients. It was positive in 12 patients and negative in 4 patients. Sensitivity, specificity, positive predictive value and negative predictive value were respectively 85%, 100%, 100% and 50%. CONCLUSION: The bone marrow examination represents both an easy and a worldwide feasible solution for the diagnosis of oxalosis, which affords an early diagnosis.

7.
Pan Afr Med J ; 38: 137, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912307

RESUMO

The treatment of chronic hepatitis C virus (HCV) infection in chronic hemodialysis patients remains an issue of great concern for nephrologists. In 2008 the kidney disease improving global outcomes working group suggested the use of pegylated interferon in end stage kidney disease patients treated by dialysis. Since then, series and some clinical trials on different direct-acting antiviral agents have shown better efficacy and tolerance than interferon-based regimens. Data on the efficacy, tolerance and the right dose of sofosbuvir in this population are still unclear. We report a case of chronic HCV genotype 1b infection in a 47-year-old patient on maintenance hemodialysis successfully treated by a combination of sofosbuvir and ledipasvir for 12 weeks. Evolution was marked by the complete regression of the hepatic cytolysis, a complete and sustained virologic response with HCV viral load undetectable for a 24 months follow-up period. No adverse reaction was found. The treatment of HCV genotype 1 or 4 infection in patients on maintenance hemodialysis is possible with sofosbuvir based regimens with a good efficacy/safety ratio in the absence of current recommended drugs for patients with eGFR<30ml/min/1.73m2. The prescription of sofosbuvir should be encouraged amongst this population in this setting.


Assuntos
Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Fluorenos/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Diálise Renal , Sofosbuvir/administração & dosagem , Antivirais/efeitos adversos , Benzimidazóis/efeitos adversos , Fluorenos/efeitos adversos , Seguimentos , Genótipo , Taxa de Filtração Glomerular , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Sofosbuvir/efeitos adversos , Resposta Viral Sustentada
8.
Saudi J Kidney Dis Transpl ; 32(3): 838-840, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35102927

RESUMO

Peritonitis remains the most common serious complication associated with peritoneal dialysis (PD). The Gram-positive peritonitis with Staphylococcus aureus and coagulase-negative Staphylococcus are the most frequent causes, whereas Gram-positive and Gram-negative species remain less frequent. We report an uncommon case of PD-related peritonitis due to Streptococcus salivarius, known as nonpathogen Gram-positive bacteria of oral flora.


Assuntos
Diálise Peritoneal/efeitos adversos , Peritonite/diagnóstico , Infecções Estafilocócicas/diagnóstico , Streptococcus salivarius/isolamento & purificação , Dor Abdominal/etiologia , Adulto , Antibacterianos/uso terapêutico , Diarreia/etiologia , Humanos , Injeções Intraperitoneais , Masculino , Náusea/etiologia , Peritonite/tratamento farmacológico , Peritonite/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Resultado do Tratamento , Vancomicina/uso terapêutico
9.
Int Urol Nephrol ; 53(3): 553-562, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32965623

RESUMO

PURPOSE: The present study aimed to investigate the effects of melatonin (MEL) intake on systemic inflammation and immune responses during intradialytic exercise. METHODS: Thirteen hemodialysis (HD) patients volunteered to participate in the current randomized-crossover study. Immunological responses were monitored in four HD sessions at different conditions: [Exercise (EX) + MEL], [EX + Placebo (PLA)], [Control (CON) + MEL] and [CON + PLA]. MEL (3 mg) or PLA was ingested 1 h before starting exercise or the equivalent time in CON condition. During all sessions, peripheral blood samples were collected to assess c-reactive protein, complete blood count, and immune cells phenotypes before HD (T0), immediately after exercise (T1) and 1 h after exercise (T2) or at corresponding times in the CON condition. RESULTS: HD therapy induced a significant decrease in natural killer (NK) (p = 0.001, d = 0.85; p < 0.001, d = 1.19, respectively) and CD8+ T-lymphocytes rates (p = 0.001, d = 0.57; p < 0.001, d = 0.75, respectively) at T1 and T2 compared to T0. MEL intake prevented the decrease in NK and CD8+ T-lymphocytes, increased the proportion of CD4+ T-lymphocytes at T1 and T2 compared to T0 (p = 0.002, d = 1.18; p = 0.001, d = 1.04, respectively) and decreased the proportion of CD14++CD16+ Monocytes at T2 compared to T0 (p = 0.02, d = 1.57) in peripheral blood during HD therapy. Similar results were found in [EX + MEL] and [EX + PLA] conditions. CONCLUSION: This pilot study provides the first evidence that MEL intake alone or associated with intradialytic exercise displays potential immunoregulatory and anti-inflammatory effects. The combination of MEL with intradialytic exercise may be an appropriate anti-inflammatory therapy for HD patients.


Assuntos
Antioxidantes/uso terapêutico , Exercício Físico , Imunidade/efeitos dos fármacos , Inflamação/prevenção & controle , Falência Renal Crônica/terapia , Melatonina/uso terapêutico , Diálise Renal , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Inflamação/etiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/imunologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto
10.
Nephrol Ther ; 16(7): 414-419, 2020 Dec.
Artigo em Francês | MEDLINE | ID: mdl-33203612

RESUMO

INTRODUCTION: Urolithiasis in a kidney transplanted patient is an uncommon but complex urological complication. Its potential severity comes from its occurrence on a solitary kidney and on a field of immunosuppression. The aim of our study is to assess the incidence, characteristics and course of urolithiasis in our series. METHODS: A retrospective study was performed. We included kidney transplanted patients between November 2002 and November 2019 and presenting lithiasis during their follow-up. Clinical, biological and radiological data were collected as well as lithiasis disease related data. The management of and patient's evolution were also specified. RESULTS: Seven of 416 kidney transplanted patients developed lithiasis during their follow-up with an incidence of 1.6 %. The mean age at lithiasis diagnosis was 36.5 years [24-55 years], the sex ratio was 1.3. They developed stones after mean follow-up of 67 months [4-168 months]. The stones' size varied from 2 to 18mm. Treatment was alkalisation in 3 cases, extracorporeal lithotripsy in 2 cases, a double J stent in 3 cases and pyelolithotomy in 2 cases. Four patients had multiple treatments. Three patients had 1 residual stone during evolution (7mm average diameter), 1 microlithiasis, 1 lost to follow-up after treatment and only 2 (out of 7) were "stone free". Furthermore, lithiasis didn't damage the graft survival after a median follow-up of 62 months post-treatment. CONCLUSION: Urolithiasis in the kidney transplanted patient requires an adapted multidisciplinary management. Its skill is a challenge for both the nephrologist and urologist.


Assuntos
Transplante de Rim/efeitos adversos , Transplantados , Urolitíase/epidemiologia , Adulto , Feminino , Humanos , Incidência , Litotripsia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents , Tunísia/epidemiologia , Urolitíase/terapia , Adulto Jovem
11.
Pan Afr Med J ; 36: 195, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32952839

RESUMO

INTRODUCTION: the occurrence of pregnancy in patients on chronic haemodialysis is rare. However, given the evolution in dialysis technique, improvement in fertility is possible. The purpose of our study was to report our experience concerning the occurrence of pregnancy in patients on dialysis and to identify factors involved in its success. METHODS: we conducted a retrospective study on 25 spontaneous pregnancies occurred in 19 patients treated with periodical hemodialysis in different hemodialysis centers in the south of Tunisia over a period of 34 years. RESULTS: maternal age at the onset of pregnancy was, on average, 35.6 years [23-44 years] with an average seniority in hemodialysis of 4.22 years [1-17 years]. Seven patients (37%) had residual diuresis (>500 ml/24h). The prescribed weekly number of hours of dialysis was ≥16 hours per week in 7 cases and ≥20 hours in 4 cases. Success of pregnancy (new-born surviving at least 28 days) was estimated at 56%. The median gestational age was 34 weeks of amenorrhea [28-38 WA]. The average neonatal weight was equal to 1970g [1500g-2300g]. Analytical study showed a significant correlation between the increase in the hours of dialysis per week and the success of pregnancy (R=0.59; p=0.002). CONCLUSION: it was noted that with adequate support and in particular, increasing the number of sessions of dialysis, materno-fetal complications can be minimized and the balance risk-benefit can turn the chance for a woman on dyalisis to become pregnant.


Assuntos
Falência Renal Crônica/terapia , Complicações na Gravidez/terapia , Resultado da Gravidez , Diálise Renal/métodos , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , Fatores de Tempo , Tunísia , Adulto Jovem
12.
Pan Afr Med J ; 35: 129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655743

RESUMO

We re-examine the infrequent paradigm of a biweekly dialysis at the start of renal replacement therapy. The current method is to launch hemodialysis among patients using a 'full-dose' posology three times a week. As a matter of fact, recent data has suggested that frequent hemodialysis leads to high mortality at the onset of dialysis. The aim of our study is to show the factors affecting early mortality especially the hemodialysis frequency. We undertook an observational study in the hemodialysis unit of Sfax University Hospital (south Tunisia). We enrolled the incident patients during one year. Baseline demographic and clinical characteristics of patients were noted. The survival status of each patient is observed at 6 months after the onset of hemodialysis. We analyzed the factors associated with mortality, especially the hemodialysis frequency (twice or thrice weekly hemodialysis regimen). We enrolled 88 patients with mean age of 56 ± 18 years old. Thirty patients underwent twice weekly dialysis (Group 1) and 58 patients underwent thrice weekly dialysis (Group 2). The mortality at 6 months was similar in the 2 groups (the rate of death = 30% in group 1 vs 13.8% in group 2, p = 0.07). However, the mortality was lower in the group with preserved residual diuresis (35.3% vs 64.7% in the group without residual diuresis, p = 0.02). The mortality was higher in diabetes patients (64.7% vs 35.5%, p = 0.02). It was concluded that twice or threefold weekly treatment have some considerable similar outcomes on the patients survival (at 6 months).


Assuntos
Nefropatias/terapia , Diálise Renal/métodos , Adulto , Idoso , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/mortalidade , Unidades Hospitalares de Hemodiálise , Humanos , Nefropatias/mortalidade , Pessoa de Meia-Idade , Diálise Renal/efeitos adversos , Fatores de Tempo , Tunísia
13.
BMC Nephrol ; 18(1): 34, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28114891

RESUMO

BACKGROUND: Mediterranean diet is characterized by low to moderate consumption of animal protein and high consumption of fruits, vegetables, bread, beans, nuts, seeds and other cereals. It has been associated with reduced risk of cardiovascular disease. However, it is not suitable for chronic kidney disease because of high potassium intake. DISCUSSION: Tunisia is an emerging Mediterranean country with limited resources, a high prevalence of chronic hemodialysis treatment and high dialysis expenditures. In order to limit dialysis cost, primary and secondary prevention of chronic renal disease are of paramount importance. In addition to drugs, secondary prevention includes diet measures (e.g. salt diet, protein diet). The aims of diet practice in chronic kidney disease are to slow chronic renal failure progression and to prevent its complications like hyperphosphatemia and hyperkaliemiae. A few decades ago, a Tunisian diet was exclusively Mediterranean, and protein consumption was not excessive. However, today, protein consumption is more comparable to western countries. Salt consumption is also excessive. Some Tunisian diets still include food with high potassium intake, which are not suitable for patients with chronic kidney disease. Therefore, the role of the dietician is extremely important to help calculate and create a dietary regimen tailored to each of our patients. Advice about diets should be adapted to both the patient and population habits to improve adherence rate. As such, the purpose of this article is to provide our own experience regarding medical nutrition therapy in patients with chronic kidney disease in Tunisia, with some changes in food habits. Prevention is far better than treatment. In this perspective, dietary measures must be at the core of our intervention.


Assuntos
Hiperpotassemia/prevenção & controle , Hiperfosfatemia/prevenção & controle , Insuficiência Renal Crônica/dietoterapia , Dieta Mediterrânea/efeitos adversos , Proteínas Alimentares , Humanos , Hiperpotassemia/etiologia , Hiperfosfatemia/etiologia , Ferro da Dieta , Fósforo na Dieta , Potássio na Dieta/efeitos adversos , Insuficiência Renal Crônica/complicações , Prevenção Secundária , Cloreto de Sódio na Dieta/efeitos adversos , Tunísia , Vitamina D
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