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1.
J Am Chem Soc ; 146(18): 12496-12510, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38630640

RESUMO

Nuclear forward scattering (NFS) is a synchrotron-based technique relying on the recoil-free nuclear resonance effect similar to Mössbauer spectroscopy. In this work, we introduce NFS for in situ and operando measurements during electrocatalytic reactions. The technique enables faster data acquisition and better discrimination of certain iron sites in comparison to Mössbauer spectroscopy. It is directly accessible at various synchrotrons to a broad community of researchers and is applicable to multiple metal isotopes. We demonstrate the power of this technique with the hydrogen evolution mechanism of an immobilized iron porphyrin supported on carbon. Such catalysts are often considered as model systems for iron-nitrogen-carbon (FeNC) catalysts. Using in situ and operando NFS in combination with theoretical predictions of spectroscopic data enables the identification of the intermediate that is formed prior to the rate-determining step. The conclusions on the reaction mechanism can be used for future optimization of immobilized molecular catalysts and metal-nitrogen-carbon (MNC) catalysts.

2.
Chemistry ; 29(10): e202202465, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36301727

RESUMO

For a future hydrogen economy, non-precious metal catalysts for the water splitting reactions are needed that can be implemented on a global scale. Metal-nitrogen-carbon (MNC) catalysts with active sites constituting a metal center with fourfold coordination of nitrogen (MN4 ) show promising performance, but an optimization rooted in structure-property relationships has been hampered by their low structural definition. Porphyrin model complexes are studied to transfer insights from well-defined molecules to MNC systems. This work combines experiment and theory to evaluate the influence of porphyrin substituents on the electronic and electrocatalytic properties of MN4 centers with respect to the hydrogen evolution reaction (HER) in aqueous electrolyte. We found that the choice of substituent affects their utilization on the carbon support and their electrocatalytic performance. We propose an HER mechanism for supported iron porphyrin complexes involving a [FeII (P⋅)]- radical anion intermediate, in which a porphinic nitrogen atom acts as an internal base. While this work focuses on the HER, the limited influence of a simultaneous interaction with the support and an aqueous electrolyte will likely be transferrable to other catalytic applications.

3.
BMC Musculoskelet Disord ; 23(1): 664, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831850

RESUMO

BACKGROUND: Given the role of vitamin B6 on pronociceptive/antinociceptive neurotransmitters balance, metabolic reactions, and inflammation, it is important to clarify the effect of vitamin B6 on pain and psychological disturbance in fibromyalgia (FM). This study aimed to evaluate whether an 80-mg daily dose of vitamin B6 improves pain, disease severity and psychological symptoms of FM compared to a placebo. METHODS: This randomized, double-blinded, placebo-controlled trial was performed on the FM patients whose diagnosis was confirmed by a rheumatologist based on the 2016 American College of Rheumatology (ACR). 90 Patients were randomized to receive either vitamin B6 (80 mg daily) or placebo in a 1:1 ratio, with a permuted block size of 30 stratified by disease severity. Primary outcomes included the Revised Fibromyalgia Impact Questionnaire (FIQR), Hospital Anxiety and Depression Scale (HADS), 12-item short-form health survey (SF-12), and pain visual analog scale (pain-VAS)). The mean differences in outcomes (before and after treatment) were compared between the vitamin B6 and placebo groups using an independent T-test. An ANCOVA model adjusted for baseline outcome value was also provided to compare the outcomes between the two groups. RESULTS: Of 90 eligible patients, 60 patients (31 patients in vitamin B6 and 29 in the placebo group) completed the trial. Overall, the FIQR, pain-VAS, and HADS-anxiety scores improved after treatment in both vitamin B6 and placebo groups; However, there was no statistically significant intergroup difference regarding primary outcomes. ANCOVA model also showed no difference in the treatment effects. CONCLUSIONS: Our results showed no priority for vitamin B6 over placebo in FM patients. Considering the potential ameliorating role of vitamin B6 on pain and psychological symptoms, acknowledgment of vitamin B6 as a relatively safe adjuvant treatment needs larger future studies. TRIAL REGISTRATION: Iranian Registry of Clinical Trials: IRCT20200920048782N2 on 2021/10/04.


Assuntos
Fibromialgia , Método Duplo-Cego , Fibromialgia/diagnóstico , Fibromialgia/tratamento farmacológico , Humanos , Irã (Geográfico) , Dor/tratamento farmacológico , Dor/etiologia , Índice de Gravidade de Doença , Resultado do Tratamento , Vitamina B 6/uso terapêutico
4.
J Synchrotron Radiat ; 28(Pt 4): 1184-1192, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34212883

RESUMO

The IRIXS Spectrograph represents a new design of an ultra-high-resolution resonant inelastic X-ray scattering (RIXS) spectrometer that operates at the Ru L3-edge (2840 eV). First proposed in the field of hard X-rays by Shvyd'ko [(2015), Phys. Rev. A, 91, 053817], the X-ray spectrograph uses a combination of laterally graded multilayer mirrors and collimating/dispersing Ge(111) crystals optics in a novel spectral imaging approach to overcome the energy resolution limitation of a traditional Rowland-type spectrometer [Gretarsson et al. (2020), J. Synchrotron Rad. 27, 538-544]. In combination with a dispersionless nested four-bounce high-resolution monochromator design that utilizes Si(111) and Al2O3(110) crystals, an overall energy resolution better than 35 meV full width at half-maximum has been achieved at the Ru L3-edge, in excellent agreement with ray-tracing simulations.

5.
Virol J ; 18(1): 243, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876176

RESUMO

INTRODUCTION: Coronavirus disease 2019 (COVID-19), a novel disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to millions of deaths worldwide. Kidney transplant recipients (KTRs) are a fragile population due to their immunosuppressed status. However, there are limited studies available comparing this population with the general population regarding clinical symptoms, and laboratory and imaging features as well as disease severity and clinical outcomes. METHODS: A total of 24 KTRs and 40 patients from the general population (control group) were enrolled after applying exclusion criteria. Clinical symptoms, laboratory values, and lung involvement patterns in high-resolution computed tomography (HRCT) were compared between KTRs with COVID-19 and their counterparts from the general population. Moreover, the category of disease severity and adverse outcomes such as intensive care unit (ICU) admission, mechanical ventilation (MV), and mortality rate were also compared between these two groups. RESULTS: Hypertension was significantly higher among KTRs. Dyspnea was significantly more among the control group (P = 0.045). There was no significant difference in the rest of clinical symptoms (P > 0.05). There was no significant difference in CT features as well, except pleural effusion, which was more prevalent in the control group. A lower absolute lymphocytic count (ALC) and platelet count were observed in KTRs. Renal transplant recipients (RTRs) had a higher elevation in creatinine level than their counterparts. The ICU admission, MV, duration of hospital stay, and mortality as adverse outcomes were not significantly different between the KTR and control groups. CONCLUSION: In conclusion, there was no significant difference in the severity and risk of adverse outcomes, including MV, ICU admission, and mortality between KTRs under chronic immunosuppression and the control group.


Assuntos
COVID-19/diagnóstico , Imunossupressores/efeitos adversos , Transplante de Rim/efeitos adversos , Pulmão/diagnóstico por imagem , SARS-CoV-2/isolamento & purificação , Tomografia Computadorizada por Raios X/métodos , Transplantados , Adulto , Idoso , COVID-19/epidemiologia , COVID-19/mortalidade , COVID-19/terapia , Mortalidade Hospitalar , Humanos , Hospedeiro Imunocomprometido , Unidades de Terapia Intensiva , Tempo de Internação , Pessoa de Meia-Idade , Respiração Artificial , Estudos Retrospectivos , SARS-CoV-2/imunologia , Índice de Gravidade de Doença , Resultado do Tratamento
6.
Transpl Infect Dis ; 22(6): e13420, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32681756

RESUMO

BACKGROUND: In late December 2019, a novel coronavirus SARS-CoV-2 started to spread around the world in different populations. Its clinical and laboratory characteristics and outcome in kidney transplant recipients are little known. Therefore, we describe 22 kidney transplant recipients with SARS-CoV-2-induced pneumonia. METHODS: All kidney transplant recipients who referred to the Razi Hospital of Rasht with a diagnosis of SARS-CoV-2 infection from February 20 to 19th of April 2020 have been included in this observational study. RESULTS: We present 22 cases of COVID-19 in kidney transplant recipients (median age 52 years [interquartile range 40.75-62.75 years]) and baseline eGFR 60 (mL/min/1.73 m2 ) (44.75-86.75). Patients complained of cough (72.7%), dyspnea (63.6%), fever (68.2%), and chill (72.7%) with greater prevalence. We decreased the dose of immunosuppression and started stress dose of intravenous hydrocortisone or equivalent oral prednisolone. Each patient received antiviral therapy based on the latest updated version of local protocol at the time of admission. CT scan findings in 90.9% of patients showed bilateral multifocal lesions. Acute kidney injury (AKI) was observed in 12 patients during hospitalization. Six patients died after a median of 12 days from admission (IQR, 1-21). CONCLUSIONS: In this small observational study, we observed high AKI occurrence and mortality rate in kidney transplant recipients with COVID-19.


Assuntos
Injúria Renal Aguda/complicações , COVID-19/diagnóstico , Transplante de Rim , Transplantados , Adulto , COVID-19/complicações , COVID-19/mortalidade , Calafrios/etiologia , Tosse/etiologia , Dispneia/etiologia , Feminino , Febre/etiologia , Hospitalização , Hospitais , Humanos , Hidrocortisona/administração & dosagem , Hospedeiro Imunocomprometido/efeitos dos fármacos , Terapia de Imunossupressão , Imunossupressores/administração & dosagem , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Prednisolona/administração & dosagem , SARS-CoV-2/isolamento & purificação , Tratamento Farmacológico da COVID-19
7.
J Phys Chem A ; 124(39): 7869-7880, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32894948

RESUMO

α-Sb2O3 (senarmontite), ß-Sb2O3 (valentinite), and α-TeO2 (paratellurite) are compounds with pronounced stereochemically active Sb and Te lone pairs. The vibrational and lattice properties of each have been previously studied but often lead to incomplete or unreliable results due to modes being inactive in infrared or Raman spectroscopy. Here, we present a study of the relationship between bonding and lattice dynamics of these compounds. Mössbauer spectroscopy is used to study the structure of Sb in α-Sb2O3 and ß-Sb2O3, whereas the vibrational modes of Sb and Te for each oxide are investigated using nuclear inelastic scattering, and further information on O vibrational modes is obtained using inelastic neutron scattering. Additionally, vibrational frequencies obtained by density functional theory (DFT) calculations are compared with experimental results in order to assess the validity of the utilized functional. Good agreement was found between DFT-calculated and experimental density of phonon states with a 7% scaling factor. The Sb-O-Sb wagging mode of α-Sb2O3 whose frequency was not clear in most previous studies is experimentally observed for the first time at ∼340 cm-1. Softer lattice vibrational modes occur in orthorhombic ß-Sb2O3 compared to cubic α-Sb2O3, indicating that the antimony bonds are weakened upon transforming from the molecular α phase to the layer-chained ß structure. The resulting vibrational entropy increase of 0.45 ± 0.1 kB/Sb2O3 at 880 K accounts for about half of the α-ß transition entropy. The comparison of experimental and theoretical approaches presented here provides a detailed picture of the lattice dynamics in these oxides beyond the zone center and shows that the accuracy of DFT is sufficient for future calculations of similar material structures.

8.
J Ren Nutr ; 27(2): 113-126, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28065453

RESUMO

OBJECTIVE: Delayed graft function (DGF) is an early complication after deceased donor kidney transplantation with significant adverse effects on graft outcomes. Ischemia-reperfusion injury during transplantation is a major cause of DGF. Tissue concentrations of carnitine, an antioxidant and regulator of cellular energy supply, decrease in the kidney following ischemia-reperfusion insult. Based on promising animal data, this study evaluated the possible protective effect of L-carnitine against DGF. DESIGN: This study is a pilot, randomized, double-blind, placebo-controlled clinical trial that was conducted on kidney transplantation patients in kidney transplant ward of Imam Khomeini hospital complex affiliated to Tehran University of Medical Sciences, Tehran, Iran. SUBJECTS: Patients older than 14 years old undergoing their first kidney transplantation from a deceased donor were evaluated for eligibility to take part in this study. Fifty-six patients were randomly assigned to L-carnitine or placebo groups. INTERVENTION: During this trial, 3 g of oral L-carnitine or placebo was administered in 3 divided doses each day for 4 consecutive days starting the day before kidney transplantation (i.e., days -1, 0, 1, and 2). MAIN OUTCOME MEASURE: The need for dialysis within the first week after transplantation, serum creatinine and urine output were assessed daily. After hospital discharge, patients were followed for 3 months regarding organ function. RESULTS: DGF incidence did not differ between the L-carnitine and placebo groups (18.51% vs. 23.8%, respectively; P = .68). Total allograft failure within 3 months after kidney transplantation happened in 6 patients in the placebo and 1 patient in the L-carnitine group (P = .05). CONCLUSION: This study showed no protective effects of oral L-carnitine supplementation against DGF occurrence recipients; however, 3-month graft loss was lower in the L-carnitine supplemented group.


Assuntos
Carnitina/administração & dosagem , Função Retardada do Enxerto/tratamento farmacológico , Rejeição de Enxerto/tratamento farmacológico , Transplante de Rim , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Carnitina/sangue , Função Retardada do Enxerto/sangue , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Rejeição de Enxerto/sangue , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Lipocalina-2/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Diálise Renal , Resultado do Tratamento
10.
Nanotechnology ; 26(7): 075101, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25642737

RESUMO

The targeted delivery of superparamagnetic iron oxide nanoparticles (SPIONs) as a contrast agent may facilitate their accumulation in cancer cells and enhance the sensitivity of MR imaging. In this study, SPIONs coated with dextran (DSPIONs) were conjugated with bombesin (BBN) to produce a targeting contrast agent for detection of breast cancer using MRI. X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer analyses indicated the formation of dextran-coated superparamagnetic iron oxide nanoparticles with an average size of 6.0 ± 0.5 nm. Fourier transform infrared spectroscopy confirmed the conjugation of the BBN with the DSPIONs. A stability study proved the high optical stability of DSPION-BBN in human blood serum. DSPION-BBN biocompatibility was confirmed by cytotoxicity evaluation. A binding study showed the targeting ability of DSPION-BBN to bind to T47D breast cancer cells overexpressing gastrin-releasing peptide (GRP) receptors. T2-weighted and T2*-weighted color map MR images were acquired. The MRI study indicated that the DSPION-BBN possessed good diagnostic ability as a GRP-specific contrast agent, with appropriate signal reduction in T2*-weighted color map MR images in mice with breast tumors.


Assuntos
Bombesina/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Meios de Contraste/química , Compostos Férricos/química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Animais , Linhagem Celular Tumoral , Diagnóstico por Imagem/métodos , Feminino , Peptídeo Liberador de Gastrina/sangue , Humanos , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Neurotransmissores/química , Peptídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Eur J Clin Pharmacol ; 70(9): 1029-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24958564

RESUMO

OBJECTIVE: In this study, data regarding epidemiology, risk factors, pathogenesis and outcome of tenofovir-induced nephrotoxicity will be reviewed, and current and future approaches for prevention will be discussed. METHOD: The data were collected by searching Scopus, PubMed, Medline, Science direct, Clinical trials and Cochrane database systematic reviews. The keywords used as search terms were "Tenofovir", "TDF", "NRTI", "Nephrotoxicity", "Renal failure", "Kidney damage", "HIV" and "AIDS". RESULTS AND CONCLUSION: Several predisposing factors including elevated baseline SCr, concomitant nephrotoxic medications, low body weight, advanced age, tenofovir disoproxil fumarate (TDF) dose and duration of treatment and lower CD4 cell count were identified as risk factors for development of TDF-induced nephrotoxicity. Cellular accumulation through increased entry from the human organic anion transporters and decreased efflux into tubular lumen is main mechanism of nucleotide analogue antiviral induced nephrotoxicity. Renal function assessment and monitoring at baseline and during TDF treatment are the main approach of prevention of TDF-induced nephrotoxicity. Rosiglitazone may be helpful in patients presenting with TDF-induced nephrotoxicity. Pretreatment with melatonin prevented all known histological changes in proximal tubular mitochondira induced by TDF. Use of antioxidants with mitochondria-targeted properties such as MitoQ or Mito-CP may prevent proximal tubular mitochondrial against TDF damage. Vitamin E, ebselen, lipoic acid, plastoquinone, nitroxides, SOD enzyme mimetics, Szeto-Schiller (SS) peptides, and quercetin are other potential agents for prevention of TDF-induced nephrotoxicity. However, data regarding effectiveness of nephroprotective agents against TDF-induced nephrotoxicity are not conclusive. Before extrapolation of the preclinical evidence to clinical practice, these evidence should be confirmed in future human studies.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/efeitos adversos , Nefropatias/induzido quimicamente , Organofosfonatos/efeitos adversos , Inibidores da Transcriptase Reversa/efeitos adversos , Adenina/efeitos adversos , Animais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Incidência , Nefropatias/epidemiologia , Nefropatias/prevenção & controle , Fatores de Risco , Tenofovir
12.
PLoS One ; 18(12): e0273516, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38085723

RESUMO

INTRODUCTION AND AIMS: Phototherapy is the most common treatment modality of neonatal hyperbilirubinemia. We aimed to evaluate the therapeutic effect of oral Ursodeoxycholic Acid (UDCA) on indirect hyperbilirubinemia in term neonates undergoing phototherapy. MATERIALS AND METHODS: This randomized controlled clinical trial was performed on 106 full-term neonates with jaundice who were admitted to the neonatal ward of 17 Shahrivar Hospital in Rasht, Iran. The neonates were randomly assigned to two groups of intervention (10 mg/kg UDCA+phototherapy) and control (phototherapy alone). Total serum bilirubin (TSB) was measured at the time of admission, during first 12, 24, and 48 hours after admission and at the time of discharge. The duration of hospitalization and side effects were also assessed in both groups. IBM SPSS Statistics for Windows, version 20 was used to analyze the data. RESULTS: Results showed that in the intervention group, 28 (52.8%) of neonates were boys with the mean age of 5.1±1.25 days. While, in the control group 29 (54.7%) of them were boys with the mean age of 5.19±2.26 days. Bilirubin levels in both groups decreased significantly after hospitalization (at 12, 24 and 48 hours) (P <0.001). The mean of bilirubin at 12, 24 and 48 hours in the intervention and control groups were 17.1, 13.2, 10.2 mg / dl and 17.1, 14.2 and 11.3 mg / dl, respectively. At the time of discharge, TSB in the former compared to the latter group was significantly reduced (7.74± 1.39 vs. 8.67±1.35) (P = 0.001). In addition, the duration of hospitalization was considerably shorter in the intervention compared to the control group (P = 0.038) and no side effects were observed. CONCLUSIONS: Administering UDCA plus phototherapy reduced TSB and length of hospital stay with proper safety and efficacy. Therefore, it seems that this combination can be an appropriate treatment modality in neonatal hyperbilirubinemia.


Assuntos
Hiperbilirrubinemia Neonatal , Icterícia , Masculino , Recém-Nascido , Humanos , Feminino , Ácido Ursodesoxicólico/efeitos adversos , Hiperbilirrubinemia Neonatal/terapia , Bilirrubina , Fototerapia/métodos
13.
Int J Mol Sci ; 13(5): 5706-5714, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22754325

RESUMO

CdTe film was deposited using the electrophoretic deposition technique onto an ITO glass at various bath temperatures. Four batch film compositions were used by mixing 1 to 4 wt% concentration of CdTe powder with 10 mL of a solution of methanol and toluene. X-ray Diffraction analysis showed that the films exhibited polycrystalline nature of zinc-blende structure with the (111) orientation as the most prominent peak. From the Atomic Force Microscopy, the thickness and surface roughness of the CdTe film increased with the increase of CdTe concentration. The optical energy band gap of film decreased with the increase of CdTe concentration, and with the increase of isothermal bath temperature. The film thickness increased with respect to the increase of CdTe concentration and bath temperature, and following, the numerical expression for the film thickness with respect to these two variables has been established.


Assuntos
Compostos de Cádmio/química , Telúrio/química , Microscopia de Força Atômica , Espectrofotometria , Propriedades de Superfície , Temperatura , Difração de Raios X
14.
Int J Mol Sci ; 12(9): 6320-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22016661

RESUMO

Thin and transparent films of doped cadmium sulfide (CdS) were obtained on commercial glass substrates by Chemical Bath Deposition (CBD) technique. The films were doped with low concentration of Sn, and annealed in air at 300 °C for 45 min. The morphological characterization of the films with different amounts of dopant was made using SEM and EDAX analysis. Optical properties of the films were evaluated by measuring transmittance using the UV-vis spectrophotometer. A comparison of the results revealed that lower concentration of Sn doping improves transmittance of CdS films and makes them suitable for application as window layer of CdTe/CIGS solar cells.


Assuntos
Compostos de Cádmio/química , Membranas Artificiais , Fenômenos Ópticos , Sulfetos/química , Estanho/química , Microscopia Eletrônica de Varredura , Espectrofotometria , Propriedades de Superfície , Difração de Raios X
15.
Int J Mol Sci ; 12(2): 1293-305, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21541059

RESUMO

Two different concentrations of CdCl(2) and (NH(2))(2)CS were used to prepare CdS thin films, to be deposited on glass substrate by chemical bath deposition (CBD) technique. CdCl(2) (0.000312 M and 0.000625 M) was employed as a source of Cd(2+) while (NH(2))(2)CS (0.00125 M and 0.000625 M) for S(2-) at a constant bath temperature of 70 °C. Adhesion of the deposited films was found to be very good for all the solution concentrations of both reagents. The films were air-annealed at a temperature between 200 °C to 360 °C for one hour. The minimum thickness was observed to be 33.6 nm for film annealed at 320 °C. XRD analyses reveal that the films were cubic along with peaks of hexagonal phase for all film samples. The crystallite size of the films decreased from 41.4 nm to 7.4 nm with the increase of annealing temperature for the CdCl(2) (0.000312 M). Optical energy band gap (E(g)), Urbach energy (E(u)) and absorption coefficient (α) have been calculated from the transmission spectral data. These parameters have been discussed as a function of annealing temperature and solution concentration. The best transmission (about 97%) was obtained for the air-annealed films at higher temperature at CdCl(2) (0.000312 M).


Assuntos
Compostos de Cádmio/química , Sulfetos/química
16.
Int J Biol Macromol ; 151: 1250-1258, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31765751

RESUMO

Osmolytes such as sucrose can interact with the proteins. The aim of the present investigation was to characterize how sucrose could affect the structure, thermal stability and the kinetic of proteinase K. UV-vis spectroscopy, fluorescence spectroscopy, circular dichroism, molecular docking, molecular dynamic simulation studies were used to this end. The UV-vis results are represented the intensity enhancement 270 nm due to alteration in the local environment of Tyr and Trp amino acid residues illustrated the tertiary structure changes of proteinase K. The intrinsic fluorescence intensity was decreased regularly with increase the ligand concentration. The secondary structure alterations were revealed an increase in the α-helix content of enzyme. The activity of enzyme was increased in the presence of sucrose. Thus, sucrose is an activator for proteinase K. Molecular docking results show a negative value for the Gibbs free energy of the binding confirming the spontaneous proteinase K-sucrose complexation and in agreement with fluorescence results. On the other hand, the thermal stability of proteinase K was investigated in the presence of sucrose. The obtained results show that sucrose led to increment the stability of enzyme in a concentration dependent manner. These results are confirmed by the molecular dynamic simulation technique.


Assuntos
Endopeptidase K/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Análise Espectral , Sacarose/química , Algoritmos , Endopeptidase K/metabolismo , Estabilidade Enzimática , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Ligação Proteica , Análise Espectral/métodos , Sacarose/metabolismo
17.
J Res Pharm Pract ; 8(2): 45-51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367638

RESUMO

OBJECTIVE: Package inserts (PIs) provide information for the safe and effective use of medication. There is no study on the evaluation of PIs in Iran. The purpose of this study was to evaluate the completeness of PIs supplied with the 100 top-selling medications in Iran. METHODS: This cross-sectional observational study was conducted during 3 weeks in January 2017. One hundred medications were chosen from a list supplied by the Iran Food and Drug Administration (IFDA). The PIs were assessed for the presentation and completeness of quality criteria, which was consisted of two parts. The first part was the criteria required by the IFDA, mentioned in Chapter 16 of the Pharmaceutical Regulations and Instructions provided by the IFDA. The second part of the criteria was defined according to the critical comments of clinical and industrial pharmacists. FINDINGS: Thirty-seven out of 100 medications included no PIs. None of the PIs met all the criteria required by the IFDA. The highest score for completeness was 18 out of 21 (85.7%). Medication name, description, and adverse reaction were mentioned in all PIs. Other items such as patient counseling information (98%), warnings (95.2%), precautions (95.2%), pregnancy/lactation (95%), and storage condition (90.5%) have been mentioned in a high percentage of PIs. CONCLUSION: PIs have improved in recent years in Iran, but there is an absolute need for more accurate and up-to-date information. The IFDA should supervise pharmaceutical companies more strictly in this regard and should revise its regulations requiring PIs to conform to the FDA regulations.

18.
Res Pharm Sci ; 14(6): 504-514, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32038730

RESUMO

Primary graft dysfunction (PGD) and non-function (PNF) happen in 8.7-24.7% and 0.9-7.2% of liver transplant recipients, respectively. These phenomena increase treatment cost and patients' death. This study assessed the effect of L-carnitine supplementation on the incidences of PNF/PGD in liver transplant recipients. This randomized, placebo-controlled, clinical trial was performed on adult liver transplant recipients. Patients took L-carnitine syrup 500 mg three times daily or placebo from the time of including in transplant waiting list until the day of transplant surgery (median 14 days, 1-192 days). Thirty-three patients in L-carnitine and 39 patients in placebo group completed the study. Although not statistically significant, PNF and PGD happened less frequently among recipients in L-carnitine compared with placebo group (3% vs. 12.8% for PNF; 15.2% vs. 30.8% for PGD). Alanine aminotransferase (ALT) and aspartate aminotransferase were lower in L-carnitine group at day 3 after transplantation. ALT declined more significantly within 48 h after transplantation in L-carnitine arm (median 120.50 vs. 79 IU/L; P = 0.03). One-month patients' survival was significantly higher in L-carnitine versus placebo group (97% vs. 74.4%; P = 0.008). The rates of PNF and PGD in L-carnitine group were approximately one-fourth and one-half of placebo group respectively. One-month patients' survival was higher in L-carnitine group.

19.
J Res Pharm Pract ; 7(2): 69-76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050959

RESUMO

OBJECTIVE: Delayed graft function (DGF) is an early complication after kidney transplantation with negative impact on allograft outcomes. This study assessed the effect of delayed initiation of tacrolimus as a nephrotoxic drug, on DGF occurrence and allograft function. METHODS: This randomized, open-label clinical trial was conducted on kidney transplant recipients with the age of at least 14 years who underwent the first kidney transplantation from deceased or living donor. Patients were randomly allocated to immediate (n = 26) or delayed tacrolimus (n = 27) groups. All patients received thymoglobulin as induction therapy and similar maintenance immunosuppression including tacrolimus, mycophenolate, and prednisolone with the difference in the time of initiation of tacrolimus either on the day of transplantation (immediate tacrolimus group) or day 3 after transplant (delayed tacrolimus group). FINDINGS: DGF incidence (46.15% vs. 37.04%; P = 0.501) and duration (9.75 ± 6.41 vs. 8.6 ± 6.16 days; P = 0.675) were not different between the immediate and delayed tacrolimus groups. Estimated creatinine clearance using Cockcroft-Gault equation (63.14 ± 18.81 vs. 58.19 ± 19.42 mL/min in immediate and delayed tacrolimus groups respectively; P = 0.373) and estimated acute rejection-free survival were also comparable between the groups over the 3 months of follow-up. Compared with the immediate group, the delayed tacrolimus group showed higher estimated 3-month grafts' survival (100% vs. 84.27%; P = 0.072). CONCLUSION: Delayed initiation of tacrolimus after kidney transplantation under the umbrella of thymoglobulin induction did not result in either lower incidence or duration of DGF or improved the level of graft function in kidney transplant recipients but non-statistically significant increased 3-month grafts' survival.

20.
J Res Pharm Pract ; 6(1): 31-39, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28331864

RESUMO

OBJECTIVE: This study assessed incidence, severity, and time to occurrence of drug-induced leukopenia/thrombocytopenia within 1st month after kidney transplantation. METHODS: This cross-sectional study was conducted on newly kidney transplant recipients from two hospitals, Iran. Patients with thrombocytopenia due to acute antibody-mediated rejection were excluded from the study. Demographic, clinical, and laboratory data of patients within the 1st month after transplantation were collected. FINDINGS: Of 213 patients, 14.1% and 66.2% experienced leukopenia and thrombocytopenia, respectively. Cytopenia happened more commonly among patients with thymoglobulin-containing regimen (for leukopenia: 24.6% vs. 0%, P < 0.001; for thrombocytopenia 84.4% vs. 41.8%, P < 0.001). Most leukopenia patients experienced Grades 1 and 2 of leukopenia (46.6% and 40% of patients). Most thrombocytopenic patients showed Grade 1 of thrombocytopenia (78.7%). Cumulative dose of thymoglobulin did not differ between patients with and without leukopenia (5.57 ± 1.13 vs. 5.9 ± 1.96 mg/kg; P = 0.613) or with and without thrombocytopenia (5.87 ± 1.86 vs. 5.56 ± 1.38 mg/kg; P = 0.29). Cytopenia were more common among recipients from deceased compared with from living donors (91.3% vs. 8.7% for leukopenia patients, P = 0.001; 69.9% vs. 33.1% for thrombocytopenia, P = 0.02). More patients with kidney from deceased donors received thymoglobulin in their immunosuppressive regimen (82% vs. 37%; P < 0.001). The median time to leukopenia and thrombocytopenia were 3 days and 1 day, respectively. CONCLUSION: Among immunosuppressive and prophylactic antimicrobial agents, thymoglobulin is more related to cytopenia; therefore, thymoglobulin dose reduction is recommended as the first intervention to manage cytopenia without need for reduction of its cumulative dose. The higher prevalence of cytopenia among recipients from deceased donors may be related to the higher use of thymoglobulin in these patients.

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