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3.
Nat Commun ; 11(1): 652, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005805

RESUMO

Perovskite-type transition metal (TM) oxides are effective catalysts in oxidation and decomposition reactions. Yet, the effect of compositional variation on catalytic efficacy is not well understood. The present analysis of electronic characteristics of B-site substituted LaCoO3 derivatives via in situ X-ray absorption spectroscopy (XAS) establishes correlations of electronic parameters with reaction rates: TM t2g and eg orbital occupancy yield volcano-type or non-linear correlations with NO oxidation, CO oxidation and N2O decomposition rates. Covalent O 2p-TM 3d interaction, in ultra-high vacuum, is a linear descriptor for reaction rates in NO oxidation and CO oxidation, and for N2O decomposition rates in O2 presence. Covalency crucially determines the ability of the catalytically active sites to interact with surface species during the kinetically relevant step of the reaction. The nature of the kinetically relevant step and of surface species involved lead to the vast effect of XAS measurement conditions on the validity of correlations.

5.
Trop Biomed ; 36(4): 1061-1070, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33597475

RESUMO

There are little information about Th17 cells and cutaneous Leishmaniasis (CL), due to an important effect of Th17 cells on immune response, it is worth to explore the role of Th17 on CL. The purpose of this study was to assess Th17 population in patients with acute vs. chronic CL lesions in comparison with skin samples collected from healthy volunteers in an endemic region of Old World CL. A total of 49 patients with clinical manifestations of chronic (n=16) and acute (n=33) CL lesions were recruited. The clinical diagnosis of CL was confirmed by direct smear or PCR. Biopsy specimens from prelesional skin of non-infectious lesions of 30 healthy individuals were used as control. Tissue sections of 3µm thickness were prepared and used for immunohistochemistry (IHC) analysis with primary antibody specific for Th17 associated antigen (CD161). For IHC, Envision+ (DakoCytomation) system was used and developed by using diaminobenzidine (DakoCytomation). The mean age of 33 patients with acute CL and the mean age of 16 patients with chronic CL were accordingly 45.24±16.43 and 33.56±15.87. In acute and chronic CL the mean (±standard deviation) and median (±interquartile range) were accordingly 2.92±2.21, 2.56±2.9 and 2.1±1.99, 1.54±2.81. In healthy controls the mean (±standard deviation) and median (±interquartile range) were 0.72±0.41 and 0.61±0.58 respectively. With pairwise comparison of acute, chronic and control groups, there were significant difference between acute and control (P value < 0.001), chronic and control (P value = 0.043). The results showed that there was an increasing cellular response of Th17 in both acute and chronic CL patients. Th17 was significantly higher in patients with acute and chronic CL lesions in comparison with healthy control group. However, there was no significant difference between acute and chronic infection concerning to Th17 cells.


Assuntos
Leishmaniose Cutânea/imunologia , Subfamília B de Receptores Semelhantes a Lectina de Células NK/análise , Células Th17/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Tropical Biomedicine ; : 1061-1070, 2019.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-787792

RESUMO

@#There are little information about Th17 cells and cutaneous Leishmaniasis (CL), due to an important effect of Th17 cells on immune response, it is worth to explore the role of Th17 on CL. The purpose of this study was to assess Th17 population in patients with acute vs. chronic CL lesions in comparison with skin samples collected from healthy volunteers in an endemic region of Old World CL. A total of 49 patients with clinical manifestations of chronic (n=16) and acute (n=33) CL lesions were recruited. The clinical diagnosis of CL was confirmed by direct smear or PCR. Biopsy specimens from prelesional skin of non-infectious lesions of 30 healthy individuals were used as control. Tissue sections of 3μm thickness were prepared and used for immunohistochemistry (IHC) analysis with primary antibody specific for Th17 associated antigen (CD161). For IHC, Envision+ (DakoCytomation) system was used and developed by using diaminobenzidine (DakoCytomation). The mean age of 33 patients with acute CL and the mean age of 16 patients with chronic CL were accordingly 45.24±16.43 and 33.56±15.87. In acute and chronic CL the mean (±standard deviation) and median (±interquartile range) were accordingly 2.92±2.21, 2.56±2.9 and 2.1±1.99, 1.54±2.81. In healthy controls the mean (±standard deviation) and median (±interquartile range) were 0.72±0.41 and 0.61±0.58 respectively. With pairwise comparison of acute, chronic and control groups, there were significant difference between acute and control (P value < 0.001), chronic and control (P value = 0.043). The results showed that there was an increasing cellular response of Th17 in both acute and chronic CL patients. Th17 was significantly higher in patients with acute and chronic CL lesions in comparison with healthy control group. However, there was no significant difference between acute and chronic infection concerning to Th17 cells.

8.
Vet Microbiol ; 190: 27-37, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27283853

RESUMO

The present study was conducted on 428 moribund mullet fish samples to isolate and identify the causative agent of a mysterious acute mortality which recently occurred in wild mullets in Iranian waters of Caspian Sea, suspected to be due to viral nervous necrosis (VNN) disease. Disease investigation was carried out employing various diagnostic procedures such as virology, bacteriology, parasitology, haematology, histopathology, IFAT, IHC and nested RT-PCR. Brain and eye samples of affected fishes were collected in sterile conditions and then kept at -80°C for cell culture isolation and nested RT-PCR detection of the causative agent. Other tissue samples were also collected and fixed for histopathology, IHC and EM examinations. CPE was observed in cell cultures at 6days after inoculation. Nine samples were found positive with virological assay. Nested RT-PCR, performed on suspected tissues and CPE positive samples, showed that about 21 tissue samples and all the CPE positive samples were positive for VNN virus (VNNV). IFAT was selected as a confirmatory method for detecting the presence of Betanodavirus antigen, cell culture isolation results and nested RT-PCR findings. Moreover, VNNV particles with 25-30nm in diameter were also visualized in the infected brain and retina. In pathogenicity studies, guppy fishes bathed in VNNV-infected tissue culture (10(-4) TCID50) showed clinical signs similar to naturally infected mullet after 15days post infection (dpi), with mortality rates reaching up to 100% at 30dpi. Affected organ samples as examined by cell culture isolation, IFAT, IHC and histopathology, revealed the presence of VNNV in the guppy fishes. In conclusion, it was confirmed that VNNV was the main causative agent for the disease outbreak in mullet fish in the Caspian Sea, and this is such first official report of VNN disease from Iran.


Assuntos
Doenças dos Peixes/virologia , Nodaviridae/isolamento & purificação , Infecções por Vírus de RNA/virologia , Animais , Linhagem Celular , Doenças dos Peixes/mortalidade , Doenças dos Peixes/patologia , Técnica Indireta de Fluorescência para Anticorpo , Imuno-Histoquímica , Irã (Geográfico) , Microscopia Eletrônica de Transmissão , Nodaviridae/patogenicidade , Nodaviridae/ultraestrutura , Oceanos e Mares , Reação em Cadeia da Polimerase , Infecções por Vírus de RNA/mortalidade , Infecções por Vírus de RNA/patologia , Smegmamorpha , Análise de Sobrevida
9.
Curr Med Mycol ; 1(4): 26-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28681001

RESUMO

BACKGROUND AND PURPOSE: Candida species are the most opportunistic fungi affecting the nails and resulting in onychomycosis. In this study, we identified and evaluated in-vitro susceptibility of the recovered isolates against fluconazole (FLC), voriconazole (VRC), and clotrimazole (CLT) using the Clinical and Laboratory Standards Institute (CLSI) M27-A3 document. MATERIALS AND METHODS: From patients with either clinically or mycologically proven onychomycosis, 97 isolates comprising of seven Candida species were isolated, which were identified by both conventional and molecular techniques such as polymerase chain reaction-restriction fragment length polymorphism. In addition, Candida dubliniensis was confirmed by restriction endonuclease analysis. Antifungal susceptibility of each isolate against the three azoles applied in this study was determined using the CLSI microdilution reference method M27-A3. RESULTS: Candida parapsilosis(C. parapsilosis) was the most frequently isolated species (n=44), followed by C. albicans (n=23), C.tropicalis (n=13), C.glabrata (n=7), C.krusei (n=6), C.guilliermondii (n=3), and C. dubliniensis (n=1). All the isolates were susceptible to CLT. VRC had lower minimum inhibitory concentration (MIC) values for the isolates compared to FLC. Geometric mean MIC values of VRC, FLC, and CLT for C. parapsilosis isolates were 0.07 µg/ml, 0.8 µg/ml, and 0.35 µg/ml, respectively. Collectively, all species exhibited greater susceptibility to VRC in comparison to C. albicans (P≤0.001). CONCLUSION: This study showed that non-albicansCandida species were the most common etiologic agents of non-dermatophyte onychomycosis. The major antifungal agents used in clinics to empirically treat yeast onychomycosis are FLC and CLT. Our data suggested that CLT is a better choice for the treatment of Candida onychomycosis, especially in drug resistant cases.

10.
Med Eng Phys ; 36(10): 1296-304, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25074649

RESUMO

An anatomically detailed eighteen-rotational-degrees-of-freedom model of the human spine using optimization constrained to equilibrium and stability requirements is developed and used to simulate several symmetric tasks in upright and flexed standing postures. Predictions of this stability and kinematics-driven (S+KD) model for trunk muscle forces and spine compressive/shear loads are compared to those of our existing kinematics-driven (KD) model where both translational and rotational degrees-of-freedom are included but redundancy is resolved using equilibrium conditions alone. Unlike the KD model, the S+KD model predicted abdominal co-contractions that, in agreement with electromyography data, increased as lifting height increased at a constant horizontal moment arm. The S+KD model, however, could not fully explain the CNS strategy in activating antagonistic muscles for most of the remaining tasks. Despite quite distinct activities in individual muscles, both models predicted L4-L5 intradiscal pressure that matched the in vivo data, the L4-S1 compression loads, and the sum of all trunk muscle forces. For modeling applications in ergonomics, where the compressive spine loads are of interest, the two models yielded <15% difference. In the field of rehabilitation, where detailed muscle forces are required, the S+KD model explained more properly the CNS strategy in activating the antagonistic muscles for some tasks.


Assuntos
Vértebras Lombares , Fenômenos Mecânicos , Modelos Biológicos , Músculos , Vértebras Torácicas , Tronco , Fenômenos Biomecânicos , Vértebras Lombares/fisiologia , Músculos/fisiologia , Amplitude de Movimento Articular , Medição de Risco , Rotação , Vértebras Torácicas/fisiologia , Tronco/fisiologia
11.
Drug Res (Stuttg) ; 63(12): 614-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23828271

RESUMO

In this study, new glibenclamide analogues (5a-d) with substituted pharmacological triethoxysilyl propan, allyl and ethoxyphenyl groups for cyclohexyl moiety have been synthesized by condensing sulfonamide (4) with related isocyanate or isothiocyanate's compounds. The newly synthesized drugs were evaluated for their antihyperglycemic and antihyperlipidemic activities with streptozotocin (STZ)-induced diabetic rats. All showed hypoglycemic and hypolipidemic activities compared to the control animals but 5c and 5d exhibited more and significant lowering blood activities similar to glibenclamide. This was concerned with identical affinities to bind with SUR1 receptor. Moreover, the new drugs displayed high efficiency for reducing serum LDL level which resulted in a high HDL/LDL ratio as a good lipid profile compared to other groups.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Glibureto/farmacologia , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Animais , Glicemia/efeitos dos fármacos , HDL-Colesterol/sangue , LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Glibureto/análogos & derivados , Glibureto/síntese química , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Hipolipemiantes/síntese química , Hipolipemiantes/química , Masculino , Ratos , Estreptozocina , Relação Estrutura-Atividade , Receptores de Sulfonilureias/metabolismo
12.
Clin Exp Dermatol ; 34(8): e558-60, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19489870

RESUMO

We describe an 18-year-old girl with systemic lupus erythematosus (SLE) who had cutaneous papulonodular mucinosis (PNM) as the first sign of SLE. She presented with multiple flesh-coloured papules on the face, abdomen and limbs. Histological examination of a biopsy taken from a papule showed diffuse deposition of mucin throughout the dermis, and direct immunofluorescence of lesional skin showed a dermoepidermal junction band composed of IgG, IgM and C3, consistent with PNM. Investigations showed that that the patient had leucopenia, positive antinuclear and anti-double-stranded DNA antibodies and lupus nephritis. PMN can be an unusual clinical presentation of SLE.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Mucinoses/etiologia , Mucinas/metabolismo , Adolescente , Anticorpos/análise , DNA/imunologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/patologia , Mucinoses/patologia
13.
Indian J Dermatol ; 54(3): 247-50, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20161856

RESUMO

BACKGROUND: Skin lesions - benign and malignant - occur frequently in organ transplant recipients receiving long-term immunosuppressive therapy. These patients are at greater risk of skin cancers. AIMS: To study dermatologic problems in renal transplant recipients (RTRs). METHODS: One hundred patients (53 men and 47 women) were consecutively examined for benign and malignant skin complications since transplantation in Razi Hospital in Tehran Medical University. The main immunosuppressive therapy regimen in these patients was a combination of prednisolone, azathioprine, and cyclosporine. RESULTS: The early and most common complication was cosmetic side effects that occurred in 98% patients. Skin infections occurred in 83% of the patients and most of them were viral infections (65%), especially of human papilloma viruses (HPVs) in 40% of the patients. We found six cases of malignancy in these patients in that four cases were skin cancers, including one case of SCC, one BCC, and two cases of Kaposi's sarcoma. Dermatologic problems occur most frequently in RTRs, especially skin cancers which have higher frequency in these patients than general population, particularly, Kaposi sarcoma. Sun exposure has an important role in developing epithelial skin cancers following transplantation. The age of developing skin cancer in these patients was early than normal population. CONCLUSION: Our results emphasize the importance of dermatologic examinations and monitoring RTRs to obtain an early diagnosis and treatment of cutaneous manifestations.

14.
Clin Exp Dermatol ; 32(3): 256-60, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17355277

RESUMO

BACKGROUND: Recent reports have revealed the relatively high incidence of pemphigus in Iran. Occupational exposure and personal habits have been suggested to play a role in the aetiopathogenesis of this life-threatening disease. AIM: In order to analyse the association of environmental factors with pemphigus, we conducted a case-control study to evaluate the possible role of smoking, pesticide exposure and hormonal factors in Iran. METHODS: This study was conducted in Iran using a structured questionnaire. Questions included information on patients' smoking habits, occupational exposure to pesticides, use of oral contraception (OC) and number of pregnancies. RESULTS: We enrolled 210 patients with pemphigus and 205 control subjects. Fewer of patients with pemphigus (17.1%) reported a current or past history of smoking, which was statistically different from the control group (27.3% smokers). The duration of smoking and the number of cigarettes smoked daily was also significantly lower in patients. Although OC use was significantly higher in women with pemphigus, the mean number of pregnancies was not different between the two groups. Occupational exposure to pesticides was significantly higher in patients with pemphigus (14.8%) than in controls (5.4%); patients with pemphigus were exposed to pesticides three times more often than were healthy subjects. CONCLUSION: As a positive history of smoking was lower in patients with pemphigus compared with healthy subjects, it seems that smoking is a protective factor in pemphigus. This should encourage further investigations, searching for novel therapies. If pesticides and OC are confirmed as triggering factors, their cessation might reduce the need for pharmacological therapy.


Assuntos
Anticoncepcionais Orais Hormonais/efeitos adversos , Exposição Ocupacional/efeitos adversos , Pênfigo/induzido quimicamente , Praguicidas/toxicidade , Fumar/efeitos adversos , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Pênfigo/epidemiologia , Gravidez , Fatores de Risco , Inquéritos e Questionários
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