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1.
Sci Rep ; 13(1): 16569, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789120

RESUMO

This investigation aims to assess the mechanical behavior and energy absorption properties of the open-cell nickel foams. The metal foams produced by electroforming of nickel on PU foams, also a heat treatment has applied to evaporate the PU foam, then a uniaxial compression test was applied to measure maximum compressive strength, energy absorption density, efficiency, and normalized stresses. The results indicate that compared with typical open-cell nickel foams and polymer precursors when the electroforming time is 12 h and a heat treatment has applied, the aforementioned properties of the metal foams had a significant improvement. Improvement of properties will change by increasing the time of electroforming. The heat treatment improved the energy absorption density of open-cell nickel foams for 3.7 times. For the best sample which is a metal foam with 12 h of electroforming with heat treatment the first maximum compressive strength, energy absorption density, and energy absorption efficiency reach 1.84 (MPa), 3.29 (mJ/mm3), and 73%, respectively.

2.
J Hosp Infect ; 139: 82-92, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37308061

RESUMO

BACKGROUND: Surgical site infection (SSI) is a health-threatening complication following caesarean section (CS); however, to the authors' knowledge, there is no worldwide estimate of the burden of post-CS SSIs. Therefore, this systematic review and meta-analysis aimed to estimate the global and regional incidence of post-CS SSIs and associated factors. METHODS: International scientific databases were searched systematically for observational studies published from January 2000 to March 2023, without language or geographical restrictions. The pooled global incidence rate was estimated using a random-effects meta-analysis (REM), and then stratified by World-Health-Organization-defined regions as well as by sociodemographic and study characteristics. Causative pathogens and associated risk factors of SSIs were also analysed using REM. Heterogeneity was assessed with I2. RESULTS: In total, 180 eligible studies (207 datasets) involving 2,188,242 participants from 58 countries were included in this review. The pooled global incidence of post-CS SSIs was 5.63% [95% confidence interval (CI) 5.18-6.11%]. The highest and lowest incidence rates for post-CS SSIs were estimated for the African (11.91%, 95% CI 9.67-14.34%) and North American (3.87%, 95% CI 3.02-4.83%) regions, respectively. The incidence was significantly higher in countries with lower income and human development index levels. The pooled incidence estimates have increased steadily over time, with the highest incidence rate during the coronavirus disease 2019 pandemic (2019-2023). Staphylococcus aureus and Escherichia coli were the most prevalent pathogens. Several risk factors were identified. CONCLUSION: An increasing and substantial burden from post-CS SSIs was identified, especially in low-income countries. Further research, greater awareness and the development of effective prevention and management strategies are warranted to reduce post-CS SSIs.


Assuntos
COVID-19 , Infecções Estafilocócicas , Humanos , Feminino , Gravidez , Infecção da Ferida Cirúrgica/prevenção & controle , Incidência , Cesárea/efeitos adversos , COVID-19/complicações , Infecções Estafilocócicas/epidemiologia
3.
BJOG ; 127(7): 800-809, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31967727

RESUMO

BACKGROUND: Results of studies that have assessed the accuracy of the endometriosis Fertility Index (EFI) for predicting non-assisted reproductive technology (ART) pregnancy are inconsistent. OBJECTIVE: We intended to evaluate the accuracy of EFI for the prediction of non-ART pregnancy. SEARCH STRATEGY: Embase, Medline, Scopus and Web of Science were searched up to 5 October 2019. SELECTION CRITERIA: We included studies that used EFI to predict non-ART pregnancy in women with surgically documented endometriosis. DATA COLLECTION AND ANALYSIS: A total of 5547 studies were identified, from which we included 17 studies on 4598 women in the meta-analysis. Eight studies were classified as good quality, and the rest were considered to be of fair quality. Only five (29.41%) studies used appropriate approaches to account for potential confounders. Pooled effect sizes with corresponding 95% CI were calculated using random-effects model. MAIN RESULTS: The cumulative non-ART pregnancy rate at 36 months was 10% (95% CI: 3, 16%; P < 0.001) for women with an EFI of 0-2, which significantly increased to 69% (95% CI: 58, 79%; P < 0.001) for women with an EFI of 9-10. Compared with women with an EFI of 3-4 (18%, 95% CI: 12, 24%; P < 0.001), the combined cumulative non-ART pregnancy rates were 44% (95% CI: 26, 63%; P < 0.001) for women with an EFT of 5-6 and 55% (95% CI: 47, 64%; P < 0.001) for women with an EFI of 7-8. Paired comparison by the chi-square test showed a significant difference between all categories (P < 0.001). The odds ratio (OR) for EFI was 1.33 (95% CI: 1.17, 1.49, P < 0.001) and the summary area under the curve (AUC) was 72% (95% CI: 65, 80%, P < 0.001). CONCLUSION: The current findings highlighted the good performance of the EFI score in predicting the non-ART pregnancy rate. However, these findings should be considered with caution because of the substantial heterogeneity between studies. TWEETABLE ABSTRACT: Review findings show the merits of Endometriosis Fertility Index as having a prognostic ability for non-assisted reproductive technology pregnancy.


Assuntos
Endometriose/complicações , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Infertilidade Feminina/etiologia , Complicações Pós-Operatórias/etiologia , Medição de Risco/métodos , Adulto , Área Sob a Curva , Endometriose/fisiopatologia , Endometriose/cirurgia , Feminino , Fertilidade , Humanos , Razão de Chances , Período Pós-Operatório , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Prognóstico
4.
Sci Rep ; 6: 38509, 2016 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-27917956

RESUMO

A stable capillary liquid jet formed by an electric field is an important physical phenomenon for formation of controllable small droplets, power generation and chemical reactions, printing and patterning, and chemical-biological investigations. In electrohydrodynamics, the well-known Taylor cone-jet has a stability margin within a certain range of the liquid flow rate (Q) and the applied voltage (V). Here, we introduce a simple mechanism to greatly extend the Taylor cone-jet stability margin and produce a very high throughput. For an ethanol cone-jet emitting from a simple nozzle, the stability margin is obtained within 1 kV for low flow rates, decaying with flow rate up to 2 ml/h. By installing a hemispherical cap above the nozzle, we demonstrate that the stability margin could increase to 5 kV for low flow rates, decaying to zero for a maximum flow rate of 65 ml/h. The governing borders of stability margins are discussed and obtained for three other liquids: methanol, 1-propanol and 1-butanol. For a gravity-directed nozzle, the produced cone-jet is more stable against perturbations and the axis of the spray remains in the same direction through the whole stability margin, unlike the cone-jet of conventional simple nozzles.

5.
Horm Metab Res ; 48(7): 446-51, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27050252

RESUMO

The current study was conducted to assess the effects of vitamin D-K-calcium co-supplementation on endocrine, inflammation, and oxidative stress biomarkers in vitamin D-deficient women with polycystic ovary syndrome (PCOS). This randomized double-blind, placebo-controlled trial was performed on 60 vitamin D-deficient women diagnosed with PCOS aged 18-40 years old. Participants were randomly allocated into 2 groups to intake either 200 IU vitamin D, 90 µg vitamin K plus, 500 mg calcium supplements (n=30), or placebo (n=30) twice a day for 8 weeks. Endocrine, inflammation, and oxidative stress biomarkers were quantified at the beginning and the end of the study. After 8 weeks of intervention, compared with the placebo, vitamin D-K-calcium co-supplementation resulted in a significant reduction in serum-free testosterone (- 2.1±1.6 vs.+0.1±1.0 pg/ml, p<0.001) and dehydroepiandrosterone sulfate (DHEAS) levels (- 0.8±1.0 vs.-0.1±0.5 µg/ml, p=0.006). In addition, a significant increase in plasma total antioxidant capacity (TAC) (+ 75.7±126.1 vs.-80.4±242.8 mmol/l, p=0.005) and a significant difference in plasma malondialdehyde (MDA) concentrations (+ 0.03±0.6 vs.+1.4±2.4 µmol/l, p=0.005) was observed following the supplementation with vitamin D-K-calcium compared with the placebo. A trend toward a greater decrease in luteinizing hormone was observed in vitamin D-K-calcium co-supplement group compared to placebo group (- 7.0 vs.-1.2 IU/l, p=0.09). We did not find any significant effect of vitamin D-K-calcium co-supplementation on prolactin, follicle-stimulating hormone, 17-OH progesterone, inflammatory markers, and glutathione levels. Overall, vitamin D-K-calcium co-supplementation for 8 weeks among vitamin D-deficient women with PCOS had beneficial effects on serum DHEAS, free testosterone, plasma TAC, and MDA levels.


Assuntos
Cálcio/uso terapêutico , Sistema Endócrino/metabolismo , Inflamação/tratamento farmacológico , Estresse Oxidativo , Síndrome do Ovário Policístico/tratamento farmacológico , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/uso terapêutico , Vitamina K/uso terapêutico , Adulto , Biomarcadores/sangue , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Inflamação/complicações , Estresse Oxidativo/efeitos dos fármacos , Placebos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/complicações , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações
6.
Horm Metab Res ; 48(3): 185-90, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26267328

RESUMO

Selenium supplementation could be effective on reproductive outcomes, biomarkers of inflammation, and oxidative stress among women with polycystic ovary syndrome (PCOS). The aim of the study was to determine the effects of selenium supplementation on reproductive outcomes, biomarkers of inflammation, and oxidative stress in PCOS patients. The present randomized double-blind, placebo-controlled trial was conducted on 64 women aged 18-40 years old with PCOS at the clinic affiliated to Ardabil University of Medical Sciences, Ardabil, Iran. The participants were randomly assigned to 2 groups receiving either 200 µg selenium daily (n=32) or placebo (n=32) for 8 weeks. Hormonal profiles, biomarkers of inflammation, and oxidative stress were measured and compared both before and after the treatment. After 8 weeks of intervention, pregnancy rate in the selenium group was higher than in the placebo group: 18.8 (6/32) vs. 3.1% (1/32), p=0.04. In addition, alopecia (40.6 vs. 9.4%, p=0.004) and acne (46.9 vs. 12.5 %, p=0.003) decreased following the consumption of selenium supplements compared with placebo. Additionally, patients who received selenium supplements had significantly decreased serum dehydroepiandrosterone (DHEA) levels (p=0.02), hirsutism (modified Ferriman-Gallwey scores) (p<0.001), serum high sensitivity C-reactive protein (hs-CRP) (p=0.02), and plasma malondialdehyde (MDA) levels (p=0.01) compared with placebo. We did not observe any significant effects of taking selenium supplements on other hormonal profiles, nitric oxide (NO), and other biomarkers of oxidative stress. Taken together, selenium supplementation for 8 weeks among PCOS women had beneficial effects on reproductive outcomes, DHEA, hs-CRP, and MDA levels. Supporting Information for this article is available online at http://www.thieme-connect.de/products.


Assuntos
Biomarcadores/metabolismo , Suplementos Nutricionais , Inflamação/patologia , Estresse Oxidativo/efeitos dos fármacos , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/patologia , Reprodução/efeitos dos fármacos , Selênio/uso terapêutico , Adulto , Dieta , Feminino , Humanos , Pacientes Desistentes do Tratamento , Selênio/farmacologia , Resultado do Tratamento
7.
Int J Med Robot ; 11(4): 476-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25582358

RESUMO

BACKGROUND: Restorative dentistry simulation is one of the most challenging applications involving virtual reality and haptics. This paper presents a haptics-based tooth drilling simulator for dental education. METHODS: Unlike the existing methods, the force model is based on physical properties which consider the geometrical model of the tool. In order to provide uniform force feedback from tooth layers, a new approach is suggested in which the physical properties of each tooth voxel are subsequently used in calculating the feedback force. We implement a hashing algorithm for collision detection due to its reduced time complexity. The haptics algorithm has been implemented on a graphics processing unit using the CUDA toolbox. RESULTS: In parallel processing, the speed of haptic loop execution is increased almost 8 times. CONCLUSION: The proposed idea for force calculation leads to a uniform sensation of force. An important feature of the designed system is the capability to run in a real-time fashion.


Assuntos
Gráficos por Computador/instrumentação , Preparo da Cavidade Dentária/instrumentação , Procedimentos Cirúrgicos Robóticos/educação , Cirurgia Assistida por Computador/instrumentação , Dente/cirurgia , Tato , Simulação por Computador , Instrução por Computador/instrumentação , Instrução por Computador/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Modelos Biológicos , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Estresse Mecânico , Cirurgia Assistida por Computador/métodos , Dente/anatomia & histologia , Interface Usuário-Computador
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 130: 129-35, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24769384

RESUMO

Metal-semiconductor compounds, such as Ag/AgX (X=Cl, Br, I), enable visible light absorption and separation of photogenerated electron-hole through surface plasmon resonance (SPR) effect. However, the electron-hole generated and separated by light are vulnerable in Ag/AgX phase because of the occurrence of secondary recombined. In order to more effectively utilize the SPR photocatalytic effect, nanoparticles are located in a matrix. In this article, Ag/AgCl nanoparticles were synthesized in montmorillonite (MMT) matrix using dispersion method and light irradiation. The structure, composition and optical properties of such material were investigated by transmission electron microscopy (TEM), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), X-ray diffraction (XRD) and FTIR. Powder X-ray diffraction showed intercalation of Ag/AgCl nanoparticles into the clay layers. The as-prepared plasmonic photocatalyst exhibited an enhanced and stable photoactivity for the degradation of methylene blue (MB) under visible light. The high activity was attributed to the surface plasmon resonance (SPR) exhibited by Ag nanoparticles on the surface of AgCl. The detection of reactive species by radical scavengers displays that O2- and OH- are the main reactive species for the degradation of MB under visible light irradiation. The studies showed that 20 min illumination under visible light can complete degradation of methylene blue (MB), and indicate a high stability of photocatalytic degradation. The mechanism of separation of the photo-generated electrons and holes at the Ag/AgCl-MMT nanocomposite was discussed.


Assuntos
Bentonita/química , Azul de Metileno/química , Nanocompostos/química , Compostos de Prata/química , Prata/química , Catálise , Elétrons , Concentração de Íons de Hidrogênio , Luz , Microscopia Eletrônica de Transmissão , Compostos Orgânicos/química , Fotoquímica , Fotólise , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Ressonância de Plasmônio de Superfície , Difração de Raios X
9.
Eur J Pain ; 18(6): 853-61, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24347556

RESUMO

BACKGROUND AND METHOD: The aim was to investigate influence from variations in intensity of a painful conditioning stimulation (CS) on early (0-6 min) and prolonged (6-12 min) conditioned pain modulation (CPM) in volunteers during concurrent exposure to test stimuli (TS). CS was applied to either forearm using painful heat with an intensity of 2/10 and 5/10, respectively, rated on a 0-10 numerical pain rating scale. At a second session, CS with an intensity of 7/10 was applied to the arm using a tourniquet. Threshold and suprathreshold painful heat and pressure as well as painful repeated monofilament pricking (RMP) were assessed as TS. RESULTS: Regardless of TS, there was no significant difference in the magnitude of CPM within the same stimulus modality during the various intensities and phases of the CS. Significant modulation of heat pain thresholds (HPTs) was found during the early phase at 5/10 and 7/10, but not at 2/10. Only at 5/10 the prolonged CS resulted in a significant additional increase in HPT. During the early CS phase, CPM of suprathreshold heat pain was found at 2/10 and 5/10. The prolonged CS resulted in a significant additional temperature increase at 5/10. Only during the early phase significant CPM of pressure pain thresholds were found for all three pain intensities in conjunction with a significant CPM of suprathreshold pressure pain at 5/10. There was no CPM of RMP. CONCLUSION: The CS intensity and the duration of CPM modulated pain sensitivity differentially across TS modalities.


Assuntos
Condicionamento Psicológico/fisiologia , Nociceptividade/fisiologia , Limiar da Dor/fisiologia , Dor/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Fatores de Tempo , Adulto Jovem
10.
Res Pharm Sci ; 8(2): 91-5, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24019818

RESUMO

In this study the anticonvulsant effect of two dihydropyridine derivatives [diethyl -1,4- dihydro -2,6-dimethyl -4-(4- fluoro benzyl-2- methylthio -5- imidazolyl)-3,5- pyridine dicarboxilat (A) and diethyl -1,4-dihydro -2,6- diethyl -4-(4- fluoro benzyl-2- methylthio -5- imidazolyl)-3,5- pyridine dicarboxilat (B)] by pentylenetetrazole (PTZ) and electroshock in mice was evaluated. The latency and HLTE (hind limb tonic extensions), the duration of HLTE and the mortality protection in pentylenetetrazole test and the HLTE duration in electroshock test were assessed. Both compounds had significant differences with negative control in all doses used. There was no significant difference between nifedipine and B (96.7 and 169.2 mg/kg doses) in the starting point of HLTE and between nifedipine andA(62.2 and 108.9 mg/kg doses) in the duration of HLTE in the PTZ test. Also, there was no significant difference between nifedipine and B (96.7 and 169.2 mg/kg doses) andA(62.2 and 108.9 mg/kg doses) in electroshock test. All doses ofAand B and nifedipine showed less effect than phenytoin and valproate. This study showed that bothAand B have anticonvulsant activity in the PTZ-induced seizure model and the MES test. These compounds, thus, might be useful in the petit mal and grand mal epilepsy.

11.
J Dent (Tehran) ; 9(1): 14-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22924097

RESUMO

OBJECTIVE: Iron deficiency is the most common form of malnutrition in developing countries. Iron containing supplements have been used effectively to solve this problem. In children, because of teeth staining after taking iron drops, parents have the idea that iron drops are the cause of tooth decay; therefore, they limit this vital supplement in their children's diet. Hereby, we evaluate the histologic effect of iron containing supplements on tooth caries in rice rats with cariogenic or non-cariogenic diet. MATERIALS AND METHODS: Twelve rats were selected and divided into four groups for this interventional experimental study. Four different types of dietary regimens were used for four months; group A, cariogenic diet with iron containing supplements; group B, cariogenic diet without iron containing supplements; group C, non-cariogenic diet with iron containing supplements; group D, non-cariogenic diet without iron containing supplements. After sacrificing the rats, 20-micron histological sections of their posterior teeth were prepared using the Ground Section method, then they were studied under polarized light microscopy. In order to compare the progression of caries in different samples, the depth of the lesions in the enamel was measured as three grades I, II and III. RESULTS: The mean grade value of A, B, C and D groups were 1.61, 2.61, 1.37 and 1.80, respectively. Statistical analysis revealed that significantly fewer caries were seen in the group which had received iron containing supplements and cariogenic diet compared with cariogenic diet without iron supplements (p<0.05). CONCLUSION: Ferrous sulfate reduces the progression of dental caries in the cariogenic dietary regimen.

12.
Acta Physiol Hung ; 99(1): 87-93, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22425811

RESUMO

Several reports indicated the beneficial effects of short-term L-Arginine (L-Arg) administration on atherosclerosis processes. The aim of this study was to evaluate the effect of chronic L-Arg supplementation on serum lipid profile, aortic Fatty Streak (FS) formation, and serum Nitric oxide (NO) concentration in Normal Diet (ND) and High-Cholesterol Diet (HCD) fed rabbits. 24 male rabbits were randomly divided into four groups (n=6 in each group) (i): ND for seven months; (ii): ND for 1 month plus ND + L-Arg for six months; (iii): HCD (1%) for 1 month plus HCD (0.5%) for six months; (iv): HCD (1%) for 1 month plus HCD (0.5%) + L-Arg for six months. At the end of the study, histological evaluation of aortic FS formation was performed. Blood samples were taken for serum lipid profile and NO concentrations. L-Arg did not change serum total cholesterol, triglyceride, LDL and LDL/HDL ratio in normal and hypercholesterolemic rabbits (p>0.05). Histological examination of thoracic aortae revealed that the HCD group had higher FS formation compared to the ND group (2.1 ± 0.16 vs. 0 ± 0; respectively; p<0.05) and L-Arg supplementation did not attenuate FS formation in the HCD group (1.93 ± 0.17 compare to 2.1 ± 0.16; p>0.05). Serum NO level in the HCD group was higher than ND groups (p<0.05). Chronic L-Arg supplementation did not alter serum NO concentration either in the hypercholesterolemic or in the ND group (p>0.05). It seems that chronic L-Arg supplementation does not have beneficial effects on aortic fatty streak formation, serum lipids and NO concentrations in this model of experimental hypercholesterolemia.


Assuntos
Doenças da Aorta/tratamento farmacológico , Arginina/farmacologia , Hipercolesterolemia/tratamento farmacológico , Óxido Nítrico/sangue , Placa Aterosclerótica/tratamento farmacológico , Animais , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Colesterol na Dieta/farmacologia , Modelos Animais de Doenças , Hipercolesterolemia/metabolismo , Hipercolesterolemia/patologia , Lipídeos/sangue , Masculino , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Coelhos
13.
Trop Biomed ; 28(2): 411-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22041763

RESUMO

The present study aimed to establish a simple method to yield large amounts of Leishmania tropica amastigote-like forms in axenic cultures and to compare the superoxide dismutase (SOD) and glutathione peroxidase (GPX) enzymes at different stages of L. tropica. Different culture conditions were tested to find the optimum condition of axenic amastigotes generation. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were determined at logarithmic and stationary phases and axenic amastigote stage of the parasite. A high proportion (88%) of amastigote-like forms of L. tropica was observed in BHI medium supplemented with 20% FCS, pH 4.5, and incubated at 37ºC with 5% CO(2). The results showed that SOD activity was at the lowest level in the logarithmic phase of promastigotes and increased towards the stationary phase of promastigotes and amastigote stage. The results showed that the optimum condition for differentiation of L. tropica promastigotes to axenic amastigotes was BHI medium containing 20% FCS at pH 4.5, incubated at 37ºC in the presence of 5% CO(2). It seems that SOD, but not GPX is a major determinant of intracellular survival of the parasite.


Assuntos
Glutationa Peroxidase/metabolismo , Leishmania tropica/enzimologia , Leishmania tropica/crescimento & desenvolvimento , Parasitologia/métodos , Superóxido Dismutase/metabolismo , Meios de Cultura/química , Leishmania tropica/genética
14.
Persoonia ; 26: 57-69, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22025804

RESUMO

The Mycosphaerella complex is both poly- and paraphyletic, containing several different families and genera. The genus Mycosphaerella is restricted to species with Ramularia anamorphs, while Septoria is restricted to taxa that cluster with the type species of Septoria, S. cytisi, being closely related to Cercospora in the Mycosphaerellaceae. Species that occur on graminicolous hosts represent an as yet undescribed genus, for which the name Zymoseptoria is proposed. Based on the 28S nrDNA phylogeny derived in this study, Zymoseptoria is shown to cluster apart from Septoria. Morphologically species of Zymoseptoria can also be distinguished by their yeast-like growth in culture, and the formation of different conidial types that are absent in Septoria s.str. Other than the well-known pathogens such as Z. tritici, the causal agent of septoria tritici blotch on wheat, and Z. passerinii, the causal agent of septoria speckled leaf blotch of barley, both for which epitypes are designated, two leaf blotch pathogens are also described on graminicolous hosts from Iran. Zymoseptoria brevis sp. nov. is described from Phalaris minor, and Z. halophila comb. nov. from leaves of Hordeum glaucum. Further collections are now required to elucidate the relative importance, host range and distribution of these species.

15.
J Biomed Nanotechnol ; 7(3): 441-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21830486

RESUMO

Designing and preparation of magnesium alloys with adjustable biocorrosion rates in the human body and precipitation ability of bone-like apatite layer have been of interest recently. Application of metal matrix composites (MMC) based on magnesium alloys might be an approach to this challenge. The aim of this work was fabrication and evaluation of biocorrosion and bioactivity of a novel MMC made of magnesium alloy AZ91 as matrix and fluorapatite (FA) nano particles as reinforcement. Biodegradable Magnesium-nano fluorapatite metal matrix nanocomposite (AZ91-20FA) was made via a blending-pressing-sintering method. In vitro corrosion tests were performed for evaluation of biocorrosion behavior of produced AZ91-20FA nanocomposite. The results showed that the addition of FA nano particles to magnesium alloy can reduce not only the corrosion rate in a simulated body environment but also accelerate the formation of an apatite layer.


Assuntos
Apatitas/química , Magnésio/química , Nanocompostos/química , Nanopartículas/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
16.
Daru ; 19(4): 295-300, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22615672

RESUMO

BACKGROUND AND THE PURPOSE OF THE STUDY: It has been shown that Nigella sativa L. and Portulaca oleracea L. have many antioxidant components. In the present study, the cytoprotective effect of ethanolic and aqueous extracts of N.sativa and P.oleracea against hemolytic damages induced by free radical initiator, AAPH [2, 2' azobis (2- amidinopropane) hydrochloride] was evaluated. METHODS: Hemolysis was induced by addition of AAPH. To study the cytoprotective effect, aqueous (50, 200, 300, 400, 800 µg/ml) and ethanolic (25, 100, 150, 200 and 400 µg/ml) extracts of N. sativa and aqueous (25, 50, 100, 150, 200 and 400 µg/ml) and ethanolic (300, 600, 900, 1200 and 1800 µg/ml) extracts of P. oleracea were employed. RBCs were incubated with both extracts and AAPH at 37 °C for 6 hrs. In order to evaluate the impact of the time of addition, extracts were added one and 2 hrs after AAPH. Samples of suspensions were removed at different times and the degree of hemolysis was assessed spectrophotometrically by reading the absorption of supernatants at 540 nm. RESULTS: Aqueous (300, 400 and 800 µg/ml) and ethanolic (150, 200 and 400 µg/ml) extracts of N.sativa and also, aqueous (100, 150, 200 and 400 µg/ml) and ethanolic (1200, 1800 µg/ml) extracts of P.oleracea showed concentration-dependent cytoprotective effects. Addition of extracts one hour after AAPH reduced but did not eliminate protective activities of extracts. CONCLUSION: Cytorotective effect of aqueous and ethanolic extracts of N. sativa and P. oleracea against AAPH- induced hemolysis may be related to antioxidant properties of these plants.

17.
Tropical Biomedicine ; : 411-417, 2011.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-630077

RESUMO

The present study aimed to establish a simple method to yield large amounts of Leishmania tropica amastigote-like forms in axenic cultures and to compare the superoxide dismutase (SOD) and glutathione peroxidase (GPX) enzymes at different stages of L. tropica. Different culture conditions were tested to find the optimum condition of axenic amastigotes generation. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were determined at logarithmic and stationary phases and axenic amastigote stage of the parasite. A high proportion (88%) of amastigote-like forms of L. tropica was observed in BHI medium supplemented with 20% FCS, pH 4.5, and incubated at 37ºC with 5% CO2. The results showed that SOD activity was at the lowest level in the logarithmic phase of promastigotes and increased towards the stationary phase of promastigotes and amastigote stage. The results showed that the optimum condition for differentiation of L. tropica promastigotes to axenic amastigotes was BHI medium containing 20% FCS at pH 4.5, incubated at 37ºC in the presence of 5% CO2. It seems that SOD, but not GPX is a major determinant of intracellular survival of the parasite.

18.
Orbit ; 29(5): 286-90, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20712513

RESUMO

PURPOSE: To examine the microbiology and antibiogram of specimens from patients with dacryocystitis. METHODS: A total of 66 samples from lacrimal sac contents of 61 consecutive patients with acute and chronic dacryocystitis were obtained. These specimens were cultured for bacteria with a routine microbiological technique. Antibiograms were acquired from positive cultures. RESULTS: A total of 61 patients (12 patients with acute and 49 patients with chronic dacryocystitis) were included in this investigation with the average age of 40 (12-85) years (female = 74% and male = 26%). Five patients were culture-negative and five patients had mixed gram-positive cultures (a total of 66 samples were obtained). The total prevalence of gram-positive, gram-negative, and culture-negative samples were 71.2%, 21.2%, and 7.6%, respectively. The prevalence of gram-positive, gram-negative, and culture-negative samples were 77.4%, 18.9%, and 3.8% in the chronic and 46.2%, 30.8%, and 23.1% in the acute groups, respectively. The most prevalent pathogen in both groups was Staphylococcus epidermis. In 38% of patients the culture results were similar to those of the contralateral conjunctival flora. Gram-negative bacteria had a high sensitivity to ciprofloxacin and cephalexin while the gram-positive ones were highly sensitive to ceftriaxone and ampicillin. CONCLUSION: The responsible pathogens in acute and chronic dacryocystitis are significantly different. Because of the high prevalence of gram-negative bacteria and also culture-negative samples and considering the necessity of treatment in acute dacryocystitis, selecting an appropriate antibiotic with a good coverage of gram-negative and gram-positive bacteria seems essential.


Assuntos
Bactérias/isolamento & purificação , Dacriocistite/microbiologia , Infecções Oculares Bacterianas/microbiologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Técnicas Bacteriológicas , Criança , Doença Crônica , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
19.
Rev Sci Instrum ; 81(5): 053504, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20515136

RESUMO

The modified Rogowski sine-coil (MRSC) has been designed and implemented for the plasma column horizontal displacement measurements on small IR-T1 tokamak. MRSC operation has been examined on test assembly and tokamak. Obtained results show high sensitivity to the plasma column horizontal displacement and negligible sensitivity to the vertical displacement; linearity in wide, +/-0.1 m, range of the displacements; and excellent, 1.5%, agreement with the results of numerical solution of Biot-Savart and magnetic flux equations.

20.
Plant Dis ; 94(3): 375, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30754225

RESUMO

Phalaris paradoxa (hood canarygrass) is one of the most abundant weeds in wheat fields of Iran. In a survey conducted from 2005 to 2007 in Ilam (Dehloran City) and Golestan (Gorgan City) provinces, leaf blotch symptoms were prevalent on P. paradoxa. Initial symptoms were pale brown and necrotic lesions that were 3 to 4 mm long on the leaves. Severity of the disease on the lower leaves was higher than on the upper leaves. Pycnidia were observed on the adaxial surface of infected leaves, scattered or sometimes in clusters, dark brown, globose, and 70 to 90 µm in diameter, with the ostiole approximately 10 µm in diameter. Conidia were filiform, hyaline, 0 to 3 septate (mostly 1 septate), and 17 to 40 × 1.5 to 2.0 µm. Conidiogenesis type was holoblastic. On the basis of the above morphological characters, this species was identified as Septoria phalaridis Cocc. & Morini (2,3). Sequencing the internal transcribed spacer (ITS) region of the fungus (GenBank Accession No. GU123926) showed 98% homology to Mycosphaerella graminicola strain 687 and 97% to S. passerinii strain ATCC26515 (GenBank Accession Nos. AB435068.1 and AF181696.1). To confirm pathogenicity of the fungus, 25 P. paradoxa seedlings were inoculated at the three-leaf stage with 20 ml of 1 × 107 spores/ml suspension with a hand sprayer. Plants were covered with a clear polyethylene bag to increase humidity and prevent cross contamination. After 72 h, bags were removed and plants were kept in a greenhouse at 21 ± 2/16 ± 2°C (day/night) and a 16-h photoperiod. Control plants received sterilized distilled water only. Leaves of each plant were visually inspected every day and the appearance of disease symptoms was recorded. After 1 month, all inoculated leaves showed symptoms and signs of the disease such as chlorosis, necrosis, and pycnidia, whereas control plants showed no symptoms or signs of disease. The infected plant tissues were examined with a microscope, the pycnidia and pycnidiospores were measured, and S. phalaridis was reisolated from leaf lesions. The first description of S. phalaridis was on P. brachystachys (1); however, to our knowledge, this is the first report of this pathogen on P. paradoxa. In addition, this is a new fungal species for the mycobiota of Iran. Two voucher specimens (IRAN 14078 F and IRAN 14218 F) were deposited in the Fungus Collection of the Ministry of Jihad-e Agriculture, Tehran, Iran. References: (1) G. Cocconi and F. Morini. Mem. R. Accad. Sci. Ist. Bologna, Cl. Sci. Fis. Ser. 4, 6:371, 1884. (2) M. J. Priest. Fungi of Australia, Septoria. ABRS, Canberra. CSIRO Publishing, Melbourne, 2006. (3) D. N. Teterevnikova-Babayan. Fungi of the Genus Septoria in the USSR. Akademiya Nauk Armyanskoi SSR, Yerevan, 1987.

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