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1.
Sci Rep ; 10(1): 10545, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601374

RESUMO

We analyse possibilities to quantitatively evaluate the surface second-order optical nonlinearity in noncentrosymmetric materials based on polarization-resolved analysis of far-field radiation patterns of second-harmonic generation. We analytically demonstrate that for plane-wave illumination the contribution to the second-harmonic signal from the surface of a nonlinear medium exhibits different polarization properties and angular dependencies compared to the contribution from the bulk. In view of this, we optimize the illumination geometry in order to enable the most efficient separation and comparison of both nonlinearities. Furthermore, we consider the illumination of an AlGaAs slab by a tightly-focused linearly-polarized Gaussian beam as an alternative measurement geometry. It is found that the reliable separation of the surface nonlinearity contribution as well as a wide range of detectable values can be achieved with this geometry as well.

2.
Andrologia ; 49(2)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27147301

RESUMO

We designed this experiment to evaluate the effects of nortriptyline on testicular injury after torsion/detorsion (T/D). Ninety-six adult Wistar rats were divided into six groups 16 each in control group (Group 1), sham operated (Group 2), T/D + saline (Group 3), and in groups 4-6; were administered 2, 10 and 20 mg kg-1 , i.p. of nortriptyline 30 and 90 min after torsion respectively. Testicular torsion was created by twisting the right testis 720° in clockwise direction for 1 h. In six rats of each group, tissue MDA level and caspase-3 activity increased and the activities of catalase, superoxide dismutase and glutathione peroxidase decreased in compared with control group 4 h after detorsion (P < 0.001). In six rats of each group 24 h after detorsion, histopathological changes and germ cell apoptosis were significantly deteriorated by measuring mean of seminiferous tubules diameters (MSTD) and TUNEL test. Moreover, 30 days after T/D, sperm concentration and motility were examined in rest of rats. Pre- and post-reperfusion nortriptyline could reduce MDA and caspase-3 levels and normalise antioxidant enzymes activities, dose dependently. Germ cell apoptosis was significantly decreased, and the MSTD, as well as sperm functions, were significantly improved. Inhibition of mitochondrial permeability transition pore is probably involved in protective effects of nortriptyline against testicular T/D cell damages.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Apoptose/efeitos dos fármacos , Citoproteção , Nortriptilina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Torção do Cordão Espermático/complicações , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Inibidores da Captação Adrenérgica/administração & dosagem , Animais , Caspase 3/metabolismo , Catalase/metabolismo , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Malondialdeído/metabolismo , Nortriptilina/administração & dosagem , Ratos , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Contagem de Espermatozoides , Torção do Cordão Espermático/patologia , Espermatozoides/patologia , Superóxido Dismutase/metabolismo , Testículo/irrigação sanguínea , Testículo/patologia
3.
Toxicol Ind Health ; 32(6): 1135-42, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25342670

RESUMO

Cucumbers grown in two different greenhouses were exposed to mancozeb and carbaryl at different times. The effects of 10-day preharvest period, water and detergent washing, peeling, predetermined storage period at 4°C (refrigeration), and fermentation on the reduction of residue levels in the plant tissues were investigated. Mancozeb and carbaryl residues in cucumbers were determined by gas chromatography-electron capture detection. Results showed that residue levels in samples, which were collected after 10 days following the pesticide application, were significantly lower than the samples collected after 2 h subsequent to the pesticide application. The culinary applications were effective in reducing the residue levels of the pesticides in cucumbers. As a result, non-fermentative pickling in sodium chloride and acetic acid was the most effective way to reduce the mancozeb and carbaryl residues of the cucumbers.


Assuntos
Carbaril/análise , Cucumis sativus/química , Maneb/análise , Resíduos de Praguicidas/análise , Zineb/análise , Fermentação , Análise de Alimentos , Contaminação de Alimentos/análise , Armazenamento de Alimentos , Frutas/química
4.
Environ Monit Assess ; 185(12): 10333-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23842607

RESUMO

The present study is an attempt to evaluate the heavy metal contamination in the marine environment of the Caspian Sea of Iran. The concentrations of zinc, chromium, cadmium, and lead were measured in water and dorsal muscle of fish sampled from 10 selected stations along Gorgan coast using atomic absorption spectrophotometry during summer of 2011. The average concentrations of lead in water and fish samples (115.29 ± 14.78 and 113.23 ± 27.01 µg/L) were significantly higher than that of cadmium and chromium (P < 0.05). The highest heavy metals content was observed in Cyprinus carpio samples. The heavy metals concentrations in the samples were within the acceptable recommended standards. But, elevating levels of heavy metals in water and fish made a serious concern about ecosystem and food chain contamination. It is recommended that protective authorities should carry out a continual assessment on the levels of pollutants in the sea.


Assuntos
Monitoramento Ambiental , Peixes/metabolismo , Metais Pesados/análise , Alimentos Marinhos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Animais , Irã (Geográfico) , Metais Pesados/metabolismo , Alimentos Marinhos/estatística & dados numéricos , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/estatística & dados numéricos
5.
Bull Environ Contam Toxicol ; 89(2): 419-23, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22664555

RESUMO

In this study, concentrations of zinc, chromium, cadmium and lead were determined in water and three species of fish sampled from 10 selected stations along Gorgan coast using atomic absorption spectrophotometery, summer 2009. Mean lead levels in water and fish samples (119.50 ± 22.24 µg/L and 113.80 ± 33.11 µg/kg) were significantly higher than that of cadmium and chromium (p < 0.05). Cyprinus carpio had highest metals content than Mugila auratus and Rutilus frisikutum. The evaluated metals values in water collected from Gomishan wetland (Pb, Cd, Cr and Zn values are 145.31 ± 35.32, 120.46 ± 11.44, 96.47 ± 6.05 and 82.02 ± 34.37 µg/L, respectively) were higher than the other sampling sites. The result is consistent with the findings accessed by evaluation of the metals in fish specimens. The metals concentrations in the fish and water samples were below the recommended limits. But, elevating levels of metals in water and fish made a serious concern about ecosystem and food chain contamination.


Assuntos
Monitoramento Ambiental/métodos , Peixes , Sedimentos Geológicos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Animais , Cádmio/análise , Cromo/análise , Irã (Geográfico) , Chumbo/análise , Oceanos e Mares , Zinco/análise
6.
Case Rep Med ; 2012: 695627, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22536265

RESUMO

We report a 41 years old man with rapidly growing and tender lump on the anteromedial surface of tibia. The patient had the history of gastrectomy and gastrojejunostomy due to gastric carcinoma. On admission, the Simple X-ray of lower extremity disclosed a slight thinning of the anterior cortex of tibia without cortical destruction. The whole-body bone scan with (99m)TC MDP revealed activity of lesion in all 3 phases. The histopathological evaluation showed an infiltration of bone with tumor cells. Review No the literature revealed in previous cases of skeletal metastasis from gastric cancer in the tibia like this.

7.
Pharmacogn Mag ; 6(23): 176-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20931075

RESUMO

Plants are used worldwide for the treatment of diseases, and novel drugs continue to be developed through research from plants. There are more than 20,000 species of plants used in traditional medicines, and these are all potential reservoirs for new drugs. Cucurbitapepo has been used in traditional folk medicine to treat cold and alleviate ache. Previous pharmacological tests have shown that it possesses antiviral, anti-inflammatory, and analgesic effects. Also, Solanum nigrum has been used as a diuretic and an antipyretic agent and it has also been used to cure inflammation, edema, mastitis and hepatic cancer. In this investigation, cytotoxicity of specific concentrations of hydro-alcoholic extracts of C. pepo and S. nigrum was studied on normal [Chinese hamster ovarian cells (CHO) and rat fibroblast] and cancer (HepG2 and CT26) cell lines. The cytotoxic effects and IC(50) of the extracts on the selected cell lines were studied followed by colonogenic assay method. The results showed that IC(50) of S. nigrum extract was significantly lower than that of the C. pepo extract on all four cell lines (P < 0.05). On the other hand, IC(50) of S. nigrum extract was significantly higher than the extract of Taxus baccata and Cisplatin, herbal and chemical control positive anticancer compounds, respectively, on all four cell lines (P < 0.05). As a result, it is concluded that the extract of S. nigrum has almost similar cytotoxicity to the extract of T. baccata on cancer cells.

8.
Pharmacogn Mag ; 6(22): 102-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20668574

RESUMO

Isolation and identification of some potent anti-tumor compounds from medicinal plants has motivated researchers to screen different parts of plant species for the determination of anti-tumor effects. In this study, cytotoxic effects and IC(50) of specific concentrations of hydro-alcoholic extracts of fruits of Juniperus sabina and leaves of Zataria multiflora were compared with hydro-alcoholic extract of bark of Taxus baccata and Cisplatin, well-known anticancer compounds, on normal (CHO and rat fibroblast) and cancer (HepG2 and SKOV3) cell lines. The hydro-alcoholic extracts of the plants were prepared by percolation. The cytotoxic effects and IC(50) of the extracts on the cell lines were studied followed by colonogenic assay after 72 h incubation. The results showed that the extract of Juniperus sabina possesses lower IC(50) in comparison with Zataria multiflora extract on all 4 normal and cancer cell lines (P<0.05); but, IC(50) of the Juniperus sabina extract was significantly higher than the Taxus baccata extract and Cisplatin on all 4 normal and cancer cell lines (P<0.05). As a result, it is concluded that the extract of J. sabina has almost similar cytotoxicity with the extract of Taxus baccata on cancer cells.

9.
Pak J Biol Sci ; 12(14): 1041-4, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19947184

RESUMO

The importance of trace elements in chronic inflammatory diseases is related to their cofactor role in immune system functions and in different metabolic processes in articular tissues. The aim of this study was to compare serum levels of Cu, Zn and Zn/Cu ratio in Rheumatoid Arthritis (RA) patients with healthy volunteers in Sari Rheumatology clinic, 2007. Zn and Cu plasma concentrations were assayed using atomic absorption spectrophotometery in 40 selected RA patients sera based on sex and age compared with healthy volunteers. Statistical analysis was performed by SPSS 10 software using independent sample t-test. Zn plasma content in patient group was significantly lower (p = 0.02) than that in healthy group. Also, Cu plasma content showed no differences in comparison with healthy group (p = 0.15). Results showed no correlation between Cu and Zn plasma concentrations in patient group (p = 0.946). In contrast, significant positive correlation was found between Zn and Zn/Cu ratio (p = 0.000); but decreased Zn/Cu ratio was more influenced by diminished Zn concentration. The study showed that spreading of RA in Iranian Society is related to age, sex, career and nutrition of the patients. However, consumption of Zn and Cu supplements in RA patients may be suggested by future investigations.


Assuntos
Artrite Reumatoide/sangue , Cobre/sangue , Zinco/sangue , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oligoelementos/sangue , Adulto Jovem
10.
Toxicol Ind Health ; 25(8): 517-23, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19825858

RESUMO

In this study, the concentrations of lindane residues (organochlorine pesticides) were analyzed in samples of cultivated cucumbers (Cucumis sativus L.) and four species of most consumed fish (Sefid, Koli, Kilca and Kafal fish). Samples of cucumber were collected from five sites in Sari city (north, south, east, west and central areas) and samples of fish were caught using electric fishing from four major fishing centers (Chalous and Babolsar cities, Khazar Abad and Miankaleh regions) in Mazandaran province of Iran. Quantitative determination of the lindane content was performed by gas chromatography electron-capture detection (GC-ECD). The results showed that the concentration of lindane in cucumber samples and in the dorsal muscle of the selected fish were less than the Food and Agriculture Organization/World Health Organization (FAO/WHO) recommended intake.


Assuntos
Cucumis sativus , Produtos Pesqueiros/análise , Peixes/metabolismo , Hexaclorocicloexano/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análise , Análise de Variância , Animais , Monitoramento Ambiental , Contaminação de Alimentos , Hidrocarbonetos Clorados/análise , Irã (Geográfico) , Oceanos e Mares
11.
Biol Trace Elem Res ; 132(1-3): 144-52, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19415186

RESUMO

In this study, we investigate the toxic effects of cobalt chloride on some hematological factors of the carp Cyprinus carpio, such as white blood cell count, red blood cell count, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. At first, LC50 of cobalt in C. carpio was measured during 96 h after exposure. Also, physicochemical parameters of water including pH, dissolved oxygen, viscosity, temperature, and conductivity were monitored, continuously. The results showed that LC50 values of cobalt in C. carpio were 327 and 328 mg/L in two replicates, respectively. Then, the changes in some hematological factors in the five treatment groups placed under concentration of 100, 200, 300, 400, and 500 mg/L cobalt were compared with the control group. Based on hematological tests conducted in this research, exposure of carp to 500- and 300-mg/L concentrations of cobalt in 48 h showed significant difference (p<0.05) in white blood cell count. The concentration of 500 mg/L cobalt in 24 h showed a significant difference in the amount of hemoglobin, number of red blood cells, and hematocrit level as compared with the control group. The concentration of 100 mg/L cobalt in 48 h did not show a significant difference in comparison with the control group (p>0.05). Also, the concentration of 500 mg/L cobalt in 24 h showed a significant difference in the amount of mean corpuscular volume and mean corpuscular hemoglobin as compared with the control group and other treatments. Also, the percentage of mean corpuscular hemoglobin concentration in a concentration of 200 mg/L cobalt in 24 h showed a significant difference as compared with the control group and other treatments.


Assuntos
Cobalto/toxicidade , Animais , Carpas , Contagem de Eritrócitos , Hematócrito , Testes Hematológicos , Hemoglobinas/efeitos dos fármacos , Contagem de Leucócitos
12.
Biol Trace Elem Res ; 125(2): 97-108, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18716717

RESUMO

Changes in the cupper (Cu) and zinc (Zn) concentrations have been reported previously in idiopathic dilated cardiomyopathy (IDCMP). As a result of controversial results, the aim of this study was to compare the Zn and Cu concentrations and Zn/Cu ratio of IDCMP patients to healthy volunteers. In addition, the correlation of Cu and Zn levels with age has been evaluated. The study population consisted of 18 IDCMP patients and 27 healthy volunteers. IDCMP patients had normal angiography with echocardiography supporting cardiomyopathy without pericardial and valvular diseases. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week ago. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with SPSS 10 software with independent sample t test for comparing the level of Cu and Zn of IDCMP patients with normal subjects and Pearson correlation to determine the correlation between numeric data. P < 0.05 was considered as significant differences. There was a trend for a lower Zn level in IDCMP patients compared to healthy volunteers. (0.97 +/- 0.25 mg/l vs. 1.12 +/- 0.42 mg/l, respectively). The mean Cu levels of IDCMP and normal subjects were 1.33 +/- 0.20 mg/l and 1.31 +/- 0.23 mg/l, respectively. There was a significant difference in Zn/Cu ratio among patients based on the NYHA classification of heart failure (P = 0.003). Age was negatively correlated with Zn levels in IDCMP group (P = 0.037) and positively with Cu levels in healthy volunteers (P = 0.012). A lower Zn level in IDCMP patients compared to healthy volunteers and specially a significant difference in Zn/Cu ratio of patients based on their NYHA classification would suggest a critical role of zinc and Cu imbalance in development of IDCMP.


Assuntos
Cardiomiopatia Dilatada/sangue , Cobre/sangue , Saúde , Zinco/sangue , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Int J Pharm ; 246(1-2): 171-7, 2002 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-12270619

RESUMO

Eudragit RS and RL are biocompatible non-swelling polymers that widely used in the preparation of sustained release drug delivery systems. In this study, the effect of thermal treating on the tensile strength of tablets and release of indomethacin from Eudragit RS and RL matrices were investigated. The results showed that thermal treating at 40 degrees C has no effect on the release of the drug, whereas heat-treating at temperatures higher than 50 or 60 degrees C decreases the release rate of indomethacin from Eudragit RS or RL, respectively. It was shown that the duration of the heat treatment was also an important factor in controlling the release rate of indomethacin from Eudragit matrices. The results showed that an increase in the duration of the heat treatment from 2 to 24 h resulted in a reduction in the release rate of the drug. The heating of the matrices over 24 h had no significant effect on the release rate of indomethacin. It was shown that heat treatment of the matrices over the glass transition temperature of the polymer can prolong the drug release but had no significant effect on the tensile strength of tablets.


Assuntos
Resinas Acrílicas/química , Calefação/métodos , Indometacina/química , Polímeros/química , Preparações de Ação Retardada , Portadores de Fármacos , Composição de Medicamentos , Microscopia Eletrônica de Varredura , Porosidade , Solubilidade , Comprimidos , Resistência à Tração , Fatores de Tempo
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