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31.
The present study aims to investigate the adverse effects of plant growth regulators : gibberellic acid (GA3) and indoleacetic acid (IAA) on testicular functions in rats, and extends to investigate the possible protective role of grape seed extract, proanthocyanidin (PAC). Male rats were divided into six groups; control group, PAC, GA3, IAA, GA3 + PAC and IAA + PAC groups. The data showed that GA3 and IAA caused significant increase in total lipids, total cholesterol, triglycerides, phospholipids and low-density-lipoprotein cholesterol in the serum, concomitant with a significant decrease in high-density-lipoprotein cholesterol, total protein, and testosterone levels. In addition, there was significant decrease in the activity of alkaline phosphatase, acid phosphatase, and gamma-glutamyl transferase. A significant decrease was detected also in epididymyal fructose along with a significant reduction in sperm count. Testicular lipid peroxidation product and hydrogen peroxide (H2O2) levels were significantly increased. Meanwhile, the total antioxidant capacity, glutathione, sulphahydryl group content, as well as superoxide dismutase, catalase, and glucose-6-phosphate dehydrogenase activity were significantly decreased. Moreover, there were a number of histopathological testicular changes including Leydig’s cell degeneration, reduction in seminiferous tubule and necrotic symptoms and sperm degeneration in both GA3- and IAA-treated rats. However, an obvious recovery of all the above biochemical and histological testicular disorders was detected when PAC seed extract was supplemented to rats administered with GA3 or IAA indicating its protective effect. Therefore it was concluded that supplementation with PAC had ameliorative effects on those adverse effects of the mentioned plant growth regulators through its natural antioxidant properties.  相似文献   
32.
The alleviative effects of two antioxidants, carnosine (Car) and melatonin (Mel), against titanium dioxide nanoparticles (TiO2‐NPs) toxicity‐induced oxidative and inflammatory renal damage were examined in rats. Administration of these antioxidants along with TiO2‐NPs effectively reduced serum urea, uric acid, creatinine, glucose, tumor necrosis factor‐α, interleukin‐6, C‐reactive protein, immunoglobulin G, vascular endothelial growth factor, and nitric oxide, as well as a significant amelioration of the decrease in glutathione levels in renal tissue was observed, compared to those in rats treated with TiO2‐NPs alone. The renoprotective properties of the antioxidants were confirmed by reduced intensity of renal damage as demonstrated by histological findings. In conclusion, Car and Mel play protective roles against TiO2‐NPs‐induced renal inflammation and oxidative injury, likely due to their antioxidant and anti‐inflammatory properties.  相似文献   
33.
Zinc oxide (ZnO) and ZnO:Cu nanoparticles (NPs) were synthesized using a rapid, controllable, one‐pot and room‐temperature pulsed UV‐laser assisted method. UV‐laser irradiation was used as an effective energy source in order to gain better control over the NPs size and morphology in aqueous media. Parameters effective in laser assisted synthesis of NPs such as irradiation time and laser shot repetition rate were optimized. Photoluminescence (PL) spectra of ZnO NPs showed a broad emission with two trap state peaks located at 442 and 485 nm related to electronic transition from zinc interstitial level (IZn) to zinc vacancy level (VZn) and electronic transition from conduction band to the oxygen vacancy level (VO), respectively. For ZnO:Cu NPs, trap state emissions disappeared completely and a copper (Cu)‐related emission appeared. PL intensity of Cu‐related emission increased with the increase in concentration of Cu2+, so that for molar ratio of Cu:Zn 2%, optimal value of PL intensity was obtained. The photocatalytic activity of Cu‐doped ZnO revealed 50 and 100% increasement than that of undoped NPs under UV and visible irradiation, respectively. The enhanced photocatalytic activity could be attributed to smaller crystal size, as well as creation of impurity acceptor levels (T2) inside the ZnO energy band gap.  相似文献   
34.

Purpose

To obtain protein hydrolysates from fresh water green algae Scenedesmus obliquus by three different enzymes and evaluate its antioxidant and antiviral activity.

Methods

Enzymatic hydrolysates of green algae Scenedesmus obliquus protein were prepared by treatment with: 1.2% solution of pepsin, trypsin or papain. Protein was extracted from S. obliquus by three different extraction methods. Protein extracts and hydrolysates were assessed from stained gels following SDS–PAGE of samples. Antioxidant activity of protein hydrolysates was investigated.

Results

S. obliquus cells and protein extracts were rich in Arg, Lys, Asp, Ala, and His. Protein hydrolyzed by papain (Sd1pa) and protein hydrolyzed by trypsin (Sd2Try) induced highest antioxidant activity based on 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging (41.41% and 40.62%) respectively, and on 2,2′-azinobis 3-ethyl-benzothiazoline-6-sulphonate (ABTS) radical (87.03% and 45.12%) respectively, at 150?µg/ml. The inhibitory effect and mode of action of protein hydrolysates were evaluated against Coxsackie B3 virus (CVB3). Protein hydrolyzed by papain (Sd2pa) and protein hydrolyzed by pepsin (Sd1pep) at 100?µg/ml exhibited antiviral activity (66.2% and 57.6%, respectively), against (CVB3) from all protein hydrolysates.

Conclusion

S. obliquus protein hydrolysates have a potential as antioxidative neutraceutical ingredients and a potential therapeutic agent against CVB3.  相似文献   
35.
36.
Nepeta is a perennial herbal plant that belongs to the Lamiaceae mint family. Nepta has different species that are widely used in the agriculture, medicine, and pharmaceutical industries. A field experiment was conducted in 2015 and 2016 to determine the effects of potassium humate foliar application [0 (control) and 400 ppm] on growth, essential oil and constituents of three Nepta species [Nepeta cataria (catnip), Nepeta cataria var. citriodora (lemon catnip), and Nepeta grandiflora (giant catmint)] under Egyptian conditions. In all three species, the application of potassium humate increased growth indicators, essential oil content (%) and yield (mL/plant), and flavonoids in each of the two harvests. However, the height of giant catmint was significantly higher than that of lemon catnip, which was higher than that of catnip. Lemon catnip that received potassium humate and harvested second gave the highest essential oil content and yield. The major constituents were geraniol and nepetalactone in catnip; citronellol and geraniol in lemon catnip; and o-cymene, c-terpinene, p-cymene and carvacrol in giant catmint. The highest p-cymene in giant catmint, citronellol in lemon catnip, and geraniol in catnip were obtained from the application of potassium humate, while the highest o-cymene, c-terpinene and carvacrol in giant catmint, geraniol in lemon catnip, and nepetalactone in catnip were obtained from control plants. This study demonstrated the variations among species of nepeta, and how they respond to the application of potassium humate. The findings of this study can guide the customization of potassium humate applications to the three species for achieving desired growth and essential oil production outcomes.  相似文献   
37.
Aim of work: To estimate the frequency of mutations involving exons 6, 8 and 9 of Adenosine triphosphate-binding cassette, subfamily B, member 4 (ABCB4) gene among children with progressive intrahepatic cholestasis with high γ-GT activity (PFIC3).

Subjects and methods: Cross sectional study was conducted on 30 children with PFIC3. Genotyping was performed by sequencing analysis of exons 6, 8 and exon 9 of ABCB4 gene.

Results: Heterozygous synonymous polymorphic variant was detected in exon 6 (rs 1202283) and in exon 8 (rs 2109505). No mutations in studied exons were detected.

Conclusion: Exons 6, 8 and 9 mutations of ABCB4 gene are not common among Egyptian children with PFIC3.  相似文献   
38.
Breast cancer (BC) is the most common neoplasm among women in most developed countries, including Egypt. Elevated levels of certain proteins in human BC are associated with unfavorable prognosis and progressive stages of the disease. The aim of our study was to evaluate the protein expression profile and prognostic significance of cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2), MMP-9 and membrane type 1-MMP (MT1-MMP) and their interaction in operable BC patients. The protein expression of COX-2, MMP-2 and MT1-MMP were evaluated by western blot technique, whereas enzymatic activity of MMP-2 and MMP-9 was determined by zymography in 47 breast cancer patients as well as normal adjacent tissues. Also, the correlation between these proteins and age, tumor size, LN stage, TNM stage, estrogen receptor, progesterone receptor, disease-free survival, and overall survival (OS) has been investigated. As compared to adjacent normal tissues, COX-2, MMP-2 and MT1-MMP were over-expressed in 43, 64, and 60 % of tumor tissues, respectively. In the same pattern, the activity of MMP-2 (62 %) and MMP-9 (45 %) was elevated in BC tissues. Multivariate analysis showed a positive correlation between the protein expression of COX-2, MMP-2, and MT1-MMP and the activity of MMP-2 and MMP-9 in BC patients. However, the enzymatic activity showed no correlation with clinicopathological features. This study confirms the preclinical evidence that COX-2 increased the expression of MT1-MMP, which in turn activates MMP-2. The lack of correlation with clinicopathological features, OS or disease-free survival ascertains the complexity of tumor progression and metastasis with many pro- and counter regulatory factors.  相似文献   
39.
Complex I in bovine heart submitochondrial particles catalyses the NADH-supported generation of superoxide anion; adrenaline is oxidised by superoxide to adrenochrome that, on its hand, is reduced by Complex I, thus establishing a redox cycle that amplifies the superoxide production. The routes in Complex I for superoxide formation and for adrenochrome reduction appear to be different, since they have a different sensitivity to Complex I inhibitors. The results are discussed in terms of current assays for superoxide detection and of pathologies linked to catecholamine oxidation.  相似文献   
40.

Background

Cutaneous leishmaniasis (CL) is a neglected tropical disease endemic in the tropics and subtropics with a global yearly incidence of 1.5 million. Although CL is the most common form of leishmaniasis, which is responsible for 60% of DALYs lost due to tropical-cluster diseases prevalent in Yemen, available information is very limited.

Methodology/Principal Findings

This study was conducted to determine the molecular characterization of Leishmania species isolated from human cutaneous lesions in Yemen. Dermal scrapes were collected and examined for Leishmania amastigotes using the Giemsa staining technique. Amplification of the ribosomal internal transcribed spacer 1(ITS-1) gene was carried out using nested PCR and subsequent sequencing. The sequences from Leishmania isolates were subjected to phylogenetic analysis using the neighbor-joining and maximum parsimony methods. The trees identified Leishmania tropica from 16 isolates which were represented by two sequence types.

Conclusions/Significance

The predominance of the anthroponotic species (i.e. L. tropica) indicates the probability of anthroponotic transmission of cutaneous leishmaniasis in Yemen. These findings will help public health authorities to build an effective control strategy taking into consideration person–to-person transmission as the main dynamic of transmission of CL.  相似文献   
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