PSII photochemistry and antioxidant responses of a chickpea variety exposed to drought

The effect of drought on the chickpea variety ILC 3279 was investigated at the vegetative stage. After 20 days from sowing, the plants subjected to drought stress for 3, 5 and 7 days imposed by withholding water were permitted to recover by rewatering for 2 days after 3, 5 and 7 days of drought. Shoot elongation, leaf production, fresh and dry biomass reduced while MDA and proline accumulation increased with extended duration of stress. The plants stressed for 3 days exhibited a rapid drop in their relative and absolute water contents. The quantum efficiency of PSII open centres in the dark-adapted and light-saturated state, excitation energy trapping of PSII and electron transport rate decreased significantly from the 5th day to the end of the drought treatments. Plants drought-stressed for 7 days brought about a marked increase in non-photochemical energy dissipation and a marked decline in photochemical quenching. After rewatering all chlorophyll a fluorescence characteristics except for F(M) completely recovered and reached the control values. Under 5 and 7 days of drought, the anthocyanin content increased gradually while the total chlorophyll content of leaves declined compared to the controls. The total carotenoid content remained unchanged during the experiments. The antioxidant enzyme response to drought treatments was quite variable. The total SOD activity upregulated with increasing duration of stress. On the other hand, the total APX activity was significantly higher only on the 7th day while the total POD activity increased from the 5th day. Differences in the total GR activity of treated groups were not statistically significant compared to their controls throughout the treatments. The present results indicate that the chickpea variety ILC 3279 withstands severe drought with its upregulated protective mechanisms at the vegetative stage.     

Leukotriene D4 receptor antagonist montelukast alleviates water avoidance stress-induced degeneration of the gastrointestinal mucosa

We investigated the role of montelukast (ML), a cysteinyl leukotriene-1 receptor antagonist, on the water avoidance stress (WAS)-induced degeneration of the rat gastric, ileal and colonic mucosa. One group of Wistar albino rats were exposed to chronic WAS (WAS group) 2h daily for 5 days. Another group was administered ML (10mg/kg; i.p.; WAS+ML group) following every WAS exposure for 5 days. Control rats were injected with the vehicle solution only. The stomach, ileum and colon were dissected and investigated for histopathological changes with a light microscope as well as for topographical changes with a scanning electron microscope. The levels of malondialdehyde (MDA, a biomarker of oxidative damage) and glutathione (GSH, a biomarker of protective oxidative injury) were also determined in all dissected tissues. In the WAS group, the stomach epithelium showed ulceration in some areas, dilatations of the gastric glands, degeneration of gastric glandular cells, and prominent congestion of the capillaries. In a similar fashion, degenerated epithelium and severe vascular congestions were observed in the ileum and colon. In all the tissues dense inflammatory cell infiltration and mast cell degranulation in mucosa were observed. The levels of MDA were significantly increased whereas those of GSH were significantly decreased in all test tissues in the WAS group compared to the control group. The morphology of gastric, ileal and colonic mucosa in WAS+ML group showed a significant amelioration showing a reduction in inflammatory cell infiltration and mast cell degranulation. Increased MDA and decreased GSH levels in the WAS group were also ameliorated with ML treatment. Based on the results, ML supplement seems attenuated inflammatory effects of WAS induction in gastrointestinal mucosa.     

Immobilization of catalase via adsorption onto -histidine grafted functional pHEMA based membrane

Poly(2-hydroxyethylmethacrylate) (pHEMA) based flat sheet membrane was prepared by UV-initiated photopolymerization technique. The membrane was then grafted with -histidine. Catalase immobilization onto the membrane from aqueous solutions containing different amounts of catalase at different pH was investigated in a batch system. The maximum catalase immobilization capacity of the pHEMA–histidine membrane was 86 μg cm⁻². The activity yield was decreased with the increase of the enzyme loading. It was observed that there was a significant change between V_max value of the free catalase and V_max value of the adsorbed catalase on the pHEMA–histidine membrane. The K_m value of the immobilized enzyme was higher 1.5 times than that of the free enzyme. Optimum operational temperature was 5°C higher than that of the free enzyme and was significantly broader. It was observed that enzyme could be repeatedly adsorbed and desorbed without loss of adsorption capacity or enzyme activity.     

Immunohistochemistry of matrix metalloproteinases (MMP), their substrates, and their inhibitors (TIMP) during trophoblast invasion in the human placenta

The invasion of extravillous trophoblast cells into the maternal endometrium is one of the key events in human placentation. The ability of these cells to infiltrate the uterine wall and to anchor the placenta to it as well as their ability to infiltrate and to adjust utero-placental vessels to pregnancy depends, among other things, on their ability to secrete enzymes that degrade the extracellular matrix. Most of the latter enzymes belong to the family of matrix metalloproteinases. Their activity is regulated by the tissue inhibitors of matrix metalloproteinases. We have studied the distribution patterns of matrix metalloproteinases-1, -2, -3, and -9 and their inhibitors TIMP-1 and TIMP-2 as compared to the distribution of their substrates along the invasive pathway of extravillous trophoblast of 1st, 2nd, and 3rd trimester placentas by means of light microscopy on paraffin and cryostat sections as well as at the ultrastructural level (only 3rd trimester placenta). The comparison of different methods proved to be necessary, since the immunohistochemical distribution patterns of these soluble enzymes are considerably influenced by the pretreatment of tissues. All three methods revealed immunoreactivities of both, proteinases and their inhibitors, not only intracellularly in the extravillous trophoblast but also extracellularly in its surrounding matrix, the distribution patterns depending on the stage of pregnancy and on the degree of differentiation of trophoblast cells along their invasive pathway. Within the extracellular matrix, immunolocalization of matrix metalloproteinases as well as their inhibitors showed a specific relation to certain extracellular matrix molecules.     

Prevalence of known mutations in the MEFV gene in a population screening with high rate of carriers

The Familial Mediterranean Fever (FMF) shows an autosomal recessive pattern of inheritance and affects certain ethnic groups. Disease is caused by mutations in MEFV gene and more than 180 mutations have been defined in affected individuals. Current study aimed to determine the frequency-type of the mutations for MEFV gene in Sivas??middle Anatolian city. The cohort was composed of 3340 patients. MEFV gene mutations were studied by multiplex PCR based reverse hybridization stripAssay method. Patients?? clinical features were; family history: 68%, erysipelas-like erythema: 17.6%, fever: 89.9%, abdominal pain: 84.2%, peritonitis: 90.2%, arthritis: 33%, pleuritis: 14.2%, parental consanguinity: 21.2%. Current results revealed that M694V is the most frequent mutation (43.12%), followed by E148Q (20.18), M680I(G/C) (15.00%) and V726A (11.32%). The study population has a high rate of carriers and the E148Q mutation frequency was found to be highest when compared to the other regions of Turkey and other Mediterranean groups.     

A Discriminant Analysis of Trace Elements in Scalp Hair of Healthy Controls and Stage-IIIB Non-small Cell Lung Cancer (NSCLC) Patients

Our work aimed at extending the search for the trace elements (TE) abnormalities in patients with lung cancer and in healthy controls who smoke, and also for evidence of a possible association between lung cancer and TE. The analysis of the hair from patients with Stage-IIIB non-small cell lung cancer (group 1) and healthy controls (group 2) were analyzed using the inductively coupled plasma mass spectrometry technique in order to obtain information on the correlation between the lung cancer patients and healthy controls. Sixty-seven one-hair samples in group 1 were individually collected before chemoradiotherapy. For comparison, 74 hair samples were collected from group 2. In group 1, the trace elements present at the highest levels were measured to be Ca, Zn, Sn, Na and Mg, respectively, and they were quantified as 68.2, 53.2, 33.9, 23.3, and 28.9?μg.kg(-1), respectively. In group 2, the trace elements present at the highest levels were Zn, Mg, Ca, Fe, and Se, respectively, and they were quantified as 109.7, 31.9, 30.8, 25.0, and 20.1?μg.kg(-1). In group 1, the highest levels of Ca, Sn, and Na were 2.03, 1.06, and 1.01 times higher, respectively, compared with group 2. In group 2, Zn, Mg, Fe, and Se were 2, 1.01, 2.7, and 1.6 times higher, respectively, compared with group 1. When the levels of trace elements were compared between groups 1 and 2 using Student's t test, the levels of Ag, Au, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Fe, Ga, Hg, K, Ni, Rb, Rh, Sb, Sc, Ti, V, and Zn were found to be statistically different (p?相似文献   

The influence and the mechanism of docosahexaenoic acid on a mouse model of Parkinson's disease

This study aimed to investigate the effects of docosahexaenoic acid (DHA) on the oxidative stress that occurs in an experimental mouse model of Parkinson’s disease (PD). An experimental model of PD was created by four intraperitoneal injections of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (4 × 20 mg/kg, at 12 h intervals). Docosahexaenoic acid was given daily by gavage for 4 weeks (36 mg/kg/day). The motor activity of the mice was evaluated via the pole test, and the dopaminergic lesion was determined by immunohistochemical analysis for tyrosine hydroxylase (TH)-immunopositive cells. The activity of antioxidant enzymes in the brain were determined by spectrophotometric assays and the concentration of thiobarbituric acid-reactive substances (TBARS) were measured as an index of oxidative damage. The number of apoptotic dopaminergic cells significantly increased in MPTP-treated mice compared to controls. Although DHA significantly diminished the number of cell deaths in MPTP-treated mice, it did not improve the decreased motor activity observed in the experimental PD model. Docosahexaenoic acid significantly diminished the amount of cell death in the MPTP + DHA group as compared to the MPTP group. TBARS levels in the brain were significantly increased following MPTP treatment. Glutathione peroxidase (GPx) and catalase (CAT) activities of brain were unaltered in all groups. The activity of brain superoxide dismutase (SOD) was decreased in the MPTP-treated group compared to the control group, but DHA treatment did not have an effect on SOD activity in the MPTP + DHA group. Our current data show that DHA treatment exerts neuroprotective actions on an experimental mouse model of PD. There was a decrease tendency in brain lipid oxidation of MPTP mice but it did not significantly.     

The Usefulness of DNA Sequencing After Extraction by Whatman FTA Filter Matrix Technology and Phenotypic Tests for Differentiation of Candida albicans and Candida dubliniensis

Since C. dubliniensis is similar to C. albicans phenotypically, it can be misidentified as C. albicans. We aimed to investigate the prevalence of C. dubliniensis among isolates previously identified as C. albicans in our stocks and to compare the phenotypic methods and DNA sequencing of D1/D2 region on the ribosomal large subunit (rLSU) gene. A total of 850 isolates included in this study. Phenotypic identification was performed based on germ tube formation, chlamydospore production, colony colors on chromogenic agar, inability of growth at 45 °C and growth on hypertonic Sabouraud dextrose agar. Eighty isolates compatible with C. dubliniensis by at least one phenotypic test were included in the sequence analysis. Nested PCR amplification of D1/D2 region of the rLSU gene was performed after the fungal DNA extraction by Whatman FTA filter paper technology. The sequencing analysis of PCR products carried out by an automated capillary gel electrophoresis device. The rate of C. dubliniensis was 2.35 % (n = 20) among isolates previously described as C. albicans. Consequently, none of the phenotypic tests provided satisfactory performance alone in our study, and molecular methods required special equipment and high cost. Thus, at least two phenotypic methods can be used for identification of C. dubliniensis, and molecular methods can be used for confirmation.