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101.
DuBois Arthur B.; Kelley Patrick M.; Douglas James S.; Mohsenin Vahid 《Journal of applied physiology》1999,86(1):159-167
Different volumesof dead-space gas were collected and analyzed for nitric oxide (NO)content, either immediately after inspiration or after a period ofbreath holding on clean air or NO mixtures. This allowed calculation ofNO equilibrium, NO production, and NO absorption. In seven young,healthy, adult nonsmokers, the mean NO equilibrium values in parts perbillion (ppb) were 56 ± 11 (SE) in the trachea, 37 ± 6 in thebronchi, 21 ± 3 in the bronchioles, and 16 ± 2 in therespiratory bronchioles. At any given NO concentration, the NOabsorption rate (in nl/min) equaled the NO concentration (in ppb) timesA (the absorption coefficient inl/min). A values (in l/min) were 0.11 ± 0.01 in the trachea, 0.17 ± 0.04 in the bronchi, 0.66 ± 0.09 in the bronchioles, and 1.35 ± 0.32 in the respiratorybronchioles. NO equilibrium concentrations and production rates in one74-yr-old subject were three to five times as high as those found inthe young subjects. Mouth equilibrium NO concentrations were 3 and 6 parts per million in two subjects who had oral production rates of 6 and 23 nl/min, respectively. In conclusion, production and absorptionof NO occur throughout the first 450 ml of the airways. 相似文献
102.
Essam Abdel-Salam Shaalan Deon Vahid Canyon Reinhold Muller Mohamed Wagdy Faried Younes Hoda Abdel-Wahab Abdel-Hamid Mansour 《Journal of vector ecology》2007,32(1):16-21
A twelve-month survey for mosquito predators was conducted in Townsville, Queensland, Australia, which is located in the arid tropics. The survey revealed the presence of five predaceous insects but only Anisops sp. (backswimmers) and Diplonychus sp. were common. Predatorial capacity and factors influencing this capacity were then assessed for adult Anisops sp. and adult and nymph stages of Diplonychus sp. against Culex annulirostris mosquito immatures under laboratory conditions. Predatorial capacity bioassays showed that adult Diplonychus sp. preyed upon both larval and pupal stages of Cx. annulirostris quite successfully. Nymphs of Diplonychus sp. proved to be more successful with smaller prey immatures, and Anisops sp adults did not prey successfully on any prey pupae. Increasing the foraging area and introducing aquatic vegetation significantly reduced the predatorial capacity of Diplonychus sp. nymphs, while only vegetation and not foraging area had a significant effect on adult Diplonychus sp. predation capacity. Overall, adult Diplonychus sp. proved to be a more efficient predator than Anisops sp., and field trials are now recommended to further assess the potential of Diplonychus sp. as a biocontrol agent. 相似文献
103.
Sahar Khajeh Vahid Razban Tahereh Talaei-Khozani Masoud Soleimani Reza Asadi-Golshan Farzaneh Dehghani Amin Ramezani Zohreh Mostafavi-Pour 《Biologia》2018,73(7):715-726
High incidence of articular cartilage defects resulting from age-related degeneration or trauma injuries is a major problem worldwide. Limited self-regeneration ability of cartilage often leads to inappropriate biochemistry and structure of healed tissue. Considering Impairments of traditional treatments, cell-based therapies are promising. The rapid ex vivo expansion and chondrogenic differentiation capability make dental pulp stem cells (DPSCs) a favorable cell type for therapeutic application, however strategies in order to efficient cartilage tissue-like production are imperative. In the present study the potential role of hypoxia mimicking agent, cobalt chloride (CoCl2), on chondrogenic differentiation of human DPSCs was surveyed. Cell viability assay used to obtain the optimum dose and exposure time of CoCl2. DPSCs were differentiated in pellet culture system after CoCl2 pretreatment. Chondrogenic differentiation efficiency was evaluated by histological and immunohistological analyses. The results showed that CoCl2 led to increased pellet size, integrity and matrix deposition with organizations more resembled typical cartilage lacuna structure. Furthermore, CoCl2 could improve differentiation by elevated chondrogenic markers, glycosaminoglycans (GAGs) and collagen II expression. CoCl2 pretreatment mitigated hypertrophy, as well, which was reflected in decreased collagen X expression. Alkaline phosphatase (ALP) specific activity did not change significantly by CoCl2 preconditioning. Based on current study hypoxia mimicking agent, CoCl2, could be suggested to promote DPSCs chondrogenic differentiation. 相似文献
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107.
Vahid Jabbari Mahmoud Sowti Khiabani Reza Rezaei Mokarram Azad Mohammad Hassanzadeh Elham Ahmadi Sasan Gharenaghadeh Nayyer Karimi Hossein Samadi Kafil 《Probiotics and antimicrobial proteins》2017,9(2):189-193
The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains. 相似文献
108.
Mohammad Reza Afarinesh Vahid Sheibani Somaye Arabzadeh Ali Shamsizadeh 《Addiction biology》2008,13(1):31-39
Chronic exposure to morphine can impair performance in tasks which need sensory processing. Using single unit recordings we investigate the effect of chronic morphine exposure on the firing properties of neurons in layers IV and V of the whisker-related area of rat primary somatosensory cortex. In urethane-anesthetized animals, neuronal activity was recorded in response to principal and adjacent whisker deflections either stimulated independently or in a conditioning test paradigm. A condition test ratio (CTR) was calculated for assessing the inhibitory receptive field. In layer IV, chronic morphine treatment did not change the spontaneous discharge activity. On responses to principal and adjacent whisker deflections did not show any significant changes following chronic morphine exposure. The magnitude Off responses to adjacent whisker deflection decreased while its response latency increased. In addition, there was a significant increase in the latency of Off responses to principal whisker deflection. CTR did not change significantly following morphine exposure. Layer V neurons, on the other hand, did not show any significant changes in their spontaneous activity or their evoked responses following morphine exposure. Our results suggest that chronic morphine exposure has a subtle modulatory effect on response properties of neurons in barrel cortex. 相似文献
109.
Hadi Mozafari Zohreh Rahimi Azadeh Heidarpour Mahsa Fallahi Adraiana Muniz 《Molecular biology reports》2009,36(8):2361-2364
It has been suggested that the allele frequency of thrombophilic mutations is affected by glucose-6-phosphate dehydrogenase
(G6PD) deficiency. The prevalence of thrombophilic mutations were studied in sixty G6PD deficient individuals including 57
males and three females with the mean age of 15 ± 3.08 and 110 age and sex matched healthy individuals consisted of 95 males and 15 females with
the mean age of 16.19 ± 2.17 from the Kermanshah Province of Iran. Using a combination of PCR-RFLP technique, single strand
conformation polymorphism (SSCP) analysis and DNA sequencing polymorphic G6PD mutations were identified. The factor V Leiden,
prothrombin G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T were detected by PCR-RFLP method using MnlI, HindIII
and HinfI restriction enzymes, respectively. Three mutations, G6PD Mediterranean, G6PD Chatham and G6PD Cosenza were identified
in 60 G6PD deficient individuals with highest prevalence of G6PD Mediterranean (91.6%). In G6PD deficient individuals the
prevalence of factor V Leiden tended to be higher (5%) compared to healthy individuals (2.7%). The prevalence of prothrombin
G20210A mutation in G6PD deficient individuals was 1.7%. However, in normal subjects the prevalence of this mutation was 2.7%.
The frequency of T allele in G6PD deficient individuals were insignificantly higher (29.16%) than those in healthy individuals
(26.8%). Our finding indicates that the prevalence of factor V Leiden, prothrombin G20210A and MTHFR C677T in G6PD deficient
individuals is not statistically different compared to normal subjects and G6PD deficiency is not associated with these thrombophilic
mutations in Western Iran. 相似文献
110.
Vahid Molla Kazemiha Mohammad Ali Shokrgozar Mohammad Reza Arabestani Morteza Shojaei Moghadam Shahram Azari Susan Maleki Amir Amanzadeh Mahmood Jeddi Tehrani Fazel Shokri 《Cytotechnology》2009,61(3):117-124
A total of 200 cell lines including different human, monkey, mice, hamster and rat cell types were examined for mycoplasma
infection status. PCR assay using generic-specific universal primers showed that 40 (20%) of the cell lines are contaminated
with mycoplasma. Employment of species-specific primers within these infected cell lines revealed infection with M. hyorhinis (42.5%), M. fermentas (37.5%), M. arginini (37.5%), M. orale (12.5%) and A. laidlawii (7.5%). A number of the cultures were coinfected with 2 or 3 different species. Contaminated samples were treated with BM-Cyclin,
Ciprofloxacin and mycoplasma removal agent (MRA). Mycoplasma eradication was subsequently checked by PCR following 2 weeks
continuous culture of treated cells in antibiotic free culture medium. Mycoplasmal infections were eradicated in 100, 70 and
42% of infected cell lines when the samples were treated with BM-Cyclin, MRA and Ciprofloxacin, respectively. However, 12%
(BM-Cyclin), 62.5% (MRA) and 82.5% (Ciprofloxacin) of mycoplasma regrowth was observed 4 months after the treatment. Notably,
the risk of spontaneous culture death was 17.5, 12.5 and 0% for BM-Cyclin, MRA and Ciprofloxacin, respectively. 相似文献