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21.

Background:

Cutaneous leishmaniasis is one of the most important parasitic diseases in humans. In this disease, one of the responsible organisms is Leishmania major, which is transmitted by sandfly vector. There are specific differences in biochemical profiles and metabolite pathways in logarithmic and stationary phases of Leishmania parasites. In the present study, 1H NMR spectroscopy was used to examine the metabolites outliers in the logarithmic and stationary phases of promastigotes in L. major to enlighten more about the transmission mechanism in metacyclogenesis of L. major.

Methods:

Promastigote was cultured, logarithmic and stationary phases were separated by the peanut agglutinin, and cell metabolites were extracted. 1H NMR spectroscopy was applied, and outliers were analyzed using principal component analysis.

Results:

The most altered metabolites in stationary and logarithmic phases were limited to citraconic acid, isopropylmalic acid, L-leucine, ornithine, caprylic acid, capric acid, and acetic acid.

Conclusion:

1H NMR spectroscopy could play an important role in the characterization of metabolites in biochemical pathways during a metacyclogenesis process. These metabolites and their pathways can help in exploiting a transmission mechanism in metacyclogenesis, and outcoming data might be used in the metabolic network reconstruction of L. major modeling. Key Words: Leishmania major, Metabolomics, Principal component analysis  相似文献   
22.
Drought is a worldwide concern and designation of drought stress adaptive mechanisms is one of the main directions in plant physiology and crop breeding. Genotypes diversity can be used to identify effective unexploited genes and pathways. In order to that, the effect of varying terminal drought intensity treatments on physiological and biochemical traits was evaluated in ILC3279, ICCV2 and FLIP9855 C chickpea lines. Well-watered, intermediate and severe drought treatments were applied from flowering till maturity. Photosynthetic efficiency, membrane stability, soluble sugar and proline content, leaf protein profile, and antioxidant enzyme activities were compared on 1st, 3rd, and 5th week after applying stress. Based on the results, it was found that the susceptibility of photosynthetic machinery of ILC3279 was more than others. Tolerant genotypes responded to drought differently; an increase and a decrease in catalase activity have been observed in ICCV2 and FLIP9855 C, respectively. The prominent role of soluble sugars was observed in ICCV2. Expressions of polypeptides 27 and 45 kDa in tolerant lines refer to their possible role in drought stress adaptation. Generally, in spite of significant variability in chickpea lines to cope with drought, lower ascorbate peroxidase activity, higher peroxidase activity, and higher Fv/Fm ratio can be tested as markers of chickpea drought tolerant.  相似文献   
23.
AIMS: To retrospectively evaluate the medical and surgical records of horses with acute small intestinal obstructions associated with Parascaris equorum infection; to describe the gastrointestinal lesions; and to determine the outcome of cases with such lesions.

METHODS: Records of 25 horses with acute small intestinal obstruction associated with P. equorum between 1985 and 2004 were reviewed to determine signalment, history, physical examination, surgical or post-mortem findings, and outcome.

RESULTS: All horses except one were less than 12 months old. Standardbreds were over-represented in the population studied. Sixteen horses (72%) had been administered anthelmintics, including pyrantel (n=8), ivermectin (n=7), and trichlorphon (n=1), within 24 h prior to the onset of colic. Of the 25 cases reviewed, 16 had simple obstructive ascarid impactions (SOAIs), and nine had complicated obstructive ascarid impaction (COAI) including volvulus (n=6) or intussusception (n=3), both concurrent with ascarid impaction of the small intestine. Short-term survival (discharge from hospital) occurred in 79% of horses treated for SOAI, and was 64% for all horses. Long-term survival (>1 year) occurred in 33% of horses with SOAI, and the overall long-term survival was 27% for all horses. Formation of adhesions was the most frequent finding associated with death for horses that did not survive long-term.

CONCLUSIONS AND CLINICAL RELEVANCE: The incidence of anthelmintic treatment within 24 h of the onset of colic in this study population (72%) was higher than that previously reported. Resistance of P. equorum to ivermectin recently reported in Ontario may be associated with increased ascarid burdens, predisposing horses to ascarid impaction. The long-term survival of these horses was better than that reported previously.  相似文献   
24.
Two experiments were carried out in 2013 and 2014, to investigate changes in grain filling rate (GFR), grain filling duration (GFD) and yield of mung bean in response to salicylic acid (SA) and silicon (Si) under salt stress (0, 3, 6 and 9 dS m?1). In experiment 1, four levels of SA (0, 0.5, 1 and 1.5 mM), but in experiment 2, two levels of SA (0 and 1 mM) and Si (0 and 2 mM) were applied. In experiment 1, GFR, GFD, yield components, biological and grain yields and harvest index were decreased with increasing salt stress. Application of different levels of SA, especially 1 mM, increased GFR, but decreased GFD. In experiment 2, GFD under salinity was shorter than that under non-saline condition, resulting in comparatively smaller grains. Application of Si and particularly SA accelerated grain development under all salinity treatments. The superiority of SA treated plants in GFR, grain weight and grains per plant resulted in greater grain yield per plant under saline and non-saline conditions.  相似文献   
25.
The comparative responses of certain biochemical and physiological characteristics to salinity were studied in 4 cultivars of sugar beet (Beta vulgaris L.) plants. Eight weeks old plants were treated with NaCl at 0, 25 and 50 mM in nutrient solutions. Plants were grown under controlled environment and harvested after 3 weeks for measurements of biochemical and physiological parameters. Results showed that in 25 mM NaCl for cultivars of ET5 and C3-3, soluble sugars in leaves, photosynthetic rate and growth parameters were significantly increased as compared to those of other cultivars. In 50 mM NaCl photosynthetic rate and soluble sugars were significantly increased only in ET5 cultivar as compared with those of others. Results indicated that in 25 mM NaCl, ET5 cultivar showed high growth responses and tolerated to 50 mM NaCl.  相似文献   
26.
Dinoflagellates are single-celled organisms that reflect the ecological conditions in modern oceans and lakes. Ultrastructural data and molecular phylogeny suggest that they originated in the Neoproterozoic, yet dinoflagellate ancestors are classified only to the Middle Triassic ( approximately 240 million years ago). Examination of dinoflagellate-specific biological markers (dinosteranes and 4alpha-methyl-24-ethylcholestane) in concentrated microfossils with known morphology identified ancient dinoflagellate ancestors from the Early Cambrian ( approximately 520 million years ago).  相似文献   
27.
BACKGROUND: Evidence supports the involvement of nitric oxide (NO) in a variety of male reproductive processes such as spermatogenesis, spermiogenesis, sperm motion, sperm metabolism and sperm capacitation. However, low concentration of NO is essential in biology and physiology of spermatozoa, but high amounts of NO is toxic and has negative effects on sperm functions. On the other hand, it is established that high amounts of NO have detrimental effects on DNA. The integrity of sperm DNA is an important factor in successful fertility and embryo development. It is hypothesized that supra physiological concentrations of NO in seminal plasma cause sperm DNA damage. The aim of this study was to determine sperm DNA damage by comet assay and its correlation with NO level in seminal plasma of fertile and infertile men. METHODS: Semen samples were collected from 45 patients and 70 healthy donors. The stable metabolites of NO (nitrite and nitrate) in seminal plasma were measured by Griess assay and DNA damage was determined using single cell gel electrophoresis (comet) assay method. RESULTS: The NO concentration in the seminal plasma of infertile males was significantly higher than fertile males (5.74+/-1.01 microM/L vs. 3.88+/-0.53 microM/L). There was a significant positive correlation between the NO concentration and sperm DNA comet value in infertile males (P<0.01, R=0.598). CONCLUSION: These results indicate that the overproduction of NO in genital tract of infertile males has a potential pathogenetic role in the reduction of sperm DNA integrity.  相似文献   
28.
In this paper, poly(amido primary-secondary amine) (PAPSA) as a high capacity polymeric adsorbent was synthesized. Dye removal ability of PAPSA from single and binary systems was investigated. The functional groups of PAPSA were studied using Fourier transform infrared (FTIR). Acid Blue 92 (AB92), Direct Red 23 (DR23), and Direct Red 81 (DR81) were used as model compounds. The kinetic and isotherm of dye adsorption were studied. The effect of operational parameter such as adsorbent dosage, dye concentration, and pH on dye removal was evaluated. It was found that adsorption of dyes onto PAPSA showed Langmuir isotherm. The maximum dye adsorption capacity (Q 0) of PAPSA was 10000 mg/g, 12500 mg/g, and 10000 mg/g for AB92, DR23, and DR81, respectively. Adsorption kinetic of dyes followed pseudo-second order kinetics. Dye desorption tests showed that the dye release of 85 % for AB92, 91 % for DR23 and 89 % for DR81 were achieved in aqueous solution at pH 12. The results showed that the PAPSA as a polymeric adsorbent with high dye removal ability might be a suitable alternative to remove dyes from colored wastewater.  相似文献   
29.
The present study sought to determine: (i) the effects of Neospora caninum infection and twin pregnancy on plasma pregnancy‐associated glycoprotein‐2 (PAG‐2) concentrations throughout pregnancy and (ii) whether plasma PAG‐2 concentrations could predict abortion in N. caninum‐infected cows. The study was performed on a commercial Holstein‐Friesian dairy herd in northeastern Spain and the final data included those recorded in 53 non‐aborting and 19 aborting animals. Blood samples were collected immediately before pregnancy diagnosis (on Days 40, 90, 120, 150, 180 and 210 post‐insemination) in non‐aborting cows or until the time of abortion detection in aborting cows. General lineal models (GLM) repeated measures anova revealed the different behaviour of PAG‐1 and PAG‐2, and significant effects of Neospora seropositivity, cool season and twin pregnancy on plasma PAG‐2 concentrations throughout gestation (between‐subject effects). In addition, based on the odds ratios, the likelihood of abortion increased in Neospora‐seropositive cows (by a factor of 7.0) compared to seronegative animals and decreased in cows with a high plasma PAG‐2 concentration (>4.5 ng/ml) on Day 120 of pregnancy (by a factor of 0.24), compared to the remaining cows. In conclusion, there is a relationship between plasma PAG‐2 concentrations and the risk of abortion in Neospora‐infected dairy cows. Thus, plasma PAG concentrations measured using anti‐boPAG‐2 antiserum on Day 120 of gestation could serve as an indicator of the abortion risk in N. caninum infected animals; values <4.5 ng/ml indicating a high risk of abortion in chronically infected animals.  相似文献   
30.
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