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41.
The involvement of chloride in salt stress symptoms and salt tolerance mechanisms in plants has been less investigated in the past. Therefore, we studied the salt-induced chloride influx in Arabidopsis expressing the GFP-based anion indicator Clomeleon. High salt concentrations induce two phases of chloride influx. The fast kinetic phase is likely caused by membrane depolarization, and is assumed to be mediated by channels. This is followed by a slower "saturation" phase, where chloride is accumulated in the cytoplasm. Both phases of chloride uptake are dependent on the presence of external calcium. In general: with high [Ca2+] less chloride is accumulated in the cytoplasm. Surprisingly, also the internal calcium availability has an impact on chloride transport. A complete block of the second phase of chloride influx is achieved by the anion channel blocker A9C and trivalent cations (La3+, Gd3+, and Al3+). Other channel blockers and diuretics were found to inhibit the process partially. The results suggest that several transporter species are involved here, including electroneutral cation-chloride-cotransporters, and a part of chloride possibly enters the cells through cation channels after salt application. 相似文献
42.
Saleh Ahmed A. Eltantawy Mohammed S. Gawish Esraa M. Younis Hassan H. Amber Khairy A. Abd El-Moneim Abd El-Moneim E. Ebeid Tarek A. 《Biological trace element research》2020,195(2):506-514
Biological Trace Element Research - The objectives of this study were to investigate the impact of dietary organic mineral mixture (manganese, zinc, and copper) supplementation on reproductive... 相似文献
43.
Dkhil Mohamed A. Abdel Moneim Ahmed E. Bauomy Amira A. Khalil Mona Al-Shaebi Esam M. Al-Quraishy Saleh 《Molecular biology reports》2020,47(2):1161-1171
Molecular Biology Reports - Arsenic is a potent and toxic heavy metal found in the environment that causes health problems, including liver disease, in humans and animals. Chlorogenic acid (CA) is... 相似文献
44.
The consequence of harvesting young leaves of cassava as vegetable on the vulnerability of the crop to cassava mosaic disease (CMD) and on storage root yield was investigated using 30 cassava genotypes planted in IITA fields located in the humid forest (Port Harcourt?:?Onne), forest-savannah transition (Ibadan), southern guinea savannah (Mokwa) and northern guinea savannah (Zaria) agroecologies in Nigeria. Tender apical leaves and shoots of the cassava genotypes were removed from forty plants per cassava genotype with the same number of plants considered as control. Whitefly infestation, disease incidence (DI) and symptom severity (ISS) of the disease were assessed at monthly interval for six months and also at the ninth month after planting (MAP). Yield reduction due to this treatment was calculated as percentage harvest index (HI). Whitefly population fluctuated throughout the period of observation at all locations with higher population obtained generally for treated plants compared to control plants. Sprouting leaves of some treated genotypes were observed with severe mosaic symptoms, while corresponding control showed no mosaic symptoms. Contrarily, no remarkable difference was observed in Zaria between the mean ISS of treated and control cassava genotypes. There was a highly significant difference (P?<?0.01) in DI and ISS among cassava genotypes across all locations. Also, there was a highly significant interaction (P?<?0.01) in symptom severity between location (loc) and genotype, genotype and treatment (trt), loc and trt. Interaction between loc, genotypes and trt with regard to DI was highly significant at 2, 3 and 4 MAP, while with ISS, the interaction was highly significant all through the counting period. There was a positive relationship between DI and ISS on plants of genotypes 96/1039 and ISU. The percentage HI (27.4) of treated plants of genotype 95/0166 in Ibadan was remarkably lower than the value obtained for corresponding control (41.9) plants. Also, sharp distinction in% HI of treated (39.5) and control (43.8) ISU was observed in Onne with their respective ISS values as 3.7 and 3.2. Therefore, harvesting tender apical leaves and shoots of cassava as vegetables should be discouraged as it increases the severity of CMD infection in the regenerating shoots of cassava with attendant storage root yield reduction. 相似文献
45.
46.
In the absence of base-pairing and tertiary structure, ribonucleic acid (RNA) assumes a random-walk conformation, modulated by the electrostatic self-repulsion of the charged, flexible backbone. This behavior is often modeled as a Kratky-Porod “wormlike chain” (WLC) with a Barrat-Joanny scale-dependent persistence length. In this study we report measurements of the end-to-end extension of poly(U) RNA under 0.1 to 10 pN applied force and observe two distinct elastic-response regimes: a low-force, power-law regime characteristic of a chain of swollen blobs on long length scales and a high-force, salt-valence-dependent regime consistent with ion-stabilized crumpling on short length scales. This short-scale structure is additionally supported by force- and salt-dependent quantification of the RNA ion atmosphere composition, which shows that ions are liberated under stretching; the number of ions liberated increases with increasing bulk salt concentration. Both this result and the observation of two elastic-response regimes directly contradict the WLC model, which predicts a single elastic regime across all forces and, when accounting for scale-dependent persistence length, the opposite trend in ion release with salt concentration. We conclude that RNA is better described as a “snakelike chain,” characterized by smooth bending on long length scales and ion-stabilized crumpling on short length scales. In monovalent salt, these two regimes are separated by a characteristic length that scales with the Debye screening length, highlighting the determining importance of electrostatics in RNA conformation. 相似文献
47.
Jason D. Downey Sam A. Saleh Thomas M. Bridges Ryan D. Morrison J. Scott Daniels Craig W. Lindsley Richard M. Breyer 《Bioorganic & medicinal chemistry letters》2013,23(1):37-41
Recent preclinical studies demonstrate a role for the prostaglandin E2 (PGE2) subtype 1 (EP1) receptor in mediating, at least in part, the pathophysiology of hypertension and diabetes mellitus. A series of amide and N-acylsulfonamide analogs of a previously described picolinic acid-based human EP1 receptor antagonist (7) were prepared. Each analog had improved selectivity at the mouse EP1 receptor over the mouse thromboxane receptor (TP). A subset of analogs gained affinity for the mouse PGE2 subtype 3 (EP3) receptor, another potential therapeutic target. One analog (17) possessed equal selectivity for EP1 and EP3, displayed a sufficient in vivo residence time in mice, and lacked the potential for acyl glucuronide formation common to compound 7. Treatment of mice with 17 significantly attenuated the vasopressor activity resulting from an acute infusion of EP1 and EP3 receptor agonists. Compound 17 represents a potentially novel therapeutic in the treatment of hypertension and diabetes mellitus. 相似文献
48.
Jiamei Jiang Jie Huang Liqiong Li Chen Shao Khaled A.S. Al-Rasheid Saleh A. Al-Farraj Zigui Chen 《European journal of protistology》2013,49(1):78-92
The morphology, ontogeny and molecular phylogeny of Apobakuella fusca gen. n., sp. n. and Parabistichella variabilis gen. n., sp. n., from south China were investigated. Apobakuella fusca, brown colored, demonstrates bakuellid-like infraciliature, and a similar ontogenesis as the genus Bakuella. It is argued, however, that this species represents a novel genus, Apobakuella, which is characterized by two or more marginal rows on the right, several buccal and parabuccal cirri, and lack of frontoterminal and caudal cirri. Phylogenetic analysis based on SSU rRNA gene sequences supports the close relationship of Apobakuella with Neobakuella and Diaxonella within the core Urostylida. By contrast, Parabistichella variabilis has a dominant frontoventral row, few midventral pairs, a long midventral row, and one marginal row on each side. Its morphogenesis exhibits: (1) partial reorganization of the parental adoral membranelles; (2) over six frontoventral-transverse cirri anlagen; (3) intrakinetal development of the midventral row; and (4) very likely, formation of the frontoventral row from the midventral row anlage. Both the morphological characteristics and the SSU rRNA gene sequences suggest that it is incertae sedis among the basal hypotrichs. Further investigation of key taxa with additional molecular markers is required to reveal a better understanding on the phylogeny of Parabistichella. 相似文献
49.
Xinpeng Fan Xiaofeng Lin Weiwei Liu Yuan Xu Saleh A. Al-Farraj Khaled A.S. Al-Rasheid Alan Warren 《European journal of protistology》2013,49(2):312-323
Members of the ciliate genus Frontonia are common colonizers of periphytic communities in aquatic biotopes. Recent studies indicate that their species diversity is higher than previously supposed. In this study the morphology and infraciliature of three new species, Frontonia sinica spec. nov., F. pusilla spec. nov., and F. elegans spec. nov., isolated from coastal waters of China, were investigated using live observation and silver impregnation methods. Frontonia sinica differs from its congeners by the following combination of characters: ellipsoidal body, about 116 somatic and five or six vestibular kineties, peniculi 1 and 2 four-rowed, peniculus 3 two-rowed, and a single contractile vacuole. Frontonia pusilla has about 72 somatic kineties, four-rowed peniculi 1 and 2, a two-rowed peniculus 3, and two contractile vacuoles. Frontonia elegans has 73 somatic kineties, four-rowed peniculi 1 and 2, a three-rowed peniculus 3, and two contractile vacuoles. In the present work, six new small-subunit rRNA gene sequences of six Frontonia species are used to construct the phylogenetic trees. Our phylogenetic analysis supports that the genus Frontonia may be paraphyletic. Meanwhile, no pattern of correlation could be found between the structures of peniculi and the phylogenetic relationships of Frontonia species in the present study. 相似文献
50.
Wafaa M. Ezzat Yasser A. Elhosary Nour A. Abdulla Hala M. Raslan Omneya M. Saleh Mona H. Ibrahim Maha A. Rasheed H. El-Hariri 《Journal of Genetic Engineering and Biotechnology》2013,11(1):69-73
BackgroundStudies revealed that insulin resistance is associated with fibrosis progression and has negative impact on sustained virological response after standard antiviral therapy in patients with chronic hepatitis C (CHC).AimTo assess the role of IR on progression of liver fibrosis and early virological response (EVR) rates in patients with chronic hepatitis C infection.Patients and methodsThe study population comprised 79 subjects who underwent combination therapy for CHC. Laboratory investigations in the form of glucose, insulin, bilirubin, alanine aminotransferase (ALT), cholesterol and triglycerides and liver biopsy were done for all patients. Insulin resistance was calculated using the homeostasis model of IR (HOMA-IR).ResultsIR was increased (>2 IU) in 31 (40.7%) of patients. Early virological response was achieved among 37 patients (48.7%). No difference in EVR, viral load or grade of liver fibrosis between patients with and without IR. A significant positive correlation was found between IR and liver steatosis.ConclusionInsulin resistance is a common finding in CHC, it is associated with increase liver steatosis. However it has no impact on EVR to combined interferon ribavirin therapy, viral load or necroinflammation. 相似文献