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21.
(E)- and (Z)-1,2,4-triazolylchromanone oxime ethers as conformationally constrained antifungals 总被引:1,自引:0,他引:1
Emami S Falahati M Banifatemi A Amanlou M Shafiee A 《Bioorganic & medicinal chemistry》2004,12(15):3971-3976
A series of 1,2,4-triazolylchromanone oxime ethers were synthesized and tested for in vitro antifungal activity. Many of these derivatives exhibit high activity against Candida albicans, Saccharomyces cerevisiae, Aspergillus niger and Microsporum gypseum. 相似文献
22.
Intracellular Calcium: A Prerequisite for Aldosterone Action 总被引:1,自引:0,他引:1
Schäfer C Shahin V Albermann L Schillers H Hug MJ Oberleithner H 《The Journal of membrane biology》2003,196(3):157-162
23.
Two types of xylanase gene, XYN11A (XYL1) and XYN11B (XYL2), were amplified by PCR and partially sequenced in four phytopathogenic species of the ascomycete fungal genus Cochliobolus (anamorph genus Bipolaris). Three of the species, C. heterostrophus (B. maydis), C. sativus (B. sorokiniana), and Bipolaris sorghicola (no teleomorph known), are interrelated; the fourth, C. spicifer (B. spicifera), was found, through analysis of the 5.8S RNA and internal transcribed spacer (ITS) sequences of its ribosomal DNA, to be
more distantly related to the other three. Isolates from all four species contain orthologous XYN11A and XYN11B genes, but a set of laboratory strains of C. heterostrophus gave no product corresponding to the XYN11B gene. The patterns of evolution of the two xylanase genes and ribosomal DNA sequences are mutually consistent; the results
indicate that the two genes were present in the common ancestor of all Cochliobolus species and are evolving independently of each other.
Received: 12 July 2001 / Accepted: 6 March 2002 相似文献
24.
Hajizadeh S DeGroot J TeKoppele JM Tarkowski A Collins LV 《Arthritis research & therapy》2003,5(5):R234-R240
We investigated whether plasma and synovial fluid (SF) samples from patients with rheumatoid arthritis (RA) contained extracellular
mitochondrial DNA (mtDNA) or the oxidatively damaged DNA adduct 8-hydroxy-2'-deoxyguanosine (8-oxodG). Moreover, we correlated
the laboratory findings of the patients with RA with their levels of mtDNA and 8-oxodG. SF and plasma samples from 54 patients
with RA, SF from 30 non-arthritic control subjects, and plasma from 22 healthy volunteers were collected. The samples were
subjected to polymerase chain reaction (PCR) using mitochondrial genomic primers, and the products were analyzed by SDS–polyacrylamide-gel
electrophoresis. The intensities of the PCR-amplified bands were quantified and normalized to a reference sample. Furthermore,
the SF samples were assayed by enzyme-linked immunosorbent assay for 8-oxodG. Extracellular PCR-amplifiable mtDNA was detected
in the SF of 38 of 54 (70%) patients with RA, but not in any of the SF controls. PCR-amplifiable mtDNA was detected in the
plasma of 30 of 54 (56%) of patients with RA and in 6 of 22 (27%) of the healthy volunteers. The levels of mtDNA in the plasma
and SF samples of patients with RA were significantly higher (P < 0.0001) than in the respective control samples. The presence of both mtDNA and 8-oxodG in SF was significantly correlated
with the presence of rheumatoid factor in the patients with RA. Extracellular mtDNA and oxidized DNA were detected in the
SF of the great majority of patients with RA, but were absent or present at low levels in the control SF. These findings indicate
that endogenous nucleic acid compounds might participate in joint inflammation by activating immune cells in the joints to
produce proinflammatory cytokines. 相似文献
25.
Abdollahi M Bahreini-Moghadam A Emami B Fooladian F Zafari K 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2003,135(3):331-336
The effect of cadmium on induction of oxidative stress in rat submandibular saliva and protective role of increasing intracellular cAMP and cGMP by use of specific phosphodiesterase inhibitors, theophylline and sildenafil were investigated. Pure submandibular saliva was collected intraorally by micro polyethylene cannula from anaesthetized rats using pilocarpine as secretagogue. Acute administration of cadmium (10 mg/kg) caused significant oxidative stress by increasing lipid peroxidation by-products (thiobarbituric reactive substances, TBARS) and decreasing total thiols and total antioxidant power of the saliva. Concurrent therapy of rats by theophylline (25 mg/kg) and sildenafil (5 mg/kg) prevented cadmium-induced oxidative stress in saliva. Theophylline and sildenafil inhibited cadmium-induced increase in lipid peroxidation and decrease in total thiols and antioxidant power. It is concluded that cadmium administration results in oxidative stress in rat submandibular saliva, which can be protected by concurrent administration of specific cyclic nucleotide phosphodiesterase inhibitors. 相似文献
26.
Fungi belonging to the genus Coelomomyces can infect mosquito larvae and develop within the larval hemocoel. To examine fungal development, Aedesaegypti larvae infected with Coelomomyces stegomyiae Keilin were fixed, embedded and sectioned for both light and electron microscopy. While fungal hyphae of C. stegomyiae did not invade cells other than the cuticular epithelial cells, they did penetrate a number of tissues including muscles,
midgut, hemopoietic organ, imaginal discs, and Malpighian tubules.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
27.
Scott Dryden-Peterson Kara Bennett Michael D. Hughes Adrian Veres Oaitse John Rosina Pradhananga Matthew Boyer Carolyn Brown Bright Sakyi Erik van Widenfelt Koona Keapoletswe Madisa Mine Sikhulile Moyo Aida Asmelash Mark Siedner Mompati Mmalane Roger L. Shapiro Shahin Lockman 《PloS one》2015,10(2)
BackgroundLess than one-third of HIV-infected pregnant women eligible for combination antiretroviral therapy (ART) globally initiate treatment prior to delivery, with lack of access to timely CD4 results being a principal barrier. We evaluated the effectiveness of an SMS-based intervention to improve access to timely antenatal ART.MethodsWe conducted a stepped-wedge cluster randomized trial of a low-cost programmatic intervention in 20 antenatal clinics in Gaborone, Botswana. From July 2011-April 2012, 2 clinics were randomly selected every 4 weeks to receive an ongoing clinic-based educational intervention to improve CD4 collection and to receive CD4 results via an automated SMS platform with active patient tracing. CD4 testing before 26 weeks gestation and ART initiation before 30 weeks gestation were assessed.ResultsThree-hundred-sixty-six ART-naïve women were included, 189 registering for antenatal care under Intervention and 177 under Usual Care periods. Of CD4-eligible women, 100 (59.2%) women under Intervention and 79 (50.6%) women under Usual Care completed CD4 phlebotomy before 26 weeks gestation, adjusted odds ratio (aOR, adjusted for time that a clinic initiated Intervention) 0.87 (95% confidence interval [CI]0.47–1.63, P = 0.67). The SMS-based platform reduced time to clinic receipt of CD4 test result from median of 16 to 6 days (P<0.001), was appreciated by clinic staff, and was associated with reduced operational cost. However, rates of ART initiation remained low, with 56 (36.4%) women registering under Intervention versus 37 (24.2%) women under Usual Care initiating ART prior to 30 weeks gestation, aOR 1.06 (95%CI 0.53–2.13, P = 0.87).ConclusionsThe augmented SMS-based intervention delivered CD4 results more rapidly and efficiently, and this type of SMS-based results delivery platform may be useful for a variety of tests and settings. However, the intervention did not appear to improve access to timely antenatal CD4 testing or ART initiation, as obstacles other than CD4 impeded ART initiation during pregnancy. 相似文献
28.
Seyed Rasoul Hoseini Shahin Oustan Naser Aliasgharzad Norsatollah Najafi 《Soil & Sediment Contamination》2015,24(5):554-572
In this research, kinetics of Cr(VI) reduction by iron filings was investigated through a batch study in seven different soils. Chromate reduction experiments were carried out for initial Cr(VI) concentrations ranging from 20 to 100 mgkg?1 and iron filings dosage of 0 to 5% w/w. The experimental data were analyzed using various kinetic models including zero-order, pseudo first-order, power function, Elovich, and diffusion parabolic. Results showed that the Cr(VI) reduction efficiency in the presence of all studied soils increased with increasing iron filings dosage and decreased with increasing the initial Cr(VI) concentration. The reaction rates considerably depended on pH and were higher in acidic soils. The diffusion parabolic model was the best kinetic model as evidenced by the highest determination coefficient (r2) and the lowest standard error of the estimate (SE). The rate-limiting step(s) may be transport of chromate anions across a liquid film at the interface of soil-liquid, transport in liquid-filled macropores of iron filings aggregates, or diffusion in micropores and along the particle's surface. 相似文献
29.
Shahin Zarre Zeinab KhodaeiZahra Karamali Vahid NiknamMassoud Mirmasoumi 《Biochemical Systematics and Ecology》2007
Isoenzyme electrophoresis was employed to examine the relationships of 21 individuals representing four populations of Astragalus gossypinus complex as well as 20 individuals representing five populations of Astragalus persicus complex. A total of 27 bands from three enzyme systems (superoxide dismutase, esterase, and peroxidase) were obtained. UPGMA clustering method resulted in two distinct clusters for different populations corresponding to the two species complexes analysed. In both species, populations distributed on Alborz mountain range in northern Iran form separated clusters from those distributed on Zagros mountain range in the West. The results also show that both species complexes exhibit a high diversity based on Shannon–Weaver diversity index (H′) compared with other species of Astragalus reported previously. The mean number of bands per each presumed isoenzyme ranges from 2.14 to 3.57. The value of Euclidean distance ranges from 1.251 to 3.152. Our data suggest that both species should be circumscribed wider than that treated by most taxonomists, and several taxonomic names should be reduced under synonymy of the corresponding species. 相似文献
30.
Liashkovich I Hafezi W Kühn JM Oberleithner H Shahin V 《Journal of molecular recognition : JMR》2011,24(3):414-421
Herpes simplex virus type 1 (HSV-1) is a widespread human pathogen infecting more than 80% of the population worldwide. Its replication involves an essential, poorly understood multistep process, referred to as uncoating. Uncoating steps are as follows: (1) The incoming capsid pinpoints the nuclear pore complex (NPC). (2) It opens up at the NPC and releases the highly pressurized viral genome. (3) The viral genome translocates through the NPC. In the present review, we highlight recent advances in this field and propose mechanisms underlying the individual steps of uncoating. We presume that the incoming HSV-1 capsid pinpoints the NPC by hydrophobic interactions and opens up upon binding to NPC proteins. Genome translocation is initially pressure-driven. 相似文献