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91.
Aspergillus fumigatus, a ubiquitous human fungal pathogen, produces asexual spores (conidia), which are the main mode of propagation, survival and infection of this human pathogen. In this study, we present the molecular characterization of a novel regulator of conidiogenesis and conidial survival called MybA because the predicted protein contains a Myb DNA binding motif. Cellular localization of the MybA::Gfp fusion and immunoprecipitation of the MybA::Gfp or MybA::3xHa protein showed that MybA is localized to the nucleus. RNA sequencing data and a uidA reporter assay indicated that the MybA protein functions upstream of wetA, vosA and velB, the key regulators involved in conidial maturation. The deletion of mybA resulted in a very significant reduction in the number and viability of conidia. As a consequence, the ΔmybA strain has a reduced virulence in an experimental murine model of aspergillosis. RNA‐sequencing and biochemical studies of the ΔmybA strain suggested that MybA protein controls the expression of enzymes involved in trehalose biosynthesis as well as other cell wall and membrane‐associated proteins and ROS scavenging enzymes. In summary, MybA protein is a new key regulator of conidiogenesis and conidial maturation and survival, and plays a crucial role in propagation and virulence of A. fumigatus.  相似文献   
92.
The velvet factor of the homothallic fungus Aspergillus nidulans promotes sexual fruiting body formation. The encoding veA gene is conserved among fungi, including the ascomycete Neurospora crassa. There, the orthologous ve-1 gene encodes a deduced protein with high similarity to A. nidulans VeA. Cross-complementation experiments suggest that both the promoter and the coding sequence of N. crassa ve-1 are functional to complement the phenotype of an A. nidulans deletion mutant. Moreover, ve-1 expression in the heterologous host A. nidulans results in development of reproductive structures in a light-dependent manner, promoting sexual development in the darkness while stimulating asexual sporulation under illumination. Deletion of the N. crassa ve-1 locus by homologous gene replacement causes formation of shortened aerial hyphae accompanied by a significant increase in asexual conidiation, which is not light-dependent. Our data suggest that the conserved velvet proteins of A. nidulans and N. crassa exhibit both similar and different functions to influence development of these two ascomycetes.  相似文献   
93.
The inhibition of two human cytosolic carbonic anhydrase (hCA, EC 4.2.1.1) isozymes, hCA I and II, with a series of salicylic acid derivatives was investigated by using the esterase method with 4-nitrophenyl acetate as substrate. IC(50) values for sulfasalazine, diflunisal, 5-chlorosalicylic acid, dinitrosalicylic acid, 4-aminosalicylic acid, 4-sulfosalicylic acid, 5-sulfosalicylic acid, salicylic acid, acetylsalicylic acid (aspirin) and 3-metylsalicylic acid were of 3.04 microM, 3.38 microM, 4.07 microM, 7.64 microM, 0.13 mM, 0.29 mM, 0.42 mM, 0.56 mM, 2.71 mM and 3.07 mM for hCA I and of 4.49 microM, 2.70 microM, 0.72 microM, 2.80 microM, 0.75 mM, 0.72 mM, 0.29 mM, 0.68 mM, 1.16 mM and 4.70 mM for hCA II, respectively. Lineweaver-Burk plots were also used for the determination of the inhibition mechanism of these substituted phenols, most of which were noncompetitive inhibitors with this substrate. Some salicylic acid derivatives investigated here showed effective hCA I and II inhibitory activity, and might be used as leads for generating enzyme inhibitors eventually targeting other isoforms which have not been assayed yet for their interactions with such agents.  相似文献   
94.
We have investigated the inter-relationship between the opioid and catecholaminergic systems in the control of LH secretion, and the involvement of &mgr;- and kappa-opioid subtypes in this process. Conscious female rats were intraperitoneally injected with either &mgr;- (diamorphine) or kappa-opioid agonists (U-50488H) alone or with their respective antagonists (naloxone and MR2266) before the critical period on pro-estrus. Hypothalamic catecholamine and plasma LH levels were determined by HPLC-ECD and RIA, respectively. Both &mgr;- and kappa-agonists significantly decreased concentrations of noradrenaline and its metabolite (DHPG) in all the hypothalamic regions examined concomitant with inhibition of the LH surge. Dopamine levels were selectively reduced only by the &mgr;-agonist in the MPOA. The inhibitory effects of both opioid agonists were mostly reversed following their co-administration with naloxone and MR2266 (except the kappa-antagonist on LH). These results indicate that both the &mgr;- and kappa-opioid subtypes may be involved in the inhibition of the LH surge by altering the hypothalamic noradrenaline content.  相似文献   
95.
An investigation was made as to whether the sexual cycle and pregnancy can be determined by means of vaginal smear in chinchillas. This study represents the first attempt to record changes which occur in the pattern of exfoliated cells in chinchilla's vaginal smear during anoestrus, proestrus, oestrus, metoestrus and pregnancy. Fifteen female chinchillas aged from 8 months to 3 years and bred through harem breeding method were used. The major change during proestrus was an increase in the proportion of superficial cells, with a corresponding decrease in other cells. Goblet cells were observed in the smears prepared by strong aspiration during this cycle. Neutrophils, small and large intermediates and parabasal cells were not found in the smear during oestrus and the smear consisted of superficial cells only. In the proportion of neutrophils, small and large intermediates and parabasal cells increased during metoestrus. In addition, metoestrum and foam cells were found in this cycle. In anoestrus; superficial and parabasal cells were present in small numbers. Also small and large intermediate cells as well as neutrophils were present. Traces of foam and metoestrum cells were found. During pregnancy, neutrophils generally of medium density were present, parabasal; small and large intermediate cells were present at low or medium density, and superficial cells were only present in trace amounts.  相似文献   
96.
Studies investigated the patient‐care (in‐hospital) and outside‐the‐hospital energy consumptions for delivering the hemodialysis (HD) service. A life cycle inventory methodology was used for this patient‐based analysis for two hospitals located in Wichita, Kansas. It was found that, for both hospitals, the actual HD machines consumed approximately 3.5 kilowatt‐hours (kWh) of electrical energy per HD, only 8% to 16% of the total energy used for delivering the HD service (in hospital). This increases to 9.6 to 28.9 kWh of hospital billable energy for the whole system of HD machine, auxiliaries, and dialysis water treatment. Converting these hospital direct electrical energy values to natural resource energy (nre) then adding the cradle‐to‐gate natural resource energy for the manufacturing and supply chain of all the HD consumables, the total is 78 to 149 kWh nre/HD. The nre measures all the direct fuel burned to generate energy and is thus directly related to emissions to the air, water, and land and is a direct secondary impact on public health from HD. The ratio of outside‐the‐hospital energy to direct hospital HD electrical energy consumption is 4:1 to 7:1, so a broader base exists for improvement than just the hospital.  相似文献   
97.
The aim of this study was to determine the correlation between PM2.5 and NO2 pollutants and oxidative stress marker (8-isoprostane) and lung function tests (FVC and FEV1) in healthy children who were living and studying in three different areas of Ahvaz city including A1: Naderi site with high traffic, A2: Alavi Alley site with average traffic, and A3: Ein 2 site with low traffic (a rural area on the suburb of Ahvaz). 30 students in the 12–13 year-old range were selected from each studied zone (1, 2 and 3 sites) during three months of year. Of each student, one sample was taken every two weeks to measure 8-isoprostane of exhaled breath condensate (EBC). Air pollution data were collected from three air quality monitoring stations. Also, the relationship between air pollution and 8-isoprostane as well as lung function tests were determined using generalized estimating equations (GEE). The mean concentration of PM2.5 and NO2 in A1, A2 and A3 areas were 116, 92 and 45 (μg/m3) also 77, 53 and 14 (ppb) respectively. Among all studied students, there was a significant correlation between the increase of mean concentration of PM2.5 and NO2 in 1–4 before sampling day, increased 8-isoprostane concentration and decreased FEV1, while there was no significant correlation between them and decreased FVC. In A1 site, an increase in IQR (13 μg/m3) PM2.5 and IQR (6.5 ppb) NO2 on 1–4 days before sampling was associated with 0.38 unit (95% CI: 0.11, 0.65) and 1.1 unit (95% CI: 0.85, 1.35) increase in 8-isoprostane concentration, also decreased 121 ml and 190 ml FEV1, respectively. Results showed that the short-term exposure to traffic-related air pollution can decrease the values of lung function indices and increase the oxidative stress. It may adversely affect children’s lungs.  相似文献   
98.
We investigated the myotoxic effects of bupivacaine, ropivacaine and levobupivacaine on rat skeletal muscle and compared its apoptotic activity and acute effects on pro-nflammatory cytokines. We divided 40 Wistar albino rats into four equal groups. Rats were injected intramuscularly with 0.5% bupivacaine (group B), 0.5% ropivacaine (group R), 0.5% levobupivacaine (group L) or 0.9% normal saline (group SF). Animals were sacrificed on the second day after the injection. TNF-α, IL-1 and IL-6 levels were examined in muscle tissue using immunohistochemistry and immunofluorescence. Apoptotic cells were visualized by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. We found that levobupivacaine caused the lowest TNF-α, IL-1 and IL-6 expression levels, while the bupivacaine group caused the highest level compared to the other two agents. The greatest number of apoptotic cells was found in the bupivacaine group. Bupivacaine was more myotoxic than other anesthetic agents and increased apoptosis. The number of TUNEL positive apoptotic cells was lowest in the SF group. The greatest IL-1 immunoreactivity was found in the bupivacaine group. Bupivacaine and ropivacaine produced greater IL-6 expression than the SF group. Bupivacaine and ropivacaine caused greater TNF-α expression than the SF group, whereas the immunoreactivity of TNF-α was similar in the bupivacaine and ropivacaine groups.  相似文献   
99.
Marine traffic is a significant source of disturbance to the bottlenose dolphin population in the Istanbul Strait, Turkey. To determine the importance of this threat, behavioral data together with sighting data of both dolphins and marine vessels were assessed for 2012. The current study suggests that the Istanbul Strait is used mostly as a foraging ground for bottlenose dolphins. Nonetheless, in the same area there is intense marine traffic as well as increase of industrial fishing activities in autumn. The findings of this study indicated that high‐speed ferries and high‐speed boats were the most significant source of disturbance. Moreover, increased densities of fishing vessels resulted in a drastic decline of dolphin sightings. This study highlights that vessel type, speed, distance, and density have a cumulative negative effect on dolphins. In order to mitigate the impacts of vessels, it is necessary to establish managed areas in the Istanbul Strait. Such proposed areas should limit speed and density of marine traffic and have specific restrictions on vessel routes. We propose three different seasonal managed areas according to their values as critical habitat for bottlenose dolphins in the strait.  相似文献   
100.
The enzyme carbonic anhydrase (E.C. 4.2.1.1) has a stimulatory effect on glaucoma, an eye disease that has a risk to dogs, which are models for the human eye disease, that is similar to that in humans. In this study, some sulfonamide derivatives, 2-(3-cyclohexene-1-carbamido)-1,3,4-thiadiazole-5-sulfonamide (CCTS), 4-(3-cyclohexene-1-carbamido) methyl-benzenesulfonamide (CCBS), 2-(9-octadecenoylamido)-1,3,4-thiadiazole-5-sulfonamide (ODTS), 2-(4,7,10-trioxa-tetradecanoylamido)-1,3,4-thiadiazole-5-sulfonamide (TDTS), and 2-(8-methoxycoumarine-3-carbamido)-1,3,4-thiadiazole-5-sulfonamide (MCTS), as well as some anionic compounds (perchlorate and chloride) and existing medicines (dorzolamide-HCl, gentamicine sulphate, tropicamide, and procaine-HCl) were assayed for their inhibition of dog carbonic anhydrase (dCA), which was purified from erythrocytes on an affinity gel of L-tyrosine-sulfonamide-Sepharose 4B. ODTS showed the highest potency amongst the synthetic compounds with IC50 value 1.18 x 10(-5) M. Amongst the medicines tested, only dorzolamide showed inhibition with IC50 value 5.05 x 10(-4) M. Procaine and tropicamide actually showed an activatory effect, whereas gentamicine sulfate had no significant effect. The inhibitory effects of anionic compounds such as perchlorate and chloride were also investigated; whereas perchlorate showed inhibition, chloride did not.  相似文献   
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