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101.
The effect of submaximal endurance training (SET) on sympathoadrenal activity is not clear. We tested the hypothesis that SET (90 min/day, 5 days/wk, for 12 wk) elevates mRNA expression of catecholamine (CA) biosynthetic enzymes, tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DbetaH) in the adrenal medullae of adult, female Sprague-Dawley rats. SET increased TH protein level by 35%, TH activity by 62%, TH mRNA expression by 40%, and DbetaH mRNA expression by 67%. In addition, we examined the effect of SET on Fos-related antigens (FRAs), FRA-2 immunoreactivity, and activator protein (AP)-1 binding activity. SET increased AP-1 binding activity by 78%; however, it did not affect late FRAs and FRA-2 immunoreactivity. Because the regulation of neuropeptide Y (NPY) often parallels that of CAs, we also examined the effect of SET on NPY mRNA expression. Indeed, SET elevated NPY mRNA expression as well. We conclude that 1) SET elicits a pretranslational stimulatory effect on adrenomedullary CA biosynthetic enzymes, 2) another immediate early mRNA product, rather than FRA-2, may contribute to the increase in AP-1 binding activity in response to SET, and 3) SET increases NPY mRNA expression.  相似文献   
102.
People employed in the shoe manufacture and repair industry are at an increased risk for cancer, the strongest evidence being for nasal cancer and leukaemia. A possible causal role for formaldehyde is likely for cancer of the buccal cavity and nasopharynx. Exfoliated buccal cells are good source of tissue for monitoring human exposure to inhaled and ingested occupational and environmental genotoxicants. To assess the cytogenetic damage related to occupational exposure to airborne chemicals during shoe-making and the processes in pathology and anatomy laboratories, the micronuclei (MN) count per 3000 cells was measured in buccal smears from shoe-workers (group I, n = 22) exposed to mainly n-hexane, toluene and methyl ethyl ketone (MEK) and from anatomy and pathology staff (group II, n = 28) exposed to formaldehyde (FA). Eighteen male university staff were used as controls. The mean time-weighted average (TWA) concentrations of n-hexane, toluene and MEK in 10 small shoe workshops were 58.07 p.p.m., 26.62 p.p.m. and 11.39 p.p.m., respectively. The measured air concentrations of FA in the breathing zone of the anatomy and pathology laboratory workers were between 2 and 4 p.p.m. Levels of 2,5-hexadione (2,5-HD) and hippuric acid (HA), metabolic markers of n-hexane and toluene exposure, respectively, were significantly higher in the urine of workers in group I than in control subjects (p < 0.001 and p < 0.01, respectively). The mean (+/- SD) MN (0/00) [corrected] frequencies in buccal mucosa cells from workers in group I, group II and controls were 0.62 +/- 0.45%, 0.71 +/- 0.56% and 0.33 +/- 0.30%, respectively (p < 0.05 and p < 0.05 compared with controls for group I and group II, respectively). The effects of smoking, age and duration of exposure on the frequency of micronucleated buccal cells from workers in all three groups studied were also evaluated. Overall, the results suggest that occupational exposure to organic solvents, mainly n-hexane, toluene, MEK and FA, may cause cytogenetic damage in buccal cells and that use of exfoliated buccal cells seems to be appropriate to measure exposure to organic solvents.  相似文献   
103.
M. Beklioglu  O. Ince  I. Tuzun 《Hydrobiologia》2003,490(1-3):93-105
Nutrient loading in lakes is recognized as a serious threat to water quality. Over 25 years of raw sewage effluent discharge shifted Lake Eymir from a state dominated by submerged plants to a turbid water state. Successful effluent diversion undertaken in 1995 achieved 88% and 95% reductions in the areal loading of total phosphorus (TP) and dissolved inorganic nitrogen (DIN), respectively. Furthermore, the reduced load of TP was very close to the suggested threshold areal load (0.6 g m–2 yr–1) to attain recovery. Even though diversion also reduced the in-lake TP level by half, the poor water clarity and low submerged plant coverage (112 ± 43 cm and 2.5% coverage of the lake total surface area, respectively) persisted. Domination of the fish stock by planktivorous tench (Tinca tinca L.) and the benthivorous common carp (Cyprinus carpio L.) (66 ± 0.7 and 31 ± 1 kg CPUE, respectively) appeared to perpetuate the poor water condition. A substantial fish removal effort over 1 year achieved a 57% reduction in the fish stock which led to a 2.5-fold increase in Secchi disk transparency. This increase occurred largely because of a 4.5-fold decrease in the inorganic suspended solid concentration, and to some extent, a decrease in chlorophyll-a concentration. A strong top-down effect of fish on the large-sized grazers was evident as density and the body size of Daphnia pulexde Geer increased significantly after the fish removal. Even though the spring and annual euphotic depths occurred well above the maximum and mean depths of the lake, respectively, re-development of submerged plants was poor (6.2% coverage). A weak re-establishment of submerged plants might be attributed to an insufficiently viable seed bank, inappropriate chemical conditions of the sediment (severe oxygen deficiency), or to the high coot (Fulica atra L.) density. However, the top-down effect of fish appeared to be of great importance in determining water clarity, and in turn, conditions for submerged plant development in a warm temperate lake as recorded in the north temperate lakes. Furthermore, this study provides evidence for the importance of top-down control of fish, which, in turn, can be effectively utilised as a restoration strategy in warm-temperate lakes as well. More applications, along with long monitoring programs, are needed to develop a better understanding about requirements for biomanipulation success in this climate.  相似文献   
104.
The stimulation exerted by the endophytic bacterium Bacillus pumilus strain SE34 in plant defense reactions was investigated at the ultrastructural level using an in vitro system in which root-inducing T-DNA pea (Pisum sativum L.) roots were infected with the pea root-rotting fungus Fusarium oxysporum f. sp. pisi. In nonbacterized roots, the pathogen multiplied abundantly through much of the tissue including the vascular stele, whereas in prebacterized roots, pathogen growth was restricted to the epidermis and the outer cortex In these prebacterized roots, typical host reactions included strengthening the epidermal and cortical cell walls and deposition of newly formed barriers beyond the infection sites. Wall appositions were found to contain large amounts of callose in addition to being infiltrated with phenolic compounds. The labeling pattern obtained with the gold-complexed laccase showed that phenolics were widely distributed in Fusarium-challenged, bacterized roots. Such compounds accumulated in the host cell walls and the intercellular spaces as well as at the surface or even inside of the invading hyphae of the pathogen. The wall-bound chitin component in Fusarium hyphae colonizing bacterized roots was preserved even when hyphae had undergone substantial degradation. These observations confirm that endophytic bacteria may function as potential inducers of plant disease resistance.  相似文献   
105.
Experimental autoimmune myasthenia gravis (EAMG) is severe in RIIIS/J mice, despite a significant B cell immunodeficiency and a massive TCR V beta gene deletion. Severity of EAMG in RIIIS/J mice is greater than MHC-identical (H-2(r)) B10.RIII mice, suggesting the influence of non-MHC genes as an EAMG-potentiating factor in this strain. To delineate the role of deleted TCR V beta genes in RIIIS/J mice, we obtained (RIIIS/J x B10.RIII)F(1) (V beta(b/c)) x RIIIS/J (V beta(c)) backcross mice using Mendelian genetic methods and immunized them with acetylcholine receptor. EAMG susceptibility was not elevated in mice with V beta(c) genotype having 70% V beta gene deletion. Next, we performed microarray analysis on 12,488 spleen cDNAs obtained from spleens of naive RIIIS/J and B10.RIII mice. In RIIIS/J mice, 263 cDNAs were overexpressed and 303 cDNAs were underexpressed greater than 2-fold, compared with B10.RIII mice. TCR gene expression was augmented, whereas NK receptor, C1q, and C3 gene expressions were diminished in RIIIS/J mice. RIIIS/J mice also had increased lymph node T cell counts, elevated serum anti-AChR Ab levels, and serum C3 and C1q-conjugated circulating immune complex levels. A direct correlation between increased serum C1q-conjugated circulating immune complex levels and disease severity was observed in RIIIS/J mice.  相似文献   
106.
Traditional medicine in the middle and west Black Sea regions: Amasya, Bilecik, Bolu, Çankin, Samsun, Sinop and Tokat provinces has been studied and 194 remedies obtained from 96 plant and 5 animal species are compiled. Vernacular names, parts used, methods of preparation, and medicinal usages are listed.  相似文献   
107.
The impact of additive manufacturing in our lives has been increasing constantly. One of the frontiers in this change is the medical devices. 3D printing technologies not only enable the personalization of implantable devices with respect to patient-specific anatomy, pathology and biomechanical properties but they also provide new opportunities in related areas such as surgical education, minimally invasive diagnosis, medical research and disease models. In this review, we cover the recent clinical applications of 3D printing with a particular focus on implantable devices. The current technical bottlenecks in 3D printing in view of the needs in clinical applications are explained and recent advances to overcome these challenges are presented. 3D printing with cells (bioprinting); an exciting subfield of 3D printing, is covered in the context of tissue engineering and regenerative medicine and current developments in bioinks are discussed. Also emerging applications of bioprinting beyond health, such as biorobotics and soft robotics, are introduced. As the technical challenges related to printing rate, precision and cost are steadily being solved, it can be envisioned that 3D printers will become common on-site instruments in medical practice with the possibility of custom-made, on-demand implants and, eventually, tissue engineered organs with active parts developed with biorobotics techniques.  相似文献   
108.
Modern plant breeding heavily relies on the use of molecular markers. In recent years, next generation sequencing (NGS) emerged as a powerful technology to discover DNA sequence polymorphisms and generate molecular markers very rapidly and cost effectively, accelerating the plant breeding programmes. A single dominant locus, Frl, in tomato provides resistance to the fungal pathogen Fusarium oxysporum f. sp. radicis-lycopersici (FORL), causative agent of Fusarium crown and root rot. In this study, we describe the generation of molecular markers associated with the Frl locus. An F2 mapping population between an FORL resistant and a susceptible cultivar was generated. NGS technology was then used to sequence the genomes of a susceptible and a resistant parent as well the genomes of bulked resistant and susceptible F2 lines. We zoomed into the Frl locus and mapped the locus to a 900 kb interval on chromosome 9. Polymorphic single-nucleotide polymorphisms (SNPs) within the interval were identified and markers co-segregating with the resistant phenotype were generated. Some of these markers were tested successfully with commercial tomato varieties indicating that they can be used for marker-assisted selection in large-scale breeding programmes.  相似文献   
109.
Owing to a lack of appropriate diagnostic and therapeutic approaches for mycotic keratitis, approximately one million cases of preventable corneal blindness are reported each year. The number of keratitis cases due to infection with Fusarium is increasing significantly worldwide, many of which are not treated adequately and in a timely manner due to frequent misdiagnosis. In the current report, we describe three cases of keratitis caused by Fusarium solani sensu stricto (FSSC5) from Turkey and The Netherlands, following ocular trauma. The etiological agent of keratitis, FSSC5, identified by sequencing of the partial tef1-α gene, exhibited low minimum inhibitory concentrations (MICs) of 1 µg/mL for amphotericin B and high MICs above the published epidemiological cutoff values for voriconazole (8 µg/mL). Patients were successfully treated with topical amphotericin B and voriconazole with complete recovery.  相似文献   
110.
Pyruvate kinase isoenzyme M2 (PKM2) is one of the most important control point enzyme in glycolysis pathway. Hence, its inhibitors and activators are currently considered as the potential anticancer agents. The effect of 28 polyphenolic compounds on the enzyme activity was investigated in vitro. Among these compounds, neoeriocitrin, (?)-catechin gallate, fisetin, (±)-taxifolin and (?)-epicatechin have the highest inhibition effect with IC50 value within 0.65–1.33?µM range. Myricetin and quercetin 3-β-d-glucoside exhibited the highest activation effect with 0.51 and 1.34?µM AC50 values, respectively. Twelve of the compounds showed inhibition effect within 7–38?µM range of IC50 value. Sinapinic acid and p-coumaric acid showed an activation effect with 26.2 and 22.2?µM AC50 values, respectively. The results propose that the polyphenolics may be the potential PKM2 inhibitors/activators, and they may be used as lead compounds for the synthesis of new inhibitors or activators of this enzyme.  相似文献   
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