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991.
Geisler J Haynes B Ekse D Dowsett M Lønning PE 《The Journal of steroid biochemistry and molecular biology》2007,104(1-2):27-34
The adipocytokine leptin has recently been shown to enhance the expression of aromatase via promoter II and I.3 using an AP-1 motif. Thus, we evaluated the correlation between plasma leptin concentrations and total body aromatization (TBA) as well as plasma levels of estrone (E(1)), estradiol (E(2)) and estrone sulfate (E(1)S) in postmenopausal breast cancer patients. Twenty-two postmenopausal women with metastatic breast cancer, participating in tracer studies for the measurement of total body aromatization (TBA) in vivo, were available. In addition, blood samples for plasma estrogens and leptin measurements were available from another 22 breast cancer patients and 114 healthy postmenopausal women participating in the mammography-screening program. Values for TBA varied from 1.46 to 4.72% while plasma leptin levels ranged from 1.83 to 95.51 ng/ml in the same group of patients. All plasma estrogen levels were in the normal range expected for postmenopausal women. We found a significant correlation between pretreatment leptin levels and TBA (r(s) 0.452, P=0.01). In contrast, basal levels of TBA did not correlate to body mass index (BMI) in the same group of patients. Plasma leptin levels correlated to plasma levels of estradiol (r(s) 0.659, P=0.007), and estrone sulfate (r(s) 0.562, P=0.01) in the group of breast cancer patients (n=44) as well as in the group of healthy postmenopausal women (estradiol, r(s) 0.363, P< or =0.001, estrone sulfate r(s) 0.353, P< or =0.001). In conclusion, we found plasma leptin levels to correlate to TBA in breast cancer patients and to plasma levels of estradiol and estrone sulfate in breast cancer patients as well as in healthy postmenopausal females. These findings suggest that leptin may influence on aromatase activity in vivo, providing a possible link between body weight and plasma estrogen levels as well as breast cancer risk. 相似文献
992.
Colmenero-Flores JM Martínez G Gamba G Vázquez N Iglesias DJ Brumós J Talón M 《The Plant journal : for cell and molecular biology》2007,50(2):278-292
Chloride (Cl(-)) is an essential nutrient and one of the most abundant inorganic anions in plant tissues. We have cloned an Arabidopsis thaliana cDNA encoding for a member of the cation-Cl(-) cotransporter (CCC) family. Deduced plant CCC proteins are highly conserved, and phylogenetic analyses revealed their relationships to the sub-family of animal K(+):Cl(-) cotransporters. In Xenopus laevis oocytes, the A. thaliana CCC protein (At CCC) catalysed the co-ordinated symport of K(+), Na(+) and Cl(-), and this transport activity was inhibited by the 'loop' diuretic bumetanide, a specific inhibitor of vertebrate Na(+):K(+):Cl(-) cotransporters, indicating that At CCC encodes for a bona fide Na(+):K(+):Cl(-) cotransporter. Analysis of At CCC promoter-beta-glucuronidase transgenic Arabidopsis plants revealed preferential expression in the root and shoot vasculature at the xylem/symplast boundary, root tips, trichomes, leaf hydathodes, leaf stipules and anthers. Plants homozygous for two independent T-DNA insertions in the CCC gene exhibited shorter organs such as inflorescence stems, roots, leaves and siliques. The elongation zone of the inflorescence stem of ccc plants often necrosed during bolt emergence, while seed production was strongly impaired. In addition, ccc plants exhibited defective Cl(-) homeostasis under high salinity, as they accumulated higher and lower Cl(-) amounts in shoots and roots, respectively, than the treated wild type, suggesting At CCC involvement in long-distance Cl(-) transport. Compelling evidence is provided on the occurrence of cation-chloride cotransporters in the plant kingdom and their significant role in major plant developmental processes and Cl(-) homeostasis. 相似文献
993.
Anaerobic co-digestion is a well established process for treating many types of organic wastes, both solid and liquid. In this study we have investigated, on a laboratory scale, the anaerobic co-digestion of olive mill wastewater (OMW) with olive mill solid waste (OMSW) using semi-continuous, feeding, tubular digesters operated at mesophilic temperatures. Each digester was fed with an influent, composed of OMW and OMSW, at an organic loading rate (OLR) varying between 0.67 and 6.67 g COD/l/d. The hydraulic retention times (HRT) were 12, 24 and 36 days. The TCOD concentrations of OMW used as the main substrate were 24, 56 and 80 g COD/l; the amount of the dry OMSW used as a co-substrate was fixed to approximately 56 g/l of OMW. The results indicated that the best methane production was about 0.95 l/l/day obtained at an OLR = 4.67 g COD/l/d, corresponding to influent TCOD = 56 g COD/l at an HRT = 12d. In contrast, the maximum TCOD removal efficiency (89%) was achieved at an OLR = 0.67 g COD/l/d, corresponding to influent TCOD = 24 g COD/l at an HRT = 36 d. Moreover, the inhibition of biogas production was observed at the highest OLR studied. 相似文献
994.
Inoculating legumes with commercial rhizobial inoculants is a common agriculture practice. Generally, inoculants are sold in liquid or in solid forms (mixed with carrier). The production of inoculants involves a step in which a high number of cells are produced, followed by the product formulation. This process is largely governed by the cost related to the medium used for rhizobial growth and by the availability of a carrier source (peat) for production of solid inoculant. Some industrial and agricultural by-products (e.g. cheese whey, malt sprouts) contain growth factors such as nitrogen and carbon, which can support growth of rhizobia. Other agro-industrial wastes (e.g. plant compost, filtermud, fly-ash) can be used as a carrier for rhizobial inoculant. More recently, wastewater sludge, a worldwide recyclable waste, has shown good potential for inoculant production as a growth medium and as a carrier (dehydrated sludge). Sludge usually contains nutrient elements at concentrations sufficient to sustain rhizobial growth and heavy metals are usually below the recommended level. In some cases, growth conditions can be optimized by a sludge pre-treatment or by the addition of nutrients. Inoculants produced in wastewater sludge are efficient for nodulation and nitrogen fixation with legumes as compared to standard inoculants. This new approach described in this review offers a safe environmental alternative for both waste treatment/disposal and inoculant production. 相似文献
995.
Novel triazole amino acids were synthesized as probes to investigate ligand-protein binding interactions of the neutral amino acid transporter SN1. The bonding hypothesis to be tested was that the side chains of endogenous substrates are acting as H-bond acceptors. Although limited inhibition of (3)H-L-glutamine uptake by SN1 expressing oocytes was observed, the synthetic compounds show a trend that suggests a hydrogen bond interaction just outside the endogenous ligand binding pocket. 相似文献
996.
Corcoran J Rodriguez F Rozas I Meana JJ Callado LF 《Bioorganic & medicinal chemistry letters》2007,17(21):6009-6012
Continuing with our search of aliphatic dicationic derivatives as I2-IBS ligands and looking at Amiloride, a known ligand of I2-IBS, we have incorporated the guanidinocarbonyl moiety into our aliphatic compounds with the intention of improving the binding to I2-IBS. Thus, we present the different approaches to the preparation and pharmacological evaluation (in human brain tissue) as I2-IBS ligands of a new series of aliphatic derivatives incorporating the guanidinocarbonyl group and with different chain length (n= 8-12, and 14 methylene groups). 相似文献
997.
López-Martínez R Hernández-Hernández F Millán-Chiu BE Manzano-Gayosso P Méndez-Tovar LJ 《Revista iberoamericana de micología》2007,24(4):283-288
We present a study on the control and elimination of the fungi affecting the mummies specifically at the museum "El Carmen", in San Angel, Mexico City. Twelve analysed mummies presented an important deterioration attributed to colonizing fungi. The degree of fungal contamination and the efficacy of imazalil were evaluated. Two samplings were performed in order to isolate and identify the fungal genera, one for control and the other after the treatment. Isolation was done by the carpet-square technique and identification was performed by morphological features. Each sampling gave a total of 100 samples as follows: 17 from the air, 23 from the walls and 60 from the mummies. Samples were cultured on Sabouraud dextrose agar. From the first sampling a total of 649 colonies corresponding to 24 genera were obtained being the most frequent Penicillium, Cladophialophora and Aspergillus. From the second sampling, after the imazalil treatment, which was applied by means of lit candles containing the antifungal drug, 57 colonies were recovered, representing a 91.2% fungal reduction; 18 genera were eliminated. In spite of resistance showed by many Penicillium strains, the imazalil is an alternative drug for the control of fungal colonization on these studied materials. 相似文献
998.
Gil-Brusola A Pemán J Santos M Salavert M Lacruz J Gobernado M 《Revista iberoamericana de micología》2007,24(4):312-316
We report a case of disseminated histoplasmosis in a 33-year old Ecuadorian patient with AIDS and a CD4 lymphocyte count of 39 cells/microl. He presented with prolonged fever and cough, was diagnosed with hemophagocytic syndrome and multiple organ failure and died 18 days after admission. Histoplasma capsulatum was isolated post-mortem from bone marrow biopsy and blood culture. In a literature review we found 22 published cases of disseminated histoplasmosis in patients with AIDS in Spain since 1988. All but two were men under 50 years old. Nineteen had been born or had lived in endemic areas. The diagnosis of histoplasmosis was established by culture of bone marrow biopsy in 10 cases. Itraconazole was introduced as a second drug after amphotericin B in ten of the thirteen patients who survived. 相似文献
999.
Gisbert JP Calvet X Feu F Bory F Cosme A Almela P Santolaria S Aznárez R Castro M Fernández N García-Grávalos R Cañete N Benages A Montoro M Borda F Pérez-Aisa A Piqué JM 《Helicobacter》2007,12(4):279-286
AIM: To evaluate the effect of Helicobacter pylori eradication on ulcer bleeding recurrence in a prospective, long-term study including more than 400 patients. METHODS: Patients with peptic ulcer bleeding were prospectively included. H. pylori infection was confirmed by rapid urease test, histology or (13)C-urea breath test. Several eradication regimens were used. Ranitidine 150 mg was administered daily until eradication was confirmed by breath test 8 weeks after completing eradication therapy. Patients with therapy failure received a second or third course of therapy. Patients with eradication success did not receive maintenance anti-ulcer therapy, and were controlled yearly with a repeated breath test. RESULTS: Four hundred and twenty-two patients were followed up for at least 12 months, with a total of 906 patient-years of follow up. Mean age was 59 years, and 35% were previous nonsteroidal anti-inflammatory drug (NSAID) users. Sixty-nine percent had duodenal, 24% gastric, and 7% pyloric ulcer. Recurrence of bleeding was demonstrated in two patients at 1 year (incidence: 0.22% per patient-year of follow up), which occurred after NSAID use in both cases. CONCLUSION: Peptic ulcer rebleeding does not occur in patients with complicated ulcers after H. pylori eradication. Maintenance anti-ulcer (antisecretory) therapy is not necessary if eradication is achieved. 相似文献
1000.