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1.
Maturity Onset Diabetes of the Young (MODY) is a heterogeneous group of genetic diseases characterized by a primary defect in insulin secretion and hyperglycemia, non-ketotic disease, monogenic autosomal dominant mode of inheritance, age at onset less than 25 years, and lack of auto-antibodies. It accounts for 2–5% of all cases of non-type 1 diabetes. MODY subtype 2 is caused by mutations in the glucokinase (GCK) gene. In this study, we sequenced the GCK gene of two volunteers with clinical diagnosis for MODY2 and we were able to identify four mutations including one for a premature stop codon (c.76C>T). Based on these results, we have developed a specific PCR-RFLP assay to detect this mutation and tested 122 related volunteers from the same family. This mutation in the GCK gene was detected in 21 additional subjects who also had the clinical features of this genetic disease. In conclusion, we identified new GCK gene mutations in a Brazilian family of Italian descendance, with one due to a premature stop codon located in the second exon of the gene. We also developed a specific assay that is fast, cheap and reliable to detect this mutation. Finally, we built a molecular ancestry model based on our results for the migration of individuals carrying this genetic mutation from Northern Italy to Brazil. 相似文献
2.
In the River Lobos-Ucero and its tributary the River Avión-Milanos (Duero basin, Old Castile, Central Spain), two limestone streams fed by aquifers, the population of brown trout, as compared with the populations of other European streams, shows a high growth rate, high condition coefficients, short life-span and early age at first maturity. Gonad cycle was also studied. Size distributions of unshed eggs exhibit a dynamic activity with a bi-modal distribution from June onwards, spawning occurred in the last days of November. Fecundity (F) can be predicted from trout length (L, mm) according to the equation: F= –646.47+5.6167 · L. Numbers and standing crop of trout range from 18 to 3903 ind. ha–1 and 3.6 to 452.9 Kg ha–1, reaching higher values in the sites close to the aquifers. Egg production had values of 22.4 and 18.0 eggs m–2 in the Rivers Ucero and Avión-Milanos respectively. Some factors suggested as regulators of these demographical characteristics are discussed in the light of recent literature. 相似文献
3.
Natural antibodies to interferon-gamma 总被引:3,自引:0,他引:3
Natural antibodies to interferon (IFN)-γ were detected in the serum of virus-infected patients and also, at a low titre, in
the serum of healthy subjects. The increased titre of antibodies to IFN-γ in the sera of virus-infected patients, and its
decrease with clinical resolution, indicate that these antibodies are related to viral infection and probably reflect IFN-γ
production as a result of antigenic stimulationin vivo. Natural antibodies to IFN-γ were affinity purified and studied for their capability to interferein vitro with the multiple activities of the lymphokine. Data obtained show that these human anti-IFN-γ antibodies have no inhibitory
effect on the antiviral and antiproliferative activity of IFN-γ and do not interfere with the binding of the lymphokine to
its specific cell receptor. Instead, they can inhibit the expression of HLA-DR antigens induced by IFN-γ on U937 cells and
interfere, in mixed lymphocyte culture, with the proliferation of lymphocytes and the generation of cytotoxic lymphocytes.
Experiments in animal models suggest that natural antibodies to IFN-γ may have a role in the immunoregulatory process limiting
the intensity and/or duration of immune response. As they can interfere only with the immunomodulating activities of IFN-γ,
these antibodies might open up new therapeutic approaches to diseases with evidence of activated cell-mediated immunity. 相似文献
4.
J Ignacio Andrés Jesús Alcázar José M Alonso Adolfo Díaz Javier Fernández Pilar Gil Laura Iturrino Encarna Matesanz Theo F Meert Anton Megens Victor K Sipido 《Bioorganic & medicinal chemistry letters》2002,12(2):249-253
Following the programme started at Janssen Research Foundation searching for 5-HT(2A/2C) antagonists, we now report on the synthesis of a series of substituted 2-(Dimethylaminomethyl)-2,3,3a,8-tetrahydrodibenzo[c,f]isoxazolo[2,3-a]azepine derivatives. The 5-HT(2A), 5-HT(2C) and H(1) receptor affinities as well as the mCPP antagonistic activity of the compounds synthesised is described. 相似文献
5.
S.M. Teresa Hernndez-Sotomayor Marina Macías-Silva Magdalena PlebanÜski J. Adolfo García-Sinz 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1988,972(3)
In hepatocytes obtained from hypothyroid rats, phorbol myristate acetate (PMA) and vasopressin diminished the accumulation of cyclic AMP and the stimulation of ureagenesis induced by isoprenaline or glucagon without altering significantly the accumulation of cyclic AMP induced by forskolin. Pretreatment with PMA markedly reduced the stimulation of ureagenesis and the accumulation of cyclic AMP induced by isoprenaline or glucagon. In membranes from cells pretreated with PMA, the stimulation of adenylate cyclase induced by isoprenaline + GTP, glucagon + GTP or by Gpp[NH]p were clearly diminished as compared to the control, whereas forskolin-stimulated activity was not affected. The data indicate heterologous desensitization of adenylate cyclase. It was also observed that the homologous (García-Sáinz J.A. and Michel, B. (1987) Biochem. J. 246, 331–336) and this heterologous β-adrenergic desensitizations were additive. Pertussis toxin treatment markedly reduced the heterologous desensitization of adenylate cyclase but not the homologous β-adrenergic desensitization. It is concluded that the homologous and heterologous desensitizations involve different mechanisms. The homologous desensitization seems to occur at the receptor level, whereas the heterologous probably involves the guanine nucleotide-binding regulatory protein, Ns. 相似文献
6.
Giuseppe Ravizzola Gabriele Pinsi Marina Cesana Carmela De Rango Laura Peroni Prof. Adolfo Turano 《Current microbiology》1992,24(6):349-353
The protective effects of rufloxacin againstStaphylococcus aureus-induced infections were compared with those of ciprofloxacin in the granuloma pouch model in the rat. Two strains with different in vitro sensitivity to the drugs were studied. Rufloxacin concentrations persisted longer than ciprofloxacin in the exudate in the pouch cavity and were about eight times higher. Equal doses of rufloxacin and ciprofloxacin had similar antibacterial activities. However, rufloxacin inhibitedStaphylococcus aureus bacterial growth significantly longer than did ciprofloxacin. 相似文献
7.
Jerome Harold Kay Harold K. Tsuji John V. Redington Yasunaru Kawashima Yuzuru Kagawa Takashi Yamada Peter Caponegro Adolfo Mendez 《The Western journal of medicine》1967,106(3):165-169
A disc valve of new design was used successfully for the replacement of the mitral valve in patients with rheumatic mitral valve disease. This valve would appear to have the following advantages over the mitral ball valve prosthesis:• Lower left atrial pressure after replacement.• Elimination of the hazard of left ventricular outflow tract obstruction with mitral valve replacement.• Decreased incidence of thromboembolization.• Abolition of possibility of ventricular septal irritation.Despite the better outlook for this valve compared with the ball valve for mitral valve substitution, the mitral valve should always be repaired whenever feasible. Repair is possible in the majority of patients. 相似文献
8.
9.
Luigi R. Ceci Adolfo Saiardi Luisa Siculella Carla Quagliariello 《Plant molecular biology》1993,23(4):727-736
A tRNAVal (GAC) gene is located in opposite orientation 552 nucleotides (nt) down-stream of the cytochrome oxidase subunit III (coxIII) gene in sunflower mitochondria. The comparison with the homologous chloroplast DNA revealed that the tRNAVal gene is part of a 417 nucleotides DNA insertion of chloroplast origin in the mitochondrial genome. No tRNAVal is encoded in monocot mitochondrial DNA (mtDNA), whereas two tRNAVal species are coded for by potato mtDNA. The mitochondrial genomes of different plant species thus seem to encode unique sets of tRNAs and must thus be competent in importing the missing differing sets of tRNAs. 相似文献
10.
Aparicio Enric Rocaspana Rafel Palau-Ibars Antoni de Sostoa Adolfo Alcaraz Carles 《Ichthyological Research》2023,70(1):101-109
Ichthyological Research - The Mediterranean brown trout (Salmo trutta complex) is native to basins draining to the Western Mediterranean Sea, and natural populations are currently declining in... 相似文献