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C Aquino

Publications and source records attributed to C Aquino.

13 recordsLinked to original sources
PubMed2003

Molecular diversity and multilocus organization of the parental lines used in the International Rice Molecular Breeding Program.

One hundred and ninety three parental lines obtained from 26 countries for an international rice molecular breeding program were evaluated using 101 well-distributed simple sequence repeat (SSR) markers. An overall genetic diversity of 0.68 and an average of 6.3 alleles per locus were revealed, indicating a high level of genetic variation in these lines. Cluster analysis of the 193 accessions showed three major groups and nine subgroups. Group I corresponded to the classical indica subspecies, whereas groups II and III belong to the japonica subspecies. Indica and japonica differentiation accounted for only 6.5% of the total variation in the entire sample and 93.5% was due to within-subspecies diversity. Differentiation among eco-geographic regions accounted for 24% of the diversity within the subspecies. Larger amounts of the eco-geographical differentiation were resolved within japonica than within indica. The largest indica-japonica differentiation based on the single locus level was detected by markers on chromosomes 9 and 12, while the smallest differentiation was detected by markers on chromosomes 4 and 8. Furthermore, genetic differences at the single-locus and two-locus levels, as well as components due to allelic and gametic differentiation, were revealed between indica and japonica and among the main geographic regions. The multilocus analysis in genetic diversity showed a higher proportion of variation caused by predominant non-random associations of different loci within and among the classified subspecies and geographic subdivisions. The results suggest that selection for eco-geographical adaptation on multilocus associations was largely responsible for the maintenance of the extensive variation in the primary gene pool of rice.

Alleles↗
PubMed1996

Discovery of 1,5-benzodiazepines with peripheral cholecystokinin (CCK-A) receptor agonist activity (II): Optimization of the C3 amino substituent.

Analogs of the previously reported 1,5-benzodiazepine peripheral cholecystokinin (CCK-A) receptor agonist 1 were prepared which explore substitution and/or replacement of the C-3 phenyl urea moiety. Agonist efficacy on the isolated guinea pig gallbladder (GPGB) was retained with a variety of substituted ureas and amide analogs. Three compounds were identified which were orally active in the mouse gallbladder emptying assay (MGBE). The 2-indolamide (52) and N-(carboxymethyl)-2-indolamide (54) derivatives had improved affinity for the human CCK-A receptor but reduced agonist efficacy on the GPGB. Neither indolamide was orally active in a rat feeding assay. In contrast, the (3-carboxyphenyl)urea derivative (29, GW7854) had moderately increased affinity for the human CCK-B receptor but was a potent full agonist on the GPGB and was orally active in both the MGBE and rat feeding assays. GW7854 was a full agonist (EC50 = 60 nM) for calcium mobilization on CHO K1 cells expressing hCCK-A receptors and a potent antagonist of CCK-8 (pA2 = 9.1) on CHO K1 cells expressing hCCK-B receptors. GW7854 is a potent mixed CCK-A agonist/CCK-B antagonist which is orally active in two in vivo models of CCK-A-mediated agonist activity.

Animals↗
PubMed1988

Natural infections of phlebotomine sandflies with Trypanosomatidae in central and south Italy.

In a survey of Leishmania infections of phlebotomine sandflies caught in central and south Italy in 1986, zymodeme MON-1 (Montpellier 1) of Leishmania infantum was isolated from Phlebotomus perniciosus and L. tarentolae [= Trypanosoma platydactyli?] was isolated from Sergentomyia minuta, providing for mainland Italy the first direct proof of these long-suspected parasite-vector associations. The roles of P. perfiliewi and P. perniciosus in the transmission of Leishmania spp. in Italy are discussed.

Animals↗
PubMed1976

Transplantation of the pancreas.

A procedure was developed in the laboratory for pancreatic allotransplantation in pancreatectomized dogs. Dogs with such grafts have survived for many months when treated with azathioprene and prednisone to prevent rejection. Contrary to usual beliefs, the pancreas is not unduly sensitive to total ischemia since it has been possible to successfully preserve a canine pancreas in vitro with hypothermia for periods up to 24 hours. Such preserved pancreas' have then been allotransplanted into pancreatectomized dogs with survival of the dogs for long periods. We have now done pancreaticoduodenal allotransplantation in 13 patients with juvenile onset diabetes mellitus. Nine of these patients also had renal failure and received simultaneously a renal allograft taken from the same cadaver. In all but one of these patients the pancreas functioned immediately. Two patients with juvenile onset diabetes mellitus and severe retinopathy but without terminal renal failure have received pancreaticoduodenal allografts alone. In both of these patients the pancreas functioned immediately but problems with the duodenum necessitated the removal of the pancreaticoduodenal allograft which did not show signs of rejection. As a result of the findings of increased sensitivity of the kidney and duodenum to rejection we have now modified our technique to transplant the pancreas alone. This technique was used in one patient with juvenile onset diabetes mellitus and severe retinopathy. Her renal function was only moderately reduced. The pancreatic allograft initially functioned normally but then was removed at 28 days because of clinical signs of rejection of the pancreas which were confirmed by the microscopic findings. Despite the promise of islet-cell transplantation, no long term functioning allografts have resulted in animals or man. Thus we need to continue with whole organ pancreatic allografts by various techniques if diabetes mellitus is to be controlled.

Adult↗