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P Conde

Publications and source records attributed to P Conde.

16 recordsLinked to original sources
PubMed2004

Limits for the central production of Theta+ and Xi(--)pentaquarks in 920-GeV pA collisions.

We have searched for Theta+(1540) and Xi(--)(1862) pentaquark candidates in proton-induced reactions on C, Ti, and W targets at midrapidity and square root of s = 41.6 GeV. In 2 x 10(8) inelastic events we find no evidence for narrow (sigma approximately 5 MeV) signals in the Theta+ --> pK0(S) and Xi(--) --> Xi- pi- channels; our 95% C.L. upper limits (UL) for the inclusive production cross section times branching fraction B dsigma/dy/(y approximately 0) are (4-16) mub/N for a Theta+ mass between 1521 and 1555 MeV, and 2.5 mub/N for the Xi(--). The UL of the yield ratio of Theta+/Lambda(1520) < (3-12)% is significantly lower than model predictions. Our UL of B Xi(--)/Xi(1530)0 < 4% is at variance with the results that have provided the first evidence for the Xi(--).

Journal Article↗
PubMed2003

Somatic embryogenesis and plant regeneration from leaves of Ulmus minor Mill.

Somatic embryogenesis from mature elm ( Ulmus minor Mill.) in vitro-cloned material is possible. Embryogenic callus was obtained from leaves inoculated on two different MS-based media-one supplemented with 2.3 microM 2,4-dichlorophenoxyacetic acid (I2) and the other supplemented with 1.1 microM kinetin (I6). However, only leaves cultured on medium I6 produced somatic embryos, at the globular stage, when embryogenic callus was maintained in induction media. When embryogenic callus from medium I6 was transferred to basal medium, somatic embryos with green cotyledons were obtained. An average of 35.9% of these embryos converted easily into normal plants in conversion medium with 1% sucrose. Acclimatisation reached 39.7%, and this was not significantly different from a control group consisting of plants propagated by axillary buds. No morphological differences were observed between plants derived from somatic embryos and control plants. Also, no differences in ploidy were detected between the somatic embryo-derived plants and the mother plants.

2,4-Dichlorophenoxyacetic Acid↗
PubMed2002

Using the Web to aid biochemists and microbiologists: an example of computer-based learning using PCR as an example.

The aim of this study was two-fold: to make available to the medical community a fast, efficient tool for troubleshooting PCR problems, and to demonstrate that hypermedia allow one to approach this kind of problem in a new, more useful way. The Web provides access to an enormous amount of information in the medical area, and in particular enables troubleshooting of new techniques in the medical laboratory. Currently it is possible to find textual information but it is not always easy to find hypermedia information. In many cases authors change only the means of dissemination of a book or paper to the Web, but do not adapt the information to the features of this new medium. The prototype of our hypermedia application was developed using Director and Flash programs (Macromedia), the application was developed from a decision tree built as a result of information compiled from expert PCR users and the existing literature. It was implemented on a website using Dreamweaver (Macromedia). The usefulness and possibilities of this application have been tested with physicians, medical laboratory technicians, and health science students, and have been proven to be more effective than traditional methods, both in education processes and in helping researchers and medical laboratory technicians in their daily work. The advance and popularization of the Internet in the medical profession requires information on the Web to adapt to the advantages offered by hypermedia. This new step must be taken, and the Web must offer medical users not only a different medium of information distribution but also a new way of handling and obtaining information.

Biochemistry↗
PubMed1998

Bilirubinate granules: main pathologic bile component in patients with idiopathic acute pancreatitis.

OBJECTIVE: The aim of this study was to evaluate the main pathologic component of bile obtained by biliary drainage in patients with acute idiopathic pancreatitis and therapeutic implications. METHOD: Eighteen patients diagnosed with idiopathic acute pancreatitis underwent biliary drainage. Microscopic evaluation of bile was performed and pathologic components were classified in cholesterol microcrystals, bilirubinate granules, and calcium microspherolites. RESULTS: Five patients showed no abnormalities. In 11 patients, bilirubinate granules were found, cholesterol microcrystals in two, and Giardia lamblia in two. CONCLUSION: Bilirubinate granules are the main pathologic component of bile in patients with acute idiopathic pancreatitis. Cholecystectomy is the preferred therapeutic approach.

Adult↗
PubMed1979

Acidic ribosomal proteins from eukaryotic cells. Effect on ribosomal functions.

Precipitation of Saccharomyces cerevisiae ribosomes by ethanol under experimental conditions that do not release the ribosomal proteins can affect the activity of the particles. In the presence of 0.4 M NH4Cl and 50% ethanol only the most acidic proteins from yeast and rat liver ribosomes are released. At 1 M NH4Cl two more non-acidic proteins are lost from the ribosomes. The release of the acidic proteins causes a small inactivation of the polymerizing activity of the particles, additional to that caused by the precipitation itself. The elongation-factor-2-dependent GTP hydrolysis of the ribosomes is, however, more affected by the loss of acidic proteins. These proteins can stimulate the GTPase but not the polymerising activity when added back to the treated particles. Eukaryotic proteins cannot be substituted for bacterial acidic proteins L7 and L12. We have not detected immunological cross-reaction between acidic proteins from Escherichia coli and those from yeast, Artemia salina and rat liver or between acidic proteins from these eukaryotic ribosomes among themselves.

GTP Phosphohydrolase-Linked Elongation Factors↗
PubMed1979

Peptidyl transferase of bacterial ribosome: resistance to proteinase K.

70-S ribosomes and 50-S ribosomal subunits from Escherichia coli D10 were treated with proteinase K for increasing periods of time. Peptidyl transferase activity and sparsomycin-induced binding of (U)C-A-C-C-A-[3H]Leu-Ac were tested in the treated particles, the binding of the substrate being more sensitive to the protease than peptide bond formation. Comparison of the amounts of proteins present in the treated particles with the residual activity indicates that only proteins L3 and L14 are released at a similar rate to that at which peptidyl transferase activity is lost. Proteins related to this ribosomal activity by other techniques are lost at a faster rate than the activity itself. In addition, the results indicate that sparsomycin stimulates the binding of the substrate by a different mechanism from that which inhibits peptide bond formation.

Acyltransferases↗
PubMedDate not supplied

Hydrogastric sonography in the preoperative staging of gastric cancer.

PURPOSE: Depth of wall invasion is the main prognostic factor in gastric cancer. We studied the utility of hydrogastric sonography in the evaluation of transmural infiltration by gastric cancer. METHODS: Thirty-seven patients with gastric adenocarcinoma were examined before surgery with a 5-MHz probe after the ingestion of 100-400 ml of water (mean, 330 ml). Sonographic results were compared with pathologic classifications obtained after surgery. RESULTS: Of the 37 tumors, 15 were found at surgery to be in the antrum, 10 were in the gastric body, 5 were proximal, and 7 were diffuse. After surgery, tumors were classified as follows: 2 (5%) T1, 4 (11%) T2, 15 (41%) T3, and 16 (43%) T4. Hydrogastric sonography correctly classified 30 (81%) of the 37 tumors. Sonography was correct for 2 (100%) of the 2 T1 tumors, 2 (50%) of the 4 T2 tumors, 13 (87%) of the 15 T3 tumors, and 13 (81%) of the 16 T4 tumors. Five sonographic errors were due to understaging and 4 to overstaging. With regard to tumor site, sonographic results were correct for 4 (57%) of the 7 diffuse tumors, 3 (60%) of the 5 proximal tumors, 9 (90%) of the 10 gastric body tumors, and 14 (93%) of the 15 antral tumors. CONCLUSIONS: Hydrogastric sonography is useful for preoperative evaluation of transmural infiltration by gastric cancers, particularly tumors in the antrum or gastric body.

Adenocarcinoma↗
PubMedDate not supplied

[Usefulness of abdominal echography in the diagnosis of active Crohn's disease].

OBJECTIVE: The aim of this study was to evaluate the relevance of the ultrasonography in assessing activity in a series of patients with Crohn's disease. PATIENTS AND METHODS: A series of 24 patients with active (Crohn's disease activity index > 150) ileal or ileocolonic Crohn disease underwent abdominal ultrasonography. RESULTS: There was a significant correlation between bowel wall thickening and the Crohn's disease activity index: the higher the bowel wall thickening was the higher were the values of Crohn's disease activity index. Two or more ultrasound studies were performed in 10 patients with bowel wall > 4 mm during treatment, and a progressive normalization of bowel wall size was observed with new thickening when recurrence occurred. CONCLUSIONS: A bowel wall thickening (> or = 4 mm) was found in patients with active Crohn's disease. A patient with bowel wall thickness > 6 mm should make us suspect the presence of stenosis. Abdominal ultrasonography is an accurate method in the first assessment of Crohn's disease because its high correlation with the Crohn's disease activity index.

Abdomen↗