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C Conesa

Publications and source records attributed to C Conesa.

At least 37 records · Page 2Linked to original sources
PubMed2005

Attitude toward xenotransplantation among residents.

INTRODUCTION: The deficit in transplant organs has made it necessary to search for alternatives, among them research into xenotransplantation. However, the use of animal organs may cause rejection in society and among health professionals. The objective was to analyze the acceptance of this therapy among Residents, given that they would be the professionals most involved in its application if such a therapy proves to be useful. MATERIALS AND METHODS: A random sample stratified by the services of the Residents in a third-level hospital with an organ transplant program and accredited for teaching at undergraduate and postgraduate levels (n = 171). The attitude toward xenotransplantation was evaluated using a questionnaire that analyzes different pychosocial variables that may influence such attitude.(5) RESULTS: The sample consisted of 171 residents (mean age 28 +/- 4 years; 56% women). Attitudes toward xenotransplantation, whether the results were similar to those obtained with human organs, were positive in 81% (n = 138) of cases, with 16% (n = 27) having doubts and 3% (n = 6) being against. The attitude was more favorable among residents in favor of cadaveric donation (83% vs 57%; P < .05) and of living donation either of the kidney (90% vs 55%; P < .001) or of the liver (88% vs 56%; P < .001), and among those who consider that they might need a transplant at a given point in the future (88% vs 73%; P < .05). CONCLUSION: Residents have a positive attitude toward the application of a possible xenotransplantation in safe conditions similar to those that currently exist in human organ donation. Such a favorable attitude was greatly influenced by a positive attitude toward human organ donation, in cadaveric as well as in living donation, and when considering oneself to be a possible candidate for a transplant.

Adult↗
PubMed2005

Acceptance level of living liver donation among primary care nursing personnel.

INTRODUCTION: Living liver donation is not exempt from risks to the donor, although it is currently ethically accepted. It is important to examine the level of acceptance among the different health levels toward this therapeutic option, in order to design promotion and awareness-raising activities. The objective herein was to analyze the attitudes and the factors that condition them among nursing personnel in Primary Care (PC) toward living liver donation. MATERIALS AND METHODS: This random survey was stratified by geographical location (6 health areas in our community) among PC nurses, obtaining a total of 139 nurses from 34 health centers. Attitudes toward living liver donation were evaluated using a questionnaire on donation which included different psychosocial variables. For the distribution of the questionnaire, the nursing coordinator of each centers was contacted to distribute questionnaires which were completed anonymously. The chi-square test and Student t test were applied. RESULTS: Attitudes toward living liver donation were favorable in 89% of those questioned (n = 124) if it is related donation; 3% (n = 4) were against donating a living hemiliver and 8% (n = 11) had doubts. It is important that up to 76% (n = 106) have cared for transplant patients or patients awaiting transplant, however, no relationship was observed with attitude to this type of donation (P = .489). Of all the analyzed variables, there was only a significant relationship between attitudes and concern about possible body mutilation (P < .0005), and partners attitudes toward this matter (P < .0005). It is noteworthy that no relationship was found with attitudes toward cadaveric donation (P = .062). CONCLUSION: Despite the risk of morbidity and mortality in the donor, the attitude of the PC nursing personnel toward living liver donation was favorable, especially if the donation is related.

Adult↗
PubMed2005

Attitudes toward living liver donation among hospital personnel in services not related to transplantation.

INTRODUCTION: The deficiency in livers and waiting list mortality have encouraged more living liver donation, although it is not exempt from morbidity and mortality. The enthusiasm of transplant teams for this kind of donation is increasing; however, the attitudes toward it are not so clear among other health professionals. Our objective was to analyze the attitudes toward living liver donation among hospital professionals in services without habitual relations with transplantation. MATERIALS AND METHODS: A random sample was stratified for service not related to transplantation and job category, in a third level hospital with a transplant program. Attitudes toward living liver donation were evaluated using a psychosocial questionnaire on living donation. RESULTS: A total of 419 respondents were analyzed (doctors, n = 184; nurses, n = 119; assistant nurses, n = 80; and non-health workers, n = 36), with a mean age of 37 +/- 10 years. The attitude toward living liver donation was favorable in 82% (n = 344). Among the other respondents, half (9%; n = 38) were against and the other half (9%; n = 37) were undecided. No significant differences were found among the doctors, nurses, assistants, and non-health workers. However, when the three categories were grouped in opposition to the non-health workers, there was greater indecision among non-health workers than the others (19% vs 8%; P = .0001). On analyzing the variables that determine this attitude we observed the following: having commented upon and previously discussed donation (P = .016); believing in the possibility of needing an organ oneself (P = .0001); and being in favor of living kidney donation (P = .0001) and cadaveric donation (P = .004). CONCLUSIONS: Hospital personnel in services not related to transplantation favor living liver donation, especially if it is a related donation, despite its greater risk, except among non-health workers. However, it is important to conduct informative and awareness-raising campaigns in hospitals if such a type of transplantation is to be encouraged.

Adult↗
PubMed2005

Pathology findings in a model of auxiliary liver transplantation with portal vein arterialization in pigs.

OBJECTIVE: To determine the histological findings and temporal evolution that occur in auxiliary liver grafts as a consequence of arterialization of the portal vein (PVA). MATERIALS AND METHODS: We evaluated 10 auxiliary heterotopic liver transplants with arterialization of the PVA. The histological study was performed using an optical microscope to process liver samples with staining using hematoxylin and eosin. A biopsy of native liver tissue was used as a control. RESULTS: Two animals were excluded from the study, one due to ischemic necrosis of the graft and one that died 4 hours after transplant. All of the remaining eight animals underwent a histological study at 1 day, 7 days, and 14 days. The most significant histological findings were: (1) dilation of portal areas and sinusoids, which were detected at 24 hours and persisted; (2) thickening of the interlobular septum, which was observed after day 7 and progressively increased to day 14; (3) bile duct hyperplasia detected at the seventh day. CONCLUSIONS: The consistent, early findings in a pig liver with PVA included vascular dilation of the portal area and the sinusoids, with bile duct hyperplasia extending progressively and the thickening of interlobular connective tissue septa with a generalized perilobular connective tissue reaction, which did not seem to alter the internal structure of the lobule, which showed histologically normal hepatocytes. The fibrous reaction may be the first stage in chronic hepatopathy. Further long-term studies are required in this model.

Animals↗
PubMed2005

Attitudes toward xenotransplantation among nonhealth service workers in a hospital with a preclinical xenotransplantation program.

INTRODUCTION: Our hypothesis was that nonhealth workers (NHW) in our hospital should have a more favorable opinion toward xenotransplantation than the general population, given that this group is in closer contact with a preclinical xenotransplantation program. Therefore, our objective was to determine the attitude of NHW in a hospital with a preclinical liver xenotransplantation program and to determine the factors that influenced this attitude. MATERIALS AND METHODS: A random sample of 276 subjects in nonhealth services was used. For the distribution of the questionnaire, we contacted the head of each of the services and explained the project. They became responsible for the distribution and collection of the questionnaires in randomly selected work shifts. A random sample of 250 individuals from our community was used as a control group. RESULTS: As for animal organ donation for humans, if the results could be superimposed on those achieved by human donors, 63% would be in favor, 30% undecided, and the remaining 7% against. The attitude toward xenotransplantation was more favorable in the control group (74% versus 63%, P < .05). On analyzing the variables that influence attitudes toward xenotransplantation, we found that there is no significant relationship to the classical psychosocial variables (P > .05). However, there is a relationship to prior attitudes toward different types of human organ donation and the possibility of needing a transplant oneself. CONCLUSIONS: The attitudes toward xenotransplantation among NHW are not as favorable as in the general population.

Adult↗
PubMed2005

[Multivariate study of the psychosocial factors affecting public attitude towards organ donation].

INTRODUCTION: Organ transplantation is a therapy which depends on society for its development. The objectives here are: 1) to understand the structure of public opinion towards organ donation in the population aged over 15 years of age in our Community; 2) to analyse the psychosocial variables which affect this opinion and 3) to define the population profiles on this matter. MATERIALS AND METHODS: Random sample (n = 2.000) stratified for age, sex and geographical location (error for 95.5%, e +/- 2.24) to whom we apply a questionnaire about the psychosocial aspects of organ donation. Descriptive statistics, Student's t-test, Chi-squared test and logistical regression analysis. RESULTS: 63% have a favourable attitude towards organ donation, of which 11% have a donor's card. A statistical association has been observed between favourable public opinion and different psychosocial variables (p < 0.05), with some independent variables persisting in the multivariate analysis such as age, level of education (OR = 1.78), information given by family members (OR = 1.62), health workers (OR = 2.01) and talks in educational centres (OR = 2.13); previous experience with donation and transplantation (OR = 2.02), knowledge of the concept of brain death (OR = 1.4); partner's favourable opinion towards donation (OR = 2.6), being a blood donor (OR = 3), taking part in prosocial activities (OR = 1.6) and attitude towards incineration of the cadaver after death (OR = 1.8). CONCLUSIONS: The profile of a person who is against donation is of a man or woman, > 50 years of age, with primary studies or below, with no previous experience of the matter, who does not understand the concept of brain death nor their partner's opinion towards donation, who has not found out any information about donation through specialised forums, with an unfavourable opinion towards blood donation or pro-social activities and who is fearful of manipulation of the cadaver after death.

Adolescent↗
PubMed2004

Influence of different sources of information on attitude toward organ donation: a factor analysis.

OBJECTIVES: To determine media through which the population receives information on donation; to analyze the association between the sources of information and the psychosocial variables with respect to the opinion on donation; and to determine how each source of information influences this opinion. MATERIALS AND METHODS: A questionnaire on donation was administered to a random sample of 2000 persons stratified by age, gender, and geographical location, of whom 1143 respondents claimed to have no experience with donation and/or transplantation. A statistical analysis was done between the sources of information or the psychosocial variables or their co-variation to determine their specific impact on the population. RESULTS: The medium with the greatest impact on the population is television; the second factor is the press and radio; the third is magazines and talks with friends/family; the fourth is hoardings and posters, and campaigns about organ donation; and the last factor is information given by health professionals. In the factor analysis between sources of information and psychosocial variables, an association was observed between press, radio, and information given by health professionals and a higher education level; and between information provided by discussions in schools, by age, and a higher level of education. Sources of Information sources as that have a favorable effect on donation include discussions, (P = .0079), and information by health professionals (P < .0005) and by friends (P = .0132) and by family (P = .0044). CONCLUSIONS: Opinion on donation is more favorable among subjects who have received information on an individual basis and at specialized meetings. The only psychosocial variable associated with some sources of information is the level of education.

Adolescent↗
PubMed2003

Psychosocial profile in favor of organ donation.

INTRODUCTION: The lack of organ donation continues to be a major limiting factor in transplantation. Our aims are: (1) to define the psychosocial profile against organ donation, and (2) to determine the impact of a law on the procurement and transplantation of organs based on "presumed consent" in the population. MATERIALS AND METHODS: The population in this study (n = 2000) was randomly selected and stratified according to sex, age, and geographic localization. The attitude toward organ donation and transplantation was evaluated according to a questionnaire that probed psychosocial aspects of donation. Statistical comparisons were performed using the chi2 and logistic regression tests. RESULTS: The population attitude toward organ donation was favorable in 63% of subjects, unfavorable in 31%, and 6% did not respond. With regard to the law based on "presumed consent," only 24% of the population agreed with the law; 53% thought it was an abuse of authority. The population subgroup with a negative attitude to the law was characterized by: age over 40 years, low educational level, no previous experience with organ donation or transplant, no experience in prosocial activities, a refusal to accept cadaver manipulation or mutilation, and lack of knowledge of the brain-death concept. CONCLUSIONS: The psychosocial profile against donation is a person above 40 years with a low level of education who has never performed prosocial activities, did not have previous experience with organ donation or transplantation, displays no knowledge of the brain-death concept, and rejects cadaver manipulation. For these people a law based on "presumed consent" is considered an abuse of authority.

Adolescent↗
PubMed2003

Description of a new auxiliary heterotopic partial liver transplantation technique with portal vein arteriolization of applicability in heterotopic liver xenotransplantation.

OBJECTIVE: The aim of this study was to describe a new model of auxiliary heterotopic partial liver transplantation with portal vein arterialization. MATERIALS AND METHODS: Three standard hepatectomies were performed in pigs. The left lateral lobe was surgically resected and portal vein arteriolization constructed by an end-to-side "Y" anastomoses between the distal to the celiac axis aorta and the portal vein. RESULTS: The graft was placed in the left iliaca fossa using anastomoses of the donor infrahepatic inferior cava vein end-to-side to the host infrarenal inferior vein and the donor aortic stump with portal vein arteriolization end-to-side to the left iliac artery. After graft reperfusion, the 3 recipients showed intraoperative hypotension, which was treated with fluid administration and vasoactive drugs. At the end of the operation, the graft displayed normal arterial blood flow and good venous drainage. The donor liver graft appeared more red than the host liver, which was due to the increased arterial blood flow. One pig of 3 died at 24 hours after surgery, probably due to hypothermia. However, the other 2 pigs survived the procedure and remained stable. Echographic monitoring showed intrahepatic arterial expansion, which may be the result of high blood pressure due to the arteriolization procedure. CONCLUSIONS: We have developed a novel and easy to perform technique that diminishes the number of anastomoses and does not involve vessels from other organs.

Anastomosis, Surgical↗
PubMed2000

A novel subunit of yeast RNA polymerase III interacts with the TFIIB-related domain of TFIIIB70.

There is limited information on how eukaryotic RNA polymerases (Pol) recognize their cognate preinitiation complex. We have characterized a polypeptide copurifying with yeast Pol III. This protein, C17, was found to be homologous to a mammalian protein described as a hormone receptor. Deletion of the corresponding gene, RPC17, was lethal and its regulated extinction caused a selective defect in transcription of class III genes in vivo. Two-hybrid and coimmunoprecipitation experiments indicated that C17 interacts with two Pol III subunits, one of which, C31, is important for the initiation reaction. C17 also interacted with TFIIIB70, the TFIIB-related component of TFIIIB. The interaction domain was found to be in the N-terminal, TFIIB-like half of TFIIIB70, downstream of the zinc ribbon and first imperfect repeat. Although Pol II similarly interacts with TFIIB, it is notable that C17 has no similarity to any Pol II subunit. The data indicate that C17 is a novel specific subunit of Pol III which participates together with C34 in the recruitment of Pol III by the preinitiation complex.

Amino Acid Sequence↗
PubMed1999

A subunit of yeast TFIIIC participates in the recruitment of TATA-binding protein.

TFIIIC plays a key role in nucleating the assembly of the initiation factor TFIIIB on class III genes. We have characterized an essential gene, TFC8, encoding the 60-kDa polypeptide, tau60, present in affinity-purified TFIIIC. Hemagglutinin-tagged variants of tau60 were found to be part of TFIIIC-tDNA complexes and to reside at least in part in the downstream DNA-binding domain tauB. Unexpectedly, the thermosensitive phenotype of N-terminally tagged tau60 was suppressed by overexpression of tau95, which belongs to the tauA domain, and by two TFIIIB components, TATA-binding protein (TBP) and B"/TFIIIB90 (but not by TFIIIB70). Mutant TFIIIC was deficient in the activation of certain tRNA genes in vitro, and the transcription defect was selectively alleviated by increasing TBP concentration. Coimmunoprecipitation experiments support a direct interaction between TBP and tau60. It is suggested that tau60 links tauA and tauB domains and participates in TFIIIB assembly via its interaction with TBP.

DNA-Binding Proteins↗
PubMed1998

Tau91, an essential subunit of yeast transcription factor IIIC, cooperates with tau138 in DNA binding.

Transcription factor IIIC (TFIIIC) (or tau) is a large multisubunit and multifunctional factor required for transcription of all class III genes in Saccharomyces cerevisiae. It is responsible for promoter recognition and TFIIIB assembly. We report here the cloning and characterization of TFC6, an essential gene encoding the 91-kDa polypeptide, tau91, present in affinity-purified TFIIIC. Tau91 has a predicted molecular mass of 74 kDa. It harbors a central cluster of His and Cys residues and has basic and acidic amino acid regions, but it shows no specific similarity to known proteins or predicted open reading frames. The TFIIIC subunit status of tau91 was established by the following biochemical and genetic evidence. Antibodies to tau91 bound TFIIIC-DNA complexes in gel shift assays; in vivo, a B block-deficient U6 RNA gene (SNR6) harboring GAL4 binding sites was reactivated by fusing the GAL4 DNA binding domain to tau91; and a point mutation in TFC6 (tau91-E330K) was found to suppress the thermosensitive phenotype of a tfc3-G349E mutant affected in the B block binding subunit (tau138). The suppressor mutation alleviated the DNA binding and transcription defects of mutant TFIIIC in vitro. These results indicated that tau91 cooperates with tau138 for DNA binding. Recombinant tau91 by itself did not interact with a tRNA gene, although it showed a strong affinity for single-stranded DNA.

Amino Acid Sequence↗
PubMed1998

A chimeric subunit of yeast transcription factor IIIC forms a subcomplex with tau95.

The multisubunit yeast transcription factor IIIC (TFIIIC) is a multifunctional protein required for promoter recognition, transcription factor IIIB recruitment, and chromatin antirepression. We report the isolation and characterization of TFC7, an essential gene encoding the 55-kDa polypeptide, tau55, present in affinity-purified TFIIIC. tau55 is a chimeric protein generated by an ancient chromosomal rearrangement. Its C-terminal half is essential for cell viability and sufficient to ensure TFIIIC function in DNA binding and transcription assays. The N-terminal half is nonessential and highly similar to a putative yeast protein encoded on another chromosome and to a cyanobacterial protein of unknown function. Partial deletions of the N-terminal domain impaired tau55 function at a high temperature or in media containing glycerol or ethanol, suggesting a link between PolIII transcription and metabolic pathways. Interestingly, tau55 was found, together with TFIIIC subunit tau95, in a protein complex which was distinct from TFIIIC and which may play a role in the regulation of PolIII transcription, possibly in relation to cell metabolism.

Amino Acid Sequence↗
PubMed1997

A cryptic DNA binding domain at the COOH terminus of TFIIIB70 affects formation, stability, and function of preinitiation complexes.

TFIIIC-dependent assembly of yeast TFIIIB on class III genes unmasks a high avidity of TFIIIB for DNA. TFIIIB contains TATA-binding protein (TBP), TFIIIB90/B", and TFIIIB70/Brf1, which is homologous to TFIIB. Using limited proteolysis, we have found that the COOH terminus of TFIIIB70 (residues 510-596) forms a protease-resistant domain that binds DNA tightly as seen by Southwestern, DNase I footprinting, and gel shift assays. Consistent with a role for this DNA binding activity, preinitiation complexes were formed less efficiently with truncated TFIIIB70 lacking the COOH-terminal domain and displayed an increased sensitivity to heparin. B' (TFIIIB70 + TBP).TFIIIC.DNA complexes were also particularly unstable. In addition, TFIIIB.TFIIIC.DNA complexes containing truncated TFIIIB70 were impaired in promoting transcription initiation.

Amino Acid Sequence↗
PubMed1996

A suppressor of mutations in the class III transcription system encodes a component of yeast TFIIIB.

Class III genes depend on TFIIIB for recruitment of RNA polymerase III. Yeast TFIIIB is comprised of three components: TBP, TFIIIB70 and a 90 kDa polypeptide contained in the fraction B". We report the isolation of the yeast gene TFC7 which, based on genetic and biochemical evidence, encodes the 90 kDa polypeptide. TFC7 was isolated as a multicopy suppressor of temperature-sensitive mutations in the two largest subunits of TFIIIC. It is an essential gene, encoding a polypeptide of 68 kDa migrating with an apparent size of approximately 90 kDa. In gel shift assays, recombinant TFC7 protein (rTFC7) alone did not bind detectably to DNA, or to the TFIIIC-DNA complex even in the presence of TBP or TFIIIB70, but it was required to assemble the TFIIIB-TFIIIC-DNA complex. The two-hybrid assay pointed to an interaction between TFC7 protein and tau 131, the second largest subunit of TFIIIC (that also interacts with TFIIIB70). rTFC7p can replace the B" component of TFIIIB for synthesis of U6 RNA in a system reconstituted with recombinant TBP and TFIIIB70 polypeptides and highly purified RNA polymerase III. Surprisingly, specific transcription of the SUP4 tRNATyr gene promoted by rTFC7p was much weaker than with B". An additional factor activity, provided by the recently identified TFIIIE fraction, was required to restore control levels of transcription.

Amino Acid Sequence↗
PubMed1995

Complex interactions between yeast TFIIIB and TFIIIC.

Transcription of yeast class III genes requires the sequential assembly of the general transcription factors TFIIIC and TFIIIB, and of RNA polymerase III, into an initiation complex composed of at least 25 polypeptides. The 70-kDa subunit of TFIIIB (TFIIIB70) is central in this network of interactions as it contacts both TATA-binding protein and a subunit of polymerase III. We show here that the TATA-binding protein interacts with the carboxyl-terminal part of TFIIIB70. TFIIIB70 also contacts TFIIIC (factor tau) via its tau 131 subunit. The protein domains of tau 131 and TFIIIB70 involved in this interaction, either positively or negatively, were mapped using the two-hybrid system. We provide evidence that intramolecular interactions mask functional domains in both polypeptides.

Cloning, Molecular↗