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C Ayuso

Publications and source records attributed to C Ayuso.

At least 109 records · Page 6Linked to original sources
PubMed1995

Retinitis pigmentosa in Spain. The Spanish Multicentric and Multidisciplinary Group for Research into Retinitis Pigmentosa.

Retinitis pigmentosa is a term commonly given to a group of inherited and progressive disorders which affect the photoreceptors of the retina. As part of an ongoing research programme throughout Spain, clinical, epidemiological, and genetic studies have been carried out on these diseases. Here, we report the relative frequencies of the different genetic types in 503 non-syndromic and 89 syndromic RP families of Spanish origin. The most frequent syndromic RP forms were Usher syndrome type 1 (20/89 families = 30%) and Usher syndrome type 2 (44 families = 49%). Among non-syndromic RP forms, 12% were autosomal dominant, 39% autosomal recessive and 4% X-linked. Forty-one percent were isolated or simplex cases and in 4% the genetic type could not be established.

Female↗
PubMed1995

Polymorphic variations in peripherin-RDS gene in the Spanish population.

The authors report a study of polymorphisms in the peripherin-RDS gene in 21 Spanish families affected with Autosomal Dominant Retinitis Pigmentosa and 56 unrelated normal individuals. We found 3 variants in first exon and nine variants in the third exon in an SSCP analysis, all corresponding to different previously described polymorphisms.

Base Sequence↗
PubMed1994

Identification of a novel rhodopsin mutation (Met-44-Thr) in a simplex case of retinitis pigmentosa.

Retinitis pigmentosa (RP) is a group of genetically heterogeneous retinal degenerations that can be autosomal dominant (ADRP), autosomal recessive (ARRP), or X-linked. Approximately 30% of ADRP patients show point mutations or small deletions in the rhodopsin gene. However, over 50% of the RP patients are simplex cases (sporadic). Screening for mutations in the rhodopsin gene of 33 patients with simplex RP by denaturing gradient gel electrophoresis (DGGE) was carried out. One patient, with D-type (diffuse) RP and consanguineous parents, showed an altered electrophoretic pattern for the 5' half of exon 1. Direct sequencing revealed a new mutation ATG to ACG in codon 44; this predicts a change of Met-44-Thr in rhodopsin. The position and amino acid substitution suggest that this mutation causes the RP phenotype. Implications for genetic counselling are discussed.

Adolescent↗
PubMed1994

Phase II study of transarterial embolization in European patients with hepatocellular carcinoma: need for controlled trials.

Our uncontrolled phase II study was aimed at assessing the efficacy of transarterial embolization in patients with hepatocellular carcinoma and to determine the parameters associated with a favorable response to treatment, improved survival or both. Fifty consecutive patients (25 corresponding to Okuda's stage I and 25 to stage II) with hepatocellular carcinoma (41 being multinodular or massive) were included. Transarterial embolization induced a self limited postembolization syndrome that was well tolerated. Nevertheless, three patients died shortly after the procedure because of tumor progression (two cases) or progressive liver failure. A favorable response (extensive necrosis with reduction of tumor area greater than 50%) was achieved in 81% of the cases, and this result was independently (p < 0.05) related to a preserved performance status and to a lower alpha-fetoprotein concentration. The survival of the patients at 1 and 2 yr was 65% and 38%, respectively, better than the expected survival according to a mathematical model obtained from a historical series of untreated cases (42% and 20%, respectively). Cox regression analysis disclosed that both a favorable therapeutic response and a preserved physical condition (reflected by performance status of 0 or 1) were independently associated with better survival (regression coefficient -2.248 and 0.869, respectively). These data indicate that transarterial embolization has a marked antitumoral effect in patients with inoperable hepatocellular carcinoma and that the therapeutic success is associated with improved survival. Nevertheless, because the potential benefit for survival observed in this uncontrolled study appears to be moderate, prospective controlled trials to ascertain the real usefulness of this therapeutic approach are mandatory.

Aged↗
PubMed1994

[The gene responsible for Huntington's disease in Spanish families: its diagnostic value and the relation between trinucleotide expansion and the clinical characteristics].

We have studied 77 patients from 38 families with Huntington's disease (HD) analyzing the genes trinucleotide repeats (CAG)n; we have compared the results with those of 154 chromosomes from control population. Patients with HD range from 39 to 70 repeats while healthy patients have between 12 and 36 repeats. These results show the great feasibility of this genetic test. We do not have found a correlation between expansion's repeats and age of onset except for young people with the disease; in these cases we have found high level of expansions (more than 65) that could be a prognostic parameter of the disease.

Adolescent↗
PubMed1993

Localization of an autosomal dominant retinitis pigmentosa gene to chromosome 7q.

Retinitis pigmentosa is a group of clinically and genetically heterogeneous retinopathies and a significant cause of worldwide visual handicap. We have typed DNA from members of a Spanish family segregating an autosomal dominant form of retinitis pigmentosa (adRP) using a large series of simple sequence polymorphic markers. Positive two-point lod scores have been obtained with fifteen markers including D7S480 (theta max = 0.00, Zmax = 7.22). Multipoint analyses using a subset of these markers gave a lod score of 7.51 maximizing at D7S480. These data provide definitive evidence for the localisation of an adRP gene on chromosome 7q, and highlight the extensive genetic heterogeneity that exists in the autosomal dominant form of this disease.

Adolescent↗
PubMed1993

Treatment of small hepatocellular carcinoma in cirrhotic patients: a cohort study comparing surgical resection and percutaneous ethanol injection.

This study was intended to compare the survival rates of two contemporary cohorts of patients with solitary hepatocellular carcinomas < or = 4 cm subjected to surgical resection (n = 33) or percutaneous ethanol injection (n = 30). Outcomes in a third cohort, 21 patients with hepatocellular carcinoma who underwent orthotopic liver transplantation, were also assessed. Surgical and ethanol-treated patients were similar with regard to age and tumor stage, differing only in liver function; 30 of the 33 surgical patients were of Child-Pugh class A, whereas only 7 of the 30 ethanol-treated patients were of class A (p < 0.05). Surgical resection was successful in 30 cases; ethanol injection achieved initial success in 23 patients. Tumor recurrence rate at 2 yr was 45% in the surgical group and 66% in the ethanol group. The difference was significant only for cases with tumors between 3 and 4 cm. Despite poorer liver function, the 1-, 2-, 3- and 4-yr survival rates of ethanol-treated patients (83%, 66%, 55% and 34%, respectively) were not different from those of surgically treated patients (81%, 73%, 44% and 44%, respectively). The 1- and 2-yr survival rates of patients given liver transplants were 81% and 66%, without tumor recurrence, after 16-mo follow-up. These data confirm that ethanol injection is a useful treatment for patients with solitary small hepatocellular carcinomas and suggest that surgical resection and liver transplantation may achieve better results only after strict candidate selection to reduce mortality and tumor recurrence during follow-up.

Actuarial Analysis↗
PubMed1992

Tumor size determines the efficacy of percutaneous ethanol injection for the treatment of small hepatocellular carcinoma.

This study was aimed at defining the therapeutic value of percutaneous ethanol injection in patients with solitary hepatocellular carcinoma less than 4 cm. Ultrasound-guided ethanol injection was performed in 24 cirrhotic patients (9 Child A, 10 Child B and 5 Child C), with hepatocellular carcinoma not suitable for surgical treatment. Its efficacy was assessed by repeated ultrasound, computed tomography and tumor biopsy during a follow-up ranging between 4 and 41 mo. Ethanol injection did not achieve a complete tumor necrosis in five cases after a minimum of 12 injections. Seven of the remaining 19 cases, with initial success, have shown recurrence during follow-up, thus resulting in 50% success rate, which was significantly related to baseline tumor size. The six patients with nodules less than 2 cm achieved a complete response, whereas this was recorded in 2 of the 7 with tumor size between 2 and 3 cm, and in only 1 of the 11 cases between 3 and 4 cm. The 1- and 2-yr survival of Child's A and B patients was 87% and 70%, respectively. These results indicate that percutaneous ethanol injection is a useful treatment for hepatocellular carcinoma, especially in tumors less than 3 cm. The high survival rate among patients with nonadvanced liver disease suggests that this therapeutic approach can be considered an alternative approach to surgical resection for tumors smaller than 3 cm.

Aged↗
PubMed1992

Intestinal tuberculosis in AIDS.

The radiological appearance of intestinal tuberculosis (IT) in six patients with AIDS is presented. Involvement of the ileocecal segment (five cases), cecum (four cases), and duodenum (one case) was seen on computed tomographic (CT) or barium studies. There were no significant differences in radiological manifestations of IT among patients with or without AIDS, but all six patients had an advanced stage of their disease at the time of diagnosis.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Surgical resection and survival in Western patients with hepatocellular carcinoma.

In a retrospective study the survival of 28 patients with hepatocellular carcinoma, 25 of them with underlying cirrhosis, submitted to surgical resection was compared with the survival of 28 untreated patients, matched for variables known to bear independent prognostic value and therefore sharing the same baseline prognosis. Diagnosis was made in the same time period for both groups of patients. In addition, to further evaluate the effects of tumor resection on survival, the outcome of operated patients was also compared to their expected survival. This was derived from a mathematical model which takes into account the regression coefficients of the variables previously shown to be independently related to the survival of untreated patients with hepatocellular carcinoma. The median survival for resected patients was 27.1 months, which was significantly better than untreated controls (12.4 months; p less than 0.003). Median survival for patients submitted to resection and with tumors smaller than 5 cm was 35.8 months, while the median survival for untreated cases was 14.6 months p less than 0.0005. The comparison of observed survival (82% at one year and 73% at two years) and statistically expected survival (58% and 34%, respectively) further indicated that surgical resection effectively improves prognosis in Western patients with hepatocellular carcinoma. Thus, early detection of small tumors in the population at risk appears to be justified.

Aged↗
PubMed1992

Autosomal dominant retinitis pigmentosa (adRP): exclusion of a gene from three mapped loci provides evidence for the existence of a fourth locus.

Retinitis Pigmentosa (RP) is a group of inherited retinopathies which affect approximately 1 in 4,000 individuals. The disorder can be classified on the basis of inheritance; dominant, recessive and X-linked forms have been well documented. The existence of genetic heterogeneity within autosomal dominant RP (adRP) had been previously demonstrated. As a result of extensive linkage studies in 2 large Irish families and 1 American pedigree three adRP genes have been mapped. adRP genes have been localised to chromosome 3q close to the rod photoreceptor gene, rhodopsin; to chromosome 6p close to another transmembrane photoreceptor gene, peripherin/RDS and to the pericentric region of chromosome 8, although the causative gene in this region has not yet been identified. Here we report the results of a linkage study in a Spanish family, who exhibit an early-onset form of adRP. The adRP gene segregating in this family has been excluded from the three known adRP loci on chromosomes 3q, 6p and 8 using a series of both intragenic microsatellite markers from the rhodopsin and peripherin/RDS genes and markers flanking the three known loci. These results provide definitive evidence for the existence of a fourth adRP locus, further emphasising the genetic heterogeneity that exists within adRP.

Chromosome Mapping↗
PubMed1992

Calcifications in the portal venous system: comparison of plain films, sonography, and CT.

We describe 10 patients with long-standing portal hypertension and calcifications in the splenoportal and mesenteric venous systems or collateral vessels. The patients were examined with abdominal plain films (n = 10), sonography (n = 10), and CT (n = 9). Calcium was seen on CT scans in nine cases, on sonograms in seven, and on abdominal plain films in five. Calcifications appeared to be located in the wall of the vein in all cases. Sites of detection included the main portal, splenic, superior mesenteric, coronary, and peripancreatic veins. CT was more sensitive than sonography, and both were more sensitive than plain films, in showing portal venous calcification. Detection of such calcifications may influence surgical or percutaneous therapy of portal hypertension.

Aged↗
PubMed1991

[Diagnosis of renal carcinoma in acquired cystic renal disease. Usefulness of echography in detection during subclinical phase].

BACKGROUND: The patients with end-stage renal disease on periodic hemodialysis often develop acquired cystic renal disease, and they have renal tumours more commonly than the normal population. METHODS: To evaluate the usefulness of echography for the evaluation of these lesions and the prevalence of acquired cystic renal disease and occult renal tumours in patients treated with hemodialysis during years, a prospective ultrasonographic study was carried out. To this end, renal echographic studies were performed in 43 asymptomatic patients treated with periodic hemodialysis during 5 years or more. Patients with renal polycystic disease were excluded from the study. RESULTS: The overall prevalence of acquired cystic renal disease was 86%. It was higher in males (96%) than in females (70%). Two patients (4.6%) had malignant renal tumours. CONCLUSIONS: In view of the high prevalence of tumours in acquired cystic renal disease, it is suggested that periodic echographic studies should be carried out in patients with end-stage renal disease treated with hemodialysis during years to detect renal carcinoma in subclinical stage.

Adolescent↗
PubMed1990

Ring chromosome 6: clinical and cytogenetic behaviour.

Several investigators have reported in vitro instability of ring chromosomes. We have evaluated the clinical and cytogenetic course over 8 years in a patient with ring chromosome 6 and found stability in this ring chromosome. The different cell lines remained constant, and the phenotype showed little variation. This syndrome seems to be related to the deletion in the ring rather than to its instability.

Adolescent↗
PubMed1990

Study of the parental origin of sexual aneuploidy in ten families using RFLPs.

We have studied 10 families with sexual aneuploidy by means of recombinant DNA techniques. The X linked probes were F814 (DXS52), FIX (FVIII gene), pert 87.15 (DXS164), L754 (DXS84) and 47Z (DXYS5). The observed banding patterns allowed us to determine the parental origin of such aneuploidy in nine of our cases. It was paternal in seven cases and maternal in two.

Cells, Cultured↗
PubMed1989

Diagnostic accuracy of fine-needle aspiration biopsy in patients with hepatocellular carcinoma.

The present study was undertaken to investigate the diagnostic usefulness of fine-needle aspiration biopsy (FNAB) in a large series of patients with hepatocellular carcinoma (HCC) seen over a 1-year period. During 1986, ultrasonographically guided percutaneous FNAB was performed in 72 patients with suspected HCC. A final diagnosis of HCC was made in 58 patients. The presence or absence of HCC was ascertained by histological examination and/or by other diagnostic procedures (alpha 1-fetoprotein, computed tomography, arteriography) and by clinical follow-up (repeated ultrasonographic controls) and/or by surgery or necropsy. A total of 61 FNABs were carried out in these 58 patients. Only 42 (69%) of the 61 FNABs allowed the diagnosis of HCC. This moderate diagnostic sensitivity was not related to tumor size. Only one false positive result was observed in the non-HCC group. Therefore, the diagnostic specificity of FNAB for HCC was 93%, with a positive predictive value of 97% and a negative predictive value of 40%. These results show that FNAB is a useful diagnostic technique in patients with HCC. However, these data also show that there is a large proportion (31%) of subjects with false negative results. Therefore, we suggest that further efforts should be made to improve the diagnostic accuracy of this procedure.

Adult↗