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J Ponce

Publications and source records attributed to J Ponce.

At least 37 records · Page 2Linked to original sources
PubMed1998

Characterization of the 5' region of the rat brain glycine transporter GLYT2 gene: identification of a novel isoform.

We have identified two alternative 5' ends for the GLYT2 glycine transporter in rat brain DNA by using rapid amplification of cDNA ends (RACE) analysis. Study of the genomic DNA revealed that the isoform diversity is generated by alternative use of exons 1a or 1b, respectively. Upon translation, the mRNA corresponding to the novel isoform GLYT2b would yield a protein five amino acids longer than the previously characterized isoform GLYT2a. Both forms display similar regional distribution and kinetics characteristics. However, whereas GLYT2a is able to actively accumulate glycine into transfected COS cells, GLYT2b seems only to exchange (or release) glycine.

Alternative Splicing↗
PubMed1998

[Free bowel perforation as the onset and as a complication in the evolution of crohn's disease].

Free bowel perforation is a relatively infrequent complication of Crohn's disease. It may present during the evolution of the disease or, occasionally, in the onset of the same and may involve the small intestine or colon. We herein present 4 cases, three of ileal localization and one of colonic localization. In one of the 3 former cases and the latter case perforation took place prior to diagnosis of the disease. Review of the literature was performed with respect to the frequency, pathogenesis and characteristics of this complication and the importance of determined diagnostic techniques such as echography and CAT in addition to the most adequate treatment are commented upon.

Adolescent↗
PubMed1998

Quality of life during acute and intermittent treatment of gastro-oesophageal reflux disease with omeprazole compared with ranitidine. Results from a multicentre clinical trial. The European Study Group.

AIMS: To investigate quality of life in patients with gastro-oesophageal reflux disease. PATIENTS: A series of 704 patients were randomised to treatment with ranitidine 150 mg bd, omeprazole 10 mg om or omeprazole 20 mg om for 2 weeks. Asymptomatic/mildly symptomatic patients were followed for 12 months. METHODS: The Psychological General Well-Being index and the Gastrointestinal Symptom Rating Scale were completed before and during short-term and intermittent treatment. RESULTS: The quality of life response rate was > 80%. The majority of the patients receiving omeprazole 20 mg om (55%) had symptom relief after 2 weeks despite the fact that more patients on ranitidine required 4 weeks' treatment and an increased dose. There was no difference in the reflux dimension of Gastrointestinal Symptom Rating Scale between treatments in the initial treatment phase, but the total Gastrointestinal Symptom Rating Scale score improved significantly more on omeprazole 10 mg om than on ranitidine 150 mg bd (p = 0.006). Both doses of omeprazole improved the total Psychological General Well-Being score more than ranitidine (omeprazole 10 mg om versus ranitidine 150 mg bd, p = 0.005, omeprazole 20 mg om versus ranitidine 150 mg bd, p = 0.031). During follow-up, relapsing patients returned to pre-treatment symptom and well-being scores, but these dimensions were restored after treatment. CONCLUSION: The quality of life is impaired in patients presenting with reflux symptoms. Irrespective of whether the patients presented with endoscopy positive or endoscopy negative reflux disease, treatment on demand improved the quality of life.

Adolescent↗
PubMed1998

[Significance of the determination of antineutrophil cytoplasmic antibodies (ANCA) in ulcerative colitis and Crohn's disease].

We have studied prospectively 126 consecutive patients recruited with a known diagnosis of ulcerative colitis (UC; n = 78) and Crohn's disease (CD; n = 48) for anti-neutrophil cytoplasmatic antibodies (ANCA) by indirect immunofluorescence (IFI). Forty-six percent of UC and 18% of CD patients were found positive. The sensitivity and specificity for UC diagnosis were 0.46 and 0.81, respectively. We evaluated the pattern of IFI exhibited (perinuclear: pANCA and cytoplasmatic: cANCA). cANCA was found in 77% of CD and in only 30% of UC patients (p = 0.01). Sera from all CD patients were positive at a 1:20 dilution (and not at higher dilution) and it occurred in only in 14 UC patients (30%). Positive sera were also tested to characterize the antigen specificity by enzyme-linked immunosorbent assay (ELISA) but the antigenic nature of ANCA could not be identified in most cases. No differences were found between ANCA positive and ANCA negative patients regarding colonic extension (UC) or colonic involvement (CD), activity and colectomy. We conclude that ANCA may be a helpful diagnostic test in UC patients but it not seems to be important as a marker of activity. ANCA positivity can reflect disease heterogeneity in UC patients, perhaps discriminating those with immunologic disturbances.

Adolescent↗
PubMed1998

[Study of gastric emptying by dual isotopes. Corrections due to contamination].

The evaluation of gastric emptying by the double isotope technique involves some methodologic conditioning. Among them contamination correction or interference in the energy windows of the activity of the two isotopes used in the marking of the solids and fluids of the test food are important. The results of an experiment in which a phantom was used to evaluate the contamination between indio 111 (DTPA-Ca111In) and technecium 99m (colloid99mTc). Three test studies were posteriorly performed in healthy volunteers and 27 studies in a control group (13 males, mean age of 33 years, mean body mass index 39.02 kg/m). In these studies the contamination was corrected with the acquisition, following an initial swallow of juice marked with 111In, of activity in the windows of both isotopes. The contamination of 111In (isotope of greatest radiation energy) in the window of 99mTc was 24% in the phantom and 20%, 23% and 26% in the three initial study tests. The mean contamination in the control group was of 22% with limits of 19% to 29% and a standard deviation of 3%. Despite the comparable results, the usefulness of the individualized contamination calculation in the studies of gastric emptying with dual isotope to minimize the methodologic errors of this technique is discussed.

Adult↗
PubMed1997

The glycine transporter GLYT2 is a reliable marker for glycine-immunoreactive neurons.

The glycine transporter GLYT2 is present in neurons of the spinal cord, the brain stem and the cerebellum. This localization is similar to that of glycine immunoreactivity, suggesting a causal relationship between GLYT2 expression and glycine distribution. In this report, we analyzed if such a relationship does exist by using neuronal cultures derived from embryonic spinal cord. GLYT2 was synthesized in a small subpopulation of neurons where it was targeted both to dendrites and to axons, being the axonal content higher than the dendritic one. At early stages in the development of cultured spinal neurons, the highest GLYT2 levels were found in the axonal growth cones. As the culture matured, immunoreactivity extended to the axonal shaft. Double-immunofluorescence experiments indicated a perfect co-localization of GLYT2 and glycine immunoreactivity in cultured neurons. Moreover, the concentration of glycine into neurons expressing GLYT2 was proportional to the concentration of the transporter. This observation was reproduced in GLYT2-transfected COS cells. These evidences indicate that the high content of glycine observed in some neurons in culture is indeed achieved by the concentrative task performed by GLYT2, and that GLYT2 can be used as a reliable marker for identification of glycine-enriched neurons.

Amino Acid Transport Systems, Neutral↗
PubMed1997

Analysis of the predictive value of clinical data in patients with suspected colonic disease.

OBJECTIVE: To develop guidelines for predicting colonic disease on the basis of clinical parameters. EXPERIMENTAL DESIGN: A prospective study of the clinical data prior to colonoscopy. On the basis of the endoscopic findings, the patients were divided into three diagnostic groups: absence of significant disease, significant benign disease and malignant disease. The patient population was divided randomly into two subgroups. The clinical data from one of them was used to build a database which, using Bayes' theorem, was compared with the variables from the other subgroup to predict the diagnosis for each patient. PATIENTS: A total of 336 patients (170 males and 166 females; mean age: 58 years; range: 15 to 87 years) were evaluated. RESULTS: When the endoscopic findings were grouped on the basis of their clinical importance, 211 patients (63%) belonged to the group without significant disease, 60 patients (18%) had significant benign disease and 65 (19%) presented a neoplastic disease. Of the 21 variables selected for use in the database, 6 showed statistically significant differences in terms of the absence or presence of malignant disease: age, absence of previous similar episodes, weight loss, rectal bleeding, lack of improvement and the presence of a mass on digital rectal examination. The predictive model differentiated patients with neoplasm from those without malignant disease, but was not capable of identifying differences among the latter. The model was useful for assessing the risk of malignant disease for each patient. CONCLUSIONS: The predictive model obtained is a useful tool for establishing the diagnosis and the priority in the performance of colonoscopy.

Adolescent↗
PubMed1996

Individual prediction of response to pneumatic dilation in patients with achalasia.

During nine years, 157 consecutive patients with achalasia have been dilated in our unit. First, the long-term effect of dilation on clinical status was evaluated. The probability of being in clinical remission eight years after first dilation was 51%. The pressure of the LES measured after dilation was highly predictive of the long-term clinical evolution. Second, a predictive model of the individual response to pneumatic dilation was developed and simplified. Therapy was effective in 80% of the patients, after one to four dilations. Younger age was the only factor significantly associated with ineffective therapy. Depending on the prognosis of the outcome calculated with the predictive model, patients were classified in groups of risk that showed a different rate of ineffective, therapy. In the simplified model, age < or = 20 years, male gender, esophageal body diameter < or = 3 cm, esophageal body basal pressure > 15 mm Hg, and pressure of the lower esophageal sphincter > 30 mm Hg were predictors of a poor response to dilation. We conclude that pneumatic dilation is an effective therapy for achalasia. A predictive model was useful to classify the patients in groups with a different risk for ineffective dilation. A simplification of this model could be used to predict the response to dilation.

Adolescent↗
PubMed1996

Total antioxidant capacity of human seminal plasma.

Although the importance of seminal plasma in the protection of spermatozoa against reactive oxygen species is well known, only a few studies have investigated its antioxidative properties and the possible relationship between infertility and plasmatic antioxidant defences. The aim of the present study was to assess the status of the total non-enzymatic antioxidant defences of human seminal plasma. Semen samples were obtained from 101 patients consulting for infertility and 15 fertile donors. A total reactive antioxidant potential (TRAP) in seminal plasma was determined by luminol-chemiluminescence. The relationship of seminal TRAP values to lipid peroxidation was also evaluated. Our results show that semen samples from fertile controls show total antioxidant capacity at higher frequency and value than equivalent samples from suspected subfertile men. This fact as well as the inverse relationship observed between antioxidant capacity and lipid peroxidation potential strongly suggest that impaired antioxidant defences may play a role in infertile disorders.

Antioxidants↗
PubMed1996

Achalasia-like syndrome as the first manifestation in a patient with CREST syndrome.

We report a case of oesophageal disease as the first manifestation in a patient with CREST syndrome. A 46-year-old man with achalasia-like syndrome developed CREST syndrome 4 years later. A pneumatic dilatation of the cardia was performed. After pneumatic dilatation the dysphagia and regurgitation disappeared but the patient developed reflux oesophagitis. Four years after diagnosis of oesophageal disease he presented with a clinical picture of CREST syndrome. An acute ileus and constipation developed later. After receiving medical therapy with omeprazole and cisapride the patient is free of oesophageal symptoms and bowel movements are normal. Oesophageal disease is common in patients with limited and diffuse scleroderma, but to our knowledge achalasia-like syndrome has not been previously described as the first manifestation of the systemic disease.

Anti-Ulcer Agents↗
PubMed1996

[The clinical significance of the magnitude of esophageal dilatation in idiopathic achalasia].

The relationship between the diameter of the esophageal body and the clinical profile of the disease and response to treatment was analyzed in 151 patients with idiopathic achalasia by pneumatic dilation of the cardias. Of the 151 patients, 46 presented an esophageal diameter < or = 3 cm (group I), 78 a diameter > 3 cm up to a maximum of 5 cm (group II) and 27 presented a diameter > 5 cm (group III). The result of pneumatic dilatation of the cardias under endoscopic control was analyzed in 117 patients with a minimum follow up of one year after the last dilatation session. Of all the clinical parameters studied, significant statistical differences were only found in group III in respect to the time of symptom evolution and the presence of regurgitation. Manometric data in basal pressure of the esophageal body and in contraction wave width were lower in groups I and III, respectively. The remaining variables were similar in the three groups although group III showed a trend to older age and the frequency of pulmonary complications with lesser thoracic pain and registry of a strict pattern. Endoscopic pneumatic dilation carried out in all the cases was effective in 83% of the patients and was similar in the three study groups. The rate of complications (perforation) was also similar. The therapeutic efficacy of pneumatic dilatation was accompanied by a significant reduction in esophageal diameter. It was concluded that the increase in esophageal diameter in idiopathic achalasia is associated with chronological, clinical and functional parameters which suggest greater disease evolution but do not determine significant changes in the therapeutic response to endoscopic pneumatic dilatation.

Adolescent↗
PubMed1995

The lost laparoscopic stone. Potential for long-term complications.

Intraperitoneal gallstones left behind at laparoscopic cholecystectomy are not uncommon. Such stones have previously been thought to be harmless. We report three instances of delayed intra-abdominal infection and/or inflammation related to these misplaced gallstones. All three patients presented months postoperatively with vague abdominal complaints. Computed tomography revealed inflammatory foci involving intraperitoneal gallstones. All patients required percutaneous or operative drainage of the collections. Every effort should be made to locate and remove "spilled" gallstones at the time of laparoscopic cholecystectomy.

Abdomen↗
PubMed1995

tinman, a Drosophila homeobox gene required for heart and visceral mesoderm specification, may be represented by a family of genes in vertebrates: XNkx-2.3, a second vertebrate homologue of tinman.

tinman is a Drosophila Nk-homeobox gene required for heart and visceral mesoderm specification. Mutations in tinman result in lack of formation of the Drosophila heart, the dorsal vessel. We have isolated an Nk-homeobox gene from Xenopus laevis, XNkx-2.3, which appears by sequence homology and expression pattern to be a homologue of tinman. The expression pattern of XNKx-2.3 both during development and in adult tissues partially overlaps with that of another tinman homologue, Csx/NKx-2.5/XNkx-2.5. We have found that embryonic expression of both XNkx-2.3 and XNkx-2.5 is induced at a time when cardiac specification is occurring. XNkx-2.3 is expressed in early cardiac primordia before the expression of a marker of cardiac differentiation. XMLC2, as well as in pharyngeal endoderm. In adult tissues, XNkx-2.3 is expressed in the heart and several visceral organs. As the helix-loop-helix factor Twist is thought to regulate tinman expression in Drosophila, we have compared the expression of XNkx-2.3 and Xtwist during embryonic development in Xenopus. There appears to be no overlap in expression patterns of the two RNAs from the neurulae stages onward, the first time at which the RNAs can be visualized by in situ hybridization. The overlapping expression patterns of XNkx-2.3 and mNkx-2.5/XNkx-2.5 in conjunction with evidence presented here that other Nk-homeodomains are expressed in adult mouse and Xenopus heart suggests that tinman may be represented by a family of genes in vertebrates.

Alleles↗
PubMed1995

[Lansoprazol].

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2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1995

[Do patients with duodenal ulcer transmit Helicobacter pylori to their relatives?].

The prevalence of IgG antibodies to Helicobacter pylori was determined with an enzyme-linked immunosorbent assay in 80 families who lived together with 40 duodenal ulcer patients in whom Helicobacter pylori had been cultured from a gastric biopsy (34 spouses, 31 children, 10 parents, 4 sisters and 1 brother) and in 112 controls from the same habitat and with similar age. The antibodies were positive in 38.4% of the relatives and in 36.6% of the controls, the difference was not significant. Among spouses of patients, 38.4% of those aged 25-39 years and 66.6% of those aged 40-67 years were positive, whereas controls showed a 29.2% and a 58.3% of positives respectively. The differences between both groups were not significant. Among children, 17.2% were positive and in parents 50%, whereas among controls with a similar age 26.3% and 62.5% respectively were positive. The differences between relatives and controls were not significant. We conclude that in our environment among consanguineous families living together and between spouses, person-to-person spread of Helicobacter pylori does not usually occur or it happens uncommonly.

Adolescent↗
PubMed1995

[Uroflowmetric nomogram in the adult population of Canary Islands].

In order to know the uroflowmetric values of our healthy population, a uroflowmetry was made to 214 healthy subjects of both sexes. 75% of our group of volunteers collected mictional volumes under 300 ml. with no differences either by age or sex. The corresponding nomograms, in the form of percentile, for peak and mean flow in both sexes, were created. We found a progressive increase of peak and mean flow values with regard to mictional volume. Time to peak flow is shorter in women than in men. Volume at peak flow represents under 50% of total mictional volume. No significant differences in the uroflowmetric data of our healthy population and those from Anglo-Saxon authors was found.

Adult↗