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J Seoane

Publications and source records attributed to J Seoane.

At least 19 recordsLinked to original sources
PubMed1998

Flow cytometric analysis of nuclear DNA content in oral leukoplakia.

DNA ploidy has been studied in 31 paraffin-embedded specimens of oral leukoplakia and in 10 specimens of oral leukoplakia that have undergone malignant transformation after a 5-year observation period. Three out of 31 specimens (9.7%) showed an aneuploid DNA pattern, with DNA indices of 1.17, 1.28 and 1.32. It was not possible to establish a statistically significant difference of DNA ploidy related to the presence or absence of dysplasia. One out of the 10 oral leukoplakias that underwent malignant transformations had a multiploid pattern with DNA indices of 1.44 and 2.37. In this study the DNA index has not proved to be of value in the identification of dysplastic leukoplakia among the non-dysplastic ones.

Aneuploidy↗
PubMed1998

[Prospective 3-month study of intravascular catheter complications in HIV-infected patients: relation between phlebitis and infection].

BACKGROUND: The aim of this study was to evaluate the etiology of phlebitis (chemical or infectious) and the prevalence of infections related to intravascular catheters (IRIC) in patients with HIV infection admitted to a 22-bed Infectious Disease Unit with a high rate of HIV infection. MATERIAL AND METHODS: A 3-month prospective study from November 1, 1994 to January 31, 1995 was carried out following a formula for data collection of all the intravenous catheters used during that time period. Cultures of the catheters withdrawn on Wednesdays and those with signs of phlebitis were performed. RESULTS: One hundred fifty-two intravenous catheters in 71 patients with HIV infection with a mean age of 37 years (range: 21-73) and mean hospital stay of 10.2 days were reported. During the study period 42 phlebitis were produced, of which 37 catheters (7 central and 30 peripheral) were processed. Of the 37 phlebitis processed, 29 (78.9%) were considered to be of physiochemical origin. Of the 21 catheters withdrawn Wednesday, 18 were processed, 8 with phlogotic signs, 2 with IRCI, equivalent to 1.9 IRCI/100 days of catheterization. During the study period no local or severe systemic infections related to the catheter were reported. Staphylococcus epidermidis was the organism involved in all the cases of IRCI. CONCLUSIONS: Despite the high number of immunosuppressed patients in related to HIV infection, a greater incidence of IRCI was not found in these patients. The most frequent cause of phlebitis by catheter was of chemical origin.

Adult↗
PubMed1997

Metabolic impact of adenovirus-mediated overexpression of the glucose-6-phosphatase catalytic subunit in hepatocytes.

Glucose-6-phosphatase (G6Pase) catalyzes the hydrolysis of glucose 6-phosphate (Glu-6-P) to free glucose and, as the last step in gluconeogenesis and glycogenolysis in liver, is thought to play an important role in glucose homeostasis. G6Pase activity appears to be conferred by a set of proteins localized to the endoplasmic reticulum, including a glucose-6-phosphate translocase, a G6Pase phosphohydrolase or catalytic subunit, and glucose and inorganic phosphate transporters in the endoplasmic reticulum membrane. In the current study, we used a recombinant adenovirus containing the cDNA encoding the G6Pase catalytic subunit (AdCMV-G6Pase) to evaluate the metabolic impact of overexpression of the enzyme in primary hepatocytes. We found that AdCMV-G6Pase-treated liver cells contain significantly less glycogen and Glu-6-P, but unchanged UDP-glucose levels, relative to control cells. Further, the glycogen synthase activity state was closely correlated with Glu-6-P levels over a wide range of glucose concentrations in both G6Pase-overexpressing and control cells. The reduction in glycogen synthesis in AdCMV-G6Pase-treated hepatocytes is therefore not a function of decreased substrate availability but rather occurs because of the regulatory effects of Glu-6-P on glycogen synthase activity. We also found that AdCMV-G6Pase-treated-cells had significantly lower rates of lactate production and [3-3H]glucose usage, coupled with enhanced rates of gluconeogenesis and Glu-6-P hydrolysis. We conclude that overexpression of the G6Pase catalytic subunit alone is sufficient to activate flux through the G6Pase system in liver cells. Further, hepatocytes treated with AdCMV-G6Pase exhibit a metabolic profile resembling that of liver cells from patients or animals with non-insulin-dependent diabetes mellitus, suggesting that dysregulation of the catalytic subunit of G6Pase could contribute to the etiology of the disease.

Adenoviridae↗
PubMed1997

[Photochemotherapy in the treatment of oral erosive lichen planus. Letter].

Photochemotherapy with 8-methoxypsoralenes and PUVA has been found to be effective in the treatment of superficial skin inflammations, such as lichen planus. However, there is little bibliography on the treatment of oral lichen planus with PUVA. A case of oral erosive lichen planus was treated with oral psoralenes (0.6 mg/kg body weight) two hours before ultraviolet exposure. Twenty sessions were held, three weekly, for a total cumulative dose of 35.9 J/cm2. After treatment concluded, clinical symptoms and erosive lesions disappeared. PUVA therapy may be useful for severe forms of erosive oral lichen planus that do not respond to conventional treatment.

Drug Therapy↗
PubMed1997

Assessment of dental students' ability to recognise precancerous lesions and conditions.

The role of dentists in both primary (promoting a healthier lifestyle) and secondary (early diagnosis) prevention of oral cancer is undeniable, and becomes particularly important as oral cancer is thought to be preceded by premalignant lesions or conditions in about one half of the cases. In these situations, there is the possibility for an early diagnosis which will definitively influence the survival rate. Thus, it is an undergraduate educational objective related to secondary prevention of oral cancer to increase the efficacy of screening of precancerous lesions/conditions. A questionnaire with 38 clinical cases including 16 benign lesions, 9 malignant lesions and 13 precancerous lesions or conditions was applied voluntarily to 3rd, 4th and 5th year University of Santiago de Compostela dental students on April 1996. The participation rate was 90% of the 3rd-year students, 60% in 4th-year class, and 50% of the 5th-year group. The agreement in the diagnosis with a panel of experts reached 81.45% for 5th-year students. Students of 3rd- and 4th-year scored lower percentages, probably due to the rarity of some of the conditions in our area. 5th-year students scored significantly higher values than 3rd- and 4th-year students.

Clinical Competence↗
PubMed1996

Glucose 6-phosphate produced by glucokinase, but not hexokinase I, promotes the activation of hepatic glycogen synthase.

In a previous study (O'Doherty, R. M., Lehman, D. L., Seoane, J., Gómez-Foix, A. M., Guinovart, J. J., and Newgard, C.B. (1996) J. Biol. Chem. 271, 20524-20530), we demonstrated that adenovirus-mediated overexpression of glucokinase but not hexokinase I has a potent enhancing effect on glycogen synthesis in primary hepatocytes. In an effort to understand the underlying mechanism of this differential effect of the two hexokinase isoforms, we have investigated changes in key intracellular metabolites and the activation state of glycogen synthase in cells treated with recombinant adenoviruses expressing the liver isoform of glucokinase (AdCMV-GKL) or hexokinase I (AdCMV-HKI). Glucose 6-phosphate (Glu-6-P) levels are elevated from approximately 1.5 nmol/mg protein to 8-10 nmol/mg protein in both AdCMV-GKL- and AdCMV-HKI-treated hepatocytes as glucose is raised from 1 to 5 mM, levels four times higher than those in untreated cells. In AdCMV-GKL-treated cells, Glu-6-P continues to accumulate at glucose levels greater than 5 mM, reaching a maximum of 120 nmol/mg protein in cells incubated at 25 mM glucose, a value 10 and 50 times greater than the maximal levels achieved in AdCMV-HKI-treated and untreated cells, respectively. In parallel with the changes observed in Glu-6-P levels, increases in UDP-Glc in AdCMV-HKI- and AdCMV-GKL-treated cells were most pronounced at low (1-5 mM) and high (25 mM) glucose levels, respectively. Despite the significant increases in Glu-6-P and UDP-Glc achieved in AdCMV-HKI-treated cells, only AdCMV-GKL-treated cells exhibited increases in glycogen synthase activity ratio and translocation of the enzyme from a soluble to a particulate form relative to untreated control cells. We conclude that Glu-6-P produced by overexpressed glucokinase is glycogenic because it effectively promotes activation of glycogen synthase. Glu-6-P produced by overexpressed hexokinase, in contrast, appears to be unable to exert the same regulatory effects, probably due to the different subcellular distribution of the two glucose-phosphorylating enzymes.

Animals↗
PubMed1996

Differential metabolic effects of adenovirus-mediated glucokinase and hexokinase I overexpression in rat primary hepatocytes.

The first step of glucose metabolism is the phosphorylation of glucose, catalyzed by the hexokinase family of enzymes. To address the metabolic impact of increasing glucose phosphorylation capacity in liver, rat primary hepatocytes were treated with recombinant adenoviruses containing the cDNAs encoding either rat liver glucokinase (AdCMV-GKL) or rat hexokinase I (AdCMV-HKI). Maximal glucose phosphorylation in AdCMV-GKL- and AdCMV-HKI-treated hepatocytes was increased 7.1 +/- 1.2- and 6.3 +/- 0.8-fold, respectively, over hepatocytes treated with an adenovirus expressing beta-galactosidase. Glucose usage (measured with 3 and 20 m 2-[3H]glucose and 5-[3H]glucose) was significantly increased in AdCMV-GKL-treated cells preincubated in 1 or 25 mM glucose. Treatment of hepatocytes with AdCMV-HKI also caused enhanced glucose utilization, but the increases were smaller and were less apparent in cells preincubated in high (25 mM) glucose. AdCMV-GKL-treated hepatocytes incubated for 48 h in the presence of variable glucose concentrations had glycogen levels that were maximally 15.0 +/- 0. 6-fold greater than levels in corresponding control cells. AdCMV-HKI-treated hepatocytes incubated under similar conditions had unchanged glycogen levels relative to controls. In AdCMV-GKL-treated cells, lactate output was increased to a maximum of 3.0 +/- 0.4-fold (at 25 mM glucose), glucose oxidation was increased 3.5 +/- 0.3-fold, and triglyceride production was unchanged relative to untreated cells. Among these three parameters, only lactate production was increased in AdCMV-HKI-treated cells, and then only at low glucose concentrations. We conclude that overexpression of glucokinase has potent effects on glucose storage and utilization in hepatocytes and that these effects are not matched by overexpression of hexokinase I.

Adenoviridae↗
PubMed1995

Double staining of coomassie blue-stained polyacrylamide gels by imidazole-sodium dodecyl sulfate-zinc reverse staining: sensitive detection of coomassie blue-undetected proteins.

The sensitivity, simplicity, and relative rapidity of Coomassie blue staining have made this technique the method of choice for routine detection and quantitative analysis of gel electrophoresis-separated protein bands in many applications. To extend the usefulness of this technique, we have developed a new double-staining method for visualizing SDS-PAGE-separated protein bands that were undetected by Coomassie blue staining of the gel. Coomassie blue-stained gels are washed in distilled water (15 min, two times) and then subjected to imidazole-zinc reverse staining. As a result of the method, a homogeneous white-stained background is generated and two types of protein bands can be observed: (a) typical Coomassie blue-stained bands, which appear superposed on larger transparent bands; and (b) reverse-stained (transparent) bands, which were previously undetected by the Coomassie blue staining. The method is rapid, simple, and reproducible and double-staining gels can be kept in distilled water for months without loss of the protein pattern. The overall sensitivity is high (e.g., 1.6 ng for recombinant streptokinase, 47 kDa) over a wide range of protein molecular weights (10 to 100 kDa) and independent of the degree of Coomassie blue destaining of the gel. Furthermore, a mechanism offering a consistent explanation for the role of imidazole, SDS, and zinc in the reverse staining of gels, particularly after Coomassie blue staining is proposed.

Electrophoresis, Polyacrylamide Gel↗
PubMed1992

[Manometric changes induced by antireflux surgery (Nissen) and its relation to pH measurement and clinical findings. An analysis 6 months after the intervention].

We analyzed the preoperative ambulatory 24 hour ph-metric and manometric characteristics in a group of 20 patients treated surgically for gastroesophageal reflux (PGER) by Nissen fundoplication. At 6 months post-surgery they were reevaluated instrumentally (manometric and 24 hour ph-metry) and clinically. All ph-metric parameters of PGER (total reflux time, clearance, number of episodes, number of episodes greater than 5 minutes duration and duration of longest episode) were significantly improved (p less than 0.01-0.05) post-operatively (as globally as by position supine and upright) and this improvement was associated with resolution of symptoms in 19 (95%) patients. Of the manometric parameters evaluated (lower esophageal sphincter pressure--LESP--and length--LESL, peristaltic, triphasic, biphasic, absent and simultaneous waves and relaxation of LES) surgery only produced improvement in the lower esophageal sphincter pressure (LESP) and length (LESL) (p less than 0.001). We conclude that antireflux surgery (Nissen) by improving the pressure and length of the LES is capable of producing clinical and ph-metric remission in almost all (95%) of patients studied six months after.

Age Factors↗
PubMed1985

Electrocardiographic findings in acute right ventricular infarction: sensitivity and specificity of electrocardiographic alterations in right precordial leads V4R, V3R, V1, V2, and V3.

To determine the sensitivity, specificity, predictive value and diagnostic efficiency of electrocardiographic alterations in the diagnosis of acute right ventricular infarction, 43 autopsy patients with acute myocardial infarction and an electrocardiogram including 12 leads plus leads V3R and V4R were studied. Group A included 21 patients with right ventricular infarction, of whom 14 (group AI) had posterior and 7 (group AII) had anterior right ventricular infarction. Group B included 22 patients without right ventricular infarction. Excluding group AII patients, the sensitivity of the presence of a Q wave reached 78.6% in lead V4R and decreased in leads V1 to V3; its specificity was low in all the leads. The sensitivity of ST segment elevation reached 100% in lead V4R and decreased in leads V1 to V3; its specificity was highest (68.2%) in leads V4R and V3R, its negative predictive value was 100% and its diagnostic efficiency was 80.6%. The criterion of ST segment elevation in lead V4R being higher than that in leads V1 to V3 was less sensitive (78.6%) than ST segment elevation in lead V4R alone, but its specificity reached 100%, its positive predictive value 100% and its diagnostic efficiency 91.7%. In conclusion, there are no electrocardiographic criteria to identify anterior right ventricular necrosis, but posterior right ventricular necrosis may be identified by the presence of a Q wave or ST segment elevation in the right precordial leads, reaching the highest sensitivity and specificity in lead V4R. The criterion of ST segment elevation in lead V4R being higher than that in leads V1 to V3 offers the highest specificity and efficiency in the diagnosis.

Acute Disease↗
PubMed1980

[Comparative study between HBsAg positive and HBsAg negative panarteritis nodosa in a series of 25 cases (author's transl)].

Clinical symptoms, biochemical analyses, immunologic status and angiographic findings corresponding to seven HBsAg positive patients with panarteritis nodosa and to 16 HBsAg negative patients with panarteritis nodosa have been compared. HBsAg positive cases showed a statistical significant higher incidences of Raynaud's phenomenon (p less than 0.05) and cardiopathies (p les than 0.05), as well as high occurrence of blood hypertension, artropathy, liver involvement and peripheral neuropathy. Significant differences in relation to cell immunity were not found. Humoral immune disturbances were more common among HBsAg positive patients, being hypergammaglobulinemia (p less than 0.01), IgM increase and decrease of complement factors (C3, C4 and C3PA) the most frequent abnormalities recorded. Angiographic studies revealed a high incidence of microaneurisms for the HBsAg positive group.

Adolescent↗