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T Alarcón

Publications and source records attributed to T Alarcón.

At least 73 records · Page 4Linked to original sources
PubMed1998

[Use of the polymerase chain reaction (PCR) for the diagnosis of Helicobacter pylori infection in pediatric patients].

BACKGROUND: Several direct or non direct methods may be used to detect H. pylori infection. A molecular method, PCR with ureA primers, was used in this study in 43 gastric biopsies obtained from paediatric patients with digestive symptomatology and the results were compared with those obtained by histology and culture. METHODS: Culture and histological stain were performed from gastric biopsies taken at routine endoscopy following standard methodology. A PCR with specific primers for the ureA gene was applied and the 411 pb fragment detected by agarose gel electrophoresis. RESULTS: From the 43 gastric biopsies, 21 were positive by culture (48.8%), 25 by histology (58.1%) and 29 by PCR (67.4%). In 30 biopsies (69.7%) PCR results were in good agreement with the reference method (histology and/or culture). In 7 biopsies the PCR was positive (16.3%), although the reference method was negative and in 6 (13.9%) the PCR was negative being positive the histology (5 samples) or histology and culture (1 sample). CONCLUSIONS: PCR shows the highest positive percentage among the methods used. The use of as many methods as possible in the H. pylori infection, increases the diagnosis of the infection.

Adolescent↗
PubMed1997

Ketanserin and anxiety levels: influence of gender, estrous cycle, ovariectomy and ovarian hormones in female rats.

The influence of gender, estrous cycle, ovariectomy and ovarian hormones on the behavioral effects of the 5-HT2 receptor antagonist, ketanserin (KET), was studied. Intact males, female rats in the four stages of the estrous cycle and ovariectomized (OVX) female rats 14 days after surgery were used. The OVX rats received progesterone [PROG, 25 mg/kg, subcutaneously (SC)] and/or estradiol benzoate (EB, 10 micrograms/kg, SC). KET (3 mg/kg, SC) was injected 30 min before testing. All the animals were subjected to the following behavioral tests: exploration of an elevated plus-maze and retention of a passive-avoidance response. KET enhanced the exploration of the open arms in diestrous female rats but inhibited this behavior during the other stages of the cycle and in OVX rats injected either with oil or EB. This dose of KET was ineffective in males and in OVX rats injected with PROG. Furthermore, KET inhibited the retention of the passive avoidance response in males, in diestrous and metestrous female rats and in OVX rats injected with oil. In estrous females and in OVX rats injected with EB, KET enhanced the passive-avoidance response. These results demonstrate that the sensitivity to KET differs with the gender, estrous cycle and hormonal treatment and suggest that central serotonergic activity is influenced by the hormonal status of the animal.

Animals↗
PubMed1996

In vitro activity of omeprazole in combination with several antimicrobial agents against clinical isolates of Helicobacter pylori.

An agar dilution checkerboard method was used to evaluate the in vitro activity of omeprazole combined with clarithromycin, amoxicillin, and ceftibuten, respectively, against clinical isolates of Helicobacter pylori. Mueller-Hinton agar plus 5% horse blood, an inoculum of 10(6) cfu/ml, and incubation of 72 h in a CO2 atmosphere were used. With the omeprazole and clarithromycin combination, synergism was observed in 51.5% and partial synergism in 39.3% of 33 strains; with omeprazole and amoxicillin, synergism was observed in 3% and partial synergism in 60.6% of 33 strains; and with omeprazole and ceftibuten, synergism was observed in 33.3% and partial synergism in 50% of 24 strains. Antagonism between omeprazole and each antibiotic was exhibited in 0%, 6.1%, and 4.1% of these groups of strains, respectively. Of the antibiotic combinations tested, omeprazole plus clarithromycin exhibited synergism (partial or total) in the highest percentage of strains.

Amoxicillin↗
PubMed1996

Emergence of resistant isolates of Acinetobacter calcoaceticus- A. baumannii complex in a Spanish hospital over a five-year period.

Acinetobacter calcoaceticus-A. baumannii complex species have emerged as a relevant cause of nosocomial infection and colonization over the past 20 years, mainly in intensive care units. The aim of this study was to investigate the in vitro activity of 14 antimicrobial agents against 177 clinical isolates from patients admitted to a Spanish teaching hospital over a five-year period. Susceptibility rates or 99%, 99%, and 74% were obtained for imipenem, meropenem, ampicillin plus sulbactam, and amikacin, respectively. Increases in resistance were detected mainly for ticarcillin, piperacillin plus tazobactam, ceftazidime, amikacin, and ofloxacin. These results indicate that treatment of nosocomial infections due to Acinetobacter calcoaceticus-A. baumannii complex strains may be difficult.

Acinetobacter calcoaceticus↗
PubMed1995

[Wilson's disease: a review apropos of a clinical experience in 16 patients].

Wilson's Disease is an inherited disorder of copper metabolism. We report 16 patients (6 males) with the disease; 6 had hepatic involvement exclusively, 4 had neurological involvement, 3 had a neurological and hepatic involvement and 3 were asymptomatic. The age onset was 9 years for hepatic and 17 years for neurologic involvement. The mean delay in diagnosis was 14 months. Chronic hepatitis, cirrhosis and fulminant hepatic failure were the clinical forms of liver disease. Patients with neurologic disorders had behavioral disturbances and extrapyramidal manifestations such as dystonia and parkinsonism. Patients had a good response to penicillamine, except 3 that died of liver complications, in whom the treatment was delayed or discontinued. We conclude that this metabolic disease must be suspected in pubertal children and in adults of less than 30 years old with liver disease of unknown origin or behavioral alterations associated to an extrapyramidal syndrome.

Adolescent↗
PubMed1994

Nosocomial septicemia caused by Serratia plymuthica.

We report a case of nosocomial septicemia in a 79-year-old patient caused by Serratia plymuthica with no evident focus of infection. The patient was treated with gentamicin (40 mg every 8 h) during 10 days; clinical resolution of the infection was obtained after the 10-day treatment period.

Aged↗
PubMed1993

High-level quinolone resistance amongst clinical isolates of Escherichia coli and Klebsiella pneumoniae from Spain.

A recombinant plasmid containing gyr A encoding wild-type Escherichia coli quinolone susceptible DNA gyrase A subunits has been used as a broad host range gene probe. Strains expressing gyr A-mediated quinolone resistance become susceptible to quinolones upon insertion of the plasmid, whereas the plasmid without gyrA (pLA2917, vector) has no effect. Fifteen highly ciprofloxacin-resistant E. coli and three Klebsiella pneumoniae (MICs 2-64 mg/L) were isolated from clinical specimens in the Hospital de la Princesa, Madrid, Spain. Plasmid pNJR3-2 and pLA2917 were introduced into the clinical isolates by conjugation, and transconjugants selected with tetracycline or kanamycin (for which the plasmids encode resistance). Ten transconjugants from each mating, the original isolates, the gene probe and vector control were screened for susceptibility to nalidixic acid, ciprofloxacin, ofloxacin, norfloxacin, tetracycline, chloramphenicol, cefoxitin and trimethoprim. Lower MICs of quinolones were seen for the transconjugants of two K. pneumoniae isolates in the presence of the gene probe, suggesting that these isolates harboured mutations in gyr A. Plasmid profiles confirmed the presence of the probe. The susceptibility of the third K. pneumoniae strain and all E. coli isolates were unaffected by insertion of the plasmid, suggesting another mechanism was responsible for quinolone resistance.

4-Quinolones↗
PubMed1993

[Follow-up of the quantitative serological response to the treatment of Helicobacter pylori infection in children].

BACKGROUND: The aim of the present study was to know the usefulness of a enzyme immunoanalysis (EIA) technique for the monitorization of the serologic to treatment of infection by Helicobacter pylori in Spanish children. METHODS: 17 children with digestive symptomatology in whom the diagnosis of infection by Helicobacter pylori was confirmed and eradication was objectified following a month of treatment with amoxycillin, metronidazole and Bismuth subcitrate were studied. In each patient a biopsy of the gastric mucosa was performed and a sample of serum was withdrawn for initial diagnosis and for control of eradication once treatment had finished (mean time between diagnosis and confirmation of eradication was 79.6 +/- 33.5 days). The samples of gastric mucosa were processed by standard methodology (histologic and/or culture). Serologic determinations (IgG and IgA) were carried out using a EIA technique (Pyloriset EIA-G and EIA-A; Orion Diagnostica). RESULTS: In 12 of the 17 patients resolution of the clinical symptomatology was produced. A decrease in the levels of IgG was observed in 15 (88.2%) and of IgA in 14 (82.3%) of all the children studied. A significant difference was found between the mean values of the levels of IgG (p < 0.01) and IgA (p < 0.05) in the 17 patients at the time of diagnosis and following eradication. CONCLUSIONS: In agreement with the present results the series study of the quantitative level of antibodies IgG and IgA versus Helicobacter pylori is shown as an adequate instrument for evaluating the response to treatment in pediatric patients.

Adolescent↗
PubMed1990

Isolation of fluoroquinolone-resistant Escherichia coli and Klebsiella pneumoniae from an infected Hickman catheter.

Escherichia coli and Klebsiella pneumoniae resistant to fluoroquinolones were isolated from an infected Hickman catheter in a 43-year-old diabetic patient who had previously been treated with a 24-day course of ciprofloxacin (200 mg/12 h i.v.). MICs and MBCs of nalidixic acid, norfloxacin, ciprofloxacin, ofloxacin, pefloxacin and fleroxacin were determined for the strains using the methodology recommended by the NCCLS. Both strains were resistant to all the quinolones tested. Since long-term treatment with quinolones might favour the emergence of quinolone resistance or colonization with quinolone-resistant organisms, it is important to monitor for the development of bacterial resistance during therapy with the new fluoroquinolones.

Adult↗
PubMed1989

[One hour xylose test blood in the diagnosis of celiac disease].

Plasma levels of d-xylose one hr after a standard 5 g oral dose were measured in 82 children suspected of having celiac disease. Duodenal mucosa was obtained by intestinal biopsy in all. Among patients with normal mucosa, 95% had xylose levels above 20 mg/dl; 100% of patients with a flat mucosa had levels under 20 mg/dl. Results were independent of patients age. We conclude that this is a reliable test to screen patients suspected of having celiac disease, prior to intestinal biopsy.

Adolescent↗
PubMedDate not supplied

Towards whole-organ modelling of tumour growth.

Multiscale approaches to modelling biological phenomena are growing rapidly. We present here some recent results on the formulation of a theoretical framework which can be developed into a fully integrative model for cancer growth. The model takes account of vascular adaptation and cell-cycle dynamics. We explore the effects of spatial inhomogeneity induced by the blood flow through the vascular network and of the possible effects of p27 on the cell cycle. We show how the model may be used to investigate the efficiency of drug-delivery protocols.

Adaptation, Physiological↗
PubMedDate not supplied

[The Helicobacter pylori adhesion gene: relation with the origin of the isolates and associated disease].

BACKGROUND: The adhesion gene (hpaA) of Helicobacter pylori isolates from different Spanish regions was studied by PCR-RFLP in order to group the strains according to the origin of the strains and to relate it with ulcer or gastritis production. METHODS: One hundred and forty three Helicobacter pylori clinical isolates were obtained from the culture of gastric biopsies (29 from Ibiza, 39 from Madrid, 36 from Almería and 39 from Avilés). After DNA extraction, a PCR was performed to amplify a 375 pb fragment of the hpaA gene which was digested with Hinfi and SauIIIa. RESULTS: The gene was detected in all of the strains studied. After digestion with Hinfi and SauIIIa, three and four patterns called 1, 2 and 3 and A, B, C and D were obtained, respectively. Strains from Madrid and Almería showed the highest hpaA genetic variability. In the relationship with the pathology, patterns 1 and A were the most prevalent in strains obtained from patients with ulcer and with gastritis. CONCLUSIONS: The results of hpaA gene study show the genetic variability of Helicobacter pylori and slight differences according to the origin were found.

Adhesins, Bacterial↗
PubMedDate not supplied

[Evaluation of a western blot technique (Helicoblot 2.0) fpr the detection of specific Heliocobacter pylori antigens in children)].

BACKGROUND: The aim of this study was to evaluate the diagnosis usefulness of antibodies detection against different specific antigens of H. pylori (Hp) in children by a Western-blot commercially available (Helicoblot 2.0). MATERIAL AND METHODS: 96 symptomatic paediatric patients in two groups were studied. Group 1: 48 patients Hp positive by culture and/or histology (mean age, 10.19 +/- 3.40 years; 27 boys and 21 girls) and group 2: 48 patients Hp negative by both culture and histology (mean age, 9.31 +/- 3.15 years; 34 boys and 14 girls). Qualitative IgG detection against the protein antigens of 19.5 kD (urease E), 26.5 kD (urease D), 30 kD (urease H), 35 kD, 89 kD (vacuolating toxin VacA) and 116 kD (cagA protein) was determined by a Western-blot assay (Helicoblot 2.0, Genelabs, Singapore). RESULTS: A specificity of 100% was obtained when reactivity against 19.5 kD protein (urease E) was considered alone. However, the best accuracy levels were observed with 26.5 kD (urease A) and 30 kD (urease H) antigens. An accuracy of 88.5% was observed when the manufacturer's recommended criteria was used (positivity of at least 116, 89 or 35 kD single bands or positivity of at least 2 bands of the 30, 26.5 or 19.5 kD). CONCLUSIONS: Helicoblot 2.0 is a good method to diagnosis Hp infection in children. A criteria combining IgG against 2 urease antigens (preferentially urease A) or one urease antigen and a virulence associated protein (CagA o VacA) is recommended.

Adult↗