PubMed Health⌕ Search

Biomedical subjects

L García

Publications and source records attributed to L García.

At least 37 records · Page 2Linked to original sources
PubMed2002

The initial inositol 1,4,5-trisphosphate response induced by histamine is strongly amplified by Ca(2+) release from internal stores in smooth muscle.

We have studied the Ca(2+)-dependence and wortmannin-sensitivity of the initial inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) response induced by activation of either histamine or muscarinic receptors in smooth muscle from guinea pig urinary bladder. Activation of H(1) receptors with histamine (100 microM) produced a significant elevation in Ins(1,4,5)P(3) levels with only 5s stimulation and in the presence of external Ca(2+). However, this response was abolished fully by either the prolonged absence of external Ca(2+) or the depletion of internal Ca(2+) stores with thapsigargin (100nM) or ryanodine (10 microM). In contrast, the same conditions only slightly reduced the initial Ins(1,4,5)P(3) response induced by carbachol. The prolonged incubation of smooth muscle in 10 microM wortmannin to inhibit type III PI 4-kinase abolished both the early histamine-evoked Ins(1,4,5)P(3) and Ca(2+) responses. Conversely, wortmannin did not alter Ca(2+) release induced by carbachol, despite a partial reduction of its Ins(1,4,5)P(3) response. Collectively, these data indicate that the detectable histamine-induced increase in Ins(1,4,5)P(3) is more the consequence of Ca(2+) release from internal stores than a direct activation of phospholipase C by H(1) receptors. In addition, the effect of wortmannin implies the existence of a Ca(2+)-dependent amplification loop for the histamine-induced Ins(1,4,5)P(3) response in smooth muscle.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed2002

Experimental inoculation of conventional pigs with porcine reproductive and respiratory syndrome virus and porcine circovirus 2.

Postweaning multisystemic wasting syndrome (PMWS) is a disease of nursery and fattening pigs characterized by growth retardation, paleness of the skin, dyspnea, and increased mortality rates. Porcine circovirus 2 (PCV2) has been demonstrated to be the cause of PMWS. However, other factors are needed for full development of the syndrome, and porcine reproductive and respiratory syndrome virus (PRRSV) infection has been suggested to be one of them. Twenty-four conventional 5-week-old pigs were distributed in four groups: control (n = 5), PRRSV inoculated (n = 5), PCV2 inoculated (n = 7), and PRRSV and PCV2 inoculated (n = 7). The two groups inoculated with PRRSV showed growth retardation. Pigs inoculated with both PRRSV and PCV2 had increased rectal temperature. One of these pigs developed wasting, had severe respiratory distress, and died. The most important microscopic lesion in pigs inoculated with PCV2 was lymphocyte depletion with histiocytic infiltration of the lymphoid organs, more severe and in a wider range of tissues in doubly inoculated pigs. Interstitial pneumonia was observed in the three inoculated groups. PCV2 nucleic acid was found by in situ hybridization in larger amounts and in a wider range of lymphoid tissues in PRRSV- and PCV2-inoculated than in PCV2-inoculated pigs. TaqMan PCR was performed to quantify the PCV2 loads in serum during the experiment. PCV2 loads were higher in doubly inoculated pigs than in pigs inoculated with PCV2 alone. These findings indicate that severe disease can be reproduced in conventional 5-week-old pigs by inoculation of PRRSV and PCV2. Moreover, these results support the hypothesis that PRRSV infection enhances PCV2 replication.

Animals↗
PubMed2002

Treatment with the insulin analogue lispro in children and adolescents with type 1 diabetes mellitus: evaluation over a 3-year period.

The aim of the present study was to evaluate the degree of metabolic control obtained with the use of the insulin analogue lispro compared to the previous regimen with classical regular insulin in children and adolescents with Type 1 diabetes mellitus. HbA1c, lipid metabolism, body mass index (BMI), frequency of severe hypoglycaemia, carbohydrate intake, total daily insulin requirements and its distribution during the day were analysed in 44 diabetics patients (57% males and 43% females) throughout a 3-yr period. The mean age of the patients at the beginning of the study was 15.6 +/- 2.7 yr with a mean duration of the disease of 8.01 +/- 3.4 yr. All data were evaluated for the year before the change of treatment, and 1 yr (44 patients), 2 yr (19 patients) and 3 yr (13 patients) after the change. HbA1c levels did not significantly change (6.6 +/- 1.1% with regular insulin, 6.32 +/- 1.05% in the 1st year with lispro, 6.6 +/- 1.1% in the 2nd yr with lispro, 6.33 +/- 0.9% in the 3rd yr with lispro). However, significant differences (p = 0.03) were found after 3 yr of treatment in those patients who changed to insulin lispro therapy due to a bad glycaemic control. The total daily insulin dose (U/kg/d) remained unchanged. The total short-acting/intermediate-acting insulin ratio significantly decreased (45.9 +/- 0.1% regular insulin; 37.2 +/- 0.1% 1st yr lispro (p < 0.001); 33.6 +/- 0.1% 2nd yr lispro (p < 0.05); 35.5 +/- 0.1% 3rd yr lispro (p < 0.05). BMI and lipid profile remained unchanged. The self-reported daily carbohydrate in take significantly decreased due to a reduction of snacks. Total number of episodes of severe hypoglycaemia did not change significantly. In conclusion insulin lispro treatment did not modify the daily insulin dose, but reduced the short-acting/intermediate acting insulin ratio. The metabolic control remained unchanged. The number of patients reporting severe hypoglycaemia was similar despite the treatment schedule. After this 3-yr duration trial all patients decided to continue the treatment with lispro insulin.

Adolescent↗
PubMed2002

Malaria vectors in Bioko Island (Equatorial Guinea): PCR determination of the members of Anopheles gambiae Giles complex (Diptera: Culicidae) and pyrethroid knockdown resistance (kdr) in An. gambiae sensu stricto.

Anopheles gambiae sensu lato Giles, 1902 and Anophelesfunestus Giles, 1900 are the main malaria vectors on the island of Bioko (Equatorial Guinea). This study was carried out to determine: a) members of the An. gambiae complex that may be present on the island of Bioko and, b) the sensitivity of An. gambiae sensu stricto to pyrethroids. The analysis by PCR detected the presence of An. gambiae s.s. as the major vector of the complex and the "forest chromosomal form" was demonstrated by cytogenetic analysis. The presence of Anopheles melas in the southwest, north and southeast of the island justifies its study as a vector. The molecular characterization of pyrethroid knockdown resistance (kdr) showed that the populations of An. gambiae s.s. were sensitive and no mutations were found. This fact justifies the implementation on a large scale of pyrethroid-impregnated bednets within the framework of the Malaria Control Program of Equatorial Guinea.

Animals↗
PubMed2002

Hepatitis C virus phylogeny: a useful clinical tool.

In order to type 45 recent isolates of Hepatitis C virus (HCV) originating from four different geographic regions of the world, we performed phylogenetic analysis of a 192 nucleotides (nts) long sequence from the 5'non-coding region (5'-NCR) of the virus genome and compared them with 55 HCV isolates/strains of known type. The results of this study showed that phylogenetic studies can assign an HCV isolate to the correct type in 100% and to the correct subtype in 98%. A comparison ofthis method with other methods using commercial kits revealed that it is appropriate for clinical use and is cost effective.

Hepacivirus↗
PubMed2002

Restoration of peristalsis in the esophagus of a patient diagnosed of achalasia.

We report the case of a patient with dysphagia in whom a clinical and manometric follow-up was carried out. We initially observed a motor disorder of the esophageal spasm type. During manometric follow-up a progression to vigorous achalasia was observed. The patient was treated with pneumatic dilation, which obtained a good response to treatment. In manometries performed after treatment we observed a return of peristalsis in the distal esophageal body. Early treatment and short evolution of disease may allow peristalsis to recover in these cases. Peristalsis recovery casts new doubts on achalasia etiology.

Adult↗
PubMed2001

Panic disorder in a Spanish sample of 89 patients with pure alcohol dependence.

High rates of anxiety disorders, including panic disorder (PD), have been found in patients suffering from alcohol dependence (AD). It has been suggested that alcoholic subjects with PD represent a more severe subgroup of patients. Eighty-nine patients with 'pure' AD (without abuse of other drugs) were examined and compared for the presence of PD. Several clinical scales were administered to assess symptomatology and severity. Twenty-three patients (25.8%) met the criteria for PD. The mean age at onset for alcohol use was 18.7 versus 28.5 years for PD onset. Our finding of an earlier onset for alcoholism than for PD in a sample of Spanish patients illustrates the potential importance of transcultural factors. These patients were more likely to be women and to have first-degree relatives with PD. Overall, alcoholic patients with comorbid PD showed greater clinical severity. They were found to have more comorbidity with axis I disorders (major depression and dysthymia), greater clinical severity, and a history of more suicide attempts.

Adult↗
PubMed2001

Diversification of hepatitis C viruses in South America reveals a novel genetic lineage.

Hepatitis C virus (HCV) has high genomic variability and, since its discovery, at least six different types and an increasing number of sub-types have been reported. Genotype 1 is the most prevalent genotype found in South America. Recent phylogenetic analysis of strains isolated in Uruguay revealed the presence of a different genetic lineage from major sub-types 1a and 1b. In order to study if type 1 HCV strains circulating in the South American region can be associated with this genetic lineage, sequence data obtained from the 5' non-coding region from 6 type 1 patients from Chile, were compared with sequences obtained from 12 type 1 Uruguayan and 9 type 1 Brazilian patients as well as 17 different strains of all types isolated elsewhere. The phylogenetic analysis revealed the existence of type 1 strains of this novel genetic lineage in all South American countries studied, and indicates a diversification of HCV viruses in the South American region.

5' Untranslated Regions↗
PubMed2001

Study of Ligmed-A, an antidiarrheal drug based on lignin, on rat small intestine enzyme activity and morphometry.

This study aimed to determine the potential toxic effect of 4-day oral treatment with a lignin-based formulation on the enzymatic activity and morphology of the small intestine of rat. Ligmed-A is collected from sugarcane and is used to treat diarrhea in weaning pigs. The compound is about 90% lignin, an insoluble polyphenolic constituent of plants and a component of dietary fiber. The duodenal, jejunal and ileal mucosa of control rats and those receiving 2 g/kg Ligmed-A showed similar protein contents of about 100 mg/g. The sucrase and alkaline phosphatase activities of the three intestinal segments were unaltered after administration of the compound. Nonhistological alterations were observed after treatment. Our results, together with those of previous studies which found no toxicological effects, indicate that Ligmed-A could provide a potent antidiarrheal treatment in the veterinary area. However, further studies are required to examine its use in humans.

Administration, Oral↗
PubMed2001

Sedation for gastrointestinal endoscopy. Analysis of tolerance and complications.

OBJECTIVE: To analyse tolerance and complications in patients undergoing a gastrointestinal endoscopy. PATIENTS AND METHODS: One hundred forty three patients were prospectively studied: 44.8% underwent a diagnostic upper endoscopy; 13.3%, a therapeutic upper endoscopy; 37%, a diagnostic colonoscopy and 4.9%, a therapeutic colonoscopy. Midazolam or midazolam combined with meperidine were used. Tolerance, level of sedation and complications were studied. Chis quare and ratio comparison tests were used for the statistical analysis. P-values less than 0.05 were considered as statistically significant. RESULTS: In the diagnostic upper endoscopy group, tolerance was better with midazolam plus meperidine vs midazolam only (83.8% and 59.3% respectively); p < 0.05. In the therapeutic upper endoscopy group, tolerance was also better when both drugs were combined; p < 0.05. In the diagnostic and therapeutic colonoscopy groups, tolerance was good in 63.5% and 85.7% of patients, respectively. Men had better tolerance for upper endoscopy; p < 0.05. Tolerance was worse in patients under 40 years of age for upper endoscopy; p < 0.05. Mild desaturation occur in 27.3% of patients, being more severe in therapeutic procedures; p < 0.05. CONCLUSIONS: Tolerance was good in a high percentage of patients, and better in men and in patients older than 40 years of age. The main problem is desaturation, that increases in therapeutic procedures.

Adolescent↗
PubMed2001

[Effects of estrogens and progestogens on the lipid profile in postmenopausal hypogonadism].

It is known that postmenopausal hypogonadism is associated to an increase of low density lipoproteins (LDL) and a decrease of high density lipoproteins (HDL) that increases the risk of cardiovascular disease. The hormonal replacement therapy of estrogen with or without a progestin reduces such risk in approximately 50%. This study of a retrospective clinical design was longitudinal, descriptive and comparative of 172 patient grouped for treatment received: a) with estrogen and progestin (E + P: 59.1%, n = 122), and b) estrogen alone (E: 40.9%, n = 50), in whom was determined: lipid profile and aterogenic risk initially and each year until 5 years of follow up. Results obtained were: 172 with average age of 51.5 +/- SD 9.2 years with average 5.5 duration years of postmenopause, in both groups the aterogenic risk was reduced as well as concentrations of serum LDL, while HDL increased. It is concluded that hormonal replacement therapy exerted a substantial effect upon main lipoproteins (HDL, LDL) modifying sensitively the aterogenic risk and consequently ameliorating the risk of cardiovascular disease and atherosclerosis.

Arteriosclerosis↗
PubMed2000

Passive protection of serum from volunteers inoculated with attenuated strain 638 of Vibrio cholerae O1 in animal models.

As part of the studies to obtain an oral vaccine against cholera disease, the protective effect of serum from volunteers inoculated in a controlled trial with a candidate live attenuated vaccine of Vibrio cholerae O1, El Tor Ogawa (638; CTX&phi; mutant, hap::celA), was tested. It was confirmed that the serum, as well as the purified IgG and IgA from the volunteers had a protective effect in both of the animal models used, although the purified antibodies needed the presence of complement to be protective. These results emphasize the expectations about the protective potential of the candidate in challenge studies in humans to be conducted very soon.

Animals↗
PubMed2000

[Relationship between iron stores and diabetes mellitus in patients infected by hepatitis C virus: a case-control study].

BACKGROUND: To investigate whether the high prevalence of diabetes observed in patients infected by the hepatitis C virus (HCV) is associated to iron stores. PATIENTS AND METHODS: Serum ferritin levels were determined in 123 patients infected by HCV (55 diabetic and 68 non-diabetic). RESULTS: Serum ferritin concentrations were higher in diabetic than in non-diabetic patients (205 ng/ml [14-861] vs. 58 ng/ml [15-494]; p < 0.0001). CONCLUSIONS: Serum ferritin levels are related with the presence of diabetes in patients infected by HCV.

Biopsy↗
PubMed2000

Modeling cyclooxygenase inhibition. Implication of active site hydration on the selectivity of ketoprofen analogues.

Molecular modeling studies performed on the two cyclooxygenase isozymes (COXs) suggest that active site hydration is crucial for understanding inhibitor selectivity. In this work, models have been constructed considering some implicit water molecules, placed in the position suggested by GRID, that participate in the dynamic hydrogen-bonding network at the polar active site entrance together with protein residues 355, 524, 120, and 513. The selectivity observed for ketoprofen (1) and the structural analogues 2 and 3 may be rationalized in terms of such implicit hydration.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

The quantitive chlorioallantoic membrane test using trypan blue stain to predict the eye irritancy of liquid scintillation cocktails.

The chorioallantoic membrane-trypan blue staining assay (CAM-TBS) is used to evaluate the potential ocular irritation caused by liquid scintillation cocktails constituted by complex mixtures, including surfactants and other potential irritants. The harmful effect of these substances is determined by the amount of trypan blue adsorbed by the CAM. In the membrane previously treated with the scintillation liquids this amount was concentration dependent only in certain cases, irrespective of the water solubility of the mixtures. In general, it showed a high correlation (r=0.986) with the scores obtained in the Draize eye irritation test. In the present study, only two cocktails presented values of trypan blue adsorption higher than those recorded for their eye irritation in vivo, irrespective of the solvent nature. Unlike the classical HET-CAM procedure, this assay is objective and allows the evaluation of opaque and coloured substances without interfering in the determination of irritancy. Despite these advantages, the method is not suitable for complex mixtures of products that induce ocular irritation in small quantities.

Allantois↗
PubMed2000

What predictive parameters best indicate the need for emergent gastrointestinal endoscopy after foreign body ingestion?

Our aim was to determine what parameters may be used to indicate an emergent endoscopy after foreign body (FB) ingestion and to ascertain how often FBs are found endoscopically. Demographic data, gastroesophageal antecedents, clinical and endoscopic data, and complications were obtained. We examined 122 patients endoscopically. The onset of symptoms was immediate after FB ingestion in 93% of patients. Dysphagia was the most frequent symptom (66%), with the pharynx the most frequent location of impaction (71%). Endoscopy confirmed the presence of FBs in 52% of patients. Extraction was performed in 78%. The immediate onset of symptoms, dysphagia, and the absence of pharynx localization of impaction were predictive indicators of a positive FB finding (p < 0.05), with diagnostic sensitivity of 86% and specificity of 63%. Upper endoscopy should be performed in all patients with FB ingestion, even though no FB was found in 48%.

Deglutition Disorders↗