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C Calvo

Publications and source records attributed to C Calvo.

At least 55 records · Page 3Linked to original sources
PubMed1997

Comparison of MB-check and Löwenstein-Jensen media for recovery of mycobacteria.

We have compared the rate of recovery of mycobacteria with the MB-Check culture system (liquid phase) and the Löwenstein-Jensen (LJ) medium in 2,907 clinical specimens obtained from 830 patients submitted for mycobacterial culture during 1-year period. Direct smear examination was carried out by auramine-rhodamine staining. All primary isolates from the culture media were confirmed by Ziehl-Neelsen staining and identified by acridinium-ester-labeled DNA probes specific for Mycobaterium tuberculosis complex. A total of 214 isolates were of the M. tuberculosis complex (88 patients) and 54 of "potentially pathogenic environmental mycobacteria" (45 patients). A total of 117 (54.7%) samples were smear-positive and the remaining 97 (45.3%) were smear-negative. There was a significant difference in the percentage of positive cultures obtained by the MB-Check method (99.1%) as compared with the LJ medium (73.8%) (P < 0.05). This difference, however, occurred almost exclusively at the expense of the 97 smear-negative samples (positive cultures 97.95% by the MB-Check method vs. 42.3% by the LJ culture, P < 0.05). The number of patients diagnosed of tuberculosis by the MB-Check was significantly higher as compared with LJ medium (88 [100%] vs. 77 [87.5%], P < 0.05). In 11 (12.5%) patients, the diagnosis was only established by the MB-Check system. In smear-positive samples, the mean (+/-SD) detection time for M. tuberculosis complex was 14.8 +/- 8 days with MB-Check and 19.9 +/- 7 days with LJ medium. The corresponding figures in smear-negative samples were 22.8 +/- 3 days and 27.8 +/- 6 days, respectively. DNA probes directly applied to MB-Check liquid medium showed a sensitivity of 98.8% and specificity of 100%. These results indicate that the MB-Check system is more efficient for the recovery of mycobacteria than LJ medium.

Bacterial Typing Techniques↗
PubMed1997

Usefulness of gastric intramucosal pH for monitoring hemodynamic complications in critically ill children.

OBJECTIVE: To assess the efficacy of gastric intramucosal pH for the evaluation of tissue perfusion and prediction of hemodynamic complications in critically ill children. DESIGN: Open prospective study without controls. SETTING: Pediatric intensive care unit (ICU) of a tertiary care university pediatric hospital. PATIENTS: Thirty critically ill children (16 boys and 14 girls), age range: 3 months-12 years. MEASUREMENTS AND RESULTS: A tonometry catheter was placed in the stomach of all patients on admission to the pediatric ICU. Simultaneous tonometry and arterial gas measurements were made on admittance and every 6-12 h throughout the study; a total of 202 measurements were made. The catheter was removed after extubation and/or when the patient was hemodynamically stable. Intramucosal pH was calculated using the Henderson-Hasselbalch equation based on the pCO2 of the tonometer and arterial bicarbonate. Intramucosal pH values between 7.30 and 7.45 were considered to be normal. The patient's condition was analyzed using the Pediatric Risk Mortality Score (PRISM). The relations between intramucosal pH and the presence of major hemodynamic complications (cardiopulmonary arrest, shock), minor hemodynamic complications (hypotension, hypovolemia or arrhythmia), death, PRISM score and the duration of the stay in the pediatric ICU were analyzed. Intramucosal pH on admission was 7.48 +/- 0.15 on average (range 7.04-7.68). Five patients (16%) had an intramucosal pH lower than 7.30 on admission; these patients did not have a higher incidence of hemodynamic complications. The 16 patients (53%) who had an intramucosal pH of less than 7.30 at some time during the course of their disease had more hemodynamic complications than the patients who did not have pH lower than 7.30 (p < 0.0001). Every case of cardiopulmonary arrest and shock was related to intramucosal pH of less than 7.30. Patients with major complications (cardiopulmonary arrest and shock) had lower intramucosal pHs than those with minor hemodynamic complications (p = 0.03); similarly, they had low intramucosal pH readings more often than those with minor complications (p = 0.0032). Intramucosal pH values less than 7.30 had a sensitivity of 90% and a specificity of 98% as a predictor of hemodynamic complications. There was no relation between intramucosal pH lower than 7.30 and either PRISM or the duration of the stay in the pediatric ICU. Patients with intramucosal pH less than 7.20 had a higher PRISM than the patients who did not have pH lower than 7.20 (p < 0.05). A patient who died during the study due to cardiopulmonary arrest had prior intramucosal pH measurements of 7.23 and 7.10, and three patients died of late complications after the end of the study. Hemodynamic complications were not detected with arterial pH. Gap pH (arterial pH-intramucosal pH) and standard pH measurements yielded the same results as gastric intramucosal pH. CONCLUSION: Intramucosal pH could provide a useful early indication of hemodynamic complications in critically ill children.

Acid-Base Equilibrium↗
PubMed1997

The immunosenescent phenotype in mice and humans can be defined by alterations in the natural immunity reversal by immunomodulation with oral AM3.

The reactivities of monocyte/macrophages and natural killer (NK) cells (natural immunity) were evaluated following the administration of the biological response modifier AM3. The lower number of macrophages and NK cells in middle-aged mice (MAM) compared to young adult mice (YAM) were significantly elevated following AM3 treatment to equal or greater than YAM values. Both macrophage and NK cell cytotoxicity peaked at two days following AM3 treatment and remained elevated over control values for up to 8 days following a four days treatment regimen by the oral route. Of particular interest was the clinical effect of AM3 treatment in chronic bronchitis (CB) patients and various aged volunteers. In middle-aged patients with chronic bronchitis (MACBpts) AM3 treatment resulted in significant increases in the number of monocytes as well as their phagocytic and chemotactic activity. Differential NK cell cytotoxicities were observed in MACBpts compared to middle-aged healthy adults (MAHA) and young healthy adults (YHA). Cytotoxicity in YHA was 2-fold higher than MAHA and 5-fold higher than MACBpts. The depressed number of NK cells in MACBpts was reversed following the AM3 treatment to near NK cell levels in YHA. These observations help to explain how AM3 aids in the restoration of natural cellular immunity and its possible application as an adjuvant to bacterial & viral vaccines as well as in the treatment CB.

Adjuvants, Immunologic↗
PubMed1997

A monoclonal antibody-based enzyme immunoassay for the measurement of native and glycated apolipoprotein B-containing particles.

We describe the development of sandwich enzyme-linked immunosorbent assays designed to measure native and glycated apolipoprotein B containing particles in plasma. The assays utilize monoclonal antibodies anti native or glycated apo B-LDL for coating and a polyclonal anti apoB-LDL-peroxidase conjugate as the detecting antibody. The method is specific, sensitive and precise. The intra assay coefficient of variation for the plasma native and glycated apolipoprotein B-containing particles was determine to be 7.8% and 7.5%, respectively. The method described can provide specific and reproducible determinations of apoB and glycated-apoB containing particles in plasma; it will be of great interest in the evaluation of atherosclerotic risk in dyslipoproteinemic states in diabetic and non-diabetic subjects.

Antibodies, Monoclonal↗
PubMed1997

[Non-enzymatic glycosylation of lipoproteins in the pathogenesis of atherosclerosis in diabetics].

A significant factor associated with hiperglycaemia in diabetes is the resultant post-translational non-enzymatic glycation of plasma and cellular proteins. This process occurs in vivo by direct chemical reaction of glucose with protein alpha and epsilon amino groups. Because of the diverse evidences for direct involvement of non-enzymatic glycation of lipoproteins in the accelerated development of atherosclerosis in diabetic patients, most attention has been focused on the pathological properties of glycated lipoproteins. Glycation of LDL was found significantly increased in diabetic patients compared with normal subjects, even in the presence of good glycemic control. Metabolic abnormalities associated with glycation of LDL include diminished recognition of LDL by the classical LDL-receptor, and enhancement uptake of LDL by a low-affinity, high capacity receptor pathway on macrophages, thus stimulating foam cell formation, an early feature of atherosclerosis. Moreover, glycated LDL are more susceptible to oxidative modification than non-glycated LDL and glycation of LDL may alter their structure sufficiently to render them immunogenic. Being immunogenic, glycated-LDL accumulates in plasma and may enhance cholesterol ester accumulation in macrophages. Non-enzymatic glycation of HDL impairs its recognition by cells and induce a diminished efflux of cholesterol from cell membranes to HDL particles. Furthermore, glycated apolipoprotein A-1 isolated from plasma of diabetic subjects was deficient in activating lecithin: cholesterol acyl transferase, the driving force in reverse cholesterol transport, pathway responsible of the antiatherogenic properties of HDL.

Arteriosclerosis↗
PubMed1997

HLA-DQA1*0501 and DQB1*02 homozygosity and disease susceptibility in Spanish coeliac patients.

Coeliac disease (CD) susceptibility is strongly associated with HLA-DQA1*0501 and DQB1*02 alleles. There are discordant reports on whether homozygosity increases the risk. We genotyped HLA-DQA1*0501 and DQB1*02 in 50 CD patients, 100 parents, and 50 controls. Most patients (96%) were positive for DQA1*0501 (RR = 18.07, p < 0.001), 94% for DQB1*02 (RR = 17.55, p < 0.001), and 92% for both alleles together (RR = 31.82, p < 0.001). DQA1*0501 was found in 52% of controls, DQB1*02 in 44%, and only 24% had both alleles. Patients homozygosity or heterozygosity was estimated by assessing-in each case-whether one or both parents were carriers of the allele of risk. The frequencies of parents both positive for DQA1*0501 (58%) and for DQB1*02 (53.1%) were higher than expected by the fact that the proband is a carrier. These findings suggest that the frequency of homozygosity is increased among CD patients, and therefore, homozygosity for either DQA1*0501 or DQB1*02 represents a risk factor added to the fact of being a carrier.

Alleles↗
PubMed1997

[Multicenter prospective study on severe bacterial meningitis in children].

UNLABELLED: We prospectively studied the epidemiologic, clinic signs and outcome of bacterial meningitis in 125 children who were admitted into a PICU (Pediatric Intensive Care Unit) of 11 hospitals of Spain and whose meningitis was diagnosed between May 1994 and April 1995. RESULTS: The median age of the children was 3.55 +/- 3.32 years (range 1 month to 16.5 yrs). Eighty-eight were bacterial meningitis, probably bacterial 30 and aseptic 7. The most frequently isolated organisms were N. meningitidis (52), H. influenza type b (17) and S. pneumoniae (8). Twenty-five percent of N. meningitidis had C serotype. Incidence rate of each germen was depending of age. All patients diagnosed of H. influenza type b meningitis were less than 3 years old. H. influenza type b and meningococcus had similar incidence rate during the first year of life (27% versus 31%). During the first three years of life H. influenza type b produced one third of bacterial meningitis. A mortality rate of 5.6% (seven patients: 3 S. pneumoniae, 1 N. meningitidis, 1 H. influenza type b and 2 unknown germen) was observed. Patients who die had lower Glasgow coma score (p = 0.034) and seizures (p = 0.001) at admission. At discharge of PICU, 9 survivors (7.2%) had sequelae: mental retardation in 7 patients and hearing loss in two. One third of patients needed hemodynamic support and a 15% of them ventilatory support. CONCLUSIONS: Age is an important epidemiological factor in the etiology of pediatric acute meningitis. H. influenza type b and N. meningitidis had similar incidence rate during the first year of life. S. pneumoniae had the highest mortality rate (37.5%). The presence of coma and seizures at admission were associated with mortality.

Child, Preschool↗
PubMed1996

[Effect of nutritional conditions on the viscosity and emulsifying capacity of V2-7 biopolymer from Volcaniella eurihalina].

Volcaniella eurihalina is a moderately halophilic bacterium able to produce an exopolysaccharide (EPS) under different culture conditions. Rheological behavior of 1% EPS solutions varied depending on the conditions under which EPS were produced. The maximum viscosity was reached when maltose was used as carbon source. Limitations of phosphorus and sulfur also increased its viscosity power. On the other hand, the addition of residual oil products to the culture medium enhanced the production of this biosurfactant polymer.

Excipients↗
PubMed1996

[Lipoprotein in children and adolescents: relationship with family history of coronary artery disease].

BACKGROUND: Lipoprotein (a) is considered an independent cardiovascular risk factor. AIM: To study lipoprotein (a) levels in children of 18 years old or less with or without family history of coronary artery disease. SUBJECTS AND METHODS: Forty four children aged between 3 and 18 years old with a family history of coronary artery disease and 44 age and sex matched controls were studied. A fasting blood sample was obtained to measure total, HDL and LDL cholesterol, triglycerides, A1 and B apoproteins and lipoprotein (a). RESULTS: Compared to controls, children with a family history of coronary disease had higher total cholesterol (177 +/- 35 and 159 +/- 23 mg/dl respectively), LDL cholesterol (112 +/- 34 and 94 +/- 21 mg/dl respectively), triglycerides (89 +/- 38 and 71 +/- 25 mg/dl respectively), apoprotein B (85 +/- 17 and 65 +/- 13 mg/dl respectively) and lipoprotein (a) (40 +/- 50 and 22 +/- 31 mg/dl respectively). Thirty two percent of children with positive family history had lipoprotein (a) levels over 30 mg/dl, compared to 23% of controls. CONCLUSIONS: Children with family history of coronary artery disease have higher levels of cholesterol, triglycerides and lipoprotein (a) than matched controls.

Adolescent↗
PubMed1995

Clinical acceptability of ACE inhibitor therapy in mild to moderate hypertension, a comparison between perindopril and enalapril.

The aim of this 3-month double-blind study was to assess the antihypertensive effect and acceptability of perindopril in comparison with enalapril in patients with mild to moderate essential hypertension. After a 4-week placebo run-in period, 161 patients with supine diastolic blood pressure (DBP) between 95 and 115 mmHg were randomized to receive perindopril 4 mg or enalapril 10 mg once daily. If supine DBP was higher than 90 mmHg, treatment was adjusted monthly, first by doubling the dose and then by addition of hydrochlorothiazide 12.5 mg. After 3 months of active treatment the decrease in supine and standing blood pressures was statistically significant within both groups but was not statistically different between groups. The percentage of patients (65%) who achieved supine DBP of < or = 90 mmHg in the perindopril group was not significantly different from the enalapril group (73%). Monotherapy resulted in control of supine DBP in 56% of the perindopril group and 58% of the enalapril group; the addition of hydrochlorothiazide resulted in control of supine DBP in 6% and 15% respectively. The number of withdrawals for adverse events was statistically significant between groups (0 in the perindopril group and 7 in the enalapril group, p = 0.01). During active treatment the most frequently reported complaints were headaches and cough; there was not statistically difference between groups. Changes in laboratory parameters were minor and not significantly different between the two groups except for serum glucose, potassium, and triglyceride levels. In conclusion, there was no significance between perindopril and enalapril in terms of efficacy. Clinical acceptability seems to be better in the perindopril group.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1995

Development of monoclonal antibodies for the selective isolation of human plasma apolipoprotein A-containing particles.

Monoclonal antibodies (MAbs) to human plasma apolipoprotein A-I (apo A-I), denoted FF9 and 6B9, and apolipoprotein A-II (apo A-II), 3F5, were developed to be used in an immunoaffinity chromatography procedure to isolate lipoprotein particles Lp A-I and Lp A-I:A-II. MAb FF9 and MAb 6B9 reacted with apo A-I and high-density lipoprotein (HDL) while MAb 3F5 was directed to apo A-II and HDL. The apparent affinity constant (Kapp) for apo A-I of the MAb FF9 was higher (2 x 10(7) M-1) than that of 6B9 (5 x 10(6) M-1). MAb 3F5 recognized the apo A-II with a Kapp value of 1 x 10(9) M-1. The isolated lipoparticles Lp A-I and Lp A-I:A-II will be used to standardize an immunoassay for the measurement of these apo A-I-containing lipoprotein particles in human plasma.

Animals↗
PubMed1995

[Efficacy and tolerance of doxazosin in the treatment of isolated systolic hypertension in hypertensive patients over 60 years of age].

Isolated Systolic Arterial Hypertension (ISAH) is the most frequent form of AHT in the aged population, resulting in an increase of the cardiovascular risk, mainly at the cerebrovascular level. In this open non-comparative study, we analyze the effect of doxazosin, an alpha-adrenergic blocker in 40 patients older than 60 years, diagnosed of isolated systolic hypertension. After 2 weeks of lavage, the patients received treatment with doxazosin according to a monotherapy scheme, with progressive increase of the dose, from 1 to 16 mg/day during a period of 14 weeks. Doxazosin significantly reduces the systolic and diastolic arterial pressure (p < 0.001) with a therapeutical response in 86.5% of the cases, using an average dose of 3.4 mg/day and without observing modifications in the heart rate. This drug improves the lipidic profile, with a reduction of the plasmatic levels of total cholesterol and cholesterol linked to low density proteins (LDL) with p < 0.05 and a reduction of triglycerides. Among the 40 patients included in the study, 10 (25%) referred side effects; there were 2 drop-outs (5%) and the dose had to be reduced in 2 patients (5%). In conclusion, doxazosin shows its antihypertensive effectiveness in the treatment of isolated systolic hypertension in patients older than 60 years and it is well tolerated by most of the patients, improving at the same time the lipidic profile. Hence, it contributes to the reduction of the cardiovascular morbidity-mortality in this group of patients.

Age Factors↗
PubMed1994

[Outbreak of measles at a vocational training school].

BACKGROUND: A measles outbreak which started in the technical institute Els Ports in Albocacer (Castellón), and involved nearby towns was studied. METHODS: The outbreak was described using a retrospective cohort study to estimate the efficacy of the antimeasles vaccination (EV) by a questionnaire distributed in the institute. Response rate was 80.7%. A clinical definition of measles was used with EV being calculated by 2 different formulas. Antimeasles vaccination coverage (VC) in primary schools of the towns involved was also assessed. RESULTS: The outbreak occurred from February to April 1992, including 13 cases of measles (mean age: 13.6 +/- 2.7 years). Eleven patients (84.6%) had not been vaccinated. The attack rate the above mentioned institute was 9.1% (8 cases/88 students) with VC of 40.9%. An association was found only between being vaccinated and not having measles, relative risk 0.07 (confidence limits [CL] 95%: 0.01-0.50). EV was 92.9% (CL 95%: 50-99%) using the traditional formula and 96.2% (CL 95%: 88.2-100%) using the new formula. The VC in the schools was 92.3%. Vaccination with the triple viral vaccine was recommended to susceptible individuals. CONCLUSIONS: Despite specific vaccination measles continues to produce epidemics. A second dose of the triple viral vaccine is recommended for being included in the vaccination calendar between the age of 6 and 14 years.

Adolescent↗