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J M Muñoz

Publications and source records attributed to J M Muñoz.

At least 19 recordsLinked to original sources
PubMed2006

Radon measurements with a PIN photodiode.

Silicon photodiodes are well suited to detect alphas coming from different sources as neutron reactions or radon daughters. In this work a radon in air detecting device, using an 18x18 mm silicon PIN photodiode is studied. The ionized airborne decay products formed during radon diffusion were focused by an accelerating high voltage to the PIN surface. Several conducting rings were disposed inside a cylindrical PVC vessel in such a way that they reproduced the electric field created by a punctual charge located behind PIN position. Alpha spectra coming from the neutral and ionized species deposited on the PIN surface, dominated by 218Po and 214Po progeny peaks, were recorded for varying conditions. Those include radon concentration from a Pylon source, high voltage (thousands of volts) and PIN inverse bias voltage. Different parameters such as temperature and humidity were also registered during data acquisition. The increase in the particle collection efficiency with respect to zero electric field was compared with the corresponding to a parallel plates configuration. A discussion is made in terms of the most appropriate voltages for different radon concentrations.

Air Pollutants, Radioactive↗
PubMed2003

Analysis of the recent storm record in the southwestern Spanish coast: implications for littoral management.

This work compares the geomorphologic evolution of the Huelva coast (SW Spain), some climatic-oceanographic data of the Cádiz Gulf and the recent storm record of this zone, covering the last 4 decades (1956-1996). An interesting correlation was found between the southwestern wind periodicity, the number of storm periods and the beach ridges observed in the main spits (El Rompido and Doñana). The spectral analysis of the wind time series permits to establish two most probable levels of periodicity: 6 and 9-10 years. Both periods coincide with the storm record and the creation of new beach ridges after a high-energy period. Beach damage, another storm-induced effect, was analysed by deducing different implications for the future management of tourist localities.

Disasters↗
PubMed2003

Central tumour necrosis factor-alpha mediates the early gastrointestinal motor disturbances induced by lipopolysaccharide in sheep.

Cytokines are involved in fever and other symptoms of the acute phase response induced by endotoxins. The aim of this work was to study the involvement of central tumour necrosis factor-alpha (TNF-alpha) in the changes induced by lipopolysaccharide (LPS) on gastrointestinal (GI) motility in sheep. Body temperature and myoelectric activity of the antrum, duodenum and jejunum was recorded continuously. Intravenous (i.v.) administration of LPS (0.1 micro g kg-1)-induced hyperthermia, decreased gastrointestinal myoelectric activity and increased the frequency of the migrating motor complex (MMC). These effects started 40-50 min after LPS and lasted for 6-7 h. TNF-alpha (50 and 100 ng kg-1) mimicked these effects when injected intracerebroventricularly (i.c.v.) but not i.v. Pretreatment with soluble recombinant TNF receptor (TNFR:Fc, 10 micro g kg-1, i.c.v.) abolished the TNF-induced actions and reduced those evoked by LPS. Furthermore, the effects induced by either LPS or TNF were suppressed by prior i.c.v. injection of indomethacin (100 micro g kg-1). In contrast, the i.v. injections of TNFR:Fc or indomethacin were ineffective. Our data suggest that LPS disturbs GI motility in sheep through a central pathway that involves TNF-alpha and prostaglandins sequentially.

Animals↗
PubMed2001

Primary orbital liposarcoma: case report and review of the literature.

Primary orbital liposarcoma is an extraordinarily rare tumour. Lack of specific diagnostic findings, scarcity of published series and a primary anatomical location make its management complicated. Surgery should conserve visual function in well located, low-grade tumours that do not invade ocular structures. Complementary RT should also be performed.

Biopsy, Needle↗
PubMed2001

[In vitro susceptibility to ganciclovir and foscarnet of cytomegaloviruses].

Ganciclovir is the drug of choice for the treatment of acute cytomegalovirus infections. This antiviral agent is a nucleoside analog of guanine whose activity is dependent upon its intracellular phosphorylation to the triphosphate derivative. Foscarnet is used to treat immunosuppressed patients such as organ transplant recipients and AIDS patients with cytomegalovirus who do not tolerate or develop resistance to ganciclovir. Foscarnet is a pyrophosphate analog that directly inhibits viral DNA polymerase. Resistant isolates have been recovered from immunocompromised patients treated with both anticytomegalovirus compounds. The aims of this study were to prepare a plaque reduction assay to study the in vitro susceptibility of cytomegalovirus to ganciclovir and foscarnet, and to apply it to the knowledge of in vitro susceptibility values of cytomegalovirus isolated from clinical samples. Eighty isolates from patients who had never been treated with ganciclovir or foscarnet were tested for antiviral susceptibility. The plaque reduction assay took 6-8 weeks. The results are expressed as ID(50) (inhibitory dose 50), and the ID(50) values of ganciclovir were between 2.14 and 13.49 microM. The ID(50) for ganciclovir was higher that 12 microM in only two cases (2%). The molecular study of the DNA of these did not show any mutation in the UL97 gene. The ID(50) values of foscarnet were between 46.65 and 460.22 microM. In 78 cases (98%) foscarnet ID(50) was lower than 400 microM. These results were comparable with those obtained by other authors. To summarize, the frequency of cytomegalovirus strains resistant in vitro to ganciclovir and foscarnet in previously untreated patients was low and when it was present it did not involve therapeutic failure since the patients progressed favorably.

Antiviral Agents↗
PubMed2001

[Clinical utility of susceptibility testing of herpes simplex virus to acyclovir].

In vitro susceptibility to acyclovir of 96 strains of herpes simplex virus isolated from 80 immunocompromised patients attended in our hospital was studied by the cytopathic effect reduction assay. Ninety-eight percent (61/62) of herpes simplex virus 1 strains and 91% (31/34) of herpes simplex virus 2 strains were inhibited by acyclovir concentrations lower than 3 mg/l. In 5% of the patients herpes simplex strains resistant to acyclovir (ID(50) >3 mg/l) were isolated. Ninety-eight percent of the lesions caused by herpes simplex viruses susceptible to acyclovir (ID(50) <3 mg/l) resolved independently of treatment. In two cases, the cytopathic effect reduction assay was not able to predict treatment failure and persistance of the lesions was not always associated with isolation of a resistant strain in vitro. In four cases, isolation of a strain resistant to acyclovir was not indicative of treatment failure. In conclusion, we believe there is no need to routinely test susceptibility of herpes simplex viruses to acyclovir and that susceptibility testing should be indicated only in patients in whom lesions persist and other causes have been ruled out.

Acyclovir↗
PubMed2000

Cleistogamous capitulum in Centaurea melitensis (Asteraceae): heterochronic origin.

Cleistogamous capitula formed by Centaurea melitensis display a number of morphological and functional changes with respect to chasmogamous capitula that ensure self-fertilization. Because no studies have hitherto addressed the evolution of cleistogamy in Asteraceae, it was considered useful to ascertain whether these changes are attributable to one or more of the heterochronic processes reported in the literature. Bivariate allometric analyses were performed, and changes were represented graphically using Gould's clock models for size, shape, and age of several capitulum and floret structures. Results suggest that the partially paedomorphic appearance of cleistogamous with respect to chasmogamous capitula is attributable to three processes: (1) early onset of floral development (predisplacement), (2) decreased growth rate of the whorls studied (except gynoecium width) and (3) early offset time (progenesis). The latter appears to play the most significant role in the origin of the cleistogamous capitulum.

Journal Article↗
PubMed1999

Parenteral infusions bacterial contamination in a multi-institutional survey in Mexico: considerations for nosocomial mortality.

BACKGROUND: Parenteral infusions can be contaminated during administration (extrinsic contamination). A previous survey found that extrinsic contamination was not uncommon in a hospital in Mexico with lapses in aseptic techniques. To determine whether this problem exists in other similar institutions, we undertook a multi-institutional study. METHODS: We surveyed 6 hospitals (A to F) lacking an infection control committee to determine the level of extrinsic contamination. We visited each hospital and obtained samples of all the parenteral infusions in use, drawing 0.5-1 mL from the tubing injection port. Quantitative and qualitative bacterial cultures were performed. Chlorine levels of the tap water were measured. Visits were repeated until the survey was completed. RESULTS: A total of 751 infusions were cultured, of which 16 (2.13%) were contaminated. Hospital contamination rates varied from zero to 5.56%. Klebsiella pneumoniae was the most common isolate (10 cases). During the first sampling day in hospital C, the 7 infusions from the pediatric ward were found to be contaminated with a similar K pneumoniae strain. In-service education was started in this hospital. Infusion contamination was eliminated followed by a reduction in mortality rate. Overall, a higher risk for infusion contamination was noted for pediatric patients (P =.01, odds ratio = 3.28, 95% CI, 1.10-9.91) and in wards with inadequate water chlorine levels (P =. 02, odds ratio = 3.64, 95% CI, 1.08-13.51). CONCLUSIONS: If the hospitals surveyed are representative of others in developing countries, an endemic level of parenteral infusion contamination could exist in many hospitals throughout the world.

Adult↗
PubMed1999

[Control of pediatric nosocomial bacteremia by a program based on culturing of parenteral solutions in use].

OBJECTIVE: As Klebsiella, Enterobacter and Serratia are capable of growth in i.v. fluids and these bacteria are commonly implicated in nosocomial bacteremia, a control strategy through microbiological surveillance of in-use parenteral solutions is proposed. MATERIAL AND METHODS: A second level general teaching hospital, serving low-income patients. Through four consecutive strategies, a continuous surveillance program of i.v. fluids sterility in pediatric wards was stablished in 1992. During the first stage all of the in-use solutions were cultured. During the second stage randomly selected samples were studied. Third stage was designed as a case-control study. The last stage included samples drawn in convenience. Positive cultures point out eventual infusion mishandling, as well as high-risk areas and patients. RESULTS: After culturing 1940 parenteral solutions, infusion contamination rates decreased from 29.6% in 1992 to 12.9% in 1997 (p < 0.001). The proportion of Gram-negative rods isolated from blood cultures went from 72.7% to 40.85% (p < 0.0001), and the nosocomial bacteremia rate dropped from 3.12 to 1.54 per 100 discharges. CONCLUSIONS: The program has enabled us to: 1) Detect and control eventual bacteremia outbreaks; 2) Assess the endemic infusion contamination rate; 3) Arouse healthcare workers awareness about infusion line precautions; 4) Have a suitable surveillance strategy according to our laboratory's workload.

Bacteremia↗
PubMed1998

Perforation of the pharynx caused by blunt external neck trauma.

We present two cases of a rare entity: pharyngeal perforation caused by blunt external neck trauma. In both cases the patients were asymptomatic for the first 24 h and the results of laryngoscopic study were negative, and it was only possible to demonstrate rupture through the radiologic findings. Early diagnosis is essential as delay in treatment increases morbidity and mortality.

Accidents↗
PubMed1998

Initial disturbances of consciousness and resultant impaired awareness in Spanish patients with traumatic brain injury.

The purpose of this prospective, between-subjects study was to look at impaired awareness cross-culturally in patients with traumatic brain injury (TBI) and to relate impaired awareness after injury to the initial estimates of disturbed consciousness at time of injury. The study was conducted in community and inpatient and outpatient rehabilitation centers in Barcelona and Madrid. Participants were 30 persons with primarily moderate to severe TBI who could complete a written questionnaire concerning their functioning and 28 age- and gender-matched controls. A Spanish translation of the Patient Competency Rating Scale (PCRS) was administered to each participant. Relatives or significant others also completed this scale on each participant using the relative's version (PCRS-R). Difference scores, obtained by subtracting PCRS-R from PCRS-P (PCRS-P minus PCRS-R), were used as a marker of impaired awareness. Individuals with TBI were rated (by self and significant others) as being less competent than controls. Forty percent of Spanish patients with TBI who suffered severe injuries tended to overestimate their behavioral competencies. The PCRS-P minus the PCRS-R difference scores tended to correlate with admitting Glasgow Coma Scale (GCS) scores and retrospective estimates of posttraumatic amnesia (PTA). Initial disturbances of consciousness, one measure of severity of brain injury, appeared to relate to later measures of impaired self-awareness in Spanish patients with TBI. Non-brain-injured controls did not tend to report levels of competency that differed from their relatives' reports.

Adult↗
PubMed1996

[Supply of blood to heart surgery patients. Can transfusion habits be changed?].

OBJECTIVE: In cardiac surgery, patients might receive unnecessary blood transfusions, due to the lack of a uniform criteria for blood replacement. We set out to evaluate the effect of a transfusion education program on the homologous blood requirements of subjects undergoing cardiac surgery. METHODS: In June of 1993 a transfusion education program based on international criteria was designed and put into effect in the intensive care unit. Since that date, 133 patients (group 1), on whom we attempted to evaluate the effects of the program, were included, comparing them with 150 control patients (group 2) from the previous year. Multiple variables were analyzed, in order to confirm that the factors that could affect the use of blood did not differ between the two groups. The impact of these variables and the program on the homologous blood expenditures was measured with uni and multivariant analyses. RESULTS: Blood requirements of the patients during the first day of the postoperative period were 0.9 +/- 0.1 U in group 1 versus 1.8 +/- 0.1 U in group 2 (p < 0.001) and the requirements during their entire stay in ICU were 1.8 +/- 0.1 versus 2.6 +/- 0.1 (p < 0.005). There were significant differences between both groups: Hemoglobin level at the admission in ICU, anoxia time, extracorporal circulation time, and blood losses in the first 24 hours of their stay in ICU. However, the analysis of covariance showed that the transfusion program exerted an independent influence, apart from other variables, over the decrease of blood transfusions. Morbidity and mortality were similar in both groups. CONCLUSIONS: Transfusion habits can be modified, permitting a lesser consumption of homologous blood through the adoption of education programs adapted to the diseases in which they will be applied.

Blood Transfusion↗
PubMed1994

The clinical significance of suction drainage cultures.

A prospective study of 72 operations in which one or more suction drains were inserted, showed that cultures of the drains did not have any predictive value for the development of signs of infection. Protracted suction drainage could, however, increase the risk of postoperative infection.

Cefonicid↗
PubMed1983

Type Ic, a novel glycogenosis. Underlying mechanism.

The availability of a fresh, unfrozen liver biopsy specimen permitted the characterization of a unique type of glycogen storage disease. The subject, an 11-year-old female, showed the classic clinical symptoms of type I glycogenosis. However, her hepatic D-glucose-6-phosphate phosphohydrolase (EC 3.1.3.9) level as determined with detergent-activated homogenate was normal. The underlying mechanism was studied with intact microsomes from this fresh liver homogenate. Glucose-6-P phosphohydrolase was 75% latent, compared with 25% in normal controls matched for age and sex. Inorganic pyrophosphatase, PPi:glucose phosphotransferase, and carbamyl-P:glucose phosphotransferase activities of glucose 6-phosphatase were totally latent. While not observed with intact microsomes, these activities were fully manifested with detergent-disrupted microsomes. D-Glucose inhibited glucose-6-P phosphohydrolase activity of both intact and disrupted microsomes, but exogenous Pi inhibited only with the detergent-disrupted preparation. These observations are interpreted on the basis of the multicomponent glucose 6-phosphatase system of Arion et al. (Arion, W. J., Lange, A. J., Walls, H. E., and Ballas, L. M. (1980) J. Biol. Chem. 255, 10396-10406). All are consistent with a defect in T2, the putative translocase specific for Pi, PPi, and carbamyl-P. However, Pi produced endogenously from glucose-6-P hydrolysis within the microsomal lumen did not inhibit. This suggests that (i) a pathway for egress of Pi from the microsomal lumen exists independently of T2, (ii) T2 in this case works only unidirectionally, or (iii) the catalytic unit of glucose 6-phosphatase in situ has become desensitized to interactions with Pi, PPi, and carbamyl-P in this mutant model. Defects in both T1, the translocase specific for glucose-6-P, and T2 thus appear involved in this unique glycogenosis.

Child↗
PubMed1978

Influence of dietary fiber on trace element balance.

Five adult male volunteers were fed a diet containing (as percent of calories) 16% protein, 40% fat, and 44% carbohydrate, a diet similar to that consumed by many American males. Twenty-six grams of soft white wheat bran or corn bran were added to the daily bread, and the effects on zinc, iron, and copper balance were assessed during the last 12 days of each 30-day study period. The soft white wheat bran appeared to decrease retention of zinc in four subjects but not significantly so. Iron retention was similar in all three treatments. Copper balance was improved by addition of soft white wheat bran and to a lesser degree by corn bran. An apparent copper requirement of 1.28 mg/day for the volunteers was calculated by regression analysis.

Adult↗