Search PubMed⌕ Search

Biomedical subjects

J Soto

Publications and source records attributed to J Soto.

At least 37 records · Page 2Linked to original sources

[Dyspepsia-related quality of life. Spanish adaptation and validation of the questionnaire Dyspepsia-Related Health Scale].

BACKGROUND: Dyspepsia affects about 25 % of the population and may cause an important decrease in quality of life. The aim of this work was to perform a Spanish validation and adaptation of the questionnaire DRHS (Dyspepsia Related Health Scale), a tool that assesses dyspepsia-related quality of life. PATIENTS AND METHOD: The study was carried out in 234 subjects, 163 with symptoms of dyspepsia and 71 health volunteers. Two rheumatologists, 2 general practitioners, 1 gastroenterologist, 1 clinical pharmacologist, 1 pharmacoepidemiologist and 1 psychologist were involved in the work. The process of adaptation and validation included translation and re-translation, pilot study in 16 patients, dimensionality, reliability and validity (of content, of construct, convergent, predictive and discriminative). RESULTS: The mean age was 49.1 years (SD: 18) and 60.7 % were females. The between-judges agreement rate of Hambleton and Rovinelli, which evaluates the content validity, was lower than 0.41. The construct validity assessed by the factorial analysis of responses showed that each subscale may be considered unidimensional in both health volunteers and individuals with dyspepsia. Reliability was satisfactory (Cronbach's alpha = 0.92) and stability of measures (test-retest) was excellent with a correlation coefficient of 0.95. The convergent validity, assessed by means of the EuroQoL, was only moderate with a correlation coefficient of 0.54 (p < 0.001). The predictive validity, assessed by administering the questionnaire 12 days after treating dyspepsia, showed a correlation coefficient of 0.47 between the two measures (p < 0.001). There was also a relationship between scores variation and outcome. CONCLUSIONS: The Spanish version of the DRHS, so-called QoL-PEI (questionnaire of quality of life related with problems of stomach and intestine), displays good metric properties and is able to predict the evolution of dyspepsia. The results of this study show that this tool is essentially unidimensional, yet it can be used on a multidimensional form to perform a differentiated assessment of each evaluated case.

Adolescent↗

Treatment of American cutaneous leishmaniasis with miltefosine, an oral agent.

There is no recognized oral treatment for American cutaneous leishmaniasis. A rising-dose, open-label phase I/II trial of the oral agent miltefosine against Colombian cutaneous leishmaniasis was conducted. Seventy-two male Colombian soldiers (mean weight, 67 kg) received miltefosine at 50-100 mg/day for 3 weeks (for 32 evaluable patients) or at 133-150 mg/day for 3-4 weeks (for 32 evaluable patients). The per-protocol cure rate for 50-100 mg/day was 21 (66%) of 32 patients. The per-protocol cure rate for 133-150 mg/day was 30 (94%) of 32 patients (P =.01, by use of Fisher's exact test). The historic per-protocol cure rate for standard injections of antimony is 93%. "Motion sickness" that did not interfere with normal duties was experienced by 40% of patients and was dose related. Vomiting and diarrhea were reported on approximately 2% of treatment days. In this uncontrolled study of oral miltefosine for treatment of patients with American cutaneous leishmaniasis, a dosage of approximately 2.25 mg/kg/day for 3-4 weeks was effective and tolerated.

Administration, Oral↗

Ferrocene-cyclam: a redox-active macrocycle for the complexation of transition metal ions and a study on the influence of the relative permittivity on the coulombic interaction between metal cations.

The reaction of 1,1'-ferrocene-bis(methylenepyridinium) salt with 1,4,8,11-tetraazacyclotetradecane-5,12-dione, followed by LiAlH4 reduction results in the formation of FcCyclam. Metal complexes of FcCyclam with M2+ = Co2+, Ni2+, Cu2+, and Zn2+ were synthesized from FcCyclam and the respective metal triflates. The complexation of Cu2+ and FcCyclam in CH3CN is preceeded by a rapid electron transfer, followed by a slower complex formation reaction and a reverse electron transfer. The protonation constants of FcCyclam and the stability constants for the Cu2+ complex of FcCyclam (logK = 9.26(4) for the formation of the [Cu(FcCyclam)]2+ complex) were determined in 1,4-dioxane/water 70:30 v/v, 0.1 moldm(-3), KNO3, 25 degrees C. By using FcCyclam one can selectively sense the presence of Cu2+ ions in the presence of Ni2+, Zn2+, Cd2+, Hg2+, and Pb2+ with a very large deltaE approximately 200 mV, depending on pH. The X-ray crystal structures of FcCyclam and of complexes with Co2+, Ni2+, Cu2+, and Zn2+ were determined and Fe-M2+ distances obtained: Fe-Co2+ 395.9, Fe-Ni2+ 385.4, Fe-Cu2+ 377.7, and Fe-Zn2+ 369.0 pm. The redox potential of FcCyclam is influenced in a characteristic manner by the complexation of M2+. A linear correlation of 1/r approximately/= deltaE [r = distance Fe-M2+ from crystal data, deltaE=-E1/2([M(FcCyclam)]2+) - E1/2(FcCyclam)] was found; this is indicative of a mainly Coulomb type interaction between the two metal centers. The nature of the Fe...M2+ interaction was also investigated by determining deltaE in several solvents (mixtures) of different dielectric constants epsilon. The expected relation of deltaE approximately/= 1/epsilon was only found at very high values of epsilon. At epsilon < 40 increased ion-pairing appears to reduce the effective positive charge at M2+ leading to progessively smaller values of deltaE with lowered epsilon. The dependence of deltaE and epsilon can be calculated semiquantitatively by combining the Fuoss ion-pairing theory with the Coulomb model.

Journal Article↗

Sex-specific determinants of HIV infection among injection drug users in Montreal.

BACKGROUND: Sex-specific issues have not been extensively addressed in studies of HIV prevalence, despite the strong implications of differences between men and women in the risk of HIV transmission. The objective of this study was to examine sex-specific behaviours associated with HIV infection among injection drug users in Montreal. METHODS: A total of 2741 active drug users (2209 [80.6%] men) were recruited between 1988 and 1998. Information was sought on sociodemographic characteristics, drug-related behaviour and sexual behaviour, and participants were tested for HIV antibodies. Sex-specific independent predictors of HIV prevalence were assessed by stepwise logistic regression. RESULTS: The overall prevalence of HIV among study subjects was 11.1%; the prevalence was 12.0% among men and 7.5% among women. In multivariate models, a history of sharing syringes with a known seropositive partner (odds ratio [OR] for men 2.44, 95% confidence interval [CI] 1.72-3.46; OR for women 3.03, 95% CI 1.29-7.13) and of sharing syringes in the past 6 months (OR for men 0.61, 95% CI 0.44-0.85; OR for women 0.32, 95% CI 0.14-0.73) were independently associated with HIV infection. Other variables associated with HIV infection were homosexual or bisexual orientation, cocaine rather than heroin as drug of choice, frequency of injection drug use, and obtaining needles at a pharmacy or through needle exchange programs (for men only) and obtaining needles at shooting galleries and being out of treatment (for women only). INTERPRETATION: These results support the hypothesis that risk factors for HIV seropositivity differ between men and women. These sex-related differences should be taken into account in the development of preventive and clinical interventions.

Adolescent↗

Effect of mitomycin-C on vocal fold healing in a canine model.

For evaluation of the effect of topical mitomycin-C on vocal fold healing and return of function after surgical excision of mucosa, 6 dogs underwent suspension microlaryngoscopy with bilateral microflap excision of vocal fold mucosa. Topical mitomycin-C, a chemotherapeutic agent and a fibroblast inhibitor, was applied randomly to one side, with the contralateral side serving as the control. Laryngeal videostroboscopy (LVS) was performed on each animal before the operation, at 2 weeks, and before sacrifice at 4 weeks. Both functional analysis with LVS and histologic analysis were performed in a blinded fashion to determine the effect of mitomycin-C on healing. Histologic analysis was augmented with computer morphometrics. The LVS revealed diminished mucosal wave vibration in the vocal folds treated with mitomycin-C, as well as a more atrophic appearance to the vibratory surface. The vocal folds treated with mitomycin-C showed fewer fibroblasts and less collagen within the superficial layer of the lamina propria than the control vocal folds (p < .05, Student's t-test, paired analysis). Inflammatory infiltrate was not significantly different between the two sides. Consistent with the known suppression of fibroblast proliferation by mitomycin-C, the treated vocal folds showed less connective tissue response to the surgical injury. In contrast to the reported positive effects of mitomycin-C on tracheal and glottic stenosis, the observed decrease in the healing response in the present study had negative consequences on the vocal fold vibratory pattern.

Administration, Topical↗

Plasmodium vivax clinically resistant to chloroquine in Colombia.

Chloroquine-resistant Plasmodium vivax has been the subject of numerous case reports and prospective studies from Oceania and Asia. In contrast, only case reports exist from the Americas. We performed a prospective study with 28-day follow-up of clinical responses to chloroquine in 2 P. vivax-endemic regions of Colombia. Three (11%) of 27 patients failed to respond to treatment with the standard regimen of chloroquine (1,500 mg of base over 3 days). One patient demonstrated RI resistance on Day 26; one patient demonstrated RI resistance due to recrudescence of blood stages on Day 11; and one patient demonstrated RII resistance of blood stages by never displaying clearing of peripheral parasitemia. All patients were successfully treated with primaquine, which has some blood stage efficacy against P. vivax, combined with a second course of chloroquine. Clinical resistance of P. vivax to chloroquine is present in Colombia and should be monitored in the Americas.

Animals↗

Assessment of hospital costs related to the diagnosis and treatment of upper gastrointestinal haemorrhages in patients consuming non steroid anti-inflammatory drugs.

BACKGROUND: Non-steroid anti-inflammatory drugs (NSAIDs) can produce haemorrhages of the digestive tract, whose treatment result in significant hospital costs. OBJECTIVE: The aim of this analysis has been to estimate hospital costs related to the treatment of digestive haemorrhages potentially caused by the intake of NSAIDs. MATERIAL AND METHODS: The study was conducted by reviewing the clinical history of all patients admitted in two tertiary Spanish hospitals during 1998 due to digestive haemorrhage following NSAID treatment. After the identification of cases, all resources consumed during their hospitalisation (concomitant medication, complementary examinations and tests, surgery, blood products consumption, inpatient consultations and length of stay in the hospital) until the complete resolution of each case, were recorded. RESULTS: Thirty-six percent of patients admitted due to digestive haemorrhage had taken some NSAID the same day of their hospitalisation (85.4%) or in previous days. The cost related to the treatment of these patients amounted to some 71 million pesetas for both hospitals, with a cost/patient of 434,407 pesetas. CONCLUSIONS: Given the high consumption of NSAIDs in our normal clinical setting, costs related to the diagnosis and treatment of digestive haemorrhages in hospitals are a highly significant burden for the National Health System.

Adolescent↗

[Severe gastrointestinal complications potentially associated with the use of non-steroidal anti-inflammatory agents: hospital treatment costs for the National Health System of our country].

BACKGROUND: Non-steroidal antiinflammatory drugs (NSAIDs) produce severe gastrointestinal (G-I) complications in 1-4% of cases which need to be treated into the hospital. The aim of this study has been to assess the hospital cost secondary to treat these complications in our National Health Service (NHS). MATERIAL AND METHODS: In the first phase a cross-sectional study was performed in order to know the number of patients who were hospitalized due to a severe G-I complication during 1998 in two tertiary hospital in our country. It was reviewed their clinical charts to know whether they had taken any NSAIDs. In those positive cases all resources used during the hospitalization were collected. RESULTS: In both hospitals studied 38.1% of hospitalized patients for a severe G-I complication had taken any NSAIDs during the same day or previous days. The cost/patient was of 389,831 pesetas. During 1998 in the whole NHS there were 54,623 hospitalizations owing to the same reason. Assuming that 38.1% of them had also taken any NSAIDs, 20,811 patients would have suffered a severe G-I complication potentially due to the intake of NSAIDs. Extrapolating the cost/patient obtained in both hospitals to the global number of patients hospitalized into the NHS, the cost of treating all severe G-I complications related to the consumption of NSAIDs during 1998 was of 8,112 millions pesetas. CONCLUSIONS: Bearing in mind the elevated prevalence of osteo-articular pathology in our country and the high consumption of NSAIDs for its treatment, the coming of new therapeutic options with a better safety profile would mean an important resources' saving for our NHS.

Anti-Inflammatory Agents, Non-Steroidal↗

An ab initio study of the photochemical decomposition of 3, 3-dimethyldiazirine

Photochemical decomposition of 3,3-dimethyldiazirine (DMD) has been computationally investigated by using high-level ab initio calculations in conjunction with the 6-31G and cc-pvdz basis sets. The geometries of minima and transition states, as well as conical intersection points in the seam of crossing of two surfaces, have been optimized with the complete active space self-consistent field (CAS-SCF) method, and their energies, recalculated with second-order multireference perturbation (CAS/MP2) theory. The reaction path starting at the excited n-pi state of DMD is predicted to occur via a nonadiabatic mechanism, giving carbene and molecular dinitrogen (both in their singlet ground states) as the main products; the computed barrier height (1.0 kcal mol(-)(1)) agrees well with the experimental estimate of the activation energy in the singlet excited state (0.0-1.5 kcal mol(-)(1)). Ground state of dimethylcarbene is the only species where a 1,2-hydrogen shift takes place, being the only source of propene. The calculated potential energy barrier height for dimethylcarbene to propene isomerization (2.6 kcal mol(-)(1)) agrees well with the observed activation energy (2.56 kcal mol(-)(1)). No evidence for rearrangement in the first singlet excited state of DMD has been found; such a process would lead to a higher activation energy than the observed one. Consequently, 1,2-hydrogen migration concurrent with N(2) extrusion in the excited state has been ruled out.

Journal Article↗

Autohydrolysis of plant polysaccharides using transgenic hyperthermophilic enzymes.

Commercial bioprocessing of plant carbohydrates, such as starch or cellulose, necessitates the use of commodity enzyme additives to accelerate polysaccharide hydrolysis. To simplify this procedure, transgenic plant tissues constitutively producing commodity enzymes were examined as a strategy for accelerating carbohydrate bioprocessing. Hyperthermophilic glycosyl hydrolases were selected to circumvent enzyme toxicity, because such enzymes are inactive at plant growth temperatures and are therefore physiologically benign. Transgenic tobacco lines were established that produced either a hyperthermophilic alpha-glucosidase or a beta-glycosidase using genes derived from the archaeon Sulfolobus solfataricus. Western blot and immunoprecipitation analyses were used to demonstrate the presence of recombinant enzymes in plant tissues. Transgenic enzyme levels exhibited an unusual delayed pattern of accumulation while their activities survived plant tissue preservation. Transgenic plant protein extracts released glucose from purified polysaccharide substrates at appreciable rates during incubation in high-temperature reactions. Glucose was also produced following enzymatic treatment of plant extracts enriched for endogenous polysaccharides. Direct conversion of plant tissue into free sugar was evident using whole plant extracts of either transgenic line, and could be significantly accelerated in a synergistic manner by combining transgenic line extracts.

Blotting, Western↗

Basic fibroblast growth factor applied to the optic nerve after injury increases long-term cell survival in the frog retina.

The neuroprotective effects of basic fibroblast growth factor (bFGF) on the long-term survival of axotomized retinal ganglion cells (RGCs) were studied in the frog Rana pipiens. Cell loss was quantified in different regions of the ganglion cell layer using Nissl staining and tetramethylrhodamine dextran amine backfilling. All regions of the retina showed a significant decrease (32-66%) in RGC numbers between 4 and 16 weeks after axotomy. Some cells showed morphological and biochemical signs of apoptosis. A single application of bFGF to the optic nerve stump at the time of axotomy protected many of the cells 6 weeks after the injury, but this effect was lost by 12 weeks. A second application of bFGF, 6 weeks after the injury, rescued many RGCs at 12 weeks. In contrast, single or double injections of bFGF into the eyeball had no effect on RGC survival. Axotomized RGCs were significantly enlarged and elongated after axotomy, and these morphological changes were increased by bFGF treatment. In the normal retina and optic nerve, immunocytochemical staining showed bFGF-like immunoreactivity (-LI) in the pigment epithelial layer, in the outer segments of photoreceptors, and in occasional RGCs. Strong bFGF-LI was present in Müller cells and in optic nerve astrocytes and oligodendrocytes. FGF receptor-LI was present in photoreceptors, outer plexiform layer, retinal ganglion cell axons, and Müller cells. FGF receptor-LI was also observed in optic nerve glia.

Animals↗

Mutations in the CYP21 B gene in a Chilean population with simple virilizing congenital adrenal hyperplasia.

Steroid 21-hydroxylase deficiency (21OHD) compromises about 95% of all cases of congenital adrenal hyperplasia. We have characterized the disease-causing mutations in the steroid 21-hydroxylase genes of 19 Chilean patients (12 females and 7 males) with the simple virilizing (SV) form of 21OHD and compared them with other SV-populations. Using allele-specific polymerase chain reaction, we identified lesions in 28 chromosomes out of 38 tested (73.7%). The most frequent finding was the mutation I173N=12/38 (31.6%) similar as described in Caucasian, Asian and other Hispanic populations, where this mutation represents around 20-40% of the genetic defects in the CYP21B gene. The mutation V282L=4/38 (10.5%) and deletion (Del) or large gene conversion (LGC)=3/38 (7.9%) were also frequently detected. Only 2 alleles carried the mutation I2 splice (5.3%), this frequency is lower than that reported in Caucasian or in Mexican populations. We did not find alleles with the mutations R357W, Cluster E6, P31L and P454S in these patients. The complete genotype was determined in 11/19 patients (58%) and one allele in 6/19 patients (31.6%). In summary, about 30% of the Chilean population with SV 21OHD presented the missense mutation I173N as described in other populations. The frequency of the other lesions showed differences even between populations with similar genetic background.

Adrenal Hyperplasia, Congenital↗

Radon progeny activity in sweat following radon exposure in a warm and humid environment.

The objective was to evaluate whether activity of radon progenies can be detected in sweat following speleotherapeutic radon exposure (40 kBq/m3) in a warm (38 degrees C) and humid (relative humidity > 70%) environment. A group of 11 male patients with spondyloarthropathy (n = 6) or non-inflammatory rheumatic diseases (n = 5) underwent a 1-h treatment in the gallery of the Gasteiner Heilstollen, and 20 min after leaving the treatment area radon progeny activity was measured in sweat by utilizing a special filter set. The results suggest that radon is discharged with sweat, causing a significant activity of radon and radon progenies on the skin. This finding may be important from a clinical point of view, since specialists experienced in radon therapy have repeatedly emphasized the importance of the degree of radioactivity on the skin for the effectiveness of treatment. It has even been claimed that the skin is the major target for radon therapy, possibly because of the influence on Langerhans' cell function.

Fever↗

Primary hyperaldosteronism in essential hypertensives: prevalence, biochemical profile, and molecular biology.

There is evidence that primary aldosteronism (PA) may be common in patients with essential hypertension (EH) when determinations of serum aldosterone (SA), plasma renin activity (PRA), and the SA/PRA ratio are used as screening. An inherited form of primary hyperaldosteronism is the glucocorticoid-remediable aldosteronism (GRA) caused by an unequal crossing over between the CYP11B1 and CYP11B2 genes that results in a chimeric gene, which has aldosterone synthase activity regulated by ACTH. The aim of this study was to evaluate the prevalence of PA and the GRA in 305 EH patients and 205 normotensive controls. We measured SA (1-16 ng/dL) and PRA (1-2.5 ng/mL x h) and calculated the SA/PRA ratio in all patients. A SA/PRA ratio level greater than 25 was defined as being elevated. PA was diagnosed in the presence of high SA levels (>16 ng/dL), low PRA levels (<0.5 ng/mL x h), and very high SA/PRA ratio (>50). Probable PA was diagnosed when the SA/PRA ratio was more than 25 but the other criteria were not present. A Fludrocortisone test was done to confirm the diagnosis. GRA was differentiated from other forms of PA by: the aldosterone suppression test with dexamethasone, the high levels of 18-hydroxycortisol, and the genetic detection of the chimeric gene. In EH patients, 29 of 305 (9.5%) had PA, 13 of 29 met all the criteria for PA, and 16 of 29 were initially diagnosed as having a probable PA and confirmed by the fludrocortisone test. Plasma potassium was normal in all patients. The dexamethasone suppression test was positive for GRA in 10 of 29 and 18-hydroxycortisol levels were high in 2 of 29 patients who had also a chimeric gene. In normotensive subjects, 3 of 205 (1.46%) had PA, and 1 of 205 had a GRA. In summary, we found a high frequency of normokalemic PA in EH patients. A high proportion of PA suppressed SA with dexamethasone, but only a few had a chimeric gene or high levels of 18-hydroxycortisol. These results emphasize the need to further investigate EH patients.

Aldosterone↗