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M Sierra

Publications and source records attributed to M Sierra.

79 records · Page 5Linked to original sources
PubMedDate not supplied

[Cross-cultural adaptation and validation of the Cambridge Depersonalisation Scale].

INTRODUCTION: The Cambridge Depersonalisation Scale (CDS) is a self-rating questionnaire constructed to capture the frequency and duration of depersonalization symptoms over the last six months. The instrument has proved to be valid and reliable and can be useful in both clinical and neurobiological research. METHODS: This paper presents the Spanish adaptation and validation of the CDS. The study was carried out in two stages. First, we developed the Spanish version of the CDS by means of a cross-cultural adaptation methodology. Second, the CDS was tried on a sample of 130 subjects: 77 patients meeting DSM-IV-TR criteria for schizophrenia, 35 with depression disorders and 18 with anxiety disorders. Scores were compared against clinical diagnoses (gold standard). Furthermore, all the subjects of the study were administered the following: Dissociation Experiences Scale (DES), Positive and Negative Syndrome Scale (PANSS), Beck's Depression Inventory (BDI), and the Hamilton Anxiety Rating Scale (HARS). RESULTS: 38 patients (29.2 %) had depersonalization symptoms. The scale showed high internal consistency (Cronbach's alpha > 0.9 and split-half reliability > 0.8) and a test-retest reliability of 0.391. Convergent validity was 0.65 (p < 0.001) and discriminant validity was 0.308 (p < 0.05). The area under the ROC curve was 0.94. A cut-off of 71 appears to be most useful (sensitivity and specificity were 76.3 % and 89.1 %, respectively). CONCLUSION: The Spanish version of the CDS has good reliability and validity, similar to the original instrument.

Adolescent↗
PubMedDate not supplied

[Effects of acidosis and alkalosis on the sarcoplasmic reticulum of the heart].

Some functions of dog cardiac sarcoplasmic reticulum have been studied in acidosis and alkalosis conditions in a range of pH from 6.0 to 7.8. Intravesicular water content at pH 6.0 is 4.7 microliter per mg of protein and diminished to 4 microliter, (15%) at pH 8.0; this correlates with a drop of 13.5% in turbidity. Ca2+-dependent ATPase has an optimal pH of 7.2 and a specific activity of 580 nanomoles of ATP hydrolyzed/min/mg protein. The activity of Basal ATPase or Mg2+-dependent is insensitive to changes of pH. Maximal calcium uptake attains 45.1 +/- 1.4 nanomoles per mg protein between pH 6.0 and 6.6. The accumulated calcium diminished progressively when pH was raised. The rate of calcium transport in steady state shows an optimal pH of 6.7. The calcium transport kinetics constants shows that reticulum has a maximal affinity for calcium between pH 6.87 and 7.02. The maximal velocity for transport diminished progressively between pH 6.1 to 7.16. During the calcium transport process pH is changed from acid to alkaline and the accumulated calcium is release proportionally to the pH increment. This effect shows to be reversible. Calcium accumulation and ATP hydrolysis are uncoupled at pH values higher than 6.6 because to the increase in the rate of calcium release. Values of pK and number of protons per mg of protein that dissociates from ionizable residues are 6.53 and 0.68 respectively for calcium dependent ATPase; 7.09 and 0.60 for calcium transport and 7.41 and 0.39 for calcium release. We conclude that the rate of transport and affinity of cardiac sarcoplasmic reticulum for calcium are optimal between pH 6.8 and 7.0 that is the reported range of intracellular pH of normal cardiac tissue. The data are in close agreement with the fall of contractility in acidosis. It is proposed a calcium release pathway sensitive to pH and different from that of calcium pump, exclusively for entrance.

Acidosis↗
PubMedDate not supplied

[Changes induced by hypertonic solutions in the transportation of calcium by the cardiac reticular sarcoplasma].

In the sarcoplasmic reticulum of the myocardium, celular organell which function is to regulate the cytoplasmic concentration of calcium in contraction and relaxation, we have studied the effect of hypertonic solutions of sucrose between 1 and 6.96 times the normal tonicity in order to observe the behavior of the internal linked or free calcium of this structure, as well as to prove the hypothesis that hypertonic solutions encourage the calcium exit of the sarcoplasmatic reticulum with the resulting signs of contractures. The following results were obtained: 1. The ATP hydrolisis and calcium transport rate are 14% and 90% respectively of the maximum speeds of 10(-5) M in calcium, while for concentrations of 10(-7) M or ess of the said cation, the transport rates and the ATPase do not reach 5% of the maximum values. 2. Between 1 and 2.54 times of the normal tonicity the calcium uptake remains between 400 and 500 nmoles of calcium/mg protein/min, the transported amount of calcium varies between 14 and 16 nmoles/mg protein and the rate of the ATP hydrolysis increases a 37% to 0.4 M in sucrose. 3. Between 0.4 and 1.2 M in sucrose of 2.54 to 6.96 times the isotonicity, the calcium transport rate velocity as well as the ATP hydrolisis are strongly inhibited. The vesicles volume minimizes and the amount of linked calcium remains within the control values, proving that the capacity of linking this cathion is independent from sarcoplasmic reticulum volume. These results show that the sarcoplasmic reticulum is involved in the contractures induced by hypertonic solutions in intact cells, since the osmolarity increase produces changes of volume which results in a decrease of the calcium transportation velocity or in an increase of the exit of said cathion.

Animals↗
PubMedDate not supplied

[Bacteremia in 13 general hospitals of the province of Barcelona. Prospective study of 1,674 episodes. Group of Microbiologists of the County Hospitals of Catalonia].

BACKGROUND: Clinical and microbiological description of bacteremias seen in 13 regional hospitals of Barcelona. METHODS: From January to December of 1991 a multicenter prospective study of bacteremia in regional hospitals was performed. The filiation, clinical findings and microbiological results were registered according to a common protocol. RESULTS: We studied 1674 episodes of bacteremia (13.8 per 1000 admissions). Patients were distributed into 3 groups according to age: under 14: 204 patients, between 14 to 65: 759 and over 65: 711 patients. Men account for 55% and women for 45% of episodes. The bacteremia was hospital-acquired in 24.4% of cases. The most common foci of infection were: urinary tract (32%), respiratory tract (14%), intestinal tract (8%), intravascular catheter (7%), biliary tract (7%) and unknown (10%). The most commonly isolated strains were: Escherichia coli 544 cases, Streptococcus pneumoniae 212, Staphylococcus aureus 139, coagulase negative staphylococi 85, Non-typhoid Salmonella 66, Neisseria meningitidis 63, Pseudomonas sp. 59, Enterococcus sp. 59 and Bacteroides sp. 58. Polimicrobial bacteremia was detected in 83 episodes (5%). Related mortality rate was 9.6% (161 patients).

Adolescent↗
PubMedDate not supplied

[Anaplastic carcinoma of the thyroid at the Instituto Nacional de la Nutrición Salvador Zubirán].

BACKGROUND: Anaplastic thyroid carcinoma (ATC) is a highly aggressive tumor with a median survival rate of 6 months. AIM: To analyze presentation, treatment, morphology, immunohistochemistry, and nuclear DNA analysis of a cohort of patients with ATC. PATIENTS AND METHODS: Twelve patients with ATC (11 female) with a mean age of 65 years were seen at our hospital from 1970-1995. The data were obtained from the clinical records and the morphology, immunohistochemic studies and DNA pattern were performed in slides obtained from archival specimens. RESULTS: Previous or coexisting thyroide disease was documented in 10 patients (9 multinodular goiters and one Grave's). The most frequent presentation was a rapidly growing tumor associated with dysphagia, cervical pain, hoarseness and dyspnea. A cold thyroid nodule was detected by thyroid scan in 10 patients. The most frequent subtype was the spindle cell variety. Papillary thyroid carcinoma coexisted in eight cases, two of them corresponded to the tall cell variant. Reactivity for S-100 protein and vimentin was studied in six patients: all were positive for S-100 protein and vimentin, 5/6 for epithelial membrane antigen, half for carcinoembriogenic antigen, 2/6 for thyroglobulin and calcitonin, and one for neuronal specific enolase. These six tumors showed a diploid DNA pattern. Tumor resection was achieved in 2/11 and none survived six years after diagnosis. CONCLUSIONS: ATC is a highly aggressive tumor coexisting with thyroid pathologies. Spindle cell variant is the most frequent with positive reactivity for S-100 protein, vimentin and epithelial membrane antigen. Most tumors have a diploid DNA content.

Aged↗
PubMedDate not supplied

[Neonatal infection by Streptococcus agalactiae. Multicenter study in the area of Barcelona, Spain].

BACKGROUND: Streptococcus agalactiae or streptococcus group B (SGB) is the main etiologic agent of early neonatal sepsis. A multicenter study was performed with the aim of determining the incidence and characteristics of this disease in our medium and contribute the design of an adequate prevention protocol. METHODS: Ten hospitals and two primary health care centers were implicated in the study; 103 microbiology confirmed episodes of SGB neonatal sepsis (blood and/or LCR positive) were reported from 1994 to 1996. RESULTS: The incidence of early SGB neonatal sepsis was 1.48/1,000 live births with a mortality of 8.7%. The cultures, for detecting the state of the SGB carrier were performed in only 26 (25%) of the patients. At least one of the factors described for risk of perinatal SGB infection was observed in 46% of the mothers, with the most frequent being prolonged amniorrhea (26%), intrapartum fever (17%), and early delivery (14%). At the time of delivery only 10.7% of the mothers received endovenous antibiotherapy. CONCLUSIONS: From these results the following recommendations have been made: a) detection of SGB carriers by the systematic practice of blood cultures in the last weeks of gestation and b) the administration of intrapartum antibiotic prophylaxis in both early births (< 37 weeks) and in all the SGB carriers should be undertaken. With these measures we aim to decrease the neonatal infections by streptococcus group B.

Adult↗