Biomedical subjects

A Rodríguez

Publications and source records attributed to A Rodríguez.

At least 163 records · Page 9Linked to original sources

PubMed1998

[Ambulatory monitoring of A/EEG in the preoperative assessment of partial epilepsy].

INTRODUCTION: Electroencephalography, together with new neuroimaging techniques is still the main diagnostic tool for pre-operative assessment of epilepsy. The electrical episodes, both ictal and intercritical, are random paroxystic phenomena with regard to presentation, so the conventional EEG is sometimes of limited value. Therefore, in recent years, long duration EEG monitoring techniques have been favoured, with or without simultaneous recording of clinical behaviour, permitting recording for an indefinite period. Amongst these techniques, monitoring using cassette recording (A/EEG) if of specific interest since it permits the study of outpatients. OBJECTIVE: The main aim of surgical treatment of epilepsy is to abolish or reduce the number of crises. Therefore it is essential to localize the epileptogenic area as precisely as possible. The A/EEG has made a major contribution to the procedure of pre-operative assessment because of the considerable information it gives regarding the recording and character of the crises. MATERIAL AND METHODS: During the past three years, preoperative assessment has been carried out in our hospital on 44 patients with drug-resistant partial epilepsy. A total of 103 long duration cassette recordings (A/EEG) were done. Of these, 58 were done with surface electrodes and individualized set-up depending on the EEG findings, 8 with semi-invasive (sphenoid) electrodes, and 37 recordings used implanted sub-dural electrode strips. RESULTS: Combined study of the results obtained with these techniques permitted localization of the lesive-epileptogenic complex in 42 of these patients. We present the results obtained and conclude that A/EEG monitoring is useful in the pre-operative assessment of epilepsy.

Adolescent↗

PubMed1998

[Metanephric adenoma. A new embryonal tumor of the kidney].

Metanephric adenoma is a kidney tumour first identified in 1988 and classified within the group of nephroblastic tumours. It is described as a benign tumour with no capacity to become malignant or metastatic, predominant in women in a 2:1 ratio relative to men, and which can develop at any point in life. In most cases, it is incidentally found as a result of an abdominal ultrasound study for signs and symptoms unrelated to the kidney. Less commonly it presents with pain, polycythemia, haematuria or palpable mass. The key radiologic sign is calcification, which occurs in a statistically higher proportion than in any other renal neoplasia. From the pathoanatomical point of view, the tumour consists of small acinus separated by acellular stroma resembling the hamartomatous elements of nephroblastomatosis and Wilms' tumour. This paper contributes one case of metanephric adenoma, the first one in the national literature.

Adenoma↗

PubMed1998

[Clinical characterization of patients with multiple sclerosis defined in Cuba].

INTRODUCTION: Since 1975 no studies have been done in Cuba defining the clinical characteristics of patients with multiple sclerosis (MS). OBJECTIVE: To describe the characteristics of a group of Cuban patients with definite clinical MS. MATERIAL AND METHODS: Fifty eight patients with definite clinical MS were studied (Poser et al) with normal motor (VCM) and sensory (VCS) conduction velocities. Tests were done on them: clinical scale (Scripps), incapacity (EDSS) and quality of life (Steps), together with various complementary tests. Each patient was classified according to the way in which the disease evolved. Also the two commonest clinical types were compared and we applied the difference test between percentages of non-paired samples with an alfa level of 0.05. RESULTS: Onset of the illness in most cases was before the age of 40 (86.1%), 75.9% were women and 82.8% were white. In 15.3% there was a family history of MS. In 25.9% there were psychiatric disorders and trigger factors (43.1%. The most frequent initial symptoms were pyramidal (48.3%) sensorial (41.4%) and cerebellar (39.7%). Scripps scale scores were < 80 in 60.2%, in EDSS < 5 (61.9%) and in the Clinical Steps < 3 in 65.4%). Motor potentials (81.9%) somatosensory potential (PESS) (72.3%) and magnetic resonance imaging (MR) (76.4%) were the most abnormal results. Exacerbation-remission (ER) was the most frequent type of evolution (53.4%) generally affecting patients aged under 40 years old (p = 0.02), EDSS < 5 (64.4%), Scripps > 80 (61.2%), Steps < 3 (95.6%), pyramidal system involvement (58.5%), cerebellar (29.2%) and MRI abnormality (80%). The progressive primary form (PP) was the second most frequent (29.3%); 29.4% were under 40 years of age, had more marked changes in all functional system (100%), degree of incapacity and quality of life (100%). PESS (92.5%); the urodynamic tests 58.85%) were less positive on MRI (54.5%) as compared with the ER form. CONCLUSIONS: The differences found between the clinical forms ER and II indicate that there is greater deterioration in the PP form, probably due to age and more cerebellar and spinal cord involvement.

Adolescent↗

PubMed1998

[Behavioral evaluation of the unilateral lesion model in rats using 6-hydroxydopamine. Correlation between the rotations induced by D-amphetamine, apomorphine and the manual dexterity test].

INTRODUCTION: Evaluation of rotatory activity induced by dopaminergic agonists is the most widely used test of conduct for the measurement of dopaminergic depletion of a unilateral lesion of the striatonigral pathway caused by 6-hydroxydopamine (6-OHDA) in rats, since it is quantitatively related to the extension of the dopaminergic denervation. OBJECTIVE: The objective of this study was to evaluate, from different angles, the changes in conduct seen in the model of unilateral lesion with 6-OHDA and to establish correlation with the rotation induced by D-amphetamine and by apomorphine and the ladder test. MATERIAL AND METHODS: Male Wistar rats were used. Lesions were produced in the SNpc by stereotactic injection of 6-OHDA into the right hemisphere and the effectiveness of the lesions was studied using the rotary conduct induced by D-amphetamine and apomorphine. The motor ability of the front legs was measured by the ladder test, carried out under standard and forced conditions. RESULTS: All the animals with lesions had difficulty in reaching food with both legs, although the most pronounced deficit was in the leg contralateral to the lesion. The ladder test correlated better with rotatory activity induced by apomorphine than by D-amphetamine. CONCLUSION: The animals with most dopamine loss showed most deficient use of their front legs.

Animals↗

PubMed1998

Assessment of nutritional status in a population of recently hospitalized patients.

Malnutrition in the hospital is not a new or rare problem, however, it is often unrecognized. In order to determine the baseline nutritional characteristics of recently hospitalized patients, we assessed the nutritional status of all medical in-patients between April and December 1994 in a large hospital in the province of Buenos Aires. One hundred and seventy patients were derived from the Internal Medicine ward and 176 patients from the General Surgery ward. Surgery patients were younger (median: 46 years vs 58 years of the Medicine patients). Among Medicine patients, cardiovascular and respiratory afflictions were the most common (30%), while gastrointestinal disorders were more often seen in Surgical patients (71%). A weight loss of more than 10% (%WL) was found in 12% of the Medicine and Surgery patients and a body mass index (BMI) of less than 19 kg/m2 was observed in about 5% of both groups. Ten percent of the Medicine patients and 14% of the Surgery patients were overweight. A mid-upper arm muscle circumference (MUAMC) less than the fifth percentile was found in 11% of the Medicine patients but in only 3% of the Surgery patients. These results suggest that this population of recently hospitalized patients is at high-risk for medical complications. Therefore, early nutrition assessment and appropriate nutrition intervention are required to improve clinical outcome and help reduce the cost of health care.

Adult↗

PubMed1998

[Traumatic ruptures of the peroneal tendons treated by free autologous tendon graft].

The authors report a case of traumatic rupture of both peroneal tendons following a varus injury of the ankle. The lesion was diagnosed late and was successfully treated by a free autologous tendon graft using the distal end of the peroneus brevis tendon to restore the peroneus longus, which was also reinforced by a plantaris tendon graft. The authors stress the interest of suspecting the lesion after acute varus trauma and in cases of chronic instability of the ankle.

Ankle Injuries↗

PubMed1997

[Prenatal molecular genetic diagnosis and treatment of congenital adrenal hyperplasia due to 21-hydroxylase deficiency].

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21-OH), in its severe forms, produces virilization of the external genitalia of the affected female fetus. Early treatment with dexamethasone of the pregnant mother at risk of a fetus with 21-OH deficiency avoids the masculinization of the affected female fetus. We present a pregnant mother, where the prenatal diagnosis was established by DNA analysis of a chorionic villous sample obtained in the 9th week of gestation. Molecular analysis showed the female fetus to be affected of 21-OH deficiency. Maternal treatment with dexamethasone started on the 6th week of gestation has prevented the virilization of the affected baby. No significant side effects have been encountered. Prenatal diagnosis and treatment for 21-OH deficiency is effective and safe, as is described in the literature. This is the first case in Spain where both prenatal molecular diagnosis and treatment for 21-OH deficiency have been reported.

Adrenal Hyperplasia, Congenital↗

PubMed1997

Lysosomes behave as Ca2+-regulated exocytic vesicles in fibroblasts and epithelial cells.

Lysosomes are considered to be a terminal degradative compartment of the endocytic pathway, into which transport is mostly unidirectional. However, specialized secretory vesicles regulated by Ca2+, such as neutrophil azurophil granules, mast cell-specific granules, and cytotoxic lymphocyte lytic granules, share characteristics with lysosomes that may reflect a common biogenesis. In addition, the involvement of Ca2+ transients in the invasion mechanism of the parasite Trypanosoma cruzi, which occurs by fusion of lysosomes with the plasma membrane, suggested that lysosome exocytosis might be a generalized process present in most cell types. Here we demonstrate that elevation in the intracellular free Ca2+ concentration of normal rat kidney (NRK) fibroblasts induces fusion of lysosomes with the plasma membrane. This was verified by measuring the release of the lysosomal enzyme beta-hexosaminidase, the appearance on the plasma membrane of the lysosomal glycoprotein lgp120, the release of fluid-phase tracers previously loaded into lysosomes, and the release of the lysosomally processed form of cathepsin D. Exposure to the Ca2+ ionophore ionomycin or addition of Ca2+-containing buffers to streptolysin O-permeabilized cells induced exocytosis of approximately 10% of the total lysosomes of NRK cells. The process was also detected in other cell types such as epithelial cells and myoblasts. Lysosomal exocytosis was found to require micromolar levels of Ca2+ and to be temperature and ATP dependent, similar to Ca2+-regulated secretory mechanisms in specialized cells. These findings highlight a novel role for lysosomes in cellular membrane traffic and suggest that fusion of lysosomes with the plasma membrane may be an ubiquitous form of Ca2+-regulated exocytosis.

Adenosine Triphosphate↗

PubMed1997

Amphetamine derivative related deaths.

Amphetamine its methylendioxy (methylendioxyamphetamine methylenedioxymethylamphetamine, methylenedioxyethylamphetamine) and methoxy derivatives (p-methoxyamphetamine and p-methoxymethylamphetamine) are widely abused in Spanish society. We present here the results of a systematic study of all cases of deaths brought to the attention of the Madrid department of the Instituto Nacional de Toxicologia from 1993 to 1995 in which some of these drugs have been found in the cadaveric blood. The cases were divided into three categories: amphetamine and derivatives, amphetamines and alcohol, amphetamines and other drugs. Data on age, sex, clinical symptoms, morphological findings, circumstances of death, when known, and concentration of amphetamine derivatives, alcohol and other drugs in blood are given for each group. The information provided here may prove to be useful for the forensic interpretation of deaths which are directly or indirectly related to abuse of amphetamine derivatives.

Adolescent↗

PubMed1997

The CD94 and NKG2-A C-type lectins covalently assemble to form a natural killer cell inhibitory receptor for HLA class I molecules.

CD94, a type II membrane protein containing a C-type lectin domain, has been shown to be involved in natural killer (NK) cell-mediated recognition of different HLA allotypes. The inhibitory form of the CD94 receptor has recently been identified by the specific monoclonal antibody (mAb) Z199. Herein, we demonstrate that the inhibitory receptor is in fact a complex formed by the covalent association of CD94 with the NKG2-A molecule (Mr approximately 43 kDa), another member of the C-type lectin superfamily, and that Z199 mAb specifically recognize NKG2-A molecules. Although the NKG2-A-encoding cDNA has been known for several years, the corresponding protein and its possible function remained undefined. Moreover, we show that the NKG2-B protein, an alternatively spliced product of the NKG2-A gene, can also assemble with CD94. Remarkably, both NKG2-A and NKG2-B proteins contain cytoplasmic immunoreceptor tyrosine-based inhibitory motifs (ITIM). This may provide the molecular basis of the inhibitory function mediated by the CD94/NKG2-A receptor complexes.

Antigens, CD↗

PubMed1997

The human natural killer gene complex is located on chromosome 12p12-p13.

Natural killer (NK) cells preferentially express several type II glycoproteins of the calcium-dependent lectin superfamily. The genes coding for these molecules are clustered on the distal mouse chromosome 6 and on the rat chromosome 4 in a region designated the NK gene complex. To date, no definite evidence of the presence of a NK gene complex has been found in humans. Here we report the assignment by fluorescence in situ hybridization of the CD94 gene to human chromosome 12p12-p13, in the same region where the CD69 and NKG2A genes had been previously mapped. In addition, using a yeast artificial chromosome contig spanning this region we determined that the human CD94, NKG2A, NKG2C, NKG2E, and NKR-P1A (NKR) genes map to the short arm of chromosome 12. The distal to proximal position of these loci are: NKR- CD69 - CD94/NKG2A/NKG2C/NKG2E. These data demonstrate the existence of a human NK gene complex located within a 5.6 cM interval flanked by the genetic markers D12S397 and D12S89. The physical distance spanned by the NK gene complex in humans ranges between 0.7 and 2.4 megabases.

Animals↗

PubMed1997

Traumatic and nontraumatic perforation of hollow viscera.

Hollow viscus injuries are usually managed with few complications. However, if their diagnosis is delayed, or if reparative suture closure should fail, the patient is placed at risk of multiple organ failure. This article presents diagnostic approaches, emphasizing imaging modalities, and therapeutic strategies for three clinical scenarios of hollow viscus perforation: 1) acute appendicitis, 2) gastroduodenal peptic ulcer disease, and 3) trauma.

Abdominal Injuries↗

PubMed1997

Inositol 1,4,5-trisphosphate receptor expression in mammalian olfactory tissue.

Two cDNAs encoding inositol 1,4,5-trisphosphate (IP3) receptors were amplified from rat olfactory tissue, and both exhibited 100% sequence identity to the short (Segment II - ) variant of type I IP3 receptor. Type III IP3 receptor was also expressed in olfactory tissue. The distribution of IP3 receptors included the olfactory epithelium, lamina propria, and glandular tissue. These results demonstrate the co-expression of multiple IP3 receptor subtypes in olfactory cells, and suggest multiple functions for IP3 receptors in this tissue.

Animals↗

PubMed1997

Clinical evaluation of free PSA/total PSA (prostate-specific antigen) ratio in the diagnosis of prostate cancer.

The objective of this study was to evaluate the utility of the free/total prostate-specific antigen (PSA) ratio (per cent free PSA) in the diagnosis of prostate cancer. Serum total PSA and free PSA concentrations were measured in 156 patients with benign prostate hyperplasia (BPH) and 74 patients with prostate cancer using Hybritech Tandem immunoradiometric assays. Patients with prostate cancer had a significantly lower free/total PSA ratio than patients with BPH, although the distributions across study groups overlapped. In patients with a total PSA level between 4 micrograms/l and 25 micrograms/l, free/total PSA demonstrated better diagnostic utility than total PSA alone.

Diagnosis, Differential↗

PubMed1997

New cembranoid diterpenes and a geranylgeraniol derivative from the common Caribbean sea whip Eunicea succinea.

A recent collection and extraction of the common Caribbean sea whip Eunicea succinea from Puerto Rico has produced four previously undescribed representatives of the cembrane family of diterpenes (2, 3, 4, and 6). A new geranylgeraniol derivative, 8, was also isolated as a minor constituent. The chemical structures of the new compounds were carefully established by spectroscopic and chemical methods in addition to detailed NMR spectral comparisons with known cembranoid models from Eunicea.

Animals↗

PubMed1997

Prediction of left ventricular mass changes after renal transplantation by polymorphism of the angiotensin-converting-enzyme gene.

Cardiac complications are the main cause of death in renal transplant patients and left ventricular hypertrophy (LVH) may play a determinant role. An association between the insertion-deletion polymorphism of the angiotensin-converting enzyme (ACE) gene and LVH has been reported in adults. However, little is known about the genetic influence on left ventricular mass changes after renal transplantation, where unique environmental factors, such as cyclosporine A (CsA) and prednisone treatment concur. In fact, CsA treatment has recently been associated with the development of LVH. We prospectively determined the changes on cardiac structure and function, assessed by echocardiographic criteria, in 38 consecutive nondiabetic adults who received a cadaveric renal allograft. They were treated with cyclosporine and prednisone and maintained a good renal function during the follow-up. Echocardiographic studies (M-mode, 2-B and color flow Doppler) were performed without previous knowledge of the genetic typing, at the time of transplantation, and 6 and 12 months later. ACE alleles were typed using a PCR-based assay developed to ascertain the presence of an insertion (I)-deletion (D) polymorphism in intron 16 of the ACE gene. Patients with the so-called "unfavorable" DD genotype (N = 16) were compared with the ID or II genotypes (N = 22). The baseline left ventricular mass index was similar in patients with or without the unfavorable DD genotype (X +/- SE; 166.6 +/- 10.4 vs. 181.3 +/- 9 g/m2, respectively) and a similar proportion fulfilled the criteria of LVH (88% vs. 82%, respectively). The mean percent increase of the left ventricular mass index 12 months after renal transplantation was significantly higher in patients with the DD genotype compared to those with other genotypes (21.3 +/- 7.9 vs. -0.08 +/- 4.9%, respectively; P < 0.05). As a result, 94% of DD patients showed LVH at the end of the follow-up, while 68% of the ID or II patients had LVH (P < 0.05). In addition, the left ventricular ejection fraction significantly increased only in ID or II patients 12 months after transplantation with respect to baseline (ID/II patients, 70.4 +/- 1.5 vs. 63.7 +/- 1.8%; P < 0.05; DD patients, 68.3 +/- 2.1 vs. 63.3 +/- 2.9%). The deleterious effect of the DD genotype was independent of blood pressure, biochemical parameters, weight gain, and cumulative steroids dosages or cyclosporine levels. In conclusion, genetic factors determine the changes on cardiac structure and function after renal transplantation. The presence of the DD genotype of the ACE gene is a marker associated with an elevated risk of LVH in this population.

Adult↗

PubMed1997

Immunohistochemical study of a non-invasive canine thymoma: a case report.

We describe a case of canine thymoma in an 11-year-old pure-bred female Spanish Mastiff. On post-mortem examination a big mass was found in the thoracic cavity. Histologically the neoplastic parenchyma showed great structural variability; the principal findings included the presence of tumour cells forming cords or sheets, cystic formations, Hassall-corpuscle like squamous formations, and small or intermediate calibre vessels encircled by areas with eosinophilic material and lymphocytes. In order to determine the histogenesis of the thymic neoplasia we used immunohistochemical techniques specific for different markers: cytokeratins, vimentin, desmin and neuron specific enolase. A strong positive immunoreaction of tumour cells to wide spectrum cytokeratins confirmed the epithelial origin of the neoplasia.

Animals↗

PubMed1997

Structure and function of the CD94 C-type lectin receptor complex involved in recognition of HLA class I molecules.

A multigene family of immunoglobulin superfamily (Ig-SF) killer cell inhibitory receptors (KIRs) specifically recognize HLA class I molecules, while the interaction with H-2 products is mediated by members of the murine Ly49 C-type lectin family. A common structural feature of these receptors with inhibitory function is the presence of cytoplasmic immunoreceptor tyrosine-based inhibitory motifs (ITIMs) that couple them to SHP phosphatases. Strong support for the involvement of the CD94 C-type lectin receptor complex in NK cell-mediated recognition of Bw6+ HLA-B, HLA-A and HLA-C alleles has been obtained. The cloned CD94 molecule covalently assembles with at least two different glycoproteins (43 kDa and 39 kDa) to form functional receptors. NK cells inhibited upon HLA recognition express the CD94/p43 dimer, whose specificity for HLA molecules partially overlaps the Ig-SF receptor system. By contrast, NK clones bearing the homologous CD94/p39 receptor are triggered upon its ligation by CD94-specific mAbs. Remarkably, a set of Ig-SF receptors (p50) homologous to p58 KIRs also display an activating function. CD94-associated molecules belong to the NKG2 family of C-type lectins; the NKG2-A gene encodes for the p43 subunit, which contains cytoplasmic ITIMS. Expression of the different CD94 heterodimeric receptors will enable precise analysis of their putative interaction with HLA class I molecules.

Antigens, CD↗