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Biomedical subjects

R Estrada

Publications and source records attributed to R Estrada.

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

Sonographic appearance of mucocele of the appendix.

Mucocele of the appendix is an uncommon entity infrequently diagnosed prior to surgery or autopsy. Patients may be asymptomatic or present with a palpable right lower quadrant mass and/or pain. Barium enema findings are nonspecific and include nonfilling of the appendix and occasionally mass impression on the cecum. When visualized, calcification of the rim of a right lower quadrant mass may aid in diagnosis. The sonographic appearance in two cases is presented and compared with that in three other case reports in the literature, illustrating a spectrum of sonographic findings. Differential diagnosis is discussed.

Aged↗
PubMedDate not supplied

A randomized double-blind clinical trial of two antivenoms in patients bitten by Bothrops atrox in Colombia. The Regional Group on Antivenom Therapy Research (REGATHER).

A randomized double-blind clinical trial in 39 patients envenomed by Bothrops atrox in Antioquia and Chocó, Colombia, was performed to compare the efficacy and safety of 2 equine-derived antivenoms prepared at Instituto Clodomiro Picado, University of Costa Rica. Twenty patients received a monovalent anti-B. atrox antivenom (group A) and 19 patients were treated with a polyvalent (Crotalinae) antivenom (group B). Both antivenoms were equally efficient in the neutralization of the most relevant signs of envenoming (haemorrhage and blood clotting time alteration). Fourteen patients (36%) presented early adverse reactions to antivenoms and no significant difference between the 2 groups was observed. Urticaria (18%) was the most frequent early adverse reaction and there was no life-threatening anaphylactic reaction. Based on clinical criteria and serum venom levels, estimated by an enzyme immunoassay, 15 patients were classified into 2 groups: mild and moderate/severe envenoming. With the antivenom doses used in this study (3, 6 and 9 vials for mild, moderate and severe envenoming, respectively), both antivenoms were equally efficient in clearing serum venom levels within the first hour of treatment, and the levels remained below the lower limit of venom detection for 24 h. Antivenom concentration in serum remained high for up to 24 h after antivenom infusion, suggesting that an excess of antibody in relation to circulating antigen had been administered.

Adolescent↗
PubMedDate not supplied

[Inflammatory demyelinating chronic polyneuropathy: a contribution to the characterization of the disease].

INTRODUCTION AND OBJECTIVE: The chronic inflammatory demyelinating polyneuropathy (CIDP) is a controversial sickness. No doubt it is still a diagnosis without a strict nosologic delimitation until we acquire a greater knowledge about the underlying mechanisms, or whether a specific marker is found. We evaluated its clinical and laboratory findings, to contribute to its characterization in our environment. PATIENTS AND METHODS: We reviewed the records of 37 patients diagnosed with CIDP between 1986 and 1997. They were grouped in as to sex, age, beginning age (BA), evolution time, race, clinical form, symptoms, signs and evolutive profile. We analyzed the cytochemic and immunologic studies of cerebrospinal fluid (CSF) as well as sural nerve biopsy. RESULTS AND CONCLUSIONS: We demonstrated a predominance of BA between the fifth and sixth decades, and the presentation of a mixed polyradiculoneuropathy with motor predominance and a chronic progressive evolution. It was positively correlated with protein concentration levels in CSF, elevated in the 73.5% of the patients. There was an increase in the permeability of the blood brain barrier (BBB) in 50.8%, IgG intrathecal synthesis in 5.08 and oligoclonal bands in 8.8%. We found lost of myelin sheats in 90.6% of sural nerves and onion-bulbs formation in 60.5%, which demonstrated the high sensitivity of this study to confirm the diagnosis of demyelinating process as essential substrate in the illness.

Adolescent↗
PubMedDate not supplied

[Neuropathy of leprosy: characteristics of cases in 1962-1995].

INTRODUCTION: Neuropathy due to leprosy is the most frequent cause of peripheral nervous system disorders due to an infective agent, one of the commonest aetiologies of peripheral neuropathy, and also one of the few peripheral neuropathies which is curable. Hansen's disease, initially and predominantly involves the skin, so it is not usually seen by a neurologist; a neurologist sees cases which are difficult to diagnose and often after the condition has been ruled out by other doctors from other medical specialties. PATIENTS AND METHODS: In the National Institute of Neurology and Neurosurgery of La Habana, Cuba, 18 nerve biopsies were studied (during its history), that had been diagnosed as leprous neuropathy. We reviewed the clinical histories of all the patients admitted to this centre. The sample was characterized by: age, sex, neurological clinical picture, nerves most affected, skin lesions, electrophysiological studies and a description of the anatomopathological findings. RESULTS AND DISCUSSION: Most patients were male and all (100%) were adults of 'working age' (19-65 years). The most frequent neuropathic pattern was multiple mono-neuropathy (78%) and the quality, purely sensitive or mixed was predominantly sensitive (100%). The nerves most affected were the ulnar (10 patients) and median (6 patients). The most frequent skin lesions were anesthetic maculae. Anatomo-pathological study showed inflammatory infiltration in all patients and the bacillus was absent in only one case.

Adult↗
PubMedDate not supplied

[Electrophysiological characteristics of inflammatory demyelinating chronic polyneuropathy].

INTRODUCTION: The electrophysiological studies, specially nerve conduction studies (NCS) constitute one of the basic supports to obtain an early and accurate diagnosis to perform a successful treatment in the chronic inflammatory demyelinating polyneuropathy (CIDP). There is nevertheless, no definite consensus about which would be the most specific and sensitive electric variables in the illness. OBJECTIVE: To describe the NCS findings in a group of patients with this diagnosis, in order to contribute to its electrophysiological characterization. PATIENTS AND METHODS: We an analyzed the NCS on 37 patients diagnosed with CIDP. The NCS were done using standard techniques. These studies were assessed according to the reference values of a normative study on 90 healthy persons. We performed somatosensory evoked potentials (SSEP), visual (VEP) and brainstem auditory evoked potentials (BAEP) in 8 patients, and motor potentials (MP) by transcranial magnetic stimulation in 3. RESULTS: The registered values are presented in media comparison tables (cases/controls). The frequency of abnormalities in latencies (L), amplitudes, conduction velocity (CV) and the presence of partial blocks is analyzed. The affectation of the evoked potentials in some patients, demonstrated subclinical concomitant demyelinization of the central nervous system. CONCLUSIONS: The most sensitive electrophysiological parameters are the motor CV, the total duration and distal latencies, that gives these variables a confident value in the initial stages of the illness. The relative normality of conduction through the sural nerve, even in the presence of severe abnormalities of the median nerve constitutes a repetitive and specific pattern to this kind of illness.

Chronic Disease↗
PubMedDate not supplied

[Molecular studies in Cuban patients with progressive external ophthalmoplegia].

INTRODUCTION: The mitochondria, subcellular organelles which possess their own DNA (mtDNA), produce most of the energy, in the form of ATP, which is necessary for life. This mtDNA may have diverse molecular defects which have been associated with a great variety of clinical syndromes. Deletions in mtDNA are one of the common mutations in patients with mitochondrial myopathies, which in the great majority present with the common symptom of progressive external ophthalmoplegia. In this study we report our findings in eight Cuban families with suspected mitochondrial disease. OBJECTIVES: To characterize these patients from the molecular point of view, which would allow a preliminary understanding of the behavior of these deletions in Cuban patients. PATIENTS AND METHODS: We studied nine patients from eight Cuban families in whom mitochondrial encephalomyopathy was suspected. We analyzed the presence of ragged red fibres, the enzymatic activity of the mitochondrial respiratory chain and detection of mtDNA mutations. We used the technique of restriction length polymorphism analysis for detection of deletions. RESULTS: Histochemical studies showed the presence of COX negative ragged red fibres in seven of the patients studied. The enzymatic activity of the mitochondrial respiratory chain was normal in all the patients. We detected four patients with single deletions of mtDNA, and one with multiple deletions and of the patients had the A3243G mutation. CONCLUSIONS: With the methods used we were able to determine the presence of a mitochondrial disorder in seven of the eight families studied and deletions of mtDNA were detected as the cause of the illness in five. The disorder was always associated with progressive external ophthalmoplegia and COX negative ragged red fibres.

Adolescent↗
PubMedDate not supplied

The application of visual cell profiles in the study of premalignant atypias in sputum.

Because the diagnosis of squamous-cell carcinoma of the lung by routine cytologic screening of sputum is often inconclusive, our laboratory is studying the use of cytomorphologic profiles as a reliable diagnostic aid. This study reports the analysis of the profiles of 75 subjects, both cigarette-smoking volunteers and hospitalized patients suspect for lung cancer. Twenty-five of the subjects had been classified as having squamous metaplasia, 25 as having atypias and 25 as having squamous-cell carcinoma. Four slides were made for each subject, with 100 random fields viewed on each slide. The frequency of free alveolar macrophages, metaplastic squamous cells, epithelial atypical cells and malignant squamous cells were noted for each field. The results indicated that, although there were large differences between individual profiles within each diagnostic category, there were significant differences between the average profiles for each diagnostic category. Furthermore, although there were differences in cell frequencies from slide to slide and within slides, the differences were constant across diagnostic categories. The results are supportive of the progressive-atypia hypothesis for squamous-cell carcinoma of the lung and provide a baseline for comparison with subsequent individual profiles.

Carcinoma↗
PubMedDate not supplied

Visual cell profiles for quantitation of premalignant cells in sputum: a preliminary report.

Visual cell profiles were used to analyze the distribution of atypical bronchial cells in sputum specimens from cigarette-smoking volunteers, cigarette-smoking asbestos workers and cigarette-smoking uranium miners. The preliminary results of these sputum visual cell profile studies have demonstrated distinctive distributions of bronchial cell atypias in progressive patterns of squamous metaplasia, mild, moderate and severe atypias and carcinoma, similar to those the authors have previously reported using cell image analysis techniques to determine an atypia status index (ASI). The information gained from this study will be helpful in further validating this ASI and subsequently achieving the ultimate goal of employing cell image analysis for the rapid and precise identification of premalignant atypias in sputum.

Age Factors↗