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Biomedical subjects

J Navarro

Publications and source records attributed to J Navarro.

At least 343 records · Page 19Linked to original sources

Expression of a possible constitutional "hot spot" in sperm chromosomes of a patient treated for Wilms' tumor.

Sperm chromosomes were studied in a man who was treated for Wilms' tumor with radiotherapy (RT) and chemotherapy (CT) 18 years ago. Human pronuclear sperm chromosomes were obtained after penetration of zona-free hamster eggs. Eighty-nine sperm chromosome complements were analyzed; 12.4% of them showed structural anomalies. This percentage was statistically different from the one found in our laboratory for controls (p less than 0.05). Five of eleven structurally abnormal metaphases had the same aberration: fission of chromosome #1 with the breakpoint at or near the centromere. Breaks and rearrangements of chromosome #1, often involving the centromere region, are among the most frequent anomalies found in Wilms' tumor cells.

Adult↗

Synaptonemal complex studies in the male.

Observations in synaptemal complexes in men carrying structural or numerical chromosomal anomalies are reviewed. Chromosome pairing in patients with extra chromosomes, Robertsonian translocations, reciprocal translocations and pericentric inversions is described. Synaptic anomalies in patients with abnormal seminograms, homosynapsis, asynapsis and heterosynapsis and other pairing abnormalities are also discussed.

Chromosome Aberrations↗

Study of human sperm chromosomes by sequential transmission and scanning electron microscopy.

We describe a method of observing human sperm metaphases by sequential transmission and scanning electron microscopy. This permits the analysis of ultrastructural aspects of sperm chromosomes and allows the relationship between ultrastructure, heterochromatin condensation, and the behaviour and staining properties of sperm chromosomes and heterochromatic regions to be determined.

Centromere↗

International dermatosurgery: reconstructive treatment of the vulva--a new procedure: experience on 23 cases over 4 years.

The postvulvectomy reconstruction caused the authors diverse problems in the first three operations. The use of a bipedicle advancement flap obtained from the anterointernal region of the thigh, modified depending on the extension of the vulvectomy and the elasticity of the skin allow us to suggest the use of this technique due to its safeness, the facility with which it is carried out, and reduction of the hospital stay, as this makes the method socially economical.

Atrophy↗

Hemodynamic changes with enalapril in pulmonary arterial hypertension secondary to congenital heart disease.

Enalapril was used to treat five patients with pulmonary arterial hypertension secondary to congenital cardiopathy, three with ventricular septal defect, one with arterial septal defect, and one with patent ductus arteriosus. The dose of enalapril was 20 mg/day. All patients underwent pretreatment and posttreatment cardiac catheterization. It was concluded that enalapril may be a useful drug in the treatment of pulmonary arterial hypertension secondary to congenital cardiopathy.

Adult↗

[Acute pancreatitis. Neurovascular and microcirculatory changes. Pathogenic and therapeutic study].

A group of 159 dogs divided in 8 sub-groups were studied, in regard to pancreatitis, the purpose of the study was to investigate the participation of the automatic nervous system in the course of acute pancreatitis. The procedures and the results were as follows: 1. Pancreatitis was induced in two forms: a) Injection of gallbladder bile, from the same animal to the pancreatic duct. b) Blind duodenal loop with exclusion of the distal duodenum through the pylorus. In both cases acute pancreatitis was obtained. Fat necrosis was predominant in type a, and hemorrhagic lesions in type b. 2. The anesthetic block of the celiac plexus controlled the pain and shock. The animals were in good general conditions but there were no changes in the pathological process of the pancreas. The same results were noted in surgical resections of splanchnic trunks. 3. When the surgical resections of splanchnic nerves was followed by a waiting period of 20 days from the production of pancreatitis there were no changes in the gland. 5. Vagotomy previous to pancreatitis does not have protector effects in the induction of pancreatitis. 6. Continuous perfusion of E.V. novocaine was of extreme utility. The animals remained without pain and the process remained stable when it was given in the initial face of edema. 7. The enzyme inhibitor (Trasylol) given in the first 24 hs. does not prove to be valuable. Due to the fermentative derangement the condition of the animals was better maintained in relation to the comparative animals.

Acute Disease↗

[Effects of loperamide on the fecal flora in children in severe diarrheas].

Loperamide has been recently indicated in the management of infants with severe protracted diarrhea. The purpose of this study was to determine the effect of loperamide on fecal flora in severe protracted diarrheas. 19 children aged 1 to 36 months, with severe protracted diarrhea were studied: 14 received loperamide (0.5 mg/kg/d) and 5 were without loperamide treatment. Criteria analysed were: clinical tolerance (vomiting and abdominal distention); efficacy (number of stools, transit time and Na+/K+ in stools) and effect on fecal flora, with differential qualitative and quantitative analysis method (complete identification and counts of aerobic and strict anaerobic bacteria in fresh fecal samples before and 4 to 8 days after the beginning of loperamide). Parenteral and/or oral alimentation remain constant during the study. Results show a rapid (24 h) efficacy in 9/14. Although important changes in specific fecal flora counts was noticed for streptococcus D and Proteus as compared to five controls, no bacterial overgrowth appeared or was increased during loperamide treatment.

Child, Preschool↗

[Effect of loperamide on fecal flora of children with severe prolonged diarrhea].

Loperamide has recently been proposed in the management of infants with severe protracted diarrhea. The purpose of this study was to determine the effect of loperamide (0.5 mg/kg/d) on fecal flora in 19 cases of severe protracted diarrhea. Criteria analysed were: clinical tolerance (vomiting and abdominal distension) and efficacy (number of stools, transit time and Na/k in stools); complete identification and counts of aerobic and strict anaerobic bacteria in fresh stools before and 4 to 8 days after the beginning of loperamide. Parental and/or oral alimentation remained unchanged during the entire study. Clinical resolution of diarrhea was rapid (less than 24 h) in 9 of 14 patients. In 2 cases ileus was observed and resolved when loperamide was discontinued. Although important changes in specific fecal flora counts was noticed for streptococcus D and proteus as compared to 5 controls, no bacterial overgrowth appeared or was worsened during loperamide treatment.

Child, Preschool↗

[The association of megaesophagus, Binder's syndrome and dysautonomia: a new neurocristopathy].

A case of esophageal achalasia is reported in a 12 year-old child. Nasal hypoplasia (Binder syndrome) and dysautonomia were associated. This may be explained by the common embryologic origin (neural crests) of nasal bud, autonomic nervous system and digestive intramural neurons. Such a neurocristopathy suggests exploration of the autonomic nervous system in cases of esophageal achalasia.

Autonomic Nervous System Diseases↗

G-banding of human sperm chromosomes.

G-banded human sperm chromosomes are routinely obtained in our laboratory using a modification of the method described by Martin et al. (1982). The study of banded sperm chromosomes is essential for the genetic counseling of male carriers of balanced chromosome rearrangements.

Chromosome Banding↗

Meiotic chromosome studies and synaptonemal complex analyses by light and electron microscopy in 47 infertile or sterile males.

Mitotic and meiotic chromosome studies and synaptonemal complex analyses by light and electron microscopy have been carried out in a selected series of 47 infertile or sterile males with highly abnormal seminograms, affecting the number of spermatozoa, their morphology and/or motility. In 46 cases, the karyotype was 46,XY. One patient had a 13/14 translocation. With the exception of the patient with a 13/14 translocation, and three patients with desynapsis (8.5%), all other cases showed either normal or absent metaphase I figures. However, synaptonemal complex analysis by light and electron microscopy demonstrated the presence of pairing anomalies (desynapsis, fragmented or irregular synaptonemal complexes) in 31.9% of the patients studied. The total number of synaptic anomalies observed (40.4%) is higher than in a former light microscopy study of 111 infertile or sterile patients (28.8%) probably because the higher resolution of the electron microscope permits the characterization of some anomalies that cannot be detected with the light microscope. The electron microscope should therefore be used in all cases in which the light microscope provides doubtful results.

Chromosomes, Human↗

Dihydropyridine [methyl-3H]PN 200-110 binding and myogenesis in intact muscle cells in vitro.

The radioligand dihydropyridine [methyl-3H]PN 200-110 binds to contracting myotubes in culture derived from chick embryo pectoralis muscle. [methyl-3H]PN 200-110 binds specifically to high-affinity sites, with nonspecific binding only between 15 and 30% of the total binding. A Scatchard plot of the specific binding revealed a single high-affinity binding site with a KD (dissociation constant) of 0.5 nM +/- 0.2 nM and Bmax (number of binding sites) of 100 fmol/10(6) nuclei. We employed this sensitive assay to probe the appearance of high-affinity [methyl-3H]PN 200-110 binding sites during myogenesis. The time course of appearance of high-affinity binding sites lags behind that of fusion. Low-calcium media prevented the differentiation of myoblasts and blocked the appearance of high-affinity sites. Chelation of intracellular calcium before or after fusion of myoblasts with the calcium indicator Quin 2 prevented the appearance of dihydropyridine binding sites. These findings are consistent with the view that the expression of dihydropyridine receptors is modulated by the intracellular calcium.

Aminoquinolines↗