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S Martinez

Publications and source records attributed to S Martinez.

At least 91 records · Page 5Linked to original sources
PubMed1995

Concordance in diagnosis of diabetic retinopathy by fundus photography between retina specialists and a standardized reading center. Mexico City Diabetes Study Retinopathy Group.

Proper detection and adequate laser therapy of diabetic retinopathy (DR) using guidelines established by landmark studies is important to prevent blindness. We analyzed the agreement between diagnostic classification of DR as determined by certified retina specialists compared with standardized readings of fundus photographs performed by the Fundus Photograph Reading Center (FPRC) of the University of Wisconsin. Color fundus stereophotographs of seven standard fields of each eye of 15 diabetics were sent to FPRC and to 11 retina specialists practicing in Mexico City and representing the major health care institutions. These centers are sites for training programs in ophthalmology. In addition, leading specialists in private practice were invited to participate. Their diagnostic criteria were surveyed. Information was collected using a specially designed form on which the investigator entered his/her diagnostic classification using his/her clinical judgment. Mean overall percent agreement was 74%. Kappa statistic, which corrects for chance agreement, was between 0.29-0.87 with a mean of 0.53. Weighted kappa measuring level of disagreement was between 0.34-0.90, mean 0.57. Data were analyzed separately for macular edema and for this end point the weighted kappa statistic was 0.68. Based on conventional interpretation of the kappa statistic, these mean values are in the range of fair agreement. However, since there is a significant discrepancy in the concordance level observed, there is a need for promoting further applications of internationally accepted diagnostic criteria to assure optimal therapy.

Adult↗
PubMed1995

Oligodendrocytes originate in a restricted zone of the embryonic ventral neural tube defined by DM-20 mRNA expression.

Products of the PLP gene, proteolipid protein and its isoform DM-20, are the most abundant proteins in CNS myelin, and are markers of the oligodendrocyte, the myelin-forming cell in the CNS. The DM-20 transcript has previously been reported to be expressed in newborn oligodendrocyte progenitor cells and during embryonic development. We have therefore used a DM-20 cRNA probe to follow, by in situ hybridization, the oligodendrocyte lineage during embryonic development. DM-20-expressing cells were first detected at E9.5 in the ventricular germinal layer of the laterobasal plate of the diencephalon. At E14.5, DM-20+ cells had largely disappeared from the diencephalic ventricular germinal layer and had colonized the ventral mantle layer at the posterior part of the basal diencephalon. Between E17.5 and P1, the number of DM-20+ cells increased and progressively invaded the major white matter tracts. In the hindbrain, DM-20+ cells appeared at E12.5 in the caudal part of the rhombencephalon, and at E14.5 all along the ventral spinal cord. Between E14.5 and P1, DM-20+ cells progressively colonized, first ventrally then dorsally, all the spinal cord and more extensively the white matter tracts. At E14.5, a large gap separated, rostrally, the medullary columns from the mantle layer cells in the prosencephalon, suggesting that oligodendrocytes in the mid- and forebrain originate from a different pool of precursors than in the rhombencephalon and the spinal cord. Together, these observations suggest that expression of the DM-20 transcript is an early marker of commitment to the oligodendrocyte lineage, and that oligodendrocyte precursors originate in a ventrally restricted region.

Animals↗
PubMed1994

SR141716A, a potent and selective antagonist of the brain cannabinoid receptor.

SR141716A is the first selective and orally active antagonist of the brain cannabinoid receptor. This compound displays nanomolar affinity for the central cannabinoid receptor but is not active on the peripheral cannabinoid receptor. In vitro, SR141716A antagonises the inhibitory effects of cannabinoid receptor agonists on both mouse vas deferens contractions and adenylyl cyclase activity in rat brain membranes. After intraperitoneal or oral administration SR141716A antagonises classical pharmacological and behavioural effects of cannabinoid receptor agonists. This compound should prove to be a powerful tool for investigating the in vivo functions of the anandamide/cannabinoid system.

Animals↗
PubMed1994

Cytologic study of renal angiomyolipoma by fine-needle aspiration biopsy: report of four cases.

Four cases of renal angiomyolipoma (AML) diagnosed by fine-needle aspiration biopsy (FNAB) are reported. One case was associated with the clinical complex of tuberous sclerosis. The tumors were solitary in two cases and multiple and bilateral in the fourth. The cytologic features of the four cases were similar to those described in the literature: smooth muscle cells intermingled with mature fat cells and blood vessels, together with a lipoidic background. These tumors are currently considered benign although they may present characteristics accepted as criteria of malignancy in other tumors: pleomorphism and atypical smooth muscle cells, vascular invasion, capsular rupture, and lymphatic involvement. We conclude that it is important and possible to establish preoperative cytologic diagnosis, since treatment of these tumors is conservative and obviates aggressive nephrectomy.

Adolescent↗
PubMed1994

Spontaneous bovine respiratory syncytial virus infection in goats: pathological findings.

This paper presents the results of a study of eight cases of natural bovine respiratory syncytial virus (BRSV) infection in a herd of 50 Murciana kids from a intensive goat-farm in Spain. Clinical and pathological analysis confirmed the existence of natural BRSV infection in eight kids. In two of the eight animals there was also evidence of concurrent infection with P. haemolytica A.

Animals↗
PubMed1994

Does radiographic osteoarthritis correlate with flexibility of the lumbar spine?

OBJECTIVES: To examine the association between radiographic lumbosacral (LS) osteoarthritis (OA) and lumbar flexibility in elders without back pain or known spinal pathology and to develop a reliable grading system for osteoarthritis of the lumbosacral spine. DESIGN: Cross-sectional study. SETTING: Durham VA and Duke University Medical Center Department of Radiology. PARTICIPANTS: 35 volunteers aged 64-90 (nursing home residents and community dwellers). Exclusion criteria were known spinal pathology, back pain, inability to stand independently for 1 minute, and > 150% of ideal body weight. INTERVENTIONS: All subjects underwent LS spine radiographs and flexibility measures (forward flexion, extension, lateral flexion, and axial rotation). MAIN OUTCOME MEASURES: Reliability of ordinal OA X-ray grading system, tested using intraclass correlations (ICCs); stability of flexibility measures, using ICCs; and association of disc or facet summary scores (sum of all levels, T12 thru S1) with flexibility measures, using Pearson correlations. RESULTS: ICCs for interest flexibility measures ranged from 0.72 to 0.94. ICCs for interobserver X-ray scores were 0.85 for facet disease and 0.93 for disc disease. The correlation of facet disease with forward lumbar flexion was 0.29. The correlation of disc disease with flexibility showed modest correlation for forward (r = 0.34), right lateral (r = 0.36), and left lateral (r = 0.35) flexion. None of the correlations was influenced by age. CONCLUSIONS: We have developed a reliable radiographic scoring instrument for assessing radiographic OA of the LS spine. It appears that painless LS disc OA is one factor that influences spinal motion.

Aged↗
PubMed1993

Leishmania lymphadenitis diagnosed by fine-needle aspiration biopsy.

A case of Leishmania lymphadenitis which presented clinically as an isolated left laterocervical lymph node is described. Diagnosis was made by fine-needle aspiration biopsy (FNAB), as in other cases previously reported. The material obtained yielded abundant histiocytes, multinucleated giant cells, and epithelioid microgranulomas with Leishman-Donovan pathognomic bodies in the cytoplasm of cells, together with free forms of the parasite. This paper comments on the main differential diagnoses to be considered in our region when faced with granulomatous adenitis and the role of FNAB in the identification of this parasite in endemic areas.

Adult↗
PubMed1993

Association of osteoporotic vertebral compression fractures with impaired functional status.

PURPOSE: To determine if vertebral compression fractures in elderly women were associated with impairments in physical, functional, and psychosocial performance. SUBJECTS AND METHODS: Ten white women with confirmed vertebral compression fractures were age- and race-matched with 10 control subjects without fractures in a case-control design. All subjects invited to participate in this study were patients of the Geriatrics Division of the Department of Medicine at Duke University Medical Center. All study participants lived either in the community or in the independent-living sections of local retirement communities in and around Durham, NC. Subjects with fractures (mean age = 81.9 years, SD = 5.9 years) had two or more vertebral compression fractures in their medical records, whereas control subjects (mean age = 79.6 years, SD = 6.5 years) had no history of vertebral fractures. Spinal radiographs of all women confirmed group assignment. Physical, functional, and psychosocial performances were evaluated. Physical performance was assessed by measurements of maximal trunk extension torque and thoracic and lumbar spinal motion in the sagittal plane, functional reach, mobility skills, 10-ft timed walk, and 6-minute walk test. Thoracic and lumbar spinal configurations were also determined. Functional performance was assessed using the Functional Status Index. Psychosocial performance was assessed with the following scales: Hopkins Symptom Checklist 90 Revised, Rosenberg Self-Esteem Scale, West Haven-Yale Pain Inventory, Beck Depression Inventory, and single-item health-belief questions. RESULTS: Control subjects were not significantly different from patients with fractures in age, weight, number of current illnesses, number of prescribed medications, number of pain medications, ratings of lumbar spine degenerative disc disease, or lumbar spine facet joint arthritis. Activity levels and exercise participation were similar in both groups. Control subjects had no vertebral fractures, whereas fracture subjects had 4.2 +/- 2.6 fractures (range: 2 to 10). Thoracic kyphosis was increased and lumbar lordosis was reduced in fracture subjects. Fracture subjects had reduced maximal trunk extension torque, thoracic and lumbar spine sagittal plane motion, functional reach, mobility skills, and 6-minute walk test. The Functional Status Index showed reduced levels of functional performance in fracture subjects compared with controls with increased levels of assistance, pain with activity, and difficulty in activities. Psychosocial performance was limited in fracture subjects with increased psychiatric symptoms, increased pain, and greater perception of problems caused by health. CONCLUSION: Vertebral compression fractures are associated with significant performance impairments in physical, functional, and psychosocial domains in older women.

Activities of Daily Living↗
PubMed1993

The immunologic response to experimental infection with bovine respiratory syncytial virus in lambs.

An experimental model was designed to study the humoral immune response in lambs experimentally infected with bovine respiratory syncytial virus (BRSV), 25 Merino lambs of both sexes, with a live weight of 17 +/- 3 kg, received an intratracheal inoculation of 20 ml. saline solution containing 1.26 x 10(6) TCID50 BRSV (strain NMK-7) per ml. Blood samples for serological analysis were collected from the jugular vein of the animals on days 0, 1, 3, 5, 7, 9, 11 and 15 post inoculation. Serum proteins were determined by electrophoresis, and a qualitative and quantitative analysis of immunoglobulins (Ig) was carried out using immunoelectrophoresis (IE) and light nephelometry, respectively. Serum anti-BRSV antibody levels were tested by enzyme-linked immunoabsorbent assay (ELISA). Lambs were necropsied 1, 3, 7, 11 and 15 postinoculation days (p.i.d.), and samples were taken for immunohistochemical analysis. IgA, IgG and IgM were labelled on paraffin-embedded lung sections using an avidin-biotin-peroxidase complex. Results reflected an increase in gamma fractions in experimental animals with respect to controls. IE analysis of these sera revealed a polyclonal increase in immunoglobulins. Nephelometric examination showed an increase in serum IgA, IgG an IgM levels up to 7 p.i.d., coinciding closely with high titres for humoral virus antibodies. After 9 p.i.d., titres and immunoglobulin levels both fell. Immunoglobulin labelling in formol-fixed and paraffin-embedded lung tissue samples detected IgG and IgA, mainly in bronchial, bronchiolar and alveolar epithelia. IgM, however, was not detected in the lungs of infected animals.

Animals↗
PubMed1993

The mouse homeodomain protein Phox2 regulates Ncam promoter activity in concert with Cux/CDP and is a putative determinant of neurotransmitter phenotype.

Transcriptional regulation of the gene encoding the cell adhesion receptor NCAM (neural cell adhesion molecule), a putative effector molecule of a variety of morphogenetic events, is likely to involve important regulators of morphogenesis. Here we identify two mouse homeodomain proteins that bind to an upstream regulatory element in the Ncam promoter: Cux, related to Drosophila cut and human CDP, and Phox2, a novel protein with a homeodomain related to that of the Drosophila paired gene. In transient transfection experiments, Cux was found to be a strong inhibitor of Ncam promoter activity, and this inhibition could be relieved by simultaneously overexpressing Phox2. These results suggest that the Ncam gene might be a direct target of homeodomain proteins and provide a striking example of regulatory cross-talk between homeodomain proteins of different classes. Whereas the expression pattern of Cux/CDP includes many NCAM-negative sites, Phox2 expression was restricted to cells also expressing Ncam or their progenitors. The localisation data thus strongly reinforce the notion that Phox2 plays a role in transcriptional activation of Ncam in Phox2-positive cell types. In the peripheral nervous system, Phox2 was strongly expressed in all ganglia of the autonomic nervous system and more weakly in some cranial sensory ganglia, but not in the sensory ganglia of the trunk. Phox2 transcripts were detected in the primordia of sympathetic ganglia as soon as they form. Phox2 expression in the brain was confined to spatially restricted domains in the hindbrain, which correspond to the noradrenergic and adrenergic nuclei once they are identifiable. All Phox2-expressing components of the peripheral nervous system are at least transiently adrenergic or noradrenergic. In the developing brain, Phox2 was expressed at all known locations of (nor)adrenergic neurones and of their precursors. These results suggest that Phox2, in addition to regulating the NCAM gene, may be part of the regulatory cascade that controls the differentiation of neurons towards this neurotransmitter phenotype.

Amino Acid Sequence↗
PubMed1993

Effect of "standing" on spasticity, contracture, and osteoporosis in paralyzed males.

The effect of "standing" in a frame on spasticity (clinical assessment and H-reflex), contracture (lower extremity joint range of motion), and osteoporosis (dual photon absorptiometry) was studied in six paralyzed males (mean age 49 yr) who had been confined to wheelchairs for an average of 19 years. Standing time averaged 144 hours over a mean of 135 days. Clinical Assessment measured reflexes, tone, and clonus in the legs. Results revealed no important differences between initial and final scores for clinical assessment and joint range of motion. In three subjects for whom H-reflexes were found, latency and amplitude were not altered by "standing." Bone density was normal in the lumbar spine but significantly reduced in the femoral neck. "Standing" did not modify the bone density in any site. A follow-up interview revealed that 67% of subjects continued to "stand" and felt healthier because of it. In summary, "standing" had no ill effects, did not alter measured variables, and had a positive psychological impact.

Absorptiometry, Photon↗
PubMed1992

Allopurinol in the treatment of American cutaneous leishmaniasis.

BACKGROUND: Pentavalent antimony, the generally accepted treatment for leishmaniasis, is given parenterally, and it is expensive and not readily available in developing countries. An inexpensive, orally administered compound would be a substantial advance in treatment. Previous studies in vitro have shown synergism between allopurinol and pentavalent antimony in tissue-culture systems. We designed this clinical study to determine whether synergism could be demonstrated in patients. METHODS: We performed a randomized, controlled study of the efficacy of allopurinol plus meglumine antimoniate (Glucantime), as compared with meglumine antimoniate alone, in patients with cutaneous leishmaniasis, who were recruited from a village in southeastern Colombia. In addition, those who declined injections were treated with allopurinol alone, and those who declined any treatment were considered controls. All the patients were followed for one year after the completion of treatment. Lesions that healed completely at three months and remained healed during follow-up were considered to be cured. RESULTS: The cure rate for patients treated with meglumine antimoniate was 36 percent; the addition of allopurinol increased the rate to 74 percent (P less than 0.001). Treatment with allopurinol alone yielded a cure rate of 80 percent (P less than 0.001). There were no cures among the untreated patients. There was no significant difference between the cure rate with allopurinol plus meglumine antimoniate and that with allopurinol alone. No major toxic effects were observed. CONCLUSIONS: For the treatment of American cutaneous leishmaniasis, the combination of allopurinol and meglumine antimoniate is significantly more effective than meglumine antimoniate alone, probably because of the efficacy of allopurinol alone, which appears to be as good as the combination.

Adolescent↗
PubMed1992

Cervical spondylolysis.

The term cervical spondylolysis describes a long-standing, perhaps congenital defect of the pars interarticularis of a cervical vertebra. We report 10 new cases of cervical spondylolysis and review the literature. All patients in this report were treated nonoperatively with subsequent symptomatic improvement. Cervical spondylolysis must be differentiated from its traumatic counterparts radiographically. Characteristic radiographic findings include well-corticated margins at the defect, a characteristic "bow tie" deformity, and ipsilateral dysplastic facets. Compensatory hypertrophic changes of the adjacent articular processes, spina bifida, and spondylolisthesis are frequently, but not always, seen in conjunction with cervical spondylolysis. The vast majority of patients with radiographically proven cervical spondylolysis can be treated confidently with conservative measures. Surgical intervention should be reserved for those who fail nonoperative management or who exhibit neurologic compromise referable to an unstable spondylolytic defect.

Adolescent↗