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Biomedical subjects

L E Becker

Publications and source records attributed to L E Becker.

At least 217 records · Page 12Linked to original sources
PubMed1983

Primitive neuroectodermal tumors of the central nervous system.

Primitive neuroectodermal tumors are morphologically similar malignant tumors arising in intracranial and peripheral sites of the nervous system, showing varying degrees of cellular differentiation with a tendency to disseminate along cerebrospinal fluid pathways. They occur primarily in children and young adults. Under the designation primitive neuroectodermal tumors are included medulloblastomas and tumors that may differentiate in other directions, such as medulloepithelioma, neuroblastoma, polar spongioblastoma, pineoblastoma, ependymoblastoma, retinoblastoma, and olfactory neuroblastoma. From a practical, histologic point of view, these tumors are often indistinguishable from one another and are best thought of as primitive neuroectodermal tumors with or without differentiating features.

Animals↗
PubMed1983

Cutaneous zygomycosis in a patient with lymphoma.

A large variety of underlying conditions and diseases have been associated with zygomycosis. The most common ones include leukemia or lymphoma, burns, renal failure, septicemia, malnutrition, diabetes, cancer, chemotherapy, organ transplantation, and corticosteroid administration. While being ubiquitous in the environment and relatively harmless to healthy individuals, Zygomycetes can be fatal in the immunocompromised patient, especially if untreated or if treatment is delayed.

Child↗
PubMed1983

Intraventricular and subependymal haemorrhage in infants dying within 10 hours of birth.

A group of 103 infants was studied who were appropriate for gestational age (AGA), born at less than 36 weeks gestation, and died within 10 hours of birth. Intraventricular haemorrhage (IVH) had occurred in about one quarter of the extremely small, premature infants (28 weeks) within 5 hours of birth, but was rare in infants greater than 28 weeks gestation. The incidence of subependymal haemorrhage (SEH) was relatively high in babies who died within 5 hours of birth but IVH was more common in those who lived more than 5 hours. There was no relationship between the clinical events studied and the presence of IVH or SEH in the whole group of cases dying within 10 hours of birth, but the babies who died by 5 hours after birth had a high incidence of breech delivery and very low Apgar scores.

Brain↗
PubMed1983

Distribution of immunoreactive S-100 protein in pediatric brain tumors.

The distribution of S-100 proteins was examined in 98 pediatric brain neoplasms with rabbit antiserum to S-100 protein, utilizing the peroxidase-antiperoxidase (PAP) immunohistochemical technique. Positive cytoplasmic immunoreactivity was present in 22 of 24 astrocytomas, both oligodendrogliomas, eight of 13 ependymomas, all 11 choroid plexus tumors, all nine schwannomas, two of six meningiomas, and both meningeal melanomas. Mixed cytoplasmic immunoreactivity was present in both gangliogliomas, all seven craniopharyngiomas, and the only hemangioblastoma. No cytoplasmic immunoreactivity was found in primitive neuroectodermal tumors or germinoma. Nuclear immunoreactivity was present in some cases. Because of the broad spectrum of apparent immunoreactivity with S-100 antiserum, S-100 protein cannot be used as a specific marker of glial or Schwann cell tumors.

Astrocytoma↗
PubMed1983

Cerebral medulloepithelioma with bone, cartilage, and striated muscle. Light microscopic and immunohistochemical study.

A two-and-a-half-year-old girl had a cerebral medulloepithelioma with histologic evidence of ependymal, astroglial, oligodendroglial, and neuroblastic differentiation, as well as islands of cartilage and bone, and a microscopic focus of striated rhabdomyoblasts. Immunohistochemical staining for glial fibrillary acidic protein and S-100 protein with the peroxidase-antiperoxidase technique revealed positive staining in the various differentiating neural elements of the tumor. Mesectodermal differentiation, or the production by neuroectoderm of tissues usually considered to be mesodermal, is being increasingly recognized in the fields of embryology and tissue culture. Although this is the likely explanation for the composition of this tumor, other possibilities are considered as well.

Bone and Bones↗
PubMed1983

Medulloblastoma: clinical presentation and management. Experience at the hospital for sick children, toronto, 1950-1980.

The authors review the cases of 144 children with medulloblastoma treated between 1950 and 1980. Duration of time between onset of symptoms and initial treatment was less than 1 1/2 months in 51% of cases, and less than 3 months in 76%. The tumor was located in the cerebellar vermis in 93% of patients. Brainstem infiltration was noted in 32%. Classical medulloblastomas comprised 82% of the total number reviewed, and desmoplastic medulloblastomas 15%. The majority of desmoplastic medulloblastomas were found in the midline of the cerebellum and in patients under 10 years of age. The prognosis for patients with desmoplastic medulloblastomas was worse than that for children with classical medulloblastomas. Spontaneous hemorrhage associated with primary or recurrent medulloblastoma occurred in 5.6% of the patients. Supratentorial metastases were found in 14.6% of cases, spinal cord metastases in 12.5%, and systemic metastases in 9%. The overall 5-year survival rate was 47%, and the 10-year survival rate 42%. Extent of surgical excision proved to be a statistically significant prognostic factor. Two patients developed recurrence after the "period of risk" as defined by Collins' rule. Delayed complications of radiotherapy were found to be substantial. Intelligence quotient (IQ) testing on 16 survivors revealed verbal IQ, performance IQ, and full-scale IQ to be within the normal range in 11, seven, and nine cases, respectively. Two were retarded on all scores.

Adolescent↗
PubMed1983

S100 protein in human chordoma and human and rabbit notochord.

S100 protein is a protein that has been considered to be specific for tissues of neuroectodermal origin; however, recent studies have demonstrated the presence of S100 protein in mesodermal tissues. Using immunohistochemical methods, we found S100 protein in human chordomas and in human and rabbit notochordal tissue. Our findings suggest that S100 protein is present not only in neuroectodermal tissue but in mesodermal tissue, which develops in close proximity to neuroectoderm.

Animals↗
PubMed1982

Congenital muscular dystrophy: a clinicopathologic report of 24 cases.

Congenital muscular dystrophy (muscular dystrophy presenting from birth) with a wide spectrum of clinical severity is reported in 24 patients. Progression of symptoms was evident, leading to significant motor handicap in all patients and death in eight cases. Muscle enzyme studies did not always correlate with the severity of the disease. In six cases, initial muscle biopsy showed only minimal, nonspecific abnormalities; however, characteristic dystrophic changes were evident on repeat biopsies. Histochemical and electron microscopic studies did not show consistent changes, except type I predominance in a few cases. Evidently the condition is rarely, if ever, benign and the clinical course cannot be predicted from the initial presentation or early pathologic findings. Clinical, laboratory and pathologic characteristics are outlined for the diagnosis of this disorder.

Biopsy↗
PubMed1982

Myelination of the human vagus nerve from 24 weeks postconceptional age to adolescence.

Significant changes in respiratory reflexes occur with maturation. The vagus nerve, the pathway for the Hering-Breuer and irritant-receptor reflexes, was studied quantitatively in 33 infants and 5 adolescents. In the infants, total myelinated vagus fibers increased linearly (r m0.682, p less than 0.001) with postconceptional age (PCA), and by 40 weeks after conception, total counts were comparable to those of adolescent group. Counts of total myelinated vagus fibers in 16 term infants (greater than 41 weeks PCA) were comparable to those in the adolescent group (p less than 0.40), whereas 17 preterm infants (less than 38 weeks PCA) showed significantly fewer total myelinated vagus fibers than term or adolescent groups (p less than 0.001). Smaller-diameter (less than 2 micrometer) myelinated vagus fibers depended upon PCA in the preterm group (p less than 0.005), but were independent of PCA in the term group (p less than 0.5). Preterm infants have a higher percentage of small to total myelinated vagus fibers than term infants (p less than 0.1).

Adolescent↗
PubMed1982

Retardation of neuronal maturation in premature infants compared with term infants of the same postconceptional age.

Neuronal morphologic development and the number of soma and spines in the visual cortex were investigated. Ten premature infants surviving at least three weeks were compared with control infants who had been born at term gestation and had the same postconceptional age. In six cases of sudden infant death syndrome, bronchopulmonary dysplasia, or patent ductus arteriosus, neuronal development was similar to that in the control cases. The persistence of immature neurons in two of the remaining four cases suggested a developmental neuronal delay or arrest.

Bronchopulmonary Dysplasia↗