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Biomedical subjects

L E Becker

Publications and source records attributed to L E Becker.

At least 145 records · Page 8Linked to original sources
PubMed1991

Puppet-like syndrome of Angelman: a pathologic and neurochemical study.

We present the first pathologic descriptions of the puppet-like syndrome of Angelman based on autopsy studies of a 21-year-old woman. The noteworthy findings were a small brain with mild cerebral atrophy but normal gyral development. There was marked cerebellar atrophy with loss of Purkinje and granule cells and extensive Bergmann's gliosis. Study of dendrite morphology using Golgi impregnations of the visual cortex revealed a prominent decrease in dendritic arborization of layer 3 and layer 5 pyramidal neurons. Quantitative Golgi analysis also revealed a significant decrease in the numbers of dendritic spines in apical layer 3 dendrites and both apical and basal layer 5 dendrites. Neurochemical studies of frozen brain tissue demonstrated markedly reduced gamma-aminobutyric acid content in the cerebellar cortex, as well as elevated glutamate content in the frontal and occipital cortices. Although there are no definite morphologic correlates of many of the clinical signs, the pronounced dendritic pathology and neurochemical abnormalities in cerebral cortex may provide a physiologic basis for mental retardation.

Adult↗
PubMed1991

Intracranial germ-cell tumors in children.

All patients with confirmed intracranial germ-cell tumors treated at the Hospital of Sick Children during the period January, 1952, to December, 1989, were reviewed. Of the 51 tumors reviewed, 16 were located in the suprasellar region, 32 in the pineal region, and three in both the pineal and the suprasellar regions. Forty-nine patients underwent surgical resection which was total in seven and partial in 20, and consisted of a biopsy in 22. Two patients were managed on the basis of serum and cerebrospinal fluid markers. Surgical tools such as the operating microscope, the ultrasonic surgical aspirator, and the laser beam allowed safe debulking and removal of the deep-seated tumors in the pineal region. There were no operative deaths in the 36 patients treated since 1972, who included 23 with pineal tumors. Twenty-five patients with germinomas received radiotherapy and had a 5-year survival rate of 85.1%. Thirteen patients with non-germinoma germ-cell tumors received radiotherapy and had a 5-year survival rate of 45.5%. On the basis of this review, the authors recommend resection of pineal and suprasellar germ-cell tumors in order to firmly establish an accurate histological diagnosis to guide the extent of adjuvant therapy. In the case of a pure germinoma without evidence of dissemination, adjuvant therapy consists only of local radiotherapy. On the other hand, for malignant non-germinoma germ-cell tumors, adjuvant therapy must include chemotherapy as well as craniospinal axis radiotherapy.

Adolescent↗
PubMed1991

Transthyretin immunoreactivity in choroid plexus neoplasms and brain metastases.

Although choroid plexus papillomas (CPP) and primary choroid plexus carcinomas (CPC) are rare neoplasms of the central nervous system, they have been the subject of a number of immunohistochemical studies. To date, no unique or specific marker for these neoplasms has been found, however. Normal choroid plexus is a major site of transthyretin (TTR) synthesis, and recently this protein has been proposed as a possible specific marker of choroid plexus differentiation in tumors. In this study, we performed immunohistochemistry for TTR on 13 choroid plexus tumors (six CPP and seven CPC) and on 23 carcinomas metastatic to the brain, four of which had a papillary architecture. We also included four ovarian teratomas that contained choroid plexus elements. Two of the CPP had diffuse staining for TTR, while the four others stained only focally. Five of the CPC stained only focally and less intensely than the control, while one case was negative. Only one CPC stained as strongly and diffusely as normal choroid plexus. Two of the papillary and six of the nonpapillary metastases had focal staining similar to that seen in the five focally positive CPC. The choroid plexus elements of the ovarian teratomas stained as strongly as the positive control. These findings indicate that TTR immunoreactivity is not restricted to primary choroid plexus tumors. Furthermore, most choroid plexus carcinomas stain only weakly or not at all. This limits the usefulness of TTR immunohistochemistry in the diagnosis of primary choroid plexus neoplasms and in the distinction of CPC from metastatic carcinoma.

Adenocarcinoma↗
PubMed1990

Dendritic arborization in the human fetus and infant with the trisomy 18 syndrome.

Dendritic arborization patterns of visual cortical neurons in four cases of trisomy 18 syndrome were compared with those in 8 neurologically asymptomatic age-matched controls. The trisomy cases included a 20-week-old fetus, a term infant, a 3-month-old infant, and 6-month-old infant. Quantitative Golgi analysis showed a decrease in the mean total dendritic length of apical dendrites in layer 5 pyramidal neurons in the term infant with trisomy 18. In layer 3, an attenuated dendritic tree was observed in the earlier age groups with increased dendritic extent at 6 months. Although not conclusive, due to the small number of subjects, this preliminary study showed definitive dendritic abnormalities in the trisomy 18 syndrome.

Chromosomes, Human, Pair 18↗
PubMed1990

Neural maturational delay as a link in the chain of events leading to SIDS.

Although numerous etiological or triggering factors have been suggested in sudden infant death syndrome (SIDS), the underlying mechanism of death is ultimately cardiac and/or respiratory in nature. As there is no evidence of lung or heart abnormalities, attention has focussed on the neural control of respiration and cardiac function. It is important to appreciate the methodological limitations involved in utilizing autopsy material and the criteria for selection of appropriate controls. This report reviews the pathological evidence for developmental delay in SIDS emphasizing delay of neural maturation of both myelination and synapses. Other abnormalities of the nervous system apparently associated with hypoxia-ischemia such as brainstem astrogliosis are also discussed. The occurrence of SIDS at a precise age together with our preliminary studies indicate that neural development delay is an important link in the chain of events leading to SIDS.

Heart↗
PubMed1990

Dendritic development of motor neurons in the cervical anterior horn and hypoglossal nucleus of normal infants and victims of sudden infant death syndrome.

Morphometric Golgi methods were used to study dendritic development of neurons in the cervical ventral and dorsal horns and the hypoglossal nucleus of 8 victims of sudden infant death syndrome and 20 age-matched control infants. The dendrites and spines of these neurons proliferated rapidly until 28 weeks gestation, then increased slowly until shortly after birth. Dendritic spine density of motor neurons in the cervical anterior horn and hypoglossal nucleus of victims of sudden infant death syndrome was similar to that of the controls. Thus, the delayed maturation of dendritic spines seen in the reticular formation and vagal nuclei is not present in motor neurons of the cervical anterior horn and hypoglossal nucleus.

Dendrites↗
PubMed1990

Assessment of growth in sudden infant death syndrome.

Autopsy reports from 208 cases of sudden infant death syndrome (SIDS) were reviewed and divided into three groups: group 1, term infants without infection; group 2, term infants with mild infection, and group 3, premature infants. The brain weights of these children were matched by age and body length, separately for males and females, with reference values and a group of 53 children born at term who died from conditions that did not affect the central nervous system. The brains of children in groups 1 and 2 were heavier than reference values when matched by age and body length. The differences between group 1 and reference values tended to increase with age; however, when matched by body length, this tendency was no longer observed. Body lengths of SIDS cases at death were also greater than reference values. There was no difference between brain weights of children in groups 1 and 2. These data suggest that the enlarged brains were present from birth rather than the result of disproportionate postnatal growth. The cause of increased brain size in SIDS cases is unknown, as is its possible role in the events leading to sudden death.

Brain↗
PubMed1990

Infratentorial ependymomas in childhood: prognostic factors and treatment.

The prognostic factors and survival data were analyzed for 35 children (aged under 16 years at diagnosis) with childhood infatentorial ependymomas treated surgically at The Hospital for Sick Children in Toronto during the years 1970 to 1987. Tumor histology was reviewed individually and grouped into three categories (Categories I to III) for survival analysis. An overall 5-year survival rate of 44.6% was obtained after the exclusion of perioperative mortality. Factors associated with an improved 5-year survival rate were: total tumor removal, noninvasive tumors, Category I histology, age greater than 6 years, and absent physical signs of parenchymal invasion or lower cranial nerve involvement. The 5-year survival rate was lower when associated with Category III histology, brain-stem or cranial nerve signs, age less than 2 years, tumor invasion and/or cranial nerve involvement, and subtotal tumor removal. Clinical evidence of spinal metastases was found to be uncommon (3.1%). Surgical excision followed by radiation therapy was the primary mode of treatment for these tumors. Different approaches regarding the volume of radiotherapy to be delivered and the use of adjuvant chemotherapy are discussed.

Adolescent↗
PubMed1990

Organelle pathology in metabolic neuromuscular disease: an overview.

The spectrum of metabolic neuromuscular disorders is wide. Most inherited metabolic diseases are related to enzyme defects within lysosomes but recent advances emphasize abnormalities of mitochondria, peroxisomes and intermediate filaments. In this overview, organelle pathology is described in the context of both the clinical manifestations and the biochemical and/or molecular aspects of the disease. Among the many clinical presentations of mitochondrial disorders three emerge as distinctive entities: mitochondrial encephalopathy with lactic acidosis and stroke-like symptoms, mitochondrial encephalopathy with ragged-red fibers, and Kearns-Sayre syndrome. Peroxisomal disorders are associated with numerous biochemical defects, the most frequent of which are Zellweger's syndrome, neonatal adrenoleukodystrophy, and infantile Refsum's disease. Disorders of cytoskeletal proteins are associated with distinctive pathological accumulation of intermediate filaments but are without confirmed evidence of a biochemical defect. Understanding the role that organelle pathology plays in the pathogenesis of cellular disturbance or demise is essential to the elucidation of the pathogenesis of metabolic disorders.

Humans↗
PubMed1989

Primary intracranial neoplasms in the first year of life.

Forty-one infants with histologically verified primary intracranial neoplasms were studied who had been diagnosed and treated during the first year of life at the Hospital for Sick Children during the years 1975-1986. Forty-one percent of tumors were astrocytomas, 22% were primitive neuroectodermal tumors, and 20% were choroid plexus papillomas. Seventy-one percent were located in the supratentorial compartment and 29% in the infratentorial compartment. Thirty percent were in the cerebral hemisphere, 12% in the optic pathway-hypothalamic region, 5% in the thalamus, 17% in the cerebellum, 5% in the brain stem, 12% in the lateral ventricles, 12% in the III ventricle, and 7% in the IV ventricle. The most common presenting features in this series of patients were vomiting and increasing head size. The symptoms and signs before diagnosis were present for 2 months or less in 87% of cases. Forty-four percent of the tumors were totally resected while only a partial resection or biopsy was carried out in 56%. Sixty-six percent of the patients required a CSF diversionary shunt. Twenty-nine percent of patients received radiotherapy. Slightly more than half of these received radiotherapy immediately after surgery, whereas delayed radiation therapy was performed in the remainder. The surgical mortality was 7.3%. Of the entire group, 39% have died, with most dying within 6 months of surgery. Treatment, survival relative to histologic type, psychomotor development, and neurologic function of the survivors are discussed.

Age Factors↗
PubMed1989

Dendrites, dementia and the Down syndrome.

Findings from a Golgi study of the visual cortex in patients with the Down syndrome were compared with those from neurologically normal, age-matched control subjects. The dendritic atrophy seen in childhood continued into adulthood, with a marked decrease in dendritic branching, dendritic length, and spine frequency in elderly adults with the Down syndrome. Subject more than 30 years old occasionally had degenerating pyramidal neurons in the cerebral cortex and degenerated pyramidal neurons and aspiny stellate cells, particularly in the temporal cortex. These dendritic abnormalities may be related to mental retardation in children and early dementia in older adults who have the Down syndrome. The genetic and extrinsic factors may be important determinants of Alzheimer type dementia in the Down syndrome.

Adult↗
PubMed1989

Dendritic pathology: an overview of Golgi studies in man.

Study of dendritic morphology through Golgi impregnation techniques has significantly furthered our understanding of neuronal development, maturation, and senescence. It has also provided insight into the pathogenesis of a wide spectrum of disease processes ranging from brain malformations to degenerative disorders. Golgi impregnation remains virtually the only method for demonstrating dendritic morphology. It delineates the profile of the individual neuron and its dendritic ramifications with unsurpassed clarity. Although it has been widely applied to experimental neuroscience involving animal tissue, its application to human material has been limited. This review summarizes the information on dendritic development and pathology in the human brain revealed by the use of the Golgi method.

Brain Diseases↗
PubMed1989

T2 values in the human brain: comparison with quantitative assays of iron and ferritin.

Magnetic resonance (MR) imaging with a whole-body imager was performed in 10 fresh, unfixed whole human brains selected randomly from cadavers. All subjects were neurologically intact before death. T2 time constants were measured within the caudate nucleus, putamen, globus pallidus, cortical gray matter, subcortical white matter, and optic radiation. These regions were then excised, and T2 values were measured again with a 1.5-T MR spectrometer. Quantitative assays of iron, ferritin, and protein from these areas were then performed. Iron concentration varied significantly among brain regions, whereas ferritin and protein concentrations were constant among brain regions and among individuals. Neither iron nor ferritin concentration showed any consistent correlation with T2 values. Histologic examination of brain micro-sections with iron- and ferritin-specific stains of demonstrated poor correlation with biochemical assays of ferritin and iron concentrations. Results indicate that T2 values correlate poorly with iron and ferritin concentrations found in neurologically intact brains.

Adolescent↗
PubMed1988

Ependymal and choroid plexus tumors. Cytokeratin and GFAP expression.

Twenty-six ependymal and 15 choroid plexus tumors were examined with monoclonal antibody against cytokeratin using the avidin-biotin-peroxidase complex (ABC) technique. Serial sections were examined with antisera to glial fibrillary acidic protein (GFAP). In five ependymal tumors (one ependymoma, two papillary ependymomas, and two primitive neuroectodermal tumors [PNET] with ependymal cells), a variable number of cytokeratin-positive cells were present. Most tumor cells (except two PNET) were positive with GFAP antisera. Many cytokeratin-positive cells were present in all choroid plexus tumors. GFAP-positive cells were present focally in six of 11 papillomas and in one of four carcinomas. Although their staining patterns and distribution were clearly different, focal coexistence of cytokeratin and GFAP was observed in six papillomas and two ependymal tumors. Thus, some ependymal tumors (especially papillary ependymomas and occasional PNET) and many choroid plexus tumors have demonstrable positivity with antibody to cytokeratin, suggesting a transitional cell type with features of both ependyma and choroid plexus.

Carcinoma↗
PubMed1988

The association of infantile osteopetrosis and neuronal storage disease in two brothers.

Neurological manifestations in infantile osteopetrosis are common and varied, and not always attributable to the skeletal pathology. An unusual association of osteopetrosis with neuronal storage of ceroid lipofuscin is reported in two infant brothers born of nonconsanguinous parents. The first child became symptomatic at age 5 days with weight loss and vomiting. He had poor head control, hypertonia, and persistent fisting, and died at age 2 months. In the second infant, the diagnosis of osteopetrosis was confirmed at age 2 days. His neurological symptoms included blindness, deafness, and recurrent seizures. The infant died at 7 months of age. In both cases, autopsy confirmed the diffuse bony sclerosis with hepatosplenomegaly and extramedullary hematopoiesis. Neuropathological examination revealed cerebral atrophy with ventricular dilation, neuronal loss, and astrogliosis. The most striking finding was widespread accumulation of neuronal ceroid lipofuscin associated with formation of axonal spheroids. The optic nerves were compressed at the optic foramina and showed loss of myelinated axons and gliosis. Rapid Golgi impregnations of neurons from the calcarine cortex in the second infant were analyzed quantitatively, showing a reduction in the total dendritic length and number of branches. The primary defect in osteopetrosis is thought to be a lysosomal dysfunction involving the monocyte cell line from which osteoclasts are derived. Thus, the association in two brothers of osteopetrosis with accumulation of neuronal ceroid lipofuscin may not be fortuitous. The neuronal storage disorder in this instance probably reflects lysosomal dysfunction.

Brain↗
PubMed1988

Recognition memory of item, associative and serial-order information after temporal lobectomy for seizure disorder.

Children, adolescents, and young adults with temporal lobectomy judged the context of their encounters with a word (by deciding about its prior occurrence or familiarity) and also identified word attributes involving associative content and serial order (by indicating word meanings and reconstructing word sequences). Laterality of temporal lobectomy was important for identifying familiarity: individuals with right-sided temporal lobectomies made better judgements than those with left resections about the prior occurrence of target words, with the more successful performance depending on enhanced sensitivity to the familiarity or non-familiarity of what was heard. Identifying the attributes of an item, as contrasted with its prior occurrence, depended on aspects of temporal lobe disorder in conjunction with laterality: deficits of brain structure involving histopathology and significant tissue loss disrupted content memory; compromised brain function resulting from certain post-infantile seizures impaired memory for serial order. In the young brain after temporal lobectomy, there exists a functional dissociation between judging the familiarity of an event and identifying its attributes, a dissociation that depends, not only on laterality of surgery, but also on the structural and functional intactness of the residual brain.

Adolescent↗
PubMed1988

The histopathology of the hemolytic uremic syndrome associated with verocytotoxin-producing Escherichia coli infections.

Verocytotoxin-producing Escherichia coli (VTEC) infection was present in three cases of hemolytic uremic syndrome (HUS), two fatal and one non-fatal, in which detailed histopathologic investigations were conducted. Two patients had a prodrome of bloody diarrhea, one of whom required a hemicolectomy for severe bleeding. The renal histopathology was characterized primarily by glomerular thrombotic microangiopathy (TMA) with greater than 95% of glomeruli showing changes of capillary wall thickening, endothelial cell swelling, and narrowing or thrombosis of the capillary lumen. Preglomerular arterioles were frequently thrombosed, and abnormalities of the medium-sized vessels, including endothelial cell damage and thrombosis, were also commonly observed. Gastrointestinal involvement was prominent in all three cases. The colon was most severely involved, with marked mucosal and submucosal edema and hemorrhage, in the absence of significant inflammation or widespread ulceration. Microvascular angiopathy was present in all cases, with changes ranging from endothelial cell damage to overt thrombosis. Similar pathology was seen throughout the small bowel, including the presence of TMA. In one patient, typical morphologic changes of pseudomembranous enterocolitis were found in the absence of infection with Clostridium difficile. The nature of vascular involvement in the kidneys and intestinal tract supports the hypothesis that HUS is mediated by systemic toxemia, and that endothelial cells are the primary target cells for the action of verocytotoxin.

Bacterial Toxins↗