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L Adelman

Publications and source records attributed to L Adelman.

At least 19 recordsLinked to original sources
PubMed2000

Limitations of the World Health Organization classification of childhood supratentorial astrocytic tumors. Children Brain Tumor Consortium.

BACKGROUND: In the context of many implied but not rigorously stated histologic feature combinations, the World Health Organization (WHO) classification of astrocytic tumors specifies only the presence or absence of endothelial proliferation, necrosis, and mitosis to distinguish astrocytoma, anaplastic astrocytoma, and glioblastoma multiforme. METHODS: The authors examined the effects of these and other reliably recognized histologic features on survival in the Childhood Brain Tumor Consortium (CBTC) sample of 340 children with supratentorial astrocytic tumors. RESULTS: Overall, the WHO criteria distinguished only two prognostically distinct classes of astrocytomas. When the specific combinations of the three features were unambiguously designated, three diagnostic categories resulted. These revised diagnostic categories are consistent with WHO guidelines and have significantly different survival distributions. However, neither the original WHO diagnoses nor the revised categories adequately separated these tumors prognostically, because histologic features other than those specified by WHO were significantly associated with improved or worsened survival. CONCLUSIONS: Classifications based on small numbers of specified histologic features may not be feasible because they inadequately separate childhood astrocytic tumors into prognostically homogeneous groups. Preferable classification techniques are those that simultaneously account for all reliably recognized histologic features.

Adolescent↗
PubMed2000

A case of Balamuthia mandrillaris meningoencephalitis.

Balamuthia mandrillaris is a newly described pathogen that causes granulomatous amebic encephalitis, an extremely rare clinical entity that usually occurs in immunosuppressed individuals. We report a case of pathologically proven Balamuthia encephalitis with unusual laboratory and radiologic findings. A 52-year-old woman with idiopathic seizures and a 2-year history of chronic neutropenia of unknown cause had a subacute illness with progressive lethargy, headaches, and coma and died 3 months after the onset of symptoms. Cerebrospinal fluid (CSF) glucose concentrations were extremely low or unmeasurable, a feature not previously described (to our knowledge). Cranial magnetic resonance imaging scans showed a single large temporal lobe nodule, followed 6 weeks later by the appearance of 18 ring-enhancing lesions in the cerebral hemispheres that disappeared after treatment with antibiotics and high-dose corticosteroids. The initial brain biopsy specimen and analysis of CSF samples did not demonstate amebae, but a second biopsy specimen and the postmortem pathologic examination showed Balamuthia trophozoites surrounded by widespread granulomatous inflammation and vasculitis. The patient's neutropenia and antibiotic use may have caused susceptibility to this organism. Amebic meningoencephalitis should be considered in cases of subacute meningoencephalitis with greatly depressed CSF glucose concentrations and multiple nodular lesions on cerebral imaging. Arch Neurol. 2000;57:1210-1212

Amebiasis↗
PubMed1998

Prognostic limitations of the Daumas-Duport grading scheme in childhood supratentorial astroglial tumors.

The Daumas-Duport grading scheme (DDGS) is a commonly used method for determining the grade of a tumor. It scores 4 histologic features and is used as a prognostic tool in adult astroglial tumors. This system of assigning children to prognostically homogeneous groups has not been evaluated. The Childhood Brain Tumor Consortium (CBTC) database includes 327 children with a CBTC assigned World Health Organization (WHO) diagnosis of supratentorial astroglial tumor and histologic features necessary for Daumas-Duport grading. We compared survival estimates for tumors within and between DDGS grades using a slightly broadened definition of endothelial prominence. The DDGS yielded only 3 histologic groups in children and only 2 prognostically differing groups. Subgroups within DDGS grades had significantly different survival distributions. The summing of 4 disparate histologic features in the DDGS is inadequate for the assessment of childhood supratentorial astroglial tumors. A classification system more fully summarizing the complete histologic content of tumors is most likely to provide diagnoses useful for clinical purposes.

Adolescent↗
PubMed1997

New structure, the "olfactory pit," in human olfactory mucosa.

A whole-mount immunocytochemical method was devised to study the olfactory receptor neurons on the surface of the human olfactory mucosal sheet. Antibodies to neuron-specific tubulin and/or microtubule-associated protein 5 and phosphorylated neurofilament protein were used. Specimens taken at autopsy from 56 patients ranging in age from 2 days to 92 years revealed a structure not previously described, an olfactory pit. Round or oval openings with a diameter of 50 to 500 microns were observed on the surface of the olfactory epithelium in the whole-mount specimen. The morphology, number, and distribution of these openings varied among the different individuals. A detailed analysis of these structures was carried out by rehydrating and sectioning the whole-mount specimens. The olfactory pit (OP) is a blind pouch lined with olfactory epithelium (OE), which appears as an invagination of OE into the connective tissue, with a depth varying between 150 and 200 microns. In some sections through an OP, a thick axon bundle emerging from the bottom of the pouch was visible. The extension and termination of this axon bundle in the central nervous system has not been explored. We have found OPs in monkey olfactory mucosa, but none in rodents. The function of the pit specialization is unclear, but it appears to be a feature of normal, young epithelium. The configuration of the blind pouch may prolong odorant association with the olfactory receptor neurons, or the OP may contain specialized neurons that have not yet been recognized by morphological, biochemical, or functional techniques.

Adult↗
PubMed1994

First febrile seizures. Characteristics of the child, the seizure, and the illness.

Through interviews with parents, data were gathered about 910 first febrile seizures in children aged 8 to 34 months. A male preponderance of 57% was found (P < .001). In 29% of cases, there was a family history of febrile seizures. Eighteen percent of seizures were focal, and 7% lasted 15 minutes or more. Focal seizures were much more likely to be of long duration (P < .001). Otitis media was diagnosed in 32% of cases, and tonsillitis or upper respiratory infection in 12%. When compared to febrile seizures after the first birthday, febrile seizures in children aged 8 to 11 months were more than twice as likely to be longer than 15 minutes (P = .015). They were also much more likely to be followed by further seizures in the same illness (P < .001). Thus, febrile seizures in children younger than 1 year are more likely to have the characteristics known to increase the risk of later nonfebrile seizures.

Age Factors↗
PubMed1993

CT-guided stereotactic biopsy of nonenhancing brain lesions.

The majority of computer tomography stereotactic biopsy lesions enhance after administration of intravenous contrast, whereas patients with nonenhancing lesions are often followed conservatively or undergo craniotomies. There are few studies showing the effectiveness of stereotactic biopsies of nonenhancing cerebral lesions. Stereotactic biopsies were performed on 19 patients with lesions that did not enhance on CT after intravenous contrast. Pathological diagnoses were made in 90% (17/19) of patients. Four HIV-positive patients had progressive multifocal leukoencephalopathy, 11 patients had gliomas (4 astrocytomas, 6 anaplastic astrocytomas, and 1 ganglioma), 1 had multiple sclerosis, and 1 had herpes encephalitis. In 2 patients multiple biopsies revealed only gliosis. There was no morbidity or mortality. Stereotactic biopsies for nonenhancing brain lesions have a high diagnostic yield and can favorably alter the treatment course.

AIDS Dementia Complex↗
PubMed1993

Real-time expert systems interfaces, cognitive processes, and task performance: an empirical assessment.

In this experiment we investigated the effect of different real-time expert system interfaces on operators' cognitive processes and performance. The results supported the principle that a real-time expert system's interface should focus operators' attention on where it is required most. However following this principle resulted in unanticipated consequences. In particular, it led to inferior performance for less critical, yet important cases requiring operators' attention. For such cases operators performed better with an interface that let them select where they wanted to focus their attention. Having a rule generation capability improved performance with all interfaces but did so less than hypothesized. In all cases performance with different interfaces and a rule generation capability was explained by the effect of the interfaces on cognitive process measures.

Aircraft↗
PubMed1992

Early Guillain-Barré syndrome without inflammation.

A patient with typical acute Guillain-Barré syndrome died 72 hours after his first symptoms occurred, and an autopsy was performed 8 hours after his death. Extensive sampling of cranial and peripheral nerves, sensory ganglia, and autonomic nerves showed only minimal inflammatory lymphocytic and macrophage infiltrates. This case, one of the earliest studied extensively, represents an extreme example of a noninflammatory mechanism that has been proposed in some cases of Gullain-Barré syndrome.

Cranial Nerve Diseases↗
PubMed1992

Temporal trends among childhood brain tumor biopsies. The Childhood Brain Tumor Consortium.

We sought temporal trends in the demographic, clinical, histologic feature, diagnostic class, and quality of life data over the interval 1930-1979 in the Childhood Brain Tumor Consortium database. The proportion of children younger than eight years old declined from 72% to 55% and the proportion of those older than ten more than doubled from 12% to 27%. The relative frequency of tumors in the supratentorial compartment increased significantly, while infratentorial tumors decreased. We found significant declines in supratentorial ependymomas and pilocytic astrocytomas. Similarly, some infratentorial tumors, especially ependymomas, decreased and brain stem tumors increased. Infratentorial medulloblastoma (primitive neuroectodermal tumor) increased significantly. Some individual histologic features which are markers of anaplasia increased in frequency in both supratentorial and infratentorial tumors. There was a significant increase in biopsies that contained nonneoplastic neural tissue in addition to tumor for both compartments and among supratentorial tumors there was a marked increase in the proportion of cases containing an indistinct neural tissue boundary. The probability of postoperative death declined, but the probability of survival five or ten years after surgery did not improve significantly for children who had tumors in either compartment. Among children who survived five years after the initial craniotomy, the proportion who had significant long term deficits increased. Most of this increase occurred in the last decade (1970-79). In this decade, the proportion of children for whom no deficits were reported five years following operation was 4% if they had a supratentorial tumor and 27% if they had an infratentorial tumor. The proportions of children alive five years following first surgery who had arachnoidal metastases increased significantly for infratentorial tumors.

Adolescent↗
PubMed1991

Pathologic changes in olfactory neurons in Alzheimer's disease.

Olfactory deficits and degenerative changes in central olfactory pathways are prominent in patients with Alzheimer's disease (AD). We hypothesized that peripheral olfactory neurons that reside in the nasal epithelium would show degenerative changes similar to the characteristic pathologic features of AD brain. Immunohistochemical studies of nasal tissue taken at autopsy reveal extensive degeneration in the sensory epithelium as well as abnormal neurites that share immunoreactive epitopes with dystrophic neurites and neurofibrillary tangles of the AD brain. The neuritic masses are stained with well-characterized monoclonal antibodies that do not normally stain olfactory neurons but which are very reactive with dystrophic neuritic structures and neurofibrillary tangles in AD brain. These include antibodies to phosphorylated and nonphosphorylated neurofilament subunits, tau, and also ALZ50, which is characteristically reactive with AD but not with normal brains. Such changes are present in 81% of AD patients. Similar accumulations of ectopic neurites are found in the olfactory epithelium of about 22% of non-demented patients. Preliminary statistical analysis fails to reveal any age-linked association. It has been proposed that the aged monkey is a good model for AD inasmuch as amyloid accumulations similar to those of humans are found in monkey brain. We examined a series of 13 rhesus monkeys, including aged animals with behavioral deficits. Although the olfactory epithelium was very similar to that of humans, no abnormal olfactory structures were observed. Aged rhesus monkeys do not appear to be a good model for the neuritic abnormalities of AD.

Alzheimer Disease↗
PubMed1989

Pathological changes in olfactory neurons in patients with Alzheimer's disease.

Alzheimer's disease is a central nervous system disorder characterized by the presence of neurofibrillary tangles, neuritic plaques and dystrophic neurites in susceptible areas of the brain. Investigation of the mechanism and development of the disease has been hampered by the lack of an animal model and the inaccessibility of neural tissue during the illness. Deficits in odour detection and discrimination are among the signs of Alzheimer's and previous anatomical studies suggest that olfactory pathways may be involved early in the illness. Neurons in the olfactory epithelium, which are of central origin, are relatively accessible for biopsy and could be used as a source of living nerve cells for the study of Alzheimer's disease if they can be shown to have characteristics of this disease. As these neurons have the unusual property of arising from stem cells throughout the life of the organism, they are good candidates for the development of cell cultures or cell lines which may express the disorder from living patients. We report here that nasal epithelium tissue taken at autopsy shows unique pathological changes in morphology, distribution and immunoreactivity of neuronal structures in patients with Alzheimer's disease.

Adult↗
PubMed1987

Effect of spinal cord TRH deficiency on lower motorneuron function in the rat.

Thyrotropin-releasing hormone (TRH), present in high concentrations in the mammalian spinal cord, exerts excitatory effects on the alpha-motorneuron (AMN) via axodendritic contacts. We used the neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) to deplete TRH from the ventral horn of the spinal cord of adult rats to determine whether the tripeptide may be trophic to the AMN. The rats were studied blindly and sequentially for 11 weeks. Motor performance remained normal by clinical and electrophysiologic assessments. AMN counts were not reduced in the lumbar cord, and gastrocnemius muscle showed no evidence of denervation in treated rats. We conclude that in the adult rat chronic ventral horn TRH deficiency does not lead to AMN degeneration and is not associated with a significant alteration of AMN function.

5,7-Dihydroxytryptamine↗
PubMed1987

Dental chair intracerebral hemorrhage.

A 52-year-old woman had a fatal intracerebral hemorrhage after dental manipulation. Normotensive in the past, the initial blood pressure was high but rapidly returned to normal. Necropsy showed no vascular malformation or evidence of hypertensive vascular disease. Clinical and experimental data show that stimulation of trigeminal fibers can cause important changes in blood pressure and pulse.

Cerebral Hemorrhage↗
PubMed1986

Anti-lymphocyte antibody Leu-7 (HNK-1) recognizes a constituent of neuroendocrine granule matrix.

Anti-lymphocyte monoclonal antibody HNK-1 (Leu-7) reacts with the cell surfaces of natural killer (NK) lymphocytes and with myelin-associated glycoprotein (MAG). This antibody reacts intensely with normal and neoplastic adrenal medullary cells. A small proportion of normal pancreatic islet cells, anterior pituitary, and gastroenteropancreatic endocrine cells also show Leu-7 immunoreactivity. In adrenal medulla, ultrastructural immunocytochemical studies and immunoblot analyses reveal that Leu-7 reacts with an intracellular protein of MW 75 KD which is localized within the matrices of the chromaffin granules. The MW of this protein differs from those of MAG and chromogranin A. The findings suggest that Leu-7 immunoreactivity might be a new marker for specific subsets of secretory granules.

Adrenal Gland Neoplasms↗
PubMed1982

Familial granulovacuolar lobular myopathy with electrical myotonia.

We report 3 patients with a myopathy characterized by profound selective muscle wasting and weakness, electrical myotonia without clinical myotonia and an unusual muscle biopsy. Cryostat sections showed muscle fibers with vacuoles containing hematoxylinophilic granules, and 30% of type I fibers showed demarcation of their sarcoplasm into "lobules" due apparently to reorganization of myofibrillar elements. The electrical myotonia suggests an underlying muscle membrane defect. Two of the patients are siblings suggesting that the disorder may be inherited.

Adult↗