Biomedical subjects

T J Cummings

Publications and source records attributed to T J Cummings.

29 records · Page 2Linked to original sources

PubMed1996

Serotonin depletion exacerbates changes in striatal gene expression following quinolinic acid injection.

Controversy exists as to whether serotonin (5-HT) plays a neuroprotective role during brain injury. We sought to determine if prior 5-HT depletion alters gene expression patterns normally associated with NMDA receptor-mediated excitotoxicity of the rodent striatum. Adult male Sprague-Dawley rats were treated systemically with saline or p-chlorophenylalanine (pCPA, 350 mg/kg) to block 5-HT synthesis. After 3 days, these rats received unilateral injection (1 microliter) of quinolinic acid (QA, 40 micrograms in 0.1 M phosphate buffered saline, pH 7.4) or saline vehicle directly into the anterior striatum. All rats were sacrificed 6 or 48 h later. Striatal tissues containing the saline or QA injection site were subjected to Northern analysis of preprotachykinin (PPT), preproenkephalin (PPE), and zif/268 mRNAs, as well as HPLC-EC detection of monoamines. At the time of the intrastriatal injection, 5-HT levels were depleted greater than 95% by pCPA as compared to saline controls. At 48 h post-QA injection, PPT and PPE mRNAs were markedly reduced within the striatal lesion site of saline/QA and pCPA/QA groups with respect to their contralateral uninjected control sides. In the pCPA/QA group, striatal PPE and PPT mRNA levels were further reduced as compared to the saline/QA group with PPE mRNA reductions reaching statistical significance at 95% (ANOVA with Scheffe F-test). Exacerbation of the excitotoxic lesion in the 5-HT depleted rat was further exemplified by a larger increase in zif/268 mRNA measured at 6 h post-intrastriatal injection in the pCPA/QA group as compared to saline/QA animals (P < 0.05 by ANOVA with Scheffe F-test). These results suggest that 5-HT depletion may adversely affect neuronal survival following intrastriatal QA exposure and lend support to the hypothesis that increasing 5-HT levels during NMDA receptor-mediated excitotoxicity may spare neurons destined to degenerate.

Animals↗

PubMed1995

Positron emission tomography in pediatric epilepsy.

PET is an additional tool in the armamentarium to provide improved care to children and infants with epilepsy. It provides important lateralizing information noninvasively, thus avoiding the need for depth or subdural electrodes in most instances. It can be invaluable when CT and MR imaging do not show a structural lesion. When it corresponds to an EEG focus of epileptogenicity, intraoperative electrocorticography may be used to delineate further the extent of surgical resection, often with impressive reduction in the seizure frequency postoperatively. As PET technology continues to improve, the clinical role of PET in the future will undoubtedly continue to grow.

Adolescent↗

PubMed1992

[Include teaching of health economics in the medical curriculum--a way of containing cost increases?].

The amount of money spent on health care and related services is expanding exponentially, and today's health bill represents an increasing share of gross national product. An understanding of economic and technical dynamics, and their impact on the health care decisions of physicians and consequently their institutions, are part of a knowledge base that may be of interest to the present and future health care community. The authors outline the present situation and suggest that a course on the economics of health care systems designed for physicians may be a way of contending with increasing health costs.

Cost Control↗

PubMedDate not supplied

Gliomatosis cerebri: cytologic and autopsy findings in a case involving the entire neuraxis.

We describe the case of a 7-year-old girl who was clinically diagnosed as having a pontine glioma based on magnetic resonance imaging studies. Neoplastic cells were identified upon cytologic examination of cerebrospinal fluid. Autopsy studies revealed an anaplastic astrocytoma (WHO grade III) diffusely infiltrating the cerebral hemispheres, brain stem, cerebellum, leptomeninges, and spinal cord to the level of the conus medullaris. The Ki-67 labeling index focally approached 30%. Although many of the neoplastic cells displayed elongated twisted nuclei reminiscent of microglia, these cells stained intensely for glial fibrillary acidic protein, supporting an astrocytic origin. Unusual features of this case of gliomatosis cerebri include involvement of the entire central neuraxis, correlation with pre-mortem lumbar puncture cytology, and a markedly elevated Ki-67 labeling index.

Astrocytoma↗

PubMedDate not supplied

Meningioma of the fourth ventricle.

Meningiomas are primary meningeal based tumors of the central nervous system that rarely are located strictly within the fourth ventricle. We report a 72-year-old man operated upon for such a tumor. The pre-operative magnetic resonance images revealed a well circumscribed mass in the fourth ventricle that exhibited a low signal on T1-weighted magnetic resonance images and homogenously enhanced with gadolinium. By light microscopy the tumor was composed of tightly packed spindle cells separated by collagen. Immunohistochemistry showed the tumor cells to be positive for vimentin and epithelial membrane antigen, and negative for glial fibrillary acidic protein. Electron microscopy revealed typical findings of meningioma, including interdigitating cell processes, desmosomes, and intermediate filaments. Although rare, fibroblastic meningioma must be included in the differential diagnosis of a fourth ventricular spindle cell tumor in elderly patients.

Aged↗

PubMedDate not supplied

Biphasic malignant meningioma: a comparative genomic hybridization study.

To ascertain if a carcinoma-like component within a fibroblastic meningioma represented a metastatic carcinoma to a meningioma or malignant progression, we employed traditional immunohistochemical methods as well as comparative genomic hybridization (CGH) which compares chromosomal alterations. Vimentin and epithelial membrane antigen were strongly immunoreactive in both the fibroblastic and carcinoma-like components. The CGH profile in both components had similar chromosomal alterations, including losses of 1p, 14, 16p13-->p10 and 22. However, the CGH profiles from the fibroblastic component showed losses of 4p, 10q23-->q24 and 18, along with gains of 1q, 6q25-->qter and 13q32-->qter. The profile of the carcinoma-like component showed losses of chromosome 4, in addition to gains of 3p12-->q13.11, 5q14.3-->q23.2, 6pter-->p23, and 13q14.2-->qter. CGH analysis of a biphasic malignant meningioma confirmed that the disparate histologic components were genetically related and likely derivative from a common precursor, demonstrating genetic instability and clonal expansion. Furthermore, CGH showed that the histologically appearing low-grade fibroblastic component had not solely the characteristic alterations of a benign meningioma but had already progressed to an atypical meningioma.

Aged↗

PubMedDate not supplied

The pathology of extracranial scalp and skull masses in young children.

OBJECTIVE: Extracranial subcutaneous masses involving the scalp and/or skull in young children are uncommon lesions that get excised by the neurosurgeon. Although the most common reported lesion is the dermoid cyst, our experience suggests that the spectrum of pathology in these lesions can present diagnostic challenges to the pathologist. MATERIAL: We reviewed 30 consecutive extracranial masses from 29 patients between July 1998 and June 2003. METHOD: Hematoxylin and eosin-stained sections were reviewed in all cases, and immunohistochemistry was performed in select cases. RESULTS: Twenty-three were within the scalp, 5 involved the scalp and skull and 2 were within the limits of the inner and outer tables of the skull. There were 8 dermoid cysts, 2 epidermoid cysts, 6 post-traumatic lesions including 3 calcified cephalhematomas and 3 pseudocysts, 5 vascular lesions including 3 capillary hemangiomas, 1 venous angioma and 1 lymphangioma, 2 cases of cranial fasciitis and 1 case each of benign teratoma, deep granuloma annulare, benign fibrous histiocytoma, congenital melanocytic nevus, hamartoma with ectopic meningothelial elements, cutaneous hyalinised ectopic meningioma and a meningocele with a fibrohistiocytic reaction. No lesions have recurred or exhibited malignant features. CONCLUSIONS: Surgical pathologists and neuropathologists should be aware that the differential diagnosis of "lumps and bumps on babie's heads" is quite varied and can be histologically challenging.

Child, Preschool↗

PubMedDate not supplied

Extraskeletal myxoid chondrosarcoma of the jugular foramen.

OBJECTIVE: To report a case of an extraskeletal myxoid chondrosarcoma (EMC) arising from the jugular foramen. EMCs are tumors usually seen in the deep soft tissues of the extremities and are rarely seen within the intracranial cavity. The histological differential diagnosis includes chordoma, conventional chondrosarcoma and chordoid meningioma, among others. A distinguishing feature of EMC is their characteristic reciprocal translocation t(9;22)(q22;q12). MATERIAL: A 63-year-old man presented with progressive hearing loss and gait imbalance. Magnetic resonance imaging showed a heterogeneously enhancing 2.4 cm mass in the cerebellopontine angle. A right far lateral transcondylar skull base approach with gross total removal of the tumor was performed. Intraoperative findings showed that the mass appeared to arise from the glossopharyngeal nerve within the jugular foramen. METHOD: Histology, immunohistochemistry, and fluorescence in situ hybridization studies were performed. RESULTS: Histological and immunohistochemical studies were compatible with the diagnosis of EMC. Fluorescence in situ hybridization studies showed disruption of the EWS gene locus at 22q12 and added further support to the diagnosis. CONCLUSIONS: We report a rare case of EMC arising from the jugular foramen, and the diagnosis of EMC can be supported by confirmation of disruption of the EWS gene locus.

Brain Neoplasms↗

PubMedDate not supplied

Malignant peripheral nerve sheath tumor of the spine after radiation therapy for Hodgkin's lymphoma.

We report the development of a malignant peripheral nerve sheath tumor (MPNST) in 2 patients after irradiation for Hodgkin's lymphoma. Clinicians should be aware of this uncommon, but important fatal complication of radiation therapy. The first case is a 37-year-old man who was diagnosed with nodular sclerosing (NS) Hodgkin's lymphoma and underwent successful mantle radiation. He presented to our neurosurgery service with a left C6 radiculopathy 6 years later. The second case is a 30-year-old female diagnosed with NS Hodgkin's lymphoma. She did well with extensive radiotherapy until 5 years later when she developed severe right arm and chest pain secondary to recurrent lymphoma. After aggressive radio- and chemotherapy, she presented to the neurosurgery service with a right Horner's syndrome, right C6 radiculopathy, and weakness of her right triceps and wrist extensors. Both patients obtained magnetic resonance imaging revealing intradural extramedullary cervical nerve root associated mass lesions. Two years after radiation therapy for his Hodgkin's lymphoma, the first patient underwent a C6 laminectomy at an outside institution for resection of a benign neurofibroma. Four years later, he underwent a posterior C5-7 laminectomy with lateral mass plate fusion and partial excision of a recurrent mass diagnosed as a MPNST. The second patient underwent a C5-6 hemilaminectomy and partial resection of a tumor also pathologically consistent with MPNST. We present 2 case reports of patients who developed neurofibrosarcomatous tumors with malignant transformation after undergoing radiation therapy for Hodgkin's lymphoma. Despite prompt surgical resection, these tumors exhibited aggressive behavior. Numerous cases of soft tissue tumors have been described to arise in areas of prior radiation therapy; however, there have been rare reports of de novo MPNST after radiation therapy, especially in the setting of Hodgkin's lymphoma. Postirradiation MPNST should be considered in the differential diagnosis of a painful, enlarging mass in a previously irradiated area.

Adult↗

PubMedDate not supplied

Meningioma with eosinophilic granular inclusions.

Rare meningiomas have been described that contain eosinophilic inclusions that have a granular or granulofilamentous ultrastructure. We describe a 66-year-old woman who developed a planum sphenoidale meningioma. Histologically, the tumor was composed of meningothelial cells arranged in fascicles and whorls, typical of a well-differentiated meningioma. Many tumor cells contained round intracytoplasmic eosinophilic inclusions that were periodic acid Schiff-negative and red on Masson trichrome. The inclusions were immunopositive for vimentin, and were immunonegative for epithelial membrane antigen, smooth muscle actin, desmin and type IV collagen. Ultrastructural examination showed the inclusions were composed of round to oval, well-demarcated, non-membrane-bound, osmiophilic granular material. The inclusions within this tumor had histochemical, immunohistochemical and ultrastructural properties not described in other reported meningiomas with eosinophilic granular or granulofilamentous inclusions.

Aged↗

PubMedDate not supplied

Loss of chromosome 13 in a case of soft tissue perineurioma.

Soft tissue perineuriomas are rare mesenchymal tumors that are derived from perineurial cells of the peripheral nerve sheath. Although the histological and immunohistochemical features of soft tissue perineuriomas are well described, little is known regarding the cytogenetic abnormalities in these tumors. Herein, we describe a case of a large (12.2 cm) soft tissue perineurioma that arose in the thigh of a 26-year-old Caucasian female. Histologically, the tumor was composed of a diffuse to fascicular arrangement of spindle cells with bland, elongated nuclei with long, thin, tapering cytoplasmic processes. The immunohistochemical profile was consistent with a perineurial cell origin with expression of epithelial membrane antigen, vimentin, and collagen type IV. Cytogenetic evaluation revealed loss of chromosome 13 as the sole abnormality in the majority of examined cells. In contrast to previous reports, we were unable to demonstrate deletion or structural abnormalities of chromosome 22 by either fluorescence in situ hybridization (FISH) or metaphase cytogenetics. This is the first report of loss of chromosome 13 in soft tissue perineurioma. Although never described in this group of neoplasms, loss of chromosome 13 has been identified in a large number of other soft tissue tumors, particularly sarcomas and malignant peripheral nerve sheath tumors. Herein, we discuss this case and provide a review of the literature.

Adult↗