PubMed Health⌕ Search

Biomedical subjects

J T Hughes

Publications and source records attributed to J T Hughes.

At least 19 recordsLinked to original sources
PubMed2002

George Scharpe, c.1581-1637. A Scots doctor at Montpellier.

Before the eighteenth century many Scots studied medicine at the medical schools of Europe, of which Montpellier was frequently the choice. George Scharpe, an early student of the University of Edinburgh, graduated in medicine at Montpellier and joined the medical faculty, where his long career can be traced from contemporary records. The practice of Scots studying abroad is described, as is Languedoc in the early seventeenth century a region and period devastated by the religious wars of France.

France↗
PubMed1994

Electromagnetic fields and brain tumours: a commentary.

Brain tumours are of different cell types, the commonest being tumours of glia called gliomas. Many etiological factors of gliomas have been suggested and certain industries have been implicated. Several epidemiological studies have linked electromagnetic fields (EMFs) to gliomas. Health effects of EMFs have been studied, both in humans and in experimental animals, mainly with negative findings. Positive experimental evidence linking EMFs to tumours is the effect of EMFs on melatonin production by the pineal gland. Removal of the pineal gland in rats increases the incidence of tumours. Further epidemiological and experimental evidence is required to elucidate this possible link between EMFs and brain tumours.

Brain Neoplasms↗
PubMed1994

Use of a calcium channel blocker (nicardipine HCl) in the treatment of childhood moyamoya disease.

Moyamoya disease is a cerebrovascular disease characterized radiologically by progressive narrowing and occlusion of the arteries contributing to the circle of Willis and its branches. There is formation of an exuberant collateral network of blood vessels at the base of the brain, which is thought to arise in response to chronic ischemia. Clinically, the course is variable, with patients having repeated transient ischemic attacks, strokes, migraine, and seizures. Effective treatment is not available. The etiology and pathophysiology of moyamoya disease are largely unknown. Two patients with arteriographically proven moyamoya disease were identified. Both patients were symptomatic before age 5 years. Despite successful encephaloduroarteriosynangiosis revascularization procedures, they continued to experience an inexorable downhill course. A calcium channel blocker (nicardipine HCl) was introduced in order to prevent further symptoms. After the introduction of nicardipine, no further strokes occurred in either patient. There were no further episodes of transient ischemic attacks, seizures, or headache in one patient and decreased frequency in the other. In patients with moyamoya disease, nicardipine may have a beneficial effect on cerebral hemodynamics and may prevent ischemic sequelae by optimizing existing collateral circulation.

Carotid Stenosis↗
PubMed1994

Legal aspects of epilepsy.

Legal issues must be considered in caring for patients with epilepsy. Doctors caring for people with epilepsy may be legally involved in three primary ways: as the agent of social control, as patient advocate, and as the target of liability or malpractice suits. This article examines these factors and the implications for patients and their caregivers.

Accidents, Traffic↗
PubMed1993

Prion diseases.

Explore the source record for details and available documents.

Animals↗
PubMed1991

Homozygous prion protein genotype predisposes to sporadic Creutzfeldt-Jakob disease.

The human prion diseases, Creutzfeldt-Jakob disease (CJD) and Gerstmann-Sträussler syndrome (GSS), are neurodegenerative diseases that are unique in being both infectious and genetic. Transmission of both diseases and the animal spongiform encephalopathies (for example, scrapie and bovine spongiform encephalopathy) to experimental animals by intracerebral inoculation with brain homogenates is well documented. Despite their experimental transmissibility, missense and insertional mutations in the prion protein gene are associated with both GSS and familial CJD, demonstrating that the human familial cases are autosomal dominant diseases. More than 80% of CJD cases occur sporadically, however, and are not known to be associated with mutations. Here we report that 21 of 22 sporadic CJD cases and a further 19 of 23 suspected sporadic CJD cases are homozygous at the polymorphic amino-acid residue 129; 51% of the normal population are heterozygous at this site. We argue that homozygosity predisposes towards sporadic CJD and that this directly supports the hypothesis that interaction between prion protein molecules underlies the disease process.

Amino Acid Sequence↗
PubMed1991

Differentiation in embryonal neuroepithelial tumors of the central nervous system.

Ninety-six embryonal neuroectodermal tumors were studied histologically and immunohistologically with a panel of antibodies including glial, neuronal, epithelial, mesodermal, and myelin markers. In 71 tumors there was glial and neuronal differentiation and expression both of an S (photoreceptor) antigen and vimentin. In five tumors there was only glial differentiation and in 20 tumors only neuronal differentiation. No reactivity for myelin and epithelial markers was found. Histologic and immunohistologic findings identified various degrees of differentiation in different tumors, which was bipolar (glial and neuronal) in most tumors and unipolar in the remainder. The authors suggest that their findings may be the result of normal or aberrant oncogenic differentiation, agreeing with the nomenclature of the World Health Organization classification for these tumors with and the inclusion of a category for ependymoblastoma.

Adolescent↗
PubMed1991

Neuropathology of the spinal cord.

The neuropathology of the spinal cord is described and illustrated from the viewpoint of a neuropathologist observing at necropsy the many traumas and pathologic diseases affecting the spinal cord. The article provides the clinician with an insight into the disease processes and anatomic derangements underlying the neurologic deficits in paraplegia and quadriplegia. Today, the clinical examination of patients with spinal cord trauma or spinal cord disease is greatly assisted by many anciliary investigations, notably, radiology and the newer imaging techniques now applied to successfully to the spinal cord. Comparison of the patient's neuropathology with the classical neurophathology of the spinal cord, provided in this article, remains important for the clinician.

Humans↗
PubMed1990

Epidermal growth factor receptor expression in 72 meningiomas.

The expression of epidermal growth factor receptor (EGF-R) was studied immunohistochemically in 72 meningiomas using two monoclonal antibodies with specificities to protein and carbohydrate components, respectively, of the external domain of the EGF-R. One third of the tumors had cytoplasmic and membrane positivity with the protein-specific antibody but in none were there positive tumor cells with the carbohydrate-specific antibody which recognizes the blood group A antigen. There was no difference in EGF-R expression between typical and aggressive meningiomas. No evidence was found to support previous reports of specific EGF-R immunoreactivity in the vascular endothelial cells of meningiomas. The authors believe this discrepancy to be due to detection of normal blood group A antigen attached to endothelial cells in patients of blood group A or AB. This occurs because many monoclonal anti-EGF-R antibodies are specific for A antigen which is found on the EGF-R of A431 cells but has not been reported on EGF-R elsewhere.

Animals↗
PubMed1990

Investigation of the expression of epidermal growth factor receptor and blood group A antigen in 110 human gliomas.

The presence of epidermal growth factor receptor (EGF-R) and blood group A antigen was studied immunohistochemically in a series of 110 malignant gliomas using monoclonal antibodies. Fifty-seven percent of the tumours strongly expressed EGF-R on the malignant cells. Although blood group A antigen is present on EGF-R of A431 cells (a cell line derived from a human epidermoid carcinoma), in gliomas it was found only on vascular endothelial cells of tumours from blood group A patients. The results suggest that the EGF-R present in gliomas differs from that in A431 cells in the type or amount of the carbohydrate chains. This is in contrast to previous reports which have suggested that A antigen is present on EGF-R in gliomas. This has relevance in the choice of monoclonal antibodies used to study the EGF-R, as those directed against the A antigen component of the A431 cell EGF-R will not recognize EGF-R elsewhere and may cause normal blood group A antigen to be mistaken for EGF-R.

ABO Blood-Group System↗
PubMed1990

Haemangioblastoma: histological and immunohistological study of an enigmatic cerebellar tumour.

Paraffin-embedded blocks of 36 cerebellar haemangioblastomas were reacted with a panel of antibodies including glial fibrillary acidic protein, vimentin, epithelial membrane antigen, cytokeratin, Factor VIII, a neuroendocrine marker and with Ulex europaeus. agglutinin The main histological features, apart from the characteristic large abnormal vessels, were a prominent reticulin network, a cystic architecture and cellular and nuclear polymorphism. Two cell types were identified: endothelial and stromal. Twenty tumours were positive for glial fibrillary acidic protein because of included or reactive astrocytes as well as positive stromal cells. Vimentin was positive in all tumours with a diffuse distribution and a somatic pattern; blood vessels, stromal cells and reactive astrocytes were strongly positive. Factor VIII and Ulex europaeus agglutinin reactivity were present in a similar pattern of staining in endothelium and in five cases there were stromal cells that were positive with the latter. We were not able to ascertain the histogenesis of the stromal cell, which remains enigmatic.

Adolescent↗