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P Gloor

Publications and source records attributed to P Gloor.

At least 19 recordsLinked to original sources
PubMed1999

Sebaceous carcinoma presenting as a unilateral papillary conjunctivitis.

PURPOSE: To describe a previously unreported presentation of sebaceous carcinoma, an aggressive tumor that often presents insidiously with minimal symptoms and nonspecific signs. METHODS: We report a 71-year-old man who presented with unilateral ocular irritation and ipsilateral, idiopathic, papillary changes of the superior palpebral conjunctiva. The patient underwent incisional biopsy of the palpebral conjunctiva followed by full-thickness excision of the involved eyelid. RESULT: Histopathologic examination established the diagnosis of sebaceous carcinoma. CONCLUSION: Unexplained asymmetric, papillary changes of the palpebral conjunctiva should arouse suspicion of sebaceous carcinoma.

Adenocarcinoma, Sebaceous↗
PubMed1998

Diagnosis of Fusarium keratitis in an animal model using the polymerase chain reaction.

AIMS/BACKGROUND: The purpose of this study was apply the polymerase chain reaction (PCR) to develop a sensitive, specific, and rapid test to diagnose Fusarium keratitis. Fusarium is the most common cause of fungal corneal infection in some parts of the world. It is often difficult to establish that a keratitis is due to fungal infection. METHODS: Fusarium solani keratitis was induced in three eyes of three rabbits by injection of a suspension of the fungus into the anterior corneal stroma. In one rabbit the contralateral eye served as a control. From four to 28 days after inoculation, the corneas were scraped for culture, then scraped and swabbed for PCR analysis. The PCR was performed with primers directed against a portion of the Fusarium cutinase gene, and the presence or absence of this amplified target sequence was determined by agarose gel. RESULTS: The amplified DNA sequence was detected in 25 of 28 samples from the corneas infected with Fusarium, for a sensitivity of 89%. Only three of the 14 samples from these eyes with Fusarium keratitis were positive by culture, for a sensitivity of 21%. Seven of eight control samples were negative by the PCR based test, for a specificity of 88%. CONCLUSION: This PCR based test holds promise of being an effective method of diagnosing Fusarium keratitis as well as Fusarium infections at other sites.

Animals↗
PubMed1997

Discoid lupus erythematosus presenting as asymmetric posterior blepharitis.

PURPOSE: To describe the ophthalmic findings of patients with discoid lupus erythematosus. METHOD: We describe two women who originally were thought to have asymmetric posterior blepharitis; however, the involved eyelid also had an erythematous, scaly cutaneous lesion. RESULT: In both patients, histology and immunofluorescence studies performed on cutaneous biopsy specimens established the diagnosis of discoid lupus erythematosus. CONCLUSIONS: It is important to diagnose discoid lupus of the eyelids because misdiagnosis can delay treatment and thus lead to deformities of the eyelid margin. Misdiagnosis can also lead to a complicated full-thickness eyelid biopsy and delay the diagnosis of systemic lupus erythematosus.

Adult↗
PubMed1996

Postmortem diagnosis of Fusarium panophthalmitis by the polymerase chain reaction.

PURPOSE: We undertook this study to determine if a polymerase chain reaction-based test that we developed for the filamentary fungus, Fusarium, could be used to detect the organism in postmortem ocular tissues. METHODS: We applied the polymerase chain reaction to amplify a target fragment of Fusarium DNA from formalin-fixed ocular tissues from a patient with endogenous Fusarium panophthalmitis. RESULTS: By using the polymerase chain reaction-based test, we were able to amplify the target fragment of DNA from the infected eyes, but not from uninfected control eyes. CONCLUSIONS: The technique appears to hold promise to be a sensitive, specific, and rapid method of diagnosing Fusarium infections.

Blotting, Southern↗
PubMed1996

Early history of IBRO: the birth of organized neuroscience.

To celebrate the thirtieth anniversary of the founding of the International Brain Research Organization (IBRO), a symposium was organized for the III Congress of the World Federation of Neuroscientists in Montreal to present, on 7 August 1991, the recollections of some of the early participants in IBRO's history and to place it in the context of other significant world organizations. Edited and slightly condensed transcripts of the talks together with the discussions are presented. L. Marshall reviewed the antecedent conferences that led to the Moscow Colloquium in 1958 and the subsequent formation of IBRO with UNESCO support. The ambience of that period for scientific organization on an international level was discussed by W. A. Rosenblith who emphasized how IBRO goals fitted into the rising interest in brain and behavior research. The scientific careers of six past executive secretaries were briefly reviewed by P. Gloor, with special tribute to the first, Herbert Jasper. One of IBRO's major achievements, the world survey of resources and needs in brain research, was described first-hand by G. Krauthamer. To discuss IBRO's image, C. Blakemore invoked the travails of reorganization and recovery from a period of inactivity. Finally, placing IBRO in a national and international context, S. Cozzens presented the perspective of the historian of sociology on an upbeat note.

History, 20th Century↗
PubMed1995

Intrinsic epileptogenicity of human dysplastic cortex as suggested by corticography and surgical results.

Cortical dysplastic lesions (CDyLs) are often associated with severe partial epilepsies. We describe the electrographic counterpart of this high degree of epileptogenicity, manifested by continuous or frequent rhythmic epileptogenic discharges recorded directly from CDyLs during intraoperative electrocorticography (ECoG). These ictal or continuous epileptogenic discharges (I/CEDs) assumed one of the following three patterns: (1) repetitive electrographic seizures, (2) repetitive bursting discharges, or (3) continuous or quasicontinuous rhythmic spiking. One or more of these patterns were present in 23 of 34 patients (67%) with intractable partial epilepsy associated with CDyLs, and in only 1 of 40 patients (2.5%) with intractable partial epilepsy associated with other types of structural lesions. I/CEDs were usually spatially restricted, thus contrasting with the more widespread interictal ECoG epileptic activity, and tended to colocalize with the magnetic resonance imaging-defined lesion. Completeness of excision of cortical tissue displaying I/CEDs correlated positively with surgical outcome in patients with medically intractable seizures; i.e., three-fourths of the patients in whom it was entirely excised had favorable surgical outcome; in contrast, uniformly poor outcome was observed in those patients in whom areas containing I/CEDs remained in situ. We conclude that CDyLs are highly and intrinsically epileptogenic, and that intraoperative ECoG identification of this intrinsically epileptogenic dysplastic cortical tissue is crucial to decide the extent of excision for best seizure control.

Adolescent↗
PubMed1995

Hyperpolarization of the cell membrane of mouse hepatocytes by fatty acid oxidation.

The effect of palmitate and metabolizable and nonmetabolizable monosacharides (D-glucose, D-fructose and 2-deoxy-D-glucose = 2-DG) on the membrane potential (Vm) of mouse hepatocytes was investigated employing a superfused mouse liver slice technique. Palmitate hyperpolarized the liver cell membrane in a concentration dependent manner whereas the monosaccharides tested did not. When mice were fed a fat-rich diet, the hyperpolarisation was greater in comparison to mice fed a low fat diet. The hyperpolarization was reversed by ouabain, an inhibitor of the Na+/K(+)-ATPase, by the K(+)-channel blockers tetra-ethyl-ammonium (TEA) and cetiedil and by three inhibitors of fatty acid oxidation (2-bromopalmitate, 2-bromooctanoate and 4-pentenoate). The results suggest that hyperpolarization of the liver cell membrane is due to fatty acid oxidation and that both activation of Na+/K(+)-ATPase and opening of K(+)-channels are involved. The implications of these findings with regard to control of food intake by fatty acid oxidation are discussed. The results are consistent with a role of the hepatic membrane potential in control of food intake by fatty acid oxidation.

Animals↗
PubMed1995

Clinical characterization of primary acquired melanosis.

PURPOSE: Primary acquired melanosis (PAM) is the name applied to flat, speckled, brown lesions of the conjunctival epithelium. Because there have been reports that many of these lesions progress to melanoma, biopsy of all PAM lesions, regardless of size, is recommended. This study was undertaken to determine the prevalence of PAM, provide a clinical description of the condition, and determine which factors are associated with its presence. METHODS: One hundred forty-six consecutive patients, who were outpatients at a corneal and external diseases service, who had no known non-European ancestry, and who were older than 10 years of age underwent careful slit lamp examination. RESULTS: The prevalence of PAM in the study population was 36%. Contrary to earlier reports, PAM is prevalent in young adults as well as in older patients. The presence of PAM was associated with southern European ancestry (P = 0.01), dark brown hair (P = 0.01), facial nevi (P = 0.03), pingueculae or pterygia (P = 0.01), hypertension (P = 0.02), cigarette smoking (P = 0.02), and the absence of ocular surface disease (P = 0.02). CONCLUSIONS: Because PAM is common, its transformation to conjunctival melanoma must be extremely rare, and biopsy of all PAM lesions is unwarranted. In the absence of known clinical risk factors for progression to melanoma, interim recommendations are made to perform biopsy only of those lesions that are widespread, large, thickened, dark, palpebral, unusually vascular, or progressive.

Adolescent↗
PubMed1994

Interictal discharges in the hippocampus of rats with long-term pilocarpine seizures.

Systemic administration of pilocarpine to adult rats induces an acute status epilepticus followed by spontaneous recurrent seizures after a 1-2-week silent period. We recorded field potentials in hippocampal slices obtained from rats with spontaneous recurrent seizures after pilocarpine-induced status. The frequency of the interictal discharges induced in these slices by 4-aminopyridine (4AP) was reduced and their duration was increased. Cutting the Schaffer collaterals caused interictal discharges in CA1 to disappear in normal rats and in rats 3 weeks after pilocarpine-induced status. However, 12 weeks after pilocarpine, these discharges remained in CA1 after such a cut but occurred at a lower frequency. These findings show that in rat hippocampi with a lesion similar to that of human Ammon's horn sclerosis some electrophysiological features of 4AP-induced interictal discharges are altered in comparison to those induced in normal hippocampi.

4-Aminopyridine↗
PubMed1994

Berger lecture. Is Berger's dream coming true?

In the last quarter of our century technologies have been developed that permit us to measure and localize with previously unknown precision physiological concomitants of mental activities. Human in vivo cerebral psychophysiology has come of age, decades after the discovery of EEG. In part this has come about through the development of PET and most recently dynamic MRI. However, it is hardly known today that the concepts which underlie these modern methods of studying the physiological correlates of human mental activity were the focus of Berger's early research at the onset of his scientific career at the turn of the century. Indeed at that time he attempted to study human mental function through measuring cerebral blood flow by means of plethysmography applied to patients who had pulsating skull defects. He also measured intracerebral temperature changes during neurosurgical procedures in awake, locally anesthetized, patients in a quest of identifying metabolic concomitants of mental activity. He was thus well ahead of his time, but was forced to give up these methods because they were not commensurate to the task. Only at age 50 he turned to electrophysiology and discovered the EEG. At last he was able to identify some electrophysiological facets of human psychophysiology related to attention, sleep, wakefulness and coma. This essay will illustrate some examples of PET, functional MRI, computerized EEG and cerebral electrical stimulation studies that show that Berger's conceptual approaches to human psychophysiology, even though he could not effectively apply them himself, were correct and have become powerful tools of modern neuroscience.

Brain↗
PubMed1994

Quantitative evaluation of neuronal loss in the dorsal hippocampus in rats with long-term pilocarpine seizures.

Systemic administration of the cholinergic agonist pilocarpine (350-400 mg/kg, i.p.) to rats induces acute behavioral and EEG status epilepticus followed by apparent complete neurological recovery. In rats receiving higher doses of pilocarpine (i.e., 380-400 mg/kg), recurrent seizures reappear 2-2.5 weeks later and continue to occur as long as the rats are kept alive. Stereological estimates of neurons in regions CA1, CA3 and the dentate granule cell layer in the dorsal hippocampus show a dose-dependent neuronal loss in the CA3 and CA1 subregions. The granule cell layer of the dentate gyrus is not affected. No progressive neuronal loss was observed in the regions studied after 3, 6 and 12 weeks during which the animals displayed spontaneous recurrent seizures. The temporal profile of the epileptic condition induced by pilocarpine and the resulting pattern of neuronal loss in the rat hippocampus are similar to those seen in many cases of human temporal lobe epilepsy. The neuronal loss is dose-dependent and primarily results from the acute pilocarpine-induced seizures as chronic seizures do not produce any measurable additional cell loss in the regions examined in the experimental model used in this study.

Animals↗
PubMed1994

Relationship between atrophy of the amygdala and ictal fear in temporal lobe epilepsy.

Viscerosensory and affective manifestations are often elicited by temporal lobe seizure discharges. They have been reproduced by amygdaloid stimulation in awake patients during stereotaxic exploration or neurosurgical procedures. They are not exclusively reproduced by stimulation of the amygdala, though most commonly they are evoked from it. Ictal fear is frequently, but not invariably, associated with a rising epigastric sensation, palpitations, mydriasis and pallor. We studied 50 patients (mean age 33 years) with intractable temporal lobe epilepsy (TLE): MRI volumetric measurements of amygdala and hippocampus were performed using a protocol previously described by our group (Watson et al., Neurology 1992; 42: 1743-50). All patients had extensive EEG investigation and at least two seizures recorded by video-EEG monitoring. Seventeen patients (34%) had a clear history of fear accompanied by a rising epigastric sensation as the initial manifestation of their habitual attacks. The amygdala volumes in this group were significantly (P = 0.001) smaller (mean 2131.6 mm3) compared with the volumes of the 33 patients without these symptoms (mean 2561.5 mm3). Both patient groups had smaller mean amygdala volumes compared with normal controls (mean 2828.2 mm3). Postoperative pathology correlated well with volumetric atrophy. In addition, we found that patients with more pronounced amygdaloid atrophy more commonly had prolonged febrile convulsions in early childhood and also more frequently secondarily generalized seizures. Results support the finding that ictal fear is related to pathology of the amygdala and that it, like the hippocampus, is an important substrate of TLE.

Adolescent↗
PubMed1994

Late-onset drop attacks in temporal lobe epilepsy: a reevaluation of the concept of temporal lobe syncope.

We report the clinical, radiologic, and EEG features of six patients with temporal lobe drop attacks (TLDA), all of whom underwent temporal resection. Postoperative follow-up of at least 1 year was available in all. TLDA were never the first manifestation but followed the onset of epilepsy after a long delay ranging from 7 to 43 years (mean, 24.4 years). Seizures were of unilateral temporal origin. In one patient, stereo EEG recording of TLDA showed rapid spread of the ictal discharge away from the temporal lobe in less than 1 second. Postoperatively, three patients were seizure free; one has had no TLDA but experiences sporadic auras; another, despite a reduction of more than 50%, continues to have complex partial seizures and TLDA; and the sixth has had sporadic secondarily generalized seizures upon reduction of antiepileptic medication. In conclusion, drop attacks may occur in temporal lobe epilepsy, usually long after the onset of epilepsy. They lead to increased disability and suggest a rapid spread of the ictal discharge and possible involvement of the pontine reticular formation rather than the presence of bitemporal foci or an extratemporal origin.

Adult↗
PubMed1993

Atrophy of mesial structures in patients with temporal lobe epilepsy: cause or consequence of repeated seizures?

We studied 70 epileptic patients by using magnetic resonance imaging volumetric measurements of amygdala (AM) and hippocampal formation (HF). Fifty patients presented with intractable temporal lobe epilepsy (TLE), 10 patients had focal extratemporal lobe epilepsy, and 10 had generalized epilepsy. In 91% of the 45 TLE patients without foreign tissue lesions, there was significant smallness of the AM and/or HF coinciding with the side of electroencephalographic seizure onset. No significant smallness or asymmetry was demonstrated in patients with focal extratemporal or generalized epilepsy. We performed a linear regression analysis, plotting the number of years of recurrent seizures and the estimated seizure frequency against the volumes of the AM and HF. There was no correlation between either of these two parameters and AM or HF volume (p > 0.9). There was also no correlation between the patient's age and volumetric measurements of AM or HF, nor did these measurements correlate with the occurrence of generalized seizures. On the other hand, patients with antecedent prolonged febrile convulsions in early childhood had significantly smaller AM and HF, compared with those without such a history (p < 0.001). The findings indicate that repeated seizures or longer duration of epilepsy do not cause increased atrophy of AM or HF that is measurable by volumetric magnetic resonance imaging.

Adolescent↗
PubMed1993

Clinical responses to electrical brain stimulation of the temporal and frontal lobes in patients with epilepsy. Pathophysiological implications.

The clinical responses elicited by electrical stimulation of discrete cerebral structures in the temporal and frontal lobes were studied in 75 patients undergoing pre-surgical evaluation using chronic intracerebral electroencephalographic recordings. Responses without after-discharge spreading beyond the site of stimulation included somatosensory, autonomic, thermoregulatory and viscerosensory phenomena, simple motor responses, some simple automatisms, changes in facial expression or voice tone, vocalizations, conscious confusion and experiential phenomena. Except for oro-alimentary automatisms, these responses were similar to the initial responses elicited by stimulations followed by a spreading after-discharge. Responses were most often obtained from limbic structures, sometimes from the temporal isocortex, and rarely from frontal sites (except for simple motor activity and some simple automatisms). Specific clinical responses could often be elicited from more than one site (74 out of 147), frequently even from non-contiguous areas in the same or both hemispheres. This suggests that the neuronal substrates responsible for the production of some of these phenomena are widespread neuronal matrices linked through connections which have become strengthened through repeated use as hypothesized by one of us [Gloor (1990), Brain, 113, 1673-1694]. Such a hypothesis could also account for the individually idiosyncratic nature of many of these responses.

Amygdala↗
PubMed1993

The human dorsal hippocampal commissure. An anatomically identifiable and functional pathway.

The hippocampal commissural system in the human brain was found to be similar to that of non-human primates. Three normal serially sectioned human brains were studied in coronal and sagittal sections. Morphological criteria that had been validated in experimental studies on the hippocampal commissures in monkeys (Amaral et al., 1984; Demeter et al., 1985; Lamantia and Rakic, 1990) were applied to the study of these human brains. It was found that while a further reduction in the ventral hippocampal commissure has taken place in human phylogeny leading to its near or total disappearance, the dorsal hippocampal commissure is well developed and represents a sizable fibre tract. It crosses the midline under the rostral portion of the splenium and the caudal part of the body of the corpus callosum. Its fibres as they travel between the splenium and the hippocampal formation attach themselves to the fornix and the inferior portion of the forceps major of the corpus callosum. In its morphology the human dorsal hippocampal commissure fully conforms to that reported in experimental tracer studies in the monkey (Amaral et al., 1984; Demeter et al., 1985). Depth electrode EEG recordings of temporal lobe seizures show, in some instances, a pattern of contralateral spread which strongly suggests that it occurred through the dorsal hippocampal commissure. This statement is based on a careful analysis of the different patterns of contralateral spread of seizure discharge in the light of the known anatomical connections of mesial temporal structures through both direct commissural pathways and through possible indirect ones involving subcortical structures or the frontal lobe. For seizure discharges originating in mesial temporal structures of one side with spread to the contralateral hippocampus before any involvement of the contralateral isocortex the dorsal hippocampal commissure is the only likely pathway of contralateral propagation. Alternative routes appear unlikely in the light of the known primate anatomy of the commissural and other connections of the temporal lobe. Thus humans, despite claims to the contrary (Wilson et al., 1987, 1990, 1991), seem to possess a functional dorsal hippocampal commissure. Some patterns of seizure spread observed in this study which seem to utilize the dorsal hippocampal commissure may be relevant for two phenomena that are of clinical interest: (i) pure amnestic seizures (Palmini et al., 1992); (ii) false lateralization of seizure onset in extracranial EEG recordings in the type III of contralateral seizure spread as defined in this study.

Adolescent↗