Search PubMed⌕ Search

Biomedical subjects

P Henry

Publications and source records attributed to P Henry.

At least 91 records · Page 5Linked to original sources

High-grade B-cell cerebral lymphoma in a patient with anti-myelin-associated glycoprotein IgM paraproteinemic neuropathy.

A 74-year-old woman with a sensory neuropathy and IgM M-protein monoclonal gammopathy of undetermined significance developed a fatal B-cell cerebral lymphoma. CSF protein immunofixation revealed intrathecal secretion of a paraprotein of the same heavy- and light-chain isotypes as the serum monoclonal component (IgM-lambda). Reactivation of Epstein-Barr virus was present in the lymphoma cells. Different factors may be involved in the preferential malignant development of the monoclonal B-cell clone within the CNS.

Aged↗

[Value of the study of somatosensory evoked potentials during surgical correction of scoliosis associated with syringomyelia. Apropos of 4 cases].

PURPOSE OF THE STUDY: The presence of a syringomyelia cavity increases the rate of neurological complications on the course of surgical treatment of scoliosis. We have evaluated the results of monitoring of somatosensory evoked potentials (SEP) in these situations. MATERIAL AND METHODS: Four patients presenting a scoliosis associated with syringomyelia have been operated through a posterior-approach with CD instrumentation. SEP monitoring was performed pre and intraoperatively. We studied the latency and the amplitude of P40. RESULTS: Preoperative SEP showed in all cases posterior spinal cord involvement (even without clinical manifestations). During monitoring, we noted in one case no variation. In one case a flattening of the response with normalisation within 5 minutes. In two cases a persistent flattening with normalisation within 10 and 15 minutes following modification of the instrumentation. In all cases, postoperative neurological status was identical to preoperative one. DISCUSSION: Preoperative SEP can make the diagnosis of posterior spinal cord involvement even when clinical status is normal. The extent of the preoperative SEP abnormalities may preclude the risk of intraoperative neurological complications. Intraoperative SEP can be performed with the same anesthetic protocol and the same technique used when operating idiopathic scoliosis. The results seem reliable. When alteration occur as for idiopathic scoliosis alteration of the amplitude appears earlier than alteration of the P40 latency. Restoration of normal responses appears later than in idiopathic scoliosis. CONCLUSION: SEP monitoring should diminish the risk for neurological complications in the course of surgical treatment of scoliosis associated with syringomyelia.

Adolescent↗

[Impact of controlling risk factors after myocardial infarction].

The relative risks of each factors and the benefits of their reduction after myocardial infarction are comparable to those observed in primary prevention. However, because of an overexposure to the risk, the absolute gains are five times greater. The impact of diet is one of the most important: in addition to the limitation of polyunsaturated fats and global calory intake, especially in cases of central obesity, the increase in dietary alpha-linolenic acid and in omega-3, has been shown to reduce the risk of myocardial infarction and mortality by up to 70%. Supplements of vitamins A and E could be useful. After infarction, the risks of an ex-smoker decrease rapidly by half and become comparable to those of non-smokers in 2 to 3 years. Physical exercise reduces cardiovascular mortality by 20-25% and contributes to better control of risk factors. The management of some psycho-physiological factors (reaction to stress, hostility) also gives encouraging results). A 10% reduction in total cholesterol leads to a 20% or more decrease in coronary events and a 10% reduction in mortality with a marked dose-response effect inciting to the reduction of its level to under 2 g/l. The progression of atherosclerosis delayed; early lesions, with the greatest risk of rupture and thrombosis, are stabilised and may even regress. A low HDL-c concentration should lead to more energetic reduction of LDL-c and control of smoking, obesity and sedentarity. Its association with hypertriglyceridaemia, glucose intolerance, hypertension and central obesity defines the syndrome of insulin resistance which multiplies cardiovascular risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

[Ischemic preconditioning: concept of endogenous myocardial protection].

Preconditioning is a temporary tolerance to ischaemia acquired by the myocardium after a short period of ischaemia. It results in the limitation of the infarct size induced by prolonged coronary occlusion. The mechanism of this cytoprotection remains poorly understood. The A1 adenosine receptors, the ATP-sensitive potassium channels and protein-kinase C seem to play prominent roles. The effects of preconditioning on the complications of ischaemia/reperfusion such as myocardial stunning, ventricular arrhythmias or decreased coronary reserve are not well known. Several studies suggest that the cytoprotection resulting from preconditioning could be applied to human myocardium and constitute a preventive anti-ischaemic therapy during coronary angioplasty, cardiac surgery or the conservation of transplant grafts.

Adaptation, Physiological↗

[Significance of polyglucosan bodies in neuropathology. Clinico-pathologic study of seven cases].

Seven observations, having in common an accumulation of polyglucosan bodies in the nervous system, are reported. In 2 cases of adult polyglucosan body disease, characteristic polyglucosan bodies were found on the peripheral nerve biopsies, and also on the cerebral biopsy in one of these patients who was demented. The 5 other cases presented medically intractable temporal lobe epilepsy. Recovery was obtained by a temporal lobectomy in which a massive accumulation of polyglucosan bodies was discovered. These personal observations are discussed with regard to other conditions characterized by accumulation of polyglucosan bodies in the nervous system. The non specificity of these formations is emphasized.

Adult↗

A review of educational developments with Brånemark osseointegrated oral implants in Australia and New Zealand 1992-1994. Part I: Treatment data for Australia and New Zealand.

This review should be read in conjunction with the Teams Day Conference review of 1992. This data further emphasises the trend in implant restoration that was becoming apparent at that time. However, the degree to which single tooth implant restorations now dominate clinical implant treatment is unprecedented. There is clear evidence of a progressive increase also in segmental and full arch bridgework, but minimal increase in overdenture restorations. The data also indicates that for the first time the number of males treated was greatest and that the maxilla was more frequently restored. This latter feature is no doubt closely linked with the emphasis given to single tooth restorations. This data, fully supports the inclusion of implant restoration into general and specialist dental practice.

Australia↗

A review of educational developments with Brånemark osseointegrated oral implants in Australia and New Zealand 1992-1994. Part II: Undergraduate, and postgraduate implant education in Australian and New Zealand dental schools.

A survey of Australian and New Zealand Dental Schools was carried out in 1993, aimed at assessing time allocation and curriculum content in relation to dental implants. Considerable variation was evident at both undergraduate and graduate levels. Continuing education courses in single-tooth implant surgery are available for general dental practitioners under carefully controlled circumstances. At the postgraduate level a formal University Diploma course in oral implants is now available at the University of Sydney. Dental educators must continue to react to the changing community scene in restorative dentistry, in terms of both need and demand. Educators must also be cognizant of the rapidity of change occurring in the area of implant dentistry. The provision of high-quality implant treatment and service is dependent on continual review of training and education at all levels of the dental profession.

Australia↗

Determination of spiramycin and neospiramycin in plasma and milk of lactating cows by reversed-phase high-performance liquid chromatography.

After chloroform extraction, the rapid and sensitive determination of spiramycin and neospiramycin can be performed with AASP-diol clean-up cartridges prior to reversed-phase C18 high-performance liquid chromatography. The limits of quantification of spiramycin in plasma and milk are 0.023 and 0.013 microgram/ml, respectively, and those of neospiramycin, are 0.058 and 0.006 microgram/ml, respectively. Application of the method to the analysis of plasma and milk samples obtained from pharmacokinetic studies is described. Spiramycin has a terminal half-life of 14.27 h in plasma and 34.59 h in milk, while neospiramycin has a half-life of 25.62 h in plasma and 105.85 h in milk.

Animals↗

[Cerebrovascular complications of non-bacterial thrombotic endocarditis: value of transesophageal echocardiography].

Non bacterial thrombotic endocarditis is a frequent cause of cerebrovascular complications in patients with cancer. Clinical features are often misleading and symptoms are hardly linked to valvular thrombosis in the absence of systemic embolism. We describe here a case mainly illustrating two aspects: clinical and neuroradiological manifestations of multiple distal brain infarcts and the value of transoesophageal echocardiography for the diagnosis.

Cerebral Infarction↗

Spontaneous and 5HT-induced cyclic contractions in superficial temporal arteries from chronic and episodic cluster headache patients.

Superficial temporal arteries (STAs) are abnormally dilated in the painful side during cluster headache (CH) attacks. We have assessed the possible dysfunction of these arteries by comparing in vitro the reactivity of STAs removed from the painful side of CH patients during a cluster of attacks with that of STAs from patients free of CH. The responses to KCl and norepinephrine (NE) of both types of arteries were similar. Serotonin (5HT) induced a classical dose-dependent constriction in arteries from non-CH patients, but systematically triggered rhythmic contractions in arteries from episodic CH patients. Arteries from chronic CH patients also showed spontaneous rhythmic contractions. In both cases, this activity was stopped by calcitonin gene-related peptide (CGRP) but, even in the presence of CGRP, it could be restored by low concentrations of 5HT. Thus, 5HT, unlike NA, can trigger rythmic activity in STAs of CH patients and may play a major role in CH through abnormal smooth muscle cell reactivity.

Adult↗

Do potassium channel openers compete with ATP to activate ATP sensitive potassium channels?

Potassium channel openers are a class of chemically heterogeneous compounds that produce vasodilatation by opening vascular smooth muscle potassium channels. Using various configurations of the powerful patch clamp technique, the molecular pharmacology of potassium channel openers has been largely explored in different cellular systems. These studies have revealed that the primary molecular target for potassium channel openers is this class of potassium channel proteins that close under the influence of intracellular ATP and have thus been named ATP sensitive potassium channels. Direct recordings of unitary ATP sensitive potassium channels in cell detached membrane patches support the view that potassium channel openers compete with intracellular ATP to prevent channel inhibition. However, there also exists experimental evidence that contradicts the competition hypothesis and suggests the involvement of phosphorylation-dephosphorylation mechanisms. The aim of the present article is to review experimental data that support, or inversely, contradict the potassium channel opener-ATP competition theory.

Adenosine Triphosphate↗

Healthy working and performance management. A discussion of the approach and a report on a survey of NHS organizations.

Achieving high performance in an organization is a complex business. Most approaches are too piecemeal, unidimensional or iatrogenic. Healthy working is an approach to managing performance that attempts to overcome these problems by aiming, in a holistic manner, to harmonize those factors which affect, either separately or jointly, individual physical, mental and emotional health and individual and organizational performance. The approach is based on a set of values and a series of steps. The first step has to be establishing an information base-line--the four key indicators. A survey was undertaken by PBS to establish the availability and usefulness of data in NHS organizations; summarizes some of the issues raised. Although a worryingly small number keep useful data or produce useful information, much can be done in making critical links if available data is fully used.

Employee Performance Appraisal↗

Prevalence of Parkinson's disease in the elderly: a population study in Gironde, France.

We investigated the prevalence of Parkinson's disease in a representative sample of the elderly population living in the Gironde département, France. Among 3149 people over age 65, the prevalence ratio for Parkinson's disease was 1.4%, without significant difference between men and women. We found that age-specific prevalence ratios increased with age from 0.5% in the age group 65 to 69 to 6.1% in individuals over age 90. This age pattern is consistent with that found in other population-based studies. Interestingly, the slope of age-specific prevalence ratios for Parkinson's disease was similar to that previously reported for Lewy bodies. Our study showed that a high proportion (42%) of Parkinson's disease cases in elderly subjects living in institutions were undiagnosed.

Aged↗

Effects of hydrocortisone on pulsatile pituitary glycoprotein secretion.

During states of stress, hypothalamic-pituitary-thyroid and hypothalamic-pituitary-gonadal function can be suppressed. One putative mediator of this stress response may be glucocorticoids, which have widespread effects on thyroid and gonadal function. To characterize dynamic pituitary glycoprotein secretion during glucocorticoid administration, 24-h TSH, LH, FSH, and alpha-subunit pulses were measured in 10 healthy young subjects on 3 occasions: 1) at baseline, 2) during infusions of 100 mg hydrocortisone (HC) over 24 h, and 3) during infusions of 300 mg HC over 24 h. These HC infusions led to serum cortisol levels similar to the endogenous cortisol levels seen in moderate and severe stress. Both HC infusions had profound rapid effects on TSH levels, decreasing TSH pulse amplitude by 60% and abolishing the nocturnal TSH surge. However, TSH pulse frequency was unaltered. In contrast, HC infusions did not change mean or pulsatile LH, FSH, or alpha-subunit secretion. These results suggest that stress levels of cortisol acutely suppress TSH secretion at the pituitary level, with little effect on the TSH pulse generator. On the other hand, the effects of stress and/or hypercortisolism on the gonadal axis may require higher cortisol levels, more prolonged exposure, or other mediators of the stress response.

Adult↗

[Mechanisms of atrial fibrillation: recent advances].

Atrial fibrillation (AF) is due to the presence of multiple reentry pathways. Although this mechanism has been known for some time, new information has recently been acquired about the factors of atrial vulnerability and the conditions of myocardial alteration. There are two main factors of atrial vulnerability: intra-atrial conduction defects and abnormalities of the refractory periods. In addition, the concept of critical mass and the influence of the autonomic nervous system have to be taken into consideration. The abnormalities of the refractory periods liable to increase atrial vulnerability are their shortening, spatial dispersion and poor adaptation to the heart rate. All these changes may be demonstrated at cellular level. The product of the intra-atrial conduction velocity and the duration of the refractory period defines the wave length. The risk of developing reentry pathways increases as the wave length shortens. Moreover, the more the atrium fibrillates, the greater will be the decrease of the refractory periods, atrial fibrillation giving rise to atrial fibrillation. Histological lesions of the atrial tissue may be demonstrated, even in the absence of underlying cardiac disease. They mainly consist of fibrosis, fatty degeneration and myocytic hypertrophy. In the long-term, atrial fibrillation leads to a number of structural abnormalities of the atrial, and sometimes ventricular tissues, progressing to cardiomyopathy in some cases.

Action Potentials↗

Apomorphine increases blood glucose concentrations in Parkinson's disease.

Data from studies indicate that blood glucose levels may be influenced by stimulation of central D1 and D2 dopamine receptors. This is modulated by central dopamine receptor status. We studied apomorphine-induced increase in blood glucose levels in Parkinson's disease compared with those in Parkinsonian syndromes unresponsive to dopaminergic drugs. Results indicate that apomorphine-induced blood glucose level increases are significant only in Parkinson's disease. As in the animal, this could possibly be explained by central dopamine receptor status.

Aged↗