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Biomedical subjects

F Martin

Publications and source records attributed to F Martin.

At least 739 records · Page 41Linked to original sources
PubMedDate not supplied

Long latency event-related potentials (P300) in gifted children.

In children, P3 latency decreases with increasing age. This decrease could be linked with the maturation of cognitive processes. According to this hypothesis, event-related potentials P3 were recording in gifted children to research an electrophysiological correlation with the mental precocity. Auditory long latency event-related potentials were recorded in 10 gifted children (IQs over 140) and 23 control subjects. The part of variance related to age was extracted by comparing deviations from regression line as a function of age. Stimulus-evoked N1 component latency was not statistically different in the two populations. Event-related P3 component latency was significantly shorter in the gifted children at Cz (P < 0.05). Inter-peak interval N1-P3 was significantly shorter at all three recording sites (P < 0.01 at Fz and CZ, P < 0.02 at Pz). These results suggest a relationship between the P3 component and cognitive ability in children.

Acoustic Stimulation↗
PubMedDate not supplied

Chronic alcoholic skeletal myopathy--common and reversible.

Although musculoskeletal symptoms are common in alcoholics, little is known of the prevalence of muscle pathology in this group. Quadriceps muscle biopsies were performed in 151 alcoholics (105 men). Ninety patients showed type 2 fibre atrophy predominantly affecting the type 2b anaerobic glycolytic fibres. In contrast, 7 biopsies revealed some muscle necrosis and only 1 patient had acute rhabdomyolysis. Amongst those alcoholics with muscle atrophy the quantity of alcohol consumed in the year prior to biopsy correlated significantly with the severity of the atrophy. Atrophy was not associated with vitamin B12, folate, pyridoxine, riboflavin or thiamine deficiencies. Although patients with severe liver disease, peripheral neuropathy or malnutrition were more likely to have muscle atrophy, nerve conduction studies showed that atrophy and neuropathy each occurred independently. Sequential studies in abstaining alcoholics showed a significant improvement within 3 months and often complete recovery within a year. Continued consumption of alcohol was associated with persistence or progression of the atrophy. This study shows that reversible type 2b muscle fibre atrophy is a frequent finding in alcoholics and suggests that it is directly related to alcohol consumption and is not a consequence of malnutrition, vitamin deficiency or peripheral neuropathy.

Adenosine Triphosphatases↗
PubMedDate not supplied

P300 in heavy social drinkers: the effect of lorazepam.

The P300 component of the event-related potential (ERP) and reaction time (RT) were recorded during a simulated driving task using an oddball paradigm. ERPs and RTs were recorded from heavy social drinkers (n = 11) and low social drinkers (n = 11). A pharmacological challenge (lorazepam-ATIVAN) was administered to both groups in a double-blind procedure. In both groups, P300 amplitude was reduced and RT was increased by the presence of lorazepam; however, heavy social drinkers had longer latency P300 than low social drinkers regardless of the drug condition. The P300 amplitude results are consistent with reduced information processing being induced by lorazepam, or with reduced effectiveness of the eliciting stimuli. On the other hand, the P300 latency results suggest that P300 latency may reflect deficits in information processing induced by alcohol abuse or may have preceded the alcohol abuse. The P300 latency results are consistent with heavy social drinkers occupying an early point on the hypothesized continuum of alcohol-related brain damage.

Adult↗
PubMedDate not supplied

Computerized localization of brain structures in single photon emission computed tomography using a proportional anatomical stereotactic atlas.

An accurate identification of cerebral structures is necessary to perform quantification of single photon emission computed tomography (SPECT). We have developed an anatomical localization system that accounts for individual brain shapes and sizes by using the Talairach proportional grid system. The locations of the commissural lines, which define the stereotactic coordinate system, are calculated from the external landmarks provided by the canthomeatal line. This is validated on MRI images. When applied to SPECT data, the use of a neuroanatomical atlas data along with the automaticity of the processing guarantees a high degree of objectivity and inter-observer reproducibility.

Anatomy, Artistic↗
PubMedDate not supplied

[Peliosis hepatis in dermatomyositis treated with azathioprine and corticoids].

We report a case of peliosis hepatis in a 47-year old male patient with dermatomyositis treated with azathioprine and corticosteroids. Three months after the combined treatment was initiated, the patient developed right thoracic herpes zoster, agranulocytosis and liver enlargement with signs of portal hypertension. Needle biopsy of the liver revealed peliosis. Azathioprine was withdrawn. The clinical and laboratory abnormalities disappeared progressively. The main causes of peliosis hepatis are considered. Up to now, azathioprine had been held responsible for peliosis hepatis only in renal transplant recipients.

Azathioprine↗
PubMedDate not supplied

[False hyperphosphoremia in multiple myeloma. Interference of monoclonal immunoglobulin G with the determination of blood phosphorus level].

A case of pseudohyperphosphataemia detected in a male patient with multiple IgG myeloma is reported. Phosphataemia, measured by a technique without previous deproteinization, reached 5.66 mM before any treatment and varied with treatment-induced changes in monoclonal immunoglobulin levels. Conversely, normal phosphataemia levels were found in blood samples taken before and after treatment when serum was deproteinized. This pseudohyperphosphataemia resulted from an increase in optic density due to interference between monoclonal immunoglobulin and the molybdic reagent used to determine phosphataemia. A retrospective investigation yielded three similar cases: two in patients with myeloma and one in a patient with non-myelomatous monoclonal dysglobulinaemia. A brief prospective study showed that this phenomenon was relatively frequent, as it was found in 2 out of 9 patients with monoclonal immunoglobulin (IgG in all 9 cases). These data indicate that the finding of marked hyperphosphataemia in subjects with monoclonal dysglobulinaemia should always prompt a control assay performed on deproteinized blood.

Electrophoresis↗
PubMedDate not supplied

[Cutaneous plasmacytoma: review of the literature apropos of a case].

Extramedullary plasmocytomas are ubiquitous plasmocytic tumours which are principally located in bones and mucosae but rarely found on the skin. Clinically, they present as purplish-blue cutaneous nodules or, less frequently, as papular or urticarial eruptions. The diagnosis rests on histology and immunostaining. Cutaneous plasmocytomas are usually divided into two types: (1) primary plamocytomas which occur in the absence of myeloma, present as solitary or multiple skin tumours, accompanied or not by monoclonal gammopathy, and have an imperfectly known course and prognosis; (2) secondary plasmocytomas--a case of which is reported here--which appear in the course of a large tumoral mass myeloma and have a very poor prognosis.

Aged↗
PubMedDate not supplied

[Multiple sclerosis associated with biological symptoms of systemic lupus erythematosus. A case with anatomical study].

A clinical history typical of multisclerosis began in a 20-year old man with transient, then permanent manifestations involving the optic tract and the pyramidal, extrapyramidal and cerebellar systems. The patient died at the age of 62, at the end-stage of a complex clinical situation which included paraplegia, bilateral cerebellar syndrome, optic nerve atrophy, epileptic seizures and dementia. When the patient was 54 years old, laboratory findings suggestive of systemic lupus erythematosus (SLE) were discovered, namely: antinuclear, native anti-DNA, anti-Sm antibodies, circulating anticoagulant, cryoglobulinaemia and low complement level. These abnormalities persisted up to the patient's death, 8 years later, without any non-neurological sign of SLE. Post-mortem examination showed lesions of focal demyelination characteristic of multiple sclerosis, but no evidence of cerebral or extracerebral SLE. This case raises the problem of borderlines or associations between systemic lupus erythematosus and multiple sclerosis. In our case, as in other cases of "lupoid sclerosis" reported in the literature, there was a frank and isolated elevation of serum IgM levels.

Adult↗
PubMedDate not supplied

The effect of lorazepam on long-term verbal recall in heavy and light social drinkers.

Two experiments investigated long-term verbal memory performance in groups of 20-year-old heavy (HSDs) and light social drinkers (LSDs), in the presence and absence of a pharmacological challenge (lorazepam 2 mg). In Experiment 1 (n = 13), a verbal learning task was presented visually and it was found that lorazepam significantly impaired delayed verbal recall performance in both groups. Experiment 2 (n = 14) assessed the effect of presenting the verbal learning task in the auditory compared to the visual modality. Both groups' performance on the delayed trials of the visually presented task was reduced in the lorazepam treatment. However, in the auditory presented task, lorazepam reduced 30-min delayed recall performance in the HSDs but not in the LSDs. The differential effect of lorazepam on HSDs compared to LSDs on delayed recall performance when material is presented in the auditory modality may suggest that frequent heavy social drinking results in changes in CNS functioning.

Adult↗
PubMedDate not supplied

Development of male contraceptive vaccine--a perspective.

This paper reviews the recent advances that have occurred in the area of development of a male contraceptive vaccine. The vaccine candidates considered for review are hormone/hormone receptor-based proteins including luteinizing hormone-releasing hormone (LHRH)/LH, follicle stimulating hormone (FSH), as well as LH and FSH receptor proteins. The review also highlights the advances in our basic understanding of gonadotrophin action which have led to development of these vaccines. Focus is mainly on studies in the non-human primate which may be directly relevant to projected studies in the human. The data indicate that the vaccines are well tolerated by the primate (including the human based on limited data) and do not give rise to any known toxic symptoms or immediate health hazards. The response to the immunogen has been uniform and it may be possible to increase antibody titres as well as prolong the immune response by adding acceptable immune stimulators to the adjuvant cocktail and developing better immunization schedules or immunogen delivery systems. Contraceptive vaccines for the male are a feasible proposition and attention should now be focussed on evaluating carefully the bioefficacy of antibodies raised to recombinant ovine FSHbeta or FSH receptor protein fragments in both human and non-human primates. The advantage of the FSH/FSH receptor over the LHRH/LH-based vaccine lies in the fact that the former does not require an exogenous testosterone supplement to maintain accessory gland function, libido etc. The LHRH/LH-based vaccine results in azoospermia, while the FSH vaccine causes the production of low numbers of poor quality spermatozoa which are incapable of impregnating cycling females.

Amino Acid Sequence↗
PubMedDate not supplied

The somatics of psyche: structural neuromorphometry of bipolar disorder.

Many neuroimaging investigations report structural differences in subjects with bipolar disorder; however, conflicting results are common in the limited number of available investigations. Thus, the structural correlates of bipolar disorders remain poorly understood. The authors reviewed the early investigations using computed tomography and examined gross structural differences, such as cerebral atrophy, ventricular enlargement, or cerebellar atrophy. Many of these investigations report significant differences in these features compared with controls, whereas others found no such differences. More recent magnetic resonance imaging (MRI) investigations have employed increasingly sophisticated imaging and research methodologies, allowing for the quantitative examination of specific brain regions. Because neuropsychological and functional studies suggest abnormalities in frontal, temporal and subcortical regions, many investigators have focused their MRI neuromorphometric studies on these temporal limbic structures. However, the number of investigations examining each of these regions remains small, and conflicting results continue to be reported. It seems clear that for many brain regions, the structural changes from normal may be subtle, and that the differences in the reported studies may be due to differences in research methodologies between studies and across centers.

Amygdala↗
PubMedDate not supplied

Migration of trace elements from pyrite tailings in carbonate soils.

In the carbonate soils contaminated by a toxic spill from a pyrite mine (Aznalcóllar, southern Spain), a study was made of a thin layer (thickness = 4 mm) of polluted soil located between the pyrite tailings and the underlying soil. This layer, reddish-yellow in color due to a high Fe content, formed when sulfates (from the oxidation of sulfides) infiltrated the soil, causing acidification (to pH 5.6 as opposed to 8.0 of unaffected soil) and pollution (in Zn, Cu, As, Pb, Co, Cd, Sb, Bi, Tl, and In). The less mobile elements (As, Bi, In, Pb, Sb, and Tl) concentrated in the uppermost part of the reddish-yellow layer, with concentration decreasing downward. The more mobile elements (Co, Cd, Zn, and Cu) tended to precipitate where the pH was basic, toward the bottom of the layer or in the upper part of the underlying soil. The greatest accumulations occurred within the first 6 mm in overall soil depth, and were negligible below 15 mm. In addition, the acidity of the solution from the tailings degraded the minerals of the clay fraction of the soils, both the phyllosilicates as well as the carbonates. Also, within the reddish-yellow layer, gypsum formed autigenically, together with complex salts of sulfates of Fe, Al, Zn, Ca, and Mn, jarosite, and oxihydroxides of Fe.

Hazardous Substances↗
PubMedDate not supplied

Möbius' syndrome: features and etiology.

PURPOSE: To review the clinical features and possible aetiology of all cases of Möbius' syndrome presented at the Royal Alexandra Hospital for Children in Sydney, Australia, from 1963 through 1995. METHODS: All charts of patients suffering from Möbius' syndrome were reviewed, and each patient was thoroughly assessed by a geneticist and a pediatric ophthalmologist. RESULTS: Patterns of systemic and ocular clinical features became evident. Of 23 patients in the series, 10 (43%) had a history significant events in utero. CONCLUSIONS: All patients suffering from Möbius' syndrome require thorough assessment by a multidisciplinary team including a geneticist or pediatrician and a pediatric ophthalmologist. Significant vascular events of pregnancy may explain some cases of fetal vascular disruption to the brainstem.

Abducens Nerve↗
PubMedDate not supplied

[Pancreatic fistula following duodenocephalopancreatectomy with Wirsung occlusion].

AIMS: The large number of operative procedures used to carry out an enteropancreatic anastomosis after pancreatoduodenectomy definitely mirror all difficulties and problems brought about by anastomosis. The aim of this study is to evaluate the clinical results and complications concerning the pancreatic remnant after pancreatoduodenectomy with Wirsung duct occlusion. METHODS: From 1984 to 1999, 134 patients were treated by pancreatoduodenectomy with Wirsung duct occlusion using synthetic resins. A consecutive series of 95 patients without mortality operated in the last decade were regularly followed by ultrasound examination and CT-scan as well as by serial measurements of the volume and the amylase content of the drainage fluid. RESULTS: No operative mortality occurred. Two events could be evidenced after this kind of operation: 1) the presence of an asymptomatic fluid collection at the side of the pancreatic section with spontaneous absorption (31 patients: 32.6%); 2) the occurrence of a pancreatic fistula (5 patients: 5.3%): in three cases (3.2%) a fistula jejunostomy was required. CONCLUSIONS: The evidence of the mild clinical relevance of complications and the low percent rate of reoperations enables to state that this method can be highly reliable.

Adult↗
PubMedDate not supplied

[Monoclonal antibody SPan-1 in the diagnosis of exocrine pancreatic adenocarcinoma].

The great progress made in imaging techniques over the past few years has not resulted in an improvement in terms of earlier diagnosis of exocrine pancreatic cancer. The search for a non-invasive diagnostic tool, capable of yielding an early diagnosis, has led to the development of a series of serum tumour markers. This article discusses the clinical evaluation of SPan-1 and its comparison with established markers such as CA 19.9, CEA, TPA and CA 242. The markers were tested in preoperative serum samples collected from 46 patients operated on for ductal carcinoma of the pancreas, 20 patients with chronic pancreatitis and 23 patients with other digestive neoplasms. Sensitivity, specificity and diagnostic accuracy for pancreatic cancer were as follows: [table: see text] The antigenic determinant recognised by monoclonal antibody SPan-1 is high in sera of patients with exocrine pancreatic cancer. SPan-1 may be another useful, reliable serum marker in detecting this neoplasm, but this study indicates that SPan-1 does not greatly improve the diagnostic accuracy achieved with CA19.9.

Adenocarcinoma↗