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Biomedical subjects

J Raymond

Publications and source records attributed to J Raymond.

At least 145 records · Page 8Linked to original sources
PubMed1993

Pulsatile tinnitus and dural arteriovenous fistula of the transverse sinus.

A case of dural arteriovenous fistula of the transverse and sigmoid sinus presenting with a pulsatile tinnitus is described. On the basis of this demonstrative case, we review the clinical presentation, pathogenesis, diagnostic imaging and principles of treatment of this disease. Emphasis is put on the importance of careful diagnostic evaluation because of potential cerebrovascular complications associated with dural fistulas.

Arteriovenous Fistula↗
PubMed1992

Identification of neuron subpopulations in the rat vestibular ganglion by calbindin-D 28K, calretinin and neurofilament proteins immunoreactivity.

Immunocytochemical and morphometric analyses were combined to demonstrate the presence of neuron subpopulations in the rat vestibular ganglion. Monoclonal antibodies reacting with neurofilament proteins (NF), calbindin-D 28K (CaBP) and calretinin (CaR) were used. Three subpopulations were identified: (1) CaBP- and CaR-positive neurons were the largest neurons (16%) and they were also highly NF-immunoreactive; (2) exclusively NF-positive neurons; (3) unlabelled neurons, representing about two-thirds of the population.

Animals↗
PubMed1992

Prevention of pre-PCR mis-priming and primer dimerization improves low-copy-number amplifications.

A Hot Start Polymerase Chain Reaction (PCR) entails the withholding of at least one reagent from the reaction mixture until the reaction tube temperature has reached 60-80 degrees C. Hot Start amplification with an AmpliWax vapor barrier uses a layer of solid wax to separate the retained reagent(s) and the test sample from the bulk of the reagents until the first heating step of automated thermal cycling melts the wax and convectively mixes the two aqueous layers. Wax-mediated Hot Start PCR greatly increases the specificity, yield, and precision of amplifying low copy numbers of three HIV targets. In the presence of 1 microgram of human placental DNA (1.6 x 10(5) diploid genomes) the specificity improvement entails considerable to complete reduction in the amplification of mis-primed sequences and putative primer oligomers. When mis-priming is negligible, the procedural improvement still suppresses putative primer oligomerization. Hot Start PCR with an AmpliWax vapor barrier permits routine amplification of a single target molecule with detection by ethidium stained gel electrophoresis; nonisotopically visualized probing suffices for confirmation. The improved amplification performance is evident for target copy numbers below approximately 10(3).

Base Sequence↗
PubMed1992

Underestimation of the incidence of measles in a population of French children.

Data on titres of specific antibodies against measles virus and information given by families and physicians were analysed in 133 vaccinated and 117 unvaccinated children. Only 2 of the 133 vaccinated children reported a history of measles, while 131 had detectable levels of antibodies. Measles antibodies were detected in 102 (87.2%) of the unvaccinated children, but a history of measles diagnosed clinically by a physician was reported in only 42 of them. These findings suggest that subclinical cases of measles are possible and contribute to the high circulation of the measles virus in the child population in France.

Adolescent↗
PubMed1992

Absence of intrathecal synthesis of some interferon-alpha subtypes in bacterial meningitis.

Sixty-five cerebrospinal fluid (CSF) samples from 54 infants and children with bacterial meningitis were analyzed for the presence of interferon (IFN)-alpha with a biologic assay. Of the 65 samples, 3 were positive (2-4 IU/mL) and only 1 of 56 collected early was at 4 IU/mL. These results suggest that some subtypes of IFN-alpha already reported as present in viral infections of the central nervous system are not detected in bacterial meningitis by our IFN assay. This difference may be helpful in differentiating bacterial from viral infections and also in evaluating the quality of the virologic investigation; moreover, the rarity of IFN-gamma in CSF in bacterial meningitis needs further investigation to understand its role in the pathogenesis of the disease.

Child↗
PubMed1992

Renal arterial stenosis: slowed systole in the downstream circulation--experimental study in dogs.

To test the effect of stenosis of the renal artery on the downstream intrarenal blood flow, a snare was placed around the renal artery in 10 dogs and compressed to create stenosis while Doppler curves were obtained from interlobar arteries. Pulsed Doppler examination of the segmental and interlobar arteries was performed by means of placement of a 7.5-MHz mechanical sector transducer directly on the surface of the kidney. The following calculations were made: degree of stenosis (evaluated with aortography), acceleration index (AI) (the acceleration of systole), and resistive index. The Doppler measurements were compared with findings on angiograms. The AI for normal arteries ranged from 2.2 to 4.3, and for arteries with 75% or greater stenosis, from 1.0 to 1.3. Systolic peaks disappeared as near occlusion was achieved. These changes were reversible within seconds of release of the arterial snare. Such change is identical to change in the pulsus tardus and parvus waveforms seen in both acute and chronic severe stenosis of the renal artery in humans.

Animals↗
PubMed1992

[Immunity to and incidence of measles in a population of Parisian children].

BACKGROUND: Measles remains prevalent in France despite the development of nationwide vaccination program. This study evaluates measles immunity and correlates it with active immunization. MATERIAL AND METHODS: A total of 250 (131 boys and 119 girls) French children, aged 2 to 15 years, seen as outpatients in our hospital, were studied from 1.01.90 to 1.06.91; 133 had received live measles vaccine during the 2nd year of life, the 117 others were not vaccine-protected. Evaluation included medical records, specially those concerning past-history of measles or measles-like diseases and immunizations. Measles IgG and IgM antibodies (ELISA) were looked for in all 250 children. RESULTS: 102 of the 117 children who were not vaccine-protected had a detectable antibody titer. 42 of these 102 had a history of measles, before the age of 5 years in 30, between 5 and 10 years in 9 and after the age of 10 years in 3. Only 4 of the 70 children aged over 10 years and not vaccine-protected had no detectable antibodies. 131 of the 133 actively immunized children had detectable antibodies. CONCLUSIONS: Measles is probably more frequently subclinical than was believed until now. Its relative frequency in France in children who had not received the live vaccine explains the high percentage of those aged over 10 years who had detectable antibodies and the relatively low incidence of the disease in teenagers and young adults.

Adolescent↗
PubMed1992

Improved food intake and reduced nausea and vomiting in patients given a restricted diet while receiving cisplatin chemotherapy.

Administration of cisplatin alone or in combination with other cytotoxic agents commonly produces intractable nausea and vomiting, which is currently controlled through high-dose antiemetic drugs. However, patients often refuse continued therapy because of suboptimal control of nausea and vomiting and substantial decline in nutritional status. In this pilot study, 19 patients receiving cisplatin were evaluated for nausea and vomiting, amount of food intake, and subjective assessment of well-being. The study group received a colorless, odorless, predetermined meal three times daily; the meal included cottage cheese, apple sauce, vanilla ice cream, and other selected foods. Control-group patients selected their own meal. Study-group patients exhibited higher overall food intake, decreased nausea and vomiting, and a higher scored estimation of well-being. The findings of this preliminary study indicate that the study diet helps provide nutrition care to cancer patients receiving cisplatin chemotherapy and helps create an atmosphere where the patient believes he or she has some control in the treatment outcome.

Adult↗
PubMed1991

Plasticity mechanisms in vestibular compensation in the cat are improved by an extract of Ginkgo biloba (EGb 761).

The effects of administration of an extract of Ginkgo biloba (EGb 761) on vestibular compensation was studied in unilateral vestibular neurectomized cats. This experimental model of CNS plasticity was investigated by using behavioral tests (postural disorders compensation, locomotor balance recovery), electrophysiological (spontaneous and evoked neck muscle activity) and neurophysiological (spontaneous firing rate recovery of deafferented vestibular cells) recordings, and immunocytochemical methods (synaptic loss and synaptic reoccupation within the deafferented vestibular nuclei). In all experiments, EGb 761 was administered over 30 days at daily doses of 50 mg/kg IP. The results showed a faster recovery in the EGb-treated group of cats as compared to an untreated control group. EGb administration strongly accelerated postural and locomotor balance recovery. Concomitantly, spontaneous neck muscle activity, vestibulo-collic reflexes and spontaneous firing rate of vestibular units located on the lesioned side were restored earlier. Morphological correlates characterized by a more rapid synaptic reoccupation were found in the deafferented medial vestibular nucleus by means of immunoreactive labelling using an antibody against a synaptic vesicle-associated protein (synaptophysin), but they displayed a longer time-constant in comparison with the behavioral and neurophysiological data. These results clearly demonstrate that EGb 761 acts on recovery mechanisms considered as key processes in vestibular compensation. They suggest that this substance would possess neurotrophic and/or neuritogenic properties improving functional recovery after CNS injury.

Animals↗
PubMed1991

Immunoturbidimetric assay for estimating free light chains of immunoglobulins in urine and serum.

An immunoturbidimetric assay for the assessment of free kappa and lambda light chains of immunoglobulins was developed using a commercial polyclonal antiserum with reactivity towards epitopes on the light chains, which are not expressed when they are bound to heavy chains. The assay, on a centrifugal analyser, is simple and rapid. The limit of detection is 5 mg/l of free light chain, with an assay range of 5-120 mg/l, intrabatch precisions from 1.5-6.4%, and interbatch precisions from 6.5-8.9%. The assay was only slightly less sensitive than colloidal gold staining of cellulose acetate electrophoreses for the detection of Bence-Jones protein in urine. For the serial monitoring of response to chemotherapy in patients with myeloma, the assay correlated well with serum paraprotein estimates obtained by densitometric scanning of Ponceau stained cellulose acetate electrophoreses, but not with serum beta-2 microglobulin measurements, even after correction for the effects of creatinine. These assays may prove to be of use for the monitoring of tumour response in the treatment of Bence-Jones myeloma.

Antibodies, Neoplasm↗
PubMed1991

[A rapid bacteriologic method for the diagnosis and surveillance of nosocomial pneumopathies].

The authors report a rapid quantitative culture of endotracheal aspiration samples in mechanically ventilated children. There was a good correlation (94.7%) between clinical and radiographic features of pneumonia and a cutoff point of 10(5) cfu.ml-1. The sensitivity of this rapid quantitative culture was 85% when compared with usual quantitative culture.

Bacteriological Techniques↗
PubMed1990

Health risk behaviours and ethnicity in Hawaii.

This study has examined the relationships of health-related behaviours to sociodemographic factors with special emphasis on ethnicity in Hawaii. Behavioural variables investigated were non-use of car seat belts, overweight, physical inactivity, smoking, heavier alcohol use, and driving while intoxicated. Sociodemographic factors considered were ethnicity, island, sex, age, education, employment status, marital status, and household income. Major ethnic groups studied were Caucasians, Hawaiians including part-Hawaiians, Chinese, Filipinos, and Japanese. The relationships of ethnic factors with the behavioural characteristics were studied by logistic regression after fitting significant non-ethnic sociodemographic variables. Multiple risk behaviour was investigated by canonical correlation analysis. Different behavioural factors were found to be associated with different sets of non-ethnic socioeconomic variables. There were significant ethnic differences in individual at-risk behaviours except for driving while intoxicated. Overweight was most prevalent among Hawaiians followed by Caucasians. Caucasians and Hawaiians were at higher risk for non-use of seat belts, cigarette smoking, and heavier alcohol use compared to Chinese, Filipinos, and Japanese. Orientals were physically less active than Caucasians and Hawaiians. Implications of the observed ethnic differences are discussed.

Demography↗
PubMed1990

Comparison of high-resolution computed tomography with discography in the evaluation of lumbar disc herniations.

After failure of conservative treatment, 100 patients with symptoms suggestive of lumbar herniated nucleus pulposus (HNP) but without objective deficits were investigated both by high-resolution CT (without intravenous or intrathecal contrast) and by discography. The L4-L5 and L5-S1 discs were investigated by both techniques in all patients. In addition, the L3-L4 disc was investigated in 20 patients. The 220 investigated discs were sorted out into 6 CT categories according to morphologic and technical criteria. They were also classified into 3 discographic groups according to morphologic and clinical criteria. Based on morphologic considerations alone, the false-negative CT rates varied from 0 to 64% and the false-positive rates varied from 0 to 19%, depending on the category under consideration. Based on both morphologic and clinical consideration, the false-negative CT rates varied from 34 to 57% and the false-positive CT rates varied from 23 to 50%. Thus, high-resolution CT does not constitute an adequate means of investigation for this category of patients and discography appears justified before considering any form of radical therapy.

Adult↗
PubMed1990

Presence of gamma interferon in human acute and congenital toxoplasmosis.

The production of gamma interferon in acute acquired and congenital toxoplasmosis was studied. Gamma interferon was produced at significant titers (P less than 0.001) in the course of both congenital toxoplasmosis and acquired toxoplasmosis at an early stage of infection, when Toxoplasma gondii was multiplying. Its presence in fetal blood was correlated with the positive inoculation of fetal blood or amniotic fluid into mice (95%). The data suggest that the fetus is able to synthesize gamma interferon as early as week 21 of pregnancy. This test, easily and rapidly performed, could be included among those useful for diagnosing fetal toxoplasmic disease.

Acute Disease↗
PubMed1990

Stimulation of radiation-impaired plasminogen activator release by phorbol ester in aortic endothelial cells.

Ionizing radiation has been reported to affect the fibrinolytic activity of exposed tissue. With cultured bovine aortic endothelial cells, radiation suppresses the release of plasminogen activator to the conditioned media, with a concomitant increase in intracellular plasminogen activator. Thus study was undertaken to determine whether radiation-impaired plasminogen activator release can be modified by phorbol ester. We exposed cultured bovine aortic endothelial cells to a sterilizing dose of 10 Gy of gamma-rays and found the treatment led to cell injury, as evidenced by an increased release of prelabeled chromium, and to a reduction of plasminogen activator in the conditioned media with elevated intracellular plasminogen activator in irradiated cells. Phorbol ester enhanced plasminogen activator activity in both sham-irradiated and irradiated endothelial cells. It was interesting to note that the increased plasminogen activator in phorbol ester-stimulated sham-irradiated cells was largely retained inside the cell, while it was released to the conditioned media in irradiated cells. Apparently, altered plasminogen activator activity of radiation-sterilized endothelial cells can be modified by exogenous stimuli.

Animals↗
PubMed1990

State and federal reimbursement for home nutrition support.

Dietitians offer valuable services to home care agencies and their clients. In order to begin or continue providing such services agencies must be assured of adequate coverage. Since dietary and nutrition services are not covered, as such, under Medicare, agencies should consult with fiscal intermediaries, carriers, and home care accountants on billing and cost-allocation methods.

Humans↗
PubMed1989

Quantitative autoradiographic characterization of L-[3H] glutamate binding sites in rat vestibular nuclei.

Quantitative autoradiography has been used to characterize L-[3H] glutamate binding sites and to describe their distribution in frozen sections of rat vestibular nuclei. Scatchard plots and Hill coefficients of glutamate binding suggest that glutamate interacts with a single population of sites having a KD of about 126 nM and a capacity of 2.5 pmol/mg of protein. Although the level of glutamate binding was not very high compared to the highest levels described for some other brain regions, it was nonetheless substantial. The sites were distributed unevenly in the four vestibular nuclei and their distribution correlated well with the projection areas of the vestibular nerve, which has been described as a glutamate-mediated pathway. The highest numbers of glutamate binding sites were observed in the medial vestibular nuclei. This technique provides a very sensitive assay for characterizing the pharmacological subtypes of glutamate binding in the vestibular nuclei and for analyzing changes in these sites during development or after deafferentation of the vestibular nuclei.

Animals↗