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D Vidal

Publications and source records attributed to D Vidal.

35 records · Page 2Linked to original sources
PubMed1989

[Programming VTIM physiologic pacemakers (evoked QT)].

Seventeen VTIM pacers were implanted in seventeen patients. Average follow up were 16.7 months. This paper concerns TX track and TX on modes only. Sensing window period and slope, which determine the rate response, must be programmed carefully. Potential competitive rhythms, severe ventricular arrhythmias or inadequate rate response to physical stress may potentially develop under inadequate programming. Consequently, it is advisable to program the sensing window 20-25 ms longer than the QTE max (at LRL) and the slope at 100% of the whole value. No complications were detected. Figures 1, 2 and 3 show examples of competitive rhythms without heart stimulation and unsensed beats by abnormally long programmed SW values. When properly shortened, this interval allows proper measurement of the Stim.-T and no competitive rhythm, during almost the same spontaneous rhythm. This system fulfills the major conditions for pacing the heart: rate adaptation to neurohormonal release, to physical stress and operative mode as a close-loop system during the recovery period.

Adaptation, Physiological↗
PubMed1988

Influence of metabolic and physical factors on production of diacetoxyscirpenol by Fusarium sambucinum Fuckel.

Fusarium sambucinum Fuckel 8099-1 was grown on Czapek-Dox peptone-supplemented medium at 15 degrees C for 14 days, and the cultures were investigated for diacetoxyscirpenol (DAS) production by liquid-liquid extraction and gas chromatography. The addition of 150 mg of sorbic acid, a tricarboxylic acid cycle inhibitor, per liter stimulated both fungal growth and DAS production. Among the beta-hydroxy-beta-methylglutaryl coenzyme A precursors tested, isovaleric acid completely inhibited fungal growth and DAS production, ethyl isovalerate did not support a significant increase in DAS production, and L-leucine partially inhibited DAS production, showing that L-leucine and isovaleric acid catabolisms do not induce trichothecene biosynthesis. Solid particles (cork powder) were necessary for DAS production in stationary cultures but did not influence DAS production in shaken cultures. Shaking strongly stimulated DAS production and fungal growth.

Acyl Coenzyme A↗
PubMed1987

Early inhibition of natural and interferon-activated killers in endometrial cancer patients treated with local radiotherapy.

The present study was aimed at comparing the effect of clinical staging and radiotherapy on natural killer (NK) and interferon-activated killer (IAK) cell activity in a group of endometrial cancer patients receiving a total dose of 5,000 to 8,000 rads. We report that when compared to age-matched women, a significantly higher number and percentage of patients show low NK and IAK cell activity. At diagnosis, diminished NK activity was seen in about 20% of the patients, while IAK activity was low in 49% of these patients. There was no correlation between these deficiencies and the grade or stage of the disease. In contrast, radiotherapy induced deleterious effects on both populations of NK and IAK cells. These deleterious effects were more pronounced in patients showing a low level of spontaneous NK activity. In an attempt to understand better the mechanism by which the presence of cancer itself and/or radiotherapy affects these activities, we studied in greater detail changes in peripheral blood T-cell numbers and subsets. Before radiotherapy, all lymphocyte counts were within the normal range. In contrast, after radiotherapy the absolute numbers of all T-cell subsets were significantly decreased in the majority of the patients tested, OKT4+ cells being the most radiosensitive and Leu 7+ cells the most radioresistant.

Female↗
PubMed1987

Production and characterization of monoclonal antibodies showing a different spectrum of reactivity to human breast tissue.

We have generated three hybridoma-producing monoclonal antibodies (MAs) that show a different spectrum of reactivity to human mammary tissues. Two of these antibodies, 1F10B4 and 1F10G2, recognize a cytoplasmic determinant highly expressed in most of the primary and metastatic breast carcinomas studied, and weakly (or not at all) in normal breast and nonbreast tissues. 3C6F9 detected a surface determinant common to both normal and neoplastic mammary epithelium. Five hundred hybridomas were obtained from the fusion of NS-1 myeloma cells with spleen cells of mice hyperimmunized with the well-characterized human breast carcinoma cell line BT-20. After the initial screenings and clonings, three monoclonal antibodies (1F10B4, 1F10G2, and 3C6F9) showing a restricted range of reactivity were selected for further investigation. These three antibodies recognized a panel of neoplastic mammary cell lines; however, the degree of reactivity could not be correlated to any of the various characteristics of these epithelial cell lines. Moreover, immunofluorescence analysis of acetone-fixed cryostat section showed that 1F10B4 and 1F10G2 recognize the vast majority of the 37 primary and metastatic breast cancers tested, binding strongly to 47% and 67% of them respectively. Only one of the primary carcinomas was not recognized by 1F10B4. On the other hand, these two MAs reacted weakly or not at all with normal breast and nonbreast tissues showing only few focal reactivities with the luminal pole of some ducts of the breast; very weak staining in renal tubular epithelial cells, in few keratinocytes and epithelial cells lining some sebaceous glands in the skin; and a moderate staining in biliary ducts of the liver. All mesenchymal structures including smooth and striated muscle tissues, lymph nodes, and connective tissue were negative. On the other hand, 3C6F9 recognized a more limited number of human mammary tumors and reacted with normal ductal epithelium in the breast and with nonbreast tissues. Because of their wide spectrum of reactivity with breast cancer cells and restricted recognition of normal mammary tissues, their cytoplasmic localization, and their heterogeneous distribution within a single neoplasm, 1F10B4 and 1F10G2 are now being used to characterize antigenic phenotypes of tumor-associated antigens in retrospective studies performed on conventional formalin-fixed, paraffin-embedded human mammary carcinomas.

Animals↗
PubMed1985

Rapid large-scale purification of plasmid DNA by medium or low pressure gel filtration. Application: construction of thermoamplifiable expression vectors.

This paper describes a new method of plasmid DNA purification which is fast and reliable enough for most purposes in recombinant DNA technology. The present method does not require the use of toxic chemicals such as phenol or ethidium bromide, costly ultracentrifugation procedures or other processes which can modify the supercoiled structure of the plasmids, such as adsorption on glass fiber. This method is based on the principle of gel filtration chromatography, at low pressure (1 bar) or medium pressure (between 5 and 10 bars), using Sephacryl S1000 or Superose 6B. It permits recovery of plasmids: in preparative quantities (from 300 micrograms to 4 mg), exempt from RNA, DNA and protein contamination, and suitable for various common genetic engineering procedures immediately after purification. To test the reliability of the technique as well as the degree of purification, the plasmids were used to construct thermoamplifiable vectors, carrying the lacUV5 promoter and the 5' end of the beta-galactosidase gene with a single EcoR1 site in each of the three possible translational phases. This set of vectors is designed for the expression of foreign genes as hybrid proteins in Escherichia coli.

Chromatography, Gel↗
PubMed1984

[Thyroid nodules. Diagnostic value of fine-needle biopsy. 159 surgical patients].

Between October 1980 and March 1983 we explored 269 patients who had one or several thyroid nodules with low or normal technetium 99 uptake. Each palpable nodule was aspirated 1 to 3 times, using a fine 21 G2 needle, and the aspirates were immediately spread on glass-plates and kept in alcohol-ether. After staining by the Harris- Shor method, all plates were examined by the same cytologist. Biopsies were unassessable in 50 patients (18%), mainly because they were entirely made up of red cells. Sixty patients did not undergo surgery. In the 159 patients operated upon, cytology was compared with histology which showed 139 benign and 20 malignant nodules. In 5 histologically benign nodules, cytology had shown nuclear abnormalities or enlarged cells suggestive of malignancy (false-positive results: 3.5%). Among 5 nodules diagnosed as benign at cytology, there were 2 papillary microcarcinomas , 2 to 4 mm in diameter, the course of which is little known, 1 well differentiated vesicular cancer extremely difficult to distinguish from vesicular adenoma, and 2 papillary cancers. Fine needle biopsy cytology is a harmless procedure, but it requires considerable experience on the part of cytologists. We consider that it should be performed in all cases of thyroid nodule, either to help in deciding whether or not to operate, or to guide the surgeon in deceding whether or not to operate, or to guide the surgeon in his operative strategy.

Biopsy, Needle↗
PubMed1984

[Effect of temperature on diacetoxyscirpenol production and on sporulation in a liquid culture of Fusarium sambucinum].

F. sambucinum grown for 14 days on peptone supplemented Czapek medium produced higher amount of diacetoxyscirpenol at + 15 degrees C than at + 25 degrees C or at temperature kept successively at + 15 degrees C (day) and + 5 degrees C (night). There was no correlation between the spores number and the toxin level, but toxin synthesis began only with sporification and then continued until the 14th day.

Fusarium↗
PubMed1983

[Experimental infection of mice by Salmonella typhi inoculated orally: influence of immunosuppressive therapy].

Various immunosuppressive treatments were used in order to induce a Salmonella typhi infection in mouse by oral route. Neither low protein diets nor administration of mucin, iron, streptomycin or silica could modify animal's sensitiveness, but, cyclophosphamide injections enhanced lethal effect of bacteria, while silica increased the number of bacteria in the blood and the spleen.

Administration, Oral↗
PubMedDate not supplied

Comparison of the efficacy and safety of two preseasonal regimens of glutaraldehyde modified, tyrosine-adsorbed parietaria pollen extract over a period of three years in monosensitive patients.

The purpose of this study was to evaluate the clinical efficacy over a period of three years (1988-90) of two preseasonal dosage regimens of a Parietaria allergoid (Bencard Tyrosine Parietaria) in patients who were only sensitive to this pollen. Fifty patients were included (14 men and 36 women, age: mean, 28 years; range, 14-47 years). Twenty five patients (group A) were treated each january with the basic course of Bencard Tyrosine Parietaria. This consisted of injecting subcutaneously 0.5 ml from each of three vials, with one week between each injection. A further injection using the vial with the highest dose was given one week later. Each january and february, twenty five patients (group B) were treated with the basic course of Bencard Tyrosine Parietaria, repeating the last dose five times, with one week between each injection. Immunotherapy with a tyrosine-adsorbed Parietaria judaica allergoid is an effective method for mitigating nasal (p < 0.0001), bronchial (p < 0.005), conjunctival (p < 0.001) and palatal itching symptoms (p < 0.0001) in patients who are sensitive to this pollen. Sensitivity to Parietaria pollen, as verified by skin test and nasal challenge, decreased during immunotherapy (p < 0.001). Histamine release by peripheral blood basophils decreased during the course of the study, falling from 43.5 ng/ml to 12.3 ng/ml in group A and from 42.9 ng/ml to 10.0 ng/ml in group B; during the second and third years, IgG levels were increased one and four months after starting treatment with the extract, while this was not the case after ten months; IgE levels were also increased. Finally, overall tolerance to this immunotherapy product was good in almost all patients.

Adolescent↗