Search PubMed⌕ Search

Biomedical subjects

P Perrin

Publications and source records attributed to P Perrin.

At least 109 records · Page 6Linked to original sources
PubMed1993

Clinical response to transurethral microwave thermotherapy is thermal dose dependent.

Transurethral microwave thermotherapy of the prostate was used to treat men with symptomatic benign prostatic hypertrophy. Three treatment protocols delivering increasing thermal doses (Prostasoft T-A > Prostasoft II > Prostasoft I) were evaluated. The results show a dose-dependent response. Histological changes induced by microwave heating were dependent on the temperature achieved in the tissue. Thermocoagulation is obtained above 45 degrees C and thermoablation above 60 degrees C. Using Prostasoft II in a long-term follow-up study, the Madsen symptom score decreased by 66% and peak flow rates increased by 41% over a period of more than 18 months. Using Prostasoft T-A (thermoablation) in 28 patients, a cavity was obtained inside the prostate without major complication. The symptoms and obstruction caused by benign prostatic hypertrophy can be treated by transurethral thermotherapy in a single, anesthesia-free 1-hour session on an ambulatory basis.

Follow-Up Studies↗
PubMed1993

Thermoregulation during transurethral microwave thermotherapy: experimental and clinical fundamentals.

Transurethral microwave thermotherapy of 340 patients treated at our center for benign prostatic hypertrophy shows the importance of the role played by two thermoregulation processes during the procedure. The first one is artificial and automatically driven by the machine (the power output and cooling rate are adjusted to the urethral and rectal temperature safety thresholds). The second one is natural thermoregulation; the latter is species specific, organ specific, zone specific and even cell specific. Thermoregulation variability is linked to the geometry of the gland, vessel distribution, histology and tissue conductivity. This variability has been demonstrated by interstitial thermometry and histological study. Interstitial thermometry was performed during treatment in 30 dogs and 35 patients; a histological study of prostate specimens was performed 1-12 weeks after treatment in 30 dogs and 15 patients. The human prostate is more resistant to heat than the dog prostate of a comparable volume and treated with the same thermal dose. The prostate of a young patient requires a higher thermal dose than that of an old patient with the same prostate volume in order to achieve a comparable intraprostatic temperature, probably due to a more viable blood supply. The transition zone is more sensitive to heat than the peripheral zone, as demonstrated by temperatures recorded at the same distance from the antenna of up to 60 versus 42 degrees C, respectively. Acinar cells seem to be more resistant to heat than smooth muscle cells when exposed to the same temperature level, as demonstrated by microscopic examination at the periphery of the treated area.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

[Treatment with butyrate/IL-2 combination in peritoneal carcinomatosis of colonic origin].

Two therapeutic assays associating sodium butyrate (NaB) and interleukin-2 (IL-2) were applied on rats after intraperitoneal (i.p.) injection of colon carcinoma cells. The first assay began at day 1 after cell injection, and the second one at day 10 after injection, i.e. when carcinomatosis was established. IL-2 was given i.p. three times per day and NaB one time per day, for five and seven days respectively. The survival median of IL-2 treated rats significantly increased versus those of untreated ones, and was much higher with NaB in supplement. Moreover, using this associative treatment, we observed some cases of complete curacy, even in rats bearing established carcinomatosis.

Animals↗
PubMed1992

Involvement of histo-blood-group antigens in the susceptibility of colon carcinoma cells to natural killer-mediated cytotoxicity.

The susceptibility to natural-killer-cell lysis and expression of histo-blood-group antigens of 2 clones from a rat colon adenocarcinoma, of variants derived from them and of 17 human colon carcinoma cell lines were assessed in an attempt to determine if the major glycosidic tissue antigens of epithelial cells could influence the NK susceptibility of tumor target cells of epithelial origin. The rat REGb clone, which is relatively NK-sensitive, expressed higher levels of precursor structures T and Tn and lower levels of H antigenic determinants than the PROb clone, which displays higher resistance to NK-cell lysis. Cell variants were obtained from these 2 clones; it appeared that whether the cell variants were selected on the basis of expression of a blood-group antigenic determinant or on the basis of altered susceptibility to NK-cell lysis, there was a link between increased resistance and higher expression of cell-surface A and H histo-blood-group antigens, or conversely, between increased sensitivity and higher expression of precursor structures. Similar conclusions were obtained upon study of the human cell lines, since a significant correlation was found between the level of expression of T or Tn antigens and sensitivity to NK-cell lysis. A significant relationship was found between the expression of Lewis antigens and increased resistance to NK-cell-mediated cytotoxicity.

ABO Blood-Group System↗
PubMed1992

Snoring in French preschool children.

The prevalence of habitual snoring and its associations with respiratory symptoms, personal and familial risk factors, ear, nose, and throat (ENT) abnormalities, and its influence on ventilatory function were studied in a sample of 190 children aged 5 to 6 years from nine kindergartens in Nancy (northeastern France). Nineteen (10%; 95% CI 5.7-14.3%) of the children were habitual snorers; the prevalence was the same in boys and girls. In univariate analysis habitual snoring was significantly associated with a personal history of exercise-induced bronchospasm [relative risk (RR) 4.50]; a history of adenotonsillectomy (RR, 2.56); a personal history of allergy (RR, 2.83); a sibling history of atopy (RR, 2.39); and doctor-assessed tonsillar hypertrophy (RR, 2.51). These factors were entered into a logistic regression model that retained as independent determinants exercise-induced asthma, personal history of allergy, sibling history of allergy, and tonsillar hypertrophy. The height-adjusted peak expiratory flow rate was slightly, non-significantly lower in habitual snorers as compared to non-snorers (2.01 +/- 0.32 vs 2.10 +/- 0.38 L/s/m2). Due to the limited numbers in the sample, the increased risk for paternal (RR, 1.8) and maternal (RR, 1.6) smoking at home remained nonsignificant.

Child↗
PubMed1992

Modulation of extracellular matrix glycoproteins production by in vitro interacting conditions between rat colonic fibroblasts and tumoral cells.

Mixed cultures of fibroblasts with rat colon carcinoma cell lines were used to investigate the production of extracellular matrix glycoproteins. Tumoral cells were shown to influence their production in different ways depending on the cell clone (PROb cells which in vivo produce progressive tumors and REGb cells which produce regressive ones) but also on the relative proportions of stromal and tumoral cells. When fibroblasts were predominant, the REGb cells containing mixture produced higher levels of all protein studied as compared with the PROb cells containing system. When the situation was reversed in favor of tumoral cells, REGb cells containing cocultures still produced more fibronectin, laminin and undulin, but the difference with PROb ones was reduced. On the opposite, cocultures enriched with PROb cells made more entactin and SPARC and approximately equal amounts of tenascin.

Animals↗
PubMed1992

A modified rapid enzyme immunoassay for the detection of rabies and rabies-related viruses: RREID-lyssa.

This paper presents a modification of the previously described Rapid Rabies Enzyme Immuno-Diagnosis test (RREID) by using biotinylated antibodies, streptavidin conjugate and a mixture of monospecific polyclonal antibodies against several lyssaviruses. In the modified technique (RREID-lyssa), microplates were sensitized with a mixture of purified antibodies against ribonucleoprotein (RNP) from Pasteur virus (Lyssavirus serotype 1), European Bat Lyssavirus (EBL, unclassified) and Mokola virus (Lyssavirus serotype 3). Bound RNP was detected by the same antibodies labelled with biotin and peroxidase-strepavidin conjugate. These techniques were used for the detection of RNP of different Lyssavirus serotypes (rabies and rabies-related viruses). For lyssavirus specimens of serotype 1, the threshold of detection of RREID and RREID-lyssa were similar. However, a smaller amount of labelled antibodies was needed when biotinylated antibodies were used. For specimens infected by rabies-related strains (serotypes 2, 3, 4 and EBL), the threshold of detection of the RREID-lyssa was between two and 512 times lower than with the RREID. The sensitivity and the specificity of the RREID-lyssa for rabies virus (serotype 1) when tested on a small field trial (53 specimens) were found to be identical to the RREID. Consequently, RREID-lyssa can be a useful tool for diagnostic laboratories that receive specimens infected by rabies-related viruses.

Animals↗
PubMed1992

[Progression after radical prostatectomy of cancer of the prostate: prognostic criteria and the role of PSA in monitoring].

Progression after radical prostatectomy, evaluated by a rise in plasma PSA and/or the appearance of a pelvic nodule positive on biopsy and/or the presence of bone metastases confirmed by bone scan, was studied in a series of patients with prostatic cancer with a follow-up of between 6 months and 5 years. The progression-free survival rate was 86% at 1 year and 60% at 5 years. A progression-free survival rate and the relative risk of progression were established on the basis of the morphological characteristics (anatomical stage, tumour volume, seminal vesicle invasion, condition of the prostatic capsule and lymph nodes, positive resection margins at the apex) and histological features (Gleason's score) of the cancer, allowing determination of the influence of prognostic criteria on the outcome. The positive resection margins at the apex were due to preservation of the nervi erigentes. The preservation of the neurovascular pedicles may not be justified in the case of a tumour confined to the prostatic apex.

Adenocarcinoma↗
PubMed1992

[Spa treatment in pediatric pneumo-allergology and ENT].

Each year in France, 42,000 children receive spa therapy, which is covered by the national health care insurance system. In over three cases out of four, the treatment is ordered by the child's physician for respiratory tract disease which fails to respond adequately to conventional therapy. Asthma, recurrent bronchitis, and spasmodic cough are the main indications in pneumo-allergology; seromucous otitis media, naso-sinusitis and refractory pharyngitis are the most common pediatric ENT diseases treated in spa centers. The two main types of mineral water used are sulfur-rich waters in patients with prominent infection and chloride and bicarbonate-rich waters when allergy is the main problem. Experimental studies point to the fact that these waters have immunomodulating effects. However, other therapeutic interventions in spa centers, including rehabilitation and health education, also play a role. Evaluations of spa therapy for respiratory tract diseases carried out by government agencies have demonstrated decreases in school absenteeism and above all in the use of drugs in treated patients. The future of pediatric spa therapy will likely depend on the development of preventive interventions in spa centers.

Asthma↗
PubMed1992

[Vestibular studies: current status, prospects].

Equilibrium is based on gaze stabilization. Clinical examinations currently test, individually the three components involved in equilibrium: vestibular, visual and proprioception. New investigations are being developed to test equilibrium dynamic conditions. After briefly reviewing vestibular physiology, under the authors discuss the various tests of vestibular function and equilibrium.

Eye Movements↗
PubMed1991

[Circulating prostate cancer specific antigens in benign hypertrophy and localized cancer of the prostate].

In benign hypertrophy of the prostate (88 patients) there is a good correlation between the circulating specific prostate antigen (SPA) and the size of the prostate or of the adenoma. This correlation disappears with an adenocarcinoma where tumor volume increases (46 patients). Used as a screening test for cancer, serum levels of SPA, with a threshold value of 2.5 ng/ml, has a 91 per cent sensitivity and a 37 per cent specificity. At 15 ng/ml the sensitivity is 50 per cent and the specificity is 85 per cent. Alone, the SPA level is a poor diagnostic tool: using the low threshold (2.5 ng/ml) leads to needle biopsy in most all benign hypertrophies; with the high threshold (15-23 ng/ml), 50 per cent of the localized cancers go undetected. However, for a level greater than 15 ng/ml, SPA is an argument strongly suggesting prostate adenocarcinoma. The capacity of benign hypertrophy of the prostate to "secrete" SPA is 5 times greater than the normal peripheral prostate; the capacity of cancer is 20 times greater than that of the adenoma. Individual variability in serum levels of SPA, expressed per cm3 of prostate tissue is too great to give a precise interpretation as a function of volume.

Adenocarcinoma↗
PubMed1991

Rabies-specific production of interleukin-2 by peripheral blood lymphocytes from human rabies vaccinees.

Cell-mediated immunity induced by rabies vaccination was studied in humans by the determination of specific interleukin-2 (IL-2) production in a large number of donors (postexposure immunized patients and pre-exposure immunized laboratory workers). Peripheral blood lymphocytes (PBL) from 35 donors were tested for IL-2 production after in vitro stimulation by different rabies and rabies-related viruses. IL-2 responses were compared to antibody recognition of these different virus serotypes by sera from the same individuals. IL-2 was produced by PBL from more than 85% of donors after stimulation with inactivated and purified rabies viruses (IPRV) prepared from either Pittman Moore (PM) or Pasteur Virus (PV) strains. IL-2 was also produced by 65 and 45% of donor PBL stimulated with IPRV from the European Bat Lyssavirus (EBL) and Mokola (Mok) rabies-related virus strains respectively. No correlation was found between the production of IL-2 by PBL and the levels of virus neutralizing antibody (VNAb). Moreover, 50, 25 and 35% of donors produced IL-2 after stimulation of their PBL with ribonucleoprotein (RNP) from PV-, EBL- and Mok-viruses, respectively. These results obtained with a large number of human rabies vaccinees and using an assay specific to T-cell activation confirm the significant cross-reactivity of T-cell responses directed against rabies and rabies-related viruses. This study shows that IL-2 production could be used for the study of cell-mediated immunity and T-cell memory induced in humans by rabies vaccination.

Adult↗
PubMed1991

Appraisal of rabies vaccine potency by determination of in vitro, specific interleukin-2 production.

The potency of different rabies vaccines was measured via cell mediated immunity (CMI) assessed by the production of interleukin-2 (IL-2) by CD4+CD8- lymphocytes. IL-2 production by splenocytes from mice immunized with various vaccines was measured following in vitro stimulation with antigens from different rabies and rabies-related strains. IL-2 production was specific, reproducible and correlated with the vaccine protective activity as determined by the pre-exposure NIH test. Our results suggest that measurement of IL-2 production could be used for the appraisal of rabies vaccine potency.

Animals↗