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Biomedical subjects

F Guillemin

Publications and source records attributed to F Guillemin.

At least 91 records · Page 5Linked to original sources

[The mesorectum: improvement and anatomy of a semantic error].

AIMS: The cancer of the rectum touches 10,000 patients per year in France. Its treatment is mainly surgical. 50% of the treated patients will die of their cancer, either by loco-regional recurrence, or by metastatic disease. The rates of local recurrence vary from 10 to 40%. Heald is first who brought back recurrence rates lower than 4%, results obtained by the only surgical treatment. This treatment included the total exeresis of cellulo-fatty tissue surrounding the rectum, tissue which was baptized mesorectum. The aims of this work is to define and describe this space, and to discuss its Christian name. MATERIAL AND METHODS: The anatomical study carries on the dissection of 2 frozen pelvis of fresh man, one cut transversely on the level of L4, the other half-compartment sagittaly, then defrosted for the dissection. RESULTS: The mesorectum is defined and its various structures, fascia, vessels and nerves, are detailed. CONCLUSION: The mesorectum is an anatomical and surgical structure individualisable. Its recognition and its importance were born from the understanding of the fascia and the rectal anatomy. Its exeresis decreases the rate of the local recurrence (18). The technique of exeresis of the mesorectum must be validated, standardized, in order to be reproducible in the treatment of the cancer of the rectum.

Female↗

Bias and precision in visual analogue scales: a randomized controlled trial.

Various types of visual analogue scales (VAS) are used in epidemiologic and clinical research. This paper reports on a randomized controlled trial to investigate the effects of variations in the orientation and type of scale on bias and precision in cross-sectional and longitudinal analyses. This trial was included in the pilot study of the SU.VI.MAX (supplementation by antioxidant vitamins and minerals) prevention trial in France in 1994. Six types of VAS (simple, middle-marked, graphic rating, graduated, graduated-numbered, and numerical rating) and two orientations (horizontal and vertical) were used to measure three symptoms of ear, nose, and throat infection at 2-month intervals in 870 subjects. Differences between scales were analyzed by comparing variances (Levene's test) and means (variance-covariance analysis for repeated measures). Scale characteristics were shown to influence the proportion of zero and low values (i.e., there was a floor effect), but not mean scores. The precision of measurements varied cross-sectionally according to the type of scale, but no differences were observed in the precision of measurement of change over time. In conclusion, the characteristics of VAS seem to be important in cross-sectional studies, particularly when symptoms of low or high intensity are being measured. Researchers should try to reach a consensus on what type of VAS to use if studies are to be compared.

Adult↗

Meta-tetra(hydroxyphenyl)chlorin-sensitized photodynamic damage of cultured tumor and normal cells in the presence of high concentrations of alpha-tocopherol.

Alpha-tocopherol at low concentrations protects biosubstrates from oxidative damage, while at high concentrations it may become toxic. Certain lines of tumor cells are reported to contain higher levels of vitamin E than normal cells. In our study alpha-tocopherol was successfully incorporated by cultured HT29 adenocarcinoma cells, but not by MRC-5 normal fibroblasts. At high concentrations (0.3-1 mM) alpha-tocopherol enhanced meta-tetra(hydroxyphenyl)chlorin (mTHPC)-sensitized photoinactivation of HT29 cells (415 nm), but not that of normal fibroblasts. At none of the concentrations used (0.001-1 mM) did alpha-tocopherol protect cells from photokilling, indicating that lipid peroxidation is of minor importance in mTHPC photoactivity. Our findings encourage the in vivo testing of phenolic antioxidants for selective enhancement of PDT-damage in tumors.

Adenocarcinoma↗

Quality of life in ankylosing spondylitis: validation of the ankylosing spondylitis Arthritis Impact Measurement Scales 2, a modified Arthritis Impact Measurement Scales Questionnaire.

OBJECTIVE: To develop a questionnaire measuring quality of life in ankylosing spondylitis (AS). METHODS: A focus group technique contributed to the generation of an AS-specific questionnaire using the Arthritis Impact Measurement Scales 2 (AIMS2) (12 dimensions), supplemented with items from the Health Assessment Questionnaire for the Spondylar-thropathies, as well as original new items. Patients from a self-help group provided data to assess the validity (n = 146) and reproducibility (n = 43) of the AS-AIMS2. RESULTS: The focus group generated a thirteenth dimension including 6 items labeled "spine mobility." Principal component analyses on AS-AIMS2 showed satisfactory dimensionality (74.1% of variance explained), high internal consistency (Cronbach's alpha = 0.78-0.91), significant convergent validity of the new dimension with spine pain and mobility, and good reproducibility in the 13 dimensions and 5 components (intraclass correlation coefficient = 0.7-0.9). The scores in each component of the AS-AIMS2 showed a marked deterioration of quality of life in these young patients. CONCLUSIONS: The disease-specific AS-AIMS2 questionnaire should help improve care management in AS.

Activities of Daily Living↗

Subcellular localization of meta-tetra (hydroxyphenyl) chlorin in human tumor cells subjected to photodynamic treatment.

Subcellular localization of meta-tetra (hydroxyphenyl) chlorin (mTHPC) in HT29 human colon adenocarcinoma cells has been studied by means of fluorescence microscopy. The observed diffuse intracellular distribution of mTHPC fluorescence outside the nucleus indicates general staining of cellular organelles. No changes in dye fluorescence pattern are evident during and immediately after cell illumination. Alternatively, the changes in mTHPC fluorescence pattern are observed upon subsequent cell incubation, and are characterized by the appearance of distinct bright fluorescence zones. Reaching a maximum 1 h after illumination, modifications of the fluorescence pattern then gradually disappear in parallel with the formation of plasma membrane blebs, suggesting that cell necrotic lysis is taking place. Photosensitized damage to mitochondria and the Golgi apparatus has been studied using fluorescent probes 1 h after irradiation, the stage of extensive cytoplasm vacuolization, and reveal alterations of these organelles. Changes in the mTHPC fluorescence pattern and mTHPC photocytotoxicity, as measured by the MTT test 24 h after illumination, are inhibited by sodium azide, a singlet oxygen quencher.

Fluorescent Dyes↗

Foscan (mTHPC) photosensitized macrophage activation: enhancement of phagocytosis, nitric oxide release and tumour necrosis factor-alpha-mediated cytolytic activity.

Photodynamic activation of macrophage-like cells contributes to an effective outcome of photodynamic therapy (PDT) treatment. The possibility for an enhancement of macrophage activity by photosensitization with meta-tetra(hydroxyphenyl)chlorin (mTHPC) (1 microg ml(-1)) was studied in U937, monocyte cell line differentiated into macrophages (U937) cells). Phagocytic activity of U937phi cells was evaluated by flow-cytometry monitoring of ingestion of fluorescein-labelled Escherichia coli particles. Increase in irradiation fluence up to 3.45 mJ cm(-2) (corresponding irradiation time 15 s) resulted in significant increase in fluorescence signal (145%), while at higher light fluences the signal lowered down to the untreated control values. A light energy-dependent production of tumour necrosis factor-alpha (TNF-alpha) by photosensitized macrophages was further demonstrated using the L929 assay. The maximum TNF-alpha mediated cytolysis was observed at 28 mJ cm(-2) and was 1.7-fold greater than that in control. In addition, we demonstrated a fluence-dependent increase in nitric oxide (NO) production by mTHPC-photosensitized macrophages. NO release increased gradually and reached a plateau after irradiation fluence of 6.9 mJ cm(-2). Cytotoxicity measurements indicated that the observed manifestations of mTHPC-photosensitized macrophage activation took place under the sublethal light doses. The relevance of the present findings to clinical mTHPC-PDT is discussed.

Animals↗

Multivariate analysis of predictors of cerebral vasospasm occurrence after aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The role of type of treatment on cerebral vasospasm occurrence after aneurysmal subarachnoid hemorrhage (SAH) has not been studied. Through multivariate analysis we determined the independent prognostic factors of the occurrence of symptomatic vasospasm following aneurysmal SAH in a study cohort of 244 patients undergoing either surgical or endovascular treatment. The prognostic factors of sequelae after aneurysmal SAH were studied as well. METHODS: Symptomatic vasospasm was defined as the association of deterioration in a patient's neurological condition between 3 and 14 days after SAH with no other explanation and an increase in mean transcranial Doppler velocities of >120 cm/s. The prognostic factors were registered on admission and during the intensive care stay. RESULTS: Symptomatic vasospasm occurred in 22.2% surgical patients compared with 17.2% endovascular treatment patients (P=0.37). Multivariate analysis revealed that the probability of occurrence of symptomatic vasospasm decreased with age >50 years (relative risk [RR], 0.47 [0.25 to 0.88]) and severe World Federation of Neurological Surgeons (WFNS) grade measured on admission (RR, 0.43 [0.20 to 0.90]) and increased with hyperglycemia occurring during the intensive care stay (RR, 1.94 [1.04 to 3.63]). No difference in risk of symptomatic vasospasm could be identified between surgical and endovascular treatment. Symptomatic vasospasm (OR, 4.73 [CI, 1. 77 to 12.6]) as well as WFNS grade of >2 (OR, 8.95 [3.46 to 23.2]), treatment complications (OR, 8.39 [3.16 to 22.3]), and secondary brain insults were associated with an increased risk of 6-month sequelae. CONCLUSIONS: Age <50 years, good neurological grade, and hyperglycemia were all associated with an increased risk of cerebral vasospasm whereas treatment was not. This provides a basis for future clinical prospective randomized trials comparing both treatments.

Adult↗

Induction of superficial bladder tumors in the female Fischer 344 rats with AY-27 tumor cells for the study of diffusion and localization of hemoglobin derived components (hematoporphyrin derivative) in view of photochemotherapy.

Photochemotherapy (PCT) consists in administration of a photosensitizer and subsequent irradiation of the tumor with visible light. Routinely, the photosensitizer is given intravenously (i.v.), but the major drawback of this procedure is the resulting skin photosensitivity. The goal of our study is to examine whether intravesical (i.b.) instillation of the photosensitizer for PDT of bladder cancer might be feasible in order to target the tumors and to avoid the photosensitization phenomenon. After first studying the biodistribution of hematoporphyrin derivative (HpD) in vivo in the rat bladder, two and four hours after intravesical administration, by fluorescence microscopy, we compared two different methods for the induction of superficial bladder tumors in rats with AY-27 tumor cell line in order to perform the same study on bladder tumors. The best results for the penetration depth of HpD in the normal bladder wall were obtained two hours after the bladder instillation where the photosensitizer was detected only in the bladder surface (urothelium and small part of the chorion). That's why we must choose the most appropriate bladder tumor model in order to obtain superficial bladder tumors that mimic the clinical behavior of superficial bladder cancer in man. Both techniques used in this study gave a high tumor take rate in a short time (> 90%). But we really obtained superficial bladder tumors directly attached to the bladder surface with one of the two methods of tumor induction consisting in the abrasion of the bladder surface prior to the administration of the tumoral cells in the bladder cavity.

Animals↗

Determination of endogenous porphyrins and the maximal HpD tumor/normal skin ratio in SKH-1 hairless mice by light induced fluorescence spectroscopy.

The treatment of skin tumors is an application of photochemotherapy (PCT) which involves an initial administration of a photosensitizer (PS) followed by irradiation with a light beam that causes the PS to produce cytotoxic oxygen species within the tumors. As the PS is also present in normal skin, it is necessary to know how it is distributed between the two tissues. In this study, we have used SKH-1 hairless mice bearing papillomas or carcinomas chemically induced. The biodistribution of hematoporphyrin derivative (HpD) and the tissue autofluorescence measurements were studied by light induced fluorescence spectroscopy. The tumor and normal autofluorescence spectra measured on control mice with papillomas or carcinomas had a very similar shape. However, the principal endogenous porphyrin peak at about 630 nm showed a fluorescence signal amplitude 2 (for papilloma) and 1.5 (for carcinoma)-fold higher than the one found for the normal skin. Moreover, the fluorescence intensity of carcinoma spectrum is 1.4-fold lower than the one of papilloma spectrum at 630 nm. The tissue autofluorescence can be used to distinguish tumor from normal skin and benign from malignant tumor. This difference in fluorescence intensity at 630 nm was directly related to the concentration of endogenous porphyrins in the tumor. Fluorescence intensity ratios between tumor and normal skin were measured 4, 8, 24, 48, 72 and 96 hours after intraperitoneal injection of HpD (5 mg/kg body weight). The best tumor/normal skin ratio was 6.2 for HpD and the time required to reach this ratio was 48 h. HpD showed a moderate selectivity since the ratio was higher than 1 during the four first days. Photodynamic therapy with the same dose of HpD used in this biodistribution study must also be carried out to verify that the maximal tumor/skin ratio corresponds to the maximal efficiency of HpD.

Animals↗

Histamine content does not influence the tolerance of wine in normal subjects.

Histamine has been incriminated as having a responsibility for intolerance reaction to wines. We have made a study by double blind oral provocation test to find the effect of ingestion of a histamine-rich (22.8 mg.l-1) and a histamine free wine in eight healthy subjects. Blood samples were taken at 0, 10, 30 and 45 minutes after ingestion of the wine for measurement of plasma histamine and methylhistamine. Urines were collected 5 hours before and 5 hours after ingestion for measurement of urinary methylhistamine. No subject presented a reaction of intolerance after ingestion of wine rich or poor in histamine. No change in plasma histamine and plasma and urinary methylhistamine was seen. This study shows that the amount of histamine in wine has no clinical or biological effect in healthy subjects, and this emphasized the efficiency in man of the systems for degradation of histamine that is absorbed by the alimentary tract.

Adult↗

[Endocervical glial implant].

We report a new case of glial tissue in uterine cervix found in a 63 year-old woman with an abortion 30 years ago. The lesion, measuring 0.5 cm in diameter, showed a typical feature of mature glial tissue immunoreactive for the glial fibrillary acid protein. Hypothesis concerning its histogenesis (fetal graft, tumor, metaplasia) are discussed. Fetal implantation is likely as in the majority of published cases.

Abortion, Therapeutic↗

Photodynamic properties of meta-tetra(hydroxyphenyl)chlorin in human tumor cells.

The photodynamic properties of a second-generation photodynamic sensitizer, meta-tetra(hydroxyphenyl)chlorin (mTHPC) were studied by dye-sensitized photoinactivation (650 nm) of HT29 human adenocarcinoma cells in culture. The photocytotoxicity of mTHPC in vitro depended on the presence of molecular oxygen. A strong inhibition of the photocytotoxicity of mTHPC was observed upon addition of sodium azide, a known singlet oxygen quencher. Photocytotoxicity was not inhibited by scavengers of superoxide anion radical, hydrogen peroxide and hydroxyl radicals. We suggest that mTHPC photosensitizes cell killing predominantly by type II, singlet oxygen-mediated photodynamic reactions. Illumination of cells preloaded with mTHPC induced peroxidation of membrane lipids. Inhibition of photoperoxidation by alpha-tocopherol (0.1 mM) present during illumination did not result in any decrease in toxicity, suggesting that reactions of lipid peroxidation play only a minor role in the overall photocytotoxic effect of mTHPC.

Cell Survival↗

Compliance to drug treatment of patients with rheumatoid arthritis: a 3 year longitudinal study.

OBJECTIVE: Patient compliance is considered necessary for the success of drug treatment in chronic diseases. We document compliance with drug treatment and the factors affecting it in a cohort of patients with rheumatoid arthritis (RA). METHODS: A prospective cohort study of 556 patients with RA followed for 3 years in 4 counties: Oslo, Norway; Groningen, The Netherlands; and Nancy and Reims, France. Compliance to treatment was assessed annually by interview in terms of adherence to the dose and timing of the prescribed drug regimen. RESULTS: Of the 556 subjects, 429 (77.2%) were taking medication for RA throughout the observation period. Consistent behavior was recorded in 59.5% of cases: 35.7% were consistently compliant, and 23.8% consistently noncompliant. Factors significantly associated with good compliance were older age (p = 0.00), female sex (p = 0.03), decreased disability (p = 0.04), very satisfactory contacts with health care professionals (p = 0.03), and more personal knowledge about the disease and its treatment (p = 0.03). CONCLUSION: This longitudinal study identified compliance behavior as consistent over time in 60% of patients, determined by quality of contact with professionals and the amount of patient information available.

Age Factors↗

Prevalence of rheumatoid arthritis and spondyloarthropathy in Brittany, France. Société de Rhumatologie de l'Ouest.

OBJECTIVE: To document the prevalence of rheumatoid arthritis (RA) and spondyloarthropathy (SpA) in Brittany, France. METHODS: (1) Members of rheumatism self-help groups screened cases using questionnaires. (2) Rheumatologists in our unit contacted persons who had possible inflammatory rheumatic diseases and persons who refused the first interview. (3) When diagnosis remained unknown or discordant with the questionnaire, the general practitioner or the rheumatologist of these patients was interviewed. (4) Patients without diagnosis and who had not had a rheumatological examination were examined without charge by a rheumatologist. RESULTS: An overall prevalence rate of 0.62% (0.33-0.91) and 0.47% (0.22-0.72) was found for RA and for SpA, respectively. The prevalence of RA and SpA was 0.86 (0.39-1.33) and 0.53 (0.16-0.9) in women and 0.32 (0.01-0.63) and 0.41 (0.05-0.77) in men. The minimum prevalence of RA and SpA calculated on the estimated initial group (3189 persons) was 0.53 (0.28-0.78) and 0.41 (0.18-0.63), respectively. CONCLUSION: Our telephone survey revealed that the prevalences of RA and SpA are nearly similar among our population and that SpA is as common in women as in men.

Adolescent↗