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R Perrin

Publications and source records attributed to R Perrin.

33 records · Page 2Linked to original sources
PubMed1990

Blood activity of Cu/Zn superoxide dismutase, glutathione peroxidase and catalase in Alzheimer's disease: a case-control study.

Cu/Zn superoxide dismutase (Cu/Zn SOD), glutathione peroxidase (GPx) and catalase, which are the three main enzymes involved in cellular protection against damage due to oxygen-derived free radicals have been assayed in plasma and erythrocytes obtained from subjects with dementia of the Alzheimer type (DAT) and from controls. Blood samples were obtained from 25 patients with DAT and from age-matched subjects without diagnoses of neurological disease (non-DAT), as well as from younger individuals (reference group). Using appropriate statistical procedures, the three enzyme activities measured in blood of the elderly were decreased if compared to the younger reference group. Moreover, a significant increase in erythrocyte Cu/Zn SOD and catalase activities of DAT patients was observed compared to the non-DAT group. These results are discussed taking the free radical theory of aging into consideration.

Aged↗
PubMed1989

Preoperative embolization in the treatment of osseous metastases from renal cell carcinoma.

Metastatic lesions due to renal cell carcinoma are frequently hypervascular. This study reports the results of preoperative embolization of skeletal metastases from hypernephroma. Reported for the first time in the English literature is the use of this technique for preoperative devascularization of metastatic lesions to the spine in eight patients. Effective devascularization was achieved in all peripheral lesions. Blood loss for peripheral lesions averaged 940 cc and compared favorably to 20 nonembolized cases, in whom average blood loss was 1975 cc. Spinal embolization requires careful identification and preservation of any segmental arteries that supply the anterior spinal artery. Effective spinal devascularization was achieved in six of eight patients. In two patients significant bleeding occurred as a result of incomplete embolization. This series supports the growing evidence for the efficacy and safety of selective arterial embolization in the preoperative control of hemostasis in patients with metastatic hypernephroma. Embolization of spinal metastases, although technically demanding, has been effective in devascularizing these lesions without serious neurologic complications.

Bone Neoplasms↗
PubMed1988

Binding of C3 and C3dg to the CR2 complement receptor induces growth of an Epstein-Barr virus-positive human B cell line.

The effect of ligand interactions with the C3d/C3dg complement receptor (CR2) on proliferation of human B lymphoblastoid cells was investigated by using cell cultures performed at low density (1 to 1.5 x 10(3) cells/ml) in a serum-free defined medium to which only transferrin had been added. This medium does not allow proliferation of Raji cells which die within 48 hr with formation of polykaryons. Addition of purified human C3 to the cultures resulted in a dose-dependent proliferation of the cells. A steady growth of Raji cells with a doubling time of 36 hr was observed in cultures containing 10 micrograms/ml of C3. A growth rate similar to that observed in the presence of native C3 was found in the presence of equimolar concentrations of purified C3dg but not of C3c. F(ab')2 anti-C3d but not F(ab')2 anti-C3c antibodies inhibited the mitogenic effect of C3. Preincubation of Raji cells with monoclonal antibody OKB7 which directly inhibits the binding of C3dg to CR2, totally suppressed C3-induced growth of the cells. C3 did not enhance growth of the T lymphoma-derived cell line JM and monocytic cell line U937 which do not express CR2. These results provide direct evidence that the interaction between CR2 and C3 fragments stimulates proliferation of human cells of the B lineage. Because CR2 also acts as a receptor for Epstein-Barr virus on B cells, our results may pertain to the B cell mitogenic properties of the virus.

B-Lymphocytes↗
PubMed1987

[Version by internal maneuvers: alternative to cesarean section under precarious conditions. The experience of the University Clinic of Gynecology and Obstetrics].

Obstetrics practised in African University Hospitals is beset with specific constraints. The emergency admission of a woman whose fetus is dead or severely compromised, after an extended labor and an obvious ovular infection, leads to fear an hysterotomy as well as an hysterectomy. The authors specify, under their work conditions, the indications of internal version maneuvers, from 50 cases collected in one year. The fetal prognosis is not taken into account since it concerns dead or very threatened children. As for the maternal prognosis, it is excellent since the average stay is of 48 hours and no severe infection developed, which is not the case for caesarean sections performed under the same circumstances. If a maternal death must be deplored, it concerned a placenta praevia in a distressing conjunction of circumstances since the blood bank was out of blood.

Adolescent↗
PubMed1987

[Epidemiologic approach to intrauterine growth retardation in the People's Republic of Benin].

Intra-uterine growth delay is always difficult to define since it is calculated in percentile of a newborn population and requires the creation of stature norms in the population studied. This study, from the maternity hospital in Cotonou, seems in favor of constitutional factors at the origin of fetal hypotrophism. The statistical analysis of the population shows, as a matter of fact, that the small size of the mother and a past history of repeated abortions are the only factors appearing significantly linked to hypotrophism.

Abortion, Spontaneous↗
PubMed1983

Intramedullary spinal cord metastases from small cell carcinoma of the lung.

Four patients with intramedullary spinal cord metastases from small cell carcinoma of the lung (SCCL) are described, with emphasis on clinical presentation and treatment. All patients developed the Brown-Séquard syndrome due to intramedullary tumor in the cervical spinal cord, three within 2 mo after combined modality treatment using chemotherapy and radiotherapy. One patient presented with a Brown-Séquard syndrome and an extradural spinal cord compression from tumor. The radiological and cerebrospinal fluid findings are presented and discussed. Radiation treatment was administered to the involved segments of spinal cord in each patient. All patients responded; two for 3 and 7 mo, two for 3 and 4 wk, respectively. There was significant improvement in the quality of life for three of the four patients.

Carcinoma, Small Cell↗
PubMed1981

Power spectral analysis of EEG drug response in the kindled rat brain.

The specificity of procaine as a limbic epileptic focus activator was investigated in rats kindled in the amygdala. Power spectral analysis of spontaneous EEG was employed to assess the effects of two doses of procaine HCl (60 and 100 mg/kg) on the kindled and unkindled amygdala. Analysis revealed a dose-dependent increase in power in the 1--15 c/sec frequency band of the EEG. Power increases were greater in the kindled than in the unkindled amygdala of the same rat, and exceeded power changes induced in unkindled controls. The effects of procaine on the EEG persisted past the day of injection, but returned to baseline by the fifth day. Changes in power over days following an injection of procaine differed in the kindled and unkindled amygdala amygdala of the same rat. The kindled amygdala showed an increase on the day of injection, followed by a steady decline to baseline. The unkindled amygdala showed a delayed rise in power on day 2 and then a decline to baseline levels over days. Comparison of spectral changes induced by drug and by electrically triggered seizures suggested that procaine induces EEG patterns which are seizure-like in the absence of seizures. The data are consistent with the view that procaine may be a useful focus specific activator in the detection of limbic epilepsy.

Amygdala↗
PubMedDate not supplied

Inducibility of rat brain drug-metabolizing enzymes.

Cytochrome P450 from rat brain mitochondrial and microsomal fractions was found to be inducible by 3-methylcholanthrene, both in quantity of enzyme and in activity towards 7-ethoxyresorufin, which is a model substrate for the cytochrome P450 isoform specifically induced by 3-methylcholanthrene. Conversely, a phenobarbital treatment resulted in an induction of the microsomal cytochrome P450 only. On the other hand, the microsomal 1-naphthol-UDP-glucuronosyl transferase and epoxide hydrolase seemed to be non-inducible by 3-methylcholanthrene or by phenobarbital. The toxicological implications of these data are discussed.

Animals↗
PubMedDate not supplied

Drug metabolizing enzymes in the brain and cerebral microvessels.

Several families of brain parenchyma and microvessel endothelial cell enzymes can metabolize substrates of exogenous origin. This xenobiotic metabolism includes functionalization and conjugation reactions and results in detoxication, but also possibly in the formation of pharmacologically active or neurotoxic products. The brain is partially protected from chemical insults by the physical barrier formed by the cerebral microvasculature of endothelial cells, which prevents the influx of hydrophilic molecules. These cells provide also, as a result of their drug-metabolizing enzyme activities, a metabolic barrier against penetrating lipophilic substances. The involvement of these enzymatic activities in neurotoxic events, probably responsible for neuronal dysfunctioning and/or death, neurodegenerative diseases and normal aging, is discussed.

Animals↗
PubMedDate not supplied

Comparative analysis of the genomic DNA terminal regions of the lactococcal bacteriophages from species c2.

In an attempt to compare the cos intergenic region and bordering ORFs from Lactococcus lactis bacteriophages of the species c2, the nucleotide sequence of a 2479-bp fragment containing the cos site of phage P001 DNA was determined and compared with the corresponding regions of phages c2, bIL67 and P6 (partial sequence), which belong to species c2. This comparative analysis revealed that some characteristic features of the cos intergenic region are conserved in all members of species c2. Some of them are specific to species c2, as is the case for a GC-rich repeat in phase with the double helix that is located close to cos. One conserved motif seems to be more general, as it is found in all the cos regions of L. lactis bacteriophages that have been sequenced. It consists in a 4-nt indirect repeat TCAN/NACT located in a 15-bp fragment containing cos. This motif may be related to terminase specificity, as most of the cos asymmetric cleavages identified up to now are located within, or at the border of, these indirectly repeated sequences. Finally, some of the conserved DNA motifs of the species c2 cos-intergenic region seem to be even more general, as they are homologous to the lambda-R sites known to be involved in the maturation and the encapsidation of phage lambda DNA. Our comparative analysis also showed that within c2 phage DNAs, large blocks of sequences, i.e. the intergenic cos region and ORF/17 on the one hand, and ORF/16 on the other hand, evolved as distinct entities, probably by block recombination between phage DNAs of the same species.

Bacteriophages↗
PubMedDate not supplied

[Management of ectopic pregnancies at the university clinic of gynecology and obstetrics in Cotonou (Benin)].

In 1993 and 1994, there were 223 cases of ectopic pregnancy, resolved by surgery, at the University Clinic of Gynecology and Obstetrics of the National Teaching Hospital in Cotonou. This represents 4.57% of the number of deliveries. The study of 204 cases reveals the following characteristics: (i) There are clinical signs: pelvic pains and/or metrorrhagia in 97% of cases; (ii) Diagnosis was often late with a hemoperitoneum and required major intervention (salpingectomy). Ultrasound scanning allowed accurate diagnosis in 30.39% of cases. Celioscopy was necessary in 3.92% of cases; (iii) The life prognosis is usually good (1 death in 204 cases; i.e. 0.49%). The functional prognosis is difficult to estimate. The evolution of medical techniques, with the help of ultrasound scans facilitates early diagnosis and application of modern less traumatic therapies such as endoscopic surgery and conservative treatment.

Adolescent↗