Biomedical subjects

S Clemenceau

Publications and source records attributed to S Clemenceau.

6 recordsLinked to original sources

PubMed1992

Fetal and neonatal alloimmune thrombocytopenia: current trends in diagnosis and therapy.

Neonatal thrombocytopenia affects 20-40% of the infants in intensive care units. The frequency of neonatal alloimmune thrombocytopenia (NAIT) is estimated at 1/1500 to 1/5000 live births. The risk of morbidity is significant with 20% neurological sequelae and the death rate is estimated at 10% of affected infants. During recent years considerable efforts have been made to prevent fetal bleeding and to avoid birth trauma, which have significantly changed the natural history of NAIT.

Antigens, Human Platelet↗

PubMed1991

Anterior skull base tumour. The choice between cranial and facial approaches, single and combined procedure. From a series of 78 cases.

In order to define the most adequate surgical procedure to apply on anterior skull base lesions, we reviewed 78 cases of either benign (43 cases) or malignant (35 cases) tumours; they were treated either by a single surgical approach including transfacial approach (TF) in 9 cases, transbasal approach (TB) in 15 cases and fronto-orbital ridge deposition (FORD) in 16 cases or by a combined procedure: TB + TF (28 cases), TB + FORD (10 cases). In 7 cases, a pterional approach was associated to one of these combined procedures. A classification is proposed, based on the tumour extension along the anteroposterior axis: I) anterior to the crista galli; II) anterior to the anterior clinoïd process; III) posterior to the anterior clinoïd process; and along the vertical axis A: below the bone level; B: below the dura level; C: at and above the dura level. This classification appears very useful to choose among the surgical procedures which one is the more appropriate. In type A tumour (N = 8), TF is sufficient while in type B (N = 38) and C (N = 32) a cranial route is always necessary; among the latter, a combined procedure is frequently asked for posterior tumours type II (N = 29) and III (N = 24). However, others parameters such as tumour consistency, vascularization and need for en-bloc removal are also relevant in this choice.

Adolescent↗

PubMed1990

C4 null alleles in childhood onset systemic lupus erythematosus. Is there any relationship with renal disease?

C4 genotyping was performed in 38 unrelated patients with systemic lupus erythematosus (SLE) aged 2-16 years at onset. Null alleles were found in 68% of patients. Ten patients had one null allele at the C4A locus and 11 others had one null allele at the C4B locus. One patient was homozygous for C4A*Q0, 2 homozygous for C4B*Q0 and 1 heterozygous C4A*Q0/B*Q0. The last patient was C4A*Q0B*Q0/B*Q0. Three patients, being heterozygous C2 deficient, had thus a combined C2 and C4 deficiency. A significant increase in C4 null alleles in SLE patients has been reported by different authors who have suggested that the C4 null alleles confer susceptibility to SLE. However, when considering only the 20 patients of French descent, no differences in gene frequencies were found between this group and the French population. Disease patterns were compared in patients with or without null C4. Renal involvement was more frequent in the C4A*Q0 or C4A*Q0/C4A*Q0 patients than in the patients without null C4 (9/11 vs 3/12). These data suggest that differences between these results and those of others might be due to clinical heterogeneity of the disease, as exemplified by the frequency of renal involvement in the different groups. In susceptible individuals the absence of one C4A gene product may predispose the patient to renal involvement.

Adolescent↗

PubMed1990

Intracranial meningiomas in elderly patients. Postoperative morbidity and mortality. Factors predictive of outcome.

We studied retrospectively a series of 96 patients (36 men, 60 women), older than 65 years of age (mean age: 70 +/- 4 years, range 65-82), operated upon for an intracranial meningioma from October 1978 to December 1988. Fifty-two patients (54%) were under 70, 32 between 71 and 75 and 12 over 75 (46%). The tumours were diagnosed for all the patients by CT scan. Thirty-four (35%) were located over the convexity, 24 (25%) in the falx/parasagittal region, 38 (40%) in the base, tentorium and posterior fossa. Neurological and physical conditions were assessed preoperatively and at the closing date in June 1989. Operative mortality was 16% (15/96). Patients were divided into two groups: poor outcome, defined by the death or a post-operative Karnofsky index less than or equal to 70 (n = 36), and good outcome defined by a Karnofsky index of 80 or more (n = 60). The two groups did not differ regarding age, sex ratio, tumour size and peritumoural oedema. The only predictors of poor outcome were poor preoperative general health condition (stage III of the American Society of Anesthesiology classification), (p less than 0.01), poor preoperative neurological condition (Karnofsky's index) (p less than 0.001), and location of the tumour on the base or in posterior fossa (p = 0.02).

Aged↗

PubMed1990

C2 reference typing report.

Thirty samples contributed by seven laboratories to the VIth Complement Genetics Workshop were analyzed by isoelectric focusing and immunoblotting with a specific antihuman C2 antibody for the study of the polymorphism of native, activated and desialated C2. This study allowed to compare almost all the C2 variants so far described and also several 'new variants'. According to our results, the C2 system consists of nine structural variants at the protein level which include the common C2 C, the less common C2 B (in Caucasoids), four rare acidic and three rare basic variants. The polymorphic site for the basic variants is carried by the C2a fragment. Typing of desialated C2 is necessary to identify rare acidic or basic variants, especially the C2 BH and C2 BJ variants which seem difficult to be recognized in the native protein.

Antibodies↗

PubMed1989

[Materials for osteo-dural reconstruction in the cranium. An update].

Materials available for repair of a bony or dural defect at the cranial level are reviewed with particular attention stressed on their qualities and drawbacks for neurosurgical purposes. These materials include autologous or heterologous bone graft and biologically stable or biodegradable implants. No material can demonstrate ideal qualities of biocompatibility and biofunctionality. It should be either perfectly stable biologically and inert or perfectly biodegradable allowing simultaneous new bone reconstruction; moreover, it should be sterilizable, disposable, easy to handle and of low cost. Autologous grafts (iliac bone, split bone flap, pericranium...) have the best features but irradiated heterologous bone can be used instead; the latter needs a particular organization (bone graft bank) to fill the strict conditions of safety, especially regarding the risks of virus transmission. Implants have more recently been developed (acrylic, coral, B.O.P., ceramic, collagen-vicryl...) and present some drawbacks: generally high cost and not well established or insufficient biological properties. The experience of French neurosurgeons is reported from a questionnaire (102 answers) on the most frequently used materials. Autologous bone grafts, and acrylic as bone substitutes and pericranium for dural repair are preferentially used. Some materials, including coral, B.O.P. and collagen-vicryl, have a decreasing utilisation because of poor results especially with regards to bone incorporation and water tightness. Particular techniques (acrylic + teflon, acrylic with pre-op external casting and even non-repair of bone defects) are proposed by some neurosurgeons. New materials still under experimentation are finally presented (lyophilized bovine pericardium, collagen IV, polylactic acid).

Biocompatible Materials↗