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Biomedical subjects

P Mercier

Publications and source records attributed to P Mercier.

At least 91 records · Page 5Linked to original sources
PubMed1996

Results of surgery for lumbar spinal stenosis in patients aged 80 years or more. A retrospective study of thirty-four cases.

As life expectancy increases and spinal imaging techniques improve, surgery is being increasingly viewed as a therapeutic alternative for symptomatic lumbar spinal stenosis in patients older than 80 years. Thirty-four patients (21 men and 13 women) who had surgery for lumbar spinal stenosis in our department between 1979 and 1994 were studied retrospectively. The most common initial symptoms were walking-related disorders (n = 29) and sciatica or femoral neuralgia (n = 34). All 34 patients underwent laminectomy at one or more levels. Ten patients also had a herniated disk. There were no deaths and only two patients had serious complications (persistent foot drop in one and left-sided hemiplegia in the other). Results were evaluated immediately after surgery and after three and 12 months. The overall result on pain and walking-related disorders was good in 53% of cases, acceptable in 32%, and poor in 15%. Our data suggest that surgery is a reasonable alternative in symptomatic elderly patients who are in good general health. Satisfactory results can be obtained although disabling complications can occur.

Age Factors↗
PubMed1996

[Vascular complications during surgery of lumbar disk herniation. Apropos of 3 personal cases and 37 cases from a national investigation].

Three personal cases of iatrogenic vascular complications (two arterial wounds and one arteriovenous fistula) induced by lumbar herniation surgery led to a French national investigation among vascular and neurosurgical units where 37 other such cases have been discovered over 10 years (1984-1994). In 23 cases, the initial symptomatology was collapses by arterial (22 cases) or venous (one case) hemorrhage requiring emergency vascular repair surgery; in 17 cases an arterio-venous fistula was found in a period varying from a few hours to 5 years after surgery; it was revealed by cardiac failure, lower limb edema or abdominal thrill. Among the 40 cases, 77% occurred at the L4-L5 level; the mortality was 5%, and the morbidity was 27%. Origin, causes and prevention are discussed.

Adult↗
PubMed1996

[Experimental vaccination of broiler chickens against Newcastle disease in Burkina Faso using thermotolerant LaSota/A300 and V4/276 coated-millet vaccines].

Vaccination against Newcastle disease with the thermotolerant LaSota/A300 and V4/276 coated-millet vaccines was tried in Ouagadougou, Burkina Faso, by feeding 298 European broiler chickens exhibiting maternal antibodies. Opportunistic infections, such as colibacteriosis, decimated 70-81% of the three vaccinated groups and 24% of control, before being eradicated by antibiotic therapy. The surviving chickens were challenged two months after vaccination with the Hertz 33/56 virus strain. This resulted in 100% deaths in the control group, 78% in birds vaccinated with the V4/276, 7% in birds fed with LaSota/A300, and in no death in the group given both vaccines at one week interval. These last two groups also exhibited high titres of 1HA antibodies before the challenge. The lyophilized LaSota/A300 and V4/276 vaccines kept high viral titres after 8-34 days' ambient temperature exposure during the cool season in Ouagadougou.

Animals↗
PubMed1996

[Mandibular ridge augmentation with hydroxylapatite and its extension].

The results of 5 years follow-up of 84 cases of mandibular residual ridge augmented with hydroxlapatite (HA), followed by ridge extension, are reported. The first surgical procedures, subperiosteal HA insertion, and the second stage of total lowering of the floow of the mouth, vestibuloplasty and skin graft are detailedly described. The ridge is augmented by the first surgery, disturbance of the fraenums of the lip, buccal and tongue and muscles are eliminated by the second surgery, to increase denture retention and stability, improve wear resisting of tissue covered over the artifical ridge and eliminate pain and uncomfort when wearing denture. The results of five years follow-up show that two stages reconstruction are better than HA insertion only. HA is a kind of ideal material of bone replacement, which is not resorbed in most cases.

Adult↗
PubMed1995

Melanoblast/melanocyte early marker (MelEM) is a glutathione S-transferase subunit.

We have biochemically characterized the antigen recognized by the melanoblast/melanocyte early marker (MelEM) monoclonal antibody (Mab) which labels early melanoblasts and melanocytes in the avian embryo [1]. While among the neural crest derivatives MelEM Mab is strictly specific for the melanocytic lineage, some endodermal derivatives such as hepatocytes react with this Mab. Since MelEM Mab immunoprecitates a protein of the same relative mass from both liver extracts and melanocytes, we immunopurified MelEM protein from liver extract of quail embryos at 10 days of incubation. The N-terminal sequence of this protein being blocked, we determined three internal peptide sequences. Our study reveals that the MelEM protein is an Alpha class subunit of glutathione S-transferase which is common to hepatocytes and to neural crest-derived pigment cells during their differentiation.

Amino Acid Sequence↗
PubMed1995

Cadaver kidney transplantation: ethics and consent.

Organ transplantation began to develop soon after the Second World War. The constant progress made in organ transplantation has resulted in an increase in the number of operations carried out. The laws governing transplantation are often drawn up to deal with the de facto situation in a particular country. The study focuses on Guideline 1 adopted by 44th World Health Assembly (resolution WHA 44-25) concerning consent in cadaver kidney transplantation. The discussion of the question of consent is based on a comparative study of the laws regarding kidney transplantation in the countries of what is known as Greater Europe. The points of discussion presented are not offered with a view to advocating a system where soliciting the consent of the family would be considered as ethically necessary. Given the current legal constraints, the presumed consent procedure, with consultation of the family would appear to be more appropriate.

Cadaver↗
PubMed1995

Anastomosis between the internal carotid and vertebral artery in the neck.

We report a case of anastomosis between the internal carotid and vertebral a. in the cervical region. This anatomic variation is due to incomplete migration during embryogenesis of the branchial aa., collaterals of the dorsal aorta, towards the ventral aorta. It does not involve persistence of a type I proatlantal a., as described by Lasjaunias. Such anastomoses must be recognised since they may modify surgical tactics in the context of endarterectomy for carotid stenosis.

Angiography↗
PubMed1995

Failures in ridge reconstruction with hydroxyapatite. Analysis of cases and methods for surgical revision.

Misuse of hydroxyapatite for ridge reconstruction leads to problems in denture construction. The object of this article is to analyze cases that have failed to provide acceptable results and to discuss methods for surgical revision. The group under study was made of 30 patients treated originally in different centers (with one exception) with 34 attempts at ridge reconstruction for the 27 mandibular cases and 3 maxillary ones. Only two mandibular cases received a skin graft. Three major problems were identified: (1) improper location of hydroxyapatite over the vestibular instead of the lingual or palatal sides of the ridge (27 of 30 cases); (2) poorly defined ridge form (26 of 30 cases); and (3) submucosal hydroxyapatite extrusion (15 of 30 cases). Splints or binding agents did not prevent these complications. Mandibular revision was accomplished by adding hydroxyapatite over the old material and onto the lingual side of the ridge. At a second stage, the floor of the mouth was lowered. As the vestibule was extended, material in excess was removed before skin graft application. Maxillary revision involved material removal from the vestibular side to allow the lining mucosa of the vestibule to return to a normal position.

Alveolar Ridge Augmentation↗
PubMed1995

Gastric emptying of solid food in edentulous patients.

Whether mastication of food by teeth is a physiological contributor in the process of nutrient digestion remains a debatable issue. In this study we sought to determine whether mastication could influence the gastric emptying of solid food. In 8 edentulous patients, we measured the gastric emptying of a test meal ingested with or without their dental prostheses. Clinical dental evaluation and Helkimo chewing test were first performed to verify that the mastication deficiency was adequately corrected by the dental prostheses. A mixed meal containing ten cubes (1.5 cm) of beef liver labeled with 99mTc and mixed in a chicken stew was ingested by the subjects and followed by gamma camera external scintigraphy. The gastric emptying rate of the 99mTc-labeled liver was similar whether the meal was ingested with the denture properly inserted, allowing normal mastication of the liver cubes, or whether the food was swallowed unmasticated in the absence of functional prostheses (Tlag = 60 +/- 5 vs. 58 +/- 11 min, p = NS; T1/2 = 73 +/- 21 vs. 55 +/- 10 min, p = NS; Tlag+T1/2 = 133 +/- 19 vs. 114 +/- 17 min, p = NS). These results show that gastric trituration and emptying of solid food was not facilitated by prior mastication.

Dentures↗
PubMed1995

HLA-DRB1 alleles associated with rheumatoid arthritis in southern France. Absence of extraarticular disease despite expression of the shared epitope.

OBJECTIVE: Extraarticular rheumatoid arthritis (RA) is almost unknown in Marseille in southern France. We investigated whether this was due to rare expression of the HLA-DRB1 shared epitope. METHODS: HLA-DRB1 alleles were characterized in 73 patients with RA and 108 controls by polymerase chain reaction amplification and oligonucleotide hybridization. RESULTS: In patients with RA, 76% expressed the shared epitope (46% DR1, 45% DR4). Four HLA-DRB1 alleles were positively associated with disease: DRB1*0101, DRB1*0401, DRB1*0404, DRB1*0405. Patients with double dose shared epitope had the most severe articular damage, but no extraarticular disease. CONCLUSION: In Marseille, 76% of patients with RA are shared epitope positive. Still, most do not develop extraarticular RA. This may be caused by the low frequency of HLA-DRB1*0401 in this population.

Adult↗
PubMed1995

[Transpetrosal approaches to the clivus. Surgical anatomy, challenges and limitations].

Radical excision of skull base tumors is a real challenge for neurosurgeons. The need to preserve the nerves and the vessels in the area lead us to use lateral approaches, if the lesion lies lateral to the cavernous portion of the carotid artery and behind the petrous apex. Lateral approaches are classified into two groups: ventrolateral approaches (in front of the cochlea) and dorsolateral approaches (with or without resection of the bony labyrinth). The three surgical approaches studied were the subtemporal preauricular infratemporal, the subtemporal anterior transpetrosal, and the combined supra and infratentorial presigmoid approach. The approaches were performed on adult cadaver heads fixed in formolin. The technique, the exposure, the modifications and extensions, as well as the problems of reconstruction are discussed.

Dissection↗
PubMed1995

[Infection after long lasting procedure in neurosurgery].

A retrospective study was performed to appreciate the frequency of infectious complications following long duration neurosurgical procedure with or without antibiotic prophylaxis. Among the 6,702 surgical procedures studied 87 lasted more than 6 hours. The frequency of wound infections of those 87 patients was 13.8% whereas it was only 1.43% for the whole group. There was no significant statistical difference between patients who were treated with antibiotics and those who were not. The high frequency of infection by Klebsiella (25% of the identified germs) was caused by a contamination of the intensive care unit. Duration of the surgical procedure, synthetic material and repetitive procedures are important points to analyse when comparing the different publications. If any antibiotic prophylaxis is to be used, it must be adapted to the microbial environment of each care unit.

Anti-Bacterial Agents↗
PubMed1995

Expression pattern of two otx genes suggests a role in specifying anterior body structures in zebrafish.

We isolated two zebrafish sequences containing a homeobox related to orthodenticle (otd), a gene expressed in the developing head of Drosophila. One of these is clearly homologous to Otx1, a homeobox gene previously reported to be expressed in the developing rostral brain of the mouse. We termed this zebrafish gene otx1. The second gene is not as closely related to Otx1 and is equally divergent from Otx2, a second homeobox gene expressed in the developing rostral brain of the mouse. We termed it otx3, even if a corresponding murine Otx3 gene has not been reported yet. Both genes are expressed in early-gastrula zebrafish embryos in the involuting presumptive anterior mesendoderm. With the extension of the body axis, the expression domain of both genes extends to neuroectodermal regions fated to become fore- and mid-brain. From this stage the expression domains of the two genes differ slightly from each other but both cover the rostral brain with a sharp posterior boundary coinciding with that between midbrain and hind-brain. This late expression closely corresponds to that of the murine Otx1 gene, whereas the earliest expression of both zebrafish otx genes is different from that of Otx1 and reminiscent of that of Otx2 in the mouse. In this light, the zebrafish otx1 and otx3 genes appear to share some expression features of both murine Otx1 and Otx2. It will be of considerable interest to study the specific role of the various genes of the otx family in the development of the zebrafish brain regions. The peculiar spatio-temporal pattern of these genes during early zebrafish gastrulation suggests a role of this gene family in interactions between anterior mesendoderm and neuroectoderm.

Amino Acid Sequence↗
PubMed1995

[Arterial vascularization of the foot. Its importance in operations of revascularization of the lower limb].

Vascularization of the foot was studied using 50 intraoperative arteriograms on single legs and 50 cadaver injections. Arterial vascularization was shown to depend on supramalleolar anastomoses, the primary plantar arch and secondary arches. Anastomotic routes are essential for the permeability of femorotibial bypasses and cicatrization of distal trophic lesions when only one tibial artery remains permeable and must be revascularized.

Aged↗
PubMed1994

Vertebral hemangioma. Spontaneous spinal canal remodeling after fracture.

STUDY DESIGN: The patient in this report had a fracture of a hemangiomatous vertebra with a fragment protruded into the canal and without neurological signs. There was a 12 month follow-up. RESULTS: After conservative treatment, there were no neurologic signs, a good fusion, and natural remodeling of the spinal canal. CONCLUSIONS: The risk of a hemangiomatous vertebra fracture with a fragment retropulsed into the spinal canal and without neurologic signs is low. Also, a remodeling of the spinal canal can occur, as after a burst fracture.

Aged↗
PubMed1994

Surgical anatomy and dissection of the petrous and peripetrous area. Anatomic basis of the lateral approaches to the skull base.

The purpose of this study is to review the topographic anatomy of the petrous and peripetrous structures, with emphasis on the relationships important to the lateral approaches to the posterior and lateral skull base. Surgical exposure of the clivus, the posterior aspect of the petrous bone, the ventral aspect of the brain stem, and of all the intradural structures in the area, remains difficult because of the presence of the so-called "petrous and peripetrous complex". However, the lateral approach to the skull base is the most suitable approach if the lesion lies lateral to the cavernous portion of the internal carotid artery, and of course if the lesion develops laterally behind the petrous apex. Consequently, neurosurgeons should be familiar with the anatomy of the intrapetrous cavities and their contents, and with the relationships in the area. Middle cranial fossa dissections (dry and fresh specimens) allow us to study the anatomical relationships between the intrapetrous carotid artery, the facial nerve, the porus, the cochlea, the geniculate ganglion and the petrosal nerves, the trigeminal ganglion and nerve, the auditory tube and the middle ear. While briefly reviewing some approaches (anterior petrosectomy, sub-temporal preauricular infratemporal fossa approach, pre-sigmoid approach), we explore the concept of the approach and the limitations of surgical technique and exposure.

Humans↗