PubMed Health⌕ Search

Biomedical subjects

E Briand

Publications and source records attributed to E Briand.

18 recordsLinked to original sources
PubMed2005

Self-assembled monolayers of peptide nucleic acids on gold surfaces: a spectroscopic study.

We have characterized self-assembled monolayers (SAMs) of thiol-derivatized peptide nucleic acid (PNA) chains adsorbed on gold surfaces by using reflection absorption infrared spectroscopy (RAIRS) and X-ray photoemission spectroscopy (XPS) techniques. We have found that the molecular orientation of PNAs strongly depends on surface coverage. At low coverage, PNA chains lie flat on the surface, while at high coverage, PNA molecules realign their molecular axes with the surface normal and form SAMs without the need of co-immobilization of spacers or other adjuvant molecules. The change in the molecular orientation has been studied by infrared spectroscopy and it has been confirmed by atomic force microscopy (AFM). PNA immobilization has been followed by analyzing the N(1s) XPS core-level peak. We show that the fine line shape of the N(1s) core-level peak at optimal concentration for biosensing is due to a chemical shift. A combination of the above-mentioned techniques allow us to affirm that the structure of the SAMs is stabilized by molecule-molecule interactions through noncomplementary adjacent nucleic bases.

Chromatography, High Pressure Liquid↗
PubMed2000

Can one lung ventilation prevent air embolism in the lung injury victim?

The current literature indicates that patients with hilar lung injury who are receiving positive pressure ventilation are at risk for systemic air embolism, but no studies have yet tested an alternative to the current management: immediate thoracotomy and hilar clamping. We wanted to demonstrate that one lung ventilation of the uninjured lung protects against the formation of arterial air embolism in the presence of contralateral hilar lung injury.In 6 juvenile swine, the right bronchus was selectively ventilated, and ultrasound of the abdominal aorta was used to detect air emboli. The hilum of the left lung was stabbed with a scalpel; after a brief period of monitoring to detect air emboli, the tip of the endotracheal tube was withdrawn into the trachea and the left lung ventilated.Air emboli were detected in 2 animals. The air emboli did not form while the lung was isolated, but they did appear immediately when the endotracheal tube was withdrawn into the trachea. Air was also noted in the chambers of the heart and coronary arteries, and led to fibrillation and death.One lung ventilation appears to protect against arterial air embolism in unilateral hilar lung injury. (Curr Surg 57:349-353)

Journal Article↗
PubMed2000

Kinematics of prehension and pointing movements in C6 quadriplegic patients.

AIMS: C6 quadriplegic patients lack voluntary control of their triceps muscle but can still perform reaching movements to grasp objects or point to targets. The present study documents the kinematic properties of reaching in these patients. MATERIALS AND METHODS: We investigated the kinematics of prehension and pointing movements in four quadriplegic patients and five control subjects. Prehension and pointing movements were recorded for each subject using various object positions (ie different directions and distances from the subject). The 3D motion was analyzed with Fastrack Polhemus sensors. RESULTS: During prehension tasks the velocity profile of control subjects showed two peaks (go and return); the first velocity peak was scaled to the distance of the object. In quadriplegic patients there was a third intermediary peak corresponding to the grasping of the object. The amplitude of the first peak was slightly smaller than in control subjects. Velocity was scaled to the distance of the object, but with a greater dispersion than in control subjects. Total movement time was longer in quadriplegics because of the prolonged grasping phase. There were few differences in the pointing movements of normal and quadriplegic subjects. The scapula contributed more to the reaching phase of both movements in quadriplegic patients. CONCLUSION: In spite of some quantitative differences, the kinematics of the hand during reaching and pointing in quadriplegic patients are surprisingly similar to those of control subjects. Spinal Cord (2000) 38, 354 - 362.

Adult↗
PubMed2000

Quantitative and kinetic evolution of wound healing through image analysis.

To define a healing function based on parameters measured on digitized images of wounds, and to use it to compare the rate of healing of two skin graft donor sites, one treated with petrolatum gauze (Pg) and the other with a topical preparation containing alginates (A). Digital photographs of donor sites (depth 0.6 mm) taken every two days between day 6 and day 12 were analyzed blind using the same algorithm, following changes in color and homogeneity. Analysis of variance was used to identify those parameters that changed during healing. The healing function was constructed using measurements made in six patients (group 1) randomly chosen from ten requiring skin grafts, and was applied and validated using data from the remaining four patients (group 2). The results given by this healing function were compared with those provided by principal component analysis. The most significant healing parameters were those measuring wound homogeneity, and our healing function reflects how these change with time. The time-dependent curves of the function calculated for groups 1 and 2 matched well enough to be considered as being derived from the same set of measurements. The results given by this healing function explained, by analogy, the meaning of the first principal component of principal component analysis. From day 6 to day 12, the healing function followed the same time-course for the Pg and A treatments, but healing was achieved significantly earlier (4 days, p < 0.03) with A. This suggests that the effect of A on wound healing is achieved in the first six days, before the visual changes from epidermalization are analyzable.

Administration, Topical↗
PubMed1999

Microbiology in sudden infant death syndrome (SIDS) and other childhood deaths.

The usefulness of post-mortem microbiology in the assessment of sudden unexpected deaths in infants and children has been debated by many pathologists. In our centre, microbiological investigations have been part of the post-mortem protocol for investigation of sudden deaths in infants and children for the past 12 years. The objective of this study was to review the microbiological findings for infants and children examined by our unit during the past 4 years in relation to gross and histological findings of the autopsy and the medical and social histories of the children. We reviewed 57 consecutive sudden deaths in infants and children examined by our Referral Centre between November 1994 and October 1998. These 57 sudden deaths were aged from 1 day to 4 years and 9 months including 40 cases of sudden infant death syndrome (SIDS) and 17 non-SIDS deaths. Results of the microbiological investigations of tissues and body fluids were assessed during the case review with reference to histological shock signs, severe gastric aspiration, and signs of acute thymic involution. Bacteria alone or in association with viruses were identified in 45/57 (79%) cases including 34/40 (85%) SIDS. The most frequent bacterial isolate was Escherichia coli (27), and the virus identified most frequently was enterovirus (8). C-reactive protein was increased in 10 out of the 42 cases tested including 8/32 (25%) SIDS. Significant gastric content aspiration was found in 17/57 (29.8%) including 13/40 (32.5%) SIDS. Histological signs of shock were present in 33/55 (60%) cases including 22/39 SIDS (56.4%). The microbiological findings were positive for 27/33 (81.8%). We conclude that post-mortem microbiology is essential in sudden death investigation. The conclusion that a death is unexplained if no microbiology was done is not valid, even if in some cases it may be difficult to know precisely in what way the pathogen contributed to the death.

Autopsy↗
PubMed1999

Biceps-to-triceps transfer in tetraplegia. The medial route.

Eight tetraplegic patients (13 elbows) were treated by biceps-to-triceps transfer. To avoid the risk of radial nerve injury, we chose a medial routing of the biceps. The mean follow-up after surgery was 17.8 months (range, 4-47 months). No complications were encountered. Active extension of the elbow was achieved in each case. The mean postoperative active range of motion of the elbow was 6 degrees extension and 137 degrees flexion. After the biceps-to-triceps transfer mean extension torque of the elbow was 3.7 Nm and mean flexion torque was 10 Nm. In eight elbows in which it was measured, there was a 47% reduction in elbow flexion power. Nevertheless no patient complained about that reduction, and all of them were satisfied.

Adult↗
PubMed1999

[Main abdominal flap donor sites].

The main flaps derived from the abdominal wall are described, indicating the following points for each one: vascular anatomy, the cutaneous and/or muscle territory of the flap, the arc of rotation, the main applications and finally comments concerning certain specific anatomical or technical points. Rectus abdominis flaps are by far the most frequently used in routine clinical practice for mammary reconstruction and cover of the thorax, abdomen or groin areas. Groin flaps are also frequently used, either as pedicled flaps to cover defects of the upper extremity or abdomen, or as free flaps, especially for mandibular reconstructions.

Abdominal Muscles↗
PubMed1998

[Information campaign on child care practices: measure of the effects on sleep position and sudden infant death syndrome].

BACKGROUND: To define the prevalence of the child care practices questioned in the sudden infant death syndrome (SIDS), especially the prone sleep position, before and after an information campaign. To evaluate the effects of this action on the postneonatal mortality. METHOD: A population survey was conducted in four French departments among mothers of infants born in March 1994 and March 1995 and aged 5 days and 2.5 months. A specific information campaign was conducted among health personnel in October 1994. RESULTS: After the information campaign, the prevalence of prone sleeping dramatically decreased at both ages studied: from 6.8% to 1.1% at 5 days and from 24.5% to 7.2% at 2.5 months. Duvets were used less whereas the other practices (bed sharing, using pillow, breastfeeding, maternal smoking) did not change. The postneonatal SIDS rate significantly decreased, from 1.1 p. 1000 live births in 1994 to 0.7 in 1995, the mortality from others causes also declined; the overall postneonatal mortality was 2.7 p. 1000 before the action and 2.1 p. 1000 after. CONCLUSION: The sleeping position which is the main factor questioned in SIDS was modified, and the postneonatal mortality decreased. The specific action conducted for the present epidemiological research is probably not the only contributor in these positive results.

Adult↗
PubMed1996

[Sleeping position, prevention of sudden death syndrome and gastroesophageal reflux].

Based on results of epidemiological studies, dorsal or lateral sleeping positions are now recommanded in the prevention of sudden infant death syndrome (SIDS). This raises an ethical question about the attitude towards the ventral positioning therapy for gastroesophageal reflux (GOR). The consensus conference considers that the ventral position should only be recommanded in GOR when the benefit appears to outweigh the risk of SIDS that it induces. The conference proposes that for infants with simple uncomplicated reflux, sleeping in the prone position should not be introduced in the first line treatment. Prone positioning should be restricted to complicated cases resistant to dietary and medical measures.

Gastroesophageal Reflux↗
PubMed1996

Enterovirus in sudden unexpected deaths in infants.

BACKGROUND: Conventional approaches to virus detection failed to provide convincing evidence of a viral etiology in sudden unexplained deaths in infants (SUDI). Many viruses may not have been detected by the routinely used methods; among them enteroviruses (EV) have seldom been found in SUDI. METHODS: In this study EV were sought directly in stools, in pharyngeal and tracheal samples and in myocardial and lung tissues, by using a nested PCR; they were also sought indirectly by detecting IgM antibodies with a new capture immunoassay. Twenty-four SUDI cases were divided into two groups: Group I, certainly associated with; or Group II, not associated with clinical, biologic or histologic signs of viral infection. RESULTS: EV were found in stools but their prevalence was not significantly different between Group I and Group II (20 and 22.2%, respectively). On the contrary EV were detected in respiratory tract and/or lung samples in 53.8% of infants of Group I and in none of Group II. Anti-EV IgM antibodies were detected in 55.5% of infants of Group I and in none of Group II. CONCLUSIONS: These results indicate that EV infection may be specifically associated with the subgroup of SUDI with viral signs, raising the question of its role in this condition.

Base Sequence↗
PubMedDate not supplied

[Sudden newborn infant death in maternity. Anatomo-clinical study of 31 cases].

PATIENTS AND METHODS: All cases of sudden and unexpected death occurring in maternity were studied over a period of 6 years (1985-1991). Anamnestic data, results of clinical examination of the body and findings of bacterial screening of body fluids or tissues were collected. The results at necropsy were also collected following the protocol used, with parental consent, in all cases of sudden infant death syndrome. RESULTS: There were 31 cases of sudden and unexpected death. Of these, 48% occurred before the 24th hour of life, 68% before the 36th hour and 84% before the 72nd hour. The majority of death occurred at night (55% between midnight and 6 AM, 90% between 9 PM and 9 AM). Analysis of the data provided a precise cause of death in 25 cases (81%), and a probable cause in 4 cases (13%). The major causes were perinatal anoxia, generally associated with massive amniotic inhalation (16 cases), and maternal-fetal infection (9 cases). No cause was found in 2 cases. Despite the fact that the death occurred unexpectedly, half of the newborns showed warning signs, some hours before the event. These signs were either not detected or ignored. CONCLUSION: The incidence of sudden death in neonates is 0.15 to 0.36/1,000 live births. Its causes are generally correlated with common neonatal diseases. Its occurrence at night and the existence of warning signs raise questions concerning the care of neonates in maternity.

Amniotic Fluid↗