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Dominique Martin

Publications and source records attributed to Dominique Martin.

12 recordsLinked to original sources

Microsurgery in microgravity is possible.

The aim of this experiment was to evaluate the feasibility of a microsurgical procedure in the context of microgravity during parabolic flights. The surgical procedure included the sectioning and repair of a rat sciatic nerve and tail artery with 10/0 monofilament sutures. Both procedures were successful. To date, telesurgery cannot be considered during interplanetary spaceflights. If a surgeon is able to perform microsurgery in microgravity, a physician with basic surgery training will be able to perform basic surgical procedures in space flights.

Animals↗

Evaluation of an impedance threshold device in patients receiving active compression-decompression cardiopulmonary resuscitation for out of hospital cardiac arrest.

AIMS: The purpose of this multicentre clinical randomized controlled blinded prospective trial was to determine whether an inspiratory impedance threshold device (ITD), when used in combination with active compression-decompression (ACD) cardiopulmonary resuscitation (CPR), would improve survival rates in patients with out-of-hospital cardiac arrest. METHODS AND RESULTS: Patients were randomized to receive either a sham (n = 200) or an active impedance threshold device (n = 200) during advanced cardiac life support performed with active compression-decompression cardiopulmonary resuscitation. The primary endpoint of this study was 24 h survival. The 24 h survival rates were 44/200 (22%) with the sham valve and 64/200 (32%) with the active valve (P = 0.02). The number of patients who had a return of spontaneous circulation (ROSC), intensive care unit (ICU) admission, and hospital discharge rates was 77 (39%), 57 (29%), and 8 (4%) in the sham valve group versus 96 (48%) (P = 0.05), 79 (40%) (P = 0.02), and 10 (5%) (P = 0.6) in the active valve group. Six out of ten survivors in the active valve group and 1/8 survivors in the sham group had normal neurological function at hospital discharge (P = 0.1). CONCLUSION: The use of an impedance valve in patients receiving active compression-decompression cardiopulmonary resuscitation for out-of-hospital cardiac arrest significantly improved 24 h survival rates.

Cardiopulmonary Resuscitation↗

Toxicity to Daphnia magna and Vibrio fischeri of Kraft bleach plant effluents treated by catalytic wet-air oxidation.

Two Kraft-pulp bleaching effluents from a sequence of treatments which include chlorine dioxide and caustic soda were treated by catalytic wet-air oxidation (CWAO) at T=463 K in trickle-bed and batch-recycle reactors packed with either TiO2 extrudates or Ru(3 wt%)/TiO2 catalyst. Chemical analyses (TOC removal, color, HPLC) and bioassays (48-h and 30-min acute toxicity tests using Daphnia magna and Vibrio fischeri, respectively) were used to get information about the toxicity impact of the starting effluents and of the treated solutions. Under the operating conditions, complex organic compounds are mostly oxidized into carbon dioxide and water, along with short-chain carboxylic acids. Bioassays were found as a complement to chemical analyses for ensuring the toxicological impact on the ecosystem. In spite of a large decrease of TOC, the solutions of end products were all more toxic to Daphnia magna than the starting effluents by factors ranging from 2 to 33. This observation is attributed to the synergistic effects of acetic acid and salts present in the solutions. On the other hand, toxicity reduction with respect to Vibrio fischeri was achieved: detoxification factors greater than unity were measured for end-product solutions treated in the presence of the Ru(3 wt%)/TiO2 catalyst, suggesting the absence of cumulative effect for this bacteria, or a lower sensitivity to the organic acids and salts. Bleach plant effluents treated by the CWAO process over the Ru/TiO2 catalyst were completely biodegradable.

Animals↗

MECP2 mutations or polymorphisms in mentally retarded boys: diagnostic implications.

BACKGROUND: Among the well characterized X-linked conditions causing mental retardation, mutations in the methyl-CpG-binding protein 2 gene (MECP2) in Xq28 have been found in up to 85% of patients with Rett syndrome, a neurologic disorder which, in addition to other symptoms, severely affects higher cognitive functions in females. Mutations in the MECP2 gene are involved in a broad spectrum of phenotypes from classical Rett syndrome to mild intellectual difficulties in females and neonatal encephalopathy in males. Recently, mutations in the MECP2 gene were reported in males with non-specific mental retardation suggesting that defects in MECP2 could be responsible for up to 2% of X-linked mental retardation. METHODS: We screened by denaturing high-pressure liquid chromatography the entire coding region and flanking intronic sequences of the MECP2 gene in a cohort of 354 mentally retarded males found negative for an expansion across the FRAXA CGG repeat and in a family in which a boy and his sister were mentally retarded. RESULTS: We identified mainly silent polymorphisms within the MECP2 gene, together with four sequence alterations of unknown significance, i.e. three missense mutations (T197M, T228S, and P376S) and one substitution at position -19 in intron 3 (378-19delT). Further familial investigations allowed us to ruled out a pathogenic effect for the intronic variant, the T228S and the P376S missense mutations. CONCLUSIONS: These results confirm that MECP2 mutations in males are far more rare than initially thought and call for a careful evaluation of the pathogenicity of the MECP2 missense mutations identified in mentally retarded males before genetic counseling is proposed to the relatives.

Chromatography, High Pressure Liquid↗

Bone reconstruction of the lower extremity: complications and outcomes.

A study was performed to analyze the results and final outcomes of bone reconstruction of the lower extremity. Twenty-six patients presented with type IIIB open fractures, nine with type IIIC open fractures, and 15 with chronic osteomyelitis. Seven patients underwent primary amputation, and reconstruction was attempted for 43 patients. The mean bone defect size was 7.7 cm (range, 3 to 20 cm). Bone reconstruction was achieved with conventional bone grafts in 16 cases, in association with either local (13 cases) or free (three cases) flaps. Vascularized bone transfer was performed in 24 cases, with either osteocutaneous groin flaps (10 cases), soleus-fibula flaps (12 cases), or osteocutaneous lateral arm flaps (two cases). For three patients, bone reconstruction was performed with a technique that combines the induction of a membrane around a cement spacer with the use of an autologous cancellous bone graft. Infections were observed to be responsible for prolonged hospital stays and treatment failures. The cumulative rates of sepsis were 4.6 percent at 1 week after injury and 62.8 percent at 2 months. Vascular complications were also related to infections and were responsible for four secondary amputations. One patient asked for secondary amputation because of a painful nonfunctional lower limb. Bone healing occurred in 37 of 43 cases, and the average time to union was 9.5 months, with an average of 8.7 procedures. The mean lengths of stay were 49 days for conventional bone grafts and 62 days for vascularized bone grafts. All of the 50 patients were able to walk, with an average time of 14 months. All of the patients with amputations underwent prosthetic rehabilitation. Patients mostly complained about the reconstructed limb (62.8 percent). Joint stiffness was present in 40 percent of the cases. Other long-term complications were pain (nine cases), lack of sensation (five cases), infection (five cases), and pseudarthrosis (one case). However, all of the patients with successful reconstructions preferred their salvaged leg to an amputation. Of 41 patients who were working before the injury, 26 returned to work.

Adolescent↗

[In the hospital setting, what is the patient's role?].

It is crucial for all medical institutions to maximize the selection of their actors in strict accordance to equality. As medical administrators, were are questioned on the problems linked with compartmentalization. Our investigation has allowed us to confirm that the ensemble of actors, including the patient, regulates compartmentalization, and that all in all it works rather well. However, this regulation has a price. It has an impact on organization, the energy used, not to mention the cumbersome side-effects that would be felt. We have chosen to focus our research on the patient's role on regulation by using his/her testimony. The patient is never passive. Adaptation requires real efforts on the patient's part in order to adapt to this new environment, while at the same time economizing his/her strength. The regulation carried out is often standardized. The patient conforms, but against his/her will. Does the patient's admittance to the hospital make him/her a second-class citizen? Our results lead us to believe that the prevailing views advocate that the patient be at the heart of the system remain an objective.

Adaptation, Psychological↗

Involvement of TRPC in the abnormal calcium influx observed in dystrophic (mdx) mouse skeletal muscle fibers.

Duchenne muscular dystrophy results from the lack of dystrophin, a cytoskeletal protein associated with the inner surface membrane, in skeletal muscle. The absence of dystrophin induces an abnormal increase of sarcolemmal calcium influx through cationic channels in adult skeletal muscle fibers from dystrophic (mdx) mice. We observed that the activity of these channels was increased after depletion of the stores of calcium with thapsigargin or caffeine. By analogy with the situation observed in nonexcitable cells, we therefore hypothesized that these store-operated channels could belong to the transient receptor potential channel (TRPC) family. We measured the expression of TRPC isoforms in normal and mdx adult skeletal muscles fibers, and among the seven known isoforms, five were detected (TRPC1, 2, 3, 4, and 6) by RT-PCR. Western blot analysis and immunocytochemistry of normal and mdx muscle fibers demonstrated the localization of TRPC1, 4, and 6 proteins at the plasma membrane. Therefore, an antisense strategy was used to repress these TRPC isoforms. In parallel with the repression of the TRPCs, we observed that the occurrence of calcium leak channels was decreased to one tenth of its control value (patch-clamp technique), showing the involvement of TRPC in the abnormal calcium influx observed in dystrophic fibers.

Animals↗

Prefabricated superficial temporal fascia flap combined with a submental flap in noma surgery.

The authors report their experience with a new procedure: the combination of a prefabricated superficial temporal fascia flap and a submental flap performed in an African hospital on five patients with cheek deformities caused by noma. The prefabricated superficial temporal fascia flap makes the inner lining of the cheek, which is anchored on the peripheral scar tissue. The submental flap is released during the second operation and makes the outer lining. The main advantages are the excellent aesthetic color of this last flap and the short distance between the donor site and the recipient site. Moreover, the submental flap is positioned in a single operation (when the outer-lining reconstruction is performed with a deltopectoralis flap, a third operation is necessary to cut the pedicle). None of the flaps failed, and the functional results were good. The prefabricated superficial temporal fascia flap and submental flap are versatile and reliable flaps, with reasonably long vascular pedicles, that can be used successfully, even under suboptimal conditions in weak patients with huge defects of the face.

Adolescent↗

Reconstruction of short lower leg stumps with the osteomusculocutaneous latissimus dorsi-rib flap.

To avoid a more proximal amputation at the distal part of the thigh, and when the knee joint is preserved, it is possible to lengthen short lower leg stumps. The authors report five cases in which the latissimus dorsi-rib flap was used to achieve a satisfactory functional prosthetic result. The bone segment is long enough to both lengthen the stump and allow its extremities to be firmly fixed to the tibia. Depending on the remaining tibia length, one or two ribs were included in the flap. The procedure allowed achievement of a 5-cm to 9-cm lengthening of the tibia. Bone healing time was 5 to 6 months and allowed prosthetic rehabilitation and ambulating 5 to 7 months after surgery. Final range of motion of the knee joint is compatible with normal ambulating, and the prosthesis is well tolerated. This procedure, which provides a large amount of skin, muscle, and bone, is very effective for reconstruction of short lower leg stumps.

Adult↗