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1.
Ann Chir Plast Esthet ; 68(5-6): e1-e4, 2023 Nov.
Artigo em Francês | MEDLINE | ID: mdl-37778784

RESUMO

The author's experience dates from 1990, during the period when he was in charge of the feminization of the facial skeleton in order to improve the social integration of male transsexual patients. Very quickly, these techniques were extended to genetic women who wanted a more feminine face. This facial skeletal surgery was then supplemented with soft tissue surgery. This skeletal and volumetric surgery has become an important contribution in the search of facial rejuvenation and beauty.


Assuntos
Cirurgia de Readequação Sexual , Transexualidade , Humanos , Masculino , Feminino , Feminização/cirurgia , Face/cirurgia , Transexualidade/cirurgia , Cirurgia de Readequação Sexual/métodos
3.
Micromachines (Basel) ; 12(2)2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33669613

RESUMO

Optimum configuration of a micromixer with two-layer crossing microstructure was performed using mixing analysis, surrogate modeling, along with an optimization algorithm. Mixing performance was used to determine the optimum designs at Reynolds number 40. A surrogate modeling method based on a radial basis neural network (RBNN) was used to approximate the value of the objective function. The optimization study was carried out with three design variables; viz., the ratio of the main channel thickness to the pitch length (H/PI), the ratio of the thickness of the diagonal channel to the pitch length (W/PI), and the ratio of the depth of the channel to the pitch length (d/PI). Through a primary parametric study, the design space was constrained. The design points surrounded by the design constraints were chosen using a well-known technique called Latin hypercube sampling (LHS). The optimal design confirmed a 32.0% enhancement of the mixing index as compared to the reference design.

4.
Ann Chir Plast Esthet ; 62(5): 550-559, 2017 Oct.
Artigo em Francês | MEDLINE | ID: mdl-28911889

RESUMO

Injectable substances known as fillers are used to palliate age-related atrophy and ptosis, and for their so-called "pseudo-lifting" action. They do not replace face and neck lift, but allow it to be postponed or, when injected after surgical lifting, make the result durable. Hyaluronic acid has a predominant and unchallenged place among fillers, well ahead of poly-L-lactic acid or calcium hydroxyapatite. Approaches and injection methods are the same for all fillers, corresponding to those for autologous fat injection, the reference substance, with a few particularities. The substance used, the level of hyaluronic acid reticulation, and the depth of the injection depend on the injection site and intended effect. Effects range from smoothing superficial wrinkles to remodeling whole parts of the face. Complications related to such fillers are well known, especially in the case of hyaluronic acid, where overcorrection is the most frequent. To limit the risk of complications and also to offer each patient the most individually adapted corrections, before any procedure, the plastic surgeon needs to question the patient and perform precise medical examination.


Assuntos
Preenchedores Dérmicos , Rejuvenescimento , Materiais Biocompatíveis/administração & dosagem , Preenchedores Dérmicos/administração & dosagem , Durapatita/administração & dosagem , Humanos , Ácido Hialurônico/administração & dosagem
5.
Ann Chir Plast Esthet ; 62(5): 532-549, 2017 Oct.
Artigo em Francês | MEDLINE | ID: mdl-28886872

RESUMO

For a number of years, a volumetric approach using autologous fat injection has been implemented to improve cosmetic outcome in face-lift procedures and to achieve lasting rejuvenation. Autologous fat as filling tissue has been used in plastic surgery since the late 19th century, but has only recently been associated to face lift procedures. The interest of the association lies on the one hand in the pathophysiology of facial aging, involving skin sag and loss of volume, and on the other hand in the tissue induction properties of grafted fat, "rejuvenating" the injected area. The strict methodology consisting in harvesting, treating then injecting an autologous fat graft is known as LipoStructure® or lipofilling. We here describe the technique overall, then region by region. It is now well known and seems simple, effective and reproducible, but is nevertheless delicate. For each individual, it is necessary to restore a harmonious face with well-distributed volumes. By associating volumetric to the face lift procedure, the plastic surgeon plays a new role: instead of being a tailor, cutting away excess skin, he or she becomes a sculptor, remodeling the face to restore the harmony of youth.


Assuntos
Tecido Adiposo/transplante , Ritidoplastia/métodos , Humanos , Injeções Subcutâneas/métodos , Rejuvenescimento , Transplante de Tecidos/instrumentação , Transplante de Tecidos/métodos
6.
Appl Phys Lett ; 110(20): 201601, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28611484

RESUMO

Chemical etching of SiC was found to proceed in pure water with the assistance of a Pt catalyst. A 4H-SiC (0001) wafer was placed and slid on a polishing pad in pure water, on which a thin Pt film was deposited to give a catalytic nature. Etching of the wafer surface was observed to remove protrusions preferentially by interacting with the Pt film more frequently, thus flattening the surface. In the case of an on-axis wafer, a crystallographically ordered surface was obtained with a straight step-and-terrace structure, the height of which corresponds to that of an atomic bilayer of Si and C. The etching rate depended upon the electrochemical potential of Pt. The vicinal surface was observed at the potential at which the Pt surface was bare. The primary etching mechanism was hydrolysis with the assistance of a Pt catalyst. This method can, therefore, be used as an environmentally friendly and sustainable technology.

8.
Ann Dermatol Venereol ; 135(1 Pt 2): 1S50-8, 2008 Jan.
Artigo em Francês | MEDLINE | ID: mdl-18442664

RESUMO

Autologous fat can be considered to be a gold standard implant by virtue of its volumetric qualities and its action on skin trophicity. Improved techniques have transformed fat injections into reproductible adipocyte grafts with permanent results.


Assuntos
Tecido Adiposo/transplante , Técnicas Cosméticas , Face/cirurgia , Rejuvenescimento , Envelhecimento da Pele/patologia , Adipócitos/transplante , Estética , Face/anatomia & histologia , Feminino , Humanos , Injeções Intradérmicas , Masculino , Complicações Pós-Operatórias , Procedimentos de Cirurgia Plástica , Coleta de Tecidos e Órgãos/métodos
11.
Ann Chir Plast Esthet ; 49(5): 486-502, 2004 Oct.
Artigo em Francês | MEDLINE | ID: mdl-15518948

RESUMO

Products which are non absorbable or slowly absorbable make the correction of facial wasting of any origin possible. These highly efficient products are unfortunately sometimes responsible for complications or even undesirable after effects. In order to avoid this the following are necessary: clinical and histological analysis of facias granulomas, a proposal for guidelines for their use which would predict in situ tolerance.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Procedimentos de Cirurgia Plástica/métodos , Ritidoplastia/métodos , Materiais Biocompatíveis/efeitos adversos , Colágeno/administração & dosagem , Colágeno/efeitos adversos , Granuloma/etiologia , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/efeitos adversos
13.
Science ; 303(5657): 516-20, 2004 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-14739457

RESUMO

In situ measurements of the relative humidity with respect to ice (RHi) and of nitric acid (HNO3) were made in both natural and contrail cirrus clouds in the upper troposphere. At temperatures lower than 202 kelvin, RHi values show a sharp increase to average values of over 130% in both cloud types. These enhanced RHi values are attributed to the presence of a new class of HNO3-containing ice particles (Delta-ice). We propose that surface HNO3 molecules prevent the ice/vapor system from reaching equilibrium by a mechanism similar to that of freezing point depression by antifreeze proteins. Delta-ice represents a new link between global climate and natural and anthropogenic nitrogen oxide emissions. Including Delta-ice in climate models will alter simulated cirrus properties and the distribution of upper tropospheric water vapor.

15.
J Biomech ; 34(1): 105-12, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11425069

RESUMO

This report describes new treadmill ergometer designed to measure the vertical and horizontal ground reaction forces produced by the left and right legs during walking. It was validated by static and dynamic tests. Non-linearity was from 0.2% (left vertical force) to 1.4% (right antero-posterior force). The resonance frequency was from 219 (right vertical direction) to 58 Hz (left medio-lateral direction). A calibration "leg", an air jack in series with a strain gauge, was developed and used to produce force signals comparable to those obtained during human locomotion. The mean differences between the force measured by the calibration leg and treadmill ergometer at 5 km h(-1) were 3.7 N (0.7%) for the left side and 6.5 N (1.2%) for the right. Measurements obtained during human walking showed that the treadmill ergometer has considerable potential for analysing human gait.


Assuntos
Ergometria/instrumentação , Perna (Membro)/fisiologia , Caminhada/fisiologia , Calibragem , Desenho de Equipamento , Humanos , Modelos Biológicos , Dinâmica não Linear
16.
J Radiol ; 82(3 Pt 1): 245-9, 2001 Mar.
Artigo em Francês | MEDLINE | ID: mdl-11287855

RESUMO

PURPOSE: To assess the feasability, the imaging quality and the effectiveness of contrast-enhanced MRA (CE MRA) using a 0.5 Tesla MR unit in the evaluation of internal carotid artery (ICA) stenosis. Materials and Methods. 29 patients underwent CE MRA and selective digital substraction angiography (DSA). All data were reviewed in a blinded fashion by 2 independant observers. Imaging quality was graded as good, moderate but interpretable, and insufficient. Stenosis was graded according to the NASCET classification from grade 1 to 4, with the following thresholds:<30%,<70%,<99% and occlusion. Inter and intra- observer agreement was evaluated using the kappa index. RESULTS: Imaging quality was good for 79 arteries, moderate for 24 and insufficient for 13 (k MRA=0.72 and 0.64 respectively for the right and left ICAs). Interobserver agreement was good with values for right/left ICA of 0.84/0.94, 0.72/0.74 respectively for CE-MRA and DSA. For the comparison between CE MRA and DSA, agreement was also good, with values of 0.74 and 0.64 for both readers. Sensitivity of CE MRA in the detection of hemodynamically significant stenosis (>70%) was of 0.95 and 0.94 and specifity of 0.91 and 0.89 respectively for reader n degrees 1 and reader n degrees 2. CONCLUSION: CE MRA using a 0.5T MR unit is a valuable technique in the evaluation of ICA stenosis.


Assuntos
Angiografia Digital/normas , Estenose das Carótidas/diagnóstico por imagem , Angiografia por Ressonância Magnética/instrumentação , Angiografia por Ressonância Magnética/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital/métodos , Estenose das Carótidas/classificação , Estenose das Carótidas/fisiopatologia , Meios de Contraste , Estudos de Viabilidade , Feminino , Hemodinâmica , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Meglumina , Pessoa de Meia-Idade , Variações Dependentes do Observador , Compostos Organometálicos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Método Simples-Cego
17.
In Vitro Cell Dev Biol Anim ; 36(2): 125-32, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10718369

RESUMO

The purpose of this study is to identify optimal culture conditions to support the proliferation of human macrovascular endothelial cells. Two cell lines were employed: human saphenous vein endothelial cells (HSVEC) and human umbilical vein endothelial cells (HUVEC). The influence of basal nutrient media (14 types), fetal bovine serum (FBS), and mitogens (three types) were investigated in relation to cell proliferation. Additionally, a variety of extracellular matrix (ECM) substrate-coated culture dishes were also tested. The most effective nutrient medium in augmenting cell proliferation was MCDB 131. Compared to the more commonly used M199 medium, MCDB 131 resulted in a 2.3-fold increase in cell proliferation. Media containing 20% FBS increased cell proliferation 7.5-fold compared to serum-free media. Among the mitogens tested, heparin (50 microg/ml) and endothelial cell growth supplement (ECGS) (50 microg/ml) significantly improved cell proliferation. Epithelial growth factor (EGF) provided no improvement in cell proliferation. There were no statistical differences in cell proliferation or morphology when endothelial cells were grown on uncoated culture plates compared to plates coated with ECM proteins: fibronectin, laminin, gelatin, or collagen types I and IV. The culture environment yielding maximal HSVEC and HUVEC proliferation is MCDB 131 nutrient medium supplemented with 2 mM glutamine, 20% FBS, 50 microg/ml heparin, and 50 microg/ml ECGS. The ECM substrate-coated culture dishes offer no advantage.


Assuntos
Endotélio Vascular/citologia , Animais , Bovinos , Técnicas de Cultura de Células , Divisão Celular , Meios de Cultura , Endotélio Vascular/metabolismo , Matriz Extracelular/metabolismo , Heparina/farmacologia , Humanos , Microscopia de Contraste de Fase , Veia Safena/citologia , Veias Umbilicais/citologia
18.
Rev Chir Orthop Reparatrice Appar Mot ; 85(2): 146-55, 1999 May.
Artigo em Francês | MEDLINE | ID: mdl-10392415

RESUMO

PURPOSE OF THE STUDY: The purpose of this study was to present a new treadmill proposed for evaluating gait in children. We analysed differences in ground reaction forces between boys and girls, and we calculated the symmetry index in healthy children. MATERIAL AND METHOD: Time and ground reaction forces of about 30 steps were measured using a new treadmill. The apparatus consists of 2 walking belts which function as two independent treadmills placed side by side, separated by 4 mm. The 2 treadmills were mechanically separated in order to allow independent measurement of the ground reaction forces induced by each lower limb during stance phase. The children (28 boys and 29 girls), all clinically healthy, were divided into three groups according to their height (between 105 and 150 cm). They walked at three different velocities (2.7 km/h, 3.6 km/h and 4.5 km/h according to their height). The graphs representing the subject's measurements were composed of fore-aft, medial-lateral, and vertical parameters. The analysis of these graphs considered stride, stance, double stance and nine specific points. We also calculated the symmetry index of each child. RESULTS: We determined the values of the symmetry index in healthy children. We did not find any significant difference in gait between girls and boys, except for Fz3 at 2.7 kg/h, where Fz3 was higher in girls than in boys. DISCUSSION: We compared our results with those reported in the literature and found that ADAL has a very important advantage in gait analysis in children because it is simple and easily accepted by children.


Assuntos
Teste de Esforço/métodos , Marcha , Fatores Etários , Estatura , Criança , Pré-Escolar , Feminino , Humanos , Pressão , Valores de Referência , Reprodutibilidade dos Testes , Caracteres Sexuais , Processamento de Sinais Assistido por Computador
19.
J Radiol ; 79(12): 1479-85, 1998 Dec.
Artigo em Francês | MEDLINE | ID: mdl-9921450

RESUMO

Clinical, US, CT and MR findings were reviewed in 5 patients with primary epiploic appendagitis (3 men, 2 women, mean age 38 years, age range 29-62 years) seen between December 1994 and December 1997. Diagnosis was reached in all cases with CT, with US in 3 and with MR in 1. Follow-up CT was performed in 2 cases and clinical follow-up in 4. One patient underwent surgery. Initial US, CT or MR examinations revealed a fatty oval-shaped nodule located anteriorly or anterolaterally to the left colon. The greater diameter ranged from 20 to 30 mm. Perinodular lesions with strands of periappendicular fat and thickened parietal peritoneum were visualized in all cases without any other inflammatory process in the abdomen. Symptoms resolved within 4 days in all patients. Signs of fatty inflammatory processes resolved in the 2 patients who had follow-up CTs. Primary epiploic appendagitis has characteristic US, CT and MR features which help guide medical treatment.


Assuntos
Colo/irrigação sanguínea , Diagnóstico por Imagem , Infarto/diagnóstico , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Adulto , Apendicite/diagnóstico , Apendicite/diagnóstico por imagem , Colite/diagnóstico , Colite/diagnóstico por imagem , Colo/diagnóstico por imagem , Divertículo do Colo/diagnóstico , Divertículo do Colo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Infarto/diagnóstico por imagem , Infarto/cirurgia , Laparoscopia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paniculite/diagnóstico por imagem , Peritônio/diagnóstico por imagem , Peritônio/patologia , Peritonite/diagnóstico por imagem , Doenças do Colo Sigmoide/diagnóstico , Doenças do Colo Sigmoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ultrassonografia
20.
J Virol ; 71(8): 5814-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9223470

RESUMO

cpts530, a candidate live-virus vaccine, is an attenuated strain of human respiratory syncytial virus (RSV). It was derived by subjecting a cold-passaged (cp) strain of RSV to a single round of chemical mutagenesis. cpts530 is a temperature-sensitive (ts) mutant that is attenuated in mice and chimpanzees, and its ts phenotype exhibits a high level of stability during replication in both species. In the present study, the complete nucleotide sequence of cpts530 RSV was determined. The five mutations known to be present in the parent cpRSV were retained in its cpts530 derivative, and one additional nucleotide change was identified at nucleotide (nt) 10060, which resulted in a phenylalanine-to-leucine change at amino acid 521 in the large polymerase (L) protein. To determine if this single amino acid substitution was indeed responsible for the ts phenotype of cpts530, it was introduced alone or in combination with the cp mutations into the full-length cDNA clone of the wild-type A2 RSV. Analysis of infectious viruses recovered from mutant cDNAs indicated that this single mutation specified complete restriction of plaque formation of recombinant cp530 in HEp-2 cell monolayer cultures at 40 degrees C, and the level of temperature sensitivity was not influenced by the presence of the five cpRSV mutations. These findings identify the phenylalanine-to-leucine change at amino acid 521 in the L protein as the mutation that specifies the ts phenotype of cpts530. Furthermore, these findings illustrate the feasibility of using the cDNA-based recovery system to analyze and construct defined attenuated vaccine viruses.


Assuntos
Proteína HN , Vírus Sincicial Respiratório Humano/imunologia , Vacinas Sintéticas/genética , Proteínas Virais/genética , Vacinas Virais/genética , Mutação , Temperatura , Vacinas Atenuadas/genética , Proteínas do Envelope Viral
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