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Dive into the research topics where Daniel Gehlen is active.

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Featured researches published by Daniel Gehlen.


Plastic and Reconstructive Surgery | 2008

Sources of processed lipoaspirate cells: influence of donor site on cell concentration.

Alexandre Vontobel Padoin; Jefferson Braga-Silva; Pedro Djacir Escobar Martins; Katia Rezende; Antonio Roberto da Rosa Rezende; Bianca Grechi; Daniel Gehlen; Denise Cantarelli Machado

Background: Recently, adipose tissue harvested by liposuction has been identified as a source of processed lipoaspirate cells. The aim of this study was to determine the concentration of processed lipoaspirate cells in adipose tissue obtained by liposuction from different harvest areas in women. Methods: A prospective cross-sectional study was conducted in 25 women in whom liposuction in four or more different zones in the same procedure was indicated. After selective liposuction, the material was sent to the laboratory, where it was processed for extraction of processed lipoaspirate cells, which were separated from the adipose tissue, quantified, and characterized through determination of c-kit expression. The following harvest regions were evaluated: upper abdomen, lower abdomen, trochanteric region, inner thigh, knee, and flank. The cell concentration obtained at each site was compared by analysis of variance for mixed models. Results: A significant difference was found for cell concentration obtained at the different harvest sites. The cell concentration in the lower abdomen was greater than in other areas, but no significant difference was found in relation to the inner thigh. Conclusions: The lower abdomen and the inner thigh may have higher processed lipoaspirate cell concentrations. These sites may turn out to be better sources of adult mesenchymal stem cells.


Journal of Hand Surgery (European Volume) | 2008

A Comparison of the Use of Distal Radius Vascularised Bone Graft and Non-Vascularised Iliac Crest Bone Graft in the Treatment of Non-Union of Scaphoid Fractures

Jefferson Braga-Silva; F. M. Peruchi; G. M. Moschen; Daniel Gehlen; Alexandre Vontobel Padoin

We compared two surgical techniques for the treatment of scaphoid non-union, namely, using distal radius vascularised bone graft and iliac crest non-vascularised bone graft. Eighty patients with symptomatic scaphoid non-union underwent surgical treatment, including 35 patients treated with distal radius vascularised bone graft and 45 treated by iliac crest non-vascularised bone graft. Patients were assessed objectively by examination of wrist range of motion, grip strength and radiographic findings in the postoperative period after a mean time of 2.8 (1.4) (range 1–5.2) years. Similar functional results were obtained with the two techniques. All cases of non-union in the non-vascularised group obtained consolidation in a mean time of 8.89 (2.26) months and in the vascularised group in a mean time of 7.97 (3.06) months. Three cases of consolidation failure occurred in the vascularised group and were related to technical difficulties.


Journal of Hand Surgery (European Volume) | 2008

Can Local Supply of Bone Marrow Mononuclear Cells Improve the Outcome from Late Tubular Repair of Human Median and Ulnar Nerves

Jefferson Braga-Silva; Daniel Gehlen; Alexandre Vontobel Padoin; Denise Cantarelli Machado; Bernardo Garicochea; J. Costa Da Costa

The purpose of this non-randomised retrospective study was to compare nerve regeneration after reconnection with silicone tubes with two different strategies. A total of 44 patients with injured median or ulnar nerves in the forearm were surgically treated. In one group of patients, a silicone tube alone was placed in the nerve gap. In a second group, the silicone tube was filled with autologous bone marrow mononuclear cells obtained by aspiration from the iliac crest. Motor function, sensation and the effect of pain on function were assessed 1 year after surgery. The tubes filled with bone marrow cells showed better recovery than the empty tubes. The use of bone marrow mononuclear cells in addition to tube re-connection may promote better nerve regeneration than conventional tubular repair.


Annals of Plastic Surgery | 2007

Correction of the alveolar gap and nostril deformity by presurgical passive orthodontia in the unilateral cleft lip.

Marcos Ro Jaeger; Jefferson Braga-Silva; Daniel Gehlen; Ronald M. Zuker; David M. Fisher

The use of the nasoalveolar molding technique (NAM) aims to reduce passively the width of the alveolar gap, while improving the AP discrepancy but also focusing on the nose. We developed a within-subjects study in which 11 infants with unilateral lip deformity and varying degrees of alveolar gaps were treated by NAM. Patients included in the study presented alveolar gap at the first appointment to configure the molding device. Alveolar gap was then measured again at the time of lip repair to evaluate the impact of the appliance utilization, and the nostril shape was reassessed to verify the benefit relative to nose symmetry. All patients obtained significant reduction of the alveolar gap. The appliance also facilitated primary nasal positioning, significantly improving nasal symmetry and nostril shape. NAM constitutes an important adjunct to ameliorate the results of primary definitive lip repair while also improving the surgeons ability to provide nasal symmetry.


Annals of Plastic Surgery | 2011

End-to-end versus end-to-side motor and sensory neurorrhaphy in the repair of the acute muscle denervation.

Marcos Ricardo de Oliveira Jaeger; Jefferson Braga-Silva; Daniel Gehlen; Gustavo de Azambuja Pereira-Filho; Claudio Galleano Zettler; Maria Antonieta Lopes de Souza; Javier Román Veas; Alessandra Deise Sebben

Background:The aim of this study was to experimentally compare end-to-end and end-to-side neurorrhaphy in perineural window model after motor nerve lesion, evaluating which one was the most effective to preserve nerves. Also, differences in motor and sensorial nerve regeneration were tested to verify differences in nerve regeneration. Methods:A total of 20 adult male Wistar rats were randomly assigned to 5 groups, and, in each one, a different treatment was performed: besides the control group, and end-to-end or end-to-side graft with motor or sensorial nerves was performed. Silastic sheet was used as a mechanical barrier to prevent innervation from adjacent nerves. After 16 weeks, the specimens were histologically assessed and wet weight was evaluated as a direct parameter of atrophy. Results:The end-to-end neurorrhaphy group presented the best results in terms of mass preservation, but it did not differ significantly from the control group. Motor nerves presented similar results in muscular atrophy. The end-to-side neurorrhaphy group with sensory nerve as donor showed the worst results. Conclusions:The use of sensory nerves to preserve skeletal muscle trophism is not justified, since, according to our model, it affects 50% to 80% of the muscle mass in a period of 16 weeks. End-to-side neurorrhaphy was demonstrated to be an option for re-enervation of a nerve-deprived motor muscle in selected cases.


Acta Ortopedica Brasileira | 2006

Efeitos das células tronco adultas de medula óssea e do plasma rico em plaquetas na regeneração e recuperação funcional nervosa em um modelo de defeito agudo em nervo perfiférico em rato

Jefferson Braga-Silva; Daniel Gehlen; Javier A. Roman; Caroline Menta; Eduardo de Andrade Atkinson; Denise Cantarelli Machado; Christian Viezzer; Gustavo Leivas Barbosa; Cristiane von Werne Baes; Vinicius Duval da Silva; Jaderson Costa da Costa

OBJECTIVES: The effects of the use of bone marrow stem cells (MSC) and platelet-rich plasma (PRP) on peripheral nerves regeneration were assessed by using an established model of sciatic nerve regeneration in rats. METHODS: A 10-mm nervous defect was reconstructed by using a silicone tube filled with MSC, PRP or both. The control group received only the silicone tube. A fifth group was also set, in which the interval was reconstructed by using a dried segment of the nerve. Motor function was tested six weeks after surgery, by means of a gait test. After motor test, the rats were anesthetized, the sciatic nerve and the tube were dried, and the transmission electronic microscopy was performed. RESULTS: The quantitative analysis shows an improved functional recovery in MSC group compared to the other groups. Nervous regeneration was reported for MSC group by means of transmission electronic microscopy with an almost full recovery of the neural anatomy. CONCLUSION: Our results suggest that the use of MSC combined with tubing technique yields a satisfactory recovery of motor function and nervous regeneration.


Plastic and Reconstructive Surgery | 2009

Randomized prospective study comparing reverse and direct flow island flaps in digital pulp reconstruction of the fingers.

Jefferson Braga-Silva; Daniel Gehlen; Fabrício Bervian; Guilherme L. da Cunha; Alexandre Vontobel Padoin

Background: This study compares two therapies for the reconstruction of digital pulp: direct and reverse flow island flaps. Discriminatory sensation and loss of active range of motion were analyzed, with random allocation of nerve suturing. Methods: The authors conducted a randomized prospective study of 122 patients with loss of digital pulp substance in one finger between 1995 and 2005. Patients were divided into two groups: direct flow island flap (n = 62) and reverse flow island flap (n = 60). The main outcomes were the capacity to discriminate between two points, and proximal and distal interphalangeal joint motion loss. Results: In the direct flap group, there was no loss of articular mobility in 51 percent of patients in the proximal interphalangeal joint and in 55 percent of patients in the distal interphalangeal joint. The reverse flap group showed no loss of articular mobility of the proximal interphalangeal joint in 85 percent of patients and of distal interphalangeal joint in 82 percent. Maximum amplitude losses of 10 and 15 degrees were observed only in the direct flap group in proximal interphalangeal joint articulation (p < 0.001), and of 10 degrees in 10 percent of patients in distal interphalangeal joint articulation (p < 0.002). All patients (n = 29) with suturing showed a Weber score less than or equal to 8, whereas only four (13 percent) of those without suturing had a score of 8; the rest had higher Weber scores (p < 0.001). Conclusion: The direct island flap resulted in motion loss in both articulations of the finger but with better discriminatory sensation in comparison with the reverse flap.


Acta Ortopedica Brasileira | 2007

Modelo experimental de lesão raquimedular em ratos com dispositivo para acesso de agentes terapêuticos locais

Jefferson Braga-Silva; Daniel Gehlen; Javier A. Roman; Denise Cantarelli Machado; Jaderson Costa da Costa; Manuel Faúndez; Victor Vieira Orsi; Rafael Braga


Journal of Reconstructive Microsurgery | 2006

Endoscopic Exploration of a Brachial Plexus Injury

Jefferson Braga-Silva; Daniel Gehlen; Carlos Renato Martins Kuyven


Rev. Soc. Bras. Cir. Plást., (1997) | 2005

Mobilização pós-operatória com flexão ativa precoce após reparo de tendões flexores na zona 2

Jefferson Braga-Silva; Pedro Djacir Escobar Martins; Javier A. Roman; Daniel Gehlen

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Jefferson Braga-Silva

Pontifícia Universidade Católica do Rio Grande do Sul

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Denise Cantarelli Machado

Pontifícia Universidade Católica do Rio Grande do Sul

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Javier A. Roman

Pontifícia Universidade Católica do Rio Grande do Sul

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Alexandre Vontobel Padoin

Pontifícia Universidade Católica do Rio Grande do Sul

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Pedro Djacir Escobar Martins

Pontifícia Universidade Católica do Rio Grande do Sul

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Bernardo Garicochea

Pontifícia Universidade Católica do Rio Grande do Sul

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Christian Viezzer

Pontifícia Universidade Católica do Rio Grande do Sul

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Jaderson Costa da Costa

Pontifícia Universidade Católica do Rio Grande do Sul

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Alessandra Deise Sebben

Pontifícia Universidade Católica do Rio Grande do Sul

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Antonio Roberto da Rosa Rezende

Pontifícia Universidade Católica do Rio Grande do Sul

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