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1.
Microsurgery ; 44(1): e31041, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37009759

RESUMO

BACKGROUND: Arteriovenous (AV) looping prior to the lower extremity free flap reconstruction enables better venous drainage in flap circulation, leading to less flap complications and better survival. A two-staged reconstruction including free tissue transfer after AV looping ensures a robust venous drainage of the flap. Arterialization of the AV loop results in less venous problems after the free flap reconstruction. However, major problems of this staged operation include AV loop kinking, heavy compression and loop exposure, leading to AV graft failure and interruption of surgical planning. The purpose of this article is to summarize probable flaws we noticed in conventional two-stage lower limb reconstruction and overcome those problems using the skin paddle-containing vein graft. METHOD: Eight patients with lower limb defects underwent lower limb reconstruction surgery using this technique at our institute. The mean age was 52 years old. Of the eight patients, three of them have the defect due to infection. Three of them was due to trauma and three of them was due to full-thickness burn. Five of the defects located at foot. The other three defects located at heel, knee, and pretibial region. All of them require AV looping because of unavailability of nearby recipient vessels. They all received a two-stage operation, including the first stage AV looping with a skin paddle-containing vein graft and the second stage definite free tissue transfer. RESULTS: The mean defect size was 140 cm2 (72-225). The mean length of AV loops was 17.1 cm (8-25). The mean size of skin paddles for vein grafts was 19.4 cm2 (15-24). The mean size of free ALT flaps 154.4 cm2 (105-252). All eight patients experienced a smooth postoperative course with no major or minor complications. There were no graft thrombosis or graft rupture complications during the vascular maturation period. All eight AV loops survived during maturation. All eight patients progressed to the second stage surgery. Maturation time ranged from 5 to 7 days. Free ALT flap was employed during the second stage reconstruction. All flaps survived at the last follow-up visit. There was no partial flap loss and complications. The mean follow-up time was 12.25 months, ranging from 8 to 17 months. CONCLUSION: The skin paddle-containing vein graft is an effective modification of the regular vein graft for AV looping procedure. The skin paddle prevents the underlying AV loop from compression, kinking and twisting during maturation. It also aids assessing patency of the AV loop and avoids the formation of adhesion between the AV loop and the surrounding tissue.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Pessoa de Meia-Idade , Retalhos de Tecido Biológico/irrigação sanguínea , Resultado do Tratamento , Transplante de Pele , Complicações Pós-Operatórias/cirurgia , Extremidade Inferior/cirurgia , Lesões dos Tecidos Moles/cirurgia
2.
Acta Cardiol Sin ; 39(3): 480-487, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37229329

RESUMO

Background: Radiation ulcers after percutaneous coronary intervention (PCI) are increasingly common. However, their diagnosis, treatment, and prevention strategies have not been well studied. Objectives: To present our experience in the diagnosis, treatment, and prevention of PCI-related radiation ulcers. Methods: Patients diagnosed with PCI-related radiation ulcers were collected. Radiation fields of PCI were simulated using the Pinnacle treatment planning system to confirm the diagnosis. Surgical methods and outcomes were reviewed, and a prevention protocol was developed and evaluated for its effectiveness. Results: Seven male patients with ten ulcers were included. Among the patients, the right coronary artery was the most common target vessel of PCI, and the left anterior oblique was the most commonly used PCI view. Nine ulcers had undergone radical debridement and reconstruction: four smaller ones with primary closure or local flaps, and five with thoracodorsal artery perforator flaps. No new cases were identified in a 3-year follow-up period after implementing the prevention protocol. Conclusions: PCI-related ulcer diagnosis is more evident with radiation field simulation. The thoracodorsal artery perforator flap is an ideal option for back or upper arm radiation ulcer reconstruction. The proposed prevention protocol for PCI procedures was effective in lowering the incidence of radiation ulcers.

3.
Burns ; 49(5): 1039-1051, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35945064

RESUMO

PURPOSE: Accurate assessment of the percentage of total body surface area (%TBSA) burned is crucial in managing burn injuries. It is difficult to estimate the size of an irregular shape by inspection. Many articles reported the discrepancy of estimating %TBSA burned by different doctors. We set up a system with multiple deep learning (DL) models for %TBSA estimation, as well as the segmentation of possibly poor-perfused deep burn regions from the entire wound. METHODS: We proposed boundary-based labeling for datasets of total burn wound and palm, whereas region-based labeling for the dataset of deep burn wound. Several powerful DL models (U-Net, PSPNet, DeeplabV3+, Mask R-CNN) with encoders ResNet101 had been trained and tested from the above datasets. With the subject distances, the %TBSA burned could be calculated by the segmentation of total burn wound area with respect to the palm size. The percentage of deep burn area could be obtained from the segmentation of deep burn area from the entire wound. RESULTS: A total of 4991 images of early burn wounds and 1050 images of palms were boundary-based labeled. 1565 out of 4994 images with deep burn were preprocessed with superpixel segmentation into small regions before labeling. DeeplabV3+ had slightly better performance in three tasks with precision: 0.90767, recall: 0.90065 for total burn wound segmentation; precision: 0.98987, recall: 0.99036 for palm segmentation; and precision: 0.90152, recall: 0.90219 for deep burn segmentation. CONCLUSION: Combining the segmentation results and clinical data, %TBSA burned, the volume of fluid for resuscitation, and the percentage of deep burn area can be automatically diagnosed by DL models with a pixel-to-pixel method. Artificial intelligence provides consistent, accurate and rapid assessments of burn wounds.


Assuntos
Queimaduras , Aprendizado Profundo , Humanos , Queimaduras/diagnóstico , Inteligência Artificial , Hidratação/métodos , Superfície Corporal
4.
PLoS One ; 17(2): e0264139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35176101

RESUMO

A pressure ulcer is an injury of the skin and underlying tissues adjacent to a bony eminence. Patients who suffer from this disease may have difficulty accessing medical care. Recently, the COVID-19 pandemic has exacerbated this situation. Automatic diagnosis based on machine learning (ML) brings promising solutions. Traditional ML requires complicated preprocessing steps for feature extraction. Its clinical applications are thus limited to particular datasets. Deep learning (DL), which extracts features from convolution layers, can embrace larger datasets that might be deliberately excluded in traditional algorithms. However, DL requires large sets of domain specific labeled data for training. Labeling various tissues of pressure ulcers is a challenge even for experienced plastic surgeons. We propose a superpixel-assisted, region-based method of labeling images for tissue classification. The boundary-based method is applied to create a dataset for wound and re-epithelialization (re-ep) segmentation. Five popular DL models (U-Net, DeeplabV3, PsPNet, FPN, and Mask R-CNN) with encoder (ResNet-101) were trained on the two datasets. A total of 2836 images of pressure ulcers were labeled for tissue classification, while 2893 images were labeled for wound and re-ep segmentation. All five models had satisfactory results. DeeplabV3 had the best performance on both tasks with a precision of 0.9915, recall of 0.9915 and accuracy of 0.9957 on the tissue classification; and a precision of 0.9888, recall of 0.9887 and accuracy of 0.9925 on the wound and re-ep segmentation task. Combining segmentation results with clinical data, our algorithm can detect the signs of wound healing, monitor the progress of healing, estimate the wound size, and suggest the need for surgical debridement.


Assuntos
Algoritmos , COVID-19/epidemiologia , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Úlcera por Pressão/diagnóstico , COVID-19/virologia , Humanos , Úlcera por Pressão/diagnóstico por imagem , SARS-CoV-2/isolamento & purificação , Taiwan/epidemiologia
5.
Burns ; 48(6): 1396-1404, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34893371

RESUMO

PURPOSE: To provide evidence of efficacy and postoperative benefit of topical anesthesia (TA) for harvesting split-thickness skin graft (STSG) in an Asian population. MATERIALS AND METHODS: Patients with well-granulating wounds with skin grafting were randomized into TA or general anesthesia (GA) groups. In the TA group, an eutectic mixture of lidocaine and prilocaine (EMLA) was applied. Perioperative heart rate, postoperative donor site pain, adverse effects, patients' satisfaction, duration of surgery, and operation room (OR) stay duration were recorded. RESULTS: Thirty-nine patients (19 males, 20 females; mean age 54.9 ± 17.8) were included. Twenty underwent TA and 19 underwent GA for STSG. The TA group patients had tolerable pain during skin graft harvesting (VAS, 0.85 ± 1.5). Average EMLA exposure duration was 180.3 ± 65.8 min, and the amount applied was 1.72 ± 0.43 g/10 cm2. The TA group had lower donor site pain score at one hour postoperatively (1.34 ± 1.49 vs 3.08 ± 1.90, p = 0.005), lower OR stay duration (36.5 ± 6.5 min vs 65.1 ± 17.2 min, p < 0.001) and less adverse effects than the GA group. CONCLUSION: Harvesting STSG under TA with EMLA is an effective and efficient approach for most Asian patients with less early postoperative donor site pain and fewer adverse effects.


Assuntos
Queimaduras , Prilocaína , Adulto , Idoso , Anestésicos Locais/uso terapêutico , Feminino , Humanos , Lidocaína/uso terapêutico , Combinação Lidocaína e Prilocaína , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/tratamento farmacológico , Prilocaína/uso terapêutico , Estudos Prospectivos , Transplante de Pele
6.
JMIR Med Inform ; 9(12): e22798, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34860674

RESUMO

BACKGROUND: Accurate assessment of the percentage total body surface area (%TBSA) of burn wounds is crucial in the management of burn patients. The resuscitation fluid and nutritional needs of burn patients, their need for intensive unit care, and probability of mortality are all directly related to %TBSA. It is difficult to estimate a burn area of irregular shape by inspection. Many articles have reported discrepancies in estimating %TBSA by different doctors. OBJECTIVE: We propose a method, based on deep learning, for burn wound detection, segmentation, and calculation of %TBSA on a pixel-to-pixel basis. METHODS: A 2-step procedure was used to convert burn wound diagnosis into %TBSA. In the first step, images of burn wounds were collected from medical records and labeled by burn surgeons, and the data set was then input into 2 deep learning architectures, U-Net and Mask R-CNN, each configured with 2 different backbones, to segment the burn wounds. In the second step, we collected and labeled images of hands to create another data set, which was also input into U-Net and Mask R-CNN to segment the hands. The %TBSA of burn wounds was then calculated by comparing the pixels of mask areas on images of the burn wound and hand of the same patient according to the rule of hand, which states that one's hand accounts for 0.8% of TBSA. RESULTS: A total of 2591 images of burn wounds were collected and labeled to form the burn wound data set. The data set was randomly split into training, validation, and testing sets in a ratio of 8:1:1. Four hundred images of volar hands were collected and labeled to form the hand data set, which was also split into 3 sets using the same method. For the images of burn wounds, Mask R-CNN with ResNet101 had the best segmentation result with a Dice coefficient (DC) of 0.9496, while U-Net with ResNet101 had a DC of 0.8545. For the hand images, U-Net and Mask R-CNN had similar performance with DC values of 0.9920 and 0.9910, respectively. Lastly, we conducted a test diagnosis in a burn patient. Mask R-CNN with ResNet101 had on average less deviation (0.115% TBSA) from the ground truth than burn surgeons. CONCLUSIONS: This is one of the first studies to diagnose all depths of burn wounds and convert the segmentation results into %TBSA using different deep learning models. We aimed to assist medical staff in estimating burn size more accurately, thereby helping to provide precise care to burn victims.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34769601

RESUMO

BACKGROUND: Few studies have addressed patient preferences in emergent surgical decision making. AIM OF THE STUDY: Analyzing patient preferences for hand trauma reconstruction to propose a decision-making model. METHODS: A conjoint analysis survey was developed with Sawtooth Software. Three common flaps-i.e., a cross-finger flap (CFF), a dorsal metacarpal artery perforator flap (DMAPF), and an arterialized venous flap (AVF)-were listed as treatment alternatives. Five attributes corresponding to these flaps were recovery time, total procedure, postoperative care methods, postoperative scar condition, and complication rate. Utility and importance scores were generated from the software, and preference characteristics were evaluated using cluster analysis. RESULTS: The survey was completed by 197 participants with hand trauma. Complication risk received the highest importance score (42.87%), followed by scar condition (21.55%). Cluster analysis classified the participants as "conservative," "practical," and "dual-concern". The dual-concern and conservative groups had more foreign laborers and highly educated participants, respectively, than the other groups. Most participants in the conservative and practical groups preferred DMAPF, whereas those in the dual-concern group favored CFF. Our proposed model consisted of shared decision-making and treatment recommendation pathways. CONCLUSION: Incorporating patient preferences into the decision-making model can strengthen patient-centered care. Further research on the applications of the proposed model is warranted.


Assuntos
Tomada de Decisões , Preferência do Paciente , Tomada de Decisão Compartilhada , Humanos , Assistência Centrada no Paciente , Inquéritos e Questionários
8.
Bioact Mater ; 6(6): 1699-1710, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33313449

RESUMO

Many technologies have been developed for breast reconstruction after lumpectomy. Although the technologies achieved promising success in clinical, there are still many shortages hanging over and trouble the researchers. Tissue engineering technology was introduced to plastic surgery that gave a light to lumpectomy patients in breast reconstruction. The unexpected absorption rate, resulting from limited vascularization and low cell survival rate, is a major factor that leads to unsatisfactory results for the previous studies in our lab. In the study, the laminin-modified alginate synthesized by a new method of low concertation of sodium periodate would be mixed with ADSCs and Rg1 in the medium; and then sprayed into a calcium chloride (CaCl2) solution to prepare into microsphere (abbreviated as ADSC-G-LAMS) by bio-electrospray with a power syringe for the mass production and smaller bead size. The developed ADSC-G-LAMS microspheres had the diameter of 232 ± 42 µm. Sustained-release of the Rg1 retained its biological activity. WST-1, live/dead staining, and chromosome aberration assay were evaluated to confirm the safety of the microspheres. In in vivo study, ADSC-G-LAMS microspheres combined with autologous adipocytes were transplanted into the dorsum of rats by subcutaneous injection. The efficacy was investigated by H&E and immunofluorescence staining. The results showed that the bioactive ADSC-G-LAMS microspheres could integrate well into the host adipose tissue with an adequate rate of angiogenesis by constantly releasing Rg1 to enhance the ADSC or adipocyte survival rate to join tissue growth and repair with adipogenesis for breast reconstruction after lumpectomy.

9.
J Clin Med ; 9(11)2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233784

RESUMO

The aim of this study was to investigate the treatment of complicated keloids with helical tomotherapy (HT) and electron beam radiotherapy. From July 2018 to September 2018, 11 patients with 23 keloid lesions treated with HT were enrolled. Additionally, 11 patients with 20 lesions treated with electron beam radiotherapy in the same period were enrolled. Patients in both groups were treated within 24 h after surgical excision of the keloid lesion with 13.5 Gy in three consecutive daily fractions. The median follow-up period was 15 months. The local control rate was 91.3% and 80% in the HT group and the electron beam group, respectively. No acute adverse effects were observed in either group, but most patients exhibited pigmentation. No radiation-induced cancer occurred in these patients up to the time of this report. Pain and pruritus improved for all patients and more obviously for three patients with complicated keloids treated with HT. The measured surface dose was 103.7-112.5% and 92.8-97.6% of the prescribed dose in the HT group and the electron beam group, respectively. HT can be considered an alternative in cases where it is not feasible to use multiple electron fields, due to encouraging clinical outcomes.

10.
J Ophthalmol ; 2020: 5073895, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33489332

RESUMO

PURPOSE: To identify an appropriate surgical indication of epiblepharon by comparing keratopathy and astigmatism outcomes after surgical and medical treatments for epiblepharon in Asian children. METHODS: Children diagnosed with epiblepharon (n = 82, age 5.93 ± 2.76 years) with >6 months of follow-up were enrolled. The clinical presentations and cycloplegic refractive status at the baseline and 3 and 6 months after treatment were compared between surgical (91 eyes from 47 children) and nonsurgical (67 eyes from 35 children) groups. The refractive and keratometric astigmatism at each time point were evaluated with vector analysis methods. For Thibos and Horner's method, the astigmatic power vector was decomposed into horizontal and oblique meridians (J 0 and J 45). However, the treatment-induced astigmatism (TIA) vectors were calculated by Alpins' method and depicted by the AstigMATIC software. RESULTS: In the surgical and nonsurgical groups, the baseline astigmatism magnitude was similar (2.22 ± 1.39 and 2.26 ± 1.46 D, p = 0.87). The rate of complete resolution of keratopathy at 6 months was 71.4% and 11.5%. The astigmatism magnitude in the surgical group differed among baseline and 3 months (2.25 ± 1.23 D) and 6 months postoperatively (1.97 ± 1.28 D) (p = 0.001). Power vector analyses confirmed a nuanced against-the-rule shift in the surgical group. This trend was especially observed in the subgroup of baseline astigmatism >2.0 D. However, the difference in the astigmatism magnitude between surgical and nonsurgical groups, even in highly astigmatic children, was not significant at 6 months. CONCLUSIONS: The improvement of keratopathy in the surgical group was greater than that in the nonsurgical group in consideration of the more advanced severity in the surgery group at baseline. Decreased with-the-rule astigmatism can be observed at 6 months postoperatively, particularly among those with greater baseline astigmatism. However, the amount of change is small, and the outcome does not differ significantly from the nonsurgical treatment. Therefore, surgical indications should majorly base on the severity of symptoms and keratopathy.

11.
Theranostics ; 7(6): 1598-1611, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28529639

RESUMO

Many studies have indicated that loss of the osteoblastogenic potential in bone marrow mesenchymal stem cells (bmMSCs) is the major component in the etiology of the aging-related bone deficit. But how the bmMSCs lose osteogenic capability in aging is unclear. Using 2-dimentional cultures, we examined the dose response of human bmMSCs, isolated from adult and aged donors, to exogenous insulin-like growth factor 1 (IGF-1), a growth factor regulating bone formation. The data showed that the mitogenic activity and the osteoblastogenic potential of bmMSCs in response to IGF-1 were impaired with aging, whereas higher doses of IGF-1 increased the proliferation rate and osteogenic potential of aging bmMSCs. Subsequently, we seeded IGF-1-overexpressing aging bmMSCs into calcium-alginate scaffolds and incubated in a bioreactor with constant perfusion for varying time periods to examine the effect of IGF-1 overexpression to the bone-forming capability of aging bmMSCs. We found that IGF-1 overexpression in aging bmMSCs facilitated the formation of cell clusters in scaffolds, increased the cell survival inside the cell clusters, induced the expression of osteoblast markers, and enhanced the biomineralization of cell clusters. These results indicated that IGF-1 overexpression enhanced cells' osteogenic capability. Thus, our data suggest that the aging-related loss of osteogenic potential in bmMSCs can be attributed in part to the impairment in bmMSCs' IGF-1 signaling, and support possible application of IGF-1-overexpressing autologous bmMSCs in repairing bone defect of the elderly and in producing bone graft materials for repairing large scale bone injury in the elderly.


Assuntos
Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Expressão Gênica , Células-Tronco Mesenquimais/fisiologia , Osteogênese/efeitos dos fármacos , Receptor IGF Tipo 1/biossíntese , Envelhecimento , Células Cultivadas , Humanos
12.
BMC Complement Altern Med ; 17(1): 91, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28153003

RESUMO

BACKGROUND: During the onset of osteoarthritis (OA), certain biochemical events have been shown to accelerate cartilage degradation, including the dysregulation of cartilage ECM anabolism, abnormal generation of reactive oxygen species (ROS) and overproduction of proteolytic enzymes and inflammatory cytokines. The potency of aucubin in protecting cellular components against oxidative stress, inflammation and apoptosis effects are well documented, which makes it a potential candidate for OA treatment. In this study, we aimed to evaluate the protective benefits of aucubin against OA using H2O2 and compression induced OA-like chondrocyte models. METHODS: The effects of aucubin were studied in porcine chondrocytes after 1 mM H2O2 stimulation for 30 min or sustained compression for 24 h. Effects of aucubin on cell proliferation and cytotoxicity of chondrocytes were measured with WST-1 and LDH assays. ROS production was evaluated by the Total ROS/Superoxide Detection Kit. Caspase-3 activity was evaluated by the CaspACE assay system. The levels of apoptosis were evaluated by the Annexin V-FITC apoptosis detection kit. OA-related gene expression was measured by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Total DNA quantification was evaluated by the DNeasy Blood and Tissue kit. Sulfated-glycosaminoglycans (sGAGs) production and content were evaluated by DMMB assay and Alcian blue staining. RESULTS: The results showed that the ROS scavenge effects of aucubin appeared after 1 h of pretreatment. Aucubin could reduce the caspase-3 activity induced by H2O2, and reduced the apoptosis cell population in flowcytometry. In RT-qPCR results, aucubin could maintain ACAN and COL2A1 gene expressions, and prevent IL6 and MMP13 gene up-regulation induced by H2O2 and compression stimulations. In the DMMB assay and Alcian blue staining, aucubin could maintain the sGAG content and protect chondrocytes against compressive stress, but not oxidative stress from H2O2. CONCLUSIONS: These results indicated that aucubin has protective effects in an osteoarthritic chondrocyte model induced by H2O2 and mechanical stimulus.


Assuntos
Condrócitos/efeitos dos fármacos , Glucosídeos Iridoides/uso terapêutico , Osteoartrite/tratamento farmacológico , Agrecanas/genética , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo II/genética , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio , Técnicas In Vitro , Interleucina-6/genética , Glucosídeos Iridoides/toxicidade , Metaloproteinase 13 da Matriz/genética , Osteoartrite/genética , Estimulação Física , Espécies Reativas de Oxigênio/metabolismo , Suínos
13.
Nanoscale Res Lett ; 12(1): 62, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28110445

RESUMO

The use of photodynamic therapy (PDT) in the treatment of brain cancer has produced exciting results in clinical trials over the past decade. PDT is based on the concept that a photosensitizer exposed to a specific light wavelength produces the predominant cytotoxic agent, to destroy tumor cells. However, delivering an efficient light source to the brain tumor site is still a challenge. The light source should be delivered by placing external optical fibers into the brain at the time of surgical debulking of the tumor. Consequently, there exists the need for a minimally invasive treatment for brain cancer PDT. In this study, we investigated an attractive non-invasive option on glioma cell line by using Tb3+-doped LaF3 scintillating nanoparticles (LaF3:Tb) in combination with photosensitizer, meso-tetra(4-carboxyphenyl)porphyrin (MTCP), followed by activation with soft X-ray (80 kVp). Scintillating LaF3:Tb nanoparticles, with sizes of approximately 25 nm, were fabricated. The particles have a good dispersibility in aqueous solution and possess high biocompatibility. However, significant cytotoxicity was observed in the glioma cells while the LaF3:Tb nanoparticles with MTCP were exposed under X-ray irradiation. The study has demonstrated a proof of concept as a non-invasive way to treat brain cancer in the future.

14.
J Mater Sci Mater Med ; 28(1): 18, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28000114

RESUMO

Biomaterials are often added to autologous fat grafts both as supporting matrices for the grafted adipocytes and as cell carrier for adipose-derived stem cells (ADSCs). This in vivo study used an autologous fat graft model to test a lamininalginate biomaterial, adipocytes, and ADSCs in immune-competent rats. We transplanted different combinations of shredded autologous adipose tissue [designated "A" for adipose tissue]), laminin-alginate beads [designated "B" for bead], and ADSCs [designated "C" for cell]) into the backs of 15 Sprague-Dawley rats. Group A received only adipocytes, Group B received only laminin-alginate beads, Group AB received adipocytes mixed with laminin-alginate beads, Group BC received laminin-alginate beads encapsulating ADSCs, and Group ABC received adipocytes and laminin-alginate beads containing ADSCs. Seven-tesla magnetic resonance imaging was used to evaluate the rats at the 1st, 6th, and 12th weeks after transplantation. At the 12th week, the rats were sacrificed and the implanted materials were retrieved for gross examination and histological evaluation. The results based on MRI, gross evaluation, and histological data all showed that implants in Group ABC had better resorption of the biomaterial, improved survival of the grafted adipocytes, and adipogenic differentiation of ADSCs. Volume retention of grafts in Group ABC (89%) was also significantly greater than those in Group A (58%) (p < 0.01). Our findings support that the combination of shredded adipose tissue with ADSCs in laminin-alginate beads provided the best overall outcome.


Assuntos
Adipócitos/citologia , Tecido Adiposo/transplante , Alginatos/química , Materiais Biocompatíveis/química , Laminina/química , Células-Tronco/citologia , Adipogenia , Animais , Sobrevivência Celular , Feminino , Imageamento por Ressonância Magnética , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
15.
Tissue Eng Part A ; 23(5-6): 185-194, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27814669

RESUMO

The use of autologous fat grafting in breast reconstruction still requires optimization. Fat survival and calcification are the main issues that affect the outcomes of the procedure. In this study, a cell-based therapy utilizing laminin-alginate beads (LABs) as carriers was proposed to promote cell survival and adipogenesis by providing short-term physical support and facilitate nutrient diffusion of the implants. Laminin-modified alginate beads were fabricated by immobilizing laminin onto ring-opened alginate, used to encapsulate 3T3-L1 preadipocytes, and evaluated in vitro and in vivo. LABs as preadipocyte carriers showed better biocompatibility and stability than unmodified alginate beads. Preadipocytes in LABs had higher survival rate and enhanced adipogenesis than those in unmodified alginate beads. In vivo studies showed that LABs gradually degraded and the sites were replaced by newly formed fat tissues, and new blood vessels were also observed. 7T-MRI study mimicking clinical fat grafting showed that LABs carrying adipose stem cells improved the results of conventional fat grafts. Therefore, we believe that LABs represent promising cell carriers and can be potentially used for the reconstruction of breasts or other soft tissues in the future.


Assuntos
Adipócitos , Adipogenia , Alginatos/química , Células Imobilizadas , Laminina/química , Células 3T3-L1 , Adipócitos/metabolismo , Adipócitos/transplante , Animais , Células Imobilizadas/metabolismo , Células Imobilizadas/transplante , Feminino , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Ratos Sprague-Dawley
16.
J Biomed Mater Res A ; 104(3): 669-677, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26514819

RESUMO

Extracellular matrix provides both mechanistic and chemical cues that can influence cellular behaviors such as adhesion, migration, proliferation, and differentiation. In this study, a new material, HA-L-Alg, was synthesized by linking developmentally essential ECM constituents hyaluronic acid (HA) and laminin(L) to alginate (Alg). The fabrication of HA-L-Alg was confirmed by FTIR spectroscopy, and it was used to form 3D cell-carrying beads. HA-L-Alg beads had a steady rate of degradation and retained 63.25% of mass after 9 weeks. HA-L-Alg beads showed biocompatibility comparable to beads formed by Alg-only with no obvious cytotoxic effect on the embedded 3T3-L1 preadipocytes. HA-L-Alg encapsulated 3T3-L1 cells were found to have a higher proliferation rate over those in Alg-only beads. These cells also showed better differentiation capacity after 2 weeks of adipogenic induction within HA-L-Alg beads. These results support that HA-L-Alg facilitated cell survival and proliferation, as well as stimulated and maintained cell differentiation. Our results suggest that HA-L-Alg has a great clinical potential to be used as stem cell carrier for adipose tissue engineering. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 669-677, 2016.


Assuntos
Tecido Adiposo/fisiologia , Alginatos/farmacologia , Matriz Extracelular/metabolismo , Ácido Hialurônico/farmacologia , Laminina/farmacologia , Engenharia Tecidual/métodos , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipócitos/ultraestrutura , Adipogenia/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Alginatos/síntese química , Alginatos/química , Animais , Materiais Biocompatíveis/farmacologia , Proteínas de Ligação ao Cálcio , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácido Glucurônico/síntese química , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/síntese química , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Ácido Hialurônico/síntese química , Ácido Hialurônico/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Microesferas , PPAR gama/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Asian Pac J Cancer Prev ; 16(15): 6681-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26434894

RESUMO

BACKGROUND: Metastatic cancer with invasion of skin, soft tissue and skeletal muscle is not common. Examples presenting as soft tissue masses could sometimes lead to misdiagnosis with delayed or inappropriate management. The purpose of current study was to investigate clinical characteristics in the involvement of metastatic cancer. MATERIALS AND METHODS: A total of 1,097 patients complaining of skin or soft tissue masses and/or lesions were retrospectively reviewed from January 2012 to June 2013. Tumors involving skin, soft tissue and skeletal muscle of head and neck, chest wall, abdominal wall, pelvic region, back, upper and lower extremities were included in the study. RESULTS: Fifty-seven (5.2%) patients were recognized as having malignancies on histopathological examination. The most common involvement of malignancy was basal cell carcinoma, followed by cutaneous squamous cell carcinoma, sarcoma and melanoma. The most common anatomical location in skin and soft tissue malignancies was head and neck (52.6% of the malignancies). Four (0.36%) of the malignant group were identified as metastatic cancer with the primary cancer source from lung, liver and tonsil and the most common site was upper extremities. One of them unexpectedly expired during the operation of metastatic tumor excision at the scalp. CONCLUSIONS: Discrimination between benign and malignant soft tissue tumors is crucial. Performance of imaging study could assist in the differential diagnosis and the pre-operative risk evaluation of metastatic tumors involving skin, soft tissue and skeletal muscle.


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Melanoma/patologia , Neoplasias Musculares/patologia , Músculo Esquelético , Neoplasias de Tecido Conjuntivo e de Tecidos Moles/patologia , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Cutâneas/patologia , Neoplasias Tonsilares/patologia , Parede Abdominal , Idoso , Idoso de 80 Anos ou mais , Dorso , Cisto Epidérmico/patologia , Feminino , Neoplasias de Cabeça e Pescoço/secundário , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Neoplasias Musculares/secundário , Neoplasias Epiteliais e Glandulares/secundário , Pelve , Estudos Retrospectivos , Neoplasias Cutâneas/secundário , Parede Torácica , Extremidade Superior
18.
Ann Plast Surg ; 71 Suppl 1: S13-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24284735

RESUMO

The reconstruction of a through-and-through cheek defect with oral commissure involvement can be challenging. When attempting to reconstruct its seam-like structure or to replace its supple lip tissue, postoperative morbidities such as drooling, microstomia, and poor aesthetic appearance can often occur and be difficult to correct. After inspecting the oral commissure, one can observe that the morphology of the upper lip acts as a "drape" hanging over the upper teeth, whereas the lower lip functions similarly to a "dam" holding the constant pour of saliva within the oral cavity. We noted that if we tailored a single fasciocutaneous flap to satisfy these morphologies during reconstruction, not only were the mentioned morbidities of reconstruction greatly diminished, but the reconstructed oral commissure could also spontaneously mimic the contralateral side in form. We presented 10 consecutive patients with cheek defects with concomitant oral commissure involvement, which underwent reconstruction by using a single-folded fasciocutaneous flap. We described how the flaps are tailored to suit the mentioned upper and lower lip morphology. For certain defects, such as a cheek defect with oral commissure involvement, the loss of functional morphology greatly outweighs its anatomical or tissue losses. Our method provides a simple and straightforward surgical option in this area, which was previously perceived as a challenging reconstruction site.


Assuntos
Bochecha/cirurgia , Lábio/cirurgia , Neoplasias Bucais/cirurgia , Retalho Perfurante , Procedimentos de Cirurgia Plástica/métodos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
19.
Ann Plast Surg ; 69(6): 616-21, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23154331

RESUMO

To optimize the outcome of the free fibula flap in mandibular reconstruction, the central portion of the mandible can be divided into upper and lower arches during preoperative evaluation and planning. We present 2 cases requiring mandibular reconstruction with free fibula flap after ameloblastoma excision, to illustrate the "two arches" concept and its applicability in mandibular reconstruction. The postoperative course was uneventful. Follow-up at 24 months postoperative revealed a considerable restoration in facial appearance and provided functional teeth. Recent advances in mandibular reconstruction could be further refined through the application of the "two arches" concept. This approach simplifies surgical planning in selective cases and directs the attention of surgeons to the specific needs of the 2 distinct regions of the mandible during reconstruction.


Assuntos
Ameloblastoma/cirurgia , Fíbula/transplante , Mandíbula/cirurgia , Neoplasias Mandibulares/cirurgia , Reconstrução Mandibular/métodos , Retalhos Cirúrgicos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
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