Effect of Hyperbaric Oxygen Therapy and Adipocyte Stem Cell on the Viability of Degloving Injury: A Murine Model.

INTRODUCTION: Degloving soft tissue injuries (DSTIs) involve skin and tissue detachment from muscle or fascia. Surgical treatments exist, but they cannot prevent necrosis. OBJECTIVE: Our aim was to investigate the effects of hyperbaric oxygen therapy (HOT) and adipocyte stem cell (ASC) treatment on tissue viability in degloving injuries in a murine model. METHODS: 32 animals were submitted to a degloving flap surgery in the dorsal region and were allocated in four groups (n=8/group): Control: suture only; HOT: 2-hour daily therapy in 100% oxygen at 2.0 ATA for 7 days; ASC: injected with 1x106 stem cells; ASC+HOT: stem cells injection plus HOT therapy. We performed macroscopic measurements, blood flow, histology, and expression of inflammation genes. RESULTS: After 7 days, HOT, ASC, and ASC+HOT groups had significantly more viable tissue compared to Control (97%, 90%, 81% vs. 6%). Viable area ratios were higher in HOT and ASC than Control. Blood flow in the injury's distal region was higher in HOT, ASC, and ASC+HOT compared to Control. Vascular density was higher in HOT and ASC+HOT than Control. Inflammatory cells decreased by 40% in HOT, 50% in ASC+HOT, and 75% in ASC. Gene Cd68 expression was lower in HOT than Control. Il10 expression was lower in HOT but higher in ASC and ASC+HOT than Control. CONCLUSION: This study suggests that the HOT can benefit the degloving injury flap model in the early phase of wound healing, and the association of ASC with HOT could benefit the wound healing in a later phase. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which evidence-based medicine rankings are applicable. This excludes review articles, book reviews, and manuscripts that concern basic science, animal studies, cadaver studies, and experimental studies. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Enrichment of Fat Graft with Association of ASC and Nanofat in an Animal Model.

INTRODUCTION: Fat graft (FG) absorption rate varies from 20 to 80% in two years. Recently, several bioengineering techniques were applied to improve FG retention rate. Numerous studies investigated the use of adipocyte-derived stem cells (ASC) as FG enrichment. However, ASC production is costly, complex, and time-consuming. In contrast, Nanofat, a combination of lipids, stem cells and growth factors, offers a faster, simpler, and more cost-effective alternative for FG enrichment. OBJECTIVE: This study aims to compare the effects of ASC with those of Nanofat, as a viable option in FG enrichment. MATERIAL AND METHODS: Animals were allocated in three groups: Control group (1 mL fat), ASC group (1 mL fat +1x106 ASC), and NnF group (1 mL of fat + 0.3mL NnF). These groups were subdivided in three subgroups (4, 8, and 12 weeks, n = 6/group). We performed ultrasound and macroscopic measurements for FG volume, histology and expression of healing and inflammation genes. RESULTS: At week 12, ASC and NnF groups showed a higher retention of FG when compared to the Control group (51%, 46%, 12% respectively, p < 0.01). Fibrosis was similar in ASC and Nanofat groups. The Nanofat group showed a higher vascular density then the Control group (p < 0.05). Il-10 gene expression was higher, and Mmp9 was lower in the Nanofat group when compared to the ASC and Control groups. CONCLUSION: This study indicates that enriching FG with both ASC and Nanofat led to an increased retention rate of the FG, suggesting that Nanofat might be a promising alternative for FG enrichment. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Use of industrial liquid silicone: a scoping review.

PURPOSE: Illicit cosmetic injections remain highly prevalent and can cause serious complications, including death. We aimed to explore existing literature regarding the use of illicit cosmetic injections globally. METHODS: We searched six databases with no language restriction from inception to 2022. We included all articles focused on adult patients of any gender who received any illicit cosmetic injection. Screening and data extraction followed standards from the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews guidelines. RESULTS: After screening 629 abstracts and 193 full texts, 142 citations were included. We identified articles from 28 countries and three multi-country studies. Most were from high-income (75.3%) and upper-middle-income countries (21.8%). Of all patients whose gender identity was described, 49.9% were transgender women, and 40.8% were cisgender women. The anatomic regions most frequently injected were the buttocks (35%) and the breast (13.3%). The most frequently described complications were granuloma (41.5%), dermatological problems (41.5%), infection (35.9%), and pulmonary complications (34.5%). CONCLUSIONS: We observed the impact of illicit silicone injections, particularly on cisgender women and transgender individuals. Existing barriers must be addressed, including healthcare prejudice and inadequate knowledge about care for gender minorities. This will require educating at-risk groups and enhancing policies to regulate these procedures.

Epidemiological profile trends and cost of pediatric sickle cell disease in Brazil from 2008 to 2022.

OBJECTIVE: This study aimed to investigate the epidemiological trends of Pediatric Sickle Cell Disease (SCD) in Brazil over the period 2008-2022, with a focus on understanding the incidence, mortality rates, and associated healthcare costs. The study explored potential associations between patient characteristics and the occurrence of crises in pediatric SCD cases. METHODS: A cross-sectional study was conducted, analyzing national annual rates of pediatric SCD hospitalizations using data from the FioCruz platform. Descriptive and inferential analyses, including time series and ARIMA regression, were employed. Economic dimensions were assessed using cost categorization. The study followed STROBE reporting guidelines. RESULTS: Data on 81,942 pediatric SCD hospitalizations were collected, with a predominance of crisis-related cases (74.08 %). Males and children under five years old were most affected. Regional disparities were observed, with the Southwest region recording the highest hospitalization rates. ICU costs were higher for crisis-related hospitalizations. Mortality rates were significantly higher for crisis-related cases (p < 0.001), with ARIMA regression indicating a significant association between hospitalizations for crisis-related cases and mortality. CONCLUSION: This study highlights the significant burden of pediatric SCD in Brazil, particularly crisis-related cases, suggesting a need for focused interventions. By prioritizing early detection, equitable access to healthcare, and evidence-based interventions, Brazil can mitigate the burden of SCD and improve patient outcomes. These findings contribute to informing public health policies and interventions aimed at addressing the challenges of pediatric SCD management in Brazil.

Artificial intelligence for predicting response to neoadjuvant chemotherapy for bladder cancer A comprehensive systematic review and meta-analysis.

INTRODUCTION: Neoadjuvant cisplatin-based combination chemotherapy (NAC) followed by radical cystectomy is the standard of care for cisplatin-fit patients harboring muscle-invasive bladder cancer (MIBC). Prediction of response to NAC is essential for clinical decision-making regarding alternatives in case of non-response, and bladder-sparing in case of complete response. This research aimed to assess the performance of machine learning in predicting therapeutic response following NAC treatment in patients with MIBC. METHODS: A systematic review adhering to the PRISMA guidelines was conducted until July 2023. The study integrated articles relating to artificial intelligence and NAC response in MIBC from various databases. The quality of articles was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies 2 (QUADAS-2). A meta-analysis was subsequently performed on selected studies to determine the sensitivity and specificity of machine learning algorithms in predicting NAC response. RESULTS: Of 655 articles identified, 12 studies comprising 1523 patients were included, and four studies were eligible for meta-analysis. The sensitivity and specificity of the studies were 0.62 (95% confidence interval [CI] 0.50-0.72) and 0.82 (95% CI 0.72-0.89), respectively, with a heterogeneity score (I2) of 38.5%. The machine learning algorithms used computed tomography, genetic, and anatomopathologic data as input and exhibited promising potential for predicting NAC response. CONCLUSIONS: Machine-learning algorithms, especially those using computed tomography, genetic, and pathologic data, demonstrate significant potential for predicting NAC response in MIBC. Standardization of methodologic data analysis and response criteria are needed as validation studies.

Effect of ASC Injection in the Inflammatory Reaction in Silicone Implant Capsule: Animal Model.

Background: Capsular contracture is a common complication affecting about 80% of patients who receive radiotherapy after breast reconstruction with silicone prostheses. This study examines the use of adipocyte stem cells (ASCs) to treat capsular contracture. Methods: Thirty rats were operated on to implant a minisilicone prosthesis in the dorsal region. The rats were divided into three groups: control (saline solution injection), radiotherapy (RDT), and RDT + ASC. After 3 months, the capsules were collected and submitted to histological analysis for inflammatory cell presence, vascular density, and collagen fibers, and gene expression of Tnf, Il1rap, Il10, Cd68, Mmp3, and Mmp9 by qPCR. Results: In macroscopic analysis, the RTGO score showed a two-point reduction in RDT + ASC compared with the RDT (P = 0.003). In histological analysis, ASC exhibited less than 50% of inflammatory cells compared with RDT (P = 0.004), which was similar to control. This study demonstrated that Il1rap gene expression was identical in both RDT and RTD + ASC. Compared with control, treatment with ASC reduced Il1rap expression by 30%. Cd68 and Mmp3 expression levels were similar in both the control and RTD + ASC. Conclusion: This study suggests that ASC treatment decreases silicone prosthesis capsule inflammation.

Expanding Global Surgery Education in Brazil: Perspectives after the 35th Brazilian Surgical Congress.

The 35th Brazilian Congress of Surgery marked a turning point for surgical education in the country. For the first time, the Brazilian College of Surgeons included Global Surgery on the main congressional agenda, providing a unique opportunity to rethink how surgical skills are taught from a public health perspective. This discussion prompts us to consider why and how Global Surgery education should be expanded in Brazil. Although Brazilian researchers and institutions have contributed to the fields expansion since 2015, Global Surgery education initiatives are still incipient in our country. Relying on successful strategies can be a starting point to promote the area among national surgical practitioners. In this editorial, we discuss potential strategies to expand Global Surgery education opportunities and propose a series of recommendations at the national level.

Expanding Global Surgery Education in Brazil: Perspectives after the 35th Brazilian Surgical Congress / Expandindo o Ensino de Cirurgia Global no Brasil: Perspectivas após o 35º Congresso Brasileiro de Cirurgia

ABSTRACT The 35th Brazilian Congress of Surgery marked a turning point for surgical education in the country. For the first time, the Brazilian College of Surgeons included Global Surgery on the main congressional agenda, providing a unique opportunity to rethink how surgical skills are taught from a public health perspective. This discussion prompts us to consider why and how Global Surgery education should be expanded in Brazil. Although Brazilian researchers and institutions have contributed to the fields expansion since 2015, Global Surgery education initiatives are still incipient in our country. Relying on successful strategies can be a starting point to promote the area among national surgical practitioners. In this editorial, we discuss potential strategies to expand Global Surgery education opportunities and propose a series of recommendations at the national level.

RESUMO O 35º Congresso Brasileiro de Cirurgia foi marcado por discussões inovadoras para a educação cirúrgica no país. Pela primeira vez, o Colégio Brasileiro de Cirurgiões incluiu a Cirurgia Global na pauta principal do congresso, proporcionando uma oportunidade única de repensar como as habilidades cirúrgicas são ensinadas a partir de uma perspectiva de saúde pública. Essa discussão nos leva a considerar por que e como o ensino da Cirurgia Global deve ser expandido no Brasil. Embora pesquisadores e instituições brasileiras tenham contribuído para a expansão do campo desde 2015, as iniciativas de educação em Cirurgia Global ainda são incipientes em nosso país. Basear-se em estratégias bem-sucedidas pode ser um ponto de partida para promover a área entre os profissionais de cirurgia nacionais. Neste editorial, discutimos potenciais estratégias para expandir as oportunidades de educação em Cirurgia Global e propomos uma série de recomendações a nível nacional.

Treatments of palpebral congenital melanocytic nevus: a systematic review.

PURPOSE: Palpebral congenital melanocytic nevi (PCMN) is a rare congenital skin lesion affecting the eyelids that can lead to cosmetic and psychological concerns and potential health risks such as malignancy. Several authors have analyzed therapeutical strategies to treat PCMN. However, there was no consensus in the literature. This systematic review aimed to evaluate the effectiveness, safety, and success of treatments of PCMN. METHODS: We conducted a systematic review following PRISMA guidelines from October 2022 to April 2023. We included all types of study designs that described or compared PCMN treatments and interventions, as well as histology, recurrence, adverse events, patient satisfaction, and malignant transformation. The search strategy was based on specific search words through the following databases: PubMed, Embase, Latin American and Caribbean Health Sciences Literature (Lilacs), Web of Science, and Scopus. Ongoing studies and gray literature studies were included. RESULTS: We analyzed 25 case reports with 148 participants. The effectiveness, success, and satisfaction with various treatments for PCMN depend on the specific treatment method and the individual patient's case. CONCLUSIONS: Most of the studies showed that surgical procedures (exeresis) are able to treat PCMN in the eyelid. The variability in outcomes emphasizes the importance of further research to better understand the most effective and safe approaches for treating congenital melanocytic nevi.

Adipose tissue-derived stem cells as a therapeutic strategy for enterocutaneous fistula: an experimental model study.

PURPOSE: Enterocutaneous fistula (ECF) is a condition in which there is an abnormal connection between the intestinal tract and the skin. It can lead to high morbidity and mortality rates despite the availability of therapeutic options. Stem cells have emerged as a potential strategy to treat ECF. This study aimed to evaluate the effect of adipose tissue-derived stem cells (ASC) on ECF in an experimental model. METHODS: ECF was induced in 21 Wistar rats, and after one month, they were divided into three groups: control group (C), culture medium without ASC group (CM), and allogeneic ASC group (ASC). After 30 days, the animals underwent macroscopic analysis of ECF diameter and histopathological analysis of inflammatory cells, tissue fibrosis, and vascular density. RESULTS: The study found a 55% decrease in the ECF diameter in the ASC group (4.5 ± 1.4 mm) compared to the control group (10.0 ± 2.1 mm, p = 0.001) and a 59.1% decrease in the CM group (11.0 ± 4.3 mm, p = 0.003). The fibrosis score in the ASC group was 20.9% lower than the control group (p = 0.03). There were no significant differences in inflammation scores among the three groups. CONCLUSIONS: This study suggests that ASC treatment can reduce ECF diameter, and reduction in tissue fibrosis may be a related mechanism. Further studies are needed to understand the underlying mechanisms fully.

Effect of Photobiomodulation With Different Wavelengths on Radiodermatitis Treatment.

Approximately 80% of patients submitted to radiotherapy develop radiodermatitis. Photobiomodulation based on light-emitted diode (LED) is one of the therapeutic strategies for treating inflammation. This study aimed to investigate the effect of the photobiomodulation with two wavelengths, in an acute radiodermatitis animal model. Methods: Twenty rats were submitted to one radiotherapy session. After 15 days, the rats that developed radiodermatitis were divided into control groups, LED-630 nm, LED-850 nm, and LED-630 + 850 nm. The treatment regimen was one session lasting 10 minutes on alternate days for 21 days. We analyzed macroscopy aspects (RTOG scale), vascular density, dermal appendages, VEGF-a, TNF-alpha, MMP-9, and MMP-9 genic expression level. Results: All LED groups revealed a two-point reduction on the radiodermatitis severity grade compared with the baseline classification. Dermal appendage and vascular analysis showed a higher counting in all LED groups compared to control. This study showed dermal appendages twice in the 630/850 nm group compared with the control group. The 630/850 nm group showed six times more arterioles than the control group. Regarding genic expression, this study showed a 10-fold decrease between LED-630 nm versus LED-630 + 850 nm (P = 0.02) interleukin-10 expression and a 12-fold decrease between control versus LED-630 nm (P = 0.006) and LED-850 nm (P = 0.002) in TNF-alpha. Conclusion: LED (630 nm, 850 nm, and 630 nm + 850 nm) showed benefit in the treatment of radiodermatitis, and the association of the 630 nm + 850 nm and 630 nm parameters demonstrated the best macroscopic and microscopic results.

The eight-week concurrent training effect on functional capacity in person living with unilateral transtibial amputation: A randomized controlled trial.

INTRODUCTION: The main causes of amputation include vascular diseases, trauma, cancer, and congenital limb abnormalities. The person with transtibial amputation (TA) is affected by a greater cardiorespiratory, metabolic, and muscular load to walk and perform daily activities. The sedentary lifestyle contributes to the process of chronic non-communicable diseases. The purpose of the study was to compare the effects of eight-week concurrent training (CT) for dependent variables as muscle strength, cardiorespiratory fitness, agility, and postural balance in persons with unilateral TA. METHODS: A eight-week, randomized, controlled trial. Thirty-one people using prostheses for three or more months were selected. They were randomly divided into two groups: Experimental Group (EG; n = 17) - concurrent training and Control group (CG; n = 14) - no training. All patients were evaluated at the baseline and after eight weeks by the functional performance, isokinetic knee evaluation, static and dynamic posturography and cardiopulmonary test. RESULTS: The patients showed improvements in all measures after training (size effect >0.80). CONCLUSION: The main limitations are the sample size, related to the socioeconomic status and availability training and no comparison to other types of training. Eight weeks of CT was effective and favorably modified the dependent variables in TA patients. Therefore, CT is a good option to improve functional performance after the regular rehabilitation program discharge and decreases the metabolic and functional deficits of these patients.

Effects of preoperative magnetic resonance image on survival rates and surgical planning in breast cancer conservative surgery: randomized controlled trial (BREAST-MRI trial).

BACKGROUND: Breast magnetic resonance imaging (MRI) has high sensitivity in detecting invasive neoplasms. Controversy remains about its impact on the preoperative staging of breast cancer surgery. This study evaluated survival and surgical outcomes of preoperative MRI in conservative breast cancer surgery. METHODS: A phase III, randomized, open-label, single-center trial including female breast cancer participants, stage 0-III disease, and eligible for breast-conserving surgery. We compared the role of including MRI in preoperative evaluation versus radiologic exam routine with mammography and ultrasound in breast cancer conservative candidates. The primary outcome was local relapse-free survival (LRFS), and secondary outcomes were overall survival (OS), mastectomy rate, and reoperation rate. RESULTS: 524 were randomized to preoperative MRI group (n = 257) or control group (n = 267). The survival analysis showed a 5.9-years LRFS of 99.2% in MRI group versus 98.9% in control group (HR = 0.72; 95% CI 0.12-4.28; p = 0.7) and an OS of 95.3% in the MRI group versus 96.3% in the control group (HR = 1.37 95% CI 0.59-3.19; p = 0.8). Surgical management changed in 21 ipsilateral breasts in the MRI group; 21 (8.3%) had mastectomies versus one in the control group. No difference was found in reoperation rates, 22 (8.7%) in the MRI group versus 23 (8.7%) in the control group (RR = 1.002; 95% CI 0.57-1.75; p = 0.85). CONCLUSION: Preoperative MRI increased the mastectomy rates by 8%. The use of preoperative MRI did not influence local relapse-free survival, overall survival, or reoperation rates.

Adipose tissue-derived stem cells as a therapeutic strategy for enterocutaneous fistula: an experimental model study

Purpose: Enterocutaneous fistula (ECF) is a condition in which there is an abnormal connection between the intestinal tract and the skin. It can lead to high morbidity and mortality rates despite the availability of therapeutic options. Stem cells have emerged as a potential strategy to treat ECF. This study aimed to evaluate the effect of adipose tissue-derived stem cells (ASC) on ECF in an experimental model. Methods: ECF was induced in 21 Wistar rats, and after one month, they were divided into three groups: control group (C), culture medium without ASC group (CM), and allogeneic ASC group (ASC). After 30 days, the animals underwent macroscopic analysis of ECF diameter and histopathological analysis of inflammatory cells, tissue fibrosis, and vascular density. Results: The study found a 55% decrease in the ECF diameter in the ASC group (4.5 ± 1.4 mm) compared to the control group (10.0 ± 2.1 mm, p = 0.001) and a 59.1% decrease in the CM group (11.0 ± 4.3 mm, p = 0.003). The fibrosis score in the ASC group was 20.9% lower than the control group (p = 0.03). There were no significant differences in inflammation scores among the three groups. Conclusions: This study suggests that ASC treatment can reduce ECF diameter, and reduction in tissue fibrosis may be a related mechanism. Further studies are needed to understand the underlying mechanisms fully.

Treatments of palpebral congenital melanocytic nevus: a systematic review

Purpose: Palpebral congenital melanocytic nevi (PCMN) is a rare congenital skin lesion affecting the eyelids that can lead to cosmetic and psychological concerns and potential health risks such as malignancy. Several authors have analyzed therapeutical strategies to treat PCMN. However, there was no consensus in the literature. This systematic review aimed to evaluate the effectiveness, safety, and success of treatments of PCMN. Methods: We conducted a systematic review following PRISMA guidelines from October 2022 to April 2023. We included all types of study designs that described or compared PCMN treatments and interventions, as well as histology, recurrence, adverse events, patient satisfaction, and malignant transformation. The search strategy was based on specific search words through the following databases: PubMed, Embase, Latin American and Caribbean Health Sciences Literature (Lilacs), Web of Science, and Scopus. Ongoing studies and gray literature studies were included. Results: We analyzed 25 case reports with 148 participants. The effectiveness, success, and satisfaction with various treatments for PCMN depend on the specific treatment method and the individual patient's case. Conclusions: Most of the studies showed that surgical procedures (exeresis) are able to treat PCMN in the eyelid. The variability in outcomes emphasizes the importance of further research to better understand the most effective and safe approaches for treating congenital melanocytic nevi.

A modified hydrogel production protocol to decrease cellular content.

PURPOSE: To analyze the cytotoxicity and cell in porcine-derived decellularized skin matrix. METHODS: We analyzed the effect of multiple decellularization processes by histological analysis, DNA quantification, and flow cytometry. Subsequently, we analyzed the most appropriate hydrogel concentration to minimize cytotoxicity on fibroblast culture and to maximize cell proliferation. RESULTS: After the fourth decellularization, the DNA quantification showed the lowest DNA concentration (< 50 ng/mg). Histological analysis showed no cell components in the hydrogel. Moreover, hematoxylin and eosin showed a heterogeneous structure of collagen fibers. The best hydrogel concentration ranged from 3 to 25%, and there was no significant difference between the 24 hours and seven days. CONCLUSIONS: The process of hydrogel production was effective for removing cells and DNA elements. The best hydrogel concentration ranged from 3 to 25%.

Paramedian forehead flap in the treatment of nasal, non-melanoma skin cancer: a cross-sectional study.

INTRODUCTION: nose is the central point of the face and vulnerable to the occurence of non-melanoma skin cancer (NMSC), impacting on appearance. The paramedian forehead flap (PMFF) is considered the best option to treat extensive nasal defects. The objective of this study is to present the experience on PMFF for nasal reconstruction in the treatment of NMSC of a cancer referral center. METHODS: retrospective study was carried out through data from medical records of patients who underwent nasal reconstruction with PMFF due to NMSC at the Cancer Institute of the State of São Paulo (ICESP). RESULTS: 111 patients were identified, mostly ederly, with comorbidities and on initial tumors (T1 and T2). Basal cell carcinoma (BCC) was the predominant histological type. Dorsum and tip were the most affected subunitis. In addition to skin coverage, reconstruction of the lining and structural framework was also performed in half of the cases. Second intention healing was the technique of choice in closing the donor area. Pedicle division ocurred predominantly in the second operation and the median time to complete reconstruction was 6 months. There were low complication rates. CONCLUSIONS: the PMFF is safe and effective to treat nose NMSC, even in cases of high complexity. Since the treatment time can be prolonged and impact on quality of life, it is essential to emphasize and discuss this aspect with the patients before surgery.

Comparison of three different strategies to treat sciatic nerve regeneration: an experimental study.

PURPOSE: To compare the effect of vein conduit filled with adipose tissue stem cells (ASC) on peripheral nerve injury regeneration. METHODS: We analyzed 30 male Wistar rats surgically submitted to a 5-mm gap on the sciatic nerve. Then, the animals were divided into three groups: nerve autografting (AG, n=10), autogenous inverted glycerol-conserved vein (VG, n=10), and autogenous inverted glycerol-conserved vein + ASC (VASCG, n=10). The study endpoints were neuromotor functional analysis, gastrocnemius muscle weight, and sciatic nerve graft histomorphometry analysis. In the histologic analysis, we added a control group (naïve nerve). RESULTS: Regarding functional analysis (Walking tract- score), the findings at week 3 showed a difference between the AG and the VG (-96.6 vs. -59.6, p=0.01, respectively) and between the VG and the inverted vein + VASCG (-59.9 vs. -88.92, p=0.02). At week 12, this study showed a difference between the AG and the VG (-64.8 vs. -47.3, p=0.004, respectively), and also a difference between the VG and the VASCG (-47.3 vs. -57.4, p=0.02, respectively). There was no difference in the histomorphometry analysis (nerve diameter, Schwann cells counting). The gastrocnemius muscles on the intervention side were more atrophic when compared to the gastrocnemius muscles on the control side. CONCLUSIONS: Our results suggested better functional recovery in the inverted vein group when compared to control group, and inverted vein + ASC group.

Comparison of three different strategies to treat sciatic nerve regeneration: an experimental study

Purpose: To compare the effect of vein conduit filled with adipose tissue stem cells (ASC) on peripheral nerve injury regeneration. Methods: We analyzed 30 male Wistar rats surgically submitted to a 5-mm gap on the sciatic nerve. Then, the animals were divided into three groups: nerve autografting (AG, n=10), autogenous inverted glycerol-conserved vein (VG, n=10), and autogenous inverted glycerol-conserved vein + ASC (VASCG, n=10). The study endpoints were neuromotor functional analysis, gastrocnemius muscle weight, and sciatic nerve graft histomorphometry analysis. In the histologic analysis, we added a control group (naïve nerve). Results: Regarding functional analysis (Walking tract- score), the findings at week 3 showed a difference between the AG and the VG (-96.6 vs. -59.6, p=0.01, respectively) and between the VG and the inverted vein + VASCG (-59.9 vs. -88.92, p=0.02). At week 12, this study showed a difference between the AG and the VG (-64.8 vs. -47.3, p=0.004, respectively), and also a difference between the VG and the VASCG (-47.3 vs. -57.4, p=0.02, respectively). There was no difference in the histomorphometry analysis (nerve diameter, Schwann cells counting). The gastrocnemius muscles on the intervention side were more atrophic when compared to the gastrocnemius muscles on the control side. Conclusions: Our results suggested better functional recovery in the inverted vein group when compared to control group, and inverted vein + ASC group.

A modified hydrogel production protocol to decrease cellular content

Purpose: To analyze the cytotoxicity and cell in porcine-derived decellularized skin matrix. Methods: We analyzed the effect of multiple decellularization processes by histological analysis, DNA quantification, and flow cytometry. Subsequently, we analyzed the most appropriate hydrogel concentration to minimize cytotoxicity on fibroblast culture and to maximize cell proliferation. Results: After the fourth decellularization, the DNA quantification showed the lowest DNA concentration (< 50 ng/mg). Histological analysis showed no cell components in the hydrogel. Moreover, hematoxylin and eosin showed a heterogeneous structure of collagen fibers. The best hydrogel concentration ranged from 3 to 25%, and there was no significant difference between the 24 hours and seven days. Conclusions: The process of hydrogel production was effective for removing cells and DNA elements. The best hydrogel concentration ranged from 3 to 25%.