ABSTRACT 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.

RESUMO RACIONAL: A enzima metilenotetrahidrofolato redutase está envolvida na síntese de DNA através do metabolismo do folato. A inibição da sua atividade aumenta a suscetibilidade a mutações, danos e metilação aberrante do DNA, o que altera a expressão gênica de supressores tumorais e proto-oncogenes, potenciais fatores de risco para câncer de esôfago. OBJETIVOS: Investigar a associação entre os polimorfismos metilenotetrahidrofolato redutase 677C>T e metilenotetrahidrofolato redutase 1298A>C e a suscetibilidade ao câncer de esôfago, avaliando a distribuição de genótipos e haplótipos entre casos e controles, bem como investigar a associação de polimorfismos com características clínicas, epidemiológicas e sobrevida. MÉTODOS: Avaliaram-se 109 pacientes com câncer de esôfago submetidos à esofagectomia, enquanto 102 indivíduos constituaram o grupo controle. O DNA genômico do sangue periférico foi isolado e submetido à amplificação por reação em cadeia da polimerase em tempo real. A associação entre os polimorfismos e o risco de desenvolver câncer de esôfago foi avaliada por regressão logística. RESULTADOS: Não houve associação dos polimorfismos e haplótipos metilenotetrahidrofolato redutase 677C>T e metilenotetrahidrofolato redutase 1298A>C com a suscetibilidade ao câncer de esôfago. Pacientes com câncer de esôfago portadores do polimorfismo metilenotetrahidrofolato redutase 677TT apresentaram maior risco de morte pela doença. Para o genótipo TT homozigoto polimórfico, o risco de morte aumentou significativamente em comparação com os casos do genótipo selvagem metilenotetrahidrofolato redutase 677CC (referência) (p=0,045; RR=2,22, IC95% 1,02–4,83). CONCLUSÕES: Não houve associação entre os polimorfismos metilenotetrahidrofolato redutase 677C>T e metilenotetrahidrofolato redutase 1298A>C e o risco de suscetibilidade ao câncer de esôfago. O genótipo homozigoto polimórfico metilenotetrahidrofolato redutase 677TT associou-se a um maior risco de óbito após tratamento cirúrgico para câncer de esôfago.

ABSTRACT BACKGROUND: The enzyme methylenetetrahydrofolate reductase is engaged in DNA synthesis through folate metabolism. Inhibiting the activity of this enzyme increases the susceptibility to mutations, and damage and aberrant DNA methylation, which alters the gene expression of tumor suppressors and proto-oncogenes, potential risk factors for esophageal cancer. AIMS: This study aimed to investigate the association between methylenetetrahydrofolate reductase 677C>T and methylenetetrahydrofolate reductase 1298A>C polymorphisms and susceptibility to esophageal cancer, by assessing the distribution of genotypes and haplotypes between cases and controls, as well as to investigate the association of polymorphisms with clinical and epidemiological characteristics and survival. METHODS: A total of 109 esophageal cancer patients who underwent esophagectomy were evaluated, while 102 subjects constitute the control group. Genomic DNA was isolated from the peripheral blood buffy coat followed by amplification by polymerase chain reaction and real-time analysis. Logistic regression was used to assess associations between polymorphisms and the risk of developing esophageal cancer. RESULTS: There was no association for methylenetetrahydrofolate reductase 677C>T and methylenetetrahydrofolate reductase 1298A>C polymorphisms and haplotypes, with esophageal cancer susceptibility. Esophageal cancer patients carrying methylenetetrahydrofolate reductase 677TT polymorphism had higher risk of death from the disease. For polymorphic homozygote TT genotype, the risk of death significantly increased compared to wild-type genotype methylenetetrahydrofolate reductase 677CC (reference) cases (p=0.045; RR=2.22, 95%CI 1.02–4.83). CONCLUSIONS: There was no association between methylenetetrahydrofolate reductase 677C>T and methylenetetrahydrofolate reductase 1298A>C polymorphisms and esophageal cancer susceptibility risk. Polymorphic homozygote genotype methylenetetrahydrofolate reductase 677TT was associated with higher risk of death after surgical treatment for esophageal cancer.

Abstract Introduction: The increase in the incidence of pancreatic and biliary cancers has attracted the search for methods of early detection of diseases and biomarkers. The authors propose to analyze new findings on the association between microbiota and Pancreatic Ductal Adenocarcinoma (PDAC) or Cholangiocarcinoma (CCA). Methods: This systematic review was carried out according to the items of Preferred Reports for Systematic Reviews and Protocol Meta-Analysis (PRISMA-P). This study was registered by the Prospective Register of Systematic Reviews (PROSPERO), identification code CRD42020192748 before the review was carried out. Articles were selected from the PUBMED, EMBASE, and Cochrane databases. Results: Most studies (86.67%) used 16s rRNA as a sequencing method. The main comorbidities found were diabetes mellitus, systemic arterial hypertension, and dyslipidemia. Many studies were limited by the small number of participants, but the biases were mostly low. There was very little concordance about the composition of the microbiome of different sites, for both case and control groups when compared to other studies’ results. Bile sample analysis was the one with a greater agreement between studies, as three out of four studies found Escherichia in cases of CCA. Conclusion: There was great disagreement in the characterization of both the microbiota of cases and control groups. Studies are still scarce, making it difficult to adequately assess the data in this regard. It was not possible to specify any marker or to associate any genus of microbiota bacteria with PDAC or CCA.

RESUMO Introdução: 40% dos pacientes submetidos à radioterapia após reconstrução de mama por implante de prótese de silicone podem desenvolver encapsulamento da prótese. Diversas estratégias já foram testadas para prevenir a contratura da cápsula com resultados insatisfatórios. Este estudo analisou o efeito do antileucotrieno (AL) tópico na formação de contratura capsular em ratos com implantes de silicone associados à irradiação. Métodos: Foram implantados blocos de silicone na região dorsal em 20 ratas fêmeas, espécie Wistar com peso variando de 200-250g. Os animais foram divididos em dois grupos: controle (injeção de solução fisiológica 0,9% no tecido ao redor do implante) e grupo intervenção (injeção de 10mg de AL no tecido ao redor do implante). Imediatamente após a cirurgia os animais foram irradiados com dose única de 10Gy. Após dois meses, coletamos amostras de cápsulas para análise histológica e análise da expressão gênica dos seguintes biomarcadores: iNOS, VEGF-a e MMP-9. Resultados: A densidade vascular foi menor no grupo AL quando comparado ao grupo controle (55,4±30,0 vs. 81,8±26,7, p=0,05, respectivamente). Da mesma forma, o VEGF-a teve o mesmo comportamento (grupo controle - 0,34±0,1 vs. grupo Al - 0,02±0,001, p=0,04). Conclusão: Este estudo sugeriu que o tratamento com AL diminui a angiogênese em animais submetidos a implantes de silicone e submetidos à radioterapia

ABSTRACT Introduction: 40% of patients undergoing radiotherapy after breast reconstruction by silicone prosthesis implant may develop prosthesis encapsulation. Several strategies have already been tested to prevent capsule contracture with unsatisfactory results. This study analyzed the effect of topical antileukotriene (AL) on capsular contracture formation in rats with silicone implants associated with irradiation. Methods: Silicone blocks were implanted in the dorsal region in 20 female rats Wistar with weights ranging from 200-250g. The animals were divided into two groups: control (injection of 0.9% saline solution into the tissue around the implant) and intervention group (injection of 10mg of AL into the tissue around the implant). Immediately after surgery, the animals were irradiated with a single dose of 10Gy. After two months, we collected capsule samples for histological analysis and gene expression analysis of the following biomarkers: iNOS, VEGF-a and MMP-9. Results: Vascular density was lower in the AL group when compared to the control group (55.4±30.0 vs. 81.8±26.7, p=0.05, respectively). Similarly, VEGF-a had the same behavior (control group - 0.34±0.1 vs. group Al - 0.02±0.001, p=0.04). Conclusion: This study suggested that treatment with AL decreases angiogenesis in animals submitted to silicone implants and underwent radiotherapy.

ABSTRACT Purpose: To assess the effects of adipocyte-derived stem cell (ASC)-injection on the survival of surgical flaps under ischemia in diabetic rats. Methods: Diabetes was induced in 30 male Wistar rats using streptozotocin (55 mg/kg). After eight weeks, epigastric flap (EF) surgery was performed. The animals were divided into control (CG), medium-solution (MG), and ASC groups. The outcomes were: the survival area (SA), the survival/total area rate (S/TR), and expression levels (EL) of genes: C5ar1, Icam1, Nos2, Vegf-a. Results: In the ASC group, compared to CG, we observed improved flap SA (CG-420 mm2 vs. ASC-720 mm2; p=0.003) was observed. The S/TR analysis was larger in the ASC group (78%) than the CG (45%). This study showed an increase in the Vegf-a EL in the ASC group (2.3) vs. CG (0.93, p=0.0008). The Nos2 EL increased four-fold in the ASC group compared to CG, and C5ar1 EL decreased almost two-fold in the ASC group vs. the CG (p=0.02). There was no difference among the groups regarding Icam1 EL. Compared to the MG, the ASC group had a bigger flap SA (720 mm2 vs. 301 mm2, respectively), a bigger S/TR (78% vs. 32%, p=0.06, respectively) and increased EL of Vegf-a (2.3 vs. 1.3, respectively). No difference between ASC-group and MG was seen regarding Nos2 (p=0.08) and C5ar1 (p=0.05). Conclusions: This study suggests that ASCs increase the survival of EF under IR in diabetic rats.

RESUMO Racional: A lesão celular da pancreatite aguda (PA) envolve sobrecarga de cálcio, regulada pela atividade da Cálcio ATPase de membrana (PMCA), Cálcio ATPase do Retículo (SERCA2) e pelo Trocador Sódio Cálcio (NCX1). A melatonina (antioxidante) e o Dissacarídeo Trissulfatado (acelerador do NCX1) poderiam reduzir a lesão celular na PA. Objetivo: Avaliar a expressão do RNAm da SERCA2 e NCX1 em modelo animal de pancreatite aguda tratados com melatonina e/ou dissacarídeo trissulfatado (DT). Método: Ratos Wistar foram divididos em grupos: 1) sem pancreatite aguda; 2) com pancreatite aguda por taurocolato; 3) PA e Melatonina; 4) PA e DT; 5) PA e Melatonina com DT. Amostras de tecido foram colhidas para detecção dos níveis de RNAm da SERCA2 e NCX1 por PCR. Resultados: Houve aumento da expressão do RNAm da SERCA2 no grupo com PA tratados com Melatonina, porém sem aumento de expressão do NCX1. O DT não afetou os níveis de SERCA2 e NCX1. O tratamento conjunto com Melatonina e DT diminuiu a expressão da SERCA2. Conclusões: O efeito da Melatonina é restrito ao aumento da expressão da SERCA2. O DT não tem ação na expressão gênica, porém sua ação na aceleração do trocador na retirada do cálcio pode explicar a menor expressão da SERCA2 quando associado à Melatonina, pela ação conjunta de drogas com mecanismos diferentes e possivelmente complementares.

ABSTRACT Background: Intracellular calcium overload is known to be a precipitating factor of pancreatic cell injury in acute pancreatitis (AP). Intracellular calcium homeostasis depends of Plasmatic Membrane Calcium ATPase (PMCA), Sarcoplasmic Endothelial Reticulum Calcium ATPase 2 (SERCA 2) and the Sodium Calcium Exchanger (NCX1). The antioxidant melatonin (Mel) and Trisulfate Disaccharide (TD) that accelerates NCX1 action could reduce the cell damage determined by the AP. Aim: To evaluate m-RNA expressions of SERCA2 and NCX1 in acute pancreatitis induced by sodium taurocholate in Wistar rats pre-treated with melatonin and/or TD. Methods: Wistar rats were divided in groups: 1) without AP; 2) AP without pre-treatment; 3) AP and Melatonin; 4) AP and TD; 5) AP and Melatonin associated to TD. Pancreatic tissue samples were collected for detection of SERCA2 and NCX1 m-R NA levels by polymerase chain reaction (PCR). Results: Increased m-RNA expression of SERCA2 in the melatonin treated group, without increase of m-RNA expression of the NCX1. The TD did not affect levels of SERCA2 and NCX1 m-RNA expressions. The combined melatonin and TD treatment reduced the m-RNA expression of SERCA2. Conclusions: The effect of melatonin is restricted to increased m-RNA expression of SERCA2. Although TD does not affect gene expression, its action in accelerating calcium exchanger function can explain the slightest expression of SERCA2 m-RNA when associated with Melatonin, perhaps by a joint action of drugs with different and but possibly complementary mechanisms.