IMPACT OF THE COVID-19 PANDEMIC ON THE EMERGENCY SURGICAL TREATMENT OF COLORECTAL CANCER.

BACKGROUND: Colorectal cancer (CRC) is the most common malignancy of the gastrointestinal tract and the third most common type of cancer worldwide. The COVID-19 pandemic, during the years 2020 and 2022, increased the difficulties in offering adequate early diagnosis and treatment to CRC patients worldwide. During this period, it was only possible to treat patients who evolved with complications, mainly intestinal obstruction and perforation. AIMS: To assess the impact of the COVID-19 pandemic on the treatment of patients with CRC. METHODS: A review of data from a total of 112 patients undergoing emergency surgical treatment due to complications of CRC was carried out. Of these, 78 patients underwent emergency surgery during the COVID-19 pandemic (2020/2021), and 34 were treated before the pandemic (2018/2019). Ethnic aspects, clinical symptoms, laboratory tests, histopathological variables, intra and postoperative complications, and 90-day postoperative follow-up were compared between the two groups. RESULTS: Between the years 2018 and 2019, 79.4% (27/34) of patients had intestinal obstruction, while 20.6% (7/34) had intestinal perforation. During the period of the COVID-19 pandemic (2020/2021), 1.3% (1/78) of patients underwent surgery due to gastrointestinal bleeding, 6.4% (5/78) due to intestinal perforation, and 92.3% (72/78) due to intestinal obstruction. No statistically significant differences were recorded between the two groups in ethnic aspects, laboratory tests, type of complications, number of lymph nodes resected, compromised lymph nodes, TNM staging, pre or intraoperative complications, length of stay, readmission, or mortality rate. When considering postoperative tumor staging, among patients operated on in 2018/2019, 44.1% were classified as stage III and 38.2% as stage IV, while during the pandemic period, 28.2% presented stage III and 51.3% stage IV, also without a statistically significant difference between the two periods. Patients operated on during the pandemic had higher rates of vascular, lymphatic and perineural invasion. CONCLUSIONS: The COVID-19 pandemic increased the rate of complications related to CRC when comparing patients treated before and during the pandemic. Furthermore, it had a negative impact on histopathological variables, causing worse oncological prognoses in patients undergoing emergency surgery.

Mucin levels in glands of the colonic mucosa of rats with diversion colitis subjected to enemas containing sucralfate and n-acetylcysteine alone or in combination.

PURPOSE: To evaluate the tissue content of neutral and acidic mucins, sulfomucins and sialomucins in colonic glands devoid of intestinal transit after enemas containing sucralfate and n-acetylcysteine alone or in combination. METHODS: Sixty-four rats underwent intestinal transit bypass. A colonic segment was collected to compose the white group (without intervention). After derivation, the animals were divided into two groups according to whether enemas were performed daily for two or four weeks. Each group was subdivided into four subgroups according to the substance used: control group: saline 0.9%; sucralfate group (SCF): SCF 2 g/kg/day; n-acetylcysteine group (NAC): NAC 100 mg/kg/day; and SCF+NAC group: SCF 2 g/kg/day + NAC 100 mg/kg/day.Neutral and acidic mucins were stained by periodic acid-Schiff and alcian-blue techniques, respectively. The distinction between sulfomucins and sialomucin was made by the high alcian-blue iron diamine technique. The content of mucins in the colonic glands was measured by computerized morphometry. The inflammatory score was assessed using a validated scale. The results between the groups were compared by the Mann-Whitney's test, while the variation according to time by the Kruskal-Wallis' test (Dunn's post-test). A significance level of 5% was adopted. RESULTS: There was reduction in the inflammatory score regardless of the application of isolated or associated substances. Intervention with SCF+NAC increased the content of all mucin subtypes regardless of intervention time. CONCLUSIONS: The application of SCF+NAC reduced the inflammatory process of the colonic mucosa and increased the content of different types of mucins in the colonic glands of segments excluded from fecal transit.

Dipotassium Glycyrrhizininate Improves Skin Wound Healing by Modulating Inflammatory Process.

Wound healing is characterized by a systemic and complex process of cellular and molecular activities. Dipotassium Glycyrrhizinate (DPG), a side product derived from glycyrrhizic acid, has several biological effects, such as being antiallergic, antioxidant, antibacterial, antiviral, gastroprotective, antitumoral, and anti-inflammatory. This study aimed to evaluate the anti-inflammatory effect of topical DPG on the healing of cutaneous wounds by secondary intention in an in vivo experimental model. Twenty-four male Wistar rats were used in the experiment, and were randomly divided into six groups of four. Circular excisions were performed and topically treated for 14 days after wound induction. Macroscopic and histopathological analyses were performed. Gene expression was evaluated by real-time qPCR. Our results showed that treatment with DPG caused a decrease in the inflammatory exudate as well as an absence of active hyperemia. Increases in granulation tissue, tissue reepithelization, and total collagen were also observed. Furthermore, DPG treatment reduced the expression of pro-inflammatory cytokines (Tnf-α, Cox-2, Il-8, Irak-2, Nf-kB, and Il-1) while increasing the expression of Il-10, demonstrating anti-inflammatory effects across all three treatment periods. Based on our results, we conclude that DPG attenuates the inflammatory process by promoting skin wound healing through the modulation of distinct mechanisms and signaling pathways, including anti-inflammatory ones. This involves modulation of the expression of pro- and anti-inflammatory cytokine expression; promotion of new granulation tissue; angiogenesis; and tissue re-epithelialization, all of which contribute to tissue remodeling.

Impact of the covid-19 pandemic on the emergency surgical treatment of colorectal cancer / Impacto da pandemia da covid-19 no tratamento cirúrgico emergencial do câncer colorretal

ABSTRACT BACKGROUND: Colorectal cancer (CRC) is the most common malignancy of the gastrointestinal tract and the third most common type of cancer worldwide. The COVID-19 pandemic, during the years 2020 and 2022, increased the difficulties in offering adequate early diagnosis and treatment to CRC patients worldwide. During this period, it was only possible to treat patients who evolved with complications, mainly intestinal obstruction and perforation. AIMS: To assess the impact of the COVID-19 pandemic on the treatment of patients with CRC. METHODS: A review of data from a total of 112 patients undergoing emergency surgical treatment due to complications of CRC was carried out. Of these, 78 patients underwent emergency surgery during the COVID-19 pandemic (2020/2021), and 34 were treated before the pandemic (2018/2019). Ethnic aspects, clinical symptoms, laboratory tests, histopathological variables, intra and postoperative complications, and 90-day postoperative follow-up were compared between the two groups. RESULTS: Between the years 2018 and 2019, 79.4% (27/34) of patients had intestinal obstruction, while 20.6% (7/34) had intestinal perforation. During the period of the COVID-19 pandemic (2020/2021), 1.3% (1/78) of patients underwent surgery due to gastrointestinal bleeding, 6.4% (5/78) due to intestinal perforation, and 92.3% (72/78) due to intestinal obstruction. No statistically significant differences were recorded between the two groups in ethnic aspects, laboratory tests, type of complications, number of lymph nodes resected, compromised lymph nodes, TNM staging, pre or intraoperative complications, length of stay, readmission, or mortality rate. When considering postoperative tumor staging, among patients operated on in 2018/2019, 44.1% were classified as stage III and 38.2% as stage IV, while during the pandemic period, 28.2% presented stage III and 51.3% stage IV, also without a statistically significant difference between the two periods. Patients operated on during the pandemic had higher rates of vascular, lymphatic and perineural invasion. CONCLUSIONS: The COVID-19 pandemic increased the rate of complications related to CRC when comparing patients treated before and during the pandemic. Furthermore, it had a negative impact on histopathological variables, causing worse oncological prognoses in patients undergoing emergency surgery.

RESUMO RACIONAL: O câncer colorretal (CCR) é a doença maligna mais comum do trato gastrointestinal sendo o terceiro tipo de câncer mais comum em todo o mundo. A pandemia de COVID-19 durante os anos de 2020 e 2022 aumentou as dificuldades em se oferecer diagnóstico e tratamento precoce adequado aos pacientes com CCR em todo o mundo. Nesse período, só foi possível tratar os pacientes que evoluíram com complicações representadas, principalmente, pela obstrução e perfuração intestinal. OBJETIVOS: Avaliar o impacto da pandemia de COVID-19 no tratamento de pacientes com CCR. MÉTODOS: Foi realizada uma revisão dos dados de um total de 112 pacientes submetidos ao tratamento cirúrgico de urgência devido complicações do CCR. Destes, 78 pacientes foram submetidos a cirurgia de emergência durante o período da pandemia de COVID-19 (2020/2021), e 34 pacientes foram operados no período anterior à pandemia (2018/2019). Aspectos étnicos, sintomas clínicos, exames laboratoriais, variáveis histopatológicas, complicações intra e pós-operatórias e acompanhamento pós-operatório de 90 dias foram analisados comparando os dois grupos. RESULTADOS: Entre os anos 2018 e 2019, 79,4% (27/34) dos pacientes apresentaram obstrução intestinal enquanto 20,6% (7/34) perfuração intestinal. Durante o período da pandemia de COVID-19 (2020/2021) 1,3% (1/78) dos pacientes foram operados por hemorragia digestiva baixa, 6,4% (5/78) por perfuração intestinal e 92,3% (72/78) por obstrução intestinal. Não foram registradas diferenças estatisticamente significativas entre os dois grupos nos aspectos étnicos, exames laboratoriais, tipo de complicações, número de linfonodos ressecados, linfonodos comprometidos, estadiamento TNM, complicações pré ou intraoperatórias, tempo de internação, readmissão e taxa de mortalidade. Ao considerar o estadiamento tumoral pós-operatório, entre os pacientes operados em 2018/19, 44,1% foram classificados como estágio III e 38,2% como estágio IV, enquanto no período pandêmico, 28,2% apresentaram estágio III e 51,3% estágio IV, também sem diferença estatisticamente significativa entre os dois períodos. Doentes operados durante a pandemia apresentaram maiores índices de invasão vascular, linfática e perineural. CONCLUSÕES: A pandemia de COVID-19 aumentou as taxas de complicações relacionadas ao CCR, comparando pacientes tratados antes e durante a pandemia. Além disso, teve impacto negativo nas variáveis histopatológicas, causando piores prognósticos oncológicos em pacientes submetidos a cirurgias de emergência.

Mucin levels in glands of the colonic mucosa of rats with diversion colitis subjected to enemas containing sucralfate and n-acetylcysteine alone or in combination

ABSTRACT Purpose: To evaluate the tissue content of neutral and acidic mucins, sulfomucins and sialomucins in colonic glands devoid of intestinal transit after enemas containing sucralfate and n-acetylcysteine alone or in combination. Methods: Sixty-four rats underwent intestinal transit bypass. A colonic segment was collected to compose the white group (without intervention). After derivation, the animals were divided into two groups according to whether enemas were performed daily for two or four weeks. Each group was subdivided into four subgroups according to the substance used: control group: saline 0.9%; sucralfate group (SCF): SCF 2 g/kg/day; n-acetylcysteine group (NAC): NAC 100 mg/kg/day; and SCF+NAC group: SCF 2 g/kg/day + NAC 100 mg/kg/day.Neutral and acidic mucins were stained by periodic acid-Schiff and alcian-blue techniques, respectively. The distinction between sulfomucins and sialomucin was made by the high alcian-blue iron diamine technique. The content of mucins in the colonic glands was measured by computerized morphometry. The inflammatory score was assessed using a validated scale. The results between the groups were compared by the Mann-Whitney's test, while the variation according to time by the Kruskal-Wallis' test (Dunn's post-test). A significance level of 5% was adopted. Results: There was reduction in the inflammatory score regardless of the application of isolated or associated substances. Intervention with SCF+NAC increased the content of all mucin subtypes regardless of intervention time. Conclusions: The application of SCF+NAC reduced the inflammatory process of the colonic mucosa and increased the content of different types of mucins in the colonic glands of segments excluded from fecal transit.

A fusion protein comprising pneumococcal surface protein A and a pneumolysin derivate confers protection in a murine model of pneumococcal pneumonia.

PspA and pneumolysin are two important vaccine candidates, able to elicit protection in different models of pneumococcal infection. The high immunogenic potential of PspA, combined with a possible adjuvant effect of pneumolysin derivatives (due to their ability to interact with TLR-4) could greatly improve the immunogenicity and coverage of a protein-based pneumococcal vaccine. A chimeric protein including the N-terminal region of PspA in fusion with the pneumolysin derivative, PlD1, has been shown to induce high antibody levels against each protein, and protect mice against invasive challenge. The aim of the present study was to investigate the cellular response induced by such vaccine, and to evaluate protection in a murine model of lobar pneumococcal pneumonia. Pneumococcal pneumonia was induced in BALB/c mice by nasal instillation of a high dose of a serotype 14 strain with low virulence. Airway inflammation was confirmed by total and differential cell counts in BAL and by histological analysis of the lungs, and bacterial loads were measured 7 days after challenge. Cytokine levels were determined in the bronchoalveolar fluid (BALF) of mice immunized with rPspA-PlD1 fusion after challenge, by flow cytometry and ELISA. After challenge, the mice developed lung inflammation with no invasion of other sites, as demonstrated by histological analysis. We detected significant production of TNF-α and IL-6 in the BALF, which correlated with protection against pneumonia in the group immunized with rPspA-PlD1. In conclusion, we found that the rPspA-PlD1fusion is protective against pneumococcal pneumonia in mice, and protection is correlated with an early and controlled local inflammatory response. These results are in agreement with previous data demonstrating the efficacy of the fusion protein against pneumococcal sepsis and reinforce the potential of the rPspA-PlD1 protein chimera as a promising vaccine strategy to prevent pneumococcal disease.

Antitumor effect of isoquercetin on tissue vasohibin expression and colon cancer vasculature.

Tumor cells trigger angiogenesis through the expression of angiogenic factors. Vasohibins (VASHs) are a family of peptides that regulate angiogenesis. Flavonoids have antiproliferative antitumor properties; however, few studies have highlighted their antiangiogenic potential. This study evaluated the flavonoid isoquercetin (Q3G) as an antitumor compound related to colon cancer vascularization and regulation of VASH1 and 2. Mice bearing xenogeneic colon cancer (n = 15) were divided into 3 groups: Q3G-treated (gavage, daily over a week), bevacizumab-treated (intraperitoneal, single dose), or untreated animals. Tumor growth, histological characteristics, blood vessel volume, and VASH1 and 2 expressions were analyzed. Q3G impaired tumor growth and vascularization, upregulated VASH1, and downregulated VASH2 in comparison to untreated animals. Mice treated with Q3G showed approximately 65% fewer blood vessels than untreated animals and 50% fewer blood vessels than mice treated with bevacizumab. Thus, we show that Q3G has antitumor activity, impairs vascularization, and differentially modulates VASH1 and 2 expressions in colon cancer.

CAN SUCRALFATE ENEMA PREVENT COLITIS IN COLONIC SEGMENTS WITHOUT FECAL TRANSIT? / ENEMA DE SULCRALFATO PODE PREVENIR COLITE EM SEGMENTOS COLÔNICOS SEM TRÂNSITO FECAL?

AIM: Oxidative stress is one of the main mechanisms associated with the rupture of the defense mechanisms of the colonic epithelial barrier; it reduces the tissue content of the claudin-3 and occludin proteins, which are the main constituents of intercellular tight junctions. Sucralfate (SCF) has antioxidant activity and has been used to treat different forms of colitis. This study aimed to measure the tissue claudin-3 and occludin content of the colon mucosa without fecal transit, subjected to intervention with SCF. METHODS: Thirty-six rats were subjected to left colon colostomy and distal mucous fistula. They were divided into two groups according to euthanasia that was performed 2 or 4 weeks after the intervention. Each group was divided into three subgroups according to the enema applied daily: saline alone, SCF at 1 g/kg/day, or SCF at 2 g/kg/day. Colitis was diagnosed by the histological analysis adopting the previous validate scale. The tissue expression of both proteins was identified by immunohistochemical technique. The content of proteins was quantified by computer-assisted image analysis. RESULTS: The inflammatory score was high in colonic segments without fecal transit, and enemas with SCF reduced the inflammatory score in these segments, mainly in those animals submitted to intervention with SCF in greater concentration and for a longer period of intervention. There was an increase in tissue content of claudin-3 and occludin, related to SCF concentration. The tissue content of both proteins was not related to the intervention time. CONCLUSION: Enemas with SCF reduced the inflammation and increased the tissue content of claudin-3 and occludin in colonic mucosa without fecal stream.

OBJETIVO: O estresse oxidativo é um dos principais mecanismos associados à ruptura dos mecanismos de defesa que formam a barreira epitelial cólica e reduz o conteúdo tecidual das proteínas claudina-3 e ocludina principais constituintes das junções de oclusão intercelulares. O sucralfato, possui atividade antioxidante e tem sido usado para tratar diferentes formas de colite. Mensurar o conteúdo tecidual de claudina-3 e ocludina da mucosa do cólon sem trânsito fecal, submetido à intervenção com sucralfato. MÉTODO: Trinta e seis ratos foram submetidos à colostomia do cólon esquerdo e fístula mucosa distal. Os animais foram divididos em dois grupos de acordo com a eutanásia ser realizada duas ou quatro semanas após a intervenção. Cada grupo foi dividido em três subgrupos de acordo com o tipo de intervenção realizada diariamente: solução salina isolada; sucralfato a 1 g/kg/dia ou sucralfato a 2g/kg/dia. A colite foi diagnosticada por análise histológica adotando escala de validação prévia. A expressão tecidual de ambas as proteínas foi identificada por imunoistoquímica. O conteúdo das proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: O escore inflamatório foi maior nos segmentos cólicos sem trânsito fecal e os enemas com sucralfato reduziram o escore inflamatório nesses segmentos, principalmente nos animais submetidos à intervenção com sucralfato em maior concentração e por período mais longo de intervenção. Houve aumento no conteúdo tecidual das proteínas claudina-3 e ocludina, relacionado com a concentração de sucralfato. O conteúdo tecidual de ambas as proteínas não se modificou com a duração da intervenção. CONCLUSÃO: Enemas com sucralfato reduzem a inflamação e aumentam o conteúdo tecidual de claudina-3 e ocludina na mucosa cólica sem trânsito intestinal.

EXPRESSION OF E-CADHERIN AND CLAUDIN-3 IN THE COLONIC EPITHELIUM AFTER THE INFLIXIMAB THERAPY: EXPERIMENTAL MODEL OF DISUSE COLITIS. / EXPRESSÃO DE E-CADERINA E CLAUDINA-3 NO EPITÉLIO CÓLICO APÓS TERAPIA COM INFLIXIMABE: MODELO EXPERIMENTAL DE COLITE DE EXCLUSÃO.

AIM: The etiopathogenesis of disuse colitis (DC) has not yet been fully elucidated. The main theories consider that the disease may be related to an increase in anaerobic bacteria, the lack of short-chain fatty acid (SCFA) supply, and immunological disorders that develop in the colorectal segments devoid of fecal transit. The aim of this study was to verify whether the application of infliximab modifies the tissue content of E-cadherin and claudin-3 proteins in colonic epithelium of rats devoid of intestinal transit. METHODS: A total of 22 rats underwent intestinal transit bypass using Hartmann's procedure. They remained with the shunt for 12 weeks to allow the development of DC. Later, they were divided into three experimental groups: six animals received 2.0 mL saline solution/week, eight received infliximab at a dose of 5 mg/kg/week, and eight received infliximab at a dose of 10 mg/kg/week for 5 consecutive weeks. At the end of this period, the animals were euthanized, and the colonic segments with and without intestinal transit were removed. DC was diagnosed based on the histological changes defined by a previously validated scale. The tissue expression of E-cadherin and claudin-3 was assessed by immunohistochemistry, and the tissue content of both proteins was quantified by computer-aided image analysis. RESULTS: The colonic segments excluded from fecal transit showed a higher degree of inflammation than those exposed to fecal transit. The degree of inflammation was lower in animals treated with infliximab, regardless of the dose used. The levels of E-cadherin and claudin-3 were reduced in the excluded colon. Treating animals with infliximab increased the levels of both proteins in the colonic segments without intestinal transit, especially in animals receiving a dose of 10 mg/kg/week. CONCLUSION: Infliximab therapy reduces inflammation in the colonic segments excluded from intestinal transit and increases the tissue content of E-cadherin and claudin-3 proteins, especially when used at a concentration of 10 mg/kg/week.

OBJETIVO: A etiopatogenia da colite por desuso (DC) ainda não foi totalmente elucidada. As principais teorias consideram que a doença pode estar relacionada ao aumento de bactérias anaeróbias, falta de suprimento de ácidos graxos de cadeia curta (AGCC) e distúrbios imunológicos que se desenvolvem em segmentos colorretais desprovidos de trânsito fecal. Verificar se a aplicação de infliximabe modifica o conteúdo tecidual das proteínas E-caderina e claudina-3 no epitélio cólico de ratos sem trânsito intestinal. MÉTODOS: Vinte dois ratos foram submetidos a derivação do trânsito intestinal pelo procedimento de Hartmann. Eles permaneceram com o ostoma por 12 semanas para permitir o desenvolvimento da colite de exclusão. Em seguida, foram divididos em três grupos experimentais: seis animais receberam 2,0 ml de solução salina/semana, oito infliximabe na dose de 5 mg/Kg/semana e, os demais, infliximabe na dose de 10 mg/Kg/semana por 5 semanas consecutivas. Em seguida, os animais foram eutanasiados e os segmentos cólicos com e sem trânsito intestinal foram removidos. A colite por desuso foi diagnosticada pelas alterações histológicas definidas por uma escala previamente validada. Expressão tecidual de E-caderina e claudina-3 foi avaliada por imuno-histoquímica, e o conteúdo tecidual de ambas as proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: Segmentos cólicos exclusos de trânsito fecal apresentaram maior grau de inflamação do que os expostos ao trânsito fecal. Inflamação foi menor nos animais tratados com infliximabe, independente da dose utilizada. Níveis de E-caderina e claudina-3 estavam reduzidos no cólon excluso. O tratamento com infliximabe aumentou os níveis das proteínas em segmentos do cólon sem trânsito intestinal, principalmente nos animais que receberam a dose de 10mg/kg/semana. CONCLUSÃO: Infliximabe reduz inflamação nos segmentos do cólon excluso e aumenta o conteúdo tecidual de E-caderina e claudina-3, especialmente na concentração de 10mg/kg/semana.

A fusion protein comprising pneumococcal surface protein A and a pneumolysin derivate confers protection in a murine model of pneumococcal pneumonia

PspA and pneumolysin are two important vaccine candidates, able to elicit protection in different models of pneumococcal infection. The high immunogenic potential of PspA, combined with a possible adjuvant effect of pneumolysin derivatives (due to their ability to interact with TLR-4) could greatly improve the immunogenicity and coverage of a proteinbased pneumococcal vaccine. A chimeric protein including the N-terminal region of PspA in fusion with the pneumolysin derivative, PlD1, has been shown to induce high antibody levels against each protein, and protect mice against invasive challenge. The aim of the present study was to investigate the cellular response induced by such vaccine, and to evaluate protection in a murine model of lobar pneumococcal pneumonia. Pneumococcal pneumonia was induced in BALB/c mice by nasal instillation of a high dose of a serotype 14 strain with low virulence. Airway inflammation was confirmed by total and differential cell counts in BAL and by histological analysis of the lungs, and bacterial loads were measured 7 days after challenge. Cytokine levels were determined in the bronchoalveolar fluid (BALF) of mice immunized with rPspA-PlD1 fusion after challenge, by flow cytometry and ELISA. After challenge, the mice developed lung inflammation with no invasion of other sites, as demonstrated by histological analysis. We detected significant production of TNF-α and IL-6 in the BALF, which correlated with protection against pneumonia in the group immunized with rPspA-PlD1. In conclusion, we found that the rPspA-PlD1fusion is protective against pneumococcal pneumonia in mice, and protection is correlated with an early and controlled local inflammatory response. These results are in agreement with previous data demonstrating the efficacy of the fusion protein against pneumococcal sepsis and reinforce the potential of the rPspA-PlD1 protein chimera as a promising vaccine strategy to prevent pneumococcal disease.

Sucralfate enemas reduce the oxidative tissue damage and preserves the contents of E-cadherin and ?-catenin in colonic mucosa without fecal stream.

PURPOSE: To evaluate the effects of sucralfate enemas in tissue contents of E-cadherin and ?-catenin in an experimental diversion colitis. METHODS: Thirty-six male Wistar rats were submitted to a proximal colostomy and a distal mucous fistula. They were allocated into three groups: first group received daily saline enemas (2 mL/day) and the two other groups daily enemas with sucralfate at dosage of 1 or 2 g/kg/day, respectively. Six animals of each group were euthanized after two weeks and six animals after four weeks. The inflammation of the excluded mucosa was evaluated by histological analysis. The oxidative damage was quantified by measurement of malondialdehyde tissue levels. The expression of E-cadherin and ?-catenin was identified by immunohistochemistry, and its contents were quantified by computer-assisted image analysis. RESULTS: Sucralfate enemas reduced inflammation in animals subjected to treatment with 2 g/kg/day by four weeks, and the levels of oxidative damage in mucosa without fecal stream irrespective of concentration and time of intervention. E-cadherin and ?-catenin content increased in segments without fecal stream in those animals subjected to treatment with sucralfate. CONCLUSIONS: Sucralfate reduces the inflammation and oxidative stress and increases the tissue content of E-cadherin and ?-catenin in colonic mucosa devoid to the fecal stream.

Tissue content of metalloproteinase-9 and collagen in the colon with and without fecal stream after intervention with infliximab in rats subjected to Hartmann's surgery.

PURPOSE: Quantify the tissue content of metalloproteinase-9 (MMP-9) and collagen in colic mucosa with and without intestinal transit after infliximab administration in rats subjected to Hartmann's surgery. METHODS: Twenty-two rats underwent colon diversion by Hartmann's surgery. Animals were maintained with intestinal bypass for 12 weeks to induce development of diversion colitis (DC). Afterwards, animals were divided into three groups: first group received subcutaneous application of saline solution (SS) 0.9%, while the remaining two groups received infliximab subcutaneously at doses of 5 or 10 mg·kg-1·week-1 for five consecutive weeks. After the intervention, animals were sacrificed, removing the segments with and without intestinal transit. Diversion colitis was diagnosed by histological study, and its intensity was determined by a validated inflammatory scale. Tissue expression of MMP-9 was assessed byimmunohistochemistry, while total collagen was assessed by histochemistry. Tissue content of both was measuredby computerized morphometry. RESULTS: Colon segments without intestinal transit had a higher degree of inflammation, which improved in animals treated with infliximab. Collagen content was always lower in those without intestinal transit. There was an increase in the collagen content in the colon without transit in animals treated with infliximab, primarily at a dose of 10 mg·kg-1·week-1. There was an increase in the content of MMP-9 in the colon without fecal transit, and a reduction was observed in animals treated with infliximab, regardless of the dose used. CONCLUSIONS: Application of infliximab reduces inflammation, increases the total collagen content and decreases the content of MMP-9 in the colon without intestinal transit.

Photobiomodulation therapy increases collagen II after tendon experimental injury.

A tendon is a mechanosensitive tissue that transmits muscle-derived forces to bones. Photobiomodulation (PBM), also known as low-level laser therapy (LLLT), has been used in therapeutic approaches in tendon lesions, but uncertainties regarding its mechanisms of action have prevented its widespread use. We investigated the response of PBM therapy in experimental lesions of the Achilles tendon in rats. Thirty adult male Wistar rats weighing 250 to 300 g were surgically submitted to bilateral partial transverse section of the Achilles tendon. The right tendon was treated with PBM, whereas the left tendon served as a control. On the third postoperative day, the rats were divided into three experimental groups consisting of ten rats each, which were treated with PBM (Konf, Aculas - HB 750), 780 nm and 80 mW for 20 seconds, three times/week for 7, 14 and 28 days. The rats were sacrificed at the end of the therapeutic time period. The Sca-1 was examined by immunohistochemistry and histomorphometry, and COLA1, COLA2 and COLA3 gene expression was examined by qRT-PCR. COLA2 gene expression was higher in PBM treated tendons than in the control group. The histomorphometric analysis coincided with increased number of mesenchymal cells, characterized by Sca-1 expression in the lesion region (p<0.001). PBM effectively interferes in tendon tissue repair after injury by stimulating mesenchymal cell proliferation and the synthesis of collagen type II, which is suggested to provide structural support to the interstitial tissues during the healing process of the Achilles tendon. Further studies are needed to confirm the role of PBM in tendon healing.

Sucralfate enemas reduce the oxidative tissue damage and preserves the contents of E-cadherin and Β-catenin in colonic mucosa without fecal stream

ABSTRACT Purpose: To evaluate the effects of sucralfate enemas in tissue contents of E-cadherin and ?-catenin in an experimental diversion colitis. Methods: Thirty-six male Wistar rats were submitted to a proximal colostomy and a distal mucous fistula. They were allocated into three groups: first group received daily saline enemas (2 mL/day) and the two other groups daily enemas with sucralfate at dosage of 1 or 2 g/kg/day, respectively. Six animals of each group were euthanized after two weeks and six animals after four weeks. The inflammation of the excluded mucosa was evaluated by histological analysis. The oxidative damage was quantified by measurement of malondialdehyde tissue levels. The expression of E-cadherin and ?-catenin was identified by immunohistochemistry, and its contents were quantified by computer-assisted image analysis. Results: Sucralfate enemas reduced inflammation in animals subjected to treatment with 2 g/kg/day by four weeks, and the levels of oxidative damage in mucosa without fecal stream irrespective of concentration and time of intervention. E-cadherin and ?-catenin content increased in segments without fecal stream in those animals subjected to treatment with sucralfate. Conclusions: Sucralfate reduces the inflammation and oxidative stress and increases the tissue content of E-cadherin and ?-catenin in colonic mucosa devoid to the fecal stream.

Enema de sulcralfato pode prevenir colite em segmentos colônicos sem trânsito fecal? / Can sucralfate enema prevent colitis in colonic segments without fecal transit?

RESUMO - RACIONAL: O estresse oxidativo é um dos principais mecanismos associados à ruptura dos mecanismos de defesa que formam a barreira epitelial cólica e reduz o conteúdo tecidual das proteínas claudina-3 e ocludina principais constituintes das junções de oclusão intercelulares. O sucralfato, possui atividade antioxidante e tem sido usado para tratar diferentes formas de colite. OBJETIVO: Mensurar o conteúdo tecidual de claudina-3 e ocludina da mucosa do cólon sem trânsito fecal, submetido à intervenção com sucralfato. MÉTODO: Trinta e seis ratos foram submetidos à colostomia do cólon esquerdo e fístula mucosa distal. Os animais foram divididos em dois grupos de acordo com a eutanásia ser realizada duas ou quatro semanas após a intervenção. Cada grupo foi dividido em três subgrupos de acordo com o tipo de intervenção realizada diariamente: solução salina isolada; sucralfato a 1 g/kg/dia ou sucralfato a 2g/kg/dia. A colite foi diagnosticada por análise histológica adotando escala de validação prévia. A expressão tecidual de ambas as proteínas foi identificada por imunoistoquímica. O conteúdo das proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: O escore inflamatório foi maior nos segmentos cólicos sem trânsito fecal e os enemas com sucralfato reduziram o escore inflamatório nesses segmentos, principalmente nos animais submetidos à intervenção com sucralfato em maior concentração e por período mais longo de intervenção. Houve aumento no conteúdo tecidual das proteínas claudina-3 e ocludina, relacionado com a concentração de sucralfato. O conteúdo tecidual de ambas as proteínas não se modificou com a duração da intervenção. CONCLUSÃO: Enemas com sucralfato reduzem a inflamação e aumentam o conteúdo tecidual de claudina-3 e ocludina na mucosa cólica sem trânsito intestinal.

ABSTRACT - BACKGROUND: Oxidative stress is one of the main mechanisms associated with the rupture of the defense mechanisms of the colonic epithelial barrier; it reduces the tissue content of the claudin-3 and occludin proteins, which are the main constituents of intercellular tight junctions. Sucralfate (SCF) has antioxidant activity and has been used to treat different forms of colitis. AIM: This study aimed to measure the tissue claudin-3 and occludin content of the colon mucosa without fecal transit, subjected to intervention with SCF. METHODS: Thirty-six rats were subjected to left colon colostomy and distal mucous fistula. They were divided into two groups according to euthanasia that was performed 2 or 4 weeks after the intervention. Each group was divided into three subgroups according to the enema applied daily: saline alone, SCF at 1 g/kg/day, or SCF at 2 g/kg/day. Colitis was diagnosed by the histological analysis adopting the previous validate scale. The tissue expression of both proteins was identified by immunohistochemical technique. The content of proteins was quantified by computer-assisted image analysis. RESULTS: The inflammatory score was high in colonic segments without fecal transit, and enemas with SCF reduced the inflammatory score in these segments, mainly in those animals submitted to intervention with SCF in greater concentration and for a longer period of intervention. There was an increase in tissue content of claudin-3 and occludin, related to SCF concentration. The tissue content of both proteins was not related to the intervention time. CONCLUSION: Enemas with SCF reduced the inflammation and increased the tissue content of claudin-3 and occludin in colonic mucosa without fecal stream.

Expressão de e-caderina e claudina-3 no epitélio cólico após terapia com infliximabe: modelo experimental de colite de exclusão / Expression of e-cadherin and claudin-3 in the colonic epithelium after the infliximab therapy: experimental model of disuse colitis

RESUMO - RACIONAL: A etiopatogenia da colite por desuso (DC) ainda não foi totalmente elucidada. As principais teorias consideram que a doença pode estar relacionada ao aumento de bactérias anaeróbias, falta de suprimento de ácidos graxos de cadeia curta (AGCC) e distúrbios imunológicos que se desenvolvem em segmentos colorretais desprovidos de trânsito fecal. OBJETIVO: Verificar se a aplicação de infliximabe modifica o conteúdo tecidual das proteínas E-caderina e claudina-3 no epitélio cólico de ratos sem trânsito intestinal. MÉTODOS: Vinte dois ratos foram submetidos a derivação do trânsito intestinal pelo procedimento de Hartmann. Eles permaneceram com o ostoma por 12 semanas para permitir o desenvolvimento da colite de exclusão. Em seguida, foram divididos em três grupos experimentais: seis animais receberam 2,0 ml de solução salina/semana, oito infliximabe na dose de 5 mg/Kg/semana e, os demais, infliximabe na dose de 10 mg/Kg/semana por 5 semanas consecutivas. Em seguida, os animais foram eutanasiados e os segmentos cólicos com e sem trânsito intestinal foram removidos. A colite por desuso foi diagnosticada pelas alterações histológicas definidas por uma escala previamente validada. Expressão tecidual de E-caderina e claudina-3 foi avaliada por imuno-histoquímica, e o conteúdo tecidual de ambas as proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: Segmentos cólicos exclusos de trânsito fecal apresentaram maior grau de inflamação do que os expostos ao trânsito fecal. Inflamação foi menor nos animais tratados com infliximabe, independente da dose utilizada. Níveis de E-caderina e claudina-3 estavam reduzidos no cólon excluso. O tratamento com infliximabe aumentou os níveis das proteínas em segmentos do cólon sem trânsito intestinal, principalmente nos animais que receberam a dose de 10mg/kg/semana. CONCLUSÃO: Infliximabe reduz inflamação nos segmentos do cólon excluso e aumenta o conteúdo tecidual de E-caderina e claudina-3, especialmente na concentração de 10mg/kg/semana.

ABSTRACT - BACKGROUND: The etiopathogenesis of disuse colitis (DC) has not yet been fully elucidated. The main theories consider that the disease may be related to an increase in anaerobic bacteria, the lack of short-chain fatty acid (SCFA) supply, and immunological disorders that develop in the colorectal segments devoid of fecal transit. AIM: The aim of this study was to verify whether the application of infliximab modifies the tissue content of E-cadherin and claudin-3 proteins in colonic epithelium of rats devoid of intestinal transit. METHODS: A total of 22 rats underwent intestinal transit bypass using Hartmann's procedure. They remained with the shunt for 12 weeks to allow the development of DC. Later, they were divided into three experimental groups: six animals received 2.0 mL saline solution/week, eight received infliximab at a dose of 5 mg/kg/week, and eight received infliximab at a dose of 10 mg/kg/week for 5 consecutive weeks. At the end of this period, the animals were euthanized, and the colonic segments with and without intestinal transit were removed. DC was diagnosed based on the histological changes defined by a previously validated scale. The tissue expression of E-cadherin and claudin-3 was assessed by immunohistochemistry, and the tissue content of both proteins was quantified by computer-aided image analysis. RESULTS: The colonic segments excluded from fecal transit showed a higher degree of inflammation than those exposed to fecal transit. The degree of inflammation was lower in animals treated with infliximab, regardless of the dose used. The levels of E-cadherin and claudin-3 were reduced in the excluded colon. Treating animals with infliximab increased the levels of both proteins in the colonic segments without intestinal transit, especially in animals receiving a dose of 10 mg/kg/week. CONCLUSION: Infliximab therapy reduces inflammation in the colonic segments excluded from intestinal transit and increases the tissue content of E-cadherin and claudin-3 proteins, especially when used at a concentration of 10 mg/kg/week.

Extra virgin olive oil and flaxseed oil have no preventive effects on DSS-induced acute ulcerative colitis.

OBJECTIVES: The aim of this study was to evaluate the preventive effects of extra virgin olive oil (EVOO) or flaxseed oil (FO) on dextran sodium sulfate (DSS)-induced acute ulcerative colitis in female mice. METHODS: Eighty C57BL/6J mice of 8-weeks-old were divided in four groups: Control (SO), 10%EVOO, 10%FO and 5%EVOO+5%FO. The oils were given through the AIN-93M diet. After 30 days, animals were divided in four more groups, in which half received 3%DSS in water for 5 days. Body weight loss, bleeding and stool consistency were verified for the Disease Activity Index (DAI). Animals were euthanized and their colon and spleen weighted and measured. Histopathological analysis, the concentrations of TNF-α, IL-1ß, and IL-10 and the iNOS expression were evaluated in the colon samples. RESULTS: Animals that received DSS presented with elevated disease activity index values; increased colon weight-to-length ratio; augmented leukocyte infiltration into the lamina propria and submucosa; and increased production of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6, and greater inducible nitric oxide synthase expression in the distal colon. Individually or in combination, the oils were not able to reverse or mitigate any of the DSS-induced symptoms or damage. Additionally, the group of animals treated with DSS and supplemented with FO displayed increased spleen weight-to-body weight ratio, and the group that received a combination of EVOO and FO presented increased TNF-α levels compared with the respective control group. CONCLUSION: Consumption of large amounts of EVOO and FO as a treatment for or prevention against ulcerative colitis could potentially elicit unwanted adverse effects.

Functional Insights From KpfR, a New Transcriptional Regulator of Fimbrial Expression That Is Crucial for Klebsiella pneumoniae Pathogenicity.

Although originally known as an opportunistic pathogen, Klebsiella pneumoniae has been considered a worldwide health threat nowadays due to the emergence of hypervirulent and antibiotic-resistant strains capable of causing severe infections not only on immunocompromised patients but also on healthy individuals. Fimbriae is an essential virulence factor for K. pneumoniae, especially in urinary tract infections (UTIs), because it allows the pathogen to adhere and invade urothelial cells and to form biofilms on biotic and abiotic surfaces. The importance of fimbriae for K. pneumoniae pathogenicity is highlighted by the large number of fimbrial gene clusters on the bacterium genome, which requires a coordinated and finely adjusted system to control the synthesis of these structures. In this work, we describe KpfR as a new transcriptional repressor of fimbrial expression in K. pneumoniae and discuss its role in the bacterium pathogenicity. K. pneumoniae with disrupted kpfR gene exhibited a hyperfimbriated phenotype with enhanced biofilm formation and greater adhesion to and replication within epithelial host cells. Nonetheless, the mutant strain was attenuated for colonization of the bladder in a murine model of urinary tract infection. These results indicate that KpfR is an important transcriptional repressor that, by negatively controlling the expression of fimbriae, prevents K. pneumoniae from having a hyperfimbriated phenotype and from being recognized and eliminated by the host immune system.