Histopathological diagnosis of colon cancer using micro-FTIR hyperspectral imaging and deep learning.

BACKGROUND AND OBJECTIVE: Current studies based on digital biopsy images have achieved satisfactory results in detecting colon cancer despite their limited visual spectral range. Such methods may be less accurate when applied to samples taken from the tumor margin region or to samples containing multiple diagnoses. In contrast with the traditional computer vision approach, micro-FTIR hyperspectral images quantify the tissue-light interaction on a histochemical level and characterize different tissue pathologies, as they present a unique spectral signature. Therefore, this paper investigates the possibility of using hyperspectral images acquired over micro-FTIR absorbance spectroscopy to characterize healthy, inflammatory, and tumor colon tissues. METHODS: The proposed method consists of modeling hyperspectral data into a voxel format to detect the patterns of each voxel using fully connected deep neural network. A web-based computer-aided diagnosis tool for inference is also provided. RESULTS: Our experiments were performed using the K-fold cross-validation protocol in an intrapatient approach and achieved an overall accuracy of 99% using a deep neural network and 96% using a linear support vector machine. Through the experiments, we noticed the high performance of the method in characterizing such tissues using deep learning and hyperspectral images, indicating that the infrared spectrum contains relevant information and can be used to assist pathologists during the diagnostic process.

Mast cell-T cell axis alters development of colitis-dependent and colitis-independent colorectal tumours: potential for therapeutically targeting via mast cell inhibition.

BACKGROUND: Colorectal cancer (CRC) has a high mortality rate and can develop in either colitis-dependent (colitis-associated (CA)-CRC) or colitis-independent (sporadic (s)CRC) manner. There has been a significant debate about whether mast cells (MCs) promote or inhibit the development of CRC. Herein we investigated MC activity throughout the multistepped development of CRC in both human patients and animal models. METHODS: We analyzed human patient matched samples of healthy colon vs CRC tissue alongside conducting a The Cancer Genome Atlas-based immunogenomic analysis and multiple experiments employing genetically engineered mouse (GEM) models. RESULTS: Analyzing human CRC samples revealed that MCs can be active or inactive in this disease. An activated MC population decreased the number of tumor-residing CD8 T cells. In mice, MC deficiency decreased the development of CA-CRC lesions, while it increased the density of tumor-based CD8 infiltration. Furthermore, co-culture experiments revealed that tumor-primed MCs promote apoptosis in CRC cells. In MC-deficient mice, we found that MCs inhibited the development of sCRC lesions. Further exploration of this with several GEM models confirmed that different immune responses alter and are altered by MC activity, which directly alters colon tumorigenesis. Since rescuing MC activity with bone marrow transplantation in MC-deficient mice or pharmacologically inhibiting MC effects impacts the development of sCRC lesions, we explored its therapeutic potential against CRC. MC activity promoted CRC cell engraftment by inhibiting CD8+ cell infiltration in tumors, pharmacologically blocking it inhibits the ability of allograft tumors to develop. This therapeutic strategy potentiated the cytotoxic activity of fluorouracil chemotherapy. CONCLUSION: Therefore, we suggest that MCs have a dual role throughout CRC development and are potential druggable targets against this disease.

Experimental Model of Rectal Carcinogenesis Induced by N-Methyl-N-Nitrosoguanidine in Mice with Endoscopic Evaluation.

Background and purpose: The discovery of chemical substances with carcinogenic properties has allowed the development of several experimental models of colorectal cancer (CRC). Classically, experimental models of CRC in mice have been evaluated through clinical or serial euthanasia. The present study aims to investigate the role of low endoscopy in the analysis of carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Methods: Thirty C57BL6 mice were divided into two groups: a control group with fifteen animals that underwent rectal instillation of saline solution on day 0 and a carcinogen group with fifteen animals that underwent a 100 mg/kg MNNG rectal instillation on day 0. In both groups, low endoscopies were performed on weeks 4 and 8. We used a validated endoscopic scoring system to evaluate the severity of colitis and colorectal tumor. Euthanasia was carried out at week 12. Results: We observed higher inflammation scores (p <0.001) and a higher number of tumors (p <0.05) in the MNNG group than the control group, both at weeks 4 and 8. A worsening of inflammation scores from the first to the second endoscopy was also noticeable in the MNNG group. There were no bowel perforations related to the procedure, and there was one death in the control group. Conclusion: Low endoscopy in experimental animals allows safe macroscopic evaluation of colorectal carcinogenesis without the need for euthanasia.

Thalidomide Reduces Cell Proliferation in Endometriosis Experimentally Induced in Rats.

OBJECTIVE: To analyze the effect of thalidomide on the progression of endometriotic lesions experimentally induced in rats and to characterize the pattern of cell proliferation by immunohistochemical Proliferating Cell Nuclear Antigen (PCNA) labeling of eutopic and ectopic endometrium. METHODS: Fifteen female Wistar rats underwent laparotomy for endometriosis induction by resection of one uterine horn, isolation of the endometrium and fixation of a tissue segment to the pelvic peritoneum. Four weeks after, the animals were divided into 3 groups: control (I), 10mg/kg/day (II) and 1mg/kg/day (III) intraperitoneal thalidomide for 10 days. The lesion was excised together with the opposite uterine horn for endometrial gland and stroma analysis. Eutopic and ectopic endometrial tissue was submitted to immunohistochemistry for analysis of cell proliferation by PCNA labeling and the cell proliferation index (CPI) was calculated as the number of labeled cells per 1,000 cells. RESULTS: Group I showed a mean CPI of 0.248 ± 0.0513 in the gland and of 0.178 ± 0.046 in the stroma. In contrast, Groups II and III showed a significantly lower CPI, that is, 0.088 ± 0.009 and 0.080 ± 0.021 for the gland (p < 0.001) and 0.0945 ± 0.0066 and 0.075 ± 0.018 for the stroma (p < 0.001), respectively. Also, the mean lesion area of Group I was 69.2 mm2, a significantly higher value compared with Group II (49.4 mm2, p = 0.023) and Group III (48.6 mm2, p = 0.006). No significant difference was observed between Groups II and III. CONCLUSION: Thalidomide proved to be effective in reducing the lesion area and CPI of the experimental endometriosis implants both at the dose of 1 mg/kg/day and at the dose of 10 mg/kg/day.

OBJETIVO: Analisar o efeito da talidomida na progressão de lesões endometrióticas induzidas experimentalmente em ratas e caracterizar o padrão de proliferação celular pela marcação imunohistoquímica de Antígeno Nuclear de Célula Proliferativa (PCNA) no endométrio eutópico e ectópico. MéTODOS: Quinze ratas Wistar foram submetidas a laparotomia para indução de endometriose por ressecção de um corno uterino, isolamento do endométrio e fixação de um segmento do tecido ao peritônio pélvico. Após quatro semanas, os animais foram divididos em 3 grupos: controle (I), 10 mg/kg/dia (II) e 1 mg/kg/dia (III) de talidomida intraperitoneal por um período de 10 dias. As lesões foram resseccionadas juntamente com o corno uterino oposto para análise da glândula endometrial e do estroma. O tecido endometrial eutópico e ectópico foi submetido à imunohistoquímica para análise da proliferação celular por marcação com PCNA e o índice de proliferação celular (CPI) foi calculado como o número de células marcadas por 1.000 células. RESULTADOS: O grupo I apresentou média de CPI de 0,248 ± 0,0513 na glândula e de 0,178 ± 0,046 no estroma. Em contraste, os grupos II e III apresentaram CPI significativamente menor, isto é, 0,088 ± 0,009 e 0,080 ± 0,021 para a glândula (p < 0,001) e 0,0945 ± 0,0066 e 0,075 ± 0,018 para o estroma (p < 0,001), respectivamente. Além disso, a área de lesão média do Grupo I foi de 69,2 mm2, valor significativamente maior em relação ao Grupo II (49,4 mm2, p = 0,023) e Grupo III (48,6 mm2, p = 0,006). Não houve diferença estatisticamente significante entre os Grupos II e III. CONCLUSãO: A talidomida mostrou-se eficaz na redução da área da lesão e CPI dos implantes de endometriose experimental tanto na dose de 1 mg/kg/dia quanto na dose de 10 mg/kg/dia.

Thalidomide reduces cell proliferation in endometriosis experimentally induced in rats / A talidomida induz diminuição da proliferação celular em endometriose experimentalmente induzida em ratas

Abstract Objective To analyze the effect of thalidomide on the progression of endometriotic lesions experimentally induced in rats and to characterize the pattern of cell proliferation by immunohistochemical Proliferating Cell Nuclear Antigen (PCNA) labeling of eutopic and ectopic endometrium. Methods Fifteen female Wistar rats underwent laparotomy for endometriosis induction by resection of one uterine horn, isolation of the endometrium and fixation of a tissue segment to the pelvic peritoneum. Four weeks after, the animals were divided into 3 groups: control (I), 10mg/kg/day (II) and 1mg/kg/day (III) intraperitoneal thalidomide for 10 days. The lesion was excised together with the opposite uterine horn for endometrial gland and stroma analysis. Eutopic and ectopic endometrial tissue was submitted to immunohistochemistry for analysis of cell proliferation by PCNA labeling and the cell proliferation index (CPI) was calculated as the number of labeled cells per 1,000 cells. Results Group I showed a mean CPI of 0.248 ± 0.0513 in the gland and of 0.178 ± 0.046 in the stroma. In contrast, Groups II and III showed a significantly lower CPI, that is, 0.088 ± 0.009 and 0.080 ± 0.021 for the gland (p < 0.001) and 0.0945 ± 0.0066 and 0.075 ± 0.018 for the stroma (p < 0.001), respectively. Also, the mean lesion area of Group I was 69.2mm2, a significantly higher value compared with Group II (49.4mm2, p = 0.023) and Group III (48.6mm2, p = 0.006). No significant difference was observed between Groups II and III. Conclusion Thalidomide proved to be effective in reducing the lesion area and CPI of the experimental endometriosis implants both at the dose of 1mg/kg/day and at the dose of 10 mg/kg/day.

Resumo Objetivo Analisar o efeito da talidomida na progressão de lesões endometrióticas induzidas experimentalmente em ratas e caracterizar o padrão de proliferação celular pela marcação imunohistoquímica de Antígeno Nuclear de Célula Proliferativa (PCNA) no endométrio eutópico e ectópico. Métodos Quinze ratas Wistar foram submetidas a laparotomia para indução de endometriose por ressecção de um corno uterino, isolamento do endométrio e fixação de um segmento do tecido ao peritônio pélvico. Após quatro semanas, os animais foram divididos em 3 grupos: controle (I), 10 mg/kg/dia (II) e 1 mg/kg/dia (III) de talidomida intraperitoneal por um período de 10 dias. As lesões foram resseccionadas juntamente com o corno uterino oposto para análise da glândula endometrial e do estroma. O tecido endometrial eutópico e ectópico foi submetido à imunohistoquímica para análise da proliferação celular por marcação com PCNA e o índice de proliferação celular (CPI) foi calculado como o número de células marcadas por 1.000 células. Resultados O grupo I apresentou média de CPI de 0,248 ± 0,0513 na glândula e de 0,178 ± 0,046 no estroma. Em contraste, os grupos II e III apresentaram CPI significativamentemenor, isto é, 0,088 ± 0,009 e 0,080 ± 0,021 para a glândula (p < 0,001) e 0,0945 ± 0,0066 e 0,075 ± 0,018 para o estroma (p < 0,001), respectivamente. Além disso, a área de lesãomédia do Grupo I foi de 69,2mm2, valor significativamentemaior em relação ao Grupo II (49,4mm2, p = 0,023) e Grupo III (48,6mm2, p = 0,006). Não houve diferença estatisticamente significante entre os Grupos II e III. Conclusão A talidomida mostrou-se eficaz na redução da área da lesão e CPI dos implantes de endometriose experimental tanto na dose de 1mg/kg/dia quanto na dose de 10 mg/kg/dia.

Botulinum toxin as a treatment for short bowel syndrome in rats.

PURPOSE: The denervation of the intestine with benzalkonium chloride (BAC) reduces mortality and improves weight gain in rats with short bowel syndrome (SBS). Nevertheless, translating these promising findings from bench to bedside is not feasible because BAC promotes peritonitis and irreversible denervation which may be followed by an uncontrolled dilatation of the viscera. The use of botulinum toxin (BT) instead of BAC to achieve the denervation of the remaining small intestine in SBS could be an interesting option because it leads to a mild and transient denervation of the intestine. METHODS: Here we evaluated the effects of the ileal denervation with BT in rats with SBS by verifying the body weight variation and intestinal morphological parameters. Four groups with 6 animals each were submitted to enterectomy with an ileal injection of saline (group E) or BT (group EBT). Control groups were submitted to simulated surgery with an ileal injection of BT (group BT) or saline (group C - control). RESULTS: We observed that the treatment of the remaining ileum with BT completely reversed the weight loss associated to extensive small bowel resection. CONCLUSION: This may provide a new promising approach to the surgical treatment of SBS.

Effect of High Voltage Pulsed Current on the integration of total skin grafts in rats submitted to nicotine action.

OBJECTIVE: The aim of this study was to evaluate the impact of High Voltage Pulsed Current (HVPC) on the integration of total skin grafts in rats submitted to nicotine action. MATERIALS AND METHODS: For this purpose, 60 adult Wistar rats randomly distributed in 6 groups of 10 animals were analyzed. The electrical stimulation (anodic and cathodic stimulation, motor level, 30 min at 10 Hz; minimum voltage 20 µs and 100 µs pulse interval) was applied for seven days, starting on the third day after surgery and after the dressing was removed from the graft. RESULTS: Anodic HVPC promoted greater graft integration, demonstrating a lower percentage of tissue contraction, a lower number of inflammatory infiltrates and a greater amount of vascular endothelial growth factor (VEGF), as well as a higher number of newly formed blood vessels. CONCLUSIONS: HVPC can positively influence the integration of skin grafts in nicotine-treated rats. anodic HVPC is shown to promote greater integration in relation to a lower percentage of tissue contraction, a lower number of inflammatory infiltrates and a greater amount of vascular endothelial growth factor and newformed blood vessels. Whereas, the cathodic polarity has presented smaller amount of tissue gap.

Myenteric Denervation of the Gut with Benzalkonium Chloride: A Review of Forty Years of an Experimental Model.

Experimental denervation of organs plays a key role in understanding the functional aspects of the normal innervation as well as the diseases related to them. In 1978 the experimental model of myenteric denervation of the rat gut by serosal application of benzalkonium chloride (BAC) was proposed. BAC is a positively charged surface-active alkylamine and is a powerful cationic detergent, which destroys bacteria after ionic attraction and for this reason is largely used as a surgical antiseptic. Since its initial report, the BAC-induced myenteric denervation model has been used to study many functional and pathological aspects of the enteric nervous system. So far this is the only pure method of myenteric denervation available for research in this area. Promising reports in the literature have shed light on the possibilities for the development of new uses of the BAC-denervation experimental model as a therapeutic tool in some pathological situations. This review aims to shed light on the main historical and recent findings provided by this experimental model.

Coffee, but Neither Decaffeinated Coffee nor Caffeine, Elicits Chemoprotection Against a Direct Carcinogen in the Colon of Wistar Rats.

Colorectal cancer (CRC) is the third most frequent malignancy worldwide. Coffee is the second most consumed drink in the globe and suggested to decrease the CRC risk. Here, we explored whether coffee, decaffeinated coffee, or caffeine impact on the development of colorectal carcinogenesis induced by the direct carcinogen N-methyl-N-nitro-N-nitrosoguanidine (MNNG) in rats. To this end, sixty-four young male Wistar rats were divided into eight groups of eight animals each. We analyzed the frequency of dysplastic crypts and expression of metallothionein as a biomarker of the cancer risk, as well the expression of phosphorylated H2A histone family/member X (γH2AX) for DNA damage and cyclooxygenase-2 (COX-2) for inflammatory response. We also studied the oxidative stress profile in hepatic and colonic frozen samples (malondialdehyde [MDA], glutathione [GSH], and α-tocopherol). We found that coffee but neither decaffeinated coffee nor caffeine decreased the development of dysplastic crypts in MNNG-exposed rats. All treatments reduced DNA damage intensity in colonocytes. Only decaffeinated coffee increased the numbers of metallothionein positive crypts in comparison with coffee-treated rats. Coffee and caffeine inhibited COX-2 expression in the colon. Both decaffeinated coffee and caffeine decreased hepatic α-tocopherol levels. We suggest that coffee may have other compounds that elicit greater chemoprotective effects than caffeine reducing the CRC risk.

Botulinum toxin as a treatment for short bowel syndrome in rats

Abstract Purpose: The denervation of the intestine with benzalkonium chloride (BAC) reduces mortality and improves weight gain in rats with short bowel syndrome (SBS). Nevertheless, translating these promising findings from bench to bedside is not feasible because BAC promotes peritonitis and irreversible denervation which may be followed by an uncontrolled dilatation of the viscera. The use of botulinum toxin (BT) instead of BAC to achieve the denervation of the remaining small intestine in SBS could be an interesting option because it leads to a mild and transient denervation of the intestine. Methods: Here we evaluated the effects of the ileal denervation with BT in rats with SBS by verifying the body weight variation and intestinal morphological parameters. Four groups with 6 animals each were submitted to enterectomy with an ileal injection of saline (group E) or BT (group EBT). Control groups were submitted to simulated surgery with an ileal injection of BT (group BT) or saline (group C - control). Results: We observed that the treatment of the remaining ileum with BT completely reversed the weight loss associated to extensive small bowel resection. Conclusion: This may provide a new promising approach to the surgical treatment of SBS.

Increased Expression Levels of Metalloprotease, Tissue Inhibitor of Metalloprotease, Metallothionein, and p63 in Ectopic Endometrium: An Animal Experimental Study.

OBJECTIVE: To characterize the patterns of cell differentiation, proliferation, and tissue invasion in eutopic and ectopic endometrium of rabbits with induced endometriotic lesions via a well- known experimental model, 4 and 8 weeks after the endometrial implantation procedure. METHODS: Twenty-nine female New Zealand rabbits underwent laparotomy for endometriosis induction through the resection of one uterine horn, isolation of the endometrium, and fixation of tissue segment to the pelvic peritoneum. Two groups of animals (one with 14 animals, and the other with15) were sacrificed 4 and 8 weeks after endometriosis induction. The lesion was excised along with the opposite uterine horn for endometrial gland and stroma determination. Immunohistochemical reactions were performed in eutopic and ectopic endometrial tissues for analysis of the following markers: metalloprotease (MMP-9) and tissue inhibitor of metalloprotease (TIMP-2), which are involved in the invasive capacity of the endometrial tissue; and metallothionein (MT) and p63, which are involved in cell differentiation and proliferation. RESULTS: The intensity of the immunostaining for MMP9, TIMP-2, MT, and p63 was higher in ectopic endometria than in eutopic endometria. However, when the ectopic lesions were compared at 4 and 8 weeks, no significant difference was observed, with the exception of the marker p63, which was more evident after 8 weeks of evolution of the ectopic endometrial tissue. CONCLUSION: Ectopic endometrial lesions seem to express greater power for cell differentiation and tissue invasion, compared with eutopic endometria, demonstrating a potentially invasive, progressive, and heterogeneous presentation of endometriosis.

OBJETIVO: Caracterizar o padrão de diferenciação celular, proliferação e invasão tecidual em endométrio eutópico e ectópico de coelhas com lesões de endometriose induzidas por um modelo experimental 4 e 8 semanas após o procedimento de implantação endometrial. MéTODOS: Vinte e nove coelhas fêmeas Nova Zelândia foram submetidas a laparotomia para indução de endometriose através da ressecção de um dos cornos uterinos, isolamento do endométrio e fixação do tecido no peritônio pélvico. Dois grupos de animais (14 animais em um grupo e 15 animais no outro) foram sacrificados 4 e 8 semanas após a indução da endometriose. A lesão foi excisada junto com o corno uterino contralateral para determinação da presença de glândulas e de estroma endometrial. Reações de imunohistoquímica foram realizadas no tecido endometrial eutópico e ectópico para análise dos seguintes marcadores: metaloprotease (MMP9) e inibidor tecidual da metaloprotease 2 (TIMP-2), os quais estão envolvidos na capacidade de invasão do tecido endometrial; e metalotioneina (MT) e p63, os quais estão envolvidos na diferenciação e proliferação celular. RESULTADOS: A intensidade da imunomarcação para MMP9, TIMP-2, MT e p63 foi mais alta nos endométrios ectópicos do que nos endométrios eutópicos. Contudo, quando as lesões foram comparadas entre 4 e 8 semanas, nenhuma diferença foi observada, com exceção do marcador p63, o qual foi mais evidente depois de 8 semanas de evolução do tecido endometrial ectópico. CONCLUSãO: Lesões endometriais ectópicas parecem expressar maior poder de diferenciação celular e de invasão tecidual comparadas com endométrios eutópicos, demonstrando o potencial de invasão, de progressão e de apresentação heterogênea da endometriose.

Increased expression levels of metalloprotease, tissue inhibitor of metalloprotease, metallothionein, and p63 in ectopic endometrium: an animal experimental study / Aumento nos níveis de expressão de metaloprotease, inibidor tecidual das metaloproteases, metalotioneina e p63 em endométrio ectópico: um estudo experimental animal

Abstract Objective To characterize the patterns of cell differentiation, proliferation, and tissue invasion in eutopic and ectopic endometrium of rabbits with induced endometriotic lesions via a well- known experimental model, 4 and 8 weeks after the endometrial implantation procedure. Methods Twenty-nine female New Zealand rabbits underwent laparotomy for endometriosis induction through the resection of one uterine horn, isolation of the endometrium, and fixation of tissue segment to the pelvic peritoneum. Two groups of animals (one with 14 animals, and the other with15) were sacrificed 4 and 8 weeks after endometriosis induction. The lesion was excised along with the opposite uterine horn for endometrial gland and stroma determination. Immunohistochemical reactions were performed in eutopic and ectopic endometrial tissues for analysis of the following markers: metalloprotease (MMP-9) and tissue inhibitor of metalloprotease (TIMP-2), which are involved in the invasive capacity of the endometrial tissue; and metallothionein (MT) and p63, which are involved in cell differentiation and proliferation. Results The intensity of the immunostaining for MMP9, TIMP-2, MT, and p63 was higher in ectopic endometria than in eutopic endometria. However, when the ectopic lesions were compared at 4 and 8 weeks, no significant difference was observed, with the exception of the marker p63, which was more evident after 8 weeks of evolution of the ectopic endometrial tissue. Conclusion Ectopic endometrial lesions seem to express greater power for cell differentiation and tissue invasion, compared with eutopic endometria, demonstrating a potentially invasive, progressive, and heterogeneous presentation of endometriosis.

Resumo Objetivo Caracterizar o padrão de diferenciação celular, proliferação e invasão tecidual em endométrio eutópico e ectópico de coelhas com lesões de endometriose induzidas por um modelo experimental 4 e 8 semanas após o procedimento de implantação endometrial. Métodos Vinte e nove coelhas fêmeas Nova Zelândia foram submetidas a laparotomia para indução de endometriose através da ressecção de um dos cornos uterinos, isolamento do endométrio e fixação do tecido no peritônio pélvico. Dois grupos de animais (14 animais em um grupo e 15 animais no outro) foram sacrificados 4 e 8 semanas após a indução da endometriose. A lesão foi excisada junto com o corno uterino contralateral para determinação da presença de glândulas e de estroma endometrial. Reações de imunohistoquímica foram realizadas no tecido endometrial eutópico e ectópico para análise dos seguintes marcadores: metaloprotease (MMP9) e inibidor tecidual da metaloprotease 2 (TIMP-2), os quais estão envolvidos na capacidade de invasão do tecido endometrial; e metalotioneina (MT) e p63, os quais estão envolvidos na diferenciação e proliferação celular. Resultados A intensidade da imunomarcação para MMP9, TIMP-2, MT e p63 foi mais alta nos endométrios ectópicos do que nos endométrios eutópicos. Contudo, quando as lesões foram comparadas entre 4 e 8 semanas, nenhuma diferença foi observada, com exceção do marcador p63, o qual foi mais evidente depois de 8 semanas de evolução do tecido endometrial ectópico. Conclusão Lesões endometriais ectópicas parecem expressar maior poder de diferenciação celular e de invasão tecidual comparadas com endométrios eutópicos, demonstrando o potencial de invasão, de progressão e de apresentação heterogênea da endometriose.

Increased exposure to pesticides and colon cancer: Early evidence in Brazil.

Environmental factors may increase colon cancer (CC) risk. It has been suggested that pesticides could play a significant role in the etiology of this malignancy. As agriculture is one of the mainstays of the Brazilian economy, this country has become the largest pesticides consumer worldwide. The CC burden is also increasing in Brazil. Herein, we examined data from the Brazilian Federal Government to determine whether CC mortality and pesticide consumption may be associated. Database of the Ministry of Health provided CC mortality data in Brazil, while pesticide usage was accessed at the website of Brazilian Institute of Environment and Renewable Natural Resources. The CC mortality in the Brazilian states was calculated as standard mortality rates (SMR). All Bayesian analysis was performed using a Markov chain Monte Carlo method in WinBUGS software. We observed that CC mortality has exhibited a steady increase for more than a decade, which correlated with the amount of sold pesticides in the country. Both observations are concentrated in the Southern and the Southeast regions of Brazil. Although ecological studies like ours have methodological limitations, the current dataset suggests the possibility that pesticide exposure may be a risk factor for CC. It warrants further investigation.

Rankings, avaliações e recursos escassos: o que fazer com a medicina e a odontologia legal? / Rankings, scientific assessments and resources: what to do with Forensic Medicine and Dentistry?

O uso de rankings para mensuração de desempenho de universidades se tornou algo frequente e com ampla divulgação no meio acadêmico. A CWRU - Center for World University Rankings ­ tornou-se um dos mais conhecidos e anualmente divulga a escala de colocação de universidades de todo o mundo, inclusive por áreas de conhecimento. O ranking referente a 2016 colocou a Universidade de São Paulo (USP) como a melhor universidade na América Latina, sendo a área de Odontologia (cirurgia oral e medicina bucal) como a 1ª colocada e a Medicina Legal em 10º. A proposta deste artigo é analisar criticamente as colocações das áreas anteriormente mencionadas neste ranking e o contraste com o recém anunciado corte de verbas para pesquisa anunciado pelo governo federal no Brasil. Além disso, propõe colocar em discussão, em um enfoque bioético, como forma de avaliação de qualidade de produção científica, a análise do custo financeiro de um trabalho publicado versus seu fator de impacto, ou seja, levar em conta a relação custo/benefício de um trabalho científico. Essa seria uma forma de tornar mais justa e equitativa a avaliação comparativa entre pesquisadores que trabalham com grandes apoios financeiros frente àqueles que trabalham com poucos recursos em relação ao impacto de suas publicações.

The use of rankings to measure university performance has become frequent and widespread in the academic world. The CWRU - Center for World University Rankings - has become one of the most well-known and annually publishes the scale of placement of universities around the world, including by areas of expertise. The ranking for 2016 ranked the University of São Paulo (USP) as the best university in Latin America. The area of Dentistry (oral surgery and oral medicine) was ranked 1st and Legal Medicine ranked 10th. The proposal of this article is to critically analyze the placements of the previously mentioned areas in this ranking and the contrast with the recently announced cut of research funds announced by the federal government in Brazil. In addition, in some bioethics focus, to discuss the analysis of the financial costs of a published work versus its impact factor, as a way of evaluating the quality of scientific production, to allow a more fair and equitable comparative evaluation between researchers working with large financial supports when facing those who work with reduced funding and the respective impact of their publications.

Chemopreventive effects of a Tamarindus indica fruit extract against colon carcinogenesis depends on the dietary cholesterol levels in hamsters.

Tamarind has significant antioxidant potential. We showed that tamarind protects hypercholesterolemic hamsters from atherosclerosis. Hypercholesterolemia might increase the risk of colon cancer. We investigated whether tamarind extract modulates the risk of colon cancer in hypercholesterolemic hamsters. Hamsters (n = 64) were given tamarind and a hypercholesterolemic diet for 8 weeks. The groups were the control, tamarind treatment, hypercholesterolemic, and hypercholesterolemic treated with tamarind groups. Half of each group was exposed to the carcinogen dimethylhydrazine (DMH) at the 8th week. All hamsters were euthanatized at the 10th week. In carcinogen-exposed hypercholesterolemic hamsters, tamarind did not alter the cholesterol or triglyceride serum levels, but it reduced biomarkers of liver damage (alanine transaminase [ALT], and aspartate aminotransferase [AST]). Tamarind decreased DNA damage in hepatocytes, as demonstrated by analysis with an anti-γH2A.X antibody. In liver and serum samples, we found that this fruit extract reduced lipid peroxidation (thiobarbituric acid reactive substances [TBARS]) and increased endogenous antioxidant mechanisms (glutathione peroxidase [GPx] and superoxide dismutase [SOD]). However, tamarind did not alter either lipid peroxidation or antioxidant defenses in the colon, which contrasts with DMH exposure. Moreover, tamarind significantly increased the stool content of cholesterol. Although tamarind reduced the risk of colon cancer in hypercholesterolemic hamsters that were carcinogenically exposed to DMH by 63.8% (Metallothionein), it was still ∼51% higher than for animals fed a regular diet. Staining colon samples with an anti-γH2A.X antibody confirmed these findings. We suggest that tamarind has chemoprotective activity against the development of colon carcinogenesis, although a hypercholesterolemic diet might impair this protection.

Jacalin Has Chemopreventive Effects on Colon Cancer Development.

Colorectal cancer, which is one of the most common causes of cancer-related deaths worldwide, has a slow natural history that provides a great opportunity for prevention strategies. Plant-derived natural products have received considerable attention because of their inherent colorectal cancer chemopreventive effects. The plant lectin jacalin specifically recognizes the tumor-associated Thomsen-Friedenreich antigen and has antiproliferative effects on human colon cancer cells, highlighting its potential antitumor activity. To evaluate jacalin's potential application in colorectal cancer chemoprevention, we studied its effects on the early stages of carcinogenesis. Balb/c mice were given 4 intrarectal deposits of 0.1 ml solution of Methyl-N'-Nitro-N-Nitroso-Guanidine (5 mg/ml) twice a week (with a 3-day interval) for 2 weeks. Starting 2 weeks before carcinogen administration, animals were treated orally with jacalin (0.5 and 25 µg) three times a week (on alternate weekdays) for 10 weeks. We show that jacalin treatment reduced the number of preneoplastic lesions in carcinogen-exposed mice. This anticarcinogenic activity was associated with decreased colonic epithelial cell proliferation and stromal COX-2 expression and with increased intestinal production of TNF-α. Our results demonstrate that jacalin is able to modulate the early stages of colon carcinogenesis and emphasize its promising chemopreventive activity in colorectal cancer.

High-Fat and Fat-Enriched Diets Impair the Benefits of Moderate Physical Training in the Aorta and the Heart in Rats.

AIM: Millions of people die each year due to cardiovascular disease (CVD). A Western lifestyle not only fuses a significant intake of fat with physical inactivity and obesity but also promotes CVD. Recent evidence suggests that dietary fat intake impairs the benefits of physical training. We investigated whether aerobic training could reverse the adverse effects of a high-fat diet (HFD) on the aorta. Then, we explored whether this type of exercise could reverse the damage to the heart that is imposed by fat-enriched diet (FED). METHODS: Rats were randomly assigned to two experiments, which lasted 8 weeks each. First, rats swam for 60 min and were fed either a regular diet [standard diet (STD)] or an HFD. After aortic samples had been collected, the rats underwent a histopathological analysis for different biomarkers. Another experiment subjected rats that were fed either an STD or an FED to swimming for 20 or 90 min. RESULTS: The first experiment revealed that rats that were subjected to an HFD-endured increased oxidative damage in the aorta that exercises could not counteract. Together with increased cyclooxygenase 2 expression, an HFD in combination with physical training increased the number of macrophages. A reduction in collagen fibers with an increased number of positive α-actin cells and expression of matrix metalloproteinase-2 occurred concomitantly. Upon analyzing the second experiment, we found that physically training rats that were given an FED for 90 min/day decreased the cardiac adipose tissue density, although it did not protect the heart from fat-induced oxidative damage. Even though the physical training lowered cholesterol levels that were promoted by the FED, the levels were still higher than those in the animals that were given an STD. Feeding rats an FED impaired the swimming protocol's effects on lowering triglyceride concentration. Additionally, exercise was unable to reverse the fat-induced deregulation in hepatic antioxidant and lipid peroxidation activities. CONCLUSION: Our findings reveal that an increased intake of fat undermines the potential benefits of physical exercise on the heart and the aorta.

Photobiomodulation laser and pulsed electrical field increase the viability of the musculocutaneous flap in diabetic rats.

The purpose of this study is to investigate the effect of pulsed electrical field (PEF) and photobiomodulation laser (PBM) on the viability of the TRAM flap in diabetic rats. Fifty Wistar rats were divided into five homogeneous groups: Group 1-control; Group 2-diabetics; Group 3-diabetics + PEF; Group 4-diabetic + laser 660 nm, 10 J/cm2, 0.27 J; Group 5-diabetic + laser 660 nm, 140 J/cm2, 3.9 J. The percentage of necrotic area was evaluated using software Image J®. The peripheral circulation of the flap was evaluated by infrared thermography FLIR T450sc (FLIR® Systems-Oregon USA). The thickness of the epidermis (haematoxylin-eosin), mast cell (toluidine blue), leukocytes, vascular endothelial growth factor, fibroblast and newly formed blood vessels were evaluated. For the statistical analysis, the Kruskal-Wallis test was applied followed by Dunn and ANOVA test followed by Tukey with critical level of 5% (p < 0.05). The PEF reduced the area of necrosis, decreased the leukocytes, increased the mast cells, increased the thickness of epidermis and increased newly formed blood vessels when it was compared to the untreated diabetic group of animals. Laser 660 nm, fluence 140 J/cm2 (3.9 J) showed better results than the 10 J/cm2 (0.27 J) related to reduction of the area of necrosis and the number of leukocytes, increased mast cells, increased thickness of the epidermis, increased vascular endothelial growth factor, increased fibroblast growth factor and increase of newly formed blood vessels in diabetic animals. The laser and pulsed electrical field increase the viability of the musculocutaneous flap in diabetic rats.

Laser photobiomodulation (830 and 660 nm) in mast cells, VEGF, FGF, and CD34 of the musculocutaneous flap in rats submitted to nicotine.

The aim of this study was to investigate the effect of laser photobiomodulation (PBM) on the viability of the transverse rectus abdominis musculocutaneous (TRAM) flap in rats subjected to the action of nicotine. We evaluated 60 albino Wistar rats, divided into six groups of ten animals. Group 1 (saline) underwent the surgical technique to obtain a TRAM flap; group 2 (laser 830 nm) underwent the surgical technique and was irradiated with a laser 830 nm; group 3 (laser 660 nm) underwent the surgical technique and was irradiated with a laser 660 nm; group 4 was treated with nicotine subcutaneously (2 mg/kg/2×/day/4 weeks) and underwent surgery; group 5 (nicotine + laser 830 nm) was exposed to nicotine, underwent the surgical technique, and was irradiated with a laser 830 nm; group 6 (nicotine + laser 660 nm) was exposed to nicotine, underwent the surgical technique, and was irradiated with a laser 660 nm. The application of PBM occurred immediately after surgery and on the two following days. The percentage of necrosis was assessed using the AxioVision® software. The number of mast cells (toluidine blue staining) was evaluated, and immunohistochemistry was performed to detect vascular endothelial growth factor expression (anti-VEGF-A), fibroblasts (anti-basic FGF), and neoformed vessels (anti-CD34). PBM with a wavelength of 830 nm increased the viability of the TRAM flap, with a smaller area of necrosis, increased number of mast cells, and higher expression of VEGF and CD34. PBM increases the viability of musculocutaneous flaps treated with to nicotine.

A critical discussion on diet, genomic mutations and repair mechanisms in colon carcinogenesis.

Colon cancer is one of the most common malignancies and its etiology closely tied to dietary habits. Recent epidemiological data shows that colon cancer incidence is shifting to a much younger population. In this regard, some dietary components from a regular human meal might have various DNA-damaging compounds. Given that not every person endure cancer, the colonic malignancy develops throughout decades, and persistent DNA damage promotes cancer when induced at the proper intensity, a critical discussion of possible novel mechanisms by which carcinogens promote these tumors is urgently needed. Robust genomic sequencing analyses showed that low and late cell cycle expressed genes are prone to undergo mutation. Moreover, detection and repair mechanisms have a particular threshold to be activated throughout the G2/M phase, and reactivation of these devices during the M phase promotes genomic instability. Conditions of combined exposure to non-genotoxic concentrations of various carcinogens seem to act effectively through these weaknesses in genomic repair mechanisms. Therefore, we suggest that the natural tolerance of body defence mechanisms eventually become overwhelmed by the chronic exposure to different combinations and intensities of dietary mutagens leading to the high incidence of colon cancer in modern society.