Frequency of Human Papillomavirus Detection in Chagasic Megaesophagus Associated or Not with Esophageal Squamous Cell Carcinoma.

BACKGROUND: Chagasic megaesophagus (CM) as well as the presence of human papillomavirus (HPV) has been reported as etiological factors for esophageal squamous cell carcinoma (ESCC). OBJECTIVE: We assessed the prevalence of HPV DNA in a series of ESCCs associated or not with CM. Data obtained were further correlated to the pathological and clinical data of affected individuals. METHODS: A retrospective study was performed on 92 formalin-fixed and paraffin-embedded tissues collected from patients referred to 3 different hospitals in São Paulo, Brazil: Barretos Cancer Hospital, Barretos, São Paulo; Federal University of Triângulo Mineiro, Uberaba, Minas Gerais; and São Paulo State University, Botucatu, São Paulo. Cases were divided into 3 groups: (i) 24 patients with CM associated with ESCC (CM/ESCC); (ii) 37 patients with ESCC without CM (ESCC); and (iii) 31 patients with CM without ESCC (CM). Detection of HPV DNA was assessed in all samples by a genotyping assay combining multiplex polymerase chain reaction and bead-based Luminex technology. RESULTS: We identified a high prevalence of high-risk HPV in patients in the CM group (12/31, 38.8%) and CM/ESCC (8/24, 33.3%), compared to individuals in the ESCC group (6/37, 16.3%). The individuals in the groups with cancer (ESCC and CM/ESCC) had a higher frequency of HPV-16 (4/9, 44.5% and 2/8, 25.0%). The other types of high-risk HPVs detected were HPV-31, 45, 51, 53, 56, 66, and 73. We also observed in some samples HPV coinfection by more than one viral type. Despite the high incidence of HPV, it did not show any association with the patient's clinical-pathological and molecular (TP53 mutation status) characteristics. CONCLUSION: This is the first report of the presence of HPV DNA in CM associated with ESCC. HPV infection was more presence in megaesophagus lesions. Further studies are needed to confirm and better understand the role of persistent HPV infection in patients with CM.

Remote Pathology teaching under the COVID-19 pandemic: Medical students' perceptions.

CONTEXT: The COVID-19 pandemic has forced traditional teaching to be re-structured and delivered online. OBJECTIVE: To analyse medical students' perceptions about the benefits and difficulties of the remote teaching of Pathology during the COVID-19 pandemic. DESIGN: A cross-sectional study was performed with an online survey applied to students from the third and fourth year of medical graduation, who attended the remote teaching of Pathology during the COVID-19 pandemic. Online teaching methods consisted of synchronous activities with live interactive lectures, case-based discussions and asynchronous activities with recorded lectures, tutorials and texts available on the online teaching platform. Students' perceptions about the remote teaching of Pathology were assessed through online survey. RESULTS: Ninety students (47.4%) of 190 participants completed the questionnaire, 45 were male and 52 in the third year of medical graduation. Perceived conditions that facilitated Pathology learning included the use of the online teaching platform and time flexibility for study. Students regarded live interactive lectures as superior to traditional face-to-face lectures. Perceived conditions that hindered the implementation of the online teaching included difficulty separating study from home activities, lack of motivation and worsening of quality of life due to physical distancing from colleagues and the faculty. Overall, the remote teaching of Pathology was positively valued by 80% of the students. CONCLUSION: Online tools allowed the content of Pathology to be successfully delivered to the students during the COVID-19 pandemic. This experience may be a model for future teaching activities of Pathology in health science education.

Are biopsies always necessary in upper and lower gastrointestinal endoscopy in children? A retrospective 10-year analysis.

Little attention has been given to the efficiency and validity of performing routine endoscopic biopsies in normal areas in children. This study aimed to investigate the need to perform routine biopsies in upper gastrointestinal endoscopy (UDE) and colonoscopy in normal areas by comparing macroscopy and histology. It was a 10-year retrospective analysis with the inclusion of 761 UDEs and 177 colonoscopies. Considering all segments, UDEs showed false-positive result rates of 73.11% and false-negative result rates of 14.34%. The histological results modified the initial management in 53.95% of patients. Considering all segments, colonoscopies showed false-positive result rates of 63.64% and false-negative result rates of 30.97%. The histological results modified the initial management in 34.45% of patients.Conclusion: If biopsies were obtained only in abnormal areas, the diagnosis would be lost in 53.95% of the patients in upper endoscopies and 85.7% of the colonoscopies, which justifies routine maintenance of biopsies in macroscopically normal areas in children. What is Known: • Little attention has been given to the efficiency and validity of endoscopic biopsies of normal areas during pediatric exams. • Only a few pediatric studies have correlated macroscopic and histological findings from endoscopic biopsies, and low sensitivity and specificity, as well as poor agreement, were reported. What is New: • Our study confirms the evidence that routine biopsies from macroscopically normal areas during upper and lower digestive endoscopies can lead to histopathological diagnoses and different medical management. • This is the first research on this topic in a Latin population, from a developing country, reassuring the results obtained in previous papers from other countries.

Adjustments in ß-Adrenergic Signaling Contribute to the Amelioration of Cardiac Dysfunction by Exercise Training in Supravalvular Aortic Stenosis.

BACKGROUND/AIMS: Aortic stenosis-induced chronic pressure overload leads to cardiac dysfunction and congestive heart failure. The pathophysiological mechanisms of the myocardial impairment are multifactorial and include maladaptive ß-adrenergic signaling. Exercise training (ET) has been used as a non-pharmacological therapy for heart failure management. The present study tested the hypothesis that exercise training attenuates diastolic dysfunction through ß-adrenergic signaling preservation. METHODS: Wistar rats were submitted to ascending aortic stenosis (AS) surgery, and after 18 weeks, a moderate aerobic exercise training protocol was performed for ten weeks. RESULTS: ET attenuated diastolic dysfunction, evaluated by echocardiogram and isolated papillary muscle (IPM) assay. Also, ET reduced features of heart failure, cross-sectional cardiomyocyte area, and exercise intolerance, assessed by treadmill exercise testing. The ß2 adrenergic receptor protein expression was increased in AS rats independently of exercise. Interestingly, ET restored the protein levels of phosphorylated phospholamban at Serine 16 and preserved the ß-adrenergic receptor responsiveness as visualized by the lower myocardial compliance decline and time to 50% tension development and relaxation during ß-adrenergic stimulation in the IPM than untrained rats. Additionally, AS rats presented higher levels of TNFα and iNOS, which were attenuated by ET. CONCLUSION: Moderate ET improves exercise tolerance, reduces heart failure features, and attenuates diastolic dysfunction. In the myocardium, ET decreases the cross-sectional area of the cardiomyocyte and preserves the ß-adrenergic responsiveness, which reveals that the adjustments in ß-adrenergic signaling contribute to the amelioration of cardiac dysfunction by mild exercise training in aortic stenosis rats.

Is breath testing without 13C-labelled external urea able to detect Helicobacter pylori infection?

Helicobacter pylori (H. pylori) infection is the main cause of gastric inflammation and peptic ulcer disease. Diagnosis and treatment are important to prevent these outcomes. The diagnosis of H. pylori infection can be performed by non-invasive methods, such as 13C-urea breath test (13C-UBT). As endogenous urea is normally released to body cavities, we sought to investigate the usefulness of UBT without 13C-labelled external urea to detect H. pylori infection. The analysis was performed in a series of adult patients just before upper gastrointestinal endoscopy and biopsy to investigate dyspeptic symptoms. Breath samples were analyzed using isotope ratio mass spectrometry (IRMS). The natural variation of 13C and 18O isotopic abundance in the breath samples was also investigated. The results of the isotopic analysis were compared with the findings of the histopathological evaluation of gastric biopsies, which is the gold standard to detect H. pylori infection. No differences between patients with or without H. pylori infection could be detected by the isotope analysis of breath tests without 13C-urea. Therefore, our results showed that UBT without 13C-urea, analyzed by IRMS, was not useful to detect H. pylori infection in the study population.

Barium Enema Revisited in the Workup for the Diagnosis of Hirschsprung's Disease.

OBJECTIVE: To analyse the diagnostic capacity of barium enema (BE) in the diagnostic investigation for Hirschsprung's disease (HD) was analyzed for transition zone (TZ) identification and rectosigmoid index (RSI) ≤1.0 determination. PATIENTS AND METHODS: BE images were analyzed retrospectively by 2 examiners and the results were compared with the histopathology of rectal biopsies. RESULTS: TZ identification and RSI ≤1.0 were assessed separately and combined in 43 patients. Twelve (27.9%) patients had the diagnosis of HD based on rectal biopsies. TZ identification presented better diagnostic capacity for the 2 examiners than RSI ≤1.0. However, interexaminer agreement was higher for RSI ≤1.0 than for TZ identification. The combination of TZ identification and RSI ≤1.0 increased the sensitivity (83.3%-92.3%) and the negative predictive value (90.4%-92.3%). CONCLUSION: Therefore, the high diagnostic sensitivity of TZ identification combined to RSI ≤1.0 reinforces the usefulness of these BE parameters in the screening for Hirschsprung's disease.

Capsaicin reduces genotoxicity, colonic cell proliferation and preneoplastic lesions induced by 1,2-dimethylhydrazine in rats.

Capsaicin (8-Methyl-N-vanillyl-(trans)-6-nonenamide) is the major pungent ingredient found in chili peppers consumed worldwide. Most reports on capsaicin potential carcinogenicity have yielded inconsistent findings. Some studies have shown that capsaicin exerts anti-proliferative and pro-apoptotic effects on different cancer cell lines, while others have reported an association between capsaicin at high doses with mutagenicity and carcinogenicity. Thus, this study aimed at assessing the effects of capsaicin administration on 1,2-dimethyl-hydrazine (DMH)-induced colon carcinogenesis in male Wistar rats. Our results show that capsaicin administration, before and during carcinogen exposure, modified DMH-induced cytotoxicity and genotoxicity, promoting anti-proliferative and pro-apoptotic responses through the expression of the genes involved in apoptosis, cell cycle suppression and cell/tissue differentiation. Furthermore, capsaicin reduced aberrant crypt foci (ACF) number and multiplicity, although there were no differences in tumor incidence and multiplicity among the groups. Taken together, the results suggest that capsaicin may have a preventive effect against DMH-induced colorectal carcinogenesis.

An overview of chemically induced rodent models for sporadic colorectal cancer: Histopathological and translational perspectives.

Globally, colorectal cancer (CRC) is one of the most frequently diagnosed human gastrointestinal neoplasia and the second leading cause of cancer-related death in both men and women. Despite considerable efforts currently devoted to the study of the biology and treatment of CRC, patient prognosis and survival are still poor. Sporadic CRC is a complex multistep disease and usually emerges in the setting of lifestyle and dietary changes mainly observed in industrialized countries with high human development index (HDI) (westernized style). The molecular pathogenesis of sporadic CRC presents genetic heterogeneity with APC, RAS, PIK3CA, TGFBR, SMAD4, and TP53 mutations usually detected during the progression of this malignancy. The establishment of sporadic CRC models has become essential for both basic and translational research to improve our understanding of the pathophysiology, unravel new molecular drivers, and preventive/therapeutic improvement of this malignancy. Chemically induced rodent models of sporadic CRC recapitulate most key morphological and genetic/epigenetic events observed during the promotion and progression of this malignancy, establishing effective diagnostic and prevention strategies to be translated into clinical practice. The present review gathers the main features of the state-of-the-art evidence on chemically induced rodent models, widely applied for translational modelling of sporadic CRC with a specific focus on histopathology and prevention perspectives. Our narrative review reinforces the persistent value of these bioassays and encourages the use of multimodel strategies for further investigations.

Lack of protective effects of zinc gluconate against rat colon carcinogenesis.

Zinc has been proposed as a promising chemopreventive candidate against colon cancer. However, few studies on the potential beneficial effects of this trace element on cancer chemoprevention are available. The present study was designed to investigate the potential modifying influence of zinc gluconate (ZnGly) on the initiation step of colon carcinogenesis induced by 1,2-dimethylhydrazine (DMH). Male Wistar rats received orally ZnGly (15 mg elemental zinc/kg, 3 times per wk) 2 wk before and during DMH treatment (3 × 40 mg/kg, once a wk). The animals were euthanized at the end of 4th and 16th wk. Colons were analyzed for aberrant crypt foci (ACF) and tumor development. Blood and colon zinc levels, cell proliferation, and apoptosis indexes in colonic crypts were analyzed 24 h after the last DMH administration. Oral treatment with ZnGly did neither alter the number of ACF nor the indexes of cell proliferation and apoptosis in the colonic mucosa. The incidence and multiplicity of colon tumors induced by DMH and their histopathological patterns were not modified by previous treatment with ZnGly. These findings indicate a lack of chemopreventive action of zinc gluconate supplementation on the initiation step of rat colon carcinogenesis induced by DMH.

Effects of Ginkgo biloba on chemically-induced mammary tumors in rats receiving tamoxifen.

BACKGROUND: Ginkgo biloba extract (GbE) is used extensively by breast cancer patients undergoing treatment with Tamoxifen (TAM). Thus, the present study investigated the effects of GbE in female Sprague-Dawley (SD) rats bearing chemically-induced mammary tumors and receiving TAM. METHODS: Animals bearing mammary tumors (≥1 cm in diameter) were divided into four groups: TAM [10 mg/kg, intragastrically (i.g.)], TAM plus GbE [50 and 100 mg/kg, intraperitoneally (i.p.)] or an untreated control group. After 4 weeks, the therapeutic efficacy of the different treatments was evaluated by measuring the tumor volume (cm(3)) and the proportions of each tumor that were alive, necrotic or degenerative (mm(2)). In addition, labeling indexes (LI%) were calculated for cell proliferation (PCNA LI%) and apoptosis (cleaved caspase-3 LI%), expression of estrogen receptor-alpha (ER-α) and p63 biomarkers. RESULTS: Overall, the tumor volume and the PCNA LI% within live tumor areas were reduced by 83% and 99%, respectively, in all TAM-treated groups when compared to the untreated control group. GbE treatment (100 mg/kg) reduced the proportions of live (24.8%) and necrotic areas (2.9%) (p = 0.046 and p = 0.038, respectively) and significantly increased the proportion of degenerative areas (72.9%) (p = 0.004) in mammary tumors when compared to the group treated only with TAM. The expression of ER-α, p63 and cleaved caspase-3 in live tumor tissues was not modified by GbE treatment. CONCLUSIONS: Co-treatment with 100 mg/kg GbE presented a slightly beneficial effect on the therapeutic efficacy of TAM in female SD rats bearing mammary tumors.

A useful panel for the diagnosis of Hirschsprung disease in rectal biopsies: calretinin immunostaining and acetylcholinesterase histochesmistry.

The pathological evaluation of rectal biopsies for the diagnosis of Hirschsprung disease has been a challenging issue. We analyzed prospectively the usefulness of calretinin immunostaining and acetylcholinesterase (AChE) histochesmistry in rectal biopsies for the diagnosis of Hirschsprung disease. Frozen tissue samples from 43 patients were used for AChE histochemistry and paraffin-embedded sections for calretinin immunohistochemistry and conventional histology (hematoxylin and eosin [H&E]). Activity for AChE, was demonstrated in 13 of 43 cases, and the absence of immunoreactivity for calretinin was observed in 14 of 43 cases. Conventional histology (H&E) did not reveal ganglion cells in 24 of 43 cases. The results on calretinin were in good agreement with AChE according to the κ index (0.946; P<.001) and presented significantly higher specificity (96.7×63.3; P<.002) and accuracy (97.6×74.4; P<.003) when compared with conventional histology (H&E). The final diagnosis of Hirschsprung disease was confirmed in 13 of 43 patients who were submitted to surgical treatment. The results of the present study indicate that calretinin can be a good tool in ruling out the diagnosis of Hirschsprung disease, by showing positive staining in ganglion cells and intrinsic nerve fibers, whereas AChE is useful in confirming the diagnosis of Hirschsprung disease, by revealing activity of this enzyme in hypertrophied nerve fibers. The association between calretinin and AChE can be a useful panel for the histopathologic evaluation of rectal biopsies for the diagnosis of Hirschsprung disease.

Necrotizing amebic colitis in an elder patient: an unexpected autopsy finding.

Necrotizing amebic colitis is an uncommon amebiasis complication associated with high mortality. We present a case of necrotizing amebic colitis in an old patient whose diagnosis was revealed at postmortem examination. An 81-year-old man died at home without medical attention. The postmortem examination revealed ulcers involving the entire colon and intestinal perforation. The ulcers were large, geographic, and necrotizing, extending from the cecum to the rectum. The histological examination disclosed the infectious etiology by showing amebic trophozoites at the base of the ulcers. No extra-intestinal lesions were found. No information about previous episodes of dysentery or travel could be obtained. The potential role of aging or drug-causing immunosuppression and the evolution of chronic and latent intestinal infection to a severe and invasive form of amebiasis is discussed. This case reinforces the value of postmortem examination for diagnosing diseases not clinically identified.

Association between Clinical and Histopathological Findings in Intestinal Neuronal Dysplasia Type B: An Advance towards Its Definition as a Disease.

INTRODUCTION: Intestinal neuronal dysplasia type B (IND-B) is a controversial entity that affects the submucosal nerve plexus of the distal intestine. The lack of definition of the causal relationship between histological findings and clinical symptoms has been identified as the primary point to be elucidated in the scientific investigation related to IND-B, which is essential for it to be considered a disease. OBJECTIVE: To investigate the relationship between histopathological findings and symptoms in a series of patients with IND-B. METHODS: Twenty-seven patients with histopathological diagnosis of IND-B, according to the Frankfurt Consensus (1990), who underwent surgical treatment through colorectal resections were included. Data from medical records regarding the clinical picture of the patients at the time of diagnosis, including the intestinal symptom index (ISI) and a detailed histopathological analysis of the rectal specimens, were retrieved. Exploratory factor analysis was performed, applying the principal components method for clusters with Varimax rotation. RESULTS: Two factors were determined: the first, determined by histopathological and clinical variables, and the second, composed of the main symptoms presented in patients with IND-B, including ISI. Factorial rotation showed the association between the two factors and, through a graph, demonstrated the proximity between ISI values and histopathological alterations. CONCLUSION: There was evidence of an association between the clinical features presented by patients with IND-B and the histopathological findings of the rectal samples. These results support the understanding of IND-B as a disease.

Upper gastrointestinal histopathological findings in children and adolescents with nonulcer dyspepsia with Helicobacter pylori infection.

OBJECTIVES: The aim of the study was to investigate the histopathological lesions in the upper gastrointestinal mucosa associated with Helicobacter pylori infection in children with nonulcer dyspepsia. METHODS: A cross-sectional case-control study was performed on 185 Brazilian children and adolescents (4-17 years, mean 9.5 ±â€Š2.7 years), 63.2% girls, submitted to upper gastrointestinal endoscopy. The histopathological lesions of the esophageal and gastric mucosa were analyzed in biopsy samples. RESULTS: H pylori infection was identified in 96 children (51.8%). Moderate to severe chronic active gastritis was present in antrum (70.5%) and corpus (45.2%), with higher grading in antrum than in corpus (P < 0.05). The topographic distribution of inflammation was pangastritis (61.9%), followed by antral (32.1%) and corpus (5.9%). H pylori density was higher in antrum than in corpus. Intestinal metaplasia was not found in the H pylori-infected group, nor was significant gastric atrophy. The scores for esophagitis were significantly higher (P < 0.05) in the noninfected group (1.4 ±â€Š0.8) than in the H pylori-infected group (1.07 ±â€Š0.9), with significant negative correlation (r = 0.29; P < 0.05) with the scores of gastric inflammation. CONCLUSIONS: The prevalence of H pylori infection was high among children with dyspepsia and associated with moderate/severe degrees of gastric inflammation. The high scores of esophagitis in the noninfected group point to 2 distinct groups of pathological conditions sharing similar clinical patterns.

Prevalence of Helicobacter pylori infection among asymptomatic children in southeastern Brazil: a cross-sectional study.

BACKGROUND: The prevalence of Helico bacter pylori (H. pylori) infection is decreasing worldwide, but is still high in developing countries. We previously observed an H. pylori infection rate of 52% among children and adolescents with chronic non-ulcer dyspepsia. OBJECTIVE: To investigate the prevalence of H. pylori infection among asymptomatic children living in a single region and to evaluate the risk factors for this infection. DESIGN AND SETTING: Cross-sectional study in which 161 children aged 5-13 years (mean age 7.8 years), at a public school in Botucatu, state of São Paulo, southeastern Brazil, were assessed. METHOD: The children's H. pylori infection status was determined through the urea breath test and the risk factors for acquisition of the infection were determined based on a sociodemographic questionnaire. RESULTS: The overall prevalence of H. pylori infection was 20.5%: 18.7% among females and 22.2% among males. The results from the sociodemographic survey did not differ between children with and without H. pylori infection. 30.9% of the children had previous records of upper gastrointestinal symptoms, which consisted of H. pylori infection in only 26.5% of these cases. Family histories of gastritis and peptic ulcer disease were found in relation to 50% and 32.3% of the children with H. pylori infection respectively. CONCLUSION: The prevalence of H. pylori infection among asymptomatic children in southeastern Brazil is lower than that recorded among symptomatic children in the same region and similar to the prevalence of H. pylori infection observed in developed countries.

PTEN Immunohistochemistry.

CONTEXT.­: Intestinal neuronal dysplasia type B (IND B) is a complex entity involving the enteric nervous system, clinically manifested with constipation in infancy. Diagnosis has been established by histopathologic analysis of rectal biopsies. However, the criteria for the diagnosis have been questioned and modified, hindering diagnostic practice. OBJECTIVE.­: To analyze the applicability of PTEN immunohistochemistry in the diagnosis of IND B and to compare with control cases and cases of Hirschsprung disease (HD). DESIGN.­: PTEN immunohistochemical expression was analyzed in colorectal samples from 29 cases of IND B and compared with 4 control cases and 6 cases of HD. The pattern of PTEN immunoexpression was analyzed in glial cells of the submucosal and myenteric nerve plexuses and in neural fibrils of the muscularis propria using a scoring system. RESULTS.­: Marked reduction or absence of PTEN expression was observed in glial cells of the submucosal nerve plexuses in all cases of the IND B group and in the myenteric nerve plexuses in 28 of 29 cases (96.5%). Lack of PTEN expression was detected in neural fibrils within the muscularis propria in 21 of 29 cases (72%) of the IND B group. PTEN expression was positive in the same neural structures of the control and HD groups. CONCLUSIONS.­: PTEN immunohistochemistry may be a valuable tool in the diagnostic evaluation of IND B. Lack of or reduction of PTEN expression in neural fibrils within the muscularis propria suggests that involvement of the neuromuscular junction may be a key event in the pathogenesis of the motility disturbance occurring in IND B.

Western diet-induced mouse model of non-alcoholic fatty liver disease associated with metabolic outcomes: Features of gut microbiome-liver-adipose tissue axis.

OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) has a growing epidemiologic and economic burden. It is associated with Western diet (WD) patterns, and its pathogenesis involves metabolic disorders (obesity, dyslipidemia, hyperglycemia, and diabetes) and gut dysbiosis, features that are usually neglected or not reproduced by most animal models. Thus, we established a 6-mo WD-induced NAFLD mouse model associated with metabolic disorder, investigating its main features at the gut microbiome-liver-adipose tissue axis, also evaluating the correlations of gut dysbiosis to the other disease outcomes. METHODS: Male C57 BL6 mice received a high-fat (30% lard and 0.2% cholesterol, ∼57% calories) and sucrose-rich (20%) chow, and a high-sugar solution (23.1 and 18.9 g/L of D-fructose and D-glucose) for 6 mo. RESULTS: The model featured high serum cholesterol levels, glucose intolerance, and hyperinsulinemia. WD intervention resulted in extensive macro/microvesicular liver steatosis and pericellular fibrosis-resembling human disease-accompanied by hepatic stellate cell activation and CD68+ macrophage infiltration, increased protein levels of proinflammatory p65-nuclear factor-κB, interleukin-6 and tumor necrosis factor-α, with decreased antioxidant regulator Nrf2. Mice showed clear obesity with adipocyte hypertrophy, and CD68+macrophage/mast cell infiltration in adipose tissue while a reduction in number of goblet cells was also observed in the small intestine. Moreover, the pyrosequencing of the 16 S ribosomal RNA of gut cecal content showed decreased bacterial diversity, enriched Firmicutes and Proteobacteria, decreased Bacteroidetes and Fusobacteria, and increased ratio of Firmicutes to Bacteroidetes. Bacteroidetes and Bacteroides had the highest number of significant correlations with liver-adipose tissue axis outcomes. In silico analysis of gut microbiome in NAFLD obese patients revealed a depletion in Bacteroides, which also correlated to disease outcomes. CONCLUSION: This mice model gathered suitable phenotypical alterations in gut-liver-adipose tissue axis that resembled NAFLD associated with metabolic disorders in humans and may be considered for preclinical investigation.

Agreement between histopathological and intraoperative classifications for pediatric appendicitis and its relationship with the post-operative clinical outcome.

Introduction: Some studies have shown poor agreement between intraoperative and histopathological classifications for appendicitis, despite their routine use in clinical practice. Objective: To investigate the agreement between histopathological and intraoperative classifications for pediatric appendicitis and evaluate the predictive potential of these classifications for the post-operative outcome. Methods: A retrospective, longitudinal, observational single-center study, carried out with 485 patients up to15 years of age, with a confirmed diagnosis of acute appendicitis by histopathological evaluation. The histopathological results classified the appendices as uncomplicated appendicitis when there was confirmation of the diagnosis of appendicitis without necrosis or perforation and complicated appendicitis when there was extensive necrotic tissue in the outer layer of the appendix or signs of perforation. The intraoperative findings were classified as uncomplicated appendicitis when the appendix presented with hyperemia and edema or fibrinous exudate and complicated appendicitis when the appendix showed necrosis, abscess, or perforation. The kappa index determined the agreement and the prediction relationships using a generalized linear model. Results: 43.9% of cases were classified as complicated appendicitis by histopathological evaluation and 49.7% by intraoperative classification. The agreement analysis between the histopathological and intraoperative classification showed a moderate agreement, with a Kappa index of 0.419 (0.337-0.501). There was an association (P < 0.05) between the intraoperative classification and the post-operative clinical outcomes (time to start feeding, fever, intraabdominal collection, length of stay, the need for antibiotic therapy changing, and need for ICU). There was no association between histopathological classification and post-operative outcomes. Conclusion: The agreement between the two classifications was moderate, and the intraoperative classification was able to predict the post-operative clinical outcomes.

Evaluation of carcinogenic potential of diuron in a rat mammary two-stage carcinogenesis model.

This study aimed to evaluate the carcinogenic potential of the herbicide Diuron in a two-stage rat medium-term mammary carcinogenesis model initiated by 7,12-dimethylbenz(a)anthracene (DMBA). Female seven-week-old Sprague-Dawley (SD) rats were allocated to six groups: groups G1 to G4 received intragastrically (i.g.) a single 50 mg/kg dose of DMBA; groups G5 and G6 received single administration of canola oil (vehicle of DMBA). Groups G1 and G5 received a basal diet, and groups G2, G3, G4, and G6 were fed the basal diet with the addition of Diuron at 250, 1250, 2500, and 2500 ppm, respectively. After twenty-five weeks, the animals were euthanized and mammary tumors were histologically confirmed and quantified. Tumor samples were also processed for immunohistochemical evaluation of the expressions of proliferating cell nuclear antigen (PCNA), cleaved caspase-3, estrogen receptor-α (ER-α), p63, bcl-2, and bak. Diuron treatment did not increase the incidence or multiplicity of mammary tumors (groups G2 to G4 versus Group G1). Also, exposure to Diuron did not alter tumor growth (cell proliferation and apoptosis indexes) or immunoreactivity to ER-α, p63 (myoephitelial marker), or bcl-2 and bak (apoptosis regulatory proteins). These findings indicate that Diuron does not have a promoting potential on mammary carcinogenesis in female SD rats initiated with DMBA.

Peutz-Jeghers syndrome: an unusual autopsy finding in pregnancy.

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant polyposis entity that often remains undiagnosed. The major problems associated with PJS are acute complications due to (i) polyp-related intestinal obstruction, (ii) intussusception, and (iii) the risk of cancer in the long-term. We report the case of a 32-year-old female who presented at the emergency room with signs of acute abdomen and died during the clinical workup. She had a one-month history of nausea, vomiting, and diarrhea and was pregnant at about 30 weeks. There was no contributing past history except for undergoing small bowel resection in infancy. The postmortem examination revealed multiple arborizing polyps throughout the gastrointestinal tract, chiefly in the small bowel. Intestinal obstruction was found at the proximal jejunum with necrosis, perforation, and peritonitis. Histologically, the polyps were composed of tree branch-like bundles of smooth muscle covered by normal-appearing glandular epithelium, confirming the diagnosis of hamartomatous polyps. No malignant or premalignant lesions were detected in the gastrointestinal tract or other organs. This case was an opportunity to analyze the natural history and the pathological features of the Peutz-Jeghers syndrome in an adult and to investigate the presence of neoplastic lesions associated with this condition.