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Although perianal Crohn's disease (PCD) is highly associated with the exacerbated inflammation, the molecular basis and immunological signature that distinguish patients who present a history of perianal lesions are still unclear. This paper aims to define immunological characteristics related to PCD. In this cross-sectional observational study, we enrolled 20 healthy controls and 39 CD patients. Blood samples were obtained for the detection of plasma cytokines and lipopolysaccharides (LPS). Peripheral blood mononuclear cells (PBMCs) were phenotyped by flow cytometry. Leukocytes were stimulated with LPS or anti-CD3/anti-CD28 antibodies. Our results show that CD patients had augmented plasma interleukin (IL)-6 and LPS. However, their PBMC was characterized by decreased IL-6 production, while patients with a history of PCD produced higher IL-6, IL-8, and interferon-γ, along with decreased tumor necrosis factor alpha (TNF). CD patients had augmented FoxP3 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) regulatory markers, though the PCD subjects presented a significant reduction in CTLA-4 expression. CTLA-4 as well as IL-6 and TNF responses were able to distinguish the PCD patients from those who did not present perianal complications. In conclusion, IL-6, TNF, and CTLA-4 exhibit a distinct expression pattern in CD patients with a history of PCD, regardless of disease activity. These findings clarify some mechanisms involved in the development of the perianal manifestations and may have a great impact on the disease management.
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Antígeno CTLA-4 , Enfermedad de Crohn , Humanos , Antígeno CTLA-4/metabolismo , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/sangre , Masculino , Femenino , Adulto , Estudios Transversales , Persona de Mediana Edad , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Interleucina-6/sangre , Lipopolisacáridos/inmunología , Citocinas/sangre , Citocinas/metabolismo , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/metabolismo , Factores de Transcripción Forkhead/metabolismoRESUMEN
Lipid and cholinergic mediators are inflammatory regulators, but their role in the immunopathology of COVID-19 is still unclear. Here, we used human blood and tracheal aspirate (TA) to investigate whether acetylcholine (Ach), fatty acids (FAs), and their derived lipid mediators (LMs) are associated with COVID-19 severity. First, we analyzed the perturbation profile induced by SARS-CoV-2 infection in the transcriptional profile of genes related to the ACh and FA/LM pathways. Blood and TA were used for metabolomic and lipidomic analyses and for quantification of leukocytes, cytokines, and ACh. Differential expression and coexpression gene network data revealed a unique transcriptional profile associated with ACh and FA/LM production, release, and cellular signaling. Transcriptomic data were corroborated by laboratory findings: SARS-CoV-2 infection increased plasma and TA levels of arachidonic acid, 5-hydroxy-6E,8Z,11Z,14Z-eicosatetraenoic acid, 11-hydroxy-5Z,8Z,12E,14Z-eicosatetraenoic acid, and ACh. TA samples also exhibited high levels of PGE2, thromboxane B2, 12-oxo-5Z,8Z,10E,14Z-eicosatetraenoic acid, and 6-trans-leukotriene B4 Bioinformatics and experimental approaches demonstrated robust correlation between transcriptional profile in Ach and FA/LM pathways and parameters of severe COVID-19. As expected, the increased neutrophil-to-lymphocyte ratio, neutrophil counts, and cytokine levels (IL-6, IL-10, IL-1ß, and IL-8) correlated with worse clinical scores. Glucocorticoids protected severe and critical patients and correlated with reduced Ach levels in plasma and TA samples. We demonstrated that pulmonary and systemic hyperinflammation in severe COVID-19 are associated with high levels of Ach and FA/LM. Glucocorticoids favored the survival of patients with severe/critical disease, and this effect was associated with a reduction in ACh levels.
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Acetilcolina , COVID-19 , Ácido Araquidónico , Ácidos Araquidónicos/farmacología , Ácidos Grasos , Glucocorticoides , Humanos , SARS-CoV-2RESUMEN
COVID-19 has a broad spectrum of clinical manifestations associated with the host immune response heterogeneity. Despite the advances in COVID-19 research, it is still crucial to seek a panel of molecular markers that enable accurate stratification of COVID-19 patients. Here, we performed a study that combined analysis of blood transcriptome, demographic data, clinical aspects and laboratory findings from 66 participants classified into different degrees of COVID-19 severity and healthy subjects. We identified a perturbation in blood-leukocyte transcriptional profile associated with COVID-19 aggravation, which was mainly related to processes that disfavoured lymphocyte activation and favoured neutrophil activation. This transcriptional profile stratified patients according to COVID-19 severity. Hence, it enabled identification of a turning point in transcriptional dynamics that distinguished disease outcomes and non-hospitalized from hospitalized moderate patients. Central genes of this unique neutrophil signature were S100A9, ANXA3, CEACAM6, VNN1, OLFM4, IL1R2, TCN1 and CD177. Our study indicates the molecular changes that are linked with the differing clinical aspects presented by humans when suffering from COVID-19, which involve neutrophil activation.
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COVID-19 , Humanos , COVID-19/genética , Neutrófilos , Transcriptoma , BiomarcadoresRESUMEN
BACKGROUND: Sex-determined differences are rarely addressed in the management of diseases, despite well-known contrasting outcomes between female and male patients. In COVID-19 there is a remarkable disparity, with higher rates of mortality and more severe acute disease in men compared to women, who are mostly affected by long COVID-19. Furthermore, whether androgens play a protective or detrimental role in COVID-19 is still a matter of debate. Hence, the adequate management of the disease, especially regarding men presenting acute disease aggravation, still needs important data to elucidate the interplay between sex hormones and host immune responses that drive the worse evolution in male patients. METHODS: A cohort of 92 controls and 198 non-severe and severe COVID-19 patients, from both sexes, was assessed for clinical outcomes, plasma steroids, gonadotropins, sex hormone binding globulin (SHBG) and immune mediators, before vaccination. These data were correlated with the global gene expression of blood leukocytes. The androgen receptor (AR) signaling pathway was investigated by transcriptomics and tracheal aspirate was obtained from severe patients for SARS-COV-2 quantification in the respiratory tract. The interplay among clinical, endocrine and immunological data deciphered the sex differences in COVID-19. Importantly, statistical analyses, using 95% confidence interval, considered confounding factors such as age and comorbidities, to definitely parse the role of androgens in the disease outcome. RESULTS: There were notable contrasting levels of testosterone and dihydrotestosterone (DHT) throughout the disease course in male but not female patients. Inflammatory mediators presented significant negative correlations with testosterone, which was partially dependent on age and diabetes in men. Male subjects with severe COVID-19 had a significant up regulation of the AR signaling pathway, including modulation of TMPRSS2 and SRD5A1 genes, which are related to the viral infection and DHT production. Indeed, men had a higher viral load in the tracheal aspirate and levels of DHT were associated with increased relative risk of death. In contrast, the testosterone hormone, which was notably reduced in severe disease, was significantly related with susceptibility to COVID-19 worsening in male patients. Secondary hypogonadism was ruled out in the male severe COVID-19 subjects, as FSH, LH, and SHBG levels were not significantly altered. Instead, these subjects tended to have increased gonadotropin levels. Most interestingly, in this study we identified, for the first time, combined sets of clinical and immunoendocrine parameters that together predicted progression from non-severe to severe COVID-19 in men. One of the limitations of our study was the low or undetectable levels of DHT in many patients. Then, the evaluation of enzymes related to biosynthesis and signaling by androgens was mandatory and reiterated our findings. CONCLUSIONS: These original results unraveled the disease immunoendocrine regulation, despite vaccination or comorbidities and pointed to the fundamental divergent role of the androgens testosterone and DHT in the determination of COVID-19 outcomes in men. Therefore, sex-specific management of the dysregulated responses, treatments or public health measures should be considered for the control of COVID-19 pandemic.
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BACKGROUND: The effectiveness of ustekinumab (UST) in the treatment of Crohn's disease (CD) has been demonstrated in the pivotal Phase 3 UNITI 1 and 2 and IM-UNITI studies in both anti-TNF-naïve and anti-TNF-exposed patients. Given the selective nature of pivotal trial designs, real-world effectiveness and safety studies are warranted. We report our experience with UST treatment in a large, real-world multicenter cohort of Brazilian patients with CD. METHODS: We performed a retrospective multicenter study including patients with CD, predominantly biologically refractory CD, who received UST. The primary endpoint was the proportion of patients in clinical remission at weeks 8, 24 and 56. Possible predictors of clinical and biological response/remission and safety outcomes were also assessed. RESULTS: Overall, 245 CD (mean age 39.9 [15-87]) patients were enrolled. Most patients (86.5%) had been previously exposed to biologics. According to nonresponder imputation analysis, the proportions of patients in clinical remission at weeks 8, 24 and 56 were 41.0% (n = 98/239), 64.0% (n = 153/239) and 39.3% (n = 94/239), respectively. A biological response was achieved in 55.4% of patients at week 8, and 59.3% were in steroid-free remission at the end of follow-up. No significant differences in either clinical or biological remission were noted between bio-naïve and bio-experienced patients. Forty-eight patients (19.6%) presented 60 adverse events during the follow-up, of which 8 (13.3%) were considered serious adverse events (3.2% of 245 patients). Overall, a proximal disease location, younger age, perianal involvement, and smoking were associated with lower rates of clinical remission over time. CONCLUSIONS: UST therapy was effective and safe in the long term in this large real-life cohort of Brazilian patients with refractory CD, regardless of previous exposure to other biological agents.
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Enfermedad de Crohn , Ustekinumab , Adulto , Brasil , Enfermedad de Crohn/inducido químicamente , Enfermedad de Crohn/tratamiento farmacológico , Humanos , Inducción de Remisión , Estudios Retrospectivos , Resultado del Tratamiento , Inhibidores del Factor de Necrosis Tumoral , Factor de Necrosis Tumoral alfa , Ustekinumab/efectos adversosRESUMEN
BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers worldwide; it is the fourth leading cause of death in the world and the third in Brazil. Mutations in the APC, DCC, KRAS and TP53 genes have been associated with the progression of sporadic CRC, occurring at defined pathological stages of the tumor progression and consequently modulating several genes in the corresponding signaling pathways. Therefore, the identification of gene signatures that occur at each stage during the CRC progression is critical and can present an impact on the diagnosis and prognosis of the patient. In this study, our main goal was to determine these signatures, by evaluating the gene expression of paired colorectal adenoma and adenocarcinoma samples to identify novel genetic markers in association to the adenoma-adenocarcinoma stage transition. METHODS: Ten paired adenoma and adenocarcinoma colorectal samples were subjected to microarray gene expression analysis. In addition, mutations in APC, KRAS and TP53 genes were investigated by DNA sequencing in paired samples of adenoma, adenocarcinoma, normal tissue, and peripheral blood from ten patients. RESULTS: Gene expression analysis revealed a signature of 689 differentially expressed genes (DEG) (fold-change> 2, p< 0.05), between the adenoma and adenocarcinoma paired samples analyzed. Gene pathway analysis using the 689 DEG identified important cancer pathways such as remodeling of the extracellular matrix and epithelial-mesenchymal transition. Among these DEG, the ETV4 stood out as one of the most expressed in the adenocarcinoma samples, further confirmed in the adenocarcinoma set of samples from the TCGA database. Subsequent in vitro siRNA assays against ETV4 resulted in the decrease of cell proliferation, colony formation and cell migration in the HT29 and SW480 colorectal cell lines. DNA sequencing analysis revealed KRAS and TP53 gene pathogenic mutations, exclusively in the adenocarcinomas samples. CONCLUSION: Our study identified a set of genes with high potential to be used as biomarkers in CRC, with a special emphasis on the ETV4 gene, which demonstrated involvement in proliferation and migration.
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Adenocarcinoma/genética , Adenoma/genética , Neoplasias Colorrectales/genética , Genes Relacionados con las Neoplasias , Proteínas de Neoplasias/fisiología , Proteínas Proto-Oncogénicas c-ets/fisiología , Adenocarcinoma/química , Adenocarcinoma/patología , Adenoma/química , Adenoma/patología , Anciano , Biomarcadores de Tumor/genética , Brasil , División Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Transformación Celular Neoplásica/genética , Neoplasias Colorrectales/química , Neoplasias Colorrectales/patología , ADN de Neoplasias/genética , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas c-ets/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-ets/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Análisis de Matrices Tisulares , Transcriptoma , Ensayo de Tumor de Célula MadreRESUMEN
BACKGROUND: Since HLA-G is an immune checkpoint molecule and since Crohn's disease (CD) and ulcerative colitis (UC) exhibit deregulated immune-mediated mechanisms, we aimed to evaluate intestinal HLA-G expression and soluble HLA-G (sHLA-G) levels in CD/UC patients stratified according to the CD phenotype/localization and UC extension. METHODS: HLA-G tissue expression was assessed by immunohistochemistry in biopsies collected from 151 patients (90 CD, 61 UC) and in surgical resection specimens (28 CD, 12 UC). Surgical material from 24 healthy controls was also assessed. Plasma sHLA-G levels (97 CD, 81 UC, and 120 controls) were evaluated using ELISA. RESULTS: HLA-G expression was similarly observed in the intestinal epithelial cells of control and CD/UC specimens. However, in biopsies, the plasma cells/lymphocytes infiltrating the lamina propria in CD/UC presented (1) increased HLA-G expression compared to controls (P < 0.0001), (2) greater cell staining in UC cells than in CD cells irrespective of disease extent (P = 0.0011), and (3) an increased number of infiltrating cells in the inflammatory CD phenotype compared to that in the stenosing and fistulizing phenotypes (P = 0.0407). In surgical specimens, CD/UC patients exhibited higher infiltrating cell HLA-G expression in lesion areas than in margins. sHLA-G levels were higher in UC/CD patients (P < 0.0001) than in controls, but no difference was observed between diseases. CONCLUSIONS: Increased infiltrating cell HLA-G expression associated with increased sHLA-G levels in CD/UC patients may reflect ongoing host strategies to suppress chronic inflammation.
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Colitis Ulcerosa/patología , Enfermedad de Crohn/patología , Regulación de la Expresión Génica/inmunología , Antígenos HLA-G/metabolismo , Adolescente , Adulto , Femenino , Antígenos HLA-G/genética , Humanos , Inflamación , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
BACKGROUND AND PURPOSE: Despite the advances achieved in surgical techniques in recent years, an intestinal stoma is still needed in many patients undergoing colorectal surgery. However, the intestinal stoma may be associated with serious complications and the need for a second surgical procedure. In extreme cases, when it is not possible to access the abdominal cavity, the management of a complicated stoma is challenging. The purpose of this study was to describe the use of a Dacron vascular prosthesis (DVP) in patients with intestinal stoma complications. METHODS: In patients with a shallow, superficial stoma or mucocutaneous separation (MCS), we sutured the prosthesis in the intestinal loop (at the edge of an intestinal fistula) to create a device to direct the fecal content to the collection bag. RESULTS: We included 9 patients in this series (colorectal cancer, n = 5; Crohn's disease, n = 2; giant abdominal hernia and morbid obesity, n = 2). The results obtained were promising since they showed good evolution in patients with severe intestinal complications and an impossibility of surgical correction of the stoma. Five patients presented complete healing, and two patients presented partial healing. There were two deaths caused by sepsis, which were not related to the surgical procedure. With this technique, there was a reduction in the leakage of intestinal contents into the peritoneal cavity and an increase in the healing of the peristomal dermatitis in most of the patients. The DVP could possibly represent a surgical alternative in selected patients with complicated stomas when surgical correction may not be a suitable option. CONCLUSIONS: The authors recommend this technique for selected complex cases of stoma complications after unsuccessful attempts to adapt collecting equipment. The placement of the DVP allowed the peristomal skin to heal and improved the contamination of the peritoneal cavity.
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Enterostomía , Estomas Quirúrgicos , Prótesis Vascular , Humanos , Tereftalatos Polietilenos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estomas Quirúrgicos/efectos adversosRESUMEN
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.
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Metilnitronitrosoguanidina/toxicidad , Neoplasias Experimentales/inducido químicamente , Neoplasias del Recto/inducido químicamente , Administración Rectal , Animales , Carcinogénesis/inducido químicamente , Carcinogénesis/patología , Colonoscopía/métodos , Femenino , Humanos , Metilnitronitrosoguanidina/administración & dosificación , Ratones , Neoplasias Experimentales/diagnóstico , Neoplasias Experimentales/patología , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/patología , Recto/diagnóstico por imagen , Recto/efectos de los fármacos , Recto/patologíaRESUMEN
PURPOSE: We investigated the possible beneficial effects that hyperbaric oxygen therapy could offer in different brain structures affected by ventriculomegaly in pup rats submitted to experimental hydrocephalus. METHODS: Seven-day-old Wistar rats were submitted to hydrocephalus by intracisternal injection of 10% kaolin into the cisterna magna. The animals were divided into four groups: control (n = 5); control with HBOT (3ATA/2 h/day) (n = 5); untreated hydrocephalic (n = 10); hydrocephalic treated with HBOT (3ATA/2 h/day) (n = 10). The treatment with HBOT was performed daily for 14 days post-induction of hydrocephalus. To evaluate the response to treatment, behavioral tests (open field, Morris water maze, and activity monitor) were performed. After 14 days, the animals were euthanized, and the brain was removed for histological (hematoxylin-eosin and solochrome-cyanine) and immunohistochemical (GFAP and Ki-67) studies. RESULTS: The hyperbaric treatment, although not causing changes in ventricular enlargement, resulted in a significant improvement in the behavioral performance (p = 0.0001), with greater agility and exploration of the environment, preservation of spatial memory, and greater learning capacity (p = 0.0001). Through the immunohistochemical study, the astrocytic activity (glial fibrillary acidic protein) in the corpus callosum (p = 0.0001) and in the germinative matrix (p = 0.0033) was significantly reduced as compared to that in the H group. CONCLUSION: The results suggest that hyperbaric treatment bettered the behavioral performance and offered benefits to the structures affected by the ventricular increase helping to recover the brain damages. In this way, the HBOT it can be considered an adjuvant therapy for the treatment of hydrocephalus.
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Lesiones Encefálicas/patología , Gliosis/patología , Hidrocefalia/patología , Oxigenoterapia Hiperbárica/métodos , Animales , Lesiones Encefálicas/etiología , Hidrocefalia/complicaciones , Masculino , Ratas , Ratas WistarAsunto(s)
Endometriosis , Laparoscopía , Disección , Endometriosis/cirugía , Femenino , Humanos , Recto/cirugíaRESUMEN
PURPOSE: Determine the effect of hyperbaric oxygen treatment in skeletal muscle of rats submitted to total acute left hindlimb ischemia. METHODS: An experimental study was designed using 48 Wistar rats divided into four groups (n = 12): Control; Ischemia (I)--total hindlimb ischemia for 270 minutes; Hyperbaric oxygen treatment during ischemia (HBO2)--total hindlimb ischemia for 270 minutes and hyperbaric oxygen during the first 90 minutes; Pre-treatment with hyperbaric oxygen (PHBO2)--90 minutes of hyperbaric oxygen treatment before total hindlimb ischemia for 270 minutes. Skeletal muscle injury was evaluated by measuring levels of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total creatine phosphokinase (CPK); muscular malondialdehyde (MDA), muscular glycogen, and serum ischemia-modified albumin (IMA). RESULTS: AST was significantly higher in I, HBO2 and PHBO2 compared with control (P = .001). There was no difference in LDH. CPK was significantly higher in I, HBO2 and PHBO2, compared with control (p = .014). MDA was significantly higher in PHBO2, compared with other groups (p = .042). Glycogen was significantly decreased in I, HBO2 and PHBO2, compared with control (p < .001). CONCLUSION: Hyperbaric oxygen treatment in acute total hindlimb ischemia exerted no protective effect on muscle injury, regardless of time of application. When applied prior to installation of total ischemia, hyperbaric oxygen treatment aggravated muscle injury.
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Miembro Posterior/irrigación sanguínea , Oxigenoterapia Hiperbárica , Isquemia/terapia , Músculo Esquelético/irrigación sanguínea , Enfermedad Aguda , Animales , Aspartato Aminotransferasas/análisis , Creatina Quinasa/análisis , Glucógeno/análisis , Isquemia/metabolismo , L-Lactato Deshidrogenasa/análisis , Masculino , Malondialdehído/análisis , Músculo Esquelético/metabolismo , Distribución Aleatoria , Ratas , Ratas Wistar , Informe de Investigación , Albúmina Sérica/análisis , Factores de TiempoRESUMEN
PURPOSE: To evaluate patient characteristics and factors associated with surgical resection in patients with Crohn's disease (CD). METHODS: An analysis was performed on data from 295 patients with CD in follow-up from 2001 to 2018. Medical record data comprised age, gender, location, behavior and duration of the CD, smoking, and extraintestinal manifestation. Patients were divided into two groups according to the presence or absence of surgical resection. RESULTS: Out of the 295 patients with CD, 155 underwent surgical resection (53.2% male, mean age: 43.88 ± 14.35 years). The main indications for surgery were stenosis (44.5%), clinical intractability (15.5%), and intra-abdominal fistulas (15.5%). Smoking (p < 0.001), longer CD duration (p < 0.0001), ileo-colonic location (p = 0.003), stenosing behavior (p < 0.0001), and fistulizing behavior (p < 0.0001) were significantly associated with surgical resection. Initial use of biological was significantly more frequent in the group of patients without surgical resection (p < 0.001). CONCLUSIONS: Patients with CD still frequently need surgical treatment. Smoking (current or past), longer disease time, stenosing and fistulizing behavior, and ileo-colonic localization in CD patients were associated with a higher risk of surgery. Awareness about factors associated with unfavorable outcome allows such patients to be treated more appropriately.
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Enfermedad de Crohn , Humanos , Masculino , Adulto , Persona de Mediana Edad , Femenino , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/cirugía , Íleon , Estudios RetrospectivosRESUMEN
Tumor hypoxia may compromise the results of chemotherapy for treating colorectal cancer because it stimulates angiogenesis and the release of tumor growth factors. Hyperbaric oxygen (HBO) supplementation may potentiate the effects of chemotherapy in such cases. This study aimed to assess the effect of HBO therapy combined with chemotherapy on the treatment of colorectal cancer in mice. C57BL6 mice were submitted to the intrarectal instillation of N-methyl-N-nitrosoguanidine (MNNG) and treated with 5-fluorouracil (5FU) and/or HBO therapy. The MNNG group presented the highest dysplastic crypt rate. The 5FU + HBO group presented the highest rate of apoptotic cells per dysplastic crypt. The 5FU group presented the highest expression of hypoxia-inducible factor-1 alpha and CD44. HBO therapy increased the effect of 5FU on the treatment of the experimental colorectal neoplasia in mice.