Diagnostic dilemma and challenges in management: Hirschsprung's disease, anal stenosis and reduced interstitial cells of Cajal enteric mesenchymopathy.

Hirschsprung's disease (HD) is one of the most well-known gastrointestinal motility disorders. Diagnosis and management of other lesser-known motility disorders are often challenging and tedious. We describe a teenager who was severely constipated from birth and needed intensive care admissions for life-threatening enterocolitis. She also had concomitant anal stenosis. Several rectal biopsies were unable to yield a conclusive diagnosis. Surgical level of resection had to be identified based on the motility of the bowel as determined by transit studies using oral ingestion of a milk feed labelled with Technetium-99m colloid. After completion of all operative stages, histopathological examination of the excised specimens concluded that she had short-segment HD associated with reduced interstitial cells of Cajal in the large bowel. She is currently continent, evacuating voluntarily approximately four times a day and is relieved of all her symptoms.

The small and large intestine contain related mesenchymal subsets that derive from embryonic Gli1+ precursors.

The intestinal lamina propria contains a diverse network of fibroblasts that provide key support functions to cells within their local environment. Despite this, our understanding of the diversity, location and ontogeny of fibroblasts within and along the length of the intestine remains incomplete. Here we show that the small and large intestinal lamina propria contain similar fibroblast subsets that locate in specific anatomical niches. Nevertheless, we find that the transcriptional profile of similar fibroblast subsets differs markedly between the small intestine and colon suggesting region specific functions. We perform in vivo transplantation and lineage-tracing experiments to demonstrate that adult intestinal fibroblast subsets, smooth muscle cells and pericytes derive from Gli1-expressing precursors present in embryonic day 12.5 intestine. Trajectory analysis of single cell RNA-seq datasets of E12.5 and adult mesenchymal cells suggest that adult smooth muscle cells and fibroblasts derive from distinct embryonic intermediates and that adult fibroblast subsets develop in a linear trajectory from CD81+ fibroblasts. Finally, we provide evidence that colonic subepithelial PDGFRαhi fibroblasts comprise several functionally distinct populations that originate from an Fgfr2-expressing fibroblast intermediate. Our results provide insights into intestinal stromal cell diversity, location, function, and ontogeny, with implications for intestinal development and homeostasis.

Histaminergic System and Inflammation-Related Genes in Normal Large Intestine and Adenocarcinoma Tissues: Transcriptional Profiles and Relations.

Transcriptional analyses such as microarray data have contributed to the progress in the diagnostics and therapy of colorectal cancer (CRC). The need for such research is still present because of the disease being common in both men and women with a high second position in cancer rankings. Little is known about the relations between the histaminergic system and inflammation in the large intestine and CRC. Therefore, the aim of this study was to evaluate the expression of genes related to the histaminergic system and inflammation in the CRC tissues at three cancer development designs: all tested CRC samples, low (LCS) and high (HCS) clinical stage, and four clinical stages (CSI-CSIV), to the control. The research was carried out at the transcriptomic level, analysing hundreds of mRNAs from microarrays, as well as carrying out RT-PCR analysis of histaminergic receptors. The following histaminergic mRNAs: GNA15, MAOA, WASF2A, and inflammation-related: AEBP1, CXCL1, CXCL2, CXCL3, CXCL8, SPHK1, TNFAIP6, were distinguished. Among all analysed transcripts, AEBP1 can be considered the most promising diagnostic marker in the early stage of CRC. The results showed 59 correlations between differentiating genes of the histaminergic system and inflammation in the control, control and CRC, and CRC. The tests confirmed the presence of all histamine receptor transcripts in both the control and colorectal adenocarcinoma. Significant differences in expression were stated for HRH2 and HRH3 in the advanced stages of CRC adenocarcinoma. The relations between the histaminergic system and inflammation-linked genes in both the control and the CRC have been observed.

Quality of Life in Patients over Age 65 after Intestinal Ostomy Creation as Treatment of Large Intestine Disease.

INTRODUCTION: For patients with severe intestinal diseases, ostomy surgery can be health-preserving and even lifesaving. Unfortunately, stoma creation also results in a morbidity that patients must manage. Utilization of the correct ostomy appliances is essential for the patient to regain full daily fitness. Patients also now have access to stoma clinics and fistula support groups where they can receive education and emotional support. AIM: The aim of the study was to assess the quality of life of patients over 65 years of age with an intestinal stoma, created for treatment of severe colorectal disease. MATERIAL AND METHODS: The study involved 100 patients (52 women, 48 men) over the age of 65 with an intestinal stoma. Demographic and medical information was collected. The patients completed diagnostic surveys using the SF-36v2 questionnaire and the author's questionnaire. RESULTS: Analysis demonstrated statistically significant relationships between the quality of life of the patient population and stressors of everyday life. Furthermore, there are statistically significant relationships between quality of life and demographic factors including age, marital status, place of residence, and education. Only gender was not a statistically significant factor. CONCLUSIONS: A lengthened time interval to intestinal stoma creation is associated with an improved quality of life as well as psychological and emotional acceptance of the intestinal stoma. Support relationships with loved ones is associated with the acceptance of an intestinal stoma. There is a relationship between acceptance of an intestinal stoma and demographic factors such as marital status, place of residence, and education. Gender did not show any significant relationship. Stoma complications are not related to the acceptance of an intestinal stoma.

[Current WSES-AAST guidelines on anorectal emergencies-Summary and comments]. / Aktuelle WSES-AAST-Leitlinie zu anorektalen Notfällen ­ Zusammenfassung und Kommentar.

In 2019, the World Society of Emergency Surgery (WSES) and the American Association for the Surgery of Trauma (AAST) generated consensus recommendations for the treatment of anorectal emergencies in Parma, Italy, and published a guideline in 2021. This is the first global guideline dealing with this important topic for surgeons' everyday work. Seven anorectal emergencies were discussed and the guideline recommendations were given according to the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.

Integrated omics analysis reveals the immunologic characteristics of cystic Peyer's patches in the cecum of Bactrian camels.

Bactrian camels have specific mucosa-associated lymphoid tissue (MALT) throughout the large intestine, with species-unique cystic Peyer's patches (PPS) as the main type of tissue. However, detailed information about the molecular characteristics of PPS remains unclear. This study applied a transcriptomic analysis, untargeted metabolomics, and 16S rDNA sequencing to compare the significant differences between PPS and the adjacent normal intestine tissues (NPPS) during the healthy stage of three young Bactrian camels. The results showed that samples from PPS could be easily differentiated from the NPPS samples based on gene expression profile, metabolites, and microbial composition, separately indicated using dimension reduction methods. A total of 7,568 up-regulated and 1,266 down-regulated differentially expressed genes (DEGs) were detected, and an enrichment analysis found 994 DEGs that participated in immune-related functions, and a co-occurance network analysis identified nine hub genes (BTK, P2RX7, Pax5, DSG1, PTPN2, DOCK11, TBX21, IL10, and HLA-DOB) during multiple immunologic processes. Further, PPS and NPPS both had a similar pattern of most compounds among all profiles of metabolites, and only 113 differentially expressed metabolites (DEMs) were identified, with 101 of these being down-regulated. Deoxycholic acid (DCA; VIP = 37.96, log2FC = -2.97, P = 0), cholic acid (CA; VIP = 13.10, log2FC = -2.10, P = 0.01), and lithocholic acid (LCA; VIP = 12.94, log2FC = -1.63, P = 0.01) were the highest contributors to the significant dissimilarities between groups. PPS had significantly lower species richness (Chao1), while Firmicutes (35.92% ± 19.39%), Bacteroidetes (31.73% ± 6.24%), and Proteobacteria (13.96% ± 16.21%) were the main phyla across all samples. The LEfSe analysis showed that Lysinibacillus, Rikenellaceae_RC9_gut_group, Candidatus_Stoquefichus, Mailhella, Alistipes, and Ruminococcaceae_UCG_005 were biomarkers of the NPPS group, while Escherichia_Shigella, Synergistes, Pyramidobacter, Odoribacter, Methanobrevibacter, Cloacibacillus, Fusobacterium, and Parabacteroides were significantly higher in the PPS group. In the Procrustes analysis, the transcriptome changes between groups showed no significant correlations with metabolites or microbial communities, whereas the alteration of metabolites significantly correlated with the alteration of the microbial community. In the co-occurrence network, seven DEMs (M403T65-neg, M329T119-neg, M309T38-neg, M277T42-2-neg, M473T27-neg, M747T38-1-pos, and M482t187-pos) and 14 genera (e.g., Akkermansia, Candidatus-Stoquefichus, Caproiciproducens, and Erysipelatoclostridium) clustered much more tightly, suggesting dense interactions. The results of this study provide new insights into the understanding of the immune microenvironment of the cystic PPS in the cecum of Bactrian camels.

Effects of long-term postgastric infusion of casein or glutamic acid on small intestinal starch digestion and energy balance in cattle.

The objective of this experiment was to evaluate effects of postruminal flows of casein or glutamic acid on small intestinal starch digestion and to quantify changes in energy and nutrient balance. Twenty-four steers (body weight = 179 ± 4 kg) were duodenally infused with raw cornstarch (1.46 ± 0.04 kg/d) and either 413 ± 7.0 g casein/d, 121 ± 3.6 g glutamic acid/d or water (control). Measures of small intestinal starch digestion and nutrient excretion were collected across 4 d after 42 d of infusion and measures of respiration via indirect calorimetry were collected across 2 d after 48 d of infusion. Ileal starch flow was least among calves provided casein, but ileal starch flow was not different between glutamic acid or control. Small intestinal starch digestion tended to be greatest among calves provided casein, least for glutamic acid and intermediate for control. Casein increased ileal flow of ethanol soluble oligosaccharides compared to glutamic acid and control. Large intestinal starch digestion was not different among treatments. By design, N intake was greatest among cattle provided casein, intermediate among calves provided glutamic acid and least for control. Nitrogen retention was greater in response to casein compared to control and glutamic acid. Intake of gross energy from feed was similar across treatments, and gross energy from infusate was greatest for casein, intermediate for glutamic acid and least for control. Variation in gross energy intake from feed resulted in no difference in overall gross energy intake across treatments. Similar to measures of small intestinal starch digestion and N retention, casein increased calories of digestible energy and metabolizable energy, compared to glutamic acid and control, which did not differ. Postruminal infusions did not influence methane production, but heat production was greatest in steers infused with casein, intermediate for steers provided glutamic acid, and least for control. Overall, amounts of energy retained by casein tended to be nearly 34% greater than control, but glutamic acid had no impact on energy balance. Improvement in small intestinal starch digestion in response to casein increased energy and N retained; however, glutamic acid did not influence small intestinal starch digestion and energy or N balance in cattle, which seems to suggest that responses in small intestinal starch digestion to greater postruminal flows of glutamic acid become refractory across greater durations of time.

Small intestinal digestion of starch can provide greater energy from dietary starch in comparison to ruminal fermentation, which can increase performance and improve feed efficiency in cattle fed starch-based diets; however, small intestinal starch digestion in cattle is restricted in comparison to nonruminant animals or to ruminal fermentation of starch. In this experiment, long-term increases in postruminal protein but not glutamic acid increased small intestinal starch digestion, and increases in small intestinal starch digestion resulted in improvements in nitrogen and energy balance. Responses in this study compared to previous reports may suggest effects of increased postgastric flows of glutamic acid in cattle are transient, but that effects of casein are not.

Bioactive polysaccharides promote gut immunity via different ways.

Numerous kinds of bioactive polysaccharides are identified as having intestinal immunomodulatory activity; however, the ways in which the different polysaccharides work differ. Therefore, we selected nine representative bioactive polysaccharides, including xanthan gum, inulin, guar gum, arabinogalactan, carrageenan, glucomannan, araboxylan, xylan, and fucoidan, and compared their intestinal immunomodulatory mechanisms. A cyclophosphamide (CTX)-induced immunosuppressed model was used in this experiment, and the effects of these polysaccharides on the number of T cells in the intestinal mucosa, expression of transcription factors and inflammatory factors, intestinal metabolome and gut microbiota were compared and discussed. The results revealed that the nine polysaccharides promote intestinal immunity in different ways. In detail, guar gum, inulin and glucomannan better alleviated immune suppression in intestinal mucosal T cells. Inulin improved the intestinal microenvironment by significantly upregulating the abundance of Lactobacillus and Monoglobus and promoted short chain fatty acid (SCFA) production. Fucoidan and carrageenan promoted the colonization of the beneficial bacteria Rikenella and Roseburia. In addition, fucoidan, inulin and carrageenan inhibited the colonization of harmful bacteria Helicobacter, upregulated the abundance of Clostridia_UCG-014 and alleviated the accumulation of amino acids, bile acids and indoles in the large intestine. In conclusion, our study uncovered the different intestinal immunomodulatory mechanisms of the different polysaccharides and provided a guideline for the development of superior intestinal immunomodulatory polysaccharides.

Histological study on regional specificity of the mucosal nerve network in the rat large intestine.

Our previous studies and others have revealed detailed characteristics of the mucosal nerve network in the small intestine, but much remains unknown about the corresponding network in the large intestine. We herein investigated regional differences in the expression of neurochemical markers, the nerve network structure, and the cells in contact with nerve fibers by histological analysis using both immunohistochemistry and serial block-face scanning electron microscopy (SBF-SEM). Immunohistochemistry revealed that immunopositive structures for protein gene product 9.5, vasoactive intestinal peptide (VIP), calretinin and vesicular acetylcholine transporter were more prevalent in the lamina propria of the ascending colon than the cecum and descending colon (DC). There was no significant difference in the frequency of most neurochemical markers between the cecum and DC, but the frequencies of VIP+ structures were higher in the cecum than in the DC. SBF-SEM analysis showed that the nerve network structure was more developed on the luminal side of the DC than the cecum. The cells that nerve fibers abundantly contacted were subepithelial and lamina propria fibroblast-like cells and macrophages. In addition, nerve fibers in the cecum were in more frequent contact with immune cells such as macrophages and plasma cells than nerve fibers in the DC. Thus, the present histological analysis suggested that the mucosal nerve network in the large intestine possessed both regional universality and various specificities, and revealed the intimate relationship between the nerve network and immune cells, especially in the cecum.

Nanofiber Fractionalization Stimulates Healing of Large Intestine Anastomoses in Rabbits.

Background: A current topic of ma jor interest in regenerative medicine is the development of novel materials for accelerated healing of sutures, and nanofibers seem to be suitable materials for this purpose. As various studies have shown, nanofibers are able to partially substitute missing extracellular matrix and to stimulate cell proliferation and differentiation in sutures. Therefore, we tested nanofibrous membranes and cryogenically fractionalized nanofibers as potential materials for support of the healing of intestinal anastomoses in a rabbit model. Materials and Methods: We compared cryogenically fractionalized chitosan and PVA nanofibers with chitosan and PVA nanofiber membranes designed for intestine anastomosis healing in a rabbit animal model. The anastomoses were biomechanically and histologically tested. Results: In strong contrast to nanofibrous membranes, the fractionalized nanofibers did show positive effects on the healing of intestinal anastomoses in rabbits. The fractionalized nanofibers were able to reach deep layers that are key to increased mechanical strength of the intestine. Moreover, fractionalized nanofibers led to the formation of collagen-rich 3D tissue significantly exceeding the healing effects of the 2D flat nanofiber membranes. In addition, the fractionalized chitosan nanofibers eliminated peritonitis, significantly stimulated anastomosis healing and led to a higher density of microvessels, in addition to a larger fraction of myofibroblasts and collagen type I and III. Biomechanical tests supported these histological findings. Conclusion: We concluded that the fractionalized chitosan nanofibers led to accelerated healing for rabbit colorectal anastomoses by the targeted stimulation of collagen-producing cells in the intestine, the smooth muscle cells and the fibroblasts. We believe that the collagen-producing cells were stimulated both directly due to the presence of a biocompatible scaffold providing cell adhesion, and indirectly, by a proper stimulation of immunocytes in the suture.

Skrjabinodon castillensis n. sp. (Nematoda:Pharyngodonidae) from the Homonota horrida and H.darwinii (Squamata: Phyllodactylidae) from Argentina and key for the Neotropical species of the genus Skrjabinodon.

Skrjabinodon castillensis n. sp. is described and illustrated here, based on specimens found in the large intestines of Homonota horrida (province San Juan) and Homonota darwinii (province Neuquén) (Squamata: Phyllodactylidae) from Argentina. The new species is assigned to Skrjabinodon based lateral alae present in males, absent in females. Lateral alae beginning midway between lips and nerve ring and ending just posterior to first pair of caudal papillae. Females with vulva near esophageal bulb. In males, caudal alae absent, paired caudal papillae present. Skrjabinodon castillensis n. sp. represents the 9th species from the Neotropical realm. The new species differs from all other species assigned to Skrjabinodon by morphology of tail filament and number of tail filament spines. Skrjabinodon castillensis n. sp. is the only species of this genus known from Argentina. A key to the species of Skrjabinodon in the Neotropical realm is provided.

Apendicitis aguda y el riesgo de tumor maligno oculto. Presentación de un caso y revisión sistemática de la literatura / Acute appendicitis and the risk of hidden malignant tumor. Presentation of a case and systematic review of literature

Introducción: Los tumores apendiculares representan aproximadamente 1% de los tumores malignos del intestino grueso. Más del 50% de las neoplasias primarias del apéndice se manifiestan inicialmente como apendicitis aguda. Métodos: Se reporta caso de paciente masculino que presentó adenocarcinoma invasor en biopsia de pieza quirúrgica de apéndice cecal tras apendicectomía, tomando la decisión de realizar hemicolectomía derecha laparoscópica diferida. Discusión: En este caso y como en la mayoría de los reportes de la bibliografía mundial, el adenocarcinoma simula un cuadro de AA. En un metaanálisis y una revisión sistemática de 2.771 pacientes diagnosticados de masa apendicular inflamatoria (flemón o absceso), Andersson et al. encontró 31 con tumores malignos. Estas lesiones se detectan en el 0,9% al 1,4% de las apendicectomías realizadas para tratar la AA. Conclusión: Este subtipo histológico presenta mayor incidencia de metástasis en los ganglios linfáticos y la supervivencia global era del 47,5%. Es por ello por lo que abogamos por la resección colónica como tratamiento definitivo del adenocarcinoma de apéndice cecal.

INTRODUCTION: Appendulular tumors represent approximately 1% of malignant tumors of the large intestine. More than 50% of the primary neoplasms of the appendix initially manifest as acute appendicitis. Methods: Men's patient who presented invading adenocarcinoma in Cecal Appendix Surgical Party Biopsy after appendectomy, making the decision to perform deferred laparoscopic right hemicolectomy, is reported. Discussion: In this case and as in most world literature reports, adenocarcinoma simulates an AA picture. In a meta -analysis and a systematic review of 2,771 diagnosed patients of inflammatory appendicular mass (phlegmon or abscess), Andersson et al. He found 31 with malignant tumors. These lesions are detected at 0.9% to 1.4% of appendectomies made to treat the AA. Conclusion: This histological subtype has a greater incidence of metastasis in lymph nodes and global survival was 47.5%. That is why we advocate colonic resection as a definitive treatment of cecal appendix adenocarcinoma.

MORPHOLOGICAL AND FUNCTIONAL FEATURES OF THE MUCOUS MEMBRANE OF SMALL AND LARGE INTESTINE IN PATIENTS WITH COVID-19 AND IN POST-COVID-19 PERIOD.

OBJECTIVE: The aim: To reveal the morphological and functional features of the mucous membrane of small and large intestine in patients with COVID-19 and in post-COVID-19 period. PATIENTS AND METHODS: Materials and methods: In the present study, the authors used biopsy and autopsy material represented by the fragments of the mucous membrane of small and large intestine. All studied material was divided into 10 groups. Group 1 (comparison group) included autopsy material from the deceased who did not have COVID-19 during their lifetime. Groups 2-4 included autopsy material from the deceased who had COVID-19 of varying severity during their lifetime. Groups 5-7 included biopsy material from patients who had recovered from COVID-19 of varying severity, while the duration of the post-COVID period ranged from 1 to 50 days. Groups 8-10 included biopsy material from patients who had in anamnesis COVID-19 of varying severity (the duration of the post-COVID period lasted from 51 to 100 days). Histological, immunohistochemical, morphometric and statistical research methods were used. RESULTS: Results: The comparative analysis showed a more expressed deficiency of ACE2 in the mucous membrane of small and large intestine in patients with moderate and severe COVID-19 compared with patients in post-COVID-19 period of different duration. In patients who had moderate and severe COVID-19 in anamnesis, ACE2 deficiency decreases with increasing duration of post-COVID-19 period. In patients recovered from mild COVID-19, the ACE2 content increases with the duration of post-COVID-19 period from 1 to 50 days and corresponds to the norm with the duration of this period from 51 to 100 days. CONCLUSION: Conclusions: The comprehensive morphological study conducted by the authors made it possible, firstly, to clarify the morphological and functional features of the mucous membrane of small and large intestine in patients with COVID-19 of various degrees of severity; secondly, to obtain new data about the morpho-functional state of the mucous membrane of small and large intestine in patients, taking into account different duration of the post-COVID-19 period and the severity of the infection.

Effects of extensive mobilization and tension anastomosis in anorectal reconstruction (experimental study).

PURPOSE: Anorectoplasty and pull-through procedure can be performed with extensive mobilization or tension anastomosis, which can compromise bowel blood perfusion. We aimed to analyze the hypoxia biomarker values and histopathological findings in both conditions to correlate the occurrence of anal stenosis and defecation disorders in experimental models. METHODS: We created anorectal reconstruction models with impaired vascularization of the anorectum (group I) and tension anastomosis (group II) in rats. A third group of animals underwent sham operation (group III) and another as controls (group IV). Hypoxia biomarker values were assessed in all groups. The histopathological changes on the postoperative days 3 and 35, anal stenosis and defecation disorders on day 35 were compared. RESULTS: Hypoxia biomarker values confirmed postoperative ischemia in groups I-III compared to control. Group I and II rats had a similarly pronounced ischemia with histopathologic changes in the anorectum on the postoperative day 3 and accompanied by severe fibrosis on day 35. Compared to the sham operation, both groups showed defecation disorders with significant anal stenoses. CONCLUSION: Extensive rectal mobilization to about the same extent as tension anastomosis has a major impact on postoperative rectal ischemia, resulting in severe fibrotic changes in the anorectum and defecation disorders in the long term.

Localised Delivery of Macromolecules to the Large Intestine: Translation to Clinical Trials.

Oral administration of macromolecules aimed at systemic delivery has been at the forefront of pharmaceutical research for over 50 years. Yet, in terms of clinical translation for systemic delivery, output is limited to five US Food and Drug Administration (FDA)-approved oral peptide products to date, such are the hurdles. Somewhat neglected by comparison but with potentially lower delivery demands, the goal of local delivery of macromolecules directed mostly to the terminal ileum and colon to treat inflammatory bowel conditions has led to a range of macromolecules including gut-restricted peptides, fusion proteins, enzymes, antibodies, and antisense oligonucleotides that have reached clinical trials. While some of these trials reached primary endpoints, others are at early clinical stages, but it is likely that at least a few approvable products will emerge to supplement the current cohort of parenterally administered macromolecules and oral small molecules. The outstanding successes to date are the FDA approvals of two gut-restricted guanylate cyclase C-activating peptides to treat irritable bowel syndrome (constipated). Over-expressed targets for macromolecules in the gut wall of inflammatory bowel disease patients include α4ß7 integrin, TNF-α, CD-3, ICAM-1, and SMAD-7, while reduced responses to IL-10 and melanocortin offer opportunities for macromolecular agonists. In this Leading Article, a landscape of locally delivered macromolecules to access the gut that have recently reached clinical trials is provided.

Organoid (hypermature) ovarian teratomas: Report of four cases, one of which harbored a well-differentiated neuroendocrine tumor / Teratoma hipermaduro u organoide del ovario: descripción de cuatro casos, con un tumor neuroendocrino bien diferenciado en uno de ellos

Organoid (hypermature) teratomas are highly specialized teratomas showing organ formation, most frequently from the digestive tract or bronchial wall. We present four cases of ovarian organoid teratomas, one with a distinguishable mandible with teeth, one with small intestine, one with large intestine containing a well differentiated neuroendocrine tumor and another with both large intestine and bronchial wall. These tumors have a distribution similar to conventional teratomas and usually behave benignly, although cases of malignancy have been reported.(AU)

Los teratomas hipermaduros u organoides son teratomas altamente especializados en los que existe formación de órganos. Los más comunes son del tracto digestivo y de la pared bronquial. Presentamos cuatro casos de teratomas organoides del ovario: uno con formación de mandíbula con estructuras dentales, otro con intestino delgado, otro con intestino grueso con un tumor neuroendocrino bien diferenciado, y otro intestino grueso y pared bronquial. Estos tumores son de comportamiento benigno, aunque se han descrito casos con malignización. Pueden ocurrir en cualquier lugar donde se localicen los teratomas convencionales.(AU)

Identification of trypsin-degrading commensals in the large intestine.

Increased levels of proteases, such as trypsin, in the distal intestine have been implicated in intestinal pathological conditions1-3. However, the players and mechanisms that underlie protease regulation in the intestinal lumen have remained unclear. Here we show that Paraprevotella strains isolated from the faecal microbiome of healthy human donors are potent trypsin-degrading commensals. Mechanistically, Paraprevotella recruit trypsin to the bacterial surface through type IX secretion system-dependent polysaccharide-anchoring proteins to promote trypsin autolysis. Paraprevotella colonization protects IgA from trypsin degradation and enhances the effectiveness of oral vaccines against Citrobacter rodentium. Moreover, Paraprevotella colonization inhibits lethal infection with murine hepatitis virus-2, a mouse coronavirus that is dependent on trypsin and trypsin-like proteases for entry into host cells4,5. Consistently, carriage of putative genes involved in trypsin degradation in the gut microbiome was associated with reduced severity of diarrhoea in patients with SARS-CoV-2 infection. Thus, trypsin-degrading commensal colonization may contribute to the maintenance of intestinal homeostasis and protection from pathogen infection.

A global phylogenomic and metabolic reconstruction of the large intestine bacterial community of domesticated cattle.

BACKGROUND: The large intestine is a colonization site of beneficial microbes complementing the nutrition of cattle but also of zoonotic and animal pathogens. Here, we present the first global gene catalog of cattle fecal microbiomes, a proxy of the large intestine microbiomes, from 436 metagenomes from six countries. RESULTS: Phylogenomics suggested that the reconstructed genomes and their close relatives form distinct branches and produced clustering patterns that were reminiscent of the metagenomics sample origin. Bacterial taxa had distinct metabolic profiles, and complete metabolic pathways were mainly linked to carbohydrates and amino acids metabolism. Dietary changes affected the community composition, diversity, and potential virulence. However, predicted enzymes, which were part of complete metabolic pathways, remained present, albeit encoded by different microbes. CONCLUSIONS: Our findings provide a global insight into the phylogenetic relationships and the metabolic potential of a rich yet understudied bacterial community and suggest that it provides valuable services to the host. However, we tentatively infer that members of that community are not irreplaceable, because similar to previous findings, symbionts of complex bacterial communities of mammals are expendable if there are substitutes that can perform the same task. Video Abstract.

Pathological mechanism of intestinal mucosal barrier injury of large intestine dampness-heat syndrome rats and the protective effect of Yujin powder.

Large intestine dampness-heat syndrome (LIDHS) is frequently-occurring in the inflammatory intestinal disease of animals and human. Yujin powder (YJP) is a classical prescription for treating LIDHS. To explore the pathological mechanism of intestinal mucosal barrier injury of LIDHS and the protection of YJP, the LIDHS rat model was established through imitating the inducing conditions of LIDHS and treated with YJP. The integrity of ileal and colonic mucosa was detected through histopathological examination. The serum DAO, D-LA and ET levels were detected by ELISA. The mRNA and protein expression levels of Occludin, ZO-1 and MUC2 in ileum and colon were detected using RT-PCR and immunohistochemistry methods, respectively. The results showed that the ileal and colonic epithelium of LIDHS rats were destroyed; the serum DAO, D-LA and ET levels were significantly increased; the mRNA and protein expression levels of Occludin, ZO-1 and MUC2 in ileum and colon were all abnormally expressed. After treatment with YJP, the mucosal integrity was restored; the levels of serum DAO, D-LA and ET, mRNA and protein levels of Occludin and ZO-1 in ileum and colon and MUC2 in ileum were back-regulated; however, MUC2 level in colon was further increased. The results demonstrated that the intestinal mucosal barrier was damaged in LIDHS rats and Occludin, ZO-1 and MUC2 were abnormally expressed, and YJP could repair the intestinal mucosal barrier through up-regulating the expression of Occludin and ZO-1 in ileum and colon as well as MUC2 in colon and down-regulating MUC2 in ileum.