Microstructure of as-cast ferritic-pearlitic nodular cast irons

A review of past works on the formation of ferrite and pearlite in nodular cast iron is proposed. The effects of cooling rate after solidification and of nodule count on the formation of both constituents are stressed, though much emphasis is put on alloying elements and impurities

Differences in Metabolite Composition of Aloe barbadensis Mill. Extracts Lead to Differential Effects on Human Blood T Cell Activity In Vitro

Aloe barbadensis Mill. (Aloe) is used for diverse therapeutic properties including immunomodulation. However, owing to the compositionally complex nature of Aloe, bioactive component(s) responsible for its beneficial properties, though thought to be attributed to polysaccharides (acemannan), remain unknown. We therefore aimed to determine the metabolite composition of various commercial Aloe extracts and assess their effects on human blood T cell activity in vitro. Peripheral blood mononuclear cells (PBMC) from healthy donors were stimulated polyclonally in presence or absence of various Aloe extracts. T cell phenotype and proliferation were investigated by flow cytometry. Aloe extracts were analyzed using targeted 1H-NMR spectroscopy for standard phytochemical quality characterization and untargeted gas chromatography mass spectrometry (GC-MS) for metabolite profiling. Aloe extracts differing in their standard phytochemical composition had varying effects on T cell activation, proliferation, apoptosis, and cell-death in vitro, although this was not related to the acemannan content. Furthermore, each Aloe extract had its own distinct metabolite profile, where extracts rich in diverse sugar and sugar-derivatives were associated with reduced T cell activity. Our results demonstrate that all commercial Aloe extracts are unique with distinct metabolite profiles, which lead to differential effects on T cell activity in vitro, independent of the acemannan content

A Possible Mechanism for the Formation of Exploded Graphite in Nodular Cast Irons

In hypereutectic nodular cast irons, primary precipitation of graphite may lead to graphite flotation in thick section castings. Graphite degeneracy such as so-called exploded graphite is then often associated with this flotation phenomenon and it appears as precipitates where the nodular form is replaced by star-like or flower-like shape. It has been reported that exploded graphite develops after the primary spheroidal nodules have reached some tens of microns in diameter. In this contribution, a model for this transition is presented

Animal health beyond the single disease approach – A role for veterinary herd health management in low-income countries?

In order to identify and evaluate health related constraints faced by Ugandan pig farmers, a veterinary herd health management approach (VHHM) was applied in 20 randomly selected pig farms in the Lira district, Uganda. Regular herd visits were conducted between July 2018 and June 2019, using e.g. interviews, observations, clinical examinations and laboratory analyzes to gather qualitative and quantitative data on relevant aspects of the production. The pig farmers kept on average 18.6 pigs, including 2.6 sows/year. The production figures varied considerably but were generally poor. The sows produced 1.6 litters/year and 8.2 piglets born alive per litter, the average daily gain was 101 g/day, and the mortality in growers was 9.7%. Four major constraints were identified; poor nutrition, infectious diseases, inferior biosecurity, and poor reproductive management. The quantity and quality of feed was suboptimal. Endo- and ectoparasites were very common, causing diarrhea, bronchitis, pneumonia, skin lesions and pruritus. Post-weaning diarrhea associated with enterotoxigenic Escherichia coli was important in the two largest herds, and parvoviral antibodies were found in seven herds, two experiencing problems with mummified fetuses. Biosecurity practices were insufficient and inconsistent, with free-ranging pigs and the use of village boars being the major risks. Reproductive figures were affected by poor estrus detection and service management. Overall, farmers lacked important knowledge on good management practices. In conclusion, the VHHM identified several important constraints that should be addressed in order to increase the productivity of Ugandan pig herds

Fecal luminal factors from patients with irritable bowel syndrome induce distinct gene expression of colonoids

Background: Alteration of the host-microbiota cross talk at the intestinal barrier may participate in the pathophysiology of irritable bowel syndrome (IBS). Therefore, we aimed to determine effects of fecal luminal factors from IBS patients on the colonic epithelium using colonoids. Methods: Colon-derived organoid monolayers, colonoids, generated from a healthy subject, underwent stimulation with fecal supernatants from healthy subjects and IBS patients with predominant diarrhea, phosphate-buffered saline (PBS), or lipopolysaccharide (LPS). Cytokines in cell cultures and fecal LPS were measured by ELISA and mRNA gene expression of monolayers was analyzed using Qiagen RT2 Profiler PCR Arrays. The fecal microbiota profile was determined by the GA-map™ dysbiosis test and the fecal metabolite profile was analyzed by untargeted liquid chromatography/mass spectrometry. Key results: Colonoid monolayers stimulated with fecal supernatants from healthy subjects (n\ua0=\ua07), PBS (n\ua0=\ua04) or LPS (n\ua0=\ua03) presented distinct gene expression profiles, with some overlap (R2Y\ua0=\ua00.70, Q2=\ua00.43). Addition of fecal supernatants from healthy subjects and IBS patients (n\ua0=\ua09) gave rise to different gene expression profiles of the colonoid monolayers (R2Y\ua0=\ua00.79, Q2=\ua00.64). Genes (n\ua0=\ua022) related to immune response (CD1D, TLR5) and barrier integrity (CLDN15, DSC2) contributed to the separation. Levels of proinflammatory cytokines in colonoid monolayer cultures were comparable when stimulated with fecal supernatants from either donor types. Fecal microbiota and metabolite profiles, but not LPS content, differed between the study groups. Conclusions: Fecal luminal factors from IBS patients induce a distinct colonic epithelial gene expression, potentially reflecting the disease pathophysiology. The culture of colonoids from healthy subjects with fecal supernatants from IBS patients may facilitate the exploration of IBS related intestinal micro-environmental and barrier interactions

A Distinct Faecal Microbiota and Metabolite Profile Linked to Bowel Habits in Patients with Irritable Bowel Syndrome

Patients with irritable bowel syndrome (IBS) are suggested to have an altered intestinal microenvironment. We therefore aimed to determine the intestinal microenvironment profile, based on faecal microbiota and metabolites, and the potential link to symptoms in IBS patients. The faecal microbiota was evaluated by the GA-map(TM) dysbiosis test, and tandem mass spectrometry (GC-MS/MS) was used for faecal metabolomic profiling in patients with IBS and healthy subjects. Symptom severity was assessed using the IBS Severity Scoring System and anxiety and depression were assessed using the Hospital Anxiety and Depression Scale. A principal component analysis based on faecal microbiota (n = 54) and metabolites (n = 155) showed a clear separation between IBS patients (n = 40) and healthy subjects (n = 18). Metabolites were the main driver of this separation. Additionally, the intestinal microenvironment profile differed between IBS patients with constipation (n = 15) and diarrhoea (n = 11), while no clustering was detected in subgroups of patients according to symptom severity or anxiety. Furthermore, ingenuity pathway analysis predicted amino acid metabolism and several cellular and molecular functions to be altered in IBS patients. Patients with IBS have a distinct faecal microbiota and metabolite profile linked to bowel habits. Intestinal microenvironment profiling, based on faecal microbiota and metabolites, may be considered as a future non-invasive diagnostic tool, alongside providing valuable insights into the pathophysiology of IBS

Fecal Luminal Factors from Patients with Gastrointestinal Diseases Alter Gene Expression Profiles in Caco-2 Cells and Colonoids

Previous in vitro studies have shown that the intestinal luminal content, including metabolites, possibly regulates epithelial layer responses to harmful stimuli and promotes disease. Therefore, we aimed to test the hypothesis that fecal supernatants from patients with colon cancer (CC), ulcerative colitis (UC) and irritable bowel syndrome (IBS) contain distinct metabolite profiles and establish their effects on Caco-2 cells and human-derived colon organoids (colonoids). The metabolite profiles of fecal supernatants were analyzed by liquid chromatography–mass spectrometry and distinguished patients with CC (n = 6), UC (n = 6), IBS (n = 6) and healthy subjects (n = 6). Caco-2 monolayers and human apical-out colonoids underwent stimulation with fecal supernatants from different patient groups and healthy subjects. Their addition did not impair monolayer integrity, as measured by transepithelial electrical resistance; however, fecal supernatants from different patient groups and healthy subjects altered the gene expression of Caco-2 monolayers, as well as colonoid cultures. In conclusion, the stimulation of Caco-2 cells and colonoids with fecal supernatants derived from CC, UC and IBS patients altered gene expression profiles, potentially reflecting the luminal microenvironment of the fecal sample donor. This experimental approach allows for investigating the crosstalk at the gut barrier and the effects of the gut microenvironment in the pathogenesis of intestinal diseases