scholarly journals Polarization and depolarization metrics as optical markers in support to histopathology of ex vivo colon tissue

2021 ◽  
Author(s):  
Deyan Ivanov ◽  
Viktor Dremin ◽  
Ekaterina Borisova ◽  
Alexander Bykov ◽  
Tatiana Novikova ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Colon Tissue ◽  
Optical Markers

scholarly journals Design of a force-measuring setup for colorectal compression anastomosis and first ex-vivo results

2021 ◽  
Author(s):  
Jana Steger ◽  
Isabella Patzke ◽  
Maximilian Berlet ◽  
Stefanie Ficht ◽  
Markus Eblenkamp ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Tissue Fixation ◽  
Force Transmission ◽  
Tissue Thickness ◽  
Colon Tissue ◽  
Device Development ◽  
Compression Anastomosis ◽  
Technical Requirements ◽  
Significant Difference

Abstract Purpose The introduction of novel endoscopic instruments is essential to reduce trauma in visceral surgery. However, endoscopic device development is hampered by challenges in respecting the dimensional restrictions, due to the narrow access route, and by achieving adequate force transmission. As the overall goal of our research is the development of a patient adaptable, endoscopic anastomosis manipulator, biomechanical and size-related characterization of gastrointestinal organs are needed to determine technical requirements and thresholds to define functional design and load-compatible dimensioning of devices. Methods We built an experimental setup to measure colon tissue compression piercing forces. We tested 54 parameter sets, including variations of three tissue fixation configurations, three piercing body configurations (four, eight, twelve spikes) and insertion trajectories of constant velocities (5 mms−1, 10 mms−1,15 mms−1) and constant accelerations (5 mms−2, 10 mms−2, 15 mms−2) each in 5 samples. Furthermore, anatomical parameters (lumen diameter, tissue thickness) were recorded. Results There was no statistically significant difference in insertion forces neither between the trajectory groups, nor for variation of tissue fixation configurations. However, we observed a statistically significant increase in insertion forces for increasing number of spikes. The maximum mean peak forces for four, eight and twelve spikes were 6.4 ± 1.5 N, 13.6 ± 1.4 N and 21.7 ± 5.8 N, respectively. The 5th percentile of specimen lumen diameters and pierced tissue thickness were 24.1 mm and 2.8 mm, and the 95th percentiles 40.1 mm and 4.8 mm, respectively. Conclusion The setup enabled reliable biomechanical characterization of colon material, on the base of which design specifications for an endoscopic anastomosis device were derived. The axial implant closure unit must enable axial force transmission of at least 28 N (22 ± 6 N). Implant and applicator diameters must cover a range between 24 and 40 mm, and the implant gap, compressing anastomosed tissue, between 2 and 5 mm.

Luminally released serotonin stimulates colonic motility and accelerates colonic transit in rats

2007 ◽  
Vol 293 (1) ◽  
pp. R64-R69 ◽  
Author(s):  
Kiyoshi Tsukamoto ◽  
Hajime Ariga ◽  
Chris Mantyh ◽  
Theodore N. Pappas ◽  
Hidenori Yanagi ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Colonic Motility ◽  
Physiological Role ◽  
Distal Colon ◽  
Proximal Colon ◽  
Colonic Transit ◽  
Intraluminal Pressure ◽  
Ex Vivo Model ◽  
Colon Tissue ◽  
Ec Cells

Enterochromaffin (EC) cells of the epithelial cells release 5-HT into the lumen, as well as basolateral border. However, the physiological role of released 5-HT into the lumen is poorly understood. Concentrations of 5-HT in the colonic mucosa, colonic lumen, and feces were measured by HPLC in rats. To investigate whether intraluminal 5-HT accelerates colonic transit, 5-HT and 51Cr were administered into the lumen of the proximal colon, and colonic transit was measured. To investigate whether 5-HT is released into the lumen, we used an ex vivo model of isolated vascularly and luminally perfused rat proximal colon. To investigate whether luminal 5-HT is involved in regulating stress-induced colonic motility, the distal colonic motility was recorded under the stress loading, and a 5-HT3 receptor antagonist (ondansetron, 10−6 M, 0.5 ml) was administered intraluminally of the distal colon. Tissue content of 5-HT in the proximal colon (15.2 ± 4.3 ng/mg wet tissue) was significantly higher than that in the distal colon (3.3 ± 0.7 ng/mg wet tissue), while fecal content and luminal concentration of 5-HT was almost the same between the proximal and distal colon. Luminal administration of 5-HT (10−6–10−5 M) significantly accelerated colonic transit. Elevation of intraluminal pressure by 10 cmH2O significantly increased the luminal concentration of 5-HT but not the vascular concentration of 5-HT. Stress-induced stimulation of the distal colonic motility was significantly attenuated by the luminal administration of ondansetron. These results suggest that luminally released 5-HT from EC cells plays an important role in regulating colonic motility in rats.

Cold atmospheric plasma treatment inhibits growth in colorectal cancer cells

2018 ◽  
Vol 400 (1) ◽  
pp. 111-122 ◽  
Author(s):  
Christin Schneider ◽  
Stephanie Arndt ◽  
Julia L. Zimmermann ◽  
Yangfang Li ◽  
Sigrid Karrer ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Colon Cancer ◽  
Plasma Treatment ◽  
Cancer Cells ◽  
Ex Vivo ◽  
Atmospheric Plasma ◽  
Normal Colon ◽  
Colon Tissue ◽  
Cold Atmospheric Plasma ◽  
Colorectal Cancer Cells

AbstractPlasma oncology is a relatively new field of research. Recent developments have indicated that cold atmospheric plasma (CAP) technology is an interesting new therapeutic approach to cancer treatment. In this study, p53 wildtype (LoVo) and human p53 mutated (HT29 and SW480) colorectal cancer cells were treated with the miniFlatPlaSter – a device particularly developed for the treatment of tumor cells – that uses the Surface Micro Discharge (SMD) technology for plasma production in air. The present study analyzed the effects of plasma on colorectal cancer cellsin vitroand on normal colon tissueex vivo. Plasma treatment had strong effects on colon cancer cells, such as inhibition of cell proliferation, induction of cell death and modulation of p21 expression. In contrast, CAP treatment of murine colon tissueex vivofor up to 2 min did not show any toxic effect on normal colon cells compared to H2O2positive control. In summary, these results suggest that the miniFlatPlaSter plasma device is able to kill colorectal cancer cells independent of their p53 mutation status. Thus, this device presents a promising new approach in colon cancer therapy.

Quantitative analysis of mucosal oxygenation using ex vivo imaging of healthy and inflamed mammalian colon tissue

2016 ◽  
Vol 74 (1) ◽  
pp. 141-151 ◽  
Author(s):  
Alexander V. Zhdanov ◽  
Irina A. Okkelman ◽  
Anna V. Golubeva ◽  
Barbara Doerr ◽  
Niall P. Hyland ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Ex Vivo ◽  
Colon Tissue ◽  
Ex Vivo Imaging

scholarly journals Circadian misalignment by environmental light/dark shifting causes circadian disruption in colon

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0251604
Author(s):  
Laura Tran ◽  
Sarah B. Jochum ◽  
Maliha Shaikh ◽  
Sherry Wilber ◽  
Lijuan Zhang ◽  
...  
Keyword(s):  
Cell Fate ◽  
Intestinal Permeability ◽  
Barrier Function ◽  
Ex Vivo ◽  
Circadian Disruption ◽  
Luciferase Reporter ◽  
Absolute Difference ◽  
Protein Markers ◽  
Colonic Tissue ◽  
Colon Tissue

Background Physiological circadian rhythms (CRs) are complex processes with 24-hour oscillations that regulate diverse biological functions. Chronic weekly light/dark (LD) shifting (CR disruption; CRD) in mice results in colonic hyperpermeability. However, the mechanisms behind this phenomenon are incompletely understood. One potential innovative in vitro method to study colonic CRs are colon organoids. The goals of this study were to utilize circadian clock gene Per2 luciferase reporter (Per2::Luc) mice to measure the effects of chronic LD shifting on colonic tissue circadian rhythmicity ex vivo and to determine if organoids made from shifted mice colons recapitulate the in vivo phenotype. Methods Non-shifted (NS) and shifted (S) BL6 Per2::Luc mice were compared after a 22-week experiment. NS mice had a standard 12h light/12h dark LD cycle throughout. S mice alternated 12h LD patterns weekly, with light from 6am-6pm one week followed by shifting light to 6pm-6am the next week for 22 weeks. Mice were tested for intestinal permeability while colon tissue and organoids were examined for CRs of bioluminescence and proteins of barrier function and cell fate. Results There was no absolute difference in NS vs. S 24h circadian period or phase. However, chronic LD shifting caused Per2::Luc S mice colon tissue to exhibit significantly greater variability in both the period and phase of Per2::Luc rhythms than NS mice colon tissue and organoids. Chronic LD shifting also resulted in increased colonic permeability of the Per2::Luc mice as well as decreased protein markers of intestinal permeability in colonic tissue and organoids from shifted Per2:Luc mice. Conclusions Our studies support a model in which chronic central circadian disruption by LD shifting alters the circadian phenotype of the colon tissue and results in colon leakiness and loss of colonic barrier function. These CRD-related changes are stably expressed in colon stem cell derived organoids from CRD mice.

scholarly journals Oxytocin signalling in dendritic cells regulates immune tolerance in the intestine and alleviates DSS-induced colitis

2021 ◽  
Vol 135 (4) ◽  
pp. 597-611
Author(s):  
Dandan Dou ◽  
Jinghui Liang ◽  
Xiangyu Zhai ◽  
Guosheng Li ◽  
Hongjuan Wang ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Ex Vivo ◽  
Experimental Colitis ◽  
Akt Pathway ◽  
T Helper 1 ◽  
Colon Tissue ◽  
Cytokine Modulation ◽  
Inflammatory Bowel ◽  
Dc Maturation

Abstract Background: Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that is associated with immune dysfunction. Recent studies have indicated that the neurosecretory hormone oxytocin (OXT) has been proven to alleviate experimental colitis. Methods: We investigated the role of OXT/OXT receptor (OXTR) signalling in dendritic cells (DCs) using mice with specific OXTR deletion in CD11c+ cells (OXTRflox/flox×CD11c-cre mice) and a dextran sulfate sodium (DSS)-induced colitis model. Results: The level of OXT was abnormal in the serum or colon tissue of DSS-induced colitis mice or the plasma of UC patients. Both bone marrow-derived DCs (BMDCs) and lamina propria DCs (LPDCs) express OXTR. Knocking out OXTR in DCs exacerbated DSS-induced acute and chronic colitis in mice. In contrast, the injection of OXT-pretreated DCs significantly ameliorated colitis. Mechanistically, OXT prevented DC maturation through the phosphatidylinositol 4,5-bisphosphate 3-kinase (Pi3K)/AKT pathway and promoted phagocytosis, adhesion and cytokine modulation in DCs. Furthermore, OXT pre-treated DCs prevent CD4+ T cells differentiation to T helper 1 (Th1) and Th17. Conclusions: Our results suggest that OXT-induced tolerogenic DCs efficiently protect against experimental colitis via Pi3K/AKT pathway. Our work provides evidence that the nervous system participates in the immune regulation of colitis by modulating DCs. Our findings suggest that generating ex vivo DCs pretreated with OXT opens new therapeutic perspectives for the treatment of UC in humans.

Neutralization of interleukin-18 reduces severity in murine colitis and intestinal IFN-γ and TNF-α production

2001 ◽  
Vol 281 (4) ◽  
pp. R1264-R1273 ◽  
Author(s):  
Britta Siegmund ◽  
Giamila Fantuzzi ◽  
Florian Rieder ◽  
Fabia Gamboni-Robertson ◽  
Hans-Anton Lehr ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Intestinal Inflammation ◽  
Ex Vivo ◽  
Experimental Colitis ◽  
Suppressive Effect ◽  
Confocal Laser ◽  
Colon Tissue ◽  
Lamina Propria Mononuclear Cells ◽  
Ifn Γ

Interleukin (IL)-18, initially described as interferon (IFN)-γ-inducing factor, is expressed in the inflamed mucosa of patients with Crohn's disease. To investigate the role of IL-18 in intestinal inflammation, the effect of neutralizing antimurine IL-18 antiserum in dextran sulfate sodium (DSS)-induced colitis in BALB/c and C57BL/6 mice was examined. During a dose response of DSS, levels of colonic IL-18 increased parallel with clinical worsening. With the use of confocal laser microscopy, the increased IL-18 was localized to the intestinal epithelial layer. Anti-IL-18 treatment resulted in a dose-dependent reduction of the severity of colitis in both BALB/c and C57BL/6 mice. Colon shortening following DSS-induced colitis was partially prevented in the treatment groups. In the colon tissue homogenates, IFN-γ concentrations were lower in the anti-IL-18-treated DSS-fed mice compared with untreated DSS-fed mice. This suppressive effect of anti-IL-18 administered in vivo was also observed on spontaneous tumor necrosis factor-α, IL-18, and IFN-γ production from ex vivo colon organ cultures. The stimulation of lamina propria mononuclear cells by IL-18 and IL-12 resulted in a synergistic increase in IFN-γ synthesis. These findings suggest that IL-18 is a pivotal mediator in experimental colitis.

scholarly journals Mycoplasma hyopneumoniae–Lawsonia intracellularis dual challenge modulates intestinal integrity and function1

2019 ◽  
Vol 97 (6) ◽  
pp. 2376-2384 ◽  
Author(s):  
Emma T Helm ◽  
Shelby M Curry ◽  
Kent J Schwartz ◽  
Steven M Lonergan ◽  
Nicholas K Gabler
Keyword(s):  
Ex Vivo ◽  
Digestive Enzyme ◽  
Random Effect ◽  
Mycoplasma Hyopneumoniae ◽  
Intestinal Function ◽  
Lawsonia Intracellularis ◽  
Colon Tissue ◽  
Transport Barrier ◽  
Ussing Chambers ◽  
Pig Performance

Abstract Lawsonia intracellularis (LI) and Mycoplasma hyopneumoniae (Mh) are 2 globally distributed pathogens that cause significant morbidity and mortality in grow-finish pigs. However, mechanisms that reduce growth and feed efficiency during LI and Mh infection are poorly defined. We hypothesized that reductions in performance are partially due to declines in intestinal function and integrity; thus, this study aimed to evaluate intestinal function and integrity of pigs during a 21-d Mh and LI dual challenge (MhLI). Littermate pairs of barrows (48.1 ± 6.7 kg BW) were selected; 1 pig from each pair was assigned to either MhLI challenge or nonchallenge treatments (n = 12). Pigs were individually housed, fed a corn-soybean diet, and allowed to acclimate for 21 d prior to inoculation. On days postinoculation (dpi) 0, MhLI pigs were dual inoculated with LI and Mh. On dpi 21, all pigs were euthanized for ileal and colon tissue collection. Formalin-fixed tissues were clinically scored and morphology analyzed, frozen tissues assayed for digestive enzyme activities, and fresh tissues mounted into modified Ussing Chambers to assess active nutrient transport, barrier integrity, and bacterial translocation. Data were analyzed using the Mixed Procedure of SAS with treatment as a fixed effect, age and start BW as covariates, and litter as a random effect. Compared with controls, MhLI pigs had decreased ADG (38%, P < 0.001), ADFI (25%, P < 0.001), and G:F (19%, P = 0.012). The MhLI dual challenge did not alter ileum morphology or transepithelial resistance (P > 0.10); however, ex vivo mucosal to serosal translocation of S. Typhimurium in the colon was increased (60%, P = 0.003) in MhLI pigs compared with controls. Additionally, MhLI pigs had increased ileal glucose transport (30%, P = 0.05) and decreased sucrase activity (30%, P = 0.049) compared with controls. This MhLI challenge antagonized intestinal function and integrity, and this may be a contributing factor to reduced pig performance.

scholarly journals Ex Vivo Human Colon Tissue Exposure to Pristine Graphene Activates Genes Involved in the Binding, Adhesion and Proliferation of Epithelial Cells

2021 ◽  
Vol 22 (21) ◽  
pp. 11443
Author(s):  
Mohamed H. Lahiani ◽  
Kuppan Gokulan ◽  
Katherine Williams ◽  
Sangeeta Khare
Keyword(s):  
Ex Vivo ◽  
Biological Response ◽  
Human Colon ◽  
Nuclear Antigen ◽  
Pristine Graphene ◽  
Colon Tissue ◽  
Healthy Human ◽  
Vegf Signaling ◽  
Proliferating Cell ◽  
Pro Inflammatory Cytokines

Toxicology studies on pristine graphene are limited and lack significant correlations with actual human response. The goal of the current study was to determine the response of total colonic human tissue to pristine graphene exposure. Biopsy punches of colon tissues from healthy human were used to assess the biological response after ex vivo exposure to graphene at three different concentrations (1, 10, and 100 µg/mL). mRNA expression of specific genes or intestinal cytokine abundance was assessed using real-time PCR or multiplex immunoassays, respectively. Pristine graphene-activated genes that are related to binding and adhesion (GTPase and KRAS) within 2 h of exposure. Furthermore, the PCNA (proliferating cell nuclear antigen) gene was upregulated after exposure to graphene at all concentrations. Ingenuity pathway analysis revealed that STAT3 and VEGF signaling pathways (known to be involved in cell proliferation and growth) were upregulated. Graphene exposure (10 µg/mL) for 24 h significantly increased levels of pro-inflammatory cytokines IFNγ, IL-8, IL-17, IL-6, IL-9, MIP-1α, and Eotaxin. Collectively, these results indicated that graphene may activate the STAT3–IL23–IL17 response axis. The findings in this study provide information on toxicity evaluation using a human-relevant ex vivo colon model and serve as a basis for further exploration of its bio-applications.

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