Fanconi anemia complementation group D2 promotes sensitivity of endometrial cancer cells to chemotherapeutic agents by inhibiting the ferroptosis pathway.

BACKGROUND: Resistance can develop during treatment of advanced endometrial cancer (EC), leading to unsatisfactory results. Fanconi anemia complementation group D2 (Fancd2) has been shown to be closely related to drug resistance in cancer cells. Therefore, this study was designed to explore the correlation of Fancd2 with EC resistance and the mechanism of Fancd2. METHODS: Real-time quantitative PCR (RT-qPCR) was used to detect the expression of Fancd2 in EC tissues and cells. EC cells (Ishikawa) and paclitaxel-resistant EC cells (Ishikawa/TAX) were transfected to knock down Fancd2. In addition, the ferroptosis inhibitor Ferrostatin-1 was adopted to treat Ishikawa/TAX cells. The sensitivity of cancer cells to chemotherapeutic agents was observed via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and inhibitory concentration (IC)50 was calculated. Reactive oxygen species (ROS) levels were measured by flow cytometry, the activity of malondialdehyde (MDA) and the levels of glutathione (GSH) and Fe2+ in cells were detected by corresponding kits, and protein expression of solute farrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) was obtained through western blot. RESULTS: Compared with the normal tissues and endometrial epithelial cells, Fancd2 expression was significantly increased in EC tissues and Ishikawa cells, respectively. After knock-down of Fancd2, Ishikawa cells showed significantly increased sensitivity to chemotherapeutic agents. Besides, compared with Ishikawa cells, the levels of ROS, the activity of MDA, and the levels of GSH and Fe2+ were significantly decreased in Ishikawa/TAX cells, while the expression levels of SLC7A11 and GPX4 were significantly increased. Knock-down of Fancd2 significantly increased the ferroptosis levels in Ishikawa/TAX cells, but this effect could be reversed by Ferrostatin-1. CONCLUSION: Fancd2 increases drug resistance in EC cells by inhibiting the cellular ferroptosis pathway.

Comparison of the efficacy and safety of total laparoscopic hysterectomy without and with uterine manipulator combined with pelvic lymphadenectomy for early cervical cancer.

OBJECTIVE: Some studies have reported that the prognosis of total laparoscopic hysterectomy (TLH) for early-stage cervical cancer (CC) is worse than that of open surgery. And this was associated with the use of uterine manipulator or not. Therefore, this study retrospectively analyzes the efficacy and safety of TLH without uterine manipulator combined with pelvic lymphadenectomy for early-stage CC. METHODS: Fifty-eight patients with CC (stage IB1-IIA1) who received radical hysterectomy from September 2019 to January 2020 were divided into no uterine manipulator (n = 26) and uterine manipulator group (n = 32). Then, clinical characteristics were collected and intraoperative/postoperative related indicators were compared. RESULTS: Patients in the no uterine manipulator group had significantly higher operation time and blood loss than in the uterine manipulator group. Notably, there was no significant difference in hemoglobin change, blood transfusion rate, number of pelvic nodules, anal exhaust time, complications and recurrence rate between the two groups. Additionally, patients in the uterine manipulator group were prone to urinary retention (15.6%) and lymphocyst (12.5%), while the no uterine manipulator group exhibited high probability of bladder dysfunction (23.1%) and urinary retention (15.4%). Furthermore, the 1-year disease-free survival rate and the 1-year overall survival rate were not significantly different between the two groups. CONCLUSION: There was no significant difference in the efficacy and safety of TLH with or without uterine manipulator combined with pelvic lymphadenectomy in the treatment of patients with early-stage CC. However, the latter requires consideration of the negative effects of high operation time and blood loss.

Effect of Helicobacter pylori Eradication Therapy on the Incidence of Noncardia Gastric Adenocarcinoma in a Large Diverse Population in the United States.

BACKGROUND & AIMS: High-quality data regarding the effect of Helicobacter pylori eradication on the risk of noncardia gastric adenocarcinoma (NCGA) remain limited in the United States. We investigated the incidence of NCGA after H pylori eradication therapy in a large, community-based US population. METHODS: We performed a retrospective cohort study of Kaiser Permanente Northern California members who underwent testing and/or treatment for H pylori between 1997 and 2015 and were followed through December 31, 2018. The risk of NCGA was evaluated using the Fine-Gray subdistribution hazard model and standardized incidence ratios. RESULTS: Among 716,567 individuals with a history of H pylori testing and/or treatment, the adjusted subdistribution hazard ratios and 95% confidence intervals of NCGA for H pylori-positive/untreated and H pylori-positive/treated individuals were 6.07 (4.20-8.76) and 2.68 (1.86-3.86), respectively, compared with H pylori-negative individuals. When compared directly with H pylori-positive/untreated individuals, subdistribution hazard ratios for NCGA in H pylori-positive/treated were 0.95 (0.47-1.92) at <8 years and 0.37 (0.14-0.97) ≥8 years of follow-up. Compared with the Kaiser Permanente Northern California general population, standardized incidence ratios (95% confidence interval) of NCGA steadily decreased after H pylori treatment: 2.00 (1.79-2.24) ≥1 year, 1.01 (0.85-1.19) ≥4 years, 0.68 (0.54-0.85) ≥7 years, and 0.51 (0.38-0.68) ≥10 years. CONCLUSION: In a large, diverse, community-based population, H pylori eradication therapy was associated with a significantly reduced incidence of NCGA after 8 years compared with no treatment. The risk among treated individuals became lower than the general population after 7 to 10 years of follow-up. The findings support the potential for substantial gastric cancer prevention in the United States through H pylori eradication.

The exposure to television advertising of unhealthy food among children and adolescents and its impact in Beijing / 中国学校卫生

Objective@#To examine the exposure to television advertising of unhealthy food among children and adolescents in Beijing, in order to provide a basis for the formulation of marketing management policies with unhealthy food.@*Methods@#Four weekdays and four weekend days were randomly selected during October 19, 2020 to January 17, 2021, excluding holidays and school holidays. The top five popular channels of children and adolescents aged 3 to 18 years old were selected. A total of 720 hours was included for coding and analysis. World Health Organization Nutrient Profile Model for the Western Pacific Region was used to classify food and assess the health level.@*Results@#A total of 13 864 advertisings (ads) was monitored, 38.8% (5 376) of which were food ads. Furthermore, 49.9% (2 680) of food ads were unhealthy food ads, with a frequency of 2.00 per hour per channel. The top five most frequent food ads were infant formula for 12-36 months (26.7%), cheese (16.7%), savory snacks (12.2%), milk drinks (10.5%) and chocolate and candy (6.0%). The most frequently used marketing strategies for unhealthy food ads were brand benefit claims (96.8%) and promotional characters (67.9%).@*Conclusion@#Children and adolescents in Beijing are highly exposed to TV marketing of unhealthy foods. Marketing strategies such as brand benefit claims and promotional characters are employed to boost the impact of unhealthy food ads. There is an urgent need to introduce relevant policies to regulate TV marketing of unhealthy foods.

The extent and nature of television food and non-alcoholic beverage advertising to children during chinese New Year in Beijing, China.

BACKGROUND: Exposure to food and non-alcoholic beverage advertisements (F&B ads) on television, which can affect children's nutrition knowledge, food consumption, diet quality, and purchasing preferences, is one aspect of the obesogenic environment. This aspect has been well-studied and assessed in many countries. In China, however, only few studies have been done in earlier years and all of them were focus on regular days. This study aimed to assess the extent and nature of F&B ads on television (TV) during the public holiday directed towards children aged 4-14 years in Beijing. METHOD: Top 3 channels viewed by children aged 4-14 years in Beijing were selected by TV viewership data, survey, and expert consultation. Each channel was recorded for 7 days (24 h) during the public holiday of the Chinese New Year in 2019. F&B ads were coded and analyzed following the adapted food promotion module of INFORMAS protocol. Three nutrient profile models were used to classify F&B ads as healthy or unhealthy F&B ads. RESULTS: Of the 10,082 ads in 504-hour recorded programs, 42.9% were F&B ads. The hourly average ads and F&B ads per channel were 19.8 (SD 15.32) and 8.6 (SD 9.84), while that was higher on the national children's channel (17.15, SD 12.25) than other channels (p < 0.05). Of F&B ads classified with the three nutrient profile models, more than 55% were unhealthy for children. The categories most frequently advertised were savory snacks, milk drinks, nonpermitted milk drinks, cakes/sweet biscuits, and beverages. Unhealthy F&B ads were more likely to use promotional characters, brand benefit claims, and health claims than permitted F&B ads (p < 0.05). CONCLUSIONS: Children in Beijing were exposed to a high proportion of unhealthy F&B ads during the Chinese New Year holiday. Our findings support the need to assess and regulate TV F&B ads marketing for children.

Risk stratification for colorectal cancer in individuals with subtypes of serrated polyps.

OBJECTIVE: The longitudinal risk of colorectal cancer (CRC) associated with subtypes of serrated polyps (SPs) remains incompletely understood. DESIGN: This community-based, case-control study included 317 178 Kaiser Permanente Northern California members who underwent their first colonoscopy during 2006-2016. Nested within this population, we identified 695 cases of CRC and 3475 CRC-free controls (matched 5:1 to cases for age, sex and year of colonoscopy). Two expert pathologists reviewed the tissue slides of all SPs identified on the first colonoscopy and reclassified them to sessile serrated lesions (SSLs), hyperplastic polyps (HPs) and traditional serrated adenomas. SPs with borderline characteristics of SSLs but insufficient to make a definitive diagnosis were categorised as unspecified SPs. The association with development of CRC was assessed using multivariable logistic regression. RESULTS: Compared with individuals with no polyp, the adjusted ORs (aORs) for SSL alone or with synchronous adenoma were 2.9 (95% CI: 1.8 to 4.8) and 4.4 (95% CI: 2.7 to 7.2), respectively. The aORs for SSL with dysplasia, large proximal SSL,and small proximal SSL were 10.3 (95% CI: 2.1 to 50.3), 12.8 (95% CI: 3.5 to 46.9) and 1.9 (95% CI: 0.8 to 4.7), respectively. Proximal unspecified SP also conferred an increased risk (aOR: 5.8, 95% CI: 2.2 to 15.2). Women with SSL were associated with higher risk (aOR: 4.4; 95% CI: 2.3 to 8.2) than men (aOR: 1.7; 95% CI: 0.8 to 3.8). CONCLUSION: Increased risk of CRC was observed in individuals with SSLs, particularly large proximal ones or with dysplasia, supporting close endoscopic surveillance. Proximal unspecified SPs were also associated with increased risk of CRC and should be managed as SSLs.

Analysis of serum 25 hydroxyvitamin D levels in children aged 0-6 years in Gansu Province / 中国学校卫生

Objective@#To analyze the status of serum 25 hydroxyvitamin D[25 (OH)D] in children aged 0-6 years in Gansu Province, and to analyze the relationships between 25 (OH)D and age, seasonal characteristics and physical development, so as to provide a scientific reference for supplementing vitamin D for children in due time.@*Methods@#Stratified random cluster sampling method was used to select a total of 9 790 children aged 0-6 years from 6 cities and prefectures maternity and child health institutions in Gansu Province for health examination from January 2019 to December 2020. Serum 25 (OH)D concentration from 1 mL peripheral blood was tested by enzyme linked immunoassay. Subjects were classified into overweight and normal figure groups based on weight for height.@*Results@#the serum 25 (OH)D level M(P 25 ,P 75 ) of the children aged 0-6 was 81.31(63.14, 95.86)nmol/L. The detection rate of 25 (OH)D deficiency and insufficiency was 45.11%. The serum 25 (OH)D level of children 4- 6 years old was significantly lower than that of infants <1 year old and children 1-<4 years old, and the detection rate of 25 (OH)D deficiency and insufficiency was highest among 4-6 years old( χ 2=83.67, P <0.05). In winter the proportion of 25 (OH)D insufficiency and deficiency was highest (55.82%) ( χ 2=194.12, P <0.01). For overweight children, the abnormal rate of 25 (OH)D (19.83%) was significantly higher in autumn ( P <0.01).@*Conclusion@#Children s vitamin D levels were associated with age, season and physical development. Vitamin D surveillance should be focused on ages less than 1 year old and above 4 years old, winter should be an important season. For overweight children, autumn should be the focus period for vitamin D deficiency prevention.

Comparison of Surgical and Cadaveric Intestine as a Source of Crypt Culture in Humans.

Human small intestinal crypts are the source of intestinal stem cells (ISCs) that are capable of undergoing self-renewal and differentiation to an epithelial layer. The development of methods to expand the ISCs has provided opportunities to model human intestinal epithelial disorders. Human crypt samples are usually obtained from either endoscopic or discarded surgical samples, and are thereby exposed to warm ischemia, which may impair their in vitro growth as three-dimensional culture as spheroids or enteroids. In this study we compared duodenal samples obtained from discarded surgical samples to those isolated from whole-body preserved cadaveric donors to generate in vitro cultures. We also examined the effect of storage solution (phosphate-buffered saline or University of Wisconsin [UW] solution) as well as multiple storage times on crypt isolation and growth in culture. We found that intestinal crypts were successfully isolated from cadaveric tissue stored for up to 144 h post-procurement and also were able to generate enteroids and spheroids in certain media conditions. Surgical samples stored in UW after procurement were sufficiently viable up to 24 h and also allowed the generation of enteroids and spheroids. We conclude that surgical samples stored for up to 24 h post-procurement in UW solution allowed for delayed crypt isolation and viable in vitro cultures. Furthermore, in situ, hypothermic preservation in cadaveric duodenal samples permitted crypt/ISC isolation, and successful culture of spheroids and enteroids from tissues held for up to 6 days post-procurement.

[Inhibition of scutellarin on differentiation of colonic cancer stem cells via hedgehog signaling pathway].

The objective of this study was to investigate the inhibitory effect of scutellarin on the differentiation of colonic cancer stem cells in vitro and in vivo and to explore its underlying hedgehog signaling-based mechanism. The effect of scutellarin on the growth in vitro of HT-29 cells-derived cancer stem-like cells(HT-29 CSC) was observed with 3 D cell culture. The effect of scutellarin on the transformation of HT-29 CSC cells was assessed by soft agar colony formation assay. Fetal calf serum was used to induce differentiation of stem cells and observe the effect of scutellarin on HT-29 CSC cells differentiation in vitro. The effects of scutellarin on mRNA expressions of Lgr5, c-Myc, CK20 and Nanog in HT-29 CSC cells were determined by quantitative Real-time polymerase chain reaction(qRT-PCR). The effects of scutellarin on protein expressions of c-Myc, Gli1 and Lgr5 in HT-29 CSC cells were examined by Western blot. After subcutaneous implantation of HT-29 CSC cells in nude mice, the effect of scutellarin on the mouse body weight and the growth of HT-29 CSC-derived tumor were explored. qRT-PCR was used for evaluating the effect of scutellarin on mRNA levels of CD133, Lgr5, Gli1, Ptch1, c-Myc, Ki-67, CK20 and Nanog in tumor. Western blot and immunohistochemistry analysis were used to detect the effect of scutellarin on protein expressions of c-Myc, Gli1, Lgr5, CD133 and Ki-67 in tumor. The in vitro experiments showed that scutellarin inhibited the growth, transformation and differentiation of HT-29 CSC cells, significantly down-regulated the mRNA levels of Lgr5, c-Myc, CK20 and Nanog in HT-29 CSC cells as well as the protein expression levels of c-Myc, Gli1 and Lgr5 in HT-29 CSC cells. Additionally, animal experiments showed that scutellarin significantly inhibited the growth of subcutaneous xenografts in nude mice, and down-regulated the mRNA expressions of CD133, Lgr5, Gli1, Ptch1, c-Myc, Ki-67, CK20 and Nanog as well as the protein levels of c-Myc, Gli1, Lgr5, CD133 and Ki-67 of xenografts in nude mice. Taken together, scutellarin could inhibit the differentiation of colo-nic cancer stem cells in vitro and in vivo, potentially by down regulation of hedgehog signaling pathway activity.

Bioengineering functional smooth muscle with spontaneous rhythmic contraction in vitro.

Oriented smooth muscle layers in the intestine contract rhythmically due to the action of interstitial cells of Cajal (ICC) that serve as pacemakers of the intestine. Disruption of ICC networks has been reported in various intestinal motility disorders, which limit the quality and expectancy of life. A significant challenge in intestinal smooth muscle engineering is the rapid loss of function in cultured ICC and smooth muscle cells (SMC). Here we demonstrate a novel approach to maintain the function of both ICC and SMC in vitro. Primary intestinal SMC mixtures cultured on feeder cells seeded electrospun poly(3-caprolactone) scaffolds exhibited rhythmic contractions with directionality for over 10 weeks in vitro. The simplicity of this system should allow for wide usage in research on intestinal motility disorders and tissue engineering, and may prove to be a versatile platform for generating other types of functional SMC in vitro.

Association Between Oxidative Stress and Peripheral Leukocyte Telomere Length in Patients with Premature Coronary Artery Disease.

BACKGROUND Leukocyte telomere length (LTL) is regarded as a potential marker of biological aging. Oxidative stress plays a major role in the rate of telomeric DNA loss. The aim of this study was to explore whether the LTL was shorter in Chinese patients with premature coronary artery disease (PCAD) than in non-CAD controls and to determine the relationship between oxidative stress and LTL shortening in this population. MATERIAL AND METHODS Patients for coronary angiography were recruited. In total, 128 patients with PCAD and 128 non-CAD controls were enrolled. Samples of circulating leukocytes and plasma were collected. The mean LTL was measured using a polymerase chain reaction-based assay and expressed as the ratio of telomere repeat copies to single-copy gene (SCG) copies (T/S ratio). Reactive oxygen species (ROS) levels and total antioxidant capacity (T-AOC) were determined in plasma. RESULTS Both the T/S ratio (0.88±0.86 vs. 1.10±0.57, P=0.015) and telomere base pairs (4.97±1.37 kb vs. 5.32±0.91 kb, P=0.015) were significantly shorter in the PCAD group than in non-CAD controls. The T-AOC levels of the PCAD group were significantly lower than those of the non-CAD controls (0.482 mM [0.279, 0.603 mM]) vs. 0.778 mM [0.421, 0.924 mM], P=0.000). The ratio of T-AOC to ROS in the PCAD patients was significantly decreased compared to that of the non-CAD controls (0.1026±0. 1587 [Mm*ml/ng] vs. 0.1435±0.1946 [Mm*ml/ng], P=0.013). CONCLUSIONS The results point to a potential link between reduced LTLs in patients with PCAD and early onset of atherosclerosis. The decline in antioxidant capacity may play an important role in accelerating the attrition of telomeres in PCAD patients.

Incidence and risk factors of new foot ulcer among diabetic patients on peritoneal dialysis / 中华肾脏病杂志

Objective To study the incidence and risk factors of new foot ulcer among diabetic patients on peritoneal dialysis.Methods This is a single-center prospective cohort study.Clinically-stable diabetic patients on peritoneal dialysis in our renal division were recruited from January 2014 to June 2014.Baseline data including general information,biochemistry data,dialysis adequacy,the dorsalis pedis artery pulse,clinical symptoms of diabetic foot and ankle brachial index were recorded.All patients were followed till to Dec 31,2015.The outcomes consisted of new foot ulcer,amputation due to foot ulcer or gangrene,and lower limb vascular blood supply revascularization.Results Totally 108 patients were recruited and followed up the average time (17.7±5.6) months.Among 108 patients,16 cases had a history of diabetic foot ulcer,and 1 case had amputation.During the follow-up,11 cases (10.2％) had new foot ulcer,3 cases (2.8％) had amputation due to foot ulcers or gangrene,and 8 cases (7.4％) had lower limb vascular blood supply revascularization.A total of 13 cases (12％) had composite end points with 81.3 times/1000 patients of incidence.Univariate and multivariate Cox regression models showed that the history of foot ulcer was the only independent risk factors for new foot ulcers-related composite end points.Conclusion The incidence of new foot ulcer-related composite end points was 12％,which could be independently predicted by the history of diabetic foot ulcer.

Incidence and risk factors of new foot ulcer among diabetic patients on peritoneal dialysis / 中华肾脏病杂志

Objective To study the incidence and risk factors of new foot ulcer among diabetic patients on peritoneal dialysis.Methods This is a single-center prospective cohort study.Clinically-stable diabetic patients on peritoneal dialysis in our renal division were recruited from January 2014 to June 2014.Baseline data including general information,biochemistry data,dialysis adequacy,the dorsalis pedis artery pulse,clinical symptoms of diabetic foot and ankle brachial index were recorded.All patients were followed till to Dec 31,2015.The outcomes consisted of new foot ulcer,amputation due to foot ulcer or gangrene,and lower limb vascular blood supply revascularization.Results Totally 108 patients were recruited and followed up the average time (17.7±5.6) months.Among 108 patients,16 cases had a history of diabetic foot ulcer,and 1 case had amputation.During the follow-up,11 cases (10.2％) had new foot ulcer,3 cases (2.8％) had amputation due to foot ulcers or gangrene,and 8 cases (7.4％) had lower limb vascular blood supply revascularization.A total of 13 cases (12％) had composite end points with 81.3 times/1000 patients of incidence.Univariate and multivariate Cox regression models showed that the history of foot ulcer was the only independent risk factors for new foot ulcers-related composite end points.Conclusion The incidence of new foot ulcer-related composite end points was 12％,which could be independently predicted by the history of diabetic foot ulcer.

A novel culture system for adult porcine intestinal crypts.

Porcine models are useful for investigating therapeutic approaches to short bowel syndrome and potentially to intestinal stem cell (ISC) transplantation. Whereas techniques for the culture and genetic manipulation of ISCs from mice and humans are well established, similar methods for porcine stem cells have not been reported. Jejunal crypts were isolated from murine, human, and juvenile and adult porcine small intestine, suspended in Matrigel, and co-cultured with syngeneic intestinal subepithelial myofibroblasts (ISEMFs) or cultured without feeder cells in various culture media. Media containing epidermal growth factor, noggin, and R-spondin 1 (ENR medium) were supplemented with various combinations of Wnt3a- or ISEMF-conditioned medium (CM) and with glycogen synthase kinase 3 inhibitor (GSK3i), and their effects were studied on cultured crypts. Cell lineage differentiation was assessed by immunohistochemistry and quantitative polymerase chain reaction. Cultured porcine cells were serially passaged and transduced with a lentiviral vector. Whereas ENR medium supported murine enteroid growth, it did not sustain porcine crypts beyond 5 days. Supplementation of Wnt3a-CM and GSK3i resulted in the formation of complex porcine enteroids with budding extensions. These enteroids contained a mixture of stem and differentiated cells and were successfully passaged in the presence of GSK3i. Crypts grown in media supplemented with porcine ISEMF-CM formed spheroids that were less well differentiated than enteroids. Enteroids and spheroids were transfected with a lentivirus with high efficiency. Thus, our method maintains juvenile and adult porcine crypt cells long-term in culture. Porcine enteroids and spheroids can be successfully passaged and transduced by using lentiviral vectors.

Development of Functional Microfold (M) Cells from Intestinal Stem Cells in Primary Human Enteroids.

BACKGROUND & AIMS: Intestinal microfold (M) cells are specialized epithelial cells that act as gatekeepers of luminal antigens in the intestinal tract. They play a critical role in the intestinal mucosal immune response through transport of viruses, bacteria and other particles and antigens across the epithelium to immune cells within Peyer's patch regions and other mucosal sites. Recent studies in mice have demonstrated that M cells are generated from Lgr5+ intestinal stem cells (ISCs), and that infection with Salmonella enterica serovar Typhimurium increases M cell formation. However, it is not known whether and how these findings apply to primary human small intestinal epithelium propagated in an in vitro setting. METHODS: Human intestinal crypts were grown as monolayers with growth factors and treated with recombinant RANKL, and assessed for mRNA transcripts, immunofluorescence and uptake of microparticles and S. Typhimurium. RESULTS: Functional M cells were generated by short-term culture of freshly isolated human intestinal crypts in a dose- and time-dependent fashion. RANKL stimulation of the monolayer cultures caused dramatic induction of the M cell-specific markers, SPIB, and Glycoprotein-2 (GP2) in a process primed by canonical WNT signaling. Confocal microscopy demonstrated a pseudopod phenotype of GP2-positive M cells that preferentially take up microparticles. Furthermore, infection of the M cell-enriched cultures with the M cell-tropic enteric pathogen, S. Typhimurium, led to preferential association of the bacteria with M cells, particularly at lower inoculum sizes. Larger inocula caused rapid induction of M cells. CONCLUSIONS: Human intestinal crypts containing ISCs can be cultured and differentiate into an epithelial layer with functional M cells with characteristic morphological and functional properties. This study is the first to demonstrate that M cells can be induced to form from primary human intestinal epithelium, and that S. Typhimurium preferentially infect these cells in an in vitro setting. We anticipate that this model can be used to generate large numbers of M cells for further functional studies of these key cells of intestinal immune induction and their impact on controlling enteric pathogens and the intestinal microbiome.

Elemental step thermodynamics of various analogues of indazolium alkaloids to obtaining hydride in acetonitrile.

A series of analogues of indazolium alkaloids were designed and synthesized. The thermodynamic driving forces of the 6 elemental steps for the analogues of indazolium alkaloids to obtain hydride in acetonitrile were determined using an isothermal titration calorimeter (ITC) and electrochemical methods, respectively. The effects of molecular structure and substituents on the thermodynamic driving forces of the 6 steps were examined. Meanwhile, the oxidation mechanism of NADH coenzyme by indazolium alkaloids was examined using the chemical mimic method. The result shows that the oxidation of NADH coenzyme by indazolium alkaloids in vivo takes place by one-step concerted hydride transfer mechanism.

Primary Myofibroblasts Maintain Short-Term Viability following Submucosal Injection in Syngeneic, Immune-Competent Mice Utilizing Murine Colonoscopy.

The myofibroblast is an important stromal cell of the gastrointestinal tract. Current in vitro and in vivo models either do not accurately recreate stromal-epithelial interactions or are not specific to myofibroblasts. We sought to create an animal model that would allow the study of myofibroblast-epithelial interactions. We isolated and cultured colonic myofibroblasts from FVB mice. Cells were α-SMA and vimentin positive but desmin negative on immunoblot analysis. We injected the myofibroblasts into the colonic submucosa of syngeneic adult mice (n = 8) via a miniendoscopic system. We then isolated green fluorescent protein (GFP) positive colonic myofibroblasts from C57BL/6-Tg(CAG-EGFP)1Osb/J mice and injected them into the colonic lamina propria of C57BL/6J mice at 1x10(5) (n = 14), 1x10(6) (n = 9), or 5x10(6) cells/mL (n = 4). A subset of mice were injected with serum-free media and ink without cells (n = 3). Mice underwent repeat endoscopy and euthanasia one or 7 days after injection. Colons were isolated and either fixed in 10% formalin or the inked sites were individually excised and lysed for DNA. We assessed the injection sites via histology and immunohistochemical stains for α-SMA and GFP. We used qPCR to quantify GFP DNA transcripts at the lamina propria injection sites. Submucosal injection of myofibroblasts resulted in the formation of a subepithelial wheal on endoscopy, which persisted to day 7. Myofibroblasts injected either into the submucosa or lamina propria maintained viability on post-injection day 7 as evidenced by positive α-SMA staining. qPCR of lamina propria injections showed a dose-dependent increase in GFP DNA transcripts on post-injection day 1, whereas the number of transcripts on day 7 was equivalent for the concentrations injected. We demonstrate short-term survival of primary cultured colonic myofibroblasts in syngeneic mice. This may prove to be a valuable model for studying the role of myofibroblasts in states of health and disease.

Orthogonally oriented scaffolds with aligned fibers for engineering intestinal smooth muscle.

Controlling cellular alignment is critical in engineering intestines with desired structure and function. Although previous studies have examined the directional alignment of cells on the surface (x-y plane) of parallel fibers, quantitative analysis of the cellular alignment inside implanted scaffolds with oriented fibers has not been reported. This study examined the cellular alignment in the x-z and y-z planes of scaffolds made with two layers of orthogonally oriented fibers. The cellular orientation inside implanted scaffolds was evaluated with immunofluorescence. Quantitative analysis of coherency between cell orientation and fiber direction confirmed that cells aligned along the fibers not only on the surface (x-y plane) but also inside the scaffolds (x-z & y-z planes). Our study demonstrated that two layers of orthogonally aligned scaffolds can generate the histological organization of cells similar to that of intestinal circular and longitudinal smooth muscle.

Type I collagen as an extracellular matrix for the in vitro growth of human small intestinal epithelium.

BACKGROUND: We previously reported in vitro maintenance and proliferation of human small intestinal epithelium using Matrigel, a proprietary basement membrane product. There are concerns over the applicability of Matrigel-based methods for future human therapies. We investigated type I collagen as an alternative for the culture of human intestinal epithelial cells. METHODS: Human small intestine was procured from fresh surgical pathology specimens. Small intestinal crypts were isolated using EDTA chelation. Intestinal subepithelial myofibroblasts were isolated from a pediatric sample and expanded in vitro. After suspension in Matrigel or type I collagen gel, crypts were co-cultured above a confluent layer of myofibroblasts. Crypts were also grown in monoculture with exposure to myofibroblast conditioned media; these were subsequently sub-cultured in vitro and expanded with a 1∶2 split ratio. Cultures were assessed with light microscopy, RT-PCR, histology, and immunohistochemistry. RESULTS: Collagen supported viable human epithelium in vitro for at least one month in primary culture. Sub-cultured epithelium expanded through 12 passages over 60 days. Histologic sections revealed polarized columnar cells, with apical brush borders and basolaterally located nuclei. Collagen-based cultures gave rise to monolayer epithelial sheets at the gel-liquid interface, which were not observed with Matrigel. Immunohistochemical staining identified markers of differentiated intestinal epithelium and myofibroblasts. RT-PCR demonstrated expression of α-smooth muscle actin and vimentin in myofibroblasts and E-Cadherin, CDX2, villin 1, intestinal alkaline phosphatase, chromogranin A, lysozyme, and Lgr5 in epithelial cells. These markers were maintained through several passages. CONCLUSION: Type I collagen gel supports long-term in vitro maintenance and expansion of fully elaborated human intestinal epithelium. Collagen-based methods yield familiar enteroid structures as well as a new pattern of sheet-like growth, and they eliminate the need for Matrigel for in vitro human intestinal epithelial growth. Future research is required to further develop this cell culture system for tissue engineering applications.

Intestinal subepithelial myofibroblasts support the growth of intestinal epithelial stem cells.

Intestinal epithelial stem cells (ISCs) are the focus of recent intense study. Current in vitro models rely on supplementation with the Wnt agonist R-spondin1 to support robust growth, ISC self-renewal, and differentiation. Intestinal subepithelial myofibroblasts (ISEMFs) are important supportive cells within the ISC niche. We hypothesized that co-culture with ISEMF enhances the growth of ISCs in vitro and allows for their successful in vivo implantation and engraftment. ISC-containing small intestinal crypts, FACS-sorted single ISCs, and ISEMFs were procured from C57BL/6 mice. Crypts and single ISCs were grown in vitro into enteroids, in the presence or absence of ISEMFs. ISEMFs enhanced the growth of intestinal epithelium in vitro in a proximity-dependent fashion, with co-cultures giving rise to larger enteroids than monocultures. Co-culture of ISCs with supportive ISEMFs relinquished the requirement of exogenous R-spondin1 to sustain long-term growth and differentiation of ISCs. Mono- and co-cultures were implanted subcutaneously in syngeneic mice. Co-culture with ISEMFs proved necessary for successful in vivo engraftment and proliferation of enteroids; implants without ISEMFs did not survive. ISEMF whole transcriptome sequencing and qPCR demonstrated high expression of specific R-spondins, well-described Wnt agonists that supports ISC growth. Specific non-supportive ISEMF populations had reduced expression of R-spondins. The addition of ISEMFs in intestinal epithelial culture therefore recapitulates a critical element of the intestinal stem cell niche and allows for its experimental interrogation and biodesign-driven manipulation.