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1.
Gastroenterology ; 165(2): 391-401.e2, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37142201

RESUMO

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.


Assuntos
Adenocarcinoma , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Estados Unidos/epidemiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/prevenção & controle , Neoplasias Gástricas/tratamento farmacológico , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Estudos Retrospectivos , Incidência , Adenocarcinoma/epidemiologia , Adenocarcinoma/prevenção & controle , Adenocarcinoma/tratamento farmacológico , Antibacterianos/uso terapêutico
2.
BMC Womens Health ; 24(1): 41, 2024 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218826

RESUMO

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.


Assuntos
Cicloexilaminas , Neoplasias do Endométrio , Anemia de Fanconi , Ferroptose , Fenilenodiaminas , Feminino , Humanos , Espécies Reativas de Oxigênio/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/genética
3.
J Obstet Gynaecol Res ; 49(10): 2468-2474, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37488971

RESUMO

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.


Assuntos
Histerectomia , Laparoscopia , Retenção Urinária , Neoplasias do Colo do Útero , Feminino , Humanos , Histerectomia/efeitos adversos , Laparoscopia/efeitos adversos , Excisão de Linfonodo/efeitos adversos , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
4.
BMC Public Health ; 22(1): 1417, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35883126

RESUMO

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.


Assuntos
Publicidade , Televisão , Pequim , Bebidas , Criança , China , Alimentos , Indústria Alimentícia , Humanos , Lanches
5.
Gut ; 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380653

RESUMO

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.

6.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1676-1683, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32489049

RESUMO

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.


Assuntos
Células-Tronco Neoplásicas , Animais , Apigenina , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Glucuronatos , Proteínas Hedgehog , Humanos , Camundongos , Camundongos Nus
7.
Med Sci Monit ; 23: 4382-4390, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28892468

RESUMO

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.


Assuntos
Doença da Artéria Coronariana/genética , Estresse Oxidativo/genética , Telômero/fisiologia , Adulto , Idoso , Povo Asiático/genética , Aterosclerose/genética , Aterosclerose/fisiopatologia , Biomarcadores/sangue , China , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Leucócitos/fisiologia , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/sangue , Espécies Reativas de Oxigênio/metabolismo , Telômero/genética , Homeostase do Telômero/genética , Homeostase do Telômero/fisiologia
8.
Cell Tissue Res ; 365(1): 123-34, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26928041

RESUMO

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.


Assuntos
Envelhecimento/fisiologia , Intestinos/citologia , Técnicas de Cultura de Tecidos/métodos , Animais , Criopreservação , Meios de Cultivo Condicionados/farmacologia , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Camundongos , Miofibroblastos/citologia , Miofibroblastos/efeitos dos fármacos , Sus scrofa , Temperatura , Transdução Genética
9.
Org Biomol Chem ; 13(47): 11472-85, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26451708

RESUMO

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.


Assuntos
Acetonitrilas/química , Alcaloides/síntese química , Indazóis/síntese química , Termodinâmica , Alcaloides/química , Elétrons , Radicais Livres/síntese química , Radicais Livres/química , Indazóis/química , NAD/química , Oxirredução , Prótons
10.
Gastroenterology ; 145(2): 383-95.e1-21, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23644405

RESUMO

BACKGROUND & AIMS: Identification of intestinal stem cells (ISCs) has relied heavily on the use of transgenic reporters in mice, but this approach is limited by mosaic expression patterns and difficult to directly apply to human tissues. We sought to identify reliable surface markers of ISCs and establish a robust functional assay to characterize ISCs from mouse and human tissues. METHODS: We used immunohistochemistry, real-time reverse-transcription polymerase chain reaction, and fluorescence-activated cell sorting (FACS) to analyze intestinal epithelial cells isolated from mouse and human intestinal tissues. We compared different combinations of surface markers among ISCs isolated based on expression of Lgr5-green fluorescent protein. We developed a culture protocol to facilitate the identification of functional ISCs from mice and then tested the assay with human intestinal crypts and putative ISCs. RESULTS: CD44(+)CD24(lo)CD166(+) cells, isolated by FACS from mouse small intestine and colon, expressed high levels of stem cell-associated genes. Transit-amplifying cells and progenitor cells were then excluded based on expression of GRP78 or c-Kit. CD44(+)CD24(lo)CD166(+) GRP78(lo/-) putative stem cells from mouse small intestine included Lgr5-GFP(hi) and Lgr5-GFP(med/lo) cells. Incubation of these cells with the GSK inhibitor CHIR99021 and the E-cadherin stabilizer Thiazovivin resulted in colony formation by 25% to 30% of single-sorted ISCs. CONCLUSIONS: We developed a culture protocol to identify putative ISCs from mouse and human tissues based on cell surface markers. CD44(+)CD24(lo)CD166(+), GRP78(lo/-), and c-Kit(-) facilitated identification of putative stem cells from the mouse small intestine and colon, respectively. CD44(+)CD24(-/lo)CD166(+) also identified putative human ISCs. These findings will facilitate functional studies of mouse and human ISCs.


Assuntos
Células-Tronco Adultas/metabolismo , Antígenos de Superfície/metabolismo , Mucosa Intestinal/citologia , Molécula de Adesão de Leucócito Ativado/metabolismo , Animais , Antígeno CD24/metabolismo , Técnicas de Cultura de Células , Colo/citologia , Ensaio de Unidades Formadoras de Colônias , Chaperona BiP do Retículo Endoplasmático , Citometria de Fluxo , Proteínas de Choque Térmico/genética , Humanos , Receptores de Hialuronatos/metabolismo , Intestino Delgado/citologia , Camundongos , Proteínas Proto-Oncogênicas c-kit/metabolismo
11.
J Surg Res ; 183(1): 18-26, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23769018

RESUMO

BACKGROUND: One of the greatest challenges in scaffold-based tissue engineering remains poor and inefficient penetration of cells into scaffolds to generate thick vascularized and cellular tissues. Electrospinning has emerged as a preferred method for producing scaffolds with high surface area-to-volume ratios and resemblance to extracellular matrix. However, cellular infiltration and vascular ingrowth are insufficient because of lack of macropore interconnectivity in electrospun scaffolds with high-fiber density. In this study, we report a novel two-step electrospinning and laser cutting fabrication method to enhance the macroporosity of electrospun scaffolds. MATERIALS AND METHODS: Polycaprolactone dissolved in hexafluoroisopropanol was electrospun at 25 kV to create uniform 100-120 µm sheets of polycaprolactone fiber mats (1- to 5-µm fiber diameter) with an array of pores created using VERSA LASER CUTTER 2.3. Three groups of fiber mats with three distinct pore diameters (300, 160, and 80 µm, all with 15% pore area) were fabricated and compared with a control group without laser cut pores. After laser cutting, all mats were collagen coated and manually wrapped around a catheter six times to form six concentric layers before implantation into the omentum of Lewis rats. Cellular infiltration and vascular ingrowth were examined after 2 wk. RESULTS: Histologic analysis of 14-d samples showed that scaffolds with laser cut pores had close to 40% more cellular infiltration and increased vascular ingrowth in the innermost layers of the construct compared with the control group. Despite keeping pore area percentage constant between the three groups, the sheets with the largest pore size performed better than those with the smallest pore sizes. CONCLUSIONS: Porosity is the primary factor limiting the extensive use of electrospun scaffolds in tissue engineering. Our method of LASER cutting pores in electrospun fibrous scaffolds ensures uniform pore sizes, easily controllable and customizable pores, and enhances cellular infiltration and vascular ingrowth, demonstrating significant advancement toward utility of electrospun scaffolds in tissue engineering.


Assuntos
Lasers de Gás , Neovascularização Fisiológica , Alicerces Teciduais , Animais , Fenômenos Biomecânicos , Matriz Extracelular/fisiologia , Porosidade , Ratos , Ratos Endogâmicos Lew , Engenharia Tecidual/métodos
12.
Org Biomol Chem ; 11(36): 6071-89, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23917398

RESUMO

A classical but new kinetic equation to estimate activation energies of various hydride transfer reactions was developed according to transition state theory using the Morse-type free energy curves of hydride donors to release a hydride anion and hydride acceptors to capture a hydride anion and by which the activation energies of 187 typical hydride self-exchange reactions and more than thirty thousand hydride cross transfer reactions in acetonitrile were safely estimated in this work. Since the development of the kinetic equation is only on the basis of the related chemical bond changes of the hydride transfer reactants, the kinetic equation should be also suitable for proton transfer reactions, hydrogen atom transfer reactions and all the other chemical reactions involved with breaking and formation of chemical bonds. One of the most important contributions of this work is to have achieved the perfect unity of the kinetic equation and thermodynamic equation for hydride transfer reactions.


Assuntos
Hidrogênio/química , Prótons , Cinética , Estrutura Molecular , Compostos Orgânicos/química , Termodinâmica
13.
Cell Transplant ; 29: 963689720903709, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32907378

RESUMO

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.


Assuntos
Técnicas de Cultura de Células/métodos , Intestinos/fisiopatologia , Cadáver , Diferenciação Celular , Humanos
14.
Sci Rep ; 8(1): 13544, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30202095

RESUMO

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.


Assuntos
Intestinos/citologia , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Miócitos de Músculo Liso/fisiologia , Engenharia Tecidual/métodos , Animais , Animais Recém-Nascidos , Linhagem Celular , Colonoscopia , Feminino , Fibroblastos , Motilidade Gastrointestinal/fisiologia , Humanos , Enteropatias/fisiopatologia , Enteropatias/terapia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso/citologia , Miócitos de Músculo Liso/transplante , Poliésteres/química , Cultura Primária de Células , Alicerces Teciduais/química
15.
PLoS One ; 11(1): e0148216, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26820624

RESUMO

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.


Assuntos
Mucosa Intestinal/citologia , Intestino Delgado/citologia , Nódulos Linfáticos Agregados/citologia , Células-Tronco/citologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Células Cultivadas , Humanos , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Intestino Delgado/imunologia , Intestino Delgado/microbiologia , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/microbiologia , Ligante RANK/imunologia , Salmonella typhimurium/imunologia , Células-Tronco/imunologia
16.
Biomaterials ; 61: 75-84, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26001072

RESUMO

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.


Assuntos
Intestinos/crescimento & desenvolvimento , Músculo Liso/citologia , Músculo Liso/crescimento & desenvolvimento , Miócitos de Músculo Liso/fisiologia , Nanofibras/ultraestrutura , Alicerces Teciduais , Animais , Anisotropia , Proliferação de Células/fisiologia , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Intestinos/citologia , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/citologia , Nanofibras/química , Engenharia Tecidual/instrumentação
17.
PLoS One ; 10(5): e0127258, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26016485

RESUMO

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.


Assuntos
Colonoscopia , Imunocompetência , Injeções , Miofibroblastos/citologia , Animais , Sobrevivência Celular , Colo/citologia , Feminino , Mucosa Intestinal/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo
18.
Chinese Journal of School Health ; (12): 654-658, 2024.
Artigo em Chinês | WPRIM | ID: wpr-1031792

RESUMO

Objective@#To investigate the exposure to television advertising of sugar sweetened beverages and the use of persuasive marketing techniques among children and adolescents in Beijing, so as to provide evidence for reduing childrens intake of sugar sweetened beverages.@*Methods@#From October 19, 2020 to November 16, 2021, 32 days were randomly selected. The top four popular channels of children and adolescents aged 3-18 years were defined. Each channel was monitored from 6:00:00 to 23:59:59 for each date. A total of 2 304 h was recorded. Advertisements involving sugar sweetened beverages broadcast before, during or after the program were included. The frequency and the use of persuasive marketing techniques were analyzed.@*Results@#A total of 1 237 advertisements for sugar sweetened beverages were included, of which 50.93% were dairy beverages, 28.38% were teabased beverages, and 19.48% were vegetable protein beverages. The average frequency of sugar sweetened beverages advertisements on every channel was (0.62±1.29)piece/h. The frequency of sugar sweetened beverages advertisements on every local channel [(1.04±1.35)piece/h] and childrens channel [(1.11±1.61)piece/h] was separately higher than every national channel [(0.48±1.24)piece/h] and general channel [(0.12±0.48)piece/h] (t=-14.05, 31.64, P<0.01). There were seasonal differences in television advertising of sugar sweetened beverages, and were more frequent during lunch and dinner times. The most frequently used persuasive marketing techniques were "images of children" (74.54%), "nutritional message" (61.76%), "product composition details" (58.61%), "nutrition claim" (57.24%), and "nutrition function claim or other function claim" (53.11%).@*Conclusions@#Children and adolescents are often exposed to television advertisement of sugar sweetened beverages on childrens channels and during meal times. There is an urgent need to formulate relevant policies to regulate the marketing of sugar sweetened beverages advertisement and reduce children and adolescents intake.

19.
PLoS One ; 9(9): e107814, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25222024

RESUMO

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.


Assuntos
Colágeno Tipo I/metabolismo , Técnicas In Vitro , Mucosa Intestinal/citologia , Intestino Delgado/citologia , Membrana Basal/citologia , Membrana Basal/metabolismo , Técnicas de Cocultura , Colágeno/química , Colágeno Tipo I/química , Combinação de Medicamentos , Matriz Extracelular/química , Humanos , Mucosa Intestinal/crescimento & desenvolvimento , Mucosa Intestinal/metabolismo , Intestino Delgado/crescimento & desenvolvimento , Intestino Delgado/metabolismo , Laminina/química , Miofibroblastos/citologia , Proteoglicanas/química
20.
PLoS One ; 9(1): e84651, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24400106

RESUMO

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.


Assuntos
Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Miofibroblastos/metabolismo , Células-Tronco/metabolismo , Animais , Técnicas de Cultura de Células , Proliferação de Células , Células Cultivadas , Análise por Conglomerados , Perfilação da Expressão Gênica , Camundongos , Camundongos Transgênicos , Células-Tronco/citologia , Transcriptoma
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