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1.
Toxicol Appl Pharmacol ; 484: 116887, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38458354

RESUMEN

AIMS: Gastrointestinal paresthesia and dysmotility are common side effects of vincristine (VCR) chemotherapy, which have become one of the factors for dose reduction, therapy delay or discontinuation. However, the mechanism is not entirely clear, whether it is related to autonomic nerves injury remains unknown. Therefore, we aimed to study whether VCR-induced gastrointestinal toxicity is related to changes in mesenteric afferent activity. METHODS: The effects of a single VCR stimulation and long-term systemic VCR treatment on mesenteric afferent activity were investigated by directly recording mesenteric afferent discharge in vitro. RESULTS: Our results showed that a single VCR (0.001-1 µmol/L) stimulation obviously increased the spontaneous, chemically evoked and mechanically evoked discharge of jejunal and colonic mesenteric afferents. This kind of hypersensitivity of VCR could be blocked by capsazepine, a transient receptor potential vanilloid 1 (TRPV1) antagonist. For the mice treated with VCR (0.1 mg/kg/d, i.p.) for 14 days, the abdominal withdrawal reflex and writhing response scores were reduced. Meanwhile, the spontaneous discharge of colonic mesenteric afferents and the afferent response to VCR was downregulated, and the afferent sensitivity to chemical and mechanical stimulation was reduced. Moreover, the expression of TRPV1 in colon was decreased. CONCLUSIONS: These results suggest that the direct stimulation by VCR increases the mesenteric afferent sensitivity by activating TRPV1, which may be the reason of VCR-induced abdominal pain; the long-term systemic treatment of VCR decreases mesenteric afferent sensitivity by reducing TRPV1, which may be the reason of VCR-induced constipation.


Asunto(s)
Canales Catiónicos TRPV , Ratones , Animales , Vincristina/toxicidad , Regulación hacia Abajo , Canales Catiónicos TRPV/metabolismo
2.
Biotechnol Bioeng ; 121(6): 1973-1985, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38548653

RESUMEN

Nanobody (Nb), the smallest antibody fragments known to bind antigens, is now widely applied to various studies, including protein structure analysis, bioassay, diagnosis, and biomedicine. The traditional approach to generating specific nanobodies involves animal immunization which is time-consuming and expensive. As the understanding of the antibody repertoire accumulation, the synthetic library, which is devoid of animals, has attracted attention widely in recent years. Here, we describe a synthetic phage display library (S-Library), designed based on the systematic analysis of the next-generation sequencing (NGS) of nanobody repertoire. The library consists of a single highly conserved scaffold (IGHV3S65*01-IGHJ4*01) and complementary determining regions of constrained diversity. The S-Library containing 2.19 × 108 independent clones was constructed by the one-step assembly and rapid electro-transformation. The S-Library was screened against various targets (Nb G8, fusion protein of Nb G8 and green fluorescent protein, bovine serum albumin, ovalbumin, and acetylcholinesterase). In comparison, a naïve library (N-Library) from the source of 13 healthy animals was constructed and screened against the same targets as the S-Library. Binders were isolated from both S-Library and N-Library. The dynamic affinity was evaluated by the biolayer interferometry. The data confirms that the feature of the Nb repertoire is conducive to reducing the complexity of library design, thus allowing the S-Library to be built on conventional reagents and primers.


Asunto(s)
Biblioteca de Péptidos , Anticuerpos de Dominio Único , Anticuerpos de Dominio Único/genética , Anticuerpos de Dominio Único/química , Anticuerpos de Dominio Único/inmunología , Animales , Técnicas de Visualización de Superficie Celular/métodos
3.
Inflammopharmacology ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38767761

RESUMEN

Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disease with a relapsing-remitting course. Although its etiology remains unknown, excessive oxidative stress in colon is a major intermediate factor that can promote the progression of UC. In the present study, we investigated the effect and the underlying mechanisms of 4-Octyl itaconate (OI) on dextran sulfate sodium (DSS)-induced UC in mice. Our work identified that OI alleviated the colitis by reducing the oxidative stress and the apoptosis in colon tissue, then increasing the tight junction proteins expression and in turn enhancing the intestinal barrier function, thereby creating less severe inflammatory responses. Moreover, our results demonstrated that OI reduced the Kelch-like ECH-associated protein 1 (KEAP1) expression and subsequent upregulated nuclear factor E2-related factor (NRF2) expression and its nuclear translocation which in turn induced the expression of glutathione S-transferase (GST) and NAD(P)H: quinone oxidoreductase 1 (NQO1). In addition, ML385, a NRF2 antagonist, can inhibit the protective effects of OI on UC, indicating that the role of OI in this colitis model could be dependent on the activation of KEAP1-NRF2 pathway. Notably, OI co-administration significantly enhanced the therapeutic effects of mesalazine or 1400W on UC. Collectively, itaconate may have a great potential for use in the treatment of IBD.

4.
Clin Sci (Lond) ; 137(1): 109-127, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36503938

RESUMEN

Menopausal women often face long-term estrogen treatment. G protein-coupled estrogen receptor (GPER) expressed in intestinal crypt was activated by estrogen therapy, but it was unclear whether chronic GPER activation during menopause had an effect on intestinal stem cells (ISCs). We tested the effect of chronic GPER activation on ISCs of ovariectomized (OVX) mice by injection of the selective GPER agonist G-1 for 28 days, or G-1 stimulation of organoids derived from crypts of OVX mice. G-1 up-regulated crypt depth, the number of Ki67+, bromodeoxyuridine+ cells and Olfm4+ ISCs, and the expression of ISCs marker genes (Lgr5, Olfm4 and Axin2). G-1 administration promoted organoid growth, increased the number of EdU+ cells per organoid and protein expression of Cyclin D1 and cyclin B1 in organoids. After G-1 treatment in vivo or in vitro, Paneth cell-derived Wnt3, Wnt3 effector ß-catenin and Wnt target genes c-Myc and Cyclin D1 increased in ileum or organoids. Once blocking the secretion of Wnt3 from Paneth cells, the effects of G-1 on organoids growth, ISCs marker genes and Wnt/ß-catenin signaling were abolished. G-1 did not affect the number of Paneth cells in ex vivo organoids, while activated Mmp7/cryptdin program in Paneth cells, promoted their maturation, and increased the expression of lysozyme protein. G-1 pretreatment in OVX mice inhibited radiation-induced ISCs proliferation injury and enhanced the resistance of mice to intestinal injury. In conclusion, chronic GPER activation prompted the Wnt3 synthesis in Paneth cells, thus increased the proliferation of ISCs via activation of Wnt3/ß-catenin signaling in OVX mice.


Asunto(s)
Ciclina D1 , Células de Paneth , Ratones , Femenino , Animales , Células de Paneth/metabolismo , Ciclina D1/metabolismo , beta Catenina/metabolismo , Íleon/metabolismo , Células Madre , Vía de Señalización Wnt , Proliferación Celular , Estrógenos/farmacología , Estrógenos/metabolismo , Mucosa Intestinal/metabolismo , Proteína Wnt3/metabolismo , Proteína Wnt3/farmacología
5.
BMC Med Educ ; 23(1): 661, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37705019

RESUMEN

BACKGROUND: Chinese universities are increasingly recruiting foreign students, and problem-based learning (PBL) is an effective approach to integrating those students. This study focuses on the role of intercultural sensitivity and group ethnic composition on the quality of group interaction in medical problem-based learning in China. METHODS: This paper reports an investigation of the differences in three types of group interaction (exploratory questions, cumulative reasoning, and handling conflict) among 139 s-year medical undergraduates from two backgrounds (Chinese and foreign) in a PBL setting. The roles of intercultural sensitivity, group ethnic composition, and students' personal characteristics including age, gender and ethnicity on students' perceptions of the three types of interaction were quantitatively analyzed. A 35-item questionnaire and demographic survey were administered to second year medical undergraduates. RESULTS: The results indicated that group ethnic composition was a significant negative predictor while intercultural sensitivity was a strong positive predictor of group interactions involving exploratory questions and cumulative reasoning. In addition, group heterogeneity in terms of age and ethnicity were significant predictors of group interaction. CONCLUSIONS: The findings of this study provide insights for strategically designing effective multiethnic group learning environments that encourage interaction and collaboration.


Asunto(s)
Dinámica de Grupo , Aprendizaje Basado en Problemas , Humanos , Pueblo Asiatico , China , Etnicidad , Universidades
6.
BMC Med Educ ; 22(1): 560, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35854299

RESUMEN

BACKGROUND: Students can take different approaches to using online learning technologies: deep and surface. It is important to understand the relationship between instructor role and student approaches to using online learning technologies in online learning settings supported by cloud computing techniques. METHODS: A descriptive, cross-sectional study was conducted to analyze the relationships between medical students' perceptions of instructor role (instructor support, instructor-student interaction, and instructor innovation) and students' approaches to using online learning technologies in cloud-based virtual classrooms. A 25-item online questionnaire along with a sheet with basic demographic was administered to all medical students at Qilu Medical Schools of Shandong University China. Overall, 213 of 4000 medical students (5.34%) at the medical school participated in the survey. RESULTS: The results showed high levels of medical students' perceived instructor support, instructor-student interaction and instructor innovation. Most students adopted the deep approaches to using online learning technologies. Instructor support, instructor-student interaction and innovation were positively related to students' deep approaches to using online learning technologies. Instructor support was negatively related to students' surface approaches to using online learning technologies. CONCLUSIONS: The relationship between instructor role (instructor support, instructor-student interaction and instructor innovation) and students' approaches to using online learning technologies highlight the importance of instructor support and innovation in facilitating students' adoption of desirable approaches to learning from the application of technologies.


Asunto(s)
Educación a Distancia , Estudiantes de Medicina , Nube Computacional , Estudios Transversales , Educación a Distancia/métodos , Humanos , Universidades
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(5): 482-491, 2022 May 15.
Artículo en Zh | MEDLINE | ID: mdl-35644187

RESUMEN

OBJECTIVES: To develop the birth weight curve of singleton neonates with a gestational age of 24-42 weeks, and to investigate the regional differences of the birth weight curve. METHODS: A total of 11 maternal and child health hospitals with more than 7 000 neonates delivered annually were selected in 11 cities of China (Haikou, Guangzhou, Shenzhen, Liuzhou, Guilin, Quanzhou, Chongqing, Chengdu, Changsha, Ningbo, and Lianyungang), and all live singleton neonates delivered in the 11 hospitals from January 1, 2017 to December 31, 2020 were enrolled for the development of birth weight curves. RESULTS: A total of 93 720 singleton neonates with a gestational age of 24-42 weeks from the 11 cities were included in the study. The reference values of the 3rd-97th percentiles of birth weight of singleton neonates for the total of the 11 cities and for each of the 11 cities were established, and the birth weight percentile curves were drawn. The birth weight curve level of singleton neonates in Shenzhen and Quanzhou was almost the same as the average level of the 11 cities; the birth weight curve level of singleton neonates in Haikou, Guangzhou, Guilin, and Liuzhou was slightly lower than the average level of the 11 cities; the birth weight curve level of singleton neonates in Chongqing, Chengdu, and Changsha was slightly higher than the average level of the 11 cities; the birth weight curve level of singleton neonates in Ningbo and Lianyungang was higher than the average level of the 11 cities. The average birth weight curve level of singleton neonates in the 11 cities were very close to that of China Neonatal Cooperation Network in 2011-2014. CONCLUSIONS: The reference values of the 3rd-97th percentiles of birth weight of singleton neonates for the total of the 11 cities and for each of the 11 cities are developed, which can be used as a reference for evaluating the intrauterine growth of singleton neonates in the region. The level of intrauterine growth of neonates in some cities is different from the national level.


Asunto(s)
Edad Gestacional , Peso al Nacer , Niño , China , Ciudades , Humanos , Lactante , Recién Nacido , Valores de Referencia
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(11): 1219-1225, 2022 Nov 15.
Artículo en Zh | MEDLINE | ID: mdl-36398547

RESUMEN

OBJECTIVES: To develop the birth weight curves of the Chinese Han (26-41 weeks of gestation) and Zhuang (28-41 weeks of gestation) singleton neonates in 11 cities of China, as well as the birth weight means of full-term neonates of 14 Chinese ethnic groups. METHODS: The live singleton neonates who were born in 11 maternal and child health care hospitals from 11 cities of China between January 2017 and December 2020 were classified according to the mother's ethnic group. Birth weight means were calculated for the full-term neonates of each ethnic group. For the Han and Zhuang singleton neonates with a large sample size, the Lambda-Mu-Sigma (LMS) method was used to establish the birth weight percentile curves of the Han and Zhuang singleton neonates with different gestational ages. RESULTS: A total of 105 365 live singleton neonates were included, among whom the Han neonates had the highest number of 84 851 (26-41 weeks of gestation), followed by the Zhuang neonates (12 803 neonates with a gestational age of 28-41 weeks). The neonates of the other Chinese ethnic groups enrolled were live full-term singleton neonates, with a sample size of more than 100 neonates for each ethnic group. The 3rd-97th percentile curves of birth weight were established for the Han singleton neonates with a gestational age of 26-41 weeks and the Zhuang singleton neonates with a gestational age of 28-41 weeks. The birth weight curves of the Han singleton neonates at each gestational age were higher than those of the Zhuang singleton neonates. Birth weight means (3 199-3 499 g) and standard deviations were determined for 14 Chinese ethnic groups, i.e., Li, Mulao, Zhuang, Yao, Dong, Miao, Han, Buyi, Mongolian, Tujia, Yi, Hui, Man, and Korean ethnic groups. The Li ethnic group had the lowest birth weight, followed by the Mulao, Zhuang, Yao, Dong, Miao, Han, Buyi, Mongolian, Tujia, Yi, Hui, Man, and Korean ethnic groups. CONCLUSIONS: The 3rd-97th percentile curves of birth weight are developed for the Han (26-41 weeks of gestation) and Zhuang (28-41 weeks of gestation) singleton neonates in 11 cities of China, and birth weight means are determined for the full-term neonates of 14 Chinese ethnic groups in 11 cities of China, which provides a reference for evaluating the intrauterine growth of neonates in these ethnic groups.


Asunto(s)
Etnicidad , Recién Nacido , Masculino , Niño , Humanos , Lactante , Peso al Nacer , Ciudades , Edad Gestacional , China
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(8): 899-907, 2022 Aug 15.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-36036129

RESUMEN

OBJECTIVES: To develop the birth weight curve of twin neonates with a gestational age of 25-40 weeks, and to investigate the regional differences of the birth weight curve. METHODS: A total of 11 maternal and child health care hospitals with more than 7 000 neonates delivered annually were selected in 11 cities of China (Haikou, Guangzhou, Liuzhou, Guilin, Quanzhou, Shenzhen, Chongqing, Chengdu, Changsha, Ningbo, and Lianyungang), and all live twin neonates delivered in the 11 hospitals from January 1, 2017 to December 31, 2020 were enrolled for the development of birth weight curves. RESULTS: A total of 17 256 twin neonates with a gestational age of 25-40 weeks from the 11 cities were included in the study. The reference values of the 3rd-97th percentiles of birth weight of twin neonates for the total of the 11 cities and for each of the 11 cities in China were established, and the birth weight percentile curves were drawn. The birth weight curve level of twin neonates in Liuzhou was lower than the average level of the 11 cities; the birth weight curve level of twin neonates in Ningbo was higher than the average level of the 11 cities; the birth weight curve level of twin neonates in Lianyungang was obviously higher than the average level of the 11 cities; the birth weight curve level of twin neonates in other 8 cities was almost the same as the average level of the 11 cities. CONCLUSIONS: The reference values of the 3rd-97th percentiles of birth weight of twin neonates for the total of the 11 cities and for each of the 11 cities are developed, which can be used as a reference for evaluating the intrauterine growth of twin neonates in the region. The level of intrauterine growth of twin neonates in some cities is different from the average level of the 11 cities of China.


Asunto(s)
Gemelos , Peso al Nacer , Niño , China , Ciudades , Edad Gestacional , Humanos , Lactante , Recién Nacido
10.
J Neuroinflammation ; 18(1): 261, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34749758

RESUMEN

BACKGROUND: The aim of the current study was to investigate the effect of macrophage polarization on the expression of oxytocin (OT) and the oxytocin receptor (OTR) in enteric neurons. METHODS: In this study, we used a classic colitis model and D-mannose model to observe the correlation between macrophage polarization and OT signalling system. In order to further demonstrate the effect of macrophages, we examined the expression of OT signalling system after depletion of macrophages. RESULTS: The data showed that, in vitro, following polarization of macrophages to the M1 type by LPS, the macrophage supernatant contained proinflammatory cytokines (IL-1ß, IL-6 and TNF-α) that inhibited the expression of OT and OTR in cultured enteric neurons; following macrophage polarization to the M2 type by IL4, the macrophage supernatant contained anti-inflammatory cytokines (TGF-ß) that promoted the expression of OT and OTR in cultured enteric neurons. Furthermore, M1 macrophages decreased the expression of the OT signalling system mainly through STAT3/NF-κB pathways in cultured enteric neurons; M2 macrophages increased the expression of the OT signalling system mainly through activation of Smad2/3 and inhibition of the expression of Peg3 in cultured enteric neurons. In a colitis model, we demonstrated that macrophages were polarized to the M1 type during the inflammatory phase, with significant decreased in the expression of OT and OTR. When macrophages were polarized to the M2 type during the recovery phase, OT and OTR expression increased significantly. In addition, we found that D-mannose increased the expression of OT and OTR through polarization of macrophages to the M2 type. CONCLUSIONS: This is the first study to demonstrate that macrophage polarization differentially regulates the expression of OT and OTR in enteric neurons.


Asunto(s)
Sistema Nervioso Entérico/metabolismo , Macrófagos/inmunología , Neuronas/metabolismo , Oxitocina/metabolismo , Receptores de Oxitocina/metabolismo , Animales , Diferenciación Celular/inmunología , Colitis/inmunología , Colitis/metabolismo , Sistema Nervioso Entérico/inmunología , Ratones , Ratones Endogámicos C57BL , Neuronas/inmunología , Oxitocina/inmunología , Receptores de Oxitocina/inmunología , Transducción de Señal/inmunología
11.
J Pharmacol Exp Ther ; 376(2): 281-293, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33318078

RESUMEN

G protein-coupled estrogen receptor (GPER) might be involved in ulcerative colitis (UC), but the direct effect of GPER on UC is still unclear. We used male C57BL/6 mice to establish the acute colitis model with administration of dextran sulfate sodium and explored the effect of GPER on acute colitis and its possible mechanism. The selective GPER agonist G-1 inhibited weight loss and colon shortening and decreased the disease activity index for colitis and histologic damage in mice with colitis. All of these effects were prevented by a selective GPER blocker. G-1 administration prevented the dysfunction of tight junction protein expression and goblet cells in colitis model and thus inhibited the increase of mucosal permeability in colitis-suffering mice significantly. GPER activation reduced expression of glucose-regulating peptide-78 and anti-CCAAT/enhancer-binding protein homologous protein and attenuated the three arms of the unfolded protein response in colitis. G-1 therapy inhibited the increase of cleavage caspase-3- and TUNEL-positive cells in colonic crypts in the colitis model, increased the number of Ki67- and bromodeoxyuridine-positive cells in crypts, and reversed the decrease of cyclin D1 and cyclin B1 expression in colitis, indicating its protective effect on crypt cells. In cultured CCD841 cells, G-1 treatment fought against cell injury induced by endoplasmic reticulum stress. These findings demonstrate that GPER activation prevents colitis by protecting the colonic crypt cells, which are associated with inhibition of endoplasmic reticulum stress. SIGNIFICANCE STATEMENT: We demonstrate that G protein-coupled estrogen receptor (GPER) activation prevents dextran sulfate sodium-induced acute colitis by protecting the crypt cells, showing that it inhibited the crypt cell apoptosis and protected proliferation of crypt cells, which resulted in protection of the intestinal mucosal barrier. This protective effect was achieved (at least in part) by inhibiting endoplasmic reticulum stress. Mucosal healing is regarded as a key therapeutic target for colitis, and GPER is expected to become a new therapeutic target for colitis.


Asunto(s)
Antiinflamatorios/farmacología , Colitis Ulcerosa/metabolismo , Enterocitos/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Células Madre/efectos de los fármacos , Animales , Antiinflamatorios/uso terapéutico , Apoptosis , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Células Cultivadas , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/prevención & control , Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico , Células Caliciformes/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Células Madre/metabolismo , Proteínas de Uniones Estrechas/genética , Proteínas de Uniones Estrechas/metabolismo , Respuesta de Proteína Desplegada
12.
Clin Sci (Lond) ; 135(4): 597-611, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-33564880

RESUMEN

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.


Asunto(s)
Colitis Ulcerosa/inmunología , Células Dendríticas/inmunología , Oxitocina/metabolismo , Oxitocina/farmacología , Receptores de Oxitocina/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Colitis/inducido químicamente , Células Dendríticas/metabolismo , Sulfato de Dextran/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Oxitocina/sangre , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Oxitocina/genética , Transducción de Señal
13.
Adv Exp Med Biol ; 1315: 67-98, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34302689

RESUMEN

The pathways and mechanisms of the production of H2S in the gastrointestinal tract are briefly described, including endogenous H2S produced by the organism and H2S from microorganisms in the gastrointestinal tract. In addition, the physiological regulatory functions of H2S on gastrointestinal motility, sensation, secretion and absorption, endocrine system, proliferation and differentiation of stem cells, and the possible mechanisms involved are introduced. In view of the complexity of biosynthesis, physiological roles, and the mechanism of H2S, this chapter focuses on the interactions and dynamic balance among H2S, gastrointestinal microorganisms, and the host. Finally, we focus on some clinical gastrointestinal diseases, such as inflammatory bowel disease, colorectal cancer, functional gastrointestinal disease, which might occur or develop when the above balance is broken. Pharmacological regulation of H2S or the intestinal microorganisms related to H2S might provide new therapeutic approaches for some gastrointestinal diseases.


Asunto(s)
Enfermedades Gastrointestinales , Sulfuro de Hidrógeno , Microbiota , Motilidad Gastrointestinal , Tracto Gastrointestinal , Humanos
14.
J Cell Physiol ; 234(12): 23256-23267, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31161632

RESUMEN

Current therapies including pharmaceutical intervention and surgery have limited efficacy on stress urinary incontinence (SUI). One type of SUI is due to low intraurethral pressure caused by the disabled contraction of urethral smooth muscle (USM). However, the molecular mechanisms underlying the motility of USM remain unknown. Here, we show that USM represents spontaneous tone after stretching in humans and mice. Deletion of TMEM16A in the smooth muscle of mice abolishes spontaneous urethral tone. Furthermore, ClCa currents and [Ca2+ ]i in TMEM16ASMKO mice were largely impaired. Inhibitors of ryanodine receptor (RyR), TMEM16A encoded calcium-activated chloride channel (ClCa ) and L-type voltage-dependent calcium channel (VDCC) fully prevented spontaneous tone accompanied by a significant decrease of intracellular calcium concentration ([Ca2+ ]i ). In summary, RyR-ClCa -VDCC signaling contributes to spontaneous USM tone. This finding may provide a new promising approach for women with stress SUI who reject surgery.


Asunto(s)
Anoctamina-1/metabolismo , Canales de Calcio/metabolismo , Tono Muscular/fisiología , Músculo Liso/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Uretra/metabolismo , Animales , Canales de Cloruro/metabolismo , Femenino , Humanos , Ratones , Ratones Noqueados , Miocitos del Músculo Liso/metabolismo , Transducción de Señal , Incontinencia Urinaria de Esfuerzo/metabolismo
15.
Clin Sci (Lond) ; 133(18): 1977-1992, 2019 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-31519790

RESUMEN

Inflammatory bowel disease (IBD) is a chronic intestinal inflammation, but the accurate etiology remains to be elucidated. Increasing evidence has shown that macrophages polarize to different phenotypes depending on the intestinal microenvironment and are associated with the progression of IBD. In the present study, we investigated the effect of oxytocin, a neuroendocrinal, and pro-health peptide, on the modulation of macrophages polarization and the progression of experimental colitis. Our data demonstrated that oxytocin decreased the sensitivity of macrophages to lipopolysaccharide stimulation with lower expression of inflammatory cytokines, like IL-1ß, IL-6, and TNF-α, but increased the sensitivity to IL-4 stimulation with enhanced expression of M2-type genes, arginase I (Arg1), CD206, and chitinase-like 3 (Chil3). This bidirectional modulation was partly due to the up-regulation of ß-arrestin2 and resulted in the inhibition of NF-κB signaling and reinforcement of Signal transducer and activator of transcription (STAT) 6 phosphorylation. Moreover, oxytocin receptor (OXTR) myeloid deficiency mice were more susceptible to dextran sulfate sodium (DSS) intervention compared with the wild mice. For the first time, we reveal that oxytocin-oxytocin receptor system participates in modulating the polarization of macrophages to an anti-inflammatory phenotype and alleviates experimental colitis. These findings provide new potential insights into the pathogenesis and therapy of IBD.


Asunto(s)
Colitis/patología , Inflamación/patología , Intestinos/patología , Macrófagos/patología , Oxitocina/farmacología , Adulto , Anciano , Animales , Polaridad Celular/efectos de los fármacos , Sulfato de Dextran , Femenino , Humanos , Mediadores de Inflamación/metabolismo , Interleucina-4/metabolismo , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Modelos Biológicos , FN-kappa B/metabolismo , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Receptores de Oxitocina/metabolismo , Factor de Transcripción STAT6/metabolismo , Células THP-1 , beta-Arrestinas/metabolismo
16.
Clin Sci (Lond) ; 133(3): 449-464, 2019 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-30705108

RESUMEN

The intestinal ischemia/reperfusion (I/R) injury is a common clinical event related with high mortality in patients undergoing surgery or trauma. Estrogen exerts salutary effect on intestinal I/R injury, but the receptor type is not totally understood. We aimed to identify whether the G protein-coupled estrogen receptor (GPER) could protect the intestine against I/R injury and explored the mechanism. Adult male C57BL/6 mice were subjected to intestinal I/R injury by clamping (45 min) of the superior mesenteric artery followed by 4 h of intestinal reperfusion. Our results revealed that the selective GPER blocker abolished the protective effect of estrogen on intestinal I/R injury. Selective GPER agonist G-1 significantly alleviated I/R-induced intestinal mucosal damage, neutrophil infiltration, up-regulation of TNF-α and cyclooxygenase-2 (Cox-2) expression, and restored impaired intestinal barrier function. G-1 could ameliorate the impaired crypt cell proliferation ability induced by I/R and restore the decrease in villus height and crypt depth. The up-regulation of inducible nitric oxide synthase (iNOS) expression after I/R treatment was attenuated by G-1 administration. Moreover, selective iNOS inhibitor had a similar effect with G-1 on promoting the proliferation of crypt cells in the intestinal I/R model. Both GPER and iNOS were expressed in leucine-rich repeat containing G-protein coupled receptor 5 (Lgr5) positive stem cells in crypt. Together, these findings demonstrate that GPER activation can prompt epithelial cell repair following intestinal injury, which occurred at least in part by inhibiting the iNOS expression in intestinal stem cells (ISCs). GPER may be a novel therapeutic target for intestinal I/R injury.


Asunto(s)
Mucosa Intestinal/metabolismo , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Daño por Reperfusión/metabolismo , Animales , Proliferación Celular , Humanos , Intestinos/cirugía , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Receptores de Estrógenos/genética , Receptores Acoplados a Proteínas G/genética , Daño por Reperfusión/genética , Daño por Reperfusión/fisiopatología
17.
Soft Matter ; 15(44): 9066-9075, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31650138

RESUMEN

Effective removal of oil spills or organic pollutant oils from water is of global significance for environmental protection. However, traditional techniques usually suffer from the limits of low efficiency and high cost. In this study, sponge-like polyamide 6/organic montmorillonite (PA 6/OMMT) composite absorbents were fabricated through a large-scale solution foaming method. Aqueous sodium carbonate solution was injected into a PA/formic acid solution with well-dispersed nanoclay to generate CO2 and meanwhile initiate the phase separation of PA molecules from the solvent. Both mesopores and macropores existed in the prepared sponges. The effect of OMMT content on the microstructures and adsorption properties was investigated. Upon increasing the OMMT fraction in composite sponges, the pore size decreased and the fraction of mesopore increased. Better adsorption properties were thus obtained. When OMMT nanoplatelets accounted for 10%, the corresponding sponge had an uptake capacity of 12.5-22.1 g g-1 for diverse oils or organic solvents. Moreover, the composite sponges absorbed oils and organic solvents rapidly and reached saturation in 20 s. When it was coated with methyltrichlorosilane (MTS), the static water contact angle on the surface of the sponge increased from 88° to 115°. The selective absorption of oil from an oil/water mixture was improved. A greatly promising approach is provided to make commercial polyamide into highly porous functional materials for the cleanup of large-scale oil spills.

18.
BMC Med Educ ; 19(1): 315, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31438946

RESUMEN

BACKGROUND: The authors' medical school has adopted an inverted classroom model (ICM) for physiology classes. This study aimed to determine students' learning styles and investigate the relationship between learning style and satisfaction with different instruction approaches and components of the ICM. METHODS: One hundred and twenty-one second-year dental students participated in this study, which had a 77.6% participation rate. The Kolb Learning Style Inventory, a sociodemographic questionnaire, and a satisfaction survey were administered after course completion. RESULTS: In both the traditional and ICM classes, most of the participants were convergers (56.9 and 54%) and assimilators (20.7 and 25.4%), and the rest of the participants were accommodators (15.5 and 12.7%) and divergers (6.9 and 8%). Learning style did not influence participants' satisfaction and did not predict their satisfaction with the traditional and ICM approaches. The satisfaction scores for the four components of the ICM were not significantly different by learning style. The mean satisfaction scores of the ICM approach were higher than those of the traditional approach in all learning style groups. All of the participants in the ICM class were more satisfied with the online and teacher-student interaction components than the student group discussion and presentation components. CONCLUSIONS: Learning style may not be a potential contributing factor for optimizing the implementation of the ICM. Instead of focusing on learning styles, further research must investigate how to design more efficient online courses, determine appropriate levels of learning materials, provide more online instructional interaction, and help students overcome their feelings of fear.


Asunto(s)
Educación en Odontología/métodos , Aprendizaje , Estudiantes de Odontología , Enseñanza/normas , Educación en Odontología/normas , Evaluación Educacional , Humanos , Satisfacción Personal , Aprendizaje Basado en Problemas , Encuestas y Cuestionarios
19.
J Appl Toxicol ; 38(3): 341-350, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29044621

RESUMEN

Alcoholic liver disease (ALD) is a consequence of heavy and prolonged alcohol consumptions. We previously demonstrated a hepatic gamma-aminobutyric acid (GABA) signaling system that protects the liver from toxic injury. The present study was designed to investigate the role of the hepatic GABA signaling system in the process of acute ethanol exposure-induced liver injury. Our results showed that the expression of GABA synthesizing enzyme glutamic acid decarboxylase and type A GABA receptor (GABAA R) subunits was upregulated in ethanol-treated mice compared with saline-treated controls. Remarkably, pretreatment of mice with GABA (1.5 mg kg-1 body weight, intraperitoneal injection [i.p.]) or with the GABAA R agonist muscimol (1.2 mg kg-1 body weight, i.p.) protected the liver against ethanol toxicity and improved liver function, whereas pretreatment of mice with the GABAA R antagonist bicuculline (2.0 mg kg-1 body weight, i.p.) worsened the liver function. Further analyses suggest that GABAA R-mediated signaling protects the liver from ethanol injury by, at least partially, inhibiting the IRE1α-ASK1-JNK pro-apoptotic pathway in hepatocytes in the process of ethanol-induced endoplasmic reticulum stress response.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Etanol , Hepatopatías Alcohólicas/metabolismo , Hígado/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Enfermedad Aguda , Adulto , Animales , Apoptosis/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Modelos Animales de Enfermedad , Estrés del Retículo Endoplásmico/efectos de los fármacos , Endorribonucleasas/metabolismo , Agonistas de Receptores de GABA-A/farmacología , Antagonistas de Receptores de GABA-A/toxicidad , Glutamato Descarboxilasa/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Hígado/efectos de los fármacos , Hígado/patología , Hepatopatías Alcohólicas/etiología , Hepatopatías Alcohólicas/patología , Hepatopatías Alcohólicas/prevención & control , MAP Quinasa Quinasa Quinasa 5/metabolismo , Masculino , Ratones Endogámicos C57BL , Persona de Mediana Edad , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores de GABA-A/metabolismo , Transducción de Señal , Regulación hacia Arriba , Adulto Joven
20.
Adv Physiol Educ ; 42(4): 711-717, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30431319

RESUMEN

The rapid development of mobile phones and communication networks is profoundly changing the lives of people in China. With the gradual growth of Wi-Fi on college and university campuses, Chinese schools are setting off a wave of teaching reform combining online material with traditional classroom instruction. We adapted a Chinese University massive open online course physiology course into a private university online course, specifically designed for second-semester bachelor's level nursing students at Taishan Medical University. This online course blended with classroom teaching was offered to 108 freshmen from two parallel reform classes. A third class of 55 students was offered the traditional classroom lecture-based course as a control. Impressive teaching effects were achieved in reform classes, as indicated by significant improvement in student performance on the final examination and positive student feedback. The student surveys showed that 68% of students preferred the blended course over traditional classroom courses. The most highly rated advantages of the blended course were flexible learning time (84%) and improvement of independent study skills (75%). As higher education enters the internet era, exploiting the high-quality cyber resources may be the fastest and most economical way to improve teaching efficiency and enhance students' study experience.


Asunto(s)
Instrucción por Computador/métodos , Evaluación Educacional/métodos , Aprendizaje , Fisiología/educación , Estudiantes de Enfermería , Instrucción por Computador/tendencias , Humanos , Aprendizaje/fisiología , Estudiantes de Enfermería/psicología
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