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1.
Int J Biol Macromol ; 274(Pt 2): 133304, 2024 Jun 24.
Article de Anglais | MEDLINE | ID: mdl-38925189

RÉSUMÉ

Epithelial barrier impairment of intestinal inflammation leads to the leakage of bacteria, antigens and consequent persistent immune imbalance. Restoring the barrier function holds promise for management of intestinal inflammation, while the theragnostic strategies are limited. In this study, we developed a novel coating by catalase (CAT)-catalyzed polymerization of tannic acid (TA) and combined chelation network with Fe3+. TA-Fe3+ coating was self-polymerized in situ along the small intestinal mucosa, demonstrating persistent adhesion properties and protective function. In enteritis models, sequential administration of TA-Fe3+ complex solution effectively restored the barrier function and alleviated the intestinal inflammation. Overexpressed CAT in inflammatory lesion is more favorable for the in situ targeting growth of TA-Fe3+ coating onto the defective barrier. Based on the high longitudinal relaxivity of Fe3+, the pathologically catalyzed coating facilitated the visualization of intestinal barrier impairment through MRI. In conclusion, the novel TA-Fe3+ delivery coating proposed an alternative approach to promote theranostic intervention for intestinal diseases.

3.
Rev Esp Enferm Dig ; 2023 Nov 06.
Article de Anglais | MEDLINE | ID: mdl-37929977

RÉSUMÉ

BACKGROUND: Endoscopic resection (ER) of gastric submucosal tumors (G-SMTs) is challenging due to the difficulty of exposure. Traction-assisted ER has been shown to provide better outcomes than traditional endoscopic operation by exposing the dissection plane. In this study, we investigated the efficacy and safety of the snare traction-assisted method in ER of G-SMTs. METHOD: From May 2021 to March 2023, we used snare traction-assisted method to treat 24 patients with 24 G-SMTs in our department. Clinical characteristics and the outcomes of ER were recorded. RESULT: The mean tumor diameter was 1.8±0.9 cm. Six G-SMTs underwent endoscopic submucosal dissection (ESD), and 18 underwent endoscopic full-thickness resection (EFTR). En bloc resection and R0 resection was achieved in all the 24 lesions. The average procedure time was 45.4 ± 23.4 minutes. The patients were discharged in 5.0 days after procedures, without delayed bleeding or other adverse events. CONCLUSION: Snare traction-assisted method provides an effective traction for endoscopic resection of G-SMTs even if the tumor is difficult to remove. While further studies comparing the snare traction-assisted method with the conventional procedure are necessary.

4.
J Pharm Anal ; 13(1): 39-54, 2023 Jan.
Article de Anglais | MEDLINE | ID: mdl-36820075

RÉSUMÉ

Polyphyllin I (PPI) and polyphyllin II (PII) are the main active substances in the Paris polyphylla. However, liver toxicity of these compounds has impeded their clinical application and the potential hepatotoxicity mechanisms remain to be elucidated. In this work, we found that PPI and PII exposure could induce significant hepatotoxicity in human liver cell line L-02 and zebrafish in a dose-dependent manner. The results of the proteomic analysis in L-02 cells and transcriptome in zebrafish indicated that the hepatotoxicity of PPI and PII was associated with the cholesterol biosynthetic pathway disorders, which were alleviated by the cholesterol biosynthesis inhibitor lovastatin. Additionally, 3-hydroxy-3-methy-lglutaryl CoA reductase (HMGCR) and squalene epoxidase (SQLE), the two rate-limiting enzymes in the cholesterol synthesis, selected as the potential targets, were confirmed by the molecular docking, the overexpression, and knockdown of HMGCR or SQLE with siRNA. Finally, the pull-down and surface plasmon resonance technology revealed that PPI could directly bind with SQLE but not with HMGCR. Collectively, these data demonstrated that PPI-induced hepatotoxicity resulted from the direct binding with SQLE protein and impaired the sterol-regulatory element binding protein 2/HMGCR/SQLE/lanosterol synthase pathways, thus disturbing the cholesterol biosynthesis pathway. The findings of this research can contribute to a better understanding of the key role of SQLE as a potential target in drug-induced hepatotoxicity and provide a therapeutic strategy for the prevention of drug toxic effects with similar structures in the future.

5.
Stem Cell Res Ther ; 13(1): 422, 2022 08 19.
Article de Anglais | MEDLINE | ID: mdl-35986406

RÉSUMÉ

BACKGROUND: Mesenchymal stem cells (MSCs) exert anti-diabetic effects and improve long-term complications via secretory effects that regulate macrophage polarisation and attenuate inflammation. Enhancing the efficacy of MSCs needs to be explored further. The in vitro culture microenvironment influences the secretory profile of MSCs. Therefore, we hypothesised that a diabetic microenvironment would promote the secretion of cytokines responsible for macrophage polarisation, further attenuating systemic inflammation and enhancing the effects of MSCs on type 2 diabetes (T2D) and long-term diabetic complications. METHODS: Preconditioned adipose-derived mesenchymal stem cells (pre-ADSCs) were obtained after co-cultivating ADSCs in a diabetic metabolic environment (including high sugar, advanced glycation end-product, and lipopolysaccharides). The regulatory effects of pre-ADSCs on macrophages were observed in vitro. A T2D rat model was induced with a high-fat diet for 32 weeks combined with an intraperitoneal injection of streptozotocin. Sprague-Dawley (SD) rats were divided into four groups: normal group, diabetes without treatment group (PBS), ADSC treatment group, and pre-ADSC treatment group. ADSCs and pre-ADSCs were intravenously administered weekly to SD rats for 6 months, and then glucose homeostasis and long-term diabetic complications were evaluated in each group. RESULTS: The secretion of cytokines related to M2 macrophage polarisation (IL-6, MCP-1, etc.) was increased in the pre-ADSC group in the in vitro model. Pre-ADSC treatment significantly maintained blood glucose homeostasis, reduced insulin resistance, promoted islet regeneration, and ameliorated the complications related to diabetes in rats (chronic kidney disease, non-alcoholic steatohepatitis, lung fibrosis, and cataract) compared to the ADSC group (P < 0.05). Additionally, the number of anti-inflammatory M2 macrophage phenotypes was enhanced in tissues following pre-ADSC injections. Moreover, the expression of pro-inflammatory genes (iNOS, TNF-α, IL-1ß) was reduced whereas that of anti-inflammatory genes (Arg1, CD206, and Il-10) was increased after cultivation with pre-ADSCs. CONCLUSION: Diabetic microenvironment-preconditioned ADSCs effectively strengthen the capacity against inflammation and modulate the progress of long-term T2D complications.


Sujet(s)
Complications du diabète , Diabète expérimental , Diabète de type 2 , Cellules souches mésenchymateuses , Tissu adipeux , Animaux , Anti-inflammatoires/métabolisme , Cytokines/métabolisme , Diabète expérimental/complications , Diabète de type 2/métabolisme , Diabète de type 2/thérapie , Inflammation/métabolisme , Inflammation/thérapie , Cellules souches mésenchymateuses/métabolisme , Rats , Rat Sprague-Dawley
6.
Stem Cell Res Ther ; 13(1): 109, 2022 03 21.
Article de Anglais | MEDLINE | ID: mdl-35313972

RÉSUMÉ

BACKGROUND: Previous research has demonstrated that the spleen plays an important role in mesenchymal stem cell (MSC)-mediated alleviation of acute inflammation, as MSC infusion increases the spleen-derived anti-inflammatory cytokine interleukin 10 (IL-10) levels. However, studies on splenic involvement in MSC-induced protection against chronic inflammatory diseases are limited. Obesity is characterized by chronic low-grade inflammation, a key driver of insulin resistance. This study aims to evaluate the effects of MSCs on obesity-related insulin resistance and explore the underlying mechanism, particularly regarding splenic involvement. METHODS: We induced obesity in mice by feeding them high-fat diets for 20 weeks. Human umbilical cord-derived MSCs (UC-MSCs) were systemically infused into the obese mice once per week for 6 weeks. Systemic glucose metabolic homeostasis and insulin sensitivity in epididymal adipose tissue (EAT) were evaluated. Then, we conducted in vivo blockade of IL-10 during UC-MSC infusion by intraperitoneally administrating an IL-10-neutralizing antibody twice per week. We also investigated the therapeutic effects of UC-MSCs on obese mice after removal of the spleen by splenectomy. RESULTS: UC-MSC infusions improved systemic metabolic homeostasis and alleviated insulin resistance in EAT but elicited no change in weight. Despite rare engraftment of UC-MSCs in EAT, UC-MSC infusions attenuated insulin resistance in EAT by polarizing macrophages into the M2 phenotype, coupled with elevated serum IL-10 levels. In vivo blockade of IL-10 blunted the effects of UC-MSCs on obese mice. Furthermore, UC-MSCs overwhelmingly homed to the spleen, and the ability of UC-MSCs to elevate serum IL-10 levels and alleviate insulin resistance was impaired in the absence of the spleen. Further in vivo and in vitro studies revealed that UC-MSCs promoted the capacity of regulatory T cells (Treg cells) to produce IL-10 in the spleen. CONCLUSIONS: Our results demonstrated that UC-MSCs elevated serum IL-10 levels and subsequently promoted macrophage polarization, leading to alleviation of insulin resistance in EAT. The underlying mechanism was that UC-MSCs improved the capacity of Treg cells to produce IL-10 in the spleen. Our findings indicated that the spleen played a critical role in amplifying MSC-mediated immunomodulatory effects, which may contribute to maximizing MSC efficacy in clinical applications in the future.


Sujet(s)
Insulinorésistance , Transplantation de cellules souches mésenchymateuses , Cellules souches mésenchymateuses , Animaux , Alimentation riche en graisse/effets indésirables , Humains , Transplantation de cellules souches mésenchymateuses/méthodes , Souris , Souris obèse , Rate , Cordon ombilical
7.
Stem Cells Int ; 2021: 7435605, 2021.
Article de Anglais | MEDLINE | ID: mdl-34326879

RÉSUMÉ

OBJECTIVE: Accumulating evidence indicates that microRNAs (miRNAs) play crucial roles in osteogenic differentiation. However, the associated mechanisms remain elusive. This paper is aimed at exploring the role of miR-129-5p in regulating bone marrow mesenchymal stem cell (BMSC) differentiation and bone regeneration in vivo and in vitro. METHODS: BMSCs were transduced by miR-129-5p mimic, miR-129-5p inhibitor, and negative control lentivirus. The ability of BMSC differentiation to osteoblast was tested by alkaline phosphatase (ALP) and alizarin red staining (ARS). The expression of osteogenic genes (Runx2, Bmp2, and OCN) was examined via quantitative RT-PCR and western blot. A mouse model of calvaria defect was investigated by Micro-CT, immunohistochemistry, and histological examination. The luciferase reporter gene assay was performed to confirm the binding between Dkk3 and miR-129-5p. For the transfection experiments, lipofectamine 3000 was used to transfect pcDNA-Dkk3 into BMSCs to overexpress Dkk3. Coimmunoprecipitation and immunofluorescent localization assay were included for exploring the role of Dkk3 and ß-catenin. RESULTS: miR-129-5p was induced in BMSCs and MSC cell line C3H10T1/2 cells under osteogenic medium. Overexpression of miR-129-5p significantly promoted osteogenic differentiation of BMSCs in vitro. Moreover, BMSCs transduced with miR-129-5p mimic exhibited better bone regeneration compared with BMSCs transduced with control counterpart in vivo. Luciferase and western blot data showed that Dickkopf3 (Dkk3) is a target gene of miR-129-5p and the expression of Dkk3 was inhibited in BMSCs transduced with miR-129-5p mimic but enhanced in BMSCs transduced with miR-129-5p inhibitor. In addition, Dkk3 interacted with ß-catenin directly. CONCLUSIONS: miR-129-5p promotes osteogenic differentiation of BMSCs and bone regeneration, and miR-129-5p/Dkk3 axis may be new potential targets for the treatment of bone defect and bone loss.

8.
Ann Palliat Med ; 10(4): 4642-4651, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33966412

RÉSUMÉ

BACKGROUND: To evaluate the efficacy of pulsatile gonadotropin-releasing hormone (GnRH) therapy in patients with hypogonadism caused by hypopituitarism so as to guide clinical treatment. METHODS: Clinical manifestations, laboratory examinations, and imaging features were collected from 22 patients with hypopituitarism that led to hypogonadism who were treated with pulsatile GnRH. Data were analyzed and the patients were followed up. RESULTS: The average age at which patients began to use pulsatile GnRH was 22.8±3.7 years old. The duration of pulsatile GnRH administration ranged from 3 to 60 months, with an average of 20.5±12.1 months. The dosage of GnRH administered was 10-12 µg/90 minutes. Patients were followed up for 26-81 months, with an average of 50.5±17.3 months. After pulsatile GnRH treatment, the clinical manifestations and hormone levels of these patients improved to varying degrees. The luteinizing hormone (LH) and testosterone (T) levels of 7 patients increased to the normal range, sperm could be detected in seminal fluid samples of 5 patients, and 2 patients successfully reproduced. Within the good-response group, 71.4% of patients achieved spermatogenesis within an average of 13 months of treatment. In patients who had poor response to gonadotropin therapy prior to pulsatile GnRH therapy, 25% achieved spermatogenesis, and 37.5% reached the normal range of LH and T. The levels of LH after pulsatile GnRH treatment was positively correlated with the peak levels of LH and testicular volume prior to treatment (P<0.01). CONCLUSIONS: Pulsatile GnRH therapy can improve gonadal function in most patients with hypogonadism caused by hypopituitarism. Patients were able to achieve spermatogenesis, especially in patients who were poor-responders to gonadotropin treatment. Patients with greater basal testicular volume may respond better to pulsatile GnRH treatment. The GnRH stimulation test not only helps to evaluate the reserve function of pituitary GnRH cells at a certain time but may also serve as a prognostic factor. The results of this study form a basis for guiding clinical therapeutic choices.


Sujet(s)
Hypogonadisme , Hypopituitarisme , Adulte , Hormone de libération des gonadotrophines , Humains , Hypogonadisme/traitement médicamenteux , Hypogonadisme/étiologie , Hypopituitarisme/traitement médicamenteux , Hypopituitarisme/étiologie , Hormone lutéinisante , Mâle , Testicule , Jeune adulte
9.
Anal Chem ; 93(13): 5430-5436, 2021 04 06.
Article de Anglais | MEDLINE | ID: mdl-33760588

RÉSUMÉ

Nanopore-based detection techniques, with a wide range of transport properties, exhibit impressive selectivity and sensitivity for analytes. To expand the application of nanoporous sensors, real-time and fast detection of targets, all within a portable device, is highly desired for nanopore-based sensors. In addition, to improve the accuracy of the output signal, more appropriate readout methods also need to be explored. In this manuscript, we describe a nanopore-based electrode, regarded as NAC-P6-PC@AuE, prepared by coupling a pillararene-based nanoporous membrane with an electrochemical impedance measurement method. The fabricated device is demonstrated by exposing pillararene-based receptors to trace amounts of pesticide molecules. NAC-P6-PC@AuE devices exhibit distinguished selectivity to quinotrione, as well as the ability to quantify quinotrione with a limit of quantitation (LOQ) of 10 nM. The mechanism that allows sensing was verified using finite-element simulations and may be explained as host-guest-induced surface charge shielding, which influences the electrochemical response of probe molecules. The applications of this nanopore-based electrode may be extended toward other target molecules by decorating the nanopore surfaces with specifically chosen receptors.

12.
ACS Appl Bio Mater ; 3(2): 1226-1232, 2020 Feb 17.
Article de Anglais | MEDLINE | ID: mdl-35019323

RÉSUMÉ

Chiral-specific assembly is involved in many biochemical processes, such as DNA hybridization, protein adhesion, and sugar recognition. However, the signals of chiral interaction are usually very weak, and it is difficult to investigate the enantioselective behaviors. Therefore, it is necessary to construct the functional materials to regulate the selective behaviors of protein droplets via weak chiral interaction, which is also significant for the biological process of protein adhesive behaviors and proteinic drug delivery. Here, S- and R-amino alcohol derivative of calix[4]arene enantiomers (R/S-AC4) were synthesized and modified onto Au-surfaces to fabricate the enantiomer's materials and investigate the chiral selective adhesion of protein droplets. Through the experiment of fluorescence titration and molecular docking simulation, bovine serum albumin (BSA) showed the stronger interaction with R-amino alcohol-calix[4]arene than S-amino alcohol-calix[4]arene on the molecular level. Notably, the sliding angle showed that the droplet of BSA selectively adhered to the R-amino alcohol-calix[4]arene-modified surface, while it released rapidly from S-amino alcohol-calix[4]arene-modified surface by virtue of chiral selectivity. This result not only provides an easy and convenient model to regulate the selective adhesion and release of protein from chemical view, but also realizes the signal transduction through the weak chiral interaction.

13.
World J Clin Cases ; 7(8): 961-971, 2019 Apr 26.
Article de Anglais | MEDLINE | ID: mdl-31119141

RÉSUMÉ

BACKGROUND: Adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome (CS) is mostly due to unilateral tumors, with bilateral tumors rarely reported. Its common causes include primary pigmented nodular adrenocortical disease, ACTH-independent macronodular adrenal hyperplasia, and bilateral adrenocortical adenomas (BAAs) or carcinomas. BAAs causing ACTH-independent CS are rare; up to now, fewer than 40 BAA cases have been reported. The accurate diagnosis and evaluation of BAAs are critical for determining optimal treatment options. Adrenal vein sampling (AVS) is a good way to diagnose ACTH-independent CS. CASE SUMMARY: A 31-year-old woman had a typical appearance of CS. The oral glucose tolerance test showed impaired glucose tolerance and obviously increased insulin and C-peptide levels. Her baseline serum cortisol and urine free cortisol were elevated and did not show either a circadian rhythm or suppression with dexamethasone administration. The peripheral 1-deamino-8-D-arginine-vasopressin (DDVAP) stimulation test showed a delay of the peak level, which was 1.05 times as high as the baseline level. Bilateral AVS results suggested the possibility of BAAs. Abdominal computed tomography showed bilateral adrenal adenomas with atrophic adrenal glands (right: 3.1 cm × 2.0 cm × 1.9 cm; left: 2.2 cm × 1.9 cm × 2.1 cm). Magnetic resonance imaging of the pituitary gland demonstrated normal findings. A left adenomectomy by retroperitoneoscopy was performed first, followed by resection of the right-side adrenal mass 3 mo later. Biopsy results of both adenomas showed cortical tumors. Evaluations of ACTH and cortisol showed a significant decrease after left adenomectomy but could still not be suppressed, and the circadian rhythm was absent. Following bilateral adenomectomy, this patient has been administered with prednisone until now, all of her symptoms were alleviated, and she had normal blood pressure without edema in either of her lower extremities. CONCLUSION: BAAs causing ACTH-independent CS are rare. AVS is of great significance for obtaining information on the functional state of BAAs before surgery.

14.
Article de Anglais | MEDLINE | ID: mdl-31040822

RÉSUMÉ

Objective: To investigate the role of PSMA in the differential diagnosis of adrenocortical carcinoma samples (ACCs) and adrenocortical adenoma samples (ACAs), to validate the prognostic role of PSMA in patients with ACCs, and to explore the possibility that this marker can differentiate localized ACCs from adrenal metastases from other sites. Methods: PSMA protein expression in tissue samples from 50 ACCs, 90 ACAs (including 20 from patients who presented with Cushing's syndrome, 20 aldosterone-producing adenomas and 50 non-functional tumors) and 10 tissues that were metastases from other primary sites was assessed by immunohistochemistry. The clinical and pathological characteristics were compared, the intensity and density were analyzed, and the prognostic role was evaluated. Results: The analysis of clinical and pathological features revealed that the size of ACCs was greater than that of benign tissues and the ACC patients were older than the ACA patients (p < 0.01). The percentage of PSMA-positive vessels, the mean intensity and the degree of staining density were found to be significantly lower in ACAs than in ACCs (p < 0.01). In these 140 samples, 60% of the ACCs were grouped in the positive category. The samples were negative for metastases that were from other primary sites. The ENSAT stage and Ki-67 were correlated with PSMA expression. The survival distribution revealed that high PSMA expression did not show any prognostic relevance in the current ACCs series. Those samples with a score of > 3.5 were 75 times more likely to be malignant (OR = 75). We established a cut-off score of 3.5 (p < 0.05), which had 46% sensitivity and 99% specificity. Paralleling PSMA and Ki-67 maximized the area under the curve, with 72% sensitivity and 100% specificity. Conclusions: Our results strongly confirm that PSMA is helpful for distinguishing benign from malignant tumors and that its high expression levels correlate with a high ENSAT stage and high proliferation. The combination of PSMA and Ki-67 can be particularly useful. Furthermore, PSMA might be a useful tool for the identification of localized adrenal carcinoma and metastatic carcinoma.

15.
Front Neurol ; 9: 449, 2018.
Article de Anglais | MEDLINE | ID: mdl-29963005

RÉSUMÉ

Craniopharyngiomas and germinomas are both rare cranial tumors that most commonly present during childhood or adolescence. Although these tumors have different origins, their clinical and radiological features may be similar. In this article, we report the case of a 35-year female patient with clinical and radiological findings and increased human chorionic gonadotrophin (HCG) levels in the cerebrospinal fluid (CSF) that were consistent with a germinoma. However, pathological analysis revealed a craniopharyngioma. This case report indicates that HCG, which is regarded as a specific tumor marker for germinomas in the differential diagnosis of intracranial lesions, is also detectable in other kinds of suprasellar tumors, such as craniopharyngiomas.

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