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1.
J Am Chem Soc ; 146(13): 9084-9095, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38428016

RESUMO

Isotactic polymers have emerged with unique and excellent properties in material sciences. Specific discrimination polymerization provides an ideal pathway to achieve highly isotactic polymers from their racemic monomers, which is of great significance and a challenge in polymeric chemistry. Although an enantioselective catalyst-mediated asymmetric kinetic resolution polymerization (AKRP) process makes it possible, a general and well-defined strategy for catalyst design is still rarely reported. Here, based on a novel dual-ligand strategy, a new type of chiral (BisSalen)Al complex with high enantioselectivity has been described, in which perfect AKRP of racemic phenethylglycolide (Pegl) is achieved for the first time. The more confined asymmetric microenvironment formed by a dual ligand is the key to improve the enantioselectivity of the original catalyst. To illustrate the generality of this strategy, a series of (BisSalen)Al complexes with homo- or heterodual ligands were designed for the AKRP of Pegl.

2.
Molecules ; 29(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38338384

RESUMO

The accumulation of waste plastics has a severe impact on the environment, and therefore, the development of efficient chemical recycling methods has become an extremely important task. In this regard, a new strategy of degradation product-promoted depolymerization process was proposed. Using N,N'-dimethyl-ethylenediamine (DMEDA) as a depolymerization reagent, an efficient chemical recycling of poly(bisphenol A carbonate) (BPA-PC or PC) material was achieved under mild conditions. The degradation product 1,3-dimethyl-2-imidazolidinone (DMI) was proven to be a critical factor in facilitating the depolymerization process. This strategy does not require catalysts or auxiliary solvents, making it a truly green process. This method improves the recycling efficiency of PC and promotes the development of plastic reutilization.

3.
Front Oncol ; 14: 1329133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384812

RESUMO

Previous studies have shown that the risk of malignant transformation of endometriosis in premenopausal women is approximately 1%, significantly impacting the overall well-being and quality of life of affected women. Presently, the diagnostic gold standard for endometriosis-associated ovarian cancer (EAOC) continues to be invasive laparoscopy followed by histological examination. However, the application of this technique is limited due to its high cost, highlighting the importance of identifying a non-invasive diagnostic approach. Therefore, there is a critical need to explore non-invasive diagnostic methods to improve diagnostic precision and optimize clinical outcomes for patients. This review presents a comprehensive survey of the current progress in comprehending the pathogenesis of malignant transformation in endometriosis. Furthermore, it examines the most recent research discoveries concerning the diagnosis of EAOC and emphasizes potential targets for therapeutic intervention. The ultimate objective is to improve prevention, early detection, precise diagnosis, and treatment approaches, thereby optimizing the clinical outcomes for patients.

4.
J Cell Mol Med ; 28(2): e18034, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37942713

RESUMO

Fulminant myocarditis (FM) is the most serious type of myocarditis. However, the molecular mechanism underlying the pathogenesis of FM has not been fully elucidated. Small extracellular vesicles (sEVs) play important roles in many diseases, but any potential role in paediatric FM has not been reported. Here, the differential signatures of lncRNAs in plasma sEVs were studied in FM children and healthy children using transcriptome sequencing followed by functional analysis. Then immune-related lncRNAs were screened to study their role in immune mechanisms, the levels and clinical relevance of core immune-related lncRNAs were verified by qRT-PCR in a large sample size. Sixty-eight lncRNAs had increased levels of plasma sEVs in children with FM and 11 had decreased levels. Functional analysis showed that the sEVs-lncRNAs with different levels were mainly related to immunity, apoptosis and protein efflux. Seventeen core immune-related sEVs-lncRNAs were screened, functional enrichment analysis showed that these lncRNAs were closely related to immune activation, immune cell migration and cytokine pathway signal transduction. The results of the study show that sEVs-lncRNAs may play an important role in the pathogenesis of fulminant myocarditis in children, especially in the mechanism of immune regulation.


Assuntos
Vesículas Extracelulares , Miocardite , RNA Longo não Codificante , Humanos , Criança , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Miocardite/genética , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Transdução de Sinais/genética , Citocinas
5.
Front Genet ; 14: 1275154, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028615

RESUMO

Ovarian cancer affects the female reproductive system and is the primary cause of cancer related mortality globally. The imprecise and non-specific nature of ovarian cancer symptoms often results in patients being diagnosed at an advanced stage, with metastatic lesions extending beyond the ovary. This presents a significant clinical challenge and imposes a substantial economic burden on both patients and society. Despite advancements in surgery, chemotherapy, and immunotherapy, the prognosis for most patients with ovarian cancer remains unsatisfactory. Therefore, the development of novel treatment strategies is imperative. Ferroptosis, a distinct form of regulated cell death, characterized by iron-dependent lipid peroxidation, differs from autophagy, apoptosis, and necrosis, and may hold promise as a novel cell death. Numerous studies have demonstrated the involvement of ferroptosis in various conventional signaling pathways and biological processes. Recent investigations have revealed the significant contribution of ferroptosis in the initiation, progression, and metastasis of diverse malignant tumors, including ovarian cancer. Moreover, ferroptosis exhibits a synergistic effect with chemotherapy, radiotherapy, and immunotherapy in restraining the proliferation of ovarian cancer cells. The aforementioned implies that ferroptosis holds considerable importance in the management of ovarian cancer and has the potential to serve as a novel therapeutic target. The present review provides a comprehensive overview of the salient features of ferroptosis, encompassing its underlying mechanisms and functional role in ovarian cancer, along with the associated signaling pathways and genes. Furthermore, the review highlights the prospective utility of ferroptosis in the treatment of ovarian cancer.

6.
Arch Biochem Biophys ; 745: 109716, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37553047

RESUMO

For a considerable duration, cervical cancer has posed a significant risk to the well-being and survival of women. The emergence and progression of cervical cancer have garnered extensive attention, with prolonged chronic infection of HPV serving as a crucial etiological factor. Consequently, investigating the molecular mechanism underlying HPV-induced cervical cancer has become a prominent research area. The HPV molecule is composed of a long control region (LCR), an early coding region and a late coding region.The early coding region encompasses E1, E2, E4, E5, E6, E7, while the late coding region comprises L1 and L2 ORF.The investigation into the molecular structure and function of HPV has garnered significant attention, with the aim of elucidating the carcinogenic mechanism of HPV and identifying potential targets for the treatment of cervical cancer. Research has demonstrated that the HPV gene and its encoded protein play a crucial role in the invasion and malignant transformation of host cells. Consequently, understanding the function of HPV oncoprotein is of paramount importance in comprehending the pathogenesis of cervical cancer. E6 and E7, the primary HPV oncogenic proteins, have been the subject of extensive study. Moreover, a number of contemporary investigations have demonstrated the significant involvement of HPV16 E5 oncoprotein in the malignant conversion of healthy cells through its regulation of cell proliferation, differentiation, and apoptosis via diverse pathways, albeit the precise molecular mechanism remains unclear. This manuscript aims to provide a comprehensive account of the molecular structure and life cycle of HPV.The HPV E5 oncoprotein mechanism modulates cellular processes such as proliferation, differentiation, apoptosis, and energy metabolism through its interaction with cell growth factor receptors and other cellular proteins. This mechanism is crucial for the survival, adhesion, migration, and invasion of tumor cells in the early stages of carcinogenesis. Recent studies have identified the HPV E5 oncoprotein as a promising therapeutic target for early-stage cervical cancer, thus offering a novel approach for treatment.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/genética , Carcinogênese
7.
Chem Asian J ; 17(20): e202200667, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-35983673

RESUMO

As a petroleum-derived polyester material, poly(ϵ-caprolactone) (PCL) plays an essential role in biomedical field due to its excellent biocompatibility and non-toxicity. With the increasing use of PCL in recent years, its waste disposal has become a significant challenge. To address this challenge, we demonstrate a high-efficiency organocatalysis strategy for the chemical upcycling of PCL to valuable chemical. Among organocatalysts explored in this article, 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) shows superior performance for transforming end-of-life poly(ϵ-caprolactone) into highly value-added methyl 6-hydroxyhexanoate with quantitative conversion in a short time. The endwise unzipping depolymerization mechanism is corroborated by monitoring molecular weight during depolymerization process and 1 H NMR control experiments. Furthermore, this approach is also practicable for large-scale depolymerization for commercial PCL plastics, providing idea for promoting the sustainable development of PCL plastics.


Assuntos
Petróleo , Poliésteres , Poliésteres/química , Plásticos , Catálise
8.
Biomed Pharmacother ; 117: 109173, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387176

RESUMO

Due to the success of chimeric antigen receptors (CARs) in hematological tumors, CARs are also being studied to treat solid tumors. Improving the ability of CARs to penetrate solid tumor tissues is one of the biggest challenges. As the most malignant cancer of the female reproductive system, the survival rate of ovarian cancer has not been significantly improved by traditional therapy methods; therefore, it is necessary to develop new therapeutic targets and new immunotherapy methods for ovarian cancer. UPAR is a glysocylphosphatidylinositol (GPI) anchoring membrane protein that is differentially expressed in normal tissues and ovarian cancer tissues. It has been shown that uPAR up-regulation promotes tumor development, proliferation, invasion, and metastasis, and uPAR is also up-regulated in tumor matrix components. In our study, CARs were designed using the natural ligand binding fragment of uPAR for ovarian cancer.


Assuntos
Proteínas de Membrana/metabolismo , Neoplasias Ovarianas/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Adulto , Idoso , Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Imunoterapia/métodos , Pessoa de Meia-Idade , Metástase Neoplásica/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/terapia , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
9.
Oncol Lett ; 11(4): 2865-2868, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27073566

RESUMO

Cotyledonoid dissecting leiomyoma (CDL), also termed Sternberg tumor, is a variant of uterine leiomyoma that is rarely diagnosed by clinical evaluation. At present, ~43 cases of CDL have been reported in the literature written in the English language. Due to the distinctive grapelike gross appearance of an exophytic mass resembles placental tissue, CDL is often misdiagnosed clinically as an ovarian tumor or uterine sarcoma. Therefore, an awareness of the features of the disease is important to prevent misdiagnosis and overtreatment. The present study reports 4 cases of CDL of the uterus that were treated at the Second Hospital of Jilin University between January 2009 and December 2011. All 4 patients in the current study presented with a palpable asymptomatic pelvic mass, which was detected during physical examinations, and cancer antigen 125 tumor marker levels that were within the normal range. The exploratory laparotomy of the 4 patients revealed lobulated tumors with a grapelike appearance extending from the lateral uterine wall into the ligament or the adjacent tissues. The frozen section and postoperative pathology were diagnosed as CDL. A total abdominal hysterectomy was performed in the first case of a 55-year-old woman that had been in menopause for 7 years. The patient was well and showed no evidence of disease subsequent to 48 months of follow-up. A total abdominal hysterectomy and right salpingo-oophorectomy were performed in the second case of a 43-year-old woman, who was well and showed no evidence of disease subsequent to 26 months of follow-up. A subtotal abdominal hysterectomy and bilateral salpingectomy were performed in the third case of a 37-year-old woman, who was well and showed no evidence of disease subsequent to 27 months of follow-up. A total abdominal hysterectomy and right-salpingectomy were performed with the removal of a retroperitoneal fibroid extension in the fourth case of a 48-year-old woman, who was well and showed no evidence of disease subsequent to 32 months of follow-up.

10.
Oncol Lett ; 9(2): 717-720, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25621042

RESUMO

Leiomyomatosis peritonealis disseminata (LPD) is a specific type of leiomyomatosis with an unclear pathogenesis that is rarely diagnosed by clinical evaluation. To date, <200 cases have been reported. The majority of the patients have a medical history of laparoscopic myomectomy for uterine fibroids. The use of laparoscopic power morcellation may be a contributor to the development of LPD, therefore, the specific surgical approach used in laparoscopic myomectomy should be carefully considered, and protective measures should be taken to prevent myoma fragments spreading if laparoscopic power morcellation is used. The present study reviewed and analyzed the medical history, diagnostic process and treatment strategy of a case of LPD to improve our understanding of the disease. In this report, the case of a 34 year-old female who underwent laparoscopic myomectomy to remove a uterine fibroid is presented. During the surgery, a myoma was resected using morcellators. Three years after surgery, exploratory laparotomy was performed due to uterine fibroid recurrence. During surgery, myoma was identified at the uterine bladder peritoneal reflection, where several unequally sized leiomyoma tubercles were identified on the uterine surface. Subsequently, myomectomy was performed. Postoperative pathology diagnosed leiomyoma. Two years later, gynecological ultrasound revealed a mass in the abdomen. Exploratory laparotomy was subsequently performed. During surgery, compact myoma tubercle-like cysts were identified on the surface of the intestine and mesentery, and an endometriotic cyst was identified on the left ovary. As the myomas were too compact to remove completely, the majority of leiomyoma on the intestine and mesentery was resected. The endometriotic cyst on the left ovary was also resected. Considering the patient's medical history, observations during surgery and pathological results, the final diagnosis was LPD. Following surgery, the patient was treated with the gonadotropin-releasing hormone agonist, triptorelin acetate (3.5 mg, once every four weeks), for three months and followed-up every six months. In October 2014, a gynecological sonography examination revealed no abnormalities and at the time of writing, the patient remains alive and well.

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