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1.
Angew Chem Int Ed Engl ; : e202405671, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781001

RESUMO

Proteoglycans (PGs), consisting of glycosaminoglycans (GAGs) linked with the core protein through a tetrasaccharide linkage region, play roles in many important biological events. The chemical synthesis of PG glycopeptides is extremely challenging. In this work, the enzymes required for synthesis of chondroitin sulfate (CS) PG (CSPG) have been expressed and the suitable sequence of enzymatic reactions has been established. To expedite CSPG synthesis, the peptide acceptor was immobilized on solid phase and the glycan units were directly installed enzymatically onto the peptide. Subsequent enzymatic chain elongation and sulfation led to the successful synthesis of CSPG glycopeptides. The CS dodecasaccharide glycopeptide was the longest homogeneous CS glycopeptide synthesized to date. The enzymatic synthesis was much more efficient than the chemical synthesis of the corresponding CS glycopeptides, which could reduce the total number of synthetic steps by 80 %. The structures of the CS glycopeptides were confirmed by mass spectrometry analysis and NMR studies. In addition, the interactions between the CS glycopeptides and cathepsin G were studied. The sulfation of glycan chain was found to be important for binding with cathepsin G. This efficient chemoenzymatic strategy opens new avenues to investigate the structures and functions of PGs.

2.
J Genet Couns ; 32(4): 788-797, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36872635

RESUMO

Germline pathogenic variants of BRCA1 or BRCA2 cause hereditary breast and ovarian cancer syndromes. The present study investigated the participants' understanding and awareness of germline BRCA1/2 pathogenic variants before genetic counseling, the expectations and obstacles for genetic testing from the perspective of participants and their families, and their attitudes towards genetic testing after counseling. In this single-country, multicenter, non-interventional, patient-reported outcome study, untested cancer patients and their families who visited genetic counseling clinics or who wanted to receive pre-test genetic counseling were eligible to fill in the questionnaire after pre-test counseling for germline BRCA1/2 testing. Demographic information, clinical characteristics, and information collected from the questionnaires, including the understanding of BRCA1/2 pathogenic variants before genetic counseling, understanding of BRCA1/2 pathogenic variants and feelings after genetic counseling, willingness to share results of genetic testing with family, and willingness to receive genetic testing, were summarized using descriptive statistics. A total of 88 participants were enrolled. The proportion of slight understanding of BRCA1/2 pathogenic variants increased from 11.4% to 67.0%, and the proportion of full understanding increased from 0% to 8.0%. After genetic counseling, most participants were willing to undergo genetic testing (87.5%) and share the results with their families (96.6%). The main factors that may affect participants' willingness to undergo BRCA1/2 testing were management (61.2%) and testing costs (25.9%). After pre-test counseling, there was a high acceptance of BRCA1/2 testing and in-family information sharing in Taiwanese patients with cancer and their families, which may serve as a reference for implementing genetic counseling in Taiwan.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Feminino , Humanos , Proteína BRCA1/genética , Aconselhamento Genético , Predisposição Genética para Doença , Taiwan , Neoplasias Ovarianas/genética , Proteína BRCA2/genética , Testes Genéticos/métodos , Atitude , Neoplasias da Mama/genética
3.
Breast Cancer Res Treat ; 192(3): 629-637, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35113257

RESUMO

PURPOSE: Breast cancer is increasing around the globe, including Asia. We aimed to examine the survival and risk of contralateral breast cancer (CBC) in Asian breast cancer patients with BRCA mutations. METHODS: A total of 128 breast cancer patients with germline BRCA mutations and 4,754 control breast cancer patients were enrolled. Data on clinical-pathologic characteristics, survival, and CBC were collected from the medical record. The rates of survival and CBC were estimated by Kaplan-Meier method. RESULTS: The mean age of onset in BRCA mutation carriers was significantly younger than control patients (BRCA vs. Non-BRCA: 43.9 vs. 53.2 years old). BRCA mutation carriers had a higher proportion of triple-negative breast cancer (TNBC) (52%) than control patients (12%, p < 0.001). The risk of CBC was significantly higher in BRCA mutation patients than in control cases (hazard ratio (HR) = 3.95, 95% CI 2.71-5.75); when stratified by genotype, the HRs (95%CI) were 4.84 (3.00-7.82) for BRCA1 and 3.13 (1.78-5.49) for BRCA2 carriers, respectively. Moreover, BRCA1 mutation patients with triple-negative breast cancer (TNBC) as their first breast cancer had the highest risk of CBC (HR = 5.55, 95% CI 3.29-9.34). However, we did not observe any differences in relapse-free survival and overall survival between mutation carriers and control patients. CONCLUSION: Our study suggest that BRCA patients had a significantly higher risk of developing CBC, particularly for BRCA1 mutation carriers with TNBC as the first breast cancer.


Assuntos
Proteína BRCA1 , Proteína BRCA2 , Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Adulto , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Feminino , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade
4.
J Formos Med Assoc ; 121(12): 2538-2547, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35752529

RESUMO

BACKGROUND: The prognosis of triple-negative breast cancer (TNBC) is worse and a major proportion of TNBC expresses epidermal growth factor receptor (EGFR). Afatinib can inhibit EGFR signal pathway; however, its treatment effect for TNBC is unknown. Thus, we aimed to assess the efficacy and biomarkers of afatinib in combination with paclitaxel in a neoadjuvant setting. METHODS: Patients with stage II to III TNBC were enrolled. They received 40 mg of afatinib daily for 14 days, followed by daily afatinib and weekly paclitaxel (80 mg/m2) every 21 days for four to six cycles. To explore the mechanisms of responsiveness and non-responsiveness, 409 cancer-associated genes were sequenced. RESULTS: Twenty-one patients were enrolled and one patient achieved a complete clinical response; however, a 2 mm residual tumor was noted in the surgical specimen. Overall, 33.0% patients were responders. Fifteen patients received molecular testing. No activated mutation of EGFR or Her2 were found. Activated PI3K or JAK2 pathway were trended to associate with non-responder (p = 0.057). Mutation of homologous recombination (HR) genes were correlated with non-responsiveness (p = 0.005). Seven patients did not have altered PI3K, JAK2 or HR pathway; six (85.7%) of them were responder. Patients with the amplified DAXX gene was associated with a favorable trend of response (p = 0.109). CONCLUSION: Adding afatinib to neoadjuvant paclitaxel generated a modest effect in TNBC. Exploratory molecular analysis suggested that activated PI3K, JAK2 pathways and mutation of HR genes were associated with therapeutic non-responsiveness, and amplification of DAXX genes was associated with responsiveness to afatinib in combination with paclitaxel.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Terapia Neoadjuvante , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Paclitaxel/uso terapêutico , Afatinib/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fosfatidilinositol 3-Quinases/uso terapêutico , Resultado do Tratamento
5.
Chem Rec ; 21(12): 3498-3508, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33955155

RESUMO

Synthetic organic chemists endeavor to develop new reaction conditions, improve product yields, and enhance atom economy (synthetic methodologies), whereas the material scientists strive to create novel functional molecules/structures, increase device stabilities, and promote power conversion efficiencies via device engineering (organic optoelectronics). However, these two prominent research fields seem to have no intersections. Since joining national central university in 2012, our research philosophy aims to narrow, or rather to bridge the gap between synthetic methodologies and π-functional organic materials. In contrast to using multistep synthetic approaches based on Suzuki- or Stille coupling reactions, this personal account describes various step-saving and viable synthesis-shortcuts developed by our group, to access thiophene-based small molecules for optoelectronic applications. We expect these succinct and user-friendly alternative pathways designed by synthetic chemists would help material scientists to reach their target molecules in a more step-economical manner.


Assuntos
Estrutura Molecular , Humanos
6.
Org Biomol Chem ; 19(15): 3374-3378, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33899899

RESUMO

Proteoglycans (PGs) play important roles in many biological processes including tumor progression, cell adhesion, and regulation of growth factor activities. With glycosaminoglycan chains attached to the core proteins in nature, PGs are highly challenging synthetic targets due to the difficulties in integrating the sulfated glycans with the peptide backbone. To expedite the synthesis, herein, the utility of human xylosyltransferase I (XT-I), the enzyme responsible for initiating PG synthesis, has been explored. XT-I was found to be capable of efficiently installing the xylose unit onto a variety of peptide structures on mg scales. Furthermore, an unnatural sugar, i.e., 6-azidoglucose can be transferred by XT-I introducing a reactive handle onto the glycopeptide for selective functionalization. XT-I can be coupled with ß-4-galactosyl transferase-7 for one pot synthesis of glycopeptides bearing galactose-xylose disaccharide, paving the way toward efficient chemoenzymatic synthesis of PG glycopeptides and glycoproteins.


Assuntos
Pentosiltransferases/metabolismo , Proteoglicanas/biossíntese , Humanos , Conformação Proteica , Proteoglicanas/química , UDP Xilose-Proteína Xilosiltransferase
7.
Sensors (Basel) ; 21(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802547

RESUMO

Coordinated Multi-Point (CoMP) is an important technique in B4G/5G networks. With CoMP, multiple base stations can be clustered to compose a cooperating set to improve system throughput, especially for the users in cell edges. Existed studies have discussed how to mitigate overloading scenarios and enhance system throughput with CoMP statically. However, static cooperation fixes the set size and neglects the fast-changing of B4G/5G networks. Thus, this paper provides a full study of off-peak hours and overloading scenarios. During off-peak hours, we propose to reduce BSs' transmission power and use the free radio resource to save energy while guaranteeing users' QoS. In addition, if large-scale activities happen with crowds gathering or in peak hours, we dynamically compose the cooperating set based on instant traffic requests to adjust base stations' BSs' transmission power; thus, the system will efficiently offload the traffic to the member cells which have available radio resources in the cooperating set. Experimental results show that the proposed schemes enhance system throughput, radio resource utilization, and energy efficiency, compared to other existing schemes.

8.
Cancer Sci ; 111(4): 1375-1384, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31958182

RESUMO

BRCAness is considered a predictive biomarker to platinum and poly(ADP-ribose) polymerase (PARP) inhibitors. However, recent trials showed that its predictive value was limited in triple-negative breast cancer (TNBC) treated with platinum. Moreover, tumors with mutations of DNA damage response (DDR) genes, such as homologous recombination (HR) genes, could be sensitive to platinum and PARP inhibitors. Thus, we aim to explore the relationship between mutation status of DDR genes and BRCAness in TNBC. We sequenced 56 DDR genes in 120 TNBC and identified BRCAness by array comparative genomic hybridization. The sequencing results showed that 13, 14, and 14 patients had BRCA, non-BRCA HR, and non-HR DDR gene mutations, respectively. Array comparative genomic hybridization revealed that BRCA-mutated and HR gene-mutated TNBC shared similar BRCAness features, both having higher numbers and longer length of large-scale structural aberration (LSA, >10 Mb) and similar altered chromosomal regions of LSA. These suggested non-BRCA HR gene-mutated TNBC shared similar characteristics with BRCA-mutated TNBC, indicating non-BRCA HR gene-mutated TNBC sensitive to platinum and PARP inhibitors. Among tumors with mutation of non-HR DDR genes, 3 PTEN and 1 MSH6 mutation also contained significant LSAs (BRCAness); however, they had different regions of genomic alteration to BRCA and HR gene-mutated tumors, might explain prior findings that PTEN- and MSH6-mutated cancer cells not sensitive to PARP inhibitors. Therefore, we hypothesize that the heterogeneous genomic background of BRCAness indicates different responsiveness to platinum and PARP inhibitors. Direct sequencing DDR genes in TNBC should be applied to predict their sensitivity toward platinum and PARP inhibitors.


Assuntos
Dano ao DNA/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Recombinação Homóloga/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Proteína BRCA1/genética , Proteína BRCA2/genética , Dano ao DNA/genética , Feminino , Humanos , Pessoa de Meia-Idade , Mutação/genética , Platina/administração & dosagem , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteína Supressora de Tumor p53/genética
9.
J Pineal Res ; 68(1): e12620, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31710386

RESUMO

The circadian nature of melatonin has a protective effect on the progression of female reproductive cancers, including breast and ovarian cancers. However, the effect of melatonin on the growth of uterine leiomyoma is still unclear. In this study, we found that the growth of uterine leiomyoma ELT3 cells was reduced by treatment with melatonin. Treatment with melatonin increased the distribution of sub-G1 phase and increased DNA condensation in ELT3 cells. Melatonin-induced apoptosis and autophagy cell death progression were observed in ELT3 cells. Melatonin exerts a highly selective effect on primary normal human uterine smooth muscle (UtSMC) cells. The UtSMC cell cycle was arrested by melatonin treatment through up-regulation of p21, p27, and PTEN protein expression, but melatonin did not further promote apoptosis program activation. Melatonin reduced cell proliferation in ELT3 cells underlying the activation of melatonin MT1 and MT2 receptors, which in turn down-regulated the Akt-ERK1/2-NFκB signaling pathway. Melatonin reduced ELT3 tumor growth in both xenograft and orthotopic uterine tumor mice models. The extracellular matrix of the tumor was also reduced by melatonin treatment. Taken together, these results suggest that melatonin potentially plays a role in suppression of uterine leiomyoma growth.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Leiomioma/metabolismo , Melatonina/farmacologia , Neoplasias Uterinas/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos , Ratos , Útero/citologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Dig Dis Sci ; 65(11): 3408-3409, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32990865

RESUMO

The original version of the article unfortunately contained an error in the legend of Figure 5B. Corrected version of Figure 5 is given below.

11.
Dig Dis Sci ; 65(10): 2834-2843, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31897897

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS), a common hormonal disorder in women, affects 4-18% of women of reproductive age worldwide. A higher prevalence of irritable bowel syndrome was found in women with PCOS. However, the effects and mechanism of PCOS on stomach and colon contractility remain unclear. AIMS: This study aims to evaluate the correlation between PCOS and gastrointestinal disorder. METHODS: Four-week-old female rats were subcutaneously implanted with pellets containing 7.5 mg of dihydrotestosterone for 13 weeks to create PCOS rat models. After vaginal smears, the estrus cycle stage was evaluated. Oral glucose tolerance test was performed after 90 days of treatment. All animals were killed at 17 weeks. The rats were fasted overnight and then anesthetized before decapitation, and the stomach fundus and colon were surgically removed and cultured in oxygenated Krebs solution. Acetylcholine and carbachol were used to evaluate the cholinergic system on contractility. RESULTS: The basal and stomach fundus responded with a reduced frequency and contractility in response to acetylcholine in the PCOS group. Moreover, no difference was found in the spontaneous stomach contractility induced by carbachol in both groups. Lower maximal colon muscle contractility was also found in response to acetylcholine stimulation in PCOS rats. Furthermore, lower maximal muscle contractility was found in response to extracellular calcium levels. MLC20 phosphorylation was also reduced in the gastrointestinal tissue in PCOS rats. CONCLUSIONS: PCOS induces gastroparesis and reduces gastrointestinal muscle contractility. This effect is, at least partly, through reducing the responsiveness of acetylcholine and MLC20 phosphorylation.


Assuntos
Colo/fisiopatologia , Gastroenteropatias/fisiopatologia , Motilidade Gastrointestinal , Contração Muscular , Músculo Liso/fisiopatologia , Síndrome do Ovário Policístico/complicações , Estômago/fisiopatologia , Acetilcolina/farmacologia , Animais , Sinalização do Cálcio , Carbacol/farmacologia , Colo/efeitos dos fármacos , Colo/metabolismo , Di-Hidrotestosterona , Modelos Animais de Doenças , Feminino , Gastroenteropatias/etiologia , Gastroenteropatias/metabolismo , Motilidade Gastrointestinal/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Cadeias Leves de Miosina/metabolismo , Fosforilação , Síndrome do Ovário Policístico/induzido quimicamente , Ratos Sprague-Dawley , Estômago/efeitos dos fármacos
12.
Am J Occup Ther ; 74(4): 7404205050p1-7404205050p9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32602444

RESUMO

IMPORTANCE: A psychometrically sound measure of social knowledge (SK) is necessary to assess people with schizophrenia because they tend to have moderate to severe deficits in SK. OBJECTIVE: To develop a computerized adaptive test (CAT) for assessing SK in people with schizophrenia. DESIGN: Two phases, consisting of (1) development and validation of an SK item bank and (2) determination of the best stopping rules for the CAT. SETTING: Two psychiatric hospitals. PARTICIPANTS: Two hundred thirty-six people diagnosed with schizophrenia through convenience sampling. MEASURE: Computerized Adaptive Test-Social Knowledge (CAT-SK). RESULTS: The SK items were examined using Rasch analysis. A CAT simulation was performed to determine the best set of stopping rules for achieving high reliability and efficiency. After unsuitable items were removed, 71 items remained with acceptable model fit (infit and outfit mean square <1.4) and no gender bias. Two suboptimal alternative sets of rules were identified. The most efficient set used 21 items to achieve acceptable Rasch reliability (.81). The most reliable set used 40 items to achieve satisfactory Rasch reliability (.88). High correlations (r > .93) between CAT-SK scores and scores on the SK item bank support the concurrent validity of the CAT-SK. CONCLUSIONS AND RELEVANCE: The CAT-SK appears to be a valid assessment that can provide reliable or efficient measures of SK. If high reliability is needed, examiners can adopt the most reliable set of 40 items. If efficiency is the primary concern, they can adopt the most efficient set of 21 items. WHAT THIS ARTICLE ADDS: The CAT-SK is a valid measure of SK with flexibility to meet examiners' needs.


Assuntos
Avaliação da Deficiência , Esquizofrenia , Humanos , Psicometria , Reprodutibilidade dos Testes
13.
Mar Drugs ; 17(6)2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185695

RESUMO

The purpose of this study was to investigate the preventive effects of fucoidan (Fc) and fucoxanthin (Fx) on hyperuricemic rats. Sprague Dawley (SD) rats were randomly assigned to seven groups: a control group, a hyperuricemia (HUA) group, low- and high-dose Fx groups, a Fc group, a combination Fc and Fx group, and a positive control group. Three weeks after the interventions, each group was given potassium oxonate (PO) and hypoxanthine (HX) to induce HUA in all groups except for the control group, and the rats were then sacrificed. Blood and urine were analyzed for biochemical properties, and differences in urine volume were determined. Livers and kidneys were collected to analyze xanthine oxidase (XO) activity and the expression of uric acid (UA) transporter-related proteins (GLUT9, ABCG2, OAT1, URAT1). The results show that HUA was successfully induced by PO/HX after 4 h of administration. The activity of XO was significantly reduced by a combination of Fc and Fx. In the combination group, both ABCG2 and OAT1 increased significantly, whereas GLUT9 and URAT1 decreased significantly. In summary, the combination of Fc and Fx can inhibit the activity of XO in the liver and regulate the expression of proteins related to UA transporter in the kidney to reduce the UA level in serum.


Assuntos
Hiperuricemia/induzido quimicamente , Ácido Oxônico , Polissacarídeos/farmacologia , Xantofilas/farmacologia , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Hiperuricemia/tratamento farmacológico , Rim/efeitos dos fármacos , Rim/enzimologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Polissacarídeos/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Xantina Oxidase/metabolismo , Xantofilas/uso terapêutico
14.
Molecules ; 24(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010220

RESUMO

Uterine leiomyomas, also known as fibroids, are benign neoplasms of the uterus and have a high incidence rate in women of reproductive age. Hysterectomy or myomectomy is the initial treatment, but fibroids will recur if the patient is still exposed to similar risk factors. Therefore, developing new therapeutic strategies are urgently necessary. In this study, the anti-proliferation effects of each fraction of adlay seeds were evaluated in uterine leiomyomas, and we identified the potential phytochemical compounds. We found that the ethyl acetate fraction of adlay hull (AHE-ea) appeared to be highly efficient in the anti-proliferation of rat uterine leiomyoma ELT3 cells and primary human uterine leiomyoma (hUL) cells. The proliferation of primary human normal uterine smooth muscle (UtSMC) and normal uterine myometrial (hUM) cells were also suppressed by AHE-ea. Two phytosterols, stigmasterol and ß-sitosterol, were identified from AHE-ea fraction. Mice treated with AHE-ea and stigmasterol alone demonstrated reduced diethylstilbestrol/medroxyprogesterone 17-acetate (DES/MPA)-induced uterine myometrial hyperplasia, which is the critical step for the development of leiomyoma. Taken together, our results suggest that the AHE-ea fraction could be considered as a natural plant-based medicine in the prevention or treatment of uterine leiomyoma growth.


Assuntos
Coix/química , Leiomioma/prevenção & controle , Extratos Vegetais/uso terapêutico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dietilestilbestrol/toxicidade , Feminino , Humanos , Leiomioma/tratamento farmacológico , Acetato de Medroxiprogesterona/toxicidade , Camundongos , Fosforilação , Ratos , Neoplasias Uterinas/induzido quimicamente , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/prevenção & controle
15.
J Cell Physiol ; 232(8): 2135-2144, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27886378

RESUMO

The increasing intensity of exercise enhanced corticosterone and lactate production in both humans and rodents. Our previous studies also demonstrated that lactate could stimulate testosterone production in vivo and in vitro. However, the production of testosterone in response to combined corticosterone and lactate on Leydig cells, and underlying molecular mechanisms are remained unclear. This study investigated the changes in testosterone levels of Leydig cells upon exposure to lactate, corticosterone or combination of both, and revealed the detailed mechanisms. Leydig cells were isolated from rat testes, and treated with different concentrations of lactate (2.5-20 mM), cortiosterone (10-9 -10-4 M) and lactate plus corticosterone. The production of testosterone were assayed by radioimmunoassay, and the key molecular proteins, including luteinizing hormone receptor (LHR), protein kinase A (PKA), steroidogenic acute regulatory protein (StAR), and cholesterol P450 side-chain cleavage enzyme (P450scc) involved in testosterone production were performed by Western blot. Results showed that testosterone levels were significantly increased with lactate, while decresed with corticosterone and lactate plus corticosterone treatment. Protein expressions of LHR and P450scc were upregulated with lactate treatment. However, PKA and P450scc were downregulated by lactate plus corticosterone treatment. This downregulation was followed by decreased testoterone levels in Leydig cells. Furthermore, acetylated cAMP, which activates testosterone production was increased with lactate, but not altered by conrtiosterone. Our findings conclude that corticosterone may interfere with lactate, and restrict lactate-stimulated testosterone production in Leydig cells. J. Cell. Physiol. 232: 2135-2144, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Corticosterona/farmacologia , Ácido Láctico/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Testosterona/metabolismo , Animais , Células Cultivadas , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Células Intersticiais do Testículo/metabolismo , Masculino , Ratos Sprague-Dawley , Receptores do LH/efeitos dos fármacos , Receptores do LH/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos
16.
J Org Chem ; 82(7): 3538-3551, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28266844

RESUMO

A variety of push-pull type organic dyes are facilely synthesized through the most atom-economical C-H/C-H dehydrogenative coupling reactions. After comprehensive synthetic optimizations, a broad substrate scope is achieved and functional groups, such as ester, ketone, nitrile, nitro, and triazene are well tolerated. The sensitive aldehyde group required for the conversion into anchoring groups for DSSCs applications is also compatible under present oxidant-containing reaction conditions. Based on this optimum C-H/C-H coupling approach, three new organic sensitizers are readily prepared and submitted to solar cell device fabrications, giving the power conversion efficiency (PCE) up to 4.85%. This work constitutes the first example that connects high atom-efficiency C-H/C-H green catalysis with dye-sensitized solar cell applications.

17.
Chemistry ; 21(24): 8754-7, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25925608

RESUMO

In contrast to the traditional multistep synthesis, herein an efficient and fewer-steps new synthetic strategy is demonstrated for the facile preparation of organic-electronically important D-π-A-π-D-type oligoaryls through sequential direct CH arylations. This methodology has shown that the synthesis of thieno[3,4-c]pyrrole-4,6-dione (TPD)- or furano[3,4-c]pyrrole-4,6-dione (FPD)-centred target molecules could be accessed step-economically either from the core structure (acceptor) or from the end structure (donor), which supplied a more flexible and succinct new synthetic alternative to the preparation of the π-functional small-molecule semiconducting materials. In addition, optical and electrochemical properties of the synthesized oligoaryls were examined.

18.
Support Care Cancer ; 22(5): 1199-206, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24317849

RESUMO

PURPOSE: The primary aim of this study was to evaluate the efficacy of palonosetron combined with dexamethasone in the prevention of vomiting, and especially nausea, in patients receiving allogeneic stem cell transplantation. METHODS: Palonosetron 0.25 mg was given to 27 patients receiving allogeneic transplantation on the first day of conditioning, and then every other day during the entire conditioning period. Dexamethasone was given daily also during conditioning. Vomiting and nausea were recorded daily according to CTCAE version 4.0 from the start of conditioning to Day 7 after transplantation. In addition, MASCC antiemetic tool (MAT) was also used in parallel to evaluate the intensity of nausea. RESULTS: The treatment was well tolerated; 25.9 and 40.7 % of the patients had grade 2/3 vomiting and nausea respectively during conditioning. The incidences of grade 2/3 vomiting and nausea were even higher in the first week after transplantation (40.7 and 51.8 %, respectively). The score of MAT correlated well with the grade of CTCAE. However, the difference in the mean intensity of nausea between period of conditioning and the first week after HSCT was significant only by using MAT (0.96 ± 1.829 vs. 3.81 ± 3.386, p=0.001) but not CTCAE (1.26 ± 0.903 vs. 1.63 ±0.967, p=0.152). CONCLUSION: Palonosetron combined with dexamethasone is effective in preventing vomiting during conditioning. However, more effort should be made to alleviate nausea during conditioning and both nausea and vomiting in the first week after transplantation. Furthermore, MAT has a higher discriminant power than CTCAE in assessing the intensity of nausea in patients receiving allogeneic transplantation.


Assuntos
Antieméticos/uso terapêutico , Dexametasona/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Isoquinolinas/uso terapêutico , Náusea/prevenção & controle , Quinuclidinas/uso terapêutico , Condicionamento Pré-Transplante/efeitos adversos , Vômito/prevenção & controle , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bussulfano/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Palonossetrom , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Vômito/etiologia , Adulto Jovem
19.
J Chem Phys ; 140(20): 204504, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24880298

RESUMO

We have investigated the properties of vapor-deposited glasses prepared from short polymer chains using molecular dynamics simulations. Vapor-deposited polymer glasses are found to have higher density and higher kinetic stability than ordinary glasses prepared by gradual cooling of the corresponding equilibrium liquid. In contrast to results for binary Lennard-Jones glasses, the deposition rate is found to play an important role in the stability of polymer vapor-deposited glasses. Glasses deposited at the slowest deposition rate and at the optimal substrate temperature are found to correspond to the ordinary glasses that one could hypothetically prepare by cooling the liquid at rates that are 4-5 orders of magnitude slower than those accessible in the current simulations. For intermediate-length polymer chains, the resulting vapor-deposited glasses are found to be highly anisotropic. For short chains, however, the glasses are isotropic, showing that structural anisotropy is not a necessary condition for formation of stable glasses by physical vapor deposition.


Assuntos
Anisotropia , Vidro/química , Polímeros/química , Gases , Cinética , Simulação de Dinâmica Molecular , Propriedades de Superfície , Termodinâmica
20.
ACS Nano ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012271

RESUMO

The edges of 2D materials have emerged as promising electrochemical catalyst systems, yet their performance still lags behind that of noble metals. Here, we demonstrate the potential of oriented electric fields (OEFs) to enhance the electrochemical activity of 2D materials edges. By atomically engineering the edge of a fluorographene/graphene/MoS2 heterojunction nanoribbon, strong and localized OEFs were realized as confirmed by simulations and spatially resolved spectroscopy. The observed fringing OEF results in an enhancement of the heterogeneous charge transfer rate between the edge and the electrolyte by 2 orders of magnitude according to impedance spectroscopy. Ab initio calculations indicate a field-induced decrease in the reactant adsorption energy as the origin of this improvement. We apply the OEF-enhanced edge reactivity to hydrogen evolution reactions (HER) and observe a significantly enhanced electrochemical performance, as evidenced by a 30% decrease in Tafel slope and a 3-fold enhanced turnover frequency. Our findings demonstrate the potential of OEFs for tailoring the catalytic properties of 2D material edges toward future complex reactions.

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