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1.
J Am Chem Soc ; 145(44): 23939-23947, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37748140

RESUMO

Autophagy is responsible for the degradation of large intracellular contents, such as unwanted protein aggregates and organelles. Impaired autophagy can therefore lead to the accumulation of pathological aggregates, correlating with aging and neurodegenerative diseases. However, a broadly applicable methodology is not available for the targeted degradation of protein aggregates or organelles in mammalian cells. Herein, we developed a series of autophagy receptor-inspired targeting chimeras (AceTACs) that can induce the targeted degradation of aggregation-prone proteins and protein aggregates (e.g., huntingtin, TDP-43, and FUS mutants), as well as organelles (e.g., mitochondria, peroxisomes, and endoplasmic reticulum). These antibody-fusion-based AceTAC degraders were designed to mimic the function of autophagy receptors, simultaneously binding with the cellular targets and the LC3 proteins on the autophagosomal membrane, eventually transporting the target to the autophagy-lysosomal process for degradation. The AceTAC degradation system provides design principles for antibody-based degradation through autophagy, largely expanding the scope of intracellular targeted degradation technologies.


Assuntos
Autofagia , Agregados Proteicos , Animais , Retículo Endoplasmático/metabolismo , Lisossomos , Peroxissomos/metabolismo , Mamíferos
2.
J Med Virol ; 95(11): e29246, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38010833

RESUMO

The effect of anemia on the post-acute outcome of patients with severe acute respiratory syndrome coronavirus 2 infection was unclear. This study aimed to investigate the potential association between nutritional deficiency anemia (NDA) status and post-acute sequelae of patients with SARS-CoV-2 infection. This retrospective cohort study included patients with coronavirus disease (COVID-19) from January 1, 2022 to November 30, 2022 using the TriNetX research network. The patients were grouped into the NDA group comprising patients diagnosed with NDA and the control group comprising patients without NDA, and propensity score matching (PSM) was performed to balance the two groups. The primary outcome was a composite of post-COVID-19 condition, all-cause hospitalization, and all-cause death. The secondary outcomes were any individual outcomes of the primary composite. The follow-up period was set at 90-180 days after COVID-19 diagnosis. Two cohorts comprising 15 446 nonhospitalized patients with COVID-19 in each group with balanced baseline characteristics were created using PSM. During the follow-up period, the NDA group demonstrated a higher risk of the composite primary outcome, including post-COVID-19 condition, all-cause hospitalization, or all-cause death (hazard ratio [HR], 1.896; 95% confidence interval [CI] = 1.757-2.045). Regarding secondary outcomes, the NDA group was associated with worse outcomes, including post-COVID-19 condition (HR, 1.992; 95% CI = 1.403-2.828), all-cause hospitalization (HR, 1.856; 95% CI = 1.714-2.009), and all-cause death (HR, 3.922; 95% CI = 2.910-5.285) compared to the control group. Among nonhospitalized patients with COVID-19, NDA was associated with a higher risk of post-COVID-19 condition, all-cause hospitalization, and all-cause death during the 90-180-day follow-up period.


Assuntos
Anemia , COVID-19 , Desnutrição , Humanos , Estudos Retrospectivos , COVID-19/complicações , Teste para COVID-19 , SARS-CoV-2 , Anemia/epidemiologia , Anemia/etiologia , Progressão da Doença
3.
BMC Cancer ; 23(1): 599, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380971

RESUMO

BACKGROUND: Dihydropyrimidinase-like 3 (DPYSL3) is a cytosolic phosphoprotein expressed in the nervous system and is crucial for neurogenesis. A previous study showed that increased DPYSL3 expression promotes tumour aggressiveness in pancreatic ductal adenocarcinoma, gastric cancer, and colon cancer. However, the role of DPYSL3 in affecting the biological behaviour of urothelial carcinoma (UC) is not yet understood. METHODS: A UC transcriptomic dataset from the Gene Expression Omnibus and the Urothelial Bladder Cancer (BLCA) dataset from The Cancer Genome Atlas were used for the in silico study. We collected 340 upper urinary tract urothelial carcinoma (UTUC) and 295 urinary bladder urothelial carcinoma (UBUC) samples for the immunohistochemical study. Fresh tumour tissue from 50 patients was used to examine the DPYSL3 mRNA level. In addition, urothelial cell lines with and without DPYSL3 knockdown were used for the functional study. RESULTS: The in silico study revealed that DPYSL3 correlated with advanced tumour stage and metastasis development while functioning primarily in the nucleobase-containing compound metabolic process (GO:0006139). DPYSL3 mRNA expression is significantly upregulated in advanced UC. Furthermore, overexpression of the DPYSL3 protein is significantly associated with the aggressive behaviour of UTUC and UBUC. DPYSL3 expression independently predicts disease-specific survival (DSS) and metastatic-free survival (MFS) in patients with UC. In non-muscle-invasive UBUC, DPYSL3 expression predicts local recurrence-free survival. UC cell lines with DPYSL3 knockdown exhibited decreased proliferation, migration, invasion, and human umbilical vein endothelial cells (HUVECs) tube formation but increased apoptosis and G1 arrest. Gene ontology enrichment analysis revealed that the enriched processes related to DPYSL3 overexpression in UC were tissue morphogenesis, cell mesenchyme migration, smooth muscle regulation, metabolic processes, and RNA processing. In vivo study revealed DPYSL3 knockdown in UC tumours significantly suppressed the growth of tumours and decreased MYC and GLUT1 protein expression. CONCLUSIONS: DPYSL3 promotes the aggressiveness of UC cells by changing their biological behaviours and is likely associated with cytoskeletal and metabolic process modifications. Furthermore, DPYSL3 protein overexpression in UC was associated with aggressive clinicopathological characteristics and independently predicted poor clinical outcomes. Therefore, DPYSL3 can be used as a novel therapeutic target for UC.


Assuntos
Carcinoma de Células de Transição , Neoplasias Pancreáticas , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Regulação para Cima , Células Endoteliais , Prognóstico , Proteínas Musculares/genética
4.
World J Surg Oncol ; 21(1): 62, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36841776

RESUMO

BACKGROUND: With the advance in genome-wide analyses, genetic alternations have been found to play an important role in carcinogenesis and aggressiveness of UC. Through bioinformatic analysis of gene expression profiles of urinary bladder urothelial carcinoma (UBUC) from publicly available GEO dataset (GSE31684), Zinc finger and SCAN domain containing 4 (ZSCAN4) was identified as a significant downregulated gene in muscle-invasive bladder cancer when compared with non-muscle-invasive bladder cancer. METHODS: The expression of ZSCAN4 was evaluated by immunohistochemistry in 340 upper urinary tract urothelial carcinomas (UTUCs) and 295 UBUCs. The expression profiles of ZSCAN4 and potential signaling pathways were analyzed bioinformatically. RESULTS: In UTUC, low expression of ZSCAN4 was significantly associated with advanced primary pT stage (P = 0.011), increased nodal metastasis (P = 0.002) and increased vascular invasion (P = 0.019). In UBUC, low expression of ZSCAN4 was significantly correlated with advanced primary pT stage (P < 0.001), increased nodal metastasis (P = 0.001), high histological grade (P = 0.003) and increased vascular invasion (P = 0.003). In survival analysis, low expression of ZSCAN4 acted as an independent negative prognostic factor for disease-specific survival and metastasis-free survival both in UTUC and UBUC. Gene ontology analysis showed that ZSCAN4 mRNA and its co-downregulated genes are associated with the mitotic cell cycle. CONCLUSIONS: Low expression of ZSCAN4 predicted worse outcome in urothelial carcinoma and might have potential regulatory role in cell mitosis.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/patologia , Carcinoma de Células de Transição/patologia , Bexiga Urinária/patologia , Estudo de Associação Genômica Ampla , Prognóstico , Pelve Renal/patologia , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética
5.
Acta Cardiol Sin ; 39(3): 457-468, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37229340

RESUMO

Background/Objectives: We aimed to assess the incidence of recurrent cardiovascular (CV) events after the first myocardial infarction (MI), ischemic stroke (IS), or intracerebral hemorrhage (ICH) and to estimate acute and follow-up medical costs. Methods: Using Taiwan's National Health Insurance Research Database, we identified patients with their first MI, IS, or ICH between 2011 and 2017. The cumulative incidence rates of second CV events (including events of the same type [recurrent] or of the other two types) were estimated. The costs for hospitalization and all-cause follow-up were calculated for the first and recurrent CV events and are presented as median (Q1~Q3) in 2017 US dollars. Results: We identified 70,428 patients with a first MI, 123,857 with a first IS, and 41,347 with a first ICH. The cumulative incidence rates of recurrence during the first year and after six years were 3.9% and 10.1% for MI, 5.3% and 13.8% for IS, and 3.9% and 8.9% for ICH, respectively. For first and recurrent nonfatal events, acute hospitalization costs were $4,729 (3,737~5,985) and $4,459 (2,887~6,026) for MI; $1,136 (756~2,183) and $1,224 (774~2,412) for IS; and $2,985 (1,264~8,831) and $2,170 (1,183~4,675) for ICH, respectively. Total annual costs for nonfatal first events in the first year and second year of follow-up were $2413 (1,393~6,120) and $1,293 (654~2,868) for MI, $2,174 (1,040~5,472) and $1,394 (602~3,265) for IS, and $2,963 (995~8,352) and $1,185 (405~3,937) for ICH, respectively. Conclusions: In patients with a first MI, IS, and ICH, recurrent CV events continue to substantially impact public health and escalate the economic burden.

6.
J Am Chem Soc ; 144(29): 13218-13225, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35819848

RESUMO

Protein-protein interactions (PPIs) form complex networks to drive cellular signaling and cellular functions. Precise modulation of a target PPI helps explain the role of the PPI in cellular events and possesses therapeutic potential. For example, valosin-containing protein (VCP/p97) is a hub protein that interacts with more than 30 adaptor proteins involved in various cellular functions. However, the role of each p97 PPI during the relevant cellular event is underexplored. The development of small-molecule PPI modulators remains challenging due to a lack of grooves and pockets in the relatively large PPI interface and the fact that a common binding groove in p97 binds to multiple adaptors. Here, we report an antibody fragment-based modulator for the PPI between p97 and its adaptor protein NSFL1C (p47). We engineered these antibody modulators by phage display against the p97-interacting domain of p47 and minimizing binding to other p97 adaptors. The selected antibody fragment modulators specifically disrupt the intracellular p97/p47 interaction. The potential of this antibody platform to develop PPI inhibitors in therapeutic applications was demonstrated through the inhibition of Golgi reassembly, which requires the p97/p47 interaction. This study presents a unique approach to modulate specific intracellular PPIs using engineered antibody fragments, demonstrating a method to dissect the function of a PPI within a convoluted PPI network.


Assuntos
Adenosina Trifosfatases , Proteínas de Ciclo Celular , Proteínas Adaptadoras de Transdução de Sinal/química , Adenosina Trifosfatases/metabolismo , Proteínas de Ciclo Celular/química , Fragmentos de Imunoglobulinas , Ligação Proteica , Proteína com Valosina/metabolismo
7.
Oncology ; 100(9): 475-484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35772391

RESUMO

Introduction: Nasopharyngeal carcinoma (NPC) is the most common malignant tumor in southern China and Southeast Asia. Although substantial research on NPC has been conducted, the resulting improvement in clinical outcomes remains very disappointing. NPC treatment typically involves radiation therapy and chemotherapy, but the high incidence of metastasis and recurrence in NPC patients result in poor survival. Therefore, identifying potential biomarkers and discovering therapeutic targets are necessary to design tailored treatments based on the genetic profiles of NPC patients. Methods: Correlations of protein immunostaining with clinicopathological features were analyzed by Pearson's χ2 test. The Kaplan-Meier method with a log-rank test was used to generate survival curves. Multivariate analysis was performed using the Cox proportional hazards model. Results: In this study, we comparatively analyzed cytoskeletal organization and biogenesis (GO:0007010) and tumorigenesis in the NPC transcriptome (GSE12452) and found that formin-like 2 (FMNL2) expression was significantly upregulated in NPC tumor tissues. Moreover, high FMNL2 expression was significantly correlated with primary tumor stage (p = 0.001), lymph node status (p = 0.004), cancer stage (p = 0.006), and histological grade (p = 0.040). More importantly, high FMNL2 expression was significantly correlated with poor survival in NPC patients according to univariate analysis and multivariate analysis. Conclusion: This study reveals that FMNL2 may be an important potential biomarker for evaluating the prognosis of NPC patients.


Assuntos
Carcinoma , Forminas , Neoplasias Nasofaríngeas , Biomarcadores Tumorais/genética , Carcinoma/genética , Forminas/genética , Humanos , Estimativa de Kaplan-Meier , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Prognóstico
8.
Oncology ; 100(9): 485-497, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35817020

RESUMO

Introduction: Dysregulation of metal ion homeostasis is associated with urothelial carcinogenesis. From a published urinary bladder urothelial carcinoma (UBUC) transcriptome, we identified metallothionein 2A (MT2A) as the most significantly upregulated gene implicated in cancer progression among metal ion binding-related genes. Therefore, we analyzed the association between MT2A expression and clinical significance in our well-characterized cohort of patients with upper tract urothelial carcinoma (UTUC) and UBUC. Methods: We retrospectively reviewed the clinicopathological characteristics of 295 and 340 patients with UBUC and UTUC, respectively. MT2A expression was assessed using real-time reverse transcriptase-polymerase chain reaction and immunohistochemistry. We further correlated MT2A expression with clinicopathological factors, disease-specific survival (DSS) and metastasis-free survival (MFS) using the Pearson's χ2 test, Kaplan-Meier analysis, and multivariate Cox proportional hazards model. Results: High MT2A expression was significantly associated with aggressive pathological features including high tumor stage, lymph node metastasis, high tumor grade, vascular invasion, and perineural invasion. In the Kaplan-Meier analysis, high MT2A expression was significantly correlated with poor DSS (p < 0.0001) and MFS (p < 0.0001); in the multivariate analysis, it was an independent predictor of CSS (p < 0.001) and MFS (p = 0.001). Gene coexpression analysis demonstrated that MT2A overexpression promotes UC progression through complement activation. Conclusion: High MT2A expression correlated with aggressive UC features and was an independent predictor of cancer metastasis and patient survival, suggesting its role in risk stratification and decision-making in patients with UTUC and UBUC.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Neoplasias Urológicas , Carcinoma de Células de Transição/patologia , Humanos , Metalotioneína/genética , Prognóstico , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
9.
Int J Mol Sci ; 23(7)2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35409350

RESUMO

Both in Taiwan and around the world, lung cancer is a primary cause of cancer-related deaths. In Taiwan, the most prevalent form of lung cancer is lung adenocarcinoma, a type of non-small-cell lung carcinoma. Although numerous lung cancer therapies are available, their clinical outcomes are unsatisfactory. Natural products, including fungal metabolites, are excellent sources of pharmaceutical compounds used in cancer treatment. We employed in vitro cell invasion, cell proliferation, cell migration, cell viability, and colony formation assays with the aim of evaluating the effects of coriloxin, isolated from fermented broths of Nectria balsamea YMJ94052402, on human lung adenocarcinoma CL1-5 and/or A549 cells. The potential targets regulated by coriloxin were examined through Western blot analysis. The cytotoxic effect of coriloxin was more efficiently exerted on lung adenocarcinoma cells than on bronchial epithelial cells. Moreover, low-concentration coriloxin significantly suppressed adenocarcinoma cells' proliferative, migratory, and clonogenic abilities. These inhibitory effects were achieved through ERK/AKT inactivation, epithelial-mesenchymal transition regulation, and HLJ1 expression. Our findings suggest that coriloxin can be used as a multitarget anticancer agent. Further investigations of the application of coriloxin as an adjuvant therapy in lung cancer treatment are warranted.


Assuntos
Adenocarcinoma de Pulmão , Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Células A549 , Adenocarcinoma de Pulmão/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/metabolismo
10.
Acta Cardiol Sin ; 38(1): 39-46, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35068882

RESUMO

BACKGROUND: Despite the increasing prevalence of therapies utilizing immune checkpoint inhibitors (ICIs), the associated cardiovascular complications have been poorly reported. Given the fatality of ICI-related complications, especially myocarditis, optimal risk stratification to predict major adverse cardio- and cerebrovascular events (MACCEs) in patients receiving ICIs is mandatory. METHODS: We collected clinical data from patients receiving ICIs, and the primary outcomes were MACCEs, including myocarditis, heart failure, and ischemic stroke. Other systemic immune responses relating to ICIs were also recorded. The median follow-up duration was 3 years. RESULTS: Among 580 patients, the incidence of MACCEs was 3.9%. Older patients, male patients, and patients with lung cancer, liver cirrhosis, or diabetes had higher risks of MACCEs. There was no significant difference between the use of PD-1/PD-L1 inhibitors or CTLA inhibitors in terms of developing cardiovascular toxicities. The development of ICI-related MACCEs was associated with worse survival. Notably, after re-review by specialists, three patients eventually diagnosed with ICI-related myocarditis had not previously been identified. Only one was treated with pulse steroids, and none survived. The most common concomitant extracardiac immune-related adverse events were myositis/dermatitis, endocrine toxicity and hepatitis. CONCLUSIONS: Collectively, ICIs may lead to severe cardiovascular toxicities and require more attention. Early identification, proper diagnosis, and prompt treatment are pivotal for improving survival.

11.
Molecules ; 26(19)2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34641562

RESUMO

Oral cancers, hepatocellular carcinoma, and colorectal cancers are the three most common cancers, leading to 18,000 cases of cancer-related mortality in Taiwan per year. To bridge the gap towards clinical translation, we developed a circulating tumor cell (CTC) organoid culture workflow that efficiently expands CTC from patients to test Antrodia Cinnamomea mycelium-derived bioactive compounds. Three ACM-derived bioactive compounds were evaluated for tumor chemosensitization characteristics. Significant and consistent cytotoxic/5-FU sensitizing effects of GKB202 were found on 8 different patient-derived tumors. Acute toxicity profile and hepatic metabolism of GKB202 in rats suggest GKB202 is rapidly cleared by liver and is well tolerated up to the dose of 20 mg/kg. This comprehensive study provides new evidence that liquid fermentation of Antrodia cinnamomea mycelium (ACM) contains bioactive compounds that lead to effective control of CTC, especially when combined with 5-FU. Together, these data suggest ACM-derived GKB202 may be considered for further clinical investigation in the context of 5-FU-based combination therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/uso terapêutico , Polyporales/química , Adulto , Idoso , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micélio/química , Organoides , Ratos , Células Tumorais Cultivadas
12.
Justice Q ; 38(2): 344-374, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025017

RESUMO

Research on communities and crime has predominantly focused on social conditions within an area or in its immediate proximity. However, a growing body of research shows that people often travel to areas away from home, contributing to connections between places. A few studies highlight the criminological implications of such connections, focusing on important but rare ties like co-offending or gang conflicts. The current study extends this idea by analyzing more common ties based on commuting across Chicago communities. It integrates standard criminological methods with machine learning and computational statistics approaches to investigate the extent to which neighborhood crime depends on the disadvantage of areas connected to it through commuting. The findings suggest that connected communities can influence each other from a distance and that connectivity to less disadvantaged work hubs may decrease local crime-with implications for advancing knowledge on the relational ecology of crime, social isolation, and ecological networks.

13.
J Am Chem Soc ; 142(4): 1801-1810, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31881155

RESUMO

Heteroaromatic sulfones react with cysteine via nucleophilic aromatic substitution, providing a mechanistically selective and irreversible scaffold for cysteine conjugation. Here we evaluate a library of heteroaromatic sulfides with different oxidation states, heteroatom substitutions, and a series of electron-donating and electron-withdrawing substituents. Select substitutions profoundly influence reactivity and stability compared to conventional cysteine conjugation reagents, increasing the reaction rate by >3 orders of magnitude. The findings establish a series of synthetically accessible electrophilic scaffolds tunable across multiple centers. New electrophiles and their corresponding alkyne conjugates were profiled directly in cultured cells, achieving thiol saturation in a few minutes at submillimolar concentrations. Direct addition of desthiobiotin-functionalized probes to cultured cells simplified enrichment and elution to enable the mass spectrometry discovery of >3000 reactive and/or accessible thiols labeled in their native cellular environments in a fraction of the standard analysis time. Surprisingly, only half of the annotated cysteines were identified by both iodoacetamide-desthiobiotin and methylsulfonylbenzothiazole-desthiobiotin in replicate experiments, demonstrating complementary detection by mass spectrometry analysis. These probes offer advantages over existing cysteine alkylation reagents, including accelerated reaction rates, improved stability, and robust ionization for mass spectrometry applications. Overall, heteroaromatic sulfones provide modular tunability, shifted chromatographic elution times, and superior in-cell cysteine profiling for in-depth proteome-wide analysis and covalent ligand discovery.


Assuntos
Cisteína/química , Sulfonas/química , Alcinos/química , Indicadores e Reagentes/química , Sondas Moleculares/química , Oxirredução , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Chembiochem ; 18(20): 2028-2032, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-28809078

RESUMO

Cysteine residues are susceptible to oxidation to form S-sulfinyl (R-SO2 H) and S-sulfonyl (R-SO3 H) post-translational modifications. Here we present a simple bioconjugation strategy to label S-sulfinated proteins by using reporter-linked maleimides. After alkylation of free thiols with iodoacetamide, S-sulfinated cysteines react with maleimide to form a sulfone Michael adduct that remains stable under acidic conditions. Using this sequential alkylation strategy, we demonstrate differential S-sulfination across mouse tissue homogenates, as well as enhanced S-sulfination following pharmacological induction of endoplasmic reticulum stress, lipopolysaccharide stimulation, and inhibitors of the electron transport chain. Overall, this study reveals a broadened profile of maleimide reactivity across cysteine modifications, and outlines a simple method for profiling the physiological role of cysteine S-sulfination in disease.


Assuntos
Maleimidas/química , Sondas Moleculares/química , Proteínas/química , Proteínas/metabolismo , Ácidos Sulfínicos/metabolismo , Enxofre/metabolismo , Células HEK293 , Humanos , Modelos Moleculares , Conformação Proteica
16.
Res Sports Med ; 25(4): 470-479, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28816504

RESUMO

This study's aim was to investigate the test-retest reliability of the 3-min all-out running test (3MRT) in hot environments. Twelve male sprinters (age 21.2 ± 1.8 years; height 1.78 ± 0.01 m; weight 71.0 ± 1.6 kg; [Formula: see text] 55.0 ± 1.0 mL kg-1 min-1) performed an incremental exercise test in a laboratory, during which the first and second ventilatory thresholds (VT1 and VT2) and [Formula: see text] were determined. In addition, they performed two 3MRTs on an outdoor track in a hot environment, during which the critical velocity (CV) and anaerobic capacity (D') were estimated. Significant reproducibility was found in CV and D' (ICC = 0.74 and 0.61, P < 0.05). The average CV in 3MRTs (3.09 ± 0.13 m s-1) correlated significantly with VT1 (3.13 ± 0.07 m s-1, P < 0.05). The 3MRT is a reliable tool for measuring CV and D', while CV from 3MRT in a hot environment was identical to VT1.


Assuntos
Teste de Esforço/normas , Temperatura Alta , Corrida/fisiologia , Humanos , Masculino , Consumo de Oxigênio , Reprodutibilidade dos Testes , Adulto Jovem
17.
Eur J Appl Physiol ; 116(9): 1693-702, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27372742

RESUMO

PURPOSE: To investigate the effect of caffeine ingestion on the 3-min all-out test (3MT) performance and plasma electrolytes in athletes. METHODS: Fifteen collegiate male basketball players were recruited and completed two trials separated by at least 1 week in caffeine (CAF, 6 mg kg(-1)) and placebo conditions. During the first visit, participants performed an incremental cycling test to determine their 3MT resistance. After a familiarization trial, participants performed a CAF or PL trial according to a randomized crossover design. One hour after ingesting capsules, the participants performed the 3MT to estimate the end-test power (EP) and work done above EP (WEP). Blood samples for sodium (Na(+)), potassium (K(+)), pH, and lactate concentrations were drawn pretest, 1 h after ingestion, and posttest. RESULTS: Significant differences in WEP (CAF vs. PL, 13.4 ± 3.0 vs. 12.1 ± 2.7 kJ, P < 0.05) but not in EP (CAF vs. PL, 242 ± 37 vs. 244 ± 42 W, P > 0.05) were determined between the conditions. Compared with the PL condition, the CAF condition yielded significantly higher power outputs (60-150 s), a lower fatigue rate during the 3MT (CAF vs. PL, 0.024 ± 0.007 vs. 0.029 ± 0.006 s(-1), P < 0.05), a significantly higher lactate concentration after the 3MT, and significantly lower K(+) concentrations at 1 h after caffeine ingestion. There were no significant interaction effects for pH and Na(+) concentrations. CONCLUSIONS: Caffeine ingestion did not change EP but improved WEP and the rate of decline in power output during short-term, severe exercise.


Assuntos
Cafeína/administração & dosagem , Suplementos Nutricionais , Transferência de Energia/fisiologia , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Administração Oral , Relação Dose-Resposta a Droga , Método Duplo-Cego , Transferência de Energia/efeitos dos fármacos , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Adulto Jovem
18.
Acta Cardiol Sin ; 32(5): 550-559, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27713603

RESUMO

BACKGROUND: As cancer therapies have improved, patient life spans have been extended but quality of life has been threatened by chemotherapy induced cardiotoxicity. Most cardiac complications remain unobserved until specific symptoms develop. Speckle-tracking echocardiography is a sensitive imaging modality in detecting early occult myocardial dysfunction. METHODS: A total number of 35 patients newly diagnosed with breast cancer and preparing for epirubicin therapy were prospectively recruited. Echocardiography, including speckle-tracking echocardiography, was performed sequentially at baseline (T1), after the first cycle (T2) and after the third cycle (T3) of epirubicin. At each visit, the severity of dyspnea was evaluated by the assessment scale. RESULTS: Compared with the baseline, right ventricular longitudinal strain (RVLS_FW) at T2 significantly declined (-22.49 ± 4.97 vs. -18.48 ± 4.46, p = 0.001), which was also positively associated with the development of dyspnea (R2 = 0.8, p = 0.01). At T3, both the left ventricular global longitudinal strain and RVLS_FW were significantly impaired (-21.4 ± 4.12 vs. -16.94 ± 6.81%; -22.49 ± 4.97 vs. -16.86 ± 7.27%, p = 0.01; 0.001, respectively). Also, the accumulating dose of epirubicin positively correlated with the development of dyspnea (R2 = 0.38, p = 0.04) and the decline of RVLS_FW (R2 = 0.53, p = 0.02). Notably, compared with the other echocardiographic parameters only RVLS_FW at the early stage (T2) significantly correlated with the development of dyspnea (odds ratio: 1.84, 95% confidence interval: 1.22-2.78, p = 0.04). CONCLUSIONS: RVLS_FW sensitively predicts dyspnea development in breast cancer patients receiving epirubicin therapy. However, larger scale studies are required to validate its role in long-term patient survival.

19.
Mol Divers ; 18(1): 13-23, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24222528

RESUMO

N-Acetylglucosamine-bearing triterpenoid saponins (GNTS) were reported to be a unique type of saponins with potent anti-tumor activity. In order to study the structure-activity relationship of GNTS, 24 oleanolic acid saponins with (1 --> 3)-linked, (1 --> 4)-linked, (1 --> 6)-linked N-acetylglucosamine oligosaccharide residues were synthesized in a combinatorial and concise method. The cytotoxicity of these compounds toward the leukemia cell line HL-60 and the colorectal cancer cell line HT-29 could not be improved. Half maximal inhibition below 10 µM was achieved in one single case. The study revealed that the activity decreased following the order of 3' > 4' > 6' glycosyl modifications. GNTS that incorporated (D/L)-xylose and L-arabinose at positions 3' and 4' were more potent than those bearing other sugars.


Assuntos
Acetilglucosamina/química , Acetilglucosamina/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Ácido Oleanólico/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Acetilglucosamina/síntese química , Antineoplásicos/síntese química , Técnicas de Química Sintética , Técnicas de Química Combinatória , Glicosilação , Células HL-60 , Células HT29 , Humanos , Bibliotecas de Moléculas Pequenas/síntese química , Relação Estrutura-Atividade
20.
Eur J Appl Physiol ; 114(7): 1533-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24748531

RESUMO

PURPOSE: To determine the effects of co-ingesting caffeine (CAF) and carbohydrate (CHO) on high-intensity intermittent sprints (HIS) performance and physiological responses. METHODS: Twelve active males underwent 4 interventions at least 7 days apart in a randomized, double-blind, placebo-controlled, balanced trial. A meal contained 65 % CHO was provided 2 h before the HIS test. Participants ingested the placebo (PLA) or CAF (6 mg kg(-1) BW) 1 h before taking an HIS test, and ingested a PLA or CHO solution (0.8 g kg(-1) BW) before undergoing the testing protocol. The HIS protocol comprised ten sets of 5 × 4-s sprints on a cycle ergometer with a 2-min recovery between each set. RESULTS: There was no significant difference between peak power output and mean power output between trials (p > 0.05). Compared with PLA, CAF + CHO resulted in a 5.2 % reduction in total work, corresponding to a 24.7-25.7 % increase in fatigue at the end stage of the HIS. The administration of CAF + CHO supplementation also resulted in an 11.1 % increase in blood lactate, and elevated blood glucose concentrations throughout HIS testing compared with PLA (p < 0.05). Cortisol concentrations also increased with CAF + CHO intake compared with PLA; however, there was no significant effect of CAF + CHO supplementation on testosterone concentrations. CONCLUSION: Co-ingestion of CAF and CHO did not improve high-intensity sprint cycling performance or reduce fatigue in active males. Moreover, combined CAF and CHO supplementation might facilitate catabolism during prolonged high-intensity intermittent exercise.


Assuntos
Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Ciclismo , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Método Duplo-Cego , Teste de Esforço , Humanos , Hidrocortisona/sangue , Ácido Láctico/sangue , Masculino , Contração Muscular/efeitos dos fármacos , Fadiga Muscular , Músculo Esquelético/metabolismo , Recuperação de Função Fisiológica , Taiwan , Testosterona/sangue , Fatores de Tempo , Adulto Jovem
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