Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Formos Med Assoc ; 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38246800

RESUMO

BACKGROUND/PURPOSE: Zirconia has been a popular material in dental implantology with good biocompatibility. But few research focused on its application in implant drills. This study aimed to investigate the physical, thermal, and biological effects on using the zirconia and stainless-steel drills for implant bone site preparation. METHODS: We performed a series of experiments to evaluate the physical wearing properties of zirconia and stainless-steel drills of identical diameter and similar shape. During the implant site preparation thermal test, we subjected both drills onto a resin-embedded bone, utilizing a thermal couple device without irrigation. Moreover, we conducted a cell study by collecting bone cells in vivo while preparing the implant site with both tested drills. The cell activity was evaluated through cell proliferation colorimetric analysis (XTT) and alkaline phosphatase (ALP) activity measurements. RESULTS: The zirconia drill outperforms the stainless-steel drill in terms of requiring less force, maintaining stability over repeated cutting tests, and generating lower temperatures during drilling (stainless-steel drill: 45.48 ± 1.31 °C; zirconia-coated drill: 32.98 ± 1.21 °C, P = 0.000247). Meanwhile, both types of drills show similar results in XTT colorimetric analysis and ALP activity test. CONCLUSION: The thermal effect study is more favorable for using the zirconia drill than the stainless-steel drill for bone preparation. Cytological analysis indicate that the zirconia drill produces a similar impact on bone cells activity as the stainless-steel drill. Therefore, we conclude that the zirconia drills offer a good cutting effect similar to currently available stainless-steel drills in various aspects.

2.
Int J Mol Sci ; 23(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36142591

RESUMO

Combined inhibition of vascular endothelial growth factor receptor (VEGFR) and the programmed cell death protein 1 (PD-1) pathways has shown efficacy in multiple cancers; however, the clinical outcomes show limited benefits and the unmet clinical needs still remain and require improvement in efficacy. Using murine colon carcinoma (CT26) allograft models, we examined the efficacy and elucidated novel tumor microenvironment (TME) remodeling mechanisms underlying the combination of chidamide (a benzamide-based class l histone deacetylase inhibitor; brand name in Taiwan, Kepida®) with VEGF receptor tyrosine kinase inhibitor (TKIs; cabozantinib/regorafenib, etc.) and immune checkpoint inhibitors (ICIs; anti-PD-1/anti-PD-L1/anti-CTLA-4 antibodies). The TME was assessed using flow cytometry and RNA-sequencing to determine the novel mechanisms and their correlation with therapeutic effects in mice with significant treatment response. Compared with ICI alone or cabozantinib/regorafenib + ICI, combination of chidamide + cabozantinib/regorafenib + ICI increased the tumor response and survival benefits. In particular, treatment of CT26-bearing mice with chidamide + regorafenib + anti-PD-1 antibody showed a better objective response rate (ORR) and overall survival (OS). Similar results were observed in anti-PD-1 treatment-resistant mice. After treatment with this optimal combination, in the TME, RNA-sequencing revealed that downregulated mRNAs were correlated with leukocyte migration, cell chemotaxis, and macrophage gene sets, and flow cytometry analysis showed that the cell numbers of myeloid-derived polymorphonuclear suppressor cells and tumor-associated macrophages were decreased. Accordingly, chidamide + regorafenib + anti-PD-1 antibody combination therapy could trigger a novel TME remodeling mechanism by attenuating immunosuppressive cells, and restoring T-cell activation to enhance ORR and OS. Our studies also showed that the addition of Chidamide to the regorafenib + anti-PD-1 Ab combination could induce a durable tumor-specific response by attenuating immune suppression in the TME. In addition, this result suggests that TME remodeling, mediated by epigenetic immunomodulator combined with TKI and ICI, would be more advantageous for achieving a high objective response rate, when compared to TKI plus ICI or ICI alone, and maintaining long-lasting antitumor activity.


Assuntos
Neoplasias do Colo , Microambiente Tumoral , Aminopiridinas , Anilidas , Animais , Benzamidas/farmacologia , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Camundongos , Compostos de Fenilureia , Receptor de Morte Celular Programada 1 , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas , RNA , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Fator A de Crescimento do Endotélio Vascular
3.
Sci Rep ; 12(1): 1100, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35058524

RESUMO

Immune checkpoint inhibitors (ICIs) have shown clinical benefit in solid tumors, with modest rates of clinical response. Hence, improved therapeutic approaches need to be investigated. Herein, we assessed a combination of chidamide plus celecoxib (called CC-01) combined with programmed cell death protein 1 (PD-1) blockade in a CT26 model as potent tumor microenvironment (TME) regulator. The antitumor activity was assessed by measuring tumor size, overall response rate, and survival rate. Immune profiling of tumor-infiltrating lymphocytes was performed by flow cytometry. Tumor tissues were assessed by chip assay to predict the possible pathway. Tumor size was significantly reduced in mice treated with CC-01 combined with or without anti-PD-1 antibody, however the triple combination therapy consistently demonstrated that it significantly increased both the ORR and survival rate in term of clinical applications. In the combination group, immune landscape profiling revealed decreased populations of immunosuppressive regulatory T cells, myeloid-derived suppressor cells, and tumor-associated macrophages. Analysis of the mouse tumor chip data using Gene Ontology enrichment analysis of biological processes revealed that the triple combination upregulated genes associated with responses to interferon-gamma. Our results demonstrated that CC-01 possessed potent TME regulatory properties, augmenting the antitumor effect when combined with ICIs. This antitumor effect was achieved by altering the immune landscape in TILs (tumor-infiltrating lymphocytes) and was associated with immune cell activation in the TME. Furthermore, CC-01 demonstrated potent anticancer immune response activity, mainly reducing the number and function of several immunosuppressive cells. The combination of CC-01 with an ICI will further enhance the anticancer effect and boost the immune response rate. Collectively, our results support the clinical evaluation of CC-01 in combination with ICIs in several advanced cancers.


Assuntos
Adenocarcinoma/tratamento farmacológico , Aminopiridinas/farmacologia , Benzamidas/farmacologia , Celecoxib/farmacologia , Microambiente Tumoral/imunologia , Adenocarcinoma/metabolismo , Aminopiridinas/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Benzamidas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Quimioterapia Combinada/métodos , Inibidores de Checkpoint Imunológico/farmacologia , Interferon gama/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Supressoras Mieloides/imunologia , Invasividade Neoplásica , Processos Neoplásicos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Ecol Evol ; 11(11): 6730-6741, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34141253

RESUMO

Investigating factors that promote group living in animals can help us to understand the evolution of sociality. The dark woolly bat, Kerivoula furva, forms small groups and uses furled leaves of banana (Musa formosana) as day roosts in subtropical Taiwan. In this study, we reported on the roosting ecology and social organization of K. furva. We examined whether ecological constraints, demographic traits, and physiological demands contributed to its sociality. From July 2014 to May 2016, we investigated the daily roost occupation rate, group size, and composition of each roost, and we calculated association indices in pairs. The results showed K. furva lived in groups throughout the year, and the average daily roost occupation rate was approximately 6.7% of all furled leaves that were suitable for roosting. The size of roosting groups of adults in each roost varied between 1 and 13; group size was independent of air temperature during both reproductive and nonreproductive seasons. The vast majority of roosting groups was composed of females and their young, and males frequently roosted solitarily or in a bachelor group. Forty adult bats were captured ≥4 times during the study period. The association indices in pairs of these 40 bats ranged between 0 and 0.83 with an average of 0.05 ± 0.14 (n = 780). The average association index of female-female pairs was significantly higher than that of female-male pairs and male-male pairs. Based on the association indices, the 40 bats were divided into seven social groups with social group sizes that varied between 2 and 10. Despite changing day roosts frequently, the relatively stable social bonds were maintained year-round. Our results that groups of K. furva were formed by active aggregation of multiple generation members supported the demographic traits hypothesis.

5.
Oncogene ; 37(34): 4662-4678, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29755127

RESUMO

Triple-negative breast cancer (TNBC) patients usually lead to poor prognosis and survival because of metastasis. The major sites for TNBC metastasis include the lungs, brain, liver, and bone. Long non-coding RNAs (lncRNAs) are non-protein-coding transcripts longer than 200 nucleotides and have been reported as important regulators in BC metastasis. However, the underlying mechanisms for lncRNAs regulating TNBC metastasis are not fully understood. Here we found that linc-ZNF469-3 was highly expressed in lung-metastatic LM2-4175 TNBC cells and overexpression of linc-ZNF469-3 enhanced invasion ability and stemness properties in vitro and lung metastasis in vivo. Furthermore, we found linc-ZNF469-3 physically interacted with miR-574-5p and overexpression of miR-574-5p attenuated ZEB1 expression. Importantly, endogenous high expressions of linc-ZNF469-3 and ZEB1 were correlated with tumor recurrence in TNBC patients with lung metastasis. Taken together, our findings suggested that linc-ZNF469-3 promotes lung metastasis of TNBC through miR-574-5p-ZEB1 signaling axis and may be used as potential prognostic marker for TNBC patients.


Assuntos
Neoplasias Pulmonares/genética , MicroRNAs/genética , Metástase Neoplásica/genética , RNA Longo não Codificante/genética , Fatores de Transcrição/genética , Neoplasias de Mama Triplo Negativas/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/patologia , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Transdução de Sinais/genética , Neoplasias de Mama Triplo Negativas/patologia
6.
Mol Ecol ; 24(23): 5910-26, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26475683

RESUMO

Cases of geographically restricted co-occurring sister taxa are rare and may point to potential divergence with gene flow. The two bat species Murina gracilis and Murina recondita are both endemic to Taiwan and are putative sister species. To test for nonallopatric divergence and gene flow in these taxa, we generated sequences using Sanger and next-generation sequencing, and combined these with microsatellite data for coalescent-based analyses. MtDNA phylogenies supported the reciprocally monophyletic sister relationship between M. gracilis and M. recondita; however, clustering of microsatellite genotypes revealed several cases of species admixture suggesting possible introgression. Sequencing of microsatellite flanking regions revealed that admixture signatures stemmed from microsatellite allele homoplasy rather than recent introgressive hybridization, and also uncovered an unexpected sister relationship between M. recondita and the continental species Murina eleryi, to the exclusion of M. gracilis. To dissect the basis of these conflicts between ncDNA and mtDNA, we analysed sequences from 10 anonymous ncDNA loci with *beast and isolation-with-migration and found two distinct clades of M. eleryi, one of which was sister to M. recondita. We conclude that Taiwan was colonized by the ancestor of M. gracilis first, followed by the ancestor of M. recondita after a period of allopatric divergence. After colonization, the mitochondrial genome of M. recondita was replaced by that of the resident M. gracilis. This study illustrates how apparent signatures of sympatric divergence can arise from complex histories of allopatric divergence, colonization and hybridization, thus highlighting the need for rigorous analyses to distinguish between such scenarios.


Assuntos
Quirópteros/classificação , Fluxo Gênico , Especiação Genética , Genética Populacional , Animais , Quirópteros/genética , DNA Mitocondrial/genética , Ilhas , Repetições de Microssatélites , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
7.
Zootaxa ; 3920(2): 301-42, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25781252

RESUMO

In taxonomic accounts, three species of Myotis have been traditionally reported to occur on the island of Taiwan: Watase's bat (M. formosus watasei Kishida), the Formosan broad-muzzled bat (M. muricola latirostris Kishida) and the Formosan mouse-eared bat (M. adversus taiwanensis Linde). The discovery in 1997 of an unknown taxon not fitting to the description of any of these species encouraged us to re-examine more thoroughly the systematics and phylogeny of Myotis bats inhabiting Taiwan. We used a combination of morphologic and molecular methods to aid the identification of the different taxa from this island and reconstruct their phylogenetic relationships. Multivariate analyses based on 17 craniodental characters of 105 specimens caught across Taiwan and further external characters allowed us to discriminate eight taxa of Myotinae co-occurring on this island. A subset of 80 specimens were further sequenced for the cytochrome b gene (1140 bp) and subjected to phylogenetic reconstructions including representative species from adjacent China and from all main lineages of the worldwide Myotis radiation. These molecular reconstructions showed that the Myotinae from Taiwan are phylogenetically diverse and are issued from several independent clades. The genetic results were completely congruent with the phenetic groupings based on craniodental and external morphology, as each of the eight Taiwanese taxa proved to be reciprocally monophyletic. Two unnamed taxa that did not fit into any of the known species were described as species new to science. Furthermore the taxon latirostris usually associated to the Asian M. muricola, was phylogenetically and morphologically distant from any other known Myotis and was assigned here to the fossil (Miocene) genus Submyotodon. Submyotodon latirostris, M. secundus sp. n. and M. soror sp. n. are endemic species from Taiwan, whereas the other five Myotis are more widespread and also found in the mainland. An identification key is provided to ease the discrimination of these Myotinae species in Taiwan and adjacent China.


Assuntos
Quirópteros/anatomia & histologia , Quirópteros/classificação , Filogenia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , China , Quirópteros/genética , Quirópteros/crescimento & desenvolvimento , Ecossistema , Feminino , Fósseis/anatomia & histologia , Masculino , Tamanho do Órgão , Taiwan
8.
J Med Syst ; 38(6): 58, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24878780

RESUMO

Chest auscultation is a crucial and efficient method for diagnosing lung disease; however, it is a subjective process that relies on physician experience and the ability to differentiate between various sound patterns. Because the physiological signals composed of heart sounds and pulmonary sounds (PSs) are greater than 120 Hz and the human ear is not sensitive to low frequencies, successfully making diagnostic classifications is difficult. To solve this problem, we constructed various PS recognition systems for classifying six PS classes: vesicular breath sounds, bronchial breath sounds, tracheal breath sounds, crackles, wheezes, and stridor sounds. First, we used a piezoelectric microphone and data acquisition card to acquire PS signals and perform signal preprocessing. A wavelet transform was used for feature extraction, and the PS signals were decomposed into frequency subbands. Using a statistical method, we extracted 17 features that were used as the input vectors of a neural network. We proposed a 2-stage classifier combined with a back-propagation (BP) neural network and learning vector quantization (LVQ) neural network, which improves classification accuracy by using a haploid neural network. The receiver operating characteristic (ROC) curve verifies the high performance level of the neural network. To expand traditional auscultation methods, we constructed various PS diagnostic systems that can correctly classify the six common PSs. The proposed device overcomes the lack of human sensitivity to low-frequency sounds and various PS waves, characteristic values, and a spectral analysis charts are provided to elucidate the design of the human-machine interface.


Assuntos
Auscultação/instrumentação , Cibernética/instrumentação , Pneumopatias/diagnóstico , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador/instrumentação , Algoritmos , Humanos , Curva ROC , Análise de Ondaletas
9.
PLoS One ; 8(5): e62938, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717396

RESUMO

Laryngeally echolocating bats avoid self-deafening (forward masking) by separating pulse and echo either in time using low duty cycle (LDC) echolocation, or in frequency using high duty cycle (HDC) echolocation. HDC echolocators are specialized to detect fluttering targets in cluttered environments. HDC echolocation is found only in the families Rhinolophidae and Hipposideridae in the Old World and in the New World mormoopid, Pteronotus parnellii. Here we report that the hipposiderid Coelops frithii, ostensibly an HDC bat, consistently uses an LDC echolocation strategy whether roosting, flying, or approaching a fluttering target rotating at 50 to 80 Hz. We recorded the echolocation calls of free-flying C. frithii in the field in various situations, including presenting bats with a mechanical fluttering target. The echolocation calls of C. frithii consisted of an initial narrowband component (0.5±0.3 ms, 90.6±2.0 kHz) followed immediately by a frequency modulated (FM) sweep (194 to 113 kHz). This species emitted echolocation calls at duty cycles averaging 7.7±2.8% (n = 87 sequences). Coelops frithii approached fluttering targets more frequently than did LDC bats (C.frithii, approach frequency  = 40.4%, n = 80; Myotis spp., approach frequency  = 0%, n = 13), and at the same frequency as sympatrically feeding HDC species (Hipposideros armiger, approach rate  = 53.3%, n = 15; Rhinolophus monoceros, approach rate  = 56.7%, n = 97). We propose that the LDC echolocation strategy used by C. frithii is derived from HDC ancestors, that this species adjusts the harmonic contents of its echolocation calls, and that it may use both the narrowband component and the FM sweep of echolocations calls to detect fluttering targets.


Assuntos
Quirópteros/fisiologia , Ecolocação , Comportamento Predatório , Animais , Feminino , Voo Animal , Masculino , Som
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...