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1.
BMC Cancer ; 24(1): 195, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347468

RESUMEN

BACKGROUND: Studies have shown that the absolute lymphocyte count (ALC) and the neutrophil-to-lymphocyte ratio (NLR) are related to the outcomes in patients with breast cancer receiving specific chemotherapies. However, the reports have focussed on the initial blood test and there is a lack of evidence or data to support that dynamic changes of ALC or NLR are associated with the patients' survival outcomes. METHODS: We retrospectively reviewed electronic medical records from patients with breast cancer treated with eribulin from 2015 to 2019 at our institution. Blood test data were available prior to starting eribulin (baseline), and at 1, 3 and 6 months after initiating eribulin. We classified the patients into ALC and NLR high and low groups using the following cut-offs: 1000/µl for ALC and 3 for NLR. We defined ALC and NLR trends as increasing or decreasing compared with the initial data. We assessed the associations between the ALC and NLR with progression-free survival and overall survival. RESULTS: There were 136 patients with breast cancer treated with eribulin. Of these patients, 60 had complete blood tests and follow-up data. Neither a high ALC nor a low baseline NLR was associated with the survival outcome. One month after initiating eribulin treatment, a high ALC and a low NLR were significantly associated with longer progression-free survival (p = 0.044 for each). Three months after initiating eribulin, a high ALC was significantly associated with better overall survival (p = 0.006). A high NLR at 3 or 6 months after initiating eribulin was associated with worse overall survival (p = 0.017 and p = 0.001, respectively). The ALC and NLR trends across times were not associated with survivals. CONCLUSION: We showed that 1, 3 and 6 months after initiating eribulin, a high ALC and a low NLR may be related to the patients' survival outcomes. The ALC and NLR trends were not associated with survival. Accordingly, we believe patients who maintain a high ALC and a low NLR may have better clinical outcomes after initiating eribulin.


Asunto(s)
Neoplasias de la Mama , Furanos , Cetonas , Policétidos Poliéteres , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neutrófilos , Estudios Retrospectivos , Linfocitos , Recuento de Linfocitos
3.
ACS Nano ; 17(4): 3797-3808, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36800201

RESUMEN

Mapping of the spatial and temporal motion of particles inside an optical field is critical for understanding and further improvement of the 3D spatio-temporal control over their optical trapping dynamics. However, it is not trivial to capture the 3D motion, and most imaging systems only capture a 2D projection of the 3D motion, in which the information about the axial movement is not directly available. In this work, we resolve the 3D incorporation trajectories of 200 nm fluorescent polystyrene particles in an optical trapping site under different optical experimental conditions using a recently developed widefield multiplane microscope (imaging volume of 50 × 50 × 4 µm3). The particles are gathered at the focus following some preferential 3D channels that show a shallow cone distribution. We demonstrate that the radial and the axial flow speed components depend on the axial distance from the focus, which is directly related to the scattering/gradient optical forces. While particle velocities and trajectories are mainly determined by the trapping laser profile, they cannot be completely explained without considering collective effects resulting from hydrodynamic forces.

4.
Chemotherapy ; 68(1): 23-34, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36108618

RESUMEN

BACKGROUND: This study aimed to examine the effectiveness and safety of eribulin used as an early-line (EL, i.e., first-/second-line) versus late-line (LL, i.e., third-line and beyond) chemotherapy for recurrent advanced or metastatic breast cancer (A/MBC) patients. METHODS: This study conducted a retrospective observation of A/MBC patients initiating eribulin between January 1, 2015, and June 30, 2019, using medical database at a university-affiliated teaching hospital in Taiwan. Patients were assigned into either the EL or LL group based on the timing of respective eribulin treatments and were observed for at least 6 months up to December 2019 for progression-free survival (PFS), time to treatment failure (TTF), overall survival (OS), disease response, and occurrence of adverse events. The Kaplan-Meier and Cox proportional hazard regression survival analyses were performed. RESULTS: Of 127 patients, 23.6% (n = 30) and 76.4% (n = 97) were assigned to the EL and LL groups, respectively, between which no difference in patient characteristics was noted. Median PFS and TTF were 6.5 months and 5.0 months for the EL and 4.2 months and 3.4 months for the LL, respectively. Median OS could not be estimated in the EL group and was 20.5 months in the LL group. Eribulin as an EL treatment was the only factor associated with longer TTF and OS, whereas the number of metastatic sites was additionally associated with PFS in the multivariate analysis. No complete response was reported in either group, but a partial response was obtained in 6.7% in the EL group and 3.1% in the LL group. The common adverse events between two groups were similar, including leukopenia (80.0%), neutropenia (76.7%), and anemia (60.0%). CONCLUSIONS: The eribulin used as an EL of chemotherapy was effective for A/MBC patients with known toxicities in this study, while eribulin as the LL chemotherapy showed consistent results with previous reports.


Asunto(s)
Neoplasias de la Mama , Neutropenia , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Resultado del Tratamiento , Estudios Retrospectivos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Furanos/efectos adversos
5.
Plants (Basel) ; 11(21)2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36365313

RESUMEN

At least two sets of RNA polymerase (RNAP), nucleus (NEP)- and plastid (PEP)-encoded polymerases, recognizing distinct promoters exist in the plastids of land plants. Most plastid genes are regulated by multiple promoters with different strengths in their response to developmental stages and environmental cues. Recently, we applied chloroplast-targeted transcription activator-like effector nuclease (cpTALEN) technology to site-specifically cause double-strand DNA breaks in the rpoB gene of tobacco, which encodes the ß-subunit of PEP. The repair of damaged chloroplast DNA (cpDNA) through microhomology-mediated recombination caused the functional loss of the rpoB operon and resulted in the heterotrophic growth of an albino plant. We conducted a genome-wide analysis of the steady state of gene expression in the leaf tissue of PEP-deficient tobacco by RNA-Seq and compared it with that of wild-type plants. The expression of NEP genes was up-regulated in PEP-deficient tobacco; in particular, the level of RpoT3 transcripts encoding the specifically plastid-targeted NEP was significantly increased. Alongside most housekeeping genes, NEP also plays an important role in the regulation of gene expression involved in photosynthesis. In contrast, alongside the photosynthesis-related genes, PEP also plays an important role in the regulation of gene expression involved in some housekeeping functions. Furthermore, the mitochondrial DNA copy number and the level of most mitochondrial protein-coding transcripts were slightly increased in PEP-deficient tobacco. The disruption of PEP function not only affected plastid gene expression, but also nuclear and mitochondrial gene expression. This study demonstrated the intercompartmental retrograde signaling in the regulation of gene expression.

6.
Nat Commun ; 13(1): 5325, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36088393

RESUMEN

Optical binding has recently gained considerable attention because it enables the light-induced assembly of many-body systems; however, this phenomenon has only been described between directly irradiated particles. Here, we demonstrate that optical binding can occur outside the focal spot of a single tightly focused laser beam. By trapping at an interface, we assemble up to three gold nanoparticles with a linear arrangement which fully-occupies the laser focus. The trapping laser is efficiently scattered by this linear alignment and interacts with particles outside the focus area, generating several discrete arc-shape potential wells with a half-wavelength periodicity. Those external nanoparticles inside the arcs show a correlated motion not only with the linear aligned particles, but also between themselves even both are not directly illuminated. We propose that the particles are optically bound outside the focal spot by the back-scattered light and multi-channel light scattering, forming a dynamic optical binding network.

7.
J Dent Sci ; 17(2): 1050-1052, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35756769
8.
Cancers (Basel) ; 14(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35406559

RESUMEN

Genetic aberrations involving DNA damage repair (DDR) remain underexplored in gastrointestinal stromal tumors (GISTs). We characterized DDR abnormalities using targeted next-generation sequencing and multiplex ligation-dependent probe amplification, and performed immunofluorescence (IF) and immunohistochemistry (IHC) analyses of γH2AX and 53BP1. Consistent with IF-validated nuclear co-localization, γH2AX and 53BP1 showed robust correlations in expression levels, as did both biomarkers between IF and IHC. Without recurrent pathogenic single-nucleotide variants, heterozygous deletions (HetDels) frequently targeted DNA damage-sensing genes, with CHEK2-HetDel being the most prevalent. Despite their chromosomal proximity, BRCA2 and RB1 were occasionally hit by HetDels and were seldom co-deleted. HetDels of CHEK2 and BRCA2 showed a preference for older age groups, while RB1-HetDel predominated in the non-gastric, high-risk, and 53BP1-overexpressing GISTs. Higher risk levels were consistently related to γ-H2AX or 53BP1 overexpression (all p < 0.01) in two validation cohorts, while only 53BP1 overexpression was associated with the deletion of KIT exon 11 (KITex11-del) among genotyped GISTs. Low expressers of dual biomarkers were shown by univariate analysis to have longer disease-free survival (p = 0.031). However, higher risk levels, epithelioid histology, and KITex11-del retained prognostic independence. Conclusively, IHC is a useful surrogate of laborious IF in the combined assessment of 53BP1 and γ-H2AX to identify potential DDR-defective GISTs, which were frequently aberrated by HetDels and a harbinger of progression.

9.
Plant Sci ; 313: 111028, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34763881

RESUMEN

Transcription activator-like effector nuclease (TALEN) technology has been widely used to edit nuclear genomes in plants but rarely for editing organellar genomes. In addition, ciprofloxacin, commonly used to cause the double-strand break of organellar DNA for studying the repair mechanism in plants, confers no organellar selectivity and site-specificity. To demonstrate the feasibility of TALEN-mediated chloroplast DNA editing and to use it for studying the repair mechanism in plastids, we developed a TALEN-mediated editing technology fused with chloroplast transit peptide (cpTALEN) to site-specifically edit the rpoB gene via Agrobacteria-mediated transformation of tobacco leaf. Transgenic plants showed various degrees of chlorotic phenotype. Repairing damaged plastid DNA resulted in point mutation, large deletion and small inversion surrounding the rpoB gene by homologous recombination and/or microhomology-mediated recombination. In an albino line, microhomology-mediated recombination via a pair of 12-bp direct repeats between rpoC2 and ycf2 genes generated the chimeric ycf2-rpoC2 subgenome, with the level about 3- to 5-fold higher for subgenomic DNA than ycf2. Additionally, the expression of chimeric ycf2-rpoC2 transcripts versus ycf2 mRNA agreed well with the level of corresponding DNA. The ycf2-rpoC2 subgenomic DNA might independently and preferentially replicate in plastids.


Asunto(s)
Reparación del ADN , ADN de Cloroplastos , Edición Génica/métodos , Nicotiana/genética , Fitomejoramiento/métodos , Nucleasas de los Efectores Tipo Activadores de la Transcripción/genética , Recombinación Homóloga , Fenotipo , Plantas Modificadas Genéticamente/genética
10.
Mol Ther Nucleic Acids ; 25: 536-553, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34589276

RESUMEN

Mutant p53 (mutp53) commonly loses its DNA binding affinity to p53 response elements (p53REs) and fails to induce apoptosis fully. However, the p53 mutation does not predict chemoresistance in all subtypes of breast cancers, and the critical determinants remain to be identified. In this study, mutp53 was found to mediate chemotherapy-induced long intergenic noncoding RNA-p21 (lincRNA-p21) expression by targeting the G-quadruplex structure rather than the p53RE on its promoter to promote chemosensitivity. However, estrogen receptor alpha (ERα) suppressed mutp53-mediated lincRNA-p21 expression by hijacking mutp53 to upregulate damaged DNA binding protein 2 (DDB2) transcription for subsequent DNA repair and chemoresistance. Levels of lincRNA-p21 positively correlated with the clinical responses of breast cancer patients to neoadjuvant chemotherapy and had an inverse correlation with the ER status and DDB2 level. In contrast, the carboplatin-induced DDB2 expression was higher in ER-positive breast tumor tissues. These results demonstrated that ER status determines the oncogenic function of mutp53 in chemoresistance by switching its target gene preference from lincRNA-p21 to DDB2 and suggest that induction of lincRNA-p21 and targeting DDB2 would be effective strategies to increase the chemosensitivity of mutp53 breast cancer patients.

11.
Cancer Sci ; 112(10): 4234-4245, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34382727

RESUMEN

Development of acquired resistance to lapatinib, a dual epidermal growth factor receptor (EGFR)/human epidermal growth factor receptor 2 (HER2) tyrosine kinase inhibitor, severely limits the duration of clinical response in advanced HER2-driven breast cancer patients. Although the compensatory activation of the PI3K/Akt survival signal has been proposed to cause acquired lapatinib resistance, comprehensive molecular mechanisms remain required to develop more efficient strategies to circumvent this therapeutic difficulty. In this study, we found that suppression of HER2 by lapatinib still led to Akt inactivation and elevation of FOX3a protein levels, but failed to induce the expression of their downstream pro-apoptotic effector p27kip1 , a cyclin-dependent kinase inhibitor. Elevation of miR-221 was found to contribute to the development of acquired lapatinib resistance by targeting p27kip1 expression. Furthermore, upregulation of miR-221 was mediated by the lapatinib-induced Src family tyrosine kinase and subsequent NF-κB activation. The reversal of miR-221 upregulation and p27kip1 downregulation by a Src inhibitor, dasatinib, can overcome lapatinib resistance. Our study not only identified miRNA-221 as a pivotal factor conferring the acquired resistance of HER2-positive breast cancer cells to lapatinib through negatively regulating p27kip1 expression, but also suggested Src inhibition as a potential strategy to overcome lapatinib resistance.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Resistencia a Antineoplásicos/fisiología , Lapatinib/farmacología , MicroARNs/metabolismo , Receptor ErbB-2/antagonistas & inhibidores , Animales , Neoplasias de la Mama/química , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/efectos de los fármacos , Dasatinib/farmacología , Regulación hacia Abajo/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Proteína Forkhead Box O3/metabolismo , Factor Nuclear 3-gamma del Hepatocito/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/efectos de los fármacos , Análisis por Micromatrices , Subunidad p50 de NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/metabolismo
12.
Front Pharmacol ; 12: 614673, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34267653

RESUMEN

The proviral integration site for moloney murine leukemia virus 1 (Pim1) is a serine/threonine kinase and able to promote cell proliferation, survival and drug resistance. Overexpression of Pim1 has been observed in many cancer types and is associated with the poor prognosis of breast cancer. However, it remains unclear whether Pim1 kinase is a potential therapeutic target for breast cancer patients. In this study, we found that Pim1 expression was strongly associated with HER2 expression and that HER2-overexpressing breast cancer cells were more sensitive to Pim1 inhibitor-induced inhibitions of cell viability and metastatic ability. Mechanistically, Pim1 inhibitor suppressed the expression of HER2 at least in part through transcriptional level. More importantly, Pim1 inhibitor overcame the resistance of breast cancer cells to HER2 tyrosine kinase inhibitor lapatinib. In summary, downregulation of HER2 by targeting Pim1 may be a promising and effective therapeutic approach not only for anti-cancer growth but also for circumventing lapatinib resistance in HER2-positive breast cancer patients.

13.
Data Policy ; 32021.
Artículo en Inglés | MEDLINE | ID: mdl-35083434

RESUMEN

The quality of service in healthcare is constantly challenged by outlier events such as pandemics (i.e., Covid-19) and natural disasters (such as hurricanes and earthquakes). In most cases, such events lead to critical uncertainties in decision-making, as well as in multiple medical and economic aspects at a hospital. External (geographic) or internal factors (medical and managerial) lead to shifts in planning and budgeting, but most importantly, reduce confidence in conventional processes. In some cases, support from other hospitals proves necessary, which exacerbates the planning aspect. This paper presents three data-driven methods that provide data-driven indicators to help healthcare managers organize their economics and identify the most optimum plan for resources allocation and sharing. Conventional decision-making methods fall short in recommending validated policies for managers. Using reinforcement learning, genetic algorithms, traveling salesman, and clustering, we experimented with different healthcare variables and presented tools and outcomes that could be applied at health institutes. Experiments are performed; the results are recorded, evaluated, and presented.

14.
Opt Express ; 28(19): 27727-27735, 2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32988060

RESUMEN

Laser trapping at an interface is a unique platform for aligning and assembling nanomaterials outside the focal spot. In our previous studies, Au nanoparticles form a dynamically evolved assembly outside the focus, leading to the formation of an antenna-like structure with their fluctuating swarms. Herein, we unravel the role of surface plasmon resonance on the swarming phenomena by tuning the trapping laser wavelength concerning the dipole mode for Au nanoparticles of different sizes. We clearly show that the swarm is formed when the laser wavelength is near to the resonance peak of the dipole mode together with an increase in the swarming area. The interpretation is well supported by the scattering spectra and the spatial light scattering profiles from single nanoparticle simulations. These findings indicate that whether the first trapped particle is resonant with trapping laser or not essentially determines the evolution of the swarming.

15.
Transgenic Res ; 29(5-6): 511-527, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32776308

RESUMEN

The ß-glucosidase, which hydrolyzes the ß(1-4) glucosidic linkage of disaccharides, oligosaccharides and glucose-substituted molecules, has been used in many biotechnological applications. The current commercial source of ß-glucosidase is mainly microbial fermentation. Plants have been developed as bioreactors to produce various kinds of proteins including ß-glucosidase because of the potential low cost. Sulfolobus solfataricus is a thermoacidophilic archaeon that can grow optimally at high temperature, around 80 °C, and pH 2-4. We overexpressed the ß-glucosidase gene from S. solfataricus in transgenic tobacco via Agrobacteria-mediated transformation. Three transgenic tobacco lines with ß-glucosidase gene expression driven by the rbcS promoter were obtained, and the recombinant proteins were accumulated in chloroplasts, endoplasmic reticulum and vacuoles up to 1%, 0.6% and 0.3% of total soluble protein, respectively. By stacking the transgenes via crossing distinct transgenic events, the level of ß-glucosidase in plants could further increase. The plant-expressed ß-glucosidase had optimal activity at 80 °C and pH 5-6. In addition, the plant-expressed ß-glucosidase showed high thermostability; on heat pre-treatment at 80 °C for 2 h, approximately 70% residual activity remained. Furthermore, wind-dried leaf tissues of transgenic plants showed good stability in short-term storage at room temperature, with ß-glucosidase activity of about 80% still remaining after 1 week of storage as compared with fresh leaf. Furthermore, we demonstrated the possibility of using the archaebacterial ß-glucosidase gene as a reporter in plants based on alternative ß-galactosidase activity.


Asunto(s)
Nicotiana/genética , Plantas Modificadas Genéticamente/genética , Proteínas Recombinantes/metabolismo , Sulfolobus solfataricus/genética , beta-Glucosidasa/genética , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Celobiosa/metabolismo , Clonación Molecular , Estabilidad de Enzimas , Genes Reporteros , Vectores Genéticos , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Regiones Promotoras Genéticas , Proteínas Recombinantes/genética , Sulfolobus solfataricus/enzimología , Temperatura , Nicotiana/metabolismo , beta-Glucosidasa/metabolismo
16.
Oncol Rep ; 39(2): 703-710, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29207188

RESUMEN

Glycyrrhizic acid (GA), the main component of licorice root extracts, has been shown to suppress cell proliferation and induce apoptosis in various types of cancers. However, the molecular mechanism of its anticancer activity remains poorly understood and warrants further investigation. MDA-MB­231 cells were treated with various concentrations of GA and the cytotoxic effects of GA were determined using the CCK-8 assay. Apoptosis and cell cycle status were detected by flow cytometry. Reactive oxygen species (ROS) levels and mitochondrial membrane potential (∆Ψm) were assessed using DCFDA, MitoSOX and JC-1 staining. Western blot analysis was used to quantify the expression of autophagy-related proteins. In the present study, induction of autophagic cell death was observed in GA-treated MDA-MB­231 cells. Downregulation of p62- and beclin 1-associated proteins occurred after GA treatment, and, the conversion of LC3 and increased ROS without significant changes in caspase­associated proteins and intracellular responses were detected. Furthermore, loss of mitochondria and its membrane potential in cells demonstrated that mitochondria were involved in the GA-regulated MDA-MB-231 cell death. The addition of a pan-caspase inhibitor (z-VAD-fmk) did not suppress the GA-induced apoptotic effect, and GA-induced apoptosis was not accompanied by processing of procaspase-8, -9 and -3. However, GA triggered the translocation of the apoptosis-inducing factor (AIF) from the mitochondria into the nucleus. In contrast, GA-induced LC3 conversion was significantly inhibited by 3 methlyadenine (3MA), an inhibitor of PI3K­regulated autophagy. Therefore, these results suggest that enhancement of both AIF- and LC3-dependent GA-derived ROS generation plays an important role in the inhibition of the growth of MDA-MB-231 human breast cancer cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/metabolismo , Ácido Glicirrínico/farmacología , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Autofagia , Proteínas Relacionadas con la Autofagia/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Ciclo Celular/efectos de los fármacos , Proliferación Celular , Supervivencia Celular/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos
17.
Bot Stud ; 58(1): 38, 2017 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-28916985

RESUMEN

BACKGROUND: RNA editing is a process of post-transcriptional level of gene regulation by nucleotide modification. Previously, the chloroplast DNA of Taiwan endemic moth orchid, P. aphrodite subsp. formosana was determined, and 44 RNA editing sites were identified from 24 plastid protein-coding transcripts of leaf tissue via RT-PCR and then conventional Sanger sequencing. However, the RNA editing status of whole-plastid transcripts in leaf and other distinct tissue types in moth orchids has not been addressed. To sensitively and extensively examine the plastid RNA editing status of moth orchid, RNA-Seq was used to investigate the editing status of whole-plastid transcripts from leaf and floral tissues by mapping the sequence reads to the corresponding cpDNA template. With the threshold of at least 5% C-to-U or U-to-C conversion events observed in sequence reads considered as RNA editing sites. RESULTS: In total, 137 edits with 126 C-to-U and 11 U-to-C conversions, including 93 newly discovered edits, were identified in plastid transcripts, representing an average of 0.09% of the nucleotides examined in moth orchid. Overall, 110 and 106 edits were present in leaf and floral tissues, respectively, with 79 edits in common. As well, 79 edits were involved in protein-coding transcripts, and the 58 nucleotide conversions caused the non-synonymous substitution. At least 32 edits showed significant (≧20%) differential editing between leaf and floral tissues. Finally, RNA editing in trnM is required for the formation of a standard clover-leaf structure. CONCLUSIONS: We identified 137 edits in plastid transcripts of moth orchid, the highest number reported so far in monocots. The consequence of RNA editing in protein-coding transcripts mainly cause the amino acid change and tend to increase the hydrophobicity as well as conservation among plant phylogeny. RNA editing occurred in non-protein-coding transcripts such as tRNA, introns and untranslated regulatory regions could affect the formation and stability of secondary structure, which might play an important role in the regulation of gene expression. Furthermore, some unidentified tissue-specific factors might be required for regulating RNA editing in moth orchid.

18.
Am J Chin Med ; 45(2): 351-368, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28231747

RESUMEN

Saikosaponin a (SSa) is one of the main active components of Bupleurum falcatum. It is commonly used to treat liver injury and fibrosis in traditional Chinese medicine. Our previous study showed that SSa induces apoptosis and inhibits the proliferation of rat hepatic stellate cell (HSC) line HSC-T6. The aim of the present study was to elucidate the mechanism of SSa-mediated apoptosis. Rat HSC cell line HSC-T6 and human HSC cell line LX-2 were used in this study. SSa triggered cell death mainly by apoptosis, as indicated by the typical morphological changes, sub-G1 phase of cell cycle increase, and activation of the caspase-9/caspase-3 cascade. In addition, SSa-induced apoptosis was partially inhibited by the caspase-3 inhibitor Z-DEVD-FMK, suggesting an involvement of caspase-3 dependent and independent pathways. Moreover, SSa upregulated pro-apoptotic proteins [BAK, Bcl-2-associated death promoter (BAD), and p53 upregulated modulator of apoptosis (PUMA)] and downregulated anti-apoptotic proteins (Bcl-2). In the mitochondria, SSa triggered the translocation of BAX and BAK from the cytosol to the outer membrane, resulting in a reduction of mitochondrial functions and membrane potential and subsequent release of apoptotic factors. Therefore, this study demonstrates that SSa induces apoptosis through the intrinsic mitochondrial-dependent pathway in HSCs.


Asunto(s)
Apoptosis/efectos de los fármacos , Células Estrelladas Hepáticas/citología , Mitocondrias/metabolismo , Ácido Oleanólico/análogos & derivados , Saponinas/farmacología , Animales , Apoptosis/genética , Bupleurum , Caspasa 3/metabolismo , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Células Cultivadas , Ácido Oleanólico/farmacología , Ratas , Estimulación Química
19.
ChemMedChem ; 12(1): 19-22, 2017 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-27863054

RESUMEN

Herein we report the 2-nitrobenzenesulfonamide group as a new chemical linker that responds to the difference in redox potential across the cellular membrane, toward the construction of siRNA-polymer conjugates. PEG-conjugated to siRNA via the 2-nitrobenzenesulfonamide group (PEG-sul-siRNA) exhibited highly selective siRNA release under intracellular conditions due to the exclusive presence of the GSH/GST combination in the cell. In addition, siRNA release from PEG-sul-siRNA under extracellular reductive conditions was dramatically suppressed relative to PEG-siRNA conjugates containing a conventional redox-sensitive disulfide linkage (PEG-disulfide-siRNA), indicating the enhanced extracellular stability of the 2-nitrobenzenesulfonamide group. The enhanced gene-silencing effect of PEG-sul-siRNA for cultured cells relative to PEG-siRNA, containing a non-cleavable carboxylic amide linkage (PEG-car-siRNA), confirmed the intracellular release of siRNA via the PEG-sul-siRNA system. These results suggest that the 2-nitrobenzenesulfonamide group could be a suitable chemical linker alternative to the conventional disulfide group.


Asunto(s)
Polímeros/química , Polímeros/metabolismo , ARN Interferente Pequeño/química , ARN Interferente Pequeño/metabolismo , Sulfonamidas/química , Humanos
20.
J Biosci ; 42(3): 439-448, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29358557

RESUMEN

Diabetes patients associated with liver disease carry a significant risk of morbidity and mortality. Cinnamon has been reported to reduce fructose-induced oxidative stress in the rat liver. However, the mechanism by which cinnamon protects the liver in a high-saccharide environment remains to be investigated. HepG2 cells were cultured with 30 mM D-ribose to mimic the high-oxidative-stress environment, typical of a liver in a diabetic patient. Three different chemical types of C. osmophloeum ethanol extracts (CEEs) were added in HepG2 culture media and the administration of all three CEEs protected HepG2 cells from D-ribose damage and increased cell survival by approximately 20 percent. Exclusively, the transcript variant 1 of the ghrelin gene, but not variant 3, was 2-3 times induced by the addition of these CEEs. Moreover, the mRNAs of ghrelin processing enzyme, furin, and mboat4 were detected in HepG2 cells. The ghrelin hormones in the culture media were increased 4-9 times by the addition of CEEs. The protective effects of ghrelin on HepG2 cells in D-ribose environment were further confirmed by recombinant ghrelin transfection. We conclude that the CEEs induce ghrelin gene expression and protect HepG2 cells from D-ribose-induced oxidative damage through ghrelin signalling.


Asunto(s)
Antioxidantes/farmacología , Cinnamomum/química , Ghrelina/agonistas , Extractos Vegetales/farmacología , ARN Mensajero/agonistas , Aciltransferasas/genética , Aciltransferasas/metabolismo , Antioxidantes/química , Supervivencia Celular/efectos de los fármacos , Etanol/química , Furina/genética , Furina/metabolismo , Regulación de la Expresión Génica , Ghrelina/genética , Ghrelina/metabolismo , Células Hep G2 , Humanos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ribosa/antagonistas & inhibidores , Ribosa/farmacología , Transducción de Señal , Solventes/química
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