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1.
JMIR Form Res ; 7: e46494, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37883144

RESUMO

BACKGROUND: Adolescents experience relatively more stress than other populations as they are facing rapid physical changes and adapting to complex social environments. However, access for this population to professional service providers is limited. Therefore, there is an increasing need for access to mental health services and new mental health care resources tailored to adolescents. OBJECTIVE: The aim of this study was to evaluate the functionality and effectiveness of a school digital mental health clinic (DMHC) created by a Chinese psychiatric hospital and provided to secondary school students for a trial. METHODS: The trial period of the DMHC was from January to July 2021 at three secondary schools in Taizhou City, China. Under a collaborative agreement between the local educational bureau and provider, use of the DMHC was free to all students, teachers, and staff of the schools. The functionality of the DMHC was compared with existing digital health interventions introduced in the literature and its effectiveness was quantitatively analyzed in terms of the volume of received counseling calls, number of calls per 100 students, length and time of calls, and reasons for the calls. The mini course video views were analyzed by topics and viewing time. RESULTS: The design functions of the DMHC are well aligned with required factors defined in the literature. The first advantage of this DMHC is its high accessibility to students in the three schools. All functions of the DMHC are free to use by students, thereby eliminating the economic barriers to seeking and receiving care. Students can receive virtual counseling during or after regular working hours. Acceptability of the DHMC was further ensured by the full support from a national top-tier mental health facility. Any audio or video call from a student user would connect them to a live, qualified professional (ie, a psychiatrist or psychologist). Options are provided to view and listen to resources for stress relief or tips to help address mental health needs. The major reasons for the counseling calls included difficulties in learning, interpersonal relationships, and emotional distress. The three topics with the highest level of interest for the mini course videos were emotional assistance, personal growth, and family member relationships. The DMHC served as an effective tool for crisis prevention and intervention during nonworking hours as most of the live calls and mini video viewing occurred after school or over the weekend. Furthermore, the DMHC helped three students at high risk for suicide and self-injury through live-call intervention. CONCLUSIONS: The DMHC is an effective complementary solution to improve access to professional mental health care facilities, especially during nonworking hours, thereby helping adolescents meet their mental health needs. Extension of the DMHC into more schools and other settings is recommended.

2.
Biochem Genet ; 61(6): 2672-2690, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37222961

RESUMO

Gastric cancer (GC) is a common malignant tumor, posing a great threat to human's health and life. Previous studies have suggested aberrant expression of long non-coding RNAs (lncRNAs) in GC. This study elucidated the effects of lncRNA ACTA2-AS1 on the biological characteristics of GC. Gene expression in stomach adenocarcinoma (STAD) samples compared with normal tissues and the correlation between gene expression and prognosis of STAD patients were analyzed using bioinformatic tools. Gene expression at protein and mRNA levels in GC and normal cells was tested by western blotting and RT-qPCR. The subcellular localization of ACTA2-AS1 in AGS and HGC27 cells was identified by nuclear-cytoplasmic fractionation and FISH assay. EdU, CCK-8, flow cytometry analysis, TUNEL staining assays were conducted to evaluate the role of ACTA2-AS1 and ESRRB on GC cellular behaviors. The binding relationship among ACTA2-AS1, miR-6720-5p and ESRRB was verified by RNA pulldown, luciferase reporter assay and RIP assay. LncRNA ACTA2-AS1 was underexpressed in GC tissues and cell lines. ACTA2-AS1 elevation suppressed GC cell proliferation and induced apoptosis. Mechanistically, ACTA2-AS1 directly bound to miR-6720-5p and subsequently promoted the expression of target gene ESRRB in GC cells. Furthermore, ESRRB knockdown reversed the influence of ACTA2-AS1 overexpression on GC proliferation and apoptosis. ACTA2-AS1 plays an antioncogenic role in GC via binding with miR-6720-5p to regulate ESRRB expression.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Receptores de Estrogênio/genética , Actinas/genética
3.
Int J Biol Sci ; 18(13): 4932-4949, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35982908

RESUMO

Little is known about the oncogenic role or biological function of copine Ⅷ (CPNE8) in gastric cancer (GC). Based on TCGA database, we screened for CPNE8 and analyzed the expression of CPNE8 in GC. The correlations between CPNE8 and clinical features were analyzed using TCGA and GEO databases. The prognostic value of CPNE8 was assessed using Cox analysis and Kaplan-Meier curves. The results showed that increased expression of CPNE8 was positively correlated with metastasis and can be considered an independent prognostic risk factor for poor survival. We found that CPNE8 can promote cell proliferation, migration, and invasiveness in GC using in vitro and in vivo experiments. Our study demonstrated that CPNE8 promotes tumor progression via regulation of focal adhesion, and these effects can be rescued by focal adhesion kinase (FAK) inhibitor GSK2256098 or knockdown of FAK. In addition, CPNE8 was correlated significantly with the infiltration of cancer-associated fibroblasts and immune cells, as demonstrated by various algorithms, and high CPNE8 expression predicted poor efficacy of immune checkpoint therapy. Our findings suggest that CPNE8 modulates focal adhesion and tumor microenvironment to promote GC progression and invasiveness and could serve as a novel prognostic biomarker in GC.


Assuntos
Proteínas de Transporte , Neoplasias Gástricas , Microambiente Tumoral , Proteínas de Transporte/genética , Movimento Celular , Quinase 1 de Adesão Focal/metabolismo , Adesões Focais/metabolismo , Adesões Focais/patologia , Humanos , Invasividade Neoplásica/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Microambiente Tumoral/genética
4.
Oncogenesis ; 11(1): 21, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35487890

RESUMO

Little is known about the biological functions of neuron-specific enolase (NSE) as a specific biomarker for small-cell lung cancer (SCLC). Herein, we elucidate the effect and mechanism of NSE on SCLC stem cell-like characteristics. Upregulated NSE expression was observed in spheroid cells. The gain-of-function and loss-of-function approaches demonstrated that modulation of NSE positively regulated cell proliferation, drug resistance, spherical clone formation, tumor growth, and stem cell-like characteristics of SCLC cells. Mechanistic studies revealed that NSE might downregulate the expression of neuroblastoma suppressor of tumorigenicity 1 (NBL1) by interacting with NBL1, thereby attenuating the competitive inhibitory effect of NBL1 on BMP2 and enhancing the interaction between BMP2 and BMPR1A; this, in turn, may activate the BMP2/Smad/ID1 pathway and promote SCLC stem cell-like characteristics. Moreover, overexpression of NBL1or knockdown of BMP2 rescued the NSE-induced stem cell-like characteristics. In clinical specimens, NSE expression was positively associated with ALDH1A1 expression and negatively correlated with NBL1 expression. High NSE and ALDH1A1 expressions and low NBL1 expression were correlated with poor prognosis in patients with SCLC. In summary, our study demonstrated that NSE promoted stem cell-like characteristics of SCLC via NBL1 and the activation of the BMP2/Smad/ID1 pathway.

5.
Neoplasma ; 69(2): 303-310, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35068161

RESUMO

The release of circulating tumor cells (CTCs) into vasculature is an early event in the metastatic process and the detection of CTCs has been widely used clinically. In addition, cancer stem cells (CSCs) are the source of distant metastasis. However, the relationship between CTCs and CSCs in nasopharyngeal carcinoma (NPC) patients was largely unknown. A total of 93 NPC patients were enrolled in this study. The CTCs in the peripheral blood were detected. The expression of ALDH1A1 in the tumor tissues of the corresponding patients was detected using immunohistochemistry (IHC). The prognostic value of CTCs level and the correlation with the expression of ALDH1A1 was evaluated. Data showed that the detection of CTCs was positively correlated with metastasis (p<0.001). The positive detection of CTCs was also associated with poor overall survival (p=0.025). CTCs ≥2 demonstrated good specificity and sensitivity in predicting distant metastasis, while CTCs ≥8 demonstrated better specificity and sensitivity in predicting prognosis than CTCs ≥2. Furthermore, we found that there was a positive relationship between the detection of CTCs and the expression of ALDH1A1 (p=0.001). The prognosis analysis also demonstrated that high ALDH1A1 expression was correlated with poor overall survival (p=0.006). Our study demonstrated a positive correlation between the CTCs and the expression of CSCs, both were positively correlated with metastasis and poor prognosis. These results indicated that the CTCs might indirectly reflect the expression of CSCs.


Assuntos
Neoplasias Nasofaríngeas , Células Neoplásicas Circulantes , Biomarcadores Tumorais/metabolismo , Humanos , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/patologia , Células Neoplásicas Circulantes/metabolismo , Células-Tronco Neoplásicas/patologia , Prognóstico
6.
Transl Oncol ; 14(4): 101039, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33618068

RESUMO

Neuron-specific enolase (NSE) has been used as a specific biomarker for small cell lung cancer (SCLC) patients. Nevertheless, the biological function and mechanism of NSE in SCLC are still unclear. In this study, we clarified the role of NSE in the progression of SCLC and found that NSE expression was positively correlated with distant metastasis. Functional analysis showed that overexpression of NSE promoted migration and invasion of SCLC cells. Mechanism analysis showed that NSE overexpression induced epithelial-mesenchymal transition (EMT) of SCLC cells. Moreover, overexpression of NSE increased the protein expression of ß-catenin and its downstream target genes, and silencing ß-catenin eliminated NSE-mediated cell migration, invasion and EMT process. Furthermore, NSE interacted with ß-catenin and inhibited the degradation of ß-catenin. Besides, the animal experiments also indicated that NSE could promote the EMT process and distant metastasis of SCLC cells in vivo. In summary, our results revealed that NSE could promote the EMT process of SCLC cells by activating the Wnt/ß-catenin signaling pathway, thereby promoting cell migration, invasion and distant metastasis, which might serve as a potential target for the therapy of SCLC patients.

7.
Int J Med Sci ; 17(17): 2718-2727, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162799

RESUMO

Lung squamous cell carcinoma (LUSCC), as the major type of lung cancer, has high morbidity and mortality rates. The prognostic markers for LUSCC are much fewer than lung adenocarcinoma. Besides, protein biomarkers have advantages of economy, accuracy and stability. The aim of this study was to construct a protein prognostic model for LUSCC. The protein expression data of LUSCC were downloaded from The Cancer Protein Atlas (TCPA) database. Clinical data of LUSCC patients were downloaded from The Cancer Genome Atlas (TCGA) database. A total of 237 proteins were identified from 325 cases of LUSCC patients based on the TCPA and TCGA database. According to Kaplan-Meier survival analysis, univariate and multivariate Cox analysis, a prognostic prediction model was established which was consisted of 6 proteins (CHK1_pS345, CHK2, IRS1, PAXILLIN, BRCA2 and BRAF_pS445). After calculating the risk values of each patient according to the coefficient of each protein in the risk model, the LUSCC patients were divided into high risk group and low risk group. The survival analysis demonstrated that there was significant difference between these two groups (p= 4.877e-05). The area under the curve (AUC) value of the receiver operating characteristic (ROC) curve was 0.699, which suggesting that the prognostic risk model could effectively predict the survival of LUSCC patients. Univariate and multivariate analysis indicated that this prognostic model could be used as independent prognosis factors for LUSCC patients. Proteins co-expression analysis showed that there were 21 proteins co-expressed with the proteins in the risk model. In conclusion, our study constructed a protein prognostic model, which could effectively predict the prognosis of LUSCC patients.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/mortalidade , Perfilação da Expressão Gênica , Neoplasias Pulmonares/mortalidade , Análise Serial de Proteínas/estatística & dados numéricos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Estudos de Coortes , Conjuntos de Dados como Assunto , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Estadiamento de Neoplasias , Prognóstico , Curva ROC , Medição de Risco/métodos
8.
Int J Med Sci ; 17(7): 912-920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308544

RESUMO

Aim: CC chemokine receptor 9 (CCR9) interacts with its exclusive ligand CCL25, resulting in promoting tumor progression and metastasis. However, the effect and mechanisms of CCR9 on lung adenocarcinoma distant metastasis remain largely unknown. To preliminary clarify the underlying mechanisms, we investigate the correlation between CCR9 and ALDH1A1+cancer stem cells (CSCs), as well as the effect of CCR9 on the migration and invasion of CSCs. Methods: Immunohistochemistry was performed to detect the expression of CCR9 in lung adenocarcinoma tissues. The correlations of CCR9 with distant metastasis and overall survival were investigated. Serial paraffin-embedded tissue blocks were used to detect ALDH1A1+CSCs expression. The correlations between CCR9 expression and ALDH1A1+CSCs were evaluated. We further studied the effect of CCR9/CCL25 on the migration and invasion of CSCs using transwell assays. Results: There were positive correlations between CCR9 expression and distant metastasis, as well as poor overall survival. Patients with high CCR9 expression were more likely to develop distant metastasis and demonstrated poorer overall survival than patients with low CCR9 expression. In addition, there was positive correlation between the expression of CCR9 and ALDH1A1 in the same tumor microenvironment. ALDHhigh CSCs demonstrated enhanced expression of CCR9 than ALDHlow cells. Further transwell assays demonstrated that the numbers of CSCs migrated or invaded in response to CCL25 were more than that without CCL25 stimulation. Additional application of anti-CCR9 antibody reversed the CCL25-induced migration and invasion of CSCs. Conclusions: In summary, our study demonstrated that CCR9/CCL25 promoted the migration and invasion of CSCs, which might contribute to distant metastasis and poor overall survival. Our findings provided evidence that CCR9/CCL25 could be used as novel therapeutic targets for lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptores CCR/metabolismo , Células A549 , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/mortalidade , Adulto , Idoso , Família Aldeído Desidrogenase 1/metabolismo , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Receptores CCR/genética , Retinal Desidrogenase/metabolismo , Células Tumorais Cultivadas
9.
Int J Biol Sci ; 16(6): 935-946, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32140063

RESUMO

Lymphoma is a malignant disease of the hematopoietic system that typically affects B cells. The up-regulation of miR-148b is associated with radiosensitization in B-cell lymphoma (BCL). This study aimed to explore the role of miR-148b in regulating the radiosensitivity of BCL cells and to investigate the underlying mechanism. miR-148b directly targeted Bcl-w, decreased the cell viability and colony formation, while promoted apoptosis, in irradiated BCL cells. These changes were accompanied by decreased mitochondrial membrane potential, release of cytochrome C, increased levels of the cleaved caspase 9 and caspase 3, and increased expression of other proteins related to the mitochondrial apoptosis pathway. These effects of miR-148b were effectively inhibited by Bcl-w. In addition, miR-148b inhibited the growth of tumors in nude mice implanted with xenografts of irradiated Raji cells. In patients with BCL, levels of miR-148b were downregulated, while levels of Bcl-w were upregulated; a significant negative correlation between levels of miR-148b and Bcl-w was confirmed. Taken together, these experiments showed that miR-148b promoted radiation-induced apoptosis in BCL cells by targeting anti-apoptotic Bcl-w. miR-148b might be used as a marker to predict the radiosensitivity of BCL.


Assuntos
MicroRNAs/metabolismo , Adulto , Idoso , Animais , Apoptose/genética , Apoptose/fisiologia , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Lentivirus/genética , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Linfoma de Células B , Masculino , Potencial da Membrana Mitocondrial/genética , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Fases de Leitura Aberta/genética , Reação em Cadeia da Polimerase em Tempo Real
10.
Onco Targets Ther ; 12: 2553-2561, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31040698

RESUMO

AIM: The human ubiquitination factor E4B (UBE4B) gene is frequently amplified in some solid cancers. However, the role of UBE4B in nasopharyngeal carcinoma (NPC) has not yet been investigated. METHODS: Firstly, we analyzed the expression of UBE4B in NPC samples using real-time quantitative PCR and Western blot analysis. After knocking down UBE4B using small interfering RNA technology, the functions of UBE4B on cell proliferation, apoptosis, and cell cycle, as well as underlying mechanism, were investigated. RESULTS: Compared with matched adjacent non-tumor tissues, both protein and mRNA levels of UBE4B were much higher in most NPC cancerous specimens. Deficiency of UBE4B could significantly inhibit tumor cell growth and induce cell apoptosis. Knocking down UBE4B could promote the expression of cleaved caspase3 and p53, and inhibition of caspase3 could prevent cell apoptosis induced by the deficiency of UBE4B. CONCLUSION: These results indicate that expression of UBE4B was higher in most NPC tissues compared to adjacent non-tumoral tissues, and that knockdown of UBE4B inhibited the cell growth and induced apoptosis in NPC cells. This process was regulated by the activation of caspase3 and p53. Thus, UBE4B gene might act as a potential molecular target to develop novel strategy for NPC patients.

11.
BMC Cancer ; 19(1): 209, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30849960

RESUMO

BACKGROUND: MicroRNA-148b (miR-148b) has been detected in various types of tumors, and is generally viewed as a tumor suppressor. Our previous study found the decreased expression of miR-148b in human non small cell lung cancer (NSCLC) specimens and cell lines. However, the underlying mechanisms of miR-148b in regulating tumor progression remain unclear. METHODS: Firstly animal experiments were performed to verify whether miR-148b could inhibit the tumor growth. Then, the underlying mechanisms were studied by transfecting recombinant plasmids containing a miR-148b mimic or a negative control (NC) mimic (shRNA control) into NSCLC cell lines PC14/B and A549 cells. Tumor cells transfected with unpackaged lentiviral vectors was used as blank control. Cell proliferation capabilities were measured by using CCK-8 kit and colony formation assay. Cell cycle arrest was compared to clarify the mechanism underlying the tumor cell proliferation. Annexin V-FITC Apoptosis Detection kit was applied to investigate the effect of miR-148b on cell apoptosis. Furthermore, western blot analysis were performed to study the targeting pathway. RESULTS: We found that over-expression of miR148b could significantly inhibit tumor growth, while knocking down miR148b could obviously promote tumor growth. Further experiment showed that miR-148b inhibited tumor cell proliferation. Besides, over-expression of miR148b decreased the G2/M phase population of the cell cycle by preventing NSCLC cells from entering the mitotic phase and enhanced tumor cell apoptosis. Further western blot analysis indicated that miR148b could inhibit mitogen-activated protein kinase/Jun N-terminal kinase (MAPK/JNK) signaling by decreasing the expression of phosphorylated (p) JNK. CONCLUSIONS: These results demonstrate that miR-148b could inhibit the tumor growth and act as tumor suppressor by inhibiting the proliferation and inducing apoptosis of NSCLC cells by blocking the MAPK/JNK pathway.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases , MicroRNAs/genética , Animais , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Fosforilação , Interferência de RNA
12.
Oncotarget ; 7(16): 21853-64, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-26942702

RESUMO

We have previously reported that the accumulation of IL-17-producing cells could mediate tumor protective immunity by promoting the migration of NK cells, T cells and dendritic cells in esophageal squamous cell carcinoma (ESCC) patients. However, there were no reports concerning the effect of IL-17A on tumor infiltrating B cells. In this study, we investigated the accumulation of CD20+ B cells in the ESCC tumor nests and further addressed the effect of IL-17A on the migration and cytotoxicity of B cells. There was positive correlation between the levels of CD20+ B cells and IL-17+ cells. IL-17A could promote the ESCC tumor cells to produce more chemokines CCL2, CCL20 and CXCL13, which were associated with the migration of B cells. In addition, IL-17A enhanced the IgG-mediated antibody and complement mediated cytotoxicity of B cells against tumor cells. IL-17A-stimulated B cells gained more effective direct killing capability through enhanced expression of Granzyme B and FasL. The effect of IL-17A on the migration and cytotoxicity of B cells was IL-17A pathway dependent, which could be inhibited by IL-17A inhibitor. This study provides further understanding of the roles of IL-17A in humoral response, which may contribute to the development of novel tumor immunotherapy strategy.


Assuntos
Linfócitos B/imunologia , Carcinoma de Células Escamosas/imunologia , Movimento Celular/imunologia , Citotoxicidade Imunológica/imunologia , Neoplasias Esofágicas/imunologia , Interleucina-17/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Antígenos CD20/imunologia , Antígenos CD20/metabolismo , Linfócitos B/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Humanos , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade
13.
Ying Yong Sheng Tai Xue Bao ; 25(7): 1849-56, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25345031

RESUMO

Two robust Pinus taiwanensis Hayata tree-ring width chronologies were developed at high elevation sites in Jiulongshan Natural Conservation Area (JLS01), southeastern Zhejiang Province and Guniujiang (GNJ01), southern Anhui Province, China. The reliable period was 1884-2010 for JLS01 and 1837-2008 for GNJ01, based on subsample signal strength (SSS) threshold value of 0.8. Meteorological data were monthly mean temperature, monthly total precipitation and monthly mean relative humidity, monthly total cloud cover, as well as monthly sunshine duration. The data from the meteorological stations around the sampling sites were averaged to represent regional climate, which were used in the correlation analyses with the tree-ring chronologies. The correlation analyses indicated that summer (prior June-July and current June) hydrothermal condition was the main limiting factor on radial tree growth at the two high elevation sites. For JLS01 chronology, significant positive correlations were found with prior June-July temperature and sunshine duration, significant negative correlations with prior June-July and current June precipitation and relative hu- midity, and total cloud cover of prior July. GNJ01 chronology was significantly positively correlated with prior July temperature as well as prior July and current June sunshine duration, negatively correlated with prior July and current June precipitation and relative humidity, as well as total cloud cover of prior June. These results showed that relatively high temperature could promote radial growth, whereas high precipitation, together with high relative humidity, high cloud cover and low sunshine duration, could limit the photosynthesis and thus restrain the radial tree growth.


Assuntos
Clima , Pinus/crescimento & desenvolvimento , Altitude , China , Umidade , Fotossíntese , Estações do Ano , Temperatura , Árvores/crescimento & desenvolvimento
14.
Biochem Biophys Res Commun ; 329(3): 1026-30, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15752758

RESUMO

RNA mediated interference has emerged as a powerful tool in controlling gene expression in mammalian cells. We investigated the gene silencing properties of six thiophosphate substituted siRNAs (all based on a commercial luciferase medium silencer) compared to that of unmodified siRNA. We also examined the cytotoxicity and dose-response using several thiophosphate modified siRNAs with unmodified siRNA. Our results show that two thiophosphate siRNA sequences convert from medium to high silencers with the addition of four randomly placed thiophosphates. Both thiophosphate siRNAs have a statistically significant difference in luciferase gene silencing (5% and 6% activity) relative to the unmodified native medium silencer referred to as siRNA-2 (18% activity) and four other thiophosphate siRNAs that maintain their medium silencing capability. This indicates that specific thiophosphate substitutions may alter native siRNA function. Further, this shows that thiophosphate siRNAs with the same nucleotide sequence but with different sulfur modification positions have different silencing effects. Both the native siRNA and the thio siRNAs showed a concentration dependent relationship, i.e., with concentration increase, the luciferase gene silencing effect also increased. Confirming cytotoxicity experiments showed no significant changes when HeLa cells were treated with 10nM thiophosphate siRNAs over the course of several days. These results suggest that specific placement of thiophosphates could play an important role in the development of siRNAs as therapeutics by engineering in properties such as strength of binding, nuclease sensitivity, and ultimately efficacy.


Assuntos
Inativação Gênica/fisiologia , Engenharia Genética/métodos , Mutagênese Sítio-Dirigida/genética , Fosfatos/química , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Transfecção/métodos , Regulação da Expressão Gênica/genética , Células HeLa , Humanos , Relação Estrutura-Atividade
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