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1.
Environ Res ; 252(Pt 2): 118904, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38614203

RESUMEN

CH4 serves as an important greenhouse gas, yet limited knowledge is available in global and regional CH4 cycling, particularly in widely distributed karst terrain. In this study, we investigated an upland in Puding Karst Ecosystem Research Station, and explored CH4 concentration and/or flux in atmosphere, soil and cave using a closed static chamber method and an eddy covariance system. Meanwhile, we monitored atmospheric temperature, precipitation, temperature and wind velocity in the cave entrance. The results demonstrated that atmospheric CH4 and actual soil CH4 fluxes in the source area of eddy covariance system were -0.19 ± 8.64 nmols-1m-2 and -0.16 nmols-1m-2 respectively. The CH4 concentrations in Shawan Cave exhibited 10 âˆ¼ 100-fold lower than that of the external atmosphere. CH4 oxidation rate dominated by methane-oxidizing bacteria was 1.98 nmols-1m-2 in Shawan Cave when it combined with temperature difference between cave and external atmosphere. Therefore, CH4 sink in global karst subterranean spaces was estimated at 106.2 Tg CH4 yr-1. We supplemented an understanding of CH4 cycling paths and fluxes in karst terrain, as well as CH4 sinks in karst subterranean space. Further works require to establish a karst ecosystem observation network to conduct long-term integrated studies on CH4 fluxes regarding atmosphere, soils, plants and caves.


Asunto(s)
Atmósfera , Cuevas , Metano , Suelo , Metano/análisis , Metano/metabolismo , Atmósfera/química , Suelo/química , Monitoreo del Ambiente/métodos , Microbiología del Suelo , Contaminantes Atmosféricos/análisis
2.
Artículo en Inglés | MEDLINE | ID: mdl-38466061

RESUMEN

Background: In recent years, Tiaoshen acupuncture in Traditional Chinese Medicine (TCM) has been employed for treating patients with insomnia, but the clinical efficacy remains to be substantiated. Objective: To assess the efficacy and safety of acupuncture in treating insomnia using the Tiaoshen method in TCM. Design: A systematic review and meta-analysis was conducted. Setting: The research was conducted in Shenzhen. Methods: Electronic databases, including Chinese National Knowledge Infrastructure (CNKI), Wanfang, SinoMed, Weipu, PubMed, Web of Science, EMBASE, and Cochrane databases, were retrieved up to September 15, 2023. Randomized controlled trials (RCTs) meeting inclusion criteria were screened. Quality assessment of included articles was performed using the Cochrane Risk of Bias tool. Valid data were then extracted and analyzed via meta-analysis using Review Manager 5.3. The study was registered in the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY), 2023100051. Results: A total of 13 articles were included, comprising 849 patients with insomnia (diagnosed as chronic insomnia or primary insomnia). Meta-analysis results indicated that acupuncture with the Tiaoshen method could decrease the Pittsburgh Sleep Quality Index (PSQI) score [RR=-3.03, 95% CI (-3.73, -2.33), P < .00001], hyperarousal (HAS) scale score [RR=-7.75, 95% CI (-12.29, -3.22), P < .0008], and fatigue scale-14 (FS-14) score [RR=-2.11, 95% CI (-2.83, -1.38), P < .00001] compared with superficial acupuncture on non-effective acupoints or conventional acupuncture manipulation. Additionally, acupuncture with the Tiaoshen method demonstrated safety. However, the funnel plot suggested the presence of publication bias. Conclusions: Acupuncture with the Tiaoshen method could enhance sleep quality and efficiency. Due to the low quality of some literature, further high-quality RCTs are needed to improve the level of evidence.

3.
Nano Lett ; 23(21): 9740-9747, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37879097

RESUMEN

Exciton localization through nanoscale strain has been used to create highly efficient single-photon emitters (SPEs) in 2D materials. However, the strong Coulomb interactions between excitons can lead to nonradiative recombination through exciton-exciton annihilation, negatively impacting SPE performance. Here, we investigate the effect of Coulomb interactions on the brightness, single photon purity, and operating temperatures of strain-localized GaSe SPEs by using electrostatic doping. By gating GaSe to the charge neutrality point, the exciton-exciton annihilation nonradiative pathway is suppressed, leading to ∼60% improvement of emission intensity and an enhancement of the single photon purity g(2)(0) from 0.55 to 0.28. The operating temperature also increased from 4.5 K to 85 K consequently. This research provides insight into many-body interactions in excitons confined by nanoscale strain and lays the groundwork for the optimization of SPEs for optoelectronics and quantum photonics.

4.
Bioinformatics ; 38(5): 1473-1476, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34864890

RESUMEN

SUMMARY: Pathway analysis is widely used in genomics and omics research, but the data visualization has been highly limited in function, pathway coverage and data format. Here, we develop SBGNview a comprehensive R package to address these needs. By adopting the standard SBGN format, SBGNview greatly extend the coverage of pathway-based analysis and data visualization to essentially all major pathway databases beyond KEGG, including 5200 reference pathways and over 3000 species. In addition, SBGNview substantially extends or exceeds current tools (esp. Pathview) in both design and function, including standard input format (SBGN), high-quality output graphics (SVG format) convenient for both interpretation and further update, and flexible and open-end workflow for iterative editing and interactive visualization (Highlighter module). In addition to pathway analysis and data visualization, SBGNview provides essential infrastructure for SBGN data manipulation and processing. AVAILABILITY AND IMPLEMENTATION: The data underlying this article are available as part of the SBGNview package is available on both GitHub and Bioconductor: https://github.com/datapplab/SBGNview, https://bioconductor.org/packages/SBGNview. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Genómica , Programas Informáticos , Visualización de Datos , Bases de Datos Factuales , Análisis de Datos
5.
Environ Res ; 212(Pt B): 113338, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35447153

RESUMEN

Leachate from wet phosphogypsum (PG) stack should be properly managed to mitigate the negative environmental impact of phosphoric industry. Accurate prediction of leachate amount is the prerequisite for efficient leachate management. In this study, a model using water balance analysis to predict leachate production from wet PG stack is established. The extruded water, which is related to PG deformation, is innovatively introduced as a variable in the model to account for the porewater's contribution. Model simulation suggested that at the early stage, fresh water need to be added to PG to facilitate the transfer or PG slurries; however, as the leachate accumulates in the tailings pond, a net discharge of PG is required starting at the fourth year for the studied PG stack. Model simulation also indicated that the leachate generation increased gradually over time and that the leachate generation in each month could deviate from the average leachate generation during the life cycle of the stack. The model output matches with measured values reasonably well, which confirmed the model's accuracy. Sensitivity analysis indicated that average precipitation and evaporation are the two most important factors that determine leachate generation rate. Monthly leachate generation rates vary significantly within the year, as the precipitation and evaporation vary in different seasons. The highest leachate generation rates were reached in rainy seasons and the lowest rates were reached in wintery months. This study could be used to optimize the PG leachate managements and to mitigate the PG related pollution to the environment.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Sulfato de Calcio , Modelos Teóricos , Fósforo , Agua , Contaminantes Químicos del Agua/análisis
6.
JAMA ; 328(8): 728-736, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35997729

RESUMEN

Importance: Concurrent chemoradiotherapy has been the standard treatment for stage II nasopharyngeal carcinoma (NPC) based on data using 2-dimensional conventional radiotherapy. There is limited evidence for the role of chemotherapy with use of intensity-modulated radiation therapy (IMRT). Objective: To assess whether concurrent chemotherapy can be safely omitted for patients with low-risk stage II/T3N0 NPC treated with IMRT. Design, Setting, and Participants: This multicenter, open-label, randomized, phase 3, noninferiority clinical trial was conducted at 5 Chinese hospitals, including 341 adult patients with low-risk NPC, defined as stage II/T3N0M0 without adverse features (all nodes <3 cm, no level IV/Vb nodes; no extranodal extension; Epstein-Barr virus DNA <4000 copies/mL), with enrollment between November 2015 and August 2020. The final date of follow-up was March 15, 2022. Interventions: Patients were randomly assigned to receive IMRT alone (n = 172) or concurrent chemoradiotherapy (IMRT with cisplatin, 100 mg/m2 every 3 weeks for 3 cycles [n = 169]). Main Outcomes and Measures: The primary end point was 3-year failure-free survival (time from randomization to any disease relapse or death), with a noninferiority margin of 10%. Secondary end points comprised overall survival, locoregional relapse-free survival, distant metastasis-free survival, adverse events, and health-related quality of life (QOL) measured by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (QLQ-C30; range, 0-100 points; minimum clinically important difference ≥10 for physical function, symptom control, or health-related QOL; higher score indicates better functioning and global health status or worse symptoms). Results: Among 341 randomized patients (mean [SD] age, 48 [10] years; 30% women), 334 (98.0%) completed the trial. Median follow-up was 46 months (IQR, 34-58). Three-year failure-free survival was 90.5% for the IMRT-alone group vs 91.9% for the concurrent chemoradiotherapy group (difference, -1.4%; 1-sided 95% CI, -7.4% to ∞; P value for noninferiority, <.001). No significant differences were observed between groups in overall survival, locoregional relapse, or distant metastasis. The IMRT-alone group experienced a significantly lower incidence of grade 3 to 4 adverse events (17% vs 46%; difference, -29% [95% CI, -39% to -20%]), including hematologic toxicities (leukopenia, neutropenia) and nonhematologic toxicities (nausea, vomiting, anorexia, weight loss, mucositis). The IMRT-alone group had significantly better QOL scores during radiotherapy including the domains of global health status, social functioning, fatigue, nausea and vomiting, pain, insomnia, appetite loss, and constipation. Conclusions and Relevance: Among patients with low-risk NPC, treatment with IMRT alone resulted in 3-year failure-free survival that was not inferior to concurrent chemoradiotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT02633202.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Quimioradioterapia , Cisplatino , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Infecciones por Virus de Epstein-Barr/complicaciones , Femenino , Herpesvirus Humano 4 , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/etiología , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/etiología , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/radioterapia , Calidad de Vida , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos
7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(3): 229-235, 2020 Mar 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32386012

RESUMEN

OBJECTIVES: To design a standardized imaging diagnostic reporting mode for screening coronavirus disease 2019 (COVID-19), and to prospectively verify its effectiveness in clinical practice. METHODS: A new classification and standardized imaging diagnosis report mode of viral pneumonia was established by studying and summarizing the imaging findings of various kinds of viral pneumonia, combining with lesion density, interstitial changes, pleural effusion, lymph nodes, and some special signs. After systematic training, the radiologist experienced clinical practice for screening CT features. COVID-19 cases were screened retrospectively in the single-center. The confirmed cases were verified, and the diagnostic efficacy of the standardized imaging reporting system in screening COVID-19 was tested. RESULTS: There were 912 patients in this stage receiving the screening imaging examination. Of them, 190 patients were screened in the report mode and 30 patients were diagnosed as COVID-19. The CT manifestation of COVID-19 was characterized by pure ground glass lesions or with a few solid components, predominant subpleural distribution, no lymph node enlargement and pleural effusion, and often with paving-way sign and air bronchus sign. In combination with the above signs, the diagnostic efficacy of COVID-19 was 0.942. CONCLUSIONS: The standardized imaging diagnosis report mode based on COVID-19 chest image features is effective and practical, which should be popularized.


Asunto(s)
Betacoronavirus , COVID-19 , Infecciones por Coronavirus/diagnóstico , Humanos , Pandemias , Neumonía Viral/diagnóstico , Estudios Retrospectivos , SARS-CoV-2 , Tomografía Computarizada por Rayos X
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(3): 275-279, 2020 Mar 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32386019

RESUMEN

Although continuous outbreak of coronavirus disease 2019, it has been widely reported, there were few reports regarding family cases. We reported a group of family cluster outbreak cases confirmed in Xiangya Hospital, Central South University, China, and their clinical and image characteristics have been analyzed in order to provide reference for the prevention and early diagnosis of this disease. A total of 5 patients from one family, including 4 adults and 1 child, had a history of human contact in Wuhan, Hubei. Four adult patients showed different symptoms, including cough, fever, pharyngeal pain, and dyspnea, while the child patient had no symptoms. Laboratory examination showed no abnormality in all the patients except for slight increase in CRP in 2 patients and mild abnormal liver function index in 1 patient. The chest CT showed that all patients had abnormal images, with different degrees of manifestations.All patients were finally diagnosed by the nucleic acid test.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Adulto , COVID-19 , Niño , China , Infecciones por Coronavirus/epidemiología , Brotes de Enfermedades , Humanos , Neumonía Viral/epidemiología , SARS-CoV-2
9.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(3): 257-261, 2020 Mar 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32386016

RESUMEN

OBJECTIVES: To investigate the role of chest CT for the diagnostic work-up for patients with suspected infection of coronavirus disease 2019 (COVID-19). METHODS: The clinical data and imaging findings of the first nucleic acid-negative COVID-19 patients were analyzed and compared with the first nucleic acid-positive patients. RESULTS: Compared with the first nucleic acid-positive patients, the onset time of the first nucleic acid-negative patients was shorter [(3.58±2.94) d], but the diagnosis was longer [(3.92±3.66) d]. There were no significant differences in the characteristics of the clinical data and radiological findings between the 2 groups (P>0.05). CONCLUSION: Chest CT examination is important to avoid COVID-19 missed diagnosis due to false negative nucleic acid.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , COVID-19 , Humanos , Pandemias , SARS-CoV-2 , Tomografía Computarizada por Rayos X
10.
Mol Cell ; 42(1): 127-36, 2011 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-21474074

RESUMEN

Telomere-associated position-effect variegation (TPEV) in budding yeast has been used as a model for understanding epigenetic inheritance and gene silencing. A widely used assay to identify mutants with improper TPEV employs the URA3 gene at the telomere of chromosome VII-L that can be counterselected with 5-fluoroorotic acid (5-FOA). 5-FOA resistance has been inferred to represent lack of transcription of URA3 and therefore to represent heterochromatin-induced gene silencing. For two genes implicated in telomere silencing, POL30 and DOT1, we show that the URA3 telomere reporter assay does not reflect their role in heterochromatin formation. Rather, an imbalance in ribonucleotide reductase (RNR), which is induced by 5-FOA, and the specific promoter of URA3 fused to ADH4 at telomere VII-L are jointly responsible for the variegated phenotype. We conclude that metabolic changes caused by the drug employed and certain mutants being studied are incompatible with the use of certain prototrophic markers for TPEV.


Asunto(s)
Silenciador del Gen , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Telómero/genética , Telómero/metabolismo , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Efectos de la Posición Cromosómica , Genes Fúngicos , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Modelos Genéticos , Mutación , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ácido Orótico/análogos & derivados , Ácido Orótico/metabolismo , Antígeno Nuclear de Célula en Proliferación , Ribonucleótido Reductasas/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
11.
Nucleic Acids Res ; 45(W1): W501-W508, 2017 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-28482075

RESUMEN

Pathway analysis is widely used in omics studies. Pathway-based data integration and visualization is a critical component of the analysis. To address this need, we recently developed a novel R package called Pathview. Pathview maps, integrates and renders a large variety of biological data onto molecular pathway graphs. Here we developed the Pathview Web server, as to make pathway visualization and data integration accessible to all scientists, including those without the special computing skills or resources. Pathview Web features an intuitive graphical web interface and a user centered design. The server not only expands the core functions of Pathview, but also provides many useful features not available in the offline R package. Importantly, the server presents a comprehensive workflow for both regular and integrated pathway analysis of multiple omics data. In addition, the server also provides a RESTful API for programmatic access and conveniently integration in third-party software or workflows. Pathview Web is openly and freely accessible at https://pathview.uncc.edu/.


Asunto(s)
Programas Informáticos , Gráficos por Computador , Expresión Génica , Internet , Metabolómica , Interfaz Usuario-Computador
12.
Genes Dev ; 25(20): 2125-36, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21979375

RESUMEN

Cellular senescence acts as a potent barrier to tumorigenesis and contributes to the anti-tumor activity of certain chemotherapeutic agents. Senescent cells undergo a stable cell cycle arrest controlled by RB and p53 and, in addition, display a senescence-associated secretory phenotype (SASP) involving the production of factors that reinforce the senescence arrest, alter the microenvironment, and trigger immune surveillance of the senescent cells. Through a proteomics analysis of senescent chromatin, we identified the nuclear factor-κB (NF-κB) subunit p65 as a major transcription factor that accumulates on chromatin of senescent cells. We found that NF-κB acts as a master regulator of the SASP, influencing the expression of more genes than RB and p53 combined. In cultured fibroblasts, NF-κB suppression causes escape from immune recognition by natural killer (NK) cells and cooperates with p53 inactivation to bypass senescence. In a mouse lymphoma model, NF-κB inhibition bypasses treatment-induced senescence, producing drug resistance, early relapse, and reduced survival. Our results demonstrate that NF-κB controls both cell-autonomous and non-cell-autonomous aspects of the senescence program and identify a tumor-suppressive function of NF-κB that contributes to the outcome of cancer therapy.


Asunto(s)
Senescencia Celular/fisiología , Resistencia a Medicamentos/fisiología , Fenotipo , Factor de Transcripción ReIA/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/fisiología , Senescencia Celular/efectos de los fármacos , Senescencia Celular/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Linfoma/metabolismo , Ratones , Inhibidores de la Síntesis de la Proteína/farmacología , ARN Interferente Pequeño/metabolismo , Tetraciclina/farmacología , Proteína p53 Supresora de Tumor/metabolismo
13.
Genes Dev ; 25(15): 1628-40, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21828272

RESUMEN

Although human cancers have complex genotypes and are genomically unstable, they often remain dependent on the continued presence of single-driver mutations-a phenomenon dubbed "oncogene addiction." Such dependencies have been demonstrated in mouse models, where conditional expression systems have revealed that oncogenes able to initiate cancer are often required for tumor maintenance and progression, thus validating the pathways they control as therapeutic targets. Here, we implement an integrative approach that combines genetically defined mouse models, transcriptional profiling, and a novel inducible RNAi platform to characterize cellular programs that underlie addiction to MLL-AF9-a fusion oncoprotein involved in aggressive forms of acute myeloid leukemia (AML). We show that MLL-AF9 contributes to leukemia maintenance by enforcing a Myb-coordinated program of aberrant self-renewal involving genes linked to leukemia stem cell potential and poor prognosis in human AML. Accordingly, partial and transient Myb suppression precisely phenocopies MLL-AF9 withdrawal and eradicates aggressive AML in vivo without preventing normal myelopoiesis, indicating that strategies to inhibit Myb-dependent aberrant self-renewal programs hold promise as effective and cancer-specific therapeutics. Together, our results identify Myb as a critical mediator of oncogene addiction in AML, delineate relevant Myb target genes that are amenable to pharmacologic inhibition, and establish a general approach for dissecting oncogene addiction in vivo.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Leucemia/fisiopatología , Oncogenes/fisiología , Proteínas Proto-Oncogénicas c-myb/metabolismo , Animales , Modelos Animales de Enfermedad , Genes myb/genética , Hematopoyesis , Ratones , Proteínas de Fusión Oncogénica/metabolismo , Oncogenes/genética , Proteínas Proto-Oncogénicas c-myb/genética , Interferencia de ARN
14.
Glob Chang Biol ; 24(1): 184-196, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28727222

RESUMEN

The uncertainties of China's gross primary productivity (GPP) estimates by global data-oriented products and ecosystem models justify a development of high-resolution data-oriented GPP dataset over China. We applied a machine learning algorithm developing a new GPP dataset for China with 0.1° spatial resolution and monthly temporal frequency based on eddy flux measurements from 40 sites in China and surrounding countries, most of which have not been explored in previous global GPP datasets. According to our estimates, mean annual GPP over China is 6.62 ± 0.23 PgC/year during 1982-2015 with a clear gradient from southeast to northwest. The trend of GPP estimated by this study (0.020 ± 0.002 PgC/year2 from 1982 to 2015) is almost two times of that estimated by the previous global dataset. The GPP increment is widely spread with 60% area showing significant increasing trend (p < .05), except for Inner Mongolia. Most ecosystem models overestimated the GPP magnitudes but underestimated the temporal trend of GPP. The monsoon affected eastern China, in particular the area surrounding Qinling Mountain, seems having larger contribution to interannual variability (IAV) of China's GPP than the semiarid northwestern China and Tibetan Plateau. At country scale, temperature is the dominant climatic driver for IAV of GPP. The area where IAV of GPP dominated by temperature is about 42%, while precipitation and solar radiation dominate 31% and 27% respectively over semiarid area and cold-wet area. Such spatial pattern was generally consistent with global GPP dataset, except over the Tibetan Plateau and northeastern forests, but not captured by most ecosystem models, highlighting future research needs to improve the modeling of ecosystem response to climate variations.


Asunto(s)
Agricultura/tendencias , Cambio Climático , Ecosistema , China , Temperatura , Incertidumbre
15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 43(5): 505-510, 2018 May 28.
Artículo en Zh | MEDLINE | ID: mdl-29886466

RESUMEN

OBJECTIVE: To study the potential effects of intensity modulated radiation therapy (IMRT) on clinical efficacy, oral mucosa reaction and immunological foundation; and to explore the effect of immunological changes on clinical efficacy and oral mucosa reaction in patients with nasopharyngeal carcinoma.
 Methods: A total of 200 patients with nasopharyngeal carcinoma, who came from First Department of Nasopharyngeal Radiotherapy, the First People's Hospital of Foshan from October 2008 to November 2011, were selected. The patients were treated with nasopharyngeal radiotherapy, and divided into an observation group and a control group (n=100 in each group). The control group underwent common conventional two-dimensional radiotherapy treatment, while the observation group underwent IMRT. The 5-year survival rates and recurrence rates were recorded at follow-up. After the radiotherapy, the oral mucosa in the patients were evaluated by the classification standard of acute radioactive mucositis by American Radiotherapy Oncology Group (RTOG), and the number of T lymphocyte subsets before and after treatment was detected.
 Results: There were significant difference in non-regional-recurrence survival rate, disease-free survival rate, local recurrence rate between the above 2 groups (all P<0.05), but no significant difference in the distant metastasis-free survival rate (P>0.05). The acute oral mucosa reactions of grade 1, 2, 3, 4 in the control group were 8.00%, 20.00%, 12.00%, 7.00%, respectively, and those were 7.00%, 22.00%, 15.00%, 1.00% respectively. There was no significant difference in the acute response of oral mucosa in grade 1, 2 and 3 in the 2 groups (all P>0.05), but there was significant difference in the grade 4 (P<0.05). There were significantly difference in CD8+, CD4+/ CD8+ and CD4+ T lymphocyte subsets before and after treatment in the above 2 groups (all P<0.01); there were also significantly difference after treatment between the observation group and the control group (all P<0.01).
 Conclusion: In the process of treatment in patients with nasopharyngeal carcinoma, the use of IMRT on the basis of chemotherapy is more effective than the conventional two-dimensional radiotherapy, which can reduce the proportion of grade 4 (severe) acute oral mucosa reaction. It may be related to the protective effect of IMRT on immune function in the patients.


Asunto(s)
Carcinoma/radioterapia , Inmunidad/efectos de la radiación , Mucosa Bucal/efectos de la radiación , Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidad Modulada , Carcinoma/inmunología , Carcinoma/mortalidad , Supervivencia sin Enfermedad , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/inmunología , Neoplasias Nasofaríngeas/mortalidad , Estadificación de Neoplasias , Tasa de Supervivencia , Resultado del Tratamiento
16.
Nanotechnology ; 28(28): 285301, 2017 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-28574402

RESUMEN

We report uniform layer-by-layer sublimation of black phosphorus under heating below 600 K. The uniformity and crystallinity of BP samples after thermal thinning were confirmed by Raman spectra and Raman mapping. The sublimation rate of BP was around 0.18 nm min-1 at 500 K and 1.15 nm min-1 at 550 K. Both room and high temperature Raman peak intensity ratio [Formula: see text] as functions of BP thickness were established for in situ thickness determination and control. Uniform and crystalline 2 to 4-layer BP flakes with areas from 10 to 1000 µm2 were prepared with this method. No micron scale defects were observed. The sublimation thinning method was shown to be a controllable and scalable approach to prepare high-quality few-layer black phosphorus.

17.
Genes Dev ; 23(7): 877-89, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19339691

RESUMEN

The genetic heterogeneity of cancer influences the trajectory of tumor progression and may underlie clinical variation in therapy response. To model such heterogeneity, we produced genetically and pathologically accurate mouse models of common forms of human acute myeloid leukemia (AML) and developed methods to mimic standard induction chemotherapy and efficiently monitor therapy response. We see that murine AMLs harboring two common human AML genotypes show remarkably diverse responses to conventional therapy that mirror clinical experience. Specifically, murine leukemias expressing the AML1/ETO fusion oncoprotein, associated with a favorable prognosis in patients, show a dramatic response to induction chemotherapy owing to robust activation of the p53 tumor suppressor network. Conversely, murine leukemias expressing MLL fusion proteins, associated with a dismal prognosis in patients, are drug-resistant due to an attenuated p53 response. Our studies highlight the importance of genetic information in guiding the treatment of human AML, functionally establish the p53 network as a central determinant of chemotherapy response in AML, and demonstrate that genetically engineered mouse models of human cancer can accurately predict therapy response in patients.


Asunto(s)
Antineoplásicos/uso terapéutico , Modelos Animales de Enfermedad , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Ratones Endogámicos C57BL , Animales , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes ras/genética , Genes ras/fisiología , Genotipo , Humanos , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/fisiopatología , Ratones , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas de Fusión Oncogénica/genética , Pronóstico , Proteína 1 Compañera de Translocación de RUNX1 , Proteína p53 Supresora de Tumor/genética
18.
Proc Natl Acad Sci U S A ; 109(21): 8212-7, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22566646

RESUMEN

The large chromosomal deletions frequently observed in cancer genomes are often thought to arise as a "two-hit" mechanism in the process of tumor-suppressor gene (TSG) inactivation. Using a murine model system of hepatocellular carcinoma (HCC) and in vivo RNAi, we test an alternative hypothesis, that such deletions can arise from selective pressure to attenuate the activity of multiple genes. By targeting the mouse orthologs of genes frequently deleted on human 8p22 and adjacent regions, which are lost in approximately half of several other major epithelial cancers, we provide evidence suggesting that multiple genes on chromosome 8p can cooperatively inhibit tumorigenesis in mice, and that their cosuppression can synergistically promote tumor growth. In addition, in human HCC patients, the combined down-regulation of functionally validated 8p TSGs is associated with poor survival, in contrast to the down-regulation of any individual gene. Our data imply that large cancer-associated deletions can produce phenotypes distinct from those arising through loss of a single TSG, and as such should be considered and studied as distinct mutational events.


Asunto(s)
Carcinoma Hepatocelular/genética , Eliminación de Gen , Genes Supresores de Tumor/fisiología , Genómica/métodos , Neoplasias Hepáticas Experimentales/genética , Monosomía , Animales , Carcinoma Hepatocelular/mortalidad , Línea Celular Transformada , Línea Celular Tumoral , Cromosomas Humanos Par 8 , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Haploinsuficiencia/genética , Humanos , Hígado/citología , Neoplasias Hepáticas Experimentales/mortalidad , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Interferencia de ARN , Células Madre/citología
19.
Bioinformatics ; 29(14): 1830-1, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23740750

RESUMEN

SUMMARY: Pathview is a novel tool set for pathway-based data integration and visualization. It maps and renders user data on relevant pathway graphs. Users only need to supply their data and specify the target pathway. Pathview automatically downloads the pathway graph data, parses the data file, maps and integrates user data onto the pathway and renders pathway graphs with the mapped data. Although built as a stand-alone program, Pathview may seamlessly integrate with pathway and functional analysis tools for large-scale and fully automated analysis pipelines. AVAILABILITY: The package is freely available under the GPLv3 license through Bioconductor and R-Forge. It is available at http://bioconductor.org/packages/release/bioc/html/pathview.html and at http://Pathview.r-forge.r-project.org/. CONTACT: luo_weijun@yahoo.com SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Gráficos por Computador , Programas Informáticos , Expresión Génica , Redes y Vías Metabólicas , Transducción de Señal , Integración de Sistemas
20.
Sci Total Environ ; 915: 169967, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38211853

RESUMEN

Rapid CO2 degassing and calcite precipitation driven by cave ventilation influence the speleothem δ18O and δ13C. However, the drivers of cave ventilation are not completely understood due to the lack of monitoring of multiple environmental factors. Furthermore, the understanding of isotope fractionation caused by the dissolution of speleothem in undersaturated drip water is limited during the cave air stagnation. In this study, we displayed four years of cave microenvironment monitoring in Shawan Cave, Southwestern China, and analyzed the δ13CDIC and δ18O of drip water, and calcite precipitation δ18O and δ13C. The results show that the ventilation process is attributed to buoyancy airflow between external atmosphere, fissure air, and cave air. This causes that the higher (lower) cave air pCO2 in the summer (winter) is associated with upward airflow mode (downward airflow mode). Furthermore, cave ventilation could control the isotopic fractionation. Specifically, when cave air pCO2 is lower, the carbon isotopic disequilibrium between calcite and dissolved inorganic carbon (DIC) is controlled by the degassing of CO2 associated with calcite precipitation. The disequilibrium fractionation in carbon isotopes is less pronounced at slower drip-rate sites. The oxygen isotope fractionation between calcite and the drip water is found to be close to equilibrium. However, the high cave air pCO2 (exceeding 10,000 ppm) may result in drip water undersaturation to drive the dissolution of speleothem calcite. The δ18O values of drip water are pulled away from their original values to disequilibrate to the calcite because the exchange time of oxygen in the dissolved carbonates with the oxygen in the water is sufficiently long. Hence, the dissolution of speleothems may be a new mechanism to explain the oxygen isotopic disequilibrium between the calcite and drip water during the cave air stagnation. The carbon isotope fractionation between calcite and drip water is close to equilibrium.

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