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Wood formation consumes around 15% of the anthropogenic CO2 emissions per year and plays a critical role in long-term sequestration of carbon on Earth. However, the exogenous factors driving wood formation onset and the underlying cellular mechanisms are still poorly understood and quantified, and this hampers an effective assessment of terrestrial forest productivity and carbon budget under global warming. Here, we used an extensive collection of unique datasets of weekly xylem tissue formation (wood formation) from 21 coniferous species across the Northern Hemisphere (latitudes 23 to 67°N) to present a quantitative demonstration that the onset of wood formation in Northern Hemisphere conifers is primarily driven by photoperiod and mean annual temperature (MAT), and only secondarily by spring forcing, winter chilling, and moisture availability. Photoperiod interacts with MAT and plays the dominant role in regulating the onset of secondary meristem growth, contrary to its as-yet-unquantified role in affecting the springtime phenology of primary meristems. The unique relationships between exogenous factors and wood formation could help to predict how forest ecosystems respond and adapt to climate warming and could provide a better understanding of the feedback occurring between vegetation and climate that is mediated by phenology. Our study quantifies the role of major environmental drivers for incorporation into state-of-the-art Earth system models (ESMs), thereby providing an improved assessment of long-term and high-resolution observations of biogeochemical cycles across terrestrial biomes.
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Tracheophyta/crecimiento & desarrollo , Madera/crecimiento & desarrollo , Xilema/crecimiento & desarrollo , Clima , Cambio Climático , Ecosistema , Bosques , Calentamiento Global , Modelos Biológicos , Fotoperiodo , Estaciones del Año , Temperatura , Tracheophyta/genética , Árboles/crecimiento & desarrolloRESUMEN
BACKGROUND: The C-X-C chemokine receptor 4 (CXCR4) has been suggested to play an important role in several types of cancers and is related to biological behaviors connected with tumor progression. However, the clinical significance and application of CXCR4 in lung cancer remain disputable. Thus, we conducted a meta-analysis to investigate the impact of CXCR4 expression on survival and clinicopathological features in lung cancer. METHODS: Comprehensive literature searches were conducted in PubMed, Embase and Web of Science for relevant studies. We pooled hazard ratios (HRs)/odds ratios (ORs) with 95% confidence intervals (CIs) by STATA 12.0 to evaluate the potential value of CXCR4 expression. RESULTS: Twenty-seven relevant articles involving 2932 patients with lung cancer were included in our meta-analysis. The results revealed that CXCR4 expression was apparently associated with poor overall survival (OS) (HR 1.61, 95% CI 1.42-1.82) and disease-free survival (HR 3.39, 95% CI 2.38-4.83). Furthermore, a significant correlation with poor OS was obvious in non-small cell lung cancer patients (HR 1.59, 95% CI 1.40-1.81) and in patients showing CXCR4 expression in the cytoplasm (HR 2.10, 95% CI 1.55-2.84) and the membrane (HR 1.74, 95% CI 1.24-2.45). CXCR4 expression was significantly associated with men (OR 1.32, 95% CI 1.08-1.61), advanced tumor stages (T3-T4) (OR 2.34, 95% CI 1.28-4.28), advanced nodal stages (N > 0) (OR 2.34, 95% CI 1.90-2.90), distant metastasis (OR 3.65, 95% CI 1.53-8.69), advanced TNM stages (TNM stages III, IV) (OR 3.10, 95% CI 1.95-4.93) and epidermal growth factor receptor (EGFR) expression (OR 2.44, 95% CI 1.44-4.12) but was not associated with age, smoking history, histopathology, differentiation, lymphatic vessel invasion or local recurrence. CONCLUSION: High expression of CXCR4 is related to tumor progression and might be an adverse prognostic factor for lung cancer.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Humanos , Neoplasias Pulmonares/patología , Masculino , Estadificación de Neoplasias , Pronóstico , Receptores CXCR4/genética , Receptores CXCR4/metabolismoRESUMEN
BACKGROUND: Receptor for Advanced Glycation End-products (RAGE) is an oncogene abnormally expressed in various cancers. However, the clinical value of RAGE and the biological role of RAGE in lung cancer have not been fully investigated. METHODS: We compared the RAGE expression using several public databases. The relationship between RAGE expression and clinicopathological variables was assessed. The R software package was used to carry out enrichment analyses of RAGE co-expression and gene set enrichment analysis (GSEA). Additionally, we used the TIMER database to assess the association between immune infiltration and RAGE expression. The correlation between RAGE expression and senescence biomarkers in lung adenocarcinoma was analyzed using the TCGA database. RESULTS: Our findings indicated that the expression of RAGE was downregulated in lung adenocarcinoma, and down-regulation of RAGE was related to poor overall survival and disease-free survival. Functional enrichment analysis indicated that RAGE co-expression genes were mainly associated with neutrophil activation involved in immune response, neutrophil degranulation, and regulation of leukocyte-mediated immunity. Correlation analysis revealed that RAGE expression was closely related to the purity of the tumor and immune infiltration. GSEA indicated that the RAGE-related differential genes were mainly enriched in senescence-related pathways. Besides, the RAGE expression was significantly associated with senescence-related genes. CONCLUSION: Down-regulation of RAGE expression was associated with poor prognosis, as well as defective immune infiltration and cellular senescence in lung adenocarcinoma.
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Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Adenocarcinoma del Pulmón/patología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Senescencia Celular/genética , Humanos , Neoplasias Pulmonares/patología , Pronóstico , Receptor para Productos Finales de Glicación Avanzada/genética , Microambiente Tumoral/genéticaRESUMEN
Objective: Although the clinical application value of Aidi injection when treating non-small cell lung cancer (NSCLC) patients is explained only by the effectiveness of a certain literature or the improvement of a certain evaluation index, and the result is not convincing. To evaluate the effect of Aidi injection on life quality and incidence of adverse reactions in patients with NSCLCcompared with traditional chemotherapy. Methods: PubMed, EMBASE, ScienceDirect, Cochrane Library, China Journal full-text Database (CNKI), VIP full-text Database, Wanfang Database and Chinese Biomedical Literature data (CBM), search relevant Chinese and foreign periodicals, conference papers, degree papers, etc. were searched Database and China Biomedical Literature Database (CBM) to search case-control trials of Aidi injection when treating NSCLC patients. The retrieval period begins with the establishment of the database and ends when the database is closed. Cochrane Handbook 5.3 was adopted to assess the bias risk of each contained literature based on independently extracted data by two researchers. A meta-analysis of the collected data was carried out using RevMan5.3 statistical software. Results: 2306 articles were retrieved by computer database, 1422 articles were harvested by excluding repeated studies, 865 articles were harvested by preliminary reading of article titles and abstracts, and 533 articles were initially contained by excluding unrelated studies, reviews, case reports and uncontrolled articles, and then the full text of the literature was carefully read. Eight clinical controlled studies were finally included, with a total of 784 samples, after excluding 525 literatures with incomplete data and no primary outcome indicators. Data from the contained studies were not noticeably heterogeneous in the meta-analysis of treatment effectiveness. The fixed effect model analysis indicated that the treatment effective rate of the study group was noticeably better, and the difference was statistically significant(P<0.05). The findings of the heterogeneity test were clearly heterogeneous among the contained research data, according to the meta-analysis of the levels of T lymphocyte subsets following treatment. The random effect model analysis indicated that the improvement of the cellular immune function of the research group was obvious, and the difference was statistically significant (P<0.05). According to the meta-analysis of the life quality scores after treatment, data from the contained research were evidently heterogeneous, according to results of the heterogeneity test. The random effect model analysis indicated that the life quality of the study group was noticeably higher, and the difference was statistically significant (P<0.05). The levels of serum vascular endothelial growth factor (VEGF) after treatment were measured by meta. Data from the contained research were evidently heterogeneous, according to results of the heterogeneity test. Random effect model analysis indicated that the level of serum VEGF in the study group was noticeably lower, and the difference was not statistically significant (P>0.05). A meta-analysis was conducted on the incidence of adverse reactions after treatment. The results of the heterogeneity test indicated that data from the contained research were evidently heterogeneous. The incidence was noticeably lower, and the difference was statistically significant (P<0.05). The funnel chart was drawn based on the effective rate of treatment, the level of T lymphocyte subsets, the score of life quality, the level of serum VEGF and the incidence of adverse reactions, and the publication bias analysis was carried out. The results indicated that most of the funnel maps were symmetrical and a small part of them were asymmetrical, suggesting that despite the heterogeneity of the study and the small number of included literatures, a publication bias was apparent in the included literature. Conclusion: Based on routine chemotherapy associated with Aidi injection, the therapeutic effect of NSCLC patients can be noticeably enhanced, the effective rate of treatment can be noticeably promoted, the immune function and life quality can be improved, and the incidence of adverse reactions is low, which is worth popularizing in clinical practice, but several studies and follow-ups are needed to improve methodological quality and to verify the results over a longer period of time.
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BACKGROUND: The prevalence of obstructive sleep apnea (OSA) in older people (aged over 65 years) is high. However, OSA in older populations has not received sufficient attention. This study examined the clinical phenotypic characteristics of older patients with newly diagnosed OSA. METHODS: A total of 110 older patients (≥ 65 years) and 220 younger patients (< 65 years), matched by gender, body mass index (BMI), and apnea-hypopnea index (AHI), were enrolled in this retrospective study. Clinical manifestations, comorbidities, and polysomnographic results were compared between the two groups, and correlations between age ≥ 65 years and OSA comorbidities were explored. RESULTS: Nocturia was more common in older patients with OSA, as with lower sleep efficiency, longer wake after sleep onset, increased stage N1 sleep, and decreased stage N3 sleep and average SpO2. The proportions of older OSA patients who had comorbid hypertension, coronary artery disease (CAD), chronic obstructive pulmonary disease, and ischemic stroke were significantly higher than those of younger patients. The incidence of tonsillar enlargement and pharyngeal narrowing was lower in older patients. Age ≥ 65 years was an independent risk factor for patients with OSA to have hypertension (OR: 1.89, 95% CI: 1.11-3.21), CAD (OR: 4.83, 95% CI: 2.29-10.21), and ischemic stroke (OR: 2.92, 95% CI: 1.02 to 8.38). CONCLUSIONS: The presence of OSA in older adults was associated with significant abnormalities of sleep architecture, aggravated nocturnal hypoxia and increased risks of hypertension, CAD, and stroke, which can be distinguished as a unique clinical phenotype.
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Enfermedad de la Arteria Coronaria , Hipertensión , Accidente Cerebrovascular Isquémico , Apnea Obstructiva del Sueño , Humanos , Anciano , Estudios Retrospectivos , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/complicaciones , Enfermedad de la Arteria Coronaria/complicaciones , Fenotipo , HospitalesRESUMEN
The connections between the primary and secondary growth of trees allows better understanding of the dynamics of carbon sequestration in forest ecosystems. The relationship between primary and secondary growth of trees could change due to the diverging responses of meristems to climate warming. In this study, the bud phenology and radial growth dynamics of Qinghai spruce (Picea crassifolia) in arid and semi-arid areas of China in 2019 and 2020 were weekly monitored to analyze their response to different weather conditions and their links with carbon sink. Xylem anatomical traits (i.e. lumen radial diameter and cell wall thickness) were quantified along cell radial files after the end of xylem lignification to calculate the early-to-latewood transition date. Winter and early spring (January-March) were warmer in 2020 with a colder April compared with 2019. Precipitation in April-June was lower in 2020 than in 2019. In 2019, bud phenology occurred earlier, while the onset of xylem formation and the early-to-latewood transition date were delayed. The duration from the beginning of split bud and exposed shoot to the early-to-latewood transition date was positively correlated with the radial width of earlywood (accounting for ~80% of xylem width) and total xylem width. The longer duration of xylem cell division did not increase xylem cell production and radial width. Moreover, the duration from bud burst to the early-to-latewood transition date in 2020 was negatively linked with early phloem cell production as compared with 2019. Our findings suggest that warm conditions in winter and early spring promote the xylogenesis of Qinghai spruce, but might delay bud burst. However, the xylem width increments largely depend on the duration from bud burst to the start of latewood cell division rather than on the earlier xylogenesis and longer duration of xylem cell differentiation induced by warm conditions.
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Picea , Madera , Ecosistema , Xilema , Clima , Estaciones del Año , ÁrbolesRESUMEN
p53-induced ring-H2 protein (PIRH2), a newly identified E3 ubiquitin ligase, has been reported to be interacted with p27Kip1 and promote ubiquitination of p27Kip1 independently of p53. p27kip1, a member of the Cip/Kip family of cyclin-dependent kinases inhibitors (CKIs), was shown to control cell cycle progression and promote cell proliferation. While the distribution and function of PIRH2 and p27kip1 in nervous system lesion and regeneration remains unclear. Here, we performed a sciatic nerve injury model in adult rats and studied the dynamic changes of PIRH2 and p27kip1 expression by western blot and RT-PCR in injured rat sciatic nerve. Sciatic nerve crush resulted in a significant up-regulation of PIRH2 and a down-regulation of p27kip1. Besides, we observed that they were expressed widely in both Schwann cells and axons in adult rat sciatic nerve by double immunofluorescence staining. Results obtained by coimmunoprecipitation and double labeling further showed their interaction in the regenerating process. Thus, these results indicate that PIRH2 and p27kip1 likely play an important role in peripheral nerve injury and regeneration.
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Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas de Choque Térmico/metabolismo , Proteínas Nucleares/metabolismo , Neuropatía Ciática/metabolismo , Neuropatía Ciática/fisiopatología , Análisis de Varianza , Animales , Proteínas Reguladoras de la Apoptosis , Proliferación Celular , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Modelos Animales de Enfermedad , Proteínas de Choque Térmico/genética , Inmunoprecipitación , Antígeno Ki-67/metabolismo , Masculino , Regeneración Nerviosa/fisiología , Proteínas de Neurofilamentos/metabolismo , Proteínas Nucleares/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Proteínas S100/metabolismo , Células de Schwann/patología , Nervio Ciático/metabolismo , Neuropatía Ciática/patología , Factores de TiempoRESUMEN
Atmospheric nitrogen (N) deposition and increasing precipitation affect carbon sequestration in terrestrial ecosystems, but how these two concurrent global change variables affect xylem growth in trees (i.e., independently or interactively) remains unclear. We conducted novel experiments in central China to monitor the xylem growth in a dominant species (Quercus acutissima Caruth.) in response to N addition (CN), supplemental precipitation (CW) or both treatments (CNW), compared with untreated controls (C). Measurements were made at weekly intervals during 2014-15. We found that supplemental precipitation significantly enhanced xylem growth in the dry spring of 2015, indicating a time-varying effect of increased precipitation on intra-annual xylem growth. Elevated N had no significant effect on xylem increment, xylem growth rate, and lumen diameters and potential hydraulic conductivity (Ks) of earlywood vessels, but Ks with elevated N was significantly negatively related to xylem increment. The combination of additional N and supplemental precipitation suppressed the positive effect of supplemental precipitation on xylem increment in the dry spring of 2015. These findings indicated that xylem width was more responsive to supplemental precipitation than to increasing N in a dry early growing season; the positive effect of supplemental precipitation on xylem growth could be offset by elevated N resources. The negative interactive effect of N addition and supplemental precipitation also suggested that increasing N deposition and precipitation in the future might potentially affect carbon sequestration of Q. acutissima during the early growing season in central China. The effects of N addition and supplemental precipitation on tree growth are complex and might vary depending on the growth period and local climatic conditions. Therefore, future models of tree growth need to consider multiple-time scales and local climatic conditions when simulating and projecting global change.
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Quercus , Ecosistema , Nitrógeno , Quercus/fisiología , Árboles , Xilema/fisiologíaRESUMEN
INTRODUCTION: Current pandemic of the coronavirus induced disease 2019 (COVID-19) presents an urgent issue to the world due to lack of vaccine and medication. Hydroxychloroquine (HCQ) has generated a lot of controversies whether it is effective in prevention and treatment of COVID-19. Current report presents a 63-year-old woman who has taken HCQ for many years but still infected by COVID-19. CASE PRESENTATION: A patient with rheumatoid arthritis came to the clinic with fever and sore throat. The patient has been treated with 200 mg HCQ per day since 2016. Laboratory tests showed that the patient had lymphopenia, increased levels of high-sensitive C-reactive protein (hs-CRP) and serum Interleukin-6 (IL-6). Chest radiography showed that the patient had pneumonia. Throat swab test confirmed COVID-19 positive. On admission, she was treated with nebulized interferon alfa-2b, oral Lopinavir/Ritonavir, and ceftriaxone sodium for the COVID-19 in addition to HCQ. The patient stayed in hospital for 18 days, recovered from oxygen intake, and eventually discharged from hospital. Follow up investigation showed the patient developed antibody against COVID-19. CONCLUSIONS: Long-term application of HCQ could not prevent COVID-19 infection, but whether HCQ exerts benefit to alleviation of clinical symptoms and duration of hospital stays remains to be further investigated.
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Antivirales/administración & dosificación , Tratamiento Farmacológico de COVID-19 , COVID-19/prevención & control , Hidroxicloroquina/administración & dosificación , Antivirales/uso terapéutico , COVID-19/diagnóstico por imagen , Femenino , Humanos , Interferón alfa-2/uso terapéutico , Persona de Mediana Edad , Radiografía , SARS-CoV-2/efectos de los fármacos , Factores de Tiempo , Resultado del TratamientoRESUMEN
Background: The occurrence and severity of excessive daytime sleepiness (EDS) vary considerably among obstructive sleep apnea (OSA) patients. This study was designed to investigate the characteristics of EDS and identify its contributing factors in OSA patients. Methods: This was a cross-sectional study from a tertiary medical center in China. A total of 874 consecutive patients with newly diagnosed OSA were included. Subjective daytime sleepiness was assessed with the Epworth Sleepiness Scale (ESS). The subjects were assigned to the non-EDS group (582 patients), mild to moderate EDS group (227 patients), and severe EDS group (65 patients) according to the ESS scores. The clinical features and polysomnographic parameters were acquired and analyzed to identify the differences between groups and the determinants of EDS. Results: The age of patients with severe EDS (49.5 ± 11.3) was slightly greater than that of patients with mild to moderate EDS (44.5 ± 10.2) (p < 0.05) and non-EDS patients (45.2 ± 12.0) (p < 0.05). Body mass index (BMI) was highest in the severe EDS group (29.1 ± 3.6 kg/m2) (p < 0.0001), intermediate in the mild to moderate EDS group (27.9 ± 3.3 kg/m2), and lower in the non-EDS group (26.8 ± 3.3 kg/m2). Logistic regression analysis showed waist circumference, memory loss, work/commute disturbances, and sleep efficiency were independently associated with mild to moderate EDS, and the microarousal index, apnea-hypopnea index (AHI), and saturation impair time below 90% were independent contributing factors of mild to moderate EDS. Meanwhile, age, neck circumference, gasping/choking, memory loss, work/commute disturbances, and sleep latency were independently associated with severe EDS, and the AHI and mean SpO2 were independent contributing factors of severe EDS. Conclusions: OSA patients with various severities of EDS are more obese and have more comorbid symptoms compared to patients without EDS. Sleep fragmentation, respiratory events, and nocturnal hypoxia may be predictors of EDS. Comprehensive consideration of demographic, clinical, and polysomnographic factors is required when evaluating OSA patients.
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Apnea Obstructiva del Sueño/fisiopatología , Somnolencia , Adulto , China/epidemiología , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Estudios Prospectivos , Apnea Obstructiva del Sueño/epidemiologíaRESUMEN
China's subtropical forests play a vital role in sequestering global carbon; therefore, it is critical to conduct a precise investigation of intra-annual wood formation in these ecosystems to clarify the mechanisms behind this. Two field experiments were established in Chinese subtropical forests to monitor weekly the intra-annual xylem formation of Pinus massoniana Lamb. from January to December 2015, using the recently developed micro-sampling approach. The effects of climate on wood formation were also assessed using linear or mixed models. Results indicate that there is an inactive period that might be semi-dormancy in subtropical pine ecosystems in January compared with the complete dormancy in temperate and boreal ecosystems and the fully active or short-term dormancy in tropical ecosystems. The duration of xylem formation of Chinese red pine in subtropical China in 2015 was 4-6 months longer than temperate and boreal forests. Moreover, trees were found to grow better during the dry season than the wet season, indicating that the Chinese red pine ecosystem is more strongly regulated by net energy than by environmental factors. Our findings indicate that China's subtropical pine forests may benefit from the expected longer dry seasons, possibly leading to better forest growth and improved carbon sequestration under continued climate warming.
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Pinus/crecimiento & desarrollo , Madera/crecimiento & desarrollo , Cámbium/crecimiento & desarrollo , China , Lluvia , Estaciones del Año , Xilema/crecimiento & desarrolloRESUMEN
Increasing N deposition caused by intensive anthropogenic activities is expected to affect forest growth. However, the effects of N deposition on trees are still controversial due to the wide variability in results and experimental methods used. We conducted an experiment involving both canopy and understory N addition to investigate the effects of N-addition on intra-annual xylem formation of Chinese sweetgum (Liquidambar formosana) in a warm-temperate forest of Central China. Since 2013, 50 kg N ha-1 year-1 (2.5 times the current natural N deposition) was applied monthly from April to December. In 2014 and 2015, the timing and dynamics of xylem formation were monitored weekly during March-December by microcoring the stems of control and treated trees. Similar dynamics of wood formation were observed between canopy and understory N addition. Xylem formation of all the experimental trees started in March and lasted for 119-292 days. Compared to the control, no change was observed in the timing and dynamics of wood formation in N-treated trees. Tree ring-width ranged between 1701 and 4774 µm, with a rate of xylem production of 10.52-26.64 µm day-1. The radial growth of trees was not modified by the treatments. Our findings suggest that short-term N addition is unable to affect the dynamics of xylem formation in Chinese sweetgum in Central China. The effects of N on tree growth observed in previous studies might be related to the duration of the experiment or the imbalance between the amount of natural deposition and N added during treatments.
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BACKGROUND: Chronic obstructive pulmonary disease (COPD) is often accompanied by acute exacerbations. Patients of COPD exacerbation suffering from respiratory failure often need the support of mechanical ventilation. Helium-oxygen can be used to reduce airway resistance during mechanical ventilation. The aim of this study is to evaluate the effect of helium-oxygen-assisted mechanical ventilation on COPD exacerbation through a meta-analysis. METHODS: A comprehensive literature search through databases of Pub Med (1966â¼2016), Ovid MEDLINE (1965â¼2016), Cochrane EBM (1991â¼2016), EMBASE (1974â¼2016) and Ovid MEDLINE was performed to identify associated studies. Randomized clinical trials met our inclusion criteria that focus on helium-oxygen-assisted mechanical ventilation on COPD exacerbation were included. The quality of the papers was evaluated after inclusion and information was extracted for meta-analysis. RESULTS: Six articles and 392 patients were included in total. Meta-analysis revealed that helium-oxygen-assisted mechanical ventilation reduced Borg dyspnea scale and increased arterial PH compared with air-oxygen. No statistically significant difference was observed between helium-oxygen and air-oxygen as regards to WOB, PaCO2 , OI, tracheal intubation rates and mortality within hospital. CONCLUSIONS: Our study suggests helium-oxygen-assisted mechanical ventilation can help to reduce Borg dyspnea scale. In terms of the tiny change of PH, its clinical benefit is negligible. There is no conclusive evidence indicating the beneficial effect of helium-oxygen-assisted mechanical ventilation on clinical outcomes or prognosis of COPD exacerbation.
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Helio/farmacología , Oxígeno/farmacología , Respiración con Presión Positiva/métodos , Enfermedad Pulmonar Obstructiva Crónica/terapia , Insuficiencia Respiratoria/etiología , Humanos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Recurrencia , Insuficiencia Respiratoria/terapiaRESUMEN
In recent decades, anthropogenic activities have increased nitrogen (N) deposition in terrestrial ecosystems. This higher availability of N is expected to impact plant growth. However, the effects of N deposition on tree growth remain inconclusive due to the wide variability of experimental methods used. This study aimed to test the effect of short-term N addition on the intra-annual wood formation of Chinese red pine (Pinus massoniana Lamb.) in a warm-temperate forest of Central China. From 2013, solution containing 25 kg N ha-1 year-1 was applied monthly to the understory of experimental plots from April to December to double the current natural N deposition. Each week from March to December in 2014 and 2015, cambial activity and the timings and dynamics of xylem formation were monitored by collecting microcores from stems. Xylem formation lasted from March to November, producing an average of 19 and 33 cells for all studied trees in 2014 and 2015, respectively. No difference in xylem cell production was observed between control and N-treated trees. Moreover, N-treated trees had similar timings, rates and durations of xylem formation as control trees. These findings indicated that short-term N addition was unable to affect timings and dynamics of xylem formation in Chinese red pine of warm-temperate forest.
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Nitrógeno/metabolismo , Pinus/crecimiento & desarrollo , Madera/crecimiento & desarrollo , China , Estaciones del Año , Xilema/crecimiento & desarrolloRESUMEN
Obstructive sleep apnea (OSA) associated chronic kidney disease is mainly caused by chronic intermittent hypoxia (CIH) triggered tissue damage. Receptor for advanced glycation end product (RAGE) and its ligand high mobility group box 1 (HMGB1) are expressed on renal cells and mediate inflammatory responses in OSA-related diseases. To determine their roles in CIH-induced renal injury, soluble RAGE (sRAGE), the RAGE neutralizing antibody, was intravenously administered in a CIH model. We also evaluated the effect of sRAGE on inflammation and apoptosis. Rats were divided into four groups: (1) normal air (NA), (2) CIH, (3) CIH+sRAGE, and (4) NA+sRAGE. Our results showed that CIH accelerated renal histological injury and upregulated RAGE-HMGB1 levels involving inflammatory (NF-κB, TNF-α, and IL-6), apoptotic (Bcl-2/Bax), and mitogen-activated protein kinases (phosphorylation of P38, ERK, and JNK) signal transduction pathways, which were abolished by sRAGE but p-ERK. Furthermore, sRAGE ameliorated renal dysfunction by attenuating tubular endothelial apoptosis determined by immunofluorescence staining of CD31 and TUNEL. These findings suggested that RAGE-HMGB1 activated chronic inflammatory transduction cascades that contributed to the pathogenesis of the CIH-induced renal injury. Inhibition of RAGE ligand interaction by sRAGE provided a therapeutic potential for CIH-induced renal injury, inflammation, and apoptosis through P38 and JNK pathways.
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BACKGROUND AND OBJECTIVES: While an increasing number of people who snore are seeking medical consultations, the clinical characteristics of snorers are rarely reported. The aim of this study is to characterize the clinical and polysomnographic features in a population of snorers. METHODS: A total of 490 subjects were examined retrospectively. The clinical history, Epworth Sleepiness Scale (ESS) scores, physical examination, and full-night polysomnography (PSG) data were obtained for all the subjects. The correlations between the neck circumference, waist circumference, ESS scores, body mass index (BMI), and apnea-hypopnea index (AHI) of obstructive sleep apnea (OSA) patients were explored. The gender and age differences in OSA patients were analyzed. RESULTS: OSA was diagnosed in 84.7% of the sample, with 21.2% of the patients having a mild form, 15.4% having a moderate form, and 63.4% having a severe form of OSA. The ESS scores, neck circumference, waist circumference, and BMI were positively correlated with AHI in OSA patients. The ESS scores and BMI were negatively correlated with nadir oxygen saturation (SaO2). A greater number of men than women exhibited moderate to severe forms of the disease. OSA affects the work of males more commonly compared with females. Nocturia was a more common complaint in elderly OSA patients. Heart diseases coexisted more frequently with OSA in elderly patients. CONCLUSIONS: In a population of snorers, OSA is the most common condition identified. The ESS scores and BMI were well correlated with the severity of the disease. Men had a more severe form of OSA than women. Nocturia frequently occurred in elderly OSA patients, as did the coexistence of heart disease.
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Polisomnografía , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/fisiopatología , Ronquido/fisiopatología , Adulto , Factores de Edad , Anciano , Pueblo Asiatico , Índice de Masa Corporal , China/epidemiología , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuello/patología , Factores de Riesgo , Factores Sexuales , Apnea Obstructiva del Sueño/epidemiología , Circunferencia de la CinturaRESUMEN
The aboveground architecture, biomass and its allocation, and the relationship between architecture and biomass of Quercus variabilis of different diameter classes in Shangluo, south slope of Qinling Mountains were researched. The results showed that differences existed in the aboveground architecture and biomass allocation of Q. variabilis of different diameter classes. With the increase of diameter class, tree height, DBH, and crown width increased gradually. The average decline rate of each diameter class increased firstly then decreased. Q. variabilis overall bifurcation ratio and stepwise bifurcation ratio increased then declined. The specific leaf areas of Q. variabilis of all different diameter classes at vertical direction were 0.02-0.03, and the larger values of leaf mass ratio, LAI and leaf area ratio at vertical direction in diameter level I , II, III appeared in the middle and upper trunk, while in diameter level IV, V, VI, they appeared in the central trunk, with the increase of diameter class, there appeared two peaks in vertical direction, which located in the lower and upper trunk. The trunk biomass accounted for 71.8%-88.4% of Q. variabilis aboveground biomass, while the branch biomass accounted for 5.8%-19.6%, and the leaf biomass accounted for 4.2%-8.6%. With the increase of diameter class, stem biomass proportion of Q. variabilis decreased firstly then increased, while the branch and leaf biomass proportion showed a trend that increased at first then decreased, and then increased again. The aboveground biomass of Q. variabilis was significantly positively correlated to tree height, DBH, crown width and stepwise bifurcation ratio (R2:1), and positively related to the overall bifurcation ratio and stepwise bifurcation ratio (R3:2), but there was no significant correlation. Trunk biomass and total biomass aboveground were negatively related to the trunk decline rate, while branch biomass and leaf biomass were positively related to trunk decline rate, but their correlations were all not significant.
Asunto(s)
Biomasa , Quercus/crecimiento & desarrollo , Hojas de la Planta/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrollo , Árboles/crecimiento & desarrolloRESUMEN
Typical sampling method was conducted to survey the effects of forest gap size on branch architecture, leaf characteristics and their vertical distribution of Quercus variablis seedlings from different size gaps in natural secondary Q. variablis thinning forest, on the south slope of Qinling Mountains. The results showed that gap size significantly affected the diameter, crown area of Q. variablis seedlings. The gap size positively correlated with diameter and negatively correlated with crown area, while it had no significant impact on seedling height, crown length and crown rates. The overall bifurcation ratio, stepwise bifurcation ratio, and ratio of branch diameter followed as large gap > middle gap > small gap > understory. The vertical distribution of first-order branches under different size gaps mainly concentrated at the middle and upper part of trunk, larger diameter first-order branches were mainly distributed at the lower part of trunk, and the angle of first-order branch increased at first and then declined with the increasing seedling height. With the increasing forest gap size, the leaf length, leaf width and average leaf area of seedlings all gradually declined, while the average leaf number per plant and relative total leaf number increased, the leaf length-width ratio kept stable, the relative leaf number was mainly distributed at the middle and upper parts of trunk, the changes of leaf area index was consistent with the change of the relative total number of leaves. There was no significant difference between the diameters of middle gap and large gap seedlings, but the diameter of middle gap seedlings was higher than that of large gap, suggesting the middle gap would benefit the seedlings regeneration and high-quality timber cultivation. To promote the regeneration of Q. variabilis seedlings, and to cultivate high-quality timber, appropriate thinning should be taken to increase the number of middle gaps in the management of Q. variabilis forest.