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1.
Phytochem Anal ; 35(2): 409-418, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37872850

RESUMEN

INTRODUCTION: Panax ginseng and Panax quinquefolium are traditional Chinese herb medicines and similar in morphology and some chemical components but differ in drug properties, so they cannot be mixed. However, the processed products of them are often sold in the form of slices, powder, and capsules, which are difficult to identify by traditional morphological methods. Furthermore, an accurate evaluation of P. ginseng, P. quinquefolium and the processed products have not been conducted. OBJECTIVE: This study aimed to establish a catalysed hairpin assembly (CHA) identification method for authenticating products made from P. ginseng and P. quinquefolium based on single nucleotide polymorphism (SNP) differences. METHOD: By analysing the differences of SNP in internal transcribed spacer 2 (ITS2) in P. ginseng and P. quinquefolium to design CHA-specific hairpins. Establish a sensitive and efficient CHA method that can identify P. ginseng and P. quinquefolium, use the sequencing technology to verify the accuracy of this method in identifying Panax products, and compare this method with high-resolution melting (HRM). RESULTS: The reaction conditions of CHA were as follows: the ratio of forward and reverse primers, 20:1; hairpin concentration, 5 ng/µL. Compared with capillary electrophoresis, this method had good specificity and the limit of detection was 0.5 ng/µL. The result of Panax product identification with CHA method were coincidence with that of the sequencing method; the positive rate of CHA reaction was 100%. CONCLUSION: This research presents an effective identification method for authenticating P. ginseng and P. quinquefolium products, which is helpful to improve the quality of Panax products.


Asunto(s)
Panax , Panax/genética , Panax/química , Medicina Tradicional China , Polimorfismo de Nucleótido Simple , Tecnología
2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 68-71, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38433634

RESUMEN

Terminally ill patients face multiple difficulties in home care.Home-based palliative care adhering to the concept of whole-person,whole-family,whole-team,and whole-course care is able to meet the needs of terminally ill patients and their families.In this paper,we reported the care history and home-based palliative care process of a patient with end-stage breast tumor and summarized the experience,aiming to provide reference for the future work of home-based palliative care.


Asunto(s)
Cuidados Paliativos , Humanos
3.
Ecotoxicol Environ Saf ; 251: 114519, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36634478

RESUMEN

Blue light with a wavelength of 400-470 nm is the composition of the visible light. However, in recent years, blue light contributed the most significance to light pollution due to the artificial light at night. Previously, we have demonstrated that the Asian citrus psyllid (ACP), Diaphorina citri, an important pest in citrus production, has significant positive phototaxis with a light-emitting diode light of 400 nm. In this study, ACP with positive phototactic behavior to 400 nm light (PH) and non-phototactic behavior to 400 nm light (NP) were collected, individually. Transcriptome dynamics of head tissues of PH and NP groups were captured by using RNA-sequencing technology, respectively. Forty-three to 46 million clean reads with high-quality values were obtained, and 1773 differential expressed genes (DEGs) were detected. Compared with the NP group, there were 841 up-regulated DEGs and 932 down-regulated DEGs in the PH group. Eight pathways were significantly enriched in the PH group in the KEGG database, while 43 up-regulated pathways and 25 down-regulated pathways were significantly enriched in the PH group in the GO database. The DGE approach was reliable validated by real time quantitative PCR. Results indicated that the blue light acted as an abiotic stress causing physiological and biochemical responses such as oxidative stress, protein denaturation, inflammation and tumor development in ACPs. Additionally, the light was absorbed by photoreceptors of ACPs, and converted into electrical signal to regulate neuromodulation. This study provides basic information for understanding the molecular mechanisms of ACP in response to blue light and provides a reference for further studies to elucidate phototactic behavior.


Asunto(s)
Citrus , Hemípteros , Animales , Fototaxis , Hemípteros/genética , Hemípteros/metabolismo , Transcriptoma , Luz , Citrus/genética , Encéfalo
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(5): 746-749, 2022 Oct.
Artículo en Zh | MEDLINE | ID: mdl-36325768

RESUMEN

Community-based home hospice care provided by community service centers and family physician teams aims to alleviate the suffering of terminally ill patients and help them to receive end-of-life care and pass away at home.The Puhuangyu Community Health Service Center established the home hospice care model of PUMCH-Puhuangyu Coordination at the end of 2019.The model has been practiced and improved to date.This paper introduces this model of home hospice care.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Cuidados Paliativos al Final de la Vida , Hospitales para Enfermos Terminales , Cuidado Terminal , Humanos , Centros de Atención Terciaria
5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(5): 757-762, 2022 Oct.
Artículo en Zh | MEDLINE | ID: mdl-36325770

RESUMEN

Objective To investigate the feasibility of home hospice care based on the practical experience in Puhuangyu community of Beijing.Methods We selected the patients assessed by hospice care team and receiving home hospice care from Puhuangyu Community Health Service Center of Beijing from January 1,2020 to December 31,2021.The clinical manifestations,hospice services received,and place of death of the patients were analyzed. Results A total of 24 patients were included in this study.They mainly suffered from malignant tumors(18 patients,75.0%),with pain as the most common symptom(12 patients,50.0%).The patients received a variety of hospice services through a combination of outpatient visits,home visits,and WeChat follow-up.The service time of each patient was(2.8±1.7) h each week on average and 57.9%(11/19) of the patients passed away at home. Conclusions The home hospice care in Puhuangyu community has a stable source of patients.The members of this hospice team can provide a variety of home hospice services.With this model,the wish to pass away at home can be achievable for most patients.Therefore,this model of community-based home hospice care is feasible.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Cuidados Paliativos al Final de la Vida , Hospitales para Enfermos Terminales , Humanos , Beijing
6.
Respir Res ; 21(1): 201, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32727465

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a new respiratory and systemic disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The purpose of the present study was to investigate the association between cytokine profiles and lung injury in COVID-19 pneumonia. METHODS: This retrospective study was conducted in COVID-19 patients. Demographic characteristics, symptoms, signs, underlying diseases, and laboratory data were collected. The patients were divided into COVID-19 with pneumonia and without pneumonia. CT severity score and PaO2/FiO2 ratio were used to assess lung injury. RESULTS: 106 patients with 12 COVID-19 without pneumonia and 94 COVID-19 with pneumonia were included. Compared with COVID-19 without pneumonia, COVID-19 with pneumonia had significantly higher serum interleukin (IL)-2R, IL-6, and tumor necrosis factor (TNF)-α. Correlation analysis showed that CT severity score and PaO2/FiO2 were significantly correlated with age, presence of any coexisting disorder, lymphocyte count, procalcitonin, IL-2R, and IL-6. In multivariate analysis, log IL6 was the only independent explanatory variables for CT severity score (ß = 0.397, p < 0.001) and PaO2/FiO2 (ß = - 0.434, p = 0.003). CONCLUSIONS: Elevation of circulating cytokines was significantly associated with presence of pneumonia in COVID-19 and the severity of lung injury in COVID-19 pneumonia. Circulating IL-6 independently predicted the severity of lung injury in COVID-19 pneumonia.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/complicaciones , Citocinas/sangre , Lesión Pulmonar/etiología , Neumonía Viral/complicaciones , Adulto , Biomarcadores/sangre , COVID-19 , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/epidemiología , Femenino , Humanos , Lesión Pulmonar/sangre , Lesión Pulmonar/diagnóstico , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Estudios Retrospectivos , SARS-CoV-2 , Tomografía Computarizada por Rayos X
7.
Inorg Chem ; 58(16): 10694-10703, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31390195

RESUMEN

The reactions of chiral ligand (R)/(S)-1,1'-binaphthyl-2,2'-diyl phosphate (R-HL/S-HL) and ErCl3·6H2O afford two pairs of di- and tetranuclear enantiomers [Er2(R/S-L)4(EtOH)6]Cl2·6.5EtOH (R-1, S-1) and [Er4(PO4)(R/S-L)8(EtOH)3(H2O)]2Cl(OH)·15EtOH·11H2O (R-2, S-2). The nuclearity of these complexes is controllable and depends on the reaction temperature with a template effect. Their chirality was evidenced by circular dichroism (CD) spectra. R-1 exhibits two magnetic relaxation pathways under a zero field, with an apparent barrier of 40 K. Ab initio calculations revealed a ferromagnetic dipolar interaction between these two Er(III) ions, the equatorial nature of the ligand field, and the probable origin of the two relaxations.

8.
Molecules ; 24(16)2019 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-31408943

RESUMEN

A multi-residue method for the determination of 107 pesticide residues in wolfberry has been developed and validated. Similar pretreatment approaches were compared, and the linearity, matrix effect, analysis limits, precision, stability and accuracy were validated, which verifies the satisfactory performance of this new method. The LODs and LOQs were in the range of 0.14-1.91 µg/kg and 0.46-6.37 µg/kg, respectively. The recovery of analytes at three fortification levels (10 µg/kg, 50 µg/kg, 100 µg/kg) ranged from 63.3-123.0%, 72.0-118.6% and 67.0-118.3%, respectively, with relative standard deviations (RSDs) below 15.0%. The proposed method was applied to the analysis of fifty wolfberry samples collected from supermarkets, pharmacies and farmers' markets in different cities of Shandong Province. One hundred percent of the samples analyzed included at least one pesticide, and a total of 26 pesticide residues was detected in fifty samples, which mainly were insecticides and bactericide. Several pesticides with higher detection rates were 96% for acetamiprid, 82% for imidacloprid, 54% for thiophanate-methyl, 50% for blasticidin-S, 42% for carbendazim, 42% for tebuconazole and 36% for difenoconazole in wolfberry samples. This study proved the adaptability of the developed method to the detection of multiple pesticide residues in wolfberry and provided basis for the research on the risks to wolfberry health.


Asunto(s)
Extracción Líquido-Líquido/métodos , Lycium/química , Residuos de Plaguicidas/aislamiento & purificación , Bencimidazoles/aislamiento & purificación , Carbamatos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Humanos , Neonicotinoides/aislamiento & purificación , Nitrocompuestos/aislamiento & purificación , Nucleósidos/aislamiento & purificación , Residuos de Plaguicidas/clasificación , Espectrometría de Masas en Tándem/métodos , Tiofanato/aislamiento & purificación , Triazoles/aislamiento & purificación
9.
Yi Chuan ; 37(7): 621-34, 2015 07.
Artículo en Zh | MEDLINE | ID: mdl-26351162

RESUMEN

Post-translational modifications (PTMs) are essential for regulating conformational changes, activities and functions of proteins, and are involved in almost all cellular pathways and processes. Identification of protein PTMs is the basis for understanding cellular and molecular mechanisms. In contrast with labor-intensive and time-consuming experiments, the PTM prediction using various bioinformatics approaches can provide accurate, convenient, and efficient strategies and generate valuable information for further experimental consideration. In this review, we summarize the current progresses made by Chineses bioinformaticians in the field of PTM Bioinformatics, including the design and improvement of computational algorithms for predicting PTM substrates and sites, design and maintenance of online and offline tools, establishment of PTM-related databases and resources, and bioinformatics analysis of PTM proteomics data. Through comparing similar studies in China and other countries, we demonstrate both advantages and limitations of current PTM bioinformatics as well as perspectives for future studies in China.


Asunto(s)
Biología Computacional , Procesamiento Proteico-Postraduccional , China , Humanos
10.
Proc Natl Acad Sci U S A ; 108(20): 8345-50, 2011 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-21531904

RESUMEN

Pseudogenes have been shown to acquire unique regulatory roles from more and more organisms. We report the observation of a cluster of siRNAs derived from pseudogenes of African Trypanosoma brucei using high through-put analysis. We show that these pseudogene-derived siRNAs suppress gene expression through RNA interference. The discovery that siRNAs may originate from pseudogenes and regulate gene expression in a unicellular eukaryote provides insights into the functional roles of pseudogenes and into the origin of noncoding small RNAs.


Asunto(s)
Regulación de la Expresión Génica/genética , Seudogenes/genética , ARN Interferente Pequeño/genética , Trypanosoma brucei brucei/genética , Genes Protozoarios
11.
ScientificWorldJournal ; 2014: 457937, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25054180

RESUMEN

The effects of two levels of irrigation water (100%, 60%) and buried underground pipe depths (0.8 m, 0.6 m) under rain shelters' conditions on yield and some quality parameters of tomato were investigated. A fully randomized factorial experiment was conducted between April and August in 2011 and 2012 at Hohai University. It was found that drainage treatments enhanced biomass production, whereas soil desiccation led to biomass reduction. At 60 cm buried underground pipe depths, the drought treatments increased the mean root weight and root-shoot ratio by 14% and 39%, respectively. The main effects of drainage treatments on the fruit quality were increases in total soluble solids (TSS), soluble sugar (SS), and vitamin C (VC) compared to the control. In addition, drainage treatments increased the average yield by 13% and 9%, respectively, in both years. The drought treatments did not significantly alter fruit yield, although mean single fruit weight was slightly reduced. Instead, these treatments tend to have great potential to improve fruit quality (TSS, SS, and VC) to variable extents. In both years, the drought treatment at 60 cm buried underground pipe depths proved to possess the highest comprehensive quality index based on Principal Component Analysis.


Asunto(s)
Riego Agrícola/métodos , Solanum lycopersicum/crecimiento & desarrollo , Ácido Ascórbico/análisis , Carbohidratos/análisis , Solanum lycopersicum/química , Solanum lycopersicum/normas , Valor Nutritivo
12.
Sci China Life Sci ; 67(1): 67-82, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37864083

RESUMEN

Chronic pain often develops severe mood changes such as depression. However, how chronic pain leads to depression remains elusive and the mechanisms determining individuals' responses to depression are largely unexplored. Here we found that depression-like behaviors could only be observed in 67.9% of mice with chronic neuropathic pain, leaving 32.1% of mice with depression resilience. We determined that the spike discharges of the ventral tegmental area (VTA)-projecting lateral habenula (LHb) glutamatergic (Glu) neurons were sequentially increased in sham, resilient and susceptible mice, which consequently inhibited VTA dopaminergic (DA) neurons through a LHbGlu-VTAGABA-VTADA circuit. Furthermore, the LHbGlu-VTADA excitatory inputs were dampened via GABAB receptors in a pre-synaptic manner. Regulation of LHb-VTA pathway largely affected the development of depressive symptoms caused by chronic pain. Our study thus identifies a pivotal role of the LHb-VTA pathway in coupling chronic pain with depression and highlights the activity-dependent contribution of LHbGlu-to-VTADA inhibition in depressive behavioral regulation.


Asunto(s)
Dolor Crónico , Habénula , Ratones , Animales , Área Tegmental Ventral/metabolismo , Habénula/metabolismo , Depresión , Ácido gamma-Aminobutírico/metabolismo
13.
J Nat Prod ; 76(10): 1896-901, 2013 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-24099304

RESUMEN

Six new 4-phenyl-3,4-dihydroquinolone derivatives (1-6) along with the related aflaquinolone A (7) were isolated and identified from the cultures of Aspergillus nidulans MA-143, an endophytic fungus obtained from the fresh leaves of the marine mangrove plant Rhizophora stylosa. Their structures including absolute configurations were determined by spectroscopic analysis and electronic circular dichroism experiments, and the structure of compound 1 was confirmed by single-crystal X-ray crystallographic analysis. In bioscreening experiments, none of the isolated compounds showed potent antibacterial or cytotoxic activity. However, compounds 2, 3, and 7 exhibited lethality against brine shrimp (Artemia salina), with LD50 values of 7.1, 4.5, and 5.5 µM, respectively.


Asunto(s)
Aspergillus nidulans/química , Quinolonas/aislamiento & purificación , Rhizophoraceae/microbiología , Animales , Artemia/efectos de los fármacos , Dicroismo Circular , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/efectos de los fármacos , Femenino , Células HL-60 , Humanos , Células K562 , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/microbiología , Quinolonas/química , Quinolonas/farmacología , Staphylococcus aureus/efectos de los fármacos
14.
Mar Drugs ; 11(6): 2230-8, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23792827

RESUMEN

Two new secondary metabolites, namely, pinodiketopiperazine A (1) and 6,7-dihydroxy-3-methoxy-3-methylphthalide (2), along with alternariol 2,4-dimethyl ether (3) and L-5-oxoproline methyl ester (4), which were isolated from a natural source for the first time but have been previously synthesized, were characterized from the marine sediment-derived fungus Penicillium pinophilum SD-272. In addition, six known metabolites (5-10) were also identified. Their structures were elucidated by analysis of the NMR and mass spectroscopic data. The absolute configuration of compound 1 was determined by experimental and calculated ECD spectra. Compound 2 displayed potent brine shrimp (Artemia salina) lethality with LD50 11.2 µM.


Asunto(s)
Antibacterianos/farmacología , Sedimentos Geológicos/microbiología , Penicillium/metabolismo , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Artemia/efectos de los fármacos , Dosificación Letal Mediana , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Toxicidad/métodos
15.
Mar Drugs ; 11(7): 2682-94, 2013 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-23880937

RESUMEN

Four new quinazolinone alkaloids, namely, aniquinazolines A-D (1-4), were isolated and identified from the culture of Aspergillus nidulans MA-143, an endophytic fungus obtained from the leaves of marine mangrove plant Rhizophora stylosa. The structures of the new compounds were elucidated by spectroscopic analysis, and their absolute configurations were determined on the basis of chiral HPLC analysis of the acidic hydrolysates. The structure for 1 was confirmed by single-crystal X-ray diffraction analysis. All these compounds were examined for antibacterial and cytotoxic activity as well as brine shrimp (Artemia salina) lethality.


Asunto(s)
Alcaloides/química , Alcaloides/farmacología , Aspergillus nidulans/química , Quinazolinonas/química , Quinazolinonas/farmacología , Animales , Antibacterianos/química , Antibacterianos/farmacología , Artemia/efectos de los fármacos , Factores Biológicos/química , Factores Biológicos/farmacología , Cristalografía por Rayos X/métodos , Estructura Molecular , Hojas de la Planta/química , Rhizophoraceae/microbiología , Difracción de Rayos X/métodos
16.
Acta Crystallogr C ; 69(Pt 2): 138-41, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23377678

RESUMEN

The title compound, [Co(C(10)H(8)N(2))(3)](2)[V(4)O(12)]·11H(2)O, is composed of two symmetry-related cations containing octahedrally coordinated Co(II) ions, a centrosymmetric [V(4)O(12)](4-) anion with an eight-membered ring structure made up of four VO(4) tetrahedra, and 11 solvent water molecules. The Co(II) cations and vanadate anions are isolated and build cation and anion layers, respectively. In addition, the title compound exhibits a three-dimensional network through intra- and intermolecular hydrogen-bond interactions between water molecules and O atoms of the anions, and the crystal structure is stabilized mainly by hydrogen bonds.

17.
Yi Chuan ; 34(7): 872-8, 2012 Jul.
Artículo en Zh | MEDLINE | ID: mdl-22805213

RESUMEN

In order to gain more extensive insight into detailed genetic control mechanisms of porcine meat quality and mine novel candidate genes, this study focused on the relationship between the genes of propanpate metabolism pathway and porcine meat quality as well as carcass traits based on the candidate gene set approach. Thirty-seven DLY pigs were tested in this study. A total of 36 SNPs within 7 candidate genes of propanoate metabolism pathway were genotyped and association analysis was conducted via Least Squares method, Multivariate multiple regression model, and a model-based multifactor dimensionality reduction method (MB-MDR). As a result, four SNPs in genes PCCB, MUT, MCEE, and ACSS1 were significantly associated with DLY pig meat quality or carcass traits (P<0.05). Results of MB-MDR analysis demonstrated that the interactions between multiple SNPs were significantly associated with the backfat thickness, water content, and fat content (P<0.05). ACSS2 was significantly associated with fat content; MCEE and MUT significantly influenced backfat thickness; and PCCB was related to fat weight. Moreover, the interactions between the genes in the propanoate metabolism pathway had remarkable influence in porcine meat quality and carcass traits.


Asunto(s)
Productos de la Carne/normas , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Propionatos/metabolismo , Sitios de Carácter Cuantitativo , Animales , Femenino , Frecuencia de los Genes , Ligamiento Genético , Genotipo , Masculino , Redes y Vías Metabólicas/genética , Porcinos
18.
Zhong Yao Cai ; 35(10): 1557-61, 2012 Oct.
Artículo en Zh | MEDLINE | ID: mdl-23627117

RESUMEN

OBJECTIVE: To explore the relation between the quality of the Herb-Paris and their cultivation of soil nutritional status. METHODS: The soil nutrient status (0 - 30 cm) of Paris polyphylla var. yunnanensis, artificially cultivated areas were determined in 2009 and their rhizome qualities harvested in 2010 were evaluated respectively. Determination of 0 - 30cm depth soil ingredients status with soil conventional five nutritional analysis method of 29 artificial cultivation area, 9 Prefectures of Yunnan Province. RESULTS: Soil nutrient has effect on quality of Herb-Paris medicinal ingredients. CONCLUSION: The multiple linear stepwise regression analysis reveals that among a certain range, the steroidal saponin VII content is positively correlated with the content of soil organic matter and pH. Steroidal saponin H content is positively correlated with the content of soil organic matter, available P and pH. Steroidal saponin I is positively correlated with the content of available K, but negatively correlated with the content of available Herb-Paris, and steroidal saponin II is positively correlated with the content of soil organic matter and available K.


Asunto(s)
Liliaceae/química , Nitrógeno , Rizoma/química , Saponinas/análisis , Suelo/análisis , Agricultura/métodos , China , Cromatografía Líquida de Alta Presión , Fertilizantes , Concentración de Iones de Hidrógeno , Liliaceae/crecimiento & desarrollo , Fósforo , Potasio , Control de Calidad , Análisis de Regresión , Rizoma/crecimiento & desarrollo , Suelo/química
19.
Ying Yong Sheng Tai Xue Bao ; 33(12): 3287-3293, 2022 Dec.
Artículo en Zh | MEDLINE | ID: mdl-36601833

RESUMEN

To investigate the variation of soil water holding capacity under different land use types can provide scientific basis for evaluating the change characteristics and regulation mechanism of water conservation capacity in alpine ecosystems. We collected soil samples at different depth intervals (0-10, 10-20 and 20-30 cm) under three land use types (farmland, forest, and grassland) in Tibet alpine region to measure the maximum water holding capacity, capillary water holding capacity, field capacity, and basic soil physicochemical properties. The associated environmental factors (mean annual precipitation, normalized difference vegetation index, altitude, slope gradient and surface roughness) were extracted to analyze the change characteristics and influencing factors of soil water holding capacity under different land use types. The results showed that soil water holding capacity (the maximum water holding capacity, capillary water holding capacity, and field capacity) of farmland, forest, and grassland all decreased with increasing soil depth. The mean values of the maximum water holding capacity, capillary water holding capacity, and field capacity in the 0-30 cm soil layer of grassland were 379.79, 329.57 and 194.39 g·kg-1, respectively, which were significantly higher than that of farmland (301.15, 259.67, and 154.91 g·kg-1) and forest (293.09, 251.49, and 117.01 g·kg-1). Results of the redundancy analysis showed that soil properties significantly influenced soil water holding capacity, with explanation rate of 44.6%, 42.7%, 37.6% and 35.8% for total porosity, soil organic matter, capillary porosity and soil bulk density, respectively. Results of the principal component analysis showed that mean annual precipitation, normalized difference vegetation index, altitude, slope gradient, and surface roughness were the main environmental factors affecting the spatial variation of soil water holding capacity, with a cumulative contribution of 72.4%. The grassland in the alpine region of Tibet had the highest water holding capacity and could effectively prevent soil erosion. Therefore, the implementation of returning farmland to grassland and the enclosure management of degraded grassland would be conducive to improve soil water conservation capacity in the alpine regions.


Asunto(s)
Ecosistema , Suelo , Tibet , Suelo/química , Agua , Región Alpina Europea , China , Pradera
20.
J Affect Disord ; 298(Pt A): 357-363, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34774645

RESUMEN

BACKGROUND: Suicide has become a severe public health issue worldwide. Body weight has been put forward as a potentially modifiable element for suicide thought and behavior. However, there are discrepancies across previous studies. Furthermore, the relationships of body weight with suicidal ideation and suicide attempt among low- and middle-income countries (LMICs) remain unclear. Therefore, we addressed this issue among 104,907 adolescents of 12-15 years old in 45 LMICs. METHODS: The present study used data from the Global School-based Student Health Survey (GSHS). Suicidal ideation and suicide attempt during the last year were self-reported. Participants were classified intro underweight, normal weight, overweight and obesity according to their body mass index classification. Multivariable logistic regression and meta-analyses based on country-wise estimates were conducted. RESULTS: The prevalence of suicidal ideation and suicide attempt were 11.8% and 13.0%, respectively. Countrywide meta-analysis demonstrated that overweight and obesity were significantly associated with increased risks of suicidal ideation (For overweight: OR = 1.10; 95% CI = 1.01-1.20; for obesity: OR=1.17; 95%CI: 1.01-1.35) and suicide attempt (For overweight: OR = 1.12; 95% CI = 1.02-1.23; for obesity: OR=1.12; 95%CI: 1.00-1.25). Subgroup analyses showed that the associations between overweight/obesity and suicide attempt were significant for girls but not for boys. LIMITATIONS: The cross-sectional design cannot explore causality; mental health factors were not assessed; suicidal behaviors were self-reported; significant heterogeneity across countries; only students attending school were included. CONCLUSIONS: Overweight/obesity was significantly associated with the risk of suicidal ideation and suicide attempt among adolescents in LMICs.


Asunto(s)
Países en Desarrollo , Ideación Suicida , Adolescente , Índice de Masa Corporal , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Factores de Riesgo , Intento de Suicidio
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