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1.
BMC Plant Biol ; 23(1): 257, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37189097

RESUMEN

BACKGROUND: Wild apple (Malus sieversii) is under second-class national protection in China and one of the lineal ancestors of cultivated apples worldwide. In recent decades, the natural habitation area of wild apple trees has been seriously declining, resulting in a lack of saplings and difficulty in population regeneration. Artificial near-natural breeding is crucial for protecting and restoring wild apple populations, and adding nitrogen (N) and phosphorous (P) is one of the important measures to improve the growth performance of saplings. In this study, field experiments using N (CK, N1, N2, and N3: 0, 10, 20, and 40 g m- 2 yr- 1, respectively), P (CK, P1, P2, and P3: 0, 2, 4, and 8 g m- 2 yr- 1, respectively), N20Px (CK, N2P1, N2P2, and N2P3: N20P2, N20P4 and N20P8 g m- 2 yr- 1, respectively), and NxP4 (CK, N1P2, N2P2, and N3P2: N10P4, N20P4, and N40P4 g m- 2 yr- 1, respectively) treatments (totaling 12 levels, including one CK) were conducted in four consecutive years. The twig traits (including four current-year stem, 10 leaf, and three ratio traits) and comprehensive growth performance of wild apple saplings were analyzed under different nutrient treatments. RESULTS: N addition had a significantly positive effect on stem length, basal diameter, leaf area, and leaf dry mass, whereas P addition had a significantly positive effect on stem length and basal diameter only. The combination of N and P (NxP4 and N20Px) treatments evidently promoted stem growth at moderate concentrations; however, the N20Px treatment showed a markedly negative effect at low concentrations and a positive effect at moderate and high concentrations. The ratio traits (leaf intensity, leaf area ratio, and leaf to stem mass ratio) decreased with the increase in nutrient concentration under each treatment. In the plant trait network, basal diameter, stem mass, and twig mass were tightly connected to other traits after nutrient treatments, indicating that stem traits play an important role in twig growth. The membership function revealed that the greatest comprehensive growth performance of saplings was achieved after N addition alone, followed by that under the NxP4 treatment (except for N40P4). CONCLUSIONS: Consequently, artificial nutrient treatments for four years significantly but differentially altered the growth status of wild apple saplings, and the use of appropriate N fertilizer promoted sapling growth. These results can provide scientific basis for the conservation and management of wild apple populations.


Asunto(s)
Malus , Malus/genética , Fitomejoramiento , Nitrógeno , Hojas de la Planta , Fenotipo
2.
J Plant Res ; 135(1): 55-67, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34762207

RESUMEN

Ephemeral plants are a crucial vegetation component in temperate deserts of Central Asia, and play an important role in biogeochemical cycle and biodiversity maintenance in desert ecosystems. However, the nitrogen (N) and phosphorus (P) status and interrelations of leaf-root-soil of ephemeral plants remain unclear. A total of 194 leaf-root-soil samples of eight ephemeral species at 37 sites in the Gurbantunggut Desert, China were collected, and then the corresponding N and P concentrations, and the N:P ratio were measured. Results showed that soil parameters presented no significant difference among the eight species. The total soil N:P was only 0.116 (geomean), indicating limited soil N, while the available soil N:P (4.896, geomean) was significantly larger than the total N:P. The leaf N (averagely 30.995 mg g-1) and P (averagely 1.523 mg g-1) concentrations were 2.64-8.46 and 0.93-3.99 times higher than the root N (averagely 8.014 mg g-1) and P (averagely 0.802 mg g-1) concentrations, respectively. Thus, leaf N:P (averagely 21.499) was 1.410-2.957 times higher than root N:P (averagely 11.803). Meanwhile, significant interspecific differences existed in plant stoichiometric traits. At the across-species level, N content scaled as the 3/4-power of P content in both leaves and roots. Leaf and root N:P ratios were mainly influenced by P; however, the leaf-to-root N or P ratio was dominated by roots. Leaf and root N, P contents and N:P were generally unrelated to soil nutrients, and the former presented lower variation than the latter, indicating a strong stoichiometric homeostasis for ephemerals. These results demonstrate that regardless of soil nutrient supply capacity in this region, the fast-growing ephemeral plants have formed a specific leaf-root-soil stoichiometric relation and nutrient use strategy adapting to the extreme desert environment.


Asunto(s)
Ecosistema , Suelo , China , Nitrógeno/análisis , Fósforo , Hojas de la Planta/química , Plantas
3.
J Huazhong Univ Sci Technolog Med Sci ; 34(4): 575-581, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25135730

RESUMEN

Obstructive nephropathy ultimately leads to end-stage renal failure. Renovascular lesions are involved in various nephropathies, and most renal diseases have an ischemic component that underlies the resulting renal fibrosis. The aim of this study was to investigate whether morphological changes occur in the renal vasculature in hydronephrosis and the possible mechanisms involved. A model of complete unilateral ureteral obstruction (CUUO) was used. Experimental animals were divided into five groups: a normal control group (N) and groups of animals at 1st week (O1), 2nd week (O2), 4th week (O4) and 8th week (O8) after CUUO. Blood pressure was measured, renal arterial trees and glomeruli were assessed quantitatively, and renovascular three-dimensional reconstruction was performed on all groups. Glomerular ultrastructural changes were examined by transmission electron microscopy. The results showed that the systolic blood pressure was significantly increased in the obstructed groups (O1, O2, O4 and O8). Three-dimensional reconstruction showed sparse arterial trees in the O8 group, and a tortuous and sometimes ruptured glomerular basement membrane was found in the O4 and O8 groups. Furthermore, epithelial media thickness and media/lumen ratio were increased, lumen diameters were decreased, and the cross-sectional area of the media was unaltered in the segmental renal artery, interlobar artery and afferent arterioles, respectively. In conclusion, renal arterial trees and glomeruli were dramatically altered following CUUO and the changes may be partially ascribed to vascular remodeling. Elucidation of the molecular mechanisms of renovascular morphological alterations will enable the development of potential therapeutic approaches for hydronephrosis.


Asunto(s)
Presión Sanguínea , Membrana Basal Glomerular , Hidronefrosis , Animales , Modelos Animales de Enfermedad , Membrana Basal Glomerular/irrigación sanguínea , Membrana Basal Glomerular/patología , Membrana Basal Glomerular/fisiopatología , Hidronefrosis/patología , Hidronefrosis/fisiopatología , Masculino , Conejos , Arteria Renal/patología , Arteria Renal/fisiopatología
4.
Front Plant Sci ; 14: 1099110, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36890885

RESUMEN

Background: Considerable attention has been given to how different aspects of biodiversity sustain ecosystem functions. Herbs are a critical component of the plant community of dryland ecosystems, but the importance of different life form groups of herbs is often overlooked in experiments on biodiversity-ecosystem multifunctionality. Hence, little is known about how the multiple attributes of diversity of different life form groups of herbs affect changes to the multifunctionality of ecosystems. Methods: We investigated geographic patterns of herb diversity and ecosystem multifunctionality along a precipitation gradient of 2100 km in Northwest China, and assessed the taxonomic, phylogenetic and functional attributes of different life form groups of herbs on the multifunctionality. Results: We found that subordinate (richness effect) species of annual herbs and dominant (mass ratio effect) species of perennial herbs were crucial for driving multifunctionality. Most importantly, the multiple attributes (taxonomic, phylogenetic and functional) of herb diversity enhanced the multifunctionality. The functional diversity of herbs provided greater explanatory power than did taxonomic and phylogenetic diversity. In addition, the multiple attribute diversity of perennial herbs contributed more than annual herbs to multifunctionality. Conclusions: Our findings provide insights into previously neglected mechanisms by which the diversity of different life form groups of herbs affect ecosystem multifunctionality. These results provide a comprehensive understanding of the relationship between biodiversity and multifunctionality, and will ultimately contribute to multifunctional conservation and restoration programs in dryland ecosystems.

5.
Plants (Basel) ; 12(18)2023 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-37765450

RESUMEN

International interest is growing in biodiversity conservation and sustainable use in drylands. Desert ecosystems across arid Central Asia are severely affected by global change. Understanding the changes in a plant community is an essential prerequisite to revealing the community assembly mechanism, vegetation conservation, and management. The knowledge of large-scale spatial variation in plant community structure in different Central Asian deserts is still limited. In this study, we selected the Taukum (TD, Kazakhstan) and the Gurbantunggut (GD, China) deserts as the research area, with similar latitudes despite being nearly 1000 km apart. Thirteen and 15 sampling plots were set up and thoroughly investigated. The differences in community structure depending on multiple plant attributes (individual level: plant height, canopy diameter, and plant volume, and community level: plant density, total cover, and total volume) were systematically studied. TD had a better overall environmental status than GD. A total of 113 species were found, with 68 and 74 in TD and GD, respectively. The number of species and plant attributes was unequally distributed across different families and functional groups between deserts. The values of several plant attributes, such as ephemerals, annuals, dicotyledons, and shrubs with assimilative branches in GD, were significantly lower than those in TD. The Motyka indices of six plant attributes (26.18-38.61%) were higher between the two deserts than the species similarity index (20.4%), indicating a more robust convergence for plant functional attributes. The community structures in the two deserts represented by different plant attribute matrices demonstrated irregular differentiation patterns in ordination diagrams. The most variance in community structure was attributed to soil and climatic factors, while geographic factors had the smallest proportion. Consequently, the community structures of the two distant deserts were both different and similar to an extent. This resulted from the long-term impacts of heterogeneous environments within the same region. Our knowledge is further deepened by understanding the variation in community structure in different deserts on a large spatial scale. This therefore provides valuable insights into conserving regional biodiversity in Central Asia.

6.
Front Plant Sci ; 13: 1064504, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36582643

RESUMEN

Shrubs play a major role in maintaining ecosystem stability in the arid deserts of Central Asia. During the long-term adaptation to extreme arid environments, shrubs have developed special assimilative branches that replace leaves for photosynthesis. In this study, four dominant shrubs with assimilative branches, namely Haloxylon ammodendron, Haloxylon persicum, Calligonum mongolicum, and Ephedra przewalskii, were selected as the research objects, and the dry mass, total length, node number, and basal diameter of their assimilative branches and the average length of the first three nodes were carefully measured, and the allometric relationships among five traits of four species were systematically compared. The results indicated that: (1) Four desert shrubs have different assimilative branches traits. Compared with H. persicum and H. ammodendron, C. mongolicum and E. przewalskii have longer internodes and fewer nodes. The dry mass of H. ammodendron and the basal diameter of H. persicum were the smallest; (2) Significant allometric scaling relationships were found between dry mass, total length, basal diameter, and each trait of assimilative branches, all of which were significantly less than 1; (3) The scaling exponents of the allometric relationship between four traits and the dry mass of assimilative branches of H. persicum were greater or significantly greater than those of H. ammodendron. The scaling exponents of the relationships between the basal diameter, dry mass, and total length of E. przewalskii were higher than those of the other three shrubs. Therefore, although different species have adapted to drought and high temperatures by convergence, there was great variability in morphological characteristics of assimilative branches, as well as in the scaling exponents of relationships among traits. The results of this study will provide valuable insights into the ecological functions of assimilative branches and survival strategies of these shrubs to cope with aridity and drought in desert environments.

7.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3340-3348, 2020 Oct.
Artículo en Zh | MEDLINE | ID: mdl-33314823

RESUMEN

To reveal mechanisms underlying the dieback of Malus sieversii in degraded wild fruit forest in Ili valley of China, we compared the differences in stem hydraulic architecture, water transport effectiveness and safety, as well as their influencing factors among three growth classes of dead branches ratios, including Class Ⅰ (<20%), Class Ⅱ (40%-60%) and Class Ⅲ (>80%), respectively. With the increases in degradation degree of Xinjiang wild fruit forest, sapwood-specific hydraulic conductivity and leaf-specific hydraulic conductivity decreased, without significant differences among the three growth classes. Branch embolism at dusk and hydraulic safety significantly increased. The xylem water potential at 50% loss of hydraulic conductivity was -1.87, -1.35 and -0.53 MPa for Class Ⅰ, Ⅱ and Ⅲ, respectively. Predawn and midday leaf water potential and the hydraulic safety margin exhibited an order of Ⅰ>Ⅱ>Ⅲ. Xylem anatomical cha-racteristics and branch and leaf traits related to hydraulics were significantly different among the three growth classes. Results from correlation analysis revealed a weak tradeoff between xylem-specific hydraulic efficiency and xylem safety of M. sieversii. Stem hydraulic architecture of M. sieversii altered with the decline of Xinjiang wild apple forest. With increasing degrees of degradation, the severity of xylem embolisms aggravated, resistance to cavitation embolisms reduced, and the risk of water imbalance increased.


Asunto(s)
Malus , China , Bosques , Frutas , Hojas de la Planta , Tallos de la Planta , Árboles , Agua , Xilema
8.
Neurol Res ; 42(1): 8-16, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31878844

RESUMEN

Objectives: Long noncoding RNAs (lncRNAs) play substantial roles in cerebral ischemia. Growth arrest-specific 5 (GAS5) was reported to be involved in stroke. In the present study, we aimed to investigate the roles of GAS5 in cerebral condition and unveil the underlying mechanism.Method: Transient focal ischemia was induced by intraluminal occlusion of the right Middle cerebral artery occlusion (MCAO) and 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to evaluate the volume of cerebral infarction. RT-qPCR was applied to evaluate the level of GAS5 and miR-221. Fluorescence activated Cell Sorting (FACS) and Terminal deoxynucleotidyl transferased (TUNEL)  were used for detection of apoptosis. Western blotting was applied for protein level. Luciferase assay was applied to reveal the underlying relationship between GAS5 and miR-221 or p53-upregulated modulator of apoptosis (PUMA) and miR-221.Results: The results indicated that GAS5 was up-regulated in MCAO rats and in vitro hypoxia cell model while miR-221 expression was decreased in vitro hypoxia cell model. GAS5 promoted cells apoptosis, while miR-221 inhibited cell apoptosis through regulation of PUMA and downstream JNK/H2AX signaling. Moreover, GAS5 and miR-221 have direct interaction and PUMA was the target of miR-221, indicating that GAS5 regulated PUMA through sponging miR-221.Conclusions: the present study revealed that GAS5 aggravated cell apoptosis in hypoxia condition via miR-221/PUMA axis, which may provide potential targets for the treatment of stroke.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/biosíntesis , Apoptosis/fisiología , Isquemia Encefálica/metabolismo , MicroARNs/metabolismo , Neuronas/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Isquemia Encefálica/patología , Hipoxia de la Célula/fisiología , Células Cultivadas , Células HEK293 , Humanos , Masculino , Neuronas/patología , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba/fisiología
9.
Chin J Integr Med ; 25(6): 446-453, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26016454

RESUMEN

OBJECTIVE: To investigate the hepatoprotective effect of Xijiao Dihuang Decoction (, XJDHD) on lipopolysaccharide (LPS)- and tumor necrosis factor alpha (TNF-α)-induced acute liver failure (ALF) as well as the underlying mechanism of action, and to clarify the key herbs and components of XJDHD. METHODS: LPS/D-galactosamine (D-GalN) or TNF-α/D-GalN were intraperitoneally injected into C57BL/6J mice to induce ALF. Simultaneously, XJDHD or its individual herbs and components were orally administered. Survival rates, transaminase levels in serum, and hepatic histology were examined to evaluate the effects of XJDHD. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and real-time polymerase chain reaction were additionally performed to expound the mechanism underlying the anti-apoptotic activity of XJDHD. RESULTS: Oral administration of XJDHD protected mice from lethal liver failure induced by LPS and TNF-α, with notable amelioration of liver injury in histology and a significant decrease in transaminase levels in serum. XJDHD significantly inhibited apoptosis of hepatocytes and enhanced expression of the antiapoptosis genes, c-Flip, Iap1, Gadd45b and A20. In addition, Rehmannia glutinosa Libosch. was identified as the key herb of XJDHD and galactose as the effective component of Rehmannia glutinosa Libosch. that protects against ALF. CONCLUSIONS: XJDHD inhibits TNF-α-induced apoptosis of hepatocytes by promoting the expression of nuclear factor κ B-regulated anti-apoptotic genes. Rehmannia glutinosa Libosch. is the effective herb of XJDHD and galactose is an active component in this protection.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/tratamiento farmacológico , Sustancias Protectoras/uso terapéutico , Rehmannia/química , Animales , Apoptosis/efectos de los fármacos , Citocinas/biosíntesis , Galactosamina , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Lipopolisacáridos , Fallo Hepático Agudo/patología , Masculino , Ratones Endogámicos C57BL , Factor de Necrosis Tumoral alfa
11.
Ann Anat ; 210: 76-83, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27986617

RESUMEN

OBJECTIVE: We investigated and compared the functionality of two 3D visualization software provided by a CT vendor and a third-party vendor, respectively. Using surgical anatomical measurement as baseline, we evaluated the accuracy of 3D visualization and verified their utility in computer-aided anatomical analysis. METHODS: The study cohort consisted of 50 adult cadavers fixed with the classical formaldehyde method. The computer-aided anatomical analysis was based on CT images (in DICOM format) acquired by helical scan with contrast enhancement, using a CT vendor provided 3D visualization workstation (Syngo) and a third-party 3D visualization software (Mimics) that was installed on a PC. Automated and semi-automated segmentations were utilized in the 3D visualization workstation and software, respectively. The functionality and efficiency of automated and semi-automated segmentation methods were compared. Using surgical anatomical measurement as a baseline, the accuracy of 3D visualization based on automated and semi-automated segmentations was quantitatively compared. RESULTS: In semi-automated segmentation, the Mimics 3D visualization software outperformed the Syngo 3D visualization workstation. No significant difference was observed in anatomical data measurement by the Syngo 3D visualization workstation and the Mimics 3D visualization software (P>0.05). CONCLUSIONS: Both the Syngo 3D visualization workstation provided by a CT vendor and the Mimics 3D visualization software by a third-party vendor possessed the needed functionality, efficiency and accuracy for computer-aided anatomical analysis.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Programas Informáticos , Adulto , Arterias/anatomía & histología , Automatización , Huesos/anatomía & histología , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Piel/anatomía & histología , Tomografía Computarizada por Rayos X
12.
Int J Med Robot ; 13(3)2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27538708

RESUMEN

BACKGROUND: Percutaneous cervical pedicle screw fixation has been proven to be an effective method of cervical screw instrumentation, which has the advantages of less invasiveness and low blood loss. Emerging evidence has indicated that the cervical spinous process plays an important role in percutaneous spine surgery. However, there is a limited amount of information on the fundamental research of pedicle and its associated imaging parameter measurement. The purpose of this study was to measure the anatomic data of the pedicle screw channel (PSC) using reverse engineering and three-dimensional reconstruction, and also to discuss the three-dimensional relationship between the cervical spinous process and the pedicle screw channel. METHODS: Twenty adult subjects (10 males, 10 females, age range 19-46 years) were studied using the method of three-dimensional CT reconstruction and reverse engineering. The centrum was divided into 10 equal parts from front to back. The bisectors were defined as borderline depths of the centrum, from front to back, 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, 0% of borderline depths were presented. Then, a 3D coordinate system was constructed to measure all the data, including the radius of the inscribed circle, the length of the PSC, the insertion angle, the distances from entry point to cervical spinous process and skin depth. All the indexes were measured from 70% to 90% borderline depth. RESULTS: The radius of the inscribed circles from C3 to C7 at 90% borderline depth were 2.94 ± 0.55 mm, 3.04 ± 0.40 mm, 3.15 ± 0.36 mm, 3.28 ± 0.47 mm, 3.89 ± 0.54 mm, respectively. The lengths of the PSC were between 25 and 32 mm. The insertion angles for 70% to 90% borderline depth were 28.33°, 34.28°, 37.92°, respectively. The relationship between the PSC and spinous process was measured as the distance from the entry point to the end of the spinous process, which were, respectively, 26.91 mm, 28.18 mm, 30.03 mm, 35.67 mm, 41.99 mm from C3 to C7 .The distance from the skin to the entry point of C3-7 increased gradually. CONCLUSIONS: The measurements of this study could provide detailed information for percutaneous cervical screw fixation. The data of the relationship between the cervical spinous process and the pedicle screw channel present valuable technical information for the design, optimization and clinical application of the aiming device for percutaneous cervical pedicle screw fixation. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Imagenología Tridimensional/métodos , Tornillos Pediculares , Adulto , Ingeniería Biomédica , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Enfermedades de la Columna Vertebral/diagnóstico por imagen , Enfermedades de la Columna Vertebral/cirugía , Tomografía Computarizada por Rayos X , Adulto Joven
13.
Ying Yong Sheng Tai Xue Bao ; 27(7): 2239-2248, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-29737132

RESUMEN

Soil samples and environmental factors in 60 plots of 20 communities in the wild fruit forest in Yili valley were investigated, and then the stoichiometric characteristics of soil organic carbon (C), total nitrogen (N), total phosphorus (P) and total potassium (K) in 0-10 cm and 10-20 cm layers and their influencing factors were studied. The results showed that soil C, N, P and K contents in 0-10 cm layer were 73.15, 7.00, 1.14 and 14.74 g·kg-1, respectively. Soil C:N, C:P, C:K, N:P, N:K and P:K were 10.37, 62.73, 5.05, 6.05, 0.48 and 0.08, respectively. Except for K and C:N, the stoichiometric values in 0-10 cm layer were significantly higher than that in 10-20 cm layer. Soil P, K, C:N and P:K presented high stability (CV=8%-24%), while others showed moderate variability (CV=28%-46%). Soil nutrient contents and their stoichiometric ratios differed markedly in different sampling sites, communities and slope aspects. Except the power relationship between C and N, all the soil nutrient contents and their stoichiometric ratios represented quadratic relationships, indicating nonlinear coupling among soil stoichiometric traits. Slope aspect, precipitation and temperature were the main factors influencing soil stoichiometry in the wild fruit forest in Yili region.


Asunto(s)
Bosques , Suelo/química , Carbono/análisis , China , Ecología , Frutas , Nitrógeno/análisis , Fósforo/análisis , Potasio/análisis
14.
World J Gastroenterol ; 21(27): 8373-81, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-26217089

RESUMEN

AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure (ACLF) in chronic hepatitis B (CHB) patients. METHODS: This was a retrospective study of 1457 patients hospitalized for CHB between October 2008 and October 2013 at the Beijing Ditan Hospital, Capital Medical University, China. The patients were divided into two groups: severe acute exacerbation (SAE) group (n = 382) and non-SAE group (n = 1075). The SAE group was classified as the high-risk group based on the higher incidence of ACLF in this group than in the non-SAE group (13.6% vs 0.4%). Two-thirds of SAE patients were randomly assigned to risk-model derivation and the other one-third to model validation. Univariate risk factors associated with the outcome were entered into a multivariate logistic regression model for screening independent risk factors. Each variable was assigned an integer value based on the regression coefficients, and the final score was the sum of these values in the derivation set. Model discrimination and calibration were assessed using area under the receiver operating characteristic curve and the Hosmer-Lemeshow test. RESULTS: The risk prediction scoring model included the following four factors: age ≥ 40 years, total bilirubin ≥ 171 µmol/L, prothrombin activity 40%-60%, and hepatitis B virus DNA > 10(7) copies/mL. The sum risk score ranged from 0 to 7; 0-3 identified patients with lower risk of ACLF, whereas 4-7 identified patients with higher risk. The Kaplan-Meier analysis showed the cumulative risk for ACLF and ACLF-related death in the two risk groups (0-3 and 4-7 scores) of the primary cohort over 56 d, and log-rank test revealed a significant difference (2.0% vs 33.8% and 0.8% vs 9.4%, respectively; both P < 0.0001). In the derivation and validation data sets, the model had good discrimination (C index = 0.857, 95% confidence interval: 0.800-0.913 and C index = 0.889, 95% confidence interval: 0.820-0.957, respectively) and calibration demonstrated by the Hosmer-Lemeshow test (χ (2) = 4.516, P = 0.808 and χ (2) = 1.959, P = 0.923, respectively). CONCLUSION: Using the scoring model, clinicians can easily identify patients (total score ≥ 4) at high risk of ACLF and ACLF-related death early during SAE.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/virología , Técnicas de Apoyo para la Decisión , Hepatitis B Crónica/complicaciones , Insuficiencia Hepática Crónica Agudizada/sangre , Insuficiencia Hepática Crónica Agudizada/diagnóstico , Insuficiencia Hepática Crónica Agudizada/mortalidad , Adulto , Factores de Edad , Área Bajo la Curva , Bilirrubina/sangre , Biomarcadores/sangre , Distribución de Chi-Cuadrado , China , ADN Viral/genética , Progresión de la Enfermedad , Femenino , Virus de la Hepatitis B/genética , Hepatitis B Crónica/sangre , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/mortalidad , Hospitales Universitarios , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico , Protrombina/análisis , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Carga Viral
15.
Hum Vaccin Immunother ; 9(7): 1430-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23571172

RESUMEN

Enterovirus 71 (EV71) is one of the major causative agents for hand, foot and mouth disease (HFMD) in childhood. Nowadays, HFMD or EV71 infections have already become an important public health issue throughout the world. Vaccination may be the most effective measure to control the transmission of the virus. Therefore, to pave EV71 vaccine into human clinical trial, in the present study a comprehensive preclinical safety assessment of inactivated EV71 vaccine including single- and repeat-dose toxicity studies were conducted in rats and cynomolgus monkeys. No abnormal findings were observed in rats following single intramuscular administration with EV71 vaccine (640 U). The results also showed no obvious systemic toxicities from four repetitive intramuscular injections, with a 14-d interval, of two dosages of EV71 vaccine in the two animal species. Antinuclear antibody response was not detected after the repeated administrations. Histopathological examination demonstrated the minimal to severe inflammatory changes in muscle tissues of the injection sites in EV71 vaccine-injected animals and most of findings have been improved over time. Furthermore, test article could induce highly EV71-specfic neutralizing antibody response in both animal species. Taken together, these data suggested a favorable safety profile for inactivated EV71 vaccine and supported this product to enter human phase I clinical trial.


Asunto(s)
Enterovirus Humano A/inmunología , Enfermedad de Boca, Mano y Pie/inmunología , Enfermedad de Boca, Mano y Pie/prevención & control , Vacunas Virales/efectos adversos , Vacunas Virales/uso terapéutico , Animales , Anticuerpos Antinucleares/sangre , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Femenino , Macaca fascicularis , Masculino , Ratas , Ratas Wistar , Vacunas de Productos Inactivados/efectos adversos , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/uso terapéutico , Vacunas Virales/inmunología
16.
Surg Radiol Anat ; 30(5): 437-42, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18414767

RESUMEN

The aim of this study was to establish a 3D digitized model of pelvic vasculature for anatomic study, preoperative planning, and virtual reality. Three adult fresh cadavers were perfused with carboxymethyl cellulose/lead oxide mixture to mark blood vessels, and subjected to multilayer spiral computed tomography scanning to obtain a series of thin sections. Then, the 2D images of the pelvis and pelvic blood vessels were transformed into 3D digitized models using Mimics 11.0. The 2D images of carboxymethyl cellulose/lead oxide filled arteries had the features of entire outline and few constructed defects. The 3D digitized models of the pelvis and pelvic artery system displayed spatial location and the adjacent relationship of arteries with the pelvis. Not only the well-known arteries but also the tiny blood vessels in the reconstructed structures were well demonstrated and observed interactively. The reconstructed tissue flaps, including a lobulated skin flap with the pedicle of superficial epigastric artery, and an iliac flap with the pedicle of deep iliac circumflex artery, demonstrated their blood supply area. This indicated that the modified technique of vascular perfusion with carboxymethyl cellulose/lead oxide and reconstitution with Mimics 11.0 software contributed to 3D digitized model of pelvic vasculature.


Asunto(s)
Imagenología Tridimensional/métodos , Pelvis/irrigación sanguínea , Carboximetilcelulosa de Sodio , Femenino , Humanos , Plomo , Masculino , Persona de Mediana Edad , Modelos Anatómicos , Óxidos , Pelvis/anatomía & histología , Pelvis/diagnóstico por imagen , Colgajos Quirúrgicos/irrigación sanguínea , Tomografía Computarizada Espiral , Adulto Joven
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