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1.
J Nanobiotechnology ; 22(1): 485, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138462

RESUMEN

Nanozymes are promising antimicrobials, as they produce reactive oxygen species (ROS). However, the intrinsic lack of selectivity of ROS in distinguishing normal flora from pathogenic bacteria deprives nanozymes of the necessary selectivities of ideal antimicrobials. Herein, we exploit the physiological conditions of bacteria (high alkaline phosphatase (ALP) expression) using a novel CuO nanoparticle (NP) nanoenzyme system to initiate an ALP-activated ROS prodrug system for use in the on-demand precision killing of bacteria. The prodrug strategy involves using 2-phospho-L-ascorbic acid trisodium salt (AAP) that catalyzes the ALP in pathogenic bacteria to generate ascorbic acid (AA), which is converted by the CuO NPs, with intrinsic ascorbate oxidase- and peroxidase-like activities, to produce ROS. Notably, the prodrug system selectively kills Escherichia coli (pathogenic bacteria), with minimal influence on Staphylococcus hominis (non-pathogenic bacteria) due to their different levels of ALP expression. Compared to the CuO NPs/AA system, which generally depletes ROS during storage, CuO NPs/AAP exhibits a significantly higher stability without affecting its antibacterial activity. Furthermore, a rat model is used to indicate the applicability of the CuO NPs/AAP fibrin gel in wound disinfection in vivo with negligible side effects. This study reveals the therapeutic precision of this bifunctional tandem nanozyme platform against pathogenic bacteria in ALP-activated conditions.


Asunto(s)
Fosfatasa Alcalina , Antibacterianos , Cobre , Desinfección , Escherichia coli , Profármacos , Especies Reactivas de Oxígeno , Cobre/química , Cobre/farmacología , Animales , Profármacos/farmacología , Profármacos/química , Fosfatasa Alcalina/metabolismo , Ratas , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Desinfección/métodos , Ácido Ascórbico/farmacología , Ácido Ascórbico/química , Ácido Ascórbico/análogos & derivados , Nanopartículas del Metal/química , Ratas Sprague-Dawley , Masculino
2.
Int J Surg ; 109(7): 1910-1918, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37133988

RESUMEN

BACKGROUND: Osteoporotic vertebral fractures cause pain and disability, which result in a heavy socioeconomic burden. However, the incidence and cost of vertebral fractures in China are unknown. We aimed to assess the incidence and cost of clinically recognized vertebral fractures among people aged 50 years and older in China from 2013 to 2017. MATERIALS AND METHODS: This population-based cohort study was conducted by using Urban Employee Basic Medical Insurance (UEBMI) and Urban Resident Basic Medical Insurance (URBMI) data in China from 2013 to 2017, which covered more than 95% of the Chinese population in urban areas. Vertebral fractures were identified by the primary diagnosis (i.e. International Classification of Diseases code or text of diagnosis) in UEBMI and URBMI. The incidence and medical cost of these clinically recognized vertebral fractures in urban China were calculated. RESULTS: A total of 271 981 vertebral fractures (186 428, 68.5% females and 85 553, 31.5% males) were identified, with a mean age of 70.26 years. The incidence of vertebral fractures among patients aged 50 years and over in China increased ~1.79-fold during the 5 years, from 85.21 per 100 000 person-years in 2013 to 152.13 per 100 000 person-years in 2017. Medical costs for vertebral fractures increased from US$92.74 million in 2013 to US$505.3 million in 2017. Annual costs per vertebral fracture case increased from US$3.54 thousand in 2013 to US$5.35 thousand in 2017. CONCLUSION: The dramatic increase in the incidence and cost of clinically recognized vertebral fractures among patients aged 50 and over in urban China implies that more attention should be given to the management of osteoporosis to prevent osteoporotic fractures.


Asunto(s)
Fracturas de Cadera , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Fracturas de la Columna Vertebral/epidemiología , Estudios de Cohortes , Incidencia , China/epidemiología
3.
Ying Yong Sheng Tai Xue Bao ; 33(7): 1810-1818, 2022 Jul.
Artículo en Chino | MEDLINE | ID: mdl-36052783

RESUMEN

We investigated the decomposition characteristics of Eragrostis minor, mosses, and leaves of Artemisia ordosica with litterbag method in the sand-binding revegetation area, southeastern edge of the Tengger Desert, and further examined their effects on soil microbial communities using the Illumina MiSeq sequencing method. The results showed that the decomposition duration and litter types significantly affected litter decomposition rate. Mosses had the lowest decomposition rate, with a mass loss ratio of only 15.4% after decomposition for 13 months. The average decomposition rates of E. minor and leaves of A. ordosica were 4.9 and 3.4-fold of that of mosses, respectively. During decomposition for 11 months, the dominant bacterial phyla were Actinomycota and Proteobacteria, while that of the fungal community was Ascomycota. Moss decomposition significantly increased the relative abundance of Bacteroidetes and Chloroflexi, but remarkedly decreased the abundance of Basidiomycetes. The diversity and richness of bacterial and fungal communities significantly increased after litter decomposition. The compositional changes of fungal community were significant among litters, but that of bacterial community was not. There was a negative correlation between decomposition rate and the diversity and richness of bacterial and fungal communities. Plant polysaccharides, total phosphorus, soil pH, microbial biomass nitrogen, and soil ammonium content were the main factors affecting microbial community structure. Litter decomposition changed the composition and interspecific similarity within microbial communities, as well as increased the diversity and richness of soil microbial communities, and thus would promote the restoration of soil habitat.


Asunto(s)
Microbiota , Micobioma , Bacterias , China , Ecosistema , Hojas de la Planta/microbiología , Suelo/química , Microbiología del Suelo
4.
Chin Med J (Engl) ; 133(1): 41-48, 2020 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-31923103

RESUMEN

BACKGROUND: The purpose of this study was to analyze cases of AO31-A2 intertrochanteric fractures (ITFs) and to identify the relationship between the loss of the posteromedial support and implant failure. METHODS: Three hundred ninety-four patients who underwent operative treatment for ITF from January 2003 to December 2017 were enrolled. Focusing on posteromedial support, the A2 ITFs were divided into two groups, namely, those with (Group A, n = 153) or without (Group B, n = 241) posteromedial support post-operatively, and the failure rates were compared. Based on the final outcomes (failed or not), we allocated all of the patients into two groups: failed (Group C, n = 66) and normal (Group D, n = 328). We separately analyzed each dataset to identify the factors that exhibited statistically significant differences between the groups. In addition, a logistic regression was conducted to identify whether the loss of posteromedial support of A2 ITFs was an independent risk factor for fixation failure. The basic factors were age, sex, American Society of Anesthesiologists (ASA) score, side of affected limb, fixation method (intramedullary or extramedullary), time from injury to operation, blood loss, operative time and length of stay. RESULTS: The failure rate of group B (58, 24.07%) was significantly higher than that of group A (8, 5.23%) (χ = 23.814, P < 0.001). Regarding Groups C and D, the comparisons of the fixation method (P = 0.005), operative time (P = 0.001), blood loss (P = 0.002) and length of stay (P = 0.033) showed that the differences were significant. The logistic regression revealed that the loss of posteromedial support was an independent risk factor for implant failure (OR = 5.986, 95% CI: 2.667-13.432) (P < 0.001). CONCLUSIONS: For AO31-A2 ITFs, the loss of posteromedial support was an independent risk factor for fixation failure. Therefore, posteromedial wall reconstruction might be necessary for the effective treatment of A2 fractures that lose posteromedial support.


Asunto(s)
Fracturas de Cadera/cirugía , Fijación Interna de Fracturas , Fijación Intramedular de Fracturas , Humanos , Modelos Logísticos , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
5.
Orthop Surg ; 12(1): 224-232, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31958886

RESUMEN

OBJECTIVE: To assess the therapeutic effect of a novel tension band using 3.0 mm cannulated screw combined with a titanium cable and specific shims comparatively with patellotibial tubercle cerclage in comminuted fractures of the inferior pole of the patella. METHODS: The retrospective study from March 2012 to July 2017 was conducted in Peking University Third Hospital and comprised 63 patients with comminuted fractures of the inferior pole of the patella: 41 treated with new tension band using 3.0 mm cannulated screw combined with a titanium cable and specific shims (new tension band group) and 22 with patellotibial tubercle cerclage (tubercle cerclage group). Gender, age, AO/OTA fracture type, injury mechanism, inter-fragmentary gap, and follow-up time of patients were recorded. Two groups were compared regarding: operation time, blood loss, partial weight-bearing time, fracture-healed time, Bostman score and knee mobility at 12-month follow-up, and postoperative complications. Continuous and categorical parameters were analyzed by Mann-Whitney U test and the chi-squared test, respectively. Fisher's exact test was used for small data subsets. RESULTS: Between the two groups, no statistically significant difference was found in mean age, gender, AO/OTA fracture type, injury mechanism, mean inter-fragmentary gap, or mean follow-up time (P > 0.05). The mean operation time of new tension band group was significantly longer than that of tubercle cerclage group (76.4 min vs 64.2 min, P = 0.006), while there was no significant difference in blood loss. After surgery, new tension band group had a significantly earlier mean partial weight-bearing time (5.2 weeks vs 7.4 weeks, P < 0.001) and fracture-healed time (9.6 weeks vs 11.6 weeks, P < 0.001). At 12-month follow-up, patients of new tension band group had a significantly higher mean Bostman score (28.5 vs 25.8, P < 0.001) and knee mobility (126.7 vs 117.3, P < 0.001). Ten complications related with internal fixation were found in tubercle cerclage group including two cases of loose internal fixation, two cases of cerclage breakage, and six cases of low patella position who undertook secondary operation. No complications were found in new tension band group (0 in 41 vs 10 in 22, P < 0.001). CONCLUSION: Patients with comminuted fractures of the inferior pole of the patella treated with a novel tension band experienced a longer operation time, but earlier partial-weight-bearing and fracture-healed time, better clinical outcomes at 12-month follow-up, and less complications. It should be considered an alternative therapy for the treatment of distal pole patellar fractures.


Asunto(s)
Tornillos Óseos , Hilos Ortopédicos , Fijación Interna de Fracturas/instrumentación , Fracturas Conminutas/cirugía , Rótula/cirugía , Adulto , Anciano , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Encuestas y Cuestionarios
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 1943-1948, 2019 Dec.
Artículo en Chino | MEDLINE | ID: mdl-31839064

RESUMEN

OBJECTIVE: To investigate the gene mutation types and gene carrying rate of common thalassemia in patients with thalassemia in Quanzhou, and to analyze its molecular epidemiological characteristics in Quanzhou. METHODS: 546 patients with thalassemia diagnosed at the first hospital of Quanzhou from January 2017 to October 2018 were collected and retrospectively analyzed for their types of mutations and carrier rates. RESULTS: Among the 4226 samples submitted, 546 positive samples were detected, the total carrying rate of the thalassaemia genes was 12.92%; the carrier rate of α-thalassemia was 8.16%; the carrier rate of ß-thalassemia was 4.76%; There were more α-thalassemia missing patients than non-deleted patients. The Southeast Asian deletion type (--SEA /αα) was the most common one, with a composition ratio of 68.98%, which was followed by 22.61% (-α3.7/αα), 2.61% (αWSα/αα), and 2.32% (ααCS/αα), 2.32% (αQSα/αα), 1.16% (-α4.2/αα); 9 types of ß-thalassemia gene mutations were detected. The most common three mutations were IVSII-654 (C→T, 42.29%), CD41-42 (-TTCT, 33.83%), CD17 (A→T, 12.94%). 2 cases of --THAI/αα , 1 case of αα/αααanti3.7 and 1 case of HKαα were detected. CONCLUSION: This study shows that the gene carrying rate of thalassemia in Quanzhou is high and has diversity, which can provide some reference for the prevention and control of thalassemia in Quanzhou.


Asunto(s)
Mutación , Talasemia alfa , Talasemia beta , China , Genotipo , Humanos , Estudios Retrospectivos
7.
Chin Med J (Engl) ; 132(21): 2534-2542, 2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31658157

RESUMEN

BACKGROUND: Reverse intertrochanteric fractures are usually initially treated with closed reduction. However, sometimes these fractures are not amenable to closed reduction and require open reduction. To date, few studies have been conducted on predictors of and reduction techniques for irreducible reverse intertrochanteric fractures. Therefore, this study aimed to summarize the displacement patterns of irreducible reverse intertrochanteric fractures and corresponding reduction techniques, and explore predictors of irreducibility. METHODS: We reviewed 1174 cases of trochanteric fractures treated in our hospital from January 2006 to October 2018, 113 of which were reverse intertrochanteric fractures. An irreducible fracture was determined according to intra-operative fluoroscopy imaging after closed manipulation. Fractures were assessed for displacement patterns, radiographic features of irreducibility, and reduction techniques. Logistic regression analysis was performed on potential predictors for irreducibility, including gender, age, body mass index, AO Foundation/Orthopaedic Trauma Association (AO/OTA) classification, and radiographic features. RESULTS: Seventy-six irreducible fractures were identified, accounting for 67% of reverse intertrochanteric fractures. Six patterns of fracture displacement after closed manipulation were identified; the most common pattern was medial displacement and posterior sagging of the femoral shaft relative to the head-neck fragment. Multivariate logistic regression analysis identified three predictors of irreducibility: a medially displaced femoral shaft relative to the head-neck fragment on the anteroposterior (AP) view (odds ratio [OR], 8.00; 95% confidence interval [CI], 3.04-21.04; P < 0.001), a displaced lesser trochanter (OR, 3.61; 95% CI, 1.35-9.61; P = 0.010), and a displaced lateral femoral wall (OR, 2.92; 95% CI, 1.02-8.34; P = 0.046). CONCLUSIONS: A high proportion of reverse intertrochanteric fractures are not amenable to closed reduction. Six patterns of fracture displacement after closed manipulation were identified. Different reduction techniques are required for different displacement patterns. Predictors of irreducibility include a medially displaced femoral shaft relative to the head-neck fragment on the AP view, a displaced lesser trochanter, and a displaced lateral femoral wall. These patients warrant special consideration in terms of recognition and management.


Asunto(s)
Fracturas de Cadera/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Clavos Ortopédicos , Tornillos Óseos , Femenino , Fracturas de Cadera/cirugía , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad
8.
Oncol Lett ; 17(6): 4907-4913, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31186699

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is one of the most common types of kidney cancer and is accompanied by a poor prognosis due to a high potential for metastasis and recurrence. The mechanism of ccRCC metastasis is not well known. N-lysine methyltransferase KMT5A serves a crucial role in the progression of human cancer; however, the function of KMT5A in the development of ccRCCs has not yet been investigated, which has triggered an interest in investigating the potential association between KMT5A and ccRCC. The present study demonstrates for the first time that KMT5A is a driving factor in ccRCC metastasis. The KMT5A expression level was revealed to be significantly higher in ccRCC tissues compared with adjacent normal tissues. Patients with ccRCC whose tumors expressed high levels of KMT5A were demonstrated to have significantly shorter postoperative survival times. In vitro knockdown of KMT5A expression in 786-O cells inhibited cell migration and invasion. KMT5A reduced cadherin-1 (CDH1) protein levels by directly inhibiting its transcription. The CDH1 mRNA levels were inversely correlated with KMT5A expression in ccRCC samples. Patients with high tumor KMT5A or low CDH1 levels had the poorest prognosis with the shortest overall survival (OS) time, and this combination was demonstrated to be an independent prognostic indicator for patient OS time in ccRCC, more accurate than monitoring KMT5A or CDH1 alone. Together, these results indicate that KMT5A serves a vital role in ccRCC development and progression, and it may be a novel target for ccRCC treatment and prevention.

9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(5): 1453-1458, 2018 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30295267

RESUMEN

OBJECTIVE: To investigate the gene prevalence and spectrum of thalassemia in the women of childbearing age in quanzhou area. METHODS: Venous blood of the women were collected for study, all subjects were registered in each county of quanzhou area by using cluster sampling. Both the mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were used for screening thalassemia.Genotyping of the screened positive samples was performed by gap single polymerase chain reaction (gap-PCR) and reverse dot blot (RDB) hybridization.Unknown positive samples were analyzed with DNA sequencing. RESULTS: Out of all 7 082 samples, Three hundred and eighty four were identified as thalassemia gene carriers with a carrying rate of 5.42 %. The α and ß thalassemia were 3.21% and 2.15% respectively. --SEA /αα was the most common genotype with 68.72 % in mutation types of α thalassemia, In addition gene, 2 cases of --THAI/αα and 1 case of αα/αααanti3.7 were also detected. IVS-Ⅱ-654/N and CD41-42/N were the most common gentypes with 75.00 % in mutation types of ß thalassemia gene, 5 cases were found to be α ß compogite thalassemia. CONCLUSION: The carrying rate of thalassemia gene in quanzhou area is higher, and with the most common gentypes including --SEA /αα、IVSⅡ-654(C→T)/N and CD41-42(-TTCT)/N. The study results are beneficial for the screening of thalassemia in the genetic consultation and the prenatal gene diagnosis.


Asunto(s)
Talasemia alfa , Talasemia beta , China/epidemiología , Femenino , Heterocigoto , Humanos , Mutación , Embarazo , Encuestas y Cuestionarios , Talasemia alfa/epidemiología , Talasemia beta/epidemiología
10.
Glob Chang Biol ; 24(10): 4960-4971, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29957890

RESUMEN

Biological soil crusts across the desert regions play a key role in regional ecological security and ecological health. They are vital biotic components of desert ecosystems that maintain soil stability, fix carbon and nitrogen, influence the establishment of vascular plants, and serve as habitats for a large number of arthropods and microorganisms, as well as influencing soil hydrological processes. Changes in temperature and precipitation are expected to influence the functioning of desert ecosystems by altering biotic components such as the species composition of biological soil crusts. However, it remains unclear how these important components will respond to the prolonged warming and reduced precipitation that is predicted to occur with climate change. To evaluate how the hydrological properties of these biological soil crusts respond to these alterations, we used open-top chambers over a 10-year period to simulate warming and reduced precipitation. Infiltration, dew entrapment, and evaporation were measured as surrogates of the hydrological functioning of biological soil crusts. It was found that the ongoing warming coupled with reduced precipitation will more strongly affect moss in crustal communities than lichens and cyanobacteria, which will lead to a direct alteration of the hydrological performance of biological soil crusts. Reductions in moss abundance, surface cover, and biomass resulted in a change in structure and function of crustal communities, decreased dew entrapment, and increased infiltration and evaporation of biological soil crusts in desert ecosystems, which further impacted on the desert soil water balance.


Asunto(s)
Simulación por Computador , Clima Desértico , Calentamiento Global , Microbiología del Suelo , Suelo/química , Agua/análisis , Biomasa , Carbono/análisis , Nitrógeno/análisis , Lluvia , Temperatura
11.
Mitochondrial DNA B Resour ; 3(2): 1156-1157, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-33490566

RESUMEN

We sequenced and characterized the complete mitochondrial genome of golden yellow snakehead fish, Channa argus. The mitogenomes contained the typical complement of 13 protein-coding genes, 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs), and a non-coding control region. They share the same gene arrangement pattern that was identical with most vertebrates. The entire mitochondrial DNA molecule of golden yellow snakehead fish was 16,558 bp long. All information reported in this article will be a useful source of sequence information for general molecular and evolutionary studies of the family Channidae.

12.
BMC Infect Dis ; 17(1): 599, 2017 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-28854892

RESUMEN

BACKGROUND: Rabies is a global fatal infectious viral disease that is characterized by a high mortality after onset of clinical symptoms. Recently, there has been an increase in the incidence of rabies in China. The aim of this study was to investigate the incidence of human rabies and characterize the rabies virus nucleoprotein gene in dogs sampled from Fujian Province, Southeast China from 2002 to 2012. METHODS: Data pertaining to human rabies cases in Fujian Province during the period from 2002 through 2012 were collected, and the epidemiological profiles were described. The saliva and brain specimens were collected from dogs in Quanzhou, Longyan and Sanming cities of the province, and the rabies virus antigen was determined in the canine saliva specimens using an ELISA assay. Rabies virus RNA was extracted from canine brain specimens, and rabies virus nucleoprotein gene was amplified using a nested RT-PCR assay, followed by sequencing and genotyping. RESULTS: A total of 226 human rabies cases were reported in Fujian Province from 2002 to 2012, in which 197 cases were detected in three cities of Quanzhou, Longyan and Sanming. ELISA assay revealed positive rabies virus antigen in six of eight rabid dogs and 165 of 3492 seemingly healthy dogs. The full-length gene fragment of the rabies virus nucleoprotein gene was amplified from the brain specimens of seven rabid dogs and 12 seemingly healthy dogs. Sequence alignment and phylogenetic analysis revealed that these 19 rabies virus nucleoprotein genes all belonged to genotype I, and were classified into three genetic groups. Sequencing analysis showed a 99.7% to 100% intra-group and an 86.4% to 89.3% inter-group homology. CONCLUSIONS: This study is the first description pertaining to the epidemiological characteristics of human rabies cases and characterization of the rabies virus nucleoprotein gene in dogs in Fujian Province, Southeast China. Our findings may provide valuable knowledge for the development of strategies targeting the prevention and control of rabies.


Asunto(s)
Nucleoproteínas/genética , Virus de la Rabia/genética , Rabia/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antígenos Virales/análisis , Encéfalo/virología , Niño , Preescolar , China/epidemiología , Enfermedades de los Perros/virología , Perros , Ensayo de Inmunoadsorción Enzimática , Femenino , Genotipo , Humanos , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Filogenia , Rabia/veterinaria , Rabia/virología , Virus de la Rabia/patogenicidad , Saliva/virología , Adulto Joven
13.
Sci Rep ; 6: 26030, 2016 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-27184918

RESUMEN

In water-limited regions, rainfall interception is influenced by rainfall properties and crown characteristics. Rainfall properties, aside from gross rainfall amount and duration (GR and RD), maximum rainfall intensity and rainless gap (RG), within rain events may heavily affect throughfall and interception by plants. From 2004 to 2014 (except for 2007), individual shrubs of Caragana korshinskii and Artemisia ordosica were selected to measure throughfall during 210 rain events. Various rainfall properties were auto-measured and crown characteristics, i.e., height, branch and leaf area index, crown area and volume of two shrubs were also measured. The relative interceptions of C. korshinskii and A. ordosica were 29.1% and 17.1%, respectively. Rainfall properties have more contributions than crown characteristics to throughfall and interception of shrubs. Throughfall and interception of shrubs can be explained by GR, RI60 (maximum rainfall intensities during 60 min), RD and RG in deceasing importance. However, relative throughfall and interception of two shrubs have different responses to rainfall properties and crown characteristics, those of C. korshinskii were closely related to rainfall properties, while those of A. ordosica were more dependent on crown characteristics. We highlight long-term monitoring is very necessary to determine the relationships between throughfall and interception with crown characteristics.

14.
Ying Yong Sheng Tai Xue Bao ; 27(4): 1024-1030, 2016 Apr 22.
Artículo en Chino | MEDLINE | ID: mdl-29732755

RESUMEN

The objective of this study was to investigate species composition, and predict future development of dominant species on semi-fixed sand dunes in the Gurbantongut Desert. Using the plant height, crown area and volume instead of age structure, the growth and development condition of dominant shrub populations were analyzed. The results showed that totally 23 species were observed, of which Chenopodiaceae occurred the most with 6 genera 8 species, followed by Asteraceae with 5 genera 6 species. The vegetation community of Gurbantunggut Desert was characterized by few species, and simple structure. As a dominant species, Haloxylon persicum was distributed mainly on the top of the dunes and was a stable increasing population. However, the number of H. ammodendron was small. Artemisia ordosica, as an exotic species introduced by vegetation restoration after construction, covered mainly in the windward and the top of dunes. The po-pulation of A. ordosica had an increasing age structure with a strongly increasing potential, which has affected local species composition. The populations of Calligonum leucocladum and Ephedra distachya were lack of seedlings and had few saplings, resulting in the declining age structure. Due to the same distribution habitat, C. leucocladum might be replaced by A. ordosica in the future.


Asunto(s)
Asteraceae/clasificación , Chenopodiaceae/clasificación , Clima Desértico , Ecosistema , Artemisia , China , Especies Introducidas , Dinámica Poblacional
15.
Ying Yong Sheng Tai Xue Bao ; 26(4): 1113-20, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26288862

RESUMEN

Two types of soil covered by biological soil crusts (BSCs) , i.e. moss and algae, and moving sand in the natural vegetation area at the southeast fringe of the Tengger Desert were collected intactly. They were incubated continuously for 20 days under two different temperatures (15 degrees C and 25 degrees C) and moistures (10% and 25%) condition in the laboratory, and soil NO3(-)-N contents were measured after 1, 2, 5, 8, 12, 20 days of incubation and net nitrification rate was evaluated during dehydration. The results showed that NO3(-)-N content of the moss-covered soil (2.29 mg x kg(-1)) was higher than that of the algae-covered soil (1.84 mg x kg(-1)) and sand (1.59 mg x kg(-1)). Net nitrification rate of the three soil types ranged from -3.47 to 2.97 mg x kg(-1) x d(-1). For the moss-covered soil and algae-covered soil at 10% and 25% moisture levels, the net nitrification rates at 15 degrees C were 75.1%, 0.7% and 99.1%, 21.3% higher than those at 25 degrees C, respectively. Also, the net nitrification rates at 15 degrees C and 10% moisture levels were 193.4% and 107.3% higher than those at 25 degrees C and 25% moisture levels, respectively. The results suggested that regardless of soil moisture increasing or decreasing under the global warming senior, the net nitrification rate of BSCs-soil system in the desert would probably be limited to some extent during drought process.


Asunto(s)
Sequías , Nitrificación , Suelo/química , Temperatura , Agua , Briófitas , China , Clima Desértico , Ecosistema , Plantas , Dióxido de Silicio , Microbiología del Suelo
16.
Injury ; 46(6): 1161-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25818053

RESUMEN

INTRODUCTION: Difficult removal of locking plates including less invasive stabilisation systems (LISSs) and locking compression plates (LCPs) sometimes occur. However, investigations of the mechanisms and correlated factors of complicated removal remain scant. This study aims to identify correlated factors for the difficult removal of locking plates and to propose suggestions for decision making regarding implant removal and the prevention of complicated removal. MATERIALS AND METHODS: In total, 308 consecutive patients who underwent LCP/LISS removal from Sep. 2004 to Nov. 2013 were assessed. Using the Mann-Whitney U test, we analysed the correlation between difficult removal and the duration between open reduction and internal fixation (ORIF) and implant removal as well as the correlation between difficult removal and the patients' age. Using Chi Square test, we assessed the correlations between complicated removal and the size, location, insertion technique and cortical purchase of the locking head screw (LHS). Correlated factors were separately determined in upper and lower extremities. Rates of difficult removal in different fracture locations were evaluated, and postoperative complications were documented. RESULTS: Of the total 308 patients, thirty-seven had intra-operative difficulties, and six patients experienced postoperative complications. Six out of fifteen patients with peri-elbow fractures and five out of seventeen patients with femur fractures suffered difficult removal, while four out of one hundred patients with malleolar fractures had intra-operative difficulties. Difficulties were experienced with 30 of 338 LCPs, 7 of 32 LISSs, 67 of 1533 small-diameter (≤ 3.5-mm) LHSs, and 12 of 442 large-diameter (≥ 4.5-mm) LHSs. Three LCPs and seventeen small-diameter LHSs were retained. A longer interval between ORIF and removal, younger age and bicortical screws correlated with difficult removal in the upper extremities, and a longer duration before removal, small-diameter LHS and minimally invasive insertion of LHS were predictors in the lower extremities. CONCLUSIONS: Complications occur with LCP/LISS removal, and it should not be a routine procedure. If removal is indicated, performing surgery as soon as radiographs show fracture healing is recommended. Different considerations should apply when making decisions and removing implants from patients with different fracture sites.


Asunto(s)
Remoción de Dispositivos , Fracturas del Fémur/cirugía , Fijación Interna de Fracturas/instrumentación , Cabeza Humeral/cirugía , Complicaciones Posoperatorias/cirugía , Fracturas del Radio/cirugía , Adulto , Placas Óseas , Tornillos Óseos , Estudios de Casos y Controles , Remoción de Dispositivos/métodos , Femenino , Humanos , Masculino , Falla de Prótesis , Factores de Riesgo , Factores de Tiempo
17.
Eur Spine J ; 24(5): 975-84, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25542384

RESUMEN

PURPOSE: Tracheostomy may become indispensable for patients with acute traumatic cervical spinal cord injuries. However, the early prediction of a tracheostomy is often difficult. Previous prediction models using the pulmonary function test (PFT) have limitations because some severely injured patients could not provide acceptable PFT results. We aim to develop an alternative model for predicting tracheostomy using accessible data obtained from the bedside. METHOD: Clinical, neurological and radiological data from 345 consecutive patients with acute tetraplegia were retrospectively reviewed. We applied multiple logistic regression analysis (MLRA) and classification and regression tree (CART) analysis to develop the prediction model for tracheostomy. By train-test cross-validation, we used the sensitivity, specificity, area under the receiver operating characteristics curve (AUC) and correction rate to evaluate the performance of these models. RESULTS: According to the American Spinal Injury Association (ASIA) standards, an admission ASIA motor score (AAMS) ≤ 22, ASIA grade A and presence of respiratory complications were identified as independent predictors of tracheostomy by both models. The model derived by CART suggested that the highest signal change (HSC) in the spinal cord on magnetic resonance imaging (MRI) also affected a patient's requirement for a tracheostomy, while MLRA demonstrated that tracheostomy was also influenced by the presence of an ASIA grade B injury. The CART model had a sensitivity of 73.7%, specificity of 89.7%, AUC of 0.909 and overall correction rate of 87.3%. The sensitivity, specificity, AUC and correction rate of the MLRA model were 81.8, 86.4, 0.889 and 85.7%, respectively. CONCLUSIONS: We suggest using the CART model in clinical applications. Patients with AAMS ≤ 1 exhibit an increased likelihood of requiring a tracheostomy. For patients with an AAMS in the range of 2-22, surgeons should consider giving these patients a tracheostomy once respiratory complications occur. Surgeons should be cautious to give a tracheostomy to patients with an AAMS ≥ 23, if the patient experiences an incomplete spinal cord injury and the HSC in the spinal cord is at C3 level or lower based on MRI. For other patients, close observation is necessary; generally, patients with complete SCI might require a tracheostomy more frequently.


Asunto(s)
Médula Cervical/lesiones , Vértebras Cervicales/lesiones , Traumatismos de la Médula Espinal/cirugía , Traqueostomía , Adulto , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Pronóstico , Cuadriplejía/etiología , Pruebas de Función Respiratoria , Enfermedades Respiratorias/etiología , Enfermedades Respiratorias/cirugía , Estudios Retrospectivos , Medición de Riesgo/métodos , Factores de Riesgo , Sensibilidad y Especificidad , Traumatismos de la Médula Espinal/complicaciones
18.
Mol Med Rep ; 11(2): 1009-16, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25371092

RESUMEN

There is currently no effective vaccine to prevent dengue infection, despite the existence of multiple studies on potential methods of immunization. The aim of the present study was to explore the effect of DNA and/or recombinant protein on levels of neutralizing antibodies. For this purpose, envelope domain IIIs of dengue serotypes 1 and 2 (DEN-1/2)were spliced by a linker (Gly­Gly­Ser­Gly­Ser)3 and cloned into the prokaryotic expression plasmid pET30a (+) and eukaryotic vector pcDNA3.1 (+). The chimeric bivalent protein was expressed in Escherichia coli, and one­step purification by high­performance liquid chromatography was conducted. Protein expression levels of the DNA plasmid were tested in BHK­21 cells by indirect immunofluorescent assay. In order to explore a more effective immunization strategy and to develop neutralizing antibodies against the two serotypes, mice were inoculated with recombinant bivalent protein, the DNA vaccine, or the two given simultaneously. Presence of the specific antibodies was tested by ELISA and the presence of the neutralizing antibodies was determined by plaque reduction neutralization test. Results of the analysis indicated that the use of a combination of DNA and protein induced significantly higher titers of neutralizing antibodies against either DEN­1 or DEN­2 (1:64.0 and 1:76.1, respectively) compared with the DNA (1:24.7 and 1:26.9, DEN­1 and DEN­2, respectively) or the recombinant protein (1:34.9 and 1:45.3 in DEN­1 and DEN­2, respectively). The present study demonstrated that the combination of recombinant protein and DNA as an immunization strategy may be an effective method for the development of a vaccine to prevent dengue virus infection.


Asunto(s)
Anticuerpos Neutralizantes/farmacología , Dengue/inmunología , Proteínas Recombinantes/inmunología , Vacunas de ADN/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Antivirales/inmunología , Virus del Dengue , Ensayo de Inmunoadsorción Enzimática , Escherichia coli/metabolismo , Inmunización , Ratones , Ratones Endogámicos BALB C , Pruebas de Neutralización , Plásmidos
19.
PLoS One ; 9(9): e106600, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25191856

RESUMEN

Esophageal carcinoma is one of the world's deadliest cancers. Esophageal squamous cell carcinoma (ESCC) is more frequent than adenocarcenoma (AC) in China. Platinum-based chemotherapy with surgical resection is a common treatment approach for ESCC; however, the treatment response is uncertain. Evidence suggests polymorphisms in genes encoding excision repair cross-complementing group 1 (ERCC1), a protein involved in nuclear excision repair (NER), may help predict response to cisplatin and other platinum-based chemotherapeutics. Multiple ERCC1 single nucleotide polymorphisms (SNPs) have been associated with platinum chemotherapy response. Two common SNPs occur at the C8092A and C118T loci. Our study aimed to determine if 1) an association exists between ERCC1 tumor expression and patient survival, 2) whether adjuvant therapy influence on survival is related to histological ERCC1 presence in tumor cell nuclei, and 3) whether other clinicopathological characteristics in a cohort of patients following surgery for various stages of ESCC are associated with tumor ERCC1 expression. One hundred eight patients were included in the study, and tumor biopsy was collected for genotyping and immunohistochemical analysis of ERCC1. Sixty-seven patients (62%) received no adjuvant therapy, and the rest had either platinum-based chemotherapy (28.5%), radiotherapy (6.5%) or both treatments (2.8%). Log-rank analysis revealed no significant connection between tumor ERCC1 expression (P = 0.12) or adjuvant therapy (P = 0.56) on patient survival. Also, non-parametric Mann-Whitney analysis showed no significant link between tumor size or nodus tumor formation and ERCC1 presence in patients in the study. Interestingly, C8092A SNP showed significant association with patient survival (P = 0.01), with patients homozygous for the mutant allele showing the most significantly reduced survival (P = 0.04) compared to those homozygous for the dominant allele (CC). Our results provide novel insight into the genotypic variation of patients from Quanzhou, Fujian province China.


Asunto(s)
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidad , Proteínas de Unión al ADN/genética , Endonucleasas/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidad , Polimorfismo de Nucleótido Simple , Anciano , Alelos , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Supervivencia Celular , Transformación Celular Neoplásica/genética , Quimioterapia Adyuvante , China , Análisis Mutacional de ADN , Proteínas de Unión al ADN/metabolismo , Endonucleasas/metabolismo , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas de Esófago , Femenino , Expresión Génica , Genotipo , Humanos , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Radioterapia Adyuvante
20.
Ying Yong Sheng Tai Xue Bao ; 25(1): 61-8, 2014 Jan.
Artículo en Chino | MEDLINE | ID: mdl-24765843

RESUMEN

Uncertainties still existed for evaluating greenhouse gases fluxes (GHGs), including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) at the regional scale for desert ecosystem because available GHGs data about biological soil crusts (BSCs) was very scarce. In 2011 and 2012, soil ecosystem covered by various types of BSCs and BSCs at different succession stages in an artificial sand-fixing vegetation region established in various periods at southeast of the Shapotou area in Tengger Desert was selected to measure fluxes of CO2, CH4 and N2O using static chamber and gas chromatography. The results showed that curst type, recovery time and their interactions with sampling date significantly affected CO2 flux. Recovery time and interaction of crust type and sampling date significantly affected CH4 flux. Sampling date significantly affected the fluxes of CO2, CH4 and N2O. The mean annual flux of CO2 for moss crust (105.1 mg x m(-2) x h(-1)) was significantly higher than that of algae crust (37.7 mg x m(-2) x h(-1)) at the same succession stage. Annual mean CH4 and N2O consumption was 19.9 and 3.4 microg x m(-2) x h(-1), respectively. Mean annual consumption of CH4 and N2O for algae crust was slightly higher than that of moss crust, however, significant difference was not found. Ecosystem respiration (Re) of desert soil covered by BSCs increased with the recovery process of desert ecosystem, in contrast, consumption of CH4 and N2O decreased. Re of moss crust was more sensitive to temperature and moisture variation than algae crust and Re sensitivity of temperature and moisture gradually increased with the development and succession of BSCs. Both soil temperature and moisture were not the main factor to determine CH4 and N2O fluxes of BSCs-soil in desert ecosystem.


Asunto(s)
Clima Desértico , Ecosistema , Gases/análisis , Suelo/química , Briófitas , Dióxido de Carbono/análisis , China , Metano/análisis , Óxido Nitroso/análisis , Dióxido de Silicio , Temperatura
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