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1.
Am J Bot ; 105(1): 42-49, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29532922

RESUMO

PREMISE OF THE STUDY: The growth limitation hypothesis (GLH) and carbon limitation hypothesis (CLH) are two dominant explanations for treeline formation. The GLH proposes that low temperature drives the treeline through constraining C sinks more than C sources, and it predicts that non-structural carbohydrate (NSC) levels are static or increase with elevation. Although the GLH has received strong support globally for evergreen treelines, there is still no consensus for deciduous treelines, which experience great asynchrony between supply and demand throughout the year. METHODS: We investigated growth and the growing-season C dynamics in a common deciduous species, Erman's birch (Betula ermanii), along an elevational gradient from the closed forest to the treeline on Changbai Mountain, Northeast China. Samples were collected from developing organs (leaves and twigs) and main storage organs (stems and roots) for NSC analysis. KEY RESULTS: Tree growth decreased with increasing elevation, and NSC concentrations differed significantly among elevations, organs, and sampling times. In particular, NSC levels varied slightly during the growing season in leaves, peaked in the middle of the growing season in twigs and stems, and increased continuously throughout the growing season in roots. NSCs also tended to increase or vary slightly in developing organs but decreased significantly in mature organs with increasing elevation. CONCLUSIONS: The decrease in NSCs with elevation in main storage organs indicates support for the CLH, while the increasing or static trends in new developing organs indicate support for the GLH. Our results suggest that the growth limitation theory may be less applicable to deciduous species' growth than to that of evergreen species.


Assuntos
Betula/crescimento & desenvolvimento , Betula/metabolismo , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Altitude , Metabolismo dos Carboidratos , Carbono/metabolismo , China , Estações do Ano
2.
Exp Ther Med ; 13(1): 23-28, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28123462

RESUMO

The aim of the present study was to establish an immunofluorescence method of antibody detection to identify melanocytes in the serum of vitiligo patients. Furthermore, we aimed to establish a method for the culture and proliferation of autologous pure melanocytes and to observe the effect of their transplantation for the treatment of vitiligo. Suspension of epidermal cells with melanocytes was performed using trypsin digestion of normal epiderm from eyelid operation and melanocytes were selectively cultured and proliferated in serum-free M2 medium. FITC-labeled rabbit anti-human antibody was used to detect the relative fluorescence intensity of the melanocytes. After identification with immunological and biological examinations, the melanocytes were transplanted to depigmented areas of vitiligo. Repigmentation was observed continuously. The results indicated that melanocytes could be selectively proliferated in the medium. Subsequently, pure melanocytes without contamination of fibroblast and keratinocyte were harvested. A total of 34 patients suffering vitiligo for between 3 months and 20 years with depigmented area (between 4 cm2 and 70% of body surface) were divided into 19 cases of developing stage and 15 cases of stable stage, according to the change of depigmentation. A total of 15 developing cases were positive for the antibody against melanocytes, with the positive rate of 79%. The titers of serum was >1:50 in 10 patients at the developing stage, and 5 developing patients were 1:10. Among the 15 stable cases, four were positive, with a positive rate of 27%. Fluorescence of antibody was localized in the cytoplasm of the melanocytes. Autologous melanocytes of vitiligo patients could be selectively proliferated in the medium. Next, pure melanocytes without contamination with fibroblasts and keratinocytes were harvested. A total of 16 vitiligo patients with 28 depigmented areas (2-200 cm2) were treated with transplantation of melanocytes. Repigmentation of the transplanted areas appeared as red coloration after one month. All the vitiligous areas received transplantation were repigmented significantly with hypo- or hyper-pigmentation after 3-5 months. After 6-8 months, 87.5% of lesions showed repigmentation of >50% of the lesion area. No scarring or other side-effects occurred. After follow-up of 5 years, no relapse was observed in transplantation area. Thus, an immunofluorescence method for the test of antibody to melanocytes in the serum of vitiligo patients was established. Transplantation of cultured autologous melanocytes was an effective and safe measure for treatment of vitiligo, particularly for patients with a large depigmented area.

3.
Funct Plant Biol ; 44(3): 302-311, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32480565

RESUMO

Drought and salinity are the two most common and frequently co-occurring abiotic stresses limiting plant productivity worldwide, yet it remains unclear whether bamboo species possess effective mechanisms to protect against oxidative damage caused by drought and salinity, either alone or in combination. In this study, we utilised Fargesia rufa Yi, a species important to forest carbon sequestration and endangered giant pandas, to evaluate physiological, biochemical and ultrastructural responses to drought, salinity and their combination. Under drought alone, F. rufa exhibited reduced water loss from leaves, photochemistry inhibition, pigment degradation, reactive oxygen species accumulation, lipid peroxidation, and damage to organelles compared with salinity and combined stress treatments. The superior performance under drought alone was attributed to greater thermal dissipation and the water-water cycle capacities, increased SOD/AsA-GSH cycle enzymes activities, and a favourable redox balance of antioxidants. Therefore, relative to salinity alone and drought+salinity, F. rufa plants under drought exhibit highly efficient mechanisms to protect against oxidative damage, which most likely allow accelerated recovery of photosynthetic plasticity once the stress is removed.

5.
Arthroscopy ; 31(11): 2224-31, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26051353

RESUMO

PURPOSE: To summarize the clinical findings of adult patients undergoing arthroscopy-assisted open reduction-internal fixation for acute ankle fractures. METHODS: A systematic electronic search of the PubMed databases was performed for all published literature on December 8, 2014. All English-language clinical studies on acute ankle fractures treated with arthroscopy-assisted open reduction-internal fixation were eligible for inclusion. Basic information related to the surgical procedure was collected. RESULTS: The search criteria initially identified 187 articles, and 10 studies were included in this systematic review. There were 2 prospective, randomized studies; 2 prognostic studies; and 6 case-series studies. There were a total of 861 patients included in this systematic review. Danis-Weber type B fractures (335 of 483 patients) and supination-external rotation fractures (187 of 366 patients) were the most common types of all the ankle fractures. Concomitant injuries were common: 63.3% of patients had chondral lesions, 60.9% had deltoid ligament injuries, and 77.9% had tibiofibular syndesmosis injuries. Lavage and debridement of the ankle joint were performed by almost all the surgeons. Chondral lesions were treated with shaving, excision, or microfracture. The mean American Orthopaedic Foot & Ankle Society hindfoot score was 91.7. Only mild complications were reported. CONCLUSIONS: Acute ankle fractures are commonly concomitant with multiple soft-tissue injuries in which arthroscopy may serve as a method for accurate diagnosis and appropriate treatment. LEVEL OF EVIDENCE: Level IV, systematic review of Level I, II, III, and IV studies.


Assuntos
Fraturas do Tornozelo/cirurgia , Articulação do Tornozelo/cirurgia , Artroscopia/métodos , Fixação de Fratura/métodos , Cirurgia Assistida por Computador/métodos , Fixação Interna de Fraturas/métodos , Humanos
6.
Arthroscopy ; 31(1): 143-53, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25125382

RESUMO

PURPOSE: This study aimed to summarize the recent clinical outcomes of patients undergoing arthroscopy-assisted reduction and internal fixation (ARIF) for tibial plateau fractures. METHODS: A systematic electronic search of the PubMed and Cochrane databases was performed in January 2014. All English-language clinical studies on tibial plateau fractures treated with ARIF that were published after January 1, 2000 were eligible for inclusion. Basic information related to the surgery was collected. RESULTS: The search criteria initially identified 141 articles, and 19 studies were included in this systematic review. There were 2 retrospective comparative studies, 16 case series studies, and one clinical series based on a technique note. There were a total of 609 patients in this systematic review, with a mean follow-up time of 52.5 months. The most common fracture types were Schatzker types II and III. Concomitant injuries were common: 42.2% of the patients had meniscal injuries, and 21.3% had anterior cruciate ligament (ACL) injuries. In addition, the status of 90.5% of the patients was classified as good or excellent according to the clinical Rasmussen scoring system, and 90.9% of the patients were satisfied with the treatment. Only 6 severe complications were reported, including one case of compartment syndrome. CONCLUSIONS: ARIF is a reliable, effective, and safe method for the treatment of tibial plateau fractures, especially when they present with concomitant injuries. LEVEL OF EVIDENCE: Level IV, systematic review of Level III and Level IV studies.


Assuntos
Artroscopia/métodos , Fraturas da Tíbia/cirurgia , Adulto , Lesões do Ligamento Cruzado Anterior , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Traumatismos do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Lesões dos Tecidos Moles/cirurgia , Lesões do Menisco Tibial , Adulto Jovem
7.
Huan Jing Ke Xue ; 35(2): 547-54, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24812946

RESUMO

Antimony has been ubiquitously present in the aquatic environment as a toxic and rare metalloid element. The contamination of antimony and its compounds in the environment is increasingly severe, so it has been received extensive attention by the international scientific community. The cruise was carried out in the coastal area of Zhejiang and Fujian provinces in the East China Sea (ECS) in May 2008. The concentrations of total dissolved inorganic antimony (TDISb) were measured by Hydride Generation-Atomic Fluorescence (HG-AFS). The concentration ranges of TDISb in the surface and bottom layer were 0.68-5.64 nmol x L(-1) and 0.71-5.25 nmol x L(-1) with averages of 2.25 and 1.79 nmol x L(-1), respectively. The concentration of TDISb in the study area was lower than the environmental quality standards for surface water of China and drinking water standards of World Health Organization (about 41.08 nmol x L(-1)), indicating that it remained at the pristine level. The concentration of TDISb decreased gradually from the coastal area to the central ECS shelf with higher concentration in the surface layer than the bottom. Water mass mixing, adsorption/desorption behavior on the surface of the suspended particulate matters (SPM) and biological activities were the main influence factors of TDISb biogeochemistry in the study area.


Assuntos
Antimônio/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Adsorção , China , Poluentes Ambientais/normas
8.
Biol Pharm Bull ; 36(11): 1700-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24189414

RESUMO

Metabolomics is a new platform based on the comprehensive analysis of low molecular weight metabolites and provides a powerful approach to discover biomarkers in biological systems. Modified Sinisan (MSNS), a traditional Chinese medicine formula, displayed bright prospects in the prevention and therapy of liver injury. However, its molecular mechanism of hepatoprotective effects remains unclear. This paper was designed to explore the effects and potential mechanisms of MSNS against dimethylnitrosamine-induced liver injury. Global metabolic profiling was performed by ultra-performance liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC/ESI-Q-TOF-MS) in conjunction with multivariate data analysis and pathway analysis. Eleven serum biomarkers were identified and pathway analysis results showed that phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, tryptophan metabolism, retinol metabolism, tyrosine metabolism were perturbed by liver injury. More importantly, MSNS has showed satisfactory pharmacological effect on liver injury through partially regulating the perturbed pathways, correlates well to the biochemical and histopathological detection results. The present study proved that the robust metabolomics approach is promising for unraveling hepatoprotective effects of MSNS and these findings provide new insights into mechanisms of the liver injury, and its pathophysiologic processes.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/sangue , Medicamentos de Ervas Chinesas/farmacologia , Substâncias Protetoras/farmacologia , Animais , Biomarcadores/sangue , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/patologia , Dimetilnitrosamina , Medicamentos de Ervas Chinesas/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Metabolômica , Fitoterapia , Substâncias Protetoras/uso terapêutico , Ratos , Ratos Wistar
9.
Ying Yong Sheng Tai Xue Bao ; 24(8): 2310-8, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24380353

RESUMO

An investigation was made on the abundance and biomass of planktonic ciliates in the shelf of East China Sea in May (spring) and November (autumn), 2011. The abundance of the ciliates in spring and autumn was averagely (614 +/- 861) and (934 +/- 809) ind x L(-1), and the biomass was averagely (1.70 +/- 3.91) and (0.93 +/- 0.99) microg C x L(-1), respectively. The high abundance and biomass in spring were found in coastal and offshore areas, and those in autumn were in offshore only. In the two seasons, the ciliates tended to accumulate in the waters upper layer, and sometimes flocked in the bottom. In the spring, aloricate ciliate species were larger than those in the autumn. Tintinnids occupied (26.9% +/- 34.3)% and (44.9% +/- 25.2)% of the total ciliates abundance in spring and autumn, respectively. In taxonomy, 52 tintinnid species of 27 genera were identified. The most dominant species were Tintinnidium primitivum, Stenosemella oliva, and Tintinnopsis tubulosoides in spring, and Tintinnidium primitivum, Stenosemella parvicollis, and Tintinnopsis nana in autumn. The ciliates abundance showed significant positive correlations with water temperature and Chl a concentration, the tintinnids abundance showed significant negative correlation with water salinity, and the tintinnids community was significantly related to water temperature.


Assuntos
Cilióforos/crescimento & desenvolvimento , Zooplâncton/crescimento & desenvolvimento , Animais , Biomassa , China , Cilióforos/classificação , Ecossistema , Oceanos e Mares , Estações do Ano , Zooplâncton/classificação
10.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 21(5): 565-9, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16143058

RESUMO

AIM: To construct a mutant of human tissue plasminogen activator (t-PA) with activity not inhibited by plasminogen activator inhibitor-1 (PAI-1). METHODS: The finger, epidermal growth factor and kringle-1 domains were removed from native t-PA to obtain a t-PA mutant with the PAI-1 binding sites. A pUC18 plasmid containing the human t-PA full-length cDNA sequence was used as template, and the DNA sequences encoding 1-3 and 176-527 amino acids were amplified by PCR. The nucleotides AAG CAC AGG AGG (from 373 to 384) in the PAI-1 binding site changed to GCG GCC GCG GCG, so amino acid KHRR was replaced by AAAA correspondently. RESULTS: Sequencing result showed that the above t-PA mutant DNA sequence was consistent with the expected. Then it was cloned in an E.coli expression vector and was highly expressed. The expressed protein occupied about 30% of total bacterial proteins as inclusion body. After denaturation and renaturation, the active t-PA mutant was obtained,activity of which was not inhibited by PAI-1. CONCLUSION: This t-PA mutant may be developed to a new gene-engineering drug with higher therapeutic activity and lower dose requirement in the treatment of acute myocardial infarction and cerebrovascular thrombosis diseases.


Assuntos
Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tecidual/metabolismo , Sítios de Ligação/genética , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Humanos , Reação em Cadeia da Polimerase , Ligação Proteica/genética , Ativador de Plasminogênio Tecidual/isolamento & purificação
11.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 21(4): 456-8, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15989790

RESUMO

AIM: To express DnaJ-homologous chaperon peripherin-binding protein(PBP) gene in E.coli and prepare the rabbit antibody against PBP. METHODS: The PBP cDNA was amplified from the human fetal brain tissue by RT-PCR. After confirmed by DNA sequencing, the PBP-cDNA was cloned into expression vector pET28a and then the PBP gene was expressed in E.coli under the IPTG induction. The expressed protein was purified through Ni-NTA affinity chromatography column. The rabbit antibody against PBP was prepared by immunizing two New Zealand white rabbits using the purified PBP as immunogen. The titer and specificity of the antisera were determined by Western blot. RESULTS: The 720 bp PBP gene was amplified, cloned, and expressed in E.coli. The expressed product existed in the bacterial inclusion body and the supernatant of the bacteria lysate. The purified PBP reached electrophoretic purity. The rabbit antibody against PBP was prepared and its titer was about 1:1,600. Western blot analysis showed that the antibody could bind to the expressed PBP protein specifically. CONCLUSION: The PBP protein was expressed in E.coli and rabbit antibody against PBP was prepared successfully, which lays the foundation for further study on the structure and biological function of PBP.


Assuntos
Anticorpos Antibacterianos/imunologia , Escherichia coli/genética , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/imunologia , Animais , Especificidade de Anticorpos , Clonagem Molecular , DNA Complementar/genética , Eletroforese em Gel de Poliacrilamida , Escherichia coli/citologia , Expressão Gênica , Vetores Genéticos/genética , Proteínas de Choque Térmico HSP40/biossíntese , Proteínas de Choque Térmico HSP40/isolamento & purificação , Humanos , Corpos de Inclusão , Coelhos
12.
Space Med Med Eng (Beijing) ; 17(3): 162-5, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15920839

RESUMO

OBJECTIVE: To observe the effects of different levels of acute +Gz exposure on myocardial ultrastructure of rats and provide experimental basis for further development of anti-G measures. METHOD: Twenty male Wistar rats were randomly divided into 4 groups (n=5): normal control group, +20 Gz group, +10 Gz group and +5 Gz group. Profile of the centrifuge +Gz exposure was trapezoidal, in which +20 Gz lasted for 30 s, +10 Gz for 1.5 min. +5 Gz exposure was repeated for 3 times with 30 min interval and each for 1.5 min. Myocardial tissue of left ventricle was sampled for transmission electron microscopy 5 h after exposure. RESULT: +20 Gz and +10 Gz exposure caused obvious edema of myocardial and endothelial cells, myofibril disorder and injuries of mitochondria and nucleus. Breaks of myocardial fiber, formation of contraction bands and rupture of mitochondria were also observed in +20 Gz group. In +5 Gz group, there was still slight edema of myocardial and endothelial cells, while organic changes of myocardial ultrastructure were not observed. CONCLUSION: High +Gz exposure can cause myocardial ultrastructural injury in rats. Slight reversible injured response can also be observed in myocardial cell after repeated moderate level of +Gz exposure. This indicates that attention should be paid to the study of the effect of high +Gz on heart in pilots.


Assuntos
Células Endoteliais/ultraestrutura , Hipergravidade/efeitos adversos , Miocárdio/ultraestrutura , Aceleração , Animais , Núcleo Celular/ultraestrutura , Centrifugação , Líquido Intracelular/fisiologia , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Miocárdio/citologia , Miofibrilas/ultraestrutura , Ratos , Ratos Wistar
13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 19(6): 531-4, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15182641

RESUMO

AIM: To isolate and identify a human DnaJ homolog chaperon, PBP, from a human skeleton cDNA library, and to analyze its expression and distribution in transfected mammalian cells. METHODS: (32)p-dCTP labeled probe hybridization was used to screen the human skeleton cDNA library and sequence of the positive clones were analyzed. Then PBP gene was transfected into COS-7 cells using lipofectamin. PBP expressed in the cells were detected by Western-blot and indirect immunofluorescence staining. RESULTS: A full-length(1.5 kb) cDNA of peripherin-binding protein (PBP) was identified, which is identical with that of mrj. Full length PBP was mainly localized to cytoplasms of COS-7 cells in interphase, and to nuclei in mitosis. CONCLUSION: The results indicate that besides cooperating with DnaK (HSP70), PBP itself plays an important role as a member of DnaJ family. PBP may also be involved in the regulation of cell cycle.


Assuntos
Proteínas de Transporte/genética , Proteínas de Choque Térmico/genética , Proteínas de Filamentos Intermediários/metabolismo , Glicoproteínas de Membrana/metabolismo , Chaperonas Moleculares/genética , Proteínas do Tecido Nervoso/metabolismo , Sequência de Aminoácidos , Animais , Células CHO , Células COS , Proteínas de Transporte/análise , Proteínas de Transporte/fisiologia , Clonagem Molecular , Cricetinae , Proteínas de Choque Térmico HSP40 , Proteínas de Choque Térmico/análise , Proteínas de Choque Térmico/fisiologia , Chaperonas Moleculares/análise , Dados de Sequência Molecular , Periferinas
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