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1.
Front Plant Sci ; 14: 1099250, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37235019

RESUMO

Zingiber zerumbet and Zingiber corallinum are economically valuable species in the genus Zingiber. While Z. corallinum is sexually active, Z. zerumbet adopts clonal propagation, although it has the potential for sexual reproduction. It is unclear so far at which step during the sexual reproduction of Z. zerumbet inhibition occurs, and what are the regulatory mechanisms underlying this inhibition. Here, by comparing with the fertile species Z. corallinum using microscopy-based methods, we show that rare differences were observed in Z. zerumbet up to the point when the pollen tubes invaded the ovules. However, a significantly higher percentage of ovules still contained intact pollen tubes 24 h after pollination, suggesting pollen tube rupture was impaired in this species. Further RNA-seq analysis generated accordant results, showing that the transcription of ANX and FER, as well as genes for the partners in the same complexes (e.g., BUPS and LRE, respectively), and those putative peptide signals (e.g., RALF34), were timely activated in Z. corallinum, which ensured the pollen tubes being able to grow, reorient to ovules, and receipt by embryo sacs. In Z. zerumbet, genes for these complexes were cooperatively suppressed, which would result in the maintenance of PT integrity due to the disruption of RALF34-ANX/BUPS signaling in PT and the failure of PT reception by an active synergid due to the insufficiency of the synergid-harbored FER/LRE complex. Taking the results from the cytological and RNA-seq studies together, a model is proposed to illustrate the possible regulation mechanisms in Z. zerumbet and Z. corallinum, in which the regulations for pollen tube rupture and reception are proposed as the barrier for sexual reproduction in Z. zerumbet.

2.
BMC Plant Biol ; 22(1): 407, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987603

RESUMO

BACKGROUND: The pollen ornate surface of flowering plants has long fascinated and puzzled evolutionary biologists for their variety. Each pollen grain is contained within a pollen wall consisting of intine and exine, over which the lipoid pollen coat lies. The cytology and molecular biology of the development of the intine and exine components of the pollen wall are relatively well characterised. However, little is known about the pollen coat, which confers species specificity. We demonstrate three types of pollen coat in Zingiberaceae, a mucilage-like pollen coat and a gum-like pollen coat, along with a pollen coat more typical of angiosperms. The morphological differences between the three types of pollen coat and the related molecular mechanisms of their formation were studied using an integrative approach of cytology, RNA-seq and positive selection analysis. RESULTS: Contrary to the 'typical' pollen coat, in ginger species with a mucilage-like (Caulokaempferia coenobialis, Cco) or gum-like (Hornstedtia hainanensis, Hhn) pollen coat, anther locular fluid was still present at the bicellular pollen (BCP) stage of development. Nevertheless, there were marked differences between these species: there were much lower levels of anther locular fluid in Hhn at the BCP stage and it contained less polysaccharide, but more lipid, than the locular fluid of Cco. The set of specific highly-expressed (SHE) genes in Cco was enriched in the 'polysaccharide metabolic process' annotation term, while 'fatty acid degradation' and 'metabolism of terpenoids and polyketides' were significantly enriched in SHE-Hhn. CONCLUSIONS: Our cytological and comparative transcriptome analysis showed that different types of pollen coat depend on the residual amount and composition of anther locular fluid at the BCP stage. The genes involved in 'polysaccharide metabolism' and 'transport' in the development of a mucilage-like pollen coat and in 'lipid metabolism' and 'transport' in the development of a gum-like pollen coat probably evolved under positive selection in both cases. We suggest that the shift from a typical pollen coat to a gum-like or mucilage-like pollen coat in flowering plants is an adaptation to habitats with high humidity and scarcity of pollinators.


Assuntos
Zingiberaceae , Aclimatação , Perfilação da Expressão Gênica , Lipídeos , Pólen , Zingiberaceae/genética
3.
BMC Plant Biol ; 21(1): 329, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238223

RESUMO

BACKGROUND: Rivers and streams facilitate movement of individuals and their genes across the landscape and are generally recognized as dispersal corridors for riparian plants. Nevertheless, some authors have reported directly contrasting results, which may be attributed to a complex mixture of factors, such as the mating system and dispersal mechanisms of propagules (seed and pollen), that make it difficult to predict the genetic diversity and population structure of riparian species. Here, we investigated a riparian self-fertilizing herb Caulokaempferia coenobialis, which does not use anemochory or zoochory for seed dispersal; such studies could contribute to an improved understanding of the effect of rivers or streams on population genetic diversity and structure in riparian plants. Using polymorphic ISSR and cpDNA loci, we studied the effect at a microgeographic scale of different stream systems (a linear stream, a dendritic stream, and complex transverse hydrological system) in subtropical monsoon forest on the genetic structure and connectivity of C. coenobialis populations across Dinghu Mountain (DH) and Nankun Mountain (NK). RESULTS: The results indicate that the most recent haplotypes (DH: H7, H8; NK: h6, h7, h11, h12) are not shared among local populations of C. coenobialis within each stream system. Furthermore, downstream local populations do not accumulate genetic diversity, whether in the linear streamside local populations across DH (H: 0.091 vs 0.136) or the dendritic streamside local populations across NK (H: 0.079 vs 0.112, 0.110). Our results show that the connectivity of local C. coenobialis populations across DH and NK can be attributed to historical gene flows, resulting in a lack of spatial genetic structure, despite self-fertilization. Selfing C. coenobialis can maintain high genetic diversity (H = 0.251; I = 0.382) through genetic differentiation (GST = 0.5915; FST = 0.663), which is intensified by local adaptation and neutral mutation and/or genetic drift in local populations at a microgeographic scale. CONCLUSION: We suggest that streams are not acting as corridors for dispersal of C. coenobialis, and conservation strategies for maintaining genetic diversity of selfing species should be focused on the protection of all habitat types, especially isolated fragments in ecosystem processes.


Assuntos
Biodiversidade , Fluxo Gênico , Variação Genética , Genética Populacional , Dispersão de Sementes/genética , Árvores/genética , China , Repetições de Microssatélites , Floresta Úmida , Clima Tropical , Áreas Alagadas
4.
Neural Regen Res ; 16(12): 2521-2527, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33907043

RESUMO

The expression of major histocompatibility complex class I (MHC-I), a key antigen-presenting protein, can be induced in dopaminergic neurons in the substantia nigra, thus indicating its possible involvement in the occurrence and development of Parkinson's disease. However, it remains unclear whether oxidative stress induces Parkinson's disease through the MHC-I pathway. In the present study, polymerase chain reaction and western blot assays were used to determine the expression of MHC-I in 1-methyl-4-phenylpyridinium (MPP+)-treated SH-SY5Y cells and a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease mouse model. The findings revealed that MHC-I was expressed in both models. To detect whether the expression of MHC-I was able to trigger the infiltration of cytotoxic T cells, immunofluorescence staining was used to detect cytotoxic cluster of differentiation 8 (CD8)+ T cell infiltration in the substantia nigra of MPTP-treated mice. The results indicated that the presentation of MHC-I in dopaminergic neurons was indeed accompanied by an increase in the number of CD8+ T cells. Moreover, in MPTP-induced Parkinson's disease model mice, the genetic knockdown of endogenous MHC-I, which was caused by injecting specific adenovirus into the substantia nigra, led to a significant reduction in CD8+ T cell infiltration and alleviated dopaminergic neuronal death. To further investigate the molecular mechanisms of oxidative stress-induced MHC-I presentation, the expression of PTEN-induced kinase 1 (PINK1) was silenced in MPP+-treated SH-SY5Y cells using specific small interfering RNA (siRNA), and there was more presentation of MHC-I in these cells compared with control siRNA-treated cells. Taken together, MPP+-/MPTP-induced oxidative stress can trigger MHC-I presentation and autoimmune activation, thus rendering dopaminergic neurons susceptible to immune cells and degeneration. This may be one of the mechanisms of oxidative stress-induced Parkinson's disease, and implies the potential neuroprotective role of PINK1 in oxidative stress-induced MHC-I presentation. All animal experiments were approved by the Southern Medical University Ethics Committee (No. 81802040, approved on February 25, 2018).

5.
Ecol Evol ; 10(14): 7792-7805, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32760565

RESUMO

The pattern of genetic differentiation between diverging species receives much attention as one of the key observable features of speciation. It has often been suggested that introgression between closely related species occurs commonly where their distributions overlap, leading to their becoming more morphologically and genetically similar, but there are a few opposite results. However, most of these studies have been carried out with animals and separate species; few have looked at intraspecific cases, especially in plants. Here, we conduct a comparative study on patterns of genetic differentiation among populations of two varieties of Oreocharis benthamii in allopatry and sympatry based on ISSR data for 754 individuals from 26 populations, in order to understand the processes leading to speciation. Contrary to expectations, the facultative xenogamy (mixed mating) species O. benthamii has a relatively low genetic diversity within populations (H = 0.1014, I = 0.1528) and high genetic differentiation among populations (G ST = 0.5867, ФST = 0.659), as is typically found for selfing species. Genetic variance between the two varieties in sympatric populations (44%, ФST = 0.444) is significantly more than that in allopatric populations (14%, ФST = 0.138). Consistent with the taxonomical delimitation of the two varieties, all sampled individuals of O. benthamii clustered into two genetic groups. Moreover, the genetic structures of populations of both varieties are correlated with their different geographical origins. Our studies show that significant divergence between sympatric populations of the two varieties could be attributed primarily to reinforcement by genetic divergent selection in sympatry where secondary contact had occurred. The major proportion of the genetic variation in outcrossing and mixed mating plants may exist among populations when the populations are distributed in fragmented habitats, due to the paucity of suitable habitat combined with inefficient seed dispersal mechanism and limited pollinator foraging area that may limit the gene flow.

6.
Arch Environ Contam Toxicol ; 78(4): 579-588, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32123946

RESUMO

The occurrence and potential sources of pharmaceuticals and personal care products (PPCPs) in surface waters from a large coastal city Qingdao, North China, were investigated. Forty-five compounds were analyzed by high-performance liquid chromatography-tandem mass spectrometry. The results showed that 28 compounds of PPCPs were detected. The most frequently detected compounds were atrazine, clarithromycin, nonylphenol, and bisphenol A with the detection rates > 90%. Paracetamol showed the highest concentration up to 4400 ng/L (mean 152.5 ng/L), followed by ampicillin (max. 2980 ng/L) with the highest mean concentration (229.3 ng/L), iopromide (max. 1744 ng/L, mean 74.5 ng/L), atrazine (max. 1612 ng/L, mean 96.1 ng/L), and bisphenol A (max. 1384 ng/L, mean 78.3 ng/L). The contamination levels and composition profiles of PPCPs along the rivers flowing through rural and urban areas and in seawater showed large spatial variability. Typical source markers and principle component analysis were used to track and differentiate the potential PPCP sources. The emphases of the study were the influence of animal farming in rural areas on PPCP composition profiles and the ecological risk. The results indicated that PPCPs in Qingdao surface water mainly came from three potential sources, i.e., treated wastewater (effluents from WWTPs), untreated wastewater, and nonpoint sources in agricultural areas.


Assuntos
Cosméticos/análise , Monitoramento Ambiental/métodos , Preparações Farmacêuticas/análise , Rios/química , Poluentes Químicos da Água/análise , Agricultura , China , Cidades , Medição de Risco , Água do Mar/química , Águas Residuárias/química
7.
Sci Rep ; 9(1): 17997, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784623

RESUMO

How mating system impacts the genetic diversity of plants has long fascinated and puzzled evolutionary biologists. Numerous studies have shown that self-fertilising plants have less genetic diversity at both the population and species levels than outcrossers. However, the phylogenetic relationships between species and correlated ecological traits have not been accounted for in these previous studies. Here, we conduct a comparative population genetic study of two closely related selfing and outcrossing Zingiber species, with sympatric distribution in Hainan Island, and obtain a result contrary to previous studies. The results indicate that selfing Z. corallinum can maintain high genetic diversity through differentiation intensified by local adaptation in populations across the species' range. In contrast, outcrossing Z. nudicarpum preserves high genetic diversity through gene exchange by frequent export of pollen within or among populations. Contrary to expectations, the major portion of genetic variation of outcrossing Z. nudicarpum may exist among populations, depending on the dispersal ability of pollen and seed. Our results also reveal that the main factor affecting population structure of selfing Z. corallinum is mountain ranges, followed by a moist climate, while that of outcrossing Z. nudicarpum is likely moisture, but not mountain ranges, due to gene flow via pollen.


Assuntos
Fluxo Gênico , Polinização/genética , Autofertilização/genética , Zingiberaceae/genética , Clima , Variação Genética , Genética Populacional , Ilhas , Filogenia
8.
Arch Environ Contam Toxicol ; 76(2): 255-264, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30390119

RESUMO

Surface waters from five districts in the inner city of Beijing were collected for analysis of 43 target compounds of pharmaceuticals and personal care products (PPCPs) to understand the spatial distribution patterns of different groups of PPCPs in the central urban area of a metropolitan city characterized by many hospitals and public parks. The total concentrations of PPCPs showed large spatial variability, ranging from 71.1 to 2400 ng/L. The x-ray contrast medium iopromide was the compound with the highest concentrations. Pharmaceuticals showed similar spatial distributional patterns with large hospitals. Positive correlations between iopromide and pharmaceuticals were observed. In contrast, in general there is no correlation between iopromide and personal care products. The concentrations of PPCPs in the landscape waters were not high but were characterized by high proportions of acidic, nonsteroidal anti-inflammatory drugs with low or even negative removal efficiencies in the WWTP in Beijing, suggesting that the reclaimed water irrigation can be another source of PPCPs in surface waters in the inner city of Beijing.


Assuntos
Irrigação Agrícola , Cosméticos/análise , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Hospitais
9.
J Transl Med ; 17(1): 433, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31888653

RESUMO

BACKGROUND: Gap junctions are involved in the development of cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH). However, the specific roles and regulatory functions of related connexin isoforms remain unknown. The aim of this study was to investigate the importance of connexin 43 (Cx43) in CVS and determine whether Cx43 alterations are modulated via the protein kinase C (PKC) signaling transduction pathway. METHODS: Oxyhemoglobin (OxyHb)-induced smooth muscle cells of basilar arterial and second-injection model in rat were used as CVS models in vitro and in vivo. In addition, dye transfer assays were used for gap junction-mediated intercellular communication (GJIC) observation in vitro and delayed cerebral ischemia (DCI) was observed in vivo by perfusion-weighted imaging (PWI) and intravital fluorescence microscopy. RESULTS: Increase in Cx43 mediated the development of SAH-induced CVS was found in both in vitro and in vivo CVS models. Enhanced GJIC was observed in vitro CVS model, this effect and increased Cx43 were reversed by preincubation with specific PKC inhibitors (chelerythrine or GF 109203X). DCI was observed in vivo on day 7 after SAH. However, DCI was attenuated by pretreatment with Cx43 siRNA or PKC inhibitors, and the increased Cx43 expression in vivo was also reversed by Cx43 siRNA or PKC inhibitors. CONCLUSIONS: These data provide strong evidence that Cx43 plays an important role in CVS and indicate that changes in Cx43 expression may be mediated by the PKC pathway. The current findings suggest that Cx43 and the PKC pathway are novel targets for developing treatments for SAH-induced CVS.


Assuntos
Conexina 43/metabolismo , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/metabolismo , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/metabolismo , Animais , Artéria Basilar/patologia , Células Cultivadas , Modelos Animais de Doenças , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Masculino , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Oxiemoglobinas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Inibidores de Proteínas Quinases/farmacologia , RNA Interferente Pequeno/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
10.
Bull Environ Contam Toxicol ; 101(5): 598-603, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30298274

RESUMO

The Yangtze River drainage basins are China's most important economic development zones and also the locations of several large-scale fluorine chemical industries. In order to reveal the contribution from the tributaries at the dividing point between the middle and lower reaches of the Yangtze River with respect to perfluorinated substances (PFASs), 17 PFAS compounds in surface water, groundwater, and tap water samples were analyzed in the tributary system of the Jiujiang section of the Yangtze River. The total concentrations of PFASs in the surface waters ranged from 7.8 to 586.2 ng/L. High proportion of short-chain compound PFBS in surface waters in Nanchang City, Poyang Lake, and the Yangtze River was observed which is likely of WWTPs' origin.


Assuntos
Monitoramento Ambiental/métodos , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , China , Cidades , Flúor/análise , Água Subterrânea/química , Lagos , Rios/química , Água
11.
Arch Environ Contam Toxicol ; 74(3): 484-491, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28965150

RESUMO

High levels of perfluoroalkyl substances (PFASs) were observed in rural areas near a fluorochemical industrial park (FCIP) in the Yangtze River Delta region. The concentrations of total PFAS (∑PFASs) in soil, surface water, groundwater, and rainwater were in the range of 0.6-64.6 ng/g dry weight, 15.6-480.9, 4.8-614.6, and 13.4-542.2 ng/L, respectively. PFASs in rainwater and groundwater were higher than in surface water. The influence of the FCIP on rural soils extended to a distance of approximately 4 km based on the changes in PFAS compositions. The impact on surface water is mainly through direct river flow connected with contaminated sources, which may extend farther than 7 km in the case of unrestricted flow but much shorter distance for unconnected rivers. The penetration of PFASs in groundwater aquifers can extend as far as ca. 6 km, while direct water flow is the main transport route for PFASs. The influence radius of the FCIP can be as far as 60 km due to atmospheric precipitation.


Assuntos
Indústria Química , Fluorocarbonos/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , China , Meio Ambiente , Monitoramento Ambiental , Água Subterrânea/química
12.
Chemosphere ; 185: 610-617, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28719881

RESUMO

Perfluoroalkyl acids (PFAAs) are widely used as multi-purpose surfactants or water/oil repellents. In order to understand the contamination level and compositional profiles of PFAAs in aqueous environment in textile, leather, and paper making industrial areas, surface waters and tap waters were collected along the watershed of the Qiantang River where China's largest textile, leather, and paper making industrial bases are located. For comparison, surface water and tapwater samples were also collected in Hangzhou and its adjacent areas. 17 PFAAs were analyzed by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. The results show that the total concentrations of PFAAs (ΣPFAAs) in the Qiantang River waters ranged from 106.1 to 322.9 ng/L, averaging 164.2 ng/L. The contamination levels have been found to be extremely high, comparable to the levels of the most serious PFAA contamination in surface waters of China. The PFAA composition profiles were characterized by the dominant PFOA (average 58.1% of the total PFAAs), and PFHxA (average 18.8%). The ΣPFAAs in tap water ranged from 9.5 to 174.8 ng/L, showing PFAA compositional pattern similar to the surface waters. Good correlations between PFAA composition profiles in tap waters and the surface waters were observed.


Assuntos
Água Potável/química , Monitoramento Ambiental , Fluorocarbonos/análise , Curtume/estatística & dados numéricos , Indústria Têxtil/estatística & dados numéricos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , China , Água Doce/química , Indústrias , Papel , Rios/química , Extração em Fase Sólida , Tensoativos/análise , Têxteis/análise , Águas Residuárias/estatística & dados numéricos , Água/análise
13.
Bull Environ Contam Toxicol ; 99(2): 224-231, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28528484

RESUMO

The contamination status of perfluoroalkyl substances (PFASs) were investigated in 64 tapwater samples collected from 17 cities and 45 surface water samples from adjacent areas in the eastern China. The total PFAS concentrations in tapwater ranged from 1.4 to 175 ng/L; relatively higher PFAS levels were observed in samples collected from the Yangtze River Delta region, which was similar to the geographical distribution pattern of PFAS levels observed in rivers and lakes. The highest total PFASs in tapwater was found in Changshu, where several fluorine-related industries are located, whereas the lowest was observed in Beijing. Significant positive correlations between PFAS compositions in tap water sample and their source waters were noted. Several industries such as paper, textile, and leather industries may contribute to the contamination of PFASs in tapwater.


Assuntos
Água Potável/química , Monitoramento Ambiental , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Pequim , Caprilatos , China , Cidades , Fluoretos/análise , Flúor/análise , Lagos , Rios , Água
14.
Environ Pollut ; 211: 124-31, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26745397

RESUMO

Little research on perfluorinated compounds (PFCs) has been conducted in rural areas, although rural PFC sources are less complicated than in urban and industrial areas. To determine the levels and geographical distribution of 17 PFC compounds, samples of soil, surface water, and groundwater were collected from eight rural areas in eastern China. The total PFC concentrations (∑PFCs) in soils ranged from 0.34 to 65.8 ng/g ∑PFCs in surface waters ranged from 7.0 to 489 ng/L and ∑PFCs in groundwater ranged from 5.3 to 615 ng/L. Ratios of perfluorononanoic acid/perfluorooctanoic acid (PFNA/PFOA), perfluoro-n-butyric acid/perfluorooctanoic acid (PFBA/PFOA), and perfluoroheptanoic acid/perfluorooctanoic acid (PFHpA/PFOA) in rainwater increased due to the fluorine chemical plants in the surrounding rural and urban areas, suggesting that atmospheric precipitation may carry PFCs and their precursors from the fluorochemical industrial area to the adjacent rural areas.


Assuntos
Fluorocarbonos/análise , Água Doce/química , Água Subterrânea/química , Solo/química , Poluentes Químicos da Água/análise , Caprilatos/análise , China , Monitoramento Ambiental , Indústrias
15.
Ecol Evol ; 5(22): 5364-5371, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30151138

RESUMO

Flexistyly in Plagiostachys was first reported by Takano et al., while they provided no detailed study on pollination biology and breeding system. In this study, we tested this suspicion in one species of Plagiostachys (Plagiostachys austrosinensis). Field observations suggested that flexistyly was present in this species, and stigmatic behavior was similar to that reported for Alpinia and Amomum species. Two phenotypes (anaflexistylous and cataflexistylous) occurred in a ratio of 1:1 in natural populations. Anthesis began around 1530-1600 h and lasted for about 24 h. Pollen viability and stigma receptivity remained high throughout the flowering process. Mean nectar volume (4.15-11.30 µL) and mean sugar concentration (>32%) also remained at a high level during the flowering process. No fruit set occurred in unpollinated bagged plants. Two pollinators (Bombus pyrosoma and Vespidae spp.) and one pollen robber (Mutillidae spp.) were found as flower visitors. Fruit set following self-pollination and cross-pollination did not differ significantly in the cataflexistylous morph. Partial self-incompatibility was apparent in the anaflexistylous morph. These results provide the concrete evidence of flexistyly in Plagiostachys and a more thorough understanding of its evolutionary origin in gingers.

16.
Neurosci Lett ; 541: 77-82, 2013 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-23523648

RESUMO

Research in mesenchymal stem cells (MSCs) is mainly focused on applications for treatments of brain and spinal cord injury as well as mechanisms underlying effects of MSCs. However, due to numerous limitations, there is little information on selection of appropriate sources of MSCs for transplantation in clinical applications. Therefore, in this study we compared various properties of human umbilical cord-derived MSCs (HUCMSCs) with human placenta-derived MSCs (HPDMSCs), including cell proliferation, apoptosis, cellular morphology, ultrastructure, and their ability to secrete various growth factors (i.e. vascular endothelial growth factor, insulin-like growth factors-1, and hepatocyte growth factor), which will allow us to select appropriate MSC sources for cellular therapy. Cell culture, flow cytometry, transmission electron microscope (TEM) and atomic force microscope (AFM) were used for assessment of HUCMSCs and HPDMSCs. Results showed that the two types of cells appeared slightly different when they were observed under AFM. HUCMSCs appeared more fibroblast-like, whereas HPDMSCs appeared as large flat cells. HUCMSCs had higher proliferative rate and lower rate of apoptosis than HPDMSCs (p<0.05). However, HPDMSCs secreted more of the three growth factors than HUCMSCs (p<0.05). Results of TEM revealed that the two types of MSCs underwent active metabolism and had low degree of differentiation, especially HUCMSCs. Results of AFM showed that HUCMSCs had stronger ability of mass transport and cell migration than HPDMSCs. However, HPDMSCs displayed stronger adhesive properties than HUCMSCs. Our findings indicate that different sources of MSCs have different properties, and that care should be taken when choosing the appropriate sources of MSCs for stem cell transplantation.


Assuntos
Apoptose , Proliferação de Células , Células Endoteliais da Veia Umbilical Humana/citologia , Células-Tronco Mesenquimais/citologia , Placenta/citologia , Adulto , Feminino , Células Endoteliais da Veia Umbilical Humana/ultraestrutura , Humanos , Células-Tronco Mesenquimais/ultraestrutura , Gravidez , Cultura Primária de Células
17.
J Neurooncol ; 112(3): 339-45, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23417321

RESUMO

A previous report has confirmed the existence and clinical significance of vasculogenic mimicry (VM) in glioma. However, its conclusions about the negative clinical significance of VM in glioblastoma are based on a small group of patients and, thus, might be unconvincing. The aim of the present study was to reevaluate the clinical significance of VM in glioblastoma. Patients were classified as VM-positive or VM-negative according to CD34 and periodic acid-Schiff staining. The association between VM and the clinical characteristics of the patients was analyzed. Univariate and multivariate analyses were carried out to identify the independent prognostic factors for overall survival using the Cox regression hazard model. Survival times were estimated using the Kaplan-Meier method and compared using the log-rank test. Of all 86 glioblastomas, 23 were found to have VM. The presence of VM in glioblastoma was not associated with gender, age, Karnofsky performance status, hydrocephalus, tumor burden, microvessel density, tumor relapse, or the extent of tumor resection. The univariate and multivariate analyses revealed that VM is an independent prognostic factor for overall survival. The median survival time for patients with VM was 11.17 months compared with 16.10 months for those without VM (P = 0.017). In addition to VM, an age of 65 years or older, a KPS of 60 or less, a large tumor burden are significant prognostic factors for patient survival. Our data suggest that VM might be an independent adverse prognostic factor in newly diagnosed GBM, further prospective studies are needed to answer this question.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Glioblastoma/irrigação sanguínea , Glioblastoma/patologia , Adolescente , Adulto , Idoso , Antígenos CD34/análise , Antígenos CD34/biossíntese , Neoplasias Encefálicas/mortalidade , Feminino , Glioblastoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Adulto Jovem
18.
Orthopedics ; 35(9): 779-88, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22955387

RESUMO

Mesenchymal stem cells (MSCs) have been isolated from a variety of human tissues (eg, bone marrow, peripheral blood, muscle, fat, umbilical blood, amniotic fluid, embryonic tissues, and placenta). Placenta-derived MSCs (PDMSCs) have received considerable interest because of their wide availability and absence of ethical concerns. The authors characterized the biological properties, ultrastructure, growth factor production, and osteoblastic differentiation of PDMSCs and investigated their potential as seed cells for bone tissue engineering.


Assuntos
Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/imunologia , Osteoblastos/citologia , Osteoblastos/imunologia , Osteogênese/imunologia , Engenharia Tecidual/métodos , Técnicas de Cultura Celular por Lotes/métodos , Diferenciação Celular/imunologia , Proliferação de Células , Células Cultivadas , Estudos de Viabilidade , Feminino , Humanos , Projetos Piloto , Placenta , Gravidez
19.
Neuroreport ; 23(8): 513-8, 2012 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-22525837

RESUMO

Human placental decidua basalis-derived mesenchymal stem cells (DBMSCs) have been identified as valuable sources for cell transplantation. In this study, we found that DBMSCs could be induced to form neural stem cells in the form of neurospheres. These neurospheres were further differentiated into dopamine neuron-like cells with a cocktail of cytokines. The differentiated DBMSCs were verified through the presence of a neuron-like morphology, the expression of specific dopamine neuron makers, and the production of dopamine. In addition, this differentiation capacity of DBMSCs was not affected by long-term culture, and the cells maintained a normal karyotype in vitro. The dopamine neuronal differentiation and the relative safety transplantation potential of DBMSCs may facilitate stem cell therapeutic approaches to Parkinson's disease.


Assuntos
Diferenciação Celular/fisiologia , Decídua/citologia , Neurônios Dopaminérgicos/fisiologia , Células-Tronco Mesenquimais/citologia , Antígenos CD/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Dopamina/metabolismo , Feminino , Humanos , Recém-Nascido , Cariotipagem , Masculino , Proteínas do Tecido Nervoso/metabolismo , Gravidez
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(2): 262-5, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21354907

RESUMO

OBJECTIVE: To investigate the biological features of human decidua basalis-derived mesenchymal stem cells (PDB-MSCs) in vitro and identify their capacity of multilineage differentiation. METHODS: PDB-MSCs were harvested from the decidua basalis of term placental by enzymatic digestion and density gradient centrifugation, and the growth characteristics and morphological changes of the MSCs were observed by inverted microscope. The proliferative ability of the cells was assessed by Cell Counting Kit-8. The cell cycle and expressions of the surface markers (CD29, CD44, CD73, CD90, CD34, CD45, and CD14) of the MSCs were identified by flow cytometry. Multilineage differentiation capacity of the cells was tested by inducing their differentiation toward osteoblasts, adipocytes and chondroblasts in vitro. RESULTS: MSCs isolated from human decidua basalis of term placental exhibited a morphology similar to that of bone marrow-derived MSCs, and grew into colonies in in vitro culture, where the cells proliferated rapidly after passage with a cell doubling time of 2.21∓0.21 days. More than 70% of the cells stayed in the resting stage (G(0)/G(1)) and showed positivity for CD29, CD44, CD73 and CD90, but not for CD14, CD34 or CD45. After induction, the cells showed positive results of alizarin red staining, oil red O staining and Alcian blue staining. CONCLUSION: Human decidua basalis contains a rich source of MSCs, which can be easily isolated and cultured without affecting their capacity of multilineage differentiation. The PDB-MSCs may have the potential as a novel source of stem cells.


Assuntos
Diferenciação Celular/fisiologia , Decídua/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Separação Celular , Células Cultivadas , Feminino , Humanos , Placenta/citologia , Gravidez
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