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1.
Cell Mol Life Sci ; 80(9): 257, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37594573

RESUMEN

Severe acute pancreatitis (SAP) is a common critical disease of the digestive system, with high mortality and a lack of effective prevention and treatment measures. Despite mesenchymal stromal cell transplantation having the potential to treat SAP, its clinical application prospect is limited, and the mechanism is unclear. Here, we reveal the therapeutic role of exosomes from TNF-α-preconditioned human umbilical cord mesenchymal stromal cells (HUCMSCs) in attenuating SAP and show that it is partly dependent on exosomal metabolites. Bioactive metabolomics analysis showed that 48 metabolites be significantly differentially expressed between the two groups (Exo-Ctrl group versus Exo-TNF-α group). Then, the further functional experiments indicated that 3,4-dihydroxyphenylglycol could be a key molecule mediating the therapeutic effect of TNF-α-preconditioned HUCMSCs. The animal experiments showed that 3,4-dihydroxyphenylglycol reduced inflammation and oxidative stress in the pancreatic tissue and inhibited acinar cell autophagy in a rat model of SAP. Mechanistically, we revealed that 3,4-dihydroxyphenylglycol activated the mTOR pathway to inhibit acinar cell autophagy and alleviate SAP. In summary, our study demonstrated that exosomes from TNF-α-preconditioned HUMSCs inhibit the autophagy of acinar cells of SAP by shuttling 3,4-dihydroxyphenylglycol and inhibiting the mTOR pathway. This study revealed the vital role and therapeutic potential of metabolite-derived exosomes in SAP, providing a new promising method to prevent and therapy SAP.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , Pancreatitis , Humanos , Animales , Ratas , Pancreatitis/terapia , Células Acinares , Factor de Necrosis Tumoral alfa , Enfermedad Aguda , Autofagia , Serina-Treonina Quinasas TOR , Cordón Umbilical
2.
J Asian Nat Prod Res ; 25(4): 324-329, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35763403

RESUMEN

Two new iridoid glycosides, named 3'-O-benzoyl-dolichocymboside D (1) and dolichocymboside E (2), along with ten known glycosides (3-12), were isolated from the ethanol extract of the whole plants of Odontites vulgaris Moench. The structures of the isolated compounds were elucidated by 1D and 2D NMR and HR-ESI-MS spectra and by comparison with those reported in the literature. This is the first report on compounds 11 and 12 isolated from the family Scrophulariaceae, and compounds 8-10 were isolated from the genus Odontites.


Asunto(s)
Glicósidos Iridoides , Extractos Vegetales , Glicósidos Iridoides/química , Extractos Vegetales/química , Glicósidos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
3.
Mol Cell Biochem ; 477(12): 2761-2771, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35622186

RESUMEN

To investigate whether bone marrow mesenchymal stem cells (BMSCs) attenuate pancreatic injury via mediating oxidative stress in severe acute pancreatitis (SAP). The SAP model was established in rats. Phosphate buffered saline (PBS) or BMSCs were injected into the rats by tail veins. ML385 was used to down-regulate Nrf2 expression in rats. Pancreatic pathological score was used to evaluated pancreatic injury. Inflammatory-associated cytokines, serum lipase and amylase, levels of myeloperoxidase, malondialdehyde, reactive oxygen species and superoxide dismutase, as well as catalase activity were measured for injury severity evaluation. ML385 aggravates oxidative stress in SAP + ML385 group, compared with SAP + PBS group. BMSCs transplantation alleviated pancreatic injury and enhance antioxidant tolerance in SAP + BMSCs group, while ML385 administration weakened this efficacy in SAP + BMSCs + ML385 group. In addition, BMSCs promoted Nrf2 nuclear translocation via PI3K/AKT signaling pathway. Besides, BMSCs reduced inflammatory response by inhibiting NF-κB signaling pathway in SAP. BMSCs can inhibit oxidative stress and reduce pancreatic injury via inducing Nrf2 nuclear translocation in SAP.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Pancreatitis , Ratas , Animales , Pancreatitis/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Enfermedad Aguda , Médula Ósea/metabolismo , Médula Ósea/patología , Ratas Sprague-Dawley , Células Madre Mesenquimatosas/metabolismo , Estrés Oxidativo
4.
Chem Biodivers ; 19(7): e202200294, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35594039

RESUMEN

The two novel polysaccharides, DMP-1 and DMP-2, with molecular weights of 4.1553×105  kDa and 1.9764×105  kDa, respectively, were isolated from Dracocephalum moldavica. The structural characterization indicated that DMP-1 and DMP-2 shared a similar backbone consisting of →5)-Araf-(1→, Manp-(1→, Glcp-(1→, →2)-Manp-(1→, →6)-Glcp-(1→ and →3,6)-Galp-(1→ with a different molar ratios and triple-helix structures with α- and ß-type glycosidic bonds. The anti-complementary activity evaluation showed that DMP-1 and DMP-2 had strong complement inhibition through the classical pathway (CP), alternative pathway (AP) and lectin pathway (LP). Mechanistic studies indicated that DMP-1 can block the activation cascade of the complement system by targeting C2, C3, C5, C9, Factor B and Factor P, and that DMP-2 inhibited complement activation by blocking C2, C3, C4, C5, C9 and Factor B.


Asunto(s)
Factor B del Complemento , Lamiaceae , Activación de Complemento , Polisacáridos/química
5.
Chem Biodivers ; 19(8): e202200525, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35841390

RESUMEN

The polysaccharides from the rhizomes of Belamcanda chinensis (L.) DC. (BCPs) were obtained by optimal water extraction (extraction temperature 84 °C, liquid to solid ratio 42 mL/g and extraction time 100 min), the extraction yield of BCPs was 23.01±0.27 % (n=3). Furthermore, two novel polysaccharides (BCP-A1 and BCP-B1) were purified by column chromatography. The BCP-A1 (6.0820×104  kDa) was composed of ß-D-Manp-(1→, ß-D-Glcp-(1→, →4)-α-D-Galp-(1→ and →3,4)-ß-D-Galp-(1→, and BCP-B1 (2.2744×104  kDa) was composed of →5)-α-L-Araf-(1→, ß-D-Manp-(1→, ß-D-Glcp-(1→, →4)-α-D-Glcp, →4)-α-D-Galp-(1→, →4)-α-D-GalpA-(1→ and →3,4)-ß-D-Galp-(1→. In anticomplementary experiments, BCP-A1 (CH50 : 0.009±0.003 mg/mL; AP50 : 0.015±0.003 mg/mL) and BCP-B1 (CH50 : 0.004±0.001 mg/mL; AP50 : 0.028±0.005 mg/mL) exhibited potent anticomplementary activity, and acted on C2-, C4- and Factor B components. Our study provides a foundation for BCP-A1 and BCP-B1 as potential complement inhibitors to treat diseases involving with excessive activation of the complement system.


Asunto(s)
Polisacáridos , Rizoma , Proteínas del Sistema Complemento , Polisacáridos/química , Polisacáridos/farmacología , Rizoma/química
6.
J Asian Nat Prod Res ; 24(8): 746-753, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35137660

RESUMEN

Two new stilbene glucosides, trans-3,5-dihydroxy-4-methoxystilbene 3-O-ß-D-glucopyranoside (1), cis-3,5-dihydroxy-4-methoxystilbene 3-O-ß-D-glucopyranoside (2), one new benzoic acid derivative, cis-4-hydroxy-3-hydroxymethyl-2-butenyl benzoate 4-O-ß-D-glucopyranoside (3), and four known compounds (4 - 7) were isolated from Tournefortia sibirica L. The structures of these compounds were elucidated on the basis of spectral data. Anti-inflammatory effects of compounds (1 - 7) were evaluated in terms of inhibition on production of NO, TNF-α and IL-6 in LPS-induced RAW 264.7 cells. Compounds 1, 2 and 5 - 7 could inhibit the levels of NO, TNF-α and IL-6 in LPS-induced RAW264.7 cells with IC50 values ranging from 40.96 to 88.76 µM.


Asunto(s)
Boraginaceae , Estilbenos , Ácido Benzoico/farmacología , Glucósidos/química , Glucósidos/farmacología , Interleucina-6 , Lipopolisacáridos/farmacología , Estructura Molecular , Estilbenos/química , Estilbenos/farmacología , Factor de Necrosis Tumoral alfa
7.
BMC Genomics ; 22(1): 707, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34592920

RESUMEN

BACKGROUND: The order Oedogoniales within the single family Oedogoniaceae comprised of three genera, Oedogonium, Oedocladium, and Bulbochaete based on traditional morphological criteria. While several molecular phylogenetic studies have suggested that both Oedogonium and Oedocladium may not be monophyletic, broader taxon sampling and large amounts of molecular data acquisition could help to resolve the phylogeny and evolutionary problems of this order. This study determined five chloroplast (cp) genomes of Oedogonium species and aimed to provide further information on cp genome for a better understanding of the phylogenetic and evolutionary relationships of the order Oedogoniales. RESULTS: The five Oedogonium cp genomes showed typical quadripartite and circular structures, and were relatively conserved in their structure, gene synteny, and inverted repeats boundaries in general, except for small variation in genome sizes, AT contents, introns, and repeats. Phylogenetic analyses based on 54 cp protein-coding genes examined by maximum likelihood and Bayesian analyses using amino acid and nucleotide datasets indicated that both Oedocladium and Oedogonium are polyphyletic groups. A positively selected gene (psbA) was identified in the two Oedocladium species and the terrestrial Oedogonium species, indicating that terrestrial Oedogoniales taxa may have undergone adaptive evolution to adjust to the difference in light intensity between aquatic and terrestrial habitats. CONCLUSIONS: Our results enrich the data on cp genomes of the genus Oedogonium. The availability of these cp genomes can help in understanding the cp genome characteristics and resolve phylogenetic and evolutionary relationships of the order Oedogoniales.


Asunto(s)
Genoma del Cloroplasto , Teorema de Bayes , Evolución Molecular , Tamaño del Genoma , Filogenia , Secuenciación Completa del Genoma
8.
J Eukaryot Microbiol ; 68(5): e12858, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34022092

RESUMEN

Filamentous green algae Chaetophorales present numerous taxonomic problems as many other green algae. Phylogenetic analyses based on nuclear genes have limited solutions. Studies with appropriate chloroplast molecular markers may solve this problems; however, suitable molecular markers for the order Chaetophorales are still unknown. In this study, 50 chloroplast genomes of Chlorophyceae, including 15 of Chaetophorales, were subjected to single protein-coding gene phylogenetic analyses, and substitution rate and evolutionary rate assays, and PCR amplification verification was conducted to screen the suitable molecular markers. Phylogenetic analyses of three chloroplast representative genes (psaB, tufA, and rbcL) amplified from 124 strains of Chaetophorales showed that phylogenetic relationships were not improved by increasing the number of samples, implying that the genes themselves, rather than limited samples, were the reason for the unsupported Topology I. Seven genes (atpF, atpI, ccsA, cemA, chlB, psbB, and rpl2) with robust support were selected to be the most suitable molecular markers for phylogenetic analyses of Chaetophorales, and the concatenated seven genes could replace the time-consuming and labor-intensive phylogenetic analyses based on chloroplast genome to some extent. To further solve the taxonomic problems of Chaetophorales, suitable chloroplast markers combined with more taxon-rich approach could be helpful and efficient.


Asunto(s)
Chlorophyceae , Chlorophyta , Genoma del Cloroplasto , Secuencia de Bases , Chlorophyceae/genética , Chlorophyta/genética , ADN de Cloroplastos/genética , Evolución Molecular , Filogenia
9.
J Phycol ; 57(4): 1167-1186, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33713360

RESUMEN

The Trebouxiophyceae include Chlorellales, Prasiolales, Trebouxiales, Microthamniales, and numerous members for which taxonomic locations have not been determined. The Watanabea clade is a group in the Trebouxiophyceae of Chlorella-like taxa, which are predominantly solitary and terrestrial. With the increase in descriptions of new species within the Watanabea clade in recent years, it is necessary to define the boundary and taxonomic status of the clade. In this study, nineteen strains of terrestrial algae collected from China were investigated based on molecular and morphological data, involving phylogenetic analyses, light and electron microscopy, and ITS-2 secondary structures. These 19 strains were described as five known species and 12 novel ones. Based on the consistent topological structures of the phylogenetic analyses for three taxonomic levels (the core Chorophyta, Trebouxiophyceae based on 18S sequences, Watanabeales and Symbiochloris based on 18S, 5.8S, ITS2 and rbcL gene sequences) and common morphological characteristics, especially the key phenotypic feature of unequally sized autospores, the Watanabea clade was defined as a new order, Watanabeales ord. nov., with one family, Watanabeaceae fam. nov. The boundary of Watanabeales was delineated and included the genera Chloroidium, Calidiella, Jaagichlorella, Kalinella, Massjukichlorella, Mysteriochloris, Polulichloris, Phyllosiphon, Watanabea, and Viridiella. Symbiochloris did not belong to Watanabeales according to the phylogenetic analyses and the reproduction by equal-sized autospores, aplanospores, or zoospores. The Watanabeales were separated into four groups during the phylogenetic analyses, but no regular differences in habitats or morphology could be used as the morphological basis to split Watanabeales into the four groups.


Asunto(s)
Chlorella , China , Filogenia , Análisis de Secuencia de ADN
10.
J Phycol ; 57(4): 1151-1166, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33529378

RESUMEN

Commercial cultivation of eukaryotic microalgae has so far employed a unicellular form of species only (e.g., Chlorella pyrenoidosa, Dunaliella salina, and Haematococcus pluvialis). In this study, we assessed the feasibility of using the filamentous eukaryotic microalga Klebsormidium sp. LGX80 as a new cultivar for biomass and lipid production. The effects of different forms and concentrations of nitrogen on growth and lipid production of Klebsormidium sp. LGX80 were studied by using a glass column (ø4.5 × 60 cm) photobioreactor under laboratory conditions. Growth and lipid production of the new strain were further evaluated in an outdoor pilot-scale tubular photobioreactor. The results showed that when supplied with urea as a source of nitrogen Klebsormidium sp. LGX80 yielded a final biomass concentration of 8.49 ± 0.10 g · L-1 in which a cellular lipid content was 59.2 ± 0.4% DW. Under such conditions, the biomass and lipid productivities were 471.7 ± 5.9 and 248.1 ± 0.0 mg · L-1  · d-1 , respectively. Fatty acid analysis revealed that the main fatty acids of Klebsormidium sp. LGX80 were palmitic acid (C16:0), linoleic acid (C18:2ω6), and linolenic acid (C18:3ω3), of which linoleic acid (C18:2ω6) accounted for up to 67.5 ± 0.1% of total fatty acids. When grown outdoors in a 13,000-L tubular photobioreactor with an initial nitrogen concentration of 3 mM urea, Klebsormidium sp. LGX80 reached the highest biomass concentration of 2.63 ± 0.09 g · L-1 with the cells containing 38.0 ± 0.5% lipids (% DW), resulting in the volumetric biomass and lipid productivities of 147.2 ± 3.6 and 37.9 ± 0.9 mg · L-1  d-1 , respectively. The results of light:dark cycle experiment showed that a durative and prolonged light irradiation hindered the biosynthesis of chlorophyll a and chlorophyll b in the cells, but promoted the carotenoid accumulation. These results suggested that Klebsormidium sp. LGX80 can be a potential oleaginous filamentous microalga for commercial production of microalgal oils.


Asunto(s)
Chlorella , Microalgas , Streptophyta , Biomasa , Clorofila A , Ácidos Grasos , Lípidos
11.
BMC Genomics ; 21(1): 442, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32590931

RESUMEN

BACKGROUND: Order Chaetophorales currently includes six families, namely Schizomeridaceae, Aphanochaetaceae, Barrancaceae, Uronemataceae, Fritschiellaceae, and Chaetophoraceae. The phylogenetic relationships of Chaetophorales have been inferred primarily based on short and less informative rDNA sequences. This study aimed to phylogenetically reconstruct order Chaetophorales and determine the taxonomic scheme, and to further understand the evolution of order Chaetophorales. RESULTS: In the present study, seven complete and five fragmentary chloroplast genomes were harvested. Phylogenomic and comparative genomic analysis were performed to determine the taxonomic scheme within Chaetophorales. Consequently, Oedogoniales was found to be a sister to a clade linking Chaetophorales and Chaetopeltidales. Schizomeriaceae, and Aphanochaetaceae clustered into a well-resolved basal clade in Chaetophorales, inconsistent with the results of phylogenetic analysis based on rDNA sequences. Comparative genomic analyses revealed that the chloroplast genomes of Schizomeriaceae and Aphanochaetaceae were highly conserved and homologous, highlighting the closest relationship in this order. Germination types of zoospores precisely correlated with the phylogenetic relationships. CONCLUSIONS: chloroplast genome structure analyses, synteny analyses, and zoospore germination analyses were concurrent with phylogenetic analyses based on the chloroplast genome, and all of them robustly determined the unique taxonomic scheme of Chaetophorales and the relationships of Oedogoniales, Chaetophorales, and Chaetopeltidales.


Asunto(s)
Chlorophyceae/clasificación , Cloroplastos/genética , Análisis de Secuencia de ADN/métodos , Chlorophyceae/genética , Chlorophyceae/crecimiento & desarrollo , ADN Ribosómico/genética , Evolución Molecular , Genoma del Cloroplasto , Genómica , Germinación , Filogenia , Sintenía
12.
J Eukaryot Microbiol ; 67(3): 369-382, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31958181

RESUMEN

Members of the Watanabea clade of Trebouxiophyceae are genetically diverse and widely distributed in all kinds of habitats, especially in most terrestrial habitats. Ten new strains of terrestrial algae isolated from the tropical rainforest in China, and four published strains were investigated in this study. Morphological observation and molecular phylogenetic analyses based on the 18S, ITS, rbcL, and tufA genes were used to identify the new strains. Four previously described species were reinvestigated to supplement molecular data and autospores' morphological photographs. The phylogenetic analyses based on 18S only, the concatenated dataset of 18S and ITS, as well as the concatenated dataset of rbcL and tufA, showed the same phylogenetic positions and relationships of these new strains. According to the phylogenetic analysis and morphological comparisons results, we described these 10 strains as four new members within the Watanabea clade, Polulichloris yunnanensis sp. nov., Polulichloris ovale sp. nov., Massjukichlorella orientale sp. nov., and Massjukichlorella minus sp. nov., and two known species, Massjukichlorella epiphytica, and Mysteriochloris nanningensis. Additionally, we provide strong evidence proving that Phyllosiphon, Mysteriochloris, Polulichloris, and Desertella all reproduce through unequal sized autospores.


Asunto(s)
Chlorophyta/clasificación , Proteínas Fúngicas/genética , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN/métodos , Teorema de Bayes , China , Chlorophyta/genética , Chlorophyta/ultraestructura , ADN de Algas/genética , ADN Ribosómico/genética , Funciones de Verosimilitud , Fenotipo , Filogenia
13.
J Phycol ; 56(4): 895-907, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32180225

RESUMEN

Samples of Pithophoraceae, collected in diverse freshwater and damp terrestrial habitats from tropical and subtropical China, were characterized morphologically and ultrastructurally, and their phylogenetic position was determined based on nuclear ribosomal DNA sequences. Our phylogenetic analysis resolved a novel lineage of Pithophoraceae, sister to Aegagropilopsis. Based on our phylogenetic results, morphological observations and comparative rDNA ITS2 secondary structure analysis, we propose Chlorocladiella gen. nov., characterized by a well-developed system of prostrate filaments, and describe four new species, C. cochlea sp. nov., C. erecta sp. nov., C. medogensis sp. nov., and C. pisformis sp. nov. Two species were found growing on damp soil, which is an unusual habitat for cladophoralean green algae, indicating that the diversity of Cladophorales in terrestrial habitats may be greater than currently recognized.


Asunto(s)
Chlorophyta , China , Chlorophyta/genética , ADN Ribosómico , Ecosistema , Agua Dulce , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN
14.
J Phycol ; 55(1): 74-83, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30347440

RESUMEN

The broadly defined genus Chaetophora consisted of species with minute, uniseriate branching filaments enveloped in soft or firm mucilage forming macroscopic growths that are spherical, hemispherical, and tubercular or arbuscular, growing epiphytically on freshwater aquatic plants and other submerged surfaces in standing or fast-flowing water. Recent molecular analyses clearly showed that this genus was polyphyletic. In this study, eight strains of Chaetophora and three strains of Stigeoclonium were identified and successfully cultured. In combination with the morphological data, a concatenated data set of four markers (18S + 5.8S + ITS2+ partial 28S rDNA) was also used to determine their taxonomic relationships and phylogenetic positions. The molecular analysis resolved the broadly defined Chaetophora to at least two genera. Species with a globose thallus of genus Chaetophora formed a separate monophyletic clade, which clearly separated from, a type of lobe-form Chaetophora species. Therefore, we propose to erect a new genus, Chaetophoropsis, which includes all globose species of the Chaetophora. Chaetophoropsis aershanensis was determined to be a new species, based on its special characteristic of profuse long rhizoids. Stigeoclonium polyrhizum, as the closest relative to Chaetophoropsis, revealed its distant relationships to other species of Stigeoclonium. A globose thallus with a thick, soft mucilage matrix, and special rhizoidal branches lent further support to the placement of S. polyrhizum in the genus Chaetophoropsis and had the closest relationship to C. aershanensis. Taxonomic diversity was proven by distinctive morphological differences and by phylogenetic divergence in the broadly defined Chaetophora identified herein.


Asunto(s)
Chlorophyceae , Chlorophyta , ADN Ribosómico , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN
15.
J Phycol ; 55(6): 1290-1305, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31411734

RESUMEN

The genus Coelastrella was established by Chodat (Bull. Soc. Bot. Geneve, 13 [1922] 66), and was characterized as being unicellular or in few-celled aggregations with many longitudinal ribs on the cell wall. Many species of this genus showed strong ability to accumulate carotenoids and oils, so they have recently attracted much attention from researchers due to its potential applicability in the energy and food industries. In this study, a total of 23 strains of Coelastrella were sampled from China, and three new species and two new varieties were described: C. thermophila sp. nov., C. yingshanensis sp. nov., C. tenuitheca sp. nov., C. thermophila var. globulina var. nov., C. rubescens var. oocystiformis var. nov. Besides 18S rDNA and ITS2 sequences, we have newly sequenced the tufA gene marker for this taxon. Phylogenetic analysis combined with morphological studies revealed four morphotypes within the Coelastrella sensu lato clade, which contained the morphotype of original Coelastrella, original Scotiellopsis, Asterarcys, and morphotype of C. vacuolata and C. tenuitheca sp. nov. The relationships between morphological differences and phylogenic diversity based on different markers were discussed. Our results support that 18S rDNA was too conserved to be used a species-specific or even a genus-specific marker in this clade. The topology of tufA gene-based phylogenetic tree had a better match with the morphological findings.


Asunto(s)
Chlorophyta , China , Chlorophyceae , ADN Ribosómico , Filogenia , Análisis de Secuencia de ADN
16.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-30974837

RESUMEN

Trentepohliales is an aerial order of Chlorophyta with approximately 80 species distributed mainly in tropical and subtropical regions. The taxonomy of this genus is quite difficult and presents a challenge for many phycologists. Although plentiful molecular data is available, most of the sequences are not identified at the species level. In the present study, we described a new specimen with detailed morphological data and identified it as Trentepohlia odorata. A phylogenetic analysis showed T. odorata as a novel lineage in Trentepohliales. T. odorata has the closest relationship with T. annulata, which is expected since sporangia of both species are without stalk cell and with dorsal pore. Species with such morphological characteristics may represent deep lineages in Trentepohliales. Although an increasing number of chloroplast genomes of Ulvophyceae have been reported in recent years, the whole plastome of Trentepohliales has not yet been reported. Thus, the chloroplast genome of Trentepohlia odorata was reported in the present study. The whole plastome was 399,372 bp in length, with 63 predicted protein-coding genes, 31 tRNAs, and 3 rRNAs. Additionally, we annotated 95 free-standing open reading frames, of which seven were annotated with plastid origins, 16 with eukaryotic genome origins, and 33 with bacterial genome origins. Four rpo genes (rpoA, rpoB, rpoC1, and rpoC2) were annotated within ORF clusters. These four genes were fragmented into several (partial) ORFs by in-frame stop codons. Additionally, we detected a frame shift mutation in the rpoB gene. The phylogenetic analysis supported that Trentepohliales clustered with Dasycladales and nested into the BDT clade (Bryopsidales, Dasycladales and Trentepohliales). Our results present the first whole chloroplast genome of a species of Trentepohliales and provided new data for understanding the evolution of the chloroplast genome in Ulvophyceae.


Asunto(s)
Chlorophyta , ADN de Cloroplastos/genética , Evolución Molecular , Genoma del Cloroplasto , Filogenia , Chlorophyta/clasificación , Chlorophyta/genética , Orden Génico , Sistemas de Lectura Abierta
17.
BMC Plant Biol ; 18(1): 365, 2018 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-30563464

RESUMEN

BACKGROUD: Foliicolous algae are a common occurrence in tropical forests. They are referable to a few simple morphotypes (unicellular, sarcinoid-like or filamentous), which makes their morphology of limited usefulness for taxonomic studies and species diversity assessments. The relationship between algal community and their host phyllosphere was not clear. In order to obtain a more accurate assessment, we used single molecule real-time sequencing of the 18S rDNA gene to characterize the eukaryotic algal community in an area of South-western China. RESULT: We annotated 2922 OTUs belonging to five classes, Ulvophyceae, Trebouxiophyceae, Chlorophyceae, Dinophyceae and Eustigmatophyceae. Novel clades formed by large numbers sequences of green algae were detected in the order Trentepohliales (Ulvophyceae) and the Watanabea clade (Trebouxiophyceae), suggesting that these foliicolous communities may be substantially more diverse than so far appreciated and require further research. Species in Trentepohliales, Watanabea clade and Apatococcus clade were detected as the core members in the phyllosphere community studied. Communities from different host trees and sampling sites were not significantly different in terms of OTUs composition. However, the communities of Musa and Ravenala differed from other host plants significantly at the genus level, since they were dominated by Trebouxiophycean epiphytes. CONCLUSION: The cryptic diversity of eukaryotic algae especially Chlorophytes in tropical phyllosphere is very high. The community structure at species-level has no significant relationship either with host phyllosphere or locations. The core algal community in tropical phyllopshere is consisted of members from Trentepohliales, Watanabea clade and Apatococcus clade. Our study provided a large amount of novel 18S rDNA sequences that will be useful to unravel the cryptic diversity of phyllosphere eukaryotic algae and for comparisons with similar future studies on this type of communities.


Asunto(s)
Chlorophyta/genética , ADN Ribosómico , Árboles , China , Chlorophyceae/clasificación , Chlorophyceae/genética , Chlorophyta/clasificación , Ecosistema , Filogenia , Reacción en Cadena de la Polimerasa , Clima Tropical
18.
Eur Radiol ; 28(10): 4389-4396, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29713780

RESUMEN

OBJECTIVE: To objectively quantify intracranial hematoma (ICH) enlargement by analysing the image texture of head CT scans and to provide objective and quantitative imaging parameters for predicting early hematoma enlargement. METHODS: We retrospectively studied 108 ICH patients with baseline non-contrast computed tomography (NCCT) and 24-h follow-up CT available. Image data were assessed by a chief radiologist and a resident radiologist. Consistency analysis between observers was tested. The patients were divided into training set (75%) and validation set (25%) by stratified sampling. Patients in the training set were dichotomized according to 24-h hematoma expansion ≥ 33%. Using the Laplacian of Gaussian bandpass filter, we chose different anatomical spatial domains ranging from fine texture to coarse texture to obtain a series of derived parameters (mean grayscale intensity, variance, uniformity) in order to quantify and evaluate all data. The parameters were externally validated on validation set. RESULTS: Significant differences were found between the two groups of patients within variance at V1.0 and in uniformity at U1.0, U1.8 and U2.5. The intraclass correlation coefficients for the texture parameters were between 0.67 and 0.99. The area under the ROC curve between the two groups of ICH cases was between 0.77 and 0.92. The accuracy of validation set by CTTA was 0.59-0.85. CONCLUSION: NCCT texture analysis can objectively quantify the heterogeneity of ICH and independently predict early hematoma enlargement. KEY POINTS: • Heterogeneity is helpful in predicting ICH enlargement. • CTTA could play an important role in predicting early ICH enlargement. • After filtering, fine texture had the best diagnostic performance. • The histogram-based uniformity parameters can independently predict ICH enlargement. • CTTA is more objective, more comprehensive, more independently operable, than previous methods.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Hematoma/diagnóstico por imagen , Hemorragias Intracraneales/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador , Adulto , Anciano , Progresión de la Enfermedad , Diagnóstico Precoz , Femenino , Hematoma/patología , Humanos , Hemorragias Intracraneales/patología , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos
19.
J Eukaryot Microbiol ; 65(3): 382-391, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29080384

RESUMEN

The Parachlorella clade was put forward as a group within the family Chlorellaceae in 2004. Recent molecular analyses have revealed that Dictyosphaerium morphotype algae form several independent lineages within the Parachlorella clade, and new genera and species have been established. In this study, we focus on the diversity of Dictyosphaerium morphotype algae within the Parachlorella clade, based on 42 strains from China. We used combined analyses of morphology and molecular data based on SSU and internal transcribed spacer region (ITS) rDNA sequences to characterize these algae. In addition, the secondary structure of ITS2 was compared to delineate new lineages. Our results revealed high phylogenic diversity of Dictyosphaerium morphotype algae, and we describe five distinct lineages. We examined the morphological features of these five lineages, and morphological differences are difficult to find compared with other Dictyosphaerium morphotype algae. The five distinct lineages were not described as new genera currently. We lastly discuss the taxonomic problems regarding the Dictyosphaerium morphotype within the Parachlorella clade, and possible solutions are considered.


Asunto(s)
Chlorophyta/clasificación , Chlorophyta/genética , ADN de Algas/genética , ADN Intergénico/genética , China , Cloroplastos/fisiología , Filogenia
20.
J Eukaryot Microbiol ; 65(2): 200-210, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28792654

RESUMEN

The Oocystaceae family is generally considered to contain common freshwater eukaryotic microalgae, and few are reported living in semi-saline habitats. Our latest ecological survey in Qinghai Lake and Angzicuo Lake, both large, closed, high-altitude, semi-saline lakes located on the Qinghai-Tibet plateau in China, revealed Oocystaceae species as a dominant group among plankton. Since limited knowledge exists about semi-saline species in the Oocystaceae family, a taxonomical study was carried out using morphological and phylogenetic methods. Using this approach, four new strains of Oocystaceae were identified and successfully cultured in the lab. Molecular results correlated with morphological characters and resolved these species into at least three genera. A new genus, Euchlorocystis, with type species Euchlorocystis subsalina, is described here as having the distinctive morphology of multiple pyrenoids per chloroplast among Oocystaceae, and an independent phylogenetic position at the base of the Oocystaceae. Similarly, the genus Densicystis, with type species Densicystis glomerata, is newly proposed here as having a unique colony morphology of dozens or hundreds of little cells tightly embedded in ellipsoid to round mucilage masses. Oocystis marina, originally described from the Baltic Sea, was also identified in Qinghai Lake and Angzicuo Lake and phylogenetically positioned in the semi-saline clade of the Oocystaceae. The result that a marine species was detected in the closed inland lakes implies a further need to reevaluate the origins of these species.


Asunto(s)
Chlorophyta/clasificación , Chlorophyta/genética , Chlorophyta/ultraestructura , Filogenia , Altitud , China , Ecosistema , Lagos , Microscopía Electrónica de Transmisión , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
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