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1.
Environ Sci Technol ; 58(27): 11988-11997, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38875444

RESUMO

Thousands of mass peaks emerge during molecular characterization of natural dissolved organic matter (DOM) using ultrahigh-resolution mass spectrometry. While mass peaks assigned to certain molecular formulas have been extensively studied, the uncharacterized mass peaks that represent a significant fraction of organic matter and convey biogenic elements and energy have been previously ignored. In this study, we introduce the term dark DOM (DDOM) for unassigned mass peaks and have explored its characteristics and environmental behaviors using a data set of 38 DOM extracts covering the Yangtze River-to-ocean continuum. We identified a total of 9141 DDOM molecules, which exhibited higher molecular weight and greater diversity than the DOM subset with assigned DOM formulas. Although DDOM contributed a smaller fraction of relative abundance, it significantly impacted the molecular weight and molecular composition of bulk DOM. A portion of DDOM with higher molecular weight was found to increase molecular abundance across the river-to-ocean continuum. These compounds could contain halogenated organic molecules and might have a high potential to contribute to the refractory organic carbon pool. With this study, we underline the contribution of dark matter to the total DOM pool and emphasize that more DDOM research is needed to understand its contribution to global biogeochemical cycles and carbon sequestration.


Assuntos
Rios , Rios/química , Oceanos e Mares , Monitoramento Ambiental , Espectrometria de Massas , Compostos Orgânicos/análise
2.
Environ Res ; 252(Pt 3): 119040, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692424

RESUMO

Floods in global large rivers modulate the transport of dissolved organic carbon (DOC) and estuarine hydrological characteristics significantly. This study investigated the impact of a severe flood on the sources and age of DOC in the Yangtze River Estuary (YRE) in 2020. Comparing the flood period in 2020 to the non-flood period in 2017, we found that the flood enhanced the transport of young DOC to the East China Sea (ECS), resulting in significantly enriched Δ14C-DOC values. During the flood period, the proportion of modern terrestrial organic carbon (OC) was significantly higher compared to the non-flood period. Conversely, the proportion of pre-aged sediment OC was significantly lower during the flood period. The high turbidity associated with the flood facilitated rapid transformation and mineralization of sedimentary and fresh terrestrial OC, modifying the sources of DOC. The flux of modern terrestrial OC transported to the ECS during the flood period was 1.58 times higher than that of the non-flood period. These findings suggest that floods can modulate the sources and decrease the age of DOC, potentially leading to increased greenhouse gas emissions. Further research is needed to understand the long-term impacts of floods on DOC dynamics in global estuaries.


Assuntos
Carbono , Estuários , Inundações , Rios , China , Rios/química , Carbono/análise , Monitoramento Ambiental , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise
3.
Environ Res ; 257: 119251, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38815714

RESUMO

The bioavailable diverse dissolved organic matter (DOM) present in glacial meltwater significantly contributes to downstream carbon cycling in mountainous regions. However, the comprehension of molecular-level characteristics of riverine DOM, from tributary to downstream and their fate in glacier-fed desert rivers remains limited. Herein, we employed spectroscopic and high-resolution mass spectrometry techniques to study both optical and molecular-level characteristics of DOM in the Tarim River catchment, northwest China. The results revealed that the DOC values in the downstream were higher than those in the tributaries, yet they remained comparable to those found in other glacier-fed streams worldwide. Five distinct components were identified using EEM-PARAFAC analysis in both tributary and downstream samples. The dominance of three protein-like components in tributary samples, contrasting with a higher presence of humic-like components in downstream samples, which implied that the dilution and alterations of the glacier DOM signature and overprinting with terrestrial-derived DOM. Molecular composition revealed that thousands of compounds with higher molecular weight and increased aromaticity were transformed, generated and introduced from terrestrial inputs during downstream transportation. The twofold rise in polycyclic aromatic and polyphenolic compounds observed downstream compared to tributaries indicated a greater influx of terrestrial organic matter introduced into the downstream during water transportation. The study suggests that the glacier-sourced DOM experienced minimal photodegradations, with limited influence from human activities, while also being shaped by terrestrial inputs during its transit in the alpine-arid region. This unique scenario offers valuable insights into comprehending the fate of DOM originating from glacial meltwater in arid mountainous regions.


Assuntos
Camada de Gelo , Rios , China , Rios/química , Camada de Gelo/química , Monitoramento Ambiental/métodos , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Substâncias Húmicas/análise , Espectrometria de Massas , Clima Desértico
4.
Ecotoxicol Environ Saf ; 281: 116576, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878562

RESUMO

The accumulation of rare earth elements (REEs) in the global environment poses a threat to plant health and ecosystem stability. Stomata located on leaves serve as the primary site for plant responses to REE-related threats. This study focused on lanthanum [La(III)], a prevalent REE in the atmospheric environment. Using interdisciplinary techniques, it was found that La(III) (≤80 µM) interfered with the fundamental rhythms of stomatal opening, related gene expression, and evapotranspiration in plants. Specifically, when exposed to low concentrations of La(III) (15 and 30 µM), the expression levels of six genes were increased, stomatal opening was enhanced, and the evapotranspiration rate was accelerated. The interference on stomatal rhythms was enhanced with higher concentrations of La(III) (60 and 80 µM), increasing the expression levels of six genes, stomatal opening, and evapotranspiration rate. To counter the interference of low concentrations of La(III) (15 and 30 µM), plants accelerated nutrient replenishment through La(III)-induced endocytosis, which the redundant nutrients enhanced photosynthesis. However, replenished nutrients failed to counter the disruption of plant biological rhythms at higher concentrations of La(III) (60 and 80 µM), thus inhibiting photosynthesis due to nutrient deficit. The interference of La(III) on these biological rhythms negatively affected plant health and ecosystem stability.


Assuntos
Arabidopsis , Regulação da Expressão Gênica de Plantas , Lantânio , Estômatos de Plantas , Transpiração Vegetal , Lantânio/toxicidade , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Transpiração Vegetal/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos
5.
Environ Sci Technol ; 57(46): 17900-17909, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37079797

RESUMO

Dissolved organic matter (DOM) is a complex mixture of molecules that constitutes one of the largest reservoirs of organic matter on Earth. While stable carbon isotope values (δ13C) provide valuable insights into DOM transformations from land to ocean, it remains unclear how individual molecules respond to changes in DOM properties such as δ13C. To address this, we employed Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterize the molecular composition of DOM in 510 samples from the China Coastal Environments, with 320 samples having δ13C measurements. Utilizing a machine learning model based on 5199 molecular formulas, we predicted δ13C values with a mean absolute error (MAE) of 0.30‰ on the training data set, surpassing traditional linear regression methods (MAE 0.85‰). Our findings suggest that degradation processes, microbial activities, and primary production regulate DOM from rivers to the ocean continuum. Additionally, the machine learning model accurately predicted δ13C values in samples without known δ13C values and in other published data sets, reflecting the δ13C trend along the land to ocean continuum. This study demonstrates the potential of machine learning to capture the complex relationships between DOM composition and bulk parameters, particularly with larger learning data sets and increasing molecular research in the future.


Assuntos
Carbono , Matéria Orgânica Dissolvida , Isótopos de Carbono , Espectrometria de Massas/métodos , Rios/química
6.
Environ Sci Technol ; 57(46): 17889-17899, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37248194

RESUMO

Dissolved organic matter (DOM) sustains a substantial part of the organic matter transported seaward, where photochemical reactions significantly affect its transformation and fate. The irradiation experiments can provide valuable information on the photochemical reactivity (photolabile, photoresistant, and photoproduct) of molecules. However, the inconsistency of the fate of irradiated molecules among different experiments curtailed our understanding of the roles the photochemical reactions have played, which cannot be properly addressed by traditional approaches. Here, we conducted irradiation experiments for samples from two large estuaries in China. Molecules that occurred in irradiation experiments were characterized by the Fourier transform ion cyclotron resonance mass spectrometry and assigned probabilistic labels to define their photochemical reactivity. These molecules with probabilistic labels were used to construct a learning database for establishing a suitable machine learning (ML) model. We further applied our well-trained ML model to "un-matched" (i.e., not detected in our irradiation experiments) molecules from five estuaries worldwide, to predict their photochemical reactivity. Results showed that numerous molecules with strong photolability can be captured solely by the ML model. Moreover, comparing DOM photochemical reactivity in five estuaries revealed that the riverine DOM chemistry largely determines their subsequent photochemical transformation. We offer an expandable and renewable approach based on ML to compatibly integrate existing irradiation experiments and shed insight into DOM transformation and degradation processes.


Assuntos
Matéria Orgânica Dissolvida , Compostos Orgânicos , Compostos Orgânicos/análise , Fotoquímica , Espectrometria de Massas , Estuários
7.
Environ Sci Technol ; 57(25): 9214-9223, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37303158

RESUMO

The impacts of human activities on the riverine carbon (C) cycle have only recently been recognized, and even fewer studies have been reported on anthropogenic impacts on C cycling in rivers draining the vulnerable alpine areas. Here, we examined carbon isotopes (δ13CDOC and Δ14CDOC), fluorescence, and molecular compositions of riverine dissolved organic matters (DOM) in the Bailong River catchment, the eastern edge of the Tibetan Plateau to identify anthropogenic impacts on the C cycle. Human activities show limited impact on dissolved organic carbon (DOC) concentration, but significantly increased the age of DOC (from modern to ∼1600 yr B.P.) and changed the molecular compositions through agriculture and urbanization despite in the catchment with low population density. Agricultural activities indirectly increased the leaching of N-containing aged organic matter from deep soil to rivers. Urbanization released S-containing aged C from fossil products into rivers directly through wastewater. The aged DOC from agricultural activity and wastewater discharge was partly biolabile and/or photolabile. This study highlights that riverine C is sensitive to anthropogenic disturbance. Additionally, the study also emphasizes that human activities reintroduce aged DOC into the modern C cycle, which would accelerate the geological C cycle.


Assuntos
Efeitos Antropogênicos , Rios , Humanos , Idoso , Tibet , Matéria Orgânica Dissolvida , Águas Residuárias , Carbono
8.
J Environ Manage ; 344: 118559, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37418915

RESUMO

Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) has been widely applied to characterize the molecular composition of dissolved organic matter (DOM) in different ecosystems. Most previous studies have explored the molecular composition of DOM focused on one or a few ecosystems, which prevents us from tracing the molecular composition of DOM from different sources and further exploring its biogeochemical cycling across ecosystems. In this study, a total of 67 DOM samples, including soil, lake, river, ocean, and groundwater, were analyzed by negative-ion electrospray ionization FT-ICR MS. Results show that molecular composition of DOM varies dramatically among diverse ecosystems. Specifically, the forest soil DOM exhibited the strongest terrestrial signature of molecules, while the seawater DOM showed the most abundant of biologically recalcitrant components, for example, the carboxyl-rich alicyclic molecules were abundant in the deep-sea waters. Terrigenous organic matter is gradually degraded during its transport along the river-estuary-ocean continuum. The saline lake DOM showed similar DOM characteristics with marine DOM, and sequestrated abundant recalcitrant DOM. By comparing these DOM extracts, we found that human activities likely lead to an increase in the content of S and N-containing heteroatoms in DOM, this phenomenon was commonly found in the paddy soil, polluted river, eutrophic lake, and acid mine drainage DOM samples. Overall, this study compared molecular composition of DOM extracted from various ecosystems, providing a preliminary comparison on the DOM fingerprint and an angle of view into biogeochemical cycling across different ecosystems. We thus advocate for the development of a comprehensive molecular fingerprint database of DOM using FT-ICR MS across a wider range of ecosystems. This will enable us to better understand the generalizability of the distinct features among ecosystems.


Assuntos
Matéria Orgânica Dissolvida , Água Subterrânea , Humanos , Ecossistema , Solo/química , Espectrometria de Massas
9.
J Environ Manage ; 334: 117259, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36764191

RESUMO

The hormetic effect of rare earth elements (REEs) has been found in a variety of crops and has been promoting crop growth for decades. Spraying leaves with REEs can enhance the endocytosis of plant roots. The non-selectivity of endocytosis is conducive to the direct absorption of environmental pollutants. The hyperaccumulator Solanum nigrum L. (S. nigrum), as a plant with high biomass and heavy metal tolerance, is a good candidate for phytoremediation. La(III), as a typical light REE, also has an obvious hormetic effect on S. nigrum. At 10 µM La(III), the biomass of S. nigrum reached the maximum, which was 89% greater than the control, and La(III) concentration was much lower than the previously reported optimum of 56 µM for general plants. In the present study, enhanced endocytosis after foliar spraying of La(III) was firstly observed in the root cell of hyperaccumulation plants, and La(III) increased the biomass of S. nigrum by improving the photosynthetic system, and promoting nutrient uptake and root development. The antioxidant defense system improved by La(III) contributed to the tolerance of S. nigrum to heavy metals. Applying a reasonable range of La(III) is beneficial to improving S. nigrum growth and tolerance of heavy metals. Compared with spraying deionized water, the translocation factor and bioaccumulation factor value of S. nigrum to cadmium increased by 15% and 21% respectively when spraying 10 µM La(III). Our findings provide a reference for improving hyperaccumulator plant growth and biomass, which improves phytoremediation efficiency.


Assuntos
Metais Pesados , Poluentes do Solo , Solanum nigrum , Lantânio , Biodegradação Ambiental , Poluentes do Solo/análise , Cádmio/farmacologia , Raízes de Plantas/química , Solo
10.
Gynecol Oncol ; 166(3): 567-575, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914979

RESUMO

OBJECTIVE: Understanding real-world treatment patterns and proportions of eligible patients in each line of treatment is imperative to inform future clinical trial designs and multi-line treatment algorithm development. METHODS: We conducted a retrospective observational cohort study of adult women who received first-line (1 L) therapy for r/mCC between 01 September 2014 and 31 December 2019, using The US Oncology Network electronic health records and chart review data. Patients were followed to 31 December 2020. Patient demographic and clinical characteristics, treatment patterns, and clinical outcomes were assessed descriptively. RESULTS: A total of 262 patients with r/mCC met study inclusion criteria (mean age = 53 years). The majority of patients in 1 L received platinum-based chemotherapy doublet plus bevacizumab (66%) or chemotherapy doublet alone (24%). Nearly half the patients (48%) completing 1 L received 2 L therapy. Among these patients, there was no consistent 2 L treatment of choice. Overall median time to treatment discontinuation was 3.5 months from 1 L treatment initiation, and median overall treatment-free interval was 2.1 months from 1 L discontinuation. Besides elevated serum creatinine, abnormal BMI indicated a directional trend for lower likelihood of receiving 2 L. Other predictors may include no prior bevacizumab, worse ECOG, and earlier disease prevention. CONCLUSIONS: >50% of the patients who initiated 1 L treatment did not receive 2 L therapy, highlighting the need for novel and effective treatment options. As the treatment landscape continues to evolve, we anticipate that more patients will live longer with more treatment options across multiple lines of therapies in the r/mCC setting.


Assuntos
Neoplasias do Colo do Útero , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/etiologia
11.
Environ Sci Technol ; 56(18): 12873-12885, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36083258

RESUMO

The light-absorbing organic aerosol (OA) constitutes an important fraction of absorbing components, counteracting major cooling effect of aerosols to climate. The mechanisms in linking the complex and changeable chemistry of OA with its absorbing properties remain to be elucidated. Here, by using solvent extraction, ambient OA from an urban environment was fractionated according to polarity, which was further nebulized and online characterized with compositions and absorbing properties. Water extracted high-polar compounds with a significantly higher oxygen to carbon ratio (O/C) than methanol extracts. A transition O/C of about 0.6 was found, below and above which the enhancement and reduction of OA absorptivity were observed with increasing O/C, occurring on the less polar and high polar compounds, respectively. In particular, the co-increase of nitrogen and oxygen elements suggests the important role of nitrogen-containing functional groups in enhancing the absorptivity of the less polar compounds (e.g., forming nitrogen-containing aromatics), while further oxidation (O/C > 0.6) on high-polar compounds likely led to fragmentation and bleaching chromophores. The results here may reconcile the previous observations about darkening or whitening chromophores of brown carbon, and the parametrization of O/C has the potential to link the changing chemistry of OA with its polarity and absorbing properties.


Assuntos
Poluentes Atmosféricos , Metanol , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Nitrogênio , Oxigênio , Material Particulado/análise , Solventes , Água/química
12.
Bioorg Med Chem Lett ; 28(4): 700-706, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29395973

RESUMO

We used the concept of bioisosteres to design and synthesize a novel series of dasatinib derivatives for the treatment of leukemia. Unfortunately, most of the dasatinib derivatives did not show appreciable inhibition against leukemia cell lines K562 and HL60. However, acrylamide compound 2c had comparable inhibitory activity with dasatinib against K562 cells (IC50 = 0.039 nM vs. 0.069 nM). And amide compound 2a and acrylamide compound 2c also had comparable inhibitory activity with dasatinib against the leukemia cell line HL60 (IC50 = 0.25 nM and 0.26 nM vs. 0.11 nM). Against the leukemia progenitor cell line KG1a, triazole compounds 15a and 15d-15f and oxadiazole compounds 24a-24d were more potent than dasatinib. In particular, the hydroxyl compounds 15a and 24a were about 64 and 180 fold more potent than dasatinib against KG1a cells (IC50 = 0.14 µM and 0.05 µM vs. 8.98 µM). Compounds 15a and 24a also inhibited colony formation in MCF-7 cells and inhibited cell migration in the cell wound scratch assay in B16BL6 cells. Moreover, hydroxyl compounds 15a and 24a had low toxicity in vivo.


Assuntos
Antineoplásicos/farmacologia , Dasatinibe/análogos & derivados , Dasatinibe/farmacologia , Leucemia/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Dasatinibe/síntese química , Dasatinibe/toxicidade , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Oxidiazóis/síntese química , Oxidiazóis/farmacologia , Oxidiazóis/toxicidade , Triazóis/síntese química , Triazóis/farmacologia , Triazóis/toxicidade
13.
Mol Biol Evol ; 33(1): 122-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26412445

RESUMO

The most gene-rich and bacterial-like mitochondrial genomes known are those of Jakobida (Excavata). Of these, the most extreme example to date is the Andalucia godoyi mitochondrial DNA (mtDNA), including a cox15 gene encoding the respiratory enzyme heme A synthase (HAS), which is nuclear-encoded in nearly all other mitochondriate eukaryotes. Thus cox15 in eukaryotes appears to be a classic example of mitochondrion-to-nucleus (endosymbiotic) gene transfer, with A. godoyi uniquely retaining the ancestral state. However, our analyses reveal two highly distinct HAS types (encoded by cox15-1 and cox15-2 genes) and identify A. godoyi mitochondrial cox15-encoded HAS as type-1 and all other eukaryotic cox15-encoded HAS as type-2. Molecular phylogeny places the two HAS types in widely separated clades with eukaryotic type-2 HAS clustering with the bulk of α-proteobacteria (>670 sequences), whereas A. godoyi type-1 HAS clusters with an eclectic set of bacteria and archaea including two α-proteobacteria missing from the type-2 clade. This wide phylogenetic separation of the two HAS types is reinforced by unique features of their predicted protein structures. Meanwhile, RNA-sequencing and genomic analyses fail to detect either cox15 type in the nuclear genome of any jakobid including A. godoyi. This suggests that not only is cox15-1 a relatively recent acquisition unique to the Andalucia lineage but also the jakobid last common ancestor probably lacked both cox15 types. These results indicate that uptake of foreign genes by mtDNA is more taxonomically widespread than previously thought. They also caution against the assumption that all α-proteobacterial-like features of eukaryotes are ancient remnants of endosymbiosis.


Assuntos
Alphaproteobacteria/genética , DNA Mitocondrial/genética , Transferência Genética Horizontal/genética , Simbiose/genética , Sequência de Aminoácidos , Eucariotos/genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
14.
Korean J Parasitol ; 55(2): 121-128, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28506033

RESUMO

Protozoan viruses may influence the function and pathogenicity of the protozoa. Trichomonas vaginalis is a parasitic protozoan that could contain a double stranded RNA (dsRNA) virus, T. vaginalis virus (TVV). However, there are few reports on the properties of the virus. To further determine variations in protein expression of T. vaginalis, we detected 2 strains of T. vaginalis; the virus-infected (V+) and uninfected (V-) isolates to examine differentially expressed proteins upon TVV infection. Using a stable isotope N-terminal labeling strategy (iTRAQ) on soluble fractions to analyze proteomes, we identified 293 proteins, of which 50 were altered in V+ compared with V- isolates. The results showed that the expression of 29 proteins was increased, and 21 proteins decreased in V+ isolates. These differentially expressed proteins can be classified into 4 categories: ribosomal proteins, metabolic enzymes, heat shock proteins, and putative uncharacterized proteins. Quantitative PCR was used to detect 4 metabolic processes proteins: glycogen phosphorylase, malate dehydrogenase, triosephosphate isomerase, and glucose-6-phosphate isomerase, which were differentially expressed in V+ and V- isolates. Our findings suggest that mRNA levels of these genes were consistent with protein expression levels. This study was the first which analyzed protein expression variations upon TVV infection. These observations will provide a basis for future studies concerning the possible roles of these proteins in host-parasite interactions.


Assuntos
Expressão Gênica , Proteínas de Protozoários/genética , Vírus de RNA , Trichomonas vaginalis/genética , Trichomonas vaginalis/virologia , Feminino , Glucose-6-Fosfato Isomerase/análise , Glucose-6-Fosfato Isomerase/isolamento & purificação , Glicogênio Fosforilase/análise , Glicogênio Fosforilase/isolamento & purificação , Glicólise/genética , Humanos , Malato Desidrogenase/análise , Malato Desidrogenase/isolamento & purificação , Masculino , Reação em Cadeia da Polimerase , Proteínas de Protozoários/análise , Proteínas de Protozoários/classificação , Proteínas de Protozoários/isolamento & purificação , RNA de Cadeia Dupla , RNA Mensageiro/análise , Tricomoníase/parasitologia , Trichomonas vaginalis/crescimento & desenvolvimento , Trichomonas vaginalis/metabolismo , Triose-Fosfato Isomerase/análise , Triose-Fosfato Isomerase/isolamento & purificação
15.
Mol Phylogenet Evol ; 101: 1-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27132173

RESUMO

Rhizaria is a major eukaryotic group of tremendous diversity, including amoebae with spectacular skeletons or tests (Radiolaria and Foraminifera), plasmodial parasites (Plasmodiophorida) and secondary endosymbionts (Chlorarachniophyta). Current phylogeny places Rhizaria in an unresolved trichotomy with Stramenopila and Alveolata (supergroup "SAR"). We assembled a 147-protein data set with extensive rhizarian coverage (M147), including the first transcriptomic data for a euglyphid amoeba. Phylogenetic pre-screening of individual proteins indicated potential problems with radically misplaced sequences due either to contamination of rhizarian sequences amplified from wild collected material and/or extremely long branches (xLBs). Therefore, two data subsets were extracted containing either all proteins consistently recovering rhizarian monophyly (M34) or excluding all proteins with ⩾3 xLBs (defined as ⩾2× the average terminal branch length for the tree). Phylogenetic analyses of M147 give conflicting results depending on the outgroup and method of analysis but strongly support an exclusive Rhizaria+Alveolata (R+A) clade with both data subsets (M34 and M37) regardless of phylogenetic method used. Support for an R+A clade is most consistent when a close outgroup is used and decreases with more distant outgroups, suggesting that support for alternative SAR topologies may reflect a long-branch attraction artifact. A survey of xLB distribution among taxa and protein functional category indicates that small "informational" proteins in particular have highly variable evolutionary rates with no consistent pattern among taxa.


Assuntos
Alveolados/classificação , Alveolados/metabolismo , Bases de Dados de Proteínas , Filogenia , Rhizaria/classificação , Rhizaria/metabolismo , Alveolados/genética , Genômica , Rhizaria/genética , Seleção Genética
16.
Eur Spine J ; 24 Suppl 4: S619-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25805579

RESUMO

INTRODUCTION: Nontraumatic posterior atlantooccipital dislocation has only been rarely reported. In the current study, the authors reported an extremely rare case of nontraumatic posterior atlantooccipital dislocation associated with atlantoaxial instability. MATERIALS AND METHODS: A 47-year-old female was referred with a history of neck pain for 5 years. The patient had no history of trauma. The axial rotation of range of motion of the cervical spine was severely restricted. Posterior atlantooccipital dislocation with atlantoaxial instability was confirmed through conventional radiography, computed tomography and magnetic resonance imaging. We performed realignment of the dislocation and posterior occipitocervical (C0-C2) fusion. After the surgery, the patient's symptoms improved significantly and she manifested neurological improvement. CONCLUSION: To our knowledge, this lesion has not been reported previously. Anomalies of upper cervical spine may have induced this instability.


Assuntos
Articulação Atlantoaxial/cirurgia , Articulação Atlantoccipital/cirurgia , Luxações Articulares/etiologia , Instabilidade Articular/complicações , Vértebras Cervicais/cirurgia , Feminino , Humanos , Luxações Articulares/diagnóstico , Luxações Articulares/cirurgia , Instabilidade Articular/diagnóstico , Instabilidade Articular/cirurgia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Fusão Vertebral/métodos , Tomografia Computadorizada por Raios X
17.
J Am Chem Soc ; 136(42): 14682-5, 2014 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-25291430

RESUMO

We report enhanced force detection selectivity based on Coulombic interactions through AFM tip modification for probing fine structures of the electric double layer (EDL) in ionic liquids. When AFM tips anchored with alkylthiol molecular layers having end groups with different charge states (e.g., -CH3, -COO(-), and -NH3(+)) are employed, Coulombic interactions between the tip and a specified layering structure are intensified or diminished depending on the polarities of the tip and the layering species. Systematic potential-dependent measurements of force curves with careful inspection of layered features and thickness analysis allows the fine structure of the EDL at the Au(111)-OMIPF6 interface to be resolved at the subionic level. The enhanced force detection selectivity provides a basis for thoroughly understanding the EDL in ionic liquids.

18.
BMC Pediatr ; 14: 256, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25286833

RESUMO

BACKGROUND: Mandibuloacral dysplasia type A (MADA) is a rare autosomal recessive disorder, characterized by growth retardation, skeletal abnormality with progressive osteolysis of the distal phalanges and clavicles, craniofacial anomalies with mandibular hypoplasia, lipodystrophy and mottled cutaneous pigmentation. Some patients may show progeroid features. MADA with partial lipodystrophy, more marked acral, can be caused by homozygous or compound heterozygous mutation in the gene encoding lamin A and lamin C (LMNA). MADA and Hutchinson-Gilford progeria syndrome are caused by the same gene and may represent a single disorder with varying degrees of severity. MAD patients characterized by generalized lipodystrophy (type B) affecting the face as well as extremities and severe progressive glomerulopathy present heterozygous compound mutations in the ZMPSTE24 gene. CASES PRESENTATIONS: We described a rare pedigree from Southern China, among them all three children presented with phenotypes of MADA associated progeria. The two elder sisters had developed severe mandibular hypoplasia associated progeria since the age of 1 year. The eldest sister showed a progressive osteolysis. The youngest son of 10 months showed severer lesions than those of his sisters at the same age, and presented possible muscle damage, and his symptoms progressed gradually. Three genes mutations including LMNA, ZMPSTE24 and BANF1 were tested in the family. LMNA gene sequencing revealed a homozygous missense mutation, c.1579C > T, p.R527C for all three siblings, and heterozygous mutations for their parents, whereas no mutations of ZMPSTE24 and BANF1 genes was detected among them. CONCLUSIONS: The same homozygous mutation of c.1579C > T of LMNA gene led to MADA associated progeria for the present family. The course of osteolysis for MADA is progressive.


Assuntos
Acro-Osteólise/genética , Homozigoto , Lamina Tipo A/genética , Lipodistrofia/genética , Mandíbula/anormalidades , Mutação , Progéria/genética , Povo Asiático/genética , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Masculino , Osteólise/genética , Linhagem , Doenças Raras/genética , Irmãos
19.
J Headache Pain ; 15: 18, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24670221

RESUMO

Erythermalgia is a rare cutaneous disorder characterized by attacking of erythema, pain and increased temperature, which primarily involves the extremities and may infrequently extend to the neck, face, ears and even the scrotum. We reported an 18-year-old woman who presented with 3 years history of sole involvement of attacking erythema, pain and warmth over her face and ears without any other associations. The frequency and severity of the flares progressed gradually during the course. Cutaneous examination revealed erythema, increased temperature and tenderness on the face and ears during the flare. The symptoms could be relieved rapidly by cooling. Dermatoscope showed that vessels inside the erythema were more dilated during the episode than after application of ice. The lesion is considered a rare variant of erythermalgia with sole involvement of face and ears. The symptoms had mild response to oral antihistamines, topical steroids and tacrolimus, but had excellent response to the combinative therapy of aspirin and paroxetins.


Assuntos
Orelha/patologia , Eritema/diagnóstico , Eritromelalgia/diagnóstico , Face/patologia , Dor/diagnóstico , Adolescente , Temperatura Corporal , Eritema/classificação , Eritema/complicações , Eritromelalgia/classificação , Eritromelalgia/complicações , Feminino , Humanos , Dor/classificação , Dor/complicações , Síndrome
20.
Sci Total Environ ; 912: 168915, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38030000

RESUMO

Rare earth elements (REEs) are important to enhance agricultural productivity. The utilization of phytoremediation as a green technology for addressing heavy metal (HMs) contamination in soil and wastewater has gained significant attention. In our research, we conducted indoor hydroponic experiments to examine the impacts of lanthanum (La) on the growth and enrichment capacity of Solanum nigrum L. (S. nigrum). S. nigrum was cultivated in 10 mg·L-1 of cadmium (Cd), 25 mg·L-1 of lead (Pb), and a mixture of both (5 mg·L-1 Cd + 15 mg·L-1 Pb). Additionally, S. nigrum were subjected to foliar spray or hydroponic supplementation of La(III). The treatment with La(III) significantly increased total fresh weight by 17.82 % to 42.20 %, compared to the treatment without La(III). Furthermore, La(III) facilitated the endocytosis of roots and enhanced Cd2+ flux ranging from 15.64 % to 75.99 % when compared to the treatment without La(III). Foliar and hydroponic application of La(III) resulted in an increase in the translocation factors (TF) in plants of Cd and Pb compared to treatments without La(III). These findings can offer valuable insights into the potential of La(III) to enhance the phytoremediation of soil or wastewater polluted with compounds.


Assuntos
Metais Pesados , Poluentes do Solo , Solanum nigrum , Cádmio/análise , Lantânio , Chumbo/toxicidade , Biodegradação Ambiental , Águas Residuárias , Poluentes do Solo/análise , Metais Pesados/análise , Solo/química , Endocitose
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