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1.
Microb Ecol ; 87(1): 59, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619730

RESUMEN

As one of the important biodiversity conservation areas in China, the ecosystem in the lower reaches of the Yarlung Zangbo River is fragile, and is particularly sensitive to global changes. To reveal the diversity pattern of phytoplankton, the metabarcode sequencing was employed in the Medog section of the lower reaches of the Yarlung Zangbo River during autumn 2019 in present study. The phytoplankton assemblies can be significantly divided into the main stem and the tributaries; there are significant differences in the phytoplankton biomass, alpha and beta diversity between the main stem and the tributaries. While both the main stem and the tributaries are affected by dispersal limitation, the phytoplankton assemblages in the entire lower reaches are primarily influenced by heterogeneous selection. Community dissimilarity and assembly process were significantly correlated with turbidity, electrical conductivity, and nitrogen nutrition. The tributaries were the main source of the increase in phytoplankton diversity in the lower reaches of the Yarlung Zangbo River. Such diversity pattern of phytoplankton in the lower reach may be caused by the special habitat in Medog, that is, the excessive flow velocity, and the significant spatial heterogeneity in physical and chemical factors between stem and tributaries. Based on the results and conclusions obtained in present study, continuous long-term monitoring is essential to assess and quantify the impact of global changes on phytoplankton.


Asunto(s)
Ecosistema , Ríos , Biodiversidad , Biomasa , Fitoplancton
2.
J Environ Manage ; 357: 120697, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38565031

RESUMEN

Global ecosystems are facing anthropogenic threats that affect their ecological functions and biodiversity. However, we still lack an understanding of how biodiversity can mediate the responses of ecosystems or communities to human disturbance across spatial gradients. Here, we examined how existing, spatial patterns of biodiversity influence the ecological effects of small hydropower plants (SHPs) on macroinvertebrates in river ecosystems. This study found that levels of biodiversity (e.g., number of species) can influence the degrees of its alterations by SHPs occurring along elevational gradients. The results of the study reveal that the construction of SHPs has various effects on biodiversity. For example, low-altitude areas with low biodiversity (species richness less than 12) showed a small increase in biodiversity compared to high-altitude areas (species richness more than 12) under SHP disturbances. The increases in the effective habitat area of the river segment could be a driver of the enhanced biodiversity in response to SHP effects. Changes in the numerically dominant species contributed to the overall level of community variation from disturbances. Location-specific strategies may mitigate the effects of SHPs and perhaps other disturbances.


Asunto(s)
Ecosistema , Ríos , Humanos , Biodiversidad , Altitud
3.
J Environ Manage ; 350: 119697, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38035504

RESUMEN

Lakes serve as vital reservoirs of dissolved organic matter (DOM) and play pivotal roles in biogeochemical carbon cycles. However, the sources and compositions of DOM in freshwater lakes and their potential effects on lake sediment carbon pools remain unclear. In this study, seven inflowing rivers in the Lake Taihu basin were selected to explore the potential effects of multi-source DOM inputs on the stability of the lake sediment carbon pool. The results showed the high concentrations of dissolved organic carbon in the Lake Taihu basin, accompanied by a high complexity level. Lignins constituted the majority of DOM compounds, surpassing 40% of the total, while the organic carbon content was predominantly composed of humic acids (1.02-3.01 g kg-1). The high amounts of lignin oxidative cleavage led to CHO being the main molecular structure in the DOM of the seven rivers. The carbon constituents within the sediment carbon reservoir exhibited a positive correlation with dissolved CH4 and CO2, with a notable emphasis on humic acid and dissolved CH4 (R2 = 0.86). The elevated concentration of DOM, coupled with its intricate composition, contributed to the increases in dissolved greenhouse gases (GHGs). Experiments showed that the mixing of multi-source DOM can accelerate the organic carbon mineralization processes. The unit carbon emission efficiency was highest in the mixed group, reaching reached 160.9 µmol∙Cg-1, which also exhibited a significantly different carbon pool. The mixed decomposition of DOM from different sources influenced the roles of the lake carbon pool as source and sink, indicating that the multi-source DOM of this lake basin was a potential driving factor for increased carbon emissions. These findings have improved our understanding of the sources and compositions of DOM in lake basins and revealed their impacts on carbon emissions, thereby providing a theoretical basis for improving assessments of lake carbon emissions.


Asunto(s)
Materia Orgánica Disuelta , Gases de Efecto Invernadero , Lagos/análisis , Lagos/química , Carbono , Ríos , Sustancias Húmicas/análisis , China
4.
Immunol Rev ; 290(1): 24-38, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31355488

RESUMEN

The fact that a subset of human cancers showed evidence for a spontaneous adaptive immune response as reflected by the T cell-inflamed tumor microenvironment phenotype led to the search for candidate innate immune pathways that might be driving such endogenous responses. Preclinical studies indicated a major role for the host STING pathway, a cytosolic DNA sensing pathway, as a proximal event required for optimal type I interferon production, dendritic cell activation, and priming of CD8+ T cells against tumor-associated antigens. STING agonists are therefore being developed as a novel cancer therapeutic, and a greater understanding of STING pathway regulation is leading to a broadened list of candidate immune regulatory targets. Early phase clinical trials of intratumoral STING agonists are already showing promise, alone and in combination with checkpoint blockade. Further advancement will derive from a deeper understanding of STING pathway biology as well as mechanisms of response vs resistance in individual cancer patients.


Asunto(s)
Antineoplásicos/uso terapéutico , Proteínas de la Membrana/agonistas , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Biomarcadores , Terapia Combinada , Proteínas de Unión al ADN/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Inmunomodulación/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Neoplasias/diagnóstico , Neoplasias/inmunología , Resultado del Tratamiento
5.
BMC Ophthalmol ; 22(1): 219, 2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35562683

RESUMEN

BACKGROUND: To detect the superficial and buried optic disc drusen (ODD) with swept-source optical coherence tomography (SS-OCT). METHODS: Retrospective cross-sectional study. Twenty patients (age 18-74 years) diagnosed with ODD via B-scan ultrasonography were analysed. All patients underwent color fundus photography (CFP), B-scan ultrasonography, fundus autofluorescence (FAF), and SS-OCT. We defined each hyporeflective signal mass of SS-OCT as an ODD, recorded its location and relationship with Bruch's membrane opening (BMO), and other ophthalmic imaging characteristics. RESULTS: Twenty (33 eyes) patients had 54 ODDs in all, except one eye did not show abnormal optic disc findings on SS-OCT. We classified ODD into three categories: ODD above BMO, ODD across BMO, and ODD below BMO. The ODDs across BMO were the largest, followed by ODDs below BMO, and those above BMO. The location of the ODDs: One (1.9%) was in the border tissue of Elschnig, 6 (11.1%) might span across the lamina cribrosa, 16 (29.6%) were above BMO located in the neuroepithelial layer, 9 (16.7%) spanned across BMO located near the center of the optic disc, 18 (33.3%) were below BMO located near the center of the optic disc, 4 (7.4%) were below BMO located within the optic disc rim. When the anterior margin was ≥ 100 µm from the BMO, clear autofluorescence could be seen. CONCLUSION: Multimodal imaging provided a deeper understanding of ODD. SS-OCT illustrated more details about the relationship between the posterior surface of ODD, BMO and the lamina cribrosa.


Asunto(s)
Drusas del Disco Óptico , Adolescente , Adulto , Anciano , Lámina Basal de la Coroides , Estudios Transversales , Humanos , Persona de Mediana Edad , Fibras Nerviosas , Drusas del Disco Óptico/diagnóstico por imagen , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Adulto Joven
6.
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
7.
Int Ophthalmol ; 41(4): 1291-1299, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33389425

RESUMEN

PURPOSE: To evaluate the performance of an AI-based diabetic retinopathy (DR) grading model in real-world community clinical setting. METHODS: Participants with diabetes on record in the chosen community were recruited by health care staffs in a primary clinic of Zhengzhou city, China. Retinal images were prospectively collected during December 2018 and April 2019 based on intent-to-screen principle. A pre-validated AI system based on deep learning algorithm was deployed to screen DR graded according to the International Clinical Diabetic Retinopathy scale. Kappa value of DR severity, the sensitivity, specificity of detecting referable DR (RDR) and any DR were generated based on the standard of the majority manual grading decision of a retina specialist panel. RESULTS: Of the 193 eligible participants, 173 (89.6%) were readable with at least one eye image. Mean [SD] age was 69.3 (9.0) years old. Total of 321 eyes (83.2%) were graded both by AI and the specialist panel. The κ value in eye image grading was 0.715. The sensitivity, specificity and area under curve for detection of RDR were 84.6% (95% CI: 54.6- 98.1%), 98.0% (95% CI: 94.3-99.6%) and 0.913 (95% CI: 0.797-1.000), respectively. For detection of any DR, the upper indicators were 90.0% (95% CI: 68.3-98.8), 96.6% (95% CI: 92.1-98.9) and 0.933 (95% CI: 0.933-1.000), respectively. CONCLUSION: The AI system showed relatively good consistency with ophthalmologist diagnosis in DR grading, high specificity and acceptable sensitivity for identifying RDR and any DR. TRANSLATIONAL RELEVANCE: It is feasible to apply AI-based DR screening in community. PRECIS: Deployed in community real-world clinic setting, AI-based DR screening system showed high specificity and acceptable sensitivity in identifying RDR and any DR. Good DR diagnostic consistency was found between AI and manual grading. These prospective evidences were essential for regulatory approval.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Anciano , Inteligencia Artificial , China/epidemiología , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Humanos , Tamizaje Masivo , Estudios Prospectivos
8.
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
9.
Retina ; 40(11): 2119-2126, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31851049

RESUMEN

PURPOSE: To investigate the relationship between posterior staphyloma and dome-shaped macula (DSM) in highly myopic eyes. METHODS: The clinical data were collected from patients with high myopia: diopter, best-corrected visual acuity, axial length, fundus images, optical coherence tomography, and 3D magnetic resonance imaging. A DSM was defined as a convex curvature of the macula in one or both of the vertical and horizontal optical coherence tomography scans. The relationship between DSM and posterior staphyloma was evaluated. RESULTS: A total of 123 eyes were included. Dome-shaped macula was found in 18 eyes (14.63%). Twelve eyes with DSM had positive 3D magnetic resonance imaging findings. Nine eyes had horizontal oval-shaped dome, and a band-shaped inward convexity that extended horizontally from the optic disc through the fovea could be seen. Three eyes had round dome, and 3D magnetic resonance imaging showed a round inward convexity of the macular area. Five inward convexities were the border of multiple staphylomas, five were the boundary of one staphyloma, and two were within a single staphyloma. CONCLUSION: The formation of highly myopic DSM is related to the morphological change of the entire posterior segment.


Asunto(s)
Mácula Lútea/diagnóstico por imagen , Miopía Degenerativa/complicaciones , Segmento Posterior del Ojo/diagnóstico por imagen , Enfermedades de la Retina/diagnóstico por imagen , Enfermedades de la Esclerótica/diagnóstico por imagen , Adulto , Anciano , Longitud Axial del Ojo/patología , Dilatación Patológica , Femenino , Humanos , Mácula Lútea/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Segmento Posterior del Ojo/patología , Enfermedades de la Retina/etiología , Enfermedades de la Esclerótica/etiología , Tomografía de Coherencia Óptica , Agudeza Visual/fisiología
10.
Int Immunol ; 30(7): 311-318, 2018 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-29939266

RESUMEN

B-1 cells are innate-like B-cell population and produce natural antibodies that contribute to the first line of host defense. There are two subsets of B-1 cells: B-1a and B-1b. B-1a cells are the main producer of poly-reactive and autoreactive natural IgM antibodies, whereas B-1b cells can respond specifically to T-cell-independent antigens. Despite the functional significance of B-1a and B-1b cells, little information is available about what regulates the development of these two subsets. We found that Kelch-like protein 14 (KLHL14) was expressed at high levels in B cells but only at low levels in a few non-lymphoid tissues. Although mice lacking KLHL14 died right after birth, the heterozygotes developed normally with no gross abnormalities by appearance. B-cell development in the bone marrow and maturation and activation in the spleen were not affected in the heterozygous mice. However, the number of peritoneal B-1a cells was significantly reduced while B-1b cells were increased in Klhl14 heterozygous mice compared with wild-type (WT) mice. Consistently, Rag1-/- mice reconstituted with Klhl14-/- fetal liver cells had a more severe reduction of B-1a and an increase of B-1b cells in the peritoneal cavity. KLHL14 did not affect the turnover or apoptosis of B-1a and B-1b cells in vivo. Moreover, Klhl14-/- fetal liver contained a similar proportion and absolute numbers of the B-1 progenitor cells as did WT fetal liver. These results suggest that KLHL14 promotes B-1a development in mice.


Asunto(s)
Subgrupos de Linfocitos B/citología , Subgrupos de Linfocitos B/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Subgrupos de Linfocitos B/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/deficiencia
11.
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
12.
Zhongguo Yi Liao Qi Xie Za Zhi ; 41(4): 255-258, 2017 Jul 30.
Artículo en Zh | MEDLINE | ID: mdl-29862783

RESUMEN

Amblyopia is the common disease in the children's growth. There are some disadvantages in traditional treatment to amblyopia, such as poor compliance, easily leading to the healthy eye eyesight problem, the poor recovery of binocular and stereoscopy vision, etc. This paper put forward a new individual amblyopia treatment system to solve these problems. It combined pattern reversal visual evoked potential (P_VEP) feedback and dichoptic training theory and then developed the EEG data acquisition and synchronized trigger circuit using and I/O data collecting card, realized the raw EEG signal real-time sampling, extracted VEP waveform from the raw EEG data by using digital filtering algorithm, average superposition algorithm and wavelet an lgorithm, finally, the latency and peak of P_VEP wave shape were accurately measured. This system also present an individual treatment solution based on dichoptic training model by searching and obtaining the best spatial frequency of the treatment training picture and combining with 3D display technology.


Asunto(s)
Algoritmos , Ambliopía/terapia , Potenciales Evocados Visuales , Niño , Humanos , Visión Binocular , Agudeza Visual
13.
Ann Hum Biol ; 41(3): 244-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24215563

RESUMEN

BACKGROUND: In view of their high level of variability, autosomal short tandem repeats (STRs) are very useful as markers in the disciplines of forensic and population genetics studies. AIM: To investigate the diversity distributions of allelic frequencies of 15 loci from a sample from the Chinese Xibe ethnic group in Liaoning. SUBJECTS AND METHODS: Fifteen STR loci for 150 unrelated Xibe individuals from Liaoning, China were amplified simultaneously in a fluorescence-based reaction using a 2720 Thermal cycler (ABI). Separation and detection of the amplified product were conducted with the Li-COR 4300 DNA Analyzer. RESULTS: In total, 117 alleles were observed, with the corresponding allele frequencies ranging from 0.001 to 0.507. D18S51 had the highest polymorphism (PIC = 0.840) among all 15 STR loci, whereas TPOX had the lowest (PIC = 0.590). The power of discrimination ranged from 0.801 for TH01 locus to 0.957 for D18S51 locus, whereas the power of exclusion ranged from a minimum 0.316 for TPOX locus to a maximum 0.720 for D21S11 locus. The phylogenetic tree established among worldwide populations showed that the Xibe population is far from other populations. CONCLUSION: Databases for the 15 STR loci will be useful for personal identification and paternity tests in the Xibe population and for the establishment of phylogenetic relationships between populations.


Asunto(s)
Etnicidad/genética , Frecuencia de los Genes , Repeticiones de Microsatélite , Polimorfismo Genético , China/etnología , Humanos , Reacción en Cadena de la Polimerasa
14.
Int Immunol ; 24(12): 751-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22855849

RESUMEN

Heat shock protein 90 (HSP90) is a molecular chaperone required for efficient antigen presentation and cross-presentation. In addition, HSP90 was recently reported to interact with and stabilize the activation-induced cytidine deaminase (AID) and plays a critical role in immunoglobulin gene hypermutation and class switch recombination. In mice and humans, there are two HSP90 isoforms, HSP90α and HSP90ß, but the in vivo role of each isoform remains largely unknown. Here we have analyzed humoral immune responses in HSP90α-deficient mice. We found that HSP90α deficiency did not affect AID protein expression. B cell development and maturation, as well as immunoglobulin gene hypermuation and class switch, occurred normally in HSP90α-deficient mice. However, antibody production to a T-dependent antigen was elevated in the mutant mice and this was associated with enhanced MHC class II antigen presentation to T helper cells by dendritic cells. Our results reveal a previously unidentified inhibitory role for HSP90α isoform in MHC class II antigen presentation and the humoral immune response. Along with our recent finding that HSP90α is required for antigen cross-presentation, these results suggest that HSP90α controls the balance of humoral and cellular immunity by dictating the fate of presentation of exogenous antigen.


Asunto(s)
Linfocitos B/inmunología , Proteínas HSP90 de Choque Térmico/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Presentación de Antígeno/genética , Antígenos/inmunología , Antígenos/metabolismo , Citidina Desaminasa/metabolismo , Proteínas HSP90 de Choque Térmico/genética , Humanos , Hibridomas , Inmunidad Humoral/genética , Cambio de Clase de Inmunoglobulina/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Hipermutación Somática de Inmunoglobulina/genética
15.
Sci Total Environ ; 904: 166316, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37591396

RESUMEN

Hydrated electrons (eaq-) exhibit rapid degradation of diverse persistent organic contaminants (OCs) and hold great promise as a formidable reducing agent in water treatment. However, the diverse structures of compounds exert different influences on the second-order rate constant of hydrated electron reactions (keaq-), while the same OCs demonstrate notable discrepancies in keaq- values across different pH levels. This study aims to develop machine learning (ML) models that can effectively simulate the intricate reaction kinetics between eaq- and OCs. Furthermore, the introduction of the pH variable enables a comprehensive investigation into the impact of ambient conditions on this process, thereby improving the practicality of the model. A dataset encompassing 701 keaq- values derived from 351 peer-reviewed publications was compiled. To comprehensively investigate compound properties, this study introduced molecular descriptor (MD), molecular fingerprint (MF), and the integration of both (MD + MF) as model variables. Furthermore, 60 sets of predictive models were established utilizing two variable screening methodologies (MLR and RF) and ten prominent algorithms. Through statistical parameter analysis, it was determined that descriptors combined with MD and MF, the RF screening method, and the symbolism algorithm exhibited the best predictive efficacy. Importantly, the combination of descriptor models exhibited significantly superior performance compared to individual MF and MD models. Notably, the optimal model, denoted as RF - (MF + MD) - LGB, exhibited highly satisfactory predictive results (R2tra = 0.967, Q2tra = 0.840, R2ext = 0.761). The mechanistic explanation study based on Shapley Additive Explanations (SHAP) values further elucidated the crucial influences of polarity, pH, molecular weight, electronegativity, carbon-carbon double bonds, and molecular topology on the degradation of OCs by eaq-. The proposed modeling approach, particularly the integration of MF and MD, alongside the introduction of pH, may furnish innovative ideas for advanced reduction or oxidation processes (ARPs/AOPs) and machine learning applications in other domains.

16.
Plant Divers ; 45(1): 45-53, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36876308

RESUMEN

Phyllosphere algae are common in tropical rainforests, forming visible biofilms or spots on plant leaf surfaces. However, knowledge of phyllosphere algal diversity and the environmental factors that drive that diversity is limited. The aim of this study is to identify the environmental factors that drive phyllosphere algal community composition and diversity in rainforests. For this purpose, we used single molecule real-time sequencing of full-length 18S rDNA to characterize the composition of phyllosphere microalgal communities growing on four host tree species (Ficus tikoua, Caryota mitis, Arenga pinnata, and Musa acuminata) common to three types of forest over four months at the Xishuangbanna Tropical Botanical Garden, Yunnan Province, China. Environmental 18S rDNA sequences revealed that the green algae orders Watanabeales and Trentepohliales were dominant in almost all algal communities and that phyllosphere algal species richness and biomass were lower in planted forest than in primeval and reserve rainforest. In addition, algal community composition differed significantly between planted forest and primeval rainforest. We also found that algal communities were affected by soluble reactive phosphorous, total nitrogen, and ammonium contents. Our findings indicate that algal community structure is significantly related to forest type and host tree species. Furthermore, this study is the first to identify environmental factors that affect phyllosphere algal communities, significantly contributing to future taxonomic research, especially for the green algae orders Watanabeales and Trentepohliales. This research also serves as an important reference for molecular diversity analysis of algae in other specific habitats, such as epiphytic algae and soil algae.

17.
Gene ; 863: 147287, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-36804852

RESUMEN

The little-known order Watanabeales currently includes 10 genera with Chlorella-like species that reproduce by unequal-sized autospores and are predominantly solitary or terrestrial. The taxonomic scheme of Watanabeales has only been primarily inferred by short and less informative rDNA phylogenetic analysis. In the present study, seven newly sequenced genomes and one reported chloroplast genome representing the existing major branches of Watanabeales were harvested to phylogenetically reconstruct this order and to further understand its evolution. All chloroplast genomes of Watanabeales ranging from 133 to 274 kb were circular mapping and lacked a quadripartite structure. The chloroplast genome size, GC content, number of introns, and length of intergenic region proportion of the Watanabeales showed consistent trends, with Calidiella yingdensis D201 and Kalinella pachyderma 2601 having the lowest and highest values, respectively, echoing the positive correlation between organismal size and genome size. Phylogenetic analysis of Watanabeales based on 76 protein-coding genes coupled with the establishment of various complex analytical methods determined the unique robust taxonomic scheme which was incongruent with rDNA. Comparative genomic analyses revealed that the chloroplast genomes of Watanabeales accounted for numerous complex rearrangements and inversions which indicated high cryptic diversity. Substitution rate estimation indicated that the chloroplast genomes of Watanabeales were under purifying selection and similar evolutionary pressure and supported the view that genus Symbiochloris should be excluded from Watanabeales. Our results enrich the chloroplast genome resources of Watanabeales, clarify the phylogenetic status of species within this order, and provide more reference information for subsequent taxonomic and phylogenetic study.


Asunto(s)
Chlorella , Genoma del Cloroplasto , Filogenia , Secuencia de Bases , ADN Ribosómico
18.
Zhonghua Yan Ke Za Zhi ; 48(10): 924-9, 2012 Oct.
Artículo en Zh | MEDLINE | ID: mdl-23302249

RESUMEN

OBJECTIVE: To analysis the clinical characteristics of corneal interface fluid syndrome (IFS). METHODS: This is a retrospective study. During Jun. 2007 to Oct. 2011. Eight cases (12 eyes) of IFS were diagnosed at Henan Eye Institute. The history and complete ophthalmic examination that include Slit-lamp examination, Slit-lamp photography, IOP, anterior segment OCT (AS-OCT), confocal microscopic exams were recorded. RESULTS: In total 8 cases (12 eyes), 4 cases were bilateral, 4 cases were unilateral. Six patients were male and 2 were female. The age of the patients ranged from 19 to 35 years. Post-lasik steroid-induced elevated IOP was 4 eyes in 2 patients. Primary open angle glaucoma was 4 eyes in 2 patients. 1 patient (1 eye) was Posner-Shlossman syndrome, 1 patient (1 eye) was pigmented glaucoma, 1 patient (1 eye) was post-lasik traumatic iritis. 1 patient (1 eye) got IFS after repeated flap reposition because of epithelium ingrowth. Slit-lamp exam indicated edematous corneal, lamellar haze, interface fluids accumulation. AS-OCT showed obvious interface dark area. Confocal microscopy exam showed edematous corneal flap, more oval and large keratocytes' nuclei but no inflammatory cells. CONCLUSIONS: IFS is a rare but serious complication after LASIK. The main causes are high intraocular pressure and/or dysfunction of corneal endothelium. Careful exam by slit-lamp may help diagnosis, and further AS-OCT and/or in vivo confocal microscopy exam will confirm it.


Asunto(s)
Edema Corneal , Adulto , Edema Corneal/diagnóstico , Edema Corneal/etiología , Femenino , Humanos , Queratomileusis por Láser In Situ/efectos adversos , Masculino , Estudios Retrospectivos , Adulto Joven
19.
Front Genet ; 13: 832814, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309139

RESUMEN

Purpose: X-linked juvenile retinoschisis (XLRS), caused by mutations in the RS1 gene, is an X-linked recessive inherited disease that typically involves both eyes in the first 2 decades of life. Recently, the phenotype heterogeneity of this condition has drawn increasing attention. We reported various phenotypes caused by RS1 gene mutations in eleven patients from ten Chinese families. Methods: Data on the medical history of the patients from ten Han families of central China were collected. Ophthalmic examinations including best-corrected visual acuity (BCVA), fundus photography, ultra-wide-angle sweep source optical coherence tomography (SS-OCT), and electroretinography (ERG) were performed. Adaptive optics (AO) images were acquired to evaluate the cone photoreceptor mosaic when applicable. Venous blood of the probands and their family members was collected, and DNA was subjected to sequencing based on next-generation sequencing with a custom-designed targeted gene panel PS400 for inherited retinal diseases. Validation was performed by Sanger sequencing and cosegregation. Pathogenicity was determined in accordance with the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Ten RS1 mutations, including eight missense mutations and two terminator mutations, were identified in 10 XLRS families. c.657C > A (p.C219X) was a novel mutation in this cohort. These patients showed a variety of clinical phenotypes, including fovea schisis, bullous retinoschisis, and macular or peripheral atrophy. Fifteen eyes of eight patients exhibited macular retinoschisis, and twelve eyes of seven patients exhibited peripheral retinoschisis. In addition, three patients showed asymmetrical fundus manifestations. Of importance, three patients without macular retinoschisis were misdiagnosed until genetic testing results were obtained. AO showed a decrease in cone density and loss of regularity in the cystic schisis macular of XLRS. Furthermore, the BCVA was associated with the photoreceptor inner segment and outer segment (IS/OS) thickness. Conclusion: With complicated clinical manifestations, a considerable portion of XLRS patients may present various phenotypes. It should be noted that asymmetry in fundus appearance in both eyes could lead to misdiagnosis easily. Thus, genetic testing is crucial for making a final diagnosis in those patients who are suspected of having amblyopia, bilateral or unilateral macular atrophy, or conditions presenting an asymmetric fundus appearance. In addition, the residual cone photoreceptor structure was critical for the maintenance of useful vision.

20.
J Ophthalmol ; 2021: 4853531, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628474

RESUMEN

PURPOSE: To analysis the multimodal imaging of a group of patients diagnosed clinically with atypical juvenile ocular toxocariasis (OT). METHODS: In this case series study, we examined 9 young patients diagnosed with atypical OT. Routine ophthalmological examinations, fundus photography, optical-coherence tomography (OCT), fluorescein angiography (FFA), and B-mode ultrasound were performed. A questionnaire was used to record whether the patients were newly diagnosed and whether they had a history of exposure to a cat and dog. Aqueous humor and serum samples were taken for serological tests. RESULTS: In all the patients, yellow-and-white dot-shaped lesions and perivascular white sheath were seen in the fundus. Heterogeneous changes including hyper-reflection in the disrupted neuroretina, hyper-reflection in the outer retinal layer, high-reflection mass on the surface of the neuroretina accompanied with reflective attenuation, and high-reflection mass involving the entire neuroretina or high-reflection mass in the vitreous body were noticed in OCT images. On FFA, seven of these patients (77.8%) showed leakage of fluorescein in the small- and medium-branch veins of the retina, and a "bristle-like" change indicated increased permeability of the vessels. B-mode ultrasound showed proliferative membranes and proliferative bands (33.3%), as well as spotted opacity in the vitreous (66.7%). The antibodies to Toxocara canis in the aqueous humor and serum were positive, and the Goldmann-Witmer coefficient was significantly increased in 6 out of 7 patients. CONCLUSIONS: Multimodality images are useful in the diagnosis of atypical juvenile OT, which could be easily overlooked and misdiagnosed.

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