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1.
Sensors (Basel) ; 24(12)2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38931538

RESUMEN

A thiourea-based colorimetric sensor incorporating polyethyleneimine (PEI) and chromophoric nitrophenyl groups was synthesized and utilized for detecting various anions. Structural characterization of the sensor was accomplished using FTIR and 1H-NMR spectroscopy. The sensor's interactions and colorimetric recognition capabilities with different anions, including CI-, Br-, I-, F-, NO3-, PF6-, AcO-, H2PO4-, PO43-, and SO42-, were investigated via visual observation and UV/vis spectroscopy. Upon adding SO42-, F-, and AcO- anions, the sensor exhibited distinct color changes from colorless to yellow and yellowish, while other anions did not induce significant color alterations. UV/vis spectroscopic titration experiments conducted in a DMSO/H2O solution (9:1 volume ratio) demonstrated the sensor's selectivity toward SO42-, F-, and AcO-. The data revealed that the formation of the main compounds and anion complexes was mediated by hydrogen bonding, leading to signal changes in the nitrophenyl thiourea-modified PEI spectrum.

2.
Environ Res ; 220: 115236, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36621545

RESUMEN

Extensive global glacial retreats are threatening cryosphere ecosystem functioning and the associated biota in glacier-fed water systems. Understanding multi-group biodiversity distributions and compositional variation across diverse but hydrologically linked habitats under varying glacial influences will help explain the mechanisms underlying glacial community organization and ecosystem processes. However, such data are generally lacking due to the difficulty of obtaining biodiversity information across wide taxonomic ranges. Here, we used a multi-marker environmental DNA metabarcoding approach to simultaneously investigate the spatial patterns of community compositions and assembly mechanisms of four taxonomic groups (cyanobacteria, diatoms, invertebrates, and vertebrates) along the flowpaths of a tributary of Lake Nam Co on the Tibetan Plateau-from its glacier headwaters, through its downstream river and wetlands, to its estuary. We detected 869 operational taxonomic units: 119 cyanobacterial, 395 diatom, 269 invertebrate, and 86 vertebrate. Taxonomic richnesses consistently increased from upstream to downstream, and although all groups showed community similarity distance decay patterns, the trend for vertebrates was the weakest. Cyanobacteria, diatom, and invertebrate community compositions were significantly correlated with several environmental factors, while the vertebrate community was only correlated with waterway width. Variation partitioning analysis indicated that varying extents of environmental conditions and spatial factors affected community organizations for different groups. Furthermore, stochastic processes contributed prominently to the microorganisms' community assembly (Sloan's neutral model R2 = 0.77 for cyanobacteria and 0.73 for diatoms) but were less important for macroorganisms (R2 = 0.21 for invertebrates and 0.15 for vertebrates). That trend was further substantiated by modified stochasticity ratio analyses. This study provides the first holistic picture of the diverse biotic communities residing in a series of hydrologically connected glacier-influenced habitats. Our results both uncovered the distinct mechanisms that underlie the metacommunity organizations of different glacial organisms and helped comprehensively predict the ecological impacts of the world's melting glaciers.


Asunto(s)
Cianobacterias , Ecosistema , Animales , Tibet , Biodiversidad , Invertebrados
3.
Curr Genomics ; 23(6): 400-411, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-37920557

RESUMEN

Background: The white-backed planthopper (WBPH), Sogatella furcifera, causes great damage to many crops (mainly rice) by direct feeding or transmitting plant viruses. The previous genome assembly was generated by second-generation sequencing technologies, with a contig N50 of only 51.5 kb, and contained a lot of heterozygous sequences. Methods: We utilized third-generation sequencing technologies and Hi-C data to generate a high-quality chromosome-level assembly. We also provide a large amount of transcriptome data for full-length transcriptome analysis and gender differential expression analysis. Results: The final assembly comprised 56.38 Mb, with a contig N50 of 2.20 Mb and a scaffold N50 of 45.25 Mb. Fourteen autosomes and one X chromosome were identified. More than 99.5% of the assembled bases located on the 15 chromosomes. 95.9% of the complete BUSCO Hemiptera genes were detected in the final assembly and 16,880 genes were annotated. 722 genes were relatively highly expressed in males, while 60 in the females. Conclusion: The integrated genome, definite sex chromosomes, comprehensive transcriptome profiles, high efficiency of RNA interference and short life cycle substantially made WBPH an efficient research object for functional genomics.

4.
Heart Vessels ; 38(8): 1028-1034, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36941459

RESUMEN

Perioperative and short/mid-term survival rates of dialysis-dependent patients with end-stage renal disease (ESRD), who undergo coronary artery bypass grafting (CABG), and the factors influencing mortality are not well evaluated In China. We retrospectively analyzed the perioperative and postoperative 1-, 3-, and 5-year survival rates of 53 dialysis-dependent ESRD patients who underwent CABG, and compared the factors related to perioperative mortality and all-cause mortality during the postoperative follow-up. Survival rates were expressed as Kaplan-Meier survival curves, and factors influencing the follow-up survival rates were analyzed using the log rank (Mantel-Cox) test. There were eight perioperative deaths, resulting in 15.1% mortality. Intraoperative intra-aortic balloon pump use (P = 0.01), advanced age (P = 0.0027), and high EuroSCORE II score (P = 0.047) were associated with increased perioperative mortality. Forty-five discharged patients were followed from 2 months to 10 years (median, 4.2 years) postoperatively. There were 19 all-cause deaths, including 10 cardiac deaths (10/19, 52.6%). Comparisons between groups indicated that the presence of peripheral artery disease (PAD) increased mortality during follow-up (P = 0.025); 1-, 3-, and 5-year survival rates were 93.3, 79.5, and 66.8%, respectively. The results of the long-rank analysis indicated that the presence of PAD was a risk factor for postoperative survival (log rank χ2 = 4.543; P = 0.033). Dialysis-dependent patients with ESRD had high perioperative mortality and unsatisfactory short- and medium-term survival after CABG. PAD was a risk factor affecting patients' postoperative survival. Multidisciplinary teamwork is needed to enhance postoperative management and reduce complications, to improve postoperative survival in these patients.


Asunto(s)
Enfermedad de la Arteria Coronaria , Fallo Renal Crónico , Humanos , Diálisis Renal , Estudios Retrospectivos , Resultado del Tratamiento , Puente de Arteria Coronaria/métodos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Factores de Riesgo , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología
5.
Proc Natl Acad Sci U S A ; 117(19): 10414-10421, 2020 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-32350143

RESUMEN

The rise of oxygen on the early Earth about 2.4 billion years ago reorganized the redox cycle of harmful metal(loids), including that of arsenic, which doubtlessly imposed substantial barriers to the physiology and diversification of life. Evaluating the adaptive biological responses to these environmental challenges is inherently difficult because of the paucity of fossil records. Here we applied molecular clock analyses to 13 gene families participating in principal pathways of arsenic resistance and cycling, to explore the nature of early arsenic biogeocycles and decipher feedbacks associated with planetary oxygenation. Our results reveal the advent of nascent arsenic resistance systems under the anoxic environment predating the Great Oxidation Event (GOE), with the primary function of detoxifying reduced arsenic compounds that were abundant in Archean environments. To cope with the increased toxicity of oxidized arsenic species that occurred as oxygen built up in Earth's atmosphere, we found that parts of preexisting detoxification systems for trivalent arsenicals were merged with newly emerged pathways that originated via convergent evolution. Further expansion of arsenic resistance systems was made feasible by incorporation of oxygen-dependent enzymatic pathways into the detoxification network. These genetic innovations, together with adaptive responses to other redox-sensitive metals, provided organisms with novel mechanisms for adaption to changes in global biogeocycles that emerged as a consequence of the GOE.


Asunto(s)
Adaptación Biológica/genética , Arsénico/metabolismo , Oxígeno/metabolismo , Adaptación Biológica/fisiología , Atmósfera , Evolución Biológica , Planeta Tierra , Evolución Planetaria , Fósiles , Oxidación-Reducción
6.
Phytother Res ; 37(4): 1260-1273, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37041670

RESUMEN

Lung cancer is the leading cause of cancer-related death. In particular, non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancer cases. Due to tumor resistance and the toxicity of chemotherapeutic agents, it is increasingly critical to discover novel, potent antitumorigenic drugs for treating NSCLC. Lutein, a carotenoid, has been reported to exert toxic effects on cells in several tumor types. However, the detailed functions and underlying mechanisms of lutein in NSCLC remain elusive. The present study showed that lutein significantly and dose-dependently inhibited cell proliferation, arrested the cell cycle at the G0/G1 phase, and induced apoptosis in NSCLC cells. RNA-sequencing analysis revealed that the p53 signaling pathway was the most significantly upregulated in lutein-treated A549 cells. Mechanistically, lutein exerted antitumorigenic effects by inducing DNA damage and subsequently activating the ATR/Chk1/p53 signaling pathway in A549 cells. In vivo, lutein impeded tumor growth in mice and prolonged their survival. In conclusion, our findings demonstrate the antitumorigenic potential of lutein and reveal its molecular mechanism of action, suggesting that lutein is a promising candidate for clinical NSCLC treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Animales , Ratones , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Luteína/metabolismo , Luteína/farmacología , Luteína/uso terapéutico , Proteína p53 Supresora de Tumor/metabolismo , Línea Celular Tumoral , Transducción de Señal
7.
Mol Ecol ; 31(20): 5132-5164, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35972241

RESUMEN

Vast global declines of freshwater and marine fish diversity and population abundance pose serious threats to both ecosystem sustainability and human livelihoods. Environmental DNA (eDNA)-based biomonitoring provides robust, efficient, and cost-effective assessment of species occurrences and population trends in diverse aquatic environments. Thus, it holds great potential for improving conventional surveillance frameworks to facilitate fish conservation and fisheries management. However, the many technical considerations and rapid developments underway in the eDNA arena can overwhelm researchers and practitioners new to the field. Here, we systematically analysed 416 fish eDNA studies to summarize research trends in terms of investigated targets, research aims, and study systems, and reviewed the applications, rationales, methodological considerations, and limitations of eDNA methods with an emphasis on fish and fisheries research. We highlighted how eDNA technology may advance our knowledge of fish behaviour, species distributions, population genetics, community structures, and ecological interactions. We also synthesized the current knowledge of several important methodological concerns, including the qualitative and quantitative power eDNA has to recover fish biodiversity and abundance, and the spatial and temporal representations of eDNA with respect to its sources. To facilitate ecological applications implementing fish eDNA techniques, recent literature was summarized to generate guidelines for effective sampling in lentic, lotic, and marine habitats. Finally, we identified current gaps and limitations, and pointed out newly emerging research avenues for fish eDNA. As methodological optimization and standardization improve, eDNA technology should revolutionize fish monitoring and promote biodiversity conservation and fisheries management that transcends geographic and temporal boundaries.


Asunto(s)
ADN Ambiental , Animales , Biodiversidad , Código de Barras del ADN Taxonómico , ADN Ambiental/genética , Ecosistema , Monitoreo del Ambiente/métodos , Peces/genética , Humanos , Caza
8.
Biochem Genet ; 60(1): 223-240, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34169384

RESUMEN

This study combined with bioinformatics analysis and investigated the expression pattern of miR-181b-5p, as well as explored its role and mechanism in cholangiocarcinoma (CCA or CHOL). Several bioinformatics databases were used to analyze the expression of miR-181b and the enrichment of miR-181b in biological activities and biological pathways in CCA. The RT-qPCR analysis was used to examine the expression levels of miR-181b-5p. A receiver operation characteristics (ROC) curve analysis and the Kaplan-Meier survival assay were conducted to validate the diagnostic and prognostic implication of miR-181b-5p. Cell experiments were used to explore the possible functional role of miR-181b-5p in CCA progression. The bioinformatics assay was used to predict the target gene of miR-181b-5p and Western blot was used to confirm the related signaling pathway. The bioinformatics analysis results suggest that miR-181b-5p was highly expressed in cholangiocarcinoma and its expression was negatively related to PARK2 expression in CCA tissues. miR-181b-5p expression in the serum and tissues was upregulated and associated with lymph node metastasis and TNM stage. Increased expression of miR-181b-5p had relatively high diagnostic accuracy and showed poor prognosis in CCA patients. In addition, miR-181b-5p overexpression enhanced cell proliferation, migration, and invasion by targeting PARK2. Overexpression of miR-181b-5p activated the PI3K/AKT signaling pathway, while knockdown of miR-181b-5p suppressed the signaling pathway. Increased expression of miR-181b-5p in CCA may be a potential diagnostic or/and prognostic indicator for CCA patients. The present data indicated miR-181b-5p acted as an oncogene in CCA through promoting tumor cell proliferation, migration, and invasion of CCA via the PTEN/PI3K/AKT signaling pathway by targeting PARK2, which might be a promising therapeutic target or biomarker for CCA.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , MicroARNs , Ubiquitina-Proteína Ligasas/genética , Neoplasias de los Conductos Biliares/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Colangiocarcinoma/genética , Humanos , MicroARNs/genética , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
9.
Ecotoxicol Environ Saf ; 247: 114229, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36306614

RESUMEN

Although the phytotoxicity of graphene-based materials has been investigated extensively, the effects of different graphene-based materials on nutrient uptake in plants remain unclear. Here, we analyzed the differences in phytotoxicity between single-layer graphene oxide (sGO) and multi-layer graphene oxide (mGO) by analyzing the growth status and nitrate (NO3-) accumulation in wheat plants at 0, 100, 200, 400, and 800 mg L-1 graphene oxide supply. Both sGO and mGO displayed concentration-dependent inhibitory effects on biomass, root length, number of lateral roots, and nitrogen (N) nutrient status. Treatment with 400 mg L-1 sGO caused 0.9-, 1.3-, and 1-fold higher reductions in NO3--N, assimilated N, and total N concentrations in roots, respectively, than mGO treatment. Analysis of root oxidative stress and in situ NO3- uptake revealed that sGO caused more significant damage to the root tip and a lower NO3- net influx rate than mGO. In addition, the expression of NO3- transporter (NRT) genes in roots, including NRT1.5, NRT2.1, NRT2.2, NRT2.3, and NRT2.4, under sGO treatment were lower than those under mGO treatment. Overall, sGO treatment induced a more severe inhibitory effect on root growth and NO3- uptake and accumulation than mGO treatment, accompanied by significant suppression of the expression of NRTs in sGO-treated roots. This study provides a physiological and molecular basis for studying the phytotoxic effects of various sizes of graphene oxide.


Asunto(s)
Grafito , Triticum , Triticum/metabolismo , Nitratos/metabolismo , Grafito/metabolismo , Raíces de Plantas/metabolismo , Óxido de Magnesio , Nitrógeno/metabolismo
10.
J Asian Nat Prod Res ; : 1-7, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35672871

RESUMEN

Two undescribed stilbenoid diglycosides, dendrosonside A and dendrosonside B (1 and 2), were isolated from the stems of Dendrobium 'Sonia'. Their structures were elucidated based on 1 D/2D NMR and HRESIMS. The glycosyls contained in the two isolates were determined as D-glucose by acid hydrolysis and GC-MS analyses. In addition, 1 and 2 were further tested for the inhibition of nitric oxide production.

11.
Entropy (Basel) ; 24(10)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37420355

RESUMEN

As a multi-carrier modulation technique, a high peak-to-average power ratio (PAPR) is a common issue suffered by orthogonal frequency division multiplexing with index modulation (OFDM-IM) due to its system structure. High PAPR may cause signal distortion, which affects correct symbol transmission. This paper tries to inject dither signals to the inactive (idle) sub-carriers, which is a unique transmission structure of OFDM-IM, to reduce PAPR. Unlike the previous works, which utilize all idle sub-carriers, the proposed PAPR reduction scheme utilizes selected partial sub-carriers. This method performs well in terms of bit error rate (BER) performance and energy efficiency, which are obvious drawbacks of the previous PAPR reduction works due to the introduction of dither signals. In addition, in this paper, phase rotation factors are combined with the dither signals to compensate for the PAPR reduction performance degradation due to the insufficient use of partial idle sub-carriers. Moreover, an energy detection scheme is designed and proposed in this paper in order to distinguish the index of phase rotation factor used for transmission. It is shown by extensive simulation results that the proposed hybrid PAPR reduction scheme is able to implement an impressive PAPR reduction performance among existing dither signa-based schemes as well as classical distortion-less PAPR reduction schemes. In addition, the proposed method obtains better error performance and energy efficiency than that of the previous works. At the error probability 10-4, the proposed method can achieve around 5 dB gain compared to the conventional dither signal-based schemes.

12.
Appl Environ Microbiol ; 87(20): e0138321, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34378947

RESUMEN

Arsenic (As) metabolism genes are generally present in soils, but their diversity, relative abundance, and transcriptional activity in response to different As concentrations remain unclear, limiting our understanding of the microbial activities that control the fate of an important environmental pollutant. To address this issue, we applied metagenomics and metatranscriptomics to paddy soils showing a gradient of As concentrations to investigate As resistance genes (ars) including arsR, acr3, arsB, arsC, arsM, arsI, arsP, and arsH as well as energy-generating As respiratory oxidation (aioA) and reduction (arrA) genes. Somewhat unexpectedly, the relative DNA abundances and diversities of ars, aioA, and arrA genes were not significantly different between low and high (∼10 versus ∼100 mg kg-1) As soils. Compared to available metagenomes from other soils, geographic distance rather than As levels drove the different compositions of microbial communities. Arsenic significantly increased ars gene abundance only when its concentration was higher than 410 mg kg-1. In contrast, metatranscriptomics revealed that relative to low-As soils, high-As soils showed a significant increase in transcription of ars and aioA genes, which are induced by arsenite, the dominant As species in paddy soils, but not arrA genes, which are induced by arsenate. These patterns appeared to be community wide as opposed to taxon specific. Collectively, our findings advance understanding of how microbes respond to high As levels and the diversity of As metabolism genes in paddy soils and indicated that future studies of As metabolism in soil or other environments should include the function (transcriptome) level. IMPORTANCE Arsenic (As) is a toxic metalloid pervasively present in the environment. Microorganisms have evolved the capacity to metabolize As, and As metabolism genes are ubiquitously present in the environment even in the absence of high concentrations of As. However, these previous studies were carried out at the DNA level; thus, the activity of the As metabolism genes detected remains essentially speculative. Here, we show that the high As levels in paddy soils increased the transcriptional activity rather than the relative DNA abundance and diversity of As metabolism genes. These findings advance our understanding of how microbes respond to and cope with high As levels and have implications for better monitoring and managing an important toxic metalloid in agricultural soils and possibly other ecosystems.


Asunto(s)
Arsénico/metabolismo , Genes Arqueales , Genes Bacterianos , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Archaea/genética , Archaea/metabolismo , Arsénico/análisis , Bacterias/genética , Bacterias/metabolismo , Biodegradación Ambiental , Metales Pesados/análisis , Oryza , ARN Ribosómico 16S , Contaminantes del Suelo/análisis
13.
BMC Cancer ; 21(1): 1170, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34724907

RESUMEN

BACKGROUND: The prognosis of patients with gastrointestinal stromal tumors (GISTs) is generally evaluated at the time of diagnosis but does not reflect the survival dynamics of patients in the future. Therefore, the purpose of this article was to evaluate the conditional survival (CS) of Chinese patients with GISTs after radical resection. METHODS: This retrospective study included 451 patients who underwent radical surgery for GISTs. A Cox proportional hazard model was used to evaluate the prognostic factors of disease-free survival (DFS). The 3-year conditional DFS (CDFS3) of patients who survived for x years was expressed as CDFS3=DFS(x + 3)/DFS(x). RESULTS: The traditional 3-year DFS rate decreased gradually from 94.0% at 3 years to 77.3% at 7 years, while the CDFS3 rate increased from 94.0 to 95.2% over the survival time of the patients. In addition, classic clinicopathological prognostic factors had different effects on CDFS3, with changes observed in survival time, but these effects were only slight or moderate (|d|<0.5). Although multivariate analysis showed that age, sex, mitotic index and tumor rupture were independent risk factors for DFS at baseline, all adverse prognostic factors, except for the mitotic index, lost their predictive significance at 5 years after operation. When the Modified NIH criteria were included, the risk staging was found to be an independent risk factor for recurrence or death. Time-dependent Cox regression analysis showed that the modified NIH criteria independently affected the recurrence or death of GIST patients within 2 years after operation. CONCLUSION: CS provides detailed dynamic survival information about Chinese patients with primary resected GISTs. The mitotic index is of great clinical significance for the monitoring and follow-up of patient populations with a high risk of tumor recurrence or death until 5 years after surgery.


Asunto(s)
Tumores del Estroma Gastrointestinal/mortalidad , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , China/epidemiología , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Tumores del Estroma Gastrointestinal/cirugía , Humanos , Masculino , Persona de Mediana Edad , Índice Mitótico , Análisis Multivariante , Recurrencia Local de Neoplasia/mortalidad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores Sexuales , Factores de Tiempo , Carga Tumoral , Adulto Joven
14.
Pharmacol Res ; 161: 105111, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33065284

RESUMEN

Macrophages, a type of myeloid immune cell, play essential roles in fighting against pathogenic invasion and activating T cell-mediated adaptive immune responses. As a major constituent of the tumor microenvironment (TME), macrophages play a complex role in tumorigenesis and tumor progression. They can inhibit tumor growth by releasing proinflammatory cytokines and exerting cytotoxic activities but principally contribute to tumor progression by promoting tumor proliferation, angiogenesis, and metastasis. The tumor-promoting hallmarks of macrophages have aroused widespread interest in targeting tumor-associated macrophages (TAMs) for cancer immunotherapy. Increasing preclinical and clinical studies suggest that TAMs are a promising target for cancer immunotherapy. To date, TAM-targeted therapeutic strategies have mainly been divided into two kinds: inhibiting pro-tumor TAMs and activating anti-tumor TAMs. We reviewed the heterogeneous and plastic characteristics of macrophages in the TME and the feasible strategies to target TAMs in cancer immunotherapy and summarized the complementary effect of TAM-targeted therapy with traditional treatments or other immunotherapies.


Asunto(s)
Antineoplásicos/uso terapéutico , Inmunoterapia , Activación de Macrófagos/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Macrófagos Asociados a Tumores/efectos de los fármacos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Plasticidad de la Célula , Humanos , Terapia Molecular Dirigida , Neoplasias/inmunología , Neoplasias/metabolismo , Neoplasias/patología , Fenotipo , Transducción de Señal , Microambiente Tumoral , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo
15.
Environ Microbiol ; 21(1): 182-196, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30325092

RESUMEN

Little is known about microbial communities in the Ganges River, India and how they respond to intensive anthropogenic inputs. Here we applied shotgun metagenomics sequencing to study microbial community dynamics and function in planktonic samples collected along an approximately 700 km river transect, including urban cities and rural settings in upstream waters, before and after the monsoon rainy season. Our results showed that 11%-32% of the microbes represented terrestrial, sewage and human inputs (allochthonous). Sewage inputs significantly contributed to the higher abundance, by 13-fold of human gut microbiome (HG) associated sequences and 2-fold of antibiotic resistance genes (ARGs) in the Ganges relative to other riverine ecosystems in Europe, North and South America. Metagenome-assembled genome sequences (MAGs) representing allochthonous populations were detectable and tractable across the river after 1-2 days of (downstream) transport (> 200 km apart). Only approximately 8% of these MAGs were abundant in U.S. freshwater ecosystems, revealing distinct biodiversity for the Ganges. Microbial communities in the rainy season exhibited increased alpha-diversity and spatial heterogeneity and showed significantly weaker distance-decay patterns compared with the dry season. These results advance our understanding of the Ganges microbial communities and how they respond to anthropogenic pollution.


Asunto(s)
Biodiversidad , Monitoreo del Ambiente , Microbiota/fisiología , Ríos/microbiología , Estaciones del Año , Aguas del Alcantarillado , Ciudades , Farmacorresistencia Microbiana/genética , Humanos , India , Metagenoma , Metagenómica , Microbiota/genética , Plancton/microbiología
16.
Environ Microbiol ; 19(6): 2468-2482, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28447395

RESUMEN

As an analogue of phosphorus, arsenic (As) has a biogeochemical cycle coupled closely with other key elements on the Earth, such as iron, sulfate and phosphate. It has been documented that microbial genes associated with As biotransformation are widely present in As-rich environments. Nonetheless, their presence in natural environment with low As levels remains unclear. To address this issue, we investigated the abundance levels and diversities of aioA, arrA, arsC and arsM genes in estuarine sediments at low As levels across Southeastern China to uncover biogeographic patterns at a large spatial scale. Unexpectedly, genes involved in As biotransformation were characterized by high abundance and diversity. The functional microbial communities showed a significant decrease in similarity along the geographic distance, with higher turnover rates than taxonomic microbial communities based on the similarities of 16S rRNA genes. Further investigation with niche-based models showed that deterministic processes played primary roles in shaping both functional and taxonomic microbial communities. Temperature, pH, total nitrogen concentration, carbon/nitrogen ratio and ferric iron concentration rather than As content in these sediments were significantly linked to functional microbial communities, while sediment temperature and pH were linked to taxonomic microbial communities. We proposed several possible mechanisms to explain these results.


Asunto(s)
Arsénico/metabolismo , Bacterias/clasificación , Bacterias/metabolismo , Biotransformación/fisiología , Sedimentos Geológicos/microbiología , Bacterias/genética , Biotransformación/genética , China , Ambiente , ARN Ribosómico 16S/genética , Humedales
17.
J Pept Sci ; 23(6): 438-444, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28429419

RESUMEN

Prions are suspected as pathogen of the fatal transmissible spongiform encephalopathies. Strategies to access homogenous prion protein (PrP) are required to fully comprehend the molecular mechanism of prion diseases. However, the polypeptide fragments from PrP show a high tendency to form aggregates, which is a gigantic obstacle of protein synthesis and purification. In this study, murine prion sequence 90 to 230 that is the core three-dimensional structure domain was constructed from three segments murine PrP (mPrP)(90-177), mPrP(178-212), and mPrP(213-230) by combining protein expression, chemical synthesis and chemical ligation. The protein sequence 90 to 177 was obtained from expression and finally converted into the polypeptide hydrazide by chemical activation of a cysteine in the tail. The other two polypeptide fragments of the C-terminal were obtained by chemical synthesis, which utilized the strategies of isopeptide and pseudoproline building blocks to complete the synthesis of such difficult sequences. The three segments were finally assembled by sequentially using native chemical ligation. This strategy will allow more straightforward access to homogeneously modified PrP variants. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.


Asunto(s)
Ésteres/síntesis química , Péptidos/síntesis química , Proteínas Priónicas/síntesis química , Compuestos de Sulfhidrilo/síntesis química , Animales , Ésteres/química , Ratones , Conformación Molecular , Péptidos/química , Proteínas Priónicas/química , Compuestos de Sulfhidrilo/química
18.
Proc Natl Acad Sci U S A ; 111(1): 480-5, 2014 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-24367075

RESUMEN

Perception of time interval on the order of seconds is an essential component of cognition, but the underlying neural mechanism remains largely unknown. In rats trained to estimate time intervals, we found that many neurons in the medial prefrontal cortex (PFC) exhibited sustained spiking activity with diverse temporal profiles of firing-rate modulation during the time-estimation period. Interestingly, in tasks involving different intervals, each neuron exhibited firing-rate modulation with the same profile that was temporally scaled by a factor linearly proportional to the instructed intervals. The behavioral variability across trials within each task also correlated with the intertrial variability of the temporal scaling factor. Local cooling of the medial PFC, which affects neural circuit dynamics, significantly delayed behavioral responses. Thus, PFC neuronal activity contributes to time perception, and temporally scalable firing-rate modulation may reflect a general mechanism for neural representation of interval timing.


Asunto(s)
Potenciales de Acción/fisiología , Neuronas/metabolismo , Corteza Prefrontal/fisiología , Percepción del Tiempo , Animales , Conducta Animal , Electrofisiología , Aprendizaje , Masculino , Modelos Neurológicos , Actividad Motora/fisiología , Ratas , Ratas Long-Evans , Ratas Sprague-Dawley , Factores de Tiempo
19.
Environ Sci Technol ; 49(7): 4138-46, 2015 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-25738639

RESUMEN

Microbe-mediated arsenic (As) biotransformation in paddy soils determines the fate of As in soils and its availability to rice plants, yet little is known about the microbial communities involved in As biotransformation. Here, we revealed wide distribution, high diversity, and abundance of arsenite (As(III)) oxidase genes (aioA), respiratory arsenate (As(V)) reductase genes (arrA), As(V) reductase genes (arsC), and As(III) S-adenosylmethionine methyltransferase genes (arsM) in 13 paddy soils collected across Southern China. Sequences grouped with As biotransformation genes are mainly from rice rhizosphere bacteria, such as some Proteobacteria, Gemmatimonadales, and Firmicutes. A significant correlation of gene abundance between arsC and arsM suggests that the two genes coexist well in the microbial As resistance system. Redundancy analysis (RDA) indicated that soil pH, EC, total C, N, As, and Fe, C/N ratio, SO4(2-)-S, NO3(-)-N, and NH4(+)-N were the key factors driving diverse microbial community compositions. This study for the first time provides an overall picture of microbial communities involved in As biotransformation in paddy soils, and considering the wide distribution of paddy fields in the world, it also provides insights into the critical role of paddy fields in the As biogeochemical cycle.


Asunto(s)
Arseniato Reductasas/genética , Arsénico/metabolismo , Genes Bacterianos , Consorcios Microbianos , Oxidorreductasas/genética , Microbiología del Suelo , Arseniatos/metabolismo , Arsenitos/metabolismo , Bacterias/metabolismo , Biodegradación Ambiental , Biodiversidad , Biotransformación , China , Oryza , Rizosfera , Suelo/química , Contaminantes del Suelo/análisis
20.
Zhong Yao Cai ; 38(10): 2056-9, 2015 Oct.
Artículo en Zh | MEDLINE | ID: mdl-27254915

RESUMEN

OBJECTIVE: To study the different effects of crude Atractylodis Rhizoma and processed Atractylodis Rhizoma in healthy rats, in order to prove the traditional theory that the crude Atractylodis Rhizoma has dry effects and the dry effects can be weaken by processing. METHODS: Health rats had been orally administered with pure water, crude Atractylodis Rhizoma, processed Atractylodis Rhizoma and atropine. The concentration of AQP1 and AQP5 in submaxillary gland were measured by ELISA. Their index of submaxillary gland, hemorheology and moisture content of intestine were also measured. RESULTS: There were obvious differences of concentration of AQP1 and AQP5 in submaxillary gland, index of submaxillary gland, hemorheology and moisture content of intestine between the rats which had been orally administered crude Atractylodis Rhizoma and the rats administered processed Rhizoma Atractylodes. CONCLUSIONS: The dry effects of Atractylodis Rhizoma works on rats' moisture content of intestine, index of submaxillary gland and hemorheology. The dry effects can be weaken by processing.


Asunto(s)
Acuaporina 1/metabolismo , Acuaporina 5/metabolismo , Atractylodes/química , Hemorreología , Animales , Ensayo de Inmunoadsorción Enzimática , Mucosa Intestinal/metabolismo , Plantas Medicinales/química , Ratas , Rizoma/química , Glándula Submandibular/metabolismo
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