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Fungi have been reported to be the dominant eukaryotic group in anoxic sub-seafloor sediments, but how fungi subsist in the anoxic sub-marine sedimental environment is rarely understood. Our previous study demonstrated that the fungus, Schizophyllum commune 20R-7-F01 isolated from a ~2 km sediment below the seafloor, can grow and produce primordia in the complete absence of oxygen with enhanced production of branched-chain amino acids (BCAAs), but the primordia cannot be developed into fruit bodies without oxygen. Here, we present the individual and synergistic effects of oxygen and BCAAs on the fruit-body development of this strain. It was found that the fungus required a minimum oxygen concentration of 0.5% pO2 to generate primordia and 1% pO2 to convert primordia into mature fruit body. However, if BCAAs (20 mM) were added to the medium, the primordium could be developed into fruit body at a lower oxygen concentration up to 0.5% pO2 where genes fst4 and c2h2 playing an important role in compensating oxygen deficiency. Moreover, under hypoxic conditions, the fungus showed an increase in mitochondrial number and initiation of auto-phagocytosis. These findings suggest that the fruit-body formation of S. commune may have multiple mechanisms, including energy and amino acid metabolism in response to oxygen concentrations.
Assuntos
Schizophyllum , Aminoácidos de Cadeia Ramificada , Sedimentos Geológicos , Crescimento e Desenvolvimento , Oxigênio/metabolismo , Schizophyllum/metabolismoRESUMO
We carried out an observational and experimental study to decipher how resource characteristics, in interaction with the predator's phenotype, constrain a fitness-determining performance measure, i.e. refuelling in a migrant bird. Two subspecies of red knot (Calidris canutus rogersi and C. c. piersmai) use northern Bohai Bay, Yellow Sea, China, for the final prebreeding stopover, during their 10,000-15,000 km long migrations between wintering and breeding areas. Here, they feed on small bivalves, especially 2-7 mm long Potamocorbula laevis. With an average stay of 29 days, and the need to store 80 g of fat for the onward flights to high-Arctic breeding grounds, red knots need to refuel fast. Using existing knowledge, we expected them to achieve this on the basis of (1) prey with high flesh to shell mass ratios, (2) large gizzards to crush the ingested molluscs, or (3) a combination of the two. Rejecting all three predictions, we found that red knots staging in Bohai Bay had the smallest gizzards on record (4.9 ± 0.8 g, mean ± s.e.m., N = 27), and also found that prey quality of P. laevis is much lower than predicted for the measured gizzard size (i.e. 1.3 rather than the predicted 4.5 kJ g(-1) dry shell mass, DM(shell)). The estimated handling time of P. laevis (0.2 s) is much shorter than the observed time between two prey ingestions (0.7 s), indicating that prey handling time is no constraint. Based on field observations of dropping rates and on indoor digestion trails, the shell processing rate was estimated at 3.9 mg DM(shell) s(-1), i.e. three times higher the rate previously predicted for red knots eating as fast as they can with the measured gizzard size. This is explained by the small and easily crushed P. laevis enabling high processing rates. As P. laevis also occurred in high densities, the metabolizable energy intake rate of red knots with small gizzards at 5 J s(-1) was as high as at northward staging sites elsewhere in the world. Currently, therefore, food characteristics in Bohai Bay are such that red knots can refuel fast whilst economizing on the size of their gizzard. These time-stressed migrants thus provide an elegant example of symmorphosis.
Assuntos
Migração Animal , Charadriiformes/anatomia & histologia , Charadriiformes/fisiologia , Comportamento Alimentar , Moela das Aves/anatomia & histologia , Moela das Aves/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bivalves/fisiologia , China , DietaRESUMO
Tui Na or massage therapy alleviates symptoms related to intervertebral disc degeneration (IDD). However, precise, repeatable, standardized instructions for Tuina manipulation are lacking. This study establishes IDD model rabbits induced by fibrous ring puncture, creates targeted Tuina stimulation protocols at the acupuncture points in the lumbar region, and describes in detail the operation methods and requirements of kneading, pointing, and flicking. New Zealand male white rabbits (n = 15) were selected and randomly divided into a blank group, a model group, and a Tuina group. The rabbits in the model group and the Tuina group were molded by fibrous ring puncture; the rabbits in the model group were only immobilized on the operating table without treatment. In contrast, the Tuina group used the "8N/10N, 30 cycles/min" prescription for kneading, pointing, and flicking to perform the intervention, using tactile sensory aids to monitor and regulate the intensity of the Tuina operation. Imaging diagnosis and pathological tests were used to assess the effect of Tuina in rabbits, and the results showed improved imaging features and significantly lowered pathology scores of lumbar disc degeneration in the Tuina group compared to the model group (P < 0.01). Targeted Tuina in the lumbar region may be beneficial in the alleviation of lumbar disc degeneration, but further verification is needed. By regularly performing Tuina and recording the mechanical information involved enables reproducible manipulation prescriptions and helps to observe the basic features of the underlying mechanism of Tuina for IDD.
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Terapia por Acupuntura , Degeneração do Disco Intervertebral , Animais , Masculino , Coelhos , Degeneração do Disco Intervertebral/terapia , Região Lombossacral , Massagem , Punção EspinalRESUMO
Ambipolar transport behavior in isoindigo-based conjugated polymers is observed for the first time. Fluorination on the isoindigo unit effectively lowers the LUMO level of the polymer and significantly increases the electron mobility from 10(-2) to 0.43 cm(2) V(-1) s(-1) while maintaining high hole mobility up to 1.85 cm(2) V(-1) s(-1) for FET devices fabricated in ambient. Further investigation indicates that fluorination also affects the interchain interactions of polymer backbones, thus leading to different polymer packing in thin films.
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Background Individual inborn errors of metabolism (IEMs) are rare disorders. Expanded newborn screening for IEMs by tandem mass spectrometry (TMS) is an efficient approach for early diagnosis. Here we provide the newborn screening program for the application of this approach (between July 2014 and March 2019) to the identification of newborns in Beijing at risk of developing a potentially fatal disease. Methods The amino acids and acylcarnitines in dried blood spots were analyzed by TMS. Diagnoses of newborns with elevated metabolites were confirmed by gas chromatography-mass spectrometry, biochemical studies, and genetic analysis. Results Among the healthy newborns, 16 metabolic disorder cases were confirmed, giving a total birth prevalence of 1:3666 live births. Organic acidemia (OA) was the most common (9/16 patients; 56%), and methylmalonic acidemia was the most frequently observed OA (7/9 patients; 89%). Five infants were diagnosed with methylmalonic acidemia with homocystinuria type CblC, two with isolated methylmalonic acidemia, one with propionic acidemia, and one with isovaleric acidemia. Four patients (4/16, 25%) were diagnosed with hyperphenylalaninemia. One suffered with medium-chain acyl CoA dehydrogenase deficiency, one with carnitine uptake deficiency, and one with citrin deficiency. Eleven cases underwent genetic analysis. Seventeen mutations in eight IEM-associated genes were identified in 11 confirmed cases. Symptoms were already present within 2 days after birth in 44% (7/16) cases. The infant with propionic acidemia died at 7 days after birth. The other cases received timely diagnosis and treatment, and most of them grew well. Conclusions The results illustrate challenges encountered in disease management highlighting the importance of newborn screening for inherited metabolic disorders, which is not yet nationally available in our country. Regional newborn screening programs will provide a better estimation of the incidence of IEM.
Assuntos
Aminoácidos/metabolismo , Carnitina/análogos & derivados , Erros Inatos do Metabolismo/diagnóstico , Espectrometria de Massas em Tandem/métodos , Pequim , Carnitina/metabolismo , Feminino , Humanos , Recém-Nascido , Masculino , Erros Inatos do Metabolismo/metabolismo , Triagem NeonatalRESUMO
Indigenous animals show unique gut microbiota (GM) in the Tibetan plateau. However, it is unknown whether the hypertensive indigenous people in plateau also have the distinct gut bacteria, different from those living in plains. We sequenced the V3-V4 region of the gut bacteria 16S ribosomal RNA (rRNA) gene of feces samples among hypertensive patients (HPs) and healthy individuals (HIs) from 3 distinct altitudes: Tibetans from high altitude (3600-4500 m, n = 38 and 34), Hans from middle altitude (2260 m, n = 49 and 35), and Hans from low altitude (13 m, n = 34 and 35) and then analyzed the GM composition among hypertensive and healthy subgroups using the bioinformatics analysis, respectively. The GM of high-altitude Tibetan and middle-altitude Han HPs presented greater α- and ß-diversities, lower ratio of Firmicutes/Bacteroidetes (F/B), and higher abundance of beneficial Verrucomicrobia and Akkermansia than the low-altitudes HPs did. The GM of high-altitude Tibetan and middle-altitude HIs showed greater α-diversity and lower ratio of F/B than the low-altitudes HIs did. But, ß-diversity and abundance of Verrucomicrobia and Akkermansia among different subgroups of HIs did not show any differences. Conclusively, the high-altitude Tibetan and middle-altitude Han HPs have a distinct feature of GM, which may be important in their adaptation to hypertension in the plateau environments.
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The development of reliable, eco-friendly processes for the synthesis of nanomaterials is an important aspect of nanotechnology today. One approach that shows immense potential is based on the in situ synthesis of noble metal nanocolloids using natural biological material such as silk fibroin. In the present paper, the nano-Ag/silk-fibroin colloids were prepared by in situ reducing AgNO3 with silk-fibroin at room temperature without any reducing agent. UV-Vis absorption, atomic force microscopy, fluorescence spectra and resonance scattering spectra were used to study the preparation process and characterization of the nanocomposite. It was found that the formative Ag nanoparticles were attributed to the tyrosine residues in the chains of silk-fibroin that act as reduction agent in the reduction course of AgNO3, and the Ag nanoparticles were uniformly embedded in silk-fibroin colloid, which possess good dispersity and stability and can be kept for a long period. The strength of fluorescence spectra increased after reaction of silk-fibroin with AgNO3 solution, showing that there was a strong chemical adsorption between silver nanoparticles and silk-fibroin, and a stable complex layer was formed in silver nanoparticles. Meanwhile the existence of silver nanoparticles in silk-fibroin was proved by resonance scattering spectra.
Assuntos
Nanopartículas Metálicas/análise , Nanocompostos/análise , Nanofibras/análise , Seda/química , Prata/química , Análise Espectral , Fibroínas/química , Nanopartículas Metálicas/química , Microscopia de Força Atômica , Conformação Molecular , Nanocompostos/química , Nanofibras/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Análise Espectral/métodos , Propriedades de SuperfícieRESUMO
Plateau-Rayleigh instability describes the infinite falling stream of fluid breaks into smaller droplets. With the development of nanotechnology, more and more attention is being drawn to Plateau-Rayleigh instability. This surface tension-driven instability performs well in the preparation of the nanoparticles, especially in photonics applications, such as optical micro-resonators in nano-biosensing systems. In this article, we mainly adopt the thermal fluid coupling method. The effect of temperature field on instability is studied with the aid of numerical simulation. In addition, the radius of the inner fluid column, the thickness of the outer fluid, and the temperature gradient are also studied to explore how the factors influence the Plateau-Rayleigh instability. The wavelength of the instability is characterized by droplet diameter, which is formed through the process caused by Plateau-Rayleigh instability.
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Técnicas Biossensoriais/métodos , Modelos Teóricos , Nanotecnologia/métodos , Algoritmos , Simulação por Computador , Temperatura AltaRESUMO
MicroRNA (miRNA, miR)-155 is the most promising pro-inflammatory miRNA molecule. Lipopolysaccharide (LPS) and oxidized low-density lipoprotein (oxLDL) are the most well-known foreign antigens, initiating immune responses against infection and the development of atherosclerosis (AS), respectively. To explore whether miR-155 is involved in regulating LPS- and oxLDL-initiated inflammations, we investigated the level of miR-155 in both LPS- and oxLDL-treated RAW264.7 cells, assessed whether miR-155 induce morphologic changes of the cells and how did it regulate the production of surface markers and cytokines. The results showed that the level of miR-155 was significantly increased by LPS and was modestly increased by oxLDL. Moreover, RAW264.7 cells displayed morphological transformations from macrophage-like cells into DC-like cells when miR-155 was over-expressed. Furthermore, the gain- and loss-of-function studies demonstrated that miR-155 induced the expression of the surface markers (including MHC-II, MHC-I, CD86, and CD83) and pro-inflammatory cytokines (including interleukin (IL)-12, IL-6, and IL-1b) in both LPS- and oxLDL-treated RAW264.7 cells. Additionally, miR-155 induced the expression of CD36 in oxLDL-treated RAW264.7 cells. In conclusion, up-regulated miR-155 is able to induce morphological and phenotypic changes, and the expression of pro-inflammatory cytokines in both LPS- and oxLDL-treated RAW264.7 cells. Therefore, our study suggests that miR-155 is one important regulator involved in enhancing both LPS- and oxLDL-initiated inflammations, which is critical for the progression of immune responses as well as for the development of AS.
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Transdiferenciação Celular , Células Dendríticas/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Animais , Antígenos CD36/metabolismo , Forma Celular , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Lipoproteínas LDL/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , MicroRNAs/genética , Fenótipo , Células RAW 264.7 , Fatores de Tempo , Regulação para CimaRESUMO
MicroRNA (miR)-155 is a critical player in both innate and adaptive immune responses. It can influence CD4(+) T cell lineage choice. To clarify the role of miR-155 in CD4(+) CD25(+) regulatory T (Treg)/T helper (Th)17 cell differentiation and function, as well as the mechanism involved, we performed gain-and loss-of-function analysis by transfection pre-miR-155 and anti-miR-155 into purified CD4(+) T cells. The results showed that miR-155 positively regulated both Treg and Th17 cell differentiation. It also induced the release of interleukin (IL)-17A by Th17 cells, but not the release of IL-10 and transforming growth factor (TGF)-ß1 by Treg cells. Furthermore, we found that miR-155 reacted through regulating Janus kinase/signal transducer and activator of transcription (JAK/STAT) rather than TGF-ß/mothers against decapentaplegic homolog (SMAD) signaling pathway in the process of Treg and Th17 cells differentiation. This may because suppressors of cytokine signaling (SOCS)1, the important negative regulator of JAK/STAT signaling pathway, was the direct target of miR-155 in this process, but SMAD2 and SMAD5 were not. Therefore, we demonstrated that miR-155 enhanced Treg and Th17 cells differentiation and IL-17A production by targeting SOCS1.
Assuntos
Diferenciação Celular/genética , MicroRNAs/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Células Th17/citologia , Células Th17/metabolismo , Animais , Sequência de Bases , Fatores de Transcrição Forkhead/genética , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-4/genética , Interleucina-4/metabolismo , Janus Quinases/metabolismo , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Proteína 1 Supressora da Sinalização de Citocina , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
OBJECTIVE: To investigate malignant transformation of sinonasal inverted papilloma (SIP) treated by nasal endoscopic and endoscopy-assisted surgery. METHODS: Seven cases with malignant transformation of SIP treated by nasal endoscopic and endoscopy-assisted surgery from February 2001 to December 2010 were reviewed. Followed-up time after surgery for each case was over 3 years. All cases were unilateral disease and at grade IV according to the SIP grading standards of Krouse. One case was T2, five T3, and one T4. The surgery were performed under general anaesthesia or local and strengthen anaesthesia. Postoperative radiotherapy was applied, with the doses of 60 - 70 GY. RESULTS: All cases were squamous cell carcinoma confirmed pathologically after surgery. The patients were followed up with endoscopic examination for 3 - 5 years. Of 7 cases, recurrent disease occurred in 3 years after operation, but no recurrence in other 4 cases. CONCLUSIONS: Nasal endoscopic and endoscopy-assisted surgery can be used in the treatment for the malignant transformation of SIP, with the advantages of minimally invasion, fewer complications and the well-preserved nasal functions. Application of radiotherapy after surgery could improve long-term survival efficacy of the patients.
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Neoplasias Nasais/cirurgia , Papiloma Invertido/cirurgia , Neoplasias dos Seios Paranasais/cirurgia , Idoso , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasais/patologia , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Papiloma Invertido/patologia , Neoplasias dos Seios Paranasais/patologiaRESUMO
Protandry refers the earlier arrival at breeding sites or reproductive stages of males than females. Focusing on the general phenomenon of males arriving at breeding sites earlier than females in migratory birds, we introduced six hypotheses for explaining the protandrous arrival, including rank advantage, susceptibility, constraint, mate opportunity, waiting cost, and mate choice hypothesis. We also discussed the applicability of these hypotheses to explain the protandry in migratory birds. In addition, we put forward the issues which might be important in the future research, including 1) occurrences of protandry in species of sexually homomorphism, 2) effects of global warming on protandry, and 3) effects of intrasexual competition on protandry.