RESUMEN
BACKGROUND: Despite the functions of TLRs in the parasitic infections have been extensively reported, few studies have addressed the role of TLR3 in the immune response to Schistosoma japonicum infections. The aim of this study was to investigate the properties of TLR3 in the liver of C57BL/6 mice infected by S. japonicum. METHODS: The production of TLR3+ cells in CD4+T cells (CD4+CD3+), CD8+T cells (CD8+CD3+), γδT cells (γδTCR+CD3+), NKT cells (NK1.1+CD3+), B cells (CD19+CD3-), NK (NK1.1-CD3+) cells, MDSC (CD11b+Gr1+), macrophages (CD11b+F4/80+), DCs (CD11c+CD11b+) and neutrophils (CD11b+ Ly6g+) were assessed by flow cytometry. Sections of the liver were examined by haematoxylin and eosin staining in order to measure the area of granulomas. Hematological parameters including white blood cell (WBC), red blood cell (RBC), platelet (PLT) and hemoglobin (HGB) were analyzed. The levels of ALT and AST in the serum were measured using biochemical kits. The relative titers of anti-SEA IgG and anti-SEA IgM in the serum were measured by enzyme-linked immunosorbent assay (ELISA). CD25, CD69, CD314 and CD94 molecules were detected by flow cytometry. RESULTS: Flow cytometry results showed that the expression of TLR3 increased significantly after S. japonicum infection (P < 0.05). Hepatic myeloid and lymphoid cells could express TLR3, and the percentages of TLR3-expressing MDSC, macrophages and neutrophils were increased after infection. Knocking out TLR3 ameliorated the damage and decreased infiltration of inflammatory cells in infected C57BL/6 mouse livers.,The number of WBC was significantly reduced in TLR3 KO-infected mice compared to WT-infected mice (P < 0.01), but the levels of RBC, platelet and HGB were significantly increased in KO infected mice. Moreover, the relative titers of anti-SEA IgG and anti-SEA IgM in the serum of infected KO mice were statistically decreased compared with the infected WT mice. We also compared the activation-associated molecules expression between S.japonicum-infected WT and TLR3 KO mice. CONCLUSIONS: Taken together, our data indicated that TLR3 played potential roles in the context of S. japonicum infection and it may accelerate the progression of S. japonicum-associated liver pathology.
Asunto(s)
Schistosoma japonicum , Animales , Ratones , Schistosoma japonicum/metabolismo , Receptor Toll-Like 3/metabolismo , Ratones Endogámicos C57BL , Inmunoglobulina G , Inmunoglobulina MRESUMEN
CD103 is an important marker of tissue-resident memory T cells (TRM) which play important roles in fighting against infection. However, the immunological characteristics of CD103+ T cells are not thoroughly elucidated in the liver of mouse infected with Plasmodium. Six- to eight-week-old C57BL/6 mice were infected with Plasmodium yoelii nigeriensis NSM. Mice were sacrificed on 12-16 days after infection and the livers were picked out. Sections of the livers were stained, and serum aspartate aminotransferase (AST) and alanine transaminase (ALT) levels were measured. Moreover, lymphocytes in the liver were isolated, and the expression of CD103 was determined by using qPCR. The percentage of CD103 on different immune cell populations was dynamically observed by using flow cytometry (FCM). In addition, the phenotype and cytokine production characteristics of CD103+CD8+ Tc cell were analyzed by using flow cytometry, respectively. Erythrocyte stage plasmodium infection could result in severe hepatic damage, a widespread inflammatory response and the decrease of CD103 expression on hepatic immune cells. Only CD8+ Tc and γδT cells expressed higher levels of CD103 in the uninfected state.CD103 expression in CD8+ Tc cells significantly decreased after infection. Compared to that of CD103- CD8+ Tc cells, CD103+ CD8+ Tc cells from the infected mice expressed lower level of CD69, higher level of CD62L, and secreted more IL-4, IL-10, IL-17, and secreted less IFN-γ. CD103+CD8+ Tc cells might mediate the hepatic immune response by secreting IL-4, IL-10, and IL-17 except IFN-γ in the mice infected with the erythrocytic phase plasmodium, which could be involved in the pathogenesis of severe liver damage resulted from the erythrocytic phase plasmodium yoelii nigeriensis NSM infection.
Asunto(s)
Malaria , Plasmodium yoelii , Animales , Ratones , Linfocitos T CD8-positivos/metabolismo , Interleucina-10/metabolismo , Interleucina-17 , Interleucina-4 , Hígado , Malaria/inmunología , Malaria/metabolismo , Ratones Endogámicos C57BLRESUMEN
Cellulose (C) and Antarctic krill protein (AKP) were dissolved at low temperature, and then C/AKP composite fibers were prepared by wet spinning. In this paper, the effect of coagulation bath temperature on the properties of C/AKP composite fibers were studied by FT-IR, XRD, DSC, and other tests. The results showed that, when the temperature of the coagulation bath increased from 5 to 25 °C, the intermolecular hydrogen bond content of the C/AKP composite fibers increased from 28.20% to 31.33%. When the coagulation bath temperature is 15 °C, the breaking strength of the composite fibers is 1.64cN/dtex, which is 12% higher than that of the composite fibers at room temperature. At this temperature, the crystallinity of the composite fibers is improved, the thermal stability is slightly improved, and the surface morphology is smoother. Inspiringly, when zinc sulfate is added to the coagulation bath, the formation process of the fibers is milder. Moreover, the C/AKP composite fibers have excellent antibacterial activity against Escherichia coli and Staphylococcus aureus.
Asunto(s)
Celulosa , Euphausiacea , Animales , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus , TemperaturaRESUMEN
Fe3O4@CNF anode material for Li-ion batteries (LIBs) was designed and fabricated using lyotropic cellulose acetate as the carbon nanofiber (CNF) phase and Fe(acac)3 as the Fe3O4 phase through the electrospinning approach. Because the CNFs could retard the change of Fe3O4 volume during the electrochemical cycling and improve the electrical conductivity and the introduction of Fe3O4 could offer a larger specific surface area and more mesopores to promote electrolyte penetration and Li+ diffusion, the Fe3O4@CNFs electrode showed high reversible capacities (RCs) of 773.6 and 596.5 mAh g-1 after 300 cycles and capacity residuals of 98.0 and 99.0% at high current densities 1 and 2 A g-1, respectively. This simple method to fabricate Fe3O4@CNFs composite as anode material can be widely applied to fabricate metal oxides and bio-carbon composite nanofibers for high-performance energy storage materials.
RESUMEN
We developed a facile one-pot method to synthesize multishelled hollow mesoporous SiO2 microspheres (HMSs) with controllable interior structures including one-shell, double-shell, and yolk-shell. Single reagent formaldehyde could fully control the morphology of HMSs, in that formaldehyde was crucial to the SiO2 precursor's hydrolysis rate and the template pore size.
RESUMEN
A concise and facile sol-gel method to prepare multiple magnetic SiO2/Fe xO y hollow porous spheres was developed. A series of SiO2/Fe xO y hollow porous spheres consisting of single shell, yolk-shell, double shells, and triple shells could be obtained by simply adjusting the formaldehyde amount, as Fe(acac)3 was used as the shell-forming promoter. As the formaldehyde amount increases, the morphology of the as-prepared hollow spheres changed from single-shelled, yolk-shelled, double-shelled, to triple-shelled and then turned back. The spheres possess a large specific surface area (â¼966 m2/g), uniform mesopores (â¼4.5 nm), and large pore volume (1.37 cm3/g). Moreover, the yolk-shelled spheres have been successfully used in in situ adsorbing and reducing heavy metal ions in aqueous solution; the results suggested that it was an efficient adsorbent and convenient to concentrate from water.
RESUMEN
MicroRNAs (miRNAs) modulate complex physiological and pathological processes, including the regulation of angiogenesis. Our previous study reported that bone marrow-derived mesenchymal stem cells (MSCs) are recruited into choroidal neovascularization lesions. miRNA-195 is highly expressed in MSCs, but its function remains unknown. In the present study, miR-195a-3p abundance was significantly decreased in hypoxia-treated murine MSCs; on the other hand, its overexpression reduced MSC proliferation and migration while increasing the activation of anti-angiogenic factor pigment epithelium-derived factor (PEDF). We further discovered that matrix metalloproteinase 2 (Mmp2) transcript is a target of miR-195a-3p, and that silencing Mmp2 phenocopied the reduced proliferation and migration of MSCs. The therapeutic potential of miR-195a-3p as an angiogenesis inhibitor was also demonstrated in a laser-induced choroidal neovascularization mouse model. These findings collectively indicate that miR-195a-3p is a negative modulator of angiogenesis, and could be used as an angiogenesis inhibitor. Mol. Reprod. Dev. 83: 413-423, 2016. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Inhibidores de la Angiogénesis/metabolismo , Neovascularización Coroidal/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Células Madre Mesenquimatosas/metabolismo , MicroARNs/metabolismo , Inhibidores de la Angiogénesis/genética , Animales , Células de la Médula Ósea/patología , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Femenino , Células Madre Mesenquimatosas/patología , Ratones , MicroARNs/genética , Factores de Crecimiento Nervioso/genética , Factores de Crecimiento Nervioso/metabolismo , Serpinas/genética , Serpinas/metabolismoRESUMEN
A polyelectrolyte system consisting of sodium alginate (SA) and quaternary ammonium chitosan (QAC) blended with polydopamine-coated copper sulfide particles (CuS@PDA) was chosen to investigate the function of CuS@PDA in the uniform binary blending of anionic and cationic polyelectrolytes in detail. A smart composite fiber SA/QAC/CuS@PDA was prepared via a dry-wet spinning technique. With the addition of CuS@PDA (about 4.3 % in fiber), the as-prepared SA/QAC/CuS@PDA-0.50 fibers (SQCuS@P-0.50 SCFs) showed notably enhanced intensity 359.2 MPa, excellent moisture response, and photothermal conversion performance, with the temperature increasing from 25.9 to 80.7 °C as irradiated under a 980 nm infrared lamp at distance 20 cm away for 120 s. The photothermal performance was maintained after 6 lighting on-and-off cycles. The tensile strength decreased ~23.8 % after 4 cycles, then remained fixed. The diameter increases to ~480 % in wet state but decreases to the original size in dry state for 10 cycles. When the fabric with 90 wt% SQCuS@P-0.50 SCFs was used as a water evaporator, the water evaporation rate and efficiency were 1.68 kg·m-2·h-1 and 102 % under 1 sun irradiation. This work provides a simple and ecofriendly strategy for fabricating photothermal fabrics by designing and preparing composite fibers.
RESUMEN
Although the functions of programmed death-1 (PD-1) on αß T cells have been extensively reported, a role for PD-1 in regulating γδT cell function is only beginning to emerge. Here, we investigated the phenotypic and functional characteristics of PD-1-expressing γδT cells, and the molecular mechanism was also explored in the Plasmodium yoelii nigeriensis (P. yoelii NSM)-infected mice. Flow cytometry and single-cell RNA sequencing (scRNA-seq) were performed. An inverse agonist of RORα, SR3335, was used to investigate the role of RORα in regulating PD-1+ γδT cells. The results indicated that γδT cells continuously upregulated PD-1 expression during the infection period. Higher levels of CD94, IL-10, CX3CR1, and CD107a; and lower levels of CD25, CD69, and CD127 were found in PD-1+ γδT cells from infected mice than in PD-1- γδT cells. Furthermore, GO enrichment analysis revealed that the marker genes in PD-1+ γδT cells were involved in autophagy and processes utilizing autophagic mechanisms. ScRNA-seq results showed that RORα was increased significantly in PD-1+ γδT cells. GSEA identified that RORα was mainly involved in the regulation of I-kappaB kinase/NF-κB signaling and the positive regulation of cytokine production. Consistent with this, PD-1-expressing γδT cells upregulated RORα following Plasmodium yoelii infection. Additionally, in vitro studies revealed that higher levels of p-p65 were found in PD-1+ γδT cells after treatment with a RORα selective synthetic inhibitor. Collectively, these data suggest that RORα-mediated attenuation of NF-κB signaling may be fundamental for PD-1-expressing γδT cells to modulate host immune responses in the spleen of Plasmodium yoelii nigeriensis-infected C57BL/6 mice, and it requires further investigation.
Asunto(s)
Malaria , Plasmodium yoelii , Receptor de Muerte Celular Programada 1 , Bazo , Animales , Plasmodium yoelii/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Malaria/inmunología , Malaria/parasitología , Ratones , Bazo/inmunología , Bazo/parasitología , Femenino , Transducción de Señal/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/inmunologíaRESUMEN
The neural mechanisms of novelty detection, especially in relation to behavior, are currently poorly understood. Here, we present a protocol for recording neuronal activity in macaque auditory cortex during novelty detection tasks. We describe steps for behavioral training, surgical headpost implantation, MRI-based electrode targeting, and electrophysiological recording. These steps allow direct assessment of the correlation between novelty detection behavior and neuronal activity. For complete details on the use and execution of this protocol, please refer to Gong et al.1.
RESUMEN
The neural mechanisms underlying novelty detection are not well understood, especially in relation to behavior. Here, we present single-unit responses from the primary auditory cortex (A1) from two monkeys trained to detect deviant tones amid repetitive ones. Results show that monkeys can detect deviant sounds, and there is a strong correlation between late neuronal responses (250-350 ms after deviant onset) and the monkeys' perceptual decisions. The magnitude and timing of both neuronal and behavioral responses are increased by larger frequency differences between the deviant and standard tones and by increasing the number of standard tones preceding the deviant. This suggests that A1 neurons encode novelty detection in behaving monkeys, influenced by stimulus relevance and expectations. This study provides evidence supporting aspects of predictive coding in the sensory cortex.
Asunto(s)
Corteza Auditiva , Potenciales Evocados Auditivos , Potenciales Evocados Auditivos/fisiología , Estimulación Acústica/métodos , Corteza Auditiva/fisiología , Neuronas/fisiologíaRESUMEN
Intestinal symbiotic microorganisms have a strong capacity to regulate the physiological functions of their host, and Drosophila serves as a useful model. Enterococcus faecium (E. faecium) is a member of the normal intestinal flora of animals. Lactic acid bacteria (LAB) such as E. faecium can promote the growth and development of Drosophila, but the mechanism of regulation of Drosophila is poorly understood. In this study, we found that E. faecium used a carbon source to produce probiotic acids. E. faecium is a symbiotic bacterium for Drosophila, and adult flies passed on parental flora to offspring. E. faecium promoted the growth and development of Drosophila, especially under poor nutritional conditions. E. faecium shortened the developmental process for Drosophila and accelerated the transformation from larva to pupa. Finally, E. faecium promoted the growth and development of Drosophila through TOR and insulin signalling pathways.
Asunto(s)
Enterococcus faecium , Probióticos , Animales , Drosophila , Crecimiento y DesarrolloRESUMEN
Splenomegaly is a prominent clinical manifestation of malaria and the causes remain incompletely clear. Anemia is induced in malaria and extramedullary splenic erythropoiesis is compensation for the loss of erythrocytes. However, the regulation of extramedullary splenic erythropoiesis in malaria is unknown. An inflammatory response could facilitate extramedullary splenic erythropoiesis in the settings of infection and inflammation. Here, when mice were infected with rodent parasites, Plasmodium yoelii NSM, TLR7 expression in splenocytes was increased. To explore the roles of TLR7 in splenic erythropoiesis, we infected wild-type and TLR7 -/- C57BL/6 mice with P. yoelii NSM and found that the development of splenic erythroid progenitor cells was impeded in TLR7 -/- mice. Contrarily, the treatment of the TLR7 agonist, R848, promoted extramedullary splenic erythropoiesis in wild-type infected mice, which highlights the implication of TLR7 on splenic erythropoiesis. Then, we found that TLR7 promoted the production of IFN-γ that could enhance phagocytosis of infected erythrocytes by RAW264.7. After phagocytosis of infected erythrocytes, the iron metabolism of RAW264.7 was upregulated, evidenced by higher iron content and expression of Hmox1 and Slc40a1. Additionally, the neutralization of IFN-γ impeded the extramedullary splenic erythropoiesis modestly and reduced the iron accumulation in the spleen of infected mice. In conclusion, TLR7 promoted extramedullary splenic erythropoiesis in P. yoelii NSM-infected mice. TLR7 enhanced the production of IFN-γ, and IFN-γ promoted phagocytosis of infected erythrocytes and the iron metabolism of macrophages in vitro, which may be related to the regulation of extramedullary splenic erythropoiesis by TLR7.
Asunto(s)
Malaria , Bazo , Ratones , Animales , Bazo/metabolismo , Eritropoyesis , Receptor Toll-Like 7 , Ratones Endogámicos C57BL , Interferón gamma/uso terapéutico , Macrófagos/metabolismo , Hierro/metabolismoRESUMEN
The inverted phase, in which the swollen minority block plus solvent forms the continuous microdomain, has been frequently observed in block copolymer (BCP)∕preferential good solvent solutions in our previous experimental works. In this paper, self-consistent field theory is employed to study the formation of inverted phase in A-B BCP solutions. The parameters of both the BCP and solvent are studied. The results show that the characteristics of both the BCP and the solvent are responsible for the inverted phase formation. With the value of χ(AB)N (χ(AB) is the Flory interaction parameter between A and B blocks and N is the degree of the polymerization), the preferential affinity of the solvent for the minority block, or the solvent monomer size increasing, the existence window of the inverted phases enlarges. Meanwhile, we analyze and discuss the formation of the inverted phase in terms of the enthalpy interaction and entropy contribution of the solvent and the results suggest that both of them play important roles in the formation of inverted phase and the comparative importance of the two items depends on the solvent molecular size.
RESUMEN
An in-situ compatibilized starch (St) and polyacrylonitrile (PAN) composite spinning solution was designed by preparing starch-graft-polyacrylonitrile (St-g-PAN) through graft copolymerizing acrylonitrile from soluble starch and using ammonium cerium nitrate (CAN) as initiator. As dimethyl sulfoxide (DMSO) was used as the solvent, St/St-g-PAN/PAN/DMSO spinning solution was prepared and St/St-g-PAN/PAN composite fibers were obtained by dry-wet spinning technique. The effects of air gap, coagulation bath, hot drawing and stretching, and thermal-setting process were studied in detail. Fourier transform infrared spectroscopy (FT-IR), solid state nuclear magnetic resonance (13C NMR), thermogravimetric analysis (TGA), X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM) were used to characterize the structure and morphology of the copolymer and the fibers. Single fiber strength tester and sonic orientation instrument were performed to measure the fiber mechanical properties and orientation degrees. The results showed that as the grafting ratio ~150.0% and the reacting mixture containing St ~9.8%, St-g-PAN ~81.6%, and homo-PAN ~8.6% in DMSO solution with 6.0 wt% in concentration were used, the spinning parameters such as air gap ~35 mm, coagulation bath concentration ~70%, temperature ~25 °C, and positive stretching ~48%, hot drawing and stretching 6 times at 80 °C, thermal-setting at 90 °C for 3 h under constant length mode were met, composite fibers with breaking strength 3.41 cN·dtex-1, breaking elongation 14.41%, sonic orientation factor 0.625, moisture recovery ratio 10.53% under standard condition (1 atm, 22 °C, and relative humidity 65%), and boiling water shrinkage ratio 9.60% were obtained. The as prepared composite fiber was better than common viscose fiber 2.11 cN·dtex-1 and cotton fiber ~3.24 cN·dtex-1 and expected to be used in the fields of medical gauze, bandage, protective clothing, et al. besides of common textiles. The in-situ compatibilization method can be applied in preparation of other composite polymer materials.
Asunto(s)
Dimetilsulfóxido , Almidón , Microscopía Electrónica de Rastreo , Polímeros , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/química , Agua/químicaRESUMEN
Stimulus-specific adaptation (SSA), defined as a decrease in responses to a common stimulus that only partially generalizes to other rare stimuli, is a widespread phenomenon in the brain that is believed to be related to novelty detection. Although cross-modal sensory processing is also a widespread phenomenon, the interaction between the two phenomena is not well understood. In this study, the thalamic reticular nucleus (TRN), which is regarded as a hub of the attentional system that contains multi-modal neurons, was investigated. The results showed that SSA existed in an interactive oddball stimulation, which mimics stimulation changes from one modality to another. In the bimodal integration, SSA to bimodal stimulation was stronger than to visual stimulation alone but similar to auditory stimulation alone, which indicated a limited integrative effect. Collectively, the present results provide evidence for independent cross-modal processing in bimodal TRN neurons.
Asunto(s)
Percepción Auditiva , Cuerpos Geniculados , Estimulación Acústica , Animales , Percepción Auditiva/fisiología , Ratas , Ratas Wistar , Núcleos Talámicos/fisiologíaRESUMEN
Sodium alginate (SA) blending with quaternary ammonium chitosan (QAC) polysaccharide polyelectrolyte complex (PEC) system was chosen to research the binary blending of anionic and cationic polyelectrolytes in detail and to fabricate SA/QAC composite fibers. The potential charge and the rheology of the PEC solution were characterized through Zeta Laser Particle Size Analyzer and DV-C Rotary Rheometer, the structure and properties of the composite fiber were examined by FT-IR, XRD, SEM, EDS, and YG004 single fiber strength meter. The results showed that as the mass ratio of SA to QAC increased from 0/1 to 10/1, the state of the binary solution in water changed from transparent uniform solution to turbid solution with flocculent precipitate, then back to uniform solution, accompanied by the electrical potential change. Moreover, the electrical potential also depended on salt in solution. By using this uniform PEC solution with the mass ratio of SA to QAC 10/1 and concentration 5.5 wt% in water, SA/QAC composite fibers with excellent performances of breaking strength 2.37 cN·dtex-1 and breaking elongation 14.11%, good antibacterial and hydrophobic properties were fabricated via green wet-spinning process. The FT-IR and EDS determination indicated there formed egg-box between SA and Ca2+, cross-linked network between glutaraldehyde(GA) and SA, QAC, respectively. Depending on its mechanical, natural, and antibacterial properties, the SA/QAC composite fiber has advantages in wound dressing, medical gauze, medical absorbable suture, and tissue engineering.
Asunto(s)
Alginatos/química , Antibacterianos/síntesis química , Quitosano/síntesis química , Polielectrolitos/química , Antibacterianos/química , Antibacterianos/farmacología , Vendajes , Quitosano/química , Quitosano/farmacología , Escherichia coli/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Pruebas de Sensibilidad Microbiana , Polisacáridos/química , Compuestos de Amonio Cuaternario/química , Reología , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Ingeniería de TejidosRESUMEN
A convenient and sensitive reversible-fluorescence sensing platform for accurate monitoring of high-valence metal ions is still very challenging. As a green kind of fluorescent carbon nanomaterials, carbon dots (CDs) have captured considerable attention because of the stable fluorescence property and low cost. Herein, we fabricated a type of nitrogen-functionalized carbon dots (N-CDs) from CMC as a fluorescent reversible sensing platform for detecting various high-valence metal ions. N-CDs with a mean size of 2.3 nm were obtained and possessed 22.9% quantum yields (QY). A label-free fluorescent probe for detection of high-valence metal ions (Fe3+, Cr6+, Mn7+) was established via the fluorescence quenching response. Among them, the detection limit (LOD) toward Fe3+ ions reached 0.8 µM. We have explored the quenching mechanism of N-CDs to explain the valence state-related electron-transfer fluorescence quenching between high-valence metal ions and N-CDs. Moreover, the valence state-related fluorescence quenching phenomenon of N-CDs in aqueous solution could be effectively recovered by introducing a reducing agent (Ti3+). This "turn off-on" fluorescence recovery system of N-CDs could be applied in different applications covering the selective detection of environmental high-valence metal ions and cellular imaging.
RESUMEN
The rat auditory cortex is divided anatomically into several areas, but little is known about the functional differences in information processing among these areas. Three tonotopically organized core fields, namely, the primary (A1), anterior (AAF), and ventral (VAF) auditory fields, as well as one non-tonotopically organized belt field, the dorsal belt (DB), were identified based on their response properties. Compared to neurons in A1, AAF and VAF, units in the DB exhibited little or no response to pure tones but strong responses to white noise. The few DB neurons responded to pure tones with thresholds greater than 60â¯dB SPL, which was significantly higher than the thresholds of neurons in the core regions. In response to white noise, units in DB showed significantly longer latency and lower peak response, as well as longer response duration, than those in the core regions. Responses to repeated white noise were also examined. In contrast to neurons in A1, AAF and VAF, DB neurons could not follow repeated stimulation at a 300â¯ms inter-stimulus interval (ISI) and showed a significant steeper ISI tuning curve slope when the ISI was increased from 300â¯ms to 4.8â¯s. These results indicate that the DB processes auditory information on broader spectral and longer temporal scales than the core regions, reflecting a distinct role in the hierarchical cortical pathway.
Asunto(s)
Estimulación Acústica , Corteza Auditiva , Vías Auditivas , Mapeo Encefálico , Animales , Neuronas , Ratas , VigiliaRESUMEN
To alleviate the serious gastrointestinal side reaction of indomethacin (IDM), sodium alginate/feather keratin (SA/FK) fiber with skin-core structure was prepared via wet spinning as the carrier for sustained release of IDM. Fourier translation infrared (FT-IR) spectroscopy was adopted to investigate the reaction mechanism among SA, FK and IDM, and Ultraviolet-visible (UV-Vis) spectroscopy was used to systematically evaluate the sustained release capacity of SA/FK fiber in three simulated fluids. Scanning electron microscope (SEM) was employed to observe the apparent morphology of SA/FK fiber. The results indicate that, release amount of IDM exhibits an increase trend along with time; the release amount of IDM reaches 80% after 12 h in colon fluid and small intestinal fluid, and is less than 20% in digestive fluid. Simultaneously, FK can effectively control the release of IDM, and with the increase of FK content, IDM release time of the carrier fiber extends.