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1.
ACS Appl Mater Interfaces ; 16(25): 32394-32401, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38875495

RESUMO

Adiabatic demagnetization refrigeration is known to be the only cryogenic refrigeration technology that can achieve ultralow temperatures (≪1 K) at gravity-free conditions. The key indexes to evaluate the performance of magnetic refrigerants are their magnetic entropy changes (-ΔSm) and magnetic ordering temperature (T0). Although, based on the factors affecting the -ΔSm of magnetic refrigerants, one has been able to judge if a magnetic refrigerant has a large -ΔSm, how to accurately predict their T0 remains a huge challenge due to the fact that the T0 of magnetic refrigerants is related to not only magnetic exchange but also single-ion anisotropy and magnetic dipole interaction. Here, we, taking GdCO3F (1), Gd(HCOO)F2, Gd2(SO4)3·8H2O, GdF3, Gd(HCOO)3 and Gd(OH)3 as examples, demonstrate that the T0 of magnetic refrigerants with very weak magnetic interactions and small anisotropy can be accurately predicted by integrating mean-field approximation with quantum Monte Carlo simulations, providing an effective method for predicting the T0 of ultralow-temperature magnetic refrigerants. Thus, the present work lays a solid foundation for the rational design and preparation of ultralow-temperature magnetic refrigerants in the future.

2.
Cancer Med ; 13(10): e7310, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38785213

RESUMO

BACKGROUND: To explore the effects of monitoring measurable residual disease and post-remission treatment selection on the clinical outcomes of B-cell acute lymphoblastic leukemia (B-ALL) in adults. METHODS: Between September 2010 and January 2022, adult patients with B-ALL who received combination chemotherapy, with or without allogeneic hematopoietic stem cell transplantation (allo-HSCT), were included in the retrospective study, which was approved by the Ethics Committee and the observation of Declaration of Helsinki conditions. RESULTS: One hundred and forty-three B-ALL patients achieved complete remission (CR) were included in the study, of whom 94 patients (65.7%) received allo-HSCT in first complete remission (CR1). Multivariate analysis showed that the most powerful factors affecting OS were transplantation (hazard ratio [HR] = 0.540, p = 0.037) and sustained measurable residue disease (MRD) negativity (HR = 0.508, p = 0.037). The subgroup analysis showed that the prognosis of the allo-HSCT group was better than that of the chemotherapy group, regardless of whether MRD was negative or positive after two courses of consolidation therapy. After consolidation therapy, the prognosis of patients with positive MRD remained significantly better in the allo-HSCT group than in the chemotherapy group. However, no significant difference was observed in the prognosis between the allo-HSCT and chemotherapy groups with negative MRD after consolidation therapy. CONCLUSIONS: B-ALL patients who achieve sustained MRD negativity during consolidation therapy have excellent long-term outcomes even without allo-HSCT. Allo-HSCT is associated with a significant benefit in terms of OS and DFS for patients who were with positive MRD during consolidation therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Transplante de Células-Tronco Hematopoéticas , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras , Indução de Remissão , Humanos , Masculino , Adulto , Feminino , Estudos Retrospectivos , Prognóstico , Pessoa de Meia-Idade , Adulto Jovem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Resultado do Tratamento , Transplante Homólogo
3.
Nat Prod Res ; : 1-6, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329014

RESUMO

Three new griseofulvin derivatives, griseofulvinoside A-C (1-3), were isolated from the ethyl acetate extract of the solid fermentation product of Aureobasidium pullulans. Their structures were elucidated based on extensive spectroscopic data analysis of MS, 1D and 2D NMR. The antifungal activities of new compounds were evaluated against four phytopathogenic fungi in vitro, and all test compounds demonstrated inhibitory effects. Among them, compound 2 exhibited the most potent activities against the four selected phytopathogenic fungi with inhibitory rates ranging from 40.2 to 75.8% at 0.2 mg/mL.

4.
Inorg Chem ; 62(44): 18009-18013, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37870376

RESUMO

Ratiometric luminescent thermometers with excellent performance often require the luminescent materials to possess high thermal stability and relative sensitivity (Sr). However, such luminescent materials are very rare, especially in physiological (298-323 K) and high-temperature (>373 K) regions. Here we report the synthesis and luminescent property of [Tb0.995Eu0.005(pfbz)2(phen)Cl] (3), which not only exhibits high Sr in physiological temperature but also has a Sr up to 7.47% K-1 at 440 K, the largest Sr at 440 K in known lanthanide-based coordination compound luminescent materials.

5.
Urol Oncol ; 41(3): 149.e1-149.e9, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463084

RESUMO

BACKGROUND: The association between postoperative acute kidney injury (AKI) and long-term renal function after nephrectomy has not been fully explored, with accurate prognostic models in which AKI is an independent predicting variable still being absent. METHODS: We conducted a retrospective study of 528 patients who underwent unilateral radical nephrectomy or partial nephrectomy owing to renal cell carcinoma between January 2013 and December 2016. Postoperative AKI was defined as an absolute increase in serum creatinine level by 0.3 mg/dl or ≥5 0% increase from the preoperative value within 48 hours after surgery. The endpoint was the time to the incident stage 3 or higher chronic kidney disease (defined as eGFR<60 ml/min/1.73m²), or any claim for initiation of dialysis. Cox proportional hazards regression analysis was conducted to construct the final model. Internal validation was performed using 10-fold cross-validation. The model was evaluated in discrimination by Harrell's C-index and area under curve (AUC) values, and calibration by calibration plots. RESULTS: Five hundred twenty-eight patients were finally enrolled in the study cohort, and the median follow-up period was 38 months. Among 528 admitted patients, 232 (43.9%) developed AKI, and stage 3 or higher CKD occurred in 47 (8.9%) patients during the follow-up time, with 33 in 47 patients (70.2%) having postoperative AKI. AKI was significantly correlated with poor prognosis of renal function (HR = 3.079, P < 0.001). After the adjustment of conventional predictors, AKI was still independently related to kidney function deterioration, and the correlation was influenced by the severity of AKI. Five variables were selected to establish the prognostic model, including age, surgery type, preoperative estimated glomerular filtration rate, preoperative blood urea nitrogen, and postoperative AKI. The model had good discrimination, with the Harrell's C-index of 0.92 (95% CI 0.89-0.95), and AUC values varying from 87.7 to 95.7 at different time points. CONCLUSIONS: AKI during the perioperative period is an independent predicting factor of stage 3 or higher CKD after nephrectomy.


Assuntos
Injúria Renal Aguda , Neoplasias Renais , Insuficiência Renal Crônica , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Nefrectomia , Taxa de Filtração Glomerular , Neoplasias Renais/patologia , Rim/patologia
6.
Cancers (Basel) ; 14(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36551519

RESUMO

In the past, different bacterial species have been tested for cancer therapy in preclinical and clinical studies. The success of bacterial cancer therapy is mainly dependent on the ability of the utilized bacteria to overcome the host immune defense system to colonize the tumors and to initiate tumor-specific immunity. In recent years, several groups have demonstrated that the gut microbiome plays an important role of modulation of the host immune response and has an impact on therapeutic responses in murine models and in cohorts of human cancer patients. Here we analyzed the impact of the gut microbiome on tumor colonization and tumor therapy by the Escherichia coli Nissle 1917 (EcN) strain. This EcN strain is a promising cancer therapy candidate with probiotic properties. In our study, we observed significantly better tumor colonization by EcN after antibiotic-induced temporal depletion of the gut microbiome and after two intranasal applications of the EcN derivate (EcN/pMUT-gfp Knr) in 4T1 tumor-bearing syngeneic BALB/c mice. In addition, we demonstrated significant reduction in tumor growth and extended survival of the EcN-treated mice in contrast to phosphate-buffered saline (PBS)-treated tumor-bearing control animals. Multispectral imaging of immune cells revealed that depletion of the gut microbiome led to significantly lower infiltration of cytotoxic and helper T cells (CD4 and CD8 cells) in PBS tumors of mice pretreated with antibiotics in comparison with antibiotic untreated PBS-or EcN treated mice. These findings may help in the future advancement of cancer treatment strategies using E. coli Nissle 1917.

7.
Front Oncol ; 12: 932254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353549

RESUMO

Burkitt lymphoma or leukemia (BL) is a highly aggressive non-Hodgkin lymphoma. Older age (over 60 years old) and the presence of high-risk factors (such as abdominal mass, high levels of the serum lactic dehydrogenase, Ann Arbor stage II-IV and so on) usually predict a poorer outcome. Chimeric antigen receptor T cells (CART) have achieved remarkable success in the treatment of B-cell leukemia and lymphoma. Here, for the first time, we report a 61-year-old, high-risk BL patient with autologous stem cell transplantation (ASCT) bridging therapy prior to CART as consolidation therapy. Our findings demonstrate that the combination of ASCT and CART for BL is safe and feasible.

8.
J Am Chem Soc ; 144(30): 13787-13793, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35860923

RESUMO

Magnetic refrigerants with a large magnetocaloric effect (MCE) in a wide temperature range and low magnetic ordering temperature (To) in the sub-kelvin temperature region are not only crucial for adiabatic demagnetization refrigeration but also open up a broader parameter space for the optimal design of adiabatic demagnetization refrigerators. However, such magnetic refrigerants are extremely rare because they require magnetic materials to simultaneously satisfy three conditions: low To, weak magnetic interaction, and high magnetic density. Here, we report the syntheses, heat capacities, and magnetic properties of Gd(OH)3-xFx (1: x = 1, 2: x ≈ 1.5, and 3: x = 2), demonstrating for the first time that the introduction of fluoride anions into antiferromagnetic Gd(OH)3 can effectively regulate its To. Significantly, 3 not only has a To of 0.5 K but also exhibits a large MCE in the temperature range from 0.5 to 4 K, representing the best magnetic refrigerant reported to date in the temperature range of 0.5-4 K from the viewpoint of the MCE.

9.
Hematol Oncol ; 40(4): 637-644, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35141937

RESUMO

Autologous hematopoietic stem cell transplantation (ASCT) and chimeric antigen receptor T-cell therapy (CART) are salvage therapies that are utilised for treatment of relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL). However, whether the combination therapy of ASCT and CART (ASCT-CART) can improve the survival of R/R DLBCL remains unknown. Overall, 67 R/R DLBCL patients were included, among which 21 patients underwent ASCT-CART therapy and 46 patients underwent ASCT therapy. The median number of mononuclear cells numbers that were infused in the ASCT-CART and ASCT groups was 4.71 × 108 /kg and 5.36 × 108 /kg, respectively (p = 0.469). The median number of CD34+ cell numbers that were infused in the ASCT-CART and ASCT groups was 2.41 × 106 /kg and 3.05 × 106 /kg, respectively (p = 0.663). The median number of CART cells that were infused was 2.63 × 106 /kg with a median transduction rate of 59.83%. The objective response rates to ASCT-CART and ASCT therapy were 90% and 89%, respectively (p = 1.000). However, the ASCT-CART group showed higher complete remission (CR) rates than the ASCT group (71% vs. 33%; p = 0.003). The ASCT-CART group demonstrated superior 3 year progression-free survival (PFS) (80% vs. 44%; p = 0.036) and lower 3 year relapse/progression rate (15% vs. 56%; p = 0.015) compared to the ASCT group. However, the 3 year overall survival results indicated that there were no differences between the two groups (80% vs. 69%; p = 0.545). For R/R DLBCL patients, ASCT-CART therapy is associated with higher CR rate, better PFS, and lower relapse/progression rate. These data support that ASCT-CART therapy can be used as a salvage therapy for R/R DLBCL patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfoma Difuso de Grandes Células B , Receptores de Antígenos Quiméricos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Intervalo Livre de Progressão , Receptores de Antígenos Quiméricos/uso terapêutico , Recidiva , Estudos Retrospectivos , Rituximab , Transplante de Células-Tronco , Transplante Autólogo
10.
Bioorg Chem ; 119: 105577, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34959178

RESUMO

Phallus rubrovolvatus is an important commercially cultivated mushroom species in China. However, the volva of P. rubrovolvatus usually discarded as a by-product due to the unpleasant flavor and difficulty in processing. In this study, we investigated the chemical constituents and bioactivities of the volva of P. rubrovolvatus. As a result, fifteen rare aniline derivatives, including twelve new compounds (1-11, 14) and three new natural products (12, 13, 15) were isolated from the volva. Their structures were determined using 1D and 2D NMR data and HR-ESI-MS data, while the relative and absolute configurations were confirmed by NOESY correlations and comparison between experimental and calculated ECD spectra. In addition, compounds 1-15 were tested for anti-inflammatory activity against lipopolysaccharide (LPS)-induced NO production in RAW264.7 macrophages. Compounds 4, 9 and 10 exhibited anti-inflammatory activity with IC50 values ranging from 12.5 to 15.6 µM.


Assuntos
Compostos de Anilina/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Basidiomycota/química , Óxido Nítrico/antagonistas & inibidores , Extratos Vegetais/farmacologia , Resíduos/análise , Compostos de Anilina/química , Compostos de Anilina/isolamento & purificação , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células RAW 264.7 , Relação Estrutura-Atividade
11.
Nanomaterials (Basel) ; 13(1)2022 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-36616012

RESUMO

In this work, aramid nanofibers (ANFs)/reduced graphene oxide (ANFs/RGO) film electrodes were prepared by vacuum-assisted filtration, followed by hydroiodic acid reduction. Compared with thermal reduced ANFs/RGO, these as-prepared film electrodes exhibit a combination of mechanical and electrochemical properties with a tensile strength of 184.5 MPa and a volumetric specific capacitance of 134.4 F/cm3 at a current density of 0.125 mA/cm2, respectively. In addition, the film electrodes also show a superior cycle life with 94.6% capacitance retention after 5000 cycles. This kind of free-standing film electrode may have huge potential for flexible energy-storage devices.

12.
Biomedicines ; 9(8)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34440236

RESUMO

Engineered vaccinia virus (VACV) strains are used extensively as vectors for the development of novel cancer vaccines and cancer therapeutics. In this study, we describe for the first time a high-throughput approach for both fluorescent rVACV generation and rapid viral titer measurement with the multi-well plate imaging system, IncuCyte®S3. The isolation of a single, well-defined plaque is critical for the generation of novel recombinant vaccinia virus (rVACV) strains. Unfortunately, current methods of rVACV engineering via plaque isolation are time-consuming and laborious. Here, we present a modified fluorescent viral plaque screening and selection strategy that allows one to generally obtain novel fluorescent rVACV strains in six days, with a minimum of just four days. The standard plaque assay requires chemicals for fixing and staining cells. Manual plaque counting based on visual inspection of the cell culture plates is time-consuming. Here, we developed a fluorescence-based plaque assay for quantifying the vaccinia virus that does not require a cell staining step. This approach is less toxic to researchers and is reproducible; it is thus an improvement over the traditional assay. Lastly, plaque counting by virtue of a fluorescence-based image is very convenient, as it can be performed directly on the computer.

13.
Inorg Chem ; 60(13): 9259-9262, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34128660

RESUMO

A 3D coordination polymer, [Gd(HCOO)(C2O4)]n was prepared. Its magnetocaloric effect (MCE) (32.7 J K-1 kg-1 at 2 K and 2 T) is significantly larger than that of commercial Gd3Ga5O12 (GGG) (14.6 J kg-1 K-1 at 2 K and 2 T), while its thermal conductivity (9.9 W m-1 K-1 at 3 K) is comparable to that of the commercial GGG (about 10 W m-1 K-1 at 3 K).

14.
Methods Protoc ; 4(1)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672596

RESUMO

Stable cell lines are widely used in laboratory research and pharmaceutical industry. They are mainly applied in recombinant protein and antibody productions, gene function studies, drug screens, toxicity assessments, and for cancer therapy investigation. There are two types of cell lines, polyclonal and monoclonal origin, that differ regarding their homogeneity and heterogeneity. Generating a high-quality stable cell line, which can grow continuously and carry a stable genetic modification without alteration is very important for most studies, because polyclonal cell lines of multicellular origin can be highly variable and unstable and lead to inconclusive experimental results. The most commonly used technologies of single cell originate monoclonal stable cell isolation in laboratory are fluorescence-activated cell sorting (FACS) sorting and limiting dilution cloning. Here, we describe a modified limiting dilution method of monoclonal stable cell line selection using the real-time fluorescence imaging system IncuCyte®S3.

15.
Cell ; 184(1): 257-271.e16, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33417862

RESUMO

Hardwired circuits encoding innate responses have emerged as an essential feature of the mammalian brain. Sweet and bitter evoke opposing predetermined behaviors. Sweet drives appetitive responses and consumption of energy-rich food sources, whereas bitter prevents ingestion of toxic chemicals. Here we identified and characterized the neurons in the brainstem that transmit sweet and bitter signals from the tongue to the cortex. Next we examined how the brain modulates this hardwired circuit to control taste behaviors. We dissect the basis for bitter-evoked suppression of sweet taste and show that the taste cortex and amygdala exert strong positive and negative feedback onto incoming bitter and sweet signals in the brainstem. Finally we demonstrate that blocking the feedback markedly alters responses to ethologically relevant taste stimuli. These results illustrate how hardwired circuits can be finely regulated by top-down control and reveal the neural basis of an indispensable behavioral response for all animals.


Assuntos
Tonsila do Cerebelo/fisiologia , Encéfalo/fisiologia , Mamíferos/fisiologia , Paladar/fisiologia , Animais , Tronco Encefálico/fisiologia , Calbindina 2/metabolismo , Córtex Cerebral/fisiologia , Retroalimentação Fisiológica , Camundongos Endogâmicos C57BL , Mutação/genética , Inibição Neural/fisiologia , Neurônios/fisiologia , Núcleo Solitário/fisiologia , Somatostatina/metabolismo
16.
Front Oncol ; 11: 763151, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976810

RESUMO

SAMHD1 (sterile alpha motif domain and histidine-aspartate domain-containing protein 1) is a deoxynucleoside triphosphate triphosphohydrolase regulating innate immune and modulating DNA damage signaling. It plays an important role in the development of some tumors. SAMHD1 was also reported as a barrier to cytarabine, a common chemotherapy drug for mantle cell lymphoma (MCL), and as a biomarker of grim prognosis for acute myelocytic leukemia (AML) patients. However, SAMHD1 expression and function in MCL have not been well-defined. In the present study, we evaluated SAMHD1 expression by immunohistochemistry and its gene structure by Sanger sequencing in MCL. Our results showed that SAMHD1 was positive in 36 (62.1%) patients. Importantly, SAMHD1-positive patients were associated with lower chemotherapy response rate (p = 0.023) and shorter overall survival (p = 0.039) than SAMHD1-negative cases. These results suggest that SAMHD1 is an adverse biomarker for MCL patients, which is due to the high expression of SAMHD1 and rapid cell proliferation. These findings were confirmed in an in vitro study using the siRNA technique. Silencing the SAMHD1 gene in the MCL cell line Jeko-1 significantly decreased cell proliferation and increased cell apoptosis. The MCL cell line with SAMHD1 knockdown showed lower Ki-67 proliferation index, higher caspase-3, and higher sensitivity to cytarabine. Furthermore, for the first time, four previously unreported missense mutations (S302Y, Y432C, E449G, and R451H) in exon 8 and exon 12 of the SAMHD1 gene were discovered by sequencing. The mutations had not been found to corelate with SAMHD1 protein expression detected by immunohistochemistry. The biological functions of this mutated SAMHD1 remain to be investigated.

17.
Phys Chem Chem Phys ; 22(36): 20421-20433, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32914822

RESUMO

The multidomain kinase enzyme leucine-rich-repeat kinase 2 (LRRK2), activated through a homodimerization manner, has been identified as an important pathogenic factor in Parkinson's disease (PD), the second most common neurodegenerative disease wordwide. The Trp-Asp-40 (WD40) domain, located in the C-terminal LRRK2, harbours one of the most frequent PD-related variants, G2385R. However, the detailed dynamics of WD40 during LRRK2 dimerization and the underlying mechanism through which the pathogenic mutations disrupt the formation of the WD40 dimer have remained elusive. Here, microsecond-scale molecular dynamics simulations were employed to provide a mechanistic view underlying the WD40 dimerization and unveil the structural basis by which the interface-based mutations G2385R, H2391D and R2394E compromise the corresponding process. The simulation results identified important residues, D2351, R2394, E2395, R2413, and R2443, involved in establishing the complex binding network along the dimerization interface, which was significantly weakened in the presence of interfacial mutations. A "sag-bulge" model was proposed to explain the unfavorable dimer formation in the mutant systems. In addition, mutations altered the community configuration in the wild-type system in which inter-monomeric interplay is prominent, leading to the destabilization of the WD40 dimer under mutation.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/química , Humanos , Ligação de Hidrogênio , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Simulação de Dinâmica Molecular , Mutação , Doença de Parkinson/genética , Domínios Proteicos/genética , Multimerização Proteica/genética , Eletricidade Estática
18.
Inorg Chem ; 59(17): 12404-12409, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32794735

RESUMO

A luminescent lanthanide-titanium oxo cluster of Eu2Ti4(µ2-O)2(µ3-O)4(phen)2(tbza)10·4CH3CN (1, Eu2Ti4-phen-tbza, phen = 1,10-phenanthroline, Htbza = 4-tert-butylbenzoic acid) was prepared through the reaction of phen, Htbza, Eu(Ac)3·xH2O, and Ti(OiPr)4 in acetonitrile. Its overall absolute quantum yield is 65.4% in solid state and 30.2% in CH2Cl2, and the detection limit of 1 for the nitrobenzene (NB) is 10.5 ppb. When the concentration of NB is 40 ppm, the luminescence quenching of 1 can be observed with the naked eye. Time-resolved excited-state decay measurements indicate that the static quenching process is dominated across the NB concentration of 0-9 ppm. The distinguishable shifts in 1H NMR spectra of NB together with 1 confirm the presence of π···π stacking interactions between the organic ligands in 1 and the NB, which plays a key contribution for the quenching of luminescence.

19.
Cell ; 179(2): 392-402.e15, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31543264

RESUMO

The ability to sense sour provides an important sensory signal to prevent the ingestion of unripe, spoiled, or fermented foods. Taste and somatosensory receptors in the oral cavity trigger aversive behaviors in response to acid stimuli. Here, we show that the ion channel Otopetrin-1, a proton-selective channel normally involved in the sensation of gravity in the vestibular system, is essential for sour sensing in the taste system. We demonstrate that knockout of Otop1 eliminates acid responses from sour-sensing taste receptor cells (TRCs). In addition, we show that mice engineered to express otopetrin-1 in sweet TRCs have sweet cells that also respond to sour stimuli. Next, we genetically identified the taste ganglion neurons mediating each of the five basic taste qualities and demonstrate that sour taste uses its own dedicated labeled line from TRCs in the tongue to finely tuned taste neurons in the brain to trigger aversive behaviors.


Assuntos
Encéfalo/fisiologia , Proteínas de Membrana/metabolismo , Papilas Gustativas/metabolismo , Paladar , Ácidos/farmacologia , Vias Aferentes/citologia , Vias Aferentes/metabolismo , Vias Aferentes/fisiologia , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Feminino , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Papilas Gustativas/efeitos dos fármacos , Papilas Gustativas/fisiologia , Percepção Gustatória
20.
Sci Rep ; 8(1): 753, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29335582

RESUMO

Dysregulation of voltage-gated sodium channels (VGSCs) is associated with multiple clinical disorders, including febrile seizures (FS). The contribution of different sodium channel subtypes to environmentally triggered seizures is not well understood. Here we demonstrate that somatic and axonal sodium channels primarily mediated through NaV1.2 and NaV1.6 subtypes, respectively, behave differentially at FT, and might play distinct roles in FS generation. In contrast to sodium channels on the main axonal trunk, somatic ones are more resistant to inactivation and display significantly augmented currents, faster gating rates and kinetics of recovery from inactivation at FT, features that promote neuronal excitabilities. Pharmacological inhibition of NaV1.2 by Phrixotoxin-3 (PTx3) suppressed FT-induced neuronal hyperexcitability in brain slice, while up-regulation of NaV1.2 as in NaV1.6 knockout mice showed an opposite effect. Consistently, NaV1.6 knockout mice were more susceptible to FS, exhibiting much lower temperature threshold and shorter onset latency than wildtype mice. Neuron modeling further suggests that NaV1.2 is the major subtype mediating FT-induced neuronal hyperexcitability, and predicts potential outcomes of alterations in sodium channel subtype composition. Together, these data reveal a role of native NaV1.2 on neuronal excitability at FT and its important contribution to FS pathogenesis.


Assuntos
Potenciais de Ação , Canal de Sódio Disparado por Voltagem NAV1.2/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.6/metabolismo , Neurônios/fisiologia , Convulsões Febris/fisiopatologia , Animais , Modelos Animais de Doenças , Camundongos Knockout , Canal de Sódio Disparado por Voltagem NAV1.6/deficiência , Neurônios/efeitos da radiação , Temperatura
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