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1.
Nat Immunol ; 24(6): 979-990, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37188942

RESUMO

Antiviral CD8+ T cell immunity depends on the integration of various contextual cues, but how antigen-presenting cells (APCs) consolidate these signals for decoding by T cells remains unclear. Here, we describe gradual interferon-α/interferon-ß (IFNα/ß)-induced transcriptional adaptations that endow APCs with the capacity to rapidly activate the transcriptional regulators p65, IRF1 and FOS after CD4+ T cell-mediated CD40 stimulation. While these responses operate through broadly used signaling components, they induce a unique set of co-stimulatory molecules and soluble mediators that cannot be elicited by IFNα/ß or CD40 alone. These responses are critical for the acquisition of antiviral CD8+ T cell effector function, and their activity in APCs from individuals infected with severe acute respiratory syndrome coronavirus 2 correlates with milder disease. These observations uncover a sequential integration process whereby APCs rely on CD4+ T cells to select the innate circuits that guide antiviral CD8+ T cell responses.


Assuntos
Antivirais , COVID-19 , Humanos , Calibragem , Células Apresentadoras de Antígenos , Linfócitos T CD8-Positivos , Antígenos CD40 , Interferon-alfa , Linfócitos T CD4-Positivos
2.
J Neurosci ; 44(29)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886057

RESUMO

Calcineurin inhibitors, such as cyclosporine and tacrolimus (FK506), are commonly used immunosuppressants for preserving transplanted organs and tissues. However, these drugs can cause severe and persistent pain. GluA2-lacking, calcium-permeable AMPA receptors (CP-AMPARs) are implicated in various neurological disorders, including neuropathic pain. It is unclear whether and how constitutive calcineurin, a Ca2+/calmodulin protein phosphatase, controls synaptic CP-AMPARs. In this study, we found that blocking CP-AMPARs with IEM-1460 markedly reduced the amplitude of AMPAR-EPSCs in excitatory neurons expressing vesicular glutamate transporter-2 (VGluT2), but not in inhibitory neurons expressing vesicular GABA transporter, in the spinal cord of FK506-treated male and female mice. FK506 treatment also caused an inward rectification in the current-voltage relationship of AMPAR-EPSCs specifically in VGluT2 neurons. Intrathecal injection of IEM-1460 rapidly alleviated pain hypersensitivity in FK506-treated mice. Furthermore, FK506 treatment substantially increased physical interaction of α2δ-1 with GluA1 and GluA2 in the spinal cord and reduced GluA1/GluA2 heteromers in endoplasmic reticulum-enriched fractions of spinal cords. Correspondingly, inhibiting α2δ-1 with pregabalin, Cacna2d1 genetic knock-out, or disrupting α2δ-1-AMPAR interactions with an α2δ-1 C terminus peptide reversed inward rectification of AMPAR-EPSCs in spinal VGluT2 neurons caused by FK506 treatment. In addition, CK2 inhibition reversed FK506 treatment-induced pain hypersensitivity, α2δ-1 interactions with GluA1 and GluA2, and inward rectification of AMPAR-EPSCs in spinal VGluT2 neurons. Thus, the increased prevalence of synaptic CP-AMPARs in spinal excitatory neurons plays a major role in calcineurin inhibitor-induced pain hypersensitivity. Calcineurin and CK2 antagonistically regulate postsynaptic CP-AMPARs through α2δ-1-mediated GluA1/GluA2 heteromeric assembly in the spinal dorsal horn.


Assuntos
Calcineurina , Caseína Quinase II , Receptores de AMPA , Medula Espinal , Tacrolimo , Animais , Receptores de AMPA/metabolismo , Camundongos , Calcineurina/metabolismo , Masculino , Feminino , Tacrolimo/farmacologia , Medula Espinal/metabolismo , Medula Espinal/efeitos dos fármacos , Caseína Quinase II/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinapses/fisiologia , Inibidores de Calcineurina/farmacologia , Fenótipo , Canais de Cálcio
3.
J Neurosci ; 44(4)2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38124193

RESUMO

K+-Cl- cotransporter-2 (KCC2) critically controls neuronal chloride homeostasis and maintains normal synaptic inhibition by GABA and glycine. Nerve injury diminishes synaptic inhibition in the spinal cord via KCC2 impairment. However, how KCC2 regulates nociceptive input to spinal excitatory and inhibitory neurons remains elusive. Here, we show that basal GABA reversal potentials were significantly more depolarized in vesicular GABA transporter (VGAT)-expressing inhibitory neurons than those in vesicular glutamate transporter-2 (VGluT2)-expressing excitatory neurons in spinal cords of male and female mice. Strikingly, inhibiting KCC2 with VU0463271 increased currents elicited by puff NMDA and the NMDAR-mediated frequency of mEPSCs in VGluT2, but not in VGAT, dorsal horn neurons. Notably, VU0463271 had no effect on EPSCs monosynaptically evoked from the dorsal root in VGluT2 neurons. Furthermore, VU0463271 augmented α2δ-1-NMDAR interactions and their protein levels in spinal cord synaptosomes. In Cacna2d1 KO mice, VU0463271 had no effect on puff NMDA currents or the mEPSC frequency in dorsal horn neurons. Disrupting α2δ-1-NMDAR interactions with α2δ-1 C-terminus mimicking peptide diminished VU0463271-induced potentiation in the mEPSC frequency and puff NMDA currents in VGluT2 neurons. Additionally, intrathecal injection of VU0463271 reduced mechanical and thermal thresholds in wild-type mice, but not in Cacna2d1 KO mice. VU0463271-induced pain hypersensitivity in mice was abrogated by co-treatment with the NMDAR antagonist, pregabalin (an α2δ-1 inhibitory ligand), or α2δ-1 C-terminus mimicking peptide. Our findings suggest that KCC2 controls presynaptic and postsynaptic NMDAR activity specifically in excitatory dorsal horn neurons. KCC2 impairment preferentially potentiates nociceptive transmission between spinal excitatory interneurons via α2δ-1-bound NMDARs.Significance statementImpaired function of potassium-chloride cotransporter-2 (KCC2), a key regulator of neuronal inhibition, in the spinal cord plays a major role in neuropathic pain. This study unveils that KCC2 controls spinal nociceptive synaptic strength via NMDA receptors in a cell type- and synapse type-specific manner. KCC2 inhibition preferentially augments presynaptic and postsynaptic NMDA receptor activity in spinal excitatory interneurons via α2δ-1 (previously known as a calcium channel subunit). Importantly, spinal KCC2 impairment triggers pain hypersensitivity through α2δ-1-coupled NMDA receptors. These findings pinpoint the cell and molecular substrates for the reciprocal relationship between spinal synaptic inhibition and excitation in chronic neuropathic pain. Targeting both KCC2 and α2δ-1­NMDA receptor complexes could be an effective strategy in managing neuropathic pain conditions.


Assuntos
Receptores de N-Metil-D-Aspartato , Simportadores , Animais , Feminino , Masculino , Camundongos , Ácido gama-Aminobutírico/metabolismo , N-Metilaspartato/farmacologia , Peptídeos/farmacologia , Células do Corno Posterior/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Medula Espinal/metabolismo , Simportadores/genética , Simportadores/metabolismo , Sinapses/metabolismo
4.
Phys Rev Lett ; 132(13): 131002, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613275

RESUMO

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

5.
J Magn Reson Imaging ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38400842

RESUMO

BACKGROUND: The neurotoxic potential of gadolinium (Gd)-based contrast agents (GBCAs) retention in the brains of patients with type 2 diabetes mellitus (T2DM) is unclear. PURPOSE: To determine the deposition and clearance of GBCAs in T2DM rats and the mechanism by which Gd enhances nucleotide-binding oligomerization domain-3 (NLRP3) inflammasome activation. STUDY TYPE: Cross-sectional, prospective. ANIMAL MODEL: 104 T2DM male Wistar rats. FIELD STRENGTH/SEQUENCE: 9.4-T, T1-weighted fast spin echo sequence. ASSESSMENT: T2DM (male Wistar rats, n = 52) and control group (healthy, male Wistar rats, n = 52) rats received saline, gadodiamide, Gd-diethylenetriaminepentaacetic acid, and gadoterate meglumine for four consecutive days per week for 7 weeks. The distribution and clearance of Gd in the certain brain were assessed by MRI (T1 signal intensity and relaxation rate R1, on the last day of each week), inductively coupled plasma mass-spectroscopy, ultraperformance liquid chromatography mass spectrometry, and transmission electron microscopy. Behavioral tests, histopathological features, and the effects of GBCAs on neuroinflammation were also analyzed. STATISTICAL TESTS: One-way analysis of variance, bonferroni method, and unpaired t-test. A P-value <0.05 was considered statistically significant. RESULTS: The movement distance and appearance time in the open field test of the T2DM rats in the gadodiamide group were significantly shorter than in the other groups. Furthermore, the expression of NLRP3, Pro-Caspase-1, interleukin-1ß (IL-1ß), and apoptosis-associated speck-like protein containing a CARD protein in neurons was significantly higher in the gadodiamide group than in the saline group, as shown by Western blot. Gadodiamide also induced differentiation of microglia into M1 type, decreased the neuronal mitochondrial membrane potential, and significantly increased neuronal apoptosis from flow cytometry. DATA CONCLUSION: T2DM may affect both the deposition and clearance of GBCAs in the brain. Informed by the T2DM model, gadodiamide could mediate the neuroinflammatory response by NLRP3 inflammasome activation. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 1.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38668744

RESUMO

A Gram-stain-negative bacterium, designated LG-4T, was isolated from sediment of Qiantang River in Zhejiang Province, PR China. Cells were strictly aerobic, non-spore-forming, non-motile and short-rod-shaped (1.0-1.2 µm long and 0.7-0.8 µm wide). Growth occurred at 15-42 °C (optimum, 30 °C), at pH 5.0-9.0 (pH 7.0) and at 0-2.0 % (w/v) NaCl (optimum, 0.5 % NaCl). Strain LG-4T showed 95.75-96.90 % 16S rRNA gene sequence similarity to various type strains of the genera Tabrizicola, Pseudotabrizicola, Phaeovulum, Rhodobacter and Wagnerdoeblera of the family Paracoccaceae, and the most closely related strain was Tabrizicola soli ZQBWT (96.90 % similarity). The phylogenomic tree showed that strain LG-4T clustered in the family Paracoccaceae and was positioned outside of the clade composed of the genera Wagnerdoeblera and Falsigemmobacter. The average nucleotide identity and digital DNA-DNA hybridization values between strain LG-4T and the related type strains were in the range of 74.19-77.56 % and 16.70-25.80 %, respectively. The average amino acid identity (AAI) values between strain LG-4T and related type strains of the family Paracoccaceae were 60.94-69.73 %, which are below the genus boundary (70 %). The evolutionary distance (ED) values between LG-4T and the related genera of the family Paracoccaceae were 0.21-0.34, which are within the recommended standard (≥0.21-0.23) for defining a novel genus in the family Paracoccaceae. The predominant cellular fatty acids were C18 : 1 ω7c, C19 : 0 cyclo ω8c, C18 : 0 and C16 : 0, the isoprenoid quinone was Q-10, and the major polar lipids were phospholipid, phosphatidylglycerol, phosphatidylcholine, aminolipid and two unknown polar lipids. The genome size was 4.7 Mb with 68.6 mol% G+C content. On the basis of distinct phylogenetic relationships, low AAI values and high ED values, and differential phenotypic, physiological and biochemical characteristics, strain LG-4T represents a novel species of a new genus in the family Paracoccaceae, for which the name Ruixingdingia sedimenti gen. nov., sp. nov. is proposed. The type strain is LG-4T (=MCCC 1K08849T=KCTC 8136T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Sedimentos Geológicos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Rios , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , Ácidos Graxos/química , Ácidos Graxos/análise , DNA Bacteriano/genética , China , Sedimentos Geológicos/microbiologia , Rios/microbiologia , Fosfolipídeos/análise , Ubiquinona/análogos & derivados
7.
J Neurosci ; 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35501151

RESUMO

Understanding the pathogenesis of nigral dopaminergic neurodegeneration is critical for developing mechanism-based treatments for Parkinson's disease (PD). In the nigral dopaminergic neurons of postmortem human PD brains, we found that CREB, a well-recognized pro-survival transcription factor in neurons, was inactivated by dephosphorylation at Ser133. CREB dephosphorylation correlated with decreased expression of NURR1, one of its target genes crucial for dopaminergic neuron survival, confirming that CREB function was impaired in nigral dopaminergic neurons in PD. An MPTP mouse model was used to further elucidate the mechanism underlying CREB dephosphorylation. Protein phosphatase 1γ (PP1γ), which dephosphorylates CREB, was constitutively associated with histone deacetylase 1 (HDAC1). HDAC1 promotes CREB Ser133 dephosphorylation via a stable interaction with PP1γ. We found that CREB interacted with the HDAC1/PP1γ complex during dopaminergic neurodegeneration. Importantly, increased CREB/HDAC1 interaction occurred in the nigral dopaminergic neurons of PD patients as demonstrated using a proximity ligation assay. Disrupting CREB/HDAC1 interaction via either overexpression of GAL4 M1, a CREB mutant, or administration of trichostatin A, a pan-HDAC inhibitor, restored the expression levels of phospho-CREB (Ser133) and NURR1, and protected nigral dopaminergic neurons in the MPTP-treated mice brain. Collectively, our results demonstrated that HDAC1/PP1γ-mediated CREB inactivation contributed to dopaminergic neuronal degeneration. Disruption of CREB/HDAC1 interaction has the potential as a new approach for PD therapy.Significance StatementPD is the most common movement disorder attributed to the progressive loss of dopaminergic neurons in the substantia nigra. Understanding the pathogenesis of nigral dopaminergic neurodegeneration is critical for developing mechanism-based treatments for PD. We found in nigral dopaminergic neurons of postmortem human PD brains that CREB, a well-recognized pro-survival transcription factor in neurons, was inactivated by dephosphorylation at Ser133. HDAC1, constitutively associated with PP1γ, interacted with CREB to mediate its dephosphorylation during dopaminergic degeneration. Disrupting CREB/HDAC1 interaction restored CREB activity and protected nigral dopaminergic neurons in the MPTP mouse brains. This work suggests that disruption of the CREB/HDAC1 interaction to restore CREB activity may be a potential therapeutic approach in PD.

8.
Am Nat ; 201(4): 610-618, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958001

RESUMO

AbstractConventional analyses suggest that the metabolism of heterotrophs is thermally more sensitive than that of autotrophs, implying that warming leads to pronounced trophodynamic imbalances. However, these analyses inappropriately combine within- and across-taxa trends. Our new analysis separates these, revealing that 92% of the difference in the apparent thermal sensitivity between autotrophic and heterotrophic protists does indeed arise from within-taxa responses. Fitness differences among taxa adapted to different temperature regimes only partially compensate for the positive biochemical relationship between temperature and growth rate within taxa, supporting the hotter-is-partially-better hypothesis. Our work highlights the importance of separating within- and across-taxa responses when comparing temperature sensitivities between groups, which is relevant to how trophic imbalances and carbon fluxes respond to warming.


Assuntos
Temperatura Alta , Temperatura , Processos Autotróficos
9.
Phys Rev Lett ; 131(15): 151001, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897763

RESUMO

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

10.
Environ Res ; 216(Pt 1): 114421, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162464

RESUMO

Quinolinic acid (QA) is an essential nitrogen-containing aromatic heterocyclic compounds in organisms and it also acts as an important intermediate in chemical industry, which has strong neurotoxicity and cytotoxicity. The wide range of sources and applications caused the release and accumulation of QA in the environment which might poses a hazard to ecosystems and human health. However, few research on the degradation of QA by microorganisms and toxicity of QA and its metabolites were reported. Alcaligenes faecalis JQ191 could degrade QA but the genetic foundation of QA degradation has not been studied. In this study, the gene cluster quiA1A2A3A4 was identified from A. faecalis JQ191, which was responsible for the initial catabolism step of QA. The quiA1A2A3A4 gene cluster encodes a novel cytoplasmic four-component hydroxylase QuiA. The 1H nuclear magnetic resonance indicated that QuiA catalyzed QA to 6-hydroxyquinolinic acid (6HQA) and the H218O-labeling analysis confirmed that the hydroxyl group incorporating into 6HQA was derived from water. Toxicity tests showed that the QA could approximately inhibit 20%-80% growth of Chlorella ellipsoidea, and 6HQA could relieve at least 50% QA growth inhibition of Chlorella ellipsoidea, indicating that the 6-hydroxylation of QA by QuiA is a detoxification process. This research provides new insights into the metabolism of QA by microorganism and potential application in the bioremediation of toxic pyridine derivatives-contaminated environments.


Assuntos
Alcaligenes faecalis , Chlorella , Ácido Quinolínico , Alcaligenes faecalis/enzimologia , Alcaligenes faecalis/genética , Chlorella/metabolismo , Ecossistema , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Ácido Quinolínico/metabolismo
11.
Antonie Van Leeuwenhoek ; 116(7): 687-695, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37156982

RESUMO

A Gram-stain-negative, rod-shaped, polar flagellated or stalked and non-spore-forming bacterium, designated LB-2T, was isolated from activated sludge. Growth was observed at 20-30 °C (optimum 28 °C), pH 6.0-8.0 (optimum pH 7.0) and salinity of 0-0.5% (w/v; optimum 0.5%). Phylogenetic analysis based on the 16S rRNA gene indicated that strain LB-2T belongs to the genus Sphingomonas and showed the highest sequence similarity (96.7%) and less than 96.7% similarities to other type strains. The genome size of strain LB-2T was 4.10 Mb, with 66.8 mol% G + C content. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strains LB-2T and S. canadensis FWC47T were 77.8% and 21%, respectively. The predominant cellular fatty acids were summed feature 8 (C18:1ω7c and/or C18 : 1ω6c) and C16:0. The major polar lipids were aminolipid, glycolipid, sphingoglycolipid, phosphatidylcholine, phosphatidylglycerol, four unidentified lipids, glycophospholipid, phosphatidylethanolamine and diphosphatidylglycerol. The predominant respiratory quinone was Q-10 and the major polyamine was sym-homospermidine. On the basis of phenotypic, genotypic and phylogenetic evidences, strain LB-2T represents a novel species in the genus Sphingomonas, for which the name Sphingomonas caeni sp. nov. is proposed. The type strain is LB-2T (GDMCC 1.3630T = NBRC 115,102T).


Assuntos
Fosfolipídeos , Sphingomonas , Fosfolipídeos/química , Esgotos , Filogenia , RNA Ribossômico 16S/genética , Ubiquinona/química , Ácidos Graxos/química , DNA , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética
12.
Int J Technol Assess Health Care ; 39(1): e11, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36779272

RESUMO

OBJECTIVES: To report the processes used to design and implement an assessment tool to inform funding decisions for competing health innovations in a tertiary hospital. METHODS: We designed an assessment tool for health innovation proposals with three components: "value to the institution," "novelty," and "potential for adoption and scaling." The "value to the institution" component consisted of twelve weighted value attributes identified from the host institution's annual report; weights were allocated based on a survey of the hospital's leaders. The second and third components consisted of open-ended questions on "novelty" and "barriers to implementation" to support further dialogue. Purposive literature review was performed independently by two researchers for each assessment. The assessment tool was piloted during an institutional health innovation funding cycle. RESULTS: We used 17 days to evaluate ten proposals. The completed assessments were shared with an independent group of panellists, who selected five projects for funding. Proposals with the lowest scores for "value to the institution" had less perceived impact on the patient-related value attributes of "access," "patient centeredness," "health outcomes," "prevention," and "safety." Similar innovations were reported in literature in seven proposals; potential barriers to implementation were identified in six proposals. We included a worked example to illustrate the assessment process. CONCLUSIONS: We developed an assessment tool that is aligned with local institutional priorities. Our tool can augment the decision-making process when funding health innovation projects. The tool can be adapted by others facing similar challenges of trying to choose the best health innovations to fund.


Assuntos
Centros Médicos Acadêmicos , Humanos , Inquéritos e Questionários
13.
Phys Rev Lett ; 128(5): 051102, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35179919

RESUMO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

14.
Phys Rev Lett ; 129(26): 261103, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36608208

RESUMO

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9} GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(8): 1050-1054, 2022 Aug 06.
Artigo em Zh | MEDLINE | ID: mdl-35922230

RESUMO

In the current stage of prevention and control of the Omicron variant of the pandemic, makeshift hospitals played a key role in isolating and treating mild and asymptomatic patient, which helped to completely and quickly block the spread of the epidemic in the society. In order to reduce the risk of the spread of COVID-19 in makeshift hospital, prevent occupational exposure and nosocomial infections, it is necessary for all levels to actively identify risk sources, carry the risk assessment, implement comprehensive infection control risk treat, and supervise in a timely manner.


Assuntos
COVID-19 , Hospitais , Humanos , Controle de Infecções , Pandemias/prevenção & controle , Medição de Risco , SARS-CoV-2
16.
Zhonghua Gan Zang Bing Za Zhi ; 30(11): 1266-1269, 2022 Nov 20.
Artigo em Zh | MEDLINE | ID: mdl-36891709

RESUMO

The incidence rate of chronic hepatitis B remains high in China. Antiviral therapy can significantly reduce the risk of progressive liver disease and hepatocellular carcinoma in patients with chronic hepatitis B. However, all current antiviral treatments can only inhibit HBV replication and not completely eliminate the hepatitis B virus, so antiviral therapy for chronic hepatitis B is probably a long-term or even lifelong treatment. Antiviral therapy compliance is essential for achieving long-term clinical benefits and preventing nucleot(s)ide drugs resistance. Herein, we analyzed the relevant factors of antiviral therapy compliance and their impact on CHB treatment and explored feasible programs that can improve compliance with nucleot(s)ide drug treatment by conducting a literature search using PubMed and Scopus with search terms including hepatitis B, compliance, nucleot(s)ide drugs, antiviral therapy, viral suppression, and drug resistance.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Hepatite B Crônica/complicações , Antivirais/uso terapêutico , Vírus da Hepatite B , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Cooperação do Paciente
17.
Zhonghua Gan Zang Bing Za Zhi ; 30(4): 389-394, 2022 Apr 20.
Artigo em Zh | MEDLINE | ID: mdl-35545563

RESUMO

Objective: To investigate the effectiveness of nucleos(t)ide analogues in the treatment of HBeAg-positive chronic hepatitis B with normal alanine aminotransferase and high level of HBV DNA. Methods: Treatment-naïve chronic hepatitis B patients who were followed up at the Center of Infectious Diseases, West China Hospital of Sichuan University from January 2019 to January 2020 were selected as subjects. Demographic characteristics, the results of laboratory examination before treatment and one year after treatment were retrospectively collected. Patients were divided into tenofovir dipivoxil (TDF) and propofol fumurate tenofovir (TAF) treatment group according to different types of medication. The changes of serum HBV DNA level, HBeAg serological conversion and HBsAg quantitative level were analyzed and compared between the two groups. Results: A total of 38 cases were enrolled. Among them, there were 16 and 22 cases in the TDF and TAF group, respectively. There was no statistically significant difference in demographic characteristics, baseline HBV DNA levels and HBsAg quantitative levels between the two groups. Virological response was achieved in 60.5% (23/38) of patients after one year of antiviral therapy. Serum HBV DNA levels below the lower limit of detection [68.2% (15/22) vs. 50.0% (8/16), P=0.258] and higher HBeAg seroconversion rate [18.2%] (4/22) vs. 6.3% (1/16), P=0.374] was obtained in TAF than TDF group; however, there was no statistically significant differences between the two. Serum HBsAg quantitative level was significantly reduced with TDF and TAF treatment. In addition, alanine aminotransferase elevation was reduced in TAF than TDF treated group. Multivariate logistic regression analysis showed that patient age was an independent predictor of a virological response to antiviral therapy. Conclusion: HBeAg-positive CHB patients with normal alanine aminotransferase, and high HBV DNA level can obtain better curative effect after TDF and TAF treatment.


Assuntos
Hepatite B Crônica , Alanina Transaminase , Antivirais/uso terapêutico , DNA Viral , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Humanos , Estudos Retrospectivos , Tenofovir/uso terapêutico , Resultado do Tratamento
18.
Prog Urol ; 32(5): 388-399, 2022 Apr.
Artigo em Francês | MEDLINE | ID: mdl-35125316

RESUMO

INTRODUCTION: Inflammatory and sensory chronic bladder diseases have a significant impact on quality of life. These pathologies share alteration of the layer between urine and urothelium, making the use of topical agents appropriate. OBJECTIVES: Review the efficacy and tolerance of intravesical treatments for these pathologies. Give practical guidelines for the use of agents currently available in France. METHOD: A narrative review was performed in March 2021 using PubMed/MEDLINE, Google Scholar and the international guidelines. Pharmaceutical companies and pharmacies were interviewed. RESULTS: Although numerous molecules were tested over the last 5 decades, only dimethylsulfoxyde and glycosaminoglycans are available in France today. Results are promising: response rates are up to 95% and 84% respectively in bladder pain syndrome. In urinary tract infections, glycosaminoglycans could decrease annual number of cystitis by 2.56 (95% confidence interval (CI) -3.86, -1.26; P<0.001) and increase the time to first cystitis recurrence by 130 days (95% CI: 5.84 - 254.26; P=0.04). In radiation cystitis, results could be comparable to hyperbaric oxygen regarding pain and frequency of voiding (-1.31±1.3 visual analogic scale et -1.5±1.4 voiding per day, respectively, at 12 months, P<0.01). However, literature has a low level of evidence. CONCLUSION: Chronic bladder diseases have limited treatment options. Intravesical agents are a good alternative, although their cost is significant and their outcome uncertain.


Assuntos
Cistite Intersticial , Cistite , Administração Intravesical , Doença Crônica , Cistite/tratamento farmacológico , Cistite Intersticial/tratamento farmacológico , Feminino , Glicosaminoglicanos/uso terapêutico , Humanos , Masculino , Qualidade de Vida
19.
Neuroimage ; 241: 118427, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311069

RESUMO

The neural underpinnings of rumination can be characterized by its specific dynamic nature. Temporal stability is the stable and consistent representation of information by a distributed neural activity and connectivity pattern across brain regions. Although stability is a key feature of the brain's functional architecture, its profiles supporting rumination remain elusive. We characterized the stability of the whole-brain functional architecture during an induced, continuous rumination state and compared it with a well-constrained distraction state as the control condition in a group of healthy participants (N = 40). We further examined the relationship between stability in regions showing a significant effect on the rumination vs. distraction contrast and rumination traits. The variability of dynamic functional connectivities (FCs) among these regions was also explored to determine the potential coupling regions that drove the altered stability pattern during rumination. The results showed that rumination was characterized by a similar but altered stability profile compared with distraction and resting states. Comparison between rumination and distraction revealed that key regions of the default mode network (DMN), such as the medial prefrontal cortex (MPFC) and bilateral parahippocampal gyrus (PHG), which showed decreased stability while frontoparietal control network (FPCN) regions, including the inferior parietal lobule (IPL) and dorsal lateral prefrontal cortex (DLPFC), showed significantly enhanced stability in rumination compared with distraction. Additionally, stability in the MPFC and IPL was related to individual differences in rumination traits. Exploratory analysis of the variation in dynamic FCs suggested that higher stability in the IPL may be related to its less variable FCs with the PHG. Together, these findings implicated that rumination may be supported by the dissociated dynamic nature of hypostability in the DMN and hyperstability in the FPCN.


Assuntos
Rede de Modo Padrão/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Ruminação Cognitiva/fisiologia , Adolescente , Adulto , Rede de Modo Padrão/diagnóstico por imagem , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Descanso/fisiologia , Adulto Jovem
20.
Anal Chem ; 93(18): 6895-6900, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33904297

RESUMO

Sensing and imaging pH inside living cells are of paramount importance for better penetrating cellular functions and disease diagnostics. Herein, we engineered an original pH sensor by a simple one-step self-assembly of poly(ethylene glycol) (PEG)ylated phospholipid (DSPE-PEG) and a phenol red small molecule on the surface of upconversion nanoparticles (UCNPs) to form a phospholipid monolayer for sensing and imaging the change of intracellular pH. The sensor showed excellent reversibility and rapid response to the pH variations. Furthermore, this pH sensing system could measure spatial and temporal pH changes during endocytosis and interrogate the pH fluctuations inside cells under external stimuli. Our experimental results revealed that the pH sensor was able to map spatial and temporal pH fluctuations inside living cells, showing its potential application in diagnostics and pH-related study of cell biology.


Assuntos
Nanopartículas , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Fosfolipídeos , Polietilenoglicóis
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