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1.
Phys Rev Lett ; 132(16): 161901, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701481

RESUMEN

We present measurements of the Born cross sections for the processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} at center-of-mass energies sqrt[s] from 4.308 to 4.951 GeV. The measurements are performed with data samples corresponding to an integrated luminosity of 11.0 fb^{-1} collected with the BESIII detector operating at the Beijing Electron Positron Collider storage ring. Assuming the e^{+}e^{-}→ωχ_{c2} signals come from a single resonance, the mass and width are determined to be M=(4413.6±9.0±0.8) MeV/c^{2} and Γ=(110.5±15.0±2.9) MeV, respectively, which is consistent with the parameters of the well-established resonance ψ(4415). In addition, we also use one single resonance to describe the e^{+}e^{-}→ωχ_{c1} line shape and determine the mass and width to be M=(4544.2±18.7±1.7) MeV/c^{2} and Γ=(116.1±33.5±1.7) MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding.

2.
Phys Rev Lett ; 132(18): 181901, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38759175

RESUMEN

Based on (10087±44)×10^{6} J/ψ events collected with the BESIII detector, a partial wave analysis of the decay J/ψ→γK_{S}^{0}K_{S}^{0}η^{'} is performed. The mass and width of the X(2370) are measured to be 2395±11(stat)_{-94}^{+26}(syst) MeV/c^{2} and 188_{-17}^{+18}(stat)_{-33}^{+124}(syst) MeV, respectively. The corresponding product branching fraction is B[J/ψ→γX(2370)]×B[X(2370)→f_{0}(980)η^{'}]×B[f_{0}(980)→K_{S}^{0}K_{S}^{0}]=(1.31±0.22(stat)_{-0.84}^{+2.85}(syst))×10^{-5}. The statistical significance of the X(2370) is greater than 11.7σ and the spin parity is determined to be 0^{-+} for the first time. The measured mass and spin parity of the X(2370) are consistent with the predictions of the lightest pseudoscalar glueball.

3.
Phys Rev Lett ; 132(23): 231902, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905649

RESUMEN

Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes Λp→Λp and Λ[over ¯]p→Λ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψ→ΛΛ[over ¯] and the protons are the hydrogen nuclei in the cooling oil of the beam pipe. Clear signals are observed for the two reactions. The cross sections in -0.9≤cosθ_{Λ/Λ[over ¯]}≤0.9 are measured to be σ(Λp→Λp)=(12.2±1.6_{stat}±1.1_{syst}) and σ(Λ[over ¯]p→Λ[over ¯]p)=(17.5±2.1_{stat}±1.6_{syst}) mb at the Λ/Λ[over ¯] momentum of 1.074 GeV/c within a range of ±0.017 GeV/c, where the θ_{Λ/Λ[over ¯]} are the scattering angles of the Λ/Λ[over ¯] in the Λp/Λ[over ¯]p rest frames. Furthermore, the differential cross sections of the two reactions are also measured, where there is a slight tendency of forward scattering for Λp→Λp, and a strong forward peak for Λ[over ¯]p→Λ[over ¯]p. We present an approach to extract the total elastic cross sections by extrapolation. The study of Λ[over ¯]p→Λ[over ¯]p represents the first study of antihyperon-nucleon scattering, and these new measurements will serve as important inputs for the theoretical understanding of the (anti)hyperon-nucleon interaction.

4.
Phys Rev Lett ; 132(13): 131901, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613263

RESUMEN

We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5 fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12

5.
Phys Rev Lett ; 132(13): 131903, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613307

RESUMEN

We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} using 2.93 fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector. As the only W-annihilation-free decay among D to a_{0}(980) pseudoscalar, D^{+}→K_{S}^{0}a_{0}(980)^{+} is the ideal decay in extracting the contributions of the W-emission amplitudes involving a_{0}(980) and to study the final-state interactions. The absolute branching fraction of D^{+}→K_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}→K_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}→π^{+}η and D^{+}→π^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}→K_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.

6.
Phys Rev Lett ; 133(12): 121801, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39373421

RESUMEN

Using 7.33 fb^{-1} of e^{+}e^{-} collision data collected by the BESIII detector at center-of-mass energies in the range of sqrt[s]=4.128-4.226 GeV, we search for the rare decays D_{s}^{+}→h^{+}(h^{0})e^{+}e^{-}, where h represents a kaon or pion. By requiring the e^{+}e^{-} invariant mass to be consistent with a ϕ(1020), 0.98

7.
Phys Rev Lett ; 133(2): 021901, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39073971

RESUMEN

Using data samples collected with the BESIII detector operating at the BEPCII storage ring, the cross section of the inclusive process e^{+}e^{-}→η+X, normalized by the total cross section of e^{+}e^{-}→hadrons, is measured at eight center-of-mass energy points from 2.0000 to 3.6710 GeV. These are the first measurements with momentum dependence in this energy region. Our measurement shows a significant discrepancy compared to the existing fragmentation functions. To address this discrepancy, a new QCD analysis is performed at the next-to-next-to-leading order with hadron mass corrections and higher twist effects, which can explain both the established high-energy data and our measurements reasonably well.

8.
Phys Rev Lett ; 133(10): 101803, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39303243

RESUMEN

A measurement of time-dependent CP violation in D^{0}→π^{+}π^{-}π^{0} decays using a pp collision data sample collected by the LHCb experiment in 2012 and from 2015 to 2018, corresponding to an integrated luminosity of 7.7 fb^{-1}, is presented. The initial flavor of each D^{0} candidate is determined from the charge of the pion produced in the D^{*}(2010)^{+}→D^{0}π^{+} decay. The decay D^{0}→K^{-}π^{+}π^{0} is used as a control channel to validate the measurement procedure. The gradient of the time-dependent CP asymmetry ΔY in D^{0}→π^{+}π^{-}π^{0} decays is measured to be ΔY=(-1.3±6.3±2.4)×10^{-4}, where the first uncertainty is statistical and the second is systematic, which is compatible with CP conservation.

9.
Phys Rev Lett ; 133(10): 101902, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39303247

RESUMEN

The J/ψ, ψ(3686)→Σ^{0}Σ[over ¯]^{0} processes and subsequent decays are studied using the world's largest J/ψ and ψ(3686) data samples collected with the BESIII detector. The parity-violating decay parameters of the decays Σ^{0}→Λγ and Σ[over ¯]^{0}→Λ[over ¯]γ, α_{Σ^{0}}=-0.0017±0.0021±0.0018 and α[over ¯]_{Σ^{0}}=0.0021±0.0020±0.0022, are measured for the first time. The strong CP symmetry is tested in the decays of the Σ^{0} hyperons for the first time by measuring the asymmetry A_{CP}^{Σ}=α_{Σ^{0}}+α[over ¯]_{Σ^{0}}=(0.4±2.9±1.3)×10^{-3}. The weak CP test is performed in the subsequent decays of their daughter particles Λ and Λ[over ¯]. Also for the first time, the transverse polarizations of the Σ^{0} hyperons in J/ψ and ψ(3686) decays are observed with opposite directions, and the ratios between the S-wave and D-wave contributions of the J/ψ, ψ(3686)→Σ^{0}Σ[over ¯]^{0} decays are obtained. These results are crucial to understand the decay dynamics of the charmonium states and the production mechanism of the Σ^{0}-Σ[over ¯]^{0} pairs.

10.
Immunity ; 42(1): 55-67, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25607459

RESUMEN

Inappropriate inflammasome activation contributes to multiple human diseases, but the mechanisms by which inflammasomes are suppressed are poorly understood. The NF-κB inhibitor A20 is a ubiquitin-modifying enzyme that might be critical in preventing human inflammatory diseases. Here, we report that A20-deficient macrophages, unlike normal cells, exhibit spontaneous NLRP3 inflammasome activity to LPS alone. The kinase RIPK3, but not the adaptor MyD88, is required for this response. In normal cells, A20 constitutively associates with caspase-1 and pro-IL-1ß, and NLRP3 activation further promotes A20 recruitment to the inflammasome. Pro-IL-1ß also co-immunoprecipitates with RIPK1, RIPK3, caspase-1, and caspase-8 in a complex that is modified with K63-linked and unanchored polyubiquitin. In A20-deficient macrophages, this pro-IL-1ß-associated ubiquitination is markedly increased in a RIPK3-dependent manner. Mass spectrometric and mutational analyses reveal that K133 of pro-IL-1ß is a physiological ubiquitination site that supports processing. Our study reveals a mechanism by which A20 prevents inflammatory diseases.


Asunto(s)
Proteínas Portadoras/metabolismo , Cisteína Endopeptidasas/metabolismo , Inflamasomas/inmunología , Interleucina-1beta/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/fisiología , Animales , Línea Celular , Cisteína Endopeptidasas/genética , Análisis Mutacional de ADN , Tolerancia Inmunológica , Interleucina-1beta/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Ratones Endogámicos , Ratones Noqueados , Complejos Multiproteicos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa , Ubiquitinación/genética
11.
Zhonghua Yi Xue Za Zhi ; 104(1): 10-15, 2024 Jan 02.
Artículo en Zh | MEDLINE | ID: mdl-38178762

RESUMEN

Objective: To investigate the indications and surgical outcome of Cobb+1 to Cobb fusion strategy in Lenke 5C adolescent idiopathic scoliosis (AIS) patients with the lower lumbar apex. Methods: The clinical data of Lenke 5C AIS patients treated in Nanjing Drum Tower Hospital from August 2015 to December 2018 were retrospectively analyzed. The patients were followed-up for at least 2 years after surgery and treated with selective Cobb+1 to Cobb fusion strategy. The patients were divided into the normal lumbar apex group (apex location of the main curve was between T12 and L1) and the lower lumbar apex group (apex location of the main curve was below the disc of L1/L2). The occurrence of proximal decompensation in the two groups was compared. In addition, according to whether the patients had proximal decompensation at the last follow-up, the patients in the lower lumbar apex group were further divided into proximal decompensation group and non-decompensation group. The radiographic parameters and Scoliosis Research Society-22 (SRS-22) scores of the two groups were compared. Results: A total of 52 patients (19 cases in the normal lumbar apex group and 33 cases in the lower lumbar apex group), aged (15.3±1.6) years, were followed up for 2-5 (3.2±1.2) years. Six patients (6/19) in the normal lumbar apex group and 5 cases (15.2%) in the lower lumbar apex group showed proximal decompensation during follow-up, and the incidence was significantly higher in the normal lumbar apex group (P=0.034). Within the lower lumbar apex group, the patients with proximal decompensation (n=5) showed similar Risser grade, baseline thoracic Cobb angle, and main Cobb angle as those without proximal decompensation(n=28), and the differences were all not statistically significant (all P>0.05). However, the baseline thoracic/lumbar apical vertebra translation (AVT) ratio was significantly larger in patients with proximal decompensation (0.6±0.2 vs 0.4±0.2, P=0.042), but the postoperative upper instrumented vertebra (UIV) tilt angle was similar (4.5°±2.3° vs 6.2°±3.4°, P=0.312). Conclusion: Cobb+1 to Cobb fusion strategy, selecting UIV at 1 level above upper end vertebra (UEV), could be performed in Lenke 5C patients with the lower lumbar apex location. In addition, UIV could be selected at UEV+1 in patients with small baseline thoracic curve.


Asunto(s)
Cifosis , Escoliosis , Fusión Vertebral , Humanos , Adolescente , Escoliosis/cirugía , Resultado del Tratamiento , Estudios Retrospectivos , Fusión Vertebral/efectos adversos , Vértebras Torácicas/cirugía , Vértebras Lumbares/cirugía , Estudios de Seguimiento
12.
Zhonghua Yi Xue Za Zhi ; 104(25): 2350-2358, 2024 Jul 02.
Artículo en Zh | MEDLINE | ID: mdl-38951108

RESUMEN

Objective: To investigate the role and underlying mechanisms of intercellular adhesion molecule-1 (ICAM-1) in the adhesion and migration of mesenchymal stem cells (MSCs) in patients with ankylosing spondylitis (AS). Methods: Bone marrow and ligament tissues were collected during surgery from patients with AS and thoracolumbar fractures (as controls, HC) treated from October 2021 to October 2022 at Nanjing University Medical School Affiliated Nanjing Drum Tower Hospital. MSCs were isolated and cultured from the bone marrow using the Ficoll separation method. Cell morphology was observed under high-resolution microscopy, and differences in the cytoskeletal features between AS-and HC-MSCs were analyzed through immunofluorescence staining. The expression of ICAM-1 was quantified in both groups using real-time quantitative polymerase chain reaction (RT-qPCR) and flow cytometry. Transwell migration assays and wound healing experiments were conducted to evaluate the differences in migration rates between the two groups of MSCs. Results: The interspinous ligament and bone marrow was acquired in AS (2 males and 1 female; 33, 37, 32 years old, respectively) and no-AS patients (2 males and 1 female; 35, 32, 38 years old, respectively). AS-MSCs exhibited broader cell morphology compared to HC-MSCs under bright field and fluorescence microscopy. Immunofluorescence staining of the interspinous ligament showed higher expression of ICAM-1 (68.38±3.42 vs 48.31±2.43) and CD105 (37.97±2.16 vs 23.36±2.06) in AS patients (both P<0.001). Western blot and RT-qPCR analysis revealed significantly stronger protein expression and transcription levels of ICAM-1 in AS-MSCs when compared to those in HC-MSCs (both P<0.001). Flow cytometry confirmed greater mean fluorescence intensity of ICAM-1 in AS-MSCs than in that in HC-MSCs (924.30±54.99 vs 636.47±40.03, P=0.002). Regarding cell adhesion efficiency, it showed no significant difference between AS-MSCs and HC-MSCs in the early stage of adhesion (0.5 h: 1 496±213 vs 1 205±163, P=0.133), but they were all significantly higher in AS-MSCs in the later stage (1 h: 2 894±172 vs 1 908±155, P=0.002; 2 h: 4 540±286 vs 3 334±188, P=0.004; 3 h: 5 212±281 vs 4 208±303, P=0.014). Finally, cell migration experiments demonstrated a stronger migration capability of AS-MSCs compared to HC-MSCs (5 449±172 vs 4 016±155, P<0.001), and the inhibition efficiency of A-205804 on the migration rate of AS-MSCs was stronger than that on HC-MSCs (2 145±239 vs 3 539±316, P=0.004). Conclusions: The aberrant expression of ICAM-1 markedly influences the adhesion and migration dynamics of MSCs. Elevated ICAM-1 levels in MSCs derives from patients with AS significantly enhance their migratory capabilities.


Asunto(s)
Adhesión Celular , Movimiento Celular , Molécula 1 de Adhesión Intercelular , Células Madre Mesenquimatosas , Espondilitis Anquilosante , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Espondilitis Anquilosante/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Adulto , Femenino , Masculino , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Estudios Retrospectivos , Células Cultivadas
13.
Circulation ; 146(22): 1694-1711, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36317529

RESUMEN

BACKGROUND: The sinoatrial node (SAN) functions as the pacemaker of the heart, initiating rhythmic heartbeats. Despite its importance, the SAN is one of the most poorly understood cardiac entities because of its small size and complex composition and function. The Hippo signaling pathway is a molecular signaling pathway fundamental to heart development and regeneration. Although abnormalities of the Hippo pathway are associated with cardiac arrhythmias in human patients, the role of this pathway in the SAN is unknown. METHODS: We investigated key regulators of the Hippo pathway in SAN pacemaker cells by conditionally inactivating the Hippo signaling kinases Lats1 and Lats2 using the tamoxifen-inducible, cardiac conduction system-specific Cre driver Hcn4CreERT2 with Lats1 and Lats2 conditional knockout alleles. In addition, the Hippo-signaling effectors Yap and Taz were conditionally inactivated in the SAN. To determine the function of Hippo signaling in the SAN and other cardiac conduction system components, we conducted a series of physiological and molecular experiments, including telemetry ECG recording, echocardiography, Masson Trichrome staining, calcium imaging, immunostaining, RNAscope, cleavage under targets and tagmentation sequencing using antibodies against Yap1 or H3K4me3, quantitative real-time polymerase chain reaction, and Western blotting. We also performed comprehensive bioinformatics analyses of various datasets. RESULTS: We found that Lats1/2 inactivation caused severe sinus node dysfunction. Compared with the controls, Lats1/2 conditional knockout mutants exhibited dysregulated calcium handling and increased fibrosis in the SAN, indicating that Lats1/2 function through both cell-autonomous and non-cell-autonomous mechanisms. It is notable that the Lats1/2 conditional knockout phenotype was rescued by genetic deletion of Yap and Taz in the cardiac conduction system. These rescued mice had normal sinus rhythm and reduced fibrosis of the SAN, indicating that Lats1/2 function through Yap and Taz. Cleavage Under Targets and Tagmentation sequencing data showed that Yap potentially regulates genes critical for calcium homeostasis such as Ryr2 and genes encoding paracrine factors important in intercellular communication and fibrosis induction such as Tgfb1 and Tgfb3. Consistent with this, Lats1/2 conditional knockout mutants had decreased Ryr2 expression and increased Tgfb1 and Tgfb3 expression compared with control mice. CONCLUSIONS: We reveal, for the first time to our knowledge, that the canonical Hippo-Yap pathway plays a pivotal role in maintaining SAN homeostasis.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas de Ciclo Celular , Humanos , Ratones , Animales , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Factor de Crecimiento Transformador beta3/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Nodo Sinoatrial/metabolismo , Calcio/metabolismo , Canal Liberador de Calcio Receptor de Rianodina , Proteínas Serina-Treonina Quinasas/genética , Homeostasis , Fibrosis , Proliferación Celular , Proteínas Supresoras de Tumor
14.
Phys Rev Lett ; 131(21): 211902, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38072611

RESUMEN

Using data samples with an integrated luminosity of 5.85 fb^{-1} collected at center-of-mass energies from 4.61 to 4.95 GeV with the BESIII detector operating at the BEPCII storage ring, we measure the cross section for the process e^{+}e^{-}→K^{+}K^{-}J/ψ. A new resonance with a mass of M=4708_{-15}^{+17}±21 MeV/c^{2} and a width of Γ=126_{-23}^{+27}±30 MeV is observed in the energy-dependent line shape of the e^{+}e^{-}→K^{+}K^{-}J/ψ cross section with a significance over 5σ. The K^{+}J/ψ system is also investigated to search for charged charmoniumlike states, but no significant Z_{cs}^{+} states are observed. Upper limits on the Born cross sections for e^{+}e^{-}→K^{-}Z_{cs}(3985)^{+}/K^{-}Z_{cs}(4000)^{+}+c.c. with Z_{cs}(3985)^{±}/Z_{cs}(4000)^{±}→K^{±}J/ψ are reported at 90% confidence levels. The ratio of branching fractions {[B(Z_{cs}(3985)^{+}→K^{+}J/ψ)]/B[Z_{cs}(3985)^{+}→(D[over ¯]^{0}D_{s}^{*+}+D[over ¯]^{*0}D_{s}^{+})]} is measured to be less than 0.03 at 90% confidence level.

15.
Clin Radiol ; 77(8): 600-606, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35662510

RESUMEN

AIM: To establish a spectral computed tomography (CT)-based nomogram for predicting the response to induction chemotherapy (ICT) in nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Fifty-four patients with NPC who underwent spectral CT examination before ICT were enrolled prospectively. Patients were assigned to response and non-response groups according to response evaluation. The predictive indicators were spectral CT parameters of venous phase, including iodine concentration (IC), normalised IC (NIC), slope of the spectral attenuation curve in Hounsfield units (λHU), effective atomic number (Eff-Z), and water concentration. Multivariate logistic regression was used to construct a predictive model. The receiver operating characteristic (ROC) and calibration curves were used to evaluate the robustness of model, while the bootstrap method was used for internal validation. The Hosmer-Lemeshow test was used to test the goodness of fit of the discriminant model. RESULTS: Multivariate logistic regression analysis showed that NIC, λHU, and Eff-Z were the potential predictors, and the three indicators were further used to establish a predictive model. The nomogram was evaluated to have good predictive performance, the area under the ROC curve was 0.909 (95% confidence interval [CI]: 0.799-0.970), and the model was well calibrated (χ2 = 8.149, p=0.419). CONCLUSIONS: The spectral CT nomogram has potential clinical value in predicting response to ICT in NPC and may help guide individualised treatment decisions.


Asunto(s)
Yodo , Neoplasias Nasofaríngeas , Humanos , Quimioterapia de Inducción , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/tratamiento farmacológico , Nomogramas , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodos
16.
J Dairy Sci ; 105(9): 7298-7307, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35863920

RESUMEN

A colorimetric and surface-enhanced Raman scattering (SERS) signal amplification platform based on 2-step aggregation of gold nanoparticles (AuNP) was constructed for the sensitive detection of melamine. In this study, the positively charged SYBR Green I was used for the first step of aggregation of AuNP, via charge neutralization, to obtain small-sized AuNP aggregates. The positively charged SYBR Green I decreased the negative charges of the surface of AuNP, which was beneficial to the aggregation of AuNP. In addition, the melamine could aggregate AuNP by decreasing the negative charges of the surface of AuNP and self-assemble with each other on the surface of AuNP by hydrogen bonds. Therefore, the second efficient aggregation of small-sized AuNP aggregates could be achieved with melamine at low concentration, resulting in significant signal changes of color and SERS. The sensitivity of a colorimetric (0.60 mg/L) and SERS (0.089 mg/L) platform, based on 2-step aggregation of AuNP, was 15 and 2.2 times higher than that based on 1-step aggregation of AuNP for detecting melamine.


Asunto(s)
Oro , Nanopartículas del Metal , Animales , Colorimetría/métodos , Colorimetría/veterinaria , Oro/química , Nanopartículas del Metal/química , Leche/química , Espectrometría Raman/métodos , Triazinas
17.
Chaos ; 32(12): 123101, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36587361

RESUMEN

Biological neurons can exhibit complex coexisting multiple firing patterns dependent on initial conditions. To this end, this paper presents a novel adaptive synapse-based neuron (ASN) model with sine activation function. The ASN model has time-varying equilibria with the variation of externally applied current and its equilibrium stability involves transitions between stable and unstable points through fold and Hopf bifurcations, resulting in complex distributions of attractive regions with heterogeneous multi-stability. Globally coexisting heterogeneous behaviors are studied by bifurcation diagram, phase portrait, dynamical distribution, and basin of attraction. The results show that the number of coexisting heterogeneous attractors can be up to 12, but for a simple neuron model, such a large number of coexisting heterogeneous attractors has not been reported in the relevant literature. Most interestingly, the ASN model also has riddled-like complex basins of attraction and four illustrative examples are depicted by the phase portraits with small changes of the initial conditions. Besides, the ASN model is implemented using a simple microcontroller platform, and various heterogeneous coexisting attractors are acquired experimentally to validate the numerical results.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Simulación por Computador , Sinapsis , Neuronas/fisiología
18.
J Digit Imaging ; 35(3): 524-533, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35149938

RESUMEN

Scoliosis is a condition of abnormal lateral spinal curvature affecting an estimated 2 to 3% of the US population, or seven million people. The Cobb angle is the standard measurement of spinal curvature in scoliosis but is known to have high interobserver and intraobserver variability. Thus, the objective of this study was to build and validate a system for automatic quantitative evaluation of the Cobb angle and to compare AI generated and human reports in the clinical setting. After IRB was obtained, we retrospectively collected 2150 frontal view scoliosis radiographs at a tertiary referral center (January 1, 2019, to January 1, 2021, ≥ 16 years old, no hardware). The dataset was partitioned into 1505 train (70%), 215 validation (10%), and 430 test images (20%). All thoracic and lumbar vertebral bodies were segmented with bounding boxes, generating approximately 36,550 object annotations that were used to train a Faster R-CNN Resnet-101 object detection model. A controller algorithm was written to localize vertebral centroid coordinates and derive the Cobb properties (angle and endplate) of dominant and secondary curves. AI-derived Cobb angle measurements were compared to the clinical report measurements, and the Spearman rank-order demonstrated significant correlation (0.89, p < 0.001). Mean difference between AI and clinical report angle measurements was 7.34° (95% CI: 5.90-8.78°), which is similar to published literature (up to 10°). We demonstrate the feasibility of an AI system to automate measurement of level-by-level spinal angulation with performance comparable to radiologists.


Asunto(s)
Escoliosis , Adolescente , Inteligencia Artificial , Humanos , Vértebras Lumbares/diagnóstico por imagen , Aprendizaje Automático , Reproducibilidad de los Resultados , Estudios Retrospectivos , Escoliosis/diagnóstico por imagen
19.
Zhonghua Yi Xue Za Zhi ; 102(19): 1458-1463, 2022 May 24.
Artículo en Zh | MEDLINE | ID: mdl-35599411

RESUMEN

Objective: To analyze the relationship between post-operative proximal junctional kyphosis (PJK) and C2-femoral heads center (C2-FH), pelvic fixation in adult spinal deformity (ASD) patients, so as to provide a reference for the preoperative decision-making and the postoperative intervention timely. Methods: It was a retrospective study that analyzed 34 cases of ASD patients who underwent posterior pedicle screw fixation in Nanjing Drum Tower Hospital between January 2017 and May 2017. ASD patients were divided into two groups according to fixation options: the sacroiliac fixation group and the non-sacroiliac fixation group. The spine-pelvis parameters were evaluated on full-length X ray films of spine at preoperatively, 2 weeks postoperatively and the last follow-up, and the incidence of PJK was recorded. Results: A total of 34 ASD patients (3 males and 31 females) were included in this study, with an average age of (58±6) years. The mean follow-up period was (2.9±1.0) years (2.0-4.0 years). The age, follow-up time and various spine-pelvis parameters showed no significant differences between the two groups (all P>0.05). The immediate postoperative C2-FH in the sacroiliac fixation group was significantly lower than that in the non-sacroiliac fixation group [(-69.46±30.85) mm vs (-31.62±15.31) mm, P<0.001]. The incidence of PJK was as high as 50.0% (8/16) in patients with sacroiliac fixation, but it was only 22% (4/18) in patients without sacroiliac fixation (P=0.016). At the last follow-up, the C2-FH of both groups were both higher than -20 mm (both were approximately -15 mm, P=0.976), indicating that the C2-FH was compensated in both groups. Due to the loss of the distal compensation ability, the incidence of PJK in the sacroiliac fixation group was higher than that in the non-sacroiliac fixation group. Due to the fixation of pelvis and most of lumbar spine, no significant differences were found in lumbar lordosis (LL), pelvic tilt (PT) and sacral slope (SS) at the last follow-up in both groups when compared with those after the operation (all P>0.05); while the thoracic kyphosis (TK) and cervical lordosis (CL) increased significantly (both P<0.05) to compensate C2-FH at the last follow-up. Conclusion: It's demonstrated that C2-FH< -2 cm and pelvic fixation are high risk factors of PJK in ASD patients. It is suggested that both global sagittal balance and pelvic fixation should be considered in decision-making and corrective surgery, rather than only focusing on spine-pelvic parameters.


Asunto(s)
Cifosis , Lordosis , Fusión Vertebral , Adulto , Femenino , Cabeza Femoral , Humanos , Cifosis/cirugía , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Vértebras Torácicas/cirugía
20.
J Endocrinol Invest ; 44(1): 173-181, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32406023

RESUMEN

PURPOSE: Both high-density lipoprotein cholesterol (HDL-C) and body mass index (BMI) have an impact on the prevalence of stroke. However, it is unclear whether BMI can modify the relationship between HDL-C and stroke. Therefore, we aimed to assess the effect of the BMI on the association between HDL-C and stroke in a hypertensive population without atrial fibrillation (AF). METHODS: We analyzed data of 10,925 hypertensive patients without AF from the Chinese Hypertension Registry Study. BMI was categorized as < 24 and ≥ 24 kg/m2. Multivariate logistic regression and smooth curve fitting (penalized spline method) were used to analyze the association between HDL-C and stroke in different BMI groups. Subgroup analysis and interaction tests were used to explore the effect of other variables on this relationship. RESULTS: The results showed a negative association between HDL-C and stroke in the BMI < 24 kg/m2 group, but HDL-C was not associated with stroke in the BMI ≥ 24 kg/m2 group. In the BMI < 24 kg/m2 group, each 1 mmol/L increase in HDL-C was associated with a 50% decreased risk of stroke [odds ratio (OR) 0.50, 95% confidence interval (CI) 0.38-0.66]. No significant relationship between HDL-C and stroke was observed in the BMI ≥ 24 kg/m2 group (OR 0.73, 95% CI 0.49-1.10). There was a significant interaction between BMI and HDL-C in regard to the prevalence of stroke in the hypertensive population without AF (PInteraction = 0.027). CONCLUSIONS: We found an inverse association between HDL-C and stroke only in the BMI < 24 kg/m2 group. The finding suggested that BMI could modify the association between HDL-C and stroke in hypertensive populations without AF.


Asunto(s)
Biomarcadores/metabolismo , Índice de Masa Corporal , HDL-Colesterol/metabolismo , Hipertensión/complicaciones , Accidente Cerebrovascular/patología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Prevalencia , Pronóstico , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/metabolismo
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