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1.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728703

RESUMO

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

2.
World Neurosurg X ; 21: 100268, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38187507

RESUMO

Background: The brain undergoes reorganization following spinal cord injury (SCI), but little is known about how the thalamus is affected in pediatric SCIs. Purpose: To characterize microstructural alterations in the thalamus after SCI with diffusion tensor imaging (DTI) metrics. Methods: 18 pediatric participants with chronic SCI (8-20 years) were stratified using the American Spinal Injury Association Impairment Scale (AIS) into groups: A, B, and C/D. DTI of the brain used a 3 T Siemens Verio MRI using the parameters: 20 directions, number of averages = 3, b = 1000 s/mm2, voxel size = 1.8 mm × 1.8 mm, slice thickness = 5 mm, TE = 95 ms, TR = 4300 ms, 30 slices, FOV = 230 × 230 mm2, matrix = 128 × 128, acquisition time = 4:45 min. Diffusion data was processed to generate DTI metrics FA, MD, AD, and RD. Data analysis: DTI metrics were acquired by superimposing the AAL3 thalamic atlas onto participant diffusion images registered to MNI152 space. We utilized a multiple Mann-Whitney U-test to compare between AIS groups, considering values of p ≤ 0.05 as significant. Results: FA, AD, RD, and MD significantly differed in thalamic nuclei between AIS groups A vs B and B vs C/D. Significant nuclei include the right ventral anterior, left intralaminar, bilateral lateral pulvinar, and right lateral geniculate. Conclusion: Our findings suggest the presence of microstructural alterations based on SCI severity in pediatric patients. These results are encouraging and warrant further study.

3.
Phys Rev Lett ; 129(22): 221301, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493436

RESUMO

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4 kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80 MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90 MeV/c^{2} with heavy mediators and m_{χ} larger than 100 MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.


Assuntos
Eletricidade , Elétrons
4.
Phys Rev Lett ; 129(22): 221802, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493447

RESUMO

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46} cm^{2} (90% C.L.) at DM mass of 10 MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14 MeV/c^{2} for the massless dark photon and bound DM final state, respectively.


Assuntos
Núcleo Celular , Fótons
5.
AJNR Am J Neuroradiol ; 43(11): 1559-1566, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36175084

RESUMO

BACKGROUND AND PURPOSE: No report has been published on the use of DSC MR imaging, DCE MR imaging, and DWI parameters in combination to create a prognostic prediction model in glioblastoma patients. The aim of this study was to develop a machine learning-based model to find preoperative multiparametric MR imaging parameters associated with prognosis in patients with glioblastoma. Normalized CBV, volume transfer constant, and ADC of the nonenhancing T2 high-signal-intensity lesions were evaluated using K-means clustering. MATERIALS AND METHODS: A total of 142 patients with glioblastoma who underwent preoperative MR imaging and total resection were included in this retrospective study. From the normalized CBV, volume transfer constant, and ADC maps, the parametric data were sorted using the K-means clustering method. Patients were divided into training and test sets (ratio, 1:1), and the optimal number of clusters was determined using receiver operating characteristic analysis. Kaplan-Meier survival analysis and log-rank tests were performed to identify potential parametric predictors. A multivariate Cox proportional hazard model was conducted to adjust for clinical predictors. RESULTS: The nonenhancing T2 high-signal-intensity lesions were divided into 6 clusters. The cluster (class 4) with the relatively low normalized CBV and volume transfer constant value and the lowest ADC values was most associated with predicting glioblastoma prognosis. The optimal cutoff of the class 4 volume fraction of nonenhancing T2 high-signal-intensity lesions predicting 1-year progression-free survival was 9.70%, below which the cutoff was associated with longer progression-free survival. Two Kaplan-Meier curves based on the cutoff value showed a statistically significant difference (P = .037). When we adjusted for all clinical predictors, the cluster with the relatively low normalized CBV and volume transfer constant values and the lowest ADC value was an independent prognostic marker (hazard ratio, 3.04; P = .048). The multivariate Cox proportional hazard model showed a concordance index of 0.699 for progression-free survival. CONCLUSIONS: Our model showed that nonenhancing T2 high-signal-intensity lesions with the relatively low normalized CBV, low volume transfer constant values, and the lowest ADC values could serve as useful prognostic imaging markers for predicting survival outcomes in patients with glioblastoma.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/cirurgia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Prognóstico , Análise por Conglomerados , Meios de Contraste
6.
J Endocrinol Invest ; 45(3): 617-627, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34655038

RESUMO

OBJECTS: Cushing's disease (CD) is the most common cause of ACTH-dependent hypercortisolism in children age ≥ 7. The utility of bilateral inferior petrosal sinus sampling (BIPSS), an important test in adults, is less defined in children. We present a case series of children with ACTH-dependent hypercortisolemia and review the literature to assess the utility of BIPSS in the diagnosis and localization of CD. METHODS: We performed an IRB-approved chart review of patients aged ≤ 18 with ACTH-dependent hypercortisolism at MGH between 2000 and 2019 and collected clinical, laboratory, radiographic, BIPSS, surgical, and outcomes data. RESULTS: In our cohort (n = 21), BIPSS had a sensitivity of 93% and specificity of 100% for diagnosis of CD. Compared to surgery, successful BIPSS correctly predicted adenoma laterality in 69% of cases vs. 70% by MRI. Among patients with lesions ≥ 4 mm (n = 9), BIPSS correctly lateralized in 50% vs. 100% by MRI. In patients with subtle lesions (< 4 mm, n = 7), BIPSS correctly lateralized in 80% vs. 71% by MRI. In patients (n = 4) with CD and negative MRIs, BIPSS correctly lateralized in 75% cases. Surgical cure was achieved in 90% of patients and 95% of patients had long-term disease control. CONCLUSIONS: In our cohort (n = 21; n = 20 CD, n = 1 ectopic ACTH secretion), BIPSS was sensitive and specific for the diagnosis of CD. Compared to MRI, BIPSS was not additionally helpful for lateralization in patients with lesions ≥ 4 mm on MRI. BIPSS was helpful in guiding surgical exploration and achieving immediate postoperative remission among patients with subtle and negative MRI findings.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Hipofisectomia/métodos , Amostragem do Seio Petroso/métodos , Hipersecreção Hipofisária de ACTH , Neoplasias Hipofisárias , Adolescente , Índice de Massa Corporal , Feminino , Humanos , Hidrocortisona/urina , Imageamento por Ressonância Magnética/métodos , Masculino , Hipersecreção Hipofisária de ACTH/sangue , Hipersecreção Hipofisária de ACTH/diagnóstico , Hipersecreção Hipofisária de ACTH/patologia , Hipersecreção Hipofisária de ACTH/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Indução de Remissão/métodos , Reprodutibilidade dos Testes , Tempo , Resultado do Tratamento
7.
AJNR Am J Neuroradiol ; 43(1): 110-116, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34857516

RESUMO

BACKGROUND AND PURPOSE: Chronic carotid artery occlusion remains a poorly understood risk factor for subsequent stroke, and potential revascularization is dependent on understanding the anatomy and nature of the occlusion. Luminal imaging cannot assess the nature of an occlusion, so the internal structure of the occlusion must be inferred. The present study examines the signal characteristics of symptomatic and asymptomatic carotid occlusion that may point to management differentiation. MATERIALS AND METHODS: We prospectively recruited patients who were diagnosed with chronic carotid artery occlusion defined as longer than 4 weeks and confirmed by DSA. All patients underwent high-resolution MR vessel wall imaging examinations after enrollment. Baseline characteristics, vessel wall imaging features, and DSA features were collected and evaluated. The vessel wall imaging features included segment involvement, signal intensity, contrast enhancement, and vessel wall thickness. The symptomatic and asymptomatic chronic carotid artery occlusions were compared. RESULTS: A total of 44 patients with 48 lesions were included in this study from February 2020 to December 2020. Of the 48 lesions, 35 (72.9%) were symptomatic and 13 (27.1%) were asymptomatic. There was no difference in baseline and DSA features. On vessel wall imaging, C1 and C2 were the most commonly involved segments (91.7% and 68.8%, respectively). Compared with symptomatic lesions, asymptomatic lesions were more often isointense (69.2%) in the distal segment (P = .03). Both groups had diffuse wall thickening (80% and 100%). CONCLUSIONS: Signal characteristics between those with symptomatic and asymptomatic carotid artery occlusions differ in a statistically significant fashion, indicating a different structure of the occlusion.


Assuntos
Doenças das Artérias Carótidas , Acidente Vascular Cerebral , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/complicações , Artéria Carótida Interna/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/patologia
8.
Phys Rev E ; 104(1-1): 014151, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34412228

RESUMO

We develop a mean-field theory of the growth, exchange, and distribution (GED) model introduced by Liu et al. [K. K. L. Liu et al., preceding paper, Phys. Rev. E 104, 014150 (2021)10.1103/PhysRevE.104.014150] that accurately describes the phase transition in the limit that the number of agents N approaches infinity. The GED model is a generalization of the yard-sale model in which the additional wealth added by economic growth is nonuniformly distributed to the agents according to their wealth in a way determined by the parameter λ. The model is shown numerically to have a phase transition at λ=1 and be characterized by critical exponents and critical slowing down. Our mean-field treatment of the GED model correctly predicts the existence of the phase transition, a critical slowing down, and the values of the critical exponents and introduces an energy whose probability satisfies the Boltzmann distribution for λ<1, implying that the system is in thermodynamic equilibrium in the limit that N→∞. We show that the values of the critical exponents obtained by varying λ for a fixed value of N do not satisfy the usual scaling laws, but do satisfy scaling if a combination of parameters, which we refer to as the Ginzburg parameter, is much greater than one and is held constant. We discuss possible implications of our results for understanding economic systems and the subtle nature of the mean-field limit in systems with both additive and multiplicative noise.

9.
Phys Rev E ; 104(1-1): 014150, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34412229

RESUMO

The agent-based yard-sale model of wealth inequality is generalized to incorporate exponential economic growth and its distribution. The distribution of economic growth is nonuniform and is determined by the wealth of each agent and a parameter λ. Our numerical results indicate that the model has a critical point at λ=1 between a phase for λ<1 with economic mobility and exponentially growing wealth of all agents and a nonstationary phase for λ≥1 with wealth condensation and no mobility. We define the energy of the system and show that the system can be considered to be in thermodynamic equilibrium for λ<1. Our estimates of various critical exponents are consistent with a mean-field theory [see W. Klein et al., following paper, Phys. Rev. E 104, 014151 (2021)10.1103/PhysRevE.104.014151]. The exponents do not obey the usual scaling laws unless a combination of parameters that we refer to as the Ginzburg parameter is held fixed as the phase transition is approached. The model illustrates that both poorer and richer agents benefit from economic growth if its distribution does not favor the richer agents too strongly. This work and the following theoretical paper contribute to our understanding of whether the methods of equilibrium statistical mechanics can be applied to economic systems.

10.
Rev Sci Instrum ; 92(2): 023511, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648054

RESUMO

A capillary gas cell for laser wakefield acceleration was developed with the aid of three-dimensional computational fluid dynamics simulations. The gas cell was specially designed to provide upward density tapering in the longitudinal direction, which is expected to suppress the dephasing problem in laser wakefield acceleration by keeping the accelerated electrons in the acceleration phase of the wake wave. The density-tapered capillary gas cell was fabricated by sapphire plates, and its performance characteristics were tested. The capillary gas cell was filled with a few hundred millibars of hydrogen gas, and a Ti:sapphire laser pulse with a peak power of 3.8 TW and a pulse duration of 40 fs (full width at half maximum) was sent through the capillary hole, which has a length of 7 mm and a square cross section of 350 × 350 µm2. The laser-produced hydrogen plasma in the capillary hole was then diagnosed two-dimensionally by using a transverse Mach-Zehnder interferometer. The capillary gas cell was found to provide an upward plasma density tapering in the range of 1018 cm-3-1019 cm-3, which has a potential to enhance the electron beam energy in laser wakefield acceleration experiments.

11.
AJNR Am J Neuroradiol ; 42(5): 853-860, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33632732

RESUMO

BACKGROUND AND PURPOSE: O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status in primary and recurrent glioblastoma may change during treatment. The purpose of this study was to correlate MGMT promoter methylation status changes with DWI and DSC PWI features in patients with recurrent glioblastoma after standard treatment. MATERIALS AND METHODS: Between January 2008 and November 2016, forty patients with histologically confirmed recurrent glioblastoma were enrolled. Patients were divided into 3 groups according to the MGMT promoter methylation status for the initial and recurrent tumors: 2 groups whose MGMT promoter methylation status remained, group methylated (n = 13) or group unmethylated (n = 18), and 1 group whose MGMT promoter methylation status changed from methylated to unmethylated (n = 9). Normalized ADC and normalized relative CBV values were obtained from both the enhancing and nonenhancing regions, from which histogram parameters were calculated. The ANOVA and the Kruskal-Wallis test followed by post hoc tests were performed to compare histogram parameters among the 3 groups. The t test and Mann-Whitney U test were used to compare parameters between group methylated and group methylated to unmethylated. Receiver operating characteristic curve analysis was used to measure the predictive performance of the normalized relative CBV values between the 2 groups. RESULTS: Group methylated to unmethylated showed significantly higher means and 90th and 95th percentiles of the cumulative normalized relative CBV values of the nonenhancing region of the initial tumor than group methylated and group unmethylated (all P < .05). The mean normalized relative CBV value of the nonenhancing region of the initial tumor was the best predictor of methylation status change (P < .001), with a sensitivity of 77.78% and specificity of 92.31% at a cutoff value of 2.594. CONCLUSIONS: MGMT promoter methylation status might change in recurrent glioblastoma after standard treatment. The normalized relative CBV values of the nonenhancing region at the first preoperative MR imaging were higher in the MGMT promoter methylation change group from methylation to unmethylation in recurrent glioblastoma.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Imagem de Difusão por Ressonância Magnética/métodos , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Correlação de Dados , Metilação de DNA , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Imagem Molecular , Recidiva Local de Neoplasia , Regiões Promotoras Genéticas , Estudos Retrospectivos
12.
Int J Oral Maxillofac Surg ; 50(6): 808-814, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33051118

RESUMO

The aim of this study was to evaluate the clinical and radiographic outcomes of a lateral window approach for removal of benign minor sinus pathologies combined with transcrestal sinus floor elevation. From 2014 to 2018, all patients who received sinus pathology removal via a lateral window approach combined with transcrestal sinus floor elevation were screened. The serous exudate or minor sinus pathology was drained or removed via lateral window approach. Subsequently, transcrestal sinus floor elevation without grafting and simultaneous implant placement were performed. Panoramic radiographs and cone-beam computed tomography were taken preoperatively, immediately after surgery, and after prosthesis delivery. Twelve patients were included in this study. The decrease in Schneiderian membrane thickness was statistically significant (P<0.001). Endo-sinus bone formation was observed on the buccal (1.35±2.31mm) and palatal (1.61±2.65mm) sites of the implant. The implant survival rate was 100%. All implants survived for an average of 21.83±11.11 months. Within the limitations of this study, we suggest that the lateral window approach for minor sinus pathology removal combined with transcrestal sinus floor elevation has several advantages including endo-sinus bone gain without bone graft, minimal patient discomfort, reduced postoperative complications and shorter treatment period.


Assuntos
Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Implantação Dentária Endóssea , Humanos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Estudos Retrospectivos
13.
Hum Exp Toxicol ; 40(4): 673-684, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33021112

RESUMO

Overdose acetaminophen (APAP) can result in severe liver injury, which is responsible for nearly half of drug-induced liver injury in western countries. Previous studies have found that there existed massive hepatocellular necrosis and severe inflammatory response in APAP-induced liver injury. However, the mechanistic linkage between necroptosis and NLRP3 inflammasome pathway in APAP-induced hepatotoxicity remains poorly understood. In order to investigate the relationship between inflammation and hepatocytes death in APAP hepatotoxicity, a time-course model for APAP hepatotoxicity in C57/BL6 mice was established by intraperitoneal (i.p) injection of 300 mg/kg APAP in this study. The activity of serum enzymes and pathological changes of APAP-treated mice were evaluated, and the critical molecules in necroptosis and NF-κB-NLRP3 inflammasome signaling pathway were determined by immunoblot and immunofluorescence analysis. The results demonstrated that APAP overdose resulted in a severe liver injury. Furthermore, the expression of critical molecules in NLRP3 inflammasome and necroptosis pathways peaked at 12-24 h, and then was decreased gradually, which is consistent with the pattern of pathological injury induced by APAP. Our further investigation found that the level of IL-1ß in mouse liver was closely correlated with the level of phosphorylated MLKL following exposure to APAP. Furthermore, inhibition of necroptosis with necrostatin-1 significantly suppressed the activation of NLRP3 inflammasome signaling. Taken together, our results highlighted that the cross-talk between necroptosis and NLRP3 inflammasome played a critical role for promoting APAP-induced liver injury. Inhibition of the interaction of inflammation and necroptosis by pharmaceutical methods may represent a promising therapeutic strategy for APAP-induced liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Necroptose/efeitos dos fármacos , Acetaminofen , Analgésicos não Narcóticos , Animais , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Interleucina-1beta/metabolismo , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
14.
J Appl Microbiol ; 131(1): 93-104, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33211361

RESUMO

AIM: The aim of this study was to assess antibacterial activity of a novel Bacillus velezensis strain NST6, and further identify its active compound against pathogenic Staphylococcus strains for clinical therapeutic applications. METHODS AND RESULTS: In this study, a novel B. velezensis strain NST6 harbouring strong antimicrobial activity against human pathogenic bacteria was isolated from a soil sample. The solvent extract of the strain exhibited strong antibacterial activity against Gram-positive and Gram-negative bacteria in disc diffusion assay and measurement of minimal inhibitory concentration and bactericidal concentration, of which it showed notable efficacy to Staphylococcus species including Staphylococcus epidermidis, Staphylococcus aureus and methicillin-resistant S. aureus. Strong antibacterial effect against pathogenic S. aureus and low toxicity of the bacterial extract were further validated in Caenorhabditis elegans model. Moreover, by antibacterial activity-guided fractionation using RP-HPLC and LC-MS, we defined C15 -bacillomycin D as the anti-staphylococcal compound produced by the strain. CONCLUSION: The primary anti-staphylococcal compound from B. velezensis NST6 was identified as a cyclic lipopeptide, C15 -bacillomycin D, which proved its potential to treat Staphylococcus strains in vitro and in vivo experiments with insignificant level of toxicity. SIGNIFICANCE AND IMPACT OF THE STUDY: We provide an alternative treatment option to Staphylococcus infections by investigating the specific anti-staphylococcal activity of C15 -bacillomycin D produced by a B. velezensis strain.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bacillus/metabolismo , Lipopeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Staphylococcus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Bacillus/isolamento & purificação , Humanos , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Infecções Estafilocócicas/microbiologia
15.
Zhonghua Shao Shang Za Zhi ; 36(10): 971-974, 2020 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-33105952

RESUMO

To date, skin substitute that can provide permanent wound closure is still autologous tissue-engineered skin using autologous skin cells as seed cells. The development of cultured epithelial autograft has experienced a long and tortuous process. Autologous tissue-engineered composite skin is closer to autologous split-thickness skin graft in terms of structure, function, and efficacy, which has become a research focus in recent years. Based on the actual status of research on tissue-engineered skin application, this paper reviewed the main research progresses and existing problems, and the prospect of research and development and clinical application of autologous tissue-engineered skin as permanent graft in order to provide a reference for the improvement and application of autologous tissue-engineered skin.


Assuntos
Transplante de Pele , Pele Artificial , Humanos , Engenharia Tecidual , Transplante Autólogo
16.
Eur Rev Med Pharmacol Sci ; 24(17): 8630, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32964948

RESUMO

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Circular RNA circ_0017247 promotes melanoma migration and invasion via targeting miR-145, by Z. Chen, K. Kang, S. Chen, S. Wang, J. Zhang, X.-Y. Zhang, Z. Chen, published in Eur Rev Med Pharmacol Sci 2020; 24 (4): 1932-1938-DOI: 10.26355/eurrev_202002_20371-PMID: 32141562" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20371.

17.
Comput Biol Med ; 124: 103959, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32905923

RESUMO

Radiomics is a newly emerging field that involves the extraction of massive quantitative features from biomedical images by using data-characterization algorithms. Distinctive imaging features identified from biomedical images can be used for prognosis and therapeutic response prediction, and they can provide a noninvasive approach for personalized therapy. So far, many of the published radiomics studies utilize existing out of the box algorithms to identify the prognostic markers from biomedical images that are not specific to radiomics data. To better utilize biomedical images, we propose a novel machine learning approach, stability selection supervised principal component analysis (SSSuperPCA) that identifies stable features from radiomics big data coupled with dimension reduction for right-censored survival outcomes. The proposed approach allows us to identify a set of stable features that are highly associated with the survival outcomes in a simple yet meaningful manner, while controlling the per-family error rate. We evaluate the performance of SSSuperPCA using simulations and real data sets for non-small cell lung cancer and head and neck cancer, and compare it with other machine learning algorithms. The results demonstrate that our method has a competitive edge over other existing methods in identifying the prognostic markers from biomedical imaging data for the prediction of right-censored survival outcomes.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Análise de Componente Principal , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Aprendizado de Máquina
19.
Aust Vet J ; 98(9): 455-461, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32643275

RESUMO

A 15-month-old, male neutered Staffordshire Bull Terrier cross was presented to its referring veterinarian collapsed and agonal. He was immediately intubated, manually ventilated, and treatment commenced for presumptive snake envenomation with two vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial). The dog was transferred to a referral hospital intubated. Additional diagnostics performed following arrival at the referral hospital included a urine snake venom detection kit test, which was positive for brown snake immunotype. Three additional vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial) were administered until the dog was extubated and able to stand. Venom-induced consumptive coagulopathy (VICC) was diagnosed based on prolonged clotting times and scleral haemorrhage. Paroxysms of right ventricular outflow tract (RVOT) origin ventricular arrhythmias were treated with lignocaine and sotalol. Four days after presentation, a new-grade IV/VI systolic heart murmur was auscultated, prompting an echocardiogram. An anechoic and compartmentalised mass measuring 43 mm × 19 mm was visualized within the right ventricular wall at the RVOT, immediately adjacent to the pulmonic valve. The mass was causing a RVOT obstruction. Its appearance was suggestive of an intramyocardial haematoma, most likely secondary to VICC. The dog remained cardiovascularly stable, and treatment consisted of supportive care. Recheck echocardiograms at 2 and 7 weeks after discharge revealed progressive improvement of the intramyocardial mass and resolution of the associated heart murmur. Although intramyocardial haematomas are rare, it should be considered as a differential in dogs that develop a newly diagnosed heart murmur and/or cardiac arrhythmia following brown snake envenomation.


Assuntos
Doenças do Cão , Mordeduras de Serpentes/veterinária , Obstrução do Fluxo Ventricular Externo/veterinária , Animais , Antivenenos , Cães , Venenos Elapídicos , Elapidae , Hematoma/veterinária , Masculino
20.
Genet Epidemiol ; 44(8): 798-810, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32700329

RESUMO

Many expression quantitative trait loci (eQTL) studies have been conducted to investigate the biological effects of variants in gene regulation. However, these eQTL studies may suffer from low or moderate statistical power and overly conservative false-discovery rate. In practice, most algorithms for eQTL identification do not model the joint effects of multiple genetic variants with weak or moderate influence. Here we present a novel machine-learning algorithm, lasso least-squares kernel machine (LSKM-LASSO) that model the association between multiple genetic variants and phenotypic traits simultaneously with the existence of nongenetic and genetic confounding. With a more general and flexible framework for the estimation of genetic confounding, LSKM-LASSO is able to provide a more accurate evaluation of the joint effects of multiple genetic variants. Our simulations demonstrate that our approach outperforms three state-of-the-art alternatives in terms of eQTL identification and phenotype prediction. We then apply our method to genotype and gene expression data of 11 tissues obtained from the Genotype-Tissue Expression project. Our algorithm was able to identify more genes with eQTL than other algorithms. By incorporating a regularization term and combining it with least-squares kernel machine, LSKM-LASSO provides a powerful tool for eQTL mapping and phenotype prediction.


Assuntos
Aprendizado de Máquina , Locos de Características Quantitativas/genética , Algoritmos , Fatores de Confusão Epidemiológicos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genótipo , Humanos , Modelos Genéticos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
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