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1.
Nature ; 594(7861): 33-36, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34002091

RESUMEN

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

2.
Clin Radiol ; 79(7): 544-552, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38599951

RESUMEN

BACKGROUND: Left atrial (LA) dysfunction is involved in idiopathic inflammatory myopathy (IIM). Multiparametric cardiovascular magnetic resonance (CMR) strain imaging is a feasible and reproducible tool for examining global and regional LA functions, as well as left ventricular (LV) function in IIM patients. AIM: The aim of this study was to evaluate the feasibility and reproducibility of LA strain occurrence and strain rate for LA function assessment using CMR in IIM cases. MATERIALS AND METHODS: A total of 36 IIM and 42 healthy control cases were included. Baseline ventricular function was comparatively assessed in both groups. LA strain occurrence and strain rate were examined by cine cardiac magnetic resonance imaging [MRI] utilizing an in-house semiautomated technique. LA global function indexes were quantitated, including reservoir, conduit, and booster-pump functions. RESULTS: A total of 78 participants were enrolled in this study. There was no significant difference in left/right ventricular routine functions between IIM patients and control individuals (p>0.05); the same results (p>0.05) was also observed between patients with high hs-cTnI and normal. However, LV mass index had significant difference (p1=0.003, p2<0.01). Compared with IIM patients and control individuals, only total strain (εs) (p4=0.046) and passive strain (εe) (p4=0.002) showed significant difference, and in cases with high hs-cTnI and normal hs-cTnI, there are differences for εs (p3=0.012) and εe (p4=0.047). The strongest association was found between εe and LV ejection fraction (LVEF) (r=0.581, p<0.01). CONCLUSION: IIM cases have altered LA reservoir and conduit functions, and LA strain could reflect LA function.


Asunto(s)
Atrios Cardíacos , Imagen por Resonancia Cinemagnética , Miositis , Humanos , Masculino , Femenino , Miositis/diagnóstico por imagen , Miositis/fisiopatología , Imagen por Resonancia Cinemagnética/métodos , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Adulto , Reproducibilidad de los Resultados , Persona de Mediana Edad , Función del Atrio Izquierdo/fisiología , Estudios de Factibilidad , Estudios de Casos y Controles
3.
Zhonghua Yi Xue Za Zhi ; 104(21): 1998-2002, 2024 Jun 04.
Artículo en Zh | MEDLINE | ID: mdl-38825944

RESUMEN

The study aims to summarize the clinical characteristics of patients with ectopic gastric mucosa in the small intestine, comparing clinical presentation differences between domestic and foreign patients through literature review. The clinical characteristics of cases diagnosed with ectopic gastric mucosa in the small intestine at Peking Union Medical College Hospital from January 2000 to January 2024 were retrospectively analyzed. By searching databanks, such as PubMed, EMBASE, the Cochrane Library, Wanfang, VIP, CNKI, and etc (the inclusion period was from the establishment of the database to January 1, 2024). The literature review was conducted on ectopic gastric mucosa in the small intestine. A total of 10 cases were included, all male, age [M (Q1, Q3)] was 27 (13-69) years old. Gastrointestinal bleeding was the first manifestation in most cases, with severe cases leading to hemorrhagic shock. Abdominal CT indicated local intestinal wall thickening and luminal narrowing in 3 cases. Four cases lesions were located at the beginning of the jejunum and 6 lesions were located in the end segment of ileum. All cases underwent local lesion resection, with postoperative pathology confirming ectopic gastric mucosa. Symptoms disappeared postoperatively, with a follow-up period of 0.5-3.0 years. Literature review indicates that the main clinical manifestation of gastric mucosa ectopia in the small intestine in China is gastrointestinal bleeding, while foreign patients are often complicated with intestinal duplication and intussusception, with abdominal pain and vomiting as the primary and main symptoms. The occurrence rate of intestinal obstruction in female patients, both domestically and abroad, is higher than that in male patients. The occurrence rate of ileal lesions with intestinal obstruction and small intestinal duplication is higher than that of duodenal lesions in both domestic and foreign patients. Local small intestine resection is an effective treatment method with generally good prognosis. Ectopic small intestinal mucosa is relatively rare, with symptoms of gastrointestinal bleeding and intestinal obstruction being common presentations, which can serve as one of the differential diagnoses for unexplained gastrointestinal bleeding.


Asunto(s)
Coristoma , Mucosa Gástrica , Hemorragia Gastrointestinal , Intestino Delgado , Humanos , Mucosa Gástrica/patología , Masculino , Adulto , Persona de Mediana Edad , Adolescente , Anciano , Hemorragia Gastrointestinal/etiología , Adulto Joven , Estudios Retrospectivos , Femenino , China
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(7): 992-997, 2024 Jul 06.
Artículo en Zh | MEDLINE | ID: mdl-39034782

RESUMEN

Objective: To investigate the effects of wza gene deletion in Klebsiella pneumoniae on capsule formation ability and bacteriophage sensitivity. Methods: The wza deletion mutant strain was constructed through a temperature-sensitive plasmid-mediated homologous recombination. The growth curves of W14 and Δwza were detected by measuring the optical density OD600. In order to analyze the effect of gene wza on bacterial capsule formation, wild-type strain W14 and Δwza mutant strain were detected by transmission electron microscope, and their capsule contents were measured by quantifying the uronic acid contents. The plaque assay was used to detect bacterial sensitivity to bacteriophage in wild-type strain W14 and Δwza mutant strain. The t test was used to compare whether there were differences in the contents of uronic acid in the capsules of wild-type strain W14 and Δwza mutant strain. Results: The PCR results revealed that the Δwza mutant strain was successfully constructed. Compared with wild-type strain W14, the growth curves of Δwza on the solid plates demonstrated a slightly slower growth. However, no difference in growth was observed among wild-type strain W14 and Δwza mutant strains in LB broth. The transmission electron microscope results showed that wza gene deletion resulted in the loss of capsule in bacteria. The uronic acid content assay suggested that the capsule content was significantly decreased in Δwza mutant strain (45.963±2.795) µg/ml compared with wild-type strain W14 (138.800±5.201) µg/ml. There was a statistical difference between the two groups (t=27.233, P<0.001). The plaque assay indicated that bacteria lost its sensitivity to bacteriophage when gene wza was deleted. Conclusion: Deletion of the wza gene impairs bacterial capsule formation ability and can affect bacterial sensitivity to bacteriophage phiW14.


Asunto(s)
Cápsulas Bacterianas , Bacteriófagos , Eliminación de Gen , Klebsiella pneumoniae , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/virología , Bacteriófagos/genética , Cápsulas Bacterianas/genética , Proteínas Bacterianas/genética
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(9): 1348-1353, 2024 Sep 06.
Artículo en Zh | MEDLINE | ID: mdl-39290015

RESUMEN

Objective: To express and purify the phage depolymerase from hypervirulent Klebsiella pneumoniae (hvKp) serotype K1 and validate its function. Methods: Phage that infected serotype K1-type hvKp was isolated from hospital sewage. The biology and morphology of the phage were determined by plaque assay and transmission electron microscopy. The whole genome of the phage was sequenced by the Illumina HiSeq 2500 platform. The presence of depolymerase was determined by observing the plaque halo. Bioinformatic analysis and prokaryotic protein expression system were further used to predict and identify phage depolymerase. The depolymerase gene fragment was obtained by PCR and cloned into the pET28a expression vector, and the expression and purification of the depolymerase were completed in strain BL21. The depolymerase activities on the capsular polysaccharide of serotype K1-type hvKp clinical isolates were detected by plaque assay and low-speed centrifugation assay. Results: A lytic phage (phiA2) that infected serotype K1-type hvKp clinical isolate was isolated from hospital sewage. It was typical of the Caudovirales order and Autographiviridae family, and its whole genome was 43 526 bp in length and contained 51 coding domain sequences. The phage phiA2-derived depolymerase phiA2-dep was predicted, expressed and purified. The plaque assay and low-speed centrifugation assay indicated that the depolymerase phiA2-dep had good lytic activity on the capsular polysaccharide of serotype K1-type hvKp clinical isolates. Conclusion: Depolymerase phiA2-dep can specifically degrade the capsular polysaccharide of serotype K1-type hvKp, which has potential application value in treating bacterial infection.


Asunto(s)
Bacteriófagos , Klebsiella pneumoniae , Serogrupo , Klebsiella pneumoniae/genética , Bacteriófagos/genética , Bacteriófagos/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Genoma Viral
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(4): 339-345, 2024 Apr 12.
Artículo en Zh | MEDLINE | ID: mdl-38599809

RESUMEN

Objective: To construct and characterize conditional Src homology region 2 protein tyrosine phosphatase 1 (SHP-1) knockout mice in airway epithelial cells and to observe the effect of defective SHP-1 expression in airway epithelial cells on the emphysema phenotype in chronic obstructive pulmonary disease (COPD). Methods: To detect the expression of SHP-1 in the airway epithelium of COPD patients. CRISPR/Cas9 technology was used to construct SHP-1flox/flox transgenic mice, which were mated with airway epithelial Clara protein 10-cyclase recombinase and estrogen receptor fusion transgenic mice (CC10-CreER+/+), and after intraperitoneal injection of tamoxifen, airway epithelial SHP-1 knockout mice were obtained (SHP-1flox/floxCC10-CreER+/-, SHP-1Δ/Δ). Mouse tail and lung tissue DNA was extracted and PCR amplified to discriminate the genotype of the mice; the knockout effect of SHP-1 gene in airway epithelial cells was verified by qRT-PCR, Western blotting, and immunofluorescence. In addition, an emphysema mouse model was constructed using elastase to assess the severity of emphysema in each group of mice. Results: Airway epithelial SHP-1 was significantly downregulated in COPD patients. Genotyping confirmed that SHP-1Δ/Δ mice expressed CC10-CreER and SHP-1-flox. After tamoxifen induction, we demonstrated the absence of SHP-1 protein expression in airway epithelial cells of SHP-1Δ/Δ mice at the DNA, RNA, and protein levels, indicating that airway epithelial cell-specific SHP-1 knockout mice had been successfully constructed. In the emphysema animal model, SHP-1Δ/Δ mice had a more severe emphysema phenotype compared with the control group, which was manifested by disorganization of alveolar structure in lung tissue and rupture and fusion of alveolar walls to form pulmonary alveoli. Conclusions: The present study successfully established and characterized the SHP-1 knockout mouse model of airway epithelial cells, which provides a new experimental tool for the in-depth elucidation of the role of SHP-1 in the emphysema process of COPD and its mechanism.


Asunto(s)
Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Ratones , Animales , Enfisema Pulmonar/genética , Enfisema Pulmonar/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Células Epiteliales/metabolismo , Ratones Transgénicos , Ratones Noqueados , Fenotipo , ADN , Tamoxifeno
7.
Zhonghua Wai Ke Za Zhi ; 62(2): 172-176, 2024 Feb 01.
Artículo en Zh | MEDLINE | ID: mdl-38310386

RESUMEN

The detection rate of multifocal / multicentric breast cancer (MMBC) is increasing, and the local treatment of MMBC is attracting more attention. Relevant research focuses on the selection of surgical methods, the application of radiotherapy, and the feasibility of local ablation. Currently, due to the high rate of local recurrence in breast conserving surgery, most Chinese doctors recommend mastectomy to patients with MMBC. Recent studies have shown that with the development of imaging technology, surgical techniques, accurate judgment of the resection margin, the emergence of new therapeutic drugs and the improvement of the accuracy of radiotherapy, for eligible patients with MMBC, breast conserving surgery did not increase the local recurrence rate while ensuring negative margin and cosmetic results. Whether patients with MMBC must receive adjuvant radiotherapy after mastectomy is controversial, with some evidence suggesting that MMBC may increase the risk of local recurrence and should be an important consideration for radiotherapy, and there is also evidence that the local recurrence rate of MMBC was higher regardless of the type of surgery. In general, the local treatment modality for MMBC is essentially the same as that for unifocal breast cancer, but more prospective studies are needed for further evaluation.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/cirugía , Mastectomía , Mastectomía Segmentaria , Recurrencia Local de Neoplasia/cirugía , Estudios Prospectivos
8.
Zhonghua Wai Ke Za Zhi ; 62(10): 978-982, 2024 Aug 26.
Artículo en Zh | MEDLINE | ID: mdl-39183024

RESUMEN

An increasing number of studies suggested that the tumor microenvironment exerts a substantial influence on the pathophysiology of pancreatic cancer. As a crucial component of the tumor microenvironment,the tumor stroma plays a pivotal role in the occurrence,development,and chemotherapy resistance of pancreatic cancer. By serving as a proxy for the interaction between tumor cells and the microenvironment,the tumor stroma ratio(TSR) has emerged as a focal point of investigation in recent years. At present,numerous studies show that a low TSR is a protective factor for the prognosis of resectable pancreatic cancer. Additionally, patients with a low TSR are more suitable for the gemcitabine and albumin-bound paclitaxel chemotherapy regimen. But these researches are not conclusive, and there is still a gap between guiding precision treatment. Further research and exploration are required. Integration of artificial intelligence deep learning models into traditional pathological and imaging assessments facilitates precise evaluation of the TSR. It can also enable stratification and precision treatment of pancreatic cancer patients based on this index.

9.
Opt Express ; 31(2): 907-915, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785139

RESUMEN

The potential of frequency comb spectroscopy has aroused great interest in generating mid-infrared frequency combs in the integrated photonic setting. However, despite remarkable progress in microresonators and quantum cascade lasers, the availability of suitable mid-IR comb sources remains scarce. Here, we generate mid-IR microcombs relying on cascaded three-wave-mixing for the first time. By pumping a CdSiP2 microresonator at 1.55 µm wavelength with a low power continuous wave laser, we generate χ(2) frequency combs at 3.1 µm wavelength, with a span of about 30 nm. We observe ordinary combs states with a line spacing of the free spectral range of the resonator, and combs where the sideband numbers around the pump and half-harmonic alternate, forming staggered patterns of spectral lines. Our scheme for mid-IR microcomb generation is compatible with integrated telecom lasers. Therefore, it has the potential to be used as a simple and fully integrated mid-IR comb source, relying on only one single material.

10.
Anal Bioanal Chem ; 415(23): 5605-5617, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37470813

RESUMEN

Mayaro virus (MAYV) is an emerging mosquito-borne alphavirus that causes clinical symptoms similar to those caused by Chikungunya virus (CHIKV), Dengue virus (DENV), and Zika virus (ZIKV). To differentiate MAYV from these viruses diagnostically, we have developed a portable device that integrates sample preparation with real-time, reverse-transcription, loop-mediated isothermal amplification (rRT-LAMP). First, we designed a rRT-LAMP assay targeting MAYV's non-structural protein (NS1) gene and determined the limit of detection of at least 10 viral genome equivalents per reaction. The assay was specific for MAYV, without cross-reactions with CHIKV, DENV, or ZIKV. The rRT-LAMP assay was integrated with a sample preparation device (SPD) wherein virus lysis and RNA enrichment/purification were carried out on the spot, without requiring pipetting, while subsequent real-time amplification device (RAD) enables virus detection at the point of care (POC). The functions of our platform were demonstrated using purified MAYV RNA or blood samples containing viable viruses. We have used the devices for detection of MAYV in as short as 13 min, with limit of detection to as low as 10 GEs/reaction.


Asunto(s)
Virus Chikungunya , Infección por el Virus Zika , Virus Zika , Animales , Humanos , Infección por el Virus Zika/diagnóstico , Virus Zika/genética , Virus Chikungunya/genética , Técnicas de Amplificación de Ácido Nucleico , Genoma Viral , ARN Viral/genética
11.
J Chem Phys ; 158(3): 034506, 2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36681631

RESUMEN

In this paper, we investigate prenucleation and heterogeneous nucleation in the liquid Pb/solid Al system as an example of systems with large lattice misfit using molecular dynamics simulation. Solid Pb and Al have a large positive lattice misfit (f) of 18.2% along the densely packed [110] direction. This study reveals that prenucleation occurs at 600 K (an undercooling of 15 K), and a 2-dimensional (2D) ordered structure forms at the interface with a coincidence site lattice (CSL) between the first Pb and first Al layers. The CSL accommodates the major part of the f, and only a small residual lattice misfit (fr) of 1.9% remains. The formation of the CSL transforms the original substrate into a considerably potent nucleant, where the first Pb layer becomes the new surface layer of the substrate. At an undercooling of about 22 K, nucleation proceeds by merging 2D ordered structure through structural templating: the second Pb layer is epitaxial to the CSL Pb layer, the third Pb layer largely accommodates the fr, and the fourth Pb layer is a nearly perfect crystalline plane. Further analysis indicates that the interface with the CSL has a lower interfacial energy than with a cube-to-cube orientation relationship. For the first time, we established that the CSL was an effective mechanism to accommodate the f for systems with a large positive misfits. Heterogeneous nucleation is governed not by a single mechanism (misfit dislocations in Turnbull's model), but instead by various mechanisms depending on f. This study sheds new light on the atomistic mechanism of heterogeneous nucleation.


Asunto(s)
Plomo , Simulación de Dinámica Molecular
12.
J Stroke Cerebrovasc Dis ; 32(5): 107059, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36842351

RESUMEN

OBJECTIVES: The COVID-19 pandemic has heightened awareness of health disparities associated with socioeconomic status (SES) across the United States. We examined whether household income is associated with functional outcomes after stroke and COVID-19. MATERIALS AND METHODS: This was a multi-institutional, retrospective cohort study of consecutively hospitalized patients with SARS-CoV-2 and radiographically confirmed stroke presenting from March through November 2020 to any of five comprehensive stroke centers in metropolitan Chicago, Illinois, USA. Zip-code-derived household income was dichotomized at the Chicago median. Logistic regression was used to examine the relationship between household income and good functional outcome (modified Rankin Scale 0-3 at discharge, after ischemic stroke). RESULTS: Across five hospitals, 159 patients were included. Black patients comprised 48.1%, White patients 38.6%, and Hispanic patients 27.7%. Median household income was $46,938 [IQR: $32,460-63,219]. Ischemic stroke occurred in 115 (72.3%) patients (median NIHSS 7, IQR: 0.5-18.5) and hemorrhagic stroke in 37 (23.7%). When controlling for age, sex, severe COVID-19, and NIHSS, patients with ischemic stroke and household income above the Chicago median were more likely to have a good functional outcome at discharge (OR 7.53, 95% CI 1.61 - 45.73; P=0.016). Race/ethnicity were not included in final adjusted models given collinearity with income. CONCLUSIONS: In this multi-institutional study of hospitalized patients with stroke, those residing in higher SES zip codes were more likely to have better functional outcomes, despite controlling for stroke severity and COVID-19 severity. This suggests that area-based SES factors may play a role in outcomes from stroke and COVID-19.


Asunto(s)
COVID-19 , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Estados Unidos/epidemiología , COVID-19/terapia , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/terapia , Estudios Retrospectivos , Pandemias , SARS-CoV-2 , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapia , Renta
13.
Zhonghua Zhong Liu Za Zhi ; 45(8): 637-641, 2023 Aug 23.
Artículo en Zh | MEDLINE | ID: mdl-37580267

RESUMEN

Esophageal cancer (EC) is a dreadful disease with a poor prognosis and poses heavy health burden worldwide. Developing effective methods to identify high-risk individuals is urgently needed for preliminary screening before endoscopy. The novel non-endoscopic device has the potential advantages of low cost, simple operation, and minimal invasiveness. Approximately 90% of participants can swallow the device successfully with high safety profiles, and sufficient esophageal exfoliated cells can be collected for cytological examination and biomarker detection. Cytological examination based on the device combined with trefoil factor 3 (TFF3) protein or DNA methylation examinations could effectively screen Barrett's esophagus-associated dysplasia and early esophageal adenocarcinoma, but large prospective studies are needed to further validate the diagnostic value of this device to improve the quality of evidence. Although the device-based cytological examination in combination with biomarker detection holds promise in the early screening of esophageal squamous dysplasia and early esophageal squamous cell carcinoma, related research is still in its infancy, and there is still a lack of sufficient evidence for population screening in China. Active research into the application of this novel non-endoscopic device in EC screening and early diagnosis is of great significance for optimizing EC screening strategies and improving the early diagnosis of EC.


Asunto(s)
Esófago de Barrett , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patología , Detección Precoz del Cáncer , Esófago de Barrett/diagnóstico , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Biomarcadores/análisis , Esofagoscopía
14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(3): 341-347, 2023 Mar 06.
Artículo en Zh | MEDLINE | ID: mdl-36922168

RESUMEN

Oral allergy syndrome (OAS) is an IgE-mediated hypersensitivity. Patients with pollen allergy will experience oropharyngeal allergy after eating fresh fruits or vegetables containing homologous pathogenesis-related allergen, occasionally accompanied by systemic symptoms, it is a special type of food hypersensitivity in which respiratory allergens and food allergens are similar structurally and lead to the cross-reactivity. At present, there is little research and attention to it in China. To master the definition, epidemiological characteristics, pathological mechanism, diagnosis, prevention and treatment of OAS is very important to the prevention and control of OAS. This article reviews the research progress of OAS, providing reference and prevention basis for clinicians to improve the diagnosis and differential diagnosis of OAS.


Asunto(s)
Hipersensibilidad a los Alimentos , Rinitis Alérgica Estacional , Humanos , Polen , Hipersensibilidad a los Alimentos/diagnóstico , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/terapia , Alérgenos , Frutas , Reacciones Cruzadas
15.
Zhonghua Gan Zang Bing Za Zhi ; 31(8): 869-876, 2023 Aug 20.
Artículo en Zh | MEDLINE | ID: mdl-37723070

RESUMEN

Objective: To screen the pivotal genes involved in the occurrence and development of HBV-associated HCC. Additionally, perform validation and biological function analysis to evaluate changes in the expression of pivotal genes and their prognostic value in patients with hepatocellular carcinoma. Methods: The GSE121248 gene expression profile data of HBV-HCC patients were searched and downloaded from the GEO database. The R language was used to compare the differences in gene expression between hepatocellular carcinoma and paracancerous tissues. KEGG and GO function enrichment analyses were performed on the differential genes. PPI plots and pivotal gene screening were carried out through online tools like STRING and Cytoscape software. 369 cases of hepatocellular carcinoma and 160 healthy controls in TCGA and GTEx were used as validation cohorts to verify the expression levels of the pivotal genes. A Kaplan-Meier plot was drawn to evaluate the prognostic value of the pivotal gene. Results: A total of 120 differentially expressed genes were screened, of which 89 were up-regulated and 31 were down-regulated. Differential genes were mainly enriched in the metabolic pathways related to retinol metabolism, cytochrome P450 metabolism, and the p53 signaling pathway. The top 10 differential genes were selected as pivotal genes by the Cytoscape plug-in cytoHubba. There were significant differences in the expression levels of four types of CCNB1, CDK1, RRM2, and TOP2A genes in the validation cohort. All four types of genes were up-regulated. Survival analysis showed that patients with elevated expression levels of four genes had a poorer prognosis, with statistical differences in results. Conclusion: Four types of genes, CCNB1, CDK1, RRM2, and TOP2A, have high expression levels in patients with HBV-HCC and are correlated to shorter survival times, making them a potential target for diagnosis, prognosis, and treatment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Virus de la Hepatitis B , Neoplasias Hepáticas/genética , Bases de Datos Factuales
16.
Zhonghua Gan Zang Bing Za Zhi ; 31(8): 842-846, 2023 Aug 20.
Artículo en Zh | MEDLINE | ID: mdl-37723066

RESUMEN

Objective: intrahepatic portocaval shunt (TIPS) in the treatment of hepatic sinusoidal obstruction syndrome (HSOS). Methods: A retrospective analysis was performed on 27 patients with HSOS who were treated with TIPS in our center from July 2018 to July 2020. The changes of portal vein pressure (PVP), portal vein pressure gradient (PPG) and liver function were observed, so as to evaluate the efficacy. Paired t test was adopted to evaluate the quantitative parameters, while χ (2) test was used to analyze qualitative parameters, with P < 0.05 as statistical difference. Results: PVP decreased from (4.41 ± 0.18) kPa before shunt to (2.69 ± 0.11) kPa after shunt (t = 82.41, P < 0.001), PPG decreased from (3.23 ± 0.18) kPa before shunt to (1.46 ± 0.23) kPa after shunt (t = 32.41, P < 0.001). The liver function improved significantly after operation. After 24 months of follow-up, 3 patients developed stent restenosis and recanalized after balloon dilation. Three patients developed hepatic encephalopathy, which was improved after drug treatment. One patient underwent liver transplantation due to liver failure. Conclusion: TIPS is effective in the treatment of HSOS in the short and medium term, and can provide time for liver transplantation patients to wait for liver source.


Asunto(s)
Encefalopatía Hepática , Enfermedad Veno-Oclusiva Hepática , Hepatopatías , Humanos , Estudios Retrospectivos
17.
Phys Rev Lett ; 128(5): 051102, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35179919

RESUMEN

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.

18.
Phys Rev Lett ; 129(26): 261103, 2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36608208

RESUMEN

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.

19.
Clin Radiol ; 77(3): e241-e249, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35042612

RESUMEN

AIM: To assess the predictive value of major adverse cardiac events (MACEs) in patients with acute myocardial infarction (AMI) by T2-mapping texture analysis (TA) of the myocardial remote zone. MATERIALS AND METHODS: Data from 155 patients, who were diagnosed with AMI and were treated with primary percutaneous coronary intervention (PPCI), and 32 healthy controls who underwent cardiac magnetic resonance imaging (CMRI) were analysed retrospectively. T2-mapping TA of the myocardial remote zone was conducted accordingly. The patients were divided into two subgroups according to the occurrence of MACEs. The primary outcome was a composite of MACEs. RESULTS: Among 155 patients, 32 (20.6%) patients suffered MACEs, and the most common event was non-sustained ventricular tachycardia (84.3%). Five independent texture features on T2-mapping were selected: Perc.50%, S(4,-4)AngScMom, S(1,1)InvDfMom, S(0,2)DifEntrp, and Horzl_LngREmph. Among them, the mean value of Horzl_LngREmph in the myocardial remote zone among all patients, MACEsnegative, and MACEs-positive was 21.64, 19.12, and 34.52, respectively. Horzl_LngREmph provided the highest area under the receiver operating characteristic (ROC) curve (AUC) value, which enabled two subgroups to be distinguished (AUC = 0.914, p<0.05). According to the results of the univariate analysis, combined with late gadolinium enhancement (LGE) extent and the presence of left ventricular hypertrophy, Horzl_LngREmph, was strongly associated with the occurrence of MACEs (p<0.05, hazard ratio: 1.64, 95% confidence interval: 1.10-4.51). CONCLUSION: Together with LGE extent, Horzl_LngREmph, a texture feature obtained from T2-mapping TA of the myocardial remote zone, could predict the occurrence of MACEs in AMI patients.


Asunto(s)
Corazón/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Infarto del Miocardio/diagnóstico por imagen , Anciano , Estudios de Casos y Controles , Femenino , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/patología , Infarto del Miocardio/cirugía , Miocardio/patología , Intervención Coronaria Percutánea , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Accidente Cerebrovascular/etiología , Taquicardia Ventricular/etiología
20.
J Aerosol Sci ; 165: 106038, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35774447

RESUMEN

The B.1.617.2 (Delta) variant of SARS-CoV-2 emerged in India in October of 2020 and spread widely to over 145 countries, comprising over 99% of genome sequence-confirmed virus in COVID-19 cases of the United States (US) by September 2021. The rise in COVID-19 cases due to the Delta variant coincided with a return to in-person school attendance, straining COVID-19 mitigation plans implemented by educational institutions. Some plans required sick students to self-isolate off-campus, resulting in an unintended consequence: exposure of co-inhabitants of dwellings used by the sick person during isolation. We assessed air and surface samples collected from the bedroom of a self-isolating university student with mild COVID-19 for the presence of SARS-CoV-2. That virus' RNA was detected by real-time reverse-transcription quantitative polymerase chain reaction (rRT-qPCR) in air samples from both an isolation bedroom and a distal, non-isolation room of the same dwelling. SARS-CoV-2 was detected and viable virus was isolated in cell cultures from aerosol samples as well as from the surface of a mobile phone. Genomic sequencing revealed that the virus was a Delta variant SARS-CoV-2 strain. Taken together, the results of this work confirm the presence of viable SARS-CoV-2 within a residential living space of a person with COVID-19 and show potential for transportation of virus-laden aerosols beyond a designated isolation suite to other areas of a single-family home.

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