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1.
Lancet Infect Dis ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33031750

RESUMO

BACKGROUND: Since 1997, epidemics of hand, foot, and mouth disease associated with enterovirus A71 (EV-A71) have affected children younger than 5 years in the Asia-Pacific region, including mainland China. EV-A71 vaccines have been licensed for use in children aged 6-71 months in China, but not for infants younger than 6 months. We aimed to assess the dynamics of maternal EV-A71 antibodies to inform choice of potential vaccination strategies to protect infants younger than 6 months, because they have a substantial burden of disease. METHODS: We did a longitudinal cohort study with mother-neonate pairs in local hospitals in southern China during 2013-18. We collected cord blood from neonates and venous blood from mothers at delivery. We followed up and collected blood samples from the children at ages 2, 4, 6, 12, 24, and 36 months and tested for the presence of neutralising antibodies against EV-A71 with virus neutralisation assays. Seropositivity, or protective titre, was defined as a neutralisation antibody titre of 16 or higher. We estimated the seroprevalence, geometric mean titre (GMT), and transfer ratio of maternal antibodies. We used a binomial distribution to derive the 95% CIs of seroprevalence. Seropositivity between mothers and neonates was compared by use of an agreement (κ), while GMTs were compared by use of paired Student's t tests. FINDINGS: Between Sept 20, 2013, and Oct 14, 2015, 1054 mothers with 1066 neonates were enrolled. The EV-A71 GMT was similar among pairs of neonates (22·7, 95% CI 20·8-24·9) and mothers (22·1, 95% CI 20·2-24·1; p=0·20). The mean transfer ratio of maternal antibodies was 1·03 (95% CI 0·98-1·08). Although 705 (66%) of 1066 neonates acquired protective concentrations of EV-A71 antibodies from mothers, these declined rapidly, with a half-life of 42 days (95% CI 40-44). The time to loss of protective immunity was extended to 5 months in neonates with mothers who had titres of 128 or higher. By age 30 months, 28% of children had become seropositive because of natural infection. INTERPRETATION: EV-A71 maternal antibodies were efficiently transferred to neonates, but declined quickly to below the protective threshold, particularly among those whose mothers had low antibody titres. Our findings suggest that maternal vaccination could be explored to provide neonatal protection against EV-A71 through maternal antibodies. Catch-up vaccination between ages 6 months to 5 years could provide protection to the approximately 30-90% of children that have not had natural EV-A71 infection by that age. FUNDING: National Science Fund for Distinguished Young Scholars, National Natural Science Foundation of China.

2.
Clin Nutr ; 2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-33008652

RESUMO

BACKGROUND & AIMS: Our previous study found that platelet counts were positively associated with body fat percentage in human. In the present study, we conducted a reverse translational study to explore the role of platelets in modulating pre-adipocyte proliferation in mice. METHODS: Mouse pre-adipocyte cell line (3T3-L1) and human pre-adipocytes harvested from female subcutaneous fat were used. Pre-adipocytes were co-cultured with platelets or platelet releasate, which were isolated from mice or humans. The cell viability and proliferative ability of the pre-adipocytes were examined by MTT and flow cytometry assays. Western blotting analysis was used to determine the phosphorylation levels of proteins in the mTOR pathway. RESULTS: The number of platelets in the adipose tissues from obese mice was significantly higher than that from lean mice. Platelets and collagen-activated platelet releasate stimulated the proliferation of human pre-adipocytes and 3T3-L1 cells in vitro. Besides, platelets from obese mice were more potent in stimulating pre-adipocyte proliferation than those from lean control mice. Mechanistically, platelets enhanced pre-adipocyte proliferation through the acceleration of cell cycle progression from G0/G1 to S phase cell cycle progression. At the molecular level, platelets promoted pre-adipocyte proliferation through mTOR pathway-mediated upregulation of cyclin D1 expression. CONCLUSION: In conclusion, platelets and platelet releasate play an important role in the proliferation of pre-adipocytes. Our study may provide new clues and the molecular mechanism of the causal pathways between platelets and body fat to explain the finding we observed in population study.

3.
J Genet Genomics ; 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-33023834

RESUMO

Integration of human papillomavirus (HPV) DNA into the human genome is a reputed key driver of cervical cancer. However, the effects of HPV integration on chromatin structural organization and gene expression are largely unknown. We studied a cohort of 61 samples and identified an integration hot spot in the CCDC106 gene on chromosome 19. We then selected fresh cancer tissue that contained the unique integration loci at CCDC106 with no HPV episomal DNA and performed whole-genome, RNA, chromatin immunoprecipitation and high-throughput chromosome conformation capture (Hi-C) sequencing to identify the mechanisms of HPV integration in cervical carcinogenesis. Molecular analyses indicated that chromosome 19 exhibited significant genomic variation and differential expression densities, with correlation found between three-dimensional (3D) structural change and gene expression. Importantly, HPV integration divided one topologically associated domain (TAD) into two smaller TADs and hijacked an enhancer from PEG3 to CCDC106, with a decrease in PEG3 expression and an increase in CCDC106 expression. This expression dysregulation was further confirmed using 10 samples from our cohort, which exhibited the same HPV-CCDC106 integration. In summary, we found that HPV-CCDC106 integration altered local chromosome architecture and hijacked an enhancer via 3D genome structure remodeling. Thus, this study provides insight into the 3D structural mechanism underlying HPV integration in cervical carcinogenesis.

4.
BMJ Open ; 10(10): e040910, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033099

RESUMO

OBJECTIVE: To investigate psychological and behavioural responses to COVID-19 among the Chinese general population. DESIGN, SETTING AND PARTICIPANTS: We conducted a population-based mobile phone survey between 1 February and 10 February 2020 via random digit dialling. A total of 1011 adult residents in Wuhan (n=510), the epicentre and quarantined city, and Shanghai (n=501) were interviewed. Proportional quota sampling and poststratification weighting were used. Multivariable logistic regression models were used to investigate perception factors associated with the public responses. PRIMARY OUTCOME MEASURES: We measured anxiety levels using the 7-item Generalised Anxiety Disorder Scale (GAD-7) and asked respondents to report their precautionary behaviours before and during the outbreak. RESULTS: The prevalence of moderate or severe anxiety was significantly higher (p<0.001) in Wuhan (32.8%) than Shanghai (20.5%). Around 79.6%-88.2% residents reported always wearing a face mask when they went out and washing hands immediately when they returned home, with no discernible difference across cities. Only 35.5%-37.0% of residents reported a handwashing duration above 40 s as recommended by the WHO. The strongest predictor of moderate or severe anxiety was perceived harm of the disease (OR 1.8, 95% CI 1.5 to 2.1), followed by confusion about information reliability (OR 1.7, 95% CI 1.5 to 1.9). None of the examined perception factors were associated with odds of handwashing duration above 40 s. CONCLUSIONS: Prevalence of moderate or severe anxiety and strict personal precautionary behaviours was generally high, regardless of the quarantine status. Our results support efforts for handwashing education programmes with a focus on hygiene procedures in China and timely dissemination of reliable information.

5.
Brain Res ; 1749: 147136, 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32980332

RESUMO

Fear-related anxiety disorders, such as social phobia and post-traumatic stress disorder, are partly explained by an uncontrollable state of fear. An emerging literature suggests dopamine receptor-1 (D1 receptor) in the amygdala is involved in the regulation of fear memory. An early study has reported that amygdaloid D1 receptor (D1R) is not coupled to the classic cAMP-dependent signal transduction. Here, we investigated whether SKF83959, a typical D1R agonist that mainly activates a D1-like receptor-dependent phosphatidylinositol (PI) signal pathway, facilitates fear extinction and reduces the return of extinguished fear. Interestingly, long-term loss of fearful memories can be induced through a combination of SKF83959 (1 mg/kg/day, i.p., once daily for one week) pharmacotherapy and extinction training. Furthermore, sub-chronic administration of SKF83959 after fear conditioning reduced fear renewal and reinstatement in the mice. We found that the activation D1R and PI signaling in the amygdala was responsible for the effect of SKF83959 on fear extinction. Additionally, SKF83959 significantly promoted the elevation of brain-derived neurotrophic factor (BDNF) expression, possibly by the cAMP response element binding protein (CREB) -directed gene transcription. Given the beneficial effects on extinction, SKF83959 may emerge as a candidate pharmacological approach for improving cognitive-behavioral therapy on fear-related anxiety disorders.

6.
Int J Nanomedicine ; 15: 6409-6420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922008

RESUMO

Aim: Tumor cell-derived microparticles (MP) can function as a targeted delivery carrier for anti-tumor drugs. Here, we aimed to generate paclitaxel-loaded microparticles (MP-PTX) from HeLa cells and examined its therapeutic potential on human cervical carcinoma. Methods: MP-PTX was generated from HeLa cells by ultraviolet radiation and subsequent centrifugation. The particle size, drug loading rate, and stability of MP-PTX were examined in vitro. Flow cytometry and the MTT assay were performed to test the inhibitory effect of MP-PTX using different cell lines. Immunodeficient mice bearing HeLa cervical carcinoma were treated with 0.9% normal saline, MP, paclitaxel (PTX) (2.5 mg/kg), or MP-PTX (PTX content identical to PTX group) every day for 6 consecutive days. Tumor volume and animal survival were observed. Micro 18F-FDG PET/CT was performed to monitor the therapeutic efficacy. The proliferation activity of cells and microvessel density in tumor tissues were determined by immunohistochemical staining using Ki-67 and CD31, respectively. Results: Dynamic laser scattering measurements showed that the particle size of MP-PTX was 285.58 ± 2.95 nm and the polydispersity index was 0.104 ± 0.106. And the particle size of MP-PTX was not change at 4°C for at least one week. More than 1% of PTX in the medium could be successfully encapsulated into HeLa cell-derived MP. When compared with PTX, MP-PTX treatment significantly increased apoptosis of tumor cells and reduced their proliferation. In addition, MP-PTX showed lower toxicity to normal human umbilical vein endothelial cells (HUVEC) than PTX. In vivo studies further demonstrated that MP-PTX treatment significantly inhibited the growth of cervical carcinoma, prolonged the survival of tumor-bearing mice, and reduced the toxicity of PTX. Immunohistochemical staining revealed that MP-PTX treatment led to decreased Ki-67 positive tumor cells and decreased microvessel density in tumor tissues. Conclusion: Our results demonstrated that HeLa-derived MP-PTX significantly enhanced the anti-cancer effects of PTX with reduced toxicity, which may provide a novel strategy for the treatment of cervical carcinoma.

7.
ACS Comb Sci ; 22(10): 495-499, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-32985878

RESUMO

Multicomponent Petasis reaction has been widely applied for the synthesis of functionalized amine building blocks and biologically active compounds. Employing primary aromatic amines that are not typical reactive substrates contributes to expand the application scope of the Petasis reaction. In this study, we demonstrated the synthesis of functionalized 2-aminothiophenes using Gewald-reaction-derived 2-aminothiophenes as the amine substrates, whose low reactivity in the Petasis reaction was overcome using hexafluoro-2-propanol as the solvent in a mild condition. The obtained Petasis products are amenable for further transformations owing to the presence of multiple functional handles. A following intramolecular cyclization of selected Petasis products afforded substituted tricyclic heterocycles that incorporate a pharmaceutically interesting thienodiazepine moiety.

8.
Biosens Bioelectron ; 169: 112603, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32947082

RESUMO

Peroxidase-like DNAzymes have been extensively used to replace horseradish peroxidase (HRP) for developing biosensors for signal amplification. However, the background activity from the cofactor (i.e., free hemin) has limited the sensitivity of such sensors. Herein, we aim to find an inhibitor for hemin to suppress the background signal, and a classic split DNAzyme-based sensor was used to detect a complementary DNA oligonucleotide. After screening a series of dyes, SYBR Green I (SG, one of the DNA stanning dyes) was selected for suppressing the background. Simply by adding 0.84 µM SG, the background from 50 nM hemin was suppressed over 30-fold. The suppression was caused by the interaction between SG and hemin. In the presence of the target DNA, the formed duplex region and G-quadruplex structure can better bind SG and hemin respectively, thus preventing the interaction between them and showing a high activity of the DNAzyme. The optimized sensor showed a detection limit of 3.8 pM for the target DNA (p53 gene). In addition, the backgrounds from chemiluminescence, colorimetric and fluorescence sensing modes can all be reduced by adding SG to the split DNAzyme system. The suppression of the background of peroxidase DNAzymes is a critical step towards practical use of related biosensors.

9.
Cytokine ; 136: 155296, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32947150

RESUMO

BACKGROUND: Published studies on association between IL12B (G/A) rs10045431, (T/C)rs6887695 polymorphisms and inflammatory bowel disease (IBD) risk in Caucasian population have yielded conflicting results. The aim of this study was to potentially provide more reliable conclusions by conducting a meta-analysis. METHODS: Published studies concerned association between IL12B rs10045431, rs6887695 polymorphisms and IBD were searched from the Wiley Online Library, PubMed, Web of Science and the CNKI database. The odds ratio (OR) with 95% confidence interval (CI) was calculated to evaluate the strength of the relationship. The false positive report probabilities (FPRPs) test and trial sequential analysis (TSA) was performed to investigated the reliability of results. RESULTS: A total of 20 studies comprising 10761 Crohn's disease (CD), 10921 ulcerative colitis (UC) and 18381 controls were included in this meta-analysis. Overall, the pooled results showed that IL12B rs6887695 polymorphism significantly increased both CD and UC risk under all model, while IL12B rs10045431 polymorphism dramatically decreased both CD and UC risk under all model. FPRP and TSA demonstrated that above associations was confirmed in the present study. CONCLUSION: The results of meta-analysis indicate IL12B rs10045431 and rs6887695 polymorphisms significantly associate with IBD in Caucasian population.

10.
Math Biosci Eng ; 17(4): 2936-2949, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32987508

RESUMO

The coronavirus disease 2019 (COVID-2019), a newly emerging disease in China, posed a public health emergency of China. Wuhan is the most serious affected city. Some measures have been taken to control the transmission of COVID-19. From Jan. 23rd, 2020, gradually increasing medical resources (such as health workforce, protective clothing, essential medicines) were sent to Wuhan from other provinces, and the government has established the hospitals to quarantine and treat infected individuals. Under the condition of sufficient medical resources in Wuhan, late-stage of epidemic showed a downward trend. Assessing the effectiveness of medical resources is of great significance for the future response to similar disease. Based on the transmission mechanisms of COVID-19 and epidemic characteristics of Wuhan, by using time-dependent rates for some parameters, we establish a dynamical model to reflect the changes of medical resources on transmission of COVID-19 in Wuhan. Our model is applied to simulate the reported data on cumulative and new confirmed cases in Wuhan from Jan. 23rd to Mar. 6th, 2020. We estimate the basic reproduction number R0 = 2.71, which determines whether the disease will eventually die out or not under the absence of effective control measures. Moreover, we calculate the effective daily reproduction ratio Re(t), which is used to measure the 'daily reproduction number'. We obtain that Re(t) drops less than 1 since Feb. 8th. Our results show that delayed opening the 'Fire God Hill' hospital will greatly increase the magnitude of the outbreak. This shows that the government's timely establishment of hospitals and effective quarantine via quick detection prevent a larger outbreak.


Assuntos
Betacoronavirus , Infecções por Coronavirus/transmissão , Modelos Biológicos , Pandemias , Pneumonia Viral/transmissão , Número Básico de Reprodução/estatística & dados numéricos , China/epidemiologia , Simulação por Computador , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Arquitetura Hospitalar , Hospitais , Humanos , Conceitos Matemáticos , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Quarentena/estatística & dados numéricos , Fatores de Tempo
11.
Anal Methods ; 12(19): 2434-2442, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32930232

RESUMO

Covalent organic frameworks with tunable porous crystallinity and outstanding stability have recently exhibited fascinating pretreatment performance as solid-phase microextraction coatings. In this report, a ß-ketoenamine-linked covalent organic framework (TpPa-1) was successfully constructed through a Schiff-base-type reaction between 1,3,5-triformylphloroglucinol (Tp) and para-phenylenediamine (Pa-1). A TpPa-1 coating was then fabricated on a stainless-steel fiber for capturing trace synthetic musks. This TpPa-1 coating exhibited strong interaction with synthetic musks because of its hydrophobicity and π-π affinity. This TpPa-1-based solid-phase microextraction methodology, coupled with gas chromatography-tandem mass spectrometry, provided high enrichment factors (1214-12 487), wide linearity (0.5-1000 ng L-1), low limits of detection (0.04-0.31 ng L-1), and acceptable reproducibility (relative standard deviation, <10%) for nine synthetic musks. Recoveries at three spiked levels in three types of water samples were between 76.2% and 118.7%. These results indicated the promising applicability of the TpPa-1 as a solid-phase microextraction fiber coating for reliably detecting trace concentrations of synthetic musks in the environment.

12.
J Immunol ; 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32989094

RESUMO

Tumor-associated macrophages (TAMs) play a critical role in the tumor inflammatory microenvironment and facilitate tumor growth and metastasis. Most types of tumors aberrantly express microRNAs (miRNAs), which can be transferred between cells by exosomes and can regulate gene expression in recipient cells, but it remains unclear whether tumor-derived miRNAs are transferred by exosomes and regulate the TAM phenotype. We report that mouse 4T1 breast cancer cell-derived exosomes enhanced TAM expression of IL-1ß, IL-6, and TNF-α and that inhibition of 4T1-cell exosome secretion through short hairpin RNA-mediated Rab27a/b depletion repressed tumor growth and metastasis and markedly downregulated IL-1ß, IL-6, and TNF-α in a 4T1 breast tumor model. Furthermore, miRNA expression profiling revealed that three miRNAs (miR-100-5p, miR-183-5p, and miR-125b-1-3p) were considerably more abundant in 4T1 cell exosomes than in mouse bone marrow-derived macrophages, indicating potential exosome-mediated transfer of the miRNAs, and, notably, miR-183-5p was found to be transferred from 4T1 cells to macrophages through exosomes. Moreover, PPP2CA was verified as an miR-183-5p target gene, and PPP2CA downregulation enhanced NF-κB signaling and promoted macrophage expression of IL-1ß, IL-6, and TNF-α. Lastly, when miR-183-5p was downregulated in exosomes through miR-183-5p sponge expression in 4T1 cells, these 4T1-derived exosomes triggered diminished p65 phosphorylation and IL-1ß, IL-6, and TNF-α secretion, and the miRNA downregulation also led to repression of tumor growth and metastasis in the 4T1 breast tumor model in vivo. Thus, miR-183-5p expressed in tumor cells was transferred to macrophages by exosomes and promoted the secretion of proinflammatory cytokines by inhibiting PPP2CA expression, which contributed to tumor progression in a breast cancer model.

13.
Biotechnol Lett ; 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32989662

RESUMO

OBJECTIVES: The capsid protein (VP1) of the foot-and-mouth (FMD) AKT-III strain was expressed on the surface of the T7 phage capsid (AKT-T7 strain) and the potential of AKT-T7 strain as an FMD vaccine was evaluated. RESULTS: The AKT-T7 strain was successfully constructed and was not cytotoxic to BHK-21, MDBK, or sheep kidney cells. The AKT-T7 strain was well phagocytosed by mouse macrophages. Immunization of BALB/c mice revealed that animals were quickly induced and produced high levels of FMDV antibodies. Monitoring data indicated that FMDV antibody levels could be maintained at higher levels for longer periods of time. The AKT-T7 strain induced high levels of IFN-γ levels in mice with little effect on IL-4. CONCLUSIONS: The AKT-T7 induced the mice to produce FMDV antibodies, which has the advantage of phage and FMDV, and is a potential candidate for an FMD vaccine.

14.
J Sep Sci ; 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32864882

RESUMO

An accurate and sensitive ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry method was established and validated for the determination of nine bioactive compounds of Ligustri Lucidi Fructus in rat plasma. Separation was performed on Halo® C18 column with a mobile phase of acetonitrile and 0.1% formic acid in water. The eluate was detected by multiple reaction monitoring scanning operating in the negative ionization mode. This assay method was validated for selectivity, linearity, intra- and interday precision, accuracy, recovery, matrix effect, and stability, and all methodological parameters fulfilled the Food and Drug Administration criteria for bioanalytical validation. The established method was successfully applied to a comparative pharmacokinetic study of raw and wine-processed Ligustri Lucidi Fructus in rats for the first time. It was found that the AUC0-24 and Cmax value of salidroside, hydroxytyrosol, and nuezhenidic acid were increased significantly after processing, while the AUC0-24 and Cmax value of oleoside 11-methyl ester, 1'''-O-ß-d-glucosylformoside, specnuezhenide, G13, oleonuezhenide, and oleanolic acid were decreased, which suggested that processing affects the absorption and bioavailability of Ligustri Lucidi Fructus. The results might be valuable for the clinical reasonable application and understanding the processing mechanism of Ligustri Lucidi Fructus.

16.
Pharm Biol ; 58(1): 969-978, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32956609

RESUMO

CONTEXT: Sibiricose A5 (A5), sibiricose A6 (A6), 3,6'-disinapoyl sucrose (DSS), tenuifoliside A (TFSA) and 3,4,5-trimethoxycinnamic acid (TMCA) are the main active components of Polygala tenuifolia Willd. (Polygalaceae) (PT) that are active against Alzheimer's disease. OBJECTIVE: To compare the pharmacokinetics and bioavailability of five active components in the roots of raw PT (RPT), liquorice-boiled PT (LPT) and honey-stir-baked PT (HPT). MATERIALS AND METHODS: The median lethal dose (LD50) was evaluated through acute toxicity test. The pharmacokinetics of five components after oral administration of extracts of RPT, LPT, HPT (all equivalent to 1.9 g/kg of RPT extract for one dose) and 0.5% CMC-Na solution (control group) were investigated, respectively, in Sprague-Dawley rats (four groups, n = 6) using UHPLC-MS/MS. In addition, the absolute bioavailability of A5, A6, DSS, TFSA and TMCA after oral administration (7.40, 11.60, 16.00, 50.00 and 3.11 mg/kg, respectively) and intravenous injection (1/10 of the corresponding oral dose) in rats (n = 6) was studied. RESULTS: The LD50 of RPT, LPT and HPT was 7.79, 14.55 and 15.99 g/kg, respectively. AUC 0- t of RPT, LPT and HPT were as follows: A5 (433.18 ± 65.48, 680.40 ± 89.21, 552.02 ± 31.10 ng h/mL), A6 (314.55 ± 62.73, 545.76 ± 123.16, 570.06 ± 178.93 ng h/mL) and DSS (100.30 ± 62.44, 232.00 ± 66.08, 197.58 ± 57.37 ng h/mL). The absolute bioavailability of A5, A6, DSS, TFSA and TMCA was 3.25, 2.95, 2.36, 1.17 and 42.91%, respectively. DISCUSSION AND CONCLUSIONS: The pharmacokinetic and bioavailability parameters of each compound can facilitate future clinical studies.

17.
Radiology ; : 200478, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32960726

RESUMO

Background The 2019 Bosniak classification (version 2019) of cystic renal masses (CRMs) provides a systematic update to the currently used 2005 Bosniak classification (version 2005). Further validation is required before widespread application. Purpose To evaluate the interobserver agreement of MRI criteria, the impact of readers' experience, and the diagnostic performance between version 2019 and version 2005. Materials and Methods From January 2009 to December 2018, consecutive patients with CRM who had undergone renal MRI and surgical-pathologic examination were included in this retrospective study. On the basis of version 2019 and version 2005, all CRMs were independently classified by eight radiologists with different levels of experience. By using multirater κ statistics, interobserver agreement was evaluated with comparisons between classifications and between senior and junior radiologists. Diagnostic performance between classifications by dichotomizing classes I-IV into lower (I-IIF) and higher (III-IV) classes was compared by using the McNemar test. P < .05 was considered to indicate a statistically significant difference. Results A total of 207 patients (mean age ± standard deviation, 49 years ± 12; 139 male and 68 female patients) with CRMs were included. Overall, interobserver agreement was higher with version 2019 than version 2005 (weighted κ = 0.64 vs 0.50, respectively; P < .001). Interobserver agreement between senior and junior radiologists did not differ between version 2019 (weighted κ = 0.65 vs 0.64, respectively; P = .71) and version 2005 (weighted κ = 0.54 vs 0.46; P < .001). Diagnostic specificity for malignancy was higher with version 2019 than with version 2005 (83% [92 of 111] vs 68% [75 of 111], respectively; P < .001), without any difference in sensitivity (89% [85 of 96] vs 84% [81 of 96]; P = .34). Conclusion In the updated Bosniak classification, interobserver agreement improved and was unaffected by observers' experience. The diagnostic performance with version 2019 was superior to that with version 2005, with higher specificity. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Choyke in this issue.

19.
Nat Med ; 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943787

RESUMO

Superspreading events (SSEs) have characterized previous epidemics of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) infections1-6. For SARS-CoV-2, the degree to which SSEs are involved in transmission remains unclear, but there is growing evidence that SSEs might be a typical feature of COVID-197,8. Using contact tracing data from 1,038 SARS-CoV-2 cases confirmed between 23 January and 28 April 2020 in Hong Kong, we identified and characterized all local clusters of infection. We identified 4-7 SSEs across 51 clusters (n = 309 cases) and estimated that 19% (95% confidence interval, 15-24%) of cases seeded 80% of all local transmission. Transmission in social settings was associated with more secondary cases than households when controlling for age (P = 0.002). Decreasing the delay between symptom onset and case confirmation did not result in fewer secondary cases (P = 0.98), although the odds that an individual being quarantined as a contact interrupted transmission was 14.4 (95% CI, 1.9-107.2). Public health authorities should focus on rapidly tracing and quarantining contacts, along with implementing restrictions targeting social settings to reduce the risk of SSEs and suppress SARS-CoV-2 transmission.

20.
Chem Commun (Camb) ; 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32945825

RESUMO

Correction for 'Structural reconstruction: a milestone in the hydrothermal synthesis of highly active Sn-Beta zeolites' by Zhiguo Zhu et al., Chem. Commun., 2017, 53, 12516-12519, DOI: 10.1039/C7CC06778J.

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