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A critical spintronics challenge is to develop molecular wires that render efficiently spin-polarized currents. Interplanar torsional twisting, driven by chiral binucleating ligands in highly conjugated molecular wires, gives rise to large near-infrared rotational strengths. The large scalar product of the electric and magnetic dipole transition moments ([Formula: see text]), which are evident in the low-energy absorptive manifolds of these wires, makes possible enhanced chirality-induced spin selectivity-derived spin polarization. Magnetic-conductive atomic force microscopy experiments and spin-Hall devices demonstrate that these designs point the way to achieve high spin selectivity and large-magnitude spin currents in chiral materials.
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The front cover artwork is provided by Prof. Ron Naaman's group at the Weizmann Institute of Science. The image shows that direct electron transfer through GOx is governed by electron spins, which result from the chiral-induced spin selectivity (CISS) effect. Read the full text of the Research Article at 10.1002/cphc.202400033.
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Glucose Oxidase , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Transporte de Elétrons , Biocatálise , ElétronsRESUMO
The reaction of D-glucose oxidase (GOx) with D- and L-glucose was investigated using confocal fluorescence microscopy and Hall voltage measurements, after the enzyme was adsorbed as a monolayer. By adsorbing the enzyme on a ferromagnetic substrate, we verified that the reaction is spin dependent. This conclusion was supported by monitoring the reaction when the enzyme is adsorbed on a Hall device that does not contain any magnetic elements. The spin dependence is consistent with the chiral-induced spin selectivity (CISS) effect; it can be explained by the improved fidelity of the electron transfer process through the chiral enzyme due to the coupling of the linear momentum of the electrons and their spin. Since the reaction studied often serve as a model system for enzymatic activity, the results may suggest the general importance of the spin-dependent electron transfer in bio-chemical processes.
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Glucose Oxidase , Glucose , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Glucose/química , Glucose/metabolismo , Transporte de Elétrons , Biocatálise , AdsorçãoRESUMO
BACKGROUND OBJECTIVE: This study aimed to understand the basic situation of adults with human immunodeficiency virus (HIV) receiving antiretroviral therapy (ART) in Meigu County, Liangshan Yi Autonomous Prefecture. The information of patients who had been on ART for more than 6 months, the effect of ART, the possible reasons for ART failure, knowledge of drug resistance among patients with ART failure and the possible reasons for the emergence of drug resistance were analyzed. METHODS: A total of 2753 people living with HIV (PLWH) were collected for HIV-1 RNA virus nucleic acid testing. Plasma specimens with HIV-1 RNA ≥ 1000 copies/mL were sent to the laboratory for nucleic acid extraction, PCR, electrophoresis and sequencing, and the sequencing results were submitted to the HIV drug resistance database of Stanford University for subtyping to determine the drug resistance mutation sites and drug sensitivity levels. RESULTS: A total of 2753 patients were enrolled in this study. Antiviral therapy failed in 288 patients and was successfully amplified in 245, of which 111 had resistance genes. The resistance rate to failure of viral suppression was 45.3% (111/245). The highest rates of resistance to NNRTIs were found for efavirenz (EFV) and nevirapine (NVP) (42.9%), and the highest rates of resistance to NRTIs were found for 3TC and emtricitabine (FTC) (15.9%). The most common NNRTI resistance mutation site was K103N (20.8%), followed by V179D (9.4%) and V106M (7.8%); the most common NRTI resistance mutation site was M184V/I/MV (14.3%), followed by K65R (6.9%); three PI-associated resistance mutation sites were identified. The subtype of the resistant strain was CRF07-BC in almost all patients (98.9%). CONCLUSIONS: Compared with the previous low ART efficacy in the county, this study showed that the overall virological failure (VF) resistance rate in the county is still low, dominated by resistance to EFV, NVP, 3TC, FTC, and didanosine (DDI). Due to economic constraints, the core regimen is still 3TC + TDF, but before initiating ART, testing for HIV-1 subtypes and resistance should be conducted to avoid resistance that can lead to VF, especially for patients with high risk factors for resistance as shown by epidemiologic investigations.
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Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Ácidos Nucleicos , Adulto , Humanos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Emtricitabina/uso terapêutico , HIV-1/genética , Nevirapina/farmacologia , Nevirapina/uso terapêutico , Didanosina , Mutação , Resistência a Medicamentos , Farmacorresistência Viral/genéticaRESUMO
OBJECTIVE: To evaluate vaccine effectiveness (VE) of a live oral pentavalent rotavirus vaccine (RotaTeq, RV5) among young children in Shanghai, China, via a test-negative design study. STUDY DESIGN: We consecutively recruited children visiting a tertiary children's hospital for acute diarrhea from November 2021 to February 2022. Information on clinical data and rotavirus vaccination was collected. Fresh fecal samples were obtained for rotavirus detection and genotyping. To evaluate VE of RV5 against rotavirus gastroenteritis among young children, unconditional logistic regression models were conducted to compare ORs for vaccination between rotavirus-positive cases and test-negative controls. RESULTS: A total of 390 eligible children with acute diarrhea were enrolled, including 45 (11.54%) rotavirus-positive cases and 345 (88.46%) test-negative controls. After excluding 4 cases (8.89%) and 55 controls (15.94%) who had received the Lanzhou lamb rotavirus vaccine, 41 cases (12.39%) and 290 controls (87.61%) were included for the evaluation of RV5 VE. After adjustment for potential confounders, the 3-dose RV5 vaccination showed 85% (95% CI, 50%-95%) VE against mild to moderate rotavirus gastroenteritis among children aged 14 weeks to ≤4 years and 97% (95% CI, 83%-100%) VE among children aged 14 weeks to ≤2 years with genotypes G8P8, G9P8, and G2P4 represented 78.95%, 18.42%, and 2.63% of circulation strains, respectively. CONCLUSIONS: A 3-dose vaccination of RV5 is highly protective against rotavirus gastroenteritis among young children in Shanghai. The G8P8 genotype prevailled in Shanghai after RV5 introduction.
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Gastroenterite , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Vacinas contra Rotavirus/uso terapêutico , Gastroenterite/epidemiologia , Gastroenterite/prevenção & controle , Vacinas Combinadas , China/epidemiologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Diarreia/epidemiologia , Diarreia/prevenção & controle , Vacinação , HospitalizaçãoRESUMO
We analyze from a theoretical perspective recent experiments where chiral discrimination in biological systems was established using Atomic Force Microscopy (AFM). Even though intermolecular forces involved in AFM measurements have different origins, i.e., electrostatic, bonding, exchange, and multipole interactions, the key molecular forces involved in enantiospecific biorecognition are electronic spin exchange and van der Waals (vdW) dispersion forces, which are sensitive to spin-orbit interaction (SOI) and space-inversion symmetry breaking in chiral molecules. The vdW contribution to chiral discrimination emerges from the inclusion of SOI and spin fluctuations due to the chiral-induced selectivity effect, a result we have recently demonstrated theoretically. Considering these two enantiospecific contributions, we show that the AFM results regarding chiral recognition can be understood in terms of a simple physical model that describes the different adhesion forces associated with different electron spin polarization generated in the (DD), (LL), and (DL) enantiomeric pairs, as arising from the spin part of the exchange and vdW contributions. The model can successfully produce physically reasonable parameters accounting for the vdW and exchange interaction strength, accounting for the chiral discrimination effect. This fact has profound implications in biorecognition where the relevant intermolecular interactions in the intermediate-distance regime are clearly connected to vdW forces.
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Herein we describe the self-assembly of an achiral molecule into macroscopic helicity as well as the emergent chiral-selective spin-filtering effect. It was found that a benzene-1,3,5-tricarboxamide (BTA) motif with an aminopyridine group in each arm could coordinate with AgI and self-assemble into nanospheres. Upon sonication, symmetry breaking occurred and the nanospheres transferred into helical nanofibers with strong CD signals. Although the sign of the CD signals appeared randomly, it could be controlled by using the as-made chiral assemblies as a seed. Furthermore, it was found that the charge transport of the helical nanofibers was highly selective with a spin-polarization transport of up to 45 %, although the chiral nanofibers are composed exclusively from achiral building blocks. This work demonstrates symmetry breaking under sonication and the chiral-selective spin-filtering effect.
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We report on the synthesis and self-assembly of 2,15- and 4,13-disubstituted carbo[6]helicenes 1 and 2 bearing 3,4,5-tridodecyloxybenzamide groups. The self-assembly of these [6]helicenes is strongly influenced by the substitution pattern in the helicene core that affects the mutual orientation of the monomeric units in the aggregated form. Thus, the 2,15-substituted derivative 1 undergoes an isodesmic supramolecular polymerization forming globular nanoparticles that maintain circularly polarized light (CPL) with glum values as high as 2 × 10-2. Unlike carbo[6]helicene 1, the 4,13-substituted derivative 2 follows a cooperative mechanism generating helical one-dimensional fibers. As a result of this helical organization, [6]helicene 2 exhibits a unique modification in its ECD spectral pattern showing sign inversion at low energy, accompanied by a sign change of the CPL with glum values of 1.2 × 10-3, thus unveiling an example of CPL inversion upon supramolecular polymerization. These helical supramolecular structures with high chiroptical activity, when deposited on conductive surfaces, revealed highly efficient electron-spin filtering abilities, with electron spin polarizations up to 80% for 1 and 60% for 2, as measured by magnetic conducting atomic force microscopy.
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Squaraine dyes are well known for their strong absorption in the visible regime. Reports on chiral squaraine dyes are, however, scarce. To address this gap, we here report two novel chiral squaraine dyes and their achiral counterparts. The presented dyes are aggregated in solution and in thin films. A detailed chiroptical study shows that thin films formed by co-assembling the chiral dye with its achiral counterpart exhibit exceptional photophysical properties. The circular dichroism (CD) of the co-assembled structures reaches a maximum when just 25 % of the chiral dye are present in the mixture. The solid structures with the highest relative CD effect are achieved when the chiral dye is used solely as a director, rather than the structural component. The chiroptical data are further supported by selected spin-filtering measurements using mc-AFM. These findings provide a promising platform for investigating the relationship between the dissymmetry of a supramolecular structure and emerging material properties rather than a comparison between a chiral molecular structure and an achiral counterpart.
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Studying the self-assembly behavior of DNA origami allows a better understanding of molecular assembly characteristics at the nanoscale. Presently, the mechanisms governing growth and dynamics of DNA origami assembly are still not very clear and there is a lack of direct visualization of the growth processes on the long single-strand scaffold. Here, we investigate the kinetics, especially the real-time seeding growth process of six special designs of 2D DNA origami at room temperature (RT) without the assistance of denaturing chemicals. The prealignment of single-strand long scaffold and logical seeding growth behaviors are revealed during the growth process at RT. Furthermore, we studied the thermal stability of the DNA nanostructures under limited structural defects. Revealed characteristics of seeding growth can be used to build large and complex DNA nanodevices capable of performing logical operations with nanometer precision.
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DNA/química , Nanoestruturas/química , Temperatura , Conformação de Ácido Nucleico , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Influenza A/H3N2 viruses are associated with severe epidemics. Antiviral resistance and continued antigenic drift are the major concerns regarding prophylaxis and treatment of influenza. The objectives of this study were to investigate the prevalence and frequency of antiviral drug resistance in influenza A/H3N2 viruses circulating among Shanghainese children from June 2009 to May 2012 and to understand the genetic evolution of the hemagglutinin (HA) epitopes. Nasopharyngeal/throat swabs were collected from outpatients with influenza-like illness. Of the 3,475 children tested, 344 (9.9%) were positive for influenza A/H3N2 viruses. Epidemics of influenza A/H3N2 occurred in July-September 2009, August 2010-January 2011, and November 2011-May 2012. The 71 A/H3N2-positive specimens were sequenced to characterize the genotypic antiviral resistance and genetic drift in the HA epitopes. All of the 71 A/H3N2 viruses sequenced were genotypically resistant to adamantine but sensitive to oseltamivir. The HA1 sequence analysis revealed that the A/H3N2 viruses underwent constant mutations in the HA antigenic sites over the three seasons compared with the corresponding vaccine strains, and amino acid changes in at least three epitopes were observed each season. Phylogenic analyses indicated that the A/H3N2 strains circulating in Shanghai fell into clades different from those of the corresponding seasonal vaccine strains and were grouped into the A/Perth/16/2009 genetic clade and the A/Victoria/208/2009 genetic clades 3B, 3C, and 5. The continuous monitoring of genetic drift and antiviral resistance of influenza viruses is important for the management of influenza and for updating the vaccine composition.
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Antivirais/farmacologia , Farmacorresistência Viral , Deriva Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/virologia , Adolescente , Amantadina/análogos & derivados , Amantadina/farmacologia , Criança , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Feminino , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Influenza Humana/epidemiologia , Mutação de Sentido Incorreto , Nasofaringe/virologia , Oseltamivir/farmacologia , Filogenia , Prevalência , RNA Viral/genética , RNA Viral/isolamento & purificação , Análise de Sequência de DNA , Homologia de SequênciaRESUMO
BACKGROUND: The significance of ABCB11 variants have been studied in some cholestatic diseases, but this is not clear in transient neonatal cholestasis (TNC). The aim of the present study was to explore the association between ABCB11 variants and TNC. METHODS: This was a case-control study. A total of 192 children with TNC referred to a tertiary referral hospital in eastern China were enrolled as subjects, and 196 healthy children were selected as controls. Part of the promoter and exons of the ABCB11 gene were sequenced directly. The single nucleotide polymorphism (SNP) site of V444A was tested using fluorescent quantitative polymerase chain reaction. Potential consequences of variants were predicted using bioinformatics software. The biochemistry indices were compared between the patients with or without possibly pathogenic variants/mutations. RESULTS: Twenty-eight variants, including 14 novel ones, were detected. Four novel, possibly pathogenic mutations (I416I, K436N, R928Q and IVS7+5G>A) were detected in six subjects. The γ-glutamyltransferase level of these six was lower than in the others (P = 0.054). The genotype distribution of the four common SNP sites, V444A, A535A, A865V and A1082A, was not significantly different between TNC patients and controls. CONCLUSIONS: Approximately 3% of TNC cases can be attributed to ABCB11 mutations.
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Transportadores de Cassetes de Ligação de ATP/genética , Colestase Intra-Hepática/genética , DNA/genética , Predisposição Genética para Doença , Mutação , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Colestase Intra-Hepática/patologia , Éxons , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase , Estudos RetrospectivosRESUMO
OBJECTIVE: To investigate the plasma amino acid spectrum in infants more than 1-year-old with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) in order to identify potential diagnostic markers of NICCD. METHODS: Infants less than 1 year of age who had been referred to our hospital for investigation of suspected conjugated hyperbilirubinemia between June 2003 and June 2009 were eligible for enrollment. A total of 182 infants were enrolled and divided into three groups: infants diagnosed with NICCD (n = 24), according to gene testing and/or western blotting results; infants diagnosed with biliary atresia (BA; n = 20), according to intra-operative cholangiography findings; and infants diagnosed with idiopathic neonatal intrahepatic hepatitis (INH; n = 138), according to exclusionary findings for diseases affecting the extrahepatic biliary system and no positive serology results to indicate infections with hepatitis B, C, A or E, toxoplasmosis, rubella, herpes simplex, human immunodeficiency virus-1, or syphilis. The plasma amino acid spectrum of each infant was analyzed by tandem mass spectrometry (MS/MS). The concentrations of 18 amino acids, as well as the ratio of each amino acid to total amino acids, were compared among the three groups. Selected ratios of amino acids were analyzed by receiver operating characteristic (ROC) curve analysis. RESULTS: Compared with the BA and INH groups, the NICCD group had significantly lower levels of alanine (Ala; 175.7 and 205.7 vs. 136.3 mumol/L, P = 0.0001), aspartic acid (Asp; 47.5 and 43.1 vs. 31.55 mumol/L, P = 0.0041), glutamic acid (Glu; 276.16 and 263.24 vs. 175.71 mumol/L, P = 0.0075) and tryptophan (Trp; 41.90 and 47.97 vs. 28.51 mumol/L, P = 0.0003), but significantly higher levels of methionine (Met; 28.24 and 29.35 vs. 71.40 mumol/L, P = 0.0390), tyrosine (Tyr; 55.8 and 57.02 vs. 116.81 mumol/L, P = 0.0072) and citrulline (Cit; 15.09 and 15.65 vs. 97.42 mumol/L, P = 0.0001). The ratio of each amino acid to total amino acids showed the same trends for the NICCD group. The calculated areas under the ROC curves of the ratios of Cit, Tyr, and Met to the total amino acids were 0.874 (95% CI: 0.752 - 0.996), 0.814 (95% CI: 0.706 - 0.923), and 0.705 (95% CI: 0.535 - 0.875) respectively. The calculated area under the ROC curve of the ratio of Cit to Ala was 0.893 (95% CI: 0.781 - 1.005), and when the cut-off value of the ratio of Cit to Ala was 0.14 for diagnosis of NICCD, the sensitivity and specificity were 75% and 95% respectively. CONCLUSION: The plasma amino acid spectrum may represent a diagnostic indicator for NICCD, particularly the ratio of Cit to Ala.
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Aminoácidos/sangue , Citrulinemia/sangue , Feminino , Humanos , Lactente , Masculino , Espectrometria de Massas em TandemRESUMO
The chirality-induced spin selectivity (CISS) effect allows thin-film layers of chiral conjugated molecules to function as spin filters at ambient temperature. Through solvent-modulated dropcasting of chiral l- and d-perylene diimide (PDI) monomeric building blocks, two types of aggregate morphologies, nanofibers and nanodonuts, may be realized. Spin-diode behavior is evidenced in the nanodonut structures. Stacked PDI units, which form the conjugated core of these nanostructures, dominate the nanodonut-Au electrode contact; in contrast, the AFM tip contacts largely the high-resistance solubilizing alkyl chains of the chiral monomers that form these nanodonuts. Current-voltage responses of the nanodonuts, measured by magnetic conductive AFM (mC-AFM), demonstrate substantial spin polarizations as well as spin current rectification ratios (>10) that exceed the magnitudes of those determined to date for other chiral nanoscale systems. These results underscore the potential for chiral nanostructures, featuring asymmetric molecular junctions, to enable CISS-based nanoscale spin current rectifiers.
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A prospective investigation was carried out among pediatric outpatients and inpatients with acute non-dysenteric diarrhea between August, 2008 and July, 2009 in Shanghai, Hangzhou, Chongqing, and Tianjin, China. One step real-time RT-PCR was used for detection of norovirus (NoV) genogroups I and II (GI, GII). The NoV genotypes were classified based on partial capsid sequences. Rotavirus (RV) was detected in parallel. Among 4,123 fecal samples from outpatients, 1,067 (25.9%) were NoV-positive, of which 1,051 (98.5%) belonged to GII and 1,309 (31.7%) were RV-positive. In the inpatient group (n = 317), 25.6% were NoV-positive and 41.6% were RV-positive. Four hundred and fifty-one out of 1,067 NoV-positive strains were sequenced and genotyped and 6 typed strains were GI (3 GI.3, 2 GI.5, 1 GI.4) and 445 typed strains were GII. GII strains clustered into nine genotypes including GII.4 2006b (69.2%), the only GII.4 variant identified in this study, followed by GII.3 (23.8%), GII.6 (3.6%), GII.12 (1.3%), GII.2 (0.9%), GII.13 (0.4%), GII.14 (0.2%), GII.7 (0.2%), and GII.16 (0.2%). A peak of NoV infections was observed during the cold season in Tianjin, while NoV activity was higher between late summer and autumn and lower during winter in Shanghai, Hangzhou, and Chongqing. NoV is a common causative agent of childhood diarrhea in China and the seasons of NoV-associated diarrhea varies between regions. The results show that NoV GII.4 2006b was the predominant strain circulating in China between 2008 and 2009.
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Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/classificação , Norovirus/isolamento & purificação , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Feminino , Genótipo , Humanos , Lactente , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Norovirus/genética , Prevalência , Estudos Prospectivos , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNARESUMO
[This corrects the article DOI: 10.3389/fonc.2022.855945.].
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Background: Routine vaccination of infants for protecting against hepatitis B virus (HBV) infection and its serious consequences, including hepatocellular cancer (HCC), has been carried out in Shanghai, China, since 1986. We therefore have examined the trend of HBV infection and HCC incidences before and after HBV vaccination over decades to assess the potential influences of the Shanghai HBV vaccination program. Methods: Data on incidences of HBV infection and HCC were collected from the Shanghai Cancer Registry and the Shanghai HBV vaccination follow-up study. Joint-point regression and the Bayesian age-period-cohort statistical analysis methods were used. Results: The incidences of HBV infection dramatically declined from 23.09 and 1.13 per 100,000 for males and females in 2000 to 3.24 (-85.97%) and 0.22 (-80.53%) per 100,000 in 2014, respectively. Sero-epidemiological data from the sampling surveys during 20 years of follow-up showed that less than 1% of people undergoing HBV vaccination have a positive serum HBsAg. Consistently, the annual adjusted standardization rates (ASR) of HCC steadily fell from 33.38 and 11.65 per 100,000 for males and females in 1973 to 17.34 (-49.2%) and 5.60 (-51.9%) per 100,000 in 2014, respectively. The annual percentage change in overall HCC incidences is about -2%. HCC incidences in males at younger age groups (age <50 years old), particularly in those with age <34 groups, showed an accelerating decrease over time, whereas HCC incidences significantly declined in the female population across all age groups except for those under 19 years of age. The results supported that the universal HBV vaccination in newborns is easy to implement with high coverages and is effective for preventing both HBV infection and HCC in populations.
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OBJECTIVES: This study aimed to understand the epidemiological and clinical characteristics of pediatric SARS-CoV-2 infection during the early stage of Omicron variant outbreak in Shanghai. METHODS: This study included local COVID-19 cases <18 years in Shanghai referred to the exclusively designated hospital from March 7 to March 31, 2022. Clinical data, epidemiological exposure, and COVID-19 vaccination status were collected. Relative risks (RRs) were calculated to assess the effect of vaccination on symptomatic infection and febrile disease. RESULTS: A total of 376 pediatric cases of COVID-19 (median age: 6.0 ± 4.2 years) were referred to the designated hospital, including 257 (68.4%) symptomatic cases and 119 (31.6%) asymptomatic cases. Of the 307 (81.6%) children ≥3 years eligible for COVID-19 vaccination, 110 (35.8%) received two doses of vaccines. The median interval between the completion of two-dose vaccination and infection was 3.5 (interquartile range [IQR]: 3, 4.5) months. Compared with no vaccination, two-dose COVID-19 vaccination reduced the risks of symptomatic infection and febrile disease by 35% (RR 0.65, 95% confidence interval [CI]: 0.53-0.79) and 33% (RR 0.64, 95% CI: 0.51-0.81) among confirmed cases. Eighty-four percent of symptomatic cases had fever (mean duration: 1.7 ± 1.0.8 days), 40.5% had cough, and 16.4% had transient leukopenia. Three hundred and seven (81.6%) had an epidemiological exposure in household (69.1%), school (21.8%), and residential area (8.8%). CONCLUSION: The surge of pediatric COVID-19 cases and multiple transmission model reflect wide dissemination of Omicron variant in the community. Asymptomatic infection is common among Omicron-infected children. COVID-19 vaccination can offer some protection against symptomatic infection and febrile disease.
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COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Criança , Pré-Escolar , China/epidemiologia , Surtos de Doenças/prevenção & controle , Humanos , Lactente , SARS-CoV-2RESUMO
The impacts of the influent type in wastewater treatment plants (WWTPs) on the distribution patterns of the microbial community and functional characteristics were investigated. The obtained results indicated that the influent types exhibited evident influences on the microbial distribution patterns. The diversity and richness of functional microbes in HI-WWTP (with a ratio of >30% industrial wastewater in influents) were evidently decreased compared with those in HM- (with 70-90% municipal wastewater in influents) and M-WWTPs (with >90% municipal wastewater in influents). The core functional bacteria included denitrifiers, anaerobic fermentation bacteria (AFB), organic degrading bacteria (ODB), phosphorus accumulating organisms (PAO) and nitrite oxidizing bacteria (NOB), but they exhibited distinct abundances in WWTPs receiving different categories of wastewater. The denitrifiers in HI-WWTPs was 15.6-32.5% higher than that in other WWTPs, while PAOs had higher abundances in M - and HI-WWTPs (28.9% and 39.3%, respectively) compared with HM-WWTPs. Clear co-occurrence relationships were found among the main functional microbes with similar metabolic characteristics. Moreover, information on functional genes related to carbon, nitrogen and phosphorus metabolism, which is closely associated with pollutant removal efficiency, was obtained. M-WWTPs had higher abundances of genetic expressions for organic matters degradation (i.e. amino acid (10.42%) and carbohydrate (9.86%) metabolisms). Nar, Nir and Nor showed lowest abundances in HM-WWTPs, causing the low nitrogen removal (63.04-65.79%). However, influent type had little effect on genetic expression related with phosphorus removal. This work provided new insights into the interrelationship among bacterial co-occurrence, microbial activity and pollutant removal in WWTPs with different influent types.
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Microbiota , Purificação da Água , Nitrogênio , Fósforo , Esgotos , Eliminação de Resíduos Líquidos , Águas ResiduáriasRESUMO
It is established that electron transmission through chiral molecules depends on the electron's spin. This phenomenon, termed the chiral-induced spin selectivity (CISS), effect has been observed in chiral molecules, supramolecular structures, polymers, and metal-organic films. Which spin is preferred in the transmission depends on the handedness of the system and the tunneling direction of the electrons. Molecular motors based on overcrowded alkenes show multiple inversions of helical chirality under light irradiation and thermal relaxation. The authors found here multistate switching of spin selectivity in electron transfer through first generation molecular motors based on the four accessible distinct helical configurations, measured by magnetic-conductive atomic force microscopy. It is shown that the helical state dictates the molecular organization on the surface. The efficient spin polarization observed in the photostationary state of the right-handed motor coupled with the modulation of spin selectivity through the controlled sequence of helical states, opens opportunities to tune spin selectivity on-demand with high spatio-temporal precision. An energetic analysis correlates the spin injection barrier with the extent of spin polarization.