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1.
Chemosphere ; 341: 140053, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690558

RESUMO

The catalytic efficiency of photocatalysts highly depends on electron transport and mass transfer. Herein, we designed and prepared an effective H2WO4/Ti3C2/g-C3N4 (HTC) Z-scheme heterojunction through interfacial engineering strategy. The results manifested that 97.4% of Cr(VI) (80 µM, 50 mL) could be removed by HTC heterojunction within 10 min under visible light irradiation. The reduction rate constant of Cr(VI) for H2WO4/g-C3N4 (HC) heterojunction increased by a factor of 21 after introducing the conductive Ti3C2. Moreover, 96% of tetracycline (TC, 10 mg L-1, 50 mL) could be degraded by HTC heterojunction within 30 min. The electronic conductivity and ionic diffusion coefficient of HC heterojunction increased by a factor of 64 and 1064 after adding Ti3C2, respectively. This result indicated that the introduction of highly conductive Ti3C2 significantly improved the electron and mass transfer of the heterojunction. Meanwhile, the HCT heterojunction displayed favorable photocurrent, and keep excellent photostability during the long-term test. Moreover, density functional theory (DFT) calculations demonstrated that the internal electric field (IEF) from g-C3N4 to H2WO4 in HCT heterojunction promotes the combination of the photoinduced electrons in the H2WO4 conduction band (CB) with photoinduced holes in the g-C3N4 valence band (VB), thus accelerating the charge transfer in the HCT Z-scheme heterojunction. The antibacterial efficiency of HTC heterojunction against E. coli and S. aureus could reach up to 98.4% and 99.7%, respectively. The degradation intermediates and the potential degradation mechanism of TC were analyzed and proposed based on the results of HPLC-MS analysis. Moreover, the toxicity of TC and degradation intermediates were estimated by Toxicity Estimation Software (T.E.S.T.) based on quantitative structure-activity relationship (QSAR). This work provided a valuable guideline for designing the effective MXene-based Z-scheme heterojunction for environmental remediation.


Assuntos
Elétrons , Recuperação e Remediação Ambiental , Escherichia coli , Staphylococcus aureus , Titânio , Antibacterianos
2.
FASEB J ; 37(6): e22995, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37219526

RESUMO

Immuno-oncology (IO)-based therapies such as checkpoint inhibitors, bi-specific antibodies, and CAR-T-cell therapies have shown significant success in the treatment of several cancer indications. However, these therapies can result in the development of severe adverse events, including cytokine release syndrome (CRS). Currently, there is a paucity of in vivo models that can evaluate dose-response relationships for both tumor control and CRS-related safety issues. We tested an in vivo PBMC humanized mouse model to assess both treatment efficacy against specific tumors and the concurrent cytokine release profiles for individual human donors after treatment with a CD19xCD3 bispecific T-cell engager (BiTE). Using this model, we evaluated tumor burden, T-cell activation, and cytokine release in response to bispecific T-cell-engaging antibody in humanized mice generated with different PBMC donors. The results show that PBMC engrafted NOD-scid Il2rgnull mice lacking expression of mouse MHC class I and II (NSG-MHC-DKO mice) and implanted with a tumor xenograft predict both efficacy for tumor control by CD19xCD3 BiTE and stimulated cytokine release. Moreover, our findings indicate that this PBMC-engrafted model captures variability among donors for tumor control and cytokine release following treatment. Tumor control and cytokine release were reproducible for the same PBMC donor in separate experiments. The PBMC humanized mouse model described here is a sensitive and reproducible platform that identifies specific patient/cancer/therapy combinations for treatment efficacy and development of complications.


Assuntos
Leucócitos Mononucleares , Linfócitos T , Humanos , Animais , Camundongos , Camundongos Endogâmicos NOD , Resultado do Tratamento , Síndrome da Liberação de Citocina , Citocinas , Modelos Animais de Doenças , Camundongos Knockout , Camundongos SCID
3.
J Hazard Mater ; 451: 131149, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36924745

RESUMO

Selectively regulating active factors in photocatalytic reactions by designing materials is one of the very important factors. Herein, we prepared spindle-like core-shell Ag@NH2-MIL-88B composites (Ag@NM-88) by a two-step hydrothermal method. The as-prepared Ag@NM-88 displayed superior photocatalytic activity for Cr(VI) reduction under LED light, compared with the activities of pure NH2-MIL-88B (NM-88) and Ag/NM-88 (Ag was deposited on NH2-MIL-88B). The core-shell structure Ag@NM-88 was not only beneficial to the absorption of light but also beneficial to the separation of photogenerated e- and h+. More importantly, it was further confirmed by active radical capture experiments and nitroblue tetrazolium (NBT) conversion experiments that the design of the core-shell structure could effectively prevent photogenerated e- from combing with O2 to form •O2-, so that photogenerated e- directly reduced Cr(VI), thereby improving the reaction rate. In addition, it could still maintain good stability after 5 cycles, indicating that the construction of a core-shell structure is also conducive to improving stability. This work provides a strategy for selectively regulating the active components of photocatalysts, and provides new insights into the relationship between interfacial charge transfer and molecular oxygen activation in photocatalytic reduction Cr(VI) systems.

4.
J Colloid Interface Sci ; 640: 132-143, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842419

RESUMO

Developing highly efficient and stable photocatalysts remains a major challenge for the remediation of environmental pollutants. In this work, the Bi0 decorated BiOI-Bi2O3/C3N4 heterojunction (Bi@BiOI-Bi2O3/C3N4) film was fabricated through ultrasonic stripping, I- etching and in situ UV-reduction processes and then characterized thoroughly by various analytical techniques. The characteristics of simultaneous mitigation of phenol and Cr(VI) were evaluated over Bi@BiOI-Bi2O3/C3N4 photoanode under visible light. The results exhibited that both phenol and Cr(VI) were removed completely by the photoanode at 2.5 V within 1.5 h, superior to our previous report. The synergy of the surface plasmon resonance (SPR) effect of Bi0 and ternary heterojunction accelerated the separation and transfer of photo-induced charge carrier and thus heavily promoted the removal efficiency. Moreover, the excellent stability of this photoanode was hold with no considerably activity attenuation after 4 cycles. Finally, a dual Z-scheme charge transfer process was presented. This work offers an attractive pathway to construct highly active photoelectrode with promising application for simultaneous remediation of organics and heavy metals in wastewater.

5.
Front Immunol ; 13: 1007257, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238277

RESUMO

Objective: To investigate the distribution and clinical significance of the rods and rings (RR) pattern in various diseases. Methods: A total of 169,891 patients in Peking Union Medical College Hospital (PUMCH) and 29,458 patients in Inner Mongolia People's Hospital (IMPH) from January 2018 to December 2020 were included, and the results of ANA (antinuclear antibodies) and special antibodies were analyzed retrospectively. Results: The positive rates of ANA and RR patterns were 34.84%, 0.16% in PUMCH, and 44.73%, 0.23% in IMPH. Anti-RR antibodies mainly appear in adults (≥ 41 years), mostly of low or medium fluorescence titers. Isolated RR patterns were mostly presented (60.30% and 69.12%, respectively), and the RR pattern mixed with the speckled pattern was most commonly observed among patients having two or more patterns. The RR pattern existed in a variety of diseases including hepatitis C, AIDs, pulmonary diseases, nephropathy diseases, and even healthy people. The highest prevalence of the RR pattern was observed in hepatic diseases, such as hepatic dysfunction (0.79%), hepatic cirrhosis (1.05%), PBC (0.85%), and AIH (0.65%), etc. The positive rate of specific antibodies in RR pattern cases was 31.25%, and anti-Ro52 (27, 20.61%) was the most common target antibody. Conclusion: The RR pattern had a low prevalence in ANAs test samples and varied in different nationalities and regions. Except for hepatitis C, it could be observed in AIDs, pulmonary diseases, nephropathy, other hepatic diseases, and even healthy people, but the positive rate was slightly higher in hepatic diseases. Its mechanism of action and clinical relevance still need clarification.


Assuntos
Síndrome da Imunodeficiência Adquirida , Hepatite C , Hepatopatias , Pneumopatias , Adulto , Anticorpos Antinucleares , China/epidemiologia , Técnica Indireta de Fluorescência para Anticorpo , Hepacivirus , Humanos , Estudos Retrospectivos
6.
Front Immunol ; 13: 912961, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059513

RESUMO

Background/aims: Primary sclerosing cholangitis (PSC) is a chronic inflammatory biliary disease for which the immunopathological basis remains an enigma. Natural killer (NK) cells are key components of innate immunity and seemingly play diversified roles in different autoimmune disorders (AIDs). The aim of this study was to determine the role of NK cells in the pathogenesis of PSC. Methods: The frequency and phenotype of circulating NK cells in a large cohort of patients with PSC and healthy controls (HCs) were systematically examined. In addition, the functional capacity of NK cells including cytotoxicity and cytokine production was studied. Results: The frequency of CD3-CD56dimCD16+ (defined as CD56dim) NK cells in PSC patients was significantly lower in comparison to HCs. CD56dim NK cells from PSC displayed a more immature phenotype including high expression of the natural killing receptor NKp46 and downregulation of the highly differentiated NK cell marker CD57. Interestingly, the reduction of CD57 expression of NK cells was associated with the disease severity of PSC. In addition, PSC CD56dim NK cells exhibited increased CD107a degranulation and cytolytic activity toward target cells compared with HCs. Further analysis demonstrated that CD57-CD56dim NK cells from PSC had elevated expression of NKp46, NKp30, IL-2 receptor, and KLRG1 and higher cytotoxic capacity as compared to CD57+CD56dim NK cells. Conclusions: Our data demonstrate that the differentiation of PSC NK cells is dysregulated with enhanced cytotoxic activity. This change is likely to be functionally involved in pathogenesis and disease progression, deducing the potential of NK-directed immunotherapy for PSC.


Assuntos
Colangite Esclerosante , Estudos de Coortes , Humanos , Células Matadoras Naturais
7.
Microbiol Spectr ; 10(5): e0231522, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36102524

RESUMO

Six highly pathogenic avian influenza (HPAI) H5N1 viruses (clade 2.3.4.4b) were detected in migratory birds in Hubei Province in November 2021. Phylogenetic analysis indicated that the viruses in the study included two different reassortants between H5N1 viruses that were circulating in Eurasia and low-pathogenic avian influenza viruses (LPAIVs). Several amino acid substitutions that contributed to the enhanced replication or virulence in mammals were observed in these viruses, suggesting a potential threat of the H5N1 viruses to human health. IMPORTANCE Here, we obtained the whole-genomes of six H5N1 viruses from dead or rescued wild birds in Hubei Province. These viruses were divided into two genotypes and had different evolutionary trajectories from previously reported H5N1 viruses in China. Extensive reassortment events between high-pathogenic (HP) and low-pathogenic (LP) avian influenza viruses (AIVs) were observed in these viruses. Moreover, a key amino acid analysis also suggests a potential threat of H5N1 viruses to public health. Our work explored the prevalent patterns of H5N1 viruses in wild birds and replenished the viral population data of H5N1 viruses in central China.


Assuntos
Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Aviária , Animais , Humanos , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/epidemiologia , Filogenia , Vírus da Influenza A/genética , Aves , Animais Selvagens , Mamíferos , China/epidemiologia , Aminoácidos
8.
Microbiol Spectr ; 10(4): e0165222, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35862978

RESUMO

Active surveillance of avian influenza virus (AIV) in wetlands and lakes is important for exploring the gene pool in wild birds. Through active surveillance from 2015 through 2019, 10,900 samples from wild birds in central China were collected, and 89 AIVs were isolated, including 2 subtypes of highly pathogenic AIV and 12 of low-pathogenic AIV; H9N2 and H6Ny were the dominant subtypes. Phylogenetic analysis of the isolates demonstrated that extensive intersubtype reassortments and frequent intercontinental gene exchange occurred in AIVs. AIV gene segments persistently circulated in several migration seasons, but interseasonal persistence of the whole genome was rare. The whole genomes of one H6N6 and polymerase basic 2 (PB2), polymerase acidic (PA), hemagglutinin (HA), neuraminidase (NA), M, and nonstructural (NS) genes of one H9N2 virus were found to be of poultry origin, suggesting a spillover of AIVs from poultry to wild birds. Importantly, one H9N2 virus only bound to human-type receptor, and one H1N1, four H6, and seven H9N2 viruses possessed dual receptor-binding capacity. Nineteen of 20 representative viruses tested could replicate in the lungs of mice without preadaptation, which poses a clear threat of infection in humans. Together, our study highlights the need for intensive AIV surveillance. IMPORTANCE Influenza virus surveillance in wild birds plays an important role in the early recognition and control of the virus. However, the AIV gene pool in wild birds in central China along the East Asian-Australasian flyway has not been well studied. Here, we conducted a 5-year AIV active surveillance in this region. Our data revealed the long-term circulation and prevalence of AIVs in wild birds in central China, and we observed that intercontinental gene exchange of AIVs is more frequent and continuous than previously thought. Spillover events from poultry to wild bird were observed in H6 and H9 viruses. In addition, in 20 representative viruses, 12 viruses could bind human-type receptors, and 19 viruses could replicate in mice without preadaption. Our work highlights the potential threat of wild bird AIVs to public health.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Animais , Animais Selvagens , Aves , Humanos , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Camundongos , Filogenia , Aves Domésticas
9.
Hepatology ; 75(2): 266-279, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34608663

RESUMO

BACKGROUND AND AIMS: The increased frequency of urinary tract infections in patients with primary biliary cholangitis (PBC) and the cross-reactivity between the lipoyl domains (LD) of human pyruvate dehydrogenase complex (hPDC-E2) and Escherichia coli PDC-E2 (ePDC-E2) have long suggested a role of E. coli in causality of PBC. This issue, however, has remained speculative. We hypothesized that by generating specific constructs of human and E. coli PDC-E2, we would be able to assess the specificity of autoantibody responses and define whether exposure to E. coli in susceptible hosts is the basis for the antimitochondrial antibody (AMA) response. APPROACH AND RESULTS: Importantly, the reactivity of hPDC-E2 LD (hPDC-E2LD) affinity-purified antibodies against hPDC-E2LD could only be removed by prior absorption with hPDC-E2LD and not ePDC-E2, suggesting the presence of unique human PDC-E2 epitopes distinct from E. coli PDC-E2. To identify the autoepitope(s) present in hPDC-E2LD, a more detailed study using a variety of PDC-E2 constructs was tested, including the effect of lipoic acid (LA) on ePDC-E2 conformation and AMA recognition. Individual recombinant ePDCE2 LD domains LD1, LD2 and LD3 did not react with either AMA or antibodies to LA (anti-LA), but in contrast, anti-LA was readily reactive against purified recombinant LD1, LD2, and LD3 expressed in tandem (LP); such reactivity increased when LP was precultured with LA. Moreover, when the three LD (LD1, LD2, LD3) domains were expressed in tandem in pET28a or when LD1 was expressed in another plasmid pGEX, they were lipoylated and reactive to PBC sera. CONCLUSIONS: In conclusion, our data are consistent with an exposure to E. coli that elicits specific antibody to ePDC-E2 resulting in determinant spreading and the classic autoantibody to hPDC-E2LD. We argue this is the first step to development of human PBC.


Assuntos
Autoantígenos/imunologia , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/imunologia , Infecções por Escherichia coli/complicações , Escherichia coli/imunologia , Cirrose Hepática Biliar/microbiologia , Mitocôndrias/imunologia , Proteínas Mitocondriais/imunologia , Autoanticorpos/sangue , Estudos de Casos e Controles , Reações Cruzadas/imunologia , Epitopos/imunologia , Escherichia coli/enzimologia , Hepatite Autoimune/sangue , Humanos , Lipoilação , Conformação Molecular/efeitos dos fármacos , Ácido Tióctico/imunologia , Ácido Tióctico/farmacologia
10.
Emerg Microbes Infect ; 11(1): 73-82, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34825854

RESUMO

Highly pathogenic influenza A(H5N8) viruses have caused several worldwide outbreaks in birds and are able cross the species barrier to infect humans, posing a substantial threat to public health. After the first detection of H5N8 viruses in deceased swans in Inner Mongolia, we performed early warning and active monitoring along swan migration routes in central China. We isolated and sequenced 42 avian influenza viruses, including 40 H5N8 viruses, 1 H5N2 virus, and 1 H9N2 virus, in central China. Our H5N8 viruses isolated in swan stopover sites and wintering grounds showed high nucleotide homologies in the whole genome, revealing a common evolutionary source. Phylogenetic analysis revealed that the H5 viruses of clade 2.3.4.4b prevalent in 2020 have further diverged into two sub-clades: b1 and b2. The phylogeographic analysis also showed that the viruses of sub-clade b2 most likely originated from poultry in Russia. Notably, whooper swans were found to be responsible for the introduction of sub-clade b2 viruses in central China; whooper and tundra swans play a role in viral spread in the Yellow River Basin and the Yangtze River Basin, respectively. Our findings highlight swans as an indicator species for transborder spreading and monitoring of the H5N8 virus.


Assuntos
Anseriformes/virologia , Vírus da Influenza A Subtipo H5N8/isolamento & purificação , Influenza Aviária/epidemiologia , Migração Animal , Animais , Anseriformes/fisiologia , China/epidemiologia , Evolução Molecular , Genoma Viral , Vírus da Influenza A Subtipo H5N2/classificação , Vírus da Influenza A Subtipo H5N2/genética , Vírus da Influenza A Subtipo H5N2/isolamento & purificação , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A Subtipo H9N2/classificação , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Aviária/transmissão , Influenza Aviária/virologia , Filogenia , Filogeografia , Aves Domésticas/virologia , Prevalência , Federação Russa , Sequenciamento Completo do Genoma
11.
Emerg Microbes Infect ; 10(1): 1503-1506, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34260340

RESUMO

Eleven highly pathogenic avian influenza H5N8 viruses (clade 2.3.4.4b) were detected in migratory birds in Central China between November and December 2020, which were highly homologous to strains isolated in Europe from October to December 2020. Phylogenetic analysis indicated that the strains in the study possibly spread from Siberia by migratory birds. In this study, we found H5N8 virus infection in migratory birds could cause severe pathological damage and high viral load in multiple organs.


Assuntos
Vírus da Influenza A Subtipo H5N8/isolamento & purificação , Influenza Aviária/virologia , Migração Animal , Animais , Animais Selvagens/classificação , Animais Selvagens/fisiologia , Animais Selvagens/virologia , Aves/classificação , Aves/fisiologia , Aves/virologia , China , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/fisiopatologia , Filogenia
12.
Sci Bull (Beijing) ; 66(19): 2014-2024, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36654171

RESUMO

Migratory birds are considered natural reservoirs of avian influenza A viruses (AIVs). To further our viral ecology knowledge and understand the subsequent risk posed by wild birds, we conducted a 4-year surveillance study of AIVs in the bird wintering wetlands of the Yangtze River, China. We collected over 8000 samples and isolated 122 AIV strains. Analyses were then carried out with 108 novel sequenced genomes and data were deposited in GISAID and other public databases. The results showed that the Yangtze River wintering wetlands functioned as a mixing ground, where various subtypes of AIVs were detected harboring a high diversity of nucleotide sequences; moreover, a portion of AIV gene segments were persistent inter-seasonally. Phylogenetic incongruence presented complex reassortment events and distinct patterns among various subtypes. In addition, we observed that viral gene segments in wintering wetlands were closely related to known North American isolates, indicating that intercontinental gene flow occurred. Notably, highly pathogenic H5 and low pathogenic H9 viruses, which usually circulate in poultry, were found to have crossed the poultry/wild bird interface, with the viruses introduced to wintering birds. Overall, this study represented the largest AIV surveillance effort of wild birds within the Yangtze River wintering wetlands. Surveillance data highlighted the important role of wintering wild birds in the ecology of AIVs and may enable future early warnings of novel AIV emergence.


Assuntos
Vírus da Influenza A , Influenza Aviária , Animais , Filogenia , Áreas Alagadas , Rios , Influenza Aviária/epidemiologia , Aves , Vírus da Influenza A/genética , Animais Selvagens
13.
J Autoimmun ; 113: 102503, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32546343

RESUMO

Glycosylation of antibodies, particularly in the Fc domain, critically modulate the ability of antibodies to bind to FcRs, maintaining immune quiescence to achieve a finely orchestrated immune response. The removal of sialic acid and galactose residues dramatically alters the physiological function of IgGs, and alterations of Ig glycosylation have been associated with several autoimmune disorders. However, Ig glycosylation has not been extensively studied in autoimmune cholangitis. We applied triple quadruple mass spectroscopy with subsequent multiple reaction monitoring to elucidate the profile, composition and linkage of sugar residues of antibody glycans in patients with primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and healthy controls (HC). Agalactosylated, HexNAc terminated IgG1 glycoforms were enriched in both PBC and PSC. Levels of IgM glycans at site N439 and fucosylated glycans in J chain, were significantly decreased in PBC compared to PSC and HC. PSC patients had decreased bisecting glycoforms and increased biantennary glycoforms on IgA compared to PBC. Importantly, our data demonstrate the association of distinct branching and composition patterns of Ig glycoforms with disease severity and liver cirrhosis, which highlight the importance of glycan biology as a potential mechanism and/or a disease specific signal of inflammation.


Assuntos
Autoanticorpos/metabolismo , Doenças Autoimunes/diagnóstico , Colangite Esclerosante/diagnóstico , Imunoglobulina G/metabolismo , Cirrose Hepática Biliar/diagnóstico , Adulto , Idoso , Autoanticorpos/sangue , Autoanticorpos/imunologia , Doenças Autoimunes/sangue , Doenças Autoimunes/imunologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Casos e Controles , Colangite Esclerosante/sangue , Colangite Esclerosante/imunologia , Feminino , Glicômica/métodos , Glicosilação , Voluntários Saudáveis , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/imunologia , Masculino , Pessoa de Meia-Idade , Polissacarídeos/imunologia , Polissacarídeos/metabolismo , Índice de Gravidade de Doença
14.
Front Microbiol ; 11: 220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117193

RESUMO

In December 2017, an influenza A(H9N2) virus (B51) was isolated from migratory waterfowl in Hubei Province, China. Phylogenetic analysis demonstrated that B51 is a novel reassortant influenza virus containing segments from human H7N4 virus and North American wild bird influenza viruses. This suggest that B51 has undergone multiple reassortment events.

15.
Sci Total Environ ; 715: 136686, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32032984

RESUMO

Recent advances in high-frequency water-quality sensors have enabled direct measurements of physical and chemical attributes in rivers and streams nearly continuously. Water-quality trends can be used to identify important watershed-scale changes driven by natural and anthropogenic influences. Statistical methods to estimate trends using high-frequency data are lacking. To address this gap, an evaluation of the generalized additive model (GAM) approach to test for trends in high-frequency data was conducted. Our proposed framework includes methods for handling serial correlation, trend estimation and slope-change detection, and trend interpretation at arithmetic scale for log-transformed variables. Water-temperature and turbidity data, representing two analytes with different temporal patterns, collected from the James River at Cartersville, Virginia, USA, were chosen for this analysis. Results indicated that the model, including flow, season, time covariates, and interaction between flow and season performed well for both analytes. The same model structure was applied to specific conductance data, collected from a small highly urbanized watershed, with satisfactory model performance. The water temperature GAM results indicated that the significant decreasing-then-increasing patterns after 2012 were mainly driven by air temperature changes. The turbidity trend was not significant over time. The specific conductance results showed a consistently upward trend over the last decade due to ever-increasing urbanization in the small watershed. This study suggests that the GAM method has great potential as a useful tool for trend analysis on high-frequency data, and for informing watershed managers of hydro-climatic and human influences on water quality by detecting crucial signal variation over time.

16.
PeerJ Comput Sci ; 6: e263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33816915

RESUMO

The building of large-scale Digital Elevation Models (DEMs) using various interpolation algorithms is one of the key issues in geographic information science. Different choices of interpolation algorithms may trigger significant differences in interpolation accuracy and computational efficiency, and a proper interpolation algorithm needs to be carefully used based on the specific characteristics of the scene of interpolation. In this paper, we comparatively investigate the performance of parallel Radial Basis Function (RBF)-based, Moving Least Square (MLS)-based, and Shepard's interpolation algorithms for building DEMs by evaluating the influence of terrain type, raw data density, and distribution patterns on the interpolation accuracy and computational efficiency. The drawn conclusions may help select a suitable interpolation algorithm in a specific scene to build large-scale DEMs.

17.
Clin Rev Allergy Immunol ; 58(1): 134-149, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31463807

RESUMO

Cholangiocarcinoma (CCA) is the most common malignancy in patients with primary sclerosing cholangitis (PSC) and carries a high rate of mortality. Although the pathogenesis of CCA in PSC is largely unknown, inflammation-driven carcinogenesis concomitant with various genetic and epigenetic abnormalities are underlying factors. The majority of CCA cases develop from a dominant stricture (DS), which is defined as a stricture with a diameter < 1.5 mm in the common bile duct or < 1.0 mm in the hepatic duct. In PSC patients presenting with an abrupt aggravation of jaundice, pain, fatigue, pruritus, weight loss, or worsening liver biochemistries, CCA should be suspected and evaluated utilizing a variety of diagnostic modalities. However, early recognition of CCA in PSC remains a major challenge. Importantly, 30-50% of CCA in PSC patients are observed within the first year following the diagnosis of PSC followed by an annual incidence ranging from 0.5 to 1.5 per 100 persons, which is nearly 10 to 1000 times higher than that in the general population. Cumulative 5-year, 10-year, and lifetime incidences are 7%, 8-11%, and 9-20%, respectively. When PSC-associated CCA is diagnosed, most tumors are unresectable, and no effective medications are available. Given the poor therapeutic outcome, the surveillance and management of PSC patients who are at an increased risk of developing CCA are of importance. Such patients include older males with large-duct PSC and possibly concurrent ulcerative colitis. Thus, more attention should be paid to patients with these clinical features, in particular within the first year after PSC diagnosis. In contrast, CCA is less frequently observed in pediatric or female PSC patients or in those with small-duct PSC or concurrent Crohn's disease. Recently, new biomarkers such as antibodies to glycoprotein 2 have been found to be associated with an increased risk of developing CCA in PSC. Herein, we review the literature on the pathogenesis, incidence, clinical features, and risk factors, with a focus on various diagnostic modalities of PSC-associated CCA.


Assuntos
Neoplasias dos Ductos Biliares/etiologia , Colangiocarcinoma/etiologia , Colangite Esclerosante/complicações , Algoritmos , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/epidemiologia , Neoplasias dos Ductos Biliares/terapia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/epidemiologia , Colangiocarcinoma/terapia , Colangite Esclerosante/epidemiologia , Colangite Esclerosante/etiologia , Tomada de Decisão Clínica , Gerenciamento Clínico , Suscetibilidade a Doenças , Predisposição Genética para Doença , Humanos , Incidência , Fenótipo , Fatores de Risco
18.
J Autoimmun ; 101: 26-34, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31027870

RESUMO

Primary biliary cholangitis (PBC) is a classic autoimmune disease in which humoral, cytotoxic, and innate immune responses have been implicated with the specific targeting of a mitochondrial antigen. The mainstay of treatment remains the bile acid ursodeoxycholic acid (UDCA). Corticosteroids may have some benefits, but to date, clinical trials of biologics targeting B cells and IL-12/23 have not shown any efficacy. Because activated T cells target the intrahepatic bile ducts in PBC and pre-clinical models suggested that blocking CD80/CD86 with CTLA-4 Ig might have therapeutic benefit in PBC, we performed an open-label trial to determine if CTLA-4 Ig (abatacept) is safe and potentially efficacious in PBC patients with an incomplete response to UDCA. PBC patients with an alkaline phosphatase (ALP) > 1.67 × the upper limit of normal after 6 months on UDCA treatment or who were intolerant of UDCA received abatacept 125 mg s.q. weekly for 24 weeks. The co-primary endpoint was ALP normalization or a >40% reduction from baseline. Among 16 subjects enrolled and who received at least 1 dose of abatacept, 1 (6.3%) met the co-primary endpoint. Absolute and percent changes in ALP [median (95% CI)] were +2.8 U/L (-90.9-96.6) and -0.28% (-21.1-15.5), respectively. No significant changes were observed in ALP, ALT, total bilirubin, albumin, immunoglobulins, or liver stiffness. Abatacept treatment decreased several non-terminally differentiated CD4+ but not CD8+ T cell populations, including decreases in CD4+ CCR5+ (p = 0.02) and CD4+ PD1+ (p = 0.03) lymphocytes. In contrast there were increases in CD4+ CCR7+ lymphocytes (p = 0.034). Treatment emergent adverse events occurred in 4 subjects. Abatacept was well tolerated in this population of PBC patients but like other biologics in PBC was ineffective in achieving biochemical responses associated with improved clinical outcomes.


Assuntos
Produtos Biológicos/uso terapêutico , Cirrose Hepática Biliar/tratamento farmacológico , Abatacepte/administração & dosagem , Abatacepte/efeitos adversos , Abatacepte/uso terapêutico , Adulto , Produtos Biológicos/administração & dosagem , Produtos Biológicos/efeitos adversos , Biomarcadores , Ensaios Clínicos como Assunto , Suscetibilidade a Doenças , Feminino , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Mediadores da Inflamação/metabolismo , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/etiologia , Cirrose Hepática Biliar/metabolismo , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular/efeitos adversos , Terapia de Alvo Molecular/métodos
19.
Clin Rev Allergy Immunol ; 57(1): 83-97, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30564985

RESUMO

Emerging evidence suggests that the increasing prevalence of food allergies is associated with compositional and functional changes in our gut microbiota. Microbiota-host interactions play a key role in regulating the immune system. Development of a healthy gut microbiota and immune system occurs early in life and is largely shaped by exposure to maternal microbes through vaginal/natural delivery and breast milk, whereas use of antibiotics can disrupt gut homeostasis and significantly raise the risk of allergic diseases. Thus, changes in the quantity or diversity of gut microbes affect oral toleranace through interations of microbial molecules with pattern recognition receptors on immune cells and confer susceptibility to food allergies. On the other hand, short chain fatty acids which are fermentation end products of insoluble fibers by intestinal micoorganisms have been shown to confer protective effects on food allergy. As a preventive and therapeutic treatment for food allergies, probiotics have gained widespread attention in recent years. Reintroducing certain commensal microbes, such as Clostridia, both in animal models and clinical trials led to the prevention or resolution of allergic symptoms. This review highlights recent progress in our understanding of the gut microbiota's role in food allergy. However, mechanistic details underlying the anti-allergic effects of probiotics and the interaction between the gut microbiota and the immune system remain circumstantial and are not fully understood. Future studies should address possible factors and underlying mechanisms for microbiota-host interactions and gut immunity, as well as the efficacy, safety, and appropriate use of probiotics in establishing a standard treatment regimen for food allergies.


Assuntos
Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/microbiologia , Microbioma Gastrointestinal/imunologia , Animais , Antibacterianos/efeitos adversos , Pré-Escolar , Disbiose/imunologia , Ácidos Graxos Voláteis/imunologia , Feminino , Hipersensibilidade Alimentar/prevenção & controle , Hipersensibilidade Alimentar/terapia , Humanos , Hipótese da Higiene , Lactente , Recém-Nascido , Masculino , Leite Humano/imunologia , Leite Humano/microbiologia , Parto/imunologia , Gravidez , Prevalência , Probióticos/uso terapêutico
20.
Front Immunol ; 9: 2534, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30450101

RESUMO

There is considerable interest in expanding B cell-targeted therapies in human autoimmune diseases. However, clinical trials in human primary biliary cholangitis (PBC) using a chimeric antibody against human CD20 (hCD20) have showed limited efficacy. Two potential explanations for these disappointing results are the appearance of anti-drug antibodies (ADAs) and the high frequency of patients with moderate PBC or patients who had failed ursodeoxycholic acid treatment. Here, we studied a novel humanized IgG1 antibody against hCD20 and explored its efficacy in early stage PBC using a well-defined murine model. We developed a unique murine model consisting of dnTGF-ßRII mice expressing hCD20 and human Fcγ receptors (hFcγRs). Beginning at 4-6 weeks of age, equivalent to stage I/II human PBC, female mice were given weekly injections of an anti-hCD20 antibody (TKM-011) or vehicle control, and monitored for liver histology as well as a broad panel of immunological readouts. After 16 weeks' treatment, we observed a significant reduction in portal inflammation, a decrease in liver-infiltrating mononuclear cells as well as a reduction in liver CD8+ T cells. Importantly, direct correlations between numbers of liver non-B cells and B cells (r = 0.7426, p = 0.0006) and between numbers of liver memory CD8+ T cells and B cells (r = 0.6423, p = 0.0054) were apparent. Accompanying these changes was a dramatic reduction in anti-mitochondrial antibodies (AMAs), interleukin (IL)-12p40 and IL-5, and elevated levels of the anti-inflammatory chemokine CXCL1/KC. In mice that developed ADAs, clinical improvements were less pronounced. Sustained treatment with B cell-targeted therapies may broadly inhibit effector pathways in PBC, but may need to be administered early in the natural history of PBC.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunoglobulina G/uso terapêutico , Imunoterapia/métodos , Inflamação/terapia , Cirrose Hepática Biliar/terapia , Fígado/imunologia , Animais , Anticorpos Monoclonais Humanizados/imunologia , Antígenos CD20/genética , Antígenos CD20/imunologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina G/imunologia , Inflamação/imunologia , Interleucina-10/genética , Cirrose Hepática Biliar/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptores de IgG/genética
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