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1.
PLoS Biol ; 22(5): e3002636, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38743770

RESUMO

Periodic patterning requires coordinated cell-cell interactions at the tissue level. Turing showed, using mathematical modeling, how spatial patterns could arise from the reactions of a diffusive activator-inhibitor pair in an initially homogeneous 2D field. Most activators and inhibitors studied in biological systems are proteins, and the roles of cell-cell interaction, ions, bioelectricity, etc. are only now being identified. Gap junctions (GJs) mediate direct exchanges of ions or small molecules between cells, enabling rapid long-distance communications in a cell collective. They are therefore good candidates for propagating nonprotein-based patterning signals that may act according to the Turing principles. Here, we explore the possible roles of GJs in Turing-type patterning using feather pattern formation as a model. We found 7 of the 12 investigated GJ isoforms are highly dynamically expressed in the developing chicken skin. In ovo functional perturbations of the GJ isoform, connexin 30, by siRNA and the dominant-negative mutant applied before placode development led to disrupted primary feather bud formation. Interestingly, inhibition of gap junctional intercellular communication (GJIC) in the ex vivo skin explant culture allowed the sequential emergence of new feather buds at specific spatial locations relative to the existing primary buds. The results suggest that GJIC may facilitate the propagation of long-distance inhibitory signals. Thus, inhibition of GJs may stimulate Turing-type periodic feather pattern formation during chick skin development, and the removal of GJ activity would enable the emergence of new feather buds if the local environment were competent and the threshold to form buds was reached. We further propose Turing-based computational simulations that can predict the sequential appearance of these ectopic buds. Our models demonstrate how a Turing activator-inhibitor system can continue to generate patterns in the competent morphogenetic field when the level of intercellular communication at the tissue scale is modulated.


Assuntos
Comunicação Celular , Plumas , Junções Comunicantes , Animais , Junções Comunicantes/metabolismo , Plumas/crescimento & desenvolvimento , Plumas/metabolismo , Embrião de Galinha , Conexinas/metabolismo , Conexinas/genética , Padronização Corporal/fisiologia , Galinhas , Pele/metabolismo , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/genética
2.
Bioessays ; 44(8): e2100276, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35770783

RESUMO

The Endosomal Sorting Complexes Required for Transport (ESCRTs) drive membrane remodeling in a variety of cellular processes that include the formation of endosomal intralumenal vesicles (ILVs) during multivesicular body (MVB) biogenesis. During MVB sorting, ESCRTs recognize ubiquitin (Ub) attached to membrane protein cargo and execute ILV formation by controlling the activities of ESCRT-III polymers regulated by the AAA-ATPase Vps4. Exactly how these events are coordinated to ensure proper cargo loading into ILVs remains unclear. Here we discuss recent work documenting the ability of Bro1, an ESCRT-associated Ub-binding protein, to coordinate ESCRT-III and Vps4-dependent ILV biogenesis with upstream events such as cargo recognition.


Assuntos
Corpos Multivesiculares , Proteínas de Saccharomyces cerevisiae , Complexos Endossomais de Distribuição Requeridos para Transporte/química , Endossomos/metabolismo , Corpos Multivesiculares/metabolismo , Transporte Proteico , Proteínas de Saccharomyces cerevisiae/metabolismo , Ubiquitina/metabolismo
3.
Eur Spine J ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907066

RESUMO

PURPOSE: This study aimed to consolidate the evidence regarding the prognostic influence of sarcopenia in degenerative lumbar spine surgeries. METHODS: A literature search of public databases was conducted up to Nov 15, 2023 using combinations of the key words "sarcopenia" and "lumbar spine surgery". Eligible studies were those that focused on adults undergoing decompression or fusion surgery for degenerative lumbar spine diseases, and compared the outcomes between patients with and without preoperative sarcopenia. Primary outcomes were change in ODI and back and leg pain VAS pain scores. Secondary outcomes were changes in Eq. 5D, JOA, SFHS-p scores, and LOS. RESULTS: Ultimately, nine retrospective studies with a total of 993 patients were included. Sarcopenic patients exhibited significantly worse functional improvement as assessed by ODI compared to non-sarcopenic patients (pooled standardized mean difference [pSMD] = 0.53, 95% confidence interval [CI]: 0.17-0.90). Back pain (pSMD = 0.31, 95% CI:0.15-0.47) and leg pain (pSMD = 0.21, 95% CI:0.02 - 0.39) improvement were also less in sarcopenic patients. Non-sarcopenic patients had greater improvements in Eq. 5D (pSMD = 0.25) and SFHS-p (pSMD = 0.39), and shorter LOS (pSMD = 0.62). CONCLUSIONS: As compared to patients without sarcopenia, those with sarcopenia undergoing lumbar spine surgery for degenerative diseases have lower improvements in functional ability, quality of life, physical health, pain relief and extended hospitalization compared to those without sarcopenia.

4.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34518236

RESUMO

Bluefin tuna (BFT), highly prized among consumers, accumulate high levels of mercury (Hg) as neurotoxic methylmercury (MeHg). However, how Hg bioaccumulation varies among globally distributed BFT populations is not understood. Here, we show mercury accumulation rates (MARs) in BFT are highest in the Mediterranean Sea and decrease as North Pacific Ocean > Indian Ocean > North Atlantic Ocean. Moreover, MARs increase in proportion to the concentrations of MeHg in regional seawater and zooplankton, linking MeHg accumulation in BFT to MeHg bioavailability at the base of each subbasin's food web. Observed global patterns correspond to levels of Hg in each ocean subbasin; the Mediterranean, North Pacific, and Indian Oceans are subject to geogenic enrichment and anthropogenic contamination, while the North Atlantic Ocean is less so. MAR in BFT as a global pollution index reflects natural and human sources and global thermohaline circulation.


Assuntos
Mercúrio/efeitos adversos , Mercúrio/metabolismo , Atum/metabolismo , Animais , Disponibilidade Biológica , Poluição Ambiental/efeitos adversos , Feminino , Cadeia Alimentar , Masculino , Compostos de Metilmercúrio/metabolismo , Oceanos e Mares , Água do Mar , Poluentes Químicos da Água/metabolismo
5.
J Formos Med Assoc ; 123(5): 613-619, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38195318

RESUMO

BACKGROUND: /Purpose: To achieve the World Health Organization goal of eliminating viral hepatitis by 2030, a key strategy in resource-limited areas is to identify the areas with high prevalence and to prioritize screening and treatment intervention. We hypothesized that a hospital-based laboratory database could be used to estimate the township- and village-specific anti-hepatitis C virus (HCV) prevalence. METHODS: Yunlin County Public Health Bureau has been collecting anti-HCV test data from eight major hospitals. Township- and village-specific screening testing rates and anti-HCV prevalence were calculated for residents 40 years or older. A township with a wide range of anti-HCV prevalence rates was selected for outreach universal screening and for validating the village-specific prevalence of anti-HCV in the analysis of the data from the hospitals. RESULTS: The overall anti-HCV screening testing rate in Yunlin County was 30.4 %, whereas the anti-HCV prevalence rate for persons 40 years or older was 15.4 %. The village-specific anti-HCV prevalence rates ranged from 3.8 % to 85.8 %. Community-based screening was conducted in Kouhu Township. The village-specific anti-HCV prevalence rates ranged from 0 % to 18.8 %. Three of the four villages had the highest village-specific anti-HCV prevalence in the community-based study and the hospital-based study. Additionally, 95.8 % of the new HCV cases detected by universal screening received anti-HCV therapy. CONCLUSION: The hospital-based database provided a framework for identifying the villages with high anti-HCV prevalence. Additionally, community-based universal screening should be prioritized for villages with high prevalence in hospital-based databases.


Assuntos
Hepatite C , Programas de Rastreamento , Humanos , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Prevalência , Adulto , Pessoa de Meia-Idade , Feminino , Idoso , Masculino , Anticorpos Anti-Hepatite C/sangue , Hospitais/estatística & dados numéricos , Hepacivirus/imunologia , População Rural/estatística & dados numéricos
6.
Medicina (Kaunas) ; 60(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38399587

RESUMO

Background and Objectives: Adolescent idiopathic scoliosis (AIS) is a prevalent three-dimensional spinal disorder, with a multifactorial pathogenesis, including genetics and environmental aspects. Treatment options include non-surgical and surgical treatment. Surgical interventions demonstrate positive outcomes in terms of deformity correction, pain relief, and improvements of the cardiac and pulmonary function. Surgical complications, including excessive blood loss and neurologic deficits, are reported in 2.27-12% of cases. Navigation-assisted techniques, such as the O-arm system, have been a recent focus with enhanced precision. This study aims to evaluate the results and complications of one-stage posterior instrumentation fusion in AIS patients assisted by O-arm navigation. Materials and Methods: This retrospective study assesses 55 patients with AIS (12-28 years) who underwent one-stage posterior instrumentation correction supported by O-arm navigation from June 2016 to August 2023. We examined radiological surgical outcomes (initial correction rate, loss of correction rate, last follow-up correction rate) and complications as major outcomes. The characteristics of the patients, intraoperative blood loss, operation time, number of fusion levels, and screw density were documented. Results: Of 73 patients, 55 met the inclusion criteria. The average age was 16.67 years, with a predominance of females (78.2%). The surgical outcomes demonstrated substantial initial correction (58.88%) and sustained positive radiological impact at the last follow-up (56.56%). Perioperative complications, including major and minor, occurred in 18.18% of the cases. Two patients experienced a major complication. Blood loss (509.46 mL) and operation time (402.13 min) were comparable to the literature ranges. Trend analysis indicated improvements in operation time and blood loss over the study period. Conclusions: O-arm navigation-assisted one-stage posterior instrumentation proves reliable for AIS corrective surgery, achieving significant and sustained positive radiological outcomes, lower correction loss, reduced intraoperative blood loss, and absence of implant-related complications. Despite the challenges, our study demonstrates the efficacy and maturation of this surgical approach.


Assuntos
Cifose , Parafusos Pediculares , Escoliose , Fusão Vertebral , Cirurgia Assistida por Computador , Feminino , Humanos , Adolescente , Masculino , Escoliose/cirurgia , Escoliose/complicações , Parafusos Pediculares/efeitos adversos , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Fusão Vertebral/métodos , Imageamento Tridimensional , Tomografia Computadorizada por Raios X/métodos , Cifose/cirurgia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Vértebras Torácicas
7.
Angew Chem Int Ed Engl ; : e202403333, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787684

RESUMO

Numerous studies have shown a fact that phase transformation and/or reconstruction are likely to occur and play crucial roles in electrochemical scenarios. Nevertheless, a decisive factor behind the diverse photoelectrochemical activity and selectivity of various copper/silicon photoelectrodes is still largely debated and missing in the community, especially the possibly dynamic behaviors of metal catalyst/semiconductor interface. Herein, through in situ X-ray absorption spectroscopy and transmission electron microscope, a model system of Cu nanocrystals with well-defined facets on black p-type silicon (BSi) is unprecedentedly demonstrated to reveal the dynamic phase transformation of forming irreversible silicide at Cu nanocrystal-BSi interface during photoelectrocatalysis, which is validated to originate from the atomic interdiffusion between Cu and Si driven by light-induced dynamic activation process. Significantly, the adaptive junction at Cu-Si interface is activated by an expansion of interatomic Cu-Cu distance for CO2 electroreduction, which efficiently restricts the C-C coupling pathway but strengthens the bonding with key intermediate of *CHO for CH4 yield, resulting in a remarkable 16-fold improvement in the product ratio of CH4/C2 products and an intriguing selectivity switch. This work offers new insights into dynamic structural transformations of metal/semiconductor junction and design of highly efficient catalysts toward photosynthesis.

8.
Nano Lett ; 22(21): 8495-8501, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36279401

RESUMO

The extreme versatility of van der Waals materials originates from their ability to exhibit new electronic properties when assembled in close proximity to dissimilar crystals. For example, although graphene is inherently nonmagnetic, recent work has reported a magnetic proximity effect in graphene interfaced with magnetic substrates, potentially enabling a pathway toward achieving a high-temperature quantum anomalous Hall effect. Here, we investigate heterostructures of graphene and chromium trihalide magnetic insulators (CrI3, CrBr3, and CrCl3). Surprisingly, we are unable to detect a magnetic exchange field in the graphene but instead discover proximity effects featuring unprecedented gate tunability. The graphene becomes highly hole-doped due to charge transfer from the neighboring magnetic insulator and further exhibits a variety of atypical gate-dependent transport features. The charge transfer can additionally be altered upon switching the magnetic states of the nearest CrI3 layers. Our results provide a roadmap for exploiting proximity effects arising in graphene coupled to magnetic insulators.

9.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675115

RESUMO

This study aimed to establish a surface modification technology for ZK60 magnesium alloy implants that can degrade uniformly over time and promote bone healing. It proposes a special micro-arc oxidation (MAO) treatment on ZK60 alloy that enables the composite electrolytes to create a coating with better corrosion resistance and solve the problems of uneven and excessive degradation. A magnesium alloy bone screw made in this way was able to promote the bone healing reaction after implantation in rabbits. Additionally, it was found that the MAO-treated samples could be sustained in simulated body-fluid solution, exhibiting excellent corrosion resistance and electrochemical stability. The Ca ions deposited in the MAO coating were not cytotoxic and were beneficial in enhancing bone healing after implantation.


Assuntos
Osso e Ossos , Magnésio , Animais , Coelhos , Magnésio/farmacologia , Magnésio/química , Corrosão , Próteses e Implantes , Ligas/farmacologia , Ligas/química , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química
10.
BMC Bioinformatics ; 22(Suppl 5): 628, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641924

RESUMO

BACKGROUND: Recent studies on acute mountain sickness (AMS) have used fixed-location and fixed-time measurements of environmental and physiological variable to determine the influence of AMS-associated factors in the human body. This study aims to measure, in real time, environmental conditions and physiological variables of participants in high-altitude regions to develop an AMS risk evaluation model to forecast prospective development of AMS so its onset can be prevented. RESULTS: Thirty-two participants were recruited, namely 25 men and 7 women, and they hiked from Cuifeng Mountain Forest Park parking lot (altitude: 2300 m) to Wuling (altitude: 3275 m). Regression and classification machine learning analyses were performed on physiological and environmental data, and Lake Louise Acute Mountain Sickness Scores (LLS) to establish an algorithm for AMS risk analysis. The individual R2 coefficients of determination between the LLS and the measured altitude, ambient temperature, atmospheric pressure, relative humidity, climbing speed, heart rate, blood oxygen saturation (SpO2), heart rate variability (HRV), were 0.1, 0.23, 0, 0.24, 0, 0.24, 0.27, and 0.35 respectively; incorporating all aforementioned variables, the R2 coefficient is 0.62. The bagged trees classifier achieved favorable classification results, yielding a model sensitivity, specificity, accuracy, and area under receiver operating characteristic curve of 0.999, 0.994, 0.998, and 1, respectively. CONCLUSION: The experiment results indicate the use of machine learning multivariate analysis have higher AMS prediction accuracies than analyses utilizing single varieties. The developed AMS evaluation model can serve as a reference for the future development of wearable devices capable of providing timely warnings of AMS risks to hikers.


Assuntos
Doença da Altitude , Doença Aguda , Feminino , Humanos , Aprendizado de Máquina , Masculino , Oximetria , Estudos Prospectivos
11.
J Biol Chem ; 296: 100759, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33965375

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 global pandemic, utilizes the host receptor angiotensin-converting enzyme 2 (ACE2) for viral entry. However, other host factors might also play important roles in SARS-CoV-2 infection, providing new directions for antiviral treatments. GRP78 is a stress-inducible chaperone important for entry and infectivity for many viruses. Recent molecular docking analyses revealed putative interaction between GRP78 and the receptor-binding domain (RBD) of the SARS-CoV-2 Spike protein (SARS-2-S). Here we report that GRP78 can form a complex with SARS-2-S and ACE2 on the surface and at the perinuclear region typical of the endoplasmic reticulum in VeroE6-ACE2 cells and that the substrate-binding domain of GRP78 is critical for this interaction. In vitro binding studies further confirmed that GRP78 can directly bind to the RBD of SARS-2-S and ACE2. To investigate the role of GRP78 in this complex, we knocked down GRP78 in VeroE6-ACE2 cells. Loss of GRP78 markedly reduced cell surface ACE2 expression and led to activation of markers of the unfolded protein response. Treatment of lung epithelial cells with a humanized monoclonal antibody (hMAb159) selected for its safe clinical profile in preclinical models depleted cell surface GRP78 and reduced cell surface ACE2 expression, as well as SARS-2-S-driven viral entry and SARS-CoV-2 infection in vitro. Our data suggest that GRP78 is an important host auxiliary factor for SARS-CoV-2 entry and infection and a potential target to combat this novel pathogen and other viruses that utilize GRP78 in combination therapy.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , Proteínas de Choque Térmico/genética , Interações Hospedeiro-Patógeno/genética , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/genética , Internalização do Vírus/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Sítios de Ligação , Chlorocebus aethiops , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/virologia , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica , Proteínas de Choque Térmico/antagonistas & inibidores , Proteínas de Choque Térmico/metabolismo , Humanos , Mutação , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Transdução de Sinais , Glicoproteína da Espícula de Coronavírus/metabolismo , Resposta a Proteínas não Dobradas , Células Vero
12.
Ecotoxicol Environ Saf ; 236: 113476, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35367880

RESUMO

Using bacteriophages (phages) as environmental sanitizers has been recognized as a potential alternative method to remove bacterial contamination in vitro; however, very few studies are available on the application of phages for infection control in hospitals. Here, we performed a 3-year prospective intervention study using aerosolized phage cocktails as biocontrol agents against carbapenem-resistant Acinetobacter baumannii (CRAB) infection in the hospital. When a CRAB-infected patient was identified in an intensive care unit (ICU), their surrounding environment was chosen for phage aerosol decontamination. Before decontamination, 501 clinical specimens from the patients were subjected to antibiotic resistance analysis and phage typing. The optimal phage cocktails were a combination of different phage families or were constructed by next-evolutionary phage typing with the highest score for the host lysis zone to prevent the development of environmental CRAB phage resistance. The phage infection percentage of the antibiotic-resistant A. baumannii strains was 97.1%, whereas the infection percentage in the antibiotic-susceptible strains was 79.3%. During the phage decontamination periods from 2017 to 2019, the percentage of carbapenem-resistant A. baumannii in test ICUs decreased significantly from 65.3% to 55%. The rate of new acquisitions of CRAB infection over the three years was 4.4 per 1000 patient-days, which was significantly lower than that in the control wards (8.9 per 1000 patient-days) where phage decontamination had never been performed. In conclusion, our results support the potential of phage cocktails to decrease CRAB infection rates, and the aerosol generation process may make this approach more comprehensive and time-saving.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Infecção Hospitalar , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/prevenção & controle , Aerossóis , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Farmacorresistência Bacteriana Múltipla , Humanos , Testes de Sensibilidade Microbiana , Estudos Prospectivos
13.
Surg Innov ; 29(4): 519-525, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35482941

RESUMO

BACKGROUND: Near-infrared indocyanine green fluorescence cholangiography (NIRF) has shown promising results on delineating extra-hepatic biliary anatomy during laparoscopic cholecystectomy to avoid bile duct injury. However its routine usage remains in question. In this study, the technique was evaluated further with learning curve estimation and learning factors were observed. METHODS: One hundred ninety-nine cases which underwent laparoscopic cholecystectomy for acute or chronic cholecystitis within a 2-year period including 51 cases with initial use of NIRF by 2 surgeons were studied retrospectively. The learning curve was evaluated for a surgeon as primary objective. A case-matched comparison of the operative time between NIRF and conventional group, in terms of acute and chronic cholecystitis was also conducted as a secondary calculation. RESULTS: Learning curve was evaluated with 61% learning rate for NIRF experience. Cysto-biliary junction non-illuminated cases under fluorescent view, had mean operative time of 80.83 ± 22.82 min, which was shorter than the cysto-biliary junction illuminated cases. The NIRF group exhibited longer operative time compared with the conventional group with mean difference of 34.39 min (significant at P < .05). CONCLUSIONS: While the initial learning phase might be affected by surgeons' behavior and attitude, our results may provide a reference to learn at one's own pace and to employ NIRF teaching strategies during surgical training programs to overcome the initial phase during training period itself and facilitate universal achievement.


Assuntos
Colecistectomia Laparoscópica , Colecistite , Cirurgiões , Colangiografia/métodos , Colecistectomia Laparoscópica/métodos , Colecistite/diagnóstico por imagem , Colecistite/cirurgia , Fluorescência , Humanos , Verde de Indocianina , Curva de Aprendizado , Estudos Retrospectivos
14.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946764

RESUMO

Micro arc oxidation (MAO) is a prominent surface treatment to form bioceramic coating layers with beneficial physical, chemical, and biological properties on the metal substrates for biomaterial applications. In this study, MAO treatment has been performed to modify the surface characteristics of AZ31 Mg alloy to enhance the biocompatibility and corrosion resistance for implant applications by using an electrolytic mixture of Ca3(PO4)2 and C10H16N2O8 (EDTA) in the solutions. For this purpose, the calcium phosphate (Ca-P) containing thin film was successfully fabricated on the surface of the implant material. After in-vivo implantation into the rabbit bone for four weeks, the apparent growth of soft tissues and bone healing effects have been documented. The morphology, microstructure, chemical composition, and phase structures of the coating were identified by SEM, XPS, and XRD. The corrosion resistance of the coating was analyzed by polarization and salt spray test. The coatings consist of Ca-P compounds continuously have proliferation activity and show better corrosion resistance and lower roughness in comparison to mere MAO coated AZ31. The corrosion current density decreased to approximately 2.81 × 10-7 A/cm2 and roughness was reduced to 0.622 µm. Thus, based on the results, it was anticipated that the development of degradable materials and implants would be feasible using this method. This study aims to fabricate MAO coatings for orthopedic magnesium implants that can enhance bioactivity, biocompatibility, and prevent additional surgery and implant-related infections to be used in clinical applications.


Assuntos
Regeneração Óssea , Substitutos Ósseos/química , Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Ligas/química , Animais , Parafusos Ósseos , Linhagem Celular , Cerâmica , Corrosão , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Modelos Animais , Oxirredução , Espectroscopia Fotoeletrônica , Próteses e Implantes , Coelhos , Propriedades de Superfície , Difração de Raios X , Microtomografia por Raio-X
15.
Environ Sci Technol ; 54(7): 3988-3995, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32157880

RESUMO

Distinct spatiotemporal distributions of sea surface dissolved elemental mercury (DEM) and its air-sea exchange flux were observed in the river-dominated and monsoon-influenced East China Sea (ECS). Spatially, DEM concentrations were higher in the nearshore Changjiang diluted water (90 ± 20 to 260 ± 40 fM) than in the offshore Kuroshio water (60 ± 10 to 160 ± 40 fM) and correlated with salinity and total Hg concentrations, suggesting that the total Hg discharged from the Changjiang river is a controlling factor. In summer, monsoon-driven coastal upwelling formed a transient nearshore water mass with very elevated DEM concentrations (290 ± 20 to 320 ± 70 fM). Seasonally, DEM concentrations in all water masses were the highest in summer (120 ± 30 to 320 ± 70 fM). Estimated rate coefficients for DEM production varied seasonally and strongly correlated with sea surface temperature (SST). Hg0 evasion fluxes also peaked in summer (670 ± 380 pmol m-2 day-1), while in winter, DEM was close to equilibrium with gaseous elemental mercury in the atmosphere. Based on the air-sea Hg fluxes for all four seasons from this study and regional atmospheric deposition fluxes from others, we conclude that the ECS is a net sink of Hg annually, but it is a source of Hg to the atmosphere in summer. Moreover, the contribution of the ECS to Hg evasion may increase as a result of flood-associated high Changjiang discharge and rising SST.


Assuntos
Poluentes Atmosféricos , Mercúrio , Poluentes Químicos da Água , China , Monitoramento Ambiental , Rios , Estações do Ano
16.
Entropy (Basel) ; 22(10)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33286849

RESUMO

Conventional image entropy merely involves the overall pixel intensity statistics which cannot respond to intensity patterns over spatial domain. However, spatial distribution of pixel intensity is definitely crucial to any biological or computer vision system, and that is why gestalt grouping rules involve using features of both aspects. Recently, the increasing integration of knowledge from gestalt research into visualization-related techniques has fundamentally altered both fields, offering not only new research questions, but also new ways of solving existing issues. This paper presents a Bayesian edge detector called GestEdge, which is effective in detecting gestalt edges, especially useful for forming object boundaries as perceived by human eyes. GestEdge is characterized by employing a directivity-aware sampling window or mask that iteratively deforms to probe or explore the existence of principal direction of sampling pixels; when convergence is reached, the window covers pixels best representing the directivity in compliance with the similarity and proximity laws in gestalt theory. During the iterative process based on the unsupervised Expectation-Minimization (EM) algorithm, the shape of the sampling window is optimally adjusted. Such a deformable window allows us to exploit the similarity and proximity among the sampled pixels. Comparisons between GestEdge and other edge detectors are shown to justify the effectiveness of GestEdge in extracting the gestalt edges.

17.
J Environ Sci (China) ; 92: 200-210, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32430123

RESUMO

Aging of polyaluminum chloride (PACl) coagulants could significantly influence hydrolyzed Al speciation ruling coagulation performance. The goal of this study was to investigate Al species transformation through long-term aging and its impact on coagulation performance. Two kinds of commercial coagulants (PACl-1 and PACl-2) were stored for in-situ aging tests in six months to evaluate Al species variation with time and the performance of coagulation with natural turbid waters. The results showed that CaSO4 precipitation easily occur in a commercial PACl coagulant with time as it contains SO42- and Ca2+. It also activates the precipitation of gibbsite Al(OH)3 in PACl with aging. Through 180 days aging, both monomeric Al (Ala) and polymeric Al (Alb) substantially transform into colloidal Al (Alc) and precipitated for both PACl coagulants. At low turbidity (10 NTU), PACl-1 has a superior turbidity reduction rate than PACl-2, while PACl-2 performs a little better turbidity reduction at high turbidity (1000 NTU) regardless of aging time. With aging time, an obvious decrease in turbidity reduction for PACl-1 coagulation is observed at low turbidity of 10 NTU, while the improvement in turbidity reduction for PACl-2 coagulation by enhanced sweep flocculation can be achieved as Alb mostly transform into Alc after 150 days aging. It is concluded that dominant in-situ formed Alc after a long time hydrolysis can improve PACl coagulation efficiency in turbidity reduction by enhanced sweep flocculation, especially for low turbidity water, but the increase in preformed Alc in PACl would worsen particle destabilization after aging.


Assuntos
Purificação da Água , Hidróxido de Alumínio , Floculação
18.
Postgrad Med J ; 95(1124): 307-313, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31209183

RESUMO

BACKGROUND: Growing evidence shows links between septicaemia and non-multiple sclerosis demyelinating syndromes (NMSDS); nevertheless, epidemiological data are still very limited. This study aimed to explore the relationship between septicaemia and NMSDS in a general population. METHODS: The study included 482 781 individuals diagnosed with septicaemia and 1 892 825 age/sex-matched non-septicaemia patients for the comparison. Data were drawn from a population-based nationwide National Health Insurance Research Database Taiwan, from 1 January 2002 to 31 December 2011. The two cohorts of patients with and without septicaemia were followed up for the occurrence of NMSDS. The Cox-proportional hazard regression model was performed to estimate adjusted HR after multivariate adjustment. RESULTS: Individuals with septicaemia had a 4.17-fold (95% CI 3.21 to 5.4, p < 0.001) higher risk to develop NMSDS compared with those without septicaemia. Patients aged <65 years had a greater NMSDS risk (<45 years: HR = 6.41, 95% CI 3.65 to 11.3, p < 0.001; 45-64 years: HR = 6.66, 95% CI 3.98 to 11.2, p < 0.001). Furthermore, females with septicaemia and individuals with higher severity of septicaemia were associated with increased risks of developing NMSDS. CONCLUSIONS: Our results indicated that patients with septicaemia were likely to develop NMSDS. A possible contributing role of septicaemia in increasing the hazard of NMSDS is proposed, based on the outcome that individuals with higher severity of septicaemia carried elevated threat of encountering NMSDS.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/epidemiologia , Sepse/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/imunologia , Doenças Desmielinizantes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Glicoproteína Mielina-Oligodendrócito/imunologia , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/imunologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
19.
Indoor Air ; 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29943860

RESUMO

The accurate quantification of antibiotic-resistant bacteria in indoor air has recently attracted increasing attention. Here, we investigated whether the susceptibility of a nosocomial infection-related microbe, Acinetobacter baumannii, to strong sampling stress caused by Nuclepore filter changes as it develops resistance to a drug called colistin. Both colistin-sensitive A. baumannii (CSAB) and colistin-resistant A. baumannii (CRAB) are generally desiccation-resistant strains that can be collected by filter sampling. However, the resistance of CRAB to the three combined stresses (aerosolization, impaction, and desiccation) caused by filter sampling was 1.8 times lower than that of CSAB (P < 0.05). The sampling stresses caused by filter sampling not only reduced the culturability of A. baumannii but also destroyed proteins to result in cellular protein leakage. CRAB released 17%-38% more extracellular protein than did CSAB when they were both subjected to desiccation stress for 240 minutes (P < 0.01). The combination of using a sampling flow rate of 20 L/min and sampling for 60 minutes with a Nuclepore filter with open-face cassettes (OFCs) is recommended for collecting airborne A. baumannii. A Nuclepore filter operated with closed-face cassettes (CFCs) significantly decreased the culturability of CRAB due to desiccation effects.

20.
Ren Fail ; 40(1): 514-519, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30396306

RESUMO

OBJECTIVES: Systemic inflammation has been reported to be associated with uremic pruritus (UP). Although a vegetarian diet can reduce systemic inflammation in hemodialysis patients, the effect of vegetarian diet on UP is not clear. The purpose of the study was to know the possible effects of vegetarian diet on UP. METHODS: A cross-sectional study was done to compare the severity of UP and blood levels of systemic inflammatory markers between vegetarian and non-vegetarian hemodialysis patients. Six non-vegetarian patients with uremic pruritus changed their non-vegetarian diet to vegetarian diet for 2 months. Visual Analogue Scale (VAS) and pruritus score (PS) were used to measure the UP severity. The serum high-sensitivity C-reactive protein (hs-CRP), and interleukin-2 (IL-2) were used as markers of inflammation. RESULTS: Both the median VAS scores (p = .043) and the median PS scores (p < .001) were lower in the Vegetarian than in the non-vegetarian group. The median values of hs-CRP in Vegetarian were lower than that for the non-vegetarian (p = .020). The median value of IL-2 was also lower in Vegetarian than that of the non-vegetarian (p = .016). There were 6 non-vegetarian patients shift to vegetarian for 2 months. The pruritus score improved and IL-2 level decreased after change to vegetarian diet. CONCLUSION: We concluded that vegetarian diet might be associated with the amelioration of the uremic pruritus severity in hemodialysis patients.


Assuntos
Biomarcadores/sangue , Dieta Vegetariana , Prurido/sangue , Prurido/dietoterapia , Uremia/dietoterapia , Idoso , Proteína C-Reativa/análise , Estudos Transversais , Feminino , Humanos , Interleucina-2/sangue , Masculino , Pessoa de Meia-Idade , Diálise Renal , Índice de Gravidade de Doença , Taiwan , Uremia/complicações
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