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1.
Fa Yi Xue Za Zhi ; 40(2): 118-127, 2024 Apr 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38847025

RESUMO

In the study of age estimation in living individuals, a lot of data needs to be analyzed by mathematical statistics, and reasonable medical statistical methods play an important role in data design and analysis. The selection of accurate and appropriate statistical methods is one of the key factors affecting the quality of research results. This paper reviews the principles and applicable principles of the commonly used medical statistical methods such as descriptive statistics, difference analysis, consistency test and multivariate statistical analysis, as well as machine learning methods such as shallow learning and deep learning in the age estimation research of living individuals, and summarizes the relevance and application prospects between medical statistical methods and machine learning methods. This paper aims to provide technical guidance for the age estimation research of living individuals to obtain more scientific and accurate results.


Assuntos
Aprendizado de Máquina , Humanos , Determinação da Idade pelo Esqueleto/métodos , Análise Multivariada , Determinação da Idade pelos Dentes/métodos
2.
Nat Mater ; 21(12): 1426-1433, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36357686

RESUMO

The ability to impart multiple covarying properties into a single material represents a grand challenge in manufacturing. In the design of block copolymers (BCPs) for directed self-assembly and nanolithography, materials often balance orthogonal properties to meet constraints related to processing, structure and defectivity. Although iterative synthesis strategies deliver BCPs with attractive properties, identifying materials with all the required attributes has been difficult. Here we report a high-throughput synthesis and characterization platform for the discovery and optimization of BCPs with A-block-(B-random-C) architectures for lithographic patterning in semiconductor manufacturing. Starting from a parent BCP and using thiol-epoxy 'click' chemistry, we synthesize a library of BCPs that cover a large and complex parameter space. This allows us to readily identify feature-size-dependent BCP chemistries for 8-20-nm-pitch patterns. These blocks have similar surface energies for directed self-assembly, and control over the segregation strength to optimize the structure (favoured at higher segregation strengths) and defectivity (favoured at lower segregation strengths).


Assuntos
Polímeros , Projetos de Pesquisa , Semicondutores , Compostos de Sulfidrila
3.
J Periodontal Res ; 57(3): 533-544, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35266182

RESUMO

AIM(S): The objective of this study was to evaluate the changes in the physical and chemical properties of titanium surfaces contaminated by a Nd:YAG laser with different levels of energy and the regulation of macrophage polarization. MATERIALS AND METHODS: The titanium specimens were divided into four groups. The blank control group consisted of the above-mentioned contaminated titanium specimens, and the conditioned control group consisted of sandblasted and acid-etched (SLA) titanium surfaces. The blank control and condition control groups were sealed and preserved in a sterile dark box. There were two experimental groups treated with the Nd:YAG laser-one with 0.5 W and the second with 1.0 W. Surface characteristics were evaluated using scanning electron microscopy, surface profilometry, and contact angle assays. The macrophage viability and proliferation of mouse RAW246.7 were analysed, and the macrophage surface markers, macrophage cytokines, and inflammatory and anti-inflammatory genes were expressed. RESULTS: The Nd:YAG laser increased the hydrophilicity and roughness of the titanium surface after decontamination. Fewer RAW264.7 cells were observed on the titanium surface after Nd:YAG decontamination than on the contaminated titanium surface expressing the M1-type macrophage marker CCR7, whereas more cells were observed after decontamination than on the contaminated titanium surface expressing the M2-type macrophage marker CD206. Following Nd:YAG laser treatment, the secretion of the inflammatory cytokines IL-1ß and TNF-α by RAW264.7 cells on the titanium surface was decreased, whereas the secretion of the anti-inflammatory cytokines IL-4 and IL-10 was increased. RAW264.7 cells cultured for 3 days on the titanium surface after Nd:YAG decontamination treatment expressed significantly reduced levels of the inflammation-related genes IL-1ß, TNF-α, IL-6 and iNOS. The expression of the anti-inflammatory genes Arg-1, IL-4, IL-10 and TGF-ß by RAW264.7 cells was significantly up-regulated after 3 days of incubation on the titanium surface after Nd:YAG decontamination treatment. CONCLUSION(S): The Nd:YAG laser increased the hydrophilicity and roughness of the titanium surface after decontamination, and this change inhibited M1-type macrophage polarization and promoted M2-type macrophage polarization.


Assuntos
Implantes Dentários , Lasers de Estado Sólido , Animais , Interleucina-10 , Interleucina-4 , Macrófagos , Camundongos , Microscopia Eletrônica de Varredura , Neodímio , Propriedades de Superfície , Titânio/química , Fator de Necrose Tumoral alfa , Ítrio
4.
J Mater Sci Mater Med ; 29(4): 43, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29603028

RESUMO

This study was designed to compare the early osseointegration of titanium surfaces prepared via laser-treated/acid-etched (LA) and sandblasted/acid-etched (SLA) in dogs. Titanium implants were divided into two groups: Surfaces of the experimental group were treated via LA, while in the control group, surfaces were treated via SLA. The physical and chemical properties of LA and SLA surfaces were tested and compared. Sixteen implants with LA or SLA surfaces were placed into the tibias of four beagle dogs, each treatment group received two implants per single tibia. The dogs were sacrificed two and four weeks after implant placement. Scanning electron microscopy showed that both the LA and SLAs surface exhibited rough structures with micro pores sized 1-3 µm. In the LA surface, regular melting points were observed. However, in the SLA surface, the structure was irregular and few oxide aluminum particles still remained. Only titanium and a small amount of titanium compounds were detected on LA surfaces, while Al was found of SLA surfaces. The LA surface roughness was above that of SLA surfaces (LA: Ra: 2.1 µm; SLA: Ra :1.53 µm; P < 0.01). Both groups exhibited good osseointegration and no significant differences were found in the BIC% at two or four weeks between both groups (P > 0.05). Both groups exhibited good osseointegration; however, the LA surface was cleaner and more uniform than the SLA surface, and no significant differences were found between both groups.


Assuntos
Materiais Revestidos Biocompatíveis/química , Implantes Dentários , Planejamento de Prótese Dentária , Osseointegração , Titânio/química , Animais , Cães , Teste de Materiais , Propriedades de Superfície
5.
Fa Yi Xue Za Zhi ; 32(1): 69-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27295861

RESUMO

A case of a stillbirth with lethal type II osteogenesis imperfecta (OI) was reported. The fetus had skull fractures and craniocerebral injuries during pregnancy. Postmortem multi-sliced computed tomography (MSCT) and 3D-reconstruction were performed, followed by a medico-legal autopsy. The autopsic findings showed the typical features of type II OI, including a soft calvarium, deformed extremities, flexed and abducted hips, and uncommon features, such as white sclera, coxa vara, absence of several bones and organs, a cleft lip, and asymmetric ears. The radiologic images revealed such anomalies and variations as a cleft palate, mandibular dysplasia, spina bifida, costa cervicalis, and fusion of the ribs and vertebrae, which were difficult to detect during conventional autopsy. The paper investigated the classification, causative mutation, cause of death, and the differentiation of OI from child abuse, coming to a conclusion that OI knowledge can be of great importance to forensic pathologists and that the merits of postmortem MSCT should be emphasized in forensic pathologic examinations.


Assuntos
Tomografia Computadorizada Multidetectores/métodos , Osteogênese Imperfeita/diagnóstico , Autopsia , Criança , Morte , Evolução Fatal , Feminino , Feto , Patologia Legal , Humanos , Recém-Nascido , Osteogênese Imperfeita/fisiopatologia , Gravidez , Costelas , Crânio/patologia
6.
BMC Gastroenterol ; 14: 113, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24969847

RESUMO

BACKGROUND: The aim of this study was to evaluate whether polymorphisms of the mannose receptor C type 1 (MRC-1) and interleukin 28B (IL-28B) genes are associated with the treatment outcome of patients infected with hepatitis C virus genotypes 1 and 2 (HCV-1 and HCV-2, respectively) who are treated with peginterferon plus ribavirin (PEG-IFNα-RBV). METHODS: We analyzed the association of the patients' sustained viral responses (SVRs) to PEG-IFNα-RBV therapy with 2 single nucleotide polymorphisms (SNPs) in MRC-1 and 3 SNPs in IL-28B. We selected patients infected with either HCV-1 (n = 265) or HCV-2 (n = 195) with or without SVR. RESULTS: Among the MRC-1 SNPs, rs691005 was found to be associated with SVR in HCV-1-infected patients (P < 0.0001). The IL-28B rs8099917 SNP was found to be associated with SVR in HCV-1- and HCV-2-infected patients (HCV-1, P < 0.0001; HCV-2, P = 0.002), while IL-28B rs955155 and rs10853728 SNPs were found to be associated with SVR in HCV-1-infected patients (P = 0.003) and HCV-2-infected patients (P = 0.02), respectively. We also identified an interaction between MRC-1 rs691005 and IL-28B rs8099917 (P = 0.001). The C-T haplotype was shown to have a positive effect on SVR in HCV-1-infected patients (OR = 1.77, 95% CI = 1.2, 2.62), whereas the T-G haplotype was shown to have a negative effect on SVR in HCV-1-infected patients (OR = 0.28, 95% CI = 0.14, 0.58). CONCLUSIONS: These results suggest that SNPs of IL-28B and MRC-1 can be used as genetic markers for predicting the outcome of PEG-IFNα-RBV treatment of HCV infections.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interleucinas/genética , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Receptores Imunológicos/genética , Ribavirina/uso terapêutico , Adulto , Estudos de Casos e Controles , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/genética , Hepatite C Crônica/imunologia , Humanos , Interferons , Interleucinas/imunologia , Masculino , Glicoproteínas de Membrana , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores Imunológicos/imunologia , Resultado do Tratamento , Carga Viral
7.
Fa Yi Xue Za Zhi ; 30(3): 184-7, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25272872

RESUMO

OBJECTIVE: To summarize the subtle anatomical structures of the normal nasal bone in multi-slice spiral CT (MSCT) image through the observation of the three-dimensional images. METHODS: One hundred and twenty volunteers who had no nasal trauma and disease history were collected. The nasal was scanned using MSCT. Raw data was reconstructed into bone window images (slice thickness 0.6 mm, slice interval 0.5 mm), and then the images were imported into Syngo Imaging XS software to reconstruct three-dimensional images and to summarize the nasal bone's subtle anatomical structures. RESULTS: The subtle anatomy of normal nasal bone generally included four seams, two holes and one edge. The four seams were left and right nasal-maxillary suture, nasal-frontal seam, and internasal suture. The two holes were left and right nasal aperture. The edge of the nasal was the lower edge of the nasal bone. In addition, there was suture bone in internasal suture in some normal nose. The nasal aperture mostly was hole-like, but some nasal apertures were line shape. The nasal edge can be divided into flat type, wave-shaped type, inverted spike type, hook-shaped type and others. CONCLUSION: The anatomy diversity and individual differences in nasal bone are large. MSCT and three-dimensional image reconstruction techniques, combined with the history of trauma could distinguish between the normal anatomy and fractures.


Assuntos
Osso Nasal/anatomia & histologia , Tomografia Computadorizada Espiral , Fraturas Ósseas/diagnóstico , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Maxila , Osso Nasal/diagnóstico por imagem , Software , Tomografia Computadorizada por Raios X
8.
Indian J Ophthalmol ; 72(7): 1064-1067, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38905465

RESUMO

The aim of this study is to describe a modified technique for internal refixation of dislocated scleral-sutured polymethylmethacrylate (PMMA) intraocular lenses (IOLs) with eyelets. Three-port pars plana vitrectomy was performed. Through the scleral fixation site, a 30-gauge needle loaded with an 8-0 polypropylene suture was inserted into the vitreous cavity. The suture end was passed through the eyelet of IOL with 25-gauge forceps. Next, it was guided out of the eye through the original scleral fixation point. The end of the exterior suture was buried with a flapless intrascleral knotting technique. Six eyes of six patients were successfully treated with this technique and followed up for 6-12 months postsurgery. In all cases, there was significant improvement in uncorrected visual acuity. IOLs were stable with proper centration and no major complications. This modified technique offers an effective and minimally invasive surgical alternative for refixation of dislocated scleral-sutured PMMA IOLs with eyelets.


Assuntos
Migração do Implante de Lente Intraocular , Lentes Intraoculares , Polimetil Metacrilato , Reoperação , Esclera , Técnicas de Sutura , Acuidade Visual , Vitrectomia , Humanos , Masculino , Feminino , Técnicas de Sutura/instrumentação , Vitrectomia/métodos , Pessoa de Meia-Idade , Esclera/cirurgia , Migração do Implante de Lente Intraocular/cirurgia , Seguimentos , Idoso , Suturas , Adulto
9.
Biomater Sci ; 12(12): 3003-3026, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38695621

RESUMO

Janus structure hydrogels (JSHs) are novel materials. Their primary fabrication methods and various applications have been widely reported. JSHs are primarily composed of Janus particles (JNPs) and polysaccharide components. They exhibit two distinct physical or chemical properties, generating intriguing characteristics due to their asymmetric structure. Normally, one side (adhesive interface) is predominantly constituted of polysaccharide components, primarily serving excellent adhesion. On the other side (functional surface), they integrate diverse functionalities, concurrently performing a plethora of synergistic functions. In the biomedical field, JSHs are widely applied in anti-adhesion, drug delivery, wound healing, and other areas. It also exhibits functions in seawater desalination and motion sensing. Thus, JSHs hold broad prospects for applications, and they possess significant research value in nanotechnology, environmental science, healthcare, and other fields. Additionally, this article proposes the challenges and future work facing these fields.


Assuntos
Hidrogéis , Hidrogéis/química , Hidrogéis/farmacologia , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Animais , Polissacarídeos/química , Sistemas de Liberação de Medicamentos , Cicatrização/efeitos dos fármacos
10.
BMC Immunol ; 14: 21, 2013 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-23651608

RESUMO

Genetic polymorphisms observed in various disease states associated with sensitivity or resistance to specific treatments have been a robust area of investigation for decades, with the potential to allow clinicians to make evidence-based decisions on the appropriate course of treatment. This study aimed to evaluate whether genetic polymorphisms of the signal transducer and activator of transcription 6 gene (STAT6) could be associated with a sustained virological response (SVR) among patients infected with hepatitis C virus genotypes 1 and 2 (HCV-1 and HCV-2) who were treated with peginterferon plus ribavirin (PEG-IFNα-RBV). We analyzed the associations between SVR to PEG-IFNα-RBV therapy and 4 single nucleotide polymorphisms (SNPs) in STAT6. This study included Taiwanese Chinese patients infected with either HCV-1 (n = 265) or HCV-2 (n = 195) in the presence or absence of an SVR. Among the STAT6 SNPs examined, the dosage effect of the A allele and allele frequency in rs1059513 were inversely correlated with SVR in patients infected with HCV-1 (P = 0.0179 and P = 0.0235, respectively). This effect was not observed in patients infected with HCV-2. The GG, GGG, and GGGC STAT6 haplotypes comprising 2, 3, and 4 SNPs (rs1059513, rs703817, rs324015, and rs3024974) were found to be associated with SVR, and their presence may increase the probability of a successful treatment outcome in patients infected with HCV-1 (P = 0.0273, 0.0352, and 0.0368, respectively). Moreover, a multivariate logistic regression model for predicting an SVR revealed that the presence of the GGGC haplotype carriers mutually affected the outcome of PEG-IFNα-RBV treatment. The presence of STAT6 SNPs and the association with SVR demonstrated that STAT6 polymorphisms might influence the therapeutic outcomes of patients infected with HCV-1 under standard-of-care (SOC) treatment.


Assuntos
Povo Asiático/genética , Predisposição Genética para Doença , Hepacivirus/fisiologia , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Polimorfismo de Nucleotídeo Único/genética , Fator de Transcrição STAT6/genética , Quimioterapia Combinada , Feminino , Frequência do Gene/genética , Haplótipos/genética , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Desequilíbrio de Ligação/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Taiwan , Resultado do Tratamento
11.
J Med Virol ; 85(7): 1206-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23918539

RESUMO

This study aimed to evaluate whether genetic polymorphisms of the inducible nitric oxide synthase (iNOS) gene NOS2A could be associated with a sustained virological response (SVR) among patients infected with hepatitis C virus genotypes 1 and 2 (HCV-1 and HCV-2) who were treated with peginterferon plus ribavirin (PEG-IFNα-RBV). We analyzed the associations between SVR to PEG-IFNα-RBV therapy and two single nucleotide polymorphisms (SNPs) in NOS2A. This study included Taiwanese Chinese patients infected with either HCV-1 (n = 265) or HCV-2 (n = 195) with or without a SVR. Among the NOS2A SNPs examined, the combination of genotypes A/A and A/G of rs2248814 was inversely correlated with SVR in patients infected with HCV-1 (P = 0.0048), particularly in males (P = 0.0281). This effect was not observed in patients infected with HCV-2. The AC NOS2A haplotype comprising two SNPs (rs2248814 and rs2072324) was found to be associated with SVR, and its presence may decrease the chances for a successful outcome of treatment of patients infected with HCV-1 (P = 0.0053). HCV-1 infected patients who carried the A-C diplotype will have a lower success rate of achieving a SVR (P = 0.0117). In addition, a multivariate logistic regression model for predicting a SVR revealed that the presence of the A-C diplotype interactively affected the outcome of PEG-IFNα-RBV treatment. The presence of NOS2A SNPs and the association with SVR showed that NOS2A polymorphisms may influence the therapeutic outcomes of patients infected with HCV-1 under standard of care treatment.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Óxido Nítrico Sintase Tipo II/genética , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único , Ribavirina/uso terapêutico , Adulto , Idoso , Quimioterapia Combinada/métodos , Feminino , Genótipo , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Taiwan , Resultado do Tratamento
12.
BMC Gastroenterol ; 12: 167, 2012 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-23171003

RESUMO

BACKGROUND: The aim of this study was to evaluate whether polymorphisms in the guanine nucleotide binding (G protein), beta polypeptide 1 (GNB1) gene are associated with a rapid virological response (RVR) among HCV genotype 1 (HCV-1) and 2 (HCV-2) infected patients receiving peginterferon plus ribavirin treatment (PEG-IFNα-RBV). METHODS: We analyzed the association between RVR to PEG-IFNα-RBV therapy and 4 tagging single nucleotide polymorphisms (SNPs) of the GNB1 gene. This study included 265 HCV-1 and 195 HCV-2 infected patients in a Chinese population in Taiwan. RESULTS: Among the GNB1 SNPs examined, the combination of genotypes G/G and G/T populations of rs12126768 was significant inversely correlated with RVR in HCV-1 infected patients (P = 0.0330), whereas HCV-2 infected patients, combination of A/A and A/C genotypes populations at rs4648727 responded better to the PEG-IFNα-RBV treatment (P = 0.0089). However, there were no significant differences in the allele frequencies of those SNPs between RVR responders and non-responders. Several RVR susceptibility GNB1 haplotypes were identified, and the ACAT haplotype of the 4 SNPs may increase the successful outcomes of HCV-1 and HCV-2 infected patients (P = 0.0261 and P = 0.0253, respectively). CONCLUSION: The data for GNB1 SNPs and the association of RVR showed that GNB1 polymorphisms might be associated with the therapeutic outcomes of HCV-1 and HCV-2 infected patients under standard of care (SOC) treatment.


Assuntos
Povo Asiático/genética , Subunidades beta da Proteína de Ligação ao GTP/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Adulto , Antivirais/uso terapêutico , Distribuição de Qui-Quadrado , Intervalos de Confiança , Quimioterapia Combinada , Feminino , Frequência do Gene , Haplótipos , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Taiwan , Resultado do Tratamento
13.
Medicine (Baltimore) ; 100(7): e24780, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607828

RESUMO

ABSTRACT: The etiology of dental-supporting tissue diseases in children is multi factorial and not merely related to oral hygiene. Therefore, in the present study, we investigated the relationship between children <18 years old with allergic rhinitis (AR) and the risk of dental-supporting tissue diseases.Data from the National Health Insurance Research Database (NHIRD) of Taiwan were used to conduct a retrospective longitudinal cohort study. The study cohort comprised 378,160 patients with AR (AR group) and 378,160 patients without AR (non-AR group), who were selected through frequency matching based on age, sex, and the index year. The study patients were followed until dental-supporting tissue diseases occurrence, withdrawal from the National Health Insurance program, or December 31, 2013. Cox proportional hazards regression analysis was conducted to calculate the risk of dental-supporting tissue diseases in the AR group after adjustment for age, sex, and relative comorbidities.The adjusted HRs of periodontal, pulp, and periapical diseases in AR children were higher than those in the non-AR controls (1.51, 95% CI: 1.50 to 1.53; 1.06, 95% CI: 1.05 to 1.07, respectively). The AR to non-AR HRs of these inflammatory dental diseases were particularly higher in children <6 years old and in boys. The HRs of periodontal, pulp, and periapical diseases were greatest in those with >5 AR-related medical visits/year (5.57, 95% CI: 5.50 to 5.56; 4.06, 95% CI: 4.00 to 4.12, respectively).Children with AR had a greater risk of inflammatory dental-supporting tissue diseases, particularly those <6 years old with primary teeth, boys, and those with severe persistent AR.


Assuntos
Doenças Periodontais/epidemiologia , Rinite Alérgica/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Doenças Periodontais/etiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Taiwan/epidemiologia
14.
Ying Yong Sheng Tai Xue Bao ; 31(1): 282-292, 2020 Jan.
Artigo em Zh | MEDLINE | ID: mdl-31957406

RESUMO

Brown tide that occurred in Qinhuangdao coastal waters from 2009 to 2015 caused huge losses of local marine aquaculture and coastal tourism, with devastating effects on marine ecosystems. Nutrients are important biogenic elements for algal growth. It is of great significance to examine the fluctuation characteristics of nutrients in the process of brown tide to understand the nutritional mechanism of brown tide. Based on the survey data of 30 stations located in Qinhuangdao coastal area from April to June 2014, we analyzed nutrient characteristics during the occurrence of brown tide and its relationship with the population dynamics of Aureococcus anophagefferens. The results showed that the concentration of dissolved nitrogen (DN) in April, May and June 2014 was 265.65, 355.36 and 323.71 µg·L-1 respectively, and the concentration of dissolved organic nitrogen (DON) was 196.98, 242.88 and 177.69 µg·L-1, accounting for 74.2%, 68.3% and 54.9% of DN, respectively. The concentration of dissolved phosphorus (DP) in April, May and June was 15.95, 11.39 and 11.14 µg·L-1 respectively. In April and May, PO43--P accounted for a large proportion of the DP, 74.8% and 80.9% respectively. In June, the proportion of PO43--P in DP fell to 33.8%, and the proportion of dissolved organic phosphorus (DOP) in DP rose to 66.2%. The concentration of SiO32--Si in April, May and June was 70.95, 181.13 and 120.68 µg·L-1, respectively. Except for dissolved inorganic nitrogen (DIN) in May and DON, the distribution of other nutrients had clear characteristics that it decreased gradually from inshore to the offshore, with the relatively high concentrations in river mouth. Through R-factor analysis and nutrient structure analysis, it was found that in April, brown tide was at the development stage, and DOP might be the main driving factor for the growth of A. anophagefferens. In May, brown tide was at the maintenance stage, and water temperature became the main controlling factor. When water temperature was higher than 12 ℃, brown tide could occur. In June, brown tide began to decay, and PO43--P had greater effects on the community structure of phytoplankton. DON was the important factor causing the outbreak of brown tide, with a concentration threshold of 150 µg·L-1 and the ratio DON/DIN being greater than 1.


Assuntos
Ecossistema , Água do Mar , China , Nitrogênio , Nutrientes , Fósforo
15.
Chin Med J (Engl) ; 132(18): 2185-2191, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31425359

RESUMO

BACKGROUND: Jaw thrust has been proven as a useful test determining adequate depth of anesthesia for successful insertion of supraglottic airway device (SAD) in normal adults and children receiving intra-venous or inhalational anesthesia induction. This prospective observational study aimed to determine the feasibility and validity of this test when using as an indicator assessing adequate depth of anesthesia for successful insertion of SAD in spontaneously breathing morbidly obese patients receiving sevoflurane inhalational induction. METHODS: Thirty morbidly obese patients with a body mass index 40 to 73 kg/m undergoing bariatric surgery in Beijing Friendship Hospital from October 2018 to January 2019 were included in this study. After adequate pre-oxygenation, 5% sevoflurane was inhaled and inhalational concentration of sevoflurane was increased by 1% every 2 min. After motor responses to jaw thrust disappeared, a SAD was inserted and insertion conditions were graded. The anatomic position of SAD was assessed using a fiberoptic bronchoscope. RESULTS: The SAD was successfully inserted at the first attempt in all patients. Insertion conditions of SAD were excellent in nine patients (30%) and good in 21 patients (70%), respectively. The fiberoptic views of SAD position were adequate in 28 patients (93%). CONCLUSIONS: Jaw thrust test is a reliable indicator determining adequate anesthesia depth of sevoflurane inhalational induction for successful insertion of SAD in spontaneously breathing morbidly obese patients. CLINICAL TRIAL REGISTRATION: ChiCTR1800016868; http://www.chictr.org.cn/showproj.aspx?proj=28646.


Assuntos
Anestesia/métodos , Anestésicos Inalatórios/administração & dosagem , Anestésicos Intravenosos/administração & dosagem , Sevoflurano/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida , Estudos Observacionais como Assunto , Estudos Prospectivos
16.
Med Sci Law ; 58(1): 58-61, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29363384

RESUMO

Dental injuries, especially of the incisors, caused by punches in violent criminal attacks could be seen in daily forensic casework involving the identification of injuries to a living body. Sometimes, when there is neither circumstantial evidence nor information about the surrounding circumstances, it is difficult to discern the cause of these injuries and the manner in which they were inflicted. As an example of clinical forensic medicine, we present the case of a 58-year-old woman whose teeth were injured when fighting with her son-in-law over household affairs with no witnesses present. The two parties had conflicting stories about the cause of the woman's injury. The woman claimed that her teeth were lost while she was being beaten by her son-in-law, and the man argued that the damage to his mother-in-law's teeth was self-inflicted when she bit his fingers. The police attending the crime called for a forensic examination. Forensic practitioners analysed the mechanism of the tooth loss using multi-slice spiral computed tomography (MSCT) and imaging reconstruction technology. Local alveolar bone (medial alveolar) fracture and a small area of alveolar bone loss were found on MSCT. Thus, forensic medical experts speculated that the woman's lower central and lateral incisors were lost as a result of a violent attack and were not self-inflicted. Finally, forensic practitioners helped police in avoiding a miscarriage of justice and wrongful conviction.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/lesões , Fraturas Maxilomandibulares/diagnóstico por imagem , Abuso Físico , Perda do Osso Alveolar/etiologia , Feminino , Medicina Legal , Humanos , Fraturas Maxilomandibulares/etiologia , Pessoa de Meia-Idade , Tomografia Computadorizada Espiral
17.
Sci Adv ; 2(3): e1501571, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27051870

RESUMO

Correlating spatial chemical information with the morphology of closely packed nanostructures remains a challenge for the scientific community. For example, supramolecular self-assembly, which provides a powerful and low-cost way to create nanoscale patterns and engineered nanostructures, is not easily interrogated in real space via existing nondestructive techniques based on optics or electrons. A novel scanning probe technique called infrared photoinduced force microscopy (IR PiFM) directly measures the photoinduced polarizability of the sample in the near field by detecting the time-integrated force between the tip and the sample. By imaging at multiple IR wavelengths corresponding to absorption peaks of different chemical species, PiFM has demonstrated the ability to spatially map nm-scale patterns of the individual chemical components of two different types of self-assembled block copolymer films. With chemical-specific nanometer-scale imaging, PiFM provides a powerful new analytical method for deepening our understanding of nanomaterials.


Assuntos
Microscopia de Força Atômica/métodos , Nanoestruturas/química , Modelos Químicos , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Control Release ; 102(1): 293-306, 2005 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-15653153

RESUMO

Use of bioactive cationic peptides as gene carriers is limited by instability of their DNA complexes in vivo and by the loss of their biological activity due to undesired interactions of their bioactive parts with the DNA. To overcome the two major limitations, biodegradable high-molecular-weight form of TAT peptide (POLYTAT) sensitive to cellular redox-potential gradients was synthesized in this study by oxidative polycondensation. Physicochemical and transfection properties of DNA polyplexes based on POLYTAT were investigated and compared with polyplexes based on TAT polymer prepared by in situ template-assisted polymerization. Physicochemical properties of TAT-based polyplexes were affected by the molecular weight and method of polymerization of the TAT peptide. All TAT-based DNA polyplexes exhibited reduced cytotoxicity when compared with control polyethylenimine (PEI) polyplexes. Polyplexes based on both high-molecular-weight TAT polypeptides exhibited increased transfection efficiency compared to control TAT peptide but lower than that of PEI polyplexes. The evidence shows that transfection activity of TAT-based polyplexes is strongly dependent on the presence of chloroquine and therefore suggests that TAT polyplexes are internalized by an endocytosis. Overall, high-molecular-weight reducible polycations based on bioactive peptides has the potential as versatile carriers of nucleic acids that display low cytotoxicity and can prove to be especially beneficial in cases that require surface presentation of membrane-active or cell-specific targeting peptides.


Assuntos
DNA/genética , Produtos do Gene tat/genética , Produtos do Gene tat/metabolismo , Fragmentos de Peptídeos/genética , Polímeros/metabolismo , Transfecção/métodos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , DNA/administração & dosagem , Produtos do Gene tat/administração & dosagem , Camundongos , Fragmentos de Peptídeos/administração & dosagem , Polímeros/administração & dosagem
19.
Methods Mol Biol ; 1207: 201-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25253142

RESUMO

Galectins, a family of ß-galactoside-binding proteins, are expressed in many different phagocytic leukocytes (granulocytes, monocytes, and macrophages). A number of family members have been shown to play an important role in ingestion of particles (phagocytosis), thus contributing to clearance of damaged cells and host defense against pathogens. Here we describe procedures for analysis of the roles of galectins in phagocytosis by using galectin-3 as an example. We emphasize the function of endogenous galectin-3 as determined by comparison of phagocytosis by macrophages from galectin-3 knockout mice and wild-type mice. We focus on the role of galectin-3 in phagocytosis of pathogens and Fcγ receptor-mediated phagocytosis of opsonized cells and particles.


Assuntos
Galectina 3/metabolismo , Fagocitose , Animais , Eritrócitos/citologia , Citometria de Fluxo , Imunofluorescência , Látex , Listeria monocytogenes/fisiologia , Macrófagos/citologia , Macrófagos/microbiologia , Camundongos , Microesferas , Receptores de IgG/metabolismo , Ovinos
20.
Biomed Mater ; 7(5): 055002, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22781962

RESUMO

Titanium implants are sold in the market as storable medical devices. All the implants have a certain shelf life during which they maintain their sterility, but variations of the surface properties through this duration have not been subject to a comprehensive assessment. The aim of this study was to investigate the effects of storage methods on time-related changes of titanium surface properties. Acid-etched titanium discs (Sa = 0.82 µm) were placed in a sealed container (tradition method) or submerged in the ddH(2)O/NaCl solution (0.15 mol L(-1))/CaCl(2) solution (0.15 mol L(-1)), and new titanium discs were used as a control group. SEM and optical profiler showed that surface morphology and roughness did not change within different groups, but the XPS analysis confirmed that the surface chemistry altered by different storage protocols as the storage duration increased, and the contact angle also varied with storage methods. The storage method also affected the protein adsorption capacity and cellular response on the titanium surface. All titanium discs stored in the solution maintained their excellent bioactivity even after four weeks storage time, but titanium discs stored in a traditional manner decreased substantially in an age-dependent manner. Much effort is needed to improve the storage methods in order to maintain the bioactivity of a titanium dental implant.


Assuntos
Próteses e Implantes , Titânio , Condicionamento Ácido do Dente , Adsorção , Fosfatase Alcalina/metabolismo , Calcificação Fisiológica , Adesão Celular , Linhagem Celular , Proliferação de Células , Forma Celular , Fenômenos Químicos , Implantes Dentários , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Osteoblastos/enzimologia , Espectroscopia Fotoeletrônica , Proteínas , Propriedades de Superfície , Fatores de Tempo
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