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1.
Sci Total Environ ; 932: 173069, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38723974

RESUMO

The exposure to cooking organic aerosols (COA) is closely related to people's daily lives. Despite extensive investigations into COA's model compounds like oleic acid, the intricacies of heterogeneous ozonolysis of real COA and the effects of ambient conditions like humidity remain elusive. In this work, the ozonolysis of COA proxies from heated peanut oil emissions was investigated using diffuse reflectance infrared Fourier transform (DRIFTS) spectroscopy, and proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS). We found that humidity hinders the reaction between ozone and CC double bonds due to the competitive adsorption of water and ozone on COA. Although visible light has little influence on the ozonolysis of COA in the absence of humidity, the ozonolytic CO production is significantly promoted by visible light in the presence of humidity. It may be attributed to the formation of water-derived reactive oxygen species (ROS, mainly HO•) from the photosensitization of polycyclic aromatic hydrocarbons (PAHs) in COA. We also found that humidity can enhance the depolymerization of carboxylic acid dimers and hydrolysis of intrinsic acetals in the COA. Moreover, humidity promotes the release of VOCs during both the dark and light ozonolysis of COA. This work reveals the important roles of humidity-responsive and photo-responsive components in COA during its ozonolysis, and the change in VOC release may guide the control of human VOC exposure in indoor air.

2.
PLoS One ; 17(3): e0254469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35239671

RESUMO

Chediak-Higashi syndrome, caused by mutations in the Lysosome Trafficking Regulator (Lyst) gene, is a recessive hypopigmentation disorder characterized by albinism, neuropathies, neurodegeneration, and defective immune responses, with enlargement of lysosomes and lysosome-related organelles. Although recent studies have suggested that Lyst mutations impair the regulation of sizes of lysosome and lysosome-related organelle, the underlying pathogenic mechanism of Chediak-Higashi syndrome is still unclear. Here we show striking evidence that deficiency in LYST protein function leads to accumulation of photoreceptor outer segment phagosomes in retinal pigment epithelial cells, and reduces adhesion between photoreceptor outer segment and retinal pigment epithelial cells in a mouse model of Chediak-Higashi syndrome. In addition, we observe elevated levels of cathepsins, matrix metallopeptidase (MMP) 3 and oxidative stress markers in the retinal pigment epithelium of Lyst mutants. Previous reports showed that impaired degradation of photoreceptor outer segment phagosomes causes elevated oxidative stress, which could consequently lead to increases of cysteine cathepsins and MMPs in the extracellular matrix. Taken together, we conclude that the loss of LYST function causes accumulation of phagosomes in the retinal pigment epithelium and elevation of several extracellular matrix-remodeling proteases through oxidative stress, which may, in turn, reduce retinal adhesion. Our work reveals previously unreported pathogenic events in the retinal pigment epithelium caused by Lyst deficiency. The same pathogenic events may be conserved in other professional phagocytic cells, such as macrophages in the immune system, contributing to overall Chediak-Higashi syndrome pathology.


Assuntos
Peptídeo Hidrolases
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 250: 119316, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33418475

RESUMO

Abnormal levels of glutathione (GSH) and glutathione oxidized (GSSG) usually relates to some diseases, thus quantifying the amount of GSH or GSSG is of great significance. A label-free sensing assay based on the enzyme-mimicking property of Cytidine-Au nanoclusters (Cy-AuNCs) was demonstrated for colorimetric detection of GSH, GSSG and glutathione reductase (GR). Firstly, obvious blue color accompanied with an absorption peak at 652 nm was observed due to the high peroxidase-like activity of Cy-AuNCs toward 3,3',5,5'-tetramethylbenzidine (TMB). Then, in the presence of target, the mimetic activity of Cy-AuNCs could be strongly inhibited and used to achieve the visualization detection. The inhibition effect arose from the surface interaction between GSH and Cy-AuNCs. Linear relationships between absorbance response and concentration were obtained between 0 and 0.4 mM for GSH, 0-2.5 mM for GSSG and 0-0.2 U/mL for GR. The limit of detection (LOD) was calculated as low as 0.01 mM, 0.03 mM and 0.003 U/mL for GSH, GSSG and GR, respectively. Furthermore, the proposed method displayed rapid response, easy procedure and high selectivity.


Assuntos
Colorimetria , Ouro , Citidina , Glutationa , Dissulfeto de Glutationa , Glutationa Redutase , Peroxidase , Peroxidases
4.
J Colloid Interface Sci ; 557: 301-310, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525667

RESUMO

The slow Fe3+/Fe2+ conversion and difficult reactants contact are the main challenges for H2O2 activation using heterogeneous iron-based catalysts. As a typical two-dimensional layered nanomaterial, molybdenum sulfide holds great promise for promoting such process as co-catalysts, but its combination with solid iron catalysts is rarely reported. In this work, we fabricated a novel heterogeneous photocatalyst by directly anchoring amorphous MoSx onto the PAN fibers with hemin via an adsorption and in-situ transformation method. The detailed characterizations show the successful assembly of hemin and MoSx with the fibrous support through axial coordination and electrostatic bonding, respectively. Taking the degradation of organic dyes as model reactions, the as-prepared catalyst achieved remarkably high and stable catalytic performance in the presence of H2O2 under visible light irradiation, which was much superior to that of the single hemin or MoSx supported fibrous catalyst. The enhanced photocatalytic activity is mainly attributed to (i) the excellent adsorption capability of MoSx, which allows the catalyst to easily capture the reactants and (ii) the accelerated rate-limiting step of Fe3+/Fe2+ conversion. In addition, we also explored the MoSx co-catalytic effect on the other iron-based heterogeneous H2O2 activation systems (such as supported Fe3+ or FePc), and similar enhancing effect was observed. Our findings provide a facile and promising strategy to rationally design the advanced oxidation processes for environmental remediation.

5.
Int J Ophthalmol ; 10(11): 1768-1770, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29181323

RESUMO

We introduce a new interpretation and quantitative method for computerized diplopia test. By comparing this new method to the Hess screen test, we validate its applicability among 304 patients with ocular motor nerve palsy. This new method shows great assistant value as the Hess screen test in making accurate diagnosis and quantitative evaluation the severity of diplopia. Furthermore, it is more convenient and suitable for daily clinical use.

6.
Neural Regen Res ; 12(5): 826-830, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28616041

RESUMO

Abducens nerve palsy (ANP) is commonly seen in patients with diabetes mellitus. The validity of acupuncture as a traditional Chinese medicine method in peripheral nerve repair is well established. However, its efficacy in randomized controlled trials remains unclear. Herein, we designed a protocol for a prospective, single-center, randomized controlled trial to investigate the effect of intraorbital electroacupuncture on diabetic ANP. We plan to recruit 60 patients with diabetic ANP, and randomly divide them into treatment and control groups. Patients in both groups will continue their glucose-lowering therapy. A neural nutrition drug will be given to both groups for six weeks. The treatment group will also receive intraorbital electroacupuncture therapy. We will assess efficacy of treatment, eyeball movement, diplopia deviation and the levels of fasting blood-glucose and glycosylated hemoglobin before treatment at 2, 4, and 6 weeks after treatment. The efficacy and recurrence will be investigated during follow-up (1 month after intervention). This protocol was registered at Chinese Clinical Trial Registry on 16 January 2015 (ChiCTR-IPR-15005836). This study was approved by the Ethics Committee of First Affiliated Hospital of Harbin Medical University of China (approval number: 201452). All protocols will be in accordance with Declaration of Helsinki, formulated by the World Medical Association. Written informed consent will be provided by participants. We envisage that the results of this clinical trial will provide evidence for promoting clinical use of this new therapy for management of ANP.

8.
Proc Natl Acad Sci U S A ; 113(21): 5928-33, 2016 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-27162368

RESUMO

Sphingolipids exhibit extreme functional and chemical diversity that is in part determined by their hydrophobic moiety, ceramide. In mammals, the fatty acyl chain length variation of ceramides is determined by six (dihydro)ceramide synthase (CerS) isoforms. Previously, we and others showed that mutations in the major neuron-specific CerS1, which synthesizes 18-carbon fatty acyl (C18) ceramide, cause elevation of long-chain base (LCB) substrates and decrease in C18 ceramide and derivatives in the brain, leading to neurodegeneration in mice and myoclonus epilepsy with dementia in humans. Whether LCB elevation or C18 ceramide reduction leads to neurodegeneration is unclear. Here, we ectopically expressed CerS2, a nonneuronal CerS producing C22-C24 ceramides, in neurons of Cers1-deficient mice. Surprisingly, the Cers1 mutant pathology was almost completely suppressed. Because CerS2 cannot replenish C18 ceramide, the rescue is likely a result of LCB reduction. Consistent with this hypothesis, we found that only LCBs, the substrates common for all of the CerS isoforms, but not ceramides and complex sphingolipids, were restored to the wild-type levels in the Cers2-rescued Cers1 mutant mouse brains. Furthermore, LCBs induced neurite fragmentation in cultured neurons at concentrations corresponding to the elevated levels in the CerS1-deficient brain. The strong association of LCB levels with neuronal survival both in vivo and in vitro suggests high-level accumulation of LCBs is a possible underlying cause of the CerS1 deficiency-induced neuronal death.


Assuntos
Encéfalo/metabolismo , Ceramidas , Expressão Gênica , Proteínas de Membrana/deficiência , Neuritos , Doenças Neurodegenerativas , Esfingosina N-Aciltransferase/biossíntese , Esfingosina N-Aciltransferase/deficiência , Animais , Encéfalo/patologia , Sobrevivência Celular , Ceramidas/biossíntese , Ceramidas/genética , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Mutantes , Neuritos/metabolismo , Neuritos/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Esfingolipídeos/biossíntese , Esfingolipídeos/genética , Esfingosina N-Aciltransferase/genética
9.
Invest Ophthalmol Vis Sci ; 57(3): 877-88, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26978024

RESUMO

PURPOSE: Retinal detachments (RDs), a separation of the light-sensitive tissue of the retina from its supporting layers in the posterior eye, isolate retinal cells from their normal supply of nourishment and can lead to their deterioration and death. We identified a new, spontaneous murine model of exudative retinal detachment, nm3342 (new mutant 3342, also referred to as rpea1: retinal pigment epithelium atrophy 1), which we characterize herein. METHODS: The chromosomal position for the recessive nm3342 mutation was determined by DNA pooling, and the causative mutation was discovered by comparison of whole exome sequences of mutant and wild-type controls. The effects of the mutation were examined in longitudinal studies by clinical evaluation, electroretinography (ERG), light microscopy, and marker and Western blot analyses. RESULTS: New mutant 3342, nm3342, also referred to as rpea1, causes an early-onset, complete RD on the ABJ/LeJ strain background, and central exudative RD and late-onset RPE atrophy on the C57BL/6J background. The ERG responses were normal at 2 months of age but deteriorate as mice age, concomitant with progressive pan-retinal photoreceptor loss. Genetic analysis localized rpea1 to mouse chromosome 2. By high-throughput sequencing of a whole exome capture library of an rpea1/rpea1 mutant and subsequent sequence analysis, a splice donor site mutation in the Prkcq (protein kinase C, θ) gene, was identified, leading to a skipping of exon 6, frame shift and premature termination. Homozygotes with a Prkcq-targeted null allele (Prkcqtm1Litt) have similar retinal phenotypes as homozygous rpea1 mice. We determined that the PKCθ protein is abundant in the lateral surfaces of RPE cells and colocalizes with both tight and adherens junction proteins. Phalloidin-stained RPE whole mounts showed abnormal RPE cell morphology with aberrant actin ring formation. CONCLUSIONS: The homozygous Prkcqrpea1 and the null Prkcqtm1Litt mutants are reliable novel mouse models of RD and can also be used to study the effects of the disruption of PRKCQ (PKCθ) signaling in RPE cells.


Assuntos
DNA/genética , Modelos Animais de Doenças , Mutação , Proteína Quinase C-delta/genética , Descolamento Retiniano/patologia , Epitélio Pigmentado da Retina/patologia , Animais , Atrofia , Western Blotting , Análise Mutacional de DNA , Eletrorretinografia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Células Fotorreceptoras de Vertebrados , Proteína Quinase C-delta/metabolismo , Descolamento Retiniano/enzimologia , Descolamento Retiniano/genética , Epitélio Pigmentado da Retina/enzimologia , Epitélio Pigmentado da Retina/fisiopatologia , Tomografia de Coerência Óptica
10.
Adv Exp Med Biol ; 854: 745-50, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26427484

RESUMO

Regulation of vesicle trafficking to lysosomes and lysosome-related organelles (LROs) as well as regulation of the size of these organelles are critical to maintain their functions. Disruption of the lysosomal trafficking regulator (LYST) results in Chediak-Higashi syndrome (CHS), a rare autosomal recessive disorder characterized by oculocutaneous albinism, prolonged bleeding, severe immunodeficiency, recurrent bacterial infection, neurologic dysfunction and hemophagocytic lympohistiocytosis (HLH). The classic diagnostic feature of the syndrome is enlarged LROs in all cell types, including lysosomes, melanosomes, cytolytic granules and platelet dense bodies. The most striking CHS ocular pathology observed is an enlargement of melanosomes in the retinal pigment epithelium (RPE), which leads to aberrant distribution of eye pigmentation, and results in photophobia and decreased visual acuity. Understanding the molecular function of LYST and identification of its interacting partners may provide therapeutic targets for CHS and other diseases associated with the regulation of LRO size and/or vesicle trafficking, such as asthma, urticaria and Leishmania amazonensis infections.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Lisossomos/metabolismo , Melanossomas/metabolismo , Organelas/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Síndrome de Chediak-Higashi/metabolismo , Síndrome de Chediak-Higashi/fisiopatologia , Humanos , Fotofobia/metabolismo , Fotofobia/fisiopatologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/fisiopatologia , Acuidade Visual
11.
Zhongguo Zhen Jiu ; 33(11): 975-9, 2013 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-24494281

RESUMO

OBJECTIVE: To observe the difference in the clinical efficacy on oculomotor impairment between electroacupuncture and acupuncture and explore the best therapeutic method in the treatment of this disease. METHODS: Sixty cases of oculomotor impairment were randomized into an electroacupuncture group and an acupuncture group, 30 cases in each one. In the electroacupuncture group, the points were selected on extraocular muscles, the internal needling technique in the eye was used in combination of electroacupuncture therapy. In the acupuncture group, the points and needling technique were same as the electroacupuncture group, but without electric stimulation applied. The treatment was given 5 times a week, 15 treatments made one session. After 3 sessions of treatment, the clinical efficacy, palpebral fissure size, pupil size, oculomotor range and the recovery in diplopia were compared before and after treatment in the two groups. RESULTS: In the electroacupuncture group, the palpebral fissure size was (9.79+/-2.65)mm and the eyeball shifting distance was (18.12+/-1. 30)mm, which were hig-her than (8.23+/-2.74)mm and (16.71+/-1. 44)mm respectively in the acupuncture group. In the electroacupuncture group, the pupil diameter was (0. 44 +/-0. 42)mm, which was less than (0. 72 +/- 0. 53)mm in the acupuncture group, indicating the significant difference (all P<0. 05). The cured rate was 63. 33% (19/30) and the total effective rate was 93.33% (28/30) in the electroacupuncture group, which was better than 36.67% (11/30) and 83. 333 (25/30) in the acupuncture group separately, indicating the significant difference (all P<0. 05). CONCLUSION: Electroacupuncture presents the obvious advantages in the treatment of oculomotor impairment, characterized as quick and high effect, short duration of treatment and remarkable improvements in clinical symptoms, there are important significance for the improvement of survival quality of patients.


Assuntos
Eletroacupuntura , Doenças do Nervo Oculomotor/terapia , Nervo Oftálmico/lesões , Pontos de Acupuntura , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Oculomotor/fisiopatologia , Nervo Oftálmico/fisiopatologia , Resultado do Tratamento , Adulto Jovem
13.
BMC Microbiol ; 12: 144, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22817758

RESUMO

BACKGROUND: Bacterial infections have been linked to malignancies due to their ability to induce chronic inflammation. We investigated the association of oral bacteria in oral squamous cell carcinoma (OSCC/tumor) tissues and compared with adjacent non-tumor mucosa sampled 5 cm distant from the same patient (n = 10). By using culture-independent 16S rRNA approaches, denaturing gradient gel electrophoresis (DGGE) and cloning and sequencing, we assessed the total bacterial diversity in these clinical samples. RESULTS: DGGE fingerprints showed variations in the band intensity profiles within non-tumor and tumor tissues of the same patient and among the two groups. The clonal analysis indicated that from a total of 1200 sequences characterized, 80 bacterial species/phylotypes were detected representing six phyla, Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria, Actinobacteria and uncultivated TM7 in non-tumor and tumor libraries. In combined library, 12 classes, 16 order, 26 families and 40 genera were observed. Bacterial species, Streptococcus sp. oral taxon 058, Peptostreptococcus stomatis, Streptococcus salivarius, Streptococcus gordonii, Gemella haemolysans, Gemella morbillorum, Johnsonella ignava and Streptococcus parasanguinis I were highly associated with tumor site where as Granulicatella adiacens was prevalent at non-tumor site. Streptococcus intermedius was present in 70% of both non-tumor and tumor sites. CONCLUSIONS: The underlying changes in the bacterial diversity in the oral mucosal tissues from non-tumor and tumor sites of OSCC subjects indicated a shift in bacterial colonization. These most prevalent or unique bacterial species/phylotypes present in tumor tissues may be associated with OSCC and needs to be further investigated with a larger sample size.


Assuntos
Bactérias/classificação , Biodiversidade , Carcinoma de Células Escamosas/microbiologia , Carcinoma de Células Escamosas/patologia , Mucosa Bucal/microbiologia , Neoplasias Bucais/microbiologia , Neoplasias Bucais/patologia , Bactérias/isolamento & purificação , Clonagem Molecular , Eletroforese em Gel de Gradiente Desnaturante , Feminino , Humanos , Masculino , Metagenoma , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Zhongguo Zhen Jiu ; 31(3): 286-8, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21644327

RESUMO

Collecting information from the database of China National Knowledge Information (CNKI) and VIP database of Chinese Journals, an overall analysis and review on treatment of oculomotor paralysis with electroacupuncture in recently years are made in the paper. The electroacupuncture, which can provide constant stimulation and reinforce the effect of acupuncture, is the major therapy to treat oculomotor paralysis. However, the best stimulate threshold of electroacupuncture on oculorotary muscles has not been reported yet. The parameters of electroacupuncture adopted in clinic are not standardized, which lead to unfavorable therapeutic effect as well as unclear mechanism of treatment. Therefore, it is suggested that the study should focus on enhancing the research level and broadening researcher's mind to explore the best parameter for the electroacupuncture stimulation on the oculorotary muscles, to make clear the mechanism of treatment and to search for valuable observation indicators in the future.


Assuntos
Eletroacupuntura , Oftalmoplegia/terapia , Pontos de Acupuntura , Humanos
15.
FEMS Immunol Med Microbiol ; 61(3): 269-77, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21205002

RESUMO

In the oral cavity, chronic inflammation has been observed at various stages of oral squamous cell carcinomas (OSCC). Such inflammation could result from persistent mucosal or epithelial cell colonization by microorganisms. There is increasing evidence of the involvement of oral bacteria in inflammation, warranting further studies on the association of bacteria with the progression of OSCC. The objective of this study was to evaluate the diversity and relative abundance of bacteria in the saliva of subjects with OSCC. Using 454 parallel DNA sequencing, ∼58,000 PCR amplicons that span the V4-V5 hypervariable region of rRNAs from five subjects were sequenced. Members of eight phyla (divisions) of bacteria were detected. The majority of classified sequences belonged to the phyla Firmicutes (45%) and Bacteroidetes (25%). Further, 52 different genera containing approximately 860 (16.51%) known species were identified and 1077 (67%) sequences belonging to various uncultured bacteria or unclassified groups. The species diversity estimates obtained with abundance-based coverage estimators and Chao1 were greater than published analyses of other microbial profiles from the oral cavity. Fifteen unique phylotypes were present in all three OSCC subjects.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Carcinoma de Células Escamosas/microbiologia , Neoplasias Bucais/microbiologia , Saliva/microbiologia , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Metagenoma , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
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