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1.
Int J Med Sci ; 21(2): 357-368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169666

RESUMO

This study investigated the potential role of the mouse homolog of bombesin receptor-activated protein (BRAP) in imiquimod (IMQ) induced psoriasis - like skin inflammation. The expression of both human BRAP, encoded by C6orf89, and its mouse homolog, encoded by BC004004, has been found to be expressed abundantly in the keratinocytes. BC004004 knockout mice (BC004004-/-) were topically treated with IMQ daily for 7 days to test whether they were more vulnerable to psoriasis - like inflammation. We found that those mice exhibited an altered pattern of inflammation process compared to isogenic wild type control mice (BC004004+/+). BC004004-/- mice developed skin lesions with earlier and more acute onset, as well as a quicker remission. The cytokines related to pathogenesis of psoriasis also exhibited different expression patterns in IMQ treated BC004004-/- mice. On day 4 of IMQ treatment, BC004004-/- mice exhibited a higher expression level of IL-17A compared to BC004004+/+ mice, suggesting a more robust activation of Th17 cells in the knockout mice. The serum level of thymic stromal lymphopoietin (TSLP), one of the keratinocyte derived cytokines, was also increased in BC004004-/- mice and reached its peak on day 4. Knockdown of BRAP in cultured human keratinocyte-derived HaCaT cells by siRNA silencing led to increased release of TSLP. Our data suggest that the elevated of level of TSLP released from keratinocytes due to BRAP deficiency might mediate the crosstalk between the epidermal cells and immune cells and thereby contributing to the altered pathological changes observed in psoriasis - like skin lesion in knockout mice.


Assuntos
Psoríase , Receptores da Bombesina , Camundongos , Humanos , Animais , Receptores da Bombesina/genética , Receptores da Bombesina/metabolismo , Queratinócitos/metabolismo , Imiquimode/metabolismo , Inflamação/patologia , Citocinas/metabolismo , Camundongos Knockout , Modelos Animais de Doenças , Pele/patologia , Camundongos Endogâmicos BALB C
2.
Stress ; 26(1): 1-14, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36520154

RESUMO

Bombesin receptor-activated protein (BRAP) and its homologous protein in mice, which is encoded by bc004004 gene, were expressed abundantly in brain tissues with unknown functions. We treated bc004004-/- mice with chronic unpredictable mild stress (CUMS) to test whether those mice were more vulnerable to stress-related disorders. The results of forced swimming test, sucrose preference test, and open field test showed that after being treated with CUMS for 28 days or 35 days both bc004004-/- and bc004004+/+ mice exhibited behavioural changes and there was no significant difference between bc004004+/+ and bc004004-/-. However, behavioural changes were observed only in bc004004-/- mice after being exposed to CUMS for 21 days, but not in bc004004+/+ after 21-day CUMS exposure, indicating that lack of BRAP homologous protein may cause vulnerability to stress-related disorders in mice. In addition, bc004004-/- mice showed a reduction in recognition memory as revealed by novel object recognition test. Since memory changes and stress related behavioural changes are all closely related to the hippocampus function we further analyzed the changes of dendrites and synapses of hippocampal neurons as well as expression levels of some proteins closely related to synaptic function. bc004004-/- mice exhibited decreased dendritic lengths and increased amount of immature spines, as well as altered expression pattern of synaptic related proteins including GluN2A, synaptophysin and BDNF in the hippocampus. Those findings suggest that BRAP homologous protein may have a protective effect on the behavioural response to stress via regulating dendritic spine formation and synaptic plasticity in the hippocampus.


Assuntos
Bombesina , Espinhas Dendríticas , Hipocampo , Plasticidade Neuronal , Receptores da Bombesina , Estresse Psicológico , Animais , Camundongos , Bombesina/genética , Bombesina/metabolismo , Doença Crônica , Espinhas Dendríticas/genética , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/patologia , Depressão/genética , Depressão/metabolismo , Depressão/patologia , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/patologia , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Receptores da Bombesina/genética , Receptores da Bombesina/metabolismo , Estresse Psicológico/genética , Estresse Psicológico/metabolismo , Estresse Psicológico/patologia
3.
J Nat Prod ; 82(9): 2460-2469, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31432669

RESUMO

Three new natural products (1-3), including two butenolide derivatives (1 and 2) and one dihydroquinolone derivative (3), together with nine known natural products were isolated from a marine-derived strain of the fungus Metarhizium marquandii. The structures of the new compounds were unambiguously deduced by spectroscopic means including HRESIMS and 1D/2D NMR spectroscopy, ECD, VCD, OR measurements, and calculations. The absolute configuration of marqualide (1) was determined by a combination of modified Mosher's method with TDDFT-ECD calculations at different levels, which revealed the importance of intramolecular hydrogen bonding in determining the ECD features. The (3R,4R) absolute configuration of aflaquinolone I (3), determined by OR, ECD, and VCD calculations, was found to be opposite of the (3S,4S) absolute configuration of the related aflaquinolones A-G, suggesting that the fungus M. marquandii produces aflaquinolone I with a different configuration (chiral switching). The absolute configuration of the known natural product terrestric acid hydrate (4) was likewise determined for the first time in this study. TDDFT-ECD calculations allowed determination of the absolute configuration of its chirality center remote from the stereogenic unsaturated γ-lactone chromophore. ECD calculations aided by solvent models revealed the importance of intramolecular hydrogen bond networks in stabilizing conformers and determining relationships between ECD transitions and absolute configurations.


Assuntos
Alcaloides/isolamento & purificação , Biologia Marinha , Metarhizium/química , Policetídeos/isolamento & purificação , Quinolonas/isolamento & purificação , Alcaloides/farmacologia , Animais , Antibacterianos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Metarhizium/metabolismo , Camundongos , Estrutura Molecular , Policetídeos/farmacologia , Quinolonas/farmacologia , Análise Espectral/métodos
4.
J Nat Prod ; 81(11): 2392-2398, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30343566

RESUMO

The first members of a new alkaloid class, chaetolines A (1) and B (2), which feature a pyrano[3,2- f]isoquinoline core structure, were obtained from a crude extract of the fungal endophyte Chaetomium sp. after cultivation in the presence of autoclaved Pseudomonas aeruginosa. The structures of the new compounds, including the absolute configuration of the major stereoisomer, were determined through detailed analysis of HRESIMS, 1D/2D NMR, and calculation of ECD data. The possible biosynthetic origin of the unprecedented scaffold of 1 and 2 is proposed. The current study provides further evidence for mixed fermentation as a powerful tool to induce the accumulation of cryptic fungal natural products even in the absence of viable bacterial cells.


Assuntos
Produtos Biológicos/isolamento & purificação , Chaetomium/química , Pseudomonas aeruginosa/química , Animais , Produtos Biológicos/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Isomerismo , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular
5.
Mar Drugs ; 15(11)2017 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-29137125

RESUMO

Three new 2-methoxy acetylenic acids (1-3) and a known derivative (4), in addition to three new natural pyrazole alkaloids (5-7) were isolated from an Indonesian marine sponge of the genus Cinachyrella. Compounds 5 and 6 have previously been reported as synthetic compounds. The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectroscopy as well as by mass spectrometric data. The absolute configuration of the new acetylenic acid derivatives (1-3) was established by ECD spectroscopy. All isolated compounds were evaluated for their cytotoxicity against L5178Y mouse lymphoma cells. Compounds 1-4 exhibited strong activity with an IC50 value of 0.3 µM. A plausible biosynthetic pathway for the pyrazole metabolites 5-7 is proposed.


Assuntos
Alcaloides/química , Alcinos/química , Ácidos Graxos Insaturados/química , Poríferos/química , Pirazóis/química , Alcaloides/farmacologia , Alcinos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Vias Biossintéticas/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Ácidos Graxos Insaturados/farmacologia , Indonésia , Linfoma/tratamento farmacológico , Camundongos , Pirazóis/farmacologia
6.
J Cell Biochem ; 117(5): 1069-77, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26460487

RESUMO

Our previous studies provided evidence that bombesin receptor-activated protein (BRAP), encoded by C6ORF89, is widely expressed in human airway epithelial cells and may play a role in the stress response of lung epithelia. In this study, we demonstrated that BRAP has a regulatory effect on NF-κB transcriptional activity in cultured human bronchial epithelial cells (HBECs). BRAP overexpression by gene transfer inhibited both basal and inducible NF-κB transcriptional activity in HBECs, whereas BRAP knockdown had the opposite effect. BRAP was shown to regulate NF-κB activity by enhancing histone deacetylase (HDAC) activity. In addition, BRAP might increase HDAC activity that leads to NF-κB activation via its putative C-terminal domain. Our study suggests that the BRAP protein is an important regulator of immune and inflammatory responses in the human airway epithelium.


Assuntos
Células Epiteliais/metabolismo , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/metabolismo , NF-kappa B/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Western Blotting , Brônquios/citologia , Linhagem Celular , Células HEK293 , Humanos , Interleucina-8/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos Endogâmicos BALB C , Microscopia Confocal , Oxidantes Fotoquímicos/farmacologia , Ozônio/farmacologia , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/genética
7.
Mar Drugs ; 13(5): 3061-71, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25988522

RESUMO

Hemibastadin derivatives, including the synthetically-derived 5,5'-dibromohemibastadin-1 (DBHB), are potent inhibitors of blue mussel phenoloxidase (PO), which is a key enzyme involved in the firm attachment of this invertebrate to substrates and, thus, a promising molecular target for anti-fouling research. For a systematic investigation of the enzyme inhibitory activity of hemibastadin derivatives, we have synthesized nine new congeners, which feature structural variations of the DBHB core structure. These structural modifications include, e.g., different halogen substituents present at the aromatic rings, different amine moieties linked to the (E)-2-(hydroxyimino)-3-(4-hydroxyphenyl)propionic acid, the presence of free vs. substituted aromatic hydroxyl groups and a free vs. methylated oxime group. All compounds were tested for their inhibitory activity towards the target enzyme in vitro, and IC50 values were calculated. Derivatives, which structurally closely resemble sponge-derived hemibastadins, revealed superior enzyme inhibitory properties vs. congeners featuring structural moieties that are absent in the respective natural products. This study suggests that natural selection has yielded structurally-optimized antifouling compounds.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/metabolismo , Mytilus edulis/efeitos dos fármacos , Mytilus edulis/metabolismo , Poríferos/química , Poríferos/metabolismo , Animais , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Relação Estrutura-Atividade
8.
J Clin Med ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38592187

RESUMO

(1) Background: Irritable bowel syndrome (IBS) is a highly prevalent disorder of gut-brain interaction (DGBI) that is known to reduce the quality of life and raise healthcare costs. The aim of this study was to describe the epidemiology of IBS in a large multiracial academic safety-net hospital. (2) Methods: An electronic query was performed using ICD-9 codes to identify 740 IBS outpatients seen at the Boston Medical Center (BMC) between 1 January 2005 and 30 September 2007. Demographic data were collected from electronic medical records. Bivariate analyses using chi-square tests and ANOVA were used to calculate the significance of categorical and continuous dependent variables, respectively. (3) Results: Compared with the general BMC outpatient population, the IBS cohort consisted of significantly higher proportions of White and Asian patients and lower proportions of Black and Hispanic patients (p < 0.0001). White and Asian patients predominantly had private insurance, while Black and Hispanic patients mostly had government/state-funded or no insurance (p < 0.0001). The IBS subgroup frequencies were similar across racial groups; however, Hispanic patients had IBS with constipation (32%, p < 0.02) more often compared to non-Hispanic patients. (4) Conclusions: Significant differences were found across the racial groups studied in this large outpatient IBS cohort. These findings are likely attributed to racial and socioeconomic disparities in healthcare access and utilization.

9.
J Clin Med ; 13(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38592303

RESUMO

Introduction: Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction (DGBI), and associated co-morbidities worsen quality of life. Research concerning IBS co-morbidities in different racial/ethnic groups is very sparse. This study aimed to determine the prevalence rates of co-morbidities and possible differences in a multiracial/ethnic IBS cohort. Methods: Based on ICD-9-coded IBS diagnosis, 740 outpatients (≥18 years) were included in this retrospective study at Boston Medical Center. Demographics and ICD-9-coded co-morbidities were extracted from electronic records. Descriptive statistics and multiple logistic regression were used for data analyses. Results: The most prevalent co-morbidities in this IBS cohort included gastroesophageal reflux disorder (GERD) (30%), depression (27%), anxiety (23%), (chronic obstructive pulmonary disease) COPD/asthma (16%), and obesity (10%). GERD was more prevalent in Hispanics and Blacks (p = 0.0005), and non-ulcer dyspepsia (NUD) was more prevalent in Blacks and Asians (p = 0.003). Higher rates of diabetes mellitus type 2 (DMT2) (p = 0.0003) and depression (p = 0.03), but not anxiety (p = 0.9), were present in Blacks and Hispanics. GERD was significantly associated with Hispanics (p = 0.003), dependent on age, overweight, and obesity. NUD was significantly associated with Blacks (p = 0.01) and Asians (p = 0.006), independent of sex, age, and BMI. Cancer of the thyroid, ovaries, and testis occurred at a five-fold higher rate than expected. Conclusions: Significant racial/ethnic differences exist for IBS co-morbidities in this study cohort, including depression, DMT2, GERD, and NUD. Certain cancers were found to be more frequent in this IBS sample as compared with the general population.

10.
J Cell Biochem ; 114(1): 238-44, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22930588

RESUMO

Bombesin receptor activated protein (BRAP) was identified in a bacterial two-hybrid screen for proteins interacting with bombesin receptor subtype-3 (BRS-3). We found that BRAP is widely expressed in the airway epithelium of human lungs and may play a role during the stress response of lung epithelium. In this work, we explored the potential roles of BRAP in the antigen presenting function of human bronchial epithelial cells (HBECs). Overexpression of a BRAP recombinant protein in a human bronchial epithelial cell line resulted in a reduction of FITC-OVA uptake by HBECs, which indicated that the antigen uptake ability is inhibited. The analysis of the protein expression of surface molecules including B7 homologs and the major histocompactability complex (MHC) class II molecules showed that the expression levels of HLA-DR and B7DC increased while the levels of B7-H1 and B7.2 decreased. Since those surface molecules are all related to antigen presenting process, the altered expression pattern of those molecules provides further evidence showing that BRAP overexpression leads to a change in antigen presenting function of HBECs. Moreover, overexpression of BRAP in HBECs caused a decrease of co-cultured lymphocytes proliferation and a changed pattern of cytokines produced by lymphocytes in the presence of FITC-OVA, which indicated that changes in the maturation pattern and functions of co-cultured lymphocytes were induced by BRAP overexpression. Overall, our results suggested that overexpression of BRAP may play a role during the antigen presenting process of bronchial epithelium by inhibiting the antigen uptake ability of bronchial epithelial cells.


Assuntos
Apresentação de Antígeno , Brônquios/imunologia , Células Epiteliais/imunologia , Linfócitos/imunologia , Mucosa Respiratória/imunologia , Ubiquitina-Proteína Ligases/genética , Antígenos B7/genética , Antígenos B7/imunologia , Brônquios/citologia , Brônquios/metabolismo , Comunicação Celular , Linhagem Celular Transformada , Técnicas de Cocultura , Endocitose , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Fluoresceína-5-Isotiocianato , Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Ativação Linfocitária , Linfócitos/citologia , Linfócitos/metabolismo , Ovalbumina/imunologia , Ovalbumina/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Ubiquitina-Proteína Ligases/imunologia
11.
J Clin Med ; 12(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36835815

RESUMO

Pancreatic neuroendocrine tumors, or pNETs, represent a rare and clinically heterogenous subset of pancreatic neoplasms. One such pNET, the insulinoma, is found to be malignant in just 4% of all insulinomas. Due to the exceedingly uncommon occurrence of these tumors, there is controversy regarding the optimal evidence-based management for these patients. We therefore report on a 70-year-old male patient admitted with 3 months of episodic confusion with concurrent hypoglycemia. The patient was found to have inappropriately elevated endogenous insulin levels during these episodes, and somatostatin-receptor subtype 2 selective imaging revealed a pancreatic mass metastatic to local lymph nodes, spleen, and the liver. Fine needle aspiration of pancreatic and liver lesions confirmed the diagnosis of a low grade pancreatic neuroendocrine tumor. Molecular analysis of tumor tissue revealed a novel mutational profile consistent with pNET. The patient was initiated on octreotide therapy. However, treatment with octreotide alone demonstrated limited efficacy in controlling the patient's symptoms, prompting consideration of other therapies.

12.
J Clin Med ; 12(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37048642

RESUMO

Irritable Bowel Syndrome (IBS) is a functional disorder of the gastrointestinal tract characterized by abdominal pain and altered bowel habits. It has a prevalence of 10 to 25% in the United States and has a high disease burden, as evidenced by reduced quality of life, decreased work productivity and increased healthcare utilization and costs. IBS has been associated with several intra-intestinal and extra-intestinal conditions, including psychiatric comorbidities. Although the pathophysiology of IBS has not been fully elucidated, it involves dysregulation of communication between the brain and gut (brain-gut axis) which is associated with alterations in intestinal motility, gut permeability, visceral hypersensitivity and gut microbiota composition. The purpose of this article is to review the role the gut microbiota plays in the pathophysiology of IBS, understand factors that affect the gut microbiome and explore the microbiome as a target of treatment.

13.
FEBS Lett ; 597(21): 2626-2642, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37715941

RESUMO

Both bombesin receptor-activated protein (BRAP) and its mouse homolog have been found to be expressed in bronchial epithelia but with unclear functions. Using electron microscopy combined with histological assays, we found that BRAP homolog deficiency in mice led to abnormal tracheal cilia. Rab-3A-interacting protein (Rabin8), a protein that might play a role in cilia development, was screened by yeast two-hybrid and further verified to have interaction with human BRAP by co-immunoprecipitation and pulldown assays. The expression levels of Rabin8, together with acetylated α-tubulin, a marker of cilia, were either downregulated by knockdown of BRAP or upregulated by overexpression of BRAP in cultured immortalized human bronchial epithelial cells. These results reveal a role for BRAP in airway cilia formation.


Assuntos
Cílios , Receptores da Bombesina , Animais , Humanos , Camundongos , Proteínas de Transporte/metabolismo , Cílios/genética , Cílios/metabolismo , Camundongos Knockout , Proteínas/metabolismo , Receptores da Bombesina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
14.
Life Sci Alliance ; 5(11)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35820707

RESUMO

Bombesin receptor-activated protein (BRAP) was found to express in the interstitial cells of human fibrotic lungs with unknown function. Its homologous protein, encoded by BC004004 gene, was also present in mouse lung tissues. We used BC004004 -/- mice which lack BRAP homologous protein expression to establish a bleomycin-induced lung fibrotic model. After bleomycin treatment, BC004004 -/- mice exhibited attenuation of pulmonary injury and less pulmonary fibrosis. Fibroblasts from BC004004 -/- mice proliferated at a lower rate and produced less collagen. Autophagy-related gene 5 (ATG5) was identified as a partner interacting with human BRAP. Lacking BRAP homologous protein led to enhanced autophagy activity in mouse lung tissues as well as in isolated lung fibroblasts, indicating a negative regulatory role of this protein in autophagy via interaction with ATG5. Enhanced autophagy process in fibroblasts due to lack of BRAP homologous protein might contribute to the resistance of BC004004 -/- mice to pulmonary fibrosis.


Assuntos
Bleomicina , Fibrose Pulmonar , Animais , Bleomicina/efeitos adversos , Bleomicina/metabolismo , Bombesina/efeitos adversos , Bombesina/metabolismo , Humanos , Pulmão/metabolismo , Camundongos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Receptores da Bombesina/genética , Receptores da Bombesina/metabolismo
15.
Biochem Biophys Res Commun ; 416(3-4): 397-402, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22120630

RESUMO

A number of cyclohexenyl chalcone Diels-Alder natural products possess promising biological properties including strong cytotoxicity in various human cancer cells. Herein, we show that natural products in this class including panduratin A and nicolaioidesin C inhibit cysteine cathepsins as indicated by protease profiling assays and cell-free cathepsin L enzyme assays. Owing to the critical roles of cathepsins in the biology of human tumor progression, invasion, and metastasis, these findings should pave the way for development of novel antitumor agents for use in clinical settings.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Catepsinas/antagonistas & inibidores , Chalcona/análogos & derivados , Cicloexanos/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Neoplasias da Próstata/enzimologia , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Produtos Biológicos/síntese química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Chalcona/síntese química , Chalcona/farmacologia , Chalconas/síntese química , Chalconas/farmacologia , Cicloexanos/síntese química , Cisteína Endopeptidases/metabolismo , Humanos , Masculino
16.
Opt Express ; 18(1): 72-8, 2010 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-20173824

RESUMO

Orbital angular momentum (OAM) of a helical beam is of great interests in the high density optical communication due to its infinite number of eigen-states. In this paper, an experimental setup is realized to the information encoding and decoding on the OAM eigen-states. A hologram designed by the iterative method is used to generate the helical beams, and a Michelson interferometer with two Porro prisms is used for the superposition of two helical beams. The experimental results of the collinear superposition of helical beams and their OAM eigen-states detection are presented.


Assuntos
Interferometria/instrumentação , Dispositivos Ópticos , Refratometria/instrumentação , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
17.
Opt Express ; 16(10): 7091-101, 2008 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-18545413

RESUMO

Orbital angular momentum (OAM) of laser beams has potential application in free space optical communication, but it is sensitive against pointing instabilities of the beam, i.e. shift (lateral displacement) and tilt (deflection of the beam). This work proposes a method to correct the distorted OAM spectrum by using the mean square value of the orbital angular momentum as an indicator. Qualitative analysis is given, and the numerical simulation is carried out for demonstration. The results show that the mean square value can be used to determine the beam axis of the superimposed helical beams. The initial OAM spectrum can be recovered.

18.
Inflamm Bowel Dis ; 24(2): 380-386, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29361083

RESUMO

Background: Studies have demonstrated an association between anti-TNF/immunomodulator agents used in inflammatory bowel disease (IBD) and impaired hepatitis B virus (HBV) vaccine immunogenicity, but little data exist on whether specific medication types affect protective HBsAb titers. Our aim was to analyze this association. Methods: This is a retrospective cohort study. Inclusion criteria: age ≥18, diagnosis of Crohn's disease (CD) or ulcerative colitis (UC), previous HBV vaccination series and/or ≥1 positive HBsAb, and record of IBD therapy in 6 months before titer level. Patients were stratified based upon medication exposures: anti-TNF, immunomodulator, combination anti-TNF and immunomodulatory, and a reference arm. Titer levels following vaccination and specific medication types given in the 6 months before titer were recorded. Seroprotection was defined as HBsAb ≥10 IU/l and ≥100 IU/l. Results: The study cohort (N = 391) was 70.8% white, 51.4% female and 64.2% had CD and 35.8% had UC. The mean age was 45.8 years. A significantly lower percentage of patients exposed to anti-TNF, immunomodulator or dual therapy had titers ≥10 (P < 0.01). Regarding specific medications, only patients exposed to infliximab (P < 0.01) were less likely to have titer levels ≥10, after controlling for other medication exposures, age at titer level, and interval time between vaccination/titer level. This was not found for patients exposed to adalimumab, methotrexate, 6-mercaptopurine, or azathioprine. Conclusions: Patients exposed to infliximab were significantly less likely to have protective HBsAb titer levels following vaccination, a trend not seen in patients on adalimumab. Efforts to vaccinate IBD patients against HBV before use of immunomodulators and anti-TNFs, infliximab specifically, and screen periodically thereafter must be reinforced.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/tratamento farmacológico , Infliximab/uso terapêutico , Formação de Anticorpos , Feminino , Vírus da Hepatite B , Humanos , Imunogenicidade da Vacina , Fatores Imunológicos/uso terapêutico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Fator de Necrose Tumoral alfa/antagonistas & inibidores
19.
Mar Biotechnol (NY) ; 9(6): 776-85, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17713818

RESUMO

Eighteen brominated sponge-derived metabolites and synthetic analogues were analyzed for antilarval settlement of Balanus improvisus. Only compounds exhibiting oxime substituents including bastadin-3 (4), -4 (1), -9 (2), and -16 (3), hemibastadin-1 (6), aplysamine-2 (5), and psammaplin A (10) turned out to inhibit larval settling at 1 to 10 microM. Analogues of hemibastadin-1 (6) were synthesized and tested for structure activity studies. Debromohemibastadin-1 (8) inhibited settling of B. improvisus, albeit at lower concentrations than hemibastadin-1 (6). Both 6 and 8 also induced cyprid mortality. 5,5'-dibromohemibastadin-1 (7) proved to be nontoxic, but settlement inhibition was observed at 10 microM. Tyrosinyltyramine (9), lacking the oxime function, was not antifouling active and was non-toxic at 100 microM. Hemibastadin-1 (6) and the synthetic products showed no general toxicity when tested against brine shrimp larvae. In contrast to the lipophilic psammaplin A (10), the hydrophilic sulfated psammaplin A derivative (11) showed no antifouling activity even though it contains an oxime group. We therefore hypothesize that the compound needs to cross membranes (probably by diffusion) and that the target for psammaplin A lies intracellularly.


Assuntos
Biologia Marinha , Poríferos/química , Thoracica/efeitos dos fármacos , Tirosina/toxicidade , Animais , Artemia/efeitos dos fármacos , Larva/efeitos dos fármacos , Oximas/química , Oximas/toxicidade , Éteres Fenílicos/química , Éteres Fenílicos/toxicidade , Thoracica/fisiologia , Tirosina/análogos & derivados , Tirosina/química , Tirosina/metabolismo
20.
Cancer Res ; 65(21): 9934-42, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16267018

RESUMO

Our previous studies indicate that the activation of mitogen-activated protein kinase (MAPK) pathway is involved in bombesin-induced cell proliferation in prostate cancer cells. Cyclin D1 is a critical regulator involved in cell cycle progression through the G1 phase into the S phase, thereby contributing to cell proliferation. Mostly, mitogen-stimulated expression of cyclin D1 is attributed to the extracellular signal-regulated kinase (ERK) activation. Here, we found that bombesin induced human cyclin D1 expression on both mRNA and protein levels in DU-145 prostate cancer cells. Mutational analyses showed that bombesin-enhanced cyclin D1 transcription required the binding of nuclear proteins to the -143 to -105 region of the human cyclin D1 promoter, which contains binding sites for transcription factors Sp-1 and early growth response protein (Egr-1). Do novo protein synthesis was requisite for bombesin-induced cyclin D1 expression. Further studies showed Egr-1 was induced upon bombesin stimulation. The induction of Egr-1 expression and its binding to the cyclin D1 promoter were essential for bombesin-enhanced cyclin D1 transcription. Inhibition of MAPK pathway with either the MEK1 inhibitor PD98059 or a dominant-negative Ras mutant, RasN17, abolished bombesin-induced cyclin D1 activation. Taken together, bombesin-induced cyclin D1 expression in prostate cancer cells is mediated by Egr-1 activation and the interaction of Egr-1 with the Egr-1/Sp1 motif of the cyclin D1 promoter through the activation of MAPK pathway. These findings represent a novel mechanism of bombesin-dependent stimulation of mitogenesis by regulating directly the cell cycle in prostate cancer.


Assuntos
Bombesina/farmacologia , Ciclina D1/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Ciclina D1/genética , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ligação Proteica , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ativação Transcricional , Transfecção
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