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1.
Sensors (Basel) ; 22(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35891022

RESUMO

The objective of this study is to design the hull-mounted sonar dome of a ship. The goal is to reduce the ship total resistance and improve the flow field around the sonar dome for the ship design speed. OpenFOAM 6 was applied to analyze the viscous flow around the ship bow and then optimize the sonar dome geometry. The length, width and depth of the original geometry were maintained. Only the local geometry was fine-tuned considering the back slope and front tip by using Rhinoceros 6. The verification and validation was performed for the original hull form against towing tank resistance data. The grid independence was checked for the optimal design in different design stages. To ensure less influence on the interior equipment installation and to be able to re-use the non-steel dome part, the best resistance reduction is almost 2%. With a larger allowance of shape deformation, the maximal reduction could reach slightly higher than 3%. The flow field is improved for smaller flow separation and vortex, and less fluid nose in sonar detection is expected. The main reason of the resistance reduction is the decrease of the pressure component. In conclusion, a sonar dome design procedure is proposed, and an optimal geometry is suggested.


Assuntos
Navios , Som , Viscosidade
2.
ACS Appl Mater Interfaces ; 15(12): 16153-16161, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36802501

RESUMO

Layered transition metal dichalcogenides (TMDs) are two-dimensional materials exhibiting a variety of unique features with great potential for electronic and optoelectronic applications. The performance of devices fabricated with mono or few-layer TMD materials, nevertheless, is significantly affected by surface defects in the TMD materials. Recent efforts have been focused on delicate control of growth conditions to reduce the defect density, whereas the preparation of a defect-free surface remains challenging. Here, we show a counterintuitive approach to decrease surface defects on layered TMDs: a two-step process including Ar ion bombardment and subsequent annealing. With this approach, the defects, mainly Te vacancies, on the as-cleaved PtTe2 and PdTe2 surfaces were decreased by more than 99%, giving a defect density <1.0 × 1010 cm-2, which cannot be achieved solely with annealing. We also attempt to propose a mechanism behind the processes.

3.
J Poult Sci ; 59(3): 260-271, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35989696

RESUMO

The aim of this study was to evaluate the effects of B. subtilis-fermented products (BSFP) on growth performance, intestinal inflammatory gene expression, and cecal microbiota community in broilers challenged with dextran sulfate sodium (DSS) in a 14-day experiment. A total of 32, 1-day-old male broiler chickens (Ross 308), were randomly divided into four groups of eight birds per group and reared individually (n=8). The treatments consisted of a control diet without supplementation and DSS challenge, control diet plus 1.5% DSS, control diet plus 1 g/kg BSFP in combination with 1.5% DSS, and control diet plus 3 g/kg of BSFP in combination with 1.5% DSS. The results showed that BSFP supplementation (1 and 3 g/kg) partially improved body weight and average daily gain in broilers under DSS challenge. Relative to DSS treatment alone, BSFP supplementation dose-dependently increased the body weight of broilers at 7 days of age, with the average daily gain being at 1 to 7 days of age. BSFP supplementation (1 and 3 g/kg) alleviated intestinal inflammatory gene expression in broilers under DSS challenge. The richness and evenness of bacterial species in cecal digesta increased in a dose-dependent manner in the groups treated with BSFP (1 and 3 g/kg) in combination with DSS challenge, compared with the control group. Unweighted principal coordinate analysis indicated distinct clusters separating the group treated with 3 g/kg of BSFP in combination with DSS challenge from the other three groups. The abundance of short-chain fatty acid-producing bacteria (genus Ruminococcaceae_unclassified) increased and that of mucindegrading bacteria (genus Ruminococcus torques group) decreased in the cecal digesta of broilers fed 3 g/kg of BSFP, compared with the control group. In conclusion, BSFP supplementation dose-dependently improved growth performance, reduced gut inflammation, and regulated the cecal microbiota of broilers exposed to DSS challenge during the starter phase.

4.
Artigo em Inglês | MEDLINE | ID: mdl-19307173

RESUMO

The purpose of the present study was to investigate the effects of Gingyo-san (GGS), a traditional Chinese medical formula, on peripheral lymphocyte proliferation and serum antibody titers in chickens vaccinated against the infectious bursal disease (IBD) virus. Treatment groups were fed one of three doses of GGS in their diet (0.5%, 1.0% and 2.0%, w/w), and the IBD vaccine was administered at 1 and 3 weeks of age. At Weeks 8, 12 and 16, changes in serum IBD antibody titers were measured via the micro-method and T cell proliferation. In gene expression experiments, GGS-treated peripheral T lymphocytes were stimulated with concanavalin A (ConA) for 24 h. The mRNA expression of interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-4 (IL-4) and interleukin-12 (IL-12) was determined using a semi-quantitative RT-PCR assay. The results showed that a low dose of GGS could significantly raise the antibody titers. Medium and high doses of GGS enhanced IL-2 and IFN-γ production. GGS altered the expression of IL-4 and IL-12 in T lymphocytes. CD4(+) T lymphocyte development was also skewed towards the Th1 phenotype. GGS enhanced cell-mediated immunity and augmented the effects of IBD vaccination in strengthening subsequent anti-viral responses.

5.
Poult Sci ; 100(2): 875-886, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518141

RESUMO

In this study, the effects of Bacillus subtilis-fermented products on the growth performance and cecal microbiota of broilers were investigated in response to lipopolysaccharide (LPS) challenge. A total of 120 one-day-old male broiler chicks (Ross 308) were randomly assigned to 4 dietary treatments, with 5 replicate cages per treatment and 6 birds per cage. The dietary treatments comprised a basal diet as the control, basal diet plus 5 mg/kg of LPS, and basal diet plus 5 mg/kg of LPS in combination with 1 and 3 g/kg of B. subtilis-fermented products. The results indicated that B. subtilis-fermented product supplementation increased (linear, P < 0.05) the body weight of broilers relative to LPS treatment alone at 21 d of age. At 15 to 21 d and 1 to 21 d of age, B. subtilis-fermented product supplementation improved (linear, P < 0.05) the average daily gain in broilers compared with LPS challenge alone. The inflammation-associated gene expression was decreased (P < 0.05), and intestinal barrier-associated gene expression was increased (P < 0.05) in the small intestine of the group treated with 3 g/kg of B. subtilis-fermented products in combination with LPS challenge. In cecal microbiota analysis, the richness of bacterial species was lower (P < 0.05) in the groups treated with 1 and 3 g/kg of B. subtilis-fermented products in combination with LPS challenge than in the control group. Principal coordinates analysis indicated distinct clusters between the groups treated with LPS alone and B. subtilis-fermented products in combination with LPS challenge. The abundance of the genera Erysipelatoclostridium and Ruminococcaceae_unclassified in the cecal digesta decreased (P < 0.05) in broilers fed with B. subtilis-fermented products compared with the control group. The average abundance of the genera Bacteroides and Romboutsia in the cecal digesta was positively correlated with the body weight and average daily gain of broilers in response to LPS challenge. Furthermore, the average abundance of the genera Bacteroides and Romboutsia in the cecal digesta was positively correlated with the concentration of B. subtilis-fermented products under LPS challenge. These results demonstrate that B. subtilis-fermented products can improve the growth performance and modulate the gut microflora composition of broilers under immune stress.


Assuntos
Ração Animal , Bacillus subtilis/metabolismo , Ceco/microbiologia , Galinhas/crescimento & desenvolvimento , Lipopolissacarídeos/toxicidade , Ração Animal/análise , Animais , Galinhas/microbiologia , Dieta/veterinária , Suplementos Nutricionais , Fermentação , Masculino
6.
ACS Appl Mater Interfaces ; 11(1): 84-95, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30500151

RESUMO

Photodynamic therapy (PDT) is a noninvasive medical technology that has been applied in cancer treatment where it is accessible by direct or endoscope-assisted light irradiation. To lower phototoxicity and increase tissue penetration depth of light, great effort has been focused on developing new sensitizers that can utilize red or near-infrared (NIR) light for the past decades. Lanthanide-doped upconversion nanoparticles (UCNPs) have a unique property to transduce NIR excitation light to UV-vis emission efficiently. This property allows some low-cost, low-toxicity, commercially available visible light sensitizers, which originally are not suitable for deep tissue PDT, to be activated by NIR light and have been reported extensively in the past few years. However, some issues still remain in the UCNP-assisted PDT platform such as colloidal stability, photosensitizer loading efficiency, and accessibility for targeting ligand installation, despite some advances in this direction. In this study, we designed a facile phospholipid-coated UCNP method to generate a highly colloidally stable nanoplatform that can effectively load a series of visible light sensitizers in the lipid layers. The loading stability and singlet oxygen generation efficiency of this sensitizer-loaded lipid-coated UCNP platform were investigated. We also have demonstrated the enhanced cellular uptake efficiency and tumor cell selectivity of this lipid-coated UCNP platform by changing the lipid dopant. On the basis of the evidence of our results, the lipid-complexed UCNP nanoparticles could serve as an effective photosensitizer carrier for NIR light-mediated PDT.


Assuntos
Raios Infravermelhos , Lipídeos , Nanopartículas , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes , Oxigênio Singlete/metabolismo , Animais , Células HeLa , Humanos , Lipídeos/química , Lipídeos/farmacologia , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/metabolismo , Neoplasias/patologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Ratos
8.
Carbohydr Polym ; 138: 114-22, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26794744

RESUMO

Gentamicin (GM), one of the most commonly used aminoglycoside antibiotics, has been used for treating pneumonia; however, the applicability of GM is limited by its bioavailability and toxic side effects. This study used chitosan (CS)/fucoidan (F) nanoparticles (NPs) to develop a nanoformulation for pulmonary delivery of GM, presenting a biphasic release feature. The NPs exhibited a zero-order release of GM for the first 10h, followed by a sustained release of up to 72h, attaining a value of 99%. The GM-loaded CS/F NPs provide multiple antimicrobial capabilities against Klebsiella pneumoniae, including the CS and biphasic release of GM. Compared with the intravenous administration of free GM (0.5mg/kg), the intratracheal administration of GM-loaded CS/F NP (0.27mg/kg) presented a superior area under the concentration-time curve/minimum inhibitory concentration ratio, indicating the simultaneous improvement of antimicrobial efficacy and elimination of systemic toxicity. These results suggested that CS/F NPs are potential carriers in pulmonary delivery of GM for pneumonia treatment.


Assuntos
Antibacterianos/química , Quitosana/química , Portadores de Fármacos/química , Gentamicinas/química , Nanopartículas/química , Polissacarídeos/química , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Gentamicinas/farmacocinética , Gentamicinas/farmacologia , Meia-Vida , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Oncotarget ; 7(34): 55437-55448, 2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28874965

RESUMO

Recent studies have implicated the prorenin receptor (PRR) is associated with pancreatic tumorigenesis. We therefore investigated the role of PRR in pancreatic tumorigenesis and assessed whether PRR can serve as a target for imaging diagnosis at early stages of PDAC. Here we show that aberrant expression of PRR in premalignant PanIN lesions, and human PDAC samples, and PDAC cell lines, particularly in Panc-1 cells. Interestingly, PRR expression was positively associated with PDAC progression. Moreover, overexpression of human PRR resulted in increased cell proliferation and decreased apoptosis, while knockdown of human PRR caused decreased cell proliferation and enhanced apoptosis in pancreatic cancer cells. We also observed that overexpression of human PRR enhanced MAPK and PI3K/Akt signaling pathways in PDAC cells, while knockdown of human PRR suppressed both of pathways. The confocal imaging analysis showed that human PRR was highly expressed in Panc-1, ASPC, and Miapaca cells, whereas BXPC-3, and HPAC cells had a significantly lower fluorescent signals. Consistently, the single-photon emission computed tomography (SPET/CT) showed that the uptake of anti-PRR labelled with 125I was higher in Panc-1 and ASPC tumors-bearing mice after 96 hours injection. Importantly, tumors in pancreas of Pdx1-cre; LSL-KrasG12D mice had a significant increased PRR expression and accumulation of radioactivity at 96 h after injection. These data suggest that 125I-anti-PRR can detect the orthotopic tumors in Pdx1-cre; LSL-KrasG12D mice. Therefore, anti-PRR labelled with 125I is a promising radiotracer for imaging diagnosis at early stages of pancreatic cancer.


Assuntos
Carcinoma in Situ/diagnóstico , Carcinoma Ductal Pancreático/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Receptores de Superfície Celular/metabolismo , Animais , Apoptose , Carcinoma in Situ/diagnóstico por imagem , Carcinoma Ductal Pancreático/diagnóstico por imagem , Proliferação de Células , Humanos , Processamento de Imagem Assistida por Computador , Radioisótopos do Iodo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Pancreáticas/diagnóstico por imagem , Receptores de Superfície Celular/antagonistas & inibidores , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor de Pró-Renina
10.
Appl Radiat Isot ; 88: 89-93, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24447933

RESUMO

We have already synthesized a boron-containing polymeric micellar drug delivery system for boron neutron capture therapy (BNCT). The synthesized diblock copolymer, boron-terminated copolymers (Bpin-PLA-PEOz), consisted of biodegradable poly(D,l-lactide) (PLA) block and water-soluble polyelectrolyte poly(2-ethyl-2-oxazoline) (PEOz) block, and a cap of pinacol boronate ester (Bpin). In this study, we have demonstrated that synthesized Bpin-PLA-PEOz micelle has great potential to be boron drug delivery system with preliminary evaluation of biocompatibility and boron content.


Assuntos
Compostos de Boro/química , Compostos de Boro/toxicidade , Terapia por Captura de Nêutron de Boro/métodos , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/síntese química , Ácido Láctico/análogos & derivados , Polímeros/química , Polímeros/toxicidade , Implantes Absorvíveis , Compostos de Boro/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/toxicidade , Difusão , Desenho de Fármacos , Células HeLa , Humanos , Ácido Láctico/química , Ácido Láctico/toxicidade
11.
ACS Appl Mater Interfaces ; 6(10): 7198-203, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24766528

RESUMO

An efficient method for modifying the surface of detonation nanodiamonds (5 and 100 nm) with thiol groups (-SH) by using an organic chemistry strategy is presented herein. Thiolated nanodiamonds were characterized by spectroscopic techniques, and the atomic percentage of sulfur was analyzed by elemental analysis and X-ray photoelectron spectroscopy. The conjugation between thiolated nanodiamonds and gold nanoparticles was elucidated by transmission electron microscopy and UV-vis spectrometry. Moreover, the material did not show significant cytotoxicity to the human lung carcinoma cell line and may prospectively be applied in bioconjugated technology. The new method that we elucidated may significantly improve the approach to surface modification of detonation nanodiamonds and build up a new platform for the application of nanodiamonds.


Assuntos
Nanodiamantes/química , Compostos de Sulfidrila/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ouro/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Transmissão , Nanodiamantes/toxicidade , Tamanho da Partícula , Espectroscopia Fotoeletrônica
12.
Artigo em Inglês | MEDLINE | ID: mdl-24250714

RESUMO

The animals used in liver fibrosis studies must usually be sacrificed. Ultrasound has been demonstrated to have the ability to diagnose hepatic fibrosis and cirrhosis in experimental small-animal models. However, few studies have used high-frequency ultrasound (HFU, 40 MHz) to monitor changes in the rat liver and other hollow organs longitudinally. In this study, liver fibrosis was induced by administering dimethylnitrosamine (DMN) in SD rats, aged 8 weeks, for three consecutive days per week for up to 4 weeks. A Chinese herbal medicine Yi Guan Jian (YGJ) was orally administered (1.8 g/kg daily) to DMN-induced liver fibrosis rats for 2 weeks. Compared with the normal control rats, rats treated with DMN for either 2 weeks or 4 weeks had significantly lower body weights, liver indexes and elevation of hydroxyproline, GOT, and GPT contents. YGJ herbal treatment remarkably prevented rats from DMN-induced liver fibrosis. The HFU scoring results among the normal controls, 2-week DMN-treated rats, 4-week DMN-treated rats, and combined 2-week YGJ therapy with 4-week DMN-treated rats also reached statistical significance. Thus, HFU is an accurate tool for the longitudinal analysis of liver fibrosis progression in small-animal models, and the YGJ may be useful in reversing the development of hepatic fibrosis.

13.
J Ethnopharmacol ; 142(3): 811-8, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22706148

RESUMO

ETHNOPHARMACOLOGICAL EVIDENCE: Gexia-Zhuyu Tang (GZT), also called Gexiazhuyu decoction (GXZYD), is a traditional Chinese herbal medicine for chronic liver diseases such as cirrhosis and liver fibrosis. AIM OF THE STUDY: In this study, we have investigated the affects of GZT on a rat model of dimethylnitrosamine (DMN)-induced liver fibrosis. MATERIALS AND METHODS: In this study, the protective effects of GZT on DMN-induced liver fibrosis were measured using a rat model. Following 5 weeks of DMN-treatment (8 mg/kg, i.p., given 3 consecutive days each week), oral administration of GZT at 1.8 g/kg daily via oral gavage for 2weeks beginning at week 13. RESULTS: Both body and liver weights were significantly decreased. The reductions in body and liver weights corresponded with increasing liver damage severity. Furthermore, GZT-treatment remarkably decreased the levels of serum GOT (glutamate oxaloacetate transaminase) and GPT (glutamic pyruvic transaminase), and the mRNA expression levels of collagen alpha-1(I) and alpha-smooth muscle actin (alpha-SMA) in DMN-induced hepatic fibrosis. In addition, hepatic stellate cells (HSCs) play a major role in various types of liver fibrosis through initial myofibroblast transformation. The proliferation of HSCs was inhibited by GZT. Treatment with GZT also induced HSC apoptosis in a dose- and time-dependent manner. GZT treatment induced HSC apoptosis by facilitating Ca(2+) release from the mitochondria within 6h. Subsequently, caspases 3 and 12 were elevated by 72 h after treatment. CONCLUSIONS: Our studies indicate that GZT exhibited both hepatoprotective and antifibrogenic effects in DMN-induced hepatic injury. These findings suggest that GZT may be useful in preventing the development of hepatic fibrosis.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/prevenção & controle , Fitoterapia , Actinas/genética , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Caspase 12/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Dimetilnitrosamina , Medicamentos de Ervas Chinesas/farmacologia , Células Estreladas do Fígado/citologia , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/diagnóstico por imagem , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ultrassonografia
14.
J Ethnopharmacol ; 134(3): 953-60, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21333722

RESUMO

AIMS OF THE STUDY: Yi Guan Jian (YGJ) has long been employed clinically to treat liver fibrosis in traditional Chinese Medicine but the mechanism underlying the regulation has not been clarified in detail. The present investigation was designed to assess the involvement of the fibrosis pathway in dimethylnitrosamine (DMN)-induced liver fibrosis in rats. MATERIALS AND METHODS: Liver fibrosis was induced by DMN injection (10mg/kg, i.p., given three consecutive days each week) following 4 weeks. YGJ was oral administered (1.8 g/kg daily via gastrogavage for two weeks). Liver sample were subjected to histological and western blot studies. For evaluation of hepatic fibrosis-related factors, collagen α1-I, tissue inhibitor of metalloproteinase-1 (TIMP-1), and α-smooth muscle actin (α-SMA) mRNA and protein levels were analyzed. RESULTS: YGJ remarkably prevented body weight loss and DMN damage in the liver, and it inhibited the elevation of serum glutamate oxaloacetate transaminase (GOT), and glutamic pyruvic transaminase (GPT). Oral administration of YGJ extract significantly reduced the accumulation of collagen α1-I, TIMP-1, and α-SMA in liver tissues. CONCLUSIONS: Taken together, these findings indicate that the YGJ Chinese herb showed hepatoprotective and anti-fibrogenic effects against DMN-induced hepatic injury. Our data suggest that the YGJ may be useful in reversing the development of hepatic fibrosis.


Assuntos
Dimetilnitrosamina/toxicidade , Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática/tratamento farmacológico , Fígado/efeitos dos fármacos , Actinas/genética , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Sequência de Bases , Western Blotting , Colágeno Tipo I/genética , Primers do DNA , Medicamentos de Ervas Chinesas/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-1/genética
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