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1.
Opt Lett ; 48(23): 6275-6278, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039245

RESUMO

Photonic integrated circuits play a vital role in enabling terahertz (THz) applications that require multi-octave bandwidth. Prior research has been limited in bandwidth due to rectangular waveguide (WRs) interconnects, which can only support single octave at low loss. To overcome this fundamental limitation, we exploit the ultra-wideband (UWB) near-field coupling between planar waveguides and silicon (Si)-based subwavelength dielectric rod waveguides (DRWs) to interconnect THz bandwidth uni-traveling-carrier photodiodes (UTC-PDs) at 0.08-1.03 THz. In a proof-of-concept experiment, the on-chip integrated UTC-PDs demonstrate a UWB operation from 0.1 THz to 0.4 THz. Furthermore, by employing Si DRWs as probes, multi-octave device-under-test characterization of UTC-PDs integrated with UWB transition is enabled with only one DRW probe. The proposed UWB interconnect technology is distinct from previously used WR-based ground-signal-ground probes or quasi-optical free-space coupling since it can provide multi-octave bandwidth and enable on-chip THz circuit integration.

2.
Molecules ; 28(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836692

RESUMO

Inflammatory bowel disease (IBD) is a persistent, lifelong inflammation of the digestive system. Dextran sulfate sodium is commonly used to induce colitis in experimental animal models, which causes epithelial damage, intestinal inflammation, mucin depletion, and dysbiosis of the gut microbiota. Various prebiotics, polysaccharides, and polypeptides are used for IBD treatment. In this study, we used a murine model utilizing BALB/c mice, with 10 mice per group, to investigate the treatment effect of sea conch peptide hydrolysate (CPH) on DSS-induced colitis mice. Colitis was induced through the administration of 2.5% DSS in drinking water over a seven-days period. Furthermore, on the eighth day of the experiment, sea conch peptide hydrolysate (CPH) at low (100 mg/kg), medium (200 mg/kg), and high (400 mg/kg) doses, which were continued for 14 days, were assessed for medicinal purposes in DSS-induced colitis mice. Our results showed that CPH treatment significantly alleviated the severity and symptoms of colitis. The epithelial integrity and histological damage were improved. Intestinal inflammation and inflammatory cell infiltration were improved. Furthermore, the expression of pro-inflammatory cytokines was reduced, and intestinal barrier integrity was restored by elevating the tight junction proteins. Moreover, 16s RNA sequencing revealed dysbiosis of the gut microbiota was observed upon DSS treatment, which was reinstated after CPH treatment. An increased level of Firmicutes and Lactobacillus was observed in the treatment groups. Finally, our results suggest that CPH would be recommended as a functional food source and also have the potential to be used as a medicinal product for different gastrointestinal disorders.


Assuntos
Colite , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Camundongos , Animais , Disbiose/induzido quimicamente , Disbiose/tratamento farmacológico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Doenças Inflamatórias Intestinais/patologia , Citocinas/metabolismo , Inflamação/patologia , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Colo/metabolismo
3.
Opt Lett ; 42(19): 3872-3875, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957148

RESUMO

We report on an optical frequency comb with 14 nm (∼1.8 THz) spectral bandwidth at a -3 dB level that is generated using a passively mode-locked quantum-well laser in photonic integrated circuits fabricated through an InP generic photonic integration technology platform. This 21.5-GHz colliding-pulse mode-locked laser cavity is defined by on-chip reflectors incorporating intracavity phase modulators followed by an extracavity semiconductor optical amplifier as a booster amplifier. A 1.8-THz-wide optical comb spectrum is presented with an ultrafast pulse that is 0.35 ps wide. The radio frequency beat note has a 3-dB linewidth of 450 kHz and 35-dB SNR.

4.
Materials (Basel) ; 16(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37445118

RESUMO

Horizontal-axis wind turbines are the most popular wind machines in operation today. These turbines employ aerodynamic blades that may be oriented either upward or downward. HAWTs are the most common non-conventional source of energy generation. These turbine blades fail mostly due to fatigue, as a large centrifugal force acts on them at high rotational speeds. This study aims to increase a turbine's service life by improving the turbine blades' fatigue life. Predicting the fatigue life and the design of the turbine blade considers the maximum wind speed range. SolidWorks, a CAD program, is used to create a wind turbine blade utilizing NACA profile S814. The wind turbine blade's fatigue life is calculated using Morrow's equation. A turbine blade will eventually wear out due to several forces operating on it. Ansys software is used to analyze these stresses using the finite element method. The fatigue study of wind turbine blades is described in this research paper. To increase a turbine blade's fatigue life, this research study focuses on design optimization. Based on the foregoing characteristics, an improved turbine blade design with a longer fatigue life than the original one is intended in this study. The primary fatigue parameters are the length of a chord twist angle and blade length. The experimental data computed with the aid of a fatigue testing machine are also used to validate the numerical results, and it is found that they are very similar to one another. By creating the most effective turbine blades with the longest fatigue life, this research study can be developed further. The most effective turbine blades with the longest fatigue life can be designed to further this research investigation.

5.
Lab Chip ; 22(9): 1764-1778, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35244110

RESUMO

Sensing devices have shown tremendous potential for monitoring state-of-the-art organ chip devices. However, challenges like miniaturization while maintaining higher performance, longer operating times for continuous monitoring, and fabrication complexities limit their use. Herein simple, low-cost, and solution-processible inkjet dispenser printing of embedded electrochemical sensors for dissolved oxygen (DO) and reactive oxygen species (ROS) is proposed for monitoring developmental (initially normoxia) and induced hypoxia in a custom-developed gut bilayer microfluidic chip platform for 6 days. The DO sensors showed a high sensitivity of 31.1 nA L mg-1 with a limit of detection (LOD) of 0.67 mg L-1 within the 0-9 mg L-1 range, whereas the ROS sensor had a higher sensitivity of 1.44 nA µm-1 with a limit of detection of 1.7 µm within the 0-300 µm range. The dynamics of the barrier tight junctions are quantified with the help of an in-house developed trans-epithelial-endothelial electrical impedance (TEEI) sensor. Immunofluorescence staining was used to evaluate the expressions of HIF-1α and tight junction protein (TJP) ZO-1. This platform can also be used to enhance bioavailability assays, drug transport studies under an oxygen-controlled environment, and even other barrier organ models, as well as for various applications like toxicity testing, disease modeling and drug screening.


Assuntos
Hipóxia , Microfluídica , Avaliação Pré-Clínica de Medicamentos , Humanos , Oxigênio , Espécies Reativas de Oxigênio
6.
Animals (Basel) ; 11(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062790

RESUMO

The aim of the current study was to assess the effect of two different fortified feeds with different concentrations of two important medicinal plants (Withania coagulans and Zingiber officinale) on the mucosal immunity of Labeo rohita. After a dietary intervention, mucus was tested against five pathogenic bacteria (in-vitro), while experimental fish were tested against the ectoparasite (Lernaea) (in-vivo). Our results revealed that all fish groups fed with different concentrations (1, 1.5, and 2%) of Z. officinale had low molecular weight proteins and did not develop any significant signs of parasitic infection, with low mortality rate; whereas the groups that were fed with W. coagulans (particularly with 1% and 2%), including a control group, developed rapid signs of infection with high mortality rate. The highest hemagglutination titer value was recorded for the fish fed with 1% and 1.5% of Z. officinale. The lowest value was found for the fish fed with 2% of W. coagulans. The mucus of all fish of fortified groups was active and inhibited the growth of tested bacterial pathogens as compared to the control group. Further, Z. officinale groups showed greater efficacy against bacteria as compared to the W. coagulans groups. In conclusion, Z. officinale can be considered as a potential and functional ingredient in aquaculture feed. Furthermore, future studies should be conducted to investigate more details on the subject.

7.
Clin Exp Dent Res ; 7(3): 293-301, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33300289

RESUMO

OBJECTIVES: To determine the effects of systematic calcitonin administration on post-orthodontic relapse in rat model. MATERIAL AND METHODS: This experimental animal model involved 36 male Wister rats. The maxillary right first molars were moved mesially, using a modified orthodontic appliance delivered 50 gm, for 14 days, retained for 4 days and left to relapse for 10 days. The study group was divided into three subgroups in which a single injection of calcitonin (20 IU/Kg), three injections of calcitonin (20 IU/Kg), each every other day, and normal saline were administered subcutaneously after orthodontic tooth movement has finished. The relapse ratio, histomorphometric analysis including osteoblasts, osteoclasts numbers and bone area and immunohistochemical analysis including the expression of receptor activator of nuclear factor kappa Β (RANK), receptor activator of nuclear factor kappa Β ligand (RANKL) and osteoprotegerin (OPG) were measured and assessed. RESULTS: The relapse ratio was significantly reduced in the three-dose calcitonin group (28%) compared to the single dose calcitonin group (34%) and the control group (46%). This was accompanied by a nonsignificant increase in osteoblasts number and bone area in three-dose calcitonin group and a nonsignificant reduction in osteoclast number. However, the immune histochemical expression of RANK, RANKL and OPG did not show statistically significant difference at the end of relapse period. CONCLUSIONS: Systemic administration of three doses of calcitonin may minimize the relapse ratio in experimentally moved rat molars.


Assuntos
Remodelação Óssea , Ligante RANK , Animais , Calcitonina , Masculino , Ratos , Ratos Wistar , Recidiva
8.
Chem Biol Drug Des ; 97(4): 914-929, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33342040

RESUMO

Cancer is the leading cause of mortality in the world. The major therapies for cancer treatment are chemotherapy, surgery, and radiation therapy. All these therapies expensive, toxic and show resistance. The plant-derived compounds are considered safe, cost-effective and target cancer through different pathways. In these pathways include oxidative stress, mitochondrial dependent and independent, STAT3, NF-kB, MAPKs, cell cycle, and autophagy pathways. One of the new plants derived compounds is Polyphyllin VII (PPVII), which target cancer through different molecular mechanisms. In literature, there is a review gap of studies on PPVII; therefore in the current review, we summarized the available studies on PPVII to provide a base for future research.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Saponinas/farmacologia , Autofagia/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117610, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31606675

RESUMO

Vaspin is a protein present in human serum that can cause type-2 diabetes, obesity, and other cardiovascular diseases. We report fluorescent upconverting nanoparticles (UCNPs)-based lateral flow biosensor for ultrasensitive detection of Vaspin. A pair (primary and secondary) of cognate aptamers was used that has duo binding with Vaspin. UCNPs with a diameter of around 100 nm were used as a tag to label a detection probe (secondary aptamer). A primary aptamer (capture probe) was immobilized on the test zone. Sandwich type hybridization reactions among the conjugate probe, target Vaspin, and primary aptamer were performed on the lateral flow biosensor. In the presence of target Vaspin, UCNPs were captured on the test zone of the biosensor and the fluorescent intensity of the captured UCNPs was measured through a colorimetric app under NIR. Fluorescence intensity indicates the quantity of Vaspin present in the sample. A range of Vaspin concentration across 0.1-55 ng ml-1 with a Limit of detection (LOD) 39 pg ml-1 was tested through this UCNPs based LFSA with high sensitivity, reproducibility and repeatability, whereas it's actual range in human blood is from 0.1 to 7 ng ml-1. Therefore, this research provides a well-suited lateral flow strip with an ultrasensitive and low-cost approach for the early diagnosis of type-2 diabetes and this could be applied to any targets with a duo of aptamers generated.


Assuntos
Técnicas Biossensoriais/métodos , Análise Química do Sangue/métodos , Corantes Fluorescentes , Nanopartículas/química , Serpinas/análise , Aptâmeros de Nucleotídeos/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diagnóstico Precoce , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Humanos , Limite de Detecção , Ligação Proteica , Reprodutibilidade dos Testes , Serpinas/metabolismo
10.
Vet World ; 11(4): 431-436, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29805206

RESUMO

AIM: This study was designed to investigate the occurrence of serotypes of Listeria monocytogenes, an important food-borne pathogen, in gallbladder samples from cattle and sheep. MATERIALS AND METHODS: Three hundred samples were collected and screened for the presence of L. monocytogenes. The identification of the isolates was confirmed by API-Listeria system and by the presence of hemolysin (hyl) gene. The isolates were subjected to polymerase chain reaction-based serotype identification with d1 (division 1), d2 (division 2), glt, mama (mismatch amplification mutation assay), and flaA (flagellin protein) genes. RESULTS: A total of 8 (2.7%) L. monocytogenes were recovered from 6 (4.0%) samples of sheep and 2 (1.3%) samples of cattle. All isolates showed positive results with Hly primers. Four isolates carried d1 gene, did not possess glt gene and harbored mama gene. The serotypes of these isolates were identified as 4a or 4c. The other 4 isolates carried d2 gene, 3 of them were positive with the FlaA primers, and hence, determined to be a 1/2a or 3a serotype, and 1 isolate was determined to be 1/2c or 3c serotype. CONCLUSION: This study concluded that the presence of 1/2a serotype in gallbladder samples indicates public health risk through cross-contamination of meat at slaughterhouses.

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