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1.
Opt Lett ; 48(4): 1020-1023, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791000

RESUMO

We present a high-performance laser frequency stabilization method using modulation transfer spectroscopy (MTS) on the rubidium 87D2 transition line. A substantial improvement of the laser frequency stability was achieved by searching for the optimal diameter and intensity settings of the probe and pump beam. The frequency instability measured from the beat frequency of two locked external cavity diode lasers (ECDLs) reached a short-term stability of 4.5×10-14/τ and did not exceed 2 × 10-12 until 105 s, which is the best performance reported thus far with a D2 transition. The long-term stability is limited by the offset fluctuations of the baseline induced by the residual amplitude modulation (RAM), which can be further improved by reducing the current temperature variation of about 0.2 K by means of temperature stabilization or through a further reduction of the RAM.

2.
Mar Drugs ; 21(9)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37755104

RESUMO

Benign prostatic hyperplasia (BPH), characterized by the enlargement of the prostate gland and subsequent lower urinary tract symptoms, poses a significant health concern for aging men with increasing prevalence. Extensive efforts encompassing in vitro and in vivo models are underway to identify novel and effective agents for the management and treatment of BPH. Research endeavors are primarily channeled toward assessing the potential of compounds to inhibit cell proliferation, curb inflammation, and display anti-androgenic activity. Notably, through screening aimed at inhibiting 5-alpha reductase type 2 (5αR2) in human prostatic cells, two acyl compounds (1 and 2) were isolated from a bioactive fraction sourced from an association of marine sponges Poecillastra sp. and Jaspis sp. The complete structure of 1 was determined as (Z)-dec-3-enony (2S, 3S)-capreomycidine, ascertained by JBCA and ECD comparison. While the absolute configurations of 2 remained unassigned, it was identified as a linkage of a 2, 7S*-dihydoxy-9R*-methyloctadecanoyl group with the 2-amino position of a tramiprosate moiety referred to as homotaurine. Evaluation of both compounds encompassed the assessment of their inhibitory effects on key biomarkers (5αR2, AR, PSA, and PCNA) associated with BPH in testosterone propionate (TP)-activated LNCap and RWPE-1 cells.

3.
Opt Express ; 30(14): 25707-25717, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237095

RESUMO

Transporting cold atoms between interconnected vacuum chambers is an important technique for increasing the versatility of cold atom setups, particularly for those that couple atoms to photonic devices. In this report, we introduce a method where we are able to image the atoms at all points during transport via moving optical dipole trap. Cooled 87Rb atoms are transported ∼50 cm into an auxiliary vacuum chamber while being monitored with a moving-frame imaging system for which in-situ characterization of the atom transport is demonstrated. Precise positioning of the atoms near photonic devices is also tested across several tapered fibers showing an axial positioning resolution of ∼450 µm.

4.
Opt Express ; 29(22): 35623-35639, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34808993

RESUMO

We present a parameter set for obtaining the maximum number of atoms in a grating magneto-optical trap (gMOT) by employing a machine learning algorithm. In the multi-dimensional parameter space, which imposes a challenge for global optimization, the atom number is efficiently modeled via Bayesian optimization with the evaluation of the trap performance given by a Monte-Carlo simulation. Modeling gMOTs for six representative atomic species - 7Li, 23Na, 87Rb, 88Sr, 133Cs, 174Yb - allows us to discover that the optimal grating reflectivity is consistently higher than a simple estimation based on balanced optical molasses. Our algorithm also yields the optimal diffraction angle which is independent of the beam waist. The validity of the optimal parameter set for the case of 87Rb is experimentally verified using a set of grating chips with different reflectivities and diffraction angles.

5.
Mar Drugs ; 19(6)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073814

RESUMO

Biofilm formation by Staphylococcus aureus plays a critical role in the persistence of chronic infections due to its tolerance against antimicrobial agents. Here, we investigated the antibiofilm efficacy of six phorbaketals: phorbaketal A (1), phorbaketal A acetate (2), phorbaketal B (3), phorbaketal B acetate (4), phorbaketal C (5), and phorbaketal C acetate (6), isolated from the Korean marine sponge Phorbas sp. Of these six compounds, 3 and 5 were found to be effective inhibitors of biofilm formation by two S. aureus strains, which included a methicillin-resistant S. aureus. In addition, 3 also inhibited the production of staphyloxanthin, which protects microbes from reactive oxygen species generated by neutrophils and macrophages. Transcriptional analyses showed that 3 and 5 inhibited the expression of the biofilm-related hemolysin gene hla and the nuclease gene nuc1.


Assuntos
Antibacterianos/farmacologia , Poríferos/química , Sesterterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Proteínas de Bactérias/genética , Biofilmes/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genes Bacterianos , Sesterterpenos/isolamento & purificação , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Staphylococcus aureus/fisiologia , Xantofilas/metabolismo
6.
Sensors (Basel) ; 21(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671625

RESUMO

We report a chip-scale atomic magnetometer based on coherent population trapping, which can operate near zero magnetic field. By exploiting the asymmetric population among magnetic sublevels in the hyperfine ground state of cesium, we observe that the resonance signal acquires sensitivity to magnetic field in spite of degeneracy. A dispersive signal for magnetic field discrimination is obtained near-zero-field as well as for finite fields (tens of micro-tesla) in a chip-scale device of 0.94 cm3 volume. This shows that it can be readily used in low magnetic field environments, which have been inaccessible so far in miniaturized atomic magnetometers based on coherent population trapping. The measured noise floor of 300 pT/Hz1/2 at the zero-field condition is comparable to that of the conventional finite-field measurement obtained under the same conditions. This work suggests a way to implement integrated atomic magnetometers with a wide operating range.

7.
Nano Lett ; 20(6): 4188-4196, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32406688

RESUMO

Developing materials with remote controllability of macroscale ligand presentation can mimic extracellular matrix (ECM) remodeling to regulate cellular adhesion in vivo. Herein, we designed charged mobile nanoligands with superparamagnetic nanomaterials amine-functionalized and conjugated with polyethylene glycol linker and negatively charged RGD ligand. We coupled negatively a charged nanoligand to a positively charged substrate by optimizing electrostatic interactions to allow reversible planar movement. We demonstrate the imaging of both macroscale and in situ nanoscale nanoligand movement by magnetically attracting charged nanoligand to manipulate macroscale ligand density. We show that in situ magnetic control of attracting charged nanoligand facilitates stem cell adhesion, both in vitro and in vivo, with reversible control. Furthermore, we unravel that in situ magnetic attraction of charged nanoligand stimulates mechanosensing-mediated differentiation of stem cells. This remote controllability of ECM-mimicking reversible ligand variations is promising for regulating diverse reparative cellular processes in vivo.


Assuntos
Adesão Celular , Fenômenos Magnéticos , Oligopeptídeos , Células-Tronco , Diferenciação Celular , Matriz Extracelular
8.
Molecules ; 26(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070629

RESUMO

Densazalin, a polycyclic alkaloid, was isolated from the marine sponge Haliclona densaspicula collected in Korea. The complete structure of the compound was determined by spectroscopic methods, including 1D and 2D nuclear magnetic resonance techniques, high-resolution mass spectrometry, and comparison of the calculated and measured electronic circular dichroism spectra. Densazalin possesses a unique 5,11-diazatricyclo[7.3.1.02,7]tridecan-2,4,6-triene moiety, which is connected by two linear carbon chains. This compound was derived from the biogenetic precursor bis-1,3-dialkylpyridnium. Densazalin exhibited cytotoxic activity on two human tumor cell lines (AGS and HepG2) in the Cell Counting Kit-8 (CCK-8) bioassay, with IC50 values ranging from 15.5 to 18.4 µM.


Assuntos
Alcaloides/isolamento & purificação , Biologia Marinha , Poríferos/química , Alcaloides/química , Alcaloides/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Análise Espectral/métodos
9.
Asian-Australas J Anim Sci ; 33(1): 91-99, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31902185

RESUMO

OBJECTIVE: This study investigated the effects of oral administration of rumen-protected L-tryptophan (RPL-T) on duodenal starch digestion and gastrointestinal hormones (GIH) secretions using Hanwoo beef steers as the animal models. METHODS: Four steers (423±24 kg) fitted with ruminal and duodenal cannulas were employed in a crossover design replicated twice. Treatments were control (basal diet) and RPL-T (basal diet+191.1 mg/kg body weight [BW]) group. Blood and duodenal samples were collected to measure serum GIH levels and pancreatic α-amylase activity at day 0, 1, 3, and 5 (-30, 30, 90, 150, and 210 min) of the study. Samples from each segment of the gastrointestinal tract were collected via ruminal and duodenal cannulas and were used to determine soluble protein and the starch digestion rate at days 6 (-30, 180, 360, and 540 min) and 8 (-30, 90, 270, and 450 min) of the experiment. RESULTS: No significant difference in ruminal pH, NH3-N, and total volatile fatty acid including the levels of acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and the acetate-to-propionate ratio was observed between groups (p>0.05). Crude protein uptake was higher and feces starch content was lower in RPL-T group than the control group (p<0.05). The D-glucose contents of feces in RPL-T group decreased at day 5 compared to those in the control group (p<0.05), however, no change was found at day 0, 1, or 3 compared to the control group (p>0.05). Serum cholecystokinin (CCK), melatonin, duodenal pancreatic α-amylase activity, and starch digestion were significantly higher in RPL-T group than the control group (p<0.05). CONCLUSION: Taken together, oral administration of RPL-T at the rate of 191.1 mg/kg BW consistently increased CCK concentration, pancreatic α-amylase activity in duodenal fluids, and starch digestion rate in the small intestine and thus found to be beneficial.

10.
J Nat Prod ; 82(4): 1034-1039, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917280

RESUMO

Herein, we clarify the structure and relative configurations of two prorocentrolide analogues (1 and 2) isolated from the benthic marine dinoflagellate Prorocentrum lima. The results of NMR spectroscopy show that 1 is prorocentrolide substituted by a hydroxy group at C-4, while the newly isolated compound 2 can be thought of as 1 lacking one ether ring and having one extra double bond. The relative configurations of all stereogenic centers and the configurations of the double bonds in 1 and 2 were determined utilizing ROESY correlations and J-based configuration analysis. Furthermore, 2 was shown to exhibit cytotoxicity against HCT-116 and Neuro-2a cells (IC50 2.2 and 5.2 µM, respectively.


Assuntos
Dinoflagellida/química , Toxinas Marinhas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Toxinas Marinhas/química , Relação Estrutura-Atividade
11.
Appl Opt ; 58(10): 2481-2484, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045040

RESUMO

We report the optical phase-locking of two extended-cavity diode lasers with a frequency difference of 6.9 GHz by serrodyne modulation. The bandwidth of the phase-locking loop is extended up to 9.5 MHz. The residual phase noise of the two phase-locked lasers reaches -130 dBrad2/Hz in the offset frequency range of 1.5 kHz to 9 kHz and below -120 dBrad2/Hz in the range of 150 Hz to 350 kHz, respectively. It is expected that the sensitivity limit of atom interferometers will be enhanced when the phase-locked lasers are used.

12.
Mar Drugs ; 17(11)2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717394

RESUMO

The inflammatory bowel diseases (IBD) cause chronic inflammation of the gastrointestinal tract and include ulcerative colitis (UC) and Crohn's disease (CD). The prevalence of IBD has been increasing worldwide, and has sometimes led to irreversible impairment of gastrointestinal structure and function. In the present study, we successfully isolated a new phylloketal derivative, deacetylphylloketal (1) along with four known compounds from the sponge genus Phyllospongia. The anti-inflammatory properties of deacetylphylloketal (1) and phyllohemiketal A (2) were evaluated using an in vitro co-culture system that resembles the intestinal epithelial environment. A co-culture system was established that consisted of human epithelial Caco-2 cells and phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophage cells. The treatment of co-cultured THP-1 cells with compounds 1 or 2 significantly suppressed the production and/or gene expression of lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E2 (PGE2), Interleukin-6 (IL-6), IL-1ß and Tumor Necrosis Factor alpha (TNF-α). The expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 were down-regulated in response to inhibition of NF-kB translocation into the nucleus in cells. In addition, we observed that 1 and 2 markedly promoted the nuclear translocation of Nrf2 and subsequent increase in the expression of heme oxygernase (HO)-1. These findings suggest the potential use of sponge genus Phyllospongia and its metabolites as a pharmaceutical aid in the treatment of inflammation-related diseases including IBD.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Poríferos/química , Sesterterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Células CACO-2 , Linhagem Celular , Técnicas de Cocultura , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/patologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Sesterterpenos/isolamento & purificação
13.
Molecules ; 24(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540496

RESUMO

Crohn's disease (CD) and ulcerative colitis (UC), collectively referred to as inflammatory bowel disease (IBD), are autoimmune diseases characterized by chronic inflammation within the gastrointestinal tract. Debromohymenialdisine is an active pyrrole alkaloid that is well known to serve as a stable and effective inhibitor of Chk2. In the present study, we attempted to investigate the anti-inflammatory properties of (10Z)-debromohymenialdisine (1) isolated from marine sponge Stylissa species using an intestinal in vitro model with a transwell co-culture system. The treatment with 1 attenuated the production and gene expression of lipopolysaccharide (LPS)-induced Interleukin (IL)-6, IL-1ß, prostaglandin E2 (PGE2), and tumor necrosis factor-α in co-cultured THP-1 macrophages at a concentration range of 1-5 µM. The protein expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were down-regulated in response to the inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) translocation into the nucleus in cells. In addition, we observed that 1 markedly promoted the nuclear translocation of nuclear factor erythroid 2 related factor 2 (Nrf2) and subsequent increase of heme oxygenase-1 (HO-1) expression. These findings suggest the potential use of 1 as a pharmaceutical lead in the treatment of inflammation-related diseases including IBD.


Assuntos
Organismos Aquáticos/química , Azepinas/farmacologia , Colite Ulcerativa , Doença de Crohn , Intestinos/patologia , Poríferos/química , Pirróis/farmacologia , Animais , Azepinas/química , Células CACO-2 , Técnicas de Cocultura , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Dinoprostona/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Pirróis/química , Células THP-1
14.
J Nat Prod ; 80(5): 1688-1692, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28383915

RESUMO

Limaol (1), along with a dinophysistoxin 1 derivative and an okadaic acid (OA) derivative, was isolated from the large-scale cultivation of the benthic marine dinoflagellate Prorocentrum lima. The structure of 1 was determined by a combination of NMR spectroscopy and mass spectrometry and contained tetrahydropyran, 1,3,5,7-tetra(methylene)heptane, and octahydrospiro[pyran-2,2'-pyrano[3,2-b]pyran] moieties. The absolute configuration of 1 was completely elucidated on the basis of ROESY correlations, J-based configuration analysis, and modified Mosher's ester analysis. Limaol showed moderate cytotoxicity when compared to OA against three cancer cell lines.


Assuntos
Dinoflagellida/química , Toxinas Marinhas/química , Ácido Okadáico/química , Ácido Okadáico/isolamento & purificação , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Piranos/isolamento & purificação , Compostos de Espiro/isolamento & purificação , Compostos de Espiro/farmacologia , Animais , Linhagem Celular Tumoral , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácido Okadáico/farmacologia , Policetídeos/química , Piranos/química , Piranos/farmacologia , Compostos de Espiro/química
15.
Opt Express ; 24(25): 28815-28828, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27958525

RESUMO

We investigate Mie resonances of a diamond nano-resonator as a means to enhance the pumping and detection efficiency of shallow nitrogen-vacancy color centers. We show it is possible to tune a couple of high-order modes of a single resonator to each absorption and emission spectrum of the color center, and thereby the resonator plays a dual role of pump field concentration and emission field guiding. Furthermore superposition of the resonator field and the uncoupled near field results in even stronger pump intensity in the shallow top layer of the resonator. We also examine possible coupling between adjacent resonators when they form a periodic array. This approach allows us to achieve lower excitation power and higher signal intensity at local sites defined by resonators providing a way to enhance wide-field metrology in the sampled region of shallow color centers.

16.
J Sci Food Agric ; 94(9): 1835-43, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24288234

RESUMO

BACKGROUND: The effects of the individual variation among dairy cows on the synthesis of cis-9, trans-11 conjugated linoleic acid (CLA) are still not well characterised. Therefore, the protein expression profiles of isolated milk epithelial cells (MECs) were detected by two-dimensional electrophoresis and their correlation with the various proportion of cis-9, trans-11 CLA were evaluated. RESULTS: Although animals were offered the same diet, the proportion of cis-9, trans-11 CLA in group High (1.02 ± 0.10%) was twice as high as that in group Low (0.59 ± 0.14%) (P < 0.05). MECs with the characteristics of native epithelial cells were successfully isolated from the milk and these cells had no obvious RNA degradation or were hardly contaminated with leucocytes or blood red cells. Moreover, the protein expression pattern of cathelicidin 5 in isolated MECs was positive, whereas annexin I (confirmed by real-time polymerase chain reaction), ZW10 interactor and κ-casein were negatively related to the proportion of cis-9, trans-11 CLA in the milk fat. CONCLUSION: The varied individual content of cis-9, trans-11 CLA in cows may be associated with annexin I. These findings may provide some theoretical basis for studies concerning the effects of the individual variation among dairy cows of the synthesis of cis-9, trans-11 CLA. © 2013 Society of Chemical Industry.


Assuntos
Anexina A1/metabolismo , Gorduras na Dieta/metabolismo , Células Epiteliais/metabolismo , Ácidos Linoleicos Conjugados/metabolismo , Leite/metabolismo , Proteoma/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Caseínas/metabolismo , Bovinos , Dieta , Feminino , Humanos , Lactação , Leite/citologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Catelicidinas
17.
Protein Expr Purif ; 89(1): 44-50, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23459292

RESUMO

CYP3A4 is the most abundant cytochrome P450 in the human liver. The expression level of CYP3A4 when coexpressed with cytochrome b(5) (cyt b(5)) in Escherichia coli was 20-60% higher than that when it was expressed alone over an extended period (48-72 h). This time-dependent elevation in coexpression with cyt b(5) was a result of an increase in CYP3A4 mRNA half-life; no significant change in CYP3A4 degradation was seen in the bacterial protease fraction. These results suggest that the higher CYP3A4 levels observed upon coexpression with cyt b(5) primarily resulted from CYP3A4 mRNA stabilization by cyt b(5).


Assuntos
Citocromo P-450 CYP3A/biossíntese , Citocromos b5/biossíntese , Fígado/enzimologia , Oxirredução , Citocromo P-450 CYP3A/genética , Citocromos b5/genética , Escherichia coli , Regulação Bacteriana da Expressão Gênica , Humanos , Cinética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Org Lett ; 24(23): 4182-4186, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35658491

RESUMO

Ovataline (1), which is a polar metabolite containing a hexahydroquinoline moiety, was isolated from cultures of the marine dinoflagellate Ostreopsis cf. ovata. 1 was characterized as a zwitterionic compound with hexahydroquinoline and tetrahydropyran rings. The configurations of the chiral centers in 1 were established using ROESY correlations, J-based configurational and Mosher reaction analyses, and density functional theory calculations. 1 exhibited a 78% (1 µM) inhibition of type II 5α-reductase in testosterone propionate-induced RWPE-1 human prostatic cells.


Assuntos
Dinoflagellida , Policetídeos , Colestenona 5 alfa-Redutase/metabolismo , Humanos , Policetídeos/metabolismo
20.
Opt Express ; 19(18): 17453-61, 2011 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-21935111

RESUMO

578-nm yellow light with an output power of more than 10 mW was obtained using a waveguide periodically-poled-lithium-niobate crystal as a nonlinear medium for second harmonic generation, which is the highest output power at this wavelength using second harmonic generation of a solid state laser source without an enhancement ring cavity, to our knowledge. To achieve this result we made a high power 1156-nm external-cavity diode laser with the maximum output power of more than 250 mW. This system is expected to be an excellent alternative to the system using the sum-frequency generation with the advantage of simplicity and cost-effectiveness, and will be used as a clock laser of the ytterbium optical lattice clock with robust and reliable operation.

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