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1.
Medicine (Baltimore) ; 103(3): e36095, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38241526

RESUMEN

BACKGROUND: Impaired lower extremity motor function and knee pain are common concerns in patients with patellofemoral pain syndrome (PFPS). It is essential to plan therapeutic techniques to therapy PFPS. The objective of this study was to determine the effect of neuromuscular electrical stimulation (NMES) combined with functional training on pain, lower extremity function and muscle recruitment in patients with PFPS. METHODS: Twenty-four PFPS patients (male-13, female-11) were selected to conduct this study finally. Two groups were formed: the control group (n = 12) which included functional training only and the experimental group (n = 12) which functional training along with NMES-in both groups interventions were performed for 45 minutes/session, 3 days/weeks for 6 weeks. The functional training consisted of warm-up activities, strength training, balance training, and relaxation activities. All patients were evaluated with surface electromyography testing system for the root mean square and integrated electromyography of vastus medial oblique (VMO), vastus lateralis (VL), and VMO/VL ratio, visual analog scores (VAS) for pain, and Kujala functional score for knee joint function before and after 6 weeks. Normality was tested for all outcome variables using Shapiro-Wilk test. Nonparametric (Mann-Whitney U test and Wilcoxon signed-rank test) tests were used to analyze data. A 2-way analysis of variance with repeated measures (group*time) was applied to analyze the data. RESULTS: A significant increases (P < .001) root mean square and integrated electromyography of VMO, VMO/VL ratio, and Kujala score in both groups, For VAS scores, significant decreases was observed in both groups. When both groups were compared, greater improvement (P < .05) was observed in the experimental group in comparison the control group for both knee pain, lower extremity function and muscle recruitment. However, there was no difference in VL muscle recruitment between the 2 groups. CONCLUSIONS: Functional training and NMES combined with functional training are helpful to improve pain, knee function and muscle recruitment of PFPS patients. NMES combined with functional training was more effective compared to the control group. This may help clinical trialists to use different NMES to synchronize other interventions in future studies to enhance rehabilitation efficacy in PFPS patients through passive training versus active stimulation.


Asunto(s)
Músculo Esquelético , Síndrome de Dolor Patelofemoral , Humanos , Masculino , Femenino , Síndrome de Dolor Patelofemoral/terapia , Electromiografía/métodos , Dolor , Músculo Cuádriceps , Articulación de la Rodilla , Estimulación Eléctrica
2.
Porcine Health Manag ; 9(1): 24, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37221604

RESUMEN

BACKGROUND: Stress, herd transfer, and food changes experienced by nursery and fattening pigs can lead to reduced performance, reduced digestion and absorption, and impaired intestinal health. Given the role of essential oils in relieving stress and improving animal welfare, we hypothesized that essential oils may improve pig performance via promoting gut health and gut homeostasis laid by EOs supplementation during nursery continuously impacts performance in fattening pigs. RESULTS: A total of 100 piglets (Landrace × Large White; weighted 8.08 ± 0.34 kg, weaned at d 28) were randomly selected and divided into 2 treatments: (1) basal diet (Con); (2) basal diet supplement with 0.1% complex essential oils (CEO). The experiment period was 42 days. Then weaned piglets' growth performance and indications of intestinal health were assessed. Compared to the Con group, dietary supplemented CEO enhanced BW at 14 d (P < 0.05), and increased ADG during 1 ~ 14 d and 1 ~ 42 d (P < 0.05). Furthermore, CEO group had lower FCR during 1 ~ 42 d (P < 0.05). The CEO group also showed higher VH and VH:CD in duodenum and ileum (P < 0.05). Additionally, dietary CEO supplementation improved gut barrier function, as manifested by increased the mRNA expression of tight-junction protein and decreased serum DAO, ET and D-LA levels (P < 0.05). Finally, CEO supplementation alleviated gut inflammation, increased the activity of digestive enzymes. Importantly, piglets supplemented with CEOs during nursery also had better performance during fattening, suggesting that the establishment of intestinal health will also continuously affect subsequent digestion and absorption capacity. In short, dietary supplemented CEO improved performance and gut health via modulating increased intestine absorptive area, barrier integrity, digestive enzyme activity, and attenuating intestine inflammation. Meanwhile, essential oil supplementation during the nursery period also had a favorable effect on the performance of growing pigs. CONCLUSIONS: Therefore, the strategy of adding CEO to pig diets as a growth promoter and enhancing intestinal health is feasible.

3.
Molecules ; 27(19)2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36234921

RESUMEN

DNA-alkylating natural products play an important role in drug development due to their significant antitumor activities. They usually show high affinity with DNA through different mechanisms with the aid of their unique scaffold and highly active functional groups. Therefore, the biosynthesis of these natural products has been extensively studied, especially the construction of their pharmacophores. Meanwhile, their producing strains have evolved corresponding self-resistance strategies to protect themselves. To further promote the functional characterization of their biosynthetic pathways and lay the foundation for the discovery and rational design of DNA alkylating agents, we summarize herein the progress of research into DNA-alkylating antitumor natural products, including their biosynthesis, modes of action, and auto-resistance mechanisms.


Asunto(s)
Productos Biológicos , Alquilantes/farmacología , Productos Biológicos/farmacología , Vías Biosintéticas , ADN
4.
Biochem Biophys Res Commun ; 622: 122-128, 2022 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-35849953

RESUMEN

Two glycosylated naphthacemycins (naphthacemycins D1 and D2) were identified in Streptomyces sp. N12W1565. These two compounds not only showed antimicrobial potential against bacteria but also exhibited more aqueous solubility than naphthacemycins. Furthermore, the whole genome of Streptomyces sp. N12W1565 has been sequenced, the natY gene, located outside the biosynthetic gene cluster encoding a D-glucose glycosyltransferase, was identified to mediate glycosylation in the phenolic hydroxyl of the naphthacemycin core scaffold. Glycosyltransferase was elucidated in vitro by using a homologous enzyme, which showed potential as a biocatalyst.


Asunto(s)
Streptomyces , Antibacterianos/farmacología , Glicosilación , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Familia de Multigenes
5.
Angew Chem Int Ed Engl ; 58(50): 18046-18054, 2019 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-31553109

RESUMEN

One biosynthetic gene cluster (BGC) usually governs the biosynthesis of a series of compounds exhibiting either the same or similar molecular scaffolds. Reported here is a multiplex activation strategy to awaken a cryptic BGC associated with tetracycline polyketides, resulting in the discovery of compounds having different core structures. By constitutively expressing a positive regulator gene in tandem mode, a single BGC directed the biosynthesis of eight aromatic polyketides with two types of frameworks, two pentacyclic isomers and six glycosylated tetracyclines. The proposed biosynthetic pathway, based on systematic gene inactivation and identification of intermediates, employs two sets of tailoring enzymes with a branching point from the same intermediate. These findings not only provide new insights into the role of tailoring enzymes in the diversification of polyketides, but also highlight a reliable strategy for genome mining of natural products.


Asunto(s)
Familia de Multigenes , Policétidos/química , Policétidos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Perfilación de la Expresión Génica , Genes Bacterianos , Microorganismos Modificados Genéticamente , Estructura Molecular , Mutación , Regiones Promotoras Genéticas
7.
Rev Sci Instrum ; 87(12): 126102, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28040971

RESUMEN

Stability of the intermediate frequency (IF) in the far-infrared polarimeter-interferometer diagnostic system is critically important for the long pulse discharge experiments on the EAST tokamak. In this note, a real-time remote/local IF stability control system is described. The measured plasma parameters, including the Faraday rotation angle, electron density, lower hybrid wave, and plasma current, are obtained with the aid of this newly developed IF stability control system.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3163-8, 2016 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30222263

RESUMEN

Two series of chalcogenide glasses in Ge-Sb-S ternary system were synthesized with melt-quenching method. The phycochemical properties and spectral characteristic of glasses with different content of Ge and Sb were obtained with a series of measurements, and the systematic analysis on the change of optical properties was conducted in terms of microstructure of glasses combined with the Raman spectra. With constraint theory based on mean coordination number (Z), we described the variation trend of network structure directly. It was found that as long as the value of Z reaches 2.6, new vibration peaks would be formed in the Raman spectra indicating the presence of threshold behavior as well as the change of the network structure of the Ge-Sb-S glasses which could be expressed in a specific varition in the number of metal bonds and the nonmetal bonds. The appearance of new functional groups in the network have changed the total bond energy of glasses, and then affected the energy band structure of glasses representing the corresponding threshold behavior of the value of optical band gap (Eopg).

9.
Opt Lett ; 39(8): 2225-8, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24978957

RESUMEN

Downconversion materials, which can convert one high-energy photon to two low-energy photons, have provided a promising avenue for the enhancement of solar cell efficiency. In this work, the Pr3+-Yb3+ codoped 25GeS2-35Ga2S3-40CsCl chalcohalide glasses were synthesized in a vacuumed silica ampoule by the melting-quenching technique. Under 474 nm excitation, the visible and near-IR emission spectra reveal the energy transfer from Pr3+ to Yb3+ ions, resulting in the intense 1008 nm near-IR emission for the c-Si solar cells. By tuning the excitation laser power, it is determined that one visible photon has been cut into two near-IR photons during the energy transfer process. With the help of an integrated sphere, the real quantum yields of near-IR emissions were calculated. For the 0.2Pr2S3-0.2Yb2S3 (in mol.%) codoped chalcohalide glass, the quantum yield equals 10.8%. Although this efficiency is still low, this result will open a new route to realize the efficient spectral modification of the solar spectrum.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(4): 894-7, 2011 Apr.
Artículo en Chino | MEDLINE | ID: mdl-21714223

RESUMEN

A serial of chalcogenide glasses based on 78GeS2-12Ga2S3-10CsI (in molar%) system doped with the different radios of Ho3+/Tm3+ ions were synthesized by melt-quenching method. Their absorption spectra and mid-infrared fluorescence under 808 nm laser excitation were measured. According to Judd-Ofelt theory, the intensity parameters omega(i) (i = 2, 4, 6), spontaneous transition probabilities A(rad) and radiative lifetomes tau(r) for Ho3+ ion were calculated. Absorption cross-sections sigma(a), emission cross-sections sigma(e) and gain coefficient G(lambda) corresponding to the emission of Ho3+ ions at 2.0 microm were obtained. By changing the Tm3+ concentration, the energy transfer regime of Tm3+ and Ho3+ ions under 808 nm excitation was investigated. The results show that Ho3+/Tm(3+)-codoped Ge-Ga-S-CsI glasses would be a potential material for 2.0 microm emission.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(9): 2321-5, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21105387

RESUMEN

A series of chalcohalide glasses based on the composition 0.9 (Ge25 Ga5 S70)-0.1CsI doped with the different Tm3+ / Dy3+ ions ratio were synthesized by melt-quenching technique. The absorption spectra, and mid-infrared fluorescence of different glass samples under 800 nm laser excitation were measured. The results prove that, Tm3+ is an efficient sensitizer, which can enhance the Dy3+ : 2.9 microm fluorescence intensity significantly. A decrease in the intensity of 1.8 microm fluorescence and lifetimes of the Tm3+ : (3)F4 level occurred with increasing the concentration of Dy3+ ions from 0 to 1 Wt% where Tm3+ concentration was fixed to 0.5 Wt%. Also a wide spectral overlap between Tm+ : 1.8 microm emission and the absorption of Dy3+ : 6 H(15/2) --> (6)H(11/2) showed that the effective energy transfer between the two rare-earth ions was mainly attributed to the resonance energy from Tm3+: (3)F4 to Dy(3)+ : (6)H(11/2) level.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(6): 1464-8, 2010 Jun.
Artículo en Chino | MEDLINE | ID: mdl-20707130

RESUMEN

A series of chalcogenide glasses based on the composition Ge30 Ga5 Se65 (at. %) doped with the different Tm3+ ions were synthesized by melt-quenching technique. The refractive indexes, Raman spectra, absorption spectra, near-and mid-infrared fluorescence, and lifetimes of glass samples under 800 nm laser excitation were measured. The intensity parameters omega(i) (i = 2, 4, 6), transition probabilities, branching ratios and radiative lifetimes have been predicted for Tm3+ ions in samples by using the Judd-Ofelt theory. The near-infrared emission spectra at 1.23, 1.48 and 1.8 microm were observed and their quantum efficiencies were evaluated respectively in glass doped with 1 Wt% Tm(3+)-ions under 800 nm excitation. The mid-infrared fluorescence spectra were investigated with the different Tm3+ ion concentration under 800 nm excitation. The multiphonon relaxation rate of Tm3+ : 3 H5 --> 3F4 by the measured and calculated lifetimes, and the relative parameters of W(0) and a in Ge30 Ga5 Se65 glass were evaluated. Results show that the multiphonon relaxation rates were significantly lower than other glasses due to the lower maximum phonon energy, so the selenide glasses are promising as host materials for doping by rare earth ions and for preparation of mid-infrared optical elements.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(6): 1058-61, 2007 Jun.
Artículo en Chino | MEDLINE | ID: mdl-17763756

RESUMEN

One-dimensional Mn(2+)-doped CdS nanocrystals were synthesized by the hydrothermal route. The products were characterized by SEM, EDS, XRD, TEM, HRTEM and PL, respectively. The results revealed that dopant Mn2+ completely substitutes Cd2+ in CdS nanocrystals, and the product was of good crystallite. Further more, a complete suppression of the emission from surface states at room temperature when doping with ions Mn2+ has been observed.


Asunto(s)
Compuestos de Cadmio/química , Luminiscencia , Manganeso/química , Nanopartículas/química , Sulfuros/química , Calor , Mediciones Luminiscentes/métodos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanopartículas/ultraestructura , Espectrofotometría , Agua/química , Difracción de Rayos X
14.
Artículo en Inglés | MEDLINE | ID: mdl-16458052

RESUMEN

Er3+/Yb3+ co-doped TeO2-B2O3-Nb2O5-ZnO (TBN) glasses were prepared. The absorption spectra and upconversion luminescence spectra of TBN glasses were measured and analyzed. The upconversion emission bands centered at 530, 546 and 658 nm were observed under the excitation at 975 nm, corresponding to the transitions of 2H11/2-->4I15/2, 4S3/2-->4I15/2 and 4F9/2-->4I15/2 respectively. The ratio of red emission to green emission increases with an increasing of Yb3+ ions concentration. According to the quadratic dependence on excitation power, the possible upconversion mechanisms and processes were discussed.


Asunto(s)
Erbio/química , Fluorescencia , Vidrio/química , Telurio/química , Iterbio/química , Espectrofotometría
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(6): 960-3, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-16201383

RESUMEN

The LiNbO3 crystals doped with Cr3+ ion (Cr:LN) and co-doped with Cr3+ and Zn ions (Zn:Cr:LN) were grown by the Bridgman method. The absorption coefficient and concentration of Cr3+ in crystals were measured by UV/Visible spectra and inductively coupled plasma (ICP) spectrometry, respectively. The effective distribution coefficients (k) of Cr3+ in the crystals were calculated. The results indicated that the k for Cr:LN crystal decreased from 3.75 to 2.49 as the incorporating concentration of Cr3+ increased from 0.1 to 0.5 mol%; the introduction of ZnO in Cr:LN induced the reduction of k value effectively. However, the k value increased from 1.85 to 2.25 as the incorporating concentration of ZnO increased from 3 to 6 mol%. The variation of the k value was explained by the suppressing effect of ZnO on the incorporation of Cr3+ ions and the distribution of Cr3+ in LN.


Asunto(s)
Compuestos de Cromo/análisis , Niobio/química , Óxidos/química , Espectrofotometría Ultravioleta/métodos , Espectrofotometría/métodos , Cromo/análisis , Cromo/química , Compuestos de Cromo/química , Cristalización , Cinética , Modelos Químicos , Óxido de Zinc/química
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(6): 971-4, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-16201386

RESUMEN

Polyvinylpyrrolidone (PVP)-modified CdS nanorods were prepared by a hydrothermal reaction of CdCl2 2.5H2O and (NH4)2S with 10 wt% ethylenediamine aqueous solution as solvent and 1.0 wt% PVP as additives. The obtained products were characterized by means of XRD, TEM, IR, DTA-TG, UV-Vis and PL spectroscopies. The surface-modified CdS nanorods showed narrow size distribution and enhanced luminescence property compared with that of the unmodified ones. The UV-Vis spectra exhibited a structure peak. These results were attributed to the surface passivation of the CdS nanorods by the PVP molecules.


Asunto(s)
Compuestos de Cadmio/química , Nanotubos/química , Povidona/química , Análisis Espectral/métodos , Sulfuros/química , Cloruro de Cadmio/química , Compuestos de Cadmio/síntesis química , Microscopía Electrónica de Transmisión , Nanotubos/ultraestructura , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Sulfuros/síntesis química , Difracción de Rayos X
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(13-14): 2822-6, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16165019

RESUMEN

The Er3+/Yb3+-codoped 70TeO2-5Li2O-10B2O3-15GeO2 glass was prepared. The thermal stability, absorption spectra, emission spectra and up-conversion spectra were measured and investigated. The Judd-Ofelt analysis based on absorption spectra was performed in order to determine the Judd-Ofelt intensity parameters Omega(t) (t = 2, 4, 6), spontaneous emission probability, radiative lifetime and branching ratios of several Er3+ transitions. It was found that this studied glass has good thermal stability, broad fluorescence full width at half maximum (FWHM), large stimulated emission cross-section and strong up-conversion emissions at about 532, 546 and 659 nm, corresponding to the 2H(11/2)-->4I(15/2), 4S(3/2)-->4I(15/2) and 4F(9/2)-->4I(15/2) transitions of Er3+, respectively under the excitation at 970 nm. The results suggest that this Er3+/Yb3+-codoped germano-tellurite glass may be a potentially useful material for developing potential amplifiers and up-conversion optical devices.


Asunto(s)
Erbio/química , Germanio/química , Vidrio/química , Litio/química , Telurio/química , Iterbio/química , Cationes Monovalentes/química , Espectrometría de Fluorescencia , Temperatura
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(8): 1939-43, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15863070

RESUMEN

The new Er3+/Yb3+ co-doped 70TeO2-5Li2O-(25-x)B2O3-xGeO2 (x = 0, 5, 10, 15 fand 20 mol.%) glasses were prepared. The thermal stability, absorption spectra, emission spectra and lifetime of the 4I(13/2) level of Er3+ ions were measured and studied. The FT-IR spectra were carried out in order to investigate the structure of local arrangements in glasses. It is found that the thermal stability, absorption cross-section of Yb3+, emission intensity and lifetime of the 4I(13/2) level of Er3+ increase with increasing GeO2 content in the glass composition, while the fluorescence width at half maximum (FWHM) at 1.5 um of Er3+ is about 70 nm. The obtained data suggest that this system glass can be used as a candidate host material for potential broadband optical amplifiers.


Asunto(s)
Erbio/química , Litio/química , Telurio/química , Iterbio/química , Vidrio , Calor , Modelos Estadísticos , Espectrofotometría , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(6): 1259-62, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15741130

RESUMEN

The novel Er(3+) single-doped and Er(3+)/Yb(3+) co-doped tellurite glasses were prepared. The effect of Yb(2)O(3) concentration on absorption spectra, emission spectra and upconversion spectra of glasses were measured and investigated. The emission intensity, fluorescence full width at half maximum (FWHM) and upconversion luminescence of Er(3+) go up with the increasing concentration of Yb(3+) ions. The maximum FWHM of (4)I(13/2) --> (4)I(15/2) transition of Er(3+) is approximate 77 nm for 1.41 x 10(21)ions/cm(3) concentration of Yb(3+)-doped glass. The visible upconversion emissions at about 532, 546 and 659 nm, corresponding to the (2)H(11/2) --> (4)I(15/2), (4)S(3/2) --> (4)I(15/2) and (4)F(9/2) --> (4)I(15/2) transitions of Er(3+), respectively, were simultaneously observed under the excitation at 970 nm. Subsequently, the possible upconversion mechanisms and important role of Yb(3+) on the green and red emissions were discussed and compared. The results demonstrate that this kind of tellurite glass may be a potentially useful material for developing potential amplifiers and upconversion optical devices.


Asunto(s)
Erbio/química , Vidrio/química , Óxidos/química , Telurio/química , Tulio/química , Iterbio/química , Mediciones Luminiscentes , Fosfatidiletanolaminas , Espectrofotometría
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