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1.
Clin Exp Dermatol ; 44(4): e96-e102, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30710383

RESUMO

BACKGROUND: A new therapeutic device passes radiofrequency energy through microneedles to targeted tissue. Three-dimensional photography may be useful for evaluating the clinical efficacy of microneedle fractional radiofrequency (MFR) used on the appearance of rhytids and to improve facial laxity. AIM: To evaluate the efficacy and safety of MFR in the treatment of facial photoageing. METHODS: In total, participants with facial photoageing were enrolled in the study. All volunteers were randomized to receive split-face treatments with MFR 2 months apart. The participants self-evaluated at baseline, Days 1-7, and Months 1 and 3 after the final treatment. Objective evaluation was provided by a three-dimensional in vivo imaging system. In addition, skin melanin index, erythema index, immediate reactions, healing times and other adverse effects were evaluated. RESULTS: Compared with the untreated side, the treated side of most participants improved, based on clinical assessments at the 1- and 3-month follow-up visits after treatment. Both objective and participative assessments were satisfactory. The participants demonstrated a decrease of roughness parameter (Sa) value at each follow-up visit. Compared with pretreatment value, Sa decreased significantly at Months 1 and 3 on the treated side (P < 0.05). Minimal and reversible adverse effects and rapid healing were recorded. CONCLUSIONS: MFR appears to be an excellent treatment for photodamaged facial skin in Chinese patients.


Assuntos
Face/fisiopatologia , Tratamento por Radiofrequência Pulsada/instrumentação , Envelhecimento da Pele/efeitos da radiação , Pele/efeitos da radiação , Adulto , China/epidemiologia , Técnicas Cosméticas/instrumentação , Eritema/etiologia , Eritema/patologia , Feminino , Humanos , Imageamento Tridimensional/métodos , Melaninas/efeitos da radiação , Pessoa de Meia-Idade , Agulhas , Satisfação do Paciente , Tratamento por Radiofrequência Pulsada/efeitos adversos , Pele/metabolismo , Pele/patologia , Envelhecimento da Pele/patologia , Resultado do Tratamento
2.
Phys Rev Lett ; 112(6): 066801, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24580700

RESUMO

We present transport measurements of cleaved edge overgrowth GaAs quantum wires. The conductance of the first mode reaches 2e(2)/h at high temperatures T≳10 K, as expected. As T is lowered, the conductance is gradually reduced to 1e(2)/h, becoming T independent at T≲0.1 K, while the device cools far below 0.1 K. This behavior is seen in several wires, is independent of density, and not altered by moderate magnetic fields B. The conductance reduction by a factor of 2 suggests lifting of the electron spin degeneracy in the absence of B. Our results are consistent with theoretical predictions for helical nuclear magnetism in the Luttinger liquid regime.

3.
Intern Med J ; 44(7): 653-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24750253

RESUMO

BACKGROUND: The presence of silent cerebral infarction (SCI) increases the risk of transient ischaemia attack, symptomatic stroke, cardiovascular disease and dementia. Mean platelet volume (MPV) is a surrogate marker of activated platelets and is considered a link between inflammation and thrombosis. In addition, MPV is a risk predictor for cardiovascular disease, stroke and overall vascular mortality. AIMS: The purpose of the study was to assess the MPV levels in SCI patients. METHODS: A cross-sectional study was conducted to evaluate the association between MPV and SCI in 2215 subjects (1385 men and 830 women). RESULTS: The participants with SCI had higher MPV levels than those without SCI (10.4 ± 1.3 fL vs. 9.2 ± 1.2 fL; P < 0.001). Moreover, the subjects with a high MPV had a higher prevalence of SCI. Multivariate logistic regression analyses revealed that the odds ratios and 95% confidence intervals for SCI according to MPV quartiles were 1.000, 2.131 (1.319-3.444), 3.015 (1.896-4.794), 7.822 (4.874-12.554) respectively (P < 0.001). CONCLUSION: MPV is a novel index for SCI regardless of classical cardiovascular risk factors.


Assuntos
Infarto Cerebral/sangue , Infarto Cerebral/diagnóstico , Adulto , Biomarcadores/sangue , Infarto Cerebral/epidemiologia , Estudos Transversais , Feminino , Humanos , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/epidemiologia , Masculino , Volume Plaquetário Médio/tendências , Pessoa de Meia-Idade
4.
Genet Mol Res ; 11(4): 3852-60, 2012 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-23212324

RESUMO

Association between the XRCC1 Arg399Gln polymorphism and susceptibility to gastric cancer has been investigated; overall, the results have been inconclusive. We made a meta-analysis of 13 case-control studies, including 3278 cases and 6243 controls. Crude odds ratios (OR) with 95% confidence intervals (95%CI) were used to assess this possible association. We found no evidence of a significant association between the XRCC1 Arg399Gln polymorphism and gastric cancer risk (in the additive inheritance model, OR = 0.986, 95%CI = 0.831-1.156, in the dominant inheritance model, OR = 1.044, 95%CI = 0.890-1.224 and in the recessive inheritance model, OR = 0.975, 95%CI = 0.894-1.063). We conclude that the XRCC1 Arg399Gln polymorphism is not a risk factor for developing gastric cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Neoplasias Gástricas/genética , Substituição de Aminoácidos/genética , Intervalos de Confiança , Humanos , Razão de Chances , Viés de Publicação , Fatores de Risco , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
5.
J Phys Condens Matter ; 34(13)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-34986474

RESUMO

We present an anomalous Josephson effect in a TI-based Josephson junction with a ferromagnetic insulator (FI) trilayer which has noncoplanar magnetizations. It is shown that there exist equal fractional spin-singlet and -triplet correlations due to the magnetism-tuning chiral Dirac energy band structure. The consequent anomalous Josephson supercurrent is exhibited, in which a 0-πor similar 0-πstate transition through phase shift is induced only by exchange field strength of the first FI region, while theϕ0supercurrent and the maximum one gradually drop with the increase of exchange field strengths of the second and third FI regions without relative state transitions. With the increase of the FI region length, theϕ0supercurrent and the maximum one are also both decreased, are found, which is different from the situation for increasing the exchange filed strength. In addition, the corresponding free energies are presented and discussed.

6.
Zhonghua Shao Shang Za Zhi ; 36(7): 575-578, 2020 Jul 20.
Artigo em Zh | MEDLINE | ID: mdl-32077677

RESUMO

The prevention and control of coronavirus disease 2019 (COVID-19) has already entered a key period. The patients treated in the burn and wound care ward are susceptible to viral infection because of disease, age and other factors, so it is very important to manage the burn and wound care ward during the prevention and control of COVID-19 pandemic. In this paper, combining with the key clinical problems of prevention and control in hospital during the epidemic period of COVID-19 infection, medical evidence, and clinical and management experience, the authors formulate prevention and control management strategy of the author's unit in order to provide reference for prevention and control of burn and wound care ward.


Assuntos
Unidades de Queimados/organização & administração , Queimaduras/terapia , Infecções por Coronavirus/prevenção & controle , Coronavirus , Pandemias , Pneumonia Viral/prevenção & controle , Betacoronavirus , COVID-19 , Infecções por Coronavirus/epidemiologia , Humanos , Pneumonia Viral/epidemiologia , SARS-CoV-2
7.
Nat Commun ; 10(1): 1756, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30988403

RESUMO

Sub-picosecond magnetisation manipulation via femtosecond optical pumping has attracted wide attention ever since its original discovery in 1996. However, the spatial evolution of the magnetisation is not yet well understood, in part due to the difficulty in experimentally probing such rapid dynamics. Here, we find evidence of a universal rapid magnetic order recovery in ferrimagnets with perpendicular magnetic anisotropy via nonlinear magnon processes. We identify magnon localisation and coalescence processes, whereby localised magnetic textures nucleate and subsequently interact and grow in accordance with a power law formalism. A hydrodynamic representation of the numerical simulations indicates that the appearance of noncollinear magnetisation via optical pumping establishes exchange-mediated spin currents with an equivalent 100% spin polarised charge current density of 107 A cm-2. Such large spin currents precipitate rapid recovery of magnetic order after optical pumping. The magnon processes discussed here provide new insights for the stabilization of desired meta-stable states.

8.
Rev Sci Instrum ; 88(4): 043902, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28456265

RESUMO

We present a parallel network of 16 demagnetization refrigerators mounted on a cryofree dilution refrigerator aimed to cool nanoelectronic devices to sub-millikelvin temperatures. To measure the refrigerator temperature, the thermal motion of electrons in a Ag wire-thermalized by a spot-weld to one of the Cu nuclear refrigerators-is inductively picked-up by a superconducting gradiometer and amplified by a SQUID mounted at 4 K. The noise thermometer as well as other thermometers are used to characterize the performance of the system, finding magnetic field independent heat-leaks of a few nW/mol, cold times of several days below 1 mK, and a lowest temperature of 150 µK of one of the nuclear stages in a final field of 80 mT, close to the intrinsic SQUID noise of about 100 µK. A simple thermal model of the system capturing the nuclear refrigerator, heat leaks, and thermal and Korringa links describes the main features very well, including rather high refrigerator efficiencies typically above 80%.

9.
Neurosci Lett ; 287(2): 117-20, 2000 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-10854726

RESUMO

Striatal glutamate release during novelty exposure-induced hyperactivity was studied by microdialysis in freely-moving olfactory bulbectomized (OBX) rats. After collecting three 10 min basal striatal dialysate samples, the animals were transferred to an open-field apparatus (novelty) and locomotor activity recorded for 60 min. OBX rats showed significantly more locomotor activity (1210+/-270 cm) than sham-operated rats (420+/-70 cm), but only in the first 10 min after exposure to the novel environment. During the same period, striatal glutamate levels increased to 163+/-21% of the basal value in OBX rats, while no changes were seen in the striatum of sham-operated controls. These findings suggest that olfactory bulbectomy results in an increased response of the striatal glutamatergic system to novelty stress, and may consequently cause hyperactivity.


Assuntos
Corpo Estriado/metabolismo , Comportamento Exploratório/fisiologia , Ácido Glutâmico/metabolismo , Bulbo Olfatório/cirurgia , Estresse Fisiológico/fisiopatologia , Animais , Comportamento Animal/fisiologia , Denervação , Locomoção/fisiologia , Masculino , Microdiálise , Agitação Psicomotora/fisiopatologia , Ratos , Ratos Wistar
10.
Thromb Res ; 57(5): 747-53, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2140208

RESUMO

Fluorescent humic substances (FHS) in well water of Blackfoot disease endemic areas were purified and fractionated by Sephadex G-25 column chromatography. Four fractions of the purified FHS were isolated. The purified FHS and their fractions were then added to normal human pool plasma in vitro separately to detect the abilities of the effects on prothrombin time (PT) and activated thromboplastin time (APTT). Results showed that all of the four fractions of the purified FHS prolonged both PT and APTT in the higher concentration ranges (10 mg/ml - 20 mg/ml), but shortened both PT and APTT in the lower concentration ranges (0.5 mg/ml - 5 mg/ml). Among the four fractions of the FHS, the fraction 1, the humic substance with the highest molecular weight among all the four FHS, showed the most obvious effects. Owing to the effects of the FHS on PT and APTT values, we supposed that there is a close relationship between the FHS and the cause of Blackfoot disease.


Assuntos
Arteriopatias Oclusivas/induzido quimicamente , Coagulação Sanguínea/efeitos dos fármacos , Substâncias Húmicas/farmacologia , Poluentes da Água/farmacologia , Arsênio/efeitos adversos , Arsênio/metabolismo , Humanos , Substâncias Húmicas/efeitos adversos , Substâncias Húmicas/metabolismo , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Taiwan , Poluentes da Água/efeitos adversos , Poluentes da Água/isolamento & purificação , Abastecimento de Água/análise
11.
Biophys Chem ; 56(3): 281-96, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7578905

RESUMO

Using polyacrylamide gel electrophoresis (PAGE) and low-temperature, laser-induced fluorescence line narrowing (FLN) and non-line narrowing (NLN) spectroscopic methods, the conformational characteristics of stereochemically defined and site-specific adducts derived from the binding of 7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10- tetrahydrobenzo[a]pyrene (anti-BPDE, a metabolite of the environmental carcinogen benzo[a]pyrene), to DNA were studied. The focus of these studies was on the four stereochemically distinct anti-BPDE modified duplexes 5'-d(CCATCGCTACC).(GGTAGCGATGG), where G denotes the lesion site derived from trans or cis addition of the exocyclic amino group of guanine to the C10 position of either (+) or (-)-anti-BPDE. PAGE experiments under non-denaturing conditions showed that the (+)-trans adduct causes a significantly greater retardation in the electrophoretic mobility than the other three adducts, probably the result of important adduct-induced distortions of the duplex structure. Low-temperature fluorescence studies in frozen aqueous buffer matrices showed that the (+)-trans adduct adopts primarily an external conformation with only minor interactions with the helix, but a smaller fraction (approximately 25%) appears to exists in a partially base-stacked conformation. The (-)-trans adduct exists almost exclusively (approximately 97%) in an external conformation. Both cis adducts were found to be intercalated; strong electron-phonon coupling observed in their FLN spectra provided additional evidence for significant pi-pi stacking interactions between the pyrenyl residues and the bases. FLN spectroscopy is shown to be suitable for distinguishing between trans and cis adducts, but lesions with either (+)- or (-)-trans, or (+)- or (-)-cis stereochemical characteristics showed very similar vibrational patterns.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Benzo(a)pireno/química , Benzopirenos/química , Adutos de DNA/química , Sequência de Bases , Fenômenos Biofísicos , Biofísica , Fenômenos Químicos , Físico-Química , Conformação Molecular , Dados de Sequência Molecular , Estrutura Molecular , Oligonucleotídeos/química , Espectrometria de Fluorescência , Estereoisomerismo , Temperatura
12.
Angiology ; 39(8): 714-9, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3421505

RESUMO

The new method of lateral carotid artery original-location autograft was used in the present study. An animal model was prepared with which to investigate the neurogenic role in the pathogenesis of atherosclerosis. Two experiments were performed in 16 operated rabbits to whom was fed a cholesterol-rich diet for four months. In the first experiment, the expected results were obtained in 9 rabbits. Significant atherosclerotic plaques were observed in 4 of 9 (44.4%) samples of intact carotid artery; lipid deposition was found in another 3 (33.3%) samples in which atherosclerotic plaques were not observed by the naked eye but were exhibited by light microscopy; negative results were shown only in 2 (22.2%) samples both by the naked eye and by light microscopy. However, atherosclerotic plaques were found only in autograft anastomoses but not within the segment of carotid artery autograft. Then, a second experiment as performed with 7 operated rabbits, and similar results were obtained. These results clearly indicate that the nervous system plays a very important role in the pathogenesis of atherosclerosis.


Assuntos
Arteriosclerose/etiologia , Doenças das Artérias Carótidas/etiologia , Fenômenos Fisiológicos do Sistema Nervoso , Anastomose Cirúrgica , Animais , Arteriosclerose/sangue , Arteriosclerose/patologia , Artérias Carótidas/transplante , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/patologia , Colesterol/sangue , Metabolismo dos Lipídeos , Masculino , Coelhos , Transplante Autólogo
13.
Artigo em Inglês | MEDLINE | ID: mdl-11477782

RESUMO

In this study, a recurrent fuzzy neural network (RFNN) controller is proposed to control a piezoelectric ceramic linear ultrasonic motor (LUSM) drive system to track periodic reference trajectories with robust control performance. First, the structure and operating principle of the LUSM are described in detail. Second, because the dynamic characteristics of the LUSM are nonlinear and the precise dynamic model is difficult to obtain, a RFNN is proposed to control the position of the moving table of the LUSM to achieve high precision position control with robustness. The back propagation algorithm is used to train the RFNN on-line. Moreover, to guarantee the convergence of tracking error for periodic commands tracking, analytical methods based on a discrete-type Lyapunov function are proposed to determine the varied learning rates of the RFNN. Then, the RFNN is implemented in a PC-based computer control system, and the LUSM is driven by a unipolar switching full bridge voltage source inverter using LC resonant technique. Finally, the effectiveness of the RFNN-controlled LUSM drive system is demonstrated by some experimental results. Accurate tracking response and superior dynamic performance can be obtained because of the powerful on-line learning capability of the RFNN controller. Furthermore, the RFNN control system is robust with regard to parameter variations and external disturbances.

14.
Scanning ; 23(4): 249-54, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11534811

RESUMO

With its output wavelength covering the infrared penetrating window of most biological tissues at 1,200-1,250 nm, the femtosecond Cr:forsterite laser shows high potential to serve as an excellent excitation source for the multiphoton fluorescence microscope. Its high output power, short optical pulse width, high stability, and low dispersion in fibers make it a perfect replacement for the currently widely used Ti:sapphire laser. In this paper, we study the capability of using a femtosecond Cr:forsterite laser in multiphoton scanning microscopy. We have performed the multiphoton excited photoluminescence spectrum measurement on several commonly used bioprobes using the 1,230 nm femtosecond pulses from a Cr:forsterite laser. Efficient fluorescence can be easily observed in these bioprobes through two-photon or three-photon excitation processes. These results will assist in the selection of dichroic beam splitter and band pass filters in a multiphoton microscopic system. We have also performed the autofluorescence spectrum measurement from chlorophylls in live leaves of the plant Arabidopsis thaliana excited by 1,230 nm femtosecond pulses from the Cr:forsterite laser. Bright luminescence from chlorophyll, centered at 673 and 728 nm, respectively, can be easily observed. Taking advantage of the bright two-photon photoluminescence from chlorophyll, we demonstrated the two-photon scanning paradermal and cross-sectional images of palisade mesophyll cells in live leaves of Arabidopsis thaliana.


Assuntos
Cromo , Microscopia Confocal/instrumentação , Folhas de Planta/ultraestrutura , Arabidopsis , Técnicas Biossensoriais , Compostos de Boro , Corantes Fluorescentes , Lasers , Microscopia Confocal/métodos , Compostos Orgânicos , Fótons
20.
Neuroscience ; 153(3): 823-31, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18400403

RESUMO

We previously showed that intrathecal co-administration of amitriptyline with morphine upregulates the expression of the glial glutamate transporters glutamate-aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1) and restores neuronal glutamate transporter excitatory amino acid carrier 1 (EAAC1) expression in chronically morphine-infused rats. The present study examined the role of nuclear transcription factor-kappaB (NF-kappaB) in the regulation of the expression of GLAST, GLT-1, and EAAC1 following long-term amitriptyline/morphine co-infusion. Male Wistar rats were implanted with two intrathecal catheters with or without a microdialysis probe; one of the catheters was used for continuous infusion of saline (control), morphine (15 microg/h), or morphine plus amitriptyline (both 15 microg/h) for 5 days, while the other was used for a single daily intrathecal injection of the NF-kappaB inhibitor Ro106-9920 (10 microl of 10 microM) for 5 days. We found that amitriptyline co-infusion restored the antinociceptive effect of morphine (4.5-fold right-shift in the morphine dose-response curve compared with a 65-fold right-shift in its absence) and this effect was inhibited by Ro106-9920 administration (48-fold right-shift). Moreover, amitriptyline/morphine co-infusion increased IkappaBalpha phosphorylation and the translocation of NF-kappaB p65 from the cytosol to the nucleus. Daily intrathecal injection of Ro106-9920 prevented the amitriptyline/morphine-induced NF-kappaB p65 translocation and reversed the amitriptyline/morphine-induced GLAST and GLT-1 upregulation and inhibited the restoration of EAAC1 expression. The Ro106-9920 injections abolished the inhibitory effect of amitriptyline on the morphine-evoked release of excitatory amino acids into the spinal cerebrospinal fluid (CSF) dialysates. In conclusion, amitriptyline/morphine co-infusion restores the antinociceptive effect of morphine and upregulates GLAST and GLT-1 expression and restores EAAC1 expression to baseline levels, thus reducing excitatory amino acid levels in the spinal CSF dialysates. The mechanism involves activation of the NF-kappaB pathway, but may also involve other pathways.


Assuntos
Inibidores da Captação Adrenérgica/administração & dosagem , Sistema X-AG de Transporte de Aminoácidos/efeitos dos fármacos , Amitriptilina/administração & dosagem , NF-kappa B/efeitos dos fármacos , Entorpecentes/farmacologia , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Western Blotting , Relação Dose-Resposta a Droga , Interações Medicamentosas , Tolerância a Medicamentos/fisiologia , Aminoácidos Excitatórios/metabolismo , Imunofluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Processamento de Imagem Assistida por Computador , Injeções Espinhais , Masculino , Microdiálise , Morfina/farmacologia , NF-kappa B/metabolismo , Limiar da Dor/efeitos dos fármacos , Ratos , Ratos Wistar , Sulfóxidos/farmacologia , Tetrazóis/farmacologia , Regulação para Cima
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