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1.
J Musculoskelet Neuronal Interact ; 18(4): 525-529, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30511956

RESUMO

OBJECTIVE: This study aims to explore the effects of 25-hydroxyvitamin D on the bone microstructure of rats with type 2 diabetes mellitus (T2MD). METHODS: 40 male Wistar rats were randomly selected for T2MD modeling and injected with streptozotocin solution. The rats in the control group (n=19) were fed with common feed. 25-hydroxyvitamin D was injected into rats with successful modeling results (Treatment group, n=15). The remaining rats were considered as the model group (n=16). The enzyme-linked immunosorbent assay was adopted to determine bone gla protein (BGP) and tartrate-resistant acid phosphatase (TRACP), and an X-ray bone densitometer were applied to observe the vertebral sections. RESULTS: The activity levels of blood glucose, triglyceride, total cholesterol and TRACP in the model group were higher than those in the treatment group and the control group (p⟨0.01), while serum calcium, phosphorus, BGP, ALP, and glycosylated hemoglobin, various indicators of rats in the model group were lower than those in the treatment group and the control group (p⟨0.05). CONCLUSIONS: It is feasible to treat rats with T2MD with 25-hydroxyvitamin D, which can maintain the integrity of bone microstructure and increase the bone health.


Assuntos
Densidade Óssea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/tratamento farmacológico , Vitamina D/análogos & derivados , Animais , Densidade Óssea/fisiologia , Diabetes Mellitus Tipo 2/sangue , Masculino , Ratos , Ratos Wistar , Resultado do Tratamento , Vitamina D/farmacologia , Vitamina D/uso terapêutico
2.
Opt Lett ; 40(11): 2618-21, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26030572

RESUMO

We demonstrate a photonic radio-frequency transmission system via optical fiber. Optical radio-frequency signal is generated utilizing a Mach-Zehnder modulator based on double-side-band with carrier suppression modulation scheme. The phase error induced by optical fiber transmission is transferred to an intermediate frequency signal by the dual-heterodyne phase error transfer scheme, and then canceled by a phase locked loop. With precise phase compensation, a radio frequency with high-phase stability can be obtained at the remote end. We performed 20.07-GHz radio-frequency transfer over 100-km optical fiber, and achieved residual phase noise of -65 dBc/Hz at 1-Hz offset frequency, and the RMS timing jitter in the frequency range from 0.01 Hz to 1 MHz reaches 110 fs. The long-term frequency stability also achieves 8×10(-17) at 10,000 s averaging time.

3.
Opt Lett ; 39(10): 2849-52, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24978219

RESUMO

We demonstrate a phase-stabilized remote distribution of 100.04 GHz millimeter wave signal over 60 km optical fiber. The phase error of the remote millimeter wave signal induced by fiber transmission delay variations is detected by dual-heterodyne phase error transfer and corrected with a feedback system based on a fast response acousto-optic frequency shifter. The phase noise within the bandwidth of 300 Hz is effectively suppressed; thus, the fast transmission delay variations can be compensated. The residual phase noise of the remote 100.04 GHz signal reaches -56 dBc/Hz at 1 Hz frequency offset from the carrier, and long-term stability of 1.6×10(-16) at 1000 s averaging time is achieved. The fast phase-noise-correcting capability is evaluated by vibrating part of the transmission fiber link.

4.
Opt Lett ; 39(6): 1493-6, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24690821

RESUMO

Optical generation of highly stable millimeter and terahertz waves is proposed and experimentally demonstrated. The optical-fiber-path-induced phase fluctuation is identically transferred to a 40 MHz intermediate frequency by using dual-heterodyne phase error transfer, then canceled by a phase-locked loop. Based on the scheme, highly stable signals within the frequency range from 25 GHz to 1 THz are generated, and the phase jitter is decreased from 2.05 rad to 4.7 mrad in the frequency range from 0.01 Hz to 1 MHz. For 1 THz, the residual phase noise reaches -60 dBc/Hz at 1 Hz frequency offset from the carrier, and the relative timing jitter is reduced to 0.7 fs.

5.
Biomed Rep ; 2(2): 245-249, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24649104

RESUMO

This study was conducted to evaluate the application value of optimized treatment with radiofrequency (RF) thermotherapy and immunotherapy combined with CyberKnife for advanced high-risk tumors. The database of 1,013 patients with 2,136 tumor lesions and 1,237 target areas who underwent treatment with CyberKnife between November, 2010 and November, 2012, was retrospectively reviewed. We randomly assigned 505 eligible patients (observation group) to RF thermotherapy and adoptive immunotherapy with cytokine-induced killer cells and the remaining 508 patients (control group) to no adjuvant treatment. The patients in the two groups were recorded on efficacy assessment according to imageological examination, World Health Organization criteria, Karnofsky performance status, or radioimmunoassay (RIA) detection. The effective rate of the observation group was 75.05%, whereas that of the control group was 58.06% (P<0.05). The results revealed that CyberKnife combined with hyperthermia and biological therapy are highly effective in improving the local tumor control rate. Further analysis of the Karnofsky score and RIA detection confirmed that this type of combination therapy significantly improved the quality of life. The optimized treatment of RF thermotherapy and immunotherapy combined with CyberKnife may act synergistically in eliminating tumor cells, confirming the efficacy of this type of treatment for patients with advanced malignant tumors.

6.
Biomed Rep ; 2(2): 250-254, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24649105

RESUMO

Accumulating evidence indicates that aged black garlic extract (ABGE) may prove beneficial in preventing or inhibiting oncogenesis; however, the underlying mechanisms have not been fully elucidated. The present study aimed to investigate the effects of ABGE on the proliferation and apoptosis of HT29 colon cancer cells. Our results demonstrated that ABGE inhibited HT29 cell growth via the induction of apoptosis and cell cycle arrest. We further investigated the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signal transduction pathway and the molecular mechanisms underlying the ABGE-induced inhibition of HT29 cell proliferation. We observed that ABGE may regulate the function of the PI3K/Akt pathway through upregulating PTEN and downregulating Akt and p-Akt expression, as well as suppressing its downstream target, 70-kDa ribosomal protein S6 kinase 1, at the mRNA and protein levels. In conclusion, these findings suggest that the PI3K/Akt signal transduction pathway is crucial for the development of colon cancer. ABGE inhibited the growth and induced apoptosis in HT29 cells through the inhibition of the PI3K/Akt pathway, suggesting that ABGE may be effective in the prevention and treatment of colon cancer in humans.

7.
Opt Lett ; 39(4): 888-91, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24562233

RESUMO

We have developed a radio-frequency local oscillator remote distribution system, which transfers a phase-stabilized 10.03 GHz signal over 100 km optical fiber. The phase noise of the remote signal caused by temperature and mechanical stress variations on the fiber is compensated by a high-precision phase-correction system, which is achieved using a single sideband modulator to transfer the phase correction from intermediate frequency to radio frequency, thus enabling accurate phase control of the 10 GHz signal. The residual phase noise of the remote 10.03 GHz signal is measured to be -70 dBc/Hz at 1 Hz offset, and long-term stability of less than 1×10⁻¹6 at 10,000 s averaging time is achieved. Phase error is less than ±0.03π.

8.
Oncol Lett ; 6(2): 534-536, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24137362

RESUMO

Brain metastasis is a significant cause of morbidity and mortality and a critical complication of non-central nervous system primary carcinoma. The present study describes the clinical case of a 46-year-old male with lung cancer and life-threatening brain metastases. The patient was diagnosed with lung cancer with a clinical stage of T2N0M1 (stage IV). Six months after the initial diagnosis and administration of conformal radiotherapy combined with three cycles of chemotherapy, an enhanced computed tomography (CT) scan of the brain revealed abnormalities with double-dosing of intravenous contrast. The CT scan identified >24 lesions scattered in the whole brain. The patient was treated with three-fraction Cyberknife radiotherapy at 22 Gy, delivered to the brain metastases at the Center for Tumor Treatment of People's Liberation Army 107th Hospital. Following CyberKnife therapy, a CT scan of the brain revealed that most of the tumors had disappeared with almost no residual traces. The stereotactic radiosurgery (SRS) conducted using CyberKnife, an image-guided frameless robotic technology for whole-body radiosurgery, had produced a marked response. The present case report demonstrates that CyberKnife therapy plays a significant role in the management of multiple meta-static brain tumors.

9.
Mol Clin Oncol ; 1(3): 527-530, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24649205

RESUMO

Non-small cell lung cancer (NSCLC) is responsible for at least 80% of all lung tumors and has a poor prognosis, since 75% of NSCLCs are first diagnosed at an advanced stage. This study was conducted to evaluate the therapeutic efficacy of CyberKnife in combination with chemotherapy and hyperthermia for selected patients with advanced non-small cell lung cancer (NSCLC). Clinical charts, imaging and pathology reports of patients with advanced NSCLC who underwent CyberKnife therapy in our Tumor Therapy Center were retrospectively reviewed. Clinical efficacy was evaluated for local control, Karnofsky performance status scale (KPS) and toxicity analysis. A total of 119 patients with 136 target areas were evaluated. A prescribed dose of 24-51 Gy to the gross tumor volume was delivered in 3-6 fractions. The median prescription dose was 35 Gy (mean, 34.73±4.80 Gy), with an average of five fractions. Patients, who voluntarily participated in the study, were assigned to one of three groups, which were as follows: CyberKnife therapy alone, CyberKnife combined with chemotherapy and CyberKnife combined with chemotherapy and hyperthermia. The median follow-up period was 6 months and curative efficiencies were 62.16, 71.79 and 90.70%, respectively, as determined by radiographic and clinical re-examinations. Patients treated by CyberKnife combined with chemotherapy and hyperthermia achieved optimal improvement in the aspect of KPS, which was statistically different compared to the other two groups (P<0.05). In conclusion, our results indicated that CyberKnife combined with chemotherapy and hyperthermia achieved favorable short-term outcomes and may be a more viable option for patients with advanced NSCLC. However, further investigations are required to evaluate long-term outcomes.

10.
Tissue Eng ; 13(2): 405-14, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17504064

RESUMO

Cartilage tissue engineering strategies generally result in homogeneous tissue structures with little resemblance to the native zonal organization of articular cartilage. The objective of this study was to use bilayered photopolymerized hydrogels to organize zone-specific chondrocytes in a stratified framework and study the effects of this three-dimensional coculture system on the properties of the engineered tissue. Superficial and deep zone chondrocytes from bovine articular cartilage were photoencapsulated in separate hydrogels as well as in adjacent layers of a bilayered hydrogel. Histology, mechanical testing, and biochemical analysis was performed after culturing in vitro. To evaluate the influence of coculture on tissue properties, the layers were separated and compared to constructs containing only superficial or deep cells. In the bilayered constructs, deep cells produced more collagen and proteoglycan than superficial cells, resulting in cartilage tissue with stratified, heterogeneous properties. Deep cells cocultured with superficial cells in the bilayered system demonstrated reduced proliferation and increased matrix synthesis compared to deep cells cultured alone. The bilayered constructs demonstrated greater shear and compressive strength than homogenous cell constructs. This study demonstrated that interactions between zone-specific chondrocytes affect the biological and mechanical properties of engineered cartilage. Strategies aimed to structurally organize zone-specific cells and encourage heterotypic cell interactions may contribute to improved functional properties of engineered cartilage.


Assuntos
Cartilagem/citologia , Cartilagem/crescimento & desenvolvimento , Comunicação Celular/fisiologia , Condrócitos/citologia , Condrócitos/fisiologia , Técnicas de Cocultura/métodos , Engenharia Tecidual/métodos , Animais , Bovinos , Técnicas de Cultura de Células/métodos , Proliferação de Células , Sobrevivência Celular , Células Cultivadas
11.
Biorheology ; 39(1-2): 11-25, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12082263

RESUMO

A non-invasive methodology (based on video microscopy, optimized digital image correlation and thin plate spline smoothing technique) has been developed to determine the intrinsic tissue stiffness (H(a)) and the intrinsic fixed charge density (c(0)(F)) distribution for hydrated soft tissues such as articular cartilage. Using this technique, the depth-dependent inhomogeneous parameters H(a)(z) and c(0)(F)(z) were determined for young bovine cartilage and incorporated into a triphasic mixture model. This model was then used to predict the mechanical and electrochemical events (stress, strain, fluid/osmotic pressure, and electrical potentials) inside the tissue specimen under a confined compression stress relaxation test. The integration of experimental measurements with theoretical analyses can help to understand the unique material behaviors of articular cartilage. Coupled with biological assays of cell-scale biosynthesis, there is also a great potential in the future to study chondrocyte mechanotransduction in situ with a new level of specificity.


Assuntos
Cartilagem Articular/fisiologia , Condrócitos/fisiologia , Animais , Bovinos , Força Compressiva , Técnicas In Vitro , Modelos Biológicos , Osmose , Estresse Mecânico
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