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1.
Cell Death Dis ; 15(4): 271, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632264

RESUMO

Diabetes, a group of metabolic disorders, constitutes an important global health problem. Diabetes and its complications place a heavy financial strain on both patients and the global healthcare establishment. The lack of effective treatments contributes to this pessimistic situation and negative outlook. Exosomes released from mesenchymal stromal cells (MSCs) have emerged as the most likely new breakthrough and advancement in treating of diabetes and diabetes-associated complication due to its capacity of intercellular communication, modulating the local microenvironment, and regulating cellular processes. In the present review, we briefly outlined the properties of MSCs-derived exosomes, provided a thorough summary of their biological functions and potential uses in diabetes and its related complications.


Assuntos
Complicações do Diabetes , Diabetes Mellitus , Exossomos , Células-Tronco Mesenquimais , Humanos , Exossomos/metabolismo , Complicações do Diabetes/metabolismo , Comunicação Celular , Células-Tronco Mesenquimais/metabolismo , Resultado do Tratamento , Diabetes Mellitus/metabolismo
2.
Quant Imaging Med Surg ; 14(1): 408-420, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223085

RESUMO

Background: The status of the axillary lymph node (ALN) in patients with breast cancer can critically inform clinical decision-making and prognosis. Preoperative evaluation of limited nodal burden (0-2 metastatic ALNs) and high nodal burden (≥3 metastatic ALNs) is vital for individual treatment in patients with breast cancer. Thus, this study aimed to evaluate the value of Angio-PLUS (AP; Aixplorer, SuperSonic Imagine) and the qualitative and quantitative shear-wave elastography (SWE) of breast lesions to predict limited or high axillary nodal burden and to develop a model for predicting limited or high axillary nodal burden. Methods: From March 2020 to November 2022, a total of 232 consecutive patients with breast cancer comprising 232 breast lesions were enrolled retrospectively from Yueyang Central Hospital. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), accuracy, and area under the receiver operating characteristic curve (AUC) of AP, qualitative SWE, quantitative SWE, and the predictive model for evaluating limited or high axillary nodal burden were compared. Results: There was no significant difference in AP patterns between the limited nodal burden group and high nodal burden group. The best cutoff values of Emin (the minimal value of the first Q-box), Emean (the mean value of the first Q-box), Emax (the maximum value of the first Q-box), Eratio (ratio of the first Q-Box and the second Q-Box) and standard deviation for predicting limited or high nodal burden were 80.85 KPa, 133.45 KPa, 153.40 KPa, 9.95, and 19.25 KPa, respectively. The Emax had the highest AUC, and its sensitivity, specificity, PPV, NPV, accuracy, and AUC were 71.64%, 56.36%, 40.00%, 83.04%, 60.78%, and 0.640 [95% confidence interval (CI): 0.575-0.702], respectively. The sensitivity, specificity, PPV, NPV, accuracy, and AUC of seven color patterns for qualitative SWE were 71.64%, 74.55%, 53.33%, 86.62%, 73.71%, and 0.731 (95% CI: 0.669-0.787), respectively, which was significantly higher than all the other quantitative SWE parameters. ALN evaluation in ultrasound and qualitative SWE were independent risk factors for predicting limited or high nodal burden according to a binary logistics regression analysis. The AUC of the predictive model based on independent risk factors was 0.820 (95% CI: 0.765-0.867), which was significantly higher than that of the other independent risk factors. Conclusions: The seven color patterns in the qualitative SWE of breast lesions were valuable for predicting limited or high nodal burden for patients with breast cancer. Compared with quantitative SWE, qualitative SWE exhibited a better diagnostic performance. Breast lesions present no findings, vertical stripes, and spot patterns were important indicators for limited nodal burden. The predictive model developed in this study could be a simple, noninvasive, and convenient method for predicting limited or high nodal burden, which would be beneficial for clinical decision-making and individual treatment to improve prognosis.

3.
Front Oncol ; 13: 1217309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965477

RESUMO

Objectives: To determine whether ultrasound radiomics can be used to distinguish axillary lymph nodes (ALN) metastases in breast cancer based on ALN imaging. Methods: A total of 147 breast cancer patients with 41 non-metastatic lymph nodes and 109 metastatic lymph nodes were divided into a training set (105 ALN) and a validation set (45 ALN). Radiomics features were extracted from ultrasound images and a radiomics signature (RS) was built. The Intraclass correlation coefficients (ICCs), Spearman correlation analysis, and least absolute shrinkage and selection operator (LASSO) methods were used to select the ALN status-related features. All images were assessed by two radiologists with at least 10 years of experience in ALN ultrasound examination. The performance levels of the model and radiologists in the training and validation subgroups were then evaluated and compared. Result: Radiomics signature accurately predicted the ALN status, achieved an area under the receiver operator characteristic curve of 0.929 (95%CI, 0.881-0.978) and area under curve(AUC) of 0.919 (95%CI, 95%CI, 0.841-0.997) in training and validation cohorts respectively. The radiomics model performed better than two experts' prediction of ALN status in both cohorts (P<0.05). Besides, prediction in subgroups based on baseline clinicopathological information also achieved good discrimination performance, with an AUC of 0.937, 0.918, 0.885, 0.930, and 0.913 in HR+/HER2-, HER2+, triple-negative, tumor sized ≤ 3cm and tumor sized>3 cm, respectively. Conclusion: The radiomics model demonstrated a good ability to predict ALN status in patients with breast cancer, which might provide essential information for decision-making.

4.
Sci Adv ; 9(12): eadf4651, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947616

RESUMO

Light modulates mood through various retina-brain pathways. We showed that mice treated with short-term acute bright light exposure displayed anxiety-related phenotypes in a prolonged manner even after the termination of the exposure. Such a postexposure anxiogenic effect depended upon melanopsin-based intrinsically photosensitive retinal ganglion cell (ipRGC) activities rather than rod/cone photoreceptor inputs. Chemogenetic manipulation of specific central nuclei demonstrated that the ipRGC-central amygdala (CeA) visual circuit played a key role in this effect. The corticosterone system was likely to be involved in this effect, as evidenced by enhanced expression of the glucocorticoid receptor (GR) protein in the CeA and the bed nucleus of the stria terminalis and by the absence of this effect in animals treated with the GR antagonist. Together, our findings reveal a non-image forming visual circuit specifically designed for "the delayed" extinction of anxiety against potential threats, thus conferring a survival advantage.


Assuntos
Núcleo Central da Amígdala , Células Ganglionares da Retina , Camundongos , Animais , Células Ganglionares da Retina/metabolismo , Retina , Células Fotorreceptoras Retinianas Cones , Células Fotorreceptoras de Vertebrados/metabolismo , Luz
5.
Sci Transl Med ; 14(674): eabq6474, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36475906

RESUMO

Green light exposure has been shown to reduce pain in animal models. Here, we report a vision-associated enkephalinergic neural circuit responsible for green light-mediated analgesia. Full-field green light exposure at an intensity of 10 lux produced analgesic effects in healthy mice and in a model of arthrosis. Ablation of cone photoreceptors completely inhibited the analgesic effect, whereas rod ablation only partially reduced pain relief. The analgesic effect was not modulated by the ablation of intrinsically photosensitive retinal ganglion cells (ipRGCs), which are atypical photoreceptors that control various nonvisual effects of light. Inhibition of the retino-ventrolateral geniculate nucleus (vLGN) pathway completely abolished the analgesic effects. Activation of this pathway reduced nociceptive behavioral responses; such activation was blocked by the inhibition of proenkephalin (Penk)-positive neurons in the vLGN (vLGNPenk). Moreover, green light analgesia was prevented by knockdown of Penk in the vLGN or by ablation of vLGNPenk neurons. In addition, activation of the projections from vLGNPenk neurons to the dorsal raphe nucleus (DRN) was sufficient to suppress nociceptive behaviors, whereas its inhibition abolished the green light analgesia. Our findings indicate that cone-dominated retinal inputs mediated green light analgesia through the vLGNPenk-DRN pathway and suggest that this signaling pathway could be exploited for reducing pain.


Assuntos
Corpos Geniculados , Manejo da Dor , Camundongos , Animais , Dor
6.
Dermatol Ther ; 35(8): e15657, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35726636

RESUMO

Axillary osmidrosis (AO) and primary hyperhidrosis (PH) are common diseases, but there are still difficulties in treatment. Microwave therapy may become a new method. In order to evaluate long-time efficacy of patients with AO or PH treated by microwave and to discuss possible mechanism of microwave therapy by combining results of clinical and pathological, the study was carried out. Ten AO or PH patients with moderate or severe level were selected as subjects, and each subject received microwave treatment of bilateral armpits. The follow-up period lasted 2 years, and the changes of perspiration and odor were evaluated in subjective and objective ways. Each subject took skin biopsy in the treatment area before and after treatment or each follow-up. Hematoxylin-eosin and immunohistochemical staining were performed. Both subjective and objective index reflected the significant improvement of AO and PH after treatment (p < 0.05). Dermatology life quality index score decreased by 10.4 ± 4.6 (p < 0.05). The number of apocrine glands decreased significantly after treatment, and most of them changed from secretory phase to quiescent phase. In conclusion, microwave therapy can destroy apocrine sweat glands, reduce number of functional glands, so as to improve symptoms of AO and PH and elevate quality of life, which is safe, effective, and stable.


Assuntos
Hiperidrose , Micro-Ondas , Axila/patologia , Humanos , Hiperidrose/diagnóstico , Hiperidrose/radioterapia , Micro-Ondas/efeitos adversos , Qualidade de Vida , Resultado do Tratamento
7.
Organogenesis ; 17(3-4): 27-39, 2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34965835

RESUMO

Cardiac hypertrophy contributes to heart failure and is pathogenically modulated by a network of signaling cascades including Wnt/ß-catenin signaling pathway. miRNAs have been widely demonstrated to regulate gene expression in heart development. miR-128 was routinely found as a brain-enriched gene and has been functionally associated with regulation of cardiac function. However, its role and molecular mechanisms that regulate cardiac hypertrophy remain largely unclear. Adeno-associated virus serotype 9 (AAV9)-mediated constructs with miR-128 or anti-miR-128 were generated and delivered to overexpression or blockade of miR-128 in vivo followed by HF induction with isoproterenol (ISO) or transverse aortic constriction (TAC). Cardiac dysfunction and hypertrophy, coupled with involved gene and protein level, were then assessed. Our data found that miR-128, Wnt1, and ß-catenin expressions were upregulated in both patients and mice model with HF. Interference with miR-128 reduces Wnt1/ß-catenin expression in mouse failing hearts and ameliorates heart dysfunctional properties. We identified miR-128 directly targets to Axin1, an inhibitor of Wnt/ß-catenin signaling, and suppresses its inhibition on Wnt1/ß-catenin. Our study provides evidence indicating miR-128 as an inducer of HF and cardiac hypertrophy by enhancing Wnt1/ß-catenin in an Axin1-dependent nature. We thus suggest miR-128 has potential value in the treatment of heart failure.


Assuntos
Insuficiência Cardíaca , Traumatismos Cardíacos , MicroRNAs , Animais , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Humanos , Camundongos , MicroRNAs/metabolismo , Regulação para Cima , Via de Sinalização Wnt/fisiologia
8.
Anesthesiology ; 133(1): 165-184, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32349075

RESUMO

BACKGROUND: Brain-derived estrogen is implicated in pain-related aversion; however, which estrogen receptors mediate this effect remains unclear. This study hypothesized that the different estrogen receptors in the rostral anterior cingulate cortex play distinct roles in pain-related aversion. METHODS: Formalin-induced conditioned place avoidance and place escape/avoidance paradigms were used to evaluate pain-related aversion in rodents. Immunohistochemistry and Western blotting were used to detect estrogen receptor expression. Patch-clamp recordings were used to examine N-methyl-D-aspartate-mediated excitatory postsynaptic currents in rostral anterior cingulate cortex slices. RESULTS: The administration of the estrogen receptor-ß antagonist 4-(2-phenyl-5,7-bis [trifluoromethyl] pyrazolo [1,5-a] pyrimidin-3-yl) phenol (PHTPP) or the G protein-coupled estrogen receptor-1 antagonist (3aS*,4R*,9bR*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-3H-cyclopenta [c] quinolone (G15) but not the estrogen receptor-α antagonist 1,3-bis (4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy) phenol]-1H-pyrazole dihydrochloride (MPP) into the rostral anterior cingulate cortex blocked pain-related aversion in rats (avoidance score, mean ± SD: 1,3-bis [4-hydroxyphenyl]-4-methyl-5-(4-[2-piperidinylethoxy] phenol)-1H-pyrazole dihydrochloride (MPP): 47.0 ± 18.9%, 4-(2-phenyl-5,7-bis [trifluoromethyl] pyrazolo [1,5-a] pyrimidin-3-yl) phenol (PHTPP): -7.4 ± 20.6%, and [3aS*,4R*,9bR*]-4-[6-bromo-1,3-benzodioxol-5-yl]-3a,4,5,9b-3H-cyclopenta [c] quinolone (G15): -4.6 ± 17.0% vs. vehicle: 46.5 ± 12.2%; n = 7 to 9; P < 0.0001). Consistently, estrogen receptor-ß knockdown but not estrogen receptor-α knockdown by short-hairpin RNA also inhibited pain-related aversion in mice (avoidance score, mean ± SD: estrogen receptor-α-short-hairpin RNA: 26.0 ± 7.1% and estrogen receptor-ß-short-hairpin RNA: 6.3 ± 13.4% vs. control short-hairpin RNA: 29.1 ± 9.1%; n = 7 to 10; P < 0.0001). Furthermore, the direct administration of the estrogen receptor-ß agonist 2,3-bis (4-hydroxyphenyl)-propionitrile (DPN) or the G protein-coupled estrogen receptor-1 agonist (±)-1-([3aR*,4S*,9bS*]-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta [c]quinolin-8-yl)-ethanone (G1) into the rostral anterior cingulate cortex resulted in conditioned place avoidance (avoidance score, mean ± SD: 2,3-bis (4-hydroxyphenyl)-propionitrile (DPN): 35.3 ± 9.5% and (±)-1-([3aR*,4S*,9bS*]-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta [c]quinolin-8-yl)-ethanone (G1): 43.5 ± 22.8% vs. vehicle: 0.3 ± 14.9%; n = 8; P < 0.0001) but did not affect mechanical or thermal sensitivity. The activation of the estrogen receptor-ß/protein kinase A or G protein-coupled estrogen receptor-1/protein kinase B pathway elicited the long-term potentiation of N-methyl-D-aspartate-mediated excitatory postsynaptic currents. CONCLUSIONS: These findings indicate that estrogen receptor-ß and G protein-coupled estrogen receptor-1 but not estrogen receptor-α in the rostral anterior cingulate cortex contribute to pain-related aversion by modulating N-methyl-D-aspartate receptor-mediated excitatory synaptic transmission.


Assuntos
Giro do Cíngulo/fisiopatologia , Dor/fisiopatologia , Dor/psicologia , Receptores de Estrogênio , Animais , Aprendizagem da Esquiva , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/genética , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Antagonistas de Estrogênios/farmacologia , Receptor beta de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/genética , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/genética
9.
Nanoscale ; 10(45): 21106-21115, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30325397

RESUMO

The rediscovery of black phosphorus (BP) has expanded the 2D family into Group 15 (Nitrogen Group) elements, among which bismuthene is the latest member with extraordinary opto-electronic, catalytic and biocompatible properties and potential as a 2D topological insulator. However, bulk Bi is not easily mechanically exfoliated as its counterpart of BP. Thus, to date, the reports on 2D Bi fabrication are rare, and investigations on its nonlinear optical properties are even less. Herein, we rationally designed a new strategy combining acid-interaction and liquid exfoliation to successfully transform metal bulk Bi into few-layer semiconductor, which resulted in unseen opto-electronic properties, such as tunable nonlinear responses all the way to the near-infrared (NIR) region. This band is critical for telecommunication and military purposes, but currently, functioning materials are extremely scarce. The origin of this strong saturable absorption was thoroughly explored through time-resolved spectroscopy spanning from the fs to µs timescale, which indicated ultrafast fs to ps carrier dynamics in the early stage and long exciton bleaching recovery up to µs. As a proof-of-concept application, the as-prepared 2D Bi was employed as a saturable absorber to mode-lock a Tm-doped fiber laser and successfully realized a 2 µm NIR-wavelength output. This study not only offers an effective and scalable method to fabricate the new 2D family member bismuthene with extraordinary stability, but also explores its strong and broad nonlinear responses extending into the NIR region and fundamental photoinduced dynamics, which demonstrate the full potential of 2D Bi for application in opto-electronic devices and nonlinear optics.

10.
Sheng Li Xue Bao ; 69(5): 637-646, 2017 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-29063111

RESUMO

The pain experience includes a sensory-discriminative component and an emotional-affective component. The great progress in the genetic, molecular, cellular and systemic levels on the study of the sensory dimension of pain has been made. However, the study of the emotional components of pain is relatively backward. A line of clinic observations indicates that chronic pain and pain-related negative emotion affect the physical and mental health of patients. This review summarizes the main progress from our and other laboratories regarding the affective component of pain, elaborates the neuronal mechanisms of pain-related aversive emotion in the anterior cingulate cortex (ACC), especially the critical role of NMDA receptors and ERK-CREB pathway. A variety of regulatory molecules, such as synapse associated protein SIP30 and estrogen contribute to pain-related aversive emotion via facilitating presynaptic glutamate release and postsynaptic NMDA receptor-mediated synaptic transmission. The far-reaching effects of pain-related negative emotion on patients with chronic pain are emphasized.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Emoções , Giro do Cíngulo/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Dor/psicologia , Receptores de N-Metil-D-Aspartato/fisiologia , Transdução de Sinais/fisiologia , Animais , Humanos
11.
Asian Pac J Cancer Prev ; 16(17): 7871-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26625813

RESUMO

BACKGROUND: There is no consensus regarding the selection of treatment options for hepatocellular carcinoma (HCC) after initial transarterial chemoembolization (TACE). This meta-analysis aimed to explore the survival benefit of hepatic resection after initial TACE for the treatment of HCC. MATERIALS AND METHODS: We searched three major databases to identify all relevant papers comparing the outcomes of hepatic resection after initial TACE versus TACE alone for the treatment of HCC. Hazard ratios (HRs) with 95% confidence intervals (95%CIs) were calculated to evaluate the survival benefit of hepatic resection after initial TACE over TACE alone. RESULTS: Three of 2,037 initially identified papers were included. All of them were cohort studies from Asia. There was a significantly better overall survival (OS) in patients undergoing hepatic resection after initial TACE than in those undergoing TACE alone (HR=0.63, 95%CI=0.52-0.76, P<0.00001). The heterogeneity among studies was not statistically significant (P=0.96; I2=0%). CONCLUSIONS: Hepatic resection could improve the OS of HCC patients treated initial TACE. Further randomized controlled trials are now necessary to identify the target populations for the sequential use of hepatic resection after initial TACE and to compare the outcomes between patients undergoing hepatic resection after initial TACE session versus those undergoing TACE alone.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Quimioembolização Terapêutica , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Terapia Combinada/métodos , Feminino , Humanos , Fígado/patologia , Fígado/cirurgia , Masculino , Resultado do Tratamento
12.
Clin Oral Implants Res ; 26(2): 204-11, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24330035

RESUMO

OBJECTIVE: To evaluate the long-term outcomes of ridge expansion technique in dealing with horizontal bony insufficiency of alveolar ridges for implant placement. MATERIALS AND METHODS: During the period 2004-2009, 168 patients with width insufficiency of alveolar ridges were treated using the ridge expansion technique to obtain an improved bony base for implant placement. Depending on the severity of width insufficiency, the surgical procedures were classified into two groups: ridge expansion alone (Group 1) and ridge expansion in combination with guided bone regeneration (Group 2). After 4-6 months of unloaded healing, the implants were restored. The patients were followed up until 2013 with clinical and radiographic examinations. RESULTS: Among the 168 patients, 11 patients underwent a fracture of labial/buccal bony plate during surgery, which was corrected by changing the procedure into bone grafting, yielding a surgical failure rate of 6.5%. In the remaining 157 patients successfully treated by ridge expansion alone or in combination with GBR, 226 implants were simultaneously placed as planned. No implant failed over 2.8 years (6 months to 8 years) of follow-up, yielding a cumulative implant survival rate of 100% in each group. Six implants in Group 1 and 4 implants in Group 2, although osseointegrated and in function, did not fulfill success criteria: Cumulative implants' success rates were 93.2% in Group 1 and 95.6% in Group 2. The mean marginal bone losses during the first year in Group 1 and Group 2 were 0.69 and 0.43 mm, respectively, followed by an annual loss of ~ 0.06 and 0.07 mm, respectively, in the following years. No clinical parameter was abnormal. Twenty-two (10.4%) implants were exposed to peri-implant mucositis, whereas 19 (11.0%) implant-supported restorations were involved in prosthetic complications. CONCLUSIONS: The preliminary results of this retrospective study indicate that ridge expansion alone or in combination with GBR can be considered an effective and safe procedure for treatment of width insufficiency of alveolar ridges on the purpose of implant application.


Assuntos
Perda do Osso Alveolar/cirurgia , Aumento do Rebordo Alveolar/métodos , Implantação Dentária Endóssea/métodos , Implantes Dentários , Regeneração Tecidual Guiada Periodontal , Adulto , Perda do Osso Alveolar/diagnóstico por imagem , Processo Alveolar , Aumento do Rebordo Alveolar/efeitos adversos , Transplante Ósseo , Feminino , Seguimentos , Humanos , Arcada Parcialmente Edêntula/cirurgia , Masculino , Fraturas Mandibulares/cirurgia , Pessoa de Meia-Idade , Osseointegração , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
Clin Oral Implants Res ; 26(6): 615-22, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24611966

RESUMO

OBJECTIVES: To establish and experimentally validate a novel resonance frequency analysis (RFA) method for measurement of dental implant stability by analyzing torsional resonance frequency (TRF). MATERIAL AND METHODS: A numerical study and in vitro measurements were performed to evaluate the feasibility and reliability of the method of torsional RFA (T-RFA) using a T-shaped bilateral cantilever beam transducer. The sensitivity of this method was assessed by measuring the TRFs of dental implants with 8 sizes of T-shaped transducers during polymerization, which simulated the process of bone healing around an implant. The TRFs of the test implants detected using this new method and the bending resonance frequencies (BRFs) measured by Osstell(®) ISQ were compared. TRFs and BRFs on implant models in polymethyl methacrylate (PMMA) blocks with three exposure heights were also measured to assess the specificity of this method. RESULTS: Finite element analysis showed two bending modes (5333 and 6008 Hz) following a torsional mode (8992 Hz) in the lower rank frequency. During in vitro measurements, a bending formant (mean 6075 Hz) and a torsional formant (mean 10225 Hz) appeared, which were verified by multipoint measurement with invariable excitation frequency in the laboratory. In the self-curing resin experiments, the average growth rate at all time points of TRFs using the new method with Transducer II was 2.36% and that of BRFs using Osstell(®) ISQ was 1.97%. In the implant exposure height tests, the mean declined rate of TRFs was 2.06% and that of BRFs using Osstell(®) ISQ was 12.34%. CONCLUSION: A novel method for assessment of implant stability through TRF was established using a T-shape transducer, which showed high reliability and sensibility. The method alleviated the effects of implant exposure height on the measurements compared with Osstell(®) ISQ. The application of T-RFA represents another way in the investigation of dental implant osseointegration.


Assuntos
Implantes Dentários , Retenção em Prótese Dentária , Torção Mecânica , Vibração , Implantação Dentária Endóssea/métodos , Planejamento de Prótese Dentária , Humanos , Osseointegração/fisiologia , Polimetil Metacrilato/química
14.
Opt Express ; 21(14): 17359-65, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23938582

RESUMO

We report the first laser operation based on Ho(3+)-doped LuLiF(4) single crystal, which is directly pumped with 1.15-µm laser diode (LD). Based on the numerical model, it is found that the "two-for-one" effect induced by the cross-relaxation plays an important role for the laser efficiency. The maximum continuous wave (CW) output power of 1.4 W is produced with a beam propagation factor of M(2) ~2 at the lasing wavelength of 2.066 µm. The slope efficiency of 29% with respect to absorbed power is obtained.


Assuntos
Lasers de Estado Sólido , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(4): 653-7, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16836132

RESUMO

Raman spectroscopy was used to investigate the effect of different intervals of ultraviolet (UV) to calf thymus DNA in aqueous solution. At the same time, the different influences of these three UV parts were compared, and a complete damaging mechanism of UV to DNA was obtained. The results showed that UVC damages DNA in a complete way, while UVA and UVB damage DNA in a selective way, and the speed effect of UVB on DNA was faster than that of UVA. UVC seemed to be less valid in reducing the B conformation of DNA than UVA and UVB. Among all the groups of DNA, the pyrimidine bases and the deoxyribose experienced the most severe damages. Moreover, with UVA or UVB irradiation for 3 h, the photoreactivation of DNA occured. The experimental results partly supported the formation of several types of dimeric lesions between adjacent pyrimidine bases, most notably cyclobutane pyrimidine dimers (CPD), 6-4 photoproducts (6-4PP) and the Dewar valence isomers.


Assuntos
Dano ao DNA/efeitos da radiação , DNA/química , DNA/genética , Análise Espectral Raman/métodos , Animais , Reparo do DNA/efeitos da radiação , Fatores de Tempo , Raios Ultravioleta
16.
Acta Biochim Biophys Sin (Shanghai) ; 37(1): 39-46, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15645080

RESUMO

Raman spectroscopy was used for the first time to detect the effect of independent UVA (ultraviolet-A: 320-400 nm) and UVB (ultraviolet-B: 280-320 nm) irradiation on the calf thymus DNA in aqueous solution. After both UVA and UVB irradiation for 1 h or 3 h, the damage to the conformation of DNA was moderate, but the reduction of the B-form DNA component was obvious. Both UVA and UVB caused significant damage to the deoxyribose moiety and bases, among which the pyrimidine base pairs were more seriously affected. There appeared to be preferential damaging sites on DNA molecules caused by UVA and UVB irradiation. UVA irradiation caused more damage to the deoxyribose than UVB irradiation, while UVB irradiation caused more significant damage to the pyrimidine moiety than UVA irradiation. After UVB irradiation for 3 h, unstacking of the AT base pairs and the cytosine ring took place, severe damage to the thymine moiety occurred, and some base pairs were modified. Moreover, with either UVA or UVB irradiation for 3 h, the photoreactivation of DNA occurred. The damage to the DNA caused by UVB was immediate, while the damage caused by UVA was proportional to the irradiation duration. The experimental results partly indicate the formation of some cyclobutane pyrimidine dimers and (6-4) photoproducts.


Assuntos
DNA/genética , DNA/efeitos da radiação , Análise Espectral Raman/métodos , Timo/metabolismo , Animais , Bovinos , DNA/química , DNA/metabolismo , Pirimidinas/química , Fatores de Tempo , Raios Ultravioleta
17.
Zhonghua Nei Ke Za Zhi ; 43(12): 907-10, 2004 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-15730735

RESUMO

OBJECTIVE: To investigate blood pressure-lowering effect of rosiglitazone in overweight/obese non-diabetic patients with hypertension to explore the therapeutic role of insulin sensitizers in the management of essential hypertension. METHODS: 89 cases of overweight/obese non-diabetics with essential hypertension were enrolled in a 4 weeks open label clinical trial. Rosiglitazone 8 mg/day were started 2 weeks after withdrawing previously used anti-hypertensive medications. Blood pressure was measured at the 2nd and 4th week. Plasma glucose and insulin levels during oral glucose tolerance test (OGTT) at baseline and at 4th week were also determined. RESULTS: After 4 weeks treatment with rosiglitazone, the mean systolic and diastolic blood pressure reduced by 17 mm Hg (1mm Hg = 0.133 kPa) and 11 mm Hg, respectively. Plasma insulin levels at fasting, 1 and 2 hour during OGTT decreased by 27%, 35% and 41%, respectively (P < 0.001), whereas insulin sensitivity increased by 30% (P < 0.001). The amplitude of reduction of blood pressure was related to the baseline level of blood pressure and insulin sensitivity, and family history of hypertension. CONCLUSIONS: Rosiglitazone significantly reduces blood pressure in overweight and/or obese non-diabetic subjects with hypertension. Randomized controlled clinical trial is justified to confirm the therapeutic role of rosiglitazone in the management of non-diabetic essential hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Resistência à Insulina , Tiazolidinedionas/uso terapêutico , Adulto , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Feminino , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Obesidade , Rosiglitazona
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