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1.
Small ; 20(11): e2309454, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38098368

RESUMO

The optimal treatment for tracheal tumors necessitates sequential tumor elimination and tracheal cartilage reconstruction. This study introduces an innovative inorganic nanosheet, MnO2 /PDA@Cu, comprising manganese dioxide (MnO2 ) loaded with copper ions (Cu) through in situ polymerization using polydopamine (PDA) as an intermediary. Additionally, a specialized methacrylic anhydride modified decellularized cartilage matrix (MDC) hydrogel with chondrogenic effects is developed by modifying a decellularized cartilage matrix with methacrylic anhydride. The MnO2 /PDA@Cu nanosheet is encapsulated within MDC-derived microneedles, creating a photothermal-controllable MnO2 /PDA@Cu-MDC microneedle. Effectiveness evaluation involved deep insertion of the MnO2 /PDA@Cu-MDC microneedle into tracheal orthotopic tumor in a murine model. Under 808 nm near-infrared irradiation, facilitated by PDA, the microneedle exhibited rapid overheating, efficiently eliminating tumors. PDA's photothermal effects triggered controlled MnO2 and Cu release. The MnO2 nanosheet acted as a potent inorganic nanoenzyme, scavenging reactive oxygen species for an antioxidant effect, while Cu facilitated angiogenesis. This intervention enhanced blood supply at the tumor excision site, promoting stem cell enrichment and nutrient provision. The MDC hydrogel played a pivotal role in creating a chondrogenic niche, fostering stem cells to secrete cartilaginous matrix. In conclusion, the MnO2 /PDA@Cu-MDC microneedle is a versatile platform with photothermal control, sequentially combining antitumor, antioxidant, pro-angiogenic, and chondrogenic activities to orchestrate precise tracheal tumor eradication and cartilage regeneration.


Assuntos
Nanopartículas , Neoplasias , Neoplasias da Traqueia , Humanos , Camundongos , Animais , Antioxidantes , Compostos de Manganês , Óxidos , Neoplasias/patologia , Cartilagem , Hidrogéis , Anidridos
2.
Zhonghua Yi Xue Za Zhi ; 102(34): 2647-2650, 2022 Sep 13.
Artigo em Zh | MEDLINE | ID: mdl-36096692

RESUMO

Airway mucus plug is an important clinical feature of bronchial asthma and is related to the prognosis of the disease. Clinically, chest CT is a preferred tool for evaluating airway mucus plugs. At present, the interpretation of CT images relies on manual reading, but the airway mucus plugs of patients with bronchial asthma are mostly distributed in the small and medium airways, which are difficult to identify with the naked eye. In recent years, with the continuous progress of deep learning and big data technology, artificial intelligence (AI)-assisted image reading technology has been introduced into clinical application, which has significantly improved the efficiency and accuracy of mucus plug identification. Currently, AI-assisted airway mucus plug identification has been used in respiratory diseases such as cystic fibrosis, chronic obstructive pulmonary disease, and bronchial asthma. Therefore, the application of AI counting to mucus plugs in patients with bronchial asthma is of great significance.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Inteligência Artificial , Humanos , Muco , Tomografia Computadorizada por Raios X
3.
Opt Express ; 28(9): 12805-12826, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403770

RESUMO

Chip-based optical beam scanners hold promise for future compact high-speed light detection and ranging (LIDAR) systems. Many of the demonstrated chip-based optical beam scanners are designed based on diffraction-based waveguide gratings as on-chip antennas. The waveguide grating antenna, however, only provides a typical field-of-view (FOV) of roughly 10° by tuning the input light wavelength. In this paper, polarization-division and spatial-division multiplexed nanoantenna arrays are proposed to expand the FOV of on-chip antennas. The proposed device, based on silicon-on-insulator (SOI) platform, consists of three nanoantenna groups which are densely packed and fed by a common silicon nanostrip. It is demonstrated that the combination of the optical mode-multiplexing technique and the antenna engineering allows independent controls over the interactions between multiple nanoantenna groups and the waveguide. By proper engineering of the antenna dimensions, the proposed device achieves a FOV of over 40° within a 100 nm wavelength tuning range, almost tripling that of the conventional waveguide grating antenna.

4.
Zhonghua Yi Xue Za Zhi ; 99(36): 2836-2839, 2019 Sep 24.
Artigo em Zh | MEDLINE | ID: mdl-31550812

RESUMO

Objective: To explore the significance of prostate central gland/total gland volume (PVc/PV) ratio combined with PSA in the diagnosis of PSA 4-20 ng/ml prostate cancer patients. Methods: Data of patients undergoing prostate puncture in Minghang Branch, Zhongshan Hospital from July 2015 to December 2018 were retrospectively analyzed. The anteroposterior, transverse and axial diameters of the prostate and the central prostate gland were measured by magnetic resonance imaging (MRI). The differences of tPSA, f/tPSA, PSAD and PVc/PV between the prostate cancer group and non-prostate cancer group were compared. Receiver operating characteristic (ROC) curves of prostate cancer diagnosis were plotted according to tPSA, f/tPSA, PSAD, PVc/PV alone and PVc/PV combined with tPSA, respectively, and the area under the curve (AUC) was calculated and compared using tPSA as the reference. Results: There was no significant difference in tPSA between the two groups (P>0.05). However, significant differences were observed in f/tPSA, PSAD and PVc/PV between the two groups (P<0.05). The AUC value of PVc/PV combined with tPSA, PVc/PV and PSAD was 0.901 2,0.866 7 and 0.848 1,respectively, which were statistically different from that of tPSA (P<0.05). The AUC value of f/tPSA was 0.716, which was not statistically different from that of tPSA (P>0.05). Conclusion: The PVc/PV ratio combined with tPSA can be used as an important reference index for the diagnosis of prostate cancer in PSA 4-20 ng/ml patients.


Assuntos
Neoplasias da Próstata , Humanos , Masculino , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Zhonghua Jie He He Hu Xi Za Zhi ; 42(3): 213-218, 2019 Mar 12.
Artigo em Zh | MEDLINE | ID: mdl-30845399

RESUMO

Objective: To assess the quality of the clinical practice guideline for diagnosis, treatment and prevention of pulmonary thromboembolism, 2018 in China, providing the references for updating and developing clinical practice guidelines of this field in the future. Methods: The quality of the clinical practice guideline for diagnosis, treatment and prevention of pulmonary thromboembolism, 2018 in China was assessed using the internationally recognized instrument Appraisal of Guidelines for Research and Evaluation Ⅱ (AGREE Ⅱ). AGREE Ⅱ instrument consisted of 23 items in six domains, followed by two overall assessment items. Each item was scored from 1 to 7. The final overall guideline quality considered all domain items. Results: The scores of the six AGREE Ⅱ domains were: Scope and purpose 76.4%, Stakeholder involvement 55.6%, Rigor of development 78.1%, Clarity and presentation 83.3%, Applicability 55.2%, and Editorial independence 66.7%. The guideline was recommended for clinical use. Among the 101 recommendations, recommendations based on Levels High, Moderate and Low evidence accounted for 7 (6.9%), 31 (30.7%) and 63 (62.4%), respectively. Conclusion: The methodological quality of the clinical practice guideline for diagnosis, treatment and prevention of pulmonary thromboembolism, 2018 in China was great, but the levels of evidence were not high. More efforts were urgently required to improve in Stakeholder involvement and applicability. Especially corresponding economic research evidence, as well as preferences of patients and the public should be considered in the future development of clinical practice guidelines.


Assuntos
Guias de Prática Clínica como Assunto/normas , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/prevenção & controle , Embolia Pulmonar/terapia , Qualidade da Assistência à Saúde/normas , China , Medicina Baseada em Evidências , Humanos
6.
Zhonghua Yi Xue Za Zhi ; 98(38): 3084-3086, 2018 Oct 16.
Artigo em Zh | MEDLINE | ID: mdl-30392268

RESUMO

Objective: To investigate the safety and feasibility of retroperitoneal laparoscopic nephron-sparing surgery (NSS) in stage T(1b) renal cell carcinoma (RCC) patients . Methods: Between March 2014 and June 2017, 52 stage T(1b) RCC cases (36 males, 16 females) treated with retroperitoneal laparoscopic NSS in Zhongshan Hospital and Central Hospital of Minhang District were enrolled and retrospectively analyzed, with a tumor size range of 4.0 to 6.8 cm, and a mean size of(4.7±0.45)cm.The anatomic characteristics of tumors, operative time, intra-operative blood loss, warm ischemia time, intra- and post-operative complications, length of hospital stay, and oncological outcomes were reviewed. Results: Only 2 cases converted to open surgery due to uncontrollable bleeding in operation. The rest 50 cases successfully underwent retroperitoneal laparoscopic NSS, with mean operative time of (122±20.86) min (range: 100-220 min), mean blood loss of (140±128.85)ml (range: 50-800 ml), mean warm ischemia time of (30±3.52)min (range: 25-42 min), pre-operative mean serum creatinine of (100±23.54)µmol/L (range: 65-148 µmol/L), mean serum creatinine three monthsafter operation of (104±30.84)µmol/L (range: 72-224 µmol/L), mean drainage of (180±82.33)ml (range: 80-550 ml), mean length of hospital stay after operation of (8±1.56)d (range: 5-15 d). There was no significant difference in renal function between pre- and post-operation (P=0.056). One patient suffered pulmonary embolism was cured conservatively. Fifty patients were followed up, among which 47 cases with malignant pathology were followed up for 3-29 months, and two of them suffered from pulmonary metastasis. Conclusions: After pre-operative comprehensive assessment of tumors, stage T(1b) renal cell carcinoma could be treated with retroperitoneal laparoscopic NSS safely.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais/cirurgia , Nefrectomia , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Laparoscopia , Masculino , Néfrons , Estudos Retrospectivos
7.
Phys Chem Chem Phys ; 18(11): 7875-87, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26911420

RESUMO

We investigate the photophysical properties of organic donor-acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units linked by a non-conjugated flexible bridge in solution using complementary optical spectroscopy techniques. When these molecules are diluted in dichloromethane solution, energy transfer from the triphenylene to the perylene diimide excited moieties is evidenced by time-resolved fluorescence measurements resulting in a quenching of the emission from the triphenylene moieties. Simultaneously, another quenching process that affects the emission from both donor and acceptor units is observed. Solution ultrafast transient absorption measurements provide evidence of photo-induced charge transfer from either the donor or the acceptor depending upon the excitation. Overall, the analysis of the detailed time-resolved spectroscopic measurements carried out in the dyad and triad systems as well as in the triphenylene and perylene diimide units alone provides useful information both to better understand the relations between energy and charge transfer processes with molecular structures, and for the design of future functional dyad and triad architectures based on donor and acceptor moieties for organic optoelectronic applications.

8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(1): 683-5, 2016 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-27538152

RESUMO

OBJECTIVE: To analyze the reasons of early failure of the PHILOS in proximal humerus fractures. METHODS: From Nov. 2010 to Nov. 2014, there were 117 patients with humerus fractures treated with PHILOS locking plate in Department of Orthopaedics, Xuanwu Hospital. All of the patients were treated with the plate by open reduction internal fixation, and we analyzed these cases retrospectively. After the operation, we removed the drainage tube within 48 h, and the patients were allowed to do the passive motion 3 days after the surgery if the X-Ray showed the plate and screws were reliable. Eight cases failed within 4 weeks after the operation. We analyzed the reasons of the failure. RESULTS: The rate of the failed cases was 6.83%(8/117). The average age was 72.4(66-82) years. In the 8 failed cases, 3 were on the right side, and the other 5 on the left side. As for the reason of the fractures, 2 cases were because of car accidents, and the other 6 because of daily life injury. According to the Neer classification, 3 cases were 2-part fractures, and the other 5 3-part fractures. Three cases were total failure, and the other 5 partial failure. All the 8 failed cases failed within 4 weeks after the operation, of which 1 was on the sixth day after surgery, the other 7 2 to 4 weeks after the surgery.The 3 totally failed cases were treated by removing the screws and plates, the other 5 by conservative methods. All of the cases were malunion at the end. CONCLUSION: The early failure of the PHILOS locking plate in proximal humerus fractures is related to the bad reduction during the operation, the loss of medial cortex support, the limitation of screw length, the osteoporosis and the improper rehabilitation after operation.It is very important to do good preoperative plan for a surgeon. During the operation, we should try our best in the fracture reduction, use the appropriate plate and screws, and then pay attention to the rehabilitation after the operation. After all of this, the rate of failure may be decreased.

9.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(4): 683-685, 2016 Aug 18.
Artigo em Zh | MEDLINE | ID: mdl-29263513

RESUMO

OBJECTIVE: To analyze the reasons of early failure of the PHILOS in proximal humerus fractures. METHODS: From Nov. 2010 to Nov. 2014, there were 117 patients with humerus fractures treated with PHILOS locking plate in Department of Orthopaedics, Xuanwu Hospital. All of the patients were treated with the plate by open reduction internal fixation, and we analyzed these cases retrospectively. After the operation, we removed the drainage tube within 48 h, and the patients were allowed to do the passive motion 3 days after the surgery if the X-Ray showed the plate and screws were reliable. Eight cases failed within 4 weeks after the operation. We analyzed the reasons of the failure. RESULTS: The rate of the failed cases was 6.83%(8/117). The average age was 72.4(66-82) years. In the 8 failed cases, 3 were on the right side, and the other 5 on the left side. As for the reason of the fractures, 2 cases were because of car accidents, and the other 6 because of daily life injury. According to the Neer classification, 3 cases were 2-part fractures, and the other 5 3-part fractures. Three cases were total failure, and the other 5 partial failure. All the 8 failed cases failed within 4 weeks after the operation, of which 1 was on the sixth day after surgery, the other 7 2 to 4 weeks after the surgery.The 3 totally failed cases were treated by removing the screws and plates, the other 5 by conservative methods. All of the cases were malunion at the end. CONCLUSION: The early failure of the PHILOS locking plate in proximal humerus fractures is related to the bad reduction during the operation, the loss of medial cortex support, the limitation of screw length, the osteoporosis and the improper rehabilitation after operation.It is very important to do good preoperative plan for a surgeon. During the operation, we should try our best in the fracture reduction, use the appropriate plate and screws, and then pay attention to the rehabilitation after the operation. After all of this, the rate of failure may be decreased.


Assuntos
Fixação Interna de Fraturas , Fraturas do Úmero/cirurgia , Fraturas do Ombro/cirurgia , Idoso , Idoso de 80 Anos ou mais , Placas Ósseas , Parafusos Ósseos , Feminino , Humanos , Úmero , Masculino , Redução Aberta , Osteoporose , Radiografia , Estudos Retrospectivos
10.
Genet Mol Res ; 14(4): 17916-26, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26782437

RESUMO

To identify genes of potential importance to alkalinity tolerance, RNA sequencing (RNA-Seq) was performed to survey gill transcriptome profiles from freshwater (FW) and alkaline water (AW) exposed Nile tilapia (Oreochromis niloticus). A total of 22,724,036 (AW)/16,461,040 (FW) single-end reads were generated in which 20,304,348 (AW)/14,681,290 (FW) reads (90.0/89.72%) were aligned to the reference genome. Differential expression analysis revealed 302 up-regulated and 193 down-regulated genes between AW- and FW-exposed fish. These differentially expressed genes were enriched in several Gene Ontology (GO) terms related to "stress response", "heme binding", and "carbonate dehydratase activity". Meanwhile, significant KEGG pathways were enriched in energy metabolism, including nitrogen and sulfur metabolism. These results demonstrate the response of Nile tilapia exposed to alkaline-water and might provide valuable information to further understand the molecular mechanisms of adaptation of fish to alkaline environments.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Tilápia/genética , Transcriptoma/genética , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Álcalis/toxicidade , Animais , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
11.
Genet Mol Res ; 14(4): 12386-93, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26505388

RESUMO

Intervertebral disc degeneration is the main cause of lumbago disease, in which the extracellular matrix structure and moisture in the nucleus pulposus is lost continuously. In this study, we aimed to detect differential expression of silence mating type information regulation 2 homolog 1 (SIRT1) and matrix metalloproteinase-1 (MMP-1) in human intervertebral disc nucleus pulposus cells and to explore the effects of SIRT1 and MMP-1 on the development of the intervertebral disc degeneration. Intervertebral disc nucleus pulposus specimens from 41 patients who underwent lumbar protrusion resection at HuiZhou Municipal Central Hospital, during the period from October 2011 to December 2013, were studied in comparison with 23 control cases from patients who underwent fractured lumbar resection. In degenerated human intervertebral disc nucleus pulposus cells, the expression of SIRT1 is decreased and MMP-1 is increased compared with that of the control cells. Resveratrol could reverse these effects, thereby increasing the expression of SIRT1 (0.87 ± 0.07 vs 0.54 ± 0.04), Coll2α1 (0.90 ± 0.08 vs 0.38 ± 0.01), and aggrecan (0.69 ± 0.07 vs 0.42 ± 0.05) and decreasing the expression of MMP-1 (0.61 ± 0.03 vs 0.93 ± 0.08). These results suggest that resveratrol could possibly reverse the process of intervertebral disc degeneration and thus could be applied as a potential drug for the disease.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Metaloproteinase 1 da Matriz/genética , Sirtuína 1/genética , Estilbenos/farmacologia , Adulto , Idoso , Agrecanas/metabolismo , Células Cultivadas , Colágeno Tipo II/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Resveratrol , Sirtuína 1/metabolismo , Adulto Jovem
12.
Opt Express ; 22(17): 20816-27, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25321285

RESUMO

Electro-optic switching of refraction is experimentally demonstrated in a phase-discontinuity complementary metasurface twisted nematic cell. The phase-discontinuity complementary metasurface is fabricated by focused-ion-beam milling, and a twisted nematic cell is constructed with complementary V-shape slot antenna metasurface. By application of an external voltage, switching is achieved between ordinary refraction and extraordinary refraction satisfying the generalized Snell's law. It has a strong implication for applications in spatial light modulation and wavelength division multiplexer/demultiplexer in a near-IR spectral range.

13.
Phys Chem Chem Phys ; 16(32): 16941-56, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25005146

RESUMO

We investigate the photophysical and amplified spontaneous emission properties of a series of monodisperse solution-processable oligofluorenes functionalized with hexyl chains at the C9 position of each fluorene unit. Thin films of these oligofluorenes are then used in organic field-effect transistors and their charge transport properties are examined. We have particularly focused our attention on the influence of oligofluorene length on the absorption and steady-state fluorescence spectra, on the HOMO/LUMO energy levels, on the photoluminescence lifetime and quantum yield as well as on the amplified spontaneous emission properties and the charge carrier mobilities. Differential scanning calorimetry and X-ray diffraction measurements demonstrate that, among all oligofluorene derivatives used in this study, only the structure and morphology of the pentafluorene film is significantly modified by a thermal treatment above the glass transition temperature, resulting in a 9 nm blue-shift of the fluorescence spectrum without significant changes in the photoluminescence quantum yield and in the amplified spontaneous emission threshold. In parallel, hole field-effect mobility is significantly increased from 8.6 × 10(-7) to 3.8 × 10(-5) cm(2) V(-1) s(-1) upon thermal treatment, due to an increase of crystallinity. This study provides useful insights into the morphological control of oligofluorene thin films and how it affects their photophysical and charge transport properties. Moreover, we provide evidence that, because of the low threshold, the tunability of the amplified spontaneous emission and the photostability of the films, these oligofluorenes are promising candidates for organic solid-state laser applications.

14.
Opt Express ; 21(23): 28817-23, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24514394

RESUMO

We suggest optimally designed one-dimensional metal/photonic crystal structures for the excitation of optical Tamm plasmon polaritons, which show strongly enhanced electromagnetic field intensities compared to those due to conventional surface plasmon excitations. We assume that the photonic crystal is made of weakly nonlinear optical materials and calculate the reflectance and the electromagnetic field distribution precisely, using the invariant imbedding method generalized to nonlinear media. We find field intensity enhancement factors as large as 3,000 at the metal/photonic crystal interface. We verify that due to this strong enhancement, nonlinear optical effects such as optical bistability can be observed for very small values of the incident wave power. Our results imply that using our structure, very strong surface enhanced Raman scattering signals can be achieved and optical switching devices can be operated in much lower threshold light intensities.

15.
Opt Express ; 21(15): 17492-7, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23938619

RESUMO

Electric switching of reflection resonances at near-IR spectral range is experimentally demonstrated in a reflective metamaterial twisted nematic liquid crystal cell. Reflective metamaterial composed of nano-sized double-split ring resonator aperture is fabricated by a focused ion beam milling. Two-fold rotational symmetry of double-split ring resonators allows for two orthogonal polarization-dependent reflection resonances in the reflective metamaterial. With an external voltage of 10V across 12µm cell gap, a full switching is achieved between two reflection resonances. Dynamic measurements show the time constants of switch-on and switch-off are in the order of 100ms and 10ms, respectively.


Assuntos
Cristais Líquidos/química , Cristais Líquidos/efeitos da radiação , Nanotecnologia/instrumentação , Refratometria/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
16.
Nanotechnology ; 24(1): 015306, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23220863

RESUMO

By focused ion beam milling, we fabricated near-IR reflective metamaterials consisting of nano-aperture arrays. Optimum parameters of ion beam current and accelerating voltage in the fabrication process are obtained. Nano-apertures constituting reflective metamaterial are successfully milled, and possess a reflective resonance in the near-IR spectral range. With a double-split-ring resonator structure for the nano-aperture, the intensity reflection at resonance is rendered polarization dependent. It is found that the point group symmetry of the nano-aperture array determines the amount of anisotropy in the intensity reflection. Finite-difference time-domain simulation was adopted to identify details of nano-aperture metastructures transferred from nano-aperture patterns by the focused ion beam milling.

17.
Phys Chem Chem Phys ; 15(8): 2867-72, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23337941

RESUMO

We report on singlet-singlet annihilation and exciton diffusion in as-prepared p-type and annealed n-type thin films of the low-bandgap quinoidal quaterthiophene [QQT(CN)4] using ultrafast transient absorption measurements. The decay dynamics of exciton populations are well described by a one-dimensional diffusion-limited bimolecular recombination, indicating that the singlet excitons migrate preferentially along the stacking direction. Our results show that the exciton diffusion constants in QQT(CN)4 films do not vary significantly upon thermal annealing. Exciton diffusion lengths are measured to be as high as 4 and 5 nm in as-prepared and annealed QQT(CN)4 films, respectively. We also observe an influence of the excitation densities on the singlet exciton diffusion, which is attributed to phonon scattering. Because of the possibility of patterning p-n regions in QQT(CN)4 films by thermal nanolithography techniques, this study provides important insight not only into the photophysical properties of quinoidal oligothiophene derivatives but also for their future integration into high-performance p-n nanostructured near infrared light-sensing devices.

18.
Genet Mol Res ; 12(3): 3750-4, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24085436

RESUMO

Paulownia kawakamii is a fast-growing timber tree. In this study, 21 primer sets were developed using an enriched genomic library. The genetic diversity was measured in one P. kawakamii population. The number of alleles per locus ranged from 2 to 19. The observed and expected heterozygosities varied from 0.158 to 0.842 (mean = 0.421) and from 0.376 to 0.952 (mean = 0.771), respectively. All 21 loci were also polymorphic in closely related species (P. tomentosa, P. elongata, and P. fortunei). The described markers will be useful in future population genetic studies and molecular breeding of these Paulownia species.


Assuntos
Repetições de Microssatélites , Scrophulariaceae/classificação , Scrophulariaceae/genética , Alelos , Primers do DNA/genética , Loci Gênicos , Variação Genética , Biblioteca Genômica , Heterozigoto , Especificidade da Espécie
19.
Eur Rev Med Pharmacol Sci ; 27(1): 333-351, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36647882

RESUMO

Type 2 diabetes mellitus (T2DM) is a huge challenge for global public health systems. Currently, healthcare policies advocate the prevention of the onset and progression of T2DM by improving individual lifestyles. The increasing benefits of intermittent fasting (IF) as a dietary intervention have been elucidated. However, the beneficial effects of IF in T2DM remain inconclusive. We demonstrated the physiological mechanisms underlying the positive effects of IF in T2DM. IF could trigger metabolic transformation to improve systemic metabolism and induce tissue-specific metabolic adaptations through alterations in the gut microbiota, adipose tissue remodeling, correction of circadian rhythm disturbances, and increased autophagy in peripheral tissues. The efficacy and safety of IF regimens in clinical applications carry a risk of hypoglycemia and require monitoring of blood glucose and timely adjustment of medications. However, there is limited evidence of a positive effect of IF in weight loss and improvement of glycemic variables. Overall, IF serves as a promising therapeutic target for T2DM and needs to be established by a large randomized controlled trial.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemia , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Jejum Intermitente , Glicemia/metabolismo , Obesidade , Jejum
20.
Br J Cancer ; 106(11): 1891-8, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22568968

RESUMO

BACKGROUND: Despite many studies on diet and bladder cancer, there are areas that remain unexplored including meat mutagens, specific vegetable groups, and vitamins from diet. METHODS: We conducted a population-based case-control study of bladder cancer in Maine, New Hampshire, and Vermont. A total of 1171 cases were ascertained through hospital pathology records and cancer registries from 2001 to 2004. Overall, 1418 controls were identified from the Department of Motor Vehicles (<65 years) and Center for Medicaid and Medicare Services (65-79 years) and were frequency-matched to cases by state, sex, and age (within 5 years). Diet was assessed with a self-administered Diet History Questionnaire. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Processed meat intake was positively associated with bladder cancer (highest vs lowest quartile OR: 1.28; 95% CI: 1.00-1.65; P(trend)=0.035), with a stronger association for processed red meat (OR: 1.41; 95% CI: 1.08-1.84; P(trend)=0.024). There were no associations between intake of fruits or vegetables and bladder cancer. We did, however, observe an inverse association with vitamin B12 intake (OR: 0.77; 95% CI: 0.61-0.99; P=0.019). CONCLUSION: Vitamin B12 from diet may be protective against bladder cancer, whereas consuming processed meat may increase risk.


Assuntos
Dieta , Frutas , Carne/efeitos adversos , Micronutrientes , Neoplasias da Bexiga Urinária/epidemiologia , Verduras , Adulto , Idoso , Animais , Estudos de Casos e Controles , Dieta/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New England/epidemiologia , Fatores de Risco , Complexo Vitamínico B
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