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1.
Sci Rep ; 11(1): 14192, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262055

RESUMO

X-ray irradiation of high Z elements causes photoelectric effects that include the release of Auger electrons that can induce localized DNA breaks. We have previously established a tumor spheroid-based assay that used gadolinium containing mesoporous silica nanoparticles and synchrotron-generated monochromatic X-rays. In this work, we focused on iodine and synthesized iodine-containing porous organosilica (IPO) nanoparticles. IPO were loaded onto tumor spheroids and the spheroids were irradiated with 33.2 keV monochromatic X-ray. After incubation in CO2 incubator, destruction of tumor spheroids was observed which was accompanied by apoptosis induction, as determined by the TUNEL assay. By employing the γH2AX assay, we detected double strand DNA cleavages immediately after the irradiation. These results suggest that IPO first generate double strand DNA breaks upon X-ray irradiation followed by apoptosis induction of cancer cells. Use of three different monochromatic X-rays having energy levels of 33.0, 33.2 and 33.4 keV as well as X-rays with 0.1 keV energy intervals showed that the optimum effect of all three events (spheroid destruction, apoptosis induction and generation of double strand DNA breaks) occurred with a 33.2 keV monochromatic X-ray. These results uncover the preferential effect of K-edge energy X-ray for tumor spheroid destruction mediated by iodine containing nanoparticles.


Assuntos
Quebras de DNA/efeitos da radiação , Iodo/química , Nanopartículas/química , Neoplasias/patologia , Compostos Orgânicos/química , Dióxido de Silício/química , Esferoides Celulares/efeitos da radiação , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Humanos , Nanopartículas/ultraestrutura , Compostos Orgânicos/síntese química , Porosidade , Dióxido de Silício/síntese química , Raios X
2.
Med Dosim ; 46(1): 74-79, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32958360

RESUMO

To simulate an early 20th century viral pneumonia radiotherapy treatment using modern fluoroscopy and evaluated it according to current dose guidelines. Monte Carlo was used to assess the dose distribution on an anthropomorphic phantom. Critical organs were: skin, breasts, esophagus, ribs, vertebrae, heart, thymus, and spinal cord. A 100 kVp beam with 3 mm Al HVL, 25 × 25 cm2 posterior-anterior (PA) field and 50 cm source-to-surface distance were simulated. Simulations had a resolution of 0.4 × 0.4 × 0.06 cm3 and a 6% uncertainty. Hundred percent dose was normalized to the skin surface and results were displayed in axial, coronal, and sagittal planes. Dose volume histograms were generated in MATLAB for further analysis. Prescription doses of 0.3, 0.5, and 1.0 Gy were applied to the 15% isodose for organ-dose comparison to current tolerances and potential risk of detriment. Ninety-five and ninety-seven percent of the right and left lung volumes, respectively, were well-covered by the 15% isodose line. For the 0.3, 0.5, and 1.0 Gy prescriptions, the maximum skin doses were 2.9, 4.8, and 9.6 Gy compared to a 2.0 Gy transient erythema dose threshold; left/right lung maximum doses were 1.44/1.46, 2.4/2.4, and 4.8/4.9 Gy compared to a 6.5 Gy pneumonitis and 30 Gy fibrosis thresholds; maximum heart doses were 0.5, 0.9, and 1.8 Gy compared to the 0.5 Gy ICRP-recommendation; maximum spinal cord doses were 1.4, 2.3, and 4.6 Gy compared to 7.0 Gy single fraction dose threshold. Maximum doses to other critical organs were below modern dose thresholds. A 100 kVp PA field could deliver a 0.3 Gy or 0.5 Gy dose without risk of complications. However, a 1.0 Gy dose treatment could be problematic. Critical organ doses could be further reduced if more than one treatment field is used.


Assuntos
Pneumonia , Planejamento da Radioterapia Assistida por Computador , Fluoroscopia , Humanos , Método de Monte Carlo , Dosagem Radioterapêutica
4.
Sci Rep ; 9(1): 13275, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570738

RESUMO

Synchrotron generated monochromatic X-rays can be precisely tuned to the K-shell energy of high Z materials resulting in the release of the Auger electrons. In this work, we have employed this mechanism to destruct tumor spheroids. We first loaded gadolinium onto the surface of mesoporous silica nanoparticles (MSNs) producing gadolinium-loaded MSN (Gd-MSN). When Gd-MSN was added to the tumor spheroids, we observed efficient uptake and uniform distribution of Gd-MSN. Gd-MSN also can be taken up into cancer cells and localize to a site just outside of the cell nucleus. Exposure of the Gd-MSN containing tumor spheroids to monochromatic X-ray beams resulted in almost complete destruction. Importantly, this effect was observed at an energy level of 50.25 keV, but not with 50.0 keV. These results suggest that it is possible to use precisely tuned monochromatic X-rays to destruct tumor mass loaded with high Z materials, while sparing other cells. Our experiments point to the importance of nanoparticles to facilitate loading of gadolinium to tumor spheroids and to localize at a site close to the nucleus. Because the nanoparticles can target to tumor, our study opens up the possibility of developing a new type of radiation therapy for cancer.


Assuntos
Gadolínio , Nanopartículas Metálicas , Neoplasias Ovarianas , Linhagem Celular Tumoral , Feminino , Gadolínio/química , Gadolínio/farmacologia , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/radioterapia , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Terapia por Raios X
5.
Nature ; 561(7723): 318-319, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30232429
6.
Hum Mov Sci ; 58: 260-267, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29524851

RESUMO

Reducing external joint moments during gait can lead to a reduction in dynamic joint load. There has yet to be a detailed investigation of gait strategies that can reduce external joint moments by decreasing the magnitude of ground reaction force (GRF) without reducing the walking speed. The objectives of this study were to verify whether it is possible to reduce external joint moments by decreasing the GRF magnitude without reducing the walking speed and to identify the alternative walking strategy involved in young healthy adults. This study included 14 young healthy subjects. They performed two types of walking: normal and impact reduction walking. For impact reduction walking, the subjects walked in a manner that reduced the impact upon foot contact. Cadence and step length were unified between the two conditions. The walking speed, peak value of vertical GRF, braking-accelerating force, loading rate, joint angle, and external joint moments of the two conditions were recorded and compared. No significant difference was noted in the walking speed. However, the first peak of vertical GRF, braking force, and loading rate during loading response were significantly reduced during impact reduction walking, and external joint moments in the hip, knee, and ankle joints were reduced. In contrast, the second peak of vertical GRF, hip extension angle, and external ankle dorsiflexion moment were significantly increased during terminal stance. Our data imply that the ankle joint function during the terminal stance is important in reducing the dynamic joint load in the contralateral leg during the loading response.


Assuntos
Articulação do Tornozelo/fisiologia , Marcha/fisiologia , Articulação do Joelho/fisiologia , Extremidade Inferior/fisiologia , Caminhada/fisiologia , Adulto , Tornozelo/fisiologia , Fenômenos Biomecânicos , Feminino , Pé/fisiopatologia , Voluntários Saudáveis , Articulação do Quadril/fisiologia , Humanos , Joelho/fisiologia , Masculino , Movimento , Velocidade de Caminhada , Adulto Jovem
7.
Oncol Lett ; 13(1): 45-50, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28123520

RESUMO

Based on our previous analysis of neutral glycolipids in the human endometrium, the present authors already reported that the concentrations of glucosylceramide, lactosylceramide and globotriaosylceramide (Gb3Cer), in which both fatty acids and sphingosines in the ceramides are hydroxylated, exhibit a marked increase during the luteal phase of the menstrual cycle. It is also well known that poorly differentiated endometrial adenocarcinoma exhibits a more rapid progression and a worse response to therapy than well-differentiated endometrial adenocarcinoma. To examine the molecular background of well-differentiated and poorly differentiated cancers, the levels of neutral glycolipids in tumor tissues from endometrial carcinoma displaying different degrees of differentiation were measured. The composition of neutral glycolipids in tumor tissues was determined, and ceramide structures that were specifically expressed in well-differentiated endometrial carcinomas were investigated using biochemical analytical methods, including lipid extraction, enzyme digestion, thin-layer chromatography (TLC), gas-liquid chromatography and mass spectrometry. Well-differentiated adenocarcinoma contained numerous structurally unknown glycolipids that exhibited slower migration than globotetraosylceramide (Gb4Cer). In the case of Gb3Cer, three bands appeared on TLC in well-differentiated cancer, but only two bands appeared in the poorly-differentiated cancer. This difference was associated with the fatty acid composition of ceramide, since non-hydroxy fatty acids with ≥20 carbon atoms were increased in well-differentiated cancer, while α-hydroxy fatty acids were increased in poorly differentiated cancer. Similarly, there were two bands on TLC of Gb4Cer from well-differentiated cancer, but only one band in poorly differentiated cancer, and the long-chain base of ceramide was observed to contain phytosphingosine in well-differentiated cancer. It was demonstrated in endometrial cancer that the structure of ceramide molecules changes with the extent of tumor differentiation. These findings suggest that hydroxylated ceramides contribute to the well-differentiated phenotype of endometrial adenocarcinoma.

9.
Sci Rep ; 6: 30491, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27457890

RESUMO

The promising ability of a plasma wiggler based on laser wakefield acceleration to produce betatron X-rays with photon energies of a few keV to hundreds of keV and a peak brilliance of 10(22)-10(23) photons/s/mm(2)/mrad(2)/0.1%BW has been demonstrated, providing an alternative to large-scale synchrotron light sources. Most methods for generating betatron radiation are based on two typical approaches, one relying on an inherent transverse focusing electrostatic field, which induces transverse oscillation, and the other relying on the electron beam catching up with the rear part of the laser pulse, which results in strong electron resonance. Here, we present a new regime of betatron γ-ray radiation generated by stimulating a large-amplitude transverse oscillation of a continuously injected electron bunch through the hosing of the bubble induced by the carrier envelope phase (CEP) effect of the self-steepened laser pulse. Our method increases the critical photon energy to the MeV level, according to the results of particle-in-cell (PIC) simulations. The highly collimated, energetic and femtosecond γ-ray bursts that are produced in this way may provide an interesting potential means of exploring nuclear physics in table top photo nuclear reactions.

10.
Tokai J Exp Clin Med ; 41(1): 42-5, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-27050895

RESUMO

We report a case of vulvar aggressive angiomyxoma (AA) which is a rare, slow growing and benign tumor of mesenchymal origin, but has a high risk of local recurrence. A 49-year-old Japanese female was referred to us with a large mass of the left vulva, measuring 15×9.5×9 centimeters. She underwent surgical excision of the tumor with no evidence of recurrence on a 5-year follow up. In this case, histopathological examination and immunohistochemical staining after excision revealed a diagnosis of vulvar AA with estrogen and progesterone receptors positive. Aggressive angiomyxoma of the vulva needs to be distinguished from benign myxoid tumor with a low risk of local recurrence as well as from malignant neoplasma. The first line treatment of AA is complete surgical excision with tumor free margins, it will reduce the recurrence.


Assuntos
Angiomioma/patologia , Angiomioma/cirurgia , Neoplasias Vulvares/patologia , Neoplasias Vulvares/cirurgia , Angiomioma/diagnóstico , Angiomioma/metabolismo , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Risco , Fatores de Tempo , Neoplasias Vulvares/diagnóstico , Neoplasias Vulvares/metabolismo
11.
Science ; 331(6013): 41-2, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21212346
12.
Radiol Phys Technol ; 3(1): 16-22, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20821097

RESUMO

The results of Monte Carlo calculated dose distributions of proton treatment of ocular melanoma are presented. An efficient spot scanning method utilizing active energy modulation, which also minimizes the number of target spots was developed. We simulated various parameter values for the particle energy spread and the pencil beam diameter in order to determine values suitable for medical treatment. We found that a 2.5-mm-diameter proton beam with a 5% Gaussian energy spread was suitable for treatment of ocular melanoma while preserving vision for the typical case that we simulated. The energy spectra and the required proton current were also calculated and are reported. The results are intended to serve as a guideline for a new class of low-cost, compact accelerators.


Assuntos
Neoplasias Oculares/radioterapia , Melanoma/radioterapia , Terapia com Prótons , Doses de Radiação , Neoplasias Oculares/patologia , Humanos , Lasers , Melanoma/patologia , Método de Monte Carlo , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Carga Tumoral
13.
Appl Opt ; 49(11): 2105-15, 2010 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-20390013

RESUMO

We have developed a femtosecond high-intensity laser system that combines both Ti:sapphire chirped-pulse amplification (CPA) and optical parametric CPA (OPCPA) techniques and produces more than 30 J broadband output energy, indicating the potential for achieving peak powers in excess of 500 TW. With a cleaned high-energy seeded OPCPA preamplifier as a front end in the system, for the compressed pulse without pumping the final amplifier, we found that the temporal contrast in this system exceeds 10(10) on the subnanosecond time scales, and is near 10(12) on the nanosecond time scale prior to the peak of the main femtosecond pulse. Using diffractive optical elements for beam homogenization of a 100 J level high-energy Nd:glass green pump laser in a Ti:sapphire final amplifier, we have successfully generated broadband high-energy output with a near-perfect top-hat-like intensity distribution.


Assuntos
Lasers , Óptica e Fotônica , Óxido de Alumínio/química , Amplificadores Eletrônicos , Desenho de Equipamento , Risco , Processamento de Sinais Assistido por Computador/instrumentação , Fatores de Tempo , Titânio/química
14.
Artigo em Inglês | MEDLINE | ID: mdl-20228616

RESUMO

Laser acceleration is based on the concept to marshal collective fields that may be induced by laser. In order to exceed the material breakdown field by a large factor, we employ the broken-down matter of plasma. While the generated wakefields resemble with the fields in conventional accelerators in their structure (at least qualitatively), it is their extreme accelerating fields that distinguish the laser wakefield from others, amounting to tiny emittance and compact accelerator. The current research largely falls on how to master the control of acceleration process in spatial and temporal scales several orders of magnitude smaller than the conventional method. The efforts over the last several years have come to a fruition of generating good beam properties with GeV energies on a table top, leading to many applications, such as ultrafast radiolysis, intraoperative radiation therapy, injection to X-ray free electron laser, and a candidate for future high energy accelerators.


Assuntos
Lasers , Aceleradores de Partículas
15.
Fertil Steril ; 94(1): 305-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19269632

RESUMO

OBJECTIVE: To show soluble fms-like tyrosine kinase 1 (sFlt1) levels in sera from patients with hydatidiform mole, which is known to predispose women to severe early-onset preeclampsia. DESIGN: Comparative study. SETTING: University hospital and surrounding community hospitals. PATIENT(S): Seven women with pathologically diagnosed complete hydatidiform mole (mole group), 21 gestational- and maternal-age-matched women who did not develop any pregnant complication during their pregnancy (control group), and eight women who subsequently developed preeclampsia (preclinical preeclampsia group). INTERVENTION(S): Blood samples were taken before and after evacuations of hydatidiform mole. MAIN OUTCOME MEASURE(S): Concentrations of sFlt1 and free placental growth factor (PlGF) in serum were measured by ELISA. RESULT(S): Serum sFlt1 concentrations were significantly higher in the mole group compared with the control group and the preclinical preeclampsia group. In contrast, serum free PlGF concentrations were significantly lower in the mole group. In the mole group, there was a significant negative correlation between sFlt1 and PlGF serum concentrations. After the evacuation of hydatidiform mole, the level of serum sFlt1 decreased dramatically. CONCLUSION(S): Elevated levels of sFlt1 were noted in molar gestations and may play in a role in early-onset preeclampsia reported in such pregnancies.


Assuntos
Mola Hidatiforme/diagnóstico , Mola Hidatiforme/enzimologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Mola Hidatiforme/sangue , Gravidez , Solubilidade , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Adulto Jovem
16.
Hum Reprod ; 24(2): 408-14, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18978361

RESUMO

BACKGROUND: The increase in concentration of osteoprotegerin, an antagonist of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), in the peritoneal fluid of women with endometriosis may interfere with TRAIL-induced apoptosis in endometriotic cells and promote the development of endometriosis. In the present study, the effect of tunicamycin, a possible apoptosis enhancer, on TRAIL-induced apoptosis in endometriotic stromal cells (ESC) was determined. METHODS: ESC were isolated from cyst walls of ovarian endometrioma and cultured. ESC were incubated with or without tunicamycin (2 microg/ml) for the first 16 h, and then incubated with or without TRAIL (200 ng/ml) for the following 24 h. To examine whether caspases were involved in TRAIL-induced apoptosis, z-VAD-fmk (30 microM), a general caspase inhibitor, was added 1 h before TRAIL treatment. ESC were transfected with small interfering RNA (siRNA) for DR5, a receptor of TRAIL, before tunicamycin treatment to evaluate its role in ESC. DR5 mRNA level was determined by quantitative RT-PCR. Apoptosis in ESC was evaluated by flow cytometry. RESULTS: Tunicamycin increases both DR5 mRNA (P < 0.005) and TRAIL-induced apoptosis (P < 0.0001) in ESC. The increase in TRAIL-induced apoptosis in ESC by tunicamycin was suppressed (P < 0.05) by z-VAD-fmk. Transfection with DR5 siRNA suppressed the tunicamycin-induced increase in DR5 mRNA and abrogated the up-regulation of TRAIL-induced apoptosis by tunicamycin. CONCLUSIONS: The combined treatment with tunicamycin and TRAIL may have therapeutic potential in the treatment of endometriosis.


Assuntos
Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Endometriose/patologia , Células Estromais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Tunicamicina/farmacologia , Células Cultivadas , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Interferência de RNA , RNA Mensageiro/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Células Estromais/patologia
17.
Endocrinology ; 150(1): 350-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18787030

RESUMO

IL-1, secreted by human embryos and trophoblast cells, is important for successful implantation and pregnancy. We previously reported that IL-1beta induced IL-8 production in human endometrial stromal cells (ESCs) and that induction was regulated by substances implicated in implantation. In the present study using human primary cells in culture, we measured IL-1beta-induced production of IL-8 from endometrial epithelial cells (EECs) and ESCs and examined effects of the endometrium-derived IL-8 on migration and number of first-trimester villous cytotrophoblast cells (vCTs). Both basal and IL-1beta-induced IL-8 levels of cell supernatants were much higher in EECs than ESCs. Addition of IL-1beta to EECs increased the chemotactic activity of the supernatants to vCTs, and this effect was suppressed by immunoneutralization with anti-IL-8 antibody. Supernatants of IL-1beta-stimulated EECs yielded significantly higher number of vCTs compared with those of untreated EECs, and the effect was inhibited by IL-8 antibody. These findings suggest that IL-1 promotes implantation by stimulating EECs to produce IL-8, which subsequently induces migration of vCTs and contributes to survival of vCTs.


Assuntos
Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Endométrio/fisiologia , Células Epiteliais/fisiologia , Interleucina-1beta/farmacologia , Interleucina-9/fisiologia , Primeiro Trimestre da Gravidez , Adulto , Técnicas de Cultura de Células , Endométrio/citologia , Endométrio/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Interleucina-8/farmacologia , Pessoa de Meia-Idade , Gravidez
18.
Chem Commun (Camb) ; (41): 5167-9, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18956057

RESUMO

On the basis of the concept of site isolation in electrochemical reactions, we have successfully demonstrated acceleration of the deprotonation step in anodic methoxylation of fluoroethyl phenyl sulfides using silica gel supported bases.

19.
Am J Pathol ; 173(2): 463-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18599603

RESUMO

Several lines of evidence indicate that the Th2 immune response is associated with endometriosis. Although an increased concentration of interleukin (IL)-4, a typical Th2 cytokine, has been reported in endometriotic tissues, the implication of this for endometriosis has not been determined. To investigate a possible role of IL-4 in the development of endometriosis, we examined the presence of IL-4-producing cells in endometriotic tissues and the effect of IL-4 on proliferation of endometriotic stromal cells. Endometriotic stromal cells were isolated from endometriotic tissues obtained from women undergoing surgery for endometrioma. Immunohistochemistry of endometriotic tissues revealed that IL-4-positive cells were abundant in the stroma. The effect of IL-4 on proliferation of endometriotic stromal cells was studied using cell counting and BrdU incorporation assays. IL-4 (0.1 to 10 ng/ml) significantly increased cell number and BrdU incorporation in a dose-dependent manner, and the proliferative effect of IL-4 was inhibited by anti-IL-4 receptor antibody. IL-4-induced activation of mitogen-activated protein kinases in endometriotic stromal cells was examined by Western blotting. IL-4 induced phosphorylation of p38 mitogen-activated protein kinase, stress-activated protein kinase/c-Jun kinase, and p42/44 mitogen-activated protein kinase and inhibitors of these kinases suppressed IL-4-induced proliferation of endometriotic stromal cells. These findings suggest that proliferation of endometriotic stromal cells induced by locally produced IL-4 is involved in the development of endometriosis.


Assuntos
Proliferação de Células , Endometriose/metabolismo , Endométrio/patologia , Interleucina-4/fisiologia , Adulto , Bromodesoxiuridina , Endometriose/patologia , Feminino , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Receptores de Interleucina-4/metabolismo , Células Estromais/fisiologia
20.
J Org Chem ; 73(17): 6888-90, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18652509

RESUMO

We have developed a novel electrolytic system for Kolbe carbon-carbon coupling electrosynthesis based on the acid-base reaction between carboxylic acids as a substrate and solid-supported bases. On the basis of the electrolytic system, Kolbe electrolysis of various carboxylic acids was successfully carried out to provide the corresponding homocoupling products in moderate to excellent yields.

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