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1.
Psychiatry Res ; 284: 112601, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31883740

RESUMO

There is a mortality gap of 15 to 20 years for people with severe mental illness (SMI - psychotic spectrum, bipolar, major depressive disorders). Modifiable risk factors include inactivity and low cardiorespiratory fitness (CRF). Exercise can improve mental and physical outcomes; optimal type and intensity of exercise for people with SMI has yet to be determined. High Intensity Interval training (HIIT) is an exercise with distinct cardio-metabolic advantages in other disease populations compared to traditional moderate intensity continuous training (MCT). We investigated the feasibility and efficacy of HIIT for people with SMI. Major electronic databases were searched, identifying HIIT studies for adults experiencing SMI.Data on feasibility, safety, study design, sample characteristics, and physical and psychological outcomes were extracted and systematically reviewed. Meta-analyses were conducted within group, pre and post HIIT interventions, and between group, to compare HIIT with control conditions. Nine articles were identified including three pre/post studies, one non randomised and five randomised trials, (366 participants, 45.1% female). HIIT appears as feasible as MCT, with few safety concerns. Following HIIT, there was a moderate improvement in CRF and depression. There was no difference between HIIT and MCT for adherence or CRF.HIIT improved depression more than MCT.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Treinamento Intervalado de Alta Intensidade/psicologia , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Recuperação de Função Fisiológica/fisiologia , Adulto , Aptidão Cardiorrespiratória/fisiologia , Aptidão Cardiorrespiratória/psicologia , Exercício Físico/fisiologia , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Transtornos Mentais/fisiopatologia , Pessoa de Meia-Idade , Exame Físico/métodos , Exame Físico/psicologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-27242909

RESUMO

Background. Primary dysmenorrhea is a common gynaecological condition. Traditional Chinese medicine (TCM) acupuncturists commonly treat primary dysmenorrhea and dispense specific self-care advice for this condition. The impact of self-care advice on primary dysmenorrhea is unknown. Methods. 19 TCM acupuncture practitioners from New Zealand or Australia and 12 New Zealand women who had recently undergone acupuncture treatment for primary dysmenorrhea as part of a randomised controlled trial participated in this qualitative, pragmatic study. Focus groups and semistructured interviews were used to collect data. These were recorded, transcribed, and analysed using thematic analysis. Results. The overarching theme was that an acupuncture treatment consisted of "more than needles" for both practitioners and participants. Practitioners and participants both discussed the partnership they engaged in during treatment, based on openness and trust. Women felt that the TCM self-care advice was related to positive outcomes for their dysmenorrhea and increased their feelings of control over their menstrual symptoms. Conclusions. Most of the women in this study found improved symptom control and reduced pain. A contributing factor for these improvements may be an increased internal health locus of control and an increase in self-efficacy resulting from the self-care advice given during the clinical trial.

4.
J Neurooncol ; 128(2): 225-33, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27021492

RESUMO

Stem cell therapies are being developed for radiotherapy-induced brain injuries (RIBI). Magnetic resonance imaging (MRI) offers advantages for imaging transplanted stem cells. However, most MRI cell-tracking techniques employ superparamagnetic iron oxide particles (SPIOs), which are difficult to distinguish from hemorrhage. In current preclinical RIBI models, hemorrhage occurs concurrently with other injury markers. This makes the evaluation of the recruitment of transplanted SPIO-labeled stem cells to injury sites difficult. Here, we developed a RIBI model, with early injury markers reflective of hippocampal dysfunction, which can be detected noninvasively with MRI and behavioral tests. Lesions were generated by sub-hemispheric irradiation of mouse hippocampi with single X-ray beams of 80 Gy. Lesion formation was monitored with anatomical and contrast-enhanced MRI and changes in memory and learning were assessed with fear-conditioning tests. Early injury markers were detected 2 weeks after irradiation. These included an increase in the permeability of the blood-brain barrier, demonstrated by a 92 ± 20 % contrast enhancement of the irradiated versus the non-irradiated brain hemispheres, within 15 min of the administration of an MRI contrast agent. A change in short-term memory was also detected, as demonstrated by a 40.88 ± 5.03 % decrease in the freezing time measured during the short-term memory context test at this time point, compared to that before irradiation. SPIO-labeled stem cells transplanted contralateral to the lesion migrated toward the lesion at this time point. No hemorrhage was detected up to 10 weeks after irradiation. This model can be used to evaluate SPIO-based stem cell-tracking agents, short-term.


Assuntos
Escala de Avaliação Comportamental , Aprendizagem , Imageamento por Ressonância Magnética , Memória , Lesões Experimentais por Radiação/diagnóstico por imagem , Lesões Experimentais por Radiação/psicologia , Animais , Hipocampo/diagnóstico por imagem , Hipocampo/lesões , Hipocampo/efeitos da radiação , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/psicologia , Masculino , Camundongos Endogâmicos BALB C , Lesões Experimentais por Radiação/terapia , Transplante de Células-Tronco , Células-Tronco , Raios X
5.
Sci Rep ; 5: 13628, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26330231

RESUMO

Stem cell therapies are currently being investigated for the repair of brain injuries. Although exogenous stem cell labelling with superparamagnetic iron oxide nanoparticles (SPIONs) prior to transplantation provides a means to noninvasively monitor stem cell transplantation by magnetic resonance imaging (MRI), monitoring cell death is still a challenge. Here, we investigate the feasibility of using an MRI dual-contrast technique to detect cell delivery, cell migration and cell death after stem cell transplantation. Human mesenchymal stem cells were dual labelled with SPIONs and gadolinium-based chelates (GdDTPA). The viability, proliferation rate, and differentiation potential of the labelled cells were then evaluated. The feasibility of this MRI technique to distinguish between live and dead cells was next evaluated using MRI phantoms, and in vivo using both immune-competent and immune-deficient mice, following the induction of brain injury in the mice. All results were validated with bioluminescence imaging. In live cells, a negative (T2/T2*) MRI contrast predominates, and is used to track cell delivery and cell migration. Upon cell death, a diffused positive (T1) MRI contrast is generated in the vicinity of the dead cells, and serves as an imaging marker for cell death. Ultimately, this technique could be used to manage stem cell therapies.


Assuntos
Meios de Contraste/química , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Animais , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/patologia , Morte Celular , Movimento Celular , Rastreamento de Células , Gadolínio DTPA , Humanos , Ferro/metabolismo , Medições Luminescentes , Fenômenos Magnéticos , Camundongos Endogâmicos BALB C , Camundongos SCID , Imagens de Fantasmas , Lesões por Radiação/diagnóstico , Lesões por Radiação/patologia , Coloração e Rotulagem
6.
Phys Med Biol ; 60(13): 5163-77, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26083659

RESUMO

The conventional imaging geometry for small animal cone beam computed tomography (CBCT) is that a detector panel rotates around the head-to-tail axis of an imaged animal ('tubular' geometry). Another unusual but possible imaging geometry is that the detector panel rotates around the anterior-to-posterior axis of the animal ('pancake' geometry). The small animal radiation research platform developed at Johns Hopkins University employs the pancake geometry where a prone-positioned animal is rotated horizontally between an x-ray source and detector panel. This study is to assess the CBCT image quality in the pancake geometry and investigate potential methods for improvement. We compared CBCT images acquired in the pancake geometry with those acquired in the tubular geometry when the phantom/animal was placed upright simulating the conventional CBCT geometry. Results showed signal-to-noise and contrast-to-noise ratios in the pancake geometry were reduced in comparison to the tubular geometry at the same dose level. But the overall spatial resolution within the transverse plane of the imaged cylinder/animal was better in the pancake geometry. A modest exposure increase to two folds in the pancake geometry can improve image quality to a level close to the tubular geometry. Image quality can also be improved by inclining the animal, which reduces streak artifacts caused by bony structures. The major factor resulting in the inferior image quality in the pancake geometry is the elevated beam attenuation along the long axis of the phantom/animal and consequently increased scatter-to-primary ratio in that orientation. Not withstanding, the image quality in the pancake-geometry CBCT is adequate to support image guided animal positioning, while providing unique advantages of non-coplanar and multiple mice irradiation. This study also provides useful knowledge about the image quality in the two very different imaging geometries, i.e. pancake and tubular geometry, respectively.


Assuntos
Encéfalo/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/instrumentação , Tomografia Computadorizada de Feixe Cônico/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Razão Sinal-Ruído , Algoritmos , Animais , Camundongos , Método de Monte Carlo , Radiografia Torácica , Espalhamento de Radiação , Raios X
7.
Int J Hyperthermia ; 31(4): 359-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25811736

RESUMO

PURPOSE: We aimed to characterise magnetic nanoparticle hyperthermia (mNPH) with radiation therapy (RT) for prostate cancer. METHODS: Human prostate cancer subcutaneous tumours, PC3 and LAPC-4, were grown in nude male mice. When tumours measured 150 mm3 magnetic iron oxide nanoparticles (MIONPs) were injected into tumours to a target dose of 5.5 mg Fe/cm3 tumour, and treated 24 h later by exposure to alternating magnetic field (AMF). Mice were randomly assigned to one of four cohorts to characterise (1) intratumour MIONP distribution, (2) effects of variable thermal dose mNPH (fixed AMF peak amplitude 24 kA/m at 160 ± 5 kHz) with/without RT (5 Gy), (3) effects of RT (RT5: 5 Gy; RT8: 8 Gy), and (4) fixed thermal dose mNPH (43 °C for 20 min) with/without RT (5 Gy). MIONP concentration and distribution were assessed following sacrifice and tissue harvest using inductively coupled plasma mass spectrometry (ICP-MS) and Prussian blue staining, respectively. Tumour growth was monitored and compared among treated groups. RESULTS: LAPC-4 tumours retained higher MIONP concentration and more uniform distribution than did PC3 tumours. AMF power modulation provided similar thermal dose for mNPH and combination therapy groups (CEM43: LAPC-4: 33.6 ± 3.4 versus 25.9 ± 0.8, and PC3: 27.19 ± 0.7 versus 27.50 ± 0.6), thereby overcoming limitations of MIONP distribution and yielding statistically significant tumour growth delay. CONCLUSION: PC3 and LAPC-4 tumours represent two biological models that demonstrate different patterns of nanoparticle retention and distribution, offering a model to make comparisons of these effects for mNPH. Modulating power for mNPH offers potential to overcome limitations of MIONP distribution to enhance mNPH.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas de Magnetita/administração & dosagem , Neoplasias da Próstata/terapia , Radiossensibilizantes/farmacologia , Animais , Linhagem Celular Tumoral , Terapia Combinada , Humanos , Magnetoterapia , Nanopartículas de Magnetita/uso terapêutico , Masculino , Espectrometria de Massas , Camundongos , Neoplasias da Próstata/radioterapia
8.
Complement Ther Med ; 22(4): 710-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25146076

RESUMO

BACKGROUND: Acupuncture is used by nine percent of the Australian population; however, we know relatively little about the practice of acupuncture to treat women's reproductive health in Australia and New Zealand. METHODS: This study surveyed acupuncturists to examine their practice with treating women's reproductive health complaints. A cross sectional survey of 3406 Australian and New Zealand acupuncturists was conducted. A self-completion questionnaire explored the areas of acupuncture treatment for gynaecological pregnancy and fertility complaints. RESULTS: Questionnaires were completed by 377 acupuncturists. Ninety-six percent of practitioners reported treating women's reproductive health conditions within the previous year. All three areas of women's reproductive health were commonly treated with 96% treating gynaecological health, 91% treating pregnancy conditions, and 90% fertility conditions. The most commonly treated gynaecological conditions were premenstrual syndrome (90.1%, 95% CI 86.2-93.0), menopause (89.4%, 95% CI 85.4-92.4) and primary dysmenorrhea (89.1%, 95% CI 85.1-92.2). Participants reported treating general fertility not related to assisted reproduction (93%, 95% CI 89.4-95.5), treatment for a diagnosed fertility related conditions (85.8%, 95% CI 81.1-89.4), and to decrease infertility related stress (86%, 95% CI 81.5-89.7). The most common pregnancy related conditions treated were nausea (90.3%, 95% CI 86.3-93.3), back or pelvic pain (89.3%, 95% CI 85.1-92.4), and prebirth labour preparation (86.8%, 95% CI 82.3-90.3). CONCLUSION: Treating women's reproductive health complaints was commonly reported among the groups of acupuncturists in Australia and New Zealand responding to this survey; however, our findings cannot be generalised to the wider acupuncture communities in these two countries.


Assuntos
Terapia por Acupuntura/métodos , Terapia por Acupuntura/estatística & dados numéricos , Pessoal de Saúde/estatística & dados numéricos , Distúrbios Menstruais/terapia , Serviços de Saúde da Mulher/estatística & dados numéricos , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Menopausa , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Adulto Jovem
9.
Transl Oncol ; 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24836647

RESUMO

OBJECTIVES: To determine whether poly (ADP-ribose) polymerase-1/2 (PARP-1/2) inhibition enhances radiation-induced cytotoxicity of pancreatic adenocarcinoma in vitro and in vivo, and the mechanism by which this occurs. METHODS: Pancreatic carcinoma cells were treated with ABT-888, radiation, or both. In vitro cell viability, apoptosis, and PARP activity were measured. Orthotopic xenografts were generated in athymic mice and treated with ABT-888 (25mg/kg), radiation (5Gy), both, or no treatment. Mice were monitored with bioluminescence imaging. RESULTS: In vitro, treatment with ABT-888 and radiation led to higher rates of cell death after 8days (P < .01). Co-treatment with 5Gy and 1, 10 or 100µmol/l of ABT-888 led to dose enhancement factors of 1.29, 1.41 and 2.36, respectively. Caspase activity was not significantly increased when treated with ABT-888 (10 µmol/l) alone (1.28-fold, P = .08), but became significant when radiation was added (2.03-fold, P < .01). PARP activity increased post-radiation and was abrogated following co-treatment with ABT-888. In vivo, treatment with ABT-888, radiation or both led to tumor growth inhibition (TGI) of 8, 30 and 39days, and survival at 60days of 0%, 0% and 40%, respectively. CONCLUSIONS: ABT-888 with radiation significantly enhanced tumor response in vitro and in vivo. ABT-888 inhibited PAR protein polymerization resulting in dose-dependent feedback up-regulation of PARP and p-ATM suggesting increased DNA damage. This translated into enhancement in TGI and survival with radiation in vivo. In vitro PAR levels correlated with levels of tumor apoptosis suggesting potential as a predictive biomarker. These data are being used to support a Phase I study in locally advanced pancreatic cancer.

10.
Radiat Res ; 179(4): 416-21, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23578189

RESUMO

In this study, we investigated the accuracy of using off-line bioluminescence imaging (BLI) and tomography (BLT) to guide irradiation of small soft tissue targets on a small animal radiation research platform (SARRP) with on-board cone beam CT (CBCT) capability. A small glass bulb containing BL cells was implanted as a BL source in the abdomen of 11 mouse carcasses. Bioluminescence imaging and tomography were acquired for each carcass. Six carcasses were setup visually without immobilization and 5 were restrained in position with tape. All carcasses were setup in treatment position on the SARRP where the centroid position of the bulb on CBCT was taken as "truth". In the 2D visual setup, the carcass was setup by aligning the point of brightest luminescence with the vertical beam axis. In the CBCT assisted setup, the pose of the carcass on CBCT was aligned with that on the 2D BL image for setup. For both 2D setup methods, the offset of the bulb centroid on CBCT from the vertical beam axis was measured. In the BLT-CBCT fusion method, the 3D torso on BLT and CBCT was registered and the 3D offset of the respective source centroids was calculated. The setup results were independent of the carcass being immobilized or not due to the onset of rigor mortis. The 2D offset of the perceived BL source position from the CBCT bulb position was 2.3 mm ± 1.3 mm. The 3D offset between BLT and CBCT was 1.5 mm ± 0.9 mm. Given the rigidity of the carcasses, the setup results represent the best that can be achieved with off-line 2D BLI and 3D BLT. The setup uncertainty would require the use of undesirably large margin of 4-5 mm. The results compel the implementation of on-board BLT capability on the SARRP to eliminate setup error and to improve BLT accuracy.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Medições Luminescentes/métodos , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Nus
11.
Radiat Res ; 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23432050

RESUMO

In this study, we investigated the accuracy of using off-line bioluminescence imaging (BLI) and tomography (BLT) to guide irradiation of small soft tissue targets on a small animal radiation research platform (SARRP) with on-board cone beam CT (CBCT) capability. A small glass bulb containing BL cells was implanted as a BL source in the abdomen of 11 mouse carcasses. Bioluminescence imaging and tomography were acquired for each carcass. Six carcasses were setup visually without immobilization and 5 were restrained in position with tape. All carcasses were setup in treatment position on the SARRP where the centroid position of the bulb on CBCT was taken as "truth". In the 2D visual setup, the carcass was setup by aligning the point of brightest luminescence with the vertical beam axis. In the CBCT assisted setup, the pose of the carcass on CBCT was aligned with that on the 2D BL image for setup. For both 2D setup methods, the offset of the bulb centroid on CBCT from the vertical beam axis was measured. In the BLT-CBCT fusion method, the 3D torso on BLT and CBCT was registered and the 3D offset of the respective source centroids was calculated. The setup results were independent of the carcass being immobilized or not due to the onset of rigor mortis. The 2D offset of the perceived BL source position from the CBCT bulb position was 2.3 mm ± 1.3 mm. The 3D offset between BLT and CBCT was 1.5 mm ± 0.9 mm. Given the rigidity of the carcasses, the setup results represent the best that can be achieved with off-line 2D BLI and 3D BLT. The setup uncertainty would require the use of undesirably large margin of 4-5 mm. The results compel the implementation of on-board BLT capability on the SARRP to eliminate setup error and to improve BLT accuracy.

12.
Int J Hyperthermia ; 29(2): 106-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23402327

RESUMO

PURPOSE: Solenoid coils that generate time-varying or alternating magnetic fields (AMFs) are used in biomedical devices for research, imaging and therapy. Interactions of AMF and tissue produce eddy currents that deposit power within tissue, thus limiting effectiveness and safety. We aim to develop methods that minimise excess heating of mice exposed to AMFs for cancer therapy experiments. MATERIALS AND METHODS: Numerical and experimental data were obtained to characterise thermal management properties of water using a continuous, custom water jacket in a four-turn simple solenoid. Theoretical data were obtained with method-of-moments (MoM) numerical field calculations and finite element method (FEM) thermal simulations. Experimental data were obtained from gel phantoms and mice exposed to AMFs having amplitude >50 kA/m and frequency of 160 kHz. RESULTS: Water has a high specific heat and thermal conductivity, is diamagnetic, polar, and nearly transparent to magnetic fields. We report at least a two-fold reduction of temperature increase from gel phantom and animal models when a continuous layer of circulating water was placed between the sample and solenoid, compared with no water. Thermal simulations indicate the superior efficiency in thermal management by the developed continuous single chamber cooling system over a double chamber non-continuous system. Further reductions of heating were obtained by regulating water temperature and flow for active cooling. CONCLUSIONS: These results demonstrate the potential value of a contiguous layer of circulating water to permit sustained exposure to high intensity alternating magnetic fields at this frequency for research using small animal models exposed to AMFs.


Assuntos
Temperatura Baixa , Campos Magnéticos , Animais , Regulação da Temperatura Corporal , Simulação por Computador , Desenho de Equipamento , Calefação/efeitos adversos , Hipertermia Induzida/instrumentação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Imagens de Fantasmas , Condutividade Térmica , Água
13.
Int J Radiat Oncol Biol Phys ; 86(1): 143-9, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23182391

RESUMO

PURPOSE: Despite improvements in chemoradiation, local control remains a major clinical problem in locally advanced non-small cell lung cancer. The Hedgehog pathway has been implicated in tumor recurrence by promoting survival of tumorigenic precursors and through effects on tumor-associated stroma. Whether Hedgehog inhibition can affect radiation efficacy in vivo has not been reported. METHODS AND MATERIALS: We evaluated the effects of a targeted Hedgehog inhibitor (HhAntag) and radiation on clonogenic survival of human non-small cell lung cancer lines in vitro. Using an A549 cell line xenograft model, we examined tumor growth, proliferation, apoptosis, and gene expression changes after concomitant HhAntag and radiation. In a transgenic mouse model of Kras(G12D)-induced and Twist1-induced lung adenocarcinoma, we assessed tumor response to radiation and HhAntag by serial micro-computed tomography (CT) scanning. RESULTS: In 4 human lung cancer lines in vitro, HhAntag showed little or no effect on radiosensitivity. By contrast, in both the human tumor xenograft and murine inducible transgenic models, HhAntag enhanced radiation efficacy and delayed tumor growth. By use of the human xenograft model to differentiate tumor and stromal effects, mouse stromal cells, but not human tumor cells, showed significant and consistent downregulation of Hedgehog pathway gene expression. This was associated with increased tumor cell apoptosis. CONCLUSIONS: Targeted Hedgehog pathway inhibition can increase in vivo radiation efficacy in lung cancer preclinical models. This effect is associated with pathway suppression in tumor-associated stroma. These data support clinical testing of Hedgehog inhibitors as a component of multimodality therapy for locally advanced non-small cell lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Proteínas Hedgehog/antagonistas & inibidores , Neoplasias Pulmonares/radioterapia , Proteínas de Neoplasias/antagonistas & inibidores , Tolerância a Radiação/fisiologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Anilidas/farmacologia , Animais , Apoptose , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Feminino , Proteínas Hedgehog/metabolismo , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Camundongos Transgênicos , Proteínas de Neoplasias/metabolismo , Piridinas/farmacologia , Transplante Heterólogo
14.
Transl Oncol ; 5(2): 77-84, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22496923

RESUMO

PURPOSE: We report on a novel preclinical pancreatic cancer research model that uses bioluminescence imaging (BLI)-guided irradiation of orthotopic xenograft tumors, sparing of surrounding normal tissues, and quantitative, noninvasive longitudinal assessment of treatment response. MATERIALS AND METHODS: Luciferase-expressing MiaPaCa-2 pancreatic carcinoma cells were orthotopically injected in nude mice. BLI was compared to pathologic tumor volume, and photon emission was assessed over time. BLI was correlated to positron emission tomography (PET)/computed tomography (CT) to estimate tumor dimensions. BLI and cone-beam CT (CBCT) were used to compare tumor centroid location and estimate setup error. BLI and CBCT fusion was performed to guide irradiation of tumors using the small animal radiation research platform (SARRP). DNA damage was assessed by γ-H2Ax staining. BLI was used to longitudinally monitor treatment response. RESULTS: Bioluminescence predicted tumor volume (R = 0.8984) and increased linearly as a function of time up to a 10-fold increase in tumor burden. BLI correlated with PET/CT and necropsy specimen in size (P < .05). Two-dimensional BLI centroid accuracy was 3.5 mm relative to CBCT. BLI-guided irradiated pancreatic tumors stained positively for γ-H2Ax, whereas surrounding normal tissues were spared. Longitudinal assessment of irradiated tumors with BLI revealed significant tumor growth delay of 20 days relative to controls. CONCLUSIONS: We have successfully applied the SARRP to a bioluminescent, orthotopic preclinical pancreas cancer model to noninvasively: 1) allow the identification of tumor burden before therapy, 2) facilitate image-guided focal radiation therapy, and 3) allow normalization of tumor burden and longitudinal assessment of treatment response.

15.
Int J Radiat Oncol Biol Phys ; 83(3): e431-6, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22483739

RESUMO

PURPOSE: Radiation necrosis is a major complication of radiation therapy. We explore the features of radiation-induced brain necrosis in the rat, using multiple MRI approaches, including T(1), T(2), apparent diffusion constant (ADC), cerebral blood flow (CBF), magnetization transfer ratio (MTR), and amide proton transfer (APT) of endogenous mobile proteins and peptides. METHODS AND MATERIALS: Adult rats (Fischer 344; n = 15) were irradiated with a single, well-collimated X-ray beam (40 Gy; 10 × 10 mm(2)) in the left brain hemisphere. MRI was acquired on a 4.7-T animal scanner at ~25 weeks' postradiation. The MRI signals of necrotic cores and perinecrotic regions were assessed with a one-way analysis of variance. Histological evaluation was accomplished with hematoxylin and eosin staining. RESULTS: ADC and CBF MRI could separate perinecrotic and contralateral normal brain tissue (p < 0.01 and < 0.05, respectively), whereas T(1), T(2), MTR, and APT could not. MRI signal intensities were significantly lower in the necrotic core than in normal brain for CBF (p < 0.001) and APT (p < 0.01) and insignificantly higher or lower for T(1), T(2), MTR, and ADC. Histological results demonstrated coagulative necrosis within the necrotic core and reactive astrogliosis and vascular damage within the perinecrotic region. CONCLUSION: ADC and CBF are promising imaging biomarkers for identifying perinecrotic regions, whereas CBF and APT are promising for identifying necrotic cores.


Assuntos
Amidas/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Circulação Cerebrovascular/efeitos da radiação , Imageamento por Ressonância Magnética/métodos , Lesões Experimentais por Radiação/patologia , Animais , Água Corporal/metabolismo , Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Circulação Cerebrovascular/fisiologia , Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Gadolínio , Masculino , Necrose , Prótons , Lesões Experimentais por Radiação/metabolismo , Ratos , Ratos Endogâmicos F344
16.
J Neurooncol ; 107(1): 51-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21948114

RESUMO

Standard MRI cannot distinguish between radiation necrosis and tumor progression; however, this distinction is critical in the assessment of tumor response to therapy. In this study, one delayed radiation necrosis model (dose, 40 Gy; radiation field, 10 × 10 mm(2); n = 13) and two orthotopic glioma models in rats (9L gliosarcoma, n =8; human glioma xenografts, n = 5) were compared using multiple diffusion tensor imaging (DTI) indices. A visible isotropic apparent diffusion coefficient (ADC) pattern was observed in the lesion due to radiation necrosis, which consisted of a hypointense central zone and a hyperintense peripheral zone. There were significantly lower ADC, parallel diffusivity, and perpendicular diffusivity in the necrotic central zone than in the peripheral zone (all P < 0.001). When radiation-induced necrosis was compared with viable tumor, radiation necrosis had significantly lower ADC than 9L gliosarcoma and human glioma xenografts (both P < 0.01) in the central zone, and significantly lower fractional anisotropy than 9L gliosarcoma (P = 0.005) and human glioma xenografts (P = 0.012) in the peripheral zone. Histological analysis revealed parenchymal coagulative necrosis in the central zone, and damaged vessels and reactive astrogliosis in the peripheral zone. These data suggest that qualitative and quantitative analysis of the DTI maps can provide useful information by which to distinguish between radiation necrosis and viable glioma.


Assuntos
Neoplasias Encefálicas/patologia , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Glioma/patologia , Lesões por Radiação/patologia , Animais , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Ratos , Ratos Endogâmicos F344 , Transplante Heterólogo , Células Tumorais Cultivadas
17.
Cancer Biol Ther ; 12(7): 657-63, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21811091

RESUMO

Pituitary adenomas with local invasion and high secretory activity remain a therapeutic challenge. The HIV protease inhibitor nelfinavir is a radiosensitizer in multiple tumor models. We tested nelfinavir as a radiosensitizer in pituitary adenoma cells in vitro and in vivo. We examined the effect of nelfinavir with radiation on in vitro cell viability, clonogenic survival, apoptosis, prolactin secretion, cell cycle distribution, and the PI3K-AKT-mTOR pathway. We evaluated tumor growth delay and confirmed nelfinavir's effect on the PI3K-AKT-mTOR pathway in a hind-flank model. Nelfinavir sensitized pituitary adenoma cells to ionizing radiation as shown by viability assays and clonogenic assay with an enhancement ratio of 1.2 (p < 0.05). There is increased apoptotic cell death, as determined by annexin-V expression and cleaved caspase-3 levels. Nelfinavir does not affect prolactin secretion or cell cycle distribution. In vivo, untreated tumors reached 4-fold volume in 12 days, 17 days with nelfinavir treatment, 27 days with radiation 6 Gy, and 41 days with nelfinavir plus radiation (one-way ANOVA p < 0.001). Decreased phospho-S6 on Western blotting in vitro and immunohistochemistry in vivo demonstrated nelfinavir inhibition of the PI3K-AKT-mTOR pathway. Our data suggests a promising combination therapy with nelfinavir plus radiation in pituitary adenomas, which should be investigated in clinical studies.


Assuntos
Adenoma/tratamento farmacológico , Adenoma/radioterapia , Nelfinavir/farmacologia , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/radioterapia , Radiossensibilizantes/farmacologia , Adenoma/metabolismo , Adenoma/patologia , Animais , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Experimentais , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Prolactina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Neurooncol ; 104(2): 579-87, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21327710

RESUMO

Radiation therapy (RT) for brain tumors is associated with neurocognitive toxicity which may be a result of damage to neural progenitor cells (NPCs). We present a novel technique to limit the radiation dose to NPC without compromising tumor coverage. A study was performed in mice to examine the rationale and another was conducted in humans to determine its feasibility. C57BL/6 mice received localized radiation using a dedicated animal irradiation system with on-board CT imaging with either: (1) Radiation which spared NPC containing regions; (2) Radiation which did not spare these niches; or (3) Sham irradiation. Mice were sacrificed 24 h later and the brains were processed for immunohistochemical Ki-67 staining. For the human component of the study, 33 patients with primary brain tumors were evaluated. Two intensity modulated radiotherapy (IMRT) plans were retrospectively compared: a standard clinical plan and a plan which spares NPC regions while maintaining the same dose coverage of the tumor. The change in radiation dose to the contralateral NPC-containing regions was recorded. In the mouse model, non-NPC-sparing radiation treatment resulted in a significant decrease in the number of Ki67(+) cells in dentate gyrus (DG) (P = 0.008) and subventricular zone (SVZ) (P = 0.005) compared to NPC-sparing radiation treatment. In NPC-sparing clinical plans, NPC regions received significantly lower radiation dose with no clinically relevant changes in tumor coverage. This novel radiation technique should significantly reduce radiation doses to NPC containing regions of the brain which may reduce neurocognitive deficits following RT for brain tumors.


Assuntos
Neoplasias Encefálicas/radioterapia , Irradiação Craniana/métodos , Glioblastoma/radioterapia , Células-Tronco Neurais/efeitos da radiação , Nicho de Células-Tronco/efeitos da radiação , Animais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos
19.
Proc Natl Acad Sci U S A ; 108(4): 1609-14, 2011 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21220327

RESUMO

Radiation therapy can result in bone injury with the development of fractures and often can lead to delayed and nonunion of bone. There is no prevention or treatment for irradiation-induced bone injury. We irradiated the distal half of the mouse left femur to study the mechanism of irradiation-induced bone injury and found that no mesenchymal stem cells (MSCs) were detected in irradiated distal femora or nonirradiated proximal femora. The MSCs in the circulation doubled at 1 week and increased fourfold after 4 wk of irradiation. The number of MSCs in the proximal femur quickly recovered, but no recovery was observed in the distal femur. The levels of free radicals were increased threefold at 1 wk and remained at this high level for 4 wk in distal femora, whereas the levels were increased at 1 wk and returned to the basal level at 4 wk in nonirradiated proximal femur. Free radicals diffuse ipsilaterally to the proximal femur through bone medullary canal. The blood vessels in the distal femora were destroyed in angiographic images, but not in the proximal femora. The osteoclasts and osteoblasts were decreased in the distal femora after irradiation, but no changes were observed in the proximal femora. The total bone volumes were not affected in proximal and distal femora. Our data indicate that irradiation produces free radicals that adversely affect the survival of MSCs in both distal and proximal femora. Irradiation injury to the vasculatures and the microenvironment affect the niches for stem cells during the recovery period.


Assuntos
Células da Medula Óssea/efeitos da radiação , Medula Óssea/efeitos da radiação , Fêmur/efeitos da radiação , Células-Tronco Mesenquimais/efeitos da radiação , Animais , Antígenos Ly/metabolismo , Vasos Sanguíneos/patologia , Vasos Sanguíneos/efeitos da radiação , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Ensaio de Unidades Formadoras de Colônias , Fêmur/metabolismo , Fêmur/patologia , Fibroblastos/patologia , Fibroblastos/efeitos da radiação , Radicais Livres/metabolismo , Integrina beta1/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/patologia , Osteoblastos/efeitos da radiação , Lesões Experimentais por Radiação/etiologia , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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