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The current paper describes the age, period and cohort effects on breast cancer mortality in Taiwan. Female breast cancer mortality data were collected from the Taiwan death registries for 1971-2010. The annual percentage changes, age- standardised mortality rates (ASMR) and age-period-cohort model were calculated. The mortality rates increased with advancing age groups when fixing the period. The percentage change in the breast cancer mortality rate increased from 54.79% at aged 20-44 years, to 149.78% in those aged 45-64 years (between 1971-75 and 2006-10). The mortality rates in the 45-64 age group increased steadily from 1971 to 1975 and 2006-10. The 1951 birth cohorts (actual birth cohort; 1947-55) showed peak mortalities in both the 50-54 and 45-49 age groups. We found that the 1951 birth cohorts had the greatest mortality risk from breast cancer. This might be attributed to the DDT that was used in large amounts to prevent deaths from malaria in Taiwan. However, future researches require DDT data to evaluate the association between breast cancer and DDT use.
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Neoplasias da Mama/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/induzido quimicamente , Estudos de Coortes , DDT/toxicidade , Feminino , Humanos , Pessoa de Meia-Idade , Mortalidade/tendências , Taiwan/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: To determine whether plasminogen activators (PAs) are involved in the pathologic process of toxoplasmosis. MATERIALS AND METHODS: Out of 220 pregnant women the study included 26 with a diagnosis of toxoplasmosis: six based on seropositivity for Toxoplasma gondii IgM and 20 based on seropositivity for T. gondii IgG. We measured serum activities and protein levels of PAs by casein zymography and Western blotting, respectively. RESULTS: Serum PAs were higher in healthy pregnant women than in their healthy nonpregnant counterparts. Furthermore, serum PAs were significantly higher in pregnant women infected with T. gondii than in their healthy counterparts. CONCLUSION: PAs participate in the pathogenesis of toxoplasmosis in pregnant women and may be useful markers of T. gondii infection.
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Ativadores de Plasminogênio/sangue , Complicações Parasitárias na Gravidez/sangue , Toxoplasmose/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Gravidez , Terceiro Trimestre da Gravidez , Diagnóstico Pré-Natal , Toxoplasma/imunologiaRESUMO
OBJECTIVE: The purpose of this study was to investigate whether the effect of treatment with hyaluronic acid (HA) on cartilage in osteoarthritis (OA) can be determined by measuring the magnetic resonance (MR) T2 value of cartilage in an anterior cruciate ligament transection (ACLX) animal model. METHOD: Eighteen male Sprague Dawley rats were separated randomly into three groups (n=6 for each group). Group 1 was given ACLX and intra-articular (IA) normal saline (NS) injection (ACLX+NS), group 2 was given ACLX and IA HA injection (ACLX+HA), and group 3 was the sham control. The ACLX+NS and ACLX+HA groups received ACLX on the right knee at 8 weeks of age and were then treated with IA NS or HA injection once a week, respectively, for 4 weeks starting at 13 weeks of age. In the sham-control group, the right knee joint was opened surgically but ACLX was not performed at 8 weeks of age. MR T2 measurements were obtained on all rats at 8, 12, and 21 weeks of age, and histological Mankin scoring was performed at 21 weeks of age. RESULTS: Five weeks after the 4-week treatment, the MR T2 value of the ACLX right knee cartilage was significantly lower in ACLX+HA (29.58+/-1.12ms) than in ACLX+NS (32.04+/-1.39ms) (P<0.05). Five weeks after the 4-week treatment, the Mankin score of the ACLX right knee was significantly lower in ACLX+HA (3.3+/-0.81) than in ACLX+NS (7.3+/-1.03) (P<0.001). The T2 value was significantly and positively correlated with the Mankin score in the ACLX+NS (rho=0.77, P<0.05) and ACLX+HA (rho=0.69, P<0.05) groups. CONCLUSION: This study demonstrates the feasibility of quantitative MR T2 measurement in the early assessment of HA treatment efficiency in a cartilage degeneration model.
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Adjuvantes Imunológicos/uso terapêutico , Lesões do Ligamento Cruzado Anterior , Cartilagem Articular/patologia , Ácido Hialurônico/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Ligamento Cruzado Anterior/cirurgia , Artrite Experimental/patologia , Cartilagem Articular/efeitos dos fármacos , Modelos Animais de Doenças , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/farmacologia , Injeções Intra-Articulares , Imageamento por Ressonância Magnética/métodos , Masculino , Osteoartrite do Joelho/patologia , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: The magnetic resonance (MR) T2 value of the cartilage, which has been shown in the articular cartilage to correlate with collagen fiber orientation and water content, may be helpful for early detection of chondropathy. However, the measurement and significance of MR T2 value for knee meniscus have not been well established. The purpose of this study was to investigate whether the MR T2 values in the diverse zones of the posterior horn of the knee meniscus differ between sexes in a young healthy population. METHOD: Twenty healthy volunteers, 10 men and 10 women (aged from 22 to 32 years), were enrolled for MR imaging of the right knee menisci. The T2 values of the posterior horns of the medial and lateral knee menisci were measured for the white zone, red/white zone, and red zone on images acquired with fat-suppressed multislice turbo spin-echo sequence at 3.0 T. RESULTS: The T2 value, with medial and lateral menisci considered together, increased significantly from the inner white zone (T2=8.02+/-0.60 ms), to the red/white zone (T2=8.78+/-0.99 ms), and to the outer red zone (T2=12.22+/-0.92 ms) of the posterior horns of the menisci (P<0.001). A generalized estimating equation method and multiple linear regression model showed that the T2 values averaged for the medial and lateral menisci together in the red and red/white zones were significantly lower in men than in women by 1.320 ms (P=0.002) and 0.865 ms (P<0.001), respectively, while the white zone showed no significant difference (P=0.694) between men (8.08+/-0.63 ms) and women (7.98+/-0.60 ms). CONCLUSION: Zonal and sex differences in the MR T2 values in the posterior horns of the knee menisci exist in the young healthy population. These differences may be associated with sex differences in the occurrence of knee osteoarthritis.
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Cartilagem Articular/patologia , Articulação do Joelho/patologia , Osteoartrite do Joelho/patologia , Adulto , Cartilagem Articular/fisiologia , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/patologia , Meniscos Tibiais/fisiologia , Osteoartrite do Joelho/fisiopatologia , Valores de Referência , Fatores Sexuais , Adulto JovemRESUMO
OBJECTIVE: Both animal and human studies using magnetic resonance imaging (MRI) show that cartilage degeneration increases the T2 value. However, it is unclear whether the T2 value correlates linearly with water content in cartilage with osteoarthritis. The purpose of this study was to investigate the relationship between the T2 value and water content using an animal model of cartilage injury measured at 4.7 T. DESIGN: Thirty Sprague Dawley rats were randomly separated into three groups (n=10 for each group). Group 1 rats were not operated on (control). Group 2 rats received a sham operation, and group 3 rats received an anterior cruciate ligament (ACL) transection. Six rats of each group were randomly assigned to T2 measurement and later subjected to ex vivo analysis of the relative water content of the knee cartilage. The other four rats in each group were killed, and the severity of cartilage degeneration was examined histologically. The knees of the six rats in the ACL transection group were imaged sequentially 4 and 13 weeks after ACL transection, and the relative water content was measured at 13 weeks. RESULTS: The cartilage T2 value was significantly higher 4 and 13 weeks after ACL transection in the operated knees than in the knees of the control and sham groups. The cartilage T2 value was significantly higher at 13 weeks than at 4 weeks in the operated knees. The T2 value was strongly positively correlated with the relative water content (R=0.885, P<0.0001). CONCLUSION: The trend of changes in the T2 values is consistent with an increase in the relative water content in our cartilage degeneration model. This model has potential use for the clinical evaluation of osteoarthritis.
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Artrite Experimental/complicações , Doenças das Cartilagens/etiologia , Cartilagem Articular/patologia , Edema/etiologia , Osteoartrite/complicações , Animais , Lesões do Ligamento Cruzado Anterior , Artrite Experimental/etiologia , Água Corporal , Doenças das Cartilagens/diagnóstico , Edema/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND AND PURPOSE: Patients with carbon monoxide (CO) intoxication exhibit progressive WM changes that are not well-understood. The purpose of this study was to detect longitudinal WM changes using voxelwise diffusional kurtosis imaging in patients with CO intoxication from the acute-to-chronic stage after CO intoxication. MATERIALS AND METHODS: Twenty-four patients with CO intoxication and 21 age- and sex-matched healthy controls were enrolled in this study. Diffusional kurtosis imaging was performed on all subjects and was conducted repeatedly in patients at 1 week and 1, 3, and 9 months after CO intoxication. Voxelwise diffusional kurtosis imaging analysis was performed to detect global WM changes in the patients with and without WM lesions. Receiver operating characteristic analysis was performed to compare the performance of diffusional indices in differentiating patients with delayed neuropsychiatric sequelae from patients without them. RESULTS: In voxelwise analysis, progressive WM changes were detected in patients with WM lesions. In the acute phase, WM injuries were found mainly in the dopaminergic pathways at 1 week, whereas in the chronic stage, WM injuries extended toward subcortical areas from 1 to 9 months. However, no significant WM change was noted in patients without WM lesions during the 9 months after CO intoxication. Moreover, receiver operating characteristic analysis demonstrated that axial kurtosis and mean kurtosis values had better performance than other diffusional indices in differentiating patients with delayed neuropsychiatric sequelae from patients without them at 1 week after CO intoxication. CONCLUSIONS: Voxelwise diffusional kurtosis imaging analysis was helpful to longitudinally investigate WM changes and predict the prognosis of patients after CO intoxication.
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Encéfalo/diagnóstico por imagem , Intoxicação por Monóxido de Carbono/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Neuroimagem/métodos , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/patologia , Intoxicação por Monóxido de Carbono/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Substância Branca/patologiaRESUMO
It is well known that the combination of cyclosporine A (CsA) with rapamycin produces serious nephrotoxicity. Herein we suggest a mechanism by which rapamycin increases CsA nephrotoxicity. Previously, we demonstrated that activation of Akt/protein kinase B protects against cyclosporine nephrotoxicity and prevents apoptosis. Recently, it has been shown that Akt phosphorylation activates mammalian target of rapamycin (m-TOR) and inhibits programmed cell death including apoptosis and autophagy. Akt is believed to be an importance factor for cell survival. In theory, blockade of the Akt pathway through inhibition of m-TOR may increase cyclosporine-induced apoptosis. We added cyclosporine and rapamycin to cultures of ER52K proximal renal tubule cells, leading to a significantly decreased survival rate. The nephrotoxicity was associated with increased apoptosis by cleavage of caspase-3 and decreased phosphorylation of m-TOR and AktSer473, findings that support this hypothesis. This nephrotoxic effect may explain the clinical finding that patients treated with rapamycin alone exhibited better renal function than those treated with concomitant cyclosporine therapy.
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Ciclosporina/toxicidade , Imunossupressores/uso terapêutico , Túbulos Renais Proximais/efeitos dos fármacos , Sirolimo/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/toxicidade , Túbulos Renais Proximais/patologia , Sirolimo/efeitos adversosRESUMO
Diffusion imaging acquired with echo-planar imaging (EPI) is usually performed with parallel imaging to reduce geometric distortions, especially at high fields. This study reports the occurrence of pseudolesions in EPI with parallel imaging. The unfolding artifacts are attributed as arising from a mismatch between RF sensitivity profiles and distorted acquisition data in the presence of susceptibility effects, plus strong signals on the b=0 images. Examples of pseudolesions from the eyeballs are shown, and remedies are suggested.
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Algoritmos , Artefatos , Imagem Ecoplanar/métodos , Olho/anatomia & histologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Oculares/diagnóstico , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND AND PURPOSE: The relationship between the local blood oxygen level-dependent (BOLD) signals caused by neural stimulation (fBOLD) and the global BOLD signals induced by hypercapnia (hBOLD) has not been fully investigated. In this study, we examine whether fBOLD is modulated by hBOLD signals, by means of experiments using a relatively wide range of inhaled carbon dioxide (CO(2)) for a long duration of 5 minutes. MATERIALS AND METHODS: Ten healthy volunteers were recruited, each undergoing 6 separate experiments by inhaling gas mixtures with different fractions of CO(2) (room air, 3%-7%). Each experiment contained 3 phases, prehypercapnic, hypercapnic, and posthypercapnic, during which boxcar visual stimulus was given. The local fBOLD signals were measured from areas showing activation patterns highly correlated with the visual stimulus paradigm, whereas the global hBOLD signals were measured from areas showing no visual activations. Percentage changes in fBOLD during transient-state hypercapnia and steady-state hypercapnia were both investigated in response to varying degrees of hypercapnic perturbations. RESULTS: The hBOLD signals increased with increase of inhaled CO(2) fractions. The duration for the hBOLD signals to reach steady state prolonged with increase of inhaled CO(2) fractions. Normalized fBOLD ratio was inversely related to the inhaled CO(2) during steady-state hypercapnia but showed positive association with hBOLD during transient-state hypercapnia. CONCLUSION: Our study concludes that the steady-state fBOLD signal intensity is dependent on and inversely related to the hBOLD signals. Previous reports documenting independent and additive relationships between hBOLD and fBOLD may likely be due to transient-state observations.
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Encéfalo/fisiopatologia , Dióxido de Carbono/sangue , Potenciais Evocados , Hipercapnia/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Oxigênio/sangue , Administração por Inalação , Adulto , Artefatos , Dióxido de Carbono/administração & dosagem , Estimulação Elétrica/métodos , Feminino , Humanos , MasculinoRESUMO
The purpose of this study is to assess the efficacy of hyperbaric oxygen therapy (HBOT) in patients with delayed neuropsychiatric syndrome (DNS) caused by carbon monoxide (CO) inhalation using diffusion tensor magnetic resonance (MR) imaging and neuropsychological test. Conventional and diffusion tensor brain MR imaging exams were performed in six patients with DNS immediately before and 3 months after the HBOT to obtain fractional anisotropy (FA) values. Six age- and sex-matched normal control subjects also received MR exams for comparison. Mini-Mental State Examination (MMSE) was also performed in patients immediately before and 3 months after the HBOT. A significantly higher mean FA value was found in control subjects as compared with the patients both before and 3 months after the HBOT (P < 0.001). The mean FA value 3 months after the HBOT was also significantly higher than that before the HBOT in the patient group (P < 0.001). All of the patients regained full scores in the MMSE 3 months after the HBOT. Diffusion tensor MR imaging can be a quantitative method for the assessment of the white matter change and monitor the treatment response in patients of CO-induced DNS with a good clinical correlation. HBO may be an effective therapy for DNS.
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Sintomas Afetivos/terapia , Intoxicação por Monóxido de Carbono/terapia , Transtornos Cognitivos/terapia , Doenças Desmielinizantes/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Oxigenoterapia Hiperbárica , Bainha de Mielina/patologia , Adulto , Sintomas Afetivos/induzido quimicamente , Sintomas Afetivos/patologia , Anisotropia , Intoxicação por Monóxido de Carbono/patologia , Intoxicação por Monóxido de Carbono/psicologia , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/patologia , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/psicologia , Transtorno Depressivo/complicações , Transtorno Depressivo/psicologia , Feminino , Seguimentos , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/patologia , Transtornos dos Movimentos/terapia , Testes Neuropsicológicos , Tentativa de Suicídio , Fatores de TempoRESUMO
UNLABELLED: The aim of this study was designed to investigate the usefulness of thallium-201 single photon emission computed tomography (SPECT) in predicting response of intensity-modulated radiation therapy (IMRT) for recurrent oral squamous cell carcinoma (OSCC). PATIENTS, METHODS: Thirty-one patients with histologically proven recurrent OSCC were recruited. Before IMRT, all patients underwent SPECT at 15 min and 120 min after intravenous injection 111 MBq of thallous chloride ((201)Tl). Tumour uptake was measured with the semiquantitative early ratio (ER), delayed ratio (DR), and retention index (RI). The patients were classified into responder (complete response and partial response) and non-responder (stable disease and progressive disease) groups according to the tumour response evaluated by the Response Evaluation Criteria in Solid Tumors guidelines. RESULTS: As comparing DR and RI between the two groups, both parameters were significantly higher in the responder group. When a DR of 1.75 was used as a cutoff value for the responders, the receiver operating characteristic (ROC) analyses revealed sensitivity and specificity of 79% and 75%, respectively. At a cutoff value for the responders of a RI of 78.5%, the ROC analyses showed sensitivity and specificity of 95% and 83%, respectively. CONCLUSION: Our results suggest that (201)Tl-SPECT, as measured by the DR or RI has clinical potential in predicting response of IMRT for patients with recurrent OSCC. The ROC curve analyses further suggest that RI may be superior to DR in distinguishing responders from non-responders.
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Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/radioterapia , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/radioterapia , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , RecidivaRESUMO
AIMS: Public controversy regarding the potential overdiagnosis and overmedication of children with attention-deficit/hyperactivity disorder (ADHD) has continued for decades. This study used the National Health Insurance Research Database of Taiwan (NHIRD-TW) to explore trends in ADHD diagnosis in youths and the proportion of those receiving medication, with the aim of determining whether ADHD is overdiagnosed and overmedicated in Taiwan. METHOD: Youths (age ≤18 years) who had at least two NHIRD-TW claims records with ADHD diagnosis between January 2000 and December 2011 were selected as the subject cohort. In total, the study sample comprised 145 018 patients with ADHD (mean age at a diagnosis of ADHD: 7.7 ± 3.1 years; 21.4% females). The number of cases of ADHD were calculated annually for each year (from 2000 to 2011), and the number of cases per year who received medication was determined as those with at least one record of pharmacotherapy (immediate-release methylphenidate, osmotic controlled-release formulation of methylphenidate, and atomoxetine) in each year. RESULTS: The prevalence rates of a diagnosis of ADHD in the youths ranged from 0.11% in 2000 to 1.24% in 2011. Compared with children under 6 years of age, the ADHD diagnosis rates in children aged between 7 and 12 years (ratio of prevalence rates = 4.36) and in those aged between 13 and 18 years (ratio of prevalence rates = 1.42) were significantly higher during the study period. The prevalence in males was higher than that in females (ratio of prevalence rates = 4.09). Among the youths with ADHD, 50.2% received medications in 2000 compared with 61.0% in 2011. The probability of receiving ADHD medication increased with age. More male ADHD patients received medications that females patients (ratio of prevalence rates = 1.16). CONCLUSIONS: The rate of ADHD diagnosis was far lower than the prevalence rate (7.5%) identified in a previous community study using face-to-face interviews. Approximately 40-50% of the youths with ADHD did not receive any medications. These findings are not consistent with a systematic public opinion about overdiagnosis or overmedication of ADHD in Taiwan.
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Inibidores da Captação Adrenérgica/uso terapêutico , Cloridrato de Atomoxetina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Uso Excessivo dos Serviços de Saúde/estatística & dados numéricos , Metilfenidato/uso terapêutico , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Vigilância da População , Prevalência , Taiwan/epidemiologiaRESUMO
UNLABELLED: The AIM of this prospective study was to evaluate the usefulness of the thallium-201 ( (201) Tl) thyroid scan in the detection of malignancy in cold thyroid nodules whose status was equivocal following palpation fine-needle aspiration cytology (FNAC). PATIENTS, METHODS: Fifty-one patients with clinically palpable solitary cold thyroid nodules classified as non-diagnostic or suspicious following biopsy underwent (201) Tl thyroid scans. Each scan was performed 15 min (early scan) and 3 h (delayed scan) after an intravenous administration of 74 MBq (201) Tl. Thallium uptake in the nodules was visually assessed and scored on a three point scale, with a grade of three defining malignancy. All patients underwent surgery and the histopathology of nodule tissues were compared with results of the scans. RESULTS: Fifty-one nodules were examined. Forty were benign and 11 were malignant. For early scans, the diagnostically relevant parameters were: sensitivity (100%), specificity (75%), and accuracy (80%). Corresponding findings for the delayed scan were: 91%, 98%, and 96%. CONCLUSION: The (201) Tl scan is useful for detecting malignancy in cold thyroid nodules classified as nondiagnostic or suspicious lesions by FNAC.
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Radioisótopos de Tálio , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Biópsia por Agulha Fina , Feminino , Humanos , Masculino , Cintilografia , Reprodutibilidade dos TestesRESUMO
It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.
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MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.
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Paclitaxel has been found to exhibit cytotoxic and antitumor activity. There is little information regarding the mechanisms of apoptotic-inducing effect of paclitaxel on human osteogenic sarcoma U-2 OS cells. Several key regulatory proteins are involved in the initiation of apoptosis. Caspase-3 plays a direct role in proteolytic cleavage of cellular proteins responsible for progression to apoptosis. We examined the effect of paclitaxel on the cell cycle arrest and apoptosis in U-2 OS cells using flow cytometric analysis and Western blotting. We also measured the inhibition of paclitaxel-induced apoptosis and the caspase-3 activity by the broad-spectrum caspase inhibitor z-VAD-fmk on U-2 OS cells. The increased levels of casapse-3 were also confirmed by cDNA microarray. Our observations were: (1) paclitaxel treatment resulted in G2/M-cycle arrest in U-2 OS cells; (2) time and dose dependent apoptosis of U-2 OS cells was induced by paclitaxel; (3) in U-2 OS cells, z-VAD-fmk blocked the paclitaxel-induced apoptosis and caspase-3 activation. These results suggest that paclitaxel-induced G2/M-cycle arrest of the G2/M phase and apoptosis via a caspase-3 pathway in U-2 OS cells.
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Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Caspases/fisiologia , Osteossarcoma/tratamento farmacológico , Paclitaxel/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Neoplasias Ósseas/patologia , Caspase 3 , Inibidores de Caspase , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ativação Enzimática , Humanos , Osteossarcoma/patologiaRESUMO
AIMS: To assess gastric cancer risk and clinical-pathological factors associated with genetic polymorphisms of MK, IL-4, p16, p21 and p53 genes. METHODS: A retrospective study was conducted for 123 patients who had recently developed primary gastric cancer. Clinical data and pathological findings were collected, genetic polymorphisms of MK, IL-4, p16, p21 and p53 genes were analysed, and the associations of genetic polymorphisms with gastric cancer carcinogenesis were evaluated. RESULTS: There was significant association of genetic polymorphisms between gastric cancer and control groups in p53 genes. After further stratification of the cancer group into different clinical-pathologic parameters, there were significant associations in the sex and LN involvement groups in MK gene; alcohol consumption group in p16 gene; age and cell differentiation groups in p21 gene; age and tumour location groups in p53 gene; but we fail to find any significant association with IL-4 gene polymorphisms. CONCLUSIONS: Genetic susceptibility testing is a tool to evaluate the association of genetic polymorphisms with gastric cancer carcinogenesis.
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Inibidor de Quinase Dependente de Ciclina p21/genética , Citocinas/genética , Genes p16 , Genes p53 , Interleucina-4/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Midkina , Polimorfismo Genético , TaiwanRESUMO
By using deflectometry of a longitudinal probe pulse and reflective interferometry of a transverse probe pulse to resolve the spatiotemporal distribution of the preformed plasma, we characterize and control the plasma density distribution near the target surface for the development of solid-target x-ray lasers. We show that the use of prepulses in an ignitor-heater scheme can increase the scale length of the preformed plasma and how the effect varies with target materials. Many important issues crucial to x-ray lasing such as electron density distribution, electron temperature, and the optimal timing between pumping pulses can be resolved with these methods.