RESUMO
The objective of this study was to estimate the subsequent cancer risk of women after receiving hysterosalpingography (HSG) by conducting a nationwide retrospective cohort study. We identified a study cohort of 4,371 patients who had had a HSG examination and a comparison cohort of 17,484 women without HSG examination between 1998 and 2005. Both cohorts were followed up with until the end of 2010 to measure the incidence of cancer. The risk of developing cancer for patients with HSG was assessed using the Cox proportional hazard model. In the multivariate analyses, the HSG cohort did not have a significantly greater risk of cancer (Hazard Ratio [HR] = 1.02, 95% CI = 0.79-1.31) than the non-HSG cohort. The HR was highest for genital cancer (HR = 1.32, 95% CI = 0.77-2.25), followed by urinary system cancer (HR = 1.11, 95% CI = 0.23-5.40), and abdominal cancer not involving the GU system (HR = 1.04, 95% CI = 0.53-2.03), all of which were non-significant elevations. The cancer incidence rates, especially that for urinary system cancer, were increased in the HSG cohort, but the increase in cancer incidence was small and not statistically significant.
Assuntos
Tubas Uterinas/efeitos da radiação , Histerossalpingografia/efeitos adversos , Neoplasias Induzidas por Radiação/epidemiologia , Útero/efeitos da radiação , Adulto , Distribuição por Idade , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Análise Multivariada , Programas Nacionais de Saúde/estatística & dados numéricos , Neoplasias Induzidas por Radiação/complicações , Vigilância da População , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Risco , TaiwanRESUMO
BACKGROUND: The onsets of needling sensation introduced by acupuncture stimulus can vary widely from subject to subject. This should be explicitly accounted for by the model blood oxygenation-level dependent (BOLD) time course used in general linear model (GLM) analysis to obtain more consistent across-subject group results. However, in standard GLM analysis, the model BOLD time course obtained by convolving a canonical hemodynamic response function with an experimental paradigm time course is assumed identical across subjects. Although some added-on properties to the model BOLD time course, such as temporal and dispersion derivatives, may be used to account for different BOLD response onsets, they can only account for the BOLD onset deviations to the extent of less than one repetition time (TR). METHODS: In this study, we explicitly manipulated the onsets of model BOLD time course by shifting it with -2, -1, or 1 TR and used these temporally shifted BOLD model to analyze the functional magnetic resonance imaging (fMRI) data obtained from three acupuncture fMRI experiments with GLM analysis. One involved acupuncture stimulus on left ST42 acupoint and the other two on left GB40 and left BL64 acupoints. RESULTS: The model BOLD time course with temporal shifts, in addition to temporal and dispersion derivatives, could result in better statistical power of the data analysis in terms of the average correlation coefficients between the used BOLD models and extracted BOLD responses from individual subject data and the T-values of the activation clusters in the grouped random effects. CONCLUSIONS: The GLM analysis with ordinary BOLD model failed to catch the large variability of the onsets of the BOLD responses associated with the acupuncture needling sensation. Shifts in time with more than a TR on model BOLD time course might be required to better extract the acupuncture stimulus-induced BOLD activities from individual fMRI data.
Assuntos
Acupuntura , Hemodinâmica/fisiologia , Imageamento por Ressonância Magnética , Oxigênio/sangue , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Carryover effects can contaminate ON/OFF BOLD contrasts designated in an fMRI experiment. Yet, the ON/OFF contrasts are essential to facilitate statistical analysis based on the significance of contrast levels. Here, we conducted an fMRI experiment with acupuncture stimulation applied on ST42 acupoint as well as with tactile stimulation on its skin surface. Experiment consisted of three two-block acupuncture and one two-block tactile fMRI runs. Each block started with 26-sec OFF period followed by either 26-sec needle manipulation in the acupuncture runs or by scratching skin surface with sand paper in the tactile. To test if carryover effects could alter the BOLD contrasts, we analyzed different portions of fMRI data using GLM method. Our results showed analyses on different portions of acupuncture fMRI data gave significantly different results. Statistical parametric maps of group random effects resulted from the analysis on the very first fMRI trial formed the broadest coverage of the active brain areas. BOLD model time course also best explained the adjusted raw time course at peak active voxel (coefficient of determination = 0.88). Analyses on other portions of fMRI data only selected subset of the active brain areas delineated by the analysis on the very first data trial and the BOLD model only mildly accounted for the adjusted raw time courses. In tactile runs, results were more consistent across analyses. Therefore, in fMRI experiments with strong carryover effects, a single-block experimental design with multiple repetitions, separated by long enough periods of time, should be more suitable to extract task BOLD effects.
Assuntos
Acupuntura/métodos , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Adulto , Encéfalo/anatomia & histologia , Feminino , Humanos , Masculino , Agulhas , Oxigênio/sangue , Valores de Referência , SensaçãoRESUMO
The electrical stimulation of meridian points in rats inhibits the withdrawal reflex of the nociceptive tail. Its pain mechanisms are well-documented. Moreover, electroacupuncture (EA) at special abdominal acupoints has been shown to induce a short-term hypoglycemia effect in streptozotocin diabetic rats. The Zusanli and Zhongwan acupoints have been widely used in traditional Chinese medicine to relieve symptoms of diabetes mellitus. It is still unclear whether they can affect extracellular glucose and lactate metabolites at the cellular level. The aim of this study is to evaluate these effects using a rat model for the analysis of extracellular neurochemicals. First, electrical stimulus of 2 ms 2 Hz square pulses (30 minutes) was applied to anesthetized intact rats (n = 7) at the Zusanli points. One and a half hours later, a second electrical stimulus (2 Hz pulses, 30 minutes) was delivered to two of the rats at the same spot. Another two rats received a different stimulation (100 Hz pulses, 30 minutes) at the same location. In the final three rats, a second electrical stimulus of 2 Hz pulses was delivered to non-acupoints. An automated micro-blood sample collector was used to examine the glucose, pyruvate and lactate concentrations. The EA signal has an influence on the biologic process of energy metabolism by mediating dynamic extracellular neurochemical changes. The EA at limb acupoints of the lower limbs induces a decrease in glucose, an increase in lactate metabolites and a decrease in the lactate/glucose ratio. Moreover, the increased lactate/glucose ratio suggests that the cell has an increased anaerobic glucose metabolism.
Assuntos
Glicemia/análise , Eletroacupuntura , Metabolismo Energético/fisiologia , Ácido Láctico/sangue , Ácido Pirúvico/sangue , Pontos de Acupuntura , Animais , Meridianos , Ratos , Ratos Sprague-DawleyRESUMO
Melanin was extracted from tea leaves (Thea sinensis Linn.) for the first time. Characterization of melanin proved similarity of the original compound to standard melanin. The Langmuir adsorption isotherms for gadolinium (Gd) binding were obtained using melanin. Melanin-Gd preparation demonstrated low acute toxicity. LD(50) for this preparation was in a range of 1250-1500 mg/kg in mice. Magnetic Resonance Imaging (MRI) properties of melanin itself and melanin-Gd complexes have been estimated. Gd free melanin fractions possess slighter relaxivity compared with its complexes. The relaxivity of lower molecular weight fraction was two times higher than relaxivity of Gd(DTPA) standard. Postcontrast images demonstrate that oral administration of melanin complexes in concentration 0.1 mM provides essential enhancement to longitudinal relaxation times (T(1))-weighted spin echo image. The required contrast and delineation of the stomach wall demonstrated uniform enhancement of MRI with proposed melanin complex.