Normal values and within-subject variability of cardiac I-123 MIBG scintigraphy in healthy individuals: Implications for clinical studies

BACKGROUND: Although several myocardial iodine 123 metaiodobenzylguanidine (MIBG) indices are increasingly used to detect alterations in myocardial sympathetic activity in various forms of cardiac pathology, published measurements of normal values and within-subject variability are lacking. METHODS AND RESULTS: Twenty-five healthy volunteers underwent planar and single photon emission computed tomography (SPECT) imaging. Heart-mediastinum ratio (H/M) and myocardial washout were calculated from planar images comparing three different methods for the assessment of myocardial activity: (1) global region over the myocardium (cavity included), (2) global region over the myocardium (cavity excluded), and (3) fixed small myocardial region. Segmental (relative) uptake and washout were assessed by SPECT. For all MIBG indices, the interindividual variation was the lowest for methods 1 and 2. In SPECT this variation was low for relative segmental uptake compared with washout. In 9 subjects a second MIBG scintigraphy was performed after 3 months. The within-subject variability of H/M and washout assessed by planar methods 1 and 2 was 5%, whereas it was approximately 9% for planar method 3. For relative segmental uptake from SPECT, this variability was 5%. CONCLUSION: MIBG H/M (planar) and relative segmental uptake (SPECT) show a low interindividual and within-subject variability. This enables the detection of small (regional) variations in myocardial sympathetic nervous function, especially to monitor the effect of therapeutic interventions in patients with various cardiac diseases.     

Gender and symptoms in primary care practices

The authors sought to explore gender differences among patients with physical symptoms who came to see internists. The women were younger, more likely to report stress, endorsed more "other, currently bothersome" symptoms, were more likely to have a mental disorder, and were less likely to be satisfied with their care. The men were slower to improve, but there was no difference between the sexes after 3 months. There were no differences in the number, type, duration, or severity of symptoms or in the expectation of care, costs of visits, intervention received, use of health care services, or likelihood of being considered difficult by their physician. The gender of the clinician had no effect on any outcome.     

Identifying new diseases and their causes: the dilemma of illnesses in Gulf War veterans

Since the Gulf War, investigation continues of symptoms and illnesses among its veterans. Yet, identifying a specific "Gulf War Syndrome" remains elusive. With new disease entities, causal associations are relatively easily established when the condition is serious, verifiable, and has excess disease rates in specific groups. In common conditions, many excess cases are required to establish association with a specific exposure. Establishing causality in syndromes with variable symptoms is difficult because specific diagnostic algorithms must be established before causal factors can be properly investigated. Searching for an environmental cause is futile in the absence of an operational disease case definition. Common subjective symptoms (without objective physical or laboratory findings) account for over one-half of all medical outpatient visits, yet these symptoms lack an identified physical cause at least one-third of the time. Our medical care system has difficulty dealing with disorders where there is no identified anatomic abnormality or documented metabolic/physiological dysfunction.     

急性淋巴细胞白血病最新治疗策略(下)

4分子治疗分析肿瘤细胞中的分子遗传性变异及后天变异的方法正在快速成熟起来。这些方法通常涉及基因组学、转录特征性识别及蛋白质组学,有利于更深入地了解ALL的发病机理,使用于临床评估的靶向治疗全面发展。最终,这些层出不穷的新技术将营造出一个全新的个性化分子医学时代,创造出效果更好而毒性更低的治疗方案。尽管治疗方案均显示了药物介入控制细胞周期进程、基因转录、细胞运动、凋亡及细胞代谢信号通路的可行性(图1),但针对ALL的分子治疗情况(表1)仍差强人意。我们将从众多正处于临床前期或早期临床研究的分子治疗方案中,选择出那…