Novel association of thymic carcinoid with a germline mutation in a kindred with multiple endocrine neoplasia 1 (MEN1)

Multiple endocrine neoplasia 1 (MEN1) is an autosomal dominant syndrome characterized by a triad of endocrine (parathyroid, enteropancreatic and pituitary) tumors. Familial MEN1 is defined by one first-degree relative having at least one of these 3 main tumors, and is associated with germline mutations in the MEN1 gene on 11q13 in a large proportion of cases. MEN1 patients may also develop non-endocrine tumors, notably thymic carcinoid. These are rare tumors found predominantly in men, and are a major cause of death in MEN1 due to their insidious nature, lack of effective treatment and unpredictable recurrence. Prophylactic thymectomy has been advocated for prevention but continued surveillance for recurrence is necessary. Although genotype-phenotype correlation in MEN1-related thymic carcinoid is inconsistent, there is a high prevalence of truncating mutations in this condition. We describe a father and son with MEN1, associated with thymic carcinoid (father) and the truncating mutation R29X (son), which was not previously reported in MEN1-related thymic carcinoid, and review the literature about thymic carcinoids in MEN1. Our cases illustrate the importance of a high index of suspicion for early diagnosis and lifelong surveillance in MEN1, and the utility of genetic analysis in defining surveillance for MEN1-related thymic carcinoid.     

Osteogenic effect of high-frequency acceleration on alveolar bone

Mechanical stimulation contributes to the health of alveolar bone, but no therapy using the osteogenic effects of these stimuli to increase alveolar bone formation has been developed. We propose that the application of high-frequency acceleration to teeth in the absence of significant loading is osteogenic. Sprague-Dawley rats were divided among control, sham, and experimental groups. The experimental group underwent localized accelerations at different frequencies for 5 min/day on the occlusal surface of the maxillary right first molar at a very low magnitude of loading (4 με). Sham rats received a similar load in the absence of acceleration or frequency. The alveolar bone of the maxilla was evaluated by microcomputed tomography (μCT), histology, fluorescence microscopy, scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR imaging), and RT-PCR for osteogenic genes. Results demonstrate that application of high-frequency acceleration significantly increased alveolar bone formation. These effects were not restricted to the area of application, and loading could be replaced by frequency and acceleration. These studies propose a simple mechanical therapy that may play a significant role in alveolar bone formation and maintenance.     

Management of Early Node‐Positive Breast Cancer in Australia: A Multicentre Study

To examine practice patterns for breast cancer patients with limited sentinel node (SN) disease in light of the ACOSOG Z0011 results. Retrospective analysis of patients with T1‐2 breast cancer and positive sentinel lymph node biopsy (SLNB) admitted between January 2009 and December 2012. Patient demographics, tumor characteristics, and treatments were recorded. Eight hundred positive SLNBs were identified. A total of 452 (56.5%) proceeded to completion axillary lymph node dissection (cALND). cALND rate decreased from 65.1% to 49.7% from 2009–2010 to 2011–2012. cALND was performed for micrometastasis or isolated tumor cells in 39.3% in 2009–2010 and 22.2% in 2011–2012, whereas for macrometastases the rates were 83.1% and 68.6%, respectively. cALND rates diminished for both Z0011‐eligible and ‐ineligible patients. The ACOSOG Z0011 trial presentation and publication coincided with a reduction in cALND for breast cancer with limited nodal disease. There appears equipoise regarding management of macrometastatic SN disease.     

Parental smoking impairs vaccine responses in children with atopic genotypes

BACKGROUND: Gene-environment interactions play central roles in controlling postnatal maturation of immune function, but their effects on infant vaccine responses are unknown. Genetic variants associated with atopy and the environmental factor of exposure to parental smoking (PS) of tobacco independently alter immune responses. OBJECTIVE: We sought to investigate the hypothesis that genetic variants associated with atopy and their interaction with PS influence infant vaccine responsiveness. METHODS: In 200 infants with parental atopic history, relationships were sought between polymorphisms in the IL-4, IL-4 receptor alpha (IL-4Ralpha), and IL-13 genes; PS; and immune responses to diphtheria/tetanus vaccination. RESULTS: Analyses stratified by PS unmasked negative associations between atopic alleles of these genes and vaccine outcomes. The most consistent involved the IL-4Ralpha 551 QR/QQ genotypes, which were associated with reduced IgG levels (P = .02) and T-cell responses (IFN-gamma, P = .002; IL-10, P = .01; 1L-13, P = .01; IL-5, P = .06) to tetanus toxoid and parallel reductions in polyclonal T-cell responses and innate immune responses in PS-exposed infants. CONCLUSION: PS potentiates suppressive effects of variants in immune response genes in children. These effects are not observed in the absence of this exposure. Ultimately, this finding might have implications for infant vaccination in countries with high smoking rates. It might also have broader implications in relation to environmental toxicology because it demonstrates specific mechanisms through which the developing immune system might be differentially sensitive to low-level toxicant exposures. CLINICAL IMPLICATIONS: PS interacts with genes associated with atopy to impair vaccine responses. These interactions might have vaccine design and public health implications.     

A Nonlinear Model of Cardiac Autonomic Control in Obstructive Sleep Apnea Syndrome

Using the Volterra–Wiener approach, we employed a minimal model to quantitatively characterize the linear and nonlinear effects of respiration (RCC) and arterial blood pressure (ABR) on heart rate variability (HRV) in normal controls and subjects with moderate-to-severe obstructive sleep apnea syndrome (OSAS). Respiration, R–R interval (RRI), blood pressure (BP) and other polysomnographic variables were recorded in eight normal controls and nine OSAS subjects in wakefulness, Stage 2 and rapid eye-movement sleep. To increase respiratory and cardiovascular variability, a preprogrammed ventilator delivered randomly timed inspiratory pressures that were superimposed on a baseline continuous positive airway pressure. Except for lower resting RRI in OSAS subjects, summary statistical measures of RRI and BP and their variabilities were similar in controls and OSAS. In contrast, RCC and ABR gains were significantly lower in OSAS. Nonlinear ABR gain and the interaction between respiration and blood pressure in modulating RRI were substantially reduced in OSAS. ABR gain increased during sleep in controls but remained unchanged in OSAS. These findings suggest that normotensive OSAS subjects have impaired daytime parasympathetic and sympathetic function. Nonlinear minimal modeling of HRV provides a useful, insightful, and comprehensive approach for the detection and assessment of abnormal autonomic function in OSAS. Supported by NIH Grants HL-58725, EB-001978, and M01 RR-43