Density and Proximity of Fast Food Restaurants and Body Mass Index Among African Americans

Objectives. The purpose of this study was to address current gaps in the literature by examining the associations of fast food restaurant (FFR) density around the home and FFR proximity to the home, respectively, with body mass index (BMI) among a large sample of African American adults from Houston, Texas.Methods. We used generalized linear models with generalized estimating equations to examine associations of FFR density at 0.5-, 1-, 2-, and 5-mile road network buffers around the home with BMI and associations of the closest FFR to the home with BMI. All models were adjusted for a range of individual-level covariates and neighborhood socioeconomic status. We additionally investigated the moderating effects of household income on these relations. Data were collected from December 2008 to July 2009.Results. FFR density was not associated with BMI in the main analyses. However, FFR density at 0.5, 1, and 2 miles was positively associated with BMI among participants with lower incomes (P ≤ .025). Closer FFR proximity was associated with higher BMI among all participants (P < .001), with stronger associations emerging among those of lower income (P < .013) relative to higher income (P < .014).Conclusions. Additional research with more diverse African American samples is needed, but results supported the potential for the fast food environment to affect BMI among African Americans, particularly among those of lower economic means.Obesity and its associated health conditions are a growing problem in the United States, with obesity prevalence having more than doubled since the 1960s.1 The health care cost of Americans’ growing waistlines is substantial and expected to top $860 billion by 2030.2 Racial/ethnic disparities in obesity are of particular concern for the nation’s health, with African Americans experiencing the highest prevalence of obesity relative to other racial/ethnic groups.1 The National Health and Nutrition Examination Survey from 2009 to 2010 indicated that 38.8% of African American men and 58.5% of African American women were obese compared with 36.2% of non-Hispanic White men and 32.2% of non-Hispanic White women.3 Racial/ethnic disparities have also been cited for body mass index (BMI), with the gap in BMI growth widening between African Americans and Whites in recent decades.4To better understand the factors associated with these trends, researchers and policymakers are paying increased attention to the retail food environment. The growing availability of low-cost, calorie-dense consumables from fast food restaurants (FFRs) is one of the factors implicated in the nation’s rising BMI.5–7 The availability of FFRs may be particularly relevant to the growing racial/ethnic disparities in BMI because several studies support a higher density of FFRs among predominately African American neighborhoods relative to predominately White neighborhoods.8–11 Moreover, at least 1 study reports stronger relations between fast food availability and fast food consumption among non-White versus White populations.12 Thus, African Americans may be more likely to consume fast food if it is available, and it may be more available to them because FFRs tend to be clustered in African American neighborhoods. Not surprisingly, greater fast food consumption is associated with higher BMI.13–15Several studies examined associations between the availability of fast food and BMI. Fast food availability was most commonly conceptualized as the density of FFRs near a person’s home, work, or school environment. Findings about the associations of FFR density with BMI and overweight or obesity status, however, were mixed,5,11 with some studies supporting positive associations,16–19 and others citing null results.14,20 Less commonly, studies conceptualized fast food availability as the proximity of the closest FFR to a person’s home. Studies taking this approach yielded mixed results regarding relations between FFR proximity and fast food consumption,21,22 as well as between FFR proximity and BMI or obesity status.11,23 Unfortunately, most of these studies focused predominately on White populations, and many had methodological limitations (e.g., self-reported BMI) that could have contributed to mixed results.5,11 We found only a single study that focused on an all-African American sample, which yielded null results regarding associations between FFR density and BMI.24 Although this study had several strengths, including a sample of more than 4500 African Americans and investigator-measured BMI, limitations included only 1 conceptualization of FFR availability (FFR density), and the use of Euclidean distances (“as the crow flies”) in density buffer calculation, which may be less realistic than buffers based on road networks (i.e., the only places along which FFRs can be found).5 In addition, we found no previous studies that examined whether associations between FFR availability and BMI were moderated by household income. Because reasons cited for frequent fast food consumption include both accessibility and affordability,6 it might be that relations of FFRs and BMI are stronger among those of lower economic means for whom fast food might be more affordable than other dining options. Therefore, additional research is needed to better understand the relations of fast food availability and BMI among African Americans.The purpose of this study was to address current gaps in the literature by examining the associations of FFR density around the home and FFR proximity to the home, respectively, with BMI among a large sample of African American adults from Houston, Texas. We additionally investigated the moderating effects of household income on these relations.     

Cardiogenic shock due to papillary muscle rupture in acute myocardial infarction

We report a case of papillary muscle rupture complicating acute myocardial infarction which resulted in acute cardiogenic shock. The patient underwent urgent replacement of the mitral valve and made an uncomplicated recovery.     

Pharmacological stress echocardiography in the diagnosis of coronary artery disease and myocardial ischaemia: a comparison between dobutamine and dipyridamole.

The objective of this study was to relate regional wall motion abnormalities assessed by dobutamine and dipyridamole stress echocardiography to quantitative measurements of coronary artery stenoses in consecutive patients referred for coronary angiography, and to compare haemodynamic effects of and complications related to the two agents. Patients underwent stress echoes on separate days in random sequence and had coronary angiography within 3 days of stress echocardiography. Echocardiograms were assessed by two investigators unaware of the patients' coronary anatomy. Coronary angiograms were also assessed quantitatively using the computer-assisted Cardiovascular Angiography Analysis System. There were 46 consecutive patients referred for coronary angiography; 28 were using beta-antagonists. Main outcome measures were sensitivity and specificity for dobutamine and dipyridamole stress echocardiography for detection of coronary artery disease (wall motion abnormalities at rest or stress) and myocardial ischaemia (stress induced new wall motion abnormalities). Sensitivity for the detection of myocardial ischaemia was found to be 57% for dobutamine and 64% for dipyridamole. Specificities were 78% and 89% respectively. Sensitivities for detection of coronary artery disease (lesion > or = 50% diameter stenosis) was 79% for dobutamine and 82% for dipyridamole; specificities were 78% and 89% respectively. These differences between the two agents are not significant. There were no severe side effects with either agent. Mean heart rate rose significantly with both tests but was higher with dobutamine; mean systolic blood pressure rose with dobutamine and fell with dipyridamole. It was concluded that dobutamine and dipyridamole stress echocardiography have similar sensitivities and specificities for detection of myocardial ischaemia and coronary artery disease although the haemodynamic effects of the two agents are different. Both are free from serious complications.     

临床疑似TTP-HUS患者血浆置换治疗引起的并发症

由于采用血浆置换(PE)治疗血栓性血小板减少性紫癜溶血性尿毒综合征(TTP HUS)频率的增加,PE引起的并发症也成为制定治疗方案时需要考虑的因素。由于TTP HUS的诊断常常是不确定的,掌握PE治疗利弊之间的平衡已成为制定适当治疗方案的焦点。之前,我们于1996年～2002年间曾两次报道     

Differential regulation of the growth-associated proteins, GAP-43 and SCG-10, in response to unilateral cortical ablation in adult rats

Synapse replacement after brain injury has been widely documented by anatomical studies in various parts of both the developing and adult nervous system. However, the molecular events that define the specificity of the empirically derived rules of reactive synaptogenesis in different regions of the adult brain remain unclear. In this study we examined the differential regulation of the lesion-induced response of the two growth-associated proteins, superior cervical ganglia-10 and growth-associated protein-43, after unilateral cortex ablation, and determined a hierarchical order for the lesion response from remaining afferent projection neurons originating from the contralateral cortex, ipsilateral thalamus and substantia nigra. We report that in response to unilateral cortex ablation both messenger RNA, by northern blot, and protein, by estern blot, for superior cervical ganglia-10 but not growth-associated protein-43 was increased in the homologous area of the contralateral cortex but not the ipsilateral thalamus or substantia nigra. In addition, the specificity of the superior cervical ganglia-10 response, assessed by combined in situ hybridization and retrograde FluoroGold labeling of striatal afferent neurons, found that superior cervical ganglia-10 messenger RNA was increased prominently in layer V pyramidal neurons of the contralateral corticostriatal pathway but was unchanged in afferent projection neurons from the thalamus and substantia nigra. Furthermore, the increase in both superior cervical ganglia-10 messenger RNA and protein seen at three days postlesion in contralateral corticostriatal neurons coincides in time with the initiation of neurite outgrowth in the deafferented striatum by contralateral corticostriatal axons described in our previous ultrastructural study. However, if cortical input to the striatum was removed bilaterally the lesion-induced response for superior cervical ganglia-10 messenger RNA shifted secondarily to thalamostriatal neurons in the ipsilateral thalamus.

These data provide evidence that superior cervical ganglia-10 and growth-associated protein-43 are differentially regulated in neurons of the contralateral corticostriatal pathway in response to unilateral cortex ablation and suggests that superior cervical ganglia-10 plays a role in the regulation of neurite outgrowth in the adult striatum after brain injury. However, the specific role that superior cervical ganglia-10 may play in reactive synaptogenesis remains unclear. In addition, our data suggest that a hierarchical order exists for the reinnervation of deafferented striatal neurons after unilateral cortex ablation with preference given to homologous axons from the contralateral cortex.     

Piezoelectric sensor determination of arterial pulse wave velocity

Arterial pulse wave velocity (APWV) is a measure of the elasticity (or stiffness) of peripheral arterial blood vessels. The pulse referred to here will be the pressure pulse as opposed to the flow pulse measured by ultrasound Doppler. The pressure pulse velocity varies over the range from about 12 m s(-1) to 15 m s(-1) in stiff peripheral arteries, whereas in normal arteries it has a velocity in the range of 7 to 9 m s(-1). The aim of this project was the development of a fast and easy to use system for the determination of peripheral arterial pulse wave velocity. The principle of the PWV measurement is based on simultaneous measurement of two pulse waves at two different positions, such as the radial artery at the wrist and the brachial artery just above the elbow. By determining the pulse transit time between these points and the distance measured between the two locations, pulse wave velocity may then be calculated. The pressure pulse detection is done by using two piezoelectric sensors which generate a measurable voltage at the output contacts if they are mechanically deformed. The deformation produced voltage is first amplified and filtered and then digitalized with a data acquisition card. The analysis of the data obtained from the sensors includes a filtering process, the calculation of the PWV with three different methods--foot-to-foot, cross-correlation and peak-to-peak-and the determination of the arterial pulse rate. Extensive measurements with human test subjects were carried out to optimize the techniques of data acquisition and analysis. For example, it was found that the best procedure was to hold the sensors in place using elastic straps alone. The data analysis was upgraded with an additional software module, which deletes, in effect, outriders or invalid measurements. With the optimized system, a series involving eight test subjects ranging in age from 22 to 32 years was completed (all normotensive). The arterial pulse wave velocities determined covered a range from 6 m s(-1) to 12 m s(-1), with an average standard deviation of less than 2.5 m s(-1) for individual results. These are slightly higher, but close to published APWV data. The results showed that reproducible results can be obtained with the existing PWV acquirement and analysis system.     

Splenic salvage quantified by uptake of heat-damaged radiolabeled red blood cells. Experimental and clinical studies

We evaluated a noninvasive radionuclide technique to quantify splenic trapping function, which is a key step in the disposition of blood-borne particulates such as poorly opsonized encapsulated microorganisms implicated in hyposplenic fulminant sepsis. Using computerized external gamma imaging, the percentage of splenic uptake of heat-damaged radiolabeled red blood cells was determined in adult Sprague-Dawley rats with eutopic (partial splenectomy) or ectopic (single or multiple autotransplantation) remnants or whole spleens, and in 14 patients with either an intact spleen or splenic remnants after treatment for trauma or hypersplenism. The masses of both eutopic and ectopic remnants correlated directly with the percentage of heat-damaged red blood cell uptake, but the percentage of uptake per gram was higher in eutopic remnants, paralleling more vigorous compensatory growth. In patients, the percentage of heat-damaged red blood cell uptake by remnant spleens was similar to that seen in the rats and, in addition, was supernormal in those with congestive splenomegaly. This noninvasive technique both provides a vivid biplanar image and quantifies blood-borne particle trapping, which is a key splenic function. A heat-damaged red blood cell uptake of less than 15 percent after splenic salvage suggests marginal splenic performance and continued vulnerability to overwhelming sepsis.     

Abnormal expression of hepatoma specific gamma-glutamyl transferase and alteration of gamma-glutamyl transferase gene methylation status in patients with hepatocellular carcinoma

Abnormal expression of hepatoma specific gamma-glutamyl transferase and alteration of gamma-glutamyl transferase gene methylation status in patients with hepatocellular carcinoma@Jiang DR @Huang ZW @Lu JX @Tao QY @Yu JZ @Meng XY