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An atherosclerotic plaque requires a nutrient blood supply, which is predominantly derived from arterial vasa vasorum. A variety of factors (environmental and genetic) contribute to the initiation and growth of atherosclerosis within vessel walls. Chemotactic factors, such as tissue ischemic and hypoxic factors, stimulate the release of vascular endothelial growth factor (VEGF) proteins, resulting in vessel wall angiogenesis. These developments often precede the formation of the luminal plaque. In this report, we describe the use of contrast-enhanced carotid ultrasound (CECU) imaging for the detection and quantification of intra-plaque neovascularization. The efficacy of CECU was measured against the neovascular density observed within the tissue specimens obtained at the time of carotid endarterectomy surgery. The objective of this study was to provide a histologic correlation between CECU and carotid artery atherosclerotic plaque neovascularization. Fifteen patients with significant atherosclerotic carotid artery disease received a CECU examination prior to undergoing a carotid endarterectomy (CEA). Two patients received bilateral endarterectomies, resulting in a total of 17 cases. At the time of surgery, carotid plaque samples were surgically removed and stained with specific vascular markers (CD31, CD34, von Willebrand factor, and hemosiderin) designed to identify the presence and degree of neovascularization. The intra-plaque neovascularization recorded on preoperative CECU was correlated with the degree of neovascularization noted in the tissue specimens. The CECU neovascularization was correlated to CD31-stained tissue specimens. This correlation value was 0.68 using Spearman's rank method. When CECU results were correlated with the other histologic markers (CD34, von Willebrand factor, and hemosiderin), a correlation of 0.50 was obtained. In conclusion, contrast-enhanced carotid ultrasound correlated to the presence and degree of intra-plaque neovascularization as determined from histology specimens.

Diabetes mellitus and the metabolic syndrome (MS) are reaching epidemic proportions in the United States, and cardiovascular disease continues to be the leading cause of death among patients with diabetes. A range of noninvasive screening tools may help reduce the morbidity and mortality of patients with diabetes because of early detection of subclinical cardiovascular disease and active monitoring of the effectiveness of therapy. Surrogate markers of subclinical disease include conventional and contrast-enhanced ultrasound imaging of carotid artery intima-media thickness (c-IMT), 2-dimensional echocardiography, coronary artery calcium imaging, cardiac magnetic resonance imaging, ankle-brachial indices, and brachial artery reactivity testing. Because these noninvasive imaging tools are relatively comfortable and entail relatively low risk to the patient, they are ideal for initial screening and for the repeated imaging that is required for monitoring the effectiveness of therapy. Moreover, when used in large numbers of patients with diabetes, prediabetes, and the MS, these imaging tools may be useful in developing and validating thresholds for the use of lipid-lowering therapy as well as clear therapeutic goals for this population. In addition, contrast-enhanced c-IMT scans now produce real-time images of the vasa vasorum and neovascularization of atherosclerotic plaque, potentially causing a paradigm shift in our view of the genesis of atherosclerosis and affecting treatment options for all populations. Thus, surrogate markers may not only help improve individual patient outcomes, they also may help direct scarce medical resources to maximize medical benefits, improve overall medical care, and minimize costs and untoward side effects.

Noninvasive surrogate markers of atherosclerosis allow the physician to identify subclinical disease before the occurrence of adverse cardiovascular events, thereby limiting the need to perform invasive diagnostic procedures. Imaging modalities, such as carotid artery ultrasound, two-dimensional echocardiography, coronary artery calcium imaging, cardiac magnetic resonance imaging, ankle-brachial indices, brachial artery reactivity testing, and epicardial coronary flow reserve measurements, provide information that may improve the predictive value of a person's risk of developing clinically significant atherosclerotic disease. Newer imaging modalities have also emerged to bring insight into the pathophysiology and treatment of atherosclerosis.

Adults of the rain-pool dwelling midge Chironomus pulcher are sexually dimorphic with females larger than males. This difference is achieved by females remaining in the growing larval stage for longer. When food is scarce, as under crowded conditions, the average size of both sexes is reduced, but the difference between them is maintained. However, more females perish, presumably because they are unable to achieve a minimum female size. Under conditions of crowding, there is thus a switch in favour of males. Since crowding due to a diminishing habitat is a frequent event in rain-pools, males seem fitter than females in C. pulcher. This paradox is discussed.

The authors report a case of a 68-year-old Caucasian female with type 2 diabetes mellitus who experienced an acute exacerbation of her rosacea 2 weeks after self-initiating cinnamon oil pills to lower her blood sugar levels. Historically, cinnamon oil has been used for a variety of medicinal purposes, but recently the use of cinnamon oil in lowering blood glucose and cholesterol levels in patients with type 2 diabetes is being investigated and gaining popularity amongst the general population. The use of cinnamon has commonly produced cutaneous side effects of irritant or allergic contact dermatitis and been reported to have vasodilatory effects. Yet, there are no reports of cinnamon use triggering a rosacea exacerbation in the literature.

The Pictorella Mannikin Lonchura pectoralis, which drinks by swallowing, normally imbibes water more rapdly than the Gouldian Finch Erythrura gouldiae, which drinks by sucking. Consequently, L. pectoralis completes drinking bouts more rapidly than E. gouldiae in the wild and thereby reduces the time spent at the water's edge where birds are at high risk of attack from predators. The sucking technique in E. gouldiae is, however, more effective than swallowing in L. pectoralis when brds have to: (1) reach down to drink from water beneath their perching places; (2) drink from shallow water, and (3) drink from small droplets of water. It is suggested that these skills enable E. gouldiae, and other species which drink by sucking, to exploit inaccessible sources of water and they may therefore be important in enabling them to survive conditions of drought and invade arid regions.

1. Small males of all midge (Diptera: Chironomidae and Chaoboridae) species thus far examined (one chaoborid and six chironomids) are rare in mating swarms. They are found instead in vegetation adjacent to the swarm. 2. We show that it is here that females aggregate prior to embarking on mate acquisition flights. In the vegetation females appear to be accessible to males staying behind. 3. Such behaviour in small males may exploit the mate-attracting activities of large males in the swarm and may, at the same time, reduce competition and conserve energy. 4. The evolution and maintenance of these size-related types of mating behaviour are discussed.