[Assessments of carotid adventitial remodeling in metabolic syndrome patients using high-frequency ultrasound]

OBJECTIVE

To evaluate the changes of carotid adventitial thickness (AT) and intima media thickness (IMT) and their relationship in metabolic syndrome (MS) patients using high-frequency ultrasound.

METHODS

The values of mean AT and mean IMT were measured and calculated for 161 MS patients and compared them with 94 age and gender-matched controls as determined by high-frequency ultrasound between 2009-2011. And 161 patients were divided further into 2 groups of MS with plaque (MS-P, n = 70) and MS without plaque (MS-NP, n = 91).

RESULTS

MS-P and MS-NP patients had significantly higher values of mean IMT and carotid artery wall thickness than controls and MS-P patients had significantly higher values of mean AT than controls ((0.77 ± 0.13) mm vs (0.66 ± 0.11) mm, P < 0.01). Moreover, MS-P patients had significantly higher values of mean IMT ((0.98 ± 0.20) mm vs (0.76 ± 0.10) mm, P < 0.01), mean AT ((0.77 ± 0.13) vs (0.69 ± 0.13) mm, P < 0.01) and carotid artery wall thickness ((1.61 ± 0.16)mm vs (1.42 ± 0.09) mm, P = 0.002) than MS-NP patients. And mean AT was positively correlated with mean IMT in controls,MS-P and MS-NP patients (r = 0.603, P < 0.01, r = 0.325, P = 0.005 and r = 0.344, P = 0.004 separately).

CONCLUSION

For IMT and AT in MS patients with and without plaques, adventitia participates in vascular remodeling and may be distinguished by high-frequency ultrasound.

High spatial resolution MRI of cystic adventitial disease of the iliofemoral vein communicating with the hip joint

Venous cystic adventitial disease (CAD) is an extremely rare entity, and so far less than 20 cases have been described in the literature. Herein, we describe the imaging findings of CAD of iliofemoral vein in a 51-year-old woman who presented with leg swelling with special emphasis on high spatial resolution MRI, which demonstrated communication of the cyst with the hip joint. To our knowledge, this is the first description of high spatial resolution MRI findings in venous CAD supporting a new theory about the pathogenesis of venous CAD.

An abundant perivascular source of stem cells for bone tissue engineering

Adipose tissue is an ideal mesenchymal stem cell (MSC) source, as it is dispensable and accessible with minimal morbidity. However, the stromal vascular fraction (SVF) of adipose tissue is a heterogeneous cell population, which has disadvantages for tissue regeneration. In the present study, we prospectively purified human perivascular stem cells (PSCs) from n = 60 samples of human lipoaspirate and documented their frequency, viability, and variation with patient demographics. PSCs are a fluorescence-activated cell sorting-sorted population composed of pericytes (CD45-, CD146+, CD34-) and adventitial cells (CD45-, CD146-, CD34+), each of which we have previously reported to have properties of MSCs. Here, we found that PSCs make up, on average, 43.2% of SVF from human lipoaspirate (19.5% pericytes and 23.8% adventitial cells). These numbers were minimally changed by age, gender, or body mass index of the patient or by length of refrigerated storage time between liposuction and processing. In a previous publication, we observed that human PSCs (hPSCs) formed significantly more bone in vivo in comparison with unsorted human SVF (hSVF) in an intramuscular implantation model. We now extend this finding to a bone injury model, observing that purified hPSCs led to significantly greater healing of mouse critical-size calvarial defects than hSVF (60.9% healing as opposed to 15.4% healing at 2 weeks postoperative by microcomputed tomography analysis). These studies suggest that adipose-derived hPSCs are a new cell source for future efforts in skeletal regenerative medicine. Moreover, hPSCs are a stem cell-based therapeutic that is readily approvable by the U.S. Food and Drug Administration, with potentially increased safety, purity, identity, potency, and efficacy.

Computer vision analysis of collagen fiber bundles in the adventitia of human blood vessels

Numerical simulations, which are based on reliable biomechanical models of blood vessels, can help to get a better understanding of cardiovascular diseases such as atherosclerosis, and can be used to develop optimal medical treatment strategies.The adventitia is the outer most layer of blood vessels and its mechanical properties are essentially determined by the three-dimensional, structural arrangement of collagen fibre bundles embedded in the tissue. Global information such as the orientation statistics of the fibre bundles as well as detailed information as the crimp of the single fibres within the bundles is of particular interest in biomechanical modeling.In order to obtain a sufficiently large amount of data for biomechanical modeling, a fully automatic method for the structural analysis of the soft tissue is required. In this contribution we present methods based on computer vision to fulfill this task. We start by discussing proper tissue preparation and imaging techniques that have to be used to obtain data, which reliably represents the real three-dimensional tissue structure. The next step is concerned with algorithms that robustly segment the collagen fibre bundles and cope with various kinds of artifacts. Novel segmentation techniques for robust segmentation of individual fibril bundles and methods for estimation of their parameters, such as location, shape, mean fibril orientation, crimp of fibrils, etc, is discussed. The proposed algorithms are based on novel perceptual grouping methods operating on the extracted orientation data of fibrils.Finally, we demonstrate the results obtained by our fully automatic method on real data. In addition, for a more quantitative assessment, we introduce a generative structural model that enables the synthesis of three-dimensional fibre bundles with well-defined characteristics.

Congenital Saccular Aneurysms of the Aortic Ring

Congenital saccular aneurysms arising in the area of the aortic ring are not common. They may be located deep in the aortic sinus, at the commissure of two adjacent cusps, or in the area involving the membranous portion of the interventricular septum. They may be found at any age. This report concerns a child 2 years of age with a relatively large saccular aneurysm of the aortic ring just at the site of the commissure between the right and noncoronary cusps of the aortic valve. Terminally, this anomaly was complicated by infection leading to vegetative and ulcerative endocarditis. Death was sudden and was apparently directly related to the complications of the deformity.

Cellular Infiltration of the Human Arterial Adventitia Associated with Atheromatous Plaques

Homogeneous collections of cells resembling small lymphocytes have been found in the adventitia of atheromatous arteries, and the prevalence and degree of cellular infiltration have been shown to correlate closely with the severity of the plaques. The cells are found in the aorta, coronary, iliac, and carotid arteries; but in the carotid arteries the infiltration is less marked. Arterial blocks containing recent thrombus show more cellular infiltration than blocks without thrombus and with recanalizing thrombus.

The location and significance of the adventitial cellular infiltration is unknown, but it may play a part in the etiology or pathogenesis of arterial plaques.

THE ESTIMATION OF FIBROUS CONNECTIVE TISSUE IN LIVER BY A CHEMICAL METHOD

The chemical determination of hydroxyproline has been studied and a modification of the method of Neuman and Logan has been applied to hepatic tissue. The content of hydroxyproline in the livers of rats that had been fed experimental diets has been found to correlate well with the amounts of fibrous connective tissue (structural reticulin plus newly formed collagen) as estimated histologically.