ABSTRACT
Type 2 diabetes (T2D) incidence in adolescents is rising and may interfere with peak bone mass acquisition. We tested the effects of early-onset T2D on bone mass, microarchitecture, and strength in the TALLYHO/JngJ mouse, which develops T2D by 8 weeks of age. We assessed metabolism and skeletal acquisition in male TALLYHO/JngJ and SWR/J controls (n = 8-10/group) from 4 weeks to 8 and 17 weeks of age. Tallyho mice were obese; had an approximately 2-fold higher leptin and percentage body fat; and had lower bone mineral density vs SWR at all time points (P < .03 for all). Tallyho had severe deficits in distal femur trabecular bone volume fraction (-54%), trabecular number (-27%), and connectivity density (-82%) (P < .01 for all). Bone formation was higher in Tallyho mice at 8 weeks but lower by 17 weeks of age vs SWR despite similar numbers of osteoblasts. Bone marrow adiposity was 7- to 50-fold higher in Tallyho vs SWR. In vitro, primary bone marrow stromal cell differentiation into osteoblast and adipocyte lineages was similar in SWR and Tallyho, suggesting skeletal deficits were not due to intrinsic defects in Tallyho bone-forming cells. These data suggest the Tallyho mouse might be a useful model to study the skeletal effects of adolescent T2D.
Subject(s)
Bone Development , Diabetes Mellitus, Type 2/physiopathology , Age Factors , Age of Onset , Animals , Bone Density/drug effects , Bone Density/genetics , Bone Development/drug effects , Bone Development/genetics , Cells, Cultured , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Type 2/genetics , Diet, High-Fat , Dietary Sucrose/pharmacology , Male , Mice , Mice, Mutant Strains , Mice, Obese , Osteogenesis/physiologyABSTRACT
INTRODUCTION: Stasis filling, defined as delayed, weak, and persistent opacification of proximal segments of the cerebral arteries, is frequently found in brain dead patients. This phenomenon causes a major problem in the development of reliable computed tomographic angiography (CTA) protocol in the diagnosis of brain death (BD). The aim of our study was to characterize stasis filling in the diagnosis of BD. To achieve this, we performed a dynamic evaluation of contrast enhancement of the cerebral and extracranial arteries in patients with BD and controls. METHODS: Study population included 30 BD patients, who showed stasis filling in computed tomographic perfusion (CTP) series. Thirty patients, after clipping of an intracranial aneurysm, constituted the control group. The study protocol consisted of CTA, CTP, and angiography. Time-density curves (TDCs) of cerebral and extracranial arteries were generated using 40-s series of CTP. RESULTS: Cerebral TDCs in BD patients represented flat curves in contrast to TDCs in controls, which formed steep and narrow Gaussian curves. We found longer time to peak enhancement in BD patients than in controls (32 vs. 21 s; p < 0.0001). In BD patients, peak enhancement in the cerebral arteries occurred with a median delay of 14.5 s to peak in extracranial arteries, while no delay was noted in controls (p < 0.0001). Cerebral arteries in BD patients showed lower peak enhancement than controls (34.5 vs. 81.5 HU; p < 0.0001). In all BD patients, CTP revealed zero values of cerebral blood flow and volume. Angiography showed stasis filling in 14 (46.7 %) and non-filling in 16 (53.3 %) cases. CONCLUSION: A confrontation of stasis filling with CTP results showed that stasis filling is not consistent with preserved cerebral perfusion, thus does not preclude diagnosis of BD.
Subject(s)
Brain Death , Cerebral Angiography/methods , Cerebral Arteries/diagnostic imaging , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young AdultABSTRACT
UNLABELLED: The aim of the study was estimation of some blood flow parameters in arteries of both forearms in patients with "sleeve" arterio-venous fistula (AVF) created for hemodialysis. From 1988 to 1996 145 radio-cephalic AVF's with "sleeve" anastomoses were created in our Department. Duplex-Scan examinations were performed in 30 patients aged from 22 to 68 years. There are 15 women and 15 men with primary AVF lasting over 12 months. The B&K Medical System 3535 with 7.5 MHz transducer was used for all measurements. Diameter of radial artery (TP) in forearms with AVF fistula was on average 4.7 mm, and in ulnar artery (TL) 2.6 mm. In forearms without AVF diameters were, respectively 2.4 mm and 2.3 mm. Volume flow in forearms with AVF was in TP 1056, and in TL 169 ml/min. In forearms without AVF these flows were 59 and 63 ml/mm, respectively. Resistance index in forearms with AVF was 0.29 in TR and 0.47 in TL, however in forearms without AVF 0.76 in both arteries. Pulsatility index on the side of AVF was 0.8 in TR and 1.8 in TL, however on the side without AVF 4.1 in both arteries. These differences were statistically significant. CONCLUSIONS: 1. In arteries of forearm with AVF diameter and volume blood flow increases, however resistance and pulsatility indices decreases. 2. Volume flow in ulnar artery in forearms with AVF is similar to flow in both arteries in forearm without AVF.
