Analysis of cell death and vertebral end plate bone mineral density in the annulus of the aging sand rat.

BACKGROUND CONTEXT: The relationship between disc degeneration and end plate sclerosis is poorly understood. The sand rat is an excellent, economical small-animal model in which disc degeneration is age related, spontaneous, reliable, and well characterized. This model is used here to evaluate disc degeneration, disc cell viability, and vertebral end plate bone mineral density (BMD) in lumbar sites. PURPOSE: To determine the proportion of live and dead cells and end plate bone mineral density in the aging sand rat annulus. STUDY DESIGN: Young and old sand rats were used in work approved by the Institutional Animal Care and Use Committee. Outcome measures were the percentage of live/dead annulus cells in the disc and the BMD of cranial and caudal end plates of lumbar vertebrae. METHODS: Bone densitometry was used to obtain endplate BMD on lumbar spines of 16 young sand rats aged 2 to 6 months and 26 older animals aged 22 to 46 months. X-ray films were analyzed for wedging, end plate calcification, and disc-space narrowing. Additional discs were also harvested and incubated with fluorochromes, and the percentage of live or dead cells were determined for the outer, inner annulus, and entire annulus. RESULTS: Radiographically old animals had significantly greater incidence of lumbar wedging (p<0.004) and a significantly greater incidence of end plate calcification and disc-space narrowing (p<0.01). In the live-dead study, the mean percentage of dead annulus cells for the three age groups were significantly different for the outer annulus (p<0.001), inner annulus (p=0.005), and total annulus (p<0.0001). The percentages of dead cells for the entire annulus were 46.14%+/-7.99% (age 2-6 months), 48.13%+/-17.32% (age, 13-19 months), and 76.80%+/-7.27% (age 26-38 months). The percentage of dead disc cells correlated significantly with age for outer annulus, inner annulus, and total annulus (p<0.006). The percentage of dead cells in the entire annulus and the inner annulus correlated significantly with end plate BMD (p<0.02). CONCLUSIONS: Data are novel and show that in very aged sand rats, end plate BMD is significantly greater than that of young animals. Live/dead cell analyses showed increasing cell death in both outer and inner annulus, which correlated significantly with age and with end plate BMD.     

Neurovascular injuries in acetabular reconstruction cage surgery: an anatomical study

Acetabular reconstruction cages are indicated for severe combined segmental and cavitary acetabular bone defects. The purpose of this study was to evaluate the implications of screw placement and drill plunge and the potential insult to anatomical structures when implanting acetabular reconstruction cages. A segmental cavitary defect was reamed into the acetabulum and a cage was implanted in each of the 10 hemipelvises. The relative course of the superior gluteal neurovascular bundle was mapped to assess dissection intervals. When cage screws were placed at least 15 mm longer than needed, 13% and 20% of screws of the superior flange and anterior rim hit the femoral nerve, respectively, and approximately 60% of the screws placed in the posterior rim endangered the obturator nerve. A "safe zone" for screw size may be a 15- and 25-mm screw for the superior flange and posterior rim, respectively.     

Effects of gonadal steroid withdrawal on serum phosphate and FGF-23 levels in men

INTRODUCTION: Fibroblast growth factor (FGF-23) is a novel phosphaturic factor. Current data suggest that serum phosphate, dietary phosphate and 1,25 dihydroxyvitamin D regulate circulating FGF-23 levels in vivo. We examined if hypogonadism-induced increases in serum phosphate are associated with increases in circulating FGF-23 in healthy men in the absence of dietary manipulation. MATERIALS AND METHODS: 25 healthy men were administered goserelin acetate (GnRH analog) 3.6 mg subcutaneously every 4 weeks for 12 weeks to induce acute testosterone and estrogen deficiency. Subjects consumed an ad libitum diet. Morning fasting blood and urine samples were collected to measure serum phosphate, serum intact FGF-23, PTH, and the maximum tubular reabsorption of phosphate (T(m)P/GFR) at baseline, weeks 4 and 12. The changes in serum FGF-23 and phosphate at weeks 4 and 12 were compared to baseline using paired t-tests. RESULTS: Goserelin therapy decreased mean serum testosterone levels from 543+/-160 ng/dL to 33+/-15 ng/dL at week 4 (p<0.001), and to 20+/-10 ng/dL at week 12 (p<0.001). Serum phosphate increased significantly from 3.4+/-0.6 mg/dL to 3.9+/-0.4 mg/dL at week 4 (p=0.002), and to 4.3+/-0.4 mg/dL at week 12 (p<0.001). T(m)P/GFR increased significantly from 3.2+/-0.6 mg/dL to 3.6+/-0.5 mg/dL at week 4 (p<0.004), and to 4.1+/-0.6 mg/dL at week 12 (p<0.001). FGF-23 levels, however, did not change during the 12-week study. CONCLUSIONS: Gonadal steroid deprivation increased serum phosphate levels in men but did not affect serum FGF-23 concentrations. The absence of any change in circulating FGF-23 suggests that supraphysiologic levels of serum phosphate may be required to stimulate circulating FGF-23 or that FGF-23 production is primarily sensitive to changes in dietary phosphate or 1,25 dihydroxyvitamin D within this physiologic serum phosphate range.     

New contribution to the study of ventricular remodeling and valve rings in dilated cardiomyopathy: anatomical and histological evaluation

Introduction

Idiopathic dilated cardiomyopathy causes great impact but many aspects of its pathophysiology remain unknown.

Objective

To evaluate anatomical and histological aspects of hearts with idiopathic dilated cardiomyopathy and compare them to a control group, evaluating the behavior of the perimeters of the atrioventricular rings and ventricles and to compare the percentage of collagen and elastic fibers of the atrioventricular rings.

Methods

Thirteen hearts with cardiomyopathy and 13 normal hearts were analysed. They were dissected keeping the ventricular mass and atrioventricular rings, with lamination of segments 20%, 50% and 80% of the distance between the atrioventricular groove and the ventricular apex. The sections were subjected to photo scanning, with measurement of perimeters. The atrioventricular rings were dissected and measured digitally to evaluate their perimeters, later being sent to the pathology laboratory, and stained by hematoxylin-eosin, picrosirius and oxidized resorcin fuccin.

Results

Regarding to ventricles, dilation occurs in all segments in the pathological group, and the right atrioventricular ring measurement was higher in idiopathic dilated cardiomyopathy group, with no difference in the left side. With respect to collagen, both sides had lower percentage of fibers in the pathological group. With respect to the elastic fibers, there was no difference between the groups.

Conclusion

There is a change in ventricular geometry in cardiomyopathy group. The left atrioventricular ring does not dilate, in spite of the fact that in both ventricles there is lowering of collagen.     

Liver Transplantation Outcome in Patients With Angiographically Proven Coronary Artery Disease: A Multi‐Institutional Study

Over the last decade the age of liver transplant (LT) recipients and the likelihood of coronary artery disease (CAD) in this population have increased. There are no multicenter studies that have examined the impact of CAD on LT outcomes. In this historical cohort study, we identified adult LT recipients who underwent angiography prior to transplantation at seven institutions over a 12‐year period. For each patient we recorded demographic data, recipient and donor risk factors, duration of follow‐up, the presence of angiographically proven obstructive CAD (≥50% stenosis) and post‐LT survival. Obstructive CAD was present in 151 of 630 patients, the CAD(+) group. Nonobstructive CAD was found in 479 patients, the CAD(?) group. Patient survival was similar for the CAD(+) group (adjusted HR 1.13, CI = [0.79, 1.62], p = 0.493) compared to the CAD(?) group. The CAD(+) patients were further stratified into severe (CADsev, >70% stenosis, n = 96), and moderate CAD (CADmod, 50–70% stenosis, n = 55) groups. Survival for the CADsev (adjusted HR = 1.26, CI = [0.83, 1.91], p = 0.277) and CADmod (adjusted HR = 0.93, CI = [0.52, 1.66], p = 0.797) groups were similar to the CAD(?) group. We conclude that when current CAD treatment strategies are employed prior to transplant, post‐LT survival is not significantly different between patients with and without obstructive CAD.     

Health related quality of life patterns in patients treated with interstitial prostate brachytherapy for localized prostate cancer--data from CaPSURE

PURPOSE: We measured the impact brachytherapy monotherapy (BMT) has on general and disease specific health related quality of life (HRQOL) compared to patients treated with radical prostatectomy (RP). MATERIALS AND METHODS: We studied 419 men with newly diagnosed prostate cancer who enrolled in CaPSURE (Cancer of the Prostate Strategic Urological Research Endeavor) data base whose primary treatment was brachytherapy monotherapy (92) or radical prostatectomy (327). The validated RAND 36-Item Health Survey and the UCLA Prostate Cancer Index were used to measure HRQOL before treatment and at 6-month intervals during the first 2 years after treatment. RESULTS: Patients treated with BMT or RP did not differ greatly in general HRQOL after treatment. Both treatment groups showed early functional impairment in most general domains with scores returning to or approaching baseline in most domains 18 to 24 months after treatment. Patients treated with BMT had significantly higher urinary function scores at 0 to 6 months after treatment (84.5, SD 18.7) than patients treated with RP (63.3, SD 26.6). Urinary bother scores at 0 to 6 months after treatment were not significantly different between patients treated with BMT (67.7, SD 31.2) and those treated with RP (67.4, SD 29.1). Both treatment groups had decreases in sexual function that did not return to pretreatment levels. CONCLUSIONS: Overall BMT and RP are well tolerated procedures that cause mild changes in general HRQOL. Disease specific HRQOL patterns are different in patients treated with BMT or RP. Baseline and serial HRQOL measurements after treatment can provide valuable information regarding expected quality of life outcome after treatment for localized prostate cancer.     

Effects of PEEP on residual vascularization in oesophageal substitution gastroplasty by surface oximetry-capnometry and photoplethysmography: an experimental study

OBJECTIVE: To evaluate the effects of positive end-expiratory pressure (PEEP) on residual vascularization in gastric tubes for oesophageal replacement. DESIGN: Experimental open study. MATERIALS: Eleven mongrel dogs. METHODS: Intestinal parietal blood flow was evaluated by photoplethysmography (PPG) and measurement of surface oxygen (PsO(2)) and carbon dioxide (PsCO(2)) tensions under basal conditions. After Akiyama's tubular gastroplasty, three levels of PEEP were administered. At each level, fluids were infused to counter the drop in cardiac output. PPG, surface gas tensions, arterial pressure, cardiac output and arterial blood gas tensions were monitored. Control sections of the bowel were also monitored by PPG. RESULTS: Cardiac output dropped for each level of PEEP and returned to basal levels on volume restabilization and on removal of PEEP. Central venous pressure and pulmonary arterial and capillary pressures increased for each level of PEEP and only returned to basal levels on removal of PEEP. PsO(2) values dropped for each level of PEEP and returned to basal levels on volume restabilization and on removal of PEEP. PsCO(2) levels rose, and PPG wave amplitude dropped, for each level of PEEP; these two variables only returned to basal levels on removal of PEEP. PPG values for the control sections reflected those of the anastomotic area. CONCLUSIONS: PEEP affects surface oxygen values at the level of the gastroplasty by means of its effect on cardiac output. PEEP also creates a venous return compromise and PPG wave amplitude and surface carbon dioxide values are related to this compromise. All three variables could be significant in anastomotic wound healing.