Elastic stress distribution in cases of half-crowns use

Elastic stress distribution in abutment teeth, cement layer and abutment elements themselves was compared in cases of traditional half-crown and modified half-crown use. The results of the study let the authors come to the conclusion that when preparation rules were followed and exact adjustment the modified half-crown had advantages and could be used successfully.     

The effects of enfuvirtide therapy on body composition and metabolic parameters over 48 weeks in the TORO body imaging substudy*

Objective

The aim of the study was to compare the metabolic and morphological effects of enfuvirtide plus an optimized background (OB) regimen vs. OB alone (control group) in treatment‐experienced patients in the T‐20 vs. Optimized Regimen Only (TORO) studies.

Methods

Body composition and metabolic changes were investigated in patients over 48 weeks, based on fasting chemistries, body weight, and other anthropometric measurements. Dual‐energy X‐ray absorptiometry (DEXA) and computed tomography (CT) scans were performed in a patient subgroup (n=155) at baseline and at weeks 24 and 48.

Results

At week 48, mean changes from baseline were similar between treatment groups for glucose, insulin, C‐peptide, total cholesterol, low‐density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, high‐density lipoprotein (HDL) cholesterol and triglyceride levels. The enfuvirtide group experienced a significant increase in body weight [mean change from baseline +0.99 kg; 95% confidence interval (CI) +0.54, +1.44] and, in those who had body scans, there was a significant increase in truncal fat (by DEXA: median change +419.4 g; 95% CI+71.3, +767.5) and total fat [visceral adipose tissue (VAT)+subcutaneous adipose tissue (SAT) by single‐slice abdominal CT scan: median change +25.5 cm²; 95% CI+8.9, +42.0] over 48 weeks; significant increases in these parameters were not seen in the control group. There was no significant change in truncal:peripheral fat ratio in either the enfuvirtide or the control group.

Conclusion

The addition of enfuvirtide to an OB regimen does not appear to have unfavourable effects on fat distribution or metabolic parameters.     

Coexistence of superior mesenteric artery syndrome and nutcracker phenomenon

Superior mesenteric artery (SMA) syndrome is a rare cause of upper gastrointestinal obstruction. Nutcracker syndrome occurs as the result of external compression of the left renal vein. Although they share a similar pathophysiology, SMA and nutcracker syndrome occurring simultaneously is rare. In this case report, we discuss the pathophysiology and unique computed tomography findings in a 25-year-old female patient diagnosed with SMA syndrome who was also incidentally found to have a coexisting nutcracker phenomenon. Due to similar pathogenesis, radiologists should consider the possibility of coexistence of these rare syndromes in appropriate patients.     

Chronic mercury exposure at different concentrations produces opposed vascular responses in rat aorta

Mercury chloride exposure for 30 days decreases NO bioavailability and increases oxidative stress. However, the mechanisms underlying the effects of mercury on the cardiovascular system are not completely understood, and it is not known if they are dose‐dependent or if some concentrations have no harmful effects. Thus, we investigated the effects of chronic exposure to doses low (half) and high (2.5‐fold higher) than that needed to obtain 29 nmol/L of HgCl₂ on the vascular function. Three‐month‐old male Wistar rats received intramuscular (i.m.) HgCl₂ for 30 days and were divided in three groups: lower (Low Hg); higher (High Hg); and saline was used as the control. High Hg exposure increased the contractile response to phenylephrine (PHE) in aortic rings, but Low Hg reduced it. The hyporesponsiveness in the Low Hg rats was blunted by endothelial denudation and NOS inhibition with l ‐NAME (100 μmol/L). The phosphorylated‐eNOS/eNOS protein ratio increased in the aortas of Low Hg rats. In the High Hg group, endothelial denudation increased the PHE‐induced contractions, while l ‐NAME had no effects and indomethacin (10 μmol/L), losartan (10 μmol/L) and apocynin (30 μmol/L) reduced this response. In the High Hg group, protein levels of the NADPH oxidase subunit gp91phox and cyclooxygenase‐2 increased. Our results support previous suggestions that High Hg increases oxidative stress that might activate an inflammatory cascade and the renin‐angiotensin system. However, very low Hg concentrations below the level considered safe still reduced vascular reactivity, suggesting the need for special attention to continuous exposure as a putative cause of increased cardiovascular risk.     

Sensitivity and specificity of first screen mammography in the Canadian National Breast Screening Study: a preliminary report from five centers

Sensitivity and specificity of first screen mammography in a randomized screening trial at five centers are reported. A total of 23,101 women underwent mammography; in 139, breast cancer was detected at first screening; in 20, less than 12 months after first screening; and in 47, at second screening. All 206 cancer cases were histologically confirmed, and 174 were defined as being detectable at first screening. Average length of follow-up for all women was 3.2 years. Interpretations of first screen mammograms by the center radiologists were matched to known outcomes. Simultaneous blind review was performed by a single reference radiologist with mammograms from all 206 cancer cases and those of a random sample of 739 women not known to have breast cancer at 15 months or more after initial screening. Overall, the five screening centers achieved a sensitivity of 69% (range, 60%-78%), a specificity of 94% (range, 93%-96%), a positive predictive value of 8.6% (range, 3%-16%), and a negative predictive value of 99.7% (range, 99.6%-99.9%).