Computed tomography colonography: feasibility of computer-aided polyp detection in a "first reader" paradigm

OBJECTIVE:: To determine the feasibility of a computer-aided detection (CAD) algorithm as the "first reader" in computed tomography colonography (CTC). METHODS:: In phase 1 of a 2-part blind trial, we measured the performance of 3 radiologists reading 41 CTC studies without CAD. In phase 2, readers interpreted the same cases using a CAD list of 30 potential polyps. RESULTS:: Unassisted readers detected, on average, 63% of polyps > or =10 mm in diameter. Using CAD, the sensitivity was 74% (not statistically different). Per-patient analysis showed a trend toward increased sensitivity for polyps > or =10 mm in diameter, from 73% to 90% with CAD (not significant) without decreasing specificity. Computer-aided detection significantly decreased interobserver variability (P = 0.017). Average time to detection of the first polyp decreased significantly with CAD, whereas total reading case reading time was unchanged. CONCLUSION:: Computer-aided detection as a first reader in CTC was associated with similar per-polyp and per-patient detection sensitivity to unassisted reading. Computer-aided detection decreased interobserver variability and reduced the time required to detect the first polyp.     

Dose-responsiveness of electrophysiologic change in a new model of acute carpal tunnel syndrome

This study was done to determine the dose-responsiveness during the development of acute pressure-induced median neuropathy in rabbits and to develop a new animal model of acute carpal tunnel syndrome. Twenty-three rabbits were used. Carpal tunnel syndrome was induced by infusing a controlled saline solution into the carpal tunnel of rabbits using a 21-gauge needle under general anesthesia to elevate the carpal tunnel pressure. The changes in the amplitude and latency of the compound muscle action potential obtained by abductor pollicis recording were observed after a complete conduction block, and after the release of pressure at various pressure levels. Pressures greater than 30 mm Hg applied to the carpal tunnel caused a remarkable electrophysiologic change. A higher pressure level resulted in a shorter time required for a complete conduction block and also for recovery after the release of pressure. Complete conduction block occurred between 40 and 50 minutes at a pressure of 100 mm Hg. The degree of recovery after a conduction block was related inversely to the pressure-time integrals. Our animal model reflects the pathophysiology of acute carpal tunnel syndrome and shows a regular dose-responsiveness during the development of acute pressure-induced neuropathy.     

Targeting of<Emphasis Type="Italic"> lacZ</Emphasis> reporter gene expression with radioiodine-labelled phenylethyl-β-<Emphasis Type="SmallCaps">d</Emphasis>-thiogalactopyranoside

There has recently been increasing interest in the development of radioprobes that specifically target proteins transcribed from expression of reporter genes of interest. The purpose of this study was to develop a radioprobe that targets one of the most widely used reporter genes, the bacterial lacZ gene. We synthesised and purified radioiodine-labelled phenylethyl--d-thiogalactopyranoside (PETG), a competitive inhibitor specific against Escherichia coli -galactosidase. We showed that [¹²⁵I]iodo-PETG specifically binds to -galactosidase as verified by column chromatography and polyacrylamide gel electrophoresis after incubation of radiotracer with the protein. We also showed through enzyme kinetic studies that iodo-PETG retains inhibitory action against -galactosidase activity. COS-7 cells infected with a recombinant adenovirus expressing the lacZ gene had viral titre-dependent enhancements in [¹²⁵I]iodo-PETG uptake (r²=0.897; P=0.001), which reached up to 642.5%±16.7% of control levels (P<0.00001). Moreover, the level of uptake was highly correlated to luminescent measurements of -galactosidase activity (r²=0.878; P<0.0001). These results confirm that radioiodine-labelled PETG specifically targets -galactosidase and that its uptake rates faithfully reflect levels of expression of the lacZ reporter gene. Further investigations were performed in nude mice bearing human neuroblastoma tumours transferred with the lacZ gene. Compared with control tumours, lacZ-expressing tumours were slightly better visualised on [¹²³I]iodo-PETG images and had a modest increase in tumour to muscle count ratio (2.6±0.2 vs 1.9±0.1, P<0.05). The present results provide proof-of-principle for the potential of radiolabelled inhibitors as promising radiotracers to monitor lacZ gene expression levels. Future modifications to improve cell permeability should enhance in vivo contrast levels and may allow the use of radiolabelled -galactosidase inhibitors for non-invasive monitoring of lacZ gene expression.This work was presented in part at the 49th Annual Meeting of the Society of Nuclear Medicine, LA, USA, June 15–19, 2002.     

Amylase level after pancreaticoduodenectomy in predicting postoperative pancreatic fistula

BackgroundIt is new clinical interest higher serum amylase level with pancreatitis after pancreaticoduodenectomy (PD) correlates with postoperative pancreatic fistula (POPF). Nevertheless, its evidence and study were scarce. We aimed to investigate correlation of serum amylase level immediate after PD and POPF occurrence.MethodsOf 163 patients who underwent PD at between January 2009 and December 2019, retrospective analysis was conducted to identify risk factors including serum amylase level immediate after PD for POPF occurrence.ResultsOverall incidence of POPF (25/163) was 15.3%. The patients occurred a POPF had significantly higher level of serum amylase on POD0 compared to in whom without a POPF (414 vs 253, p < 0.001). In univariate analysis, ASA classification, post pancreatectomy acute pancreatitis (POAP, serum amylase on POD0 >285IU/L) and Fistula Risk Grade were correlated with POPF occurrence. In multivariable analysis, Fistula risk grade and POAP were significantly associated with developing POPF.ConclusionIn patients with higher serum amylase (>285IU/L) on POD0 with higher fistula risk grade, comprehensive management to achieve mitigation of POPF is important.     

Serum cystatin C for estimation of residual renal function in children on peritoneal dialysis

Residual renal function (RRF) is an important parameter in the management of patients on chronic dialysis. The aim of this cross-sectional study was to determine the efficacy of serum cystatin C (CysC) for RRF estimation in 20 children (16 boys, 4 girls; median age 13.4 years) undergoing peritoneal dialysis (PD). For studies of correlation with serum CysC, the average of creatinine clearance rate (C_cr) and urea clearance rate (C_urea), Kt/V_urea, and weekly C_cr were evaluated as parameters reflecting RRF. The serum CysC level was found to be negatively correlated with urine volume (r = −0.717, P < 0.001), average of C_cr and C_urea(r = −0.851, P < 0.001), total and renal weekly C_cr (r = −0.795, P < 0.001; r = −0.845, P < 0.001, respectively), and renal Kt/V_urea (r = −0.793, P < 0.001) and positively correlated with peritoneal weekly C_cr (r = 0.738, P < 0.001) and peritoneal Kt/V_urea (r = 0.785, P < 0.001). There was no significant association with total Kt/V_urea (r = −0.335, P = 0.148). In non-anuric group of patients, serum CysC had no link to peritoneal Kt/V_urea (r = 0.573, P = 0.066), but was negatively correlated with renal Kt/V_urea (r = −0.609, P = 0.047). In the multiple regression analysis, renal Kt/V_urea significantly contributed to log CysC concentration rather than peritoneal Kt/V_urea. The results of this study suggest that serum CysC could be an appropriate marker for RRF, independent of total and peritoneal Kt/V_urea.     

Protein Induced by Vitamin K Antagonist-II (PIVKA-II) Is a Reliable Prognostic Factor in Small Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) <2 cm in diameter has a favorable prognosis. Therefore surgical resection of small HCC is associated with good outcomes. However, the predisposing factors of prognosis following resection of HCC remain ill-defined. The aims of the present study were to identify the clinicopathologic characteristics and outcomes of patients with small HCC and analyze the predisposing factors for tumor recurrence after surgery.

Methods

We retrospectively reviewed 180 patients with small HCC who underwent hepatectomy between 2006 and 2010. Independent predictors of tumor recurrence were identified with Cox regression analysis.

Results

The 1-year, 3-year, and 5-year disease-free survival rates and overall survival rates were 83.7, 68.0, 65.3, and 98.9, 96.5, 92.7 %, respectively. Multivariate analysis reported that protein induced by the vitamin K antagonist-II (PIVKA-II) ≥200 mAU/mL, alkaline phosphatase (ALP) ≥80 IU/mL, and microvascular invasion were important predisposing factors for tumor recurrence. Elevated serum PIVKA-II level was associated with microvascular invasion in small HCC, which was a powerful predisposing factor.

Conclusions

Although small HCC is generally associated with a good prognosis, serum PIVKA-II level ≥200 mAU/mL, ALP ≥ 80 IU/L, and microvascular invasion were predisposing factors for tumor recurrence. These factors can be used to stratify patients with respect to recurrence after resection. Elevated PIVKA-II was closely associated with microvascular invasion in small HCC. These data emphasize the importance of PIVKA-II in small HCC.     

Calcium supplement intake and risk of cardiovascular disease in women

Summary

Some recent reports suggest that calcium supplement use may increase risk of cardiovascular disease. In a prospective cohort study of 74,245 women in the Nurses' Health Study with 24 years of follow-up, we found no independent associations between supplemental calcium intake and risk of incident coronary heart disease (CHD) and stroke.

Introduction

Some recent reports suggest that calcium supplements may increase cardiovascular disease (CVD) risk. The objective was to examine the independent associations between calcium supplement use and risk of CVD.

Methods

We conducted a prospective cohort study of supplemental calcium use and incident CVD in 74,245 women in the Nurses' Health Study (1984–2008) free of CVD and cancer at baseline. Calcium supplement intake was assessed every 4 years. Outcomes were incident CHD (nonfatal or fatal MI) and stroke (ischemic or hemorrhagic), confirmed by medical record review.

Results

During 24 years of follow-up, 4,565 cardiovascular events occurred (2,709 CHD and 1,856 strokes). At baseline, women who took calcium supplements had higher levels of physical activity, smoked less, and had lower trans fat intake compared with those who did not take calcium supplements. After multivariable adjustment for age, body mass index, dietary calcium, vitamin D intake, and other CVD risk factors, the relative risk of CVD for women taking >1,000 mg/day of calcium supplements compared with none was 0.82 (95 % confidence interval [CI] 0.74 to 0.92; p for trend <0.001). For women taking >1,000 mg/day of calcium supplements compared with none, the multivariable-adjusted relative risk for CHD was 0.71 (0.61 to 0.83; p for trend?<?0.001) and for stroke was 1.03 (0.87 to 1.21; p for trend?=?0.61). The relative risks were similar in analyses limited to non-smokers, women without hypertension, and women who had regular physical exams.

Conclusions

Our findings do not support the hypothesis that calcium supplement intake increases CVD risk in women.     

Reported alcohol consumption and cognitive decline: The northern Manhattan study

BACKGROUND: Moderate alcohol intake may slow cognitive decline, and both vascular and neurodegenerative mechanisms have been implicated. METHODS: We examined reported alcohol intake and cognitive decline in a community-based cohort of Hispanic, black and white individuals (n = 1,428). The role of the apolipoprotein E epsilon4 (APOE4) allele as a modifier was also studied. RESULTS AND CONCLUSIONS: Reported drinking was as follows: 300 participants (21%) were 'never' drinkers, 622 (44%) 'past' drinkers, 145 (10%) reported taking less than 1 drink weekly, 330 (23%) 1 drink weekly up to 2 daily and 31 (2%) more than 2 drinks daily. A positive relationship was seen between reported alcohol intake and cognition. Drinking less than 1 drink a week (p = 0.09), between 1 drink weekly up to 2 drinks daily (p = 0.001) and more than 2 drinks daily (p = 0.003) were associated with less cognitive decline on the modified Telephone Interview for Cognitive Status compared to never drinkers. This dose-response relationship was not modified by the presence of an APOE4 allele in a subsample.     

Gender differences in self-report of recovery after stroke: the Northern Manhattan Study

We compared subjective responses to simple questions after stroke with interviewer-assessed stroke outcome measures. Among those in the highest functional category, women were more likely to report incomplete recovery and greater need for help than men. Among these women, depressed mood was associated with a response of a need for help despite a good functional recovery. Self-reported responses in stroke outcome assessments require further validation by gender and may need to consider the confounding effects of depression.