Abstract
Background
Optical diagnosis of colonic polyps is poorly reproducible outside of high volume referral centers. The present study aimed to assess whether real-time artificial intelligence ...(AI)-assisted optical diagnosis is accurate enough to implement the leave-in-situ strategy for diminutive (≤ 5 mm) rectosigmoid polyps (DRSPs).
Methods
Consecutive colonoscopy outpatients with ≥ 1 DRSP were included. DRSPs were categorized as adenomas or nonadenomas by the endoscopists, who had differing expertise in optical diagnosis, with the assistance of a real-time AI system (CAD-EYE). The primary end point was ≥ 90 % negative predictive value (NPV) for adenomatous histology in high confidence AI-assisted optical diagnosis of DRSPs (Preservation and Incorporation of Valuable endoscopic Innovations PIVI-1 threshold), with histopathology as the reference standard. The agreement between optical- and histology-based post-polypectomy surveillance intervals (≥ 90 %; PIVI-2 threshold) was also calculated according to European Society of Gastrointestinal Endoscopy (ESGE) and United States Multi-Society Task Force (USMSTF) guidelines.
Results
Overall 596 DRSPs were retrieved for histology in 389 patients; an AI-assisted high confidence optical diagnosis was made in 92.3 %. The NPV of AI-assisted optical diagnosis for DRSPs (PIVI-1) was 91.0 % (95 %CI 87.1 %–93.9 %). The PIVI-2 threshold was met with 97.4 % (95 %CI 95.7 %–98.9 %) and 92.6 % (95 %CI 90.0 %–95.2 %) of patients according to ESGE and USMSTF, respectively. AI-assisted optical diagnosis accuracy was significantly lower for nonexperts (82.3 %, 95 %CI 76.4 %–87.3 %) than for experts (91.9 %, 95 %CI 88.5 %–94.5 %); however, nonexperts quickly approached the performance levels of experts over time.
Conclusion
AI-assisted optical diagnosis matches the required PIVI thresholds. This does not however offset the need for endoscopistsʼ high level confidence and expertise. The AI system seems to be useful, especially for nonexperts.
Abstract Background and study aims Artificial Intelligence (AI) systems could make the optical diagnosis (OD) of diminutive colorectal polyps (DCPs) more reliable and objective. This study was aimed ...at prospectively evaluating feasibility and diagnostic performance of AI-standalone and AI-assisted OD of DCPs in a real-life setting by using a white light-based system (GI Genius, Medtronic Co, Minneapolis, Minnesota, United States). Patients and methods Consecutive colonoscopy outpatients with at least one DCP were evaluated by 11 endoscopists (5 experts and 6 non-experts in OD). DCPs were classified in real time by AI (AI-standalone OD) and by the endoscopist with the assistance of AI (AI-assisted OD), with histopathology as the reference standard. Results Of the 480 DCPs, AI provided the outcome “adenoma” or “non-adenoma” in 81.4% (95% confidence interval CI: 77.5–84.6). Sensitivity, specificity, positive and negative predictive value, and accuracy of AI-standalone OD were 97.0% (95% CI 94.0–98.6), 38.1% (95% CI 28.9–48.1), 80.1% (95% CI 75.2–84.2), 83.3% (95% CI 69.2–92.0), and 80.5% (95% CI 68.7–82.8%), respectively. Compared with AI-standalone, the specificity of AI-assisted OD was significantly higher (58.9%, 95% CI 49.7–67.5) and a trend toward an increase was observed for other diagnostic performance measures. Overall accuracy and negative predictive value of AI-assisted OD for experts and non-experts were 85.8% (95% CI 80.0–90.4) vs. 80.1% (95% CI 73.6–85.6) and 89.1% (95% CI 75.6–95.9) vs. 80.0% (95% CI 63.9–90.4), respectively. Conclusions Standalone AI is able to provide an OD of adenoma/non-adenoma in more than 80% of DCPs, with a high sensitivity but low specificity. The human-machine interaction improved diagnostic performance, especially when experts were involved.
Adiponectin is an adipocyte-secreted protein that modulates insulin sensitivity and whose low circulating concentration is associated with insulin resistance. In the present study, we analysed the ...association between two single-nucleotide polymorphisms (SNPs) in the adiponectin gene and insulin resistance in 253 nondiabetic subjects. In addition, we investigated whether this association is modulated by body mass index (BMI) levels. The SNPs +45T>G and +276G>T in the human adiponectin gene were detected in real-time PCR with LightCycler. No association was found with the +45T>G SNP. The +276G>T SNP was associated with higher BMI (P<0.01), plasma insulin (P<0.02) and HOMA(IR) (P<0.02). To analyse the possible interaction between BMI and the adiponectin gene on insulin resistance, the study group was divided into two subgroups, according to the BMI below or above the median of 26.2 kg/m(2). In both subgroups, subjects carrying the +276G>T SNP had higher HOMA(IR); however, the difference was highly significant among leaner (P<0.001), but not among heavier individuals, indicating that BMI status and the adiponectin gene interact in modulating insulin resistance. Among individuals with BMI <26.2 kg/m(2), the relative risk of insulin resistance was 9.7 (CI: 1.32-87.7, P<0.035). In a subgroup of 67 subjects, carriers of the +276G>T SNP had significantly (P<0.05) lower mean serum adiponectin levels (25.7 ng/ml) compared to noncarriers (37.0 ng/ml), suggesting a possible influence of the +276G>T SNP on adiponectin levels. In summary, we observed an association between the +276G>T SNP in the adiponectin gene and insulin resistance. In particular, among leaner individuals, the adiponectin gene appears to determine an increased risk to develop insulin resistance.
The effects of dietary vitamin E supplementation on the susceptibility to lipid oxidation and colour of the Longissimus thoracis (LT) muscle aged in vacuum packaged conditions for 3 or 14 days were ...studied. For this purpose, Charolais cattle were fed on a diet providing daily 60 mg (control) or 5500 mg of vitamin E per animal (supplemented) for 30 and 60 days before slaughter. Dietary vitamin E supplementation increased the liver vitamin E content, but not in the LT muscle of treated animals. The vitamin supplementation for 30 and 60 days has shown non-consistent effects in reducing cholesterol oxidation products of vacuum-packed aged meat. However, the vitamin E supplementation for 60 days was effective on Lightness stability in LT muscle during vacuum-packed ageing. Overall, from the practical standpoint, this study suggests that supra-nutritional supplementation up to 60 days may not increase the vitamin E content of Charolais LT muscle giving little, if any, benefits on meat colour and cholesterol oxidation. However, the present study suggests that it would be interesting to determine in which extent specific oxy-sterols are related to the meat colour and whether colour parameters can be useful for predicting the formation of cholesterol oxidation products along the industrial meat production chain.
An Unexpected Cause of Chronic Diarrhea Spinzi, Giancarlo; Pugliese, Delia; Filippi, Emanuela
Gastroenterology (New York, N.Y. 1943),
2016, January 2016, 2016-Jan, 2016-01-00, 20160101, Letnik:
150, Številka:
1
Journal Article
Solitary fibrous tumors of the liver (SFTL) are rare neoplasms, whose identification and definition of malignant potential are challenging.
A 62-year-old patient underwent conventional imaging and ...CEUS to characterize an indeterminate liver lesion after other imaging techniques were inconclusive. In fact, all diagnostic techniques concluded that it was a partially fibrotic lesion, while CEUS determined its extra-hepatocellular origin and malignant potential, initially hypothesized to be a cholangiocarcinoma. Due to the possible risk of seeding following a biopsy procedure, the patient was a candidate for surgery. Subsequently, histopathological examination revealed SFTL.
CEUS confidently characterized the malignancy and hypothesized the origin of the liver lesion, thus aiding in treatment planning.
As shown by genomic studies, colorectal cancer (CRC) is a highly heterogeneous disease, where copy number alterations (CNAs) may greatly vary among different patients. To explore whether CNAs may be ...present also in histologically normal tissues from patients affected by CRC, we performed CGH + SNP Microarray on 15 paired tumoral and normal samples. Here, we report for the first time the occurrence of CNAs as a common feature of the histologically normal tissue from CRC patients, particularly CNAs affecting different oncogenes and tumor-suppressor genes, including some not previously reported in CRC and others known as being involved in tumor progression. Moreover, from the comparison of normal vs paired tumoral tissue, we were able to identify three groups: samples with an increased number of CNAs in tumoral vs normal tissue, samples with a similar number of CNAs in both tissues, and samples with a decrease of CNAs in tumoral vs normal tissue, which may be likely due to a selection of the cell population within the tumor. In conclusion, our approach allowed us to uncover for the first time an unexpected frequency of genetic alteration in normal tissue, suggesting that tumorigenic genetic lesions are already present in histologically normal colonic tissue and that the use in array comparative genomic hybridization (CGH) studies of normal samples as reference for the paired tumors can lead to misrepresented genomic data, which may be incomplete or limited, especially if used for the research of target molecules for personalized therapy and for the possible correlation with clinical outcome.
Among the possible candidate genes for atherosclerosis experimental data point towards the longevity gene p66Shc. The p66Shc gene determines an increase of intracellular reactive oxygen species ...(ROS), affecting the rate of oxidative damage to nucleic acids. Knock-out p66Shc-/- mice show reduction of systemic oxidative stress, as well as of plasma LDL oxidation, and reduced atherogenic lesions. Thus, p66Shc may play a pivotal role in controlling oxidative stress and vascular dysfunction in vivo.
We searched for sequence variations in the p66Shc specific region of the Shc gene and its upstream promoter by PCR-SSCP in a selected group of early onset coronary artery disease (CAD) subjects (n. 78, mean age 48.5 +/- 6 years) and in 93 long-living control subjects (mean age 89 +/- 6 years).
The analysis revealed two variant bands. Sequencing of these variants showed two SNPs: -354T>C in the regulatory region of p66Shc locus and 92C>T in the p66 specific region (CH2). Both these variants have never been described before. The first substitution partially modifies the binding consensus sequence of the Sp1 transcription factor, and was detected only in two heterozygous carriers (1 CAD subjects and 1 control subject). The 92C>T substitution in the CH2 region consists in an amino acid substitution at codon 31 (proline to leucine, P31L), and was detected in heterozygous status only in one CAD subject. No subjects homozygous for the two newly described SNPs were found.
Only two sequence variations in the p66Shc gene were observed in a total of 171 subjects, and only in heterozygotes. Our observations, in accordance to other studies, suggest that important variations in the p66Shc gene may be extremely rare and probably this gene is not involved in the genetic susceptibility to CAD.
Adiponectin, an adipocyte-derived protein, is an essential modulator of insulin sensitivity and several studies suggest an important role of adiponectin in the processes leading to atherosclerosis, ...thus indicating the adiponectin gene as a potential candidate for coronary artery disease (CAD). In the present study we have studied the association between two single nucleotide polymorphisms (SNPs) (+45T>G and +276 G>T) of the adiponectin gene and CAD, looking also into the possible influence of these SNPs on adiponectin plasma levels. The SNPs were analysed in a first cohort of 595 subjects, 325 with CAD and 270 matched controls. We observed a significant association (p<0.001) between the SNP +276G>T in the adiponectin gene and CAD. In multivariate analysis, carriers of the +276G>T SNP had an odds ratio (OR) for CAD of 4.99 (p<0.0007). A strong interaction between the +276G>T SNP and age was also present (OR, 1.03; p<0.0001). The increase in CAD risk was most evident among individuals with early-onset CAD (age <or=50 years), whereas in older CAD subjects other factors, and not the adiponectin SNP, were the major determinants. Furthermore, in CAD subjects with early-onset disease this SNP was also a significant determinant of lower levels of serum adiponectin levels. This association resulted independent from the other variables known to be associated with CAD in our population, including sex, body mass index, high-density lipoprotein and Homeostasis Model Assessment for insulin resistance. To confirm the results the +276G>T SNP was analysed in a second cohort of CAD and controls. The difference between CAD and controls in the +276G>T SNP frequencies showed a similar trend as before, although not significant. The combination of the two cohorts (1,046 subjects: 580 CAD and 466 controls) showed a statistically significant association, particularly in CAD subjects with early-onset of disease. In addition, we confirmed that in younger CAD subjects the SNP was a significant determinant of lower levels of adiponectin. In view of these results, it could be speculated that the adiponectin gene variant, or a mutation in linkage with it, determines lower adiponectin gene expression, causing in turn an increased risk to develop insulin resistance, atherosclerosis and cardiovascular disease. The significant association of the adiponectin gene in subjects with early-onset CAD also suggests that that genetic factors for late-onset diseases may exert a greater influence in younger persons, when other risk factors are not as prevalent as in older age groups.
PDF
