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21.

Background

Validation of digital whole slide images is crucial to ensure that diagnostic performance is at least equivalent to that of glass slides and light microscopy. The College of American Pathologists Pathology and Laboratory Quality Center recently developed recommendations for internal digital pathology system validation. Following these guidelines we sought to validate the performance of a digital approach for routine diagnosis by using an iPad and digital control widescreen-assisted workstation through a pilot study.

Methods

From January 2014, 61 histopathological slides were scanned by ScanScope Digital Slides Scanner (Aperio, Vista, CA). Two independent pathologists performed diagnosis on virtual slides in front of a widescreen by using two computer devices (ImageScope viewing software) located to different Health Institutions (AOUI Verona) connected by local network and a remote image server using an iPad tablet (Aperio, Vista, CA), after uploading the Citrix receiver for iPad. Quality indicators related to image characters and work-flow of the e-health cockpit enterprise system were scored based on subjective (high vs poor) perception. The images were re-evaluated two weeks apart.

Results

The whole glass slides encountered 10 liver: hepatocarcinoma, 10 renal carcinoma, 10 gastric carcinoma and 10 prostate biopsies: adenocarcinoma, 5 excisional skin biopsies: melanoma, 5 lymph-nodes: lymphoma. 6 immuno- and 5 special stains were available for intra- and internet remote viewing. Scan times averaged two minutes and 54 seconds per slide (standard deviation 2 minutes 34 seconds). Megabytes ranged from 256 to 680 (mean 390) per slide storage. Reliance on glass slide, image quality (resolution and color fidelity), slide navigation time, simultaneous viewers in geographically remote locations were considered of high performance score. Side by side comparisons between diagnosis performed on tissue glass slides versus widescreen were excellent showing an almost perfect concordance (0.81, kappa index).

Conclusions

We validated our institutional digital pathology system for routine diagnostic facing with whole slide images in a cockpit enterprise digital system or iPad tablet. Computer widescreens are better for diagnosing scanned glass slide that iPad. For urgent requests, iPad may be used. Legal aspects have to be soon faced with to permit the clinical use of this technology in a manner that does not compromise patient care.
  相似文献   
22.
Aim Understanding the importance of ecological factors in the origin and maintenance of patterns of phenotypic variation among populations, in an explicit geographical context, is one of the main goals of human biology, ecology and evolutionary biology. Here we study the ecological factors responsible for craniofacial variation among human populations from South America. Location South America. Methods We studied a dataset of 718 males from 40 South American populations, coming from groups that inhabited different geographical and ecological regions. Cranial size and shape variation were studied using 30 cranial measurements. We first used spatial correlograms and interpolated maps to address spatial patterns. We then regressed the shape (principal component scores) and size variables against ecology (mean annual temperature and diet) using multiple and multivariate spatial regression. Finally, the expected magnitudes of shape and size divergence under the influence of genetic drift and mutations alone were evaluated using neutral expectation for the divergence rate. Results The spatial correlograms showed a cline affecting the entire South American distribution. Interpolated maps showed that size and allometric shape vary from south‐east to north‐west. Multiple and multivariate regression analyses suggested that diet has the largest and most significant effect on this pattern of size and allometric shape variation. Finally, the results of the divergence rate test suggested that random processes alone cannot account for the morphological divergence exhibited by cranial size and allometric shape scores among southernmost populations. Main conclusions Correlograms, spatial regression and divergence rate analyses showed that although local factors (neutral processes or local environmental conditions) are important to explain spatial interpopulation differentiation in cranial characteristics among these populations, there is significant correlation of cranial size and allometric shape variation with diet. Gene flow among human populations, or local environmental conditions, could explain spatial variation mainly at smaller spatial scales, whereas the large‐scale pattern of the South American dataset is mainly related to the high proportion of carbohydrates and low proportion of proteins consumed.  相似文献   
23.
The objective of this study was to investigate the influence of Spondias mombin (SM) supplementation on the cardiac remodelling process induced by exposure to tobacco smoke (ETS) in rats. Male Wistar rats were divided into 4 groups: group C (control, n = 20) comprised animals not exposed to cigarette smoke and received standard chow; group ETS (n = 20) comprised animals exposed to cigarette smoke and received standard chow; group ETS100 (n = 20) received standard chow supplemented with 100 mg/kg body weight/d of SM; and group ETS250 (n = 20) received standard chow supplemented with 250 mg/kg body weight/d of SM. The observation period was 2 months. The ETS animals had higher values of left cardiac chamber diameters and of left ventricular mass index. SM supplementation attenuated these changes. In addition, the myocyte cross‐sectional area (CSA) was lower in group C compared with the ETS groups; however, the ETS250 group had lower values of CSA compared with the ETS group. The ETS group also showed higher cardiac levels of lipid hydroperoxide (LH) compared with group C; and, groups ETS100 and ETS250 had lower concentrations of LH compared with the ETS group. Regarding energy metabolism, SM supplementation decreased glycolysis and increased the β‐oxidation and the oxidative phosphorylation. There were no differences in the expression of Nrf‐2, SIRT‐1, NF‐κB, interferon‐gamma and interleukin 10. In conclusion, our results suggest that ETS induced the cardiac remodelling process. In addition, SM supplementation attenuated this process, along with oxidative stress reduction and energy metabolism modulation.  相似文献   
24.
In this study the Authors verify the results of Picotamide on platelet aggregation in diabetic subjects. The results suggest that Picotamide has no influence on insulin or oral treatment of diabetic subjects. However, it is certain that platelet aggregation by ADP or collagen decreases due to the effect on thromboxane probably because of the limitation of platelet receptors.  相似文献   
25.
26.
The effect of prostaglandins on the in vivo induction of theta antigen in splenic spontaneous rosette-forming cells derived from adult thymectomized mice was studied. A long-acting synthetic analog of prostaglandin E2, di-M-PGE2, mimicked the effects of thymic hormone and was active when mice were treated with as little as 0.1 μg ip. In addition, indomethacin, a potent inhibitor of prostaglandin biosynthesis, was able to reverse the inductive effects of exogenous thymic hormone and inhibit the expression of theta antigen in normal mice, presumably by interfering with the effect of endogenous thymic factors. Finally, indomethacin also partially suppressed the stimulatory effects of exogenously administered di-M-PGE2, suggesting that this agent is effective, at least in part, because it stimulates endogenous prostaglandin biosynthesis. Possible mechanisms of action for the effects of prostaglandins are presented.  相似文献   
27.
The synthesis is described of a [D-Ala2]-deltorphin I peptoid analogue in which all amino acid residues have been substituted by the corresponding N-alkylglycine residues. The [D-Ala2]-deltorphin I retropeptoid was also prepared as well as [Ala1 ,D-Ala2]-deltorphin 1 and the corresponding peptoid. Structural investigations by FT-IR and fluorescence measurements were carried out on the synthetic analogues and on some [D-Ala2]-deltorphin 1 peptide-peptoid hybrids previously prepared. According to the fluorescence measurements the distance between the aromatic residues in the deltorphin I peptoid and retropeptoid is similar to that suggested for the delta- and micro-opioids, respectively. Measurements of CD in the presence of beta-cyclodextrin, and some preliminary pharmacological experiments were also performed. No dichroic bands are present in the spectrum of the [Ntyr1,D-Ala2]-deltorphin I, but an increasing dichroic effect appears in the spectra of both the deltorphin I peptoid and retropeptoid. Activity tests on isolated organ preparations showed that the modifications made produced a dramatic decrease in the agonistic activity of the synthetic derivatives.  相似文献   
28.
This work estimates the influence of the single twitch (ST) parameters changes on specific regions of the force-frequency relationship (FFR) in fatigued human tibialis anterior (TA). In 20 subjects (age 20-40) the TA underwent three stimulation phases: (a) five STs at 1 Hz followed by 5 s stimulation with increasing rate (1-50 Hz, to obtain FFR); (b) fatiguing stimulation (35 Hz for 40 s); (c) same as in "a". By the average STs (mean of the five responses) of a and c phases, the peak twitch (Pt) was calculated. Moreover, after ST normalization to Pt, the maximum contraction rate (MCR) and the maximum relaxation rate (MRR) were computed. By the FFR, normalized to the 50 Hz force, we first defined the threshold frequency (TF) when the force oscillation presented the same value in (a) and (c), and then the areas below the FFR in the 1 Hz-TF and in the TF-50 Hz ranges. RESULTS: In unfatigued and fatigued muscle Pt, and MRR changed from 6.12 +/- 3.08 to 3.27 +/- 1.16 N and from 0.87 +/- 0.13 to 0.65 +/- 0.09% Pt/ms, respectively. MCR did not change significantly. The 1 Hz-TF area ratio (c/a) was > 1 for muscles having fatigued Pt > 60% of its basal value. The TF-50 Hz area ratio (c/a) was mostly below 1. CONCLUSIONS: At fatigue, MRR reduction, leading to a better fusion of muscle mechanical output, is able to compensate, in the 1 Hz-TF frequency range, up to 40% Pt loss; beyond TF, the changes of FFR are related to the degree of force loss indicated by the fatigued Pt.  相似文献   
29.
In this paper we present a study on the intracellular localisation and the efficiency of cell photoinactivation of a series of derivatives of 5,10,15,20-tetrakis-(4-N-methylpyridyl)-porphine (C1), whose degree of lipophilicity was varied through replacement of one methyl group with an alkyl chain of various length. Human HT1080 fibrosarcoma cells exposed to the various C1 derivatives (0.25 microM) for 24 h and irradiated with increasing doses of red-light (0.45-27 J/cm2) were inactivated with different efficiencies. The efficiency of cell photoinactivation increased with the increasing length of the hydrocarbon tail and lipophilicity and correlated with the efficiency of the porphyrin accumulation into the cells. Despite the presence of positive charges, these porphyrins did localise rather selectively in lysosomes while mitochondrial localisation was not evident, as demonstrated by fluorescence microscopy studies. Studies on isolated mitochondria provided evidence that the porphyrin uptake and distribution in these organelles were not modulated by the transmembrane potential but were exclusively controlled by partitioning phenomena which might have prevented mitochondria localization in whole cells. Our findings demonstrated that these porphyrins entered the cells through the endocytotic pathway and were transported to lysosomes whose pH increased rapidly upon irradiation. Lysosomal damage did not cause any intracellular redistribution of the porphyrin and represented the primary event causing cell death, very likely via necrosis.  相似文献   
30.
Lung cancer encompasses a constellation of malignancies with no validated prognostic markers. p16Ink4A expression has been reported in different subtypes of lung cancers; however, its prognostic value is controversial. Here, we sought to investigate the clinical significance of p16Ink4A immunoexpression according to specific staining patterns and its operational implications. A total of 502 tumors, including 277 adenocarcinomas, 84 squamous cell carcinomas, 22 large cell carcinomas, 47 typical carcinoids, 12 atypical carcinoids, 28 large cell neuroendocrine carcinomas, and 32 small cell carcinomas were reviewed and subjected to immunohistochemical analysis for p16Ink4A and Ki67. The spectrum of p16Ink4A expression was annotated for each case as negative, sporadic, focal, or diffuse. Expression at immunohistochemical level showed intra-tumor homogeneity, regardless tumor histotype. Enrichments in cells expressing p16Ink4A were observed from lower- to higher-grade neuroendocrine malignancies, whereas a decrease was seen in poorly and undifferentiated non-neuroendocrine carcinomas. Tumor proliferation indices were higher in neuroendocrine tumors expressing p16Ink4A while non-neuroendocrine malignancies immunoreactive for p16Ink4A showed a decrease in Ki67-positive cells. Quantitative statistical analyses including each histotype and the p16Ink4A status confirmed the independent prognostic role of p16Ink4A expression, being a high-risk indicator in neuroendocrine tumors and a marker of good prognosis in non-neuroendocrine lung malignancies. In this study, we provide circumstantial evidence to suggest that the routinary assessment of p16Ink4A expression using a three-tiered scoring algorithm, even in a small biopsy, may constitute a reliable, reproducible, and cost-effective substrate for a more accurate risk stratification of each individual patient.  相似文献   
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