672 research outputs found
CT attenuation analysis of carotid intraplaque hemorrhage
Background and Purpose: Intraplaque hemorrhage is considered a leading parameter of carotid plaque vulnerability. Our purpose was to assess the CT characteristics of intraplaque hemorrhage with histopathologic correlation to identify features that allow for confirming or ruling out the intraplaque hemorrhage. MATERIALS AND METHODS: This retrospective study included 91 patients (67 men; median age, 657 years; age range, 41-83 years) who underwent CT angiography and carotid endarterectomy from March 2010 to May 2013. Histopathologic analysis was performed for the tissue characterization and identification of intraplaque hemorrhage. Two observers assessed the plaque's attenuation values by using an ROI (â€1 and â„2 mm2). Receiver operating characteristic curve, Mann-Whitney, and Wilcoxon analyses were performed. RESULTS: A total of 169 slices were assessed (59 intraplaque hemorrhage, 63 lipid-rich necrotic core, and 47 fibrous); the average values of the intraplaque hemorrhage, lipid-rich necrotic core, and fibrous tissue were 17.475 Hounsfield units (HU) and 18.407 HU, 39.476 HU and 48.048 HU, and 91.66 HU and 93.128 HU, respectively, before and after the administration of contrast medium. The Mann-Whitney test showed a statistically significant difference of HU values both in basal and after the administration of contrast material phase. Receiver operating characteristic analysis showed a statistical association between intraplaque hemorrhage and low HU values, and a threshold of 25 HU demonstrated the presence of intraplaque hemorrhage with a sensitivity and specificity of 93.22% and 92.73%, respectively. The Wilcoxon test showed that the attenuation of the plaque before and after administration of contrast material is different (intraplaque hemorrhage, lipid-rich necrotic core, and fibrous tissue had P values of .006, .0001, and .018, respectively). CONCLUSIONS: The results of this preliminary study suggest that CT can be used to identify the presence of intraplaque hemorrhage according to the attenuation. A threshold of 25 HU in the volume acquired after the administration of contrast medium is associated with an optimal sensitivity and specificity. Special care should be given to the correct identification of the ROI
correlation between fissured fibrous cap and contrast enhancement preliminary results with the use of cta and histologic validation
BACKGROUND AND PURPOSE: Previous studies demonstrated that carotid plaques analyzed by CTA can show contrast plaque enhancement. The purpose of this preliminary work was to evaluate the possible association between the fissured fibrous cap and contrast plaque enhancement. MATERIALS AND METHODS: Forty-seven consecutive (men = 25; average age = 66.8 ± 9 years) symptomatic patients studied by use of a multidetector row CT scanner were prospectively analyzed. CTA was performed before and after contrast and radiation doses were recorded; analysis of contrast plaque enhancement was performed. Patients underwent carotid endarterectomy en bloc; histologic sections were prepared and evaluated for fissured fibrous cap and microvessel attenuation. The Mann-Whitney test was performed to evaluate the differences between the 2 groups. A multiple logistic regression analysis was performed to assess the effect of fissured fibrous cap and microvessel attenuation on contrast plaque enhancement. Receiver operating characteristic curve and area under the curve were also calculated. RESULTS: Twelve patients had fissured fibrous cap. In 92% (11/12) of fissured fibrous capâpositive plaques, we found contrast plaque enhancement, whereas in 69% (24/35) of the plaques without fissured fibrous cap contrast plaque enhancement was found. The Mann-Whitney test showed a statistically significant difference between the contrast enhancement in plaques with fissured fibrous cap (Hounsfield units = 22.6) and without fissured fibrous cap (Hounsfield units = 12.9) ( P = .011). On the regression analysis, both fissured fibrous cap and neovascularization were associated with contrast plaque enhancement ( P = .0366 and P = .0001). The receiver operating characteristic curve confirmed an association between fissured fibrous cap and contrast plaque enhancement with an area under the curve of 0.749 ( P = .005). CONCLUSIONS: The presence of fissured fibrous cap is associated with contrast plaque enhancement. Histologic analysis showed that the presence of fissured fibrous cap is associated with a larger contrast plaque enhancement compared with the contrast plaque enhancement of plaques without fissured fibrous cap
Cytokeratin 20-positive hepatocellular carcinoma
The differential diagnosis between hepatocellular carcinoma (HCC), cholangiocarcinoma (CC) and metastatic colorectal adenocarcinoma (MCA) may be difficult when only based on morphology. For this purpose immunohistochemical analyses are often required, utilizing antibodies directed against CK8-18, Hep-Par1, glypican 3, CK7, CK19, CK20. Here we report a case of a 65-year-old man who presented with a clinical picture of decompensated cirrhosis. Ultrasonography revealed two nodular areas in the right liver lobe. Liver needle biopsy revealed micro-macronodular cirrhosis associated with HCC with trabecular and pseudoglandular patterns. Immunohistochemically, tumour cells were diffusely positive for CK8-18 and also diffusely immunostained by glypican 3 and Hep-Par1. Interestingly, a diffuse and strong staining for CK20 was detected in the vast majority of tumor cells, particularly in the areas showing a pseudo-glandular pattern. No immunostaining for CK7 and CK19 was found in the tumor cells. The tumor behaved aggressively, with a rapid diffusion to the whole liver. The patient died from the disease few months after presentation. These findings underline that the interpretation of the expression of CK20 alone in the differential diagnosis among HCC, CC and MCA should be done with caution because a diffuse immunoreactivity for CK20 alone may not rule out the diagnosis of HCC
HLA-G expression and role in advanced-stage classical Hodgkin lymphoma
Non-classical human leucocyte antigen (HLA)-G class I molecules have an important role in tumor immune escape mechanisms. We investigated HLA-G expression in lymphonode biopsies taken from 8 controls and 20 patients with advanced-stage classical Hodgkin lymphoma (cHL), in relationship to clinical outcomes and the HLA-G 14-basepair (14-bp) deletion-insertion (del-ins) polymorphism. Lymphnode tissue sections were stained using a specific murine monoclonal HLA-G antibody. HLA-G protein expression was higher in cHL patients than controls. In the group of PET-2 positive (positron emission tomography carried out after 2 cycles of standard chemotherapy) patients with a 2-year progression-free survival rate (PFS) of 40%, we observed high HLA-G protein expression within the tumor microenvironment with low expression on Hodgkin and Reed-Sternberg (HRS) cells. Conversely, PET-2 negative patients with a PFS of 86% had higher HLA-G protein expression levels on HRS cells compared to the microenvironment. Lower expression on HRS cells was significantly associated with the HLA-G 14-bp ins/ins genotype. These preliminary data suggest that the immunohistochemical pattern of HLA-G protein expression may represent a useful tool for a tailored therapy in patients with cHL, based on the modulation of HLA-G expression in relation to achievement of negative PET-
Plasma cells in the carotid plaque: occurrence and significance
OBJECTIVE: Atherosclerosis is one of the leading causes of disability and mortality worldwide. Inflammation, including monocytes, T and B cells, plays a key role in its pathogenesis. Our purpose was to evaluate plasma cellsâ presence in a large series of carotid artery plaques and the clinical association.
PATIENTS AND METHODS: Forty-eight consecutive patients treated with carotid endarterectomy were retrospectively analyzed to assess plasma cellsâ presence inside the plaque. A semiquantitative grading score was applied, ranging from absence, scattered, clusters of 5-10, and sheets of >10 plasma cells. Plasma cellâs location, as intraplaque, subendothelial or peri-adventitial, was also defined.
RESULTS: In 75% of plaques analyzed, plasma cells were detected: scattered in 63.9%, in clusters in 22.2%, and in sheets in 13.9% of cases. In all cases, plasma cells were observed only inside the plaque. In 13.9% and in 11.1% of cases, plasma cells showed, respectively, a concomitant subendothelial or peri-adventitial distribution. In 5.6% of plaques, there was a simultaneous distribution in subendothelial, peri-adventitial layer, and intraplaque. Association between the presence of symptoms and plasma cells infiltrate was found.
CONCLUSIONS: Our results suggest that plasma cells could be a key parameter linked to plaque instability. Some types of configurations are significantly associated with the occurrence of cerebrovascular symptoms
The construction of non-spherical models of quasi-relaxed stellar systems
Spherical models of collisionless but quasi-relaxed stellar systems have long
been studied as a natural framework for the description of globular clusters.
Here we consider the construction of self-consistent models under the same
physical conditions, but including explicitly the ingredients that lead to
departures from spherical symmetry. In particular, we focus on the effects of
the tidal field associated with the hosting galaxy. We then take a stellar
system on a circular orbit inside a galaxy represented as a "frozen" external
field. The equilibrium distribution function is obtained from the one
describing the spherical case by replacing the energy integral with the
relevant Jacobi integral in the presence of the external tidal field. Then the
construction of the model requires the investigation of a singular perturbation
problem for an elliptic partial differential equation with a free boundary, for
which we provide a method of solution to any desired order, with explicit
solutions to two orders. We outline the relevant parameter space, thus opening
the way to a systematic study of the properties of a two-parameter family of
physically justified non-spherical models of quasi-relaxed stellar systems. The
general method developed here can also be used to construct models for which
the non-spherical shape is due to internal rotation. Eventually, the models
will be a useful tool to investigate whether the shapes of globular clusters
are primarily determined by internal rotation, by external tides, or by
pressure anisotropy.Comment: AASTeX v5.2, 37 pages with 2 figures, accepted for publication in The
Astrophysical Journa
Thymosin beta-4 prenatal administration improves fetal development and halts side effects due to preterm delivery
Objective: Thymosin beta 4 (TB4) is the most abundant member of the beta-thymosin family in humans. The main physiological role of TB4 is the regulation of actin polymerization. TB4 is also involved in angiogenesis, cell survival, cell migration and fetal development. The aim of this study was to evaluate the activity of TB4 as a fetal growth promoter when administered during pregnancy.
Materials and methods: Our protocols have been carried out in full conformity with the rules and guidelines expected for this kind of trial. 10 pregnant mice received the same injection regimen. Only 6 of these 10 are part of this experiment because they were pregnant. At 10:00 a.m. on day E14 and E17 of gestation mice were weighed and treated with an intraperitoneal injection of TB4 (Regene RX, Rockville, MD, USA; 6 mg/kg in PBS).
Results: The mothers treated with TB4 for two days precisely E14 and E17, showed a higher cranio-caudal length when compared to control newborns. At histology, maternal TB4 treatment was associated with more advanced development of lungs, heart, kidney, cerebral cortex and notochord.
Conclusions: Our study shows that TB4 administration during gestation may act as a powerful fetal growth promoter, by accelerating the development of newborn organs and tissues
Flinders Island spotted fever rickettsioses caused by "marmionii" strain of rickettsia honei, Eastern Australia
Australia has 4 rickettsial diseases: murine typhus, Queensland tick typhus, Flinders Island spotted fever, and scrub typhus. We describe 7 cases of a rickettsiosis with an acute onset and symptoms of fever (100%), headache (71%), arthralgia (43%), myalgia (43%), cough (43%), maculopapular/petechial rash (43%), nausea (29%), pharyngitis (29%), lymphadenopathy (29%), and eschar (29%). Cases were most prevalent in autumn and from eastern Australia, including Queensland, Tasmania, and South Australia. One patient had a history of tick bite (Haemaphysalis novaeguineae). An isolate shared 99.2%, 99.8%, 99.8%, 99.9%, and 100% homology with the 17 kDa, ompA, gltA, 16S rRNA, and Sca4 genes, respectively, of Rickettsia honei. This Australian rickettsiosis has similar symptoms to Flinders Island spotted fever, and the strain is genetically related to R. honei. It has been designated the "marmionii" strain of R. honei, in honor of Australian physician and scientist Barrie Marmion
Children at risk of domestic accidents when are locked up at home: the other side of COVID-19 outbreak lockdown
Background We proposed to analyze thoroughly the impact of the COVID-19 lockdown (CL) in changes of profiles and in trend of the domestic accidents (DAs) in children. Methods This was a single experience, cross-sectional study conducted at the emergency department (ED) of III trauma center. We enrolled children under 18 years admitted to ED with a diagnosis of DAs comparing the CL period from 10(th) March 2020 to 4(th) May 2020 with the same period of the previous year,10(th) March 2019 to 4(th) May 2019. Results In CL period, the cumulative incidence of ED visits for DAs increased from 86.88 to 272.13 per 1,000 children and the cumulative incidence of hospitalizations for DAs increased from 409.72 to 534.48 per 1,000 children. We reported in CL a decrease in the severity of ED presentation assessed by proxy measures: the level of priority ED visits reduced by 67% in CL period (OR: 0.33; 95%CI 0.22-0.48; p < 0.001); the likelihood of delayed time of presentation to ED increased by 65% in case of domestic injuries occurring in CL period (OR: 1.65; 95% CI: 1.17-2.34; p = 0.004); the odds of transfer from other hospital decreased by 78% in CL (OR: 0.15-0.33; p < 0.001). Children were more at risk of poisoning (OR:3.35-106.11; p = 0.001), of body foreign ingestion (OR: 1.83-14.39; p = 0.002) and less at risk of animal bite trauma (OR:0.05-0.35; p < 0.001). Conclusion Although the need to stay home has made a decisive breakthrough on the spread of COVID-19, the experience from this study underlines how this preventive measure has also had a downside in term of increased cumulative incidence of ED visits and of hospitalizations for DA
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