553 resultados para paraffin


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Access to affordable and renewable sources of energy is crucial to reducing poverty and enhancing rural development in countries of the global South. Straight vegetable oil was recently identified as a possible alternative to conventional biomass for rural energy supply. In this context, the Jatropha curcas Linn. species has been extensively investigated with regard to its potential as a biofuel feedstock. In contrast, only little is known about Jatropha mahafalensis Jum. & H. Perrier, which is an indigenous and endemic representative of the Jatropha genus in Madagascar. This paper explores the potential and suitability of J. mahafalensis as a biofuel feedstock. Seed samples were collected in the area of Soalara in south-western Madagascar in February and September 2011. Two agro-ecological zones (coastal area and calcareous plateau) and two plant age groups (below and above 10 years) were considered. These four sample groups were analyzed with regard to oil properties, element contents, and fatty acid profiles. Measured values differed greatly between the two harvests, probably owing to different climatic or storage conditions. No direct relation between age of trees or location and oil quality could be established. The analyses indicate that J. mahafalensis oil can be used in oil lamps, cooking stoves and stationary combustion engines for electrification or for biodiesel production. However, modifications in storage and extraction methods, as well as further processing steps are necessary to enable its utilization as a straight vegetable oil and feedstock for biodiesel production. If these technical requirements can be met, and if it turns out that J. mahafalensis oil is economically competitive in comparison with firewood, charcoal, paraffin and petroleum, it can be considered as a promising feedstock for rural energy supply.

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Human papilloma virus (HPV) infection of the uterine cervix is linked to the pathogenesis of cervical cancer. Preclinical in vitro and in vivo studies using HPV-containing human cervical carcinoma cell lines have shown that the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, and epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor, erlotinib, can induce growth delay of xenografts. Activation of Akt and mTOR are also observed in cervical squamous cell carcinoma and, the expression of phosphorylated mTOR was reported to serve as a marker to predict response to chemotherapy and survival of cervical cancer patients. Therefore, we investigated: a) the expression level of EGFR in cervical squamous cell carcinoma (SCC) and high-grade squamous intraepithelial lesions (HSIL) versus non-neoplastic cervical squamous epithelium; b) the state of activation of the mTOR pathway in these same tissues; and c) any impact of these signal transduction molecules on cell cycle. Formalin-fixed paraffin-embedded tissue microarray blocks containing 20 samples each of normal cervix, HSIL and invasive SCC, derived from a total of 60 cases of cervical biopsies and cervical conizations were examined. Immunohistochemistry was utilized to detect the following antigens: EGFR; mTOR pathway markers, phosphorylated (p)-mTOR (Ser2448) and p-p70S6K (Thr389); and cell cycle associated proteins, Ki-67 and S phase kinase-associated protein (Skp)2. Protein compartmentalization and expression were quantified in regard to proportion (0-100%) and intensity (0-3+). Mitotic index (MI) was also assessed. An expression index (EI) for pmTOR, p-p70S6K and EGFR, respectively was calculated by taking the product of intensity score and proportion of positively staining cells. We found that plasmalemmal EGFR expression was limited to the basal/parabasal cells (2-3+, EI = 67) in normal cervical epithelium (NL), but was diffusely positive in all HSIL (EI = 237) and SCC (EI 226). The pattern of cytoplasmic p-mTOR and nuclear p-p70S6K expression was similar to that of EGFR; all showed a significantly increased EI in HSIL/SCC versus NL (p<0.02). Nuclear translocation of p-mTOR was observed in all SCC lesions (EI = 202) and was significantly increased versus both HSIL (EI = 89) and NL (EI = 54) with p<0.015 and p<0.0001, respectively. Concomitant increases in MI and proportion of nuclear Ki-67 and Skp2 expression were noted in HSIL and SCC. In conclusion, morphoproteomic analysis reveals constitutive activation and overexpression of the mTOR pathway in HSIL and SCC as evidenced by: increased nuclear translocation of pmTOR and p-p70S6K, phosphorylated at putative sites of activation, Ser2448 and Thr389, respectively; correlative overexpression of the upstream signal transducer, EGFR, and increases in cell cycle correlates, Skp2 and mitotic indices. These results suggest that the mTOR pathway plays a key role in cervical carcinogenesis and targeted therapies may be developed for SCC as well as its precursor lesion, HSIL.

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Background: High grade serous carcinoma whether ovarian, tubal or primary peritoneal, continues to be the most lethal gynecologic malignancy in the USA. Although combination chemotherapy and aggressive surgical resection has improved survival in the past decade the majority of patients still succumb to chemo-resistant disease recurrence. It has recently been reported that amplification of 5q31-5q35.3 is associated with poor prognosis in patients with high grade serous ovarian carcinoma. Although the amplicon contains over 50 genes, it is notable for the presence of several members of the fibroblast growth factor signaling axis. In particular acidic fibroblast growth factor (FGF1) has been demonstrated to be one of the driving genes in mediating the observed prognostic effect of the amplicon in ovarian cancer patients. This study seeks to further validate the prognostic value of fibroblast growth receptor 4 (FGFR4), another candidate gene of the FGF/FGFR axis located in the same amplicon. The emphasis will be delineating the role the FGF1/FGFR4 signaling axis plays in high grade serous ovarian carcinoma; and test the feasibility of targeting the FGF1/FGFR4 axis therapeutically. Materials and Methods: Spearman and Pearson correlation studies on data generated from array CGH and transcriptome profiling analyses on 51 microdissected tumor samples were used to identify genes located on chromosome 5q31-35.3 that showed significant correlation between DNA and mRNA copy numbers. Significant correlation between FGF1 and FGFR4 DNA copy numbers was further validated by qPCR analysis on DNA isolated from 51 microdissected tumor samples. Immunolocalization and quantification of FGFR4 expression were performed on paraffin embedded tissue samples from 183 cases of high-grade serous ovarian carcinoma. The expression was then correlated with clinical data to assess impact on survival. The expression of FGF1 and FGFR4 in vitro was quantified by real-time PCR and western blotting in six high-grade serous ovarian carcinoma cell lines and compared to those in human ovarian surface epithelial cells to identify overexpression. The effect of FGF1 on these cell lines after serum starvation was quantified for in vitro cellular proliferation, migration/invasion, chemoresistance and survival utilizing a combination of commercially available colorimetric, fluorometric and electrical impedance assays. FGFR4 expression was then transiently silenced via siRNA transfection and the effects on response to FGF1, cellular proliferation, and migration were quantified. To identify relevant cellular pathways involved, responsive cell lines were transduced with different transcription response elements using the Cignal-Lenti reporter system and treated with FGF1 with and without transient FGFR4 knock down. This was followed by western blot confirmation for the relevant phosphoproteins. Anti-FGF1 antibodies and FGFR trap proteins were used to attempt inhibition of FGF mediated phenotypic changes and relevant signaling in vitro. Orthotopic intraperitoneal tumors were established in nude mice using serous cell lines that have been previously transfected with luciferase expressing constructs. The mice were then treated with FGFR trap protein. Tumor progression was then followed via bioluminescent imaging. The FGFR4 gene from 52 clinical samples was sequenced to screen for mutations. Results: FGFR4 DNA and mRNA copy numbers were significantly correlated and FGFR4 DNA copy number was significantly correlated with that of FGF1. Survival of patients with high FGFR4 expressing tumors was significantly shorter that those with low expression(median survival 28 vs 55 month p< 0.001) In a multivariate cox regression model FGFR expression significantly increased risk of death (HR 2.1, p<0.001). FGFR4 expression was significantly higher in all cell lines tested compared to HOSE, OVCA432 cell line in particular had very high expression suggesting amplification. FGF1 was also particularly overexpressed in OVCA432. FGF1 significantly increased cell survival after serum deprivation in all cell lines. Transient knock down of FGFR4 caused significant reduction in cell migration and proliferation in vitro and significantly decreased the proliferative effects of FGF1 in vitro. FGFR1, FGFR4 traps and anti-FGF1 antibodies did not show activity in vitro. OVCA432 transfected with the cignal lenti reporter system revealed significant activation of MAPK, NFkB and WNT pathways, western blotting confirmed the results. Reverse phase protein array (RPPA) analysis also showed activation of MAPK, AKT, WNT pathways and down regulation of E Cadherin. FGFR trap protein significantly reduced tumor growth in vivo in an orthotopic mouse model. Conclusions: Overexpression and amplification of several members of the FGF signaling axis present on the amplicon 5q31-35.3 is a negative prognostic indicator in high grade serous ovarian carcinoma and may drive poor survival associated with that amplicon. Activation of The FGF signaling pathway leads to downstream activation of MAPK, AKT, WNT and NFkB pathways leading to a more aggressive cancer phenotype with increased tumor growth, evasion of apoptosis and increased migration and invasion. Inhibition of FGF pathway in vivo via FGFR trap protein leads to significantly decreased tumor growth in an orthotopic mouse model.

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Currently, there are no molecular biomarkers that guide treatment decisions for patients with head and neck squamous cell carcinoma (HNSCC). Several retrospective studies have evaluated TP53 in HNSCC, and results have suggested that specific mutations are associated with poor outcome. However, there exists heterogeneity among these studies in the site and stage of disease of the patients reviewed, the treatments rendered, and methods of evaluating TP53 mutation. Thus, it remains unclear as to which patients and in which clinical settings TP53 mutation is most useful in predicting treatment failure. In the current study, we reviewed the records of a cohort of patients with advanced, resectable HNSCC who received surgery and post-operative radiation (PORT) and had DNA isolated from fresh tumor tissue obtained at the time of surgery. TP53 mutations were identified using Sanger sequencing of exons 2-11 and the associated splice regions of the TP53 gene. We have found that the group of patients with either non-disruptive or disruptive TP53 mutations had decreased overall survival, disease-free survival, and an increased rate of distant metastasis. When examined as an independent factor, disruptive mutation was strongly associated with the development of distant metastasis. As a second aim of this project, we performed a pilot study examining the utility of the AmpliChip® p53 test as a practical method for TP53 sequencing in the clinical setting. AmpliChip® testing and Sanger sequencing was performed on a separate cohort of patients with HNSCC. Our study demonstrated the ablity of the AmpliChip® to call TP53 mutation from a single formalin-fixed paraffin-embedded slide. The results from AmpliChip® testing were identical with the Sanger method in 11 of 19 cases, with a higher rate of mutation calls using the AmpliChip® test. TP53 mutation is a potential prognostic biomarker among patients with advanced, resectable HNSCC treated with surgery and PORT. Whether this subgroup of patients could benefit from the addition of concurrent or induction chemotherapy remains to be evaluated in prospective clinical trials. Our pilot study of the p53 AmpliChip® suggests this could be a practical and reliable method of TP53 analysis in the clinical setting.

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The plasma membrane xc- cystine/glutamate transporter mediates cellular uptake of cystine in exchange for intracellular glutamate and is highly expressed by pancreatic cancer cells. The xCT gene, encoding the cystine-specific xCT protein subunit of xc-, is important in regulating intracellular glutathione (GSH) levels, critical for cancer cell protection against oxidative stress, tumor growth and resistance to chemotherapeutic agents including platinum. We examined 4 single nucleotide polymorphisms (SNPs) of the xCT gene in 269 advanced pancreatic cancer patients who received first line gemcitabine with or without cisplatin or oxaliplatin. Genotyping was performed using Taqman real-time PCR assays. A statistically significant correlation was noted between the 3' untranslated region (UTR) xCT SNP rs7674870 and overall survival (OS): Median survival time (MST) was 10.9 and 13.6 months, respectively, for the TT and TC/CC genotypes (p = 0.027). Stratified analysis showed the genotype effect was significant in patients receiving gemcitabine in combination with platinum therapy (n = 145): MST was 10.5 versus 14.1 months for the TT and TC/CC genotypes, respectively (p = 0.013). The 3' UTR xCT SNP rs7674870 may correlate with OS in pancreatic cancer patients receiving gemcitabine and platinum combination therapy. Paraffin-embedded core and surgical biopsy tumor specimens from 98 patients with metastatic pancreatic adenocarcinoma were analyzed by immunohistochemistry using an xCT specific antibody. xCT protein IHC expression scores were analyzed in relation to overall survival in 86 patients and genotype in 12 patients and no statistically significant association was found between the level of xCT IHC expression score and overall survival (p = 0.514). When xCT expression was analyzed in terms of treatment response, no statistically significant associations could be determined (p = 0.908). These data suggest that polymorphic variants of xCT may have predictive value, and that the xc- transporter may represent an important target for therapy in pancreatic cancer.

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The vertebrate $\beta$-galactoside-binding lectins galectin-1 and galectin-3 have been proposed to function in diverse cellular processes such as adhesion, proliferation, differentiation, and tumorigenesis. Experiments were initiated to further study the functional properties of these molecules. A prostate cancer cell line, LNCaP, was identified which expressed neither galectin. This line was stably transfected with cDNA for either galectin-1 or galectin-3. The resultant clones were used to study effects on critical cell processes. LNCaP cells expressing galectin-1 on the surface were found to bind more rapidly than control lines to the human extracellular matrix proteins laminin and fibronectin, although overall binding was not increased. To analyze effects on differentiation, LNCaP cells were studied which had either been transfected with galectin-1 or which had been induced to express endogenous galectin-1 by treatment with the differentiation agent sodium butyrate. In both cases, cells displayed a slower rate of growth and increased rate of apoptosis. A transient decrease in expression of prostate specific antigen was seen in the butyrate treated cells but not in the transfected cells. To investigate the role of galectins in the process of malignant transformation and progression, immunohistochemical analysis was performed on formalin-fixed, paraffin-embedded sections of human prostate tissue, the premalignant lesion prostatic intraepithelial neoplasia, primary adenocarcinoma of the prostate, and foci of metastatic prostate cancer. Galectin-1 expression was relatively constant throughout in contrast to galectin-3 which demonstrated significantly less expression in primary and metastatic tumors. LNCaP cells transfected with galectin-3 cDNA displayed lower proliferation rates, increased spontaneous apoptosis, and G1 growth phase arrest compared to controls. Four of six galectin-3 lines tested were less tumorigenic in nude mice than controls. The following conclusions are drawn regarding the role of galectin-1 and galectin-3 expression in the context of prostate cancer: (1) galectin-1 may participate in the early stages of cancer cell adhesion to extracellular matrix proteins; (2) galectin-1 expression results in a differentiated phenotype and may contribute to differentiation induction by butyrate; (3) galectin-3 expression correlates inversely with prostate cell tumorigenesis and prostate cancer metastasis. ^

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At birth, the mammalian lung is still immature. The alveoli are not yet formed and the interairspace walls contain two capillary layers which are separated by an interstitial core. After alveolarization (first 2 postnatal weeks in rats) the alveolar septa mature: their capillary layers merge, the amount of connective tissue decreases, and the mature lung parenchyma is formed (second and third week). During the first 3 wk of life the role of tissue transglutaminase (tTG) was studied in rat lung by immunostaining of cryostat and paraffin sections, by Northern and Western blotting, and by a quantitative determination of gamma-glutamyl-epsilon-lysine. While enzyme activity and intracellular tTG were already present before term, the enzyme product (gamma-glutamyl-epsilon-lysine-crosslink) and extracellular tTG appeared between postnatal days 10 and 19 in the lung parenchyma. In large blood vessels and large airways, which mature earlier than the parenchyma, both the enzyme product and extracellular tTG had already appeared at the end of the first postnatal week. We conclude that tTG is expressed and externalized into the extracellular matrix of lung shortly before maturation of an organ area. Because tTG covalently and irreversibly crosslinks extracellular matrix proteins, we hypothesize that it may prevent or delay further remodeling of basement membranes and may stabilize other extracellular components, such as microfibrils.

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Background:Recently, fibroblast growth factor receptor 1 (FGFR1) was discovered in squamous cell carcinomas (SCC) of the lung with FGFR1 amplification described as a promising predictive marker for anti-FGFR inhibitor treatment. Only few data are available regarding prevalence, prognostic significance and clinico-pathological characteristics of FGFR1-amplified and early-stage non-small cell lung carcinomas (NSCLC). We therefore investigated the FGFR1 gene status in a large number of well-characterised early-stage NSCLC.Methods:FGFR1 gene status was evaluated using a commercially available fluorescent in situ hybridisation (FISH) probe on a tissue microarray (TMA). This TMA harbours 329 resected, formalin-fixed and paraffin-embedded, nodal-negative NSCLC with a UICC stage I-II. The FISH results were correlated with clinico-pathological features and overall survival (OS).Results:The prevalence of an FGFR1 amplification was 12.5% (41/329) and was significantly (P<0.0001) higher in squamous cell carcinoma (SCC) (20.7%) than in adenocarcinoma (2.2%) and large cell carcinoma (13%). Multivariate analysis revealed significantly (P=0.0367) worse 5-year OS in patients with an FGFR1-amplified NSCLC.Conclusions:FGFR1 amplification is common in early-stage SCC of the lung and is an independent and adverse prognostic marker. Its potential role as a predictive marker for targeted therapies or adjuvant treatment needs further investigation.

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Pulmonary airways are subdivided into conducting and gas-exchanging airways. An acinus is defined as the small tree of gas-exchanging airways, which is fed by the most distal purely conducting airway. Until now a dissector of five consecutive sections or airway casts were used to count acini. We developed a faster method to estimate the number of acini in young adult rats. Right middle lung lobes were critical point dried or paraffin embedded after heavy metal staining and imaged by X-ray micro-CT or synchrotron radiation-based X-rays tomographic microscopy. The entrances of the acini were counted in three-dimensional (3D) stacks of images by scrolling through them and using morphological criteria (airway wall thickness and appearance of alveoli). Segmentation stopper were placed at the acinar entrances for 3D visualizations of the conducting airways. We observed that acinar airways start at various generations and that one transitional bronchiole may serve more than one acinus. A mean of 5612 (±547) acini per lung and a mean airspace volume of 0.907 (±0.108) μL per acinus were estimated. In 60-day-old rats neither the number of acini nor the mean acinar volume did correlate with the body weight or the lung volume.

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Low back pain is a common ailment in dogs, particularly in specific breeds such as the German shepherd dog. A number of structures such as facet joint capsules, ligaments, dorsal root ganglia, periosteum, vertebral endplates and meninges have been associated with this condition. Yet, in spite of all diagnostic efforts, the origin of pain remains obscure in a substantial proportion of all cases. A further structure often being involved in vertebral column disorders is the intervertebral disc. The presence of nerves, however, is a precondition for pain sensation and, consequently, structures lacking innervation can be left out of consideration as a cause for low back pain. Nerve fibres have been demonstrated at the periphery of the intervertebral disc in man, rabbit and rat. With regard to the dog, however, the extent of intervertebral disc innervation is still being disputed. The goal of the present study, therefore, was to substantiate and expand current knowledge of intervertebral disc innervation. Protein gene product (PGP) 9.5 was used for immunohistochemical examination of serial transversal and sagittal paraffin sections of lumbar discs from adult dogs. This general marker revealed nerve fibres to be confined to the periphery of the intervertebral discs. These results indicate that even limited pathological processes affecting the outer layers of the intervertebral disc are prone to cause low back pain.

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The aim of our study was to evaluate the quality of histo- and cytomorphological features of PAXgene-fixed specimens and their suitability for histomorphological classification in comparison to standard formalin fixation. Fifteen colon cancer tissues were collected, divided into two mirrored samples and either formalin fixed (FFPE) or PAXgene fixed (PFPE) before paraffin embedding. HE- and PAS-stained sections were scanned and evaluated in a blinded, randomised ring trial by 20 pathologists from Europe and the USA using virtual microscopy. The pathologists evaluated histological grading, histological subtype, presence of adenoma, presence of lymphovascular invasion, quality of histomorphology and quality of nuclear features. Statistical analysis revealed that the reproducibility with regard to grading between both fixation methods was rather satisfactory (weighted kappa statistic (k w) = 0.73 (95 % confidence interval (CI), 0.41-0.94)), with a higher agreement between the reference evaluation and the PFPE samples (k w = 0.86 (95 % CI, 0.67-1.00)). Independent from preservation method, inter-observer reproducibility was not completely satisfactory (k w = 0.60). Histomorphological quality parameters were scored equal or better for PFPE than for FFPE samples. For example, overall quality and nuclear features, especially the detection of mitosis, were judged significantly better for PFPE cases. By contrast, significant retraction artefacts were observed more frequently in PFPE samples. In conclusion, our findings suggest that the PAXgene Tissue System leads to excellent preservation of histomorphology and nuclear features of colon cancer tissue and allows routine morphological diagnosis.

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Histomorphological features of colorectal cancers (CRC) represent valuable prognostic indicators for clinical decision making. The invasive margin is a central feature for prognostication shaped by the complex processes governing tumor-host interaction. Assessment of the tumor border can be performed on standard paraffin sections and shows promise for integration into the diagnostic routine of gastrointestinal pathology. In aggressive CRC, an extensive dissection of host tissue is seen with loss of a clear tumor-host interface. This pattern, termed "infiltrative tumor border configuration" has been consistently associated with poor survival outcome and early disease recurrence of CRC-patients. In addition, infiltrative tumor growth is frequently associated with presence of adverse clinicopathological features and molecular alterations related to aggressive tumor behavior including BRAFV600 mutation. In contrast, a well-demarcated "pushing" tumor border is seen frequently in CRC-cases with low risk for nodal and distant metastasis. A pushing border is a feature frequently associated with mismatch-repair deficiency and can be used to identify patients for molecular testing. Consequently, assessment of the tumor border configuration as an additional prognostic factor is recommended by the AJCC/UICC to aid the TNM-classification. To promote the assessment of the tumor border configuration in standard practice, consensus criteria on the defining features and method of assessment need to be developed further and tested for inter-observer reproducibility. The development of a standardized quantitative scoring system may lay the basis for verification of the prognostic associations of the tumor growth pattern in multivariate analyses and clinical trials. This article provides a comprehensive review of the diagnostic features, clinicopathological associations, and molecular alterations associated with the tumor border configuration in early stage and advanced CRC.

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Procurement of fresh tissue of prostate cancer is critical for biobanking and generation of xenograft models as an important preclinical step towards new therapeutic strategies in advanced prostate cancer. However, handling of fresh radical prostatectomy specimens has been notoriously challenging given the distinctive physical properties of prostate tissue and the difficulty to identify cancer foci on gross examination. Here, we have developed a novel approach using ceramic foam plates for processing freshly cut whole mount sections from radical prostatectomy specimens without compromising further diagnostic assessment. Forty-nine radical prostatectomy specimens were processed and sectioned from the apex to the base in whole mount slices. Putative carcinoma foci were morphologically verified by frozen section analysis. The fresh whole mount slices were then laid between two ceramic foam plates and fixed overnight. To test tissue preservation after this procedure, formalin-fixed and paraffin-embedded whole mount sections were stained with hematoxylin and eosin (H&E) and analyzed by immunohistochemistry, fluorescence, and silver in situ hybridization (FISH and SISH, respectively). There were no morphological artifacts on H&E stained whole mount sections from slices that had been fixed between two plates of ceramic foam, and the histological architecture was fully retained. The quality of immunohistochemistry, FISH, and SISH was excellent. Fixing whole mount tissue slices between ceramic foam plates after frozen section examination is an excellent method for processing fresh radical prostatectomy specimens, allowing for a precise identification and collection of fresh tumor tissue without compromising further diagnostic analysis.

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Canine granulocytic anaplasmosis (CGA) is caused by the rickettsial microorganism Anaplasma phagocytophilum. CGA is typically characterized by fever, thrombocytopenia, lethargy, anorexia, arthropy, and other nonspecific clinical signs. Skin lesions have been described in naturally infected lambs and humans. The pathophysiology of CGA is not entirely clear, and the persistence of the organism after the resolution of clinical signs has been described. The aim of the study was to investigate if A. phagocytophilum can be detected in canine lesional skin biopsies from A. phagocytophilum-seropositive dogs with etiologically unclear skin lesions that improved after the treatment with doxycycline. Paraffin-embedded lesional skin biopsies were allocated into separate groups: biopsies from A. phagocytophilum-seropositive dogs responsive to treatment with doxycycline (n=12), biopsies from A. phagocytophilum-seronegative dogs (n=2), and biopsies in which skin lesions histopathologically resembled a tick bite (n=10). The serological status of the latter group was unknown. Histology of the seropositive and seronegative dog skin lesions did not indicate an etiology. DNA was extracted, and a conventional PCR for partial 16S rRNA gene was performed. Anaplasma phagocytophilum DNA was amplified from 4/12 seropositive dogs' skin biopsies. All sequences were 100% identical to the prototype A. phagocytophilum human strain (GenBank accession number U02521). Anaplasma phagocytophilum was not amplified from the 2 seronegative and 10 suspected tick bite dogs. Serum antibody titers of the PCR-positive dogs ranged from 1:200 to 1:2048. Histopathologically, a mild-to-moderate perivascular to interstitial dermatitis composed of a mixed cellular infiltrate and mild-to-moderate edema was seen in all seropositive dogs. In 8/12 seropositive dogs, vascular changes as vasculopathy, fibrinoid necrosis of the vessel walls, and leukocytoclastic changes were observed. In summary, our results support the hypothesis that the persistence of A. phagocytophilum in the skin may be causative for otherwise unexplained skin lesions in seropositive dogs.

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BACKGROUND Prostate cancer (PCa) is a very heterogeneous disease with respect to clinical outcome. This study explored differential DNA methylation in a priori selected genes to diagnose PCa and predict clinical failure (CF) in high-risk patients. METHODS A quantitative multiplex, methylation-specific PCR assay was developed to assess promoter methylation of the APC, CCND2, GSTP1, PTGS2 and RARB genes in formalin-fixed, paraffin-embedded tissue samples from 42 patients with benign prostatic hyperplasia and radical prostatectomy specimens of patients with high-risk PCa, encompassing training and validation cohorts of 147 and 71 patients, respectively. Log-rank tests, univariate and multivariate Cox models were used to investigate the prognostic value of the DNA methylation. RESULTS Hypermethylation of APC, CCND2, GSTP1, PTGS2 and RARB was highly cancer-specific. However, only GSTP1 methylation was significantly associated with CF in both independent high-risk PCa cohorts. Importantly, trichotomization into low, moderate and high GSTP1 methylation level subgroups was highly predictive for CF. Patients with either a low or high GSTP1 methylation level, as compared to the moderate methylation groups, were at a higher risk for CF in both the training (Hazard ratio [HR], 3.65; 95% CI, 1.65 to 8.07) and validation sets (HR, 4.27; 95% CI, 1.03 to 17.72) as well as in the combined cohort (HR, 2.74; 95% CI, 1.42 to 5.27) in multivariate analysis. CONCLUSIONS Classification of primary high-risk tumors into three subtypes based on DNA methylation can be combined with clinico-pathological parameters for a more informative risk-stratification of these PCa patients.