959 resultados para Histological biomarker
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Subtle structural differencescan be observed in the islets of Langer-hans region of microscopic image of pancreas cell of the rats having normal glucose tolerance and the rats having pre-diabetic(glucose intolerant)situa-tions. This paper proposes a way to automatically segment the islets of Langer-hans region fromthe histological image of rat's pancreas cell and on the basis of some morphological feature extracted from the segmented region the images are classified as normal and pre-diabetic.The experiment is done on a set of 134 images of which 56 are of normal type and the rests 78 are of pre-diabetictype. The work has two stages: primarily,segmentationof theregion of interest (roi)i.e. islets of Langerhansfrom the pancreatic cell and secondly, the extrac-tion of the morphological featuresfrom the region of interest for classification. Wavelet analysis and connected component analysis method have been used for automatic segmentationof the images. A few classifiers like OneRule, Naïve Bayes, MLP, J48 Tree, SVM etc.are used for evaluation among which MLP performed the best.
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The objective of this study was to determine the origin of organic matter incorporated in Amazon forest soils subjected to vegetation fire by analyzing the aliphatic biomarkers (n-alkanes) present in lipid extracts of soil samples.
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The Cancer Genome Atlas (TCGA) collaborative project identified four distinct prognostic groups of endometrial carcinoma (EC) based on molecular alterations: (i) the ultramutated subtype that encompassed POLE mutated (POLE) cases; (ii) the hypermutated subtype, characterized by MisMatch Repair deficiency (MMRd); (iii) the copy-number high subtype, with p53 abnormal/mutated features (p53abn); (iv) the copy-number low subtype, known as No Specific Molecular Profile (NSMP). Although the prognostic value of TCGA molecular classification, NSMP tumors present a wide variability in molecular alterations and biological aggressiveness. This study aims to investigate the impact of ARID1A and CTNNB1/β-catenin alterations by targeted Next-generation sequencing (NGS) and immunohistochemistry (IHC) in a consecutive series of 125 molecularly classified ECs. NGS and IHC were used to assign surrogate TCGA groups and to identify molecular alterations of multiple target genes including POLE, PTEN, ARID1A, CTNNB1, TP53. Associations with clinicopathologic parameters, molecular subtypes, and outcomes identified NSMP category as the most heterogeneous group in terms of clinicopathologic features and outcome. Integration of surrogate TCGA molecular classification with ARID1A and β-catenin analysis showed NSMP cases with ARID1A mutation characterized by the worst outcome with early recurrence, while NSMP tumors with ARID1A wild-type and β-catenin alteration had indolent clinicopathologic features and no recurrence. This study indicates how the identification of ARID1A and β-catenin alterations in EC represents a simple and effective way to characterize NSMP tumor aggressiveness and metastatic potential.
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Background and Objectives: Carotid revascularization to prevent future vascular events is reasonable in patients with high-grade carotid stenosis. Currently, several biomarkers to predict carotid plaque development and progression have been investigated, among which microRNAs (miRs) are promising tools for the diagnosis of atherosclerosis. Methods and Results: A total of 49 participants were included in the study, divided into two main populations: Population 1 comprising symptomatic and asymptomatic inpatients, and Population 2 comprising asymptomatic outpatients. The study consisted of two main phases: a preliminary discovery phase and a validation phase, applying different techniques. MiR-profiles were performed on plasma and plaque tissue samples obtained from 4 symptomatic and 4 asymptomatic inpatients. MiRs emerging from profiling comparisons, i.e. miR-126-5p, miR-134-5p, miR-145-5p, miR-151a-5p, miR-34b, miR-451a, miR-720 and miR-1271-5p, were subjected to validation through RT-qPCR analysis in the total cohort of donors. Comparing asymptomatic and symptomatic inpatients, significant differences were reported in the expression levels of c-miRs for miR-126-5p and miR-1271-5p in blood, being more expressed in symptomatic subjects. In contrast, simultaneous evaluation of the selected miRs in plaque tissue samples did not confirm data obtained by the miR profiling, and no significant differences were observed. Using Receiver-Operating Characteristic (ROC) analysis, a circulating molecular signature (mir-126-5p, miR-1271-5p, albumin, C-reactive protein, and monocytes) was identified, allowing the distinction of the two groups in Population 1 (AUC = 0.795). Conclusions: Data emerging from this thesis suggest that c-miRs (i.e. miR-126-5p, miR-1271-5p) combined with selected haemato-biochemical parameters (albumin, C-reactive protein, and monocytes) produced a good molecular 'signature' to distinguish asymptomatic and symptomatic inpatients. C-miRs in blood do not necessarily reflect the expression levels of the same miRs in carotid plaque tissues since different mechanism can influence their expression.
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Introduction Only a proportion of patients with advanced NSCLC benefit from Immune checkpoint blockers (ICBs). No biomarker is validated to choose between ICBs monotherapy or in combination with chemotherapy (Chemo-ICB) when PD-L1 expression is above 50%. The aim of the present study is to validate the biomarker validity of total Metabolic Tumor Volume (tMTV) as assessed by 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography ([18F]FDG-PET) Material and methods This is a multicentric retrospective study. Patients with advanced NSCLC treated with ICBs, chemotherapy plus ICBs and chemotherapy were enrolled in 12 institutions from 4 countries. Inclusion criteria was a positive PET scan performed within 42 days from treatment start. TMTV was analyzed at each center based on a 42% SUVmax threshold. High tMTV was defined ad tMTV>median Results 493 patients were included, 163 treated with ICBs alone, 236 with chemo-ICBs and 94 with CT. No correlation was found between PD-L1 expression and tMTV. Median PFS for patients with high tMTV (100.1 cm3) was 3.26 months (95% CI 1.94–6.38) vs 14.70 (95% CI 11.51–22.59) for those with low tMTV (p=0.0005). Similarly median OS for pts with high tMTV was 11.4 months (95% CI 8.42 – 19.1) vs 33.1 months for those with low tMTV (95% CI 22.59 – NA), p .00067. In chemo-ICBs treated patients no correlation was found for OS (p = 0.11) and a borderline correlation was found for PFS (p=0.059). Patients with high tMTV and PD-L1 ≥ 50% had a better PFS when treated with combination of chemotherapy and ICBs respect to ICBs alone, with 3.26 months (95% CI 1.94 – 5.79) for ICBs vs 11.94 (95% CI 5.75 – NA) for Chemo ICBs (p = 0.043). Conclusion tMTV is predictive of ICBs benefit, not to CT benefit. tMTV can help to select the best upfront strategy in patients with high tMTV.
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Antimicrobial stewardship programs are gaining more and more relevance in optimizing anti-infective treatment and in preventing the emergence of antimicrobial resistance. Personalization of antimicrobial treatment based on real-time therapeutic drug morning (TDM) and dosing adaptation may represent an important tool in antimicrobial stewardship programs. In this Ph.D project, we aim to focus on differences in pharmacokinetics (PK) for meropenem and piperacillin/tazobactam and host response biomarkers (e.g., C-reactive protein) in severe Gram‐negative related infections occurring in oncohematologic patients. We are interested in identifying optimized model‐based individualized dosing strategies for these antibiotics focusing on biomarkers-guided prediction of PK and pharmacodynamic (PD) parameters using population PK/PD modelling. We expect to identify optimal model‐based dosing targets for these antibiotics for special populations for implementation in TDM routines, and mathematical models characterizing the relationship between biomarkers and outcomes in these populations.
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Quantitative Susceptibility Mapping (QSM) is an advanced magnetic resonance technique that can quantify in vivo biomarkers of pathology, such as alteration in iron and myelin concentration. It allows for the comparison of magnetic susceptibility properties within and between different subject groups. In this thesis, QSM acquisition and processing pipeline are discussed, together with clinical and methodological applications of QSM to neurodegeneration. In designing the studies, significant emphasis was placed on results reproducibility and interpretability. The first project focuses on the investigation of cortical regions in amyotrophic lateral sclerosis. By examining various histogram susceptibility properties, a pattern of increased iron content was revealed in patients with amyotrophic lateral sclerosis compared to controls and other neurodegenerative disorders. Moreover, there was a correlation between susceptibility and upper motor neuron impairment, particularly in patients experiencing rapid disease progression. Similarly, in the second application, QSM was used to examine cortical and sub-cortical areas in individuals with myotonic dystrophy type 1. The thalamus and brainstem were identified as structures of interest, with relevant correlations with clinical and laboratory data such as neurological evaluation and sleep records. In the third project, a robust pipeline for assessing radiomic susceptibility-based features reliability was implemented within a cohort of patients with multiple sclerosis and healthy controls. Lastly, a deep learning super-resolution model was applied to QSM images of healthy controls. The employed model demonstrated excellent generalization abilities and outperformed traditional up-sampling methods, without requiring a customized re-training. Across the three disorders investigated, it was evident that QSM is capable of distinguishing between patient groups and healthy controls while establishing correlations between imaging measurements and clinical data. These studies lay the foundation for future research, with the ultimate goal of achieving earlier and less invasive diagnoses of neurodegenerative disorders within the context of personalized medicine.
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Snakebite is a neglected disease and serious health problem in Brazil, with most bites being caused by snakes of the genus Bothrops. Although serum therapy is the primary treatment for systemic envenomation, it is generally ineffective in neutralizing the local effects of these venoms. In this work, we examined the ability of 7,8,3'-trihydroxy-4'-methoxyisoflavone (TM), an isoflavone from Dipteryx alata, to neutralize the neurotoxicity (in mouse phrenic nerve-diaphragm preparations) and myotoxicity (assessed by light microscopy) of Bothrops jararacussu snake venom in vitro. The toxicity of TM was assessed using the Salmonella microsome assay (Ames test). Incubation with TM alone (200 μg/mL) did not alter the muscle twitch tension whereas incubation with venom (40 μg/mL) caused irreversible paralysis. Preincubation of TM (200 μg/mL) with venom attenuated the venom-induced neuromuscular blockade by 84% ± 5% (mean ± SEM; n = 4). The neuromuscular blockade caused by bothropstoxin-I (BthTX-I), the major myotoxic PLA2 of this venom, was also attenuated by TM. Histological analysis of diaphragm muscle incubated with TM showed that most fibers were preserved (only 9.2% ± 1.7% were damaged; n = 4) compared to venom alone (50.3% ± 5.4% of fibers damaged; n = 3), and preincubation of TM with venom significantly attenuated the venom-induced damage (only 17% ± 3.4% of fibers damaged; n = 3; p < 0.05 compared to venom alone). TM showed no mutagenicity in the Ames test using Salmonella strains TA98 and TA97a with (+S9) and without (-S9) metabolic activation. These findings indicate that TM is a potentially useful compound for antagonizing the neuromuscular effects (neurotoxicity and myotoxicity) of B. jararacussu venom.
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This study aimed at evaluating whether human papillomavirus (HPV) groups and E6/E7 mRNA of HPV 16, 18, 31, 33, and 45 are prognostic of cervical intraepithelial neoplasia (CIN) 2 outcome in women with a cervical smear showing a low-grade squamous intraepithelial lesion (LSIL). This cohort study included women with biopsy-confirmed CIN 2 who were followed up for 12 months, with cervical smear and colposcopy performed every three months. Women with a negative or low-risk HPV status showed 100% CIN 2 regression. The CIN 2 regression rates at the 12-month follow-up were 69.4% for women with alpha-9 HPV versus 91.7% for other HPV species or HPV-negative status (P < 0.05). For women with HPV 16, the CIN 2 regression rate at the 12-month follow-up was 61.4% versus 89.5% for other HPV types or HPV-negative status (P < 0.05). The CIN 2 regression rate was 68.3% for women who tested positive for HPV E6/E7 mRNA versus 82.0% for the negative results, but this difference was not statistically significant. The expectant management for women with biopsy-confirmed CIN 2 and previous cytological tests showing LSIL exhibited a very high rate of spontaneous regression. HPV 16 is associated with a higher CIN 2 progression rate than other HPV infections. HPV E6/E7 mRNA is not a prognostic marker of the CIN 2 clinical outcome, although this analysis cannot be considered conclusive. Given the small sample size, this study could be considered a pilot for future larger studies on the role of predictive markers of CIN 2 evolution.
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Crohn's disease (CD) is associated with complex pathogenic pathways involving defects in apoptosis mechanisms. Recently, mesenteric adipose tissue (MAT) has been associated with CD ethiopathology, since adipose thickening is detected close to the affected intestinal area. However, the potential role of altered apoptosis in MAT of CD has not been addressed. To evaluate apoptosis in the intestinal mucosa and MAT of patients with CD. Samples of intestinal mucosa and MAT from patients with ileocecal CD and from non-inflammatory bowel diseases patients (controls) were studied. Apoptosis was assessed by TUNEL assay and correlated with the adipocytes histological morphometric analysis. The transcriptional and protein analysis of selected genes and proteins related to apoptosis were determined. TUNEL assay showed fewer apoptotic cells in CD, when compared to the control groups, both in the intestinal mucosa and in MAT. In addition, the number of apoptotic cells (TUNEL) correlated significantly with the area and perimeter of the adipose cells in MAT. Transcriptomic and proteomic analysis reveal a significantly lower transcript and protein levels of Bax in the intestinal mucosa of CD, compared to the controls; low protein levels of Bax were found localized in the lamina propria and not in the epithelium of this tissue. Furthermore, higher level of Bcl-2 and low level of Caspase 3 were seen in the MAT of CD patients. The defective apoptosis in MAT may explain the singular morphological characteristics of this tissue in CD, which may be implicated in the pathophysiology of the disease.
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Thiamine deficiency (TD) is the underlying cause of Wernicke's encephalopathy (WE), an acute neurological disorder characterized by structural damage to key periventricular structures in the brain. Increasing evidence suggests these focal histological lesions may be representative of a gliopathy in which astrocyte-related changes are a major feature of the disorder. These changes include a loss of the glutamate transporters GLT-1 and GLAST concomitant with elevated interstitial glutamate levels, lowered brain pH associated with increased lactate production, decreased levels of GFAP, reduction in the levels of glutamine synthetase, swelling, alterations in levels of aquaporin-4, and disruption of the blood-brain barrier. This review focusses on how these manifestations contribute to the pathophysiology of TD and possibly WE.
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This study aimed to identify novel biomarkers for thyroid carcinoma diagnosis and prognosis. We have constructed a human single-chain variable fragment (scFv) antibody library that was selected against tumour thyroid cells using the BRASIL method (biopanning and rapid analysis of selective interactive ligands) and phage display technology. One highly reactive clone, scFv-C1, with specific binding to papillary thyroid tumour proteins was confirmed by ELISA, which was further tested against a tissue microarray that comprised of 229 thyroid tissues, including: 110 carcinomas (38 papillary thyroid carcinomas (PTCs), 42 follicular carcinomas, 30 follicular variants of PTC), 18 normal thyroid tissues, 49 nodular goitres (NG) and 52 follicular adenomas. The scFv-C1 was able to distinguish carcinomas from benign lesions (P=0.0001) and reacted preferentially against T1 and T2 tumour stages (P=0.0108). We have further identified an OTU domain-containing protein 1, DUBA-7 deubiquitinating enzyme as the scFv-binding antigen using two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. The strategy of screening and identifying a cell-surface-binding antibody against thyroid tissues was highly effective and resulted in a useful biomarker that recognises malignancy among thyroid nodules and may help identify lower-risk cases that can benefit from less-aggressive management.
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Nearly 50% of patients with heart failure (HF) have preserved LV ejection fraction, with interstitial fibrosis and cardiomyocyte hypertrophy as early manifestations of pressure overload. However, methods to assess both tissue characteristics dynamically and noninvasively with therapy are lacking. We measured the effects of mineralocorticoid receptor blockade on tissue phenotypes in LV pressure overload using cardiac magnetic resonance (CMR). Mice were randomized to l-nitro-ω-methyl ester (l-NAME, 3 mg/mL in water; n=22), or l-NAME with spironolactone (50 mg/kg/day in subcutaneous pellets; n=21). Myocardial extracellular volume (ECV; marker of diffuse interstitial fibrosis) and the intracellular lifetime of water (τic; marker of cardiomyocyte hypertrophy) were determined by CMR T1 imaging at baseline and after 7 weeks of therapy alongside histological assessments. Administration of l-NAME induced hypertensive heart disease in mice, with increases in mean arterial pressure, LV mass, ECV, and τic compared with placebo-treated controls, while LV ejection fraction was preserved (>50%). In comparison, animals receiving both spironolactone and l-NAME (l-NAME+S) showed less concentric remodeling, and a lower myocardial ECV and τic, indicating decreased interstitial fibrosis and cardiomyocyte hypertrophy (ECV: 0.43 ± 0.09 for l-NAME versus 0.25 ± 0.03 for l-NAME+S, P<0.001; τic: 0.42 ± 0.11 for l-NAME groups versus 0.12 ± 0.05 for l-NAME+S group). Mice treated with a combination of l-NAME and spironolactone were similar to placebo-treated controls at 7 weeks. Spironolactone attenuates interstitial fibrosis and cardiomyocyte hypertrophy in hypertensive heart disease. CMR can phenotype myocardial tissue remodeling in pressure-overload, furthering our understanding of HF progression.
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Lipoid proteinosis is a rare autosomal recessive disease characterized by the deposition of hyaline material in the skin and internal organs. The main clinical features are hoarseness and typical skin lesions. In this report we describe the endoscopic and radiologic findings in a Brazilian female patient presenting extensive gastrointestinal involvement and the evolution of the detected lesions in ten years of follow-up. Initial upper endoscopy and colonoscopy showed a similar pattern of multiple yellowish nodules throughout the esophagus, stomach, duodenum, and colons. Histological analysis confirmed the diagnosis of lipoid proteinosis. In addition, small bowel follow through demonstrated numerous well defined, round, small filling defects throughout the jejunum. Ten years later, the esophageal lesions remained the same, but none of the previous alterations were detected in the stomach, duodenum, and colons. In conclusion, lipoid proteinosis may affect all gastrointestinal organs with the same pattern of macroscopic and microscopic lesions. Some lesions may regress with increasing age.
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Chronic telogen effluvium (CTE), a poorly understood condition, can be confused with or may be a prodrome to female pattern hair loss (FPHL). The pathogenesis of both is related to follicle cycle shortening and possibly to blood supply changes. To analyze a number of histomorphometric and immunohistochemical findings through vascular endothelial growth factor (VEGF), Ki-67, and CD31 immunostaining in scalp biopsies of 20 patients with CTE, 17 patients with mild FPHL and 9 controls. Ki-67 index and VEGF optical density were analyzed at the follicular outer sheath using ImageJ software. CD31 microvessel density was assessed by a Chalkley grid. Significant follicle miniaturization and higher density of nonanagen follicles were found in FPHL, compared with patients with CTE and controls. Ki-67+ index correlated positively with FPHL histological features. The FPHL group showed the highest VEGF optical density, followed by the CTE and control groups. No differences were found in CD31 microvessel density between the three groups. Histomorphometric results establish CTE as a distinct disorder, separate from FPHL from its outset. Its pathogenic mechanisms are also distinct. These findings support the proposed mechanism of 'immediate telogen release' for CTE, leading to cycle synchronization. For FPHL, accelerated anagen follicular mitotic rates and, thus, higher Ki-67 and VEGF values, would leave less time for differentiation, resulting in hair miniaturization.