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991.
Breast cancer is the most common malignancy among women and the second leading cause of mortality due to cancer worldwide. The complexity of breast cancer resembles an intricate ecosystem comprising various cleverly designed interaction levels of internal and external factors to generate a pliable context in the clonal evolution of breast cancer cells. Principally, the complex entity can become evident toward delineating a number of significant variations in the specific fields of breast cancer analyses, including the molecular, physiological, and morphological characteristics, clinical presentations, risk factors, the histopathological conditions, and response to systemic therapy regarding the maintenance of tumor as a whole. In hindsight, various classification systems developing based on specific inclusion criteria have indisputably changed both our appreciation of the biological demeanor of breast cancer and the main strategies for designing tailored therapy regimens through the proper evaluation of diagnosis and prognostication of given specimens. Here, we endeavor to provide a general overview of different types of breast cancer classification as well as the clinical acceptance of their applications along with the latest findings in this area. Taken together, the major significance of breast cancer management that can be ascertained by operational convergent points of its stratification areas is owing to the fact that the achievement of individualized and targeted therapy may denounce new horizons of surveillance and treatment strategies in which they may function as a rheostat of specific therapy regimens toward reducing the detected distances between experimental data and operating options in clinical practice. 相似文献
992.
Sleep disturbance in patients with multiple sclerosis is prevalent and has multifactorial causes. In mice with experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, we determined the dynamic changes of sleep architecture and the interactions between sleep changes and EAE symptoms. The changes of sleep patterns were mainly reflected by altered sleep stage distribution and increased sleep fragmentation. Increased waking and decreased non-rapid eye movement sleep occurred after EAE onset and persisted through the symptomatic phase. There also was increased sleep state transition, indicating a reduction of sleep cohesiveness. Furthermore, the extent of sleep fragmentation correlated with the severity of disease. This is the first study of sleep characteristics in EAE mice demarcating specific changes related to the autoimmune disorder without confounding factors such as psychosocial impact and treatment effects. The reduction of sleep efficiency and cohesiveness supports the notion that enhancing sleep might facilitate the recovery of mice from EAE, pertinent to the multimodality treatment of multiple sclerosis. 相似文献
993.
BackgroundCurrent guidelines state that the goals of growth hormone (GH) therapy in adults should be an appropriate clinical response, avoidance of side effects, and an IGF-1 value within the age-adjusted reference range. There are no published studies on the target level for IGF-1 that offer specific guidance in this regard.ObjectivesTo compare low-normal and high-normal target levels of IGF-1 on efficacy and safety of GH treatment.MethodsA randomized, open-label, clinical trial including thirty-two adults from one university hospital receiving GH therapy for at least one year with a stable IGF-1 concentration between − 1 and 1 SD score (SDS). Subjects were randomized to receive either a decrease (IGF-1 target level of − 2 to − 1 SDS) or an increase of their daily GH dose (IGF-1 target level of 1 to 2 SDS) for a period of 24 weeks. The effect on cardiovascular risk factors and physical performance, next to tolerability, was compared.ResultsThirty subjects (65.6% men, mean age 46.6 (SD 9.9) years) could be analyzed. In subjects with a high-normal IGF-1 target level, waist circumference decreased (p = 0.05), and overall they felt better (p = 0.04), compared to subjects with a low-normal IGF-1 target level. However, increasing IGF-1 levels led to more myalgia, and decreasing IGF-1 levels to more fatigue. There was a gender-dependent difference in effect on HDL cholesterol.ConclusionAlthough increasing GH dose to IGF-1 levels between 1 and 2 SDS improved waist circumference and well-being, safety was not guaranteed with the demonstrated effect on HDL cholesterol in men, and reported myalgia. 相似文献
994.
《BONE》2014
BackgroundLittle is known about the effects of adrenal steroids on skeletal maturation and bone mass acquisition in healthy prepubertal boys.ObjectiveTo study whether adrenal-derived steroids within the physiological range are associated with skeletal maturation, areal and volumetric bone mineral density (aBMD and vBMD) and bone geometry in healthy prepubertal and early pubertal boys.Methods98 healthy prepubertal and early pubertal boys (aged 6–14 y) were studied cross-sectionally. Androstenedione (A) and estrone (E1) were determined by liquid chromatography tandem mass spectrometry and DHEAS was determined by immunoassay. Whole body and lumbar spine aBMD and bone area were determined by dual-energy X-ray absorptiometry. Trabecular (distal site) and cortical (proximal site) vBMD and bone geometry were assessed at the non-dominant forearm and leg using peripheral QCT. Skeletal age was determined by X-ray of the left hand.ResultsAdrenal-derived steroids (DHEAS, A and E1) are positively associated with bone age in prepubertal and early pubertal children, independently of age. There are no associations between the adrenal-derived steroids and the studied parameters of bone size (lumbar spine and whole body bone area, trabecular or cortical area at the radius or tibia, periosteal circumference and cortical thickness at the radius or tibia) or BMD (aBMD or vBMD).ConclusionIn healthy prepubertal and early pubertal boys, serum adrenal-derived steroid levels, are associated with skeletal maturation, independently of age, but not with bone size or (v)BMD. Our data suggest that adrenal derived steroids are not implicated in the accretion of bone mass before puberty in boys. 相似文献
995.
996.
《Current problems in cancer》2018,42(6):530-547
Although developments in the diagnosis and therapy of colorectal cancer (CRC) have been made in the last decade, much work remains to be done as it remains the second leading cause of cancer death. It is now well established that epigenetic events, together with genetic alterations, are key events in initiation and progression of CRC. Epigenetics refers to heritable alterations in gene expression that do not involve changes in the DNA sequence. These alterations include DNA methylation, histone alterations, chromatin remodelers, and noncoding RNAs. In CRC, aberrations in epigenome may also involve in the development of drug resistance to conventional drugs such as 5-fluorouracil, oxaliplatin, and irinotecan. Thus, it has been suggested that combined therapies with epigenetic agents may reverse drug resistance. In this regard, DNA methyltransferase inhibitors and histone deacetylase inhibitors have been extensively investigated in CRC. The aim of this review is to provide a brief overview of the preclinical data that represent a proof of principle for the employment of epigenetic agents in CRC with a focus on the advantages of combinatorial therapy over single-drug treatment. We will also critically discuss the results and limitations of initial clinical experiences of epigenetic-based therapy in CRC and summarize ongoing clinical trials. Nevertheless, since recent translational research suggest that epigenetic modulators play a key role in augmenting immunogenicity of the tumor microenvironment and in restoring immune recognition, we will also highlight the recent developments of combinations strategies of immunotherapies and epigenetic therapies in CRC, summarizing preclinical, and clinical data to signify this evolving and promising field for CRC treatment. 相似文献
997.
998.
《Clinical biochemistry》2014,47(1-2):104-110
ObjectiveTo develop a gold nanoparticle (AuNP) assay for direct detection of unamplified HURP RNA in urine.Design and methodsHURP RNA was extracted from urine samples (50 bladder carcinoma patients, 25 benign bladder lesions, and 25 controls) and further purified using magnetic nanoparticles (MNPs), functionalized with HURP RNA-specific oligonucleotides, and then detected by RT-PCR or gold nanoparticles.ResultsThe developed HURP RNA AuNP assay has a sensitivity and a specificity of 88.5% and 94%, respectively, and a detection limit of 2.4 nmol/L. The concordance between the HURP AuNP assay with RT-PCR after RNA purification using functionalized MNPs was 97%.ConclusionsThe developed colorimetric HURP RNA AuNP assay is sensitive, simple, and can aid noninvasive diagnosis of bladder cancer. 相似文献
999.
The paradigm of early drug development in cancer is shifting from ‘histology-oriented’ to ‘molecularly oriented’ clinical trials. This change can be attributed to the vast amount of tumour biology knowledge generated by large international research initiatives such as The Cancer Genome Atlas (TCGA) and the use of next generation sequencing (NGS) techniques developed in recent years. However, targeting infrequent molecular alterations entails a series of special challenges. The optimal molecular profiling method, the lack of standardised biological thresholds, inter- and intra-tumor heterogeneity, availability of enough tumour material, correct clinical trials design, attrition rate, logistics or costs are only some of the issues that need to be taken into consideration in clinical research in small genomically stratified patient populations. This article examines the most relevant challenges inherent to clinical research in these populations. Moreover, perspectives from the Academia point of view are reviewed as well as initiatives to be taken in forthcoming years. 相似文献
1000.
Ulrike Weber-Stadlbauer Juliet Richetto Ramona A. J. Zwamborn Roderick C. Slieker Urs Meyer 《Neuropsychopharmacology》2021,46(2):404
Prenatal exposure to infectious and/or inflammatory insults is increasingly recognized to contribute to the etiology of psychiatric disorders with neurodevelopmental components. Recent research using animal models suggests that maternal immune activation (MIA) can induce transgenerational effects on brain and behavior, possibly through epigenetic mechanisms. Using a mouse model of MIA that is based on gestational treatment with the viral mimeticpoly(I:C) (= polyriboinosinic-polyribocytidilic acid), the present study explored whether the transgenerational effects of MIA are extendable to dopaminergic dysfunctions. We show that the direct descendants born to poly(I:C)-treated mothers display signs of hyperdopaminergia, as manifested by a potentiated sensitivity to the locomotor-stimulating effects of amphetamine (Amph) and increased expression of tyrosine hydroxylase (Th) in the adult ventral midbrain. In stark contrast, second- and third-generation offspring of MIA-exposed ancestors displayed blunted locomotor responses to Amph and reduced expression of Th. Furthermore, we found increased DNA methylation at the promoter region of the dopamine-specifying factor, nuclear receptor-related 1 protein (Nurr1), in the sperm of first-generation MIA offspring and in the ventral midbrain of second-generation offspring of MIA-exposed ancestors. The latter effect was further accompanied by reduced mRNA levels of Nurr1 in this brain region. Together, our results suggest that MIA has the potential to modify dopaminergic functions across multiple generations with opposite effects in the direct descendants and their progeny. The presence of altered DNA methylation in the sperm of MIA-exposed offspring highlights the possibility that epigenetic processes in the male germline play a role in the transgenerational effects of MIA.Subject terms: Neuroimmunology, Developmental disorders 相似文献