561 research outputs found
Toxic Tau Oligomers Modulated by Novel Curcumin Derivatives
The pathological aggregation and accumulation of tau, a microtubule-associated protein, is a common feature amongst more than 18 different neurodegenerative diseases that are collectively known as tauopathies. Recently, it has been demonstrated that the soluble and hydrophobic tau oligomers are highly toxic in vitro due to their capacity towards seeding tau misfolding, thereby propagating the tau pathology seen across different neurodegenerative diseases. Modulating the aggregation state of tau oligomers through the use of small molecules could be a useful therapeutic strategy to target their toxicity, regardless of other factors involved in their formation. In this study, we screened and tested a small library of newly synthesized curcumin derivatives against preformed recombinant tau oligomers. Our results show that the curcumin derivatives affect and modulate the tau oligomer aggregation pathways, converting to a more aggregated non-toxic state as assessed in the human neuroblastoma SH-SY5Y cell line and primary cortical neuron cultures. These results provide insight into tau aggregation and may become a basis for the discovery of new therapeutic agents, as well as advance the diagnostic field for the detection of toxic tau oligomers
Lymphatic vessels of the dura mater: A new discovery?
Two recent paper s (Aspelund et al. 2015; Louveau et al.
2015) reported the presence in mice of lymphatics in the
cerebra l dura mater , the most external of the meningeal
layers covering the brain. This datum was reporte d as a
novel discovery in the \ufb01elds of neuroanatomy and neuroim-
munology
Non-specific bronchial hyper-responsiveness in children with allergic rhinitis: relationship with the atopic status
An increased prevalence of bronchial hyper-responsiveness (BHR) has been demonstrated in children from a general population, and in non-asthmatic adults with allergic rhinitis. Thus, also children with allergic rhinitis are expected to be at higher risk of BHR. We evaluated the prevalence of BHR in a sample of non-asthmatic children with allergic rhinitis by means of the methacholine (Mch) bronchial challenge, and by monitorizing the airway patency using the daily peak expiratory flow variability (PEFv). Fifty-one children (ranged 6-15 years of age) with allergic rhinitis, ascertained by skin prick test to inhalant allergens, underwent a 14-day peak expiratory flow monitoring, and a Mch bronchial provocation challenge. Thirty healthy children matched for age, and sex served as control group. Thirty-one children in the rhinitis group (61%), and six (20%) in the control group were Mch+ (Mch provocative dose causing a 20% fall of forced expiratory volume in 1 s respect to baseline <2250 microg, equivalent to 11.50 micromol). In rhinitic children the PEFv did not significantly differ between Mch+ and Mch- subjects, but the total serum immunoglobulin E (IgE) were higher among Mch+. The persistent form of rhinitis was significantly associated to Mch positivity. Non-asthmatic children with allergic rhinitis displayed a high prevalence of BHR. The BHR was significantly associated with persistent rhinitis and with higher total IgE levels. Nevertheless, the spontaneous changes in airway patency, as expressed by PEFv, were within normal limits both in Mch+ and Mch- children
The value of immunohistochemical research on PCNA, p53 and heat shock proteins in prostate cancer management: a review.
This review addresses the significance of the expression of proliferating cell nuclear antigen (PCNA), p53 and some heat shock proteins (Hsps) in prostate carcinoma (PC). In fact, PCNA and p53 are two widely discussed tools in PC diagno- sis, mainly because of the controversy regarding the signifi- cance of their expression during prostate cancer development and progression. At the same time, only few studies have shown the potential role of Hsps in carcinogenesis and their overexpression in pre-neoplastic and neoplastic lesions of the prostate. We briefly describe the physiological roles of Hsps in normal cells, and the significance of their immunohistochem- ical detection in PC as well as in pre-cancerous lesions of the prostate. We will also discuss the possible functional interac- tions of these molecules in both dysplastic and neoplastic cell
Circulating levels of adipose products and differences in fat distribution in the ovulatory and anovulatory phenotypes of polycystic ovary syndrome.
Central fat distribution is increased in anovulatory women with polycystic ovary syndrome (PCOS) compared with ovulatory PCOS and matched controls. Among secreted adipocytokines, this is reflected mainly in lower levels of adiponectin
Mechanical strain causes adaptive change in bronchial fibroblasts enhancing profibrotic and inflammatory responses
Asthma is characterized by periodic episodes of bronchoconstriction and reversible airway obstruction; these symptoms are attributable to a number of factors including increased mass and reactivity of bronchial smooth muscle and extracellular matrix (ECM) in asthmatic airways. Literature has suggested changes in cell responses and signaling can be elicited via modulation of mechanical stress acting upon them, potentially affecting the microenvironment of the cell. In this study, we hypothesized that mechanical strain directly affects the (myo)fibroblast phenotype in asthma. Therefore, we characterized responses of bronchial fibroblasts, from 6 normal and 11 asthmatic non-smoking volunteers, exposed to cyclical mechanical strain using flexible silastic membranes. Samples were analyzed for proteoglycans, ?-smooth muscle actin (?SMA), collagens I and III, matrix metalloproteinase (MMP) 2 & 9 and interleukin-8 (IL-8) by qRT-PCR, Western blot, zymography and ELISA. Mechanical strain caused a decrease in ?SMA mRNA but no change in either ?SMA protein or proteoglycan expression. In contrast the inflammatory mediator IL-8, MMPs and interstitial collagens were increased at both the transcriptional and protein level. The results demonstrate an adaptive response of bronchial fibroblasts to mechanical strain, irrespective of donor. The adaptation involves cytoskeletal rearrangement, matrix remodelling and inflammatory cytokine release. These results suggest that mechanical strain could contribute to disease progression in asthma by promoting inflammation and remodelling responses.<br/
Involvement of caspase-3 and GD3 ganglioside in ceramide-induced apoptosis in Farber disease
Farber's disease (FD) is a rare genetic disorder caused by ceramidase deficiency, which results in ceramide accumulation in lung, liver, colon, skeletal muscle, cartilage, and bone. Although this disease has been symptomatically characterized, little is known about its molecular pathogenetic process. Because recent studies reported that ceramide accumulation induces GD3 ganglioside formation and apoptosis, we investigated, in tissue obtained via colonoscopy from seriously involved patients, the possible involvement of ceramide in FD colonocyte destruction. Histochemical and TUNEL analyses of paraffin-embedded sections revealed that 45 ± 4.3% of FD colonocytes showed morphological signs of apoptosis compared with the 8 ± 2.3% of constitutive epithelial cell death. Importantly, immunohistochemical study for pro-apoptotic factors showed that GD3 accumulation colocalized with active caspase-3 and cleaved K18 in FD colon tissue. These findings provide evidence for a role of the apoptotic ceramide pathway in the pathogenesis of FD
Proportional Venn diagram and determinants of allergic respiratory diseases in Italian adolescents
Large variations in prevalence of atopy and allergic diseases are reported worldwide in children, but in epidemiological studies the use of skin prick tests (SPT) and spirometry along with questionnaires is not common in the Mediterranean Area. The present work was aimed at evaluating the prevalence of current asthma (CA), rhinoconjunctivitis (RC), and eczema (E), with atopy and respiratory function, and the role of risk factors for allergic respiratory diseases. A total of 2150 Italian schoolchildren were cross-sectionally investigated through respiratory questionnaire, SPT, and spirometry. A proportional Venn diagram quantified the distribution of CA, RC, and E, stratifying for allergic sensitization to show differences in prevalence of allergic diseases among subjects with and without positive SPT. CA prevalence was 4.2%, RC 17.9%, and E 5.3%. CA and RC increased, while E decreased, with respect to previous local studies. Allergic sensitization prevalence (evaluated as positive response to at least one SPT) was 39.2%. A double Venn diagram identified 15 categories. Atopic CA was threefold more frequent than non-atopic CA. Atopic vs non-atopic RC and E were 9.6% vs 10.3% and 2.0% vs 3.3%, respectively. Atopic vs non-atopic RC associated with CA were 1.6% vs 0.5%; the same figures for RC associated with E were 0.8% vs 1.3%. Asymptomatic atopic subjects were 27.0%. Atopy, RC, parental asthma, and environmental risk factors were associated with CA. Atopy and environmental factors were risk factors also for RC. Asthma and traffic exposure were linked to reduced lung function. Respiratory allergic diseases are still increasing and largely concomitant in Italian adolescents. Atopy is more important for CA than RC. Avoiding exposures to measured environmental risk factors would prevent 41% of current asthma and 34% of rhinoconjunctivitis
Poorly differentiated synovial sarcoma: A case report
Poorly differentiated synovial sarcoma is a rare soft tissue tumor. We studied a case arising in the pleural cavity of a young subject, characterised by the presence of spindle cell, small cell, and large epithelioid cell areas. We performed stains for mucosubstances and analysed the expression of cytokeratins 5/6, 7, 8, 18, 19, CEA, CD34, Ber-Ep4 and calretinin to characterize the phenotype of this neoplasm. We furthermore assessed immunohistochemically the presence of p53, Bcl-2, Bax and caspase 3, four apoptotic markers, to evaluate a relationship between apoptotic activity and the behaviour of this tumor. Our findings showed a strong presence of calretinin, p53 and Bcl-2 in all three areas. The possibility that poorly differentiated synovial sarcoma could be calretinin-positive was a new data, to our knowledge, and it could be of some importance in diagnostic pathology. Moreover, the negligible positivity for Bax and caspase 3 suggested that the minor role of programmed cell death could be one of the causes of the aggressive behaviour of this tumor. These data also suggest that the reduction of apoptotic phenomena in poorly differentiated synovial sarcoma could be considered one of the major mechanisms of tumoral growth
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