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1.
Mechanical vibrations seem to affect the behaviour of different cell types and the functions of different organs. Pressure waves, including acoustic waves (sounds), could affect cytoskeletal molecules via coherent changes in their spatial organization and mechano-transduction signalling. We analyzed the sounds spectra and their fractal features. Cardiac muscle HL1 cells were exposed to different sounds, were stained for cytoskeletal markers (phalloidin, beta-actin, alpha-tubulin, alpha-actinin-1), and studied with multifractal analysis (using FracLac for ImageJ). A single cell was live-imaged and its dynamic contractility changes in response to each different sound were analysed (using Musclemotion for ImageJ). Different sound stimuli seem to influence the contractility and the spatial organization of HL1 cells, resulting in a different localization and fluorescence emission of cytoskeletal proteins. Since the cellular behaviour seems to correlate with the fractal structure of the sound used, we speculate that it can influence the cells by virtue of the different sound waves’ geometric properties that we have photographed and filmed. A theoretical physical model is proposed to explain our results, based on the coherent molecular dynamics. We stress the role of the systemic view in the understanding of the biological activity.  相似文献   
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Over the past decade, telomeres have attracted increasing attention due to the role they play in human fertility. However, conflicting results have been reported on the possible association between sperm telomere length (STL) and leukocyte telomere length (LTL) and the quality of the sperm parameters. The aim of this study was to run a comprehensive study to investigate the role of STL and LTL in male spermatogenesis and infertility. Moreover, the association between the sperm parameters and 11 candidate single nucleotide polymorphisms (SNPs), identified in the literature for their association with telomere length (TL), was investigated. We observed no associations between sperm parameters and STL nor LTL. For the individual SNPs, we observed five statistically significant associations with sperm parameters: considering a p < 0.05. Namely, ACYP2˗rs11125529 and decreased sperm motility (p = 0.03); PXK˗rs6772228 with a lower sperm count (p = 0.02); NAF1˗rs7675998 with increased probability of having abnormal acrosomes (p = 0.03) and abnormal flagellum (p = 0.04); ZNF208˗rs8105767 and reduction of sperms with normal heads (p = 0.009). This study suggests a moderate involvement of telomere length in male fertility; however, in our analyses four SNPs were weakly associated with sperm variables, suggesting the SNPs to be pleiotropic and involved in other regulatory mechanisms independent of telomere homeostasis, but involved in the spermatogenic process.  相似文献   
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Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18–25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes’ expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment.  相似文献   
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Recent research on mast cell biology has turned its focus on MRGPRX2, a new member of the Mas-related G protein-coupled subfamily of receptors (Mrgprs), originally described in nociceptive neurons of the dorsal root ganglia. MRGPRX2, a member of this group, is present not only in neurons but also in mast cells (MCs), specifically, and potentially in other cells of the immune system, such as basophils and eosinophils. As emerging new functions for this receptor are studied, a variety of both natural and pharmacologic ligands are being uncovered, linked to the ability to induce receptor-mediated MC activation and degranulation. The diversity of these ligands, characterized in their human, mice, or rat homologues, seems to match that of the receptor’s interactions. Natural ligands include host defense peptides, basic molecules, and key neuropeptides such as substance P and vasointestinal peptide (known for their role in the transmission of pain and itch) as well as eosinophil granule-derived proteins. Exogenous ligands include MC secretagogues such as compound 48/80 and mastoparan, a component of bee wasp venom, and several peptidergic drugs, among which are members of the quinolone family, neuromuscular blocking agents, morphine, and vancomycin. These discoveries shed light on its capacity as a multifaceted participant in naturally occurring responses within immunity and neural stimulus perception, as in responses at the center of immune pathology. In host defense, the mice Mrgprb2 has been proven to aid mast cells in the detection of peptidic molecules from bacteria and in the release of peptides with antimicrobial activities and other immune mediators. There are several potential actions described for it in tissue homeostasis and repair. In the realm of pathologic response, there is evidence to suggest that this receptor is also involved in chronic inflammation. Furthermore, MRGPRX2 has been linked to the pathophysiology of non-IgE-mediated immediate hypersensitivity drug reactions. Different studies have shown its possible role in other allergic diseases as well, such as asthma, atopic dermatitis, contact dermatitis, and chronic spontaneous urticaria. In this review, we sought to cover its function in physiologic processes and responses, as well as in allergic and nonallergic immune disease.  相似文献   
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Immune Thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibodies-mediated platelet destruction, a prevalence of M1 pro-inflammatory macrophage phenotype and an elevated T helper 1 and T helper 2 lymphocytes (Th1/Th2) ratio, resulting in impairment of inflammatory profile and immune response. Macrophages are immune cells, present as pro-inflammatory classically activated macrophages (M1) or as anti-inflammatory alternatively activated macrophages (M2). They have a key role in ITP, acting both as effector cells, phagocytizing platelets, and, as antigen presenting cells, stimulating auto-antibodies against platelets production. Eltrombopag (ELT) is a thrombopoietin receptor agonist licensed for chronic ITP to stimulate platelet production. Moreover, it improves T and B regulatory cells functions, suppresses T-cells activity, and inhibits monocytes activation. We analyzed the effect of ELT on macrophage phenotype polarization, proposing a new possible mechanism of action. We suggest it as a mediator of macrophage phenotype switch from the M1 pro-inflammatory type to the M2 anti-inflammatory one in paediatric patients with ITP, in order to reduce inflammatory state and restore the immune system function. Our results provide new insights into the therapy and the management of ITP, suggesting ELT also as immune-modulating drug.  相似文献   
8.
Cannabis use among pregnant women is increasing worldwide along with permissive sociocultural attitudes toward it. Prenatal cannabis exposure (PCE), however, is associated with adverse outcome among offspring, ranging from reduced birth weight to child psychopathology. We have previously shown that male rat offspring prenatally exposed to Δ9-tetrahydrocannabinol (THC), a rat model of PCE, exhibit extensive molecular, cellular, and synaptic changes in dopamine neurons of the ventral tegmental area (VTA), resulting in a susceptible mesolimbic dopamine system associated with a psychotic-like endophenotype. This phenotype only reveals itself upon a single exposure to THC in males but not females. Here, we characterized the impact of PCE on female behaviors and mesolimbic dopamine system function by combining in vivo single-unit extracellular recordings in anesthetized animals and ex vivo patch clamp recordings, along with neurochemical and behavioral analyses. We find that PCE female offspring do not show any spontaneous or THC-induced behavioral disease-relevant phenotypes. The THC-induced increase in dopamine levels in nucleus accumbens was reduced in PCE female offspring, even when VTA dopamine activity in vivo and ex vivo did not differ compared to control. These findings indicate that PCE impacts mesolimbic dopamine function and its related behavioral domains in a sex-dependent manner and warrant further investigations to decipher the mechanisms determining this sex-related protective effect from intrauterine THC exposure.  相似文献   
9.
This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry  相似文献   
10.
We report novel molecules incorporating the nontoxic squalene scaffold and different carbonic anhydrase inhibitors (CAIs). Potent inhibitory action, in the low-nanomolar range, was detected against isoforms hCA II for sulfonamide derivatives, which proved to be selective against this isoform over the tumor-associate hCA IX and XII isoforms. On the other hand, coumarin derivatives showed weak potency but high selectivity against the tumor-associated isoform CA IX. These compounds are interesting candidates for preclinical evaluation in glaucoma or various tumors in which the two enzymes are involved. In addition, an in silico study of inhibitor-bound hCA II revealed extensive interactions with the hydrophobic pocket of the active site and provided molecular insights into the binding properties of these new inhibitors.  相似文献   
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