111 research outputs found
Bladder Cancer. Andrea Tubaro, Daniele Santini, Cosimo De Nunzio, Alice Zoccoli, Michele Iuliano. In Biotargets of cancer in current clinical practice. M Bologna Editors. Springer edition. 2012
MicroRNAs and bone metastasis: a new challenge
The development of bone metastases requires multistep and multicellular machinery consisting not only of processes shared with any type of metastases (formation of a pre-metastatic niche, chemotaxis of tumor cells into the host tissue, tumor cells escape from the microvasculature), but also biological interactions that are strictly related to the particular bone microenvironment (bone marrow colonization by cancer cells, osteomimicry, deregulation of bone homeostasis). MiRNAs are highly conserved, small RNAs molecules that regulate gene expression. The functional consequence of miRNA deregulation lies in the mRNA targets whose expression is altered. MiRNA networks acting as upstream regulators of these genes interfere with the initial steps of tumor local invasion and cancer cell intravasation, mainly by regulating the epithelial-mesenchymal transition, the motility, invasiveness and survival abilities of these cells. The miRNA-mediated regulation on the steps of bone tropism, anchorage, homing and finally bone colonization is more tissue specific, being dependent on the expression pattern of target miRNAs in bone marrow sinusoids, bone cells and microenvironment. In that, miRNA specific expression signatures that can distinguish between primary tumors from their corresponding bone metastases might be determinants of clinical aggressiveness. In this review, we focus on the current advances on functions and molecular mechanisms by which miRNAs exert their biological roles in regulating bone metastases development
Modulation of sympathetic vasoconstriction is critical for the effects of sleep on arterial pressure in mice
While values of arterial pressure during sleep are predictive of cardiovascular risk, the autonomic mechanisms underlying the cardiovascular effects of sleep remain poorly understood. Here, we assess the autonomic mechanisms of the cardiovascular effects of sleep in C57Bl/6J mice, taking advantage of a novel technique for continuous intraperitoneal infusion of autonomic blockers. Our results indicate that non-REM sleep decreases arterial pressure by decreasing sympathetic vasoconstriction, decreases heart rate by balancing parasympathetic activation and sympathetic withdrawal, and increases cardiac baroreflex sensitivity mainly by increasing fluctuations in parasympathetic activity. Our results also indicate that REM sleep increases arterial pressure by increasing sympathetic activity to the heart and blood vessels, and increases heart rate, at least in part, by increasing cardiac sympathetic activity. These results provide a framework for generating and testing hypotheses on cardiovascular derangements during sleep in mouse models and human patients
CDKL5 deficiency entails sleep apneas in mice
A recently discovered neurodevelopmental disorder caused by the mutation of the cyclin-dependent kinase-like 5 gene (CDKL5) entails complex autistic-like behaviours similar to Rett syndrome, but its impact upon physiological functions remains largely unexplored. Sleep-disordered breathing is common and potentially life-threatening in patients with Rett syndrome; however, evidence is limited in children with CDKL5 disorder, and is lacking altogether in adults. The aim of this study was to test whether the breathing pattern during sleep differs between adult Cdkl5 knockout (Cdkl5-KO) and wild-type (WT) mice. Using whole-body plethysmography, sleep and breathing were recorded non-invasively for 8 h during the light period. Sleep apneas occurred more frequently in Cdkl5-KO than in WT mice. A receiver operating characteristic (ROC) analysis discriminated Cdkl5-KO significantly from WT mice based on sleep apnea occurrence. These data demonstrate that sleep apneas are a core feature of CDKL5 disorder and a respiratory biomarker of CDKL5 deficiency in mice, and suggest that sleep-disordered breathing should be evaluated routinely in CDKL5 patients
Current pharmacological treatments for COVID-19: What's next?
Since December 2019 SARS-Cov-2 was found responsible for the disease COVID-19, which has spread worldwide. No specific therapies/vaccines are yet available for the treatment of COVID-19. Drug repositioning may offer a strategy and a number of drugs have been repurposed, including lopinavir/ritonavir, remdesivir, favipiravir and tocilizumab. This paper describes the main pharmacological properties of such drugs administered to patients with COVID-19, focusing on their antiviral, immune-modulatory and/or anti-inflammatory actions. Where available, data from clinical trials involving patients with COVID-19 are reported. Preliminary clinical trials seem to support their benefit. However, such drugs in COVID-19 patients have peculiar safety profiles. Thus, adequate clinical trials are necessary for these compounds. Nevertheless, while waiting for effective preventive measures i.e. vaccines, many clinical trials on drugs belonging to different therapeutic classes are currently underway. Their results will help us in defining the best way to treat COVID-19 and reducing its symptoms and complications
Accurate discrimination of the wake-sleep states of mice using non-invasive whole-body plethysmography
A major limitation in the study of sleep breathing disorders in mouse models of pathology is the need to combine whole-body plethysmography (WBP) to measure respiration with electroencephalography/electromyography (EEG/EMG) to discriminate wake-sleep states. However, murine wake-sleep states may be discriminated from breathing and body movements registered by the WBP signal alone. Our goal was to compare the EEG/EMG-based and the WBP-based scoring of wake-sleep states of mice, and provide formal guidelines for the latter. EEG, EMG, blood pressure and WBP signals were simultaneously recorded from 20 mice. Wake-sleep states were scored based either on EEG/EMG or on WBP signals and sleep-dependent respiratory and cardiovascular estimates were calculated. We found that the overall agreement between the 2 methods was 90%, with a high Cohen's Kappa index (0.82). The inter-rater agreement between 2 experts and between 1 expert and 1 naïve sleep investigators gave similar results. Sleep-dependent respiratory and cardiovascular estimates did not depend on the scoring method. We show that non-invasive discrimination of the wake-sleep states of mice based on visual inspection of the WBP signal is accurate, reliable and reproducible. This work may set the stage for non-invasive high-throughput experiments evaluating sleep and breathing patterns on mouse models of pathophysiology
Expression levels of MDR1, MRP1, MRP4, and MRP5 in peripheral blood mononuclear cells from HIV infected patients failing antiretroviral therapy
The aim of the study was to evaluate the mRNA expression of four relevant ABC-transporter genes [MDR1 (P-glycoprotein; Pgp), MRP1, MRP4, and MRP5] in HIV-positive individuals failing treatment and analyze the association between the levels of their expression and viral load, CD4 cell count, and therapeutic history. Ninety-eight HIV-positive samples and 20 samples from healthy donors were analyzed, retrospectively. Peripheral blood mononuclear cells (PBMCs) from HIV1-positive individuals were collected at the time of virological failure. Expression of mRNA of Pgp, MRP1, MRP4, and MRP5 in PBMCs was evaluated by real-time PCR. A high inter-individual variability was observed in both HIV-positive individuals and healthy donors but the expression levels of all mRNA analyzed were significantly higher in the HIV-infected group (P<0.05). A weak but significant inverse correlation was observed between CD4 cell counts and expression levels of MRP4 and MRP5. Comparison of mRNA expression between individuals with different therapeutic histories showed that expression of MRP4 and MRP5 genes in patients who were both protease inhibitor (PI) and non-nucleoside reverse transcriptase inhibitor (NNRTI)experienced was significantly higher than in patients who were PI experienced but NNRTI-naive. In conclusion, the mRNA expression of Pgp, MRP1, MRP4, and MRP5 varies among HIV-infected patients and healthy donors but is significantly higher in HIV-positive patients than in donors. The expression of MRP4 and MRP5 seems to correlate with CD4 cell counts. The same protein seems to be overexpressed in patients receiving NNRTIs. J. Med. Virol. 80:766-771, 2008. (C) 2008 Wiley-Liss, Inc
Daily torpor in laboratory mice: physiological phenotyping and role of orexins.
Spontaneous torpor is a physiological phenomenon used in extreme circumstances to save energy. The physiological mechanisms ruling the torpor bouts are still unknown. Orexins (ORXs) are neuropeptides involved in the control of food behavior, in thermoregulation and sleep-wake cycle regulation this suggests that ORXs could have a role in torpor regulation.
The aims of this study were to elucidate: 1) the role of ORXs in the entrance and/or exiting from torpor; 2) the level of glycemia at the onset of torpor differs from both glucose during arousal from torpor and from baseline conditions.
In order to evaluate the role of orexins, 8 KO-ORX and 8 WT mice, were implanted with a telemetric blood pressure transducer (Data Sciences International, DSI), two cranial electrodes for the discrimination of the wake-sleep state and a thermistor in the brain cortex.
For the study of changes in glycemia related to torpor, 6 WT mice were implanted intraperitoneally with glucose telemeter (DSI). To induce torpor, mice were calorically restricted and exposed to an ambient temperature of 20°C.
The lack of ORXs does not cause significative differences in the physiological parameters during the different torpor phases. During deep torpor, in both the experimental groups, electroencephalogram (EEG) trace is similar to that described during active wakefulness while electromyogram (EMG) is almost flat, similarly to NREM sleep. This unusual sleep tracings can be observed when the minimum Tb is recorded.
We found a strong positive and linear correlation between circulating glucose and Tb during ad libitum feeding at thermoneutrality. Low blood glucose itself was not predictive of a bout of torpor, the onset of torpor was associated with the combination of low blood glucose and hyperactivity
Torpor can be considered a multifactorial and complex mechanism involving both metabolism and central nervous system control
Targeting EGFR in bilio-pancreatic and liver carcinoma
The key role of epidermal growth factor receptor(EGFR) in tumorigenesis has been demonstrated in several cancer types, so recent clinical trials have investigated their activity/efficacy in different settings. Two different types of EGFR-targeted agents were developed: monoclonal antibodies such as cetuximab and panitumumab, and tyrosine kinase inhibitors, such as gefitinib and erlotinib. In this review, we summarize the preclinical rational of potential activity and the most important clinical trials evaluated anti-EGFR targeted agents in non-colorectal digestive cancer, both in monotherapy and in combination with other chemotherapeutic or targeted agents. Patient selection by use of biologic markers will identify which patients are more likely to respond, contributing to the successful use of these agents
Bisphosphonates as anticancer agents in early breast cancer: preclinical and clinical evidence
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