Breast cancer (BC) is one of the most prevalent forms of cancer globally, and has recently become the leading cause of cancer-related mortality in women. BC is a heterogeneous disease comprising various histopathological and molecular subtypes with differing levels of malignancy, and each patient has an individual prognosis. Etiology and pathogenesis are complex and involve a considerable number of genetic alterations and dozens of alterations in non-coding RNA expression.
View Article and Find Full Text PDFNon-coding RNAs (ncRNAs) are abundant single-stranded RNA molecules in human cells, involved in various cellular processes ranging from DNA replication and mRNA translation regulation to genome stability defense. MicroRNAs are multifunctional ncRNA molecules of 18-24 nt in length, involved in gene silencing through base-pair complementary binding to target mRNA transcripts. piwi-interacting RNAs are an animal-specific class of small ncRNAs sized 26-31 nt, responsible for the defense of genome stability via the epigenetic and post-transcriptional silencing of transposable elements.
View Article and Find Full Text PDFBreast cancer remains the most frequently diagnosed form of female's cancer, and in recent years it has become the most common cause of cancer death in women worldwide. Like many other tumours, breast cancer is a histologically and biologically heterogeneous disease. In recent years, considerable progress has been made in diagnosis, subtyping, and complex treatment of breast cancer with the aim of providing best suited tumour-specific personalized therapy.
View Article and Find Full Text PDFThe laser radiation absorbed by cells induces production of reactive oxygen species (ROS), followed by the development of oxidative stress. Proteins are major targets for ROS due to their abundance in biological systems. The aim of the present pilot study was to examine the effects of transcutaneous laser blood irradiation (TLBI), i.
View Article and Find Full Text PDFBackground: Biomechanical stress and inflammatory biomarkers relate to global contractility dysfunction; however, adding these biomarkers into a risk model constructed on clinical data does not improve its prediction value in chronic heart failure (CHF).
Aim: The aim of this study was to evaluate whether biomarkers predict declining of left ventricular global contractility function in diabetic patients with ischemia-induced CHF.
Patients And Methods: The study retrospectively evolved 54 diabetic patients who had systolic or diastolic ischemia-induced CHF that was defined as left-ventricular ejection fraction (LVEF) ≤45% or 46-55% respectively assessed by quantitative echocardiography and other conventional criteria according to current clinical guidelines.
Various diseases often result in decompensation requiring resuscitation. In infants moderate hypoxia evokes a compensatory augmented breath - sigh and more severe hypoxia results in a solitary gasp. Progressive asphyxia provokes gasping respiration saving the healthy infant - autoresuscitation by gasping.
View Article and Find Full Text PDFAgonal gasping provoked by asphyxia can save ~15% of mammals even from untreated ventricular fibrillation (VF), but it fails to revive infants with sudden infant death syndrome (SIDS). Our systematic study of airway reflexes in cats and other animals indicated that in addition to cough, there are two distinct airway reflexes that may contribute to auto-resuscitation. Gasp- and sniff-like spasmodic inspirations (SIs) can be elicited by nasopharyngeal stimulation, strongly activating the brainstem generator for inspiration, which is also involved in the control of gasping.
View Article and Find Full Text PDFJ Environ Sci Health A Tox Hazard Subst Environ Eng
August 2012
The aim of the present investigation was to evaluate the effects of multigenerational (P, F1 and F2) exposure to low doses of lead, mercury and cadmium dissolved in tap water on the reproductive potency of Wistar rats and the physical health of their progeny. The animals were divided into 4 groups - control (C) and 3 groups intoxicated by metals (Pb, 100 μM; Hg, 1 μM; Cd, 20 μM, respectively). Females gave births from the 13th to the 78th week of experiment.
View Article and Find Full Text PDFJ Physiol Pharmacol
February 2010
Re-evaluation of our earlier c-Fos-like immuno-reactive studies and brainstem transection/lesion experiments in over 40 anaesthetized, non-paralyzed cats allowed comparison of two distinct airway defensive reflexes with the distinct generators for inspiration (I) and expiration (E), described recently in juvenile rats. The spiration reflex (AspR) is characterized by solitary rapid and strong inspiratory effort with a reciprocal inhibition, preventing a subsequent active expiration, while the expiration reflex (ExpR) manifests by rapid and strong expiratory effort, starting without a preceding, inspiration, or reciprocal inhibition of occasional spontaneous inspiration. The retro-trapezoid nucleus/parafacial respiratory group neurones described as the distinct generator for active E in rats, are activated also during the ExpR in adult cats.
View Article and Find Full Text PDFBackground: Cardioprotective effects by hypoxic preconditioning are well known mainly through in vitro experiments. However, the chronobiological aspects of phenomenon of cardioprotection by hypoxic preconditioning have not been studied in in vitro and in vivo experiments, and there are no consistent data regarding the daytime dependence of preconditioning effects.
Aim: To determine the protective effects of myocardial preconditioning applied during the dark (active) part of the day regimen, and to obtain an understanding concerning chronophysiological aspects of this phenomenon in in vivo rat experiments.
The aim of the study was to determine the dependence of changes in the electrical stability of the heart on the light-dark cycle (LD cycle) in disorders of pulmonary ventilation. The ventricular arrhythmia threshold (VAT) was measured in female Wistar rats (adaptation to the light regime 12:12 h, ketamine/xylazine anesthesia 100 mg/15 mg/kg, i.m.
View Article and Find Full Text PDFObjectives: To determine the effect of the light-dark cycle (LD) and type of anesthetic agent used on changes in the electrical stability of the heart in disorders of pulmonary ventilation.
Methods: The ventricular arrhythmia threshold (VAT) and heart rate (HR) were measured in anesthetized female Wistar rats adapted to an LD regimen of 12 h:12 h (pentobarbital sodium 30 mg/kg, intraperitoneally, or ketamine/xylazine 100 mg/15 mg/kg, intramuscularly; open chest experiments) under artificial normoventilation (tidal volume 1 mL/100 g, respiratory rate 40 breaths/min) and during 20 min of hypoventilation (tidal volume 0.5 mL/100 g, respiratory rate 20 breaths/min) followed by 20 min of reoxygenation.
Four basic control mechanisms of breathing (brainstem respiratory centre, peripheral and central chemoreceptors, intero- and exteroceptive reflexes and suprapontine influences), as well as their sleep-related disorders are analysed. A decrease in central chemoreceptor sensitivity to CO2 and an increase in upper airway resistance during sleep result in hypoventilation and mild hypoxaemia already in physiological conditions. Compensatory increase in ventilatory effort with synchronous inhibition of pharyngeal dilators during sleep reduces the upper airway lumen manifesting with snoring, upper airway resistance syndrome, and OSA.
View Article and Find Full Text PDFMonaldi Arch Chest Dis
October 2000
Cardiorespiratory decompensation or even death may result from dysfunction of upper airway reflexes during sleep. This could manifest, for example, as a lack of pharyngeal dilation in obstructive sleep apnoea or failure of autoresuscitation by gasping in sudden infant death syndrome. Data obtained from experiments in anaesthetized cats suggest several clinicophysiological applications for upper airway reflexes possessing important pathogenetic and therapeutic potentials.
View Article and Find Full Text PDFRespir Physiol
October 1998
Mechanical stimulation of the pharyngeal mucosa in cats and some other mammals evokes the 'aspiration reflex' (AR) characterized by rapid and strong inspiratory efforts not followed by active expirations. It resembles other spasmodic inspiratory acts such as the sniff, the gasp, and the sigh in several aspects, e.g.
View Article and Find Full Text PDFBratisl Lek Listy
January 1998
Bratisl Lek Listy
October 1997
Background: Apnoeic events are often accompanied by various disturbances in electric cardiac activity, the character and development as well as mechanism of which remain broadly unknown suggesting both direct metabolic defects as well as neurogenous autonomic influences.
Methods: Changes in ECG and heart rate induced by repeated short-lasting inhalation of hypoxic poikilocapnic mixtures (100% N2 and/or 0.5-1% CO2 or 6% CO2 in N2) were analyzed in 17 spontaneously breathing cats anaesthetized with sodium pentobarbitone (40 mg.
We analysed in vivo the synaptic mechanisms underlying serotonin-mediated depression of expiratory neuronal discharges and phrenic nerve activity. We report that nucleus raphe obscurus stimulation not only abolishes phrenic nerve activity, but also hyperpolarizes the membrane potential, depresses periodic synaptic drive potentials and thus action potential discharges in caudal medullary expiratory neurons. These effects originate from pre- and post-synaptic inhibitory processes that involve 5-HT-1A receptor activation.
View Article and Find Full Text PDFRespir Physiol
December 1995
Respiratory effects of electrical stimulation of the upper airways (UAW) before and during apnoeic episodes induced by nitrogen inhalation were studied in 9 anaesthetized cats. In eupnoeic animals these electrically-evoked reflexes comprise rapid and powerful inspiratory efforts characterized by strong maximal airway occlusion pressures (Pmax = 635 +/- 39 mm H2O) and rapid peak inspiratory flow rates (PIF = 536 +/- 36 ml.sec-1) similar to the sniff-like aspiration reflex elicited mechanically.
View Article and Find Full Text PDFRespir Physiol
December 1995
Forced inspiratory efforts resembling the sniff-like aspiration reflex (AR) were evoked by single-shocks or trains of electrical impulses to the dorsal pharyngeal and nasal mucosal surfaces in 12 anaesthetized spontaneously breathing cats. The strongest ARs determined by diaphragmatic (DIA) EMG and peak-inspiratory flows were elicited from the dorsolateral nasopharyngeal wall close to the torus tubalis. Highly responsive sites were also detected in the posterolateral nasal cavity and in the rostrolateral oropharynx.
View Article and Find Full Text PDF1. Respiratory neurons of mammals are rhythmically active because their membrane potential fluctuates periodically over a voltage range of -70 to -55 mV. These respiratory drive potentials lead to periodic discharges of bursts of action potentials lasting for 1-2 s.
View Article and Find Full Text PDFVarious flow and timing characteristics of breathing as well as electrocorticographic (ECoG) records were analysed in a model of reversible respiratory failure induced by N2 inhalation in 27 anaesthetized cats. During the first minute of respiratory arrest, nasopharyngeal stimulation by an elastic nylon fibre elicited a typical sniff- or gasp-like aspiration reflex (in 88.8% of cases), whilst similar tracheobronchial irritation evoked a weak cough reaction in one third of cases (34.
View Article and Find Full Text PDFVarious cardiorespiratory and electrophysiological parameters were analysed in a model of acute respiratory failure induced by inhalation of pure nitrogen in approximately 150 anaesthetized cats. Initial hyperventilation leading to apnoea was characterized by extreme hypoxaemia, marked bradycardia and flattening of electrocortical (ECoG) activity. Artificial ventilation applied at the stage of marked mydriasis usually spontaneously prevented cardiovascular failure and normalized vital functions.
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