The meaning of different forms of structural myocardial injury, immune response and timing of infarct necrosis and cardiac repair

Although a decline in the all-cause and cardiac mortality rates following myocardial infarction (MI) during the past 3 decades has been reported, MI is a major cause of death and disability worldwide. From a pathological point of view MI consists in a particular myocardial cell death due to prolonged ischemia. After the onset of myocardial ischemia, cell death is not immediate, but takes a finite period of time to develop. Once complete myocytes’ necrosis has occurred, a process leading to a healed infarction takes place. In fact, MI is a dynamic process that begins with the transition from reversible to irreversible ischemic injury and culminates in the replacement of dead myocardium by a fibrous scar. The pathobiological mechanisms underlying this process are very complex, involving an inflammatory response by several pathways, and pose a major challenge to ability to improve our knowledge. An improved understanding of the pathobiology of cardiac repair after MI and further studies of its underlying mechanisms provide avenues for the development of future strategies directed toward the identification of novel therapies. The chronologic dating of MI is of great importance both to clinical and forensic investigation, that is, the ability to create a theoretical timeline upon which either clinicians or forensic pathologists may increase their ability to estimate the time of MI. Aging of MI has very important practical implications in clinical practice since, based on the chronological dating of MI, attractive alternatives to solve therapeutic strategies in the various phases of MI are developing

Donor selection for allogenic hemopoietic stem cell transplantation: clinical and ethical considerations

Allogenic hematopoietic progenitor cell transplantation (allo-HSCT) is an established treatment for many diseases. Stem cells may be obtained from different sources: mobilized peripheral blood stem cells, bone marrow, and umbilical cord blood. The progress in transplantation procedures, the establishment of experienced transplant centres, and the creation of unrelated adult donor registries and cord blood banks gave those without an human leucocyte antigen- (HLA-) identical sibling donor the opportunity to find a donor and cord blood units worldwide. HSCT imposes operative cautions so that the entire donation/transplantation procedure is safe for both donors and recipients; it carries with it significant clinical, moral, and ethical concerns, mostly when donors are minors. The following points have been stressed: the donation should be excluded when excessive risks for the donor are reasonable, donors must receive an accurate information regarding eventual adverse events and health burden for the donors themselves, a valid consent is required, and the recipient’s risks must be outweighed by the expected benefits. The issue of conflict of interest, when the same physician has the responsibility for both donor selection and recipient care, is highlighted as well as the need of an adequate insurance protection for all the parties involved

Confocal laser scanning microscope, raman microscopy and western blotting to evaluate inflammatory response after myocardial infarction

Cardiac muscle necrosis is associated with inflammatory cascade that clears the infarct from dead cells and matrix debris, and then replaces the damaged tissue with scar, through three overlapping phases: the inflammatory phase, the proliferative phase and the maturation phase. Western blotting, laser confocal microscopy, Raman microscopy are valuable tools for studying the inflammatory response following myocardial infarction both humoral and cellular phase, allowing the identification and semiquantitative analysis of proteins produced during the inflammatory cascade activation and the topographical distribution and expression of proteins and cells involved in myocardial inflammation. Confocal laser scanning microscopy (CLSM) is a relatively new technique for microscopic imaging, that allows greater resolution, optical sectioning of the sample and three-dimensional reconstruction of the same sample. Western blotting used to detect the presence of a specific protein with antibody-antigen interaction in the midst of a complex protein mixture extracted from cells, produced semi-quantitative data quite easy to interpret. Confocal Raman microscopy combines the three-dimensional optical resolution of confocal microscopy and the sensitivity to molecular vibrations, which characterizes Raman spectroscopy. The combined use of western blotting and confocal microscope allows detecting the presence of proteins in the sample and trying to observe the exact location within the tissue, or the topographical distribution of the same. Once demonstrated the presence of proteins (cytokines, chemokines, etc.) is important to know the topographical distribution, obtaining in this way additional information regarding the extension of the inflammatory process in function of the time stayed from the time of myocardial infarction. These methods may be useful to study and define the expression of a wide range of inflammatory mediators at several different timepoints providing a more detailed analysis of the time course of the infarct

Cardiac oxidative stress and inflammatory cytokines response after myocardial infarction

Oxidative stress in heart failure or during ischemia/reperfusion occurs as a result of the excessive generation or accumulation of free radicals or their oxidation products. Free radicals formed during oxidative stress can initiate lipid peroxidation, oxidize proteins to inactive states and cause DNA strand breaks. Oxidative stress is a condition in which oxidant metabolites exert toxic effects because of their increased production or an altered cellular mechanism of protection. In the early phase of acute heart ischemia cytokines have the feature to be functional pleiotropy and redundancy, moreover, several cytokines exert similar and overlapping actions on the same cell type and one cytokine shows a wide range of biological effects on various cell types. Activation of cytokine cascades in the infarcted myocardium was established in numerous studies. In experimental models of myocardial infarction, induction and release of the pro-inflammatory cytokines like TNF-&alpha (Tumor Necrosis Factor &alpha), IL-1&beta (Interleukin- 1&beta) and IL-6 (Interleukin-6) and chemokines are steadily described. The current review examines the role of oxidative stress and pro-inflammatory cytokines response following acute myocardial infarction and explores the inflammatory mechanisms of cardiac injur

Lipid peroxidation and apoptotic response in rat brain areas induced by long-term administration of nandrolone: the mutual crosstalk between ROS and NF-kB

The aim of this study was to evaluate the played by oxidative stress in the apoptotic response in different brain areas of rats chronically treated with supra-physiological doses of nandrolone decanoate (ND). Immunohistochemical study and Western blot analysis were performed to evaluate cells' apoptosis and to measure the effects of expression of specific mediators, such as NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), Bcl-2 (B-cell lymphoma 2), SMAC/DIABLO (second mitochondria-derived activator of caspases/direct IAP-binding protein with low PI) and VMAT2 (vesicular monoamine transporter 2) on apoptosis. The results of the present study indicate that a long-term administration of ND promotes oxidative injury in rat brain specific areas. A link between oxidative stress and NF-κB signalling pathways is supported by our results. In addition to high levels of oxidative stress, we consistently observed a strong immunopositivity to NF-κB. It has been argued that one of the pathways leading to the activation of NF-κB could be under reactive oxygen species (ROS)-mediated control. In fact, growing evidence suggests that although in limited doses, endogenous ROS may play an activating role in NF-κB signalling, while above a certain threshold, they may negatively impact upon this signalling. However, a mutual crosstalk between ROS and NF-κB exists and recent studies have shown that ROS activity is subject to negative feedback regulation by NF-κB, and that this negative regulation of ROS is the means through which NF-κB counters programmed cells

Classification of stillbirths is an ongoing dilemma

Aim: To compare different classification systems in a cohort of stillbirths undergoing a comprehensive workup; to establish whether a particular classification system is most suitable and useful in determining cause of death, purporting the lowest percentage of unexplained death. Methods: Cases of stillbirth at gestational age 22–41 weeks occurring at the Department of Gynecology and Obstetrics of Foggia University during a 4 year period were collected. The World Health Organization (WHO) diagnosis of stillbirth was used. All the data collection was based on the recommendations of an Italian diagnostic workup for stillbirth. Two expert obstetricians reviewed all cases and classified causes according to five classification systems. Results: Relevant Condition at Death (ReCoDe) and Causes Of Death and Associated Conditions (CODAC) classification systems performed best in retaining information. The ReCoDe system provided the lowest rate of unexplained stillbirth (14%) compared to de Galan-Roosen (16%), CODAC (16%), Tulip (18%), Wigglesworth (62%). Conclusion: Classification of stillbirth is influenced by the multiplicity of possible causes and factors related to fetal death. Fetal autopsy, placental histology and cytogenetic analysis are strongly recommended to have a complete diagnostic evaluation. Commonly employed classification systems performed differently in our experience, the most satisfactory being the ReCoDe. Given the rate of “unexplained” cases, none can be considered optimal and further efforts are necessary to work out a clinically useful system

A theoretical timeline for myocardial infarction: immunohistochemical evaluation and western blot quantification for Interleukin-15 and Monocyte chemotactic protein-1 as very early markers

Background: Experimental and human studies have demonstrated that innate immune mechanisms and consequent inflammatory reaction play a critical role in cardiac response to ischemic injury. Thus, the detection of immuno-inflammatory and cellular phenomena accompanying cardiac alterations during the early inflammatory phase of myocardial infarction (MI) may be an excellent diagnostic tool. Current knowledge of the chronology of the responses of myocardial tissue following the occurrence of ischemic insult, as well as the existence of numerous studies aiming to identify reliable markers in dating MI, induced us to investigate the myocardial specimens of MI fatal cases in order to better define the age of MI. Methods: We performed an immunohistochemical study and a Western blot analysis to evaluate detectable morphological changes in myocardial specimens of fatal MI cases and to quantify the effects of cardiac expression of inflammatory mediators (CD15, IL-1 β, IL-6, TNF-α, IL-15, IL-8, MCP-1, ICAM-1, CD18, tryptase) and structural and functional cardiac proteins. Results: We observed a biphasic course of MCP-1: it was strongly expressed in the very early phase (0-4 hrs), to diminish in the early period (after 6-8 hrs). Again, our choice of IL-15 is explained by the synergism with neutrophilic granulocytes (CD15) and our study shows the potential for striking cytokine synergy in promoting fast, local neutrophil response in damaged tissues. A progressively stronger immunoreaction for the CD15 antibody was visible in the areas where the margination of circulating inflammatory cells was detectable, up to very strong expression in the oldest ones (>12 hours). Further, the induction of CD15, IL-15, MCP-1 expression levels was quantified by Western blot analysis. The resultswereasfollows:IL-15/β-actin 0.80, CD15/ β-actin 0.30, and MCP-1/β-actin 0.60, matching perfectly with the results of immunohistochemistry. Control hearts from traumatic death cases did not show any immunoreactivity to the pro-inflammatory markers, neither were there any reactions in Western blot analysis. Conclusions: Essential markers (i.e. IL-15, MCP-1) are suitable indicators of myocardial response to ischemic insult involving very early phase reaction (inflammatory response and cytokine release). In the very near future, proteomics may help clinicians and pathologists to better understand mechanisms relating to cardiac repair and remodeling and provide targets for future therapies

Regurgitation in healthy and non healthy infants

Uncomplicate regurgitation in otherwise healthy infants is not a disease. It consists of milk flow from mouth during or after feeding. Common causes include overfeeding, air swallowed during feeding, crying or coughing; physical exam is normal and weight gain is adequate. History and physical exam are diagnostic, and conservative therapy is recommended. Pathologic gastroesophageal reflux or gastroesophageal reflux disease refers to infants with regurgitation and vomiting associated with poor weight gain, respiratory symptoms, esophagitis. Reflux episodes occur most often during transient relaxations of the lower esophageal sphincter unaccompanied by swallowing, which permit gastric content to flow into the esophagus. A minor proportion of reflux episodes occurs when the lower esophageal sphincter fails to increase pressure during a sudden increase in intraabdominal pressure or when lower esophageal sphincter resting pressure is chronically reduced. Alterations in several protective mechanisms allow physiologic reflux to become gastroesophageal reflux disease; diagnostic approach is both clinical and instrumental: radiological series are useful to exclude anatomic abnormalities; pH-testing evaluates the quantity, frequency and duration of the acid reflux episodes; endoscopy and biopsy are performed in the case of esophagitis. Therapy with H2 receptor antagonists and proton pump inhibitors are suggested

Dynamic characterisation of interlaminar fracture toughness in carbon fibre epoxy composite laminates

In this work, the rate dependence of mode I interlaminar fracture toughness for two different materials systems, IM7/8552 and IM7/M91, both unidirectional UD carbon-fibre epoxy composite laminates have been examined over a wide range of loading rates from 0.5 mm/min up to 2000 mm/s at room temperature. Quasi-static fracture tests were performed using a DCB (double-cantilever beam) method with a screw-driven testing machine, while the dynamic tests were carried out using a WIF (wedge-insert fracture) specimen loaded dynamically in a hydraulic system. For performing the tests at high displacement rates, a special setup was designed and manufactured which allowed the insertion of the wedge within the DCB specimens at different cross-head displacement rates. The experimental technique used a pair of strain gauges attached to the bending surface of one of the arms of the cantilever beams and far from the initial crack tip. The peak values of the recorded strain were used to determine the fracture toughness under dynamic conditions through use of the compliance calibration method. A finite element model was developed to check the consistency of the measurements and validate the data reduction method used. The results exhibited rate insensitive behaviour in the case of the IM7/8552 laminates while IM7/M91 showed the contrary behaviour with maximum peak at 500 mm/s of displacement rate, with a toughness increase of 95% with respect to the quasi-static conditions.The research leading to these results has received funding from the European Union as Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 722096, DYNACOMP project