The effects of endogenous and exogenous androgens on cardiovascular disease risk factors and progression

Cardiovascular disease incidence rates have long been known to significantly differ between the two sexes. Estrogens alone fail to explain this phenomenon, bringing an increasing amount of attention to the role of androgens. Contrary to what was initially hypothesized, androgens seem to have an overall cardioprotective effect, especially in men. Recent studies and published data continue to support this notion displaying a consistent inverse correlation with atherosclerosis progression and cardiovascular disease both in regressive and prospective study models. Clinical studies have also revealed what seems to be a differential androgenic effect on various cardiovascular risk factors between men and women. Further insight indicates that in order to avoid confusion it may be also preferable to separately examine the effects of endogenous androgen levels from exogenous testosterone administration, as well as discern the differential results of low to normal and supraphysiological administration doses. This review summarizes old and recent data according to the above distinctions, in an attempt to further our understanding of the role of androgens in cardiovascular disease

Acoustic Emission during bauxite load

98 σ.Η παρούσα εργασία περιγράφει εργαστηριακές δοκιμές αντοχής πετρώματος, βωξίτη με ταυτόχρονη καταγραφή της εκλυόμενης Ακουστικής Εκπομπής. Ζητούμενο, η καλύτερη δυνατή εκτέλεση των εργαστηριακών δοκιμών, η καταγραφή της Ακουστικής Εκπομπής του πετρώματος και η συσχέτιση αυτής στην πρόγνωση αστοχίας, του πετρώματος. Δείγματα βωξίτη από τα μεταλλεία της εταιρείας S & B στην περιοχή Παρνασσού – Γκίωνας, μεταφέρθηκαν στα εργαστήρια Τεχνολογίας Διάνοιξης Σηράγγων, και Τεχνικής Γεωλογίας όπου και διαμορφώθηκαν σε κυλινδρικά και δισκοειδή δοκίμια για μονοαξονική και αντιδιαμετρική θλίψη αντίστοιχα. Στις δοκιμές χρησιμοποιήθηκε κατάλληλος μηχανολογικός εξοπλισμός (αισθητήρες, ενισχυτές, κα) ώστε να γίνει καταγραφή της δραστηριότητας Ακουστικής Εκπομπής σε πραγματικό χρόνο. Πρώτη παρατήρηση αποτέλεσε ο ίδιος ο βωξίτης, υλικό ψαθυρό και με δύσκολα προβλέψιμη συμπεριφορά. Παρουσίασε διάφορες μορφές αστοχίας, τόσο στις δοκιμές μονοαξονικής θλίψης όσο και αντιδιαμετρικής θλίψης. Κατοπινό συμπέρασμα αποτελεί η σχέση φόρτισης – εκλυόμενης Ακουστικής Εκπομπής. Παρατηρήθηκε η άμεση σχέση αυτών, καθότι έχουν σχέση αιτίου – αιτιατού, αλλά στην περίπτωση του βωξίτη φάνηκε ότι η εκλυόμενη Ακουστική Εκπομπή δεν ήταν πάντα αρκετή ώστε να δώσει προειδοποίηση ότι επέρχεται αστοχία. Κύριο συμπέρασμα επίσης, αυτής της εργασίας αποτελεί η συνειδητοποίηση από μεριάς μου της δουλειάς που πρέπει να προηγηθεί για την εκτέλεση μιας εργαστηριακής δοκιμής και πόσο μάλλον ώστε αυτή να θεωρείται σύμφωνη με τα διεθνή πρότυπα.The present study covers laboratory tests for rock strength, bauxite, together with record of the emitted Acoustic Emission. Object of research the best possible laboratory tests performance, record the rock's Acoustic Emission and correlation in prediction of rock failure. Bauxite samples from S & B mines in the Parnassos area were transported to the lab, where they shaped to cylindrical and discoid for uniaxial and brazilian splitting compression correspondly. Appropriate hardware (sensors, amplifier etc) was used so that recording of Acoustic Emission activity is performed in real time. First observation, comprises bauxite itself, a brittle and difficult to predict its performance material. Differently types of failure were observed in the uniaxial compression as long as in the brazial splitting compression. Later observation was the association of load – emitted Acoustic Emission. The direct connection of those two was marked, for they have a cause – effect contact, but in the case of bauxite it appears that the emitted Acoustic Emission was not always enough so that a markable warning of expected failure is drawn. Along with this study it became conscious to me the amount of work that needs to be done for executing laboratory tests according to international standards.Σωτήριος Ι. Μπακογιάννη

Phytochemicals and cognitive health: Are flavonoids doing the trick?

Flavonoids constitute a large group of polyphenolic compounds with numerous effects on behaviour and cognition. These effects vary from learning and memory enhancement to an improvement of general cognition. Furthermore, flavonoids have been implicated in a) neuronal proliferation and survival, by acting on a variety of cellular signalling cascades, including the ERK/CREB/BDNF and PI3K/Akt pathway, b) oxidative stress reduction and c) relief from Alzheimer's disease-type symptoms. From an electrophysiological aspect, they promote long term potentiation in the hippocampus, supporting the hypothesis of synaptic plasticity mediation. Together, these actions reveal a neuroprotective effect of flavonoid compounds in the brain. Therefore, flavonoid intake could be a potential clinical direction for prevention and/or attenuation of cognitive decline deterioration which accompanies various brain disorders. The purpose of the current review paper was to summarise all these effects on cognition, describe the possible pathways via which they may act on a cellular level and provide a better picture for future research towards this direction. © 2018 The Author

Retention of cervical cerclage after preterm premature rupture of the membranes: a critical appraisal

Purpose: The present meta-analysis aims to assess the efficacy of cervical cerclage retention after the occurrence of preterm premature rupture of the membranes by analyzing the observed maternal and neonatal perinatal outcomes. Methods: We searched Medline (1966–2014), Scopus (2004–2014), Clinicaltrials.org (1997–2014), Cochrane Central Register of Controlled Trials (CENTRAL) (1999–2014) and Google Scholar (2004–2014) search engines, as well as reference lists from all included studies. The statistical analysis was performed using the RevMan software. Results: Six studies were finally included in the present review, involving 293 parturient. Cerclage retention did not significantly prolong the gestational latency period (MD 2.56 days, 95 % CI − 1.06, 6.71). It did, however, increased the rates of delivery after the first 48 h (OR 6.27, 95 % CI 1.08, 36.24). As a technique, it did not significantly increase the rates of neonatal sepsis (OR 1.42, 95 % CI 0.65, 3.12) or the neonatal death rates (OR 1.09, 95 % CI 0.48, 2.47).Maternal chorioamnionitis was, however, significantly more prevalent among women offered cerclage retention (OR 1.78, 95 % CI 1.02, 3.12), although the same was not observed in the case of postpartum endometritis (REM OR 4.73, 95 % CI 0.74, 30.09). Conclusions: Current evidence is insufficient to support the retention of cervical cerclage after the occurrence of PPROM, therefore, its implementation should be exceptionally instituted in everyday clinical practice, until further evidence becomes available. © 2014, Springer-Verlag Berlin Heidelberg

Evaluation of Cerebrovascular Reserve Capacity in Symptomatic and Asymptomatic Internal Carotid Stenosis With Transcranial Doppler

Cerebrovascular reserve capacity (CVRC) is a hemodynamic parameter indicating the brain’s capacity to overcome ischemia. Transcranial Doppler (TCD) is a useful device to measure CVRC, with high availability and low cost. The aim of the study is to investigate asymptomatic patients with affected CVRC, who could benefit from CEA. One hundred and forty five consecutive patients (60 symptomatic and 65 asymptomatic), with internal carotid artery (ICA) stenosis >70 % and 20 healthy individuals without internal carotid stenosis underwent TCD-inhalation CO2 tests in order to measure the CVRC in both hemispheres of each patient. CVRC between asymptomatic and symptomatic patients were significantly different in the 95 % confidence interval (CI) as well as the mean CVRC value in contralateral carotid artery. The correlation between CVRC in the carotid artery with stenosis and the existence of symptoms is significant at the 0.01 level. Additionally, symptoms and CVRC of the contralateral carotid artery are also significant at the 0.05 level and CVRC values in asymptomatic patients and the control group at the 0.01 level. None of the covariant factors, except the age, are significantly correlated with CRVC. CVRC could be an early mark-index to evaluate the risk of stroke in this group of patients and to design their therapeutic approach

Fetal alcohol spectrum disorders and cognitive functions of young children

Fetal alcohol spectrum disorder (FASD) is one of the main causes of mental retardation worldwide. Nearly 1% of children in North America are affected from antenatal exposure to ethanol. Its economic burden in industrialized countries is increasing. It is estimated that, in the United States, 4.0 billion dollars are annually expended in the treatment and rehabilitation of these patients. As a pathologic entity, they present with a broad symptomatology. Fetal alcohol syndrome (FAS) is the most readily recognized clinical manifestation of these disorders. Various factors seem to contribute in the pathogenesis of FASD-related cognitive disorders. During the last 20 years, several potential pretranslational and posttranslational factors have been extensively studied in various experimental animal models. Research has specifically focused on several neurotransmitters, insulin resistance, alterations of the hypothalamic-pituitary-adrenal (HPA) axis, abnormal glycosylation of several proteins, oxidative stress, nutritional antioxidants, and various epigenetic factors. The purpose of the present review is to summarize the clinical manifestations of this disorder during childhood and adolescence and to summarize the possible pathophysiologic and epigenetic pathways that have been implicated in the pathophysiology of FASD. © 2014 by De Gruyter

A Case of SARS-CoV-2 Clinical Relapse after 4 Negative RT-PCR Tests in Greece: Recurrence or Reinfection?

SARS-CoV-2 pandemic is the greatest public health concern of the year 2020. There are several worldwide reports of patients who have managed to recover from SARS-CoV-2 infection with negative PCR test results, that for unknown reasons convert back to positive PCR. We report a case of a patient in our hospital who developed positive PCR test results for SARS-CoV-2, after 4 consecutive results that were negative, along with a full-blown clinical syndrome of SARS-CoV-2 infection. © The Author(s) 2021

Effets bénéfiques de la chrononutrition sur les altérations de mémoire associées à l’obésité chez la souris

Une alimentation trop riche en gras et en sucre (HFD) affecte non seulement le métabolisme et le système cardiovasculaire mais aussi le fonctionnement cérébral. Cela est particulièrement préoccupant chez l’adolescent qui montre souvent une alimentation déséquilibrée et chez qui le cerveau est toujours en maturation. Chez la souris, nous avons montré que la consommation d’un régime HFD durant l’adolescence affecte des processus de mémoire associés à l’hippocampe alors que le même régime consommé par un animal adulte n’entraine pas de déficits. La chrononutrition ayant prouvé ses effets bénéfiques sur le métabolisme, nous avons testé ses effets potentiels sur la mémoire chez des souris ayant consommé un régime HFD pendant l’adolescence. Nos résultats montrent que les souris soumises au régime HFD restreint dans le temps ne développe pas les déficits de mémoire observés chez les souris sous régime HFD ad libitum. Afin de comprendre les mécanismes moléculaires impliqués nous avons étudiés l’oscillation circadienne d’un ensemble de gènes exprimés dans l’hippocampe dans les différents groupes expérimentaux. Nous montrons que 49% des gènes montrant une oscillation circadienne sous régime contrôle perdent cette oscillation sous régime HFD ad libitum. Grâce à la chrononutrition 60% de ces gènes récupèrent une rythmicité circadienne. Parmi ces gènes, notre attention s’est focalisée sur le récepteur aux glucocorticoïdes (GR) dont l’implication dans la mémoire est connue. Nous confirmons une hyperactivation du GR hippocampique chez les animaux sous régime HFD ad libitum ainsi que la prévention des déficits de mémoire par blocage pharmacologique du GR

Contemporary Strategies in the Management of Civilian Abdominal Vascular Trauma

The evaluation and management of patients with abdominal vascular trauma or injury requires immediate and effective decision-making in these unfavorable circumstances. The majority of these patients arrive at trauma centers in profound shock, secondary to massive blood loss, which is often unrelenting. Moreover, ischemia, compartment syndrome, thrombosis, and embolization may also be life threatening and require immediate intervention. To minimize the risk of these potentially lethal complications, early understanding of the disease process and emergent therapeutic intervention are necessary. In the literature, the management of acute traumatic vascular injuries is restricted to traditional open surgical techniques. However, in penetrating injuries surgeons often face a potentially contaminated field, which renders the placement of prosthetic grafts inappropriate. Currently, however, there are sparse data on the management of vascular trauma with endovascular techniques. The role of endovascular technique in penetrating abdominal vascular trauma, which is almost always associated with severe active bleeding, is limited. It is worth mentioning that hybrid operating rooms with angiographic radiology capabilities offer more opportunities for the management of this kind of injuries by either temporary control of the devastating bleeding using endovascular balloon tamponade or with embolization and stenting. On the other hand, blunt abdominal injuries are less dangerous and they could be treated at most times by endovascular means. Since surgeons continue to encounter abdominal vascular trauma, open and endovascular techniques will evolve constantly giving us encouraging messages for the near future

Prenatal cocaine exposure and its impact on cognitive functions of offspring: A pathophysiological insight

It is estimated that approximately 0.5%-3% of fetuses are prenatally exposed to cocaine (COC). The neurodevelopmental implications of this exposure are numerous and include motor skill impairments, alterations of social function, predisposition to anxiety, and memory function and attention deficits; these implications are commonly observed in experimental studies and ultimately affect both learning and IQ. According to previous studies, the clinical manifestations of prenatal COC exposure seem to persist at least until adolescence. The pathophysiological cellular processes that underlie these impairments include dysfunctional myelination, disrupted dendritic architecture, and synaptic alterations. On a molecular level, various neurotransmitters such as serotonin, dopamine, catecholamines, and γ-Aminobutyric acid seem to participate in this process. Finally, prenatal COC abuse has been also associated with functional changes in the hormones of the hypothalamic-pituitary-Adrenal axis that mediate neuroendocrine responses. The purpose of this review is to summarize the neurodevelopmental consequences of prenatal COC abuse, to describe the pathophysiological pathways that underlie these consequences, and to provide implications for future research in the field. © 2016 by De Gruyter