Induction of erythrophagocytic activity in cultured mouse trophoblast cells by phorbol myristate acetate and all-trans-retinal

Phorbol myristate acetate (PMA) and all-trans-retinal (retinal) were evaluated as possible phagocytic stimulators of cultured, post implantation, trophoblast cells. Ectoplacental cones dissected from 7.5 day-old mouse embryos provided the source of trophoblastic cells. Co-cultures were performed using stimulated and non-stimulated trophoblast cells and erythrocytes under standard conditions. Phagocytic activity was expressed as the total number of phagocytic cells per ectoplacental cone, and as phagosomic vacuoles per trophoblast giant cell, either in the presence or absence of the stimulators. Both chemical agents had similar effects, less than 12 h after stimulation, statistically significant numbers of erythrophagosomes appear in the trophoblast giant cells (TGC). These findings demonstrate that TGC, like neutrophils and macrophages, can be activated to phagocytosis by exogenous factors. This enhanced activity may result from the generation and release of reactive oxygen species. In conclusion, our data suggest that, because stimulation was provided, the remarkable in vivo phagocytic activity of the trophoblast can be maintained under in vitro conditions, allowing study of the pathways and regulatory steps involved in this process.

[Nitrate derivatives in heart failure: physiopathological, clinical, and prognostic features]

The authors make a review about the indications and benefits of the use of nitrates in the treatment of acute and chronic cardiac failure, considering their use for a short and a long period. The advantages are reported, showing the reduction of pulmonary capillary wedge pressure and the increase of systolic output and consequently of the cardiac eject. This effect may be traceable both to the benefic effect on the mitral valve (perhaps incontinent), that in the pericadic "contraist". The reduction of the filling pressures increases the tolerance to the effort, delays the choice of the time for cardiac transplant and prolongs the survival with amelioration.

[Aortic dissection: new diagnostic and therapeutic trends]

The aortic dissection is a relatively infrequent, but very serious event, that needs to be always considered when a thoracic pain with symptoms of ischemia belongs to the origin of the dissection without signs of myocardial infarction. The most simple and commonly accepted classification, includes two variants, according to the Stanford University (A and B). This aspect is very important in order to the treatment which must be preceded by a suitable pharmacological approach followed in any case by the surgery. We outline the importance of the fast diagnostic knowledge and of the therapeutic choice in order to reduce the mortality that is still very high.

[The physiopathological aspects of sudden cardiac death]

In this paper we have tried to clarify the pathophysiological aspects of sudden cardiac death. On a clinical basis, beside the arrhythmias and the coronaropathies, the other functional and/or organic alterations such as myocardiopathies, congenital malformations, myocarditis, primitive or secondary neoplasms and neurophysiological alterations are described as cause of sudden cardiac death.

[Excess of histamine as a possible cause of cardiac arrhythmias]

In this paper we outline the importance or the histamine in the genesis of cardiac arrhythmias. Such an event can verify not only in patients with allergic diseases especially versus specific substances (antibiotics and anesthetics), but also after endoscopy of surgery which make free a large amount of histamine. For this reason, we outline the possible evenience anaphilaxis after coronarography or cardiac surgery with extracorporeal circulation. Therefore it is always very important to modulate the histamine tone to avoid arrhythmias which can be serious.

Ambulatory blood pressure and cardiac rhythm disturbances in elderly hypertensives: relation to left ventricular mass and filling pattern

In order to define cardiac hypertensive involvement a group of 25 consecutive elderly male hypertensive outpatients and 25 age-matched male normotensive controls underwent full non-invasive assessment of cardiac status by resting 12-lead electrocardiography, Doppler-echocardiographic examination and simultaneous ambulatory blood pressure and electrocardiographic monitorings. Elderly hypertensives showed a higher prevalence of electrocardiographic left ventricular hypertrophy, an increased echocardiographic left ventricular mass, an impaired left ventricular filling pattern and more frequent ventricular arrhythmias when compared with normotensive controls. In elderly patients, left ventricular mass was found to be correlated with 24-hour ambulatory blood pressure (r = 0.47, p < 0.01) and 24-hour ambulatory blood pressure variability (r = 0.52, p < 0.01), while ventricular arrhythmias were correlated with left ventricular mass (r = 0.52, p < 0.01), the Doppler synthetic index of diastolic function E/A ratio (r = -0.56, p < 0.01) and both 24-hour systolic (r = 0.54, p < 0.01) and diastolic (r = 0.59, p < 0.01) ambulatory blood-pressure variabilities. These data suggest that hypertension induces in elderly patients an impairment of cardiac structure and function comparable with that already shown in younger hypertensives. Therefore, the assessment of hypertensive target-organ damage currently employed in younger subjects should be also considered in elderly hypertensives, at least when no other relevant medical disease is present.

Cytological aspects of vascular invasion by the trophoblast of Calomys callosus in hepatic tissues

Ectoplacental cones isolated from embryos on the seventh day of pregnancy were transplanted beneath the hepatic capsule of recipient adult animals to document the morphological patterns of vascular invasion by the trophoblast in the absence of the maternal environment and the influence of its peculiar vasculature. Females, and females and males of Calomys callosus, a cricetid rodent, were used, respectively, as embryo donors and recipient animals. Three to 5 days later, the grafted regions were excised and processed for light and electron microscopy. Invasion of the liver parenchyma by the trophoblast progressed along the vascular beds, associated with gradual phagocytosis of hepatic cells, greatly favoring the morphological characterization of invasive steps exhibited by the trophoblast to access the different kinds of vessels, to trespass the various vascular components and the different levels of the surrounding hepatic parenchyma. It is possible that either in utero during the establishment of embryomaternal circulation in early pregnancy or ex utero under experimental conditions, the trophoblast exhibits similar vascular invasion behavior. In view of this, our findings may contribute to a better understanding of trophoblast cell migration to the maternal blood supply as well as the role of the trophoblast in the establishment of the placental circulation during pregnancy.

Blood pressure variations, hemorheological determinants, and platelet aggregation in hypertensive patients with unstable angina

Plasma viscosity, fibrinogen, haematocrit and beta-thromboglobulin were assessed on venous blood samples taken within 24 hours of admission from 20 consecutive male hypertensive patients with unstable angina and 20 male hypertensive patients with stable angina, matched for clinical variables. Besides, all patients underwent automated indirect blood pressure monitoring for 24 hours, starting just after hospitalization. Despite similar average 24-hour, day-time and night-time systolic and diastolic blood pressure, hypertensive patients with unstable angina showed an increased variability of 24-hour (p <0.01) and day-time (p < 0.05) systolic and disatolic blood pressure, together with higher values of all haemorhelogical parameters (plasma viscosity, fibrinogen and haematocrit) (p < 0.01) and beta-thrombogobulin (p< 0.05), when compared with hypertensive patients with stable angina. Moreover, significant correlations between plasma viscosity and 24-hour systolic (r = 0.42, p < 0.01) and diastolic (r = 0.39, p < 0.05) blood pressure variability were shown in hypertensive patients with unstable angina. Besides, in the same patients, the haematocrit was positively correlated with 24-hour systolic blood pressure variability (r = 0.37, P < 0.05). Our data further support the relevance of rheological determinants, platelet activation and haemodynamic factors in the genesis of the high risk condition of unstable angina.

[Ischemic hepatitis: case reports and a review of the literature]

Ischemic hepatitis represents a condition in which an acute circulatory failure determines a striking elevation of both serum transaminases and total bilirubin and a prolongation of prothrombin time. Such impairment of liver function tests is due to a haemodynamic hepatocyte injury, showing focal centrilobular necrosis as the specific pathologic correlate. In this paper the authors describe four different cases of ischemic hepatitis, in which an acute derangement of liver function tests occurred as a consequence either of myocardial failure or of systemic venous congestion. Finally, the authors review all current international literature concerning the various clinical, pathologic and therapeutic features of ischemic hepatitis.

Post-implantation mouse embryos have the capability to generate and release reactive oxygen species

The capability of the mouse embryo to generate reactive oxygen species (ROS) was examined. Post-implantation embryos were carefully harvested on Day 8 of pregnancy and the production of ROS was quantified using luminol-sensitized chemiluminescence. The embryos were stimulated with either phorbol myristate acetate (PMA) or all-trans-retinal (retinal) and the reaction kinetics were followed over 10 min. ROS secretion was directly proportional to the number of embryos and was suppressed 56% by superoxide dismutase (SOD), 25% by mannitol and as little as 16% by catalase. Embryos deprived of trophoblast showed no light emission suggesting that the source of ROS generation is the trophoblast. Dihydronicotinamide adenine dinucleotide (NADH)-dependent oxidase activity in the plasma membrane of the trophoblast surface was demonstrated by cytochemical methods. The release of ROS into the extracellular medium during the phagocytic process has been related to the cytolytic effect exhibited by these molecules and, perhaps by this means, the trophoblast can play an active role in the phagocytosis of maternal cells during the process of embryo implantation.

Trophoblastic invasion of the uterine epithelium in Calomys callosus (Rodentia, Cricetidae)

Implantation sites in the uterus of the cricetid rodent Calomys callosus were examined by light and electron microscopy at several points during day 4 of pregnancy to determine the changes occurring in the trophoblast and epithelial cells during the early blastocyst-endometrial relationship, particularly the epithelial removal phase. By morning, the blastocysts had already lodged in the antimesometrial region of the uterine crypts and the embryo-maternal interaction was limited to sparse contacts between the epithelial microvilli and the trophoblast surface. A few dense and altered epithelial cells were present. Three zones could be distinguished in the stromal region. In the subepithelial area, the stromal cells showed features similar to those found in other rodents during the early decidualization process. Effective epithelial invasion by the trophoblast occurred only in the evening, although at noon, apposition and attachment phases were identifiable. During invasion, the trophoblast processes were first seen insinuating between the epithelial cells, projecting towards the basal lamina, and finally replacing these cells. The epithelial cells in contact with the invading trophoblast exhibited severe disorganization similar to that found during the process of cell death by apoptosis. The removal of such cells occurred by trophoblast phagocytosis. Once in contact with the basal lamina, the trophoblast rapidly spread out both mesometrially and antimesometrially, phagocytosing the remaining epithelial cells. Trophoblast processes were also seen penetrating the basal lamina. Given that the epithelium breached and phagocytosed by the trophoblast habitually displays degenerative characteristics, we consider the mechanisms that might be involved in epithelial cell death and in the removal of the uterine epithelium, and the participation of the trophoblast in both these events.

Invasiveness of mouse trophoblastic cells in connective tissue

Ectoplacental cones from 8-day-old mouse embryos were grafted into the dorsal subcutaneous tissue of host mice. The grafts were collected between the 3rd and 8th days after transfer and processed for morphological analysis by light and electron microscopy. Approximately 60% of the grafts formed hemorrhagic nodules in which only invasive, giant trophoblastic cells developed. These cells shared many morphological features with the trophoblastic cells involved in normal implantation. At the periphery of the nodules, trophoblastic giant cells were frequently seen growing toward the host connective tissue. The association between the trophoblast and fibrilar components of the extracellular matrix was examined. No direct association with collagen fibrils was noted; however, many areas of the surface of invasive cells were in close proximity with microfibrils of the extracellular matrix. Since only the invasive trophoblast cells exhibited such an association, a direct comparison was made with the process of trophoblast migration within the connective tissue.

[Postheparin plasmatic diamineoxidase (DAO) in chronic liver and kidney diseases (author's transl)]

PLasmatic Diamineoxidase (DAO) was studied after heparin injections i.v. (50 I.U./kg b.w.) in chronic liver and kidney diseases. The DAO increase after heparin is reduced in patients as to controls. Such a reduction may be consequence of DAO discharge in some organs determined by the deliverance of endogenous heparin.

[Clinical significance of diamine oxidase (DAO) in serous effusions of neoplastic and non neoplastic origin (author's transl)]

Diamine oxidase (DAO) levels were investigated in pleural and ascitic fluids of 142 patients suffering from neoplastic and non neoplastic diseases. While in serous effusions of non neoplastic origin or of neoplastic origin (but non containing neoplastic cells) DAO levels were similar to serum levels; in the malignant fluids containing cells of epithelial origin, DAO was very elevated and largely superior to serum values. This results seems to be of practical importance for diagnostic purposes because points out the presence of carcinomatous cells in the effusions.

[Correlation between serum values of copper, ceruloplasmin, SMAO, SDAO, in health- subjects, in pregnant women and in some pathological conditions (author's transl)]

Copper directly reactive with diethylditiocarbamate, ceruloplasmin, monoamine oxidase (SMAO) and diamine oxidase of the serum (SDAO) were studied in healthy subjects, in nine months pregnant women and in some pathological conditions. Increased values of copper were found in pregnancy. Ceruloplasminaemia was increased in hyperthyroidism, congestive hearth failure, Hodgkin's disease, and in pregnancy. Ceroluplasminaemia was strongly reduced in Wilson's disease. SMAO was increased during pregnancy. Statistical analysis showed no correlations between the variations of the data in different pathological conditions. In healthy subjects and in pregnant women, correlation was found between the values of ceruloplasmin obtained using both enzymatic and KCN methods. Statistical analysis of regression lines obtained in both groups of patients showed significative differences between slopes and elevations. It is possible that ceruloplasmin in pregnant women has different composition compared with healthy controls.

Deadtime correcton in high count rate quantitative dynamic studies with computer-assisted Anger-cameras

The use of tracers with high radioactivity in rapid dynamic quantitative studies (such as radioisotope angiocardiography), performed by the Anger-camera and data-processor, makes it possible to obtain a high counting ratemfor correct interpretation of the results of the analysis of activity/time curves in regions of interest, the authors determined, under different working conditions, the deadtimes of two Anger-cameras (Pho-gamma HP and Radicamera II), both connected to a data-processing system (Med-II). The problems inherent in this determination are analyzed and discussed. A computer program for curve correction was written and some examples of applications of it are presented, including an experiment to test the accuracy of the correction.