Étude expérimentale de transplantation de cellules souches dans un modèle d'ischémie myocardique

Ischemic heart disease remains a major medical problem with high mortality rates. Beside the great efforts devoted to research worldwide and the use of numerous experimental models, an absolute understanding of myocardial infarction and tissue loss has not yet been achieved. Furthermore, the regeneration of myocardial tissue and the improvement of myocardial activity after ischemia is one of the major areas of interest in the medical (and especially cardiovascular) community. In a novel experimental rat model, the beneficial effect of mesenchymal stem cell transplantation (MSCT) in a surgically induced ischemic myocardium was documented. From a clinical perspective, this work supports the surgical administration of MSCT in the infarcted area during coronary artery bypass surgery. The regeneration of myocardial tissue and the improvement of myocardial activity after ischemia is one of the major areas of interest in cardiovascular research. We developed a novel experimental rat model and used it to examine the effect of mesenchymal stem cell transplantation (MSCT) on myocardial ischemia evaluated by SPECT-CT and immunehistochemistry. Methods and results: An open thoracotomy took place for forty adult female Wistar rats with (n = 30) or without (n = 10) surgical ligation of the left anterior descending coronary artery (LAD) in order to cause myocardial ischemia. Myocardial viability was evaluated via SPECT/CT 7 days before surgery, as well as at 7 and 14 days post-surgery. At day 0, 15 animals received homologous stem cells injected at the ischemic myocardium area. A SPECT/CT evaluation showed decreased activity of the myocardial cells in the left ventricle one week post-infarction. Regeneration of the ischemic myocardium fifteen days post-infarction was recorded only in animals subjected to stem cell transplantation. These findings were also confirmed by histology and immunohistochemical analysis, with the significantly higher expression of GATA4 and Nkx2.5. Conclusions: The positive effect of mesenchymal stem cell transplantation in the ischemic myocardium was recorded. The application of SPECT-CT allowed a clear evaluation of both the quality and quantity of the living myocardium post-infarction, leading to a new approach in the research of cardiovascular diseases. From a clinical perspective, MSCT may be beneficial when accompanied by myocardial revascularization procedures.Οι ισχαιμικές μυοκαρδιοπάθειες παραμένουν ένα μέγιστο ιατρικό πρόβλημα παγκοσμίως με υψηλό ποσοστό θνητότητας. Παρά τις πολυάριθμες προσπάθειες ερευνών και τα πολυάριθμα πειραματικά μοντέλα που έχουν αναπτυχθεί στο πέρασμα των ετών, δεν έχει γίνει ακόμα απολύτως κατανοητό το πώς εγκαθίσταται το έμφραγμα του μυοκαρδίου οδηγώντας σε απώλεια μυοκαρδιακού ιστού. Επιπλέον, η αναγέννηση του μυοκαρδίου και η βελτίωση της μυοκαρδιακής δραστηριότητας μετά την ισχαιμία είναι ένα από τα πιο σημαντικά πεδία έρευνας και ενδιαφέροντος στην παγκόσμια ιατρική (και ειδικά την καρδιαγγειακή) κοινότητα. Διαπιστώθηκε η ευεργετική δράση της έγχυσης μεσεγχυματικών βλαστοκυττάρων σε ένα πρωτότυπο πειραματικό μοντέλο με ζωικό πρότυπο τον αρουραίο με χειρουργικά εγκατεστημένη ισχαιμία του μυοκαρδίου. Από κλινική σκοπιά αυτή η μελέτη υποστηρίζει τη χειρουργική εναπόθεση μεσεγχυματικών βλαστοκυττάρων στην ισχαιμική περιοχή κατά τη διάρκεια αορτοστεφανιαίας παράκαμψης. Η αναγέννηση του μυοκαρδίου και η βελτίωση της μυοκαρδιακής δραστηριότητας μετά την ισχαιμία είναι από τα μέγιστα πεδία ενδιαφέροντος στην καρδιαγγειακή έρευνα. Αναπτύχθηκε ένα νέο πειραματικό μοντέλο με χρήση αρουραίων και χρησιμοποιήθηκε για να αξιολογηθεί η δράση των μεσεγχυματικών βλαστοκυττάρων στη μυοκαρδιακή ισχαιμία με τη χρήση σπινθηρογραφήματος SPECT-CT και ανοσοϊστοχημείας. Σε ανοιχτή θωρακοτομή υποβλήθηκαν 40 θηλυκοί ενήλικες αρουραίοι εκ των οποίων οι 30 υπέστησαν ισχαιμική περίδεση του πρόσθιου κατιόντα κλάδου της στεφανιαίας αρτηρίας ενώ οι 10 όχι. Η βιωσιμότητα του μυοκαρδίου αξιολογήθηκε με σπινθηρογράφημα SPECT-CT επτά ημέρες πριν τη χειρουργική περίδεση καθώς και επτά και δεκατέσσερις ημέρες μετεγχειρητικά. Την ημέρα μηδέν (ημέρα χειρουργείου) τα 15 ζώα έλαβαν μεσεγχυματικά βλαστοκύτταρα με άμεση έγχυση διεγχειρητικά στο ισχαιμικό πεδίο που είχε εγκατασταθεί στην αριστερή κοιλία της καρδιάς. Η ανάλυση του σπινθηρογραφήματος SPECT-CT έδειξε μειωμένη δραστηριότητα των μυοκαρδιακών κυττάρων στην αριστερή κοιλία μια εβδομάδα μετά την πρόκληση ισχαιμίας. Η αναγέννηση του ισχαιμικού μυοκαρδίου δεκαπέντε ημέρες μετά το χειρουργείο διαπιστώθηκε μόνο στα ζώα που έλαβαν τα βλαστοκύτταρα. Αυτά τα αποτελέσματα επιβεβαιώθηκαν με ιστολογική και ανοσοϊστοχημική ανάλυση με σημαντικά μεγαλύτερη έκφραση των GATA4 και Nkx2.5. Συμπερασματικά η θετική επίδραση της μεταμόσχευσης μεσεγχυματικών βλαστοκυττάρων στο ισχαιμικό μυοκάρδιο καταγράφηκε αδιαμφισβήτητα. Η χρήση σπινθηρογραφήματος SPECT-CT επέτρεψε μια ξεκάθαρη αξιολόγηση τόσο ποιοτική όσο και ποσοτική του ζωντανού μυοκαρδιακού ιστού μετά την πρόκληση ισχαιμίας οδηγώντας σε μια νέα προσέγγιση της έρευνας των καρδιαγγειακών παθήσεων. Από κλινικής πλευράς, η χρήση των μεσεγχυματικών βλαστοκυττάρων μπορεί να είναι ευεργετική όταν συνδυάζεται με τεχνικές επαναιμάτωσης του μυοκαρδίου

Recurrent Struma Ovarii Presented with High Levels of Thyroglobulin

Struma ovarii are rare ovarian tumors, of monodermal germ cell origin, containing predominantly thyroid tissue. They are typically benign unilateral pelvic masses. Among the rare cases of malignancy, the most common histological type is that of the papillary carcinoma. A definite preoperative diagnosis of these tumors is difficult to achieve since most imaging findings are generally nonspecific. A rare exception is the case of synchronous abnormal thyroid blood tests where an ovarian teratoma should be highly suspected, especially when no pathology of the thyroid gland coexists. Surgical excision is the mainstay of treatment. Taking into account that struma ovarii are mainly encountered in patients of a childbearing age, a conservative surgical approach is a reasonable option. We present the case of a 56-year-old woman who was diagnosed with both a primary and recurrent struma ovarii while investigating the incidental finding of elevated blood laboratory levels of the thyroglobulin (Tg)

Rare Case of Hepatic Endometriosis as an Incidental Finding: Difficult Diagnosis of a Diagnostic Dilemma

Endometriosis is the abnormal existence of functional uterine mucosal tissue outside the uterus. It is a usual disorder of women in reproductive age which is mainly located in the female genital tract. Hepatic endometriosis is one of the rarest disorders characterised by the presence of ectopic endometrium in the liver. It is often described as cystic mass with or without solid component. Preoperative diagnosis is difficult via cross-sectional imaging and histopathologic evaluation remains the gold standard for diagnosis. We report an asymptomatic 40-year-old female with a large cystic mass involving the left hepatic lobe. She underwent laparoscopic removal of the cyst. The diagnosis of hepatic endometriosis was established by the histopathological analysis of the surgical specimen

Mesenchymal Stem Cell Transplantation Has a Regenerative Effect in Ischemic Myocardium: An Experimental Rat Model Evaluated by SPECT-CT Assessment

Translational perspective: Ischemic heart disease remains a major medical problem with high mortality rates. Beside the great efforts devoted to research worldwide and the use of numerous experimental models, an absolute understanding of myocardial infarction and tissue loss has not yet been achieved. Furthermore, the regeneration of myocardial tissue and the improvement of myocardial activity after ischemia is one of the major areas of interest in the medical (and especially cardiovascular) community. In a novel experimental rat model, the beneficial effect of mesenchymal stem cell transplantation (MSCT) in a surgically induced ischemic myocardium was documented. From a clinical perspective, this work supports the surgical administration of MSCT in the infarcted area during coronary artery bypass surgery. Aims: The regeneration of myocardial tissue and the improvement of myocardial activity after ischemia is one of the major areas of interest in cardiovascular research. We developed a novel experimental rat model and used it to examine the effect of mesenchymal stem cell transplantation (MSCT) on myocardial ischemia evaluated by SPECT-CT and immunohistochemistry. Methods and results: An open thoracotomy took place for forty adult female Wistar rats with (n = 30) or without (n = 10) surgical ligation of the left anterior descending coronary artery (LAD) in order to cause myocardial ischemia. Myocardial viability was evaluated via SPECT/CT 7 days before surgery, as well as at 7 and 14 days post-surgery. At day 0, 15 animals received homologous stem cells injected at the ischemic myocardium area. A SPECT/CT evaluation showed decreased activity of the myocardial cells in the left ventricle one week post-infarction. Regeneration of the ischemic myocardium fifteen days post-infarction was recorded only in animals subjected to stem cell transplantation. These findings were also confirmed by histology and immunohistochemical analysis, with the significantly higher expression of GATA4 and Nkx2.5. Conclusions: The positive effect of mesenchymal stem cell transplantation in the ischemic myocardium was recorded. The application of SPECT-CT allowed a clear evaluation of both the quality and quantity of the living myocardium post-infarction, leading to a new approach in the research of cardiovascular diseases. From a clinical perspective, MSCT may be beneficial when accompanied by myocardial revascularization procedures

Hippocampal Spatial Position Evaluation on MRI for Research and Clinical Practice

<div><p>In clinical practice as well as in many volumetric studies we use different reorientations of the brain position towards x and y axis on the magnetic resonance imaging (MRI) scans. In order to find out whether it has an overall effect on the resulting 2D data, manual hippocampal area measurements and rotation variability of the brain (in two reoriented axes) and the skull were performed in 23 Alzheimer's disease patients and 31 healthy controls. After the MRI scanning, <i>native brain scans</i> (nat) were reoriented into the two different artificial planes (<i>anterior commissure – posterior commissure</i> axis (AC-PC) and <i>hippocampal horizontal long axis</i> (hipp)). Hippocampal area and temporal horn of the lateral ventricle was measured manually using freeware Image J program. We found that 1) hippocampal area of nat images is larger compared to hipp images, area of the nat images is equal to the AC-PC images and area of the hipp images is smaller compared to AC-PC images, 2) hippocampal area together with the area of the temporal horn for nat images is larger compared to hipp images, area of the hipp images is smaller compared to the AC-PC images and area of the nat images is smaller compared to the AC-PC images. The conclusion is that the measured area of the hippocampus in the native MRI is almost the same as the area of MRI reoriented only into the AC-PC axis. Therefore, when performing 2D area studies of the hippocampus or in the clinical practice we recommend usage of not-reoriented MRI images or to reorient them into the AC-PC axis. Surprising finding was that rotation of both AC-PC and hipp line towards x-axis among patients varies up to 35° and the same is true for the skull rotation so that it is not only a matter of the brain position.</p></div

Effects of the brains rotations on the area measurements of the hippocampus on the MRI.

<p>Three groups are presented on the x-axis – nat (as the unaltered MRI scans were exported for 2D area analysis), hipp (x-axis is parallel to the long axis of the hippocampus) and AC-PC (x axis is parallel to the line connecting <i>anterior</i> and <i>posterior commissure</i>). On the y-axis, 2D area values of the hippocampi in mm² are presented. Results are presented as median ± min-max.</p

a,b,c Examples of the sagittal view of the right hippocampus on the MRI in one native and two reoriented axis.

<p>MRI sections were selected according to the best visibility of the of the hippocampus on the sagittal sections (its long or dorsoventral axis), a) position of the hippocampus on the “native” MRI scan, b) reorientation of the “native” MRI scan into the hipo-axis axis (where long axis of the hippocampus is parallel to the horizontal axis), c) reorientation of the “native” MRI scan into the CA-CP. White lines represent long axis of the hippocampus.</p

Relationship between brain and skull rotation.

<p>The brain rotation in AC-PC axis and the skull rotation (Frankfurt plane) exhibit a similar degree of variability (- counter clockwise or dorsal). AC-PC axis, Mean  = -8.57°, SE = 9.2°. Frankfurt (auriculo-orbital) plane, Mean  = −16.3°, SE = 8.02°.</p

Brain rotation variability of AC-PC vs nat on MRI.

<p>The extent of the brain rotation in AC-PC vs nat is shown in decimal degrees on x-axis (– counter clockwise and + clockwise rotation) (p<0.05).</p