Strong desmin immunoreactivity in the myocardial sleeves around pulmonary veins, superior caval vein and coronary sinus supports the presumed arrhythmogenicity of these regions.

Myocardial sleeve around human pulmonary veins plays a critical role in the pathomechanism of atrial fibrillation. Besides the well-known arrhythmogenicity of these veins, there is evidence that myocardial extensions into caval veins and coronary sinus may exhibit similar features. However, studies investigating histologic properties of these structures are limited. We aimed to investigate the immunoreactivity of myocardial sleeves for intermediate filament desmin, which was reported to be more abundant in Purkinje fibers than in ventricular working cardiomyocytes. Sections of 16 human (15 adult and 1 fetal) hearts were investigated. Specimens of atrial and ventricular myocardium, sinoatrial and atrioventricular nodes, pulmonary veins, superior caval vein and coronary sinus were stained with anti-desmin monoclonal antibody. Intensity of desmin immunoreactivity in different areas was quantified by the ImageJ program. Strong desmin labeling was detected at the pacemaker and conduction system as well as in the myocardial sleeves around pulmonary veins, superior caval vein, and coronary sinus of adult hearts irrespective of sex, age, and medical history. In the fetal heart, prominent desmin labeling was observed at the sinoatrial nodal region and in the myocardial extensions around the superior caval vein. Contrarily, atrial and ventricular working myocardium exhibited low desmin immunoreactivity in both adults and fetuses. These differences were confirmed by immunohistochemical quantitative analysis. In conclusion, this study indicates that desmin is abundant in the conduction system and venous myocardial sleeves of human hearts.

Pancreaticoduodenal arterial arcades: Their dominance and variations-their potential clinical relevance.

The complex arterial system makes pancreatic interventions technically challenging for surgeons, and interventional radiologists. The arterial variants may alter tumor resecability, and cause complications in arterial embolization. International data on pancreatic blood supply are variable; therefore, we aimed to determine the frequency of variants of pancreaticoduodenal (PD) arterial arcades. Arteries of human abdominal organ complexes (50) were injected with resin mixture, and then corroded. CT scans and three-dimensional reconstructions were made; diameters of arcades were measured. Two PD arcades were found in 58%, three arcades in 30%, one arcade in three cases, four arcade in one specimen, and five arcades in two cases. In the casts with two arches the average diameter was 1.472 ± 0.432 mm on the anterior and 1.383 ± 0.343 mm on the posterior arch. Assessing the dominance of the PD arcades, the anterior arch proved to be dominant in 52% of the cases, and in 35% the posterior one by the criterion of 25% cross-section difference. It is advised to analyze the variations and dominance on a CT/MR-angiography before local chemotherapy. Furthermore, to reveal the arterial variations, a preoperative CT/MR-angiography would provide faster recuperation and better postoperative life quality. Clin. Anat. 31:544-550, 2018. © 2018 Wiley Periodicals, Inc.

Human liver regeneration in advanced cirrhosis is organized by the portal tree.

BACKGROUND & AIMS: In advanced cirrhosis new hepatocytic nodules are generated by budding of ductules in areas of parenchymal extinction. However, the vascular alterations in the areas of parenchymal extinction, the blood supply and the structure of the new hepatocytic nodules have not been analyzed in detail. METHODS: Explanted human cirrhotic livers of three different etiologies and two experimental rat models of cirrhosis were thoroughly examined. 3D reconstruction of the immunohistochemically stained serial sections and casting of human and experimental cirrhotic livers have been used to reveal the structural organization of the regenerative buds. RESULTS: In areas of parenchymal extinction the skeleton of the liver, the portal tree is preserved. The developing regenerative nodules are positioned along the portal tree and are directly supplied by terminal portal venules. The expanding nodules grow along the trunks of the portal vein. Casting of human and experimental cirrhotic livers by colored resin confirms that nodules are supplied by portal blood. The two other members of the portal triads become separated from the portal veins. CONCLUSIONS: As the structure of the hepatocyte nodules (centrally located portal vein branches, bile ducts at the periphery, hepatic veins and arteries in the connective tissue) impedes the restoration of normal liver structure, the basic architecture of hepatic tissue suffers permanent damage. We suggest that "budding" may initiate the second, irreversible stage of cirrhosis. LAY SUMMARY: Cirrhosis is the final common outcome of long lasting hepatic injury defined as the destruction of the normal liver architecture by scar tissue. In the late phase of cirrhosis stem cells-derived hepatocyte nodules appear along the branches of the portal vein suggesting an important role of this specially composed blood vessels (containing digestive end-products from the stomach and intestines) in liver regeneration. Our results contribute to a better understanding of this serious liver disease.

Extrahepatic arteries of the human liver - anatomical variants and surgical relevancies.

The purpose of our study was to investigate the anatomical variations of the extrahepatic arterial structures of the liver with particular attention to rare variations and their potential impact on liver surgery. A total of 50 human abdominal organ complexes were used to prepare corrosion casts. A multicomponent resin mixture was injected into the abdominal aorta. The portal vein was injected with a different colored resin in 16 cases. Digestion of soft tissues was achieved using cc. KOH solution at 60-65 °C. Extrahepatic arterial variations were classified according to Michels. All specimens underwent 3D volumetric CT reconstruction. Normal anatomy was seen in 42% of cases, and variants were seen in the other 58%. No Michels type VI or X variations were present; however, in 18% of cases the extrahepatic arterial anatomy did not fit into Michels' classification. We report four new extrahepatic arterial variations. In contrast to the available data, normal anatomy was found much less frequently, whereas the prevalence of unclassified arterial variations was higher. We detected four previously unknown variations. Our data may contribute to the reduction of complications during surgical and radiological interventions in the upper abdomen.

Optimal line of hepatotomy for left lateral living donor liver transplantation according to the anatomical variations of left hepatic duct system.

Multiple duct anastomoses during LLS transplantation increase the incidence of biliary complications. The optimal plane of hepatotomy that results in the least number of bile ducts at the surface was investigated according to LHD variations. Ducts of 30 human livers were injected with resin and LHD branching on 3D-CT reconstructions were analyzed. Ducts on the virtual hepatotomy surface were estimated in three splitting lines. Variations with subtypes were described. Ia (66.7%): ducts from segments (S.) II-III form a common trunk and S.IV duct joins it. Ib (10%): common trunk formed by ducts from S.II-S.III while S.IV duct joins the common hepatic duct. IIa (16.67%): S.IV duct drains into S.III duct. IIc (3.33%): S.IV duct drains into both S.II and S.III ducts. III (3.33%): trifurcation of S.II, S.III and S.IV ducts. When the virtual hepatotomy line was on the FL, there was a single duct for the anastomosis in 30% of cases but two, three, or four ducts in 53.3%, 10%, and 3.3%, respectively. Division 1 cm to the right of the FL resulted in one duct (70%), but S.IV duct injury may occur. LLS hepatotomy should not necessarily be performed along the FL. Variations must be taken into consideration to minimize the number of biliary anastomoses during liver implantation.

Collateral circulation of the rat lower limb and its significance in ischemia-reperfusion studies.

PURPOSE: Rats are the most commonly used animal model for studies of acute lower limb ischemia-reperfusion. The ischemia induced by arterial clamping may cause milder damage than the application of a tourniquet if the presence of a possible collateral system is considered. METHODS: Male Wistar rats were randomized into three groups: in group A, the muscle weight affected by ischemia was measured; in group B, the severity of muscle damage caused by the application of a tourniquet and by infrarenal aortic occlusion was examined. Blood and muscle samples were taken from group B to assess the serum necroenzyme, potassium and TNF-α levels, as well as the muscle fiber viability and for histological examinations. In group C, the identification of the lower limb collateral system was performed using corrosion casting. RESULTS: Tourniquet application affected the lower muscle mass and resulted in significantly more severe injury compared to infrarenal aortic occlusion. This difference was reflected in the serum necroenzyme, potassium and TNF-α levels. The histological examination and viability assay confirmed these findings. The corrosion casts showed several anastomoses capable of supplying the lower limb. CONCLUSION: Tourniquet application proved to be capable of inducing absolute lower limb ischemia, in contrast to infrarenal aortic ligation, where a rich collateral system is considered to help mitigate the injury.

Can the transection plane be optimized in pancreatic resections?

Purpose: According to current protocol, the separation of pancreatic head and body is performed at the level of superior mesenteric vein (SMV). Previous data indicate that the resection plane should be modified in portal annular pancreas. We presumed that the optimal line of pancreatic resections could also be different in other cases. Our aim is to simulate pancreatic resections in different planes and find the optimal resection line with the minimum number of cut vessels. Main methods: 25 abdominal vascular corrosion casts were prepared, the aorta and the portal vein were cannulated. CT scans were taken on the casts, and specific planes were reconstructed simulating different resection lines. The total amount of cross sections of vessels were calculated in the different planes. Results: In our series, the optimal plane is the SMV in 11/25, 2 cm left in 10/25, 1 cm left in 4/25, 1 cm right in 1/25 and 2 cm right in none of our cases. The group of left sided extension contain more than half of the cases. With left sided resections, the cut surface of the vessels may be lowered to even 29% compared to the SMV plane. Conclusion: Our study revealed that pancreatic resections should be extended to the left side of the SMV in more than half of our cases. Therefore, the resection plane should be determined by preoperative imaging methods. Using DICOM viewer with multiplanar reconstruction, the resection planes can be simulated in clinical practice, which would reduce the risk of postoperative bleeding.

Presence of cardiomyocytes exhibiting Purkinje-type morphology and prominent connexin45 immunoreactivity in the myocardial sleeves of cardiac veins.

BACKGROUND: Pulmonary vein (PV) myocardium is a known source of atrial fibrillation. A debated question is whether myocardial extensions into caval veins and coronary sinus (CS) have similar properties. No studies have documented specific pacemaker and/or conducting properties of human extracardiac myocardium. OBJECTIVE: The purpose of this study was to characterize the histology and immunohistochemical features of myocardial sleeves in the wall of cardiac veins. METHODS: Sections of 32 human hearts were investigated. Specimens of PVs, superior caval vein (SVC), CS, sinoatrial and atrioventricular nodes, and left ventricle were stained with Best's Carmine for selective staining of intracellular glycogen. Anti-connexin45 (Cx45)- and Cx43-specific antibodies were used to determine the conduction properties of extracardiac myocardium. RESULTS: Myocardial sleeve was found in the wall of PVs of 15 of 16 hearts, 21 of 22 SVCs, and 8 of 8 CSs. Bundles of glycogen-positive cardiomyocytes exhibiting pale cytoplasm and peripheral myofibrils were observed in the venous sleeves. Strong Cx45 and weak Cx43 labeling was detected in the extracardiac myocardium. Similar staining pattern was observed for the pacemaker and conduction system, whereas ventricular myocardium exhibited prominent Cx43 and no Cx45 immunoreactivity. CONCLUSION: Myocardial fibers of PVs, SVC, and CS exhibit morphology similar to that of Purkinje fibers and are enriched in glycogen. We provide data for the first time on prominent positive staining for Cx45 in the extracardiac myocardium, indicating its potential pacemaker and/or conducting nature.

The role of PACAP in gonadotropic hormone secretion at hypothalamic and pituitary levels.

The presence of pituitary adenylate cyclase-activating polypeptide (PACAP) and its mRNAin the three levels of the hypothalamo-hypophyseal-ovarian axis was previously demonstrated using immunohistochemistry, in situ hybridization, and reverse transcriptase polymerase chain reaction (RT-PCR). In the hypothalamus, PACAP is present in neuroendocrine effector cells and in the median eminence. In the anterior pituitary and ovary, PACAP is transiently present during the proestrous stage of the estrous cycle. In the pituitary, PACAP was observed in gonadotropes. In the ovary, PACAP was demonstrated in the granulosa cells of the preovulatory ovarian follicles. The effect of PACAP on luteinizing hormone (LH) secretion was demonstrated in in vivo and in vitro models. In our work we have studied the role of PACAP in gonadotropic hormone secretion at hypothalamic and pituitary levels. At the hypothalamic level, PACAP, administered intracerebroventricularly to female rats before the critical period of the proestrus stage, can inhibit LH release and ovulation. Its inhibiting effect is mediated through corticotropin-releasing factor (CRF) and endogenous opioids. PACAP administered to neonatal female rats delayed the onset of puberty by influencing the luteinizing hormone-releasing hormone (LHRH) neuronal system. In the pituitary gland, the release of PACAP depended on the stage of the estrous cycle and on the time of day the animals were sacrificed. On the day of proestrus, the number of PACAP-releasing cells showed a diurnal change with two peaks (in the morning and in the evening). The peak was much higher in the evening at the end of the LH surge than in the morning.

The utility of the combination of the corrosion cast method and post mortem MSCT scans.

A careful post-mortem investigation is needed to determine the cause of death of patients bearing coronary stents and to describe complications of stent implantation. The main purpose of this study was to combine post mortem methods of CT angiography and corrosion cast preparation for the visualization of coronary stenoses, coronary stents, instent restenosis, and stent occlusion. Injection-corrosion method was combined with post-mortem MSCT angiography to characterize the pathomorphological changes after stent implantation in 6 male cadaver hearts. Multi-slice computed tomography was employed to visualize the coronary artery system. For image post processing, multiplanar reconstructions, maximal intensity projections and three dimensional reconstructions were used. This study was assessing the feasibility of post mortem MSCT for intracoronary stent evaluation. We described a method for characterization of the coronary side branch stenosis caused by stent implantation. Post mortem CT imaging proved to be a feasible and highly reproducible technique for the characterization of pathological changes in the coronary system.

Cervical pulmonary herniation due to blunt chest trauma.

Traumatic lung herniation through the superior thoracic aperture rarely occurs. In this case report we present a motor vehicle accident of a 40 year old male victim with cervical lung herniation. After an enormous blunt trauma to the chest, the disrupted and lacerated lung tissue left the thoracic cavity and was pushed into the laryngeal and oral cavity. Extrathoracic post-traumatic lung herniation through the thoracic inlet and connective tissue spaces of the neck into the oral cavity is a unique complication of blunt trauma to the chest, and the post-mortem medico-legal investigations may collect more information about this phenomenon.

Post mortem introduction of corrosion cast method after coronary stent implantation.

We have firstly presented a case using post mortem corrosive method in forensic medical practice after coronary stent implantation. Occlusions, fate of side branches could be detected during the clinical diagnostic angiography, intravascular ultrasound, computed tomography; however, the forensic medical determination of cause of death, identification of complications needs a careful post-mortem investigation. The injection-corrosive method seems to be a useful assistance in the characterisation of pathomorphological changes after stent implantation. Besides the classical techniques of histology, immunohistochemistry, electron microscopic investigation we have introduced a new synthetic resin corrosion cast method. This three-dimensional corrosion cast preparation may provide new data about the actual morphological condition of the coronary vessels and a better understanding of the pathomechanisms of sudden cardiac death after percutaneous coronary intervention.

PACAP and VIP in the photoneuroendocrine system (PNES).

The presence of PACAP and VIP was demonstrated in all the four levels of the photoneuroendocrine system (PNES) with the use of immunohistochemistry (IHC), radioimmunoassay (RIA), anterograde and retrograde tracing techniques, and cell immunoblot assay (CIBA). Both peptides play a physiological role in the PNES. According to our results both PACAP and VIP are involved in the regulation of the gonadotrop hormone secretion and their inhibitory role may be mediated through the neuronal chain of the PNES.