Pulmonary coin lesion caused by Dirofilaria immitis - a report of two cases with a minireview of the literature.

Dirofilariasis is a rare zoonosis, transmitted from infested dogs or other carnivorous animals to humans via mosquitoes. Two male patients with a solitary, peripheral, well-defined, coin-like pulmonary lesion in the right upper lobe were presented. Rapid enlargement of the lesion within a few months suggested malignancy, resulting in surgical removal. Microscopic examination of the resected lung revealed necrotic circumscribed lesions with embolized parasites in the vessels. Both parasites were females of the species Dirofilaria immitis. They represent the first reported cases of pulmonary dirofilariasis in Slovenia. Awareness of this entity is important in the differential diagnosis of pulmonary coin lesions.

Multiorgan failure with fatal outcome after stem cell tourism.

BACKGROUND: Unproven stem cell treatments may involve serious health, personal, and financial considerations. Due to worldwide spread, illegal stem cell therapies have become a major public health problem. We have already witnessed numerous reports in the mass media of severe and occasionally even fatal outcomes after such therapies. However, there are only few scientifically documented cases in which the causality between stem cell therapy and side effects cannot be refuted. CASE PRESENTATION: Here we present a case report of a 48-year-old patient with serious side effects, including disseminated skin ulcers, hepatitis, and cardiomyopathy, with eventual fatal outcome following unproven stem cell treatment. CONCLUSIONS: The case of the patient presented here draws attention to the worst possible outcome of stem cell tourism. To effectively combat this issue, professionals and patients should be empowered with the right knowledge on possible side effects.

Pseudoangiomatous stromal hyperplasia with multinucleated stromal giant cells is neither exceptional in gynecomastia nor characteristic of neurofibromatosis type 1.

Six cases of gynecomastia with pseudoangiomatous stromal hyperplasia (PASH) and multinucleated stromal giant cells (MSGC) associated with neurofibromatosis type 1 (NF1) have been reported, and finding MSGC within PASH in gynecomastia has been suggested as being a characteristic of NF1. The frequency of PASH with MSGC in gynecomastia and its specificity for NF1 have not, however, been systematically studied. A total of 337 gynecomastia specimens from 215 patients, aged from 8 to 78 years (median, 22 years) were reevaluated for the presence of PASH with MSGC. Breast tissue samples of 25 patients were analyzed for the presence of an NF1 gene mutation using next generation sequencing. Rare MSGC, usually in the background of PASH, were noted at least unilaterally in 27 (13 %) patients; and prominent MSGC, always in the background of PASH, were noted in 8 (4 %) patients. The NF1 gene was mutated in only 1 (an 8-year-old boy with known NF1 and prominent MSGC) of the 25 tested patients, including 6 patients with prominent MSGC and 19 patients with rare MSGC. MSGC, usually in the background of PASH, are not characteristic of NF1.

miR-1, miR-133a/b, and miR-208a in human fetal hearts correlate to the apoptotic and proliferation markers.

The heart is the first organ to function in the developing embryo. MicroRNAs (miRNAs) are small non-coding RNAs involved in the translational regulation of gene expression, which is beside transcriptional regulation crucial for the morphologic development of muscle tissue. The aim of our study was to test the hypothesis that the expression of miR-1, miR-133a/b, and miR-208a correlates with gestational age as well as with an apoptotic and proliferative index in the developing human heart. Our study included normal heart tissue samples obtained at autopsy from 46 fetuses, 12 children, and 15 adults. Proliferation and apoptosis were measured by the immunohistochemical detection of Ki67 and cleaved-CK18. Expression of miR-1, miR-133a, miR-133b, and miR-208a was measured using real-time PCR. We found a similar level of expression of miR-133a/b in fetal and children hearts that was different from the levels in healthy adults. We also found a correlation between a miR-208a expression to the gestational age of fetuses. We observed an inverse correlation between Ki67 expression and gestational age. Expression of Ki67 was positively correlated to the expression of miR-208a and miR-1, but inversely correlated to the expression of miR-133a/b. Expression of cleaved-CK18 was also inversely correlated to the expression of miR-133a/b. Our results showed a general decrease in the expression of miR-1 and an increase of miR-133a/b with increasing gestational age. We also found a general decrease in the expression of miR-208a, mimicking the expression of its host gene. Our results also suggest the involvement of miR-208a and miR-1 in the proliferation as well as anti-proliferative and anti-apoptotic roles of miR-133a/b.

Mediastinal teratoma with hydrops fetalis in a newborn and development of chronic respiratory insufficiency.

BACKGROUND: Mediastinal fetal teratoma can be detected as a mass in the chest during a routine prenatal ultra-sound screening. Because of the pressure on mediastinal structures it can be the cause of non-immune hydrops fetalis and polyhydramnion. The development of hydrops fetalis leads to fetal death or premature delivery in most reported cases. Early surgical removal is important, but, the result of treatment depends on the stage of development of mediastinal organs and complications in the postoperative period. CASE REPORT: A 31-year-old gravida carrying twins, with spontaneous membrane rupture at 32 weeks gestation underwent urgent caesarean section after antenatal ultrasound revealed severe polyhydramnion and hydrops fetalis in geminus A. The child was intubated immediately after birth due to severe respiratory distress. Ultrasound and X-ray revealed a tumour mass in the right hemithorax. Tumour resection was performed at the age of 7 days. Histology examination revealed an encapsulated immature teratoma. The postoperative course was complicated with respiratory insufficiency which turned into chronic at the age of eight months. CONCLUSION: This is the fifth reported child with fetal mediastinal teratoma and severe hydrops fetalis that survived the neonatal period. Additional diagnostic search revealed abnormal course of both pulmonary arteries, which was probably one of the main causes of respiratory insufficiency.

Apoptosis in the developing human heart resembles apoptosis in epithelial tissues.

It is widely accepted that apoptosis plays an important role in the development of the heart as well as in different heart diseases. Despite extensive research efforts, many issues regarding apoptosis in the heart remain unsolved, including the detection of apoptotic cardiomyocytes, their morphological features, the mechanisms of their removal and the clinical significance of apoptosis in the heart. It has been suggested that fetal cardiomyocytes resemble epithelial tissues. To test this hypothesis, we analyzed the expression of an epithelial marker cytokeratin 18 (CK18) and caspase-cleaved-CK18, recognized by antibody M30, as well as the expression of cleaved caspase-3 and desmosomal and classical cadherins, major components of desmosomes and adherens junctions in fetal hearts in comparison to infant and adult human hearts. We found that, in fetal hearts, cardiomyocytes expressed CK18 and that apoptotic cardiomyocytes expressed caspase-cleaved CK18, being recognized by antibody M30. Furthermore, desmosomal and classical cadherins exhibited a membraneous reaction similar to epithelial tissues. In adults and children after the age of 6 months, cadherins were localized in the intercalated disks, cardiomyocytes lost CK18 expression and apoptotic cardiomyocytes were no longer recognized by M30. We conclude that apoptosis in the developing human heart resembles apoptosis in epithelial tissues, exhibiting different characteristics than in the adult human heart.

Cyclooxygenase in normal human tissues--is COX-1 really a constitutive isoform, and COX-2 an inducible isoform?

Cyclooxygenase (COX) is a key enzyme in prostanoid synthesis. It exists in two isoforms, COX-1 and COX-2. COX-1 is referred to as a 'constitutive isoform', and is considered to be expressed in most tissues under basal conditions. In contrast, COX-2 is referred to as an 'inducible isoform', which is believed to be undetectable in most normal tissues, but can be up-regulated during various conditions, many of them pathological. Even though the role of COX in homeostasis and disease in now well appreciated, controversial information is available concerning the distribution of COX isoforms in normal human tissues. There is mounting evidence that it is much more complex than generally believed. Our aim was therefore to analyse the expression and distribution of COX isoforms in normal human tissues, using immunohistochemistry, Western blotting and real-time RT-PCR. Autopsy samples from 20 healthy trauma victims and samples from 48 biopsy surgical specimens were included. COX-1 was found in blood vessels, interstitial cells, smooth muscle cells, platelets and mesothelial cells. In contrast, COX-2 was found predominantly in the parenchymal cells of many tissues, with few exceptions, for example the heart. Our results confirm the hypothesis that the distribution of COX isoforms in healthy tissues is much more complex than generally believed. This and previous studies indicate that both isoforms, not only COX-1, are present in many normal human tissues, and that both isoforms, not only COX-2, are up-regulated in various pathological conditions. We may have to revise the concept of 'constitutive' and 'inducible' COX isoforms.

Expression of cyclooxygenase-1 and cyclooxygenase-2 in the normal human heart and in myocardial infarction.

INTRODUCTION: Cyclooxygenase is a key enzyme in prostanoid synthesis. It exists in two isoforms: cyclooxygenase-1 (COX-1), which is constitutively expressed in cells and tissues maintaining normal homeostasis, and cyclooxygenase-2 (COX-2), which is normally not present in most cells, but can be induced by various stimuli. Little is known about the significance of COX isoforms in the normal human heart and in myocardial infarction (MI). Thus, we aimed to investigate the immunohistochemical expression of COX-1 and COX-2 in the normal human heart and in MI. METHODS: Our study included autopsy samples of heart tissue from 15 healthy individuals who died in accidents, and from 40 patients with MI who died few hours to a month after the onset of symptoms. Immunohistochemistry was performed by a sensitive peroxidase-streptavidin method on formalin fixed, paraffin-embedded tissue, using monoclonal antibodies against COX-1 and COX-2. RESULTS: In normal hearts, COX-1 was found in endothelial and smooth muscle cells of blood vessels and in endothelial cells of the endocardium. In MI, it was expressed in inflammatory cells, as well as in myofibroblasts and capillaries of granulation and fibrous tissue. COX-2 was either not present or it was present in occasional myocytes in the normal hearts. In MI, its expression was induced in cardiomyocytes as well as in interstitial inflammatory cells, and in capillaries and myofibroblasts in granulation tissue. CONCLUSIONS: Our results suggest that COX-1 is associated with normal homeostasis in the heart, whereas COX-2 probably mediates inflammatory reaction in MI. It appears that both COX-1 and COX-2 are associated with the healing processes and scar formation after MI.