Increased Infiltration of Extra-Cardiac Cells in Myxomatous Valve Disease.

Mutations in the actin-binding gene Filamin-A have been linked to non-syndromic myxomatous valvular dystrophy and associated mitral valve prolapse. Previous studies by our group traced the adult valve defects back to developmental errors in valve interstitial cell-mediated extracellular matrix remodeling during fetal valve gestation. Mice deficient in Filamin-A exhibit enlarged mitral leaflets at E17.5, and subsequent progression to a myxomatous phenotype is observed by two months. For this study, we sought to define mechanisms that contribute to myxomatous degeneration in the adult Filamin-A-deficient mouse. In vivo experiments demonstrate increased infiltration of hematopoietic-derived cells and macrophages in adolescent Filamin-A conditional knockout mice. Concurrent with this infiltration of hematopoietic cells, we show an increase in Erk activity, which localizes to regions of MMP2 expression. Additionally, increases in cell proliferation are observed at two months, when hematopoietic cell engraftment and signaling are pronounced. Similar changes are observed in human myxomatous mitral valve tissue, suggesting that infiltration of hematopoietic-derived cells and/or increased Erk signaling may contribute to myxomatous valvular dystrophy. Consequently, immune cell targeting and/or suppression of pErk activities may represent an effective therapeutic option for mitral valve prolapse patients.

Bleomycin delivery by osmotic minipump: similarity to human scleroderma interstitial lung disease.

The interstitial lung diseases (ILD) include a large number of chronic, progressive, irreversible respiratory disorders involving pulmonary fibrosis, the most common of which are idiopathic pulmonary fibrosis and scleroderma lung disease (SSc ILD). Because bleomycin causes lung fibrosis when used in cancer chemotherapy, it is used to model human ILD in rodents. In most studies, bleomycin has been delivered directly into the lung by intratracheal or intraoral administration. Here we have compared the effects in mice of bleomycin delivered directly into the lungs (direct model) or systemically using osmotic minipumps (pump model) to determine which more closely resembles human ILD. The pump model is more similar to human SSc ILD in that: 1) lung injury/fibrosis is limited to the subpleural portion of the lung in the pump model and in SSc ILD, whereas the entire lung is affected in the direct model; 2) conversely, there is massive inflammation throughout the lung in the direct model, whereas inflammation is limited in the pump model and in SSc ILD; 3) hypertrophic type II alveolar epithelial cells are present at high levels in SSc ILD and in the pump model but not in the direct model; and 4) lung fibrosis is accompanied by dermal fibrosis. The pump model is also move convenient and humane than the direct model because there is less weight loss and mortality.

Changing topographic Hox expression in blood vessels results in regionally distinct vessel wall remodeling.

The distinct topographic Hox expression patterns observed in vascular smooth muscle cells (VSMCs) of the adult cardiovascular system suggest that these transcriptional regulators are critical for maintaining region-specific physiological properties of blood vessels. To test this proposition, we expanded the vascular Hoxc11 expression domain normally restricted to the lower limbs by utilizing an innovative integrated tetracycline regulatory system and Transgelin promoter elements to induce Hoxc11 expression universally in VSMCs of transgenic mice. Ectopic Hoxc11 expression in carotid arteries, aortic arch and descending aorta resulted in drastic vessel wall remodeling involving elastic laminae fragmentation, medial smooth muscle cell loss, and intimal lesion formation. None of these alterations were observed upon induction of Hoxc11 transgene expression in the femoral artery, i.e. the natural Hoxc11 activity domain, although this vessel was greatly enlarged, comparable to the topographically restricted vascular changes seen in Hoxc11(-/-) mice. To begin defining Hoxc11-controlled pathways of vascular remodeling, we performed immunolabeling studies in conjunction with co-transfection and chromatin immunoprecipitation (ChIP) assays using mouse vascular smooth muscle (MOVAS) cells. The results suggest direct transcriptional control of two members of the matrix metalloproteinase (Mmp) family, including Mmp2 and Mmp9 that are known as key players in the inception and progression of vascular remodeling events. In summary, the severe vascular abnormalities resulting from the induced dysregulated expression of a Hox gene with regional vascular patterning functions suggest that proper Hox function and regulation is critical for maintaining vascular functional integrity.

Atrioventricular valve development: new perspectives on an old theme.

Atrioventricular valve development commences with an EMT event whereby endocardial cells transform into mesenchyme. The molecular events that induce this phenotypic change are well understood and include many growth factors, signaling components, and transcription factors. Besides their clear importance in valve development, the role of these transformed mesenchyme and the function they serve in the developing prevalve leaflets is less understood. Indeed, we know that these cells migrate, but how and why do they migrate? We also know that they undergo a transition to a mature, committed cell, largely defined as an interstitial fibroblast due to their ability to secrete various matrix components including collagen type I. However, we have yet to uncover mechanisms by which the matrix is synthesized, how it is secreted, and how it is organized. As valve disease is largely characterized by altered cell number, cell activation, and matrix disorganization, answering questions of how the valves are built will likely provide us with information of real clinical relevance. Although expression profiling and descriptive or correlative analyses are insightful, to advance the field, we must now move past the simplicity of these assays and ask fundamental, mechanistic based questions aimed at understanding how valves are "built". Herein we review current understandings of atrioventricular valve development and present what is known and what isn't known. In most cases, basic, biological questions and hypotheses that were presented decades ago on valve development still are yet to be answered but likely hold keys to uncovering new discoveries with relevance to both embryonic development and the developmental basis of adult heart valve diseases. Thus, the goal of this review is to remind us of these questions and provide new perspectives on an old theme of valve development.

Recruitment of bone marrow-derived valve interstitial cells is a normal homeostatic process.

Advances in understanding of the maintenance of the cardiac valves during normal cardiac function and response to injury have led to several novel findings, including that there is contribution of extra-cardiac cells to the major cellular population of the valve: the valve interstitial cell (VIC). While suggested to occur in human heart studies, we have been able to experimentally demonstrate, using a mouse model, that cells of bone marrow hematopoietic stem cell origin engraft into the valves and synthesize collagen type I. Based on these initial findings, we sought to further characterize this cell population in terms of its similarity to VICs and begin to elucidate its contribution to valve homeostasis. To accomplish this, chimeric mice whose bone marrow was repopulated with enhanced green fluorescent protein (EGFP) expressing total nucleated bone marrow cells were used to establish a profile of EGFP(+) valve cells in terms of their expression of hematopoietic antigens, progenitor markers, fibroblast- and myofibroblast-related molecules, as well as their distribution within the valves. Using this profile, we show that normal (non-irradiated, non-transplanted) mice have BM-derived cell populations that exhibit identical morphology and phenotype to those observed in transplanted mice. Collectively, our findings establish that the engraftment of bone marrow-derived cells occurs as part of normal valve homeostasis. Further, our efforts demonstrate that the use of myeloablative irradiation, which is commonly employed in studies involving bone marrow transplantation, does not elicit changes in the bone marrow-derived VIC phenotype in recipient mice.

Beneficial effects of theophylline infusions in surgical patients with intra-abdominal hypertension.

BACKGROUND: Intra-abdominal hypertension (IAH) can cause high mortality. Recently, we found that IAH was associated with increased serum levels of adenosine and interleukin 10. Our present "hypothesis-generated study" was based on the above mentioned results. MATERIALS AND METHODS: In this uncontrolled clinical trial, a total of 78 patients with IAH were enrolled representing a 13-20 mmHg range of intra-abdominal pressure (IAP). Patients requiring surgical abdominal decompression were excluded. Patients were treated with the following protocols: standard supportive therapy (ST, n = 38) or ST plus infusion with the adenosine receptor antagonist theophylline (T, n = 40). Over the 5-day measurement period, IAP was monitored continuously and serum adenosine concentration and other clinical and laboratory measurements were monitored daily. Mortality was followed for the first 30 days following the diagnosis of IAH. RESULTS: Mortality of ST patients was 55%, which is compatible to other studies. Serum adenosine concentration was found to be directly proportional to IAP. Of the 40 patients receiving T treatment, survival was 100%. An increased survival related to theophylline infusion correlated with improving serum concentrations of IL-10, urea, and creatinine, as well as 24-h urine output, fluid balance, mean arterial pressure, and O(2)Sat. CONCLUSIONS: Adenosine receptor antagonism with T following IAH diagnosis resulted in markedly reduced mortality in patients with moderated IAH (<20 mmHg). Theophylline-associated mortality reduction may be related to improved renal perfusion and improved MAP, presumably caused by adenosine receptor blockade. Because this study was not a randomized controlled study, these compelling observations require further multicentric clinical confirmation.

Tissue spheroid fusion-based in vitro screening assays for analysis of tissue maturation.

Organ printing or computer-aided robotic layer-by-layer additive biofabrication of thick three-dimensional (3D) living tissue constructs employing self-assembling tissue spheroids is a rapidly evolving alternative to classic solid scaffold-based approaches in tissue engineering. However, the absence of effective methods of accelerated tissue maturation immediately after bioprinting is the main technological imperative and potential impediment for further progress in the development of this emerging organ printing technology. Identification of the optimal combination of factors and conditions that accelerate tissue maturation ('maturogenic' factors) is an essential and necessary endeavour. Screening of maturogenic factors would be most efficiently accomplished using high-throughput quantitative in vitro tissue maturation assays. We have recently reviewed the formation of solid scaffold-free tissue constructs through the fusion of bioprinted tissue spheroids that have measurable material properties. We hypothesize that the fusion kinetics of these tissue spheroids will provide an efficacious in vitro assay of the level of tissue maturation. We report here the results of experimental testing of two simple quantitative tissue spheroid fusion-based in vitro high-throughput screening assays of tissue maturation: (a) a tissue spheroid envelopment assay; and (b) a tissue spheroid fusion kinetics assay.

Increased serum adenosine and interleukin 10 levels as new laboratory markers of increased intra-abdominal pressure.

BACKGROUND: Increased intra-abdominal pressure (IAP), intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are severe complications of surgical interventions with a high rate of mortality. The technique of IAP measurement is accurate, precise, reproducible and cost-effective. However, laboratory measures for monitoring of IAH have not been defined. We investigated the linkage between the serum levels of adenosine and interleukin 10 (IL-10) with IAP. METHODS: The sera of 25 surgical patients with IAP <12 mmHg and of 45 surgical patients with IAP >12 mmHg were tested. Serum adenosine concentration was measured by HPLC. Serum IL-1ß, IL-2, IL-4, IL-10, TNFα, IFNγ and IL-10 were determined by enzyme linked immunosorbent assay (ELISA). CRP was measured by nephelometry. RESULTS: Significant correlations of IAP were found only with serum levels of adenosine and IL-10. In the sera of patients with IAP >12 mmHg, the levels of both adenosine (1.61 versus 0.06 µM, p < 0.01) and IL-10 (63.23 versus 27.27 pg/ml, p < 0.01) were significantly higher than those in patients with IAP <12 mmHg. Moreover, significant correlations were found between individual patient IAP-adenosine values (r = 0.766, p < 0.001), IAP-IL-10 values (r = 0.792, p < 0.001) and adenosine-IL-10 values (r = 0.888, p < 0.001). A direct linear correlation between IAP-adenosine and IAP-10 values was only observed with IAP >15 (Grade II-IV). CONCLUSION: We report associations between IAP and the serum adenosine and IL-10 levels providing new tools for the laboratory monitoring of IAH as well as further understanding of the pathomechanisms contributing to ACS.

The abdominal compartment syndrome (ACS) in general surgery.

BACKGROUND: The abdominal compartment syndrome is a life threatening clinical entity which can develop within the first 12 hours of intensive care unit admission in high-risk surgical patients. The aim of this paper is to show the definitions, ethiology, pathophysiology, diagnosis and treatment of this serious, not only surgical problem. METHODOLOGY: The mortality due to the abdominal compartment syndrome is extremely high (38-71%). It can be defined as adverse physiologic consequences that occur as a result of an acute increase in the intraabdominal pressure. The most common causes are retroperitoneal haemorrhage, visceral oedema, pancreatitis, bowel obstruction, tense ascites, peritonitis, tumor. The mostly affected systems are cardiovascular, pulmonary, renal, central nervous systems and splanchnic organs. The gold standard diagnostic method is the continuous intra-abdominal pressure monitoring. The treatment consists of adequate fluid resuscitation and surgical decompression. RESULTS: We show three typical short case reports treated by the above mentioned theories. CONCLUSIONS: Intraabdominal hypertension and abdominal compartment syndrome are frequent clinical findings among acute general surgical patients. Patients with comparable demographics and acute severity of illness are more likely to die if intraabdominal hypertension or abdominal compartment syndrome is present. We conclude that the early recognition and surgical decompression is urgent.

[Stromal tumor of the stomach causing life-threatening arterial bleeding]. / A gyomor életveszélyes arteriás vérzést okozó stromalis tumora.

Stromal tumors of the gastrointestinal tract are rare mesenchymal neoplasms. The majority of them are appearing in the stomach: their quite common first manifestation is bleeding. The authors report a case of polypoid gastric GIST causing severe bleeding which needed urgent surgical intervention and partial resection of the stomach. Although histological analysis of the tumor revealed low proliferation rate, the urgent operation did not result in a complete eradication of the neoplasm, thereby our patient needs further follow-up and treatment.

[The abdominal compartment syndrome (ACS) in general surgery]. / Abdominális kompartment szindróma (ACS) az általános sebészetben.

Mortality due to the abdominal compartment syndrome is extremely high (38-71%). It may be defined as adverse physiologic consequences that occur as a result of an acute increase in the intraabdominal pressure. The most common causes of abdominal compartment syndrome are retroperitoneal haemorrhage, visceral oedema, pancreatitis, bowel distension, venous mesenterial obstruction, tense ascites, peritonitis, tumor. The mostly affected organ systems include cardiovascular, pulmonary, renal, central nervous and splanchnic. The diagnosis depends on the recognition of the clinical syndrome followed by an objective measurement of intraabdominal pressure, preferably that of the urinary bladder. The treatment consist of adequate fluid resuscitation and surgical decompression when necessary.

Impact of heterophil granulocyte depletion caused by 5-fluorouracil on infectious bursal disease virus infection in specific pathogen free chickens.

The purpose of this study was to investigate the influence of the cytostatic drug, 5-fluorouracil (5-FU), which causes depletion of heterophil granulocytes, on clinical symptoms and histological lesions during the progress of infectious bursal disease virus (IBDV) infection in chickens. The aim was to disclose the mechanism behind the clinical disease symptoms. Three groups of specific pathogen free chickens were used for the experiment. Chickens in groups 1 and 3 were pretreated with 5-FU, while chickens in group 2 were treated with a placebo. After 5 days, the chickens in groups 2 and 3 were inoculated with the classical IBDV strain F52/70. Bursae of Fabricius were sampled at fixed intervals, and the progress of the infection was monitored by various histological techniques and reverse transcriptase-polymerase chain reaction (RT-PCR). We found correlation between histological observations and RT-PCR results. In the 5-FU pretreated chickens, IBDV caused only mild clinical symptoms, even though histological alterations similar to alterations caused by IBDV were still observed. The 5-FU pretreatment resulted in severe heterophil granulocyte depletion by days 2 and 3 after infection (post inoculation) and increased numbers of bursal secretory dendritic cells in the medulla of the follicles. IBDV infection seemed to induce fusion of secretory dendritic cells, resulting in formation of multinucleated giant cells, loaded with apoptotic B cells and virus particles associated with granules of bursal secretory dendritic cells. Our results indicate that the heterophil granulocytes together with the bursal secretory dendritic cells contribute to the outbreak and/or progress of clinical symptoms.

[Comparative hematologic and immunologic studies of patients with splenectomy and spleen autotransplantation]. / Splenectomizált és lép autotranszplantált betegek összehasonlító haematologiai és immunologiai vizsgálatai.

We compared changes in haematological and immunological parameters of patients with splenectomy (n=24), splenectomy plus spleen autotransplantation (n=12) and healthy controls (n=23). In the autotransplantation group pieces of the removed spleen were placed into the omentum with good visible circulation. Significant alterations in the hematological status and in some immunological parameters were observed in both groups of patients who were operated on compared to those in the control group. There was no difference, however, between the results of the two groups of operated patients. Therefore, we emphasize the importance of vaccination in patients with spleen autotransplantation in order to prevent potential sepsis. In addition, we recommend the possible further use of spleen autotransplantation.

[Our experiences during laparoscopic giant paraesophageal hernia repair (1993-2004)]. / Oriás rekeszsérvek laparoszkópos mutétei során szerzett tapasztalataink (1993-2004).

INTRODUCTION: Following both open and laparoscopic surgery for large hiatus hernias the recurrence rate is high. During the last decade we found that the correct indication and operation technique at primary operation should be prophylactic against recurrent hiatus hernia and postoperative dysphagia. MATERIAL AND METHOD: Between 1993 and 2004 more than 350 antireflux procedures were performed in our department. In 35 patients direct crural reconstructions and onlay-mesh implantation was necessary because of extremely large hiatus hernias. The onlay-mesh implantation and tension-free hiatus reconstruction beside correct calibration of the lower esophageal sphincter (LES) decreases the chance of recurrence and postoperative dysphagia. RESULTS: In the early period there were five recurrent hernias due to crural reconstruction with absorbable sutures, weak intracorporally knotted crural sutures and extremely large hiatus hernia. During laparoscopic reoperations reconstructions with onlay mesh implantation were performed successfully. CONCLUSION: The mesh implantation with correct indication and intraoperatively calibrated wrap decrease recurrence and postoperative dysphagia. Laparoscopic reoperation is a safe procedure with good results in trained hands.

[Difficulties in the treatment of polycystic liver]. / A polycystás máj kezelésének nehézségei.

A 52-year-old female patient was admitted to our department suffering from discomfort and tension in right side subcostal region for five months. The anamnesis contains cholecystectomy, appendectomy and gynecology treatment. CT examination and X-ray examination showed cysts in both lobe of liver. The primary treatment was ultrasonography guided punction in another department. This treatment caused anaphylactoid shock. After this dangerous treatment the patient refused the next punction. Following required arrangement laparoscopic exploration and adhaesiolysis were done in our department. Different size cysts had laparoscopically fenestrated. After half year the patient's symptoms resumed. Repeated CT and US examinations showed cysts again. Cysts were laparoscopically fenestrated again. Since the operation the patient had no complaint. Histology showed fibrocystic liver. After a month control CT examination showed cysts again. After two months we made ultrasonography guide punction of remain cysts following radiological consultation.