Alteration of Notch signaling and functionality of adipose tissue derived mesenchymal stem cells in heart failure.

AIM: Circulating mesenchymal cells increase in heart failure (HF) patients and could be used therapeutically. Our aim was to investigate whether HF affects adipose tissue derived mesenchymal cell (adMSC) isolation, functional characteristics and Notch pathway. METHODS AND RESULTS: We compared 25 patients with different degrees of HF (11 NYHA classes I and II and 14 NYHA III and IV) with 10 age and gender matched controls. 100% adMSC cultures were obtained from controls, while only 72.7% and 35.7% from patients with mild or severe HF (p<0.0001). adMSC from HF patients showed higher markers of senescence (p16 positive cells: 14±2.3% in controls and 35.6±5.6% (p<0.05) and 69±14.7% (p<0.01) in mild or severe HF; γ-H2AX positive cells: 3.7±1.2%, 19.4±4.1% (p<0.05) and 23.7±3.4% (p<0.05) respectively), lower proliferation index (Ki67 positive cells: 21.5±4.9%, 13.2±2.8% and 13.7±3.2%, respectively), reduced pluripotency-associated genes (Oct4 positive cells: 86.7±4.9%, 55±12% (p<0.05) and 43.3±8.7% (p<0.05), respectively; NANOG positive cells: 89.8±3.7%, 39.6±14.4% (p<0.01) and 47±8.1%, respectively), and decreased differentiation markers (α-sarcomeric actin positive cells: 79.8±4.6%, 49±18.1% and 47±12.1% (p<0.05) and CD31-positive endothelial cells: 24.5±2.9%, 0.5±0.5% (p<0.001) and 2.3±2.3% (p<0.001), respectively). AdMSC from HF patients also showed reduced Notch transcriptional activity (lowered expression of Hey 1 and Hey 2 mRNAs). Stimulation with TNF-α of adMSC isolated from controls affected the transcription of several components of the Notch pathway (reduction of Notch 4 and Hes 1 mRNAs and increase of Notch 2 and Hey 1 mRNAs). CONCLUSIONS: In HF yield and functionality of adMSC are impaired and their Notch signaling is downregulated.

Stem cell senescence and regenerative paradigms.

The term "cellular senescence" denotes a cellular response to several stressors that results in irreversible growth arrest, alterations of the gene expression profile, epigenetic modifications, and an altered secretome, all of which eventually impair the reparative properties of primitive cells, adding a layer of complexity to the field of regenerative medicine. The purpose of this review is to illustrate how cellular senescence could affect tissue repair and to propose interventions that aim at interfering with it.

Concerns and hopes for stem cell therapy in cardiology: focus on endothelial progenitor cells.

The crucial role played by the endothelium in cardiovascular disorders has been repetitively recognised. Endothelium injury has been implicated in atherosclerosis, thrombosis, hypertension and other cardiovascular diseases. Recently, however, research has undertaken a new avenue. As mature endothelial cells posses limited regenerative capacities, the interest has been switched to the circulating endothelial progenitor cells (EPCs). Indeed, the scientific community has made progress in understanding the role of EPCs in the maintenance of endothelial integrity and function as well as post natal neovascularisation. It has been suggested that these cells are able to home in the site of heart injury / damage and that they might take part in angiogenesis, giving hope for new treatment opportunities. There is evidence that reduced availability of EPCs or impairment of their function is associated with more severe CV disease and to comorbid risk factors. Different current drug regimes are able to influence bone marrow production and release of EPCs and several growth factors are considered for possible useful new therapeutic approaches. Thus, many studies into the potential use of EPCs in the clinical setting have recently been conducted with conflicting results. The goal of this review article is to discuss current therapies to regenerate new vessels and therefore to enhance myocardial function. The article overviews the search strategy and the pathophysiological aspects behind this therapy, consider the target currently under investigation and set the stage for new ideas.

UVC radiation-induced effect on human primary thyroid cell proliferation and HLA-DR expression.

The aim of this study was to examine how UVC irradiation will affect normal human thyroid cell proliferation and HLA-DR expression. Primary human thyroid cells were exposed to UVC (254 nm wavelength) irradiation. In some experiments 0.5 mM buthionine sulfoximine (BSO) was added. Apoptosis was detected measuring annexin V, proteins involved in apoptotic process (p53, Bax, Bcl-2, caspase 3, and 9) by immunoblot analysis and HLA-DR expression by FACS. UVC induced a cell cycle arrest in G0/G1 phase in the first 24 h, accumulation of cells in the S phase 72 h after treatment, and an increase of apoptotic cells. BSO pretreatment showed an earlier appearance and a higher percentage of apoptosis. p53, caspase 3 and 9 were increased, while Bax and Bcl-2 were decreased. We also observed a transient significant increase in HLA-DR expression. UVC inhibited cell proliferation and induced apoptosis in normal human primary thyroid cells. An inhibitor of glutathione synthesis induced an earlier appearance and higher percentage of apoptosis suggesting that oxidative stress may play a role. Apoptotis involved components of the intrinsic mitochondrial pathway. A transient increase in HLA-DR expression after UVC irradiation could play a role in inducing AITD.

Apurinic apyrimidinic endonuclease/redox effector factor 1 immunoreactivity and grading in hepatocellular carcinoma risk of relapse after liver transplantation.

Apurinic apyrimidinic endonuclease (APE1)/redox effector factor 1 (Ref-1), which is a multifunction protein involved in both transcriptional regulation of gene expression during adaptive cellular responses to oxidative stress and in the base excision repair pathway of DNA lesions generated as a consequence of oxidant-induced base damage, contributes to the maintenance of genome stability. APE1/Ref-1 is normally localized in the nucleus; cytoplasmic localization observed in several tumors has been correlated with a poor prognosis. Hepatocellular carcinoma (HCC) grading is an essential tool to predict the risk of relapse and patient prognosis, particularly in patients undergoing liver transplantation (OLT). The aim of this study was to identify the role of APE1/Ref-1 in predicting a posttransplant HCC relapse. We studied 48 patients transplanted for HCC to define grading as well as nuclear and cytoplasmic APE1/Ref-1 expression within neoplastic versus nonneoplastic parenchyma. We defined a cutoff of 60% of cytoplasmic APE1/Ref-1 expression to identify positive cases. At a minimum of 1.5-year follow-up after transplantation, 32 patients are alive and 16 patients are deceased after HCC relapse. Among low-grade HCC (grades 1 and 2), 76% of cases are alive; only 34% showed cytoplasmic APE1/Ref-1 immunoreactivity. Among the high-grade cases (grades 3 and 4), 50% were alive with 64% showing cytoplasmic immunoreactivity. Nuclear reactivity was generally similar either in neoplastic or in cirrhotic livers, irrespective of the grade. These data seemed to support the hypothesis of a predictive role of APE1/Ref-1 for HCC risk of relapse, which together with tumor grade by analysis of a pretransplant needle biopsy should aid decision making for OLT.

eSlide suite: an open source software system for whole slide imaging.

This short report briefly describes the principles underlying the telepathology technique known as whole slide imaging, and the design and implementation of a system for acquisition and visualisation of digital slides. The developed system, including an acquisition module and a visualisation module, is available as an open source on the Internet, together with sample acquired slides.

Evaluation of prostate cancer staging in organ donors: intraoperative histology on periglandular soft tissues-a proposal.

An histopathologic screening method for prostate cancer assessment in organ donors is crucial because of the widening of the donor pool to older individuals. Evaluation of cancer grading with multiple biopsies is fundamental in the cases of abnormal prostate-specific antigen (PSA) values and suspect ultrasound findings. However, multiple biopsies may fail to represent the whole neoplasia, and grading may be difficult particularly because there may not be information about capsular penetration. Since October 2007, 20 prostate autopsy specimens were submitted to an histopathologic screening method of the entire prostate based on extemporary frozen section analysis (maximum 75 minutes) of shavings of samples of the lateral surfaces of the prostate gland: namely, approximately 5 samples or 7 in the case of a large gland. We produced 3-mm-thick step sections at three levels: the first was immediately taken at the cutting level, and then 30-microm sections were discarded. The following three levels of 5 microm intervals for 10 sections for each level were evaluated. There were 7 cases of undiagnosed prostate cancer, three of which were demonstrated on frozen sections with neoplastic foci of extraglandular infiltration within connective and adipose tissues outside the gland. No neoplasia was present in the other 13 cases. In all cases, the final diagnosis was confirmed by the extemporary analysis. Our goal was to confirm the optimal number of samples that were representative of the whole prostatic contour, to define time to diagnosis and to evaluate reproducibility of frozen-section histopathologic screening compared with paraffin sections. This novel approach should permit a more refined risk-benefit analysis.

Co-localization of tryptase and cathepsin-G in mast cells in cutaneous mastocytosis.

Mastocytosis is a heterogeneous disease characterized by an abnormal growth and/or accumulation of clonal mast cells (MC) in one or more organs. The most frequent site of organ involvement is the skin. The aim of this study was to investigate the immunoreactivity to tryptase and to cathepsin-G of MC from human cutaneous mastocytosis and to compare their number in normal skin and cutaneous mastocytosis. Immunohistochemistry and dual immunofluorescence using anti-tryptase and anti-capthepsin-G antibodies was performed on biopsy specimens from 20 cases diagnosed as cutaneous mastocytosis. Tryptase-positive MC was more numerous as compared to cathepsin-G positive MC. Dual immunofluorescence for tryptase and cathepsin-G demonstrated a colocalization of tryptase and cathepsin-G in skin MC secretory granules. Morphometric evaluation of MC number demostrated that the number of both tryptase- and cathepsin-G-positive MC was significantly higher in cutaneous mastocytosis as compared to normal skin and that in both conditions the number of tryptase-positive MC was significantly higher as compared to the number of cathepsin-G-positive MC. In conclusion, in this study, for the first time we have demonstrated the presence of MC with immunoreactivity to cathepsin-G in human cutaneous mastocytosis, as well as the co-localization of tryptase and cathepsin-G in MC secretory granules.

Angiogenesis and mast cells in human breast cancer sentinel lymph nodes with and without micrometastases.

AIMS: An increasing number of mast cells have been reported in angiogenesis associated with solid and haematopoietic tumours. Data concerning the number of mast cells in neoplastic lymph nodes and their relationship with microvessel density are controversial. The aim was to correlate the extent of angiogenesis with the number of mast cells reactive with tryptase in biopsy specimens of sentinel lymph nodes with and without micrometastases obtained from patients with breast cancer. METHODS AND RESULTS: Specimens from sentinel lymph nodes obtained from 80 patients (40 with and 40 without micrometastases) were investigated immunohistochemically by using anti-CD31 and anti-tryptase antibodies. Angiogenesis, measured as microvessel counts, increased in parallel with the number of tryptase-positive mast cells and their values were significantly higher in lymph nodes with micrometastases compared with those without. CONCLUSIONS: Tryptase-positive mast cells may contribute, at least in part, to angiogenesis occurring in sentinel lymph nodes with micrometastases from patients with breast cancer.

Bone marrow B-cell clonal expansion in type II mixed cryoglobulinaemia: association with nephritis.

OBJECTIVES: To investigate the relationship between the pattern of bone marrow (BM) B-cell expansion and the clinical features of mixed cryoglobulinaemia (MC) syndrome. METHODS: Fifty-five patients with type II MC syndrome were analysed. Their median age was 64 yrs (range 24-82), the median disease duration was 6 yrs (range 1-26) and the mean follow-up after BM analysis was 2.65 yrs (s.d. = 1.33). Peripheral neuropathy was present in 33 patients (60%), nephritis in 14 (25.4%), skin ulcers in 14 (25.4%) and lymphoma or atypical lymphoproliferative disorder (LPD) in 17/55 (30.9%). Anti-HCV antibodies were found in 43/55 patients (78.2%). BM B-cell expansion was evaluated by a semi-nested PCR amplification of the V-D-J region of the IgH genes. RESULTS: A clonal B-cell expansion in the BM was found in 33/55 (60%) patients, while a polyclonal pattern in 22/55 (40%). A BM pattern of clonal B-cell expansion increased the risk of nephritis of about 10 times [odds ratio (OR) = 10.11, CI95%1.52-67.31], if compared to a polyclonal pattern. In contrast, the risk of skin ulcers was decreased in BM clonal cases (OR = 0.09, CI95%0.02-0.49). Overt lymphomas did not emerge from patients with BM monoclonal expansion (without clinical or histopathological features of lymphoproliferation; or with LPD) in a short-term, consistent with the finding that monoclonality was associated with nephritis and not with an underlying, not recognized lymphoma. CONCLUSION: BM clonal B-cell expansion is associated with nephritis in MC syndrome. Particular B-cell clones may be preferentially expanded and may play a pathogenic role in MC nephritis.

Superiority of transplantation versus resection for the treatment of small hepatocellular carcinoma.

The best therapy for hepatocellular carcinoma (HCC) is still debated. Hepatic resection (HR) is the treatment of choice for single HCC in Child A patients, whereas liver transplantation (OLT) is usually reserved for Child B and C patients with multiple nodules. The aim of this study was to compare HR and OLT for HCC within the Milan criteria on an intention-to-treat basis. Forty-eight patients were treated by OLT and 38 by HR. Three- and 5-year patient survival rates were significantly higher (P = .0057) in the OLT group (79% and 74%) than after HR (61% and 26%). The 3- and 5-year disease-free survival rate was better (P = .0005) for OLT (74% and 74%) versus HR (41% and 11%). The probability of HCC recurrences after resection was greater (P = .0002) than after transplantation, achieving 31% and 76% for HR and 2% and 2% for OLT at 3 and 5 years after surgery. The median waiting list time was 118 days; two patients dropped out for HCC progression. We concluded that OLT is superior to HR for small HCC in cirrhotic patients assuming that OLT can be performed within 6 to 10 months after listing to reduce dropouts due to tumor progression.

Treatment of inclusion body myositis with cyclosporin-A or tacrolimus: successful long-term management in patients with earlier active disease and concomitant autoimmune features.

OBJECTIVE: Sporadic inclusion body myositis (s-IBM) is a chronic, progressive, inflammatory myopathy of unknown aetiology, generally resistant to immunosuppressive therapy. Given that lymphocyte infiltrates in s-IBM muscle tissue are CD8+ T cells, targeting these cells may represent a valid approach. PATIENTS AND METHODS: Three patients with biopsy-proven s-IBM, high creatine kinase levels at diagnosis, two of whom with associated immune disorders, were treated with either cyclosporin-A (CyA) or tacrolimus, in combination with high doses of corticosteroids (CS), followed by rapid CS tapering. Clinical assessment and laboratory evaluation were performed every three months for the first year and then every six months for the second year. RESULTS: Based on muscle strength assessment and muscle enzyme serum levels, a major clinical response was observed at month +3 in two out of the three patients. A complete clinical response and major clinical response were obtained at month +6, in two and one patient, respectively. Normalization of serum muscle enzymes was observed in all. Steroids could be tapered to very low doses in all patients and were suspended early in one. Laboratory, but not clinical relapse occurred in one patient and was controlled by increasing the CyA dose. Treatment was well tolerated, with no serious adverse events occurring. All three patients are maintaining immunosuppressive therapy. CONCLUSION: Calcineurin inhibitors may represent a useful option for the long-term management of s-IBM, possibly in a subset characterized by a short duration with high disease activity or associated autoimmune manifestations.

Comparison of clinical and pathological staging and long-term results of liver transplantation for hepatocellular carcinoma in a single transplant center.

Liver transplantation (OLT) is a treatment for hepatocellular carcinoma (HCC) superimposed on cirrhosis provided that the disease meets defined criteria. The aim of the study was to evaluate our experience with respect to clinical and pathological staging and long-term results. From 1996 to 2005, 50 patients underwent OLT for HCC including 43 men (86%) and seven women (14%) of median age 57 years (range 37 to 67). All patients fulfilled the Milan criteria. The HCC diagnosis was based on preoperative imaging and alpha-fetoprotein levels; no tumor biopsy was performed. Upon histological examination of the resected specimens, we discovered 6 (12%) incidentalomas and 8 (16%) cases of no HCC. Finally we had 42 "true" HCC. Twenty-six patients (52%) have been downstaged and 10 (20%) upstaged by preoperative imaging; 15% were pT1, 45% were pT2, 27% pT3, and 13% pT4a. Twenty-six percent of cases exceeded the Milan criteria. One patient (pT4a) with microvascular invasion died of pulmonary metastases at 14 months after transplantation. No HCC recurrences within the liver have been encountered at a median follow-up of 20 months (range 0 to 80 months). Overall the estimated 1-, 3-, and 5-year survival rates were 83%, 77%, and 72%, respectively. One-, 3-, and 5-year estimated survival rates were 87%, 75%, and 75% for pT1, and pT2, and 75%, 67%, and 67% for pT3 and pT4a, respectively (P = .99). Based on our experience OLT for HCC has long-term results comparable to those without HCC despite the presence of a significant number of cases exceeding the Milan criteria upon pathological staging.

Do mast cells affect villous architecture? Facts and conjectures.

In adult life, the architecture of the intestinal villus is maintained by a complex series of epithelial-stromal interactions that involve different types of fixed and mobile cells located in the intestinal mucosa. Mast cells (MC) are normal constituents of the small bowel mucosa where they reside in the villous and pericryptal lamina propria as well as within the columnar epithelial cell layer. Besides being involved in numerous immune and inflammatory reactions in the context of both innate and acquired host defence, MC are known to exert important non-immunological functions like wound repair, extracellular matrix remodelling, angiogenesis and neurotrophism as well as modulation of fibroblast, epithelial cell and smooth muscle cell activity. These pleiotropic functions put MC in a central, strategic position to organize tissue defence, restore tissue damage and maintain tissue homeostasis. This review summarizes the most recent advances concerning the functional anatomy of the crypt-villus unit and discusses the way intestinal MC might become part of the instructive circuits that ultimately lead to the maintenance of a proper villous shape.

The thymus is a site of mast cell development in chicken embryos.

Thymic mast cells were studied by light and transmission electron microscopy in chicken embryos during organogenesis. Mast cells made their first appearance at day 15. At days 16 and 17, there was a burst of mast cell development with a peak of 278 +/- 54 cells/mm(2) at day 16. Then, mast cell density decreased until hatching. During the whole embryonic period, about 80% of mast cells localized to the thymic medulla. In the cortex, they were less numerous, and some rare mast cells could be identified in the capsule and septa. Thymic mast cells could be recognized in association with hematopoietic foci, but frequently they grew independently from areas of hematopoiesis and appeared as single cells interspersed among thymocytes, thymic epithelial cells, and interdigitating cells. They were often recognized in close relationship with the scanty and delicate extracellular matrix of the developing gland. Viewed by electron microscopy, mast cells were relatively small cells, with a few secretory granules. Exocytosis was never seen, but, notably, granules emptied in a piecemeal degranulation fashion. This study demonstrates that the chicken thymus is a site of mast cell development during embryogenesis. The high mast cell density we found suggests a possible role for these cells during thymus organogenesis.

The mast cell: an active participant or an innocent bystander?

Mast cells (MC) are phylogenetically old cells which are distributed throughout the human organism and, on the whole, occupy roughly the volume of the spleen. MC have long been recognized as key cells of type I hypersensitivity reactions. Several lines of evidence, however, indicate that they not only express critical effector functions in classic IgE-associated allergic disorders, but also play important roles in host defence against parasites, bacteria and perhaps even viruses. Indeed, it is now clear that MC can contribute to host defence in the context of either acquired or innate immune responses through the release of a myriad of pro-inflammatory and immunoregulatory molecules and the expression of a wide spectrum of surface receptors for cytokines and chemokines. Moreover, there is growing evidence that MC exert distinct non-immunological functions, playing a relevant role in tissue homeostasis, remodeling and fibrosis as well as in the processes of tissue angiogenesis. In this review, we provide a small insight into the biology of human MC and their potential implications in clinical pathology.

Low mast cell density in the human duodenal mucosa from chronic inflammatory duodenal bowel disorders is associated with defective villous architecture.

BACKGROUND: Mast cells (MC) have recently been implicated in the processes of tissue homeostasis, remodeling and repair. DESIGN: In this study, the total and tryptase-reactive mast cell populations were quantified in the duodenal mucosa of 27 subjects suffering from chronic inflammatory bowel disorders. Mast cell density was both related to the general villous architecture (normal or defective) and to the microvascular density in the duodenal mucosa. RESULTS: Total mast cell and tryptase-positive mast cell subpopulation densities were found to be significantly reduced in the samples with defective villous architecture in comparison with those exhibiting a normal villous profile. In these last samples, a relevant proportion of mucosal mast cells exhibited ultrastructural features of secretory activity, in particular piecemeal degranulation. Finally, no correlation was established between microvascular density and tryptase activity, as it has been previously demonstrated in other pathological conditions. CONCLUSIONS: Overall, these findings indicate a significant correlation between mast cell density and the duodenal mucosal architecture.

Evidence that human cardiac myocytes divide after myocardial infarction.

BACKGROUND: The scarring of the heart that results from myocardial infarction has been interpreted as evidence that the heart is composed of myocytes that are unable to divide. However, recent observations have provided evidence of proliferation of myocytes in the adult heart. Therefore, we studied the extent of mitosis among myocytes after myocardial infarction in humans. METHODS: Samples from the border of the infarct and from areas of the myocardium distant from the infarct were obtained from 13 patients who had died 4 to 12 days after infarction. Ten normal hearts were used as controls. Myocytes that had entered the cell cycle in preparation for cell division were measured by labeling of the nuclear antigen Ki-67, which is associated with cell division. The fraction of myocyte nuclei that were undergoing mitosis was determined, and the mitotic index (the ratio of the number of nuclei undergoing mitosis to the number not undergoing mitosis) was calculated. The presence of mitotic spindles, contractile rings, karyokinesis, and cytokinesis was also recorded. RESULTS: In the infarcted hearts, Ki-67 expression was detected in 4 percent of myocyte nuclei in the regions adjacent to the infarcts and in 1 percent of those in regions distant from the infarcts. The reentry of myocytes into the cell cycle resulted in mitotic indexes of 0.08 percent and 0.03 percent, respectively, in the zones adjacent to and distant from the infarcts. Events characteristic of cell division--the formation of the mitotic spindles, the formation of contractile rings, karyokinesis, and cytokinesis--were identified; these features demonstrated that there was myocyte proliferation after myocardial infarction. CONCLUSIONS: Our results challenge the dogma that the adult heart is a postmitotic organ and indicate that the regeneration of myocytes may be a critical component of the increase in muscle mass of the myocardium.

Combined analysis of MIB-1 and thyroid transcription factor-1 predicts survival in non-small cell lung carcinomas.

The prognostic value of combined immunohistochemical analysis for the thyroid transcription factor-1 (TTF-1) and the proliferation marker MIB-1 was assessed in a consecutive series of non-small cell lung carcinomas (NSCLC). Tumor immunoreactivity for TTF-1 and MIB-1 was classified in three groups (-,+,++) and in two groups (-,+), respectively. Comparison across groups for TTF-1 reactivity showed significantly different survival curves (P=0.04). In particular, the best prognosis was associated with a TTF-1 negative pattern, whereas the TTF-1 '++' cases showed the worst prognosis. A trend towards better prognosis was observed for MIB-1 negative cases (P=0.09). Multivariate analysis confirmed independent prognostic significance of TTF-1 (P=0.002), MIB-1 (P=0.01) and pStage (P=0.04). Accordingly, analysing TTF-1 and MIB-1 together, a better prediction of survival was obtained (P=0.02), with the poorest prognosis for the 'TTF-1++/MIB-1+' cases.