Maurizio Bellavia

Gut microbiota imbalance and chaperoning system malfunction are central to ulcerative colitis pathogenesis and can be counteracted with specifically designed probiotics: a working hypothesis.

In this work, we propose that for further studies of the physiopathology and treatment for inflammatory bowel diseases, an integral view of the conditions, including the triad of microbiota–heat shock proteins (HSPs)–probiotics, ought to be considered. Microbiota is the complex microbial flora that resides in the gut, affecting not only gut functions but also the health status of the whole body. Alteration in the microbiota’s composition has been implicated in a variety of pathological conditions (e.g., ulcerative colitis, UC), involving both gut and extra-intestinal tissues and organs. Some of these pathologies are also associated with an altered expression of HSPs (chaperones) and this is the reason why they may be considered chaperonopathies. Probiotics, which are live microorganisms able to restore the correct, healthy equilibrium of microbiota composition, can ameliorate symptoms in patients suffering from UC and modulate expression levels of HSPs. However, currently probiotic therapy follows ex-adiuvantibus criteria, i.e., treatments with beneficial effects but whose mechanism of action is unknown, which should be changed so the probiotics needed in each case are predetermined on the basis of the patient’s microbiota. Consequently, efforts are necessary to develop diagnostic tools for elucidating levels and distribution of HSPs and the microbiota composition (microbiota fingerprint) of each subject and, thus, guide specific probiotic therapy, tailored to meet the needs of the patient. Microbiota fingerprinting ought to include molecular biology techniques for sequencing highly conserved DNA, e.g., genes encoding 16S RNA, for species identification and, in addition, quantification of each relevant microbe.

Pancreatic islets from non-heart-beating donor pig: Two-layer preservation method in an in vitro porcine model

Purpose Pancreata from non-heart beating donors could represent an unlimited source of islets if their cell viability can be efficiently preserved during the time necessary to process the organs by the use of a better solution of preservation compared to the classic University of Wisconsin solution. The aim of this study was to determine whether it is possible to obtain functioning “alive islets” from non-heart-beating donors by comparing, on a porcine model, the classic “UW ice-store” method with a two-layer cold storage method (TLM) using oxygenated Perfluorocarbons (PFC) and UW. Methods Whole pancreata were harvested from 20 NHBDs female pigs with similar characteristics and preserved for 4 h in UW solution (n=10) or TLM (UW/PFC) solution (n=10). The isolated islets were then evaluated for number, viability, purity, and insulin secretion, also estimated after 8 weeks of cryopreservation. Results The total number of islets obtained from isolation, and their function assayed by the insulin stimulation index, before and after cryopreservation, showed a higher value in the TLM group. No significative differences in terms of purity and viability before and after cryopreservation were found when comparing the two groups. Conclusions TLM solution for NHBDs porcine pancreata with cold ischemia time lower than 4 h offers significant advantages over UW solution storage, thereby increasing the isolation yield and isolation success rate of the pancreatic porcine islets.

Granulomatous Mastitis during Chronic Antidepressant Therapy: Is It Possible a Conservative Therapeutic Approach?

Granulomatous mastitis is a rare benign inflammatory disease of the breast with multiple etiologies such as tuberculosis, sarcoidosis, foreign body reaction, and mycotic and parasitic infections. In contrast, idiopathic granulomatous mastitis (IGM) is characterized by the presence of chronic granulomatous lobulitis in the absence of an obvious etiology. Clinically and radiologically it may mimic breast carcinoma and so awareness of surgeons, pathologists, and radiologists is essential to avoid unnecessary mastectomies. Cases of IGM are reported during antidepressant therapy in patients also showing high levels of prolactinemia. In these cases, we believe that surgical excision must be avoided being replaced with a conservative management of the pathological condition based on a corticosteroid treatment.

Towards an ideal source of mesenchymal stem cell isolation for possible therapeutic application in regenerative medicine

BACKGROUND The possibility of obtaining mesenchymal stem cells (MSCs) from fetal tissue such as amniotic fluid, chorionic villi and placenta is well-known and a comparison between MSCs originating in different sources such as fetal tissue and those from bone marrow in terms of yield and function is a topical issue. The mesenchymal stem cells isolated from bone marrow are well-characterized. Unfortunately the low quantitative yield during isolation is a major problem. For this reason, other tissue sources for MSCs are of paramount importance. CONCLUSION In this review, starting from a description of the molecular and cellular biology of MSCs, we describe alternative sources of isolation other than bone marrow. Finally, we describe the potential therapeutic application of these cells.

Abnormal espansion of segmented filamentous bacteria in the gut: a role in pathogenesis of chronic in fiammatory intestinal desease

Human intestinal microbiota create a complex polymicrobial ecology characterized by high population density, wide diversity, and complexity of interactions. Any imbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequences including an increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract, which is referred to as small intestinal bacterial overgrowth (SIBO) syndrome. SIBO is frequently found in persons fulfilling criteria for irritable bowel syndrome (IBS), and the large overlapping of symptoms of these two pathological conditions led some authors to believe that IBS is secondary to SIBO. Interestingly, SIBO is also found in about 25% of patients with Crohns disease. Emerging data show that specific components of gut microbiota, particularly segmented filamentous bacteria (SFB), activate intestinal immunocompetent cells, for example, Th17 cells which have a potential role in pathogenesis of inflammatory intestinal diseases. On the basis of the aforementioned data we postulate that a previously unidentified specific form of SIBO, involving in particular the aberrant expansion of SFB in the gut, could play a role in the onset of chronic intestinal inflammatory diseases through persistent activation of Th17 cells. From this point of view, a successful therapeutic approach to inflammatory intestinal disease patients could be the administration of specific antibiotics directed against SFB to restore the physiological levels of these bacteria in the gut. Furthermore, it could be very useful to identify appropriate laboratory methodologies to monitor the level of SFB in the gut with the aim of preventing their potentially dangerous increase in numbers.

Is secondary hyperparathyroidism-related myelofibrosis a negative prognostic factor for kidney transplant outcome?

Secondary hyperparathyroidism (HP) presenting with hypocalcemia and subsequent increased parathormone (PTH), is mainly identified in patients with chronic renal failure, which has been associated with variable degrees of bone marrow fibrosis. For suitable patients with end-stage renal disease (ESRD), kidney transplantation is recognized as the therapy of choice, being superior to dialysis in terms of quality of life and long-term mortality risk; in this regard interesting data show that increased time on dialysis prior to kidney transplantation is associated with decreased graft and patient survival. In our opinion an important and until now underestimated determinant of graft survival is the proper activity of bone marrow because of the emerging role of hematopoietic stem cells (HSC) in repair of ischemia/reperfusion (IR) damage. We postulate that in ESRD patients, who usually undergo long dialytic treatment, a myelofibrosis caused by an overt secondary HP could drastically decrease the HSC potential for IR damage repair after kidney transplant; this could irremediably lead to a delay in graft function with all related complicances. If the curative role of bone marrow-derived stem cells was confirmed by more data obtained in experimental animal models, it could be possible to try a cellular-based therapeutic approach in the management of ESRD patients which are in waiting list for a kidney transplant.

Beyond Islet Transplantation in Diabetes Cell Therapy: From Embryonic Stem Cells to Transdifferentiation of Adult Cells

Exogenous insulin is, at the moment, the therapy of choice of diabetes, but does not allow tight regulation of glucose leading to long-term complications. Recently, pancreatic islet transplantation to reconstitute insulin-producing β cells, has emerged as an alternative promising therapeutic approach. Unfortunately, the number of donor islets is too low compared with the high number of patients needing a transplantation leading to a search for renewable sources of high-quality β-cells. This review, summarizes more recent promising approaches to the generation of new β-cells from embryonic stem cells for transdifferentiation of adult cells, particularly a critical examination of the seminal work by Lumelsky et al.

Sistemic calciphylaxis and thrombotic microangiopathy in a kidney transplant patient: Two mixing fatal syndromes?

Abnormalities in calcium and phosphorus metabolism are common and metabolic bone diseases develop often in patients with chronic renal failure (CRF). Effective clinical management includes measures to control phosphorus retention and prevent hyperphosphataemia, to maintain serum calcium concentrations within the normal range and to prevent excess parathyroid hormone (PTH) secretion by the judicious use of vitamin D sterols. Certain of these interventions, however, appear to increase the risk of soft tissue and vascular calcification in patients with End Stage Renal Disease (ESRD), so current therapeutic approaches are thus being re-evaluated in an effort to limit these risks. Patients with calciphylaxis have an extremely high mortality rate, diagnosis requires a high degree of clinical suspicion and the role and extent of parathyroidectomy in the management of this condition remain controversial. In some cases renal transplant patients could suffer from a comorbidity in which vascular function is compromised not only by secondary hyperparathyroidism-related calcification but also by other pathological condition as haemolytic uremic syndrome (HUS), leading to a fatal clinical outcome. We postulate that in these cases a secondary hyperparathyroidism not properly diagnosed in an early phase of the renal disease (probably before the kidney transplant) could cause a vascular calcification which, adding to the pre-existing HUS-related vascular compromission, gave rise to catastrophic clinical consequences. In the management of ESRD patients, in particular in the cases of pre-existing angiopathies, could be therefore crucial the early and proper diagnosis of an alteration of calcium-posphorus metabolism and effort of medicine could be oriented in these cases also towards identification of screening methodologies to undoubtedly assess such a diagnosis.

A complex case of fatal calciphylaxis in a female patient with hyperparathyroidism secondary to end stage renal disease of graft and coexistence of haemolytic uremic syndrome

BACKGROUND Calciphylaxis is a potentially fatal complication of persistent secondary hyperparathyroidism; its cause is still not clear. Unfortunately there is no close relation in severity of clinical picture, serological and pathological alteration. For this reason the prognosis is difficult to establish. Administration of sodium thiosulphate may reduce the precipitation of calcium crystals and improve the general clinical conditions before surgical parathyroidectomy, which seems the only therapeutic approach able to reduce the mortality risk in these patients. METHODS AND RESULTS A 60 year old female patient suffering from End Renal Stage Disease, on haemodialysis from 2001 due to the onset of haemolytic uremic syndrome, underwent a kidney transplant in April 2008. After transplantation there was a recurrence of the haemolytic uremic syndrome, with temporary worsening of the graft. Six months later there was a definite loss of graft and return to dialysis treatment. On April 2010 a severe systemic calciphylaxis related to secondary hyperparathyroidism was diagnosed. The patient underwent parathyroidectomy but, because of the unimproved clinical picture, treatment with sodium thiosulphate was initiated. There was only improvement in cutaneous lesions. The worsening general clinical condition of the patient caused death due to general septic complications. CONCLUSIONS The coexistence of haemolytic uremic syndrome and secondary hyperpathyroidism makes the prognosis poor and, in this case, therapy, which counteracts calcium crystals precipitation, has no effect. Preventive parathyroidectomy can be considered as the only possible treatment.

Dissecting the different biological effects of oncogenic Ras isoforms in cancer cell lines: Could stimulation of oxidative stress be the one more weapon of H-Ras?: Regulation of oxidative stress and Ras biological effects

Ras proteins are small GTPase functioning as molecular switches that, in response to particular extracellular signalling, as growth factors, activate a diverse array of intracellular effector cascades regulating cell proliferation, differentiation and apoptosis. Human tumours frequently express Ras proteins (Ha-, Ki-, N-Ras) activated by point mutations which contribute to malignant phenotype, including invasiveness and angiogenesis. Despite the common signalling pathways leading to similar cellular responses, studies clearly demonstrate unique roles of the Ras family members in normal and pathological conditions and the lack of functional redundancy seems to be explainable, at least in part, by the ability of Ras isoforms to localize in different microdomains to plasma membrane and intracellular organelles. This different intracellular compartmentalization could help Ras isoforms to contact different downstream effectors finally leading to different biological outcomes. Interestingly, it has also been shown that Ha- and Ki-Ras exert an opposite role in regulating intracellular redox status. In this regard we suggest that H-Ras specific induction of ROS (reactive oxygen species) production could be one of the main determinants of the invasive phenotype which characterize cancer cells harbouring H-Ras mutations. In our hypothesis then, while K-Ras (not able to promote oxidative stress) could mainly contribute to cancer progression and invasiveness through activation of MAPK and PI3K, H-Ras-mediated oxidative stress could play a unique role in modulation of intercellular contacts leading to a loss of cell adhesion and eventually also to a metastatic spread.