Strongyloides stercoralis infection in San Marino Republic: first epidemiological data from an observational study.

Strongyloides stercoralis is a neglected parasite that can cause death in immunocompromised individuals. There were no data on the epidemiology of S. stercoralis infection in San Marino Republic until two patients (one of whom died) were diagnosed with severe strongyloidiasis (hyperinfection) between September 2016 and March 2017. A serology test for Strongyloides spp. was introduced in routine practice in the laboratory of the State Hospital to test patients considered to be at risk for strongyloidiasis. Between August 2017 and August 2018, of 42 patients tested with serology, two (4.8%) were positive. An additional case was found by gastric biopsy. Two of the positive cases were presumably autochthonous infections (elderly people with no significant travel history), while the other was a probable imported case (young man born in Nigeria and settled in Europe since 2003). Epidemiology of strongyloidiasis in San Marino might be similar to Northern Italy, where a relevant proportion of cases was diagnosed in immigrants (mainly from sub-Saharan Africa) and in elderly Italians with eosinophilia. Screening for strongyloidiasis might be worthwhile in inhabitants of San Marino in the same categories of individuals, particularly those at risk of immune suppression.

cDNA-microarray analysis as a new tool to predict lymph node metastasis in gastric cancer.

BACKGROUND: The aim of the present study was to investigate whether microarray gene expression analysis can be used to predict lymph node status in gastric cancer. METHODS: Twenty-nine patients undergoing gastrectomy for cancer were enrolled and subdivided according to the pathologic nodal involvement of their disease (N+ vs. N0). Molecular profiling was performed by cDNA microarray on tumor tissue and healthy mucosa. Data were processed to identify differently expressed genes. Selected genes were categorized with gene ontology. RESULTS: Compared to healthy gastric mucosa, 52 genes were differently expressed in N+ patients, and 50 genes in N0 patients. Forty-five genes were similarly regulated in N+ and N0 patients, whereas 12 genes were differently expressed between N+ and N0 patients. Seven genes were exclusively expressed in N+ patients: Egr-1 was upregulated; Claudin-18, AKR1C2, Cathepsin E, CA II, TFF 1, and progastricsin were downregulated. Five genes were exclusively expressed in N0 patients: Complement C5 receptor 1, PLA2/VII, and MMP- 9 were upregulated; MAO-A and ID-4 were downregulated. CONCLUSIONS: Microarray analysis could be a valuable tool to identify genes associated with lymph node metastasis in gastric cancer. This technique could improve the selection of patients with locally advanced disease who are candidates for extended lymph node dissection, multimodal treatment options, or alternative therapeutic strategies.

Adipose tissue-derived mesenchymal stem cells and hepatic differentiation: old concepts and future perspectives.

Mesenchymal stem cells (MSCs) are multipotent cells, able to differentiate into elements of the mesodermal lineage. Bone marrow and adipose tissue represent the main sources for MSC isolation. In the last decade, several studies have reported the plasticity of MSCs toward a hepatocyte-like phenotype. The use of MSCs to generate hepatocyte-like cells holds great promises to overcome the scarcity of available organs for transplantation. However, little is known about the molecular pathways involved in lineage cross-differentiation and several issues remain to be answered before MSC application in clinical settings. Aim of this review is to critically analyze the possible sources of MSCs suitable for liver repopulation and the molecular mechanisms underlying MSC hepatic differentiation.

Small bowel nonendocrine neoplasms: current concepts and novel perspectives.

Although small bowel nonendocrine neoplasms are rare, their incidence has increased dramatically over the past 30 years. Small bowel malignacies can be classified depending upon their cellular origin into four principal histotypes: carcinoid tumors, adenocarcinomas, lymphomas and mesenchymal tumors. Until a few years ago, the treatment of small bowel tumors had remained relatively unchanged, with little progress in the development of effective adjuvant therapies and in the improvement of long-term survival over time. Recently, the growing interest in the understanding of the mechanisms underlying carcinogenesis has offered novel insights for the diagnosis and therapy of small bowel tumors. This review summarizes the state-of-the-art of small bowel nonendocrine tumors and the recent advancements in the knowledge of their molecular pathogenesis and cellular origin, with particular emphasis on stem cell research field.

Mesenchymal stromal cells multipotency and plasticity: induction toward the hepatic lineage.

BACKGROUND: Human mesenchymal stromal cells (MSCs) can be isolated from a variety of adult and perinatal tissues and exert multipotency and self renewal properties which make them suitable for cell-based therapy. Their potential plasticity extended to non-mesodermal-derived tissues has been indicated, although it is still a debated issue. In this study we have isolated MSCs from both adult and fetal tissues. Their growth, immunophenotype and multi-lineage differentiation potentials have been analyzed, focusing, in particular, on the hepatic differentiation. METHODS: Cells were isolated from bone marrow (BMSC), adipose tissue (ATSC) and second trimester amniotic fluid (AFSC), upon a written informed consent obtained from donor patients. Cells were expanded and growth kinetics was assessed by means of proliferation assay. Their immunophenotype was analyzed using cytometry and multi-lineage differentiation potential was evaluated by means of in vitro differentiation assays. Finally, the expression of tissue-specific markers was also assessed by mean of semi-quantitative PCR. RESULTS: Bipolar spindle-shaped cells were successfully isolated from all these tissues. Interestingly, ATSCs and AFSCs showed a higher proliferation potential than BMSCs. Mesodermal differentiation capacity was verified in all MSC populations, even if AFSCs were not able to undergo adipogenesis in our culture conditions. Furthermore, we showed that MSC cultured in appropriate conditions were able to induce hepatic-associated genes, such as ALB and TDO2. CONCLUSION: Taken together the data here reported suggest that MSCs from both adult and fetal tissues are capable of tissue-specific commitment along mesodermal and non-mesodermal lineages. In particular we have demonstrated that a specific hepatogenic commitment can be efficiently induced, proposing these cells as suitable tool for cell-based applications aimed at liver regeneration.

Isolation and characterization of CD133+ cell population within human primary and metastatic colon cancer.

BACKGROUND: "Cancer stem cells" (CSC) have been identified as a minority of cancer cells responsible for tumor initiation, maintenance and spreading. Although a universal marker for CSC has not yet been identified, CD133 has been proposed as the hallmark of CSC in colon cancer. The aim of our study was to assess the presence of a CD133+ cell fraction in samples of colon cancer and liver metastasis from colon cancer and evaluate their potential as tumor-initiating cells. METHODS: Tissue samples from 17 colon cancers and 8 liver metastasis were fragmented and digested using collagenase. Cell suspensions were characterized by flow cytometry using anti-CD133, CD45 and CD31 antibodies. CD133+ cells were also isolated by magnetic cell sorting and their tumor-initiating potential was assessed versus the remaining CD133- fraction by soft-agar assay. RESULTS: Our results confirmed the existence of a subset of CD133+ tumor cells within human colon cancers. Interestingly, CD133+ cells were detectable in liver metastasis at a higher percentage when compared to primary tumors. Soft-agar assay showed that CD133+ cell fraction was able to induce larger and more numerous colonies than CD133-cells. CONCLUSION: Our findings data that the CD133+ colon cancer cells might play an important role in both primary tumors as well as in metastatic lesions thus warranting further studies on the role(s) of this subset of cells in the metastatic process.

Efficacy of Lactobacillus GG in maintaining remission of ulcerative colitis.

BACKGROUND: Aminosalicylates are the mainstay of therapy to prevent relapse of quiescent ulcerative colitis. The rationale for using probiotics is based on the evidence implicating intestinal bacteria in the pathogenesis of this disorder. AIM: To evaluate the efficacy of Lactobacillus GG alone or in combination with mesalazine vs. mesalazine as maintenance treatment in ulcerative colitis. PATIENTS AND METHODS: 187 ulcerative colitis patients with quiescent disease were randomized to receive Lactobacillus GG 18 x 10(9) viable bacteria/day (65 patients), mesalazine 2400 mg/day (60 patients) or Lactobacillus GG + mesalazine (62 patients). Disease activity index, endoscopic and histological scores were determined at 0, 6 and 12 months and in case of relapse. The primary end point was to evaluate sustained remission. RESULTS: Overall analysis showed no difference in relapse rate at 6 (P = 0.44) and 12 months (P = 0.77) among the three treatment groups. However, the treatment with Lactobacillus GG seems to be more effective than standard treatment with mesalazine in prolonging the relapse-free time (P < 0.05). CONCLUSIONS: Lactobacillus GG seems to be effective and safe for maintaining remission in patients with ulcerative colitis, and it could represent a good therapeutic option for preventing relapse in this group of patients.

Onset of ulcerative colitis after thyrotoxicosis: a case report and review of the literature.

OBJECTIVE: Ulcerative colitis is a chronic disease that could be triggered by acute stressful events, such as gastrointestinal infections or emotional stress. PATIENTS AND METHODS: We reported the case of the onset of an ulcerative colitis after a thyrotoxicosis crisis and reviewed the literature about the relationships between thyroid dysfunctions and ulcerative colitis. RESULTS: A 38-year-old woman was diagnosed with ulcerative colitis after her third thyrotoxicosis crisis, two years after the diagnosis of Graves' disease. In this case, thyrotoxicosis acted as a trigger for ulcerative colitis onset. CONCLUSIONS: Hyperthyroidism could be a trigger able to elicit ulcerative colitis in susceptible patients.

How does human stem cell therapy influence gene expression after liver injury? Microarray evaluation on a rat model.

BACKGROUND: Tissue homeostasis is guaranteed by stem proliferating reserve, depending on dynamic changes in gene expression. A high plasticity is shown by the haematopoietic stem cells, potential source for liver regeneration. AIM: We aimed to evaluate the gene expression modifications induced by human haematopoietic stem cell therapy after liver injury in rats. SUBJECTS: Rats were sorted as follows: (A) human-haematopoietic stem cell injection after allyl alcohol liver damage; (B) only haematopoietic stem cell injection; (C) only allyl alcohol injection; and (D) sacrifice without any treatment. METHODS: Livers, spleens and bone marrows were analysed with flow-cytometry. Livers were also studied by reverse-transcription PCR, histology, immunohistochemistry and microarray analysis; selected genes were confirmed by real-time PCR. RESULTS: In subset A, haematopoietic stem cells were selectively recruited by liver, with respect to the group B, and they improved the liver regeneration process compared to group C. As regards microarrays, haematopoietic stem cell infusion upregulates 265 genes and downregulates 149 genes. Differentially regulated genes belong to a broad range of functional pathways, including proliferation, differentiation, adhesion/migration and transcripts related to oval-cell activation. Real-time PCR validated array results. CONCLUSIONS: Our study confirmed the capacity of haematopoietic stem cells to contribute to liver regeneration. Moreover, microarray analysis led to the identification of genes whose regulation strongly correlates with a more efficient process of liver repair after haematopoietic stem cell injection.

Improvement of mortality rate and decrease in histologic hepatic injury after human cord blood stem cell infusion in a murine model of hepatotoxicity.

BACKGROUND AND AIMS: Because of their plasticity potential local and systemic application of cord blood stem cells may represent excellent candidates for cell-based therapeutic strategies in toxic liver injuries. It is already known that intraperitoneal administration of hematopoietic stem cells provides rapid liver homing in animal models of hepatic injury. We sought to assess the efficacy of a hematopoietic stem cell infusion to decrease the histologic damage and the mortality rate of animals previously damaged by allyl alcohol. MATERIAL AND METHODS: NOD/SCID mice were divided into two groups. (1) animals treated by intraperitoneal administration of allyl alcohol and (2) animals treated with allyl alcohol and 24 hours later with an intraperitoneal infusion of human cord blood cells. Flow cytometry, histology, immunohistochemistry, and RT-PCR were performed to monitor human cell engraftment by evidences of human hepatic markers. RESULTS: Human stem cells were able to transdifferentiate into hepatocytes, improve liver regeneration after damage, and reduce the mortality rate even when requiring qualitative and quantitative differences in the transdifferentiation processes. The mortality rate decreased from 70% to 20%, with a significant improvement in the histologic findings. CONCLUSION: We demonstrated that the infusion of hematopoietic stem cells into the liver in the early stage of damage might initiate endogenous hepatic tissue regeneration that oppose the injury inflicted by toxicants.

No evidence of hematopoietic stem cell mobilization in patients submitted to hepatectomy or in patients with acute on chronic liver failure.

BACKGROUND: Liver regeneration is a heterogeneous phenomenon involving the proliferation of different cell lineages in response to injury. Under a strong positive selection pressure bone marrow derived stem cells may be involved in this process, by making a contribution to both parenchymal restoration and endothelial cell replacement. We investigate bone marrow stem cell migration to the liver in patients undergoing hepatectomy or with acute on chronic liver failure. METHODS: We enrolled 6 patients submitted to hepatectomy, 6 patients to cholecystectomy and 8 patients with acute decompensation of liver cirrhosis. Mobilization of CD34+ cells was evaluated by cytofluorimetry on peripheral blood samples at different time points; baseline, 1, 3, 7, 15 and 30 days after surgery and at admission, 1, 7 and discharge among patients with acute on chronic liver failure. 10 healthy subjects undergoing blood donation were also enrolled to evaluated the basal value of CD34+ cells. RESULTS: White blood cell counts remained in the normal range (4.1-9.8 x 10(9)/L) in all groups throughout the follow-up. In all patients of Groups 1, 2 and 3, circulating CD34+ failed to show statistically significant differences both as the absolute number and as the percentage at any time point compared to healthy controls. CONCLUSIONS: Bone marrow derived cell mobilization can not be detected after hepatectomy or during an acute decompensation on a cirrhotic liver. Under these circumstances liver regeneration can probably call upon mature hepatocytes and endogenous progenitor cells. The involvement of extrahepatic progenitors if any, is a rare and limited phenomenon.

Transdifferentiation of stem cells in pancreatic cells: state of the art.

Among the different approaches for diabetes mellitus-pancreas and pancreatic islet transplantation-the use of stem cells represent a renewable alternative source of insulin-producing cells. Stem cells capable of differentiating into beta-like cells can be isolated namely from embryonic cells, bone marrow, and umbilical cord blood, but also from adult organs such as pancreas, liver, and spleen. Several studies have demonstrated that by manipulating culture conditions and using growth and transcription factors of beta-cell lineage (in particular pdx-1 and pax4), embryonic stem cells can differentiate in vitro after formation of embryoid bodies. Bone marrow stem cells can give rise to mesenchymal; endodermal-, and ectodermal-derived cells. In vivo it has been shown that after bone marrow transplantation, using a murine sex-mismatched model, insulin-producing cells expressing the Y chromosome can be detected in the donor pancreas, although not in a significantly number. Cells characterized by a group of markers (Nestin, CK-8, CK-18) and transcription factors (Isl-1, Pdx-1, Pax-4, Ngn-3) important for beta-cell differentiation have been detected in umbilical cord blood. The recent evidence of the possibility to transdifferentiate stem cells to beta cells encourages further studies in animal models to exhaustively determine the differentiation pathways of stem cells to insulin producing cells. These findings might open the way to a successful human investigation.

Human cordonal stem cell intraperitoneal injection can represent a rescue therapy after an acute hepatic damage in immunocompetent rats.

BACKGROUND AND AIM: Tissue homeostasis and turnover require reserve stem proliferating cells. Several studies performed on immunodeficient animals have suggested a degree of plasticity by the hematopoietic stem cell compartment that may represent source for liver regeneration. We sought to explore the hepatic differentiation potential of hematopoietic stem cells from human cord blood, after toxic liver damage induced by allyl-alcohol in immunocompetent rats. MATERIALS AND METHODS: Wistar rats were divided into groups (A) allyl-alcohol intraperitoneal injection with hematopoietic stem cell intraperitoneal infusion at 1 day and sacrifice 3 days later; (B) stem cell injection and sacrifice 3 days later; (C) allyl-alcohol infusion and sacrifice 4 days later; and (D) sacrifice without any treatment. Livers, spleens, and bone marrows were analysed for human stem cells using flow-cytometry; livers were also tested by histology and immunohistochemistry to study the pattern of hepatic regeneration after damage and human stem cell conversion into hepatocyte-like cells, respectively. RESULTS: Flow-cytometry revealed selective recruitment of human hematopoietic stem cells by damaged livers (group A) compared with control group B. In addition, liver damage was reduced in animals treated with stem cells. Immunohistochemistry demonstrated that human stem cells could convert hepatic cells. CONCLUSIONS: Our study demonstrated that hematopoietic stem cells selectively recruited by injured livers can contribute to hepatic regeneration after acute toxic damage in immunocompetent recipients.

Catholic university experience with molecular adsorbent recycling system in patients with severe liver failure.

BACKGROUND AND AIM: Molecular adsorbent recycling system (MARS) treatment is able to remove both hydrosoluble and small- and medium-sized lipophilic toxins. MARS plays an important role in modifying liver failure complications, such as hepatorenal syndrome and hepatic encephalopathy. We sought to evaluate the clinical efficacy and safety of a MARS device in a consecutive series of hepatic failure patients. MATERIALS: Twenty patients with acute liver failure, transplantation failure, or acute on chronic liver failure fulfilled the inclusion criteria of total bilirubin > or =10 mg/dL and at least one of the following: hepatic encephalopathy (HE) > or =II grade, hepatorenal syndrome (HRS) for chronic patients or total bilirubin > or =5 mg/dL and HE > or =I grade for acute patients. RESULTS: MARS was able to reduce cholestatic parameters and improve neurologic status and renal function parameters in all treated patients. We also observed an improvement in the 3-month survival rate compared to the expected outcome in patients with MELD scores between 20 and 29, as well as 30 and 39. CONCLUSIONS: Based on these results, we confirm the safety and clinical efficacy of MARS treatment, with the best results in patients with MELD score of 20 to 29. Further studies are necessary to confirm whether this treatment is able to modify patient outcomes and prognosis.

Analgesic, antiulcer, antithrombotic drugs and organ damage: a population-based case-control study.

AIM: Oral medication is of paramount importance for pain treatment. Analgesics, antiulcer (AUDs) and antithrombotic drugs (ATDs) are often coprescribed in elderly people. Non-steroidal anti-inflammatory drugs (NSAIDs) require AUDs to lower the risk of peptic ulcer, and potentially interfere with ATDs. The aim of this study was to quantify the prevalence of NSAID use in patients with gastrointestinal, cardiac or kidney damage in the year 2013, compared to the general population. METHODS: We performed a population-based case-control study in the Republic of San Marino to evaluate the Odds-Ratios for upper gastrointestinal damage (gastroduodenal ulcers and/or erosions, GUE), ischemic heart disease (IHD), heart failure (HF), and renal function impairment (assessed using the CKD-EPI formula), in people who had taken AUDs, ATDs, or NSAIDs in the previous 90 days, versus people who had not taken such drugs in the same period of time. RESULTS: We found that AUDs decreased the OR for GUE (OR: 0.762; CI:0.598-0.972), while ATDs and NSAIDs increased the risk (OR: 1.238 and CI: 0.935-1.683; OR:1.203 and CI:0.909-1.592, respectively). NSAIDs seemed to increase the risk of IHD, although this was not statistically significant (OR=1.464; CI=0.592-3.621). AUDs and ATDs significantly increased the risk of renal function impairment (OR=1.369 and CI=1.187-1.579; OR=1.818 and CI=1.578-2.095, respectively), while this effect was not observed for NSAIDs. CONCLUSION: NSAIDs may induce gastrointestinal and cardiovascular damage, not only by themselves, but also when used concomitantly with common medications such as AUDs or ATDs, due to additive and/or synergistic effects. We performed a "pragmatic" analysis of the association of organ damage with use of NSAIDs/AUDs/ATDs, including patient age, treatment duration and dose, to allow for an immediate application of our findings to everyday clinical practice.

Stem cells: new tools in gastroenterology and hepatology.

Stem cells play a key role in tissue homeostasis and renewal after damage, so learning more about them may become a sort of 'Pandora's box', which when opened will make it possible to clarify the nature and the pathophysiology of several human diseases and to find new treatments for pathologies, such as cancers, degenerative, autoimmune and genetic disorders, that are currently untreatable. The characteristics of the gastrointestinal tract and of the liver, in terms of genesis and regeneration and their special relationship with the haemolymphopoietic system, allow stem cell research to outline interesting therapeutic perspectives in these fields. We aim to summarize the knowledge acquired on gastrointestinal and hepatic stem cell biology, focusing attention on the issues that remain to be addressed, and to present the main perspectives of treatment offered by these 'new tools' in gastroenterology and hepatology.

A human umbilical cord stem cell rescue therapy in a murine model of toxic liver injury.

BACKGROUND: Several studies have demonstrated that bone marrow contains a subpopulation of stem cells capable of participating in the hepatic regenerative process, even if some reports indicate quite a low level of liver repopulation by human stem cells in the normal and transiently injured liver. AIMS: In order to overcome the low engraftment levels seen in previous models, we tried the direct intraperitoneal administration of human cord blood stem cells, using a model of hepatic damage induced by allyl alcohol in NOD/SCID mice. METHODS: We designed a protocol based on stem cell infusion following liver damage in the absence of irradiation. Flow cytometry, histology, immunohistochemistry and RT-PCR for human hepatic markers were performed to monitor human cell engraftment. RESULTS: Human stem cells were able to transdifferentiate into hepatocytes, to improve liver regeneration after damage and to reduce the mortality rate both in both protocols, even if with qualitative and quantitative differences in the transdifferentiation process. CONCLUSIONS: We demonstrated for the first time that the intraperitoneal administration of stem cells can guarantee a rapid liver engraftment. Moreover, the new protocol based on stem cell infusion following liver damage in the absence of irradiation may represent a step forward for the clinical application of stem cell transplantation.

Cell-based therapy for liver diseases.

Although liver transplantation has become standard therapy in the treatment of patients with liver failure, several problems should be considered in the management of these patients. Other approaches have been proposed, in particular cellular-based procedures. Isolated hepatocytes may be used instead of whole organ transplantation or integrated within the bioartificial devices, in order to replace the missing synthetic and metabolic liver functions. Moreover patient's own hepatocytes may be ex vivo genetically modified to provide the function of a mutant gene. However, new cell sources alternative to adult hepatocytes are actually under investigation, on the basis of recent advances in the field of liver repopulation. Xenogenic primary cells, human hepatoma cells, immortalized hepatocytes and stem cells have been testing in several experiments, even if up to now none of them represent a "gold-standard" for cell-based treatment of liver diseases. In the next future, it is possible that different clinical situations will require different therapeutic approaches, that will be finally defined from the concomitant advances in the development of artificial devices and liver cell biology.

Chronic anisakidosis presenting with intestinal intussusception.

OBJECTIVE: Anisakidosis is a parasitic infection caused by the ingestion of row or uncooked fish, containing larval nematodes from the Anisakidae family. Intestinal anisakidosis represents about 4% of all cases, the majority being localized in the small bowel, with rare colonic involvement. Here we present an infrequent case of chronic anisakidosis, presenting with intestinal intussusception. CASE REPORT: A 52 years old woman, chronically treated with immunosuppressants, presented to our Institution with acute abdominal pain and vomiting, due to colocolic intussusception. Colonoscopy successfully reduced the intussusception and revealed the presence of a voluminous colonic submucosal mass, near the hepatic flexure. Therefore, the patient underwent laparoscopic right hemicolectomy. The diagnosis of anisakidosis was made when the histological examination of the surgical specimen revealed the infestation of the intestinal wall by a nematode of the Anisakidae family, with an intense erosive-inflammatory adjacent reaction.