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Biomedical subjects

C De Simone

Publications and source records attributed to C De Simone.

At least 19 recordsLinked to original sources
PubMed2006

The VSL#3 probiotic formula induces mucin gene expression and secretion in colonic epithelial cells.

Several studies have stressed the importance of the microbiota in the maintenance of the gastrointestinal epithelium. Administration of probiotic bacteria, supplements composed of microbiota constituents, was previously shown to diminish symptoms in patients suffering from inflammatory bowel diseases. This raises the possibility that probiotics may play an active role in enhancing the intestinal barrier at the mucosal surface. In this study, we investigated whether the clinically tested VSL#3 probiotic formula and/or its secreted components can augment the protective mucus layer in vivo and in vitro. For in vivo studies, Wistar rats were orally administered the probiotic mixture VSL#3 on a daily basis for seven days. After treatment, basal luminal mucin content increased by 60%. In addition, we exposed isolated rat colonic loops to the VSL#3 probiotic formula, which significantly stimulated colonic mucin (MUC) secretion and MUC2 gene expression; however, MUC1 and MUC3 gene expression were only slightly elevated. The effect of the VSL#3 mucin secretagogue was also tested in vitro by use of LS 174T colonic epithelial cells. In contrast to the animal studies, cultured cells incubated with VSL#3 bacteria did not exhibit increased mucin secretion. However, the bacterial secreted products contained in the conditioned media stimulated a remarkable mucin secretion effect. Among the three bacterial groups (Lactobacilli, Bifidobacteria, and Streptococci) contained in VSL#3, the Lactobacillus species were the strongest potentiator of mucin secretion in vitro. A preliminary characterization of the putative mucin secretagogue suggested that it was a heat-resistant soluble compound, which is not sensitive to protease and DNase treatment. These findings contribute to a better understanding of the complex and beneficial interaction between colonic epithelial cells and intestinal bacteria.

Animals↗
PubMed2006

The CD40/CD40 ligand system is expressed in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis spectrum.

BACKGROUND: Erythema multiforme (EM) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) are determined by a dysregulation of cellular immunity. OBJECTIVES: To evaluate the effector role of cellular immunity and the involvement of the CD40/CD40 ligand (CD40L) system in the pathogenesis of EM and SJS/TEN. METHODS: Biopsy specimens from eight patients with EM and six with SJS/TEN were stained for immunohistochemical examination using the alkaline phosphatase/antialkaline phosphatase method. The monoclonal antibodies used included those to CD1a, CD4, CD8, CD40, CD40L, CD68, Fas, Fas ligand (FasL) and myeloperoxidase. RESULTS: The cellular infiltrate in both EM and SJS/TEN lesions was composed mainly of T lymphocytes and CD68+ macrophages. We also detected large amounts of neutrophils. Fas and FasL were very highly expressed in SJS and TEN, but weakly in EM. CD40 staining was strong in all tissue sections; there were numerous CD40L+ cells in SJS/TEN but much fewer in EM. CONCLUSIONS: Activated T lymphocytes and macrophages, but also neutrophils, are presumably the main triggers of mucocutaneous damage in the SJS/TEN disease spectrum. The Fas/FasL system is significantly expressed in SJS/TEN lesions, but not in EM, where this apoptotic pathway presumably does not play a pivotal role in the epidermal damage. We suggest that the CD40/CD40L system may represent an important pathway of induction of SJS/TEN lesions, while in EM it would contribute to the immunoinflammation only as a second-line mechanism.

Adult↗
PubMed2006

Expression of cytokines and chemokine receptors in the cutaneous lesions of erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis.

BACKGROUND: Erythema multiforme (EM) and Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are caused by a dysregulation of cellular immunity. OBJECTIVES: To evaluate further the potential role of certain cytokines and chemokine receptors in cutaneous lesions of patients affected by EM and SJS/TEN and to establish whether such diseases are polarized preferentially towards a T-helper (Th) 1 or Th2 pattern. METHODS: Biopsy specimens from eight patients with EM, six with SJS/TEN and three healthy controls were stained for immunohistochemical examination using the alkaline phosphatase-antialkaline phosphatase method. The monoclonal antibodies used included those to tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-2, IL-5, IL-13, receptor 3 for C-C chemokines (CCR3), receptor 3 for C-x-C chemokines (CXCR3) and CXCR4. RESULTS: The SJS/TEN specimens showed significantly higher expression of all the cytokines and chemokine receptors (except CXCR3) tested than the EM specimens. Both lesional series showed significantly higher expression of all the receptors tested than the healthy control specimens, with the sole exception of a lower expression of CCR3 in EM specimens. Comparison between molecules associated with a Th1 or Th2 response revealed a predominance of Th1 response in EM and no significant imbalance between Th1 and Th2 in SJS/TEN. CONCLUSIONS: We have provided further evidence that TNF-alpha is strongly expressed in SJS/TEN lesions and therefore it may be involved in the epidermal necrosis featured in such diseases. IFN-gamma may play an important role both in EM and SJS/TEN. IL-2, IL-5 and IL-13 may contribute to the cutaneous immunoinflammation in these diseases. Chemokine receptors may be involved strongly in the recruitment of inflammatory cells in lesional skin. In our cases we found a sharp polarization towards a Th1 pattern in EM, while the SJS/TEN lesions showed a mixed Th1/Th2 pattern.

Adult↗
PubMed2006

Long-term prophylaxis with intermediate-purity factor VIII concentrate (Haemate P) in a patient with type 3 von Willebrand disease and recurrent gastrointestinal bleeding.

Prophylaxis with von Willebrand factor (VWF)-containing concentrates is considered to be a potential approach for patients with von Willebrand disease (VWD) and severe bleeding tendency. We report the case of a 57-year-old man with type 3 VWD and a history of recurrent melaena. Bleeding frequency and severity had progressively increased and the patient showed chronic anaemia and persistent haemoglobin in the stools. Endoscopic examinations revealed multiple vascular mucosal abnormalities (MVA) of the stomach and large bowel. Photocoagulation of some actively bleeding lesions and octreotide did not significantly affect his clinical conditions: six red cell transfusions and >400 000 IU of intermediate-purity factor VIII (FVIII) concentrate (Haemate P) on-demand were needed during 2002. Prophylaxis with Haemate P 40 IU kg(-1) (102 IU kg(-1) VWF:RCo) thrice weekly was associated with improvement of his mean haemoglobin levels, cessation of clear-cut melaena and red cell transfusions and reduction of total Haemate P requirements (-20% over 2003-04). Prophylaxis with Haemate P is still ongoing without any adverse event over a 30-month period. Clinical course and pharmacokinetic evaluations led to administer Haemate P each 72-96 h. Possible vascular complications were excluded by a careful clinical follow up, as the patient suffered from arterial hypertension and diabetes mellitus; thrombophilic abnormalities were previously excluded and no signs of abnormal coagulation activation or FVIII:C levels >150% were detected thereafter. Long-term prophylaxis with Haemate P has been shown to be safe, effective (also in terms of quality of life) and cost saving in this patient with severe gastrointestinal bleeding due to MVA and VWD.

Factor VIII↗
PubMed2005

Oral probiotic administration induces interleukin-10 production and prevents spontaneous autoimmune diabetes in the non-obese diabetic mouse.

AIMS/HYPOTHESIS: Recent observations suggest the involvement of the gastrointestinal tract in the pathogenesis of islet autoimmunity. Thus, the modulation of gut-associated lymphoid tissue may represent a means to affect the natural history of the disease. Oral administration of probiotic bacteria can modulate local and systemic immune responses; consequently, we investigated the effects of oral administration of the probiotic compound VSL#3 on the occurrence of diabetes in non-obese diabetic (NOD) mice. METHODS: VSL#3 was administered to female NOD mice three times a week starting from 4 weeks of age. A control group received PBS. Whole blood glucose was measured twice a week. IFN-gamma and IL-10 production/expression was evaluated by ELISA in culture supernatants of mononuclear cells isolated from Peyer's patches and the spleen, and by real-time PCR in the pancreas. Insulitis was characterised by immunohistochemistry and histomorphometric studies. RESULTS: Early oral administration of VSL#3 prevented diabetes development in NOD mice. Protected mice showed reduced insulitis and a decreased rate of beta cell destruction. Prevention was associated with an increased production of IL-10 from Peyer's patches and the spleen and with increased IL-10 expression in the pancreas, where IL-10-positive islet-infiltrating mononuclear cells were detected. The protective effect of VSL#3 was transferable to irradiated mice receiving diabetogenic cells and splenocytes from VSL#3-treated mice. CONCLUSIONS/INTERPRETATION: Orally administered VSL#3 prevents autoimmune diabetes and induces immunomodulation by a reduction in insulitis severity. Our results provide a sound rationale for future clinical trials of the primary prevention of type 1 diabetes by oral VSL#3 administration.

Adoptive Transfer↗
PubMed2005

Atypical multifocal cutaneous leishmaniasis in an immunocompetent patient treated by liposomal amphotericin B.

Multifocal cutaneous leishmaniasis (MCL) is an extremely rare disease in South Europe, and it mainly affects immunosuppressed patients. We report a case of MCL in an immunocompetent patient affected by type II diabetes mellitus that clinically presented with three large ulcers on the legs with a non-linear distribution and several months later with an erythematous-crusty lesion on the left cheek. Diagnosis of leishmaniasis due to Leishmania infantum was formulated by PCR analysis. Given the diffuse and wide lesions, the unresponsiveness to previous local and systemic treatments, a parenteral i.v. therapy with liposomal amphotericin B at a dosage of 3mg/kg/day for 5 days was started and then repeated on the 14th and 21st days, leading to a clear improvement in the clinical picture. The different clinical expression and the evolution of leishmaniasis depend on both the parasite subtype and the host's immunity status. L. infantum manifests with an atypical clinical feature more frequently than other species. The differential diagnosis for multiple ulcers must include several skin diseases, such as cutaneous TBC, bacterial ulcers, traumatic ulcers, deep mycoses, and sarcoidosis. However, an MCL should always be considered in subjects coming from endemic areas. In our case, the multifocality, the size of the lesions and the unresponsiveness to other treatment indicate a short course treatment with liposomal B amphotericin that proved to be a suitable alternative to traditional drugs used in MCL.

Aminoglycosides↗
PubMed2003

Lichens as polycyclic aromatic hydrocarbon bioaccumulators used in atmospheric pollution studies.

The aim of this work has been to determine the possibility of using lichens as polycyclic aromatic hydrocarbon (PAH) bioaccumulators for the evaluation of atmospheric pollution in the city of Rieti. A lichen sample collected in a remote unpolluted area was divided into 18 sub-samples. These were collocated in nine different stations in the city of Rieti and every 5 months the PAH concentrations were determined. Only phenanthrene, anthracene, fluoranthene, pyrene and chrysene were found at concentrations over the limit of quantification. In the meantime a continuous increase of their concentrations was observed.

Air Pollutants↗
PubMed2002

A review of studies on the effects of ultraviolet irradiation on the resistance to infections: evidence from rodent infection models and verification by experimental and observational human studies.

Recent studies on the immunosuppressive effects of ultraviolet radiation (UVR) and the related resistance to infections in rodents and humans are presented. The waveband dependency of trans-to-cis isomerisation of urocanic acid in the stratum corneum and the role of DNA damage in UVR-induced erythema and immunosuppression were investigated to further elucidate the underlying mechanisms. Furthermore, human experimental studies on UVR-induced immunomodulation were performed. It appeared that the doses needed to suppress various immune parameters in humans (e.g. NK activity, contact hypersensitivity) were higher than those needed in experiments in rodents. Still, extrapolation of experimental animal data to the human situation showed that UVR may impair the resistance to different systemic infections at relevant outdoor doses. In observational human studies we aimed to substantiate the relevance of UVR for infections in humans. It was shown that sunny season was associated with a slightly retarded but clinically non-relevant antibody response to hepatitis B vaccination. Furthermore, sunny season appeared to be associated with a small decline in the number of CD4+ T-helper cells in a cohort of HIV-infected persons and a higher recurrence of herpes simplex and herpes zoster in a cohort of renal transplant recipients. However, in a study among young children a higher exposure to solar UVR was associated with a lower occurrence of upper respiratory tract symptoms. As disentangling the effects of UVR from other relevant factors is often impossible in observational studies, concise quantitative risk estimations for the human situation cannot be given at present.

Animals↗
PubMed2002

Squamous cell carcinoma arising in a venous ulcer as a complication of the Klippel-Trenaunay syndrome.

Klippel-Trenaunay (KT) syndrome is a vascular malformation characterized by a port-wine stain, varicose veins and hypertrophy of the affected limb. Ulceration is considered an uncommon complication of KT syndrome and occurrence of skin cancer has been previously reported only in one case. We observed a case of KT syndrome in a 48-year-old woman who developed a large ulcer and a squamous cell carcinoma on the affected leg.

Carcinoma, Squamous Cell↗
PubMed2002

Dermatomyositis in 132 patients with different clinical subtypes: cutaneous signs, constitutional symptoms and circulating antibodies.

We retrospectively studied 132 patients with dermatomyositis; 84 had idiopathic, 30 paraneoplastic, 5 juvenile and 13 amyopathic forms of the disease. The commonest features were macular erythema, heliotropic erythema and Gottron's papules. Flagellate erythema occurred in 5% of patients with idiopathic dermatomyositis and correlated with the disease activity. Necrotic lesions were also found in this group of patients but did not always signal malignancy. The prevalence of malignancy was high (23%). Raynaud's phenomenon occurred in 10.6% of patients, also in those with malignancy. Dysphagia, interstitial lung disease and arthralgias affected 20%, 8% and 40% of patients, respectively. Anti-Jo-1 antibodies were found in 5% of patients with idiopathic dermatomyositis and low titre ANA in 1/3 of patients. ANA did not correlate with the disease activity. We confirmed the data from the literature, but no cutaneous sign, constitutional symptom or circulating antibody was found marking a particular subtype of the disease.

Adolescent↗
PubMed2002

[Investigation on BLS among public hospital physicians in Abruzzo].

BACKGROUND: The aim of this study is to determine the proportion of public hospital physicians in Abruzzo capable of performing basic life support manoeuvres, according to the latest guidelines. METHODS: A questionnaire was formulated, in order to investigate whether the persons interviewed 1) had ever performed a cardio-pulmonary resuscitation; 2) had ever taken any BLS courses involving dedicated dummies; 3) believed to be competent in performing cardio-pulmonary resuscitation correctly and if affirmative, the physician was asked to answer three further questions to verify the level of competence. The questionnaire was to be filled in at the proper working place without the aid of books or other material. RESULTS: Of the 1540 public hospital physicians contacted, 57.6% had participated in cardiopulmonary resuscitation manoeuvres, while only 30% had practised on dedicated dummies. Nevertheless, 69.5% believed to be able to perform the BLS techniques correctly. Of the latter, merely 18% answered all three additional questions correctly. CONCLUSIONS: Cardio-pulmonary arrest is the emergency during which the timeliness of the first resuscitation manoeuvres and their correct performance are the decisive factors for a successful outcome. Without attending regular courses, qualified to teach the proper techniques in depth and recall the acquired procedures, the efficacy of BLS techniques risk to fall below a level of acceptance. Therefore, in the emergency field, it is essential to guarantee a continued training.

Cardiopulmonary Resuscitation↗
PubMed2001

Circulating neutrophils exhibit enhanced apoptosis associated with mitochondrial dysfunctions after surgery under general anaesthesia.

BACKGROUND: Evidence suggests that apoptosis plays a main role in the postoperative changes detected in the polymorphonuclear neutrophil (PMN) population. Furthermore, recent studies have demonstrated that mitochondrial alterations constitute critical events of the apoptotic cascade. In this study we investigated whether apoptosis among neutrophils taken from patients undergoing surgical trauma could be associated with perturbation of mitochondrial transmembrane potential (deltapsim) and/or exaggerated production of mitochondrial reactive oxygen species (ROS). METHODS: Twenty-seven patients undergoing elective surgery under general anaesthesia were enrolled in the study. Peripheral blood samples were drawn one day before the operation and at 12 and 24 h after surgery. Apoptosis rate was assessed by staining neutrophils with 7-amino-actinomycin D (7-AAD) and by analysis by a FACScan flow cytometer. In order to evaluate deltapsim, cells were exposed to 3,3-dihexyloxacarbocyanine iodide [DiOC6(3)]; intracellular ROS was measured by means of hydroethidine (HE) and 2,7-diclorofluorescein diacetate (DCFH-DA), followed by analysis on a cytofluorometer. RESULTS: At 12 h following surgery we observed a significantly (P<0.05) increased frequency of apoptotic PMNs compared to that preoperatively (30.79+/-3.68% vs 7.40+/-0.69%). At this same time-point, the rate of neutrophils stained with HE, DCFH-DA and [DiOC6(3)] were significantly (P<0.05) higher compared to baseline (51.05+/-5.44%, 50.58+/-5.84% and 55.31+/-4.33% vs 20.17+/-2.38%, 19.59+/-2.03 and 25.43+/-2.71% respectively). Overall measurements returned to the preoperative values 24 h after surgery. CONCLUSION: These data suggest that surgery under general anaesthesia triggers in the immediate postoperative period pathways of PMN accelerated apoptosis associated with significant alterations in mitochondrial function.

Aged↗
PubMed2001

Urocanic acid isomers in patients with non-melanoma skin cancer.

BACKGROUND: Cis-urocanic acid (cis-UCA), formed from the naturally occurring trans-isomer in the epidermis on ultraviolet (UV) radiation, initiates some of the changes leading to UV-induced immunosuppression, but its role in cutaneous carcinogenesis has not been fully investigated. OBJECTIVES: To measure the concentration of UCA isomers in the photoexposed and non-photoexposed skin of patients with multiple non-melanoma skin cancer (NMSC), enrolled in different periods of the year, in comparison with control subjects. PATIENTS/METHODS: UCA isomers were determined by high-performance liquid chromatography analysis in samples from the outer arm (photoexposed site) and buttock (non-photoexposed site) obtained from 20 patients and 19 controls during the winter period (October to April), and from five patients and 11 controls during the summer period (June to September). RESULTS: In the winter months, no difference was found between patients and controls in the concentration of UCA or the percentage of cis-UCA in either site. In the summer months, the percentage of cis-UCA in the buttock of patients and controls was similar but it was significantly higher in the arm of the controls (42%) than in the patients (17%). CONCLUSIONS: We conclude that different behaviour regarding sun exposure is the most likely explanation for these results, and that the concentration of UCA and its isomers does not reflect a tendency for individuals to develop NMSC.

Adult↗