Biomedical subjects

M D'Amato

Publications and source records attributed to M D'Amato.

At least 19 recordsLinked to original sources

PubMed2005

Immune control of food intake: enteroendocrine cells are regulated by CD4+ T lymphocytes during small intestinal inflammation.

BACKGROUND AND AIMS: Gastrointestinal inflammation reduces food intake but the biological mechanisms explaining suppressed feeding during inflammation are unknown. We have used a model of upper gut infection (Trichinella spiralis in the mouse) to study the effect of inflammation on food intake, and explored the role of a key enteroendocrine cell (EEC) in the regulation of feeding by the immune response. METHODS: Food intake of NIH mice infected with the intestinal nematode Trichinella spiralis was measured. Duodenal cholecystokinin (CCK) cells were counted. Plasma CCK was measured. Infected mice were treated with a specific CCK1 receptor antagonist, and food intake reassessed. The influence of the immune response on food intake and CCK was mechanistically examined by treating mice with CD4 or mast cell neutralising antibodies. The role of the T helper 2 response was further explored in mice genetically deficient for interleukin (IL)-4, IL-13, or IL-4Ralpha (receptor alpha subunit). RESULTS: Food intake of infected mice was significantly reduced at the temporal peak of intestinal inflammation. CCK expressing EEC were upregulated in infected mice, and plasma CCK levels were increased. A CCK1 receptor antagonist restored the food intake of infected mice to a significant degree. Furthermore, suppression of food intake was completely abolished in the absence of CD4+ T lymphocytes or IL-4Ralpha. CONCLUSIONS: The data show for the first time that intestinal inflammation results in reduced food intake due to upregulation of CCK. Moreover, following infection, food intake and CCK expressing cells are under the specific control of CD4+ T-cells, via release of IL-4 and IL-13.

Animals↗

PubMed2005

Homogeneity and stability study of the candidate reference material Adamussium colbecki for trace elements.

The preparation of a new candidate certified reference material (CRM) for trace elements based on the antarctic bivalve Adamussium colbecki(IRMM 813) was carried out by the Istituto Superiore di Sanità(ISS, Rome, Italy) in cooperation with the Institute for Reference Materials and Measurements, Joint Research Centre of the European Commission (EC-JRC-IRMM), in the frame of the Italian National Programme of Research in Antarctica (Programma Nazionale di Ricerca in Antartide, PNRA). Samples were collected at Terra Nova Bay (Ross Sea) during the 2000-2001 expedition in Antarctica. The preparation of a material suitable for certification was performed by the EC-JRC-IRMM. Measurements for homogeneity and short-term stability tests were carried out by ISS. The elements selected for the certification project were As, Cd, Cu, Cr, Fe, Mn, Ni and Zn. For the above-mentioned tests, the determination of the elements of interest was performed on samples mineralised by microwave-assisted acid digestion. The analytical techniques employed to this end were inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma dynamic reaction cell quadrupole mass spectrometry (ICP-DRC-Q-MS). The candidate material was shown to be fit for purpose with regard to homogeneity and short-term stability, thus allowing the following phases of the certification project to be undertaken, in the first place the selection of expert laboratories for the accomplishment of the certification campaign.

Animals↗

PubMed2005

CARD15/NOD2 polymorphisms do not explain concordance of Crohn's disease in Swedish monozygotic twins.

BACKGROUND: CARD15/NOD2 polymorphisms are associated with Crohn's disease. There is a high concordance for disease and disease phenotype in monozygotic twin pairs with Crohn's disease. AIM: We studied CARD15/NOD2 polymorphisms in a Swedish, population-based cohort of monozygotic twins with Crohn's disease to assess whether these variants explain disease concordance. SUBJECTS AND METHODS: Twenty-nine monozygotic twin pairs (concordant n=9, discordant n=20) with Crohn's disease and 192 healthy controls were investigated for the CARD15/NOD2 variants Arg702Trp, Gly908Arg and Leu1007fsinsC. RESULTS: CARD15/NOD2 mutations were found in 5/38 (13%) twins with Crohn's disease, corresponding to a total allele frequency of 6.6%. Only 2/9 concordant twin pairs carried any of the variants and the remaining seven were wild type genotype. The total allele frequency was 4.4 times higher (95% confidence interval 1.0-21.5, p=0.06) in concordant twins than in discordant ones, 11.1% versus 2.5%. In healthy controls the total allele frequency was 2.6%. CONCLUSIONS: CARD15/NOD2 polymorphisms contribute but do not alone explain concordance of Crohn's disease in monozygotic twins and, at least in a Swedish population, other polymorphisms are required. The low occurrence of CARD15/NOD2 mutations in the study and other Northern European populations suggests that these variants are of less importance in Northern Europe.

Adolescent↗

PubMed2005

Environmental risk factors and allergic bronchial asthma.

The prevalence of allergic respiratory diseases such as bronchial asthma has increased in recent years, especially in industrialized countries. A change in the genetic predisposition is an unlikely cause of the increase in allergic diseases because genetic changes in a population require several generations. Consequently, this increase may be explained by changes in environmental factors, including indoor and outdoor air pollution. Over the past two decades, there has been increasing interest in studies of air pollution and its effects on human health. Although the role played by outdoor pollutants in allergic sensitization of the airways has yet to be clarified, a body of evidence suggests that urbanization, with its high levels of vehicle emissions, and a westernized lifestyle are linked to the rising frequency of respiratory allergic diseases observed in most industrialized countries, and there is considerable evidence that asthmatic persons are at increased risk of developing asthma exacerbations with exposure to ozone, nitrogen dioxide, sulphur dioxide and inhalable particulate matter. However, it is not easy to evaluate the impact of air pollution on the timing of asthma exacerbations and on the prevalence of asthma in general. As concentrations of airborne allergens and air pollutants are frequently increased contemporaneously, an enhanced IgE-mediated response to aeroallergens and enhanced airway inflammation could account for the increasing frequency of allergic respiratory allergy and bronchial asthma. Pollinosis is frequently used to study the interrelationship between air pollution and respiratory allergy. Climatic factors (temperature, wind speed, humidity, thunderstorms, etc) can affect both components (biological and chemical) of this interaction. By attaching to the surface of pollen grains and of plant-derived particles of paucimicronic size, pollutants could modify not only the morphology of these antigen-carrying agents but also their allergenic potential. In addition, by inducing airway inflammation, which increases airway permeability, pollutants overcome the mucosal barrier and could be able to "prime" allergen-induced responses. There are also observations that a thunderstorm occurring during pollen season can induce severe asthma attacks in pollinosis patients. After rupture by thunderstorm, pollen grains may release part of their cytoplasmic content, including inhalable, allergen-carrying paucimicronic particles.

Air Pollutants↗

PubMed2005

Direct and prolonged exposure to dogs does not influence the degree of skin prick test positivity to dog allergen.

BACKGROUND: The relationship between pet ownership and the risk of developing allergic sensitization to pet allergens is still controversial. We assessed the possible effect of direct exposure to dog allergen on skin reactivity in dog-sensitized patients. METHODS: We studied, in a case-control trial, 116 adults sensitized to dog allergens (55 with a dog at home for at least 10 years and 61 without it). The degree of response was assessed by skin prick test, performed in quadruplicate with three concentrations of allergenic extract: A (1:20 w/v), B (1:200 w/v) and C (1:2000 w/v). The mean diameter of each wheal was assessed using a visilog image analysis software. RESULTS: No significant difference between the two groups in the wheal diameters induced by the three concentrations of dog allergen could be demonstrated. CONCLUSION: The results of this study suggest that direct dog exposure in adults with respiratory allergy is not associated with greater cutaneous response to dog allergens, as compared to non exposed subjects.

Adolescent↗

PubMed2005

Safety of celecoxib in patients with adverse skin reactions to acetaminophen (paracetamol) and other non-steroidal anti-inflammatory drugs.

BACKGROUND: Acetaminophen (paracetamol-P) is a widely used analgesic-antipyretic drug with no anti inflammatory effects and its rate of adverse hypersensitivity reactions is very low. On the contrary non-steroidal anti-inflammatory drugs (NSAIDs) are commonly involved in side effects. Celecoxib (CE) is a novel drug, with high selectivity and affinity for COX-2 enzyme. OBJECTIVE: We evaluated the tolerability of CE in a group of patients with documented history of adverse cutaneous reactions to P and to classic NSAIDs. METHODS: We studied 29 patients with hypersensitivity to P and classic NSAIDs. The diagnosis of P-induced skin reactions was based on in vivo challenge. The placebo was blindly administered at the beginning of each challenge. After three days, a cumulative dosage of 200 mg of CE in refracted doses was given. After 2-3 days, a single dose of 200 mg was administered. All patients were observed for 6 hours after each challenge, and they were controlled again after 24 hours to exclude delayed reactions. The challenge was considered positive if one or more of the following appeared: erythema, rash or urticaria-angioedema. RESULTS: No reaction was observed with placebo and twenty eight patients (96.5 %) tolerated CE. Only one patient developed a moderate angioedema of the lips. CONCLUSION: Only one hypersensitivity reaction to CE was documented among 29 P-intolerant patients. Thus, we conclude that CE is a reasonably safe alternative which can be used in subjects who do not tolerate P.

Acetaminophen↗

PubMed2005

Sputum induction in corticosteroid-dependant asthmatics: risks and airway cellular profile.

Sputum induction with nebulized hypertonic saline is increasingly being used to evaluate airway inflammation. We investigated the procedure-associated risk in 16 asthmatics that were still symptomatic despite on high doses of regular corticosteroid (CS) therapy (7 on daily inhaled CS > or = 800 microg budesonide or equivalent; 9 on additional daily oral CS) and their sputum cellular profile. For comparison, 12 mild stable asthmatics and 10 normal healthy subjects were included. All subjects inhaled 3%, 4% and 5% hypertonic saline sequentially via ultrasonic nebulizer as a means to induce sputum. Maximal percentage fall of Forced Expiratory Volume on One Second (FEV1) during sputum induction was significantly greater in CS-dependent asthmatics (median % [IQR]: 16.0 [11.0-32.3]) than in mild asthmatics (5.3 [4.2-10.8], p = 0.002] and in normal subjects (4.6 [3.4-6.4]), p = 0.0001). The maximal percentage FEV1 fall was inversely correlated with baseline FEV1 (Rs= -0.69; p < 0.0001). Compared to mild asthmatics, induced sputum from CS-dependant asthmatics had proportionately fewer eosinophils (2.2 [0.8-7.0] versus 23.3% [10.7-46.3], p = 0.003) and greater neutrophils (64.2 [43.9-81.2] versus 28.7 [19.0-42.6], p = 0.009). Sputum neutrophils showed a significant inverse correlation to FEV1 (Rs = -0.51, p = 0.01). We concluded that sputum induction using nebulized hypertonic saline should be performed with caution in CS-dependant asthmatics. The airway cellular profile observed suggests that the immunopathology underlying CS-dependant asthmatics may be different or a consequence of CS therapy.

Adrenal Cortex Hormones↗

PubMed2004

Summary of recommendations for the design of clinical trials and the registration of drugs used in the treatment of asthma.

With new drugs being introduced to treat asthma it is timely to review criteria that can be used to assess efficacy in clinical trials. Anti-asthma drugs are classified into symptoms-modifying, symptom preventers and disease modifying agents. Attention is drawn to the types of experimental evidence required in preclinical studies to support further clinical development of a new therapy. Clinical trials demand careful selection of patients to maximise the strength of the efficacy signal according to the type of trial being designed. While provocation tests are useful in suggesting efficacy, negative tests do not necessarily indicate lack of anti-asthma activity. Therapeutic trial designs need to take account of duration of treatment, dose-response relationships and confirmatory trials. Outcome measures include symptoms, lung function, reduction in concomitant medication, exacerbations, quality of life and measures of inflammation. Interpretation of results need to include the clinical relevance of any changes as well as statistical significance. Special consideration needs to be given to the evaluation of drugs for acute severe asthma, asthma in children and older people, co-morbidity such as rhinitis, and inhaler devices. As with all drugs introduced into practice, careful attention needs to be paid to both short- and long-term safety.

Acute Disease↗

PubMed2004

Malassezia enhances natural killer cell-induced dendritic cell maturation.

Human natural killer (NK) cells can induce cell death in autologous dendritic cells (DCs), though an interaction between these two cell types can also lead to a reciprocal activation. We have recently shown cell contact between NK cells and DCs in vivo, in Malassezia-induced lesional skin of patients with atopic eczema, where the yeast acts as an allergen although it is part of the normal skin microflora. Here we characterize the interaction of human NK cells and monocyte-derived DCs (MDDCs) by using an in vitro system where short-term activated polyclonal NK cells are cocultured with autologous, immature, Malassezia-stimulated or lipopolysaccharide-matured MDDCs. We found that the number of CD83(+) MDDCs increased in the immature and Malassezia-stimulated MDDCs upon coculture with NK cells, while an increased number of CD86(+) cells was detected in the Malassezia-stimulated MDDCs. NK cell-MDDC interaction induced the production of interleukin-8 (IL-8). In conclusion, our results imply that NK cells provide maturation signals and may play a role in inducing IL-8 production in DCs. Furthermore, the increased expression of CD86 on Malassezia-stimulated MDDCs might have a function in subsequent T-cell activation by DCs, and indicate a role for NK cell-DC interaction in modulating the immune responses to microbial stimuli.

Animals↗

PubMed2004

Evaluation of the nocebo effect during oral challenge in patients with adverse drug reactions.

The nocebo effect is the onset of untoward reactions following the administration of an indifferent substance. The oral challenge with alternative drugs plays a central role in the management of drug allergy and the use of inert substances is part of this procedure. We evaluated the occurrence and clinical characteristics of nocebo effect in patients with adverse drug reactions. Six hundred patients, seen in three different centres (Genoa, Naples and Verona) with a history of reactions to drugs, underwent a blind oral challenge with the administration of an indifferent substance and active drugs. The administration of an inert substance provoked untoward reactions in 54 patients (27%) in Verona, 60 (30%) in Naples and 48 (24%) in Genoa. The overall occurrence of nocebo effect was 27%. The majority of reactions were subjective symptoms (itching, malaise, headache etc), perceived as troublesome by all subjects. The occurrence was significantly higher in women than in men. Our data, collected in a large population, confirm that the nocebo effect occurs frequently in clinical practice. In managing adverse drug reactions through oral challenge the nocebo effect is mandatory to recognize false positive responses.

Adolescent↗

PubMed2004

Severe systemic allergic reaction induced by accidental skin contact with cow milk in a 16-year-old boy. A case report.

The symptoms of food allergy are rarely induced by skin contact. A 16-year-old boy was referred to our Allergology Centre after an episode of systemic symptoms triggered by accidental skin contact with a drop of cow milk (CM) dripped from a sandwich containing fresh cheese. The patient had been allergic to CM from the age of 24 months and had experienced several episodes of urticaria-angioedema after the ingestion of tiny or "hidden" amounts of CM proteins. In vivo and in vitro diagnostic procedures showed intense sensitisation to all CM proteins (1/100 dilutions of allergenic extracts produced large wheals, and class 4 specific IgE antibodies. Total IgE antibodies were elevate (770.0 UI/). A moderate degree of bronchial hyperresponsiveness was found (PC20 metacholine: 3.90 milligrams). This case report suggests that patients with a high degree of sensitisation to CM proteins should be alert to the danger of skin contact and should beware of "hidden" CM allergens.

Adolescent↗

PubMed2003

CCK-1 receptor blockade for treatment of biliary colic: a pilot study.

BACKGROUND: Loxiglumide is a potent and selective cholecystokinin-1 (CCK-1) receptor antagonist able to inhibit gall-bladder contraction. AIM: To assess the effect of CCK-1 receptor blockade on the pain of patients with biliary colic. PATIENTS AND METHODS: Fourteen patients with biliary colic but no suspicion for acute cholecystitis, were randomly and blindly assigned to loxiglumide (50 mg i.v.) or hyoscine-N-butyl bromide (20 mg i.v.) treatment. Pain intensity was monitored by a Visual Analogue Scale. Patients with less than 80% response at 30 min, were retreated with a second injection of the same compound. RESULTS: Reduction in pain score (mean +/- S.E.M.) was faster and significantly greater in patients treated with loxiglumide (n = 7) than in controls (n = 7): 88 +/- 7% vs. 47 +/- 12% after 20 min, P < 0.05; 92 +/- 6% vs. 49 +/- 13%, after 30 min, P < 0.05. Only one of seven patients treated with loxiglumide needed a second injection at 30 min (vs. six of seven controls, P < 0.05). No adverse effect was observed after either treatment. CONCLUSIONS: Loxiglumide is highly effective in obtaining pain relief in patients with biliary colic. The analgesic effect of CCK-1 receptor blockade is superior to that of a conventional anticholinergic treatment.

Adolescent↗

PubMed2003

Different phenotypes of colon carcinoma cells interacting with endothelial cells: role of E-selectin and ultrastructural data.

Adhesion molecules are intimately involved in the process of tumour progression. Among them, E-selectin is an inducible endothelial cell adhesion molecule that plays a role in the interactions of neoplastic cells with the endothelium. These interactions are required for the trans-endothelial migration of tumour cells that leads to the growth at the new sites. Since the detailed events in the early phase of metastasis still remain poorly defined, our study has undertaken an electron-microscopic analysis of the interactions of human colon carcinoma cells with endothelial cells as well as an analysis of the effect of recombinant purified E-selectin in the cell signalling involved in colon cancer cell malignant phenotype. Results revealed that SW480 and T84 colon cancer cell lines show different features, different adhesion kinetics, a different cytoskeletal organization, and a different tyrosine phosphorylation pattern when seeded on an endothelial cell monolayer or recombinant E-selectin. In particular T84 cancer cells adhere more efficiently to the E-selectin and this interaction is associated with pronounced morphological changes, actin redistribution and filopodial processes, and an increase in tyrosine phosphorylation of different proteins. These data support the hypothesis that E-selectin ligand is not only a cell-cell adhesion molecule but also initiates a signalling transduction pathway inside the cells.

Actins↗

PubMed2003

Role of calcium in E-selectin induced phenotype of T84 colon carcinoma cells.

The adhesion of cancer cells to the endothelium during the metastatic process involves the interaction of specific cell-cell adhesion receptors on the cell surface. E-selectin on endothelial cells and sialyl Lewis X carbohydrate component on tumor cells are mainly implicated in the adhesion of colon carcinoma cells to the endothelium of target organ. In this paper we show that binding of E-selectin to T84 colon tumor cells causes approximately a twofold increase in intracellular calcium concentration. In particular, using two inhibitors of receptor operated calcium channels, CAI and SK&F 96365, we present evidences that the augmentation in cytoplasmic calcium originates from ionic influx from extracellular sources. Furthermore, we demonstrated that modulation of [Ca2+]i by engagement of E-selectin receptor starts signal transduction pathways that affect cell spreading, tyrosine phosphorylation signaling, and cancer cell motility.

Antineoplastic Agents↗

PubMed2003

Development and validation of a bioanalytical method for the determination of the cholecystokinin type-1 (CCK(1)) receptor antagonist dexloxiglumide in human plasma.

A sensitive bioanalytical method for the measurement of dexloxiglumide, a new selective and potent cholecystokinin type-1 (CCK(1)) receptor antagonist, in plasma, is reported. The method is based on reversed-phase liquid chromatography with ultraviolet absorption detection. Samples are extracted under acidic conditions into an organic solvent, and following evaporation, reconstitution and centrifugation stages, the supernatant is injected on to an ODS column with detection at 244 nm. The method has been validated over the concentration range 0.2-20 microgram/ml, 0.2 microgram/ml being the lower limit of quantification. The overall precision and accuracy (expressed as relative error) of the method was less than 6.1 and 2.3%, respectively. Dexloxigulmide was shown to be stable in plasma when stored at -20 degrees C for at least 200 days. The method is suitable for studying the pharmacokinetics of dexloxiglumide in man.

Calibration↗

PubMed2003

General strategy for the management of bronchial asthma in pregnancy.

Epidemiological studies showed that bronchial asthma is one of the most common diseases which can complicate pregnancy (1-7%). In about 0.05-2% of the cases, asthma occurs as a life-threatening event. In the common medical practice a waiting strategy or, even, the complete refusal for drug therapies are frequently observed. This is justified by the fear of the possible adverse effects of drugs on developing fetus. On the contrary, several studies have demonstrated that severe and uncontrolled asthma may produce serious maternal and fetal complications, such as gestational hypertension and eclampsia, fetal hypoxemia and an increased risk of perinatal death. Therefore, all pregnant women suffering from bronchial asthma should be considered as potentially at high risk of complications and adequately treated. Since asthma is a chronic disease with acute exacerbations, a continuous treatment is mandatory to control symptoms, to prevent acute episodes and to reduce the degree of airway inflammation. The global strategy for asthma management in pregnancy includes five main topics: (1) objective evaluation of maternal/ fetal clinical conditions; (2) avoidance/control of triggering factors; (3) pharmacological treatment; (4) educational support; (5) psychological support. As far as drug therapy is concerned, the International Guidelines and Recommendations suggest that the general strategy does not differ significantly from management outside pregnancy. We herein review and discuss the available data and the criteria for the management of asthma in pregnant patients.

Adrenergic beta-Agonists↗

PubMed2003

Severe oral symptoms after the use of an oral solution containing ketoprofen in two NSAIDs-sensitive patients.

Cutaneous application of the nonsteroidal anti-inflammatory drug (NSAID) ketoprofen has been reported to induce contact dermatitis. However, there is no report of intraoral symptoms after the use of solutions containing this drug. In this report we describe two cases of severe intraoral symptoms after the use of a gargle containing ketoprofen in two patients with NSAIDs hypersensitivity. The patients underwent diagnostic procedures 6 months after the episodes of intraoral symptoms. Procedures included skin prick test for inhalant and food allergens, and total- and specific-IgE determinations to evaluate the presence of atopy. A single-blind, placebo-controlled challenge with different dilutions (1/1000, 1/100, 1/10, and 1/1) of ketoprofen oral solution was carried out by a modified version of a standardized protocol. We used the same commercial solution without the drug as placebo. Diagnostic procedures failed to demonstrate allergic sensitization to the common inhalant and food allergens. Both patients experienced a slight intraoral itching and edema of the lips a few minutes after the intraoral use of 1/100 dilution of active drug. Our cases suggest that the contact of an oral solution containing ketoprofen with oral mucosa may induce locally severe oral manifestations. Patients with NSAIDs sensitivity should be warned on the potential risk of using an oral solution containing this class of drugs.

Administration, Oral↗

PubMed2002

E-selectin modulates the malignant properties of T84 colon carcinoma cells.

The extravasation of metastatic cells is regulated by molecular events involving the initial adhesion of tumor cells to the endothelium and subsequently the migration of cells in the host connective tissue. E-selectin on endothelial cells and sialyl Lewis X carbohydrate component on tumor cells are mainly involved in the adhesion of colon carcinoma cells to the endothelium of target organ. Interaction of T84 colon cancer cells to purified E-selectin in vitro caused an increase in the tyrosine phosphorylation of a number of proteins as well as the modulation of cellular properties correlated to the metastatic phenotype. Specifically, E-selectin-stimulated actin reorganization, increased collagenase secretion, and induced cell migration. Treatment of T84 cells with herbimycin A inhibited cell adhesion as well as selectin-induced increase of cell migration, and cytoskeleton assembly. Our data demonstrate that binding of cancer cells to E-selectin starts signal transduction pathways which may affect the tumor metastatic abilities.

Benzoquinones↗