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M Maresca

Publications and source records attributed to M Maresca.

At least 19 recordsLinked to original sources
PubMed2006

Accurate prediction of autologous stem cell apheresis yields using a double variable-dependent method assures systematic efficiency control of continuous flow collection procedures.

BACKGROUND AND OBJECTIVES: Stem cell collection is a standard procedure for the procurement of autologous grafts to rescue myelosuppression induced by high-dose treatments. Accurate prediction of collection yields may contribute to optimize planning and quality control of collection. MATERIALS AND METHODS: Data of 313 autologous haematopoietic stem cell (AHSC) evaluable collections performed in 208 patients with haematologic and non-haematologic neoplasms from seven centres were prospectively analysed to test the accuracy of yield predictions generated by a formula that required the input of peripheral blood (PB) CD34+ cell precount and desired PB volume to be processed. Data were matched in a standard linear regression, in a zero-point regression analysis and tested for prediction accuracy. Further 165 AHSC collections were analysed on a single-centre basis, using yield predictions as reference standards. RESULTS: Analysis showed high levels of correlation between measured collection yields (my) and predictions (py) (R = 0.85; P = 0.000000) as well as high degree of prediction accuracy (my vs. py at paired t-test: P = 0.114781; median my/py ratio = 1.23). Analysis of additional 165 AHSC collections on a single-centre basis showed that the analysed centres had 70% or more measured yields comprising the 0.6-1.8 interval of the my/py ratio. The observance of the 'efficiency' my/py interval assured collection quality control in these centres confirming the reliability of the method. CONCLUSIONS: This prediction method generates accurate and immediate yield predictions allowing collection planning and rapid efficiency control. As a consequence of our study, four centres out of seven use the described method to plan both leukapheresis number and single-procedure blood processing volume while the remaining three centres plan leukapheresis number on the basis of our predictions, maintaining a fixed single-procedure 200 ml/kg blood volume processing, according to their centre AHSC collection policy.

Adolescent↗
PubMed2003

A comparison of ultrasonography and magnetic resonance imaging in the evaluation of temporomandibular joint involvement in rheumatoid arthritis and psoriatic arthritis.

OBJECTIVE: To define the diagnostic value of ultrasonographic (US) examination in comparison with magnetic resonance imaging (MRI) for the assessment of temporomandibular joint (TMJ) involvement in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). METHODS: MRI and US examinations were performed in 33 patients (22 with RA and 11 with PsA). Alterations of the disc, alterations of the condyle and joint effusion were evaluated. RESULTS: Pathological changes of the TMJ were observed by MRI in 24 patients and by US in 31 patients. The sensitivity and specificity of US were calculated in comparison with MRI. The sensitivity was 72.2% and the specificity was 60% in the assessment of pathological changes of the TMJ. The sensitivity was 69.6% with specificity of 30.0% in the assessment of alterations of the disc; the sensitivity was 70.6% with specificity of 75.0% in the assessment of joint effusion. Significant concordance was not observed in the assessment of condylar alterations. CONCLUSIONS: US imaging appears able to detect different pathological changes of the TMJ and may be considered an important diagnostic tool for clinical evaluation of the TMJ in RA and PsA.

Adult↗
PubMed2002

Role of the thyroid-stimulating hormone receptor signaling in development and differentiation of the thyroid gland.

The thyroid-stimulating hormone/thyrotropin (TSH) is the most relevant hormone in the control of thyroid gland physiology in adulthood. TSH effects on the thyroid gland are mediated by the interaction with a specific TSH receptor (TSHR). We studied the role of TSHTSHR signaling on gland morphogenesis and differentiation in the mouse embryo using mouse lines deprived either of TSH (pit(dw)pit(dw)) or of a functional TSHR (tshr(hyt)tshr(hyt) and TSHR-knockout lines). The results reported here show that in the absence of either TSH or a functional TSHR, the thyroid gland develops to a normal size, whereas the expression of thyroperoxidase and the sodium/iodide symporter are reduced greatly. Conversely, no relevant changes are detected in the amounts of thyroglobulin and the thyroid-enriched transcription factors TTF-1, TTF-2, and Pax8. These data suggest that the major role of the TSH/TSHR pathway is in controlling genes involved in iodide metabolism such as sodium/iodide symporter and thyroperoxidase. Furthermore, our data indicate that in embryonic life TSH does not play an equivalent role in controlling gland growth as in the adult thyroid.

Animals↗
PubMed2001

The mycotoxin ochratoxin A alters intestinal barrier and absorption functions but has no effect on chloride secretion.

Ochratoxin A (OTA) is a mycotoxin that contaminates cereals and animal feed and causes nephropathy to a variety of animal species. OTA is also known as a potent immunotoxic, teratogenic, and carcinogenic mycotoxin. In addition, OTA ingestion induces intestinal injuries, including inflammation and diarrhea. With the aim to study the cellular mechanisms associated with the intestinal toxicity of OTA, two human epithelial intestinal cell lines (HT-29-D4 and Caco-2-14 cells), widely used as in vitro models for the intestinal epithelium, were incubated with OTA. The main effects of the mycotoxin were an inhibition of cellular growth and a dramatic decrease of transepithelial resistance in both cell lines. Since transepithelial resistance reflects the organization of tight junctions over the cell monolayer, these data may suggest that OTA could potentiate its own absorption through paracellular pathways. OTA induced a 60% decrease of sodium-dependent glucose absorption but increased the absorption of fructose and L-serine in HT-29-D4 cells. Moreover, the mycotoxin did not inhibit the cAMP-dependent chloride secretion through the cystic fibrosis transmembrane conductance regulator channel. The inhibitory effect of OTA on active glucose transport was partially antagonized by L-phenylalanine, but not by alpha-tocopherol, suggesting that the toxicity of OTA could result from an inhibition of protein synthesis, rather than an induction of lipid peroxidation. In particular, OTA affected the protein content of plasma membrane microdomains, which are known to regulate tight junction assembly and intestinal transport activity. Taken together, these data showed that OTA alters both barrier and absorption functions of the intestinal epithelium.

Caco-2 Cells↗
PubMed1999

Human erythrocyte glycosphingolipids as alternative cofactors for human immunodeficiency virus type 1 (HIV-1) entry: evidence for CD4-induced interactions between HIV-1 gp120 and reconstituted membrane microdomains of glycosphingolipids (Gb3 and GM3).

Glycosphingolipids from human erythrocytes mediate CD4-dependent fusion with cells expressing human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins. To identify the glycosphingolipid(s) which participates in the fusion process, we have analyzed the interaction of HIV-1 gp120 (X4 and R5X4 isolates) with reconstituted membrane microdomains of human erythrocyte glycosphingolipids. We identified globotriaosylceramide (Gb3) and ganglioside GM3 as the main glycosphingolipids recognized by gp120. In the presence of CD4, Gb3 interacted preferentially with the X4 gp120, whereas GM3 interacted exclusively with the R5X4 gp120. These data suggest that glycosphingolipid microdomains are required in CD4-dependent fusion and that Gb3 and/or GM3 may function as alternative entry cofactors for selected HIV-1 isolates.

CD4 Antigens↗
PubMed1997

Substance P in the serum of patients with rheumatoid arthritis.

Serum substance P was assayed in rheumatoid arthritis patients and healthy controls to evaluate whether neurogenic inflammation with substance P release is significant in rheumatoid arthritis. A very sensitive competitive immunoenzymetric assay was used. Mean serum substance P level was significantly higher in rheumatoid arthritis patients than in controls and was not correlated with disease duration, morning stiffness duration, Thompson's articular index, Larsen's radiographic score, or the following laboratory indices of inflammation: erythrocyte sedimentation rate, C-reactive protein, and alpha 1-acid glycoprotein. Neurogenic inflammation with substance P release may contribute significantly to the pathogenesis of rheumatoid arthritis. The absence of correlations between serum substance P and clinical or laboratory indices of inflammation may reflect complex interactions between neurogenic inflammation and other pathogenic mechanisms, which may influence clinical features and laboratory tests in rheumatoid arthritis patients.

Adult↗
PubMed1997

Surgical laparoscopy with intraoperative manometry in the treatment of esophageal achalasia.

The aim of this study was to describe and evaluate the laparoscopic treatment of esophageal achalasia in nine patients over a 35-month period. Five trocars were used to perform a Heller's myotomy to completely eliminate the cardial high-pressure zone, under manometric control. Intraoperative manometry also was used to calibrate a pick degrees 360 Rossetti's antireflux wrap. A complete regression of symptoms was observed postoperatively in seven of nine patients (77.8%); in two patients (22.2%) a moderate dysphagia persisted, but it disappeared 3 and 6 months, respectively. Only one intraoperative complication (esophageal perforation, recognized and laparoscopically repaired) occurred. At the present follow-up of 18 +/- 5.34 months (range 6-35), no dysphagia or symptoms related to reflux have been observed. Laparoscopic treatment of esophageal achalasia is considered a safe and effective procedure, and the results of this procedure are comparable with those of the open technique. Advantages common to other laparoscopic techniques are emphasized.

Adolescent↗
PubMed1996

Itch and pain.

Explore the source record for details and available documents.

Antipruritics↗
PubMed1993

Osteopontin-hydroxyapatite interactions in vitro: inhibition of hydroxyapatite formation and growth in a gelatin-gel.

Osteopontin is a phosphorylated bone matrix sialoprotein, postulated to play a regulatory role in biomineralization. The effects of a crude preparation of rat bone osteopontin and a more highly purified bovine bone osteopontin were evaluated using a gel diffusion system to measure effects of 0.1-100 micrograms/ml of this matrix protein on hydroxyapatite formation and crystal proliferation. Bovine osteopontin at concentrations greater than 25 micrograms/ml inhibited both hydroxyapatite formation and growth in a dose-dependent manner. Osteopontin at concentrations lower than 25 micrograms/ml had no detectable effect on the amount of mineral accumulated in experiments with and without pre-formed hydroxyapatite seed crystals either when initial mineral deposition was assessed at 3.5 days, or when mineral formation and growth were assessed at 5 days. There was a statistically significant dose-dependent decrease in crystal length at all concentrations tested. The rat osteopontin preparation had similar inhibitory abilities. Partial dephosphorylation of bovine osteopontin with alkaline phosphatase removed its inhibitory ability, and reduced its ability to bind calcium. The affinity of bovine osteopontin for hydroxyapatite was determined based on a Langmuir adsorption isotherm, with values of K (binding affinity) and N (number of binding sites) being 0.026 ml/microgram and 1084 micrograms/m2, respectively. The data suggest that, in this system, osteopontin is an effective inhibitor of hydroxyapatite formation and growth due to its affinity for the hydroxyapatite crystals. In this system, osteopontin, distinct from other phosphoproteins which both promote and inhibit hydroxyapatite deposition, did not enhance mineral formation at any concentration tested.

Animals↗
PubMed1993

p-Bromophenacyl bromide potentiates hydrogen peroxide formation in human platelets challenged by thrombin and inhibits aggregation.

p-Bromophenacyl bromide, a potent alkylating agent inhibitor of phospholipase A2 and adenylate cyclase, potentiates hydrogen peroxide production in human platelets activated with thrombin. The maximal cooperative effect, specific for thrombin as inducer and potentiated by exogenous calcium, was observed at 2 microM BPB. Since it was shown that BPB is also a strong inhibitor of platelet aggregation (IC 50 = 3 +/- 1 microM) it is likely to suppose that the abnormal accumulation of hydrogen peroxide can influence platelet function.

Acetophenones↗
PubMed1992

Generation of hydrogen peroxide in resting and activated platelets.

The production of hydrogen peroxide was measured by following the oxidation of dichlorofluorescein (DCFH) entrapped into platelets. Resting platelets produced nanomolar quantities of DCF, which was proportional to the concentration of platelets and was steady during 1 h of incubation. A significant increase of basal DCF fluorescence was induced by stimuli namely thrombin, arachidonic acid, the Ca2+ ionophore A23187 and PMA. The effect of agonists has been also measured in the presence of 3-amino-1,2,4-triazole (AT) or N-ethylmaleimide (NEM), inhibitors of catalase and glutathione peroxidase, respectively. A further significant enhancement of DCF produced in stimulated platelets was detected only in the presence of NEM. A correlation was found between the increase in DCF and externally added hydrogen peroxide or the oxidizing species formed by xanthine oxidase plus acetaldehyde. The yield was not affected by superoxide dismutase and was higher in the presence of AT or NEM. A cooperative effect in the presence of both inhibitors was shown. Glutathione peroxidase plus glutathione diminished the level of DCF to basal levels.

Blood Platelets↗
PubMed1992

Treatment of proteoglycan aggregates with physeal enzymes reduces their ability to inhibit hydroxyapatite proliferation in a gelatin gel.

In vitro, cartilage proteoglycans (PGs) are effective inhibitors of hydroxyapatite formation and growth. Their inhibitory ability decreases with decreasing PG size and charge density. It has been suggested that the enzyme-mediated alteration in the size and conformation of PGs in the growth plate may similarly facilitate the calcification process. In this study, a gelatin gel system was used to monitor hydroxyapatite formation and growth in the presence of proteoglycan aggregates, before and after enzyme treatment. To reproduce the physeal degradation cascade, an enzyme preparation was used that contained all of the growth plate enzymes. At a concentration of 500 micrograms/ml, the untreated proteoglycan aggregates reduced the amount of mineral formed by 30%. When the aggregates were treated with the heat-inactivated enzyme, the same extent of inhibition was found. In contrast, treating the aggregates with the crude growth plate enzyme preparation removed all the inhibitory ability, such that 500 micrograms/ml of proteoglycan preparation yielded 10% more mineral than the controls. Treatment of the aggregates with chondroitinase ABC and trypsin, similarly removed all the inhibitory ability. These data, suggest that enzymatic degradation of proteoglycans may contribute to the regulation of growth plate calcification.

Animals↗
PubMed1992

Increased hydrogen peroxide formation in platelets of patients affected with essential thrombocythaemia (ET).

The basal platelet level of reactive oxygen species and their enhancement following stimulation by different agonists were determined in a selected group of patients with essential thrombocythaemia (ET). Activated platelets had lower levels of superoxide anion and higher intracellular concentrations of hydrogen peroxide than controls. Higher levels of lipid peroxidation induced by N-ethylmaleimide were also observed. Measurement of the most important enzymes generating and scavenging these reactive oxygen species revealed increased specific activities of NADPH-cytochrome c reductase and superoxide dismutase and a decrease in platelet catalase activity in patients with ET. Since an abnormal production of oxygen radicals seems to be implicated in various pathological conditions and aging processes, the increased amount of hydrogen peroxide found in platelets of patients could be involved in some of the platelet alterations described in ET.

Blood Platelets↗
PubMed1992

The concept of pain in the 17th century.

The 17th century is very important in the history of sensation and pain. Philosophers, as Descartes, Hobbes, Spinoza, defined a new philosophy of science. Physicians of the iatro-chemical school introduced the first principles of biochemistry, tied to the sensations. Physicians of the iatro-mechanical school postulated a really modern concept: the importance of nerve juices in sensibility and pain.

Europe↗
PubMed1992

1,5-Benzodiazepines. X. Dialkylamino substituted 1,5-benzodiazepine and [1,2,4]triazolo [4,3-a][1,5] benzodiazepine derivatives with inhibitory activity on PAF-induced platelet aggregation.

Novel 4-(dialkylamino) substituted (4, 5 c, 8) and 2,4-bis(dialkylamino) substituted (6) 1,5-benzodiazepine derivatives were synthesized. Both these new compounds and the substituted 4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepine-5-amines 2 a-h, recently described by us, were tested in vitro for their inhibitory activity on the PAF-induced aggregation of human platelets. Actually, bicyclic compounds 4 d, 5 c and tricyclic compounds 2 g, h showed a significant activity: in all them the dialkylamino substituent was the 4-(ethoxycarbonyl)-1-piperazinyl group. On the contrary, compounds 4 d, 5 c, 2 g,h showed practically no inhibitory activity when platelet aggregation was induced by ADP, A23187, or collagen.

Benzodiazepines↗
PubMed1991

Mode of action of 2-(diethylamino)-7-ethoxychromone on human platelets.

The in vitro effect of 2-(diethylamino)-7-ethoxychromone (RC39XVIII) on human platelet aggregation induced by several agonists and on thromboxane B2 formation, granule release and intracellular cAMP elevation has been studied. The chromosome-derivative exerts a dose-dependent inhibitory effect on aggregation produced by U46619, arachidonic acid, thrombin, collagen and ADP. RC39XVIII inhibits aggregation, TxB2 formation and granule release in parallel. Moreover the drug potentiates cAMP accumulation induced by iloprost and forskolin. The drug also inhibits soluble cAMP phosphodiesterase in a dose-dependent manner. No effect on adenylate cyclase activity measured in platelet membranes was evident.

Adenosine Diphosphate↗