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M Martinelli

Publications and source records attributed to M Martinelli.

At least 19 recordsLinked to original sources
PubMed2000

High-field, multifrequency EPR spectroscopy using whispering gallery dielectric resonators.

High-field/high frequency EPR spectroscopy measurements are shown. Experiments were carried out at 240- and 316-GHz frequencies. The employed apparatus uses a novel combination of far infrared molecular lasers and of probehead exploiting dielectric resonators working in the whispering gallery modes. This approach constitutes a relatively simple method of multifrequency EPR spectroscopy and opens appealing perspectives in high-sensitivity EPR spectroscopy up to the THz regime.

Electron Spin Resonance Spectroscopy↗
PubMed2000

A program for the optimization of cyclosporine therapy using population kinetics modeling.

Cyclosporine is one of the most widely used immunosuppressive agents in organ transplantation. Due to large inter- and intra-individual variations, its behavior in the specific patient is still difficult to predict. Dosage optimization is thus mainly performed on a trial-and-error basis. In this paper, we present a new program based on the population kinetics approach, which was designed to help physicians in the difficult task of adjusting patient specific cyclosporine dosing regimens. Dose optimization is carried out by model simulation, using a two-compartment mathematical model of cyclosporine kinetics to predict the drug behavior in the patient. Two of the model parameters are assumed from the literature, the other two are estimated from the patient data through a Bayesian estimation procedure. Previous information needed by the Bayesian algorithm is derived by a population analysis, performed beforehand and based on a nonlinear mixed effect model. A user-friendly graphical interface written in Delphi under Windows makes the program easily accessible to physicians. A preliminary retrospective validation of the program, performed on data from 18 renal transplanted patients, yielded very satisfactory results.

Algorithms↗
PubMed2000

Genetics of nonsyndromic cleft lip and palate: a review of international studies and data regarding the Italian population.

The aims of this review are (1) to illustrate current knowledge of the mode of inheritance and the loci involved in the cleft lip and palate and (2) to summarize the results of our investigations, which were carried out in Italy. It is well established that nonsyndromic cleft of the lip with or without the palate (CL+/-P) and cleft palate only (CPO) are separate entities. Genetic heterogeneity has been observed in CL+/-P, which involves different chromosome regions, mainly 6p23 (OFC1), 2q13 (OFC2), and 19q13.2 (OFC3), as well as other loci, such as 4q25-4q31.3 and 17q21. Furthermore, an interaction between different genes has been suggested in the oligogenic model. In one case at least, an OFC1 and OFC2 interaction has been demonstrated. The mode of inheritance of CPO is compatible with a recessive single major gene model, while an association with a candidate gene, mapping on the chromosome region 2q13/TGFalpha, remains to be confirmed.

Animals↗
PubMed1999

Simultaneous micromechanical and electromagnetic detection of electron paramagnetic resonance

The peculiar advantages of simultaneous observation by electromagnetic and micromechanical methods in EPR spectroscopy are discussed. The development of a novel apparatus with the capability of this simultaneous detection is described. Experiments at 23 GHz show the performance of the apparatus. The problems related to the sensitivity and to the spatial resolution are analyzed. Future prospects are presented. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Combined segregation and linkage analysis of nonsyndromic orofacial cleft in two candidate regions.

We applied a complex segregation analysis to 46 pedigrees with a total of 121 nuclear families and 660 individuals, to verify hypotheses regarding the inheritance of OFC and linkage with markers on chromosomes 6 and 2. The POINTER program for segregation analysis strongly rejected the hypothesis of no familial transmission of OFC in these families. When the hypothesis of a two-locus model was tested with COMDS, the analysis showed the presence of at least two loci and the model assuming a dominant major gene and a recessive modifier locus was statistically accepted. Given the fitted two-locus model, we tested for a possible linkage between the major OFC locus and the two markers studied. For D6S259, the estimate of the recombination fraction was theta = 0.098, corresponding to a LOD score around 2.1. On the contrary, the data analysis concerning the D2S378 marker showed an estimate of the recombination fraction not significantly different from the independence hypothesis.

Chromosomes, Human, Pair 2↗
PubMed1999

[Syphilis in adolescent mothers in the city of Posadas, Province of Misiones].

During three months (April to June 1997) 1,238 consecutive pregnant women were studied at the time of delivery at the Madariaga public Hospital. Syphilis was confirmed in 26 (2.1%) women, and 15 cases (57.7%) of congenital syphilis were demonstrated in newborns one of whom was a stillborn. Of the syphilitic women 61.5% were 20 years old (average), 65.4% were single, 19.2% had a stable partner and 15.4% were married; 70% of them had finished elementary school (seven years), but despite this discrete level of instruction and that they were benefited with free health attention, 73% of them had not started or completed the pregnancy control. None of these women acted as sexual workers or were drug users; 57.7% were unemployed and the remainder worked as domestic servants or were still going to school. Menarca started at 13 (average) and the age of the first sexual activity was 15 (average). The distribution of the cases of syphilis within the city area shows four clusters that coincide with the lower income population, but not with marginal groups. The failure to submit to medical control during pregnancy among syphilitic women is directly linked with an increased risk for congenital syphilis. The specific prevalence of syphilis in women (20 years old or less) pregnant or not, shows an alarming hidden epidemic situation. An interinstitutional and communitary program, with direct interventions within the detected population clusters, is now underway in order to control syphilis. Undesired pregnancy and syphilis seem to be associated with adolescent unsafe sex conducts. A coordinated program between Public Health Service and National Misiones University is operating, visiting home by home, in order to decrease or eliminate congenital syphilis and is considered a priority health problem. Unfortunately, if sexual conducts do not undergo changes in the near future, at least by the correct use of condoms, HIV will replace syphilis.

Adolescent↗
PubMed1998

Suggestive linkage between markers on chromosome 19q13.2 and nonsyndromic orofacial cleft malformation.

Nonsyndromic cleft lip with or without cleft palate (OFC) is a common birth defect that has genetic bases. The nature of the genetic contribution is still to be clarified; however, some chromosome regions and candidate genes have been proposed for this malformation. We examined linkage between BCL3, a proto-oncogene located in 19q13.2, and OFC in a sample composed of 40 multiplex pedigrees using both nonparametric and parametric methods. The affected pedigree member statistics and the transmission disequilibrium test supported a role for BCL3 in causing OFC, while no evidence of linkage or genetic heterogeneity was found with the lod score method.

B-Cell Lymphoma 3 Protein↗
PubMed1998

A locus in 2p13-p14 (OFC2), in addition to that mapped in 6p23, is involved in nonsyndromic familial orofacial cleft malformation.

An allelic association between the transforming growth factor alpha gene (TGFA) situated in the chromosome 2p13 region and nonsyndromic cleft lip with or without cleft palate, also named orofacial cleft (OFC), was found in several population studies. However, no linkage between gene and malformation has shown up until now, probably due to the presence of genetic heterogeneity and the small sample size analyzed. Previously, we employed a collection of 38 OFC families to demonstrate linkage to the 6p23 chromosome region with the presence of genetic heterogeneity. In the present study we tested whether, in the same sample, linkage between OFC and markers on 2p13 could be determined. Evidence for genetic heterogeneity in our family set was apparent, by both pairwise and multipoint linkage analyses. Moreover, lod scores > 3 were found for marker D2S378 when families linked to the 6p23 markers were analyzed. Taken together these results indicate a role for the TGFA, or for another gene physically close to it, and suggest an interaction between two different genes, OFC1 and OFC2, mapped in 6p23 and 2p13, respectively, in the development of the cleft.

Chromosomes, Human, Pair 2↗
PubMed1998

Lack of linkage disequilibrium between transforming growth factor alpha Taq I polymorphism and cleft lip with or without cleft palate in families from Northeastern Italy.

Cleft lip with or without cleft palate (CL +/- P) is the most frequent craniofacial malformation in different human populations and its cause is largely unknown. Several studies based on population associations have suggested that an allele mapping in the transforming growth factor alpha locus could be responsible, as a risk factor, for the development of the defect. Our investigation of the Taq I polymorphism at the transforming growth factor alpha locus, performed in 40 CL +/- P families, did not find evidence for linkage disequilibrium with particular alleles. Moreover, tight linkage was excluded with the traditional LOD score method.

Alleles↗
PubMed1998

All mechanical low rectal anastomosis in children.

PURPOSE: The aim of this study is to demonstrate the feasibility and usefulness of mechanical suturing in children for low rectal anastomosis. METHODS: The study group includes 31 children operated on from January 1993 to July 1996 by the same senior surgeon, performing the modified Duhamel procedure for Hirschsprung's disease in 17 children, intestinal neuronal dysplasia in seven, and the Knight-Griffen procedure in seven pediatric patients with chronic ulcerative colitis. RESULTS: In all the cases the technique of "viscero-synthesis" was performed using the mechanical stapler. A circular stapler has been used for the end-to-end and the end-to-side anastomosis between the anal canal or the back wall of the rectum with the pulled viscus, while a linear endoscopic stapler (GIA) has been used for the consolidation of the rectocolic wall in the modified Duhamel technique. CONCLUSIONS: The results obtained demonstrate that the mechanical staplers in children are safe and effective in low rectal anastomosis, sparing operative time and reducing the risk of anastomotic dehiscence; however, the size of circular instruments limits its use in neonates and small infants.

Adolescent↗
PubMed1997

Evidence of linkage to 6p23 and genetic heterogeneity in nonsyndromic cleft lip with or without cleft palate.

Nonsyndromic cleft lip with or without cleft palate (CL+/-P) is a congenital orofacial anomaly that derives from an embryopathy with failure of nasal process and palatal shelves fusion. CL+/-P is one of the most common malformations, affecting 1/700-1/1000 live births among Caucasians. Early investigations have suggested that a clefting gene may be located on the short arm of chromosome 6 (6p), as well as in other regions. In this study, we analyzed a large sample of families by using eight PCR markers that map on chromosome region 6p23-p24. The admixture test, as implemented in the HOMOG program, was significant when tested against multipoint data (alpha = 0.60, P value 0.00004); the lod score calculated, assuming heterogeneity, was 3.60 at 1 cM telomeric to D6S259. Taken together these data demonstrate the presence of a locus for CL+/-P in the 6p23 chromosome region.

Chromosomes, Human, Pair 6↗
PubMed1997

Familial transmission of a serious disease--producing group A streptococcus clone: case reports and review.

Invasive group A streptococcus (GAS) infections are emerging diseases; however, person-to-person transmission of invasive GAS producing life-threatening infection has been observed rarely. We report a small intrafamilial cluster of life-threatening GAS infections. A previously healthy 47-year-old father developed necrotizing fasciitis of the neck. Two days later, his 16-year-old daughter developed streptococcal angina, pneumonia, and pleural empyema. Both patients had signs of streptococcal toxic shock syndrome. Pulsed field gel electrophoresis revealed that the M6 strains of GAS isolated from the father and daughter had identical patterns. Cases of person-to-person transmission of invasive GAS infection reported in the literature are also reviewed.

Adolescent↗
PubMed1996

Dietary fish oil normalize dyslipidemia and glucose intolerance with unchanged insulin levels in rats fed a high sucrose diet.

The aim of this study was to investigate the relationship between the lipid-lowering effects of fish oils and concomitant consequences on glucose tolerance and insulin sensitivity in an experimental animal model of hypertriglyceridemia induced by high sucrose intake. To achieve this goal, male Wistar rats were fed a semi-synthetic sucrose rich diet (SRD) (w/w: 62.3% sucrose, 8% corn oil, 17% protein) for 90 days. At the time, a well established and permanent hypertriglyceridemia accompanied by glucose intolerance was present. After that, one half of the animals continued on the SRD up to 120 days. The other half received an SRD in which the source of fat was substituted by cod liver oil (w/w 7% CLO plus 1% corn oil) from day 90 to 120 (SRD+CLO). Control rats were fed a semi-synthetic diet (CD) (w/w: 62.5% corn starch, 8% corn oil, 17% protein) throughout the 120 days experimental period. Results obtained after the experimental period show that the hypertriglyceridemia and glucose intolerance ensuing long term feeding normal rats with a sucrose-rich diet could be completely reversed mediating no change in circulating insulin levels by shifting the source of fat in the diet from corn oil to cod liver oil. These findings suggest that manipulation of dietary fats may play a role in the management of the lipid disorders associated with glucose intolerance and insulin resistance.

Animals↗
PubMed1996

Recombinant human secretory phospholipase A2 released thromboxane from guinea pig bronchoalveolar lavage cells: in vitro and ex vivo evaluation of a novel secretory phospholipase A2 inhibitor.

The primary objective of this study was to develop a functional assay that could provide rapid and reliable information on some pharmacologic characteristics of a novel inhibitor of human secretory phospholipase A2 (sPLA2). Guinea pig bronchoalveolar lavage (BAL) fluid, containing predominantly macrophages, eosinophils and epithelial cells, released thromboxane A2, as measured by thromboxane B2, in a concentration-dependent manner on exposure to recombinant human sPLA2 (rh-sPLA2). Similarly, n-formyl-L-methionyl-L-leucyl-L-phenylalanine (n-F-Met-Leu-Phe) or arachidonic acid also released this lipid mediator. Indomethacin, a cyclooxygenase inhibitor, blocked synthesis of thromboxane in response to these agents. p-Bromophenacylbromide-inactivated rh-sPLA2 was substantially less effective than the untreated enzyme in causing release of thromboxane. LY311727 is a potent indole-derived inhibitor of the isolated enzyme (IC50 = 23 nM). Incubation of this agent with BAL cells, just before addition of rh-sPLA2, reduced release of thromboxane with an IC50 = 1.8 x 10(-6) M. Specificity for sPLA2 was demonstrated in that LY311727, unlike indomethacin, did not reduce synthesis and subsequent release of thromboxane A2 in response to arachidonic acid. Using this technique as a basis, we determined whether LY311727 could sufficiently accumulate in lung after i.v. administration to inhibit rh-sPLA2-induced thromboxane A2 release from BAL cells. The compound, given i.v. to guinea pigs 5 min before collecting BAL fluid, produced a dose-dependent inhibition of rh-sPLA2 with an ED50 = 50 mg/kg. Thus, new in vitro and ex vivo assays were developed that permit functional evaluation of novel sPLA2 inhibitors. These techniques should serve as secondary assays for evaluation of human sPLA2 inhibitory activity from a chemical series and in addition provide initial data related to metabolic stability and distribution to the lung.

Animals↗
PubMed1994

Influences of dimethindene maleate in a new formulation on oculo and psychomotor performance using the oculodynamic test (ODT) in volunteers.

Most antihistamines are assumed to possess a more or less pronounced sedative potential in addition to their antihistaminic properties. Therefore, a single-blind three-way crossover study was designed to assess the influence of single-dose dimethindene maleate (new "once a day formulation") on vigilance and performance vs. loratadine as reference and vs. placebo. Drug effects on performance were tested in 18 healthy volunteers by the oculodynamic test [ODT, i.e. choice reaction task (CRT), combined with recording of electrooculography (EOG) and cardiovascular parameters] and effects on subjective well-being by visual analogue scales (VAS). Main target parameters for evaluation of CNS-effects are latency and subjective perception of sedation (VAS). Neither statistically significant nor clinically relevant differences in all objective and subjective target variables (ODT and VAS) between active drugs and placebo, after single-dose administration were found. The same holds for accessory EOG, CRT and vital parameters under workload.

Adult↗