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Biomedical subjects

A Romano

Publications and source records attributed to A Romano.

At least 19 recordsLinked to original sources
PubMed2001

Branching fraction and photon energy spectrum for b --> s gamma.

We have measured the branching fraction and photon energy spectrum for the radiative penguin process b-->s gamma. We find Beta(b-->s gamma) = (3.21+/-0.43+/-0.27(+0.18)(-0.10))x10(-4), where the errors are statistical, systematic, and from theory corrections. We obtain first and second moments of the photon energy spectrum above 2.0 GeV, = 2.346+/-0.032+/-0.011 GeV, and - (2) = 0.0226+/-0.0066+/-0.0020 GeV(2), where the errors are statistical and systematic. From the first moment, we obtain (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) the heavy quark effective theory parameter Lambda = 0.35+/-0.08+/-0.10 GeV.

Journal Article↗
PubMed2001

Hadronic mass moments in inclusive semileptonic B meson decays.

We have measured the first and second moments of the hadronic mass-squared distribution in B-->X(c)l nu, for P(lepton)>1.5 GeV/c. We find = 0.251+/-0.066 GeV(2), <(M(2)(X)- )(2)> = 0.576+/-0.170 GeV(4), where M macro(D) is the spin-averaged D meson mass. From that first moment and the first moment of the photon energy spectrum in b-->s gamma, we find the heavy quark effective theory parameter lambda(1) (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) to be -0.24+/-0.11 GeV(2). Using these first moments and the B semileptonic width, and assuming parton-hadron duality, we obtain absolute value of V(cb) = 0.0404+/-0.0013.

Journal Article↗
PubMed2001

Comparison of effects of ioxaglate versus iomeprol on histamine and tryptase release in patients with ischemic cardiomyopathy.

We observed a release of histamine, but not of tryptase, in arterial blood from 64 patients with ischemic heart disease and 24 patients without coronary disease, which was provoked by ioxaglate, a ionic compound, but was not provoked by iomeprol, a non-ionic radiocontrast compound. The release of histamine in arterial blood after ionic contrast medium injection was higher in patients with ischemic heart disease compared with patients without coronary disease, suggesting that an increased release from heart mast cells previously observed exists also for systemic blood basophils.

Basophils↗
PubMed2001

Allele varepsilon4 of apolipoprotein E gene is less frequent in Down syndrome patient of the Sicilian population and has no influence on the grade of mental retardation.

We evaluated the allele (and genotype frequencies in 60 Down syndrome (DS), 25 mothers and 57 controls from Sicily and its relation with mental retardation. DS patients and sex ratio (M:F) was 22.1+/-10.5 and 1.14, respectively. Allele varepsilon4 and varepsilon3 frequencies were respectively lower (P=0.015) and higher (P=0.005) in DS patients compared to controls. Genotype varepsilon3/varepsilon4 and varepsilon3/varepsilon3 were less (P=0.03) and more frequent (P=0.001) in DS patients, with respective odd ratios of 0.31 (CI at 95%: 0.18-0.49) and of 4.4 (CI at 95%: 3.4-5.7). No difference of allele (distribution was found in function of the grades of mental retardation according to DMS-IV. Our results show that the implication of Apo-E4 in the pathogenesis of Alzheimer disease cannot be extrapolated in that of dementia of DS.

Adolescent↗
PubMed2001

Bounds on the CP asymmetry in b --> sgamma decays.

We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.

Journal Article↗
PubMed2001

Bounds on the CP asymmetry in like-sign dileptons from B(0)B*(0) meson decays.

We have measured the charge asymmetry in like-sign dilepton yields from B(0)B*(0) meson decays using the CLEO detector at the Cornell Electron Storage Ring. We find a(0)(ll) identical with[N(l(+)l(+))-N(l(-)l(-))]/[N(l(+)l(+))+N(l(-)l(-))] = +0.013+/-0.050+/-0.005. We combine this result with a previous, independent measurement and obtain Re(epsilon(B))/(1+ the absolute value of epsilon(B)(2)) = +0.0035+/-0.0103+/-0.0015 (uncertainties are statistical and systematic, respectively) for the CP impurity parameter, epsilon(B).

Journal Article↗
PubMed2001

Observation of new states decaying into Lambda+(c)pi(-)pi(+).

Using 13.7 fb(-1) of data recorded by the CLEO detector at the Cornell Electron Storage Ring, we investigate the spectrum of charmed baryons which decay into Lambda+(c)pi(-)pi(+) and are more massive than the Lambda+(c)(2625) baryon. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda+(c) baryon; the other is narrow with an invariant mass of 596+/-1+/-2 MeV above the Lambda+(c) mass.

Journal Article↗
PubMed2001

Evidence of New States Decaying into Xi(*)(c)pi.

Using 13.7 fb(-1) of data recorded by the CLEO detector at Cornell Electron Storage Ring, we report evidence of two new charmed baryons: one decaying into Xi(0')(c)pi(+) with the subsequent decay Xi(0')(c)-->Xi(0)(c)gamma, and its isospin partner decaying into Xi(+')(c)pi(-) followed by Xi(+')(c)-->Xi(+)(c)gamma. We measure the following mass differences for the two states: M(Xi(0)(c)gammapi(+))-M(Xi(0)(c)) = 318.2+/-1.3+/-2.9 MeV and M(Xi(+)(c)gammapi(-))-M(Xi(+)(c)) = 324.0+/-1.3+/-3.0 MeV. We interpret these new states as the J(P) = 1 / 2(-) Xi(c1) particles, the charmed-strange analogs of the Lambda(+)(c1)(2593).

Journal Article↗
PubMed2001

Observation of B --> phiK and B --> phiK*.

We have studied two-body charmless hadronic decays of B mesons into the final states straight phiK and phiK(*). Using 9.7 million B&Bmacr; pairs collected with the CLEO II detector, we observe the decays B- --> phiK- and B0--> phiK(*0) with the following branching fractions: B(B--->phiK-) = (5.5(+2.1)(-1.8)+/-0.6)x10(-6) and B(B0--> phiK(*0)) = (11.5(+4.5+1.8)(-3.7-1.7))x10(-6). We also see evidence for the decays B0-->phiK0 and B---> phiK(*-). However, since the statistical significance is not overwhelming for these modes, we determine upper limits of <12.3x10(-6) and <22.5x10(-6) ( 90% confidence level), respectively.

Journal Article↗
PubMed2001

Observation of the Omega(0)(c) Charmed Baryon at CLEO.

The CLEO experiment at the CESR collider has used 13.7 fb(-1) of data to search for the production of the Omega(0)(c) (css ground state) in e(+)e(-) collisions at square root of (s) approximately 10.6 GeV. The modes used to study the Omega(0)(c) are Omega(-)pi(+), Omega(-)pi(+)pi(0), Xi-K-pi(+)pi(+), Xi0K-pi(+), and Omega(-)pi(+)pi(+)pi(-). We observe a signal of 40.4+/-9.0(stat) events at a mass of 2694.6+/-2.6(stat)+/-1.9(syst) MeV/c(2), for all modes combined.

Journal Article↗
PubMed2001

Prevalence of sensitization to Cupressus sempervirens: a 4-year retrospective study.

In the last few years Cupressus sempervirens has been identified as the cause of an increasing number of cases of late winter-early spring pollinosis in Mediterranean countries. We conducted a 4-year retrospective study of a large group of subjects with documented allergic respiratory disease in order to determine the prevalence, clinical significance and annual rate of sensitization to C. sempervirens pollen. Anamnestic data and skin prick tests (SPT) with common aeroallergens and C. sempervirens extract were collected from 1397 subjects (712 male and 685 female) resident in Latium, a region in central Italy, with complaints related to upper- or lower-respiratory-tract disorders or conjunctival disease. Two hundred and forty-three subjects (17.4%) showed positive results to C. sempervirens extract: 47 (19.3%) of them were monosensitized. The annual sensitization rate of SPT positivity to C. sempervirens varied from 7.2% in 1995 to 22% in 1998. All the subjects monosensitized to cypress pollen had symptoms from January through April. Our study suggests that sensitivity to C. sempervirens is responsible for respiratory symptoms in an increasing percentage of subjects. Further studies are needed to determine its frequency at the national level.

Adolescent↗
PubMed2001

Effect of natural allergen exposure on non-specific bronchial reactivity in asthmatic farmers.

The aim of the study was to assess the seasonal variability of non-specific bronchial reactivity (NSBR) evaluated with methacholine in asthmatic farmers allergic to pollens. Twenty farmers (16 male and four female) with allergy to pollens, e.g. 'Graminae' and 'Parietaria', entered the study. None of the patients had been previously treated with specific immunotherapy. Patients underwent a methacholine challenge at the first visit and then in the subsequent seasons. Four groups of tests were obtained according to the period when the challenge was performed. Group 1: challenges performed in December, January and February; group 2 in March, April and May; group 3 in June, July and August; group 4 in September, October and November. PD20 values were expressed as the natural logarithm of the cumulative dose of methacholine causing at least a 20% fall in FEV1. Bronchial hyperreactivity was highest in summer, followed by spring and autumn; in winter it was much lower. Multiple group analysis (ANOVA) showed statistically significant differences between the groups (P < 0.01). When the groups were compared individually, statistically significant differences existed only between group 1 (winter) and each of the other groups, respectively 2 (spring) (P = 0.02), 3 (summer) (P = 0.004) and 4 (autumn) (P = 0.02). The results underlined the importance of allergic inflammation in determining changes in NSBR. In the region where the study was carried out (central Italy), the grass and Paretaria pollination lasts from March to November. Therefore, farmers had a progressive increase in NSBR from spring to summer and a decrease in fall as a consequence of the varying pollen concentration in different seasons. The level of allergen exposure is, in fact, the main factor that determines the severity of bronchial inflammation, thus affecting NSBR.

Agriculture↗
PubMed2001

Expanding the boundaries of the transsphenoidal approach: a microanatomic study.

The anatomic features of a transsphenoidal approach are reviewed, focusing on the microsurgical anatomy of parasellar structures. Pertinent microsurgical anatomy is described in sufficient detail for the neurosurgeon to successfully extend a standard transsphenoidal approach for treatment of lesions involving the region of the tuberculum sellae, planum sphenoidale, supradiaphragmatic intradural space, and medial cavernous sinus. The parasellar region of 50 formalin-fixed cadaveric heads was examined by using magnification 3x to 40x. The arterial and venous systems of five cadaveric specimens were injected under pressure with colored silicone rubber. The sellar region of three specimens was examined histologically. Important anatomic landmarks identified in the roof of the sphenoid sinus include a carotid and trigeminal prominence, as well as a tubercular, clival, and opticocarotid recess. The diaphragma sella is actually comprised of two layers of dura, with a venous system (circular sinus) interposed between the layers. The dura mater of the pituitary gland separates the gland from the medial compartment of the cavernous sinus. The microanatomic detail necessary to extend the transsphenoidal approach to the supradiaphragmatic intradural space and medial compartment of the cavernous sinus is described. These data are presented to facilitate the clinical application of these extended approaches.

Cadaver↗
PubMed2001

Characterisation of cAMP-dependent protein kinase isoforms in the brain of the crab Chasmagnathus.

In the crab Chasmagnathus learning model, systemic administration of cAMP analogues that are specific activators or inhibitors of cAMP-dependent protein kinase (PKA) proved to respectively facilitate or impair long-term retention. The aims of the present work were to analyse PKA activity distribution in the crab brain and to characterise PKA isoforms. The neuropils from the eyestalk showed higher levels of induced PKA activity when compared with other neuropils of the central nervous system. Two PKA isoforms, homologous to mammalian PKA I and PKA II, were detected from central brain protein extracts using DEAE chromatography. Only PKA II was found in lateral protocerebrum extracts, suggesting a role of this isoform in the processing of visual inputs and in the integration of this information with other sensory inputs. PKA I was observed to be ten-fold more sensitive to cAMP than PKA II. cGMP induced a high activation of both PKA isoforms, similar to that obtained with cAMP. PKA I showed a two-fold greater sensitivity for cGMP than PKA II. An autophosphorylation assay was performed and a protein of 55 kDa, corresponding to phosphorylated R II regulatory subunit, was detected. The presence of a PKA I isoform with high sensitivity for cAMP in the central brain suggests a role of this subtype in long-term memory.

Animals↗
PubMed2001

Mechanical transmission of poleroviruses.

Previously, transmission of poleroviruses has relied solely on the use of their aphid vectors. Biolistic inoculation allowed for the first time the mechanical transmission of Beet western yellows virus (BWYV) and Potato leafroll virus (PLRV) to several host plants. Inoculation with purified preparations and viral RNA extracts of PLRV resulted in 30-50% systemically infected Nicotiana occidentalis P1 plants and 15-30% infected Nicotiana clevelandii plants. Particle bombardment was also used successfully to infect N. clevelandii plants with in vitro RNA transcripts of full-length cDNA of BWYV.

Animals↗
PubMed2001

Delayed hypersensitivity to cefazolin: report on a case involving lymphocyte transformation studies with different cephalosporins.

BACKGROUND: A cell-mediated immunopathogenic mechanism has been demonstrated in only a few cases of cutaneous reactions to systemically administered cephalosporins. OBJECTIVE: The aim was to investigate the pathogenic mechanism of a maculopapular rash experienced by a subject during cefazolin therapy. METHODS AND RESULTS: Prick, intradermal, and patch tests were carried out using penicillin determinants, ampicillin, amoxicillin, cefazolin, cephalothin, cefuroxime, ceftazidime, and ceftriaxone. Those tests for penicillin G and its determinants, as well as for ampicillin and amoxicillin, were negative. The patient displayed patch-test and delayed intradermal-test positivity to all the cephalosporins tested. No specific immunoglobulin E antibodies were found for penicillins or cefazolin. The lymphocyte-transformation-test results were negative for all the penicillins tested and showed a positive concentration-effect curve for cefazolin, ceftazidime, and ceftriaxone at concentrations up to 50 microg/mL. At 100 microg/mL the responses decreased with all the cephalosporins tested. Challenges with penicillin G and amoxicillin were well tolerated, but the challenge with cefazolin was positive. CONCLUSIONS: The data of this case demonstrate delayed hypersensitivity to cefazolin. Patch tests and delayed-reading intradermal tests can be a simple and effective means of diagnosing this type of reaction. Both in vivo and in vitro studies indicate that the responses were directed toward a determinant shared by all cephalosporins, but not by penicillins. The concentration of the cephalosporins used for the in vitro lymphocyte stimulation was critical, because at the concentrations normally used to test other beta-lactams the response decreased. This phenomenon may be attributable to an immunosuppressive, rather than toxic, effect.

Adult↗
PubMed2001

Diagnostic evaluation of a large group of patients with immediate allergy to penicillins: the role of skin testing.

BACKGROUND: Penicillin is no longer the most commonly prescribed beta-lactam, and the pattern of reactions has changed. We studied the diagnostic value of skin testing in penicillin-allergic subjects from a population where benzylpenicillin is not now the most frequently used beta-lactam. METHODS: Patients with a history of immediate allergic reactions to penicillins were studied with: skin tests with major and minor determinants of benzylpenicillin (BPO/MDM), amoxicillin, and ampicillin; in vitro determination of specific IgE; and controlled administration for those with a positive history but negative skin and in vitro tests. A reaction was considered immediate when symptoms appeared within a maximum of 1 h after drug intake. RESULTS: After testing, 290 patients (71% having anaphylaxis and 29% having urticaria) proved to be allergic. Amoxicillin was involved in 64.8% and benzylpenicillin in 2.8% of the patients. Skin test positivity to at least one determinant appeared in 70% of cases, amoxicillin being the most frequent. The overall sensitivity decreased markedly when only BPO and MDM were considered. In 13.1% of patients, the diagnosis was established by in vitro test and in 16.9% by controlled administration. Of the 290 patients, 42.1% were positive to determinants generated from benzylpenicillin and 57.9% were selective responders. CONCLUSIONS: Sensitivity of skin tests to BPO was lower than reported, being partly replaced by minor determinants, mostly amoxicillin. The incorporation of additional reagents and the development of new tests are required, and these will probably change as the patterns of consumption vary.

Amoxicillin↗