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G Veneziano

Publications and source records attributed to G Veneziano.

At least 19 recordsLinked to original sources

Supersymmetry relics in one-flavor QCD from a new 1/N expansion.

We suggest a new large-N(c) limit for multiflavor QCD. Since fundamental and two-index antisymmetric representations are equivalent in SU(3), we have the option to define SU(N(c)) QCD keeping quarks in the latter. We can then define a new 1/N(c) expansion (at a fixed number of flavors N(f)) that shares appealing properties with the topological (fixed N(f)/N(c)) expansion while being more suitable for theoretical analysis. In particular, for N(f)=1, our large-N(c) limit gives a theory that we recently proved to be equivalent, in the bosonic sector, to N=1 supersymmetric gluodynamics. Using known properties of the latter, we derive several qualitative and semiquantitative predictions for N(f)=1 massless QCD that can be easily tested in lattice simulations. Finally, we comment on possible applications for pure SU(3) Yang-Mills theory and real QCD.

Journal Article↗

Causal entropy bound for a spacelike region.

The identification of a causal-connection scale motivates us to propose a new covariant bound on entropy within a generic spacelike region. This "causal entropy bound," scaling as sqrt[EV], and thus lying around the geometric mean of Bekenstein's S/ER and holographic S/A bounds, is checked in various "critical" situations. In the case of limited gravity, Bekenstein's bound is the strongest while naive holography is the weakest. In the case of strong gravity, our bound and Bousso's holographic bound are stronger than Bekenstein's, while naive holography is too tight, and hence typically wrong.

Journal Article↗

Congenital dyserythropoietic anaemia type II associated with a new type of G6PD deficiency (G6PD Gabrovizza).

A 6-year-old boy with chronic haemolytic anaemia was found to have glucose 6-phosphate dehydrogenase (G6PD) deficiency and the morphological, ultrastructural and serological features of congenital dyserythropoietic anaemia (CDA) type II. The patient's mother was heterozygous for G6PD deficiency. G6PD from the patient's red cells, upon partial purification and full characterization, was found to be a new variant designated G6PD Gabrovizza. We conclude that two distinct genetic abnormalities coexisted in this patient. We suggest that CDA type II may become clinically more expressed when another abnormality of the erythrocytes coexists.

Anemia, Dyserythropoietic, Congenital↗

High dose bolus methylprednisolone for the treatment of acute graft versus host disease.

Nineteen patients with acute graft versus host disease (GvHD) following bone marrow transplantation (BMT) were treated with high dose bolus 6-methylprednisolone (BMPr), at the dose of 20 mg/kg/day i.v. for the first 3 days, 10 mg/kg/day i.v. for the following 4 days, and then at doses gradually tapered down to 1 mg/kg/day. All patients except one, who was given preventive BMPr 5 mg/kg/day i.v. on alternate days, were placed on preventive methotrexate therapy after BMT. Sixteen patients were grafted with an HLA matched, and three patients with an HLA mismatched marrow. Overall complete response rate in the HLA matched group was 43%, with an additional 50% showing a partial response. In the HLA mismatched group there were no responses and all three patients proved refractory to BMPr. With respect to organ involvement the complete and partial response rates were respectively 50% and 33% in the skin, 36% and 28% in the liver, 18% and 55% in the gut. Six of sixteen patients in the HLA matched group and none of the three in the HLA mismatched group are surviving. Thirteen patients died: nine patients for causes directly or indirectly related to GvHD, four of other causes (relapse, rejection, hemorrhage and idiopathic interstitial pneumonia). Side effects of BMPr consisted in hyperglicemia, and steroid associated gastritis in 2/3 of the patients, both of which responded well to conventional treatment. This study indicates that high dose BMPr is an effective form of treatment for established acute GvHD, and has no major side effects. The efficacy of BMPr is less clear in recipients of HLA mismatched grafts.

Adolescent↗

[Use of Blasto-Kit for cytogenetic analysis].

We have considered the possibility of using commercial Blasto-Kit, with AB pool, for chromosome analysis. Comparative researches have been made between Blasto-Kit-AB and Blasto-Kit in which AB serum was replaced by FCS. Using 0.1 ml of whole blood lymphocyte response to PHA after incorporation of thymidine H3 and the mitotic rate obtained have been evaluated. The Blasto-Kit-AB gives better results if compared with Blasto-Kit-FCS either in lymphocyte response to PHA or in chromosome analysis.

ABO Blood-Group System↗