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  • Author: Giovanni Di Giuseppe x
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Abstract

A multiparticle quantum superposition state has been generated by a novel phase-selective parametric amplifier of an entangled two-photon state. This realization is expected to open a new field of investigations on the persistence of the validity of the standard quantum theory for systems of increasing complexity, in a quasi decoherence-free environment. Because of its nonlocal structure the new system is expected to play a relevant role in the modem endeavor on quantum information and in the basic physics of entanglement. - Pacs: 03.65.Bz, 03.67.-a, 42.50.Ar, 89.70.+C

Abstract

In recent years, it has become evident that many neurotransmitters and endogenous ligands differentially modulate synaptic γ-aminobutyric acid type A receptors (sGABAARs) and extrasynaptic GABAAR (eGABAARs). In this mini-review, we will summarize the available evidence on the ability of the monoamines serotonin (5-HT), noradrenaline (NA), and, in particular, dopamine (DA) to alter the functional response of eGABAARs, thus either increasing or decreasing tonic GABAA inhibition. Although this field of research is still in its infancy, it has already been demonstrated that eGABAARs show a nucleus-selective and neuronal-type-selective regulation by monoamines in a way that differs from that of sGABAARs. Further work will undoubtedly advance our knowledge of the intricate talk between monoamines and eGABAAR and may ultimately provide new leads for the treatment of neurological and neuropsychiatric disorders, where alteration in GABAAR function is one of the underlying causes.

Abstract

Haemophilia A is the most common inherited bleeding disorder caused by defects in the F8C gene that encodes coagulation factor VIII. This X-linked recessive disorder occurs in approximately 1:5000 males. Haemophilia A is diagnosed based on normal prothrombin time, altered activated partial thromboplastin time and reduced factor VIII activity in plasma. Carrier females are usually asymptomatic and can be identified only by molecular analysis. The most frequent mutations in F8C are intron 22 and 1 inversions, which occur in approximately 50% and 5% of patients, respectively, with a severe phenotype. Large gene deletions are observed in approximately 5% of alleles from patients with severe haemophilia A. The remaining severe cases and all moderate and mild cases result from numerous point mutations and small insertions/deletions, which are de novo mutations in one-third of cases. Thus, molecular diagnosis of carrier status and prenatal diagnosis in families without intron 22 or 1 inversions is based on scanning techniques or gene sequencing. When the disease-causing mutation cannot be identified, molecular diagnosis is performed by linkage analysis of several DNA polymorphic markers linked to F8C. Given the clinical heterogeneity among haemophilic patients, many groups, including our own, have examined the relationships between prothrombotic gene variants and haemophilic phenotype to investigate whether prothrombotic gene variants modify clinical expression of the disease.

Clin Chem Lab Med 2007;45:450–61.

Abstract

Thanks to its typical expression, haemophilia can be identified in writings from the second century AD. Haemophilia B, an X-linked recessive bleeding disorder due to factor IX (FIX) deficiency, has an incidence of about 1:30000 live male births. The factor 9 (F9) gene was mapped in 1984 on Xq27.1. Haemophilia is diagnosed from prothrombin time, activated partial thromboplastin time, and FIX levels. Carrier females are usually asymptomatic and must be identified only with molecular analysis. Linkage analysis of F9 polymorphisms is rapid and inexpensive but limited by non-informative families, recombinant events, and the high incidence of germline mutations; thus, various procedures have been used for the direct scan of F9 mutations. We set up a novel denaturing high performance liquid chromatographic procedure to scan the F9 gene. This rapid, reproducible procedure detected F9 mutations in 100% of a preliminary cohort of 18 haemophilia B patients. Parallel to the development of more efficient diagnostic tools, the life expectancy and reproductive fitness of haemophilic patients have greatly improved and will continue to improve thanks to the use of less immunogenic recombinant FIX. Hopefully, new approaches based on gene therapy now being evaluated in clinical trials will revolutionise haemophilia B treatment.

Abstract

Background: Haemophilia A and B (HA, HB) are the most frequent X-linked bleeding diseases; two-thirds of cases are severe.

Methods: We counselled 51 couples for prenatal diagnosis (PD) of haemophilia. In 7/51 (13.7%) cases, the couple decided not to undergo PD because counselling revealed that they were carriers of a mild form of the disease, while we performed 44 PD for severe HA (36 cases) or HB (8 cases). The indication for PD was a haemophilic child (30/44, 68.2%) or an affected family member (12/44, 27.3%); in two cases the non-carrier mother of isolated haemophilic patients requested PD because of the risk of mosaicism.

Results: We completed PD in 43/44 cases; in one case, the prenatal sample was contaminated by maternal DNA; however, molecular analysis revealed the female sex of the foetus. We performed PD for 16 of the 36 couples at risk of HA (44.4%) by analysing the intron (IVS)22 inversion; in 1/36 cases (2.8%) the mother had the IVS1 inversion, and in 8/36 (22.2%) the family mutation was identified by sequencing; in 11/36 (30.6%) cases the family mutation was unknown, and PD was performed by linkage (no recombination nor uninformative cases occurred). For HB, in 6/8 (75.0%) cases, PD was performed by DHPLC or by sequencing; in 2/8 cases we tested intragenic markers (again with no cases of recombination or uninformative families).

Conclusions: PD in well-equipped laboratories, and multidisciplinary counselling are an aid to planning reproductive and early therapeutic strategies in families with severe haemophilia.

Abstract

In this paper we review the double covers method with constrained BV functions for solving the classical Plateau’s problem. Next, we carefully analyze some interesting examples of soap films compatible with covers of degree larger than two: in particular, the case of a soap film only partially wetting a space curve, a soap film spanning a cubical frame but having a large tunnel, a soap film that retracts to its boundary, and various soap films spanning an octahedral frame.

Abstract

The management of chronic pilonidal disease remains controversial, but recently, new minimal invasive approaches have been proposed. Whereas in the conventional surgical treatment an elliptical wedge of skin and subcutaneous tissue is created to remove the sinus and its lateral tracks, the basis for our new treatment is to create a minimal elliptical wedge of the subcutaneous tissue, including all the inflamed tissue and debris while leaving the overlying skin intact.

The mechanism of an endoscopic approach relies on use of the endoscope without cutaneous tissue damage. Advantages include shorter operative time and time to discharge, which impact resource management in both primary and secondary care: patients undergoing endoscopic technique have a high satisfaction rate, probably due to the low level of postoperative pain and early return to work and daily activities. However, it is mandatory that further studies would analyze surgical approaches to pilonidal sinus disease (PSD) with a consistent and adequate follow-up of at least 5 years. Both sinusectomy and endoscopic approach to PSD were found to be safe and effective compared with conventional techniques. Publishedresults of studies of newer approaches have demonstrated a low short-term complication rate, comparable to conventional surgery results.