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E Diamanti

Publications and source records attributed to E Diamanti.

14 recordsLinked to original sources
PubMed2004

Quantum teleportation with a quantum dot single photon source.

We report the experimental demonstration of a quantum teleportation protocol with a semiconductor single photon source. Two qubits, a target and an ancilla, each defined by a single photon occupying two optical modes (dual-rail qubit), were generated independently by the single photon source. Upon measurement of two modes from different qubits and postselection, the state of the two remaining modes was found to reproduce the state of the target qubit. In particular, the coherence between the target qubit modes was transferred to the output modes to a large extent. The observed fidelity is 80%, in agreement with the residual distinguishability between consecutive photons from the source. An improved version of this teleportation scheme using more ancillas is the building block of the recent Knill, Laflamme, and Milburn proposal for efficient linear optics quantum computation.

Journal Article↗
PubMed2001

Bone resorption is increased in young adults with thalassaemia major.

Bone disease in patients with thalassaemia major is a multifactorial and still poorly understood process. The present study evaluated 45 thalassaemic patients using dual X-ray absorptiometry at three sites (lumbar spine, head of femur and forearm) to assess bone mineral density, in parallel with a series of biochemical markers to measure bone formation and bone resorption. To identify possible interfering factors, our patients were grouped according to whether or not they needed transfusion therapy; the presence of hypogonadism was also considered. Our results showed that patients on regular transfusions had a markedly low bone mineral density in contrast to those not requiring blood support and that this finding was more pronounced in the hypogonadic group, irrespectively of sex. The decrease of bone mineral density values was more prominent in the forearm, thus making this site particularly interesting for such studies. Bone formation, as evidenced by the levels of serum alkaline phosphatase and osteocalcin, did not appear to be impaired, while bone resorption was grossly increased in all patient groups. The latter process was clearly evident using the recently introduced measurement of the urinary N-terminal peptides of collagen type I, the sensitivity of which has already been established in other groups of osteoporotic patients. Our conclusion is that, in spite of the severe bone destruction that occurs in thalassaemia major, the fact that bone formation remains intact calls for a more intensive treatment comprising hormonal replacement, bisphosphonates and other agents.

Absorptiometry, Photon↗
PubMed1998

Antigenic and molecular characterization of wild type 1 poliovirus causing outbreaks of poliomyelitis in Albania and neighboring countries in 1996.

Mass vaccination has led poliomyelitis to become a rare disease in a large part of the world, including Western Europe. However, in the past 20 years wild polioviruses imported from countries where polio is endemic have been responsible for outbreaks in otherwise polio-free European countries. We report on the characterization of poliovirus isolates from a large outbreak of poliomyelitis that occurred in Albania in 1996 and that also spread to the neighboring countries of Yugoslavia and Greece. The epidemics involved 145 subjects, mostly young adults, and caused persisting paralysis in 87 individuals and 16 deaths. The agent responsible for the outbreak was isolated from 74 patients and was identified as wild type 1 poliovirus by both immunological and molecular methods. Sequence analysis of the genome demonstrated the involvement of a single virus strain throughout the epidemics, and genotyping analysis showed 95% homology of the strain with a wild type 1 poliovirus strain isolated in Pakistan in 1995. Neutralization assays with both human sera and monoclonal antibodies were performed to analyze the antigenic structure of the epidemic strain, suggesting its peculiar antigenic characteristics. The presented data underline the current risks of outbreaks due to imported wild poliovirus and emphasize the need to improve vaccination efforts and also the need to implement surveillance in countries free of indigenous wild poliovirus.

Adolescent↗
PubMed1996

Selective IgA deficiency in a patient with Hashimoto's thyroiditis. Case report.

We describe a case of Hashimoto's thyroiditis in which, eight years after initial diagnosis, an isolated (selective) IgA deficiency was detected. It is not clear which of these two conditions followed the other (both aetiologically and chronologically); indications and arguments for and against both hypotheses are discussed.

Adult↗
PubMed1996

An epidemiological study on viral infantile diarrhoea in Tirana.

During the period May 1993-April 1994, an epidemiological survey was conducted on enteric viruses which cause gastroenteritis in infants and young children in Tirana, Albania. Specimens from 321 cases were screened by direct electron microscopy and by an enzyme-linked immunosorbent assay specific for rotavirus group A antigen. By ultrastructural analysis, rotaviruses were detected in 10.3% of cases and adenoviruses in 0.6%, whereas small round structured viruses and small round viruses were found in 2.8% and 2.2% of cases, respectively. Different percentages of rotavirus excretors were revealed by enzyme-linked immunosorbent assay (12.15%) and electron microscopy. Samples rotavirus-positive in at least one of these assays were also analyzed by agglutination of latex particles and electron microscopy results were confirmed. Analysis of electron microscopy-positive samples by rotaviral RNA polyacrylamide gel electrophoresis showed five different long electropherotypes of rotavirus among which a single, largely predominant electropherotype (65.5%) was observed.

Adenoviridae↗
PubMed1995

Follow-up of very low birth weight infants after erythropoietin treatment to prevent anemia of prematurity.

OBJECTIVE: Treatment with recombinant human erythropoietin (rHuEPO) stimulates erythropoiesis and reduces the need for transfusions in hospitalized preterm infants. The aim of our study was to follow very low birth weight infants after the initial 6 weeks of rHuEPO treatment. DESIGN AND METHODS: We randomly assigned 97 very low birth weight infants with a gestational age of 31 weeks or less and birth weight of 1500 gm or less to receive rHuEPO, 300 units/kg per week (erythropoietin (EPO) 300, n = 33), rHuEPO, 750 units/kg per week (EPO 750; n = 28), or no treatment (control, n = 36). The rHuEPO was administered from the first week of life for 6 weeks. After EPO therapy was discontinued, 75 neonates were followed weekly until discharge and at 3, 6, and 12 months of age. RESULTS: Mean numbers (+/- SD) of packed erythrocyte transfusions per patient from the time rHuEPO therapy was discontinued until discharge were 0.38 +/- 0.64 (EPO 300), 0.23 +/- 0.52 (EPO 750), 0.9 +/- 1.1 (control) (p < 0.05 in both EPO groups vs control). Mean reticulocyte counts at the sixth week were 6% +/- 2.2% (EPO 300), 6.9% +/- 2.2% (EPO 750), and 3.1% +/- 2.6% (control) in the three groups (p < 0.01 in both EPO groups vs control), and at the eighth week were 4.7% +/- 2.8% (EPO 300), 5.4% +/- 2.7% (EPO 750), and 2.6% +/- 2.2% (control) (p < 0.01 in both EPO groups vs control). Serum ferritin levels were significantly higher at the sixth week, and the percentage of hemoglobin F was significantly lower at 6, 8, and 10 weeks in the control group versus EPO groups. At 3, 6, and 12 months of age, there were no differences in reticulocytes, ferritin, HbF, and growth among groups. CONCLUSION: Preterm infants who received rHuEPO had a normal pattern of erythropoiesis after the drug was discontinued. These data provide strong evidence that the anemia of prematurity is the result of a transient developmental abnormality in EPO production.

Anemia, Neonatal↗
PubMed1995

Accuracy of anthropometric measurements in predicting symptomatic SGA and LGA neonates.

Mid-arm circumference, mid-arm circumference/head circumference ratio, ponderal index and skinfold thickness at five sites (biceps, triceps, quadriceps, subscapular and flank) were measured in 91 small-for-gestational-age (SGA) and 101 large-for-gestational-age (LGA) neonates to investigate their accuracy in identifying neonates at high risk of complications resulting from disturbed intrauterine growth. Thirty-one of 91 SGA and 19 of 101 LGA neonates who developed hypoglycaemia and/or polycythaemia were regarded as symptomatic. Mean values of all of the anthropometric parameters differed significantly between symptomatic and asymptomatic SGA or LGA neonates. The quadriceps skinfold thickness was the most sensitive index in predicting symptomatic SGA and LGA neonates (sensitivity 0.93 and 0.95, respectively). The mid-arm circumference was also a very sensitive index in predicting symptomatic SGA neonates (sensitivity 0.94) but its specificity was extremely low (0.20). The rest of the parameters showed lower sensitivity than quadriceps skinfold thickness associated with similarly low specificity and validity. The findings of this study indicate that the quadriceps skinfold thickness is the most reliable index for use as a screening test for clinical evaluation of SGA and LGA neonates who are likely to develop complications as a result of disturbed intrauterine nutrition.

Anthropometry↗
PubMed1995

Concentrations of main serum opsonins in early infancy.

The evolution of the main serum opsonins in neonates and infants of varying gestational age was investigated to provide reference values for these opsonins in early infancy. Serum concentrations of immunoglobulins, IgG subclasses, C3, C4 and fibronectin were serially measured from birth until the age of 6 months in term and preterm infants. Measurements were performed by rate nephelometry. Five hundred and sixty six neonates (gestational age 26-41 weeks) were examined at birth, 233 at 1 month, 218 at 3 months, and 147 at 6 months, respectively. The same measurements were performed in 54 pairs of neonatal/maternal samples and in 230 apparently healthy adults. Gestational age had a significant impact on serum IgG, IgG subclasses, C3 and C4 up till the third month, and on fibronectin until the first month. No such impact was observed for IgA and IgM. Sixteen per cent of the neonates had IgM concentrations higher than 0.2 g/l at birth, suggesting that the critical concentration of serum IgM at birth for suspected intrauterine infection should be reconsidered. Concentrations of all opsonins at birth were significantly lower than adult reference values. They only approached or even reached adult values by the third or the sixth month. Data from analysis of the neonatal and the corresponding maternal sera indicate that there is a preferential active transplacental transport of IgG subclasses in the order of IgG1, IgG3, IgG2 and IgG4. These results show that concentrations of immunoglobulins, C3, C4 and fibronectin undergo changes during the first months of life, depending not only on the infants' postnatal age but also on gestational age.

Complement C3↗
PubMed1995

Serum concentrations of 10 acute-phase proteins in healthy term and preterm infants from birth to age 6 months.

Aiming to define the evolution pattern of 10 acute-phase proteins in early infancy, we measured nephelometrically the serum concentrations of albumin, prealbumin, retinol-binding protein, transferrin, ceruloplasmin, hemopexin, haptoglobin, alpha 1-acid glycoprotein, alpha 2-macroglobulin, and alpha 1-antitrypsin in 395 term and preterm infants (gestational ages 26-41 weeks). Measurements were performed within 24 h after birth and then at the end of 1 (n = 171), 3 (n = 155), and 6 (n = 90) months afterwards. Data obtained from 250 healthy adults were used as adult reference values. All proteins increased progressively with postnatal age, except for alpha 1-antitrypsin, which remained stable from birth to the 6th month. Concentrations of almost all measured proteins were significantly lower in preterm than in term infants in the first 3 months. Compared with adult values, alpha 2-macroglobulin and alpha 1-antitrypsin were higher in infants throughout the 6 months. The other proteins were significantly lower at birth than adult values but after 6 months, only albumin, prealbumin, retinol-binding protein, and alpha 1-acid glycoprotein still remained lower in infants. Thus both gestational and postnatal age should be considered when interpreting concentrations of these proteins in early infancy.

Acute-Phase Proteins↗
PubMed1995

Electropherotypes of rotavirus strains causing gastroenteritis in infants and young children in Tirana, Albania, from 1988 to 1991.

During 1988-1991, an epidemiological survey was conducted in Tirana (Albania) on group A rotavirus strains which cause gastroenteritis in infants and young children. Rotaviruses were detected in 312 of 1,241 (25.1%) examined specimens from children with acute diarrhoea. Viruses were detected throughout the study period. Among the 72 rotavirus strains tested for double-stranded RNA (dsRNA) electrophoretic migration pattern, 9 different electropherotypes were recognized, 1 of those being more frequent than the others. At the beginning and at the end of the examined period (1988 and 1990-1991) two different long electropherotypes were predominant, whereas in 1989 (middle period) short electropherotypes were common indicating an involvement of virus strains with short electropherotypes in hospitalization-requiring diarrhoeas occurring in the area surveyed in that year.

Age Factors↗
PubMedDate not supplied

Surveillance of suspected poliomyelitis in Albania, 1980-1995: suggestion of increased risk of vaccine associated poliomyelitis.

Surveillance of suspected poliomyelitis cases was conducted in Albania from 1980 through 1995. A total of 93 cases were reported, 11 of which were clinically defined as poliomyelitis cases according to WHO criteria. Poliovirus was isolated from six subjects who were defined as contact vaccine-associated cases. Characterization of isolates by both antigenic and molecular methods showed that, in all cases, the disease was associated with type 2 or 3 polioviruses of vaccine origin with retromutations known to be associated with loss of Sabin attenuated phenotype. Infection occurred despite the fact that all patients had records of previous immunization with oral polio vaccine (OPV), suggesting a failure of vaccination. Four of the five patients from which poliovirus could not be isolated were classified as possible recipient vaccine-associated poliomyelitis on the basis of serology data (presence of antibodies against all three polioviruses) and the temporal association between the latest dose of vaccine received and onset of paralysis. Virological investigation on healthy contacts of the poliomyelitic patients yielded the isolation of a further 12 Sabin-like polio revertant viruses, mostly type 2 and 3. A detailed study of the non-polio acute flaccid paralysis (AFP) cases and their healthy contacts revealed the presence of several enteroviruses, namely Echo, coxsackie and, in three cases type 2 or 3 Sabin-like polioviruses. Overall, these data suggest the absence of circulation of wild-type poliovirus in Albania from 1980 to 1995, before the recent outbreak of poliomyelitis in 1996, and emphasize the need for active surveillance of AFP and laboratory characterization of virus isolates to monitor vaccination efficacy.

Adolescent↗