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Biomedical subjects

C Delfini

Publications and source records attributed to C Delfini.

At least 37 records · Page 2Linked to original sources

PCR analysis of HBV infected sera: relationship between expression of pre-S antigens and viral replication.

In order to determine the biological significance of the pre-S antigens in HBV infection, HBsAg sera were tested for the presence of pre-S1 and pre-S2. HBV DNA was detected by spot-hybridization and PCR. The data show a complete correlation between pre-S antigenemia and HBV DNA replication in anti-HBe positive cases. PCR but not spot-hybridization was adequately sensitive to also detect HBV DNA in roughly half of the preS negative sera as well. Thus PCR appears to be a valuable technique for detection of potentially infectious anti-HBe carriers.

DNA, Viral↗

Increased serum concentrations of tumour necrosis factor in beta thalassaemia: effect of bone marrow transplantation.

AIMS: Serum concentrations of tumour necrosis factor-alpha (TNF) were determined in beta thalassemic patients before and after bone marrow transplantation (BMT) to evaluate whether changes in TNF concentrations after BMT were related to immune mediated complications. METHODS: Serum TNF concentrations were determined by enzyme linked immunoassay (EIA) in paired samples from 71 patients with beta thalassemia before and after BMT. Serial samples from 13 patients were also studied for up to six months after BMT. Forty one normal healthy children matched for sex and age were studied as controls. RESULTS: beta thalassemic patients had high serum TNF concentrations before transplantation compared with controls. These were not related to sex, age, duration of disease, number of blood transfusions, transferrin concentrations or splenectomy. DQw1 positive patients showed significantly lower TNF concentrations than non-DQw1 cases. Patients with severe liver fibrosis had significantly higher TNF concentrations. No correlation was found between TNF values and BMT outcome before transplantation but TNF alpha values fell significantly after BMT. The decrease persisted only in patients with successful engraftment. In serial samples studied for up to six months after BMT, TNF values decreased but in four out of five patients with graft rejection and in all five with acute graft versus host disease (GVHD) sharp increases occurred at the time of clinical symptoms. No correlation was found between the degree of GVHD and serum TNF-alpha concentrations nor between TNF-alpha concentrations after BMT and the presence of bacterial, viral, and fungal infections. CONCLUSIONS: About 50% of beta thalassemic patients have increased serum TNF, and the changes after BMT are related to the occurrence of immune mediate complications. The persistence of low TNF concentrations after successful engraftment may be due to the preparative regimen and the lack of adverse immune reactions.

Bone Marrow Transplantation↗

Serum amyloid A protein concentration in bone marrow transplantation for beta thalassaemia.

AIMS: To investigate whether serum amyloid A protein (SAA) and C-reactive protein (CRP) concentrations could be used in the management of beta thalassaemic patients undergoing bone marrow transplantation (BMT). METHODS: Serum SAA and CRP concentrations were determined in paired samples from 66 patients with beta thalassaemia before and after BMT. Serum SAA concentrations were determined by an enzyme linked immunoassay (EIA); serum CRP concentrations were determined by a nephelometric assay. RESULTS: Serum SAA concentrations before transplantation were significantly higher in the group that subsequently rejected the transplant than the group without complications. SAA concentrations increased after BMT in acute graft versus host disease (GvHD) and rejection. No significant increase in SAA or CRP was found in chronic GvHD. Increases in serum in SAA and CRP concentrations were not related to concomitant infection episodes. CONCLUSIONS: The different acute phase response in acute GvHD and rejection compared with chronic GvHD suggests that different immunopathogenic mechanisms are responsible.

Acute Disease↗

Levels of pre-S antigens and HBV DNA in sera from high and low viremic HBV carriers.

The biological and clinical significances of pre-S antigens and HBV replication were investigated. Some 125 sera, 28 from HBeAg and 97 from anti-HBe-positive HBsAg, carriers were studied. The aim was to verify whether pre-S antigens could be expressed in serum in complete absence of viremia. Pre-S proteins, determined by an enzyme immunoassay, were found in sera regardless of the presence of HBV DNA, as detected by spot-hybridization. The sera without detectable HBV DNA were investigated further by PCR using specific primers for the S and C regions of HBV. PCR analysis of samples revealed that 4 out of 5 HBeAg and 33 out of 41 (80.5%) anti-HBe positive sera contained HBV-amplified sequences of S and C regions. Pre-S antigen values correlated well with the amounts of HBV DNA in serum detected by PCR in anti-HBe-positive subjects with high titers of pre-S antigens (10(4)-10(6)). In addition, PCR highlighted the presence of HBV DNA sequences in 8 out of 17 (47.1%) pre-S-negative HBsAg-positive sera.

Antibodies, Monoclonal↗

Clearance of hepatitis B virus DNA and pre-S surface antigens in patients with markers of acute viral replication.

To clarify the relationship between the pre-S antigens and other serological markers of hepatitis B virus (HBV) replication, we followed up 27 patients: 21 presented with symptoms of acute hepatitis (two progressed to chronicity) and six suffered from chronic hepatitis. Pre-S1, pre-S2, HBV DNA, IgM antihepatitis core antigen (HBc), hepatitis B e antigen (HBeAg), and anti-HBe were detected in about 200 sera serially collected at different times for at least 6-12 months from the onset of clinical observation. In the early symptomatic phase of acute hepatitis, the pre-S1 and pre-S2 antigens were present in 95% of the cases and correlated well with high levels of alanine-transferase (ALT) and IgM anti-HBc, while HBV DNA was present in the sera of only six (28.6%) patients (P less than 0.0001). This was the first marker to disappear (1 month after the initial stage). All of the HBV DNA-positive patients were also HBeAg positive, whereas no HBeAg-negative subjects were found with serum HBV DNA. In the six chronic patients, pre-S antigens were always present independently of the HBeAg/anti-HBe status; HBV DNA was detected in three of them, even if transiently, and in two of these it reappeared together with pre-S2 epitope. The follow-up data suggest that, in acute hepatitis, the clearance of pre-S antigens can be considered as a prognostic index of clinical resolution and that, in chronic hepatitis, the persistence of pre-S antigens seems to indicate progression of the disease. In particular, pre-S2, in patients in whom it is intermittent, can be considered as an index of reactivation.

Acute Disease↗

Genotypic analysis of engraftment in thalassemia following bone marrow transplantation using synthetic oligonucleotides.

DNA hybridization with synthetic oligonucleotide probes was used to assess engraftment in 19 thalassemic patients who received bone marrow grafts from their respective healthy HLA-identical siblings. Three oligomers complementary to the tandem repetitive sequences of different hypervariable regions of human DNA were designed so as to produce simple RFLP (restriction fragment length polymorphism) patterns. Each probe hybridizes to one or two bands in HinfI-digested genomic DNA. The combined use of these three probes allowed a discrimination between all the HLA-identical siblings tested. Both donor-specific and recipient-specific DNA fragments existed in 18 out of the 19 sibling pairs studied. One pair possessed only a donor-specific fragment. DNA analysis at an early stage after the graft detected donor-specific fragments in 15 out of 19 patients, recipient-specific fragments in three patients and a mix of recipient and donor fragments in one patient. At a later stage this patient possessed donor-specific fragments only. Follow-up DNA analysis confirmed these findings. Thus 16 patients continued to display donor-specific fragments over 60 days post-transplant. These DNA data showed strong correlation with the clinical status of the patients as well as with other markers of engraftment including cytogenetics and hemoglobin synthesis. The patients who showed donor-specific fragments over 60 days have been free of thalassemic symptoms for over 300 days. Moreover, in 11 cases it was possible to predict the fate of the graft within 15 days after transplantation. In conclusion, the use of the three synthetic oligonucleotide probes provides a powerful tool in documenting engraftment in bone marrow transplantation.

Adolescent↗

[The volume of the cerebral ventricles in vertebrates].

The relative volume of the brain ventricles in Vertebrates decreases from fishes to mammals and from embryos to adults. The comparison of Chondrichthyans and Teleosteans shows that the high encephalization of the former is not only due to the difference between the relative volume of the ventricular spaces.

Aging↗

Marrow transplantation in patients with advanced thalassemia.

In a study of the outcome of marrow transplantation in patients with advanced thalassemia, 40 patients with homozygous beta-thalassemia who were 8 to 15 years of age (median, 10) received HLA-identical allogeneic marrow after treatment with busulfan and cyclophosphamide. Twenty-eight of the 40 patients were alive and free of disease 260 to 939 days after transplantation, and 2 patients were alive with thalassemia 372 and 1133 days after transplantation. The actuarial probabilities of survival and of disease-free survival at two years were 75 percent and 69 percent, respectively. Ten patients (25 percent) died. Three died of cardiac failure, interstitial pneumonitis, or septicemia within 14 days of transplantation. Three died of infectious complications associated with acute graft-versus-host disease at 46 to 97 days, and two died of infectious complications of chronic graft-versus-host disease at 249 and 290 days. Two patients had transplant rejection and died with marrow aplasia 115 and 192 days after transplantation. One patient had rejection after four months and while the marrow was aplastic underwent a successful second transplantation; the patient was alive without thalassemia 624 days after the first transplantation. The actuarial probability of grade 2 or higher acute graft-versus-host disease in the 32 patients with initial sustained engraftment was 35 percent. Three patients had chronic graft-versus-host disease, which was fatal in two and still active on day 710 in the third. We conclude that bone marrow transplantation can potentially save patients with advanced thalassemia from an otherwise inexorable progression to death from the complications of blood transfusions. The ultimate outcome in this group of patients must await a longer follow-up.

Adolescent↗

DNA methylases separated through the HeLa cell cycle methodology show allosteric properties.

Two DNA methylases (DNAmets) can be separated through the cell cycle. The first appears as a minor peak in G1, the second as a major peak in S. Both enzymes protect from HpaII a plasmid (H31), constructed with the pBR322 vector (4.3 kbp) and the inverted A gamma fragment of the human globin gene (3.5 kbp), inserted at its HindIII site (the vector carries several HpaII sites, the insert only one HpaII site). DNAmets G1 and S show distinct Km values and different kinetics vs the ionic strength of the medium, while their Michaelis-Menten and Lineweaver-Burk plots are sigmoidal and hyperbolical curves, respectively. This is the first suggestion about the allosteric nature of the eukaryotic DNAmet system.

Allosteric Regulation↗

Detection of HBV infectivity by spot hybridization in HBeAg-negative chronic carriers: HBV DNA in sera from asymptomatic and symptomatic subjects.

DNA of hepatitis B virus (HBV DNA) in sera from HBeAg-positive carriers is now the most important and reliable marker of infectivity, but its significance in the progression of chronic hepatitis in anti-HBe carrier status is still under discussion. In this study, viral DNA was tested by a simplified spot hybridization method in sera of 206 HBeAg-negative Italian subjects. In a group of 153 HBsAg carriers, we found that 15.6% of anti-HBe-positive and 10.5% of anti-HBe-negative samples contained viral DNA. No HBV DNA was revealed in 38 HBsAg-negative nor in 15 anti-HBs-positive subjects with different serological markers of HBV. Viral DNA in sera of HBeAg-negative patients with severe chronic liver disease was correlated with increased alaninetransferase activity and IgM anti-HBc. Thus the presence of HBV DNA in these sera not only predicts which subjects are potentially infectious but also indicates chronic progression of hepatitis. Finally, viral DNA extracted from Dane particles of nine anti-HBe-positive sera was characterized by the Southern blot technique. The hybridization pattern shows bands indicating the presence of replicative intermediates.

Alanine Transaminase↗

Bone marrow transplantation in leukemia: experience of Pesaro.

The authors report the results of 113 patients who underwent bone marrow transplant for acute nonlymphoblastic leukemia, acute lymphoblastic leukemia and chronic myeloid leukemia in complete remission and relapse after different conditioning regimens.

Acute Disease↗

Limiting-dilution analysis for the determination of leukemic cell frequencies after bone marrow decontamination with mafosfamide or merocyanine 540.

To stimulate a leukemia remission marrow, cell suspensions of normal human bone marrow were mixed with human acute lymphoblastic or myelogenous leukemic cells of the CCRF-SF, Nalm-6, and K-562 lines. The cell mixtures were incubated in vitro with mafosfamide (AZ) or with the photoreactive dye merocyanine 540 (MC-540). A quantity of 10(4) cells of the treated suspensions was dispensed into microculture plates, and graded cell numbers of the line used to contaminate the normal marrow were added. Limiting-dilution analysis was used to estimate the frequency of leukemia cells persisting after treatment with the decontaminating agents. Treatment with AZ or MC-540 produced a total elimination (ie, 6 logs or 5.3 logs respectively) of B cell acute leukemia cells (CCRF-SB), whereas nearly 1.7 logs and 2 logs of K-562 acute myelogenous blasts were still present in the cell mixtures after treatment with MC-540 and AZ, respectively. Treatment of the Nalm-6-contaminated cell mixtures with AZ resulted in 100% elimination of clonogenic cells, whereas nearly 80% decontamination was obtained with MC-540. Our results suggest that treatment with AZ could be an effective method of eliminating clonogenic tumor cells from human bone marrow. MC-540, shown by previous studies to spare sufficient pluripotential stem cells to ensure hemopoietic reconstitution in the murine model and in clinical application, has comparable effects and merits trials for possible clinical use in autologous bone marrow transplantation.

Bone Marrow↗

HLA compatibility for patients with thalassemia: implications for bone marrow transplantation.

In order to evaluate the possibility of a patient with thalassemia finding an HLA-identical sibling donor, we performed an analysis of HLA antigens in families of thalassemic patients. The pattern distribution was not significantly different from the expected ratio 25:50:25. When the siblings were subdivided according to the age of the patients (under or over 5 years), the above pattern remained unmodified for both the age groups. The average size of the 129 thalassemic families was 2.4. Thus, taking into account that thalassemic patients have an average of 1.4 siblings and that the HLA genotype distribution is expected as such, HLA-matched siblings are available for 33% of the patients. Because an additional 8.5% of the patients were found HLA-phenotypically identical to one parent, the chance for a patient with thalassemia to find a suitable donor for bone marrow transplantation would be increased to 41.5%. Our preliminary data cannot be extrapolated to the overall Italian thalassemic population; however, it can be inferred that for a patient with thalassemia, the chance of finding a suitable donor for bone marrow transplantation is not reduced.

Bone Marrow Transplantation↗

Incidence of hepatitis B virus DNA and DNA-polymerase in sera of Italian asymptomatic carriers with the serological markers of HBV.

The presence of Hepatitis B virus (HBV) DNA in sera of patients with HBV related diseases is considered a reliable marker of virus active replication. In this paper HBV DNA was assayed by the molecular hybridization method with a 32P labeled nick translated HBV probe. The assay was positive in sera of 21 out of 22 HBeAg-positive and 4 out of 8 HBeAg-negative asymptomatic HBsAg carriers. 15 HBsAg-negative sera obtained from healthy donors showed no HBV DNA. Almost 80 per cent of HBeAg and HBV DNA positive sera revealed a DNA-polymerase activity. In order to determine the infectivity of HBsAg carriers, it appears that, whenever possible, the HBV DNA spot hybridization should be performed in conjunction with the DNA-polymerase, HBsAg and HBeAg tests.

Carrier State↗

[Encephalization of the marine lamprey, Petromyzon marinus (L.). Quantitative analysis of the principle brain subdivisions].

The measure of both the somatic weight (S) and the brain weight (E) on a sample of 13 adult individuals of Petromyzon marinus (L.) leads for this species to the determination of its brain-body weight coefficient of allometry and to the knowledge of its index of encephalization. The value of the first one is 0.556. Its locates the Sea-Lamprey at the highest level of a scale of decreasing values belonging one after the other to Chondrichthyes (0.551), to Teleost fishes (0.487), to Anurans (0.458), to Reptiles (0.43) and at last to Mammals (0.25). This result revalues our previous hypothesis which gives to this kind of statistic a phylogenetic meaning (RIDET et al. 1977). The index of encephalization has been arbitrarily fixed at the 10 value; it is the lowest of all the other indices previously known and consequently it points the Sea-Lamprey as the less encephalized Vertebrate species. The histological study carried out on the brain allows to the knowledge of the volumes of the main encephalic subdivisions. It leads to various results as: 1. The study the relative volumes (that is to say the volume of each subdivision expressed in percentage of the volume of the whole brain) emphasizes the olfactory bulbs and the Tegmentum + Medulla oblongata which have together the highest values amongst the brain percentages of Petromyzon marinus (and also of Lampetra planeri). This peculiarity has no equivalence in the brain structure of the other studied species of Vertebrates and we consider it as the expression of a primitive brain pattern. 2. The isoponderal indices locate also the Sea-Lamprey at the lowest level for all its encephalic subdivisions, as it was previously the case for the whole brain expressed by the index of encephalization. Such an unanimity seems also to be related to a fundamental brain organization. Comparisons between Petromyzon marinus, Lampetra planeri and Myxine glutinosa corroborate the paraphyletic status of the last one in the Agnathes. The differences pointed also between the two first species are less obvious but justify meanwhile a more detailed study of this group (Petromyzontidae) which shall be given soon.

Animals↗

Marrow transplantation for thalassaemia following busulphan and cyclophosphamide.

30 patients with homozygous beta-thalassaemia aged 6 months to 7 years received allogeneic marrow transplants following busulphan (Bu) and cyclophosphamide (Cy). Post-transplant immunosuppression was with methotrexate (MTX) or MTX and Cy. The first 6 patients received 16 mg/kg Bu and 200 mg/kg Cy. 3 died of transplant-related complications and 3 survived without thalassaemia 701-762 days after transplantation. The subsequent 24 patients received 14 mg/kg Bu and 200 mg/kg Cy. 1 died on day 28 without engraftment and 23 survived 64-624 days after transplantation. 19 of the 23 surviving patients are without thalassaemia while 4 patients with initial engraftment became thalassaemic again in 32-46 days and survived 253-624 days after transplantation. The latest death was 50 days after transplantation. The probability of developing grade 2 or greater acute graft versus host disease (GVHD) in patients with sustained engraftment was 23%. 5 patients had chronic GVHD which is still active and causing disability in 3 patients 358, 456, and 477 days after transplantation. The actuarial survival was 86% and the actuarial disease-free survival was 73%.

Actuarial Analysis↗