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Biomedical subjects

G Di Bernardo

Publications and source records attributed to G Di Bernardo.

16 recordsLinked to original sources
PubMed2005

Ancient DNA as a multidisciplinary experience.

Investigation into DNA from archeological remains offers an inestimable tool for unraveling the history of humankind. However, a series of basic and technical difficulties renders the analysis of ancient DNA (aDNA) molecules troublesome, depending either on their own peculiar characteristics or on the complexity of processes affecting the bone matrix over time, all compromising the preservation of ancient DNA. This review underlines the contribution of many different disciplines, in particular molecular biology and genetics, to overcome these obstacles. The role of each expertise is illustrated to appropriately address the questions arising in aDNA investigations.

Animals↗
PubMed2004

Genetic characterization of Pompeii and Herculaneum Equidae buried by Vesuvius in 79 AD.

DNA extracted from the skeletons of five equids discovered in a Pompeii stable and of a horse found in Herculaneum was investigated. Amino acid racemization level was consistent with the presence of DNA. Post-mortem base modifications were excluded by sequencing a 146 bp fragment of the 16S rRNA mitochondrial gene. Sequencing of a 370 bp fragment of mitochondrial (mt)DNA control region allowed the construction of a phylogenetic tree that, along with sequencing of nuclear genes (epsilon globin, gamma interferon, and p53) fragments, gave us the possibility to address some questions puzzling archaeologists. What animals-donkeys, horses, or crossbreeds-were they? And, given they had been evidently assigned to one specific job, were they all akin or were they animals with different mitochondrial haplotypes? The conclusions provided by molecular analysis show that the Pompeii remains are those of horses and mules. Furthermore one of the equids (CAV5) seems to belong to a haplotype, which is either not yet documented in the GenBank or has since disappeared. As its characteristics closely recall those of donkeys, which is the out group chosen to construct the tree, that appears to have evolved within the Equidae family much earlier than horses, this assumption seems to be nearer the truth.

Animals↗
PubMed2001

pRb2/p130 gene overexpression induces astrocyte differentiation.

There are many data on the activity of the RB gene in neural differentiation and apoptosis, but the role of pRb2/p130 in neuronal and glial maturation has been far less investigated. To elucidate the role of pRb2/p130 in astrocyte development we overexpressed this protein in astrocytoma and normal astrocyte cultures by adenoviral-mediated gene transfer. In astrocytoma cells, p130/RB2 overexpression resulted in a significant reduction of cell growth and in an increased G(0)/G(1) cell population. We did not observe any induction of programmed cell death as determined by TUNEL reaction. Interestingly, pRb2/p130 overexpression induced astrocyte differentiation. Astrocyte cell cycle arrest and differentiation seemed to proceed through a way distinct from the p53 pathway.

Adenoviridae↗
PubMed2000

In vivo effects of partial phosphorothioated AT1 receptor antisense oligonucleotides in spontaneously hypertensive and normotensive rats.

Partial phosphorothioate (PS) antisense oligodeoxynucleotides (ODNs) targeted against rat AT1 receptor mRNA have been used to control blood pressure in normotensive (WKY) and spontaneously hypertensive (SHR) rats. Molecules were injected intracerebroventricularly (i.c.v., right lateral ventricle) in freely moving animals. The antisense ODN lowered the mean arterial pressure (MAP) 24 hours (-43 mmHg+/-10) and 48 hours (-30 mmHg+/-13) after injection, while the control ODN molecule had no significant effects. The observed decrease of blood pressure was due to a specific inhibition of AT1 receptor gene expression, since the level of its mRNA, monitored by reverse transcription (RT)- polymerase chain reaction (PCR), was significantly reduced by antisense molecule (-40%), compared to sense one. In normotensive rats no effect on MAP have been observed, while AT1 receptor gene expression is reduced (-40%) by antisense treatment. It is known that SHRs have an enhanced basal activity of the central renin-angiotensin system that induces an increase in central sympathetic outflow. Instead in WKY rats the central sympathetic outflow is not conditioned by the enhanced activity of brain renin-angiotensin system. Therefore in normotensive rats although partial PS ODN reduces the AT1 mRNA level this will not result in a modification of the sympathetic outflow and no change in MAP level would be observed.

Angiotensin Receptor Antagonists↗
PubMed2000

Detection of DNA in ancient bones using histochemical methods.

We describe histochemical techniques for detecting DNA within the osteocytic lacunae of ancient bones. The bones examined were fragments of femurs from two human individuals found in the Pompeian C. I. Polybius house and fragments of metacarpals from two horses (Equus sp.) found in the Pompeian "Casti Amanti" house. Both buildings were buried by the 79 A. D. Vesuvius eruption. Fragments of femurs from a modern horse, a modern swine and a modern amphibian also were studied as controls. Some bone sections were stained with two different DNA-specific fluorochromes, 4'-'6-diamidino-2-phenylindole (DAPI) and chromomycin A3 (CMA), while others were stained by the Feulgen reaction. All of the techniques gave a positive reaction within the osteocytic lacunae. Histological analysis of the undecalcified, ground and unstained sections agreed well with results of bone sections stained with either the fluorochromes or the Feulgen reaction. Bones showing good histology also were positive by our DNA-specific stain. Histochemical and histological analyses correlated well with the success of DNA extraction and amplification. Using conventional DNA-specific histochemical techniques in conjunction with histological analysis can be useful in the study of DNA extracted from ancient bone remains while reducing both the amount of time and cost.

Animals↗
PubMed1999

Induction of apoptosis and differentiation in neuroblastoma and astrocytoma cells by the overexpression of Bin1, a novel Myc interacting protein.

Bin1 is a novel protein that specifically binds Myc and inhibits, at least in part, Myc transactivation. Bin1 seems to play a role in cell cycle control, acting as a tumor suppressor gene. Since MYC family genes play a regulatory role in the proliferation, differentiation, and apoptosis of the nervous system, we studied the effects of the overexpression of the Myc-interacting protein, Bin1, in neuroblastoma and astrocytoma cell lines, which were chosen as neural cell system models. The major effects of BIN1 overexpression observed in undifferentiated neuroblastoma and astrocytoma cells were a significant reduction of cell growth, an increase in the G(0)/G(1) cell population and the induction of apoptosis. The trigger of programmed cell death by Bin1 is described for the first time. Bin1 overexpression in undifferentiated cells did not induce any maturation process as neither neuronal nor astrocyte differentiation markers were upregulated in neuroblastoma and astrocytoma cells, respectively. On the other side, the effects of Bin1 overproduction in neuroblastoma and astrocytoma cells committed towards neuronal and astrocyte differentiation, respectively, were different from those observed in undifferentiated cells. Although we did not evidence any triggering of programmed cell death, we did notice a further induction towards more differentiated phenotypes. Our studies suggest that Bin1 overexpression in neuroblastoma and astrocytoma cells can result in one of the following pathways: (1) suppressed cell proliferation, (2) induced differentiation, or (3) apoptosis. Thus, it appears that Bin1 operates through different pathways that involve activation of different genes: the chosen pathway however will depend on the proliferating or differentiated state of the cell.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Antisense inhibitory effect: a comparison between 3'-partial and full phosphorothioate antisense oligonucleotides.

Phosphorothioate (PS) antisense oligonucleotides are currently used to inhibit many cell functions both in vivo and in vitro. However, these modified oligos provide reasonable sequence specificity only within a narrow concentration range. To overcome such a limitation we synthesized antisense oligomers, partially phosphorothioated, targeted against the human N-myc mRNA. We utilized such modified oligomers in a human neuroblastoma cell line where the N-myc gene expression was very high, and compared them to full phosphorothioate oligonucleotides. Both full PS and partial PS antisense oligos produced a maximum reduction in target mRNA after 6 h of treatment. They were able to maintain a good level of inhibition for 20 h only at high concentration. While partial PS oligos produced a dose dependent and sequence specific inhibition of N-myc mRNA, full PS molecules suffer from some disadvantages at the highest concentration used. Our results showed that partial PS molecules were capable of reducing gene expression showing a greater sequence specificity over a far broader concentration range. For this reason we conclude that partial PS antisense oligos, with respect to full PS antisense oligos, might be particularly useful for studying gene function.

Base Sequence↗
PubMed1999

Differentiation and apoptosis of neuroblastoma cells: role of N-myc gene product.

To clarify the role and function of the N-myc product in cell differentiation and apoptosis, we used the antisense oligonucleotide technique to inhibit N-myc gene expression in neuroblastoma cells with different phenotypes: intermediate (I) and neuronal (N), or Schwann-glia (S), respectively. The results suggest that N-myc operates along different pathways. Inhibiting N-myc gene expression either results in suppression of cell proliferation or in induction of differentiation and/or apoptosis.

Apoptosis↗
PubMed1998

Ancient DNA in human bone remains from Pompeii archaeological site.

aDNA extraction and amplification procedures have been optimized for Pompeian human bone remains whose diagenesis has been determined by histological analysis. Single copy genes amplification (X and Y amelogenin loci and Y specific alphoid repeat sequences) have been performed and compared with anthropometric data on sexing.

Amelogenin↗
PubMed1998

Antisense oligonucleotides and myotonin gene expression in C2 mouse cells.

By describing the behavior of myotonin mRNA levels, from the quiescent to the differentiated state in C2 mouse myoblasts, we produced evidence bearing on the role of myotonin gene product in the control of cell growth and differentiation. To study the role of myotonin in myotonic dystrophy (DM) pathogenesis, we developed a suitable cellular model where myotonin gene expression was modulated by phosphorothioate antisense oligonucleotides in C2 cultured cells. Furthermore, an isoform of the gene product, similar to that described in humans and not yet described in the mouse, was found.

Animals↗
PubMed1997

CTG repeat number in the nonaffected allele of myotonic dystrophy patients is not critical for disease expression.

To investigate whether unusual allele segregation might explain the dominant negative effect of the expanded allele for myotonic dystrophy on myotonin protein kinase mRNA metabolism, which is suggested to cause the disease, we determined the number of CTG repeats at the DM locus in the nonaffected alleles of 64 DM (dystrophia myotonia) patients. The relative distribution was then compared with the distributions obtained from alleles of the normal parents and normal siblings of DM patients. Comparison was also made with the allele distribution of normal subjects from the same geographic area. It appears that the CTG repeat number of the nonaffected allele in DM patients is not critical for the expression of the disease.

Alleles↗
PubMed1996

Myotonic dystrophy: antisense oligonucleotide inhibition of DMPK gene expression in vitro.

Antisense phosphorothioate oligonucleotides, targeted against the first codon starting region of DMPK mRNA, were successfully used in K562 and HepG2 cells to decrease DMPK expression. The most effective antisense oligo, MIO1, when added to K562 cells, shows a 75% reduction of the DMPK gene expression 6 hours after addition. The same molecule, when encapsulated in liposomes, delays myotonin mRNA decrease at 24 hours after cell treatment. This considerable success with such inhibition in vitro could be utilised to generate a cell model to study myotonic dystrophy (DM) chemio-physiological alterations.

Base Sequence↗
PubMed1975

[The role of hypnosis in present-day obstetrics].

There is a present need for the insertion of psychology in teaching and medical practice so that full value and respect can be given to the patient's human side. Psychological assistance during pregnancy is reviewed and a brief account is given of early hypnotic techniques in the Soviet Union. Here, however, note is taken of the fact that attention was initially paid to symptoms alone and not their causes. As these techniques spread throughout Europe, they gradually lost touch with hypnosis and moved into the realm of teaching thus becoming completely ineffective. At present, more complete and more advanced hypnotic techniques are used. These throw particular light on the psychological causes of tension in pregnancy and are suitably backed up by instruction relating to the various problems encountered during gestation.

Adult↗
PubMedDate not supplied

Methods to improve the yield and quality of DNA from dried and processed figs.

We describe here a molecular method that can be used to detect genome traits of a given horticultural item at each stage from the farm to the market. We developed a procedure to extract and amplify by PCR DNA obtained from complex matrixes, such as dried figs and fig jam. Few fragmented DNA molecules can be recovered from food products. However, we were able to increase the yield of PCR reactions by successfully applying an enzymatic repair protocol to retrieved DNA.

Base Sequence↗