Biomedical subjects
Publications and source records attributed to L Invernizzi.
We present the genotyping of apolipoprotein (apo) E by means of restriction fragment analysis of amplified genomic DNA by high-performance capillary electrophoresis and a replaceable non-gel-sieving matrix. This procedure streamlines the genotyping of apo E in large-scale population studies because of the automation and speed of capillary electrophoresis.
The applicability of automated DNA sequencing systems to sequencing strategies that require a large number of primers is limited by the necessity for expensive fluorescence-labeled oligonucleotides. Here we present a simple procedure that allows the use of unlabeled oligonucleotides to perform fluorescence-based DNA sequencing. This method is based on a limited primer extension that incorporates three deoxynucleotides, one of which carries a fluorescent moiety. The elongated fluorescent primer is then used in a standard T7 sequencing reaction. This labeling procedure is both economical and straightforward and offers a valid alternative to current fluorescence-labeling protocols. Results of this method with different DNA templates demonstrate the reliability of the protocol.
Biotinylated oligonucleotides combined with streptavidin-coated magnetic beads are commonly used in current molecular biology. Their quality and the level of incorporated biotin are essential for yielding good results in either solid-phase DNA sequencing or solid-phase purification procedures. This paper presents a very simple analytical test using anion-exchange HPLC and avidin to ascertain the quality of biotinylated oligonucleotides and to predetermine their ability to bind to avidin, which is a prerequisite for functionality in some solid-phase methods.
Fluorescence-based, automated DNA sequences represent one of the major advances in recent molecular biology. Two main technologies have been developed in this field: the single-label/four-lane system and the four-label/one-lane system. The following present the use of single-label-sequencing chemistry, which resembles traditional radioactive DNA sequencing, using the four-label system ABI 373A that expands its flexibility and obtains data that are immediately interpretable without software manipulation. This method has been named mixed-mode fluorescent DNA sequencing. Here we show one of its possible applications in molecular genetic analysis.
Basement membranes are frequently absent in small-cell lung cancer (SCLC). To study this phenomenon, the production of laminin by SCLC cells, both in vitro and in vivo, has been investigated and compared with the laminin production by lung carcinomas of other histotypes (non-SCLC, NSCLC). Immunoradiometric and immunoperoxidase tests, respectively, carried out on culture supernatants and cells using antilaminin rabbit antiserum, revealed that in 1 (H446) out of 8 SCLC cell lines tested and in the NSCLC line Calu3, laminin was detectable both in the culture medium and in the cytoplasm of the cells. After treatment of an SCLC-negative cell line (N592) with monensin, a molecule which inhibits protein secretion, laminin became detectable in the cytoplasm. Similar results were obtained by FACS analysis on cells permeabilized with saponin. Northern analysis indicated that the laminin B1 gene was transcribed. The level of mRNA for the B1 laminin subunit in the N592 cells was twice and 4 times higher than that found in the laminin-secreting Calu3 and H446 cell lines. The production of laminin in SCLC and NSCLC surgically resected samples using immunoperoxidase staining of cryostatic sections was also investigated. The results indicate that 85% of the NSCLC cases tested showed diffuse staining in the cytoplasm of the tumor cells and strong staining at the basement membrane level, whereas a similar staining was only found in 15% of the SCLC cases tested. The treatment of SCLC cells with differentiating agents in vitro has been shown to induce the adhesion of these cells. In fact, n-butyric acid induced the disaggregation of floating-clump cells and single-cell adhesion in the N592 line, whereas after treatment with retinoids the clumps of the N592 cells were still present, but 30% of these were found to adhere to the plate. However, no increase in the laminin production was found in the cytoplasmic or culture medium under these conditions.
In this communication we present the results obtained by the use of magnetic beads in diagnosis, for the identification of genetic variants at the molecular level by sequencing, in comparison with the more laborious method of the production of ssDNA with asymmetric PCR. We compared the two techniques studying variants of beta globin gene: Hb Abruzzo [beta 143 (H21) His -> Arg] and Hb D Los Angeles [beta 121 (GH4) Glu -> Gln].
The mucosal pathological lesions of oral cavity in literature are reviewed and the Authors report about etiopathogenesis, development and clinic of herpetic infection, oral candidosis, lichen and white spongious naevus. They discuss the utility of a combined clinic among stomatologist, internist and dermatologist in order to have a satisfactory treatment of the diagnosed illness.
The drugs and drug combinations responsible for cutaneo-mucosae reactions are extremely numerous and only the most frequently responsible are mentioned. Pathogenic processes are described: immune-allergic, overdosing, idiosynerasy, drug interactions, etc... Alterations provoked are various and vary from erythema up to acute skin necrosis. We would suggest caution, in prescribing drugs and drug combinations.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.