PubMed Health⌕ Search

Biomedical subjects

M Sardella

Publications and source records attributed to M Sardella.

At least 19 recordsLinked to original sources
PubMed2001

Carotid endarterectomy: a new technique replacing internal shunts.

BACKGROUND: Carotid endarterectomy has been reported to increase the time free from cerebral ischemic events in both symptomatic and asymptomatic patients with a high grade of stenosis of the internal carotid artery. In cases in whom the compensatory circulation during the carotid clamp time is not sufficient, the use of intraluminal shunts has been proposed. However, the use of intraluminal shunts present several problems, such as the technical difficulties in positioning the shunt, the variability of time requested for the placement, the inconstancy of the blood flow during surgery, and the need to clamp off the carotid to introduce and remove the shunt. For these reasons, most operators prefer not to employ intraluminal shunts, while others do use them only in selected cases. The purpose of this work is to present, for the first time, a new type of temporary extraluminal shunt, connecting the femoral to the internal carotid artery with the interposition of a roller pump to regulate the blood flow. This method allows one to perform carotid endarterectomy without interrupting the blood flow to the brain. METHODS: 407 consecutive patients, who underwent carotid endarterectomy between August 1992 and April 2000, were considered. 35 patients presented an absolutely insufficient collateral circulation, demonstrated by important modifications of the electroencephalographic monitoring during the carotid clamp time. In these patients the endarterectomy was performed using a new femoral-carotid extraluminal shunt. FINDINGS: In all the cases in whom the femoral-carotid extraluminal shunt was positioned, the normalisation of electroencephalographic monitoring was achieved by regulating the blood flow with the interposed roller pump. The use and the placement of the shunt was simple and easy. None of the patients showed postoperative complications, except for one who had a stroke two days after surgery. INTERPRETATION: The results obtained, although to be confirmed by further studies, seem to demonstrate the effectiveness of our femoral-carotid extraluminal shunt, which was simple to use and safe.

Aged↗
PubMed2001

Expression of KIF3C kinesin during neural development and in vitro neuronal differentiation.

KIF3A, KIF3B and KIF3C are kinesin-related motor subunits of the KIF3 family that associate to form the kinesin-II motor complex in which KIF3C and KIF3B are alternative partners of KIF3A. We have analysed the expression of Kif3 mRNAs during prenatal murine development. Kif3c transcripts are detectable from embryonic day 12.5 and persist throughout development both in the CNS and in some peripheral ganglia. Comparison of the expression patterns of the Kif3 genes revealed that Kif3c and Kif3a mRNAs colocalize in the CNS, while only Kif3a is also present outside the CNS. In contrast, Kif3b is detectable in several non-neural tissues. We have also performed immunocytochemical analyses of the developing rat brain and have found the presence of the KIF3C protein in selected brain regions and in several fibre systems. Using neuroblastoma cells as an in vitro model for neuronal differentiation, we found that retinoic acid stimulated the expression of the three Kif3 and the kinesin-associated protein genes, although with different time courses. The selective expression of Kif3c in the nervous system during embryonic development and its up-regulation during neuroblastoma differentiation suggest a role for this motor during maturation of neuronal cells.

Animals↗
PubMed1999

A computer-driven approach to PCR-based differential screening, alternative to differential display.

MOTIVATION: Polymerase chain reaction (PCR)-based RNA fingerprinting is a powerful tool for the isolation of differentially expressed genes in studies of neoplasia, differentiation or development. Arbitrarily primed RNA fingerprinting is capable of targeting coding regions of genes, as opposed to differential display techniques, which target 3' non-coding cDNA. In order to be of general use and to permit a systematic survey of differential gene expression, RNA fingerprinting has to be standardized and a number of highly efficient and selective arbitrary primers must be identified. RESULTS: We have applied a rational approach to generate a representative panel of high-efficiency oligonucleotides for RNA fingerprinting studies, which display marked affinity for coding portions of known genes and, as shown by preliminary results, of novel ones. The choice of oligonucleotides was driven by computer simulations of RNA fingerprinting reverse transcriptase (RT)-PCR experiments, performed on two custom-generated, non-redundant nucleotide databases, each containing the complete collection of deposited human or murine cDNAs. The simulation approach and experimental protocol proposed here permit the efficient isolation of coding cDNA fragments from differentially expressed genes. AVAILABILITY: Freely available on request from the authors. CONTACT: fesce.riccardo@hsr.it

Base Composition↗
PubMed1998

Changes in gene expression during the growth arrest of HepG2 hepatoma cells induced by reducing agents or TGFbeta1.

The growth of hepatoma cells can be inhibited by treatment with TGFbeta1 or with exogenous reducing agents. To gain information on the molecular mechanisms underlying growth arrest, we visualized and compared gene expression profiles of proliferating versus non proliferating HepG2 cells by computer-assisted gene fishing, an improved technique of RNA fingerprinting that allows the selective amplification of coding regions within transcripts. While many transcripts are selectively regulated by either treatment, a set of bands appear to be coordinately regulated by 2ME and TGFbeta1, suggesting their possible involvement in the mechanisms of growth arrest. Display tags corresponding to 18 differentially expressed genes were cloned and, in most cases, identified as known genes or, more frequently, as their homospecific/cross-specific homologues. A novel member of the kinesin superfamily was identified amongst the genes induced by both 2ME and TGFbeta1. This gene, KIF3C, is upregulated in several cell lines undergoing growth arrest. Taken together, our findings show that computer-assisted gene fishing is a powerful tool for the identification and cloning of genes involved in the control of cell proliferation and indicate that extracellular reducing agents can regulate cell growth through modulation of gene expression.

Carcinoma, Hepatocellular↗
PubMed1998

KIF3C, a novel member of the kinesin superfamily: sequence, expression, and mapping to human chromosome 2 at 2p23.

Kinesins are microtubule-dependent molecular motors involved in intracellular transport and mitosis. Here, we report the cloning, sequencing, mapping, and expression of a novel member of the kinesin superfamily. The sequence of this newly identified human cDNA reveals an open reading frame encoding a putative protein of 792 residues. Based on its high sequence similarity to the kinesin-like molecule KIF3B, we named this protein KIF3C. KIF3C is encoded by transcripts that are distinct from the KIF3B mRNA in human, rat, and mouse and is preferentially expressed in the brain. Fluorescence in situ hybridization reveals that, in the human genome, the KIF3C gene maps to chromosome 2 at 2p23. The sequence of KIF3C predicts an unusually long insertion in the proximity of L11, a region thought to mediate microtubule binding. Taken together, these findings suggest that KIF3C is a novel kinesin-like protein that might be specifically involved in microtubule-based transport in neuronal cells.

Amino Acid Sequence↗
PubMed1981

[The predictive value of serial scintigraphy and computerized tomography in the diagnosis of brain lesions (author's transl)].

Six characteristic initial clinical neurological patterns were defined and their incidence was determined in one year caselist of patients hospitalized in the Neurology Department of the General Hospital of Saronno. Since the predictive value of a diagnostic procedure depends not only on sensitivity and specificity but also on the prevalence of disease in the population sampled, the prevalence of surgical brain lesions was evaluated retrospectively in this caselist for each of the clinical patterns previously defined, in order to evaluate the predictive value of serial brain scintigraphy and of brain computerized tomography. In this caselist the most frequent clinical patterns (stroke, skull trauma) show a low prevalence of surgical lesions, unlike it happens in the Neurosurgery Department of another hospital chosen as reference. It follows that in the sample of population constituted by the patients hospitalized for "stroke" in the Neurology Department of this hospital the Bayes' theorem yields a predictive value of brain scintigraphy not significantly inferior in respect of computerized brain tomography. In addition a review of the positive scans of patients with cerebral infarction has shown the possibility of a correct diagnosis in 95%. Therefore the serial scintigraphy is thought to keep a high value as a screening tool in this kind of patients where, after a simple clinical selection, the prevalence of brain lesions needing of surgery is low.

Brain Injuries↗