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Biomedical subjects

L Monaco

Publications and source records attributed to L Monaco.

At least 19 recordsLinked to original sources
PubMed2006

Saporin as a novel suicide gene in anticancer gene therapy.

We used a non-viral gene delivery approach to explore the potential of the plant saporin (SAP) gene as an alternative to the currently employed suicide genes in cancer therapy. Plasmids expressing cytosolic SAP were generated by placing the region encoding the mature plant ribosome-inactivating protein under the control of cytomegalovirus (CMV) or simian virus 40 (SV40) promoters. Their ability to inhibit protein synthesis was first tested in cultured tumor cells co-transfected with a luciferase reporter gene. In particular, SAP expression driven by CMV promoter (pCI-SAP) demonstrated that only 10 ng of plasmid per 1.6 x 10(4) B16 cells drastically reduced luciferase activity to 18% of that in control cells. Direct intratumoral injection of pCI-SAP complexed with either lipofectamine or N-(2,3-dioleoyloxy-1-propyl) trimethylammonium methyl sulfate (DOTAP) in B16 melanoma-bearing mice resulted in a noteworthy attenuation of tumor growth. This antitumor effect was increased in mice that received repeated intratumoral injections. A SAP catalytic inactive mutant (SAP-KQ) failed to exert any antitumor effect demonstrating that this was specifically owing to the SAP N-glycosidase activity. Our overall data strongly suggest that the gene encoding SAP, owing to its rapid and effective action and its independence from the proliferative state of target cells might become a suitable candidate suicide gene for oncologic applications.

Animals↗
PubMed2005

The effect of esophageal myotomy and myectomy on the lower esophageal sphincter pressure profile: intraoperative computerized manometry study.

SUMMARY: The surgical treatment of achalasia, based on Heller's myotomy is the procedure of choice to reduce the sphincterial high pressure zone, either by laparotomy or, most recently, by laparoscopy. What is the right length of the myotomy? Many authors have reported 10-15% postoperative residual dysphagia, due to the incomplete gastric myotomy and not to esophageal pouring. The aim of this study is to experimentally determine the modifications induced by Heller's myotomy and myectomy of the esophago-gastric junction on lower esophageal sphincter (LES) pressure profile, using a computerized manometric system. Myotomy of the esophageal portion of the LES (i.e. without dissection of the gastric fibers) has not modified the parameters considered, while the dissection of gastric fibers for at least 2-3 cm on the anterior gastric wall has created a significant modification of the LES pressure profile. Our observations seem to confirm and more clearly demonstrate the important role played by gastric fibers in sustaining the sphincteric HPZ. Moreover, analysis of our data, showed the need to always perform a complete myotomy. This was objectively shown during the intervention by means of intraoperative manometry, in order to significantly reduce the possibility of a dysphagic relapse, caused by inadequate treatment.

Animals↗
PubMed2005

Gastric cancer in the elderly patient.

The incidence of gastric cancer is increasing in elderly patients, unlike what it's being observed in the younger patients. The aim of this study is to evaluate the impact of the age on the resecability, resection type (R0-R1-2), morbidity, mortality and survival rate. The higher mortality observed in the elderly patients, the discussed role of an extended lymphadenectomy and the poor survival rate, would lead to a surgical approach which mostly tends to the palliation of the symptoms than the obtainment of a curative resection. But, on the other hand, the impossibility of making chemotherapy in most of the over 75 year old patients, lead us to a R0 surgery treatment.

Age Factors↗
PubMed2004

[Antithrombotic prophylaxis in day surgery: proposal of a clinical protocol].

The considerable diffusion of the day surgery has new problems such as the use of antithrombotic prophylaxis, now carried out systematically in major surgery. An the basis of the poor data present in the literature, a protocol of study is proposed to evaluate the real effectiveness of this type of prophylaxis in DS, dividing the patients into 3 groups, according to the patient's risk factors to the intervention and to the disease.

Ambulatory Surgical Procedures↗
PubMed2003

[Surgical treatment of esophageal achalasia by Heller+Nissen laparoscopic procedure. A 24-hour ambulatory esophageal manometry study].

BACKGROUND: The aim of this work was to evaluate, by means of a 24-h esophageal manometry, the motor activity of esophageal body in achalasic patients before and after Heller's myotomy and Nissen's fundoplication. METHODS: Twenty-five achalasic patients underwent a 24-h esophageal manometry. After surgical treatment they had a further 24-h esophageal manometry during follow-up. RESULTS: A statistically significant increase of amplitude of contraction and an increase, but not statistically significant, of frequency and duration of contractions were observed. The study of peristaltic activity showed an increase of peristaltic activity in total and complete sequences and decrease of dropped and interrupted peristaltic sequences. CONCLUSIONS: These data surprisingly showed the presence of a peristaltic activity (31.2%), in achalasic esophageal body, and complete sequences in 20%. The improvement of peristaltic activity observed after surgical abolition of the functional sphincteral rub, proposes again the question about the fall of the peristaltic activity of the esophageal body, which could be due to the hard transit through the LES. This preliminary data seem to confirm, in qualitative and quantitative manner, the positive effect of Heller's myotomy and the null effect of Nissen's fundoplication on the esophageal transit.

English Abstract↗
PubMed2001

Altered behavioral rhythms and clock gene expression in mice with a targeted mutation in the Period1 gene.

A group of specialized genes has been defined to govern the molecular mechanisms controlling the circadian clock in mammals. Their expression and the interactions among their products dictate circadian rhythmicity. Three genes homologous to Drosophila period exist in the mouse and are thought to be major players in the biological clock. Here we present the generation of mice in which the founding member of the family, Per1, has been inactivated by homologous recombination. These mice present rhythmicity in locomotor activity, but with a period almost 1 h shorter than wild-type littermates. Moreover, the expression of clock genes in peripheral tissues appears to be delayed in Per1 mutant animals. Importantly, light-induced phase shifting appears conserved. The oscillatory expression of clock genes and the induction of immediate-early genes in response to light in the master clock structure, the suprachiasmatic nucleus, are unaffected. Altogether, these data demonstrate that Per1 plays a distinct role within the Per family, as it may be involved predominantly in peripheral clocks and/or in the output pathways of the circadian clock.

Animals↗
PubMed2001

Biochemical characterization of bona fide polycystin-1 in vitro and in vivo.

The most common form of autosomal dominant polycystic kidney disease (PKD) results from mutation of the PKD1 gene on chromosome 16p13.3. The gene encodes a 14-kb messenger RNA that is predicted to express a 462-kd membrane protein. The gene product, polycystin-1, has a large extracellular portion composed of a novel combination of protein-protein interacting domains and is postulated to be a plasma membrane receptor involved in cell-cell/matrix interactions. However, slow progress has been made in the characterization of polycystin-1 or the determination of its function. In fact, the protein is expressed at very low levels in tissues and cell lines and previous efforts directed at expression of recombinant protein had been largely unsuccessful. We have recently developed constructs of full-length human PKD1 complementary (cDNA) that can be expressed in both a stable and transient fashion in mammalian cells. We used these systems to characterize our antibodies and to track the protein in vivo. We report here the first biochemical characterization of recombinant polycystin-1 and show that the protein is a 520-kd glycosylated polypeptide with an unglycosylated core of 460 kd. Subcellular fractionation as well as biotinylation studies confirmed that the protein is plasma-membrane associated. Furthermore, we show that the recombinant protein localizes to cell-cell junctions in polarized madin darby canine kidney cells as revealed by indirect immunofluorescence. Our data represent the first characterization of polycystin-1 performed under highly controlled conditions.

Animals↗
PubMed2000

A new Chinese hamster ovary cell line expressing alpha2,6-sialyltransferase used as universal host for the production of human-like sialylated recombinant glycoproteins.

Chinese hamster ovary (CHO) cells are widely employed to produce glycosylated recombinant proteins. Our group as well as others have demonstrated that the sialylation defect of CHO cells can be corrected by transfecting the alpha2,6-sialyltransferase (alpha2,6-ST) cDNA. Glycoproteins produced by such CHO cells display both alpha2,6- and alpha2,3-linked terminal sialic acid residues, similar to human glycoproteins. Here, we have established a CHO cell line stably expressing alpha2,6-ST, providing a universal host for further transfections of human genes. Several relevant parameters of the universal host cell line were studied, demonstrating that the alpha2,6-ST transgene was stably integrated into the CHO cell genome, that transgene expression was stable in the absence of selective pressure, that the recombinant sialyltransferase was correctly localized in the Golgi and, finally, that the bioreactor growth parameters of the universal host were comparable to those of the parental cell line. A second step consisted in the stable transfection into the universal host of cDNAs for human glycoproteins of therapeutic interest, i.e. interferon-gamma and the tissue inhibitor of metalloproteinases-1. Interferon-gamma purified from the universal host carried 40.4% alpha2,6- and 59.6% alpha2,3-sialic acid residues and showed improved pharmacokinetics in clearance studies when compared to interferon-gamma produced by normal CHO cells.

Animals↗
PubMed2000

Polycystin-1, the gene product of PKD1, induces resistance to apoptosis and spontaneous tubulogenesis in MDCK cells.

The major form of autosomal dominant polycystic kidney disease (ADPKD) results from mutation of a gene (PKD1) of unknown function that is essential for the later stages of renal tubular differentiation. In this report, we describe a novel cell culture system for studying how PKD1 regulates this process. We show that expression of human PKD1 in MDCK cells slows their growth and protects them from programmed cell death. MDCK cells expressing PKD1 also spontaneously form branching tubules while control cells form simple cysts. Increased cell proliferation and apoptosis have been implicated in the pathogenesis of cystic diseases. Our study suggests that PKD1 may function to regulate both pathways, allowing cells to enter a differentiation pathway that results in tubule formation.

Animals↗
PubMed2000

Glomerular filtration is required for transfection of proximal tubular cells in the rat kidney following injection of DNA complexes into the renal artery.

Gene transfer to the kidney can be achieved with various DNA vectors, resulting in transgene expression in glomerular or tubular districts. Controlling transgene destination is desirable for targeting defined renal cells for specific therapeutic purposes. We previously showed that injection of polyplexes into the rat renal artery resulted in transfection of proximal tubular cells. To investigate whether this process involves glomerular filtration of the DNA-containing particles, fluorescent polyethylenimine polyplexes were prepared, containing fluoresceinated poly-L-lysine. This allowed visualization of the route of the particles into the kidney. Our polyplexes were filtered through the glomerulus, since fluorescent proximal tubuli were observed. Conversely, fluorescent lipopolyplexes containing the cationic lipid DOTAP were never observed in tubular cells. Size measurements by laser light scattering showed that the mean diameter of polyplexes (93 nm) was smaller than that of lipopolyplexes (160 nm). The size of the transfecting particles is therefore a key parameter in this process, as expected by the constraints imposed by the glomerular filtration barrier. This information is relevant, in view of modulating the physico-chemical properties of DNA complexes for optimal transgene expression in tubular cells. Gene Therapy (2000) 7, 279-285.

Animals↗
PubMed2000

Project back-on-track at 1 year: a delinquency treatment program for early-career juvenile offenders.

OBJECTIVE: This study assessed the effectiveness of Project Back-on-Track, an after-school diversion program that uses a multimodal approach for the treatment of early-career juvenile offenders. METHOD: Project Back-on-Track completers (30 of 41 enrollees; 73%), aged 9 to 17 years, 63% female, participated in a 4-week cycle of treatment consisting of group and family therapies, parent groups, educational sessions, community service projects, and empathy-building exercises. These youths attended the program 2 hours per day, 4 days a week, allowing for 32 hours of contact with the program per cycle; parents attended the program for 15 hours per cycle. Most youths were referred for violent offenses and met criteria for conduct disorder. RESULTS: Project Back-on-Track completers were significantly less likely than matched controls to have committed subsequent criminal offenses at 12 months. In addition, they had significantly fewer subsequent criminal charges at 9- and 12-month follow-up intervals than the control group. By decreasing the frequency of criminal recidivism, it is estimated that Project Back-on-Track resulted in savings to society of approximately $1,800 per youth enrolled after 1 year. CONCLUSION: At 1-year follow-up, findings suggest that treatment through Project Back-on-Track was effective in reducing criminal recidivism and costs in a population of early-career juvenile offenders.

Adolescent↗
PubMed2000

Anger experience, styles of anger expression, sadistic personality disorder, and psychopathy in juvenile sexual homicide offenders.

Sexual homicide by juveniles is a rare phenomenon, and information regarding the psychological and behavioral characteristics of this group is limited. No studies exist which have investigated anger experience and styles of anger expression, and the relationship between anger, sadistic personality disorder, and psychopathy, in this type of youthful offender. These areas were explored by evaluating 14 juvenile sexual homicide offenders through clinical assessment, the State-Trait Anger Expression Inventory (STAXI), the Schedule for Nonadaptive and Adaptive Personality (SNAP), the Revised Psychopathy Checklist (PCL-R), and review of correctional records. Descriptive information for the STAXI scales and internal consistency data are presented. Trait Anger was significantly higher than State Anger for the youth, but still comparable to adolescent norms. The difference between Anger-In and Anger-Out scale scores was not significant. Unexpectedly, Anger Control scale scores were significantly higher than Anger Out scale scores, clinically consistent with efforts by some of these boys to resist sadistic impulses. Those four (31%) participants who met criteria for sadistic personality had significantly higher Anger-Out scale scores than those without the disorder, and were also higher on Trait Anger to a marginally significant degree. Psychopathy was significantly negatively associated with Anger Control. This study is intended to contribute to the scant literature on juvenile sexual homicide, and lends some support to the validity and utility of sadistic personality disorder as a diagnosis in younger forensic populations. The findings did not support the contention that this form of violence is necessarily an outgrowth of excessive anger.

Adolescent↗
PubMed1999

Requirement of Rsk-2 for epidermal growth factor-activated phosphorylation of histone H3.

During the immediate-early response of mammalian cells to mitogens, histone H3 is rapidly and transiently phosphorylated by one or more unidentified kinases. Rsk-2, a member of the pp90rsk family of kinases implicated in growth control, was required for epidermal growth factor (EGF)-stimulated phosphorylation of H3. RSK-2 mutations in humans are linked to Coffin-Lowry syndrome (CLS). Fibroblasts derived from a CLS patient failed to exhibit EGF-stimulated phosphorylation of H3, although H3 was phosphorylated during mitosis. Introduction of the wild-type RSK-2 gene restored EGF-stimulated phosphorylation of H3 in CLS cells. In addition, disruption of the RSK-2 gene by homologous recombination in murine embryonic stem cells abolished EGF-stimulated phosphorylation of H3. H3 appears to be a direct or indirect target of Rsk-2, suggesting that chromatin remodeling might contribute to mitogen-activated protein kinase-regulated gene expression.

3T3 Cells↗
PubMed1998

Impairing follicle-stimulating hormone (FSH) signaling in vivo: targeted disruption of the FSH receptor leads to aberrant gametogenesis and hormonal imbalance.

Pituitary gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone stimulate the gonads by regulating germ cell proliferation and differentiation. FSH receptors (FSH-Rs) are localized to testicular Sertoli cells and ovarian granulosa cells and are coupled to activation of the adenylyl cyclase and other signaling pathways. Activation of FSH-Rs is considered essential for folliculogenesis in the female and spermatogenesis in the male. We have generated mice lacking FSH-R by homologous recombination. FSH-R-deficient males are fertile but display small testes and partial spermatogenic failure. Thus, although FSH signaling is not essential for initiating spermatogenesis, it appears to be required for adequate viability and motility of the sperms. FSH-R-deficient females display thin uteri and small ovaries and are sterile because of a block in folliculogenesis before antral follicle formation. Although the expression of marker genes is only moderately altered in FSH-R -/- mice, drastic sex-specific changes are observed in the levels of various hormones. The anterior lobe of the pituitary gland in females is enlarged and reveals a larger number of FSH- and thyroid-stimulating hormone (TSH)-positive cells. The phenotype of FSH-R -/- mice is reminiscent of human hypergonadotropic ovarian dysgenesis and infertility.

Animals↗
PubMed1998

Diagnosis and treatment of an adolescent with comorbid type 1 diabetes mellitus and anorexia nervosa.

The authors describe the successful treatment of a 17-year-old female with comorbid type 1 diabetes mellitus and anorexia nervosa within the context of a residential program in a tertiary care facility. Assessment and treatment of the complex combinations of the psychological and medical symptoms involved in this patient required the interaction of medical, psychological, and nutritional services. Diagnostic and treatment challenges are discussed.

Adolescent↗
PubMed1997

Cross-talk in signal transduction: Ras-dependent induction of cAMP-responsive transcriptional repressor ICER by nerve growth factor.

The CREM gene encodes both activators and repressors of cAMP-induced transcription. By virtue of an alternative, intronic promoter within the gene, the ICER (Inducible cAMP Early Repressor) isoform is generated. ICER acts as a dominant negative regulator and is cAMP-inducible in various neuroendocrine cells and tissues. ICER negatively autoregulates its own expression, and appears to participate in the molecular events governing oscillatory hormonal regulations. Here we report that ICER is inducible with nerve growth factor (NGF). This is the first example of cAMP-independent induction of ICER expression. Importantly, induction by NGF occurs via a subset of the CREs present in the ICER promoter which were previously shown to direct cAMP-inducibility. ICER induction correlates with a NGF-mediated phosphorylation of CREB. Both CREB phosphorylation and ICER inducibility require an intact Ras-dependent signalling pathway. We show that increased ICER levels result in the attenuation of c-fos expression. The activation of a powerful repressor of cAMP-responsive transcription by NGF, whose transduction signalling is cAMP-independent, constitutes a notable example of nuclear cross-talk and thus is likely to have relevant physiological implications.

Animals↗