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1.
Hum Reprod ; 36(5): 1367-1375, 2021 04 20.
Article in English | MEDLINE | ID: mdl-33686407

ABSTRACT

STUDY QUESTION: Has the practice of individualizing the recombinant-FSH starting dose been superseded after the largest randomized controlled trial (RCT) in assisted reproduction technology (ART), the OPTIMIST trial? SUMMARY ANSWER: The OPTIMIST trial has influenced our ART daily practice to a limited degree, but adherence is still generally poor. WHAT IS KNOWN ALREADY: Although the 'one size fits all' approach has been discouraged for decades by most authors, the OPTIMIST study group demonstrated in a large prospective RCT that, in general, dosage individualization does not improve the prospects for live birth, although it may decrease ovarian hyperstimulation syndrome (OHSS) risk in expected high responders. STUDY DESIGN, SIZE, DURATION: Retrospective analysis of all first in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles from 1st January 2017 to 31st December 2018, before and after the OPTIMIST publication on November 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two thousand six hundred and seventy-seven patients, between 18 and 42 years old, undergoing their first IVF-ICSI cycle in seven Italian fertility centres, were included. Patients were allocated to three groups according to their ovarian reserve markers: predicted poor ovarian responders (POR), predicted normo-responders (NR) and expected hyper-responders (HRs). MAIN RESULTS AND THE ROLE OF CHANCE: Between 2017 and 2018, there was an overall increase in prescription of the standard 150 IU dose proposed by the OPTIMIST trial and a reduction in the use of a starting dose >300 IU. After subgroup analysis, the decrease in doses >300 IU remained significant in the POR and NR sub-groups. LIMITATIONS, REASONS FOR CAUTION: The retrospective nature of the study. Physicians need time to adapt to new scientific evidence and a comparison between 2017 and 2019 may have found a greater impact of the Optimist trial, although other changes over the longer time span might have increased confounding. We cannot be sure that the observed changes can be attributed to knowledge of the OPTIMIST trial. WIDER IMPLICATIONS OF THE FINDINGS: Clinicians may be slow to adopt recommendations based on RCTs; more attention should be given to how these are disseminated and promoted. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. E.P. reports grants and personal fees from MSD, grants from Ferring, from IBSA, grants and personal fees from Merck, grants from TEVA, grants from Gedeon Richter, outside the submitted work. E.S. reports grants from Ferring, grants and personal fees from Merck-Serono, grants and personal fees from Theramex, outside the submitted work. All other authors do not have conflicts of interest to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Subject(s)
Ovarian Hyperstimulation Syndrome , Sperm Injections, Intracytoplasmic , Adolescent , Adult , Birth Rate , Female , Fertilization in Vitro , Humans , Live Birth , Ovarian Hyperstimulation Syndrome/prevention & control , Ovulation Induction , Pregnancy , Young Adult
2.
Mar Pollut Bull ; 161(Pt A): 111738, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33065396

ABSTRACT

Over the past fifty years, interactions between anthropogenic debris and a wide range of marine species have increased. In cetaceans, the most frequent interactions have occurred through ingestion and/or entanglement, with results ranging from minor injuries to death in affected animals. While debris ingestion is widely documented in odontocetes, records are scarcer in mysticetes. This study describes the finding of plastic litter in the digestive tract of a southern right whale (Eubalaena australis) juvenile male, which was found dead on the shores of Golfo Nuevo, Chubut, Argentina in 2014. During the examination of intestinal contents, anthropogenic waste was found and classified as macro-debris (25 mm-1 m). Although this whale likely died of causes not related to this finding, it is the first record of anthropogenic debris ingestion for this species. This event adds information about the potential impact of human-made debris on a variety of aquatic species and ecosystems.


Subject(s)
Ecosystem , Whales , Animals , Argentina , Gastrointestinal Tract , Male , Plastics
3.
Sci Total Environ ; 650(Pt 1): 1521-1528, 2019 Feb 10.
Article in English | MEDLINE | ID: mdl-30308837

ABSTRACT

Persistent organic pollutants (POPs) were assessed for the first time in blue whales from the South Pacific Ocean. Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB) and dichlorodiphenyltrichloroethane and its main metabolites (DDTs), were determined in 40 blubber samples from 36 free-ranging individuals and one stranded, dead animal along the coast of southern Chile between 2011 and 2013. PCBs were the most abundant pollutants (2.97-975 ng/g l.w.), followed by DDTs (3.50-537 ng/g l.w.), HCB (nd-77.5 ng/g l.w.) and PBDEs (nd-33.4 ng/g l.w). There was evidence of differences between sexes, with lower loads in females potentially due to pollutants passing to calves. POP concentrations were higher in specimens sampled in 2013; yet, between-year differences were only statistically significant for HCB and PBDEs. Lower chlorinated (penta > tetra > tri) and brominated (tetra > tri) congeners were the most prevalent among PCBs and PBDEs, respectively, mostly in agreement with findings previously reported in blue and other baleen whales. The present study provides evidence of lower levels of contamination by POPs in eastern South Pacific blue whales in comparison to those reported for the Northern Hemisphere.


Subject(s)
Adipose Tissue/metabolism , Balaenoptera/metabolism , Environmental Monitoring , Water Pollutants, Chemical/metabolism , Animals , Chile , DDT/metabolism , Female , Halogenated Diphenyl Ethers/metabolism , Hexachlorobenzene/metabolism , Hydrocarbons, Chlorinated/metabolism , Male , Pacific Ocean , Polychlorinated Biphenyls/metabolism
5.
Biochim Biophys Acta ; 1862(6): 1182-90, 2016 06.
Article in English | MEDLINE | ID: mdl-26976330

ABSTRACT

AIM: The long pentraxin PTX3 plays a non-redundant role during acute myocardial infarction, atherosclerosis and in the orchestration of tissue repair and remodeling during vascular injury, clotting and fibrin deposition. The aim of this work is to investigate the molecular mechanisms underlying the protective role of PTX3 during arterial thrombosis. METHODS AND RESULTS: PTX3 KO mice transplanted with bone marrow from WT or PTX3 KO mice presented a significant reduction in carotid artery blood flow following FeCl3 induced arterial thrombosis (-80.36±11.5% and -95.53±4.46%), while in WT mice transplanted with bone marrow from either WT or PTX3 KO mice, the reduction was less dramatic (-45.55±1.37% and -53.39±9.8%), thus pointing to a protective effect independent of a hematopoietic cell's derived PTX3. By using P-selectin/PTX3 double KO mice, we further excluded a role for P-selectin, a target of PTX3 released by neutrophils, in vascular protection played by PTX3. In agreement with a minor role for hematopoietic cell-derived PTX3, platelet activation (assessed by flow cytometric expression of markers of platelet activation) was similar in PTX3 KO and WT mice as were haemostatic properties. Histological analysis indicated that PTX3 localizes within the thrombus and the vessel wall, and specific experiments with the N-terminal and the C-terminal PTX3 domain showed the ability of PTX3 to selectively dampen either fibrinogen or collagen induced platelet adhesion and aggregation. CONCLUSION: PTX3 interacts with fibrinogen and collagen and, by dampening their pro-thrombotic effects, plays a protective role during arterial thrombosis.


Subject(s)
C-Reactive Protein/metabolism , Collagen/metabolism , Fibrinogen/metabolism , Platelet Aggregation , Protein Interaction Maps , Serum Amyloid P-Component/metabolism , Thrombosis/metabolism , Animals , Blood Platelets/metabolism , Blood Platelets/pathology , Hemostasis , Mice , Mice, Inbred C57BL , P-Selectin/metabolism , Thrombosis/blood , Thrombosis/pathology
6.
Mol Biosyst ; 11(8): 2152-7, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26118819

ABSTRACT

In recent years the Ebola virus has spread through several countries in Africa, highlighting the need to develop new treatments for this disease and boosting a new research effort on this subject. The Ebola virus Viral Protein 35 (VP35) carries out multiple functions necessary for virus replication and infection, in particular interfering with (IFN)-α/ß signaling. Recently, VP35 has been crystallized in complex with small organic molecules able to inhibit its interaction with viral nucleoproteins, thus reducing Ebola infections of cultured cells. In this work, starting from these structures, we carry out a computational study aimed at investigating the energetic and dynamical aspects of the interaction between VP35 and its ligands at the atomic level. Molecular dynamics simulations, computational alanine scanning, root mean square fluctuations bootstrap analysis and essential dynamics analysis were performed. Our results expand the experimental ones obtained in previous works, adding information about the interactions landscape with the identification of a set of new hot-spots residues exerting a critical function in the protein-ligand interaction. Moreover we characterized the dynamics of the complexes, showing that the presence of ligands modifies the overall protein dynamics as well as the behavior of particular protein segments.


Subject(s)
Ebolavirus/chemistry , Hemorrhagic Fever, Ebola/virology , Viral Regulatory and Accessory Proteins/chemistry , Alanine , Cell Line , Computer Simulation , Ebolavirus/genetics , Ebolavirus/pathogenicity , Hemorrhagic Fever, Ebola/genetics , Humans , Ligands , Molecular Dynamics Simulation , Viral Regulatory and Accessory Proteins/metabolism , Virus Replication/genetics
7.
Pharmacol Res ; 81: 83-90, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24630950

ABSTRACT

CHF5074 is a non-steroidal anti-inflammatory derivative holding disease-modifying potential for the treatment of Alzheimer's disease. The aim of the present study was to characterize the electrophysiological and metabolic profile of CHF5074 in the hippocampus. Electrophysiological recordings show that CHF5074 inhibits in a dose-dependent manner the current-evoked repetitive firing discharge in CA1 pyramidal neurons. This result is paralleled by a dose-dependent reduction of field excitatory post-synaptic potentials with no effect on the paired-pulse ratio. The effects of CHF5074 were not mediated by AMPA or NMDA receptors, since the inward currents induced by local applications of AMPA and NMDA remained constant in the presence of this compound. We also suggest a possible activity of CHF5074 on ASIC1a receptor since ASIC1a-mediated current, evoked by application of a pH 5.5 solution, is reduced by pretreatment with this compound. Moreover, we demonstrate that CHF5074 treatment is able to counteract in hippocampal slices the OGD-induced increase in alanine, lactate and acetate levels. Finally, CHF5074 significantly reduced the apoptosis in hippocampal neurons exposed to OGD, as revealed by cleaved-caspase-3 immunoreactivity and TUNEL staining. Overall, the present work identifies novel mechanisms for CHF5074 in reducing metabolic acidosis, rendering this compound potentially useful also in conditions of brain ischemia.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cyclopropanes/pharmacology , Flurbiprofen/analogs & derivatives , Hippocampus/drug effects , Ischemia/drug therapy , Neuroprotective Agents/pharmacology , Acetates/metabolism , Alanine/metabolism , Animals , Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Cells, Cultured , Electrophysiological Phenomena , Flurbiprofen/pharmacology , Hippocampus/blood supply , Hippocampus/physiology , In Vitro Techniques , Ischemia/physiopathology , Lactic Acid/metabolism , Male , Mice, Inbred C57BL , Neurons/drug effects , Neurons/metabolism , Rats, Wistar
8.
J Prev Med Hyg ; 53(1): 37-43, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22803318

ABSTRACT

UNLABELLED: INTRODUCTION. The screening programmes are very challenging from the ethical perspective, and their impact in terms of morbidity and mortality make secondary colorectal cancer prevention a valuable public health intervention. METHODS: The target population people aged 50-69 years receive an invitation card with a test-tube for the fecal occult blood test (FOBT) and an immunochemical test is used for fecal occult blood. Subjects positive to FOBT are invited to perform a gastroenterologic examination and a full colonoscopy. RESULTS: In the firt round of screening, 100% of the target population has been invited with an adhesion rate of 41.3%. A total of 1739 FOBT-positive subjects have been invited to the second level of the screening. 1429 of them have performed the gastroenterologic examination (83.9%). To date 956 full colonoscopies have been completed and the rate of subjects affected by carcinoma, malignant polyp and advanced adenoma has been equal to 23.5%. DISCUSSION: Thanks to the reminders already sent, an increasing compliance has been registered with an increased rate of subjects with a low schooling that have performed a FOBT test. With the aim to optimize all the operative aspects of the screening programme it is already ongoing a set of meetings between health workers of Local Health Unit 4 and General Practioners.


Subject(s)
Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/prevention & control , Mass Screening/methods , Occult Blood , Patient Acceptance of Health Care/statistics & numerical data , Adenomatous Polyps/diagnosis , Adenomatous Polyps/prevention & control , Aged , Catchment Area, Health , Colonoscopy/statistics & numerical data , Colorectal Neoplasms/epidemiology , Female , Humans , Incidence , Indicators and Reagents , Italy/epidemiology , Male , Middle Aged , National Health Programs/organization & administration , Outcome Assessment, Health Care , Patient Compliance , Prevalence , Reagent Kits, Diagnostic , Sigmoidoscopy/statistics & numerical data
9.
Heredity (Edinb) ; 109(2): 117-26, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22549518

ABSTRACT

Molecules involved in leukocyte trafficking have a central role in the development of inflammatory and immune responses. We performed F(ST) analysis of the selectin cluster, as well as of SELPLG, ICAM1 and VCAM1. Peaks of significantly high population genetic differentiation were restricted to two regions in SELP and one in SELPLG. Resequencing data indicated that the region covering SELP exons 11-13 displays high nucleotide diversity in Africans and Europeans (CEU), and a high level of within-species diversity compared with inter-specific divergence. Analysis of inferred haplotypes revealed a complex phylogeny with two deeply separated clades that coalesce at ~3.5 million years (MY) plus a minor clade with a TMRCA (time to the most recent common ancestor) of ~2.2 MY. A splicing assay indicated no haplotype-specific effect on SELP exon 14 inclusion. These data are consistent with a model of multiallelic balancing selection; single-nucleotide polymorphism analysis indicated that the Val640Leu variant represents a likely selection target. In populations of Asian ancestry a distinct haplotype, possibly carrying regulatory variants, has been driven to high frequency by positive selection. No deviation from neutrality was observed for the SELPLG region. Resequencing of SELP in chimpanzees revealed a haplotype phylogeny with extremely deep basal branches, suggesting either long-standing balancing selection or ancestral population structure. Thus, SELP has experienced a complex selective history, possibly as a result of local adaptation. Variants in the gene have been associated with autoimmune and cardiovascular diseases. Association studies would benefit from both taking the complex SELP haplotype structure into account and from analysis of possible regulatory variants in the gene.


Subject(s)
Evolution, Molecular , Genetics, Medical , Multigene Family , Racial Groups/genetics , Selectins/genetics , Animals , Exons , Genetic Variation , Genetics, Population , Haplotypes , Humans , Pan troglodytes/classification , Pan troglodytes/genetics , Phylogeny , Polymorphism, Single Nucleotide
10.
Mol Biol Evol ; 29(6): 1599-613, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22319148

ABSTRACT

The human ZC3HAV1 gene encodes an antiviral protein. The longest splicing isoform of ZC3HAV1 contains a C-terminal PARP-like domain, which has evolved under positive selection in primates. We analyzed the evolutionary history of this same domain in humans and in Pan troglodytes. We identified two variants that segregate in both humans and chimpanzees; one of them (rs3735007) does not occur at a hypermutable site and accounts for a nonsynonymous substitution (Thr851Ile). The probability that the two trans-specific polymorphisms have occurred independently in the two lineages was estimated to be low (P = 0.0054), suggesting that at least one of them has arisen before speciation and has been maintained by selection. Population genetic analyses in humans indicated that the region surrounding the shared variants displays strong evidences of long-standing balancing selection. Selection signatures were also observed in a chimpanzee population sample. Inspection of 1000 Genomes data confirmed these findings but indicated that search for selection signatures using low-coverage whole-genome data may need masking of repetitive sequences. A case-control study of more than 1,000 individuals from mainland Italy indicated that the Thr851Ile SNP is significantly associated with susceptibility to multiple sclerosis (MS) (odds ratio [OR] = 1.47, 95% confidence intervals [CI]: 1.08-1.99, P = 0.011). This finding was confirmed in a larger sample of 4,416 Sardinians cases/controls (OR = 1.18, 95% CI: 1.037-1.344, P = 0.011), but not in a population from Belgium. We provide one of the first instances of human/chimpanzee trans-specific coding variant located outside the major histocompatibility complex region. The selective pressure is likely to be virus driven; in modern populations, this variant associates with susceptibility to MS, possibly via the interaction with environmental factors.


Subject(s)
Genetic Predisposition to Disease , Multiple Sclerosis/genetics , Polymorphism, Single Nucleotide , RNA-Binding Proteins/genetics , Selection, Genetic , Acebutolol , Animals , Case-Control Studies , Gene-Environment Interaction , Genetic Association Studies , Genome, Human , Haplotypes , Humans , Linkage Disequilibrium , Models, Genetic , Odds Ratio , Pan troglodytes/genetics , Phylogeny , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Structure, Tertiary , RNA-Binding Proteins/chemistry , Sequence Analysis, DNA
11.
J Chem Theory Comput ; 7(11): 3846-52, 2011 Nov 08.
Article in English | MEDLINE | ID: mdl-26598273

ABSTRACT

Osmolytes are small organic compounds that confer to the cell an enhanced adaptability to external conditions. Many osmolytes not only protect the cell from osmotic stress but also stabilize the native structure of proteins. While simplified models able to predict changes to protein stability are available, a general physicochemical explanation of the underlying microscopic mechanism is still missing. Here, we address this issue by performing very long all-atom MD simulations, free energy calculations, and experiments on a well-characterized mini-protein, the villin headpiece. Comparisons between the folding free energy landscapes in pure water and osmolyte solutions, together with experimental validation by means of circular dichroism, unfolding experiments, and NMR, led us to formulate a simple hypothesis for the protecting mechanism. Taken together, our results support a novel mechanistic explanation according to which the main driving force behind native state protection is a change in the solvent rotational diffusion.

12.
Genes Immun ; 10(8): 678-86, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19675583

ABSTRACT

Familial Mediterranean Fever (FMF) is a recessively inherited systemic autoinflammatory disease caused by mutations in the MEFV gene. The frequency of different disease alleles is extremely high in multiple populations from the Mediterranean region, suggesting heterozygote advantage. Here, we characterize the sequence variation and haplotype structure of the MEFV 3' gene region (from exon 5 to the 3' UTR) in seven human populations. In non-African populations, we observed high levels of nucleotide variation, an excess of intermediate-frequency alleles, reduced population differentiation and a genealogy with two common haplotypes separated by deep branches. These features are suggestive of balancing selection having acted on this region to maintain one or more selected alleles. In line with this finding, an excess of heterozygotes was observed in Europeans and Asians, suggesting an overdominance regime. Our data, together with the earlier demonstration that the MEFV exon 10 has been subjected to episodic positive selection over primate evolution, provide evidence for an adaptive role of nucleotide variation in this gene region. Our data suggest that further studies aimed at clarifying the role of MEFV variants might benefit from the integration of molecular evolutionary and functional analyses.


Subject(s)
Cytoskeletal Proteins/genetics , Familial Mediterranean Fever/genetics , Selection, Genetic , 3' Untranslated Regions , Animals , Cytoskeletal Proteins/immunology , Exons , Familial Mediterranean Fever/immunology , Genetics, Population , Haplotypes , Humans , Pan troglodytes/genetics , Pyrin
13.
J Med Genet ; 46(5): 345-51, 2009 May.
Article in English | MEDLINE | ID: mdl-19196735

ABSTRACT

BACKGROUND: Hereditary spastic paraplegia (HSP) with thin corpus callosum (HSP-TCC) is a frequent subtype of complicated HSP clinically characterised by slowly progressive spastic paraparesis with cognitive impairment and thin corpus callosum (TCC). SPG11, the gene associated with the major locus involved, encodes spatacsin, a protein of unknown function. METHODS: Different types of mutations were identified in patients with the complex form of HSP (cHSP) including TCC. We screened a series of 45 index patients with different types of cHSP with (n = 10) and without (n = 35) TCC. RESULTS: Ten mutations, of which five are novel, were detected in seven patients. Of importance, three out of seven mutated patients present with cHSP without TCC. Among the novel mutations identified, we characterised a large intragenic rearrangement deleting 2.6 kb of the SPG11 gene. The rearrangement is due to non-allelic homologous recombination between Alu sequences flanking the breakpoints. CONCLUSIONS: These findings expand the mutation spectrum of SPG11 and suggest that SPG11 mutations may occur more frequently in familial than sporadic forms of cHSP without TCC. This helps to define further clinical and molecular criteria for a correct diagnosis of the SPG11 related form of cHSP. In addition, the intragenic deletion detected here, and the mechanism involved, both provide clues to address the issue of SPG11 missing mutant alleles previously reported.


Subject(s)
Agenesis of Corpus Callosum , Point Mutation , Proteins/genetics , Sequence Deletion , Spastic Paraplegia, Hereditary/genetics , Amino Acid Sequence , Base Sequence , DNA Mutational Analysis/methods , DNA, Intergenic/genetics , Family Health , Female , Gene Frequency , Humans , Male , Molecular Sequence Data , Pedigree , Sequence Homology, Amino Acid , Spastic Paraplegia, Hereditary/pathology
14.
Plant Physiol Biochem ; 44(11-12): 893-900, 2006.
Article in English | MEDLINE | ID: mdl-17097297

ABSTRACT

The antiviral activity induced by chitosan (CHT), and the mechanisms underlying it, were studied in a tobacco-tobacco necrosis necrovirus (TNV) pathosystem. Treatments with 0.1% CHT enhanced tobacco inducible defenses against TNV, reducing significantly the virus-induced necrotic lesions (in a range from 32% to 83%). In planta, this resistance was associated with a network of callose deposits, micro-oxidative bursts and micro-hypersensitive responses (micro-HRs), as assessed, respectively, by aniline blue, 3,3'-diaminobenzidine (DAB) and Evans blue staining. In order to verify if CHT-elicited cell death could be regarded as an apoptotic process, tobacco bright yellow 2 (BY2) cell cultures were treated with different CHT concentrations, ranging from 0.01% to 0.1%. After 6 h about half of the cultured cells incubated in 0.05% CHT were Evans blue positive, showing some typical morphological features of apoptosis, such as cytoplasm shrinkage and nuclear chromatin condensation. The latter was checked by 4',6-diamino-2-phenylindole (DAPI) and ethidium bromide nuclear staining and was visible already at 2 h after treatment. Moreover, the cell death kinetic induced by CHT was delayed by Verapamil(R), a calcium channel blocker. Finally, electrophoresis of genomic DNA extracted from cultured cell after 48 h treatment showed internucleosomal fragmentation, visualized as a distinct ladder of DNA bands corresponding to oligonucleosomal units.


Subject(s)
Antiviral Agents/pharmacology , Chitosan/pharmacology , DNA Fragmentation/drug effects , DNA, Plant/metabolism , Nicotiana/metabolism , Plant Viruses/metabolism , Chelating Agents/pharmacology , Dose-Response Relationship, Drug , Plant Diseases/virology , Nicotiana/cytology , Nicotiana/virology
15.
Cell Mol Life Sci ; 62(14): 1579-604, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15905961

ABSTRACT

Constitutive and alternative splicing events are regulated, in higher eukaryotes, by the action of multiple weak cis-acting elements and trans-acting factors. In particular, several evidences have suggested that silencers might have a fundamental role in preventing pseudoexon inclusion in mature transcripts and in defining constitutive exons by suppressing nearby decoy splice sites. Moreover, silencer elements allow the recruitment of regulatory factors to alternatively spliced exons, therefore participating in the modulation of alternative splicing pathways. Here we focus on splicing repression mechanisms in mammals, with particular concern to both exonic and intronic silencer elements, secondary structure formation and role in human genetic disease.Recently, in addition to the availability of a growing number of sequence elements deriving from the analysis of individual regulated exons, approaches have been developed that allowed the systematic identification of splicing silencers. These methods and are briefly described, as well as the motifs they retrieved, and summary of silenced exons is provided.


Subject(s)
Alternative Splicing , Silencer Elements, Transcriptional/genetics , Animals , Base Sequence , Binding Sites/genetics , Gene Expression Regulation , Heterogeneous-Nuclear Ribonucleoproteins/metabolism , Humans , Mice , Models, Biological , RNA Precursors/genetics , RNA Precursors/metabolism , Rats , Trans-Activators/metabolism
16.
Neurology ; 61(11): 1513-9, 2003 Dec 09.
Article in English | MEDLINE | ID: mdl-14663034

ABSTRACT

BACKGROUND: Caveolin-3 is the muscle-specific protein product of the caveolin gene family and an integral membrane component of caveolae. Mutations in the gene encoding caveolin-3 (CAV3) underlie four distinct disorders of skeletal muscle: the autosomal dominant form of limb-girdle muscular dystrophy type 1C (LGMD-1C), rippling muscle disease (RMD), sporadic and familial forms of hyperCKemia, and distal myopathy. OBJECTIVE: To characterize a multigenerational Italian family affected by an autosomal dominant myopathic disorder and to assess the expression of caveolin-3, dystrophin, dystrophin-associated glycoproteins, and neuronal nitric oxide synthase in the myocardium of an affected patient. METHODS: Clinical analysis involved 15 family members. Skeletal muscle expression of sarcolemmal proteins was evaluated by immunohistochemistry and western blot analysis in three affected individuals. Caveolar structures were analyzed through electron microscopy in muscle biopsies and in one heart biopsy. RESULTS: CAV3 genetic analysis showed a heterozygous 3-bp microdeletion (328-330del) in affected individuals, resulting in the loss of a phenylalanine (Phe97del) in the transmembrane domain. In the skeletal muscle, the mutation was associated with severe caveolin-3 deficiency and caveolar disorganization, whereas the expression of the other analyzed muscle proteins was unaltered. Remarkably, caveolin-3 was expressed in myocardium at a level corresponding to about 60% of that of control individuals and was correctly localized at the myocardial cell membranes, with preservation of cardiac myofiber caveolar structures. Clinical analysis revealed the concomitant presence in this family of the following phenotypes: RMD, LGMD, and hyperCKemia. CONCLUSIONS: Intrafamilial phenotypic heterogeneity is associated with caveolin-3 Phe97 microdeletion. The molecular network interacting with caveolin-3 in skeletal muscle and heart may differ.


Subject(s)
Caveolins/genetics , Muscle, Skeletal/metabolism , Muscular Diseases/genetics , Myocardium/metabolism , Sequence Deletion , Adult , Aged , Caveolin 3 , Caveolins/analysis , Caveolins/metabolism , Child, Preschool , Female , Humans , Male , Middle Aged , Muscle, Skeletal/chemistry , Muscle, Skeletal/pathology , Muscular Diseases/metabolism , Muscular Diseases/pathology , Myocardium/chemistry , Myocardium/ultrastructure , Pedigree
17.
Neuromuscul Disord ; 13(10): 788-95, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14678801

ABSTRACT

Dysferlin, the protein product of the dysferlin gene (DYSF), has been shown to have a role in calcium-induced membrane fusion and repair. Dysferlin is absent or drastically reduced in patients with the following autosomal recessive disorders: limb-girdle muscular dystrophy type 2B (LGMD-2B), Miyoshi myopathy (MM) and distal anterior compartment myopathy. To date, less than 45 mutations have been described in DYSF and a wide inter- and intra-familial variation in clinical phenotype has been associated with the same mutation. This observation underlines the relevance of any new report describing genotype/phenotype correlations in dysferlinopathic patient and families. Here we present the results of clinical, biochemical and genetic analysis performed on one MM and three LGMD Italian families. By screening the entire coding region of DYSF, we identified three novel mutations (two missense substitutions and one frame shift microdeletion). The possible existence of a founder effect for the Arg959Trp mutation in the Italian population is discussed.


Subject(s)
Founder Effect , Membrane Proteins , Muscle Proteins/deficiency , Muscle Proteins/genetics , Muscular Diseases/genetics , Muscular Dystrophies/genetics , Mutation/genetics , Adult , Aged , Arginine/genetics , DNA Mutational Analysis , Dysferlin , Female , Frameshift Mutation/genetics , Genetic Testing , Genotype , Humans , Italy , Male , Middle Aged , Muscular Diseases/metabolism , Muscular Dystrophies/metabolism , Mutation, Missense/genetics , Pedigree , Phenotype , Tryptophan/genetics
18.
Mol Psychiatry ; 8(2): 209-16, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12610653

ABSTRACT

Protein kinase C (PKC) has a key role in the signal transduction machinery involved in the regulation of amyloid precursor protein (APP) metabolism. Direct and indirect receptor-mediated activation of PKC has been shown to increase the release of soluble APP (sAPPalpha) and reduce the secretion of beta-amyloid peptides. Experimental evidence suggests that specific isoforms of PKC, such as PKCalpha and PKC epsilon, are involved in the regulation of APP metabolism. In this study, we characterized the role of PKCalpha in the regulated secretion of APP using wild-type SH-SY5Y neuroblastoma cells and cells transfected with a plasmid expressing PKCalpha antisense cDNA. Cells expressing antisense PKCalpha secrete less sAPPalpha in response to phorbol esters. In contrast, carbachol increases the secretion of sAPPalpha to similar levels in wild-type cells and in cells transfected with antisense PKCalpha by acting on APP metabolism through an indirect pathway partially involving the activation of PKC. These results suggest that the direct PKC-dependent activation of the APP secretory pathway is compromised by reduced PKCalpha expression and a specific role of this isoform in these mechanisms. On the other hand, indirect pathways that are also partially dependent on the mitogen-activated protein kinase signal transduction mechanism remain unaffected and constitute a redundant, compensatory mechanism within the APP secretory pathway.


Subject(s)
Amyloid beta-Protein Precursor/metabolism , Isoenzymes/metabolism , Neurons/enzymology , Neurons/metabolism , Protein Kinase C/metabolism , Carbachol/pharmacology , Carcinogens/pharmacology , Cholinergic Agents/pharmacology , Humans , Isoenzymes/genetics , Neuroblastoma , Protein Kinase C/genetics , Protein Kinase C-alpha , Receptors, Cholinergic/metabolism , Signal Transduction/drug effects , Signal Transduction/physiology , Tetradecanoylphorbol Acetate/pharmacology , Transfection , Tumor Cells, Cultured
19.
FEBS Lett ; 537(1-3): 30-4, 2003 Feb 27.
Article in English | MEDLINE | ID: mdl-12606026

ABSTRACT

We analyzed dystrophin alternative splicing events in a large number of Becker muscular dystrophy (BMD) affected individuals presenting major hot-spot deletions. Evidence is shown that altered splicing patterns in these patients do not directly result from the gene defect but probably derive from modifications in trans- rather than cis-acting factors. Several potential CUG-binding protein 2 (CUG-BP2) binding sites were found to be located in the dystrophin gene region encompassing exons 43-60 and CUG-BP2 transcript analysis indicated that not only expression levels are increased in dystrophic muscles but also that different CUG-BP2 isoforms are expressed. The possibility that CUG-BP2 might have a role in dystrophin splicing regulation is discussed.


Subject(s)
Alternative Splicing , Dystrophin/genetics , Muscle, Skeletal/metabolism , Muscular Dystrophy, Duchenne/genetics , Sequence Deletion , Base Sequence , Binding Sites , DNA-Binding Proteins/metabolism , Exons , Humans , RNA, Messenger/genetics , Transcription, Genetic
20.
Leukemia ; 17(1): 52-9, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12529660

ABSTRACT

The mechanism by which aplidine, a marine natural product in early clinical development as an anticancer agent, induces cell growth inhibition and apoptosis has been investigated in the human leukemia cell line MOLT-4. This cell line is characterized not only by the ability to secrete VEGF, but also for the presence on its surface of the VEGF receptor-1 (VEGFR-1). Previous studies from our laboratory concerned with evaluating early changes in gene expression induced by aplidine in MOLT-4 cells have shown that the drug decreases the expression of VEGFR-1 (Marchini et al. Proc Am Assoc Cancer Res 2000; 41: 833). Here, we report the ability of aplidine to block the VEGF/VEGFR-1 loop. We found that aplidine blocked VEGF secretion that was temporally followed by a decrease in both VEGF and VEGFR-1 production. Aplidine did not directly affect either VEGF transcription or stabilization of its mRNA. Transfection of MOLT-4 cells with an antisense VEGF cDNA construct, resulted in inhibition of colony formations. One clone, transfected with sense VEGF cDNA, secreting 8-10 times more VEGF than parental cells, was less sensitive to aplidine-induced cytotoxicity and apoptosis than control cells. Moreover, addition of VEGF in the medium decreased the activity of aplidine in MOLT-4 cells. These data demonstrate that aplidine inhibits the growth and induces apoptosis in MOLT-4 cells through the inhibition of VEGF secretion which blocks the VEGF/VEGFR-1 autocrine loop necessary for the growth of these cells.


Subject(s)
Antineoplastic Agents/pharmacology , Depsipeptides , Endothelial Growth Factors/antagonists & inhibitors , Leukemia, T-Cell/drug therapy , Lymphokines/antagonists & inhibitors , Peptides, Cyclic/pharmacology , Vascular Endothelial Growth Factor Receptor-1/antagonists & inhibitors , Apoptosis/drug effects , Autocrine Communication , Cell Division/drug effects , DNA Primers/chemistry , Dactinomycin/pharmacology , Electrophoretic Mobility Shift Assay , Endothelial Growth Factors/genetics , Endothelial Growth Factors/metabolism , Half-Life , Humans , Intercellular Signaling Peptides and Proteins/genetics , Intercellular Signaling Peptides and Proteins/metabolism , Leukemia, T-Cell/genetics , Leukemia, T-Cell/metabolism , Luciferases/metabolism , Lymphokines/genetics , Lymphokines/metabolism , Polymerase Chain Reaction , Promoter Regions, Genetic/drug effects , Protein Synthesis Inhibitors/pharmacology , RNA, Messenger/metabolism , Signal Transduction , Transfection , Tumor Cells, Cultured/drug effects , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factor Receptor-1/genetics , Vascular Endothelial Growth Factor Receptor-1/metabolism , Vascular Endothelial Growth Factors
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