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1.
Sci Data ; 6: 180309, 2019 01 15.
Article in English | MEDLINE | ID: mdl-30644852

ABSTRACT

Identifying floodplain boundaries is of paramount importance for earth, environmental and socioeconomic studies addressing riverine risk and resource management. However, to date, a global floodplain delineation using a homogeneous procedure has not been constructed. In this paper, we present the first, comprehensive, high-resolution, gridded dataset of Earth's floodplains at 250-m resolution (GFPLAIN250m). We use the Shuttle Radar Topography Mission (SRTM) digital terrain model and set of terrain analysis procedures for geomorphic floodplain delineations. The elevation data are processed by a fast geospatial tool for floodplain mapping available for download at https://github.com/fnardi/GFPLAIN. The GFPLAIN250m dataset can support many applications, including flood hazard mapping, habitat restoration, development studies, and the analysis of human-flood interactions. To test the GFPLAIN250m dataset, we perform a consistency analysis with floodplain delineations derived by flood hazard modelling studies in Europe.

2.
J Endocrinol Invest ; 41(5): 531-538, 2018 May.
Article in English | MEDLINE | ID: mdl-28948534

ABSTRACT

PURPOSE: The Italian consensus to classify thyroid cytology has provided a standardized reporting scheme, including the subdivision of indeterminate for malignancy TIR-3 category into TIR-3A (low-risk) and TIR-3B (high-risk). We aimed to present our experience on this subclassification by evaluating risks of malignancy and the validity in sorting nodules with dissimilar risks. Another aim was to compare our performance against the Bethesda system. METHODS: Fine-needle aspirates of 290 TIR-3 that underwent thyroid surgery at our hospital (2008-2013) were reviewed and divided into TIR-3A or TIR-3B, and AUS/FLUS or FN/SFN. Cytological diagnoses were then correlated to histology. Results were evaluated using univariate analysis. RESULTS: The subclassification into TIR-3A and TIR-3B differentiated hyperplastic nodules (p = 0.000) but not adenomas (p = 0.090). Rates of malignancy were significantly different between TIR-3A (10.2%) and TIR-3B (43.8%); TIR-3B malignancies were often papillary carcinomas (83%). TIR-3A/TIR-3B accounted for high sensitivity (84.5%; CI 79.7-88.4%), accuracy (64.1%; CI 58.6-69.6%) and NPV (89.8%; CI 85.6-93.0%) as opposed to modest specificity (55.8%; CI 49.9-61.6%) and PPV (43.8%; CI 38.1-49.8%). The rate of malignancy in AUS-FLUS was higher than in TIR-3A (p = 0.007), whereas it was not different between FN/SFN and TIR-3B (p = 0.337). Sensitivity of the Bethesda system was significantly lower respect to the Italian system. CONCLUSIONS: The study supports the Italian consensus showing a different risk of malignancy for TIR-3A as compared to TIR-3B. TIR-3A/TIR-3B subclassification is valid to sort out benign nodules (high NPV) and malignancies (high sensitivity) but not adenomas (modest specificity, low PPV). In our experience, sensitivity is the main difference between Italian and Bethesda systems.


Subject(s)
Adenocarcinoma, Follicular/diagnosis , Carcinoma, Papillary/diagnosis , Cytodiagnosis/methods , Thyroid Neoplasms/diagnosis , Thyroid Nodule/classification , Thyroid Nodule/diagnosis , Adolescent , Adult , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Young Adult
3.
HLA ; 88(3): 77-86, 2016 09.
Article in English | MEDLINE | ID: mdl-27440734

ABSTRACT

The HLA-G molecule belongs to the family of nonclassical human leukocyte antigen (HLA) class I. At variance to classical HLA class I, HLA-G displays (i) a low number of nucleotide variations within the coding region, (ii) a high structural diversity, (iii) a restricted peptide repertoire, (iv) a limited tissue distribution and (v) strong immune-suppressive properties. The physiological HLA-G surface expression is restricted to the maternal-fetal interface and to immune-privileged adult tissues. Soluble forms of HLA-G (sHLA-G) are detectable in various body fluids. Cellular activation and pathological processes are associated with an aberrant or a neo-expression of HLA-G/sHLA-G. Functionally, HLA-G and its secreted forms are considered to be key players in the induction of short- and long-term tolerance. Thus, its unique expression profile and tolerance-inducing functions render HLA-G/sHLA-G an attractive biomarker to monitor the systemic health/disease status and disease activity/progression for clinical approaches in disease management and treatments. Here, we place emphasis on (i) the current status of the tolerance-inducing functions by HLA-G/sHLA-G, (ii) the current complexity to implement this molecule as a meaningful clinical biomarker regarding the three dimensions of structural diversity (monomers, dimers and HLA-G-expressing extracellular vesicles) with its functional implications, and (iii) novel and future approaches to detect and quantify sHLA-G structures and functions.


Subject(s)
Extracellular Vesicles/immunology , HLA-G Antigens/genetics , Immune System Diseases/diagnosis , Immune Tolerance , Biomarkers/metabolism , Extracellular Vesicles/chemistry , Female , Fetus/immunology , Gene Expression Regulation , HLA-G Antigens/chemistry , HLA-G Antigens/immunology , Humans , Immune System Diseases/genetics , Immune System Diseases/immunology , Immune System Diseases/pathology , Placenta/immunology , Polymorphism, Genetic , Pregnancy , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Isoforms/immunology , Protein Multimerization , Solubility
4.
Nanotechnology ; 24(38): 384012, 2013 Sep 27.
Article in English | MEDLINE | ID: mdl-23999495

ABSTRACT

In a neural network, neuron computation is achieved through the summation of input signals fed by synaptic connections. The synaptic activity (weight) is dictated by the synchronous firing of neurons, inducing potentiation/depression of the synaptic connection. This learning function can be supported by the resistive switching memory (RRAM), which changes its resistance depending on the amplitude, the pulse width and the bias polarity of the applied signal. This work shows a new synapse circuit comprising a MOS transistor as a selector and a RRAM as a variable resistance, displaying spike-timing dependent plasticity (STDP) similar to the one originally experienced in biological neural networks. We demonstrate long-term potentiation and long-term depression by simulations with an analytical model of resistive switching. Finally, the experimental demonstration of the new STDP scheme is presented.


Subject(s)
Electronics , Models, Neurological , Nanotechnology/instrumentation , Nanotechnology/methods , Neuronal Plasticity , Synapses , Action Potentials , Computer Simulation , Computers, Molecular , Nerve Net
5.
G Chir ; 33(11-12): 387-91, 2012.
Article in English | MEDLINE | ID: mdl-23140922

ABSTRACT

Fine needle aspiration cytology (FNAC) is the more accurate diagnostic method for cervical lymph node (CLN) metastasis from differentiated thyroid cancers (DTC). However, FNAC diagnosis of cystic CLN is, in most cases, uninformative due to inadequate cellularity. Recently, thyroglobulin (Tg) detection in FNAC needle washout fluid has been shown to improve the diagnostic accuracy of FNAC, and its routine association with cytology is recommended. We here describe the case of a 20 yr old girl complaining of the recent appearance of palpable non-painful laterocervical nodes in the neck. Ultrasound examination revealed the presence of 3 cystic CLNs and 2 mixed thyroid nodules, with the larger one showing irregular margins. On the latter, and on 2 larger CLNs, FNAC was performed, and both Tg protein and mRNA were determined in the needle washout. The cytological analysis was not diagnostic for the two CLNs, while that of the thyroid nodule reported the presence of colloid and groups of thyrocytes with normal morphology. Both CLNs showed, however, high levels of Tg protein and were positive for Tg mRNA, suggestive of metastatic DTC. Based on these findings, the FNAC analysis was performed on the second smaller thyroid nodule suggesting (Tir4) the presence of PTC. The patient was then subjected to total thyroidectomy with lymph nodes resection of the central and homolateral compartments. The histological diagnosis confirmed the presence of a PTC in the small nodule and metastatic lymph nodes. In conclusion, this case confirms that the cytological diagnosis of cystic lymph nodes is challenging, and that the measurement of Tg protein and/or mRNA in the needle washout may overcome this limitation.


Subject(s)
Biopsy, Fine-Needle , Carcinoma, Papillary/chemistry , Carcinoma, Papillary/diagnosis , Neck/pathology , Thyroglobulin/analysis , Thyroid Neoplasms/chemistry , Thyroid Neoplasms/diagnosis , Adult , Biomarkers/analysis , Carcinoma, Papillary/secondary , Carcinoma, Papillary/surgery , Female , Follow-Up Studies , Humans , Lymph Node Excision , Neck/surgery , Neoplasm Staging , Predictive Value of Tests , Sensitivity and Specificity , Thyroid Neoplasms/secondary , Thyroid Neoplasms/surgery , Thyroidectomy , Treatment Outcome , Ultrasonography, Interventional
6.
Clin Ter ; 163(5): e303-6, 2012.
Article in English | MEDLINE | ID: mdl-23099977

ABSTRACT

OBJECTIVES: Aim of the study was to identify, in 59 operated patients affected by medullary thyroid carcinoma (MTC), the recurrence rate, survival, mortality and incidences of surgically derived hypoparathyroidism and recurrent laryngeal nerve injury (RLNI). MATERIALS AND METHODS: Based on pre-surgical diagnosis of the 59 patients included in the study, 35 underwent total thyroidectomy with central neck dissection (Group A), 14 total thyroidectomy, central neck dissection and monolateral functional neck dissection (Group B) and 10 total thyroidectomy central neck dissection, bilateral functional neck dissection (Group C). Overall survival, recurrences, incidence of hypoparathyroidism and RLNI were evaluated. RESULTS: The survival and recurrences were not statistically different among the three Groups. In Group B there was major probability of re-operation (p=0.042). The mortality rate was clearly major in Group C (p=0.003) due to the stage of pathology. Group C showed a high number of hypoparatiroidism compared to Group B, and B compared to A. In Group A there was only one unexpected RLNI; in 5 cases, 3 in Group B and 2 in Group C, there were a necessity laringeal section due to nerve tumor involvement. CONCLUSIONS: From our data it appears clearly that disease outcome following the different surgical approaches is mainly determinated by the stage of the disease at diagnosis. However, the finding that patients in Group A and B showed a high rate of local-regional recurrences may suggest that homolateral lymphadenectomy in Group A patients and bilateral lymphadenectomy in Group B patients should be always performed.


Subject(s)
Thyroid Neoplasms/surgery , Thyroidectomy/methods , Carcinoma, Neuroendocrine , Female , Humans , Male , Middle Aged , Neck Dissection , Neoplasm Recurrence, Local/epidemiology , Survival Rate , Thyroid Neoplasms/mortality , Thyroidectomy/adverse effects
7.
Mol Phylogenet Evol ; 65(2): 523-34, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22828178

ABSTRACT

We investigated the evolution of the Asian francolins, five little known species in the genus Francolinus (Phasianidae). Evolutionary affinities of two of these species, F. gularis (swamp francolin) and F. pondicerianus (grey francolin), has long remained unclear. In contrast, the other three species, F. pintadeanus (Chinese francolin), F. pictus (painted francolin) and F. francolinus (black francolin) have been cast among the "spotted francolins" on a morphological and ecological basis. Previous molecular DNA investigations including Asian francolins mostly relied upon partial gene sequencing of one specimen per species (no more than three species and with the exclusion of F. pictus). Therefore, fundamental questions do persist. What relationship exists among the spotted and the other Asian francolins? What is the geographic origin of the black francolin, the species with the largest distribution range? How did the geological history influence the diversification of francolins across Asia? We sequenced the entire Control Region of the mitochondrial DNA in 228 samples of all five Asian francolin species, which were collected in 16 countries (from East Europe to East Asia). We constructed a molecular phylogeny according to four different procedures. We showed the monophyly of each of the Asian francolins and the spotted group, while that of the entire Asian group was presumed according to a biogeographical model we proposed. The splitting of the genus Francolinus occurred ~17.4 Ma (95% HPD: 13.4-22.1) while the spotted francolins diverged ~10.5 Ma (7.0-14.9). We resolved the most recent common ancestor to painted and black francolin as being in the Indian sub-continent, thus suggesting a westwards adaptive radiation of the latter. In Pakistan, we identified F. f. asiae representatives in the Northern Areas and in the Sindh. The latter represents a relict population of Indian fauna within the Pakistani range of the Great Rann of Kachchh.


Subject(s)
Evolution, Molecular , Galliformes/classification , Genetic Speciation , Phylogeny , Animals , Bayes Theorem , DNA, Mitochondrial/genetics , Galliformes/genetics , Likelihood Functions , Phylogeography , Sequence Analysis, DNA
8.
Pediatr Med Chir ; 33(2): 73-9, 2011.
Article in Italian | MEDLINE | ID: mdl-22111289

ABSTRACT

This study aims to present an overview of feeding and oral-motor assessment scales currently available for the paediatric age group through a review of literature from 1980 to 2009.


Subject(s)
Deglutition/physiology , Eating/physiology , Motor Skills/physiology , Mouth/physiology , Child , Child, Preschool , Humans , Infant , Infant, Newborn
9.
Nanotechnology ; 22(25): 254022, 2011 Jun 24.
Article in English | MEDLINE | ID: mdl-21572207

ABSTRACT

NiO films display unipolar resistance switching characteristics, due to the electrically induced formation and rupture of nanofilaments. While the applicative interest for possible use in highly dense resistance switching memory (RRAM) is extremely high, switching phenomena pose strong fundamental challenges in understanding the physical mechanisms and models. This work addresses the set and reset mechanisms for the formation and rupture of nanofilaments in NiO RRAM devices. Reset is described in terms of thermally-accelerated diffusion and oxidation processes, and its resistance dependence is explained by size-dependent Joule heating and oxidation. The filament is described as a region with locally-enhanced doping, resulting in an insulator-metal transition driven by structural and chemical defects. The set mechanism is explained by a threshold switching effect, triggering chemical reduction and a consequent local increase of metallic doping. The possible use of the observed resistance-dependent reset and set parameters to improve the memory array operation and variability is finally discussed.

10.
J Endocrinol Invest ; 34(3): e64-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20855934

ABSTRACT

Aim of the study was to assess the presence of structural changes in the complex carbohydrate chains of thyroid epithelia undergoing neoplastic transformation. We investigated thyroid cells from neoplastic lesions using a panel of lectins with specific affinity for distinct carbohydrate residues. Sixty samples of thyroid tissue, including normal, hyperplastic and neoplastic lesions were obtained from surgical specimens and blindly evaluated with lectin stains. Confocal microscopy was used to obtain three-dimensional (3-D) images of the samples with a positive reaction. Wheat germ agglutinin (WGA) was consistently positive on the apical membrane of papillary thyroid carcinomas (PTC), was weakly expressed in follicular carcinomas (FC) and resulted negative in normal thyrocytes and in benign conditions. The 3-D microscopy model showed that the WGA staining pattern in light microscopy corresponds to a continuous layer on the luminal surface of both papillary and tubular structures of PTC cells. The other lectins under evaluation did not provide any significant result. In conclusion, in PTC the apical border of thyrocytes showed a strong, specific and consistent staining with WGA. These findings may be related to a modified interaction of thyroglobulin molecule with thyroid cell membrane and with the expression of molecules that are involved in the process of tumorigenesis and tumor progression.


Subject(s)
Cell Membrane/metabolism , Phenotype , Thyroid Gland/cytology , Thyroid Gland/pathology , Thyroid Neoplasms/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma , Carcinoma, Papillary , Cell Transformation, Neoplastic/pathology , Female , Humans , Lectins/metabolism , Male , Middle Aged , Thyroid Cancer, Papillary , Thyroid Neoplasms/metabolism , Young Adult
11.
Mol Phylogenet Evol ; 57(2): 678-86, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20723608

ABSTRACT

The evolutionary history of the olive fly, Bactrocera oleae, was reconstructed in a phylogenetic and coalescent framework using full mitochondrial genome data from 21 individuals covering the entire worldwide distribution of the species. Special attention was given to reconstructing the timing of the processes under study. The early subdivision of the olive fly reflects the Quaternary differentiation between Olea europea subsp. europea in the Mediterranean area and the two lineages of Olea europea subsp. cuspidata in Africa and Asia, pointing to an early and close association between the olive fly and its host. The geographic structure and timing of olive fly differentiation in the Mediterranean indicates a clear connection with the post-glacial recolonization of wild olives in the area, and is irreconcilable with the early historical process of domestication and spread of the cultivated olive from its Levantine origin. Therefore, we suggest an early co-history of the olive fly with its wild host during the Quaternary and post-glacial periods and a multi-regional shift of olive flies to cultivated olives as these cultivars gradually replaced wild olives in historical times.


Subject(s)
Genome, Mitochondrial/genetics , Olea , Phylogeny , Tephritidae/classification , Tephritidae/genetics , Animals , Olea/classification , Olea/genetics , Olea/parasitology
12.
Bull Entomol Res ; 100(6): 741-7, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20569524

ABSTRACT

A molecular tool, focused on the mitochondrial Control Region (CR), was developed to discriminate the two hawthorn-feeding psyllid species, Cacopsylla melanoneura (Förster) and C. affinis (Löw), and to estimate their frequencies in mixed populations. The test was carried out in paired and single-tube amplifications and validated analysing 52 male specimens previously determined by morphological analysis. The frequencies of the two species in mixed populations in the Aosta Valley (northwestern Italy) were analysed. The presence and type of 16SrX-group phytoplasmas was detected by nested PCR and RFLP tests in both species. C. melanoneura was the predominant species (86.5%; 80.4-91.2 CI); of these, 0.9% of the samples were positive for 'Ca. Phytoplasma mali' and 1.8% for 'Ca. Phytoplasma pyri'. One of 21 specimens of C. affinis was positive for 'Ca. Phytoplasma pyri'. The test also allowed us to identify two genetic variants of C. melanoneura, depending on the presence or absence of a 56 bp indel; these were named WI (with indel) and WOI (without indel), respectively. Further analyses were carried out on C. melanoneura specimens collected in apple orchards at six different locations in northern Italy where different levels of transmission efficiency have been described. Our preliminary observations suggest that some differences might exist between the two genetic variants in their ability to transmit phytoplasmas and to colonise different host plants.


Subject(s)
Hemiptera/genetics , Hemiptera/microbiology , Phytoplasma/physiology , Polymerase Chain Reaction , Animals , Crataegus/parasitology , Hemiptera/classification , Italy , Locus Control Region/genetics , Male , Malus/parasitology , Phytoplasma/genetics , Population Density , Reproducibility of Results , Species Specificity
14.
Mol Ecol ; 19(2): 386-400, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20015142

ABSTRACT

The North-Western Mediterranean basin is well known for its high number of relictual endemic taxa, and has been indicated as one of the world's major biodiversity hotspots at the species level. A possible contributing factor may be long-term persistence of populations and their prolonged stability. This study was designed to investigate the phylogeographic structure of three common species of the genus Lepidocyrtus (Hexapoda: Collembola), soil-dwelling arthropods characterized by limited dispersal capabilities and generally associated with forest habitats. We observed a remarkable geographic structure, with numerous deeply divergent genetic lineages occupying islands as well as mainland sites with no apparent gene flow among most sites, even across distances of only tens of kilometres. The reconstructed time frame for the evolution of these lineages suggests divergence between 5 and 15 Ma. This indicates a remarkably ancient origin and long-term persistence of individual lineages over a fine geographic scale despite the occurrence of abrupt sea level and climatic fluctuations in the area. This further suggests that currently recognized morphological species might be a serious underestimation of the true springtail biodiversity within this region.


Subject(s)
Arthropods/genetics , Evolution, Molecular , Genetics, Population , Phylogeny , Animals , Biodiversity , Gene Flow , Geography , Haplotypes , Mediterranean Region , Sequence Alignment , Sequence Analysis, DNA
15.
Insect Mol Biol ; 18(1): 45-54, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19016914

ABSTRACT

Acetylcholinesterase (AChE) is a key enzyme of the cholinergic nerve system. Of the two forms found in insects, the predominant one is active in the synapses and is the target of organophosphate and carbamate insecticides, while the role of the second is currently unknown. Two acetylcholinesterase cDNAs from the basal hexapod Orchesella villosa have been characterized and compared with others reported form insects. One form conforms well to the typical structure, while the other is characterized by an unusual 3' region. No amino acid mutation could be directly associated with known resistance mutations in other insect species or to a clear signal of selection in the distribution of alleles, although the action of some population process is suggested.


Subject(s)
Acetylcholinesterase/genetics , Arthropods/enzymology , Arthropods/genetics , Acetylcholinesterase/chemistry , Amino Acid Sequence , Animals , Arthropods/classification , Genetic Variation , Mutation , Phylogeny , Sequence Alignment
16.
Cytogenet Genome Res ; 119(1-2): 21-6, 2007.
Article in English | MEDLINE | ID: mdl-18160777

ABSTRACT

Deletion of the CDKN2A locus at 9p21.3 has been reported to be a poor prognostic sign in the Ewing sarcoma family of tumours. In clinical applications CDKN2A deletion is primarily detected using fluorescent in situ hybridisation (FISH) with a commercial probe, size approximately 190 kb. Due to limitations in resolution, FISH analysis may fail to detect microdeletions smaller than 190 kb. In the present study, we performed 44K array comparative genomic hybridisation (CGH) on eleven Ewing sarcoma cell lines and 26 tissue samples in order to define the sizes of 9p21.3 deletions. Microarray CGH analysis revealed 9p21.3 deletions encompassing the CDKN2A locus in eight cell lines (73%) and in six tumours (23%). In four cases (two cell lines and two tissue samples) the deletion was less than 190 kb in size. In one cell line sample, we detected a microdeletion of approximately 58 kb in 9p21.3 harbouring the CDKN2A locus. We confirmed this result using 244K microarray CGH and TaqMan quantitative RT-PCR analysis and further performed FISH analysis on this cell line sample. Here, we show that CDKN2A FISH analysis can give false negative results in cases with small microdeletions. Our results suggest that new and more accurate FISH methods should be developed for detection of deletions in the CDKN2A locus.


Subject(s)
Chromosome Deletion , Chromosomes, Human, Pair 9/genetics , Cyclin-Dependent Kinase Inhibitor p16/genetics , In Situ Hybridization, Fluorescence , Sarcoma, Ewing/enzymology , Sarcoma, Ewing/genetics , Cells, Cultured , False Negative Reactions , Female , Genome, Human/genetics , Humans , Male , Oligonucleotide Array Sequence Analysis , RNA, Messenger/genetics , Sarcoma, Ewing/diagnosis
17.
Gene ; 396(1): 66-74, 2007 Jul 01.
Article in English | MEDLINE | ID: mdl-17433576

ABSTRACT

The complete mitochondrial genome of the oriental fruit fly Bactrocera dorsalis s.s. has been sequenced, and is here described and compared with the homologous sequences of Bactrocera oleae and Ceratitis capitata. The genome is a circular molecule of 15,915 bp, and encodes the set of 37 genes generally found in animal mitochondrial genomes. The structure and organization of the molecule is typical and similar to the two closely related species B. oleae and C. capitata, although it presents an interesting case of putative intra-molecular recombination. The relevance of the growing comparative dataset of tephritid complete mitochondrial genomes is discussed in relation to the possibility to develop robust assays for species discrimination in quarantine and agricultural monitoring practices, as well as basic phylogeography/population genetic studies.


Subject(s)
DNA, Mitochondrial/genetics , Genome, Insect/genetics , Tephritidae/genetics , Animals , Base Composition/genetics , Base Sequence , Codon/genetics , DNA, Intergenic/genetics , Genes, Insect , Genetic Variation , Molecular Sequence Data , Nucleic Acid Conformation , Open Reading Frames/genetics , RNA, Ribosomal/genetics , RNA, Transfer/chemistry , RNA, Transfer/genetics , Recombination, Genetic/genetics
18.
Gene ; 381: 49-61, 2006 Oct 15.
Article in English | MEDLINE | ID: mdl-16919404

ABSTRACT

Complete mitochondrial genome sequences are presented from two dipluran hexapods (i.e., a group of "primarily wingless insects") of the genus Campodea and compared to those of other arthropods. Their gene order is the same as in most other hexapods and crustaceans. Structural changes have occurred in tRNA-C, tRNA-R, tRNA-S1 and tRNA-S2 as well as in both ribosomal RNAs. These mtDNAs have striking biases in nucleotide and amino acid composition. Although the two Campodea species are morphologically highly similar, their genetic divergence is larger than expected, suggesting a long evolutionary history, perhaps under stable ecological conditions.


Subject(s)
DNA, Mitochondrial , Genetic Drift , Genome, Insect , Insecta/genetics , Animals , Base Composition , Base Sequence , Evolution, Molecular , Mitochondria/genetics , Molecular Sequence Data , Nucleic Acid Conformation , Phylogeny , Polymerase Chain Reaction , RNA, Transfer/genetics
19.
Dig Liver Dis ; 37(11): 826-31, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16169304

ABSTRACT

BACKGROUND: Antibiotic resistance is the main reason of failure for H. pylori eradication and beta-lactamases produced by resistant H. pylori strains is a possible mechanism underlying ineffectiveness of an amoxycillin-based triple therapy. AIM: To investigate the benefit of using clavulanic acid associated with amoxycillin compared with amoxycillin alone in a standard triple therapy. METHODS: A total 172 H. pylori-positive dyspeptic patients were randomised to a daily treatment with esomeprazole (20 mg bid), clarithromycin (500 mg bid) and either amoxycillin plus clavulanic acid (1 g bid) or amoxycillin (1 g bid) alone for 1 week. H. pylori status was defined by histology and urea breath test at entry and following 8 weeks from the end of therapy by urea breath test and antigen faecal assessment. RESULTS: At intention-to-treat and per-protocol analysis eradication rates achieved by amoxycillin plus clavulanic acid (72 and 78%) were higher, but not significantly, than those achieved by amoxycillin alone triple therapy (62 and 72%). Compliance was good, side-effects mild and with a similar incidence in both regimens. CONCLUSIONS: Clavulanic acid supplemented to amoxycillin-based standard triple therapy does not significantly increase the H. pylori eradication rate with standard triple therapy.


Subject(s)
Amoxicillin/therapeutic use , Clavulanic Acid/therapeutic use , Enzyme Inhibitors/therapeutic use , Helicobacter Infections/drug therapy , Helicobacter pylori/enzymology , beta-Lactamases/metabolism , Clavulanic Acid/pharmacology , Enzyme Inhibitors/pharmacology , Feces/microbiology , Female , Helicobacter pylori/drug effects , Humans , Male , Middle Aged , Multivariate Analysis
20.
Dig Liver Dis ; 37(8): 571-6, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15996628

ABSTRACT

BACKGROUND: Primary antibiotic-resistance and poor compliance are the main causes of Helicobacter pylori eradication failure of standard regimens. AIM: To investigate eradication rate, patient compliance and tolerability of a 1-week once-daily levofloxacin plus azithromycin triple therapy versus the standard twice-daily triple therapy. PATIENTS AND METHODS: A total of 164 H. pylori-positive patients were randomised to either esomeprazole 20mg, levofloxacin 500 mg and azithromycin 500 mg once-daily (ELAz) or esomeprazole 20mg, clarithromycin 500 mg and amoxycillin 1g twice-daily (ECA) for 1 week. H. pylori infection was defined at entry by histology and urea breath test; cure of infection was determined both by negative urea breath test and H. pylori stool antigens. RESULTS: H. pylori eradication rates of ELAz and ECA were similar at intention-to-treat (both 65%) and per-protocol analyses (70% versus 76%, respectively). Incidence of poor compliance was lower, although not significantly, in patients randomised to ELAz than to ECA (4% versus 10%); tolerability was significantly higher for ELAz than for ECA (88% versus 70%; P=0.01). CONCLUSIONS: Once-daily levofloxacin plus azithromycin-based triple therapy achieves an H. pylori eradication rate comparable to that of standard twice-daily triple therapy, but is associated with higher patient compliance and might even be better tolerated.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Ulcer Agents/administration & dosage , Azithromycin/administration & dosage , Esomeprazole/administration & dosage , Helicobacter Infections/drug therapy , Levofloxacin , Ofloxacin/administration & dosage , Anti-Bacterial Agents/adverse effects , Anti-Ulcer Agents/adverse effects , Azithromycin/adverse effects , Drug Administration Schedule , Drug Therapy, Combination , Esomeprazole/adverse effects , Female , Helicobacter pylori , Humans , Male , Middle Aged , Ofloxacin/adverse effects , Patient Compliance/statistics & numerical data , Treatment Outcome
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