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71.
Previous attempts to resolve the Ceratitis FAR complex (Ceratitis
fasciventris, Ceratitis
anonae, Ceratitis
rosa, Diptera, Tephritidae) showed contrasting results and revealed the occurrence of five microsatellite genotypic clusters (A, F1, F2, R1, R2). In this paper we explore the potential of wing morphometrics for the diagnosis of FAR morphospecies and genotypic clusters. We considered a set of 227 specimens previously morphologically identified and genotyped at 16 microsatellite loci. Seventeen wing landmarks and 6 wing band areas were used for morphometric analyses. Permutational multivariate analysis of variance detected significant differences both across morphospecies and genotypic clusters (for both males and females). Unconstrained and constrained ordinations did not properly resolve groups corresponding to morphospecies or genotypic clusters. However, posterior group membership probabilities (PGMPs) of the Discriminant Analysis of Principal Components (DAPC) allowed the consistent identification of a relevant proportion of specimens (but with performances differing across morphospecies and genotypic clusters). This study suggests that wing morphometrics and PGMPs might represent a possible tool for the diagnosis of species within the FAR complex. Here, we propose a tentative diagnostic method and provide a first reference library of morphometric measures that might be used for the identification of additional and unidentified FAR specimens. 相似文献
72.
Kinzel O Alfieri A Altamura S Brunetti M Bufali S Colaceci F Ferrigno F Filocamo G Fonsi M Gallinari P Malancona S Hernando JI Monteagudo E Orsale MV Palumbi MC Pucci V Rowley M Sasso R Scarpelli R Steinkühler C Jones P 《Bioorganic & medicinal chemistry letters》2011,21(15):4429-4435
The Hedgehog (Hh-) signaling pathway is a key developmental pathway which gets reactivated in many human tumors, and smoothened (Smo) antagonists are emerging as novel agents for the treatment of malignancies dependent on the Hh-pathway, with the most advanced compounds demonstrating encouraging results in initial clinical trials. A novel series of potent bicyclic hydantoin Smo antagonists was reported in the preceding article, these have been resolved, and optimized to identify potent homochiral derivatives with clean off-target profiles and good pharmacokinetic properties in preclinical species. While showing in vivo efficacy in mouse allograft models, unsubstituted bicyclic tetrahydroimidazo[1,5-a]pyrazine-1,3(2H,5H)-diones were shown to epimerize in plasma. Alkylation of the C-8 position blocks this epimerization, resulting in the identification of MK-5710 (47) which was selected for further development. 相似文献
73.
Li B Cardinale SC Butler MM Pai R Nuss JE Peet NP Bavari S Bowlin TL 《Bioorganic & medicinal chemistry》2011,19(24):7338-7348
Botulinum neurotoxins (BoNTs) are the most lethal of biological substances, and are categorized as class A biothreat agents by the Centers for Disease Control and Prevention. There are currently no drugs to treat the deadly flaccid paralysis resulting from BoNT intoxication. Among the seven BoNT serotypes, the development of therapeutics to counter BoNT/A is a priority (due to its long half-life in the neuronal cytosol and its ease of production). In this regard, the BoNT/A enzyme light chain (LC) component, a zinc metalloprotease responsible for the intracellular cleavage of synaptosomal-associated protein of 25 kDa, is a desirable target for developing post-BoNT/A intoxication rescue therapeutics. In an earlier study, we reported the high throughput screening of a library containing 70,000 compounds, and uncovered a novel class of benzimidazole acrylonitrile-based BoNT/A LC inhibitors. Herein, we present both structure–activity relationships and a proposed mechanism of action for this novel inhibitor chemotype. 相似文献
74.
Iacobellis G Malavazos AE Corsi MM 《The international journal of biochemistry & cell biology》2011,43(12):1651-1654
Epicardial fat is the visceral fat depot of heart. It is a metabolically active organ with anatomical and functional contiguity to the myocardium. A dichotomous role has been attributed to the epicardial fat. Under physiological conditions, epicardial fat displays biochemical and thermogenic cardio-protective properties. Under pathological circumstances epicardial fat can locally affect the heart and coronary arteries through vasocrine or paracrine secretion of pro-inflammatory cytokines. Epicardial fat can be measured with imaging techniques. Epicardial fat thickness reflects intra-abdominal and myocardial fat and correlates with metabolic syndrome and coronary artery disease. Epicardial fat measurement may play a role in the stratification of the cardio-metabolic risk and serve as therapeutic target. Weight loss and anti-inflammatory drugs targeting the fat may modulate epicardial fat. Because epicardial and myocardial tissues share the same coronary arterial supply it is reasonable to hypothesize that improved local vascularisation may resume epicardial fat to its physiological role. 相似文献
75.
76.
Rea M Kullmann S Veit R Casile A Braun C Belardinelli MO Birbaumer N Caria A 《PloS one》2011,6(10):e26290
Prospective memory (PM) describes the ability to execute a previously planned action at the appropriate point in time. Although behavioral studies clearly showed that prospective memory performance is affected by the emotional significance attributed to the intended action, no study so far investigated the brain mechanisms subserving the modulatory effect of emotional salience on PM performance. The general aim of the present study was to explore brain regions involved in prospective memory processes when PM cues are associated with emotional stimuli. In particular, based on the hypothesised critical role of the prefrontal cortex in prospective memory in the presence of emotionally salient stimuli, we expected a stronger involvement of aPFC when the retrieval and execution of the intended action is cued by an aversive stimulus. To this aim BOLD responses of PM trials cued by aversive facial expressions were compared to PM trials cued by neutral facial expressions. Whole brain analysis showed that PM task cued by aversive stimuli is differentially associated with activity in the right lateral prefrontal area (BA 10) and in the left caudate nucleus. Moreover a temporal shift between the response of the caudate nucleus that preceded that of aPFC was observed. These findings suggest that the caudate nucleus might provide an early analysis of the affective properties of the stimuli, whereas the anterior lateral prefrontal cortex (BA10) would be involved in a slower and more deliberative analysis to guide goal-directed behaviour. 相似文献
77.
Background
Leptospirosis is a disease which occurs worldwide but particularly affects tropical areas. Transmission of the disease is dependent on its excretion by reservoir animals and the presence of moist environment which allows the survival of the bacteria.Methods and Findings
A retrospective study was undertaken to describe seasonal patterns of human leptospirosis cases reported by the Centre National de Références des Leptospiroses (CNRL, Pasteur Institute, Paris) between 1998 and 2008, to determine if there was an association between the occurrence of diagnosed cases and rainfall, temperature and global solar radiation (GSR). Meteorological data were recorded in the town of Saint-Benoît (Météo France “Beaufonds-Miria” station), located on the windward (East) coast. Time-series analysis was used to identify the variables that best described and predicted the occurrence of cases of leptospirosis on the island. Six hundred and thirteen cases were reported during the 11-year study period, and 359 cases (58.56%) were diagnosed between February and May. A significant correlation was identified between the number of cases in a given month and the associated cumulated rainfall as well as the mean monthly temperature recorded 2 months prior to diagnosis (r = 0.28 and r = 0.23 respectively). The predictive model includes the number of cases of leptospirosis recorded 1 month prior to diagnosis (b = 0.193), the cumulated monthly rainfall recorded 2 months prior to diagnosis (b = 0.145), the average monthly temperature recorded 0 month prior to diagnosis (b = 3.836), and the average monthly GSR recorded 0 month prior to diagnosis (b = −1.293).Conclusions
Leptospirosis has a seasonal distribution in Reunion Island. Meteorological data can be used to predict the occurrence of the disease and our statistical model can help to implement seasonal prevention measures. 相似文献78.
α-crystallin, the major constituent of human lens, is a member of the heat-shock proteins family and it is known to have a quaternary structural transition at . The presence of calcium ions and/or temperature changes induce supramolecular self-aggregation, a process of relevance in the cataractogenesis. Here we investigate the potential effect of the bovine α-crystallin's structural transition on the self-aggregation process. Along all the temperatures investigated, aggregation proceeds by forming intermediate molecular assemblies that successively aggregate in clusters. The final morphology of the aggregates, above and below Tc, is similar, but the aggregation kinetics are completely different. The size of the intermediate molecular assemblies, and their repulsive energy barrier show a marked increase while crossing . Our results highlight the key role of heat modified form of α-crystallin in protecting from aggregation and preserving the transparency of the lens under hyperthermic conditions. 相似文献
79.
Massimiliano Calabrese Richard Reynolds Roberta Magliozzi Marco Castellaro Aldo Morra Antonio Scalfari Gabriele Farina Chiara Romualdi Alberto Gajofatto Marco Pitteri Maria Donata Benedetti Salvatore Monaco 《PloS one》2015,10(8)
Background
Both gray-matter (GM) atrophy and lesions occur from the earliest stages of Multiple Sclerosis (MS) and are one of the major determinants of long-term clinical outcomes. Nevertheless, the relationship between focal and diffuse GM damage has not been clarified yet. Here we investigate the regional distribution and temporal evolution of cortical thinning and how it is influenced by the local appearance of new GM lesions at different stages of the disease in different populations of MS patients.Methods
We studied twenty MS patients with clinically isolated syndrome (CIS), 27 with early relapsing-remitting MS (RRMS, disease duration <5 years), 29 with late RRMS (disease duration ≥ 5 years) and 20 with secondary-progressive MS (SPMS). The distribution and evolution of regional cortical thickness and GM lesions were assessed during 5-year follow-up.Results
The results showed that new lesions appeared more frequently in hippocampus and parahippocampal gyri (9.1%), insula (8.9%), cingulate cortex (8.3%), superior frontal gyrus (8.1%), and cerebellum (6.5%). The aforementioned regions showed the greatest reduction in thickness/volume, although (several) differences were observed across subgroups. The correlation between the appearance of new cortical lesions and cortical thinning was stronger in CIS (r2 = 50.0, p<0.001) and in early RRMS (r2 = 52.3, p<0.001), compared to late RRMS (r2 = 25.5, p<0.001) and SPMS (r2 = 6.3, p = 0.133).Conclusions
We conclude that GM atrophy and lesions appear to be different signatures of cortical disease in MS having in common overlapping spatio-temporal distribution patterns. However, the correlation between focal and diffuse damage is only moderate and more evident in the early phase of the disease. 相似文献80.
Gambarino S Costa C Astegiano S Piasentin EA Segoloni GP Cavallo R Bergallo M 《Molecular biotechnology》2011,49(2):151-158
Polyomavirus BK latently persist in different sites, including the renourinary tract, and may reactivate causing nephropathy
in renal transplant recipients or hemorrhagic cystitis in bone marrow recipients. Based on the sequence of the VP1 gene, four
genotypes have been described, corresponding to the four serologically differentiated subtypes I–IV, with different prevalence
and geographic distribution. In this study, the development and clinical validation of four different Real-Time PCR assays
for the detection and discrimination of BKV genotypes as a substitute of DNA sequencing are described. 379 BK VP1 sequences,
belonging to the main four genotypes, were aligned and “hot spots” of mutation specific for all the strains or isolates were
identified. Specific primers and probes for the detection and discrimination of each genotype by four Real-Time PCR assays
were designed and technically validated. Subsequently, the four Real-Time PCR assays were used to test 20 BK-positive urine
specimens from renal transplant patients, and evidenced a prevalence of BK genotype I, as previously reported in Europe. Results
were confirmed by sequencing. The availability of a rapid and simple genotyping method could be useful for the evaluation
of BK genotypes prevalence and studies on the impact of the infecting genotype on viral biological behavior, pathogenic role,
and immune evasion strategies. 相似文献