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1.
Colour polymorphism (CP) is widespread in animals, but mechanisms underlying morph evolution and maintenance are not completely resolved. In reptiles, CP is often genetically based and associated with alternative behavioural strategies, mainly in males for most cases. However, female colour morphs also display alternative reproductive strategies associated with behavioural and physiological traits, which may contribute to maintain CP in the population. Both sexes of the common wall lizard (Podarcis muralis) show three pure colour morphs, white, yellow and red. Here, we looked for the effects of male and female colour morphs on fitness traits of captive-breeding pairs. All yellow-throated females laid clutches of many small eggs and produced many light offspring, behaving as r-strategists, whereas white-throated females laid clutches of few large eggs and produced few heavy offspring, behaving as K-strategists. Red-throated females adopted a conditional Kr-strategy depending on their size/age. These basic female strategies were modulated in relation to mate morph: white females had the best fitness gain in terms of viable offspring when mated to red males; mating between yellow morphs yielded a greater breeding success than all other morph crosses, but also lighter offspring; finally, red females produced heavy progeny when paired with red or white males, and light offspring in pair with yellow males. Thus, correlation between CP and traits relevant to fitness combined with non-random mating, either assortative or disassortative, could increase the potential for CP to contribute to divergent evolution in the common wall lizard.  相似文献   

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Behcet’s disease (BD) with arthritis is often confused with seronegative arthritis (SNA) because of shared clinical symptoms and the lack of definitive biomarkers for BD. To investigate possible metabolic patterns and potential biomarkers of BD with arthritis, metabolomic profiling of synovial fluid (SF) from 6 patients with BD with arthritis and 18 patients with SNA was performed using gas chromatography/time-of-flight mass spectrometry in conjunction with univariate and multivariate statistical analyses. A total of 123 metabolites were identified from samples. Orthogonal partial least square-discriminant analysis showed clear discrimination between BD with arthritis and SNA. A set of 11 metabolites were identified as potential biomarkers for BD using variable importance for projection values and the Wilcoxon-Mann-Whitney test. Compared with SNA, BD with arthritis exhibited relatively high levels of glutamate, valine, citramalate, leucine, methionine sulfoxide, glycerate, phosphate, lysine, isoleucine, urea, and citrulline. There were two markers identified, elevated methionine sulfoxide and citrulline, that were associated with increased oxidative stress, providing a potential link to BD-associated neutrophil hyperactivity. Glutamate, citramalate, and valine were selected and validated as putative biomarkers for BD with arthritis (sensitivity, 100%; specificity, 61.1%). This is the first report to present potential biomarkers from SF for discriminating BD with arthritis from SNA. The metabolomics of SF may be helpful in searching for potential biomarkers and elucidating the clinicopathogenesis of BD with arthritis.  相似文献   

4.
Molecular neuroimaging based on annihilation radiation tomographic (ART) techniques such as positron emission tomography (PET), in conjunction with related biomarkers in plasma and cerebrospinal fluid (CSF), are proving valuable in the early and differential diagnosis of Alzheimer's disease (AD). With the advent of new therapeutic strategies aimed at reducing beta-amyloid (Abeta) burden in the brain to potentially prevent or delay functional and irreversible cognitive loss, there is increased interest in developing agents that allow assessment of Abeta burden in vivo. Abeta burden as assessed by molecular imaging matches histopathological reports of Abeta plaque distribution in aging and dementia and appears more accurate than FDG for the diagnosis of AD. Abeta imaging is also a very powerful tool in the differential diagnosis of AD from fronto-temporal dementia (FTD). Although Abeta burden as assessed by PET does not correlate with measures of cognitive decline in AD, it does correlate with memory impairment and rate of memory decline in mild cognitive impairment (MCI) and healthy older subjects. Approximately 30% of asymptomatic controls present cortical (11)C-PiB retention. These observations suggest that Abeta deposition is not part of normal ageing, supporting the hypothesis that Abeta deposition occurs well before the onset of symptoms and is likely to represent preclinical AD. Further longitudinal observations are required to confirm this hypothesis and to better elucidate the role of Abeta deposition in the course of Alzheimer's disease.  相似文献   

5.
Direct molecular-genetic analysis of the region containing CAG and CCG repeats of the IT15 gene from 37 patients with the clinical diagnosis of Huntington’s chorea was carried out. The allele with the expansion of CAG repeats in the state of heterozygosity was found in 33 patients; DNA analysis did not confirm a clinical diagnosis in four cases. Twenty probable asymptomatic carriers were examined; 11 of them inherited a mutant chromosome. A disequilibrium in the linkage between the (CGG)10 allele and the alleles with the expansion of CAG repeats in the IT15 gene in a group of patients from Ukraine was found. Significant differences in character of instability of CAG repeats that depends on paternal or maternal inheritance were revealed. The genetic factors that are associated with age variability of onset of the disease were studied.  相似文献   

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The aim of this study was to develop chitosan-coated and polyplex-loaded liposomes (PLLs) containing DNA vaccine for Peyer’s patch targeting. Plain liposomes carrying plasmid pRc/CMV-HBs were prepared by the reverse-phase evaporation method. Chitosan coating was carried out by incubation of the liposomal suspensions with chitosan solution. Main lipid components of liposomes were phosphatidylcholine/cholesterol. Sodium deoxycholate and dicetyl phosphate were used as negative charge inducers. The zeta potentials of plain liposomes were strongly affected by the pH of the medium. Coating with chitosan variably increased the surface charges of the liposomes. To increase the zeta potential and stability of the liposome, chitosan was also used as a DNA condensing agent to form a polyplex. The PLLs were coated with chitosan solution. In vivo study of PLLs was carried out in comparison with chitosan-coated liposomes using plasmid encoding green fluorescence protein as a reporter. A single dose of plasmid equal to 100 μg was intragastrically inoculated into BALB/c mice. The expression of green fluorescence protein (GFP) was detected after 24 h using a confocal laser scanning microscope. The signal of GFP was obtained from positively charged chitosan-coated liposomes but found only at the upper part of duodenum. With chitosan-coated PLL540, the signal of GFP was found throughout the intestine. Chitosan-coated PLL demonstrated a higher potential to deliver the DNA to the distal intestine than the chitosan-coated liposomes due to the increase in permanent positive surface charges and the decreased enzymatic degradation.  相似文献   

9.
This cross-sectional study aimed to identify where dogs with negative antibody tests to canine parvovirus (CPV) and canine distemper virus (CDV) originated when entering a community shelter, using a commercially available ELISA antibody test and Geographic Information Systems mapping. Of 2745 canines entering during a three-month period, 1056 test results were obtained. Dogs or puppies weighing over 2 lb were eligible if they could be humanely, nonchemically restrained for phlebotomy. Age and minor health issues weren't exclusions. Dogs were excluded if trained personnel were concerned health would be compromised by phlebotomy. Blood samples were collected within 24 hours of entry. Four hundred and twenty-seven (40%) dogs had positive antibody test results for both viruses, 422 (40%) were positive for CPV, 37 (4%) were positive for CDV, and 170 (16%) were negative for both. Mapping revealed geographic patterns for dogs with negative antibody tests. This shelter admitted dogs with negative CPV and/or CDV antibody tests from defined community areas. Targeting vaccination efforts in communities to areas where dogs with negative antibody tests originate could be an effective wellness strategy.  相似文献   

10.
United Nations General Assembly Resolution 61/105 on sustainable fisheries (UNGA 2007) establishes three difficult questions for participants in high-seas bottom fisheries to answer: 1) Where are vulnerable marine systems (VMEs) likely to occur?; 2) What is the likelihood of fisheries interaction with these VMEs?; and 3) What might qualify as adequate conservation and management measures to prevent significant adverse impacts? This paper develops an approach to answering these questions for bottom trawling activities in the Convention Area of the South Pacific Regional Fisheries Management Organisation (SPRFMO) within a quantitative risk assessment and cost : benefit analysis framework. The predicted distribution of deep-sea corals from habitat suitability models is used to answer the first question. Distribution of historical bottom trawl effort is used to answer the second, with estimates of seabed areas swept by bottom trawlers being used to develop discounting factors for reduced biodiversity in previously fished areas. These are used in a quantitative ecological risk assessment approach to guide spatial protection planning to address the third question. The coral VME likelihood (average, discounted, predicted coral habitat suitability) of existing spatial closures implemented by New Zealand within the SPRFMO area is evaluated. Historical catch is used as a measure of cost to industry in a cost : benefit analysis of alternative spatial closure scenarios. Results indicate that current closures within the New Zealand SPRFMO area bottom trawl footprint are suboptimal for protection of VMEs. Examples of alternative trawl closure scenarios are provided to illustrate how the approach could be used to optimise protection of VMEs under chosen management objectives, balancing protection of VMEs against economic loss to commercial fishers from closure of historically fished areas.  相似文献   

11.

Background

QUADOMICS is an adaptation of QUADAS (a quality assessment tool for use in systematic reviews of diagnostic accuracy studies), which takes into account the particular challenges presented by ‘-omics’ based technologies. Our primary objective was to evaluate the applicability and consistency of QUADOMICS. Subsequently we evaluated and describe the methodological quality of a sample of recently published studies using the tool.

Methodology/Principal Findings

45‘-omics’- based diagnostic studies were identified by systematic search of Pubmed using suitable MeSH terms (“Genomics”, “Sensitivity and specificity”, “Diagnosis”). Three investigators independently assessed the quality of the articles using QUADOMICS and met to compare observations and generate a consensus. Consistency and applicability was assessed by comparing each reviewer''s original rating with the consensus. Methodological quality was described using the consensus rating. Agreement was above 80% for all three reviewers. Four items presented difficulties with application, mostly due to the lack of a clearly defined gold standard. Methodological quality of our sample was poor; studies met roughly half of the applied criteria (mean ± sd, 54.7±18.4%). Few studies were carried out in a population that mirrored the clinical situation in which the test would be used in practice, (6, 13.3%); none described patient recruitment sufficiently; and less than half described clinical and physiological factors that might influence the biomarker profile (20, 44.4%).

Conclusions

The QUADOMICS tool can consistently be applied to diagnostic ‘-omics’ studies presently published in biomedical journals. A substantial proportion of reports in this research field fail to address design issues that are fundamental to make inferences relevant for patient care.  相似文献   

12.
Discrimination of and memory for others’ generous and selfish behaviors could be adaptive abilities in social animals. Dogs have seemingly expressed such skills in both direct and indirect interactions with humans. However, recent studies suggest that their capacity may rely on cues other than people’s individual characteristics, such as the place where the person stands. Thus, the conditions under which dogs recognize individual humans when solving cooperative tasks still remains unclear. With the aim of contributing to this problem, we made dogs interact with two human experimenters, one generous (pointed towards the food, gave ostensive cues, and allowed the dog to eat it) and the other selfish (pointed towards the food, but ate it before the dog could have it). Then subjects could choose between them (studies 1-3). In study 1, dogs took several training trials to learn the discrimination between the generous and the selfish experimenters when both were of the same gender. In study 2, the discrimination was learned faster when the experimenters were of different gender as evidenced both by dogs’ latencies to approach the bowl in training trials as well as by their choices in preference tests. Nevertheless, dogs did not get confused by gender when the experimenters were changed in between the training and the choice phase in study 3. We conclude that dogs spontaneously used human gender as a cue to discriminate between more and less cooperative experimenters. They also relied on some other personal feature which let them avoid being confused by gender when demonstrators were changed. We discuss these results in terms of dogs’ ability to recognize individuals and the potential advantage of this skill for their lives in human environments.  相似文献   

13.
Human selection for high crop yield under water-limited conditions should have led modern cereal cultivars to invest less in root biomass, be it unconsciously. To test this hypothesis we conducted a pot experiment with two spring wheat cultivars, one old and one modern, both widely grown in the semi-arid regions of China. Using the replacement series method introduced by de Wit, we showed that the older landrace (Monkhead) was significantly more competitive than the more-modern cultivar (92-46). However, when grown in pure stand, old Monkhead had grown root biomass 3.5 times modern 92-46, whereas modern 92-46 gained a 20% higher grain yield. We also found modern 92-46 significantly increased root biomass per plant and root allocation (i.e., root biomass/total individual biomass) as its frequency in mixtures decreased, whereas old Monkhead did not respond in a similar way. This result suggests that the roots of modern cultivars may have gained an ability to recognize neighboring root systems and show more plastic self-restraining response to intra-cultivar competition.  相似文献   

14.
Background

Conservative treatment in the Scheuermann’s kyphosis obtain, during skeletal growth, remodelling of the deformed vertebras. In a previous paper on Scheuermann’s kyphosis, we have studied the geometry variations of all vertebrae included in the curve, before and after the treatment.

The purpose of this study was to confirm the effectiveness of conservative treatment in Scheuermann’s kyphosis and was to evaluate and compare the variation of the vertebral geometry with the curve trend in Cobb degrees, before and after conservative treatment.

Methods

From a consecutive series of patients, we selected 90 patients with thoracic Scheuermann’s kyphosis, treated using anti-gravity brace: 59 male, 31 female. The mean age at the beginning of the treatment was 14 years.

Radiographical measurements were performed on radiographs from a lateral projection, at the beginning (t1) and at the end of the treatment (t5). Vertebral geometry modifications at t1 and t5 were analysed according to the following parameters and evaluated by three independent observers: Anterior wedging angle (ALFA) of the apex vertebra and Posterior wall inclination (APOS) of the limiting lower vertebra. The curve was measured in Cobb degrees.

Results

The results from our study showed that of the 90 patients with a thoracic curve mean value of Cobb degrees was 57.8 ± 6.0 SD at t1 and 41.3 ± 5.6 SD at t5. The differences between t1(angle at baseline) and t5 (end of treatment) were calculated for Cobb, ALFA and APOS angle and were respectively −16.4 ± 4.5, −6.4 ± 1.4 and −2.7 ± 1.2; tested with paired t-test were significative (p < 0.01). The results of the regression analysis to test the relationship between the three measures for the kyphosis (Cobb degree, ALFA and APOS) showed that the best association was between Cobb t5 and ALFA t5 (p < 0.01) and Cobb t1 and APOS t1 (p < 0.01). No significative association was found between the difference between ALFA and APOS.

Conclusion

We sustain that using new parameters to study vertebral remodelling allows us to reach a better comprehension of Scheuermann spine response to anti-gravity brace treatment. Furthermore, the evaluation of the ALFA angle of the apex vertebra confirms to be more reliable than Cobb’s angle because it cannot be affected by the radiological position.

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15.
We have sequenced the entire (89 exons) open reading frame of the LRP gene in 12 cases of Alzheimer’s disease (AD) from Northern France. We have found no novel changes but confirm the occurrence of a polymorphism in exon 6 of the gene (A216V). This polymorphism is rare (2.8% of controls) and is in linkage equilibrium with previously reported polymorphisms. The V216 allele is negatively associated with the disease in a large case-controlled series. These data suggest that the LRP receptor may be involved in the pathobiology of AD, but the association that we report here cannot explain the previously reported genetic data implicating the LRP gene in AD. If the LRP gene is a major site of genetic variability leading to AD, there must be other biologically relevant variability in promoter or other regulatory elements of this large gene. Received: 28 December 1998 / Accepted: 1 March 1999  相似文献   

16.
Experimental radiobiology represented a long-standing priority for the U.S. Atomic Energy Commission (AEC), but organizational issues initially impeded the laboratory progress of this government-funded work: who would direct such interdisciplinary investigations and how? And should the AEC support basic research or only mission-oriented projects? Alexander Hollaender’s vision for biology in the post-war world guided AEC initiatives at Oak Ridge, where he created and presided over the Division of Biology for nearly two decades (1947–1966). Hollaender’s scheme, at once entrepreneurial and system-oriented, made good use of the unique resources provided by the AEC and by Oak Ridge’s national laboratory setting, while at the same time it restructured wartime research practices to better reflect biologists’ own priorities. Because Hollaender offered many academic experimental biologists a way of envisioning military-related patronage as integral – rather than antithetical – to their professional identities, his work provides an important lens through which to examine the early post-war intellectual and institutional development of radiobiology.  相似文献   

17.
Structural MR image (MRI) and 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET) have been widely employed in diagnosis of both Alzheimer’s disease (AD) and mild cognitive impairment (MCI) pathology, which has led to the development of methods to distinguish AD and MCI from normal controls (NC). Synaptic dysfunction leads to a reduction in the rate of metabolism of glucose in the brain and is thought to represent AD progression. FDG-PET has the unique ability to estimate glucose metabolism, providing information on the distribution of hypometabolism. In addition, patients with AD exhibit significant neuronal loss in cerebral regions, and previous AD research has shown that structural MRI can be used to sensitively measure cortical atrophy. In this paper, we introduced a new method to discriminate AD from NC based on complementary information obtained by FDG and MRI. For accurate classification, surface-based features were employed and 12 predefined regions were selected from previous studies based on both MRI and FDG-PET. Partial least square linear discriminant analysis was employed for making diagnoses. We obtained 93.6% classification accuracy, 90.1% sensitivity, and 96.5% specificity in discriminating AD from NC. The classification scheme had an accuracy of 76.5% and sensitivity and specificity of 46.5% and 89.6%, respectively, for discriminating MCI from AD. Our method exhibited a superior classification performance compared with single modal approaches and yielded parallel accuracy to previous multimodal classification studies using MRI and FDG-PET.  相似文献   

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Background

The QuantiFERON®-TB Gold In-Tube test (QFT-GIT) detects Mycobacterium tuberculosis (Mtb) infection by measuring release of interferon gamma (IFN-γ) when T-cells (in heparinized whole blood) are stimulated with specific Mtb antigens. The amount of IFN-γ is determined by enzyme-linked immunosorbent assay (ELISA). Automation of the ELISA method may reduce variability. To assess the impact of ELISA automation, we compared QFT-GIT results and variability when ELISAs were performed manually and with automation.

Methods

Blood was collected into two sets of QFT-GIT tubes and processed at the same time. For each set, IFN-γ was measured in automated and manual ELISAs. Variability in interpretations and IFN-γ measurements was assessed between automated (A1 vs. A2) and manual (M1 vs. M2) ELISAs. Variability in IFN-γ measurements was also assessed on separate groups stratified by the mean of the four ELISAs.

Results

Subjects (N = 146) had two automated and two manual ELISAs completed. Overall, interpretations were discordant for 16 (11%) subjects. Excluding one subject with indeterminate results, 7 (4.8%) subjects had discordant automated interpretations and 10 (6.9%) subjects had discordant manual interpretations (p = 0.17). Quantitative variability was not uniform; within-subject variability was greater with higher IFN-γ measurements and with manual ELISAs. For subjects with mean TB Responses ±0.25 IU/mL of the 0.35 IU/mL cutoff, the within-subject standard deviation for two manual tests was 0.27 (CI95 = 0.22–0.37) IU/mL vs. 0.09 (CI95 = 0.07–0.12) IU/mL for two automated tests.

Conclusion

QFT-GIT ELISA automation may reduce variability near the test cutoff. Methodological differences should be considered when interpreting and using IFN-γ release assays (IGRAs).  相似文献   

20.

Background

We estimated the occurrence rate of the booster phenomenon by using an intradermal test with 43 kDa glycoprotein in an endemic area of paracoccidioidomycosis in the central-west region of Brazil.

Methods

Individuals who had a negative result on a survey performed by using an intradermal test with 43 kDa glycoprotein in an endemic area of paracoccidioidomycosis underwent a second intradermal test after 10–15 days to determine the presence or absence of the booster phenomenon. Statistical analyses were performed using the Chi-square test, Chi-square for linear trend test, Student’s t test, and binomial test; p < 0.05 was considered significant.

Results

For the first time, we reported the occurrence of the booster phenomenon to an intradermal reaction caused by 43 kDa glycoprotein at a rate of 5.8–8.4%, depending on the test’s cutoff point. This suggests that a cutoff point should be considered for the booster phenomenon in intradermal tests with 43 kDa glycoprotein: a difference of 6–7 mm between readings according to the first and second tests, depending on the purpose of the evaluation.

Conclusion

The results indicate that the prevalence of paracoccidioidal infection in endemic areas is underestimated, as the booster phenomenon has not been considered in epidemiological surveys for this infection.
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