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81.
Parasitology Research - Dogs are important hosts and reservoirs of leishmaniasis, a disease caused by protozoan parasites from the genus Leishmania, affecting ~12 million people worldwide. The...  相似文献   
82.
In Mexico, the first outbreaks suggestive of the circulation of the porcine epidemic diarrhea virus (PEDV) were identified at the beginning of July 2013. To identify the molecular characteristics of the PEDV Spike (S) gene in Mexico, 116 samples of the intestine and diarrhea of piglets with clinical signs of porcine epidemic diarrhea (PED) were obtained. Samples were collected from 14 farms located in six states of Mexico (Jalisco, Puebla, Sonora, Veracruz, Guanajuato, and Michoacán) from 2013 to 2016. To identify PEDV, we used real-time RT-PCR to discriminate between non-INDEL and INDEL strains. We chose samples according to state and year to characterize the S gene. After amplification of the S gene, the obtained products were sequenced and assembled. The complete amino acid sequences of the spike protein were used to perform an epitope analysis, which was used to determine null mutations in regions SS2, SS6, and 2C10 compared to the sequences of G2. A phylogenetic analysis determined the circulation of G2b and INDEL strains in Mexico. However, several mutations were recorded in the collagenase equivalent (COE) region that were related to the change in polarity and charge of the amino acid residues. The PEDV strain circulating in Jalisco in 2016 has an insertion of three amino acids (232LGL234) and one change in the antigenic site of the COE region, and strains from the years 2015 and 2016 changed the index of the surface probability, which could be related to the re-emergence of disease outbreaks.  相似文献   
83.
Pigeons and doves (Columbiformes) are one of the oldest and most diverse extant lineages of birds. However, the karyotype evolution within Columbiformes remains unclear. To delineate the synteny-conserved segments and karyotypic differences among four Columbidae species, we used chromosome painting from Gallus gallus (GGA, 2n?=?78) and Leucopternis albicollis (LAL, 2n?=?68). Besides that, a set of painting probes for the eared dove, Zenaida auriculata (ZAU, 2n?=?76), was generated from flow-sorted chromosomes. Chromosome painting with GGA and ZAU probes showed conservation of the first ten ancestral pairs in Z. auriculata, Columba livia, and Columbina picui, while in Leptotila verreauxi, fusion of the ancestral chromosomes 6 and 7 was observed. However, LAL probes revealed a complex reorganization of ancestral chromosome 1, involving paracentric and pericentric inversions. Because of the presence of similar intrachromosomal rearrangements in the chromosomes corresponding to GGA1q in the Columbidae and Passeriformes species but without a common origin, these results are consistent with the recent proposal of divergence within Neoaves (Passerea and Columbea). In addition, inversions in chromosome 2 were identified in C. picui and L. verreauxi. Thus, in four species of distinct genera of the Columbidae family, unique chromosomal rearrangements have occurred during karyotype evolution, confirming that despite conservation of the ancestral syntenic groups, these chromosomes have been modified by the occurrence of intrachromosomal rearrangements.  相似文献   
84.
This study explores the impact of illness‐related shame on the quality of social relationships and psychological health in chronic patients. We aimed to examine the roles of fear of receiving compassion from others and experiential avoidance as potential mediators of this relationship. Although some studies have demonstrated the negative impact of chronic illness‐related shame on psychological functioning, the mechanisms that may underlie this link remain understudied. The sample was comprised by 115 college students, which had been diagnosed with at least 1 chronic illness. Participants completed self‐report measures on an online platform. This study's design was cross‐sectional. A path analysis was conducted using structural equation modelling. Results showed that the impact of illness‐related shame on both psychological health (R2 = .45) and the quality of social relationships (R2 = .33) was fully accounted by fear of compassion from others and experiential avoidance. This model revealed an excellent fit. Fear of receiving compassion from others was the main mediator of the illness‐related shame link with the quality of social relationships (β = ?.22). The main mediator of the association between shame‐related chronic illness and psychological health was experiential avoidance (β = ?.21).This study shed light on possible psychological mechanisms linking feelings of shame associated with having a chronic condition and impaired social relationships and mental health. On one hand, resisting feelings of compassion and care from others and, on the other hand, avoiding difficult internal experiences and situations that might trigger them seem to underlie the impact of shame on psychological and social functioning in chronic patients.  相似文献   
85.
This paper deals with the molecular investigation of Waardenburg syndrome (WS) in a sample of 49 clinically diagnosed probands (most from southeastern Brazil), 24 of them having the type 1 (WS1) variant (10 familial and 14 isolated cases) and 25 being affected by the type 2 (WS2) variant (five familial and 20 isolated cases). Sequential Sanger sequencing of all coding exons of PAX3, MITF, EDN3, EDNRB, SOX10 and SNAI2 genes, followed by CNV detection by MLPA of PAX3, MITF and SOX10 genes in selected cases revealed many novel pathogenic variants. Molecular screening, performed in all patients, revealed 19 causative variants (19/49?=?38.8%), six of them being large whole-exon deletions detected by MLPA, seven (four missense and three nonsense substitutions) resulting from single nucleotide substitutions (SNV), and six representing small indels. A pair of dizygotic affected female twins presented the c.430delC variant in SOX10, but the mutation, imputed to gonadal mosaicism, was not found in their unaffected parents. At least 10 novel causative mutations, described in this paper, were found in this Brazilian sample. Copy-number-variation detected by MLPA identified the causative mutation in 12.2% of our cases, corresponding to 31.6% of all causative mutations. In the majority of cases, the deletions were sporadic, since they were not present in the parents of isolated cases. Our results, as a whole, reinforce the fact that the screening of copy-number-variants by MLPA is a powerful tool to identify the molecular cause in WS patients.  相似文献   
86.
This longitudinal study aimed at determining predicting variables for middle and long-term psychological disturbance due pre-symptomatic testing (PST) for two late-onset neurological diseases, Huntington disease (HD) and TTR (transthyretin protein) familial amyloid polyneuropathy (FAP) Val30Met (now classified as Val50Met). 196 clinical records of persons who performed PST at least three years ago and answered to the two stages of evaluation (before PST and least 3 years after disclosure of results) were analysed. For this purpose, regression analysis was performed, showing that the Positive Symptom Distress Index (PSDI), psychoticism, somatization and paranoid ideation dimensions assume predictive value in the middle and long-term impact for total anxiety and PSDI. The result of PST was not a relevant predictor. The application of an evaluation instrument of various psychopathological dimensions played a fundamental role in the detection of clinical situations that may arise several years later after PST. Attention should be paid to providing psychological support to persons at-risk who, at the pre-test phase, present some psychopathology indices before pursuing with genetic testing.  相似文献   
87.
The Mediterranean Basin is a climate and biodiversity hot spot, and climate change threatens agro-ecosystems such as olive, an ancient drought-tolerant crop of considerable ecological and socioeconomic importance. Climate change will impact the interactions of olive and the obligate olive fruit fly (Bactrocera oleae), and alter the economics of olive culture across the Basin. We estimate the effects of climate change on the dynamics and interaction of olive and the fly using physiologically based demographic models in a geographic information system context as driven by daily climate change scenario weather. A regional climate model that includes fine-scale representation of the effects of topography and the influence of the Mediterranean Sea on regional climate was used to scale the global climate data. The system model for olive/olive fly was used as the production function in our economic analysis, replacing the commonly used production-damage control function. Climate warming will affect olive yield and fly infestation levels across the Basin, resulting in economic winners and losers at the local and regional scales. At the local scale, profitability of small olive farms in many marginal areas of Europe and elsewhere in the Basin will decrease, leading to increased abandonment. These marginal farms are critical to conserving soil, maintaining biodiversity, and reducing fire risk in these areas. Our fine-scale bioeconomic approach provides a realistic prototype for assessing climate change impacts in other Mediterranean agro-ecosystems facing extant and new invasive pests.The Mediterranean Basin is a climate change (1) and biodiversity (2) hot spot where substantial warming is predicted in the next few decades (3). A 2 °C increase in average temperature is a widely used metric for assessing risks associated with global warming and as a policy reference, and this level of warming will likely occur in the Basin between 2030 and 2060 (4) with unknown biological and economic impact on major crop systems. Small differences in average climate warming are predicted for the Basin by A1B and higher greenhouse-gases (GHG) forcing scenarios within the 2050 time horizon (5).A major agro-ecosystem in the Basin is olive (Olea europaea L.), an ancient ubiquitous crop of considerable socioeconomic importance (6). A detailed review of methods used to assess the impact of weather and of climate change on the olive system is given in SI Appendix. Most of the crop is used to produce olive oil, with Basin countries producing 97% of the world supply (International Olive Council, www.internationaloliveoil.org/). Olive is a long-lived drought-tolerant species limited by frost and high temperatures, and to a lesser extent by low soil fertility and soil water (7). Temperatures <−8.3 °C damage olive and limit its northward distribution, whereas annual rainfall <350 mm y−1 limits its distribution in arid regions. Commercial olive production occurs in areas with >500 mm rainfall y−1 (SI Appendix, Fig. S1). Climate models predict increased temperatures for the Mediterranean Basin in response to increasing [GHG], but only a weak negative trend in precipitation and no trend in evaporation are predicted (8). Growth rates in some plants will increase with [CO2] within their thermal and moisture limits (7, 9), but the response for olive is unknown.Mainstream assessments of climate change impact on agricultural and other ecosystems have omitted trophic interactions (10). Here we include the effects of climate change on olive phenology, growth, and yield, and on the dynamics and impact of its obligate major pest, the olive fruit fly [Bactrocera oleae (Rossi)]. The thermal limits of olive and the fly differ and affect the trophic interactions (11) crucial to estimating the bioeconomic impact of climate change in olive across the Basin.Previous assessments of climate change on heterothermic species have used ecological niche modeling (ENM) approaches that characterize climatically a species’ geographic range based on observed aggregate weather data in areas of its recorded distribution (for olive, see, e.g., ref. 12). ENMs are often used to predict the distribution of the species in response to climate change (13) despite serious deficiencies including the inability to include trophic interactions (14). Moreover, the implicit mathematical and ecological assumptions of ENMs hinder biological interpretation of the results (15).As an alternative we use mechanistic physiologically based demographic models (PBDMs) that explicitly capture the weather-driven biology of interacting species (e.g., ref. 16) and predict the geographic distribution and relative abundance of species across time and space independent of species distribution records using extant and climate change weather scenarios as drivers for the system. The explicit assumptions in PBDMs have heuristic value, and bridge the gap between long run field experiments used to study global change biology and the narrow methodological and conceptual bases of ENM approaches commonly used in macroecology (17, 18). These attributes are essential for assessing the bioeconomic consequences of climate warming on trophic interactions across large landscapes.Linked PBDMs for olive and olive fly in a geographic information system (GIS) context (11) (Fig. 1 and SI Appendix, Fig. S2) are used to estimate the fine-scale ecological and economic impact of climate warming on olive yield and fly infestation across the Basin using baseline daily weather (scenario ) simulated under observed [GHG], and the increasing [GHG] A1B emissions scenario () of the Intergovernmental Panel on Climate Change (IPCC) (Materials and Methods and SI Appendix, SI Materials and Methods).Open in a separate windowFig. 1.Multitrophic biology of the olive/olive fly system. (A) Dry matter flow in olive and to olive fly, and (B) dynamics of olive fly number (see ref. 22).  相似文献   
88.

Background

Characterized as a sudden and temporary loss of consciousness and postural tone, with quick and spontaneous recovery, syncope is caused by an acute reduction of systemic arterial pressure and, therefore, of cerebral blood flow. Unsatisfactory results with the use of drugs allowed the nonpharmacological treatment of neurocardiogenic syncope was contemplated as the first therapeutic option.

Objectives

To compare, in patients with neurocardiogenic syncope, the impact of a moderate intensity aerobic physical training (AFT) and a control intervention on the positivity of head-up tilting test (HUT) and orthostatic tolerance time.

Methods

Were studied 21 patients with a history of recurrent neurocardiogenic syncope and HUT. The patients were randomized into: trained group (TG), n = 11, and control group (CG), n = 10. The TG was submitted to 12 weeks of AFT supervised, in cycle ergometer, and the CG to a control procedure that consisted in 15 minutes of stretching and 15 minutes of light walk.

Results

The TG had a positive effect to physical training, with a significant increase in peak oxygen consumption. The CG did not show any statistically significant change before and after the intervention. After the intervention period, 72.7% of the TG sample had negative results to the HUT, not having syncope in the revaluation.

Conclusion

The program of supervised aerobic physical training for 12 weeks was able to reduce the number of positive HUT, as it was able to increase tolerance time in orthostatic position during the HUT after the intervention period.  相似文献   
89.
Background: Intermittent administration of parathyroid hormone (PTH) promotes new bone formation in patients with osteoporosis and bone fractures. It was shown previously that PTH also reduces periodontitis‐related bone loss. The aim of this study is to evaluate the effect of treatment with PTH on periodontal healing in rats. Methods: Fenestration defects were created at the buccal surface of the distal root of the mandibular first molars, and both periodontal ligament (PDL) and cementum were removed. Animals were then assigned to two groups (eight animals per group): group 1: control, placebo administration; and group 2: test, human PTH (hPTH) 1‐34 administration at a concentration of 40 μg/kg. For both groups, the animals were injected every 2 days, and the animals were sacrificed at 14 and 21 days after surgery. Specimens were harvested and processed for routine decalcified histologic sections. The following parameters were assessed: 1) remaining bone defect extension (RBDE); 2) newly formed bone density (NFBD); 3) total callus area (TCA); 4) osteoclast number (ON) in the callus region; and 5) newly formed dental cementum‐like tissue (NFC). Birefringence of root PDL reattachment was also evaluated. Results: Birefringence analysis showed root PDL reattachment for both groups 21 days after treatment. Intermittent hPTH 1‐34 administration decreased RBDE (P <0.01) and increased NFBD (P <0.01), TCA (P <0.01), area of NFC (P <0.01), and ON in the callus region (P <0.01). Conclusion: Within the limits of the present study, intermittent administration of hPTH 1‐34 led to an enhanced periodontal healing process compared with non‐treated animals.  相似文献   
90.

Introduction

Low-dose weekly methotrexate (MTX) is the mainstay in the therapy of rheumatoid arthritis (RA). It can be given via oral, intramuscular or subcutaneous (SC) route. This study sought to determine the real-world pattern of treatment with SC MTX in Portuguese adult patients with active RA.

Methods

Utilization of Metoject® in Rheumatoid Arthritis (UMAR) was a non-interventional, cohort multicenter study with retrospective data collection. Eligible patients had active RA, at least 18 years of age, and started SC MTX treatment in 2009 or 2010 after failure or intolerance to oral MTX. Data were collected from patient’s clinical records. Both non-parametric and parametric survival methods were used to obtain a detailed understanding of SC MTX treatment duration.

Result

Fifty patients were included, of which only 9 discontinued SC MTX during the study follow-up period. The probability of discontinuation after 1, 2, and 3 years of treatment of SC MTX treatment is expected to be 6.10%, 8.50%, and 23.20%, respectively. The extrapolated median duration of SC MTX using an exponential model was 106.4 months/8.87 years. Mean dose of SC MTX was 18.36 mg. The reasons for treatment discontinuation were occurrence of adverse events in six patients and lack of efficacy in three.

Conclusion

The long treatment duration of SC MTX highlights its excellent tolerability compared to oral MTX, especially concerning the frequent adverse gastrointestinal events of MTX. Furthermore, long MTX treatment duration provides the opportunity to postpone or even avoid expensive therapies with biologics. The results obtained from the UMAR study provide important information for the utilization and public financing of SC MTX in Portugal.
  相似文献   
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