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101.
Mircea G. Hidalgo-Mihart Lisette Cantú-Salazar Alberto González-Romero Carlos A. López-González 《Journal of Biogeography》2004,31(12):2025-2038
Aim Coyote (Canis latrans) distribution in Mexico and Central America has expanded recently reaching the Yucatan peninsula, Belize and Panama, probably promoted by deforestation of tropical areas. Historically, the southern distribution of coyotes prior to European settlement in America was described as reaching only as far south as central Mexico and that introduction of livestock favoured migration of coyotes to southern Mexico and Central America. However, coyote fossil records in Central America and Yucatan, as well as observational records of travellers during the sixteenth century suggest that the coyote's arrival to the region was earlier. Because of the uncertainty of past coyote distribution and the possible economic and ecological impacts due to recent range expansion, the objectives of this study were to confirm if paleontological and historical evidence support the hypothesis that the southernmost limit of coyote distribution before the arrival of European settlers was the centre of Mexico, to discuss the possible factors that have influenced historical shifts in coyote distribution, and to model the present distribution of the coyote in Mexico and Central America, determining the areas where they could invade in the near future. Location The research area comprises continental Mexico and the Central American Isthmus countries: Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. Methods The historical distribution (Pleistocene–Early Holocene, Pre‐Columbian, sixteenth to nineteenth centuries and twentieth century) was established from coyote records obtained from museum collections and specialized literature. Present coyote distribution for Mexico and Central America was modelled using the Genetic Algorithms for Rule‐set Prediction (GARP). Results Historical coyote records show that this species was distributed in southern Mexico and Central America during the Pleistocene–Early Holocene, the Pre‐Columbian period, and during the arrival of Europeans in the sixteenth century. Coyote records indicate a continuous range expansion during the twentieth century. Historical advance and regression of tropical forests in southern Mexico and Central America produced by natural and human events such as climatic changes and variation in human densities could help us understand the historical coyote distribution. The modelled present‐day coyote distribution included the north of Belize, the north of Panama, the north of the Yucatan Peninsula and a corridor on the Gulf costal plain of Campeche in Mexico. Also, the model predicted a region north of the Darien in southern Panama as appropriate for the presence of coyotes, although they have not been detected there so far. Main conclusion Coyote records in southern Mexico and Central America during the Pleistocene–Early Holocene, the Pre‐Columbian period, and early arrival of European settlers to the area indicated that coyotes were probably already present there and did not recently disperse from the north of Mexico to the south due to livestock introduction. 相似文献
102.
Lisette Cantú-Salazar Mircea G. Hidalgo-Mihart Carlos A. López-González Alberto González-Romero 《Biotropica》2009,41(3):347-353
Dry season den use by the pygmy spotted skunk Spilogale pygmaea , an endemic and threatened species of western Mexico, was evaluated at the micro and macrohabitat level, in the tropical deciduous forest of Chamela, Jalisco, Mexico. During the dry seasons of 1997, 1998, and 2000, 79 skunk den sites (29 for females and 50 males) were located using Radiotelemetry. Dens were underground excavations with one to five access points, located mostly on open ground or under live or dead trees. Skunks exhibited a continued reuse of dens but evidence of simultaneous occupation by two or more skunks was not found. Microhabitat den-site analysis showed that skunks showed flexibility and individual variation in usage of the microhabitat surrounding den sites inside the forest. Macrohabitat den-site analysis showed that skunks were not selecting either tropical deciduous or tropical semideciduous forest; however, no dens were located outside the forest in transformed habitats, strengthening the hypothesis of the association of this species with the tropical deciduous forests on the Pacific coast of Mexico. The current deforestation rates of the tropical deciduous forest in the coast of Jalisco could be reducing the potential den sites for pygmy spotted skunks and exposing them to adverse environmental conditions and predation. 相似文献
103.
Sarlus H Höglund CO Karshikoff B Wang X Lekander M Schultzberg M Oprica M 《Journal of cellular and molecular medicine》2012,16(10):2401-2412
Despite the existing knowledge regarding the neuropathology of Alzheimer's disease (AD), the cause of sporadic forms of the disease is unknown. It has been suggested that systemic inflammation may have a role, but the exact mechanisms through which inflammatory processes influence the pathogenesis and progress of AD are not obvious. Allergy is a chronic inflammatory disease affecting more than 20% of the Western population, but the effects of allergic conditions on brain functions are largely unknown. The aim of this study was to investigate whether or not chronic peripheral inflammation associated with allergy affects the expression of AD-related proteins and inflammatory markers in the brain. On the basis of previously described models for allergy in mice we developed a model of chronic airway allergy in mouse, with ovalbumin as allergen. The validity of the chronic allergy model was confirmed by a consistent and reproducible eosinophilia in the bronchoalveolar lavage (BAL) fluid of allergic animals. Allergic mice were shown to have increased brain levels of both immunoglobulin (Ig) G and IgE with a widespread distribution. Allergy was also found to increase phosphorylation of tau protein in the brain. The present data support the notion that allergy-dependent chronic peripheral inflammation modifies the brain inflammatory status, and influences phosphorylation of an AD-related protein, indicating that allergy may be yet another factor to be considered for the development and/or progression of neurodegenerative diseases such as AD. 相似文献
104.
Ann L Griffen Clifford J Beall James H Campbell Noah D Firestone Purnima S Kumar Zamin K Yang Mircea Podar Eugene J Leys 《The ISME journal》2012,6(6):1176-1185
Periodontitis has a polymicrobial etiology within the framework of a complex microbial ecosystem. With advances in sequencing technologies, comprehensive studies to elucidate bacterial community differences have recently become possible. We used 454 sequencing of 16S rRNA genes to compare subgingival bacterial communities from 29 periodontally healthy controls and 29 subjects with chronic periodontitis. Amplicons from both the V1-2 and V4 regions of the 16S gene were sequenced, yielding 1 393 579 sequences. They were identified by BLAST against a curated oral 16S database, and mapped to 16 phyla, 106 genera, and 596 species. 81% of sequences could be mapped to cultivated species. Differences between health- and periodontitis-associated bacterial communities were observed at all phylogenetic levels, and UniFrac and principal coordinates analysis showed distinct community profiles in health and disease. Community diversity was higher in disease, and 123 species were identified that were significantly more abundant in disease, and 53 in health. Spirochaetes, Synergistetes and Bacteroidetes were more abundant in disease, whereas the Proteobacteria were found at higher levels in healthy controls. Within the phylum Firmicutes, the class Bacilli was health-associated, whereas the Clostridia, Negativicutes and Erysipelotrichia were associated with disease. These results implicate a number of taxa that will be targets for future research. Some, such as Filifactor alocis and many Spirochetes were represented by a large fraction of sequences as compared with previously identified targets. Elucidation of these differences in community composition provides a basis for further understanding the pathogenesis of periodontitis. 相似文献
105.
SD Brown M Podar DM Klingeman CM Johnson ZK Yang SM Utturkar ML Land JJ Mosher RA Hurt TJ Phelps AV Palumbo AP Arkin TC Hazen DA Elias 《Journal of bacteriology》2012,194(18):5147-5148
Pelosinus fermentans 16S rRNA gene sequences have been reported from diverse geographical sites since the recent isolation of the type strain. We present the genome sequence of the P. fermentans type strain R7 (DSM 17108) and genome sequences for two new strains with different abilities to reduce iron, chromate, and uranium. 相似文献
106.
George Han Luis R. Martinez Mircea Radu Mihu Adam J. Friedman Joel M. Friedman Joshua D. Nosanchuk 《PloS one》2009,4(11)
Staphylococcus aureus (SA) is a leading cause of a diverse spectrum of bacterial diseases, including abscesses. Nitric oxide (NO) is a critical component of the natural host defense against pathogens such as SA, but its therapeutic applications have been limited by a lack of effective delivery options. We tested the efficacy of a NO-releasing nanoparticle system (NO-np) in methicillin-resistant SA (MRSA) abscesses in mice. The results show that the NO-np exert antimicrobial activity against MRSA in vitro and in abscesses. Topical or intradermal NO-np treatment of abscesses reduces the involved area and bacterial load while improving skin architecture. Notably, we evaluated pro- and anti-inflammatory cytokines that are involved in immunomodulation and wound healing, revealing that NO-np lead to a reduction in angiogenesis preventing bacterial dissemination from abscesses. These data suggest that NO-np may be useful therapeutics for microbial abscesses. 相似文献
107.
Gabriel Tatu-Chitoiu Mircea Cinteza Maria Dorobantu Mariana Udeanu Olivia Manfrini Carmine Pizzi Marius Vintila Dominic D. Ionescu Elvira Craiu Daniel Burghina Raffaele Bugiardini 《CMAJ》2009,180(12):1207-1213
Background
We describe the clinical characteristics, treatments and in-hospital case-fatality rates in an unselected population of patients admitted for acute myocardial infarction.Methods
From January 2000 to June 2007, we tracked consecutive patients who were admitted to 7 tertiary referral and 21 county hospitals in Romania for medical treatment of ST-segment elevation acute myocardial infarction. These patients were enrolled in the Romanian Registry for ST-segment Elevation Myocardial Infarction. For this prospective study, we collected data on demographic characteristics, cardiovascular risk factors, various aspects of treatment for myocardial infarction, and in-hospital death.Results
The 9186 patients in the study group had a mean age of 63.8 years. The median time from onset of symptoms to thrombolysis was 230 (interquartile range 120–510) minutes. Of the 9186 patients, 4986 (54.3%) had hypertension, 1974 (21.5%) had diabetes mellitus, 3545 (38.6%) had lipid disorders and 4653 (50.7%) were smokers. The in-hospital mortality rate was 12.7% (1170 deaths). The study group consisted of 2893 women and 6293 men. The women were older than the men and had higher rates of hypertension and diabetes mellitus but were less likely to be smokers. A smaller proportion of women than men presented within 2 hours after onset of symptoms (23.1% v. 34.4%, p < 0.001). Smaller proportions of women received thrombolytics (40.8% v. 53.5%, p < 0.001), anticoagulants (93.4% v. 95.2%; p = 0.001), antiplatelet agents (88.3% v. 91.2%, p < 0.001) and primary percutaneous coronary interventions (1.5% v. 2.2%, p = 0.030). The risk of in-hospital death was greater for women, even after adjustment for confounders (odds ratio 1.33, 95% confidence interval 1.13–1.56; p < 0.001).Interpretation
The rates of reperfusion therapy for patients with acute myocardial infarction were low, and in-hospital case-fatality rates were high in this study. Excess in-hospital mortality was more pronounced among women.During the past 10 years, the health of people in Eastern Europe and the former Soviet Union has undergone changes very different from the health patterns seen in their Western counterparts. For example, mortality from cardiovascular disease has been decreasing continuously in the United States and many Western European countries, but it has increased or remained unchanged in many of the states of Eastern Europe.1Analysis of this phenomenon has been hindered by insufficient information. The World Health Organization’s MONICA project for monitoring cardiovascular mortality and risk factors considered only 6 Eastern European countries: Russia, Yugoslavia, Poland, Czechoslovakia, Hungary and the former East Germany.2 In geographic terms, Romania is the largest country in southeastern Europe, with a large population and substantial natural resources,3 but in some ways it is a “forgotten country.” Few studies evaluating risks for cardiovascular disease have included Romania. Only 4 trials examining ST-segment elevation myocardial infarction have enrolled patients from Romania,4–6 and the numbers of patients were too few for reliable subgroup analysis.Our aim was to investigate clinical characteristics, treatments and case fatality rates in an unselected population of patients admitted to hospital in Romania for ST-segment elevation myocardial infarction. In a secondary analysis, we analyzed sex differences in relation to treatment and outcome. 相似文献108.
Mulhbacher J Ispas-Szabo P Ouellet M Alex S Mateescu MA 《International journal of biological macromolecules》2006,40(1):9-14
Acetate (Ac-), aminoethyl (AE-) and carboxymethyl (CM-)derivatives of cross-linked high amylose starch (HASCL-6) were previously shown to control, over more than 20h, the release of drugs from highly loaded (up to 60% drug) monolithic tablets. It was now of interest to evaluate their mucoadhesive characteristics in view of further utilization in buccal or vaginal transmucosal delivery. The present study shows that ionic AE-HASCL-6 and CM-HASCL-6 derivatives exhibit higher mucoadhesive properties than neutral HASCL-6 and Ac-HASCL-6, suggesting that the ionic groups introduced on cross-linked starch chains play a role in the bioadhesion process. The adhesiveness seemed related to capillary attraction forces. Surface adhesion parameters were calculated for slabs based on the mentioned polymers and corroborated with their swelling behavior at various pH changes. The positively charged AE-derivatives presented a higher adhesion at acidic pH, being thus recommended for vaginal delivery, whereas the negatively charged derivatives (CM-HASCL-6) exhibited a better adhesion at neutral pH, being thus more appropriate for buccal delivery. 相似文献
109.
Julia Avram Felicia Rodica Balteş Mircea Miclea Andrei C. Miu 《Applied psychophysiology and biofeedback》2010,35(4):285-292
Electroencephalography (EEG) has been extensively used in studies of the frontal asymmetry of emotion and motivation. This
study investigated the midfrontal EEG activation, heart rate and skin conductance during an emotional face analog of the Stroop
task, in anxious and non-anxious participants. In this task, the participants were asked to identify the expression of calm,
fearful and happy faces that had either a congruent or incongruent emotion name written across them. Anxious participants
displayed a cognitive bias characterized by facilitated attentional engagement with fearful faces. Fearful face trials induced
greater relative right frontal activation, whereas happy face trials induced greater relative left frontal activation. Moreover,
anxiety specifically modulated the magnitude of the right frontal activation to fearful faces, which also correlated with
the cognitive bias. Therefore, these results show that frontal EEG activation asymmetry reflects the bias toward facilitated
processing of fearful faces in anxiety. 相似文献
110.
Lance D Miller Jennifer J Mosher Amudhan Venkateswaran Zamin K Yang Anthony V Palumbo Tommy J Phelps Mircea Podar Christopher W Schadt Martin Keller 《BMC microbiology》2010,10(1):149