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31.
Edward H. Miller Juan Ignacio Areta Alvaro Jaramillo Santiago Imberti Ricardo Matus 《Ibis》2020,162(3):968-990
We analysed breeding sounds of the two subspecies of South American Snipe Gallinago paraguaiae paraguaiae and Gallinago paraguaiae magellanica to determine whether they might be different species: loud vocalizations given on the ground, and the tail-generated Winnow given in aerial display. Sounds of the two taxa differ qualitatively and quantitatively. Both taxa utter two types of ground call. In G. p. paraguaiae, the calls are bouts of identical sound elements repeated rhythmically and slowly (about five elements per second (Hz)) or rapidly (about 11 Hz). One call of G. p. magellanica is qualitatively similar to those of G. p. paraguaiae but sound elements are repeated more slowly (about 3 Hz). However, its other call type differs strikingly: it is a bout of rhythmically repeated sound couplets, each containing two kinds of sound element. The Winnow of G. p. paraguaiae is a series of sound elements that gradually increase in duration and energy; by contrast, that of G. p. magellanica has two or more kinds of sound element that roughly alternate and are repeated as sets, imparting a stuttering quality. Sounds of the related Puna Snipe (Gallinago andina) resemble but differ quantitatively from those of G. p. paraguaiae. Differences in breeding sounds of G. p. paraguaiae and G. p. magellanica are strong and hold throughout their geographical range. Therefore we suggest that the two taxa be considered different species: G. paraguaiae east of the Andes in much of South America except Patagonia, and G. magellanica in central and southern Chile, Argentina east of the Andes across Patagonia, and Falklands/Malvinas. 相似文献
32.
Acta Biotheoretica - Both physiological and evolutionary criteria of biological individuality are underpinned by the idea that an individual is a functionally integrated whole. However, a precise... 相似文献
33.
Alvaro Osorio Esperanza Ortega Jesús M. Torres Pilar Sanchez Estrella Ruiz-Requena 《Molecular and cellular biochemistry》2013,374(1-2):21-27
The increased vascular calcification, cardiovascular morbidity, and mortality in chronic kidney disease (CKD) patients has been associated with disturbances in mineral-bone metabolism. In order to determine markers of the vascular calcification frequently observed in these patients, blood samples of elderly male and female hemodialysis CKD patients were used to measure serum levels of: osteoprotegerin (OPG), total soluble receptor activator of nuclear factor-κB ligand (sRANKL), and fetuin-A by enzyme immunoassay; tartrate-resistant acid phosphatase (TRACP-5b), and bone-specific alkaline phosphatase (BAP) by immunoenzymometric assay; osteocalcin (OC) by ELISA; iPTH by immunoradiometric assay; 25(OH)D3 and 1,25(OH)2D3, by I125 radioimmunoassay; and calcium and phosphorus by photometric assay. Serum OPG, BAP, iPTH, phosphorus, and OC levels were higher and serum 25(OH)D3, 1,25(OH)2D3, and fetuin-A levels lower in both male and female CKD patients than in their respective controls. Our results indicate that the bone formation and resorption parameters are altered in elderly male and female hemodialysis CKD patients. These changes may lead to vascular calcifications and cardiovascular complications, given that elevated OPG and OC levels and reduced fetuin-A levels are associated with cardiovascular events. 相似文献
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35.
Alvaro C. Ucero Alberto Benito-Martin Isabel Fuentes-Calvo Beatriz Santamaria Julia Blanco Jose M. Lopez-Novoa Marta Ruiz-Ortega Jesus Egido Linda C. Burkly Carlos Martinez-Salgado Alberto Ortiz 《生物化学与生物物理学报:疾病的分子基础》2013,1832(10):1744-1755
Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) regulates apoptosis, proliferation and inflammation in renal epithelial cells and plays a role in acute kidney injury. However, there is little information on the chronic effects of TWEAK. We hypothesized that TWEAK may influence renal fibrosis and regulate kidney fibroblast biology, in part, through Ras pathway.We studied a chronic model of experimental unilateral ureteral obstruction in wild type and TWEAK deficient mice, and a murine model of systemic TWEAK overexpression. TWEAK actions were also explored in cultured renal and embryonic fibroblasts.TWEAK and TWEAK receptor expression was increased in the obstructed kidneys. The absence of TWEAK decreased early kidney tubular damage, inflammatory infiltrates and myofibroblast number. TWEAK deficient mice had decreased renal fibrosis 21 days after obstruction, as assessed by extracellular matrix staining. In mice without prior underlying kidney disease, systemic overexpression of TWEAK induced kidney inflammation and fibrosis. In cultured fibroblasts, TWEAK induced proliferation through activation of the Ras/ERK pathway. TWEAK also activated nuclear factor κB (NFκB)-dependent inflammatory chemokine production in murine renal fibroblasts.In conclusion, lack of TWEAK reduces renal fibrosis in a model of persistent kidney insult and overexpression of TWEAK led to renal fibrosis. TWEAK actions on renal fibroblasts may contribute to the in vivo observations, as TWEAK promotes inflammatory activity and proliferation in fibroblast cultures. 相似文献
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Jordan L. Woehl Daisuke Takahashi Alvaro I. Herrera Brian V. Geisbrecht Om Prakash 《Biomolecular NMR assignments》2016,10(2):301-305
The pathogenic bacterium Staphylococcus aureus has evolved to actively evade many aspects of the human innate immune system by expressing a series of secreted inhibitory proteins. Among these, the extracellular adherence protein (Eap) has been shown to inhibit the classical and lectin pathways of the complement system. By binding to complement component C4b, Eap is able to inhibit formation of the CP/LP C3 pro-convertase. Secreted full-length, mature Eap consists of four ~98 residue domains, all of which adopt a similar beta-grasp fold, and are connected through a short linker region. Through multiple biochemical approaches, it has been determined that the third and fourth domains of Eap are responsible for C4b binding. Here we report the backbone and side-chain resonance assignments of the 11.3 kDa fourth domain of Eap. The assignment data has been deposited in the BMRB database under the accession number 26726. 相似文献
38.
Eva del Amo Cristina Esteva Susanna Hernandez-Bou Carmen Galles Marian Navarro Goretti Sauca Alvaro Diaz Paula Gassiot Carmina Marti Nieves Larrosa Pilar Ciruela Mireia Jane Raquel Sá-Le?o Carmen Mu?oz-Almagro Catalan Study Group of Invasive Pneumococcal Disease 《PloS one》2016,11(3)
The aim of this study was to study the serotypes and clonal diversity of pneumococci causing invasive pneumococcal disease in Catalonia, Spain, in the era of 13-valent pneumococcal conjugate vaccine (PCV13). In our region, this vaccine is only available in the private market and it is estimated a PCV13 vaccine coverage around 55% in children. A total of 1551 pneumococcal invasive isolates received between 2010 and 2013 in the Molecular Microbiology Department at Hospital Sant Joan de Déu, Barcelona, were included. Fifty-two serotypes and 249 clonal types—defined by MLST—were identified. The most common serotypes were serotype 1 (n = 182; 11.7%), 3 (n = 145; 9.3%), 19A (n = 137; 8.8%) and 7F (n = 122; 7.9%). Serotype 14 was the third most frequent serotype in children < 2 years (15 of 159 isolates). PCV7 serotypes maintained their proportion along the period of study, 16.6% in 2010 to 13.4% in 2013, whereas there was a significant proportional decrease in PCV13 serotypes, 65.3% in 2010 to 48.9% in 2013 (p<0.01). This decrease was mainly attributable to serotypes 19A and 7F. Serotype 12F achieved the third position in 2013 (n = 22, 6.4%). The most frequent clonal types found were ST306 (n = 154, 9.9%), ST191 (n = 111, 7.2%), ST989 (n = 85, 5.5%) and ST180 (n = 80, 5.2%). Despite their decrease, PCV13 serotypes continue to be a major cause of disease in Spain. These results emphasize the need for complete PCV13 vaccination. 相似文献
39.
Deforestation is associated with increased atmospheric CO2 and alterations to the surface energy and mass balances that can lead to local and global climate changes. Previous modelling studies show that the global surface air temperature (SAT) response to deforestation depends on latitude, with most simulations showing that high latitude deforestation results in cooling, low latitude deforestation causes warming and that the mid latitude response is mixed. These earlier conclusions are based on simulated large scal land cover change, with complete removal of trees from whole latitude bands. Using a global climate model we examine the effects of removing fractions of 5% to 100% of forested areas in the high, mid and low latitudes. All high latitude deforestation scenarios reduce mean global SAT, the opposite occurring for low latitude deforestation, although a decrease in SAT is simulated over low latitude deforested areas. Mid latitude SAT response is mixed. In all simulations deforested areas tend to become drier and have lower SAT, although soil temperatures increase over deforested mid and low latitude grid cells. For high latitude deforestation fractions of 45% and above, larger net primary productivity, in conjunction with colder and drier conditions after deforestation cause an increase in soil carbon large enough to produce a net decrease of atmospheric CO2. Our results reveal the complex interactions between soil carbon dynamics and other climate subsystems in the energy partition responses to land cover change. 相似文献
40.
Eva Venegas‐Moreno Alvaro Flores‐Martinez Elena Dios Mari C. Vazquez‐Borrego Alejandro Ibaez‐Costa Ainara Madrazo‐Atutxa Miguel A. Japn Justo P. Castao Raúl M. Luque David A. Cano Alfonso Soto‐Moreno 《Journal of cellular and molecular medicine》2019,23(5):3088-3096
Acromegaly is a rare disease resulting from hypersecretion of growth hormone (GH) and insulin‐like growth factor 1 (IGF1) typically caused by pituitary adenomas, which is associated with increased mortality and morbidity. Somatostatin analogues (SSAs) represent the primary medical therapy for acromegaly and are currently used as first‐line treatment or as second‐line therapy after unsuccessful pituitary surgery. However, a considerable proportion of patients do not adequately respond to SSAs treatment, and therefore, there is an urgent need to identify biomarkers predictors of response to SSAs. The aim of this study was to examine E‐cadherin expression by immunohistochemistry in fifty‐five GH‐producing pituitary tumours and determine the potential association with response to SSAs as well as other clinical and histopathological features. Acromegaly patients with tumours expressing low E‐cadherin levels exhibit a worse response to SSAs. E‐cadherin levels are associated with GH‐producing tumour histological subtypes. Our results indicate that the immunohistochemical detection of E‐cadherin might be useful in categorizing acromegaly patients based on the response to SSAs. 相似文献