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121.
Pausas Juli G. Bladé Carme Valdecantos Alejandro Seva José P. Fuentes David Alloza José A. Vilagrosa Alberto Bautista Susana Cortina Jordi Vallejo Ramon 《Plant Ecology》2004,171(1-2):209-220
Pines have been extensively used for land restoration in the Mediterranean basin and in other parts of the world, since the late 19th century. The theoretical basis supporting pine utilisation was its stress-tolerant and pioneer features, and their attributed role of facilitating the development of late-successional hardwoods in the long-term. In the present work, the use of pines and hardwoods in forest restoration is discussed in the frame of the current disturbance regime and social demands for Mediterranean forests. Large pine plantations have recently disappeared because of their sensitivity to fire (e.g., Pinus nigra) or because of the short fire-intervals (e.g., Pinus halepensis). Combined pine and oak plantations are proposed for degraded land restoration on the basis of the complementary features of both groups of species. Seeding and containerised seedling plantation, soil amendments and plantation techniques to reduce transplant shock are evaluated for reforestation under water-stressing conditions, on the basis of several experiments performed in eastern Spain. Both P. halepensis and Quercus ilex are tested. 相似文献
122.
Jeimy D. Santiago‐Valentín Alma P. Rodríguez‐Troncoso Eric Bautista‐Guerrero Andrs Lpez‐Prez Amilcar L. Cupul‐Magaa 《Invertebrate Biology》2019,138(1):29-39
Porites panamensis is a hermatypic brooder coral endemic to, and distributed along, the Eastern Tropical Pacific, and is considered a species vulnerable to local effects because it has limited capacity for long‐distance dispersal (and low genetic diversity). Although larvae of P. panamensis have been previously shown to recruit to artificial settlement platforms, they have never been observed in the water column. The present study describes the reproductive behavior of P. panamensis, with a focus on using molecular tools to document evidence for a larval planktonic stage and for successful recruitment. Larvae collected from the water column, and recruitment on natural and artificial substrata were documented. Phylogenetic analysis of two ribosomal markers, 18s rRNA and ITS (ITS1‐5.8‐ITS2), and one mitochondrial marker, cytochrome oxidase subunit 1 (cox1), confirmed the taxonomic identity of larvae, and showed that larvae and recruits have genotypes similar to adults of P. panamensis. Lipid vacuoles and Symbiodinium sp. were present in the gastrodermis of all larvae. A total of 12 and 371 recruits settled on artificial and natural substrates, respectively, and the recruitment rate differed significantly over time. By documenting the reproductive success of the species, we show the potential for existing individuals both to maintain the population in the study area and to contribute to maintenance of the coral reef community in the coming decades. 相似文献
123.
Identification of de novo copy number variants associated with human disorders of sexual development 总被引:1,自引:0,他引:1
Tannour-Louet M Han S Corbett ST Louet JF Yatsenko S Meyers L Shaw CA Kang SH Cheung SW Lamb DJ 《PloS one》2010,5(10):e15392
Disorders of sexual development (DSD), ranging in severity from genital abnormalities to complete sex reversal, are among the most common human birth defects with incidence rates reaching almost 3%. Although causative alterations in key genes controlling gonad development have been identified, the majority of DSD cases remain unexplained. To improve the diagnosis, we screened 116 children born with idiopathic DSD using a clinically validated array-based comparative genomic hybridization platform. 8951 controls without urogenital defects were used to compare with our cohort of affected patients. Clinically relevant imbalances were found in 21.5% of the analyzed patients. Most anomalies (74.2%) evaded detection by the routinely ordered karyotype and were scattered across the genome in gene-enriched subtelomeric loci. Among these defects, confirmed de novo duplication and deletion events were noted on 1p36.33, 9p24.3 and 19q12-q13.11 for ambiguous genitalia, 10p14 and Xq28 for cryptorchidism and 12p13 and 16p11.2 for hypospadias. These variants were significantly associated with genitourinary defects (P = 6.08×10−12). The causality of defects observed in 5p15.3, 9p24.3, 22q12.1 and Xq28 was supported by the presence of overlapping chromosomal rearrangements in several unrelated patients. In addition to known gonad determining genes including SRY and DMRT1, novel candidate genes such as FGFR2, KANK1, ADCY2 and ZEB2 were encompassed. The identification of risk germline rearrangements for urogenital birth defects may impact diagnosis and genetic counseling and contribute to the elucidation of the molecular mechanisms underlying the pathogenesis of human sexual development. 相似文献
124.
Manuel Algara Meritxell Arenas Dolores De las Peñas Eloisa Bayo Julia Muñoz José Antonio Carceller Juan Salinas Ferran Moreno Francisco Martínez Ezequiel González Ángel Montero 《Reports of Practical Oncology and Radiotherapy》2012,17(3):122-128
AimTo evaluate the resources and techniques used in the irradiation of patients with breast cancer after lumpectomy or mastectomy and the status of implementation of new techniques and therapeutic schedules in our country.BackgroundThe demand for cancer care has increased among the Spanish population, as long as cancer treatment innovations have proliferated. Radiation therapy in breast cancer has evolved exponentially in recent years with the implementation of three-dimensional conformal radiotherapy, intensity modulated radiotherapy, image guided radiotherapy and hypofractionation.Material and MethodsAn original survey questionnaire was sent to institutions participating in the SEOR-Mama group (GEORM). In total, the standards of practice in 969 patients with breast cancer after surgery were evaluated.ResultsThe response rate was 70% (28/40 centers). In 98.5% of cases 3D conformal treatment was used. All the institutions employed CT-based planning treatment. Boost was performed in 56.4% of patients: electrons in 59.8%, photons in 23.7% and HDR brachytherapy in 8.8%. Fractionation was standard in 93.1% of patients. Supine position was the most frequent. Only 3 centers used prone position. The common organs of risk delimited were: homolateral lung (80.8%) and heart (80.8%). In 84% histograms were used. An 80.8% of the centers used isocentric technique. In 62.5% asymmetric fields were employed. CTV was delimited in 46.2%, PTV in 65% and both in 38.5%. A 65% of the centers checked with portal films. IMRT and hypofractionation were used in 1% and in 5.5% respectively.ConclusionIn most of centers, 3D conformal treatment and CT-based planning treatment were used. IMRT and hypofractionation are currently poorly implemented in Spain. 相似文献
125.
Ting Hway Wong Hai V. Nguyen Ming Terk Chiu Khuan Yew Chow Marcus Eng Hock Ong Gek Hsiang Lim Nivedita Vikas Nadkarni Dianne Carrol Tan Bautista Jolene Yu Xuan Cheng Lynette Mee Ann Loo Dennis Chuen Chai Seow 《PloS one》2015,10(9)
Background
Frailty is associated with adverse outcomes including disability, mortality and risk of falls. Trauma registries capture a broad range of injuries. However, frail patients who fall comprise a large proportion of the injuries occurring in ageing populations and are likely to have different outcomes compared to non-frail injured patients. The effect of frail fallers on mortality is under-explored but potentially significant. Currently, many trauma registries define low falls as less than three metres, a height that is likely to include non-frailty falls. We hypothesized that the low fall from less than 0.5 metres, including same-level falls, is a surrogate marker of frailty and predicts long-term mortality in older trauma patients.Methods
Using data from the Singapore National Trauma Registry, 2011–2013, matched till September 2014 to the death registry, we analysed adults aged over 45 admitted via the emergency department in public hospitals sustaining blunt injuries with an injury severity score (ISS) of 9 or more, excluding isolated hip fractures from same-level falls in the over 65. Patients injured by a low fall were compared to patients injured by high fall and other blunt mechanisms. Logistic regression was used to analyze 12-month mortality, controlling for mechanism of injury, ISS, revised trauma score (RTS), co-morbidities, gender, age and age-gender interaction. Different low fall height definitions, adjusting for injury regions, and analyzing the entire adult cohort were used in sensitivity analyses and did not change our findings.Results
Of the 8111 adults in our cohort, patients who suffered low falls were more likely to die of causes unrelated to their injuries (p<0.001), compared to other blunt trauma and higher fall heights. They were at higher risk of 12-month mortality (OR 1.75, 95% CI 1.18–2.58, p = 0.005), independent of ISS, RTS, age, gender, age-gender interaction and co-morbidities. Falls that were higher than 0.5m did not show this pattern. Males were at higher risk of mortality after low falls. The effect of age on mortality started at age 55 for males, and age 70 for females, and the difference was attributable to the additional mortality in male low-fallers.Conclusions
The low fall mechanism can optimize prediction of long-term mortality after moderate and severe injury, and may be a surrogate marker of frailty, complementing broader-based studies on aging. 相似文献126.
Linlin Su C. Yan Cheng Dolores D. Mruk 《The international journal of biochemistry & cell biology》2009,41(12):2578-2587
Throughout spermatogenesis, leptotene spermatocytes traverse the blood–testis barrier (BTB) to enter the adluminal compartment of the seminiferous epithelium for continued development. At the same time, the integrity of the BTB, which is constituted by co-existing tight junctions (TJ), basal ectoplasmic specializations (basal ES) and desmosome-like junctions, must be maintained since a breach in barrier function can result in spermatogenic arrest and even infertility. There is evidence to suggest that drug transporters may function at the BTB, but little is known about how they contribute to spermatogenesis. In this study, we investigate the role of P-glycoprotein (P-gp), a drug efflux pump, in BTB dynamics. A survey by RT-PCR revealed several transporter genes to be expressed by the testis, including Mdr1 (gene symbol for P-gp), Mrp1, Abcc5 and Slc15a1. It was also demonstrated that P-gp localizes to the BTB in all stages of the seminiferous epithelial cycle in the adult rat testis, as well as to the Sertoli cell–elongated spermatid interface in stages VII and VIII. We continued our study by examining the levels of several transporters in the testis following oral administration of Adjudin, a compound known to affect Sertoli–germ cell adhesion. In this experiment, the steady-state levels of P-gp, MRP1, ABCG1 and SLC15A1 were all found to increase by several-fold within hours of Adjudin treatment during junction restructuring. More importantly, an increase in P-gp association with TJ proteins (e.g., occludin, claudin-11 and JAM-A) was noted when testis lysates from Adjudin-treated rats were used for co-immunoprecipitation experiments, suggesting that P-gp may enhance BTB function during Sertoli–germ cell junction restructuring. 相似文献
127.
Gómez-Gallego F Garrido-Pertierra A Bautista JM 《The Journal of biological chemistry》2000,275(13):9256-9262
The enzyme variant glucose-6-phosphate dehydrogenase (G6PD) A(-), which gives rise to human glucose-6-phosphate dehydrogenase deficiency, is a protein of markedly reduced structural stability. This variant differs from the normal enzyme, G6PD B, in two amino acid substitutions. A further nondeficient variant, G6PD A, bears only one of these two mutations and is structurally stable. In this study, the synergistic structural defect in recombinant G6PD A(-) was reflected by reduced unfolding enthalpy due to loss of beta-sheet and alpha-helix interactions where both mutations are found. This was accompanied by changes in inner spatial distances between residues in the coenzyme domain and the partial disruption of tertiary structure with no significant loss of secondary structure. However, the secondary structure of G6PD A(-) was qualitatively affected by an increase in beta-sheets substituting beta-turns related to the lower unfolding enthalpy. The structural changes observed did not affect the active site of the mutant proteins, since its spatial position was unmodified. The final result is a loss of folding determinants leading to a protein with decreased intracellular stability. This is suggested as the cause of the enzyme deficiency in the red blood cell, which is unable to perform de novo protein synthesis. 相似文献
128.
Nonrandom insertion of Tn5 into cloned human adenovirus DNA 总被引:4,自引:0,他引:4
129.
Jose L. López-Campos Maria Abad Arranz Carmen Calero-Acu?a Fernando Romero-Valero Ruth Ayerbe-García Antonio Hidalgo-Molina Ricardo I. Aguilar-Pérez-Grovas Francisco García-Gil Francisco Casas-Maldonado Laura Caballero-Ballesteros María Sánchez-Palop Dolores Pérez-Tejero Alejandro Segado Jose Calvo-Bonachera Bárbara Hernández-Sierra Adolfo Doménech Macarena Arroyo-Varela Francisco González-Vargas Juan J. Cruz-Rueda 《PloS one》2016,11(3)
Objectives
Previous clinical audits of COPD have provided relevant information about medical intervention in exacerbation admissions. The present study aims to evaluate adherence to current guidelines in COPD through a clinical audit.Methods
This is a pilot clinical audit performed in hospital outpatient respiratory clinics in Andalusia, Spain (eight provinces with more than 8 million inhabitants), including 9 centers (20% of the public centers in the area) between 2013 and 2014. Cases with an established diagnosis of COPD based on risk factors, clinical symptoms, and a post-bronchodilator FEV1/FVC ratio of less than 0.70 were deemed eligible. The performance of the outpatient clinics was benchmarked against three guidance documents available at the time of the audit. The appropriateness of the performance was categorized as excellent (>80%), good (60−80%), adequate (40−59%), inadequate (20−39%), and highly inadequate (<20%).Results
During the audit, 621 clinical records were audited. Adherence to the different guidelines presented a considerable variability among the different participating hospitals, with an excellent or good adherence for symptom recording, MRC or CAT use, smoking status evaluation, spirometry, or bronchodilation therapy. The most outstanding areas for improvement were the use of the BODE index, the monitoring of treatments, the determination of alpha1-antitrypsin, the performance of exercise testing, and vaccination recommendations.Conclusions
The present study reflects the situation of clinical care for COPD patients in specialized secondary care outpatient clinics. Adherence to clinical guidelines shows considerable variability in outpatient clinics managing COPD patients, and some aspects of the clinical care can clearly be improved. 相似文献130.
Antibody Detection and Molecular Characterization of Toxoplasma gondii from Bobcats (Lynx rufus), Domestic Cats (Felis catus), and Wildlife from Minnesota,USA 下载免费PDF全文
Shiv K. Verma Larissa Minicucci Darby Murphy Michelle Carstensen Carolin Humpal Paul Wolf Rafael Calero‐Bernal Camila K. Cerqueira‐Cézar Oliver C.H. Kwok Chunlei Su Dolores Hill Jitender P. Dubey 《The Journal of eukaryotic microbiology》2016,63(5):567-571
Little is known of the epidemiology of toxoplasmosis in Minnesota. Here, we evaluated Toxoplasma gondii infection in 50 wild bobcats (Lynx rufus) and 75 other animals on/near 10 cattle farms. Antibodies to T. gondii were assayed in serum samples or tissue fluids by the modified agglutination test (MAT, cut‐off 1:25). Twenty nine of 50 bobcats and 15 of 41 wildlife trapped on the vicinity of 10 farms and nine of 16 adult domestic cats (Felis catus) and six of 14 domestic dogs resident on farms were seropositive. Toxoplasma gondii oocysts were not found in feces of any felid. Tissues of all seropositive wild animals trapped on the farm were bioassayed in mice and viable T. gondii was isolated from two badgers (Taxidea taxus), two raccoons (Procyon lotor), one coyote (Canis latrans), and one opossum (Didelphis virginiana). All six T. gondii isolates were further propagated in cell culture. Multi‐locus PCR‐RFLP genotyping using 10 markers (SAG1, SAG2 (5′‐3′SAG2, and alt.SAG2), SAG3, BTUB, GRA6, c22‐8, c29‐2, L358, PK1, and Apico), and DNA from cell culture derived tachyzoites revealed three genotypes; #5 ToxoDataBase (1 coyote, 1 raccoon), #1 (1 badger, 1 raccoon, 1 opossum), and #2 (1 badger). This is the first report of T. gondii prevalence in domestic cats and in bobcats from Minnesota, and the first isolation of viable T. gondii from badger. 相似文献