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521.
Jerônimo B. B. Sansevero Jorge M. Alonso Micael C. Booth Mateus M. Bueno Lucas S. Carvalho Nicoló Clemente Meri Diana S. Foesch Felipe A. Mateus Ricardo Valcarcel 《Restoration Ecology》2018,26(5):997-1004
Several ambitious restoration targets have been set for recovering degraded ecosystems in Brazil (21 million hectares with a legal deficit of native vegetation). The development of scientific knowledge and skilled professionals is necessary to meet this demand and is fundamental for achieving success in medium‐ and long‐term restoration. In this study, we describe the availability and profile of postgraduate courses on ecological restoration in Brazil. We surveyed 272 postgraduate programs, comprising six specific areas of concentration (forestry, soil sciences, botany, environmental engineering, ecology, and environmental science). We analyzed all selected courses in terms of location, approach (economic, social, and legal), and restoration techniques. Only 27% of the postgraduate programs analyzed offer ecological restoration courses, and 49% of these are offered in the southeast region of the country. Regions covered by nonforest ecosystems, such as Pampas, Caatinga, and Pantanal, were poorly represented. Legal aspects were considered in 51% of the courses, whereas social and economic approaches were only considered in 2.7 and 11% of the courses, respectively. Seedling planting (85%) and nucleation (68%) were the most frequently cited techniques of active restoration, and passive restoration was mentioned in 63% of the courses. Our findings highlight the need for increasing postgraduate courses in areas with nonforest ecosystems, especially due to a lack of knowledge about restoration of these areas. The incorporation of economic and social approaches is highly recommended, considering the importance of these attributes in achieving success in large‐scale restoration initiatives. 相似文献
522.
523.
Amoxicillin/tetracycline combinations are inadequate as alternative therapies for Helicobacter pylori infection 总被引:3,自引:0,他引:3
Background. Triple therapy with proton pump inhibitors or ranitidine bismuth citrate, clarithromycin and either amoxicillin or nitroimidazole derivatives are the present gold standards for cure of Helicobacter pylori infection. However, primary resistance to either clarithromycin or nitroimidazole derivatives is increasing and alternative therapies are needed. Aim. To determine the efficacy and safety of three regimens consisting of amoxicillin and tetracycline or doxycycline combined with either lansoprazole or ranitidine bismuth citrate. Methods. Two hundred and seventy H. pylori infected patients were randomly given one of the following treatments: amoxicillin 1 g twice a day (b.i.d.) plus tetracycline 500 mg four times a day (q.i.d.) with either lansoprazole 30 mg b.i.d. (group LAT) or ranitidine bismuth citrate 400 mg b.i.d. (group RBCAT) for 7 days and amoxicillin 1 g b.i.d. plus doxycycline 100 mg b.i.d. and lansoprazole 30 mg b.i.d. for 14 days (group LAD). Eradication rate was assessed by UBT at 4–6 weeks after therapy. Results. The three groups (LAT, RBCAT, and LAD) of patients achieved eradication rates of 35% (25–45), 20% (12–29) and 36% (25–46), respectively, on intention‐to‐treat analysis. Patient compliance was optimal and side‐effects minimal in all three groups. Conclusions. Although the amoxicillin/tetracycline combination is attractive (inexpensive, safe, and with low primary resistance rate), it can not be recommended for H. pylori eradication. 相似文献
524.
Alfonso González Ramírez Juan José Calvo Aguirre Pilar Lekuona Ancizar Juan Luis González Oliveras Teresa Marcellán Benavente Ana Ruiz de Gordoa Armendia Antoni Salvá Casanovas Pablo Alcalde Tirado Teresa González Alonso Reyes Padilla Clemente Mercedes Clerencia Sierra Elena Ubis Diez 《Revista espa?ola de geriatría y gerontología》2013
The Workshop on Osteoporosis, Falls and Fractures (GCOF) of The Spanish Geriatrics and Gerontology Society (SEGG) formed a committee in order to review the state of the art on the detection, risk factors and assessment tools for falls, and intervention protocols when falls occurs in nursing homes, long-term hospitals or medium-stay units. The different patient profiles are described in order to make a comprehensive approach to this heterogeneous topic and population, offering a risk classification and specific advice according to these categories. 相似文献
525.
Simone Giovannuzzi Chad S. Hewitt Alessio Nocentini Clemente Capasso Daniel P. Flaherty Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):333
Coumarins are known to act as prodrug inhibitors of mammalian α-carbonic anhydrases (CAs, EC 4.2.1.1) but they were not yet investigated for the inhibition of bacterial α-CAs. Here we demonstrate that such enzymes from the bacterial pathogens Neisseria gonorrhoeae (NgCAα) and Vibrio cholerae (VchCAα) are inhibited by a panel of simple coumarins incorporating hydroxyl, amino, ketone or carboxylic acid ester moieties in various positions of the ring system. The nature and the position of the substituents in the coumarin ring were the factors which strongly influenced inhibitory efficacy. NgCAα was inhibited with KIs in the range of 28.6–469.5 µM, whereas VchCAα with KIs in the range of 39.8–438.7 µM. The two human (h)CA isoforms included for comparison reason in the study, hCA I and II, were less prone to inhibition by these compounds, with KIs of 137–948.9 µM for hCA I and of 296.5–961.2 µM for hCA II, respectively. These findings are relevant for discovering coumarin bacterial CA inhibitors with selectivity for the bacterial over human isoform, with potential applications as novel antibacterial agents. 相似文献
526.
Alessio Nocentini Andrea Angeli Fabrizio Carta Jean-Yves Winum Raivis Zalubovskis Simone Carradori Clemente Capasso William A. Donald Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):561
Inorganic anions inhibit the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) generally by coordinating to the active site metal ion. Cyanate was reported as a non-coordinating CA inhibitor but those erroneous results were subsequently corrected by another group. We review the anion CA inhibitors (CAIs) in the more general context of drug design studies and the discovery of a large number of inhibitor classes and inhibition mechanisms, including zinc binders (sulphonamides and isosteres, dithiocabamates and isosteres, thiols, selenols, benzoxaboroles, ninhydrins, etc.); inhibitors anchoring to the zinc-coordinated water molecule (phenols, polyamines, sulfocoumarins, thioxocoumarins, catechols); CAIs occluding the entrance to the active site (coumarins and derivatives, lacosamide), as well as compounds that bind outside the active site. All these new chemotypes integrated with a general procedure for obtaining isoform-selective compounds (the tail approach) has resulted, through the guidance of rigorous X-ray crystallography experiments, in the development of highly selective CAIs for all human CA isoforms with many pharmacological applications. 相似文献
527.
528.
A rapid and reproducible Agrobacterium-mediated transformation protocol for sorghum has been developed. The protocol uses the nptII selectable marker gene with either of the aminoglycosides geneticin or paromomycin. A screen of various A. tumefaciens strains revealed that a novel C58 nopaline chromosomal background carrying the chrysanthopine disarmed Ti plasmid pTiKPSF2, designated NTL4/Chry5, was most efficient for gene transfer to sorghum immature embryos. A NTL4/Chry5 transconjugant harboring the pPTN290 binary plasmid, which carries nptII and GUSPlus
TM
expression cassettes, was used in a series of stable transformation experiments with Tx430 and C2-97 sorghum genotypes and approximately 80% of these transformation experiments resulted in the recovery of at least one transgenic event. The transformation frequencies among the successful experiments ranged from 0.3 to 4.5%, with the average transformation frequency being approximately 1% for both genotypes. Over 97% of the transgenic events were successfully established in the greenhouse and were fully fertile. Co-expression of GUSPlus
TM
occurred in 89% of the transgenic T0 events. Seed set for the primary transgenic plants ranged from 145 to 1400 seed/plant. Analysis of T1 progeny demonstrated transmission of the transgenes in a simple Mendelian fashion in the majority of events. 相似文献
529.
Peter JI Ellis Lydia Ferguson Emily J Clemente Nabeel A Affara 《BMC evolutionary biology》2007,7(1):171
Background
The male-specific region of the mouse Y chromosome long arm (MSYq) contains three known highly multi-copy X-Y homologous gene families, Ssty1/2, Sly and Asty. Deletions on MSYq lead to teratozoospermia and subfertility or infertility, with a sex ratio skew in the offspring of subfertile MSYqdel males 相似文献530.
Jagdeep Kaur John Fellers Alok Adholeya Siva L. S. Velivelli Kaoutar El-Mounadi Natalya Nersesian Thomas Clemente Dilip Shah 《Transgenic research》2017,26(1):37-49
Rust fungi of the order Pucciniales are destructive pathogens of wheat worldwide. Leaf rust caused by the obligate, biotrophic basidiomycete fungus Puccinia triticina (Pt) is an economically important disease capable of causing up to 50 % yield losses. Historically, resistant wheat cultivars have been used to control leaf rust, but genetic resistance is ephemeral and breaks down with the emergence of new virulent Pt races. There is a need to develop alternative measures for control of leaf rust in wheat. Development of transgenic wheat expressing an antifungal defensin offers a promising approach to complement the endogenous resistance genes within the wheat germplasm for durable resistance to Pt. To that end, two different wheat genotypes, Bobwhite and Xin Chun 9 were transformed with a chimeric gene encoding an apoplast-targeted antifungal plant defensin MtDEF4.2 from Medicago truncatula. Transgenic lines from four independent events were further characterized. Homozygous transgenic wheat lines expressing MtDEF4.2 displayed resistance to Pt race MCPSS relative to the non-transgenic controls in growth chamber bioassays. Histopathological analysis suggested the presence of both pre- and posthaustorial resistance to leaf rust in these transgenic lines. MtDEF4.2 did not, however, affect the root colonization of a beneficial arbuscular mycorrhizal fungus Rhizophagus irregularis. This study demonstrates that the expression of apoplast-targeted plant defensin MtDEF4.2 can provide substantial resistance to an economically important leaf rust disease in transgenic wheat without negatively impacting its symbiotic relationship with the beneficial mycorrhizal fungus. 相似文献