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71.
Marine invertebrate populations usually show high levels of genetic variability that has frequently been associated with spatial
and temporal environmental heterogeneity. One of the most heterogeneous marine environments is the intertidal zone, the habitat
of Collisella subrugosa, the most widespread and abundant Brazilian limpet. C. subrugosa has planktonic larvae that can disperse over long distances, what can promote gene flow among shores, working against interpopulational
differentiation. In this study we investigated the genetic variability and populational substructure of C. subrugosa through analysis of 24 allozyme loci in 14 samples (590 individuals) collected along 2,700 km of the Brazilian coast. The
genetic variability was high ( and ), as expected for intertidal species. Genetic differentiation among samples was low (F
ST = 0.03) what may reflect intensive gene flow associated with larval dispersal. However, we detected an isolation-by-distance
pattern of population substructure in one sampled region. High levels of heterozygote deficiency were also observed for many
loci in each sample. Alternative hypothesis are discussed, and the “breeding groups” is suggested to explain these pattern,
indicating the main cause as environmental heterogeneity. 相似文献
72.
Spanamberg A Wünder EA Brayer Pereira DI Argenta J Cavallini Sanches EM Valente P Ferreiro L 《Revista iberoamericana de micología》2008,25(3):154-156
Mastitis is one of the most serious problems in the dairy cattle farms. The great majority of the cases are caused by bacteria, but lately there have been an increasing number of reports about cases of mycotic etiology. The objective of this work was to characterize the yeasts and yeast-like fungi associated with milk of cows with mastitis. Milk samples (n = 248) from a dairy belt situated around the region of Passo Fundo, hinterland of the state of Rio Grande do Sul, Southern Brazil, were analyzed. Aliquots of 0.1 ml of milk were inoculated on yeast extract-malta agar with chloramphenicol. After a period of incubation of 3-5 days at 22-25 degrees C, the counting of the morphologically distinct colonies was performed, as well as the isolation and identification through phenotypical and physiological criteria. It was possible to isolate 68 yeast species from 43 (17.3%) of the samples. The most frequent genera were Candida (37.9%), Pichia (19.1%), Cryptococcus (10.3%) and Rhodotorula (10.3%). 相似文献
73.
Jaqueline Raymondi Silva Larissa Campos de Medeiros Vinícius Pinho dos Reis Juliana Helena Chávez Thiago Demarchi Munhoz Gustavo Puia Borges Otavio Augusto Brioschi Soares Carlos Henrique Coelho de Campos Rosangela Zacarias Machado Cristiane Divan Baldani Maria Luana Cristiny Rodrigues Silva Joice Lara Maia Faria Edson Elias da Silva Luiz Tadeu Moraes Figueiredo 《Memórias do Instituto Oswaldo Cruz》2013,108(7):921-923
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country. 相似文献
74.
Pitta MG Silva AC Neves JK Silva PG Irmão JI Malagueño E Santana JV Lima MC Galdino SL Pitta IR Albuquerque MC 《Memórias do Instituto Oswaldo Cruz》2006,101(Z1):313-316
The emergence of strains of Schistosoma resistant to praziquantel has drawn attention to the search for new schistosomacide drugs. Imidazolidinic derivatives have performed outstandingly against adult S. mansoni worms when evaluated in vitro. The molecular modification of imidazolidine by way of bioisosteric replacement gives rise to variations in its biological response. This study verifies the potential of substituent groups in the derivatives (Z)3-benzyl-5-(2-fluoro-benzylidene)-imidazolidine-2,4-dione NE4, 3-benzyl-5-(4-chloro-arylazo)-4-thioxo-imidazolidin -2-ona PT5, 3-benzyl-5-(3-fluoro-benzylidene)-1-methyl-2-thioxo-imidazolidin-4-one JT53; 3-benzyl-1-methyl-5-(4-methyl-benzylidene)-2-thioxo-imidazolidin-4-one JT63; 3-benzyl-1-methyl-5-(4-methoxi-benzylidene)-2-thioxo -imidazolidin-4-one JT68; 3-(4-chloro-benzyl)-1-methyl-5-(4-methoxi-benzylidene)-2-thioxo-imidazolidin-4-one JT69; 3-(4-phenyl-benzyl)-1-methyl-5-(4-methoxi-benzylidene)-2-thioxo-imidazolidin-4-one JT72 by determining the viability in vitro of adult S. mansoni worms in the presence of these derivatives. The susceptibility of the worms obtained from mice and kept in culture in the presence of different concentrations was determined by way of schistosomacide kinetic, observed every 24 h over a period of eight days. The results show that the worms were more sensitive to the PT5 derivative at a concentration of 58 microM which killed 100% of the worms after 24 h of contact, also giving rise to alterations in the tegument surface of the worms with the formation of bubbles and peeling. These observations suggest a strong electronic contribution of the arylazo grouping in the biological response. 相似文献
75.
Yohe HC O'Hara KA Hunt JA Kitzmiller TJ Wood SG Bement JL Bement WJ Szakacs JG Wrighton SA Jacobs JM Kostrubsky V Sinclair PR Sinclair JF 《American journal of physiology. Gastrointestinal and liver physiology》2006,290(6):G1269-G1279
The objective of this study was to determine whether Toll-like receptor 4 (TLR4) has a role in alcohol-mediated acetaminophen (APAP) hepatotoxicity. TLR4 is involved in the inflammatory response to endotoxin. Others have found that ethanol-mediated liver disease is decreased in C3H/HeJ mice, which have a mutated TLR4 resulting in a decreased response to endotoxin compared with endotoxin-responsive mice. In the present study, short-term (1 wk) pretreatment with ethanol plus isopentanol, the predominant alcohols in alcoholic beverages, caused no histologically observed liver damage in either C3H/HeJ mice or endotoxin-responsive C3H/HeN mice, despite an increase in nitrotyrosine levels in the livers of C3H/HeN mice. In C3H/HeN mice pretreated with the alcohols, subsequent exposure to APAP caused a transient decrease in liver nitrotyrosine formation, possibly due to competitive interaction of peroxynitrite with APAP producing 3-nitroacetaminophen. Treatment with APAP alone resulted in steatosis in addition to congestion and necrosis in both C3H/HeN and C3H/HeJ mice, but the effects were more severe in endotoxin-responsive C3H/HeN mice. In alcohol-pretreated endotoxin-responsive C3H/HeN mice, subsequent exposure to APAP resulted in further increases in liver damage, including severe steatosis, associated with elevated plasma levels of TNF-alpha. In contrast, alcohol pretreatment of C3H/HeJ mice caused little to no increase in APAP hepatotoxicity and no increase in plasma TNF-alpha. Portal blood endotoxin levels were very low and were not detectably elevated by any of the treatments. In conclusion, this study implicates a role of TLR4 in APAP-mediated hepatotoxicity. 相似文献
76.
Falcão Fábio Dodonov Pavel Caselli Christini B. dos Santos Juliana Silveira Faria Deborah 《Biodiversity and Conservation》2021,30(8-9):2545-2564
Biodiversity and Conservation - Tropical forests are being lost and modified at an unprecedented rate, with extant biodiversity increasingly restricted to human-modified landscapes. Resulting... 相似文献
77.
Lêda N. Regis Ridelane Veiga Acioli José Constantino Silveira Jr. Maria Alice Varjal Melo-Santos Wayner Vieira Souza Candida M. Nogueira. Ribeiro Juliana C. Serafim. da Silva Antonio Miguel Vieira Monteiro Cláudia M. F. Oliveira Rosangela M. R. Barbosa Cynthia Braga Marco Aurélio Benedetti Rodrigues Marilú Gomes N. M. Silva Paulo Justiniano Ribeiro Jr. Wagner Hugo Bonat Liliam César de Castro Medeiros Marilia Sa Carvalho André Freire Furtado 《PloS one》2013,8(7)
Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program. 相似文献
78.
79.
da Paz Priscila Marques de Oliveira Juliana 《Bioprocess and biosystems engineering》2018,41(5):697-706
Bioprocess and Biosystems Engineering - This work is based on the importance of monitoring the thermodynamic variables of sugarcane juice fermentation by Saccharomyces cerevisiae, using a numerical... 相似文献
80.
Elena Marinova Sandy P. Harrison Fran Bragg Simon Connor Veronique de Laet Suzanne A.G. Leroy Petra Mudie Juliana Atanassova Elissaveta Bozilova Hülya Caner Carlos Cordova Morteza Djamali Mariana Filipova‐Marinova Natalia Gerasimenko Susanne Jahns Katerina Kouli Ulrich Kotthoff Eliso Kvavadze Maria Lazarova Elena Novenko Elias Ramezani Astrid Röpke Lyudmila Shumilovskikh Ioan Tanţǎu Spassimir Tonkov 《Journal of Biogeography》2018,45(2):484-499