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91.
The aphids Aphis gossypii and Myzus persicae are cosmopolitan, poliphagous and damage cultivated plants. The effects of the entomopathogenic fungi Beauveria bassiana (isolate IBCB 66), Metarhizium anisopliae (isolate IBCB 121), Paecilomyces fumosoroseus (isolate IBCB 141) and Lecanicillium (= Verticillium) lecanii (isolate JAB 02) on third instar nymphs of A. gossypii and M. persicae were evaluated in the laboratory at 25 degrees C, 70 +/- 10% RH and 12h photophase. The aphids were transferred to petri dishes with a foliar disk (cotton or pepper) with a layer of 1 cm tick of agar-water. The fungi were applied in a suspension containing 1.0 x 106 to 1.0 x 108 conidia/ml. In the control treatment 1 ml of sterilized water was added to the foliar disks. The mortality of aphids was evaluated daily. B. bassiana and M. anisopliae caused 100% mortality at the seventh day after inoculation, for both species. L. lecanii was the fungus that provided mortality later in the aphids and M. persicae was more susceptible to both fungi than A. gossypii. 相似文献
92.
Biomarkers for screening of lung cancer and pre-neoplastic lesions in a high risk Chilean population
Marta I Adonis Jose Díaz Veronica R Miranda Marco Chahuan Alcides Zambrano Hugo C Benitez Monica Campos Pablo Avaria Ulises Urzúa Pedro Marín Mariela Gohurdett Yasna Cisterna Lionel Gil 《Biological research》2014,47(1)
Background
The mortality of lung cancer (LC), increases each year in the world, in spite of any advances, in development of new drugs to advance stages of LC. The high incidence of LC has been associated with smoking habit, genetic diversity and environmental pollution. Antofagasta region has been reported to have the highest LC mortality rate in Chile and its inhabitants were exposed to arsenic in their drinking water in concentrations as high as 870 μg/L. Non-invasive techniques such as biomarkers (Automatic Quantitative Cytometry: AQC and DR70) and Auto Fluorescence Bronchoscopy (AFB) might be potentially useful as a supplementary diagnostic approach and early detection. Early detection is one of the most important factors to intervene and prevent cancer progression in LC. This is a work of an ongoing prospective bimodality cancer surveillance study in high risk LC volunteers. Enrolment was done in subjects from Antofagasta and Metropolitan regions. In addition, we enrolled subjects who were suspected of having lung cancer. AQC, DR70 and AFB were used as tools in the detection of pre-neoplastic (PNL) and neoplastic lesions (NL).Results
Half of the samples, classified as suspicious by AFB, were confirmed as metaplasia or dysplasia by histopathology. For LC, DR70 showed a higher sensitivity (95.8%) and specificity (91.9%) than AQC. However, for PNL AQC showed a higher sensitivity (91.9%) than DR70 (27.3%), although both with low PPV values. As a pre screener, both biomarkers might be employed as complementary tools to detect LC, especially as serially combined tests, with a sensitivity of 60% and a PPV of 65.2%. Additionally, the use of parallel combined tests might support the detection of PNL (sensitivity 91.2%; PPV 49.1%).Conclusion
This work adds information on cellular and molecular biomarkers to complement imaging techniques for early detection of LC in Latin America that might contribute to formulate policies concerning screening of LC. Supported by INNOVA-CORFO, Chile. 相似文献93.
94.
Lima Alexandre Bastos Fernandes Sobral Gisela Martins Gabriela Siqueira Pissinatti Alcides Viau Priscila de Oliveira Claudio Alvarenga 《International journal of primatology》2021,42(5):781-801
International Journal of Primatology - The Convention on Biological Diversity and the International Union for Conservation of Nature emphasize that ex situ conservation efforts are unavoidable.... 相似文献
95.
Camila V. Molina Marcos B. Heinemann Cecilia Kierulff Alcides Pissinatti Tiago F. da Silva Danilo G. de Freitas Gisele O. de Souza Bruno A. Miotto Adriana Cortez Beatriz de P. Semensato Luisa Z. Moreno Jos L. Cato‐Dias Marina G. Bueno 《American journal of primatology》2019,81(3)
The world currently faces severe biodiversity losses caused by anthropogenic activities such as deforestation, pollution, the introduction of exotic species, habitat fragmentation, and climate changes. Disease ecology in altered environments is still poorly understood. The golden‐headed lion tamarin (GHLT, Leontopithecus chrysomelas) is an endangered species that became invasive in an urban park in Niterói, Rio de Janeiro, Brazil. The initially few invasive GHLT individuals became hundreds, adapted to living in proximity to humans and domestic animals. These GHLTs were captured as part of a conservation project; some animals were translocated to Bahia and some were kept in captivity. This study tested 593 GHLT for Leptospira serology; 100 and 95 GHLT for polymerase chain reaction (PCR) toLeptospira and hepatitis E virus genotype 3 (HEV‐3), respectively, and 101 familiar groups for PCR to viruses (rotavirus A, norovirus GI and GII, and HEV‐3). One animal had antibodies for Leptospira serovar Shermani and another for serovar Hebdomadis. One saprophyticLeptospira was found by the 16S PCR and sequencing. Viruses were not detected in samples tested. Findings suggest that the epidemiological importance of such pathogens in this GHLT population is either low or nonexistent. These data are important to understand the local disease ecology, as well as monitoring a translocation project, and to contribute data for species conservation. 相似文献
96.
Paulo B. Chaves Tielli Magnus Leandro Jerusalinsky Maurício Talebi Karen B. Strier Paula Breves Fernanda Tabacow Rodrigo H. F. Teixeira Leandro Moreira Robson O. E. Hack Adriana Milagres Alcides Pissinatti Fabiano R. de Melo Cecília Pessutti Srgio L. Mendes Tereza C. Margarido Valria Fagundes Anthony Di Fiore Sandro L. Bonatto 《American journal of primatology》2019,81(12)
The taxonomy of muriquis, the largest extant primates in the New World, is controversial. While some specialists argue for a monotypic genus (Brachyteles arachnoides), others favor a two‐species classification, splitting northern muriquis (Brachyteles hypoxanthus) from southern muriquis (B. arachnoides). This uncertainty affects how we study the differences between these highly endangered and charismatic primates, as well as the design of more effective conservation programs. To address this issue, between 2003 and 2017 we collected over 230 muriqui fecal samples across the genus’ distribution in the Brazilian Atlantic Forest, extracted DNA from these samples, and sequenced 423 base pairs of the mitochondrial DNA (mtDNA) control region. Phylogenetic and species delimitation analyses of our sequence dataset robustly support two reciprocally monophyletic groups corresponding to northern and southern muriquis separated by an average 12.7% genetic distance. The phylogeographic break between these lineages seems to be associated with the Paraíba do Sul River and coincides with the transition between the north and south Atlantic Forest biogeographic zones. Published divergence estimates from whole mitochondrial genomes and nuclear loci date the split between northern and southern muriquis to the Early Pleistocene (ca. 2.0 mya), and our new mtDNA dataset places the coalescence time for each of these two clades near the last interglacial (ca. 120–80 kya). Our results, together with both phenotypic and ecological differences, support recognizing northern and southern muriquis as sister species that should be managed as distinct evolutionarily significant units. Given that only a few thousand muriquis remain in nature, it is imperative that conservation strategies are tailored to protect both species from extinction. 相似文献
97.
Francisco José García Jesús S. Troncoso José Carlos García-Gómez Juan Lucas Cervera 《Polar Biology》1993,13(6):417-421
During the expedition ANTARTIDA 8611 to the Scotia Sea, organized by the Spanish Oceanographic Institute, several specimens ofAustrodoris were collected. Although nearly all have been identified asAustrodoris kerguelenensis (Bergh, 1884), one of them shows some anatomical features, mainly related to the reproductive system, that allows us to identify this specimen as a new species, which we have namedA. georgiensis. Therefore, with the aim of clarifying the taxonomical value of this species, a comparative study of the anatomy ofA. kerguelenensis andA. georgiensis is presented. Some new data on the diet ofA. kerguelenensis are also presented. 相似文献
98.
1. In the presence of ATP, the Ca2+ pump of human red cell membranes catalyzes the hydrolysis of phosphate. The requirement for ATP of the Ca2+- activity was studied in relation to the two classes of site for ATP that are apparent during Ca2+ -ATPase activity. 2. (a) The for ATP as activator of the Ca2+ - extrapolated at 0 mM PNPP is equal to the of the Ca2+ -ATPase. (b) PNPP competes with ATP and its effectiveness is the same regardless the nucleotide acts as the substrate of the Ca2+ -ATPase or as activator of the Ca2+ -. 3. PNPP at the high-affinity site does not substitute for ATP as activator of the Ca2+ -. 4. At ATP concentrations that almost saturate the high-affinity site, Ca2+ - activity increases as a function of PNPP along an S-shaped curve, while Ca2+ -ATPase activity is partially inhibited along a curve of the same shape and apparent affinity. The fraction of Ca2+ -ATPase activity which is inhibited by PNPP is that which results from occupation of the low-affinity site by ATP. 5. Activation of the Ca2+ -ATPase by ATP at the low-affinity site is associated with inhibition of the Ca2+ - activity. Both phenomena take place with the same apparent affinity and along curves of the same shape. 6. Experimental results suggest that: (a) the Ca2+ - activity depends on ATP at the high-affinity site; (b) PNPP is hydrolyzed at the low-affinity site; (c) Ca2+ -ATPase activity at the high-affinity size persists during Ca2+ - activity. 相似文献
99.
de Mello MF Monteiro AB Fonseca EC Pissinatti A Ferreira AM 《American journal of primatology》2005,66(2):111-118
The aim of this study was to identify the presence of Helicobacter sp. in the gastric mucosa of captive marmosets (Callithrix sp.). Histologic specimens from the fundic, corpus, and antral gastric regions of six Callithrix jacchus, 12 C. kuhli, and 12 C. geoffroyi specimens were evaluated. The sections were stained with hematoxylin-eosin (H&E) and the Warthin-Starry silver impregnation method, and immunostained with rabbit anti-H. pylori polyclonal antibody. Helicobacter-like organisms (HLOs) and coccoid forms were present in silver-stained sections from 29 stomachs, whereas immunohistochemistry (IHC) tests revealed bacterial aggregates in 15 stomachs. No statistical difference relative to the presence of Helicobacter sp. was found among the gastric regions or marmoset species. Gastric lesions were found in the groups of marmosets that had positive and negative IHC results, but no correlation between inflammation and Helicobacter sp. infection was established. These findings demonstrate that marmosets are susceptible to naturally-occurring Helicobacter sp. infection, and open the way to the development of comparative studies on Helicobacter sp. infection in humans. 相似文献
100.
Coelho LM Silva MV Dini CY Giacon Neto AA Novo NF Silveira EP 《Memórias do Instituto Oswaldo Cruz》2004,99(6):553-557
A seroepidemiological survey for toxocariasis, among 180 schoolchildren of the public schools of Sorocaba City, state of S?o Paulo, Brazil, was carried out from August 2000 to July 2001. ELISA test was performed using excretory and secretory antigens for the detection of IgG anti-Toxocara antibodies. Information regarding the children was obtained from the parents or legal guardians. The results showed that the mean age was 5.4 +/- 1.4 years, the infection coefficient (IC) was 38.3 and the infection risk was higher among the children living in the city outskirts (IC = 47.4) where the socioeconomic conditions were worse than in the central region of the city (IC = 11.1). There was an association between higher frequency of seroreactivity in the ELISA test and the condition of living in a house with a yard and/or unpaved street. The same was observed in relation to a history of enteroparasitism. There was also an association between a seronegative ELISA test and previous treatment of pet dogs and/or cats with vermifuge. Based on these results, the authors propose that public health programs should include anthelmintic for dogs and cats during the antirabies vaccination campaigns, in order to diminish environmental contamination with Toxocara spp. eggs and consequently human infection. 相似文献