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501.
de Andrade-Neto VF Pohlit AM Pinto AC Silva EC Nogueira KL Melo MR Henrique MC Amorim RC Silva LF Costa MR Nunomura RC Nunomura SM Alecrim WD Alecrim Md Chaves FC Vieira PP 《Memórias do Instituto Oswaldo Cruz》2007,102(3):359-365
In the present study, a quassinoid, neosergeolide, isolated from the roots and stems of Picrolemma sprucei (Simaroubaceae), the indole alkaloids ellipticine and aspidocarpine, isolated from the bark of Aspidosperma vargasii and A. desmanthum (Apocynaceae), respectively, and 4-nerolidylcatechol, isolated from the roots of Pothomorphe peltata (Piperaceae), all presented significant in vitro inhibition (more active than quinine and chloroquine) of the multi-drug resistant K1 strain of Plasmodium falciparum. Neosergeolide presented activity in the nanomolar range. This is the first report on the antimalarial activity of these known, natural compounds. This is also the first report on the isolation of aspidocarpine from A. desmanthum. These compounds are good candidates for pre-clinical tests as novel lead structures with the aim of finding new antimalarial prototypes and lend support to the traditional use of the plants from which these compounds are derived. 相似文献
502.
Andr Tavares da Silva Fernandes Silvia Bahadian Moreira Luciane Pinto Gaspar Marisol Simes Ana Carolina dos Reis Albuquerque Cajaraville Renata Carvalho Pereira Mariana Pierre de Barros Gomes Jos Henrique Rezende Linhares Vanessa de Oliveira Santos Renata Tourinho Santos Juliana Fernandes Amorim Tamiris Azamor da Costa Barros Juliana Gil Melgao Andra Marques Vieira da Silva Camilla Bayma Fernandes Luciana Neves Tubaro Jane da Silva Elena Cristina Caride Maria Beatriz Borges Rosane Cuber Guimares Renato Srgio Marchevsky Sheila Maria Barbosa de Lima Ana Paula Dinis Ano Bom Patrícia Cristina da Costa Neves Alcides Pissinatti Marcos da Silva Freire 《Journal of medical primatology》2021,50(1):36-45
503.
504.
Manuela da Silva Solcà Leila Andrade Bastos Carlos Eduardo Sampaio Guedes Marcelo Bordoni Lairton Souza Borja Daniela Farias Larangeira Pétala Gardênia da Silva Estrela Tuy Leila Denise Alves Ferreira Amorim Eliane Gomes Nascimento Geraldo Gileno de Sá Oliveira Washington Luis Conrado dos-Santos Deborah Bittencourt Mothé Fraga Patrícia Sampaio Tavares Veras 《PloS one》2014,9(7)
Host tissues affected by Leishmania infantum have differing degrees of parasitism. Previously, the use of different biological tissues to detect L. infantum DNA in dogs has provided variable results. The present study was conducted to evaluate the accuracy of molecular diagnostic testing (qPCR) in dogs from an endemic area for canine visceral leishmaniasis (CVL) by determining which tissue type provided the highest rate of parasite DNA detection. Fifty-one symptomatic dogs were tested for CVL using serological, parasitological and molecular methods. Latent class analysis (LCA) was performed for accuracy evaluation of these methods. qPCR detected parasite DNA in 100% of these animals from at least one of the following tissues: splenic and bone marrow aspirates, lymph node and skin fragments, blood and conjunctival swabs. Using latent variable as gold standard, the qPCR achieved a sensitivity of 95.8% (CI 90.4–100) in splenic aspirate; 79.2% (CI 68–90.3) in lymph nodes; 77.3% (CI 64.5–90.1) in skin; 75% (CI 63.1–86.9) in blood; 50% (CI 30–70) in bone marrow; 37.5% (CI 24.2–50.8) in left-eye; and 29.2% (CI 16.7–41.6) in right-eye conjunctival swabs. The accuracy of qPCR using splenic aspirates was further evaluated in a random larger sample (n = 800), collected from dogs during a prevalence study. The specificity achieved by qPCR was 76.7% (CI 73.7–79.6) for splenic aspirates obtained from the greater sample. The sensitivity accomplished by this technique was 95% (CI 93.5–96.5) that was higher than those obtained for the other diagnostic tests and was similar to that observed in the smaller sampling study. This confirms that the splenic aspirate is the most effective type of tissue for detecting L. infantum infection. Additionally, we demonstrated that LCA could be used to generate a suitable gold standard for comparative CVL testing. 相似文献
505.
Detection of an Allele Conferring Resistance to Bacillus sphaericus Binary Toxin in Culex quinquefasciatus Populations by Molecular Screening 下载免费PDF全文
Karlos Diogo de Melo Chalegre Tatiany Patrícia Romo Liliane Barbosa Amorim Daniela Bandeira Anastacio Rosineide Arruda de Barros Cludia Maria Fontes de Oliveira Lêda Regis Osvaldo Pompílio de-Melo-Neto Maria Helena Neves Lobo Silva-Filha 《Applied microbiology》2009,75(4):1044-1049
The activity of the Bacillus sphaericus binary (Bin) toxin on Culex quinquefasciatus larvae depends on its specific binding to the Cqm1 receptor, a midgut membrane-bound α-glucosidase. A 19-nucleotide deletion in the cqm1 gene (cqm1REC) mediates high-level resistance to Bin toxin. Here, resistance in nontreated and B. sphaericus-treated field populations of C. quinquefasciatus was assessed through bioassays as well as a specific PCR assay designed to detect the cqm1REC allele in individual larvae. Resistance ratios at 90% lethal concentration, gathered through bioassays, were close to 1 and indicate that the selected populations had similar levels of susceptibility to B. sphaericus, comparable to that of a laboratory colony. A diagnostic PCR assay detected the cqm1REC allele in all populations investigated, and its frequency in two nontreated areas was 0.006 and 0.003, while the frequency in the B. sphaericus-treated population was significantly higher. Values of 0.053 and 0.055 were detected for two distinct sets of samples, and homozygote resistant larvae were found. Evaluation of Cqm1 expression in individual larvae through α-glucosidase assays corroborated the allelic frequency revealed by PCR. The data from this study indicate that the cqm1REC allele was present at a detectable frequency in nontreated populations, while the higher frequency in samples from the treated area is, perhaps, correlated with the exposure to B. sphaericus. This is the first report of the molecular detection of a biolarvicide resistance allele in mosquito populations, and it confirms that the PCR-based approach is suitable to track such alleles in target populations. 相似文献
506.
dos Santos Rocha PB de Castro Amorim A de Sousa AF do Monte SJ da Mata Sousa LC do Nascimento Nogueira N Neto JM do Nascimento Marreiro D 《Biological trace element research》2011,143(2):603-611
Research has investigated the participation of zinc transport proteins and metallothionein in the metabolism of this mineral.
However, studies about the genetic expression of these proteins in obese patients are scarce. The study determined the expression
of zinc transporter protein codifying genes (ZnT-1, Zip-1 and Zip-3) and of metallothionein in 55 obese women, aged between
20 and 56 years. The assessment of body composition was carried out using anthropometric measurements and bioelectrical impedance.
Zinc intake was obtained by recording diet over a 3-day period, and the nutritional analysis was carried out using NutWin
software version 1.5. The plasmatic and erythrocytary zinc were analyzed by atomic absorption spectrophotometry (λ = 213. 9 nm). The determination of mRNA expression of the zinc transporter proteins and metallothionein was carried out using
blood, using the RT-PCR method. The mean values of body mass index were 37.9 ± 5.5 kg/m2. The average intake of zinc was 9.4 ± 2.3 mg/day. The analysis of the zinc plasma concentrations showed values of 58.4 ± 10.9 μg/dL.
The mean values of zinc in the erythroytes were 38.7 ± 9.1 μg/g Hb. The metallothionein gene had a higher expression in the
blood, when compared to zinc transporters ZnT-1, Zip-1, and Zip-3 (p = 0.01). The study shows that there are alterations in the biochemical parameters of zinc in obese patients assessed, as
well as higher expression of the codifying gene metallothionein, when compared to the investigated zinc transporters. 相似文献
507.
A genetic polymorphism of delta-aminolaevulinic acid dehydratase (ALAD) in the domestic rabbit, Oryctolagus cuniculus, was detected by starch gel electrophoresis. Family data (15 matings with 49 offspring) support the genetic model of two common codominant alleles at an autosomal locus. Gene frequencies were calculated in a random sample of 55 mixed breed, unrelated domestic rabbits: ALAD1 = 0.31 and ALAD2 = 0.69. 相似文献
508.
509.
Subunit A of coagulation factor XIII (F13A) and alpha-L-fucosidase (FUCA1) polymorphisms were studied in unrelated healthy blood donors from northern Portugal. The gene frequencies found were: F13A*2 = 0.241 and FUCA1*2 = 0.308. Segregation analysis in mother/child pairs and nuclear families confirmed the previously described modes of inheritance for F13A and FUCA1, and no evidence for silent genes was found. 相似文献
510.
V. C. Almada M. C. P. Amorim E. Pereira F. Almada R. Matos R. Godinho 《Journal of fish biology》1996,49(2):363-366
Agonistic behaviour and sound production were described for captive Gaidropsarus mediterraneus , a shore-dwelling gadoid. Thump-like sounds were produced during agonistic interactions, which involved disputes over access to shelter sites. 相似文献