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1.
J Cancer Res Clin Oncol ; 145(12): 2891-2899, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31617076

RESUMO

PURPOSE: Microsatellites are widely distributed repetitive DNA motifs, accounting for approximately 3% of the genome. Due to mismatch repair system deficiency, insertion or deletion of repetitive units often occurs, leading to microsatellite instability. In this review, we aimed to explore the relationship between MSI and biological behaviour of colorectal carcinoma, gastric carcinoma, lymphoma/leukaemia and endometrial carcinoma, as well as the application of frameshift peptide vaccines in cancer therapy. METHODS: The relevant literature from PubMed and Baidu Xueshu were reviewed in this article. The ClinicalTrials.gov database was searched for clinical trials related to the specific topic. RESULTS: Microsatellite instability is divided into three subtypes: high-level, low-level microsatellite instability, and stable microsatellites. The majority of tumour patients with high-level microsatellite instability often show a better efficacy and prognosis than those with low-level microsatellite instability or stable microsatellites. In coding regions, especially for genes involved in tumourigenesis, microsatellite instability often results in inactivation of proteins and contributes to tumourigenesis. Moreover, the occurrence of microsatellite instability in coding regions can also cause the generation of frameshift peptides that are thought to be unknown and novel to the individual immune system. Thus, these frameshift peptides have the potential to be biomarkers to raise tumour-specific immune responses. CONCLUSION: MSI has the potential to become a key predictor for evaluating the degree of malignancy, efficacy and prognosis of tumours. Clinically, MSI patterns will provide more valuable information for clinicians to create optimal individualized treatment strategies based on frameshift peptides vaccines.


Assuntos
Mutação da Fase de Leitura/genética , Repetições de Microssatélites/genética , Neoplasias/genética , Animais , Carcinogênese/genética , Ensaios Clínicos como Assunto , Reparo de Erro de Pareamento de DNA/genética , Humanos , Instabilidade de Microssatélites , Prognóstico
2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(8): 992-996, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31484267

RESUMO

Objective: To analyze the genetic diversity of Aedes albopictus populations in the coastal areas of southern China by using the microsatellite markers to provide a basis for the control of vectors. Methods: Genetic diversity and clustering analysis of Aedes albopictus populations were studied in the 7 microsatellite loci, in Hangzhou, Ningbo and Yiwu of Zhejiang province, Longyan of Fujian province, Guangzhou of Guangdong province, Nanning of Guangxi Zhuang Autonomous Region and Haikou of Hainan province. Results: Numbers of different alleles (5.429-7.571), effective alleles (2.897-3.632), allele richness (5.236-7.170) and expected heterozygosity (0.538- 0.637) were detected from each of the Aedes albopictus population by using 7 microsatellite markers. The inbreeding coefficients appeared as 0.008-0.332, with heterozygote deficiency, in these populations. Fixation index of the whole populations was 0.058, suggesting that the genetic variation among the 7 populations was 5.8%. Data from the Neighbor-Joining clustering analysis showed that populations from Hangzhou and Yiwu belonged to one branch while Longyan and Guangzhou populations constituted another branch. Aedes albopictus populations of Nanning and Haikou showed great genetic variation but formed a single branch. Bayesian analysis on Aedes albopictus populations showed that the possible number of clusters was 3. Conclusions: Based on 7 microsatellite loci, relatively high genetic diversity and medium level of genetic differentiation that increasing with the geographical distances, were found in these Aedes albopictus populations, from the coastal areas in southern China.


Assuntos
Aedes/genética , Variação Genética , Repetições de Microssatélites , Aedes/classificação , Animais , Teorema de Bayes , China , Repetições de Microssatélites/genética , Mosquitos Vetores , Filogenia
3.
Plant Dis ; 103(11): 2751-2758, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31509494

RESUMO

Didymella pisi is the primary causal pathogen of Ascochyta blight (AB) of dry pea in Montana. Diagnosis of AB is challenging because there are six different species that cause AB worldwide and that can co-occur. Additionally, agar plate identification of D. pisi is challenging due to its slow growth rate. Currently, there are no PCR-based assays developed for specific detection of D. pisi or any fungal pathogen in the AB complex of dry pea. In this study, we evaluated simple sequence repeat (SSR) primer pairs for their specificity and sensitivity in real-time and conventional SSR-PCR both in vitro and in planta. The specificity of the assay was determined by testing DNA of 10 dry pea varieties, fungal species in the AB complex, and fungal species associated with dry pea. To avoid false-negative results, plant and fungal DNA markers were included as controls in a conventional multiplex SSR-PCR, to amplify any plant or fungal DNA in the absence of the D. pisi SSR target. SYBR Green SSR-quantitative PCR (qPCR) detection was conducted using the same primer pairs but in a uniplex format. D. pisi was specifically amplified, whereas other fungi and host DNA were not. Also, sensitivity experiments showed that the detection limit was 0.01 ng of DNA of D. pisi for both assays and 100 conidia in SSR-qPCR. These assays are valuable diagnostic tools for the detection of D. pisi.


Assuntos
Ascomicetos , Técnicas Microbiológicas , Ervilhas , Reação em Cadeia da Polimerase , Ascomicetos/genética , Limite de Detecção , Técnicas Microbiológicas/métodos , Repetições de Microssatélites/genética , Montana , Ervilhas/microbiologia
4.
An Acad Bras Cienc ; 91(3): e20180749, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531533

RESUMO

Due to the increasing search for renewable resources, plant fibers have become an alternative when creating new products. Studies demonstrate the potential use of pineapple fibers in composites. The objective of this work was to evaluate the genetic diversity and verify any association between ISSR (Inter Simple Sequence Repeats) bands and quality of pineapple fibers for use in cements in the civil construction. The study analyzed the genetic variability of 11 pineapple genotypes, as well as the possible association of 131 bands from 16 ISSR markers with fiber quality characteristics. Eleven bands were selected based on their high correlations (0.64578* to 0.72457*) with three fiber quality variables. Of these, two bands were purified, sequenced, and blasted against sequences in GenBank at NCBI. These markers can be used in marker assisted selection to genetically improve the quality of pineapple fiber. Bands that returned no hits in the NCBI BLAST search can be deposited as new sequences in the GenBank. Therefore, the SCAR markers, once validated, can be useful in pineapple genetic breeding programs worldwide by using molecular marker assisted selection for fiber resistance, which could subsidize the development of more promising genotypes for industrial use and contribute to the sustainability of this new production sector.


Assuntos
Ananas/genética , Marcadores Genéticos , Repetições de Microssatélites/genética , Cruzamento , Variação Genética , Genótipo , Filogenia , Polimorfismo Genético , Estatísticas não Paramétricas
5.
Cytogenet Genome Res ; 158(3): 160-169, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31394537

RESUMO

The discovery of sex chromosome systems in non-model organisms has elicited growing recognition that sex chromosomes evolved via diverse paths that are not fully elucidated. Lineages with labile sex determination, such as turtles, hold critical cues, yet data are skewed toward hide-neck turtles (suborder Cryptodira) and scant for side-neck turtles (suborder Pleurodira). Here, we used classic and molecular cytogenetics to investigate Emydura subglobosa (ESU), an unstudied side-neck turtle with genotypic sex determination from the family Chelidae, where extensive morphological divergence exists among XX/XY systems. Our data represent the first cytogenetic description for ESU. Similarities were found between ESU and E. macquarii (EMA), such as identical chromosome number (2n = 50), a single and dimorphic nucleolus organizer region (NOR) localized in a microchromosome pair (ESU14) of both sexes (detected via FISH of 18S rDNA). Only the larger NOR is active (detected by silver staining). As in EMA, comparative genome hybridization revealed putative macro XX/XY chromosomes in ESU (the 4th largest pair). Our comparative analyses and revaluation of previous data strongly support the hypothesis that Emydura's XX/XY system evolved via fusion of an ancestral micro-Y (retained by Chelodina longicollis) onto a macro-autosome. This evolutionary trajectory differs from the purported independent evolution of XX/XY from separate ancestral autosomes in Chelodina and Emydura that was previously reported. Our data permit dating this Y-autosome fusion to at least the split of Emydura around 45 Mya and add critical information about the evolution of the remarkable diversity of sex-determining mechanisms in turtles, reptiles, and vertebrates.


Assuntos
Evolução Molecular , Cromossomos Sexuais/genética , Tartarugas/genética , Animais , Hibridização Genômica Comparativa , Hibridização in Situ Fluorescente , Cariótipo , Masculino , Repetições de Microssatélites/genética , RNA Ribossômico 18S/genética , Coloração pela Prata , Tartarugas/classificação
6.
Anticancer Res ; 39(8): 4315-4324, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366523

RESUMO

BACKGROUND/AIM: This study aimed to obtain accurate differential diagnosis (DDx) of multicentric carcinogenesis (MC) and intrahepatic metastasis (IM) in recurrent lesions of hepatocellular carcinoma. MATERIALS AND METHODS: A total of 79 patients who underwent re-hepatectomy (2000-2013) were examined. PCR was used to analyze 13 chromosomal microsatellite loci by PCR. On the basis of this genetic analysis, the recurrent lesions were diagnosed as IM, MC or not determined (ND). Subsequently, DDx was compared with types of resection and outcome. RESULTS: The recurrent lesions were diagnosed as IM in 33 patients, MC in 44, and ND in 2. The anatomical resection group included 14 IM lesions (28%) and 36 MC lesions (72%), while the non-anatomical resection group included 19 IM lesions (70%) and 8 MC lesions (30%) (p<0.001). CONCLUSION: Anatomical resection at initial hepatectomy may reduce the likelihood of IM recurrence, leading to a better outcome for patients with HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Metástase Neoplásica/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Adulto , Idoso , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Diagnóstico Diferencial , Feminino , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia
7.
Parasitol Res ; 118(9): 2475-2484, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31270681

RESUMO

The Asian bush mosquito Aedes japonicus, endemic to East Asia, is one of the most expansive mosquito species in the world and has as yet established in 15 countries of Europe. Within Germany, the species has been spreading tremendously during the last years, and its four once geographically isolated populations were on the verge of merging in 2017. To reveal relationships and carry-over ways between the various populations, and thus, migration and displacement routes, the genetic make-up of Ae. japonicus from ten different locations throughout its German distribution area was investigated. For this purpose, a part of the mitochondrial DNA (nad4 gene) of collected specimens was sequenced and seven loci of short tandem repeats (microsatellites) were genotyped. When related to similar genetic studies carried out between 2012 and 2015, the results suggest that admixtures had since occurred, but no complete genetic mixture of populations had taken place. At the time of sampling for the present study, the western collection sites were still uniform in their genetic make-up; however, a carry-over of individuals from the southeastern to the northern and southwestern German populations was determined. Further introductions from abroad are possible. In summary, the genetic diversity of Ae. japonicus in Germany had grown considerably, thus increasing ecological variability and adaptability of the species. At this point (10 years after the first detection), it is not possible anymore to draw conclusions on the origins of the populations.


Assuntos
Aedes/genética , DNA Mitocondrial/genética , Variação Genética/genética , Espécies Introduzidas/estatística & dados numéricos , Repetições de Microssatélites/genética , Animais , Genética Populacional , Genótipo , Alemanha
8.
Aquat Toxicol ; 214: 105235, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31271906

RESUMO

Corbicula fluminea is highly sensitive to ammonia, and its response mechanism to ammonia stress is unclear. In this study, C. fluminea was exposed to different levels of ammonia (control group, 10 mg/L, and 25 mg/L) for 24 h and 48 h. A comparative analysis of transcriptome sequencing (RNA-seq) of C. fluminea digestive gland showed that the expression of 6742 genes (11.54%) was significantly affected by ammonia stress. The TLR, NF-κB, FOXO, and apoptotic signaling pathways were involved in the regulation. The differential expression of 14 genes was confirmed by real-time PCR. In summary, the response mechanism of C. fluminea digestive gland under ammonia stress may be different from that of oxidative stress in marine vertebrates. Also, the NMDAR-mediated pathway may not be the main mechanism in the response to ammonia stress in C. fluminea. The present study is a preliminary study for further investigation into ammonia toxicity in shellfish.


Assuntos
Amônia/toxicidade , Corbicula/genética , Corbicula/fisiologia , Perfilação da Expressão Gênica , Estresse Fisiológico/genética , Animais , Corbicula/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Repetições de Microssatélites/genética , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único/genética , Mapas de Interação de Proteínas/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Estresse Fisiológico/efeitos dos fármacos , Transcriptoma/genética , Poluentes Químicos da Água/toxicidade
9.
Cytogenet Genome Res ; 158(3): 152-159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31272100

RESUMO

Among birds, species with the ZZ/ZW sex determination system generally show significant differences in morphology and size between the Z and W chromosomes (with the W usually being smaller than the Z). In the present study, we report for the first time the karyotype of the spot-flanked gallinule (Gallinula melanops) by means of classical and molecular cytogenetics. The spot-flanked gallinule has 2n = 80 (11 pairs of macrochromosomes and 29 pairs of microchromosomes) with an unusual W chromosome that is larger than the Z. Besides being totally heterochromatic, it has a secondary constriction in its long arm corresponding to the nucleolar organizer region, as confirmed by both silver staining and mapping of 18S rDNA probes. This is an unprecedented fact among birds. Additionally, 18S rDNA sites were also observed in 6 microchromosomes, while 5S rDNA was found in just 1 microchromosomal pair. Seven out of the 11 used microsatellite sequences were found to be accumulated in microchromosomes, and 6 microsatellite sequences were found in the W chromosome. In addition to the involvement of heterochromatin and repetitive DNAs in the differentiation of the large W chromosome, the results also show an alternative scenario that highlights the plasticity that shapes the evolutionary history of bird sex chromosomes.


Assuntos
Aves/genética , Evolução Molecular , Sequências Repetitivas de Ácido Nucleico/genética , Cromossomos Sexuais/genética , Animais , Bandeamento Cromossômico , Mapeamento Cromossômico , Feminino , Cariótipo , Repetições de Microssatélites/genética , Região Organizadora do Nucléolo/genética
10.
BMC Evol Biol ; 19(1): 139, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286867

RESUMO

BACKGROUND: Pathogens evolve in an arms race, frequently evolving virulence that defeats resistance genes in their hosts. Infection of multiple hosts may accelerate this virulence evolution. Theory predicts that host diversity affects pathogen diversity, with more diverse hosts expected to harbour more diverse pathogens that reproduce sexually. We tested this hypothesis by comparing the microsatellite (SSR) genetic diversity of the barley leaf pathogen Pyrenophora teres f. teres (Ptt) from barley (monoculture) and barley grass (outbreeding). We also aim to investigate host specificity and attempt to track virulence on two barley cultivars, Maritime and Keel. RESULTS: Genetic diversity in barley Ptt populations was higher than in populations from barley grass. Barley Ptt populations also had higher linkage disequilibrium levels, indicating less frequent sexual reproduction, consistent with the Red Queen hypothesis theory that genetically diverse hosts should select for higher levels of sexual reproduction of the pathogen. SSR analyses indicate that host-associated Ptt populations do not share genotypes and have independent evolutionary histories. Pathogenicity studies showed host specificity as host-associated Ptt isolates could not cross-infect hosts. Minimum spanning network analyses indicated two major clusters of barley Ptt. One cluster represents Maritime virulent and isolates from Western Australia (WA). Low PhiPt population differentiation between WA populations and those from Maritime and Keel, indicated a WA origin of the Maritime and Keel virulences. The main minimum spanning network cluster is represented by a panmictic population structure, represented by isolates from all over Australia. CONCLUSIONS: Although barley Ptt populations are more diverse than barley grass Ptt populations, this may be a result of the size and number of founder Ptt populations to Australia, with larger and more barley Ptt populations introduced. More frequent sexual reproduction of Ptt on barley grass support the Red Queen Hypothesis and suggest evolutionary potential of pathogens on diverse hosts are high. Extensive gene flow of Ptt between regions in Australia is suggested to maintain a panmictic population structure, with human-mediated dispersal aiding in virulence evolution of Ptt on barley.


Assuntos
Ascomicetos/genética , Ascomicetos/fisiologia , Evolução Molecular , Hordeum/microbiologia , Especificidade de Hospedeiro/genética , Doenças das Plantas/microbiologia , Genótipo , Desequilíbrio de Ligação , Repetições de Microssatélites/genética
11.
Neoplasma ; 66(6): 1002-1008, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31305125

RESUMO

Insulin-like growth factor 1 (IGF1) is implicated in normal cell growth. It has been reported that IGF1 has a mitogenic and anti-apoptotic effect on colorectal cancer cells. However, results of studies on the association between cytosine-adenine (CA) repeat polymorphism in IGF1 gene promoter and colorectal cancer (CRC) risk are inconsistent. We aimed to evaluate the association between CA repeat polymorphism and CRC risk, as well as the relationship with the clinicopathological characteristics of CRC and circulating IGF1 level in a native Chinese population. There were 734 participants who were native Chinese in this case-control study, including 367 CRC cases and 367 age- and sex-matched controls. CA repeat polymorphism was genotyped by PCR and fragment analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were evaluated by unconditional logistic regression analysis. Circulating level of IGF1 in cases was significantly higher than that in controls (P = 0.002), particularly in males. Less than 38 CA repeats were associated with decreased CRC risk after adjusting for age and sex (37 versus 38 CA repeats: OR = 0.45; 95%CI = 0.26-0.78), especially in males. (CA)18/19 genotype showed approximately half reduced CRC risk comparing to (CA)19/19 genotype (OR = 0.46; 95%CI = 0.25-0.85). There was a significant association between the sum of CA repeats and degree of differentiation of CRC (P = 0.044). We observed a trend that circulating level of IGF1 in individuals with CA ≤ 38 repeats was lower than that in individuals with CA > 38 repeats with a borderline statistically significance in overall and males. In conclusion, our findings support the possible role of CA repeat polymorphism in CRC risk.


Assuntos
Neoplasias Colorretais , Predisposição Genética para Doença , Fator de Crescimento Insulin-Like I , Repetições de Microssatélites , Regiões Promotoras Genéticas , Adenina , Estudos de Casos e Controles , China , Neoplasias Colorretais/genética , Citosina , Feminino , Humanos , Fator de Crescimento Insulin-Like I/genética , Masculino , Repetições de Microssatélites/genética , Regiões Promotoras Genéticas/genética
12.
Plant Dis ; 103(10): 2599-2605, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31339441

RESUMO

Tobacco black shank, caused by Phytophthora parasitica, is one of the most notorious tobacco diseases and causes huge economic losses worldwide. Understanding the genetic variation of P. parasitica populations is essential to the development of disease control measures. In this research, 210 simple sequence repeat (SSR) markers for P. parasitica were identified, 10 of which were polymorphic among nine reference strains. We further performed population genetic analysis of 245 P. parasitica isolates randomly collected from tobacco fields in Chongqing for mating type, molecular variation at 14 SSR loci (four of which were identified previously), and sensitivity to the fungicide metalaxyl. The results showed that the A2 mating type was dominant and no A1 mating type isolate was discovered. SSR genotyping distinguished 245 P. parasitica isolates into 46 genotypes, four of which were dominant in the population. Low genotypic diversity and excess heterozygosity were common in nearly all of the populations from Chongqing. Population analysis showed that no differentiation existed among different populations. All isolates tested were highly sensitive to metalaxyl. Taken together, our results showed that the P. parasitica populations from tobacco fields in Chongqing belonged to a clonal lineage and were highly sensitive to metalaxyl.


Assuntos
Genética Populacional , Phytophthora , Tabaco , Alanina/análogos & derivados , Alanina/farmacologia , China , Genótipo , Repetições de Microssatélites/genética , Phytophthora/efeitos dos fármacos , Phytophthora/genética , Tabaco/parasitologia
13.
Jpn J Clin Oncol ; 49(7): 620-627, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220306

RESUMO

OBJECTIVE: Recurrent hydatidiform moles are reportedly biparental complete moles and related to mutated NLRP7 and KHDC3L. This study was designed to identify mutations of gene NLRP7 and KHDC3L in biparental complete moles. METHODS: In this study, we have screened NLRP7 and KHDC3L mutations in five patients with recurrent moles and five with sporadic moles. Molar tissues and blood samples were collected from patients and their partners. Genotypes of the molar tissues were determined based on short tandem repeat polymorphism. The coding exons of NLRP7 and KHDC3L were sequenced. RESULTS: Two patients with recurrent moles had biparental complete moles, while all other patients had androgenetic complete moles. Three non-synonymous variants in NLRP7 (c.955 G>A, c.1280 T>C and c.1441 G>A) and one in KHDC3L (c.602 C>G) were identified in patients with recurrent moles. NLRP7 c.1441 G>A and c.1280 T>C were mutations found in the Chinese population, while c.1441 G>A was only detected in patients with biparental complete moles in this study. CONCLUSIONS: Genotyping can be used to differentiate biparental complete moles from androgenetic moles and to predict the risk of recurrent moles in future pregnancies. NLRP7 c.1441 G>A may associate with biparental complete moles. Biparental complete moles exhibit genetic heterogeneity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Grupo com Ancestrais do Continente Asiático/genética , Mola Hidatiforme/genética , Mutação/genética , Recidiva Local de Neoplasia/genética , Proteínas/genética , Neoplasias Uterinas/genética , Adulto , Sequência de Bases , Feminino , Humanos , Mola Hidatiforme/patologia , Masculino , Repetições de Microssatélites/genética , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Gravidez
14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(6): 676-681, 2019 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-31238618

RESUMO

Objective: To study the molecular-epidemiological characteristics of Brucella species isolated from different countries, using the multiple locus tandem-repeat (MLVA) analysis. Methods: Eleven variable-number tandem-repeat (VNTR) loci were selected. VNTR strains of Brucella isolated from 48 different countries in 1953-2013, were analyzed by using the BioNumerics software. Unweighted Paired Arithmetic Average method was used to cluster and draw phylogenetic tree as well as the minimum spannin. Results: The evolutionary relationship of Brucella phylogenetic tree was consistent with the classical biological typing method. However, the Brucella suis biovar 5 strains were different from the other Brucella suis biovars 1, 2, 3 and 4. Brucella ceti strains were divided into two parts and different from each other. Worldwide epidemics of brucellosis were emerged from 2005 to 2008 under the MLVA11 Orsay analysis. China has been a brucellosis-prone regions, with Brucella melitensis as the main epidemic Brucella species, followed by Brucella abortus. Brucella suis was mainly identified in the southern provinces, but Brucella canis was mainly found in dogs. No human cases were found. Conclusion: Molecular-epidemiological characteristics of the Brucella strains were related to factors as time, region and hosts of isolation, which are important to setting up prevention and control programs on brucellosis.


Assuntos
Brucella/genética , Brucella/isolamento & purificação , Brucelose/epidemiologia , Tipagem de Sequências Multilocus/métodos , Brucella/classificação , Brucelose/diagnóstico , Brucelose/microbiologia , China , DNA Bacteriano/genética , Loci Gênicos , Genótipo , Humanos , Repetições de Microssatélites/genética , Repetições Minissatélites/genética , Epidemiologia Molecular , Filogenia , Sequências de Repetição em Tandem
15.
Parasitol Res ; 118(7): 2257-2262, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31177405

RESUMO

The New England cottontail rabbit (NEC, Sylvilagus transitionalis) population has decreased dramatically in New York, USA, and the role of parasites in limiting the population has never been examined. The closely related and sympatric eastern cottontail rabbit (EC, Sylvilagus floridanus) was introduced into the range of NEC by humans and is currently thriving. This study aimed to investigate gastrointestinal parasites of the NEC and the EC and compare their parasite communities. Fecal pellets from 195 NEC and 125 EC were collected from the Hudson Valley, New York, in the winter of 2013-2014. Centrifugal fecal floats were performed in Sheather's sugar solution, and parasite ova and cysts were examined microscopically to identify gastrointestinal parasites present. For all pellets combined (n = 320), 91% were found to harbor at least 1 parasite species, with Eimeria species being the most common. Genetic analysis of pellets using microsatellite DNA identified 248 individual rabbits, with parasite prevalence (94%) similar to the prevalence estimate based on all pellets (91%). EC samples had a significantly higher (p < 0.05) parasite species richness (1.73, range 0-4) than NEC (1.20, range 0-3). EC and NEC shared 3 moderate to high (9-89%) prevalence parasites, in which EC prevalence was consistently higher. One parasite species was only found in NEC, and two were only found in EC, but the majority of these were of low abundance, precluding further statistical analyses.


Assuntos
Coccidiose/veterinária , Eimeria/classificação , Enteropatias Parasitárias/veterinária , Repetições de Microssatélites/genética , Parasitos/classificação , Coelhos/parasitologia , Animais , Coccidiose/epidemiologia , Coccidiose/parasitologia , Eimeria/genética , Eimeria/isolamento & purificação , Meio Ambiente , Fezes/parasitologia , Feminino , Geografia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , New York/epidemiologia , Óvulo , Parasitos/genética , Parasitos/isolamento & purificação , Dinâmica Populacional , Inquéritos e Questionários , Simpatria
16.
Phytopathology ; 109(10): 1779-1792, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31179858

RESUMO

Colletotrichum tanaceti, the causal agent of anthracnose, is an emerging pathogen of commercially grown pyrethrum (Tanacetum cinerariifolium) in Australia. A microsatellite marker library was developed to understand the spatio-genetic structure over three sampled years and across two regions where pyrethrum is cultivated in Australia. Results indicated that C. tanaceti was highly diverse with a mixed reproductive mode; comprising both sexual and clonal reproduction. Sexual reproduction of C. tanaceti was more prevalent in Tasmania than in Victoria. Little differentiation was observed among field populations likely due to isolation by colonization but most of the genetic variation was occurring within populations. C. tanaceti was likely to have had a long-distance gene and genotype flow among distant populations within a state and between states. Anthropogenic transmission of propagules and wind dispersal of ascospores are the most probable mechanisms of long-distance dispersal of C. tanaceti. Evaluation of putative population histories suggested that C. tanaceti most likely originated in Tasmania and expanded from an unidentified host onto pyrethrum. Victoria was later invaded by the Tasmanian population. With the mixed mode of reproduction and possible long-distance gene flow, C. tanaceti is likely to have a high evolutionary potential and thereby has ability to adapt to management practices in the future.


Assuntos
Evolução Biológica , Chrysanthemum cinerariifolium , Colletotrichum , Variação Genética , Austrália , Chrysanthemum cinerariifolium/microbiologia , Colletotrichum/genética , Colletotrichum/fisiologia , Fluxo Gênico , Repetições de Microssatélites/genética , Doenças das Plantas , Tasmânia
17.
BMC Evol Biol ; 19(1): 115, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31170910

RESUMO

BACKGROUND: Many species of social insects have large-scale mating and dispersal flights and their populations are therefore often relatively homogenous. In contrast, dispersal on the wing appears to be uncommon in most species of the ant genus Cardiocondyla, because its males are wingless and the winged queens mate in their natal nests before dispersing on foot. Here we examine the population structure of C. venustula from South Africa. This species is of particular interest for the analysis of life history evolution in Cardiocondyla, as it occupies a phylogenetic position between tropical species with multi-queen (polygynous) colonies and fighting males and a Palearctic clade with single-queen colonies and mutually peaceful males. Males of C. venustula exhibit an intermediate strategy between lethal fighting and complete tolerance - they mostly engage in non-lethal fights and defend small territories inside their natal nests. We investigated how this reproductive behavior influences colony and population structure by analyzing samples on two geographic scales in South Africa: a small 40 × 40m2 plot and a larger area with distances up to 5 km between sampling sites in Rietvlei Nature Reserve near Pretoria. RESULTS: Colonies were found to be facultatively polygynous and queens appear to mate only with a single male. The extraordinarily high inbreeding coefficient suggests regular sib-mating. Budding by workers and young queens is the predominant mode of colony-founding and leads to high population viscosity. In addition, some queens appear to found colonies independently or through adoption into foreign nests. CONCLUSION: While C. venustula resembles tropical Cardiocondyla in queen number and mating frequency, it differs by the absence of winged disperser males. Dispersal by solitary, mated queens on foot or by short flights and their adoption by alien colonies might promote gene flow between colonies and counteract prolonged inbreeding. The abundance of suitable habitat and the high density of nests facilitate the spread of this species by budding and together with the apparent resistance against inbreeding make it a highly successful pioneer species and invader of degraded and man-made habitats.


Assuntos
Formigas/fisiologia , Territorialidade , Alelos , Animais , Formigas/genética , DNA Mitocondrial/genética , Feminino , Haplótipos/genética , Heterozigoto , Masculino , Repetições de Microssatélites/genética , Filogenia , Dinâmica Populacional , Comportamento Sexual Animal , África do Sul
18.
BMC Evol Biol ; 19(1): 118, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185884

RESUMO

BACKGROUND: There is a biogeographic break located at 30°S in the southeast Pacific, in a coastal area of strong environmental discontinuities. Several marine benthic taxa with restricted dispersal have a coincident phylogeographic break at 30°S, indicating that genetic structure is moulded by life history traits that limit gene flow and thereby promote divergence and speciation. In order to evaluate intraspecific divergence at this biogeographic break, we investigated the genetic and morphological variation of the directly developing beach isopod Excirolana hirsuticauda along 1900 km of the southeast Pacific coast, across 30°S. RESULTS: The COI sequences and microsatellite data both identified a strong discontinuity between populations of E. hirsuticauda to the north and south of 30°S, and a second weaker phylogeographic break at approximately 35°S. The three genetic groups were evidenced by different past demographic and genetic diversity signatures, and were also clearly distinguished with microsatellite data clustering. The COI sequences established that the genetic divergence of E. hirsuticauda at 30°S started earlier than divergence at 35°. Additionally, the three groups have different past demographic signatures, with probable demographic expansion occurring earlier in the southern group (south of 35°S), associated with Pleistocene interglacial periods. Interestingly, body length, multivariate morphometric analyses, and the morphology of a fertilization-related morphological character in males, the appendix masculina, reinforced the three genetic groups detected with genetic data. CONCLUSIONS: The degree of divergence of COI sequences, microsatellite data, and morphology was concordant and showed two geographic areas in which divergence was promoted at differing historical periods. Variation in the appendix masculina of males has probably promoted reproductive isolation. This variation together with gene flow restrictions promoted by life history traits, small body size, oceanographic discontinuities and sandy-beach habitat continuity, likely influenced species divergence at 30°S in the southeast Pacific coast. The degree of genetic and morphological differentiation of populations to the north and south of 30°S suggests that E. hirsuticauda harbours intraspecific divergence consistent with reproductive isolation and an advanced stage of speciation. The speciation process within E. hirsuticauda has been shaped by both restrictions to gene flow and a prezygotic reproductive barrier.


Assuntos
Isópodes/anatomia & histologia , Isópodes/genética , Filogeografia , Análise de Variância , Animais , Teorema de Bayes , Tamanho Corporal , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fluxo Gênico , Loci Gênicos , Variação Genética , Haplótipos/genética , Isópodes/classificação , Repetições de Microssatélites/genética , Filogenia , Análise de Componente Principal
19.
BMC Evol Biol ; 19(1): 119, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185889

RESUMO

BACKGROUND: The evolution of male pregnancy is the most distinctive characteristic of syngnathids, and their specialized life history traits make syngnathid species excellent model species for many issues in biological evolution. However, the origin of syngnathids and the evolutionary divergence time of different syngnathid species remain poorly resolved. Comprehensive phylogenetic studies of the Syngnathidae will provide critical evidence to elucidate their origin, evolution, and dispersal patterns. RESULTS: We sequenced the mitochondrial genomes of eight syngnathid species in this study, and the estimated divergence times suggested that syngnathids diverged from other teleosts approximately 48.8 Mya during the Eocene period. Selection analysis showed that many mitochondrial genes of syngnathids exhibited significantly lower Ka/Ks values than those of other teleosts. The two most frequently used codons in syngnathid fishes were different from those in other teleosts, and a greater proportion of the mitochondrial simple sequence repeats (SSRs) were distributed in non-coding sequences in syngnathids compared with other teleosts. CONCLUSIONS: Our study indicated that syngnathid fishes experienced an adaptive radiation process during the early explosion of species. Syngnathid mitochondrial OXPHOS genes appear to exhibit depressed Ka/Ks ratios compared with those of other teleosts, and this may suggest that their mitogenomes have experienced strong selective constraints to eliminate deleterious mutations.


Assuntos
Adaptação Fisiológica/genética , Evolução Biológica , Peixes/genética , Genoma Mitocondrial , Smegmamorpha/genética , Animais , Códon/genética , Simulação por Computador , Feminino , Genes Mitocondriais , Variação Genética , Geografia , Masculino , Repetições de Microssatélites/genética , Nucleotídeos/genética , Filogenia , Seleção Genética , Especificidade da Espécie , Fatores de Tempo
20.
Leg Med (Tokyo) ; 39: 45-48, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31207384

RESUMO

Genetic polymorphism of 21 autosomal STR loci included in Goldeneye™ DNA ID 22NC Kit (D19S253, D6S477, D22GATA198B05, D15S659, D8S1132, D3S1358, D3S3045, D14S608, D17S1290, D3S1744, D2S411, D18S535, D13S325, D7S1517, D10S1435, D11S2368, D4S2366, D1S1656, D7S3048, D10S1248 and D5S2500) was studied in 297 unrelated She individuals. Allele frequencies and forensic efficiency parameters such as, observed and expected heterozygosity (Ho & He), matching probability (MP), power of discrimination (PD), polymorphism information content (PIC), power of exclusion (PE), typical paternity index (TPI) was calculated for the loci. The combined PD and PE for all 21 STR loci were calculated to be 0.999999999999999999999999324094 and 0.999999996182425, respectively. The dataset indicated the usefulness of these loci in personal identification, parentage testing and complex kinship analysis in She population. The MDS plots and neighbor-joining tree were constructed based on pair-wise Nei's genetic distance by comparing allele frequency data for the 21 loci with ten other populations. The analysis showed that She population lies closer to a clade consisting Southern Han, Hainan Han and Li populations.


Assuntos
Cromossomos Humanos Par 21/genética , Impressões Digitais de DNA/métodos , Genética Forense/métodos , Loci Gênicos/genética , Genética Populacional/métodos , Repetições de Microssatélites/genética , Grupo com Ancestrais do Continente Asiático/genética , China , Frequência do Gene , Humanos
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