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2.
Front Plant Sci ; 13: 1059817, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36523628

RESUMEN

Long-term conservation of Plant Genetic Resources (PGR) is a key priority for guaranteeing food security and sustainability of agricultural systems for current and future generations. The need for the secure conservation of genetic resources collections ex situ is critical, due to rapid and extreme climatic changes which are threatening and reducing biodiversity in their natural environments. The International Potato Center (CIP) conserves one of the most complete and diverse genetic resources collections of potato, with more than 7500 accessions composed of 4900 cultivated potato and 2600 potato wild relative accessions. The clonal conservation of cultivated potato, principally landraces, through in vitro or field collections is indispensable to maintain fixed allelic states, yet it is costly and labor-intensive. Cryopreservation, the conservation of biological samples in liquid nitrogen (-196°C), is considered the most reliable and cost-efficient long-term ex-situ conservation method for clonal crops. Over the last decade, CIP has built one of the largest potato cryobanks worldwide, cyopreserving more than 4000 cultivated potato accessions which represents 84% of the total cultivated potato collection currently conserved at CIP. In approximately, four years the entire potato collection will be cryopreserved. The development of an applied, robust cryopreservation protocol for potato, serves as a model for other clonally maintained crop collections. The CIP cryobank designs experiments with a high number of genetically diverse genotypes (70-100 accessions, seven cultivated species), to obtain reliable results that can be extrapolated over the collection as genotypes can often respond variably to the same applied conditions. Unlike most published reports on cryopreservation of plants, these large-scale experiments on potato are unique as they examine the acclimatization process of in vitro plants prior to, as well as during cryopreservation on up to ten times the number of genotypes conventionally reported in the published literature. As a result, an operational cryopreservation protocol for potato has advanced that works well across diverse potato accessions, not only with reduced processing time and costs, but also with an increased average full-plant recovery rate from 58% to 73% (+LN) for routine cryopreservation. The present article describes the composition of CIP's cryobank, the cryopreservation protocol, methodology for the dynamic improvement of the operational protocol, as well as data collected on regeneration from long term cryopreserved potatoes.

3.
Front Plant Sci ; 13: 934296, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35898221

RESUMEN

Pigeonpea, a climate-resilient legume, is nutritionally rich and of great value in Asia, Africa, and Caribbean regions to alleviate malnutrition. Assessing the grain nutrient variability in genebank collections can identify potential sources for biofortification. This study aimed to assess the genetic variability for grain nutrients in a set of 600 pigeonpea germplasms conserved at the RS Paroda Genebank, ICRISAT, India. The field trials conducted during the 2019 and 2020 rainy seasons in augmented design with four checks revealed significant differences among genotypes for all the agronomic traits and grain nutrients studied. The germplasm had a wider variation for agronomic traits like days to 50% flowering (67-166 days), days to maturity (112-213 days), 100-seed weight (1.69-22.17 g), and grain yield per plant (16.54-57.93 g). A good variability was observed for grain nutrients, namely, protein (23.35-29.50%), P (0.36-0.50%), K (1.43-1.63%), Ca (1,042.36-2,099.76 mg/kg), Mg (1,311.01-1,865.65 mg/kg), Fe (29.23-40.98 mg/kg), Zn (24.14-35.68 mg/kg), Mn (8.56-14.01 mg/kg), and Cu (7.72-14.20 mg/kg). The germplasm from the Asian region varied widely for grain nutrients, and the ones from African region had high nutrient density. The significant genotype × environment interaction for most of the grain nutrients (except for P, K, and Ca) indicated the sensitivity of nutrient accumulation to the environment. Days to 50% flowering and days to maturity had significant negative correlation with most of the grain nutrients, while grain yield per plant had significant positive correlation with protein and magnesium, which can benefit simultaneous improvement of agronomic traits with grain nutrients. Clustering of germplasms based on Ward.D2 clustering algorithm revealed the co-clustering of germplasm from different regions. The identified top 10 nutrient-specific and 15 multi-nutrient dense landraces can serve as promising sources for the development of biofortified lines in a superior agronomic background with a broad genetic base to fit the drylands. Furthermore, the large phenotypic data generated in this study can serve as a raw material for conducting SNP/haplotype-based GWAS to identify genetic variants that can accelerate genetic gains in grain nutrient improvement.

4.
Nat Plants ; 8(5): 491-499, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35534721

RESUMEN

Crop landraces have unique local agroecological and societal functions and offer important genetic resources for plant breeding. Recognition of the value of landrace diversity and concern about its erosion on farms have led to sustained efforts to establish ex situ collections worldwide. The degree to which these efforts have succeeded in conserving landraces has not been comprehensively assessed. Here we modelled the potential distributions of eco-geographically distinguishable groups of landraces of 25 cereal, pulse and starchy root/tuber/fruit crops within their geographic regions of diversity. We then analysed the extent to which these landrace groups are represented in genebank collections, using geographic and ecological coverage metrics as a proxy for genetic diversity. We find that ex situ conservation of landrace groups is currently moderately comprehensive on average, with substantial variation among crops; a mean of 63% ± 12.6% of distributions is currently represented in genebanks. Breadfruit, bananas and plantains, lentils, common beans, chickpeas, barley and bread wheat landrace groups are among the most fully represented, whereas the largest conservation gaps persist for pearl millet, yams, finger millet, groundnut, potatoes and peas. Geographic regions prioritized for further collection of landrace groups for ex situ conservation include South Asia, the Mediterranean and West Asia, Mesoamerica, sub-Saharan Africa, the Andean mountains of South America and Central to East Asia. With further progress to fill these gaps, a high degree of representation of landrace group diversity in genebanks is feasible globally, thus fulfilling international targets for their ex situ conservation.


Asunto(s)
Productos Agrícolas , Fitomejoramiento , Productos Agrícolas/genética , Asia Oriental , América del Sur , Triticum/genética
5.
Front Plant Sci ; 12: 692463, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34489996

RESUMEN

Finger millet [Eleusine coracana (L.) Gaertn.] is an important climate-resilient nutrient-dense crop grown as a staple food grain in Asia and Africa. Utilizing the full potential of the crop mainly depends on an in-depth exploration of the vast diversity in its germplasm. In this study, the global finger millet germplasm diversity panel of 314 accessions was genotyped, using the DArTseq approach to assess genetic diversity and population structure. We obtained 33,884 high-quality single nucleotide polymorphism (SNP) markers on 306 accessions after filtering. Finger millet germplasm showed considerable genetic diversity, and the mean polymorphic information content, gene diversity, and Shannon Index were 0.110, 0.114, and 0.194, respectively. The average genetic distance of the entire set was 0.301 (range 0.040 - 0.450). The accessions of the race elongata (0.326) showed the highest average genetic distance, and the least was in the race plana (0.275); and higher genetic divergence was observed between elongata and vulgaris (0.320), while the least was between compacta and plana (0.281). An average, landrace accessions had higher gene diversity (0.144) and genetic distance (0.299) than the breeding lines (0.117 and 0.267, respectively). A similar average gene diversity was observed in the accessions of Asia (0.132) and Africa (0.129), but Asia had slightly higher genetic distance (0.286) than African accessions (0.276), and the distance between these two regions was 0.327. This was also confirmed by a model-based STRUCTURE analysis, genetic distance-based clustering, and principal coordinate analysis, which revealed two major populations representing Asia and Africa. Analysis of molecular variance suggests that the significant population differentiation was mainly due to within individuals between regions or between populations while races had a negligible impact on population structure. Finger millet diversity is structured based on a geographical region of origin, while the racial structure made negligible contribution to population structure. The information generated from this study can provide greater insights into the population structure and genetic diversity within and among regions and races, and an understanding of genomic-assisted finger millet improvement.

6.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-34518223

RESUMEN

The narrow genetics of most crops is a fundamental vulnerability to food security. This makes wild crop relatives a strategic resource of genetic diversity that can be used for crop improvement and adaptation to new agricultural challenges. Here, we uncover the contribution of one wild species accession, Arachis cardenasii GKP 10017, to the peanut crop (Arachis hypogaea) that was initiated by complex hybridizations in the 1960s and propagated by international seed exchange. However, until this study, the global scale of the dispersal of genetic contributions from this wild accession had been obscured by the multiple germplasm transfers, breeding cycles, and unrecorded genetic mixing between lineages that had occurred over the years. By genetic analysis and pedigree research, we identified A. cardenasii-enhanced, disease-resistant cultivars in Africa, Asia, Oceania, and the Americas. These cultivars provide widespread improved food security and environmental and economic benefits. This study emphasizes the importance of wild species and collaborative networks of international expertise for crop improvement. However, it also highlights the consequences of the implementation of a patchwork of restrictive national laws and sea changes in attitudes regarding germplasm that followed in the wake of the Convention on Biological Diversity. Today, the botanical collections and multiple seed exchanges which enable benefits such as those revealed by this study are drastically reduced. The research reported here underscores the vital importance of ready access to germplasm in ensuring long-term world food security.


Asunto(s)
Arachis/genética , Productos Agrícolas/genética , Semillas/genética , África , Asia , Mapeo Cromosómico/métodos , ADN de Plantas/genética , Marcadores Genéticos/genética , Variación Genética/genética , Genoma de Planta/genética , Hibridación Genética/genética , Oceanía , Fitomejoramiento/métodos , Especificidad de la Especie
7.
Front Plant Sci ; 12: 571243, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34267766

RESUMEN

Information on photoperiod and temperature sensitivity of sorghum germplasm is important to identify appropriate sources for developing cultivars with a broad adaptation. The sorghum mini core collection consisting of 242 accessions along with three control cultivars were evaluated for days to 50% flowering (DFL) and plant height in two long-day rainy and two short-day post-rainy seasons, and for grain yield and 100-seed weight in the two post-rainy seasons. Differences in DFL and cumulative growing degree days (CGDD) in the rainy and post-rainy seasons were used to classify the accessions for photoperiod and temperature sensitivity. Results revealed 18 mini core landraces as photoperiod and temperature insensitive (PTINS), 205 as photoperiod sensitive and temperature insensitive (PSTINS), and 19 as photoperiod and temperature-sensitive (PTS) sources. The 19 PTS sources and 80 PSTINS sources took less DFL in the long-day rainy seasons than in the short-day post-rainy season indicating their adaptation to the rainy season and a possible different mechanism than that trigger flowering in the short-day sorghums. In all three groups, several accessions with desirable combinations of agronomic traits were identified for use in the breeding programs to develop climate-resilient cultivars and for genomic studies to identify genes responsible for the photoperiod and temperature responses.

8.
J Exp Bot ; 72(14): 5158-5179, 2021 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-34021317

RESUMEN

The CGIAR crop improvement (CI) programs, unlike commercial CI programs, which are mainly geared to profit though meeting farmers' needs, are charged with meeting multiple objectives with target populations that include both farmers and the community at large. We compiled the opinions from >30 experts in the private and public sector on key strategies, methodologies, and activities that could the help CGIAR meet the challenges of providing farmers with improved varieties while simultaneously meeting the goals of: (i) nutrition, health, and food security; (ii) poverty reduction, livelihoods, and jobs; (iii) gender equality, youth, and inclusion; (iv) climate adaptation and mitigation; and (v) environmental health and biodiversity. We review the crop improvement processes starting with crop choice, moving through to breeding objectives, production of potential new varieties, selection, and finally adoption by farmers. The importance of multidisciplinary teams working towards common objectives is stressed as a key factor to success. The role of the distinct disciplines, actors, and their interactions throughout the process from crop choice through to adoption by farmers is discussed and illustrated.


Asunto(s)
Agricultura , Agricultores , Humanos
9.
Front Plant Sci ; 11: 587426, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33381130

RESUMEN

Germplasm should be conserved in such a way that the genetic integrity of a given accession is maintained. In most genebanks, landraces constitute a major portion of collections, wherein the extent of genetic diversity within and among landraces of crops vary depending on the extent of outcrossing and selection intensity infused by farmers. In this study, we assessed the level of diversity within and among 108 diverse landraces and wild accessions using both phenotypic and genotypic characterization. This included 36 accessions in each of sorghum, pearl millet, and pigeonpea, conserved at ICRISAT genebank. We genotyped about 15 to 25 individuals within each accession, totaling 1,980 individuals using the DArTSeq approach. This resulted in 45,249, 19,052, and 8,211 high-quality single nucleotide polymorphisms (SNPs) in pearl millet, sorghum, and pigeonpea, respectively. Sorghum had the lowest average phenotypic (0.090) and genotypic (0.135) within accession distances, while pearl millet had the highest average phenotypic (0.227) and genotypic (0.245) distances. Pigeonpea had an average of 0.203 phenotypic and 0.168 genotypic within accession distances. Analysis of molecular variance also confirms the lowest variability within accessions of sorghum (26.3%) and the highest of 80.2% in pearl millet, while an intermediate in pigeonpea (57.0%). The effective sample size required to capture maximum variability and to retain rare alleles while regeneration ranged from 47 to 101 for sorghum, 155 to 203 for pearl millet, and 77 to 89 for pigeonpea accessions. This study will support genebank curators, in understanding the dynamics of population within and among accessions, in devising appropriate germplasm conservation strategies, and aid in their utilization for crop improvement.

10.
Front Microbiol ; 11: 572381, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33193170

RESUMEN

The human T-lymphotropic virus (HTLV) is part of the group of retroviruses that share similar routes of transmission to the human immunodeficiency virus (HIV). Coinfection of these viruses can affect the clinical course of both infections, and reports have shown a quicker progression to AIDS and the development of HIV-related opportunistic infections. The current study investigated the demographic characteristics, prevalence, and the subtypes of HTLV among people living with HIV/AIDS (PLWHA) in the State of Pará, Northern Brazil. Blood samples were obtained from patients who were attending a reference unit that provides medical assistance to HIV-infected individuals in the State of Pará, Brazil, during the period of May 2016 to June 2017. Plasma samples were screened by ELISA tests to detect antibodies anti-HTLV-1/2. DNA and viral types were identified by real-time polymerase chain reaction (qPCR). All samples with viral DNA were submitted to nested PCR and nucleotide sequencing. The overall coinfection rate was 1.4% (5/368), and all samples were from subtype HTLV-1a. No cases of HTLV-2 infection were detected. The prevalence of HTLV-1 was higher in females (80%), individuals between 31 and 50 years of age, heterosexual, unmarried, with low monthly income, with secondary educational level or higher, sporadic condom usage, limited number of sexual partners, and no history of sexually transmitted infections. All samples from HTLV-1-infected patients were identified as strains belonging to the subtype 1a (Cosmopolitan), subgroup A (Transcontinental). This study identified that the prevalence of HIV/HTLV coinfection has dropped from 8 to 1.3% in the current investigation. There was a shift of HTLV subtype from a predominance of HTLV-2 infection in the past to an actual exclusively HTLV-1a. There was no significant association between economic, sociodemographic, and behavioral characteristics in HIV/HTLV coinfection.

11.
Virus Evol ; 6(2): veaa053, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33133639

RESUMEN

The description of the first human retrovirus, human T-lymphotropic virus 1 (HTLV-1), was soon associated with an aggressive lymphoma and a chronic inflammatory neurodegenerative disease. Later, other associated clinical manifestations were described, affecting diverse target organs in the human body and showing the enormous burden carried by the virus and the associated diseases. The epidemiology of HTLV-1 and HTLV-2 showed that they were largely distributed around the world, although it is possible to locate geographical areas with pockets of low and very high prevalence and incidence. Aboriginal Australians and indigenous peoples of Brazil are examples of the large spread of HTLV-1 and HTLV-2, respectively. The epidemiological link of both situations is their occurrence among isolated, epidemiologically closed or semi-closed communities. The origin of the viruses in South America shows two different branches with distinct timing of entry. HTLV-1 made its probable entrance in a more recent route through the east coast of Brazil at the beginning of the slave trade from the African continent, starting in the 16th century and lasting for more than 350 years. HTLV-2 followed the ancient route of human migration from the Asian continent, crossing the Behring Strait and then splitting in South America as the population became separated by the Andes Mountains. By that time, HTLV-2c probably arose and became isolated among the indigenous populations in the Brazilian Amazon. The study of epidemiologically closed communities of indigenous populations in Brazil allowed tracing the most likely route of entry, the generation of a new molecular subtype (HTLV-2c), the elucidation of the vertical transmission of HTLV-2, the intrafamilial aggregation of cases and the escape and spread of the virus to other areas in Brazil and abroad. Despite the burden and impact of both viruses, they are maintained as silent infections among human populations because 1, health authorities in most South American countries in which national surveillance is poor have little interest in the disease, 2, the information is commonly lost as indigenous groups do not have specific policies for HTLV and other sexually transmitted infections, and 3, health access is not feasible or properly delivered.

12.
Plants (Basel) ; 9(10)2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33019539

RESUMEN

The international collections of plant genetic resources for food and agriculture (PGRFA) hosted by 11 CGIAR Centers are important components of the United Nations Food and Agriculture Organization's global system of conservation and use of PGRFA. They also play an important supportive role in realizing Target 2.5 of the Sustainable Development Goals. This paper analyzes CGIAR genebanks' trends in acquiring and distributing PGRFA over the last 35 years, with a particular focus on the last decade. The paper highlights a number of factors influencing the Centers' acquisition of new PGRFA to include in the international collections, including increased capacity to analyze gaps in those collections and precisely target new collecting missions, availability of financial resources, and the state of international and national access and benefit-sharing laws and phytosanitary regulations. Factors contributing to Centers' distributions of PGRFA included the extent of accession-level information, users' capacity to identify the materials they want, and policies. The genebanks' rates of both acquisition and distribution increased over the last decade. The paper ends on a cautionary note concerning the potential of unresolved tensions regarding access and benefit sharing and digital genomic sequence information to undermine international cooperation to conserve and use PGRFA.

13.
PLoS One ; 15(5): e0232783, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32369533

RESUMEN

INTRODUCTION: Human pegivirus 1 (HPgV-1) is a single-stranded, positive-sense RNA virus belonging to the Flaviviridae family with limited cause-effect evidence of the causation of human diseases. However, studies have shown a potential beneficial impact of HPgV-1 coinfection in HIV disease progression. Human T lymphotropic virus-1 (HTLV-1) is a retrovirus known for causing diseases, especially in muscle and white blood cells, in approximately 5% of patients. Thus, this study aimed to investigate the potential effects of an HPgV-1 infection in patients carrying HTLV-1 in the state of Pará in the North Region of Brazil. METHODS: A group of HTLV-1 carriers was compared to healthy controls. Blood samples were collected, data from medical regards were collected, and a questionnaire was administered. HPgV-1 and HTLV-1 positivity was determined by quantitative polymerase chain reaction (qRT-PCR). The data were analyzed to correlate the effects of HPgV-1 coinfection in HTLV-1 carriers. RESULTS: A total of 158 samples were included in the study: 74 HTLV-1-positive patients (46,8%) and 84 healthy controls (53,2%). The overall HPgV-1 positivity rate was 7.6% (12/158), resulting in a prevalence of 5.4% (4/74) and 9.5% (8/84) in HTLV-1 carriers and healthy controls, respectively. No significant differences were found when comparing any clinical or demographic data between groups. CONCLUSION: This study indicated that the prevalence of HPgV-1 infection is low in HTLV-1 carriers in Belém, Pará, and probably does not alter the clinical course of HTLV-1 infection, however, further studies are still needed.


Asunto(s)
Coinfección/complicaciones , Infecciones por Flaviviridae/complicaciones , Infecciones por HTLV-I/complicaciones , Adulto , Brasil/epidemiología , Coinfección/epidemiología , Femenino , Flaviviridae/aislamiento & purificación , Infecciones por Flaviviridae/epidemiología , Infecciones por HTLV-I/epidemiología , Virus Linfotrópico T Tipo 1 Humano/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
14.
Front Microbiol ; 11: 99, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32117129

RESUMEN

Pseudocercospora musae, causal agent of Sigatoka leaf spot, or yellow Sigatoka disease, is considered a major pathogen of banana (Musa spp.). Widely disseminated in Brazil, this study explored the genetic diversity in field populations of the pathogen from production areas in the Distrito Federal and the States of Bahia, Minas Gerais, and Rio Grande do Norte. Resistance to demethylation inhibitor (DMI) fungicides was also examined. For 162 isolates from 10 banana growing regions, analysis of mating type idiomorph frequency was conducted, together with estimation of genetic diversity at 15 microsatellite loci. A total of 149 haplotypes were identified across the examined populations, with an average genetic diversity of 4.06. In general, populations displayed 1:1 proportions of idiomorphs MAT1-1 and MAT1-2, providing evidence for sexual recombination. Multilocus linkage disequilibrium also indicated asexual reproduction contributing to the genetic structure of certain populations. AMOVA revealed that 86.3% of the genetic differentiation of the pathogen occurred among isolates within populations. Discriminant Analysis of Principal Components (DAPC) identified six most probable genetic groups, with no population structure associated with geographic origin or collection site. Although genetic similarity was observed among certain populations from different states, data revealed increasing genetic differentiation with increasing geographic distance, as validated by Mantel's test (r = 0.19, P < 0.001). On the basis of DMI fungicide sensitivity testing and CYP51 gene sequence polymorphism, isolates from the Distrito Federal separated into two main groups, one with generally higher EC50 values against eight DMI fungicides. A clear phenotype-to-genotype relationship was observed for isolates carrying the CYP51 alteration Y461N. Conventionally adopted fungicides for control of Sigatoka leaf spot are likely to be overcome by combined sexual and asexual reproduction mechanisms in P. musae driving genetic variability. Continued analysis of pathogen genetic diversity and monitoring of DMI sensitivity profiles of Brazilian field populations is essential for the development of integrated control strategies based on host resistance breeding and rational design of fungicide regimes.

15.
BMC Infect Dis ; 20(1): 129, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-32046662

RESUMEN

BACKGROUND: Syphilis is a sexually transmitted infection (STI) transmitted from person to person mainly by sexual intercourse or through vertical transmission during pregnancy. Female sex workers (FSWs) are exposed especially to syphilis infection, and besides all the efforts to control the spread of STIs, syphilis prevalence is still rising, mainly occurring in low-income countries. This study aimed to investigate the syphilis prevalence, demographic characteristics and sexual habits among FSWs in the Amazon region of Brazil. METHODS: A cross-sectional study was carried out including 184 FSWs from 3 countryside cities of the state of Pará, Amazon region of Brazil. A venereal disease research laboratory test and an indirect immunoenzyme assay to test antibodies against Treponema pallidum were used for screening syphilis infection, while sexual habits and demographic data information were collected through a semi-structured questionnaire. Data was analyzed comparing groups with/without syphilis. Poisson regression models were used to estimate the reasons of prevalence (RP). RESULTS: The overall prevalence of syphilis was 14.1% (95% CI = 9.8-17.8). FSWs had between 15 and 56 years of age, most were unmarried (65.7%), had attended less than 8 years of formal education (64.1%), had between 10 and 20 partners per week (64.1%), and reported no previous history of STIs (76.1%) and regular use of condom (52.7%). Low level of education attending up to the primary school (RP adjusted = 3.8; 95% CI = 1.4-9.2) and high frequency of anal sex during the past year (RP adjusted = 9.3; 95% CI = 3.5-28.7) were associated with a higher prevalence of syphilis. CONCLUSIONS: A high prevalence of syphilis among FSWs in the Brazilian Amazon region was identified, showing that syphilis is more likely to be transmitted in FSW working in low-income areas, which is attributed to the low level of education. Anal intercourse was found as a risk factor associated with syphilis. Health programs focused on risk populations appear as a rational way to control syphilis spread, which is a rising problem in Brazil and in other several countries.


Asunto(s)
Trabajadores Sexuales/estadística & datos numéricos , Sífilis/epidemiología , Adolescente , Adulto , Brasil/epidemiología , Ciudades/estadística & datos numéricos , Condones/estadística & datos numéricos , Estudios Transversales , Escolaridad , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Conducta Sexual/estadística & datos numéricos , Parejas Sexuales , Sífilis/diagnóstico , Serodiagnóstico de la Sífilis , Treponema pallidum/inmunología , Adulto Joven
18.
Biopreserv Biobank ; 16(5): 350-360, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30325669

RESUMEN

Brazil is one of the most biodiverse countries on Earth, holding ∼10% of the world's vascular plant species. Despite that, Brazilian agriculture is highly dependent on genetic resources originating from other countries. Embrapa (Brazilian Agricultural Research Corporation) is the governmental institution that, since 1973, has been responsible for the introduction and conservation of genetic resources in Brazil. In this article, we report on the experiences that Embrapa has faced over the past 45 years to build and improve a national network for the preservation of plant genetic resources under the coordination of Embrapa Genetic Resources & Biotechnology (CENARGEN), one of the 42 Embrapa decentralized units. The first network-based model, RENARGEN, initiated in 2003, was followed by the National Platform for Genetic Resources (Platform RG) in 2009; and from 2014 until today Embrapa manages the conservation of genetic resources through Portfolio REGEN, in which the plant component is called Plant Genetic Resources Network (RGV). This network covers activities of enrichment, conservation, characterization, and documentation of genebanks. Embrapa's plant genetic resources are conserved in active genebanks (AGs), in long-term seed bank (Colbase), and in vitro and DNA banks. In situ and on-farm conservation are also handled at Embrapa to complement and reinforce ex situ conservation. The latest survey reveals that Embrapa has 134 AGs with ∼150,000 accessions of 1130 plant species, 123,000 accessions of 735 species within Colbase, 1250 in vitro accessions, and 12,000 DNA samples. At least 65% of this collection is documented and available to the public in the Embrapa Alelo system, which also handles quarantine, germplasm exchange, and herbarium data. By the end of 2018, the public Alelo data will be automatically migrated to the Genesys system. In the last 40 years, ∼650,000 accessions have been exchanged by Embrapa, with 70% of them imported from other countries.


Asunto(s)
Plantas/genética , Banco de Semillas/organización & administración , Brasil , Conservación de los Recursos Naturales , Bases de Datos Genéticas , Desarrollo de la Planta , Semillas/genética
19.
Front Microbiol ; 9: 795, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29867783

RESUMEN

HTLV-1 infections are persistent and frequently latent; however, productive infections trigger different types of immunological responses that utilize cytokines to control infection. The present study investigated the role of IFNG +874A/T polymorphisms among 153 HTLV-1-infected individuals (33 clinically diagnosed with TSP/HAM, 22 with rheumatologic manifestations, 2 with dermatitis, 1 with uveitis, and 95 asymptomatic patients) and 300 healthy control individuals. Genotyping and proviral HTLV-1 load assessment were performed using real-time PCR assays, and the plasma levels of IFN-γ were measured using an enzyme immunoassay (ELISA). Genotype frequencies were not significantly different, but the presence of the T allele was higher (p < 0.0142) among the asymptomatic patients. Plasma levels of IFN-γ were significantly higher (p < 0.0137) among those with the TT genotype. Their proviral load was also higher, although this elevation did not reach statistical significance. There was no difference in the IFN-γ plasma levels among the symptomatic patients, even when ranked according to disease severity (TSP/HAM or rheumatologic manifestations). However, the difference among asymptomatic patients with the T allele was significantly higher (p < 0.0016) and similar to the plasma levels observed among symptomatic individuals. These results suggest that the IFNG +874A/T polymorphism may modulate the plasma levels of IFN-γ during HTLV-1 infection. Asymptomatic carriers of the polymorphic genotypes appear to develop an inflammatory response in a shorter timeframe, triggering progression to HTLV-1-related symptoms and disorders. These results further suggest that HTLV-1-infected asymptomatic individuals expressing the IFNG +874A/T polymorphism should be monitored more closely in order to readily detect the increase in clinical symptoms, as these patients are potentially at risk of a poor prognosis and should therefore start available treatment procedures earlier.

20.
Planta Med ; 84(17): 1300-1310, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29929208

RESUMEN

Plants of the genus Phyllanthus, principally Phyllanthus amarus, Phyllanthus urinaria, Phyllanthus niruri, and Phyllanthus tenellus, are used in Brazilian folk medicine to treat kidney stones as well as other ailments, where the latter two species are listed in the Brazilian Pharmacopeia as quebra-pedra (stone-breaker). However, only P. niruri has been shown to be effective in a clinical setting. Nuclear ribosomal internal transcribed spacer (ITS1 - 5.8S rRNA-ITS2), internal transcribed spacer 2, and chloroplasts rbcL, matK, psbA-trnH, trnL, and trnL-trnF were screened for their potential as DNA barcodes for the identification of 48 Phyllanthus taxa in Brazilian medicinal plant germplasm banks and in "living pharmacies". The markers were also tested for their ability to validate four commercial herbal teas labelled as quebra-pedra. Using the criterion of high clade posterior probability in Bayesian phylogenetic analysis, the internal transcribed spacer, internal transcribed spacer 2, and chloroplast matK, psbA-trnH, trnL, and trnL-trnF markers all reliably differentiated the four Phyllanthus species, with the internal transcribed spacer and matK possessing the additional advantage that the genus is well represented for these markers in the Genbank database. However, in the case of rbcL, posterior probability for some clades was low and while P. amarus and P. tenellus formed monophyletic groups, P. niruri and P. urinaria accessions could not be reliably distinguished with this marker. Packaged dried quebra-pedra herb from three Brazilian commercial suppliers comprised P. tenellus, but one sample was also found to be mixed with alfalfa (Medicago sativa). An herb marketed as quebra-pedra from a fourth supplier was found to be composed of a mixture of Desmodium barbatum and P. niruri.


Asunto(s)
Código de Barras del ADN Taxonómico , Phyllanthus/genética , Brasil , Código de Barras del ADN Taxonómico/métodos , ADN de Plantas/genética , Plantas Medicinales/genética , Reacción en Cadena de la Polimerasa
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