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1.
Forensic Sci Int Genet ; 71: 103055, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38762965

RESUMO

Forensic Investigative Genetic Genealogy, a recent sub discipline of forensic genomics, leverages the high throughput and sensitivity of detection of next generation sequencing and established genetic and genealogical approaches to support the identification of human remains from missing persons investigations and investigative lead generation in violent crimes. To facilitate forensic DNA evidence analysis, the ForenSeq® Kintelligence multiplex, consisting of 10,230 SNPs, was developed. Design of the ForenSeq Kintelligence Kit, the MiSeq FGx® Sequencing System and the ForenSeq Universal Analysis Software is described. Developmental validation in accordance with SWGDAM guidelines and forensic quality assurance standards, using single source samples, is reported for the end-to-end workflow from library preparation to data interpretation. Performance metrics support the conclusion that more genetic information can be obtained from challenging samples compared to other commercially available forensic targeted DNA assays developed for capillary electrophoresis (CE) or other current next generation sequencing (NGS) kits due to the higher number of markers, the overall shorter amplicon sizes (97.8% <150 bp), and kit design. Data indicate that the multiplex is robust and fit for purpose for a wide range of quantity and quality samples. The ForenSeq Kintelligence Kit and the Universal Analysis Software allow transfer of the genetic component of forensic investigative genetic genealogy to the operational forensic laboratory.


Assuntos
Impressões Digitais de DNA , Sequenciamento de Nucleotídeos em Larga Escala , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Software , Humanos
2.
Chemosphere ; 350: 141013, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38145847

RESUMO

Photocatalysis has emerged as a highly effective method for eliminating organic pollutants from wastewater. The immobilization of photocatalysts on a suitable solid surface is highly desired to achieve enhanced photocatalytic activity. In this work, graphitic carbon nitride (g-C3N4) is synthesized with three different precursors (melamine, thiourea, and urea) via a simple thermal exfoliation method and successfully immobilized on a polyurethane (PU) foam using the facile dip coating method. The photocatalytic activity of g-C3N4 bulk and g-C3N4 nanosheets-coated PU foams are compared using methyl orange dye and tetracycline hydrochloride as a test pollutant under visible light irradiation. Our results show that the type of precursors and surface area of the sample have a significant role in photocatalytic dye degradation. The urea-based g-C3N4 - PU foam shows better photocatalytic activity than the melamine or thiourea based g-C3N4 - PU foam. The scavenger test unveils that superoxide radical (O2●-) and holes (h+) are the main reactive oxidative species responsible for MO dye and TcH degradations. The cycling experiments are also carried out to confirm the reusability of the g-C3N4 floating catalyst for practical applications. Furthermore, a possible reaction mechanism has also been proposed.


Assuntos
Poluentes Ambientais , Poliuretanos , Luz , Ureia , Tioureia
4.
Forensic Sci Int Synerg ; 6: 100316, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36879828

RESUMO

In 2022, the National Technology Validation and Implementation Collaborative (NTVIC) was established. Its mission is to collaborate across the US on validation, method development, and implementation. The NTVIC is comprised of 13 federal, state and local government crime laboratory leaders, joined by university researchers, and private technology and research companies. One of the NTVIC's first initiatives was to generate this draft policy document. This document provides guidelines and considerations for crime laboratories and investigative agencies exploring the establishment of a forensic investigative genetic genealogy (FIGG) program. While each jurisdiction is responsible for its own program policy, sharing minimum standards and best practices to optimize resources, promote technology implementation and elevate quality is a goal of the NTVIC.

5.
Virusdisease ; 32(2): 244-250, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34350314

RESUMO

Flow cytometry analysis was carried out to detect the progression of apoptosis in haemocytes of WSSV infected Penaeus vannamei at different time-points (1.5 hpi, 18 hpi and 56 hpi). Apoptosis in haemocytes was found to increase with time of infectivity from 5.06 to 69.63%. Quantitative real-time PCR (qPCR) was used for the expression analysis of four apoptosis-related genes such as Death-associated protein 1, caspase-5, translationally controlled tumor protein, and cathepsin D. The evidence of apoptosis in haemocytes of P. vannamei was established as shown by significant increase in the percentage of late apoptotic cells due to WSSV infection in shrimp. The present study gives an insight to the apoptosis rate in a WSSV infected shrimp during the course of infection and the role of apoptosis related genes.

6.
Niger J Clin Pract ; 23(7): 1026-1029, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620736

RESUMO

When teeth have responded poorly to conventional endodontic treatment or when they cannot be treated adequately by nonsurgical means, surgical endodontics remains the treatment of choice. Healing of apical lesions occurs by repair, most of the time. "Repair is the healing of a wound by tissue that does not fully restore the architecture or function of the affected unit". Since this is not ideal, newer regenerative procedures that aim to restore lost tissue have been introduced. ß -Tricalcium phosphate is an alloplastic bone graft material that forms a scaffold for closing the bony defect. It is osteoconductive. Platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are platelet concentrates, rich in growth factors and they promote regeneration by osteoinduction. This article describes cases of bone augmentation with a combination of PRP + ß -TCP and PRF + ß -TCP for treatment of the chronic periapical lesion. The cases were followed for six months and one year and healing was evaluated quantitatively using cone beam computed tomography.


Assuntos
Fosfatos de Cálcio/uso terapêutico , Tomografia Computadorizada de Feixe Cônico/métodos , Fibrina Rica em Plaquetas , Plasma Rico em Plaquetas , Adulto , Regeneração Óssea , Transplante Ósseo , Feminino , Humanos , Radiografia Dentária , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/cirurgia , Colo do Dente/patologia , Resultado do Tratamento , Cicatrização
7.
Sci Rep ; 9(1): 13509, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31534145

RESUMO

Shrimp aquaculture is severely affected by WSSV. Despite an increasing effort to understand host/virus interaction by characterizing changes in gene expression (GE) following WSSV infection, the majority of published studies have focussed on a single time-point, providing limited insight on the development of host-pathogen interaction over the infection cycle. Using RNA-seq, we contrasted GE in gills of Litopenaeus vannamei at 1.5, 18 and 56 hours-post-infection (hpi), between WSSV-challenged and control shrimps. Time course analysis revealed 5097 differentially expressed genes: 63 DEGs were viral genes and their expression in WSSV group either peaked at 18 hpi (and decreased at 56 hpi) or increased linearly up to 56 hpi, suggesting a different role played by these genes during the course of infection. The remaining DEGs showed that WSSV altered the expression of metabolic, immune, apoptotic and cytoskeletal genes and was able to inhibit NF-κB and JAK/STAT pathways. Interestingly, GE changes were not consistent through the course of infection but were dynamic with time, suggesting the complexity of host-pathogen interaction. These data offer novel insights into the cellular functions that are affected during the course of infection and ultimately provide a valuable resource towards our understanding of the host-pathogen dynamics and its variation with time.


Assuntos
Interações Hospedeiro-Patógeno/genética , Penaeidae/genética , Vírus da Síndrome da Mancha Branca 1/genética , Animais , Aquicultura/métodos , Decápodes/genética , Genes Virais/genética , Brânquias/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/genética , Infecções/genética , Estudos Longitudinais , Penaeidae/virologia , Transcriptoma/genética , Vírus da Síndrome da Mancha Branca 1/patogenicidade
8.
Fish Shellfish Immunol ; 93: 288-295, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330255

RESUMO

In recent years, the importance of viral and host microRNAs (miRNAs) in mediating viral replication and control of host cellular machinery, has been realised and increasing efforts have been taken in order to understand the interactions of miRNAs from host and pathogen during infection. However, all existing studies has thus far been conducted in controlled experimental conditions and the veracity of these data for field conditions are yet to be established. In this framework, small RNA sequencing was performed to identify the miRNAs involved in shrimp (Penaeus vannamei) immune responses under two different WSSV infection conditions of natural infection and experimentally challenged conditions. The expression profiles of miRNAs of shrimp infected with WSSV under two contrasting conditions were compared and as a result, 23365 known miRNAs and 481 novel miRNAs were identified. Amongst the most abundantly expressed miRNAs, the hypoxia related miR-210 and immune pathway related miR-29b were expressed only in infected shrimps of both conditions. miR-8-5p, having a functional role in modulation of chitin biosynthesis was exclusively represented in higher numbers in the WSSV -infected shrimps under natural conditions whilst four of the miRNAs (mja-miR-6493-5p, mja-miR-6492, mmu-miR-3968, tcf-miR-9b-5p) identified from shrimps collected from pond culture targeted chitinase, an important enzyme involved in growth and moulting in shrimps, indicating an interaction between WSSV infection and moult cycle under culture conditions. Some of the miRNAs (tca-miR-87b-3p, cte-miR-277a) and miRNAs belonging to class miR-9, miR-981 that were identified only in WSSV infected shrimps under experimental conditions, are known to respond against WSSV infection in shrimps. Moreover, the miRNA target prediction revealed several immune-related gene targets such as cathepsin, c-type lectin, haemocyanin and ubiquitin protein ligase were commonly identified under both the conditions. However, the miRNAs identified from challenge experiment had wide number of gene targets as compared to the miRNAs of natural infection. The shrimp miRNA mja-miR-6489-3p, was also found to target early virus gene wsv001 of WSSV. Our study, therefore, provides the comparative analysis of miRNA expression from shrimp during WSSV infection in two different conditions.


Assuntos
Imunidade Inata/genética , MicroRNAs/genética , Penaeidae/genética , Penaeidae/imunologia , Transcriptoma/imunologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Interações Hospedeiro-Patógeno , MicroRNAs/imunologia
9.
Mol Biol Rep ; 45(5): 951-960, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30008142

RESUMO

Flow cytometry was used for estimating the genome size of five brackishwater finfish and four shrimp species. The genome size for Lutjanus argentimaculatus was 0.95 ± 0.10 and 0.79 ± 0.01 pg for Scatophagus argus. The genome sizes for Chanos chanos (0.72 ± 0.01 pg), Etroplus suratensis (1.71 ± 0.16 pg) and Liza macrolepis (0.87 ± 0.02 pg) which are important aquaculture species are reported for the first time in this study. The phylogenetic tree constructed using sixty-seven sequence accessions of cytochrome c oxidase subunit 1 (COI) gene of Lates calcarifer revealed two separate clades. The Indian Lates calcarifer species with estimated genome size of 0.44 ± 0.02 pg belonged to a clade different than that of South East Asia and Australia reported to have larger genome size. The genome size for the four major species of genus Penaeus (Penaeus monodon, Penaeus indicus, Penaeus vannamei and Penaeus japonicus) were found in similar range. The genome size of female shrimps ranged from 2.91 ± 0.03 pg (P. monodon) to 2.14 ± 0.02 pg (P. japonicus). In male shrimps, the genome size ranged from 2.86 ± 0.06 pg (P. monodon) to 2.19 ± 0.02 pg (P. indicus). Significant difference was observed in the genome size between male and female shrimp of all species except in P. monodon. The highest relative difference of 12.78% was observed in the genome size between the either sex in P. indicus. The interspecific relative difference of 30.59% in genome size was highest between the male shrimps of P. monodon and P. indicus and 35.98% between the female shrimps of P. monodon and P. japonicus. The stored gills and pleopod tissues could be successfully used up to 3 weeks to estimate the genome size in shrimps.


Assuntos
Peixes/genética , Tamanho do Genoma/genética , Penaeidae/genética , Animais , Aquicultura , Feminino , Citometria de Fluxo/métodos , Genoma/genética , Masculino , Filogenia , Águas Salinas
10.
BMC Plant Biol ; 17(1): 264, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29281982

RESUMO

BACKGROUND: Arabidopsis has 5 paralogs of the S-adenosylmethionine decarboxylase (SAMDC) gene. Neither their specific role in development nor the role of positive/purifying selection in genetic divergence of this gene family is known. While some data are available on organ-specific expression of AtSAMDC1, AtSAMDC2, AtSAMDC3 and AtSAMDC4, not much is known about their promoters including AtSAMDC5, which is believed to be non-functional. RESULTS: (1) Phylogenetic analysis of the five AtSAMDC genes shows similar divergence pattern for promoters and coding sequences (CDSs), whereas, genetic divergence of 5'UTRs and 3'UTRs was independent of the promoters and CDSs; (2) while AtSAMDC1 and AtSAMDC4 promoters exhibit high activity (constitutive in the former), promoter activities of AtSAMDC2, AtSAMDC3 and AtSAMDC5 are moderate to low in seedlings (depending upon translational or transcriptional fusions), and are localized mainly in the vascular tissues and reproductive organs in mature plants; (3) based on promoter activity, it appears that AtSAMDC5 is both transcriptionally and translationally active, but based on it's coding sequence it seems to produce a non-functional protein; (4) though 5'-UTR based regulation of AtSAMDC expression through upstream open reading frames (uORFs) in the 5'UTR is well known, no such uORFs are present in AtSAMDC4 and AtSAMDC5; (5) the promoter regions of all five AtSAMDC genes contain common stress-responsive elements and hormone-responsive elements; (6) at the organ level, the activity of AtSAMDC enzyme does not correlate with the expression of specific AtSAMDC genes or with the contents of spermidine and spermine. CONCLUSIONS: Differential roles of positive/purifying selection were observed in genetic divergence of the AtSAMDC gene family. All tissues express one or more AtSAMDC gene with significant redundancy, and concurrently, there is cell/tissue-specificity of gene expression, particularly in mature organs. This study provides valuable information about AtSAMDC promoters, which could be useful in future manipulation of crop plants for nutritive purposes, stress tolerance or bioenergy needs. The AtSAMDC1 core promoter might serve the need of a strong constitutive promoter, and its high expression in the gametophytic cells could be exploited, where strong male/female gametophyte-specific expression is desired; e.g. in transgenic modification of crop varieties.


Assuntos
Adenosilmetionina Descarboxilase/genética , Arabidopsis/genética , Família Multigênica/genética , Poliaminas/metabolismo , Transcriptoma , Adenosilmetionina Descarboxilase/metabolismo , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Filogenia
11.
J Clin Diagn Res ; 11(7): ZC18-ZC21, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28893035

RESUMO

INTRODUCTION: Chlorhexidine (CHX) is generally used as the final irrigating solution in root canal therapy. Recent studies have reported that, toxic precipitates containing parachloroaniline (PCA) are formed when CHX reacts with sodium hypochlorite (NaOCl). Whereas, Alexidine (ALX), a bisbiguanide disinfectant similar to CHX, has proven to form no precipitates with NaOCl. AIM: To compare antimicrobial activity of different concentrations of ALX with CHX individually and when combined with NaOCl against E. faecalis strains. MATERIALS AND METHODS: Different concentrations of ALX and CHX (0.5%, 1%, and 2%) were tested individually and when mixed with 2.5% NaOCl (1:1 ratio) using disc diffusion method against E. faecalis. After 24 hours incubation at 37°C, zones of inhibition were measured for each solution. The results obtained were statistically analysed using one way ANOVA and Scheffe's post-hoc tests. The p-value <0.001 was considered as highly significant. RESULTS: Regardless of the concentrations, ALX obtained the best results in comparison to CHX. There was no statistically significant difference between ALX + NaOCl and CHX + NaOCl mixtures. CONCLUSION: The present study showed that, the antimicrobial property of ALX against E. faecalis was found to be superior to CHX at same concentrations.

12.
BMC Plant Biol ; 16(1): 113, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27188293

RESUMO

BACKGROUND: With the increasing interest in metabolic engineering of plants using genetic manipulation and gene editing technologies to enhance growth, nutritional value and environmental adaptation, a major concern is the potential of undesirable broad and distant effects of manipulating the target gene or metabolic step in the resulting plant. A comprehensive transcriptomic and metabolomic analysis of the product may shed some useful light in this regard. The present study used these two techniques with plant cell cultures to analyze the effects of genetic manipulation of a single step in the biosynthesis of polyamines because of their well-known roles in plant growth, development and stress responses. RESULTS: The transcriptomes and metabolomes of a control and a high putrescine (HP) producing cell line of poplar (Populus nigra x maximowiczii) were compared using microarrays and GC/MS. The HP cells expressed an ornithine decarboxylase transgene and accumulated several-fold higher concentrations of putrescine, with only small changes in spermidine and spermine. The results show that up-regulation of a single step in the polyamine biosynthetic pathway (i.e. ornithine → putrescine) altered the expression of a broad spectrum of genes; many of which were involved in transcription, translation, membrane transport, osmoregulation, shock/stress/wounding, and cell wall metabolism. More than half of the 200 detected metabolites were significantly altered (p ≤ 0.05) in the HP cells irrespective of sampling date. The most noteworthy differences were in organic acids, carbohydrates and nitrogen-containing metabolites. CONCLUSIONS: The results provide valuable information about the role of polyamines in regulating nitrogen and carbon use pathways in cell cultures of high putrescine producing transgenic cells of poplar vs. their low putrescine counterparts. The results underscore the complexity of cellular responses to genetic perturbation of a single metabolic step related to nitrogen metabolism in plants. Combined with recent studies from our lab, where we showed that higher putrescine production caused an increased flux of glutamate into ornithine concurrent with enhancement in glutamate production via additional nitrogen and carbon assimilation, the results from this study provide guidance in designing transgenic plants with increased nitrogen use efficiency, especially in plants intended for non-food/feed applications (e.g. increased biomass production for biofuels).


Assuntos
Metaboloma/genética , Putrescina/biossíntese , Transcriptoma/genética , Cromatografia Gasosa-Espectrometria de Massas , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Poliaminas/metabolismo , Populus/genética , Populus/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
13.
Front Plant Sci ; 7: 78, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26909083

RESUMO

The metabolism of glutamate into ornithine, arginine, proline, and polyamines is a major network of nitrogen-metabolizing pathways in plants, which also produces intermediates like nitric oxide, and γ-aminobutyric acid (GABA) that play critical roles in plant development and stress. While the accumulations of intermediates and the products of this network depend primarily on nitrogen assimilation, the overall regulation of the interacting sub-pathways is not well understood. We tested the hypothesis that diversion of ornithine into polyamine biosynthesis (by transgenic approach) not only plays a role in regulating its own biosynthesis from glutamate but also affects arginine and proline biosynthesis. Using two high putrescine producing lines of Arabidopsis thaliana (containing a transgenic mouse ornithine decarboxylase gene), we studied the: (1) effects of exogenous supply of carbon and nitrogen on polyamines and pools of soluble amino acids; and, (2) expression of genes encoding key enzymes in the interactive pathways of arginine, proline and GABA biosynthesis as well as the catabolism of polyamines. Our findings suggest that: (1) the overall conversion of glutamate to arginine and polyamines is enhanced by increased utilization of ornithine for polyamine biosynthesis by the transgene product; (2) proline and arginine biosynthesis are regulated independently of polyamines and GABA biosynthesis; (3) the expression of most genes (28 that were studied) that encode enzymes of the interacting sub-pathways of arginine and GABA biosynthesis does not change even though overall biosynthesis of Orn from glutamate is increased several fold; and (4) increased polyamine biosynthesis results in increased assimilation of both nitrogen and carbon by the cells.

14.
Tree Physiol ; 35(8): 894-909, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26116927

RESUMO

We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements were analyzed for control, low N (LN, 50 kg NH4NO3 ha(-1) year(-1)) and high N (HN, 150 kg NH4NO3 ha(-1) year(-1)) treatments. In the pine stands, partitioning of excess N into foliar PAs and AAs increased with both N treatments until 2002. By 2005, several of these effects on N metabolites disappeared for HN, and by 2008 they were mostly observed for LN plot. A significant decline in foliar Ca and P was observed mostly with HN for a few years until 2005. However, sapwood data actually showed an increase in Ca, Mg and Mn and no change in PAs in the HN plot for 2008, while AAs data revealed trends that were generally similar to foliage for 2008. Concomitant with these changes, mortality data revealed a large number of dead trees in HN pine plots by 2002; the mortality rate started to decline by 2005. Oak trees in the hardwood plot did not exhibit any major changes in PAs, AAs, nutrients and mortality rate with LN treatment, indicating that oak trees were able to tolerate the yearly doses of 50 kg NH4NO3 ha(-1) year(-1). However, HN trees suffered from physiological and nutritional stress along with increased mortality in 2008. In this case also, foliar data were supported by the sapwood data. Overall, both low and high N applications resulted in greater physiological stress to the pine trees than the oaks. In general, the time course of changes in metabolic data are in agreement with the published reports on changes in soil chemistry and microbial community structure, rates of soil carbon sequestration and production of woody biomass for this chronic N study. This correspondence of selected metabolites with other measures of forest functions suggests that the metabolite analyses are useful for long-term monitoring of the health of forest trees.


Assuntos
Nitrogênio/metabolismo , Pinus/metabolismo , Quercus/metabolismo , Biomassa , Carbono/metabolismo , Florestas , Massachusetts , Solo
15.
Tree Physiol ; 35(5): 574-80, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25934989

RESUMO

The main goal of this study was to develop a method for the extraction and indirect estimation of the quantity of calcium oxalate (CaOx) in the foliage of trees. Foliar tissue was collected from a single tree of each species (five conifers and five hardwoods) for comparison of extractions in different solvents using 10 replicates per species from the same pool of tissue. For each species, calcium (Ca) and oxalate were extracted sequentially in double deionized water and 2N acetic acid, and finally, five replicate samples were extracted in 5% (0.83N) perchloric acid (PCA) and the other five in 2N hydrochloric acid (HCl); three cycles of freezing and thawing were used for each solvent. Total ions were extracted by microwave digestion. Calcium was quantified with an inductively coupled plasma emission spectrophotometer method and oxalate was eluted and quantified using a high performance liquid chromatography method. This experiment was repeated again with two conifer and two hardwood species using four trees per species, and two analytical replicates for each tree. We report here that, regardless of age of individual trees within a species, time of collection or species type, the third extraction in PCA or HCl resulted in near equimolar quantities of Ca and oxalate (r(2) ≥ 0.99). This method provides an easy estimate of the quantity of CaOx crystals using a small sample of foliar tissue. An additional benefit of PCA is that it precipitates the nucleic acids and proteins, allowing the quantification of several free/soluble metabolites such as amino acids, polyamines, organic acids and inorganic elements all from a single sample extract.


Assuntos
Botânica/métodos , Oxalato de Cálcio/análise , Árvores/química , Oxalato de Cálcio/isolamento & purificação , Oxalato de Cálcio/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Árvores/metabolismo
16.
Front Microbiol ; 6: 49, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25762982

RESUMO

The impact of chronic nitrogen amendments on bacterial communities was evaluated at Harvard Forest, Petersham, MA, USA. Thirty soil samples (3 treatments × 2 soil horizons × 5 subplots) were collected in 2009 from untreated (control), low nitrogen-amended (LN; 50 kg NH4NO3 ha(-1) yr(-1)) and high nitrogen-amended (HN; 150 kg NH4NO3 ha(-1) yr(-1)) plots. PCR-amplified partial 16S rRNA gene sequences made from soil DNA were subjected to pyrosequencing (Turlapati et al., 2013) and analyses using oligotyping. The parameters M (the minimum count of the most abundant unique sequence in an oligotype) and s (the minimum number of samples in which an oligotype is expected to be present) had to be optimized for forest soils because of high diversity and the presence of rare organisms. Comparative analyses of the pyrosequencing data by oligotyping and operational taxonomic unit clustering tools indicated that the former yields more refined units of taxonomy with sequence similarity of ≥99.5%. Sequences affiliated with four new phyla and 73 genera were identified in the present study as compared to 27 genera reported earlier from the same data (Turlapati et al., 2013). Significant rearrangements in the bacterial community structure were observed with N-amendments revealing the presence of additional genera in N-amended plots with the absence of some that were present in the control plots. Permutational MANOVA analyses indicated significant variation associated with soil horizon and N treatment for a majority of the phyla. In most cases soil horizon partitioned more variation relative to treatment and treatment effects were more evident for the organic (Org) horizon. Mantel test results for Org soil showed significant positive correlations between bacterial communities and most soil parameters including NH4 and NO3. In mineral soil, correlations were seen only with pH, NH4, and NO3. Regardless of the pipeline used, a major hindrance for such a study remains to be the lack of reference databases for forest soils.

17.
Bioinformatics ; 29(16): 2041-3, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23736529

RESUMO

SUMMARY: An ultrafast DNA sequence aligner (Isaac Genome Alignment Software) that takes advantage of high-memory hardware (>48 GB) and variant caller (Isaac Variant Caller) have been developed. We demonstrate that our combined pipeline (Isaac) is four to five times faster than BWA + GATK on equivalent hardware, with comparable accuracy as measured by trio conflict rates and sensitivity. We further show that Isaac is effective in the detection of disease-causing variants and can easily/economically be run on commodity hardware. AVAILABILITY: Isaac has an open source license and can be obtained at https://github.com/sequencing.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Alinhamento de Sequência/métodos , Análise de Sequência de DNA/métodos , Software , Variação Genética , Genoma Humano , Humanos
18.
FEMS Microbiol Ecol ; 83(2): 478-93, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22974374

RESUMO

At the Harvard Forest, Petersham, MA, the impact of 20 years of annual ammonium nitrate application to the mixed hardwood stand on soil bacterial communities was studied using 16S rRNA genes pyrosequencing. Amplification of 16S rRNA genes was done using DNA extracted from 30 soil samples (three treatments × two horizons × five subplots) collected from untreated (control), low N-amended (50 kg ha(-1) year(-1)) and high N-amended (150 kg ha(-1) year(-1)) plots. A total of 1.3 million sequences were processed using qiime. Although Acidobacteria represented the most abundant phylum based on the number of sequences, Proteobacteria were the most diverse in terms of operational taxonomic units (OTUs). UniFrac analyses revealed that the bacterial communities differed significantly among soil horizons and treatments. Microsite variability among the five subplots was also evident. Nonmetric multidimensional scaling ordination of normalized OTU data followed by permutational manova further confirmed these observations. Richness indicators and indicator species analyses revealed higher bacterial diversity associated with N amendment. Differences in bacterial diversity and community composition associated with the N treatments were also observed at lower phylogenetic levels. Only 28-35% of the 6 936 total OTUs identified were common to three treatments, while the rest were specific to one treatment or common to two.


Assuntos
Bactérias/classificação , Fertilizantes , Nitratos/farmacologia , Microbiologia do Solo , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , DNA Bacteriano/química , Genes de RNAr , Massachusetts , Filogenia , RNA Ribossômico 16S/genética , Solo/química , Árvores/microbiologia
20.
Infect Genet Evol ; 12(6): 1312-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22484107

RESUMO

Cell-mediated immunity is critical for the control of Mycobacterium tuberculosis infection. We hypothesized that those proteins of M. tuberculosis (MTB) that do not have homologs in humans as well as human gut flora, would mount a good antigenic response in man, and employed a bioinformatics approach to identify MTB antigens capable of inducing a robust cell-mediated immune response in humans. In the first step we identified 624 MTB proteins that had no homologs in humans. Comparison of this set of proteins with the proteome of 77 different microbes that comprise the human gut flora narrowed down the list to 180 proteins unique to MTB. Twenty nine of the 180 proteins are known to be associated with dormancy. Since dormancy associated proteins are known to harbor CTL epitopes, we selected four representative unique proteins and subjected them to epitope analysis using ProPred1. Nineteen novel promiscuous epitopes were identified in the four proteins. Population coverage for 7 of the 19 shortlisted epitopes including Rv3852 (58-KPAEAPVSL, 112-VPLIVAVTL, 118-VTLSLLALL and 123-LALLLIRQL), Rv2706c (66-RPLSGVSFL) Rv3466 (8- RIVEVFDAL and 38-RSLERLECL) was >74%. These novel promiscuous epitopes are conserved in other virulent MTB strains, and can therefore be further investigated for their immunological relevance and usefulness as vaccine candidates.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Epitopos de Linfócito T/análise , Mycobacterium tuberculosis/imunologia , Antígenos de Bactérias/química , Proteínas de Bactérias/química , Biologia Computacional/métodos , Simulação por Computador , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Mycobacterium tuberculosis/química , Linfócitos T Citotóxicos/imunologia , Vacinas contra a Tuberculose/imunologia
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