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991.
Marcos Fernando Basso Karoline Estefani Duarte Thais Ribeiro Santiago Wagner Rodrigo de Souza Bruno de Oliveira Garcia Brbara Dias Brito da Cunha Adilson Kenji Kobayashi Hugo Bruno Correa Molinari 《Plant Biotechnology》2021,38(2):227
The CRISPR/Cas9 system has been used for genome editing in several organisms, including higher plants. This system induces site-specific mutations in the genome based on the nucleotide sequence of engineered guide RNAs. The complex genomes of C4 grasses makes genome editing a challenge in key grass crops like maize (Zea mays), sorghum (Sorghum bicolor), Brachiaria spp., switchgrass (Panicum virgatum), and sugarcane (Saccharum spp.). Setaria viridis is a diploid C4 grass widely used as a model for these C4 crop plants. Here, an optimized CRISPR/Cas9 binary vector that exploits the non-homologous end joining (NHEJ) system was used to knockout a green fluorescent protein (gfp) transgene in S. viridis accession A10.1. Transformation of embryogenic callus by A. tumefaciens generated ten glufosinate-ammonium resistant transgenic events. In the T0 generation, 60% of the events were biallelic mutants in the gfp transgene with no detectable accumulation of GFP protein and without insertions or deletions in predicted off-target sites. The gfp mutations generated by CRISPR/Cas9 were stable and displayed Mendelian segregation in the T1 generation. Altogether, the system described here is a highly efficient genome editing system for S. viridis, an important model plant for functional genomics studies in C4 grasses. Also, this system is a potential tool for improvement of agronomic traits in C4 crop plants with complex genomes. 相似文献
992.
Farhad Pishgar Mahsima Shabani Thiago Quinaglia A. C. Silva David A. Bluemke Matthew Budoff R Graham Barr Matthew A. Allison Alain G. Bertoni Wendy S. Post Joo A. C. Lima Shadpour Demehri 《PLoS medicine》2021,18(7)
BackgroundGiven the central role of skeletal muscles in glucose homeostasis, deposition of adipose depots beneath the fascia of muscles (versus subcutaneous adipose tissue [SAT]) may precede insulin resistance and type 2 diabetes (T2D) incidence. This study was aimed to investigate the associations between computed tomography (CT)–derived biomarkers for adipose tissue and T2D incidence in normoglycemic adults.Methods and findingsThis study was a population-based multiethnic retrospective cohort of 1,744 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) with normoglycemia (baseline fasting plasma glucose [FPG] less than 100 mg/dL) from 6 United States of America communities. Participants were followed from April 2010 and January 2012 to December 2017, for a median of 7 years. The intermuscular adipose tissue (IMAT) and SAT areas were measured in baseline chest CT exams and were corrected by height squared (SAT and IMAT indices) using a predefined measurement protocol. T2D incidence, as the main outcome, was based on follow-up FPG, review of hospital records, or self-reported physician diagnoses.Participants’ mean age was 69 ± 9 years at baseline, and 977 (56.0%) were women. Over a median of 7 years, 103 (5.9%) participants were diagnosed with T2D, and 147 (8.4%) participants died. The IMAT index (hazard ratio [HR]: 1.27 [95% confidence interval [CI]: 1.15–1.41] per 1-standard deviation [SD] increment) and the SAT index (HR: 1.43 [95% CI: 1.16–1.77] per 1-SD increment) at baseline were associated with T2D incidence over the follow-up. The associations of the IMAT and SAT indices with T2D incidence were attenuated after adjustment for body mass index (BMI) and waist circumference, with HRs of 1.23 (95% CI: 1.09–1.38) and 1.29 (95% CI: 0.96–1.74) per 1-SD increment, respectively. The limitations of this study include unmeasured residual confounders and one-time measurement of adipose tissue biomarkers.ConclusionsIn this study, we observed an association between IMAT at baseline and T2D incidence over the follow-up. This study suggests the potential role of intermuscular adipose depots in the pathophysiology of T2D.Trial registrationClinicalTrials.gov In a cohort study, Shadpour Demehri and colleagues investigate the association between adipose tissue biomarkers and type 2 diabetes incidence in normoglycemic participants in US. NCT00005487相似文献
993.
Aline Garcia Kozlowski Megmar Aparecida dos Santos Carneiro Márcia Alves Dias de Matos Sheila Araújo Teles Jo?o Alves Araújo Filho Koko Otsuki Ana Carolina Paulo Vicente Regina Maria Bringel Martins 《Memórias do Instituto Oswaldo Cruz》2014,109(1):118-121
Human T-cell lymphotropic virus (HTLV) may impact the clinical course of tuberculosis
(TB). Both infections are highly endemic in Brazil. The aim of this study was to
assess the prevalence of HTLV-1/2 in TB patients in Central-West Brazil and to
perform a genetic characterisation of the respective isolates. Of the 402 patients,
six (1.49%) were positive for anti-HTLV and five (1.24%; 95% confidence interval:
0.46-3.05) were infected with HTLV-1/2. Genetic characterisation demonstrated that
the four HTLV-1 isolates belonged to the Transcontinental subgroup A of the
Cosmopolitan subtype a and that the HTLV-2 isolate belonged to subtype a (HTLV-2a/c).
The prevalence of HTLV infection observed in this study is higher than that observed
in local blood donors and the HTLV-1 and 2 subtypes identified are consistent with
those circulating in Brazil. 相似文献
994.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
995.
Yan Zhang Jiang Pan Zheng-Jiao Luan Guo-Chao Xu Sunghoon Park Jian-He Xu 《Applied and environmental microbiology》2014,80(23):7348-7355
A novel nonheme chloroperoxidase (RhEst1), with promiscuous esterase activity for enantioselective hydrolysis of ethyl (S)-2,2-dimethylcyclopropanecarboxylate, was identified from a shotgun library of Rhodococcus sp. strain ECU1013. RhEst1 was overexpressed in Escherichia coli BL21(DE3), purified to homogeneity, and functionally characterized. Fingerprinting analysis revealed that RhEst1 prefers para-nitrophenyl (pNP) esters of short-chain acyl groups. pNP esters with a cyclic acyl moiety, especially that with a cyclobutanyl group, were also substrates for RhEst1. The Km values for methyl 2,2-dimethylcyclopropanecarboxylate (DmCpCm) and ethyl 2,2-dimethylcyclopropane carboxylate (DmCpCe) were 0.25 and 0.43 mM, respectively. RhEst1 could serve as an efficient hydrolase for the bioproduction of optically pure (S)-2,2-dimethyl cyclopropane carboxylic acid (DmCpCa), which is an important chiral building block for cilastatin. As much as 0.5 M DmCpCe was enantioselectively hydrolyzed into (S)-DmCpCa, with a molar yield of 47.8% and an enantiomeric excess (ee) of 97.5%, indicating an extremely high enantioselectivity (E = 240) of this novel and unique biocatalyst for green manufacturing of highly valuable chiral chemicals. 相似文献
996.
Lima JG de Freitas Vinhas C Gomes IN Azevedo CM dos Santos RR Vannier-Santos MA Veras PS 《Biochemical and biophysical research communications》2011,405(4):4686-609
Recent studies have demonstrated that communication takes place between the autophagic and phagocytic pathways, indicating that the convergence of these two pathways plays an important role in the innate immune response against intracellular microbes. The present study investigated the effect of autophagic induction on the phagocytic capacity of murine macrophages. Autophagy induced by physiological and pharmacological means was shown to reduce the phagocytic capacity of murine macrophages, regardless of cell origin or the nature of the phagocytosed particles themselves. This autophagic inhibitory effect on phagocytosis was shown to be an early and reversible event that results in no loss of cell viability. Furthermore, the data presented herein demonstrate that the induction of autophagy does not affect a macrophage’s capacity to recognize and bind to particles, indicating that autophagy does not inhibit the particle recognition process, even though particle internalization is suppressed. The findings herein support the notion that phagocytosis and autophagy may be interdependent and complementary processes. 相似文献
997.
Zaparoli G Barsottini MR de Oliveira JF Dyszy F Teixeira PJ Barau JG Garcia O Costa-Filho AJ Ambrosio AL Pereira GA Dias SM 《Biochemistry》2011,50(45):9901-9910
The necrosis- and ethylene-inducing peptide 1 (NEP1)-like proteins (NLPs) are proteins secreted from bacteria, fungi and oomycetes, triggering immune responses and cell death in dicotyledonous plants. Genomic-scale studies of Moniliophthora perniciosa, the fungus that causes the Witches' Broom disease in cacao, which is a serious economic concern for South and Central American crops, have identified five members of this family (termed MpNEP1-5). Here, we show by RNA-seq that MpNEP2 is virtually the only NLP expressed during the fungus infection. The quantitative real-time polymerase chain reaction results revealed that MpNEP2 has an expression pattern that positively correlates with the necrotic symptoms, with MpNEP2 reaching its highest level of expression at the advanced necrotic stage. To improve our understanding of MpNEP2's molecular mechanism of action, we determined the crystallographic structure of MpNEP2 at 1.8 ? resolution, unveiling some key structural features. The implications of a cation coordination found in the crystal structure were explored, and we show that MpNEP2, in contrast to another previously described member of the NLP family, NLP(Pya) from Pythium aphanidermatum, does not depend on an ion to accomplish its necrosis- and electrolyte leakage-promoting activities. Results of site-directed mutagenesis experiments confirmed the importance of a negatively charged cavity and an unforeseen hydrophobic β-hairpin loop for MpNEP2 activity, thus offering a platform for compound design with implications for disease control. Electron paramagnetic resonance and fluorescence assays with MpNEP2 performed in the presence of lipid vesicles of different compositions showed no sign of interaction between the protein and the lipids, implying that MpNEP2 likely requires other anchoring elements from the membrane to promote cytolysis or send death signals. 相似文献
998.
Thompson CC Marin MA Dias GM Dutilh BE Edwards RA Iida T Thompson FL Vicente AC 《Journal of bacteriology》2011,193(20):5877-5878
Vibrio cholerae O1 Amazonia is a pathogen that was isolated from cholera-like diarrhea cases in at least two countries, Brazil and Ghana. Based on multilocus sequence analysis, this lineage belongs to a distinct profile compared to strains from El Tor and classical biotypes. The genomic analysis revealed that it contains Vibrio pathogenicity island 2 and a set of genes related to pathogenesis and fitness, such as the type VI secretion system, present in choleragenic V. cholerae strains. 相似文献
999.
The influence of social factors on the modulation of male testosterone levels has been demonstrated among several vertebrate species. In addition to sexual activity, parental care and reproductive competition affect testosterone secretion. We examined variations in testosterone levels among male black howlers (Alouatta pigra) in various social contexts. Fecal samples were collected from nine males living in five different groups in the Mexican state of Campeche. The potential for intragroup and extragroup competition varied among the groups. The number of resident males living in the groups was the only variable that significantly explained variations in testosterone levels. Males living in unimale groups had higher testosterone levels; the highest testosterone levels were recorded for males that had experienced a shift from multimale to unimale group compositions. In this species, the probability of being challenged by extragroup males and evicted from the group during immigration events increases when males live in unimale groups. Therefore, our results suggest that male black howlers respond to competition for group membership by increasing their testosterone levels. In this context, testosterone secretion represents an anticipatory response to reproductive conflicts. Therefore, although males living in unimale groups have exclusive access to females, they face higher physiological costs associated with sustaining high testosterone levels for extended time periods. 相似文献
1000.
Lanzarotti E Pellizza L Bercovich A Foti M Coria SH Vazquez SC Ruberto L Hernández EA Dias RL Mac Cormack WP Cicero DO Smal C Nicolas MF Vasconcelos AT Marti MA Turjanski AG 《Journal of bacteriology》2011,193(23):6797-6798
A psychrotolerant marine bacterial strain, designated JUB59(T), was isolated from Antarctic surface seawater and classified as a new species of the genus Bizionia. Here, we present the first draft genome sequence for this genus, which suggests interesting features such as UV resistance, hydrolytic exoenzymes, and nitrogen metabolism. 相似文献