24 results on '"González RH"'
Search Results
2. Idiopathic intracranial hypertension in patients with spontaneous cerebrospinal fluid leak.
- Author
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Pacheco EC, González RH, Hidalgo LOV, Olhovich IG, Villegas TG, Castañeda CR, and Garcia JM
- Abstract
The cerebrospinal fluid rhinorrhoea is rare like a cause of a nasal discharge; it indicates a communication between the noise and the subarachnoid space, it is more commonly traumatic and it is the result of the rupture of the arachnoid and dura mater, elevation of the pressure of cerebrospinal fluid or an osseous defect. The spontaneous cerebrospinal fluid rhinorrhoea, occurs in 3 to 4% of the cases; in 55% the pressure of the cerebrospinal is normal and it is elevated in 45%. The osseous architecture of the base of the skull has a great importance in the development of fistulas of CSF. The osseous defects are due to the slimming and weakness of the natural barrier; it could be considered like a congenital anormaly. The cribriform area is recognized like the potentially weakest. The mechanism that precipitates the apparition of fistulas de CSF isn't clear. Objective: demonstrate that the intracranial hypertension idiopathic is a etiologic factor of the development of the spontaneous nasal CSF leak. Material and methods: there were studied 8 patients with the diagnostic of de fistula of CSF in the Neurosurgery and Neurology National Institute, realizing the lumbar puncture for the measurement of the intracranial pressure. Results: the studies reported that the 28.57% of the patients presented IIH. [ABSTRACT FROM AUTHOR]
- Published
- 2009
3. Harnessing landrace diversity empowers wheat breeding.
- Author
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Cheng S, Feng C, Wingen LU, Cheng H, Riche AB, Jiang M, Leverington-Waite M, Huang Z, Collier S, Orford S, Wang X, Awal R, Barker G, O'Hara T, Lister C, Siluveru A, Quiroz-Chávez J, Ramírez-González RH, Bryant R, Berry S, Bansal U, Bariana HS, Bennett MJ, Bicego B, Bilham L, Brown JKM, Burridge A, Burt C, Buurman M, Castle M, Chartrain L, Chen B, Denbel W, Elkot AF, Fenwick P, Feuerhelm D, Foulkes J, Gaju O, Gauley A, Gaurav K, Hafeez AN, Han R, Horler R, Hou J, Iqbal MS, Kerton M, Kondic-Spica A, Kowalski A, Lage J, Li X, Liu H, Liu S, Lovegrove A, Ma L, Mumford C, Parmar S, Philp C, Playford D, Przewieslik-Allen AM, Sarfraz Z, Schafer D, Shewry PR, Shi Y, Slafer GA, Song B, Song B, Steele D, Steuernagel B, Tailby P, Tyrrell S, Waheed A, Wamalwa MN, Wang X, Wei Y, Winfield M, Wu S, Wu Y, Wulff BBH, Xian W, Xu Y, Xu Y, Yuan Q, Zhang X, Edwards KJ, Dixon L, Nicholson P, Chayut N, Hawkesford MJ, Uauy C, Sanders D, Huang S, and Griffiths S
- Subjects
- Alleles, Genetic Introgression, Genome, Plant genetics, Haplotypes genetics, Linkage Disequilibrium genetics, Quantitative Trait Loci genetics, Whole Genome Sequencing, Phylogeny, Genetic Association Studies, Food Security, Crops, Agricultural genetics, Genetic Variation genetics, Phenotype, Plant Breeding methods, Triticum classification, Triticum genetics, Biodiversity
- Abstract
Harnessing genetic diversity in major staple crops through the development of new breeding capabilities is essential to ensure food security
1 . Here we examined the genetic and phenotypic diversity of the A. E. Watkins landrace collection2 of bread wheat (Triticum aestivum), a major global cereal, by whole-genome re-sequencing of 827 Watkins landraces and 208 modern cultivars and in-depth field evaluation spanning a decade. We found that modern cultivars are derived from two of the seven ancestral groups of wheat and maintain very long-range haplotype integrity. The remaining five groups represent untapped genetic sources, providing access to landrace-specific alleles and haplotypes for breeding. Linkage disequilibrium-based haplotypes and association genetics analyses link Watkins genomes to the thousands of identified high-resolution quantitative trait loci and significant marker-trait associations. Using these structured germplasm, genotyping and informatics resources, we revealed many Watkins-unique beneficial haplotypes that can confer superior traits in modern wheat. Furthermore, we assessed the phenotypic effects of 44,338 Watkins-unique haplotypes, introgressed from 143 prioritized quantitative trait loci in the context of modern cultivars, bridging the gap between landrace diversity and current breeding. This study establishes a framework for systematically utilizing genetic diversity in crop improvement to achieve sustainable food security., (© 2024. The Author(s).)- Published
- 2024
- Full Text
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4. Rust expression browser: an open source database for simultaneous analysis of host and pathogen gene expression profiles with expVIP.
- Author
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Adams TM, Olsson TSG, Ramírez-González RH, Bryant R, Bryson R, Campos PE, Fenwick P, Feuerhelm D, Hayes C, Henriksson T, Hubbard A, Jevtić R, Judge C, Kerton M, Lage J, Lewis CM, Lilly C, Meidan U, Novoselović D, Patrick C, Wanyera R, and Saunders DGO
- Subjects
- Plant Diseases genetics, Triticum genetics, Virulence, Basidiomycota genetics, Transcriptome
- Abstract
Background: Transcriptomics is being increasingly applied to generate new insight into the interactions between plants and their pathogens. For the wheat yellow (stripe) rust pathogen (Puccinia striiformis f. sp. tritici, Pst) RNA-based sequencing (RNA-Seq) has proved particularly valuable, overcoming the barriers associated with its obligate biotrophic nature. This includes the application of RNA-Seq approaches to study Pst and wheat gene expression dynamics over time and the Pst population composition through the use of a novel RNA-Seq based surveillance approach called "field pathogenomics". As a dual RNA-Seq approach, the field pathogenomics technique also provides gene expression data from the host, giving new insight into host responses. However, this has created a wealth of data for interrogation., Results: Here, we used the field pathogenomics approach to generate 538 new RNA-Seq datasets from Pst-infected field wheat samples, doubling the amount of transcriptomics data available for this important pathosystem. We then analysed these datasets alongside 66 RNA-Seq datasets from four Pst infection time-courses and 420 Pst-infected plant field and laboratory samples that were publicly available. A database of gene expression values for Pst and wheat was generated for each of these 1024 RNA-Seq datasets and incorporated into the development of the rust expression browser ( http://www.rust-expression.com ). This enables for the first time simultaneous 'point-and-click' access to gene expression profiles for Pst and its wheat host and represents the largest database of processed RNA-Seq datasets available for any of the three Puccinia wheat rust pathogens. We also demonstrated the utility of the browser through investigation of expression of putative Pst virulence genes over time and examined the host plants response to Pst infection., Conclusions: The rust expression browser offers immense value to the wider community, facilitating data sharing and transparency and the underlying database can be continually expanded as more datasets become publicly available.
- Published
- 2021
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5. Optimizing Rhizobium- legume symbioses by simultaneous measurement of rhizobial competitiveness and N 2 fixation in nodules.
- Author
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Mendoza-Suárez MA, Geddes BA, Sánchez-Cañizares C, Ramírez-González RH, Kirchhelle C, Jorrin B, and Poole PS
- Subjects
- Fabaceae metabolism, Fabaceae microbiology, Green Fluorescent Proteins genetics, High-Throughput Nucleotide Sequencing, Nitrogen metabolism, Pisum sativum genetics, Pisum sativum metabolism, Plasmids genetics, Rhizobium leguminosarum metabolism, Root Nodules, Plant genetics, Root Nodules, Plant metabolism, Soil Microbiology, Synthetic Biology, Fabaceae genetics, Nitrogen Fixation genetics, Rhizobium leguminosarum genetics, Symbiosis genetics
- Abstract
Legumes tend to be nodulated by competitive rhizobia that do not maximize nitrogen (N
2 ) fixation, resulting in suboptimal yields. Rhizobial nodulation competitiveness and effectiveness at N2 fixation are independent traits, making their measurement extremely time-consuming with low experimental throughput. To transform the experimental assessment of rhizobial competitiveness and effectiveness, we have used synthetic biology to develop reporter plasmids that allow simultaneous high-throughput measurement of N2 fixation in individual nodules using green fluorescent protein (GFP) and barcode strain identification (Plasmid ID) through next generation sequencing (NGS). In a proof-of-concept experiment using this technology in an agricultural soil, we simultaneously monitored 84 different Rhizobium leguminosarum strains, identifying a supercompetitive and highly effective rhizobial symbiont for peas. We also observed a remarkable frequency of nodule coinfection by rhizobia, with mixed occupancy identified in ∼20% of nodules, containing up to six different strains. Critically, this process can be adapted to multiple Rhizobium -legume symbioses, soil types, and environmental conditions to permit easy identification of optimal rhizobial inoculants for field testing to maximize agricultural yield., Competing Interests: The authors declare no competing interest.- Published
- 2020
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6. BrAPI-an application programming interface for plant breeding applications.
- Author
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Selby P, Abbeloos R, Backlund JE, Basterrechea Salido M, Bauchet G, Benites-Alfaro OE, Birkett C, Calaminos VC, Carceller P, Cornut G, Vasques Costa B, Edwards JD, Finkers R, Yanxin Gao S, Ghaffar M, Glaser P, Guignon V, Hok P, Kilian A, König P, Lagare JEB, Lange M, Laporte MA, Larmande P, LeBauer DS, Lyon DA, Marshall DS, Matthews D, Milne I, Mistry N, Morales N, Mueller LA, Neveu P, Papoutsoglou E, Pearce B, Perez-Masias I, Pommier C, Ramírez-González RH, Rathore A, Raquel AM, Raubach S, Rife T, Robbins K, Rouard M, Sarma C, Scholz U, Sempéré G, Shaw PD, Simon R, Soldevilla N, Stephen G, Sun Q, Tovar C, Uszynski G, and Verouden M
- Subjects
- Genomics, Plant Breeding, Software, User-Computer Interface
- Abstract
Motivation: Modern genomic breeding methods rely heavily on very large amounts of phenotyping and genotyping data, presenting new challenges in effective data management and integration. Recently, the size and complexity of datasets have increased significantly, with the result that data are often stored on multiple systems. As analyses of interest increasingly require aggregation of datasets from diverse sources, data exchange between disparate systems becomes a challenge., Results: To facilitate interoperability among breeding applications, we present the public plant Breeding Application Programming Interface (BrAPI). BrAPI is a standardized web service API specification. The development of BrAPI is a collaborative, community-based initiative involving a growing global community of over a hundred participants representing several dozen institutions and companies. Development of such a standard is recognized as critical to a number of important large breeding system initiatives as a foundational technology. The focus of the first version of the API is on providing services for connecting systems and retrieving basic breeding data including germplasm, study, observation, and marker data. A number of BrAPI-enabled applications, termed BrAPPs, have been written, that take advantage of the emerging support of BrAPI by many databases., Availability and Implementation: More information on BrAPI, including links to the specification, test suites, BrAPPs, and sample implementations is available at https://brapi.org/. The BrAPI specification and the developer tools are provided as free and open source., (© The Author(s) 2019. Published by Oxford University Press.)
- Published
- 2019
- Full Text
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7. SN-38, the active metabolite of irinotecan, inhibits the acute inflammatory response by targeting toll-like receptor 4.
- Author
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Wong DVT, Ribeiro-Filho HV, Wanderley CWS, Leite CAVG, Lima JB, Assef ANB, Cajado AG, Batista GLP, González RH, Silva KO, Borges LPC, Alencar NMN, Wilke DV, Cunha TM, Figueira ACM, Cunha FQ, and Lima-Júnior RCP
- Subjects
- Animals, Humans, Irinotecan pharmacology, Male, Mice, Topoisomerase I Inhibitors pharmacology, Inflammation drug therapy, Irinotecan therapeutic use, Toll-Like Receptor 4 genetics, Topoisomerase I Inhibitors therapeutic use
- Abstract
Purpose: Anticancer-drug efficacy seems to involve the direct interaction with host immune cells. Although topoisomerase I (Top I) inhibitors have been suggested to block LPS-evoked inflammation, the interaction between these drugs and toll-like receptor 4 (TLR4) is unaddressed., Methods: SN-38, the active metabolite of the Top I inhibitor irinotecan, and TLR4 interaction was assessed using the in vitro luciferase nuclear factor-κB reporter assay, neutrophil migration to murine air-pouch, in silico simulation, and the thermal shift assay (TSA). Topotecan was used as a positive anti-inflammatory control., Results: Non-cytotoxic concentrations of SN-38 attenuated LPS (a TLR4 agonist)-driven cell activation without affecting peptidoglycan (a TLR2 agonist)-activating response. Similarly, topotecan also prevented LPS-induced inflammation. Conversely, increasing concentrations of LPS reversed the SN-38 inhibitory effect. In addition, SN-38 abrogated LPS-dependent neutrophil migration and reduced TNF-α, IL-6, and keratinocyte chemoattractant levels in the air-pouch model, but failed to inhibit zymosan (a TLR2 agonist)-induced cell migration. A two-step molecular docking analysis indicated two potential binding sites for the SN-38 in the MD-2/TLR4 complex, the hydrophobic MD-2 pocket (binding energy of - 8.1 kcal/mol) and the rim of the same molecule (- 6.9 kcal/mol). The topotecan also bound to the MD-2 pocket. In addition, not only the lactone forms, but also the carboxylate conformations of both Top I inhibitors interacted with the MD-2 molecule. Furthermore, the TSA suggested the interaction of SN-38 with MD-2., Conclusions: Therefore, SN-38 inhibits acute inflammation by blocking LPS-driven TLR4 signaling. This mechanism seems to be shared by other Top I inhibitors.
- Published
- 2019
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8. Hotspots in the genomic architecture of field drought responses in wheat as breeding targets.
- Author
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Gálvez S, Mérida-García R, Camino C, Borrill P, Abrouk M, Ramírez-González RH, Biyiklioglu S, Amil-Ruiz F, Dorado G, Budak H, Gonzalez-Dugo V, Zarco-Tejada PJ, Appels R, Uauy C, and Hernandez P
- Subjects
- Plant Breeding methods, Quantitative Trait Loci, Transcriptome, Triticum physiology, Droughts, Genome, Plant, Stress, Physiological, Triticum genetics
- Abstract
Wheat can adapt to most agricultural conditions across temperate regions. This success is the result of phenotypic plasticity conferred by a large and complex genome composed of three homoeologous genomes (A, B, and D). Although drought is a major cause of yield and quality loss in wheat, the adaptive mechanisms and gene networks underlying drought responses in the field remain largely unknown. Here, we addressed this by utilizing an interdisciplinary approach involving field water status phenotyping, sampling, and gene expression analyses. Overall, changes at the transcriptional level were reflected in plant spectral traits amenable to field-level physiological measurements, although changes in photosynthesis-related pathways were found likely to be under more complex post-transcriptional control. Examining homoeologous genes with a 1:1:1 relationship across the A, B, and D genomes (triads), we revealed a complex genomic architecture for drought responses under field conditions, involving gene homoeolog specialization, multiple gene clusters, gene families, miRNAs, and transcription factors coordinating these responses. Our results provide a new focus for genomics-assisted breeding of drought-tolerant wheat cultivars.
- Published
- 2019
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9. Genome-Wide Transcription During Early Wheat Meiosis Is Independent of Synapsis, Ploidy Level, and the Ph1 Locus.
- Author
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Martín AC, Borrill P, Higgins J, Alabdullah A, Ramírez-González RH, Swarbreck D, Uauy C, Shaw P, and Moore G
- Abstract
Polyploidization is a fundamental process in plant evolution. One of the biggest challenges faced by a new polyploid is meiosis, particularly discriminating between multiple related chromosomes so that only homologous chromosomes synapse and recombine to ensure regular chromosome segregation and balanced gametes. Despite its large genome size, high DNA repetitive content and similarity between homoeologous chromosomes, hexaploid wheat completes meiosis in a shorter period than diploid species with a much smaller genome. Therefore, during wheat meiosis, mechanisms additional to the classical model based on DNA sequence homology, must facilitate more efficient homologous recognition. One such mechanism could involve exploitation of differences in chromosome structure between homologs and homoeologs at the onset of meiosis. In turn, these chromatin changes, can be expected to be linked to transcriptional gene activity. In this study, we present an extensive analysis of a large RNA-seq data derived from six different genotypes: wheat, wheat-rye hybrids and newly synthesized octoploid triticale, both in the presence and absence of the Ph1 locus. Plant material was collected at early prophase, at the transition leptotene-zygotene, when the telomere bouquet is forming and synapsis between homologs is beginning. The six genotypes exhibit different levels of synapsis and chromatin structure at this stage; therefore, recombination and consequently segregation, are also different. Unexpectedly, our study reveals that neither synapsis, whole genome duplication nor the absence of the Ph1 locus are associated with major changes in gene expression levels during early meiotic prophase. Overall wheat transcription at this meiotic stage is therefore highly resilient to such alterations, even in the presence of major chromatin structural changes. Further studies in wheat and other polyploid species will be required to reveal whether these observations are specific to wheat meiosis.
- Published
- 2018
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10. The transcriptional landscape of polyploid wheat.
- Author
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Ramírez-González RH, Borrill P, Lang D, Harrington SA, Brinton J, Venturini L, Davey M, Jacobs J, van Ex F, Pasha A, Khedikar Y, Robinson SJ, Cory AT, Florio T, Concia L, Juery C, Schoonbeek H, Steuernagel B, Xiang D, Ridout CJ, Chalhoub B, Mayer KFX, Benhamed M, Latrasse D, Bendahmane A, Wulff BBH, Appels R, Tiwari V, Datla R, Choulet F, Pozniak CJ, Provart NJ, Sharpe AG, Paux E, Spannagl M, Bräutigam A, and Uauy C
- Subjects
- Bread, Gene Expression Profiling, Gene Expression Regulation, Developmental, Genome, Plant, RNA, Plant genetics, Sequence Analysis, RNA, Triticum growth & development, Gene Expression Regulation, Plant, Polyploidy, Transcription, Genetic, Triticum genetics
- Abstract
The coordinated expression of highly related homoeologous genes in polyploid species underlies the phenotypes of many of the world's major crops. Here we combine extensive gene expression datasets to produce a comprehensive, genome-wide analysis of homoeolog expression patterns in hexaploid bread wheat. Bias in homoeolog expression varies between tissues, with ~30% of wheat homoeologs showing nonbalanced expression. We found expression asymmetries along wheat chromosomes, with homoeologs showing the largest inter-tissue, inter-cultivar, and coding sequence variation, most often located in high-recombination distal ends of chromosomes. These transcriptionally dynamic genes potentially represent the first steps toward neo- or subfunctionalization of wheat homoeologs. Coexpression networks reveal extensive coordination of homoeologs throughout development and, alongside a detailed expression atlas, provide a framework to target candidate genes underpinning agronomic traits in wheat., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
- Published
- 2018
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11. Impact of transposable elements on genome structure and evolution in bread wheat.
- Author
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Wicker T, Gundlach H, Spannagl M, Uauy C, Borrill P, Ramírez-González RH, De Oliveira R, Mayer KFX, Paux E, and Choulet F
- Subjects
- Base Sequence, Bread, Chromosomes, Plant genetics, DNA, Intergenic genetics, Diploidy, Gene Expression Regulation, Plant, Genes, Plant, Mutagenesis, Insertional genetics, Promoter Regions, Genetic genetics, Terminal Repeat Sequences genetics, Tetraploidy, DNA Transposable Elements genetics, Evolution, Molecular, Genome, Plant, Triticum genetics
- Abstract
Background: Transposable elements (TEs) are major components of large plant genomes and main drivers of genome evolution. The most recent assembly of hexaploid bread wheat recovered the highly repetitive TE space in an almost complete chromosomal context and enabled a detailed view into the dynamics of TEs in the A, B, and D subgenomes., Results: The overall TE content is very similar between the A, B, and D subgenomes, although we find no evidence for bursts of TE amplification after the polyploidization events. Despite the near-complete turnover of TEs since the subgenome lineages diverged from a common ancestor, 76% of TE families are still present in similar proportions in each subgenome. Moreover, spacing between syntenic genes is also conserved, even though syntenic TEs have been replaced by new insertions over time, suggesting that distances between genes, but not sequences, are under evolutionary constraints. The TE composition of the immediate gene vicinity differs from the core intergenic regions. We find the same TE families to be enriched or depleted near genes in all three subgenomes. Evaluations at the subfamily level of timed long terminal repeat-retrotransposon insertions highlight the independent evolution of the diploid A, B, and D lineages before polyploidization and cases of concerted proliferation in the AB tetraploid., Conclusions: Even though the intergenic space is changed by the TE turnover, an unexpected preservation is observed between the A, B, and D subgenomes for features like TE family proportions, gene spacing, and TE enrichment near genes.
- Published
- 2018
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12. Molecular epidemiology of Clostridium difficile infection in a Brazilian cancer hospital.
- Author
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Costa CL, Mano de Carvalho CB, González RH, Gifoni MAC, Ribeiro RA, Quesada-Gómez C, and Brito GAC
- Subjects
- Adult, Aged, Aged, 80 and over, Anti-Bacterial Agents pharmacology, Brazil epidemiology, Comorbidity, Female, Hospitalization, Humans, Male, Microbial Sensitivity Tests, Middle Aged, Molecular Epidemiology, Molecular Typing, Public Health Surveillance, Ribotyping, Cancer Care Facilities, Clostridioides difficile classification, Clostridioides difficile drug effects, Clostridioides difficile genetics, Clostridium Infections epidemiology, Clostridium Infections microbiology, Cross Infection
- Abstract
Clostridium difficile is a Gram-positive spore forming anaerobic bacterium and the main cause of healthcare-associated diarrhea. This study aimed to perform the phenotypic characterization and molecular typing of Clostridium difficile isolates among patients at a cancer hospital in Brazil. During 18 months, 48 diarrheic fecal samples were collected, of these 48% were positive in either one or both of the performed tests: detection of toxins A/B and culture. Clostridium difficile was recovered from four samples (17%). All strains carried toxin A and B genes, and the isolates belonged to PCR-ribotype 014/020, PGFE-type NAP4 and toxinotype XVIII. On the other hand, one isolate belonged to a novel PCR-ribotype, and PFGE-type, likewise to toxinotype IXb. The isolates showed susceptibility to metronidazole, vancomycin and moxifloxacin, and were resistant to ciprofloxacin. Finally, the findings indicate high positivity between the samples tested, suggesting an expressive importance of this infection, including detection of a novel ribotype/PFGE-type of Clostridium difficile, and show for the first time the detection of community-associated Clostridium difficile infection (CA-CDI) in these patients in Northeast Brazil. These data emphasize the importance to a better understanding of the epidemiological situation of this infection in Brazilian hospitals., (Copyright © 2017. Published by Elsevier Ltd.)
- Published
- 2017
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13. Community-acquired diarrhea associated with Clostridium difficile in an HIV-positive cancer patient: first case report in Latin America.
- Author
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Costa CL, Quesada-Gómez C, de Carvalho CB, González RH, Gifoni MA, Ribeiro RA, and de Castro Brito GA
- Subjects
- Aged, Brazil, Clostridium Infections complications, Community-Acquired Infections complications, Diarrhea complications, Diarrhea microbiology, Female, Humans, Clostridioides difficile isolation & purification, Clostridium Infections diagnosis, Community-Acquired Infections diagnosis, Diarrhea diagnosis, HIV Seropositivity complications, Neoplasms complications
- Abstract
Clostridium difficile is the most important cause of nosocomial diarrhea, mainly associated with antibiotic use and immunodeficiency. Although, an increased incidence of community-acquired C. difficile infection (CA-CDI) has been reported worldwide, this infection has been under-diagnosed in Latin America. This is the first report of a CA-CDI case in Latin America, in an HIV-positive patient with cancer., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2014
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14. Blue-light-dependent inhibition of twitching motility in Acinetobacter baylyi ADP1: additive involvement of three BLUF-domain-containing proteins.
- Author
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Bitrian M, González RH, Paris G, Hellingwerf KJ, and Nudel CB
- Subjects
- Acinetobacter classification, Acinetobacter metabolism, Amino Acid Sequence, Bacterial Proteins genetics, Light, Molecular Sequence Data, Phylogeny, Protein Structure, Tertiary, Sequence Alignment, Acinetobacter cytology, Acinetobacter radiation effects, Bacterial Proteins chemistry, Bacterial Proteins metabolism
- Abstract
Twitching motility in Acinetobacter baylyi ADP1 is inhibited by moderate intensities of blue light in a temperature-dependent manner (maximally at 20 °C). We analysed the involvement of four predicted blue-light sensing using flavin (BLUF)-domain-containing proteins encoded in the genome of this strain in the twitching motility phenotype. All four genes were expressed both in light and in darkness. A phylogenetic tree showed that one BLUF domain, ACIAD2110, grouped separately from the other three (ACIAD1499, ACIAD2125 and ACIAD2129). Individual knockout mutants of the latter three, but not of ACIAD2110, fully abolished the light dependency of the twitching motility response. Quantitative analysis of transcript level of the three genes showed a decreased expression in the light, with dark/light ratios of 1.65±0.28, 1.79±0.21 and 2.69±0.39, for ACIAD2125, ACIAD2129 and ACIAD1499, respectively. Double and triple knockouts of ACIAD1499, ACIAD2125 and ACIAD2129 confirmed the same phenotype as the corresponding single knockouts. Complementation of all the single knockouts and the triple knockout mutants with any of the three BLUF-domain-encoding genes fully restored the inhibition of twitching motility by blue light that is observed in the wild-type strain. A. baylyi ADP1 therefore shows a high degree of redundancy in the genes that encode BLUF-containing photoreceptors. Moreover, all plasmid-complemented strains, expressing any of the BLUF proteins irrespective of the specific set of deleted photoreceptors, displayed increased light-dependent inhibition of twitching motility, as compared to the wild-type (P<0.001). We conclude that the three genes ACIAD1499, ACIAD2125 and ACIAD2129 are jointly required to inhibit twitching motility under moderate blue-light illumination.
- Published
- 2013
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15. Identification of virulence markers in clinically relevant strains of Acinetobacter genospecies.
- Author
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Bitrian M, Solari CM, González RH, and Nudel CB
- Subjects
- Acinetobacter genetics, Acinetobacter metabolism, Acinetobacter Infections metabolism, Acyl-Butyrolactones metabolism, Amino Acid Sequence, Bacterial Proteins genetics, Bacterial Proteins metabolism, Base Sequence, Biofilms growth & development, Cross Infection metabolism, DNA, Bacterial chemistry, DNA, Bacterial genetics, Humans, Molecular Sequence Data, Phylogeny, Polymerase Chain Reaction, Quorum Sensing physiology, RNA, Ribosomal, 16S chemistry, RNA, Ribosomal, 16S genetics, Repressor Proteins genetics, Repressor Proteins metabolism, Sequence Alignment, Sequence Analysis, DNA, Trans-Activators genetics, Trans-Activators metabolism, Transcription Factors genetics, Transcription Factors metabolism, Virulence, Acinetobacter pathogenicity, Acinetobacter Infections microbiology, Cross Infection microbiology
- Abstract
Nine Acinetobacter strains from patients and hospital environment were analyzed for virulence markers, quorum sensing signal production, and the presence of luxI and luxR genes. The strains had several properties in common: growth in iron limited condition, biofilm formation, and no active protease secretion. Significantly higher catechol production was determined in patient isolates (P < 0.03), but other invasiveness markers, such as lipase secretion, amount of biofilm, cell motility, antibiotic resistance, and hemolysin production, showed large variability. Notably, all members of the so-called A. calcoaceticus-A. baumannii complex, regardless of whether the source was a patient or environmental, secreted mediumto long-chain N-acyl homoserine lactones (AHL) and showed blue light inhibition of cell motility. In these strains, a luxI homologue with a homoserine lactone synthase domain and a luxR putative regulator displaying the typical AHL binding domain were identified.
- Published
- 2012
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16. Extended endoscopic endonasal approach to the skull base.
- Author
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Arbolay OL, González JG, González RH, and Gálvez YH
- Subjects
- Adenoma surgery, Adult, Chordoma surgery, Craniopharyngioma surgery, Female, Humans, Male, Middle Aged, Pituitary Neoplasms surgery, Retrospective Studies, Treatment Outcome, Brain Neoplasms surgery, Endoscopy methods, Minimally Invasive Surgical Procedures methods, Neurosurgical Procedures methods, Skull Base surgery
- Abstract
Objective: Different approaches to the skull base have been developed through the sphenoidal sinus. Traditional boundaries of the trans-sphenoidal approach can be extended in antero-posterior and lateral planes. We review our experience with the extended endoscopic endonasal approach in the first 12 cases., Methods: We used the extended endoscopic endonasal approach in 12 patients with different lesions of the skull base. This study specifically focuses on the type of lesions, surgical approach, outcome and surgical complications., Results: The extended endoscopic endonasal approach was used in 12 patients with the following lesions: 4 invasive adenomas to the cavernous sinus, 2 clival chordomas, 2 craniopharyngiomas, 1 hypothalamic astrocytoma and 3 pituitary adenomas extended upon the tuberculum. Gross total resection was achieved in 8 cases (66.7%) subtotal resection in 3 and just a biopsy could be accomplished in the case of astrocytoma. This last patient developed meningo-encephalitis and died two weeks later., Conclusions: The extended endoscopic endonasal approach is a promising minimally invasive alternative for selected cases with sellar, parasellar or clivus lesions. As techniques and technology advance, this approach may become the procedure of choice for most lesions and should be considered an option in the management of the patients with these complex pathologies by skull base surgeons., (Copyright Georg Thieme Verlag KG Stuttgart. New York.)
- Published
- 2009
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17. Quorum sensing signal profile of Acinetobacter strains from nosocomial and environmental sources.
- Author
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González RH, Dijkshoorn L, Van den Barselaar M, and Nudel C
- Subjects
- Acinetobacter chemistry, Acinetobacter genetics, Acinetobacter isolation & purification, Chromatography, Thin Layer, Humans, Species Specificity, Acinetobacter physiology, Acinetobacter Infections microbiology, Acyl-Butyrolactones analysis, Cross Infection microbiology, Environmental Microbiology, Quorum Sensing physiology
- Abstract
A set of 43 strains corresponding to 20 classified and unclassified genomic Acinetobacter species was analyzed for the production of typical N-acyl homoserine lactone quorum sensing molecules in culture broths. A large percentage of the strains (74%) displayed quorum sensing signals that could be separated into three statistically significantly different chromatographic groups (p < 0.001) based on their retention factor in TLC, i.e., Rf1 (0.22 +/- 0.02); Rf2 (0.40 +/- 0.02) and Rf3 (0.54 +/- 0.02). Noteworthy, 63% of the strains tested produced more than one quorum signal. The frequency of signal appearance was Rf3 > Rf2 > Rf1. None of the three signals could be specifically assigned to a particular species in the genus; furthermore, no distinction could be made between the quorum sensing signals secreted by typical opportunistic strains of the A. calcoaceticus-A. baumannii complex, isolated from patients, with respect to the other species of the genus, except for the Rf1 signal which was present in all the QS positive strains belonging to this complex and DNA group 13 TU. In conclusion, quorum sensors in Acinetobacter are not homogenously distributed among species and one of them is present in most of the A. calcoaceticus-baumannii complex.
- Published
- 2009
18. [Luminiscence: reaching the quorum for shining].
- Author
-
González RH
- Subjects
- Aliivibrio fischeri physiology, Luminescence, Quorum Sensing, Vibrio physiology
- Published
- 2008
19. Cerebellopontine angle cysticercus and concurrent vascular compression in a case of trigeminal neuralgia.
- Author
-
Revuelta R, Soto-Hernández JL, Vales LO, and González RH
- Subjects
- Arteries surgery, Cerebellar Diseases complications, Cerebellar Diseases surgery, Decompression, Surgical, Diagnosis, Differential, Female, Humans, Middle Aged, Neurocysticercosis complications, Neurocysticercosis surgery, Radiculopathy surgery, Tissue Adhesions surgery, Trigeminal Nerve Diseases surgery, Trigeminal Neuralgia surgery, Cerebellar Diseases diagnosis, Cerebellopontine Angle blood supply, Cerebellopontine Angle surgery, Cerebellum blood supply, Neurocysticercosis diagnosis, Radiculopathy diagnosis, Trigeminal Nerve Diseases diagnosis, Trigeminal Neuralgia etiology
- Abstract
The authors present the case of a 59-year-old woman with an 8 months history of lancinating pain and hyphestesia on the right side of the face along with hearing impairment. She had poor tolerance to carbamazepine. A non-enhancing cystic image was observed at the right cerebellopontine angle on magnetic resonance imaging. The patient underwent surgery. Through a right retromastoid minicraniectomy and under microscopic magnification the VII and VIII cranial nerve complex was found involved by multiple adhesions around a cysticercus. After the cyst was removed a loop of the anteroinferior cerebellar artery was identified compressing the V right nerve at its root entry zone. Decompression was performed by the insertion of a Teflon implant. The postoperative course was uneventful and trigeminal neuralgia (TN) disappeared after surgery. Five previous cases of cranial nerve hyperactive dysfunction syndromes, four of trigeminal neuralgia and one of hemifacial spasm associated to cerebellopontine angle cysticercosis are briefly commented. We suggest that in some of these cases microvascular compression was probably present, and during surgery of cerebellopontine angle cysticercus by either trigeminal neuralgia or hemifacial spasm, vascular compression must be carefully searched and treated when found.
- Published
- 2003
- Full Text
- View/download PDF
20. New approaches to the management of peripheral vertigo: efficacy and safety of two calcium antagonists in a 12-week, multinational, double-blind study.
- Author
-
Pianese CP, Hidalgo LO, González RH, Madrid CE, Ponce JE, Ramírez AM, Morán LM, Arenas JE, Rubio AT, Uribe JO, Abiuso J, Hanuch E, Alegría J, Volpi C, Flaskamp R, Sanjuán AP, Gómez JM, Hernández J, Pedraza A, Quijano D, Martínez C, Castañeda JR, Guerra OJ, and F GV
- Subjects
- Adult, Aged, Aged, 80 and over, Calcium Channel Blockers adverse effects, Calcium Channel Blockers therapeutic use, Cinnarizine administration & dosage, Cinnarizine adverse effects, Drug Administration Schedule, Electronystagmography, Female, Humans, International Cooperation, Male, Middle Aged, Nimodipine administration & dosage, Nimodipine adverse effects, Pilot Projects, Recurrence, Severity of Illness Index, Vertigo physiopathology, Calcium Channel Blockers administration & dosage, Cinnarizine therapeutic use, Nimodipine therapeutic use, Vertigo drug therapy
- Abstract
Objective: To evaluate the efficacy and safety profile of one 30-mg nimodipine oral tablet taken three times per day (one tablet with breakfast, one with lunch, and one with dinner) or one 150-mg cinnarizine verum oral capsule taken once each day with dinner for 12 weeks., Study Design: Comparative in a double-blind, multinational pilot study., Setting: Tertiary referral center., Patients: A total of 221 patients met the study criteria; of that total, 181 adult patients completed the study, including 135 women and 46 men whose ages ranged from 20 to 80 years., Interventions: Two calcium antagonists were used to treat vertigo (nimodipine, 89 patients; cinnarizine, 92 patients), and all patients were maintained on the same dosage regimen until they completed 12 weeks of treatment. Patients were evaluated at 2-and 4-week intervals; an additional evaluation was made at Week 14 to determine vertigo recurrence in the posttreatment period., Main Outcome Measures: The response was evaluated by using the vertigo severity index, a count of vertigo episodes in a given time period. Each episode is weighted according to its intensity., Results: Nimodipine treatment decreased the incidence of moderate vertigo episodes by 78.8% and decreased severe vertigo episodes by 85.0%. Cinnarizine treatment decreased the incidence of moderate vertigo episodes by 65.8% and decreased severe vertigo episodes by 89.8%. Nimodipine and cinnarizine exhibited similar safety profiles. Only two patients withdrew from the study because of adverse events possibly related to the study drug. One patient withdrew from the cinnarizine group because of headache, and one patient withdrew from the nimodipine group because of lipothymia., Conclusion: These data confirm the marked efficacy of both nimodipine and cinnarizine in the treatment of vestibular vertigo.
- Published
- 2002
- Full Text
- View/download PDF
21. Detection and characterization of quorum sensing signal molecules in Acinetobacter strains.
- Author
-
González RH, Nusblat A, and Nudel BC
- Subjects
- Acinetobacter growth & development, Biosensing Techniques, Chromatography, Thin Layer, Culture Media, Conditioned, Homoserine analogs & derivatives, Homoserine analysis, Homoserine metabolism, Humans, Lactones analysis, Lactones metabolism, Signal Transduction, Time Factors, Acinetobacter metabolism
- Abstract
Quorum sensing is a widespread regulatory mechanism among Gram-negative bacteria. In this study, Acinetobacter strains were assayed for the presence of quorum sensing signal molecules capable of activating N-acylhomoserine lactone biosensors. By using an Agrobacterium tumefaciens reporter strain it was shown that all the cultures produced two to four detectable signal molecules with different chromatographic patterns. In A. calcoaceticus BD413 supernatants four compounds were detected in a time-dependent manner, and maximal activity was reached at stationary phase. The number of signal molecules was dependent on medium composition; typically, cultures in minimal medium displayed one or two more signals, as compared to complex medium. None of the Acinetobacter supematants showed autoinduction activity with an Chromobacterium violaceum reporter strain, neither in direct or competition assays.
- Published
- 2001
- Full Text
- View/download PDF
22. Resource concentration hypothesis: effect of host plant patch size on density of herbivorous insects.
- Author
-
Grez AA and González RH
- Abstract
The resource concentration hypothesis (Root 1973) predicts that specialist herbivorous insects should be more abundant in large patches of host plants, because the insects are more likely to find and stay longer in those patches. Between August 1989 and January 1990 we experimentally tested Root's hypothesis by analyzing the numerical response of four species of herbivorous insects associated with patches of 4, 16, 64 and 225 cabbage plants, Brassica oleracea var. capitata. In addition, we studied the colonization of patches by adults of Plutella xylostella (L.) (Lepidoptera: Plutellidae), and the migration of their larvae in patches of different sizes. No herbivorous insect densities differed significantly with patch size. Adults of P. xylostella colonized all kind of patches equally. Larvae did not migrate between patches, and their disappearance rate did not differ between patches. The resource concentration hypothesis is organism-dependent, being a function of the adult and juvenile herbivore dispersal behavior in relation to the spatial scale of patchiness.
- Published
- 1995
- Full Text
- View/download PDF
23. [Study of a case of septicemia caused by Torulopsis glabrata].
- Author
-
Negroni R, De Obrutsky CW, and González RH
- Subjects
- Adolescent, Female, Humans, Amphotericin B therapeutic use, Anti-Bacterial Agents therapeutic use, Cryptococcosis complications, Postoperative Complications, Sepsis etiology, Thymectomy
- Published
- 1965
24. [Spontaneous recurrent bilateral pneumothorax. Surgical therapy. Results after 5 years].
- Author
-
Villegas AH and González RH
- Subjects
- Adult, Female, Humans, Pneumothorax surgery, Pneumothorax pathology
- Published
- 1967
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