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1.
J Pharm Sci ; 109(4): 1509-1518, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31884015

RESUMO

Cediranib maleate is an active pharmaceutical ingredient (API) in phase III of development within AstraZeneca's oncology portfolio. Analysis of the crystal structure of this API confirmed that the selected salt form was robust. The salt formation step had to be redesigned to avoid an unwanted metastable polymorph. A solvate with a twist appeared during later development and was avoided using insights gained from its crystal structure. Differences between predicted and experimental aspect ratios correlate with weaker crystal interactions. Acceptable variability in particle size was defined and accommodated. The "Matwall" is introduced as a tool for building control of API performance from the crystal structure upward.


Assuntos
Preparações Farmacêuticas , Cristalização , Maleatos , Tamanho da Partícula , Quinazolinas
2.
Nano Lett ; 19(11): 7563-7572, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30958010

RESUMO

A primary limitation to real-time imaging of metabolites and proteins has been the selective detection of biomolecules that have no naturally occurring or stable molecular recognition counterparts. We present developments in the design of synthetic near-infrared fluorescent nanosensors based on the fluorescence modulation of single-walled carbon nanotubes (SWNTs) with select sequences of surface-adsorbed N-substituted glycine peptoid polymers. We assess the stability of the peptoid-SWNT nanosensor candidates under variable ionic strengths, protease exposure, and cell culture media conditions and find that the stability of peptoid-SWNTs depends on the composition and length of the peptoid polymer. From our library, we identify a peptoid-SWNT assembly that can detect lectin protein wheat germ agglutinin (WGA) with a sensitivity comparable to the concentration of serum proteins. To demonstrate the retention of nanosensor-bound protein activity, we show that WGA on the nanosensor produces an additional fluorescent signal modulation upon exposure to the lectin's target sugars, suggesting the lectin protein remains active and selectively binds its target sugars through ternary molecular recognition interactions relayed to the nanosensor. Our results inform design considerations for developing synthetic molecular recognition elements by assembling peptoid polymers on SWNTs and also demonstrate these assemblies can serve as optical nanosensors for lectin proteins and their target sugars. Together, these data suggest certain peptoid sequences can be assembled with SWNTs to serve as versatile optical probes to detect proteins and their molecular substrates.


Assuntos
Nanotubos de Carbono/química , Peptoides/química , Açúcares/análise , Aglutininas do Germe de Trigo/análise , Adsorção , Técnicas Biossensoriais/métodos , Fluorescência , Modelos Moleculares , Nanotecnologia/métodos , Polímeros/química , Imagem Individual de Molécula/métodos , Eletricidade Estática
3.
J Org Chem ; 84(8): 4754-4762, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30404447

RESUMO

The final synthetic step in the synthesis of cediranib, AZD2171, 1, is the alkylation of a phenol with an alkyl halide to generate an ether. Our need to understand and control the formation of synthetic impurities generated in this step of the synthesis led us to investigate the kinetics and mechanism of the alkylation of indolphenol, 2, 4-[(4-fluoro-2-methyl-1 H-indol-5-yl)oxy]-6-methoxyquinazolin-7-ol, by chloropyrrolidine, 3, 1-(3-chloropropyl)pyrrolidine. Studies in 1-methyl-2-pyrrolidinone (NMP) established that the active alkylating agent is the azetidinium ion, 4, 4-azoniaspiro[3.4]octane, formed via a slow intramolecular cyclization reaction of chloropyrrolidine, 3. The azetidinium ion was isolated as its tetraphenylborate salt from water by heating 3 in the presence of aqueous potassium tetraphenyl borate, and its competence as an intermediate was demonstrated by its fast reaction with 2 to yield cediranib, 1.

4.
Nano Res ; 11(10): 5144-5172, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31105899

RESUMO

Microscopic imaging of the brain continues to reveal details of its structure, connectivity, and function. To further improve our understanding of the emergent properties and functions of neural circuits, new methods are necessary to directly visualize the relationship between brain structure, neuron activity, and neurochemistry. Advances in engineering the chemical and optical properties of nanomaterials concurrent with developments in deep-tissue microscopy hold tremendous promise for overcoming the current challenges associated with in vivo brain imaging, particularly for imaging the brain through optically-dense brain tissue, skull, and scalp. To this end, developments in nanomaterials offer much promise toward implementing tunable chemical functionality for neurochemical targeting and sensing, and fluorescence stability for long-term imaging. In this review, we summarize current brain microscopy methods and describe the diverse classes of nanomaterials recently leveraged as contrast agents and functional probes for microscopic optical imaging of the brain.

5.
ACS Chem Neurosci ; 8(10): 2275-2289, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-28714693

RESUMO

Imaging the dynamic behavior of neuromodulatory neurotransmitters in the extracelluar space that arise from individual quantal release events would constitute a major advance in neurochemical imaging. Spatial and temporal resolution of these highly stochastic neuromodulatory events requires concurrent advances in the chemical development of optical nanosensors selective for neuromodulators in concert with advances in imaging methodologies to capture millisecond neurotransmitter release. Herein, we develop and implement a stochastic model to describe dopamine dynamics in the extracellular space (ECS) of the brain dorsal striatum to guide the design and implementation of fluorescent neurochemical probes that record neurotransmitter dynamics in the ECS. Our model is developed from first-principles and simulates release, diffusion, and reuptake of dopamine in a 3D simulation volume of striatal tissue. We find that in vivo imaging of neuromodulation requires simultaneous optimization of dopamine nanosensor reversibility and sensitivity: dopamine imaging in the striatum or nucleus accumbens requires nanosensors with an optimal dopamine dissociation constant (Kd) of 1 µM, whereas Kds above 10 µM are required for dopamine imaging in the prefrontal cortex. Furthermore, as a result of the probabilistic nature of dopamine terminal activity in the striatum, our model reveals that imaging frame rates of 20 Hz are optimal for recording temporally resolved dopamine release events. Our work provides a modeling platform to probe how complex neuromodulatory processes can be studied with fluorescent nanosensors and enables direct evaluation of nanosensor chemistry and imaging hardware parameters. Our stochastic model is generic for evaluating fluorescent neurotransmission probes, and is broadly applicable to the design of other neurotransmitter fluorophores and their optimization for implementation in vivo.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Espaço Extracelular/metabolismo , Corantes Fluorescentes , Animais , Neurotransmissores/metabolismo , Córtex Pré-Frontal/metabolismo , Transmissão Sináptica/fisiologia
6.
Biology (Basel) ; 5(3)2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27490579

RESUMO

Species of the Fe/Mn-oxidizing bacteria Leptothrix produce tremendous amounts of microtubular, Fe/Mn-encrusted sheaths within a few days in outwells of groundwater that can rapidly clog water systems. To understand this mode of rapid sheath production and define the timescales involved, behaviors of sheath-forming Leptothrix sp. strain OUMS1 were examined using time-lapse video at the initial stage of sheath formation. OUMS1 formed clumps of tangled sheaths. Electron microscopy confirmed the presence of a thin layer of bacterial exopolymer fibrils around catenulate cells (corresponding to the immature sheath). In time-lapse videos, numerous sheath filaments that extended from the periphery of sheath clumps repeatedly fragmented at the apex of the same fragment, the fragments then aggregated and again elongated, eventually forming a large sheath clump comprising tangled sheaths within two days. In this study, we found that fast microscopic fragmentation, dissociation, re-aggregation and re-elongation events are the basis of the rapid, massive production of Leptothrix sheaths typically observed at macroscopic scales.

7.
Biology (Basel) ; 5(2)2016 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-27271677

RESUMO

Bacteria classified in species of the genus Leptothrix produce extracellular, microtubular, Fe-encrusted sheaths. The encrustation has been previously linked to bacterial Fe oxidases, which oxidize Fe(II) to Fe(III) and/or active groups of bacterial exopolymers within sheaths to attract and bind aqueous-phase inorganics. When L. cholodnii SP-6 cells were cultured in media amended with high Fe(II) concentrations, Fe(III) precipitates visibly formed immediately after addition of Fe(II) to the medium, suggesting prompt abiotic oxidation of Fe(II) to Fe(III). Intriguingly, these precipitates were deposited onto the sheath surface of bacterial cells as the population was actively growing. When Fe(III) was added to the medium, similar precipitates formed in the medium first and were abiotically deposited onto the sheath surfaces. The precipitates in the Fe(II) medium were composed of assemblies of globular, amorphous particles (ca. 50 nm diameter), while those in the Fe(III) medium were composed of large, aggregated particles (≥3 µm diameter) with a similar amorphous structure. These precipitates also adhered to cell-free sheaths. We thus concluded that direct abiotic deposition of Fe complexes onto the sheath surface occurs independently of cellular activity in liquid media containing Fe salts, although it remains unclear how this deposition is associated with the previously proposed mechanisms (oxidation enzyme- and/or active group of organic components-involved) of Fe encrustation of the Leptothrix sheaths.

8.
Foods ; 5(4)2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28231177

RESUMO

Until about 1900, large proportions of the world population endured hunger and poverty. The 20th century saw world population increase from 1.6 to 6.1 billion, accompanied and to some extent made possible by rapid improvements in health standards and food supply, with associated advances in agricultural and nutrition sciences. In this paper, I use the application of linear programming (LP) in preparation of rations for farm animals to illustrate a method of calculating the lowest cost of a human diet selected from locally available food items, constrained to provide recommended levels of food energy and nutrients; then, to find a realistic minimum cost, I apply the further constraint that the main sources of food energy in the costed diet are weighted in proportion to the actual reported consumption of food items in that area. Worldwide variations in dietary preferences raise the issue as to the sustainability of popular dietary regimes, and the paper reviews the factors associated with satisfying requirements for adequate nutrition within those regimes. The ultimate physical constraints on food supply are described, together with the ways in which climate change may affect those constraints. During the 20th century, food supply increased sufficiently in most areas to keep pace with the rapid increase in world population. Many challenges will need to be overcome if food supply is to continue to meet demand, and those challenges are made more severe by rising expectations of quality of life in the developing world, as well as by the impacts of climate change on agriculture and aquaculture.

9.
Lancet ; 385 Suppl 1: S62, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26312884

RESUMO

BACKGROUND: Cell origin of aldosterone-producing adenomas, a major cause of hypertension, is unknown. A less common subtype of these adenomas, composed of cells resembling zona glomerulosa, have mutations in genes ATP1A1 and CACNA1D. To understand whether the adenomas originate from zona glomerulosa, we carried out a microarray analysis comparing transcriptomes of zona glomerulosa, zona fasciculata, and tumour in human adrenal tissue, and investigated the functional role of genes upregulated in the zona glomerulosa. METHODS: Using a microarray analysis (Affymetrix, High Wycombe, UK), we compared transcriptomes of zona glomerulosa, zona fasciculata, and tumour obtained by laser capture microdissection of 14 patients with aldestosterone adenomas and seven with phaeochromocytoma. One of the most zona glomerulosa-selective genes was ANO4, a member of the anoctamin family. Subcellular localisation was observed by immunofluorescence microscopy of transfected HEK293 cells. Yellow fluorescent protein-based assay was performed to detect ANO4 activity as a calcium-activated chloride channel. H295R cells were transfected by ANO4 to measure aldosterone and CYP11B2 expression. FINDINGS: Microarray analysis revealed 28 genes that were at least five times overexpressed in zona glomerulosa compared with zona fasciculata. ANO4 was 19·9 times higher in zona glomerulosa than in zona fasciculata (p=6·6 × 10(-24)). Haemagglutinin-tagged ANO4 was localised to the plasma membrane of transfected HEK293 cells. In response to increased intracellular calcium, ANO4-transfected cells triggered a lower flow of iodide than did other anoctamins. ANO4 overexpression in H295R cells increased aldosterone secretion from mean 0·9 pmol/µg protein (SE 0·2) to 1·1 (0·1), whereas CYP11B2 mRNA expression increased five times. INTERPRETATION: We show that ANO4 is one of the most highly expressed genes in zona glomerulosa of the human adrenal gland. When overexpressed in vitro, it increases aldosterone production. FUNDING: British Heart Foundation.

10.
Hypertension ; 65(5): 1103-10, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25776071

RESUMO

Common somatic mutations in CACNAID and ATP1A1 may define a subgroup of smaller, zona glomerulosa (ZG)-like aldosterone-producing adenomas. We have therefore sought signature ZG genes, which may provide insight into the frequency and pathogenesis of ZG-like aldosterone-producing adenomas. Twenty-one pairs of zona fasciculata and ZG and 14 paired aldosterone-producing adenomas from 14 patients with Conn's syndrome and 7 patients with pheochromocytoma were assayed by the Affymetrix Human Genome U133 Plus 2.0 Array. Validation by quantitative real-time polymerase chain reaction was performed on genes >10-fold upregulated in ZG (compared with zona fasciculata) and >10-fold upregulated in aldosterone-producing adenomas (compared with ZG). DACH1, a gene associated with tumor progression, was further analyzed. The role of DACH1 on steroidogenesis, transforming growth factor-ß, and Wnt signaling activity was assessed in the human adrenocortical cell line, H295R. Immunohistochemistry confirmed selective expression of DACH1 in human ZG. Silencing of DACH1 in H295R cells increased CYP11B2 mRNA levels and aldosterone production, whereas overexpression of DACH1 decreased aldosterone production. Overexpression of DACH1 in H295R cells activated the transforming growth factor-ß and canonical Wnt signaling pathways but inhibited the noncanonical Wnt signaling pathway. Stimulation of primary human adrenal cells with angiotensin II decreased DACH1 mRNA expression. Interestingly, there was little overlap between our top ZG genes and those in rodent ZG. In conclusion, (1) the transcriptome profile of human ZG differs from rodent ZG, (2) DACH1 inhibits aldosterone secretion in human adrenals, and (3) transforming growth factor-ß signaling pathway is activated in DACH1 overexpressed cells and may mediate inhibition of aldosterone secretion in human adrenals.


Assuntos
Carcinoma Adrenocortical/genética , Aldosterona/metabolismo , Proteínas do Olho/genética , Regulação Neoplásica da Expressão Gênica , RNA Neoplásico/genética , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/genética , Zona Glomerulosa/metabolismo , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/patologia , Progressão da Doença , Proteínas do Olho/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Fatores de Transcrição/biossíntese , Fator de Crescimento Transformador beta/biossíntese , Células Tumorais Cultivadas , Zona Glomerulosa/patologia
11.
Acta Biomater ; 13: 364-73, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25462841

RESUMO

Microbial redox activity offers a potentially transformative approach to the low-temperature synthesis of nanostructured inorganic materials. Diverse strains of the dissimilatory metal-reducing bacteria Shewanella are known to produce photoactive filamentous arsenic sulfide nanomaterials by reducing arsenate and thiosulfate in anaerobic culture conditions. Here we report in situ microscopic observations and measure the thermally activated (79 kJ mol(-1)) precipitation kinetics of high yield (504 mg per liter of culture, 82% of theoretical maximum) extracellular As2S3 nanofibers produced by Shewanella sp. strain ANA-3, and demonstrate their potential in functional devices by constructing field effect transistors (FETs) based on individual nanofibers. The use of strain ANA-3, which possesses both respiratory and detoxification arsenic reductases, resulted in significantly faster nanofiber synthesis than other strains previously tested, mutants of ANA-3 deficient in arsenic reduction, and when compared to abiotic arsenic sulfide precipitation from As(III) and S(2-). Detailed characterization by electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis and Tauc analysis of UV-vis spectrophotometry showed the biogenic precipitate to consist primarily of amorphous As2S3 nanofibers with an indirect optical band gap of 2.37 eV. X-ray diffraction also revealed the presence of crystalline As8S(9-x) minerals that, until recently, were thought to form only at higher temperatures and under hydrothermal conditions. The nanoscale FETs enabled a detailed characterization of the charge mobility (∼10(-5) cm(2) V(-1) s(-1)) and gating behavior of the heterogeneously doped nanofibers. These studies indicate that the biotransformation of metalloids and chalcogens by bacteria enables fast, efficient, sustainable synthesis of technologically relevant chalcogenides for potential electronic and optoelectronic applications.


Assuntos
Arsenicais/química , Nanofibras/química , Semicondutores , Shewanella/metabolismo , Sulfetos/química , Transistores Eletrônicos , Nanofibras/ultraestrutura , Oxirredução
12.
Nat Genet ; 45(9): 1055-60, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23913004

RESUMO

At least 5% of individuals with hypertension have adrenal aldosterone-producing adenomas (APAs). Gain-of-function mutations in KCNJ5 and apparent loss-of-function mutations in ATP1A1 and ATP2A3 were reported to occur in APAs. We find that KCNJ5 mutations are common in APAs resembling cortisol-secreting cells of the adrenal zona fasciculata but are absent in a subset of APAs resembling the aldosterone-secreting cells of the adrenal zona glomerulosa. We performed exome sequencing of ten zona glomerulosa-like APAs and identified nine with somatic mutations in either ATP1A1, encoding the Na(+)/K(+) ATPase α1 subunit, or CACNA1D, encoding Cav1.3. The ATP1A1 mutations all caused inward leak currents under physiological conditions, and the CACNA1D mutations induced a shift of voltage-dependent gating to more negative voltages, suppressed inactivation or increased currents. Many APAs with these mutations were <1 cm in diameter and had been overlooked on conventional adrenal imaging. Recognition of the distinct genotype and phenotype for this subset of APAs could facilitate diagnosis.


Assuntos
Doenças do Córtex Suprarrenal/genética , Canais de Cálcio Tipo L/genética , Hipertensão/genética , Mutação , ATPase Trocadora de Sódio-Potássio/genética , Doenças do Córtex Suprarrenal/complicações , Doenças do Córtex Suprarrenal/diagnóstico , Substituição de Aminoácidos , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/metabolismo , Análise por Conglomerados , Feminino , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Perfilação da Expressão Gênica , Humanos , Hipertensão/diagnóstico , Hipertensão/etiologia , Masculino , Conformação Proteica , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/metabolismo
13.
Eur J Endocrinol ; 166(6): 993-1002, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22433286

RESUMO

OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is reported to be more common in patients with GH deficiency (GHD) than in the general population. we aimed to determine: i) liver fat in patients with GHD compared with age and body mass index (BMI)-matched controls; and ii) effect of 6 months of GH replacement (GHR) on liver fat. PARTICIPANTS AND METHODS: The study included 28 GHD patients and 24 controls. 12 patients were studied before and after 6 months of GHR. Anthropometry, liver enzymes and lipid profiles were measured, and body composition and intrahepatocellular lipid (IHCL) were determined by magnetic resonance imaging and spectroscopy. RESULTS: Age and BMI (median (inter-quartile range)) of patients and controls were 52.6 (14) vs 52.6 (12) years (P=0.9) and 27.8 (24.7, 34.7) vs 27.9 (25.1, 32.1) kg/m(2) (P=0.9). IGF1 was lower in the patients (11.5 vs 16.0 nmol/l, P=0.002). There was no difference in liver transaminases, lipids or IHCL between patients and controls (2.8 (1.3, 8.6) vs 5.0 (1.5, 12.7), P=0.72), despite significantly higher visceral fat in GHD patients. Thirty-two percent of patients and 50% of controls had NAFLD (defined as IHCL >5.6%), and the relationship between IHCL and BMI was the same in each group. GHR significantly reduced abdominal subcutaneous and visceral fat in all patients; however, GHR did not reduce liver fat. CONCLUSIONS: NAFLD is equally common in patients with GHD and matched controls. GHR is associated with a hierarchical reduction in fat deposition (fat loss: visceral > subcutaneous > liver). Further studies involving GHD patients with NAFLD are required to conclude the role of GHR in treating NAFLD.


Assuntos
Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/deficiência , Gordura Intra-Abdominal , Metabolismo dos Lipídeos , Espectroscopia de Ressonância Magnética , Adulto , Fatores Etários , Idoso , Composição Corporal , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos Transversais , Inglaterra/epidemiologia , Fígado Gorduroso/epidemiologia , Feminino , Hepatócitos/metabolismo , Terapia de Reposição Hormonal/métodos , Humanos , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Prótons , Gordura Subcutânea/metabolismo , Gordura Subcutânea/patologia , Fatores de Tempo
14.
J Pediatr Surg ; 47(2): 303-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22325380

RESUMO

AIM: This study aims to identify new genes not described previously that may be relevant in the etiology or pathophysiology of patients with Hirschsprung disease (HD). This was done by identifying differences in gene expression between normal and abnormal segments of bowel in HD patients compared with controls. METHODS: Full-thickness colonic tissue samples were taken from HD patients, both from the diseased (Ds) and normal segment of the colon (Nr), and from controls (Ct). Samples were further dissected into mucosa (MUC) and muscle (MUS). RNA was extracted and analyzed on Affymetrix Gene Chip Human Gene 1.0 ST arrays. Statistical analyses using ANOVA with a fold change cut off of 2 was applied to detect a number of differentially expressed genes. Selected genes were revalidated by quantitative real-time reverse transcriptase polymerase chain reaction. RESULTS: Thirty-four samples (18 MUS and 16 MUC) were analyzed. MUC (1.64 ± 0.46 µg/mg) and MUS (0.83 ± 0.48 µg/mg) showed good RNA extraction yield and quality. Of the 24,987 filtered on expression genes, MUS showed 220 genes with expression difference of 2-fold, out of which 120 genes were significant with P ≤ .05. Similarly, MUC demonstrated 206 genes with 2-fold changes and 9 had P ≤ .05. Some genes showing differential expression between groups and therefore subject to further analysis were RELN, GAL, GAP43, NRSN1, and GABRG2. CONCLUSION: Analyzed data showed significant differences in expression of above sets of genes with up- and down-regulation, which has not been described before in HD and could have a role in pathogenesis of this condition.


Assuntos
Perfilação da Expressão Gênica , Doença de Hirschsprung/genética , Moléculas de Adesão Celular Neuronais/biossíntese , Moléculas de Adesão Celular Neuronais/genética , Colo/metabolismo , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Feminino , Proteína GAP-43/biossíntese , Proteína GAP-43/genética , Galanina/biossíntese , Galanina/genética , Estudo de Associação Genômica Ampla , Doença de Hirschsprung/metabolismo , Humanos , Lactente , Mucosa Intestinal/metabolismo , Masculino , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Músculo Liso/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de GABA-A/biossíntese , Receptores de GABA-A/genética , Proteína Reelina , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/biossíntese , Serina Endopeptidases/genética
15.
BMC Res Notes ; 5: 27, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22244497

RESUMO

BACKGROUND: With the maturation of next-generation DNA sequencing (NGS) technologies, the throughput of DNA sequencing reads has soared to over 600 gigabases from a single instrument run. General purpose computing on graphics processing units (GPGPU), extracts the computing power from hundreds of parallel stream processors within graphics processing cores and provides a cost-effective and energy efficient alternative to traditional high-performance computing (HPC) clusters. In this article, we describe the implementation of BarraCUDA, a GPGPU sequence alignment software that is based on BWA, to accelerate the alignment of sequencing reads generated by these instruments to a reference DNA sequence. FINDINGS: Using the NVIDIA Compute Unified Device Architecture (CUDA) software development environment, we ported the most computational-intensive alignment component of BWA to GPU to take advantage of the massive parallelism. As a result, BarraCUDA offers a magnitude of performance boost in alignment throughput when compared to a CPU core while delivering the same level of alignment fidelity. The software is also capable of supporting multiple CUDA devices in parallel to further accelerate the alignment throughput. CONCLUSIONS: BarraCUDA is designed to take advantage of the parallelism of GPU to accelerate the alignment of millions of sequencing reads generated by NGS instruments. By doing this, we could, at least in part streamline the current bioinformatics pipeline such that the wider scientific community could benefit from the sequencing technology.BarraCUDA is currently available from http://seqbarracuda.sf.net.

16.
Cardiovasc Res ; 92(1): 29-38, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21632884

RESUMO

AIMS: Peroxisome proliferator-activated receptor-γ coactivators PGC1α and PGC1ß modulate mitochondrial biogenesis and energy homeostasis. The function of these transcriptional coactivators is impaired in obesity, insulin resistance, and type 2 diabetes. We searched for transcriptomic, lipidomic, and electrophysiological alterations in PGC1ß(-/-) hearts potentially associated with increased arrhythmic risk in metabolic diseases. METHODS AND RESULTS: Microarray analysis in mouse PGC1ß(-/-) hearts confirmed down-regulation of genes related to oxidative phosphorylation and the electron transport chain and up-regulation of hypertrophy- and hypoxia-related genes. Lipidomic analysis showed increased levels of the pro-arrhythmic and pro-inflammatory lipid, lysophosphatidylcholine. PGC1ß(-/-) mouse electrocardiograms showed irregular heartbeats and an increased incidence of polymorphic ventricular tachycardia following isoprenaline infusion. Langendorff-perfused PGC1ß(-/-) hearts showed action potential alternans, early after-depolarizations, and ventricular tachycardia. PGC1ß(-/-) ventricular myocytes showed oscillatory resting potentials, action potentials with early and delayed after-depolarizations, and burst firing during sustained current injection. They showed abnormal diastolic Ca(2+) transients, whose amplitude and frequency were increased by isoprenaline, and Ca(2+) currents with negatively shifted inactivation characteristics, with increased window currents despite unaltered levels of CACNA1C RNA transcripts. Inwardly and outward rectifying K(+) currents were all increased. Quantitiative RT-PCR demonstrated increased SCN5A, KCNA5, RYR2, and Ca(2+)-calmodulin dependent protein kinase II expression. CONCLUSION: PGC1ß(-/-) hearts showed a lysophospholipid-induced cardiac lipotoxicity and impaired bioenergetics accompanied by an ion channel remodelling and altered Ca(2+) homeostasis, converging to produce a ventricular arrhythmic phenotype particularly during adrenergic stress. This could contribute to the increased cardiac mortality associated with both metabolic and cardiac disease attributable to lysophospholipid accumulation.


Assuntos
Arritmias Cardíacas/etiologia , Proteínas de Transporte/fisiologia , Potenciais de Ação , Animais , Cálcio/metabolismo , Homeostase , Lisofosfolipídeos/metabolismo , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , Potássio/metabolismo , Proteínas de Ligação a RNA , Transcriptoma
17.
Gastroenterology ; 140(7): 2056-63, 2063.e1, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21396368

RESUMO

BACKGROUND & AIMS: Patients with ferroportin iron overload due to loss-of-function mutations in SLC40A1 have macrophage iron overload, hyperferritinemia, and normal transferrin saturation. In contrast, hepatocellular iron storage, hyperferritinemia, and increased saturation of transferrin are a distinct clinical presentation of ferroportin iron overload that results from SLC40A1 mutations that confer resistance of ferroportin to hepcidin-mediated inactivation. METHODS: SLC40A1 was sequenced in patients from 2 independent pedigrees affected by hepatic iron overload unrelated to HFE. Functions of the ferroportin variants were tested in vitro. RESULTS: A patient heterozygous for the variant p.W158C in SLC40A1 presented with macrophage iron overload, hyperferritinemia, and normal transferrin saturation. A patient with hepatocellular iron storage, hyperferritinemia, and increased transferrin saturation was heterozygous for p.H507R. Expression of the p.W158C form of ferroportin in 293T cells resulted in defective trafficking to the plasma membrane and reduced iron export activity; the iron export activity of cells that expressed the p.H507R form of ferroportin did not differ from cells that expressed ferroportin without this mutation. The p.H507R of ferroportin localizes normally to the plasma membrane but is resistant to hepcidin-mediated inactivation. Addition of a synthetic peptide derived from ferroportin without these mutations (amino acids 500-518) decreased the inhibitory activity of hepcidin in cells, whereas a peptide from the same region, with p.H507R, had no effect on hepcidin activity. CONCLUSIONS: The variant p.W158C in SLC40A1 impairs intracellular trafficking of ferroportin, resulting in reduced iron export. The variant p.H507R does not bind hepcidin in vitro and results in apparent hepcidin resistance.


Assuntos
Proteínas de Transporte de Cátions/genética , Sobrecarga de Ferro/genética , Ferro/metabolismo , Fígado/metabolismo , Mutação , Adulto , Peptídeos Catiônicos Antimicrobianos/metabolismo , Biópsia , Estudos de Casos e Controles , Proteínas de Transporte de Cátions/sangue , Proteínas de Transporte de Cátions/metabolismo , Análise Mutacional de DNA , Ferritinas/metabolismo , Predisposição Genética para Doença , Células HEK293 , Hepcidinas , Humanos , Ferro/sangue , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/metabolismo , Macrófagos/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Transporte Proteico , Transfecção , Transferrina/metabolismo
18.
N Biotechnol ; 28(4): 396-406, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21272674

RESUMO

World population and the need for nutritious food continue to grow. For 14 years farmers from a range of countries across the globe have been accessing transgenic technologies either to reduce crop production costs, increase yield and/or to exploit a range of rotational benefits. In 2009 134 Mha of transgenic crops was grown. The arable area of the EU 27 is approximately 102 Mha; however, only about 0.1 Mha of transgenic crops, mainly maize in Spain, is grown in the EU. This is in part due to limited approvals before the establishment of a moratorium on the cultivation of transgenic crops. In this paper we estimate the revenue foregone by EU farmers, based on the potential hectarages of IR and HT transgenic crops that have been economically successful elsewhere if they were to be grown in areas of the EU where farmers could expect an overall financial benefit. This benefit would accrue primarily from reduced input costs. We estimate that if the areas of transgenic maize, cotton, soya, oil seed rape and sugar beet were to be grown where there is agronomic need or benefit then farmer margins would increase by between €443 and €929 M/year. It is noted that this margin of revenue foregone is likely to increase if the current level of approval and growth remains low, as new transgenic events come to market and are rapidly taken up by farmers in other parts of the world.


Assuntos
Agricultura/economia , Agricultura/legislação & jurisprudência , Produtos Agrícolas/economia , União Europeia/economia , Engenharia Genética/economia , Engenharia Genética/legislação & jurisprudência , Renda , Europa (Continente) , Regulamentação Governamental , Plantas Geneticamente Modificadas
19.
Am J Physiol Gastrointest Liver Physiol ; 300(2): G253-63, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21088234

RESUMO

The inflammasome is a multiprotein complex whose formation is triggered when a NOD-like receptor binds a pathogen ligand, resulting in activated caspase-1, which converts certain interleukins (IL-1ß, IL-18, and IL-33) to their active forms. There is currently no information on regulation of this system around the time of birth. We employed transcript profiling of fetal rat intestinal and lung RNA at embryonic days 16 (E16) and 20 (E20) with out-of-sample validation using quantitative RT-PCR. Transcript profiling and quantitative RT-PCR demonstrated that transcripts of core components of the NOD-like receptor Nlrp6 inflammasome (Nlrp6, Pycard, Caspase-1) and one of its substrates, IL-18, were increased at E20 compared with E16 in fetal intestine and not lung. Immunohistochemistry demonstrated increased Pycard in intestinal epithelium. Western blotting demonstrated that IL-18 was undetectable at E16, clearly detectable at E20 in its inactive form, and detectable postnatally in both its inactive and active form. Dramatic upregulation of IL-18 was also observed in the fetal sheep jejunum in late gestation (P = 0.006). Transcription factor binding analysis of the rat array data revealed an overrepresentation of nuclear transcription factor binding sites peroxisome proliferator-activated receptor γ (PPAR-γ) and retinoid X receptor-α and chicken ovalbumin upstream promoter transcription factor 1 in the region 1,000 bp upstream of the transcription start site. Rosiglitazone, a PPAR-γ agonist, more than doubled levels of NLRP6 mRNA in human intestinal epithelial (Caco2) cells. These observations provide the first evidence, to our knowledge, linking activity of PPAR-γ to expression of a NOD-like receptor and adds to a growing body of evidence linking pattern recognition receptors of the innate immune system and intestinal colonization.


Assuntos
Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário , Inflamassomos/metabolismo , Interleucina-8/metabolismo , Intestinos/embriologia , Pulmão/embriologia , Receptores de Angiotensina/metabolismo , Receptores de Vasopressinas/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Idade Gestacional , Humanos , Imunidade Inata/genética , Imuno-Histoquímica , Inflamassomos/genética , Mucosa Intestinal/embriologia , Análise em Microsséries , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Ratos/embriologia , Ratos Wistar , Receptores de Angiotensina/genética , Receptores de Vasopressinas/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Ovinos/embriologia , Fatores de Transcrição/metabolismo
20.
Plant Biotechnol J ; 9(1): 2-21, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21040386

RESUMO

The concept of sustainable development forms the basis for a wide variety of international and national policy making. World population continues to expand at about 80 M people per year, while the demand for natural resources continues to escalate. Important policies, treaties and goals underpin the notion of sustainable development. In this paper, we discuss and evaluate a range of scientific literature pertaining to the use of transgenic crops in meeting sustainable development goals. It is concluded that a considerable body of evidence has accrued since the first commercial growing of transgenic crops, which suggests that they can contribute in all three traditional pillars of sustainability, i.e. economically, environmentally and socially. Management of herbicide-tolerant and insect-resistant transgenic crops to minimize the risk of weeds and pests developing resistance is discussed, together with the associated concern about the risk of loss of biodiversity. As the world population continues to rise, the evidence reviewed here suggests it would be unwise to ignore transgenic crops as one of the tools that can help meet aspirations for increasingly sustainable global development.


Assuntos
Conservação dos Recursos Naturais , Produtos Agrícolas , Plantas Geneticamente Modificadas , Biodiversidade , Conservação dos Recursos Naturais/economia , Produtos Agrícolas/economia , Economia , Meio Ambiente , Mudança Social
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