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1.
iScience ; 27(4): 109422, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38544568

RESUMO

Discovery of iron-based superconductors paved the way to a competitor of high-temperature superconductors, easier to produce, better performing in high fields, and promising to be less expensive. Critical parameters are investigated by resistivity measurements as a function of temperature, field, and angle R(T,H,θ). This work presents a deep analysis of H-θ phase diagram of PLD-processed Fe(Se,Te) superconducting films, thus revealing material and pinning anisotropy at once. By selecting different thresholds along the R(T,H,θ) curves, all possible regimes emerge. Surprisingly, anisotropy arises moving from the upper critical field toward the irreversibility line: gradually a non-monotonous transition from 3D to 2D, and backward to 3D occurs. Although Fe(Se,Te) appears as a 3D superconductor, its anisotropic pinning landscape shows up similarities with an intrinsic layered superconductor and Fe(Se,Te) definitively mimics YBCO. We propose a general method to disentangle, in any other superconductor, material dimensionality and pinning anisotropy that are key constraints for applications.

2.
Braz J Biol ; 84: e271083, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422281

RESUMO

Cardiovascular disorders, including acute myocardial infarction (AMI), often lead to blood clot formation, impacting blood circulation. Streptokinase, a cost-effective and widely available thrombolytic agent, is crucial in treating thrombosis. This study aimed to produce streptokinase from Streptococcus pyogenes EBL-48 and compare its efficacy with heparin in an animal model. We evaluated the clot-lysing effectiveness of streptokinase produced from Streptococcus pyogenes EBL-48, emphasizing its low cost and ease of production. Streptokinase was produced using pre-optimized fermentation media and purified through ion exchange and gel-filtration chromatography. In vivo analysis involved inducing clots in a trial animal model using ferric chloride, comparing streptokinase with heparin. Ultrasonography assessed the clot-lysing activity of streptokinase. Streptokinase (47 kDa) effectively lysed clots, proving its low cost, easy production, and minimal adverse effects. Ultrasonography confirmed its fibrinolytic efficacy. These findings highlight potential as an affordable and easily produced thrombolytic agent, particularly relevant in resource-limited settings. Streptokinase efficacy and minimal adverse effects make it a promising option for thrombolytic therapy, especially in economically constrained regions. Future studies could optimize production techniques, explore different strains, and conduct clinical trials for human validation. Comparative studies with other thrombolytic agents would enhance understanding of their advantages and limitations.


Assuntos
Fibrinolíticos , Estreptoquinase , Animais , Fermentação , Fibrinolíticos/farmacologia , Fibrinolíticos/uso terapêutico , Heparina , Estreptoquinase/farmacologia , Estreptoquinase/uso terapêutico , Resultado do Tratamento
3.
Prehosp Disaster Med ; 39(1): 37-44, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38047380

RESUMO

INTRODUCTION: Early detection of ST-segment elevation myocardial infarction (STEMI) on the prehospital electrocardiogram (ECG) improves patient outcomes. Current software algorithms optimize sensitivity but have a high false-positive rate. The authors propose an algorithm to improve the specificity of STEMI diagnosis in the prehospital setting. METHODS: A dataset of prehospital ECGs with verified outcomes was used to validate an algorithm to identify true and false-positive software interpretations of STEMI. Four criteria implicated in prior research to differentiate STEMI true positives were applied: heart rate <130, QRS <100, verification of ST-segment elevation, and absence of artifact. The test characteristics were calculated and regression analysis was used to examine the association between the number of criteria included and test characteristics. RESULTS: There were 44,611 cases available. Of these, 1,193 were identified as STEMI by the software interpretation. Applying all four criteria had the highest positive likelihood ratio of 353 (95% CI, 201-595) and specificity of 99.96% (95% CI, 99.93-99.98), but the lowest sensitivity (14%; 95% CI, 11-17) and worst negative likelihood ratio (0.86; 95% CI, 0.84-0.89). There was a strong correlation between increased positive likelihood ratio (r2 = 0.90) and specificity (r2 = 0.85) with increasing number of criteria. CONCLUSIONS: Prehospital ECGs with a high probability of true STEMI can be accurately identified using these four criteria: heart rate <130, QRS <100, verification of ST-segment elevation, and absence of artifact. Applying these criteria to prehospital ECGs with software interpretations of STEMI could decrease false-positive field activations, while also reducing the need to rely on transmission for physician over-read. This can have significant clinical and quality implications for Emergency Medical Services (EMS) systems.


Assuntos
Serviços Médicos de Emergência , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Algoritmos , Software , Eletrocardiografia
4.
Hum Mol Genet ; 32(13): 2192-2204, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37010102

RESUMO

Pathogenic heterozygous variants in SCN2A, which encodes the neuronal sodium channel NaV1.2, cause different types of epilepsy or intellectual disability (ID)/autism without seizures. Previous studies using mouse models or heterologous systems suggest that NaV1.2 channel gain-of-function typically causes epilepsy, whereas loss-of-function leads to ID/autism. How altered channel biophysics translate into patient neurons remains unknown. Here, we investigated iPSC-derived early-stage cortical neurons from ID patients harboring diverse pathogenic SCN2A variants [p.(Leu611Valfs*35); p.(Arg937Cys); p.(Trp1716*)] and compared them with neurons from an epileptic encephalopathy (EE) patient [p.(Glu1803Gly)] and controls. ID neurons consistently expressed lower NaV1.2 protein levels. In neurons with the frameshift variant, NaV1.2 mRNA and protein levels were reduced by ~ 50%, suggesting nonsense-mediated decay and haploinsufficiency. In other ID neurons, only protein levels were reduced implying NaV1.2 instability. Electrophysiological analysis revealed decreased sodium current density and impaired action potential (AP) firing in ID neurons, consistent with reduced NaV1.2 levels. In contrast, epilepsy neurons displayed no change in NaV1.2 levels or sodium current density, but impaired sodium channel inactivation. Single-cell transcriptomics identified dysregulation of distinct molecular pathways including inhibition of oxidative phosphorylation in neurons with SCN2A haploinsufficiency and activation of calcium signaling and neurotransmission in epilepsy neurons. Together, our patient iPSC-derived neurons reveal characteristic sodium channel dysfunction consistent with biophysical changes previously observed in heterologous systems. Additionally, our model links the channel dysfunction in ID to reduced NaV1.2 levels and uncovers impaired AP firing in early-stage neurons. The altered molecular pathways may reflect a homeostatic response to NaV1.2 dysfunction and can guide further investigations.


Assuntos
Epilepsia , Deficiência Intelectual , Epilepsia/genética , Deficiência Intelectual/genética , Canal de Sódio Disparado por Voltagem NAV1.2/genética , Canal de Sódio Disparado por Voltagem NAV1.2/metabolismo , Neurônios/metabolismo , Convulsões , Sódio/metabolismo , Canais de Sódio/genética , Humanos
5.
Braz. j. biol ; 83: e246440, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339395

RESUMO

Abstract Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative's wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.


Resumo A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.


Assuntos
Basidiomycota/genética , Triticum/genética , Doenças das Plantas/genética , Cromossomos de Plantas , Resistência à Doença/genética , Melhoramento Vegetal
6.
Braz. j. biol ; 83: 1-8, 2023. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468950

RESUMO

Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative’s wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.


A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.


Assuntos
Controle de Pragas/economia , Fungos/genética , Fungos/isolamento & purificação , Melhoramento Vegetal/métodos , Triticum/genética
7.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469166

RESUMO

Abstract Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relatives wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.


Resumo A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.

8.
Braz J Biol ; 84: e259729, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35766653

RESUMO

Agro-morphological characterizations offer robust and vigorous means for the precise characterization of germplasm to be used in breeding programs. Here, agro-morphological features-based analyses were considered to figure out the genetic variability within 99 maize accessions and five (5) check varieties including Azam, W. Islamabad, Haq Nawaz, Ev-5 and Evr197. A total of 28 important agro-morphological traits were accounted in the field trails at Hazara University Mansehra Pakistan, during spring 2015. The maximum variation was detected in grain weight per cob (53.43), followed by number of kernels per row (38.64) and flag leaf area (cm2), (38.09%). Cluster analysis divided the 99 maize accession with five check varieties of maize accessions into 7 clusters following the hierarchical clustering. Cluster II recorded 29 genotypes with maximum grain yield per cob, and highest flag leaf length, followed by cluster IV. Lowest grain yield per cob was noted for accessions of cluster I. Similarly, cluster VII consisted of accession with the longest cob length. Moreover, the investigations also revealed that the primary constituent among first five principal components with an eigen value about more than 0.98 in relation to 68.75% of the total variants. PCI accounted for 25.53%, PCII contributed 18.31%, and PCIII is 9.88% of the overall morphological variability were significant contributors were grain weight per cob, number of kernel per row, 1000 grain weight. The identification of a significant level of genetic diversity during the present investigation having implications for maize germplasm characterisation, conservation, and breeding programs aiming at developing improvement maize cultivars.


Assuntos
Intervenção Coronária Percutânea , Zea mays , Humanos , Paquistão , Fenótipo , Melhoramento Vegetal , Zea mays/genética
9.
Braz J Biol ; 83: e246440, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550282

RESUMO

Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative's wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.


Assuntos
Basidiomycota , Triticum , Basidiomycota/genética , Cromossomos de Plantas , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética
11.
J Wound Care ; 26(12): 778-783, 2017 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-29244971

RESUMO

OBJECTIVE: The aim of this study was to evaluate an alternative approach to developing antimicrobial alginate fibres using plant extracts, such as those from neem and papaya leaves. METHOD: Aqueous leaves extract from neem, papaya and their hybrid combinations were used as solvent to develop sodium alginate fibres. Sodium alginate polymer containing these extracts was extruded in a calcium chloride (CaCl2) bath to develop neem (NE), papaya (PE) and their hybrid combinations-based calcium alginate fibres (H-1 to H-5). The surface morphology, spectra, liquid absorption, tensile strength and antimicrobial activity of these developed fibres were measured. RESULTS: NE fibre showed greater tensile strength than PE. The liquid absorption property of all developed fibres decreased, but showed antibacterial properties against Staphylococcus aureus and reduced bacterial growth up to 85% when compared with pure calcium alginate fibre. CONCLUSION: Neem, papaya and hybrid extract-based calcium alginate fibres have the potential to be used as wound dressings.


Assuntos
Anti-Infecciosos/farmacologia , Azadirachta , Bandagens , Materiais Biocompatíveis/farmacologia , Carica , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Ferimentos e Lesões/terapia , Alginatos/farmacologia , Alginatos/ultraestrutura , Microscopia Eletrônica de Varredura , Folhas de Planta , Resistência à Tração
12.
J Wound Care ; 26(3): 115-120, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28277992

RESUMO

OBJECTIVE: The purpose of the study was the development of a suture line that has antibacterial properties and reduces the chance of wound infection thus facilitating the healing process. METHOD: Hydrolysed chitosan, turmeric powder and clove oil were used in different proportions to formulate antimicrobial coating for the polyethylene terephthalate (PET) and polyamide (Nylon 6) threads. The threads were coated using a lab-scale yarn sizing machine. Tensile, and knot strength of the coated sutures were measured. As was the antimicrobial action of Staphylococcus aureus strain ATCC29213. RESULTS: The results show that coatings have slightly improved the tensile and knot strength properties of these sutures. The coated sutures also have satisfactory microbial inhibition against Staphylococcus aureus. CONCLUSION: The coating slightly improved the tensile strength of the sutures. However, the knot is the weakest part of the suture strand. All the formulations of the coating have shown satisfactory antimicrobial activity against Gram-positive Staphylococcus aureus bacteria. We conclude that application of natural coatings on non-absorbable sutures can be useful to reduce the incisions and wound site infections.


Assuntos
Anti-Infecciosos Locais/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Quitosana , Curcuma , Óleos Voláteis , Infecção da Ferida Cirúrgica/prevenção & controle , Materiais Revestidos Biocompatíveis , Humanos , Hidrólise , Suturas , Cicatrização
13.
J Wound Care ; 23(3): 153-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24633061

RESUMO

OBJECTIVE: To assess the feasibility of producing high absorbing, high gelling hybrid fibres made from alginate and psyllium. METHOD: Three methods of psyllium extraction were attempted: the hot, cold and hydrolysed method. The extracted psyllium was sieved before addition to the alginate dope. To assess feasibility, each dope was in turn extruded on a bench-top extruder and then on a pilot-size wet extruder. Calcium chloride solution was used as the coagulation medium for all the extrusions. The produced fibres were subsequently assessed for their linear density, tensile strength, absorption characteristics and swelling behaviour. Optical microscopy was also used to illustrate hybrid fibre swelling behaviour under different conditions RESULTS: This feasibility study has shown that hybrid fibres can be produced when using different methods of psyllium extraction, proving the feasibility of the proposed methodology. However, based on physical and functional assessment of the fibres, it was found that the cold water extraction method leads to better hybrid fibres with superior tensile properties, liquid absorption and swelling, which would render them most suitable for heavily exudating wounds. CONCLUSION: The cold water route is found to be the most effective way of producing polysaccharide-based hybrid fibres. This method is also the least expensive, both in terms of room temperature preparations and functional effectiveness, using only 0.75% psyllium. This fibre is therefore recommended for wound dressing applications. DECLARATION OF INTEREST: There were no external sources of funding for this study. The authors have no conflicts of interest to declare.


Assuntos
Alginatos/farmacologia , Bandagens , Psyllium/farmacologia , Cicatrização , Absorção , Alginatos/química , Cloreto de Cálcio/farmacologia , Estudos de Viabilidade , Géis , Psyllium/química , Resistência à Tração
14.
J Vis Exp ; (83): e51239, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24513575

RESUMO

The longstanding use of Drosophila as a model for cell and developmental biology has yielded an array of tools. Together, these techniques have enabled analysis of cell and developmental biology from a variety of methodological angles. Live imaging is an emerging method for observing dynamic cell processes, such as cell division or cell motility. Having isolated mutations in uncharacterized putative cell cycle proteins it became essential to observe mitosis in situ using live imaging. Most live imaging studies in Drosophila have focused on the embryonic stages that are accessible to manipulation and observation because of their small size and optical clarity. However, in these stages the cell cycle is unusual in that it lacks one or both of the gap phases. By contrast, cells of the pupal wing of Drosophila have a typical cell cycle and undergo a period of rapid mitosis spanning about 20 hr of pupal development. It is easy to identify and isolate pupae of the appropriate stage to catch mitosis in situ. Mounting intact pupae provided the best combination of tractability and durability during imaging, allowing experiments to run for several hours with minimal impact on cell and animal viability. The method allows observation of features as small as, or smaller than, fly chromosomes. Adjustment of microscope settings and the details of mounting, allowed extension of the preparation to visualize membrane dynamics of adjacent cells and fluorescently labeled proteins such as tubulin. This method works for all tested fluorescent proteins and can capture submicron scale features over a variety of time scales. While limited to the outer 20 µm of the pupa with a conventional confocal microscope, this approach to observing protein and cellular dynamics in pupal tissues in vivo may be generally useful in the study of cell and developmental biology in these tissues.


Assuntos
Drosophila melanogaster/embriologia , Drosophila melanogaster/metabolismo , Microscopia Confocal/métodos , Animais , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Feminino , Masculino , Pupa
15.
Carbohydr Polym ; 101: 1184-90, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24299890

RESUMO

Heavily exudating wounds can lead to infection and unnecessary trauma if they are not adequately managed. Manufacturers involved in production and marketing of high absorption silver dressings, besides emphasising high absorptions of their dressings are keen to highlight potent antimicrobial abilities of their products against all kinds of pathogens including MRSA. However, there are little or no credible reports on minimal but potent quantities of silver needed in a dressing to eliminate bacteria spread and growth or how effectively the silver within a dressing is released over time. This paper introduces a new hybrid biomaterial fibre made from polysaccharide-based polymers with inbuilt ability to gel and absorb large quantities of pseudo exudates. Furthermore, it will be reported that the new fibre carries up to six times less silver than it is conventionally used in silver dressings and displays a very slow rate of release whilst maintaining full potency over time against known Gram positive, Gram negative micro-organisms including MRSA. The paper concludes that the developed hybrid fibre has long lasting antimicrobial and gelling properties comparable, if not better, than Acticoat AA and Aquacel Ag, two commercially available silver dressings.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bandagens/microbiologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Cicatrização , Absorção , Alginatos/química , Sequência de Carboidratos , Escherichia coli/efeitos dos fármacos , Géis , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Dados de Sequência Molecular , Psyllium/química , Prata/química
17.
Oncogenesis ; 2: e68, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24018643

RESUMO

Prognosis of head and neck squamous cell carcinoma (HNSCC) is largely determined by the extent of lymph node (LN) metastasis at diagnosis, and this appears to be controlled by cancer cell genetics. To examine the role of these genes in LN metastasis, we created a human-in-mouse orthotopic model of HNSCC and performed comparative microarray analysis of gene expression between populations of HNSCC cell lines derived before and after serial transplantation and in vivo metastasis in mice. Microarray analysis comparing the USC-HN3-GFP, USC-HN3-GFP-G1 and USC-HN3-GFP-G2 cell lines identified overexpression of genes implicated in epithelial-to- mesenchymal transition and the formation of cancer stem cells, including CAV-1, TLR-4 (Toll-like receptor 4), MMP-7 (matrix metalloproteinase 7), ALDH1A3, OCT-4 and TRIM-29. Ingenuity Pathway Analysis confirmed upregulation of respective gene signaling pathways in the USC-HN1-GFP-G2 cell line. Patient HNSCC samples from advanced stages overexpressed ALDH1A3, CAV-1 and MMP-7. Our results show that CAV-1, TLR-4, MMP-7, ALDH1A3, OCT-4 and TRIM-29 have increased expression in HNSCC cells selected for an enhanced metastatic phenotype and suggest that these genes may have an important role in the metastatic potential of HNSCC cells. Inhibition of these genes may therefore have prognostic and therapeutic utility in HNSCC.

18.
Int Urol Nephrol ; 45(5): 1445-52, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23463156

RESUMO

PURPOSE: Measurements of glomerular filtration rate (GFR) are frequently interpreted assuming a linear variation with age. Nonlinear relationships may give a better representation of the changes associated with normal ageing. METHODS: This was a retrospective study of 904 subjects (468 women, 436 men; age range 18-84 years) undergoing assessment as prospective living kidney donors. GFR was evaluated from (51)Cr-EDTA plasma clearance using blood samples taken at 2, 3 and 4 h. The slope-intercept GFR was corrected for body surface area (BSA) using the Haycock formula and for the fast exponential using the Brochner-Mortensen equation. The relationship between age, gender and GFR was examined using best-fit curve analysis. Nonlinear relationships with age were explored using fractional polynomials. RESULTS: There was no gender difference in BSA-corrected GFR over five decades of age (P = 0.40). However, female donors with a body mass index >30 kg/m(2) had a statistically significantly lower GFR than nonobese women (P < 0.01). The best-fit relationship between age and GFR was nonlinear and described using a fractional polynomial model of degree 1 (GFR = 103.9-0.0061 × Age(2) mL/min/1.73 m(2)) with a root mean standard error of 12.9 mL/min/1.73 m(2). The residual variance for this model was significantly smaller than for the best-fit linear model (P = 0.006). CONCLUSIONS: GFR measurements in prospective living kidney donors are best corrected for age using a nonlinear relationship.


Assuntos
Taxa de Filtração Glomerular , Rim/fisiologia , Modelos Estatísticos , Obtenção de Tecidos e Órgãos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Superfície Corporal , Feminino , Humanos , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sexuais , Adulto Jovem
19.
Surg Innov ; 20(3): 282-91, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23355422

RESUMO

INTRODUCTION: Since the first published work on natural orifice translumenal endoscopic surgery (NOTES) a decade ago, progress has been made in the domain of education and training, although questions posed by the original White Paper remain. This article aims to review the current status of education and training in NOTES. METHODS: A review of the literature was conducted to evaluate the following: (1) What are the current training methods/modalities used for NOTES; what is the level of evidence to support their use? (2) How has NOTES clinical training been quantified; what is the evidence relating to performance of different NOTES operators? (3) What clinical NOTES training programs have been established and what are the wider training needs? RESULTS: A total of 25 studies were included: 11 nonanimal studies, 8 animal studies, and 6 descriptions of education programs. Several animal and simulator models demonstrated construct validity, but no study showed human predictive validity. Logarithmic learning curves in animal models demonstrate 10 to 15 cases achieving a proficiency level. Current trends are that gastroenterologists prefer it for diagnostic and basic procedures, whereas surgeons prefer it for complex therapeutic cases. CONCLUSION: The development of a new specialty is intriguing but currently unviable. Training programs have been initiated, but information is limited; the common theme is surgeons receiving endoscopic training. Despite the research done, our knowledge of training and educating in NOTES procedures is limited, preventing a meta-analysis or formal review from being performed. Further research is needed to integrate NOTES into routine clinical procedure.


Assuntos
Cirurgia Endoscópica por Orifício Natural/educação , Animais , Humanos
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