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1.
Diagn Cytopathol ; 48(12): 1167-1172, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32697040

RESUMO

BACKGROUND: Molecular testing is an essential step in providing patients with advanced non-small-cell lung cancer (NSCLC), the most appropriate front-line targeted therapies. We recently implemented targeted NGS on previously discarded cytology centrifuged supernatant (CCS). METHODS: In this study, we reviewed our implementation process to evaluate its performance. Performance and turnaround time (TAT) of molecular testing on all cytology NSCLC cases submitted for targeted NGS from June 2018 to September 2019 were evaluated, which included 46 and 62 cytology cases before and after implementation of CCS, respectively. Associated cost savings using CCS was also analyzed. RESULTS: The mean TAT defined as the time of collection to time of reporting was 8.5 ± 1.8 days in CCS cohort (range 5-13) as compared with 12.2 ± 5.3 days in the (FFPE) cell block (CB) cohort (range: 6-27). The success rate of sequencing was similar for both cohorts (100% in CCS and 96% in FFPE CB). CONCLUSION: Our results demonstrate that NGS using CCS improves TAT, preserves FFPE CB for other testing, and results in cost savings of $50 per case.


Assuntos
Centrifugação/economia , Centrifugação/métodos , Citodiagnóstico/economia , Citodiagnóstico/métodos , Sequenciamento de Nucleotídeos em Larga Escala/economia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina/métodos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade
2.
Clinics (Sao Paulo) ; 74: e1132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31433042

RESUMO

OBJECTIVE: To describe and analyze a new protocol for the extraction of platelet-rich plasma (PRP) for use in clinical practice and compare this technique with methods that have been previously described in the medical literature. METHODS: We extracted PRP from 20 volunteers using four different protocols (single spin at 1600 ×g, single spin at 600 ×g, double spin at 300 and 700 ×g, and double spin at 600 and 900 ×g). In another group of 12 individuals, we extracted PRP with our new technique (named 'turn down-turn up') consisting of a double spin (200 ×g and 1600 ×g) closed system using standard laboratory equipment (including an ordinary benchtop centrifuge), where the blood remained in the same tube during all processes, reducing the risk of contamination. Platelet counts adjusted to baseline values were compared using analysis of covariance (ANCOVA). RESULTS: Using the four previously described protocols (mentioned above), we obtained concentrations of platelets that were 1.15-, 2.07-, 2.18-, and 3.19-fold greater than the baseline concentration, respectively. With the turn down-turn up technique, we obtained a platelet count that was 4.17-fold (95% confidence interval (CI): 3.09 to 5.25) greater than the baseline platelet count (p=0.063 compared with the double spin at 600 and 900 ×g method). The total cost of the disposable materials used in the extraction process was less than US$10.00 per individual. CONCLUSION: In the present study, we described a simple and safe method for obtaining PRP using low-cost devices.


Assuntos
Centrifugação/métodos , Técnicas de Laboratório Clínico/métodos , Plasma Rico em Plaquetas , Adulto , Centrifugação/economia , Centrifugação/normas , Técnicas de Laboratório Clínico/economia , Técnicas de Laboratório Clínico/normas , Análise Custo-Benefício , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Reprodutibilidade dos Testes , Fatores de Tempo
3.
Clinics ; 74: e1132, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1019702

RESUMO

OBJECTIVE: To describe and analyze a new protocol for the extraction of platelet-rich plasma (PRP) for use in clinical practice and compare this technique with methods that have been previously described in the medical literature. METHODS: We extracted PRP from 20 volunteers using four different protocols (single spin at 1600 ×g, single spin at 600 ×g, double spin at 300 and 700 ×g, and double spin at 600 and 900 ×g). In another group of 12 individuals, we extracted PRP with our new technique (named 'turn down-turn up') consisting of a double spin (200 ×g and 1600 ×g) closed system using standard laboratory equipment (including an ordinary benchtop centrifuge), where the blood remained in the same tube during all processes, reducing the risk of contamination. Platelet counts adjusted to baseline values were compared using analysis of covariance (ANCOVA). RESULTS: Using the four previously described protocols (mentioned above), we obtained concentrations of platelets that were 1.15-, 2.07-, 2.18-, and 3.19-fold greater than the baseline concentration, respectively. With the turn down-turn up technique, we obtained a platelet count that was 4.17-fold (95% confidence interval (CI): 3.09 to 5.25) greater than the baseline platelet count (p=0.063 compared with the double spin at 600 and 900 ×g method). The total cost of the disposable materials used in the extraction process was less than US$10.00 per individual. CONCLUSION: In the present study, we described a simple and safe method for obtaining PRP using low-cost devices.


Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Centrifugação/métodos , Técnicas de Laboratório Clínico/métodos , Plasma Rico em Plaquetas , Contagem de Plaquetas , Fatores de Tempo , Centrifugação/economia , Centrifugação/normas , Reprodutibilidade dos Testes , Análise Custo-Benefício , Técnicas de Laboratório Clínico/economia , Técnicas de Laboratório Clínico/normas
4.
Wounds ; 30(7): 186-190, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30059343

RESUMO

INTRODUCTION: Despite limited clinical evidence, platelet-rich plasma (PRP) is currently used for the treatment of various soft tissue injuries, but optimal use of PRP has yet to be determined. In many instances, PRP is prepared using commercial devices that lack standardized preparation techniques and consistent quality of the PRP produced. OBJECTIVE: The aim of this study is to explore a simple, easy, economical method of PRP preparation that is practical for clinical use. MATERIALS AND METHODS: This cross-sectional study was conducted at the Sports Medicine Clinic at the University of Malaya Medical Centre, Malaysia. Participants were healthy postgraduate students and staff at the Sports Medicine Department. The PRP was prepared using a single centrifugation technique. Leukocyte and platelet levels were compared with that of a whole blood baseline and a commercial preparation kit. RESULTS: The PRP produced using this technique contained significantly higher mean platelet (1725.0 vs. 273.9 x 109/L) and leukocyte (33.6 vs. 7.7 x 109/L) levels compared with whole blood. There was no significant difference in the mean platelet and leukocyte levels between the PRP produced in this study and by a commercial PRP system. CONCLUSIONS: A single-centrifugation protocol using readily available materials in a typical clinical setting could produce PRP of comparable quality to those of a commercial PRP production system.


Assuntos
Centrifugação/métodos , Plasma Rico em Plaquetas , Lesões dos Tecidos Moles/terapia , Medicina Esportiva/economia , Medicina Esportiva/métodos , Adulto , Centrifugação/economia , Análise Custo-Benefício , Estudos Transversais , Feminino , Humanos , Masculino , Lesões dos Tecidos Moles/economia , Adulto Jovem
5.
Aesthet Surg J ; 37(2): 161-168, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27733351

RESUMO

BACKGROUND: Centrifugation (Cf) is a common method of fat processing but may be time consuming, especially when processing large volumes. OBJECTIVES: To determine the effects on fat grafting time, volume efficiency, reoperations, and complication rates of Cf vs an autologous fat processing system (Rv) that incorporates fat harvesting and processing in a single unit. METHODS: We performed a retrospective cohort study of consecutive patients who underwent autologous fat grafting during reconstructive breast surgery with Rv or Cf. Endpoints measured were volume of fat harvested (lipoaspirate) and volume injected after processing, time to complete processing, reoperations, and complications. A budget impact model was used to estimate cost of Rv vs Cf. RESULTS: Ninety-eight patients underwent fat grafting with Rv, and 96 patients received Cf. Mean volumes of lipoaspirate (506.0 vs 126.1 mL) and fat injected (177.3 vs 79.2 mL) were significantly higher (P < .0001) in the Rv vs Cf group, respectively. Mean time to complete fat grafting was significantly shorter in the Rv vs Cf group (34.6 vs 90.1 minutes, respectively; P < .0001). Proportions of patients with nodule and cyst formation and/or who received reoperations were significantly less in the Rv vs Cf group. Based on these outcomes and an assumed per minute operating room cost, an average per patient cost savings of $2,870.08 was estimated with Rv vs Cf. CONCLUSIONS: Compared to Cf, the Rv fat processing system allowed for a larger volume of fat to be processed for injection and decreased operative time in these patients, potentially translating to cost savings. LEVEL OF EVIDENCE 3.


Assuntos
Tecido Adiposo/transplante , Centrifugação/economia , Técnicas Cosméticas/economia , Eficiência Organizacional , Custos de Cuidados de Saúde , Lipectomia/economia , Salas Cirúrgicas/economia , Salas Cirúrgicas/organização & administração , Procedimentos de Cirurgia Plástica/economia , Procedimentos de Cirurgia Plástica/métodos , Coleta de Tecidos e Órgãos/economia , Coleta de Tecidos e Órgãos/métodos , Adulto , Idoso , Orçamentos , Centrifugação/efeitos adversos , Técnicas Cosméticas/efeitos adversos , Redução de Custos , Análise Custo-Benefício , Feminino , Humanos , Lipectomia/efeitos adversos , Pessoa de Meia-Idade , Modelos Econômicos , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/etiologia , Procedimentos de Cirurgia Plástica/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Coleta de Tecidos e Órgãos/efeitos adversos , Transplante Autólogo , Resultado do Tratamento , Fluxo de Trabalho , Adulto Jovem
6.
Vet Clin Pathol ; 45(4): 725-731, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27859449

RESUMO

BACKGROUND: Smears prepared by cytocentrifugation, the so-called cytospins, are widely used in human and veterinary cytology. However, the high cost has hampered the availability of commercial cytospin centrifuges in some veterinary clinics and laboratories. Nevertheless, cytospins are important for evaluating fluids with very low cellularity such as cerebrospinal fluid (CSF) or bronchoalveolar lavage fluid (BALF). OBJECTIVES: The aim of this study was to devise and test the use of a low-cost, in-house manual cytocentrifuge to obtain cytospin preparations. METHODS: Twenty-two fluid samples (including CSF and BALF) were collected from dogs and cats. These were processed in a conventional cytocentrifuge and in an in-house, manual centrifuge (salad spinner). The cytospins obtained by the 2 methods were compared by scoring cellularity, number of cells per field, hemodilution, cell preservation, and proportion of ruptured cells. Additionally, cell number and size were compared by morphometry. Differences between the automated and manual method were statistically assessed. RESULTS: The morphology and cellular detail of cytospin preparations produced by both methods were identical. There was an almost perfect agreement for cellularity, number of cells per HPF, hemodilution and cell preservation (kappa ≥ 0.85), and a moderate agreement for the amount of ruptured cells. Cell recovery was comparable (including in CSF and BALF). CONCLUSIONS: The manual cytocentrifuge produced cytospins with similar cell yield as the automated cytocentrifuge. Considering the low cost and portability, this new method should be particularly useful for cytologic diagnosis in small clinics, developing countries, and in field studies.


Assuntos
Citodiagnóstico/instrumentação , Animais , Líquido da Lavagem Broncoalveolar/citologia , Gatos , Contagem de Células , Centrifugação/economia , Centrifugação/instrumentação , Centrifugação/veterinária , Líquido Cefalorraquidiano/citologia , Citodiagnóstico/economia , Citodiagnóstico/veterinária , Cães
7.
Lab Chip ; 16(2): 377-87, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26675027

RESUMO

This paper presents a simple and cost-effective polyester toner microchip fabricated with laser print and cut lithography (PCL) to use with a battery-powered centrifugal platform for fluid handling. The combination of the PCL microfluidic disc and centrifugal platform: (1) allows parallel aliquoting of two different reagents of four different volumes ranging from nL to µL with an accuracy comparable to a piston-driven air pipette; (2) incorporates a reciprocating mixing unit driven by a surface-tension pump for further dilution of reagents, and (3) is amenable to larger scale integration of assay multiplexing (including all valves and mixers) without substantially increasing fabrication cost and time. For a proof of principle, a 10 min colorimetric assay for the quantitation of the protein level in the human blood plasma samples is demonstrated on chip with a limit of detection of ∼5 mg mL(-1) and coefficient of variance of ∼7%.


Assuntos
Lasers , Técnicas Analíticas Microfluídicas , Poliésteres/química , Impressão , Rotação , Centrifugação/economia , Centrifugação/instrumentação , Colorimetria/economia , Humanos , Técnicas Analíticas Microfluídicas/economia , Técnicas Analíticas Microfluídicas/instrumentação , Impressão/economia , Albumina Sérica/análise , Tensão Superficial
8.
J Vis Exp ; (102): e53052, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26274765

RESUMO

Pumps are mainly used when transferring sterile culture broths in biopharmaceutical and biotechnological production processes. However, during the pumping process shear forces occur which can lead to qualitative and/or quantitative product loss. To calculate the mechanical stress with limited experimental expense, an oil-water emulsion system was used, whose suitability was demonstrated for drop size detections in bioreactors(1). As drop breakup of the oil-water emulsion system is a function of mechanical stress, drop sizes need to be counted over the experimental time of shear stress investigations. In previous studies, the inline endoscopy has been shown to be an accurate and reliable measurement technique for drop size detections in liquid/liquid dispersions. The aim of this protocol is to show the suitability of the inline endoscopy technique for drop size measurements in pumping processes. In order to express the drop size, the Sauter mean diameter d32 was used as the representative diameter of drops in the oil-water emulsion. The results showed low variation in the Sauter mean diameters, which were quantified by standard deviations of below 15%, indicating the reliability of the measurement technique.


Assuntos
Centrifugação/instrumentação , Endoscopia/instrumentação , Centrifugação/economia , Análise Custo-Benefício , Emulsões , Endoscopia/economia , Resistência ao Cisalhamento
9.
J Biomed Mater Res A ; 103(12): 3825-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26097136

RESUMO

Three-dimensional (3D) tissues can be reconstructed by cell sheet technology, and various clinical researches using these constructed tissues have already been initiated to regenerate damaged tissues. While 3D tissues can be easily fabricated by layering cell sheets, the attachment period for cell adhesion between a cell sheet and a culture dish, or double-layered cell sheets normally takes 20-30 min. This study proposed a more rapid fabrication system for bioengineered tissue using cell sheet technology and centrifugation. A C2C12 mouse myoblast sheet harvested from a temperature-responsive culture dish will attach tightly to a culture dish or another cell sheet at 37°C after a 20 min-incubation. However, the same cell sheet centrifuged (12-34 × g) for 3 min also attached tightly to a dish or another cell sheet at 37°C after only a 3 min-incubation. The manipulation time was reduced by approximately two-thirds by centrifugation. The rapid attachments were also cross-sectionally confirmed by optical coherence tomography. These rapidly constructed cell sheet-tissues using centrifugation showed active cell metabolism, cell viability, and very high production of vascular endothelial growth factor, like those prepared by the conventional method; indicating complete cell sheet-attachment without any cell damage. This new system will be a powerful tool in the fields of cell sheet-based tissue engineering and regenerative medicine, and accelerate the use of cell sheets in clinical applications.


Assuntos
Centrifugação/instrumentação , Mioblastos/citologia , Engenharia Tecidual/instrumentação , Animais , Adesão Celular , Linhagem Celular , Sobrevivência Celular , Centrifugação/economia , Desenho de Equipamento , Camundongos , Mioblastos/metabolismo , Poliestirenos/química , Engenharia Tecidual/economia
10.
Lab Chip ; 14(9): 1527-37, 2014 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-24590165

RESUMO

Assay automation is the key for successful transformation of modern biotechnology into routine workflows. Yet, it requires considerable investment in processing devices and auxiliary infrastructure, which is not cost-efficient for laboratories with low or medium sample throughput or point-of-care testing. To close this gap, we present the LabTube platform, which is based on assay specific disposable cartridges for processing in laboratory centrifuges. LabTube cartridges comprise interfaces for sample loading and downstream applications and fluidic unit operations for release of prestored reagents, mixing, and solid phase extraction. Process control is achieved by a centrifugally-actuated ballpen mechanism. To demonstrate the workflow and functionality of the LabTube platform, we show two LabTube automated sample preparation assays from laboratory routines: DNA extractions from whole blood and purification of His-tagged proteins. Equal DNA and protein yields were observed compared to manual reference runs, while LabTube automation could significantly reduce the hands-on-time to one minute per extraction.


Assuntos
Centrifugação/instrumentação , Laboratórios , Técnicas Analíticas Microfluídicas/instrumentação , Automação , Centrifugação/economia , Análise Custo-Benefício , DNA/sangue , DNA/isolamento & purificação , Humanos , Técnicas Analíticas Microfluídicas/economia
11.
J Lab Autom ; 19(3): 285-96, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24056858

RESUMO

In medical diagnostics, detection of cells exhibiting specific phenotypes constitutes a paramount challenge. Detection technology must ensure efficient isolation of (often rare) targets while eliminating nontarget background cells. Technologies exist for such investigations, but many require high levels of expertise, expense, and multistep protocols. Increasing automation, miniaturization, and availability of such technologies is an aim of microfluidic lab-on-a-chip strategies. To this end, we present an integrated, dual-force cellular separation strategy using centrifugo-magnetophoresis. Whole blood spiked with target cells is incubated with (super-)paramagnetic microparticles that specifically bind phenotypic markers on target cells. Under rotation, all cells sediment into a chamber located opposite a co-rotating magnet. Unbound cells follow the radial vector, but under the additional attraction of the lateral magnetic field, bead-bound target cells are deflected to a designated reservoir. This multiforce separation is continuous and low loss. We demonstrate separation efficiently up to 92% for cells expressing the HIV/AIDS relevant epitope (CD4) from whole blood. Such highly selective separation systems may be deployed for accurate diagnostic cell isolations from biological samples such as blood. Furthermore, this high efficiency is delivered in a cheap and simple device, thus making it an attractive option for future deployment in resource-limited settings.


Assuntos
Automação Laboratorial/instrumentação , Linfócitos T CD4-Positivos/citologia , Separação Imunomagnética/instrumentação , Dispositivos Lab-On-A-Chip , Microfluídica/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/economia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/patologia , Automação Laboratorial/economia , Buffy Coat/citologia , Buffy Coat/imunologia , Buffy Coat/metabolismo , Buffy Coat/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Centrifugação/economia , Centrifugação/instrumentação , Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Infecções por HIV/diagnóstico , Infecções por HIV/economia , Infecções por HIV/imunologia , Infecções por HIV/patologia , Células HL-60 , Células HeLa , Custos de Cuidados de Saúde , Humanos , Separação Imunomagnética/economia , Dispositivos Lab-On-A-Chip/economia , Microfluídica/economia , Microesferas , Sistemas Automatizados de Assistência Junto ao Leito/economia , Testes Imediatos/economia , Estudo de Prova de Conceito , Espectrometria de Fluorescência/economia , Espectrometria de Fluorescência/instrumentação
12.
Biotechnol Prog ; 29(5): 1239-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23847160

RESUMO

The bioreactor volume delineating the selection of primary clarification technology is not always easily defined. Development of a commercial scale process for the manufacture of therapeutic proteins requires scale-up from a few liters to thousands of liters. While the separation techniques used for protein purification are largely conserved across scales, the separation techniques for primary cell culture clarification vary with scale. Process models were developed to compare monoclonal antibody production costs using two cell culture clarification technologies. One process model was created for cell culture clarification by disc stack centrifugation with depth filtration. A second process model was created for clarification by multi-stage depth filtration. Analyses were performed to examine the influence of bioreactor volume, product titer, depth filter capacity, and facility utilization on overall operating costs. At bioreactor volumes <1,000 L, clarification using multi-stage depth filtration offers cost savings compared to clarification using centrifugation. For bioreactor volumes >5,000 L, clarification using centrifugation followed by depth filtration offers significant cost savings. For bioreactor volumes of ∼ 2,000 L, clarification costs are similar between depth filtration and centrifugation. At this scale, factors including facility utilization, available capital, ease of process development, implementation timelines, and process performance characterization play an important role in clarification technology selection. In the case study presented, a multi-product facility selected multi-stage depth filtration for cell culture clarification at the 500 and 2,000 L scales of operation. Facility implementation timelines, process development activities, equipment commissioning and validation, scale-up effects, and process robustness are examined.


Assuntos
Custos e Análise de Custo/economia , Cultura Primária de Células/economia , Animais , Anticorpos Monoclonais/metabolismo , Reatores Biológicos/economia , Células CHO , Centrifugação/economia , Centrifugação/métodos , Cromatografia de Afinidade/economia , Cromatografia de Afinidade/métodos , Simulação por Computador , Cricetulus , Filtração/economia , Filtração/métodos , Modelos Teóricos , Cultura Primária de Células/métodos , Software
13.
Bioresour Technol ; 128: 241-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23196245

RESUMO

Inefficient or energy-intensive microalgal harvesting strategies for biodiesel production have been a major setback in the microalgae industry. Harvesting by centrifugation is generally characterized by high capture efficiency (>90%) under low flow rates and high energy consumption. However, results from the present study demonstrated that by increasing the flow rates (>1L/min), the lower capture efficiencies (<90%) can be offset by the larger volumes of culture water processed through the centrifuge, resulting in net lower energy consumption. Energy consumption was reduced by 82% when only 28.5% of the incoming algal biomass was harvested at a rate of 18 L/min by centrifugation. Harvesting algal species with a high lipid content and high culture density could see harvesting costs of $0.864/L oil using the low efficiency/high flow rate centrifugation strategy as opposed to $4.52/L oil using numbers provided by the Department of Energy for centrifugation harvesting.


Assuntos
Biocombustíveis/economia , Biocombustíveis/microbiologia , Separação Celular/economia , Separação Celular/instrumentação , Centrifugação/economia , Centrifugação/instrumentação , Microalgas/isolamento & purificação , Análise Custo-Benefício , Estados Unidos
14.
Biotechniques ; 53(2): 104-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23030063

RESUMO

When separating two species with similar densities but differing sedimentation velocities (because of differences in size), centrifugal elutriation is generally the method of choice. However, a major drawback to this approach is the requirement for specialized equipment. Here, we present a new method that achieves similar separations using standard benchtop centrifuges by loading the seperands as a layer on top of a dense buffer of a specified length, and running the benchtop centrifugation process for a calculated amount of time, thereby ensuring that all faster moving species are collected at the bottom, while all slower moving species remain in the buffer. We demonstrate the use of our procedure to isolate bacteria from blood culture broth (a mixture of bacterial growth media, blood, and bacteria).


Assuntos
Bactérias/isolamento & purificação , Células Sanguíneas/citologia , Separação Celular/métodos , Centrifugação/métodos , Algoritmos , Soluções Tampão , Separação Celular/economia , Separação Celular/instrumentação , Centrifugação/economia , Centrifugação/instrumentação , Eritrócitos/citologia , Humanos , Cinética
15.
Rev. cuba. farm ; 46(1)ene.-mar. 2012.
Artigo em Espanhol | CUMED | ID: cum-51129

RESUMO

Introducción: la separación centrífuga es muy utilizada para la obtención de productos farmacéuticos y biotecnológicos. Es la separación o concentración de fosfolípidos o ambas una de estas aplicaciones. Objetivo: seleccionar y evaluar el uso de diferentes separadores centrífugos así como el establecimiento de sus condiciones de operación, para la obtención de un concentrado de una mezcla fosfolipídica típica. Métodos: se realizó la caracterización física de la suspensión a tratar para seleccionar el tipo de centrífuga más adecuada y se determinaron las condiciones de operación de esta. Se evaluó además la composición de las mezclas fosfolípidicas obtenidas en cada caso. Resultados: se obtuvo que tanto una centrifuga de discos como una tubular son competentes para lograr la concentración de fosfolípidos, con una composición que puede ser utilizada para la formulación de liposomas, cosméticos y medicamentos. Conclusiones: Teniendo en cuenta la competencia de ambas centrífugas para rendir una mezcla fosfolipídica específica y los similares rendimientos en la separación, la mejor elección es una centrífuga tubular vertical por ser más económica y sencilla en su operación que la de discos.(AU)


Introduction: centrifuge separation is very useful for obtaining pharmaceutical and biotechnological products. One of these applications is the separation and/or concentration of phospholipids. Objective: to evaluate the use of different centrifuge separators, as well as the establishment of their operation conditions in order to obtain a typical phospholipidic mixture concentrate. Methods: a physical characterization of the suspension to be treated was made for selecting the most adequate kind of centrifuge and its operational conditions were determined. The composition of the phospholipidic mixtures in every case was also evaluated Results: both the disk and the tubular centrifuges turned to be fit for reaching the phospholipids concentration; hence the composition can be used for the formulation of liposomes, cosmetics and drugs. Conclusions: Given the adequacy of both centrifuges for reaching a specific phospholipidic mixture and their similar performances in the separation process, the best choice will be the vertical tubular centrifuge since it is less expensive and simpler in operation than the disk centrifuge.(AU)


Assuntos
Fosfolipídeos , Centrifugação , Centrifugação/economia
16.
Rev. cuba. farm ; 46(1): 4-10, ene.-mar. 2012.
Artigo em Espanhol | LILACS | ID: lil-628438

RESUMO

Introducción: la separación centrífuga es muy utilizada para la obtención de productos farmacéuticos y biotecnológicos. Es la separación o concentración de fosfolípidos o ambas una de estas aplicaciones. Objetivo: seleccionar y evaluar el uso de diferentes separadores centrífugos así como el establecimiento de sus condiciones de operación, para la obtención de un concentrado de una mezcla fosfolipídica típica. Métodos: se realizó la caracterización física de la suspensión a tratar para seleccionar el tipo de centrífuga más adecuada y se determinaron las condiciones de operación de esta. Se evaluó además la composición de las mezclas fosfolípidicas obtenidas en cada caso. Resultados: se obtuvo que tanto una centrifuga de discos como una tubular son competentes para lograr la concentración de fosfolípidos, con una composición que puede ser utilizada para la formulación de liposomas, cosméticos y medicamentos. Conclusiones: Teniendo en cuenta la competencia de ambas centrífugas para rendir una mezcla fosfolipídica específica y los similares rendimientos en la separación, la mejor elección es una centrífuga tubular vertical por ser más económica y sencilla en su operación que la de discos.


Introduction: centrifuge separation is very useful for obtaining pharmaceutical and biotechnological products. One of these applications is the separation and/or concentration of phospholipids. Objective: to evaluate the use of different centrifuge separators, as well as the establishment of their operation conditions in order to obtain a typical phospholipidic mixture concentrate. Methods: a physical characterization of the suspension to be treated was made for selecting the most adequate kind of centrifuge and its operational conditions were determined. The composition of the phospholipidic mixtures in every case was also evaluated Results: both the disk and the tubular centrifuges turned to be fit for reaching the phospholipids concentration; hence the composition can be used for the formulation of liposomes, cosmetics and drugs. Conclusions: Given the adequacy of both centrifuges for reaching a specific phospholipidic mixture and their similar performances in the separation process, the best choice will be the vertical tubular centrifuge since it is less expensive and simpler in operation than the disk centrifuge.


Assuntos
Centrifugação/economia , Centrifugação , Fosfolipídeos
17.
Reprod Domest Anim ; 46 Suppl 2: 18-22, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21884271

RESUMO

Colloid centrifugation of boar semen has been reported sporadically for at least the last two decades, beginning with density gradient centrifugation (DGC) and progressing more recently to single layer centrifugation (SLC). Single layer centrifugation through a species-specific colloid has been shown to be effective in selecting the best spermatozoa (spermatozoa with good motility and normal morphology) from boar sperm samples. The method is easier to use and less time-consuming than DGC and has been scaled-up to allow whole ejaculates from other species, e.g. stallions, to be processed in a practical manner. The SLC technique is described, and various scale-up versions are presented. The potential applications for SLC in boar semen preservation are as follows: to improve sperm quality in artificial insemination (AI) doses for 'problem' boars; to increase the shelf-life of normal stored sperm samples, either by processing the fresh semen before preparing AI doses or by processing the stored semen dose to extract the best spermatozoa; to remove pathogens (viruses, bacteria), thus improving biosecurity of semen doses and potentially reducing the use of antibiotics; to improve cryosurvival by removing dead and dying spermatozoa prior to cryopreservation; to select spermatozoa for in vitro fertilization. These applications are discussed and practical examples are provided. Finally, a few thoughts about the economic value of the technique to the boar semen industry are presented.


Assuntos
Centrifugação/veterinária , Coloides , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Suínos/fisiologia , Animais , Centrifugação/economia , Inseminação Artificial/veterinária , Masculino , Preservação do Sêmen/economia , Preservação do Sêmen/métodos
18.
Am J Trop Med Hyg ; 85(2): 327-32, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21813855

RESUMO

This report describes the development of a hand-powered centrifuge to determine hematocrit values in low-resource settings. A hand-powered centrifuge was constructed by using a salad spinner. Hematocrit values were measured by using the hand-powered device, and results were compared with those of a benchtop centrifuge. The packed cell volume (PCV) measured with the hand-powered device correlated linearly with results obtained with a benchtop centrifuge (r = 0.986, P < 0.001). The PCVs measured with the hand-powered centrifuge were consistently 1.14 times higher than those measured with the benchtop system. The 14% increase in PCV measured with the hand-powered centrifuge is caused by increased plasma trapped in the cell column. The reader card was adjusted to compensate for trapped plasma. A hand-powered centrifuge and calibrated reader card can be constructed for U.S. $35 and can accurately determine hematocrit values. It is suitable for use in low-resource settings because it is mechanically-powered, inexpensive, and accurate.


Assuntos
Anemia/diagnóstico , Centrifugação/economia , Centrifugação/instrumentação , Desenho de Equipamento , Recursos em Saúde , Hematócrito , Humanos , Pobreza
19.
Anim Reprod Sci ; 124(1-2): 85-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21367542

RESUMO

For many years in human assisted-reproduction procedures there have been special protocols to prepare and improve sperm quality. Colloidal centrifugation (CC) is a useful technique that has been proved to enhance semen quality by selection of the best spermatozoa for different species. Its use is recommended to improve fertility of subfertile stallions but current CC protocols are clinically complicated in the equine sperm processing technique due to economic and technical difficulties. The aim of this study was to determine the optimal processing procedures to adapt the use of a CC product (EquiPure™) in the equine reproduction industry. A total of nineteen ejaculates were collected from 10 Purebred Spanish Horses (P.R.E horses) using a Missouri artificial vagina. Gel-free semen aliquots were analyzed prior to treatment (control). Semen was subjected to one of six CC protocols with EquiPure™ and centrifuged samples were statistically evaluated by ANOVA and Duncan tests (p<0.05) for sperm quality and recovery rate. We obtained higher values by colloidal centrifugation in LIN, STR and BCF variables and DNA fragmentation index trended to be lower in most of the CC protocols. The studied protocols were shown to be as efficient in improving equine sperm quality as the current commercial EquiPure™, with the added advantage of being much more economical and simple to use. According to these results it seems to be possible to incorporate single layer and or high colloidal centrifugation volume protocols what would make them simple, economic and clinically viable for the equine sperm processing procedure.


Assuntos
Protocolos Clínicos , Cavalos , Análise do Sêmen/veterinária , Manejo de Espécimes/veterinária , Animais , Centrifugação/economia , Centrifugação/métodos , Centrifugação/veterinária , Masculino , Análise do Sêmen/métodos , Manejo de Espécimes/métodos , Recuperação Espermática/veterinária
20.
Biophys J ; 98(11): L53-5, 2010 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-20513382

RESUMO

Precise manipulation of single molecules has already led to remarkable insights in physics, chemistry, biology, and medicine. However, widespread adoption of single-molecule techniques has been impeded by equipment cost and the laborious nature of making measurements one molecule at a time. We have solved these issues by developing an approach that enables massively parallel single-molecule force measurements using centrifugal force. This approach is realized in an instrument that we call the centrifuge force microscope in which objects in an orbiting sample are subjected to a calibration-free, macroscopically uniform force-field while their micro-to-nanoscopic motions are observed. We demonstrate high-throughput single-molecule force spectroscopy with this technique by performing thousands of rupture experiments in parallel, characterizing force-dependent unbinding kinetics of an antibody-antigen pair in minutes rather than days. Additionally, we verify the force accuracy of the instrument by measuring the well-established DNA overstretching transition at 66 +/- 3 pN. With significant benefits in efficiency, cost, simplicity, and versatility, single-molecule centrifugation has the potential to expand single-molecule experimentation to a wider range of researchers and experimental systems.


Assuntos
Centrifugação/métodos , Microscopia/métodos , Análise Espectral/métodos , Anticorpos/química , Centrifugação/economia , Centrifugação/instrumentação , DNA/química , Digoxigenina/química , Desenho de Equipamento , Cinética , Microscopia/economia , Microscopia/instrumentação , Conformação de Ácido Nucleico , Pinças Ópticas , Análise Espectral/economia , Análise Espectral/instrumentação
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