On the functional ordering of biomembranes : Implications for drug binding

Cells are packed with membrane structures, defining the inside and outside, and the different subcellular compartments. These membranes consisting mainly of phospholipids have a variety of functions in addition to providing a permeability barrier for various compounds. These functions involve cellular signaling, where lipids can act as second messengers, or direct regulation of membrane associating proteins. The first part of this study focuses on relating some of the physicochemical properties of membrane lipids to the association of drug compounds to membranes. A fluorescence based method is described allowing for determination of the membrane association of drugs. This method was subsequently applied to a novel drug, siramesine, previously shown to have anti-cancer activity. Siramesine was found to associate with anionic lipids. Especially interesting is its strong affinity for a second messenger lipid phosphatidic acid. This is the first example of a small molecule drug compound specifically interacting with a cellular lipid. Phosphatidic acid in cells is required for the activation of many signaling pathways mediating growth and proliferation. This provides an intriguing possibility for a simple molecular mechanism of the observed anti-cancer activity of siramesine. In the second part the thermal behavior and self assembly of charged and uncharged membrane assemblies was studied. Strong inter-lamellar co-operativity was observed for multilamellar DPPC vesicles using fluorescence techniques together with calorimetry. The commonly used membrane models, large unilamellar vesicles (LUV) and multilamellar vesicles (MLV) were found to possess different biophysical properties as interlamellar interactions of MLVs drive segregation of a pyrene labeled lipid analogue into clusters. The effect of a counter-ion lattice on the self assembly of a cationic gemini surfactant was studied. The presence of NaCl strongly influenced the thermal phase behavior of M-1 vesicles, causing formation of giant vesicles upon exceeding a phase transition temperature, followed by a subsequent transition into a more homogenous dispersion. Understanding the underlying biophysical aspects of cellular membranes is of fundamental importance as the complex picture of the structure and function of cells is evolving. Many of the cellular reactions take place on membranes and membranes are known to regulate the activity of many peripheral and intergral membrane associating proteins. From the point of view of drug design and gene technology, membranes can provide an interesting target for future development of drugs, but also a vehicle sensitive for environmental changes allowing for encapsulating drugs and targeting them to the desired site of action.

TRIM5-CypA融合基因与北平顶猴易感HIV-1的机制研究

天然免疫分子TRIM5α（tripartite motif protein 5α）是近年来发现的一种重要的宿主细胞内逆转录病毒限制因子。在灵长类动物细胞中，TRIM5α蛋白可以在病毒进入细胞后、逆转录前的阶段抑制HIV-1、N-MLV和EIAV等逆转录病毒的复制。由于TRIM5α分子的作用，绝大部分旧大陆猴（Old World monkey）都不能感染HIV-1。而在新大陆猴（New World monkey）中，鹰猴是唯一不感染HIV-1的灵长类动物。研究证明，鹰猴细胞中存在的TRIM5-CypA融合蛋白（owl monkey TRIM5-CypA，omTRIMCyp）介导了抗HIV-1的作用，从而使鹰猴不能感染HIV-1。研究证明，平顶猴是旧大陆猴中唯一报道可以感染HIV-1的灵长类动物，但是其感染HIV-1的机制并不清楚。根据现行的灵长类动物分类学，原属平顶猴群体（M. nemestrina group）的三个亚种分为猕猴属的三个不同种：巽他平顶猴（Sunda pig-tailed macaque，M. nemestrina），北平顶猴（Northern pig-tailed macaque，M. leonina）和明打威猴（Mentawai macaque，M. pagensis）。本论文对中国云南境内北平顶猴TRIM5基因座和感染HIV-1的相关性进行了研究。通过PCR和测序对北平顶猴基因组TRIM5基因座进行分析，发现一个CypA假基因的cDNA通过逆转座机制插入至TRIM5基因座的3’-UTR区域，形成了一个不同于鹰猴TRIM5-CypA的新型融合基因npmTRIMCyp（northern pig-tailed macaque TRIM5-CypA）。通过RT-PCR对npmTRIMCyp融合基因的转录本进行分析，我们鉴定出npmTRIMCyp共有3种不同的选择性剪接产物，分别为npmTRIMCypV1-V3。进一步克隆和测序这3种不同选择性剪接体，通过丰度和序列分析证实：npmTRIMCypV2是优势剪接体，可能在该融合基因产物的功能中发挥作用。研究发现北平顶猴npmTRIMCyp融合基因主要转录本中外显子7和8均被剪切掉。外显子7剪接丢失机制源于TRIM5第6内含子内 3’剪接位点的G/T突变。我们克隆了npmTRIMCyp融合基因cDNA的蛋白编码区ORF，并构建了重组表达npmTRIMCyp的载体，转染HeLa和HeLa-T4细胞并获得稳定表达的细胞株。通过感染HIV-1证实，npmTRIMCyp融合蛋白不能够限制HIV-1的感染和复制，这可能是北平顶猴作为旧大陆猴中唯一对HIV-1易感的灵长类动物的重要分子机制之一。通过HIV-1感染灵长类动物PBMCs实验证实，北平顶猴可以感染HIV-1。npmTRIMCyp可以有效地限制HIV-2ROD的复制，但对SIVmac239只有十分微弱的限制活性。通过构建鹰猴omTRIMCyp和北平顶猴npmTRIMCyp的置换剪接体（SWAP-1和SWAP-2），转染融合基因及其置换剪接体的CRFK细胞激光共聚焦实验证明，npmTRIMCyp、SWAP1和SWAP2在细胞内主要存在于胞浆中。稳定表达融合蛋白和置换剪接体的CRFK细胞感染HIV-1-GFP-VSVG分析表明，含omTRIMCyp外显子7的SWAP-1和SWAP-2均具有限制HIV-1活性，但SWAP-1的活性更强一些，这表明TRIM5结构域的外显子7可能在介导对HIV-1的限制活性中发挥了协同辅助作用。免疫共沉淀研究表明，npmTRIMCyp不能识别和结合HIV-1的衣壳蛋白。对北平顶猴中介导识别逆转录病毒区域的基因组部分进行了测序，共鉴定出46个多态性位点，表明在北平顶猴识别逆转录病毒衣壳区域存在较高的多态性。

FosteraTM PRRS modified live vaccine efficacy against a Canadian heterologous virulent field strain of porcine reproductive and respiratory syndrome virus (PRRSV).

Vaccination is a useful option to control infection with porcine reproductive and respiratory syndrome virus (PRRSV), and several modified live-PRRSV vaccines have been developed. These vaccines have shown some efficacy in reducing the incidence and severity of clinical disease as well as the duration of viremia and virus shedding but have failed to provide sterilizing immunity. The efficacy of modified live-virus (MLV) vaccines is greater against a homologous strain compared with heterologous PRRSV strains. The objective of this study was to evaluate the efficacy of Fostera PRRS MLV vaccine in protecting against challenge with a heterologous field strain widely circulating in the swine herds of eastern Canada. Forty-six piglets were divided into 4 groups: nonvaccinated-nonchallenged; nonvaccinated-challenged; vaccinated-challenged; and vaccinated-nonchallenged. The animals were vaccinated at 23 d of age with Fostera PRRS and challenged 23 d later with a heterologous field strain of PRRSV (FMV12-1425619). Overall, the vaccine showed some beneficial effects in the challenged animals by reducing the severity of clinical signs and the viral load. A significant difference between nonvaccinated and vaccinated animals was detected for some parameters starting 11 to 13 d after challenge, which suggested that the cell-mediated immune response or other delayed responses could be more important than pre-existing PRRSV antibodies in vaccinated animals within the context of protection against heterologous strains.

Deoxynivalenol (DON) naturally contaminated feed impairs the immune response induced by porcine reproductive and respiratory syndrome virus (PRRSV) live attenuated vaccine

Cereal commodities are frequently contaminated with mycotoxins produced by the secondary metabolism of fungal infection. Among these contaminants, deoxynivalenol (DON), also known as vomitoxin, is the most prevalent type B trichothecene mycotoxin worldwide. Pigs are very sensitive to the toxic effects of DON and are frequently exposed to naturally contaminated feed. Recently, DON naturally contaminated feed has been shown to decrease porcine reproductive and respiratory syndrome virus (PRRSV) specific antibody responses following experimental infection. The objective of this study was to determine the impact of DON naturally contaminated feed on the immune response generated following vaccination with PRRSV live attenuated vaccine. Eighteen pigs were randomly divided into three experimental groups of 6 animals based on DON content of the diets (0, 2.5 and 3.5 mg DON/kg). They were fed these rations one week prior to the vaccination and for all the duration of the immune response evaluation. All pigs were vaccinated intra-muscularly with one dose of Ingelvac® PRRSV modified live vaccine (MLV). Blood samples were collected at day −1, 6, 13, 20, 27 and 35 post vaccination (pv) and tested for PRRSV RNA by RT-qPCR and for virus specific antibodies by ELISA. Results showed that ingestion of DON-contaminated diets significantly decreased PRRSV viremia. All pigs fed control diet were viremic while only 1 (17%) and 3 (50%) out of 6 pigs were viremic in the groups receiving 3.5 and 2.5 mg of DON/kg, respectively. Subsequently, all pigs fed control diet developed PRRSV specific antibodies while only viremic pigs that were fed contaminated diets have developed PRRSV specific antibodies. These results suggest that feeding pigs with DON-contaminated diet could inhibit vaccination efficiency of PRRSV MLV by severely impairing viral replication.

Prevalencia de anormalidades estructurales cardiacas en pacientes con enfermedad isquémica. Bogotá 2007 – 2009

Introducción: Las enfermedades cardiovasculares son la causa de muerte más frecuente en el mundo desarrollado, la mayoría de éstas se relacionan con alteraciones de las arterias coronarias, sin embargo un subgrupo de pacientes presentan como causa de isquemia cardiaca alteraciones estructurales. Material y métodos: Estudio Descriptivo. Se utilizó la base de datos recolectada en un servicio de hemodinamia de Bogotá durante dos años. Se aplicaron criterios de inclusión y exclusión y se determinaron cuatro grupos etáreos, a todos los pacientes se les practicó cateterismo cardiaco diagnóstico. Las variables analizadas fueron: diagnóstico de referencia, antecedentes y resultados del cateterismo incluyendo presencia de anomalías estructurales como las valvulopatias, el origen anómalo de las coronarias y los puentes miocárdicos. Para el análisis descriptivo se utilizó reporte de prevalencias y para el análisis de asociaciones se utilizaron tablas de contingencia y el estadístico de prueba Chi cuadrado, no se realizó análisis multivariado debido a que no se encontraron asociaciones estadísticamente significativas. Resultados: La edad promedio de los pacientes fue de 62 años (DS= 10,5), la representación del género masculino fue del 61,7%, la prevalencia de angina estable fue del 61,6%, los 3 antecedentes más prevalentes fueron: hipertensión arterial (41,4%), la hiperlipidemia (19,1%) y la Diabetes Mellitus (17,7%). La prevalencia de las alteraciones estructurales en la población de estudio de manera general fue del 12,9%, y su distribución por tipo fue: 1,4% para puentes miocárdicos, 0,7% para origen anómalo de las arterias coronarias y 10,8% de enfermedad valvular. Conclusiones: Se encontró una asociación entre los antecedentes médicos y la presencia de valvulopatias cardiacas. Se evidenció que el género no tiene relación con la presencia de alteraciones cardíacas a pesar de la mayor participación de hombres en la población de estudio. Las limitantes de este estudio se relacionaron con el tamaño de muestra, debido a la baja prevalencia de las anomalías estructurales medidas.

Desarrollo de la memoria y de la creatividad en el niño de seis a ocho años : estudio piloto en Navarra.

Partiendo de la importancia de las capacidades mnésicas en relación al potencial de aprendizaje y del fomento de la capacidad creadora, poner a punto un tecnicanto de medida adecuado para que los educadores puedan llevar a cabo una exploración de las capacidades mnésicas y creativas de los niños en los tres primeros cursos de EGB. 150 niños de primero, segundo y tercero de EGB de diversos centros de Pamplona en el curso 1984-85. Aplicación piloto del tecnicanto elaborado y uso de la comparación como procedimiento. Proceso: 1. Revisión de los conceptos de memoria y creatividad: bases neurobiológicas y desarrollo. 2. Extracción de la muestra. 3. Aplicación del tecnicanto propuesto y del test de matrices progresivas. 4. Análisis de resultados y conclusiones. Variables intervinientes: A. Memoria lógico-verbal (MLV). B. Memoria visual de imágenes (MVI). C. Creatividad lógico-verbal (CLV). D. Creatividad visualgráfica (CVG). E. Inteligencia general. F. Edad. G. Sexo. 1. La memoria, en sus variedades verbal-lógica y visual significativa, experimenta un incremento cuantitativo y un cambio cualitativo, a lo largo de los tres primeros cursos de EGB. 2. El sexo condiciona, en este período etario, diferencias significativas en cuanto a capacidad mnésica verbal, mostrándose superior, en los varones, por otra parte las niñas tienen mejor uso de estrategias mnemotécnicas lógico-visuales 3. La creatividad lógico-verbal tiene un desarrollo significativo en el período estudiado. No así la creatividad visual-gráfica. De la que parece operar su desarrollo en un período mas pretérito. 4. Dentro de los límites de la inteligencia normal-media, no se constata que el cociente intelectual global influya en el grado de desarrollo de las capacidades mnésicas o creativas. 1. El tecnicanto construido, ha permitido diferenciar cuantitativa y cualitativamente las capacidades mnésicas y creativas de los niños en cada uno de los tres primeros cursos de EGB, y se anuncia como uno de los tecnicantos útiles para el diagnóstico pedagógico. Por su sencillez de aplicación permite al personal docente un planteamiento más adecuado de estrategias educativas para un desarrollo integral. 2. No se pretende delimitar el campo de estudio al período investigado. Posibles investigaciones comparando los intervalos de edad permitirían enriquecer este estudio. 3. Se cuestiona que el desarrollo de la memoria y creatividad deba dejarse a los efectos del azar. La intervención educativa puede incidir favorablemente en su desarrollo.

A block in virus-like particle maturation following assembly of murine leukaemia virus in insect cells

Expression of the murine leukaemia virus (MLV) major Gag antigen p65(Gag) using the baculovirus expression system leads to efficient assembly and release of virus-like particles (VLP) representative of immature MLV. Expression of P180(Gag-Pol), facilitated normally in mammalian cells by readthrough of the p65(Gag) termination codon, also occurs efficiently in insect cells to provide a source of the MLV protease and a pattern of p65(Gag) processing similar to that observed in mammalian cells. VLP release from P180(Gag-Pol) expressing cells however remains essentially immature with disproportionate levels of the uncleaved p65(Gag) precursor when compared to the intracellular Gag profile. Changing the p65(Gag) termination codon altered the level of p65(Gag) and p180(Gag-Pol) within expressing cells but did not alter the pattern of released VLP, which remained immature. Coexpression of p65(Gag) with a fixed readthrough p180(Gag-Pol) also led to only immature VLP release despite high intracellular protease levels. Our data suggest a mechanism that preferentially selects uncleaved p65(Gag) for the assembly of MLV in this heterologous expression system and implies that, in addition to their relative levels, active sorting of the correct p65(Gag) and p180(Gag-Pol) ratios may occur in producer cells. (C) 2003 Elsevier Inc. All rights reserved.

The basis of valuations for secured commercial property lending in the UK

In the context of the financial crash and the commercial property market downturn, this paper examines the basis of valuation used in the UK commercial property lending process. Post-crisis there is discussion of countercyclical measures including the monitoring of asset prices; however there is no consideration of a different approach to property valuation. This paper questions this omission, given the role that valuations play in the bank regulatory process. The different bases of valuation available to lenders within International Valuation Standards are identified as Market Value (MV), Mortgage Lending Value (MLV) and Investment Value (IV), with MV being the most used in the UK. Using the different bases in the period before the financial crisis, the UK property market is modelled at a national office, retail and industrial/warehouse sector level to determine the performance of each alternative valuation basis within the context of counter-cyclical pressures on lending. Both MLV and IV would have produced lower valuations and could have provided lenders with tools for more informed and prudent lending. The paper concludes by recognising some of the practical issues involved in adopting the different bases for the bank lending role but recommends a change to IV.

Intervjustudie av oskyddade trafikanters situation på 13 m mötesseparerad landsväg

I kölvattnet av Nollvisionen uppstår problem för oskyddade trafikanter. Vid mittseparering av 13-metersvägar blir utrymmet för dessa trafikantgrupper otillräckligt och nya lösningar måste till. Detta examensarbete syftar till att förbättra framkomligheten och trafiksäkerheten för oskyddade trafikanter på s k MLV (Mötesseparerad LandsVäg). Målet med examensarbetet har varit att inventera problem, identifiera förbättringsområden, finna bra lösningar samt att beräkna vilka kostnader som dessa lösningar orsakar.Som ett resultat av arbetet har framkommit att det saknas en nationell samstämmighet i synen på hur oskyddade trafikanter på MLV, skall behandlas. Vidare existerar det en stor fokusering i centrala direktiv, kanske mest inofficiella, på bilisters och transportörers behov vid utformningen av MLV. Som en konsekvens av detta har de oskyddade trafikanterna blivit undanträngda, både bildligt och fysiskt talat, från dessa vägtyper och därmed begränsas deras förflyttnings-möjligheter. Ytterligare resultat är att det behövs mer utredning kring hänvisning för de oskyddade trafikanterna på MLV, detta för att i möjligaste mån separera trafikantgrupperna.I arbetet har också utförts en kostnadsberäkning av en GCM-lösning (GCM står för Gång, Cykel och Moped) på en vägsträcka, riksväg 80 mellan Falun och Hofors. Kostnaden blev 1,1 - 2,2 mn kr, vilket motsvarar en projektfördyring med 4,4 - 11 %, beroende på alternativ. De viktigaste slutsatserna i arbetet är att man bör anstränga sig till det yttersta för att erbjuda ett alternativ till en MLV, och att man då också måste förbättra skyltningen, för att undvika att oskyddade trafikanter irrar sig in på MLV:n, trots acceptabla alternativvägar. För detta har ett förslag till ett nytt vägmärke framtagits, Alternativ GCM-väg längs MLV, se Bilaga 5.

Parâmetros do controle postural em mulheres idosas com ou sem histórico de quedas associadas ou não à osteoartrite de joelhos

OBJETIVOS: Comparar parâmetros estabilométricos de mulheres idosas com ou sem histórico de quedas associadas ou não à osteoartrite (OA) de joelhos. MÉTODOS: Cinquenta e seis idosas apresentando ou não histórico de quedas (Q) e OA de joelho unilateral e bilateral foram distribuídas da seguinte maneira: grupo QOA (n = 10), idosas com histórico de queda e OA de joelho; grupo QSOA (n = 11), idosas com histórico de queda e sem OA de joelho; grupo SQOA (n = 14), idosas sem histórico de quedas (SQ) e com OA de joelho; e grupo SQSOA (n = 21), idosas sem histórico de quedas e sem OA de joelho. Para análise do equilíbrio semiestático usando uma plataforma de força, foram avaliados os deslocamentos anteroposterior (DAP) e mediolateral (DML), as velocidades de oscilação anteroposterior (VAP) e mediolateral (VML) em quatro situações na postura ereta. As situações avaliadas foram as seguintes: 1) PFOA: sobre superfície fixa e olhos abertos; 2) PFOF: sobre superfície fixa e olhos fechados; 3) PIOA: sobre superfície instável e olhos abertos; 4) PIOF: sobre superfície instável e os olhos fechados. RESULTADOS: As idosas com OA de joelho apresentaram maior DAP em todas as situações analisadas (P < 0,05), ao passo que idosas com histórico de quedas apresentaram maior DML (P < 0,05). Não houve diferenças entre os grupos para VAP e VML (P > 0,05). CONCLUSÕES: A OA de joelho, por si, é um fator prejudicial no aumento de oscilação do centro de pressão (COP) na direção anteroposterior, enquanto o histórico de quedas, independente da presença de OA de joelhos, traz prejuízos ao controle postural na direção mediolateral.

Avaliação das Sub-Frações dos Carboidratos e das Proteinas, Usando as Metodologias do Cncps e In situ com Bovinos da Raça Nelore. 1. Silagem de Milho

To validate the use of the Cornell Net Carbohydrate and Protein System (CNCPS) under Brazilian conditions, the chemical composition, the potential and the effective degradabilities of the carbohydrate and protein subfractions, and the solid phase passage rate were determined for corn silage in diets with forage:concentrate ratios of 80:20 (DI) and 60:40 (D2) using Nellore cattle. The chromium mordant technique was used to determine the particulate passage rate of solids. For diet 2, there was a reduction in the potentially degradable dry matter (DM), and however not significant, a reduction in the degradation rates of neutral detergent Fiber (NDF, 49%) and neutral detergent insoluble nitrogen (NDIN, 32%), and an increase in the degradation rare of starch (ST, 25%). The use of lag time increased the effective DM degradation (EDDM) of corn silage in both diets (23% and 53% for D1 and D2, respectively). The concentrate ratios did not influence the particulate passage rate of the diets. The higher values related ro the availability of the protein subfractions may indicate a underestimation by CNCPS, Rnd(or) could be attributed to the Zebu animals used in this study.

Avaliação das Sub-Frações dos Carboidratos e das Proteínas, Usando as Metodologias do Cncps e In situ com Bovinos da Raça Nelore. 2. Milho e Farelo de Algodão

The chemical composition of corn and cottonseed meal was determined in accordance with the Cornell Net Carbohydrate and Protein System (CNCPS) in diets with forage:concentrate ratios of 80:20 (D1) and 60:40(D2) using Nellore cattle. The potential and effective degradabilities of the carbohydrate and protein subfractions were also determined. For corn. diet 2 resulted in an increase for potentially degradable dry matter (DM). An increase was observed in the effective degradation of DM (EDDM) when lag time was not considered, however, the use of Eng time increased the EDDM for both diets, 23 and 18% for DI and D2. respectively. For cottonseed meal, diet 2 determined a reduction in the potentially degradable DM: therefore, the use of lag time increased the EDDM for bath diets, 14% for D1 and 15% for D2. The availability of corn starch (fraction B1) was lower than that determined by CNCPS. The higher values for the degradability of corn and cottonseed meal protein subfractions may indicate an underestimation by the model, and, or, could be attributed to the Zebu animals used in this study.

Evaluation of in vitro gas production of roughages and their mixtures using the curves subtraction method

The in vitro gas production of four single roughages and their paired combinations (1:1 on dry matter basis) were evaluated. Two roughage samples (100 mg) per treatment were fermented with ruminal fluid during a 48 h incubation period. Total 48 h gas volumes of fermentation dry matter (DM), neutral detergent fiber (NDF) and soluble compounds in neutral detergent (NDS) were for sugarcane = 16.8, 11.2, 6.9 mL; sugarcane + corn silage = 20.1, 12.6, 9.1 mL; sugarcane + 60-day elephantgrass = 16.5, 17.6 mL; sugarcane + 180-day elephantgrass = 13.8, 8.2, 5.9 mL; corn silage = 18.8, 16.8, 4.7 mL; corn silage + 60-day elephantgrass = 16.3, 15.4, 2.4 mL; corn silage + 180-day elephantgrass = 16.1, 11.8, 4.2 mL; 60-day elephantgrass = 16.9, 19.0 mL and 180-day elephantgrass = fermented 10.7, 12.2 mL, respectively. The NDS gas production was not possible to estimate for sugarcane + 60-day elephantgrass, 60-day elephantgrass and 180-day elephantgrass. The present data shows that the curves subtraction method can be an option to evaluate the contribution of the soluble fractions in roughages to digestion kinetics. However, this method underestimates the NDS gas contribution when roughages are low in crude protein and soluble carbohydrates. It is advisable to directly apply the two-compartmental mathematical model to the digestion curves for roughage DM, when determining the NDS gas volume and the digestion rate. This method is more straightforward and accurate when compared to the curve subtraction method. Non-structural carbohydrates combined with fiber and protein promoted a positive associative effect in sugarcane + corn silage (50:50) mixture. Therefore, it can be concluded that the soluble fraction of roughages greatly contributes to gas production. (C) 2004 Elsevier B.V. All rights reserved.

Postural control parameters in elderly female fallers and non-fallers diagnosed or not with knee osteoarthritis

Objectives: To compare stabilometric parameters of elderly female fallers and non-fallers associated or not with knee osteoarthritis (OA). Methods: Fifty-six elderly female fallers and non-fallers diagnosed or not with unilateral or bilateral knee OA were divided into the following groups: FOA (n = 10), elderly female falters with knee OA; FNOA (n = 11), elderly female fallers without knee OA; NFOA (n = 14), elderly female non-fallers with knee OA; and NFNOA (n = 21), elderly female non-fallers without knee OA. For analyzing semi-static balance on a force platform with the elderly females standing, the following parameters were assessed in four conditions: center of pressure (COP), anterior-posterior and mediolateral displacements (APD and MLD, respectively); and COP anterior-posterior and mediolateral displacement velocities (APV and MLV, respectively). The following conditions were assessed: 1) standing on a firm wooden surface with eyes open (WSEO); 2) standing on a firm wooden surface with eyes closed (WSEC); 3) standing on a foam surface with eyes open (FSEO); 4) standing on a foam surface with eyes closed (FSEC). Results: The elderly females with knee OA showed greater APD in all four conditions assessed (P < 0.05), while the elderly female fallers showed greater MLD (P < 0.05). No difference between the groups was observed for APV and MLV (P > 0.05). Conclusions: Knee OA per se increases APD of the COP, while the history of falls, regardless of the presence of knee OA, hinders postural control in the ML direction.