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Resume L’objectif de ce travail etait de comparer les enregistrements electrogoniometriques de la marche d’un groupe temoin de 9 sujets et de 2 groupes de sujets porteurs de protheses totales de genou, conservant ou sacrifiant le ligament croise posterieur (LCP), comportant respectivement 10 et 6 patients. La marche a ete etudiee en terrain plat a 3 vitesses differentes. Nous avons recueilli les angles de flexion-extension du genou et les principaux parametres spatio-temporaux de la marche. La marche s’effectuait de la meme facon avec les protheses conservant ou sacrifiant le LCP, malgre les differences theoriques de cinematique articulaire entre les deux implants. Il existait une modification de la phase d’appui, pendant laquelle l’amplitude de flexion etait liee a la vitesse et etait diminuee dans le groupe des protheses. Cette diminution d’amplitude se repercutait probablement sur la qualite de la marche car elle etait correlee avec une diminution des parametres spatio-temporaux en rapport avec la performance de la marche. Nous avons attribue cette diminution d’amplitude pendant la marche, que la mobilite sans appui ne laissait pas prevoir, par une interaction entre la cinematique articulaire, le systeme musculo-ligamentaire et le schema locomoteur.

TGF-β1 inhibits the cell cycle progression of many types of cells by arresting them in the G1 phase. This cell cycle arrest has been attributed to the regulatory effects of TGF-β1 on both the levels and the activities of the G1 cyclins and their kinase partners. The activities of these kinases are negatively regulated by a number of proteins, such as p15INK4b, p21WAF1/Cip1, and p27Kip1, that physically associate with cyclins, cyclin-dependent kinases (Cdk), or cyclin-Cdk complexes. In epithelial cell lines, TGF-β1 was previously shown to inhibit cell cycle progression through down-regulation of Cdk4 and/or up-regulation of p15INK4b and/or p21WAF1/Cip1. However, TGF-β1 had little or no effect on the p27Kip1 mRNA and protein levels. In this report, we show that, in contrast to observations in epithelial cell lines, TGF-β1 increased the p27Kip1 mRNA and protein levels in the murine B cell lines CH31 and WEHI231. This TGF-β1-mediated induction of p27Kip1 also resulted in an increased association of p27Kip1 with Cdk2 and a decreased Cdk2 kinase activity. In contrast to epithelial cells, however, TGF-β1 had little or no effect on the Cdk4 and p21WAF1/Cip1 protein levels in these B cells. Finally, although several studies suggested a direct role of p53 in TGF-β1-mediated cell cycle arrest in epithelial cells, TGF-β1 inhibited cell cycle progression in CH31 even in the absence of wild-type p53. Taken together, these results suggest that TGF-β1 induces G1 arrest in B cells primarily through a p53-independent up-regulation of p27Kip1 protein.

The thymus is a major site of apoptosis where programmed cell death is involved in the deletion of self-reactive T cells. We have investigated the role of bcl-x in T cells by defining the expression of its two isoforms, bcl-xl and bcl-xs, in a series of human thymocyte cell lines and in human T lymphocytes using the ribonuclease protection assay. Bcl-xl was the predominant isoform expressed in T cell lines and in T lymphocytes, where expression was further enhanced by PMA/ionomycin. This broad expression supports a central role for bcl-x in thymocyte development perhaps through post-transcriptional regulation.

We have investigated the effects of inactivation of localized sites in area 17 on the visual responses of cells in visuotopically corresponding regions of area 18. Experiments were performed on adult normal cats. The striate cortex was inactivated by the injection of nanoliters of lidocaine hydrochloride or of γ-aminobutyric acid (GABA) dissolved in a staining solution. Responses of the simple and complex cells of area 18 to optimally oriented light and dark bars moving in the two directions of motion were recorded before, during, and after the drug injection. Two main effects are described.First, for a substantial number of cells, the drug injection provoked an overall reduction of the cell's visual responses. This nonspecific effect largely predominated in the complex cell family (76% of the units affected). This effect is consistent with the presence of long-range excitatory connections in the visual cortex.Second, the inactivation of area 17 could affect specific receptive-field properties of cells in area 18. The main specific effect was a loss of direction selectivity of a number of cells in area 18, mainly in the simple family (more than 53% of the units affected). The change in direction selectivity comes either from a disinhibitory effect in the nonpreferred direction or from a reduction of response in the preferred direction. It is proposed that the disinhibitory effects were mediated by inhibitory interneurones within area 18. In a very few cases, the change of directional preference was associated with a modification of the cell's response profile.These results showed that the signals from area 17 are necessary to drive a number of units in area 18, and that area 17 can contribute to, or at least modulate, the receptive-field properties of a large number of cells in the parastriate area.

In the field of clinical laboratory medicine, standardization is aimed at increasing the trueness and reliability of measured values. Standardization relies on the use of written standards, reference measurement procedures and reference materials. These are important tools for the design and validation of new tests, and for establishing the metrological traceability of diagnostic assays. Their use supports the translation of research technologies into new diagnostic assays and leads to more rapid advances in science and medicine, as well as improvements in the quality of patient care. The various standardization tools are described, as are the procedures by which written standards, reference procedures and reference materials are developed. Recent efforts to develop standards for use in the field of molecular diagnostics are discussed. The recognition of standardization tools by the FDA and other regulatory authorities is noted as evidence of their important role in ensuring the safety and performance of in vitro diagnostic devices.

We wanted to check whether the differences in joint kinematics between the normal and prosthesis knee, with or without preservation of the posterior cruciate ligament, have an effect on knee flexion-extension during gait and on gait performance.A control group of nine subjects was compared with two groups of subjects with total knee prostheses, with (n = 10 patients) or without (n = 6 patients) preservation of the posterior cruciate ligament. Gait was studied on flat ground at three different walking speeds. We measured the principal temporospatial gait parameters as well as knee flexion and extension angles using continuous electrogoniometry. Non-parametric statistical tests were used to analyze data due to the small number of subjects in each group.The flexion-extension cycles were different between the control group and the prostheses groups, but there was no difference between the two prostheses groups. Measurements made during gait confirmed this result, demonstrating a modification of the temporospatial parameters and a decrease in knee flexion during weight bearing in the prostheses groups compared with the control group. The statistical analysis demonstrated a correlation between these two results.The individual nature of gait parameters hindered data analysis. Indeed, there are many different ways to walk "normally". We were however able to demonstrate the following points. The theoretical differences in joint kinematics between prostheses with or without preservation of the posterior cruciate ligament did not have any effect on gait. There were however significant differences between the control group and the prostheses groups, and these differences depended on walking speed. The most interesting results concerned the changes in the weight-bearing phase. Flexion during this phase was related to walking speed and was decreased in amplitude in both prostheses groups. This lesser amplitude in knee flexion probably affected the quality of gait because it was correlated with decreased temporospatial parameters related to gait performance.This decreased amplitude of flexion during gait, which cannot be expected from motion measurements without weight bearing, can be explained by an interaction between joint kinematics, the musculoligamentary system and the locomotor schema.

We wanted to develop a gait evaluation protocol using an electrogoniometric device allowing simpler measurements than optoelectronic recordings.Gait was studied in a group of nine healthy subjects, mean age 58 years, walking on flat ground at three different speeds. We recorded the knee flexion and extension angles and the main temporospatial gait parameters. The principal conditions required for considering gait to be normal were taken from the literature.The subjects exhibited gait cycles which were normal in 83% of the cases for both knees at all three walking speeds. In 17% of the cases, the subjects walked with a flexed knee or without flexion during the weight-bearing phase. Knee motion was symmetrical between the right and left knee in all subjects. Increased walking speed was associated with increases temporospatial parameters and greater flexion and extension angles, particularly during the weight-bearing phase. There was a correlation between the weight-bearing flexion phase and stride length.The walking distance was moderate but sufficient to avoid the influence of the start and stop cycles. The electrogoniometers were small and did not perturb walking. Certain temporospatial parameters could not be measured directly but could be estimated. We checked that the results corresponded with data in the literature. Lateralization (right, left dominance) did not influence knee movement. Flexion during weight-bearing could influence gait quality by affecting the balance between gravity and quadriceps muscle force, particularly when considering forces used to progress forward. Knee motion varies with walking speed and depends not only on overall knee motion measured without weight bearing, but probably also on the interaction between joint kinematics, the musculoligamentary system, and the locomotor schema.

GATA-1 protein is thought to be a positive regulator of erythroid differentiation. However, ectopic expression of a conditional GATA- 2/estrogen receptor chimera was shown to inhibit erythroid differentiation in a hormone-dependent manner, suggesting the negative regulation of erythroid differentiation by GATA-2 protein. Accordingly, we reasoned that the quantitative balance of GATA-1 and GATA-2 protein might affect erythroid differentiation. In this report, we performed specific and quantitative measurements of GATA-1 and GATA-2 protein in a new erythroid cell line, SAM-1, after treatment with 12-O- tetradecanoylphorbol 13-acetate (TPA). On the basis of these measurements, we show that TPA-induced arrest of erythroid differentiation is coupled with the upregulation of GATA-2 protein, as well as the downregulation of GATA-1 protein. Our results suggest that it is the precise quantitative balance of GATA-1 and GATA-2 protein that regulates erythroid differentiation.

To determine efficiently the clonality of B-cell lymphoproliferative disorders, we modified an immunoglobulin heavy-chain (IGH) gene rearrangement polymerase chain reaction (PCR) assay that requires only a single primer germline variable (VH) and joining (JH) pair and does not involve nested priming, blot hybridization, radioactivity, or sequencing of the amplified PCR product. This simple PCR technique enabled detection of IGH gene rearrangements in as little as 10 pg (one cell equivalent) of DNA or when the clonal-to-polyclonal B-cell ratio was experimentally set at 1:1000. We detected IGH gene rearrangements in 83.5% (71 of 85) of clonal B-cell processes, a sensitivity approaching that of more cumbersome multiple primer and nested primer assays. Moreover, this technique is equally effective with fixed tissues, either B5 or formalin, and can be performed on minute samples, histologic sections, fine-needle aspirates, or cerebrospinal fluids. When compared with conventional Southern blot analysis using a genomic JH probe, the PCR assay demonstrated IGH gene rearrangements in 82% (37 of 45) of B-cell processes positive by Southern blot. No false-positive results were observed in 29 negative control tissues. We now use IGH gene PCR routinely in our laboratory for the detection of clonal B-cells in virtually any tissue sample as an aid in early diagnosis, staging, and monitoring, and the Southern blot procedure is reserved for only a minority of diagnostic cases. for only a minority of diagnostic cases.

The functional relationships between areas 17 and 18 are still incompletely understood; many experiments indicate that cells sharing like properties are linked together, whereas other studies suggest a deviation from this principle. Here we report the effect of using GABA to block circumscribed area 17 neuronal populations with known orientation preferences. We studied the interaction of this treatment on the responses of simple and complex neurons in area 18. The data suggest that these interactions follow different rules for simple and complex cells: specifically, an iso-orientation linkage appears to hold for simple cells while a cross-orientation linkage appears to hold for complex cells.

Every year, millions of individuals visit an emergency department (ED) as result of violence-related injuries. The study objective was to assess the attitudes, perceptions and challenges emergency care providers (ECP) face when caring for victims of violence (VOV). Methods The study was a cross-sectional descriptive survey. ECP completed a web-based 20-item survey including provider demographics, resources, personal experiences and perceptions about caring for VOV. Results 224 ECP participated in the survey. 45.3% were physicians, 34.4% nurses, 12.5% paramedics/EMTs, 6.2% nurse practitioners and 3.1% physician assistants. Participants have a combined professional experience of 2,730 years (mean 12.2). 90.6% of participants practice in an ED setting. Subjects estimate that they care for 484.5 trauma patients/year of which 196 (40.5%) are VOV. 64.1% of ECP characterize violence as an important health issue. 75.4% state their institution has a social service program for intimate partner violence, whereas only 34.4% have one for youth violence and only 31.1% for victims of assault. 65.6% of subjects feel their violence-related social services are suboptimal. Working in an urban center is not associated with availability of social services [p = 0.80 (RR 0.97 95% CI = 0.77 to 1.23)]. 78.1% feel they are negatively affected personally or emotionally when caring for a VOV and 57.1% of participants had been VOV themselves. 59.7% had been previously assaulted by a patient, and 50.8% feel fear when caring for a VOV. Only 62.9% routinely care for the psycho/social needs of VOV. The main barriers to addressing these needs are time (90.3%), education/training (48.4%), and financial (38.7%). Conclusions Interpersonal violence is a serious public health concern. A great number of medical providers have been personally affected by caring for VOV. The psychosocial needs of these patients are not adequately met. Limitations include the potential for self-selection and accuracy of the data. Language: en

This paper presents a summary of the first part of a general research program on the nonlinear theory of composite beams and columns. The paper deals with the experimental study of simply supported composite beams, submitted to uniaxial bending about the major axis. Test results are compared with theoretical results obtained from an elaborate nonlinear analysis.A total of eight composite beams have been tested, four of them with special dowels welded to the wide-flange section web, and steel plates welded at both ends, in order to limit sliding between steel and concrete.By adequately adjusting the concrete stress–strain curve measured on control cylinders, to take into account the effects of strain rate, strain gradient, and steel reinforcement confinement, we obtain a theoretical ultimate bending moment identical to the experimental moment, and a deflection at rupture 10% smaller than the measured one. Key words: reinforced concrete, stress–strain curve, bending, ultimate moment, ultimate deflection, nonlinear theory, composite beams, composite sections.

Subjects were asked to listen to a 3-min. narrative. During Min. 1, 2, or 3 of the narrative, subjects were exposed for 60 sec. to either 5-Hz or 20-Hz electromagnetic fields or to a sham field condition. The fields were generated by commercial devices and applied externally to the side of the head at the level of the temporal lobe. The transcript of each subject's version of the narrative was evaluated by discourse analyses for the numbers of direct recalls or of inferences for each of the three segments. Subjects who had received the 5-Hz fields during Min. 1 and 2 of the narrative displayed twice as many inferences for the material that had been presented during Min. 1 only compared to the 20-Hz groups who did not differ from the sham-field subjects. We hypothesize that there are small alterations in the processing of complex series of verbal stimuli by these weak, theta frequency electromagnetic fields. They might not affect the amount of recall but they may influence the details of recall.