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51.

Introduction

This study aimed to evaluate whether profiles of several soluble mediators in synovial fluid and cartilage tissue are pathology-dependent and how their production is related to in vitro tissue formation by chondrocytes from diseased and healthy tissue.

Methods

Samples were obtained from donors without joint pathology (n = 39), with focal defects (n = 65) and osteoarthritis (n = 61). A multiplex bead assay (Luminex) was performed measuring up to 21 cytokines: Interleukin (IL)-1α, IL-1β, IL-1RA, IL-4, IL-6, IL-6Rα, IL-7, IL-8, IL-10, IL-13, tumor necrosis factor (TNF)α, Interferon (IFN)γ, oncostatin M (OSM), leukemia inhibitory factor (LIF), adiponectin, leptin, monocyte chemotactic factor (MCP)1, RANTES, basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), vascular growth factor (VEGF).

Results

In synovial fluid of patients with cartilage pathology, IL-6, IL-13, IFNγ and OSM levels were higher than in donors without joint pathology (P ≤0.001). IL-13, IFNγ and OSM were also different between donors with cartilage defects and OA (P <0.05). In cartilage tissue from debrided defects, VEGF was higher than in non-pathological or osteoarthritic joints (P ≤0.001). IL-1α, IL-6, TNFα and OSM concentrations (in ng/ml) were markedly higher in cartilage tissue than in synovial fluid (P <0.01). Culture of chondrocytes generally led to a massive induction of most cytokines (P <0.001). Although the release of inflammatory cytokines was also here dependent on the pathological condition (P <0.001) the actual profiles were different from tissue or synovial fluid and between non-expanded and expanded chondrocytes. Cartilage formation was lower by healthy unexpanded chondrocytes than by osteoarthritic or defect chondrocytes.

Conclusions

Several pro-inflammatory, pro-angiogenic and pro-repair cytokines were elevated in joints with symptomatic cartilage defects and/or osteoarthritis, although different cytokines were elevated in synovial fluid compared to tissue or cells. Hence a clear molecular profile was evident dependent on disease status of the joint, which however changed in composition depending on the biological sample analysed. These alterations did not affect in vitro tissue formation with these chondrocytes, as this was at least as effective or even better compared to healthy chondrocytes.  相似文献   
52.
Following 10 daily pairings of multiple conditioned stimuli with injection of cocaine (15 mg/kg), the presentation of the stimuli alone elicited behaviors in rats similar to those induced by cocaine. The behaviors included increased duration or frequency of rearing, sniffing, head bobbing, and horizontal locomotor activity (crossing). The level of the conditioned response for several of these behaviors approximated that induced by the drug itself. The conditioned drug effect showed decay over 15 days but little extinction during 4 daily trials. Brain concentrations of the dopamine metabolites, homovanillic acid and dihydroxyphenylacetic acid, were similar in the conditioned and pseudoconditioned control groups in both the caudate and mesolimbic areas. The behavioral results demonstrate that, in a classical conditioning paradigm, previously neutral stimuli can elicit behaviors similar to those induced by cocaine and that certain conditioned responses show time related decline. This agrees with the reported conditioning of amphetamine's behavioral effects but differs in terms of the action on brain dopamine turnover.  相似文献   
53.
High-throughput sequencing platforms provide an approach for detecting rare HIV-1 variants and documenting more fully quasispecies diversity. We applied this technology to the V3 loop-coding region of env in samples collected from 4 chronically HIV-infected subjects in whom CCR5 antagonist (vicriviroc [VVC]) therapy failed. Between 25,000–140,000 amplified sequences were obtained per sample. Profound baseline V3 loop sequence heterogeneity existed; predicted CXCR4-using populations were identified in a largely CCR5-using population. The V3 loop forms associated with subsequent virologic failure, either through CXCR4 use or the emergence of high-level VVC resistance, were present as minor variants at 0.8–2.8% of baseline samples. Extreme, rapid shifts in population frequencies toward these forms occurred, and deep sequencing provided a detailed view of the rapid evolutionary impact of VVC selection. Greater V3 diversity was observed post-selection. This previously unreported degree of V3 loop sequence diversity has implications for viral pathogenesis, vaccine design, and the optimal use of HIV-1 CCR5 antagonists.  相似文献   
54.
Paced mating induces positive affect as revealed by conditioned place preference (CPP) in female rats. It has been suggested that endogenous opioids are involved in the generation of this positive affect since systemic administration of the opioid antagonist naloxone blocks mating-induced CPP. Several brain structures, including the medial preoptic area (mPOA), the ventromedial nucleus of the hypothalamus (VMH), the amygdala (Me), and the nucleus accumbens (Acb) have been implicated in the control of female sexual behavior. However, it is not known if these structures also participate in the positive affect produced by paced mating. To this end we determined the effects of intracranial administration of naloxone methiodide into the mPOA, VMH, Me and Acb on conditioned place preference induced by paced mating in female rats. Regardless of the site of infusion 5 μg of naloxone did not affect any of the sexual behavior parameters measured during copulation. When CPP was evaluated, the groups infused with naloxone into the mPOA, the VMH, and the Me before each conditioning session did not develop place preference. Only the group infused with naloxone in the Acb and the control groups did so. These results demonstrate that opioid receptors within the mPOA, VMH and Me are necessary for the rewarding aspects of paced mating. We suggest that the Me and VMH are important for the transmission of sensory information produced by copulation while the mPOA is the site where the positive affect is originated.  相似文献   
55.
The kinetics of purple membrane dark adaptation were studied at pH 5 and 7, in the presence and absence of the nonionic detergent Triton X-100. The effect of both sublytic and lytic surfactant concentrations has been considered. Our results show that: (a) dark adaptation is faster at pH 5 than at pH 7, (b) dark adaptation is slower, and of smaller amplitude, in the presence than in the absence of Triton X-100. The data may be interpreted in terms of a simple first-order kinetic model, according to which light-dark adaptation would depend basically on the equilibrium between the 13-cis- and the all-trans-isomers. The experiments also suggest that at pH 5, but not at pH 7, solubilizing surfactant concentrations produce a considerable increase in the velocity of the dark adaptation reaction, perhaps through changes in the microenvironment of a protonable group.  相似文献   
56.
57.
Dynamics of compensation for the deprivations of segregation and discrimination, and the support of multiculturalism derived from ethnic cohesion explain the consumption of out-of-home highbrow leisure events by minority/ethnic individuals, immigrants, and their descendants as efforts toward their integration and assimilation in metropolitan areas. Using data from the Houston Area Survey, I examine whether there are any significant ethnic disparities in the attendance at museums and live theatres, which represent a relevant dimension of out-of-home highbrow leisure in Houston. I found that the odds of frequently attending museums and live theatres are lower for Anglos compared with non-Anglos, and higher for US-born individuals with at least one foreign parent compared with US-born individuals with US-born parents. These findings reveal that the audiences of museums and live theatres in Houston are already characterized by a noteworthy ethnic diversity.  相似文献   
58.
59.
In this work a new strategy for automatic detection of ischemic episodes is proposed. A new measure for ST deviation based on the time–frequency analysis of the ECG and the use of a reduced set of Hermite basis functions for T wave and QRS complex morphology characterization, are the key points of the proposed methodology.Usually, ischemia manifests itself in the ECG signal by ST segment deviation or by QRS complex and T wave changes in morphology. These effects might occur simultaneously. Time–frequency methods are especially adequate for the detection of small transient characteristics hidden in the ECG, such as ST segment alterations. A Wigner–Ville transform-based approach is proposed to estimate the ST shift. To characterize the alterations in the T wave and the QRS morphologies, each cardiac beat is described by expansions in Hermite functions. These demonstrated to be suitable to capture the most relevant morphologic characteristics of the signal. A lead dependent neural network classifier considers, as inputs, the ST segment deviation and the Hermite expansion coefficients. The ability of the proposed method in ischemia episodes detection is evaluated using the European Society of Cardiology ST–T database. A sensitivity of 96.7% and a positive predictivity of 96.2% reveal the capacity of the proposed strategy to perform ischemic episodes identification.  相似文献   
60.
The formulation of the culture medium for a Chinese hamster ovary (CHO) cell line has been investigated in terms of the simultaneous replacement of glucose and glutamine, the most commonly employed carbon and nitrogen sources, pursuing the objective of achieving a more efficient use of these compounds, simultaneously avoiding the accumulation of lactate and ammonium in the medium. The key factor in this process is the selection of compounds that are slowly metabolized. Among the different compounds studied, galactose and glutamate provide the best results, allowing support of cell growth with an optimal balance between nutrient uptake and cell requirements and the generation of minimal quantities of lactate and ammonium. The attained results also highlight the capacity of the cells to redistribute their metabolism as a response to the changes in medium composition.  相似文献   
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