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The predictive value of the leveling off of within session performance for procedural memory consolidation.

In addition to performance gains accrued concurrently with a given training experience (within-session gains) robust, delayed (between-session) performance gains may slowly evolve in the absence of any additional practice in a variety of tasks. The latter is regarded as a behavioral manifestation of skill memory consolidation. It is not known, however, how much practice is necessary for the triggering of these consolidation effects. Here, using an enumeration task, we show that the triggering of delayed gains could be robustly predicted from each individual's performance curve. Delayed performance gains evolved consistently only when practice continued to the point at which within-session performance leveled off (saturation). No delayed gains were found when training was stopped before this individually determined point. Our results support the notion that the triggering of consolidation processes depends on the saturation of a distinct, early phase of learning rather than on the absolute number of task repetitions, and suggest the possibility that training and rehabilitation protocols could be optimized on an individual basis.

Adult↗

Performance of a molecular viability assay for the diagnosis of Pneumocystis pneumonia in HIV-infected patients.

Pneumocystis pneumonia (PCP), caused by infection with Pneumocystis jirovecii, remains an important opportunistic infection in humans. A reverse transcriptase polymerase chain reaction assay has been shown to specifically detect viable P. jirovecii organisms. In the current study, we evaluated this assay on different types of respiratory samples. The assay had a diagnostic sensitivity of 100% and a specificity of 86% when applied to bronchoalveolar lavage samples. The assay's performance declined when applied to less invasive induced sputum and oropharyngeal wash (OPW) samples. The sensitivity, when applied to OPWs, was improved by examining multiple sequential OPW samples and was affected by clinical sampling parameters that could increase or decrease the number of potential organisms in the oropharynx. When used in conjunction with an optimized clinical sampling protocol, this assay may become a useful tool for detecting and monitoring P. jirovecii in minimally invasive clinical samples.

AIDS-Related Opportunistic Infections↗

Quantitative echocardiographic evaluation of myocardial perfusion using interrupted contrast infusion technique: in vivo validation studies and feasibility in human beings.

BACKGROUND: We recently developed a new approach for contrast echocardiographic quantification of myocardial perfusion, based on brief interruptions of contrast infusion, which was designed to overcome the limitations of existing techniques. In this study, our technique was initially validated in a series of animal experiments designed to detect regional perfusion variations in vivo. Subsequently, clinical feasibility of perfusion measurements was tested. METHODS: Regional perfusion was measured transthoracically in 6 anesthetized pigs during baseline, partial left anterior descending coronary artery occlusion, and reperfusion, and validated with fluorescent microspheres. Adenosine-induced changes in perfusion were measured in 8 healthy volunteers. In both protocols, imaging was optimized during contrast infusion (Definity). Infusion was interrupted to allow contrast clearance and images were acquired during subsequent contrast inflow. Myocardial videointensity was measured over time and peak contrast inflow rate was calculated. RESULTS: In pigs, partial coronary occlusion resulted in a 47 +/- 23% decrease in peak contrast inflow rate in the left anterior descending coronary artery perfusion territory (P < .05), which was reversed during reperfusion, without concomitant decrease in other perfusion territories. These changes were in agreement with microspheres. In human beings, adenosine increased peak contrast inflow rate to 278 +/- 123% of baseline (P < .05). CONCLUSION: The interruption of contrast infusion technique is a sensitive tool for accurate quantification of myocardial perfusion, which may constitute an alternative to currently used techniques.

Animals↗

Sudden infant death syndrome (SIDS)--standardised investigations and classification: recommendations.

Sudden infant death syndrome (SIDS) still accounts for considerable numbers of unexpected infant deaths in many countries. While numerous theories have been advanced to explain these events, it is increasingly clear that this group of infant deaths results from the complex interaction of a variety of heritable and idiosyncratic endogenous factors interacting with exogenous factors. This has been elegantly summarised in the "three hit" or "triple risk" model. Contradictions and lack of consistencies in the literature have arisen from diverse autopsy approaches, variable applications of diagnostic criteria and inconsistent use of definitions. An approach to sudden infant death is outlined with discussion of appropriate tissue sampling, ancillary investigations and the use of controls in research projects. Standardisation of infant death investigations with the application of uniform definitions and protocols will ensure optimal investigation of individual cases and enable international comparisons of trends.

Bacteriological Techniques↗

Limited survival in patients with carcinomatosis from foregut malignancies after cytoreduction and continuous hyperthermic peritoneal perfusion.

Peritoneal carcinomatosis is a frequent mode of metastasis in patients with gastric, duodenal, or pancreatic cancer. Survival in this setting is short and therapeutic options are limited. This analysis examines the outcomes of 18 patients treated with operative cytoreduction and continuous hyperthermic peritoneal perfusion. Eighteen patients (6 males and 12 females) with gastric (n = 9), pancreatic (n = 7), or duodenal (n = 2) cancer were treated on protocol. Patients underwent optimal cytoreduction (complete gross resection, 11; minimal residual disease, 7) and a 90-minute perfusion with cisplatin. Clinical parameters and tumor and treatment characteristics were analyzed. Survival curves were estimated using the Kaplan-Meier method. Procedures included gastrectomy (n = 8), pancreaticoduodenectomy (n = 3), and hemicolectomy (n = 2). After cytoreduction, patients had no evidence of residual disease (n = 11), fewer than 100 implants less than 5 mm (n = 1), more than 100 implants between 5-10 mm (n = 3), or multiple implants with greater than 1 cm (n = 3). Five patients received a postoperative intraperitoneal dwell with 5-fluorouracil and paclitaxel. There was one perioperative mortality, and complications occurred in 10 patients. The median progression-free survival was 8 months (mean, 10 months; range, 1-47 months) with a median overall survival of 8 months (mean, 18 months; range, 1-74 months). In this cohort, peritoneal perfusion with cisplatin used to treat foregut malignancies has a high incidence of complications and does not significantly alter the natural history of the disease. Investigation of novel therapeutic approaches should be considered.

Adenocarcinoma↗

Randomized, double-blind comparison of 1 mg/L versus 5 mg/L methoxsalen bath-PUVA therapy for chronic plaque-type psoriasis.

BACKGROUND: Bath-psoralen plus ultraviolet A (PUVA) radiation therapy is increasingly replacing oral PUVA because of its superior short- and long-term safety profile. Several investigations in recent years have led to a refinement of the bath-PUVA protocol; however, the optimal therapeutic concentration of methoxsalen in the bath water has as yet not been delineated. OBJECTIVES: The therapeutic efficacy and tolerability of bath-PUVA by using two different dilutions of methoxsalen (1 mg/L vs 5 mg/L or 0.0001% vs 0.0005%) were compared in 46 patients with chronic plaque-type psoriasis in a prospective, randomized, double-blind study. METHODS: Scores of the Psoriasis Area and Severity Index excluding psoriasis of the head (PASI(TUL)) and the Plaque Severity Index (PSI) were assessed at baseline and at biweekly intervals thereafter until (near)complete clearance or maximal improvement. In addition, methoxsalen plasma levels were determined immediately after the psoralen bath during the first week of treatment and treatment-related side effects were recorded throughout the entire study period. RESULTS: The median baseline PASI(TUL) score decreased from 11.7 (7.5-32.8) to 3.3 (0.6-1.2) (-72%) in the 1 mg/L methoxsalen group and from 10.8 (6.6-20.7) to 1.4 (03.2) (-87%) in the 5 mg/L methoxsalen group (P < .01). The median baseline PSI score decreased from 9 (6-12) to 3.1 (0.6-10) (-66%) in the 1 mg/L methoxsalen group and from 9.3 (7.3-12) to 1.6 (0-3.6) (-83%) in the 5 mg/L methoxsalen group (P < .01). The median cumulative UVA exposure dose was 25.4 (5.3-81.5) J/cm2 for 5 mg/L methoxsalen and 71.9 (20.7-587.3) J/cm2 for 1 mg/L methoxsalen (P = .001). The number of exposures (22 [11-29] vs 23 [11-34]) and treatment duration (43 [19-68] vs 44 [23-66] days) was comparable for both methoxsalen dilutions (P = .97). Median psoralen plasma levels were 0 (0-26) ng/mL after the 1 mg/L and 30 (0-64) ng/mL after the 5 mg/L methoxsalen immersion (P = .001). Mild to moderate adverse events were more common in the 5 mg/L methoxsalen group. LIMITATIONS: The conclusions of this randomized controlled study are limited by the relatively small sample size. CONCLUSIONS: Our data indicate that in bath-PUVA treatment the use of a high (5 mg/L) methoxsalen concentration is substantially more effective in clearing chronic plaque-type psoriasis than a low (1 mg/L) concentration.

Adult↗

Stereopsis and long-term stability of alignment in esotropia.

PURPOSE: Recent studies of infantile and accommodative esotropia (ET) have focused on stereoacuity as a final outcome measurement for judging the success or failure of treatment. The purpose of the present study was to extend this approach by evaluating whether the presence of stereopsis developing immediately after surgical alignment or optical correction plays a role in maintenance of long-term alignment. METHODS: Random-dot stereoacuity was assessed within 3 months of initial surgical alignment in 70 children with infantile ET and within 3 months of initial optical correction in 66 children with accommodative ET. At > or = 5 years of age, adverse outcomes were assessed including loss of alignment, amblyopia, and nil stereopsis. Risk-factor analysis was used to evaluate whether early nil stereopsis increased the risk for subsequent adverse outcomes. RESULTS: In the infantile ET cohort, early nil stereopsis was associated with a 3.6 times (95% confidence interval [CI] 2.4 to 4.1) greater risk of surgery for recurrent ET or consecutive exotropia and a 4.2 times (95% CI 3.3 to 4.4) greater risk for nil stereopsis at > or = 5 years of age. In the accommodative ET cohort, early nil stereopsis was associated with a 17.4 times (95% CI 3.3 to 32.2) greater risk of surgery for ET and a 32.2 times (95% CI 15.8 to 35.6) greater risk for nil stereopsis at > or = 5 years of age. CONCLUSION: Treatment protocols designed to optimize stereoacuity outcomes promote long-term stability of alignment.

Accommodation, Ocular↗

Characterization and sequence verification of thiolated deoxyoligonucleotides used for microarray construction.

During synthesis of thiolated deoxyoligonucleotides, side products can be formed. When used in the fabrication of microchips, the oligonucleotides have to be of high purity. We demonstrated the presence of impurities, which were not failure sequences from the synthesis. These products were identified and characterized using high-performance liquid chromatography (HPLC) and electrospray MS(/MS). The presence of the free thiol group was assessed by acrylamide derivatization. After reaction with acrylamide the correct compounds showed a 71 u mass shift and the major fragment ions could be assigned as 5' a-base and 3' w ions, similar as for unmodified DNA. The side products were unaffected by acrylamide, suggesting that the thiol group was modified. The oligonucleotide containing a species with a mass of 32 u higher was identified as 5' sulfinic acid containing molecule and was found as 45% of the total amount of a DNA 25 mer. Other components appeared to be dithio-linked oxidation products, present about 1 to 5% in a 10 mer and 15 mer deoxyoligonucleotide. The analyses were useful for optimizing the synthesis protocols.

Acrylamides↗

Study of the formation of perovskite type lanthanum ruthenates by heating their hydrous precursor.

Emanation thermal analysis (ETA), differential thermal analysis (DTA), thermogravimetry (TG), evolved gas analysis with mass spectrometric detection (EGA-MS), and X-ray diffraction (XRD) were used to investigate the formation of perovskite type lanthanum ruthenates on heating their hydroxide precursor in argon from 20 to 1200 degrees C. The co-precipitated lanthanum-ruthenium mixed hydroxide containing a small amount of carbonates was used as a precursor. The mass loss corresponding to the release of water and CO(2) from the precursor was determined by TG and EGA (MS), respectively. The ETA characterized the exposure of sample surface after release of water and CO(2), as well as microstructure development corresponding to the crystallization and structure ordering of LaRuO(3) and La(3.5)Ru(4.0)O(13) perovskite phases. The obtained information on formation of phases and their transformation is useful for optimizing their synthesis protocols for achieving the desired physical properties, and to estimate the thermal stability of these materials to be used as catalysts.

Journal Article↗

Apoptosis of monocytes and the influence on yield of monocyte-derived dendritic cells.

Monocyte-derived dendritic cells (DC) are currently under extensive evaluation as cell vaccines for cancer treatment. The requirement for large-scale cell products demands optimized and standardized protocols. However, the yield of DCs from inoculated monocytes is reported to be always lower than 50%. In this present study we investigated whether this cell loss was caused by the properties of the starting population of inoculated monocytes. CD14 cells were enriched by immunomagnetic-bead selection and analyzed for apoptosis by an annexin V/propidium iodide assay. We found that 37.8+/-11.1% (n=8) of freshly isolated monocytes from buffy coats of healthy donors underwent programmed cell death. Further analysis of the fate of apoptotic cells during differentiation suggested phagocytosis. Monocytes were differentiated with GM-CSF and interleukin-4 into a viable, non-apoptotic population of immature dendritic cells. Addition of tumor necrosis factor-alpha and prostaglandin E2 resulted in fully matured dendritic cells, which were evaluated by phenotypic analysis and by allogeneic and MHC class-I-restricted T-cell responses. About 90.2+/-16.7% of the non-apoptotic monocyte population differentiated to viable matured dendritic cells. These results indicate that the yield of dendritic cells is mainly influenced by the percentage of apoptotic cells in the inoculum, and this has implications for DC generation in clinical applications.

Annexin A5↗

Evaluation of pilocarpine effects on sweat proteome.

BACKGROUND: Sweat is increasingly recognized as a valuable, non-invasive biofluid for biomarker discovery, yet its composition depends on the stimulation method. This study aimed to determine how pharmacological induction with pilocarpine compares to physiologically induced sweat through exercise in shaping the sweat proteome. RESULTS: We analyzed thermoregulatory sweat from exercise, pilocarpine-induced sweat, and combined pilocarpine plus exercise sweat. Total protein concentrations were similar across conditions, but pilocarpine markedly increased proteomic diversity, with combined pilocarpine plus exercise sweat showing the highest number of identifications. The core sweat proteome remained stable, while pilocarpine selectively enriched low-abundance proteins involved in vesicular trafficking, cytoskeletal remodelling, and metabolism. Proteins linked to the canonical M3-Gq-PLC-Ca2+ pathway, including AQP5, CALML5, and CLIC1, were consistently enriched, confirming cholinergic activation. Pilocarpine-induced sweat also contained plasma-derived and immune-related proteins, reflecting enhanced secretion and reduced ductal reabsorption. CONCLUSIONS: Exercise yields a physiologically relevant but less complex proteome, pilocarpine-induced sweat produces a pharmacologically enriched yet biased profile, and combined pilocarpine plus exercise sweat maximizes protein detection at the expense of interpretability. These findings highlight the critical impact of stimulation paradigm on sweat proteomics and provide a reference framework for biomarker research. SIGNIFICANCE: This study employed LC-MS/MS to systematically characterize eccrine sweat and delineate how stimulation paradigms-exercise, pilocarpine, and their combination-shape its proteomic landscape. By demonstrating that pharmacological induction profoundly alters protein diversity and composition compared to physiologically induced sweat, these findings establish a critical benchmark for sweat-based biomarker research and highlight the need for paradigm-aware sampling strategies in clinical and translational contexts. Nonetheless, several methodological constraints warrant consideration: the limited sample size (five individuals per group), the exclusive inclusion of women under combined oral contraceptive treatment (21 active pills followed by 7 pill-free days), which restricts extrapolation to naturally cycling women, and the focus on healthy young adults (18-25&#xa0;years), limiting generalizability to older or clinically heterogeneous populations. Despite these limitations, this work provides a foundational framework for optimizing sweat collection protocols and advancing precision approaches in non-invasive diagnostics.

Pilocarpine↗

Optimized vaccination regimen linked to exhaustive screening approaches identifies 2 novel HLA-B7 restricted epitopes within hepatitis C virus NS3 protein.

Broad immune responses, in particular specific for the NS3 protein and mediated by both CD8+ and CD4+T lymphocytes, are thought to play a critical role in the control of hepatitis C virus (HCV) infection. In this study, we searched for novel HLA-B*0702 NS3 restricted epitopes following an optimized NS3NS4 immunization protocol in transgenic mice expressing HLA-B*0702 molecule. Combining predicted and overlapping peptides, we identified two novel epitopes, WPA10 (aa 1111-1120) and LSP10 (aa 1153-1162), which triggered significant IFN-gamma-producing T cell frequencies and high CTL responses. Both epitopes were shown to be immunogenic when used as synthetic peptides to immunize mice. The relevance of these epitopes to humans was demonstrated, as both were able in vitro to recall specific IFN-gamma and IL10-producing cells from peripheral blood mononuclear cells of HCV infected patients. Such epitopes enlarge the pool of NS3-specific CD8+T cell epitopes available to perform immunomonitoring of HCV infection and to develop vaccines.

Alleles↗

Assessment of the efficacy of functional food ingredients-introducing the concept "kinetics of biomarkers".

Functional foods are "foods and beverages with claimed health benefits based on scientific evidence". Health claims need to be substantiated scientifically. The future of functional foods will heavily rely on proven efficacy in well-controlled intervention studies with human volunteers. In order to have the maximum output of human trials, improvements are needed with respect to study design and optimization of study protocols. Efficacy at realistic intake levels needs to be established in studies with humans via the use of suitable biomarkers, unless the endpoint can be measured directly. The human body is able to deal with chemical entities irrespective of their origin, and the pharmaceutical terms "absorption, distribution, metabolism and excretion" have their equivalent when biomarkers are concerned. Whereas only "diurnal variation" or "circadian rhythm" is sometimes considered, little attention is paid to "kinetics of biomarkers". "Kinetics of biomarkers" comprises "formation, distribution, metabolism and excretion". However, this is at present neither an established science nor common practice in nutrition research on functional foods. As a consequence, sampling times and matrices, for example, are chosen on the basis of historical practice and convenience (for volunteers and scientists) but not on the basis of in depth insight. The concept of kinetics of biomarkers is illustrated by a variety of readily comprehensible examples, such as malaria, cholesterol, polyphenols, glutathione-S-transferase alpha, F2-isoprostanes, interleukin-6, and plasma triacylglycerides.

Biomarkers↗

Mechanobiology of mandibular distraction osteogenesis: finite element analyses with a rat model.

Three-dimensional finite element (FE) analyses were performed to characterize the local mechanical environment created within the tissue regenerate during mandibular distraction osteogenesis (DO) in a rat model. Finite element models were created from three-dimensional computed tomography image data of rat hemi-mandibles at four different time points during an optimal distraction osteogenesis protocol (i.e., most successful protocol for bone formation): end latency (post-operative day (POD) 5), distraction day 2 (POD 7), distraction day 5 (POD 10), and distraction day 8 (POD 13). A 0.25 mm distraction was simulated and the resulting hydrostatic stresses and maximum principal tensile strains were determined within the tissue regenerate. When compared to previous histological findings, finite element analyses showed that tensile strains up to 13% corresponded to regions of new bone formation and regions of periosteal hydrostatic pressure with magnitudes less than 17 kPa corresponded to locations of cartilage formation. Tensile strains within the center of the gap were much higher, leading us to conclude that tissue damage would occur there if the tissue was not compliant enough to withstand such high strains, and that this damage would trigger formation of new mesenchymal tissue. These data were consistent with histological evidence showing mesenchymal tissue present in the center of the gap throughout distraction. Finite element analyses performed at different time points during distraction were instrumental in determining the changes in hydrostatic stress and tensile strain fields throughout distraction, providing a mechanical environment rationale for the different levels of bone formation in end latency, and distraction day 2, 5, and 8 specimens.

Animals↗

A multi-laboratory evaluation of cryopreserved monkey hepatocyte functions for use in pharmaco-toxicology.

Ethical, economic and technical reasons hinder regular supply of freshly isolated hepatocytes from higher mammals such as monkey for preclinical evaluation of drugs. Hence, we aimed at developing optimal and reproducible protocols to cryopreserve and thaw parenchymal liver cells from this major toxicological species. Before the routine use of these protocols, we validated them through a multi-laboratory study. Dissociation of the whole animal liver resulted in obtaining 1-5 billion parenchymal cells with a viability of about 86%. An appropriate fraction (around 20%) of the freshly isolated cells was immediately set in primary culture and various hepato-specific tests were performed to examine their metabolic, biochemical and toxicological functions as well as their ultrastructural characteristics. The major part of the hepatocytes was frozen and their functionality checked using the same parameters after thawing. The characterization of fresh and thawed monkey hepatocytes demonstrated the maintenance of various hepato-specific functions. Indeed, cryopreserved hepatocytes were able to survive and to function in culture as well as their fresh counterparts. The ability for synthesis (proteins, ATP, GSH) and conjugation and secretion of biliary acids was preserved after deep freeze storage. A better stability of drug metabolizing activities than in rodent hepatocytes was observed in monkey. After thawing, Phase I and Phase II activities (cytochrome P450, ethoxycoumarin-O-deethylase, aldrin epoxidase, epoxide hydrolase, glutathione transferase, glutathione reductase and glutathione peroxidase) were well preserved. The metabolic patterns of several drugs were qualitatively and quantitatively similar before and after cryopreservation. Lastly, cytotoxicity tests suggested that the freezing/thawing steps did not change cell sensitivity to toxic compounds.

Adenosine Triphosphate↗

Routine MR examination of the knee using parallel imaging.

AIM: To demonstrate the feasibility and the clinical value of parallel imaging of the knee. METHODS: A pair of flex coils was used for the parallel imaging. Before optimization of the protocol, qualitative and quantitative analysis was performed by volunteer and phantom study. Two separate consecutive groups of 80 patients were examined with or without parallel imaging and compared with the arthroscopic results. RESULTS: Parallel imaging obtained a total of 164 images of six series in less than 20 min. Compared with conventional imaging, the parallel imaging appeared slightly noisy with an 83% relative signal-to-noise ratio. Demarcation of the cruciate ligaments and menisci were rated equivalent. For the patients study, the parallel imaging delineated ligament and meniscus pathologies with accuracies of over 93%. CONCLUSION: Parallel MR imaging of the knee enables significant reduction of scan time as well as preserving diagnostic results.

Adolescent↗

Osmometric behavior of mouse oocytes in the presence of different intracellular sugars.

In order to successfully cryopreserve oocytes using low concentrations of intracellular sugars, it is important to characterize their osmotic response in the presence of these intracellular sugars. In the present study, murine (B6D2F1) oocytes were microinjected with 0.8M glucose, trehalose or stachyose solutions to achieve an intracellular concentration equivalent to 0.1M, and then exposed to hypertonic solutions of increasing strength by supplementing an isotonic solution with 0.2, 0.3, 0.5, and 0.7 M of trehalose. Analysis of volumetric response of microinjected oocytes showed that the oocytes behaved as ideal osmometers in the presence of intracellular sugars and satisfied the Boyle van't Hoff relationship. Extrapolation of the osmotically inactive fraction (V macro b) from the Boyle van't Hoff relationship yielded values of 0.188+/-0.028, 0.212+/-0.042, 0.197+/-0.044, and 0.211+/-0.042 for control, glucose, trehalose and stachyose-injected oocytes, respectively. The present data revealing osmometric behavior of mouse oocytes in the presence of different intracellular sugars are important for the optimization of cryopreservation protocols using sugars.

Animals↗

Consistent transient transfection of DNA into non-transformed human and murine T-lymphocytes.

The ability to analyze transcriptional regulation in non-transformed T-cells has been hampered by the inability to reproducibly transiently transfect these cells with DNA constructs. We have previously demonstrated that normal human whole mononuclear and CD4 T-cells can be consistently transiently transfected with plasmid DNA. Human cells were most receptive to plasmid DNA uptake between 19.5 and 20 h after prestimulation with a submitogenic dose of the polyclonal T-cell activator, PHA. Here we report an alteration and optimization of this protocol for non-transformed murine splenic T-cells, using concanavalin A instead of PHA as the preactivation stimulus. When coupled with the high sensitivity of luciferase reporter gene constructs, this protocol facilitates the analysis of a variety of T-cell-specific promoters in non-transformed T-cells. In addition, we directly demonstrate that murine T-cells are specifically transiently transfected among a population of whole mononuclear cells by using an expression vector for green fluorescent protein.

Animals↗