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At least 19 recordsLinked to original sources
PubMed1977

Reproducibility of data on steady-state gas exchange and indices of maldistribution of ventilation and blood flow.

The reproducibility of data on steady-state gas exchange and arterial blood gas levels was examined in 45 patients with similar pathophysiologic abnormalities (idiopathic scoliosis) by comparing the data obtained during two sequential periods breathing air. Comparison in all patients of 12 variables by paired t-test demonstrated statistically significant differences in the following three variables: the ratio of physiologic dead space to tidal volume (Vd/TV), the alveolar-arterial oxygen pressure difference (P[A-a]O2), and the arterial oxygen tension. By excluding four patients whose respiratory quotient was greater than two standard deviations from the mean value and one patient with a marked change in the pattern of ventilation, only the Vd/TV was significantly different (P less than 0.05). The range of the coefficients of variation was wide. The highest, which was for P(A-a)O2, was 18.8 percent; the majority were in range of 6 to 13 percent (minute ventilation, TV, frequency, oxygen consumption and carbon dioxide production, respiratory quotient, Vd/TV, dead space, and alveolar ventilation), and the coefficients of variation of partial pressure of oxygen and carbon dioxide in the arterial blood were, respectively, 3.6 and 3.4 percent.

Blood Gas Analysis↗
PubMed2026

Community-driven advances in computational mass spectrometry: The perspective of EuBIC-MS members.

Advances in data acquisition, artificial intelligence, and integrative bioinformatics are driving the rapid evolution of computational mass spectrometry, and in turn, transforming modern proteomics, metabolomics, and lipidomics. These developments have greatly increased the scale and complexity of mass spectrometry data, underscoring the importance of evolving accurate, transparent, efficient and reproducible data processing workflows. Addressing these challenges requires collaborative innovation that brings together expertise in software engineering, statistics, and biology. The European Bioinformatics Community for Mass Spectrometry (EuBIC-MS), an initiative of the European Proteomics Association (EuPA), fosters a culture of open, community-driven development through its biennial Developers Meetings and Winter Schools. This commentary summarizes the scientific background and outcomes of the EuBIC-MS Developers Meeting 2025, which took place in Novacella, Italy. Three keynote presentations highlighted major frontiers in the field: deep proteome and phosphoproteome profiling, text mining for protein-protein interaction extraction, and scalable proteomics for AI-driven drug discovery. Seven community-selected hackathons addressed emerging challenges such as single-cell proteomics data analysis, FAIR metadata extraction, deep learning frameworks, R-Python interoperability, and DIA validation. Together, these efforts demonstrate the potential for scientific and technical innovation to arise from open collaboration, and highlight how community-driven initiatives can accelerate progress in computational mass spectrometry. SIGNIFICANCE: Modern proteomics increasingly depends on computational advances to translate complex, high-dimensional data into biological knowledge. The EuBIC-MS Developers Meeting 2025 exemplifies how community-driven collaboration can directly accelerate this process by bringing together experts from bioinformatics, statistics, and experimental proteomics to co-develop open, interoperable, and reproducible analytical tools. By fostering shared software frameworks, transparent benchmarking, and collaborative problem solving, the EuBIC-MS community helps ensure that technological innovation translates into reliable biological insights. This collaborative model strengthens the foundation for quantitative, system-level understanding of proteomes and establishes a sustainable path for integrating artificial intelligence and next-generation data acquisition into routine biological discovery. This commentary shows some current highlights in the field of computational mass spectrometry and community-based approaches undertaken during the most recent Developers Meeting to solve these challenges. The approaches discussed and initiated during the meeting - ranging from deep proteome profiling and phosphosite mapping to text mining, single-cell data analysis, and FAIR metadata extraction - address key bottlenecks that currently limit the biological interpretability and comparability of proteomics data.

Mass Spectrometry↗
PubMed1978

A scheme for the evaluation of methods in clinical chemistry with particular application to those measuring enzyme activities. Part II: analysis of data and performance assessment.

Recommendations are made concerning the editing of day-to-day reproducibility data for establishment of precision in the evaluation of a clinical chemistry method. The concept of diagnostic and equalized diagnostic indices is introduced together with formulae for their generation from the usual precision and accuracy data acquired in method evaluations. These indices allow direct comparison of data obtained from procedures for measuring enzyme activities which employ a variety of experimental conditions and units in their protocols. The equalized diagnostic index permits assessment of the suitability of the normal range assignment. Permissible limits of variation (PLV) and permissible limits of discrepancy (PLD) have been developed empirically from detailed examination of data from method evaluations and proficiency testing surveys in the published literature. The application of the diagnostic indices and the two permissible limits of criteria have been illustrated using data from the assessment of 19 kits measuring CPK activity. The inconsistency of the correlation coefficient in method comparisons is confirmed.

Canada↗
PubMedDate not supplied

Syringing as a method of cell dispersal. I. Effect on intermediate and superficial squamous cells.

Mechanical shear in the form of syringing was applied to human gynecologic cytology specimens in an effort to disperse cell clumps. The percentage of single squamous cells achieved with the optimum conditions is generally 70 to 100 per cent. Syringing with a constant pressure device produces a high yield of single squamous cells without the concurrent high cell loss as often observed using enzymatic or chemical procedures. Data presented demonstrate that the slide preparation and clump evaluation procedures used for this study yield reliable and reproducible data. Studies varying stroke number and plunger pressure were completed and conditions for maximum dispersal were established.

Cell Separation↗
PubMed1979

[Evaluation of accuracy comparing three types of urological manometers (author's transl)].

Manometrical examinations of the female urinary bladder are important in the field of urodynamic diagnosis. Accuracy in these measurements is a prerequisite for the reproducibility of the results. In this study, three types of urological manometers, differing in their principles of measurement, were tested for their physical and technical properties. Pressure was measured with a membrane manometer (instrument A) with Statham elements (instrument B), and with a micro-transducer (instrument C). The results using Statham elements and micro-transducers were exactly reproducible and varied only in their interference with external factors, which affect the quality of the results in clinical routine. Concerning the physical technique of measurement, instrument C with micro-transducers gives the most accurate results and is the easiest one to manage. For research and clinical routine it is superior to instrument B. It supplies reproducible data which are independent of external parameters such as the patient's position, attention and the way the instrument is set up. Our results only urodynamical measurements using micro-transducers can be taken as absolute measurements of excellent accuracy and are comparable among themselves as well as with other absolute measurements for long-term series of measurement. Using a membrane manometer (instrument A), measurements were hardly reproducible so that these results can be accepted as orienting data only.

Evaluation Studies as Topic↗
PubMed1977

Electron-capture GLC determination of nanogram to picogram amounts of isosorbide dinitrate.

A GLC method for the determination of plasma isosorbide dinitrate using electron-capture detection is described. The organic nitrates are especially suited for electron-capture detection if the detector temperature is optimized for maximum sensitivity, e.g., 175 degrees. Proper maintenance of the detector and column assures reproducible data in the low nanogram range. The extraction procedure described is simple, efficient, and expedient for processing large numbers of samples. The method was used to study plasma levels in four human volunteers after a single dose of a 5-mg chewable isosorbide dinitrate tablet. Concentration levels of isosorbide dinitrate as low as 0.5 ng/ml of plasma can be measured by this procedure.

Adult↗
PubMed1979

Application of linear system analysis to the horizontal vestibulo-ocular reflex of the alert rhesus monkey using pseudorandom binary sequence and single frequency sinusoidal stimulation.

Horizontal eye movements of the alert rhesus monkey resulting from both pseudorandom binary sequence (PRBS) and single frequency sinusoidal rotational stimulation were analyzed using a PDP 11/40 computer in order to generate gain, phase, and coherence estimates at discrete frequencies between 0.008 and 1.28 Hz. A computer simulation of vestibular induced eye movements was used to validate our analysis procedures and to determine the effects of digital noise. Frequency domain transfer functions derived from gain and phase estimates revealed that the responses to PRBS stimulation and to single frequency sinusoids were not appreciably different. PRBS testing was accomplished in approximately one third the time required for sinusoidal testing and yielded highly reproducible data. We conclude that PRBS stimulation is a reliable and efficient method for assessing linear system parameters of the horizontal vestibulo-ocular reflex. PRBS testing may be particularly advantageous in studies of vestibulo-oculomotor plasticity in which rapid assessment of alterations in system dynamics is essential.

Animals↗
PubMed1979

Determination of erythrocyte amino acids by gas chromatography.

Erythrocyte amino acid levels were determined, by gas chromatography, in a group of 34 normal human adults. No significant sex or age correlations were noted. A method for the quantitative gas chromatographic analysis of free amino acids in erythrocytes is described. Following hemolysis and deproteinization the amino acids were isolated on a cation-exchange resin. Glutathione was removed from the amino acid mixture by adsorption on an anion-exchange resin. Following conversion to their N-acetyl-n-propyl esters, 19 amino acids were separated and quantitated by gas chromatography on a single column in 18 min. Typical reproducibility data indicate that a coefficient of variation of 2-5% is attainable.

Adult↗
PubMed1977

Tension generation by threads of contractile proteins.

Threads of contractile proteins were formed via extrusion and their isometric tensions and isotonic contraction velocities were measured. We obtained reproducible data by using a new and sensitive tensiometer. The force-velocity curves of actomyosin threads were similar to those of muscle, with isometric tensions of the order of 10g/cm2 and maximum contraction velocites of the order of 10(-2) lengths/s. The data could be fitted by Hill's equation. Addition of tropomyosin and troponin to the threads increased isometric tension and maximum contraction velocity. Threads which contained troponin and tropomyosin required Ca++ for contraction and the dependence of their isometric tension on the level of free Ca++ was like that of muscle. The dependence of tension or of contraction velocity upon temperature or upon ionic strength is similar for actomyosin threads and muscle fibers. In contrast, the dependence of most parameters which are characteristic of the actomyosin interaction in solution (or suspension) upon these variables is not similar to the dependence of the muscle fiber parameters. The conclusion we have drawn from these results is that the mechanism of tension generation in the threads is similar to the mechanism that exists in muscle. Because the protein composition of the thread system can be manipulated readily and because the tensions and velocities of the threads can be related directly to the physiological parameters of muscle fibers, the threads provide a powerful method for studying contractile proteins.

Actins↗
PubMed1979

Histometric analysis of human skin in organ culture.

A histometric method is used for the study of human skin kept in organ culture in a defined medium for up to 10 days. The method provides quantitative, reproducible data on tissue survival, cell migration, and cellular differentiation (keratinization). With this method, the behavior of epidermal skin tissue can be effectively monitored during organ culture. As quantitative data are obtained, even subtle changes can be accurately demonstrated, and accumulated data may be subjected to statistical analysis. The various applications of this method are pointed out.

Adult↗
PubMed1977

Percutaneous cardiac puncture in domestic pigs.

Blood sampling by percutaneous cardiac puncture was carried out in 69 domestic pigs. The procedure was shown to be safe and to produce reproducible data. The technique can be carried out without anaesthesia. Repeated sampling is possible over minutes, hours or days, and a wide range of sample volumes can be achieved by this technique.

Animals↗
PubMed1978

The noninvasive diagnosis of thrombophlebitis in the lower extremities: clinical value of plethysmography combined with augmentation methods and a new scoring system.

Venous impedance plethysmography and respiratory-compression Doppler augmentation responses have proved to be diagnostically valuable in suspected thrombophlebitis of the lower extremities. These noninvasive methods can provide quantitative and reproducible data on the basis of which the presence of increased deep venous resistance can be confirmed, suspected, or doubted. A new scoring system for the composite evaluation of data from 100 consecutive patients with possible thrombophlebitis, pulmonary embolism, or both, is presented. These procedures assume added importance in view of the diagnostic limitations, and even potential hazards, of other methods. These methods indluce lung scanning, radioactive fibrinogen scanning, venography, and pulmonary angiography. Serial studies can be performed with impunity for following highrisk patients and evaluating various therapeutic or prophylactic measures. The importance of monitoring the femoral-popliteal segment is emphasized, because of the greater propensity for massive pulmonary thromboembolism from thrombi in these veins than in the calf vessels. Clinical observations coupled with these studies underscore the fallacy of several widely-held diagnostic biases pertaining to deep venous thrombosis and pulmonary thromboembolism. The long-term followup of 12 patients in whom inferior vena cava unbrellas has been inserted for life-threatening pulmonary embolism is presented. The possible propensity to deep vein thrombosis from vitamin E therapy is raised.

Adult↗
PubMed2026

Single-cell RNA sequencing reveals disease associated changes in brain endothelial cells in the 5XFAD mouse.

Vascular dysfunction is a key contributor to Alzheimer’s disease (AD) pathology, where changes to the endothelium and its crucial role in maintaining blood-brain barrier (BBB) integrity have been of particular emphasis. The transgenic 5XFAD (5X Familial Alzheimer’s Disease) mouse model, which exhibits AD-related amyloidosis through FAD associated mutations in amyloid precursor protein (APP) and presenilin-1 (PS1), has become a widely adopted preclinical model in AD-related research studies. The need for cross-study standardization, accessibility, and data reproducibility has led to the widespread implementation of the C57BL/6J genetic background for maintaining this model. However, its reliability for studying vascular dysfunction and BBB alterations has been questioned due to conflicting reports in the literature. This variation is often attributed to the previously documented protective nature of the C57BL/6J background and loss of genetic background diversity. Since prior studies have mostly relied on imaging or functional assays, we herein utilized single-cell RNA sequencing (scRNAseq) to investigate AD-related molecular changes to endothelial cell populations in the 5XFAD mouse model. To initially build this resource, we focused on 12-month-old male mice, which revealed differentially expressed genes between 5XFAD and wildtype animals that mapped to signaling pathways involved in DNA damage, immune reactivity, and inflammation, among others. Many of these transcriptomic changes were zonated along the arteriovenous axis and occurred in AD genome-wide association study (GWAS) risk-associated genes. Overall, we anticipate this resource will help clarify the use of the 5XFAD model for studying AD-associated vascular changes and provide the foundation for expanded molecular profiling of brain endothelial cells under AD-associated conditions.

Animals↗
PubMed1976

[Submicroscopic structure of collagen--a basis for the interpretation of corresponding polarization-optical and histochemical findings].

In view of new possibilities of acquiring relatively quantitative information about the molecular structure of collagenous fibres in histological section with the help of polarization and histochemical methods a survey is given of the most important aspects of the molecular structure of collagen in connection with the formation of "cross-links", giving due attention to the role of functional groups. These create the basis for interpreting morphological findings covering free amino-groups of lysin and hydroxylysin, guanidine groups of arginine and carboxyl groups of glutamic acid and asparaginic acid, gained by adding phenol or toluidine blue to collagenous fibres and by performing path difference measurements. References made to the applicability of this polarization-histochemical method in clinical research and diagnostics, in gathering reproducible data on processes of development or growth and aging and pathological changes in collagen are intended to encourage wide use of this examination technique in practice.

Age Factors↗
PubMed1979

[Ultrasonic doppler technique in angiology (author's transl)].

The ultrasonic Doppler technique is a simple, non-stressing and harmless method of angiological investigation requiring little time. Today it is considered to be the best-suited procedure among the non-invasive instrumental methods in angiological diagnosis. It provides well reproducible data with regard to peripheral arterial blood flow and highly valuable information on functional conditions in the area of carotid flow and in the iliofemoral venous system. This method can be recommended unreservedly for use in general practice as well.

Arterial Occlusive Diseases↗
PubMed1975

Development of a microculture system for stimulation of chicken peripheral blood lymphocytes with concanavalin A.

A microculture system in conjunction with a semiautomatic multiple sample harvester (SAMSH) was used to study the in vitro properties of chicken peripheral lymphocytes. This new procedure enabled doing rapid multiple tests, using relatively few cells, and was highly reproducible. Data were presented to show many variables that are involved in studying the concanavalin A (Con A) response of chicken lymphocytes in a microculture system. Analysis indicated that the conditions for optimal Con A stimulation as measured by incorporation of 3H-TdR include: (a) use of 2 x 10(6) cells per culture in RPMI 1640 culture medium in the absence of any serum, (b) use of 0.4 mug of Con A per culture, (c) incubation at 37 degrees C for 72 hours, and (d) addition of 1 muCi of 3H-TdR to each culture 12 to 24 hours prior to termination. This technique could be used to monitor immunocompetence of the chicken.

Animals↗
PubMed1979

High pressure liquid chromatographic determination of carbohydrates in food products: evaluation of method.

A high pressure liquid chromatographic (HPLC) method for determining 5 common carbohydrates in food products was evaluated. Reproducibility data were generated showing a relative standard deviation of 2.8%. Recovery studies on a variety of foods gave an average recovery of 98.8%. The HPLC data for 3 varieties of ready-to-eat cereals were compared with data from 4 independent laboratories using current AOAC chemical methods. The HPLC mean values differed from the chemical mean values by 3.2%.

Chromatography, High Pressure Liquid↗