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Results for “Structural validation”

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PubMed2026

Specific Instruments for Caregiving Competence Among Family Caregivers of Cancer Patients: A COSMIN Systematic Review of Psychometric Properties.

OBJECTIVE: To evaluate and summarize the psychometric properties of specific instruments for caregiving competence among family caregivers of cancer patients. METHODS: Systematically searched eight databases for studies published up to November 2025. The methodological quality and psychometric properties of the instruments were evaluated using COSMIN 2.0. Evidence grades were rated using the modified GRADE system (four grades: "High," "Moderate," "Low," and "Very Low"), and recommendations were formulated (Category A: recommended, Category B: potential with further validation, and Category C: not recommended). RESULTS: Seven studies were included, comprising three specific instruments: the Care Competency Scale for Family Caregivers in Home Palliative Care (CCSHPC) (n = 1), the Caregiver Caregiving Self-Efficacy Scale-Oral Cancer (CSES-OC) (n = 1), and the Caring Ability of Family Caregivers of Patients with Cancer Scale (CAFCPCS) (n = 5). Both the CCSHPC and CAFCPCS received Category B recommendations, demonstrating "adequate" content validity with evidence grades rated "very low" and "low," respectively. The CAFCPCS also shows good structural validity ("moderate") and internal consistency ("low") in some cultural contexts. The CSES-OC is a Category C recommendation, with high-quality evidence indicating "inadequate" criterion validity. CONCLUSION: Few specific instruments exist, and most did not strictly follow COSMIN guidelines. The CAFCPCS is provisionally recommended based on relative evidence superiority rather than complete psychometric validation. Further cross-cultural and localized instrument development is warranted. IMPLICATIONS FOR NURSING PRACTICE: Use well-validated specific instruments to identify strengths and weaknesses in the caregiving competencies of family caregivers of cancer patients, enabling them to deliver high-quality home-based cancer care.

Female↗

PubMed2026

Computational prediction of a multi-epitope Human Metapneumovirus vaccine candidate through integrated reverse vaccinology and pan-genomic approaches.

Human metapneumovirus (HMPV) is a primary cause of global respiratory infections yet no approved vaccine currently exists. This study computationally predicts a multi-epitope vaccine candidate using a diverse dataset of 65 HMPV sequences spanning five continents. Following the screening of lead proteins for antigenicity and virulence, fifteen highly conserved MHC-I, MHC-II and B-cell epitopes were prioritized. These were integrated with a putative L7/L12 adjuvant using optimized AAY, GPGPG, and KK linkers to design three constructs (HMPV_V1-V3). Structural validation identified HMPV-V2 as the lead candidate that exhibits a Z-score of-5.24 and 87.7% of residues in favored Ramachandran regions indicating excellent stereochemical quality and structural stability. In silico docking indicated a strong predicted binding affinity between HMPV-V2 and the TLR4 receptor (energy: -969.2). Immune simulations predicted a robust adaptive response characterized by high IgG1 titers, memory B-cell maturation, and a Th1-dominant cytokine profile. Furthermore, molecular dynamics simulations suggested exceptional structural integrity for HMPV-V2, maintaining a low RMSD of 8.213 and RMSF of 0.737 throughout the simulation. Optimized in silico cloning into the pET28a (+) vector indicated a high potential for protein expression in E. coli systems. While these findings provide a theoretically grounded blueprint for vaccine development, this study is entirely computational and lacks experimental validation. Further in vitro and in vivo testing is required to confirm the actual safety and immunogenicity of the proposed candidate.

Metapneumovirus↗

PubMed2025

Genomic prediction and genome-wide association study for liver abscesses in crossbred beef cattle.

Liver abscesses are a concern in feedlot cattle, and little is known about the role of genetics in their development. This study aimed to estimate genetic parameters and to identify single-nucleotide polymorphisms (SNPs) associated with liver abscesses. Crossbred cattle representing 18 breeds in the U.S. Meat Animal Research Center Germplasm Evaluation Program were phenotyped for liver abscesses at slaughter (n = 9,044). Seventeen percent of cattle had liver abscesses. These cattle had genotypes that were imputed to sequence variant genotypes. After filtering and quality control, 340,723 SNPs were used in the analysis. Liver abscess prevalence was modeled with a single-step genomic best linear unbiased prediction (ssGBLUP) threshold model using a Bayesian framework. The model included contemporary group (sex, treatment group, and slaughter date), additive genomic, and residual effects. Genomic heritability was 0.039 (95% highest posterior density = 0.005, 0.081), which was very small. To assess prediction quality, a 5-fold random cross-validation structure was used. Method Linear Regression was used to assess accuracy, bias, and dispersion by comparing estimated breeding values (EBV) from full and reduced analyses. Cross-validation metrics showed EBV based on genotypes had 0.05 reliability (SD < 0.01) with no bias relative to EBV based on genotypes and phenotypes. For the genome-wide association study, SNP effects were back calculated from the EBV solutions from ssGBLUP. No SNPs were associated with liver abscesses at a Benjamini-Hochberg adjusted 0.05 significance level. Although a large dataset was used, this result was because of the low genomic heritability and imprecise EBV used to calculate SNP effects. Based on these results, environmental factors contribute to most of the variation in liver abscesses. Genetic selection to reduce liver abscesses would be slow because of the low genomic heritability, measurement late in life, and inability to measure breeding animals. A faster approach would be finding additional environmental interventions that maintain animal performance.

Animals↗

PubMed1992

Factor study of the Geriatric Depression Scale.

A sample of 234 people between the ages of 60 and 95 was studied using the Brink-Yesavage Geriatric Depression Scale (GDS). The GDS has good concurrent validity with the Hamilton Rating Scale for Depression with the Melancholia Scale (r = 0.77), which confirms the clinical utility of this scale. A factor analysis of principal components with an oblimin rotation was performed. The results obtained imply that structural validation cannot be made in relation to Beck's cognitive model of depression. It can be concluded that the elimination of the somatic items does not add any theoretical correspondence with the model, as the factors tend to group the various items into one dimension.

Aged↗

PubMed2025

Leveraging chemical synthesis to discover metabolites from the gut microbiome.

The gut microbiome has the biosynthetic potential to make a variety of secondary metabolites or natural products, which serve as molecular messages between cells and organisms. These chemical signals are capable of affecting physiology and behavior in real time, and are, therefore, bioactive and can exhibit medicinal properties including anticancer, antimicrobial, or immunomodulating activities. It is clearly important to identify signaling molecules in the human gut, but elucidating their chemical structures can be challenging since traditional isolation methods are typically not available. The discovery of microbiome-related metabolites requires multidisciplinary collaboration, where chemical synthesis often plays an essential role. This review highlights examples where synthetic chemistry was used to study novel metabolites produced by the gut microbiota. In the first part, we describe examples where organic synthesis was utilized in traditional contexts, as a last step for validating structures and sourcing material for biological testing. The final section of this review discusses next-generation applications for chemical synthesis, where integration with metabolomic or genomic analysis simultaneously uncovers both structural and biological information about small molecules from the gut.

Gastrointestinal Microbiome↗

PubMed2026

Regional genomic analysis of lineage distribution and transferable multidrug resistance among chicken-associated Salmonella Kentucky isolates in China.

Salmonella enterica serovar Kentucky is an important multidrug-resistant foodborne pathogen in the poultry meat supply chain. Although recent broader genomic studies have elucidated the population structure and epidemiological significance of major lineages in China (e.g., ST198 and ST314), the regional dynamics within local poultry supply chains remain insufficiently characterized. In this study, 31 chicken meat-derived isolates from Shanghai and 39 publicly available genomes from China were analyzed using antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis, conjugation experiments, and complete sequencing of representative plasmids. This enabled a systematic characterization of the molecular epidemiological features of the population and the mechanisms underlying resistance dissemination. Population genomic analysis revealed a lineage composition markedly different from the global epidemiological pattern: ST314 was the predominant sequence type among the Shanghai chicken-derived isolates (74.2%), whereas the internationally recognized high-risk clone ST198 accounted for only 25.8% of the local isolates. However, risk stratification analysis indicated that although ST198 was detected less frequently, it carried a significantly greater burden of acquired resistance genes and therefore represented a higher-risk resistant lineage. Functional and structural validation further elucidated the molecular basis of resistance dissemination within this high-risk lineage. Conjugation experiments confirmed the co-transfer of a multidrug resistance module carrying blaTEM-1 and blaCTX-M-267 to the recipient strain Escherichia coli J53. Complete plasmid analysis revealed that these two β-lactam resistance genes were co-localized on a 242-kb transferable plasmid flanked by Tn1331, Tn3, and multiple transposase-associated elements, thereby providing a structural basis for their horizontal transfer. This study provides important molecular epidemiological evidence for lineage-specific surveillance and risk-stratified control of resistant Salmonella in the poultry meat supply chain and further underscores the need for continuous monitoring of mobile genetic elements within a One Health framework.

Animals↗

PubMed1992

Outcomes management in heart valve replacement surgery: early experience.

Recent efforts at reducing health care expenditures and practice variations have focused attention on treatment appropriateness, patient preference, and quality of life as important elements of treatment evaluation. These characteristics of medical treatment can be assessed by administration of a structured, valid health status assessment questionnaire before and at fixed intervals following treatment, and standardized scores may be compared to normal scores derived from healthy, untreated populations. One hundred valve replacement patients completed a standardized questionnaire, the 'SF-36', preoperatively and at 1- and 6-months postoperatively. Preoperatively, valve replacement patients are substantially impaired in their physical capacity, their ability to function in important roles, and their vitality. At one month, they report significant decrements in social and role functioning and in pain which we attribute to the trauma of surgery and recovery. At six months, mean scores approximate those for sex- and age-matched normals except for persistent moderate impairment in role functioning. Post-operative functional impairment is greatest for those undergoing mitral valve replacement, particularly when coronary artery grafts are performed concurrently, and for patients receiving bioprosthetic valves. Structured health status assessment provides a useful adjunct to other methods of assessing clinical status and evaluating treatment outcomes.

Aged↗

PubMed1992

The measurement of attitudes towards and beliefs about pain.

This study compared the psychometric properties of two scales designed to measure attitudes towards and beliefs about pain. The Survey of Pain Attitudes (Revised) SOPA(R) (Jensen and Karoly 1987) and the Pain Beliefs and Perceptions Inventory (PBPI) (Williams and Thorn 1989) were examined in terms of internal consistency, discriminant validity, factor structure, construct validity and sensitivity to age and gender effects. Results provided strong support for the SOPA(R) as a useful measurement tool for use with patients with chronic low back pain. Further work is suggested for the PBPI, as the reported factor structure was not replicated. Discussion centered around the possible reasons for this finding, with issues such as the possible orientation of different treatment facilities, the possible differences in attitudes between patients with different types of pain, and the possible influence of length of years in pain or the receipt of workers compensation payments being considered.

Adult↗

PubMed2026

Instruments for measuring body image in breast cancer patients: a systematic review of measurement properties.

PURPOSE: To evaluate the psychometric properties of PROMs for measuring body image in breast cancer patients. METHODS: In December 2024, a psychometric systematic review was performed in the nine databases. The COSMIN checklist was employed to evaluate the methodological quality and psychometric properties of the included body image measures. The level of evidence was assessed using the GRADE framework, and final recommendations were formulated for the scale. RESULTS: Thirty-eight articles evaluating fifteen PROMs were included in this review. Structural validity, internal consistency, and hypothesis testing had been most frequently evaluated. Measurement error had not been assessed for all PROMs. Twelve instruments show potential application value but require further research. The BAS-BC, PSPP, and ASI-R are not recommended for use, as these instruments do not meet the strict COSMIN thresholds for full recommendation. CONCLUSION: The BIS can be recommended as a temporary screening tool for assessing body image outcome in clinical practice. The BIRS can be tentatively advised for measuring specific postoperative body image changes. However, further comprehensive studies are required to validate the psychometric properties of existing PROMs.

Female↗

PubMed1979

Polypeptide composition of the purified photosystem II pigment-protein complex from spinach.

The Photosystem II pigment-protein complex, the chlorophyll alpha-protein comprising the reaction center of Photosystem II, was prepared from EDTA-treated spinach chloroplasts by digitonin extraction, sucrose-gradient centrifugation, DEAE-cellulose column chromatography, and isoelectrofocussing on Ampholine. The dissociated pigment-protein complex exhibits two polypeptide subunits that migrate in SDS-polyacrylamide gel with electrophoretic mobilities corresponding to molecular weights of approximately 43,000 and 27,000. the chlorophyll was always found in the free pigment zone at the completion of the electrophoresis. Heat-treatment of the sample (100 degrees C, 90 s) for electrophoresis caused association of the two polypeptides into large aggregates. It is concluded that these two polypeptides, 43,000 and 27,000, are valid structural or functional components of Photosystem II pigment-protein complex.

Chloroplasts↗

PubMed1990

The role of anxiety and depression in the irritable bowel syndrome.

Using a reliable and valid structured diagnostic interview scale (ADIS-R), and patients with careful medical characterization, we found significantly more diagnosable psychopathology, particularly anxiety disorders, among treatment seeking patients with irritable bowel syndrome than among comparable age and sex samples of treatment seeking patients with Inflammatory Bowel Disease. Significant differences were also found on the Hamilton Anxiety Rating Scale and Hamilton Rating Scale for Depression between IBS patients and the IBD patients and controls, who did not differ. Comparable levels of psychiatric disorder among parents of probands were found in all three groups. The results are consistent with Latimer's (1983) notion of IBS patients being a subclass of 'neurotics'.

Adult↗

PubMed1991

Predictive QSAR models for estimating biodegradation of aromatic compounds.

The development of valid structure biodegradation relationships (SBRs) is restricted by the lack of reproducible published data and by the considered endpoint of degradation data. A classification scheme is required for comparative evaluation of degradation data obtained by different test methods. SBRs based on substructure indicators are available for application to most compounds, but the reliability is still uncertain. SBRs based on physico-chemical parameters are only available for a few classes of compounds based on specific test methods. A combination of several SBRs covering the various transformation pathways provides a promising tool for predicting biodegradability. Two models describing biodegradation are introduced.

Biodegradation, Environmental↗

PubMed1991

Dimensional measurement of seasonal variation in mood and behavior.

Recent epidemiologic studies have found that the behaviors that characterize seasonal affective disorder (SAD) show seasonal variation in 92%-95% of the general population, suggesting that seasonal variation in behavior and mood is a continuous, dimensional variable extending throughout the general population, defined at the upper extreme by SAD. Research into population seasonality will require a dimensional measure of seasonal variation in mood and behavior that produces a broad, finely graded distribution of seasonality scores sensitive to individual differences throughout the entire range of scores. Accordingly, the Inventory of Seasonal Variation (ISV) was developed as such a measure. This study demonstrated that the ISV has high internal structural validity and is highly sensitive to individual differences in seasonality across its entire range of scores in the normal population. This latter characteristic is not shared by other existing measures of seasonality. Initial external validity of the ISV was supported in that the mean of ISV scores of a SAD sample was found to lie at the 97th percentile of the normal population of scores. Analysis of ISV scores revealed that a winter pattern of seasonality was reported by over 95% of subjects, a pattern that was more pronounced in women than men, while a summer type of seasonality was reported by only 0.6% of the general population.

Adult↗

PubMed1992

A model for the determination of the 3D-spatial distribution of the functions of the hormone-binding domain of receptors that bind 3-keto-4-ene steroids.

A method of comparing the hydrophobic clusters of proteins (hydrophobic cluster analysis, HCA) has revealed that the 3D-folding pattern of the hormone-binding domain (HBD) of steroid hormone receptors (SHRs) may have an unexpectedly high degree of analogy with the known 3D-crystal structures of proteins belonging to the serine proteinase inhibitor (SERPIN) superfamily, e.g. alpha 1-antitrypsin and ovalbumin. The present paper briefly reviews some of the biochemical evidence that supports the structural validity of the SERPIN model and shows how the model can be used to establish hypothetical 3D-locations for functions attributed to different amino-acids or peptide sequences of the HBD: i.e. heat-shock protein binding, transcription activation, phosphorylation, steroid binding, but also ATP-binding. Indeed, the model has enabled the identification of a Rossmann-fold in SHRs that might bind ATP. Visualization of all these functions should help to interpret the chain of concerted events induced by steroid binding.

Amino Acid Sequence↗

PubMed2026

Patient-reported outcome measures for depression or anxiety symptoms in patients with cardiovascular disease: A COSMIN systematic review.

BACKGROUND: Depression and anxiety are common in patients with cardiovascular disease (CVD), but the measurement quality of patient-reported outcome measures (PROMs) used in this population remains unclear. This review aimed to evaluate the methodological quality, measurement properties, and certainty of evidence for depression and anxiety PROMs in adults with CVD and to inform instrument selection. METHODS: Following COSMIN and PRISMA guidance, four databases were searched from inception to February 2026. Studies assessing measurement properties of PROMs in adults with CVD were included. Methodological quality was evaluated using the COSMIN Risk of Bias checklist, and certainty of evidence was graded using an adapted GRADE approach. RESULTS: Sixty-six studies assessing 38 PROMs were included, comprising 29 generic and 9 CVD-specific instruments. Six PROMs met COSMIN Category A criteria: Cardiac Depression Scale-Short Form, Patient Health Questionnaire-9, Beck Depression Inventory-II, Hospital Anxiety and Depression Scale, Generalized Anxiety Disorder-7, and Major Depression Inventory. Four instruments were classified as Category C because of insufficient structural validity. Content-validity evidence was largely indeterminate or of limited certainty. Only 24 studies used confirmatory factor analysis or Rasch analysis, and no study assessed measurement error or responsiveness. Cross-cultural validity evidence was scarce. CONCLUSIONS: Six PROMs met Category A criteria, but selection should remain purpose- and context-specific. Particular attention should be given to somatic symptom overlap and intended clinical use. Further validation should prioritize content validity, measurement invariance, responsiveness, measurement error, and clinimetric performance.

Humans↗

PubMed1991

Ice crystal damage and radiation effects in relation to microscopy and analysis at low temperatures.

There are several limitations to the low-temperature techniques which are currently being used for the preparation, examination and analysis of biological and organic samples by means of high-energy beam instrumentation. The low thermal conductivity of samples and the inadequacy of rapid cooling techniques means that, with the exception of thin-film suspensions and the surface of impact-cooled bulk specimens which may be vitrified, ice crystals of varying sizes will be present in nearly all samples which are quench cooled. Data are presented which indicate the depth to which adequate cryo-fixation may be achieved for both morphological and analytical studies. Although dynamic processes may be time resolved in the outer parts of quench-cooled samples, the decreased freezing rate below the surface makes resolution of these processes much less certain. The quality of information which may be obtained from quench-cooled samples is limited by radiation damage. Low-dose microscopy of vitrified thin-film suspensions of macromolecules continues to provide valid structural information at the molecular level. The increased doses needed for X-ray microanalysis present serious problems with the high spatial resolution analysis of thin frozen-hydrated sections although much less damage is observed in dried samples. A case is presented for using the outer fracture faces of frozen-hydrated bulk samples for low-resolution analysis of cells and tissues.

Electron Probe Microanalysis↗

PubMed1979

Identification of urinary and biliary metabolites of alprenolol in the rat.

1. After oral administration of alprenolol to rat, 12 metabolites were isolated and characterized as trifluoroacetyl, trimethylsilyl and n-butylboronate derivatives, using a g.l.c.-mass spectrometry-computer system. Fragmentation pathways of derivatives in the mass-spectrometric analysis are discussed. 2. Metabolic reactions involved are oxidative degradation of the propanolisopropylamine side-chain, aromatic hydroxylation, oxidation of the allyl group, and conjugation. A method for direct analysis of epoxide functions in the allyl group is described. 3. In comparison with metabolism of alprenolol in vitro, more polar metabolites are formed in vivo but the same principal metabolic pathways are valid. Structural features for biliary excretion are discussed.

Alprenolol↗

PubMed1991

Assessment of ambulatory blood pressure recorders: accuracy and clinical performance.

There are now more than ten different manufacturers of non-invasive, portable blood pressure monitors in North America, Europe, and Japan. These ambulatory blood pressure recorders measure blood pressure by either auscultatory or oscillometric methodology. Technologic advances in the recorders have resulted in reduction in monitor size, reduction in or absence of motor noise during cuff inflation, ability to program the recorder without an external computer system, and enhanced precision. Recently, there has been concern that more structured validation protocols have not been implemented prior to the widespread marking of ambulatory blood pressure recorders. There is a need for proper assessment of recorders prior to use in clinical research or practice. Data on several existing recorders suggest that while most are reasonably accurate during resting measurements, many lose this accuracy during motion, and clinical performance may vary among the monitors. Validation studies of ambulatory recorders should include comparison with mercury column and intra-arterial determinations, resting and motion measurements, and assessment of clinical performance in hypertensive patients.

Blood Pressure↗