Search

The social relations model is a statistical tool that allows the analysis of group dynamics as dyadic interactions between individuals. Within a multiple group structural equation modeling framework, Wald-tests and likelihood ratio tests based on (1) equality constraints among model parameters and (2) Lagrange multipliers for restrictions among non-linear parameter transformations are presented as methods for group-comparisons of various quantifications of group dynamics that hold different interpretations. The methods are illustrated with an empirical example. A simulation study investigates the performance of the methods with regard to Type I error-rate recoverability and statistical power and displays overall promising results. Implications and limitations are discussed. published

The present contribution provides a tutorial for the estimation of the social relations model (SRM) by means of structural equation modeling (SEM). In the overarching SEM-framework, the SRM without roles (with interchangeable dyads) is derived as a more restrictive form of the SRM with roles (with noninterchangeable dyads). Starting with the simplest type of the SRM for one latent construct assessed by one manifest round-robin indicator, we show how the model can be extended to multiple constructs each measured by multiple indicators. We illustrate a multiple constructs multiple indicators SEM SRM both with and without roles with simulated data and explain the parameter interpretations. We present how testing the substantial model assumptions can be disentangled from testing the interchangeability of dyads. Additionally, we point out modeling strategies that adhere to cases in which only some members of a group can be differentiated with regards to their roles (i.e., only some group members are noninterchangeable). In the online supplemental materials, we provide concrete examples of specific modeling problems and their implementation into statistical software (Mplus, lavaan, and OpenMx). Advantages, caveats, possible extensions, and limitations in comparison with alternative modeling options are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Adolescence is characterized by manifold changes on a biological, social, cognitive, and not least on an emotional level, which are accompanied by high intra-individual variability in emotional experience. Previous findings from educational research suggest that this intraindividual variability is also reflected in retrospection effects (i.e., recall bias) of adolescents’ emotional experience. According to the findings by Bieg, Goetz, and Lipnevich (2014), adolescent students (at the age of about 16 years) generally overestimated the emotional experience in retrospective assessments, i.e., intensity bias as a type of recall bias, in which both positive and negative emotional experience is overestimated in retrospect. In contrast, Venetz and Zurbriggen (2016) found that 12-year-old students retrospectively report higher levels of positive activation (PA) and lower levels of negative activation (NA) than in situ, pointing to a positive recall bias (i.e., “rosy view”). In a study by Zurbriggen, Jendryczko, and Nussbeck (in revision), however, students in adolescence (at the age of about 15 years) reported lower PA and higher NA in retrospect than in situ, thus referring to a negative recall bias (i.e., “blue view”). Furthermore, the findings indicated a negative shift in recall bias of students’ emotion s ince the beginning of early adolescence. Studies on predictors of recall bias in adulthood indicate that primarily personality traits (especially neuroticism and extraversion) as well as individual differences in emotional regulation affect recall bias of reports of emotional experience (Levine, Prohaska, Burgess, Rice, & Laulhere, 2001; Safer & Keuler, 2002; Safer, Levine, & Drapalski, 2002; Robinson & Clore, 2002a). Research has repeatedly demonstrated correlations between emotion regulation strategies and mental disorders in adolescence (e.g. Compas et al., 2017), an important developmental phase of life that is already associated with a considerable increase in psychological problems such as anxiety and depression as (pathological) forms of internalizing experience and behavior (e.g., Bertha & Balázs, 2013; Valois, Zullig, Huebner, & Drane, 2004). In consideration of these findings, the present follow-up study examines whether personality factors and internalizing experience and behavior could predict a recall bias in adolescent students' emotional experience.

With a wide range of available cytotoxic therapeutics, the main focus of current cancer research is to deliver them specifically to the cancer cells, minimizing toxicity against healthy tissues. Targeted therapy utilizes different carriers for cytotoxic drugs, combining a targeting molecule, typically an antibody, and a highly toxic payload. For the effective delivery of such cytotoxic conjugates, a molecular target on the cancer cell is required. Various proteins are exclusively or abundantly expressed in cancer cells, making them a possible target for drug carriers. Fibroblast growth factor receptor 1 (FGFR1) overexpression has been reported in different types of cancer, but no FGFR1-targeting cytotoxic conjugate has been approved for therapy so far. In this study, the FGFR1-targeting peptide previously described in the literature was reformatted into a peptibody-peptide fusion with the fragment crystallizable (Fc) domain of IgG1. PeptibodyC19 can be effectively internalized into FGFR1-overexpressing cells and does not induce cells' proliferation. The main challenge for its use as a cytotoxic conjugate is a cysteine residue located within the targeting peptide. A standard drug-conjugation strategy based on the maleimide-thiol reaction involves modification of cysteines within the Fc domain hinge region. Applied here, however, may easily result in the modification of the targeting peptide with the drug, limiting its affinity to the target and therefore the potential for specific drug delivery. To investigate if this is the case, we have performed conjugation reactions with different auristatin derivatives (PEGylated and unmodified) under various conditions. By controlling the reduction conditions and the type of cytotoxic payload, different numbers of cysteines were substituted, allowing us to avoid conjugating the drug to the targeting peptide, which could affect its binding to FGFR1. The optimized protocol with PEGylated auristatin yielded doubly substituted peptibodyC19, showing specific cytotoxicity toward the FGFR1-expressing lung cancer cells, with no effect on cells with low FGFR1 levels. Indeed, additional cysteine poses a risk of unwanted modification, but changes in the type of cytotoxic payload and reaction conditions allow the use of standard thiol-maleimide-based conjugation to achieve standard Fc hinge region cysteine modification, analogously to antibody-drug conjugates.

Changes in the quality of emotional experience are among the various significant developmental challenges that characterize early adolescence. Although retrospective and momentary emotional self-reports are known to differ, adolescents' emotional experiences are mainly assessed retrospectively without knowing if the recall is biased in a positive or negative way. The present study extends research on recall bias by investigating possible changes in retrospection effects of students' affective experiences during early adolescence. To this end, we compared retrospectively assessed affect with in situ reported affect. At the age of about 12 years (T1) and 3 years later (T2), 120 students repeatedly reported their momentary positive and negative affect during one school week and once in retrospective at the end of the school week. Furthermore, we examined whether students' emotional attitudes toward school have an effect on retrospection effects of students' affect and on change in retrospection effects from T1 to T2. To test our hypotheses, we applied multilevel first-order and second-order latent difference models. Results indicate a positive recall bias (i.e., rosy view) of students' reports of their positive and negative affect in the classroom at T1 and a negative shift in recall bias by T2. Furthermore, findings supported that a rosy view is less likely to occur, if a student is less emotionally involved in school. In turn, positive emotional attitudes toward school appear to serve as a buffer for the tendency toward a negative recall bias (i.e., blue view) at the end of early adolescence. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Targeted therapies are a promising alternative to conventional chemotherapy, with an increasing number of therapeutics targeting specific molecular aberrancies in cancer cells. One of the emerging targets for directed cancer treatments is fibroblast growth factor receptors (FGFRs), which are known to be involved in the pathogenesis and progression of multiple cancer types, specially in lung, bladder, and breast cancers. Here, we are demonstrating the development of the FGFR1-targeting agent based on the interactome screening approach, based on the isolation of binding regions from ligands interacting with the receptor. The parallel analysis by FGFR1 pull-down of chymotryptic peptides coupled with MS analysis, and PepSpot analysis yielded equivalent peptide sequences from FGF4, one of the FGFR1 ligands. Three sequences served as a basis for peptibody (Fc-fusion) generation, to overcome clinical limitations of peptidic agents, and two of them showed favorable FGFR1-binding in vitro and FGFR1-dependent internalization into cells. To validate if developed FGFR1-targeting peptibodies can be used for drug delivery, similar to the well-established concept of antibody–drug conjugates (ADCs), peptibodyF4_1 was successfully conjugated with monomethylauristatin E (MMAE), and has shown significant and specific toxicity toward FGFR1-expressing lung cancer cell lines, with nanomolar EC50 values. Essentially, the development of new effective FGFR1 binders that comprise the naturally occurring FGFR-recognition peptides and Fc region ensuring high plasma stability, and long bloodstream circulation is an interesting strategy expanding targeted anticancer agents’ portfolio. Furthermore, identifying peptides effectively binding the receptor from sequences of its ligands is not limited to FGFRs and is an approach versatile enough to be a basis for a new peptide/peptibodies development strategy.

Cancer is currently the second most common cause of death worldwide. The hallmark of cancer cells is the presence of specific marker proteins such as growth factor receptors on their surface. This feature enables development of highly selective therapeutics, the protein bioconjugates, composed of targeting proteins (antibodies or receptor ligands) connected to highly cytotoxic drugs by a specific linker. Due to very high affinity and selectivity of targeting proteins the bioconjugates recognize marker proteins on the cancer cells surface and utilize receptor-mediated endocytosis to reach the cell interior. Intracellular vesicular transport system ultimately delivers the bioconjugates to the lysosomes, where proteolysis separates free cytotoxic drugs from the proteinaceous core of the bioconjugates, triggering drug-dependent cancer cell death. Currently, there are several protein bioconjugates approved for cancer treatment and large number is under development or clinical trials. One of the main challenges in the generation of the bioconjugates is a site-specific attachment of the cytotoxic drug to the targeting protein. Recent years have brought a tremendous progress in the development of chemical and enzymatic strategies for protein modification with cytotoxic drugs. Here we present the detailed protocols for the site-specific incorporation of cytotoxic warheads into targeting proteins using a chemical method employing maleimide-thiol chemistry and an enzymatic approach that relies on sortase A-mediated ligation. We use engineered variant of fibroblast growth factor 2 and fragment crystallizable region of human immunoglobulin G as an exemplary targeting proteins and monomethyl auristatin E and methotrexate as model cytotoxic drugs. All the described strategies allow for highly efficient generation of biologically active cytotoxic conjugates of defined molecular architecture with potential for selective treatment of diverse cancers.

Fibroblast growth factor receptors (FGFRs) are emerging targets for directed cancer therapy. Presented here is a new FGFR1-targeting conjugate, the peptibodyF2, which employs peptibody, a fusion of peptide and the Fc fragment of human IgG as a selective targeting agent and drug carrier. Short peptide based on FGF2 sequence was used to construct a FGFR1-targeting peptibody. We have shown that this peptide ensures specific delivery of peptibodyF2 into FGFR1-expressing cells. In order to use peptibodyF2 as a delivery vehicle for cytotoxic drugs, we have conjugated it with MMAE, a drug widely used in antibody&ndash, drug conjugates for targeted therapy. Resulting conjugate shows high and specific cytotoxicity towards FGFR1-positive cells, i.e., squamous cell lung carcinoma NCI-H520, while remaining non-toxic for FGFR1-negative cells. Such peptibody&ndash, drug conjugate can serve as a basis for development of therapy for tumors with overexpressed or malfunctioning FGFRs.

An automatic item generator for figural memory test items called figumem was developed. It is available in R. A cognitive model allowed the generation of hypothetically parallel items within three difficulty levels determined by visual information load. In a pilot study, participants solved three items for each level of visual load. Within an item response theory approach, the Rasch Poisson counts model and modifications of it were fitted to the data. Results showed overall satisfying fit. Visual information load explained most of the variance in item difficulty. Differences in difficulty between items of the same family were comparatively low, displaying the utility of the item generator for the creation of parallel test forms. Implications, limitations, and suggestions for the use and extensions of figumem are discussed. published

Turner syndrome (TS) affects approximately one out of 2500 females. Previous research indicates that women with TS experience impairment in several psychosocial domains as well as in quality of life (QoL). Data, however, mainly focus on girls, whereas data on adult women is extremely scarce, inconsistent and mainly low in sample size. Separate analysis of adult women, however, is important since women face other challenges of TS than girls.We compared 301 women with TS aged 16-73 years (from 14 centres in six European countries) to healthy controls with regard to depression, anxiety, self-esteem, attention deficit/hyperactivity disorder (ADHD), autism, romantic relationships, social participation, amount of working hours and satisfaction with income as well as with regard to psychological, physical, environmental, social and global QoL. The influence of psychosocial well-being on the different QoL-domains was examined via multiple regression models.Women with TS showed impairments in all psychosocial variables (anxiety, depression, ADHD, autism, self-esteem, social participation all p 0.001) except for the amount of working hours (p = 0.062) and satisfaction with income (p = 0.369). They also showed lower social (p 0.001), psychological (p 0.001) and physical QoL (p 0.001) compared to controls. Depression, satisfaction with income and self-esteem could be shown to be the best predictors for QoL.In conclusion, quality of life in TS is impaired, in particular it seems to be negatively affected by depression and low self-esteem whereas satisfaction with income has a positive influence. These results implicate that medical staff needs to pay attention on possible psychosocial impairments when treating women with TS. Strengthening self-esteem and counteracting depression potentially raises their QoL.

When a cognitive ability is assessed repeatedly, test scores and ability estimates are often observed to increase across test sessions. This phenomenon is known as the retest (or practice) effect. One explanation for retest effects is that situational test anxiety interferes with a testee&rsquo, s performance during earlier test sessions, thereby creating systematic measurement bias on the test items (interference hypothesis). Yet, the influence of anxiety diminishes with test repetitions. This explanation is controversial, since the presence of measurement bias during earlier measurement occasions cannot always be confirmed. It is argued that people from the lower end of the ability spectrum become aware of their deficits in test situations and therefore report higher anxiety (deficit hypothesis). In 2014, a structural equation model was proposed that specifically allows the comparison of these two hypotheses with regard to explanatory power for the negative anxiety&ndash, ability correlation found in cross-sectional assessments. We extended this model for usage in longitudinal studies to investigate the impact of test anxiety on test performance and on retest effects. A latent neighbor-change growth curve was implemented into the model that enables an estimation of retest effects between all pairs of successive test sessions. Systematic restrictions on model parameters allow testing the hypothetical reduction in anxiety interference over the test sessions, which can be compared to retest effect sizes. In an empirical study with seven measurement occasions, we found that a substantial reduction in interference upon the second test session was associated with the largest retest effect in a figural matrices test, which served as a proxy measure for general intelligence. However, smaller retest effects occurred up to the fourth test administration, whereas evidence for anxiety-induced measurement bias was only produced for the first two test sessions. Anxiety and ability were not negatively correlated at any time when the interference effects were controlled for. Implications, limitations, and suggestions for future research are discussed.

The paper reviews the formal action taken by the Silesian Medical University (SMU) in Katowice, against a professor who mass-produced plagiarized papers over many years. Plagiarized publications were based on articles of other authors, published in the European and American medical journals. Over 40 papers written by Andrzej Jendryczko, PhD, a former professor of biochemistry at SMU were declared to be plagiarized. Most of these publications have been retracted from Polish and international medical databases (Medline) by the editors of the journals involved. Dr. Jendryczko resigned in March 1998 from the Czestochowa Polytechnic, where he was a professor and Deputy Director of the Institute. Disciplinary action against him has still not been taken, because he is on sick leave. Criticizing some formal steps taken by SMU, the author proposes to establish a national committee for scientific misconduct. This independent committee, should be able by law to supervise the investigation in all Polish cases in academia which are suspected of scientific fraud. The committee also should have the power to initiate and conduct the investigation.

The group of 24 women in the course of the first pregnancy complicated by hypertension was investigated. The higher amount of cholesterol in red cells membrane was found comparing to healthy pregnant and nonpregnant women. Cholesterol amount in red cells membranes is related to LDL cholesterolemia.

The authors analyzed the concentration of malonic dialdehyde (MDA) in the cerebrospinal fluid (CSF) of children with intracranial hypertension. For the control group an intracranial pressure (ICP) of 250 mm H2O was taken as a reference point. The concentration of MDA was determined by a method using thiobarbituric acid. In a group of children with ICP values greater than the limiting value, the concentration of malonic dialdehyde was 0.629 mmol/mg protein, while in the control group with an ICP below 250 mm H2O, this value was 0.610 mmol/mg protein. The differences between the two groups were not statistically significant, from the results obtained it can be concluded that the concentration of MDA, as an isolated parameter, does not constitute a good measure of intensity of the lipid peroxidation processes in central nervous system (CNS) tissues, taken as an indicator of their disintegration in cases of hydrocephalus with intracranial hypertension.

The findings of many authors show that reduced fetal growth is followed by increased mortality from cardiovascular disease in adult life. They are further evidence that cardiovascular disease originates, among other risk factors, through programming of the bodies structure and metabolism during fetal and early post-natal life. Wrong maternal nutrition may have an important influence on programming.

Thirty two pregnancies with pregnancy-induced hypertension (PIH) and twenty seven control normal pregnancies were analysed with regard to maternal and fetal blood enzymatic antioxidants. In PIH maternal erythrocyte, platelet and serum blood and in umbilical cord blood levels of lipid peroxides were higher than in normal pregnancy. Also the activities of platelet and erythrocyte superoxide dismutase and glutathione peroxidase were lower in PIH women. The concentration of lipid peroxides was higher, and the activity of glutathione peroxidase were lower in umbilical cord elements of women with PIH, than corresponding values of women with normal pregnancy. We suggest that disturbances in antioxidant enzymatic system are involved in the pathogenesis of maternal PIH, and it may also have effects on the function of antioxidant status of the fetus.

42 patients between 21 and 63 years of age with chronic renal failure (CRF) treated with haemodialysis and 16 healthy subjects between 19 and 72 years of age were observed. All patients were divided in two groups: 15 patients treated with haemodialysis with cuprophan dialyser used first time and 27 patients treated with haemodialysis with cuprophan dialyser used more than three times. The blood samples in haemodialyzed patients were withdrawn four times: just before dialysis, during haemodialysis (after one hour of dialysis at both ends of the dialyzer) and after haemodialysis. Chromium and cadmium concentration in all examined groups, in dialysis fluid and in demineralized water were measured by flame atomic absorption spectrophotometry. During haemodialysis a decrease of serum chromium concentration and an increase of serum cadmium concentration in two groups of haemodialyzed patients were observed. No significant differences in serum chromium and cadmium concentration before dialysis, during dialysis and after dialysis were observed between two groups of haemodialyzed patients.The multiple use of cuprophan dialser did not influence significantly serum chromium and cadmium concentration in haemodialyzed patients.

In uraemic patients disturbances in carnitine metabolism are observed. Aim of the study was to assess total carnitine level in haemodialyzed patients and influence of dialyzer type on this level before, during and after haemodialysis (HD). We examined 46 patients divided into 3 groups: I--16 non-diabetic uraemic patients haemodialyzed using polysulfone dialyzer; II--10 diabetic patients haemodialyzed using polysulfone dialyzer, III--20 non-diabetic uraemic patients haemodialyzed with cuprophane dialyzer. Total plasma carnitine level was estimated using colorimetric method according to Wieland et al. Total carnitine level in diabetic haemodialyzed patients was significantly lower comparing to non-diabetic ones but in both groups a significant decrease during HD was present. Dialyzer type had no influence on carnitine elimination.

The purpose of the present work was to assess the relationship of leukocyte and erythrocyte superoxide dismutase activity to its cofactors concentrations i.e. zinc and copper in plasma and erythrocyte in diabetic patients and treatment variability. 104 patients were included in the study. 23 persons were in the control group. All patients were divided into 2 groups (NIDDM and IDDM). Patients with NIDDM were divided into 3 subgroups depending on treatment (insulin, gliclazide, dietary treated). In all groups, there were assessed following parameters: the leucocyte and erythrocyte SOD activity according to the method of Misra and Fridovich, and zinc and copper concentrations in plasma and erythrocyte, which were measured by flame absorption spectrophotometry. Statistical analysis was performed using the CRISP program.1. The leukocyte and erythrocyte superoxide dismutase activity is significantly lowered in diabetes mellitus. 2. In diabetic patients both in type I and type II as in the healthy people, there is a close correlation between SOD activity and its cofactors i.e. zinc and copper erythrocyte concentrations. 3. Insulin and gliclazide treatment increases SOD activity and delays late diabetic complications.

The authors of the study correlate malonic dialdehyde (MDA) concentration in the cerebrospinal fluid of infants with hydrocephalus with the values of intracranial pressure. The purpose of the study was verification of the usefulness of MDA concentration determination as an indicator of the processes of lipid peroxidation in CNS tissues in hydrocephalic children. The obtained results point out that the isolated MDA concentration is not a sufficiently precise marker of intracranial hypertension.

Levels of mineral elements (F, Na, Mg, Al, S, Cl, K, Ca, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Br, Rb, Mo, Cd, J, Ba, Hg and Pb), the role of which is well known and documented, were studied in 365 placentas. The significant negative correlations were ascertained between the content of Pb, Cd, F, Hg and the birth weight; the positive correlations were ascertained between some minerals (Mg, Ca, Co, Cu, Zn, Se) that are indispensable for the proper organism functioning and the fetus development.