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PubMed2007

Analysis of the inflammatory response in endovascular treatment of aortic aneurysms.

OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis.

Adult↗

PubMed1997

Identification of a motif within the 5' regulatory region of pS2 which is responsible for AP-1 binding and TCDD-mediated suppression.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds modulate several endocrine systems by altering hormone synthesis, enhancing ligand metabolism, and down-regulating receptor levels/binding activity. Previous studies have demonstrated that TCDD inhibits the 17beta-estradiol (E2)-induction of pS2, a human breast cancer prognostic marker. This inhibition occurs at the gene expression level and is Ah receptor (AhR)-mediated. Analysis of the 5' regulatory region has identified three motifs which resemble dioxin response element (DRE) core sequences. pS2-regulated luciferase deletion constructs identified the DRE-like motif located at -527 to -514 as being required for TCDD-mediated suppression. A point mutation within this core motif (T-518C) abolished the inhibition by TCDD while UV-induced protein-DNA cross-linking and competitive gel retardation assays demonstrated AhR complex binding to this motif. Further study of this region also revealed an adjacent putative AP-1 site, diverging by one base pair from the consensus sequence. Gel retardation assays using TPA-treated MCF-7 cell nuclear extracts showed an induced complex binding to the AP-1-like site. Competition studies and antibody supershifts confirmed that the retarded complex consists of AP-1-like proteins. pS2-regulated luciferase constructs containing mutations specific to the AP-1-like motif greatly diminished the inducibility in response to E2. These results suggest that an interaction between AhR complexes and AP-1-like proteins may be responsible for TCDD-mediated inhibition of E2-induced pS2 expression.

Base Sequence↗

PubMed2025

Integration of multiple omics reveals key targets and cellular mechanisms for intervention in sarcopenia.

BACKGROUND: Sarcopenia, an age-related syndrome characterized by progressive loss of muscle mass, strength, and function, presents a significant global health burden with limited therapeutic interventions. This study integrates genomic causality, multi-tissue omics, and cellular mediation analyses to identify and prioritize mechanistically grounded therapeutic targets. METHODS: A multi-tiered analytical framework was applied, beginning with two-sample Mendelian randomization (MR) to infer causal relationships between 4907 plasma proteins (cis-pQTLs from 35,559 individuals) and sarcopenia traits in Pan-UK Biobank participants. Bayesian colocalization and transcriptomic validation in human sarcopenia muscle biopsies were employed to prioritize targets. Cellular mediation analysis quantified contributions of immune and stromal cell subtypes to protein-trait pathways using transcriptomic deconvolution. RESULTS: MR identified 1237 plasma proteins causally associated with sarcopenia traits, with six targets (HGFAC, GATM, HMOX2, F2, LMAN2L, HPGDS) validated through colocalization, transcriptomic expression, and sarcopenia-related dysregulation. Cellular mediation revealed immune mechanisms underlying HGFAC's effects, with CD4+ regulatory T cells mediating 3.49 % of its impact on sarcopenia traits. Prothrombin exhibited muscle-protective effects independent of coagulation. CONCLUSION: This study establishes a causal map linking plasma proteins to sarcopenia through immune-stromal interactions. The integration of MR, multi-omics validation, and cellular mediation prioritizes six proteins as actionable targets, supporting repurposing of thrombin inhibitors and development of immunometabolic therapies. The framework bridges genomic causality with cellular pathophysiology, advancing precision strategies for age-related muscle decline.

Humans↗

PubMed2026

DNA Methylation, SERPING1 Expression, and Immune-related Traits in Osteoporosis: A Mendelian Randomization Study And Supportive Ex Vivo Evidence.

INTRODUCTION: Osteoporosis (OP) is a major public health burden; however, the role of SERPIN family proteins remains incompletely understood. This study aimed to investigate genetically inferred associations between SERPINs and OP and to explore potential regulatory relationships. METHODS: Genome-wide association study (GWAS) summary statistics were used to perform two-sample Mendelian randomization (MR) and summary-data-based Mendelian randomization (SMR) analyses. Primary MR estimates were derived using inverse-variance-weighted (IVW), MR-Egger, weighted median, simple mode, and weighted mode methods. Cancellous bone tissue from the greater trochanter of the femur was collected from three patients with OP and three non-osteoporotic controls. qPCR and WB were used to analyze the whole bone homogenate, IHC was used to detect decalcified bone sections, and mediation analysis was used to explore potential regulatory associations. RESULTS: Among the proteins of the SERPIN family, only SERPING1 had an obvious positive correlation with the risk of osteoporosis (OR = 1.06, P = 0.0012). qPCR, WB, and IHC analyses demonstrated increased SERPING1 mRNA and protein expression in bone tissue from OP patients. Mediation analyses suggested that cg15918732 DNA methylation may serve as an upstream regulatory factor for SERPING1 expression. In addition, the downstream associations also consist of the alteration of immune cell conditions, like the decrease in the quantity of natural killer cells and T cells, and the rise in the level of mononuclear cells, and so forth. DISCUSSION: These findings provide genetic evidence for the possible role of SERPING1 in OP, which may be achieved through epigenetic regulation and immune pathways. Due to the corresponding characteristics of genetic inference and the small sample size, these results are hypothetical and generative. CONCLUSION: This study shows that DNA methylation of cg15918732 may be associated with SERPING1 expression in osteoporosis and immune-related traits. These findings provide new insights into potential epigenetic and immunological pathways in osteoporosis, which may contribute to future mechanistic and translational research.

Humans↗

PubMed2026

To unveil the causal relationship between immunophenotypes and colorectal cancer using two-sample bidirectional Mendelian randomization and mediation analyses.

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide. The mechanisms underlying this trend are not yet fully understood. This study aimed to examine the potential role of genetically predicted immunophenotypes in the development of CRC. A two-sample bidirectional Mendelian randomization study was conducted to explore the relationship between 731 genetically predicted immune cells and CRC. Furthermore, a two-step Mendelian randomization approach was employed to assess the possible mediating effect of immune cells on CRC. The inverse-variance weighted method identified 5 immunophenotypes as significantly inversely associated with CRC risk: the odds ratios for CRC risk associated with activated CD4 regulatory T cells (%CD4 regulatory T cells), CD25++ CD45RA- CD4 nonregulatory T cells (%CD4 + T cells), CD25++ CD45RA- CD4 nonregulatory T cells (%T cells), CD25++ CD8 + T cells (%T cells), and CD64 + CD16 + monocytes were 0.925 (95% CI = 0.874-0.978, P = 6.516 × 10-3), 0.935 (95% CI = 0.878-0.995, P = .035), 0.936 (95% CI = 0.889-0.985, P = .011), 0.863 (95% CI = 0.786-0.948, P = 2.142 × 10-3), and 0.636 (95% CI = 0.519-0.778, P = 1.18 × 10-5), respectively. The mediation analysis indicated that the absolute count of CD25++ CD8 + T cells led to a 33.9% decrease in the risk associated with the percentage of activated CD4 regulatory T cells within CD4 regulatory T cells and CRC. Our analysis revealed that 5 immunophenotypes may be risk factors for CRC. Since other complementary methods have yielded inconsistent results, however, further investigation is necessary.

Colorectal Neoplasms↗

PubMed2026

Life-course influence of birthweight and subsequent pathways on healthy aging: a Mendelian randomization study.

BACKGROUND: Birthweight readily measurable marker of fetal growth that may influence health across the lifespan. We aimed to investigate the potential causal association between birthweight and healthy aging and to identify the mediating roles of subsequent socioeconomic, behavioral, functional, and disease-related factors to inform life-course strategies to promote healthy aging and reduce health inequities. METHODS: We performed two-sample Mendelian randomization analyses in European-ancestry participants to estimate the effect of birthweight (n = 298,142-423,683) on two robust, composite healthy aging phenotypes (genetically independent phenotype of aging (aging-GIP) and multivariate aging-related genetic factor (mvAge)) and six individual aging phenotypes, including healthspan, resilience, parental lifespan, self-rated health, phenotypic age deceleration, and 90th percentile self-longevity (n = 34,710-1,958,774), and screened for 100 candidate mediators (n = 14,267-1,812,017) using a two-step mediation analysis. RESULTS: Genetically determined each 1-SD higher birthweight was associated with higher aging-GIP (β [95% CI] in different models ranging from 0.131 [0.066-0.196] to 0.162 [0.089-0.235] SDs) and mvAge (0.036 [0.010-0.063] to 0.045 [0.024-0.067]), independent of later-life obesity indicators; also with more interpretable benefits, including 12%-16% higher odds of longer healthspan, a 0.079-0.089 SD improvement in resilience, and a 1.22-1.74 year increase in parental lifespan. Of 100 candidates, 26 and 25 mediated the effect of birthweight on aging-GIP and mvAge, respectively, including socioeconomic indicators (education, household income, occupational attainment; individual mediation proportion: 12.72%-27.79%); behaviors (e.g., cheese intake, age at first sex; 10.38%-29.56%); physical functions (e.g., blood pressure, grip strength; 7.57%-42.65%); and cardiometabolic diseases (e.g., type 2 diabetes, cardiovascular diseases; 25.02%-70.11%). CONCLUSIONS: Higher birthweight within the normal range directly promotes healthy aging, mediated by multifaceted modifiable factors. Our findings advocate adopting a life-course approach to foster healthy aging, starting with optimal birthweight and extending to interventions that enhance socioeconomic status, promote healthy behaviors, strengthen physical functions, and prevent cardiometabolic diseases.

Mendelian Randomization Analysis↗

PubMed2026

Biological Mechanisms Underlying the Cardiovascular Effects of Branched-Chain Amino Acids: A Proteome-Wide Mendelian Randomization Study.

BACKGROUND: Ischemic heart disease (IHD) is the leading cause of morbidity and mortality. Branched-chain amino acids (BCAAs) are associated with higher IHD risk, but the underlying biological pathways remain unclear. OBJECTIVES: This study aims to explore these pathways using 2-step proteome-wide Mendelian randomization. METHODS: We examined the associations between genetic proxies for BCAAs and 2922 proteins in the United Kingdom Biobank Pharma Proteomics Project, supplemented by a meta-analysis with data from deCODE to identify proteins associated with BCAAs. Next, we tested their effects on IHD risk using Coronary Artery Disease Genome-wide Replication and Meta-analysis plus Coronary Artery Disease Genetics Consortium (122,733 cases and 424,528 controls) and replicated in FinnGen (31,640 cases and 187,152 controls). We conducted sensitivity analyses using genetic instruments from deCODE. Proteins associated with IHD risk and, in a consistent direction, with genetically predicted BCAAs were considered potential mediators. RESULTS: Genetic proxies for BCAAs were associated with 40 proteins. Among these, 6 proteins showed consistent evidence of mediation, including complement C1s subcomponent, coagulation factor II, granulin, proprotein convertase subtilisin/kexin type 9, sex hormone-binding globulin, and V-set and transmembrane domain-containing protein 2-like. These proteins are involved in inflammation, coagulation, lipid metabolism, and cellular stress response. All associations were robust across different analytical methods and replicated in independent datasets. Mediation analysis showed that these proteins accounted for 6.5% to 32.1% of the association between BCAAs and IHD risk. CONCLUSIONS: This study identified 6 proteins that potentially link BCAAs to IHD, implicating pathways related to inflammation, coagulation, lipid metabolism, and cellular stress responses. To our knowledge, these findings provide novel mechanistic insights into the BCAA-IHD relationship and highlight potential protein targets for future prevention and intervention strategies.

Amino Acids, Branched-Chain↗

PubMed2002

Motivations that maintain substance use among individuals with psychotic disorders.

This study quantitatively examined reasons for substance use among individuals with psychotic disorders and explored the relationship of these reasons to substance use problems and dependence. Sixty-nine people with psychotic disorders were interviewed using a battery of questionnaires called the Substance Use Scale for Psychosis (SUSP). Symptoms and medication side effects were also measured. A factor analysis revealed similar motives for substance use (mostly alcohol and cannabis use) as in the general population: "enhancement," "social motives," "coping with unpleasant affect," and "conformity and acceptance." A fifth factor, "relief of positive symptoms and side effects," demonstrated limited reliability. "Coping" and "enhancement" motives were found to lead to substance use problems and dependence. Mediator analysis indicated that worse symptoms lead to stronger motives for substance use, which in turn lead to stronger psychological dependence on that substance. These findings have the potential to inform effective treatment for substance use in psychosis.

Adaptation, Psychological↗

PubMed2026

Branching plasticity and candidate gene-hormone networks associated with shade responses in soybean under relay strip intercropping.

BACKGROUND: Branching is a key determinant of high-yield plant architecture in soybean, particularly in maize- soybean relay strip intercropping where plants experience an "initially shaded-then fully illuminated" light regime. However, the genetic regulation of branching responses to shading remains poorly understood. METHODS: We evaluated 11 branching-related traits across 202 soybean accessions grown under monoculture (SS) and relay strip intercropping (RI). Branch number (BN), branching incidence (BI), and total branch length (TBL) were assessed together with stress tolerance indices (STI) and relative distance plasticity index (RDPI). Genome-wide association studies (GWAS) using mixed linear model (MLM) and three-variance-component MLM (3VmrMLM) were combined with haplotype and protein structural analyses to refine candidate genes. RESULTS: Based on Pearson correlation analysis of all 11 traits, BN, BI, and TBL measured before maize harvest showed the strongest and most consistent associations with branch seed weight within the corresponding cropping system (BSW_SS under SS and BSW_RI under RI), whereas other traits showed weaker or environment-dependent associations. Higher STI values calculated from these traits during the co-growth phase were negatively associated with BSW_RI, suggesting weaker compensatory recovery after light restoration in genotypes with more stable early branching patterns between SS and RI. In contrast, mediation analysis indicated that RDPI was positively associated with BSW_RI mainly through improved mature branching architecture (MB_index), which accounted for approximately 70% of the total positive effect. GWAS identified 57 and 74 significant QTNs using MLM and 3VmrMLM, respectively, and LD-window genes were filtered for exonic nonsynonymous or premature stop-codon variants, yielding 883 genes with putative functional variants. Two high-confidence genes emerged: Glyma.02G058600 (PP2C55), exhibiting shading-specific haplotype effects likely linked to GA-mediated branch-stem balance, and Glyma.02G059900 (DA1-related protein), showing stable effects across environments and implicated in ABA-mediated suppression of axillary meristems. CONCLUSIONS: These results provide insight into the genetic and physiological basis of soybean branching responses under relay strip intercropping, clarify that branching plasticity and relative shade tolerance represent distinct response dimensions in this system, and identify putative loci that may be useful for breeding soybean cultivars with improved shade adaptation and yield stability.

Glycine max↗

PubMed2006

Minority stress and sexual problems among African-American gay and bisexual men.

Minority stress, such as racism and gay bashing, may be associated with sexual problems, but this notion has not been examined in the literature. African-American gay/bisexual men face a unique challenge in managing a double minority status, putting them at high risk for stress and sexual problems. This investigation examined ten predictors of sexual problems among 174 African-American gay/bisexual men. Covarying for age, a forward multiple regression analysis showed that the measures of self-esteem, male gender role stress, HIV prevention self-efficacy, and lifetime experiences with racial discrimination significantly added to the prediction of sexual problems. Gay bashing, psychiatric symptoms, low life satisfaction, and low social support were significantly correlated with sexual problems, but did not add to the prediction of sexual problems in the regression analysis. Mediation analyses showed that stress predicted psychiatric symptoms, which then predicted sexual problems. Sexual problems were not significantly related to HIV status, racial/ethnic identity, or gay identity. The findings from this study showed a relationship between experiences with racial and sexual discrimination and sexual problems while also providing support for mediation to illustrate how stress might cause sexual problems. Addressing minority stress in therapy may help minimize and treat sexual difficulties among minority gay/bisexual men.

Adult↗

PubMed2005

Pharmacodynamic analysis of target inhibition and endothelial cell death in tumors treated with the vascular endothelial growth factor receptor antagonists SU5416 or SU6668.

PURPOSE: To determine the effects of small molecule inhibitors of vascular endothelial growth factor receptor (VEGFR)-2 (SU5416 and SU6668) on receptor phosphorylation in tumor xenografts and in paired tumor biopsies obtained in three clinical trials in patients with advanced solid malignancies. EXPERIMENTAL DESIGN: The dose-dependent effects of SU6668 on angiogenesis and tumor growth were investigated in orthotopic L3.6pl pancreatic tumors. Excisional or 18G core biopsies were obtained from patients before and after therapy with SU5416 or SU6668. Laser scanning cytometry-mediated analysis was used to quantify levels of phosphorylated and total VEGFRs and platelet-derived growth factor receptors (PDGFR), tumor microvessel densities, vessel sizes, and endothelial and tumor cell apoptosis. RESULTS: Significant inhibition of tumor microvessel density and growth and increased apoptosis were observed at SU6668 maximum tolerated dose (100 mg/kg) in L3.6pl xenografts. At 6 hours post therapy, SU6668 reduced VEGFR and PDGFR phosphorylation in the tumors by 50% and 92%, respectively, but levels rebounded beyond the baselines by 24 hours. Levels of phosphorylated VEGFR-2 and PDGFR also decreased significantly ( approximately 50%) 6 hours after therapy in 1 of 6 primary human tumors treated with SU6668, but these effects were not associated with increased apoptosis. A significant increase in endothelial cell apoptosis was observed in one tumor exposed to SU5416 and was associated with an increase in vessel size, but these changes occurred without an increase in tumor cell death. CONCLUSIONS: SU5416 and SU6668 displayed biological activity in xenografts. However, neither drug produced marked biological activity in primary patient tumors.

Adult↗

PubMed2026

The role of psychological resilience in the relationship between complex post-traumatic stress disorder symptom severity and functioning impairment in mental health support-seeking Australian defence force veterans: A cross-sectional study.

OBJECTIVE: Military veterans have high rates of mental health conditions; complex post-traumatic stress disorder may be the most functionally impaired trauma diagnosis in this patient group. Psychological resilience acts as a protective factor for mental health. Still, it is unclear how this may influence relationships between the two main symptom clusters of complex post-traumatic stress disorder and functioning impairment in veterans. Therefore, we investigated the relationships between psychological resilience, trauma symptom severity, trauma exposure and work/social functional impairment among Australian Defence Force veterans. METHODS: Cross-sectional survey including 148 mental health support-seeking former-serving Australian Defence Force veterans in primary care. Relationships between variables were explored using correlations, mean difference tests and mediation analysis to examine the role of resilience in the relationship between complex post-traumatic stress disorder symptoms and functional impairment. RESULTS: Resilience showed significant negative correlations with functioning impairment. The number of traumas showed weak positive correlations with disturbances in self-organisation symptoms, post-traumatic stress disorder symptoms and functional impairment. The complex post-traumatic stress disorder group had significantly lower resilience and functioning than those with no diagnosis. After controlling for the number of trauma exposures, resilience partially mediated the association between post-traumatic stress disorder symptoms and functioning (indirect effect = 0.141, p < 0.05), and partially mediated the association between disturbances in self-organisation symptoms and functioning (indirect effect = 0.157, p < 0.05). CONCLUSIONS: Psychological resilience was associated with better functioning in veterans regardless of trauma diagnosis. Resilience also partially mediates the relationship between disturbances in self-organisation/post-traumatic stress disorder symptoms and functioning in those with International Classification of Diseases, 11th Revision, complex post-traumatic stress disorder, indicating it is an important intervention target in Australian Defence Force veterans with polytrauma.

Humans↗

PubMed2026

Causal Associations and Potential Mediating Factors between Sarcopenia-Related Traits and Heart Failure Risk: A Mendelian Randomization Study.

INTRODUCTION: In this two-sample, two-step Mendelian randomization (MR) study, we aimed to elucidate the causal associations between sarcopenia-related characteristics and heart failure (HF) risk, and to identify the factors mediating these associations, with a particular focus on the mediating roles of obesity and sedentary habits. METHODS: Genetic instruments for appendicular lean mass (ALM), hand grip strength (HGS), walking pace (WP), and potential mediators were extracted from genome-wide association studies. Inverse-variance weighting (IVW) was used as the primary analytical method, supplemented by MR-Egger regression, weighted median, and weighted mode analyses. Sensitivity analyses including Cochran's Q test and MR-Egger intercept method were performed to assess heterogeneity and pleiotropy. Bidirectional MR was conducted to exclude reverse causation. RESULTS: IVW revealed that a faster genetically predicted WP was associated with lower HF risk (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.33-0.60, p = 5.806 × 10-7). The mediation analysis indicated that body mass index (BMI) accounted for 32% of this effect, while time spent watching television accounted for 14%. Elevated ALM showed a slight but significant positive association with HF risk (OR 1.06, 95% CI 1.03-1.09, p = 5.437 × 10-4). However, multivariable MR adjusting for BMI completely attenuated this association (p = 0.693), suggesting ALM reflects overall body composition rather than isolated muscle mass. No significant associations were found between HGS and HF. Bidirectional MR showed no robust reverse effects. CONCLUSIONS: These findings suggest that genetically predicted increased WP exerts beneficial effects against HF, partially mediated by obesity and sedentary habits. Targeting weight management and anti-sedentary interventions may mitigate HF risk in individuals with sarcopenia-related characteristics.

Heart failure↗

PubMed2026

Maternal prior pregnancy outcome subtype and offspring cryptorchidism: A retrospective case-control study.

OBJECTIVE: To determine whether maternal prior pregnancy outcome subtype and frequency are associated with cryptorchidism in male offspring, and whether first-trimester exogenous progesterone exposure mediates any observed association. MATERIALS AND METHODS: We conducted a hospital-based retrospective case-control study of 1220 mother-son pairs (610 cryptorchidism cases; 610 controls). Maternal prior pregnancy outcome subtype was defined using a prespecified proximal-event approach based on the most recent qualifying pregnancy event before the index pregnancy: no prior pregnancy loss or termination, miscarriage, or pregnancy termination. Subtype-specific frequency was categorized as 0, 1, or ≥2. Adjusted odds ratios (aORs) were estimated using multivariable logistic regression; robustness was examined using 1:1 propensity score matching with conditional logistic regression. Exploratory mediation analysis estimated indirect effects through first-trimester exogenous progesterone exposure. RESULTS: In fully adjusted models, miscarriage was associated with higher odds of cryptorchidism compared with no prior pregnancy loss or termination (aOR 1.97; 95% CI 1.26-3.09), whereas pregnancy termination was not (aOR 1.14; 95% CI 0.86-1.52). In joint subtype-frequency analyses, odds increased with the number of miscarriages (one: aOR 1.74; 95% CI 1.07-2.83; two or more: aOR 3.77; 95% CI 1.22-11.66) and were higher for two or more pregnancy terminations (aOR 1.77; 95% CI 1.10-2.84). Matched analyses were directionally consistent. Mediation analyses suggested a modest indirect effect through first-trimester progesterone exposure for the miscarriage association. CONCLUSIONS: Maternal prior miscarriage was associated with cryptorchidism in male offspring, whereas pregnancy termination showed higher odds only among women with two or more prior procedures. First-trimester exogenous progesterone exposure may account for a modest proportion of the miscarriage-cryptorchidism association.

Humans↗

PubMed2025

Genome-wide association study of angiotensinogen levels and key single nucleotide polymorphism associations with blood pressure.

OBJECTIVE: The renin angiotensin aldosterone system plays a key role in circulatory homeostasis. We sought to identify genetic determinants of measured plasma angiotensinogen levels and subsequently evaluate the association of these single nucleotide polymorphisms (SNPs) with blood pressure (BP) and hypertension in a multiethnic population. METHODS: Genome-wide association study (GWAS) of plasma angiotensinogen levels, measured using an enzyme-linked immunoassay, was conducted in 4899 Multi-Ethnic Study of Atherosclerosis (MESA) participants (self-identified as White, n = 1865; Hispanic, n  = 1113; Black, n  = 1224; and Chinese, n  = 629). Linear and logistic models examined the association between SNPs with angiotensinogen and hypertension, respectively. Mediation analysis evaluated the effect of angiotensinogen on BP/hypertension through the top SNPs identified by GWAS. RESULTS: In the analysis utilizing all participants, 115 SNPs were associated with angiotensinogen ( P  < 5 × 10 -8 ), including lead SNP rs4762(G>A) in exon 2 ( P  = 1.51E -100 ) and rs5050(T>G) in the promoter region ( P  = 2.26E -69 ) of the AGT gene. Race/ethnic-specific analyses identified rs4762(G>A) as the lead SNP for White and Hispanic participants, whereas Black and Chinese participants had rs5050(T>G) and rs16852311(G>C), respectively. Both rs4762(G>A) and rs5050(T>G) indirectly increased systolic BP, diastolic BP, and the odds of hypertension through its effect of increasing angiotensinogen. CONCLUSIONS: Our findings demonstrate racial/ethnic differences in genetic effects on angiotensinogen levels across multiple SNPs. AGT rs4762(G>A) and rs5050(T>G) impact BP and hypertension through a mediated effect via angiotensinogen, though opposing direct effects may mask the overall association.

Humans↗

PubMed2002

Performance on measures of executive function following pediatric traumatic brain injury.

OBJECTIVE: To investigate the relationships among age at injury, neuroanatomic lesion location, and measures of executive function (EF) following paediatric traumatic brain injury (TBI). METHODS: EF was assessed in 68 children (aged 7-15) with moderate-to-severe TBI 1 year post-injury. EF tests included: (1) Tower of Hanoi (TOH), a measure of problem solving ability, (2) Wisconsin Card Sorting Test (WCST), a measure of categorization and ability to shift cognitive strategies, (3) Letter Fluency (LF), a measure of novel lexical search and rule-governed word generation. EF variables included number of moves needed to achieve a 3-ring solution on the TOH, number of perseverative and non-perseverative errors on the WCST, and number of words generated on LF. Intellectual functioning was also assessed using the Verbal Intellectual Quotient (VIQ) from the Wechsler Intelligence Scale from Children-3rd edn (WISC-III). Data from standardized MRIs, performed at 3-months post-injury, were available for all subjects and were used to determine lesion location, lesion volumes, and total number of lesions. The relationships among EF, lesion variables (frontal lesion volume, extrafrontal lesion volume, total number of lesions) and age at injury were examined. Pre-injury special education services and attention deficit hyperactivity disorder (ADHD) were controlled for. RESULTS: Younger age at injury was associated with more perseverative errors on the WCST and worse performance on LF. Frontal lesion volume was not predictive of performance on any measures of EF. Greater extrafrontal lesion volume and total number of lesions were predictive of worse performance on LF. When controlling for pre-injury special education placement and pre-injury ADHD, there was little change in the results. CONCLUSIONS: Younger age at injury places children at greater risk of impairment on measures of EF. Performance on measures of EF depends on brain variables other than frontal lobes including extrafrontal cortical brain areas and total number of lesions. The relationship between extrafrontal brain regions and EF suggests that domain-specific cognitive content (i.e. language or visuospatial analysis), mediated by the parietal or temporal lobes, may disrupt underlying cognitive processes necessary for successful performance on measures of EF. In addition, the association between total number of lesions and EF may be related to disconnections and disruption of frontal/subcortical systems.

Adolescent↗

PubMedDate not supplied

The ultrastructural basis of renal pathology in monoclonal gammopathies.

The kidney is frequently involved in the course of monoclonal gammopathies (MG). Renal involvement presents different clinical-morphological patterns, which can occur either at the onset or in a late phase of the hematological disease, as well as after chemotherapy. The reasons for the organ tropism of monoclonal immunoglobulins (Igs) are still unknown. Currently, it is well known that some primary structure alterations in monoclonal Igs and/or in their segments correlate to nephrotoxicity. On the other hand, it is impossible to predict the pathogenicity and the clinical manifestations induced by a specific monoclonal Ig based on its specific conformational modifications. Pathogenicity and organ tropism are probably complex phenomena, which involve specific protein factors, patient factors, target organ characteristics and monoclonal plasmacellular mass entities. However, aminoacidic sequence analysis of nephrotoxic Igs and some recent in vitro studies have allowed two different monoclonal light chain (LC) types to be distinguished. Glomerulopathic LCs (G-LCs) in the mesangium recognize their target structure and induce two distinct mesangiopathies, monoclonal Ig deposition disease (MIDD) and AL-amyloidosis (AL). Tubulopathic LCs (T-LCs) act on the proximal or on the distal tubule and cause, respectively, Fanconi syndrome (FS) and cast nephropathy. Pathogenic monoclonal Igs have the propensity to deposit in different renal parenchymal structures in extracellular sites, because of the transformation of soluble precursors in insoluble products. Evidence suggests that somatic mutations can destabilize the normal LCs globular soluble structure and this could be the major driving force for precipitation. Based on these features, MG can be classified as conformational and depositional diseases. Electronmicroscopy (EM) analysis of renal biopsies in MG patients with glomerular diseases distinguishes two morphological aspects. MIDD and a recently identified entity named proliferative glomerulonephritis (GN) with monoclonal IgG deposits are both characterized by non-organized granular electrondense deposits. AL, immunotactoid (IT) glomerulopathy and monoclonal cryoglobulinemia are, instead, characterized by organized deposits such as fibrils or microtubules. Tubular diseases in MG patients produce two different histological patterns. In FS, monoclonal Igs form crystals in the renal interstitium able to induce a local intense flogosis, while in cast nephropathy monoclonal Igs precipitate with Tamm-Horsfall protein (THP) in the proximal tubular lumen and induce tubular obstruction. The different morphological aspects are unrelated to specific clinical manifestations, while renal biopsy can diagnose different entities that can respond to different therapeutical schedules. This reveals the importance of the renal biopsy in the clinical management of the renal pathology in plasma cells dyscrasias, mainly when supported by the most advanced techniques of immunoelectronmicroscopy and polymerase chain reaction (PCR)-mediated analysis. Further elucidation of the molecular events involved in the pathogenesis of the different forms of renal damage is needed to design new and more effective therapeutical strategies. In particular, urinary proteomics seem to be promising in this setting.

Animals↗

PubMed1998

Comparison of different labelling index formulae used on bromodeoxyuridine-flow cytometry data.

The essence of the bromodeoxyuridine (BrdUrd)-flow cytometry (FCM) technique is that cells are labelled with the thymidine analogue BrdUrd. They are then allowed to progress through the cell cycle in a BrdUrd-free environment during the postlabelling time period. At a postlabelling time shorter than the length of the S phase (Ts), cells are fixed and prepared for FCM-mediated analysis of BrdUrd and DNA contents. From FCM-derived data, cell cycle kinetic parameters such as labelling index (LI), Ts, and potential doubling time (Tpot) can be calculated. Tpot is believed to be important in the evaluation of tumor aggressiveness and therapy response. Since LI is most commonly used together with Ts to calculate Tpot, it is important that both LI and Ts are independent of the time when cells are sampled. Several formulae to calculate LI and Ts have been presented. In the present paper, we deal with various formulae to calculate LI. These formulae differ in how they take into account unlabelled and BrdUrd-labelled cells in various fractions of the cell cycle. We present a new formula, which takes into consideration cells in the different fractions and thus makes LI theoretically independent of postlabelling time. Our results show that different LI values are obtained when different formulae are used to calculate LI. In addition, we show that the BrdUrd labelling period should be kept as short as possible.

Animals↗