UNASSIGNED: The Radiotherapy IBandronate (RIB) trial compared single dose radiotherapy and a single infusion of ibandronate in 470 bisphosphonate naïve patients with metastatic bone pain from prostate cancer randomised into a non-inferiority two arm study. Results for the primary endpoint of pain score response at 4 weeks showed that the ibandronate arm was non-inferior to single dose radiotherapy.
UNASSIGNED: In addition to pain assessments including analgesic use made at baseline, 4, 8, 12, 26 and 52 weeks, urine was collected at baseline, 4 and 12 weeks. It was subsequently analysed for urinary N-telopeptide (NTx) and cystatin C. Linear regression models were used to compare the continuous outcome measures for urinary markers within treatment arms and baseline measurements were included as covariates. Interaction terms were fitted to allow for cross-treatment group comparisons.
UNASSIGNED: The primary endpoint of the RIB trial was worst pain response at 4 weeks and there was no treatment difference seen. Urine samples and paired pain scores at 4 weeks were available for 273 patients (radiotherapy 168; ibandronate 159)The baseline samples measured for the RIB trial had an average concentration of 193 nM BCE/mM creatinine (range of 7.3-1871) compared to the quoted normal range of 33 nM BCE/mM creatinine (3 to 63). In contrast the average value of Cystatin C was 66 ng/ml (ranges ND - 1120 ng/ml) compared to the quoted normal range of 62.9 ng/ml (ranges 12.6-188 ng/ml). A statistically significant reduction in NTx concentrations between baseline and 4 weeks was seen in the ibandronate arm but not in the radiotherapy arm. No correlation between pain response and urinary marker concentration was seen in either the ibandronate or radiotherapy cohort at any time point.
UNASSIGNED: NTx was significantly raised compared to the normal range consistent with a role as a biomarker for bone metastases from prostate cancer. A significant reduction in NTx 4 weeks after ibandronate is consistent with its action in osteoclast inhibition which was not seen after radiotherapy implying a different mode of action for radiation. There was no correlation between bone biomarker levels and pain response.

BACKGROUND: Parkinson\'s disease (PD) is a neurodegenerative influenced by various clinical factors. The potential relationship between renal function and the risk of PD remains poorly understood. This study aims to explore the association between kidney function and the risk of developing PD.
METHODS: A population-based cohort study was conducted using data from 400,571 UK Biobank participants. Renal function was assessed using the estimated glomerular filtration rate (eGFR), calculated from serum creatinine and cystatin C levels. The association between eGFR levels and PD risk was evaluated using univariate and multivariate Cox regression analyses, Restricted Cubic Spline (RCS) analysis, and Kaplan-Meier analysis. Additionally, a clinical prediction model was developed and its diagnostic accuracy was evaluated using ROC analysis. A heatmap was also constructed to examine the relationship between clinical factors and gray matter volume in various brain regions.
RESULTS: Over a median observation period of 13.8 years, 2740 PD events were recorded. Cox regression and Kaplan-Meier analyses revealed a significant association between decreased eGFR and increased PD risk, particularly in participants with eGFR < 30 ml/min/1.73 m2. This association was confirmed across three adjusted models. RCS analysis demonstrated a nonlinear relationship between decreasing eGFR and increasing PD risk. Furthermore, changes in eGFR were correlated with alterations in subcortical gray matter volume in regions such as the frontal cortex, striatum, and cerebellum. The clinical prediction model showed high diagnostic accuracy with AUC values of 0.776, 0.780, and 0.824 for 4-, 8-, and 16-year predictions, respectively.
CONCLUSIONS: Renal insufficiency is significantly associated with an increased risk of PD, highlighting the importance of maintaining good kidney function as a potential preventive measure against PD.

UNASSIGNED: To evaluate the prognostic value of blood urea nitrogen/creatinine ratio (BUN/SCr) and cystatin C (Cys C) in patients with renal cell carcinoma (RCC) after radical nephrectomy.
UNASSIGNED: The study analysed 348 patients with RCC who underwent radical nephrectomy. The optimal cut-off was obtained based on the ROC of specific survival outcomes and the maximum Youden index. The patients were divided into four groups: Group 1 (low BUN/SCr-low Cys C), Group 2 (low BUN/SCr-high Cys C), Group 3 (high BUN/SCr-low Cys C), and Group 4 (high BUN/SCr-high Cys C). The primary endpoint was cancer-specific survival (CSS), and the secondary endpoint was disease-free survival (DFS).
UNASSIGNED: Cilj ovog istraživanja je bio da se proceni prognostička vrednost odnosa između azota uree i kreatinina (BUN/SCr) u krvi i cistatina C (Cys C) kod pacijenata sa karcinomom bubrega (RCC) nakon radikalne nefrektomije.
UNASSIGNED: U istraživanju je analizirano 348 pacijenata sa RCC koji su podvrgnuti radikalnoj nefrektomiji. Optimalni prag je određen na osnovu ROC krive za specifične ishode preživljavanja i maksimalnog Youden indeksa. Pacijenti su podeljeni u četiri grupe: Grupa 1 (nizak BUN/SCr - nizak Cys C), Grupa 2 (nizak BUN/SCr - visok Cys C), Grupa 3 (visok BUN/SCr - nizak Cys C) i Grupa 4 (visok BUN/SCr - visok Cys C). Primarni krajnji ishod je bio preživljavanje specifično za karcinom (CSS), a sekundarni krajnji ishod bio je preživljavanje bez bolesti (DFS).
UNASSIGNED: Pokazana je snažna pozitivna korelacija između vrednosti BUN/SCr i nivoa Cys C. Pacijenti sa višim odnosom BUN/SCr (17,41) i nivoom Cys C (3,98 mg/L) su imali lošije ishode preživljavanja. Primetno je da su pacijenti u grupi 4 pokazali najlošije stope CSS i DFS, dok pacijenti u grupama 1 i 2 imaju bolje ishode preživljavanja bez značajne razlike između ove dve grupe. Viši odnos BUN/SCr (17,41) i visok nivo seruma Cys C (3,98 mg/L) su bili nezavisni prediktori za CSS i DFS, pored veličine tumora pre operacije i patološkog T (pT) stadijuma.
UNASSIGNED: Ovo istraživanje pruža prve dokaze o nezavisnom prognostičkom značaju odnosa BUN/SCr i Cys C kod pacijenata sa RCC nakon radikalne nefrektomije.

UNASSIGNED: Reduced kidney function is a risk factor of cardiovascular and all-cause mortality. This association was demonstrated for several kidney function markers, but it is unclear whether integrating multiple measured markers may improve mortality risk prediction.
UNASSIGNED: We conducted an exploratory factor analysis (EFA) of serum creatinine- and cystatin C-based estimated glomerular filtration rate [eGFRcre and eGFRcys; derived by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and European Kidney Function Consortium (EKFC) equations], blood urea nitrogen (BUN), uric acid and serum albumin among 366 758 participants in the UK Biobank without a history of kidney failure. Fitting Cox proportional hazards models, we compared the ability of the identified latent factors to predict overall mortality and mortality by cardiovascular disease (CVD), also considering CVD-specific causes like coronary heart disease (CHD) and cerebrovascular disease.
UNASSIGNED: During 12.5 years of follow-up, 26 327 participants died from any cause, 5376 died from CVD, 2908 died from CHD and 1116 died from cerebrovascular disease. We identified two latent factors, EFA1 and EFA2, both representing kidney function variations. When using the CKD-EPI equation, EFA1 performed like eGFRcys, with EFA1 showing slightly larger hazard ratios for overall and CVD-related mortality. At 10 years of follow-up, EFA1 and eGFRcys showed moderate discrimination performance for CVD-related mortality, outperforming all other kidney indices. eGFRcre was the least predictive marker across all outcomes. When using the EKFC equation, eGFRcys performed better than EFA1 while all other results remaining similar.
UNASSIGNED: While EFA is an attractive approach to capture the complex effects of kidney function, eGFRcys remains the most practical and effective measurement for all-cause and CVD mortality risk prediction.

OBJECTIVE: To explore the causal relationship between cystatin C levels and different stages of diabetic retinopathy through Mendelian randomization (MR).
METHODS: The MRC Integrative Epidemiology Unit provided the Genome-wide association studies (GWAS) data related to cystatin C (exposure). GWAS data for outcomes [DR, proliferative diabetic retinopathy (PDR), severe non-proliferative background diabetic retinopathy (SNPBDR)] were sourced from the FinnGen. Adopted Inverse Variance Weighting (IVW), MR-Egger regression MR-PRESSO, Weighted Median, Constrained Maximum Likelihood and Model Averaging (cML-MA), Weighted model, Radial MR, and MR-Lasso to estimate the causal relationship between cystatin C and diabetic retinopathy. We conducted multivariable MR analysis to evaluate the independent causal effects of cystatin C levels on diabetic retinopathy.
RESULTS: Based on the IVW method, we observed a causal relationship between cystatin C and diabetic retinopathy [odds ratio (OR)random effect = 1.137, 95% confidence interval (CI): 1.035-1.250]/PDR (ORrandom effect = 1.123, 95%CI: 1.004-1.255)/SNPBDR (ORfixed effect = 2.002, 95%CI: 1.343-2.986). Consistent findings were obtained through the cML-MA method. Cochran\'s Q test suggested the presence of heterogeneity between the cystatin C level and instrumental variables in relation to diabetic retinopathy and proliferative diabetic retinopathy, respectively. After adjusting for outliers using MR-PRESSO and Radial MR, it was observed that the statistical significance of the association between cystatin C level and diabetic retinopathy persists. Reverse MR analysis indicated that genetically related SNPBDR may influence the cystatin C level. In multivariable MR analysis, there were indications suggesting a causal relationship of cystatin C with the risk of DR/PDR/SNPBDR adjusting for confounders.
CONCLUSIONS: This study utilizes Mendelian randomization analyses to establish a causal relationship between cystatin C and diabetic retinopathy, and reveals the impact of cystatin C on the risk of diabetic retinopathy, thus providing new evidence for clinical intervention of diabetic retinopathy.

UNASSIGNED: Extensive researches highlight the detrimental impact of sleep disorders such as insomnia and insufficient sleep duration on kidney function. However, establishing a clear causal relationship between insomnia, sleep duration, and kidney function remains challenging. This study aims to estimate this relationship using Mendelian randomization (MR).
UNASSIGNED: Independent genetic variants strongly associated with insomnia (N = 462,341) and sleep duration (N = 460,099) were selected as instrumental variables from corresponding genome-wide association studies (GWAS). Kidney function parameters, including serum creatinine, estimated glomerular filtration rate by cystatin C (eGFRcys), acute renal failure (ARF), chronic renal failure (CRF), kidney injury molecule-1, neutrophil gelatinase associated lipocalin, microalbuminuria, cystatin C, and β2 microglobulin, were derived from GWAS databases. A two-sample MR study was conducted to assess the causal relationship between sleep disorders and kidney function, and multivariable MR was used to identify potential mediators. The inverse-variance weighted was used as the primary estimate.
UNASSIGNED: MR analysis found robust evidence indicating that insomnia and short sleep duration were associated with an increased risk of elevated serum creatinine, regardless of adjusting for obesity. Causal links between sleep duration and eGFRcys or cystatin C were also identified. While genetically predicted insomnia and sleep duration were found to potentially impact ARF, CRF, microalbuminuria, and β2 microglobulin, the p-values in multivariable MR analysis became nonsignificant. No pleiotropy was detected.
UNASSIGNED: This study demonstrates a causal impact of insomnia on the risk of elevated serum creatinine and a positive effect of sleep duration on serum creatinine, eGFRcys, and cystatin C. Our findings also suggest their potential indirect effects on ARF, CRF, microalbuminuria, and β2 microglobulin mediated by obesity.

The present study aimed to explore the association between serum cystatin C (Cys-C) levels and visceral fat area (VFA) in patients with type 2 diabetes mellitus (T2DM). A total of 208 previously diagnosed T2DM patients who visited our hospital from September 2019 to December 2021 were included and divided into three groups based on tertiles of Cys-C levels, namely, Groups C1, C2, and C3. The clinical data of the subjects were collected, biochemical parameters such as Cys-C levels were determined, and bioelectrical impedance analysis was applied to determine the VFA and subcutaneous fat area (SFA). The VFA in Group C1 was lower than that in Groups C2 and C3 (all P < 0.05), with no significant difference in VFA between Groups C2 and C3 (P > 0.05). Spearman\'s correlation analysis revealed that the serum Cys-C level was positively correlated with age, VFA, SFA, insulin resistance index, waist circumference, body mass index, systolic blood pressure, serum creatinine level, and blood uric acid level (r = 0.543, 0.353, 0.168, 0.148, 0.365, 0.264, 0.25, 0.497, and 0.155, respectively; P < 0.05) and negatively correlated with glycated haemoglobin levels (r = -0.175, P < 0.05). Univariate linear regression analysis revealed that VFA was positively correlated with the Cys-C level (β = 0.002, 95% CI = 0.001-0.003, P < 0.05), with an increase of 0.002 mg/L in the Cys-C level for each 1 cm2 increase in VFA. Further multivariate linear regression analysis was performed with the serum Cys-C level as the dependent variable and age, VFA, SFA, insulin resistance (HOMA-IR), WC, BMI, SBP, Cr, UA, and HbA1c as the independent variables. The results suggested that VFA was positively correlated with serum Cys-C level (β = 0.001, 95% CI = 0.000-0.002, P < 0.05), with serum Cys-C levels increasing by 0.001 mg/L for every 1 cm2 increase in VFA. Using a VFA ≥ 100 cm2 as the criterion for visceral obesity, ROC analysis revealed that the Cys-C level was a better predictor of visceral obesity, with an area under the ROC curve (AUC) of 0.701 (95% CI = 0.631-0.771, P < 0.05), an optimal cut-off of 0.905 mg/L, and a sensitivity and specificity of 58.3% and 75.2%, respectively. The results suggested that the serum Cys-C level was correlated with the VFA in patients with T2DM and that Cys-C may play a vital role in T2DM patients with visceral obesity.

Chronic kidney disease (CKD) is a microvascular complication that frequently affects numerous patients diagnosed with diabetes. For the diagnosis of CKD, the guidelines recommend the identification of the urinary albumin/creatinine ratio and the determination of serum creatinine, based on which the estimated rate of glomerular filtration (eGFR) is calculated. Serum creatinine is routinely measured in clinical practice and reported as creatinine-based estimated glomerular filtration rate (eGFRcr). It has enormous importance in numerous clinical decisions, including the detection and management of CKD, the interpretation of symptoms potentially related to this pathology and the determination of drug dosage. The equations based on cystatin C involve smaller differences between race groups compared to GFR estimates based solely on creatinine. The cystatin C-based estimated glomerular filtration rate (eGFRcys) or its combination with creatinine (eGFRcr-cys) are suggested as confirmatory tests in cases where creatinine is known to be less precise or where a more valid GFR estimate is necessary for medical decisions. Serum creatinine is influenced by numerous factors: age, gender, race, muscle mass, high-protein diet, including protein supplements, and the use of medications that decrease tubular creatinine excretion (H2 blockers, trimethoprim, fenofibrate, ritonavir, and other HIV drugs). The low levels of creatinine stemming from a vegetarian diet, limb amputation, and conditions associated with sarcopenia such as cirrhosis, malnutrition, and malignancies may lead to inaccurately lower eGFRcr values. Therefore, determining the GFR based on serum creatinine is not very precise. This review aims to identify a new perspective in monitoring renal function, considering the disadvantages of determining the GFR based exclusively on serum creatinine.

A phospholipid bilayer is a typical structure that serves crucial functions in various cells and organelles. However, it is not unusual for it to take part in pathological processes. The cell membrane may be a binding target for amyloid-forming proteins, becoming a factor modulating the oligomerization process leading to amyloid deposition-a hallmark of amyloidogenic diseases-e.g., Alzheimer\'s disease. The information on the mechanisms governing the oligomerization influenced by the protein-membrane interactions is scarce. Therefore, our study aims to describe the interactions between DPPA, a cell membrane mimetic, and amyloidogenic protein human cystatin C. Circular dichroism spectroscopy and differential scanning calorimetry were used to monitor (i) the secondary structure of the human cystatin C and (ii) the phase transition temperature of the DPPA, during the protein-membrane interactions. NMR techniques were used to determine the protein fragments responsible for the interactions, and molecular dynamics simulations were applied to provide a molecular structure representing the interaction. The obtained data indicate that the protein interacts with DPPA, submerging itself into the bilayer via the AS region. Additionally, the interaction increases the content of α-helix within the protein\'s secondary structure and stabilizes the whole molecule against denaturation.

Vancomycin, a first-line drug for treating methicillin-resistant Staphylococcus aureus infections, is associated with acute kidney injury (AKI). This study involved an evaluation of biomarkers for AKI detection and their comparison with traditional serum creatinine (SCr). We prospectively enrolled patients scheduled to receive intravenous vancomycin for methicillin-resistant S aureus infection. Blood samples for pharmacokinetic assessment and SCr and cystatin C (CysC) measurements were collected at baseline and on days 3, 7, and 10 from the initiation of vancomycin administration (day 1). Urinary biomarkers, including kidney injury molecule 1 (KIM-1), neutrophil gelatinase-associated lipocalin, and clusterin, were collected from days 1 to 7 and adjusted for urinary creatinine levels. The estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. Of the 42 patients, 6 experienced vancomycin-induced AKI. On day 7, the change from baseline eGFR using CysC (ΔeGFRCysC) showed a stronger correlation with vancomycin area under the curve (r = -0.634, P < .001) than that using SCr (ΔeGFRSCr; r = -0.437, P = .020). ΔeGFRSCr showed no significant correlation with vancomycin pharmacokinetic in patients with body mass index ≥23. The median (interquartile range) level of KIM-1 (μg/mg) was significantly higher in the AKI group (0.006 [0.005-0.008]) than in the non-AKI group (0.004 [0.001-0.005]) (P = .039, Mann-Whitney U test), with area under the receiver operating characteristic curve (95% confidence interval) of 0.788 (0.587-0.990). Serum CysC, particularly in overweight individuals or those with obesity, along with urinary KIM-1 are important predictors of vancomycin-induced AKI. These results may aid in selecting better biomarkers than traditional SCr for detecting vancomycin-induced AKI.