Development and Validation of a Nomogram Model to Predict Acute Kidney Disease After Nephrectomy in Patients with Renal Cell Carcinoma

Purpose

To develop and validate a nomogram model to predict the occurrence of acute kidney disease (AKD) after nephrectomy.

Patients and Methods

A retrospective cohort including 378 patients with renal cell carcinoma (RCC) who had undergone radical or partial nephrectomy between March 2013 and December 2017 at the First Affiliated Hospital of Zhengzhou University was analyzed. Of these, patients who had undergone surgery in an earlier period of time formed the training cohort (n=265) for nomogram development, and those who had undergone surgery thereafter formed the validation cohort (n=113) to confirm the model's performance. The incidence rate of AKD was measured. Univariate and multivariate logistics regression analysis was used to estimate the independent risk factors associated with AKD. The independent risk factors were incorporated into the nomogram. The accuracy and utility of the nomogram were evaluated by calibration curve and decision curve analysis, respectively.

Results

Overall, AKD occurred in 27.5% and 28.3% of patients in the training and validation cohorts, separately. The final nomogram included surgery approach, Charlson comorbidity index (CCI), and the decrement of eGFR. This model achieved good concordance indexes of 0.78 (95% CI=0.71-0.84) and 0.76 (95% CI=0.67-0.86) in the training and validation cohorts, respectively. The calibration curves and decision curve analysis (DCA) demonstrated the accuracy and the clinical usefulness of the proposed nomogram, separately.

Conclusion

The nomogram accurately predicts AKD after nephrectomy in patients with RCC. The risk for patients' progress into AKD can be determined, which is useful in guiding clinical decisions.

Prevalence and risk factors of chronic kidney disease and diabetic kidney disease in a central Chinese urban population: a cross-sectional survey

Background

This study was conducted to evaluate and update the current prevalence of and risk factors for chronic kidney disease (CKD) and diabetic kidney disease (DKD) in a central Chinese urban population.

Methods

From December 2017 to June 2018, a total of 5231 subjects were randomly enrolled from 3 communities in 3 districts of Zhengzhou. CKD was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min.1.73m² or urinary albumin to creatinine ratio ≥ 30 mg/g (albuminuria). Diabetic subjects with systolic blood pressure > 140 mmHg, albuminuria or an eGFR less than 60 mL/min/1.73 m² were classified as having DKD. Participants completed a questionnaire assessing lifestyle and relevant medical history, and blood and urine specimens were taken. Serum creatinine, uric acid, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein and urinary albumin were assessed. The age- and sex-adjusted prevalences of CKD and DKD were calculated, and risk factors associated with the presence of reduced eGFR, albuminuria, DKD, severity of albuminuria and progression of reduced renal function were analyzed by binary and ordinal logistic regression.

Results

The overall adjusted prevalence of CKD was 16.8% (15.8–17.8%) and that of DKD was 3.5% (3.0–4.0%). Decreased renal function was detected in 132 participants (2.9, 95% confidence interval [CI]: 2.5–3.2%), whereas albuminuria was found in 858 participants (14.9, 95% CI: 13.9–15.9%). In all participants with diabetes, the prevalence of reduced eGFR was 6.3% (95% CI = 3.9–8.6%) and that of albuminuria was 45.3% (95% CI = 40.4–50.1%). The overall prevalence of CKD in participants with diabetes was 48.0% (95% CI = 43.1–52.9%). The results of the binary and ordinal logistic regression indicated that the factors independently associated with a higher risk of reduced eGFR and albuminuria were older age, sex, smoking, alcohol consumption, overweight, obesity, diabetes, hypertension, dyslipidemia and hyperuricemia.

Conclusions

Our study shows the current prevalence of CKD and DKD in residents of Central China. The high prevalence suggests an urgent need to implement interventions to relieve the high burden of CKD and DKD in China.

Helicobacter pylori Infection is Associated with Occurrence of Proteinuria in Type 2 Diabetes Patients: A Systemic Review and Meta-Analysis

BACKGROUND

Type 2 diabetes (T2DM) patients are susceptible to Helicobacter pylori (HP), and it has been reported that the occurrence of proteinuria is associated with HP infection in T2DM patients; however, this view remains controversial. This meta-analysis aimed to explore the association between HP infection and the occurrence of proteinuria in T2DM patients. In addition, we hope to provide some recommendations to readers in clinical or related fields.

METHODS

Our meta-analysis was conducted with the methodology of the Cochrane Collaboration. Search strategies were formulated by relevant professionals. Case-control studies that compared the occurrence of proteinuria in T2DM patients with and without HP infection were involved in our meta-analysis. Relevant English or Chinese studies were searched on online databases before 2018, including PubMed, the Cochrane library, Medline, Google Scholar, the China National Infrastructure, and Wanfang database. The search strategies were "diabetic proteinuria, diabetic microalbuminuria, diabetic albuminuria, diabetic kidney disease, diabetic renal dysfunction, diabetic renal disease, diabetic nephropathy, diabetic complications, and diabetic mellitus, combined with HP." The quality of these involved articles was separately assessed by two investigators using the Newcastle-Ottawa Scale (NOS). Odds ratios (ORs) and associated 95% confidence intervals (CIs) were extracted and pooled using fixed-effects models.

RESULTS

Seven studies involving 1029 participants were included. The quality of these seven articles was all above five stars as assessed by NOS, and there was no significant publication bias in our meta-analysis. We found that T2DM patients with HP infection had a 2.00 times higher risk of the occurrence of proteinuria than patients without HP infection (OR: 2.00, 95% CI: 1.48-2.69).

CONCLUSIONS

Our analysis showed that HP infection was associated with the occurrence of proteinuria in T2DM patients. HP radical surgery might be a therapeutic option for protecting kidney function in patients with T2DM.

PDK2 promotes chondrogenic differentiation of mesenchymal stem cells by upregulation of Sox6 and activation of JNK/MAPK/ERK pathway

This study was undertaken to clarify the role and mechanism of pyruvate dehydrogenase kinase isoform 2 (PDK2) in chondrogenic differentiation of mesenchymal stem cells (MSCs). MSCs were isolated from femurs and tibias of Sprague-Dawley rats, weighing 300-400 g (5 females and 5 males). Overexpression and knockdown of PDK2 were transfected into MSCs and then cell viability, adhesion and migration were assessed. Additionally, the roles of aberrant PDK2 in chondrogenesis markers SRY-related high mobility group-box 6 (Sox6), type ΙΙ procollagen gene (COL2A1), cartilage oligomeric matrix protein (COMP), aggrecan (AGC1), type ΙX procollagen gene (COL9A2) and collagen type 1 alpha 1 (COL1A1) were measured by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The expressions of c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK) and extracellular regulated protein kinase (ERK) were measured. Overexpressing PDK2 promoted cell viability, adhesion and inhibited cell migration in MSCs (all P<0.05). qRT-PCR assay showed a potent increase in the mRNA expressions of all chondrogenesis markers in response to overexpressing PDK2 (P<0.01 or P<0.05). PDK2 overexpression also induced a significant accumulation in mRNA and protein expressions of JNK, p38MAPK and ERK in MSCs compared to the control (P<0.01 or P<0.05). Meanwhile, silencing PDK2 exerted the opposite effects on MSCs. This study shows a preliminary positive role and potential mechanisms of PDK2 in chondrogenic differentiation of MSCs. It lays the theoretical groundwork for uncovering the functions of PDK2 and provides a promising basis for repairing cartilage lesions in osteoarthritis.

GSK-3β inhibitor attenuates urinary albumin excretion in type 2 diabetic db/db mice, and delays epithelial-to-mesenchymal transition in mouse kidneys and podocytes

The mechanism underlying epithelial‑to‑mesenchymal transition (EMT) caused by high glucose (HG) stimulation in diabetic nephropathy (DN) remains to be fully elucidated. The present study investigated the effects of HG on EMT and the activity of glycogen synthase kinase 3β (GSK‑3β) in podocytes and the kidneys of db/db mice, and assessed the effects of (2'Z, 3'E)‑6‑bromoindirubin‑3'‑oxime (BIO), an inhibitor of GSK‑3β, on EMT and glomerular injury. The resulting data showed that the activity of GSK‑3β was upregulated by HG and downregulated by BIO in the podocytes and the renal cortex. The expression levels of epithelial markers, including nephrin, podocin and synaptopodin, were decreased by HG and increased by BIO, whereas the reverse were true for mesenchymal markers, including α‑smooth muscle actin (α‑SMA) and fibronectin. The expression levels of β‑catenin and Snail, in contrast to current understanding of the Wnt signaling pathway, were increased by HG and decreased by BIO. In addition, expression of the vitamin D receptor (VDR) was decreased by HG and increased by BIO. In conclusion, the present study revealed that the mechanism by which BIO inhibited HG‑mediated EMT in podocytes and the renal cortex was primarily due to the VDR. Treatment with BIO protected renal function by maintaining the integrity of the filtration membrane and decreasing UAE, but not by regulating blood glucose. Therefore, GSK‑3β may be used as a sensitive biomarker of DN, and its inhibition by BIO may be effective in the treatment of DN.

Effect of GBOT on blood lipid and blood glucose metabolism in rats with atherosclerosis

We observed the variation in in vivo blood lipid and blood glucose metabolism in rats with atherosclerosis after 5-(3,4-dihydroxy-phenyl)-1-piperidin-1-yl-penta-2,4-dien-1-one (GBOT) administration. Wistar rats aged 10 weeks received a high-fat diet to establish the atherosclerosis model. Metabolic indices related to blood lipid and blood glucose were measured before modeling and at 4 and 8 weeks after modeling. Liver fat levels in rats were measured at 8 weeks to analyze the relationship between liver fat and blood lipid levels. We examined the mechanism of blood lipid reduction. The levels of serum triglycerides, total cholesterol, and very-low-density lipoprotein cholesterol in rats in the control group were significantly decreased (P < 0.05) compared with those in the 4-week control group at 4 weeks and decreased significantly and continuously until the 8th week (P < 0.05). Compared with the 8-week control group, the blood glucose level in rats in the 8-week experimental group decreased significantly (P < 0.05), and the level of insulin sensitivity index decreased significantly (P < 0.05). Compared with the control group, triglyceride and total cholesterol levels per unit mass in rat liver tissue in the 8-week experimental group decreased significantly (P < 0.05). Western blotting indicated that GBOT significantly increased the expression of lecithin-cholesterol acyltransferase, low-density lipoprotein receptor, and cholesterol 7 alpha-hydroxylase proteins. GBOT can significantly decrease the levels of blood lipid and blood glucose in rat models of atherosclerosis, and its mechanism may be associated with the promotion of expression of lecithin-cholesterol acyltransferase, low-density lipoprotein receptor, and cholesterol 7 alpha-hydroxylase proteins.

QAM accommodated double-side band fast OFDM based on IDCT

In this paper, we theoretically and experimentally prove that sub-carriers in double-side band fast orthogonal frequency division multiplexing (DSB-FOFDM) are orthogonal over a symbol interval independent of the signal phase and amplitude. Therefore, the commonly utilized DSB-FOFDM is quadrature amplitude modulation (QAM) accommodated; while previously DSB-FOFDM was usually modulated by amplitude shift keying (ASK) or binary phase shift keying (BPSK). In our proof-of-concept experiments, bit error ratio (BER) performance of 10 Gb/s quadrature phase shift keying (QPSK) modulated DSB-FOFDM was equivalent to that of 10 Gb/s QPSK modulated OFDM after 500 km standard single mode fiber (SSMF) transmission. 10 Gb/s QPSK modulated DSB-FOFDM largely outperformed the commonly utilized 4-ASK modulated DSB-FOFDM in BER performance. Additionally, BER performance of 10 Gb/s 16-QAM modulated DSB-FOFDM was equivalent to that of 10 Gb/s 16-QAM modulated OFDM after 500 km SSMF transmission.