Population Pharmacokinetic Modeling of Diltiazem in Chinese Renal Transplant Recipients.

BACKGROUND AND OBJECTIVES: Diltiazem is a benzothiazepine calcium blocker and widely used in renal transplant patients since it improves the level of tacrolimus or cyclosporine A concentration. Several population pharmacokinetic (PopPK) models had been established for cyclosporine A and tacrolimus but no specific PopPK model was established for diltiazem. The aim of the study is to develop a PopPK model for diltiazem in renal transplant recipients and provide relevant pharmacokinetic parameters of diltiazem for further pharmacokinetic interaction study. METHODS: Patients received tacrolimus as primary immunosuppressant agent after renal transplant and started administration of diltiazem 90 mg twice daily on 5th day. The concentration of diltiazem at 0, 0.5, 1, 2, 8, and 12 h was measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Genotyping for CYP3A4*1G, CYP3A5*3, and MDR1 3435 was conducted by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). 25 covariates were considered in the stepwise covariate model (SCM) building procedure. RESULTS: One-compartment structural pharmacokinetic model with first-order absorption and elimination was used to describe the pharmacokinetic characteristics of diltiazem. Total bilirubin (TBIL) influenced apparent volume of distribution (V/F) of diltiazem in the forward selection. The absorption rate constant (K a), V/F, and apparent oral clearance (CL/F) of the final population pharmacokinetic (PopPK) model of diltiazem were 1.96/h, 3550 L, and 92.4 L/h, respectively. CONCLUSION: A PopPK model of diltiazem is established in Chinese renal transplant recipients and it will provide relevant pharmacokinetic parameters of diltiazem for further pharmacokinetic interaction study.

Induction of apoptosis and autophagy by calcifying nanoparticles in human bladder cancer cells.

Calcifying nanoparticles have been linked to various types of human disease, but how they contribute to disease processes is unclear. Here, we examined whether and how calcifying nanoparticles isolated from patients with kidney stones are cytotoxic to human bladder cancer cells. Calcifying nanoparticles were isolated from midstream urine of patients with renal calcium oxalate stones and examined by electron microscopy. Human bladder cancer cells (EJ cells) were cultured in the presence of calcifying nanoparticles or nanohydroxyapatites for 12 and 72 h and examined for toxicity using the Cell Counting Kit-8, for autophagy using transmission electron microscopy and confocal microscopy, and for apoptosis using fluorescence microscopy, transmission electron microscopy, and flow cytometry. Changes in protein expression were analyzed by Western blotting. The results showed that the size and shape of the isolated calcifying nanoparticles were as expected. Calcifying nanoparticles were cytotoxic to EJ cells, more so than nanohydroxyapatites, and this was due, at least in part, to the production of intracellular reactive oxygen species. Transmission electron microscopy showed that calcifying nanoparticles were packaged into vesicles and autolysosomes. Calcifying nanoparticles induced greater autophagy and apoptosis than nanohydroxyapatites. Our findings demonstrate that calcifying nanoparticles can trigger bladder cancer cell injury by boosting reactive oxygen species production and stimulating autophagy and apoptosis.

All-fiber passively Q-switched 604 nm praseodymium laser with a Bi2Se3 saturable absorber.

We experimentally demonstrated a simple passively Q-switched praseodymium (Pr3+)-doped all-fiber laser at 604 nm with a Bi2Se3 saturable absorber (SA). A Bi2Se3/polyvinyl alcohol composite film is sandwiched between two ferrules to construct a fiber-compatible Q-switcher. Two fiber end facet mirrors build a compact-linear resonator. The repetition rate of the achieved 604 nm Q-switching pulse can be widely tuned from 86.2 to 187.4 kHz, and the pulse duration can be as narrow as 494 ns. To the best of our knowledge, this is the shortest operation wavelength of a Bi2Se3-based pulsed all-fiber laser at 604 nm.

Preprocedural Prediction Model for Contrast-Induced Nephropathy Patients.

BACKGROUND: Several models have been developed for prediction of contrast-induced nephropathy (CIN); however, they only contain patients receiving intra-arterial contrast media for coronary angiographic procedures, which represent a small proportion of all contrast procedures. In addition, most of them evaluate radiological interventional procedure-related variables. So it is necessary for us to develop a model for prediction of CIN before radiological procedures among patients administered contrast media. METHODS AND RESULTS: A total of 8800 patients undergoing contrast administration were randomly assigned in a 4:1 ratio to development and validation data sets. CIN was defined as an increase of 25% and/or 0.5 mg/dL in serum creatinine within 72 hours above the baseline value. Preprocedural clinical variables were used to develop the prediction model from the training data set by the machine learning method of random forest, and 5-fold cross-validation was used to evaluate the prediction accuracies of the model. Finally we tested this model in the validation data set. The incidence of CIN was 13.38%. We built a prediction model with 13 preprocedural variables selected from 83 variables. The model obtained an area under the receiver-operating characteristic (ROC) curve (AUC) of 0.907 and gave prediction accuracy of 80.8%, sensitivity of 82.7%, specificity of 78.8%, and Matthews correlation coefficient of 61.5%. For the first time, 3 new factors are included in the model: the decreased sodium concentration, the INR value, and the preprocedural glucose level. CONCLUSIONS: The newly established model shows excellent predictive ability of CIN development and thereby provides preventative measures for CIN.

Contrast Media-Induced Renal Inflammation Is Mediated Through HMGB1 and Its Receptors in Human Tubular Cells.

With the rapid development of imaging diagnosis and interventional therapy, contrast media (CM) are widely used in clinics. However, contrast-induced nephropathy (CIN) is the third leading cause of hospital-acquired acute renal failure accounting for 10-12% of all causes of hospital-acquired renal failure. Recent study found that inflammation may participate in the pathogenesis of CIN, but the role of it remains unclear. HK-2 cells were treated with Iohexol, Urografin, and mannitol. Two types of CM increased the release of HMGB1 in cell supernatant accompanied by increased expression of TLR2 and CXCR4. Iohexol and Urografin also caused a significant increase in NF-κB followed by the release of IL-6 and MCP-1. To clarify the role of HMGB1, TLR2, and CXCR4, glycyrrhizin, anti-TLR2-IgG, and AMD3100 were used to inhibit HMGB1, TLR2, and CXCR4, respectively. Significant decrease in the expression of TLR2, CXCR4, nuclear NF-κB, and the release of IL-6 and MCP-1 were observed. These results indicate that TLR2 and CXCR4 signaling are involved in CM-induced HK-2 cell injury model in an HMGB1-dependent pathway, which may provide a new target for the prevention and the treatment of CIN.

Superb microvascular imaging in diagnosis of breast lesions: a comparative study with contrast-enhanced ultrasonographic microvascular imaging.

OBJECTIVE: To evaluate the diagnostic performance of superb microvascular imaging (SMI) in breast lesions, comparing with contrast-enhanced ultrasonographic microvascular imaging (MVI). METHODS: From April to November 2015, 132 patients (with 132 breast lesions) were enrolled in the retrospective study. All lesions were evaluated with colour Doppler flow imaging (CDFI), colour SMI (cSMI), monochrome SMI (mSMI) and contrast-enhanced ultrasonographic MVI. Receiver-operating characteristic curve analysis was performed to compare the diagnostic performance of SMI and MVI for discrimination between benign and malignant breast lesions. RESULTS: Histological analysis showed 58 malignant and 74 benign lesions. mSMI was more sensitive in detecting blood flow signals in breast lesions than CDFI (p < 0.001) and cSMI (p < 0.001). Differences of vessels inside breast lesions and morphologic features of vessels between benign and malignant lesions were statistically significant on mSMI (p < 0.001). Using root hair-like and crab claw-like patterns as the criteria for malignant lesions, the sensitivity, specificity and accuracy for differentiation based on the microvascular architecture patterns were 77.6, 90.5 and 84.8% for mSMI and 89.6, 87.8 and 88.6% for MVI. Areas under curve of mSMI and MVI were not significantly different (p = 0.129). CONCLUSION: mSMI can increase blood flow detection and depict the microvascular architecture of breast lesions. The diagnostic performance of mSMI was not significantly different from MVI. SMI has potential in the differential diagnosis of breast lesions. ADVANCES IN KNOWLEDGE: mSMI is a non-invasive technique for vascularity evaluation of breast tumours and it is beneficial for breast tumour differentiation.

[Association of serum testosterone with atherosclerosis in middle-aged and elderly men].

OBJECTIVE: To investigate the association between the level of serum testosterone and atherosclerosis in middle-aged and elderly men. METHODS: We conducted a population-based study of 413 males aged 40-75 years in a community in Guangzhou. We obtained the sociodemographic characteristics, clinical data, physical measurements, and laboratory results of sex hormones, blood glucose, and blood lipid of the subjects. We also measured the carotid intima media thickness (CIMT) by color Doppler ultrasonography. RESULTS: The subjects were divided into a carotid atherosclerosis (CAS) group (CIMT ≥ 0.9 mm) and a non-CAS group (CIMT < 0.9 mm). The medians of free testosterone (FT) were 57.41 and 59.72 pmol/L in the CAS and non-CAS groups, respectively (P = 0.005), and no significant difference was found between the two groups in total testosterone (TT). The levels of serum FT and TT were negatively correlated to CIMT, with Spearman's rank correlation coefficients of -0.126 (P = 0.011) and -0.188 (P < 0.001), respectively. The incidence rates of CAS were 23.30, 13.46, 17.48, and 7.77% in the Q1, Q2, Q3, and Q4 groups, respectively according to the quartile of FT (P for trend = 0.008) and 17.48, 18.27, 16.50, and 9.71% respectively according to the quartile of TT (P for trend = 0.116). Based on the quartile of FT and after adjustment for age, waist circumference, systolic blood pressure, and HbAlc, the risk of CAS was significantly increased in the Q1 group as compared with Q4 (OR = 2.491, 95% CI 1.01-6.149), but no statistically significant differences were observed according to the quartile of TT. CONCLUSION: A low serum FT level may be a risk factor of atherosclerosis in Chinese men aged 40 years or older.

[Changes of AFP and beta-hCG in testicular tumors analyzed by a function method].

OBJECTIVE: To establish a new function method for the analysis of a-fetoprotein (AFP) and beta-hCG in testicular tumors. METHODS: We reexamined the serum levels of AFP and beta-hCG after radical orchiectomy, and calculated the measured coordinate, with the abscissa representing the number of the half-lives of tumor markers, and the ordinate representing the measured value of tumor markers. Referring to the measured value of tumor markers before surgery as a, the number of half-lives as x, and their theoretical value over a period of x elimination half-lives as y (logarithm to the base 2 of y), we calculated the predicted coordinate according to the formula y = log2(a/2x) ==> x + y = log2a (function 1). Then we assessed tumor residue and metastasis by analyzing the relationship between the measured and predicted coordinates. RESULTS: The pathological examination of case 1 revealed a germ cell tumor of a mixed histological pattern of syncytiotrophoblast and yolk sac tumor. The measured coordinates of AFP and beta-hCG were (2.22, 6.21) and (10, 8.38), and the predicted coordinates (2.22, 6.34) and (10, 4.41) , indicating the elimination of the yolk sac tumor and metastasis of the syncytiotrophoblast tumor. Case 2 demonstrated the mixed pathological nature of teratocarcinoma and yolk sac tumor. The measured coordinates of AFP and beta-hCG were (2.67, -1.03) and (12, -3.32), and the predicted coordinates (2.67, 1.41) and (12, -5.80). But the review times of AFP and beta-hCG were out of the effective range of half-lives, with the measured values below the normal, which suggested no tumor residue or metastasis. Case 3 was found to be embryonal carcinoma. The measured coordinate of AFP was (0.22, 9.25) , and the predicted coordinate (0.22, 9.55) , indicating the elimination of tumor. CONCLUSION: The change of the tumor markers predicted by the function method coincided with the natural course of disease in the three cases. The coincidence of the measured with the predicted coordinate after radical orchiectomy indicates no metastasis, while their disagreement suggests possible residue and metastasis of the tumor.

[Expression of cellular adhesion molecules and HLA-DR antigen on vascular endothelial cells in hemangiomas.].

PURPOSE: To investigate the expression and function of the adhesion molecules ICAM-3, CD34 and HLA-DR antigen on endothelial cells of hemangiomas in different stages. METHODS: SABC immunohistochemical technique was used to examine the expression of ICAM-3, CD34 and HLA-DR on vascular endothelial cells. Seventy-six specimens including 28 proliferating hemangiomas, 22 involuting hemangiomas, 18 vascular deformity and 8 normal skin tissue were obtained from infants and children for the experiment. RESULTS: The results showed: (1) both ICAM-3 and CD34 had high expression in proliferating hemangiomas, but poor or even no expression in involuting hemangiomas. There was a significant difference (P<0.001) between the two phases. Both ICAM-3 and CD34 had almost no expression in vascular deformity and normal skin tissue, significantly different from hemangiomas (P<0.001).(2) HLA-DR expression was closely related to the high differentiation phase of vascular epithelial cells. In the proliferating phase, HLA-DR didn't express, while it expressed highly as endothelial cells were in well-matured involuting phase. These differences were significant (P<0.001). CONCLUSION: ICAM-3 and CD34 might play a role in the early stage of angiogenesis and take part in the pathological genesis and regression process of hemangiomas by regulating endothelial cells adhesion; HLA-DR might be related either to acquisition of a mature phenotype or to an activated state of the endothelial cells.

[Gene expression differences between high and low metastatic cells of adenoid cystic carcinoma].

OBJECTIVE: To investigate the complex differences between high metastatic and low metastatic cells of the Adenoid cystic Carcinoma. METHODS: Gene expression patterns were examined in high metastatic cell ACC-M strain and low metastatic ACC-2 strain with the method SSH (suppression subtractive hybridization). RESULTS: although extensive similarity was noted between the expression profiles, twelve genes were highly expressed of, in low metastatic cell ACC-2 tester, compared with driver, high metastatic cell ACC-M. These genes were cysteine-rich angiogenic-inducer protein (cyr61), chromosome7 clone RP11-52501, G protein, was family member Iferritin heavy polypeptide I, jumping translocation breakpoint, eukaryotic translation elongation, folate receptor, ribosomal proteins L7a, S21, P0 and other two novel genes-ACC metastasis-associated RNH and ACC metastasis-associated suspected protein. GenBank accession number were AF522024 and AF522025 respectively. CONCLUSIONS: the result suggests that the obtainment of the ability of metastasis is related to the low expression or mutation of these genes. These data provide insight into the extent of expression differences underlying metastasis-related genes that may prove useful as diagnostic or prognostic markers.

Protein and mRNA characterization in high and low metastasis adenoid cystic carcinoma cell lines.

Metastasis and invasion, the important characteristics of malignant tumors, are closely associated with a series of changes in the expression of genes and proteins. In this study, we compare mRNA and protein expression in high and low metastasis adenoid cystic carcinoma cell lines by mRNA suppression subtractive hybridization and two-dimensional electrophoresis combined with peptide mass fingerprint analysis. 34 differentially expressed genes were obtained using suppression subtractive hybridization experiments including 6 highly expressed gene sequences in the high metastasis cell line, and 28 in the low metastasis cell line. RNA dot blot hybridization further confirmed the results after excluding false positives. For protein analysis, ten significantly different protein spots were detected using two-dimensional gel electrophoresis technique combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI- TOF-MS). The results then compare with the SWISS PROT database. These results suggest that high tumor metastasis of adenoid cystic carcinoma is associated with multiple genes whose function include angiogenesis, protein synthesis, signal transduction, modulation of cell cycle, molecular chaperones, and immune co-stimulating molecule. Moreover, the results of the phenotypic function-related expression mapping analysis at the mRNA and protein level revealed obvious complementarities, providing important clues for further study of the molecular mechanism of metastasis, metastasis control and possible targets for cancer gene therapy.

Relationship between mammaglobin expression and estrogen receptor status in breast tumors.

Mammaglobin (SCGB2A2) is a breast-specific member of the secretoglobin (SCGB) gene family. SCGB2A2 has previously been found overexpressed in breast tumors but possible associations between its expression and established prognostic tumor characteristics such as the levels of estrogen and progesterone receptors have not yet been investigated. We evaluated SCGB2A2 expression at the mRNA and at the protein level by reverse-transcription polymerase chain reaction and immunocytochemistry in 52 and 32 breast tumors, respectively. Both SCGB2A2 mRNA and protein expression were significantly higher in estrogen-receptor-positive compared to estrogen-receptor-negative tumors (Mann- Whitney rank sum test, p = 0.04; chi-square test, p = 0.01; respectively). In contrast, SCGB2A2 expression did not correlate with progesterone receptor levels or Nottingham grade. As estrogen and antiestrogen treatment of estrogen-positive breast cancer cell lines does not modify SCGB2A2 expression we suggest that SCGB2A2 may be a new independent breast cancer prognostic marker.