Assessing children's exposure to manganese in drinking water using a PBPK model

A previously published human PBPK model for manganese (Mn) in infants and children has been updated with Mn in drinking water as an additional exposure source. Built upon the ability to capture differences in Mn source-specific regulation of intestinal uptake in nursing infants who are breast-fed and formula-fed, the updated model now describes the bioavailability of Mn from drinking water in children of ages 0-18. The age-related features, including the recommended age-specific Mn dietary intake, age-specific water consumption rates, and age-specific homeostasis of Mn, are based on the available human data and knowledge of the biology of essential-metal homeostasis. Model simulations suggest that the impact of adding drinking-water exposure to daily Mn exposure via dietary intake and ambient air inhalation in children is not greater than the impacts in adults, even at a drinking-water concentration that is 2 times higher than the USEPA's lifetime health advisory value. This conclusion was also valid for formula-fed infants who are considered at the highest potential exposure to Mn from drinking water compared to all other age groups. Our multi-route, multi-source Mn PBPK model for infants and children provides insights about the potential for Mn-related health effects on growing children and will thereby improve the level of confidence in properly interpreting Mn exposure-health effects relationships in children in human epidemiological studies.

Effectiveness of an advanced practice nurse-led delirium education and training programme

AIM

To develop an education and training programme to enhance bedside nurses' knowledge, competency and compliance in accurately performing delirium screening in intensive care units.

BACKGROUND

Delirium in intensive care units is associated with several poor patient outcomes. Delirium detection can be improved by enhancing nurses' knowledge, competency and compliance in accurately performing delirium screening.

METHODS

A descriptive quantitative study with pretest-post-test design was adopted. There were 245 nurses from five intensive care units who participated in the study. Multiple-choice questions were used to assess nurses' knowledge change before and after the education programme. Competency was assessed before and 2 months after the programme by simulation with a standardized patient, followed by real patients at the bedside. Compliance data on screening were collected from the documentation of the Richmond Agitation-Sedation Scale and the Confusion Assessment Method for the ICU before and 3 and 10 months after the programme. Data collection took 1 year, from June 2014 to May 2015.

RESULTS

Despite nurses' improved knowledge and good competency, delirium screening documentations after 3 months were poor. However, screening documentations subsequently improved when measured at 10 months, following further emphasis by the senior nursing staff.

IMPLICATIONS FOR NURSING PRACTICE AND POLICY

Nursing administrators and bedside nurses need to be involved in the policy-making process and plan a training programme for the new nursing staff in the high-risk areas. A short refreshment course should be offered to the nursing staff 3 months after the initial training programme.

CONCLUSIONS

Improved knowledge and competency in assessment did not improve compliance and documentation of delirium screening. Therefore, it is important to reinforce nurses' compliance of delirium screening over time.

A Review of Magnetic Particle Imaging and Perspectives on Neuroimaging

Magnetic particle imaging is an emerging tomographic technique with the potential for simultaneous high-resolution, high-sensitivity, and real-time imaging. Magnetic particle imaging is based on the unique behavior of superparamagnetic iron oxide nanoparticles modeled by the Langevin theory, with the ability to track and quantify nanoparticle concentrations without tissue background noise. It is a promising new imaging technique for multiple applications, including vascular and perfusion imaging, oncology imaging, cell tracking, inflammation imaging, and trauma imaging. In particular, many neuroimaging applications may be enabled and enhanced with magnetic particle imaging. In this review, we will provide an overview of magnetic particle imaging principles and implementation, current applications, promising neuroimaging applications, and practical considerations.

Efficacy of needleless transcutaneous electroacupuncture in synchronization with breathing for symptomatic idiopathic gastroparesis: A blinded and controlled acute treatment trial

BACKGROUND

Needleless transcutaneous electroacupuncture (TEA) improves nausea and myoelectrical activity in diabetic gastroparesis (GP). Synchronized TEA (STEA), which combines synchronized breathing with TEA, is more potent than TEA in enhancing vagal activity in healthy subjects.

AIMS

To investigate whether STEA improves symptoms, electrogastrogram (EGG) and vagal activity in idiopathic gastroparesis (IGP).

METHODS

Eighteen IGP subjects underwent 2 randomized visits (sham at non-acupoints or real STEA at acupoints) consisted of a 30-minute baseline, an Ensure challenge to provoke nausea, followed by 60-minute treatment with sham or real STEA, and 15-minute observation period. Severity of nausea, EGG, and vagal activity (based on electrocardiogram and serum Pancreatic Polypeptide, PP) were recorded.

RESULTS

In sham or STEA, the nausea scores of 2.7 ± 0.5 and 1.9 ± 0.5 at fasting baseline, respectively, increased to 5.9 ± 0.4 and 5.8 ± 0.3 during Ensure test (P < .05, vs baseline), subsequently reduced to 3.4 ± 0.6 with sham or 3.6 ± 0.6 with STEA, respectively (P < .05, vs Ensure period). Experiments with sham and STEA started with similar % of normal waves on EGG (66.4 ± 3.9 and 61.8 ± 3.0, respectively); decreased to 63. 5 ± 4.1 and 58.2 ± 2.8 during the Ensure test. After STEA, there was ~24% increase in % of normal waves, significantly different from the sham (6.0%) (P < .01). In sham or STEA, vagal activity was identical at baseline and after the Ensure. STEA induced a 3-fold increase in vagal activity compared with sham (P < .01). Ensure increased serum PP levels, and both treatments decreased the PP CONCLUSIONS: In IGP, STEA is not superior to Sham in decreasing nausea, but is more effective in improving gastric dysrhythmia.

[Developing a Chinese PI-RADS v2-based nomogram for predicting clinically significant prostate cancer in patients with a prior negative biopsy]

Objective: To develop a nomogram based on prostate imaging reporting and data system version 2 (PI-RADS v2) to predict clinically significant prostate cancer in patients with a prior negative prostate biopsy. Methods: The clinical and pathological data of 231 patients who underwent repeat prostate biopsy and multiparametric MRI (mpMRI) were reviewed. Based on PI-RADS v2, the mpMRI results were assigned as PI-RADS grade from 0 to 2. A Logistic regression nomogram for predicting the probabilities of clinically significant prostate cancer were constructed. The performances of the nomogram were assessed using area under the receiver operating characteristic (ROC) curve, calibrations and decision curve analysis. Results: Of the total 231 repeat prostate biopsy patients, clinically significant prostate cancer was detected in 59 cases(25.5%). In multivariate Logistic regression analysis, age, prostate specific antigen (PSA), prostate volume (PV), digital rectal examination (DRE) and mpMRI results were significant independent predictors of the diagnosis of clinically significant prostate cancer (P<0.05). The nomogram with super predictive accuracy were constructed (AUC=0.927, P<0.001), and exhibited excellent calibration. Decision curve analysis also demonstrated a high net benefit across a wide range of threshold probabilities . Conclusions: PI-RADS v2 combined with age, PSA, PV and DRE can predict the probability of clinically significant prostate cancer in patients with negative initial biopsies. The nomogram generated may help the decision-making process in patients with prior benign histology before the performance of repeat biopsy.

Adiponectin: A prosurvival and proproliferation signal that increases bovine mammary epithelial cell numbers and protects them from endoplasmic reticulum stress responses

Cell-cell interactions between epithelial and stromal cells are predominant in the mammary gland, and various stromal cell-derived factors can elicit mitogenic responses in adjacent epithelial cells. Adiponectin is a hormone secreted mainly by adipocytes that mediates stromal-epithelial interactions in a number of tissues. Adiponectin receptors are expressed by bovine mammary epithelial cells, but the regulatory effects of adiponectin on the development and function of the mammary gland remain unclear. We therefore sought to investigate the effects of adiponectin on bovine mammary epithelial (MAC-T) cells and the regulatory mechanisms that underlie these adiponectin-induced actions. Our results revealed an increase in MAC-T cell proliferation and cell cycle progression in response to adiponectin. The expression of nuclear proliferating cell nuclear antigen (PCNA) and cyclin D1 was induced in MAC-T cells, and intracellular signaling molecules such as serine/threonine protein kinase (AKT), 70 kDa ribosomal S6 kinase (P70S6K), ribosomal protein S6 (S6), extracellular signal-regulated kinases 1 and 2 (ERK1/2), 90 kDa ribosomal S6 kinase (P90S6K), and cyclin D1 were activated in a dose-dependent manner. The abundance of adiponectin-induced signaling proteins was suppressed following inhibition of AKT or ERK1/2 mitogen-activated protein kinase (MAPK) signaling. In addition, inhibition of AKT or ERK1/2 signaling significantly reduced adiponectin-stimulated MAC-T cell proliferation. Furthermore, adiponectin reduced tunicamycin-induced expression and activation of endoplasmic reticulum stress-related proteins in MAC-T cells and attenuated the repressive effect of tunicamycin on proliferation of MAC-T cells. Collectively, these results suggest that adiponectin-mediated signaling may affect the development and function of the mammary gland in dairy cows by increasing mammary epithelial cell numbers. These findings may result in important implications for improving our fundamental understanding of lactation physiology in livestock species.

The functional effects and mechanisms by which fibroblast growth factor 2 (FGF2) controls bovine mammary epithelial cells: Implications for the development and functionality of the bovine mammary gland

Fibroblast growth factor (FGF) signaling plays essential roles in tissue development and homeostasis. Accumulating evidence reveals that fibroblast growth factor 2 (FGF2) regulates ductal elongation, which requires cell proliferation and epithelial expansion in the mammary gland. However, the function and mechanisms by which FGF2 controls functionality of epithelial cells is less well defined. Here, we demonstrate the functional effects of FGF2 on bovine mammary epithelial (MAC-T) cells and the intracellular signaling mechanisms for these FGF2-induced actions. The current results show that treatment of MAC-T cells with a recombinant FGF2 induced cell proliferation and cell-cycle progression with increased expression of proliferating cell nuclear antigen and cyclin D1. Moreover, FGF2 increased phosphorylation of serine/threonine protein kinase (protein kinase B [AKT]), extracellular signal-regulated kinases 1 and 2 (ERK1/2), Jun N-terminal kinase (JNK), 70 kDa ribosomal S6 kinase (P70S6K), 90 kDa ribosomal S6 kinase (P90S6K), ribosomal protein S6 (S6), and cyclin D1 proteins. These FGF2-induced activations of signaling pathway proteins were inhibited by blocking AKT, ERK1/2, or JNK phosphorylation. The effect of FGF2 to stimulate MAC-T cell proliferation was mediated by activation of FGF receptors (FGFR) and AKT, ERK1/2, and JNK mitogen-activated protein kinase pathways in response to FGF2 stimulation. Furthermore, expression and activation of endoplasmic reticulum (ER) stress-related factors and ER stress-induced MAC-T cell death was reduced by FGF2. Together, these results suggest that the FGF2-FGFR-intracellular signaling cascades may contribute to maintaining and/or increasing numbers of mammary epithelial cells by inducing proliferation of mammary epithelial cells and by protecting cells from ER stress responses. Therefore, this study provides evidence that FGF2 signaling is a positive factor for mammary gland remodeling and for increasing persistency of milk production.

Dicer1, AGO3, and AGO4 microRNA machinery genes are differentially expressed in developing female reproductive organs and overexpressed in cancerous ovaries of chickens

MicroRNA (miRNA)-mediated gene silencing is a key mechanism regulating numerous biological processes such as development of organs and tumorigenesis. The expression of miRNA machinery genes linked to miRNA biogenesis and processing is finely regulated. Despite accumulating evidence for chicken miRNA in the female reproduction system, precise regulatory mechanisms are largely unknown. Therefore, the objective of this study was to determine changes in expression levels of miRNA machinery genes in developmental stages of the oviduct and ovarian carcinogenesis of laying hens. In the present study, differential expression of miRNA machinery genes during ovarian carcinogenesis was determined using cancerous and normal ovaries collected from normal laying hens and hens with cancer. Our results showed that 3 miRNA machinery genes (, , and ) were differentially expressed as laying hens' reproductive organs developed. These genes were simultaneously upregulated in cancerous ovaries compared with those in normal ovaries. Their transcripts were abundantly localized in glandular epithelial cells of cancerous ovaries. Our results indicate that , , and play critical roles in the development of reproductive organs and ovarian carcinogenesis in laying hens, suggesting that simultaneous overexpression of these genes might serve as a prognostic factor for ovarian cancer.

Differential expression of neuregulin 1 (NRG1) and candidate miRNA regulating NRG1 transcription in the chicken oviduct in response to hormonal changes

Neuregulin 1 (NRG1), a signaling protein that binds to members of the erythroblastoma (ErbB) family, is known to play essential biological roles in mediating cell-cell interactions and orchestrating vital cell functions in the heart and nervous system. NRG1 is closely associated with developmental processes in various organs and expression of several NRG1 isoforms are regulated by estrogen. However, expression and its hormonal regulation during development of the female reproductive tract remain unknown. The reproductive system of chickens undergoes dynamic morphological and functional changes in response to estrogen and the molting process. Therefore, in the current study, we found differential expression of and candidate microRNA regulating chicken transcription in response to estrogen stimulation and/or the molting process. The results revealed that relative expression of mRNA increased in the oviducts of chicks treated with diesthylstilbestrol (DES; a synthetic non-steroidal estrogen). Additionally, abundant NRG1 mRNA expression was primarily in the glandular (GE) and luminal (LE) epithelia of the magnum in the developing chick oviduct in response to exogenous estrogen. Also, expression decreased during regression of the oviduct following induced molting by feeding high levels of zinc in the diet, and then gradually resurged as the oviduct underwent remodeling and recrudescence in laying hens. In addition, the present results revealed changes in relative expression of candidate chicken microRNA (, and ) targeting transcription in chicken oviducts in response to exogenous estrogen. In conclusion, these results provide the first evidence that is a novel estrogen-responsive gene closely correlated with the estrogen-dependent development of the oviduct of chicks and regeneration of the oviduct after molting. Further, regulation of expression involving at least 3 chicken miRNA is likely a prerequisite for those estrogen regulated developmental events.

[Development of a Chinese nomogram based on muti-parametric magnetic resonance for predicting the probability of prostate cancer in patients after initial negative biopsy]

Objective: To develop a predictive nomogram based on multi-parametric magnetic resonance imaging (mpMRI) information to identify men more likely to have a cancer diagnosed on repeat prostate biopsy. Methods: The clinical data of 237 patients who received repeat prostate biopsy after initial negative biopsy from Department of Urology of Peking University First Hospital between January 2001 and August 2016 was reviewed. Patient age, body mass index (BMI), serum total prostate-specific antigen (PSA), percent free PSA (f/t), prostate volume (PV), PSA density (PSAD), PSA velocity (PSAV), digital rectal examination (DRE), transrectal ultrasound (TRUS)and mpMRI results were included in the univariate and multivariate analysis. A nomogram was developed using selected variables and the area under the receiver operating characteristic (ROC) curve was calculated as a measure of discrimination. Results: A total of 76 patients (32.07%) had prostate cancer (PCa) detected on repeat biopsy. Based on univariate and multivariate logistic regression analysis, the patient age, PSA, PV, DRE and mpMRI results were independent predictors for the diagnosis of PCa on repeat biopsy. The current nomogram performed well (AUC=0.910) and showed excellent calibration. Conclusions: Multi-parametric magnetic resonance imaging combined with age, PSA, PV and DRE can predict the probability of PCa in patients with initial negative biopsy. The nomogram might help in decision-making for men with prior benign histology before the performance of repeat biopsy.

Increase of Cr solubility in cubic Sr2FexCr2−xO6−y unit cell using sol–gel assisted synthesis and characterizations of Sr2FeCrO6−y phase

A homogeneous, non-selective chelating system using EDTA–chitosan was created to produce a cubic phase perovskite material Sr₂FeCrO_6−y.

Bacterial diversity and community structure during fermentation of Chinese sauerkraut with Lactobacillus casei 11MZ-5-1 by Illumina Miseq sequencing

The bacterial diversity and community structure involved in Chinese sauerkraut is one of the most important factors shaping the final characteristics of traditional foods. In this research, Lactobacillus casei 11MZ-5-1 was applied in Chinese sauerkraut fermentation as a starter culture. Illumina Miseq sequencing analysis was used to reveal the bacterial diversity and community structure during Chinese sauerkraut fermentation. A total of 177 283 high-quality reads of 16S rRNA V4 regions were obtained. The inoculation of L. casei 11MZ-5-1 decreased considerably the bacterial richness and bacterial diversity. This inoculum led to the replacement of Lactococcus by Lactobacillus. The levels of Pseudomonas and Enterobacter bacteria decreased. These findings reveal the evolution of important bacterial groups that are involved in fermentation and will facilitate improvements in the Chinese sauerkraut fermentation process.

SIGNIFICANCE AND IMPACT OF THE STUDY

This research thoroughly revealed the effects of Lactobacillus casei 11MZ-5-1 starter cultures on bacterial communities during Chinese sauerkraut fermentation. Illumina Miseq sequencing was effective technique to monitor the bacterial diversity and community structure. The inoculation of L. casei 11MZ-5-1 led to the decline of bacterial richness and diversity together with a consistent predominance of Lactobacillus during spontaneous fermentation. The result collectively suggested L. casei 11MZ-5-1 is a promising starter in Chinese sauerkraut manufacturing.

Development of an XBP1 agonist, HLJ2, as a potential therapeutic agent for ulcerative colitis

There is a severe lack of effective treatments for ulcerative colitis (UC), a recurrent and intractable inflammatory bowel disease. The identification of valid targets and new drugs is an urgent need. In this study, we identified the XBP-1 agonist HLJ2 as a promising treatment candidate. In an in vivo mouse model of DSS-induced colitis, HLJ2 decreased weight loss, colon contracture, disease activity index (DAI), colon mucosa damage index (CMDI) and histopathological index (HI). HLJ2 also decreased myeloperoxidase (MPO) activity and reduced production of the inflammatory cytokines TNF-α, IL-1β, and IL-6. HLJ2 improved intestinal mucosa damage induced by dextran sodium sulfate (DSS) and increased the expression of ZO-1 and claudin-1. Fecal 16s rRNA high-throughput sequencing demonstrated a significant improvement in UC intestinal dysbacteriosis in mice treated with HLJ2, including increased abundance of probiotics such as Lachnospiraceae, Prevotellaceae, and Lactobacillaceae. At the same time there was a reduction in the abundance of pathogenic or conditional pathogenic microorganisms such as Bacteroidaceae, Porphyromonadaceae, Deferribacteraceae, and Pseudomonadaceae in HLJ2-treated mice compared with untreated mice. Our results demonstrated that the XBP1 agonist HLJ2 inhibits inflammation, regulates the intestinal flora, and protects the intestinal mucosa. It is thus a potential therapeutic agent for ulcerative colitis.

Rapid Communication: MicroRNA co-expression network reveals apoptosis in the reproductive tract during molting in laying hens

The aim of this study was to determine the regulatory mechanisms of molting and recrudescence via studying the micro-RNA (miRNA) expression in the oviduct of laying hens. We performed a cDNA microarray analysis in the magnum tissue from the oviduct to identify the whole miRNA profiles through the molting and recrudescence periods. A total of 35 laying hens (47-wk-old) were divided into 7 groups (0 d: a control group; 6 and 12 d: 2 molting-period groups fed on a high-zinc diet; and 20, 25, 30, and 35 d: 4 recrudescence-period groups fed on a normal diet after a 12-d period on a high-zinc diet). An miRNA co-expression network (miRCN) was generated using the differentially expressed miRNA (DEM) according to the entire data integration. The significantly co-expressed miRNA ( = 111) were highly differentially expressed from 12 to 20 d, which was a transition period between molting and recrudescence, while their expression patterns were contrary to the estrogen changes. The targets of highly connected miRNA ( = 12) indicated the significant biological pathways and gene ontology (GO) terms, such as MAPK and Wnt signaling and magnesium-ion binding, which are associated with apoptotic activities. These results suggest that the miRNA of the miRCN might play a role in the apoptotic progression of the reproductive tract during molting.

Colitis Is Effectively Ameliorated by (±)-8-Acetonyl-dihydrocoptisine via the XBP1-NF-κB Pathway

Ulcerative colitis (UC) is a recurrent, chronic intestinal disease. Available treatments for UC are poor effective and/or cause severe adverse events. X-box binding protein 1 (XBP1) and nuclear factor-κB (NF-κB) have been reported to play important roles in UC. Specifically, deletion or downregulation of XBP1 leads to spontaneous enteritis and results in imbalanced secretion of NF-κB and other proinflammatory cytokines. (±)-8-acetonyl-dihydrocoptisine, i.e., (±)-8-ADC, is a monomer semi-synthesized from coptisine. In vitro, (±)-8-ADC activated the transcriptional activity of XBP1, inhibited expression of NF-κB, and reduced production of proinflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β), in lipopolysaccharide-stimulated IEC6 cells. Therefore, silencing XBP1 would reduce the inhibition effect of (±)-8-ADC on NF-κB expression and the cytokines secretion in vitro. In a dextran sulfate sodium-induced colitis mouse model, oral administration of (±)-8-ADC ameliorated weight loss and colon contracture, and decreased the average disease activity index score and pathological damage. Simultaneously, (±)-8-ADC also increased XBP1 expression, and decreased NF-κB expression and secretion of myeloperoxidase, TNF-α, IL-6 and IL-1β in the colon. Therefore, (±)-8-ADC may ameliorate UC via the XBP1-NF-κB pathway and should be considered as a therapeutic candidate for UC.

[Percutaneous biopsy of the renal masses under ultrasound: a single-center 14 years experience]

OBJECTIVE

To assess the diagnostic rate, safety and clinical application of percutaneous renal masses biopsy for advanced renal cell carcinoma patients.

METHODS

In this retrospective study, we collected the data of renal masses from the patients who underwent renal masses biopsy under ultrasound from April 2001 to December 2014 in Peking University First Hospital. A total of 75 patients who were undiagnosed or diagnosed with advanced renal cell carcinoma by the imageological method were enrolled in this study. The patient and lesion characteristics such as tumor size, pathology of tumor, histologic subtype, pathological grade, biopsied location and biopsied cores were recorded and analyzed.

RESULTS

Among all the 75 patients, biopsy was diagnostic in 64 cases (85.3%) and non-diagnostic in 11 cases (14.7%). Of the 64 diagnostic biopsies, 60 were malignant, including 37 (61.7%) renal cell carcinoma (RCC), 13 (21.7%) urothelial carcinoma and 10 (16.7%) other malignant masses. Of all the RCC subjects, 24 suffered from clear cell RCC, 5 papillary RCC, 3 collecting duct carcinomas, 1 unclassified RCC and 4 unknown subtypes. The 11 non-diagnostic biopsied samplings included inflammatory, blood and extrarenal tissue and normal renal tissue. The proportion of collecting duct carcinoma in RCC was 10.8% and the proportion of squamous carcinoma in urothelial carcinoma was 23.1%, which were both higher than the previous research findings. For the male and female groups, non-diagnostic yields were 6.5% and 30.4%, respectively (P=0.022). Of all the 75 patients, 13 renal cell carcinoma patients underwent the surgical treatment and got the results of postoperative pathology. Comparing preoperative biopsy pathological diagnosis with postoperative pathological diagnosis, we found the diagnostic correct rates for benign and malignant lesions, pathological subtype and pathological grade were 100%, 81.8% and 60%, respectively. Mild macroscopic hematuria occurred in 1 case after RMB and there were no serious complications in all the cases.

CONCLUSION

Percutaneous renal masses biopsy under ultrasound with a high diagnostic rate which can define the histologic subtype of renal cell carcinoma. With targeted therapy, more and more patients whose evaluation suggests local advanced disease or metastatic tumors adopt renal tumor biopsy to define the histologic subtype, which could avoid unnecessary surgical treatment.

[Predictive factor analysis of time to progression of castration-resistant prostate cancer after androgen deprivation therapy]

OBJECTIVE

To explore risk factors including prostate-specific antigen (PSA) kinetics for the prediction of castration-resistant prostate cancer (CRPC), and to build a practical model for predicting the progression to CRPC after androgen deprivation therapy (ADT) so as to facilitate clinicians in decision-making for prostate cancer patients receiving ADT.

METHODS

A total of 185 patients with prostate cancer who had received ADT as the primary therapy in Department of Urology of Peking University First Hospital from 2003 to 2014 were enrolled retrospectively. All the patients were diagnosed with prostate cancer via prostate biopsy and followed up every four weeks from the initiation of ADT. All the patients received ADT with luteinizing hormone-releasing hormone agonists (LHRH-A) or surgical castration accompanied with an antiandrogen (bicalutamide or flutamide, combined androgen blockade). The clinical information of the patients were collected including age, clinical TNM stage, Gleason score (GS), risk groups of prostate cancer, PSA at the initiation of ADT, PSA nadir after ADT, PSA decline velocity, and the time to PSA nadir. The end point of this study was the diagnosis of CRPC, which was based on the European Association of Urology (EAU) Guideline 2016. Cox proportional hazards regression models were established to analyze and estimate their effects on the time of progression to CRPC.

RESULTS

In this study, 185 patients with prostate cancer who had received ADT as the primary therapy were included. The mean age was (71.02±8.67) years. The median time to progression to CRPC in this cohort was 38 months (ranging from 4 to 158 months). On univariate analysis, we found clinical T stage, N stage, the metastasis state before ADT, risk groups of prostate cancer, PSA decline velocity, and PSA nadir were all related to the time to CRPC progression, P<0.01 for all the above variables. And on multivariate analysis, the presence of distant metastasis before ADT (HR=6.030, 95% CI: 3.229-11.263, P=0.001), higher PSA nadir (HR=1.185, 95% CI: 1.080-1.301, P=0.001), higher PSA decline velocity>11 μg/(L×month) (HR=2.124, 95% CI: 1.195-3.750, P=0.001), and time to PSA nadir ≤9 months (HR=3.623, 95% CI: 1.640-4.817, P=0.004) were found to be significantly associated with an increased risk of progression to CRPC.

CONCLUSION

Patients with rapid decreasing of PSA in the initial ADT were more likely to progress to CRPC.

Extracellular diffusion quantified by magnetic resonance imaging during rat C6 glioma cell progression

Solution reflux and edema hamper the convection-enhanced delivery of the standard treatment for glioma. Therefore, a real-time magnetic resonance imaging (MRI) method was developed to monitor the dosing process, but a quantitative analysis of local diffusion and clearance parameters has not been assessed. The objective of this study was to compare diffusion into the extracellular space (ECS) at different stages of rat C6 gliomas, and analyze the effects of the extracellular matrix (ECM) on the diffusion process. At 10 and 20 days, after successful glioma modeling, gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) was introduced into the ECS of rat C6 gliomas. Diffusion parameters and half-life of the reagent were then detected using MRI, and quantified according to the mathematical model of diffusion. The main ECM components [chondroitin sulfate proteoglycans (CSPGs), collagen IV, and tenascin C] were detected by immunohistochemical and immunoblot analyses. In 20-day gliomas, Gd-DTPA diffused more slowly and derived higher tortuosity, with lower clearance rate and longer half-life compared to 10-day gliomas. The increased glioma ECM was associated with different diffusion and clearance parameters in 20-day rat gliomas compared to 10-day gliomas. ECS parameters were altered with C6 glioma progression from increased ECM content. Our study might help better understand the glioma microenvironment and provide benefits for interstitial drug delivery to treat brain gliomas.