Dynamics of the Deformable Fluid Interface Interacting with an Approaching Solid under the Electrostatic Field

A theoretical model was developed to describe the dynamics of a deformable fluid interface interacting with an approaching solid without contact by both the attractive electrostatic and van der Waals (i.e., vdW) interaction, analogous to the situation in the experiments by electric force microscopy (i.e., EFM) or electric-surface force apparatus (i.e., E-SFA) involved in the soft fluid interface. On the basis of this model, a numerical study of the deformation of the fluid interface, the force-vs-separation behavior, and the critical limiting conditions of contact has systematically been carried out. Our results show that the surface pressure induced by the electrostatic interaction plays a more prominent role in the deformation of the fluid interface than the vdW interaction does, and there exists a principal length scale associated with the relative strength of the electrostatic field to the surface tension, affecting the fluid interface shape under the electrostatic field. It was also shown that both the force-distance curves and the corresponding curves of fluid interface deformation peak versus distance for various electrostatic fields satisfy the universal scaling power law. Moreover, an analytical solution to the Euler-Lagrange differential equation governing the deformation of the fluid interface under the external electric field is obtained, and two extended formulas for explicitly describing the principal length scales that respectively characterize the lateral and longitudinal deformations of the fluid interface were determined.

Combined effect of ozone and household air pollution on COPD in people aged less than 50 years old

OBJECTIVES

Air pollution has been suggested as an important risk factor for chronic obstructive pulmonary disease (COPD); however, evidence of interactive effects on COPD between different factors was sparse, especially for young adults. We aimed to assess the combined effects of ambient ozone (O3) and household air pollution on COPD in young individuals.

METHODS

We conducted a population-based study of residents aged 15-50 years in the low-income and middle-income regions of western China. We used multivariable logistic regression models to examine the associations between long-term ozone exposure and COPD in young individuals.

RESULTS

A total of 6537 young cases were identified among the participants, with a COPD prevalence rate of 7.8 (95% CI 7.2% to 8.5%), and most young COPD individuals were asymptomatic. Exposure to household air pollution was associated with COPD in young patients after adjustment for other confounding factors (OR 1.82, 95% CI 1.41 to 2.37). We also found positive associations of COPD with O3 per IQR increase of 20 ppb (OR 1.92, 95% CI 1.59 to 2.32). The individual effects of household air pollution and O3 were 1.68 (95% CI 1.18 to 2.46) and 1.55 (95% CI 0.99 to 2.43), respectively, while their joint effect was 3.28 (95% CI 2.35 to 4.69) with the relative excess risk due to interaction of 1.05 (95% CI 0.33 to 1.78).

CONCLUSIONS

This study concludes that exposure to ambient O3 and household air pollution might be important risk factors for COPD among young adults, and simultaneous exposure to high levels of the two pollutants may intensify their individual effects.

Ambient particulate matter associates with asthma in high altitude region: A population-based study

Background

Exposure to particulate matter (PM) has been a major public health threat, but the potentially differential effects on asthma of PM remain largely unknown in high altitude settings. We evaluated the effects of ambient PM on asthma in high altitude settings.

Methods

The study recruited a representative sample from high altitude settings using a multistage stratified sampling procedure. Asthma was defined by a self-reported history of diagnosis by a physician or by wheezing symptoms in the preceding 12 months. The annual mean PM_2.5 and PM₁₀ concentrations were calculated for each grid cell at 1-km spatial resolution based on the geographical coordinates.

Results

We analyzed data for participants (mean age 39.1 years, 51.4% female) and 183 (3.7%, 95% confidence interval (CI): 3.2-4.2) of the participants had asthma. Prevalence was higher in women (4.3%, 95% CI 3.5-5.1) than in men (3.1%, 2.4-3.8) and increasing with higher concentration of PM exposures. For an interquartile range (IQR) difference (8.77 μg/m³) in PM_2.5 exposure, the adjusted odds ratio (OR) was 1.64 (95% CI 1.46-1.83, P < 0.001) for risk of asthma. For PM₁₀, there was evidence for an association with risk of asthma (OR 2.34, 95% CI: 1.75-3.15, P < 0.001 per IQR of 43.26 μg/m³). Further analyses showed that household mold or damp exposure may aggravate PM exposure associated risks of asthma.

Conclusions

This study identified that PM exposure could be a dominate environmental risk factor for asthma but largely unconsidered in the high-altitude areas. The association between PM exposure and asthma should be of interest for planners of national policies and encourage programs for prevention of asthma in residents living at high altitudes.

Plasmapheresis compared with conventional treatment for hypertriglyceridemia-induced acute pancreatitis: A systematic review and meta-analysis

BACKGROUND

The treatment of acute pancreatitis (AP) induced by hypertriglyceridemia (HTG) remains controversial with regard to plasmapheresis vs conventional treatment. We reviewed relevant articles to explore the efficacy of plasmapheresis in the management of HTG-induced AP.

METHODS

We systematically reviewed studies that compared plasmapheresis with conventional treatment for HTG-induced AP using three databases: PubMed, Embase, and Cochrane Library, as well as relevant references. The primary outcomes were 24 h triglyceride reduction rate and in-hospital mortality.

RESULTS

A total of 791 articles were retrieved. Finally, 15 observational studies (1080 participants) were included, most of which were historical cohort studies. Compared with conventional treatment, plasmapheresis assisted in the reduction of serum triglyceride (TG) levels in the first 24 h after hospital admission (standardized mean difference [SMD]: 0.58; 95% confidence interval [CI]: 0.17 to 0.99; P = 0.005). However, it resulted in increased hospitalization costs (thousand yuan) (weighted mean difference [WMD]: 24.32; 95% CI: 12.96 to 35.68; P < 0.001). With regard to in-hospital mortality, although the mortality rate in the plasmapheresis group was higher than that in the conventional treatment group (relative risk [RR]: 1.74; 95% CI: 1.03 to 2.94; P = 0.038), the result was disturbed by confounding factors as per the subgroup and sensitivity analysis, as well as trial sequential analysis (TSA). No significant differences were found in other outcomes, including systematic complications, local complications, the requirement for surgery, and hospitalization duration.

CONCLUSION

The effect of plasmapheresis in HTG-induced AP is not superior to that of conventional treatment, even resulting in a greater economic burden to patients and health care system. High quality randomized control trials are required to obtain a more a definitive understanding of this issue.

[Effects of extramedullary disease on patients with newly diagnosed multiple myeloma]

Objective: To summarize the characteristics of patients with newly diagnosed multiple myeloma (NDMM) admitted at Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine. We compared the clinical characteristics and prognoses among patients with non-extramedullary disease (EMD), bone-related extramedullary (EM-B) disease, and extraosseous extramedullary (EM-E) disease and further explored the effects of autologous hematopoietic stem cell transplantation (ASCT) for EMD. Methods: From January 2015 to January 2022, data of 114 patients (22%) with EMD out of 515 patients with NDMM were retrospectively analyzed; 91 (18%) and 23 (4%) patients comprised the EM-B and EM-E groups, respectively. The clinical characteristics of patients in all groups were compared with the Chi-square test. Progression-free survival (PFS) and overall survival (OS) of patients were analyzed by the Kaplan-Meier method. Independent prognostic factors were determined using multivariate Cox proportional hazard model. Results: There were no significant differences in age, gender, ISS stage, light chain, creatinine clearance, cytogenetic risk, 17p deletion, ASCT, and induction regimens among the three groups. Overall, 13% of EM-E patients had IgD-type M protein, which was significantly higher than that in EM-B patients (P=0.021). The median PFS of patients in the non-EMD, EM-B, and EM-E groups was 27.4, 23.1, and 14.0 months; the median OS was not reached, 76.8 months, and 25.6 months, respectively. The PFS (vs non-EMD, P=0.004; vs EM-B, P=0.036) and OS (vs non-EMD, P<0.001; vs EM-B, P=0.002) were significantly worse in patients with EM-E, while those were not significantly different between patients with EM-B and those with non-EMD. In the multivariate analysis, EM-E was an independent prognostic factor for OS in patients with NDMM (HR=8.779, P<0.001) and negatively impacted PFS (HR=1.874, P=0.050). In those who did not undergo ASCT, patients with EM-B had significantly worse OS than those with non-EMD (median 76.8 months vs. not reached, P=0.029). However, no significant difference was observed in the PFS and OS of patients with EM-B and those with non-EMD who underwent ASCT. Conclusions: Compared to patients with either non-EMD or EM-B, those with EM-E had the worst prognosis. EM-E was an independent risk factor for OS in patients with NDMM. ASCT can overcome the poor prognosis of EM-B.

[Improving the vaccination rate of patients with chronic obstructive pulmonary disease-getting started with clinicians]

Infection of influenza virus or Streptococcus pneumoniae is the important causes of acute exacerbation of chronic obstructive pulmonary disease(COPD) and death, resulting in huge burden of medical costs. Although the guidelines at all levels generally recommend vaccination against influenza and pneumonia, the vaccination rate in China is not satisfactory. The main reasons include the limitations of economic, geographical and time constraints, as well as the influence of various socio-psychological factors and the fear of exacerbating the disease due to influenza vaccine and so on. We need start with clinicians, pay attention to the interaction of various influencing factors, to promote the integration of researchers in clinical medicine and preventive medicine, and make comprehensive consideration in the epidemic prevention strategy, which will help to adopt multi-mode methods to improve vaccination coverage and finally achieve a healthy life of patients with COPD.

Solid Fuel Exposure and Chronic Obstructive Pulmonary Disease in Never-Smokers

Background: Chronic obstructive pulmonary disease (COPD) is a public health challenge globally. The burden of COPD is high in never-smokers but little is known about its causes. We aimed to find the prevalence and correlates of COPD in never-smokers, with a special focus on solid fuel exposure.

Methods: We conducted a cross-sectional study in Western China. COPD was defined by FEV1/FVC < lower limits of normal (LLN). Descriptive statistics and multivariable logistic regression were used for analyses.

Results: Six thousand two hundred and seventy one patients were enrolled between June 2015 and August 2016. The prevalence of COPD in never-smokers was 15.0% (95% confidence interval 14.1–15.9). The common independent predictors of COPD in never-smokers included age ≥60 years, exposure to solid fuel, living in a rural area and a history of tuberculosis. Participants with solid fuel exposure were 69% more likely to have COPD (adjusted odds ratio 1.69, 95% CI 1.41–2.04) than those without such exposure. In addition, we found a positive association between small airway dysfunction and solid fuel exposure (OR 1.35, 95% CI 1.18–1.53).

Conclusions: This study confirmed the substantial burden of COPD among never-smokers and also defined the risk factors for COPD in never-smokers. Furthermore, we found a positive association between solid fuel exposure and COPD or small airway dysfunction.

Weekly pattern of dialysis unit blood pressure is a promising marker for prognosis evaluation in hemodialysis population

BACKGROUND

Dialysis unit blood pressure (BP) pattern showed superiority in prognostic evaluation and interdialytic BP burden assessment. However previous studies mainly focused on the recurrent BP pattern within a session (intradialytic BP change or intradialytic BP slope), the clinical value of the weekly pattern of dialysis unit BP is unknown.

METHODS

We performed a prospective cohort study in adult end stage renal disease (ESRD) patients on thrice weekly hemodialysis (HD). The slope and the change of the postdialysis systolic BP (SBP) in the course of a week (post-SBP slope and post-SBP change) were used to characterize the weekly pattern of dialysis unit BP. Outcomes included all-cause mortality, cardiovascular mortality, and first cardiovascular event. We also measured the home BP in our cohort.

RESULTS

One hundred and twenty-nine subjects were followed over a median of 31 months. Higher post-SBP slope (≥0.185) was independently associated with increased risk of all-cause mortality, cardiovascular mortality, and first cardiovascular event. Results were similar for increased post-SBP change. HD patients with a higher post-SBP slope or an increased post-SBP change also had significant increased interdialytic BP burden measured by home SBP on both dialysis days and non-dialysis days.

CONCLUSIONS

Post-SBP slope and post-SBP change might be promising dialysis unit BP markers for prognostic evaluation and interdialytic BP burden assessment.

532 nm green-light laser vaporization of upper tract urothelial carcinoma

Background

Endoscopic management of low risk upper tract urothelial carcinoma (UTUC) may be considered in select clinical scenarios, which allows sparing the morbidity of radical nephroureterectomy while achieving acceptable oncological outcomes and preservation of kidney function. Herein, we present a case with UTUC in a solitary kidney managed with 532 nm laser vaporization through a percutaneous approach.

Case presentation

The patient in this video (Additional file 1) is an 85-year-old woman who presented with a bulky tumor in the collecting system of a congenital solitary left kidney, which was a biopsy proven low grade urothelial carcinoma. Prior to the procedure, a lower pole percutaneous nephrostomy tube was successfully placed under sedation by Interventional Radiology. The procedure was done in a prone split leg position. The mass, which was predominantly localized to the renal pelvis was efficiently vaporized with the 532 nm laser in a systematic manner with continuous irrigation of normal saline through the cystoscope. The patient was discharged home on postoperative day 2 with the nephroureterostomy catheter open to drainage. This catheter was subsequently clamped and removed two weeks later without complications. Follow up uretroscopy showed excellent treatment response and the patient remains well without complications.

Conclusion

This case report details the potential utility of 532 nm laser vaporization of UTUC, however, ongoing studies are required to demonstrate peri-operative safety and durable oncologic efficacy.

Peridialysis BP levels and risk of all-cause mortality: a dose-response meta-analysis

Blood pressure (BP) management posed great challenge in hemodialysis (HD) population. We conducted a dose-response meta-analysis to investigate the quantitative features and the potential threshold effect of the associations between peridialysis BP levels and all-cause mortality risk in HD population. We searched all of the prospective cohort studies (published before 18 March 2017) on the associations between peridialysis BP levels and all-cause mortality risk. A total of 229,688 prevalent HD patients from 8 studies were included. Significant non-linear associations were noted between peridialytic BP levels and all-cause mortality risk. Significant increased risk of death was found in four peridialysis BP ranges, that is, low levels of predialysis SBP (<135 mmHg, 140 mmHg as the reference), two extremes of predialysis DBP (<55 and >95 mmHg, 90 mmHg as the reference), high levels of postdialysis SBP (>180 mmHg, 130 mmHg as the reference), and low levels of postdialysis DBP (<75 mmHg, 80 mmHg as the reference). Threshold effect was determined in the associations between peridialysis BP and all-cause mortality risk, and potential BP thresholds were identified (149 mmHg for predialysis SBP, 79 mmHg for predialysis DBP, 147 mmHg for postdialysis SBP and 76 mmHg for postdialysis DBP). In conclusion, the proposed peridialysis BP ranges and the threshold values could help clinicians identify high risk HD patients. The interpretation of the peridialysis BP mortality associations should be based on the features of HD population (especially the cardiovascular conditions, volume status and the dialysis vintage).

[Value of forced expiratory volume in 6 seconds (FEV(6)) in the evaluation of pulmonary function in Chinese elderly males]

Objective: To evaluate the value of forced expiratory volume in 6 seconds (FEV(6)) in the evaluation of pulmonary function in Chinese elderly males. Methods: Pulmonary function tests of elderly who had received regular physical examination in Beijing Hospital from July 2003 to April 2015 were analyzed on subjects with the following characteristics: aged 60 years or older, completion of bronchial dilation test and able to exhale for at least six seconds. The included subjects were divided into 2 groups: 60-<80 years group and ≥80 years group. The association of FEV(6) with forced vital capacity (FVC), FEV(1)/FEV(6) with FEV(1)/FVC, the diagnostic efficiency and influencing factor of FEV(6) and FEV(1)/FEV(6) were analyzed; the value of FEV(6) in the evaluation of pulmonary function in the study population was evaluated. Results: A total of 475 elderly men aged 60 years or older were enrolled, with a mean age of (77.13±9.53) years. Totally there were 269 subjects in 60-<80 years group, which accounted for 56.6%; 206 subjects were in ≥80 years group, which accounted for 43.4%. There were 292 subjects with irreversible airflow obstruction, accounting for 61.5%. In all the included subjects, FEV(6) was significantly correlated with FVC and post-bronchodilator FEV(1)/FEV(6) was significantly correlated with post-bronchodilator FEV(1)/FVC(r=0.971, 0.978; both P<0.001), which were similar in 60-<80 years group and ≥80 years group (r=0.967, 0.974 and r=0.955, 0.967; all P<0.001). FEV(1)/FEV(6) showed excellent accuracy in diagnosing airflow obstruction[area under curve (AUC)=0.990(95%CI: 0.983-0.996); P<0.001]. Using FEV(1)/FVC<0.70 as a reference, FEV(1)/FEV(6)<0.73 had the best sensitivity (0.952) and specificity (0.945), and there was excellent agreement between the two diagnostic cutoffs (κ=0.891; P<0.001). When difference between before and after bronchial dilation test was analyzed, no correlation was observed between FEV(6) improvement and the improvement of forced expiratory time (r=0.089; P=0.053), but FVC improvement was significantly correlated with the improvement of forced expiratory time (r=0.460; P<0.001). Similar results were also found in subjects with irreversible airflow obstruction. Subjects with FEV(1)/FEV(6)≥0.70 and FEV(1)/FVC<0.70 were categorized as pulmonary function middle group, a total of 73 cases, which included 20 cases ≥80 years old. The proportion of middle group among ≥80 years group was significantly less than that of the 60-<80 years group (χ(2)=8.958; P=0.003). In pulmonary function middle group, FEV(1)/FEV(6) or FEV(1)/FVC had no correlation with inspiratory capacity or residual volume/total lung capacity (all P>0.05). Conclusions: FEV(6) and FEV(1)/FEV(6) are strongly correlated with FVC and FEV(1)/FVC, and there is excellent agreement between FEV(1)/FEV(6) and FEV(1)/FVC. FEV(6) is simple, easy to operate and with less influencing factors, which can be used as a valid alternative for FVC in diagnosing airflow obstruction in elderly males.

mROS-TXNIP axis activates NLRP3 inflammasome to mediate renal injury during ischemic AKI

Ischemia/reperfusion (I/R) is a critical risk factor for acute kidney injury (AKI). Recent studies provided evidence that tubular epithelial cells (TEC)-associated inflammation aggravates kidney injury and impairs tissue repair after I/R injury. Here we demonstrated that the Nod-like receptor protein 3 (NLRP3) inflammasome is activated by mitochondrial reactive oxygen species (mROS) during I/R injury via direct interactions between the inflammasome and thioredoxin-interacting protein (TXNIP). Firstly, we found that NLRP3 inflammasome activation was induced by I/R injury, peaking at day 3 after reperfusion. Consistent with this observation, NLRP3 deletion significantly attenuated I/R-induced kidney damage and markers of inflammasome activation. Then, we observed mitochondrial dysfunction, characterized by ultrastructural changes and cytochrome C (Cyt c) redistribution. Mitochondria-targeted antioxidant MitoTEMPO prevented mROS overproduction and the decline in mitochondrial membrane potential (MMP) in vitro. MitoTEMPO treatment also inhibited NLRP3 inflammasome activation and co-localization of NLRP3 and TXNIP after simulated ischemia/reperfusion (SI/R) injury. Finally, we transfected HK-2 cells with TXNIP siRNA to explore the role of TXNIP in mROS-induced NLRP3 inflammasome activation. We found that TXNIP siRNA significantly inhibited NLRP3 inflammasome activation. These results demonstrate that NLRP3 inflammasome is activated through the mROS-TXNIP-NLRP3 pathway and provide a potential therapeutic target in ischemic AKI.

Hydroxychloroquine attenuates renal ischemia/reperfusion injury by inhibiting cathepsin mediated NLRP3 inflammasome activation

Inflammation is a major contributor to the pathogenesis of ischemic acute kidney injury (AKI), which complicates the post-operative outcomes of large numbers of hospitalized surgical patients. Hydroxychloroquine (HCQ), a well-known anti-malarial drug, is commonly used in clinical practice for its anti-inflammatory actions. However, little is known about its role in renal ischemia/reperfusion (I/R) injury. In the current study, mice were subjected to I/R injury and HCQ was administered for seven days by gavage prior to surgery. In parallel, HK-2 human renal proximal tubule cells were prophylactically treated with HCQ and then were exposed to hypoxia/reoxygenation (H/R). The results showed that HCQ significantly attenuated renal dysfunction evidenced by blunted decreases in serum creatinine and kidney injury molecular-1 expression and the improvement of HK-2 cell viability. Additionally, HCQ markedly reduced macrophage and neutrophil infiltration, pro-inflammatory cytokine production, and NLRP3 inflammasome activation. Mechanistic studies showed that HCQ could inhibit the priming of the NLRP3 inflammasome by down-regulating I/R or H/R-induced NF-κB signaling. Moreover, HCQ reduced cathepsin (CTS) B, CTSD and CTSL activity, and their redistribution from lysosomes to cytoplasm. CTSB and CTSL (not CTSD) were implicated in I/R triggered NLRP3 inflammasome activation. Notably, we found that HCQ attenuated renal injury through downregulation of CTSB and CTSL-mediated NLRP3 inflammasome activation. This study provides new insights into the anti-inflammatory effect of HCQ in the treatment of AKI.

Are Urinary Tubular Injury Markers Useful in Chronic Kidney Disease? A Systematic Review and Meta Analysis

Background

Adverse outcome of chronic kidney disease, such as end stage renal disease, is a significant burden on personal health and healthcare costs. Urinary tubular injury markers, such as NGAL, KIM-1 and NAG, could provide useful prognostic value for the early identification of high-risk patients. However, discrepancies between recent large prospective studies have resulted in controversy regarding the potential clinical value of these markers. Therefore, we conducted the first meta-analysis to provide a more persuasive argument to this debate.

Methods

In the current meta-analysis, based on ten prospective studies involving 29366 participants, we evaluated the role of urinary tubular injury markers (NGAL, KIM-1 and NAG) in predicting clinical outcomes including CKD stage 3, end stage renal disease and mortality. The prognostic values of these biomarkers were estimated using relative risks and 95% confidence interval in adjusted models. All risk estimates were normalized to those of 1 standard deviation increase in log-scale concentrations to minimize heterogeneity. Fixed-effects models were adopted to combine risk estimates. The quality of the research and between-study heterogeneity were evaluated. The level of research evidence was identified according to the GRADE profiler.

Results

uNGAL was identified as an independent risk predictor of ESRD (pooled adjusted relative risk: 1.40[1.21 to 1.61], p<0.001) and of overall mortality (pooled adjusted relative risk: 1.10[1.03 to 1.18], p = 0.001) in patients with chronic kidney disease. A borderline significance of uKIM-1 in predicting CKD stage 3 independently in the community-based population was observed (pooled adjusted relative risk: 1.13[1.00 to 1.27], p = 0.057). Only the prognostic value of uNGAL for ESRD was supported by a grade B level of evidence.

Conclusion

The concentration of uNGAL can be used in practice as an independent predictor of end stage renal disease among patients with chronic kidney disease, but it may be not useful in predicting disease progression to CKD stage 3 among community-based population.

The characteristics and mortality risk factors for acute kidney injury in different age groups in China-a cross sectional study

AIM

Age is an independent risk factor for acute kidney injury (AKI). The causes and outcomes of AKI in children, middle-aged, and older patients are different. The objective of this country-based study was to identify the characteristics and mortality factors for AKI in different age groups in China.

METHODS

Using data from 374,286 adult patients (≥18 years) admitted to 44 study hospitals, we investigated the characteristics and mortality risk factors for AKI in four different age groups: 18-39 years of age, 40-59 years of age, 60-79 years of age, and ≥80 years of age. The identification criteria for AKI included the 2012 KDIGO AKI definition and an expanded criterion.

RESULTS

The country-based survey included 7604 AKI patients (7604/374,286, 2.03%). The proportions of AKI in the four age groups were 11.52%, 30.79%, 41.03%, and 16.66%, respectively. In any age group, the patients with AKI stage 1 were the majority (43.4%, 42.4%, 46.4%, and 52.2%, respectively), and the most common classification of AKI was pre-renal AKI (44.3%, 51.3%, 52.3%, and 56.4%, respectively). The higher AKI peak stage occurred for the in-hospital mortality factors for AKI in all age groups; except for the AKI stage 2 patients in the 18-39 age group.

CONCLUSION

The characteristics and mortality factors for AKI vary by age in China. Elderly patients were the primary population with AKI, and the most common type of AKI was pre-renal AKI. Special caution should be taken to the old population in hospitalized patients to prevent the pre-renal AKI.

Cinacalcet attenuates the renal endothelial-to-mesenchymal transition in rats with adenine-induced renal failure

Elevated serum parathyroid hormone (PTH) is an important complicated phenomenon in patients with chronic kidney disease (CKD). Emerging evidence indicates the involvement of PTH in organ fibrosis, and suppression of PTH by cinacalcet (CINA) ameliorates the progression of fibrotic disorders. However, the underlying mechanisms are largely unknown. The endothelial-to-mesenchymal transition (EndMT) has been shown to be an important mechanism involved in renal fibrosis. The present study aimed to investigate whether CINA treatment attenuated renal EndMT in rats with adenine-induced chronic renal failure (CRF). Compared with the control group, serum PTH was significantly higher in the CRF group and was suppressed after CINA treatment. Serum calcium, phosphorus, and calcium × phosphorus product levels were similar in the CRF group and CINA-treated CRF group. Renal collagen accumulation was significantly increased in the CRF group, which was markedly ameliorated by CINA treatment. Expression of the endothelial marker CD31 was significantly downregulated in rats with CRF, whereas expression of the mesenchymal markers fibroblast specific-protein 1 and α-smooth muscle actin was markedly upregulated. These changes were inhibited by CINA treatment. The protein levels of these EndMT-related markers were strongly correlated with serum PTH concentrations. Furthermore, the in vitro study showed that PTH could significantly increase the expression of fibroblast specific-protein 1 and α-smooth muscle actin and decrease CD31 in mRNA and protein levels in a concentration- and time-dependent manner. In conclusion, our study suggests that reducing serum PTH by CINA treatment could attenuate renal fibrosis via suppression of EndMT in the adenine-induced CRF rat model.

CD2AP mRNA in urinary exosome as biomarker of kidney disease

AIMS

Podocyte injury plays an important role in the pathogenesis of kidney disease. Urinary exosomes are microvesicles released by tubular epithelial cells and podocytes containing information of their originated cells. This study investigated for the first time whether podocyte related mRNA in urinary exosome could serve as novel biomarkers for kidney disease.

METHODS

Urine samples were collected from 32 patients of kidney disease who underwent kidney biopsy and 7 controls. CD2AP, NPHS2 and synaptopodin were detected by real-time RT-PCR on RNA isolated from urinary exosome.

RESULTS

The pellet microvesicles were positively stained with exosome and podocyte marker, AQP2, CD9 and nephrin. CD2AP mRNA was lower (p=0.008) in kidney disease patients compared with controls and decreased with the increasing severity of proteinuria (p=0.06). CD2AP correlated with serum creatinine (r=-0.373, p=0.035), BUN (r=-0.445, p=0.009) and eGFR (r=0.351, p=0.046). Neither NPHS2 nor synaptopodin correlated with parameters of renal function. CD2AP mRNA correlated negatively with 24 hour urine protein (r=-0.403, p=0.022), severity of tubulointerstitial fibrosis (r=-0.394, p=0.026) and glomerulosclerosis (r=-0.389, p=0.031) and could discriminate kidney disease from controls with AUC of 0.821 (p=0.008).

CONCLUSIONS

Urinary exosome mRNA of CD2AP might be a non-invasive tool for detecting both renal function and fibrosis of kidney disease.

FTY720 attenuates tubulointerstitial inflammation and fibrosis in subtotally nephrectomized rats

Tubulointerstitial fibrosis is a common pathway that leads to kidney failure, and persistent tubulointerstitial inflammation is a key event in the development of tubulointerstitial fibrosis. The new immunosuppressive drug FTY720 modifies lymphocyte migration into injured tissues by sequestering lymphocytes within secondary lymphoid organs. However, its therapeutic effect on tubulointerstitial inflammation and fibrosis had not been well understood. This study was designed to explore the effect of FTY720 on tubulointerstitial inflammation and fibrosis in subtotally nephrectomized (SNX) rats. In total, 24 male Sprague-Dawley rats were used. Seven days after 5/6 nephrectomy, rats were randomized to FTY720 (1 mg/kg/d) and placebo-treated groups. Sham-operated rats served as controls. FTY720 significantly attenuated the rise in proteinuria, serum creatinine, urea nitrogen and N-acetyl-β-D-glucosaminidase activity in SNX rats, and reduced the count of peripheral white blood cells and lymphocytes in SNX rats. Morphological analysis revealed that there was severe tubulointerstitial inflammation and fibrosis in SNX group and much more tubulointerstitial infiltrating inflammatory cells with high expression of CD3, CD4, CD8, CD20, CD68, CD163 and CCR-7 in SNX group, as compared with the controls, but the lesions were attenuated significantly by treatment with FTY720. Furthermore, the expressions of proinflammatory molecules (IL-6, TNF-α and MCP-1), profibrotic molecule (TGF-β1) and production of extracellular matrix proteins such as fibronectin and types I and III collagens were upregulated in SNX rats. FTY720 administration significantly reduced these abnormalities. In summary, FTY720 exerts therapeutic effects on tubulointerstitial fibrosis in SNX rats by inhibiting the tubulointerstitial inflammatory response.

Inhibition of TGF-β1/Smad signal pathway is involved in the effect of Cordyceps sinensis against renal fibrosis in 5/6 nephrectomy rats

The present study aimed to investigate the effects of Cordyceps sinensis on renal fibrosis and its possible mechanisms. Sprague-Dawley rats were randomly divided into three groups: sham operation (SHAM) group, 5/6 subtotal nephrectomy (SNx) untreated group, and 5/6 subtotal nephrectomy treated with C. sinensis (2.0 g/kg d) (CS) group. Rats were studied 12 weeks after the surgery, and the CS group presented with significantly lower proteinuria, and better renal function compared with the SNx group (p<0.05). Pathological study showed that the glomerulosclerosis tubulointerstitial injury score was significantly reduced in the CS group compared with the SNx group. Furthermore, the mRNA expression of TGF-β1, Smad2 and Smad3 and the protein expression of TGF-β1, TβRI, TβRII and p-Smad2/3 were attenuated by the C. sinensis treatment. In constrast, the mRNA and protein expression of Smad7 was upregulated. Furthermore, the expression of α-SMA and FSP1 was also significantly attenuated, accompanied by the increasing expression of E-cadherin, suggesting the inhibition of the epithelial-mesenchymal transition (EMT).

IN CONCLUSION

C. sinensis exerted its antifibrotic effect on the SNx rats through the inhibition of the TGF-β1/Smad pathway.

Pirfenidone inhibits macrophage infiltration in 5/6 nephrectomized rats

Tubulointerstitial macrophage infiltration is a hallmark of chronic kidney disease involved in the progression of renal fibrosis. Pirfenidone is a newly identified antifibrotic drug, the potential mechanism of which remains unclear. The aim of this study was to investigate the effects of pirfenidone on M1/M2 macrophage infiltration in nephrectomized rats. Nephrectomized rats were treated with pirfenidone by gavage for 12 wk. Twenty-four hour urinary protein, N-acetyl-β-D-glycosaminidase (NAG) activity, systolic blood pressure, and C-reactive protein were determined. Paraffin-embedded sections were stained for CD68, CCR7, and CD163 macrophages. Monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α), as well as M1 and M2 macrophages secretory markers, were evaluated by real-time RT-PCR and Western blotting analysis. Pirfenidone significantly improved the elevated proteinuria and NAG activity from week 2 onward after surgery. Pirfenidone attenuated interstitial fibrosis and decreased expression of fibrotic markers including transforming growth factor-β(1), connective tissue growth factor, α-smooth muscle actin, fibronectin, and fibroblast-specific protein-1. Pirfenidone significantly decreased the infiltrating macrophages. The number of M1 and M2 macrophages was significantly lower after pirfenidone treatment. MCP-1 and MIP-1α were increased in nephrectomized rats at mRNA and protein levels. Pirfenidone treatment significantly inhibited their expression. The TNF-α, IL-6, and nitric oxide synthases-2 expressed by M1 macrophages were increased in nephrectomized rats, and pirfenidone significantly attenuated their expression. Pirfenidone treatment also significantly decreased arginase-1, dectin-1, CD206, and CD86 expressed by M2 macrophages. Thus pirfenidone inhibits M1 and M2 macrophage infiltration in 5/6 nephrectomized rats, which suggests its efficacy in the early and late periods of renal fibrosis.

A point mutation in the DNA-binding domain of HPV-2 E2 protein increases its DNA-binding capacity and reverses its transcriptional regulatory activity on the viral early promoter

Background

The human papillomavirus (HPV) E2 protein is a multifunctional DNA-binding protein. The transcriptional activity of HPV E2 is mediated by binding to its specific binding sites in the upstream regulatory region of the HPV genomes. Previously we reported a HPV-2 variant from a verrucae vulgaris patient with huge extensive clustered cutaneous, which have five point mutations in its E2 ORF, L118S, S235P, Y287H, S293R and A338V. Under the control of HPV-2 LCR, co-expression of the mutated HPV E2 induced an increased activity on the viral early promoter. In the present study, a series of mammalian expression plasmids encoding E2 proteins with one to five amino acid (aa) substitutions for these mutations were constructed and transfected into HeLa, C33A and SiHa cells.

Results

CAT expression assays indicated that the enhanced promoter activity was due to the co-expressions of the E2 constructs containing A338V mutation within the DNA-binding domain. Western blots analysis demonstrated that the transiently transfected E2 expressing plasmids, regardless of prototype or the A338V mutant, were continuously expressed in the cells. To study the effect of E2 mutations on its DNA-binding activity, a serial of recombinant E2 proteins with various lengths were expressed and purified. Electrophoresis mobility shift assays (EMSA) showed that the binding affinity of E2 protein with A338V mutation to both an artificial probe with two E2 binding sites or HPV-2 and HPV-16 promoter-proximal LCR sequences were significantly stronger than that of the HPV-2 prototype E2. Furthermore, co-expression of the construct containing A338V mutant exhibited increased activities on heterologous HPV-16 early promoter P97 than that of prototype E2.

Conclusions

These results suggest that the mutation from Ala to Val at aa 338 is critical for E2 DNA-binding and its transcriptional regulation.

[Effect of acupoint injection on erythropoietin resistance in patients with chronic renal failure]

OBJECTIVE

To compare the effect on erythropoietin (Epo) resistance between acupoint injection and subcutaneous injection of rHuEpo in patients with chronic renal failure (CRF).

METHODS

Thirty-eight cases were randomly divided into two groups, 19 cases in each one. In subcutaneous injection group (control group), subcutaneous injection of rHuEpo was administered, 3 times a week, lasting 2 months. In acupoint group (observation group), rHuEpo was injected on unilateral Shenshu (BL 23) and Zusanli (ST 36), one point was chosen each time, the bilateral acupoints were injected alternatively, 3 times a week, for 2 months. Meanwhile, a normal control group of 19 healthy persons was set up. The levels of CRP, IL-6, TNF-alpha, Scr, BUN, Hb, Hct and SF were observed.

RESULTS

Before treatment, the values of CRP, IL-6 and TNF-alpha in two groups were all higher than those in normal control group (all P < 0.01). After treatment for 2 months, the values of CRP, IL-6,TNF-alpha, Scr and BUN in two groups decreased apparently and those of Hb, Hct and SF increased obviously, indicating statistic significant differences as compared with the values before treatment separately (P < 0.05, P < 0.01). In comparison between two groups after treatment, every index above in observation group was improved much significantly (P < 0.05, P < 0.01).

CONCLUSION

Acupoint injection of rHuEpo at Zusanli (ST 36) and Shenshu (BL 23) increases significantly the values of Hb, Hct and SF, and decreases apparently the values of BUN, Scr and inflammatory factors, such as CRP, IL-6 and TNF-alpha as compared with subcutaneous injection. Acupoint injection improves Epo resistance and enhances Epo efficacy via alleviating micro-inflammatory state of the body.

[Expression of toll-like receptors on CD14+ monocytes from patients with chronic obstructive pulmonary disease and smokers]

OBJECTIVE

To investigate the expression of toll-like receptor-2 (TLR2), TLR4 on the CD14+ monocytes of patients with stable chronic obstructive pulmonary disease (COPD) and healthy smokers, and to explore the role of TLR2 and TLR4 in COPD pathogenesis.

METHODS

Thirty COPD patients without evidence of acute exacerbation, 21 healthy smokers, and 25 healthy non-smokers underwent measurement of forced expiratory volume in 1 second (FEV(1))% predicted and FEV(1)/forced vital capacity (FVC) by spirometry. The expression of TLR2 and TLR4 surface molecules on human CD14+ monocytes was assessed using fluorescence activated cell sorter analysis by flow cytometry, expressed as relative mean fluorescence intensity (rmfi) and relative positive cell percent (rpcp), and the correlation of TLR expression with lung function parameters was analyzed.

RESULTS

The rmfi and rpcp of TLR2 on CD14+ monocytes of the COPD patients were (6.3 +/- 1.4)% and (52.9 +/- 20.5)% respectively, both significantly lower than those of the healthy smokers [(8.2 +/- 2.2)% and (73.5 +/- 19.0)% respectively] and those of the nonsmokers [(11.0 +/- 2.4)% and (82.8 +/- 17.9)% respectively, all P < 0.01)]. The rmfi of TLR4 of the COPD patients was 2.2 +/- 0.9, significantly lower than that of the nonsmokers (3.0 +/- 0.5, P < 0.01), while similar to that of the healthy smokers (2.5 +/- 0.6, P > 0.05). The rpcp of TLR4 of the COPD patients (M = 1.3%, Q(1) - Q(3): 0.7% - 2.4%) was significantly lower than that of the healthy smokers (M = 4.7%, Q(1) - Q(3): 2.7% - 9.4%, P < 0.01) and nonsmokers (M = 5.3%, Q(1) - Q(3): 2.6% - 8.4%, P < 0.01). The rmfi of TLR2 and TLR4 on CD14+ monocytes of the healthy smokers was lower than that of the nonsmokers (P < 0.05), while the rpcp of TLR2 and TLR4 on CD14+ monocytes of the healthy smokers was similar to that of the nonsmoker (P < 0.05). The expression of TLR2 and TLR4 on monocytes was positively correlated with the lung function parameters, including FEV(1)% predicted and FEV(1)/FVC (all P < 0.01).

CONCLUSIONS

The expression levels of TLR2 and TLR4 on CD14+ monocytes of the stable COPD patients and healthy smokers decreased significantly. The innate immune response may be depressed in the COPD patients and smokers, and the down-regulation of TLR is associated with reduced lung function parameters.

[Influence of passive smoking on the fetus during pregnancy]

The study on the hazard of passive smoking to the fetus during pregnancy was carried out in 188 cases. The rate of SGA, premature labor and neonatal asphyxia in this group were higher than that of 65 cases without passive smoking. The data was analysed by logistic multifactor regression analysis. The result showed that, for those patients with hypertension and husband smoking, the risk of SGA, and neonatal asphyxia were 1.6, 2.8 and 3.2 times higher than those without hypertension and husband smoking. In the group of passive smoking, their blood CoHb and umbilical venous CoHb levels were obviously higher than those of the normal control. The possible cause of hazard of passive smoking to the fetus was also analysed and discussed.