Abrupt Decline in Estimated Glomerular Filtration Rate after Initiating Sodium-Glucose Cotransporter 2 Inhibitors Predicts Clinical Outcomes: A Systematic Review and Meta-Analysis

BACKGRUOUND

The initiation of sodium-glucose cotransporter-2 inhibitors (SGLT2i) typically leads to a reversible initial dip in estimated glomerular filtration rate (eGFR). The implications of this phenomenon on clinical outcomes are not well-defined.

METHODS

We searched MEDLINE, Embase, and Cochrane Library from inception to March 23, 2023 to identify randomized controlled trials and cohort studies comparing kidney and cardiovascular outcomes in patients with and without initial eGFR dip after initiating SGLT2i. Pooled estimates were calculated using random-effect meta-analysis.

RESULTS

We included seven studies in our analysis, which revealed that an initial eGFR dip following the initiation of SGLT2i was associated with less annual eGFR decline (mean difference, 0.64; 95% confidence interval [CI], 0.437 to 0.843) regardless of baseline eGFR. The risk of major adverse kidney events was similar between the non-dipping and dipping groups but reduced in patients with a ≤10% eGFR dip (hazard ratio [HR], 0.915; 95% CI, 0.865 to 0.967). No significant differences were observed in the composite of hospitalized heart failure and cardiovascular death (HR, 0.824; 95% CI, 0.633 to 1.074), hospitalized heart failure (HR, 1.059; 95% CI, 0.574 to 1.952), or all-cause mortality (HR, 0.83; 95% CI, 0.589 to 1.170). The risk of serious adverse events (AEs), discontinuation of SGLT2i due to AEs, kidney-related AEs, and volume depletion were similar between the two groups. Patients with >10% eGFR dip had increased risk of hyperkalemia compared to the non-dipping group.

CONCLUSION

Initial eGFR dip after initiating SGLT2i might be associated with less annual eGFR decline. There were no significant disparities in the risks of adverse cardiovascular outcomes between the dipping and non-dipping groups.

Diagnosis of kidney insufficiency by using the pressure waveforms of wrist-type sphygmomanometers: toward a convenient point-of-care device

OBJECTIVES

Digital sphygmomanometers have been used for more than 40 years in Western medicine for accurately measuring systolic and diastolic blood pressures, which are vital signs observed for the diagnosis of different diseases. Similarly, traditional Chinese medicine (TCM) has been using wrist pulse diagnosis for thousands of years. Some studies have combined digital wrist pulse signals and the diagnosis method of TCM to quantify pulse waves and identify diseases. However, the effectiveness of this approach is limited because of scattered methods and complex pathological features. Moreover, the literature on TCM does not provide quantitative data or objective indicators.

METHODS

In this prospective study, we developed a diagnostic system that contains a modified sphygmomanometer. In addition, we designed a procedure for analyzing pulse waves with 156 features of harmonic modes and a decision tree method for diagnosing kidney insufficiency.

RESULTS

In the decision tree method, at least three features of harmonic modes can achieve an accuracy of 0.86, a specificity of 0.91, and a Cohen's kappa coefficient of 0.72. By comparison, the random forest method can achieve an accuracy of 0.99, a specificity of 0.99, and a Cohen's kappa coefficient of 0.94 within 200 trees. The results of this study indicated that even in patients with kidney insufficiency and complex etiology, common features can be distinguished by identifying changes in pulse waveforms.

CONCLUSION

By using the modified sphygmomanometer to measure blood pressure, people can monitor their health status and take care of it in advance by simply measuring their blood pressure.

Modeling Respiratory Syncytial Virus Adult Vaccination in the United States With a Dynamic Transmission Model

BACKGROUND

Respiratory syncytial virus (RSV) is shown to cause substantial morbidity, hospitalization, and mortality in infants and older adults. Population-level modeling of RSV allows to estimate the full burden of disease and the potential epidemiological impact of novel prophylactics.

METHODS

We modeled the RSV epidemiology in the United States across all ages using a deterministic compartmental transmission model. Population-level symptomatic RSV acute respiratory tract infection (ARI) cases were projected across different natural history scenarios with and without vaccination of adults aged ≥60 years. The impact of vaccine efficacy against ARIs, infectiousness and vaccine coverage on ARI incidence were assessed. The impact on medical attendance, hospitalization, complications, death, and other outcomes was also derived.

RESULTS

Without a vaccine, we project 17.5-22.6 million symptomatic RSV ARI cases annually in adults aged ≥18 years in the US, with 3.6-4.8 million/year occurring in adults aged ≥60 years. Modeling indicates that up to 2.0 million symptomatic RSV-ARI cases could be prevented annually in ≥60-year-olds with a hypothetical vaccine (70% vaccine efficacy against symptomatic ARI and 60% vaccine coverage) and that up to 0.69 million/year could be prevented in the nonvaccinated population, assuming 50% vaccine impact on infectiousness.

CONCLUSIONS

The model provides estimated burden of RSV in the US across all age groups, with substantial burden projected specifically in older adults. Vaccination of adults aged ≥60 years could significantly reduce the burden of disease in this population, with additional indirect effect in adults aged <60 years due to reduced transmissibility.

Comparison of Humoral Antibody Responses and Seroconversion Rates between Two Homologous ChAdOx1 nCoV-19 and mRNA-1273 Vaccination in Patients Undergoing Maintenance Hemodialysis

BACKGROUND

Hemodialysis patients are at an increased risk of SARS-CoV-2 infection and are excluded from preauthorization COVID-19 vaccine trials; therefore, their immunogenicity is uncertain.

METHODS

To compare the antibody responses to homologous ChAdOx1 and mRNA-1273 SARS-CoV-2 vaccination in hemodialysis patients, 103 age- and sex-matched hemodialysis patients with two homologous prime-boost vaccinations were recruited to detect anti-receptor-binding domain (RBD) IgG levels and seroconversion rates (SCRs) 14 days after a prime dose (PD14), before and 28 days after a boost dose (pre-BD0 and BD28).

RESULTS

Both mRNA-1273 and ChAdOx1 vaccinations elicited immunogenicity in study subjects, and the former induced higher anti-RBD IgG levels than the latter. The SCRs of both groups increased over time and varied widely from 1.82% to 97.92%, and were significantly different at PD14 and pre-BD0 regardless of different thresholds. At BD28, the SCRs of the ChAdOx1 group and the mRNA-1273 group were comparable using a threshold ≥ 7.1 BAU/mL (93.96% vs. 97.92%) and a threshold ≥ 17 BAU/mL (92.73% vs. 97.92%), respectively, but they were significantly different using a threshold ≥ 20.2% of convalescent serum anti-RBD levels (52.73% vs. 95.83%). The seroconversion (≥20.2% of convalescent level) at BD28 was associated with mRNA-1273 vaccination after being adjusted for age, sex, body mass index, and the presence of solicited reactogenicity after a prime vaccination.

CONCLUSION

Our prospective, observational cohort indicates that a full prime-boost mRNA-1273 vaccination is likely to provide higher immune protection in hemodialysis patients compared to ChAdOx1, and this population with a prime-boost ChAdOx1 vaccination should be prioritized for a third dose.

Exploring the Relevance between Gut Microbiota-Metabolites Profile and Chronic Kidney Disease with Distinct Pathogenic Factor

The intimate correlation of chronic kidney disease (CKD) with structural alteration in gut microbiota or metabolite profile has been documented in a growing body of studies. Nevertheless, a paucity of demonstrated knowledge regarding the impact and underlying mechanism of gut microbiota or metabolite on occurrence or progression of CKD is unclarified thus far. In this study, a liquid chromatography coupled-mass spectrometry and long-read sequencing were applied to identify gut metabolites and microbiome with statistically-discriminative abundance in diabetic CKD patients (n = 39), hypertensive CKD patients (n = 26), or CKD patients without comorbidity (n = 40) compared to those of healthy participants (n = 60). The association between CKD-related species and metabolite was evaluated by using zero-inflated negative binomial (ZINB) regression. The predictive utility of identified operational taxonomic units (OTUs), metabolite, or species-metabolite association toward the diagnosis of incident chronic kidney disease with distinct pathogenic factor was assessed using the random forest regression model and the receiver operating characteristic (ROC) curve. The results of statistical analyses indicated alterations in the relative abundances of 26 OTUs and 41 metabolites that were specifically relevant to each CKD-patient group. The random forest regression model with only species, metabolites, or its association differentially distinguished the hypertensive, diabetic CKD patients, or enrolled CKD patients without comorbidity from the healthy participants. IMPORTANCE Gut dysbiosis-altered metabolite association exhibits specific and convincing utility to differentiate CKD associated with distinct pathogenic factor. These results present the validity of pathogenesis-associated markers across healthy participants and high-risk population toward the early screening, prevention, diagnosis, or personalized treatment of CKD.

Single-centre cross-sectional study on the impact of cumulative erythropoietin on bone mineral density in maintenance dialysis patients

OBJECTIVES

Numerous factors are associated with the risk of osteoporosis in patients with chronic kidney disease, including vitamin D deficiency, hypocalcaemia, hyperphosphataemia and secondary hyperparathyroidism. This study aimed to assess the correlation between cumulative erythropoietin (EPO) doses and osteoporosis risk in patients on chronic dialysis. A further objective was to determine the bone mineral density (BMD) of patients undergoing dialysis and its correlation with specific clinical and biochemical factors.

SETTING

The study was undertaken at a tertiary care centre within the southern region of the Taipei Metropolitan area.

PARTICIPANTS

This cross-sectional study included 165 participants aged 41-90 years. Dual-energy X-ray absorptiometry was used to measure BMD. A total of 108 age-matched and sex-matched participants were selected for further analysis. Stepwise multiple regression analysis was used to investigate the relationship between bone measurements and bone diseases' risk factors.

PRIMARY AND SECONDARY OUTCOMES

The primary outcome of this study was to assess the T-scores of the participants who received dialysis for more than 3 months in our institution. The secondary outcome was using a receiver operating curve to predict osteoporosis development in patients on dialysis who received EPO treatments.

RESULTS

The mean age of the participants was 66.6±11.1 years. A total of 99 (60%) participants (41 men, 58 women) were diagnosed as having osteoporosis. Fifty-four (32.7%) participants with T-scores >-2.5 but <-1.0 were diagnosed as having osteopenia. Osteoporotic participants received 1.61±1.52 million units EPO compared with nonosteoporotic participants, who received 1.01±0.64 million units (EPO1 model), p=0.015. The cumulative EPO dose negatively correlated with the T-scores of participants (p<0.0001).

CONCLUSION

On the basis of the results of the study, cumulative EPO doses show a negative correlation with BMD development in patients on chronic dialysis.

Inverse Relationship between Mean Corpuscular Volume and T-Score in Chronic Dialysis Patients

Background and Objectives: Osteoporosis and anemia are prevalent among chronic kidney disease stage 5D (CKD stage 5D) patients. Osteoblasts are known as the niche cells of hematopoietic stem cells (HSCs) and stimulate HSCs to form blood-cell lineages within bone marrow microenvironments. We hypothesized that an inverse correlation may exist between mean corpuscular volume (MCV), a surrogate for ineffective hematopoiesis, and bone mineral density (BMD) in the CKD stage 5D population. Materials and Methods: This is a cross-sectional designed cohort study evaluating CKD stage 5D patients who have received dialysis therapy for over three months. Baseline clinical characteristics and laboratory data were prospectively collected. The dual-energy X-ray absorptiometry (DXA) method was used to measure BMD at five sites, which were bilateral femoral neck, total hip, and lumbar spine 1–4. The Pearson correlation test was initially adopted, and a multivariate linear regression model was further applied for potential confounder adjustments. Results: From September 2020 to January 2021, a total of 123 CKD stage 5D patients were enrolled. The Pearson correlation test revealed a significant inverse association between MCV and BMD at bilateral femoral neck and lumbar spine. The lowest T-score of the five body sites was determined as the recorded T-score. After adjustments for several potential confounding factors, the multivariate linear regression model found consistent negative associations between T-score and MCV. Conclusions: The present study found significant inverse correlations between MCV and BMD at specific body locations in patients on dialysis. A decreased T-score was also found to be associated with macrocytosis after adjustments for confounding variables. However, direct evidence for the causative etiology was lacking.

Does ultrasound education improve anatomy learning? Effects of the Parallel Ultrasound Hands-on (PUSH) undergraduate medicine course

BACKGROUND

As ultrasound has become increasingly prominent in medicine, portable ultrasound is perceived as the visual stethoscope of the twenty-first century. Many studies have shown that exposing preclinical students to ultrasound training can increase their motivation and ultrasound competency. However, few studies have discussed the effect of ultrasound training on anatomy learning.

METHOD

The Parallel Ultrasound Hands-on (PUSH) course was designed to investigate whether or not ultrasonography training affects anatomy knowledge acquisition. The PUSH course included anatomical structures located in the chest and abdomen (target anatomy) and was conducted in parallel to the compulsory gross anatomy course. Learners (n = 140) voluntarily participated in this elective course (learners in the course before the midterm examination (Group 1, n = 69), or after the midterm examination (Group 2, n = 71)). Anatomy examination scores (written and laboratory tests) were utilized to compare the effects of the PUSH course.

RESULT

Group 1 obtained significantly higher written test scores on the midterm examination (mean difference [MD] = 1.5(7.6%), P = 0.014, Cohen's d = 0.43). There was no significant difference in the final examination scores between the two groups (Written Test: MD = 0.3(1.6%), P = 0.472). In Laboratory test, both mid-term (MD:0.7(2.8%), P = 0.308) and final examination (MD:0.3(1.5%), P = 0.592) showed no significant difference between two groups. Students provided positive feedback in overall learning self-efficacy after the PUSH course (Mean = 3.68, SD = ±0.56 on a 5-point Likert scale). Learning self-efficacy in the cognitive domain was significantly higher than that in the affective domain (MD = 0.58; P < 0.001) and psychomotor domain (MD = 0.12; P = 0.011).

CONCLUSION

The PUSH course featured a hands-on learning design that empowered medical students to improve their anatomy learning.

A Consistency Model for Identifying the Effects of n-3 and n-6 Fatty Acids on Lipoproteins in Dialysis Patients

Numerous randomized controlled trials (RCTs) and meta-analyses have assessed the effects of supplemental dietary polyunsaturated fatty acids (PUFAs) on levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) and the LDL/HDL ratio in patients receiving renal replacement therapy (RRT). However, results are ambiguous due to mixed reports of various nutrients used in the intervention group. We performed a network meta-analysis of RCTs to assess the effects of PUFAs on lipid profiles in patients undergoing RRT. RCTs performed before November 2021 were gathered from three databases. The means, standard deviations and the number of cases for each arm were independently extracted by two authors to form a network meta-analysis of LDL and HDL levels and the LDL/HDL ratio in a random effects model. Twenty-eight RCTs (n = 2017 subjects) were included in this study. The pooled results revealed that the combination of omega-3 fatty acids (n-3) and omega-6 fatty acids (n-6) produced significantly lower LDL (standardized mean difference (SMD) = −1.43, 95% confidence interval: −2.28 to −0.57) than the placebo. Both n-3 fatty acids (SMD = 0.78) and the combination of n-3 + n-6 (SMD = 1.09) benefited HDL significantly compared with placebo. Moreover, n-3 alone also exhibited a significantly lower LDL/HDL ratio than placebo. Collectively, PUFAs seem to be adequate nutrients for controlling lipoproteins in patients undergoing RRT. Specifically, n-3 + n-6 supplementation improved LDL levels, while n-3 improved HDL levels and the LDL/HDL ratio. However, our data provide limited information on specific dosages of PUFAs to form a concrete recommendation.

Effect of profit status in facilities on the mortality of patients on long-term haemodialysis: a nationwide cohort study

OBJECTIVES

Over the past two decades, debates on whether the profit status of dialysis facilities influences patient prognosis have been popular in the USA. Taiwan is one of the regions with the highest rate per capita of kidney replacement therapy worldwide, but no similar research has been conducted to date. This is the first study to address this issue.

DESIGN

This was a nationwide retrospective cohort study based on the Taiwan Renal Registry Data System.

SETTING

Patients were categorised into two groups based on the profit status (for-profit, not-for-profit (NFP)) of dialysis facilities, with 31 350 patients in each group. The patients were followed up from 2005 to 2012.

PARTICIPANTS

Patients with uraemia who underwent long-term haemodialysis in private dialysis facilities and public facilities were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

Survival analyses were performed to compare prognosis between the two groups. Adjustments to patients' basic profile, and facilities' geographical distribution, level, and length of ownership were carried out to minimise possible confounding effects.

RESULTS

Analysis revealed that NFP dialysis facilities had better outcomes (HR=0.91, 95% CI (0.89 to 0.93)). A favourable effect remains with the adjustment of the facilities' level, geographical distribution (HR=0.89, 95% CI (0.86 to 0.93)) or length of ownership (HR=0.95, 95% CI (0.89 to 0.95)). Survival analysis based on the geographical distribution and level of facilities was also conducted, which showed better prognosis in medical centres in the six municipalities, whereas worse prognosis was found in local hospitals not located in these municipalities.

CONCLUSION

Our findings suggest that in contemporary settings in Taiwan, treatment at NFP dialysis facilities was associated with a better prognosis. The results should be interpreted with caution since the possibility of residual confounding effects and uncertainty of casual relations exist due to the nature of observational studies.

Why do pre-clinical medical students learn ultrasound? Exploring learning motivation through ERG theory

BACKGROUND

In recent years, point-of-care ultrasound (POCUS) has become an essential field of medical education. Bedside ultrasound has become a necessary skill for clinical physicians. Previous studies have already discussed the importance of advancements in ultrasound education. However, learning motivations for ultrasound education have seldom been analyzed in the literature. For medical students, learning ultrasound could have a relevance for their future career. The Existence, Relatedness and Growth (ERG) theory extended Maslow's hierarchy of needs through these three concepts. This theory has been widely used in the workplace to analyze employee job performance but has not yet been applied in medical education. In this study ERG theory was applied to analyze pre-clinical medical students' learning motivation toward ultrasound education.

METHOD

This mixed method study used online questionnaires consisting of open-ended questions as a data collection tool, and based on these results, both qualitative and quantitative analysis were conducted. Participants answered a series of neutral and open-ended questions regarding their motivations to learn ultrasonography. After data collection, a three-step analysis was conducted based on the grounded theory approach. Finally, the results of the thematic coding were used to complete additional quantitative analysis.

RESULTS

The study involved 140 pre-clinical medical students, and their responses fell into 13 specific categories. The analysis demonstrated that students' motivations toward ultrasound education were unbalanced across the three ERG domains (F = 41.257, p < .001). Pairwise comparisons showed that students mentioned existence motivation (MD = 39.3%; p < .001) and growth motivation (MD = 40.7%; p < .001) more frequently than relatedness motivation. However, there was no significant difference between existence motivation and growth motivation (MD = - 1.4%; p = .830).

CONCLUSION

The results revealed that students placed a high value on existence and growth needs rather than relatedness based on the survey. In addition, the findings suggest that ERG theory can be a useful tool to conduct medical education motivation analysis.

Combined protective effects of oligo-fucoidan, fucoxanthin, and L-carnitine on the kidneys of chronic kidney disease mice

Chronic kidney disease (CKD) is a common global progressive disease, but there are no ideal drugs for the treatment. Fucoidan and fucoxanthin, and L-carnitine are one of the very few natural products that have a therapeutic effect on CKD in animal experiments. However, the combined effects of these compounds on CKD are unknown. We established a mouse CKD model by right nephrectomy with transient ischemic injury to the left kidney. Oligo-fucoidan and fucoidan were extracted from Laminaria japonica. We fed CKD mice with the two compounds and L-carnitine to evaluate the combined effects on CKD. Oligo-fucoidan and fucoidan inhibited renal fibrosis and reduced serum creatine in CKD mice to a greater extent than any single compound. L-carnitine had no measurable effect on renal fibrosis but promoted the protective effect of the mixture of oligo-fucoidan and fucoidan on renal function in CKD mice. In the two-month safety test, the combined mixture further improved renal function and did not elevate serum aspartate aminotransferase and alanine aminotransferase levels in CKD mice. Furthermore, the weights of CKD mice treated with the combination increased to the normal level. We also found that all oligo-fucoidan, fucoxanthin, and L-carnitine inhibit H2O2-induced apoptosis and activated Akt in rat renal tubular cells. Our results confirm that oligo-fucoidan, fucoxanthin, and L-carnitine have a combined protective effect on the kidneys. The combined mixture may be beneficial for CKD patients.

Impact of virtual reality anatomy training on ultrasound competency development: A randomized controlled trial

PURPOSE

The use of Virtual Reality (VR) in health professions education has increased dramatically in recent years, yet there is limited evidence of its impact on educational outcomes. The purpose of the study was to assess the impact of VR anatomy instruction on the ultrasound competency of novice learners participating in a ultrasonography workshop.

METHOD

We designed a VR-enhanced ultrasonography training program and utilized a plane transection tool to interact with a three-dimensional (3D) VR model of the human body which facilitated the 3D conceptualization of the spatial relationship of anatomical structures, leading to faster and better development of ultrasonographic competency. This was a randomized control study which enrolled third-year medical students (n = 101) without previous exposure to formal or informal ultrasonography training. The participants were randomly divided into an intervention and control group. We assessed participants' competency through ultrasound performance stations on live subjects, we also measured anatomical and ultrasound image identification ability using multiple choice tests.

RESULT

Participants in the intervention group (median = 16; interquartile 13 to 19) had significantly higher scores in ultrasonography task performance tests than the control group (median = 10; interquartile 7 to 14; Mann-Whitney U = 595; P < 0.01). In sub-group analysis, the intervention group performed significantly better in the six out of ten ultrasound tasks. Participants in the intervention group also had greater improvement in ultrasonographic image identification MCQ tests than the control group (Mann-Whitney U = 914; P < 0.05).

CONCLUSION

This study suggests that VR-enhanced anatomical training could be of significant benefit in ultrasonography training by promoting a better understanding of the spatial relationships of anatomical structures and the development of early psychomotor skills transferable to the handling of ultrasonographic probes.

1173Anti-heart and anti-intercalated disk autoantibodies: possible novel biomarkers of cardiac sarcoidosis

Background

Sarcoidosis is an immune-mediated disease; cardiac involvement, a granulomatous form of myocarditis, is under-recognised and prognostically relevant, as it can present with significant morbidity and mortality. Anti-heart autoantibodies (AHA) and anti-intercalated disk autoantibodies (AIDA) are reliable autoimmune markers in non-sarcoidosis myocarditis forms.

Purpose

The aim of this study was to assess the potential role of serum AHA and AIDA in cardiac sarcoidosis.

Methods

This is a cross-sectional study on a series of 29 patients with biopsy proven extra-cardiac sarcoidosis and with biopsy-proven or clinically suspected cardiac involvement, who were tested for AHA and AIDA. Patients were recruited in two recruiting tertiary centres, in USA and Italy. AHA and AIDA were detected by indirect immunofluorescence on human myocardium and skeletal muscle. Controls included sera from patients with non-inflammatory cardiac disease (NICD) (n=160), with ischemic heart failure (IHF) (n=141) and normal blood donors (NBD) (n=270).

Results

The frequencies of AHA and of AIDA were higher in sarcoidosis (86%; 62%) than in NICD (8%; 4%), IHF (7%; 2%), NBD (9%; 0%) (p=0.0001; p=0.0001 respectively). Sensitivity and specificity were: 86% and 92% for positive AHA and 62% and 98% for positive AIDA, respectively (see figure).

Figure 1

Conclusions

The detection of serum AHA and AIDA in biopsy-proven or clinically suspected cardiac sarcoidosis supports the involvement of heart-specific autoimmunity in the majority of our cases and may provide a novel non invasive diagnostic marker.

P5563Biopsy proven myocarditis: clinical and instrumental predictors of adverse prognosis at presentation

Background

Myocarditis is an insidious and potentially fatal illness with different clinical presentations and an unpredictable course. Prompt recognition of high risk patients is of paramount importance in preventing major adverse events.

Purpose

To identify predictors of dismal prognosis in a large cohort of patients with biopsy proven myocarditis.

Methods

Univariate analysis was used to identify predictors of death and heart transplant in a prospective cohort of 366 patients with biopsy proven myocarditis (aged 38±17, male 66%) using student's test and contingency tables as appropriate.

Results

At the time of follow up 46 patients (13%) were dead or received heart transplant (DHTX), 283 (77%) were alive (A) and 37 (10%) lost at follow up. Age at presentation was 33±20 y in DHTX v.s 39±15 in A cohort (p=0.057). Clinical features predicting adverse prognosis included female gender (p=0.002), heart failure at presentation (p=0.000), NYHA class II to IV (p=0.000). Clinical and radiographic signs of both left and right heart failure suggested worse outcome (p=0.000) as well as ongoing anticoagulation therapy (p=0.009). On ECG right (R) or left (L) axis deviation was a strong predictor of events (p=0.000). From an echocardiography perspective the presence of mild to severe mitral regurgitation (p=0.03), reduced left ventricular systolic function (FE) (p=0.000), reduced right ventricular fractional area change (FAC) (p=0.035) was strongly correlated to death or heart transplant. On cardiac catheterization the variables predicting unfavourable outcome included reduced left ventricular systolic pressure (LVSP) (p=0.000), reduced mean aortic pressure (mAP) (p=0.002), increased mean right atrial pressure (RAP) (p=0.001), FE on angiography (p=0.000). On cardiac biopsy (Bx) negative predictors were giant cell histology type (p=0.000) and PCR positive for viral genome (p=0.02) particularly for parvovirus B19 (p=0.04), adenovirus (p=0.04), and Epstein Barr virus (EBV) (p=0.03). See Tab 1

Table 1

Conclusion

Female gender, HF like presentation, reduced LV and RV systolic function, R or L axis deviation on ECG, presence of viral PCR or giant cell histology on Bx, reduced LVSP and mAP; increased RAP may be useful parameters to identify high risk patients on presentation. This may increase clinical efforts and surveillance in this subgroup in order to reduce the incidence of major adverse events.

P4651Biopsy-proven myocarditis: independent predictors of dismal prognosis, relapse and role of immunosuppressive therapy

Background

Biopsy-proven myocarditis may be infectious or autoimmune. Risk stratification in biopsy-proven myocarditis and the role of immunosuppressive therapy in autoimmune forms have not been completely defined.

Purpose

To identify clinical, instrumental and immunological predictors of death, cardiac transplantation and relapse in a prospective cohort of 314 biopsy-proven myocarditis patients, and describe the effect of immunosuppressive treatment on secondary outcome measures, e.g. left ventricular ejection fraction (LVEF), in a subgroup of 45 consecutive patients with biopsy-proven autoimmune myocarditis diagnosed in our Cardiology Clinic.

Methods

Univariate and multivariate Cox regression analysis were used to identify predictors of death, heart transplant, and relapse in a cohort of 314 patients with biopsy-proven myocarditis (male 75%, median age 37). Actuarial survival free from death or transplant was calculated by the Kaplan-Meier method.

Results

Actuarial survival free from death or heart transplantation was 83% at 5 years. Among the clinical, instrumental and immunological features at diagnosis, independent predictors of death or heart transplantation by multivariable analysis were a lower transthoracic echocardiographic biplane LVEF% (p=0.001) and high serum titre for anti-nucler (ANA) and anti-cardiac endothelial cell autoantibodies (AECA). The only independent predictor of relapse was previous history of myocarditis. Immunosuppressive therapy was associated with a significantly favorable effect on LVEF (LVEF pre-therapy 37% (26; 50 interquartile range) vs. LVEF post-therapy 59% (48; 65 interquartile range), respectively, p=0.000).

Conclusions

In biopsy-proven myocarditis left ventricular dysfunction at diagnosis and autoimmune pathogenesis are associated with dismal prognosis, immunosuppressive therapy with improved LVEF in autoimmune patients.

Magnetic anisotropy manipulation of the femtosecond laser-excited spin wave modes in full-Heusler Co2Fe1-x Mn x Al films

Spin-wave dynamics in full-Heusler Co₂Fe_1-x Mn _x Al films have been investigated using all-optical pump-probe magneto-optical polar Kerr spectroscopy. We find magnetic damping and anisotropy can be modulated by composition x. Damon-Eshbach (DE) spin wave occurs only in the samples which present intrinsic magnetic damping and have huge uniaxial magnetic anisotropy, implying that intrinsic magnetic damping and huge uniaxial magnetic anisotropy is the necessary conditions to excite coherent DE spin wave. Kittel spin wave appears in low uniaxial magnetic anisotropic samples and presents extrinsic magnetic damping. Therefore, laser-excited spin-wave modes can be manipulated by magnetic anisotropy, whose physical picture is discussed phenomenologically.

Double filtration plasmapheresis in treatment of acute pancreatitis associated with severe hypertriglyceridemia: Three case reports

RATIONALE

Severe hypertriglyceridemia is the 3rd-leading cause of acute pancreatitis. Current treatment option for hypertriglyceridemia associated with acute pancreatitis is mainly supportive measures, including adequate fluid supply, pain management, and broad-spectrum antibiotics if necessary. Extracorporeal method by mean of plasmapheresis is effective in reducing serum level of triglyceride. It has been proposed to have therapeutic potential in limited small sample studies.

PATIENT CONCERNS

A retrospective review of therapeutic effect of double filtration plasmapheresis in treating hypertriglyceridemia associated with acute pancreatitis was conducted by enlisting 3 patients who meet the criteria for the present study.

DIAGNOSES

Three patients met the criteria for hypertriglyceridemia (serum level >800 mg/dL) associated with acute pancreatitis (either with elevated serum level of lipase and/or amylase and/or with computed tomography evidence of acute pancreatitis).

INTERVENTIONS

Patients received double filtration plasmapheresis.

OUTCOMES

We found that an effective reduction of triglyceride was achieved on an average of 84.7% as a result of a single session of plasmapheresis. All 3 of our patients survived, but needed extended hospitalization.

LESSONS

A substantial clinical trial is required to further assess the effectiveness of plasmapheresis in managing of acute pancreatitis in the setting of hypertriglyceridemia.

Alleviative effect of fucoxanthin-containing extract from brown seaweed Laminaria japonica on renal tubular cell apoptosis through upregulating Na+/H+ exchanger NHE1 in chronic kidney disease mice

ETHNOPHARMACOLOGICAL RELEVANCE

Brown seaweed is a common food for Asians, and the bioactive ingredient fucoxanthin exerts anti-apoptotic activities in several cell types. Renal tubular cell apoptosis is one of the common cellular events leading to renal fibrosis and chronic kidney disease (CKD). However, the influence of fucoxanthin-containing brown seaweed extract on CKD is still unknown. We intended to evaluate the inhibitory effect of fucoxanthin-containing extract from brown seaweed on renal apoptosis under CKD condition and its molecular mechanism.

MATERIALS AND METHODS

The fucoxanthin-containing brown seaweed extract (LJE) was prepared from Laminaria japonica. We investigated how LJE influences on both doxorubicin-treated rat renal tubular cells (NRK-52E) and the renal symptoms of nephrectomy-induced CKD mice.

RESULTS

LJE inhibited doxorubicin-induced apoptosis and upregulated Na+/H+ exchanger isoform 1 (NHE1) expression in NRK-52E cells, which were blocked by the NHE1 inhibitor cariporide. LJE also upregulated peroxisome proliferator-activated receptor alpha (PPARα). PPARα siRNA transfection inhibited LJE-induced NHE1 expression and anti-apoptotic effect. In CKD mice, LJE increased NHE1 expression in renal tubules and reduced apoptotic renal tubular cells, but not in PPARα knockout mice. The inhibitory effect of LJE on apoptosis also reduced renal tubulointerstitial fibrosis and improved renal function in CKD mice.

CONCLUSION

We demonstrated that LJE inhibits renal apoptosis via NHE1 upregulation. The anti-apoptotic effect of LJE also improves renal function in CKD mice. Therefore, fucoxanthin-containing brown seaweed may have a therapeutic potential for CKD patients.

Plasmon-activated water effectively relieves hepatic oxidative damage resulting from chronic sleep deprivation

The role of the hepato-protective agent plasmon-activated water (PAW) as an innovative anti-oxidant during chronic sleep deprivation (SD) is realized in this study. PAW possesses reduced hydrogen-bonded structure, higher chemical potential and significant anti-oxidative properties. In vitro tests using rat liver cell line (Clone-9) have demonstrated that PAW is non-cytotoxic and does not change the cellular migration capacity. The in vivo experiment on SD rats suffering from intense oxidative damage to the liver, an extremely common phenomenon in the present-time with deleterious effects on metabolic function, is performed by feeding PAW to replace deionized (DI) water. Experimental results indicate that PAW markedly reduces oxidative stress with enhanced bioenergetics in hepatocytes. PAW also effectively restores hepatocytic trans-membrane ion homeostasis, preserves membranous structures, and successfully improves liver function and metabolic activity. In addition, the hepato-protective effects of PAW are evidently demonstrated by the reduced values of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) and the recovery of total protein and albumin levels. With clear evidences of PAW for protecting liver from SD-induced injury, delivering PAW as a powerful hepato-protective agent should be worthy of trailblazing new clinical trials in a healthier, more natural, and more convenient way.

Autophagy inhibition increased the anti-tumor effect of cisplatin on drug-resistant esophageal cancer cells

The sensitivity of tumor cells to treatment can be affected by autophagy. The drug resistance of esophageal cancer cells against cisplatin occurs during the long period of chemotherapy drug treatment. This study was designed to observe the effect autophagy has on the occurrence of esophageal cancer cell drug resistance against cisplatin and investigate its molecular mechanism in order to provide new details and strategies for the clinical treatment of esophageal cancer, especially cisplatin treatment. The detection methods used in this study were 3-(4,5-dimethylthiazd-2-yl)-2,5-dipheny-ltetrazolium bromide (MTT) colorimetric assay, clone survival technique, small interfering RNA (siRNA) transfection, and Western blot. Autophagy is a protection mechanism of drug-resistant cells processed by cisplatin, and maintains the cell clone survival ability. Autophagy activation requires the involvement of Atg5 and Atg7.

Emerging Role for Mammalian Target of Rapamycin in Male Fertility

Male fertility is modulated by environmental, endocrine, paracrine, and metabolic cues. Mammalian target of rapamycin (mTOR) coordinates many cellular events in response to those signals. Here, we discuss how the mTOR pathway integrates and mediates signals throughout the male reproductive system, acting as a central player in the control of spermatogenesis.

Multifunctions of Excited Gold Nanoparticles Decorated Artificial Kidney with Efficient Hemodialysis and Therapeutic Potential

Chronic kidney disease (CKD) is inflammation-related. Patients with chronic renal failure who undergo hemodialysis (HD) have some acute adverse effects caused by dialysis-induced oxidative stress, protein adsorption, platelet adhesion, and activation of coagulation and inflammation. Here, resonantly illuminated gold nanoparticles-modified artificial kidney (AuNPs@AK) for achieving high efficiency accompanying therapeutic strategy for CKD during HD is proposed. The efficiency in removing uremic toxins increased obviously, especially in the presence of protein (closer to the real blood). The excited AuNPs@AK expressed negatively charged surface reduced some acute adverse effects caused by dialysis-induced protein adsorption, platelet adhesion, and activation of coagulation, thus avoiding thrombosis during HD. Unlike to traditional HD which provides only one function of removing uremic toxins, the solution collected from the outlet of the sample channel of excited AuNPs@AK showed an efficient free radical scavenger that could decrease dialysis-induced oxidative stress. In the CKD mouse model, this antioxidative solution from excited AuNPs@AK further decreased fibronectin expression and attenuated renal fibrosis, suggesting a reduced inflammatory response. These successful in vitro and in vivo approaches suggest that resonantly illuminated AuNPs@AK in HD take multiadvantages in shortening treatment time and reducing risk of adverse effects, which promise trailblazing therapeutic strategies for CKD.

Effects of low amplitude pulsed radiofrequency stimulation with different waveform in rats for neuropathic pain

Pulsed-radiofrequency (PRF) electrical stimulation has been widely used for chronic pain treatment. It has been demonstrated with advantages of low temperature over traditional continuous radiofrequency (CRF) lesions with higher amplitude and mono polar electrode to treat pain in clinics (frequency 500 KHz, Pulse duration 20 msec, Amplitude 45 V, Treatment 2 min). We compare the effects of different pulse waveforms and PRF parameters (Pulse duration 25 ms, Treatment duration 5 min, low amplitude of 2.5/1.25 V) with a miniature bi-polar electrode on Dorsal root ganglion (DRG). The pain relief effect due to PRF is evaluated by using Von Frey method for the pain threshold index based on behavior response to mechanical stimulus of various strengths. Experimental results of Von Frey Score show that the sinusoidal group has higher responses than the square wave one. Both fast and secondary expressed proteins of c-fos and pp38 are measured from spinal cord tissue sectioning slides to characterize the pain associated inflammatory responses and their responses due to PRF stimulation.

MicroRNA-328 inhibits renal tubular cell epithelial-to-mesenchymal transition by targeting the CD44 in pressure-induced renal fibrosis

Epithelial-mesenchymal transition (EMT) occurs in stressed tubular epithelial cells, contributing to renal fibrosis. Initial mechanisms promoting EMT are unknown. Pressure force is an important mechanism contributing to the induction and progression of renal fibrogenesis in ureteric obstruction. In our study of cultured rat renal tubular cells (NRK-52E) under 60 mmHg of pressure, we found that the epithelial marker E-cadherin decreased and mesenchymal markers, e.g., α-smooth muscle actin, fibronectin and Snail, increased. Pressure also induced the expression of connective tissue growth factor and transforming growth factor-β. MicroRNA array assays showed that pressure reduced miR-328 at the initial stage of pressurization. We identified a potential target sequence of miR-328 in rat CD44 3′-untranslated regions. In contrast with the miR-328 expression, CD44 expression was up-regulated at the initial pressurization stage. We also found that miR-328 expression decreased and CD44 increased in ureteric obstruction kidneys in the animal study. CD44 siRNA transfection significantly increased E-cadherin expression and inhibited pressure-induced EMT. Both hyaluronan binding peptide pep-1 and osteopontin neutralizing antibody inhibited pressure-induced EMT. Our results suggest that miR-328-mediated CD44 transient upregulation is an important trigger of the pressure-induced EMT in renal fibrosis.

High-volume plasma exchange in a patient with acute liver failure due to non-exertional heat stroke in a sauna

Heat stroke is a life-threatening condition characterized by an increased core body temperature (over 40°C) and a systemic inflammatory response, which may lead to a syndrome of multiple organ dysfunction. Heat stroke may be due to either strenuous exercise or non-exercise-induced exposure to a high environmental temperature. Current management of heat stroke is mostly supportive, with an emphasis on cooling the core body temperature and preventing the development of multiple organ dysfunction. Prognosis of heat stroke depends on the severity of organ involvement. Here, we report a rare case of non-exercise-induced heat stroke in a 73-year-old male patient who was suffering from acute liver failure after prolonged exposure in a hot sauna room. We successfully managed this patient by administering high-volume plasma exchange, and the patient recovered completely after treatment.

Urotensin II exerts antiapoptotic effect on NRK-52E cells through prostacyclin-mediated peroxisome proliferator-activated receptor alpha and Akt activation

Urotensin II (UII) is a cyclic vasoactive peptide which is mainly expressed in kidneys. Although elevated plasma UII levels are associated with renal impairment, the influence of UII on renal injury is unclear. In this study, we monitored the influence of UII on gentamicin-induced apoptosis in rat tubular cells (NRK-52E). We found that UII significantly reduced gentamicin-induced apoptosis and apoptotic signals. Blocking endogenous UII secretion caused cells to be more susceptible to gentamicin. In gentamicin-treated mice, UII also expressed protective effect on renal tubular cells. UII was also found to induce prostacyclin (PGI2) production, which caused peroxisomal proliferator-activated receptor α (PPARα) activation as revealed by both PGI2 synthase siRNA transfection and piroxicam treatment. Blockage of PPARα by siRNA transfection inhibited UII-induced Akt phosphorylation and the antiapoptotic effect of UII. Our results suggest that UII can protect renal tubular cells from gentamicin-induced apoptosis through PGI2-mediated PPARα and Akt activation.

Effects of maltitol and xylitol chewing-gums on parameters involved in dental caries development

AIM

The effects on plaque parameters of sugar free chewing-gums (CG) sweetened with either maltitol or xylitol were assessed to better understand the role polyols can play in dental caries prevention.

MATERIALS AND METHODS

A double-blind, parallel, randomised, controlled study was conducted in China. Subjects (N = 258, age = 13 to 15 years-old) were divided into 4 groups: 2 receiving polyols CG, containing respectively maltitol or xylitol, a group receiving gum base (placebo) and a negative control group not receiving any gum. CG were chewed for 30 days. This corresponds to a 10 g consumption of polyol per day. Plaque parameters (growth, pH, bacteria and insoluble glucans) were evaluated throughout the experimental period.

RESULTS

All parameters studied were significantly modified with gum base compared to no-gum: plaque pH increased; plaque growth, bacteria (S. mutans, S. sobrinus, A. viscosus and Lactobacillus) and insoluble glucans decreased. Maltitol and xylitol CG led similarly to a higher plaque pH (AUC, p⋜0.05) on short (at baseline after the first CG consumption) and long term (after 4 weeks of daily CG consumption), with or without saliva stimulation compared to both control and placebo groups. They led to a decrease in plaque growth (p=0.02) over the experimental period compared to controls. Moreover, they significantly reduced the concentration of 4 cariogenic bacteria species (p⋜0.05) in dental plaque compared to gum base.

CONCLUSION

Sugar free CG sweetened with either maltitol or xylitol can similarly reduce plaque acidogenicity compared to gum base through a decrease in oral bacteria presence. The use of a gum base placebo allowed to isolate effects on parameters involved in dental caries development specific to maltitol and xylitol, and to show these effects were similar.

Vertebral osteomyelitis caused by vancomycin-tolerant methicillin-resistant Staphylococcus aureus bacteremia: Experience with teicoplanin plus fosfomycin combination therapy

An 85-year-old female presented with fever and consciousness disturbance for 3 days. The patient's blood culture subsequently revealed persistent methicillin-resistant Staphylococcus aureus (MRSA) bacteremia despite the administration of vancomycin or teicoplanin monotherapy. Gallium inflammation scan and magnetic resonance image of the spine disclosed osteomyelitis and discitis at the level of L4-5. Surgical debridement was not feasible in this debilitated patient. Because of the creeping minimal inhibitory concentration of vancomycin of the causative isolate (1.5 μg/mL) and clinical failure with glycopeptide monotherapy, we changed the antibiotic therapy to a fosfomycin and teicoplanin combination therapy. The patient showed improved clinical response in terms of her enhanced consciousness as well as subsidence of persisted bacteremia. Despite the potential side effects of fosfomycin (such as diarrhea and hypernatremia), it combined with a glycopeptide may be an alternative therapy for invasive refractory MRSA infections.

Successful treatment of drug-induced acute liver failure with high-volume plasma exchange

We report two patients with drug-induced liver injury (DILI)-related acute liver failure (ALF) who were successfully treated with high-volume plasma exchange without liver transplantation. The first patient was a 66-year-old man admitted because of a perforated duodenal ulcer complicated with peritonitis and septic shock. After treatment with multiple antibiotics, the patient developed DILI and ALF. Grade 3 hepatic encephalopathy and profound jaundice were present. Symptoms and signs of ALF improved dramatically after initiation of plasma exchange. The patient was discharged uneventfully. The second patient was a 94-year-old man admitted for treatment of newly diagnosed pulmonary tuberculosis. DILI and ALF developed 5 days after initiation of anti-tuberculosis treatment. Grade 4 hepatic encephalopathy was present. After plasma exchange, the patient's level of consciousness improved dramatically, and he recovered from ALF. These 2 cases show the potential of plasma exchange in the treatment of DILI despite occurrence acute liver failure.

Rosuvastatin inhibits pressure-induced fibrotic responses via the expression regulation of prostacyclin and prostaglandin E2 in rat renal tubular cells

Statins are reported to alleviate renal fibrosis in animal models with ureteral obstruction. However, the molecular mechanism of this antifibrotic effect is still unclear. Pressure force is an important mechanism contributing to induction and progression of tubulointerstitial fibrogenesis in ureteric obstruction. In this study, we investigated the influence of rosuvastatin on pressure-induced fibrotic responses in rat renal tubular cells (NRK-52E). We established an in vitro pressure culture system to study pressure-induced fibrotic responses in NRK-52E cells. When NRK-52E cells were cultured in the pressure culture system, 60 mm Hg of pressure induced the expression of connective tissue growth factor (CTGF), transforming growth factor (TGF)-β, fibronectin, Smad3, and phospho-Smad3. Rosuvastatin significantly reduced these pressure-induced fibrotic responses at concentrations above 10 μM. Rosuvastatin also reduced the TGF-β-induced expression of fibronectin and CTGF in NRK-52E cells. Pretreatment with rosuvastatin significantly induced prostacyclin (PGI(2)) generation, but reduced pressure-induced prostaglandin E(2) (PGE(2)). PGI(2) synthase small interfering RNA (siRNA) transfection significantly inhibited rosuvastatin-induced peroxisome proliferator-activated receptor α activation. The blockage of peroxisome proliferator-activated receptor α by siRNA transfection reduced the inhibitory effect of rosuvastatin on pressure-induced fibrotic responses. N-[2-(cyclohexyloxy)-4-nitrophenyl]-methanesulfonamide (NS398), a specific inhibitor of cyclooxygenase-2, diminished pressure-induced PGE(2) generation, and also reduced pressure-induced fibrotic responses. Additionally, PGE(2) decreased the antifibrotic effect of rosuvastatin. In conclusion, rosuvastatin reduces pressure-induced fibrotic responses in renal tubular cells by enhancing the PGI(2)-peroxisome proliferator-activated receptor α pathway and reducing PGE(2) generation.

The secreted Klotho protein restores phosphate retention and suppresses accelerated aging in Klotho mutant mice

Klotho was identified as the responsible gene in a mutant mouse line whose disruption results in a variety of premature aging-related phenotypes. Nonetheless, the related mechanisms were still unknown. Many studies report that dietary phosphate restriction and genetic ablation of vitamin D pathways indirectly reverse premature aging processes in these mice. Furthermore, transgenic overexpression of klotho in mice extends their life span through inhibition of insulin and IGF1 signaling. We found that intraperitoneal injection of recombinant soluble Klotho protein at dose of 0.02 mg/kg every other day effectively extends the life span of kl/kl mice by 17.4%. Soluble Klotho administration also ameliorated premature aging-related phenotype, such as growth retardation, premature thymus involution and vascular calcification, and effectively enhanced urinary phosphate excretion in kl/kl mice. Klotho treatment attenuated renal fibrosis through down-regulation of transforming growth factor-β signaling as well as reduced cellular senescence through down-regulation of p21-cip1 mRNA levels. In addition, soluble Klotho treatment significantly reduced both renal and aorta calcium deposits. In conclusion, our study shows the therapeutic potential of soluble Klotho protein to treat age-related disorders in mice.

Polarity proteins and actin regulatory proteins are unlikely partners that regulate cell adhesion in the seminiferous epithelium during spermatogenesis

In mammalian testis, spermatogenesis takes place in the seminiferous epithelium of the seminiferous tubule, which is composed of a series of cellular events. These include: (i) spermatogonial stem cell (SSC) renewal via mitosis and differentiation of SSC to spermatogenia, (ii) meiosis, (iii) spermiogenesis, and (iv) spermiation. Throughout these events, developing germ cells remain adhered to the Sertoli cell in the seminiferous epithelium amidst extensive cellular, biochemical, molecular and morphological changes to obtain structural support and nourishment. These events are coordinated via signal transduction at the cell-cell interface through cell junctions, illustrating the significance of cell junctions and adhesion in spermatogenesis. Additionally, developing germ cells migrate progressively across the seminiferous epithelium from the stem cell niche, which is located in the basal compartment near the basement membrane of the tunica propria adjacent to the interstitium. Recent studies have shown that some apparently unrelated proteins, such as polarity proteins and actin regulatory proteins, are in fact working in concert and synergistically to coordinate the continuous cyclic changes of adhesion at the Sertoli-Sertoli and Sertoli-germ cell interface in the seminiferous epithelium during the epithelial cycle of spermatogenesis, such that developing germ cells remain attached to the Sertoli cell in the epithelium while they alter in cell shape and migrate across the epithelium. In this review, we highlight the physiological significance of endocytic vesicle-mediated protein trafficking events under the influence of polarity and actin regulatory proteins in conferring cyclic events of cell adhesion and de-adhesion. Furthermore, these recent findings have unraveled some unexpected molecules to be targeted for male contraceptive development, which are also targets of toxicant-induced male reproductive dysfunction.

Coexistence of exchange bias and magnetization pinning in the MnO(x)/GaMnAs system

Coexistence of exchange bias (H(E)) and magnetization (M) shift was observed in as-grown and field-annealed MnO(x)/Ga(0.95)Mn(0.05)As bilayers. It was found that H(E) initially decreases with the annealing time t(a) and then increases when t(a) > 30 min, while the M shift remains almost unchanged with t(a). X-ray photoelectron spectroscopy (XPS) analysis reveals that MnO(x) is composed of MnO and Mn(3)O(4), and the volume amount ratio of Mn(3)O(4) to MnO increases with increasing t(a). A simple model based on a uniform MnO-Mn(3)O(4) interface with constant 'pinned' uncompensated interfacial spins is proposed to account for the observed exchange-biased phenomena in the bilayers.

Spermatogonial stem cells alone are not sufficient to re-initiate spermatogenesis in the rat testis following adjudin-induced infertility

The blood-testis barrier (BTB) is a unique ultrastructure in the testis, which creates a specialized microenvironment in the seminiferous epithelium known as the apical (or adluminal) compartment for post-meiotic germ-cell development and for maintenance of an immunological barrier. In this study, we have demonstrated unequivocally that a functional and intact BTB is crucial for the initiation of spermatogenesis, in particular, the differentiation of spermatogonial stem cells (SSCs). It was shown that adult rats (∼300 g body weight, b.w.) treated with adjudin at 50 (low-dose) or 250 (high-dose) mg/kg b.w. by gavage led to germ-cell depletion from the seminiferous tubules and that >98% of the tubules were devoid of germ cells by ∼2 week and rats became infertile in both groups after the sperm reserve in the epididymis was exhausted. While the population of SSC/spermatogonia in the seminiferous tubules from both groups was similar to that of normal rats, only rats from the low-dose group were capable of re-initiating spermatogenesis; and by 20 weeks, greater than 75% of the tubules displayed normal spermatogenesis and the fertility of these rats rebounded. Detailed analysis by dual-labelled immunofluorescence analysis and a functional BTB integrity assay revealed that in both treatment groups, the BTB was disrupted from week 6 to week 12. However, the disrupted BTB 'resealed' in the low-dose group, but not in the high-dose group. Our findings illustrate that SSC/spermatogonia failed to differentiate into spermatocytes beyond A(aligned) spermatogonia in the high-dose group with a disrupted BTB. In short, these findings illustrate the critical significance of the BTB for re-initiation of spermatogenesis besides SSC and spermatogonia.

Fate and distribution of nitrogen in soil and plants irrigated with landfill leachate

Landfill leachate contains a high concentration of ammoniacal substances which can be a potential supply of N for plants. A bioassay was conducted using seeds of Brassica chinensis and Lolium perenne to evaluate the phytotoxicity of the leachate sample. A soil column experiment was then carried out in a greenhouse to study the effect of leachate on plant growth. Two grasses (Paspalum notatum and Vetiver zizanioides) and two trees (Hibiscus tiliaceus and Litsea glutinosa) were irrigated with leachate at the EC50 levels for 12 weeks. Their growth performance and the distribution of N were examined and compared with columns applied with chemical fertilizer. With the exception of P. notatum, plants receiving leachate and fertilizer grew better than those receiving water alone. The growth of L. glutinosa and V. zizanioides with leachate irrigation did not differ significantly from plants treated with fertilizer. Leachate irrigation significantly increased the levels of NH(x)-N in soil. Although NO(x)-N was below 1 mg NL(-1) in the leachate sample, the soil NO(x)-N content increased by 9-fold after leachate irrigation, possibly as a result of nitrification. Leachate irrigation at EC50 provided an N input of 1920 kg N ha(-1) over the experimental period, during which up to 1050 kg N ha(-1) was retained in the soil and biomass, depending on the type of vegetation. The amount of nutrient added seems to exceed beyond the assimilative capability. Practitioners should be aware of the possible consequence of N saturation when deciding the application rate if leachate irrigation is aimed for water reuse.