Rapid and high throughput assessment of cellular immunity against SARS-CoV-2 based on the ex vivo activation of genes in leukocyte assay with whole blood.

During the novel coronavirus outbreak and vaccine development, antibody production garnered major focus as the primary immunogenic response. However, cellular immunity's recent demonstration of comparable or greater significance in controlling infection demands the re-evaluation of the importance of T-cell immunity in SARS-CoV-2 infection. Here, we developed a novel assay, the ex vivo activation of genes in leukocytes (EAGL), which employs short-term whole blood stimulation with the LeukoComplete™ system, to measure ex vivo SARS-CoV-2-specific T cell responses (cellular immunity). This assay measures upregulated mRNA expression related to leukocyte activation 4 h after antigen stimulation. LeukoComplete™ system uses whole blood samples, eliminating the need for pretreatment before analysis. Furthermore, this system's high reproducibility is ensured through a series of operations from mRNA extraction to cDNA synthesis on a 96-well plate. In the performance evaluation using fresh blood from previously SARS-CoV-2-infected and COVID-19-vaccinated individuals, the EAGL assay had a comparable sensitivity and specificity to the ELISpot assay (EAGL: 1.000/1.000; ELISpot: 0.900/0.973). As a simple, high-throughput assay, the EAGL assay is also a quantitative test that is useful in studies with large sample numbers, such as monitoring new vaccine efficacies against novel coronaviruses or epidemiologic studies that require cellular immune testing during viral infection.

Development and nationwide validation of kidney graft injury markers using urinary exosomes and microvesicles (complete English translation of the Japanese version).

BACKGROUND: Non-invasive, prompt, and proper detection tools for kidney graft injuries (KGIs) are awaited to ensure graft longevity. We screened diagnostic biomarkers for KGIs following kidney transplantation using extracellular vesicles (EVs; exosomes and microvesicles) from the urine samples of patients. METHODS: One hundred and twenty-seven kidney recipients at 11 Japanese institutions were enrolled in this study; urine samples were obtained prior to protocol/episode biopsies. EVs were isolated from urine samples, and EV RNA markers were assayed using quantitative reverse transcription polymerase chain reaction. Diagnostic performance of EV RNA markers and diagnostic formulas comprising these markers were evaluated by comparison with the corresponding pathological diagnoses. RESULTS: EV CXCL9, CXCL10, and UMOD were elevated in T-cell-mediated rejection samples compared with other KGI samples, while SPNS2 was elevated in chronic antibody-mediated rejection (cABMR) samples. A diagnostic formula developed through Sparse Logistic Regression analysis using EV RNA markers allowed us to accurately (with an area under the receiver operator characteristic curve [AUC] of 0.875) distinguish cABMR from other KGI samples. EV B4GALT1 and SPNS2 were also elevated in cABMR, and a diagnostic formula using these markers was able to distinguish between cABMR and chronic calcineurin toxicity accurately (AUC 0.886). In interstitial fibrosis and tubular atrophy (IFTA) urine samples and those with high Banff chronicity score sums (BChS), POTEM levels may reflect disease severity, and diagnostic formulas using POTEM detected IFTA (AUC 0.830) and high BChS (AUC 0.850). CONCLUSIONS: KGIs could be diagnosed with urinary EV mRNA analysis with relatively high accuracy.

The effectiveness of simulation-based education combined with peer-assisted learning on clinical performance of first-year medical residents: a case-control study.

BACKGROUND: Simulation-based education and peer-assisted learning (PAL) are both known as useful educational methods. Previous research has reported that combining these two methods are effective for training medical residents in short-term evaluation. This study was aimed to evaluate the middle- to long-term effects of simulation-based education combined with PAL on the performance of medical residents during emergency department duties. METHODS: This study was designed as a case-control study and conducted over three years at Okayama University Hospital in Japan. Postgraduate-year-one medical residents were assigned to three groups: a simulation group that received simulation-based education, a lecture group that received traditional lecture-based education, and a control group that received no such prior trainings. Prior training in emergency department duties using PAL was performed as an educational intervention for the simulation and lecture groups during the clinical orientation period. The residents' medical knowledge was assessed by written examinations before and after the orientation. The performance of residents during their emergency department duties was assessed by self-evaluation questionnaires and objective-assessment checklists, following up with the residents for three months after the orientation period and collecting data on their 1st, 2nd, and 3rd emergency department duties. All the datasets collected were statistically analyzed and compared by their mean values among the three groups. RESULTS: A total of 75 residents were included in the comparative study: 27 in the simulation group, 24 in the lecture group, and 24 in the control group. The simulation and lecture groups obtained significantly higher written examination scores than the control group. From the self-evaluation questionnaires, the simulation group reported significantly higher satisfaction in their prior training than the lecture group. No significant differences were found in the emergency department performance of the residents among the three groups. However, when evaluating the improvement rate of performance over time, all three groups showed improvement in the subjective evaluation, and only the simulation and lecture groups showed improvement in the objective evaluation. CONCLUSION: Simulation-based education combined with PAL is effective in improving the knowledge and satisfaction of medical residents, suggesting the possibility of improving work performance during their emergency department duties.

Bleeding patterns of women with heavy menstrual bleeding or dysmenorrhoea using the levonorgestrel-releasing intrauterine system: results from a real-world observational study in Japan (J-MIRAI).

PURPOSE: To collect real-world safety and clinical outcome data on the levonorgestrel-releasing intrauterine system (LNG-IUS) for functional/organic heavy menstrual bleeding (HMB) and dysmenorrhoea in Japanese women (J-MIRAI). MATERIALS AND METHODS: In this prospective, multicentre, single-cohort, open-label, post-authorisation study, we assessed menstrual blood loss after LNG-IUS insertion by changes from baseline in pictorial blood loss assessment chart (PBAC) scores. Scores for the menorrhagia multi-attribute scale (MMAS) were collected for 12 months to assess quality of life. RESULTS: We included 47 patients with complete PBAC score and patient diary data. The median PBAC score before LNG-IUS insertion was 159.0, which decreased significantly to 6.0 at 12 months post-insertion; for patients with adenomyosis (n = 20), PBAC score decreased from 174.5 pre-insertion to 19.5 at 12 months. The number of patient-reported bleeding days was correlated with PBAC score ≥5. The proportion of women with prolonged bleeding decreased from 85.7% to 34.6% by the study's end. Some women reported no bleeding after the first 90-day reference period. The mean MMAS overall score significantly increased from 50.50 before insertion to 88.67 at 12 months. CONCLUSIONS: Japanese women with functional/organic HMB experienced substantial reductions in bleeding symptoms and improvements in quality of life after 12-month use of the LNG-IUS.

CA1 LTP Attenuated by Corticosterone is Canceled by Effusol via Rescuing Intracellular Zn2+ Dysregulation.

Exposure to corticosterone attenuates hippocampal CA1 long-term potentiation (LTP) via intracellular Zn2+ dysregulation. Here we report that effusol, a phenanthrene isolated from Chinese medicine Juncus effusus, rescues CA1 LTP attenuated by corticosterone. In vivo microdialysis experiment indicated that both increases in extracellular glutamate induced under perfusion with corticosterone and high K+ are suppressed in the hippocampus by co-perfusion with effusol. Because corticosterone and high K+ also increase extracellular Zn2+ level, followed by intracellular Zn2+ dysregulation, the effect of effusol on both the increases was examined in brain slice experiments. Effusol did not suppress increase in extracellular Zn2+ in the hippocampal CA1 of brain slices bathed in corticosterone, but suppressed increase in intracellular Zn2+, which may be linked with suppressing the increase in extracellular glutamate in vivo. In vivo CA1 LTP was attenuated under perfusion with corticosterone prior to LTP induction, while the attenuation was rescued by co-perfusion with effusol, suggesting that the rescuing effect of effusol is due to suppressing the increase in intracellular Zn2+ in CA1 pyramidal cells. The present study indicates that CA1 LTP attenuated by corticosterone is canceled by effusol, which rescues intracellular Zn2+ dysregulation via suppressing extracellular glutamate accumulation. It is likely that effusol defends the hippocampal function against stress-induced cognitive decline.

Effects on postgraduate-year-I residents of simulation-based learning compared to traditional lecture-style education led by postgraduate-year-II residents: a pilot study.

BACKGROUND: Simulation-based learning plays an important role in contemporary medical education, although there are problems providing tutors. Peer-assisted learning has begun being formally adopted in medical education. Although it is considered useful for simulation-based learning, its effectiveness remains unclear. This study was designed to compare the effect of simulation-based learning with that of traditional lectures conducted by postgraduate-year (PGY)-II residents on PGY-I residents. METHODS: This study was conducted at Okayama University Hospital over three years, for one week each year, before residents entered clinical practice. The study enrolled 76 PGY-I residents, who were randomized into two groups: simulation and lecture groups. PGY-II residents volunteered to conduct simulations and lectures. Knowledge evaluation was performed using pre- and post-tests, and self-evaluation of competence and behaviour-change and program evaluations were conducted using questionnaires. RESULTS: In both groups, knowledge test scores were found to improve significantly, and the score difference between pre- and post-tests in both the groups was not significant. Self-evaluation of competence and behaviour-change was found to be higher in the simulation group than the lecture group. The trainees in the simulation group valued the program and the PGY-II residents as teaching staff more than those in the lecture group. CONCLUSIONS: The combination of simulation-based learning and peer-assisted learning led by PGY-II residents is potentially more effective in improving the postgraduate education of PGY-I residents than the combination of lecture and peer-assisted learning.

Uromodulin mRNA from Urinary Extracellular Vesicles Correlate to Kidney Function Decline in Type 2 Diabetes Mellitus.

BACKGROUND: Extracellular vesicles (EVs) enclose mRNA derived from their cell of origin and are considered a source of potential biomarkers. We examined urinary EV mRNA from individuals with diabetic kidney disease (DKD), chronic kidney disease, type 2 diabetes (T2DM), and obese and healthy controls to determine if such biomarkers had the potential to classify kidney disease and predict patients at higher risk of renal function decline. METHODS: A total of 242 participants enrolled in this study. Urinary EV mRNA from all subjects were isolated by a filter-based platform, and the expression of 8 target genes were determined by quantitative polymerase chain reaction (qPCR). Changes in estimated glomerular filtration rate (eGFR) in 161 T2DM patients were evaluated for 2 consecutive years and compared with EV RNA profiles at baseline. RESULTS: We observe that mild and severe DKD groups show a significant 3.2- and -4.4-fold increase in UMOD compared to healthy controls and expression increases linearly from healthy, diabetic, and DKD subjects. UMOD expression is significantly correlated to albumin creatinine ratio (ACR), eGFR, and HbA1c. Using linear discriminant analyses with mRNA from severe DKD and T2DM as training data, a multi-gene signature classified DKD and -non-DKD with a sensitivity of 93% and specificity of 73% with area under the receiver operating characteristic (ROC) curve (AUC) = 0.90. Although 6% of T2DM were determined to have a > 80% posterior probability of developing DKD based on this mRNA profile, eGFR changes observed within the 2-year follow-up did not reveal a decline in kidney function. CONCLUSION: Urinary EV UMOD mRNA levels are progressively elevated from T2DM to DKD groups and correlate with widely used eGFR and ACR diagnostic criteria. An EV mRNA signature could identify DKD with greater than 90% sensitivity and 70% specificity.

Behavioral Abnormality Induced by Enhanced Hypothalamo-Pituitary-Adrenocortical Axis Activity under Dietary Zinc Deficiency and Its Usefulness as a Model.

Dietary zinc deficiency increases glucocorticoid secretion from the adrenal cortex via enhanced hypothalamo-pituitary-adrenocortical (HPA) axis activity and induces neuropsychological symptoms, i.e., behavioral abnormality. Behavioral abnormality is due to the increase in glucocorticoid secretion rather than disturbance of brain zinc homeostasis, which occurs after the increase in glucocorticoid secretion. A major target of glucocorticoids is the hippocampus and their actions are often associated with disturbance of glutamatergic neurotransmission, which may be linked to behavioral abnormality, such as depressive symptoms and aggressive behavior under zinc deficiency. Glucocorticoid-mediated disturbance of glutamatergic neurotransmission in the hippocampus is also involved in the pathophysiology of, not only psychiatric disorders, such as depression, but also neurodegenerative disorders, e.g., Alzheimer's disease. The evidence suggests that zinc-deficient animals are models for behavioral and psychological symptoms of dementia (BPSD), as well as depression. To understand validity to apply zinc-deficient animals as a behavioral abnormality model, this paper deals with the effect of antidepressive drugs and herbal medicines on hippocampal dysfunctions and behavioral abnormality, which are induced by enhanced HPA axis activity under dietary zinc deficiency.

Posttransplantation bone marrow assessment by quantifying hematopoietic cell-derived mRNAs in plasma exosomes/microvesicles.

BACKGROUND: Bone marrow (BM) aspiration often can be a painful medical procedure. It is unavoidable, however, because hematopoietic precursor cells (HPC) exist only in BM and few escape to peripheral blood (PB). We hypothesized that HPCs might release exosomes and microvesicles (EMV) in BM, and the resulting EMV would penetrate into PB. Such BM-derived EMV might be identified in PB by measuring specific mRNAs produced by HPC. METHODS: Human plasma was applied to an EMV-capture filter plate. After centrifugation, captured EMV were lysed on the filter plate. Resulting lysates were transferred to an oligo(dT)-immobilized microplate for mRNA isolation followed by reverse transcription PCR (RT-PCR). Using this system, myeloid-, erythroid-, and megakaryocyte-lineage-specific poly(A)(+) mRNAs were quantified in plasma obtained from 18 patients who had undergone hematopoietic stem cell transplantation (HSCT). RESULTS: When fluorescent liposomes were applied to the filter plate, more than 95% of applied liposomes were absorbed. When human plasma was applied, a scanning electron microscope showed EMV-like particles on the membrane of the filter plate. After RT-PCR, various HPC-specific mRNAs were detected, and the results were equivalent to those derived from the standard ultracentrifugation method. The levels of these mRNAs were undetectable after HSCT and became detectable 1-2 weeks after HSCT, a substantially earlier time point than with traditional hematological analysis. The recovery of EMV mRNA at day 15 corresponded to the final clinical outcome at day 180. CONCLUSIONS: HPC-derived mRNAs in plasma EMV may represent new biomarkers for the assessment of BM condition and could reduce the necessity for frequent BM aspiration.

Sensitive RNA detection by combining three-way junction formation and primer generation-rolling circle amplification.

Recently, we developed a simple isothermal nucleic acid amplification reaction, primer generation-rolling circle amplification (PG-RCA), to detect specific DNA sequences with great sensitivity and large dynamic range. In this paper, we combined PG-RCA with a three-way junction (3WJ) formation, and detected specific RNA molecules with high sensitivity and specificity in a one-step and isothermal reaction format. In the presence of target RNA, 3WJ probes (primer and template) are designed to form a 3WJ structure, from which multiple signal primers for the following PG-RCA can be generated by repeating primer extension, nicking and signal primer dissociation. Although this signal primer generation is a linear amplification process, the PG-RCA exponentially can amplify these signal primers and thus even a very small amount of RNA specimen can be detected. After optimizing the structures of 3WJ probes, the detection limit of this assay was 15.9 zmol (9.55 × 10(3) molecules) of synthetic RNA or 143 zmol (8.6 × 10(4) molecules) of in vitro transcribed human CD4 mRNA. Further, the applicability of this assay to detect CD4 mRNA in a human mRNA sample was demonstrated.

Cross-sectional and longitudinal analyses of urinary extracellular vesicle mRNA markers in urothelial bladder cancer patients.

We designed this multi-center prospective study with the following objectives: (1) the cross-sectional validation of extracellular vesicles (EV) mRNA markers to detect urothelial bladder cancer (UBC) before transurethral resection of bladder cancer (TURBT), and (2) the longitudinal validation of EV mRNA markers to monitor non-muscle invasive bladder cancer (NMIBC) recurrence after TURBT. EV mRNA markers evaluated in this study were KRT17, GPRC5A, and SLC2A1 in addition to two additional markers from literatures, MDK and CXCR2, and measured by quantitative RT-PCR with normalization by a reference gene (ALDOB). Diagnostic performances of EV mRNA markers were compared to conventional markers. Regarding the first objective, we confirmed that EV mRNA biomarkers in urine were higher in UBC patients, particularly those with higher stage/grade tumors, than in those without UBC (n = 278 in total) and the diagnostic performance of EV mRNA MDK and KRT17 outperformed conventional biomarkers with AUC 0.760 and 0.730, respectively. Concerning the second objective, we prospectively analyzed the time courses of EV mRNA markers while NMIBC patients (n = 189) (median follow-up 19 months). The expression of EV mRNA KRT17 was significantly high in patients with recurrence, while it gradually decreased over time in those without recurrence (p < 0.01).

Hypercalcemia Associated with the Ectopic Expression of 25-hydroxyvitamin D3-1α-hydroxylase in Diffuse Large B-cell Lymphoma.

An 82-year-old man was transferred to our hospital due to impaired consciousness. His albumin-corrected calcium level was 14.2 mg/dL, intact parathyroid hormone (PTH) and PTH-related protein levels were reduced, and his 1,25-dihydroxyvitamin D [1,25 (OH) 2VitD] level was elevated at 71.5 pg/mL. Computed tomography revealed masses on the bilateral ribs. The mass on the rib was biopsied and diagnosed as diffuse large B-cell lymphoma (DLBCL). Immunostaining of the biopsy sample with the anti-CYP27B1 antibody revealed the ectopic expression of 1α-hydroxylase in the lesion. We herein report a rare case of hypercalcemia induced by the overproduction of 1,25 (OH) 2VitD in DLBCL ectopically expressing 1α-hydroxylase.

Sensitive isothermal detection of nucleic-acid sequence by primer generation-rolling circle amplification.

A simple isothermal nucleic-acid amplification reaction, primer generation-rolling circle amplification (PG-RCA), was developed to detect specific nucleic-acid sequences of sample DNA. This amplification method is achievable at a constant temperature (e.g. 60 degrees C) simply by mixing circular single-stranded DNA probe, DNA polymerase and nicking enzyme. Unlike conventional nucleic-acid amplification reactions such as polymerase chain reaction (PCR), this reaction does not require exogenous primers, which often cause primer dimerization or non-specific amplification. Instead, 'primers' are generated and accumulated during the reaction. The circular probe carries only two sequences: (i) a hybridization sequence to the sample DNA and (ii) a recognition sequence of the nicking enzyme. In PG-RCA, the circular probe first hybridizes with the sample DNA, and then a cascade reaction of linear rolling circle amplification and nicking reactions takes place. In contrast with conventional linear rolling circle amplification, the signal amplification is in an exponential mode since many copies of 'primers' are successively produced by multiple nicking reactions. Under the optimized condition, we obtained a remarkable sensitivity of 84.5 ymol (50.7 molecules) of synthetic sample DNA and 0.163 pg (approximately 60 molecules) of genomic DNA from Listeria monocytogenes, indicating strong applicability of PG-RCA to various molecular diagnostic assays.

mRNAs in urinary nano-extracellular vesicles as potential biomarkers for non-invasive kidney biopsy.

Urinary nano-extracellular vesicles (NVs), including exosomes and microvesicles, are considered potential biomarkers for kidney diseases using liquid biopsies. However, clinical application of urinary NVs has not yet been validated. In the present study, the levels of mRNAs in urinary NVs in animal models of kidney disease were assessed. Urine samples were collected from the animal models and urinary NVs were isolated by ultracentrifugation. Gene expression levels of kidney injury markers in urinary NVs and renal tissue were quantified by reverse transcription-quantitative PCR. The mRNA levels of desmin, a podocyte injury marker, in urinary NVs was markedly increased in the puromycin aminonucleoside (PAN) nephritis model, in parallel with enhanced desmin expression in kidney tissues. The expression of regulator of calcineurin 1 and the podocin to nephrin ratio (PNR) were also increased in the PAN nephritis model. Treatment with prednisolone mitigated these changes in gene expression as well as proteinuria. PNR, which is considered a predictive marker of glomerular dysfunction, in urinary NVs was highly correlated with urinary protein excretion (P<0.01). Furthermore, PNR in urinary NVs of Zucker diabetic fatty rats, a diabetic kidney disease model, was correlated with urinary albumin excretion (P<0.01). These results suggest that changes in mRNA levels of urinary NVs reflect the disease status of kidney tissues and their functional alterations. Collectively, mRNA analysis of urinary NVs may be used as a liquid biopsy tool for improved classification and performance of risk prediction to determine the severity of kidney diseases.

Preferential Neurodegeneration in the Dentate Gyrus by Amyloid ß1-42-Induced Intracellular Zn2+Dysregulation and Its Defense Strategy.

On the basis of the evidence that rapid intracellular Zn2+ dysregulation by amyloid ß1-42 (Aß1-42) in the normal hippocampus transiently induces cognitive decline, here we report preferential neurodegeneration in the dentate gyrus by Aß1-42-induced intracellular Zn2+ dysregulation and its defense strategy. Neurodegeneration was preferentially observed in the dentate granule cell layer in the hippocampus after a single Aß1-42 injection into the lateral ventricle but not in the CA1 and CA3 pyramidal cell layers, while intracellular Zn2+ dysregulation was extensively observed in the hippocampus in addition to the dentate gyrus. Neurodegeneration in the dentate granule cell layer was rescued after co-injection of extracellular and intracellular Zn2+ chelators, i.e., CaEDTA and ZnAF-2DA, respectively. Aß1-42-induced cognitive impairment was also rescued by co-injection of CaEDTA and ZnAF-2DA. Pretreatment with dexamethasone, an inducer of metalothioneins, Zn2+-binding proteins rescued neurodegeneration in the dentate granule cell layer and cognitive impairment via blocking the intracellular Zn2+ dysregulation induced by Aß1-42. The present study indicates that intracellular Zn2+ dysregulation induced by Aß1-42 preferentially causes neurodegeneration in the dentate gyrus, resulting in hippocampus-dependent cognitive decline. It is likely that controlling intracellular Zn2+ dysregulation, which is induced by the rapid uptake of Zn-Aß1-42 complexes, is a defense strategy for Alzheimer's disease pathogenesis.

Amyloid ß1-42-Induced Rapid Zn2+ Influx into Dentate Granule Cells Attenuates Maintained LTP Followed by Retrograde Amnesia.

On the basis of the evidence that amyloid ß1-42 (Aß1-42)-induced Zn2+ influx affects memory acquisition via attenuated long-term potentiation (LTP) induction, here we tested whether Aß1-42-induced Zn2+ influx affects maintained LTP in freely moving rats, resulting in retrograde amnesia. Both maintained LTP and space memory were impaired by local injection of 250 µM ZnCl2 (2 µl) into the dentate gyrus, while maintained LTP was impaired by injection of either Aß1-40 or Aß1-42 (25 µM, 2 µl) into the dentate gyrus. Aß1-40-induced impairment of maintained LTP was rescued by co-injection of CaEDTA, an extracellular Zn2+ chelator, but not by co-injection of ZnAF-2DA, an intracellular Zn2+ chelator, suggesting that maintained LTP is impaired by Aß1-40 via a mechanism that may involve extracellular Zn2+. In contrast, Aß1-42-induced impairments of maintained LTP and space memory were rescued by co-injection of either CaEDTA or ZnAF-2DA. Intracellular Zn2+ in dentate granule cells was rapidly increased by Aß1-42 injection into the dentate gyrus, but not by Aß1-40 injection. The block of Aß1-42-induced increase in intracellular Zn2+ by pretreatment with dexamethasone, a metallothionein inducer also rescued Aß1-42-induced impairment of maintained LTP. The present study indicates that Aß1-42-induced Zn2+ influx into dentate granule cells, which more readily occurs than free Zn2+-induced Zn2+ influx, attenuates maintained LTP followed by retrograde amnesia. It is likely that controlling Aß1-42-induced intracellular Zn2+ dysregulation is a strategy for defending AD pathogenesis.

Maintained LTP and Memory Are Lost by Zn2+ Influx into Dentate Granule Cells, but Not Ca2+ Influx.

The idea that maintained LTP and memory are lost by either increase in intracellular Zn2+ in dentate granule cells or increase in intracellular Ca2+ was examined to clarify significance of the increases induced by excess synapse excitation. Both maintained LTP and space memory were impaired by injection of high K+ into the dentate gyrus, but rescued by co-injection of CaEDTA, which blocked high K+-induced increase in intracellular Zn2+ but not high K+-induced increase in intracellular Ca2+. High K+-induced disturbances of LTP and intracellular Zn2+ are rescued by co-injection of 6-cyano-7-nitroquinoxakine-2,3-dione, an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor antagonist, but not by co-injection of blockers of NMDA receptors, metabotropic glutamate receptors, and voltage-dependent calcium channels. Furthermore, AMPA impaired maintained LTP and the impairment was also rescued by co-injection of CaEDTA, which blocked increase in intracellular Zn2+, but not increase in intracellular Ca2+. NMDA and glucocorticoid, which induced Zn2+ release from the internal stores, did not impair maintained LTP. The present study indicates that increase in Zn2+ influx into dentate granule cells through AMPA receptors loses maintained LTP and memory. Regulation of Zn2+ influx into dentate granule cells is more critical for not only memory acquisition but also memory retention than that of Ca2+ influx.

Weakened Intracellular Zn2+-Buffering in the Aged Dentate Gyrus and Its Involvement in Erasure of Maintained LTP.

Memory is lost by the increased influx of extracellular Zn2+ into neurons. It is possible that intracellular Zn2+ dynamics is modified even at non-zincergic medial perforant pathway-dentate granule cell synapses along with aging and that vulnerability to the modification is linked to age-related cognitive decline. To examine these possibilities, vulnerability of long-term potentiation (LTP) maintenance, which underlies memory retention, to modification of synaptic Zn2+ dynamics was compared between young and aged rats. The influx of extracellular Zn2+ into dentate granule cells was increased in aged rats after injection of high K+ into the dentate gyrus, but not in young rats. This increase impaired maintained LTP in aged rats. However, the impairment was rescued by co-injection of CaEDTA, an extracellular Zn2+ chelator, or CNQX, an AMPA receptor antagonist, which suppressed the Zn2+ influx. Maintained LTP was also impaired in aged rats after injection of ZnAF-2DA into the dentate gyrus that chelates intracellular Zn2+, but not in young rats. Interestingly, the capacity of chelating intracellular Zn2+ with intracellular ZnAF-2 was almost lost in the aged dentate gyrus 2 h after injection of ZnAF-2DA into the dentate gyrus, suggesting that intracellular Zn2+-buffering is weakened in the aged dentate gyrus, compared to the young dentate gyrus. In the dentate gyrus of aged rats, maintained LTP is more vulnerable to modification of intracellular Zn2+ dynamics than in young rats, probably due to weakened intracellular Zn2+-buffering.

Comparison of benign peritoneal fluid- and ovarian cancer ascites-derived extracellular vesicle RNA biomarkers.

BACKGROUND: Extracellular vesicles (EVs) are considered as a new class of resources for potential biomarkers. We analyzed expression of specific mRNA and miRNA in EVs derived from ovarian cancer ascites and the ideal controls, peritoneal fluids from benign patients for potential early detection and prognostic biomarkers. METHODS: Fluids were collected from subjects with benign cysts or endometrioma (n = 10), or low/high grade serous ovarian carcinoma (n = 8). EV particles were captured using primarily ExoComplete filterplate or ultracentrifugation and analyzed by nanoparticle tracking analysis, ELISA, and scanning electron microscopy. EV RNAs extracted from two ascites and three peritoneal fluids were submitted for next-generation sequencing. The expression of 34 mRNA and 18 miRNAs in the EVs isolated from patient fluids and cell line media was determined using qPCR. RESULTS: EVs isolated from patient samples had concentrations greater than 1010 EV particles/mL and 30% were EpCAM-positive based on ELISA. EV particle sizes averaged 113 ± 11.5 nm. The qPCR studies identified five mRNA (CA11, MEDAG, LAMA4, SPINT2, NANOG) and six miRNA (let-7b, miR23b, miR29a, miR30d, miR205, miR720) that were significantly differentially expressed between cancer ascites and peritoneal fluids. In addition, CA11 mRNA was decreased to 0.5-fold and SPINT2 and NANOG mRNA were significantly increased up to 100-fold in conditioned media of cancer cells compared to immortalized ovarian surface and fallopian tube epithelial cell lines, the hypothesized cells of origin for ovarian cancer development. CONCLUSIONS: This study indicates that EV mRNA profiles can reflect the disease stage and may provide a potentially novel source for discovery of biomarkers in ovarian cancer.

Bladder cancer detection by urinary extracellular vesicle mRNA analysis.

OBJECTIVE: Urinary extracellular vesicles (EV) could be promising biomarkers for urological diseases. In this retrospective feasibility study, we conducted biomarker screening for early stage bladder cancer using EV mRNA analysis. METHODS: Biomarker candidates were identified through RNA-seq analysis of urinary EV from patients with non-muscle invasive bladder cancer (N=3), advanced urothelial cancer (N=3), no residual tumor after TURBT (N=2), and healthy and disease controls (N=4). Diagnostic performance was evaluated by RT-qPCR in a larger patient group including bladder cancer (N=173), renal pelvis and ureter cancer (N=33), no residual tumor and non-cancer disease control (N=36). RESULTS: Urinary EV SLC2A1, GPRC5A and KRT17 were overexpressed in pT1 and higher stage bladder cancer by 20.6-fold, 18.2-fold and 29.5-fold, respectively. These genes allowed detection of non-muscle invasive bladder cancer (AUC: 0.56 to 0.64 for pTa, 0.62 to 0.80 for pTis, and 0.82 to 0.86 for pT1) as well as pT2 and higher muscle invasive bladder cancer (AUC: 0.72 to 0.90). Subgroup analysis indicated that these markers could be useful for the detection of cytology-negative/-suspicious and recurrent bladder cancers. CONCLUSION: Three urinary EV mRNA were discovered to be elevated in bladder cancer. Urinary EV mRNA are promising biomarkers of urothelial cancer and worth further investigation.