Ras-like Gem GTPase induced by Npas4 promotes activity-dependent neuronal tolerance for ischemic stroke.

Ischemic stroke, which results in loss of neurological function, initiates a complex cascade of pathological events in the brain, largely driven by excitotoxic Ca2+ influx in neurons. This leads to cortical spreading depolarization, which induces expression of genes involved in both neuronal death and survival; yet, the functions of these genes remain poorly understood. Here, we profiled gene expression changes that are common to ischemia (modeled by middle cerebral artery occlusion [MCAO]) and to experience-dependent activation (modeled by exposure to an enriched environment [EE]), which also induces Ca2+ transients that trigger transcriptional programs. We found that the activity-dependent transcription factor Npas4 was up-regulated under MCAO and EE conditions and that transient activation of cortical neurons in the healthy brain by the EE decreased cell death after stroke. Furthermore, both MCAO in vivo and oxygen-glucose deprivation in vitro revealed that Npas4 is necessary and sufficient for neuroprotection. We also found that this protection involves the inhibition of L-type voltage-gated Ca2+ channels (VGCCs). Next, our systematic search for Npas4-downstream genes identified Gem, which encodes a Ras-related small GTPase that mediates neuroprotective effects of Npas4. Gem suppresses the membrane localization of L-type VGCCs to inhibit excess Ca2+ influx, thereby protecting neurons from excitotoxic death after in vitro and in vivo ischemia. Collectively, our findings indicate that Gem expression via Npas4 is necessary and sufficient to promote neuroprotection in the injured brain. Importantly, Gem is also induced in human cerebral organoids cultured under an ischemic condition, revealing Gem as a new target for drug discovery.

Impaired Hippocampal Long-Term Potentiation and Memory Deficits upon Haploinsufficiency of MDGA1 Can Be Rescued by Acute Administration of D-Cycloserine.

The maintenance of proper brain function relies heavily on the balance of excitatory and inhibitory neural circuits, governed in part by synaptic adhesion molecules. Among these, MDGA1 (MAM domain-containing glycosylphosphatidylinositol anchor 1) acts as a suppressor of synapse formation by interfering with Neuroligin-mediated interactions, crucial for maintaining the excitatory-inhibitory (E/I) balance. Mdga1-/- mice exhibit selectively enhanced inhibitory synapse formation in their hippocampal pyramidal neurons, leading to impaired hippocampal long-term potentiation (LTP) and hippocampus-dependent learning and memory function; however, it has not been fully investigated yet if the reduction in MDGA1 protein levels would alter brain function. Here, we examined the behavioral and synaptic consequences of reduced MDGA1 protein levels in Mdga1+/- mice. As observed in Mdga1-/- mice, Mdga1+/- mice exhibited significant deficits in hippocampus-dependent learning and memory tasks, such as the Morris water maze and contextual fear-conditioning tests, along with a significant deficit in the long-term potentiation (LTP) in hippocampal Schaffer collateral CA1 synapses. The acute administration of D-cycloserine, a co-agonist of NMDAR (N-methyl-d-aspartate receptor), significantly ameliorated memory impairments and restored LTP deficits specifically in Mdga1+/- mice, while having no such effect on Mdga1-/- mice. These results highlight the critical role of MDGA1 in regulating inhibitory synapse formation and maintaining the E/I balance for proper cognitive function. These findings may also suggest potential therapeutic strategies targeting the E/I imbalance to alleviate cognitive deficits associated with neuropsychiatric disorders.

Serum Sclerostin Levels and Mortality in Hemodialysis Patients: An 8-Year Prospective Study.

INTRODUCTION: Sclerostin is an osteocyte-derived inhibitor of bone formation and is increased in kidney failure. Sclerostin might be involved in the pathogenesis of vascular calcification, but few studies have examined the association between sclerostin and mortality in hemodialysis patients. METHODS: We analyzed a prospective cohort of 654 patients undergoing maintenance hemodialysis. The primary exposure variable was the baseline serum sclerostin level measured at study enrollment. The primary outcome was 8-year all-cause mortality. Mortality risk was assessed using Cox regression models adjusted for potential confounders. RESULTS: During a median follow-up of 7.6 years (interquartile range, 4.1-8.0 years), 229 of the 654 participants died. In a univariate analysis, serum sclerostin levels were not associated with mortality (HR per doubling, 0.94; 95% CI, 0.76-1.17). This result was unchanged after adjustment for age, sex, dialysis vintage, diabetes, prior cardiovascular disease, and body mass index (HR per doubling, 0.92; 95% CI, 0.72-1.17). Similar results were obtained for cardiovascular mortality. CONCLUSION: Serum sclerostin levels were not associated with mortality in maintenance hemodialysis patients. Further research is required to determine the role of sclerostin in vascular calcification and cardiovascular disease in kidney failure.

Spatial optimization of invasive species control informed by management practices.

Optimization of spatial resource allocation is crucial for the successful control of invasive species under a limited budget but requires labor-intensive surveys to estimate population parameters. In this study, we devised a novel framework for the spatially explicit optimization of capture effort allocation using state-space population models from past capture records. We applied it to a control program for invasive snapping turtles to determine effort allocation strategies that minimize the population density over the whole area. We found that spatially heterogeneous density dependence and capture pressure limit the abundance of snapping turtles. Optimal effort allocation effectively improved the control effect, but the degree of improvement varied substantially depending on the total effort. The degree of improvement by the spatial optimization of allocation effort was only 3.21% when the total effort was maintained at the 2016 level. However, when the total effort was increased by two, four, and eight times, spatial optimization resulted in improvements of 4.65%, 8.33%, and 20.35%, respectively. To achieve the management goal for snapping turtles in our study area, increasing the current total effort by more than four times was necessary, in addition to optimizing the spatial effort. The snapping turtle population is expected to reach the target density one year after the optimal management strategy is implemented, and this rapid response can be explained by high population growth rate coupled with density-dependent feedback regulation. Our results demonstrated that combining a state-space model with optimization makes it possible to adaptively improve the management of invasive species and decision-making. The method used in this study, based on removal records from an invasive management program, can be easily applied to monitoring data for wildlife and pest control management using traps in a variety of ecosystems.

Dual benefit of supplementary oral 5-aminolevulinic acid to pelvic radiotherapy in a syngenic prostate cancer model.

BACKGROUND: Normal tissue damage caused by radiotherapy remains the largest dose-limiting factor in radiotherapy for cancer. Therefore, the aim of this study was to investigate the supplementary oral 5-aminolevulinic acid (ALA) to standard radiation therapy as a novel radioprotective approach that would not compromise the antitumor effect of radiation in normal rectal and bladder mucosa in a syngenic prostate cancer (PCa) model. METHODS: To evaluate the radiosensitizing effect of ALA in vitro, clonogenic survival assays were performed in DU145, PC3, and MyC-CaP cell lines. To evaluate the effect of ALA in vivo a single dose (25 Gy) of radiation with or without ALA was given to healthy mice. Next, a syngenic PCa model of MyC-CaP cells in FVB mice was created, and multiple doses (12 Gy total) of radiation were administered to the mouse pelvic area with or without ALA administration. Resected tumors, recta, and urinary bladders were immunostained with antibodies against Ki-67, γ-H2AX, CD204, and uroplakin-III. Total RNA levels in recta and urinary bladders were analyzed via RT2 Profiler polymerase chain reaction (PCR) arrays related to "Stress & Toxicity PathwayFinder," "Mitochondria," and "Inflammasomes." RESULTS: The addition of in vitro single or in vivo repeated administration of exogenous ALA acted as a radiosensitizer for PCa cells. Rectal toxicity was characterized by histological changes including loss of surface epithelium, fibrosis, severe DNA damage, and the aggregation of M2 macrophages. Urinary bladder toxicity was characterized by bladder wall thickening and urothelium denuding. The higher dose (300 mg/kg/day) of ALA exerted a better radioprotective profile than the lower dose (30 mg/kg/day) in normal recta and urinary bladders. Out of the 252 genes tested, 35 (13.4%) were detected as relevant genes which may be involved in the radioprotective role of ALA administration. These included interleukin-1a (IL-1a), IL-1b, IL-12, chemokine (C-X-C motif) ligand 1 (CXCL1), CXCL3, and NLRP3. CONCLUSIONS: Our study provides novel and comprehensive insights into the dual benefits including radiosensitizing PCa tumor tissues and radioprotection of normal pelvic organs from radiation therapy. Knowledge of the underlying mechanism will facilitate the search for optimal treatment parameters for supplemental oral ALA during radiotherapy for PCa.

A Subtype of Olfactory Bulb Interneurons Is Required for Odor Detection and Discrimination Behaviors.

UNLABELLED: Neural circuits that undergo reorganization by newborn interneurons in the olfactory bulb (OB) are necessary for odor detection and discrimination, olfactory memory, and innate olfactory responses, including predator avoidance and sexual behaviors. The OB possesses many interneurons, including various types of granule cells (GCs); however, the contribution that each type of interneuron makes to olfactory behavioral control remains unknown. Here, we investigated the in vivo functional role of oncofetal trophoblast glycoprotein 5T4, a regulator for dendritic arborization of 5T4-expressing GCs (5T4 GCs), the level of which is reduced in the OB of 5T4 knock-out (KO) mice. Electrophysiological recordings with acute OB slices indicated that external tufted cells (ETCs) can be divided into two types, bursting and nonbursting. Optogenetic stimulation of 5T4 GCs revealed their connection to both bursting and nonbursting ETCs, as well as to mitral cells (MCs). Interestingly, nonbursting ETCs received fewer inhibitory inputs from GCs in 5T4 KO mice than from those in wild-type (WT) mice, whereas bursting ETCs and MCs received similar inputs in both mice. Furthermore, 5T4 GCs received significantly fewer excitatory inputs in 5T4 KO mice. Remarkably, in olfactory behavior tests, 5T4 KO mice had higher odor detection thresholds than the WT, as well as defects in odor discrimination learning. Therefore, the loss of 5T4 attenuates inhibitory inputs from 5T4 GCs to nonbursting ETCs and excitatory inputs to 5T4 GCs, contributing to disturbances in olfactory behavior. Our novel findings suggest that, among the various types of OB interneurons, the 5T4 GC subtype is required for odor detection and discrimination behaviors. SIGNIFICANCE STATEMENT: Neuronal circuits in the brain include glutamatergic principal neurons and GABAergic interneurons. Although the latter is a minority cell type, they are vital for normal brain function because they regulate the activity of principal neurons. If interneuron function is impaired, brain function may be damaged, leading to behavior disorder. The olfactory bulb (OB) possesses various types of interneurons, including granule cells (GCs); however, the contribution that each type of interneuron makes to the control of olfactory behavior remains unknown. Here, we analyzed electrophysiologically and behaviorally the function of oncofetal trophoblast glycoprotein 5T4, a regulator for dendritic branching in OB GCs. We found that, among the various types of OB interneuron, the 5T4 GC subtype is required for odor detection and odor discrimination behaviors.

Feasibility of photodynamic therapy for secondary hyperparathyroidism in chronic renal failure rats.

BACKGROUND: Feasibility of photodynamic therapy (PDT) for secondary hyperparathyroidism (SHPT) was examined in a rat model of SHPT. METHODS: A photosensitizer, 5-aminolevulinic acid (5-ALA), was injected intraperitoneally, and the parathyroid glands were irradiated either after surgical exposure with 385-nm light or transdermally with 630-nm light from a light-emitting diode (LED) lamp. RESULTS: PDT with high 5-ALA and irradiation doses caused severe hypoparathyroidism in SHPT rats within two days. Low-dose invasive PDT reduced intact parathyroid hormone (iPTH) levels in all rats from 748.9 ± 462.6 pg/mL at baseline to 138.7 ± 117.5 pg/mL at week 6, followed by a further decrease to 80.5 ± 54.0 pg/mL at week 9 in 60 % of rats or an increase to 970.0 ± 215.6 pg/mL at week 9 in 40 % of rats. Low-dose noninvasive PDT reduced iPTH levels from 1612.5 ± 607.8 pg/mL at baseline to 591.9 ± 480.1 pg/mL at week 4 in all rats. Thereafter, iPTH levels remained low in 43 % of rats and were 233.7 ± 51.6 pg/mL at week 9, whereas 57 % showed an increase, reaching 3305.9 ± 107.3 pg/mL at week 9. Control SHPT rats had iPTH levels of 2487.8 ± 350.9 and 2974.6 ± 372.1 pg/mL at week 4 and 9, respectively. The parathyroid glands of the rats with low iPTH levels were atrophied and had few parathyroid cells surrounded by fibrotic materials and no recognizable blood vessels. Those of the rats with high iPTH levels showed well-preserved gland structure, clusters of parathyroid cells, and blood vessels. CONCLUSION: These results demonstrate that 5-ALA-mediated PDT for SHPT is feasible.

Microsatellite Analysis of the Population Genetic Structure of Anolis carolinensis Introduced to the Ogasawara Islands.

DNA analysis can reveal the origins and dispersal patterns of invasive species. The green anole Anolis carolinensis is one such alien animal, which has been dispersed widely by humans from its native North America to many Pacific Ocean islands. In the Ogasawara (Bonin) Islands, this anole was recorded from Chichi-jima at the end of the 1960s, and then from Haha-jima in the early 1980s. These two islands are inhabited. In 2013, it was also found on the uninhabited Ani-jima, close to Chichi-jima. Humans are thought to have introduced the anole to Haha-jima, while the mode of introduction to Ani-jima is unknown. To clarify its dispersal patterns within and among these three islands, we assessed the fine-scale population genetic structure using five microsatellite loci. The results show a homogeneous genetic structure within islands, but different genetic structures among islands, suggesting that limited gene flow occurs between islands. The recently established Ani-jima population may have originated from several individuals simultaneously, or by repeated immigration from Chichi-jima. We must consider frequent incursions among these islands to control these invasive lizard populations and prevent their negative impact on native biodiversity.

Association of serum sodium levels with fractures and mortality in patients undergoing maintenance hemodialysis.

BACKGROUND: Hyponatremia is implicated in pathological bone resorption and has been identified as a risk factor for bone fracture in the general population. However, there are limited data on the association between serum sodium levels and fracture risk in patients undergoing hemodialysis (HD). METHODS: We analyzed a historical cohort of 2220 maintenance HD patients to examine the association between serum sodium levels and the risk of fracture and mortality. We also examined the association between serum sodium levels and osteoporosis, based on metacarpal bone mineral density, in a subcohort of 455 patients with available data. In addition, we examined the association between serum sodium levels and bone turnover markers in a separate cross-sectional cohort of 654 maintenance HD patients. RESULTS: During a median follow-up of 5.4 years, 712 patients died, 113 experienced clinical fractures, and 64 experienced asymptomatic vertebral fractures. Lower serum sodium levels were associated with an increased risk of mortality (HR 1.06 per 1 mEq/L decrease; 95% CI 1.03-1.09) but not with the risk of clinical fracture (HR 1.04 per 1 mEq/L decrease; 95% CI 0.97-1.11). A similar lack of association was observed for asymptomatic vertebral fracture and any fracture. Serum sodium levels were also not associated with osteoporosis in a subcohort with available data (n = 455) or with bone alkaline phosphatase or tartrate-resistant acid phosphatase-5b in a separate cross-sectional cohort. CONCLUSION: Serum sodium levels were associated with mortality but not with fracture risk, osteoporosis, or bone turnover markers in maintenance HD patients.

Suppression of the amyloidogenic metabolism of APP and the accumulation of Aß by alcadein α in the brain during aging.

Generation and accumulation of amyloid-ß (Aß) protein in the brain are the primary causes of Alzheimer's disease (AD). Alcadeins (Alcs composed of Alcα, Alcß and Alcγ family) are a neuronal membrane protein that is subject to proteolytic processing, as is Aß protein precursor (APP), by APP secretases. Previous observations suggest that Alcs are involved in the pathophysiology of Alzheimer's disease (AD). Here, we generated new mouse AppNL-F (APP-KI) lines with either Alcα- or Alcß-deficient background and analyzed APP processing and Aß accumulation through the aging process. The Alcα-deficient APP-KI (APP-KI/Alcα-KO) mice enhanced brain Aß accumulation along with increased amyloidogenic ß-site cleavage of APP through the aging process whereas Alcß-deficient APP-KI (APP-KI/Alcß-KO) mice neither affected APP metabolism nor Aß accumulation at any age. More colocalization of APP and BACE1 was observed in the endolysosomal pathway in neurons of APP-KI/Alcα-KO mice compared to APP-KI and APP-KI/Alcß-KO mice. These results indicate that Alcα plays an important role in the neuroprotective function by suppressing the amyloidogenic cleavage of APP by BACE1 in the brain, which is distinct from the neuroprotective function of Alcß, in which p3-Alcß peptides derived from Alcß restores the viability in neurons impaired by toxic Aß.

5T4 glycoprotein regulates the sensory input-dependent development of a specific subtype of newborn interneurons in the mouse olfactory bulb.

Sensory input has been shown to regulate development in a variety of species and in various structures, including the retina, cortex, and olfactory bulb (OB). Within the mammalian OB specifically, the development of dendrites in mitral/tufted cells is well known to be odor-evoked activity dependent. However, little is known about the developmental role of sensory input in the other major OB population of the GABAgenic interneurons, such as granule cells and periglomerular cells. Here, we identified, with DNA microarray and in situ hybridization screenings, a trophoblast glycoprotein gene, 5T4, whose expression in a specific subtype of OB interneurons is dependent on sensory input. 5T4 is a type I membrane protein, whose extracellular domain contains seven leucine-rich repeats (LRR) flanked by characteristic LRR-N-flanking and C-flanking regions, and a cytoplasmic domain. 5T4 overexpression in the newborn OB interneurons facilitated their dendritic arborization even under the sensory input-deprived condition. By contrast, both 5T4 knockdown with RNAi and 5T4 knockout with mice resulted in a significant reduction in the dendritic arborization of 5T4(+) granule cells. Further, we identified the amino acid sequence in the 5T4 cytoplasmic domain that is necessary and sufficient for the sensory input-dependent dendritic shaping of specific neuronal subtypes in the OB. Thus, these results demonstrate that 5T4 glycoprotein contributes in the regulation of activity-dependent dendritic development of interneurons and the formation of functional neural circuitry in the OB.

Evaluation of bioartificial renal tubule device prepared with human renal proximal tubular epithelial cells cultured in serum-free medium.

Bioartificial renal tubule devices (BTD) use cell therapy to improve conditions commonly observed in recipients of artificial kidneys for treatment of kidney diseases. We previously reported significant improvement of the condition of acute kidney injury (AKI) animals after treatment with BTD prepared with lifespan-extended human renal proximal tubular cells (hRPTEC). However, a major obstacle to use of BTD for patients is their biological safety, because hRPTEC are cultured in medium containing fetal calf serum. To establish the biological safety of BTD, we prepared BTD with lifespan-extended hRPTEC cultured in a newly developed serum-free medium and compared these with BTD prepared with hRPTEC cultured in serum-containing conventional medium. Lifespan-extended hRPTEC cultured in serum-free medium (hRPTEC-SFM) can proliferate similar to hRPTEC cultured in serum-containing conventional medium (hRPTEC-CM). Comparison of leakage and of reabsorption of small molecules for BTD prepared with hRPTEC-SFM (BTD-SFM) with those for our previous BTD prepared with hRPTEC-CM (BTD-CM) showed transportation in these two types of BTD was almost identical. When AKI goats were treated with BTD-SFM for 26 h, increase of survival time and reduction of cytokine expression in blood cells were almost same as for AKI goats treated with BTD-CM. Quantification of the expression of some genes of hRPTEC in BTD revealed significant changes during BTD treatment for AKI goats. In conclusion, lifespan-extended hRPTEC-SFM work as well as hRPTEC-CM, and the biological safety of BTD for patients could be elevated without loss of function by preparation from hRPTEC-SFM.

Molecular mechanisms underlying activity-dependent ischemic tolerance in the brain.

Ischemic stroke is one of the leading causes of death and disability worldwide. The inhibition of cerebral blood flow triggers intertwined pathological events, resulting in cell death and loss of brain function. Interestingly, animals pre-exposed to short-term ischemia can tolerate subsequent severe ischemia. This phenomenon is called ischemic tolerance and is also triggered by other noxious stimuli. However, whether short-term exposure to non-noxious stimuli can induce ischemic tolerance remains unknown. Recently, we found that pre-exposing mice to an enriched environment for 40 min is sufficient to facilitate cell survival after a subsequent stroke. The neuroprotective process depends on the neuronal activity soon before stroke, of which the activity-dependent transcription factor Npas4 is essential. Excessive Ca2+ influx triggers Npas4 expression in ischemic neurons, leading to the activation of neuroprotective programs. Pre-induction of Npas4 in the normal brain effectively supports cell survival after stroke. Furthermore, our study revealed that Npas4 regulates L-type voltage-gated Ca2+ channels through expression of the small Ras-like GTPase Gem in ischemic neurons. Ischemic tolerance is a good model for understanding how to promote neuroprotective mechanisms in the normal and injured brain. Here, we highlight activity-dependent ischemic tolerance and discuss its role in promoting neuroprotection against stroke.

Usefulness of a Novel Vascular Access Management Method Using a Laser Blood Flowmeter.

INTRODUCTION: Various methods for vascular access (VA) management have been studied. We investigated the usefulness of a new, simple, and quantitative VA management method using the Pocket LDF® laser blood flowmeter (hereinafter "LDF") that noninvasively measures peripheral circulation flow. METHODS: Peripheral circulation flow was measured in 82 patients (43 men) on maintenance hemodialysis with an arteriovenous fistula (AVF). The shunt symmetry index (SSI) was calculated as peripheral circulation flow in the AVF limb divided by that in the non-AVF limb. SSI was used for microcirculation evaluation and also compared by AVF site. Patients undergoing vascular access interventional therapy (VAIVT) underwent ultrasound evaluation (Doppler ultrasonography) of the AVF and SSI measurement before and after VAIVT. SSI was compared between those who did and did not require VAIVT, and the cutoff value for SSI was determined by receiver operating characteristic curve (ROC) analysis. RESULTS: As many as 86% of the patients who were measured peripheral circulation flow had SSI <1.0, which indicates that AVF reduced peripheral circulation flow. All patients who underwent VAIVT showed a decrease in SSI to <1.0 after VAIVT, probably due to improvement of stenosis. SSI differed significantly between patients who did and did not require VAIVT (1.20 ± 0.49 vs. 0.65 ± 0.33, p < 0.001), which indicates that SSI is affected by the presence of stenosis in the proximal vein of the VA anastomosis. In patients with SSI ≥1.0, stenosis of the proximal vein of the AVF caused stasis of blood flow, resulting in increased peripheral blood flow. AVF site seems to have no impact on peripheral circulation flow. The SSI cutoff value for the screening of proximal vein stenosis was 1.06 (sensitivity: 0.69, specificity: 0.93, area under the curve: 0.81). CONCLUSION: Based on the ROC analysis, we recommend considering AVF ultrasound for SSI >1.06. Our results suggest the usefulness of the described VA management method using the LDF.

Record of Cryptosporidium serpentis from Goniurosaurus kuroiwae sengokui (Reptilia, Squamata, Eublepharidae) in Tokashikijima, Okinawa Prefecture, Japan.

In reptiles, infection with Cryptosporidium parasite can be lethal, especially in species of family Eublepharidae such as Eublepharis macularius and Goniurosaurus splendes species. We investigated the presence of Cryptosporidium spp. in wild reptiles, especially Goniurosaurus spp., in five islands of Japan. Nested PCR was performed to detect Cryptosporidium spp. in 38 fecal samples of 9 reptile species from five islands of Japan, and 3 (3/8) positive samples of Goniurosaurus kuroiwae sengokui from Tokashikijima, Okinawa Prefecture were detected. A BLAST search of the detected gene sequences revealed that the all 3 samples were identified as Cryptosporidium serpentis, a reptile-specific Cryptosporidium parasite. This is the first record of Cryptosporidium from a wild Goniurosaurus species in Japan and worldwide.

Evaluation of ABCG2-mediated extra-renal urate excretion in hemodialysis patients.

Two-thirds of urate is excreted via the renal pathway and the remaining one-third via the extra-renal pathway, the latter mainly via the intestine in healthy individuals. ABCG2, a urate exporter, is expressed in various tissues including the kidney and intestine, and its dysfunction leads to hyperuricemia and gout. ABCG2 is regarded as being responsible for most of the extra-renal urate excretion. However, the extra-renal urate excretion capacity via ABCG2 remains undefined in end-stage kidney diseases. Therefore, we evaluated the capacity of extra-renal ABCG2 using 123 anuric hemodialysis patients whose urate excretion depended on only the extra-renal pathway. ABCG2 function in each participant was estimated based on ABCG2 dysfunctional variants. We computed the uric acid pool (PoolUA) from bodyweight and serum urate level (SUA) using previously reported radio-isotopic data, and we analyzed the association between ABCG2 function and the PoolUA. SUA and PoolUA increased significantly with ABCG2 dysfunction, and extra-renal ABCG2 could excrete up to approximately 60% of the daily uric acid turnover in hemodialysis patients. Our findings indicate that the extra-renal urate excretion capacity can expand with renal function decline and highlight that the extra-renal pathway is particularly important in the uric acid homeostasis for patients with renal dysfunction.

Effects of cinacalcet treatment on serum soluble Klotho levels in haemodialysis patients with secondary hyperparathyroidism.

BACKGROUND: Klotho is a transmembrane protein that acts as a cofactor for fibroblast growth factor 23 (FGF23). Klotho also exists as a soluble circulating protein, but its role in secondary hyperparathyroidism (SHPT) is largely unknown. METHODS: We measured serum soluble Klotho levels in 51 haemodialysis patients, who participated and completed a 52-week, multicentre, open-label single-arm trial that examined the effectiveness of cinacalcet for treating SHPT. RESULTS: After 12 weeks of cinacalcet treatment, serum soluble Klotho decreased significantly (P = 0.03) but only marginally from 398 pg/mL [interquartile range (IQR), 268-588 pg/mL] to 378 pg/mL (IQR, 266-568 pg/mL) and returned to baseline levels. There were no significant associations between the changes in soluble Klotho levels and changes in any other parameters of mineral metabolism, including serum calcium, phosphorus, intact parathyroid hormone and FGF23. CONCLUSION: Despite significant alterations in mineral and bone metabolism during treatment with cinacalcet, this resulted in only small and transient reductions in serum levels of soluble Klotho.

Evaluation of bioartificial renal tubule device prepared with lifespan-extended human renal proximal tubular epithelial cells.

BACKGROUND: Acute kidney injury (AKI), accompanied by the development of systemic inflammatory response syndrome and multiorgan dysfunction syndrome, is associated with a high risk of death. Bioartificial renal tubule device (BTD) is a cell therapy that improves the conditions common to artificial kidney recipients treated for kidney diseases. In this paper, we describe the establishment of BTD with lifespan-extended human renal proximal tubular epithelial cells. METHODS: AKI goats were established by performing bilateral nephrectomy followed by lipopolysaccharide administration. The AKI goats were treated with BTD or sham-BTD, and the two groups of animals were compared by measuring the respective life spans and the levels of blood urea nitrogen, creatinine, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and serum electrolytes. The expression levels of inflammatory cytokines were detected by reverse transcription-polymerase chain reaction, and plasma interleukin (IL)-6 levels were measured by enzyme-linked immunosorbent assay. RESULTS: The life span of AKI goats was extended: the lifetime with the BTD treatment compared with sham-BTD. BTD and sham-BTD showed a similar degree of small solute clearance. The expression levels of inflammatory cytokines and plasma IL-6 levels were decreased by the BTD treatment. CONCLUSIONS: BTD treatment results in less damage from endotoxin shock and increased life span in AKI goats. These results suggest that BTD may be a useful component of bioartificial kidneys and should be considered in the next generation of renal replacement therapies.

Prediction of Service Performance Based on Physical Strength in Elite Junior Tennis Players.

In tennis, service requires a variety of complicated movements. Given the importance of taking the initiative to obtain points in a tennis match, it is crucial to make full use of speed and spin rate of service. Generally, a service that requires a higher spin rate would slow down, and a service that has increased speed would have a decreased spin rate. For players who are disadvantaged in height, although controlling spin rate is essential, slowing down service speed should be avoided. For these players, the challenge of service is to improve the speed without decreasing the spin rate. Players must also be trained to build physical strength required for this skill. It is not uncommon to work on physical training without a racket; however, few studies have reported on the effects of cultivated physical strength on on-court tennis performance. Therefore, this study aimed to propose physical measurements that could be used as indices to improve service performance in 58 elite Japanese junior male players. To test service performance, we used TrackMan tennis radar device to assess speed, spin rate, impact height, and impact depth. To test physical strength, we measured 5- and 20-m sprint, broad jump, medicine ball throw (forward, backward). We used a significant multiple regression equation to predict the first service speed obtained from the broad jump and the Medicine ball throw (backward). Additionally, a strong correlation was obtained between the predicted and measured values. In addition to physical strength, we suggest that the depth of the impact point (taking the hitting point forward toward the net) is important for improving the first service speed. However, we were not able to identify the physical strength test items that improve service spin rate. Other item should be examined in the future to determine the physical strength associated with spin rate. This result could help connect physical training and service performance.

Formation of N-acyl-phosphatidylethanolamines by cytosolic phospholipase A2ε in an ex vivo murine model of brain ischemia.

N-Acyl-phosphatidylethanolamines (NAPEs), a minor class of membrane glycerophospholipids, accumulate along with their bioactive metabolites, N-acylethanolamines (NAEs) during ischemia. NAPEs can be formed through N-acylation of phosphatidylethanolamine by cytosolic phospholipase A2ε (cPLA2ε, also known as PLA2G4E) or members of the phospholipase A and acyltransferase (PLAAT) family. However, the enzyme responsible for the NAPE production in brain ischemia has not yet been clarified. Here, we investigated a possible role of cPLA2ε using cPLA2ε-deficient (Pla2g4e-/-) mice. As analyzed with brain homogenates of wild-type mice, the age dependency of Ca2+-dependent NAPE-forming activity showed a bell-shape pattern being the highest at the first week of postnatal life, and the activity was completely abolished in Pla2g4e-/- mice. However, liquid chromatography-tandem mass spectrometry revealed that the NAPE levels of normal brain were similar between wild-type and Pla2g4e-/- mice. In contrast, post-mortal accumulations of NAPEs and most species of NAEs were only observed in decapitated brains of wild-type mice. These results suggested that cPLA2ε is responsible for Ca2+-dependent formation of NAPEs in the brain as well as the accumulation of NAPEs and NAEs during ischemia, while other enzyme(s) appeared to be involved in the maintenance of basal NAPE levels.