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The amount of chitin, a nitrogen-containing dietary fiber, in edible insects can mislead the exact nitrogen-to-protein conversion factor (NPF) and true protein content. We determined the amino acid score (AAS), protein digestibility-corrected AAS (PDCAAS), chitin content, and net NPF of five edible insects. Additionally, the effect of the amino acid composition of migratory locust on rat growth were investigated. The AAS of the insects were ranged from 63 to 94. The chitin contents were ranged from 1.6 g/100 g to 10.7 g/100 g. The PDCAAS, calculated by AAS and gut-intestinal digestibility, ranged from 44 to 81, which was lower than casein (97). The net NPF ranged from 4.93 to 5.76, which were lower than the conventional value. Dietary migratory locust, whose PDCAAS was the lowest, decreased growth and altered lipid metabolism. Therefore, a lower PDCAAS and overestimation of net NPF of insects can affect the true protein calculations and growth. [Display omitted] • Chitin content in dried insects ranges from 1.6 g/100 g to 10.7 g/100 g. • Net nitrogen-protein conversion factor of insect proteins ranges from 4.93 to 5.76. • Gut-intestinal digestibility of insect proteins ranges from 70% to 86%. • Protein digestibility-corrected amino acid score of insects ranges from 44 to 81. • Edible migratory locust protein in diet decreases growth in young rats. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants could discharge Escherichia coli and antibiotic resistant bacteria to the environment adjacent to, or downstream of their discharge point. However, their discharge also contains nutrients which could promote growth of E. coli in water environments. This study was done to clarify the potential of growth and antibiotic resistance acquisition of E. coli in a river environment. Levels of E. coli were monitored in a river that receives treated sewage effluent for over four years. River water, periphyton and sediment samples were collected at sites upstream and downstream of treated sewage inflow. Concentrations of E. coli increased in river water and periphyton at the sites downstream of the treated sewage inflow, although levels of E. coli were very low or below detection limit in the treated sewage samples. Concentrations of Chlorophyll a increased at the downstream sites, likely due to nutrient input from the treated sewage. Based on pulsed field gel electrophoresis, identical genotype occurred at multiple sites both upstream and downstream of the treated sewage inflow. However, strains resistant to antibiotics such as ampicillin, cefazolin, ciprofloxacin, and chloramphenicol were more frequently obtained from the downstream sites than the upstream sites. Multidrug resistant E. coli strains were detected in periphyton and sediment samples collected at the downstream sites. Non-resistant strains with PDGE genotype identical to the multi-drug strains were also detected, indicating that E. coli might have become resistant to antibiotics by acquiring resistance genes via horizontal gene transfer. Laboratory incubation experiment showed the growth of E. coli in periphyton or sediment-fed river water samples. These results suggest that the wastewater treatment inflow did not directly provide E. coli to the river water, but could promote the growth of periphyton, which could lead to the elevated levels of E. coli and the emergence of antibiotic resistant E. coli. Unlabelled Image • E. coli grows and acquire the antibiotic resistance in a river environment. • Inorganic nutrients in treated sewage likely promoted the growth of periphyton, in which E. coli can grow. • E. coli grew in river water when sterilized periphyton or sediment was supplemented. • Periphyton could serve as a hot spot for bacteria to obtain antibiotic resistance genes. • Environment-borne E. coli in the periphyton on riverbed rocks can be released to river water. [ABSTRACT FROM AUTHOR]

To determine the effects of bacteria pollution associated with a strong typhoon event and to assess the restoration of the normal bacterial flora, we used conventional filtration methods and nextgeneration sequencing of 16S rRNA genes to analyze the transition of fecal and total bacterial counts in water and core sand samples collected from a recreational beach. Immediately after the typhoon event, Escherichia coli counts increased to 82 CFU/100 g in the surface beach sand. E. coli was detected through the surface to sand 85-cm deep at the land side point (10-m land side from the high-water line). However, E. coli disappeared within a month from the land side point. The composition of the bacterial flora in the beach sand at the land point was directly influenced by the typhoon event. Pseudomonas was the most prevalent genus throughout the sand layers (0–102-cm deep) during the typhoon event. After 3 months, the population of Pseudomonas significantly decreased, and the predominant genus in the surface layer was Kaistobacter, although Pseudomonas was the major genus in the 17- to 85-cm layer. When the beach conditions stabilized, the number of pollutant Pseudomonas among the 10 most abundant genera decreased to lower than the limit of detection. The bacterial population of the sand was subsequently restored to the most populous pre-event orders at the land point. A land-side beach, where users directly contact the sand, was significantly affected by bacterial pollution caused by a strong typhoon event. We show here that the normal bacterial flora of the surface sand was restored within 1 month. [ABSTRACT FROM AUTHOR]

The central role of neuropeptide S (NPS), identified as the endogenous ligand for GPR154, now named neuropeptide S receptor (NPSR), has not yet been fully clarified. We examined the central role of NPS for body temperature, energy expenditure, locomotor activity and adrenal hormone secretion in rats. Intracerebroventricular (icv) injection of NPS increased body temperature in a dose-dependent manner. Energy consumption and locomotor activity were also significantly increased by icv injection of NPS. In addition, icv injection of NPS increased the peripheral blood concentration of adrenalin and corticosterone. Pretreatment with the β1- and β2-adrenergic receptor blocker timolol inhibited the NPS-induced increase of body temperature. The expression of both NPS mRNA in the brainstem and NPSR mRNA in the hypothalamus showed a nocturnal rhythm with a peak occurring during the first half of the dark period. To examine whether the endogenous NPS is involved in regulation of body temperature, NPSR antagonist SHA68 was administered one hour after darkness. SHA68 attenuated the nocturnal rise of body temperature. These results suggest that NPS contributes to the regulation of the sympathetic nervous system. [ABSTRACT FROM AUTHOR]

Vertical "half-and-half" syndrome, characterized by contralateral upward and ipsilateral downward gaze palsy, is a rare variant of vertical eye movement disturbance. Similarly, pseudoabducens palsy, manifesting as abductive palsy despite no lesion to the pons, constitutes another rare type of eye movement disturbance. Both conditions have been associated with lesions in the thalamo-mesencephalic junction. We present a rare case report detailing a patient exhibiting vertical "half-and-half" syndrome with ipsilateral pseudoabducens palsy following a left lacunar infarction of the thalamo-mesencephalic junction. Additionally, we discuss the potential underlying mechanisms contributing to this rare combination of eye movement disorders. [ABSTRACT FROM AUTHOR]

On a livestock farm where antimicrobial administration and its history had been managed for prudent use of antimicrobials, we surveyed antibiotic-resistant Escherichia coli strains isolated from cow feces and the surrounding environment (i.e., rat and crow feces, and water samples from a drainage pit and wastewater processing tank) every month for 1 year. Two strains (1.7%) in cow feces were resistant to tetracycline, whereas all other strains were susceptible to all other antimicrobials. Among 136 strains isolated from cows and wild animals, only one ampicillin-resistant strain was identified. The antibiotic resistance rate in the drainage from the barn was 8.3% (10/120), and all strains showed susceptibility for 8 months of the year. Tetracycline resistance was common in all resistant strains isolated from animal feces and water samples; all tetracycline-resistant strains carried tetA. These results strongly support the proper use and management of antibiotics on farms to minimize the outbreak and spread of antibiotic-resistant bacteria. [ABSTRACT FROM AUTHOR]

Abstract: Pseudomonas aeruginosa is responsible for a number of opportunistic and nosocomial infections. However, very little information is available on the ecology of P. aeruginosa in water environments and its association with antimicrobial resistance. In this study, the distribution of P. aeruginosa and the resistance of P. aeruginosa isolates to various antibiotics were investigated from two rivers, Kiyotake and Yae that flow through Miyazaki City, Japan. P. aeruginosa was distributed widely along the river basins with counts ranging from 2–46cfu/100mL. The susceptibility of P. aeruginosa isolates collected from the rivers to various antibiotics was examined by minimum inhibitory concentration. Multidrug-resistant P. aeruginosa strains were not observed or isolated from either river. However, one piperacillin-resistant P. aeruginosa was detected among a total of 516 isolates, and this isolate was also resistant to cefotaxime and showed intermediate resistance to cefitazidime. Less than 1% of all isolates (n=5) were resistant to imipenem, which is the most effective antibiotic against both Gram-negative and Gram-positive bacteria. However, all P. aeruginosa isolates were completely resistant to tetracyclines, which are the most commonly prescribed antibiotics. In advanced nations such as Japan where the majority of the population is urban and where medical services are widespread, antibiotic-resistant bacteria such as P. aeruginosa are likely to be widely distributed, even in apparently pristine rivers. [Copyright &y& Elsevier]

Abstract: The green tea polyphenol (−)-epigallocatechin-3-O-gallate (EGCG) has various biological activities, including anti-inflammatory, anti-neoplastic, anti- and pro-apoptotic, and neuroprotective effects. Although these are often associated with increased intracellular reactive oxygen species (ROS) and Ca2+ levels, their involvement in biological effects is poorly understood. Here we report that EGCG induces cytokine production in mast cells via Ca2+ influx and ROS generation. EGCG at concentrations of ≥50μM induced interleukin-13 and tumor necrosis factor-α production in RBL-2H3 and bone marrow-derived mast cells. The effects were dependent on extracellular Ca2+, and EGCG induced Ca2+ release from intracellular stores and Ca2+ influx. Ca2+ influx was suppressed by 2-aminoethoxydiphenyl borate, an inhibitor of store-operated Ca2+ (SOC) channels, including Ca2+ release-activated Ca2+ channels and transient receptor potential canonical channels. EGCG failed to induce Ca2+ influx through SOC channels. EGCG-activated Ca2+ channels were genetically and pharmacologically distinct from Cav1.2 L-type Ca2+ channels, another route of Ca2+ influx into mast cells. EGCG evoked release of superoxide (O2 −) into the extracellular space. Exogenous superoxide dismutase, but not catalase, inhibited EGCG-evoked Ca2+ influx and cytokine production, indicating that extracellular O2 − regulates these events. EGCG can serve as a powerful tool for studying O2 −-regulated Ca2+ channels, which may be selectively involved in the regulation of cytokine production but have yet to be elucidated. [Copyright &y& Elsevier]

Abstract: The monitoring of NVs in municipal wastewater by both real-time RT-LAMP and real-time RT-PCR, and the comparison of these two methods with respect to NV detection were carried out. The change in NVs detected by real-time RT-LAMP agreed well with that detected by real-time RT-PCR. In contrast, the correlation between the copy number determined by real-time RT-PCR and the threshold time (Tt) determined by real-time RT-LAMP obtained during monitoring was not significant (0.1

Abstract: Heavy metals, including gold, induce severe contact hypersensitivity and autoimmune disorders, which develop through an initial Th2-independent process followed by a Th2-dependent process. It has been shown that mast cell activation plays a role in the Th2-independent process and that gold stimulates histamine release in vitro. However, the mechanisms of the gold-induced mast cell activation remain largely unclear. Here we report that gold directly activates mast cells in a Ca2+-dependent manner. HAuCl4 [Au(III)] at nontoxic concentrations (≤50μM) induced substantial degranulation and leukotriene C4 secretion in an extracellular Ca2+-dependent manner. Au(III) induced a robust Ca2+ influx but not Ca2+ mobilization from internal stores. Au(III) also stimulated intracellular production of reactive oxygen species, including H2O2, and blockade of the production abolished the mediator release and Ca2+ influx. Au(III) induced Ca2+ influx through multiple store-independent Ca2+ channels, including Cav1.2 L-type Ca2+ channels (LTCCs) and 2-aminoethoxydiphenyl borate (2-APB)-sensitive Ca2+ channels. The 2-APB-sensitive channel seemed to mediate Au(III)-induced degranulation. Our results indicate that gold stimulates Ca2+ influx and mediator release in mast cells through multiple H2O2-sensitive Ca2+ channels including LTCCs and 2-APB-sensitive Ca2+ channels. These findings provide insight into the roles of these Ca2+ channels in the Th2-independent process of gold-induced immunological disorders. [Copyright &y& Elsevier]

Abstract: SHP-1 plays an important role for the regulation of signaling from various hematopoietic cell receptors. In this study, we examined IL-3-induced cell proliferation and IL-3 depletion-induced apoptosis in bone marrow-derived mast cells (BMMC) established from motheaten (me) that lack SHP-1 expression, viable motheaten (me v ) expressing phosphatase-deficient SHP-1, and wild-type (WT) mice. When BMMC were stimulated with IL-3, increased ERK activation was evident in resting state and sustained in me-BMMC relative to WT-BMMC. ERK is known to be involved in the regulation of cell proliferation and apoptosis in some cells. In accordance with sustained ERK activation, apoptosis was decreased in me- and me v -BMMC compared with WT-BMMC. In contrast to the predicted role of ERK as a pro-survival molecule, IL-3-induced cell proliferation was much lower in me- and me v -BMMC than WT-BMMC. Stimulation with lower concentration of IL-3 or addition of PD98059, a MEK inhibitor, to the culture resulted in the suppression of decreased apoptosis and cell proliferation in me- and me v -BMMC. Collectively, these results suggest that SHP-1 positively regulates IL-3-dependent mast cell proliferation and apoptosis by inhibiting ERK activity through its phosphatase activity. Furthermore, our results indicate that ERK would act as a negative regulator for cell proliferation and induce apoptosis when its activity is highly increased. [ABSTRACT FROM AUTHOR]

Abstract: The green tea polyphenol (–)-epigallocatechin-3-O-gallate (EGCG) has been shown to reduce allergic inflammatory responses in animal models, but the mechanisms involved are poorly understood. Despite the essential role for Ca2+ influx in mediating proinflammatory mediator release from mast cells, little is known about the effects of EGCG on this response. In the present study we found that EGCG inhibited antigen-induced Ca2+ influx and store-operated Ca2+ entry (SOCE), the principal mode of Ca2+ influx into mast cells. EGCG, but not (–)-epicatechin (EC), inhibited antigen-induced degranulation, leukotriene (LT) C4 secretion, and Ca2+ influx. EGCG also blocked SOCE without reducing Ca2+ store emptying whereas EC did not, although it did reduce Ca2+ store emptying. EGCG, but not EC, also evoked intracellular reactive oxygen species (ROS) production, mitochondrial membrane potential (∆Ψm) collapse, cardiolipin oxidation, and mitochondrial Ca2+ ([Ca2+]m) release. Furthermore, FCCP, a potent inducer of ∆Ψm collapse, induced ROS production and [Ca2+]m dysfunction and inhibited degranulation, LTC4 secretion, Ca2+ influx, and SOCE. These data suggest that ROS production and ∆Ψm collapse are important mechanisms underlying the antiallergic effects of EGCG. These events may lead to [Ca2+]m dysfunction and impair mitochondria-mediated facilitation of SOCE, thereby attenuating mast cell activation. [Copyright &y& Elsevier]

Abstract: Recent pharmacological and molecular genetic approaches have revealed the existence of functional L-type Ca2+ channels (LTCCs) in a variety of hematopoietic cells. We previously reported that Cav1.2 LTCCs are expressed on mast cell surfaces, activated by the high-affinity IgE receptor (FcɛRI) engagement and protect mast cells against activation-induced cell death (AICD). We also demonstrated that FcɛRI engagement evokes nitric oxide (NO) generation in a phosphatidylinositol-3-kinase- and NO synthase (NOS)-dependent manner, which is also required for mast cell survival. Here we demonstrate that this endogenous NO mediates Cav1.2 LTCC activation. FcɛRI engagement but not thapsigargin, a potent Ca2+ release-activated Ca2+ (CRAC) channel agonist, induced Ca2+ influx via NOS-dependent NO generation. RT-PCR analyses revealed predominant expression of eNOS in mast cells. Subsequent experiments involving siRNA-mediated gene silencing of eNOS or Cav1.2 LTCC revealed that eNOS was essential for NOS-dependent NO generation and Cav1.2 LTCC activation but not CRAC channel activation. Similar to Cav1.2 LTCCs, eNOS prevented the dissipation of the mitochondrial membrane potential and mitochondrial integrity collapse, thereby protecting mast cells against AICD. Taken together, the present findings demonstrate the key roles of the eNOS-NO-LTCC axis in mast cell survival after FcɛRI engagement. [Copyright &y& Elsevier]

Abstract: Ca2+ is a highly versatile intracellular second messenger in many cell types, and regulates many complicated cellular processes, including cell activation, proliferation and apoptosis. Influx of Ca2+ from the extracellular fluid is required for sustained elevation of the cytosolic Ca2+ concentration and full activation of Ca2+-dependent processes. It is widely accepted that Ca2+ release-activated Ca2+ channels are the major routes of Ca2+ influx in electrically non-excitable cells, including hematopoietic cells, whereas voltage-gated Ca2+ channels such as L-type Ca2+ channels (LTCCs) serve as the principal routes of Ca2+ entry into electrically excitable cells such as neurons and myocytes. However, recent pharmacological and molecular genetic studies have revealed the existence of functional LTCCs and/or LTCC-like channels in a variety of immune cells including mast cells. In this article, we review recent advances in our understanding of Ca2+ signaling in immune cells with a special interest in mast cells. We highlight roles for LTCCs in antigen receptor-mediated mast cell activation and survival. [Copyright &y& Elsevier]

Abstract: Src homology region 2 domain-containing phosphatase-1 (SHP-1) is known to act as a negative signal modulator in mast cells but its roles in cell survival and cell death are poorly understood. We previously reported that SHP-1 also positively regulates mast cell activation signaling by acting as an adaptor protein. In the present study, we examined whether SHP-1 plays a role in antigen (Ag)-induced activation-induced mast cell death. Bone marrow-derived mast cells (BMMCs) from SHP-1-deficient motheaten (me) mice (me-BMMCs) were significantly less susceptible to store-operated Ca2+ channel (SOC) activation, Ag-induced cell death and DNA fragmentation than BMMCs from their wild-type littermates (WT-BMMCs). Subsequent experiments revealed that the differences in these cellular susceptibilities to SOC activation and cell death resulted from the extent of the mitochondrial permeability transition pore (mPTP) opening. Specifically, mPTP opening was sufficiently persistent in WT-BMMCs to evoke mitochondrial integrity disruption, while mPTP opening was too transient to cause the minimal mitochondrial integrity collapse in me-BMMCs. In addition, pro-survival signaling including activation of mitogen-activated protein kinases (MAPKs) such as the extracellular signal-regulated protein kinases, c-Jun NH2 terminal kinases and p38 and the expression of Bcl-xL were significantly prolonged in me-BMMCs compared with WT-BMMCs. Taken together, these data demonstrate that a lack of SHP-1 prevents the mPTP-mediated mitochondrial integrity collapse and augments anti-apoptotic signaling such as MAPKs and Bcl-xL. These findings suggest that SHP-1 positively regulates mitochondrial death pathways and negatively regulates pro-survival signaling pathways. [Copyright &y& Elsevier]

Abstract: In non-excitable cells, store-operated Ca2+ channels (SOCs) are the principal routes of Ca2+ entry. Recently, store-independent Ca2+ channels which are pharmacologically and/or immunologically similar to L-type Ca2+ channels (LTCCs) have been shown to exist in various hematopoietic cells, including T cells, B cells and neutrophils. We previously reported that mast cells express LTCCs which regulate mast cell effector responses in a distinct manner from SOCs. In the present study, we examined the possible role for LTCCs in mast cell survival. Both RBL-2H3 mast cells and bone marrow-derived mast cells underwent considerable apoptosis after treatment with thapsigargin (Tg) but not stimulation through the high-affinity IgE receptor (FcɛRI). The LTCC-selective antagonists such as nifedipine greatly augmented FcɛRI-mediated apoptosis, while the LTCC-selective agonist (S)-BayK8644 blocked Tg-induced apoptosis. The modulation of apoptosis was accompanied by altered mitochondrial integrity, as measured with the mitochondrial membrane potential, cytochrome c release and caspase-3/7 activation. FcɛRI stimulation induced mitochondrial Ca2+ ([Ca2+]m) entry through both SOCs and LTCCs, while Tg evoked [Ca2+]m entry through LTCCs but not SOCs. The LTCC-selective antagonists blocked [Ca2+]m entry, whereas (S)-BayK8644 augmented Tg-induced [Ca2+]m entry. Moreover, blockade of the expression of the α1C subunit of Cav1.2 LTCC using small-interfering RNA strongly augmented FcɛRI-mediated apoptosis, mitochondrial integrity, and mitochondrial Ca2+ collapse, and abolished the protective effects of (S)-BayK8644 against Tg-induced apoptosis. These findings suggest that Cav1.2 LTCC protects mast cells against activation-induced cell death by preventing mitochondrial integrity disruption. [Copyright &y& Elsevier]

Abstract: Mast cells and T cells produce reactive oxygen species (ROS) after stimulation with the high-affinity IgE receptor (FcɛRI) and T cell receptor. A growing body of evidence suggests the existence of ROS-regulated intracellular and/or plasma membrane Ca2+ channels in these cells but their molecular entities remain to be identified. Here, we report that store-operated Ca2+ channel (SOC) activity is regulated by superoxide (O2 •−) and hydrogen peroxide (H2O2) in mast cells. MnTBaP (Mn(III)tetrakis(4-benzoic acid)porphyrin) and ebselen (2-phenyl-1,2-benziso-selenazol-3(2H)-one) selectively blocked the generation of O2 •− and H2O2, respectively, in antigen-stimulated cells. The H2O2 generation was dependent on the Src family kinase (SFK) and phosphatidylinositol-3-kinase (PI3K) activities but independent of extracellular Ca2+, and the FcɛRI β-chain immunoreceptor tyrosine-based activation motif played an essential role. On the other hand, O2 •− generation was strictly dependent on extracellular Ca2+, but negatively regulated by the SFK and PI3K activities. Inhibition of O2 •− generation resulted in increased H2O2 generation and reduced SOC activity, although it had a minimal effect on endoplasmic reticulum Ca2+ store depletion. On the contrary, inhibition of H2O2 generation resulted in increased intracellular O2 •− generation and augmented SOC activity. The findings suggest that O2 •− and H2O2, which are generated by separate signaling pathways/sources, reciprocally regulate SOC activity in mast cells. Such generations of multiple oxidant species and their distinct roles in the regulation of SOC activity may facilitate the fine tuning of Ca2+ signaling in mast cells. [Copyright &y& Elsevier]

Abstract: Store-operated Ca2+ channels (SOCs) are considered to be the principal route of Ca2+ influx in non-excitable cells. We have previously shown that in mast cells IgE+antigen (Ag) induces a dihydropyridine (DHP)-sensitive Ca2+ influx independently of Ca2+ store depletion. Since the DHP receptor is the α subunit of L-type Ca2+ channels (LTCCs), we examined the possible role of LTCCs in mast cell activation. Mast cells exhibited substantial expression of the α1C (CaV1.2) subunit mRNA and protein on their cell surface. IgE+Ag-induced Ca2+ influx was substantially reduced by the LTCC inhibitor nifedipine, and enhanced by the LTCC activator (S)-BayK8644, whereas these agents had minimal effects on thapsigargin (TG)-induced Ca2+ influx. These LTCC-modulating agents regulated IgE+Ag-induced cell activation but not TG-induced cell activation. Inhibition of SOCs by 2-aminoethoxydiphenyl borate reduced both degranulation and production of cytokines, including interleukin-13 and tumor necrosis factor-α, whereas LTCC modulation reciprocally regulated degranulation and cytokine production. IgE+Ag, but not TG, induced substantial plasma membrane depolarization, which stimulated a DHP-sensitive Ca2+ response. Moreover, IgE+Ag-, but not TG-induced mitochondrial Ca2+ increase was regulated by LTCC modulators. Finally, gene silencing analyses using small interfering RNA revealed that the α1C (CaV1.2) LTCC mediated the pharmacological effects of the LTCC-modulating agents. These results demonstrate that mast cells express LTCCs, which becomes activated by membrane depolarization to regulate cytosolic and mitochondrial Ca2+, thereby controlling mast cell activation in a distinct manner from SOCs. [Copyright &y& Elsevier]

Abstract: Advanced glycation end products (AGEs) accumulate during aging and to higher extents under pathological conditions such as diabetes. Since we previously showed that mast cells expressed the AGE-binding protein, receptor for AGEs (RAGE) on their cell surface, we examined whether AGE affected mast cell survival. Herein, we demonstrate that mast cells undergo apoptosis in response to AGE. Glycated albumin (GA), an AGE, but not stimulation with the high-affinity IgE receptor (FcɛRI), can induce mast cell death, as measured by annexin V/propidium iodide double-staining. GA (≥0.1 mg/ml) exhibited this pro-apoptotic activity in a concentration-dependent manner. GA and FcɛRI stimulation increased the cytosolic Ca2+ levels to a similar extent, whereas GA, but not FcɛRI stimulation, caused mitochondrial Ca2+ overload and membrane potential collapse, resulting in mitochondrial integrity disruption, cytochrome c release and caspase-3/7 activation. In addition, GA, but not FcɛRI stimulation, induced extracellular release of superoxide from mitochondria, and this release played a key role in the disruption of Ca2+ homeostasis. Knockdown of RAGE expression using small interfering RNA abolished GA-induced apoptosis, mitochondrial Ca2+ overload, and superoxide release, demonstrating that RAGE mediates the GA-induced mitochondrial death pathway. AGE-induced mast cell apoptosis may contribute to the immunocompromised and inflammatory conditions. [Copyright &y& Elsevier]

Abstract: Isotactic polypropylene (iPP)–polystyrene (PS) and iPP–poly(methyl methacrylate) (PMMA) multiblock copolymers were synthesized by atom transfer radical coupling (ATRC) of PS–iPP–PS and PMMA–iPP–PMMA triblock copolymers obtained by atom transfer radical polymerization (ATRP) of styrene (St) and methyl methacrylate (MMA), respectively, using α,ω-dibromoisobutyrateoligopropylene (iPP–Br) as a bifunctional macroinitiator. The iPP–Br was prepared by hydroxylation and subsequent esterification of telechelic oligopropylene having terminal vinylidene double bonds at both ends obtained by controlled thermal degradation of iPP. ATRP of St and (meth) acrylic monomers using iPP–Br formed the corresponding triblock copolymers. It was confirmed that the PMMA–iPP–PMMA triblock copolymer was effective as the compatibilizer for the iPP/PMMA blend. An iPP–PS multiblock copolymer (M n: 25 000g/mol and M w/M n: 4.1) was prepared by ATRC of PS–iPP–PS triblock copolymer (M n: 8900g/mol and M w/M n: 1.3). ATRC with St of PMMA–iPP–PMMA triblock copolymer (M n: 13 000g/mol and M w/M n: 1.4) provided an iPP–PMMA multiblock copolymer containing St chains (M n: 39 000g/mol and M w/M n: 2.8). [Copyright &y& Elsevier]

Abstract: Galectin-1 and galectin-3 are the most ubiquitously expressed members of the galectin family and more importantly, these two molecules are shown to have opposite effects on pro-inflammatory responses and/or apoptosis depending on the cell type. Herein, we demonstrate for the first time that galectin-3 induces mast cell apoptosis. Mast cells expressed substantial levels of galectin-3 and galectin-1 and to a lesser extent the receptor for advanced glycation end products (RAGE) on their surfaces. Treatment of cells with galectin-3 at concentrations of ≥100 nM for 18–44 h resulted in cell death by apoptosis. Galectin-3-induced apoptosis was completely prevented by lactose, neutralizing antibody to RAGE, and the caspase-3 inhibitor z-DEVD-fmk. Galectin-3-induced apoptosis was also completely abolished by dithiothreitol and superoxide dismutase, but not inhibited by catalase. Moreover, galectin-3 but not galectin-1 induced the release of superoxide, which was blocked by lactose, anti-RAGE, and dithiothreitol. Finally, galectin-3-induced apoptosis was blocked by bongkrekic acid, an antagonist of the mitochondrial permeability transition pore (PTP), while atractyloside, an agonist of the PTP, greatly facilitated galectin-1-induced apoptosis. These data suggest that galectin-3 induces oxidative stress, PTP opening, and the caspase-dependent death pathway by binding to putative surface receptors including RAGE via the carbohydrate recognition domain. [Copyright &y& Elsevier]

Abstract: Earlier studies have demonstrated that mast cells produce reactive oxygen species (ROS), which play a role in regulating Ca2+ influx, while in other cell types ROS are produced in a Ca2+-dependent manner. We sought to determine whether ROS are produced downstream of the extracellular Ca2+ entry in mast cells. Thapsigargin (TG), a receptor-independent agonist, could evoke a robust burst of intracellular ROS. However, this response was distinct from the antigen-induced burst of ROS with respect to time course and dependence on Ca2+ and phosphatidylinositol-3-kinase (PI3K). The antigen-induced ROS generation occurred immediately, while the TG-induced ROS generation occurred with a significant lag time (∼2 min). Antigen but not TG caused extracellular release of superoxide (O2 −)/hydrogen peroxide (H2O2), which was blocked by diphenyleneiodonium, apocynin, and wortmannin. A capacitative Ca2+ entry resulted in the generation of O2 − in the mitochondria in a PI3K-independent manner. Blockade of ROS generation inhibited TG-induced mediator release. Finally, when used together, antigen and TG evoked the release of leukotriene C4, tumor necrosis factor-α, and interleukin-13 as well as ROS generation synergistically. These results suggest that ROS produced upstream of Ca2+ influx by NADPH oxidase and downstream of Ca2+ influx by the mitochondria regulate the proinflammatory response of mast cells. [Copyright &y& Elsevier]

Abstract: A growing body of evidence suggests that mitochondria take up calcium upon receptor (agonist) stimulation and that this contributes to the dynamics of spatiotemporal calcium signaling. We have previously shown that engagement of the high-affinity receptor for immunoglobulin E (FcɛRI) stimulates mitochondrial calcium ([Ca2+]m) uptake in mast cells. The present study was undertaken to investigate the mechanisms and biological significance of FcɛRI regulation of [Ca2+]m. Antigen stimulated [Ca2+]m uptake in a dose-dependent manner with a minimal effective dose of 0.03–3ng/ml. This [Ca2+]m uptake took place immediately, reaching its peak within minutes and was inhibited by the src family kinase inhibitor PP1 and phosphatidylinositol-3-kinase inhibitor wortmannin. Analyses using mast cells expressing the wild-type or the mutated type of the FcɛRIβ immunoreceptor tyrosine-based activation motif (ITAM) in which all tyrosine residues were replaced by phenylalanine revealed that the FcɛRIβ ITAM is essential for a sustained [Ca2+]m uptake. The FcɛRIβ ITAM was essential for overall calcium response upon weak FcɛRI stimulation (at low antigen concentration), while upon strong stimulation (at high antigen concentration) it appeared necessary selectively to an immediate calcium response that was sensitive to the dihydropyridine receptor (DHPR) antagonist nifedipine and wortmannin but not to the store-operated calcium entry (SOCE) antagonists such as 2-aminoethoxyphenyl borate and SK&F96365. These data demonstrate that the FcɛRIβ regulates [Ca2+]m uptake in mast cells via the ITAM and suggest that this plays a key role in regulating calcium influx especially that induced via a DHPR-mediated calcium channel. [Copyright &y& Elsevier]

Abstract: In genetically susceptible human and/or experimental animals, heavy metals such as mercury, gold, and silver have been shown to highly induce adverse immunological reactions such as allergy and autoimmunity, in which mast cell degranulation is implicated as playing a role. We previously reported that silver activates mast cells and induces Ca2+ influx without stimulating intracellular signaling events required for activation of store-operated Ca2+ channels (SOCs). The purpose of the present study was to elucidate the possible involvement of reactive oxygen species (ROS) in the biological effects of silver. Analysis using oxidant-sensitive fluorescent probes such as dichlorodihydrofluorescein and scopoletin, as well as MCLA-amplified chemiluminescence, showed that silver induced intracellular production and/or extracellular release of ROS. Silver induced mast cell degranulation in a Ca2+-dependent manner. Unlike IgE antigen, silver-induced Ca2+ influx was not affected by depletion of internal Ca2+ stores. Instead, the metal-induced Ca2+ influx was abolished and reversed by the cell-impermeant thiol-reducing agent dithiothreitol, indicating the regulation by oxidation of vicinal thiols on the cell surface. Consistent with this view, Ca2+ influx was blocked by the glutathione peroxidase mimetic ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one) and the superoxide dismutase mimetic manganese(III) tetrakis 4-(benzoic acid)porphyrin, but not by exogenously added catalase or superoxide dismutase. These findings indicate that silver evokes the release of ROS and oxidation of thiols critical for the activation of a Ca2+ channel other than SOC. Such a novel ROS-dependent pathway might play a role in mast cell degranulation in metal-induced allergic and autoimmune reactions. [Copyright &y& Elsevier]

Abstract: The growth of dense green seaweed mats of Ulva spp. is an increasing problem in estuaries and coasts worldwide. The enormous amount of Ulva biomass thus becomes a troublesome waste disposal problem. On the other hand, it has been revealed that nonliving seaweed biomass, particularly brown seaweeds, has a high capacity for assimilating heavy metals. In this study, the possibility of using Ulva seaweed biomass as a biosorbent for the removal of heavy metals was examined. After processing, the biomass material was very easy to separate from the aqueous solution using a mesh. The sorption capacity of Cd on Ulva biomass increased upon pretreatment with alkali solution. The outstanding function of the biosorbent was demonstrated at around pH 8. On the basis of the Langmuir isotherms of Cd, Zn and Cu using the alkali-pretreated biomass, the parameters q m and b were determined to be within the narrow range of 60–90mg/g and 0.03–0.04L/mg, respectively, for each metal. Given the q m and b values, Ulva seaweed is a good biosorbent material for removing heavy metals. In an experiment using artificial wastewater containing Cd, Zn, Cu, Cr and Ni, it was possible to remove each metal simultaneously using Ulva biomass. Adsorption by Ulva biomass is effective for the removal of heavy metals from wastewater. [Copyright &y& Elsevier]

The development of a closed recirculating aquaculture system that does not discharge effluents would reduce a large amount of pollutant load on aquatic bodies. In this study, eel were reared in a closed recirculating system, which consisted of a rearing tank, a foam separation unit, a nitrification unit and a denitrification unit. The foam separation unit has an inhalation-type aerator and supplies air bubbles to the rearing water. The growth of eel, which were fed a commercial diet, was satisfactory, with gross weight increases of up three times in 3 months. The survival rate under the congested experimental conditions was 91%. The foam separation unit maintained oxygen saturation in the rearing water at about 80%. Furthermore, fine colloidal substances were absorbed on the stable foam formed from eel mucus and were removed from the rearing water by foam separation. Ammonia oxidation and the removal of suspended solids were accomplished rapidly and simultaneously in the nitrification unit. The ammonia concentration and turbidity were kept at less than 1.2 mg of N per litre and 2.5 units, respectively. When the denitrification process was operated, nitrate that accumulated in the rearing water (151 mg of N per litre) was reduced to 40 mg of N per litre. The sludge was easily recovered from the nitrification and denitrification tanks, and the components were found suitable as compost. Based on these results, the intensive aquaculture of freshwater fish such as eel can be achieved using a closed recirculating system without emission. [Copyright &y& Elsevier]

By using several kinds of surface-active proteins as a chemical agent that combined collector with frother, removal of suspended substances by coagulation and foam separation with dispersed air was examined. Milk casein showed the greatest capability of suspension removal, and coagulating flocs formed by clay particles and iron hydroxide were almost perfectly recovered in foam generated from the liquid, even in the case of freshwater and seawater suspension at neutral pH. In contrast, the removal efficiency was extremely low using sodium dodecyl sulfate (SDS). Casein had a much greater capability for removing solids than SDS as a result of the high adsorptive activity of casein on the floc. For municipal wastewater treatment, the removal efficiency of turbidity and suspended solids was over 98% with the condition of iron coagulant (FeCl3) 20 mg-Fe/L and casein 3 mg/L and pH 5–6. Moreover, this method proved to be an effective treatment for polluted saline water (salinity 1.5%), and the suspended solids were almost perfectly recovered in foam. Here, we show a new method for quickly removing (within 7 min) suspended solids from polluted wastewater utilizing casein and bubbles. [Copyright &y& Elsevier]

Hydrogen production from renewable electricity offers an eco-friendly alternative to fossil fuels. Proton exchange membrane (PEM) electrolysis is a well-known method for this purpose. Studies have primarily focused on reducing costs of noble catalysts, improving efficiency, managing system degradation, and addressing membrane thinning caused by contaminated cations. However, techniques for PEM recovery post-degradation are still under development. This study investigated the effects of cations on PEM cells using artificial soft water, and analyzed two recovery methods to restore cell performance. Our findings indicate a significant rise in cell operating voltage and a decrease hydrogen production over 8 h of operation with soft water. After introducing both recovery methods, the initial operating value was reinstated in both cases. Only nitric acid treatment, however, achieved hydrogen production levels comparable to those of ultrapure water. • The cations contaminated by soft water diminished the MEA cell performance. • We investigate two recovery methods to regain cell voltage and hydrogen generation. • Nitric acid treatment could provide an effective way to recover the cell performance. [ABSTRACT FROM AUTHOR]