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In enhanced biological phosphorus removal (EBPR) processes, activated sludge microorganisms accumulate large quantities of polyphosphate (polyP) intracellularly. We previously discovered that nearly all of polyP could be released from waste activated sludge simply by heating it at 70 degrees C for about 1 h. We also demonstrated that this simple method was applicable to phosphorus (P) recovery from waste activated sludge in a pilot plant-scale EBPR process. In the present study, we evaluated the effect of this sludge processing (heat treatment followed by calcium phosphate precipitation) on anaerobic digestion in laboratory-scale experiments. The results suggested that the sludge processing for P recovery could improve digestive efficiency and methane productivity at both mesophilic (37 degrees C) and thermophilic (53 degrees C) temperatures. In addition, heat-treated waste sludge released far less P into the digested sludge liquor than did untreated waste sludge. It is likely that the P recovery step prior to anaerobic digestion has a potential advantage for controlling struvite (magnesium ammonium phosphate) deposit problems in sludge handling processes.

Brain-derived neurotrophic factor (BDNF), a member of the neurotrophins, has been reported to ameliorate hyperglycemia in obese diabetic animal models. To elucidate the mechanism of BDNF on glucose metabolism, we determined the glucose turnover under basal and euglycemic hyperinsulinemic (insulin infusion rate, 54 pmol · kg−1 · min−1) clamp conditions in obese insulin-resistant rats, male Zucker fatty rats, which had been acutely administered a subcutaneous injection of BDNF (20 mg/kg) (n = 9, BDNF) or vehicle (n = 8, vehicle). Under the basal condition, acute administration of BDNF did not affect the blood glucose level, plasma insulin level, rate of glucose disappearance (Rd), and endogenous glucose production (EGP). Under the clamp condition, the glucose infusion rate (GIR) was significantly higher in BDNF than in vehicle (mean ± SD, 61.4 ± 19.1 v 41.4 ± 4.9 μmol · kg−1 · min−1, P

The biological process for phosphorus removal from wastewater is based on the use of bacteria capable of accumulating inorganic polyphosphate (polyp). We previously showed that a phoU mutation leads to polyp accumulation in Escherichia coli. The phoU mutant could be easily screened on agar plates containing 5-bromo-4-chloro-3-indolyl-phosphate (X-P(i)) after N-methyl-N'-vitro-N-nitrosoguanidine (NTG) mutagenesis. Here, we demonstrate that this method is also useful for screening polyp-accumulating mutants of bacterial strains isolated from soil and activated sludge samples.

In enhanced biological phosphorus removal (EBPR) processes, activated sludge microorganisms accumulate large quantities of polyphosphate (polyP) intracellularly. We previously discovered that nearly all of the polyP could be released from activated sludge simply by heating it at 70°C for about I h. The addition of CaCl 2 precipitated the released polyP at room temperature without pH adjustment. In the present study, we examined the feasibility of this simple technique for recovering phosphorus (P) from municipal wastewater at pilot plant scale. The pilot plant tests demonstrated an average P recovery of about 40% over the one-year operating period.

A new homogeneous insulin assay requiring no chemical modification of an insulin recognition domain, which can be applied to continuous monitoring of the time-dependent cellular response in vitro, was developed. The carboxy-terminal α-chain (αCT) segment and first leucine-rich-repeat (L1) domain in the primary binding site on the insulin receptor were genetically fused with a bioluminescent protein (Nanoluc, Nluc) and a fluorescent protein (yellow fluorescent protein, YPet) to produce the insulin-sensing probe proteins Nluc-αCT and L1-YPet. The BRET signal was observed on simple mixing of insulin with these protein probes, in a so-called homogeneous assay. The BRET signal was proportional to the insulin concentration, and the lower detection limit was 0.8 μM. Time-dependent insulin secretion from drug-stimulated MIN6 cells was also successfully monitored continuously with the probe proteins. This BRET-based homogeneous insulin assay method is thus expected to be applicable to drug development by high-throughput screening.

Recent studies have implicated epigenetics in the pathophysiology of diabetes. Furthermore, DNA methylation, which irreversibly deactivates gene transcription, of the insulin promoter, particularly the cAMP response element, is increased in diabetes patients. However, the underlying mechanism remains unclear. We aimed to investigate insulin promoter DNA methylation in an over-nutrition state. INS-1 cells, the rat pancreatic beta cell line, were cultured under normal-culture-glucose (11.2 mmol/l) or experimental-high-glucose (22.4 mmol/l) conditions for 14 days, with or without 0.4 mmol/l palmitate. DNA methylation of the rat insulin 1 gene (Ins1) promoter was investigated using bisulfite sequencing and pyrosequencing analysis. Experimental-high-glucose conditions significantly suppressed insulin mRNA and increased DNA methylation at all five CpG sites within the Ins1 promoter, including the cAMP response element, in a time-dependent and glucose concentration-dependent manner. DNA methylation under experimental-high-glucose conditions was unique to the Ins1 promoter; however, palmitate did not affect DNA methylation. Artificial methylation of Ins1 promoter significantly suppressed promoter-driven luciferase activity, and a DNA methylation inhibitor significantly improved insulin mRNA suppression by experimental-high-glucose conditions. Experimental-high-glucose conditions significantly increased DNA methyltransferase activity and decreased ten-eleven-translocation methylcytosine dioxygenase activity. Oxidative stress and endoplasmic reticulum stress did not affect DNA methylation of the Ins1 promoter. High glucose but not palmitate increased ectopic triacylglycerol accumulation parallel to DNA methylation. Metformin upregulated insulin gene expression and suppressed DNA methylation and ectopic triacylglycerol accumulation. Finally, DNA methylation of the Ins1 promoter increased in isolated islets from Zucker diabetic fatty rats. This study helps to clarify the effect of an over-nutrition state on DNA methylation of the Ins1 promoter in pancreatic beta cells. It provides new insights into the irreversible pathophysiology of diabetes.

Infection by the intestinal nematode Nippostrongylus brasiliensis induces acceleration of apoptosis in the small intestinal villus epithelial cells in vivo. In the present study, we examined whether worm extract or excretory-secretory product induces apoptosis in the rat intestinal epithelial cell line IEC-6 in vitro. In the presence of worm extract or excretory-secretory product (≥6 μg/ml), IEC-6 cell growth was significantly suppressed, and there was a concomitant increase in the number of detached cells in culture dishes. Detached cells showed nuclear fragmentation, activation of caspase-3, and specific cleavage of poly(ADP-ribose) polymerase, suggesting that apoptosis was induced in these cells. Semiquantitative reverse transcription-PCR showed that expression of Fas (CD95) mRNA was up-regulated as early as 6 h after addition of excretory-secretory product, while Fas ligand expression and p53 expression were not up-regulated. Fluorescence-activated cell sorter analyses revealed a significant increase in Fas expression and a slight increase in FasL expression in IEC-6 cells cultured in the presence of excretory-secretory product, while control IEC-6 cells expressed neither Fas or FasL. These results indicated that N. brasiliensis worms produce and secrete biologically active molecules that trigger apoptosis in intestinal epithelial cells together with up-regulation of Fas expression, although the mechanism of induction of apoptosis remains to be elucidated.

Oxidative stress is induced under diabetic conditions and causes various forms of tissue damage in patients with diabetes. Recently, pancreatic beta-cells have emerged as a putative target of oxidative stress-induced tissue damage and this seems to explain in part the progressive deterioration of beta-cell function in type 2 diabetes. As a step toward clinical trial of antioxidant for type 2 diabetes, we investigated the possible anti-diabetic effects of probucol, an antioxidant widely used as an anti-hyperlipidemic agent, on preservation of beta-cell function in diabetic C57BL/KsJ-db/db mice. Probucol-containing diet was given to mice from 6 to 16 weeks of age. Immunostaining for oxidative stress markers such as 4-hydroxy-2-nonenal (HNE)-modified proteins and heme oxygenase-1 revealed that probucol treatment decreased reactive oxygen species (ROS) in pancreatic islets of diabetic animals. Oxidative stress is known to enhance apoptosis of beta-cells and to suppress insulin biosynthesis, but probucol treatment led to preservation of beta-cell mass and the insulin content. According to intraperitoneal glucose tolerance tests, the probucol treatment preserved glucose-stimulated insulin secretion and improved glucose tolerance at 10 and 16 weeks: insulin, 280+/-82 vs. 914+/-238 pmol/l (120 min, at 16 weeks; P

In enhanced biological phosphorus removal processes, activated sludge microorganisms accumulate large quantities of polyphosphate (polyP). It was discovered that nearly all of the polyP could be released from activated sludge simply by heating it at 70 degrees C for about 1 h. The chain length of released polyP ranged from 100 to 200 phosphate (P(i)) residues. The addition of CaCl(2) precipitated approximately 75% of the total phosphorus without pH adjustment. The formed precipitate contained more P and less Ca than typical natural phosphorite deposits. Hence, in combination with enhanced biological phosphorus removal, the present method has potential for the development of a simple process for recovering phosphorus in a reusable form from wastewater.

The cbbL and cbbS genes encoding form I ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) large and small subunits in the ammonia-oxidizing bacterium Nitrosomonas sp. strain ENI-11 were cloned and sequenced. The deduced gene products, CbbL and CbbS, had 93 and 87% identity with Thiobacillus intermedius CbbL and Nitrobacter winogradskyi CbbS, respectively. Expression of cbbL and cbbS in Escherichia coli led to the detection of RubisCO activity in the presence of 0.1 mM isopropyl-β-D-thiogalactopyranoside (IPTG). To our knowledge, this is the first paper to report the genes involved in the carbon fixation reaction in chemolithotrophic ammonia-oxidizing bacteria.

The gene (empI) encoding an extracellular metal protease was isolated from a Pseudoalteromonas sp. strain A28 DNA library. The recombinant EmpI protein was expressed in E. coli and purified. Paper-disk assays showed that the purified protease had potent algicidal activity. A skim milk-polyacrylamide gel electrophoresis protease assay showed that the 38-kDa band of protease activity, which co-migrated with purified EmpI and was sensitive to 1,10-phenathroline, was detected in the extracellular supernatant of A28.

We examined a possible association between subclinical hypothyroidism and albuminuria in 159 people with type 2 diabetes. Patients with subclinical hypothyroidism had significantly higher levels of urinary albumin-to-creatinine ratio (UACR) than those with euthyroidism. Multivariate logistic regression analyses demonstrated that serum TSH level was an independent risk factor of albuminuria.

The aim of this study was to examine the possible association between YKL-40, a new biomarker of endothelial dysfunction, and albuminuria in 180 type 2 diabetic patients. Multivariate logistic regression analyses demonstrated that serum YKL-40 level was a determinant of albuminuria independently of conventional risk factors.

OBJECTIVE We examined the relationship between the presence and extent of coronary stenosis and carotid intima-media thickness (CIMT) in type 2 diabetic patients without history of coronary artery disease (CAD) but with carotid atherosclerosis. RESEARCH DESIGN AND METHODS A total of 91 type 2 diabetic patients underwent multi-slice computed tomography coronary angiography. RESULTS Max-IMT in the ≥50% stenosis group by multi-slice computed tomography coronary angiography estimation was significantly greater than the 0–25 and 25–50% stenosis group (2.68 ± 0.77 vs. 1.61 ± 0.49 mm, P < 0.0005, and 2.14 ± 0.81 mm, P < 0.05, respectively), and max-IMT in the 25–50% stenosis group was significantly greater than the 0–25% stenosis group (P < 0.05) after adjustment for age, sex, duration of type 2 diabetes, hypertension, and dyslipidemia. In the analysis for trend through the categories of max-IMT, as max-IMT increased, the percentage of ≥50% stenosis increased and the percentage of 0–25% stenosis decreased. CONCLUSIONS Our data suggest that max-IMT might be closely associated with the extent of coronary stenosis in type 2 diabetic patients without history of CAD but with carotid atherosclerosis.

An emerging alternative to the commonly used analytical methods for asbestos analysis is fluorescence microscopy (FM), which relies on highly specific asbestos-binding probes to distinguish asbestos from interfering non-asbestos fibers. However, all types of microscopic asbestos analysis require laborious examination of large number of fields of view and are prone to subjective errors and large variability between asbestos counts by different analysts and laboratories. A possible solution to these problems is automated counting of asbestos fibers by image analysis software, which would lower the cost and increase the reliability of asbestos testing. This study seeks to develop a fiber recognition and counting software for FM-based asbestos analysis. We discuss the main features of the developed software and the results of its testing. Software testing showed good correlation between automated and manual counts for the samples with medium and high fiber concentrations. At low fiber concentrations, the automated counts were less accurate, leading us to implement correction mode for automated counts. While the full automation of asbestos analysis would require further improvements in accuracy of fiber identification, the developed software could already assist professional asbestos analysts and record detailed fiber dimensions for the use in epidemiological research.

We developed a sensitive method for detecting adenosine monophosphate (AMP) by using polyphosphate (polyP)–AMP phosphotransferase (PPT) and adenylate kinase (ADK) from Acinetobacter johnsonii in conjugation with firefly luciferase. This method allowed us to detect AMP over the concentration range of 0.3–300 pmol per assay. Samples taken from various sources susceptible to bacterial contamination were subjected to AMP assay using the present method because AMP is known to have potential for use as a reliable indicator in hygiene monitoring. The results showed that the present method was able to detect food residues with high sensitivity. The present method was also proved to be useful for the quantification of RNA. After digesting RNA with nuclease S1, the present method could detect RNA at concentrations as low as 600 pg.

Inorganic polyphosphate (polyP), a polymer of hundreds of phosphate (P i ) residues, accumulates in Escherichia coli in response to stresses, including amino acid starvation. Here we show that the adenosine 5′-triphosphate–dependent protease Lon formed a complex with polyP and degraded most of the ribosomal proteins, including S2, L9, and L13. Purified S2 also bound to polyP and formed a complex with Lon in the presence of polyP. Thus, polyP may promote ribosomal protein degradation by the Lon protease, thereby supplying the amino acids needed to respond to starvation.

Inorganic polyphosphate (polyP) kinase was studied for its roles in physiological responses to nutritional deprivation in Escherichia coli . A mutant lacking polyP kinase exhibited an extended lag phase of growth, when shifted from a rich to a minimal medium (nutritional downshift). Supplementation of amino acids to the minimal medium abolished the extended growth lag of the mutant. Levels of the stringent response factor, guanosine 5′-diphosphate 3′-diphosphate, increased in response to the nutritional downshift, but, unlike in the wild type, the levels were sustained in the mutant. These results suggested that the mutant was impaired in the induction of amino acid biosynthetic enzymes. The expression of an amino acid biosynthetic gene, hisG , was examined by using a transcriptional lacZ fusion. Although the mutant did not express the fusion in response to the nutritional downshift, Northern blot analysis revealed a significant increase of hisG-lacZ mRNA. Amino acids generated by intracellular protein degradation are very important for the synthesis of enzymes at the onset of starvation. In the wild type, the rate of protein degradation increased in response to the nutritional downshift whereas it did not in the mutant. Supplementation of amino acids at low concentrations to the minimal medium enabled the mutant to express the hisG-lacZ fusion. Thus, the impaired regulation of protein degradation results in the adaptation defect, suggesting that polyP kinase is required to stimulate protein degradation.

Two chemotaxis-defective mutants of Pseudomonas aeruginosa, designated PC3 and PC4, were selected by the swarm plate method after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. These mutants were not complemented by the P. aeruginosa cheY and cheZ genes, which had been previously cloned (Masduki et al., J. Bacteriol., 177, 948-952, 1995). DNA sequences downstream of the cheY and cheZ genes were able to complement PC3 but not PC4. Sequence analysis of a 9.7-kb region directly downstream of the cheZ gene found three chemotaxis genes, cheA, cheB, and cheW, and seven unknown open reading frames (ORFs). The predicted translation products of the cheA, cheB, and cheW genes showed 33, 36, and 31% amino acid identity with Escherichia coli CheA, CheB, and CheW, respectively. Two of the unknown ORFs, ORF1 and ORF2, encoded putative polypeptides that resembled Bacillus subtilis MotA (40% amino acid identity) and MotB (34% amino acid identity) proteins, respectively. Although P. aeruginosa was found to have proteins similar to the enteric chemotaxis proteins CheA, CheB, CheW, CheY, and CheZ, the gene encoding a CheR homologue did not reside in the chemotaxis gene cluster. The P. aeruginosa cheR gene could be cloned by phenotypic complementation of the PC4 mutant. This gene was located at least 1,800 kb away from the chemotaxis gene cluster and encoded a putative polypeptide that had 32% amino acid identity with E. coli CheR.

The pstSCAB genes of Pseudomonas putida PRS2000, encoding the phosphate (Pi)-specific transport (Pst) system, were cloned. The pstS gene of Pseudomonas aeruginosa PAO1, of which the pstCAB genes had been cloned previously, was also cloned (Nikata, T. et al., Mol. Gen. Genet., 250, 692-698, 1996). The predicted translation products of the P. putida pstSCAB genes showed 83, 75, 78 and 88% amino acid identity with their P. aeruginosa counterparts. Two well-conserved Pho box sequences were found in the region upstream of the pstS gene (15/18 base identity with the consensus Pho box sequence) and in the intercistronic region between the pstS and pstC genes (11/18 base identity) of P. putida PRS2000. To investigate the functions of PstSCAB, the pstSC genes were inactivated by inserting a kanamycin resistance gene cassette into the chromosome of P. putida PRS2000. The resultant mutant, designated PNT1, failed to take up 32Pi even under conditions of Pi limitation. Strain PNT1 was also constitutive for alkaline phosphatase synthesis, as well as chemotaxis toward Pi, indicating that the Pst system is involved in the negative regulation of the pho regulon in P. putida. Although overexpression of the pstSCAB genes in P. putida PRS2000 resulted in decreased cell growth, this recombinant strain could remove Pi at a rate similar to that seen with the control strain.

Heat-treated Escherichia coli producing Thermus polyphosphate kinase regenerated ATP by using exogenous polyphosphate. This recombinant could be used as a platform to produce valuable compounds in combination with thermostable phosphorylating or energy-requiring enzymes. In this work, we demonstrated the production of fructose 1,6-diphosphate from fructose and polyphosphate.

Phosphorus (P) is an essential constituent in all types of living organisms. Bacteria, which use inorganic phosphate (Pi), as the preferred P source, have evolved complex systems to survive during Pi starvation conditions. Recently, we found thatPseudomonas aeruginosa, a monoflagellated, obligately aerobic bacterium, is attracted to Pi. The evidence that the chemotactic response to Pi (Pi taxis) was observed only with cells grown in Pi-limiting medium suggests that Pi taxis plays an important role in scavenging Pi residues under conditions of Pi starvation. Many bacteria also exhibit rapid and extensive accumulation of polyphosphate (polyP), when Pi is added to cells previously subjected to Pi starvation stress. Since polyP can serve as a P source during Pi starvation conditions, it is likely that polyP accumulation is a protective mechanism for survival during Pi starvation. In the present review, we summarize our current knowledge on regulation of bacterial Pi taxis and polyP accumulation in response to Pi starvation stress.

Klebsiella aerogenes ATCC 9621 was able to utilize phosphonates (P n ), including aminoethylphosphonate, ethylphosphonate, methylphosphonate (MP n ), and phosphonoacetate, and inorganic phosphite (P t ) as sole sources of phosphorus (P). The products of the phn gene cluster were absolutely required for P n breakdown and P t oxidation to inorganic phosphate (P i ) in this organism. To determine if K. aerogenes ATCC 9621 could be engineered to enhance the utilization of P n and P t , a multicopy plasmid, pBI05, which carried the entire phn gene cluster, was introduced into this strain. Despite the increased dosage of the phn genes, K. aerogenes ATCC 9621(pBI05) could utilize only up to 1.1-fold more P n and P t than did the control strain with the parent vector alone. These results suggested that P i , which was generated from P n and P t , might limit further utilization of these P compounds. Consequently, to convert the resulting P i to polyphosphate (polyP), the plasmid pKP28, which carried the K. aerogenes ppk gene (which encodes polyP kinase), was introduced into K. aerogenes ATCC 9621(pBI05). Overexpression of the ppk gene in K. aerogenes ATCC 9621(pBI05, pKP28) resulted in a 2.5-fold increase in P t utilization over that of the control strain. This recombinant strain also accumulated approximately sixfold more P than did the control strain when the cells were grown with MP n as a sole source of P.

It is expected that biotechnology plays a central role in making and keeping the environment clean. Most biological agents used for this purpose are microorganisms. A variety of cellular functions of microorganisms are potentially applicable to pollution prevention. These include dissimilatory oxidation and reduction of inorganic compounds, photosynthesis, co-metabolism of xenobiotics, biopolymer formation, and enzymatic transformation of heavy metals. The potential for using biological agents will be far greater if their abilities are enhanced by increasing the dosage of key genes and modifying their genetic regulation. The present review describes current efforts directed towards the genetic improvement of bacterial abilities to remove phosphorus and nitrogen compounds that are priority targets for controlling the eutrophication in natural bodies of water.

We recently reported that silica is deposited on the coat of Bacillus cereus spores as a layer of nanometer-sized particles (Hirota et al. 2010 J Bacteriol 192: 111-116). Gene disruption analysis revealed that the spore coat protein CotB1 mediates the accumulation of silica (our unpublished results). Here, we report that B. cereus CotB1 (171 amino acids [aa]) and its C-terminal 14-aa region (corresponding to residues 158-171, designated CotB1p) show strong affinity for silica particles, with dissociation constants at pH 8.0 of 2.09 and 1.24 nM, respectively. Using CotB1 and CotB1p as silica-binding tags, we developed a silica-based affinity purification method in which silica particles are used as an adsorbent for CotB1/CotB1p fusion proteins. Small ubiquitin-like modifier (SUMO) technology was employed to release the target proteins from the adsorbed fusion proteins. SUMO-protease-mediated site-specific cleavage at the C-terminus of the fused SUMO sequence released the tagless target proteins into the liquid phase while leaving the tag region still bound to the solid phase. Using the fluorescent protein mCherry as a model, our purification method achieved 85 % recovery, with a purity of 95 % and yields of 0.60 ± 0.06 and 1.13 ± 0.13 mg per 10-mL bacterial culture for the CotB1-SUMO-mCherry and CotB1p-SUMO-mCherry fusions, respectively. CotB1p, a short 14-aa peptide, which demonstrates high affinity for silica, could be a promising fusion tag for both affinity purification and enzyme immobilization on silica supports.

Recently the silicon photonics is attracting much attention because photonic devices can be easily fabricated by using the matured silicon technologies. In this paper we introduce our study concerning two applications of silicon photonics, optical modulators and optical biosensors.

Enterobacter cloacae IFO3320 is attracted to Pi when cells are starved for Pi. Two Tn1737KH-induced mutants, which were constitutive for alkaline phosphatase, failed to exhibit Pi taxis even under conditions of Pi limitation. Both of the mutant strains exhibited normal chemotactic responses to peptone, suggesting that they are specifically defective in Pi taxis. Cloning and sequence analysis showed that the TN1737KH insertions were located in either the pstA or pstB genes which encode the channel-forming proteins of the Pi-specific transport (Pst) system in E. cloacae. These results suggest that the E. cloacae Pst system is required for Pi chemoreception.

High levels of guanosine tetraphosphate (ppGpp) and guanosine pentaphosphate (pppGpp), generated in response to amino acid starvation in Escherichia coli, lead to massive accumulations of inorganic polyphosphate (polyP). Inasmuch as the activities of the principal enzymes that synthesize and degrade polyP fluctuate only slightly, the polyP accumulation can be attributed to a singular and profound inhibition by pppGpp and/or ppGpp of the hydrolytic breakdown of polyP by exopolyphosphatase, thereby blocking the dynamic turnover of polyP. The K ivalues of 10 μm for pppGpp and 200 μm for ppGpp are far below the concentrations of these nucleotides in nutritionally stressed cells. In the complex metabolic network of pppGpp and ppGpp, the greater inhibitory effect of pppGpp (compared with ppGpp) leading to the accumulation of polyP, may have some significance in the relative roles played by these regulatory compounds.

Tacrolimus hydrate (FK506), a novel 23-membered macrolide, is an immunosuppressant isolated from Streptomyces tsukubaensis using extensive screening of fermentation products to identify a compound inhibiting the mixed lymphocyte reaction (MLR). The in vitro and in vivo immunosuppressive activities of FK506 were found to be more potent than those of cyclosporine (CyA). The superior immunosuppression with FK506 treatment was also confirmed in the skin allograft model in rats and liver transplantation in dogs. Clinical studies were initiated by Prof. Starzl at the University of Pittsburgh in 1989, and he demonstrated that FK506 surpassed CyA in the incidence of graft survival and the frequency of graft rejection. Multicenter randomized clinical studies, comparing FK506 to CyA corroborated the efficacy of FK506 on the survival of patients and of grafts, and especially on the appearance of severe refractory graft rejection. FK506 was marketed in 1993 in Japan, and was followed in 1994 in the U.S.A., U.K. and Germany. The mechanism of action of this compound was clarified by the endeavors of Prof. Schreiber, who demonstrated the existence of a binding protein for FK506 called FKBP, similar to cyclophilin for CyA. The FK506/FKBP complex binds with calcineurin, a serine/threonine phosphatase to inhibit the translocation of NFAT into the nucleus, resulting in inhibition of transcription of IL-2 mRNA. FK506 displays potent immunosuppressant activity, and contributes not only to the progress of transplantation therapy for clinical studies, but also to the clarification of signal transduction in T cell activation for basic science.

Pseudomonas aeruginosa possesses two aerotaxis transducers, Aer and Aer-2. A deletion-insertion mutation of alternative sigma factor RpoS eliminated Aer-2-mediated aerotaxis but not Aer-mediated aerotaxis. Transcriptional analysis revealed that cheY2 , cheA2 , cheW2 , and aer - 2 were expressed in an RpoS-dependent manner as a single transcript.

We have investigated the performance of proposed multi-slot stack-type ring resonators. For biosensors, the sensitivity is roughly proportional to the number of slots. For optical modulators, the low operation voltage

Large quantities of xenobiotic phosphonates (Pn), which are used as pesticides, detergent additives, antibiotics, and flame retardants, are released into the environment. These C-P compounds are generally resistant to chemical hydrolysis and recalcitrant to biodegradation. We have cloned the Klebsiella aerogenes phn gene cluster which is required for degrading Pn and also for oxidizing phosphite (Pt) to phosphate (Pi). Recombinant plasmids containing the phn gene cluster allowed E. coli MV1184 to grow with aminoethylphosphonate (AEPn), ethylphosphonate (EPn), methylphosphonate (MPn) and Pt as a sole source of phosphorus. Pi, which is generated by Pn breakdown and Pt oxidation, is also a priority target for controlling the eutrophication in natural bodies of water. We examined the genetic improvement of bacterial Pi accumulation by manipulating the genes involved in the key steps of Pi transport and polyphosphate (polyP) formation.

Optically active 1,1′-binaphthalene-8,8′-diol is found to bind a variety of amines in CDCl3 or C6D6 solution. Significant chiral recognition (ΔΔG° = ∼1.2 kcal/mol) was observed in the valine derivative 4. A three-point binding motif is assumed.

The organization of the phosphate-specific transport (pst) operon in Pseudomonas aeruginosa has been determined. The gene order of the pst operon is pstC, pstA, pstB, phoU, and a well-conserved Pho box sequence (16/18 bases identical) exists in the promoter region. The most striking difference from the known Escherichia coli pst operon is the lack of the pstS gene encoding a periplasmic phosphate (Pi)-binding protein. Even though the three pst genes were absolutely required for P(i)-specific transport, expression of the pst operon at high levels did not increase P(i) uptake in P. aeruginosa. DNA sequences for the pstB and phoU genes have been determined previously. The newly identified pstC and pstA genes encode possible integral membrane proteins of 677 amino acids (M(r) 73,844) and 513 amino acids (M(r) 56,394) respectively. The amino acid sequences of PstC and PstA predict that these proteins contain a long hydrophilic domain not seen in their E. coli counterparts. A chromosomal deletion of the entire pst operon rendered P. aeruginosa unable to repress P(i) taxis under conditions of P(i) excess. The phoU and pstB genes are essential for repressing P(i) taxis. However, mutants lacking either PstC or PstA alone were able to repress P(i) taxis under conditions of P(i) excess.

Subcellular antigen localization in Toxoplasma gondii was studied by immunoelectron microscopy using sera obtained from congenital toxoplasmosis neonates or the mother. IgG and IgM antibodies bound specifically to the dense granules and rhoptries, but little bound to the cytoplasm of the organism or its tegmentum. The results indicate the importance of dense granules and rhoptries as a storage site for the antigens, which would be released and stimulate antibody production in human toxoplasmosis.

We herein report the case of a 37-year-old type 1 diabetic pregnant woman treated with an insulin pump. Although the patient's glycemic control deteriorated following progesterone treatment for the prevention of preterm delivery and miscarriage, it was improved by adjusting the basal insulin rate on the days of progesterone treatment. Excess progesterone is known to impair both insulin sensitivity and secretion. The present case is the first report to evaluate deterioration of glycemic control induced by progesterone treatment and to determine the dose of insulin required in a type 1 diabetic pregnant woman whose insulin secretion was completely depleted.

We have developed signal-transducing molecules for detecting specific nucleic acids in a homogeneous assay format. A DNA nano-tweezers (DNA-NT) structure, self-assembled from three single-stranded DNAs, was employed as a main component that alters its structure from an open state to a closed state in recognition of target nucleic acids. This dynamic structural change was utilized for generating a target-specific sensing signal. A fluorescence resonance energy transfer (FRET)-paired fluorescent dyes were modified onto a DNA-NT to generate a target-specific sensing signal. This FRET-based DNA-NT alters its structure in response to target nucleic acids, resulting in the closing of the distal relation of FRET-paired fluorescent dyes. The FRET-based DNA-NT generates the FRET signal only when it recognizes target nucleic acids, and thus the target detection can be performed in a homogeneous assay format, which does not require washing procedure. Therefore, when the FRET-based DNA-NT is introduced into a cell, the continuous detection of specific target mRNA inside living cells can be realized in a non-destructive manner. Live-cell imaging analysis of drug stimulated cells with the FRET-based DNA-NTs indicated that the behaviors of the FRET signals integrated in each individual cell were similar to those of target mRNA measured with the conventional mass analysis technique of semi-quantitative real-time polymerase chain reaction. Thus, it was concluded that continuous monitoring of specific genes is feasible with a FRET-based DNA-NT, even in a single cell manner. As another example of a component for signal generation, a G-quadruplex (Gq) composed a guanine-rich DNA sequence was employed. A Gq is one of the well-characterized DNazymes that exhibits a peroxidase activity with the help of hemin as a co-factor. In our design, the split Gq sequences were added to both ends of a DNA-NT instead of the FRET-paired fluorescent dyes. This split-Gq-based DNA-NT alters its structure from an open state to a closed state, inducing the complementation of the split Gq that exhibits restored peroxidase activity. A model target RNA was specifically recognized by the split Gq-based DNA-NT. The peroxidase activity was measured by following the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), which gave a greenish colorimetric response, and was proportional to the concentration of model target RNA. The split-Gq-based DNA-NT generates a peroxidase activity only when it recognizes target nucleic acids, and thus the target detection can be performed in a homogeneous assay format that is suitable for a portable format. Therefore, the detection of specific nucleic acids with the split Gq-based DNA-NT has great potential for use in a wide variety of applications, such as point-of-care testing and point-of-need testing. The DNA-NT-based signal-transducing molecules, enabling the detection of target nucleic acids in a homogeneous assay format, recognize the target without competitive reactions in a bimolecular reaction and directly produce a readily detectable signal. Notably, the target recognition sites of DNA-NT-based signal-transducing molecules can easily be designed without delicate optimization of tweezers structure. Therefore, the DNA-NT-based signal-transducing molecules are expected to become a versatile tool for detecting specific nucleic acids.

Dosing guidelines for patients with type 1 diabetes using continuous subcutaneous insulin infusion (CSII), which are historically based on clinical experience and retrospective studies of patients consuming an American diet, recommend that basal insulin should represent approximately 50 % of the total daily dose (TDD). Recent prospective studies in the USA and Japan conclude that the more appropriate proportion is closer to 30–40 % of TDD. In addition, currently used formulas for calculating the carbohydrate-to-insulin ratio (CIR) and correction factor (CF) may lead to underdosing of bolus insulin by as much as 12.8–50 % for a hypothetical patient. The discrepancies between traditional formulas and data from newer studies can be accounted for by the more rigorous design of the newer studies (e.g., prospective design, controlled diets, meal omission, and frequent glucose monitoring). International differences in diet composition may also be important to consider when developing dosing recommendations for CSII.

Differential Si ring optical resonator sensors have been fabricated. Their detection sensitivity was 10−3–10−2% for sucrose solution, which corresponds to a sensitivity of ~1.0 ng/ml for prostate-specific antigen (PSA), which is satisfactory for practical use. In the differential sensing the input light is incident to two rings, and one of the outputs is connected to a π phase shifter then the two outputs are merged again. For the differential detection, not only is the common-mode noise canceled, resulting in high sensitivity, but also the temperature stability is much improved. A fluid channel is fabricated so that the detecting liquid flows to the detection ring and the reference liquid flows to the reference ring. We have proposed a method of obtaining a constant sensitivity for the integrated sensors even though the resonance wavelengths of the two rings of the differential sensor are slightly different. It was found that a region exists with a linear relationship between the differential output and the difference in the resonance wavelengths of the two rings. By intentionally differentiating the resonance wavelengths in this linear region, the sensors have a constant sensitivity. Many differential sensors with different ring spaces have been fabricated and the output scattering characteristics were statistically evaluated. As a result, a standard deviation of resonance wavelength σ = 8 × 10−3 nm was obtained for a ring space of 31 µm. From the width of the linear region and the standard deviation, it was estimated from the Gaussian distribution of the resonance wavelength that 93.8% of the devices have the same sensitivity.

ATP-dependent glucokinase is suggested to have evolved from a hypothetical polyphosphate (polyP)-dependent glucokinase (polyP-GK) via a bifunctional polyP/ATP glucokinase (polyP/ATP-GK). Here we showed that polyP-GK is present in a polyP-accumulating bacterium, Microlunatus phosphovorus . The polyP-GK produced glucose-6-P i from glucose and polyP, but it could not phosphorylate glucose with ATP. The polyP-GK was most closely related to the polyP/ATP-GK of Mycobacterium tuberculosis .

To optimize insulin dose using insulin pump, basal and bolus insulin doses are widely calculated from total daily insulin dose (TDD). It is recommended that total daily basal insulin dose (TBD) is 50% of TDD and that the carbohydrate-to-insulin ratio (CIR) equals 500 divided by TDD. We recently reported that basal insulin requirement is approximately 30% of TDD. We therefore investigated CIR after adjustment of the proper basal insulin rate.Forty-five Japanese patients with type 1 diabetes were investigated during several weeks of hospitalization. The patients were served standard diabetes meals (25-30 kcal/kg of ideal body weight). Each meal omission was done to confirm basal insulin rate. Target blood glucose level was set at 100 and 150 mg/dL before and 2 h after each meal, respectively. After the basal insulin rate was fixed and target blood glucose levels were achieved, TBD, CIR, TDD, and their products were determined.Mean (±SD) blood glucose levels before and 2 h after meals were 121±47 and 150±61 mg/dL, respectively. TDD was 31.5±9.0 U, and TBD was 27.0±6.5% of TDD. CIR×TDD of breakfast was significantly lower than those of lunch and supper (288±73 vs. 408±92 and 387±83, respectively; P0.01).CIR has diurnal variance and is estimated from the formula CIR=300/TDD at breakfast or CIR=400/TDD at lunch and supper in type 1 diabetes patients. These results indicate that the insulin dose has been underestimated by using previously established calculations.