The influence of microbial dysbiosis on immunochemotherapy-related efficacy and safety in diffuse large B-cell lymphoma.

The gut microbiome influences cancer development and the efficacy and safety of chemotherapy but little is known about its effects on lymphoma. We obtained stool samples from treatment-naive, newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) (n = 189). We first performed 16S ribosomal RNA gene sequencing (n = 158) and then conducted whole-genome shotgun sequencing on additional samples (n = 106). We compared the microbiome data from these patients with data from healthy controls and assessed whether microbiome characteristics were associated with treatment outcomes. The alpha diversity was significantly lower in patients with DLBCL than in healthy controls (P < .001), and the microbial composition differed significantly between the groups (P < .001). The abundance of the Enterobacteriaceae family belonging to the Proteobacteria phylum was markedly higher in patients than in healthy controls. Functional analysis of the microbiome revealed an association with opportunistic pathogenesis through type 1 pili, biofilm formation, and antibiotics resistance. Enterobacteriaceae members were significantly enriched in patients who experienced febrile neutropenia and in those who experienced relapse or progression (P < .001). Interestingly, greater abundance of Enterobacteriaceae correlated with shorter progression-free survival (P = .007). The cytokine profiles of patients whose microbiome was enriched with Enterobacteriaceae were significantly associated with interleukin 6 (P = .035) and interferon gamma (P = .045) levels. In summary, patients with DLBCL exhibited gut microbial dysbiosis. The abundance of Enterobacteriaceae correlated with treatment outcomes and febrile neutropenia. Further study is required to elucidate the origin and role of gut dysbiosis in DLBCL.

Self-Assembled Skin-Penetrating Peptides with Controlled Supramolecular Properties for Enhanced Transdermal Delivery.

The use of nanocarriers decorated with penetration-enhancing agents (PEAs) is considered to be a promising approach for efficient transdermal delivery. In this study, we developed short amphiphilic skin-penetrating peptides (17 amino acids) that functioned not only as PEAs but also as building blocks of nanocarriers without the incorporation of additional macromolecules for self-assembly and guest molecule encapsulation. Interestingly, varying only two amino acids in the hydrophobic moiety of the peptides resulted in significantly different self-assembly behavior, thermal stability, protease resistance, and skin-penetration efficiency in a human skin model. The analysis of the peptide secondary structure revealed that such characteristic changes arose due to the sequence variation-mediated conformational change in the hydrophobic block. These findings hold significant promise for the development of simple and effective delivery systems exhibiting controllable supramolecular properties.

Parasphingorhabdus cellanae sp. nov., isolated from the gut of a Korean limpet, Cellana toreuma.

A novel bacterium, designated strain JHSY0214T, was isolated from the gut of a Korean limpet, Cellana toreuma. Cells of strain JHSY0214T were Gram-stain-negative, strictly aerobic, yellow-pigmented, non-spore-forming, non-motile and showed a rod-coccus growth cycle. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain belonged to the genus Parasphingorhabdus, and was most closely related to Parasphingorhabdus litoris KCTC 12764T (98.71 %). Strain JHSY0214T had two fluoroquinolone-resistance genes and seven multidrug-resistance efflux pump genes, but did not have beta-lactamase genes and zinc resistance genes compared with P. litoris KCTC 12764T. Strain JHSY0214T grew optimally at 30 °C, pH 7.0 and in the presence of 2 % (w/v) NaCl. The predominant cellular fatty acids of strain JHSY0214T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c; 41.2 %), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 21 %) and C16 : 0 (18.9 %). The major isoprenoid quinone was ubiquinone-10. The major polar lipids were sphingoglycolipid and phosphatidylethanolamine. The genomic DNA G+C content was 52.8 mol%. Based on phylogenetic, genotypic and phenotypic data, strain JHSY0214T represents a novel species of the genus Parasphingorhabdus, for which the name Parasphingorhabdus cellanae is proposed. The type strain is JHSY0214T (=KCTC 82387T=DSM 112279T).

Anaerostipes hominis sp. nov., a novel butyrate-producing bacteria isolated from faeces of a patient with Crohn's disease.

Cultivation and isolation of gut bacteria are necessary for understanding their role in the intestinal ecosystem. We isolated a novel bacterium, designated strain BG01T, from the faeces of a patient with Crohn's disease. Strain BG01T was a strictly anaerobic, rod-shaped, Gram-variable and endospore-forming bacterium. Strain BG01T possessed C12 : 0, C18 : 0 dimethyl aldehyde (DMA) and C18 : 1 ω9c DMA as predominant cellular fatty acids and meso-diaminopimelic acid as a diagnostic diamino acid. Strain BG01T grew at 15-45 °C (optimum, 37 °C), with 0-4 % (w/v) NaCl (optimum, 0-1 %), at pH 6-10 (optimum, pH 7) and was resistant to bile salt, but not to ampicillin, metronidazole, vancomycin and cefoperazone. Butyrate, propionate, oxalacetate and fumarate were produced as fermentation end products from Gifu anaerobic medium broth. Strain BG01T showed 97.7 % 16S rRNA gene sequence similarity, and 92.0 and 48.5 % of average nucleotide identity and digital DNA-DNA hybridization values, respectively, with Anaerostipes caccae KCTC 15019T. Genomic analysis indicated that strain BG01T had a butyrate-producing pathway. The genomic G+C content of the strain was 43.5 mol%. Results of the phenotypic, phylogenetic and genotypic analyses indicated that strain BG01T represents a novel butyrate-producing species of the genus Anaerostipes, for which the name Anaerostipes hominis sp. nov. is proposed. The type strain is BG01T (=KCTC 15617T=JCM 32275T).

Chitinibacter bivalviorum sp. nov., isolated from the gut of the freshwater mussel Anodonta arcaeformis.

A novel Gram-stain-negative, aerobic, rod-shaped bacterium with a single polar flagellum, designated strain 2T18T, was isolated from the gut of the freshwater mussel Anodonta arcaeformis collected in the Republic of Korea. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Chitinibacter. Strain 2T18T formed a monophyletic clade with Chitinibacter fontanus KCTC 42982T, C. tainanensis KACC 11706T and C. alvei KCTC 23839T, with sequence similarities of 98.5, 98.4 and 95.9 %, respectively. Strain 2T18T exhibited optimal growth at 30 °C, at pH 8 and with 0.5 % (w/v) NaCl. The major isoprenoid quinone was ubiquinone-8 (Q-8). The predominant fatty acids were summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and C16 : 0. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified lipid, three unidentified phospholipids and two unidentified aminophospholipids. The G+C content of the genomic DNA was 50.6 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strains 2T18T and C. fontanus KCTC 42982T were below the thresholds used for the delineation of a novel species. Based on the phylogenetic, phenotypic, chemotaxonomic and genotypic characteristics, strain 2T18T represents a novel species of the genus Chitinibacter, for which the name Chitinibacter bivalviorum sp. nov. is proposed. The type strain is 2T18T (=KCTC 72821T=CCUG 74764T).

Brevilactibacter coleopterorum sp. nov., isolated from the intestine of the dark diving beetle Hydrophilus acuminatus, and Weissella coleopterorum sp. nov., isolated from the intestine of the diving beetle Cybister lewisianus.

A polyphasic taxonomic approach was used to characterize two novel bacterial strains, designated as HDW11T and HDW19T, isolated from intestine samples of the dark diving beetle Hydrophilus acuminatus and the diving beetle Cybister lewisianus, respectively. Both isolates were Gram-stain-positive, facultatively anaerobic and non-motile. Strain HDW11T grew optimally at 30 °C, pH 8 and in the presence of 1% (w/v) NaCl. Strain HDW19T grew optimally at 25 °C, pH 7 and in the presence of 0.3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and genome sequences revealed that strain HDW11T is a member of the genus Brevilactibacter and is closely related to Brevilactibacter flavus VG341T [with 97.9% 16S rRNA sequence identity and 79.1% average nucleotide identity (ANI)], and that strain HDW19T belongs to the genus Weissella and is closely related to W. koreensis KCTC 3621T (with 98.9% 16S rRNA sequence identity and 79.5% ANI). The major cellular fatty acids of strains HDW11T and HDW19T were C18:1 ω9c and anteiso-C15:0, respectively. The sole respiratory quinone of strain HDW11T was MK-9 (H4). The major polar lipid components of strain HDW11T were diphosphatidylglycerol and phosphatidylglycerol, and the major polar lipid component of strain HDW19T was diphosphatidylglycerol. The genomic DNA G+C content of strains HDW11T and HDW19T were 72.1 and 37.2 mol%, respectively. The results of phylogenetic, phenotypic, chemotaxonomic and genotypic analyses suggest that strain HDW11T represents a novel species within the genus Brevilactibacter, and that strain HDW19T represents a novel species within the genus Weissella. We propose the name Brevilactibacter coleopterorum sp. nov. for strain HDW11T (=KACC 21335T=KCTC 49320T=JCM 33680T) and the name Weissella coleopterorum for strain HDW19T (=KACC 21347T=KCTC 43114T=JCM 33684T).

Tessaracoccus coleopterorum sp. nov., isolated from the intestine of the dark diving beetle, Hydrophilus acuminatus.

A polyphasic taxonomic approach was used to characterize a novel bacterium, designated as strain HDW20T, isolated from the intestine of the dark diving beetle Hydrophilus acuminatus. The isolate was Gram-stain-positive, facultatively anaerobic, non-motile, coccus-shaped, and formed pale orange colonies. Phylogenetic analysis based on 16S rRNA gene sequences and genome sequences showed that the isolate belonged to the genus Tessaracoccus in the phylum Actinobacteria and was closely related to T. flavescens SST-39T, T. defluvii JCM 17540T, and T. aquimaris NSG39T, with the highest 16S rRNA gene sequence similarity of 98.5 % and a highest average nucleotide identity (ANI) value of 80.6 %. The major cellular fatty acids were C18 : 1 ω9c and anteiso-C15 : 0. The main respiratory quinone was MK-9 (H4). The major polar lipid components were phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content was 69.0 %. The isolate contains ʟʟ-diaminopimelic acid, ʟ-alanine, and ʟ-lysine as amino acid components, and ribose, glucose, and galactose as sugar components of the cell wall peptidoglycan. The results of phylogenetic, phenotypic, chemotaxonomic, and genotypic analyses suggested that strain HDW20T represents a novel species within the genus Tessaracoccus. We propose the name Tessaracoccus coleopterorum sp. nov. The type strain is HDW20T (=KACC 21348T=KCTC 49324T=JCM 33674T).

Flaviflexus ciconiae sp. nov., isolated from the faeces of the oriental stork, Ciconia boyciana.

A novel Gram-stain-positive, non-motile, non-spore-forming, coccobacillus-shaped, strictly aerobic bacterium, designated strain H23T48T, was isolated from the faecal sample of an oriental stork collected from the Seoul Grand Park Zoo in Seoul, Republic of Korea. Optimal growth of strain H23T48T was observed at 30-37 °C, pH 8 and with 3 % (w/v) NaCl. 16S rRNA gene sequence-based phylogenetic analysis revealed that strain H23T48T was closely related to the genus Flaviflexus, with 97.0 and 96.7 % sequence similarities to Flaviflexus salsibiostraticola EBR4-1-2T and Flaviflexus huanghaiensis H5T, respectively. Strain H23T48T possessed MK-9(H4) as the major menaquinone and C16 : 0 (42.4 %), C18 : 1 ω9c (31.3 %) and C14 : 0 (17.7 %) as the major cellular fatty acids. The polar lipids included phosphatidylglycerol, two unidentified lipids, six unidentified phospholipids and two unidentified glycophospholipids. The amino acid composition of the cell-wall peptidoglycan was l-alanine, l-lysine, d-glutamic acid, l-aspartic acid and glycine. The genomic G+C content of strain H23T48T is 59.5 mol% and the average nucleotide identity value between H23T48T and F. salsibiostraticola KCT C33148T (=EBR4-1-2T) is 75.5 %. Based on the obtained data, strain H23T48T represents a novel species of the genus Flaviflexus, for which the name Flaviflexus ciconiae sp. nov. is proposed. The type strain is H23T48T (=KCTC 49253T=JCM 33282T).

Jeotgalibaca ciconiae sp. nov., isolated from the faeces of an Oriental stork.

A novel, Gram-stain-positive, non-spore-forming, facultatively anaerobic bacterium, designated strain H21T32T, was isolated from the faeces of an Oriental stork, Ciconia boyciana. Cells formed cocci grouped in pairs, tetrads or conglomerates, and colonies on solid medium were pale yellow. Strain H21T32T belonged to the genus Jeotgalibaca, family Carnobacteriaceae, order Lactobacillales and class Bacilli. The 16S rRNA gene sequences of the strain showed 97.06-97.34, 96.17-96.31 and 95.93-96.07 % similarity to the type strains of Jeotgalibaca arthritidis, J. porci and J. dankookensis, respectively. The strain grew at 10-37 °C (optimum temperature: 30 °C), with 0-7 % (w/v) NaCl (optimum salinity: 0.5 %) and at pH 7-9 (optimum pH: 8). The main cellular fatty acids were C16 : 1 ω9c, C18 : 1 ω9c and C16 : 0. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. Respiratory quinones were not detected. Sugar components of the peptidoglycan were rhamnose, ribose and glucose. Amino acid components of the cell wall were l-alanine, d-glucose, l-lysine, glycine and aspartic acid. The DNA G+C content of the strain was 37.1 mol%. Average nucleotide identity between strain H21T32T and J. arthritidis CECT 9157T was 77.02 %, confirming that strain H21T32T represents a novel species of the genus Jeotgalibaca, for which the name Jeotgalibaca ciconiae sp. nov. is proposed. The type strain is H21T32T (=KCTC 33991T=JCM 33222T).

Tabrizicola piscis sp. nov., isolated from the intestinal tract of a Korean indigenous freshwater fish, Acheilognathus koreensis.

A novel Gram-negative, obligately aerobic, rod-shaped and non-motile bacterium, designated strain K13M18T, was isolated from the intestinal tract of a Korean indigenous fish, oily bitterling (Acheilognathus koreensis). Strain K13M18T formed creamy-pink colonies on a marine agar plate. Results of phylogenetic analysis based on the 16S rRNA gene sequence similarity indicated that strain K13M18T was most closely related to Tabrizicola sediminis DRYC-M-16T, sharing 97.62 % similarity with that strain. Strain K13M18T belonged to the genus Tabrizicola, which formed a cluster with Tabrizicola aquatica RCRI19T, Tabrizicola fusiformis SY72T, Tabrizicola sediminis DRYC-M-16T and Tabrizicola alkalilacus DJCT in a phylogenetic tree based on the 16S rRNA gene sequences. Strain K13M18T grown optimally in 0 % (w/v) NaCl, at pH 7 and 30 °C, in a marine broth medium. The predominant cellular fatty acids were C18 : 1 ω7c and C18 : 1 ω6c. The major respiratory isoprenoid quinone was ubiquinone Q-10. Polar lipids of strain K13M18T contained phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, diphosphatidylglycerol, six unidentified aminophospholipids, one unidentified aminolipid and an unidentified lipid. Based on genome sequencing, the DNA G+C content of strain K13M18T was 64.08 mol %, with an average nucleotide identity value, calculated by a comparative genomic analysis of strains K13M18T and T. sediminis DRYC-M-16T, of 74.82 %. Based on the phylogenetic, genotypic, and phenotypic information, strain K13M18T is proposed to be a novel species of the genus Tabrizicola. The type strain is K13M18T (=KCTC 62659T=JCM 33230T).

Flammeovirga pectinis sp. nov., isolated from the gut of the Korean scallop, Patinopecten yessoensis.

A novel Gram-stain-negative, aerobic, rod-shaped, reddish-orange-coloured, gliding bacterial strain, designated L12M1T, was isolated from the gut of the Korean scallop, Patinopecten yessoensis. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain L12M1T formed a monophyletic clade with the strains in the genus Flammeovirga and showed highest 16S rRNA gene sequence similarity to Flammeovirga kamogawensis YS10T (98.66 %). The major cellular fatty acids of strain L12M1T were iso-C15 : 0 and C20 : 4ω6,9,12,15c. The predominant isoprenoid quinone was MK-7. The major polyamines were spermidine, cadaverine and the minor polyamine was putrescine. The DNA G+C content was 32.1 mol%. The phylogenetic, phenotypic, biochemical, chemotaxonomic and genotypic results indicated that strain L12M1T represents a novel species of the genus Flammeovirga, for which the name Flammeovirga pectinis sp. nov. is proposed. The type strain is L12M1T (=KCTC 62750T=JCM 33169T).

Pseudorhodobacter turbinis sp. nov., isolated from the gut of the Korean turban shell, Turbo cornutus.

A novel Gram-stain-negative, coccus-shaped, aerobic and motile bacterial strain, designated S12M18T, was isolated from the gut of the Korean turban shell, Turbo cornutus. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S12M18T belonged to the genus Pseudorhodobacter and had the highest 16S rRNA gene sequence similarity twith Pseudorhodobacter aquimaris HDW-19T (98.63 %). The phylogenomic tree congruently verified that strain S12M18T occupies a taxonomic position within the genus Pseudorhodobacter. The OrthoANIu value between strain S12M18T and P. aquimaris HDW-19T was 87.22 %. The major cellular fatty acid of strain S12M18T was summed feature 8 (C18 : 1 ω7c or C18 : 1 ω6c). The major components of the polar lipids were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The predominant isoprenoid quinone was Q-10. The DNA G＋C content was 57.8 mol%. The polyphasic analyses indicated that strain S12M18T represents a novel species of the genus Pseudorhodobacter, for which the name Pseudorhodobacter turbinis sp. nov. is proposed. The type strain is S12M18T (=KCTC 62742T=JCM 33168T).

Iodobacter ciconiae sp. nov., a bacterium isolated from feces of oriental stork, Ciconia boyciana.

A novel Gram-stain-negative, facultatively anaerobic, non-motile, non-violet-pigmented, rod-shaped bacterium, designated strain H11R3T, was isolated from the feces of Oriental stork, Ciconia boyciana, collected from Seoul Grand Park Zoo, Republic of Korea. Phylogenetic analysis of the 16S rRNA gene sequence revealed that H11R3T formed a monophyletic clade with Iodobacter fluviatilisDSM 3764T, Iodobacter arcticusDSM 100243T, and Iodobacter limnosediminisDSM 103822T, with sequence similarities of 98.8, 98.6 and 98.4 %, respectively. H11R3T grew optimally at 15 °C, pH 8, with 0.5 % (w/v) NaCl. The predominant isoprenoid quinone was ubiquinone-8 (Q-8), and polar lipids included phosphatidylethanolamine, three unidentified lipids, four unidentified phospholipids, and two unidentified aminophospholipids. The major fatty acids were summed feature 3 and C16 : 0, and the DNA G+C content of the genome is 48.0 mol%. The average nucleotide identity (ANI) value between strains H11R3T and I. fluviatilis NCTC 11159T (=DSM 3764T) is 83.7 %. On the basis of phenotypic, genotypic, phylogenetic and chemotaxonomic characteristics, strain H11R3T represents a novel species of the genus Iodobacter for which the name Iodobacterciconiae sp. nov. is proposed. The type strain is H11R3T (=KCTC 62666T=JCM 33283T).

Undibacterium piscinae sp. nov., isolated from Korean shiner intestine.

A novel Gram-stain-negative, non-spore-forming, obligate aerobic, motile, rod-shaped, and flagellated bacterium, designated S11R28T, was isolated from the intestinal tract of a Korean shiner, Coreoleuciscus splendidus. Based on 16S rRNA gene sequences, strain S11R28T was identified as member of the genus Undibacterium in class Betaproteobacteria, and was closely related to Undibacterium parvum DSM 23061T (98.49 %). The isolate grew at 4-25 °C, pH 6-9, with 0 % (w/v) NaCl, and grew optimally at 20 °C, pH 8, in the absence of NaCl. The main cellular fatty acids were C16 : 0 and summed features 3 (C16 : 1ω7c and/or C16 : 1ω6c). The strain possessed diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as predominant polar lipids, and ubiquinone Q-8 as a respiratory quinone. The polyamine profile composed of 2-hydroxyputrescine, spermidine, putrescine, and benzoic acid. A genomic DNA G+C content was 51.4 mol%. The average nucleotide identity between strains S11R28T and U. parvum DSM 23061T was 78.66 %. Thus, Undibacterium piscinae can be considered a novel species within the genus Undibacterium with the type strain S11R28T (=KCTC 62668T=JCM 33224T).

Indium Zinc Oxide Thin-Film Transistors with Ultraviolet Post-Annealing Treatment.

Ultraviolet treatment (UV) light was performed for indium zinc oxide thin-film transistors (TFTs) for different time so as to study the effects of post-annealing on electrical characteristic of TFTs. Electrical characteristic results proved that the value of high mobility after UV post-annealing process (2 mW/cm². for 30 s was obviously enhanced, and it had an acceptable on/off ratio, reasonable threshold voltage, and subthreshold swing. Among them, the value of the electronic mobility is 2.41 cm²/Vs, the threshold voltage value is 8.31 V, the on/off current ratio value is 2×2 × 105, and the subthreshold swing value is 1.13 V/dec.

Capacitance-Voltage Characteristics Analysis of Indium Zinc Oxide Thin Film Transistors Based Ultraviolet Light Irradiation.

The mechanism of solution-processed indium zinc oxide (IZO) thin film transistors (TFTs) made by simultaneous spin coating and ultraviolet (UV) light irradiation was investigated by capacitance-voltage (C-V) measurement. The application of UV light on the IZO TFTs was found to improve the thin film surface structure, and pledge to receive low degree of roughness. Meanwhile, electrical characteristics indicated that the TFT prepared at the UV light irradiation with 90 s exhibits the best performance with field-effect mobility 5.6 cm²/Vs, threshold voltage ═ -0.13 V, subthreshold gate swing 0.64 V/decade and on/off ratio ═ 1.7 × 106. In the C-V contrastive analysis with different UV light irradiation time by 60 s and 90 s, the frequency was varied from 100 Hz to 10 kHz to investigate low as well as high frequency C-V.

Imaging robust microglial activation after lipopolysaccharide administration in humans with PET.

Neuroinflammation is associated with a broad spectrum of neurodegenerative and psychiatric diseases. The core process in neuroinflammation is activation of microglia, the innate immune cells of the brain. We measured the neuroinflammatory response produced by a systemic administration of the Escherichia coli lipopolysaccharide (LPS; also called endotoxin) in humans with the positron emission tomography (PET) radiotracer [11C]PBR28, which binds to translocator protein, a molecular marker that is up-regulated by microglial activation. In addition, inflammatory cytokines in serum and sickness behavior profiles were measured before and after LPS administration to relate brain microglial activation with systemic inflammation and behavior. Eight healthy male subjects each had two 120-min [11C]PBR28 PET scans in 1 d, before and after an LPS challenge. LPS (1.0 ng/kg, i.v.) was administered 180 min before the second [11C]PBR28 scan. LPS administration significantly increased [11C]PBR28 binding 30-60%, demonstrating microglial activation throughout the brain. This increase was accompanied by an increase in blood levels of inflammatory cytokines, vital sign changes, and sickness symptoms, well-established consequences of LPS administration. To our knowledge, this is the first demonstration in humans that a systemic LPS challenge induces robust increases in microglial activation in the brain. This imaging paradigm to measure brain microglial activation with [11C]PBR28 PET provides an approach to test new medications in humans for their putative antiinflammatory effects.

Vibrio Phage KVP40 Encodes a Functional NAD+ Salvage Pathway.

The genome of T4-type Vibrio bacteriophage KVP40 has five genes predicted to encode proteins of pyridine nucleotide metabolism, of which two, nadV and natV, would suffice for an NAD+ salvage pathway. NadV is an apparent nicotinamide phosphoribosyltransferase (NAmPRTase), and NatV is an apparent bifunctional nicotinamide mononucleotide adenylyltransferase (NMNATase) and nicotinamide-adenine dinucleotide pyrophosphatase (Nudix hydrolase). Genes encoding the predicted salvage pathway were cloned and expressed in Escherichia coli, the proteins were purified, and their enzymatic properties were examined. KVP40 NadV NAmPRTase is active in vitro, and a clone complements a Salmonella mutant defective in both the bacterial de novo and salvage pathways. Similar to other NAmPRTases, the KVP40 enzyme displayed ATPase activity indicative of energy coupling in the reaction mechanism. The NatV NMNATase activity was measured in a coupled reaction system demonstrating NAD+ biosynthesis from nicotinamide, phosphoribosyl pyrophosphate, and ATP. The NatV Nudix hydrolase domain was also shown to be active, with preferred substrates of ADP-ribose, NAD+, and NADH. Expression analysis using reverse transcription-quantitative PCR (qRT-PCR) and enzyme assays of infected Vibrio parahaemolyticus cells demonstrated nadV and natV transcription during the early and delayed-early periods of infection when other KVP40 genes of nucleotide precursor metabolism are expressed. The distribution and phylogeny of NadV and NatV proteins among several large double-stranded DNA (dsDNA) myophages, and also those from some very large siphophages, suggest broad relevance of pyridine nucleotide scavenging in virus-infected cells. NAD+ biosynthesis presents another important metabolic resource control point by large, rapidly replicating dsDNA bacteriophages.IMPORTANCE T4-type bacteriophages enhance DNA precursor synthesis through reductive reactions that use NADH/NADPH as the electron donor and NAD+ for ADP-ribosylation of proteins involved in transcribing and translating the phage genome. We show here that phage KVP40 encodes a functional pyridine nucleotide scavenging pathway that is expressed during the metabolic period of the infection cycle. The pathway is conserved in other large, dsDNA phages in which the two genes, nadV and natV, share an evolutionary history in their respective phage-host group.

(11)C-PBR28 imaging in multiple sclerosis patients and healthy controls: test-retest reproducibility and focal visualization of active white matter areas.

PURPOSE: Activated microglia play a key role in inflammatory demyelinating injury in multiple sclerosis (MS). Microglial activation can be measured in vivo using a positron emission tomography (PET) ligand (11)C-PBR28. We evaluated the test-retest variability (TRV) and lesion detectability of (11)C-PBR28 binding in MS subjects and healthy controls (HCs) with high-resolution PET. METHODS: Four clinically and radiologically stable relapsing-remitting MS subjects (age 41 ± 7 years, two men/two women) and four HCs (age 42 ± 8 years, 2 two men/two women), matched for translocator protein genotype [two high- and two medium-affinity binders according to DNA polymorphism (rs6971) in each group], were studied for TRV. Another MS subject (age 41 years, male) with clinical and radiological activity was studied for lesion detectability. Dynamic data were acquired over 120 min after injection of 634 ± 101 MBq (11)C-PBR28. For the TRV study, subjects were scanned twice, on average 1.4 weeks apart. Volume of distribution (V T) derived from multilinear analysis (MA1) modeling (t* = 30 min, using arterial input data) was the main outcome measure. RESULTS: Mean test V T values (ml cm(-3)) were 3.9 ± 1.4 in the whole brain gray matter (GM), 3.6 ± 1.2 in the whole brain white matter (WM) or normal-appearing white matter (NAWM), and 3.3 ± 0.6 in MS WM lesions; mean retest V T values were 3.7 ± 1.0 in GM, 3.3 ± 0.9 in WM/NAWM, and 3.3 ± 0.7 in MS lesions. Test-retest results showed a mean absolute TRV ranging from 7 to 9 % across GM, WM/NAWM, and MS lesions. High-affinity binders demonstrated 30 % higher V T than medium-affinity binders in GM. Focal (11)C-PBR28 uptake was detected in two enhancing lesions of the active MS patient. CONCLUSION: High-resolution (11)C-PBR28 PET can visualize focal areas where microglial activation is known to be present and has good test-retest reproducibility in the human brain. (11)C-PBR28 PET is likely to be valuable for monitoring both MS disease evolution and response to therapeutic strategies that target microglial activation.

Reinforcing Effects of Poly(D-Lactide)-g-Multiwall Carbon Nanotubes on Polylactide Nanocomposites.

Polylactide (PLA) nanocomposites with multi-walled carbon nanotubes (MWNTs) grafted with poly(L-lactide) or poly(D-lactide) were prepared by solution casting, and their thermal and mechanical properties were evaluated. MWNTs containing hydroxyl groups were treated by ring-opening polymerization of either L-lactide or D-lactide. Fourier transform infrared spectroscopy confirmed that the MWNT surfaces had been modified by the PLLA or PDLA chains. The thermal properties were measured by differential scanning calorimetry and thermogravimetric analysis. The mechanical properties were examined using a universal testing machine. The morphology of the fractured surfaces of the PLA nanocomposites was observed by scanning electron microscopy and transmission electron microscopy. PDLA-g-MWNTs were dispersed more uniformly compared to PLLA-g-MWNTs in the PLA matrix. The incorporation of PDLA-g-MWNTs greatly improved the tensile strength of the nanocomposites regardless of the contents. Thermal analysis revealed different characteristics at specific composites depending on the type of modification.