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Two-dimensional nanomaterials play a critical role in biology (e.g., lipid bilayers) and electronics (e.g., graphene) but are difficult to directly synthesize with a high level of precision. Peptoid nanosheet bilayers are a versatile synthetic platform for constructing multifunctional, precisely ordered two-dimensional nanostructures. Here we show that nanosheet formation occurs through an unusual monolayer intermediate at the air-water interface. Lateral compression of a self-assembled peptoid monolayer beyond a critical collapse pressure results in the irreversible production of nanosheets. An unusual thermodynamic cycle is employed on a preparative scale, where mechanical energy is used to buckle an intermediate monolayer into a more stable nanosheet. Detailed physical studies of the monolayer-compression mechanism revealed a simple preparative technique to produce nanosheets in 95% overall yield by cyclical monolayer compressions in a rotating closed vial. Compression of monolayers into stable, free-floating products may be a general and preparative approach to access 2D nanomaterials., (© 2011 American Chemical Society)

This study evaluates the presence, location and production source of tetrodotoxin (TTX) in two species of pufferfish, Diodon histrix and Arothron hispidus, common to Hawaiian waters. Organs from each fish were analysed for TTX and used to isolate bacteria for evaluation of possible TTX production. Comparative analyses of extracts of fish and bacterial culture media were performed with liquid chromatography-mass spectrometry (LC-MS) and a sodium channel specific bioassay. Bacterial cultivation experiments were performed in two different growth media and bacteria were identified through sequence homology of the 16S rRNA gene. Forty-two and forty-seven distinct strains were cultivated from D. histrix and A. hispidus, respectively. However, no commonality was found between the populations of bacteria isolated from the two fish. TTX was detected only in A. hispidus and was present in the flesh, pectoral fin and kidneys, as well as the skin slime. Sixteen of the forty-seven bacterial species isolated from A. hispidus were cultivated for further evaluation of TTX production. Among these sixteen bacterial species, Vibrio harveyi strains isolated from the skin slime and kidneys of A. hispidus were found to produce TTX, being the source of TTX produced in the pufferfish.

A Gram-negative, non-flagellated, rod-shaped bacterium, designated strain P2K6(T), was isolated from the kidneys of a pufferfish (Arothron hispidus) caught off the coast of Kaneohe Bay, O'ahu, Hawai'i. The strain formed yellowish colonies when grown on marine agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain P2K6(T) was related most closely to members of the genus Chryseobacterium. Levels of 16S rRNA gene sequence similarity between strain P2K6(T) and the type strains of recognized species of the genus Chryseobacterium were 94-96.6%, suggesting that the strain represents a novel species within this genus. The DNA G+C content of strain P2K6(T) was 36.5 mol%, the dominant fatty acids were iso-C(15:0) (35.3%) and iso-C(17:0) 3-OH (14.9%), and the most abundant quinone was menaquinone MK6. On the basis of the data from this polyphasic study, it is suggested that strain P2K6(T) represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium arothri sp. nov. is proposed. The type strain is P2K6(T) (=CIP 109575(T)=DSM 19326(T)).

A novel species, strain P2S11T, was isolated from the mucus of a puffer fish caught off the coast of Kaneohe Bay, O'ahu, Hawai'i. A phylogenetic analysis based on 16S rRNA gene sequences showed that the novel strain was most closely related to Ferrimonas marina DSM 16917T and Ferrimonas balearica DSM 9799T with 93.5% and 82.9% sequence similarities, respectively, which established the novel strain as belonging to the genus Ferrimonas. The strain formed off-white coloured colonies on marine agar and cells were Gram-negative, non-motile rods. H2S was produced when strain P2S11T was grown on TSI medium with added salt. Strain P2S11T had a DNA G+C content of 54.9 mol% and the dominant fatty acids were C16:1omega9c, C16:0 and C17:1omega8c. On the basis of this polyphasic study, strain P2S11T (=ATCC BAA-1480T=DSM 18821T) represents a novel species of the genus Ferrimonas, for which the name Ferrimonas senticii sp. nov. is proposed.

Nineteen bacterial strains were isolated from petroleum-contaminated soil in Hilo, HI, and characterized by two different spray-plated methods, turbidity test in liquid medium, and 16S rRNA gene sequence analysis. Analysis of the soil showed 13 polycyclic aromatic hydrocarbons (PAHs) in a range from 0.6 to 30 mg/kg of dry weight each and 12 PAH metabolites. Five distinct bacterial strains (C3, C4, P1-1, JS14, and JS19b1) selected from preliminary plating and turbidity tests were further tested for PAH degradation through single PAH degradation assay. Strains C3, C4, and P1-1 degraded phenanthrene (40 mg/L) completely during 7 days of incubation. Strain JS14 degraded fluoranthene (40 mg/L) completely during 10 days of incubation. Strain JS19b1 degraded 100% of phenanthrene (40 mg/L) in 7 days, 77% of fluorene (40 mg/L) in 14 days, 97% of fluoranthene (40 mg/L) in 10 days, and 100% of pyrene (40 mg/L) in 14 days. Turbidity tests showed that strains P1-1, JS14, and JS19b1 utilized several organophosphorus pesticides as growth substrate. P1-1 can degrade carbofenothion, chlorfenvinphos, diazinon, fonofos, and pirimiphos-methyl. JS14 can transform chlorfenvinphos and diazinon. JS19b1 can break down diazinon, pirimiphos-methyl, and temephos.

An aerobic, mesophilic bacterium, strain JA40T, was isolated from soil contaminated with polycyclic aromatic hydrocarbons and polychlorinated biphenyls collected from Johnston Atoll in the North Pacific Ocean. The strain formed yellow-pigmented colonies on heterotrophic media. The cells were Gram-negative, non-motile, non-sporulating rods. The strain reduced nitrite to nitrous oxide, the DNA G+C content was 64 mol% and the dominant fatty acids were 15 : 0 iso, 17 : 1 iso cis7 and 11 : 0 iso 3-OH. DNA sequencing of 1457 nt of the 16S rRNA gene established that JA40T belongs in the genus Pseudoxanthomonas within the Xanthomonadaceae branch of the Gammaproteobacteria. Strain JA40T can be differentiated from other mesophilic species in the genus on the basis of its physiological and biochemical characteristics and distinctive fatty acid profile. Thus strain JA40T (=ATCC BAA-1031T=CIP 108476T) is the type strain of a novel species of the genus Pseudoxanthomonas, for which the name Pseudoxanthomonas kalamensis sp. nov. is proposed.

Introduction: Breast cancer has the second highest incidence and is the first cause of death by cancer among Brazilian women. Under the physician's perspective chemotherapy should be indicated according to the risk benefit ratio in each case. However, from the Brazilian breast cancer patient's perspective this risk benefit ratio requires further classification., Objective: In patients with breast cancer who have already received chemotherapy evaluate the minimum benefit considered necessary for a renewed administration and learn which factors may influence this decision., Methods: we surveyed 53 patients comprising general, clinical and cancer related variables, as well as issues related to the minimal expected benefit which would induce the patient to agree to undergo chemotherapy., Results: 75% would accept to receive chemotherapy again even if it would not change their probability of relapse, 50% would accept chemotherapy again, even though it would not increase survival rates. Similarly, 81.54% would submit once more to chemotherapy even though it would not increase their probability of cure. Acceptance of a new chemotherapy treatment yielding minimal benefits correlated significantly with more age, with a lower educational level and with no previous administration of Adriamycin., Conclusion: Even with a minimal benefit, the majority of formerly treated breast cancer patients are willing to submit to another chemotherapy treatment.

Increased concentrations of angiotensin converting enzyme (ACE) were found in lung lavages from rabbits exposed to hyperoxia for 72 h and the concentrations of ACE were correlated with ratios of extravascular lung water to body weight (r = 0.69, p less than 0.05) and albumin concentrations in lung lavages (r = 0.89, p less than 0.01). In parallel studies, rabbits treated with nitrogen mustard in which granulocytopenia was maintained throughout the 72-h hyperoxic exposure period had less evidence of edematous lung injury and lower concentrations of ACE in their lung lavages than similarly treated rabbits in which granulocytopenia was not maintained. The results suggested that granulocytes contribute to acute edematous lung injury from hyperoxia and that ACE concentrations in lung lavages reflect this process.