DUDRESNAYA PATULA SP. NOV., AN UNUSUAL DEEP-WATER RED ALGA FROM FLORIDA1

Dudresnaya patula sp. nov. is described from 30–60 m depth on the east coast of Florida. The plant grows to a height of at least 10 cm, has flattened axes and main branches to 2 cm wide and 3 mm thick, and has unusually long female reproductive branches. The new species is compared to other Dudresnaya species in habitat, vegetative structure, and reproductive morphology.     

Comparative analysis of the mechanisms of attack and defense among higher brain animals

Many studies have investigated different mechanisms of attack and defense in different species of higher brain animals including cats, rats, rodents, mice, and even in some bird species. However, detailed comparative analysis has not been carried out to understand the major similarities in the mechanisms of attack and defense across the different species of vertebrates. Although there are differences, there are also significant similarities as well, which warrant comparative assessment. By considering ethological ideas associated with the motivational defense system, we investigated the motor patterns of attack and defense in cats and rats, using the “resident-intruder” experimental paradigm. Our results reveal specific similarities and differences in the motor patterns of attack and defense in rats and cats. We discuss comparatively the mechanisms of attack and defense across different species of vertebrates, focusing on motor patterns, neuromodulating factors, brains neural substrates, and circuitry.     

Association of 1 hydroxypyrene glucuronide in human urine with cigarette smoking and broiled or roasted meat consumption

Humans are exposed to polycyclic aromatic hydrocarbons PAHs from various occupational, dietary, environmental and medicinal sources. We measured 1 hydroxypyrene glucuronide 1 OHP gluc concentration in urines from male non smokers n = 50, smokers of blond tobacco n = 31, smokers of black tobacco n = 16, and pipe smokers n = 3 . Immunoaffinity chromatography was used as a preparative step and synchronous fluorescence spectroscopy as the quantitation method. The concentration of 1 OHP gluc in urine from smokers mean SE: 1.04 0.13 pmol ml-1 urine was significantly higher than in urine from non smokers 0.55 0.05 pmol ml-1 urine by the Wilcoxon rank sum test non smokers versus all smokers, p = 0.001; vs black tobacco smokers, p = 0.001; vs blond tobacco smokers, p = 0.007 . Urinary 1 OHP gluc concentration among subjects who had consumed roasted, grilled or broiled meat within the past 24 h was elevated compared with those who had not p = 0.025 . Multiple linear regression showed significant associations of urinary 1 OHP gluc with number of cigarettes smoked p = 0.002 and consumption of roasted, grilled or broiled meat p = 0.028 . Systemic CYP1A2 activity estimated by caffeine metabolism was significantly correlated with urinary 1 OHP gluc concentration. However, this association was probably due to cigarette smoking, since adjusting for cigarette smoking by multiple linear regression made the association between urinary 1 OHP gluc and CYP1A2 phenotype non significant. These results further support the use of urinary 1 OHP gluc as a biomarker of recent pyrene exposure through inhalation or diet.     

Continuous assessment of metabolic activity of mitochondria using resonance Raman microspectroscopy

Dysfunctional mitochondrial activity can lead to a variety of different diseases. As such, there exists a need to quantify changes in mitochondria function as it relates to these specific diseased states. Here, we present the use of resonance Raman (RR) spectroscopy as a tool to determine changes in isolated mitochondrial activity. RR spectroscopy, using 532 nm as the excitation source, specifically provides information on the reduction and oxidation (RedOx) state of cytochrome c, which is determined by the activity of protein complexes in the electron transport chain (ETC). In this model, injection of the substrate succinate into the mitochondrial sample is used to drive the ETC, which causes a subsequent change in cytochrome c RedOx state. This change in RedOx state is tracked by RR spectroscopy. This tool gives real-time information on the rise and fall of the amount of reduced cytochrome c within the mitochondrial sample, providing a method for rapid assessment of mitochondrial metabolism that has broad applications in both basic science and medical research.     

Messenger RNA 5′ NAD+ Capping Is a Dynamic Regulatory Epitranscriptome Mark That Is Required for Proper Response to Abscisic Acid in Arabidopsis

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Fluorescent-labeled crosslinks in collagen: Pyrenebutyrylhydrazine

The aldehydes present in acid-soluble type I collagen react with pyrenebutyrylhydrazine to form various types of complexes under different reaction conditions. These complexes exhibit one or more of three different pyrene fluorescence bands: monomer, excimer, and aggregate fluorescence. Collagen, whose aldehydes have been reduced with NaBH₄, does not react with this fluorescent hydrazine, confirming that the hydrazine reacts specifically with aldehyde groups to form hydrazones. The absence of a reaction with pepsin-treated collagen also shows that the fluorescent labels are primarily in the nonhelical terminal telopeptides. Upon dialysis, the pyrene label bound to a saturated aldehyde in an α-chain is lost; whereas that bound to an unsaturated aldehyde remains on the protein. The pyrene monomer fluorescence in the β-chain of old collagen is stronger than that of young collagen. The formation of the pyrene excimer fluorescence implies the proximity of two pyrene molecules, probably attached to two adjacent aldehydes. Upon changing from acidic to neutral pH, both excimer and aggregate fluorescence bands disappear within a few seconds, revealing a very rapid alteration at the telopeptides.