Alarm Pheromone Processing in the Ant Brain: An Evolutionary Perspective

Social insects exhibit sophisticated communication by means of pheromones, one example of which is the use of alarm pheromones to alert nestmates for colony defense. We review recent advances in the understanding of the processing of alarm pheromone information in the ant brain. We found that information about formic acid and n-undecane, alarm pheromone components, is processed in a set of specific glomeruli in the antennal lobe of the ant Camponotus obscuripes. Alarm pheromone information is then transmitted, via projection neurons (PNs), to the lateral horn and the calyces of the mushroom body of the protocerebrum. In the lateral horn, we found a specific area where terminal boutons of alarm pheromone-sensitive PNs are more densely distributed than in the rest of the lateral horn. Some neurons in the protocerebrum responded specifically to formic acid or n-undecane and they may participate in the control of behavioral responses to each pheromone component. Other neurons, especially those originating from the mushroom body lobe, responded also to non-pheromonal odors and may play roles in integration of pheromonal and non-pheromonal signals. We found that a class of neurons receive inputs in the lateral horn and the mushroom body lobe and terminate in a variety of premotor areas. These neurons may participate in the control of aggressive behavior, which is sensitized by alarm pheromones and is triggered by non-pheromonal sensory stimuli associated with a potential enemy. We propose that the alarm pheromone processing system has evolved by differentiation of a part of general odor processing system

Experimental Demonstration of Adaptive Quantum State Estimation

The first experimental demonstration of an adaptive quantum state estimation (AQSE) is reported. The strong consistency and asymptotic efficiency of AQSE have been mathematically proven [ A. Fujiwara J. Phys. A 39 12489 (2006)]. In this Letter, the angle of linear polarization of single photons, the phase parameter between the right and the left circularly polarization, is estimated using AQSE, and the strong consistency and asymptotic efficiency are experimentally verified. AQSE will provide a general useful method in both quantum information processing and metrology.Comment: 5pages, 4figure

Grain Boundary Fracture of α Brass Bicrystals at an Intermediate Temperature Range

Deformation and grain boundary fracture behaviours of α brass bicrystals were examined. The results are summarized as follows : (1) The temperature dependence of the ductility of α brass bicrystals accompaning intergranular fracture is similar to that observed in α brass poly-crystals. (2) The transition from transgranular to intergranular fracture starts at about 470 K and again a transgranular fracture appears at about 770 K : i. e., the inter-granular fracture occurs in the temperature range of 470 to 770 K. It is note worthy that the lower transition temperature (470 K) corresponds to the onset of the inverse temperature dependence of yield stress. Also, the temperature at which the minimum value of ductility reveals coincides with that at which a peak in the yield stress appears. (3) Though the intercrystalline fracture accompanies the separation at the grain boundary plane macroscopically, it is a ductile fracture in the neighbourhood of grain boundary microscopically. Thus, apparent intergranular fracture seems to be caused by the coalescence of micro cleavage cracks along {111} planes, which are induced by the stress concentration due to dislocation pile-ups. (4) From those observations mentioned above, it is clear that the dynamic strain aging behaviour plays an important role in the intergranular fracture of α brass bicrystals

Stroke Status Evoked Adhesion Molecule Genetic Alterations in Astrocytes Isolated from Stroke-Prone Spontaneously Hypertensive Rats and the Apigenin Inhibition of Their Expression

We examined the possibility that the expression of adhesion molecules is regulated differently in cultured astrocytes from stroke-prone spontaneously hypertensive rats (SHRSP/IZM) rats than in those from Wistar Kyoto rats (WKY/IZM) by tumor necrosis factor-alpha (TNF-α) or hypoxia and reoxygenation (H/R) and the inhibitory effects of apigenin. It was found that the expression of vascular cell adhesion molecule-1 (VCAM-1) by TNF-α in astrocytes isolated from SHRSP/IZM was increased compared with that in WKY/IZM. The expression of monocyte chemotactic protein-1 (MCP-1) mRNA induced by H/R in SHRSP/IZM astrocytes was increased compared with that in normal oxygen concentrations. Apigenin strongly attenuated TNF-α-induced VCAM-1 mRNA and protein expression and suppressed the adhesion of U937 cells and SHRSP/IZM astrocytes. These results suggest that the expression levels of adhesion molecules during H/R affect disease outcome and can drive SHRSP/IZM to stroke. It is suggested that apigenin regulates adhesion molecule expression in reactive astrocytes during ischemia

Mammalian enzymes for preventing transcriptional errors caused by oxidative damage

8-Oxo-7,8-dihydroguanine (8-oxoGua) is produced in cells by reactive oxygen species normally formed during cellular metabolic processes. This oxidized base can pair with both adenine and cytosine, and thus the existence of this base in messenger RNA would cause translational errors. The MutT protein of Escherichia coli degrades 8-oxoGua-containing ribonucleoside di- and triphosphates to the monophosphate, thereby preventing the misincorporation of 8-oxoGua into RNA. Here, we show that for human the MutT-related proteins, NUDT5 and MTH1 have the ability to prevent translational errors caused by oxidative damage. The increase in the production of erroneous proteins by oxidative damage is 28-fold over the wild-type cells in E.coli mutT deficient cells. By the expression of NUDT5 or MTH1 in the cells, it is reduced to 1.4- or 1.2-fold, respectively. NUDT5 and MTH1 hydrolyze 8-oxoGDP to 8-oxoGMP with V(max)/K(m) values of 1.3 × 10(−3) and 1.7 × 10(−3), respectively, values which are considerably higher than those for its normal counterpart, GDP (0.1–0.5 × 10(−3)). MTH1, but not NUDT5, possesses an additional activity to degrade 8-oxoGTP to the monophosphate. These results indicate that the elimination of 8-oxoGua-containing ribonucleotides from the precursor pool is important to ensure accurate protein synthesis and that both NUDT5 and MTH1 are involved in this process in human cells

Clinical Study Clinical Characteristics of Nocardia Infection in Patients with Rheumatic Diseases

Although Nocardiosis has considerable recurrence and mortality rates, characteristics and risk factors of Nocardia infection have not been assessed in patients with rheumatic diseases. Here, we examined the characteristics and risk factors of Nocardia infection in rheumatic disease patients in our hospital. Ten rheumatic disease patients who developed Nocardia infection were identified by retrospectively reviewing the medical records. Possible predisposing factors for Nocardia infection were high-dose glucocorticoid treatment, concomitant use of immunosuppressants, preexisting pulmonary diseases, and diabetes mellitus. All patients had pulmonary Nocardiosis, and six of them had disseminated Nocardiosis when their pulmonary lesions were identified

Antibiotic prescription for outpatients with influenza and subsequent hospitalisation: a cohort study using insurance data

Background Whether prophylactic administration of antibiotics to patients with influenza reduces the hospitalisation risk is unknown. We aimed to examine the association between antibiotic prescription in outpatients with influenza infection and subsequent hospitalisation. Methods We conducted a cohort study using health insurance records of Japanese clinic and hospital visits between 2012 and 2016. Participants were outpatients (age, 0–74 years) with confirmed influenza infection who were prescribed anti-influenza medicine. The primary outcomes were the hospitalisation risk from all causes and pneumonia and the duration of hospitalisation due to pneumonia. Results We analysed 903,104 outpatient records with 2469 hospitalisations. The risk of hospitalisation was greater in outpatients prescribed anti-influenza medicine plus antibiotics (0.31% for all causes and 0.18% for pneumonia) than in those prescribed anti-influenza medicine only (0.27% and 0.17%, respectively). However, the risk of hospitalisation was significantly lower in patients prescribed peramivir and antibiotics than in those prescribed peramivir only. Patients who received add-on antibiotics had a significantly longer hospital stay (4.12 days) than those who received anti-influenza medicine only (3.77 days). In all age groups, the hospitalisation risk from pneumonia tended to be greater in those who received antibiotics than in those prescribed anti-influenza medicine only. However, among older patients (65–74 years), those provided add-on antibiotics had an average 5.24-day shorter hospitalisation due to pneumonia than those provided anti-influenza medicine only (not significant). Conclusions In outpatient cases of influenza, patients who are prescribed antibiotics added to antiviral medicines have a higher risk of hospitalisation and longer duration of hospitalisation due to pneumonia

The role of melatonin as an antioxidant in the follicle

Melatonin (N-acetyl-5-methoxytryptamine) is secreted during the dark hours at night by pineal gland, and it regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. It has been believed that melatonin regulates ovarian function by the regulation of gonadotropin release in the hypothalamus-pituitary gland axis via its specific receptors. In addition to the receptor mediated action, the discovery of melatonin as a direct free radical scavenger has greatly broadened the understanding of melatonin's mechanisms which benefit reproductive physiology. Higher concentrations of melatonin have been found in human preovulatory follicular fluid compared to serum, and there is growing evidence of the direct effects of melatonin on ovarian function especially oocyte maturation and embryo development. Many scientists have focused on the direct role of melatonin on oocyte maturation and embryo development as an anti-oxidant to reduce oxidative stress induced by reactive oxygen species, which are produced during ovulation process. The beneficial effects of melatonin administration on oocyte maturation and embryo development have been confirmed by in vitro and in vivo experiments in animals. This review also discusses the first application of melatonin to the clinical treatment of infertile women and confirms that melatonin administration reduces intrafollicular oxidative damage and increase fertilization rates. This review summarizes our recent works and new findings related to the reported beneficial effects of melatonin on reproductive physiology in its role as a reducer of oxidative stress, especially on oocyte maturation and embryo development