Biophoton emission

The phenomenon of ultraweak photon emission from living systems was further investigated in order to elucidate the physical properties of this radiation and its possible source. We obtained evidence that the light has a high degree of coherence because of (1) its photon count statistics, (2) its spectral distribution, (3) its decay behavior after exposure to light illumination, and (4) its transparency through optically thick materials. Moroever, DNA is apparently at least an important source, since conformational changes induced with ethidium bromide in vivo are clearly reflected by changes of the photon emission of cells. The physical properties of the radiation are described, taking DNA as an exciplex laser system, where a stable state can be reached far from thermal equilibrium at threshold.     

Physiology as a caste-defining feature

Division of labour is a key factor in the ecological success of social insects. Groups of individuals specializing on a particular behaviour are known as castes and are usually distinguished by morphology or age. Physiology plays a key role in both these types of caste, in either the developmental physiology which determines morphology, or the temporal changes in physiology over an insect’s life. Physiological correlates of morphological or temporal caste include differences in gland structure, secretory products, leanness, neuroanatomy and neurochemistry. However, purely physiological castes could also occur. Physiological castes are discrete groups of same-age same-size individuals with particular physiological competencies, or groups of individuals with similar physiology crossing age or size groups. A stable physiological caste occurs in the monomorphic Pharaoh’s ant, where some ants can detect old pheromone trails and retain this specialization over time. These ants differ physiologically from other workers, and the differences arise before eclosion. More temporary physiological castes occur in the ant Ectatomma where brood care specialists have more developed ovarioles than other same-aged workers, and in the honeybee where nurses, wax-workers and soldiers all differ physiologically from same-aged nestmates. Physiology is an important aspect of caste, not only in its contribution to age-related and morphological castes, but also in its own right as a caste grouping factor. While age and morphological differences make caste structures accessible for study, more cryptic physiological castes may play just as important a role in division of labour. Received 19 December 2007; revised 24 July and 18 September 2008; accepted 19 September 2008.     

A Study on Size Hierachies of Individuals OF Elymus nutans Population under Different Densities

The size hierachies of a perennial grass population, Elymus nutans, which distributes throghout the subalpine meadow has been studied. A two-year experiment was designed to include seven treatments of different densities and measurements of inequality and distributions of individual mass of the population at different harvest time from 1987 to 1989. Individual mass under each of the seven treatments did not reveal a normal or lognormal distribution. No skewness values smaller than 0.5 occurred in our 48 sets of data, which implied that the distribution of the indiciduals of E. nutans population at any density skewed to small individuals. This result emphasized an evidence that there were differences between perennial grasses and annual grasses in responding to intraspecies competition. Size inequality did not increase with increasing population densities. This however, was not in concert with the results of experiments from others. Size inequality, on the other hand, was wore prominent in the period of vegetative growth than in the period of maturity.     

The effects of ovariectomy and strech on the regulatory profile and activity of the uterus

Following ovariectomy of five New Zealand white rabbits at day 25 of pregnancy, the intrauterine pressure (IUP) and uterine progesterone (P) and prostaglandin (PG) levels were measured sequentially at days 25, 26 and 27. At day 25, when the uterine P and PGE and PGF were high, massive intrauterine treatment with 500 μg PGF2α provoked only a sustained contracture on which only low level oscillation in IUP was superimposed. At day 26, when the P levels had decreased significantly (P<0.001) and the PG levels had not changed significantly, 50 μg PGF2α significantly increased cyclic IUP as compared with the day 25 value (P<0.001). At day 27, when the P levels decreased further, as little as 5 μg PGF2α provoked still higher cyclic IUP, in spite of a significant reduction in PG levels (P<0.05).Stretching the uterus of six post partum and six 26 days pregnant rabbits (after removing the uterine contents) significantly increased the uterine PGF levels (P<0.001). However, stretch increased only cyclic IUP of the post partum uterus and was without effect on the pregnant uterus, which still had high P levels. These results indicate that the myometrium activated by exogenous PG or stretch, regardless of whether the uterine PG levels increase, remain unchanged or even moderately decrease, provided that the uterine P levels are reduced to a critical value.     

Interconversion and disproportionation reaction among cyclodextrin homologues in an aqueous two-phase-forming solution

Interconversion reactions of cyclodextrin glycosyltransferase (CGTase) among cyclodextrin (CD) homologues were experimentally investigated using each CD as a substrate in an aqueous, two-phase-forming polymer solution of dextran and polyethylene glycol. Degradation rate of -CD was highest and that of -CD was lowest among -, - and -CD with Bacillus macerans CGTase. Degradation of each CD was accelerated with dextran, while decelerated with polyethylene glycol.     

Remarkable synergies between baicalein and tetracycline, and baicalein and beta-lactams against methicillin-resistant Staphylococcus aureus

During the screening of compounds that potentiate the effect of antimicrobial agents against methicillin-resistant Staphylococcus aureus(MRSA), we found that an extract of thyme (Thymus vulgaris L) leaves greatly reduced the minimum inhibitory concentration (MIC) of tetracycline against MRSA. We isolated the effective compound and identified it as baicalein (5, 6, 7-trihydroxyflavone). One of the clinically isolated MRSA strains possessed tetK, a gene encoding active efflux pump for tetracycline. We examined the effect of baicalein on the efflux of tetracycline, using Escherichia coli KAM32/pTZ1252 carrying the tetK. The E. coli KAM32/pTZ1252 showed 8 to 16 times higher MIC than E. coli KAM32. We observed strong inhibition of transport of tetracycline by baicalein with membrane vesicles prepared from E. coli KAM32/pTZ1252. Baicalein also showed synergy with tetracycline in a MRSA strain that doesn't possess tetK, or with beta-lactams. Thus, mechanisms of the synergies seem to be versatile.     

The first potassium channel toxin from the venom of the Iranian scorpion Odonthobuthus doriae

The very first member of K(+) channels toxins from the venom of the Iranian scorpion Odonthobuthus doriae (OdK1) was purified, sequenced and characterized physiologically. OdK1 has 29 amino acids, six conserved cysteines and a pI value of 4.95. Based on multiple sequence alignments, OdK1 was classified as alpha-KTx 8.5. The pharmacological effects of OdK1 were studied on six different cloned K(+) channels (vertebrate Kv1.1-Kv1.5 and Shaker IR) expressed in Xenopus laevis oocytes. Interestingly, OdK1 selectively inhibited the currents through Kv1.2 channels with an IC50 value of 183+/-3 nM but did not affect any of the other channels.     

早熟金柚果皮挥发油的提取及GC-MS分析

采用水蒸气蒸馏法提取早熟金柚果皮挥发油,通过正交实验优选获得早熟金柚果皮挥发油提取的工艺参数,结果表明：早熟金柚果皮挥发油的最佳提取工艺是将柚皮粉碎60 s,加水5倍,提取6 h。采用GC-MS联用技术对早熟金柚果皮挥发油的化学成分进行分离鉴定,共分离出44个峰,鉴定出了其中的25种化合物,占峰面积的98.43%。用面积归一化法测定了各个组分的相对百分含量,其主要成分有柠檬烯（65.82%）、β-月桂烯（25.52%）、4-侧柏烯（1.78%）、紫苏烯（0.44%）、氧化芳樟醇（0.42%）。