SIFamide and SIFamide Receptor Define a Novel Neuropeptide Signaling to Promote Sleep in Drosophila

SIFamide receptor (SIFR) is a Drosophila G protein-coupled receptor for the neuropeptide SIFamide (SIFa). Although the sequence and spatial expression of SIFa are evolutionarily conserved among insect species, the physiological function of SIFa/SIFR signaling remains elusive. Here, we provide genetic evidence that SIFa and SIFR promote sleep in Drosophila. Either genetic ablation of SIFa-expressing neurons in the pars intercerebralis (PI) or pan-neuronal depletion of SIFa expression shortened baseline sleep and reduced sleep-bout length, suggesting that it caused sleep fragmentation. Consistently, RNA interference-mediated knockdown of SIFR expression caused short sleep phenotypes as observed in SIFa-ablated or depleted flies. Using a panel of neuron-specific Gal4 drivers, we further mapped SIFR effects to subsets of PI neurons. Taken together, these results reveal a novel physiological role of the neuropeptide SIFa/SIFR pathway to regulate sleep through sleep-promoting neural circuits in the PI of adult fly brains.     

2种麻黄光合及其耐逆性分析

在河西临泽小泉子麻黄大田种植试验区和民勤沙生植物园中草药种植区,对多年生中麻黄(Ephedra intermedia Schrenk ex Mey.)和草麻黄(E.sinica Stapf)的光合速率、蒸腾速率及其影响因子进行测试分析,结果表明:(1)中麻黄和草麻黄的光合速率日变化均为单峰曲线,峰值均出现在11:00时,分别为12.098和11.560μmol.m-2.s-1。(2)中麻黄蒸腾速率日变化为单峰曲线,峰值在11:00时,为25.992 5 mol.m-2.s-1;草麻黄蒸腾速率日变化呈双峰曲线,峰值分别出现在11:00时与15:00时,峰值为26.280 0和24.3600 mol.m-2.s-1。(3)2种麻黄光合速率与光量子通量密度、大气温度、水汽压亏缺及蒸腾速率之间均呈显著或极显著正相关关系,与大气CO2浓度和胞间CO2浓度之间均呈显著或极显著负相关关系,与其余因子相关不显著。(4)2种麻黄水分利用效率对比分析显示,中麻黄水分利用效率值(平均0.9022)高于草麻黄(平均0.4532),表明中麻黄与草麻黄相比在生长过程中是以较低的蒸腾强度和相对较高的光合速率值来适应干旱荒漠环境的,比草麻黄更具抗干旱性。     

一株中型假丝酵母发酵木糖产乙醇的特性研究

本研究对自然界中筛选得到的1株可以发酵木糖产乙醇的中型假丝酵母(Candida intermedia)的特性进行了研究.该菌株在28℃、120 r/min、72 h条件下,发酵3%木糖的乙醇产率最高,达到理论值的43.70%,发酵7%木糖得到的乙醇产量最高,为6.480 g/L.发酵时间延长到156 h,可以利用8%木糖产乙醇21.225 g/L,产率为理论值的72.87%.该菌株还可以在同样条件下,发酵13%葡萄糖得到乙醇50.965 g/L,达到理论值的76.90%.以3% 2% 3%分批补加糖,比一次性发酵8%木糖的乙醇产量提高9.91%.在葡萄糖和木糖的混合培养基中,优先利用葡萄糖,同时还表现出葡萄糖对木糖发酵的促进作用,当2%的木糖与6%葡萄糖混合时,乙醇产量比两者单独发酵的加和提高了25%.     

Intercellular communication within the rat anterior pituitary: relationship between LH-RH neurons and folliculo-stellate cells in the pars tuberalis

The distribution of LH-RH-positive nerve fibers in the median eminence was demonstrated in the 1970s and 1980s. A few LH-RH fibers have been reported to be present in the adjacent pars tuberalis of the pituitary, but their functional significance has not been clarified and still remains enigmatic. Adult male Wistar-Imamichi rats were separated into two groups: one for immunohistochemistry of LH-RH and S-100 protein (for the identification of folliculo-stellate cells) and the other for electron microscopy. For both immunohistochemistry and electron microscopy, the specimens obtained contained the pituitary gland connected with the hypothalamus. Numerous LH-RH-positive fibers were observed as tiny lines with several varicosities both on the primary vascular plexus and in the hypothalamus corresponding to the posterior half of the portal vein area. LH-RH-positive fibers were also noted around S-100-positive cells in the pars tuberalis. Weakly reactive S-100 cells were scattered in the pars tuberalis in the midsagittal plane, while clusters of strong reactive elements occurred 100–300 m from the center. Similar observations were made using fluorescence immunohistochemistry for LH-RH and S-100, and at the electron-microscopic level. At the posterior portion of the portal vein system, bundles of the LH-RH-immunoreactive fibers invaded the pars tuberalis and terminated on agranular cells. Gap junctions were clearly seen among agranular cells corresponding to folliculo-stellate cells. It is postulated that the LH-RH message might be transmitted not only by the established hypophyseal portal vein system but also via the folliculo-stellate cells in the pars tuberalis to aid in the modulation of LH release.     

The hypophyseal pars tuberalis is enriched with distinct phosphotyrosine-containing proteins not detected in other areas of the brain and pituitary

The regulation of cell activity, growth and metabolism by a number of growth factor receptors and proto-oncogene products involves tyrosine kinase activity resulting in autophosphorylation of the receptors and production of phosphorylated tyrosine-containing protein substrates. The identification and precise localization of phosphotyrosine (PY)-containing proteins are first steps in elucidating the functional role of tyrosine kinases in the modulation of the central nervous system and related areas. In the present report, we describe PY-containing proteins in the median eminence and adjacent pars tuberalis of the rat adenohypophysis by immunocytochemistry using light and electron microscopy, and by Western blotting analysis. PY-immunoreactivity was found to be most intense throughout the cytoplasm of a population of epithelial pars tuberalis cells. Polyacrylamide gel electrophoresis and Western blotting of tissue extracts from various brain and pituitary regions demonstrated a general pattern of 4 major bands of PY-proteins, with an additional dense band representing a 44 kDa protein that was highly phosphorylated on tyrosines and that was exclusively found in the pars tuberalis. Additional investigation for the presence of insulin receptors, a tyrosine kinase previously correlated with the distribution of PY-proteins, demonstrated a receptor localization in axons and nerve terminals in the external and internal zone of the median eminence. However, the large amount of different PY-proteins present in the secretory cell population of the pars tuberalis could not be attributed to the insulin receptor. Our findings demonstrate that there is a large amount of cell-specific tyrosine kinase activity in the median eminence and contacting the pars tuberalis; these may play a significant role for transduction of biological signals or metabolic regulation in the neuroendocrine region.This paper is dedicated to Professor Dr. Leonhardt on the occasion of his 75th birthday     

Habitat Use and Survival of Preflight Wild Turkey Broods

Abstract: Wild turkey (Meleagris gallopavo) broods spend the first several days of life on the ground until poult flight capabilities are attained. This is a critical period of wild turkey life history, with poult survival ranging from 12% to 52%. We measured vegetation in plots used by Rio Grande wild turkey (M. g. intermedia) preflight broods at 4 sites in southwest Kansas and the Texas Panhandle, USA, to determine microhabitat selection for ground roosting and to determine if microhabitat was related to poult survival. Hens selected ground-roost locations with more visual obstruction from multiple observation heights than random sites. Plots surrounding ground roosts had 1) greater visual obstruction; 2) increased tree decay; 3) higher percent grass, shrub, litter, and forb cover; and 4) lower percent bare ground cover than random sites. Grass, shrubs, and downed trees appeared to provide desired cover for ground-roosting broods. Poult survival increased with age of poult, size of brood, and density of shrubs 1–2 m tall. Plots used by broods <10 days old with above average survival contained more visual obstruction and shrubs than plots used by broods 10–16 days old with above average survival, signifying a shift in habitat use by successful broods as poults attain flight abilities. Density of shrubs 1–2 m tall in brood-use areas appears to be important for poult survival to 16 days of age on southern Great Plains rangeland habitats. Ground-level vegetative cover appears to be a significant factor in preflight poult survival. Provisions of ground-level vegetative cover should be considered during wild turkey brooding periods where increased poult survival is desired.     

Incidence of Prevotella intermedia and Prevotella nigrescens in Periodontal Health and Disease

The incidence of black-pigmented rods (BPRs), especially Prevotella intermedia and Prevotella nigrescens, in periodontal health and disease were examined. Furthermore, the degradative enzyme activities of P. intermedia were compared among the strains from periodontal health and disease. Microbiological specimens were collected from subgingival crevice or periodontal pocket by paper point. The BPRs were found in 71.1% of periodontally healthy subjects (n = 45), and in 47.1% of healthy sites (n = 34) and 87.8% of active sites (n = 41) among periodontally diseased patients. Porphyromonas gingivalis was detected only in active sites of periodontally diseased patients (17.8% of 180 strains). P. intermedia was the predominant BPR in both healthy and active sites (37.3 and 41.7%, respectively) of the patients. However, P. nigrescens was the predominant BPR (70.5% of 173 strains) in periodontally healthy subjects. The enzyme activities of esterase, esterase-lipase, acid-phosphatase and α-fucosidase of P. intermedia strains isolated from active sites in patients were significantly higher (P < 0.05) than those of healthy subjects. The results suggest that P. intermedia might increase the activity of degradative enzymes under a certain condition and support the progression of periodontitis.     

SEPARATING SOUTHERN BLUE WHALE SUBSPECIES BASED ON LENGTH FREQUENCIES OF SEXUALLY MATURE FEMALES

When sexually mature, Antarctic (true) blue whales are substantially longer than pygmy blue whales. To estimate the proportions of these two subspecies in various regions, Bayesian mixture models were fitted to catch length frequencies of sexually mature females. The extent of rounding to 5-ft intervals was also estimated. Antarctic blue whales dominated (99.2%) pelagic catches south of 52°S, whereas pygmy blue whales dominated (99.9%) north of 52°S and in 35°–180°E. South of 60°S, only 0.7% (95% credibility interval 0.5%–1.0%) were pygmy blue whales, lower than the 7% upper bound currently assumed. Shore-based catches from SW Africa and those before 1937 from South Georgia and the South Shetlands were estimated to contain 90%–92% Antarctic blue whales. Actual proportions were probably higher, but these data show evidence of rounding (up to 19% of records), poor length-estimation methods, and other problems. The mean length of sexually mature female Chilean blue whales (77.1 ft, 23.5 m) was intermediate between pygmy (68.9 ft, 21.0 m) and Antarctic blue whales (83.4–86.3 ft, 25.4–26.6 m). A good fit to these data was obtained only by assuming that the Chilean whales are a separate subspecies or distinctive population. This finding is also consistent with their discrete distribution, and genetic and call type differences, compared to Antarctic and pygmy blue whales.     

Pi30 DNA probe may be useful for the identification of Prevotella intermedia at the species or strain level

Recently, we introduced a new method for the rapid screening of bacterial species-or subspecies-specific DNA probes, named the "inverted dot blot hybridization screening method." This method has subsequently been then applied to develop species-or strain-specific DNA probes for Prevotella intermedia and Prevotella nigrescens. In a previous study, the inverted dot blot hybridization data showed that a probe, Pi30, was specific for P. intermedia. In this study, the DNA probe Pi30 was evaluated by Southern blot analysis to determine if it could distinguish P. intermedia from P. nigrescens. The data showed that the probe Pi30 reacted with the genomic DNAs from the reference strains and clinical isolates of both P. intermedia and P. nigrescens, but the size of the signal bands was different. In addition, the probe Pi30 reacted with a 1.4 kbp fragment from the genomic DNAs digested with Pst I of the P. intermedia strains but not with any fragments of P. nigrescens strains. The result indicates that the probe Pi30 could be useful for the identification of P. intermedia by restriction fragment length polymorphism (RFLP) at the species or strain level.