Morphologic and hematologic characteristics of storage pool deficiency in beige rats (Chédiak-Higashi syndrome of rats)

Characterization of beige rats as having a platelet storage pool deficiency (SPD) was undertaken. Platelets from beige rats, an animal model of Chédiak-Higashi syndrome (CHS), completely lacked the ability to aggregate when stimulated with high dosages of collagen (50 micrograms/ml), and lacked secondary aggregation induced by adenosine diphosphate (ADP). Concentrations of ADP, ATP, and serotonin in the platelets of beige rats were significantly lower than those of control rats. However, platelet count remained within normal values. Electron microscopy revealed that platelets had fewer dense granules, whereas other organelles had normal structure. This morphologic and functional evidence confirms that platelets of beige rats have the typical characteristics of SPD.     

Abnormal mast cell granules in the beige (Chédiak-Higashi syndrome) mouse.

Mast cells of beige (C57BL/6J) (bg-j/bg-j) mice were examined histochemically and ultrastructurally. Mast cell granules in the beige mice were markedly enlarged and irregular in shape. Granule contents stained uniformly with acidified toluidine blue, but with ruthenium red and Alcian Blue-safranin, two components were evident. The rims of the abnormal granules stained with ruthenium red and with Alcian Blue; the centers of the granules were clear with ruthenium red and stained with safranin. Mast cell granules thus represent another abnormal organelle in the Chédiak-Higashi syndrome.     

Presence of Ctenocephalides canis (Curtis) and Ctenocephalides felis (Bouché) infesting dogs in the city of Aguascalientes, México

Prevalence and seasonal distribution of Ctenocephalides canis (Curtis) and Ctenocephalides felis (Bouché) infestations in urban dogs of the city of Aguascalientes, Mexico, were studied. Between January and December 2007, 863 dogs in the Municipal Canine and Feline Control Center were examined. Overall prevalence of infestation was 12% (95% CI 10-14). Seasonal distribution revealed that prevalences in spring and summer were highest, while autumn and winter had lower prevalences. Two infestation peaks were observed, i.e., in April (17.7%) and July (18.9%). A positive correlation was detected between prevalence and temperature during the winter season (P < 0.05). Prevalence in relation to gender showed that males were more frequently infested, 14% (95% CI 11-17), than females, 9.4% (95% CI 7-13); hair length did not affect differences in prevalence. Six hundred twenty-nine fleas were examined; 62% were C. canis and 38% C. felis . Dogs infested with only C. canis were 48% (95% CI 38-58), while 18% were infested only with C. felis (95% CI 11-27); the remainder, 34% (95% CI 24-44), had mixed infestations.     

‘3 + 1’ mixed-ligand oxorhenium(V) complexes and their inhibition of the cysteine proteases cathepsin B and cathepsin K

The synthesis of several new oxorhenium(V) complexes containing the ‘3 + 1’ mixed-ligand donor set, ReO(SXS)(SR) (where X = S, O, N(R′); R = alkyl, aryl, heterocylce; R′ = H, alkyl, aryl), is described. The X-ray structure for four of these complexes ReO(SN(Ph)S)(SPh) (6), ReO(SN(CH₂CH₂NMe₂)S)(SPhOMe-p) (10), ReO(SOS)(SPh) (29) and ReO(SOS)(SPhNO₂-p) (30) was determined. The inhibitory activity of all of the oxorhenium(V) complexes reported herein was evaluated against the cysteine proteases cathepsin B and K in vitro. Compound 25, ReO(SSS)(S-4py) · HCl, was the best inhibitor of the series against cathepsin B with an IC₅₀ of 10 nM. Several of the complexes exhibited specificity for cathepsin B over K, suggesting that oxorhenium(V) complexes can be designed to be enzyme specific. The results described in this paper show that the oxorhenium(V) ‘3 + 1’ complexes are potent inhibitors of cathepsin B and K, constituting promising potential for the treatment of cancer and osteoporosis, respectively.     

Seston dynamics and bivalve feeding in the Bay of Marennes-Oléron (France)

Within the framework of an investigation into the carrying capacity of the Bay of Marennes-Oléron (France) for bivalve culture, thein situ uptake of suspended particulate material by oysters (Crassostrea gigas) and mussels (Mytilus edulis) was determined in experiments with benthic ecosystem tunnels. Very high fluctuations in seston quantity and quality were observed within and between tidal cycles. The percentage of organic carbon was inversely related to seston quantity at low concentrations. Organic carbon was diluted by resuspension of material rich in inorganic matter. At high seston concentrations a constant level of about 2% organic carbon was found. The C/N ratio was relatively constant throughout the seasons and fairly low (6.5 to 8.4). Owing to the presence of bivalves large fluxes of suspended particulate material were observed in thein situ measurements. Selective retention of organic carbon or nitrogen could not be demonstrated. Clearance rates based on chlorophyll uptake were within a normal range compared to other studies. A large contribution to the food of the bivalves seemed to be formed by resuspended microphytobenthos. Judged by the low C/N ratio, the food was of good quality. Although its quantity was variable by dilution, it may support largely the carrying capacity of the Bay of Marennes-Oléron for the cultivation of bivalves. Communication no. 687 of the Netherlands Institute of Ecology, Centre for Estuarine and Coastal Ecology, Yerseke, the Netherlands.     

Long-Distance Wind-Borne Dispersal of Sitodiplosis mosellana Géhin (Diptera:Cecidomyiidae) in Northern China

Surveys based on the density of the adult wheat midge, Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae), were conducted at ground level and at heights between 10 and 75 m in Xushui county (39.02 °N, 115.65 °E), Hebei province, China, in 2011. The HYSPLIT-4 model was used to analyze the possible dispersion trajectories and distances of S. mosellana depending on the experimental location. The wheat midges were trapped at altitudes from 10 to 75 m a.g.l. strongly suggest that they might also be present at much higher altitudes, where potentially, they could take advantage of the fast moving air currents. 6-h backward-trajectories indicate that adult S. mosellana could have come from both north and south, and the trajectory distances were 25–107 Km. 6-h forward-trajectories indicate that adults most likely migrated to an area located in Tianjin, Beijing and northern Hebei province, north china, and the trajectory distances were 28–195 Km. In this study, no male midges were captured at 10 m or above, which suggest male midges don’t engage in wind borne long distance migration, suggesting S. mosellana mated before dispersal. The information presented here is helpful to alter the way we view their migration over limited distances and add to our ability in outbreak forecasts.     

Raspberry promotes brown and beige adipocyte development in mice fed high-fat diet through activation of AMP-activated protein kinase (AMPK) α1

Development of brown and beige/brite adipocytes increases thermogenesis and helps to reduce obesity and metabolic syndrome. Our previous study suggests that dietary raspberry can ameliorate metabolic syndromes in diet-induced obese mice. Here, we further evaluated the effects of raspberry on energy expenditure and adaptive thermogenesis and determined whether these effects were mediated by AMP-activated protein kinase (AMPK). Mice deficient in the catalytic subunit of AMPKα1 and wild-type (WT) mice were fed a high-fat diet (HFD) or HFD supplemented with 5% raspberry (RAS) for 10 weeks. The thermogenic program and related regulatory factors in adipose tissue were assessed. RAS improved the insulin sensitivity and reduced fat mass in WT mice but not in AMPKα1^-/- mice. In the absence of AMPKα1, RAS failed to increase oxygen consumption and heat production. Consistent with this, the thermogenic gene expression in brown adipose tissue and brown-like adipocyte formation in subcutaneous adipose tissue were not induced by RAS in AMPKα1^-/- mice. In conclusion, AMPKα1 is indispensable for the effects of RAS on brown and beige/brite adipocyte development, and prevention of obesity and metabolic dysfunction.     

Numerical increases and distributional shifts of Chrysaora quinquecirrha (Desor) and Aurelia aurita (Linné) (Cnidaria: Scyphozoa) in the northern Gulf of Mexico

Fisheries resource trawl survey data from the National Marine Fisheries Service from a 11–13-year period to 1997 were examined to quantify numerical and distributional changes of two species of northern Gulf of Mexico scyphomedusae: the Atlantic sea nettle, Chrysaora quinquecirrha (Desor), and the moon jelly, Aurelia aurita (Linné). Trawl surveys were grouped into 10 statistical regions from Mobile Bay, Alabama to the southern extent of Texas, and extended seaward to the shelf break. Records of summertime C. quinquecirrha medusa populations show both an overall numerical increase and a distributional expansion away from shore in the down-stream productivity field of two major river system outflows: Mobile Bay and the Mississippi-Atchafalaya Rivers. In addition, there is a significant overlap between summer C. quinquecirrha and lower water column hypoxia on the Louisiana shelf. In trawl surveys from the fall, A. aurita medusae showed significant trends of numerical increase in over half of the regions analyzed. For both species, there were statistical regions of no significant change, but there were no regions that showed significant decrease in number or distribution. The relationships between natural and human-induced (e.g. coastal eutrophication, fishing activity and hard substrate supplementation) ecosystem modifications are very complex in the Gulf of Mexico, and the potential impact of increased jellyfish populations in one of North America's most valuable fishing grounds is a most critical issue. Several hypotheses are developed and discussed to guide future research efforts in the Gulf of Mexico.     

The locations of cathepsin activity and β-glucuronidase in the Guerin T8 tumour

Tumour homogenate fractions, isolated by differential centrifugation, were subfractionated by density-gradient centrifugation. Biochemical and electron microscopic analyses revealed that beta-glucuronidase and cathepsin activity were associated with a class (possibly two) of lysosomal particles of density greater than those of mitochondria and the endoplasmic reticulum. Lysosomes sedimented by low g forces were vacuolar, electron-dense, delineated by a unit membrane and about 0.2mum in diameter. beta-Glucuronidase was also apparently associated with ribosomes whereas cathepsin was bound in part to the endoplasmic reticulum. Catalase and glucose 6-phosphatase possessed slightly different density-gradient sedimentation profiles.     

Associations of aquatic insects (Ephemeroptera,Plecoptera, and Trichoptera) in a network of subarctic lakes and streams in Québec

As part of an impact assessment of large hydroelectric projects in the James Bay drainage in Northwestern Québec, the aquatic insect communities were studied in a network of rivers, lakes and streams during the summer of 1975. Thirty-eight emergence traps operated over the ice-free season yielded 10 888 insects (5559 Ephemeroptera, 2817 Plecoptera, and 2512 Trichoptera), representing 148 species (respectively 44, 18, and 86), most of temperate and boreal afinities. There was no arctic element.Similarity analyses and clustering procedures on the emergence series revealed the existence of distinct insect communities in the river (fast and slow sections), the streams (fast and slow), the lakes and the bogs, each characterized by a particular assemblage of species. Many of the species were more or less ubiquitous and differences between communities were marked more by changes in the dominance of the species and differences in the frequency distributions, than absolute shifts in the species lists. The yields in the traps set in fast water were much greater than those in slow running water, and these in turn greater than those of standing water.By comparison with more southerly sites, the seasonal succession of species was retarded in the spring and early summer, but was not shortened appreciably in the fall. The usual emergence patterns associated with these taxa was observed, namely those of spring, summer and autumn species.     

Simultaneous enzyme overlay membrane (EOM)-based in situ zymography and immunofluorescence technique reveals cathepsin B-like activity in a subset of tumour vessels

The analysis of the invasion front of oral squamous cell carcinoma (OSCC) has revealed a fundamental invasion-associated remodelling of the extracellular matrix as the result of a complex regulated interplay of matrix synthesis and matrix degradation. Cysteine proteinases, in particular cathepsin B, are implicated in tumour invasion in vivo and in vitro and are thought to be important mediators of metastasis. An in situ zymographic assay based on enzyme overlay membranes (EOMs) was established to define the tissue localisation of cathepsin B activity in OSCC. Using confocal laser scanning microscopy we present a double-labelling method for the rapid and reproducible simultaneous detection of cathepsin B-like activity and cellular or extracellular antigens based on an EOM and immunofluorescence technique on frozen sections. Applying this method, cathepsin B-like activity was mainly found in vascular structures within the invasive front of OSCC. Therefore, the results suggest a particular pathogenic role of cathepsin B in tumour angioneogenesis. The method can simply be transferred to other enzymes and can be recommended for more extensive studies of proteolytic activity in human malignancies.     

Prevalence and familial patterns of night eating in the Québec adipose and lifestyle investigation in youth (QUALITY) study

The prevalence and familial patterns of night eating syndrome (NES) in families enrolled in the Québec Adipose and Lifestyle InvesTigation in Youth (QUALITY) study was examined. Families (n = 395; one child, mother, and father for whom at least one parent was obese or had abdominal obesity) completed the Night Eating Questionnaire (NEQ) as part of a longitudinal study on the development of metabolic disease in children at risk for obesity. Responses on the NEQ were used to establish a diagnosis of NES and to determine the correlation and heritability of NES symptoms in families. Using comprehensive research diagnostic criteria, full threshold NES was rare: 0% of children, 0.5% of mothers, and 0.3% of fathers met criteria. When controlling for age, sex, and BMI, NEQ scores of spouses were not significantly correlated, but mothers' NEQ scores were significantly correlated with the scores of both sons (r = 0.19, P < 0.001) and daughters (r = 0.15, P = 0.05). The heritability of NEQ scores was 0.24 when controlling for age, sex, and BMI. These findings replicate previous research suggesting a low prevalence of night eating behavior in children and the aggregation of NES in families.     

Annatto extract and β-carotene enhances antioxidant status and regulate gene expression in neutrophils of diabetic rats

Annatto (Bixa orellana L.) contains a mixture of orange-yellowish pigments due to the presence of various carotenoids that have antioxidant effect. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen and nitrogen species (ROS and RNS) as part of the body's defence mechanisms to destroy invading pathogens. It is well known that the function of neutrophils is altered in diabetes; one of the major functional changes in neutrophils in diabetes is the increased generation of extracellular superoxide via the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system. The purpose of this study is to evaluate the production of ROS and nitric oxide (NO) as well as the expression of NADPH oxidase subunits, inducible nitric oxide (iNOS), superoxide dismutase (SOD) and catalase (CAT) in neutrophils from diabetic rats treated with annatto extract and β-carotene. Forty-eight female Fisher rats were distributed into six groups according to the treatment received. All animals were sacrificed 7 days after treatment, and the neutrophils were isolated using two gradients of different densities. The ROS and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Analyses of gene expression were performed using quantitative real time polymerase chain reaction (qRT-PCR). The results show that treatment with annatto extract and β-carotene was able to decrease ROS production and the mRNA levels of p22(phox) and p47(phox) and increase the mRNA levels of SOD and CAT in neutrophils from diabetic rats. These data suggest that annatto extract and β-carotene exerts antioxidant effect via inhibition of expression of the NADPH oxidase subunits and increase expression/activity of antioxidant enzymes.     

Immunohistochemical detection of cathepsin D, K, and L in the process of endochondral ossification in the human

Cathepsins D, K, and L were immunolocalized in tissue undergoing endochondral ossification in the human. Cathepsins D, K, and L were localized in osteoclasts and chondroclasts attached to bone matrix and cartilage matrix, respectively. Cathepsins D and L were immunostained in chondrocytes. Immunolocalization of cathepsin D was limited to hypertrophic chondrocytes adjacent to the osteochondral junction. In contrast, cathepsin L was immunolocalized in both proliferating and hypertrophic chondrocytes. In the bone marrow space, cathepsins D, K, and L were localized in multinucleated cells. Cathepsin D was diffusely detected in mononuclear bone marrow cells which were negative for cathepsins K and L. The present findings indicated that cathepsins K, D, and L were associated with the process of endochondral ossification in the human, and suggested that these cathepsins share roles in bone and cartilage turnover in the human.     

The role of food in the population dynamics of Orchesella cincta (Linné) (Collembola)

Summary The feeding activity of the collembolan species Orchesella cincta (Linné) was studied in the laboratory and in the field. In the laboratory it was shown that at any one time only about 50–60% of the animals were feeding; the remainder were occupied with molting activities. Most of the time similar values were obtained in the field but during winter and during dry summer periods high percentages of empty guts could be demonstrated, indicating an absence or inaccessability of food. When favorable weather returned, a high feeding activity was again observed. Laboratory experiments and field observations indicate that temporary starvation periods are followed by synchronization of the molting and reproductive rhythms and an apparent increase in longevity. These phenomena are important for the restoration of the population after unfavorable periods but reduce the stabilizing force of food scarcity.