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31.
The dog is the main reservoir of Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in humans in Southern Europe. In order to identify the risk of dogs from
a Leishmania non-endemic area traveling to a Leishmania -endemic area becoming infected and the risk of transmitting infection to humans in non-endemic areas an investigation was
performed, in which the results of a questionnaire were combined with the results of a serologic survey. 相似文献
32.
Massimiliano de Zambotti Aimee Goldstone Stephanie Claudatos Ian M. Colrain Fiona C. Baker 《Chronobiology international》2018,35(4):465-476
We evaluated the performance of a consumer multi-sensory wristband (Fitbit Charge 2?), against polysomnography (PSG) in measuring sleep/wake state and sleep stage composition in healthy adults.In-lab PSG and Fitbit Charge 2? data were obtained from a single overnight recording at the SRI Human Sleep Research Laboratory in 44 adults (19—61 years; 26 women; 25 Caucasian). Participants were screened to be free from mental and medical conditions. Presence of sleep disorders was evaluated with clinical PSG. PSG findings indicated periodic limb movement of sleep (PLMS, > 15/h) in nine participants, who were analyzed separately from the main group (n = 35). PSG and Fitbit Charge 2? sleep data were compared using paired t-tests, Bland–Altman plots, and epoch-by-epoch (EBE) analysis.In the main group, Fitbit Charge 2? showed 0.96 sensitivity (accuracy to detect sleep), 0.61 specificity (accuracy to detect wake), 0.81 accuracy in detecting N1+N2 sleep (“light sleep”), 0.49 accuracy in detecting N3 sleep (“deep sleep”), and 0.74 accuracy in detecting rapid-eye-movement (REM) sleep. Fitbit Charge 2? significantly (p < 0.05) overestimated PSG TST by 9 min, N1+N2 sleep by 34 min, and underestimated PSG SOL by 4 min and N3 sleep by 24 min. PSG and Fitbit Charge 2? outcomes did not differ for WASO and time spent in REM sleep. No more than two participants fell outside the Bland–Altman agreement limits for all sleep measures. Fitbit Charge 2? correctly identified 82% of PSG-defined non-REM–REM sleep cycles across the night. Similar outcomes were found for the PLMS group.Fitbit Charge 2? shows promise in detecting sleep-wake states and sleep stage composition relative to gold standard PSG, particularly in the estimation of REM sleep, but with limitations in N3 detection. Fitbit Charge 2? accuracy and reliability need to be further investigated in different settings (at-home, multiple nights) and in different populations in which sleep composition is known to vary (adolescents, elderly, patients with sleep disorders). 相似文献
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34.
Physicochemical modifications of lysosomal hydrolases during intracellular transport 总被引:13,自引:10,他引:3
1. The following fractions were prepared from rat kidney and characterized ultrastructurally, biochemically and enzymically: (a) an ordinary rough microsomal (RM(1)) fraction; (b) a special rough microsomal (RM(2)) fraction enriched seven- to nine-fold in acid hydrolases over the homogenate; (c) a smooth microsomal (SM) fraction; (d) a Golgi (GM) fraction enriched 2.5-fold in acid hydrolases and 10-, 15- and 20-fold in sialyltransferase, N-acetyl-lactosamine synthetase and galactosyltransferase respectively; (e) a lysosomal (L) fraction enriched 15- to 23-fold in acid hydrolases. The frequency of Golgi sacs and tubules seen in the electron microscope and the specific activity of the three glycosyltransferases in these fractions increased in the order: RM(2)相似文献
35.
Isolation and characterization of a rough microsomal fraction from rat kidney that is enriched in lysosomal enzymes 总被引:8,自引:7,他引:1
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Alfred Goldstone Harold Koenig Rajinder Nayyar Charles Hughes Chung Y. Lu 《The Biochemical journal》1973,132(2):259-266
1. A special population of rough microsomal material (microsomes) rich in lysosomal acid hydrolases was separated by isopycnic centrifugation as a discrete fraction (RM(2)) from the bulk of rough microsomal material in rat kidney because of its greater density. 2. The specific activities of five acid hydrolases in the RM(2) fraction were approximately one-half those of a purified lysosomal (L) fraction and 10- to 30-fold greater than those of an ordinary rough microsomal (RM(1)) fraction. 3. These special rough microsomes have a distinctive ultrastructure and electron-cytochemical properties. Their cisternal content resembles the matrix of lysosomes in that it is electron-dense, osmiophilic and plumbophilic and gives a positive reaction for acid phosphatase activity. 4. Polyacrylamide-gel electrophoresis of soluble proteins from the L fraction resolved nine anionic glycoproteins, most of which exhibit acid hydrolase activities (Goldstone & Koenig, 1970, 1973; Goldstone et al., 1971a). The most anionic glycoprotein is the acidic lipoglycoprotein of the lysosomal matrix (Goldstone et al., 1970). 5. Polyacrylamide-gel electrophoresis of soluble proteins from the RM(2) fraction resolved two cationic glycoproteins with acid hydrolase activities (Goldstone & Koenig, 1973) and an anionic glycoprotein with the same electrophoretic mobility as the lysosomal lipoglycoprotein, but without its lipid constituents or capacity to bind the basic fluorochrome Acridine Orange. These constituents are considered to be the precursors of the lysosomal glycoproteins. 相似文献
36.
Sister kinetochore recapture in fission yeast occurs by two distinct mechanisms, both requiring Dam1 and Klp2 总被引:3,自引:1,他引:2
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Gachet Y Reyes C Courthéoux T Goldstone S Gay G Serrurier C Tournier S 《Molecular biology of the cell》2008,19(4):1646-1662
In eukaryotic cells, proper formation of the spindle is necessary for successful cell division. We have studied chromosome recapture in the fission yeast Schizosaccharomyces pombe. We show by live cell analysis that lost kinetochores interact laterally with intranuclear microtubules (INMs) and that both microtubule depolymerization (end-on pulling) and minus-end-directed movement (microtubule sliding) contribute to chromosome retrieval to the spindle pole body (SPB). We find that the minus-end-directed motor Klp2 colocalizes with the kinetochore during its transport to the SPB and contributes to the effectiveness of retrieval by affecting both end-on pulling and lateral sliding. Furthermore, we provide in vivo evidence that Dam1, a component of the DASH complex, also colocalizes with the kinetochore during its transport and is essential for its retrieval by either of these mechanisms. Finally, we find that the position of the unattached kinetochore correlates with the size and orientation of the INMs, suggesting that chromosome recapture may not be a random process. 相似文献
37.
38.
White Nicholas J Ashley Elizabeth A Recht Judith Delves Michael J Ruecker Andrea Smithuis Frank M Eziefula Alice C Bousema Teun Drakeley Chris Chotivanich Kesinee Imwong Mallika Pukrittayakamee Sasithon Prachumsri Jetsumon Chu Cindy Andolina Chiara Bancone Germana Hien Tran T Mayxay Mayfong Taylor Walter RJ von Seidlein Lorenz Price Ric N Barnes Karen I Djimdé Abdoulaye ter Kuile Feiko Gosling Roly Chen Ingrid Dhorda Mehul J Stepniewska Kasia Guérin Philippe Woodrow Charles J Dondorp Arjen M Day Nicholas PJ Nosten Francois H 《Malaria journal》2014,13(1):1-14
Background
Effective mating between laboratory-reared males and wild females is paramount to the success of vector control strategies aiming to decrease disease transmission via the release of sterile or genetically modified male mosquitoes. However mosquito colonization and laboratory maintenance have the potential to negatively affect male genotypic and phenotypic quality through inbreeding and selection, which in turn can decrease male mating competitiveness in the field. To date, very little is known about the impact of those evolutionary forces on the reproductive biology of mosquito colonies and how they ultimately affect male reproductive fitness.Methods
Here several male reproductive physiological traits likely to be affected by inbreeding and selection following colonization and laboratory rearing were examined. Sperm length, and accessory gland and testes size were compared in male progeny from field-collected females and laboratory strains of Anopheles gambiae sensu stricto colonized from one to over 25 years ago. These traits were also compared in the parental and sequentially derived, genetically modified strains produced using a two-phase genetic transformation system. Finally, genetic crosses were performed between strains in order to distinguish the effects of inbreeding and selection on reproductive traits.Results
Sperm length was found to steadily decrease with the age of mosquito colonies but was recovered in refreshed strains and crosses between inbred strains therefore incriminating inbreeding costs. In contrast, testes size progressively increased with colony age, whilst accessory gland size quickly decreased in males from colonies of all ages. The lack of heterosis in response to crossing and strain refreshing in the latter two reproductive traits suggests selection for insectary conditions.Conclusions
These results show that inbreeding and selection differentially affect reproductive traits in laboratory strains overtime and that heterotic ‘supermales’ could be used to rescue some male reproductive characteristics. Further experiments are needed to establish the exact relationship between sperm length, accessory gland and testes size, and male reproductive success in the laboratory and field settings. 相似文献39.
40.