Olfactory Cue Mediated Neonatal Recognition in Sheep, Ovis aries

The strong bond between ewe and lamb formed shortly after parturition is an important factor in lamb survival. Evidence exists that a ewe can distinguish her lamb by its unique smell, but the constituents of such a putative olfactory cue have not yet been identified. We have now identified 133 volatile organic compounds associated with the wool of Döhne Merino lambs that we presume may be involved in neonatal recognition. Quantitative analysis and comparison of odor profiles of the twins of 16 ewes (9.69% sample group) of a flock of 165 twin-bearing ewes revealed that the wool volatiles of twins are qualitatively and quantitatively similar, but differ from those of other twins or non-twin lambs in the flock. The 88 constituents present in at least 20% of the analyzed wool samples were considered as variables for multivariate analysis. A P-value?相似文献   

A murine and a porcine coronavirus are released from opposite surfaces of the same epithelial cells

Epithelial cells are important target cells for coronavirus infection. Earlier we have shown that transmissible gastroenteritis coronavirus (TGEV) and mouse hepatitis coronavirus (MHV) are released from different sides of porcine and murine epithelial cells, respectively. To study the release of these viruses from the same cells, we constructed a porcine LLC-PK1 cell line stably expressing the recombinant MHV receptor cDNA (LMR cells). The MHV and TGEV receptor glycoproteins were shown by immunofluorescence to appear at the surface of the cells and to be functional so that the cells were susceptible to both MHV and TGEV infection. Both coronaviruses entered polarized LMR cells only through the apical surface. Remarkably, while the cells remained susceptible to TGEV for long periods, infectability by MHV decreased with time after plating of the cells onto filters. This was not due to a lack of expression of the MHV receptor, since this glycoprotein was still abundant on the apical surface of these cells. TGEV and MHV appeared to exit LMR cells from opposite sides. Whereas TGEV was released preferentially at the apical membrane, MHV was released preferentially at the basolateral surface. These results show that vesicles containing the two coronaviruses are targeted differently in LMR cells. We propose that the viruses are sorted at the Golgi complex into different transport vesicles that carry information directing them to one of the two surface domains. The apical release of TGEV and the basolateral release of MHV might be factors contributing to the difference in virus spread found between TGEV and MHV in their respective natural hosts, the former causing mainly a localized enteric infection, the latter spreading through the body to other organs.     

rhuIL-2 adjunctive therapy in multidrug resistant tuberculosis: a comparison of two treatment regimens and placebo

SETTING: Low-dose recombinant human interleukin 2 (rhuIL-2) adjunctive immunotherapy in multidrug resistant tuberculosis (MDR-TB) patients. OBJECTIVE: Evaluation of the effects of daily versus pulse-administered rhuIL-2 compared to placebo. DESIGN: MDR-TB patients on best available antituberculous chemotherapy received rhuIL-2 for 30 consecutive days (daily therapy), or for 5 days followed by a 9-day 'rest', for three cycles (pulse therapy). Placebo control patients received diluent. The cumulative total dose of rhuIL-2 given to each patient in either rhuIL-2 treatment group was the same. Patient immunologic, microbiologic, and radiologic responses were compared. RESULTS: The three treatment schedules induced different results. Immune activation was documented in patients receiving daily rhuIL-2 therapy. Numbers of CD25+ and CD56+ cells in the peripheral blood were increased in these patients, but not in patients receiving pulse rhuIL-2 or placebo. In addition, 5/8 (62%) patients receiving daily rhuIL-2 demonstrated reduced or cleared sputum bacterial load while only 2/7 (28%) pulse rhuIL-2 treated and 2/8 (25%) controls showed bacillary clearance. Chest radiographs of 7/12 (58%) patients receiving daily rhuIL-2 indicated significant improvement over 6 weeks. Only 2/9 (22%) pulse rhuIL-2-treated patients and 5/12(42%) placebo controls showed radiologic improvement. CONCLUSION: Daily low dose rhuIL-2 adjunctive treatment stimulates immune activation and may enhance the antimicrobial response in MDR-TB.     

Fabrication of a finegrain composite material based on the Al2O3-SiO2-ZrO2 system

The effect of the composition and the method of treatment of mullite-zircon powder on the kinetics of the densification, the strength, and the microstructure of the sintered material is described. It is shown that a fine-grain material with minimum porosity can be obtained based on kaolin by combining the sol-gel method and conventional powder technology with preliminary dry activation of the powder. Translated from Ogneupory i Tekhnicheskaya Keramika, No. 2, pp. 6–8, February, 2000.     

Angiotensin II Regulates microRNA-132/-212 in Hypertensive Rats and Humans

MicroRNAs (miRNAs), a group of small non-coding RNAs that fine tune translation of multiple target mRNAs, are emerging as key regulators in cardiovascular development and disease. MiRNAs are involved in cardiac hypertrophy, heart failure and remodeling following cardiac infarction; however, miRNAs involved in hypertension have not been thoroughly investigated. We have recently reported that specific miRNAs play an integral role in Angiotensin II receptor (AT₁R) signaling, especially after activation of the Gαq signaling pathway. Since AT₁R blockers are widely used to treat hypertension, we undertook a detailed analysis of potential miRNAs involved in Angiotensin II (AngII) mediated hypertension in rats and hypertensive patients, using miRNA microarray and qPCR analysis. The miR-132 and miR-212 are highly increased in the heart, aortic wall and kidney of rats with hypertension (159 ± 12 mm Hg) and cardiac hypertrophy following chronic AngII infusion. In addition, activation of the endothelin receptor, another Gαq coupled receptor, also increased miR-132 and miR-212. We sought to extend these observations using human samples by reasoning that AT₁R blockers may decrease miR-132 and miR-212. We analyzed tissue samples of mammary artery obtained from surplus arterial tissue after coronary bypass operations. Indeed, we found a decrease in expression levels of miR-132 and miR-212 in human arteries from bypass-operated patients treated with AT₁R blockers, whereas treatment with β-blockers had no effect. Taken together, these data suggest that miR-132 and miR-212 are involved in AngII induced hypertension, providing a new perspective in hypertensive disease mechanisms.     

A Comparative Characterization of Kaolins of Provenance from the Prosyanovskoe and Kyshtymskoe Deposits Subjected to Mechanochemical Activation in an Aqueous Medium

The effect of mechanical activation in an aqueous medium on properties of kaolins of provenance from the Prosyanovskoe and Kyshtymskoe deposits — typical representatives of high-grade and low-grade kaolins — is studied. The activation in an aqueous medium produces a substantial effect on the crystallinity of kaolins and the process of phase formation in heat-treated kaolins. The mechanochemical activation, backed up by an accumulated and systematized experimental data, can provide a simple and readily available way toward improving the quality of kaolins.     

A comparison of mouse and speech input control of a text-annotation system

An experiment was designed to determine whether speech input is a valuable alternative or addition to manual input. Subjects used both speech and mouse input for control purposes in a document-annotation system. Speech recognition was realized by a speaker-dependent speech-recognition board. In separate sessions, subjects used either a mouse or speech interface, and comparisons were made between the two media in performance speed, number of commands, and number of errors. In a third session, subjects were free to use either input medium, and measures included both objective (usage) and subjective (questionnaire) preferences for the two media. The main results were that: (1)9 out of 24 subjects used speech more than the mouse when they were free to use both; (2) 21% of the subjects preferred speech control, because it allowed other devices to be operated manually; and (3) 37% of the subjects preferred to control the system with both input devices available. Speech can be a valuable addition to other input media enabling users to adapt their choice of media to specific task situations.     

The influence of the level of free-choice learning activities on the use of an educational computer game

Employing a mixed-method explorative approach, this study examined the in situ use of and opinions about an educational computer game for learning English introduced in three schools offering different levels of freedom to choose school activities. The results indicated that the general behaviour of the children with the game was very different for each of the schools while there were no significant differences in subjective opinions or previous computer game experience as measured with a questionnaire. The gaming records and interviews informed that children do enjoy playing the game in comparison with other formal learning activities, but appreciate it less as a leisure-time activity. Furthermore it appears that children used to teacher-initiated activities tend to depend on their teacher’s directions for how and when to play. The study highlights the level of choice as one of the important aspects to consider when introducing a game in the classroom. The study also points out some suggestions for the design of educational games, such as providing communication possibilities between players and integrating fast-paced motor-skill based games with learning content in a meaningful way.