Studies on vitamin E and selenium deficiency in young pigs. III. Effect on kinetics of erythrocyte production and destruction.

The effect of vitamin E and/or selenium deficiency on the kinetics of erythrocyte production and destruction has been investigated in swine. The plasma iron turnover rate, 59Fe incorporation into newly formed red cells as well as the 51Cr apparent red cell half-life, were not found to be significantly affected by either vitamin E deficiency, selenium deficiency or deficiency of both, as compared to replete animals. The results of this study suggest that vitamin E is not a limiting factor for normal erythropoiesis in young growing pigs. Erythropoiesis appeared, however, to be slightly decreased in selenium deficient pigs and will need to be further investigated.     

Evaluation of an Omental Pedicle Extension Technique in the Dog

A two-step omental pedicle extension technique was performed on 10 dogs. Step 1 of the pedicle extension involved release of the dorsal leaf of the omentum from its pancreatic attachment, whereas step 2 consisted of an inverse L-shaped incision to double the length of the pedicle. The pedicle dimensions were measured and the distance reached when extended toward the hind limb, forelimb, and the muzzle recorded after each stage of the procedure. The vascular patency of the pedicle was determined by intravenous injection of flu-orescein dye after the second stage of omental extension. Mean pedicle lengths were 44.5 cm with the first stage of extension and 82.0 cm after full extension. The mean width at the caudal extent of the pedicles after dorsal and full extension was 30.4 cm and 17.2 cm, respectively. Eight of the 10 pedicles were patent after full extension. The fully extended omental pedicles reached and, in most cases, extended beyond the distal extremities and the muzzle. The findings in this study suggest that the canine omentum can be extended to any part of the body without being detached from its vascular supply.     

紫甘薯红色素提取技术的研究

以紫甘薯为原料,研究了溶剂浸提法、超声波萃取法和微波萃取法对紫甘薯红色素的提取效果。结果表明:溶剂浸提法虽提取率较高,但提取时间较长;超声波萃取法的提取率较低;微波萃取法是一种较好的提取方法,在1.0%的柠檬酸水溶液,料液比1:40,微波辐射功率700W,辐射时间45s的条件下,提取3次,提取量可达到9.469mg.g-1。     

Prevention of organ allograft rejection by a specific Janus kinase 3 inhibitor

Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings.     

Holocene deglaciation of Marie Byrd Land,West Antarctica

Surface exposure ages of glacial deposits in the Ford Ranges of western Marie Byrd Land indicate continuous thinning of the West Antarctic Ice Sheet by more than 700 meters near the coast throughout the past 10,000 years. Deglaciation lagged the disappearance of ice sheets in the Northern Hemisphere by thousands of years and may still be under way. These results provide further evidence that parts of the West Antarctic Ice Sheet are on a long-term trajectory of decline. West Antarctic melting contributed water to the oceans in the late Holocene and may continue to do so in the future.     

Magnetic resonance spectroscopy identifies neural progenitor cells in the live human brain

The identification of neural stem and progenitor cells (NPCs) by in vivo brain imaging could have important implications for diagnostic, prognostic, and therapeutic purposes. We describe a metabolic biomarker for the detection and quantification of NPCs in the human brain in vivo. We used proton nuclear magnetic resonance spectroscopy to identify and characterize a biomarker in which NPCs are enriched and demonstrated its use as a reference for monitoring neurogenesis. To detect low concentrations of NPCs in vivo, we developed a signal processing method that enabled the use of magnetic resonance spectroscopy for the analysis of the NPC biomarker in both the rodent brain and the hippocampus of live humans. Our findings thus open the possibility of investigating the role of NPCs and neurogenesis in a wide variety of human brain disorders.     

Observed flow compensation associated with the MOC at 26.5 degrees N in the Atlantic

The Atlantic meridional overturning circulation (MOC), which provides one-quarter of the global meridional heat transport, is composed of a number of separate flow components. How changes in the strength of each of those components may affect that of the others has been unclear because of a lack of adequate data. We continuously observed the MOC at 26.5 degrees N for 1 year using end-point measurements of density, bottom pressure, and ocean currents; cable measurements across the Straits of Florida; and wind stress. The different transport components largely compensate for each other, thus confirming the validity of our monitoring approach. The MOC varied over the period of observation by +/-5.7 x 10(6) cubic meters per second, with density-inferred and wind-driven transports contributing equally to it. We find evidence for depth-independent compensation for the wind-driven surface flow.     

Host resistance to lung infection mediated by major vault protein in epithelial cells

The airway epithelium plays an essential role in innate immunity to lung pathogens. Ribonucleoprotein particles primarily composed of major vault protein (MVP) are highly expressed in cells that encounter xenobiotics. However, a clear biologic function for MVP is not established. We report here that MVP is rapidly recruited to lipid rafts when human lung epithelial cells are infected with Pseudomonas aeruginosa, and maximal recruitment is dependent on bacterial binding to the cystic fibrosis transmembrane conductance regulator. MVP was also essential for optimal epithelial cell internalization and clearance of P. aeruginosa. These results suggest that MVP makes a substantial contribution to epithelial cell-mediated resistance to infection.     

Reversible concerted ligand substitution at alternating metal sites in an extended solid

We report a synthetic material, [Co2(bipy)3(SO4)2(H2O)2](bipy) (CH3OH), (1, where bipy = 4,4'-bipyridyl) that contains discrete reactive and inert structural motifs that undergo a reversible substitution reaction involving the concerted and spatially controlled introduction of bipyridine and methanol molecules at the reactive sites. This reaction defines the pore geometry of the resulting open-framework structure and controls the manner in which this structure sorbs small molecules. The molecules involved in the reaction are positioned by an array of well-defined interactions during their path to binding to the metal centers.     

Strengthening understanding and perceptions of mineral fertilizer use among smallholder farmers: evidence from collective trials in western Kenya

It is widely recognized that mineral fertilizers must play an important part in improving agricultural productivity in western Kenyan farming systems. This paper suggests that for this goal to be realized, farmers’ knowledge must be strengthened to improve their understanding of fertilizers and their use. We analyzed smallholder knowledge of fertilizers and nutrient management, and draw practical lessons from empirical collective fertilizer-response experiments. Data were gathered from the collective fertilizer-response trials, through focus group discussions, by participant observation, and via in-depth interviews representing 40 households. The collective trials showed that the application of nitrogen (N) or phosphorous (P) alone was insufficient to enhance yields in the study area. The response to P on the trial plots was mainly influenced by incidences of the parasitic Striga weed, by spatial variability or gradients in soil fertility of the experimental plots, and by interactions with N levels. These results inspired farmer to design and conduct experiments to compare crop performance with and without fertilizer, and between types of fertilizers, or responses on different soils. Participating farmers were able to differentiate types of fertilizer, and understood rates of application and the roles of respective fertilizers in nutrient supply. However, notions were broadly generated by unsteady yield responses when fertilizers were used across different fertility gradients, association with high cost (especially if recommended rates were to be applied), association of fertilizer use with hybrids and certain crops, historical factors, among other main aspects. We identified that strengthening fertilizer knowledge must be tailored within existing, albeit imperfect, systems of crop and animal husbandry. Farmers’ perceptions cannot be changed by promoting more fertilizer use alone, but may require a more basic approach that, for example, encourages farmer experimentation and practices to enhance soil properties such as carbon build-up in impoverished local soils.