Drought effects on the dynamics of leaf production and senescence in field-grown Medicago arborea and Medicago citrina

Forage shrub production in the Mediterranean region is frequently limited by soil water availability. To study plant responses to water deficit under such conditions is important for improving crop management and for selecting better yielding forage shrub species. Pre-dawn leaf water potential (Ψ_pd), plant leaf area (PLA), leaf area per stem (LA_s), leaf appearance rate (LAR₁;), leaf senescence rate (LSR), individual leaf area (LA) and maximal leaf elongation rate (LER) were studied throughout the year for Medicago arborea (MA) and Medicago citrina (MC) under irrigated (control) and low rainfall field conditions, at the experimental field site of the University of the Balearic Islands in Spain. With irrigation, the highest LA and LER were observed in autumn and spring and the lowest in winter and summer. LAR; was similar for both species in autumn and winter. Throughout the spring, LAR₁ was higher for MC compared to MA. PLA was similar for both species during the autumn, winter and spring seasons; however, during the summer PLA of MA was significantly reduced by 53%. This decline was attributed to higher leaf senescence during seed maturity. As a consequence, MC maintained higher leaf area (∼ 5 m² plant⁻¹) than MA (3 m² plant⁻¹). Under natural field conditions, soil water deficit increased from February to late August. The main effect of water stress was a marked reduction in LAR₁, LA and LER reflected in lower LA_s and PLA. Leaf area was severely reduced for both species during the summer, but much more intensively in MA, which developed full leaf senescence. Thus, MC maintained higher PLA than MA (0.5 m² compared to 0.0 m²). Throughout the year, but especially in the driest months, MC was superior to MA in leaf growth parameters and PLA.     

Effect of different soil and clove treatments in the control of white rot of garlic

Soil solarisation was consistently efficacious in reducing inoculum density to undetectable levels in a field naturally‐infested with Sclerotium cepivorum. This treatment delayed epidemic onset of white rot of garlic 2–3 months as compared with the untreated control or the inoculation of planting furrows with Glomus intraradices. Furthermore, significant reductions of disease incidence and of the standardised AUDPC were also observed in solarised plots, resulting in quantitative and qualitative yield improvement. Similar effects were observed in plots planted with tebuconazole‐treated cloves, confirming previous results, whereas Trichoderma harzianum was ineffective as a biocontrol agent, when applied to planting furrows. The inoculation of plots with G. intraradices before planting, in three consecutive years, was neither effective for disease control nor on the development of garlic, although the root systems of garlic plants from all the experimental treatments were heavily mycorrhizal at harvest, indicating the presence of native arbuscular mycorrhizal propagules in the soil and their survival after soil solarisation.     

Laser stimulation of the acupoint ‘Zusanli’ (ST.36) on the radiopharmaceutical biodistribution in <Emphasis Type="BoldItalic">Wistar</Emphasis> rats

Laser used to stimulate acupoints is called laser acupuncture (LA). It is generally believed that similar clinical responses to manual acupuncture can be achieved. Here we analysed the effects of the laser (904 nm) at the ‘Zusanli’ acupoint (ST.36) of the stomach meridian on the biodistribution of the radiopharmaceutical Na^99mTcO₄. Wistar rats were divided into control (CG) and experimental groups (EG). The EG were exposed daily to the laser (904 nm) at ST.36 with 1 joule/min (40 mW/cm²) for 1 min. The animals of the CG were not exposed to laser at all. On the 8th day after LA, the animals were sedated and Na^99mTcO₄ was administered. After 10 min, the animals were all sacrificed and the organs removed. The radioactivity was counted in each organ to calculate the percentage of radioactivity of the injected dose per gram (%ATI/g). Comparison of the %ATI/g in EG and CG was performed by Mann-Whitney test. The %ATI/g was significantly increased in the thyroid due to the stimulation of the ST.36 by laser. It is possible to conclude that the stimulation of ST.36 does lead to biological phenomena that interfere with the metabolism of the thyroid.     

Wildlife detector dogs and camera traps: a comparison of techniques for detecting feral cats

A major challenge in controlling overabundant wildlife is monitoring their populations, particularly as they decline to very low density. Camera traps and wildlife detector dogs are increasingly being used for this purpose. We compared the cost-effectiveness of these two approaches for detecting feral cats (Felis catus) on two pastoral properties in Hawke's Bay, North Island, New Zealand. One property was subject to intensive pest removal, while the other had no recent history of pest control. Camera traps and wildlife detector dogs detected cats at similar rates at both sites. The operating costs of each method were also comparable. We identify a number of advantages and disadvantages of each technique, and suggest priorities for further research.     

Organization of fusicoccin receptor in higher plant plasma membrane: relationship between affinity and molecular mass

Higher plant plasma membranes carry receptors of different affinity for the phytotoxin fusicoccin. Reception of fusicoccin involves proteins belonging to the highly conserved 14-3-3 family, but the complete structure of the fusicoccin receptor (FCR) is unknown. Using radiation inactivation analysis, we estimated the molecular masses of low-affinity and high-affinity FCR at 63 +/- 7 and 130 +/- 15 kD, respectively. The dose dependences of receptor inactivation indicate that microsomal specimens contain "silent" FCRs of 420 +/- 90 kD in amounts commensurate with that of the active FCRs. Both low- and high-affinity FCRs are inactivated by hydrolytic enzymes from the outer surface of the plasma membrane, and impairment of protoplast integrity causes an irreversible transition of the low-affinity binding site into the high-affinity one. A scheme is proposed for the organization of different types of FCR in the plasma membrane, implying that the membrane affinity for fusicoccin reflects the interaction between proteins in the FCR complex.     

Production via good manufacturing practice of exofucosylated human mesenchymal stromal cells for clinical applications

Background

The regenerative and immunomodulatory properties of human mesenchymal stromal cells (hMSCs) have raised great hope for their use in cell therapy. However, when intravenously infused, hMSCs fail to reach sites of tissue injury. Fucose addition in α(1,3)-linkage to terminal sialyllactosamines on CD44 creates the molecule known as hematopoietic cell E-/L-selectin ligand (HCELL), programming hMSC binding to E-selectin that is expressed on microvascular endothelial cells of bone marrow (BM), skin and at all sites of inflammation. Here we describe how this modification on BM-derived hMSCs (BM-hMSCs) can be adapted to good manufacturing practice (GMP) standards.

Andrenocorticotropin and β-lipotropin in the hypothalamus

Adrenocorticotropin and β-lipotropin (β-LPH) have been localized by immunoperoxidase methods in nerve cells and fibers of the hypothalamus and brain stem of the ewe. 6-μm sections were immunostained first for either ACTH or β-LPH. The reaction products and the antibody complexes were then eluted completely from the tissue, and the same section was immunostained for the second peptide. Absorption of the primary antisera with a variety of peptide fragments of ACTH and β-LPH demonstrated, immunocytochemically as well as by radioimmunoassay, that the ACTH and β-LPH antisera were directed to the COOH- and NH(2)-termini of the peptides, respectively. Neither antiserum recognized any portion of the heterologous peptide. In the sequential staining procedure on the same tissue section, preincubation of the antisera with the homologous peptide abolished the staining, whereas preincubation with the heterologous peptide did not affect it, regardless of the order followed. Every nerve cell in the arcuate nucleus that contained ACTH also contained β-LPH, but β-LPH cells appeared, probably falsely, to be twice as numerous as ACTH cells. β-LPH-positive fibers in and beyond the hypothalamus were also more numerous and stained more intensively than ACTH fibers. The salient exception was fibers in the infundibular zona externa, where the opposite was true. Our observations establish that ACTH and β-LPH are contained in the same nerve cells They stongly favor biosynthesis in brain, probably from a common precursor molecule, as has been demonstrated in the pituitary gland. The complexity of the cytologic distribution pattern described suggests that the two peptides are not processed in the same manner by the nerve cell.     

Evolutionary Implications of Persistence Hunting: An Examination of Energy Return on Investment for !Kung Hunting

Hominins are smaller, slower, and weaker than most large mammals, yet they have been eating meat from freshly killed large mammals since before the invention of sophisticated weaponry. It is thought that they could have achieved this seemingly impossible feat through persistence hunting, a practice powered by endurance running. Essentially, one or more hunters pursue a prey animal in the heat of the day until it reaches the point of hyperthermia. This allows a hunter to safely kill the weakened animal at close range using methods such as beating, strangling, or spearing. The energy balance of this approach to getting food is controversial and has not been calculated previously. We examined the energy costs and gains of persistence hunting through several energy returned on investment (EROI) calculations based on synthesizing available field and laboratory data on the energy used by the hunters and the energy returned from the greater kudu (Tragelaphus strepsiceros). We estimate that the EROI of these hunter-gatherers hunting a kudu ranged from 26:1 to 69:1. The net energy gained from such an effort would sustain an average sized !Kung family for 6.7 to 11.2 days. The “profit” energy within these ranges would have supported the early human societies that practiced persistence hunting, contributing to the often-noted “leisure” characterizing many foraging societies (Sahlins 1974).