Effects of Escherichia coli endotoxin on leukocyte and platelet counts, fibrinogen concentrations, and blood clotting in colostrum-fed and colostrum-deficient neonatal calves

Effects of a single IV injection of Escherichia coli endotoxin on hemogram and clotting function were compared in colostrum-fed and colostrum-deficient neonatal calves. Before endotoxin administration, the 2 groups of calves only differed in their prothrombin times. After endotoxin administration, there were significant differences (P less than 0.005) between colostrum-fed and colostrum-deficient calves in total leukocyte, segmented neutrophil, nonsegmented neutrophil, and lymphocyte (P less than 0.05) counts and partial thromboplastin time. Significant time dependent changes were observed in the aforementioned parameters and in platelet count and fibrinogen concentration. Seemingly, colostrum feeding improved the calf's ability to respond to endotoxin challenge exposure probably because of improved granulopoietic activity.     

Coordination polymers of osmium: the nature of osmium black

The design of cytochemical reagents that yield osmiophilic products from which an osmium black may be derived on exposure to osmium tetroxide has resulted in new methods described previously for the ultrastructural demonstration of enzyme activity and functional groups of macromolecules with the electron microscope. Attempts to determine the nature of the osmium black end products have been frustrated by their insolubility. The preparation of watersoluble analogs and their characterization as polymers suggest that the insoluble osmium blacks are coordination polymers. This is consonant with the unusually favorable properties of osmium black in electron microscopy. Although polymers of osmium have frequently been postulated as the end products of reaction of osmium tetroxide with tissue conistituents or with other organic compounds, this is the first example of their characterization.     

Fine Structure and Peroxidase Activity of the Bovine Mandibular Gland Cells

The acini of the bovine mandibular gland consist of mucous and demilunar seromucous cells. The mucous cells contain electron-lucid mucigen droplets or mucoid masses, only rarely delimited by membranes. The cisternae of the RER communicate freely. Mitochondria are scarce. The seromucous demilunar cells contain considerably more granules, and perigranular membranes are far more common. Many granules have characteristic alternating electron opaque and less electron dense areas. The prominent RER appears to be associated with a peculiar labyrinth of interconnecting tubules. Mitochondria are numerous. Numerous myoepithelial cells are observed. The cuboidal cells of the intercalated ducts lack signs of secretory activity. The columnar cells of the striated ducts have extensive infoldings of the basal plasma membrane, associated with mitochondria. The cell apex contains many granulated vesicles. Endogenous lactoperoxidase activity could be demonstrated only in the demilunar cells, within the secretory granules, the RER, including the perinuclear cisternae, as well as the labyrinth mentioned above. A positive reaction could be observed over acinar lumina and in intercellular canaliculi. The possible role of peroxidase as a component of a bactericidal system of the bovine saliva is discussed.     

Lactic dehydrogenase and metabolism of human leukocytes in vitro

During transformation and division of lymphocytes in culture, the lactic dehydrogenase isozymes migrate increasingly toward the cathode. With extension of the time in culture, the mitotic index declines, and the isozyme pattern reverts to dominance of those bands that move toward the anode, despite the cellular tendency to anaerobic metabolism. These findings suggest that synthesis of the more slowly migrating lactic dehydrogenase isozymes in this system is related to mitotic activity, and not to the aerobic or anaerobic conditions of cell culture.     

Something to be done: treating HIV/AIDS. River Path Associates

Largely because of disparities in access to drug treatment and care, AIDS morbidity and mortality have fallen in the developed world but continue to rise among developing countries. Achieving more equitable access to AIDS drugs is hindered by high drug prices, technical complexities related to the provision of health care, and conflict among stakeholders. Recognition that health is vital to the prospects of the emerging global society must be combined with new mechanisms to help all stakeholders work together cooperatively. Tiered drugs pricing should be coupled with investment in health services. An independent "Global Task Force," able to act as an "active think tank," could build consensus about the way forward.     

Drones detect illegal and derelict crab traps in a shallow water estuary

The issues surrounding illegal, unregulated and unreported fishing, and that of abandoned, lost and discarded fishing gears, leading to ghost fishing, are intensifying. Estuarine crab trapping is likely subject to high levels of illegal and potential ghost fishing, because it also has good economic incentives regarding potential catch, low gear acquisition costs and accessible fishing grounds. To improve the efficiency and effectiveness of fisheries monitoring, control and surveillance operations, the efficacy of small consumer‐grade drones for sighting traps in an estuary in NSW, Australia, was tested. Twelve sets of two flights were undertaken at 20 and 30 m altitude over a 600‐m stretch of estuary for 5 days to quantify the detectability of submerged mesh traps of three different mesh colours. The drone was able to detect the majority of traps efficiently, with depth in relation to water clarity being the main factor affecting detection. In shallow water, detection rates were high for all mesh colours, but in the slightly deeper placements, orange traps were more readily detected. This study demonstrates that drones could be an efficient and reliable tool for rapidly assessing areas for illegal and derelict traps and can be supplemented into land or vessel‐based fisheries operations.     

Efficiency of a novel biodegradable pyrolysis liquid-amended mulch in weed control

Agrochemicals and plastics represent a burden on natural ecosystems and there is an urgent need to introduce alternative plant protection measures that have fewer negative impacts on the environment. Replacement of plastic mulches and synthetic pesticides with their biodegradable alternatives offers a way to decrease chemical residues. Pyrolysis liquids (PL) have been suggested as easily degradable and residue-free herbicides for agriculture. We tested the efficiency of PL (1%–10% of volume) containing peat mulch (PLM) in weed control under glasshouse and field conditions. We also estimated the length of the withdrawal period needed between PLM spreading and sowing/planting for crops and examined the light permeability and effects of PLM on soil temperature. In the glasshouse, the mulch amended with 5%–10% PL inhibited weed germination entirely. In the agricultural field, the number of weeds remained 44%–60% lower under PLM than under the control mulch. In a study performed in a city park, weed cover around the base of trees remained 64%–85% lower under PLM than without a mulch. However, a 7–21 d withdrawal period, depending on crop plant species, is needed to avoid injuring the crops. PLM inhibited sunlight effectively and the effects on soil heat sum across the growing season remained small. The weed-inhibiting effect of PLM is probably a result of both the PL compounds and the solid cover, formed by the sticky PL and peat fibres, which acts as a mechanical barrier. We conclude that the PLM is a promising alternative to plastic mulches.