A rationale for administering leukocyte endogenous mediator to protein malnourished,hospitalized patients

Leukocyte endogenous mediator is a low molecular-weight protein synthesized by circulating monocytes and fixed macrophages of the reticuloendothelial system. Exogenous administration of leukocyte endogenous mediator to a well-nourished animal stimulates both specific and nonspecific immune function and replicates the protein metabolic response to infection, characterized by fever and increased amino acid oxidation, skeletal protein degradation and synthesis of “acute-phase” proteins. Leukocyte endogenous mediator administration also affords protection against semilethal doses of bacteremia in the well-nourished animal.In the protein-depleted host, synthesis or release of leukocyte endogenous mediator in response to infection appears to be reduced and the attenuated metabolic response may be attributed, in part, to a deficit in its production. However, nutritional repletion of the malnourished patient results in restoration of the capacity to produce leukocyte endogenous mediator usually within three to seven days, if adequate dietary protein is provided.Since protein malnutrition is associated with increased incidence and severity of bacterial infections, we postulate that the reduced synthesis and/or release of leukocyte endogenous mediator in protein malnutrition is detrimental. In those critically-ill, malnourished patients who cannot endogenously synthesize leukocyte endogenous mediator, and for clinical reasons cannot be repleted rapidly or are already infected and/or undergoing operative stress, exogenous administration of leukocyte endogenous mediator should be considered along with nutritional support. Administration of this protein to a seriously-ill malnourished individual should produce a metabolic profile of fever, increased urinary nitrogen excretion and falls in serum albumin concentrations that are generally considered pathologic. However, administration of leukocyte endogenous mediator over short periods of time should also provide the anabolic impetus for the augmented synthesis of proteins beneficial to recovery. In most cases, these countervailing forces of anabolism and catabolism should be of benefit to the host if the response to infection and injury is viewed as a physiologic redistribution of endogenous nutrients to meet the more critical and immediate needs of the stressed patient.     

Cell polarity in precartilage mouse limb mesenchyme cells

The patterns of orientation of individual mesenchyme cells have been evaluated in the hindlimb of the mouse embryo during the period of transition from early aggregation (Day 12) to cartilage formation (Day 13). Orientation was measured by determining the angular relationship between the Golgi-nucleus axis of each cell relative to either the longitudinal limb axis or the center of the cartilaginous aggregate. Patterns were assessed qualitatively and quantitatively in horizontal, vertical, and transverse sections of the proximal, middle, and distal precartilage mesenchyme. These analyses showed that the mesenchyme cells are oriented predominantly toward the longitudinal axes of both the early (Day 12) and late (Day 13) aggregates.     

Carabid beetle diversity and distribution in Boston Harbor Islands national park area (Coleoptera, Carabidae)

As part of an All Taxa Biodiversity Inventory in Boston Harbor Islands national park area, an inventory of carabid beetles on 13 islands was conducted. Intensive sampling on ten of the islands, using an assortment of passive traps and limited hand collecting, resulted in the capture of 6,194 specimens, comprising 128 species. Among these species were seven new state records for Massachusetts (Acupalpus nanellus,Amara aulica,Amara bifrons, Apenes lucidulus, Bradycellus tantillus, Harpalus rubripes and Laemostenus terricola terricola-the last also a new country record; in passing we report also new state records for Harpalus rubripes from New York and Pennsylvania, Amara ovata from Pennsylvania, and the first mainland New York records for Asaphidion curtum). For most islands, there was a clear relationship between species richness and island area. Two islands, however, Calf and Grape, had far more species than their relatively small size would predict. Freshwater marshes on these islands, along with a suite of hygrophilous species, suggested that habitat diversity plays an important role in island species richness. Introduced species (18) comprised 14.0% of the total observed species richness, compared to 5.5% (17 out of 306 species) documented for Rhode Island. We surmise that the higher proportion of introduced species on the islands is, in part, due to a higher proportion of disturbed and open habitats as well as high rates of human traffic. We predict that more active sampling in specialized habitats would bring the total carabid fauna of the Boston Harbor Islands closer to that of Rhode Island or eastern Massachusetts in richness and composition; however, isolation, human disturbance and traffic, and limited habitat diversity all contribute to reducing the species pool on the islands relative to that on the mainland.     

Scoyenia Escape Burrows in Fluvial Pebbly Sand: Upper Triassic Sugarloaf Arkose,Deerfield Rift Basin,Massachusetts, USA

Late Triassic larvae of an insect, probably a beetle, moved diagonally upwards though fluvial pebbly sand along a thin mud layer, constructing Scoyenia burrows in the Sugarloaf Arkose, Deerfield rift basin, Massachusetts. They may have been escaping a temporary rise of the water table in the monsoonal dry season.     

Reduction and Maintenance of a White-Tailed Deer Herd in Central Massachusetts

Abstract: Controlled public hunts have been used in a variety of settings to reduce overabundant white-tailed deer (Odocoileus virginianus) herds. We present the results of a large-scale (160 km²) controlled hunt at Quabbin Reservation (QR) in central Massachusetts, USA. The QR was divided into 5 hunt zones. Hunting was initiated in each zone from 1991 to 1994 and continued through 2004. The management goal was to achieve posthunt deer densities of4 deer/km². Initial estimated deer densities in each zone ranged from 11.4 deer/km² to 27.6 deer/km². The management goals were reached in each zone after 2-4 years of hunting. Posthunt populations were maintained at or below the goal even though total hunter effort was reduced. Hunters were not required to harvest antlerless deer, but antlerless deer comprised 55-83% of the harvest each year. We simulated the effects of 5 years without hunting on deer populations. The simulated deer population exceeded management goals after 2 years. Our results demonstrate that controlled public deer hunts can effectively reduce deer populations and maintain them at desired levels over large areas with minimal hunter restrictions. Managers should prepare stakeholders during the hunt planning process for the need to continue overall harvest rates of >30% during the maintenance phase of a deer management program.     

The appearance of alpha-crystallin in relation to cell cycle phase in the embryonic mouse lens

Specific protein synthesis in the embryonic mouse lens was studied by immunofluorescence with antisera to adult mouse lens or crystallin fractions. Positive reactions were first detected in a few cells of the lens cup 18-24 hr after contact between optic vesicle and presumptive lens ectoderm had been established. During formation of the lens vesicle a rapidly increasing fraction of cells produced crystallins. At the time of detachment of the vesicle from the surface all cells of its posterior wall showed immunofluorescence. After fiber elongation became distinct cells of the anterior epithelium began to fluoresce and shortly afterwards the entire rudiment produced crystallins. The early reactions were due entirely to the presence of alpha-crystallin. Reactions were restricted to the lens. Thus, in the mouse as in other species crystallins were detectable by immunofluorescence in vivo only after lens morphogenesis was well underway and only in the lens rudiment itself. Cells first synthesizing crystallins always had an elongated shape and their nuclei were in a basal position. A few hours later mitotic cells displayed fluorescence. Taking into account earlier found relations between cell morphology and cell cycle phase, this indicates that alpha-crystallin is first demonstrable in the S-or early G-2 phase of the cell cycle, and that the start of its synthesis does not preclude continued cell replication. It is interesting that the cellular location, cell cycle phase, and developmental stage, in which crystallins first appear, are comparable in mouse and chick embryo. Yet, entirely different proteins are involved: alpha-crystallin in the first, delta-crystallin in the latter. Implications of this for our understanding of lens induction are discussed.     

Problems encountered in measuring erythrocyte pyrimidine 5'-nucleotidase activity

An improved method of two-dimensional electrophoresis that allows unequilibrated first-dimension gels to be loaded and electrophoresed on second-dimension gels twice the length used in the O'Farrell technique has been developed. Normally, the electrophoresis of unequilibrated first-dimension gels on long second-dimension gels with the resolving gel set at pH 8.8 results in poor resolution of low-molecular-weight proteins. Adjusting the pH of the resolving gel to pH 8.3 maintains the low-molecular-weight proteins in a stacked configuration during their migration through the length of the 10% acrylamide gel. Utilization of a 10 to 20% exponential polyacrylamide gradient in a resolving gel set at pH 8.3 separates these low-molecular-weight proteins with excellent resolution. Electrophoretic resolution of protein spots in resolving gels set at pH 8.8 is not as sharp as in gels set at pH 8.3, and resolution progressively deteriorates in gels set at higher pH values.     

The sites of synthesis and the subsequent migration of newly synthesized protein in retina

Radioautographs of rabbit retinas fixed immediately after a 1 or 2 min exposure in vitro to ³H leucine revealed high rates of protein synthesis in receptor cell inner segments, perikarya of ganglion cells, and cells of the inner nuclear layer. If these brieflly labelled retinas were returned to unlabelled medium for periods of up to 6 hr, the radioautographs revealed a progressive dispersion of the labelled proteins from their sites of synthesis. This was largely completed by $\text{1}\text{1}\text{2}$ hr and appeared, in one instance at least, to involve processes other than simple diffusion. Superimposed on the dispersive phenomenon was a process of concentration of the newly formed proteins at two sites quite distant from their synthesis, that was apparent after $\text{1}\text{1}\text{2}$hr. One of these sites was the receptor cell outer segments, as has been previously described, the other was the outer plexiform layer.