Life Sciences Commons^™

Apoptosis Of Rat Myoblasts Is Induced In Vitro By Late, But Not Early, Wound Fluids, Raymond E. Sicard, Linh Nguyen, John Menezes

Journal of the Minnesota Academy of Science

Interstitial fluids from late wound repair environments are not "regeneration permissive" as judged by their inability to promote either proliferation or differentiation of myoblasts in vitro. This irwestigation considered whether apoptosis (induced death) was an alternative fate for myoblasts exposed to these interstitial fluids. Myoblast fate was assessed by cell counts, tritiated thymidine release, and propidium iodide staining. Fluids from early wounds increased mean cell counts and induced little thymidine release or propidium iodide labeling. In contrast, fluids from late wounds reduced cell counts and induced both thymidine release and propidium iodide labeling. These data suggest that interstitial fluids from …

Regeneration - The Road Not Taken, Raymond E. Sicard

Journal of the Minnesota Academy of Science

Regeneration and repair are mutually-exclusive, adaptive responses to injury. The events associated with each process are well characterized. However, cellular and molecular mechanisms for their regulation are only now beginning to be defined. Moreover, full appreciation for factors that predispose to these contrasting pathways is not yet available. This article presents a perspective on regeneration and repair that suggests specific relationships between these modes of responding to injury. Injury provokes a coordinated pattern of response to tissue damage. At the wound site, local events determine whether tissue restoration or replacement occurs. Interplay among parenchymal and stromal cells at the site …

Regenerative Biology: New Tissues For Old, David L. Stocum

Journal of the Minnesota Academy of Science

Throughout the human life cycle, tissues are regenerated either continuously to maintain tissue integrity in the face of normal cell turnover or in response to acute or chronic damage due to trauma or disease states. Blood, epithelia of skin and tubular organs, hair and nails, and bone marrow are examples of human tissues which regenerate continuously as well as in response to damage. Bone, muscle, adrenal cortex and kidney epithelium also regenerate in response to damage, and bone is continually remodeled in response to stress vectors.

The response of many other vital tissues to damage, however, is not regeneration but …

Wound Repair, Raymond E. Sicard, Jeffry D. Shearer, Michael D. Caldwell

Journal of the Minnesota Academy of Science

Following injury, a series of events is initiated that includes global and local reactions. Global reactions, such as inflammatory and immunological responses as well as adjustments in neural and endocrine status, are directed at marshaling the organism's resources for dealing with changes in its integrity and the potential threat of infection or other complications. Injury entails cell and tissue damage and often a physical breach in the barrier against the outside world (e.g., skin). Local reactions are exemplified by immediate hemostatic (e.g., blood clotting) events followed by changes in local cellular composition created by the inflammatory infiltrate and adjustments in …

Perspectives On Liver Regeneration, Janeen H. Trembley, Clifford J. Steer

Journal of the Minnesota Academy of Science

No abstract provided.

Tissue Engineering: At The Interface Between Engineering, Biology And Medicine, Brenda Ogle, Priti Gairola, Jodi Balik, Daniel L. Mooradian

Journal of the Minnesota Academy of Science

No abstract provided.

Vascular Endothelial Cell Growth Factor Expression In Endothelial Cells Is Induced By Mechanical Wounding, Paul J. Sammak, Phuong Oanh Tran, Timothy A. Olson

Journal of the Minnesota Academy of Science

Endothelial cell motility is central to several biological processes including angiogenesis during wound healing, reendothelialization of vessel walls after damage and neovascularization of tumors. However, control mechanisms that stimulate and inhibit cell movement are not known. Our objective is to understand the signals that initiate movement of endothelial cells. To examine these questions, we used an in vitro wound model of quiescent pulmonary artery endothelial cell monolayers which were stimulated to move by mechanical injury. Ca2+ signaling at the time of wounding produces long lasting effects on cell movement. We investigated whether new gene transcription after wounding might also stimulate …

Basic Fibroblast Growth Factor And Hepatocyte Growth Factor Content Of Wound, Repair, And Muscle Regeneration Fluids, Raymond E. Sicard, Wendy A. Mand

Journal of the Minnesota Academy of Science

Injury produces marked changes to the local environment. Changes in both diversity and availability of bioactive substances at wound sites might discriminate between repair and regeneration microenvironments and selectively drive events leading to final resolution. Among factors with potential relevance to wound repair and regeneration are basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF). In this study, concentrations of these factors were determined in fluids derived from wound, repair, and regeneration-conditioned models using enzyme-linked immunosorbent assays. All fluids contained substantial concentrations of bFGF which rose 5- to I 5-fold as resolution to injury was achieved. Mean bFGF content …

Radiant Rewarming For Hypothermia: Pilot Canine Study Model, Linda M. Shecterle, John A. St. Cyr

Journal of the Minnesota Academy of Science

The purpose of this feasibility study was to determine if a radiant heat device could be used to rewarm hypothermic canines. Twenty canines were first cooled to varying degrees of hypothermia and then rewarmed. An ice water bath was used to create mild (> 32' C), moderate (29 to 32' C), or severe ( < 29· C) hypothermia, as assessed by measuring the animal's core body temperature. Two radiant heat devices, an IAD450 animal device or a thermal recovery unit (TRU), suitable for humans, were used for rewarming animals. There were no deaths or lasting significant complications during the treatment or follow up interval. Rewarming rates were: mild- 2.2· C during the first hour and 4.9' C during the second hour, moderate- 2.1" C during the first hour and 5.5' C during the second hour, or severe- 0.8' C during the first hour and 4.4' C during the second hour and 4.1' C during the third hour. Rewarming rates were comparable in either mild or moderate hypothermic conditions, however, in the severely hypothermic state, a slower rate of rewarming occurred during the first hour. Both devices proved capable of rewarming animals within acceptable time frames with no lasting clinically significant toxicity. Data accumulated and monitoring done during this study included: complete blood count, serum chemistries, blood gases, physiological hemodynamic parameters, and multiple temperature site assessment. This technique should be further explored as an alternative method of rewarming from a hypothermic to a normothermic state.

Translational Coupling Of Pseudomonas Aeruginosa Phna And Phnb Genes In Escherichia Coli, Patrick L. Splinter, David W. Essar

Journal of the Minnesota Academy of Science

Pseudomonas aeruginosa has two anthranilate synthase (AS) gene pairs. One AS enzyme participates in tryptophan synthesis; its genes are designated trpE and trpG The other AS enzyme, encoded by phnA and phnB, participates in the synthesis of pyocyanin, the characteristic phenazine pigment of the organism. The phenazine pathway genes phnA and phnB overlap by 23 base pairs, excluding the phnB Shine-Dalgarno region, with pbnA upstream from phnB. Our objective was to examine the cloned P. aeruginosa phnA and pbnB gene pair for translational coupling in Escherichia coli. The first 113 base pairs of phnB were fused with either LacZ or …

The Distribution Of Minnesota Fishes And Late Pleistocene Glaciation, James C. Underhill

Journal of the Minnesota Academy of Science

No abstract provided.

Mercury In Fish From Northeastern Minnesota Lakes: Historical Trends, Environmental Correlates, And Potential Sources, Edward B. Swain, Daniel D. Helwig

Journal of the Minnesota Academy of Science

ABSTRACT-High mercury concentrations in fish of some Minnesota lakes and rivers were first noted in 1971. Major anthropogenic sources of mercury to Minnesota rivers generally have been identified and controlled, but it has been difficult to identify mercury sources to remote northeastern Minnesota lakes containing fish with elevated mercury levels. Analysis of sediments from these lakes suggests that mercury deposition has increased by a factor of about 3.5 since white settlement in the state. Because the increase is spatially constant across northeastern Minnesota, atmospheric pollution appears to be responsible for the increase. Given that fish mercury varies considerably among lakes, …

The Itasca State Park Algal Culture Collection At Loras College, David B. Czarnecki, M. Jon Ross

Journal of the Minnesota Academy of Science

A list of over 125 algal cultures originating from Lake Itasca State Park is presented. These cultures, permanently housed at Loras College, Dubuque, Ia., include 115 taxa representing 68 genera from six algal Divisions. Approximately one-third of the taxa are desmids.

The Diatom Flora Of The Red Lake Peatland, Minnesota, Thomas P. Pienkowski, Daniel E. Wujek

Journal of the Minnesota Academy of Science

Diatoms collected from three transects in the Red Lake Peatland occur in characteristic assemblages. One hundred two taxa were observed from 26 sample sites, with Eunotia exigua and Pinnularia rupestris the most dominant species. Clustering indicated three peatland types were present: rich fen, transitional and poor fen, and bog.

Ecological And Evolutionary Considerations Of Large Scale Mosquito Control Programs, Harrison B. Tordoff

Journal of the Minnesota Academy of Science

No abstract provided.

Association Of Dna With Nuclear Estradiol Receptors Released From Chromatin, Thresia Thomas, Benjamin S. Leung

Journal of the Minnesota Academy of Science

A cell-free system was established to study the role of steroid hormones In transcriptional control. The system consists of hormone-receptor-chromatin complex formation using partially purified receptor and chromatin. Micrococcal nuclease digestion of the complex released a 7S form of receptor. The absorbance at 260 nm also showed a peak in the 7S region of the sucrose gradient. DNAase I digestion caused the 7S receptor to shift to 2.8S form, while RNAase had no effect. When the receptor-chromatin complex was digested with DNAase I, different forms of receptors were observed, depending on the digestion time. Digestion of one minute produced a …

Effects Of Various Hormones On Human Carcinoma Cell Proliferation, Y. L. Gao, B. S. Leung, A. H. Potter, W.C.Y. Yu

Journal of the Minnesota Academy of Science

Cell proliferation of a mammary adenocarcinoma cell line, CAMA-1. is affected by a number of steroid hormones and prolactin in long-term cultures. Estrogenic compounds stimulate cell growth while antiestrogenic compounds inhibit it. Prolactin can synergize the estrogenic effect. Progesterone, glucocorticoid or androgen reduce cell proliferation. Dihydrotestosterone is a very potent inhibitor,- effective at as low as 10 nM, and its effect is independent of estrogen action. Cortisol is a less effective inhibitor at concentrations below 10 nM; at these levels cortisol exhibits a slight inhibition which appears to be unrelated to estrogenic action. However, at higher concentrations, cortisol markedly reduces …

Scaled Chrysophyceae From Lake Itasca Region. Ll. Synura, Chrysophaerella, Spiniferomonas, Daniel E. Wujek, Michael M. Weis, Robert A. Andersen

Journal of the Minnesota Academy of Science

Using electron microscopy, 49 plankton samples from the Lake Itasca region were examined for the silica-scaled chrysophycean genera Synura, Chrysosphaerella and Spiniferomonas. Twelve taxa were observed: five are new for Minnesota, and two of these, Synura multidenta and Synura petersenil f. asmundiae, are new reports for the continental United States.

Association Of Aquatic Insects To Macrophytes In An Agricultural Drainage Ditch, Kevin King, John Flypaa, Henry W. Quade

Journal of the Minnesota Academy of Science

The aquatic insects associated with five species of aquatic macrophytes were collected and identified from a drainage ditch in Le Suer County. A total of 21,160 specimens from eight orders were recovered with Diptera being the dominant. Tests of association, using the Coefficient of Community and Percent Similarity revealed a unique community associated with Potamogeton nodosus. Further, the authors found that the same information generated from the study could have been accomplished without the detailed taxonomy.

Circadian Rhythms In Blood And Self-Measured Physiologic Variables In Young People Ages 9-14, Joseph Rabatin

Journal of the Minnesota Academy of Science

In order to investigate circadian (about 24 hour) rhythms in young people 9-14 years of age in several physiologic variables, self-measurements of oral temperature, pulse, blood pressure and selected performance tests were conducted by ten subjects. Each subject was also 'hospitalized for a twenty-four hour span in order to have blood sampled to detect a circadian rhythm in several blood constituents and indices.

Occurrence Of Corbicula Manilensis Phillipi In The Lower Minnesota River, Steven E. Cummings, James A. Jones

Journal of the Minnesota Academy of Science

On March 2, 1978, several empty shells of the fresh water clam, Corbicula manilensis Phillipi, were collected in the Minnesota River near the Blackdog electric generating plant in Burnsville, Minnesota. Since this Asiatic species was first observed in America in 1935, it has spread into all major river systems of North America. Its northernly extension in the Mississippi River system was, however, thought to end in northeast Iowa and to exclude Minnesota. Occurrence of this species is a potential liability because it often exerts a disruptive influence in the community that it invades.

Dictyostelium Discoideum's 35-Year Contribution To Growth Of Biology: A Bibliometric Analysis, Joann Hilmas, Walter Fluegel

Journal of the Minnesota Academy of Science

Biological Abstracts is a sufficiently adequate bibliometric tool for the analysis of the accumulated literature of certain organisms. Dictyostelium discoideum (Cellular slime mold) titles are scarce, yet literature growth parallels some of the same growth patterns as the whole of science. Relatively few (5 percent) biologists produce most (55 percent) of the literature on this organism. American authors predominate. The literature is grouped into various categories such as aggregation, cytology, growth, and genetics with the molecular-physiological works surpassing all other categories combined in the last 5 years (66 percent). Although the literature is scattered worldwide, most articles are found in …

Rotifers In Lake Itasca, Judy Helgen

Journal of the Minnesota Academy of Science

Rotifers were collected from both the Littoral and Limnetic zones in Lake Itasca, Clearwater County, Minnesota, during two weeks in midsummer. In total, 82 species of rotifers were found, and 69 were identified to species. The littoral zone produced 67 species of rotifers, primarily associated with the aquatic macrophytes. While 35 species were collected in the limnetic zone, only 13 of them were restricted to that habitat. Species are listed by habitat and by type of plant on which they occurred.

An Electrophoretic Study Of Caecal Proteins Of Clinostomum Marginatum (Trematoda), Dale E. Greenwalt, Harold A. Borchers

Journal of the Minnesota Academy of Science

Whole-worm extracts of Clinostomum marginatum were subjected to polyacrylamide gel electrophoresis. Gels of early stage metacercariae, late-stage metacercariae and adult worms contained 26,24, and 27 protein bands respectively. The protein band patterns of the three stages were similar except for 1) a hemoglobin band in gels of adult extracts and 2) a large increase in the quantity of four anodic bands of late-stage gels. The proteins constituting these four bands were present in the caecal contents of late-stage metacercariae . These same proteins were also found in metacercarial cysts as part of an exuded material left behind by the fluke …

Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere

Journal of the Minnesota Academy of Science

A preliminary report of the aquatic Ascomycetes of Lake Itasca, Minnesota. Included is an introduction, methods of harvesting and studying, a key, descriptions, and illustrations of 19 common ascomycetous fungi inhabiting the study area .

Experimentally-Induced Muscle Atrophy In The Developing Chick Embryo: Glycogen Metabolism, Michael J. Harris

Journal of the Minnesota Academy of Science

Glycogen content and the activities of phosphorylase (PHRL) and glycogen synthetase (GS) in the hind limb muscle of normal, unilaterally (right) - denervated and in nicotine sulfate (NS) - injected chick embryos were determined to assess the effect of the experimental treatments on glycogen metabolism. Glycogen content increased with increase in age in normal limbs, remained relatively low in denervated limbs, increased with age in left (unoperated) limbs of denervated embryo limbs at a rate lower than normal except between days 13 and 17 of incubation, when glycogen content tripled. The same parameter in NS-injected embryo limbs remained generally low …

Some Effects Of The Bite Of The Short-Tailed Shrew, Blarina Brevicauda, Howard F. Krosch

Journal of the Minnesota Academy of Science

Folklore, especially in Europe, has long maintained that shrews are extremely poisonous. Zoologists have discounted this belief as superstition until recently, when it was learned that at least two species of shrews - the European water shrew, Neomys fodiens, and the American short-tailed shrew, Blarina brevicauda - produce a toxin in their sub-maxillary glands.

A Floristic Study And Grouse Production In The Mille Lacs Wildlife Area, Michael J. Scanlan

Journal of the Minnesota Academy of Science

The upland vegetation in four stands was analyzed for differences in conditions important for ruffed grouse production. The structure of the control stand suggests that Acer saccharum and other shade-tolerant tree species will replace the dominants Quercus borealis and Populus tremuloides. The Acer saccharum would not be useful to grouse. In an adjacent stand in which forest litter had been burned, there was a tremendous amount of reproduction of trembling aspen and much less sugar maple reproduction, compared with the control stand. Differences in the understory beneficial to grouse also were found.

Fishes Of The Yellow Medicine River In Southwestern Minnesota, Carl H. Ernst

Journal of the Minnesota Academy of Science

In view of the possible impoundment of the Yellow Medicine River in southwestern Minnesota by a proposed United States Army Corps of Engineers dam, a survey of the fish-fauna of this river was undertaken. The fish-fauna is listed and discussed, as are also the possible effects of the impoundment.

Migration And Mortality Of Banded Mourning Doves, Lawrence L. Thomforde

Journal of the Minnesota Academy of Science

Banding data gathered over a three-year period at Savage, Minnesota, were analyzed to determine migration patterns and mortality rates of 2,218 mourning doves. The age ratio among trapped doves was 1.19 immatures per 1 adult and the sex ratio 3.84 males per 1 female. The weighted mean annual mortality rate for immature doves was 58.5 percent. For adult doves, the weighted annual mortality was 28.2 percent. The total weighted recovery rate was 1.24 immatures to 1 adult. The data show that immatures are 75 percent more vulnerable than adults to being shot; although no difference was found in direct recovery …