Exogenous DNA expression in eukaryotic cells following microinjection.

Microinjection of nucleic acids, DNA, RNA, proteins, and any soluble material into living eukaryotic cells makes it possible to design experiments focused on single cells. In contrast facilitated transfer protocols requires hundreds of thousands of cells from which the expressed gene or intracellular effect must be detected within the culture. In addition to the immediate observable nature of the expressed product and intracellular reaction, microinjection bypasses the uptake toxicity associated with facilitated transfer of foreign material into cultured cells.

Nitrogen and phosphorus availability in composted and uncomposted poultry litter.

Poultry litter applications to land have been based on crop N requirements, resulting in application of P in excess of plant requirements, which may cause degradation of water quality in the Chesapeake Bay watershed. The effect of litter source (the Delmarva Peninsula and Moorefield, West Virginia) and composting of poultry litter on N mineralization and availability of P in two soil types (sandy loam and silt loam) was determined in a controlled environment for 120 d. Nitrogen mineralization (percent total organic N converted to inorganic nitrogen) rates were higher for fresh litter (range of 42 to 64%) than composted litter (range of 1 to 9%).

Mapping child maltreatment: looking at neighborhoods in a suburban county.

This study used administrative data, census data, and geographic information system (GIS) technology to map and analyze the rates and distribution of child physical abuse, sexual abuse, and neglect at the neighborhood level in a suburban jurisdiction. The results provide an example of how administrative data, census data, and GIS technology can give child protective services and community-based agencies a visual tool to help identify and target neighborhoods in which children may be at high risk for maltreatment.

Sequence and expression in Escherichia coli of the coat protein gene of the dwarfing strain of soybean dwarf luteovirus.

The nucleotide sequence of the coat protein gene of the dwarfing (D) strain of soybean dwarf luteovirus (SbDV) was determined from cloned cDNA. The gene contains 600 nucleotides and encodes a protein of 200 amino acids with a calculated molecular mass of 22.2 kDa.

Weak anamnestic responses of inbred mice to Yersinia F1 genetic vaccine are overcome by boosting with F1 polypeptide while outbred mice remain nonresponsive.

The role of immunity to intracellular Ags in resistance to infection by Yersinia is not well established. The enteropathogenic bacteria Yersinia pseudotuberculosis and Yersinia enterocolitica actively translocate Ags to the cytosol of eukaryotic cells. Whereas Yersinia pestis does not always express the requisite cellular adhesins, results have varied as to whether similar cytosolic translocation of Ags occurs in vitro.

Premating and gestational effects of maternal nutrition on secondary sex ratio in house mice.

Pregnant female house mice maintained on a consistent low-food diet give birth to a lower proportion of males than do control females fed ad libitum. Because house mice may experience daily fluctuations in food availability, we tested whether intermittent feeding during gestation influences the sex ratio of the offspring. In addition, we tested whether intermittent feeding has asymmetrical effects on the masses of adult male and female offspring.

The new nutrition facts label in the print media: a content analysis.

A content analysis was conducted to evaluate the coverage of the new food labels in the print media from December 1, 1992, to August 30, 1993. We used newspaper, magazine, and health newsletter indexes to identify 59 newspaper articles, 16 magazine articles, and 7 health newsletter articles for examination. Articles were evaluated by four trained coders using a pretested coding form addressing 35 aspects of the nutrition label coverage.

Gene expression in a temperature-sensitive mutant of the cell cycle.

The proliferative response of mammalian fibroblasts to growth stimulation requires gene expression, including an increase in RNA synthesis. Vimentin, a class III intermediate filament, has been shown to be encoded by a growth-regulated gene whose mRNA levels increase after serum stimulation of quiescent hamster fibroblasts. This induction is a consequence of increased vimentin-specific transcriptional activity and is followed by the accumulation of stable cytoplasmic transcripts which are translated into polymerized filaments.

Review: molecular biology of transgenic animals.

The amazing pace of discovery within the field of molecular biology has expanded the understanding of as well as the potential for genetic engineering in laboratory and domestic animals. Recently, specific techniques have been perfected, including recombinant DNA, genetic cloning, analysis of gene expression, and the sequencing of nucleic acids and proteins. These molecular techniques combined with methods allowing transfer of the recombinant genes into living cells and fertilized eggs advent the production of transgenic mice and other animals, the application of which is unlimited.

Cooperativity of SV40 T antigen and ras in progressive stages of transformation of human fibroblasts.

Human diploid fibroblasts immortalized by SV40 T antigen provide an experimental system for studying the progression and synergism in transformation by secondary oncogenes. We have utilized the human fibroblast line HAL, which was immortalized with an orgin-defective SV40 genome encoding a temperature-sensitive T antigen, to study the cooperativity between SV40 T antigen and the ras oncogene in the progression of transformation. This study demonstrates that HAL cells possess characteristic growth patterns, requiring 10% serum, are anchorage dependent, and express a temperature-sensitive T antigen.

Use of support groups with adult female survivors of child sexual abuse.

Adult survivors of child sexual abuse suffer from a variety of interpersonal and intrapersonal problems. The support group, with its emphasis on self-help and mutuality, represents a potentially powerful form of intervention to assist survivors in dealing with their sexual abuse and the problems resulting from it. In this article, the author explores the use of this form of group work, including the unique role of the group leader, the value of a time-limited approach, the stages of group development, and treatment themes.

Isolation of multiple antibiotic resistant Enterobacteriaceae from river water.

Water samples from the Monocacy River in Frederick County, Maryland, yielded twenty-four isolates which were resistant to tetracycline (TeR, 25 micrograms/ml). Although these organisms were not initially cultured on a coliform-selective medium, twenty-two of the isolates were Gram-negative and carriers of antibiotic resistance to five or more antibiotics; erythromycin, methicillin, novobiocin, penicillin and tetracycline. Of the isolates 45% were biochemically identified as Providencia stuartii; one isolate which contained a 29.