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The Isolation of Friend Virus Protein by Zonal Centrifugation
Get PDF27 leaves.The problem. Isolation of Friend virus protein in an increased yield for immunological purposes by zonal centrifugation was the purpose of this experiment.
Procedure. Sucrose gradient zonal centrifugation was used to isolate Friend virus polysomes. The concentration of the polysomes and the removal of the sucrose was accomplished by ultrafiltration. Puromycin was used to release the nascent viral protein from the polysomes isolated, and the nascant protein was separated from the polysomes by centrifugation and then concentrated using ultrafiltration.
Findings. 1480 mg of protein was isolated from 30 Friend virus infected mice spleens. This amount was significantly more than the amount expected. Aggregates of soluble protein are believed to have sedimented along with polysomes and these proteins may contaminate the Friend virus protein isolated. Only partial release of the nascent protein was obtained in this study.
Conclusion. The use of sucrose as a separating medium does not separate large aggregates of soluble protein from the polysomes during zonal centrifugation. The use of puromycin in large amounts to release a usable quantity of nascent protein may make this method impractical due to high cost.
Recommendations. Cesium chloride should be used in place of sucrose in zonal centrifugation in an effort to separate the aggregates of soluble protein from the polysomes. An attempt to increase the release of nascent protein with puromycin should be made. The isolated protein should be innoculated into BALB/c mice to ascertain the effectiveness of the viral protein as an immunizing agent and the possible deleterious effect of the contaminating soluble protein
The Effects of Dimethyl Sulfoxide on the Mutagenic Action of Ethyl Methanesulfonate in Drosophila Melanogaster
Get PDF52 leaves.The problem. Ethyl methanesulfonate (EMS) is a potent alkylating agent, capable of inducing mutations in Drosophila at frequencies as great as 70%. EMS is often referred to as a radiomimetic substance because of the similarities between the clinical manifestations of radiation damage and injury due to alkylating agents. Dimethyl sulfoxide (DMSO) provides an effective protection against the mutagenic effects of radiation in many organisms including Drosophila. The major objective of this study was to determine the effects that topical application of DMSO would have on the mutagenic action of ingested EMS.
Procedure. Adult male Drosophila were treated in four ways. The five separate groups tested were treated with DMSO alone, EMS alone, DMSO followed by EMS, and EMS followed by DMSO. The fifth group was a control and received no treatment. Treated adult males were mated individually to three or four virgin Basc females. The Basc technique for detection of X-linked recessive lethal mutations was followed. Mutation frequencies were computed and subsequently submitted to chi square analysis.
Findings. The control group produced a mutation frequency of O.O%. This was used as a spontaneous X-linked recessive lethal mutation rate. The DMSO group demonstrated a 1.3% mutation rate. The EMS group produced a 35.9% mutation frequency. Pre-treatment with DMSO followed by EMS treatment resulted in a mutation rate of 31.6%. DMSO treatment following EMS treatment resulted in a 35.0% mutation frequency.
Conclusions. The data obtained from this study indicates that DMSO does not act as an antimutagenic substance against EMS in Drosophila. DMSO does appear to be slightly mutagenic after topical application and this application seems to reduce the overall reproductive capabilities of the treated males.
Recommendations. Further experimentation with various concentrations of DMSO and different methods of administration is necessary to fully elucidate the actual effects of DMSO in Drosophila
Spatial Distribution of Planktonic Copepoda and Cladocera in Red Rock Reservoir, Iowa, Summer, 1972
Get PDF34 leaves.The problem. The measurement of spatial distribution of Copepoda and Cladocera in Red Rock Reservoir, Iowa, summer, 1972, was undertaken. Water temperature, Secchi disk, and total water depth readings were also measured.
Procedure. Volumetric samples of free-swimming zooplankton were collected at weekly intervals from June 6 to September 8, 1972. Collections were made at three stations on each of four transects representing different areas of the reservoir. Samples were obtained from one meter intervals from the surface to three meters.
Findings. Sater temperature varied from a low of 18.5 C to a high of 30.0 C. Secchi disk readings ranged from 6 to 70 cm. Maximum readings were obtained near the dam and decreased towards the headwaters. Retention time varied from 3.9 to 55.6 days with a study mean of 10.7 days. A gradual increase in zooplankton numbers was noted from June 16 until a high was reached on July 5 (356 organisms per liter). The numbers then rapidly decreased until a low was reached on August 15 (0 organisms per liter). The dam transect always had the highest numbers of organisms with headwater transects having lower numbers of organisms. Eight species of zooplankton were identified during the study.
Conclusions. Highest zooplankton populations occurred near the dam with smaller numbers present up reservoir. Numbers of zooplankton per liter and retention times were lower than during a 1970 study. Retention time was the main controlling factor on zooplankton development. No correlations were found between zooplankton numbers and temperature, light penetration, and depth.
Recommendations. More station sites and more frequent sampling could enable the study of horizontal distribution of zooplankton. Monitoring reservoir inflow and outflow would enable the determination of population development within the reservoir. The interaction of zooplankton with phytoplankton and macrophytes should be investigated
An Evaluation by Recovered Alcoholics of Those Who Tried to Help
Get PDF33 leaves.The problem. It was the purpose of this study to ask recovered alcoholics for their opinions on what worked to help them achieve sobriety.
Procedure. After reviewing current literature, an opinionnaire wae prepared. The opinionnaire asked the respondents, recovered alcoholics, for a rating of the Help and Understanding they reoeived from the following six groups:
1-Physicians.
2-Spouse.
3-Clergy.
4-Psychiatrists and Psychologists.
5-Members of the court, attorneys, and legal officials.
6-Recovered Alcoholios.
The opinionnaire was validated by colleagues of the writer who work in the field of alcoholism treatment and by members of the Drake University faculty.
The opinionnaire was presented to the members of five Alcoholics Anonymous clubs in Iowa and to twenty residents of the North Central Alooholism Research Foundation in Fort Dodge,lowa. Copies and addressed envelopes were also left in the Carroll, Fort Dodge, and Webster City referral offices of the North Central Alcoholism Research Foundation.
Findings. On the basis of one hundred completed opinionnaires and the results thereof validated through F ratio tests and t-tests, it is the conclusion of this study, that of those who responded to the opinionnaire, they felt that the greatest source of Help and Understanding that they had received while drinking was from Recovered Alcoholics. The amount of Help and Understanding received from the group of Recovered Alcoholics was significantly greater than it was from each of the other five groups. In addition, no one of the other five groups was significantly more effective in Help or Understanding than any other groups out of this five
A Cytogenetic and Karyotypic Study of Eighty-Seven Patients Clinically Diagnosed as Having Down's Syndrome at Woodward State Hospital
No full text38 leaves.The problem. Eighty-seven patients clinically diagnosed as having Down's syndrome were studied by chromosome analysis at Woodward State Hospital, Woodward, Iowa, during June and July of 1972.
Procedure. A cytogenetic analysis was made on chromosomes prepared from leucocytes cultured from peripheral blood. Ten cells were counted and karyotypes prepared for each patient.
Findings. Among the eighty-seven patients, 54 males and 33 females, 60 (69%) were trisomic, 26 (29.9%) showed possible mosaicism and 1 (1.15%) carried a translocation. Three of the residents, including the patient with a translocation, were one of a set of twins.
Conclusion. The frequency of Down's syndrome based on a Woodward population of 750 residents was 11.6%. This frequency is in agreement with a reported frequency of 11.2% individuals with Down's syndrome determined from a 1967 census of 23,211 people in institutions for the mentally retarded. The frequency of 60 trisomic Down syndrome patients (69%) was lower than the 93% figure found by most investigators. The observed frequency (1.15%) of translocation Down's syndrome is lower than reported frequencies of 3 to 4% for other institutions. A frequency of mosaic Down's syndrome in the Woodward population of 29.9% is considerably higher than the 1 to 2% reported elsewhere for similar populations. The observed cases of presumptive mosaicism may include cases of regular trisomy which wiil be resolved by more extensive cytogenetic analysis.
Recommendations. A follow-up study to more completely characterize the mosaic Down's syndrome population is warranted to resolve the large observed deviation
Indentification of Abnormal Y Chromosomes in the Resident Population of Woodward State Hospital and School
No full text33 leaves.The problem. The screening of 507 residents of Woodward State Hospital-School for possible Y chromosome anomalies using a quinacrine mustard staining technique. This stain causes a bright fluorescence in the distal region of the long arms of the Y chromosome, making it possible to identify the Y chromosome. Procedure. The resident population was sampled using a finger puncture and blood smear technique to obtain the lymphocyte cells. The cells were stained using quinacrine mustard and the cells were screened using a Zeiss Photomicroscope II equipped with fluorescent illumination equipment. Fifty lymphocytes per individual were investigated noting single Y chromosomes, duplex Y chromosomes and double Y chromosomes.
Findings. The resident population divided into 212 females and 295 males. The women showed no Y chromosome anomalies. In the male population, 290 were observed to have only Y chromosomes. In this group of 290, 11 individuals showed a very low Y chromosome count. Five of the males were noted as possible XYY individuals.
Conclusions. The female population, as might be expected, exhibited no Y anomalies and 279 of the 290 males were diagnosed as having only one Y chromosome. The other group of 11 males with low positive Y investigations and 5 possible XYY males that were identified in this study are now the objects of further research involving karyotype analysis.
Recommendations. The sampling process and staining technique proved to be successful for screening a large population. I would also suggest that before any decisions are made from a screening process such as this, that a karyotype analysis be completed
The Effects of Conditions of Homogenization on the Contents of Nuclei Isolated From Rat Liver
Get PDF34 leaves.The problem. To determine the effects of degree of homogenization, on DNA, RNA, and protein content of nuclei isolated from rat liver. The procedure. Rat liver cells were broken with a Dounce homogenizer using variable numbers of strokes from 05 to 40. Nuclei were isolated, counted, measured and analyzed for nucleic acid and protein contents. Finding. It was found that the amount of homogenization had a very little effect on the contents of the isolated nuclei. Conclusion. Further homogenization has no effect on protein content of isolated nuclei. All of the protein must be leached out of the nuclei immediately. Nucleic acid content does not decrease as nuclear counts decrease thus fragmented nuclei are sedimented during the isolation process. Recommendations. The conditions of rehomogenization could be varied to determine the effects on protein and nucleic acid content. It is also recommended the forces of sedimentation be varied to further study the fragmented of invisible nuclei
Analysis of the Benthic Macroinvertebrate Community Structure for Assessment of Water Quality of the Des Moines River
Get PDF49 leaves.The problem. An evaluation of the water quality of the Des Moines River in the Des Moines, Iowa area was accomplished by sampling and analyzing the benthic macroinvertebrate community.
Procedure. Artificial substrates at five stations collected macroinvertebrates. Community structure was analyzed using species diversity indices. Species diversity
(D) and redundancy (R) values were used to calculate standardized distance (S.D.) values. These indices were analyzed using standard statistical tests of significance.
Findings. An analysis of variance for standardized distance (S.D.) values demonstrated significant difference for sampling dates and location of stations. When adjusted for current velocity, no significant difference was detected for station locations, but significance over time was retained. Mean value for species diversity was 2.19. Macroinvertebrate samples demonstrated seasonal distribution.
Conclusions. Current velocity appeared to be a major factor controlling colonization of macroinvertebrates in this study. The mean species diversity value indicated the Des Moines River is mildly polluted. Standardized distance (S.D.) values appear to be more meaningful than species diversity (D) alone in assessing community structure.
Recommendations. The main recommendation for future study is to compare benthos sampled with artificial substrates in different current velocities at the same location
Life Space Interviewing with Ten Female Juvenile Delinquents : An Attempt to Identify Common Perceptions
No full textv, 132 leaves. Advisor: Stuart C. TiedemanThe problem. The problem was to identify perceptions that were common to ten female juvenile delinquents at the Iowa State Training School for Girls at Mitchellville, Iowa. These perceptions would center around each girl's feeling about her present situation or life space, her perceptions of the events leading to her admittance to the Training School, and her perceptions of her future plans.
Procedure. The investigator asked for volunteers to help her with a project. After ten volunteers were selected, case histories were written for each. The volunteers were then interviewed, using the life space interviewing techynique. Selected parts of the taped interviews were transcribed. A three-column chart was made, listing information obtained from the interview, information obained from the case history, and the investigator's observations. The ten charts were studied, and conclusions were drawn concerning common perceptions.
Findings. The investigator found that the volunteers had an unsatisfactory relationship with their fathers. They criticized their mothers less than they did their fathers. The volunteers saw school as being worthless. They did not see themselves as being smart of able to compete for grades. The police were perceived as being cruel and unfair. The volunteers as a whole did not have concrete plans for their future, or felt that they would be successful. Several felt they had been talked into committing delinquent acts by other people