P53 loss of heterozygosity (LOH) in formalin-fixed paraffin-embedded leiomyosarcoma (LMS): a novel report

BACKGROUND

The occurrence of p53 loss of heterozygosity (LOH) is a common genetic event in malignancy. LOH occurs when a heterozygous locus loses one of its two parental alleles, becoming homozygous at that locus, by either copy number loss (CNL-LOH) or by becoming copy number neutral (CNN-LOH). A role for CNL-LOH (cnLOH) has been postulated in cancer aetiology. Loss of heterozygosity (LOH) results in irreversible genetic loss.

AIMS

LOH was determined in DNA extracted from formalin-fixed paraffin-embedded (FFPE) leiomyosarcoma (LMS) specimens in a retrospective study from 30 patients, to assess the prognostic significance of LOH. The findings were analysed and their validity assessed. LOH was an adverse prognostic factor in LMS. Prospective uniform standardisation of formalin-fixation techniques is required.

METHODS

DNA was extracted from 169 formalin-fixed paraffin blocks of 30 patients with LMS, following extensive tissue microdissection. Genomic DNA was amplified using the polymerase chain reaction (PCR) technique. Fluorescence-based microsatellite PCR was used to detect and quantitate heterozygosity loss.

RESULTS

LOH was detected at gene locus 17p13 in 16 LMS (Four grade 2 and 12 grade 3 LMS). LOH was not detected in 14 LMS cases (one grade 1, five grade 2 and eight grade 3 LMS). LOH was associated with shorter patient survival.

CONCLUSIONS

The results reported herein endorse the value of utilizing FFPE DNA in identifying LOH as a prognostic factor in LMS. The results have implications for tumour biobanking and precision medicine in patients with sarcomas.

Development of contemporary issues courses: pitfalls and opportunities

The development and teaching of contemporary issues courses provide unique opportunities for expanding influence, service to the university, and professional development. During the last decade, there has been a proliferation of such courses centered on the issue of human exploitation of animals. The Ohio State University's general education curriculum, initiated in 1990, includes a requirement that senior students complete a 5-credit course in the category Issues of the contemporary world. Currently, 28 courses are offered in this category, and 5 are from the College of Food, Agricultural, and Environmental Sciences. Our course, entitled Issues concerning the use of animals by humans, was the first from the college included in this category. The course has been offered continuously since 1990-4 quarters per year since 1992. Challenges included gaining approval of the course through a special oversight committee, enhancing visibility of the course outside the college, instructor education, and control of personal biases. The development of this type of course is, necessarily, a continuous process. Instruction of this course has been challenging, enlightening, and exceedingly rewarding. Instructors of similar courses at 11 other universities reported experiences similar to ours.

Isolation and characterization of Salmonella from broiler carcasses or parts

A study was conducted to determine and characterize Salmonella contamination on ready-to-cook broilers or parts in the Columbus, OH, metropolitan area. Ten to twelve samples per store were examined, using a whole-carcass rinse method. The Salmonella cultures isolated were tested for resistance to a series of nine drugs and, subsequently, were sent to the National Veterinary Services Laboratory at Ames, IA for serotype identification. Cultures identified as Salmonella were also examined for the presence of plasmids. Salmonella was isolated from one or more samples obtained from 11 of the 12 stores, and from 43% of the 142 samples examined. The serotypes isolated most often were Salmonella hadar, Salmonella heidelberg, and Salmonella johannesburg. Of the 55 cultures tested for drug resistance, 32.7% were sensitive to all nine drugs. The most-common patterns of drug resistance were triple sulfa (41.8% of the cultures) and tetracycline (34.5% of the cultures). Plasmids were found in 41.7% of the 36 cultures analyzed. The results of the present study indicate that the probability is high that carcasses from retail stores will have at least a few drug-resistant Salmonella cells.

Effects of kanamycin administration to poultry on the interspecies transmission of drug-resistant Salmonella

Three experiments were conducted to assess the relationship between antibiotic administration to poultry and the transmission of drug-resistant Salmonella through a simulated food chain. Poults were inoculated per os with either multiply drug-resistant Escherichia coli and drug-sensitive S. typhimurium or with multiply drug-resistant S. typhimurium. One-half of the poults inoculated with drug-sensitive S. typhimurium and all poults given drug-resistant S. typhimurium received kanamycin in their drinking water. Liver tissue from these poults was incorporated into diets fed to rats, half of which were treated with kanamycin. Antibiotic administration to the poults was associated with a significantly (P less than .05) higher frequency of transmission of drug-resistant S. typhimurium to the rats through the simulated food chain. S. typhimurium was isolated only from rats treated with kanamycin. The highest frequency of isolation of drug-resistant S. typhimurium from rats (40%) was observed in kanamycin-treated rats fed a diet containing liver from kanamycin-treated poults. Results of this experiment indicate that antibiotic administration can increase the frequency of transmission of drug-resistant Salmonella through the food chain.

Effects of kanamycin administration to poultry on the proliferation of drug-resistant Salmonella

Four experiments were conducted to examine the relationship between antibiotic administration to poultry and the in vivo proliferation of Salmonellae. The frequency of isolation of drug-resistant transconjugant S. arizonae from the livers of chicks inoculated per os with multiply drug-resistant Escherichia coli and drug-sensitive S. arizonae was directly related to the concentration of kanamycin administered to the chicks in their drinking water. Kanamycin administration was also associated with a significant (P less than .05) increase in the frequency of isolation of drug-resistant transconjugant S. typhimurium from the intestines and livers of poults inoculated with drug-sensitive S. typhimurium and multiply drug-resistant E. coli. Kanamycin administration significantly reduced the spread of drug-sensitive S. typhimurium to the livers of poults inoculated only with that strain. These experiments demonstrate that antibiotic administration to poultry can enhance the proliferation of drug-resistant Salmonella.

In vivo transfer of antibiotic resistance to a strain of Salmonella arizonae

Two trials were conducted to determine the transferability of antibiotic resistance in vivo between two strains of enteric bacteria. Newly hatched turkey poults were inoculated per os with a strain of Escherichia coli resistant to kanamycin, tetracycline, and ampicillin, a strain of Salmonella arizonae resistant to nalidixic acid and streptomycin, or both strains. Kanamycin was added to the drinking water of some poults. To test for S. arizonae cells which had received transferable resistance determinants in vivo from the E. coli strain, samples were collected by swabbing the recta of the poults and by removing segments of the intestines and livers after the birds were sacrificed. Nalidixic acid was added to the isolation media to prevent in vitro transfer from occurring after the samples were collected. Salmonella arizonae resistant to nalidixic acid, streptomycin, kanamycin, tetracycline, and ampicillin were isolated from 20% of the rectal samples taken from poults that had received both bacterial strains. S. arizonae cells which had received resistance determinants in vivo were also isolated from 73% of the intestinal samples and 8% of the liver samples taken from birds inoculated with both donor E. coli and recipient S. arizonae. Salmonella arizonae demonstrating resistance to all five antibiotics were recovered from all intestinal samples taken from birds given kanamycin in their drinking water immediately after the last S. arizonae inoculation but from only 43% of such samples taken from birds given no kanamycin.

Incidence and in vitro acquisition of transferable drug resistance in Salmonella arizonae

Fifty-eight cultures of Salmonella arizonae isolated in 1983 from poultry sources and 21 cultures isolated in 1972 to 1974 were screened for resistance to nalidixic acid, chloramphenicol, triple sulfa, ampicillin, tetracycline, streptomycin, and kanamycin by the standardized disc susceptibility method. Sensitivity to all seven drugs was observed in 51% of the cultures tested (76% of the older cultures and 41% of the recent isolates). Resistance to two or more drugs was observed in 36% of the cultures tested (14% of the older cultures and 43% of the newer ones). The highest incidence of resistance was to streptomycin. Salmonella arizonae cultures sensitive to all seven drugs were tested for the ability conjugatively to acquire kanamycin, streptomycin, tetracycline, and ampicillin resistance determinants from a multiply resistant strain of Escherichia coli K12NA. Complete or intermediate resistance to all antibiotics was transferred to 93% of the sensitive cultures at 41 C and 85% at 28 C. Kanamycin resistance was transferred most frequently, and ampicillin resistance least frequently.

Fluorine Is a Major Constituent of the Marine Sponge Halichondria moorei

Fluorine constitutes about 10 percent of the dry weight of the marine sponge Halichondria moorei. The fluorine occurs as potassium fluorosilicate, which is a potent anti-inflammatory agent. A closely related sponge living in the same habitat does not contain any fluorine. The habitat was found to be free of fluorine except for the small amount naturally present in seawater.

Sex-linked dwarfism and response to two Newcastle disease vaccines

In a series of battery trials, normal-sized (AG) broiler type and sex-linked dwarf chicks (D2) were vaccinated with a double dose of Roakin or LaSota strain Newcastle Disease (ND) vaccine, or were challenged with the Gilbert-Boney ND virus. The AG chicks developed higher hemagglutination inhibition titers but suffered more mortality than the D2 chicks following administration of Roakin strain vaccine. Similar percentages of mortality occurred in AG x AG, AG x D2 and D2 x D2 male chicks challenged with the Gilbert-Boney ND virus. Results indicate that the dwarf strain and the AG x D2 cross strain chicks are no more susceptible to ND than the AG strain.

The clinical value of frequency analysis of the first heart sound in myocardial infarction

A sensitive technic for frequency analysis of the first heart sound (S 1 ) during isovolumic contraction time (ICT) was developed. Recorded heart sounds were filtered with a dynamic analyzer. Amplitudes of frequencies between 30 and 70 cps were plotted as a percentage of peak total energy of S 1 against frequency. A consistent and reproducible frequency "fingerprint" was obtained in 74 normal subjects. Frequencies of S 1 were shown to be directly proportional to ventricular elasticity (VE) and inversely proportional to combined ventricular mass (VM). VM is constant during ICT. Amplitude at 40 cps was less than at 30 cps because of reduced VE (myocardial infarction), increased VM (athletes), or combined reduction in VE and increased VM (myocardiopathy). Normal patterns were found in aortic insufficiency (increased VE and VM). Diagnostic patterns were found in 21 of 24 patients with acute myocardial infarction (MI) but were similar to patterns found in patients with healed infarcts and myocardiopathy and athletes. Acute pulmonary embolism could be differentiated from MI.

Changes in the differential leukocyte count of chicks inoculated with Salmonella

Studies were conducted to determine the effects of Salmonella anatum and S. heidelberg infections on the differential leukocyte counts of baby chickens. Newly hatched broiler-type chicks were inoculated in the yolk sac with suspensions of either S. anatum or S. heidelberg. At 0, 24, 48, and 72 hr after inoculation, blood was taken by heart puncture from chicks of both inoculated groups and from a group of uninoculated chicks. The averages of the leukocyte counts of three or four chicks from each group were used as the blood values for specific time intervals. The six classes of leukocytes counted were lymphocytes, monocytes, juveniles, heterophils, eosinophils, and basophils. The leukocytes classified as juveniles were immature or degenerate heterophils and were found almost exclusively in the infected chicks. Changes in heterophil, juvenile, and lymphocyte counts were affected by both the number of cells in the inoculum (300 versus 3 million cells of S. anatum) and species (S. anatum and S. heidelberg). Infection with either Salmonella species resulted in the development of a severe heterophilic leukopenia, and a significant increase in the percentage of both juveniles and lymphocytes by 48 hr postinoculation. Mortality rate was higher in groups of chicks inoculated with S. heidelberg than in groups given S. anatum.

Growth of salmonella in chickens' yolk sacs and its relationship to pathogenicity

Newly hatched chicks were inoculated in the yolk sacs with standardized suspensions of Salmonella anatum, S. heidelberg, or S. infantis. At intervals between 3 and 48 hr postinoculation, chicks from each group were sacrificed, the average number of viable cells per yolk sac was determined, and liver tissue from each chick was examined for Salmonella. Growth patterns of the three species were almost identical when each chick was inoculated with about 3.5 million cells, but S. heidelberg was recovered more frequently from the liver, and caused a much higher percentage of mortality than did either S. anatum or S. infantis. When 100-fold dilutions of the suspension of S. heidelberg were used, mortality and recovery rates of the bacterium from the liver were directly related to the number of cells injected. The logarithmic growth phase was lengthened as the number of cells in the inocula was decreased; consequently, there was little difference in the average number of S. heidelberg cells per yolk sac at 36 or 48 hr postinoculation regardless of number of cells injected. Results of these trials indicated that factors other than rate of multiplication in the yolk sac are responsible for observed differences between Salmonella species in degree of pathogenicity for baby chicks.