Pathogenic and serologic studies of Japanese quail infected with JM strain of Marek's disease herpesvirus.

Japanese quail were inoculated with Marek's disease herpesvirus at 1 day of age, and a second group of the same age was infected by contact with inoculated quail. A third group raised in our laboratory as a source of hatching eggs was accidentally infected with Marek's disease (MD). All quail were observed and examined for periods up to 360 days; the usual clinical signs of MD were not observed. However, the birds were susceptible to MD infection because of the evidence that: 1) The MD-specific agar gel-preceipitation (AGP) antigen was found in the feather tips or feather follicular epithelium of some of them; 2) the MD-specific AGP antibody was found in 6 of 57 exposed to MD; and 3) the virus was recovered from 4 MD-exposed birds by subpassage of their kidney cultures into quail embryo fibroblasts. The specificity of the AGP antigen or antibody in MD-infected quail was examined by the line of identity and cross-absorption tests. The antigen specificity was tested against similar to 700 sera from chickens and quail. Although most of these sera reacted with quail-positive antigen (QPA) prepared from MD-infected quail, some sera from infected or uninfected normal chickens reacted nonspecifically with QPA and with an antigen prepared from normal quail. By gel filtration on Sephadex G-150, the specific antigenic component could be separated from the nonspecific component(s) in QPA.

The effects of orientation on volume measurements of human left ventricular casts.

Biplane angiocardiography has emerged as a standard method for calculating left ventricular volume measurements. Validation of such measurements has separately been made for several projections of silicone casts of the left ventricle. This study was undertaken to establish and compare the regression lines for left ventricular cast volume measurements in the commonly used angiographic projections. Once established, any ventricular volume can be calculated from the slope and intercept of the regression line obtained from the appropriate angiographic projection.

Continuity of ambulatory care in an obstetrics and gynecology residency program.

Continuity of ambulatory care was instituted four years ago in a large residency training program serving private and clinic patients. Details of the program are described. Seventy-nine percent and 87% continuity of care was achieved for prenatal patients and women with gynecologic problems, respectively. Long-term continuity of care for preventive health maintenance was not attained. House officers and nurses believe that continuity of care fosters more efficient use of laboratory testing and physician time and results in better patient care.

Congenital atresia of the lower vagina with regular menses through a fistula: a therapeutic approach.

Presented is an unusual case of congenital atresia of the lower vagina with regular menses through a fistulous tract. Diagnostic ultrasound was very helpful in defining the problem and aiding in the determination of a therapeutic plan. Distention of the blind vaginal pouch with fluid greatly facilitated a surgical solution to the problem and has applicability to other forms of vaginal atresia.

Nucleic acid metabolism of placenta and fetus.

The preceding résumé of placental nucleic acid metabolism indicates considerable changes in RNA and DNA during the course of pregnancy in both human and animal experiments. The presence of an active protein-synthesizing apparatus closely allied with DNA and RNA metabolism has been observed in placental preparations; future studies should reveal even more direct relationships. The specific regulatory role of nucleic acids in normal and abnormal placental function is still unknown. In truth, such specific regulatory or control mechanisms are generally unproved among the entire mammalian (eukaryotype) system. Progress in learning about placental function and control may require more detailed information regarding RNA metabolism from molecular biology. The regulatory control of fetal or intrauterine growth as it relates to nucleic acids remains even more obscure. One of the major drawbacks in this study has been our inability to label fetal tissues adequately during the major portion of the pregnancy. The problem is made even more complex by the many factors involved in intrauterine growth, such as blood volume, uterine blood supply, oxygen flow and transfer, hormonal effects, and nutritional status, in addition to nucleic acids.

The role of gender in an obstetrics and gynecology residency program.

A brief historical review of the role of female medical students and female physicians in American medicine is presented. The 1985-1986 Council on Resident Education in Obstetrics and Gynecology Residency Data Bank was analyzed for gender distribution. Questionnaire studies were undertaken to study the possible effect of the increasing number of female residents in an obstetrics and gynecology residency program. Queries were sent to current and former residents, the attending staff, and the nursing and anesthesiology staffs. In order to evaluate the national scene, letters were mailed to directors of programs with 20 or more residents. The overall results indicated female residents have a positive effect on residency training.

A rat model for the study of intrauterine growth retardation.

An intrauterine growth retardation model was surgically created in pregnant rats by partial occlusion of the uterine artery in midhorn. The surgery was performed on the seventeenth day of pregnancy, and the animals were killed and studied on the twenty-first day of pregnancy. Statistical analyses demonstrated significant decreases in total weights of the fetuses in the upper horn compared with fetal weights of the lower horn. The greatest reduction in fetal weights occurred in the smaller horns with a fewer number of fetuses.

Forces retaining a contact lens on the eye between blinks.

The forces retaining a contact lens on the eye between blinks are analyzed using quasi-static equilibrium equations. The main forces are: (1) the surface tension forces around the contact lens periphery pulling the lens toward the cornea, (2) the reaction pressure force underneath the lens countering the effects of the surface tension, and (3) the weight of the lens. The reaction pressure force on the posterior side of the contact lens arises as a consequence of lubrication phenomenon. The centered lens can never be in static equilibrium. However, since the time period associated with the inertia effect in a thin-film system is much longer than the time between consecutive blinks, a quasi-static analysis is applied.

Comparison of endogenous and exogenous RNA primers of poly(U) polymerase in rat hepatic ribosomes.

The present work indicates that RNA primer requirements for poly(U) polymerase in the free ribosomes of the rat liver depend upon the degree of enzyme purification. The poly(U) polymerase activity obtained from a crude free ribosomal preparation was compared with the enzymic activity of a partially purified enzyme. After preliminary purification, the enzyme was fractionated by chromatography on Sephadex G-150 and CM-cellulose. Our results demonstrate the presence of several forms of poly(U) polymerase activities, some requiring exogenous RNA and others possessing their own endogenous primer RNA.

Protein synthesis in rat maternal and fetal tissues with starvation.

The incorporation a of 3H-leucine was studied in male rats and female rats 14 and 19 days pregnant that were either fed or starved for 48 hours. 3H-leucine incorporation into the liver was similar among all the fed animals. There was a 40% to 50% increase in the 3H-leucine incorporation of the placenta and fetus per milligram of ribonucleic acid from the fourteenth to the nineteenth day of pregnancy. With starvation there was a significant increase in 3H-leucine incorporation in both the fetus and the placenta of the 19-day-pregnant animal associated with a significant decrease in liver incorporation. Yolk sac placenta demonstrated a greater increase than the allantoic placenta. Both the male and 14-day-pregnant animals had minimal changes with starvation. The problems inherent in studying protein synthesis, especially during pregnancy, are presented.

Incorporation of labeled ribonucleic acid precursors into maternal and fetal rat tissues during pregnancy.

Tritium-labeled ribonucleic acid precursors, including cytidine, uridine, and orotic acid, were injected into rats with dated pregnancies (14 to 21 days) and virgin rats. The acid-insoluble counts indicating incorporation into fetal and placental tissues showed that the highest incorporation occurred with cytidine, particularly earlier in pregnancy. In contrast, uridine demonstrated a minor degree of incorporation but displayed facile and enhanced transplacental passage with duration of pregnancy as represented by acid-soluble counts. Orotic acid was minimally used by both fetal and placental tissues. The incorporation of labeled precursors into maternal liver, heart, and kidney demonstrated varying responses during the course of pregnancy.

Legal and social issues in medical genetics.

This paper was written for the purpose of providing the physician with a perspective of the conflicting scientific, individual, and societal interests which have been evoked by increasing medical and scientific innovation in the area of human genetic disease. In it the following subjects are considered: (1) obtaining genetic information by amniocentesis, by genetic counseling, and by screening; (2) disclosure of genetic data to the patient; (3) inclusion of genetic data on the medical record; (4) courses of action available to the individual after disclosure of genetic information, i.e., abortion, sterilization, etc.; (5) the state and involuntary sterilization; and (6) prohibitions on marriage.

Management of the Menopause.

Menopause is merely a clinically discernible clue symbolic of the multitude of changes preceding or following the cessation of menses by many years. Because of the time span involved, separating changes observed in the menopausal transition from other age-related maturational events presents serious methodologic problems. Of the host of psychologic and psychosomatic symptoms, only hot flushes and associated sweats occur more frequently in this epoch, while an interplay between hormonal and age-related maturational events presents serious methodologic problems. Of the host of psychologic and psychosomatic symptoms, only hot flushes and associated sweats occur more frequently in this epoch, while an interplay between hormonal and age-related effects is assumed in atrophic changes involving the genitourinary organs. The relation between menopause and osteoporosis is suggestive but by no means proven, as is the risk for cardiovascular disease. Empiric evidence points to the usefullness of estrogen for the management of vasomotor instability, the symptoms associated with atrophy of the genitourinary tract, and in the prophylaxis of osteoporosis, but not in the treatment of anxiety, depression, and other psychiatric disorders.

Changes in the free and membrane-bound ribosomes in maternal rat liver during starvation.

Free and membrane-bound ribosomal ribonucleic acid (RNA) from maternal rat liver was measured in virgin rats and in variously dated pregnant animals that were either fed or starved for one to four days. The total amounts of free and membrane-bound ribosomal RNA differed between pregnant and nonpregnant rats, but the free ribosomal RNA progressively decreased only in the nonpregnant animals. A similar conservation of membrane-bound ribosomal RNA was observed with starvation among the pregnant rats except for the very early dated pregnant rats. Radioisotope labeling experiments using 3H-labeled orotic acid demonstrated a slower increase in specific activity among fed rats, irrespective of pregnancy state. However, metabolic and physiologic changes associated with pregnancy imposed additional complicating factors to the study.

Relation between common antigen and membrane antigens associated with Marek's disease herpesvirus and turkey herpesvirus infections.

The appearance of two kinds of membrane antigen (MA) in Marek's disease herpesvirus (MDHV) or herpesvirus of turkey (HVT) infected cells was examined using antiserum to the common antigen (common-Ag). No early-appearing MA(EMA) was detected in these cultures until 16 hours post-inoculation, after which a number of cells in these cultures had late-appearing membrane antigen (LMA) as detected by immunofluorescence (IF). Fluids from cultures infected with these viruses were examined for the presence of the common-Ag by agar-gel precipitation (AGP) test. No common-Ag was detected until 16 hours, but after 24 hours, it was detected by AGP test. These results suggest that the common-Ag is related to LMA but not to EMA.