Correlation of serum, tumor, and liver serum glycoprotein: N-acetylneuraminic acid transferase activity with growth of the R3230AC mammary tumor in rats and relationship of the serum activity to tumor burden

The observation that the activity of sialyltransferase (EC 2.4.99.1; serum glycoprotein:N-acetylneuraminic acid transferase) is often elevated in the serum of cancer patients necessitates an elucidation of the interrelationships of this serum enzyme with host tissues. Accordingly, the activity of this enzyme in serum, tumor, and liver was determined at various times after implantation of the R3230AC mammary carcinoma into Fischer rats. Results from samples obtained at numerous, sequential time points demonstrated that significant elevations in serum sialyltransferase enzyme activity occurred only in animals bearing large tumor burdens, i.e., greater than 20 g, or in animals with tumors present for longer than 21 days. In these tumor-bearing rats, the activity of sialyltransferase increased in liver tissue at 21 to 25 days concurrently with the increase in serum enzyme activity, suggesting that the liver may be a potential source of the serum enzyme. Sialyltransferase activity in tumor tissue was quite variable; the activity increased one week after tumor implantation and remained at the same level thereafter. When tumors were excised, the activity of the serum enzyme returned to control values within four days after surgery, suggesting that the half-life of serum sialyltransferase was two days. Serum enzyme levels were again elevated upon regrowth of the tumor. These results show that the serum sialyltransferase alters its activity in conjunction with changes in tumor burden.

Developments in a rehabilitation service for psychiatric patients

This paper deals with the operation of the Rehabilitation Services of the Clarke Institute of Psychiatry in Toronto, Ontario. It is particularly addressed to developments in the service during the last two and one-half years. Included are: a brief historical review; a description of current goals and procedures; plans for the future; a description of the work adjustment program--a new adjunct to the service; some demographic information on clients served in 1977 and 1978; and a discussion of the computerized data collection, outcome studies, program analyses etc. now underway. The tasks of the members of the rehabilitation team will be outlined. Emphasis is placed on the work of occupational therapists who have played a major role in planning, establishing and conducting the service. Flow charts of service procedures are included.

Patterns of skin injury in nonaccidental and accidental injury

The patterns of soft tissue injuries in a group of 154 children reported to protective services for child abuse or neglect were compared with patterns of soft tissue injury found in a group of 91 emergency room patients who sustained an accidental injury and 105 children seen in a pediatric ambulatory clinic. All children in the three groups were 1 to 12 years old. Children in the suspected child abuse and neglect group had significantly more (P less than .01) soft tissue injuries over the cheeks, trunk, genitals, and upper legs. Lacerations were significantly more common (P less than .001) in the emergency room group.

The turnover catabolism and excretion of folate administered at physiological concentrations in the rat

This study examines the distribution of folate-derived compounds in rat urine on a daily basis after the administration of tracer doses of radioactive [3H]pteroylglutamic acid. The identification of 10-formyldihydropteroyl-glutamate in the rat urine, prior to equilibration of the tracer, is also reported for the first time.

The identification of the products of folate catabolism in the rat

Further analysis of rat urine containing labelled catabolites derived from administered 3H- or 14C-labelled folic acid is described. The results support previously described studies, and show that folate catabolism in the rat takes place by cleavage of the C9-N10 bond, and not by excretion of inactive forms of the vitamin which still contain the intact folate skeleton.

Clinical and immunological study of percutaneous revaccination in children who originally received smallpox vaccine subcutaneously

In a large multicenter smallpox vaccination study carried out from 1970 to 1973, it was found that 39% of children who were initially immunized by the subcutaneous route and then challenged percutaneously with a standard vaccination did not have measurable neutralizing antibody upon follow-up. Because of this finding, a percutaneous revaccination study was conducted at the St. Louis study center in 1975 and 1976. There were four study groups, which were composed on the basis of route of primary immunization (subcutaneous or percutaneous) and whether neutralizing antibody was detectable following the original percutaneous challenge immunization. Of 52 children revaccinated, all but four had accelerated reactions. There was no difference in size of lesions or day of maximum erythema among the four study groups. Only 66% of children originally vaccinated subcutaneously who did not have postchallenge neutralizing antibody had measurable neutralizing antibody following revaccination. Transformation studies with vaccinia viral antigen before and after revaccination were performed on lymphocytes from 50 children. There was no appreciable differences in responses either before or after revaccination when the four groups were compared. However, the mean stimulation ratio for the total group increased from 2.4 before revaccination to 4.6 3 weeks later. In primary subcutaneous vaccine recipients without pre-revaccination neutralizing antibody, lymphocyte transformation correlated directly with the neutralizing antibody response.

Somatostatin inhibition of glucose-induced electrical activity in cultured rat islet cells

Electrophysiological studies of rat islet cells in monolayer culture were undertaken to determine the role of transmembranous ionic fluxes in the inhibitory action of somatostatin on insulin release. In the presence of somatotropin release inhibiting factor (SRIF) (2.5 nM), hyperpolarization occured with or without glucose (16.6 mM) in the medium. SRIF also inhibited the incidence of glucose-induced spike activity. The inhibitory action of SRIF occurred within 5 min and was readily reversible. An increase in extracellular K+ (5-13 mM) or Ca2+ (2.3-4.6 mM) prevented SRIF inhibition of glucose-induced electrical activity. The secretory response of cultured islets to glucose (16.6 mM) was completely inhibited by SRIF (2.5 nM). The presence of high [Ca2+]o or [k+]o enhanced insulin release in the presence of SRIF and glucose. Although phentolamine (5.0 microgram/ml) did not block the inhibition of glucose-induced electrical responses by SRIF, it prevented the inhibitory action of epinephrine (0.2 microgram/ml). It is concluded that the primary action of SRIF is to alter transmembranous cationic fluxes, as manifested by hyperpolarization and a decrease in the incidence of spike activity, which may prevent glucose from eliciting a normal secretory response.

Exchange of phospholipids between mitochondria and microsomes in vitro stimulated by yeast cell cytosol

Yeast cell cytosol stimulated the exchange of phospholipids between yeast mitochondria and microsomes in vitro, and also between organelles isolated from rat liver. The major phospholipids exchanged in both cases were phosphatidylinositol and phosphatidylcholine, together with smaller amounts of phosphatidylethanolamine. Evidence was also obtained that interconversion of phospholipids occurred during the incubation, probably via base exchange mechanisms.

Defective bud formation in human cells chronically infected with subacute sclerosing panencephalitis virus

Human prostate cells chronically infected with the Mantooth strain of subacute sclerosing panencephalitis (SSPE) virus multiply normally, fuse only occasionally to form giant cells, and yet have twisted intracytoplasmic nucleocapsids. These cells are able to support replication of vesicular stomatitis virus, although they release only small amounts of SSPE virus. To determine why carrier cells do not produce virus, they were examined with techniques for surface replication, freeze-fracturing, and immunoperoxidase labeling with SSPE antibody. The surface of carrier cells, like that of productive cells, is characterized by ridges crowned with viral antigens and devoid of the intramembrane particles revealed by freeze-fracture techniques. Since surface ridges form where nucleocapsids attach to the membrane, the shape and length of ridges are indicative of the shape and length of the underlying nucleocapsid. Whereas ridges on productive cells are serpentine in shape, those on carrier cells are typically straight or hairpin shaped, and the hairpin ridges are twice as long as serpentine ridges on productive cells. Furthermore, the spacing between ridges on carrier cells is never as small as that in productive infections, so that continuous sheets of viral membrane are never formed. The majority of carrier cells lack the round viral buds observed in productive cells but have, instead, many elongated processes attached to the cell surface. Each of these processes contains one or two hairpin ridges overlying hairpin-shaped nucleocapsids. These "hairpin buds" are restricted to a single region of the carrier cell surface, whereas viral buds are distributed over the entire surface of productive cells. Thus, there are several structural defects in carrier cells that depend on the specific interaction of a certain viral strain with a certain cell type. These defects prevent the deployment of viral antigen in some regions of the cell surface, the formation of nucleocapsids of normal length, the coiling of attached nucleocapsids, and the consolidation of sheets of viral membrane into spherical buds with the nucleocapsids coiled inside. These defects may account for the failure of carrier cells to shed infectious virus.

The use of a single venous blood sample to assess oxygen binding in haemoglobin

The measurement of pH, PO2, PCO2 and SO2 in a single venous blood sample can be used to determine the P50 at standard or at in vivo conditions. This technique makes it feasible for a physician, firstly, to make an assessment of the net adaptation of the red cell to reductions in blood oxygen content or flow and, secondly, to make an initial assessment of whether a haemoglobin with altered affinity for oxygen is present in subjects with polycythaemia or anaemia.

Effect of isoleucine deprivation of rabbitpox virus DNA synthesis in mouse L cells

Synthesis of rabbitpox DNA was inhibited in mouse L cells deprived of isoleucine. Time-course patterns of incorporation of radiolabelled precursors into viral DNA revealed that synthesis of viral DNA began about 6 h after reversal of the isoleucine-deficient state.

Factitious changes in binding of oxygen to hemoglobin when based on extracellular pH in the presence of certain blood additives like radiographic contrast media

Construction of oxygen-hemoglobin DISSOCIATION CURVES BASED ON EXTRACELLULAR PH and using blood tonometered with 5 per cent CO2, is misleading under certain experimental conditions. These include the presence in blood of poorly penetrating non-ionic molecules like sucrose of poorly penetrating anionic aompounds like radiographic contrast materials. False conclusions regarding the position of the oxygen-hemoglobin dissociation curve can result because of the disturbance of the normal pH gradient between plasma and red cell induced by such chemicals.

The relationships between arterial oxygen flow rate, oxygen binding by hemoglobin, and oxygen utilization after myocardial infarction

The interrelationships of arterial oxygen flow rate index, oxygen binding by hemoglobin, and oxygen consumption have been examined in patients with acute myocardial infarction. Proportional extraction of oxygen increased in close association with decreasing oxygen flow rate, and hence, whole body oxygen consumption was constant over nearly a three-fold variation in arterial oxygen flow rate. A reduction in hemoglobin-oxygen affinity at in vivo conditions of pH. Pco(2) and temperature also occurred in proportion to the reduction in arterial oxygen flow rate. Therefore, the increased proportional removal of oxygen from arterial blood at low oxygen flow rates, required to maintain oxygen consumption, may have been facilitated by the reduced affinity of hemoglobin for oxygen at in vivo conditions. However, the decrease in affinity did not appear to explain more than 30-40% of the increased extraction. Respiratory alkalosis was a frequent occurrence in these patients and 2,3-diphosphoglycerate was positively associated with blood pH as well as with the time-averaged proportion of deoxyhemoglobin in arterial and venous blood.Hemoglobin-oxygen affinity measured at standard conditions and the mixed venous oxygen saturation were equally good indicators of reduced arterial oxygen flow rate in patients without shock. However, Svo(2) is more easily measured and is a more useful indicator of reduced oxygen flow rate, since its relationship to oxygen flow appears to be independent of affinity changes and time.

The effects of cyproterone acetate on the spontaneous activity and seminal vesicle weight of male rats

The wheel-running activity of 19 male rats was examined before and after castration. Castration significantly reduced spontaneous activity. Testosterone propionate (TP) administration increased activity to levels before castration. Cyproterone acetate given with TP did not inhibit the increase in activity but inhibited the growth of seminal vesicles.

Factors associated with participation, attrition, and outcome in a smoking cessation program at the workplace

Despite their growing popularity, worksite health-promotion programs have generally been characterized as having low participation rates, high attrition rates, and modest outcomes. This investigation identified the predictors of participation, attrition, and outcome of worksite smoking-cessation program. Subjects were regular cigarette smokers recruited from two worksites. Of 66 eligible smokers in the two worksites, 44 (67%) agreed to participate in the program. Fifty-five percent (24 of 44) of these completed the program. Of those completing the program, 29% had quit smoking by posttest and 17% were abstinent at the 6-month follow-up. Results indicated that a different set of variables predicted participation, attrition, and outcome. The significant predictors of smokers who participated were the length of cessation in previous abstinence attempts, the number of years they smoked, and the belief regarding personal vulnerability in contracting a smoking-related disease. Levels of pretest carbon monoxide along with attitudes regarding the adoption of smoking restrictions in the worksite predicted attrition. Posttest cessation was related to nicotine levels of cigarette brand smoked at pretest and pretest beliefs regarding postcessation weight gain. Abstinence at the 6-month follow-up was predicted by the number of co-workers who smoked and pretest concerns related to postcessation weight gain. The results are discussed in terms of future evaluation and intervention efforts.

Knowledge and beliefs regarding the consequences of cigarette smoking and their relationships to smoking status in a biracial sample

The purpose of this investigation was to evaluate carefully smoking-related knowledge and beliefs and their relationships to smoking status in a large, heterogeneous sample of smokers and nonsmokers in two settings: (a) a large, biracial southern city and (b) a small midwestern community. Participants were 611 (198 male, 413 female) adult respondents to a random-dialing telephone survey in Fargo, North Dakota (n = 200), and Memphis, Tennessee (n = 411). Each participant was given the Smoking Attitudes Survey, which assesses generalized health beliefs as well as health-related problems associated with smoking. Participants' knowledge of smoking-associated diseases (e.g., lung cancer) and of diseases not associated with smoking (e.g., kidney stones) was assessed. Stepwise regression analysis of composite knowledge scores revealed four independent predictors of the health consequences of smoking: education, race, smoking status, and income. Smokers, compared to nonsmokers, reported less knowledge related to the health consequences of smoking, were more likely to be male, were less concerned with the health consequences of smoking, and were more concerned about the health consequences of cholesterol. The best predictor of smokers who had never attempted cessation was their greater concern over weight control when compared to smokers with a history of smoking cessation attempts. The results are discussed in terms of smoking prevention and intervention efforts.