Showing papers by "Saint Francis University published in 1977"

Effect of somatomedin and growth hormone on bone collagen synthesis in vitro.

Abstract: Although pituitary hormones, particularly growth hormone (GH), are known to influence skeletal growth, there is no evidence for a direct effect of GH or GH-dependent factors (somatomedins) on bone as opposed to cartilage. We have examined the effects of GH, a somatomedin (Sm) preparation, and serum from intact and hypophysectomized rats on bone collagen synthesis in cultures of 21-day fetal rat calvaria. Collagen synthesis and non-collagen protein synthesis were measured by the incorporation of 3H-proline into collagenase-digestible (CDP) and noncollagen protein (NCP). Bovine and rat GH caused a small inhibition in the incorporation of labeled proline into CDP which was not dose related. Sm in doses of 18–540 mU/ml increased the incorporation of proline into CDP up to three-fold after 24 hr in culture. Sm also had a smaller and more variable stimulatory effect on the labeling of NCP. The effects of Sm were maximal after 3 hr of treatment and were maintained for 96 hr. Sm (60 mU/ml) and insulin (10−8 M) had effects of similar magnitude and were not additive. The addition of 10% serum from hypophysectomized rats stimulated the labeling of both CDP and NCP, but serum from rats with intact pituitaries had a greater effect. Treatment of hypophysectomized rats with thyroxine, corticosterone, and GH. did not increase the bone collagen synthesis stimulating activity of the serum, although GH treatment did increase serum Sm activity by a pig cartilage assay. The results indicate that GH dose not stimulate bone collagen synthesis directly. However, they suggest that the pituitary gland either releases or stimulates the production of factors which stimulate bone collagen synthesis. Sm may be such a factor, but sulfation activity and bone collagen synthesis stimulating activity may be dissociable.

Pseudobacteremia: falsepositive blood cultures from mist tent contamination

Abstract: In the seven-month period from July 1975 through January 1976, 11 pediatric patients had Acinetobacter calcoaceticus var. anitratus cultured from blood; this organism had not been isolated from pediatric patients in the previous six months. In 10 of 11 patients, only the first of two cultures was positive. All patients recovered uneventfully, although only two were treated with appropriate antibiotics. Nine of 11 had been in mist tents at the time of the culture. Mist cultured from one tent contained the same organism found in the patient's blood culture. Eight of 10 patients, however, had blood for culture drawn from the same needle as samples for other blood work, compared with only three of 13 controls (p = .013); this represented a deviation from proper blood culture technique, and a mock trial confirmed contamination of blood cultures when technique was broken. Contamination by this organism occurred in the tent water reservoir and mist, and the nose and skin of the children were colonized. The hands of respiratory therapy technicians and blood-drawing personnel became contaminated while handling the mist tents. Thorough attention to hand-washing, tent sterilization, and technique in drawing blood cultures stopped the pseudo-epidemic.

Juvenile nasopharyngeal angiofibroma. An unusual presentation as an oral mass.

Abstract: • Although juvenile nasopharyngeal angiofibroma (JNAF) usually presents as a mass in the nasopharynx, the primary manifestation may, in rare instances, occur intraorally. We observed such a case in a 12-year-old boy. The clinical finding of hemorrhage from the nasopharynx or contiguous areas in a male adolescent is an important diagnostic clue which should alert the clinician to the possibility of JNAF as the underlying cause.

A versatile electron collimation system to be used with electron cones supplied with Varian's Clinac 18.

Abstract: A method of fabricating individualized electron shields with openings corresponding to desired field shapes and sizes is discussed. The electron shields are made from an alloy called Lipowitz' metal. These shields are designed to be mounted on any of six cone sizes provided with the Varian's Clinac 18 linear accelerator. The effect of these shields on electron dosimetry is shown.

Effect of inline filtration of intravenous infusions on the incidence of thrombophlebitis

Abstract: The effect of inline filtration on the incidence of infusion phlebitis was examined in a community hospital. Two general surgical units, comparable in their patient populations, were studied during a one-month period. On one unit, an extension set with a 45 micrometer filter was attached to every i.v. catheter; no inline filtration was instituted on the second unit. The use or nonuse of a filter was not blinded. The filter was replaced every 24 hours or sooner if blockage occurred. A total of 49 patients (107 i.v.s) were studied in the group with filters and 40 patients (84 i.v.s) without filters. Phlebitis was graded on a scale of 0 to 4. The proportion of patients with phlebitis in the filter group was 86%; in the no-filter group, 75%. In the filter group, 67% of the catheterizations ended in phlebitis; in the no-filter group, 63%. Upon first catheterization, phlebitis developed in 63% of the filter group and 58% of the no-filter group. None of these differences was significant (p = 0.05). There was also no significant difference between the two groups in the severity of phlebitis and the incidence of phlebitis following the administration of irritating solutions containing cephalothin sodium or potassium chloride. Based on this study, the value of inline filtration in routine clinical conditions appears to be questionable.

Radiation Dose to Hands from Radiopharmaceuticals—Preparation Versus Injections

Abstract: Since there has not been a great deal in the literature on personnel radiation exposure, particularly to the hands, we investigated the question of which phase of radionuclide handling causes the greatest radiation dose to the hands: preparation or injection. Results indicate that the major radiation dose occurs during preparation. The total dose, however, is well below the maximum permissible dose set by the National Council on Radiation Protection. Lead foil wrapped around the syringe cuts the dose to the hands somewhat, but the overall exposure to the hands while injecting is quite small.

Precision cardiotachometer calibrator.

Abstract: MANY types of physiological applications require measurement of heartrate. Most of these are intended for clinical monitoring where accuracies are limited to 45 %. However, there are other instances, such as monitoring the rate of cardiac pacemakers, where a higher precision is needed. To calibrate or test ratemeters of high accuracy, a pulse generator must be employed whose error is at least one order of magnitude less than that of the ratemeter. The need to check calibration is particularly important for cardiotachometers that use reciprocation techniques based on the hyperbolic relation between R-R interval and the heartrate. Unfortunately, most commercially available pulse generators do not provide calibrated accurate pulse rates at the frequencies of interest. One device (JAMES et al., 1969) utilises the US 60 Hz mains frequency and a number of integrated circuits to provide calibrated pulse rates from 360 to 25 beats per minute (b.p.m.). Even though the mains frequency can be considered as a secondary frequency standard with an