Showing papers by "Saint Francis University published in 1989"

Insulin-like growth factor I mediates selective anabolic effects of parathyroid hormone in bone cultures.

Abstract: PTH was studied for its effects on bone formation in cultured rat calvariae. 0.01-10 nM PTH stimulated [3H]thymidine incorporation into DNA by up to 4.8-fold. Although continuous treatment with PTH for 24-72 h inhibited [3H]proline incorporation into collagen, transient (24 h) treatment enhanced [3H]proline incorporation into collagen 24-48 h after the hormone was removed. The collagen stimulated by PTH was type I and the effect was observed in the periosteum-free bone and was not blocked by hydroxyurea. Furthermore, treatment with 1-100 nM PTH for 24 h increased insulin-like growth factor (IGF) I concentrations by two to fourfold, and an IGF I antibody prevented the PTH stimulation of collagen synthesis, but not its mitogenic effect. In conclusion, continuous treatment with PTH inhibits calvarial collagen, whereas transient treatment stimulates collagen synthesis, and the stimulatory effect is mediated by local production of IGF I.

Regulatory Effects of Insulin-Like Growth Factors I and II on Bone Collagen Synthesis in Rat Calvarial Cultures

Abstract: Insulin-like growth factors I and II (IGF-I and -II) are polypeptides secreted by skeletal cells and are considered regulators of bone formation. IGF-I and -II were studied for their effects on collagen synthesis and degradation in cultures of intact fetal rat calvariae and on type I collagen transcript levels in osteoblast-enriched (Ob) cells from fetal rat parietal bone. IGF-I and -II increased [3H]proline incorporation into type I collagen independently of their effect on cell replication. IGF-I and -II also decreased collagen degradation in calvarial cultures. Both factors had similar actions, although IGF-I stimulated collagen synthesis at 10 nM, and IGF-II at 30 nM. In Ob cells, IGF-I and -II also increased [3H]proline incorporation into type I collagen, but the effect was seen at 100 nM, and neither factor decreased collagen degradation. Slot blot analysis of IGF-I- and IGF-II-treated cells, using a rat type I collagen cDNA probe, revealed an increase in type I collagen transcripts. In conclusion, IGF-I and -II increase bone collagen synthesis and decrease collagen degradation in cultures of intact calvariae; the effect on collagen synthesis correlates with an increase in transcript levels in Ob cells.

Parathyroid hormone enhances the transcript and polypeptide levels of insulin-like growth factor I in osteoblast-enriched cultures from fetal rat bone.

Abstract: PTH stimulates bone resorption and formation, but the mechanism of its anabolic effect is unknown. The effects of PTH on bone formation could be mediated by local regulators, either by altering their binding to receptors or by modulating their synthesis. Cell extracts from PTH-treated osteoblast-enriched cultures isolated from fetal rat parietal bones were examined by Northern blot analysis for changes in mRNAs encoding insulin-like growth factor I (IGF-I), transforming growth factor-β, and β2-microglobulin. PTH did not influence transforming growth factor-β or β2-microglobulin transcript levels. In contrast, PTH-(1-34) had a biphasic stimulatory effect on IGFI transcript levels; 0.1-10 nM PTH increased IGF-I transcripts by 100-200% after a 6-h treatment, while 100 nM PTH induced a 100% increase. In addition, PTH at 0.01-10 nM increased immunoreactive IGF-I (iIGF-I) in culture medium by 40-200% at 24 h. Maximal increases in IGF-I transcripts occurred at 6 h, while iIGF-I accumulated throughout 24 h of cul...

Effects of platelet-derived growth factor on bone formation in vitro.

Abstract: Platelet-derived growth factor (PDGF) is a polypeptide found in a variety of tissues, including bone, where it could act as an autologous regulator of skeletal remodeling. Therefore, a recombinant B chain homodimer of human PDGF was studied for its effects on bone formation in cultured rat calvariae. PDGF at 10-100 ng/ml stimulated [3H]thymidine incorporation into DNA by up to sixfold and increased the DNA content and the number of colcemid-induced metaphase arrested cells. This effect was observed in the fibroblast and precursor cell-rich periosteum. As a result of its mitogenic actions, PDGF enhanced [3H]proline incorporation into collagen, an effect that was observed primarily in the osteoblast-rich central bone. The effect of PDGF was not specific for collagen since it also increased noncollagen protein synthesis. In addition, PDGF increased bone collagen degradation. PDGF and insulin-like growth factor (IGF) I had additive effects on calvarial DNA synthesis, but PDGF opposed the stimulatory effect of IGF I on collagen synthesis and IGF I prevented the PDGF effect on collagen degradation. In conclusion, PDGF stimulates calvarial DNA synthesis which causes an increased number of collagen-synthesizing cells, but PDGF also enhances bone collagen degradation.

Effects of fibroblast growth factors on deoxyribonucleic acid and collagen synthesis in rat parietal bone cells.

Abstract: Acidic fibroblast growth factor (aFGF) and basic FGF (bFGF) are related molecules that are extractable from bone matrix and may be important in the maintenance of normal bone physiology. The influence of each agent on DNA and protein synthesis was studied using bone-derived primary cell cultures. Both forms of FGF were relatively more mitogenic for bone cell populations with fewer osteoblastic (Ob) characteristics than for Ob-enriched cultures. However, in the Ob cultures, bFGF was intrinsically 10-fold more stimulatory than aFGF, whereas heparin enhanced the mitotic response only to aFGF. An optimal dose of either aFGF or bFGF (100 ng/ml) decreased alkaline phosphatase activity and increased the rate of noncollagen and collagen protein synthesis in Ob cultures. The stimulatory effect was relatively greater on noncollagen than on collagen synthesis, which resulted in a decrease in percent collagen synthesis. Neither factor altered the rate of collagen degradation. Furthermore, hydroxyurea diminished, but did not prevent, the stimulatory effect of each factor on rates of protein synthesis. In contrast, polyacrylamide gel analysis of newly synthesized protein and Northern blot analysis of steady state alpha 1 type I procollagen mRNA indicated differential effects by each agent on procollagen synthesis and processing. These studies suggest that the FGFs may produce their effects on Ob cells through both shared and disparate mechanisms, with the net result being a decrease in the expression of the osteoblastic phenotype.

Insulin-like growth factor (IGF) and bone.

Abstract: Bone is not only a rich source of a diverse group of growth factors, but is also a very responsive tissue to such growth promoting agents. IGF-I and IGF-I1 are reported to be synthesized and retain...

Platelet-Derived Growth Factor Enhances Deoxyribonucleic Acid and Collagen Synthesis in Osteoblast-Enriched Cultures from Fetal Rat Parietal Bone

Abstract: Platelet-derived growth factor (PDGF) or closely related proteins are found in bone matrix and are produced by cultured osteosarcoma cells. In serum-deprived osteoblast-enriched (ob) cultures from fetal rat bone, recombinant human PDGF (composed of a B chain homodimer) at 0.1-3 nM enhanced the rate of DNA synthesis by 2- to 8-fold within 24 h of treatment, and 0.3-3 nM PDGF increased cell number by 1.3- to 1.6-fold. Unlike results with rat kidney fibroblast cultures, the mitogenic effect of PDGF in ob cultures was not synergistic with that of insulin-like growth factor I. PDGF at 0.3-10 nM also enhanced the rates of collagen and noncollagen protein synthesis in ob cultures by 1.5- to 4.0-fold, and these increases were blocked when DNA synthesis was prevented. The stimulatory effects of PDGF did not appear specific to ob cultures from fetal rat bone, since similar increases were found in bone cell cultures containing fibroblasts and osteoblast precursors. PDGF binding at 4 C to ob cultures indicated a single class of receptors with a Kd of 0.16 nM and approximately 60,000 sites/cell. Polyacrylamide gel of 125I-PDGF bound and cross-linked to ob cultures revealed a single radioactive band at approximately 180,000-190,000 mol wt. The present studies, therefore, indicate that PDGF can directly increase replication and matrix protein synthesis by both differentiated and undifferentiated bone cells, and that bone- or platelet-derived PDGF may have an important anabolic role in bone remodeling or fracture repair.

Parathyroid Hormone-Related Protein Modulates the Effect of Transforming Growth Factor-β on Deoxyribonucleic Acid and Collagen Synthesis in Fetal Rat Bone Cells

Abstract: Proteins with biochemical function and sequence similarity to PTH are produced by many tumors associated with hypercalcemia and may have a role in pathological bone remodeling. Synthetic polypeptides comprising the aminoterminus of human PTH-related protein (PTH-rp) were examined for effects in intact fetal rat calvariae, and in osteoblastenriched (ob) cultures isolated from fetal rat parietal bone. In cultured calvariae, 0.5–5 nM PTH-rp stimulated [3H]thymidine incorporation into DNA by 25–70% after 24 h of treatment and decreased relative [3H]proline incorporation into collagen by 50%; the inhibitory effect on collagen production was not altered by hydroxyurea, which decreased DNA synthesis by 85%. PTHrp also increased [3H]hydroxyproline levels by 100% in culture medium from bones prelabeled with [3H]proline, indicating accelerated matrix turnover. In contrast to results in intact calvariae, PTH-rp had little effect on basal DNA and collagen synthesis in serum-deprived ob cultures. However, whe...

High school football injuries: a prospective study and pitfalls of data collection

Abstract: A 4 year prospective study (1982 to 1985) of high school varsity football injuries from the four Peoria high school football teams was undertaken Two hundred fifty-one injuries were recorded among a player population of 598, resulting in an injury rate of 421% per 100 players All of the players followed a prescribed preseason summer conditioning program that was endorsed by the Illinois High School Athletic Association The injuries were recorded on an athletic injury profile and entered into a computer for data analysis and retrieval The injury distribution by player position showed that halfbacks, tackles, linebackers, and guards had a higher risk of injury than other positions The knee was the body part injured most frequently (203%) A matrix of injuries to halfbacks was set up to examine the relationship of body part injured to type of play, time of injury, and activity during injury An anthropometric study using the Quetelet index did not reveal any correlation between injury and body size when the injured players were compared with the non-injured players Experience since 1969 has taught us many of the errors and pitfalls involved in injury surveillance Strict adherence to recording of data will ensure an accurate and useful injury surveillance program

Giant-celled glioblastoma of brain. A clinico-pathological and radiological study of ten cases (including immunohistochemistry and ultrastructure).

Abstract: Giant-celled glioblastoma multiforme is characterized by bizarre multinucleated giant cells with abundant eosinophilic cytoplasm, paucity of vascular endothelial proliferation, and increased reticulin fibers. It is considered by Rubinstein to be a variant of glioblastoma multiforme and by Zulch to be of mesenchymal origin. We studied retrospectively ten cases of giant-celled glioblastoma to correlate clinical and pathological features including immunohistochemistry and ultrastructure, radiology and survival time. Seven men and three women ranging in age from 23-75 years had variable clinical presentations and well defined lesions on computed tomography (eight patients). Well-defined at surgery, the tumor was located in temporal (six patients), frontal (three patients), and parieto occipital (one patient) lobes. Besides characteristic histology, glial-fibrillary acidic protein was positive in all, along with intracytoplasmic fibrils on electron microscopy. Three patients died within 3 days of surgery. Of the surviving seven treated with radiation and/or chemotherapy, three had a survival time of more than 36 months and four less than 15 months. Our study identifies this tumor to be of astrocytic lineage, with temporal lobe predilection, and overall a longer survival rate than glioblastoma multiforme.

Pneumatosis cystoides intestinalis and intramural intestinal gas.

Abstract: Gas in the bowel wall is an unusual but important finding on an abdominal radiograph The so-called “benign form,” pneumatosis cystoides intestinalis, may be asymptomatic or may cause a variety of symptoms and can result in a bowel obstruction or a sterile pneumoperitoneum On the other hand, intramural intestinal gas may represent severe underlying disease such as necrotizing enterocolitis or mesenteric vascular occlusion This finding should be sought when examining abdominal radiographs A thorough appreciation of the clinical significance of this unusual entity is necessary to make timely therapeutic decisions

Management of pain in children.

Abstract: There are now safe and effective techniques which can decrease significantly the amount of pain a child will experience in an acute care setting. For such techniques to work, however, the importance of pain management in children must be recognized. It should be assumed that anything that will hurt an adult will also hurt a child and that children are, in fact, often more sensitive to hospital procedures than are adults. Pain assessment should be a part of the child's care plan, and developmentally appropriate ways of recognizing pain should be in place in all hospitals that care for children. Behavioral and pharmacologic techniques should be tailored to the needs of the individual child. The skill of physicians should be assessed not only by their cure of illnesses, but by the comfort they provide in the process.

Effect of formula feeding on oral absorption of caffeine in premature infants.

Abstract: The systemic absorption of orally administered caffeine was evaluated in 16 premature infants receiving therapy for recurrent apnea. An oral bolus dose of caffeine (10 mg/kg) was given during a fasted state (n = 8) or immediately preceding formula (n = 8). The first-order absorption rate constant (ka) was estimated from the rise in the plasma concentration-time curve and extent of absorption was estimated by the area under the concentration-time curve. Therapeutic concentrations of caffeine were achieved rapidly followed by very slow elimination of drug. No difference between the fasted and fed groups was found in the apparent rate or extent of caffeine absorption, suggesting that caffeine can be administered concomitantly with feedings.

The impact of nurse managed care on the cost of nurse practice and nurse satisfaction.

Abstract: How are costs of nursing care effected when professional nurses practice nursing based on patient's needs as opposed to institutional policy? The author discusses a different nursing care delivery system that builds on primary nursing but frees the nurse from institutional constraints. The results were a 20 percent decrease in nursing costs and increased satisfaction among the nursing staff participants.

Two false-negative results using morphine sulfate in hepatobiliary imaging.

Abstract: Morphine sulfate has been used in hepatobiliary imaging to cause contraction of the sphincter of Oddi, thereby increasing pressure in the biliary tree. If the cystic duct is patent, the increased pressure usually causes bile to flow into the cystic duct with filling of the gallbladder. Using this technique, the authors have encountered two false-negative cases. Both patients received 0.04 mg/kg of morphine sulfate intravenously, 40 minutes after the intravenous administration of 5 mCi of technetium 99m-DISIDA. Although both patients filled their gallbladders within 1 hour, they both underwent surgical exploration because of high clinical suspicion of acute cholecystitis. Both were found to have acute cholecystitis.

Laser angioplasty of totally occluded coronary arteries and vein grafts: preliminary report on a current trial.

Abstract: CLINICAL PERSPECTIVE: Among the various laser angioplasty systems and atherectomy devices currently in clinical trials, the Lastac system appears to be particularly suitable for treating totally occluded coronary arteries and vein grafts. Preliminary results of a clinical trial in more than 35 patients show a recanalization rate of 92% and no complications attributable to the laser. Restenosis has occurred in five cases; in three of these, the arteries were reopened with laser or conventional angioplasty.

Von Willebrand factor and von Willebrand's disease: a complex protein and a complex disease.

Abstract: Von Willebrand factor is a complex protein which is important in several ways for normal hemostasis. Von Willebrand's disease results when there is either a quantitative or qualitative disorder of von Willebrand factor. In this review, the structure and function of von Willebrand factor are discussed. Additionally, the current laboratory and clinical classification of von Willebrand's disease and closely related variants are outlined.

Clinical experience with the use of the angled-balloon dilatation catheter.

Abstract: A special balloon catheter has been developed for use in coronary angioplasty. The balloon portion has a 135 degrees - 145 degrees angle at its mid portion. It is designed for stenosis located at an angle of the coronary artery. We investigated the use of this catheter in 39 patients who underwent percutaneous transluminal coronary angioplasty (PTCA): 29 men and 10 women. PTCA was attempted in 43 stenotic sites. Thirty-two stenoses were located at the angled portion of the dilated arteries. Eleven stenoses were located at the side branches of the acutely angled bifurcations. Twenty stenoses were in the right coronary artery distribution. Twenty-two stenoses were in the left coronary artery distribution. One stenosis was at the origin of the left internal mammary artery. Forty-one stenoses were angioplastied successfully (95.4%). No angiographic evidence of intimal tear or dissection was noted in all of the dilated vessels. Acute closure was not observed. The mean follow-up period was 239.5 days. Six patients (15.4%) were found to have restenosis. We conclude that the use of the angled-balloon dilatation catheter provides the potential benefit of reducing intimal trauma and dissection during PTCA of certain coronary anatomies--stenosis at the angled portion or at the takeoff of the side branch of a bifurcation.

Isolation of monocyte-depleted and monocyte-rich fractions from human mononuclear cells

Abstract: Utilizing a recently reported characteristic of monocytes to aggregate in cold, a new procedure for obtaining monocyte-rich and monocyte-depleted mononuclear fractions from human blood is described. After aggregation in cold and adherence to plastic, a fraction containing 88% monocyte (LeuM3 CD14+) is obtained. After treating the supernatant, which separates from the aggregates, with a monocyte lysosomotropic agent (L-Leucine Methyl Ester), a fraction containing 0% monocyte (LeuM3 CD14+) and 88% lymphocytes (Leu4 CD3+ and Leu 12 CD19+) is obtained. In round-bottom culture wells, this monocyte-depleted fraction produced immunoglobulins in response to pokeweed mitogen (5,826 +/- 2,356 IgM micrograms/ml), to a degree not significantly different that that produced in the presence of monocytes (7,426 +/- 3,347 IgM micrograms/ml). This suggests the presence of cells in the lymphocyte fraction, that are not monocytes but are capable of antigen presenting.

A continuum of care from hospital to community

Abstract: This study evaluates the impact of deinstitutionalization on a multiorganizational inpatient and outpatient treatment system. Data are presented on the system's use by 613 patients over an 8 1/2 year period. Goals of a deinstitutionalization program, increasing outpatient service utilization and decreasing rehospitalization, were not clearly achieved. The needs of an inpatient and outpatient care system include effective communication between systems of care, provisions for patient drift from one community to another, and outpatient services of sufficient breadth and quantity to meet the needs of various service users, particularly the severely disabled.