Showing papers by "University of Louisville published in 1993"

Handbook of microbiological media

Abstract: Preface. Preparation of Media. Media Formulations, Preparation, and Uses. Appendices. Index.

Behavior-based and outcome-based salesforce control systems

Abstract: The authors develop a conceptual model depicting relationships between salesforce control systems, characteristics, performance, and sales organization effectiveness as a framework for testing the ...

Novel role of human chorionic gonadotropin in differentiation of human cytotrophoblasts

Abstract: Our laboratory previously demonstrated that cytotrophoblasts and syncytiotrophoblasts in human placental tissue contain hCG/LH receptors. From this finding, we postulated that one role of hCG might be to promote the differentiation of cytotrophoblasts into syncytiotrophoblasts. To test this postulate, cytotrophoblasts were isolated from human term pregnancy placentas and cultured with and without increasing concentrations of highly purified hCG. The results showed that hCG had a biphasic effect on 1) the aggregation of cells without intervening plasma membranes; 2) the expression of cadherin, a cell adhesion receptor that facilitates cellular aggregation; 3) the expression of hCG/LH receptor gene; and 4) the expression of three different hormonal markers of differentiation. The hCG effects were time and dose dependent and hormone specific. The addition of excess polyclonal hCG antibody, but not normal rabbit serum or nonspecific antirabbit immunoglobulin G, decreased basal responses as well as those to exogenous hCG. The polyclonal hCG/LH receptor antibody increased differentiation and dramatically stimulated hCG secretion in the presence or absence of exogenous hCG. (Bu)2cAMP mimicked the actions of hCG. H-89, a protein kinase-A inhibitor, decreased basal as well as exogenous hCG responses. Calphostin, a protein kinase-C inhibitor and lavendustin, a tyrosine kinase inhibitor, on the other hand, had no effect. In summary, it is novel that hCG made in human placenta can regulate the differentiation of cytotrophoblasts, which make little hCG, into syncytiotrophoblasts, which make considerable amounts of hCG.

Field and observer modes of remembering.

Abstract: Nigro and Neisser (1983) contrasted two ways of remembering personal experiences: the rememberer may 'see' the event from his or her perspective as in normal perception, or 'see' the self engaged in the event as an observer would. Several factors contribute to the determination of perspective, but Nigro and Neisser also reported that many subjects claimed they could change to another perspective at will. We sampled personal memories from several life periods and assessed ability to change the initially reported perspective. Changing was easier for recent or vividly recalled events, harder for older and less vividly recalled events. Memory perspectives may differ in other aspects than their imagery. A second study was conducted to determine whether affective experience is altered when perspectives are changed. The affect experienced decreased when shifting from a field to an observer perspective, but did not change with the converse shift. These studies provide further evidence that remembering is more than retrieval. The information that enters awareness is determined by the information sources in memory and the organisational scheme adopted for recollection.

Novel expression of human chorionic gonadotropin/luteinizing hormone receptor gene in brain.

Abstract: LH from anterior pituitary and hCG from placenta bind to a common receptor in gonadal and nongonadal reproductive tissues. There have been numerous examples suggesting that the brain may also contain hCG/LH receptors, yet there has been no evidence for their existence so far. We now demonstrate by reverse transcription-nested polymerase chain reaction and northern blotting that the rat brain contains hCG/LH receptor mRNA. A major receptor transcript of 2.6 kilobases and minor transcripts of 1.8 and 4.4 kilobases were found. Western immunoblotting, ligand blotting, and covalent receptor cross-linking studies have shown that rat brain also contains an 80-kilodalton receptor protein that can bind hCG and hLH, but not hFSH. Rat testis used as a positive control showed a higher abundance of multiple transcripts and an 80-kilodalton receptor protein that can bind [125I]hCG. Rat liver used as a negative control did not contain any receptor transcripts or protein. In situ hybridization, dot blotting, immunocytochemistry, and topical autoradiography have revealed that hCG/LH receptors are present in rat hippocampus; dentate gyrus; hypothalamus; cerebellum; choroid plexus; ependymal cells of third, fourth, and lateral ventricles; cortex; brainstem; bovine hypothalamus; and human area postrema. These novel findings could potentially explain numerous previous observations and suggest new possibilities concerning the regulation of brain functions by hCG and LH.

Effects of Gender Role Expectations on the Social Support Process

Abstract: Based on a model of interactive coping activation, we review the impact of gender in the giving and receiving of emotion- and problem-focused social support. The research suggests that the female role (emphasizing nurturance and emotional expressiveness) makes it easier for women to activate social support from close relations as well as to provide social support; whereas the male role (emphasizing achievement, autonomy, emotional control) makes it difficult for men to seek and obtain social support. Type of support required (social-emotional vs. instrumental) may moderate when men and women are more effective in providing social support. The gender-linked model of social support activation may be useful in diagnosing interpersonal problems in providing and obtaining social support.

Interleukin-1 and bone metabolism: a review.

Abstract: This review discusses the effects of interleukin-1 (IL-1) on bone metabolism and the evidence implicating IL-1 in periodontal disease. IL-1 is a potent cytokine with significant effects on the metabolism of many tissues, including bone. Several in vitro and in vivo studies have established the potent bone-resorbing effect of IL-1. Studies have indicated that IL-1 inhibits bone formation, although it can stimulate formation under certain conditions. Osteoblastic cells are the bone cells expressing IL-1 receptors and responding to IL-1. IL-1 effects on osteoblastic cells include stimulation of prostaglandin formation and modulation of gene expression of several proteins (cytokines, enzymes, enzyme inhibitors, matrix proteins, etc.). Osteoblastic cells also produce IL-1, suggesting an autocrine/paracrine function of IL-1 in bone. IL-1 has been shown to interact with other osteotropic factors, both systemic and local. These interactions modulate the effects of IL-1 on bone. The IL-1 effects on bone metabolism, along with other observations, suggest that IL-1 may be involved in the pathogenesis of bone diseases. Evidence from in vivo and in vitro studies suggests that IL-1 is an important factor in periodontal tissue breakdown. The ability of periodontopathic bacteria to stimulate IL-1 production, the detection of elevated IL-1 levels in periodontally-diseased tissues, and the effects of IL-1 on cells of the periodontium provide a plausible sequence of events in the pathogenesis of periodontal disease. Finally, therapeutic modalities aimed to control the actions of IL-1 are also discussed.

Decelerating growth and human breast cancer

Abstract: Background. Improved understanding of human breast cancer growth rates may have many clinical applications. Previous reports have used small numbers of patients and assumed an exponential growth rate. Methods. The exponential equation and the most commonly used decelerating growth equations, the Gompertz equation and seven generalized forms of the logistic equation, were fitted to mammographic measurements of primary breast cancer using the least squares method. An average of 3.4 observations was made in 113 patients, whereas two measurements were made in another 335 patients. Tumors were assumed to originate as a single cell with the lethal tumor volume assumed to be 240 cells. Results. All decelerating equations tested provided a better fit than the exponential, whereas a form of the logistic equation provided the best fit to the data. Limitations in the number of tumor measurements, the assumption of maximal tumor size, and biases inherent in the method of data collection are reviewed. These observations suggest families of curves that characterize breast cancer growth during the early period of clinical observation. Conclusions. Breast cancer growth in the early clinical period was modeled by a form of the logistic equation. The exponential equation fit the data least well.

Intramedullary supracondylar nailing of femoral fractures. A preliminary report of the GSH supracondylar nail.

Abstract: From 1987 through 1990, 34 acute supracondylar femoral fractures in 33 patients were treated with an interlocking closed-section intramedullary nail inserted retrograde into the femur through the intercondylar notch. Follow-up data of at least five months were available for 25 of these fractures. The patients suffered injuries more extensive than comparable patients reported in the literature. All fractures healed clinically and radiographically. The average arc motion at the most recent evaluation was 100 degrees. The average operative time was 156 minutes and the average estimated blood loss was 224 ml. Complications related to this treatment were successfully resolved. The genucephalic nail is a good treatment for supracondylar femoral fractures.

Microvascular effects of complement blockade with soluble recombinant CR1 on ischemia/reperfusion injury of skeletal muscle.

Abstract: Reperfusion of ischemic tissue is associated with tissue injury greater than that resulting from ischemia alone. C activation has been hypothesized to mediate the so-called ischemia/reperfusion injury through both membrane attack and C5a-dependent recruitment of neutrophils to sites of C3 fixation on the endothelium via C3 receptors. Adherence of neutrophils is preconditional to expression of their deleterious effects, which are central to the pathophysiology of ischemia/reperfusion injury. This study was designed to evaluate the effect of inhibition of C activation on ischemia/reperfusion injury using a soluble and truncated recombinant human CR1 (sCR1) molecule, a "tail-less" form of the membrane C3b/C4b receptor (CD35) that functions as a regulator of C activation. Capillary perfusion and leukocyte adherence to venular endothelium were measured after reperfusion in a mouse cremaster muscle model that allowed microscopic video observation of microcirculatory changes. Infusion i.v. with sCR1 before a 4-h period of ischemia and during a 3-h subsequent period of reperfusion prevented the increase in leukocyte adherence to venular endothelium seen in controls, and enhanced the number of reperfusing capillaries by 55%. Trypan blue staining showed an increase in muscle cell viability from 11 to 50% in mice receiving sCR1 as compared to controls. Tests of blood samples from mice infused with sCR1 demonstrated nearly complete inhibition of the mouse alternative pathway of C activation, but no detectable loss of the mouse classical pathway of C activation. It was concluded that C activation in this model of skeletal muscle injury is likely to be due to the alternative pathway, and that inhibition of C activation during reperfusion inhibits leukocyte adherence to blood vessel walls and protects the capillary microcirculation.

Novel coexpression of human chorionic gonadotropin (hCG)/human luteinizing hormone receptors and their ligand hCG in human fallopian tubes

Abstract: The human uterus, including its blood vessels, contains hCG/human LH receptors. We now demonstrate that human fallopian tubes also contain a 4.4-kilobase hCG/LH receptor mRNA transcript and an 80-kilodalton immunoreactive protein that can bind [125I]hCG. Tubal mucosa contain more receptor transcripts, receptor protein, and [125I] hCG binding than the tubal smooth muscle or blood vessels. Human fallopian tubes also contain hCG protein and a 0.6-kilobase hCG alpha mRNA transcript. However, very little hCG is found in tubal cell layers other than mucosa. Ampullary segments contain more hCG/LH receptors and hCG than isthmus. Secretory phase tubes contain more than proliferative phase, postpartum, or postmenopause tubes. Incubation with highly purified hCG resulted in an increase in catalytically active 5-lipoxygenase, cyclooxygenase-1, and cyclooxygenase-2 enzymes in tubal tissues. In summary, human fallopian tubes, which have never previously been considered a direct target of hCG/LH action, express function...

Proton motive force may regulate cell wall-associated enzymes of Bacillus subtilis.

Abstract: Bacterial metabolism excretes protons during normal metabolic processes. The protons may be recycled by chemiosmosis, diffuse through the wall into the medium, or bind to cell surface constituents. Calculations by Koch (J. Theor. Biol. 120:73-84, 1986) have suggested that the cell wall of gram-positive bacteria may serve as a reservoir of protons during growth and metabolism, causing the wall to have a relatively low pH. That the cell wall may possess a pH lower than the surrounding medium has now been tested in Bacillus subtilis by several independent experiments. When cultures of B. subtilis were treated with the proton conductors azide and carbonylcyanide m-chlorophenylhydrazone, the cells bound larger amounts of positively charged probes, including the chromium (Cr3+) and uranyl (UO2(2+) ions and were readily agglutinated by cationized ferritin. In contrast, the same proton conductors caused a decrease in the binding of the negatively charged probe chromate (CrO4(2-)). Finally, when levansucrase was induced in cultures by the addition of sucrose, the enzyme was inactive as it traversed the wall during the first 0.7 to 1.0 generation of growth. The composite interpretation of the foregoing observations suggests that the wall is positively charged during metabolism, thereby decreasing its ability to complex with cations while increasing its ability to bind with anions. This may be one reason why some enzymes, such as autolysins, are unable to hydrolyze their substrata until they reach the wall periphery or are in the medium. Images

The two-edged sword of large-dose steroids for spinal cord trauma.

Abstract: Objective In 1990, large-dose steroid administration was advocated in spine-injured patients to lessen neuroloqic deficits. The authors undertook both prospective and retrospective studies to evaluate the response of such profound pharmacologic intervention. Summary Background Data Of all sources of nonfatal injury, spinal cord trauma remains the most devastating in both cost and impact on the quality of the patient's life. One study found that routine large-dose steroid administration after injury lessened the extent of neurologic injury. After uncommonly prompt and broad lay press publicity, this practice was widely accepted. Biased by knowledge of the known immunosuppressive effects of steroids, the authors suspected that pneumonia was both more frequent and severe in steroid-treated patients

Parastatin (porcine chromogranin A347-419), a novel chromogranin A-derived peptide, inhibits parathyroid cell secretion

Abstract: Chromogranin A (CgA), previously referred to as secretory protein- I, is a 50-kilodalton protein present in secretory granules of many endocrine and neuroendocrine cells. In the parathyroid it is present and cosecreted with PTH in response to hypocalcemia. CgA appears to be a precursor of bioactive peptides including pancreastatin, P-granin, vasostatin, and chromostatin. The presence of several highly conserved pairs of basic amino acids, putative cleavage sites, in the CgA molecule suggests that other yet unidentified bioactive peptides might exist within the molecule. We tested this speculation by subjecting porcine parathyroid CgA to digestion by endoproteinase Lys-C. Resulting CgA- derived peptides were isolated by reverse-phase Cl8 HPLC and tested for their ability to affect low-Ca*+ stimulated secretion by porcine parathyroid cells. We characterized one peptide, which we named parastatin, that inhibited secretion of both PTH and CgA in a dose- dependent fashion over the range of 0.2-0.6 pM. Parastatin migrated as a single band on sodium dodecyl sulfate-polyacrylamide gel electro- phoresis with an apparent mol wt of 11,000. Edman degradation yielded the sequence L-S-F-R-A-P-A-Y-G-F-R-G-P-G-L corresponding to res- idues 347-361 of porcine CgA. Amino acid analysis of endoproteinase Lys-C and endoproteinase Asp-N-generated fragments indicated that parastatin corresponds to residues 347-419 of CgA. A synthetic NH,- terminal fragment of rat parastatin corresponding to residues I-19 was as inhibitory as intact porcine parastatin on parathyroid gland secre- tion. These results extend the concept that CgA is a precursor of biologically active peptides. (Endocrinology 133: 461-466, 1993)

Basicranial Evidence for Early Mammal Phylogeny

Abstract: The distribution of thirty-eight basicranial characters is considered among monotremes, marsupials, placentals, and the following extinct taxa—Tritheledontidae, Tritylodontidae, Sinoconodon, Morganucodontidae, Haldanodon, Triconodontidae, Multituberculata, and Vincelestes. PAUP analysis of the ensuing data matrix supports the following conclusions: 1. Marsupialia and Placentalia form a clade supported by an anterior lamina of the petrosal that is greatly reduced or absent, a cavum epiptericum floored primarily by the alisphenoid, major basicranial drainage via the postglenoid foramen, and a squamosal contributing broadly to the cranial wall. 2. A clade with Vincelestes from the Early Cretaceous of Argentina as the sister taxon to Marsupialia plus Placentalia is supported by a caudal tympanic process of the petrosal, a post-promontorial tympanic sinus, a true cochlear aqueduct, and a cochlear duct coiled through at least 270 degrees. 3. A clade comprising the taxa in (2) along with Multituberculata plus Monotremata is supported by loss of support for the ventromedial part of incus on the cranium and a greatly reduced quadrate ramus of the alisphenoid. A clade with Multituberculata and Monotremata is supported by a common tympanic aperture for the prootic canal and pterygoparoccipital foramen. 4. A clade including Triconodontidae and the taxa in (3) is supported by loss of the vascular foramen in the periotic lateral flange and the suspension of the postdentary bones from the cranium. 5. A clade with Haldanodon and the taxa in (4) is based on the loss of the quadratojugal notch in the squamosal. 6. A clade including the taxa in (5) plus Sinoconodon and Morganucodontidae is supported by an anterior lamina of the petrosal expanded forward dorsal to the exit of the maxillary and mandibular nerves, a cavum epiptericum partially floored by the petrosal, facial ganglion floored by petrosal, stapes length less than 5.5% of skull length, ossified base of the pila antotica absent, major basicranial drainage via a large prootic canal that opens endocranially, a paroccipital process with a distinct ventrally directed projection for muscle attachment, a petrosal promontorium, and a well-developed dentary-squamosal contact. 7. Tritylodontidae shares support of the ventromedial part of the quadrate on the cranium via a convex surface on the crista parotica of the petrosal and a fossa for the stapedius muscle on the petrosal with the taxa in (6).

The role of local antibiotic therapy in the management of compound fractures.

Abstract: Seven hundred four compound fractures (198 [28%] Grade I, 259 [37%] Grade II, and 247 [35%] Grade III) were treated during a seven-year period at the author's institution. One hundred fifty-seven open fractures (22%) (Group A) received systemic antibiotic prophylaxis only, whereas 547 compound fractures (78%) (Group B) were treated with local application of antibiotic beads (tobramycin) in addition to prophylaxis. Fracture grades, age, gender, fracture location, and length of follow-up period were not significantly different between the two groups. All fractures underwent timely irrigation, debridement, and skeletal stabilization. Forty-nine of 704 compound fractures (7%) developed an infection (acute wound infection or chronic osteomyelitis or both). Group A showed an infection rate of 17% (26/157); treatment in Group B resulted in 23 compound fracture infections (4.2%). The difference in the incidence of infection was statistically significant. Comparison of the infection rates in either wound infection or chronic osteomyelitis showed a trend toward decreased rates in Group B versus Group A throughout all fracture grades. However, by subdivision into the fracture grades, only the IIIB types had a statistically significant decrease of infection in Group B versus Group A; the wound infection rate was 39% (9/23) in Group A and 7.3% (7/96) in Group B. The rate of chronic osteomyelitis was 26% (6/23) in Group A and 6.3% (6/96) in Group B. Prophylactic use of antibiotic-laden PMMA beads in addition to systemic antibiotics was of benefit in preventing infectious complications in compound fractures, in particular in Type IIIB open fractures.

Topical ophthalmic beta blockers: a comparative review

Abstract: Topically administered beta blockers are the preferred medical therapy for glaucoma. These agents reduce intraocular pressure (IOP), thereby preventing damage to the optic nerve and the subsequent loss of vision. Timolol, betaxolol, levobunolol, metipranolol, and carteolol are the topical beta blockers available in the U.S. They have similar IOP-lowering efficacy, but differ in other pharmacological properties. Topically administered beta blockers are generally well tolerated. They undergo systemic absorption, however, and can adversely affect cardiovascular and bronchopulmonary function in patients with existing diseases such as heart failure, sinus bradycardia, chronic obstructive airways disease, or asthma. Betaxolol, which is beta1-selective, and carteolol, which has intrinsic sympathomimetic activity (ISA), may have systemic tolerability profiles superior to the traditional nonselective, non-ISA beta blockers. These hypotheses require confirmation in controlled clinical trials. Local adverse...

Lymphocyte subset responses to trauma and sepsis.

Abstract: One hundred five trauma patients admitted to three trauma centers with injury Severity Scores of 20 or greater had lymphocyte phenotypic subsets characterized throughout their hospital course. Total lymphocytes, pan-T (CD2), helper T (CD4), suppressor T (CD8), pan B (CD20), and DR expressing lymphocytes were quantitated by monoclonal antibodies and flow cytometric analysis. Results were analyzed between three patient groups: uninfected, uneventful recovery (n = 64); major infection (n = 26); and dead (n = 15; 7 with sepsis). A significant lymphopenia, maximal at 3 days, occurred in the first postinjury week compared with controls (p < 0.05), which recovered over the study period. A hierarchical distribution was found between the three outcome groups with the lowest numbers of several lymphocyte phenotypes in those who died. T helper and suppressor cells were similarly affected, but lowest in patients destined to develop infection or die. The helper-suppressor ratio, however, was similar in all three outcome groups. Therefore, modulation early after injury aimed at restoring these subsets may reduce the risk of subsequent infection.

Human myometrial smooth muscle cells are novel targets of direct regulation by human chorionic gonadotropin.

Abstract: Human myometrium contains receptors for hCG/human LH (hLH). This suggested the possibility that hCG and hLH might regulate human myometrium, which has not previously been considered a direct target of gonadotropin regulation. To investigate such a possibility, highly pure and viable smooth muscle cells were isolated from nonpregnant human myometrium and cultured as monolayers. The cells contained hCG/LH receptor mRNA transcripts and a 50-kDa immunoreactive protein that can bind 125I-hCG in a ligand-specific manner. The presence of hCG during culture resulted in a significant increase of myometrial smooth muscle cell density. The hCG effect was time- and concentration-dependent and was mimicked by hLH but not by human FSH or human FSH or human thyroid-stimulating hormone. Human CG also greatly increased the size of a subpopulation of myometrial smooth muscle cells without affecting their chromosomal ploidy. Antibodies to hCG/LH receptors and hCG blocked hCG effects. Human prolactin and growth hormone, which do not bind to hCG/LH receptors, also increased the myometrial smooth muscle cell density. A protein kinase A inhibitor (H-89) blocked hCG response whereas calphostin (a protein kinase C inhibitor) and lavendustin A (a tyrosine kinase inhibitor) had no effect on hCG response, suggesting that a cAMP/protein kinase A signaling mechanism is involved in hCG action. Eicosanoids from cyclooxygenase and 5-lipoxygenase pathways of arachidonic acid metabolism are probably not involved, because the inhibitors of these enzymes had no effect on hCG response. While progesterone and estradiol could not mimic or modify hCG action, epidermal growth factor did mimic hCG in increasing myometrial smooth muscle cell density.(ABSTRACT TRUNCATED AT 250 WORDS)

Consensus review of the clinical utility of DNA flow cytometry in neoplastic hematopathology

Abstract: Numerous prospective (fresh tissue) and retrospective (archival tissue) studies of DNA flow cytometry have been undertaken to ascertain the biologic behavior of hematopoietic malignancies. We have critically examined most of the studies that relate DNA ploidy and proliferative activity to clinical outcome in nonHodgkin’s lymphomas, acute leukemias, and multiple myeloma. Selected studies relating DNA flow cytometry to histologic grade, but not clinical outcome, of nonHodgkin’s lymphomas were also considered. The goal was to reach a consensus, based on a review of the literature and on our collective experience, on the value of DNA flow cytometry in the characterization of hematopoietic malignancies. The following review of the literature covers lymphomas, multiple myelomas, and acute leukemias.

Laser etching of enamel for direct bonding

Abstract: The application of laser irradiation to etch dental enamel in preparation for direct bonding of orthodontic appliances has been studied. Forty extracted human teeth were divided into four groups of 10 teeth. Within each group, five teeth were subjected to a 30 sec acid etch of the buccal enamel surface; the other five in each group were etched with a laser. Four power settings on the laser etching unit were used: 80mJ, 1W, 2W and 3W. After etching, brackets were adhered to the prepared buccal enamel surfaces with composite resin. Shear bond strength was tested 7 days later. The findings showed that an acceptable shear bond strength, viz. ≥0.6kg/mm, could be achieved at laser power settings of 1 to 3W but not at the lowest setting (80 mJ). However, the mean shear bond strengths obtained with laser treatment of the enamel at 80mJ, 1W and 2W were lower (p<0.01 or 0.001) than that achieved with acid etching.