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The nonpolymeric high molecular weight substances such as lanolin alcohol, stearyl alcohol, and cetyl alcohol have been investigated for their film-forming potential. Furthermore, the application of this potential in the design of topical drug-delivery systems has also been explored. The utilization of such film-forming systems may offer certain unique advantages not associated with the polymeric systems. Stearyl alcohol and cetyl alcohol do not form films of acceptable integrity. Lanolin alcohol forms thin films capable of being isolated. Inclusion of appropriate amounts of ethyl cellulose and propylene glycol or hexadecyl alcohol in lanolin alcohol was found to improve the integrity, hardness and modulus of elasticity of these films. These lanolin alcohol films have been shown to reduce the normal in vivo transepidermal moisture loss. The in vitro release of 3H--triamcinolone acetonide from selected films was investigated. The results suggest that the drug release follows a diffusion-controlled granular matrix model with the release profile proportional to the square root of time. The release rate constants were found to be proportional to the concentration of the dispersed drug. Drug release was found to be maximal from a system containing the drug in a near-saturated solution. In vitro penetration experiments using human cadaver skin were also conducted from the same matrix-forming compositions. The analysis of the penetration data revealed that the release from the matrix acted as the rate-limiting step for the penetration process. The maximum rate of penetration was observed from a system containing slightly excess solubilizer than required to completely solubilize the steroid. The importance of this finding has been explained.

This study investigated the effectiveness of psychosocial treatment in reducing stress, improving mood and enhancing immune functioning in gay males diagnosed HIV seropositive. A J & J I-30 Biofeedback System monitored muscle potential, respiration, heart rate, electrodermal response and temperature during sessions where participants received training and/or were subject to a stress profile. Home practice tapes were provided. Results showed a delayed treatment effect in reducing stress and symptom severity and improving mood for two participants. One participant showed improvement in hardiness. Stress Profile results showed decreases in muscle potential during stress for three participants. All participants improved during recovery. During EMG biofeedback sessions, two participants improved. Within sessions, immune functioning improved for three participants. Overall, results suggest that participants learned skills that enabled them to better adapt to stress, and access, perhaps through a change in consciousness, some mechanism through which immune functioning improved in the short term. (Abstract shortened with permission of author.)

Purpose. The purpose of this study was to determine if differences existed in the perceptions of re-entry nurses, nurse educators, and nurse administrators with regard to the needs of women who wish to become re-employed in the nursing field. Specific barriers to re-entry and perceived needs in terms of skills and knowledge were examined. Procedure. The sample for the study included inactive nurses, nurse educators and nurse administrators from 13 counties within California. The inactive nurse (re-entry) group was selected from the rosters of three continuing education programs. The nurse educator and nurse administrator groups were randomly selected from a population of names provided by the Board of Registered Nurses and the State Department of Health. A Re-entry Nurse Questionnaire was used for data collection. This three-part questionnaire was designed to assess the barriers to re-entry and the knowledge and skills deemed important for re-entry. Analysis of variance (ANOVA) and the Tukey method of multiple comparisons were used to determine significant differences among the groups. Findings. There were significant differences in the perceptions among the three groups with regard to one half the barriers to re-entry and three of the knowledges and eight of the skills important for re-entry. Recommendations for Further Research. It is recommended that further research include: (1) studies to evaluate the self confidence level of nurses who have returned to nursing, (2) an analysis of the relationships between re-entry and employed nurses, (3) a pilot study for a model re-entry program established within the present educational structure, and (4) an analysis of the viability of the intermittent contractual agreement for nursing manpower planning.

Aryl hydrocarbon receptor nuclear translocator (Arnt) belongs to the basic helix-loop-helix/Per-Arnt-Sim protein family. Our lab is interested in identifying the protein factors that modulate the Arnt-dependent pathway. We identified a novel Arnt-interacting peptide Ainp2 with an estimated size of 9 kDa. The endogenous Ainp2 protein is not found in MCF-7 cells. Another protein that is of interest to us is β-tubulin. Beta-tubulin is the monomeric subunit of microtubules. I have presented my thesis in two parts: the first part is focused on Ainp2 and the second part is on β-tubulin. The purpose of the first part of my thesis was to investigate whether Ainp2 affects the Arnt-dependent estrogen receptor (ER) pathway via an Arnt-related mechanism. Transient transfection studies in MCF-7 cells revealed that transfected Arnt increases E2-induced, ERE-driven luciferase activity in a dose-dependent manner; however, the enhancement effect of Arnt is significantly suppressed in the presence of Ainp2. The Ainp2 protein was successfully expressed in Sf9 cells and was affinity purified by the TALON metal resin method. Data from co-immunoprecipitation experiments showed that Ainp2 suppresses the interaction between Arnt and ERα in the presence or absence of E2. The aim of the second part of my thesis was to explore the effect of β-tubulin on the Arnt-dependent aryl hydrocarbon receptor (AhR) pathway. My data indicates that human β4-tubulin inhibits 3MC-driven, AhR-dependent luciferase expression. This suppressive effect of β4-tubulin is likely caused by a reduction in the nuclear Arnt content resulting from Arnt retention in the cytoplasm. The findings are certainly intriguing that the Arnt-mediated pathway can be modulated by either Ainp2 or β-tubulin. Limiting the nuclear Arnt function can be an approach to block Arnt-dependent signaling events which are crucial for cancer growth. These findings provide a means for rational drug development.

Powdered aerial parts of the weed yellow starthistle (Centaurea solstitialis, Compositae) and the methanol extract, alkaloidal and fatty fractions of the methanol extract of the aerial parts, injected intraperitoneally, produced a highly significant hypothermia in conscious normal rats. Other significant symptomatology included sedation, decreases in spontaneous motor activity, depressed respiration, mydriasis, ear blanching, enophthalmos and anuria. Four sesquiterpene lactones of the guaianolide type (repin, solstitialin-A, janerin and cynaropicrin), constituents of yellow starthistle, showed similar activities in rats. The predominant effects were hypothermia, sedation and enophthalmos. Both repin and janerin, in equidoses of 3.1-31 mg/kg, produced similar profiles of generalized effects and hypothermia, whereas solstitialin-A and cynaropicrin did not show well-defined dose-response relationships. The lethal doses of the methanol extract, repin, solstitialin-A, janerin and cynaropicrin were 1000, 31, 310, 31 and 310 mg/kg, respectively. Studies were carried out to document the effects of various potential antagonists and agonists on the repin-induced hypothermic effect. Rats were pretreated intraperitoneally with atropine sulfate (10 and 20 mg/kg), atropine methylbromide (20 mg/kg), propranolol (10 and 20 mg/kg), metergoline (0.5 mg/kg), ketanserin tartrate (0.2 mg/kg), diphenhydramine HCl (10 mg/kg) and apomorphine HCl (0.5 mg/kg). No significant effects of pretreatment were evident up to 2 h but statistically significant partial reversals of repin-induced hypothermia by atropine sulfate (20 mg/kg), metergoline, ketanserin, diphenhydramine and apomorphine were observed beginning 3 h after repin injection. Propranolol pretreatment resulted in a significant potentiation of repin's hypothermic effect. The sleeping time in mice induced by intraperitoneal sodium pentobarbital was markedly potentiated by pretreatment with repin. Receptor binding studies showed that repin facilitated the binding of GABA$\sb{\rm A},$ bombesin and neuropeptide Y without any significant binding of repin to any of the 36 receptors and binding sites tested.

The presence of contaminants in parenteral solutions is a constant nemesis against which pharmaceutical manufacturers, as well as medical, pharmacy , and nursing practitioners mus t vigilantly struggle to provide quality health care. At each level in the parenteral drug delivery system, contamination is possible before the patient actually receives the infusion. The implementation of better practices and procedures continues in the quest of contaminant-free parenterals, nevertheless, the literature is replete with articles documenting contamination of parenteral medication. Foreign body particulate matter has been found sequestered in the lungs of patients who have received intravenous therapy. The entrapment of foreign bodies can occur in other body organs besides the lungs. The hazardous effects of this particulate matter has been the subject of much concern. Other forms of parenteral contaminants have been reported in the literature. These include both bacterial and fungal contaminants. Contaminant detection in parenteral solutions has been accomplished by several methods. These have included: visual inspection, nephelometric methods, methods of membrane filtration with subsequent microscopic examination, and methods employing various electronic adaptations. No references have been published describing viral contamination of parenterals or methods for viral detection in parenteral solutions . Yet, viral contaminants infused directly into the blood of a patient may be of grave clinical significance. Thus, the objective of this project was to develop a method for detecting the presence of viruses in small and bulk parenteral solutions. Both small and large volumes of Sodium Chloride Injection U.S.P. and 5 percent Dextrose Injection U.S.P. were inoculated with 100 I.U . or 1 I.U. of Tobacco Mosaic Virus (TMV) per ml of solution . The contents of these parenterals were concentrated to a retentate volume using molecular filtration . The retentate volume was examined for viral content using transmission electron microscopy with negative staining techniques. Efficacy was determined by comparison of the results of the contaminated controls with the contaminated test groups . Statistically significant differences were observed between the control groups, which were not subjected to the test method, and the test groups for both small and large volume parenteral solutions. Efficiency, which denotes the viral contamination level at which viruses are detectable, was determined by comparing the control groups of uncontaminated parenteral solutions with contaminated test groups of the same solutions . Both groups were subjected to the test methodology. The control and the test groups showed statistically significant differences at the 100 and the 1 I.U. TMV contamination levels. The results showed that the defined method of viral detection is efficacious and efficient at the tested TMV contamination levels . This method could probably be applied to the detection of other viral contaminants of parenteral solutions as well as to biological viral analysis methods.

Two substituted analogs of 3-amino-2,2-dimethyltetralin, namely 3-dimethylamino-7-hydroxy-2,2-dimethyl-1-tetralone HBr (J) and 3-dimethylamino-7-hydroxy-2,2-dimethyl-1-tetralol (MRSAL) were evaluated for opioid agonist and antagonist activity using the electrically-stimulated guinea pig ileum longitudinal muscle and mouse vas deferens preparations. The effects of these compounds in these tissues were compared to those induced by several opioid prototype agonists at mu, kappa and delta sites (normorphine, dihydromorphine, ethylketocyclazocine, U-50,488H, beta -endorphin, dynorphin 1-13, leu-enkephalin and DADLE) and one opioid antagonist (naloxone). The results of these experiments demonstrated that compound J inhibited contractions in a concentration-dependent manner as an opioid agonist and its effects were antagonized by naloxone in both preparations. The agonist effects of J were also irreversibly antagonized by beta -funaltrexamine pretreatment suggesting a preference for mu receptors. On the other hand, MRSAL was able to antagonize all the opioid agonist prototypes in a concentration-dependent manner, but with varying affinities. The differential opioid receptor selectivity for compound J was studied based on: (i) its agonist potency in guinea pig ileum longitudinal muscle versus the mouse vas deferens; (ii) its irreversible antagonism by beta -funaltrexamine in guinea pig ileum; and (iii) by the calculation of the apparent dissociation constant (Ke) of naloxone for this agonist in both preparations. The opioid receptor preference for MRSAL was based on its potency in antagonizing the opioid agonist prototypes by calculating its Ke value. Based on these criteria, compound J behaved as a mu receptor agonist while MRSAL had preference for mu rather than kappa or delta receptors.

The purpose of this study was to analyze how senior instructors in physical therapist educational programs in northern California define and seek to impart to students information about professional behavior. Towards this end a qualitative investigation was conducted using case study methodologies. The researcher conducted interviews with 8 instructors teaching in 4 physical therapist educational programs in northern California. Each interview was analyzed as an individual case study, followed by a cross case analysis to identify common themes. From this analysis nine common themes emerged: (1) instructors found it difficult to broadly define professional behavior. (2) instructors expect students to be on time. (3) instructors expect students to speak and act with courtesy and respect. (4) instructors expect students to communicate appropriately. (5) instructors expect students to dress appropriately. (6) instructors expect students to participate in class. (7) instructors consciously model professional behavior as a way to communicate their expectations. (8) Instructors give instructions and provide students with feedback about professional behavior. (9) instructors do not attach a specific grade to professional behavior. Instructor perceptions that professional behavior was difficult to define was consistent with existing literature, as was their reluctance to grade professional behavior. Behavioral expectations that emerged as themes in this study fit within existing descriptions of professional behavior for physical therapists, specifically the core values adopted by the American Physical Therapy Association. This relationship suggests that the core values document may be used as a framework through which classroom professional behavior can be viewed. Instructor perceptions of strategies for conveying information about professional behavior to students were consistent with existing literature on modeling and explicit teaching. Based on the results of this study, a five-step process is proposed to facilitate appropriate professional behaviors by students in the classroom: (1) define program expectations for professional behavior. (2) move from theory to practice. (3) intentionally and consistently model desired behavior. (4) provide immediate feedback and incremental consequences. (5) consciously plan for faculty interaction.

Tinnitus is experienced by as many as 50 million Americans and is clinically significant for approximately 12 million Americans. Tinnitus is often chronic and can evoke or exacerbate numerous psychological problems. No cure is available for tinnitus, thus treatment must focus on helping people learn to cope with tinnitus and its associated problems. The present study examined the efficacy of biodesensitization, biofeedback-controlled systematic desensitization, to decrease perceived tinnitus handicap, anxiety, depression, sleep difficulty, and daily assessments of distress in participants with tinnitus using a multiple-baseline design across 3 participants. The Tinnitus Handicap Inventory, Beck Depression Inventory, and Spielberger State-Trait Anxiety Inventory were administered at baseline and follow-up to determine changes in perceived handicap, depression, and anxiety. Also, the Tinnitus Monitoring Scale and Sleep Assessment Inventory were used to measure daily changes in tinnitus perception. It was hypothesized that biodesensitization therapy would produce significant decreases in participants' perceived tinnitus handicap, depression, and anxiety. It was also hypothesized that biodesensitization would yield improvements in daily and nightly tinnitus assessments. Results suggest that biodesensitization therapy related with decreases in scores on the Tinnitus Handicap Inventory and on Spielberger State-Trait Anxiety Inventory. No substantial change was observed on the Beck Depression Inventory. Results also showed a relationship between biodesensitization therapy and improvements in daily assessments of tinnitus and sleep for all participants. Findings are interpreted and future research is suggested.