Equipping providers to offer novel MPTs: Developing counseling messages for the Dual Prevention Pill in clinical studies and beyond

Introduction

The pipeline for multi-purpose prevention technologies includes products that simultaneously prevent HIV, pregnancy and/or other sexually transmitted infections. Among these, the Dual Prevention Pill (DPP) is a daily pill co-formulating oral pre-exposure prophylaxis (PrEP), and combined oral contraception (COC). Clinical cross-over acceptability studies for the DPP require training providers to counsel on a combined product. From February 2021-April 2022, a working group of eight HIV and FP experts with clinical and implementation expertise developed counseling recommendations for the DPP based on existing PrEP/COC guidance.

Assessment of policy/guidelines options and implications

The working group conducted a mapping of counseling messages from COC and oral PrEP guidance and provider training materials. Six topics were prioritized: uptake, missed pills, side effects, discontinuation and switching, drug interactions and monitoring. Additional evidence and experts were consulted to answer outstanding questions and counseling recommendations for the DPP were developed. Missed pills was the topic with the most complexity, raising questions about whether women could "double up" on missed pills or skip the last week of the pack to recover protection faster. Uptake required aligning the time to reach protective levels for both DPP components and explaining the need to take DPP pills during week 4 of the pack. The potential intensity of DPP side effects, given the combination of oral PrEP with COC, was an important consideration. Discontinuation and switching looked at managing risk of HIV and unintended pregnancy when stopping or switching from the DPP. Guidance on drug interactions contended with differing contraindications for COC and PrEP. Monitoring required balancing clinical requirements with potential user burden.

Actionable recommendations

The working group developed counseling recommendations for the DPP to be tested in clinical acceptability studies. Uptake: Take one pill every day for the DPP until the pack is empty. Days 1-21 contain COC and oral PrEP. Days 22-28 do not contain COC to allow for monthly bleeding, but do contain oral PrEP and pills should be taken to maintain HIV protection. Take the DPP for 7 consecutive days to reach protective levels against pregnancy and HIV. Missed pills: If you miss 1 pill multiple times in a month or 2+ consecutive pills, take the DPP as soon as you remember. Do not take more than 2 pills in a day. If 2+ consecutive pills are missed, only take the last missed pill and discard the other missed pills. Side effects: You may experience side effects when you start using the DPP, including changes to monthly bleeding. Side effects are typically mild and go away without treatment. Discontinuation/switching: If you decide to discontinue use of the DPP, but want to be protected from HIV and/or unintended pregnancy, in most cases, you can begin using PrEP or another contraceptive method right away. Drug interactions: There are no drug-drug interactions from combining oral PrEP and COC in the DPP. Certain medications are not recommended due to their contraindication with oral PrEP or COC. Monitoring: You will need to get an HIV test prior to initiating or restarting the DPP, and every 3 months during DPP use. Your provider may recommend other screening or testing.

Discussion

Developing recommendations for the DPP as a novel MPT posed unique challenges, with implications for efficacy, cost, and user and provider comprehension and burden. Incorporating counseling recommendations into clinical cross-over acceptability studies allows for real-time feedback from providers and users. Supporting women with information to use the DPP correctly and confidently is critically important for eventual scale and commercialization.

Barriers and Enablers Influencing Women's Adoption and Continuation of Vaginally Inserted Contraceptive Methods: A Literature Review

Most vaginally inserted methods have limited availability and use despite offering characteristics that align with many women's stated preferences (e.g., nonhormonal and/or on demand). The objective of this review was to identify enablers and barriers to women's adoption and continuation of vaginally inserted contraceptive methods in low- and middle-income countries (LMICs). We searched three databases (PubMed, Embase, and Web of Science) and 18 websites using keywords related to five vaginally inserted contraceptive methods (diaphragm, vaginal ring, female condom, copper intrauterine device [IUD], hormonal IUD) and terms associated with their adoption and continuation. Searches were limited to resources published between January 2010 and September 2020. Studies eligible for inclusion in our review presented results on women's use and perspectives on the enablers and barriers to adoption and continuation of the vaginally inserted contraceptive methods of interest in LMICs. Relevant studies among women's partners were also included, but not those of providers or other stakeholders. Data were coded, analyzed, and disaggregated according to a framework grounded in family planning (FP) literature and behavioral theories common to FP research and program implementation. Our initial search yielded 13,848 results, with 182 studies ultimately included in the analysis. Across methods, we found common enablers for method adoption, including quality contraceptive counseling as well as alignment between a woman's preferences and a method's duration of use and side effect profile. Common barriers included a lack of familiarity with the methods and product cost. Notably, vaginal insertion was not a major barrier to adoption in the literature reviewed. Vaginally inserted methods of contraception have the potential to fill a gap in method offerings and expand choice. Programmatic actions should address key barriers and enable voluntary use.

Gender-specific HIV and substance abuse prevention strategies for South African men: study protocol for a randomized controlled trial

BACKGROUND

Young men in South Africa face concurrent epidemics of HIV, drug and alcohol abuse, and unemployment. Standard HIV prevention programs, located in healthcare settings and/or using counseling models, fail to engage men. Soccer and vocational training are examined as contexts to deliver male-specific, HIV prevention programs.

METHODS

Young men (n = 1200) are randomly assigned by neighborhood to one of three conditions: 1) soccer league (n = 400; eight neighborhoods); 2) soccer league plus vocational training (n = 400; eight neighborhoods); or 3) a control condition (n = 400; eight neighborhoods). Soccer practices and games occur three times per week and vocational training is delivered by Silulo Ulutho Technologies and Zenzele Training and Development. At baseline, 6 months, 12 months, and 24 months, the relative efficacy of these strategies to increase the number of significant outcomes (NSO) among 15 outcomes which occur (1) or not (0) are summed and compared using binomial logistic regressions. The summary primary outcome reflects recent HIV testing, substance abuse, employment, sexual risk, violence, arrests, and mental health status.

DISCUSSION

The failure of men to utilize HIV prevention programs highlights the need for gender-specific intervention strategies. However, men in groups can provoke and encourage greater risk-taking among themselves. The current protocol evaluates a male-specific strategy to influence men's risk for HIV, as well as to improve their ability to contribute to family income and daily routines. Both interventions are expected to significantly benefit men compared with the control condition.

TRIAL REGISTRATION

ClinicalTrials.gov registration, NCT02358226 . Registered 24 November 2014.

Replicating Evidence-Based Practices with Flexibility for Perinatal Home Visiting by Paraprofessionals

Introduction Strategies are needed to improve the efficacy of paraprofessional home visitors for pregnant women in the United States. This study evaluates the maternal and child outcomes when evidence-based practices (EBP) are replicated with flexibility, rather than fidelity to a manualized intervention. Methods Pregnant mothers (N = 203) in five clinics were recruited in the waiting rooms and randomized to standard clinic care as the control condition (n = 104) or standard care plus home visiting (n = 99). Home visitors (n = 9) were selected, trained in foundational skills common to EBP and four problem domains (weight control, breastfeeding, daily habits, and depression). Independent interviewers assessed targeted outcomes at birth (82%) and 6 months later (83%).

RESULTS

Home visitors, called Mentor Mothers [MM], made an average of 14.9 home visits or telephone contacts (SD = 9; total contacts = 1491) addressing maternal daily habits, breastfeeding, and depression. Intervention and control mothers were similar in weight, Body Mass Index (BMI), depression and social support at baseline and 6 months later. The percentage of low birth weight babies was similar; intervention infants' growth (weight/height Z score) tended to be significantly better compared to the control condition.

DISCUSSION

There are many explanations for the failure to find significant benefits: insufficient statistical power; the benefits of repeated assessments by warm, supportive peers to improve outcomes; or the failure of EBP and the need to maintain replication with fidelity. All study mothers had better outcomes than documented among comparable published samples of low-income, Latina and Korean-American mothers in Los Angeles, CA. ClinicalTrials.gov registration NCT01687634.

Adjustment of a Population of South African Children of Mothers Living With/and Without HIV Through Three Years Post-Birth

Mothers living with HIV (MLH) and their children are typically studied to ensure that perinatal HIV transmission is blocked. Yet, HIV impacts MLH and their children lifelong. We examine child outcomes from pregnancy to 3 years post-birth among a peri-urban population of pregnant MLH and mothers without HIV (MWOH). Almost all pregnant women in 12 neighborhoods (98 %; N = 584) in Cape Town, South Africa were recruited and repeatedly assessed within 2 weeks of birth (92 %), at 6 months (88 %), 18 months (84 %), and 3 years post-birth (86 %). There were 186 MLH and 398 MWOH. Controlling for neighborhood and repeated measures, child and maternal outcomes were contrasted over time using longitudinal random effects regression analyses. For measures collected only at 3 years, outcomes were analyzed using multiple regressions. Compared to MWOH, MLH had less income, more informal housing and food insecurity, used alcohol more often during pregnancy, and were more depressed during pregnancy and over time. Only 4.8 % of MLH's children were seropositive; seropositive children were excluded from additional analyses. Children of MLH tended to have significantly lower weights (p < .10) over time (i.e., lower weight-for-age Z-scores) and were also hospitalized significantly more often than children of MWOH (p < .01). Children of MLH and MWOH died at similar rates (8.5 %) and were similar in social and behavioral adjustment, vocabulary, and executive functioning at 3 years post-birth. Despite living in households with fewer resources and having more depressed mothers, only the physical health of children of MLH is compromised, compared to children of MWOH. In township neighborhoods with extreme poverty, social, behavioral, language, and cognitive functioning appear similar over the first three years of life between children of MLH and MWOH.

Perceived mHealth barriers and benefits for home-based HIV testing and counseling and other care: Qualitative findings from health officials, community health workers, and persons living with HIV in South Africa

mHealth has been proposed to address inefficiencies in the current South African healthcare system, including home-based HIV testing and counseling (HTC) programs. Yet wide-scale adoption of mHealth has not occurred. Even as infrastructure barriers decrease, a need to better understand perceived adoption barriers by stakeholders remains. We conducted focus group discussions (FGD) in South Africa in 2016 with 10 home-based HTC field staff, 12 community health workers (CHWs) and 10 persons living with HIV (PLH). Key informant (KI) interviews were conducted with five health officials. Perceptions about current home-based HTC practices, future mHealth systems and the use of biometrics for patient identification were discussed, recorded and transcribed for qualitative analysis. Themes were based on a conceptual model for perceived mHealth service quality. Stakeholders brought up a lack of communication in sharing patient health information between clinics, between clinics and CHWs, and between clinics and patients as major barriers to care that mHealth can address. CHWs need better patient information from clinics in terms of physical location and health status to plan visitation routes and address patient needs. CHWs perceive that communication barriers create distrust towards them by clinic staff. PLH want automated appointment and medication reminders. KI see mHealth as a way to improve health information transfer to government officials to better allocate healthcare resources. Stakeholders are also optimistic about the ability for biometrics to improve patient identification but disagreed as to which biometrics would be acceptable, especially in older patients. All stakeholders provided useful information towards the development of mHealth systems. Hospitals are adopting patient-centered approaches that solicit feedback from patients and incorporate them into decision-making processes. A similar approach is needed in the development of mHealth systems. Further, such systems are critical to the successful extension of the health system from health facilities into people's homes.

Phytoestrogens Induce Differential Estrogen Receptor Alpha- or Beta-Mediated Responses in Transfected Breast Cancer Cells

Increased intake of phytoestrogens may be associated with a lower risk of cancer in the breast and several other sites, although there is controversy surrounding this activity. One of the mechanisms proposed to explain the activity of phytoestrogens is their ability to bind and activate human estrogen receptor a (ERα) and human estrogen receptor β (ERβ). Nine phytoestrogens were tested for their ability to transactivate ERα or ERβ at a range of doses. Mammary adenocarcinoma (MCF-7) cells were co-transfected with either ERα or ERβ, and an estrogen-response element was linked to a luciferase reporter gene. Dose-dependent responses were compared with the endogenous ligand 17β-estradiol. Purified genistein, daidzein, apigenin, and coumestrol showed differential and robust transactivation of ERα- and ERβ-induced transcription, with an up to 100-fold stronger activation of ERβ. Equol, naringenin, and kaempferol were weaker agonists. When activity was evaluated against a background of 0.5 nM 17β-estradiol, the addition of genistein, daidzein, and resveratrol superstimulated the system, while kaempferol and quercetin were antagonists at the highest doses. This transfection assay provides an excellent model to evaluate the activation of ERα and ERβ by different phytoestrogens in a breast cancer context and can be used as a screening bioassay tool to evaluate the estrogenic activity of extracts of herbs and foods.

Effects of cyclo (his-pro) plus zinc on glucose metabolism in genetically diabetic obese mice

AIMS

The specific objective of this study was to determine acute and long-term effects of cyclo (his-pro) (CHP) plus zinc and l-histidine (CZH) treatment on glucose metabolism in genetically obese (ob/ob), type 2 diabetic mice.

METHODS

Acute effects of 0.3 mg of CHP plus 10 mg of zinc and 0.5 mg of l-histidine/kg body weight (BW) on fed blood glucose concentrations and 3-h average of above fasting blood glucose concentrations (TAFGCs), an index of oral glucose tolerance test, in lean and ob/ob mice were determined. To evaluate long-term effects of CZH on TAFGCs, lean and ob/ob mice were treated with drinking water containing increasing doses of CHP (0, 0.5, 1.0 or 1.5 mg/l) plus 10 mg zinc and 0.5 mg of l-histidine/l for 3 weeks. During the treatment period, fed blood glucose concentrations, BW and food and water intake were determined. At the end of the treatment, fasting blood glucose concentrations, TAFGC and fed plasma insulin concentrations were determined.

RESULTS

Blood glucose concentrations significantly decreased when CZH was administered acutely via gastric gavage in food-deprived ob/ob mice. Similarly, 1.0 mg/l CHP treatment of mice with fixed amounts of 10 mg zinc and 0.5 mg l-histidine/l was optimal to decrease fed blood glucose and plasma insulin concentrations during a 3-week treatment period in ob/ob mice. TAFGC values in these mice also improved most significantly with the same combination of CHP, zinc and l-histidine used to test for fed blood glucose and plasma insulin levels. Fasting blood glucose concentrations and BW gains also decreased in ob/ob mice treated with 1.0 mg of CHP/l plus the same amount of zinc and l-histidine used in the above experiments. No effects of CZH treatment in lean mice were observed.

CONCLUSIONS

CZH is effective in decreasing blood glucose concentrations in genetically obese (ob/ob), type 2 diabetic mice. These data support our working hypothesis that CZH may be an important anti-hyperglycaemic agent.

Control of foot and mouth disease: lessons from the experience of the outbreak in Great Britain in 2001

An epidemic of foot and mouth disease occurred on an unprecedented scale in Great Britain in 2001. This was characterised by widespread dissemination of disease in sheep due to infection being present but unreported for at least three weeks before the first case was identified. As envisaged by the contingency plans, existing procedures dealt rapidly with disease in many parts of the country where outbreaks were reported. Elsewhere, the scale and speed of disease spread was so great that veterinary resources had to be supplemented on the operational front by a large influx of military and administrative support. At the time of writing (June 2002), the United Kingdom Government has already identified a number of key lessons, and will learn further from this experience and from the findings of inquiries, how a future outbreak of this unprecedented nature and extent could be handled. Lessons identified so far relate to the improvement of contingency plans, the wider impact on rural businesses and communities, reassessing the possible use of emergency vaccination, the availability of serological capacity, better animal identification and movement controls, carcass disposal, communications, data handling and management information. The authors present the initial lessons learned and which formed the basis of official submissions to the inquiries. Further lessons will be learned from the findings of those inquiries.

Stimulation of amylase release by Orexin is mediated by Orexin 2 receptor in AR42J cells

INTRODUCTION AND AIMS

Orexins have been demonstrated to have mainly central physiological functions, including regulation of food and water intake, sleep, and arousal. However, little is known about their direct peripheral effects, if any. As a first step toward understanding the role of Orexin in non-neuronal tissues or cells, we initiated studies to examine expression of Orexin receptors (OXR) in an established pancreatic tumor cell line AR42J. Secondly, we wanted to determine whether Orexins, in various molecular forms, are active to stimulate any known pancreatic cell functions in AR42J cells.

METHODOLOGY

Reverse transcription-PCR analysis was performed to identify the presence of specific Orexin receptor subtypes. Intracellular calcium mobilization and cAMP levels were measured following stimulation by Orexin A and B peptides, their respective C-terminal decapeptide fragments, and hypocretin-2-gly (glycine-extended Orexin B). Release of alpha-amylase was measured in conditioned media after acute stimulation with the set of Orexin peptides for 30 minutes. Cell proliferation was determined by H-thymidine incorporation after 24 hours following treatment with Orexins under serum-free condition.

RESULTS

RT-PCR and sequencing results showed that Orexin receptor subtype 2 (OX2R) was the main form expressed in AR42J cells. Orexins stimulated dose-dependent increases in intracellular calcium mobilization with EC50 0.05 nM for Orexin A and 0.1 nM for Orexin B but were unable to stimulate any significant cAMP accumulation or DNA synthesis even at micromolar concentrations. Both Orexin-A and -B, but not hypocretin-2-gly, also stimulated dose-dependent increases in amylase release in the AR42J cells. Orexin-A and -B carboxyl-terminal decapeptides elicited significant but much lower calcium and amylase responses.

CONCLUSION

Our data demonstrate that OX2R mediates Ca -dependent amylase release in AR42J cells, suggesting that Orexins may have secretory functions in pancreatic tumor cells.

Is NASH underdiagnosed among African Americans?

OBJECTIVE

Obesity and type 2 diabetes mellitus are considered risk factors for nonalcoholic steatohepatitis (NASH) and cryptogenic cirrhosis. Because obesity and type 2 diabetes are prevalent among African American females by the 5th and 6th decades, one would expect an increased number of African Americans among patients with NASH and cryptogenic cirrhosis.

METHODS

We determined the percentage of patients of African American and European American descent among all of the patients in our liver disease registry and those with NASH and cryptogenic cirrhosis. We also assessed the ethnicity of patients in our registry with other common liver diseases including hepatitis C, and we determined the ethnicity of patients seen at our center with type 2 diabetes and a primary diagnosis of obesity over a 4-yr period. Using census data, we compared these results to our local and regional ethnic demographics.

RESULTS

Overall, 199 of 2,253 patients (9%) in the registry were of African American descent, whereas 1,906 were of European American descent (85%). This distribution is similar to the ethnic mix in central Virginia (12% African American, 86% European American) and Albemarle County (12% African American, 83% European American). The prevalence of African American patients among individuals seen at our center for either type 2 diabetes or a primary diagnosis of obesity was over two times the prevalence of African Americans in the county or regional population. In contrast, of 159 NASH patients only one (0.6%) was of African American descent and 154 (97%) were of European American descent (p < 0.001 compared to the total registry, county, or region). Among 206 cryptogenic cirrhosis patients, only two (1%) were of African American descent, whereas 195 (95%) were of European American descent (p < 0.001 compared to the total registry). With regard to other liver diseases, African American patients were slightly overrepresented among hepatitis C patients and markedly overrepresented among patients with hepatic sarcoidosis, similar to previously reported national figures.

CONCLUSION

Although there is overrepresentation of African Americans among patients with major risk factors for NASH, individuals of primarily African American descent are infrequently represented among our patients with NASH or cryptogenic cirrhosis. This could result from underrecognition, underreferral, or a true lower prevalence of these disorders among African Americans.

Effects of arachidonic acid plus zinc on glucose disposal in genetically diabetic (ob/ob) mice

AIM

The present study is designed to determine whether arachidonic acid (AA) plus zinc improves clinical signs of diabetes in genetically diabetic ob/ob mice.

METHODS

In the first study, effects of acute administration of AA plus zinc on glucose disposal were determined in ob/ob and lean mice (n = 6 each). In the second study, ob/ob and lean mice were treated with increasing doses of AA plus zinc for 2 weeks (n = 5 each). Postprandial and fasting blood glucose concentrations, three-hour-area-average above fasting glucose concentration (TAFGC), water and food intake, body weight and plasma insulin concentrations were measured.

RESULTS

Acute administration of AA plus zinc significantly increased glucose disposal in ob/ob mice. In the second study, postprandial and fasting blood glucose concentrations, TAFGC, and water and food intake in ob/ob mice treated with AA plus zinc for 2 weeks were significantly decreased compared with those in mice given no AA. Plasma insulin concentrations in both lean and ob/ob mice were not changed by AA treatment in drinking water.

CONCLUSIONS

AA plus zinc in drinking water is effective in decreasing blood glucose levels in obese mice. These results indicate that use of these compounds should be considered as a dietary supplement to control hyperglycaemia in patients with type II diabetes.

Synergistic antidiabetic activities of zinc, cyclo (his-pro), and arachidonic acid

Previous studies have already shown that prostate extract (PE) has antidiabetic activity when given to animals and humans. In this study, we explore whether this antidiabetic activity is related to the high concentrations of zinc, cyclo (his-pro) (CHP), and the prostaglandin precursor, arachidonic acid (AA), in prostate tissue. When streptozotocin-induced diabetic rats were given drinking water containing 10 mg/L zinc and 100 mg/L PE for 3 weeks, fasting blood glucose levels and glucose clearance rates, but not plasma insulin levels, were significantly lower than at pretreatment. In subsequent experiments, blood glucose levels in rats given PE for 3 weeks were significantly lower than in rats given distilled water or 10 mg/L zinc alone. However, in rats given 100 mg/L CHP with zinc, blood glucose levels were also lower than in rats given PE alone. Time-course studies in diabetic rats given drinking water containing 20 mg/L Zn, 20 mg/L L-histidine, and 10 mg/L CHP showed that blood glucose levels dropped 209 +/- 53 mg/dL in 1 day and stayed low for 2 weeks. When CHP was replaced with 100 mg AA/L, blood glucose levels dropped 230 +/- 64 mg/dL in 5 days, but returned to the original values 11 days later. Growth rate improved and water consumption decreased significantly in CHP- and AA-treated diabetic rats. High intake of L-histidine and testosterone increased blood glucose concentrations in diabetic rats. To determine optimal dosages of CHP and AA, we gave rats drinking water containing 10 mg/L Zn and 0.5 mg/L L-histidine with various concentrations of CHP or AA. The most effective doses for reducing blood glucose levels were 0.32 mg CHP/kg/day and 11 mg AA/kg/day. These data suggest that the active antidiabetic ingredients in the PE are CHP, zinc, and AA or its precursors.

Laser ablation as a function of the primary absorber in dentin

BACKGROUND AND OBJECTIVE

Infrared transmission spectra of dentin reveal a broad absorption band between 6.0 and 7.0 microns composed of absorption peaks of water, collagen and carbonated hydroxyapatite. The nearly constant absorption and the existence of absorption peaks of different tissue components were used to investigate ablation as a function of the primary absorber.

STUDY DESIGN/MATERIALS AND METHODS

Laser ablation of dentin as a function of fluence was studied in the wavelength range between 6.0 and 7.5 microns using the Vanderbilt Free-Electron Laser (FEL). Depth and volume of the ablation crater were determined with a silicon replica method and subsequent confocal laser topometry. SEM investigations were performed on the irradiated surfaces. For the description of the experimental data an ablation model is developed.

RESULTS

At all applied wavelengths we found a linear increase of ablation depth as a function of fluence above a threshold fluence. The lower absorption of dentin at 7.5 microns compared to the absorption at 6.0, 6.5 and 7.0 microns results in a greater ablation threshold. At 6.0, 6.5 and 7.0 microns wavelengths the ablation thresholds are comparable. The experimental data are in good agreement with an ablation model using a mean absorption coefficient of the target material. No thermal cracking is observed after ablation in dentin. The post ablative surface structure at 6.0 and 7.0 microns looks similar whereas at 7.5 microns the surface reveals a greater roughness.

CONCLUSION

The ablation efficiency and threshold depend on the mean absorption but do not depend upon the chemical identity of the primary absorber in dentin. Calculations show that heat conduction during the laser pulse leads to a thermal equalization between the heated microstructures and surrounding tissue resulting in an ablation with little dependence on the primary absorber.

The Arabidopsis homolog of yeast TAP42 and mammalian alpha4 binds to the catalytic subunit of protein phosphatase 2A and is induced by chilling

Type 2A serine/threonine protein phosphatases (PP2A) have been implicated as important mediators of a number of plant growth and developmental processes. In an effort to identify plant PP2A substrates and/or regulators, we performed a yeast two-hybrid screen using an Arabidopsis PP2A catalytic subunit cDNA as bait. All true positives identified by this screen were derived from the same gene, which we have named TAP46 (2A phosphatase associated protein of 46 kD). The TAP46 gene appears to be a single-copy gene and is expressed in all Arabidopsis organs. Transcripts derived from this gene are induced by chilling treatment but not by heat or anaerobic stress. Immunoprecipitation assays using antibodies generated to a peptide spanning amino acids 356 to 366 of TAP46 indicate that TAP46 is associated with a type 2A protein phosphatase in vivo. A search of the database identified TAP46 as a homolog of Saccharomyces cerevisiae TAP42 and mammalian alpha4. These two proteins are known to bind to the catalytic subunit of PP2A and to function in the target-of-rapamycin signaling pathway. Our results identify TAP46 as a plant PP2A-associated protein, with a possible function in the chilling response, and suggest that a target-of-rapamycin-like signaling pathway may exist in plants.

Regulation of cholecystokinin-mediated amylase secretion by leptin in rat pancreatic acinar tumor cell line AR42J

Expression of the long form of the leptin receptor, the isoform that is considered to have full signaling capability, has been reported in the central nervous system and several peripheral cell types. However, only a few cell lines have been shown to express the long form of the receptor. AR42J, a cell line derived from azaserine-treated rat pancreas, is a common model for pancreatic acinar cell secretion. In this study, the presence of leptin-receptor variants and leptin action was evaluated in this cell line. Messenger RNAs for both the long and a short form of the leptin receptor were detected by reverse transcription-polymerase chain reaction (RT-PCR) in AR42J cells, and authenticity of the receptor was confirmed by DNA sequencing. Competitive binding studies demonstrated that binding of radiolabeled leptin was specific and did not cross-react with cholecystokinin (CCK). Biologic effects of leptin on amylase release and intracellular calcium mobilization were further assessed in the presence and the absence of CCK, a known pancreatic secretagogue. Although leptin alone (< or =200 ng/ml) did not affect basal amylase release, it inhibited amylase release stimulated by 1 nM CCK by 48%. Leptin alone had no significant effect on calcium mobilization. However, pretreatment of leptin (10 and 100 ng/ml) enhanced calcium responses stimulated by CCK. These data demonstrate that the rat pancreatic tumor cell line AR42J expresses a functional form of the leptin receptor that modulates the action of CCK in calcium mobilization and amylase release.

Hospital-based psychiatric experience before community-based practice for nurses: imperative or dispensable?

This article describes an Australian research project that explored the relevance of hospital-based experience in preparing psychiatric nurses for community-based practice. A qualitative design was selected to obtain in-depth information in an area in which no formal research has been undertaken. In-depth interviews were conducted with 6 psychiatric nurses currently engaged in community-based practice. The interviews were audiotaped, and the transcribed data were analyzed for major themes. The results indicated that the participants did not believe their hospital experience had prepared them to function effectively in the community. In some respects hospital experience was perceived as having hindered their transition into the community environment. This exploratory study indicates the need for further research and the exploration of alternative methods to prepare psychiatric nurses for community-based practice.

Eyelid resurfacing

BACKGROUND AND OBJECTIVE

Laser resurfacing of eyelids was examined in a series of experiments designed to measure beam parameters, surface temperatures, ablation characteristics, thermal damage, tissue responses and clinical outcomes. These data were collected for the purpose of developing a logical basis for clinical dosimetry.

STUDY DESIGN

All experiments were conducted with similar short-pulse CO(2) lasers (TruPulse, Albuquerque, NM) where the beam had been carefully characterized and calibrated. The chronological sequence examined begins with the photophysical laser/tissue interactions during the first few microsec of irradiation and ends with an evaluation of the efficacy of wrinkle reduction nine months after treatment.

RESULTS

Eyelid tissue removed by the first and second passes consisted mostly of epidermis with about 38 microm of thermal damage into the papillary dermis. Erythema resolved within four weeks and most patients experienced 70-100% wrinkle reduction by nine months.

CONCLUSION

A layer of contracted dermal scar tissue that replaced the thermally challenged zone in the dermis is identified as the substrate for wrinkle reduction. The data support the following dosimetry for periorbital wrinkle reduction: One pass 4-6 J/cm(2) (350-500 mJ into a 3 x 3 mm spot). A second treatment after 9-12 months may be more beneficial than a second pass.

The skills required for conducting a community psychiatric nursing assessment: a qualitative study

The shift in focus from primarily institutionally based care, to community-based care, has highlighted the need for community psychiatric nurses with appropriate skills to care for clients experiencing mental illness within the community. This paper describes the results of a qualitative research project undertaken to examine the skills required by psychiatric nurses in conducting an assessment within the community. In depth interviews were conducted with a sample of six currently practising community psychiatric nurses, with differing levels of experience. The findings identified the main skills as: interpersonal skills; psychiatric nursing knowledge base; the ability to work with a variety of treatment modalities; and, literacy skills. The specific significance of these skills for the educational preparation of community psychiatric nurses is discussed.

A rapid assay of endotoxin in whole blood using autologous neutrophil dependent chemiluminescence

A rapid (30 min) whole blood assay for the detection of lipopolysaccharide (LPS) is described. This chemiluminescent (CL) assay utilizes the CR1 and CR3 receptor-induced oxidant production of polymorphonuclear leucocytes as a detection platform. The differential priming of neutrophils in whole blood by LPS-antibody complexes allows the specificity of the assay to be achieved. Oxidant released in response to complement opsonized zymosan results in luminol oxidation and subsequent light emission. This is dependent on heat labile putative complement proteins in the plasma. The assay consists of a control which measures baseline whole blood neutrophil oxidant production. The test assay contains murine monoclonal IgM antibody against the Lipid A epitope of LPS and measures the enhanced chemiluminescent response of the neutrophils in the presence of LPS-antibody complexes. Maximal sensitivity of the CL assay is dependent upon optimal antigen-antibody equivalence and duration of pre-incubation with the whole blood sample. The quantification of LPS is possible by inclusion of a positive control containing a maximally reactive LPS dose (800 pg/ml Escherichia coli 055:B5 LPS at an antibody concentration of 0.8 microg/assay). The CL assay is insensitive to variations in patient neutrophil concentration over a minimum range of 0.5 to 20 x 10(9) cells/l. The CL assay is widely reactive with the LPS of many strains of gram negative bacteria but not with the cell wall products of gram positive bacteria or Candida and Aspergillus. In comparison to acid extraction chromogenic LAL, the CL assay demonstrates superior recovery precision and accuracy in in vitro studies. This was reproducible over a wide range of LPS concentrations (0.017-1.6 EU/ml or 20-2000 pg/ml). This assay may be a clinically useful tool for the diagnosis of infection or endotoxin in patients.

Multi-unit mapping of acoustic stimuli in gerbil inferior colliculus

Multi-unit peristimulus time (MU-PST) histograms were recorded in the gerbil inferior colliculus (IC) in response to tone burst stimuli. Histograms were collected every 100 microns as the recording electrode was advanced along the tonotopic axis of the central nucleus of the IC. Space/time maps of neural activity were constructed from these data. In most of our sample the pattern of response changed systematically as the stimulating frequency was increased in octave steps. At low frequencies (< 500 Hz) the pattern of response was broadly distributed spatially and phase-locked to the stimulus frequency. At higher frequencies (> 1 kHz) the pattern of response was more localized and showed no evidence of phase locking. The location of the maximum response to tones from 1 to 32 kHz moved ventrally along the tonotopic axis at an approximate rate of 230 microns/stimulus octave. The patterns of response were localized near stimulus threshold and spread over a larger region as level increased. This method of collecting and displaying multi-unit response maps provides an overview of ensemble activity that allows concurrent observation of spatial and temporal variations in activity patterns. The quantitative analysis of components of MU-PST Maps are consistent with trends illustrated with single-unit tuning and level functions. This perspective of IC activity suggests potential processing mechanisms that are congruent with single-unit reconstructions.

Differential expression of three Arabidopsis genes encoding the B' regulatory subunit of protein phosphatase 2A

Numerous plant processes ranging from signal transduction to metabolism appear to be mediated, in part, by type 2A protein serine/threonine phosphatases (PP2A). In an effort to identify factors that control the activity of this enzyme in plants, we have isolated and characterized DNA sequences encoding the B' regulatory subunit of PP2A from Arabidopsis thaliana. Specifically, we used PCR to amplify a segment of Arabidopsis cDNA that encodes a conserved section of the B' polypeptide. This PCR fragment was subsequently used as a probe to screen an Arabidopsis cDNA library and cDNA clones derived from three distinct genes were identified. The AtB' alpha and AtB' beta genes encode highly similar 57-kDa B' regulatory subunits while the third gene, AtB' gamma, encodes a more divergent 59-kDa B' protein. A comparison of the three Arabidopsis B' polypeptides to those of yeast and animals shows the core region of this protein to be the most conserved while the amino and carboxy termini vary both in length and sequence. Genomic Southern blots indicate that at most the Arabidopsis genome contains five genes encoding the B' regulatory subunit. The three genes identified in this study are expressed in all Arabidopsis organs, albeit at varying levels. In addition, mRNAs derived from the three genes accumulate differentially in response to heat shock. Our results indicate that the activity of plant PP2A might be regulated by a B' type regulatory subunit similar to those found in animals and yeast, and suggest possible roles for B'-containing PP2A complexes within plant cells.

Physician and plan effects on satisfaction of Medicaid managed care patients with their health care and providers

As many Medicaid patients move into managed care, it is important that physicians competing to serve these patients understand the factors that lead to patient satisfaction. This study uses survey data from 7,313 Oregon Medicaid managed care patients to create a model describing how provider effects and health plan effects relate to patients' satisfaction with their medical care and provider. Path analysis was used to test the explanatory power and strength of relationships in the model. Perceived technical and interpersonal physician quality and health plan rating were most strongly linked with these patients' satisfaction with their care and provider.

Selective impairment of the retrieval of people's names: a case of category specificity

Recent cases of 'proper names anomia' have been interpreted as arising from a category-specific recall deficit that is mediated either by the effects of 'uniqueness', or 'meaningfulness'. However, an alternative account is suggested by the report of a patient whose difficulties in naming familiar people arise from a selective learning impairment. The current case study presents data that are inconsistent with a learning interpretation of difficulties in naming people. We conclude that a dissociation exists between selective deficits affecting the learning and recall of people's names.

Effect of somatotropin treatment on lipogenesis, lipolysis, and related cellular mechanisms in adipose tissue of lactating cows

The effect of bST on the metabolism of lipid in adipose tissue was studied using tissue biopsies from lactating cows treated with bST for 8 d. Cows responded to treatment by increasing daily milk yield by 10.9 kg, although net energy intake was not changed. Thus, net energy balance was changed from highly positive to slightly negative (+7.7 to -1.1 Mcal/d). Consistent with these changes in net energy balance, lipogenesis rates were dramatically reduced (97%) in adipose tissue from bST-treated cows. Activities of acetyl-coenzyme A carboxylase (initial and total) and fatty acid synthase were also dramatically decreased. Therefore, for cows in positive energy balance, reduced lipid synthesis in adipose tissue represents a major mechanism whereby bST alters nutrient partitioning to support greater milk synthesis. Treatment with bST had no effect on beta-adrenergic-stimulated lipolysis in adipose tissue explants incubated in vitro with adenosine deaminase. However, bST treatment reduced the ability of adenosine to inhibit lipolysis in adipose tissue, which involved changes in both sensitivity and responsiveness to adenosine. Therefore, the enhanced lipolytic response to catecholamine in vivo with bST treatment relates to relief in the adenosine inhibitory signaling cascade rather than to a direct effect on the stimulatory signaling pathway.

I recognize your face but I can't remember your name: is it because names are unique?

Burton & Bruce (1992), and Cohen (1990a), offer alternative accounts of the differences in 'normal' and neurologically impaired subjects' abilities to recall people's names and other pieces of biographical information. Cohen claims that the principal difference between names and other biographical information is in their relative meaningfulness, while Burton & Bruce argue that uniqueness is the crucial variable. As yet existing empirical evidence cannot be explained within the framework of either of these accounts, although the Burton & Bruce (1992) proposal has the advantage of being implemented as an interactive activation model. This paper describes the case of a patient who, following a stroke, retained the ability to access 'unique' semantic information for familiar people she is no longer able to name. It is argued that this pattern of performance provides difficulties for the Burton & Bruce model. However, it can be accounted for by Cohen's account, and a modified version of Burton & Bruce's model (Bruce, Burton & Walker, 1994).

Family experiences when a child is HIV-positive: reports of natural and foster parents

The purpose of this exploratory study was to examine issues reported by natural and foster parents when caring for a child 3 years of age or younger with vertically transmitted HIV-disease. Issues common to both groups, and specific to the natural and foster parents were explored. The issues discussed by the natural mothers included guilt, their relationship with their infected child, and the effects of their HIV infection on their family. Issues discussed by foster mothers included their decision to foster a HIV-positive child, characteristics of their HIV- positive foster children, fears of transmission, and the effect of the HIV-positive foster child(ren) on their natural family. Issues common to both sets of mothers include disclosure, support, preparation for the HIV-positive child's death, and life in general. The experiences of these families are important to describe in order for pediatric nurses to give accurate, sensitive, and culturally appropriate care.

A hospital study of ice-making machines: their bacteriology, design, usage and upkeep

Ice-making machines have occasionally been implicated in nosocomial infection. We have examined the ice-making machines in our hospital both bacteriologically and for their general state of cleanliness and repair. Results were variable but, in most cases few organisms of significance were found. Some design features are considered and recommendations for the purchase, maintenance, cleaning and use of these machines are included.

Effect of in vivo somatotropin treatment of growing pigs on adipose tissue lipogenesis

The present study was undertaken to determine the effects of porcine somatotropin (pST) on glucose flux rates, lipogenic enzyme activities, and the abundance of fatty acid synthase mRNA in pig adipose tissue. Barrows were injected daily with 120 micrograms of pST/kg BW (n = 6) or excipient (n = 6). On d 11 of treatment, pigs were slaughtered (empty BW = 77 +/- 2 kg) and subcutaneous adipose tissue was collected. Basal incorporation of [14C]glucose into total lipid decreased by 86% with pST treatment, whereas glucose oxidation to CO2 decreased by 79%. Insulin (10 ng/mL) stimulated both glucose oxidation and incorporation into lipid by a small increment of similar magnitude for both treatment groups. Rates of lipogenesis determined in vitro were highly correlated with similar measurements made in vivo on the same set of animals (r = .76). The reduction in basal rates of lipogenesis corresponded to a 79% decrease in total (activated) acetyl-coenzyme A carboxylase activity and a 67% decrease in fatty acid synthase activity. Reduced nicotinamide adenine dinucleotide phosphate-generating enzymes were decreased to a lesser extent. Northern blot analysis of RNA from the same animals reveal a 90% decrease in mRNA for fatty acid synthase in the pST-treated group. The correlation between mRNA abundance and enzyme activity for fatty acid synthase was .90. These data indicate that the pST-induced reduction in adipose tissue lipid accretion in growing barrows is largely a result of diminished rates of lipogenesis that are manifestations of the decreased activities of the fatty acid-synthesizing enzymes. These changes seem to result from suppression of genes that encode for the lipogenic enzymes.

Effect of somatotropin on nonesterified fatty acid and glycerol metabolism in growing pigs

Eight crossbred barrows (71 kg initial BW) were allocated to two treatments involving daily i.m. injections of either excipient (control) or recombinantly derived porcine somatotropin (120 micrograms/kg of BW). On d 8 of treatment, beginning 15 h after injection, glycerol and nonesterified fatty acid (NEFA) kinetics were determined using a primed, continuous infusion of [2-3H]glycerol and [9,10(n)-3H]oleic acid. Kinetics were examined under both basal conditions and during a hyperinsulinemic/euglycemic clamp. Plasma concentrations of NEFA and glycerol and their respective entry rates were highly correlated. Insulin had no effect on plasma glycerol or glycerol entry rate, probably due to the very low rates that were observed in both the control and somatotropin-treated pigs. However, both plasma NEFA and oleic acid entry rate were reduced during hyperinsulinemia. Although indices of fat mobilization tended to be higher in pigs treated with somatotropin, the magnitude of the increases were small and would be sufficient to account for only a minor fraction of the decreased lipid accretion observed in somatotropin-treated pigs.

Effect of porcine somatotropin on in vivo glucose kinetics and lipogenesis in growing pigs

Crossbred barrows were used for in vivo studies investigating hormonal regulation of lipogenesis. The first experiment examined an in vivo method for determining rates of lipogenesis. Three barrows were infused with [U-14C]glucose and incorporation of radioactivity into triglycerides was determined in up to five biopsies of subcutaneous adipose tissue obtained over 7 h. Incorporation was linear after blood glucose specific radioactivity had reached a plateau and was constant over the entire infusion. For the second experiment, eight pigs (71 +/- 2.5 kg) were allocated to one of two treatments involving daily injections of excipient (control) or porcine somatotropin (pST; 120 micrograms/kg of BW). On d 10, beginning 15 h after injection, glucose incorporation into adipose tissue lipid was determined under both basal and hyperinsulinemic/euglycemic conditions. Basal glucose incorporation into lipid, particularly fatty acids, was markedly reduced (greater than 90%) during pST treatment. Although glucose incorporation was increased to a similar extent in both groups by hyperinsulinemia, the pST-treated pigs still exhibited markedly lower rates. Based on kinetic data, the decrease in lipid accretion of pST-treated pigs was primarily the result of a decrease in the rate of de novo synthesis. Furthermore, the reductions in glucose incorporation into fatty acids, glucose irreversible loss rate, and feed intake that occur with pST treatment were quantitatively similar.

Photodynamic therapy for corneal neovascularization

We have previously described corneal neovascularization (CNV) induced by the intrastromal injection of interleukin-2 (IL-2) in inbred mice. Photodynamic therapy (PDT), administered by a deeply penetrating 630 nm fiberoptic laser, can destroy neoplasms and their associated neovascularization with some selectivity, but can damage neighboring tissues when used for CNV. We performed PDT with a 514 nm ophthalmic argon laser in an attempt to induce regression of CNV and reduce the associated toxicity. Eight weeks following IL-2 injection, mice with CNV were injected i.v. with dihematoporphyrin ether (DHE). Seventy-two hours later, 11 eyes (group I) were irradiated with eight 800 mW, 1000 mu, 2 s spots. Controls included 11 vascularized corneas from mice that received DHE but no laser (group II), 11 that received laser but no DHE (group III), and 35 untreated vascularized corneas (group IV). Comparison of the mean areas of CNV in groups I through IV pretreatment (6.0, 6.5, 6.7, and 7.6 mm2) and 12 weeks posttreatment (4.3, 6.3, 5.6, and 7.5 mm2) revealed that a significant decrease was seen in group I only (p less than 0.04, ANOVA). Complications in group I included blepharitis (9%) and iris damage (18%). Histologic studies revealed no evidence of posterior segment damage. PDT with the 514 nm laser is safe and efficacious for the treatment of IL-2-induced CNV in this model.

Postnatal growth of cochlear spiral in Mongolian gerbil

Measurements were made of cochlear dimensions in an age-graded series of Mongolian gerbils. The radii of the cochlear spiral at five locations and the length of the modiolus were determined from in situ photographs of mid-modiolar sections. The anterior to posterior dimensions of the auditory bulla and of the inferior colliculus were also measured to provide a general context for inner ear growth functions. At birth in this species, the cochlear capsule is still growing, and, although the basal turn is closer to the final adult proportion than more apical turns, all radii approach adult dimensions together at 9-10 days after birth (DAB). Comparison of the morphological development of gerbil otic capsule with the change in cochlear tonotopic mapping observed during physiological development shows that growth is complete before the onset of measurable electrical responses at 12-14 DAB.

Photodynamic therapy in the treatment of squamous cell carcinoma of the head and neck

Photodynamic therapy is an experimental modality for tumor treatment based on the combined action of the tumor-localizing agent, ie, hematoporphyrin derivative, and red light. From 1985 through 1989, 26 patients were treated using hematoporphyrin-derived drugs and 630-nm light delivered by a tunable dye laser. All patients had biopsy-proved squamous cell carcinoma of the head and neck, and they had either failed the traditional treatment modalities or refused conventional therapies. Histological complete responses were achieved in 20 (77%) of 26 patients and partial responses in 5 (19%) of 26 patients for periods up to 48 months. Only minimal toxic reaction was noted in the group. As a guide to treatment planning for a patient group with large tumors, we used an optical dosimetry model based on tissue optics. The rate of complete responses to this treatment was 8 (73%) of 11. Our data indicate that photodynamic therapy is capable of inducing significant clinical and histological responses in the majority of those treated, and in some patients a prolonged response is produced. In certain select head and neck malignancies, photodynamic therapy has an important role as a treatment modality.

Prophylaxis against hepatitis A for travel

OBJECTIVE

To develop a rational practice policy for prophylaxis against hepatitis A for travellers to high risk areas.

DESIGN

18 Month prospective study of consecutive patients who requested prophylaxis against hepatitis A.

SETTING

Inner city general practice.

SUBJECTS

104 Patients aged 15-61 (mean 30) assessed for risk factors for hepatitis A and put into groups depending on predictions from the risk factors of their immunity.

MAIN OUTCOME MEASURES AND RESULTS

All patients were screened for antibody to hepatitis A virus. Of 52 patients with no risk factors 47 had no antibody and were thus susceptible to hepatitis A. All 27 patients with major risk factors (having been brought up in an endemic area or with a history of jaundice) were immune. Of 25 patients with minor risk factors (a history of previous travel in high risk areas, drug abuse, having lived in a squat or travelled rough, or having lived with someone who had jaundice) 12 were immune (p less than 0.001, chi 2 test).

CONCLUSIONS

All travellers requesting prophylaxis against hepatitis A should be assessed for risk factors for previous exposure to hepatitis A. Those with no risk factors could be immunised with human normal immunoglobulin without screening. The remainder should be tested for hepatitis A antibody and those found to be susceptible should be immunised.

Single-dose efficacy and safety of zindotrine, a new oral bronchodilator

Zindotrine, a new bronchodilator, may be an alternative to theophylline in treating reversible airflow obstruction. Efficacy and cardiovascular effects of a single 300 mg oral dose of zindotrine were compared with placebo in a two-period, double-blind, crossover trial. Twelve subjects with airflow obstruction reversible after isoproterenol and theophylline completed the trial. Improvement in pulmonary function (forced vital capacity [FVC], forced expiratory volume in one second, and forced expiratory flow rate from 25 to 75 percent of FVC) was greater after zindotrine than with placebo. Pulmonary function tests increased 15 percent or more over baseline in 30 minutes after active drug, lasting up to 6 hours. Mild decreases in heart rate and mean blood pressure occurred after both treatments, with changes equal in both treatment groups. Six subjects had mild subjective side effects after zindotrine (headache, dizziness, vertigo, flushing, and heartburn) compared with one report of lightheadedness after placebo. A single dose of zindotrine 300 mg provides effective bronchodilator action with a relatively prolonged response and tolerable side effects.

Autologous fibrin tissue adhesive: factors influencing bonding power

Bonding power of Autologous Fibrin Tissue Adhesive (AFTA) is directly related to its fibrinogen concentration. By increasing the ammonium sulfate concentration 100% during fibrinogen precipitation, the bonding power of two glued 1-cm2 pieces of human dura almost doubled. No relationship between blood fibrinogen level and bonding power was demonstrated. Comparing AFTA with Fibrin Sealant, the commercial fibrin tissue adhesive, shearing strength between two glued pieces of human dura with AFTA was less 10 minutes and greater 30 minutes after gluing. Gluing a TORP (Richards) to a 1-cm2 piece of human dura yielded generally somewhat greater bonding power when using Fibrin Sealant. Autologous Fibrin Tissue Adhesive provides bonding power adequate for middle-ear surgery, eliminates transmission of viral diseases and, unlike Fibrin Sealant, AFTA is available in the United States.

Propylene glycol-induced cholesteatoma in chinchilla middle ears

Propylene glycol is a solvent commonly used in topical otic preparations. This study examines the occurrence of inflammatory changes and cholesteatoma in chinchilla middle ears after the application of propylene glycol in varying concentrations. A total of 32 ears were studied, divided into four treatment groups. Three groups received propylene glycol in concentrations of 10%, 50%, and 90%. One group received normal saline. Six weeks after the application of propylene glycol to the middle ear through the bulla, examination revealed cholesteatoma, tympanic membrane perforations, and middle ear adhesions in most of the ears subjected to 50% and 90% propylene glycol. Only one ear treated with 10% propylene glycol showed a cholesteatoma, while the group treated with normal saline showed only mild inflammation. Histologic preparations confirmed cholesteatoma and revealed replacement of the normal columnar epithelium by keratinizing stratified squamous epithelium, inflammatory infiltration, and granulation tissue eroding underlying bone. We conclude that exposure to propylene glycol in high concentrations will consistently produce cholesteatoma in chinchilla middle ears. Although the effects of propylene glycol in the human middle ear are yet to be investigated, we recommend the avoidance of otic preparations containing high concentrations of propylene glycol in patients with tympanic membrane perforations.

Effects of caffeine and 3-isobutyl 1-methyl xanthine on caprine milk secretion

The objective of these studies was to determine if methyl xanthines can be used to alter milk production or composition in ruminants by enhancing adipose tissue mobilization. Three trials were conducted, one with intravenous caffeine infusions, one with intramuscular caffeine injections, and one with intramuscular injections of 3-isobutyl 1-methyl xanthine. Results indicate that: 1) continuous intravenous infusions of caffeine (720 mg/d) may reverse the milk fat depression of intravenously infused glucose in dairy goats; 2) intramuscular injections of caffeine (200 mg twice daily) do not reverse the milk fat-depressing effects of pelleted dairy goat diets during the 4th mo of lactation; and 3) intramuscular injections of 3-isobutyl 1-methyl xanthine (50 mg twice daily) do not consistently affect milk production of early lactation dairy goats.

Inflammatory effects of topical antibiotic suspensions containing propylene glycol in chinchilla middle ears

This study examines the occurrence of inflammatory changes and cholesteatoma in the middle ears of seven chinchillas after the application of topical antibiotic suspensions containing two different concentrations of propylene glycol. The preparations used were Cortisporin otic suspension, which contains neomycin, polymyxin B, hydrocortisone, and 10.5% propylene glycol, and Cortisporin ophthalmic suspension, containing the same ingredients, but only a 2% concentration of propylene glycol. Six weeks after the administration of the Cortisporin preparations, applied to the middle ear through a transbulla approach, no cholesteatomas were found in the seven ears treated with the ophthalmic suspension. Evidence of mild inflammation was present in only two of these ears. In the seven contralateral ears treated with the otic suspension, middle ear adhesions were found in six, cholesteatoma was present in four, serous effusions were found in three, and one had a large tympanic membrane perforation. The ears that showed cholesteatomas also had histologic evidence of squamous metaplasia, granulation tissue, and erosion of the underlying bone. We submit that the pathologic responses of the middle ear mucosa treated with the otic suspension, were due to an inflammatory response to the higher concentration of propylene glycol compared to that of the ophthalmic suspension.

Autologous fibrin tissue adhesive biodegration and systemic effects

A series of experiments was conducted to investigate the rate of Autologous Fibrin Tissue Adhesive (AFTA) degradation by the fibrinolysis inhibitor, epsilon amino caproic acid (EACA). The duration of AFTA clots in vitro, subcutaneous, and in the middle ear was prolonged for a time interval that was proportional to the concentration of EACA in Component II of the adhesive. No toxic reactions were observed in the middle or inner ear. Systemic pathology (thrombosis or emboli) could not be related to the presence of EACA applied in the middle ear or directly into the blood stream at concentrations (mg/kg body weight) up to 1,500 times that expected to occur during surgery on humans.