Examining gender differences in adolescent exposure to food and beverage marketing through go-along interviews

This study explores how adolescents engage with unhealthy food and beverage marketing in online settings, from a gender perspective. Employing an online ethnography approach and using go-along interviews, we explored the experiences of adolescent boys and girls aged 13-17 as they navigated their online experiences with digital food and beverage marketing. Notable themes emerged, including the identification of predatory actions by food companies, the role of protective factors such as family, and the influence of social media influencers in shaping adolescent dietary preferences. Importantly, this research unearthed gender disparities in the participants' responses. Girls, in particular, exhibited a heightened awareness of the protective role played by their families, emphasized the influence of color in marketing strategies, recognized the significance of gender in marketing, and reported exposure to alcohol advertisements-findings that boys less frequently echoed. The study underscores the importance of adolescence as a critical phase in development, during which food companies target these impressionable individuals, driven by their independence and potential for brand loyalty. Moreover, it highlights the potential avenue of gender-specific marketing, offering valuable insights into the gendered dimensions of adolescents' food marketing experiences. By examining the interplay between digital food marketing and gender, this research addresses a critical gap in the literature, shedding light on how gender influences adolescents' perceptions, responses, and behaviors in the context of food marketing strategies. These findings have the potential to inform adolescents of the marketing techniques that target them and guide policymakers in developing and implementing evidence-based regulations aimed at safeguarding adolescents from exposure to unhealthy food marketing.

Sensitivity to change of generic preference-based instruments (EQ-5D-3L, EQ-5D-5L, and HUI3) in the context of treatment for people with prescription-type opioid use disorder in Canada

PURPOSE

Using data from a randomized controlled trial for treatment of prescription-type opioid use disorder in Canada, this study examines sensitivity to change in three preference-based instruments [EQ-5D-3L, EQ-5D-5L, and the Health Utilities Index Mark 3 (HUI3)] and explores an oft-overlooked consideration when working with contemporaneous responses for similar questions-data quality.

METHODS

Analyses focused on the relative abilities of three instruments to capture change in health status. Distributional methods were used to categorize individuals as 'improved' or 'not improved' for eight anchors (seven clinical, one generic). Sensitivity to change was assessed using area under the ROC (receiver operating characteristics) curve (AUC) analysis and comparisons of mean change scores for three time periods. A 'strict' data quality criteria, defined a priori, was applied. Analyses were replicated using 'soft' and 'no' criteria.

RESULTS

Data from 160 individuals were used in the analysis; 30% had at least one data quality violation at baseline. Despite mean index scores being significantly lower for the HUI3 compared with EQ-5D instruments at each time point, the magnitudes of change scores were similar. No instrument demonstrated superior sensitivity to change. While six of the 10 highest AUC estimates were for the HUI3, 'moderate' classifications of discriminative ability were identified in 12 (of 22) analyses for each EQ-5D instrument, compared with eight for the HUI3.

CONCLUSION

Negligible differences were observed between the EQ-5D-3L, EQ-5D-5L, and HUI3 regarding the ability to measure change. The prevalence of data quality violations-which differed by ethnicity-requires further investigation.

Understanding the tool influence function during sub-aperture belt-on-wheel glass polishing

The tool influence function (TIF) during sub-aperture belt-on-wheel polishing has been evaluated as a function of various process conditions (belt use/wear, dwell time, displacement, belt velocity, and wheel modulus and diameter) on fused silica glass workpieces using C e O ₂ polishing media. TIF spots are circular or elliptical in shape with a largely flat bottom character. The volumetric removal rate varies significantly with belt use (or wear), stabilizing after ∼15m i n of use. A modified Preston model, where the pressure dependence is adjusted using a different scaling of the wheel modulus (E w0.5), largely predicts the volumetric removal rate over the range of process conditions evaluated. The relatively high volumetric removal rate of 30-60m m ³/h using a fixed C e O ₂-in-resin-host belt offers a rapid, and hence, more economical, initial polish of aspheric and freeform optics.

Human Immunodeficiency Virus transmission by HIV Risk Group and Along the HIV Care Continuum: A Contrast of 6 US Cities

BACKGROUND

Understanding the sources of HIV transmission provides a basis for prioritizing HIV prevention resources in specific geographic regions and populations. This study estimated the number, proportion, and rate of HIV transmissions attributable to individuals along the HIV care continuum within different HIV transmission risk groups in 6 US cities.

METHODS

We used a dynamic, compartmental HIV transmission model that draws on racial behavior-specific or ethnic behavior-specific and risk behavior-specific linkage to HIV care and use of HIV prevention services from local, state, and national surveillance sources. We estimated the rate and number of HIV transmissions attributable to individuals in the stage of acute undiagnosed HIV, nonacute undiagnosed HIV, HIV diagnosed but antiretroviral therapy (ART) naïve, off ART, and on ART, stratified by HIV transmission group for the 2019 calendar year.

RESULTS

Individuals with undiagnosed nonacute HIV infection accounted for the highest proportion of total transmissions in every city, ranging from 36.8% (26.7%-44.9%) in New York City to 64.9% (47.0%-71.6%) in Baltimore. Individuals who had discontinued ART contributed to the second highest percentage of total infections in 4 of 6 cities. Individuals with acute HIV had the highest transmission rate per 100 person-years, ranging from 76.4 (58.9-135.9) in Miami to 160.2 (85.7-302.8) in Baltimore.

CONCLUSION

These findings underline the importance of both early diagnosis and improved ART retention for ending the HIV epidemic in the United States. Differences in the sources of transmission across cities indicate that localized priority setting to effectively address diverse microepidemics at different stages of epidemic control is necessary.

Improving health equity and ending the HIV epidemic in the USA: a distributional cost-effectiveness analysis in six cities

BACKGROUND

In the USA, Black and Hispanic or Latinx individuals continue to be disproportionately affected by HIV. Applying a distributional cost-effectiveness framework, we estimated the cost-effectiveness and epidemiological impact of two combination implementation approaches to identify the approach that best meets the dual objectives of improving population health and reducing racial or ethnic health disparities.

METHODS

We adapted a dynamic, compartmental HIV transmission model to characterise HIV micro-epidemics in six US cities: Atlanta, Baltimore, Los Angeles, Miami, New York, and Seattle. We considered combinations of 16 evidence-based interventions to diagnose, treat, and prevent HIV transmission according to previously documented levels of scale-up. We then identified optimal combination strategies for each city, with the distribution of each intervention implemented according to existing service levels (proportional services approach) and the racial or ethnic distribution of new diagnoses (between Black, Hispanic or Latinx, and White or other ethnicity individuals; equity approach). We estimated total costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios of strategies implemented from 2020 to 2030 (health-care perspective; 20-year time horizon; 3% annual discount rate). We estimated three measures of health inequality (between-group variance, index of disparity, Theil index), incidence rate ratios, and rate differences for the selected strategies under each approach.

FINDINGS

In all cities, optimal combination strategies under the equity approach generated more QALYs than those with proportional services, ranging from a 3·1% increase (95% credible interval [CrI] 1·4-5·3) in New York to more than double (101·9% [75·4-134·6]) in Atlanta. Compared with proportional services, the equity approach delivered lower costs over 20 years in all cities except Los Angeles; cost reductions ranged from $22·9 million (95% CrI 5·3-55·7 million) in Seattle to $579·8 million (255·4-940·5 million) in Atlanta. The equity approach also reduced incidence disparities and health inequality measures in all cities except Los Angeles.

INTERPRETATION

Equity-focused HIV combination implementation strategies that reduce disparities for Black and Hispanic or Latinx individuals can significantly improve population health, reduce costs, and drive progress towards Ending the HIV Epidemic goals in the USA.

FUNDING

National Institute on Drug Abuse.

Inflammatory bowel disease and the gut microbiota

Inflammatory bowel disease (IBD) is a group of immune-mediated disorders characterised by a chronic, relapsing-remitting inflammation predominantly affecting the gastrointestinal tract. IBD is incurable, affecting people in their most productive years. IBD is historically seen as a disease of Westernised nations although in recent times other countries have seen an exponential rise in cases. Although the exact pathogenesis remains unclear, evidence suggests that microbiota changes play a critical role in IBD pathogenesis. Over the past two decades, IBD has become one of the most studied human conditions linked to the gut microbiota. However, deciphering the intricate link between the gut microbiota and therapeutic efficacy remains elusive. This review will summarise the current evidence relating to the gut microbiota and its involvement in IBD pathogenesis as well as the impact of IBD treatments including pharmaceutical-, nutraceutical- and microbial-focused regimens on the gut microbiota.

Empirical Validity of a Generic, Preference-Based Capability Wellbeing Instrument (ICECAP-A) in the Context of Spinal Cord Injury

BACKGROUND

Assessing the validity of generic instruments across different clinical contexts is an important area of methodological research in economic evaluation and outcomes measurement.

OBJECTIVE

Our objective was to examine the empirical validity of a generic, preference-based capability wellbeing instrument (ICECAP-A) in the context of spinal cord injury.

METHODS

This study consisted of a secondary analysis of data collected using an online cross-sectional survey. The survey included questions regarding demographics, injury classifications and characteristics, secondary health conditions, quality of life and wellbeing, and functioning in activities of daily living. Analysis comprised the descriptive assessment of Spearman's rank correlations between item-/dimension-level data for the ICECAP-A and four preference-based health-related quality of life (HRQoL) instruments, and discriminant and convergent validity approaches to examine 21 evidence-informed or theoretically derived constructs. Constructs were defined using participant and injury characteristics and responses to a range of health, wellbeing and functioning outcomes.

RESULTS

Three hundred sixty-four individuals completed the survey. Mean index score for the ICECAP-A was 0.761; 12 (3%) individuals reported full capability (upper anchor; score = 1), and there were no reports of zero capabilities (lower anchor; score = 0). The strongest correlations were dominated by items and dimensions on the comparator (HRQoL) instruments that are non-health aspects of quality of life, such as happiness and control over one's life (including self-care). Of 21 hypothesised constructs, 19 were confirmed in statistical tests, the exceptions being the exploratory hypotheses regarding education and age at injury.

CONCLUSION

The ICECAP-A is an empirically valid outcome measure for assessing capability wellbeing in people with spinal cord injury living in a community setting. The extent to which the ICECAP-A provides complementary information to preference-based HRQoL instruments is dependent on the comparator.

Healthy Eating Policy for a provincial health authority in Atlantic Canada

Issue

Poor diets, the global leading cause of death and disability, are influenced by individual and community factors. Community health care settings have the potential to shape dietary behavior through food and beverage environments, and a healthy eating culture that supports the healthier choice as the easier choice.

Description of the Problem

The Nova Scotia Health Authority (NSHA) is a provincial government health authority in Atlantic Canada, responsible for delivering services to nearly 1 million people in 10 hospitals, 8 ERs, and 135 community locations. The NSHA employs over 23,400 health workers. In 2015, the NSHA centralized its governance, merging 9 regional health districts into one. Policies and procedures were re-written with a provincial focus, including a new Healthy Eating Policy (HEP) adopted in 2018. In this paper, we discuss the implementation of the HEP as a case study for how healthy eating can be fostered through continuous quality improvement.

Results

The policy upholds NSHA as a community leader working collaboratively with internal and external partners. To be a credible leader in changing the landscape around healthy eating, NSHA agrees to “walk the talk” and model an evidence-based healthy eating policy. A hospital in Halifax piloted pricing, placement and promotion interventions to further support healthier eating. These have been expanded to other sites across NS.

Lessons

1) Internal Capacity Building - A Healthy Eating Steering Committee promotes healthy eating across the health system, including initiatives in partnership with auxiliaries, foundations and staff. 2) Improving Evaluation Infrastructure- The interventions led to strategic thinking of future point of sale systems and ways to improve data collection for evaluation 3) Academic Partnerships - NSHA and Dalhousie University formed a collaborative partnership to strengthen evaluation capacity making use of the latest evidence and methods from food environments research.

Key messages

The Nova Scotia Health Authority’s Health Eating Policy supports healthy eating across the province, and promotes supportive environments where the healthier choice is the easier choice. A hospital site in Halifax, NS, implemented a variety of pricing, placement and promotion interventions to promote a healthy workplace environment for employees and community members.

Transforming food retail for better health: The Healthy Stores 2020 trial

Background

How food is promoted in food retail settings impacts population diet. Foods high in sugar, fat and/or salt are promoted by retailers to attract impulse purchases. To combat the high burden of chronic disease and associated conditions confronting society we examined the impact of restricted retail merchandising (promotion and visibility) of discretionary food and beverages on sales and business outcomes.

Methods

We conducted a pragmatic randomised controlled trial in partnership with a retail organisation operating stores in remote communities of Australia (the Arnhem Land Progress Aboriginal Corporation). Twenty consenting stores were allocated to the 12-week intervention (7-point Healthy Stores 2020 strategy) or to usual retail practice. Four intervention stores with retail competition implemented a modified 6-point strategy. Weekly sales data were used to assess intervention impact on free sugars (g) to energy (MJ) (primary outcome) derived from all purchased food and beverages. Impact on gross profit and sales of targeted food and beverages was also assessed. Managers of intervention stores were interviewed to determine their views on customer response and impact on retail practice.

Results

Free sugars were reduced by a relative 2.8% (95% CI -4.8, -0.7). There were significant reductions in free sugars from targeted beverages (-6.4%; -11.1, -1.5) and soft drinks (-12.5%; -18.1, -6.5). Gross profit was not impacted adversely. Managers mostly viewed the strategy favourably and of benefit to the community.

Conclusions

The public health and business relevant gains demonstrated by this novel trial have resulted in ALPA converting their stores to the Healthy Stores 2020 strategy and integrating the strategy in to their nutrition policy. Retail competition impedes complete implementation of the 7-point strategy. Tackling this will require collective agreement by retailers to implement the full strategy and/or government policy power.

Key messages

Restricting merchandising of unhealthy foods can achieve both public health relevant and business relevant gains. Working in partnership with retailers is critical to testing real-world interventions to impact population diet.

Sustained correction of glycogen storage disease type II using adeno-associated virus serotype 1 vectors

Glycogen storage disease type II (GSDII) is caused by a lack of functional lysosomal acid alpha-glucosidase (GAA). Affected individuals store glycogen in lysosomes beginning during gestation, ultimately resulting in fatal hypertrophic cardiomyopathy and respiratory failure. We have assessed the utility of recombinant adeno-associated virus (rAAV) vectors to restore GAA activity in vivo in a mouse model of GSDII (Gaa(-/-)). A single systemic administration of a rAAV serotype 1 (rAAV1) vector to neonate animals resulted in restored cardiac GAA activity to 6.4 times the normal level (mean=641+/-190% of normal (Gaa(+/+)) levels with concomitant glycogen clearance) at 11 months postinjection. Greater than 20% of normal levels of GAA activity were also observed in the diaphragm and quadriceps muscles. Furthermore, functional correction of the soleus skeletal muscle was also observed compared to age-matched untreated Gaa(-/-) control animals. These results demonstrate that rAAV1 vectors can mediate sustained therapeutic levels of correction of both skeletal and cardiac muscles in a model of fatal cardiomyopathy and muscular dystrophy.

Mapping genes that regulate density of dopamine transporters and correlated behaviors in recombinant inbred mice

Binding of 3beta-(4-iodophenyl) tropane-2beta-carboxylic acid methyl ester ([125I]RTI-55) to the dopamine transporter (DAT) in neostriatum from C57BL/6J, DBA/2J, and 21 BXD recombinant inbred (RI) mouse strains indicated highly significant strain differences in DAT density (Bmax) but no significant differences in affinity (Kd) for this radioligand. Strain mean Bmax values and the known genomic locations of 1390 marker loci were used to carry out a genome-wide search for quantitative trait loci (QTLs), which are chromosomal sites containing genes that influence DAT expression. This search revealed an unusually large effect QTL on chromosome 19 in the region of the proopiomelanocortin pseudogene Pomc-ps1 (8-11 cM), homologous to regions of human chromosomes 9q21 and 11q12-13. This QTL (logarithm of the odds 4.7, df = 1, p = 3 x 10(-6)) by conservative estimates accounts for just over half of the genetic variation in DAT binding site density. The QTL is not the DAT gene itself (Dat1, chromosome 13), but a powerful modulator of DAT expression in neostriatum. Furthermore, DAT expression levels in 20 of the BXD RI strains and the chromosome 19 QTL were correlated with cocaine and methamphetamine-induced locomotor activation and thermic responses (hypo- or hyperthermia), but were not correlated with behaviors related to sensitization, reward, voluntary consumption, stereotypy, or seizures induced by these two psychostimulant drugs. The results suggest that there is a gene(s) on proximal chromosome 19 that strongly influences DAT expression in neostriatum and may influence psychostimulant-induced activity and thermal responses.

The effects of iron supplementation in preweaning piglets

The trial was carried out at a commercial pig farm in Bukit Pelanduk, Negeri Sembilan, Malaysia. The objective of the study was to assess the efficacy of supplemental iron in drinking water and iron in paste form in comparison with the iron dextran injection. A total of 12 litters were used divided into three treatments : iron dextran injection (ID), Fedexx" - iron in paste form (IP) and Opti-iron" - iron in drinking water (IW). Hemoglobin level and growth performance parameters were monitored weekly over a period of 28 days. ID piglets had significantly higher (p < 0.05) body weight and weekly weight gain compared with IW piglets at 21 and 28 days of age whereas no significant different (p > 0.05) results were found between IP and IW piglets. Hemoglobin level from days 0 to 28 showed statistical difference (p > 0.05) between piglets in IP and IW groups. Mild anemia was found in IP piglets but not for ID and IW piglets compared with normal value (> 9 g/dL). Hemoglobin (Hb) levels were positively correlated (p < 0.05, r = .47) with body weight at 28 days of age. In conclusion, pigs supplemented with iron in paste form and drinking water had poorer growth performance than iron dextran injection piglets. Piglets given iron in paste form had mild anemia. It is advisable to give multiple doses of oral iron to piglets in order to prevent iron deficiency anemia. During the first 4 weeks of life, the body weights of the piglets increased by up to 5-fold. The dietary requirement for iron during this period is 7 mg per day but only 1 mg per day can be supplied by the sow's milk (Cunha, 1977; Miller and Ullrey, 1997; Roberts, 1998). The need to provide the piglets with an adequate amount of iron before weaning is therefore imperative because sow's milk alone will not meet the iron requirements of rapid growth and expanding blood volume (Hannan, 1971). Several different methods can be used to offer iron to preweaning piglets. The most common administration method for iron in piglets is through an intramuscular injection of iron dextran complex at 3 days of age. A single dose of 200 mg/ml iron-dextran is effective against iron deficiency anemia. However, the method is very stressful to the piglets. They will suffer more pain if a greater dosage of iron is given intramuscularly. Furthermore, poor iron injection techniques may cause considerable trauma to the muscles, staining of hams or create abscesses and lead to downgrading of the carcasses (Roberts, 1998). Since there are several drawbacks to the iron injection, alternative methods need to be considered in intensive farming i.e. supply iron orally (Miller and Ullrey, 1997). The oral administration of iron has two advantages: cost and the fact that absorption is regulated by the intestinal mucosae. However, oral administration requires multiple doses. This is because a single dose may not be sufficient to protect the piglets from iron deficiency anemia for the first 4 weeks post-partum. The iron bioavailability in oral iron depends greatly on iron status of animals (Amine et al., 1972; Susan and Wright, 1985). In addition, dietary factors such as amino acids and protein sources (Martinez et al., 1981), pectin content, phytate (Morris and Ellis, 1982) and the other minerals (Elvehjem and Hart, 1932; Hedges and Kornegay, 1973; Suttle and Mills, 1966) may also influence the bioavailability of iron. Oral iron can be given as paste or drinking water. Early administration of oral iron within the first few days of life will meet the iron needs of the suckling pig. However, it is critical to administer early before gut closure to large molecules (Harmon et al., 1974; Thoren-Tolling, 1975). This study was conducted to determine the efficacy of iron supplementation in drinking water or paste form in comparison with the injection of iron compounds in suckling pigs.

Coverage by the news media of the benefits and risks of medications

BACKGROUND

The news media are an important source of information about new medical treatments, but there is concern that some coverage may be inaccurate and overly enthusiastic.

METHODS

We studied coverage by U.S. news media of the benefits and risks of three medications that are used to prevent major diseases. The medications were pravastatin, a cholesterol-lowering drug for the prevention of cardiovascular disease; alendronate, a bisphosphonate for the treatment and prevention of osteoporosis; and aspirin, which is used for the prevention of cardiovascular disease. We analyzed a systematic probability sample of 180 newspaper articles (60 for each drug) and 27 television reports that appeared between 1994 and 1998.

RESULTS

Of the 207 stories, 83 (40 percent) did not report benefits quantitatively. Of the 124 that did, 103 (83 percent) reported relative benefits only, 3 (2 percent) absolute benefits only, and 18 (15 percent) both absolute and relative benefits. Of the 207 stories, 98 (47 percent) mentioned potential harm to patients, and only 63 (30 percent) mentioned costs. Of the 170 stories citing an expert or a scientific study, 85 (50 percent) cited at least one expert or study with a financial tie to a manufacturer of the drug that had been disclosed in the scientific literature. These ties were disclosed in only 33 (39 percent) of the 85 stories.

CONCLUSIONS

News-media stories about medications may include inadequate or incomplete information about the benefits, risks, and costs of the drugs as well as the financial ties between study groups or experts and pharmaceutical manufacturers.

Impaired intracellular trafficking of adeno-associated virus type 2 vectors limits efficient transduction of murine fibroblasts

Although adeno-associated virus type 2 (AAV) has gained attention as a potentially useful alternative to the more commonly used retrovirus- and adenovirus-based vectors for human gene therapy, efficient gene transfer and transgene expression by AAV vectors require that the following two obstacles be overcome. First, the target cell must express the receptor and the coreceptor for AAV infection, and second, the cell must allow for viral second-strand DNA synthesis. We now describe a third obstacle, impaired intracellular trafficking of AAV to the nucleus, which results in the lack of transgene expression in murine fibroblasts which do express the AAV receptor and the coreceptor and which are permissive for viral second-strand DNA synthesis. We document that AAV vectors bind efficiently and gain entry successfully into NIH 3T3 cells, but trafficking into the nucleus is significantly impaired in these cells. In contrast, viral trafficking to the nucleus in cells known to be efficiently transduced by AAV vectors is both rapid and efficient. The demonstration of yet another obstacle in AAV-mediated gene transfer has implications for the optimal use of these vectors in human gene therapy.

Human fibroblast growth factor receptor 1 is a co-receptor for infection by adeno-associated virus 2

Adeno-associated virus 2 (AAV)-based vectors have gained attention as a potentially useful alternative to the more commonly used retroviral and adenoviral vectors for human gene therapy. Although AAV uses the ubiquitously expressed cell surface heparan sulfate proteoglycan (HSPG) as a receptor, the transduction efficiency of AAV vectors varies greatly in different cells and tissues in vitro and in vivo. We demonstrate here that cell surface expression of HSPG alone is insufficient for AAV infection, and that AAV also requires human fibroblast growth factor receptor 1 (FGFR1) as a co-receptor for successful viral entry into the host cell. We document that cells that do not express either HSPG or FGFR1 fail to bind AAV and, consequently, are resistant to infection by AAV. These non-permissive cells are successfully transduced by AAV vectors after stable transfections with cDNAs encoding the murine HSPG and the human FGFR1. Furthermore, AAV infection of permissive cells, known to express both FGFR1 and the epidermal growth factor receptor, is abrogated by treatment of cells with basic fibroblast growth factor, but not with epidermal growth factor. The identification of FGFR1 as a co-receptor for AAV should provide new insights not only into its role in the life cycle of AAV, but also in the optimal use of AAV vectors in human gene therapy.

Identification of a novel genetic locus for familial cardiac myxomas and Carney complex

BACKGROUND

Intracardiac myxomas are significant causes of cardiovascular morbidity and mortality through embolic stroke and heart failure. In the autosomal dominant syndrome Carney complex, intracardiac myxomas arise in the setting of lentiginosis and other lesions associated with cutaneous hyperpigmentation, extracardiac myxomas, and nonmyxomatous tumors. Genetic factors that regulate cardiac tumor growth remain unknown.

METHODS AND RESULTS

We used the molecular genetic techniques of linkage analysis to study 4 kindreds affected by Carney complex to determine the genetic basis of this syndrome. Our investigation confirmed genetic heterogeneity of Carney complex. Moreover, genetic linkage analysis with polymorphic short tandem repeats on the long arm of chromosome 17 revealed maximal pairwise LOD scores of 5.9, 1.5, 1.8, and 2.9 for families YA, YB, YC01, and YC11, respectively. Haplotype analysis excluded a founder effect at this locus. These data identify a major 17 cM locus on chromosome 17q2 that contains the Carney complex disease gene.

CONCLUSIONS

The ultimate identification and analysis of the Carney complex disease gene at this human chromosome 17q2 locus will facilitate diagnosis and treatment of cardiac myxomas and will foster new concepts in regulation of cardiac cell growth and differentiation.

Adeno-associated virus type 2-mediated gene transfer: role of epidermal growth factor receptor protein tyrosine kinase in transgene expression

Adeno-associated virus type 2 (AAV), a single-stranded, DNA-containing, nonpathogenic human parvovirus, has gained attention as a potentially useful vector for human gene therapy. However, the transduction efficiency of AAV vectors varies greatly in different cells and tissues in vitro and in vivo. We have recently documented that a cellular tyrosine phosphoprotein, designated the single-stranded D-sequence-binding protein (ssD-BP), plays an important role in AAV-mediated transgene expression (K. Y. Qing et al., Proc. Natl. Acad. Sci. USA 94:10879-10884, 1997) and that a strong correlation exists between the phosphorylation state of the ssD-BP and AAV transduction efficiency in vitro as well as in vivo (K. Y. Qing et al., J. Virol. 72:1593-1599, 1998). In this report, we document that treatment of cells with specific inhibitors of the epidermal growth factor receptor protein tyrosine kinase (EGF-R PTK) activity, such as tyrphostin, leads to significant augmentation of AAV transduction efficiency, and phosphorylation of the ssD-BP is mediated by the EGF-R PTK. Treatment of cells with EGF results in phosphorylation of the ssD-BP, whereas treatment with tyrphostin causes dephosphorylation of the ssD-BP and consequently leads to increased expression of the transgene. Furthermore, AAV transduction efficiency inversely correlates with expression of the EGF-R in different cell types, and stable transfection of the EGF-R cDNA causes phosphorylation of the ssD-BP, leading to significant inhibition in AAV-mediated transgene expression which can be overcome by the tyrphostin treatment. These data suggest that the PTK activity of the EGF-R is a crucial determinant in the life cycle of AAV and that further studies on the interaction between the EGF-R and the ssD-BP may yield new insights not only into its role in the host cell but also in the successful use of AAV vectors in human gene therapy.

Adeno-associated virus type 2-mediated gene transfer: correlation of tyrosine phosphorylation of the cellular single-stranded D sequence-binding protein with transgene expression in human cells in vitro and murine tissues in vivo

Although the adeno-associated virus type 2 (AAV)-based vector system has gained attention as a potentially useful alternative to the more commonly used retroviral and adenoviral vectors for human gene therapy, the single-stranded nature of the viral genome, and consequently the rate-limiting second-strand viral DNA synthesis, significantly affect its transduction efficiency. We have identified a cellular tyrosine phosphoprotein, designated the single-stranded D sequence-binding protein (ssD-BP), which interacts specifically with the D sequence at the 3' end of the AAV genome and may prevent viral second-strand DNA synthesis in HeLa cells (K. Y. Qing et al., Proc. Natl. Acad. Sci. USA 94:10879-10884, 1997). In the present studies, we examined whether the phosphorylation state of the ssD-BP correlates with the ability of AAV to transduce various established and primary cells in vitro and murine tissues in vivo. The efficiencies of transduction of established human cells by a recombinant AAV vector containing the beta-galactosidase reporter gene were 293 > KB > HeLa, which did not correlate with the levels of AAV infectivity. However, the amounts of dephosphorylated ssD-BP which interacted with the minus-strand D probe were also as follows: 293 > KB > HeLa. Predominantly the phosphorylated form of the ssD-BP was detected in cells of the K562 line, a human erythroleukemia cell line, and in CD34+ primary human hematopoietic progenitor cells; consequently, the efficiencies of AAV-mediated transgene expression were significantly lower in these cells. Murine Sca-1+ lin- primary hematopoietic stem/progenitor cells contained predominantly the dephosphorylated form of the ssD-BP, and these cells could be efficiently transduced by AAV vectors. Dephosphorylation of the ssD-BP also correlated with expression of the adenovirus E4orf6 protein, known to induce AAV gene expression. A deletion mutation in the E4orf6 gene resulted in a failure to catalyze dephosphorylation of the ssD-BP. Extracts prepared from mouse brain, heart, liver, lung, and skeletal-muscle tissues, all of which are known to be highly permissive for AAV-mediated transgene expression, contained predominantly the dephosphorylated form of the ssD-BP. Thus, the efficiency of transduction by AAV vectors correlates well with the extent of the dephosphorylation state of the ssD-BP in vitro as well as in vivo. These data suggest that further studies on the cellular gene that encodes the ssD-BP may promote the successful use of AAV vectors in human gene therapy.

Adeno-associated virus type 2-mediated transduction in primary human bone marrow-derived CD34+ hematopoietic progenitor cells: donor variation and correlation of transgene expression with cellular differentiation

Although the adeno-associated virus type 2 (AAV) is known to possess a broad host range that transcends the species barrier, we suggested in an earlier study that AAV infection of human cells is receptor mediated (S. Ponnazhagan et al., J. Gen. Virol. 77:1111-1122, 1996). In the present studies, we investigated the ability of AAV to infect primary human hematopoietic progenitor cells capable of multilineage differentiation. Bone marrow-derived CD34+ cells from 12 hematologically normal volunteer donors were infected with a recombinant AAV containing the beta-galactosidase gene under the control of the cytomegalovirus immediate-early promoter (vCMVp-lacZ). Whereas 15 to 80% of the cells from approximately 50% of the donors showed various levels of lacZ gene expression, the expression was undetectable in cells from the remaining donors. However, if cells from both sets of donors were stimulated with various combinations of cytokines to induce differentiation into myeloid and lymphoid lineages following AAV infection, then the level of expression of the transduced gene increased up to 20-fold over a period of 14 days. The results of virus-binding assays suggested that the observed difference between the two groups was due to the differential susceptibility of CD34+ cells to AAV infection rather than to differences in transcription and translation of the transduced gene. To corroborate these results, CD34+ cells from the two donor groups, KB (human nasopharyngeal carcinoma) cells, and M07e (human megakaryocytic leukemia) cells were infected with vCMVp-lacZ. KB cells served as a positive control for AAV infection, and M07e cells served as a negative control. Whereas abundant hybridization to the single-stranded viral DNA on Southern blots was detected in KB and CD34+ cells that were positive for lacZ gene expression, little activity was detected in M07e and CD34+ cells that did not show expression of the lacZ gene. These results suggest that the levels of expression of the putative cellular receptor for AAV vary widely in CD34+ cells from different donors. These studies have implications for the potential use of AAV vectors in human gene therapy involving primary human primitive hematopoietic stem and progenitor cells.

A measure of peripheral nerve stimulation efficacy applicable to H-reflex studies

BACKGROUND

When H-reflexes are recorded during movement in human subjects, the stimulator current output is not a good indicator of sensory stimulation efficacy because of unavoidable nerve movement relative to the stimulus electrodes. Therefore, the M-wave amplitude has been used by researchers as an indicator of the efficacy of the stimulus. In this study we have examined the general validity of the hypothesis that the M-wave amplitude is directly proportional to the group I sensory afferent volley evoked by the stimulus.

METHODS

A nerve recording cuff, stimulating electrodes, and EMG recording electrodes were implanted in cats. Nerve cuff recordings of centrally propagating volleys evoked by electrical stimuli were directly compared to M-waves produced by the same stimuli. Compound action potentials (CAPs) recorded in the sciatic nerve were compared with soleus M-waves during either tibial nerve or soleus muscle nerve stimulation. CAPs in the ulnar nerve were correlated with flexor carpi ulnaris M-waves during ulnar nerve stimulation.

RESULTS AND CONCLUSIONS

Our findings indicate that for mixed nerve stimulation (e.g., tibial or ulnar nerve) the M-wave can be a reliable indicator of the centrally propagating sensory volley. Due to the high correlation between CAP and M-wave amplitude in these nerves, a small number of M-waves can give a good estimate of the size of the group I sensory volley. On the other hand, when nerves with only partially overlapping fibre diameter populations are stimulated (e.g., the soleus muscle nerve), the M-wave is not well correlated with the group I sensory volley and thus may not be used as a measure of the size of the input volley for H-reflex studies.

Carcinoid tumors of the lung: cytologic differential diagnosis in fine-needle aspirates

Pulmonary carcinoid tumors presenting as peripheral or coin lesions are rare and radiologically may resemble other primary or metastatic neoplasms in the lung. This study consisted of the cytologic evaluation of fine-needle aspirates from five peripheral carcinoid tumors of the lung with particular reference to the differences between the cytologic manifestations of this neoplasm and of small-cell carcinoma and well-differentiated adenocarcinoma. Aspirates of typical carcinoid tumors are characterized by isolated cells and loose aggregates of cells; spindle- and oval-shaped cells of uniform size with scanty, pale eosinophilic cytoplasm; and nuclei with evenly dispersed finely granular chromatin and usually prominent single micronucleoli with occasional macronucleoli. In contrast, the cells of small-cell carcinoma are pleomorphic and arranged in noncohesive loose aggregates, their cytoplasm is scanty, and they show nuclear molding. Their nuclei are hyperchromatic with fine to coarsely granular chromatin. The cells of well-differentiated adenocarcinoma are arranged in three-dimensional clusters or loose aggregates of relatively uniform cells with a columnar configuration. The nuclei are uniformly round and hyperchromatic with finely granular chromatin. Macronucleoli are usually prominent. This study demonstrates that cytologic analysis of fine-needle aspirates can play a significant role in the evaluation and management of peripheral lung tumors.