Structural transphobia is associated with psychological distress and suicidality in a large national sample of transgender adults

PURPOSE

Transgender adults face increasingly discriminatory laws/policies and prejudicial attitudes in many regions of the United States (US), yet research has neither quantified state-level transphobia using indicators of both, nor considered their collective association with transgender adults' psychological wellbeing, hindering the identification of this potential social determinant of transgender mental health inequity.

METHODS

We therefore used factor analysis to develop a more comprehensive structural transphobia measure encompassing 29 indicators of transphobic laws/policies and attitudes at the state level, which we linked to individual-level mental health data from a large national sample of 27,279 transgender adults (ages 18-100) residing in 45 US states and the District of Columbia (DC).

RESULTS

Controlling for individual- (i.e., demographics), interpersonal- (i.e., perceived discrimination), and state- (i.e., income inequality, religiosity) level covariates, transgender adults from US states with higher (vs. lower) levels of structural transphobia reported more severe past-month psychological distress and were more likely to endorse past-year and lifetime suicidal thoughts, plans, and attempts.

CONCLUSION

Findings provide novel evidence that state-level transphobic laws/policies and attitudes collectively shape a range of important mental health outcomes among transgender adults in the US. Multilevel intervention strategies, such as affirming mental health treatments, provider-training interventions, and supportive legislation, are needed to address structural transphobia's multifaceted nature and negative mental health consequences.

Transgender-Specific Adolescent Mental Health Provider Availability is Substantially Lower in States with More Restrictive Policies

OBJECTIVE

Transgender adolescents experience adversity accessing mental healthcare, which is exacerbated by transgender-specific mental health provider shortages in the United States. Factors associated with variability in transgender-specific mental health provider availability across states - especially at the macro-social level - have yet to be identified, hindering efforts to address these shortages. To remedy this gap, we queried whether transgender-specific adolescent mental health provider availability varied by states' transgender-specific policy climate.

METHOD

We quantified states' policy climate by factor-analyzing tallies of the presence/absence of 33 transgender-specific state laws/policies in six domains: parental/relationship recognition, nondiscrimination, education, healthcare, criminal justice, and identity documentation. We then tested whether states' transgender-specific policy climate was associated with rates of transgender-specific adolescent mental health providers - identified via Psychology Today - per transgender adolescent in all 50 states and the District of Columbia.

RESULTS

Transgender-specific adolescent mental health provider availability was substantially lower in states with more restrictive laws/policies for transgender people (rate ratio = 0.65, 95% CI [0.52, 0.81], p = .00017), controlling for state-level conservatism, religiosity, and urbanicity. States' transgender-specific policy climate was unrelated to rates of adolescent Attention-Deficit/Hyperactivity Disorder-specialty providers, Oppositional Defiant Disorder-specialty providers, and youth mental health provider shortages broadly, providing evidence for result specificity.

CONCLUSIONS

Transgender adolescents appear to have access to considerably fewer transgender-specific mental health providers in states with more restrictive laws/policies for transgender people, which may compound their already high mental health burden in these contexts. Intervention and policy efforts are needed to address these shortages, particularly in states with increasingly prohibitive laws/policies targeting transgender adolescents.

Future Directions in Mental Health Treatment with Stigmatized Youth

Stigma refers to societally-deemed inferiority associated with a circumstance, behavior, status, or identity. It manifests internally, interpersonally, and structurally. Decades of research indicate that all forms of stigma are associated with heightened risk for mental health problems (e.g., depression, PTSD, suicidality) in stigmatized youth (i.e., children, adolescents, and young adults with one or more stigmatized identities, such as youth of Color and transgender youth). Notably, studies find that stigmatized youth living in places with high structural stigma - defined as laws/policies and norms/attitudes that hurt stigmatized people - have a harder time accessing mental health treatment and are less able to benefit from it. In order to reduce youth mental health inequities, it is imperative for our field to better understand, and ultimately address, stigma at each of these levels. To facilitate this endeavor, we briefly review research on stigma and youth mental health treatment, with an emphasis on structural stigma, and present three future directions for research in this area: (1) directly addressing stigma in treatment, (2) training therapists in culturally responsive care, and (3) structural interventions. We conclude with recommendations for best practices in broader mental health treatment research.

Meta-analysis: Are Psychotherapies Less Effective for Black Youth in Communities With Higher Levels of Anti-Black Racism?

OBJECTIVE

To examine whether anti-Black cultural racism moderates the efficacy of psychotherapy interventions among youth.

METHOD

A subset of studies from a previous meta-analysis of 5 decades of youth psychotherapy randomized controlled trials was analyzed. Studies were published in English between 1963 and 2017 and identified through a systematic search. The 194 studies (N = 14,081 participants; age range, 2-19) across 34 states comprised 2,678 effect sizes (ESs) measuring mental health problems (eg, depression) targeted by interventions. Anti-Black cultural racism was operationalized using a composite index of 31 items measuring explicit racial attitudes (obtained from publicly available sources, eg, General Social Survey) aggregated to the state level and linked to the meta-analytic database. Analyses were conducted with samples of majority-Black (ie, ≥50% Black) (n = 36 studies) and majority-White (n = 158 studies) youth.

RESULTS

Two-level random-effects meta-regression analyses indicated that higher anti-Black cultural racism was associated with lower ESs for studies with majority-Black youth (β = -0.2, 95% CI [-0.35, -0.04], p = .02) but was unrelated to ESs for studies with majority-White youth (β = 0.0004, 95% CI [-0.03, 0.03], p = .98), controlling for relevant area-level covariates. In studies with majority-Black youth, mean ESs were significantly lower in states with the highest anti-Black cultural racism (>1 SD above the mean; Hedges' g = 0.19) compared with states with the lowest racism (<1 SD below the mean; Hedges' g = 0.60).

CONCLUSION

Psychotherapies tested with samples of majority-Black youth were significantly less effective in states with higher (vs lower) levels of anti-Black cultural racism, suggesting that anti-Black cultural racism may be one contextual moderator of treatment effect heterogeneity.

Evaluating a Modular Approach to Therapy for Children With Anxiety, Depression, Trauma, or Conduct Problems (MATCH) in School-Based Mental Health Care: Study Protocol for a Randomized Controlled Trial

Introduction: Schools have become a primary setting for providing mental health care to youths in the U.S. School-based interventions have proliferated, but their effects on mental health and academic outcomes remain understudied. In this study we will implement and evaluate the effects of a flexible multidiagnostic treatment called Modular Approach to Therapy for Children with Anxiety, Depression, Trauma, or Conduct Problems (MATCH) on students' mental health and academic outcomes.

Methods and Analysis: This is an assessor-blind randomized controlled effectiveness trial conducted across five school districts. School clinicians are randomized to either MATCH or usual care (UC) treatment conditions. The target sample includes 168 youths (ages 7–14) referred for mental health services and presenting with elevated symptoms of anxiety, depression, trauma, and/or conduct problems. Clinicians randomly assigned to MATCH or UC treat the youths who are assigned to them through normal school referral procedures. The project will evaluate the effectiveness of MATCH compared to UC on youths' mental health and school related outcomes and assess whether changes in school outcomes are mediated by changes in youth mental health.

Ethics and Dissemination: This study was approved by the Harvard University Institutional Review Board (IRB14-3365). We plan to publish the findings in peer-reviewed journals and present them at academic conferences.

Clinical Trial Registration:ClinicalTrials.gov ID: NCT02877875. Registered on August 24, 2016.

The effectiveness and acceptability of empirically supported treatments in gender minority youth across four randomized controlled trials

OBJECTIVE

Gender minority youth (i.e., children/adolescents whose gender identity and/or expression is inconsistent with their birth-assigned sex) experience elevated rates of emotional and behavioral problems relative to cisgender youth (who identify with their birth-assigned sex), which are not intrinsic to gender identity but attributable to unique minority stressors. Although empirically supported treatments have proven effective in treating these mental health concerns generally, randomized controlled trials have not examined effects for gender minority youth.

METHOD

To address this gap, we pooled data from clinically referred youth (N = 432; M(SD)age = 10.6(2.2); 55.1% White) assigned to empirically supported treatment conditions across four previous randomized controlled trials of modular psychotherapy. A proxy indicator of gender identity (i.e., youth's wish to be the opposite sex) was used to classify gender minority (n = 64) and cisgender (n = 368) youth. Youth- and caregiver-reported pretreatment internalizing and externalizing problems, treatment effectiveness on these domains, and treatment acceptability were compared across groups.

RESULTS

Gender minority youth reported more severe pretreatment internalizing and externalizing problems compared to cisgender youth; in contrast, their caregivers reported less severe problems. Although treatment was equally effective for both groups on most outcomes, gender minority youth's caregiver-reported externalizing problems improved more slowly and less reliably, and their self-reported internalizing problems were more likely to remain clinically elevated. Furthermore, gender minority youth reported lower treatment satisfaction.

CONCLUSIONS

While findings suggest that empirically supported treatments may effectively address many mental health problems for gender minority youth, they also underscore the need for treatment enhancements that improve acceptability and outcomes. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

GSK2245035, a TLR7 agonist, Does Not Increase Pregnancy Loss in Cynomolgus Monkeys

GSK2245035, a small molecule Toll-like Receptor 7 (TLR7) agonist developed for immunomodulatory treatment for allergic airways disease, aimed to reduce Th2 and enhance Th1/Treg responses to aeroallergens via the local induction of type I interferons (IFNs). GSK2245035 demonstrated selectivity for potent release of type I IFNs compared to TNF-α and IL-6, with dose dependent increases in the interferon inducible chemokine, IP-10, in the nasal compartment. Implantation and parturition require pro-inflammatory processes including IFNs, Interferon Stimulated Genes, TNFα and IP-10 while pregnancy requires immune regulation to maintain maternal fetal immune tolerance, and recombinant type I IFNs induced abortions in monkeys. Due to its mechanism of action, GSK2245035 was studied at pharmacologically and clinically relevant doses in a monkey pregnancy model. Monkeys received 0, 3 or 30 ng/kg/week GSK2245035 intranasally once weekly, from Day 20 postcoitum through Day 63 postpartum. Although systemic IFN-α and IP-10 levels were approximately 14.8 or 40 -fold (respectively) above predose levels at 3 or 30 ng/kg/week, respectively, there were no effects on pregnancy and infant outcome. Non-adverse effects included increased incidence of nasal discharge, increased maternal body temperature at 30 ng/kg/week and dose-dependent increases in maternal IP-10 and IFN-α and decreased infant anti-KLH IgM and IgG titers following KLH immunization at ≥3 ng/kg/week, relative to controls. Potentially, lower IFN-α and IP-10 levels as well as once-weekly intranasal dosing vs daily subcutaneous or intramuscular dosing with recombinant type I IFNs could explain the lack of pregnancy effects; however, there was an undesired impact on offspring immune function.

Approach for gait analysis in persons with limb loss including residuum and prosthesis socket dynamics

Musculoskeletal modeling and marker-based motion capture techniques are commonly used to quantify the motions of body segments, and the forces acting on them during human gait. However, when these techniques are applied to analyze the gait of people with lower limb loss, the clinically relevant interaction between the residual limb and prosthesis socket is typically overlooked. It is known that there is considerable motion and loading at the residuum-socket interface, yet traditional gait analysis techniques do not account for these factors due to the inability to place tracking markers on the residual limb inside of the socket. In the present work, we used a global optimization technique and anatomical constraints to estimate the motion and loading at the residuum-socket interface as part of standard gait analysis procedures. We systematically evaluated a range of parameters related to the residuum-socket interface, such as the number of degrees of freedom, and determined the configuration that yields the best compromise between faithfully tracking experimental marker positions while yielding anatomically realistic residuum-socket kinematics and loads that agree with data from the literature. Application of the present model to gait analysis for people with lower limb loss will deepen our understanding of the biomechanics of walking with a prosthesis, which should facilitate the development of enhanced rehabilitation protocols and improved assistive devices.

e-TC: Development and pilot testing of a web-based intervention to reduce anxiety and depression in survivors of testicular cancer

e-TC is an online intervention designed to address common psychosocial concerns of testicular cancer survivors. It aims to reduce anxiety, depression and fear of cancer recurrence by providing evidence-based information and psychological intervention. This paper details the development and pilot testing of e-TC. During pilot testing, 25 men (with varying psychological profiles) who had completed treatment for testicular cancer, 6 months to 5 years ago (which had not recurred), used e-TC over a 10-week period and provided quantitative and qualitative feedback on the feasibility and acceptability of the programme. Six men also completed a qualitative interview to provide detailed feedback on their experiences using e-TC. Fourteen men (56%) completed at least 80% of the programme. Participants reported a high level of satisfaction with the programme. Men's limited time was a barrier to programme use and completion, and participants suggested that men with a more recent diagnosis and a higher level of distress may be more likely to engage with the programme. e-TC appears to be a feasible and acceptable online intervention for survivors of testicular cancer. Findings from this study are currently being used to refine e-TC and guide the design of a larger efficacy study.

Control Points To Reduce Movement of Central Nervous System Tissue during Beef Slaughter

Consumption of central nervous system tissue (CNST) from cattle with bovine spongiform encephalopathy (BSE) is thought to cause the human neurological disease, variant Creutzfeldt-Jacob disease. To identify points of cross-contamination of beef carcasses with CNST, 55 young beef cattle were slaughtered and processed through a federally inspected multispecies abattoir. The objectives of this study were to evaluate CNST spread following the placement of a plug in the penetration site of the skull after captive bolt stunning, to evaluate cross-contamination of carcasses before and after splitting, to compare the effects of hot water pasteurization (84°C for 10 s) versus cold water wash (10°C for 30 s) for reducing CNST on the carcass, and to examine other possible sources of cross-contamination in the abattoir. Results indicated that the use of a plastic plug reduced CNST contamination near the bolt penetration site. This study also confirmed that carcass splitting resulted in an increase in CNST contamination at various areas of the carcass. Hot water pasteurization appeared to be an effective means of removing CNST contamination from carcasses in most of the areas sampled.

Heterogeneity of HIV incidence: a comparative analysis between fishing communities and in a neighbouring rural general population, Uganda, and implications for HIV control

OBJECTIVES

To describe HIV heterogeneity in rural Uganda using incidence data collected between January 2012 and December 2014 among fishing cohort (FC) and in an adjacent rural general population cohort (GPC).

METHODS

In the FC, eligible HIV high-risk adults aged 18+ years were enrolled, followed and HIV tested every 3 months. Demographic and sexual behaviour data were also collected. The GPC, approximately 47 km away from the FC, was followed through annual surveys, and sociodemographic and behavioural data collected. A subset of GPC with comparable risk profiles to the FC was selected. We presented sociodemographic and risk profiles and also computed stratified HIV incidence. Cox regression was used to assess factors associated with HIV incidence.

RESULTS

Overall HIV incidence was higher in the FC than in the 'high-risk' GPC, 6.04 and 0.56 per 100 person years at risk, respectively, with a rate ratio (RR) of 10.83 (95% CI 6.11 to 19.76). This was higher among those aged 18-24 years, unmarried and those with more than two sex partners in the past year, RR of 15.44, 22.99 and 19.29, respectively. In the FC, factors associated with high incidence in multivariate analysis were duration in the community and unprotected sex. The factors in the GPC were ethnicity, marital status and duration in the community.

CONCLUSIONS

We have observed a substantial heterogeneity in HIV incidence. The high incidence in fishing communities is contributing greatly to the overall HIV burden in Uganda, and thus urgent combination prevention efforts are needed towards national goal to reduce HIV epidemic.

Physical symptoms, coping styles and quality of life in recurrent ovarian cancer: a prospective population-based study over the last year of life

OBJECTIVE

The aim of this study was to describe the trajectory of physical symptoms, coping styles and quality of life (QoL) and the relationship between coping and QoL over the last year of life in women with recurrent ovarian cancer.

METHODS

The patient cohort were women recruited to the Australian Ovarian Cancer Study who subsequently experienced recurrent, invasive ovarian cancer and completed at least one psychosocial assessment (optimism, minimisation, hopelessness/helplessness, QoL) during the last year of life (n=217).

RESULTS

QoL declined sharply from six months before death. Lack of energy was the most prevalent symptom over three measurement periods (67-92%) and also the most severe. Anorexia (36-55%), abdominal swelling (33-58%), nausea (26-47%) and pain (26-43%) all increased in prevalence and severity towards the end of life. Higher optimism (p=0.009), higher minimisation (p=0.003) and lower helplessness/hopelessness (p=0.03) at baseline were significant predictors of subsequent higher QoL.

CONCLUSIONS

Progressive deterioration in quality of life may be an indicator of death within about six months and therefore should be an important consideration in decisions about subsequent treatment. Coping styles which independently predicted subsequent changes in QoL could potentially be targeted by interventions to minimise worsening QoL.

Choosing between the EORTC QLQ-C30 and FACT-G for measuring health-related quality of life in cancer clinical research: issues, evidence and recommendations

BACKGROUND

This review aims to assist cancer clinical researchers in choosing between the two most widely used measures of cancer-specific health-related quality of life: the European Organisation for the Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and Functional Assessment of Cancer Therapy-General (FACT-G).

MATERIALS AND METHODS

Information on QLQ-C30 and FACT-G content, scale structure, accessibility and availability was collated from websites and manuals. A systematic review was undertaken to identify all articles reporting on psychometric properties and information to assist interpretability. Evidence for reliability, validity and responsiveness was rated using a standardised checklist. Instrument properties were compared and contrasted to inform recommendations.

RESULTS

Psychometric evidence does not recommend one questionnaire over the other in general. However, there are important differences between the scale structure, social domains and tone that inform choice for any particular study.

CONCLUSIONS

Where research objectives are concerned with the impact of a specific tumour type, treatment or symptom, choice should be guided by the availability, content, scale structure and psychometric properties of relevant European Organisation for the Research and Treatment of Cancer versus Functional Assessment of Chronic Illness Therapy modules. Because the FACT-G combines symptoms and concerns within each scale, individual items should always be reviewed within the context of specific research objectives. Where these issues are indecisive, researchers are encouraged to use an algorithm at the end of the current article.

Inhibition of cleavage of a plant viral polyprotein by an inhibitor activity present in wheat germ and cowpea embryos

In rabbit reticulocyte lysate, the bottom component RNA of cowpea mosaic virus directs the synthesis of a 200,000-molecular-weight precursor protein (200K protein) that is cleaved during synthesis by a reticulocyte enzyme to form a 32K protein and a 170K protein. Cleavage of the 200K protein was found to be effectively inhibited by inhibitor activity in wheat germ and cowpea embryo extracts. The inhibitor was nondialyzable, precipitatable by ammonium sulfate, and partially stable at high temperatures. The activity appeared to be specific in that it caused no inhibition of the secondary cleavage reactions (cleavage of the 170K protein) at concentrations that were sufficient to cause complete inhibition of the primary cleavage reaction (cleavage of the 200K protein).

Screening for genital and anorectal sexually transmitted infections in HIV prevention trials in Africa

OBJECTIVES

To demonstrate the value of routine, basic sexually transmitted infection (STI) screening at enrolment into an HIV-1 vaccine feasibility cohort study and to highlight the importance of soliciting a history of receptive anal intercourse (RAI) in adults identified as "high risk".

METHODS

Routine STI screening was offered to adults at high risk of HIV-1 upon enrolment into a cohort study in preparation for HIV-1 vaccine trials. Risk behaviours and STI prevalence were summarised and the value of microscopy assessed. Associations between prevalent HIV-1 infection and RAI or prevalent STI were evaluated with multiple logistic regression.

RESULTS

Participants had a high burden of untreated STI. Symptom-directed management would have missed 67% of urethritis cases in men and 59% of cervicitis cases in women. RAI was reported by 36% of male and 18% of female participants. RAI was strongly associated with HIV-1 in men (adjusted odds ratio (aOR) 3.8; 95% CI 2.0 to 6.9) and independently associated with syphilis in women (aOR 12.9; 95% CI 3.4 to 48.7).

CONCLUSIONS

High-risk adults recruited for HIV-1 prevention trials carry a high STI burden. Symptom-directed treatment may miss many cases and simple laboratory-based screening can be done with little cost. Risk assessment should include questions about anal intercourse and whether condoms were used. STI screening, including specific assessment for anorectal disease, should be offered in African research settings recruiting participants at high risk of HIV-1 acquisition.

Genetic and phenotypic relationships of feed intake and measures of efficiency with growth and carcass merit of beef cattle1

Feed intake and efficiency of growth are economically important traits of beef cattle. This study determined the relationships of daily DMI, feed:gain ratio [F:G, which is the reciprocal of the efficiency of gain (G:F) and therefore increases as the efficiency of gain decreases and vice versa, residual feed intake (RFI), and partial efficiency of growth (efficiency of ADG, PEG) with growth and carcass merit of beef cattle. Residual feed intake was calculated from phenotypic regression (RFIp) or genetic regression (RFIg) of ADG and metabolic BW on DMI. An F1 half-sib pedigree file containing 28 sires, 321 dams, and 464 progeny produced from crosses between Alberta Hybrid cows and Angus, Charolais, or Alberta Hybrid bulls was used. Families averaged 20 progeny per sire (range = 3 to 56). Performance, ultrasound, and DMI data was available on all progeny, of which 381 had carcass data. Phenotypic and genetic parameters were obtained using SAS and ASREML software, respectively. Differences in RFIp and RFIg, respectively, between the most and least efficient steers (i.e., steers with the lowest PEG) were 5.59 and 6.84 kg of DM/d. Heritabilities for DMI, F:G, PEG, RFIp, and RFIg were 0.54 +/- 0.15, 0.41 +/- 0.15, 0.56 +/- 0.16, 0.21 +/- 0.12, and 0.42 +/- 0.15, respectively. The genetic (r = 0.92) and phenotypic (r = 0.97) correlations between RFIp and RFIg indicated that the 2 indices are very similar. Both indices of RFI were favorably correlated phenotypically (P < 0.001) and genetically with DMI, F:G, and PEG. Residual feed intake was tendentiously genetically correlated with ADG (r = 0.46 +/- 0.45) and metabolic BW (r = 0.27 +/- 0.33), albeit with high SE. Genetically, RFIg was independent of ADG and BW but showed a phenotypic correlation with ADG (r = -0.21; P < 0.05). Daily DMI was correlated genetically (r = 0.28) and phenotypically (r = 0.30) with F:G. Both DMI and F:G were strongly correlated with ADG (r > 0.50), but only DMI had strong genetic (r = 0.87 +/- 0.10) and phenotypic (r = 0.65) correlations with metabolic BW. Generally, the phenotypic and genetic correlations of RFI with carcass merit were not different from zero, except genetic correlations of RFI with ultrasound and carcass LM area and carcass lean yield and phenotypic correlations of RFI with backfat thickness (P < 0.01). Daily DMI had moderate to high phenotypic (P < 0.01) and genetic correlations with all the ultrasound and carcass traits. Depending on how RFI technology is applied, adjustment for body composition in addition to growth may be required to minimize the potential for correlated responses to selection in cattle.

Genetic and phenotypic relationships of serum leptin concentration with performance, efficiency of gain, and carcass merit of feedlot cattle1

Leptin is the hormone product of the obese gene that is synthesized and predominantly expressed by adipocytes. This study estimated the genetic variation in serum leptin concentration and evaluated the genetic and phenotypic relationships of serum leptin concentration with performance, efficiency of gain, and carcass merit. There were 464 steers with records for serum leptin concentration, performance, and efficiency of gain and 381 steers with records for carcass traits. The analyses included a total of 813 steers, including those without phenotypic records. Phenotypic and genetic parameter estimates were obtained using SAS and ASREML, respectively. Serum leptin concentration was moderately heritable (h2 = 0.34 +/- 0.13) and averaged 13.91 (SD = 5.74) ng/mL. Sire breed differences in serum leptin concentration correlated well with breed differences in body composition. Specifically, the serum leptin concentration was 20% greater in Angus-sired steers compared with Charolais-sired steers (P < 0.001). Consequently, ultrasound backfat (27%), carcass 12th-rib fat (31%), ultrasound marbling (14%), and carcass marbling (15%) were less in Charolais- than Angus-sired steers (P < 0.001). Conversely, carcass LM area (P = 0.05) and carcass lean meat yield (P < 0.001) were greater in Charolais- compared with Angus-sired steers. Steers with greater serum leptin concentration also had greater DMI (P < 0.001), greater residual feed intake (P = 0.04), and partial efficiency of growth (P = 0.01), but did not differ in feed conversion ratio (P > 0.10). Serum leptin concentration was correlated phenotypically with ultrasound backfat (r = 0.41; P < 0.001), carcass 12th-rib fat (r = 0.42; P < 0.001), ultrasound marbling (r = 0.25; P < 0.01), carcass marbling (r = 0.28; P < 0.01), ultrasound LM area (r = -0.19; P < 0.01), carcass LM area (r = -0.17; P < 0.05), lean meat yield (r = -0.38; P < 0.001), and yield grade (r = 0.32; P < 0.001). The corresponding genetic correlations were generally greater than the phenotypic correlations and included ultrasound backfat (r = 0.76 +/- 0.19), carcass 12th-rib fat (r = 0.54 +/- 0.23), ultrasound marbling (r = 0.27 +/- 0.22), carcass marbling (r = 0.76 +/- 0.21), ultrasound LM area (r = -0.71 +/- 0.19), carcass LM area (r = -0.75 +/- 0.20), lean meat yield (r = -0.59 +/- 0.22), and yield grade (r = 0.39 +/- 0.26). Serum leptin concentration can be a valuable tool that can be incorporated into appropriate selection programs to favorably improve the carcass merit of cattle.

Genetic and phenotypic relationships of feeding behavior and temperament with performance, feed efficiency, ultrasound, and carcass merit of beef cattle

Feeding behavior and temperament may be useful in genetic evaluations either as indicator traits for other economically relevant traits or because the behavior traits may have a direct economic value. We determined the variation in feeding behavior and temperament of beef cattle sired by Angus, Charolais, or Hybrid bulls and evaluated their associations with performance, efficiency, and carcass merit. The behavior traits were daily feeding duration, feeding head down (HD) time, feeding frequency (FF), and flight speed (FS, as a measure of temperament). A pedigree file of 813 animals forming 28 paternal half-sib families with about 20 progeny per sire was used. Performance, feeding behavior, and efficiency records were available on 464 animals of which 381 and 302 had records on carcass merit and flight speed, respectively. Large SE reflect the number of animals used. Direct heritability estimates were 0.28 +/- 0.12 for feeding duration, 0.33 +/- 0.12 for HD, 0.38 +/- 0.13 for FF, and 0.49 +/- 0.18 for FS. Feeding duration had a weak positive genetic (r(g)) correlation with HD (r(g) = 0.25 +/- 0.32) and FS (r(g) = 0.42 +/- 0.26) but a moderate negative genetic correlation with FF (r(g) = -0.40 +/- 0.30). Feeding duration had positive phenotypic (r(p)) and genetic correlations with DMI (r(p) = 0.27; r(g) = 0.56 +/- 0.20) and residual feed intake (RFI; r(p) = 0.49; r(g) = 0.57 +/- 0.28) but was unrelated phenotypically with feed conversion ratio [FCR; which is the reciprocal of the efficiency of growth (G:F)]. Feeding duration was negatively correlated with FCR (r(g) = -0.25 +/- 0.29). Feeding frequency had a moderate to high negative genetic correlation with DMI (r(g) = -0.74 +/- 0.15), FCR (r(g) = -0.52 +/- 0.21), and RFI (r(g) = -0.77 +/- 0.21). Flight speed was negatively correlated phenotypically with DMI (r(p) = -0.35) but was unrelated phenotypically with FCR or RFI. On the other hand, FS had a weak negative genetic correlation with DMI (r(g) = -0.11 +/- 0.26), a moderate genetic correlation with FCR (r(g) = 0.40 +/- 0.26), and a negative genetic correlation with RFI (r(g) = -0.59 +/- 0.45). The results indicate that behavior traits may contribute to the variation in the efficiency of growth of beef cattle, and there are potential correlated responses to selection to improve efficiency. Feeding behavior and temperament may need to be included in the definition of beef cattle breeding goals, and approaches such as the culling of unmanageable cattle and the introduction of correct handling facilities or early life provision of appropriate experiences to improve handling will be useful.

Relationships of feedlot feed efficiency, performance, and feeding behavior with metabolic rate, methane production, and energy partitioning in beef cattle

Residual feed intake (RFI) is the difference between the actual and expected feed intake of an animal based on its BW and growth rate over a specified period. The biological mechanisms underlying the variation in feed efficiency in animals with similar BW and growth rate are not well understood. This study determined the relationship of feedlot feed efficiency, performance, and feeding behavior with digestion and energy partitioning of 27 steers. The steers were selected from a total of 306 animals based on their RFI following feedlot tests at the University of Alberta Kinsella Research Station. Selected steers were ranked into high RFI (RFI > 0.5 SD above the mean, n = 11), medium RFI (RFI +/- 0.5 SD above and below the mean, n = 8), and low RFI (RFI < -0.5 SD below the mean, n = 8). The respective BW +/- SD for the RFI groups were 495.6 +/- 12.7, 529.1 +/- 18.6, and 501.2 +/- 15.5 kg. Digestibility and calorimetry trials were performed on a corn-or barley-based concentrate diet in yr 1 and 2, respectively, at 2.5 x maintenance requirements. Mean DMI (g/kg of BW(0.75)) during the measurements for high-, medium-, and low-RFI groups, respectively, were 82.7 +/- 2.0, 78.8 +/- 2.6, and 81.8 +/- 2.5 and did not differ (P > 0.10). Residual feed intake was correlated with daily methane production and energy lost as methane (r = 0.44; P < 0.05). Methane production was 28 and 24% less in low-RFI animals compared with high- and medium-RFI animals, respectively. Residual feed intake tended to be associated (P < 0.10) with apparent digestibilities of DM (r = -0.33) and CP (r = -0.34). The RFI of steers was correlated with DE (r = -0.41; P < 0.05), ME (r = -0.44; P < 0.05), heat production (HP; r = 0.68; P < 0.001), and retained energy (RE; r = -0.67; P < 0.001; energy values are expressed in kcal/kg of BW(0.75)). Feedlot partial efficiency of growth was correlated (P < 0.01) with methane production (r = -0.55), DE (r = 0.46), ME (r = 0.49), HP (r = -0.50), and RE (r = 0.62). With the exception of HP (r = 0.37; P < 0.05), feed conversion ratio was unrelated to the traits considered in the study. Feeding duration was correlated (P < 0.01) with apparent digestibility of DM (r = -0.55), CP (r = -0.47), methane production (r = 0.51), DE (r = -0.52), ME (r = -0.55), and RE (r = -0.60). These results have practical implications for the selection of animals that eat less at a similar BW and growth rate and for the environmental sustainability of beef production.

Different measures of energetic efficiency and their phenotypic relationships with growth, feed intake, and ultrasound and carcass merit in hybrid cattle1

Residual feed intake (RFI) has been proposed as an index for determining beef cattle energetic efficiency. Although the relationship of RFI with feed conversion ratio (FCR) is well established, little is known about how RFI compares to other measures of efficiency. This study examined the phenotypic relationships among different measures of energetic efficiency with growth, feed intake, and ultrasound and carcass merit of hybrid cattle (n = 150). Dry matter intake, ME intake (MEI), ADG, metabolic weight (MWT), and FCR during the test averaged 10.29 kg/d (SD = 1.62), 1,185.45 kJ/(kg0.75 x d) (SD = 114.69), 1.42 kg/d (SD = 0.25), 86.67 kg0.75 (SD = 10.21), and 7.27 kg of DM/kg of gain (SD = 1.00), respectively. Residual feed intake averaged 0.00 kg/d and ranged from -2.25 kg/d (most efficient) to 2.61 kg/d (least efficient). Dry matter intake (r = 0.75), MEI (r = 0.83), and FCR (r = 0.62) were correlated with RFI (P < 0.001) and were higher for animals with high (>0.5 SD) RFI vs. those with medium (+/-0.5 SD) or low (<0.5 SD) RFI (P < 0.001). Partial efficiency of growth (PEG; energetic efficiency for ADG) was correlated with RFI (r = -0.89, P < 0.001) and was lower (P < 0.001) for high- vs. medium- or low-RFI animals. However, RFI was not related to ADG (r = -0.03), MWT (r = -0.02), relative growth rate (RGR; growth relative to instantaneous body size; r = -0.04), or Kleiber ratio (KR; ADG per unit of MWT; r = -0.004). Also, DMI was correlated (P < 0.01) with ADG (r = 0.66), MWT (r = 0.49), FCR (r = 0.49), PEG (r = -0.52), RGR (r = 0.18), and KR (r = 0.36). Additionally, FCR was correlated (P < 0.001) with ADG (r = -0.63), PEG (r = -0.83), RGR (r = -0.75), and KR (r = -0.73), but not with MWT (r = 0.07). Correlations of measures of efficiency with ultrasound or carcass traits generally were not different from zero except for correlations of RFI, FCR, and PEG, respectively, with backfat gain (r = 0.30, 0.20, and -0.30), ultrasound backfat (r = 0.19, 0.21, and -0.25), grade fat (r = 0.25, 0.19, and -0.27), lean meat yield (r = -0.22, -0.18, and 0.24), and yield grade (r = 0.28, 0.24, and -0.25). These phenotypic relationships indicate that, compared with other measures of energetic efficiency, RFI should have a greater potential to improve overall production efficiency and PEG above maintenance, and lead to minimal correlated changes in carcass merit without altering the growth and body size of different animals.

Identification of a novel, human multilymphoid progenitor in cord blood

The earliest stages of lymphoid commitment from human pluripotent hematopoietic stem cells have not been defined. A clonogenic subpopulation of CD34(+)CD38(-) cord blood cells were identified that expressed high levels of the CD7 antigen and possessed only lymphoid potential. CD34(+)CD38(-)CD7(+) (CD7(+)) cells uniformly coexpressed CD45RA and HLA-DR; c-kit and Thy-1 expression was absent to low. Clonal analysis demonstrated that single CD7(+) cells could generate B cells, natural killer cells, and dendritic cells but were devoid of myeloid or erythroid potential. In contrast, control CD34(+)CD38(-)CD7(-) (CD7(-)) cells generated both lymphoid and myelo-erythroid cells. The lymphoid potential (generation of lymphoid progeny in bulk and single cell cultures) of CD7(+) cells was equivalent to that of the pluripotent CD7(-) cells. RNA expression studies showed that CD7(+) cells expressed PU.1 and GATA-3, but did not express Pax-5, terminal deoxynucleotide transferase, or CD3epsilon. In contrast to the previously described murine common lymphoid progenitor, the alpha chain of the receptor for interleukin-7 was not detected by fluorescence-activated cell sorting analysis or RNA polymerase chain reaction in CD7(+) cells. These studies identify a clonogenic lymphoid progenitor with both B-cell and natural killer cell lineage potential with a molecular profile that suggests a developmental stage more primitive than previously identified lymphoid progenitors. The CD7(+) phenotype distinguishes primitive human lymphoid progenitors from pluripotent stem cells, thus allowing the study of regulation of early human lymphopoiesis and providing an alternative to pluripotent stem cells for genetic manipulation and transplantation. (Blood. 2001;97:3683-3690)

Epidemiological evidence for a relationship between life events, coping style, and personality factors in the development of breast cancer

OBJECTIVE

Review empirical evidence for a relationship between psychosocial factors and breast cancer development.

METHODS

Standardised quality assessment criteria were utilised to assess the evidence of psychosocial predictors of breast cancer development in the following domains: (a) stressful life events, (b) coping style, (c) social support, and (d) emotional and personality factors.

RESULTS

Few well-designed studies report any association between life events and breast cancer, the exception being two small studies using the Life Events and Difficulties Schedule (LEDS) reporting an association between severely threatening events and breast cancer risk. Seven studies show anger repression or alexithymia are predictors, the strongest evidence suggesting younger women are at increased risk. There is no evidence that social support, chronic anxiety, or depression affects breast cancer development. With the exception of rationality/anti-emotionality, personality factors do not predict breast cancer risk.

CONCLUSION

The evidence for a relationship between psychosocial factors and breast cancer is weak. The strongest predictors are emotional repression and severe life events. Future research would benefit from theoretical grounding and greater methodological rigour. Recommendations are given.

Proteolysis of cubitus interruptus in Drosophila requires phosphorylation by protein kinase A

The Hedgehog signal transduction pathway is involved in diverse patterning events in many organisms. In Drosophila, Hedgehog signaling regulates transcription of target genes by modifying the activity of the DNA-binding protein Cubitus interruptus (Ci). Hedgehog signaling inhibits proteolytic cleavage of full-length Ci (Ci-155) to Ci-75, a form that represses some target genes, and also converts the full-length form to a potent transcriptional activator. Reduction of protein kinase A (PKA) activity also leads to accumulation of full-length Ci and to ectopic expression of Hedgehog target genes, prompting the hypothesis that PKA might normally promote cleavage to Ci-75 by directly phosphorylating Ci-155. Here we show that a mutant form of Ci lacking five potential PKA phosphorylation sites (Ci5m) is not detectably cleaved to Ci-75 in Drosophila embryos. Moreover, changes in PKA activity dramatically altered levels of full-length wild-type Ci in embryos and imaginal discs, but did not significantly alter full-length Ci5m levels. We corroborate these results by showing that Ci5m is more active than wild-type Ci at inducing ectopic transcription of the Hh target gene wingless in embryos and that inhibition of PKA enhances induction of wingless by wild-type Ci but not by Ci5m. We therefore propose that PKA phosphorylation of Ci is required for the proteolysis of Ci-155 to Ci-75 in vivo. We also show that the activity of Ci5m remains Hedgehog responsive if expressed at low levels, providing further evidence that the full-length form of Ci undergoes a Hedgehog-dependent activation step.

Predictors of breast cancer in women recalled following screening

BACKGROUND

Established risk factors are associated with between 25 and 56% of breast cancer cases, but the relative importance and relevance to different age groups is unclear.

METHODS

This case-control study examines established risk factors in 298 women with breast cancer and 1926 women without breast cancer aged 40-87 who were recalled for assessment following routine mammography.

RESULTS

The cancer group were significantly older than the non-cancer group (F1,222 = 107.6; P < 0.0001). Postmenopausal obesity increased the odds of developing breast cancer (OR: 2.35; CI: 1.33-4.16). The breast cancer group were more likely to have used oral contraceptives (OR: 1.50; CI: 1.09-2.05), and women who used contraceptives for more than 10 years in total were at the highest risk (OR: 1.73; CI: 1.13-2.65). Daily consumption of alcohol was also associated with increased risk of developing breast cancer (OR: 1.62; CI: 1.13-2.33). Reproductive factors and a family history of breast cancer did not affect the odds of developing breast cancer and the reasons for these findings are explored.

CONCLUSIONS

Results suggest that the effects of weight reduction in reducing postmenopausal breast cancer risk should be assessed.

Stable transduction of quiescent CD34(+)CD38(-) human hematopoietic cells by HIV-1-based lentiviral vectors

We compared the efficiency of transduction by an HIV-1-based lentiviral vector to that by a Moloney murine leukemia virus (MLV) retroviral vector, using stringent in vitro assays of primitive, quiescent human hematopoietic progenitor cells. Each construct contained the enhanced green fluorescent protein (GFP) as a reporter gene. The lentiviral vector, but not the MLV vector, expressed GFP in nondivided CD34(+) cells (45.5% GFP+) and in CD34(+)CD38(-) cells in G0 (12.4% GFP+), 48 hr after transduction. However, GFP could also be detected short-term in CD34(+) cells transduced with a lentiviral vector that contained a mutated integrase gene. The level of stable transduction from integrated vector was determined after extended long-term bone marrow culture. Both MLV vectors and lentiviral vectors efficiently transduced cytokine-stimulated CD34(+) cells. The MLV vector did not transduce more primitive, quiescent CD34(+)CD38(-) cells (n = 8). In contrast, stable transduction of CD34(+)CD38(-) cells by the lentiviral vector was seen for over 15 weeks of extended long-term culture (9.2 +/- 5.2%, n = 7). GFP expression in clones from single CD34(+)CD38(-) cells confirmed efficient, stable lentiviral transduction in 29% of early and late-proliferating cells. In the absence of growth factors during transduction, only the lentiviral vector was able to transduce CD34(+) and CD34(+)CD38(-) cells (13.5 +/- 2.5%, n = 11 and 12.2 +/- 9.7%, n = 4, respectively). The lentiviral vector is clearly superior to the MLV vector for transduction of quiescent, primitive human hematopoietic progenitor cells and may provide therapeutically useful levels of gene transfer into human hematopoietic stem cells.

The use of a digital imaging system in a dermatologic surgery practice

BACKGROUND

Digital imaging systems are now commercially available, reasonably affordable, and much improved in quality.

OBJECTIVE

To present our 2-year experience with a digital imaging system in Mohs and dermatologic surgery practice and to inform readers of the equipment needed, its cost, uses, advantages, and disadvantages compared with conventional photography.

CONCLUSION

The advantages of a digital imaging system include quality images, easy storage and retrieval, and cost-effectiveness. The disadvantages are few: a substantial initial investment and the training of office personnel in its use and maintenance. Uses include monitoring nevomelanocytic lesions, surgical photo documentation, medical records, and a photographic research database.

The p38 and ERK MAP kinase pathways cooperate to activate Ternary Complex Factors and c-fos transcription in response to UV light

We investigated the activation of c-fos transcription following UV irradiation, a 'stress' stimulus. In both HeLa TK- and NIH 3T3 cells the Serum Response Element is required for efficient UV-induced c-fos transcription, and in HeLa TK- cells the Ternary Complex Factor (TCF) binding site contributes substantially to activation. Consistent with this, UV irradiation activates LexA-TCF fusion proteins more strongly in HeLa TK- than in NIH 3T3 cells. The TCF C-termini of the TCFs are substrates for UV-induced MAP kinases: both the Elk-1 and SAP-1a C-termini are efficiently phosphorylated by the p38 MAPK, but only the Elk-1 C-terminus is a good substrate for the SAPK/JNKs. The specificity and activation kinetics of TCF C-terminal kinases, and the susceptibility of transcriptional activation by LexA-TCF fusion proteins to specific inhibitors of different MAPK pathways, show that both the ERK and p38 MAPK pathways contribute to TCF activation in response to UV irradiation. Activity of both these pathways is also required for the response of the c-fos gene itself to UV stimulation.

Integration of growth factor signals at the c-fos serum response element

A transcription factor ternary complex composed of serum response factor (SRF) and a second factor, ternary complex factor (TCF), mediates the response of the c-fos Serum Response Element to growth factors and mitogens. In NIH3T3 fibroblasts, TCF binding is required for transcriptional activation by the SRE in response to activation of the Ras-Raf-ERK pathway. We compared the properties of three members of the TCF family, Elk-1, SAP-1 and SAP-2 (ERP/NET). Although all the proteins contain sequences required for ternary complex formation with SRF, only Elk-1 and SAP-1 appear to interact with the c-fos SRE efficiently in vivo. Each TCF contains a C-terminal activation domain capable of transcriptional activation in response to activation of the Ras-Raf-ERK pathway, and this is dependent on the integrity of S/T-P motifs conserved between all the TCF family members. In contrast, activation of the SRE by whole serum and the mitogenic phospholipid LPA requires SRF binding alone. Constitutively activated members of the Rho subfamily of Ras-like GTPases are also capable of inducing activation of the SRE in the absence of TCF; unlike activated Ras itself, these proteins do not activate the TCFs in NIH3T3 cells. At the SRE, SRF- and TCF-linked signalling pathways act synergistically to potentiate transcription.

Hormonal status, metabolic changes, and resting metabolic rate in beef heifers undergoing compensatory growth

Twelve recently weaned Hereford crossbred heifers weighing 227 kg (12 kg SD) and aged 230 d (8 d SD) on d 0 were used to investigate physiological responses associated with compensatory growth. Six heifers were allotted to ad libitum intake (ADLIB) and six were restricted to a maintenance diet for 95 d followed by realimentation (REST). Plasma collected from all heifers during feed restriction (d 0, 20, 48) and realimentation (d 104, 125, 153, 195) was analyzed for growth hormone (GH), insulin-like growth factor I (IGF-I), thyroid hormones (thyroxine [T4] and triiodothyronine [T3]), insulin, glucose, nonesterified fatty acids (NEFA), blood urea nitrogen (BUN), and 3-methyl histidine (3-MH). Resting metabolic rate (RMR) was measured 5 d before and 15 and 36 d after the beginning of realimentation. Feed restriction was associated with higher (P < .05) plasma concentrations of GH and NEFA and lower (P < .05) concentrations of IGF-I, T4, T3, insulin, and glucose. The BUN concentration was lower (P = .05) in REST than in ADLIB heifers on d 48, whereas 3-MH was not affected during the first 48 d of feed restriction. The RMR was lower (P < .05) in REST than in ADLIB heifers during feed restriction. During realimentation, the ADG of REST heifers was higher (P = .001) than that of ADLIB heifers. Concentrations of IGF-I, insulin, glucose, and NEFA in REST heifers increased and no differences (P > .05) between treatments were observed on d 104 (d 10 of realimentation) and thereafter. Conversely, GH concentration in REST heifers remained elevated through d 104 but dropped to ADLIB levels by d 125 (d 31 of realimentation). The T4 and T3 concentrations remained lower (P < .05) in REST than in ADLIB heifers after 10 d of realimentation but rose to control levels by d 31 of realimentation. The RMR was lower (P < .05) in REST than in ADLIB heifers 15 d into realimentation; however, no difference was found between treatments by d 36 of realimentation. These results indicate that enhanced growth rates in the early phase of compensatory growth are associated with the physiological response of the GH-IGF-I-insulin axis coupled with reduced maintenance requirement due to slower metabolic rate in restricted-refed heifers.

Comparative analysis of the ternary complex factors Elk-1, SAP-1a and SAP-2 (ERP/NET)

A transcription factor ternary complex composed of Serum Response Factor (SRF) and Ternary Complex Factor (TCF) mediates the response of the c-fos Serum Response Element (SRE) to growth factors and mitogens. Three Ets domain proteins, Elk-1, SAP-1 and ERP/NET, have been reported to have the properties of TCF. Here we compare Elk-1 and SAP-1a with the human ERP/NET homologue SAP-2. All three TCF RNAs are ubiquitously expressed at similar relative levels. All three proteins contain conserved regions that interact with SRF and the c-fos SRE with comparable efficiency, but in vitro complex formation by SAP-2 is strongly inhibited by its C-terminal sequences. Similarly, only Elk-1 and SAP-1a efficiently bind the c-fos SRE in vivo; ternary complex formation by SAP-2 is weak and is substantially unaffected by serum stimulation or v-ras co-expression. All three TCFs contain C-terminal transcriptional activation domains that are phosphorylated following growth factor stimulation. Activation requires conserved S/T-P motifs found in all the TCF family members. Each TCF activation domain can be phosphorylated in vitro by partially purified ERK2, and ERK activation in vivo is sufficient to potentiate transcriptional activation.

Beau's lines and pyogenic granulomas following hand trauma

We report two cases of trauma-induced Beau's lines accompanied by pyogenic granulomas of the proximal nail folds of the affected fingers. The preceding trauma was not directly to the nail matrix but was more proximal, on the palm in one case and the arm in the other. The simultaneous occurrence of Beau's lines and pyogenic granulomas following trauma has not been reported previously in the literature.

Casemix classification and health care of the elderly

The Australian national diagnosis-related groups (AN-DRGs) patient classification has highlighted the distinction between different categories of inpatient care and ambulatory care, and the need for an explicit definition of boundaries of associated categories. A nationally consistent definition of these patient care categories, and of episodes of care according to illness acuity, will facilitate the design of additional casemix classifications to supplement AN-DRGs. Specific features of the AN-DRGs classification will have a major impact on health care of the elderly through incentives created by funding arrangements based on this classification. The use of age as an AN-DRG classification criterion, as a surrogate for definitive secondary diagnoses, should be regarded as an interim measure pending improvement in medical record documentation, further analysis of the relationship of age partitions to these secondary diagnoses, and ongoing improvement of AN-DRG design. The complex process of development of casemix classifications for subacute and ambulatory care has commenced, and will also have a profound impact on health care of the elderly and on all specialities concerned with both acute and chronic illness, again because of financial incentives in the classification design. Funding for development and refinement of each of these casemix classifications will be required if the anticipated benefits are to occur.

Multiagent pharmacotherapy to enhance skin flap survival: lack of additive effect of nitroglycerin and allopurinol

Pathological vasospasm and free radical production contribute to skin flap necrosis. This study was undertaken to determine if postoperative combination therapy with the vasodilator nitroglycerin and the anti-free radical agent allopurinol would result in an additive enhancement of skin flap survival in the rat model. Thirty-one Sprague-Dawley rats were randomized into four groups and two cranially based dorsal skin flaps were raised on each rat. Both surgeon and data collector were blinded to treatments and all agents were given postoperatively. Control rats demonstrated 51 +/- 7.4% skin flap survival. Mean flap survival was significantly increased in groups receiving single agent therapy with either transdermal nitroglycerin (63 +/- 12% survival, mean +/- 2 SEM, p < 0.05) or intravenous allopurinol (62 +/- 10% survival, p < 0.01). No additional survival was seen in rats receiving both agents, which displayed 61 +/- 13% survival (p < 0.05, compared with controls). This study provides the first well-controlled demonstration that postoperatively applied transdermal nitroglycerin significantly enhances skin flap survival and includes a discussion of reasons for lack of additive effect of these agents.

Juvenile basal cell carcinoma

A 17-year-old youth had a solitary basal cell carcinoma of the nose. This malignancy is rare in children and usually occurs with another disease or syndrome. The de novo form in this patient is especially rare.

How the structure of an adenine tract depends on sequence context: a new model for the structure of TnAn DNA sequences

We present a new model to explain the bending and local structural properties of TnAn sequences in DNA. Current models suggest that an adenine tract has the same unusual structure when found in a TnAn sequence as it has when surrounded by mixed-sequence B-DNA. On the basis of hydroxyl radical cleavage patterns of several TnAn sequences, we instead propose that the T2A2 or T3A3 core of such sequences is B-DNA-like but that adenines and thymines outside of this core, if sufficient in number, can form the unusual structure adopted by adenine tracts surrounded by mixed sequence DNA. We pursued further the structure of T7A7N7, a molecule which exhibits reduced electrophoretic mobility on native polyacrylamide gels and is therefore presumed to be bent. We attempted to mimic the structure of T7A7N7 that was predicted by our model by designing two new sequences, one in which the T3A3 core of T7A7N7 is substituted by six nucleotides of mixed sequence (N6) and the other in which the T2A2 core is replaced by N4. Hydroxyl radical cleavage patterns of all three molecules are nearly indistinguishable. All three molecules run anomalously slowly on a native polyacrylamide gel, with the mobility of T4N6A4N7 > T7A7N7 approximately T5N4A5N7. Analysis of the hydroxyl radical cutting pattern of T7A7N7 by Fourier transformation reveals the occurrence of an unusual structure at intervals of approximately 10 bp, a periodicity which is not evident in the sequence of the DNA.

Evidence for voltage modulation of IL-2 production in mitogen-stimulated human peripheral blood lymphocytes

The membrane potential of human PBMC was modulated in culture by isotonic high extracellular K+ (K+e), or the K+ channel blocker, charybdotoxin (ChTX), to determine the effect of depolarization on stimulated proliferation, IL-2 elaboration, and gene expression. In serum-free cultures, ChTX and high [K+]e induced a specific dose-dependent decrease in IL-2 production. ChTX inhibited proliferation of PBMC and purified T cells, decreased IL-2 elaboration 15 h after stimulation by 78.4 +/- 5.3% (n = 5), and decreased IL-2 mRNA steady-state levels by 80% between 8 and 10 h after stimulation. The IC50 for ChTX-inhibition of IL-2 elaboration and IL-2 mRNA were both 1 nM. Similarly, high [K+]e inhibited proliferation with an IC50 of 38.9 +/- 1.1 mM (n = 13), decreased IL-2 elaboration with an IC50 of 21.3 +/- 1.2 mM (n = 6), and decreased IL-2 mRNA steady-state levels with an IC50 of 18 mM. The sensitivities of both IL-2 production and proliferation to depolarization were substantially reduced by calcium, serum, and exogenous rIL-2. From these findings we conclude that membrane potential may contribute to the control of immune responsiveness in vivo.

Evidence for voltage modulation of IL-2 production in mitogen-stimulated human peripheral blood lymphocytes

The membrane potential of human PBMC was modulated in culture by isotonic high extracellular K+ (K+e), or the K+ channel blocker, charybdotoxin (ChTX), to determine the effect of depolarization on stimulated proliferation, IL-2 elaboration, and gene expression. In serum-free cultures, ChTX and high [K+]e induced a specific dose-dependent decrease in IL-2 production. ChTX inhibited proliferation of PBMC and purified T cells, decreased IL-2 elaboration 15 h after stimulation by 78.4 +/- 5.3% (n = 5), and decreased IL-2 mRNA steady-state levels by 80% between 8 and 10 h after stimulation. The IC50 for ChTX-inhibition of IL-2 elaboration and IL-2 mRNA were both 1 nM. Similarly, high [K+]e inhibited proliferation with an IC50 of 38.9 +/- 1.1 mM (n = 13), decreased IL-2 elaboration with an IC50 of 21.3 +/- 1.2 mM (n = 6), and decreased IL-2 mRNA steady-state levels with an IC50 of 18 mM. The sensitivities of both IL-2 production and proliferation to depolarization were substantially reduced by calcium, serum, and exogenous rIL-2. From these findings we conclude that membrane potential may contribute to the control of immune responsiveness in vivo.

Analysis of puberty-accelerating pheromones

Two experiments were performed to test putative puberty-accelerating pheromones. In the first experiment, 37 weanling female house mice of the ICR strain were exposed to 1 of the following 3 treatments: an airborne mixture of 0.05 M isoamylamine and 0.05 M isobutylamine, fresh male mouse urine, or distilled water, as the control. Neither the amine mixture nor the male urine accelerated first estrus in the mice following airborne exposure to these compounds. In the second experiment, 37 weanling female mice of the same strain were exposed to the same chemicals as in the first experiment by direct contact to the oro-nasal groove. The mixture of isoamylamine and isobutylamine did not accelerate puberty, but direct contact with the male urine accelerated puberty as evidenced by uterine weights.

The effect of breed-type and castration on bone growth and distribution in cattle

Data from carcasses of 210 cattle (119 bulls and 91 steers) from 4 breed types, serially slaughtered from approximately 200-800 kg kg liveweight were used to test the hypothesis of similar gender dimorphism among breeds in relation to carcass bone growth and distribution. Relative to total bone weight, breed types tended to have similar growth rates for all bones other than the cervical vertebrae, ribs, tibia and fibula, and tarsus. Adjusted to the same total bone weight there were significant differences among breed types in bone weight distribution, but the differences were very small and probably of little economic importance. Castration stimulated growth of the lumbar vertebrae, hindlimb bones, patella and hindquarter bones but inhibited growth of the ribs, scapula, carpus, forelimb bone, and forequarter bone. At the same total bone weight, steers as compared to bulls showed a shift in bone weight distribution towards the hindquarter, pistol and long bones. There were small but significant breed x gender interactions in the distribution of some bones.

The injured canine cervical spine after six months of healing. An in vitro three-dimensional study

The cervical spine is a common site of spinal injuries. The stability of an injured cervical spine is not only dependent on injury severity, but also on the degree of healing time. Using a canine model, three injuries of varying degrees of severity were surgically produced at the C4-C5 level and allowed to heal for 6 months. No internal or external support was provided. The harvested cervical spines (C2-C7) were subjected to three-dimensional biomechanical testing by applying individually six pure moments. The resulting three-dimensional displacements were recorded using stereophotogrammetry, and the intervertebral motions were calculated. The results are compared with the in vivo behavior of the same specimens and with an in vitro control group. At 1 N-m, the average flexion-extension range of motion (ROM) for the intact C4-C5 level was 24.5 degrees (standard deviation [SD], 6.6 degrees). A facetectomy at this level significantly increased the in vitro ROM to 51.1 degrees (SD, 4.4 degrees). The in vitro ROM decreased to 19.8 degrees (SD, 7.3 degrees) in the facetectomized group of this study, which were allowed to heal for 6 months before death. Similar results were obtained in axial rotation and lateral bending. The findings show that after 6 months of healing, the injured canine spine, although acutely hypermobile, exhibited biomechanical characteristics that were not different from those of the normal intact specimens.