A core outcome domain set to assess cutaneous neurofibromas related to neurofibromatosis type 1 in clinical trials

BACKGROUND

Cutaneous neurofibromas (cNF) are considered one of the highest burdens of neurofibromatosis type 1 (NF1). To date, no medical treatment can cure cNF or prevent their development. In that context, there is an urgent need to prepare and standardize the methodology of future trials targeting cNF.

OBJECTIVES

The objective was to develop a core outcome domain set suitable for all clinical trials targeting NF1-associated cNF.

METHODS

The validated approach of this work consisted of a three-phase methodology: (i) generating the domains [systematic literature review (SLR) and qualitative studies]; (ii) agreeing (three-round international e-Delphi consensus process and working groups); and (iii) voting.

RESULTS

(i) The SLR and the qualitative studies (three types of focus groups and a French e-survey with 234 participants) resulted in a preliminary list of 31 candidate items and their corresponding definitions. (ii) A total of 229 individuals from 29 countries participated in the first round of the e-Delphi process: 71 patients, relatives or representatives (31.0%), 130 healthcare professionals (HCPs, 56.8%) and 28 researchers, representatives of a drug regulatory authority, industry or pharmaceutical company representatives or journal editors (12.2%). The overall participation rate was 74%. After round 2, five candidate items were excluded. Between rounds 2 and 3, international workshops were held to better understand the disagreements among stakeholders. This phase led to the identification of 19 items as outcome subdomains. (iii) The items were fused to create four outcome domains ('clinical assessment', 'daily life impact', 'patient satisfaction' and 'perception of health') and prioritized. The seven items that did not reach consensus were marked for the research agenda. The final core outcome domain set reached 100% of the votes of the steering committee members.

CONCLUSIONS

Although numerous outcomes can be explored in studies related to cNF in NF1, the present study offers four outcome domains that should be reported in all trial studies, agreed on by international patients, relatives and representatives of patients; HCPs; researchers, representatives of drug regulatory authorities or pharmaceutical companies and journal editors. The next step will include the development of a set of core outcome measurement instruments to further standardize how these outcomes should be assessed.

Making good on the promise of genomics in healthcare: the NSW Health perspective

NSW Health is implementing genomics as a mainstream component of clinical care. The strategic, holistic approach is considering infrastructure, data governance and management, workforce, education, service planning and delivery. This work is generating insights about how to realise the promise of genomics in healthcare, highlighting the need for strong foundations, real-world application, accessibility and a focus on people using genomic information in clinical care.

Clinical and imaging modality factors impacting radiological interpretation of breast screening in young women with neurofibromatosis type 1

Young women with Neurofibromatosis type 1 (NF1) have a high risk of developing breast cancer and poorer survival following breast cancer diagnosis. International guidelines recommend commencing breast screening between 30 and 35 years; however, the optimal screening modality is unestablished, and previous reports suggest that breast imaging may be complicated by the presence of intramammary and cutaneous neurofibromas (cNFs). The aim of this study was to explore potential barriers to implementation of breast screening for young women with NF1.Twenty-seven women (30-47 years) with NF1 completed breast screening with breast MRI, mammogram and breast ultrasound. Nineteen probably benign/suspicious lesions were detected across 14 women. Despite the presence of breast cNFs, initial biopsy rate for participants with NF1 (37%), were comparable to a BRCA pathogenic variant (PV) cohort (25%) (P = 0.311). No cancers or intramammary neurofibromas were identified. Most participants (89%) returned for second round screening.The presence of cNF did not affect clinician confidence in 3D mammogram interpretation, although increasing breast density, frequently seen in young women, impeded confidence for 2D and 3D mammogram. Moderate or marked background parenchymal enhancement on MRI was higher in the NF1 cohort (70.4%) than BRCA PV carriers (47.3%), which is an independent risk factor for breast cancer.Breast MRI was the preferred mode of screening over mammogram, as the majority (85%) with NF1 demonstrated breast density (BI-RADS 3C/4D), which hinders mammogram interpretation. For those with high breast density and high cNF breast coverage, 3D rather than 2D mammogram is preferred, if MRI is unavailable.

Incorporating a polygenic risk score-triaged coronary calcium score into cardiovascular disease examinations to identify subclinical coronary artery disease (ESCALATE): Protocol for a prospective, nonrandomized implementation trial

BACKGROUND

Identifying and targeting established modifiable risk factors has been a successful strategy for reducing the burden of coronary artery disease (CAD) at the population-level. However, up to 1-in-4 patients who present with ST elevation myocardial infarction do so in the absence of such risk factors. Polygenic risk scores (PRS) have demonstrated an ability to improve risk prediction models independent of traditional risk factors and self-reported family history, but a pathway for implementation has yet to be clearly identified. The aim of this study is to examine the utility of a CAD PRS to identify individuals with subclinical CAD via a novel clinical pathway, triaging low or intermediate absolute risk individuals for noninvasive coronary imaging, and examining the impact on shared treatment decisions and participant experience.

TRIAL DESIGN

The ESCALATE study is a 12-month, prospective, multicenter implementation study incorporating PRS into otherwise standard primary care CVD risk assessments, to identify patients at increased lifetime CAD risk for noninvasive coronary imaging. One-thousand eligible participants aged 45 to 65 years old will enter the study, which applies PRS to those considered low or moderate 5-year absolute CVD risk and triages those with CAD PRS ≥80% for a coronary calcium scan. The primary outcome will be the identification of subclinical CAD, defined as a coronary artery calcium score (CACS) >0 Agatston units (AU). Multiple secondary outcomes will be assessed, including baseline CACS ≥100 AU or ≥75th age-/sex-matched percentile, the use and intensity of lipid- and blood pressure-lowering therapeutics, cholesterol and blood pressure levels, and health-related quality of life (HRQOL).

CONCLUSION

This novel trial will generate evidence on the ability of a PRS-triaged CACS to identify subclinical CAD, as well as subsequent differences in traditional risk factor medical management, pharmacotherapy utilization, and participant experience.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12622000436774. Trial was prospectively registered on March 18, 2022. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=383134.

Current and Emerging Imaging Techniques for Neurofibromatosis Type 1-Associated Cutaneous Neurofibromas

A consistent set of measurement techniques must be applied to reliably and reproducibly evaluate the efficacy of treatments for cutaneous neurofibromas (cNFs) in people with neurofibromatosis type 1 (NF1). cNFs are neurocutaneous tumors that are the most common tumor in people with NF1 and represent an area of unmet clinical need. This review presents the available data regarding approaches in use or development to identify, measure, and track cNFs, including calipers, digital imaging, and high-frequency ultrasound sonography. We also describe emerging technologies such as spatial frequency domain imaging and the application of imaging modalities such as optical coherence tomography that may enable the detection of early cNFs and prevention of tumor-associated morbidity.

Physical Activity Is Associated with Slower Cognitive Decline in Older Adults with Type 2 Diabetes

BACKGROUND

Physical activity is associated with slower cognitive decline in old age. Type 2 diabetes (T2d) is a risk factor for dementia and cognitive decline. Physical activity protects against several T2d complications. Yet, little is known about the contribution of physical activity to cognitive health among the elderly with T2d.

OBJECTIVES

To examine the association between physical activity and cognitive decline in older adults with T2d.

DESIGN

This is a prospective longitudinal study using data from the Israel Diabetes and Cognitive Decline (IDCD) study.

SETTING

ICDC study (N=1,213), is a population-based cohort of adults over the age of 65, diagnosed with type 2 diabetes, who were cognitively normal at baseline and followed up every 18 months.

PARTICIPANTS

Participants with at least one follow-up assessment who were in the same physical activity group consistently and had complete demographic data.

MEASUREMENTS

Physical activity was measured using Minnesota Leisure Time Activity Questionnaire, cognitive functioning was measured using a broad neuropsychological assessment measuring Executive Functioning, Attention/Working Memory, Semantic Categorization and Episodic Memory.

RESULTS

Participants were classified into physical activity groups based on self-reported physical activity at baseline and all follow ups: "active" - participation in recreational physical activity (n=286); "non-active"- the only physical activity was walking from place to place (n=93) and "sedentary" (n=19). Linear mixed effects models were applied to adjust for key demographic and cardiovascular risk factors. Participants were 72.4 (SD 4.6) years old, had 13.3 (SD 3.6) years of education, and 163 (41%) were female. In the fully adjusted model, compared to the non-active group the active group had significantly slower rate of decline in Global Cognition (p=0.005), Executive Functioning (p=.014), and Attention/Working Memory (p=.01). There were no significant group differences for Semantic Categorization (p=.17) and Episodic Memory (p=.88).

CONCLUSIONS

Among initially cognitively normal and independent older adults with T2d, a physically active lifestyle was associated with a slower rate of cognitive decline. Future research should examine whether promoting physical activity may prevent or delay onset of dementia in this high-risk population.

Characterization of health concerns in people with neurofibromatosis type 1

BACKGROUND

Neurofibromatosis 1 (NF1) is a common cancer predisposition syndrome. Affected individuals require lifelong surveillance and often suffer progressive disfigurement due to cutaneous neurofibromas. The aim of this research was to characterize health concerns and quality of life (QOL) in a population cohort.

METHODS

An online survey was completed by 68 adults and 32 parents of children with NF1, and 60 controls. The survey included the Skindex-29 QOL scale, 5D-itch scale, and additional health questions.

RESULTS

Frequency of itch was high in children (50%) and adults (69%), with most expressing interest in treatment for itch. The presence of itch and increased visibility of NF1 were predictors of poorer QoL. Many adults (53%) and parents (44%) desired access to treatment to improve cosmetic appearance. Muscle weakness/tiredness was also prevalent amongst (60-70%) adults and children with NF1. Two-thirds of adults with NF1 reported limited awareness of NF1 services and poor knowledge of surveillance, particularly breast screening in young women.

CONCLUSION

This study highlights the impact of NF1-related itch and visibility in adults and children with a need for cosmetic and itch treatment. The findings emphasize a need for strategies to promote awareness, and access to management and treatment of NF1 in adults.

Paediatric genomic testing: Navigating genomic reports for the general paediatrician

Monogenic rare disorders contribute significantly to paediatric morbidity and mortality, and elucidation of the underlying genetic cause may have benefits for patients, families and clinicians. Advances in genomic technology have enabled diagnostic yields of up to 50% in some paediatric cohorts. This has led to an increase in the uptake of genetic testing across paediatric disciplines. This can place an increased burden on paediatricians, who may now be responsible for interpreting and explaining test results to patients. However, genomic results can be complex, and sometimes inconclusive for the ordering paediatrician. Results may also cause uncertainty and anxiety for patients and their families. The paediatrician's genetic literacy and knowledge of genetic principles are therefore critical to inform discussions with families and guide ongoing patient care. Here, we present four hypothetical case vignettes where genomic testing is undertaken, and discuss possible results and their implications for paediatricians and families. We also provide a list of key terms for paediatricians.

Evaluating the model of offering expanded genetic carrier screening to high school students within the Sydney Jewish community

Programs offering reproductive genetic carrier screening (RGCS) to high school students within the Ashkenazi Jewish community in several countries including Canada and Australia have demonstrated high uptake and retention of educational messages over time. This study was undertaken to evaluate whether testing for an expanded number of conditions in a high school setting would impact the effectiveness of education. In this questionnaire-based study, genetic carrier testing for nine conditions was offered to 322 year 11 students from five high schools, with students attending a compulsory 1-h education session prior to voluntary testing. Comparison of pre- and post-education measures demonstrated a significant increase in knowledge, positive attitudes, and reduced concern immediately after the education session. Retention of knowledge, measures of positive attitude, and low concern over a 12-month period were significantly higher than baseline, although there was some reduction over time. In total, 77% of students exhibited informed choice regarding their intention to test. A significant increase in baseline knowledge scores and positive attitude was also demonstrated between our original 1995 evaluation (with testing for only one condition) and 2014 (testing for nine conditions) suggesting community awareness and attitudes to RGCS have increased. These findings validate the implementation of effective education programs as a key component of RGCS and are relevant as gene panels expand with the introduction of genomic technologies.

Standardized practices for RNA diagnostics using clinically accessible specimens reclassifies 75% of putative splicing variants

PURPOSE

Genetic variants causing aberrant premessenger RNA splicing are increasingly being recognized as causal variants in genetic disorders. In this study, we devise standardized practices for polymerase chain reaction (PCR)-based RNA diagnostics using clinically accessible specimens (blood, fibroblasts, urothelia, biopsy).

METHODS

A total of 74 families with diverse monogenic conditions (31% prenatal-congenital onset, 47% early childhood, and 22% teenage-adult onset) were triaged into PCR-based RNA testing, with comparative RNA sequencing for 19 cases.

RESULTS

Informative RNA assay data were obtained for 96% of cases, enabling variant reclassification for 75% variants that can be used for genetic counseling (71%), to inform clinical care (32%) and prenatal counseling (41%). Variant-associated mis-splicing was highly reproducible for 28 cases with samples from ≥2 affected individuals or heterozygotes and 10 cases with ≥2 biospecimens. PCR amplicons encompassing another segregated heterozygous variant was vital for clinical interpretation of 22 of 79 variants to phase RNA splicing events and discern complete from partial mis-splicing.

CONCLUSION

RNA diagnostics enabled provision of a genetic diagnosis for 64% of recruited cases. PCR-based RNA diagnostics has capacity to analyze 81.3% of clinically significant genes, with long amplicons providing an advantage over RNA sequencing to phase RNA splicing events. The Australasian Consortium for RNA Diagnostics (SpliceACORD) provide clinically-endorsed, standardized protocols and recommendations for interpreting RNA assay data.

Development and Preliminary Evaluation of a Quality-of-Life Questionnaire for Adults with Neurofibromatosis Type 1 (NF1-AdQOL)

BACKGROUND

Neurofibromatosis type 1 (NF1) is a variable and unpredictable multisystem genetic disorder which predisposes to medical complications, cognitive impairment and disfigurement, of all which can impact negatively upon the health related quality of life (HRQOL) of affected adults.

OBJECTIVES

To develop and validate a disease specific HRQOL adult questionnaire to evaluate effects of NF1 from the patient's viewpoint.

METHODS

The NF1 adult HRQOL questionnaire (NF1-AdQOL) was developed based on patient interviews (n=8), survey of clinicians and piloting of the questionnaire. Adults with NF1 (n=114, 18-40 years) were recruited from three Australian genetics clinics and completed the NF1-AdQOL, Skindex-29 and Short Form-36v2 (SF-36v2) questionnaires. An exploratory factor analysis of the NF1-AdQOL was conducted to assess construct validity. Convergent and discriminant validity of the NF1-AdQOL was determined by using the multi-trait multi-method with Skindex-29 and SF-36v2 scores.

RESULTS

Factor analysis indicated that 62.7% of the common variance could be explained by three factors labelled as 'emotions associated with cosmetic appearance' (12 items), 'social functioning and learning' (11 items) and 'physical symptoms' (8 items). NF1-AdQOL had good internal consistency (Cronbach's α = 0.96). Convergent validity was confirmed by moderate associations with similarly named scales of the Skindex-29 and SF-36v2. Results from all HRQOL questionnaires indicated overall healthy HRQOL for young adults with NF1.

CONCLUSIONS

NF1-AdQOL is a relatively valid, feasible and fairly easy to read tool to measure QOL in adults with NF1. Further evaluation is required to determine its test-retest reliability, responsiveness and validity in larger adult NF1 cohorts.

Measuring the Effect of Cutaneous Neurofibromas on Quality of Life in Neurofibromatosis Type 1

OBJECTIVE

In order to explore the use of Skindex scoring in patients with neurofibromatosis type 1 (NF1) across multiple clinical sites and inform design of additional quality of life measures, we analyzed correlations between Skindex, site, and clinical measures for 79 patients with NF1 from specialized clinics in Sydney, Australia (Royal North Shore Hospital [RNS]) and Minneapolis, Minnesota (University of Minnesota [UMN]).

METHODS

The relationship between clinical factors and Skindex scores were explored by clinic site and overall.

RESULTS

A total of 40 participants were recruited from RNS and 39 from UMN. Female sex, total number of cutaneous neurofibroma (cNF), and whether cNF were present on the face correlated highly with Skindex and not Riccardi scores. The UMN site had lower average scores, but these differences were almost entirely removed after adjusting for age, sex, facial cNF, and total cNF number.

CONCLUSIONS

The development of cNF in adolescence and adulthood in NF1 often leads to progressive disfigurement and discomfort and is among one of the most common reasons for patients to seek medical treatment. Skindex has been used to assess skin-related quality of life in NF1 previously but is not specific to NF1. These findings highlight the need for a low threshold for referral to dermatologists for all patients with NF1 regardless of the severity of disease. The finding that facial cNF and higher total number of cNF correlates with poorer skin-related quality of life may benefit design of more specific NF1 skin-related quality of life measures.

The psychological impact and experience of breast cancer screening in young women with an increased risk of breast cancer due to neurofibromatosis type 1

Women with neurofibromatosis type 1 (NF1) have an increased risk of developing early breast cancer with a poorer prognosis compared to the general population. Therefore, international management guidelines recommend regular screening in women with NF1 starting from 30 to 35 years. As the psychological impacts of breast cancer screening in other high-risk populations cannot be extended to women with NF1, due to increased incidence of cognitive and mental health issues, the psychological harms of breast screening in women with NF1 are unknown. Consequently, the aim of this study was to assess the psychological impact of breast cancer screening in women with NF1 attending an established risk management clinic. Twenty-eight women with NF1 (30–50 years) completed psychological well-being and patient experience questionnaires, administered across five time points, before and after their initial and second round annual breast screening visits. Preliminary findings demonstrated the screening regimen was well-tolerated, with most participants reporting high satisfaction with the screening process. Overall, no significant increase in psychological distress related to the breast screening process was identified, with mean cancer worry and anxiety scores decreasing over time. However, some women did experience negative aspects of screening and barriers to re-attendance at annual breast screening appointments. As some women with NF1 exhibited clinical levels of psychological distress prior to screening, efforts to identify those at risk and additional support to address concerns and expectations throughout the breast screening process may be beneficial.

Genetic counselors, patients', and carers' views on an Australian clinical genetics service information system

The Genetic Information System (GIS) is an Australian database of family genetic information. This health information technology system has been used by all 31 publicly operated clinical genetics services across New South Wales (NSW) and the Australian Capital Territory (ACT) for over a decade. As these services are separated geographically, the linkage engendered by the GIS facilitates the services to operate as a virtual state-wide service. This study aimed to explore the views of genetic counselors, patients, and carers on the use and storage of family genetic information in the GIS. Data were collected using audio-recorded semi-structured telephone interviews with genetic counselors experienced with using the GIS and focus groups with past patients/carers of the services. Using thematic analysis, four themes were identified from genetic counselor participant interviews (n = 12): (a) Shared information is valuable; (b) inconsistent data entry provides a challenge; (c) perceived need for the GIS to be current and integrated with other health systems; and (d) future challenges and strategies for the GIS. Three themes were identified following three focus groups with consumer participants (n = 14): (a) access to family genetic information provides a 'clearer picture'; (b) support, but caution, concerning use of information for relatives' health care; and (c) stewardship of family information. Genetic counselors and consumers identified similar advantages and privacy concerns regarding the sharing of family genetic information and all participants wanted patients/carers to be better informed about the GIS early in the genetic counseling process. Consumers were reassured by genetics health professionals' stewardship of their information, but surprised the GIS was not available nationally or for private geneticists or certain non-genetic specialists. These findings may inform further development of the GIS and other clinical genetic databases and lead to increased patient/carer knowledge through education and resource development.

Paediatric genomic testing: Navigating medicare rebatable genomic testing

Genomic testing for a genetic diagnosis is becoming standard of care for many children, especially those with a syndromal intellectual disability. While previously this type of specialised testing was performed mainly by clinical genetics teams, it is increasingly being 'mainstreamed' into standard paediatric care. With the introduction of a new Medicare rebate for genomic testing in May 2020, this type of testing is now available for paediatricians to order, in consultation with clinical genetics. Children must be aged less than 10 years with facial dysmorphism and multiple congenital abnormalities or have global developmental delay or moderate to severe intellectual disability. This rebate should increase the likelihood of a genetic diagnosis, with accompanying benefits for patient management, reproductive planning and diagnostic certainty. Similar to the introduction of chromosomal microarray into mainstream paediatrics, this genomic testing will increase the number of genetic diagnoses, however, will also yield more variants of uncertain significance, incidental findings, and negative results. This paper aims to guide paediatricians through the process of genomic testing, and represents the combined expertise of educators, clinical geneticists, paediatricians and genomic pathologists around Australia. Its purpose is to help paediatricians navigate choosing the right genomic test, consenting patients and understanding the possible outcomes of testing.

The knowledge base of a profession: the case of social work

Se afirma que las revistas desempeñan un papel importante para establecer la base de conocimientos de una profesión. Las profesiones utilizan también conocimientos procedentes de otras disciplinas y son, por tanto, de carácter interdisciplinar, al utilizar diversas formas de conocimiento. Tomando como ejemplo a los trabajadores sociales , el conocimiento empírico tal como aparece en las revistas resultó ser sólo una de sus fuentes de conocimiento. Esta profesión origina también literatura gris directamente relacionada con la experiencia en trabajos sociales. Dicha literatura gris permite la difusión de conocimientos sin base empírica, que son de utilidad para las profesiones aplicadas. El uso de conjunto del conocimiento empírico vía revistas y literatura gris requiere una integración por parte de archiveros y especialistas en información. Se plantea la cuestión de las actitudes de los profesionales prácticos frente al conocimiento empírico y de los académicos frente a la literatura gris. Se propone que el papel del archivero y del especialista en información consista en hacer que se acepte la información por su valor intrínseco.

First International Conference on RASopathies and Neurofibromatoses in Asia: Identification and advances of new therapeutics

The neurofibromatoses, which include neurofibromatosis type I (NF1), neurofibromatosis type II (NF2), and schwannomatosis, are a group of syndromes characterized by tumor growth in the nervous system. The RASopathies are a group of syndromes caused by germline mutations in genes that encode components of the RAS/mitogen-activated protein kinase (MAPK) pathway. The RASopathies include NF1, Noonan syndrome, Noonan syndrome with multiple lentigines, Costello syndrome, cardio-facio-cutaneous syndrome, Legius syndrome, capillary malformation arterio-venous malformation syndrome, and SYNGAP1 autism. Due to their common underlying pathogenetic etiology, all these syndromes have significant phenotypic overlap of which one common feature include a predisposition to tumors, which may be benign or malignant. Together as a group, they represent one of the most common multiple congenital anomaly syndromes estimating to affect approximately one in 1000 individuals worldwide. The subcontinent of India represents one of the largest populations in the world, yet remains underserved from an aspect of clinical genetics services. In an effort to bridge this gap, the First International Conference on RASopathies and Neurofibromatoses in Asia: Identification and Advances of New Therapeutics was held in Kochi, Kerala, India. These proceedings chronicle this timely and topical international symposium directed at discussing the best practices and therapies for individuals with neurofibromatoses and RASopathies.

Uptake of health monitoring and disease self-management in Australian adults with neurofibromatosis type 1: strategies to improve care

Lifelong health monitoring is recommended in neurofibromatosis type 1 (NF1) because of the progressive and unpredictable range of disabling and potentially life-threatening symptoms that arise. In Australia, strategies for NF1 health surveillance are less well developed for adults than they are for children, resulting in inequalities between pediatric and adult care. The aims of this study were to determine the uptake of health monitoring and capacity of adults with NF1 to self-manage their health. Australian adults with NF1 (n = 94, 18-40 years) participated in a semi-structured interview. Almost half reported no regular health monitoring. Thematic analysis of interviews identified four main themes as to why: (i) did not know where to seek care, (ii) unaware of the need for regular monitoring, (iii) futility of health monitoring as nothing can be done for NF1, and (iv) feeling healthy, therefore monitoring unnecessary. Overall, there were low levels of patient activation, indicating that adults with NF1 lacked knowledge and confidence to manage their health and health care. Findings are discussed in the context of service provision for adults with NF1 in New South Wales, Australia.

Ashkenazi Jewish population screening for Tay-Sachs disease: the international and Australian experience

Internationally, Tay-Sachs disease (TSD) preconception screening of Ashkenazi Jewish (AJ) individuals and couples has led to effective primary prevention of TSD. In Australia, adolescent preconception genetic screening programs operate mainly in Jewish community high schools. These existing programs offer an effective means of primary prevention of TSD, are cost effective and safe. However, in the broader Australian community TSD screening is not systematically performed and cases still occur in unscreened AJ individuals. In order to improve the effectiveness of Australian screening, there is a need for definitive guidelines for healthcare professionals to facilitate extension of the proven benefits of preconception TSD screening to all AJ individuals at risk. We performed a systematic review of the relevant literature relating to AJ pre-conception and antenatal screening for TSD. The evidence was assessed using an established National Health and Medical Research Council evidence grading system. Evaluations of efficacy of TSD screening programs design and execution, cost-benefit and cost-utility health economic evaluation, and population outcomes were undertaken. The results have been used to propose a model for universal AJ TSD preconception and antenatal screening for the primary care setting.

α-Actinin-3 deficiency is associated with reduced bone mass in human and mouse

Bone mineral density (BMD) is a complex trait that is the single best predictor of the risk of osteoporotic fractures. Candidate gene and genome-wide association studies have identified genetic variations in approximately 30 genetic loci associated with BMD variation in humans. α-Actinin-3 (ACTN3) is highly expressed in fast skeletal muscle fibres. There is a common null-polymorphism R577X in human ACTN3 that results in complete deficiency of the α-actinin-3 protein in approximately 20% of Eurasians. Absence of α-actinin-3 does not cause any disease phenotypes in muscle because of compensation by α-actinin-2. However, α-actinin-3 deficiency has been shown to be detrimental to athletic sprint/power performance. In this report we reveal additional functions for α-actinin-3 in bone. α-Actinin-3 but not α-actinin-2 is expressed in osteoblasts. The Actn3(-/-) mouse displays significantly reduced bone mass, with reduced cortical bone volume (-14%) and trabecular number (-61%) seen by microCT. Dynamic histomorphometry indicated this was due to a reduction in bone formation. In a cohort of postmenopausal Australian women, ACTN3 577XX genotype was associated with lower BMD in an additive genetic model, with the R577X genotype contributing 1.1% of the variance in BMD. Microarray analysis of cultured osteoprogenitors from Actn3(-/-) mice showed alterations in expression of several genes regulating bone mass and osteoblast/osteoclast activity, including Enpp1, Opg and Wnt7b. Our studies suggest that ACTN3 likely contributes to the regulation of bone mass through alterations in bone turnover. Given the high frequency of R577X in the general population, the potential role of ACTN3 R577X as a factor influencing variations in BMD in elderly humans warrants further study.

A gene for speed: the emerging role of alpha-actinin-3 in muscle metabolism

A common polymorphism (R577X) in the ACTN3 gene results in complete deficiency of alpha-actinin-3 protein in approximately 16% of humans worldwide. The presence of alpha-actinin-3 protein is associated with improved sprint/power performance in athletes and the general population. Despite this, there is evidence that the null genotype XX has been acted on by recent positive selection, likely due to its emerging role in the regulation of muscle metabolism. alpha-Actinin-3 deficiency reduces the activity of glycogen phosphorylase and results in a fundamental shift toward more oxidative pathways of energy utilization.

Loss of ACTN3 gene function alters mouse muscle metabolism and shows evidence of positive selection in humans

More than a billion humans worldwide are predicted to be completely deficient in the fast skeletal muscle fiber protein alpha-actinin-3 owing to homozygosity for a premature stop codon polymorphism, R577X, in the ACTN3 gene. The R577X polymorphism is associated with elite athlete status and human muscle performance, suggesting that alpha-actinin-3 deficiency influences the function of fast muscle fibers. Here we show that loss of alpha-actinin-3 expression in a knockout mouse model results in a shift in muscle metabolism toward the more efficient aerobic pathway and an increase in intrinsic endurance performance. In addition, we demonstrate that the genomic region surrounding the 577X null allele shows low levels of genetic variation and recombination in individuals of European and East Asian descent, consistent with strong, recent positive selection. We propose that the 577X allele has been positively selected in some human populations owing to its effect on skeletal muscle metabolism.

Location and type of mutation in the LIS1 gene do not predict phenotypic severity

BACKGROUND

Lissencephaly is a neuronal migration disorder leading to absent or reduced gyration and a broadened but poorly organized cortex. The most common form of lissencephaly is isolated, referred as classic or type 1 lissencephaly. Type 1 lissencephaly is mostly associated with a heterozygous deletion of the entire LIS1 gene, whereas intragenic heterozygous LIS1 mutations or hemizygous DCX mutations in males are less common.

METHODS

Eighteen unrelated patients with type 1 lissencephaly were clinically and genetically assessed. In addition, patients with subcortical band heterotopia (n = 1) or lissencephaly with cerebellar hypoplasia (n = 2) were included.

RESULTS

Fourteen new and seven previously described LIS1 mutations were identified. We observed nine truncating mutations (nonsense, n = 2; frameshift, n = 7), six splice site mutations, five missense mutations, and one in-frame deletion. Somatic mosaicism was assumed in three patients with partial subcortical band heterotopia in the occipital-parietal lobes or mild pachygyria. We report three mutations in exon 11, including a frameshift which extends the LIS1 protein, leading to type 1 lissencephaly and illustrating the functional importance of the WD domains at the C terminus. Furthermore, we present two patients with novel LIS1 mutations in exon 10 associated with lissencephaly with cerebellar hypoplasia type a.

CONCLUSION

In contrast to previous reports, our data suggest that neither type nor position of intragenic mutations in the LIS1 gene allows an unambiguous prediction of the phenotypic severity. Furthermore, patients presenting with mild cerebral malformations such as subcortical band heterotopia or cerebellar hypoplasia should be considered for genetic analysis of the LIS1 gene.

Nanophthalmos in a Melanesian population

PURPOSE

To characterize the ophthalmic features and causes of visual loss in a cohort of Melanesians living in New Caledonia with nanophthalmos.

METHODS

In this observational study, axial length, visual acuity (VA), cycloplegic autorefraction were assessed and dilated fundus examination was performed. Visual impairment was defined as VA<6/12 in the better eye, hypermetropia as >+1.0 dioptre (D), astigmatism as >or=1.0 D and anisometropia as >or=1.0 D difference between both eyes. Unilateral amblyopia was defined as at least a two-line difference in VA between both eyes and bilateral amblyopia as VA<6/12 in both eyes which was not adequately explained by refractive error and macular folds.

RESULTS

Seventeen community-dwelling participants (aged 1.1-45.3 years) with short axial length (range from 16.1 to 21.6 mm) were identified. Of the 17 subjects, 14 were found to have crowded optic discs, three with papillomacular folds, three with a papillomacular band and three with macular radial folds. Further, all subjects demonstrated bilateral hypermetropia (range from +1.3 D to +15.1 D). A high proportion of subjects had astigmatism (12) and anisometropia (nine) in at least one eye. Visual impairment was found in nine subjects: five bilateral and four unilateral. Causes of visual impairment included amblyopia (seven), ametropia (seven) and macular folds (two). Amblyopia was attributed to several factors, including hypermetropia, anisometropia, astigmatism and esotropia.

CONCLUSIONS

In this sample of Melanesians with nanophthalmos, a spectrum of ophthalmic features that was consistent with intraocular crowding was found. Over half of the subjects were visually impaired, mostly due to amblyopia and ametropia. Further characterization of the underlying genetic cause of nanophthalmos in this cohort will be the focus of future studies.

Multicystic dysplastic kidney and variable phenotype in a family with a novel deletion mutation of PAX2

The renal coloboma syndrome (OMIM 120330) is caused by mutations in the PAX2 gene. Typical findings in these patients include renal hypoplasia, renal insufficiency, vesicoureteric reflux, and optic disc coloboma. A family with a novel heterozygous 10-bp deletion in exon 2 of the PAX2 gene leading to a truncating mutation and variable phenotype across three generations is reported. The first presentation of multicystic dysplastic kidney in this syndrome is reported. The possibility that abnormal PAX2 protein in this case may cause a dominant negative effect also is discussed. The finding of multicystic dysplastic kidney in renal coloboma syndrome could suggest that PAX2 may play a role in early ureteric obstruction and subsequent renal maldevelopment.

Chronic food restriction increases D-1 dopamine receptor agonist-induced phosphorylation of extracellular signal-regulated kinase 1/2 and cyclic AMP response element-binding protein in caudate-putamen and nucleus accumbens

Results of behavioral and c-fos immunohistochemical studies have suggested that chronic food restriction and maintenance of animals at 75-80% of free-feeding body weight may increase d-1 dopamine (DA) receptor function. The purpose of the present study was to determine whether D-1 DA receptor binding and/or mitogen-activated protein kinase (MAPK) signaling in caudate-putamen (CPu) and nucleus accumbens (NAc) are increased in food-restricted subjects. In the first experiment, saturation binding of the D-1 DA receptor antagonist [3H]SCH-23390 indicated no difference between food-restricted and ad libitum fed rats with regard to density or affinity of d-1 binding sites in CPu or NAc. In the second experiment, activation of extracellular signal-regulated kinases (ERK1/2) and cyclic AMP response element-binding protein (CREB) by i.c.v. injection of the D-1 DA receptor agonist SKF-82958 (20 microg) were markedly greater in food-restricted than ad libitum fed rats. Given a prior finding that SKF-82958 does not differentially stimulate adenylyl cyclase in CPu or NAc of food-restricted versus ad libitum fed subjects, the present results suggest that increased D-1 DA receptor-mediated ERK1/2 MAP kinase signaling may mediate the enhanced downstream activation of CREB, c-fos, and behavioral responses in food-restricted subjects. It is of interest that food restriction also increased the activation of c-Jun N-terminal protein kinase/stress-activated protein kinase, but this effect was no greater in rats injected with SKF-82958 than in those injected with saline vehicle. This represents additional evidence of increased striatal cell signaling in food-restricted subjects, presumably in response to the i.c.v. injection procedure, although the underlying receptor mechanisms remain to be determined. There were no differences between feeding groups in protein levels of the major phosphatases, MKP-2 and PP1. The upregulation of striatal MAP kinase signaling in food-restricted animals may adaptively serve to facilitate associative learning but, at the same time, increase vulnerability to the rewarding and addictive properties of abused drugs.

Evidence of increased dopamine receptor signaling in food-restricted rats

It is well established that chronic food restriction enhances sensitivity to the rewarding and motor-activating effects of abused drugs. However, neuroadaptations underlying these behavioral effects have not been characterized. The purpose of the present study was to explore the possibility that food restriction produces increased dopamine (DA) receptor function that is evident in behavior, signal transduction, and immediate early gene expression. In the first two experiments, rats received intracerebroventricular (i.c.v.) injections of the D1 DA receptor agonist SKF-82958, and the D2/3 DA receptor agonist quinpirole. Both agonists produced greater motor-activating effects in food-restricted than ad libitum-fed rats. In addition, Fos-immunostaining induced by SKF-82958 in caudate-putamen (CPu) and nucleus accumbens (Nac) was greater in food-restricted than ad libitum-fed rats, as was staining induced by quinpirole in globus pallidus and ventral pallidum. In the next two experiments, neuronal membranes prepared from CPu and Nac were exposed to SKF-82958 and quinpirole. Despite the documented involvement of cyclic AMP (cAMP) signaling in D1 DA receptor-mediated c-fos induction, stimulation of adenylyl cyclase (AC) activity by SKF-82958 in CPu and Nac did not differ between groups. Food restriction did, however, decrease AC stimulation by the direct enzyme stimulant, forskolin, but not NaF or MnCl(2), suggesting a shift in AC expression to a less catalytically efficient isoform. Finally, food restriction increased quinpirole-stimulated [(35)S]guanosine triphosphate-gammaS binding in CPu, suggesting that increased functional coupling between D2 DA receptors and G(i) may account for the augmented behavioral and pallidal c-Fos responses to quinpirole. Results of this study support the hypothesis that food restriction leads to neuroadaptations at the level of postsynaptic D1 and D2 receptor-bearing cells which, in turn, mediate augmented behavioral and transcriptional responses to DA. The signaling pathways mediating these augmented responses remain to be fully elucidated.

ProSAAS processing in mouse brain and pituitary

ProSAAS is a newly discovered protein with a neuroendocrine distribution generally similar to that of prohormone convertase 1 (PC1), a peptide-processing endopeptidase. Several proSAAS-derived peptides were previously identified in the brain and pituitary of the Cpe(fat)/Cpe(fat) mouse based on the accumulation of C-terminally extended peptides due to the absence of enzymatically active carboxypeptidase E, a peptide-processing exopeptidase. In the present study, antisera against different regions of proSAAS were used to develop radioimmunoassays and examine the processing profile of proSAAS in wild type and Cpe(fat)/Cpe(fat) mouse tissues following gel filtration and reverse phase high performance liquid chromatography. In wild type mouse brain and pituitary, the majority of proSAAS is processed into smaller peptides. These proSAAS-derived peptides elute from the reverse-phase column in the same positions as synthetic peptides that correspond to little SAAS, PEN, and big LEN. Mass spectrometry revealed the presence of peptides with the expected molecular masses of little SAAS and big LEN in the fractions containing immunoreactive peptides. The processing of proSAAS is slightly impaired in Cpe(fat)/Cpe(fat) mice, relative to wild-type mice, leading to the accumulation of partially processed peptides. One of these peptides, the C-terminally extended form of PEN, is known to inhibit PC1 activity and this could account for the reduction in enzymatically active PC1 seen in Cpe(fat)/Cpe(fat) mice. The observation that little SAAS and big LEN are the major forms of these peptides produced in mouse brain and pituitary raises the possibility that these peptides function as neurotransmitters or hormones.

Impaired prohormone convertases in Cpe(fat)/Cpe(fat) mice

A spontaneous point mutation in the coding region of the carboxypeptidase E (CPE) gene results in a loss of CPE activity that correlates with the development of late onset obesity (Nagert, J. K., Fricker, L. D., Varlamov, O., Nishina, P. M., Rouille, Y., Steiner, D. F., Carroll, R. J., Paigen, B. J., and Leiter, E. H. (1995) Nat. Genet. 10, 135-142). Examination of the level of neuropeptides in these mice showed a decrease in mature bioactive peptides as a result of a decrease in both carboxypeptidase and prohormone convertase activities. A defect in CPE is not expected to affect endoproteolytic processing. In this report we have addressed the mechanism of this unexpected finding by directly examining the expression of the major precursor processing endoproteases, prohormone convertases PC1 and PC2 in Cpe(fat) mice. We found that the levels of PC1 and PC2 are differentially altered in a number of brain regions and in the pituitary. Since these enzymes have been implicated in the generation of neuroendocrine peptides (dynorphin A-17, beta-endorphin, and alpha- melanocyte-stimulating hormone) involved in the control of feeding behavior and body weight, we compared the levels of these peptides in Cpe(fat) and wild type animals. We found a marked increase in the level of dynorphin A-17, a decrease in the level of alpha-melanocyte-stimulating hormone, and an alteration in the level of C-terminally processed beta-endorphin. These results suggest that the impairment in the level of these and other peptides involved in body weight regulation is mainly due to an alteration in carboxypeptidase and prohormone convertase activities and that this may lead to the development of obesity in these animals.

Defective prodynorphin processing in mice lacking prohormone convertase PC2

Prodynorphin, a multifunctional precursor of several important opioid peptides, is expressed widely in the CNS. It is processed at specific single and paired basic sites to generate various biologically active products. Among the prohormone convertases (PCs), PC1 and PC2 are expressed widely in neuroendocrine tissues and have been proposed to be the major convertases involved in the biosynthesis of hormonal and neural peptides. In this study we have examined the physiological involvement of PC2 in the generation of dynorphin (Dyn) peptides in mice lacking active PC2 as a result of gene disruption. Enzymological and immunological assays were used to confirm the absence of active PC2 in these mice. The processing profiles of Dyn peptides extracted from brains of these mice reveal a complete lack of Dyn A-8 and a substantial reduction in the levels of Dyn A-17 and Dyn B-13. Thus, PC2 appears to be involved in monobasic processing, leading to the generation of Dyn A-8, Dyn A-17, and Dyn B-13 from prodynorphin under physiological conditions. Brains of heterozygous mice exhibit only half the PC2 activity of wild-type mice; however, the levels of Dyn peptides in these mice are similar to those of wild-type mice, suggesting that a 50% reduction in PC2 activity is not sufficient to significantly reduce prodynorphin processing. The disruption of the PC2 gene does not lead to compensatory up-regulation in the levels of other convertases with similar substrate specificity because we find no significant changes in the levels of PC1, PC5/PC6, or furin in these mice as compared with wild-type mice. Taken together, these results support a critical role for PC2 in the generation of Dyn peptides.

Specificity of the dynorphin-processing endoprotease: comparison with prohormone convertases

The cleavage specificity of a monobasic processing dynorphin converting endoprotease is examined with a series of quench fluorescent peptide substrates and compared with the cleavage specificity of prohormone convertases. A dynorphin B-29-derived peptide, Abz-Arg-Arg-Gln-Phe-Lys-Val-Val-Thr-Arg-Ser-Glneddnp (where Abz is o-aminobenzoyl and eddnp is ethylenediamine 2,4-dinitrophenyl), that contains both dibasic and monobasic cleavage sites is efficiently cleaved by the dynorphin converting enzyme and not cleaved by two propeptide processing enzymes, furin and prohormone convertase 1. A shorter prorenin-related peptide, Dnp-Arg-Met-Ala-Arg-Leu-Thr-Leu-eddnp, that contains a monobasic cleavage site is cleaved by the dynorphin converting enzyme and prohormone convertase 1 and not by furin. Substitution of the P1' position by Ala moderately affects cleavage by the dynorphin-processing enzyme and prohormone convertase 1. It is interesting that this substitution results in efficient cleavage by furin. The site of cleavage, as determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry, is N-terminal to the Arg at the P1 position for the dynorphin converting enzyme and C-terminal to the Arg at the P1 position for furin and prohormone convertase 1. Peptides with additional basic residues at the P2 and at P4 positions also serve as substrates for the dynorphin converting enzyme. This enzyme cleaves shorter peptide substrates with significantly lower efficiency as compared with the longer peptide substrates, suggesting that the dynorphin converting enzyme prefers longer peptides that contain monobasic processing sites as substrates. Taken together, these results suggest that the cleavage specificity of the dynorphin converting enzyme is distinct but related to the cleavage specificity of the prohormone convertases and that multiple enzymes could be involved in the processing of peptide hormones and neuropeptides at monobasic and dibasic sites.

Dynorphin A processing enzyme: tissue distribution, isolation, and characterization

Limited proteolysis of the dynorphin precursor (prodynorphin) at dibasic and monobasic processing sites results in the generation of bioactive dynorphins. In the brain and neurointermediate lobe of the pituitary, prodynorphin is processed to produce alpha and beta neo endorphins, dynorphins (Dyn) A-17 and Dyn A-8, Dyn B-13, and leucine-enkephalin. The formation of Dyn A-8 from Dyn A-17 requires a monobasic cleavage between Ile and Arg. We have identified an enzymatic activity capable of processing at this monobasic site in the rat brain and neurointermediate lobe of the bovine pituitary; this enzyme is designated "dynorphin A-17 processing enzyme." In the rat brain and neurointermediate lobe, a majority of the Dyn A processing enzyme activity is membrane-associated and can be released by treatment with 1% Triton X-100. This enzyme has been purified to apparent homogeneity from the membrane extract of the neurointermediate lobe using preparative iso-electrofocussing in a granulated gel pH 3.5 to 10, FPLC using anion exchange chromatography, and non-denaturing electrophoresis. The Dyn A processing enzyme exhibits a pI of about 5.8 and a molecular mass of about 65 kDa under reducing conditions. The Dyn A processing enzyme is a metalloprotease and has a neutral pH optimum. It exhibits substantial sensitivity to metal chelating agents and thiol agents suggesting that this enzyme is a thiol-sensitive metalloprotease. Specific inhibitors of other metallopeptidases such as enkephalinase [EC 3.4.24.11], the enkephalin generating neutral endopeptidase [EC 3.4.24.15], or NRD convertase do not inhibit the Dyn A processing enzyme activity. In contrast, specific inhibitors of angiotensin converting enzyme inhibit the activity. The purified enzyme is able to process a number of neuropeptides at both monobasic and dibasic sites. These characteristics are consistent with a role for the Dyn A processing enzyme in the processing of Dyn A-17 and other neuropeptides in the brain.

Bax cleavage is mediated by calpain during drug-induced apoptosis

The anti-apoptotic molecule Bcl-2 is located in the mitochondrial and endoplasmic reticulum membranes as well as the nuclear envelope. Although its location has not been as rigorously defined, the pro-apoptotic molecule Bax appears to be mainly a cytosolic protein which translocates to the mitochondria upon induction of apoptosis. Here we identify a protease activity in mitochondria-enriched membrane fractions from HL-60 cells capable of cleaving Bax which is absent from the cytosolic fraction. Bax protease activity is blocked in vitro by cysteine protease inhibitors including E-64 which distinguishes it from all known caspases and granzyme B, both of which are involved in apoptosis. Protease activity is also blocked by inhibitors against the calcium-activated neutral cysteine endopeptidase calpain. Partial purification of the Bax protease activity from HL-60 cell membrane fractions by column chromatography revealed that a calpain-like activity was the protease responsible for Bax cleavage. In addition, purified calpain enzymes cleaved Bax in a calcium-dependent manner. Pretreatment of HL-60 cells with the specific calpain inhibitor calpeptin effectively blocked both drug-induced Bax cleavage and calpain activation, but not PARP cleavage or cell death. These results suggest that calpains and caspases are activated during drug-induced apoptosis and that calpains, along with caspases, may be involved in modulating cell death by acting selectively on cellular substrates.

Instability of the amyloidogenic cystatin C variant of hereditary cerebral hemorrhage with amyloidosis, Icelandic type

A cystatin C variant with L68Q substitution and a truncation of 10 NH2-terminal residues is the major constituent of the amyloid deposited in the cerebral vasculature of patients with the Icelandic form of hereditary cerebral hemorrhage with amyloidosis (HCHWA-I). Variant and wild type cystatin C production, processing, secretion, and clearance were studied in human cell lines stably overexpressing the cystatin C genes. Immunoblot and mass spectrometry analyses demonstrated monomeric cystatin C in cell homogenates and culture media. While cystatin C formed concentration-dependent dimers, the HCHWA-I variant dimerized at lower concentrations than the wild type protein. Amino-terminal sequence analysis revealed that the variant and normal proteins produced and secreted are the full-length cystatin C. Pulse-chase experiments demonstrated similar levels of normal and variant cystatin C production and secretion. However, the secreted variant cystatin C exhibited an increased susceptibility to a serine protease in conditioned media and in human cerebrospinal fluid, explaining its depletion from the cerebrospinal fluid of HCHWA-I patients. Thus, the amino acid substitution may induce unstable cystatin C with intact inhibitory activity and predisposition to self-aggregation and amyloid fibril formation.

Effects of an intrahypothalamic injection of antisense oligonucleotides for preproenkephalin mRNA in female rats: evidence for opioid involvement in lordosis reflex

Previous studies in female rats have shown that estrogen increases preproenkephalin (PPE) mRNA levels in the ventrolateral part of the ventromedial nucleus of the hypothalamus (VMHVL), an area implicated in the modulation of sexual behavior. In order to assess the physiological role of hypothalamic opioid expression in lordosis reflex 16-mer oligodeoxynucleotide (ODN) directed towards the PPE mRNA were acutely microinjected above the VMH of estradiol-primed ovariectomized rats. Estradiol-induced lordosis behavior was observed in response to a stud male 2 days thereafter. Antisense (without or with 4 mismatches) ODN injections near the VMHVL resulted in a significant reduction in lordosis quotient compared to control (reverse sense) ODN treatment or to antisense ODN injections targeted anterior or posterior to the VMHVL. In contrast, locomotor activity of these animals in the open-field test was not affected by ODN treatments. Enkephalin immunoreactive levels were determined by radioimmunoassay in the preoptic area, a major terminal field of the VMHVL. Estradiol-induced enkephalin levels were greatly reduced in antisense-treated groups. Using the in situ hybridization technique, PPE mRNA levels in the VMHVL were also determined. A 1.5-2-fold increase in PPE mRNA levels was observed in estradiol-treated rats compared to ovariectomized rats as previously described. This increase in PPE mRNA levels was not affected by ODN treatment, suggesting that the reduction of enkephalin expression was mainly due to physical blockade of PPE mRNA translation and not to its degradation. Taken together, these data further support the behavioral role of PPE expressing VMHVL neurons. They also highlight the in vivo potency of acute administration of antisense phosphorothioate ODNs in blocking neuronal target gene expression.

Chronic food restriction and streptozotocin-induced diabetes differentially alter prodynorphin mRNA levels in rat brain regions

It was previously reported that chronic food restriction and streptozotocin-induced diabetes lead to brain region-specific changes in levels of Prodyn-derived peptides. These changes parallel behavioral adaptations that are reversed by opioid antagonists. In the present study, effects of food restriction and diabetes on Prodyn gene expression were measured in rat brain regions using a quantitative solution hybridization mRNA assay. Picogram amounts of Prodyn mRNA were determined in extracts of five brain regions. The highest density of Prodyn mRNA was observed in extracts of nucleus accumbens (4.68 pg/microg total RNA), bed nucleus of the stria terminalis (4.18 pg/microg), and in caudate nucleus (3.51 pg/microg). Lower levels were observed in the lateral hypothalamus (1.87 pg/microg) and central nucleus of the amygdala (1.22 pg/microg). Food restriction and diabetes both markedly increased the levels of Prodyn mRNA in the central amygdala (163% and 93%, respectively). Levels in the lateral hypothalamus were also increased (35% and 29%, respectively), though only the food-restriction effect was statistically significant. Neither treatment altered prodynorphin mRNA levels in the caudate nucleus, nucleus accumbens or bed nucleus of the stria terminalis. These results suggest that dynorphin neurons in central amygdala and lateral hypothalamus may be involved in behavioral or physiological adaptations to sustained metabolic need.

Curve-shift analysis of self-stimulation in food-restricted rats: relationship between daily meal, plasma corticosterone and reward sensitization

Chronic food restriction lowers the threshold for lateral hypothalamic electrical self-stimulation (LHSS). This effect has previously been interpreted to reflect a sensitization of reward. In the present study a curve-shift method was used to explicitly differentiate effects of food restriction on brain stimulation rewarding efficacy and performance. Food restriction consistently shifted rate-frequency curves to the left, lowering the M-50 and Theta-0 parameters of rewarding efficacy. Asymptotic rates of reinforcement and slopes of rate-frequency functions were unaffected, confirming that food restriction does not facilitate LHSS by enhancing performance. In this and previous studies, LHSS in food-restricted rats was measured in the period immediately preceding the daily meal when hunger (i.e., period since last meal) and plasma corticosterone are at peak levels. In the light of evidence that corticosterone may regulate sensitivity of the mesolimbic dopamine pathway and account for the sensitizing effect of stress on psychomotor effects of opiates and stimulants, LHSS and corticosterone were measured in the immediate pre-and post-meal periods. While all food-restricted rats displayed elevated corticosterone levels in the pre-meal period and generally displayed a decline to control levels in the post-meal period, the sensitization of reward was not reversed in the post-meal period. These results indicate that chronic food restriction produces a sensitization of reward that does not depend upon the acute state of hunger that precedes the daily meal and does not vary with dynamic changes in plasma corticosterone level.

Effects of streptozotocin-induced diabetes on prodynorphin-derived peptides in rat brain regions

Pharmacological studies suggest that diabetes produces changes in the brain opioid system, affecting several behavioral functions including analgesia, feeding and self-stimulation. Previous investigations of opioid receptor binding have failed to explain the unusual opioid pharmacology of the diabetic animal. In the present study, the effects of streptozotocin-induced diabetes on levels of three immunoreactive (ir)-prodynorphin-derived peptides, ir-dynorphin A1-17 (A1-17), ir-dynorphin A1-8 (A1-8) and ir-dynorphin B1-13 (B1-13), were determined in eleven brain regions known to be involved in appetite, taste and reward. Diabetes was found to increase levels of A1-17 in the ventromedial and dorsomedial hypothalamic nuclei (+60% and +25%, respectively) and levels of A1-8 in the dorsomedial and lateral hypothalamus (+45% and +35%, respectively). The possible significance of these results is discussed in relation to (i) diabetic hyperphagia, (ii) medial hypothalamic transduction of circulating insulin levels, and (iii) the potentiation of reward by metabolic need states.

Effects of chronic food restriction on prodynorphin-derived peptides in rat brain regions

Chronic food restriction produces a variety of physiological and behavioral adaptations including a potentiation of the reinforcing effect of food, drugs and lateral hypothalamic electrical stimulation. Previous work in this laboratory has revealed that the lowering of self-stimulation threshold by food restriction is reduced by mu- and kappa-selective opioid antagonists. In the present study, the effect of chronic food restriction on levels of three prodynorphin-derived peptides, namely dynorphin A1-17 (A1-17), dynorphin A1-8 (A1-8) and dynorphin B1-13 (B1-13) were measured in eleven brain regions known to be involved in appetite, taste and reward. Food restriction increased levels of A1-17 in dorsal medial (+19.6%), ventral medial (+24.2%) and medial preoptic (+82.9%) hypothalamic areas. Levels of A1-17 decreased in the central nucleus of the amygdala (-35.1%). Food restriction increased levels of A1-8 in nucleus accumbens (+34.4%), bed nucleus of the stria terminalis (+24.5%) and lateral hypothalamus (+41.9%). Food restriction had no effect on levels of B1-13. A1-17 is highly kappa-preferring and the brain regions in which levels increased all have a high ratio of kappa: mu and delta receptors. A1-8 is less discriminating among opioid receptor types and the brain regions in which levels increased have a low ratio of kappa: mu and delta receptors. The present results suggest that food restriction alters posttranslational processing within the dynorphin A domain of the prodynorphin precursor, possibly leading to a change in the balance between kappa and non-kappa opioid receptor stimulation in specific brain regions.

The Arab uprising and Jewish migration patterns in Judea, Samaria and Gaza

"The current study analyzes Jewish migration patterns in Judea, Samaria and Gaza in relation to issues identified by previous studies to be related to migration in general and to Jewish migration specifically, namely, economic, physical security and ideological-religious factors." The focus is on the impact of the Arab uprising, or intifada, that has occurred since 1987. The author concludes that economic factors tending to encourage Jews to leave the occupied territories are balanced by political factors influencing Jews to move to those areas. (SUMMARY IN FRE)

Patterns of migration from Europe to Israel: Jewish migration, 1919-1984

"An analysis was made from data published by Israel's Central Bureau of Statistics (1985) on Jewish immigrants by period of immigration and country of birth. Five periods of immigration are included in the study: 1919-May 14, 1948, May 15, 1948-1960, 1961-1964, 1965-1971, 1972-1979, and 1980-1984." The results show that although immigration from Europe has played a major role during this period of time, it has decreased significantly in the 1980s "as a result of several factors--restrictions on the number of Jews permitted to leave the USSR, the establishment of the United States and Canada as immigration destinations preferable to Israel, and the economic recession in Israel...." (SUMMARY IN FRE)