Effects of psychosocial work factors on preterm birth: systematic review and meta-analysis.

OBJECTIVES: Preterm birth is one of the global public health issues that result in high rates of infant mortality and long-term health complications. We sought to explore the association between psychosocial work factors and preterm birth. STUDY DESIGN: Systematic review and meta-analysis. METHODS: This systematic review and meta-analysis searched relevant literature from electronic databases to explore the association between psychosocial work factors and preterm birth. The methodological quality of the included studies was evaluated through the Joanna Briggs Institute's critical appraisal method. We performed a meta-analysis using a random-effects model to combine odds ratios (ORs) from studies with similar definitions of exposure and outcome. The quality of the evidence was evaluated using the GRADE (Grade of recommendation, Assessment, development, and Evaluation) method to assess. RESULTS: Ten studies were included, with a total of 92,815 participants. Moderate evidence indicated a positive association between high psychosocial job strain and preterm birth. The result from the meta-analysis supported the statistical significance of this relationship (OR 1.32 [95% CI (1.22-1.44)]). CONCLUSIONS: Pregnant women who experience high levels of psychosocial job strain are more likely to give birth prematurely. In order to decrease this risk, employers should prioritise creating supportive work environments, government bodies should enact protective policies and regulations, and clinicians should give advice to pregnant working women. Pregnant women should be aware of the risk of preterm birth from psychosocial work factors.

Management of encounters related to subfertility and infertility in Australian general practice: a focus on Aboriginal and Torres Strait Islander females.

OBJECTIVE: To investigate the management of subfertility and infertility among Aboriginal and Torres Strait Islander females attending Australian general practice. METHODS: Cross-sectional study of 1,258,581 women (18-49 years) attending general practice between January 2011 and June 2019, utilising data from NPS MedicineWise MedicineInsight, a national general practice database in Australia. RESULTS: The prevalence of subfertility/infertility encounters was lower for Aboriginal and Torres Strait Islander females (12.37 per 1,000) than for non-Indigenous females (16.62 per 1,000). Aboriginal and Torres Strait Islander females with a subfertility/infertility encounter were younger and more likely to live outside Major cities and in areas of socioeconomic disadvantage than non-Indigenous females. Rates of prescribed infertility medications were not different between groups, however Aboriginal and Torres Strait Islander females were more likely to receive a pelvic ultrasound (24.30% vs. 19.90%); tests for luteinizing hormone (31.89% vs. 25.65%); testosterone (14.93% vs. 9.96%) and; glycated haemoglobin (HbA1c) (6.32% vs. 3.41%),but less likely to receive an anti-müllerian hormone test (2.78% vs. 7.04%). CONCLUSIONS: Lower encounter rates for infertility/subfertility among Aboriginal and Torres Strait Islander peoples may indicate access issues, preferred use of Aboriginal community-controlled health centres or younger average age at first birth and thus less age-related infertility. IMPLICATIONS FOR PUBLIC HEALTH: Future efforts should focus on maximising the inclusiveness of infertility surveillance. There is also a need for further research into the experiences of and preferences for infertility care and associated barriers among Aboriginal and Torres Strait Islander people.

Menopause care delivery in the time of COVID-19: evaluating the acceptability of telehealth services for women with early and usual age menopause.

OBJECTIVES: This study aimed to explore women's and clinician's experiences and acceptability of telehealth use within a specialized multidisciplinary menopause service during the COVID-19 pandemic. METHODS: In-depth qualitative semi-structured interviews were analyzed via thematic inductive approaches. Telehealth acceptability was guided by the Nonadoption, Abandonment, and Challenges to the Scale-Up, Spread, and Sustainability of Health and Care Technologies (NASSS) framework. RESULTS: A heterogeneous group of 18 women who had attended the menopause service and six clinicians (gynecologists and endocrinologists) were interviewed. The majority of women and clinicians perceived telehealth as an acceptable way to deliver menopause care. Benefits of telehealth delivery were identified; themes centered around convenience, greater access to care and improved safety. Telehealth challenges included perceived impacts on personalized quality of care, patient-related logistical issues and system/organizational-related issues. A hybrid flexible delivery model combining telehealth and face-to-face care was recommended, following the easing of COVID-19 restrictions. Improvements to support embedding and adaptation of telehealth into routine care were described. CONCLUSION: In this study, telehealth was viewed as acceptable, supporting the ongoing delivery of a hybrid service model of telehealth and face-to-face menopause care. The findings provide valuable information to improve the menopause service to meet the needs of women during the ongoing current pandemic and beyond.

Exploring the acceptability and experience of receiving diabetes and pregnancy care via telehealth during the COVID-19 pandemic: a qualitative study.

BACKGROUND: The COVID-19 pandemic has significantly impacted the delivery of diabetes in pregnancy care and general maternity care. This study aimed to explore the experiences and acceptability of telehealth use in diabetes in pregnancy care during the COVID-19 pandemic, from the perspectives of pregnant women and their clinicians. The secondary aim was to explore the experiences of pregnant women receiving general maternity care via telehealth during the COVID-19 pandemic. METHODS: In-depth qualitative semi-structured interviews were undertaken and analysed via thematic inductive approaches. The Nonadoption, Abandonment, and Challenges to the Scale-Up, Spread, and Sustainability of Health and Care Technologies Framework (NASSS) was applied. RESULTS: Eigthteen interviews were conducted with culturally and linguistically diverse pregnant women and 4 clinicians (endocrinologists and dietitians). All interviewees were satisfied with telehealth as a positive alternative to face-to-face consultations for diabetes care during the COVID-19 pandemic. Numerous benefits of delivering diabetes care via telehealth were discussed and themes centred around greater access to care, economic benefits and improved safety. Most barriers concerned the adopters (clinicians), yet, feasible and realistic suggestions to overcome barriers were voiced. The scope for technology adaptation and ongoing embedment into routine diabetes care was described. Overall, a hybrid flexible delivery model, predominantly consisting of telephone consultations, with some face-to-face consultations for initial diabetes appointments was recommended for future care. The use of telehealth in replacement of face-to-face appointments for general maternity care was perceived as reducing care quality. CONCLUSION: In this study, telehealth was viewed as acceptable to women and clinicians for diabetes in pregnancy care, supporting the ongoing delivery of a hybrid service model of telehealth and face-to-face care. These findings provide valuable information to improve diabetes in pregnancy services to meet the needs of women during the COVID-19 pandemic and beyond.

'No sugar', 'no junk food', 'do more exercise' - moving beyond simple messages to improve the health of Aboriginal women with Hyperglycaemia in Pregnancy in the Northern Territory - A phenomenological study.

BACKGROUND: Globally, rates of hyperglycaemia in pregnancy are highest among Indigenous women. The highest prevalence has been documented among Aboriginal women in the Northern Territory of Australia. Despite knowledge of this for over two decades, there has been very limited examination of the specific needs and experiences of Aboriginal women regarding this condition. QUESTION: How do Aboriginal women with hyperglycaemia in pregnancy understand and experience this condition, and how can their care be improved? METHODS: A phenomenological methodology underpinned semi-structured in-depth interviews with 35 Aboriginal women and seven health professionals across the Northern Territory. Data were inductively analysed. FINDINGS: The findings revealed that in general, participants in this study could recite simple health messaging regarding diabetes (e.g. 'no sugar'), but many lacked in-depth knowledge and this affected the management of their condition. Nevertheless, many identified pregnancy as a powerful motivator for change, signalling scope to improve health messaging. Women consistently expressed the need for diabetes education that was culturally appropriate, a clear desire for maternity care that was family-centred, based on respectful relationships with the same care provider, and respected Aboriginal ways of knowing and being. CONCLUSION: Existing health messaging around hyperglycaemia in pregnancy has limited reach with Aboriginal women in the Northern Territory. Reducing the burden of hyperglycaemia in pregnancy among these women requires a sustained commitment to redesign of maternity and diabetes care to incorporate the cultural and social context of women's lives.

Women's perspectives of early menopause: development of a word cloud.

Objective: Early menopause (EM), menopause aged <45 years, occurs spontaneously or secondary to medical treatments and is associated with multiple health impacts. A word cloud is an image where the word size reflects the frequency of use. We aimed to assess the perspectives of women with EM using a word cloud.Methods: Women diagnosed with EM, recruited from clinics/community, completed a survey including the open-ended question 'What words do you associate with EM?'. Demographics and medical history were collected. Data analysis included descriptive statistics, identification of word themes/stems/synonyms, word frequency, and chi-square test. A word cloud was constructed from words used by two or more women using 'Wordle' (www.wordle.net).Results: Responses were obtained from 190/263 participants. The mean age was 54 ± 11 years, with EM diagnosed at age 38 ± 5 years. The cause of EM was unknown (30% of women), bilateral oophorectomy (27%), cancer therapy (25%), or autoimmune/genetic/metabolic (17%). The commonest words reported were hot flushes (36.8% of women), mood swings (20.5%), and infertility (16.8%), which varied with age and cause of EM. Few women reported neutral/positive words.Conclusion: Most words that women associate with EM have negative connotations and refer to symptoms. A word cloud is a novel way to illustrate women's perspectives.

Diabetes care in remote Australia: the antenatal, postpartum and inter-pregnancy period.

BACKGROUND: Aboriginal and Torres Strait Islander women experience high rates of diabetes in pregnancy (DIP), contributing to health risks for mother and infant, and the intergenerational cycle of diabetes. By enhancing diabetes management during pregnancy, postpartum and the interval between pregnancies, the DIP Partnership aims to improve health outcomes and reduce risks early in the life-course. We describe a mixed methods formative study of health professional's perspectives of antenatal and post-partum diabetes screening and management, including enablers and barriers to care. METHODS: Health professionals involved in providing diabetes care in pregnancy, from a range of health services across the Northern Territory, completed the survey (n = 82) and/or took part in interviews and/or focus groups (n = 62). RESULTS: Qualitative findings highlighted factors influencing the delivery of care as reported by health professionals, including: whose responsibility it is, access to care, the baby is the focus and pre-conception care. The main challenges were related to: disjointed systems and confusion around whose role it is to provide follow-up care beyond six weeks post-partum. Quantitative findings indicated that the majority of health professionals reported confidence in their own skills to manage women in the antenatal period (62%, 40/79) and slightly lower rates of confidence in the postpartum interval (57%, 33/58). CONCLUSION: These findings regarding whose role it is to provide postpartum care, along with opportunities to improve communication pathways and follow up care have informed the design of a complex health intervention to improve health systems and the provision of DIP related care.

Birth outcomes in women with gestational diabetes managed by lifestyle modification alone: The PANDORA study.

AIMS: To assess outcomes of women in the Pregnancy and Neonatal Diabetes Outcomes in Remote Australia (PANDORA) cohort with gestational diabetes mellitus (GDM) managed by lifestyle modification compared with women without hyperglycaemia in pregnancy. METHODS: Indigenous (n = 97) and Europid (n = 113) women managed by lifestyle modification were compared to women without hyperglycaemia (n = 235). Multivariate linear and logistic regressions assessed whether GDM-lifestyle women had poorer outcomes compared to women without hyperglycaemia. RESULTS: Women with GDM-lifestyle had higher body mass index and lower gestational weight gain than women without hyperglycaemia. On univariate analysis, gestational age at delivery was lower and induction rates were higher in women with GDM-lifestyle than without hyperglycaemia. On multivariable regression, GDM-lifestyle was associated with lower gestational age at delivery (by 0.73 weeks), lower birthweight z-score (by 0.26, p = 0.007), lower likelihood of large for gestational age (LGA) [OR (95% CI): 0.55 (0.28, 1.02), p = 0.059], and greater likelihood of labour induction [2.34 (1.49, 3.66), p < 0.001] than women without hyperglycaemia. CONCLUSION: Women with GDM managed by lifestyle modification had higher induction rates and their offspring had lower birthweight z-scores, with a trend to lower LGA than those without hyperglycaemia in pregnancy. Further studies are indicated to explore reasons for higher induction rates.

Impact of different glycaemic treatment targets on pregnancy outcomes in gestational diabetes.

AIM: With no current randomized trials, we explored the impact of tight compared with standard treatment targets on pregnancy outcomes in gestational diabetes mellitus (GDM). METHODS: This cohort study of singleton births ≥ 28 weeks' gestation was conducted at two major Australian maternity services (2009-2013). Standardized maternal, neonatal and birth outcomes were examined using routine healthcare data and compared for women with GDM at Service One (n = 2885) and Service Two (n = 1887). Services applied different treatment targets: Service One (standard targets, reference group) fasting < 5.5 mmol/l, 2-h postprandial < 7.0 mmol/l; Service Two (tight targets) fasting < 5.0 mmol/l, 2-h postprandial < 6.7 mmol/l. Multivariable regression with propensity score adjustment was used to examine associations between targets and outcomes. RESULTS: GDM prevalence and insulin use were 7.9% and 31% at Service One, and 5.7% and 46% at Service Two. There were no differences in primary outcomes: birthweight > 90th centile [adjusted odds ratio (OR) 1.06, 95% confidence interval (CI) 0.87-1.30] and < 10th centile (OR 0.84, 95% CI 0.70-1.01), or secondary outcomes gestational hypertension, pre-eclampsia, shoulder dystocia or a perinatal composite. Service Two with tight targets had increased induction of labour (OR 3.63, 95% CI 3.17-4.16), elective Caesarean section (OR 1.75, 95% CI 1.37-2.23) and Apgar scores < 7 at 5 min (OR 1.54, 95% CI 1.05-2.25), decreased hypoglycaemia (OR 0.76, 95% CI 0.61-0.94]), jaundice (OR 0.47, 95% CI 0.35-0.63) and respiratory distress (OR 0.68, 95% CI 0.47-0.98). CONCLUSIONS: Tight GDM treatment targets were associated with greater insulin use and no difference in primary birthweight outcomes. The service with tight targets had higher obstetric intervention, lower rates of reported hypoglycaemia, jaundice, respiratory distress and lower Apgar scores. High-quality interventional data are required before tight treatment targets can be implemented.

Health service changes to address diabetes in pregnancy in a complex setting: perspectives of health professionals.

BACKGROUND: Australian Aboriginal and Torres Strait Islander women have high rates of gestational and pre-existing type 2 diabetes in pregnancy. The Northern Territory (NT) Diabetes in Pregnancy Partnership was established to enhance systems and services to improve health outcomes. It has three arms: a clinical register, developing models of care and a longitudinal birth cohort. This study used a process evaluation to report on health professional's perceptions of models of care and related quality improvement activities since the implementation of the Partnership. METHODS: Changes to models of care were documented according to goals and aims of the Partnership and reviewed annually by the Partnership Steering group. A 'systems assessment tool' was used to guide six focus groups (49 healthcare professionals). Transcripts were coded and analysed according to pre-identified themes of orientation and guidelines, education, communication, logistics and access, and information technology. RESULTS: Key improvements since implementation of the Partnership include: health professional relationships, communication and education; and integration of quality improvement activities. Focus groups with 49 health professionals provided in depth information about how these activities have impacted their practice and models of care for diabetes in pregnancy. Co-ordination of care was reported to have improved, however it was also identified as an opportunity for further development. Recommendations included a central care coordinator, better integration of information technology systems and ongoing comprehensive quality improvement processes. CONCLUSIONS: The Partnership has facilitated quality improvement through supporting the development of improved systems that enhance models of care. Persisting challenges exist for delivering care to a high risk population however improvements in formal processes and structures, as demonstrated in this work thus far, play an important role in work towards improving health outcomes.

Preconception care for women with type 2 diabetes mellitus: A mixed-methods study of provider knowledge and practice.

AIMS: Preconception care may decrease adverse pregnancy outcomes associated with pre-existing diabetes mellitus. Aboriginal Australians are at high risk of type 2 diabetes mellitus (T2DM), with earlier onset. We explored practitioner views on preconception care delivery for women with T2DM in the Northern Territory, where 31% of births are to Aboriginal women. METHODS: Mixed-methods study including cross-sectional survey of 156 health practitioners and 11 semi-structured interviews. RESULTS: Practitioners reported low attendance for preconception care however, 51% provided counselling on an opportunistic basis. Rural/remote practitioners were most likely to find counselling feasible. The majority (69%) utilised appropriate guidelines and addressed lifestyle modifications including smoking (81%), weight management (79%), and change medications appropriately such as ceasing ACE inhibitors (69%). Fewer (40%) prescribed the recommended dose of folate (5mg) or felt comfortable recommending delaying pregnancy to achieve optimal preconception glucose control (42%). Themes identified as barriers to care included the complexity of care setting and infrequent preconception consultations. There was a focus on motivation of women to make informed choices about conception, including birth spacing, timing and contraception. Preconception care enablers included cross-cultural communication, a multi-disciplinary care team and strong client-based relationships. CONCLUSIONS: Health practitioners are keen to provide preconception counselling and reported knowledge of evidence-based guidelines. Improvements are needed in recommending high dose folate and optimising glucose control. Cross-cultural communication and team-based care were reported as fundamental to successful preconception care in women with T2DM. Continued education and policy changes are required to support practitioners in opportunities to enhance pregnancy planning.

Polycystic ovary syndrome and metabolic syndrome in Indigenous Australian women.

BACKGROUND: Polycystic ovary syndrome (PCOS) affects around 15% of Indigenous women who are also a group at high risk of cardiometabolic disease. AIM: To explore the impact of PCOS on metabolic syndrome in Indigenous women. METHODS: A cross-sectional reproductive health questionnaire, biochemical and anthropometric assessments, of 109 Indigenous women (35 with PCOS and 74 without PCOS) aged 15-44 years in and around Darwin between 2003 and 2005. PCOS was defined using the National Institutes of Health criteria, and metabolic syndrome (MetS) using the National Cholesterol Education Programme Adult Treatment Programme III criteria. The outcome was prevalence of MetS by PCOS status; relationship of PCOS with MetS before and after adjustment for markers of obesity and insulin resistance. RESULTS: Women with PCOS had a significantly higher body mass index (BMI) (P = 0.0001) and MetS was more frequent in women with PCOS (51%) than those without PCOS (23%) (P = 0.003). The most frequent components of MetS in both groups were a high density lipoprotein cholesterol ≤1.29 mmol/L (80% PCOS, 55% non-PCOS) and a waist circumference >88 cm (77% PCOS, 41% non-PCOS); these were significantly more frequent in women with PCOS (P = 0.01). In logistic regression models, PCOS was significantly associated with MetS by itself but not after adjustment for BMI or sex hormone binding globulin. CONCLUSIONS: While MetS was more common in Indigenous women with PCOS, PCOS was not an independent predictor of MetS. This may be because obesity and insulin resistance are integral parts of PCOS and are the mechanisms through which PCOS exerts metabolic effects.

Contraception use and pregnancy outcomes in women with polycystic ovary syndrome: data from the Australian Longitudinal Study on Women's Health.

STUDY QUESTION: Do contraception use, pregnancy outcome and number of children differ in women with and without polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Women with PCOS were less likely to report use of contraception and more likely to report a miscarriage, whilst number of children was similar between groups. WHAT IS KNOWN ALREADY: The oral contraceptive pill is used in the management of PCOS, but the patterns of contraception use in women with PCOS is not known. In women with PCOS who undergo assisted reproduction, the risk of pregnancy loss appears higher, yet pregnancy loss and family size among community-based women with PCOS is not known. STUDY DESIGN, SIZE AND DURATION: This is a cross-sectional analysis of a longitudinal cohort study. Mailed survey data were collected at five time points (years 1996, 2000, 2003, 2006 and 2009). Data from respondents to Survey 4 (2006), aged 28-33 (n = 9145, 62% of the original cohort aged 18-23 years) were analysed. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study was conducted in a general community setting. Data from participants who responded to the questions on PCOS, contraception and pregnancy outcome were analysed. The main outcome measures were self-reported PCOS, body mass index (BMI), contraception use, pregnancy loss and number of children. MAIN RESULTS AND THE ROLE OF CHANCE: In women aged 28-33 years, women with PCOS were less likely to be using contraception (61 versus 79%, P < 0.001) and more likely to be trying to conceive (56 versus 45%, P < 0.001), compared with women not reporting PCOS. A greater proportion of women with PCOS reported pregnancy loss (20 versus 15%, P = 0.003). PCOS was not independently associated with pregnancy loss; however, BMI was independently associated with pregnancy loss in the overweight and obese groups (OR 1.2, 95% CI 1.04-1.4, P = 0.02 and OR 1.4, 95% CI 1.1-1.6, P = 0.001, respectively). Fertility treatment use was also independently associated with pregnancy loss (adjusted OR 3.2, 95% CI 2.4-4.2, P < 0.001). There was no significant difference in number of children between women with and without PCOS. LIMITATIONS, REASON FOR CAUTION: PCOS, contraception use and pregnancy outcome data were self-reported. Attrition occurred, but is reasonable compared with similar longitudinal cohort studies. WIDER IMPLICATIONS OF THE FINDINGS: This community-based cohort aged 28-33 years provides insights into the contraceptive use, pregnancy loss and family size of a large cohort of unselected women. Women reporting PCOS had lower rates of contraception use and were more likely to be currently trying to conceive, suggesting that they may be aware of potential fertility challenges, yet in those not planning to conceive, contraceptive use was low and further education may be required. Despite prior reports of higher rates of pregnancy loss in PCOS, usually from infertility services, in this community-based population, PCOS was not independently associated with pregnancy loss, yet independent risk factors for pregnancy loss included higher BMI, were higher in PCOS. The number of children per woman was similar in the both groups, albeit with more infertility treatment in PCOS. This may reassure women with PCOS that with access to fertility treatment, family sizes appear similar to women not reporting PCOS.

Touching and feeling: differences in pleasant touch processing between glabrous and hairy skin in humans.

Previous functional magnetic resonance imaging studies in two rare patients, together with microneurography and psychophysical observations in healthy subjects, have demonstrated a system of mechanosensitive C-fiber tactile (CT) afferents sensitive to slowly moving stimuli. They project to the posterior insular cortex and signal pleasant aspects of touch. Importantly, CTs have not been found in the glabrous skin of the hand, yet it is commonly observed that glabrous skin touch is also perceived as pleasant. Here we asked if the brain processing of pleasant touch differs between hairy and glabrous skin by stroking the forearm and glabrous skin of the hand during positron emission tomography. The data showed that, when contrasting slow brush stroking on the forearm with slow brush stroking on the palm, there were significant activations of the posterior insular cortex and mid-anterior orbitofrontal cortex. The opposite contrast showed a significant activation of the somatosensory cortices. Although concurrent psychophysical ratings showed no differences in intensity or pleasantness ratings, a subsequent touch questionnaire in which subjects used a newly developed 'touch perception task' showed significant difference for the two body sites. Emotional descriptors received higher ratings on the forearm and sensory descriptors were rated more highly on the palm. The present findings are consistent with the hypothesis that pleasant touch from hairy skin, mediated by CT afferents, is processed in the limbic-related cortex and represents an innate non-learned process. In contrast, pleasant touch from glabrous skin, mediated by A-beta afferents, is processed in the somatosensory cortex and represents an analytical process dependent on previous tactile experiences.

Cross-modal integration of intranasal stimuli: a functional magnetic resonance imaging study.

Most odorants, in addition to the olfactory system, also activate the intranasal trigeminal system. Recent studies have shown that pure trigeminal stimulation activates somatosensory regions as well as regions traditionally thought of as primary olfactory areas. As a main aim of this study we wished to a) ascertain which brain regions are responsive to an "artificially" bimodal odor composed of a trigeminal (CO(2)) and an olfactory stimulant (phenyl ethyl alcohol, PEA) and b) determine if presenting CO(2) and PEA simultaneously activates different brain regions than when presenting them individually. Fifteen men were scanned using functional magnetic resonance imaging while smelling PEA, CO(2), and a mixture of both stimuli (CO(2)PEA) presented simultaneously. Odors were presented monorhinally to the right nostril in a block design. The contrast between CO(2)PEA and baseline revealed areas implicated in the processing of both olfactory and trigeminal stimuli. When the mixture was contrasted with the sum of its single components (CO(2)PEA-{CO(2)+PEA}), activations in integration centers (left superior temporal and right intraparietal sulcus) and in orbitofrontal areas (left medial and lateral orbitofrontal cortex) were detected. The opposite contrast ({CO(2)+PEA}-CO(2)PEA) did not reveal any significant activation. In contrast to studies which have used natural mixed olfactory/trigeminal stimuli, we have shown that the perception of an artificial mixed olfactory/trigeminal stimulus activates, as opposed to inhibiting the olfactory cortex. Further, we also conclude that a mixed olfactory/trigeminal stimulus appears to lead to higher cortical activations than the sum of its parts.

Functional neuroimaging of odor imagery.

We used positron emission tomography (PET) to investigate brain regions associated with odor imagery. Changes in regional cerebral blood flow (CBF) during odor imagery were compared with changes during nonspecific expectation of olfactory stimuli and with those during odor perception. Sixty-seven healthy volunteers were screened for their odor imagery (with a paradigm developed in a previous study), and 12 of them, assessed to be "good odor imagers," participated in the neuroimaging part of the study. Imagination of odors was associated with increased activation in several olfactory regions in the brain: the left primary olfactory cortical (POC) region including piriform cortex, the left secondary olfactory cortex or posterior orbitofrontal cortex (OFC), and the rostral insula bilaterally. Furthermore, blood flow in two regions within the right orbitofrontal cortex correlated significantly with the behavioral measure of odor imagery during scanning. Overall, the findings indicated that neural networks engaged during odor perception and imagery overlap partially.

Sperm incorporation in Xenopus laevis: characterisation of morphological events and the role of microfilaments.

Scanning and transmission electron microscopy were used to determine the morphological changes in the egg plasma membrane associated with sperm binding, fusion and incorporation in Xenopus laevis. Sperm incorporation in Xenopus is rapid, occurring within 3-5 min following addition of sperm. Images have been obtained of both early sperm-egg interactions and fertilisation bodies. Additionally, two drugs that specifically alter F-actin dynamics, latrunculin and jasplakinolide, were used to determine whether sperm incorporation is a microfilament-dependent process. Jasplakinolide did not prevent sperm incorporation, cortical granule exocytosis or cortical contraction, suggesting these events can occur without depolymerisation of existing, stabilised filaments. Latrunculin A, which competes with thymosin beta4 in ooplasm for binding actin monomer, did not inhibit cortical granule exocytosis, but blocked cortical contraction in 100% of eggs at a concentration of 5 microM. Although a single penetrating sperm was found on an egg pretreated in latrunculin, fertilisation bodies were never observed. At < 5 microM latrunculin, many eggs did undergo cortical contraction with some exhibiting severe distortions of the plasma membrane and abnormal accumulations of pigment granules. Preincubation of eggs in jasplakinolide before latrunculin mitigated both these effects to some degree. However, eggs incubated in latrunculin either prior to or after insemination never progressed through first cleavage.

Neurodegenerative stimuli induce persistent ADF/cofilin-actin rods that disrupt distal neurite function.

Inclusions containing actin-depolymerizing factor (ADF) and cofilin, abundant proteins in adult human brain, are prominent in hippocampal and cortical neurites of the post-mortem brains of Alzheimer's patients, especially in neurites contacting amyloid deposits. The origin and role of these inclusions in neurodegeneration are, however, unknown. Here we show that mediators of neurodegeneration induce the rapid formation of transient or persistent rod-like inclusions containing ADF/cofilin and actin in axons and dendrites of cultured hippocampal neurons. Rods form spontaneously within neurons overexpressing active ADF/cofilin, suggesting that the activation (by dephosphorylation) of ADF/cofilin that occurs in response to neurodegenerative stimuli is sufficient to induce rod formation. Persistent rods that span the diameter of the neurite disrupt microtubules and cause degeneration of the distal neurite without killing the neuron. These findings suggest a common pathway that can lead to loss of synapses.