Plasticity of the gastrocnemius elastic system in response to decreased work and power demand during growth.

Elastic energy storage and release can enhance performance that would otherwise be limited by the force-velocity constraints of muscle. Although functional influence of a biological spring depends on tuning between components of an elastic system (the muscle, spring-driven mass and lever system), we do not know whether elastic systems systematically adapt to functional demand. To test whether altering work and power generation during maturation alters the morphology of an elastic system, we prevented growing guinea fowl (Numida meleagris) from jumping. We compared the jump performance of our treatment group at maturity with that of controls and measured the morphology of the gastrocnemius elastic system. We found that restricted birds jumped with lower jump power and work, yet there were no significant between-group differences in the components of the elastic system. Further, subject-specific models revealed no difference in energy storage capacity between groups, though energy storage was most sensitive to variations in muscle properties (most significantly operating length and least dependent on tendon stiffness). We conclude that the gastrocnemius elastic system in the guinea fowl displays little to no plastic response to decreased demand during growth and hypothesize that neural plasticity may explain performance variation.

The integration of sensory feedback in the modulation of anuran landing preparation.

Controlled landing requires preparation. Mammals and bipedal birds vary how they prepare for landing by predicting the timing and magnitude of impact from the integration of visual and non-visual information. Here, we explore how the cane toad Rhinella marina - an animal that moves primarily through hopping - integrates sensory information to modulate landing preparation. Earlier work suggests that toads may modulate landing preparation using predictions of impact timing and/or magnitude based on non-visual sensory feedback during takeoff rather than visual cues about the landing itself. We disentangled takeoff and landing conditions by hopping toads off platforms of different heights while measuring electromyographic (EMG) activity of an elbow extensor (m. anconeus) and capturing high-speed images to quantify whole body and forelimb kinematics. This enabled us to test how toads integrate visual and non-visual information in landing preparation. We asked two questions: (1) when they conflict, do toads correlate landing preparation with takeoff or landing conditions? And (2) for hops with the same takeoff conditions, does visual information alter the timing of landing preparation? We found that takeoff conditions are a better predictor of the onset of landing preparation than landing conditions, but that visual information is not ignored. When hopping off higher platforms, toads start to prepare for landing later when takeoff conditions are invariant. This suggests that, unlike mammals, toads prioritize non-visual sensory feedback about takeoff conditions to coordinate landing, but that they do integrate visual information to fine-tune landing preparation.

The delivery of heavy menstrual bleeding services in England and Wales after publication of national guidelines: a survey of hospitals.

BACKGROUND: In 2007-2008, two UK-based organisations, the National Institute for Health and Clinical Excellence and the Royal College of Obstetricians and Gynaecologists, published guidelines for the management of care and organisation of outpatient services for women with heavy menstrual bleeding (HMB). In 2010, this study was conducted to provide an update on guideline-related services provided in England and Wales, and whether they are consistent with national clinical guidelines two to three years after publication. METHODS: An organisational survey of outpatient gynaecology clinics was conducted of 221 hospitals in 154 acute National Health Service (NHS) trusts in England and Wales. A questionnaire was distributed to all hospitals to examine provision of diagnostic and therapeutic services in outpatient settings. Descriptive statistics were used to summarize results. RESULTS: The response rate was 100%. For diagnosis, 80% of hospitals had ultrasound, 87% had hysteroscopy, and 98% had endometrial biopsy available. Overall, 76% of hospitals provided an information leaflet, 8% referred patients to a website for information, and 20% did not provide any written information. A dedicated menstrual bleeding clinic was present in 38% of hospitals. Only 30% of hospitals reported that they have a local written protocol regarding the care and management of women with HMB. CONCLUSION: The majority of hospitals offer appropriate diagnostic and surgical services for women with HMB. However, local protocol development may not reflect the local services. It may be that hospitals are finding it difficult to summon resources to provide clinics for women with menstrual disorders.

African American Adolescent Mothers' Childbirth Support From Fathers, Grandmothers, Nurses, Doctors, and Doulas.

The morning after giving birth in a large urban hospital, 121 African American adolescents participating in a community doula program identified the people who had been with them during labor and birth and narrated their birth stories. Besides medical providers, the people most likely to be present for the birth were the infants' fathers (n = 73, 60%), the mothers' mothers (n = 70, 58%), and their doulas (n = 100, 83%). Birth stories were coded to identify types of support provided by different people. Mothers' mothers, infants' fathers, and doulas were more likely to be mentioned in the stories as providers of emotional and instrumental support than were medical providers. Doulas were more likely to be mentioned as providers of information than were family members or medical providers.

Making meaning of motherhood: Self and life transitions among African American adolescent mothers.

Although adolescent childbearing is widely viewed as a major social problem, and research suggests that young mothers and their children are at risk for poor economic and academic outcomes, these ideas may be in need of revision. Recent scholarship has pointed out that young mothers have been unfairly blamed and stigmatized for problems that should be attributed to social and economic inequality, racism, and poverty. The present study extends that research by listening to the voices of young mothers. In total, 179 urban African American women were asked at 4, 12, and 24 months after giving birth to describe how their lives had changed since becoming a mother. A team of coders content coded themes with rigorous checks for intercoder reliability. Positive themes were far more prevalent than negative themes. Motherhood was often described as a positive developmental change, providing the young women with a sense of maturity, responsibility, motivation, and commitment to placing the baby's needs ahead of their own. Motherhood was sometimes described as a life-turning point whereby young women turned away from undesirable activities and became focused on school, work, and their family's future. Challenges reflected common stresses of parenting for people of all ages, such as lack of sleep and burden of caregiving, but also limited time to socialize with friends. Findings suggest that although policymakers and professionals view adolescent parenthood as a social ill to be eradicated, for the mothers themselves, the experience is more complex, meaningful, and positive. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Using big data in pediatric oncology: Current applications and future directions.

Pediatric cancer is a rare disease with a low annual incidence, which presents a significant challenge in being able to collect enough data to fuel clinical discoveries. Big data registry trials hold promise to advance the study of pediatric cancers by allowing for the combination of traditional randomized controlled trials with the power of larger cohort sizes. The emergence of big data resources and data-sharing initiatives are becoming transformative for pediatric cancer diagnosis and treatment. This review discusses the uses of big data in pediatric cancer, existing pediatric cancer registry initiatives and research, the challenges in harmonizing these data to improve accessibility for study, and building pediatric data commons and other important future endeavors.

Altering the Mechanical Load Environment During Growth Does Not Affect Adult Achilles Tendon Properties in an Avian Bipedal Model.

Tendon mechanical properties respond to altered load in adults, but how load history during growth affects adult tendon properties remains unclear. To address this question, we adopted an avian model in which we altered the mechanical load environment across the growth span. Animals were divided at 2 weeks of age into three groups: (1) an exercise control group given the opportunity to perform high-acceleration movements (EXE, n = 8); (2) a sedentary group restricted from high-intensity exercise (RES, n = 8); and (3) a sedentary group also restricted from high-intensity exercise and in which the gastrocnemius muscles were partially paralyzed using repeated bouts of botulinum toxin-A injections (RES-BTX, n = 8). Video analysis of bird movement confirmed the restrictions eliminated high-intensity exercise and did not alter time spent walking and sitting between groups. At skeletal maturity (33-35 weeks) animals were sacrificed for analysis, consisting of high-field MRI and material load testing, of both the entire free Achilles tendon and the tendon at the bone-tendon junction. Free tendon stiffness, modulus, and hysteresis were unaffected by variation in load environment. Further, the bone-tendon junction cross-sectional area, stress, and strain were also unaffected by variations in load environment. These results suggest that: (a) a baseline level of low-intensity activity (standing and walking) may be sufficient to maintain tendon growth; and (b) if this lower threshold of tendon load is met, non-mechanical mediated tendon growth may override the load-induced mechanotransduction signal attributed to tendon remodeling in adults of the same species. These results are important for understanding of musculoskeletal function and tendon health in growing individuals.

Parent relationship quality and infant-mother attachment.

This project examined interrelations between father-mother conflict, father support of mother, maternal behavior, and infant-mother attachment within a sample of 79 African American families living in a highly stressed urban community. Father support of mother was not related to maternal parenting behavior or infant attachment. Conflicted mother-father relationships were associated with problematic maternal behavior, low maternal sensitivity, infant attachment insecurity, and infant attachment disorganization. The associations between parental conflict and both infant attachment disorganization and insecurity were buffered in families in which fathers co-resided with the mother. Consistent with theory and prior research, links were also observed between maternal sensitive-responsiveness and infant attachment security and between problematic maternal parenting and infant attachment disorganization. However, maternal parenting behavior did not mediate the relation between parental conflict and infant attachment. Results are discussed with respect to whether and under what circumstances child exposure to parent conflict can have a direct effect on infant-mother attachment that is not mediated through dyadic infant-mother interaction.

Use of Wearable, Mobile, and Sensor Technology in Cancer Clinical Trials.

As the availability and sophistication of mobile health (mHealth) technology (wearables, mobile technology, and sensors) continues to increase, there is great promise that these tools will be transformative for clinical trials and drug development. This review provides an overview of the current landscape of potential measurement options, including the various types of data collected, methods/tools for collecting them, and a crosswalk of available options. The opportunities and potential drawbacks of mHealth in cancer clinical trials are discussed. Specific concerns related to data accuracy, provenance, and regulatory issues are highlighted, with suggestions for how to address these in future research. Next steps for establishing mHealth methods and tools as legitimate and accepted measures in oncology clinical trials include continuation of regulatory definition by the FDA; establishment of security standards and protocols; refinement and implementation of methods to establish and document data accuracy; and finally, creation of feedback loops wherein regulators receive updates from researchers with better and more timely data, which should decrease trial times and lessen drug development costs. Implementing mHealth technologies into cancer clinical trials has the potential to transform and propel oncology drug development and precision medicine to keep pace with the rapidly increasing developments in genomics and immunology.

The principles of cascading power limits in small, fast biological and engineered systems.

Mechanical power limitations emerge from the physical trade-off between force and velocity. Many biological systems incorporate power-enhancing mechanisms enabling extraordinary accelerations at small sizes. We establish how power enhancement emerges through the dynamic coupling of motors, springs, and latches and reveal how each displays its own force-velocity behavior. We mathematically demonstrate a tunable performance space for spring-actuated movement that is applicable to biological and synthetic systems. Incorporating nonideal spring behavior and parameterizing latch dynamics allows the identification of critical transitions in mass and trade-offs in spring scaling, both of which offer explanations for long-observed scaling patterns in biological systems. This analysis defines the cascading challenges of power enhancement, explores their emergent effects in biological and engineered systems, and charts a pathway for higher-level analysis and synthesis of power-amplified systems.

Reliability of a preventability model in maternal death and morbidity.

OBJECTIVE: The purpose of this study was to measure the reliability of a model that defines preventability in maternal morbidity and death. STUDY DESIGN: One hundred cases of serious morbidity and death among peripartum women were reviewed by 2 independent groups of medical experts to identify potentially preventable provider or system events that may have led to the progression of illness. RESULTS: Seventy-seven percent of the cases had concordant findings in both groups regarding the identification of any preventable events. Interrater agreement, which was measured by Cohen's Kappa, was 0.49, which suggests moderate to good reliability. Cases with multiple comorbidities, poor documentation, or preventable patient factors tended to have higher levels of disagreement. CONCLUSION: There was high agreement between the 2 groups regarding the identification of preventable events that impact maternal morbidity and death. The reliability of this model for the assessment of preventability is an important step for improvement in obstetric and medical care.

Mothers' representations of their infants and parenting behavior: Associations with personal and social-contextual variables in a high-risk sample.

Associations between mothers' psychological distress, experiences of verbal and violent relational conflict, representations of the relationships with their infants, and parenting behavior were examined in 100 African American mothers of 17- to 20-month-old infants. Maternal representations of infants were assessed via the Working Model of the Child Interview (WMCI; Zeanah, Benoit, Hirshberg, & Barton, 1986). Results showed that mothers who experienced more conflict with their own mothers had increased odds of having disengaged representations of the relationship with their infants. Mothers who experienced more conflict with their infants' fathers had increased odds of having distorted views of their infants. Mothers who reported more hostile psychological symptomalogy had greater odds of not having a balanced representation of their infants (distorted or disengaged). Additionally, mothers with disengaged representations were less sensitive, more passive, and used less encouragement and guidance with their children. Maternal hostility and conflict were directly related to parenting and were not mediated by representations. Results show that representations and parenting behavior are linked and multiply determined.

Data Commons to Support Pediatric Cancer Research.

The falling costs and increasing fidelity of high-throughput biomedical research data have led to a renaissance in cancer surveillance and treatment. Yet, the amount, velocity, and complexity of these data have overcome the capacity of the increasing number of researchers collecting and analyzing this information. By centralizing the data, processing power, and tools, there is a valuable opportunity to share resources and thus increase the efficiency, power, and impact of research. Herein, we describe current data commons and how they operate in the oncology landscape, including an overview of the International Neuroblastoma Risk Group data commons as a paradigm case. We outline the practical steps and considerations in building data commons. Finally, we discuss the unique opportunities and benefits of creating a data commons within the context of pediatric cancer research, highlighting the particular advantages for clinical oncology and suggested next steps.

Disparities in mortality among high risk pregnant women in Illinois: a population based study.

PURPOSE: Researchers are increasingly studying maternal mortality in the context of maternal morbidity in order to identify risk and protective factors operating at each point along the morbidity-mortality continuum. This study examined factors associated with mortality in pregnant women with severe morbidity. In particular, the Black-White disparity was examined. METHODS: Illinois vital records data were linked to identify maternal deaths and other pregnant women with severe morbidity. Pregnancy-related deaths and high risk survivors were compared and case fatality rates were computed. Condition-specific and multivariable analyses were conducted, and time of death was examined. RESULTS: The overall risk of maternal death was 37.1 per 10,000 high risk pregnant women in Illinois from 1994 to 1998. Women who were older, African American, unmarried, or living in Chicago were at elevated risk of death. The adjusted relative risk for the Black-White disparity was 3.7 among all high risk pregnant women and 8.5 among women with hypertensive disorders. A greater proportion of African American and Hispanic women died within 7 days of delivery compared to White women. CONCLUSIONS: Medical risk status alone cannot explain disparities in maternal mortality. The Black-White disparity for risk of death persisted in both overall and condition-specific analyses.

Morbidity and mortality in pregnancy: laying the groundwork for safe motherhood.

The Safe Motherhood Initiative is a global effort to reduce deaths and illnesses among women and infants. Despite the relatively low maternal mortality rate in the United States, ensuring safe motherhood is still critical. For several reasons, it is important to study maternal mortality and morbidity. First, the pregnancy-related mortality ratio has not declined; second, evidence suggests that at least half of pregnancy-related deaths may be preventable through changes in patient, provider, or system factors; and third, mortality rates are disproportionately high among certain racial and ethnic groups. In addition, deaths are only the tip of the iceberg: maternal morbidity also represents a huge burden of disease for women and their families. Broadening the research focus and prevention efforts to include the study of maternal morbidity, especially near-miss morbidity-life-threatening morbidity-can strengthen the study of maternal death. This paper presents an overview of maternal mortality and morbidity including incidence and etiology, issues and challenges for measurement, and issues of preventability. We also address specific strategies for change for health care providers, federal and state health agencies, and the public health community.

Defining a conceptual framework for near-miss maternal morbidity.

Maternal mortality is the major indicator used to monitor maternal health in the United States. For every woman who dies, however, many suffer serious life-threatening complications of pregnancy. Yet relatively little attention has been given to identifying a general category of morbidities that could be called near misses. Characterizing near-miss morbidity is valuable for monitoring the quality of hospital-based obstetric care and for assessing the incidence of life-threatening complications. Cases of near-miss morbidity also provide an appropriate comparison group both for dinical case review and for epidemiologic analysis. This paper presents an initial framework and a process for the definition and identification of near-miss morbidity that minimizes loss of information yet has practical utility. A clinical review team classified 22 of 186 women as near misses and 164 as other severe morbidity. A quantitative score classified 28 women as near misses and 156 as other severe morbidity. Precise classification of near-miss morbidity is the first step in analyzing factors that may differentiate survival from death on the continuum from morbidity to mortality. Ultimately, a methodology for the identification and analysis of near-miss morbidity will allow for integrated morbidity and mortality reviews that can then be institutionalized. The results will serve as important models for other researchers, state health agencies, and regionalized perinatal systems that are engaged in morbidity and mortality surveillance.

International Classification of Diseases-9th revision coding for preeclampsia: how accurate is it?

OBJECTIVE: The purpose of this study was to evaluate the accuracy of the International Classification of Diseases-9th revision codes for preeclampsia and eclampsia. STUDY DESIGN: The University of Illinois Medical Center at Chicago discharge database was used to identify 135 women from 1999 through 2001 whose disease was coded as having preeclampsia or eclampsia. With American College of Obstetrics and Gynecology criteria as the gold standard, the diagnosis that was determined through chart review was compared with the International Classification of Diseases-9th revision code that was present in the discharge database. Patients were classified as true cases if the International Classification of Diseases-9th revision code matched the American College of Obstetricians and Gynecologists diagnosis; the positive predictive value of the code was then calculated. RESULTS: The overall positive predictive value for the complete sample was only 54%, but the positive predictive value for severe preeclampsia was 84.8%, which was high compared with mild preeclampsia (45.3%) and eclampsia (41.7%). Diagnostic (clinician) error was the most common reason for miscoding error. CONCLUSION: The findings suggest that International Classification of Diseases-9th revision codes for preeclampsia/eclampsia vary greatly in their accuracy of diagnosis. Therefore, a review of medical records is required when data are being gathered on the incidence of preeclampsia and eclampsia.

The continuum of maternal morbidity and mortality: factors associated with severity.

OBJECTIVE: The goal of this study was to examine whether sociodemographic, clinical, and other service-related factors, as well as preventability issues affect a woman's progression along the continuum of morbidity and mortality. STUDY DESIGN: This was a case-control study of pregnancy-related deaths, women with near-miss morbidity, and those with other severe, but not life threatening, morbidity. Factors associated with maternal outcome were examined. RESULTS: Provider factors (related to preventability) and clinical diagnosis were significantly associated with progression along the continuum after controlling for sociodemographic characteristics (P < .01 for both associations). CONCLUSION: In order to improve mortality rates, we must understand maternal morbidity and how it may lead to death. This study shows that important initiatives include addressing preventability, in particular, provider factors, which may play a role in moving women along the continuum of morbidity and mortality.