Exploring pathways to successful aging among older black lesbians and sexual minority women: A focus on life satisfaction and intersectional factors

PURPOSE

Satisfaction with life is a core aspect of successful aging, which is influenced by a broad range of factors, including health, socioeconomic status, and social relationships. Black lesbians experience various social challenges, including racism, sexism, ageism, and heterosexualism, that may present as deterrents to aging successfully. To develop better policies and programs in support of successful aging among all adults, an understanding of the unique components associated with their intersecting identities must be explored. This study was carried out to gain a better understanding of how Black lesbians and other Black sexual minority women (BSMW) view successful aging within the context of life satisfaction.

METHODS

Inferential statistics were used to determine relationships between satisfaction with life (SWLS-3) and selected independent variables. Backward stepwise regression was conducted to ascertain significant relationships of the study outcome variable.

RESULTS

The respondents were 118 Black lesbians and other BSMW aged 50 and above. Independent t-tests showed that those living with a partner had a significantly higher SWLS-3. Backwards stepwise regression indicated the predictor variables for higher rates of SWLS-3 to be harmony in life, annual household income, and provider sensitivity/cultural competence to their patient being Black.

CONCLUSION

This study provides insight on factors increasing and diminishing satisfaction with life for aging Black lesbians and other BSMW. Future research should replicate this study with a more diverse and nationally representative sample, especially given the study limitations of having recruited a highly educated sample during a global pandemic.

Caregiving Among Older Black Same-Gender-Loving Women During the COVID-19 Pandemic: Findings From Qualitative Research

BACKGROUND AND OBJECTIVES

Few data on caregiving during the coronavirus disease 2019 pandemic use an intersectional lens to attend to how multiple social categories, such as gender, age, race, and sexual orientation, shape caregiving experiences. This analysis sought to explore caregiving experiences of aging Black same-gender-loving women.

RESEARCH DESIGN AND METHODS

Sixteen focus groups were conducted with 4-8 participants each (N = 102) from across the United States. Audio-recorded discussions lasted for approximately 90 min and were transcribed verbatim. Two analysts coded transcripts for discussions related to caregiving and used content analysis to identify themes.

RESULTS

Participants engaged in caregiving for children, parents, family, friends, and neighbors. They provided physical, economical, instrumental, and/or secondary caregiving; and sometimes received care themselves. The pandemic heavily affected their stress level and mental health as well as their intimate partner relationships. Discussions mostly offered descriptions of increased caregiving difficulty caused by the pandemic. However, a few participants identified ways the pandemic made caregiving easier; changed caregiving without making it easier or harder; or thwarted their ability to provide care.

DISCUSSION AND IMPLICATIONS

Older Black same-gender-loving women described some pandemic caregiving experiences that diverged from the existing literature, demonstrating the importance of considering how gender, race, age, and sexual orientation affect caregiving experiences during a pandemic fraught with health inequities. Ensuring the multiply marginalized caregivers have access to the practical and emotional support they need is critical for advancing health equity and preparing for future pandemics.

Caregiving During the COVID-19 Pandemic: A Cross-Sectional Study with Older Cisgender Sexual Minority Women in the United States

Purpose: This study describes prevalence of caregiving before and after the onset of the COVID-19 pandemic among racially diverse older cisgender sexual minority women, examines factors associated with caregiving, and assesses relationships between caregiving and health. Methods: A convenience sample of participants aged ≥50 years completed self-administered online surveys assessing sociodemographic characteristics, caregiver status, self-rated health, and depressive symptoms. Bivariate statistics compared response variables by race, caregiver status, and timing of caregiving relative to the pandemic. Results: Of 365 participants, 82.7% identified as lesbian or gay and 41.1% as Black/African American; 40% were caregivers before (n = 32), during (n = 34), or both before and during (n = 80) the pandemic. A greater proportion of caregivers lived with a partner (45.9% vs. 35.6%, p = 0.06), were unemployed (37.7% vs. 29.7%, p = 0.07), and had high school or lower education (11.6% vs. 5%, p = 0.09). No differences were found in self-rated health by caregiver status; however, a higher proportion of Black (vs. White) caregivers reported good to excellent physical health (77.9% vs. 62.9%, p = 0.05). Caregivers more frequently reported depressive symptoms (28.1% vs. 17.8%, p = 0.03). Caregivers both before and during the pandemic had lower educational attainment than those who provided care only before or only during the pandemic (p = 0.04). Conclusion: Caregiving was common among older sexual minority women during the pandemic and experiences varied by race and other social factors. Consideration of these intersecting experiences is important for fully understanding caregiver experiences during COVID-19. Overall, caregiving was associated with depressive symptoms, underscoring the importance of psychosocial support for all caregivers.

Engaging Black sexual minority women in breast cancer research: Lessons in community partnerships

BACKGROUND

Black sexual minority women (BSMW) face significant breast cancer health inequities and are underrepresented in health research because of historical and present-day exclusion. However, there exists no peer-reviewed literature on best practices for the inclusion of BSMW in cancer research. "Our Breast Health: The Access Project" was a national primary data collection study in June 2018 through October 2019 that aimed to identify facilitators and barriers to breast cancer care among BSMW, and that successfully recruited the highest number of BSMW for any national breast cancer screening study at the time of its publication.

METHODS

The present analysis highlights best practices for reaching BSMW by examining by how effective various recruitment sources were at recruiting BSMW. Recruitment partners were grouped into several categories: (1) cancer focused, (2) Black women or sexual minority women focused, (3) BSMW focused, (4) social media, and (5) other. Then logistic regression was used to estimate the odds that a particular recruitment source category could recruit BSMW compared with other categories.

RESULTS

Partnerships with community-based organizations led by and intended for BSMW were the most successful at recruiting BSMW, demonstrating the importance of an intersectional approach to recruitment. Community-based organizations focused on BSMW specifically were 26 times more successful in recruiting BSMW to the study compared with recruiting Black women who were not sexual minorities (odds ratio, 26.43 [95% CI, 7.50-93.10]).

CONCLUSIONS

Successful recruitment enables breast cancer research grounded in the perspectives of BSMW, which can generate key findings that have the potential to remedy longstanding health inequities for this population.

OLDER BLACK LESBIANS' NEEDS AND EXPECTATIONS IN RELATION TO LONG-TERM CARE FACILITY USE

The older adult sexual minority (SM) population encompasses a vast array of individuals from diverse backgrounds. However, there is a dearth of gerontological research that focuses on the experiences of SM subgroups, particularly older Black lesbians. The purpose of this study was to explore older Black lesbians’ needs and expectations in relation to the utilization of long-term care (LTC) facilities. We conducted secondary data analysis using data from 14 focus groups (n=100) that discussed health and aging with older Black lesbians. Transcriptions were analyzed in NVivo 12 using content analysis and structural coding. Three major themes were identified in relation to needs and expectations for LTC facility use: (1) consideration of or plans established to utilize a LTC facility, (2) concern for care facility environment, and (3) a desire to build one’s own community instead of LTC use. Within these themes, prominent topics included having to rely on LTC due to a lack of family or social support, the possibility of being isolated and stifling their lesbian identity and creating communities of mutual support to avoid facility-based care. These findings illustrate how older Black lesbians are planning for a potential need for LTC, their concerns about utilizing LTC, and alternative approaches to avoid LTC use. There remains a continued need for LTC communities that are inclusive and supportive of SM older adults as well as more SM-only communities where older adults can live openly and authentically.

Older Black Lesbians' Needs and Expectations in Relation to Long-Term Care Facility Use

There is a dearth of long-term care research that focuses on the expectations and experiences of older sexual minority (SM) adults. That research dwindles further when examining subgroups within that population such as older Black lesbians. The purpose of this study was to explore older Black lesbians' needs and expectations in relation to the utilization of long-term care (LTC) facilities. We conducted secondary data analysis using data from 14 focus groups that discussed health and aging with older Black lesbians. Transcriptions were analyzed in NVivo using deductive content analysis and structural coding. Three themes were identified in relation to needs and expectations for LTC facility use: (1) consideration or established plans to utilize a LTC facility, (2) concern for care facility environment, and (3) a desire to build one's own community. These findings illustrate how older Black lesbians are planning for a potential need for LTC, their concerns about utilizing LTC, and alternative approaches to avoid LTC use. There remains a continued need for LTC communities that are inclusive and supportive of SM older adults as well as more SM-only communities where older adults can live openly and authentically.

Delays in breast cancer care by race and sexual orientation: Results from a national survey with diverse women in the United States

BACKGROUND

Despite known differences in breast cancer by both race and sexual orientation, data on the intersectional experiences of Black sexual minority women (BSMW) along the care continuum are scant. This study sought to understand delays in breast cancer care by examining the intersection of race and sexual orientation.

METHODS

This online, cross-sectional survey enrolled racially and sexually diverse women aged ≥ 35 years who had been diagnosed with breast cancer within the prior 10 years or had an abnormal screening in the prior 24 months. The authors calculated summary statistics by race/sexual orientation categories, and they conducted univariate and multivariable modeling by using multiple imputation for missing data.

RESULTS

BSMW (n = 101) had the highest prevalence of care delays with 5.17-fold increased odds of a care delay in comparison with White heterosexual women (n = 298) in multivariable models. BSMW reported higher intersectional stigma and lower social support than all other groups. In models adjusted for race, sexual orientation, and income, intersectional stigma was associated with a 2.43-fold increase in care delays, and social support was associated with a 32% decrease in the odds of a care delay.

CONCLUSIONS

Intersectional stigma may be an important driver of breast cancer inequities for BSMW. Reducing stigma and ensuring access to appropriate social support that addresses known barriers can be an important approach to reducing inequities in the breast cancer care continuum.

Beyond Black and White: race and sexual identity as contributors to healthcare system distrust after breast cancer screening among US women

OBJECTIVE

Healthcare system distrust (HCSD) has been linked to poor breast cancer outcomes. Previous HSCD analyses have focused on Black-White disparities; however, focusing only on race ignores the complex set of factors that form identity. We quantified the contributions of race and sexual minority (SM) identity to HCSD among US women who had received breast cancer screening.

METHODS

This cross-sectional study used intersectionality decomposition methods to assess the degree to which racial and SM identity contributed to disparate responses to the validated 9-item HCSD Scale. The sample included online survey participants identifying as a Black or White woman living in the US, with a self-reported abnormal breast cancer screening result in the past 24 months and/or breast cancer diagnosis since 2011.

RESULTS

Of 649 participants, 49.4% of Black SM women (n = 85) were in the highest HCSD tertile, followed by 37.4% of White SM women (n = 123), 24.4% of Black heterosexual women (n = 156), and 19% of White heterosexual women. Controlling for age, 72% of the disparity in HCSD between Black SM women and White heterosexual women was due to SM status, 23% was due to racial identity, and 3% was due to both racial and SM identity.

CONCLUSIONS

SM identity emerged as the largest driver of HCSD disparities; however, the combined racial and SM disparity persisted. Excluding sexual identity in HCSD studies may miss an important contributor. Interventions designed to increase the HCS's trustworthiness at the provider and system levels should address both racism and homophobia.

"This is some mess right here": Exploring interactions between Black sexual minority women and health care providers for breast cancer screening and care

BACKGROUND

Few studies have explored how the intersection of race and sexual identity contribute to breast cancer disparities for Black sexual minority women (SMW). Issues within patient-provider relationships, including bias, contribute to health disparities for minority groups. The authors used constructs from self-determination theory (SDT) to explore the nature of health care provider interactions in breast cancer screening and care among Black SMW.

METHODS

Participants were sampled nationally through social media, targeted emails, and referrals. Qualitative, in-depth interviews were conducted with 15 Black cisgender SMW, ages 38 to 64 years, who had a breast cancer diagnosis or recent abnormal mammogram. Interviews were conducted face-to-face or online, audio-recorded, and transcribed verbatim. Two analysts coded the interviews. Codes were analyzed across interviews to identify themes salient to SDT.

RESULTS

Themes aligned with the SDT constructs of relatedness and autonomy. Some participants discussed feeling most understood by Black and/or female providers who shared at least 1 of their identities. Feeling understood through shared identity contributed to participants feeling seen and heard by their providers. Participants who discussed negative experiences with providers believed that the provider made negative assumptions about them based on their race and/or sexual orientation.

CONCLUSIONS

When interacting with health care providers for breast cancer screening and care, Black SMW face specific challenges related to their multiply marginalized social position. Reducing health care provider bias toward Black SMW may improve patients' desires to continue in care. Providing equitable care while acknowledging and respecting women with multiply marginalized identities may improve the nature of these interactions.

Associations of social cohesion and quality of life with objective and perceived built environments: a latent profile analysis among seniors

BACKGROUND

Healthy aging requires support from local built and social environments. Using latent profile analysis, this study captured the multidimensionality of the built environment and examined relations between objective and perceived built environment profiles, neighborhood social cohesion and quality of life among seniors.

METHODS

In total, 693 participants aged 66-97 were sampled from two US locales in 2005-2008 as part of the Senior Neighborhood Quality of Life Study (SNQLS). Perceived social cohesion and quality of life were assessed using validated surveys. Six objective (geographic information system (GIS)-based) and seven perceived built environment latent profiles generated in previous SNQLS publications were used for analyses. Mixed-effects models estimated social cohesion and quality of life separately as a function of the built environment profiles.

RESULTS

More walkable and destination-rich perceived built environment profiles were associated with higher social cohesion and quality of life. Objective built environment profiles were not associated with social cohesion and only positively associated with quality of life in only one locale (Baltimore/DC).

CONCLUSIONS

Latent profile analysis offered a comprehensive approach to assessing the built environment. Seniors who perceived their neighborhoods to be highly walkable and recreationally dense experienced higher neighborhood social cohesion and quality of life, which may set the stage for healthier aging.

Breast Cancer Screening and Care Among Black Sexual Minority Women: A Scoping Review of the Literature from 1990 to 2017

Introduction: Black women are more likely to be diagnosed at later stages of breast cancer compared with White women due to lower frequency of screening and lack of timely follow-up after abnormal screening results. Disparities in breast cancer screening, risk, and mortality are present within both Black women and sexual minority communities; however, there exists limited research concerning breast cancer care among Black sexual minority women. Materials and Methods: This scoping review examines the literature from 1990 to 2017 of the breast cancer care continuum among Black sexual minority women, including behavioral risk factors, screening, treatment, and survivorship. A total of 91 articles were identified through PubMed, PsycINFO, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases. Fifteen articles were selected for data extraction, which met the criteria for including Black/African American women, discussing breast cancer care among both racial and sexual minorities, and being a peer-reviewed article. Results: The 15 articles were primarily within urban contexts, and defined sexual minorities as lesbian or bisexual women. Across all the studies, Black sexual minority women were highly under-represented, and key conclusions are not fully applicable to Black sexual minority women. Sexual minority women had a higher prevalence of breast cancer risk factors (i.e., nulliparity, fewer mammograms, higher alcohol intake, and lower oral contraceptive use). Furthermore, some studies noted homophobia from health providers as potential barriers to engagement in care for sexual minority women. Conclusions: The lack of studies concerning Black sexual minority women in breast cancer care indicates the invisibility of a group that experiences multiple marginalized identities. More research is needed to capture the dynamics of the breast cancer care continuum for Black sexual minority women.

P1541The relation between right ventricular-pulmonary circulation coupling and aging in healthy population

Purpose

The aim of the study was to evaluate the right ventricular (RV) structure and functional adaptation to age, in particular the RV pulmonary circulation (PC) coupling and physiologic correlates.

Methods

1177 healthy subjects aged 16–100 years were enrolled. They underwent general medical evaluation and a comprehensive TTE included RV systolic such as tricuspid annular plane systolic excursion (TAPSE), pulmonary artery systolic pressure (PASP) derived from the tricuspid regurgitation (TR), the derived RV-pulmonary circulation (PC) coupling or TAPSE/PASP, pulmonary vascular resistances (PVR) derived from TR/RV outflow tract velocity (RVOT VTI) and diastolic function parameters. The cohort was divided in 4 groups of age: group 1: 300 subjects from 18 to 35 years; group 2: 383 subjects from 36 to 50; group 3: 451 from 50 to 79 years and group 4: 43 subjects > than 80 years of age The oldest subjects were completely independent in daily living activities. The groups were compared by ANOVA and the difference was adjusted by gender, BMI and mean arterial pressure. For each group the difference between genders was tested by T-Test. Multivariate analysis was used to evaluate the relationship between RV function and structure indexes and covariates selected according to pathologic relevance.

Results

There was a progressive increase in blood pressure (BP) according to age. The RV longitudinal diameter, right E/A ratio, right ventricular outflow tract acceleration time and TAPSE/PASP decreased according to age increase (p<0.0001). The right atrial volume indexed by BSA, PASP, PVR increase with age (p<0.0001). Either TAPSE or Sm were unaffected by age. Women had constantly smaller RV longitudinal diameters, right atrium volume index, TAPSE and TAPSE/PASP (p<0.001). In the multiple regression analysis, though the proportion of variance of the dependent variables predicted by the independent ones was very small, age, BSA, gender, E/Em and the longitudinal diameter of the RV were independent predictors of TAPSE/PASP. Heart rate, left ventricular (LV) diastolic function, stroke volume (SV) and TR were independently related to Sm, while age, BSA, LV diastolic function and SV were independently related to TAPSE.

Conclusion

With ageing there is a progressive involvement not only of the LV in terms of adaptation to increase afterload related to arterial stiffness but also of the RV. With age PVR and PASP increase while RV contractility is still unchanged. While the RV adapts very well to volume overload, even the physiologic increase in PASP with age, causes a RV-PC coupling impairment.

Biomechanics of the human intervertebral disc: A review of testing techniques and results

Many experimental testing techniques have been adopted in order to provide an understanding of the biomechanics of the human intervertebral disc (IVD). The aim of this review article is to amalgamate results from these studies to provide readers with an overview of the studies conducted and their contribution to our current understanding of the biomechanics and function of the IVD. The overview is presented in a way that should prove useful to experimentalists and computational modellers. Mechanical properties of whole IVDs can be assessed conveniently by testing 'motion segments' comprising two vertebrae and the intervening IVD and ligaments. Neural arches should be removed if load-sharing between them and the disc is of no interest, and specimens containing more than two vertebrae are required to study 'adjacent level' effects. Mechanisms of injury (including endplate fracture and disc herniation) have been studied by applying complex loading at physiologically-relevant loading rates, whereas mechanical evaluations of surgical prostheses require slower application of standardised loading protocols. Results can be strongly influenced by the testing environment, preconditioning, loading rate, specimen age and degeneration, and spinal level. Component tissues of the disc (anulus fibrosus, nucleus pulposus, and cartilage endplates) have been studied to determine their material properties, but only the anulus has been thoroughly evaluated. Animal discs can be used as a model of human discs where uniform non-degenerate specimens are required, although differences in scale, age, and anatomy can lead to problems in interpretation.

The Effect of Posture on the Strength of the Lumbar Spine

Experiments were performed on cadaveric lumbar intervertebral joints in order to assess the effects of heavy lifting on the lumbar spine. It was found that in the simulated erect lordotic posture, the apophyseal joints can resist a significant proportion of the intervertebral compressive force. Slightly flexed lumbar joints have a compressive strength that comfortably exceeds the forces generated by heavy lifting. Hyperflexion just beyond the normal limit of motion can render lumbar intervertebral discs vulnerable to posterior prolapse when compressed by physiological loads. It is concluded that no injury should be sustained by the osteoligamentous lumbar spine as a result of a single heavy lift provided that the lumbar spine is kept slightly flexed.

Brain Structural and Vascular Anatomy Is Altered in Offspring of Pre-Eclamptic Pregnancies: A Pilot Study

BACKGROUND AND PURPOSE

Pre-eclampsia is a serious clinical gestational disorder occurring in 3%-5% of all human pregnancies and characterized by endothelial dysfunction and vascular complications. Offspring born of pre-eclamptic pregnancies are reported to exhibit deficits in cognitive function, higher incidence of depression, and increased susceptibility to stroke. However, no brain imaging reports exist on these offspring. We aimed to assess brain structural and vascular anatomy in 7- to 10-year-old offspring of pre-eclamptic pregnancies compared with matched controls.

MATERIALS AND METHODS

Offspring of pre-eclamptic pregnancies and matched controls (n = 10 per group) were recruited from an established longitudinal cohort examining the effects of pre-eclampsia. Children underwent MR imaging to identify brain structural and vascular anatomic differences. Maternal plasma samples collected at birth were assayed for angiogenic factors by enzyme-linked immunosorbent assay.

RESULTS

Offspring of pre-eclamptic pregnancies exhibited enlarged brain regional volumes of the cerebellum, temporal lobe, brain stem, and right and left amygdalae. These offspring displayed reduced cerebral vessel radii in the occipital and parietal lobes. Enzyme-linked immunosorbent assay analysis revealed underexpression of the placental growth factor among the maternal plasma samples from women who experienced pre-eclampsia.

CONCLUSIONS

This study is the first to report brain structural and vascular anatomic alterations in the population of offspring of pre-eclamptic pregnancies. Brain structural alterations shared similarities with those seen in autism. Vascular alterations may have preceded these structural alterations. This pilot study requires further validation with a larger population to provide stronger estimates of brain structural and vascular outcomes among the offspring of pre-eclamptic pregnancies.

Impact of placental growth factor deficiency on early mouse implant site angiogenesis

Effects of placental growth factor (PGF), an angiokine product of fetal trophoblasts and maternal decidual cells, on early decidual angiogenesis are undefined. We used whole-mount immunofluorescence analyses to compare uterus and gestation day 4.5-9.5 mouse implantation sites that differed genetically in fetal or maternal PGF deficiency. Implant site number and embryonic development were similar in Pgf(-/-) and Pgf(+/+) females although Pgf(-/-) lymphatic vessels were anomalous. Correct, fine branching angiogenesis of anti-mesometrial vessels required both conceptus and maternal PGF; correct mesometrial branching angiogenesis depended solely upon conceptus PGF. Thus, PGF is non-redundant for optimizing branching angiogenesis in early decidua.

Proton vibrational dynamics in lithium imide investigated through incoherent inelastic and Compton neutron scattering

In the present study we report neutron spectroscopic measurements on polycrystalline lithium imide, namely, incoherent inelastic neutron scattering at 20 K, and neutron Compton scattering from 10 K up to room temperature. From the former technique the H-projected density of phonon states up to 100 meV is derived, while the latter works out the spherically averaged single-particle (i.e., H, Li, and N) momentum distributions and, from this, the mean kinetic energies. Only for H at the lowest investigated temperature, non-gaussian components of its momentum distribution are detected. However, these components do not seem directly connected to the system anharmonicity, being fully compatible with the simple N-H bond anisotropy. Neutron data are also complemented by ab initio lattice dynamics simulations, both harmonic and, at room temperature, carried out in the framework of the so-called "quantum colored noise thermostat" method. The single-particle mean kinetic energies in lithium imide as a function of temperature show a quite peculiar behavior at the moment not reproduced by ab initio lattice dynamics methods, at least as far as H and Li are concerned. As matter of fact, neither their low temperature values nor their temperature trends can be precisely explained in terms of standard phonon calculations.

Attitudes and program preferences of African-American urban young adults about pre-exposure prophylaxis (PrEP)

We elicited attitudes about, and service access preferences for, daily oral antiretroviral pre-exposure prophylaxis (PrEP) from urban, African-American young men and women, ages 18-24 years, at risk for HIV transmission through their sexual and drug-related behaviors participating in eight mixed-gender and two MSM-only focus groups in Atlanta, Georgia. Participants reported substantial interest in PrEP associated with its perceived cost, effectiveness, and ease of accessing services and medication near to their homes or by public transportation. Frequent HIV testing was a perceived benefit. Participants differed about whether risk-reduction behaviors would change, and in which direction; and whether PrEP use would be associated with HIV stigma or would enhance the reputation for PrEP users. This provides the first information about the interests, concerns, and preferences of young adult African Americans that can be used to inform the introduction of PrEP services into HIV prevention efforts for this critical population group.

The role of Plantaris Longus in Achilles tendinopathy: a biomechanical study

BACKGROUND

The Plantaris Longus Tendon (PLT) may be implicated in Achilles (AT) tendinopathy. Different mechanical characteristics may be the cause. This study is designed to measure these.

METHODS

Six PLT and six AT were harvested from frozen cadavers (aged 65-88). Samples were stretched to failure using a Minimat 2000™ (Rheometric Scientific Inc.). Force and elongation were recorded. Calculated tangent stiffness, failure stress and strain were obtained. Averaged mechanical properties were compared using paired, one-tailed t-tests.

RESULTS

Mean stiffness was higher (p<0.001) in the PLT, measuring 5.71 N/mm (4.68-6.64), compared with 1.73 N/mm (1.40-2.22) in AT. Failure stress was also higher (p<0.01) in PLT: 1.42 N/mm(2) (0.86-2.23) AT: 0.20 N/mm(2) (0.16-0.25). Failure strain was less (p<0.05) in PLT: 14.1% (11.5-16.8) than AT: 21.8% (14.9-37.9).

CONCLUSIONS

The PLT is stiffer, stronger than AT, demonstrating potential for relative movement under load. The stiffer PLT could tether AT and initiate an inflammatory response.

Circulatory and renal consequences of pregnancy in diabetic NOD mice

OBJECTIVES

Women with diabetes have elevated gestational risks for severe hemodynamic complications, including preeclampsia in mid- to late pregnancy. This study employed continuous, chronic radiotelemetry to compare the hemodynamic patterns in non-obese diabetic (NOD) mice who were overtly diabetic or normoglycemic throughout gestation. We hypothesized that overtly diabetic, pregnant NOD mice would develop gestational hypertension and provide understanding of mechanisms in progression of this pathology.

STUDY DESIGN

Telemeter-implanted, age-matched NOD females with and without diabetes were assessed for six hemodynamic parameters (mean, systolic, diastolic, pulse pressures, heart rate and activity) prior to mating, over pregnancy and over a 72 h post-partum interval. Urinalysis, serum biochemistry and renal histopathology were also conducted.

RESULTS

Pregnant, normoglycemic NOD mice had a hemodynamic profile similar to other inbred strains, despite insulitis. This pattern was characterized by an interval of pre-implantation stability, post implantation decline in arterial pressure to mid gestation, and then a rebound to pre-pregnancy baseline during later gestation. Overtly diabetic NOD mice had a blood pressure profile that was normal until mid-gestation then become mildly hypotensive (-7 mmHg, P < 0.05), severely bradycardic (-80 bpm, P < 0.01) and showed signs of acute kidney injury. Pups born to diabetic dams were viable but growth restricted, despite their mothers' failing health, which did not rebound post-partum (-10% pre-pregnancy pressure and HR, P < 0.05).

CONCLUSIONS

Pregnancy accelerates circulatory and renal pathologies in overtly diabetic NOD mice and is characterized by depressed arterial pressure from mid-gestation and birth of growth-restricted offspring.

Isotope quantum effects on the water proton mean kinetic energy

A deep inelastic neutron scattering experiment, performed on D(2)O in the stable and metastable liquid phases, provides evidence for isotope quantum effects in the proton or deuteron single particle dynamics along the hydrogen bond. The deuteron mean kinetic energy extracted from the experimental data in the metastable supercooled phase (T = 276.15 K) exceeds the zero point energy and scales as sqrt[2] with that of protons in supercooled light water, at T = 269.15 K. The present data support the suggestion that even small changes in the short range environment of a deuteron or proton have a strong influence on its quantum behavior.

Attack on all fronts: functional relationships between aerial and root parasitic plants and their woody hosts and consequences for ecosystems

This review discusses how understanding of functional relationships between parasitic plants and their woody hosts have benefited from a range of approaches to their study. Gross comparisons of nutrient content between infected and uninfected hosts, or parts of hosts, have been widely used to infer basic differences or similarities between hosts and parasites. Coupling of nutrient information with additional evidence of key processes such as transpiration, respiration and photosynthesis has helped elucidate host-parasite relationships and, in some cases, the anatomical nature of their connection and even the physiology of plants in general. For example, detailed analysis of xylem sap from hosts and parasites has increased our understanding of the spatial and temporal movement of solutes within plants. Tracer experiments using natural abundance or enriched application of stable isotopes ((15)N, (13)C, (18)O) have helped us to understand the extent and form of heterotrophy, including the effect of the parasite on growth and functioning of the host (and its converse) as well as environmental effects on the parasite. Nutritional studies of woody hosts and parasites have provided clues to the distribution of parasitic plants and their roles in ecosystems. This review also provides assessment of several corollaries to the host-parasite association.