ABSTRACT
We consider the fluctuations in the number of particles in a box of sizeLdinZd,d⩾1, in the (infinite volume) translation invariant stationary states of the facilitated exclusion process, also called the conserved lattice gas model. When started in a Bernoulli (product) measure at densityρ, these systems approach, astâ∞, a 'frozen' state forρ⩽ρc, withρc=1/2ford = 1 andρc<1/2ford⩾2. Atρ=ρcthe limiting state is, as observed by Hexner and Levine, hyperuniform, that is, the variance of the number of particles in the box grows slower thanLd. We give a general description of how the variances at different scales ofLbehave asρâρc. On the largest scale,Lâ«L2, the fluctuations are normal (in fact the same as in the original product measure), while in a regionL1âªLâªL2, with bothL1andL2going to infinity asρâρc, the variance grows faster than normal. For1âªLâªL1the variance is the same as in the hyperuniform system. (All results discussed are rigorous ford = 1 and based on simulations ford⩾2.).
ABSTRACT
INTRODUCTION: Nephrotoxic medication (NTM) exposure is commonly associated with acute kidney injury (AKI) in the neonatal intensive care unit (NICU). Baby Nephrotoxic Injury Negated by Just-in-Time Action (NINJA) is a quality improvement program that assesses for AKI in those exposed to NTM with daily serum creatinine (SCr) levels. However, blood draws for SCr are invasive and have clinical disadvantages. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is a promising indicator of AKI. We tested the hypothesis that uNGAL could reliably screen for NTM-AKI in the Baby NINJA program. METHODS: This two-center prospective study screened 174 NICU subjects, of whom 148 met screening criteria from January 29, 2019, to September 18, 2020. Daily SCr and urine samples were obtained for up to 7 days of NTM exposure plus 2 days after exposure ended or end of AKI. AKI was defined by a SCr rise of 50% from baseline. The highest uNGAL obtained was evaluated to determine its relationship to the diagnosis of AKI. Logistic regression models were used to determine optimal uNGAL cutoffs. RESULTS: The negative predictive value of a uNGAL value ≥250 ng/mL was 96.8% (95% CI = 93.3-100%). Urine NGAL ≥400 ng/mL demonstrated the highest ROC-AUC value of 0.72 with a positive likelihood risk for AKI of 2.76 (1.39-4.13). DISCUSSION/CONCLUSION: We propose that uNGAL could be used to screen for NTM-AKI and thus replace many blood draws needed in those exposed to NTM. The ideal uNGAL threshold requires further investigation in infants.
Subject(s)
Acute Kidney Injury , Intensive Care Units, Neonatal , Infant , Infant, Newborn , Humans , Lipocalin-2/urine , Creatinine , Prospective Studies , Biomarkers , Acute Kidney Injury/chemically induced , Acute Kidney Injury/diagnosisABSTRACT
Pieter van Keep was a founder and the third president of the International Menopause Society (IMS). He died, sadly, in 1991. Since then, every retiring president of the IMS has delivered the Pieter van Keep Memorial Lecture. This is an edited version of that lecture delivered at the 18th World Congress of the IMS in Lisbon, Portugal in 2022. In the article, President Steven R. Goldstein describes the path he followed that led him to the presidency of the IMS, including his original entry into transvaginal ultrasound, then gynecologic ultrasound and, ultimately, menopausal ultrasound. His was the first description of the benign nature of simple ovarian cysts, the ability of transvaginal ultrasound to exclude significant tissue in patients with postmenopausal bleeding and the significance of endometrial fluid collections in postmenopausal patients, just to name a few. However, it was his description of the unusual ultrasound appearance in the uterus of women receiving tamoxifen therapy that allowed his entry into the world of menopause. This, ultimately, led to leadership positions, and ultimately the presidency of the American Institute of Ultrasound in Medicine, the North American Menopause Society and, finally, the IMS, all chronicled in this article. In addition, the article describes in detail the activities of the IMS during the COVID pandemic.
Subject(s)
COVID-19 , Humans , Female , Menopause , Endometrium/diagnostic imaging , Ultrasonography , PortugalABSTRACT
In a characterization of treatment rates and healthcare costs among patients with an osteoporotic-related fragility fracture overall and by site of care, costs were high and treatment rates were low. PURPOSE: Osteoporotic fractures can be debilitating, even fatal, among older adults. The cost of osteoporosis and related fractures is projected to increase to more than $25 billion by 2025. The objective of this analysis is to characterize disease-related treatment rates and healthcare costs of patients with an osteoporotic fragility fracture overall and by site of fracture diagnosis. METHODS: In this retrospective analysis, individuals with fragility fractures were identified in the Merative MarketScan® Commercial and Medicare Databases among women 50 years of age or older and diagnosed with fragility fracture between 1/1/2013 and 6/30/2018 (earliest fracture diagnosis = index). Cohorts were categorized by clinical site of care where the diagnosis of fragility fracture was made and were continuously followed for 12 months prior to and following index. Sites of care were inpatient admission, outpatient office, outpatient hospital, emergency room hospital, and urgent care. RESULTS: Of the 108,965 eligible patients with fragility fracture (mean age 68.8), most were diagnosed during an inpatient admission or outpatient office visit (42.7%, 31.9%). The mean annual healthcare costs among patients with fragility fracture were $44,311 (± $67,427) and were highest for those diagnosed in an inpatient setting ($71,561 ± $84,072). Compared with other sites of care at fracture diagnosis, patients diagnosed during an inpatient admission also had highest proportion of subsequent fractures (33.2%), osteoporosis diagnosis (27.7%), and osteoporosis therapy (17.2%) during follow-up. CONCLUSION: The site of care for diagnosis of fragility fracture affects treatment rates and healthcare costs. Further studies are needed to determine how attitude or knowledge about osteoporosis treatment or healthcare experiences differ at various clinical sites of care in the medical management of osteoporosis.
Subject(s)
Bone Density Conservation Agents , Osteoporosis , Osteoporotic Fractures , Humans , Female , Aged , United States , Retrospective Studies , Medicare , Osteoporosis/drug therapy , Health Care Costs , Data Analysis , Bone Density Conservation Agents/therapeutic useABSTRACT
In order to penetrate the egg, spermatozoa must undergo the acrosome reaction in close proximity to the egg. This process can take place only after a series of biochemical changes in the sperm, collectively termed capacitation, occur in the female reproductive tract. Sperm cells can undergo spontaneous-acrosome reaction(sAR) before reaching the vicinity of the egg, preventing successful fertilization. Several mechanisms were shown to protect sperm from undergoing sAR, and all of them are involved in proper capacitation. Here, we describe the involvement of protein acetylation in the mechanism that protects bovine spermatozoa from sAR. Incubation of bovine sperm under non-capacitation conditions revealed a strong increase in sAR that was significantly reduced in the presence of deacetylase inhibitors. Protein kinase A (PKA) is an essential key enzyme in sperm capacitation, and its inhibition results in high sAR. The reduction in sAR by hyperacetylation was independent of PKA activity. We previously demonstrated that calmodulin-kinase II (CaMKII) activity protects sperm from sAR, and here we show that its activity is essential for reduction in sAR by hyperacetylation. We further show that the 'exchange protein directly activated by Camp' (EPAC) mediates both protein lysine acetylation and the reduced rate of sAR caused by hyperacetylation. In conclusion, these results suggest a PKA-independent and EPAC-CaMKII dependent hyperacetylation mechanism that protects sperm from sAR.
Subject(s)
Acrosome Reaction , Calcium-Calmodulin-Dependent Protein Kinase Type 2 , Acetylation , Acrosome/metabolism , Acrosome Reaction/physiology , Animals , Cattle , Cyclic AMP-Dependent Protein Kinases/metabolism , Female , Guanine Nucleotide Exchange Factors/metabolism , Male , Semen/metabolism , Sperm Capacitation/physiology , Spermatozoa/metabolismABSTRACT
BACKGROUND: South Africa (SA) has embarked on a process to implement universal health coverage (UHC) funded by National Health Insurance (NHI). The 2019 NHI Bill proposes creation of a health technology assessment (HTA) body to inform decisions about which interventions NHI funds will cover under UHC. In practice, HTA often relies mainly on economic evaluations of cost-effectiveness and budget impact, with less attention to the systematic, specific consideration of important social, organisational and ethical impacts of the health technology in question. In this context, the South African Values and Ethics for Universal Health Coverage (SAVE-UHC) research project recognised an opportunity to help shape the health priority-setting process by providing a way to take account of multiple, ethically relevant considerations that reflect SA values. The SAVE-UHC Research Team developed and tested an SA-specific Ethics Framework for HTA assessment and analysis. OBJECTIVES: To develop and test an Ethics Framework for use in the SA context for health priority-setting. METHODS: The Framework was developed iteratively by the authors and a multidisciplinary panel (18 participants) over a period of 18 months, using the principles outlined in the 2015 NHI White Paper as a starting point. The provisional Ethics Framework was then tested with multi-stakeholder simulated appraisal committees (SACs) in three provinces. The membership of each SAC roughly reflected the composition of a potential SA HTA committee. The deliberations and dedicated focus group discussions after each SAC meeting were recorded, analysed and used to refine the Framework, which was presented to the Working Group for review, comment and final approval. RESULTS: This article describes the 12 domains of the Framework. The first four (Burden of the Health Condition, Expected Health Benefits and Harms, Cost-Effectiveness Analysis, and Budget Impact) are commonly used in HTA assessments, and a further eight cover the other ethical domains. These are Equity, Respect and Dignity, Impacts on Personal Financial Situation, Forming and Maintaining Important Personal Relationships, Ease of Suffering, Impact on Safety and Security, Solidarity and Social Cohesion, and Systems Factors and Constraints. In each domain are questions and prompts to enable use of the Framework by both analysts and assessors. Issues that arose, such as weighting of the domains and the availability of SA evidence, were discussed by the SACs. CONCLUSIONS: The Ethics Framework is intended for use in priority-setting within an HTA process. The Framework was well accepted by a diverse group of stakeholders. The final version will be a useful tool not only for HTA and other priority-setting processes in SA, but also for future efforts to create HTA methods in SA and elsewhere.
Subject(s)
Health Priorities , Universal Health Insurance , Biomedical Technology , Humans , South Africa , Technology Assessment, BiomedicalABSTRACT
The skin is an endocrine organ and a major target of hormones such as estrogens, androgens and cortisol. Besides vasomotor symptoms (VMS), skin and hair symptoms often receive less attention than other menopausal symptoms despite having a significant negative effect on quality of life. Skin and mucosal menopausal symptoms include dryness and pruritus, thinning and atrophy, wrinkles and sagging, poor wound healing and reduced vascularity, whereas skin premalignant and malignant lesions and skin aging signs are almost exclusively caused by environmental factors, especially solar radiation. Hair menopausal symptoms include reduced hair growth and density on the scalp (diffuse effluvium due to follicular rarefication and/or androgenetic alopecia of female pattern), altered hair quality and structure, and increased unwanted hair growth on facial areas. Hormone replacement therapy (HRT) is not indicated for skin and hair symptoms alone due to the risk-benefit balance, but wider potential benefits of HRT (beyond estrogen's effect on VMS, bone, breast, heart and blood vessels) to include skin, hair and mucosal benefits should be discussed with women so that they will be able to make the best possible informed decisions on how to prevent or manage their menopausal symptoms.
Subject(s)
Menopause , Quality of Life , Alopecia/etiology , Estrogen Replacement Therapy/adverse effects , Estrogens , Female , Hair , HumansSubject(s)
Cysts , Ovarian Neoplasms , Female , Humans , Ovarian Neoplasms/diagnostic imaging , Ovarian Neoplasms/pathology , UltrasonographyABSTRACT
Selective estrogen receptor modulators (SERMs) are synthetic molecules that bind to the estrogen receptor and can have agonistic activity in some tissues while being estrogen antagonistic in others. While not all SERMs are clinically available in all parts of the world, this article will review preclinical and clinical effects of various SERMs on bone. These include tamoxifen, used as adjuvant therapy in breast cancer patients as well as for breast cancer prevention; raloxifene, approved for osteoporosis prevention and treatment as well as breast cancer prevention; bazedoxifene, approved for prevention of osteoporosis and also in combination with conjugated equine estrogen for treatment of vasomotor symptoms and prevention of bone loss in postmenopausal patients; and ospemifene, approved for treatment of dyspareunia due to vulvovaginal atrophy/genitourinary syndrome of menopause. Thus, these SERMs are a diverse group of estrogen agonist/antagonists that seem to have class effects in the bone and breast, although the amount of clinical trial data is quite variable. However, there does not seem to be the same unidirectional class activity in tissues like the uterus or vagina. Health-care providers should be cognizant of all available information in helping patients make the best possible shared decision-making choices.
Subject(s)
Bone Density , Selective Estrogen Receptor Modulators , Bone Density/drug effects , Female , Humans , Selective Estrogen Receptor Modulators/pharmacology , Selective Estrogen Receptor Modulators/therapeutic useABSTRACT
BACKGROUND/OBJECTIVE: Older adults are at risk for tooth loss and compromised nutritional status. Our objective was to conduct a systematic review and meta-analysis to answer the following question: Among adults aged ≥60 y living in developed countries, what are the associations between tooth loss and nutritional status as assessed by a validated nutrition screening or assessment tool? METHODS: PRISMA guidelines were followed. PubMed, Scopus, CINAHL, Web of Science, and MEDLINE were searched for studies published in English between 2009 and 2019 that met inclusion criteria. Data extracted included study and participant characteristics, dentition, and nutritional status. Risk of bias was assessed with a modified Newcastle-Ottawa Scale. Random effects meta-analysis was used. RESULTS: Of the 588 unduplicated articles identified, 78 were reviewed in full text, and 7 met inclusion criteria. Six studies were combined for a meta-analysis, which revealed that individuals who were completely edentulous or who lacked functional dentition had a 21% increased likelihood of being at risk of malnutrition or being malnourished, as compared with those who were dentulous or had functionally adequate dentition (risk ratio, 1.21; 95% CI, 1.11 to 1.32; I2 = 70%). Whether the article statistically adjusted for medical history explained most of the heterogeneity in the pooled effect. CONCLUSIONS AND IMPLICATIONS: Findings suggest that older adults with tooth loss are at greater risk of malnutrition than those with functionally adequate dentition. Use of validated tools to assess risk of malnutrition in older adults with tooth loss is important to promote early intervention and referral to optimize nutrition and oral health status. Findings were limited by heterogeneity, risk of bias, and overall quality of the studies reviewed. Cohort studies that adjust for known confounders and use consistent approaches to assess tooth loss and nutritional status are needed. KNOWLEDGE TRANSFER STATEMENT: The results of this study suggest that older adults with tooth loss are at greater risk of malnutrition than those with functionally adequate dentition. Screening of this population for malnutrition by health care professionals, including dentists and dietitians, may result in corresponding referrals to optimize nutrition and oral health status. Further research is needed with consistent approaches to assess tooth loss and nutritional status.
Subject(s)
Malnutrition , Mouth, Edentulous , Tooth Loss , Aged , Eating , Humans , Malnutrition/diagnosis , Nutritional Status , Tooth Loss/epidemiologyABSTRACT
Growth extent and direction determine cell and whole-organ architecture. How they are spatio-temporally modulated to control size and shape is not well known. Here we tackled this question by studying the effect of brassinosteroid (BR) signalling on the structure of the root meristem. Quantification of the three-dimensional geometry of thousands of individual meristematic cells across different tissue types showed that the modulation of BR signalling yields distinct changes in growth rate and anisotropy, which affects the time that cells spend in the meristem and has a strong impact on the final root form. By contrast, the hormone effect on cell volume was minor, establishing cell volume as invariant to the effect of BR. Thus, BR has the highest effect on cell shape and growth anisotropy, regulating the overall longitudinal and radial growth of the meristem, while maintaining a coherent distribution of cell sizes. Moving from single-cell quantification to the whole organ, we developed a computational model of radial growth. The simulation demonstrates how differential BR-regulated growth between the inner and outer tissues shapes the meristem and thus explains the non-intuitive outcomes of tissue-specific perturbation of BR signalling. The combined experimental data and simulation suggest that the inner and outer tissues have distinct but coordinated roles in growth regulation.
Subject(s)
Brassinosteroids , Meristem , Plant Roots/cytology , Arabidopsis , Cell Shape , Cell Size , Meristem/cytology , Models, Biological , Signal TransductionABSTRACT
Osteoporosis and associated fractures present a major challenge in improving global health outcomes. Key clinical aspects are the definition of osteoporosis and associated fractures, fracture risk prediction, stratification of risk of fracture, intervention thresholds and the most appropriate intervention based on integration of aforementioned. Correct understanding and application of these concepts are essential to stem the increasing tide of fragility fractures associated with an aging population. The role of muscle strength and function, sarcopenia, and the newly emerging concept of osteosarcopenia in maintaining bone health are discussed in detail.
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Bone Density , Osteoporosis , Aged , Humans , MenopauseABSTRACT
The plate tectonic cycle produces chemically distinct mid-ocean ridge basalts and arc volcanics, with the latter enriched in elements such as Ba, Rb, Th, Sr and Pb and depleted in Nb owing to the water-rich flux from the subducted slab. Basalts from back-arc basins, with intermediate compositions, show that such a slab flux can be transported behind the volcanic front of the arc and incorporated into mantle flow. Hence it is puzzling why melts of subduction-modified mantle have rarely been recognized in mid-ocean ridge basalts. Here we report the first mid-ocean ridge basalt samples with distinct arc signatures, akin to back-arc basin basalts, from the Arctic Gakkel Ridge. A new high precision dataset for 576 Gakkel samples suggests a pervasive subduction influence in this region. This influence can also be identified in Atlantic and Indian mid-ocean ridge basalts but is nearly absent in Pacific mid-ocean ridge basalts. Such a hemispheric-scale upper mantle heterogeneity reflects subduction modification of the asthenospheric mantle which is incorporated into mantle flow, and whose geographical distribution is controlled dominantly by a "subduction shield" that has surrounded the Pacific Ocean for 180 Myr. Simple modeling suggests that a slab flux equivalent to ~13% of the output at arcs is incorporated into the convecting upper mantle.
ABSTRACT
Root meristem organization is maintained by an interplay between hormone signaling pathways that both interpret and determine their accumulation and distribution. The interacting hormones Brassinosteroids (BR) and auxin control the number of meristematic cells in the Arabidopsis root. BR was reported both to promote auxin signaling input and to repress auxin signaling output. Whether these contradicting molecular outcomes co-occur and what their significance in meristem function is remain unclear. Here, we established a dual effect of BR on auxin, with BR simultaneously promoting auxin biosynthesis and repressing auxin transcriptional output, which is essential for meristem maintenance. Blocking BR-induced auxin synthesis resulted in rapid BR-mediated meristem loss. Conversely, plants with reduced BR levels were resistant to a critical loss of auxin biosynthesis, maintaining their meristem morphology. In agreement, injured root meristems, which rely solely on local auxin synthesis, regenerated when both auxin and BR synthesis were inhibited. Use of BIN2 as a tool to selectively inhibit BR signaling yielded meristems with distinct phenotypes depending on the perturbed tissue: meristem reminiscent either of BR-deficient mutants or of high BR exposure. This enabled mapping of the BR-auxin interaction that maintains the meristem to the outer epidermis and lateral root cap tissues and demonstrated the essentiality of BR signaling in these tissues for meristem response to BR. BR activity in internal tissues however, proved necessary to control BR levels. Together, we demonstrate a basis for inter-tissue coordination and how a critical ratio between these hormones determines the meristematic state.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Brassinosteroids/metabolism , Gene Expression Regulation, Plant , Hormones/metabolism , Indoleacetic Acids/metabolism , Meristem/metabolism , Plant Roots/metabolismABSTRACT
OBJECTIVES: Numerous studies indicate that endometrial thickness of ≤ 4 mm on transvaginal ultrasound (TVS) is a reliable test to exclude endometrial cancer in women with postmenopausal bleeding (PMB), such that biopsy is not needed. However, not all postmenopausal women have anatomy that allows reliable measurement of endometrial thickness. This study was undertaken to evaluate the frequency of, and the reasons for, an inability to adequately visualize the endometrium on TVS. METHODS: A total of 472 consecutive asymptomatic postmenopausal women underwent TVS as part of their routine gynecological care. Their charts and TVS images were reviewed, and, if possible, endometrial thickness was recorded. If the endometrium was not adequately visualized, the reason for inadequacy was recorded, as judged by the examiner. Other demographic characteristics recorded included the number of years since menopause, body mass index (BMI) and current use of hormone replacement therapy. RESULTS: Of the 472 women, 292 (61.9%) had an endometrium that was well visualized, in whom endometrial thickness could be measured reliably (mean, 3.0 (range, 1.0-28.0) mm). In the other 180 postmenopausal women (38.1%), a distinct endometrium was not adequately visualized. The reasons for non-visualization were fibroids (n = 95, 20.1% of the overall cohort), adenomyosis (n = 35, 7.4% of the overall cohort) and an axial uterus (n = 50, 10.6% of the overall cohort). Mean interval from menopause was 14.0 (range, 1-50) years and 14.1 (range, 1-40) years in the visualized and non-visualized cohorts, respectively (P = 0.83). Mean BMI was 23.9 (range, 16.3-41.5) kg/m2 in the visualized cohort and 25.4 (range, 18.0-39.9) kg/m2 in the non-visualized cohort (P = 0.015). CONCLUSIONS: TVS has become an accepted first step in the evaluation of PMB. However, in our cohort, 38.1% of women had anatomical reasons for non-visualization of the endometrium and lack of a reliable endometrial thickness measurement, including fibroids, adenomyosis or an axial uterus. There was no significant difference between groups in the interval from menopause or current use of hormone replacement therapy, but the mean BMI of the non-visualized group was significantly higher than in the visualized group. Clinicians should be cognizant of these potential limitations of TVS in the initial evaluation of women with PMB. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.