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1.
Curr Issues Personal Psychol ; 12(1): 41-50, 2024.
Article in English | MEDLINE | ID: mdl-38756197

ABSTRACT

BACKGROUND: In Vietnam, research on the impact of parental migration on left-behind children (LBC) has discussed various dimensions of the subject such as subjective well-being, emotional states, social skills, self-esteem and nutrition of LBC. However, there are still gaps in studies on loneliness among LBC in Vietnam. The study aims to explore the status of loneliness in LBC, including associated protective and risk factors, to make suggestions on preventive measures against LBC's loneliness. PARTICIPANTS AND PROCEDURE: The conveniently selected sample includes 439 LBC in 4 Vietnamese provinces: Thai Nguyen, Bac Ninh, Thai Binh and Nghe An. The mean age is 12.73 (SD = 1.68). Female children account for 47.80%. The Children's Loneliness Scale was employed in the study. RESULTS: The total loneliness score of LBC is 28.62 (SD = 9.40), 95% CI: 27.75-29.48. Perceived social support from friends, caregivers and resilience factors of affect control (RAC), family support (RFS) and help-seeking (RHS) are protective factors for loneliness of LBC, with regression coefficient of -.27, -.18, -.11, -.11 and -.09 respectively. CONCLUSIONS: Perceived social support from friends, care-giving attachment and resilience factors of RAC, RFS, and RHS are protective factors for LBC against loneliness. Parents, teachers and guardians are encouraged to have a close connection with LBC, provide adequate care giving; and create a supportive environment for LBC in pursuing healthy peer relationships and train/improve children's skills to strengthen their resilience.

2.
Sci Total Environ ; 929: 172659, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38657809

ABSTRACT

Identifying which environmental drivers underlie degradation and improvements of ecological communities is a fundamental goal of ecology. Achieving this goal is a challenge due to diverse trends in both environmental conditions and ecological communities across regions, and it is constrained by the lack of long-term parallel monitoring of environmental and community data needed to study causal relationships. Here, we identify key environmental drivers using a high-resolution environmental - ecological dataset, an ensemble of the Soil and Water Assessment Tool (SWAT+) model, and ecological models to investigate effects of climate, land-use, and runoff on the decadal trend (2012-2021) of stream macroinvertebrate communities in a restored urban catchment and an impacted catchment with mixed land-uses in Germany. The decadal trends showed decreased precipitation, increased temperature, and reduced anthropogenic land-uses, which led to opposing runoff trends - with decreased runoff in the restored catchment and increased runoff in the impacted catchment. The two catchments also varied in decadal trends of taxonomic and trait composition and metrics. The most significant improvements over time were recorded in communities of the restored catchment sites, which have become wastewater free since 2007 to 2009. Within the restored catchment sites, community metric trends were primarily explained by land-use and evaporation trends, while community composition trends were mostly associated with precipitation and runoff trends. Meanwhile, the communities in the impacted catchment did not undergo significant changes between 2012 and 2021, likely influenced by the effects of prolonged droughts following floods after 2018. The results of our study confirm the significance of restoration and land-use management in fostering long-term improvements in stream communities, while climate change remains a prodigious threat. The coupling of long-term biodiversity monitoring with concurrent sampling of relevant environmental drivers is critical for preventative and restorative management in ecology.


Subject(s)
Environmental Monitoring , Invertebrates , Rivers , Animals , Germany , Climate , Climate Change , Ecosystem , Water Movements
3.
JCEM Case Rep ; 2(2): luae005, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38304007

ABSTRACT

Denosumab-induced hypocalcemia and iron infusion-related hypophosphatemia are both well described. We describe a case of severe hypocalcemia and hypophosphatemia following sequential denosumab and parenteral iron administration. This resulted in respiratory failure due to muscle weakness and cardiac arrhythmia, requiring noninvasive ventilation and urgent intravenous electrolyte replacement. This case highlights the severe dysregulation in calcium and phosphate homeostasis that can occur with denosumab and iron infusions when administered in quick succession. Given that these drugs are among the most common therapies prescribed across a range of specialties, we hope to alert clinicians to this potential serious drug-drug interaction and suggest strategies for monitoring and management of the electrolyte derangement.

4.
Eur J Endocrinol ; 190(2): 182-191, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38064575

ABSTRACT

BACKGROUND: Women with premature ovarian insufficiency (POI) lack oestrogen, which is a key determinant of bone growth, epiphyseal closure, and bone tissue organisation. Although dual-energy X-ray absorptiometry (DXA)-derived areal bone mineral density (BMD) remains the gold standard for fracture risk evaluation, it does not fully characterise the skeletal abnormalities present in these women. Hence, we aimed to assess hip/femur anatomy, strength, and geometry and femoral alignment using advanced hip analysis (AHA). METHODS: We conducted a cross-sectional, case-control study including 89 women with spontaneous normal karyotype POI (s-POI) or iatrogenic POI (i-POI), aged 20-50 years compared with 89 age- and body mass index (BMI)-matched population-based female controls. Hip anatomy, strength, geometrical parameters, and femur alignment were measured using hip DXA images and Lunar AHA software. Femoral orientation angle (FOA) was quantified as the overall orientation of the femur with respect to the axis of the forces transmitted from the upper body. RESULTS: The median age of POI diagnosis was 35 (18-40) years; the mean POI duration at the time of DXA was 2.07 (range 0-13) years, and 84% of POI women received oestrogen therapy. Areal BMD at all sites was significantly lower in the POI group (all P < .05). Indices of compressive and bending strength were lower in women with POI compared with controls, specifically the cross-sectional area (CSA, mm2) and section modulus (SM, mm3) (139.30 ± 29.08 vs 157.29 ± 22.26, P < .001 and 665.21 ± 129.54 vs 575.53 ± 150.88, P < .001, respectively). The FOA was smaller (124.99 ± 3.18) in women with POI as compared with controls (128.04 ± 3.80; P < .001) at baseline and after adjusting for height and femoral neck BMD. CONCLUSION: Alongside lower BMD at multiple sites, the femora of women with POI demonstrate reduced strength and a misalignment with forces transmitted from the upper body. Further research is needed to establish the role of these newly identified features and their role in fracture risk prediction in this population.


Subject(s)
Femur , Fractures, Bone , Female , Humans , Adult , Case-Control Studies , Femur/diagnostic imaging , Femur/anatomy & histology , Bone Density , Absorptiometry, Photon/methods , Estrogens , Femur Neck
5.
JBMR Plus ; 7(2): e10713, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36751414

ABSTRACT

Based on the current paradigm, a healthy bone is one with adequate mass without microarchitectural decay. However, these two features may not be sufficient to ensure that a bone is healthy. In addition, components must be correctly assembled and aligned. This ensures "the right amount of bone, at the right place" and thus, an optimal cohesion or interplay between constituents. Disorganization may be an independent contributor to bone abnormalities including fragility fractures. Indeed, many bone diseases may be characterized by the presence of disorganized bone, including osteogenesis imperfecta, hypophosphatasia, and atypical femur fractures (AFFs). Despite its likely importance, currently, there are no tools to quantify disorganization in vivo. We address this unmet need by describing a novel method for quantifying bone disorganization from X-ray images. Disorganization is quantified as variations in the orientation of bone components in relation to a target reference point. True disorganization created by disarranging (misplacing) pixels within the bone served as "gold standard." To further validate the method in clinical settings, we compared disorganization in three groups of femurs: (i) femurs of women with AFFs (n = 9); (ii) fracture-free femurs contralateral to AFFs (n = 9); and (iii) fracture-free femurs from controls (n = 25). There was excellent agreement between measured disorganization and "gold standard," with R 2 values ranging from 0.84 to 0.99. Precision error ranged from 1.72% to 4.69%. Disorganization produced by abnormalities associated with AFFs was accurately captured. Disorganization level was lowest in fracture-free control femurs, higher in fracture-free contralateral femurs to AFFs, and highest in femurs with AFFs (all p < 0.0001). Quantification of disorganization, a novel biomarker, may provide novel insights into the pathogenesis of metabolic bone diseases beyond that provided by bone mineral density (BMD) or microarchitecture. We provide evidence that measurement of disorganization is likely to help identify patients at risk for fractures, especially in those poorly explained by BMD or microarchitecture such as AFFs. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

7.
JBMR Plus ; 6(8): e10659, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35991532

ABSTRACT

Atypical femur fractures (AFFs) are rare complications of anti-resorptive therapy. Devastating to the affected individual, they pose a public health concern because of reduced uptake of an effective treatment for osteoporosis due to patient concern. The risk of AFF is increased sixfold to sevenfold in patients of Asian ethnicity compared with Europeans. Genetic factors may underlie the AFF phenotype. Given the rarity of AFFs, studying familial AFF cases is valuable in providing insights into any genetic predisposition. We present two Singaporean families, one comprising a mother (1-a) and a daughter (1-b), and the other comprising two sisters (2-a and 2-b). All four cases presented with bisphosphonate-associated AFF. Whole-exome sequencing (WES) was performed on 1-b, 2-a, and 2-b. DNA for 1-a was not available. Variants were examined using a candidate gene approach comprising a list of genes previously associated with AFF in the literature, as well as using unbiased filtering based on dominant and/or recessive inheritance patterns. Using a candidate gene approach, rare variants shared between all three cases were not identified. A rare variant in TMEM25, shared by the two sisters (2-a and 2-b), was identified. A rare heterozygous PLOD2 variant was present in the daughter case with AFF (1-b), but not in the sisters. A list of potential genetic variants for AFF was identified after variant filtering and annotation analysis of the two sisters (2-a and 2-b), including a Gly35Arg variant in TRAF4, a gene required for normal skeletal development. Although the findings from this genetic analysis are inconclusive, a familial aggregation of AFFs is suggestive of a genetic component in AFF pathogenesis. We provide a comprehensive list of rare variants identified in these AFF familial cases to aid future genetic studies. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

8.
Front Endocrinol (Lausanne) ; 13: 860853, 2022.
Article in English | MEDLINE | ID: mdl-35663323

ABSTRACT

Background: Low bone density (BMD) and fractures commonly affect women with premature ovarian insufficiency (POI). However, bone microarchitecture and body composition data are lacking. Objective: To assess and characterise musculoskeletal phenotype and effects of oestrogen replacement therapy (ERT) in women with POI. Method: Cross-sectional and longitudinal studies of 60 normal karyotype women with POI, aged 20-40 years, from 2005-2018. Dual x-ray absorptiometry (DXA)-derived spinal (LS) and femoral neck (FN) BMD, trabecular bone score (TBS), appendicular lean mass (ALM), total fat mass (TFM), and fracture prevalence were compared with 60 age-, and BMI-matched population-based controls. Longitudinal changes in bone and body composition variables and ERT effects were analysed using linear mixed models over a median duration of 6 years. Results: Women with POI were subdivided into spontaneous (s)-POI (n=25) and iatrogenic (i)-POI (n=35). Median(range) age of POI diagnosis was 34 (10-40) years with baseline DXA performed at median 1(0-13) year post-diagnosis. ERT was used by 82% women (similar for both POI groups). FN-BMD were lowest in s-POI (p<0.002). Low TBS was more common in s-POI [(44%), p=0.03], versus other groups. LS-BMD and ALM were lower in both s-POI and i-POI groups than controls (p<0.05). Fracture prevalence was not significantly different: 20% (s-POI), 17% (i-POI), and 8% (controls) (p=0.26). Longitudinal analysis of 23 POI women showed regular ERT was associated with ALM increment of 127.05 g/year (p<0.001) and protected against bone loss. However, ERT interruption was associated with annual reductions in FN BMD and TBS of 0.020g/cm2 and 0.0070 (p<0.05), respectively. Conclusion: Deficits in BMD, trabecular microarchitecture, and lean mass were present in women with POI. However, regular ERT protected against declines in bone variables, with an increase in ALM. Assessment of skeletal and muscle health, and advocating ERT adherence, is essential in POI to optimise musculoskeletal outcomes.


Subject(s)
Fractures, Bone , Primary Ovarian Insufficiency , Absorptiometry, Photon , Bone Density , Cancellous Bone , Cross-Sectional Studies , Estrogen Replacement Therapy , Female , Humans , Male , Primary Ovarian Insufficiency/drug therapy
9.
Viruses ; 14(6)2022 06 15.
Article in English | MEDLINE | ID: mdl-35746782

ABSTRACT

The COVID-19 pandemic has resulted in an unprecedented global demand for in vitro diagnostic reagents. Supply shortages and hoarding have impacted testing capacity which has led to inefficient COVID-19 case identification and transmission control, predominantly in developing countries. Traditionally, RNA extraction is a prerequisite for conducting SARS-CoV-2 nucleic acid amplification tests (NAAT); however, simplified methods of sample processing have been successful at bypassing typical nucleic acid extraction steps, enabling extraction-free SARS-CoV-2 NAAT workflows. These methods involve chemical and physical approaches that are inexpensive and easily accessible alternatives to overcome extraction kit supply shortages, while offering acceptable test performance. Here we provide an overview of three main sample preparation strategies that have been shown to facilitate extraction-free SARS-CoV-2 NAATs.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnosis , COVID-19 Testing , Humans , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , Pandemics , RNA, Viral/genetics , SARS-CoV-2/genetics , Sensitivity and Specificity
10.
Endocr Rev ; 43(2): 240-313, 2022 03 09.
Article in English | MEDLINE | ID: mdl-34476488

ABSTRACT

Osteoporosis is a global public health problem, with fractures contributing to significant morbidity and mortality. Although postmenopausal osteoporosis is most common, up to 30% of postmenopausal women, > 50% of premenopausal women, and between 50% and 80% of men have secondary osteoporosis. Exclusion of secondary causes is important, as treatment of such patients often commences by treating the underlying condition. These are varied but often neglected, ranging from endocrine to chronic inflammatory and genetic conditions. General screening is recommended for all patients with osteoporosis, with advanced investigations reserved for premenopausal women and men aged < 50 years, for older patients in whom classical risk factors for osteoporosis are absent, and for all patients with the lowest bone mass (Z-score ≤ -2). The response of secondary osteoporosis to conventional anti-osteoporosis therapy may be inadequate if the underlying condition is unrecognized and untreated. Bone densitometry, using dual-energy x-ray absorptiometry, may underestimate fracture risk in some chronic diseases, including glucocorticoid-induced osteoporosis, type 2 diabetes, and obesity, and may overestimate fracture risk in others (eg, Turner syndrome). FRAX and trabecular bone score may provide additional information regarding fracture risk in secondary osteoporosis, but their use is limited to adults aged ≥ 40 years and ≥ 50 years, respectively. In addition, FRAX requires adjustment in some chronic conditions, such as glucocorticoid use, type 2 diabetes, and HIV. In most conditions, evidence for antiresorptive or anabolic therapy is limited to increases in bone mass. Current osteoporosis management guidelines also neglect secondary osteoporosis and these existing evidence gaps are discussed.


Subject(s)
Diabetes Mellitus, Type 2 , Fractures, Bone , Osteoporosis , Absorptiometry, Photon/adverse effects , Adult , Bone Density , Diabetes Mellitus, Type 2/complications , Female , Fractures, Bone/etiology , Glucocorticoids , Humans , Male , Osteoporosis/drug therapy , Osteoporosis/epidemiology , Risk Factors
11.
Lancet Glob Health ; 9(5): e610-e619, 2021 05.
Article in English | MEDLINE | ID: mdl-33713630

ABSTRACT

BACKGROUND: Antimicrobial misuse is common in low-income and middle-income countries (LMICs), and this practice is a driver of antibiotic resistance. We compared community-based antibiotic access and use practices across communities in LMICs to identify contextually specific targets for interventions to improve antibiotic use practices. METHODS: We did quantitative and qualitative assessments of antibiotic access and use in six LMICs across Africa (Mozambique, Ghana, and South Africa) and Asia (Bangladesh, Vietnam, and Thailand) over a 2·5-year study period (July 1, 2016-Dec 31, 2018). We did quantitative assessments of community antibiotic access and use through supplier mapping, customer exit interviews, and household surveys. These quantitative assessments were triangulated with qualitative drug supplier and consumer interviews and discussions. FINDINGS: Vietnam and Bangladesh had the largest proportions of non-licensed antibiotic dispensing points. For mild illness, drug stores were the most common point of contact when seeking antibiotics in most countries, except South Africa and Mozambique, where public facilities were most common. Self-medication with antibiotics was found to be widespread in Vietnam (55·2% of antibiotics dispensed without prescription), Bangladesh (45·7%), and Ghana (36·1%), but less so in Mozambique (8·0%), South Africa (1·2%), and Thailand (3·9%). Self-medication was considered to be less time consuming, cheaper, and overall, more convenient than accessing them through health-care facilities. Factors determining where treatment was sought often involved relevant policies, trust in the supplier and the drug, disease severity, and whether the antibiotic was intended for a child. Confusion regarding how to identify oral antibiotics was revealed in both Africa and Asia. INTERPRETATION: Contextual complexities and differences between countries with different incomes, policy frameworks, and cultural norms were revealed. These contextual differences render a single strategy inadequate and instead necessitate context-tailored, integrated intervention packages to improve antibiotic use in LMICs as part of global efforts to combat antibiotic resistance. FUNDING: Wellcome Trust and Volkswagen Foundation.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Drug Misuse/statistics & numerical data , Health Knowledge, Attitudes, Practice , Health Services Accessibility/statistics & numerical data , Africa , Asia , Bangladesh , Developing Countries , Evaluation Studies as Topic , Female , Ghana , Humans , Male , Mozambique , Poverty , Qualitative Research , Residence Characteristics , South Africa , Surveys and Questionnaires , Thailand , Vietnam
12.
Heart Lung Circ ; 30(1): e29-e36, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33132052

ABSTRACT

BACKGROUND: Aortic dilatation and bicuspid aortic valve (BAV) are frequent in Turner syndrome (TS). Due to short stature, aortic size index (ASI)-ascending aortic diameter (AD)/body surface area (BSA)-is used to identify aortic dilatation in TS patients. We sought to: 1) describe echocardiographic findings in the largest cohort of Australian women with TS; 2) assess if ASI progresses differently with age in TS BAV compared to non-syndromic BAV; and 3) determine whether adjustment of AD for body composition may be superior to BSA indexation. METHODS: Transthoracic echocardiography (TTE) data were retrospectively collected on 125 women with TS. Body composition was quantified by dual energy X-ray absorptiometry (DXA) in 60 women within 6 months of baseline TTE. Age-matched females with non-syndromic BAV (n=170) were used as controls for TS patients with BAV. RESULTS: Mean age of TS women was 28±16 years, and mean height and BSA were 141.6±21.7 cm and 1.4±0.4 m2, respectively. Mean AD was 2.5±0.8 cm, and ASI 2.0±0.6 cm/m2. Aortic dilatation (ASI >2.0 cm/m2) was present in 42 (34%) patients. Turner syndrome women with BAV (n=34; 27%) had a larger ASI than those with tri-leaflet AV (2.2±0.4 cm/m2 vs. 1.7±0.3 cm/m2, p<0.001). In the pooled BAV cohort, TS patients had a higher baseline ASI (2.2±0.4 cm/m2 vs. 2.1±0.3 cm/m2, p=0.02) and greater increase in ASI with age (0.21 mm/m2/year vs. 0.10 mm/m2/year, p=0.01) compared to non-syndromic BAV patients. DXA fat-free mass (r=0.33, p=0.01) and lean mass (r=0.32, p=0.02) correlated with AD, as did BSA (r=0.62, p<0.001). CONCLUSION: Turner syndrome women with BAV have a greater degree of baseline aortic dilatation and a twofold faster increase in aortic dimension with age when compared to matched women with non-syndromic BAV. Several DXA-derived body composition parameters correlate with aortic size in TS, however BSA appears to be the most robust method of indexation.


Subject(s)
Aorta/diagnostic imaging , Aortic Aneurysm, Thoracic/etiology , Bicuspid Aortic Valve Disease/complications , Body Composition , Turner Syndrome/complications , Adolescent , Adult , Aged , Aortic Aneurysm, Thoracic/diagnosis , Bicuspid Aortic Valve Disease/diagnosis , Echocardiography , Female , Humans , Male , Middle Aged , Retrospective Studies , Turner Syndrome/diagnosis , Young Adult
13.
Bone ; 135: 115319, 2020 06.
Article in English | MEDLINE | ID: mdl-32179169

ABSTRACT

Asian race, younger age, higher body mass index (BMI) and antiresorptive drugs have all been associated with atypical femur fractures (AFFs). This increased risk of AFF in Asians is important as by 2050, >50% of hip fractures globally will occur in Asia, with an increased demand for antiresorptive drugs being likely. It is also currently unclear whether AFF risk is increased in all Asian subgroups. We therefore aimed to identify the incidence of AFFs in an Australian tertiary hospital, the contribution of ethnic origin to AFF risk, and determine other clinical risk factors for AFF. From January 1, 2009 to December 31, 2017, 97 AFFs (82 complete and 15 incomplete) occurred in 71 individuals in the overall study population of 204,358. Patients with AFF were more likely to be female (88.7% vs 69.1%, p < 0.001) and younger [median (IQR): 74(52-92) years vs 83(75-88) years, p < 0.001] than the "typical" femur fracture group (n = 3330). The cumulative incidence rate of AFF was 4.2 per 100,000 person-years, far lower than for any ICD-10 AM coded "typical" femur fracture (202.9 per 100,000 person-years). Asians were 3.4 (95%CI, 2.1-5.6) times more likely to sustain an AFF than non-Asians, the highest incidence being in those from South East Asian countries (16.6 per 100,000 person years), suggesting differences in risk between Asian countries. In the nested case-control study, bisphosphonate use was an independent association with AFF development. We conclude Asian ethnicity is an important association with AFF in this large Australian cohort.


Subject(s)
Bone Density Conservation Agents , Femoral Fractures , Asian People , Australia/epidemiology , Bone Density Conservation Agents/adverse effects , Case-Control Studies , Diphosphonates/adverse effects , Ethnicity , Female , Femoral Fractures/epidemiology , Femur , Humans , Male
14.
Semin Reprod Med ; 38(4-05): 289-301, 2020 09.
Article in English | MEDLINE | ID: mdl-33784746

ABSTRACT

Accelerated bone loss and muscle loss coexist in women with premature ovarian insufficiency (POI), but there are significant gaps in our understanding of musculoskeletal health in POI. This review describes estrogen signaling in bone and its role in skeletal health and disease. Possible mechanisms contributing to bone loss in different forms of POI and current evidence regarding the utility of available diagnostic tests and therapeutic options are also discussed. A literature review from January 2000 to March 2020 was conducted to identify relevant studies. Women with POI experience significant deterioration in musculoskeletal health due to the loss of protective effects of estrogen. In bone, loss of bone mineral density (BMD) and compromised bone quality result in increased fracture risk; however, tools to assess bone quality such as trabecular bone score (TBS) need to be validated in this population. Timely initiation of HRT is recommended to minimize the deleterious effects of estrogen deficiency on bone in the absence of contraindications; however, the ideal estrogen replacement regimen remains unknown. POI is associated with compromised bone health, regardless of the etiology. Ongoing research is warranted to refine our management strategies to preserve bone health in women with POI.


Subject(s)
Menopause, Premature , Primary Ovarian Insufficiency , Bone Density , Estrogen Replacement Therapy , Estrogens , Female , Humans
15.
Semin Reprod Med ; 38(4-05): 277-288, 2020 09.
Article in English | MEDLINE | ID: mdl-33418593

ABSTRACT

Accelerated bone loss and muscle decline coexist in women with premature ovarian insufficiency (POI), but there are significant gaps in our understanding of musculoskeletal health in POI. This article is the first of a two-part review which describes estrogen signaling in muscle and its role in musculoskeletal health and disease. Current evidence regarding the utility of available diagnostic tests and therapeutic options is also discussed. A literature review from January 2000 to March 2020 was conducted to identify relevant studies. Women with POI experience significant deterioration in musculoskeletal health due to the loss of protective effects of estrogen. In addition to bone loss, muscle decay and dysfunction is now increasingly recognized. Nevertheless, there is a paucity of validated tools to assess muscle parameters. There is a growing need to acknowledge bone-muscle codependence to design new therapies which target both muscle and bone, resulting in improved physical performance and reduced morbidity and mortality. More high-quality research and international collaborations are needed to address the deficiencies in our understanding and management of musculoskeletal health in women with POI.


Subject(s)
Menopause, Premature , Primary Ovarian Insufficiency , Estrogens , Female , Humans , Muscles
16.
Expert Opin Drug Discov ; 15(4): 415-425, 2020 04.
Article in English | MEDLINE | ID: mdl-31870185

ABSTRACT

Introduction: Bromodomains (BRDs) bind to acetylated lysine residues, often on histones. The BRD proteins can contribute to gene regulation either directly through enzymatic activity or indirectly through recruitment of chromatin-modifying complexes or transcription factors. There is no evidence of direct orthologues of the Plasmodium falciparum BRD proteins (PfBDPs) outside the apicomplexans. PfBDPs are expressed during the parasite's life cycle in both the human host's blood and in the mosquito. PfBDPs could also prove to be promising targets for novel antimalarials, which are urgently required to address increasing drug resistance.Areas covered: This review discusses recent studies of the biology of PfBDPs, current target-based strategies for PfBDP inhibitor discovery, and different approaches to the important step of validating the specificity of hit compounds for PfBDPs.Expert opinion: The novelty of Plasmodium BRDs suggests that they could be targeted by selective compounds. Chemical series that showed promise in screens against human BRDs could be leveraged to create targeted compound libraries, as could hits from P. falciparum phenotypic screens. These targeted libraries and hits could be screened in target-based strategies aimed at discovery and optimization of novel inhibitors of PfBDPs. A key task for the field is to generate parasite assays to validate the hit compounds' specificity for PfBDPs.


Subject(s)
Antimalarials/pharmacology , Malaria, Falciparum/drug therapy , Plasmodium falciparum/drug effects , Animals , Drug Design , Drug Discovery , Drug Resistance , Humans , Malaria, Falciparum/parasitology , Protozoan Proteins/antagonists & inhibitors
17.
Clin Endocrinol (Oxf) ; 91(4): 498-507, 2019 10.
Article in English | MEDLINE | ID: mdl-31218708

ABSTRACT

OBJECTIVE: Osteoporosis associated with premature ovarian insufficiency (POI) and early menopause (EM) is a major concern for women. We aimed to (a) identify information and knowledge gaps and behaviours regarding bone health in women with POI/EM and (b) co-design an osteoporosis fact sheet. DESIGN: Mixed-methods study: survey of women and online resource appraisals to develop and refine, using semi-structured interviews, an osteoporosis fact sheet. PATIENTS: Women with POI/EM (menopause before ages 40 and 45 years respectively). MEASUREMENTS: Demographics, comorbidities, information needs, calcium intake, exercise, osteoporosis knowledge (OKAT), beliefs and self-efficacy, DISCERN appraisal (validated scales). ANALYSIS: descriptive statistics, logistic regression and thematic analysis of interviews. RESULTS: Median age of survey respondents (n = 316) was 54(IQR47-63) years, median age of menopause was 40(IQR38-43) years, and osteoporosis diagnosis was reported in 19%. Most reported inadequate dietary calcium intake (99%) and exercise (65%). Median OKAT score 8 [IQR6-10]/19 indicated knowledge gaps regarding risk factors and treatment options. Adjusting for age and education, OKAT predicted calcium intake (OR 1.126 [CI 1.035-1.225]; P = 0.006) and screening (OR 1.186 [CI 1.077-1.305]; P = 0.001); beliefs predicted screening (OR 1.027 [CI 1.004-1.050]; P = 0.019); and self-efficacy predicted calcium intake (OR1.040 (CI 1.013-1.069); P = 0.003] and exercise (OR 1.117 [CI 1.077-1.160]; P < 0.001). Current online resources have deficiencies. Five themes identified from two interview rounds (n = 10/ round) were as follows: content, emotional response, design, perceived usefulness and clinical considerations. The final fact sheet was considered acceptable and useful in addressing knowledge gaps, promoting information-seeking, impacting behaviours and facilitating healthcare discussions. CONCLUSION: A co-designed fact sheet is acceptable and addresses identified osteoporosis knowledge gaps in women with POI/EM.


Subject(s)
Menopause, Premature/metabolism , Menopause, Premature/physiology , Osteoporosis/diagnosis , Osteoporosis/metabolism , Primary Ovarian Insufficiency/metabolism , Primary Ovarian Insufficiency/physiopathology , Adult , Exercise/physiology , Female , Humans , Logistic Models , Middle Aged , Risk Factors
18.
JBMR Plus ; 2(1): 1-11, 2018 01.
Article in English | MEDLINE | ID: mdl-30283886

ABSTRACT

Atypical femoral fractures (AFFs) are uncommon and have been associated particularly with long-term antiresorptive therapy, including bisphosphonates. Although the pathogenesis of AFFs is unknown, their identification in bisphosphonate-naïve individuals and in monogenetic bone disorders has led to the hypothesis that genetic factors predispose to AFF. Our aim was to review and summarize the evidence for genetic factors in individuals with AFF. We conducted structured literature searches and hand-searching of conference abstracts/reference lists for key words relating to AFF and identified 2566 citations. Two individuals independently reviewed citations for (i) cases of AFF in monogenetic bone diseases and (ii) genetic studies in individuals with AFF. AFFs were reported in 23 individuals with the following 7 monogenetic bone disorders (gene): osteogenesis imperfecta (COL1A1/COL1A2), pycnodysostosis (CTSK), hypophosphatasia (ALPL), X-linked osteoporosis (PLS3), osteopetrosis, X-linked hypophosphatemia (PHEX), and osteoporosis pseudoglioma syndrome (LRP5). In 8 cases (35%), the monogenetic bone disorder was uncovered after the AFF occurred. Cases of bisphosphonate-naïve AFF were reported in pycnodysostosis, hypophosphatasia, osteopetrosis, X-linked hypophosphatemia, and osteoporosis pseudoglioma syndrome. A pilot study in 13 AFF patients and 268 controls identified a greater number of rare variants in AFF cases using exon array analysis. A whole-exome sequencing study in 3 sisters with AFFs showed, among 37 shared genetic variants, a p.Asp188Tyr mutation in the GGPS1 gene in the mevalonate pathway, critical to osteoclast function, which is also inhibited by bisphosphonates. Two studies completed targeted ALPL gene sequencing, an ALPL heterozygous mutation was found in 1 case of a cohort of 11 AFFs, whereas the second study comprising 10 AFF cases did not find mutations in ALPL. Targeted sequencing of ALPL, COL1A1, COL1A2, and SOX9 genes in 5 cases of AFF identified a variant in COL1A2 in 1 case. These findings suggest a genetic susceptibility for AFFs. A large multicenter collaborative study of well-phenotyped AFF cases and controls is needed to understand the role of genetics in this uncommon condition.

19.
J Clin Endocrinol Metab ; 103(10): 3792-3800, 2018 10 01.
Article in English | MEDLINE | ID: mdl-30020460

ABSTRACT

Context: Turner syndrome (TS) is associated with short stature, gonadal failure, and fractures. Spinal trabecular bone score (TBS) is a novel bone imaging modality that has not been evaluated in TS. Objective: To evaluate TBS in TS and its association with bone mineral density (BMD), prevalent fracture, and risk factors. Design and Setting: Longitudinal study of TS from a single tertiary hospital between 2006 and 2017. Patients or Other Participants: Fifty-eight subjects with TS aged 20 to 49 years who underwent dual-energy X-ray absorptiometry (DXA). Main Outcome Measures: TBS, DXA parameters, and prevalent fractures were investigated. Results: Normal, partially degraded, and degraded TBSs were observed in 39 (67%), 15 (26%), and four (7%) subjects, respectively. High rates of prescribed estrogen replacement therapy (ERT) with stable TBS and BMD were observed during follow-up. TBS was positively correlated with spine and femoral neck (FN) BMD and Z-scores (all P < 0.05) and negatively correlated with age (-0.004 per year; P = 0.014) and delay in ERT initiation in women with primary amenorrhea (-0.010 per year; P < 0.001). Fractures were present in 17 (31%) subjects. Low TBS had a significantly higher area under the receiver operator curve for predicting prevalent fracture than low bone mass at either the spine or FN (P < 0.05). Subjects with no history of fracture were more likely to have a normal TBS (P = 0.023). Conclusions: BMD and TBS can be preserved with early initiation and continued use of ERT. TBS may provide additional fracture risk prediction to standard DXA parameters in TS and needs to be validated in larger prospective studies.


Subject(s)
Bone Density , Cancellous Bone/physiopathology , Osteoporosis/diagnosis , Osteoporotic Fractures/diagnosis , Spinal Fractures/diagnosis , Turner Syndrome/complications , Adult , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Longitudinal Studies , Middle Aged , Osteoporosis/etiology , Osteoporosis/physiopathology , Osteoporotic Fractures/etiology , Osteoporotic Fractures/physiopathology , Prognosis , Spinal Fractures/etiology , Spinal Fractures/physiopathology , Young Adult
20.
PLoS Biol ; 16(3): e2004328, 2018 03.
Article in English | MEDLINE | ID: mdl-29529020

ABSTRACT

Within the human host, the malaria parasite Plasmodium falciparum is exposed to multiple selection pressures. The host environment changes dramatically in severe malaria, but the extent to which the parasite responds to-or is selected by-this environment remains unclear. From previous studies, the parasites that cause severe malaria appear to increase expression of a restricted but poorly defined subset of the PfEMP1 variant, surface antigens. PfEMP1s are major targets of protective immunity. Here, we used RNA sequencing (RNAseq) to analyse gene expression in 44 parasite isolates that caused severe and uncomplicated malaria in Papuan patients. The transcriptomes of 19 parasite isolates associated with severe malaria indicated that these parasites had decreased glycolysis without activation of compensatory pathways; altered chromatin structure and probably transcriptional regulation through decreased histone methylation; reduced surface expression of PfEMP1; and down-regulated expression of multiple chaperone proteins. Our RNAseq also identified novel associations between disease severity and PfEMP1 transcripts, domains, and smaller sequence segments and also confirmed all previously reported associations between expressed PfEMP1 sequences and severe disease. These findings will inform efforts to identify vaccine targets for severe malaria and also indicate how parasites adapt to-or are selected by-the host environment in severe malaria.


Subject(s)
Antigens, Protozoan/genetics , Antigens, Surface/genetics , Malaria/parasitology , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Transcriptome , Gene Expression Regulation , Humans , Malaria/pathology , Plasmodium falciparum/isolation & purification , Plasmodium falciparum/metabolism , Sequence Analysis, RNA
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