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1.
New Phytol ; 242(5): 2312-2321, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38561636

ABSTRACT

Across temperate forests, many tree species produce flowers before their leaves emerge. This flower-leaf phenological sequence, known as hysteranthy, is generally described as an adaptation for wind pollination. However, this explanation does not address why hysteranthy is also common in biotically pollinated taxa. We quantified flower-leaf sequence variation in the American plums (Prunus, subg. Prunus sect. Prunocerasus), a clade of insect-pollinated trees, using herbaria specimens and Bayesian hierarchical modeling. We tested two common, but rarely interrogated hypotheses - that hysteranthy confers aridity tolerance and/or pollinator visibility - by modeling the associations between hysteranthy and related traits. To understand how these phenology-trait associations were sensitive to taxonomic scale and flower-leaf sequence classification, we then extended these analyses to all Prunus species in North America. Our findings across two taxonomic levels support the hypotheses that hysteranthy may help temporally partition hydraulic demand to reduce water stress and increase pollinator visibility - thereby reducing selective pressure on inflorescence size. Our results provide foundational insights into the evolution of flower-leaf sequences in the genus Prunus, with implications for understanding these patterns in biotically pollinated plants in general. Our approach suggests a path to advance these hypotheses to other clades, but teasing out drivers fully will require new experiments.


Subject(s)
Flowers , Plant Leaves , Pollination , Prunus , Flowers/physiology , Pollination/physiology , Plant Leaves/physiology , Prunus/physiology , Prunus/genetics , Animals , Bayes Theorem
2.
BMC Infect Dis ; 22(1): 106, 2022 Jan 30.
Article in English | MEDLINE | ID: mdl-35094689

ABSTRACT

INTRODUCTION: The Coronavirus Disease 2019 (COVID-19) pandemic has resulted in a major breakdown of health service provision in the fight against neglected tropical diseases (NTDs). COVID-19 may impact NTDs service delivery in varied ways. As the Ghana NTD programme planned to resume MDA activities, we examined the COVID-19 related perceptions and practices among some community members and frontline health workers for NTD control activities in the country. METHODS: The study was conducted in seven communities in the Ahanta West district of Ghana. This was a qualitative study using in-depth interviews (IDI) and focus group discussions (FGDs) for data collection. Participants were purposively selected from varied backgrounds to represent both beneficiaries and service providers directly involved in NTD programme implementation. Trained and experienced qualitative data collectors conducted the FGD and IDI sessions in the local Twi language, while health worker sessions were conducted in English. Discussions were audio-recorded and transcribed directly into English. Data was analysed using an iterative process. The transcripts were pre-coded using the broad themes, entered into a computer using Microsoft Word, and then imported into the MAXQDA software for thematic content analysis to select relevant representative narratives for presentation. RESULTS: Participants were aware of the COVID-19 pandemic and referred to it appropriately as 'coronavirus', COVID-19, and often as 'the new disease'. Though many respondents could not describe the route of transmission, most of them reported that it is transmitted through touch or sharing of common items. They reported some signs/symptoms like fever, headache and difficulty breathing, and prevention methods like the use of hand sanitiser, washing of hands and sneezing appropriately. Respondents have reported that COVID-19 has negatively affected their daily lives by limiting their movements and therefore work. It also came to light that COVID-19 has also negatively affected the NTD programme implementation, especially mass drug administration (MDA) activities, leading to the postponement of the yearly MDA. The COVID-19 pandemic has negatively affected clinic attendance; people are afraid that they may be tested for COVID-19 at the clinic. CONCLUSION: COVID-19 has negatively affected the NTD programme. Education and the provision of personal protective equipment will be required to build the confidence of frontline care providers including community drug distributors and community members in order to enhance quality service and participation in future MDA activities.


Subject(s)
COVID-19 , Ghana/epidemiology , Health Personnel , Humans , Pandemics , Perception , SARS-CoV-2
3.
Ultrasound Obstet Gynecol ; 60(3): 390-395, 2022 09.
Article in English | MEDLINE | ID: mdl-35837717

ABSTRACT

OBJECTIVE: To assess the performance of the 'separation sign' as a predictor of normal placental separation in a large cohort of women at risk for placenta accreta spectrum (PAS) and in a high-risk subgroup with placenta previa or anterior low-lying placenta and at least one previous Cesarean delivery. METHODS: This was a prospective study of women at risk for PAS referred to a specialist clinic at between 22 and 38 weeks' gestation. All women underwent ultrasound assessment for the presence of the separation sign, which detects the difference in elasticity between the myometrium and the placenta, characterized by different rates of rebound after an ultrasound probe is used to apply pressure over the uteroplacental interface. When the sign is positive, the placenta appears to move relative to the myometrium, leading to the appearance or enhancement of the clear zone. The predictive performance of the separation sign for normal spontaneous placental separation at delivery was assessed. RESULTS: Of the 194 included women, 163 had a positive separation sign, all of whom went on to have normal placental separation at delivery. Of the 24 women with a negative separation sign, three (12.5%) had normal placental separation and 21 (87.5%) were diagnosed with PAS. This yielded a sensitivity of 98.2% (95% CI, 94.8-99.6%) and specificity of 100% (95% CI, 83.9-100%). In the high-risk cohort (n = 35), a positive separation sign remained a reliable predictor of normal placental separation, with a positive predictive value of 100%, sensitivity of 88.9% (95% CI, 65.3-98.6%) and specificity of 100% (95% CI, 80.5-100%). CONCLUSIONS: The separation sign could be a useful tool in women considered to be at risk for PAS, as it can facilitate the prediction of normal placental separation at delivery. This may prevent overtreatment, the associated iatrogenic morbidity and unnecessary allocation of clinical resources. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Abruptio Placentae , Placenta Accreta , Placenta Previa , Female , Humans , Placenta/diagnostic imaging , Placenta Accreta/diagnostic imaging , Placenta Previa/diagnostic imaging , Pregnancy , Prospective Studies , Retrospective Studies , Ultrasonography, Prenatal
4.
Proc Biol Sci ; 288(1946): 20202754, 2021 03 10.
Article in English | MEDLINE | ID: mdl-33653144

ABSTRACT

Humans are rapidly changing the marine environment through a multitude of effects, including increased greenhouse gas emissions resulting in warmer and acidified oceans. Elevated CO2 conditions can cause sensory deficits and altered behaviours in marine organisms, either directly by affecting end organ sensitivity or due to likely alterations in brain chemistry. Previous studies show that auditory-associated behaviours of larval and juvenile fishes can be affected by elevated CO2 (1000 µatm). Here, using auditory evoked potentials (AEP) and micro-computer tomography (microCT) we show that raising juvenile snapper, Chrysophyrs auratus, under predicted future CO2 conditions resulted in significant changes to their hearing ability. Specifically, snapper raised under elevated CO2 conditions had a significant decrease in low frequency (less than 200 Hz) hearing sensitivity. MicroCT demonstrated that these elevated CO2 snapper had sacculus otolith's that were significantly larger and had fluctuating asymmetry, which likely explains the difference in hearing sensitivity. We suggest that elevated CO2 conditions have a dual effect on hearing, directly effecting the sensitivity of the hearing end organs and altering previously described hearing induced behaviours. This is the first time that predicted future CO2 conditions have been empirically linked through modification of auditory anatomy to changes in fish hearing ability. Given the widespread and well-documented impact of elevated CO2 on fish auditory anatomy, predictions of how fish life-history functions dependent on hearing may respond to climate change may need to be reassessed.


Subject(s)
Carbon Dioxide , Seawater , Animals , Fishes , Hearing , Humans , Hydrogen-Ion Concentration , Oceans and Seas
5.
Epidemiol Infect ; 149: e125, 2021 05 07.
Article in English | MEDLINE | ID: mdl-33958017

ABSTRACT

The role of the Eurasian badger (Meles meles) as a wildlife host has complicated the management of bovine tuberculosis (bTB) in cattle. Badger ranging behaviour has previously been found to be altered by culling of badgers and has been suggested to increase the transmission of bTB either among badgers or between badgers and cattle. In 2014, a five-year bTB intervention research project in a 100 km2 area in Northern Ireland was initiated involving selective removal of dual path platform (DPP) VetTB (immunoassay) test positive badgers and vaccination followed by release of DPP test negative badgers ('Test and Vaccinate or Remove'). Home range sizes, based on position data obtained from global positioning system collared badgers, were compared between the first year of the project, where no DPP test positive badgers were removed, and follow-up years 2-4 when DPP test positive badgers were removed. A total of 105 individual badgers were followed over 21 200 collar tracking nights. Using multivariable analyses, neither annual nor monthly home ranges differed significantly in size between years, suggesting they were not significantly altered by the bTB intervention that was applied in the study area.


Subject(s)
Homing Behavior , Mustelidae/physiology , Tuberculosis, Bovine/prevention & control , Animal Culling , Animals , Cattle , Disease Reservoirs/microbiology , Disease Reservoirs/veterinary , Female , Male , Mustelidae/microbiology , Mycobacterium bovis/immunology , Mycobacterium bovis/isolation & purification , Northern Ireland/epidemiology , Tuberculosis, Bovine/diagnosis , Tuberculosis, Bovine/epidemiology , Tuberculosis, Bovine/transmission , Vaccination/veterinary
6.
HIV Med ; 21(10): 617-624, 2020 11.
Article in English | MEDLINE | ID: mdl-32885559

ABSTRACT

BACKGROUND: The European AIDS Clinical Society (EACS) Guidelines cover key aspects of HIV management with major updates every two years. GUIDELINE HIGHLIGHTS: The 2019 Guidelines were extended with a new section focusing on drug-drug interactions and other prescribing issues in people living with HIV (PLWH). The recommendations for treatment-naïve PLWH were updated with four preferred regimens favouring unboosted integrase inhibitors. A two-drug regimen with dolutegravir and lamivudine, and a three-drug regimen including doravirine were also added to the recommended initial regimens. Lower thresholds for hypertension were expanded to all PLWH and for cardiovascular disease prevention, the 10-year predicted risk threshold for consideration of antiretroviral therapy (ART) modification was lowered from 20% to 10%. Frailty and obesity were added as new topics. It was specified to use urine albumin to creatinine ratio to screen for glomerular disease and urine protein to creatinine ratio for tubular diseases, and thresholds were streamlined with the Kidney Disease: Improving Global Outcomes (KDIGO) recommendations. Hepatitis C virus (HCV) treatment recommendations were split into preferred and alternative treatment options. The algorithm for management of recently acquired HCV infection was updated and includes recommendations for early chronic infection management. Treatment of resistant tuberculosis (TB) was streamlined with the World Health Organization (WHO) recommendations, and new tables on immune reconstitution inflammatory syndrome, on when to start ART in the presence of opportunistic infections and on TB drug dosing were included. CONCLUSIONS: The EACS Guidelines underwent major revisions of all sections in 2019. They are available in four different formats including a new interactive web-based version and are translated into Chinese, French, German, Japanese, Portuguese, Russian and Spanish.


Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/drug therapy , HIV Integrase Inhibitors/therapeutic use , Age Factors , Comorbidity , Drug Interactions , Drug Therapy, Combination , Heterocyclic Compounds, 3-Ring/therapeutic use , Humans , Lamivudine/therapeutic use , Oxazines/therapeutic use , Piperazines/therapeutic use , Pyridones/therapeutic use , Treatment Outcome , Triazoles/therapeutic use
7.
AIDS Behav ; 24(6): 1793-1806, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31782068

ABSTRACT

The aim of this study is to investigate five hypothesized mechanisms of causation between depression and condomless sex with ≥ 2 partners (CLS2+) among gay, bisexual, and other men who have sex with men (GBMSM), involving alternative roles of self-efficacy for sexual safety and recreational drug use. Data were from the AURAH cross-sectional study of 1340 GBMSM attending genitourinary medicine clinics in England (2013-2014). Structural equation modelling (SEM) was used to investigate which conceptual model was more consistent with the data. Twelve percent of men reported depression (PHQ-9 ≥ 10) and 32% reported CLS2+ in the past 3 months. AURAH data were more consistent with the model in which depression was considered to lead to CLS2+ indirectly via low self-efficacy for sexual safety (indirect Beta = 0.158; p < 0.001) as well as indirectly via higher levels of recreational drug use (indirect Beta = 0.158; p < 0.001). SEM assists in understanding the relationship between depression and CLS among GBMSM.


Subject(s)
Depression , HIV Infections , Sexual Behavior , Sexual and Gender Minorities , Unsafe Sex , Adolescent , Adult , Condoms , Cross-Sectional Studies , Depression/epidemiology , England/epidemiology , Female , Homosexuality, Male , Humans , Latent Class Analysis , Male , Middle Aged , Risk-Taking , Sexual Partners , Young Adult
8.
Ultrasound Obstet Gynecol ; 54(5): 643-649, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30779235

ABSTRACT

OBJECTIVES: To evaluate fetal growth in pregnancies complicated by placenta previa with or without placenta accreta spectrum (PAS) disorder, compared with in pregnancies with a low-lying placenta. METHODS: This was a multicenter retrospective cohort study of singleton pregnancies complicated by placenta previa with or without PAS disorder, for which maternal characteristics, ultrasound-estimated fetal weight and birth weight were available. Four maternal-fetal medicine units participated in data collection of diagnosis, treatment and outcome. The control group comprised singleton pregnancies with a low-lying placenta (0.5-2 cm from the internal os). The diagnosis of PAS and depth of invasion were confirmed at delivery using both a predefined clinical grading score and histopathological examination. For comparison of pregnancy characteristics and fetal growth parameters, the study groups were matched for smoking status, ethnic origin, fetal sex and gestational age at delivery. RESULTS: The study included 82 women with placenta previa with PAS disorder, subdivided into adherent (n = 35) and invasive (n = 47) PAS subgroups, and 146 women with placenta previa without PAS disorder. There were 64 controls with a low-lying placenta. There was no significant difference in the incidence of small-for-gestational age (SGA) (birth weight ≤ 10th percentile) and large-for-gestational age (LGA) (birth weight ≥ 90th  percentile) between the study groups. Median gestational age at diagnosis was significantly lower in pregnancies with placenta previa without PAS disorder than in the low-lying placenta group (P = 0.002). No significant difference was found between pregnancies complicated by placenta previa with PAS disorder and those without for any of the variables. Median estimated fetal weight percentile was significantly lower in the adherent compared with the invasive previa-PAS subgroup (P = 0.047). Actual birth weight percentile at delivery did not differ significantly between the subgroups (P = 0.804). CONCLUSIONS: No difference was seen in fetal growth in pregnancies complicated by placenta previa with PAS disorder compared with those without and compared with those with a low-lying placenta. There was also no increased incidence of either SGA or LGA neonates in pregnancies with placenta previa and PAS disorder compared with those with placenta previa with spontaneous separation of the placenta at birth. Adverse neonatal outcome in pregnancies complicated by placenta previa and PAS disorder is linked to premature delivery and not to impaired fetal growth. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Subject(s)
Birth Weight , Fetal Development , Placenta Accreta/physiopathology , Placenta Previa/physiopathology , Adult , Case-Control Studies , Female , Humans , Infant, Newborn , Placenta/pathology , Pregnancy , Retrospective Studies , Ultrasonography, Prenatal
9.
BMC Public Health ; 19(1): 905, 2019 Jul 08.
Article in English | MEDLINE | ID: mdl-31286908

ABSTRACT

BACKGROUND: Delay to start antiretroviral therapy (ART) and nonadherence compromise the health and wellbeing of people living with HIV (PLWH), raise the cost of care and increase risk of transmission to sexual partners. To date, interventions to improve adherence to ART have had limited success, perhaps because they have failed to systematically elicit and address both perceptual and practical barriers to adherence. The primary aim of this study is to determine the efficacy of the Supporting UPtake and Adherence (SUPA) intervention. METHODS: This study comprises 2 phases. Phase 1 is an observational cohort study, in which PLWH who are ART naïve and recommended to take ART by their clinician complete a questionnaire assessing their beliefs about ART over 12 months. Phase 2 is a randomised controlled trial (RCT) nested within the observational cohort study to investigate the effectiveness of the SUPA intervention on adherence to ART. PLWH at risk of nonadherence (based on their beliefs about ART) will be recruited and randomised 1:1 to the intervention (SUPA intervention + usual care) and control (usual care) arms. The SUPA intervention involves 4 tailored treatment support sessions delivered by a Research Nurse utilising a collaborative Cognitive Behavioural Therapy (CBT) and Motivational Interviewing (MI) approach. Sessions are tailored to individual needs and preferences based on the individual patient's perceptions and practical barriers to ART. An animation series and intervention manual have been developed to communicate a rationale for the personal necessity for ART and illustrate concerns and potential solutions. The primary outcome is adherence to ART measured using Medication Event Monitoring System (MEMS). Three hundred seventy-two patients will be sufficient to detect a 15% difference in adherence with 80% power and an alpha of 0.05. Costs will be compared between intervention and control groups. Costs will be combined with the primary outcome in cost-effectiveness analyses. Quality adjusted life-years (QALYs) will also be estimated over the follow-up period and used in the analyses. DISCUSSION: The findings will enable patients, healthcare providers and policy makers to make informed decisions about the value of the SUPA intervention. TRIAL REGISTRATION: The trial was retrospectively registered 21/02/2014, ISRCTN35514212 .


Subject(s)
Anti-Retroviral Agents/therapeutic use , Cognitive Behavioral Therapy/methods , HIV Infections/psychology , Motivational Interviewing/methods , Patient Compliance/psychology , Adult , Cognitive Behavioral Therapy/economics , Cohort Studies , Cost-Benefit Analysis , HIV , HIV Infections/drug therapy , HIV Infections/economics , Humans , Male , Motivational Interviewing/economics , Observational Studies as Topic , Quality-Adjusted Life Years , Randomized Controlled Trials as Topic
10.
HIV Med ; 19(10): 724-733, 2018 11.
Article in English | MEDLINE | ID: mdl-30101539

ABSTRACT

OBJECTIVES: The single-tablet regimen rilpivirine, emtricitabine and tenofovir alafenamide (RPV/FTC/TAF) for treatment of HIV-1-infected adults was approved based on bioequivalence. We assessed the clinical efficacy, safety and tolerability of switching to RPV/FTC/TAF from either RPV/FTC/tenofovir disoproxil fumarate (TDF) or efavirenz (EFV)/FTC/TDF. METHODS: We conducted two distinct randomized, double-blind, active-controlled, noninferiority trials in participants taking RPV/FTC/TDF (Study 1216) and EFV/FTC/TDF (Study 1160). Each study randomized virologically suppressed (HIV-1 RNA < 50 copies/mL) adults (1:1) to switch to RPV/FTC/TAF or continue their current regimen for 96 weeks. We evaluated efficacy as the proportion with HIV-1 RNA < 50 copies/mL using the Food and Drug Administration snapshot algorithm and prespecified bone and renal endpoints at week 96. RESULTS: We randomized and treated 630 participants in Study 1216 (RPV/FTC/TAF, n = 316; RPV/FTC/TDF, n = 314) and 875 in Study 1160 (RPV/FTC/TAF, n = 438; EFV/FTC/TDF, n = 437). In both studies, the efficacy of switching to RPV/FTC/TAF was noninferior to that of continuing baseline therapy at week 96, with respective percentages of patients with HIV RNA < 50 copies/mL being 89.2% versus 88.5% in Study 1216 [difference 0.7%; 95% confidence interval (CI) -4.3 to +5.8%] and 85.2% versus 85.1% in Study 1160 (difference 0%; 95% CI -4.8 to +4.8%). No participant on RPV/FTC/TAF developed treatment-emergent resistance versus two on EFV/FTC/TDF and one on RPV/FTC/TDF. Compared with continuing baseline therapy, significant improvements in bone mineral density and renal tubular markers were observed in the RPV/FTC/TAF groups (P < 0.001). CONCLUSIONS: Switching to RPV/FTC/TAF from RPV/FTC/TDF or EFV/FTC/TDF was safe and effective and improved bone mineral density and renal biomarkers up to 96 weeks with no cases of treatment-emergent resistance.


Subject(s)
Anti-Retroviral Agents/administration & dosage , Antiretroviral Therapy, Highly Active/methods , Drug Combinations , Drug Substitution/methods , HIV Infections/drug therapy , Adult , Anti-Retroviral Agents/adverse effects , Antiretroviral Therapy, Highly Active/adverse effects , Double-Blind Method , Drug Substitution/adverse effects , Female , HIV-1/isolation & purification , Humans , Male , Middle Aged , RNA, Viral/blood , Treatment Outcome , Viral Load
11.
BMC Public Health ; 18(1): 238, 2018 02 13.
Article in English | MEDLINE | ID: mdl-29433461

ABSTRACT

BACKGROUND: The Global Program for the Elimination of Lymphatic Filariasis (GPELF) started operation in 2000 and aimed at eliminating the disease by the year 2020, following 5-6 rounds of effective annual Mass Drug Administration (MDA). The MDA programme took off in Ghana in 2001 and has interrupted transmission in many areas while it has persisted in some areas after 10 or more rounds of MDA. This study was to appreciate community members' perspectives on MDA after over 15 years of implementation. Findings will inform strategies to mobilise community members to participate fully in MDA to enhance the disease elimination process. METHODS: This was a qualitative study, employing key-informant in-depth-interviews. Respondents were selected based on their recognition by community members as opinion leaders and persons who were knowledgeable about the topic of interest in the community. A snowball sampling technique was used to select respondents. RESULTS: Respondents were well informed about the MDA with most of them saying, it has been implemented for over 12 years. They were aware that the MDA was for the treatment/control of LF (elephantiasis). It came to light that MDA compliance was affected by five related barriers. These are; Medication, Personal, Health system, Disease and Social structure related barriers. Adverse effects of the drugs and the fact that many people perceived that they were not susceptibility to the infection have grossly affected the ingestion of the drugs. CONCLUSION: There is a need for community mobilization and promotional activities to explain the expected adverse reactions associated with the drugs to the people. Also the importance of why every qualified person in the community must comply with MDA must be emphasized.


Subject(s)
Disease Eradication/methods , Elephantiasis, Filarial/prevention & control , Filaricides/therapeutic use , Health Knowledge, Attitudes, Practice , Mass Drug Administration , Adult , Elephantiasis, Filarial/epidemiology , Female , Ghana/epidemiology , Humans , Male , Middle Aged , Qualitative Research
12.
HIV Med ; 18(2): 73-79, 2017 02.
Article in English | MEDLINE | ID: mdl-27167600

ABSTRACT

OBJECTIVES: Involvement of people living with HIV (PLHIV) in the design of HIV cure studies is important, given the potential risks to participants. We present results of an international survey of PLHIV to define these issues and inform cure research. METHODS: PLHIV were recruited in June-November 2014 through HIV websites, advocacy forums, social media and 12 UK HIV clinics. The survey included questions concerning demographics, HIV disease history, the desirability of types of cure and the patient's willingness to accept potential toxicity and treatment interruption (TI). We examined factors associated with TI and willingness to accept substantial risks. RESULTS: A total of 982 PLHIV completed the survey; 87% were male, 79% white and 81% men who have sex with men (MSM). Fifty-one per cent were aged 25-44 years and 69% were UK residents. The median time since diagnosis was 7 years [interquartile range (IQR) 2-17 years]. Eighty-eight per cent were receiving antiretrovirals (91% reported undetectable viral load). Health/wellbeing improvements (96%) and an inability to transmit HIV (90%) were more desirable cure characteristics than testing HIV-negative (69%). Ninety-five per cent were interested in participating in cure studies, and 59% were willing to accept substantial risks. PLHIV with a low CD4 count [201-350 cells/µL vs. ≥ 350 cells/µL; odds ratio (OR) 2.11; 95% confidence interval (CI) 1.11-4.00] were more likely to accept risks, whereas those with limited knowledge of HIV treatments vs. excellent/good knowledge and those aged ≥ 65 years vs. 45-64 years were less likely to accept risks [OR 0.58 (95% CI 0.37-0.90) and OR 0.18 (95% CI 0.07-0.45), respectively]. TI was acceptable for 62% of participants, with the main concerns being becoming unwell (82%), becoming infectious (76%) and HIV spreading through the body (76%). CONCLUSIONS: Cure research was highly acceptable to the PLHIV surveyed. Most individuals would accept risks, including TI, even in the absence of personal benefit. An optimal cure would improve health and minimize onward transmission risk.


Subject(s)
Attitude , Clinical Trials as Topic , HIV Infections/drug therapy , HIV Infections/psychology , Patient Acceptance of Health Care/psychology , Patient Participation/psychology , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , United Kingdom , Young Adult
13.
HIV Med ; 18(2): 89-103, 2017 02.
Article in English | MEDLINE | ID: mdl-27385511

ABSTRACT

OBJECTIVES: An increasing proportion of people living with HIV are older adults, who may require specialized care. Adverse physical and psychological effects of HIV infection may be greatest among older people or those who have lived longer with HIV. METHODS: The ASTRA study is a cross-sectional questionnaire study of 3258 HIV-diagnosed adults (2248 men who have sex with men, 373 heterosexual men and 637 women) recruited from UK clinics in 2011-2012. Associations of age group with physical symptom distress (significant distress for at least one of 26 symptoms), depression and anxiety symptoms (scores ≥ 10 on PHQ-9 and GAD-7, respectively), and health-related functional problems (problems on at least one of three domains of the Euroqol 5D-3L)) were assessed, adjusting for time with diagnosed HIV infection, gender/sexual orientation and ethnicity. RESULTS: The age distribution of participants was: < 30 years, 5%; 30-39 years, 23%; 40-49 years, 43%; 50-59 years, 22%; and ≥ 60 years, 7%. Overall prevalences were: physical symptom distress, 56%; depression symptoms, 27%; anxiety symptoms, 22%; functional problems, 38%. No trend was found in the prevalence of physical symptom distress with age [adjusted odds ratio (OR) for trend across age groups, 0.96; 95% confidence interval (CI) 0.89, 1.04; P = 0.36]. The prevalence of depression and anxiety symptoms decreased with age [adjusted OR 0.86 (95% CI 0.79, 0.94; P = 0.001) and adjusted OR 0.85 (95% CI 0.77, 0.94; P = 0.001), respectively], while that of functional problems increased (adjusted OR 1.28; 95% CI 1.17, 1.39; P < 0.001). In contrast, a longer time with diagnosed HIV infection was strongly and independently associated with a higher prevalence of symptom distress, depression symptoms, anxiety symptoms, and functional problems (P < 0.001 for trends, adjusted analysis). CONCLUSIONS: Among people living with HIV, although health-related functional problems were more common with older age, physical symptom distress was not, and mental health was more favourable. These results suggest that a longer time with diagnosed HIV infection, rather than age, is the dominating factor contributing to psychological morbidity and lower quality of life.


Subject(s)
Anxiety/epidemiology , Depression/epidemiology , HIV Infections/pathology , HIV Infections/psychology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Time Factors , United Kingdom , Young Adult
14.
HIV Med ; 18(7): 463-473, 2017 08.
Article in English | MEDLINE | ID: mdl-28004523

ABSTRACT

OBJECTIVES: The aim of the study was to assess, among people living with HIV, knowledge of their latest HIV viral load (VL) and CD4 count. METHODS: Agreement between self-report and clinic record was assessed among 2771 HIV-diagnosed individuals on antiretroviral treatment (ART) in the UK Antiretrovirals, Sexual Transmission Risk and Attitudes Study (2011-2012). A confidential self-completed questionnaire collected information on demographic, socioeconomic, HIV-related and health-related factors. Participants were asked to self-report their latest VL [undetectable (≤ 50 copies/mL), detectable (> 50 copies/mL) or "don't know"] and CD4 count (< 200, 200-350, 351-500 or > 500 cells/µL, or "don't know"). Latest clinic-recorded VL and CD4 count were documented. RESULTS: Of 2678 participants on ART, 434 (16.2%) did not accurately report whether their VL was undetectable. Of 2334 participants with clinic-recorded VL ≤ 50 copies/mL, 2061 (88.3%) correctly reported undetectable VL; 49 (2.1%) reported detectable VL; 224 (9.6%) did not know their VL. Of 344 participants with clinic-recorded VL > 50 copies/mL, 183 (53.2%) correctly reported detectable VL; 76 (22.1%) reported undetectable VL; 85 (24.7%) did not know their VL. Of 2137 participants who reported undetectable VL, clinic-recorded VL was ≤ 50 copies/mL for 2061 (96.4%) and <1000 copies/mL for 2122 (99.3%). In analyses adjusted for gender/sexual orientation, ethnicity, age and time since starting ART, factors strongly associated with inaccurate self-report of VL (including "don't know") included socioeconomic disadvantage [prevalence ratio (95% CI) for "not" vs. "always" having enough money for basic needs: 2.4 (1.9, 3.1)], poor English fluency [3.5 (2.4, 5.1) vs. UK born], nondisclosure of HIV status [1.7 (1.3, 2.1)], ART nonadherence [2.1 (1.7, 2.7) for three or more missed doses vs. none in the past 2 weeks] and depressive symptoms (PHQ-9 score ≥ 10) [1.9 (1.6, 2.2)]. Overall, 612 (22.9%) of 2667 participants on ART did not accurately self-report whether or not their CD4 count was ≤ 350 cells/µL. CONCLUSIONS: There is a high level of accuracy of a self-report of undetectable VL in people on ART in the UK. Overall, accurate knowledge of personal VL level varied according to demographic, socioeconomic, HIV-related and health-related factors. Active identification of people who may benefit from increased levels of support and engagement in care is important.


Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/virology , Self Report , Viral Load , Adult , Aged , CD4 Lymphocyte Count , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , United Kingdom , Young Adult
15.
Mol Ecol ; 26(5): 1273-1284, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28100020

ABSTRACT

Several species of swallowtail butterflies (genus Papilio) are Batesian mimics that express multiple mimetic female forms, while the males are monomorphic and nonmimetic. The evolution of such sex-limited mimicry may involve sexual dimorphism arising first and mimicry subsequently. Such a stepwise scenario through a nonmimetic, sexually dimorphic stage has been proposed for two closely related sexually dimorphic species: Papilio phorcas, a nonmimetic species with two female forms, and Papilio dardanus, a female-limited polymorphic mimetic species. Their close relationship indicates that female-limited polymorphism could be a shared derived character of the two species. Here, we present a phylogenomic analysis of the dardanus group using 3964 nuclear loci and whole mitochondrial genomes, showing that they are not sister species and thus that the sexually dimorphic state has arisen independently in the two species. Nonhomology of the female polymorphism in both species is supported by population genetic analysis of engrailed, the presumed mimicry switch locus in P. dardanus. McDonald-Kreitman tests performed on SNPs in engrailed showed the signature of balancing selection in a polymorphic population of P. dardanus, but not in monomorphic populations, nor in the nonmimetic P. phorcas. Hence, the wing polymorphism does not balance polymorphisms in engrailed in P. phorcas. Equally, unlike in P. dardanus, none of the SNPs in P. phorcas engrailed were associated with either female morph. We conclude that sexual dimorphism due to female polymorphism evolved independently in both species from monomorphic, nonmimetic states. While sexual selection may drive male-female dimorphism in nonmimetic species, in mimetic Papilios, natural selection for protection from predators in females is an alternative route to sexual dimorphism.


Subject(s)
Biological Evolution , Butterflies/genetics , Selection, Genetic , Sex Characteristics , Animals , Butterflies/physiology , Female , Genetics, Population , Genome, Insect , Genome, Mitochondrial , Male , Polymorphism, Genetic , Wings, Animal
16.
Phys Rev Lett ; 119(25): 253902, 2017 Dec 22.
Article in English | MEDLINE | ID: mdl-29303339

ABSTRACT

We report the observation of parametrically down-converted x-ray signal photons at photon energies that correspond to idler photons at optical wavelengths. The count-rate dependence on the angles of the input beam and of the detector and on the slit sizes agrees with theory within the experimental uncertainties. The nonlinear susceptibility, which we calculated from the measured efficiencies, is comparable to the nonlinear susceptibility evaluated from the measurements of x-ray and optical wave mixing. The results of the present Letter advance the development of a spectroscopy method for probing valence-electron charges and the microscopic optical response of crystals with atomic-scale resolution.

17.
Phys Rev Lett ; 119(16): 166101, 2017 Oct 20.
Article in English | MEDLINE | ID: mdl-29099194

ABSTRACT

Electron tomography bears promise for widespread determination of the three-dimensional arrangement of atoms in solids. However, it remains unclear whether methods successful for crystals are optimal for amorphous solids. Here, we explore the relative difficulty encountered in atomic-resolution tomography of crystalline and amorphous nanoparticles. We define an informational entropy to reveal the inherent importance of low-entropy zone-axis projections in the reconstruction of crystals. In turn, we propose considerations for optimal sampling for tomography of ordered and disordered materials.

18.
Phys Rev Lett ; 119(16): 167201, 2017 Oct 20.
Article in English | MEDLINE | ID: mdl-29099209

ABSTRACT

We observe and explain theoretically a dramatic evolution of the Dzyaloshinskii-Moriya interaction (DMI) in the series of isostructural weak ferromagnets, MnCO_{3}, FeBO_{3}, CoCO_{3}, and NiCO_{3}. The sign of the interaction is encoded in the phase of the x-ray magnetic diffraction amplitude, observed through interference with resonant quadrupole scattering. We find very good quantitative agreement with first-principles electronic structure calculations, reproducing both sign and magnitude through the series, and propose a simplified "toy model" to explain the change in sign with 3d shell filling. The model gives insight into the evolution of the DMI in Mott and charge transfer insulators.

19.
Phys Rev Lett ; 118(2): 027401, 2017 Jan 13.
Article in English | MEDLINE | ID: mdl-28128616

ABSTRACT

Selective optical excitation of a substrate lattice can drive phase changes across heterointerfaces. This phenomenon is a nonequilibrium analogue of static strain control in heterostructures and may lead to new applications in optically controlled phase change devices. Here, we make use of time-resolved nonresonant and resonant x-ray diffraction to clarify the underlying physics and to separate different microscopic degrees of freedom in space and time. We measure the dynamics of the lattice and that of the charge disproportionation in NdNiO_{3}, when an insulator-metal transition is driven by coherent lattice distortions in the LaAlO_{3} substrate. We find that charge redistribution propagates at supersonic speeds from the interface into the NdNiO_{3} film, followed by a sonic lattice wave. When combined with measurements of magnetic disordering and of the metal-insulator transition, these results establish a hierarchy of events for ultrafast control at complex-oxide heterointerfaces.

20.
Trop Med Int Health ; 22(11): 1451-1456, 2017 11.
Article in English | MEDLINE | ID: mdl-28891597

ABSTRACT

OBJECTIVE: Mass drug administration (MDA) for the control of lymphatic filariasis (LF), in Ghana, started in the year 2000. While this had great success in many implementation units, there remain areas with persistent transmission, after more than 10 years of treatment. A closer examination of the parasite populations could help understand the reasons for persistent infections and formulate appropriate strategies to control LF in these areas of persistent transmission. MATERIALS AND METHODS: In a longitudinal study, we assessed the prevalence of microfilaraemia (mf) in two communities with 12 years of MDA in Ghana. In baseline surveys 6 months after the National MDA in 2014, 370 consenting individuals were tested for antigenaemia using immunochromatographic test (ICT) cards and had their mf count determined through night blood surveys. 48 ICT positives, of whom, 17 were positive for mf, were treated with 400 µg/kg ivermectin + 400 mg albendazole and subsequently followed for parasitological assessment at 3-month intervals for 1 year. This overlapped with the National MDA in 2015. RESULTS: There was a 68% parasite clearance 3 months after treatment. The pre-treatment mf count differed significantly from the post-treatment mf counts at 3 months (P = 0.0023), 6 months (P = 0.0051), 9 months (P = 0.0113) and 12 months (P = 0.0008). CONCLUSION: In these settings with persistent LF transmission, twice-yearly treatment may help accelerate LF elimination. Further large-scale evaluations are required to ascertain these findings.


Subject(s)
Albendazole/therapeutic use , Elephantiasis, Filarial/parasitology , Filaricides/therapeutic use , Filarioidea/growth & development , Ivermectin/therapeutic use , Adolescent , Adult , Aged , Albendazole/pharmacology , Animals , Antigens, Helminth/blood , Child , Elephantiasis, Filarial/blood , Elephantiasis, Filarial/epidemiology , Elephantiasis, Filarial/prevention & control , Female , Filaricides/pharmacology , Filarioidea/drug effects , Ghana/epidemiology , Government Programs , Humans , Ivermectin/pharmacology , Longitudinal Studies , Male , Microfilariae/drug effects , Microfilariae/growth & development , Middle Aged , Prevalence , Young Adult
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