47 research outputs found
Zebrafish: a vertebrate tool for studying basal body biogenesis, structure, and function.
Understanding the role of basal bodies (BBs) during development and disease has been largely overshadowed by research into the function of the cilium. Although these two organelles are closely associated, they have specific roles to complete for successful cellular development. Appropriate development and function of the BB are fundamental for cilia function. Indeed, there are a growing number of human genetic diseases affecting ciliary development, known collectively as the ciliopathies. Accumulating evidence suggests that BBs establish cell polarity, direct ciliogenesis, and provide docking sites for proteins required within the ciliary axoneme. Major contributions to our knowledge of BB structure and function have been provided by studies in flagellated or ciliated unicellular eukaryotic organisms, specifically Tetrahymena and Chlamydomonas. Reproducing these and other findings in vertebrates has required animal in vivo models. Zebrafish have fast become one of the primary organisms of choice for modeling vertebrate functional genetics. Rapid ex-utero development, proficient egg laying, ease of genetic manipulation, and affordability make zebrafish an attractive vertebrate research tool. Furthermore, zebrafish share over 80 % of disease causing genes with humans. In this article, we discuss the merits of using zebrafish to study BB functional genetics, review current knowledge of zebrafish BB ultrastructure and mechanisms of function, and consider the outlook for future zebrafish-based BB studies
Quality of life and wellbeing among HIV outpatients in East Africa: a multicentre observational study
The development and cognitive testing of the positive outcomes HIV PROM: a brief novel patient-reported outcome measure for adults living with HIV
Background
People living with HIV experience burdensome multidimensional symptoms and concerns requiring person-centred care. Routine use of patient reported outcome measures can improve outcomes. There is no brief patient reported outcome measure (PROM) that currently reflects the breadth of concerns for people living with HIV. This study aimed to develop and cognitively test a brief novel patient reported outcome measure for use within routine adult HIV care– the “Positive Outcomes” HIV PROM.
Methods
Development followed the COSMIN taxonomy and guidance for relevance and comprehensiveness, and Rothrock guidance on development of valid patient reported outcome measures. The Positive Outcomes HIV PROM was developed by a steering group (people living with HIV, HIV professionals and health services researchers) using findings from a previously reported qualitative study of priority outcomes for people living with HIV. The prototype measure was cognitively tested with a purposive sample of people living with HIV.
Results
The Positive Outcomes HIV PROM consists of 23 questions (22 structured, and one open question) informed by the priorities of key stakeholders (n = 28 people living with HIV, n = 21 HIV professionals and n = 8 HIV commissioners) to ensure face and content validity, and refined through cognitive testing (n = 6 people living with HIV). Cognitive testing demonstrated high levels of acceptability and accessibility.
Conclusions
The Positive Outcomes HIV PROM is the first brief patient reported outcome measure reflecting the diverse needs of people living with HIV designed specifically for use in the clinical setting to support patient assessment and care, and drive service quality improvement. It is derived from primary data on the priority outcomes for people living with HIV and is comprehensive and acceptable. Further psychometric testing is required to ensure reliability and responsiveness
Towards person‐centred care for people living with HIV: what core outcomes matter, and how might we assess them? A cross‐national multi‐centre qualitative study with key stakeholders
ObjectivesPeople living with HIV (PLWH) have multidimensional concerns requiring person‐centred care. Routine use of patient‐reported outcome measures (PROMs) improves outcomes. No brief PROM currently reflects the breadth of concerns for PLWH. This study sought to identify priority outcomes for PLWH, model current practice, explore views on introducing PROMs into routine care, and devise a model for person‐centred care incorporating the PROM.MethodsA cross‐national multi‐centre study (London, Brighton and Dublin) was carried out. Semi‐structured qualitative interviews with adult PLWH, HIV health care professionals and HIV commissioners (responsible for planning and commissioning services) were performed. Interviews were analysed using thematic and framework analysis.ResultsPLWH (n = 28), professionals (n = 21) and commissioners (n = 8) described concerns related to living with HIV across six domains: physical (e.g. pain and gastrointestinal symptoms), cognitive (e.g. memory and sleep), psychological (e.g. anxiety and depression), social (e.g. isolation and intimacy), welfare (e.g. finances and fears regarding change of immigration status), and information (e.g. long‐term outcomes) needs. Themes were highly inter‐related, impacting across domains of need (e.g. physical and cognitive problems impacting on psychological and social wellbeing). Perceived benefits of using PROMs in routine HIV care included improved person‐centredness, patient empowerment, fewer missed concerns, increased engagement with services, and informed planning of services. Potential challenges included heterogeneity of PLWH, literacy, and utility for those who struggle to engage with care.ConclusionsThis study presents a novel model of person‐centred care incorporating an HIV‐specific PROM. The model reflects priorities of key stakeholders. Explicit use of PROMs in routine HIV care could afford benefits for PLWH, clinical teams and commissioners
The Neurokinin 1 Receptor Antagonist, Ezlopitant, Reduces Appetitive Responding for Sucrose and Ethanol
Abstract Background: The current obesity epidemic is thought to be partly driven by over-consumption of sugar-sweetened diets and soft drinks. Loss-of-control over eating and addiction to drugs of abuse share overlapping brain mechanisms including changes in motivational drive, such that stimuli that are often no longer ‘liked’ are still intensely ‘wanted’ [7,8]. The neurokinin 1 (NK1) receptor system has been implicated in both learned appetitive behaviors and addiction to alcohol and opioids; however, its role in natural reward seeking remains unknown. Methodology/Principal Findings: We sought to determine whether the NK1-receptor system plays a role in the reinforcing properties of sucrose using a novel selective and clinically safe NK1-receptor antagonist, ezlopitant (CJ-11,974), in three animal models of sucrose consumption and seeking. Furthermore, we compared the effect of ezlopitant on ethanol consumption and seeking in rodents. The NK1-receptor antagonist, ezlopitant decreased appetitive responding for sucrose more potently than for ethanol using an operant self-administration protocol without affecting general locomotor activity. To further evaluate the selectivity of the NK1-receptor antagonist in decreasing consumption of sweetened solutions, we compared the effects of ezlopitant on water, saccharin-, and sodium chloride (NaCl) solution consumption. Ezlopitant decreased intake of saccharin but had no effect on water or salty solution consumption. Conclusions/Significance: The present study indicates that the NK1-receptor may be a part of a common pathway regulating the self-administration, motivational and reinforcing aspects of sweetened solutions, regardless of caloric value, and those of substances of abuse. Additionally, these results indicate that the NK1-receptor system may serve as a therapeutic target for obesity induced by over-consumption of natural reinforcers
Trachoma Prevalence and Associated Risk Factors in The Gambia and Tanzania: Baseline Results of a Cluster Randomised Controlled Trial
Trachoma is caused by Chlamydia trachomatis and is the leading infectious cause of blindness. The World Health Organization's (WHO) control strategy includes antibiotic treatment of all community members, facial cleanliness, and environmental improvements. By determining how prevalent trachoma is, decisions can be made whether control activities need to be put in place. Knowing what factors make people more at risk of having trachoma can help target trachoma control efforts to those most at risk. We looked at the prevalence of active trachoma and C. trachomatis infection in the eyes of children aged 0–5 years in The Gambia and Tanzania. We also measured risk factors associated with having active trachoma or infection. The prevalence of both active trachoma and infection was lower in The Gambia (6.7% and 0.8%, respectively) than in Tanzania (32.3% and 21.9%, respectively). Risk factors for active trachoma were similar in the two countries. For infection, the risk factors in Tanzania were similar to those for TF, whereas in The Gambia, only ocular discharge was associated with infection. These results show that although the prevalence of active trachoma and infection is very different between the two countries, the risk factors for active trachoma are similar but those for infection are different
Digital ulcers in SSc treated with oral treprostinil: A randomized, double-blind, placebo-controlled study with open-label follow-up
Background
Prostacyclins are routinely used to treat vascular features of systemic sclerosis (SSc, scleroderma) but require parenteral infusion or inhalation. This study evaluated the safety and efficacy of oral treprostinil in digital ulcers secondary to SSc.
Methods
This was a randomized (1:1) placebo-controlled, multicenter study in adults with SSc and at least one active digital ulcer at entry. Oral treprostinil was administered twice daily and titrated to maximum tolerated dose with clinical assessments at Weeks 5, 10, 15 and 20. The primary endpoint was change in net digital ulcer burden. Secondary outcomes included ulcer healing and prevention, measures of hand function, quality of life, Raynaud phenomenon and global assessments. Simplified data were gathered during open-label follow up.
Results
Enrolled were 147 patients (109F/38M), mean age 48.8 years with SSc of mean duration 10.5 years. At week 20, mean net ulcer burden was reduced −0.43 ulcers on treprostinil (1.80 vs. 1.37) and −0.10 ulcers on placebo (1.61 vs. 1.51; p = 0.20). There were no effects on ulcer healing or prevention, and small, inconsistent effects on Raynaud phenomenon, global assessment, hand function and quality-of-life measures. In open-label follow-up, there was a continued, small reduction in net ulcer burden (-0.52 month 3, n = 104; −0.64 month 12, n = 36). Common adverse effects were headache, nausea, diarrhea, jaw pain, flushing and other gastrointestinal symptoms.
Conclusions
Administration of oral treprostinil twice daily over 20 weeks was associated with small and statistically insignificant reduction in net ulcer burden in comparison to placebo
Targeting histone deacetyalses in the treatment of B- and T-cell malignancies
HDAC inhibitors (HDACI) are now emerging as one of the most promising new classes of drugs for the treatment of select forms of non-Hodgkin’s lymphoma (NHL). They are particularly active in T-cell lymphomas, possibly hodgkin’s lymphoma and indolent B cell lymphomas. Presently, two of these agents, vorinostat and romidepsin, have been approved in the US for the treatment of relapsed and refractory cutaneous T cell lymphomas (CTCL). Initially, these agents were developed with the idea that they affected transcriptional activation and thus gene expression, by modulating chromatin condensation and decondensation. It is now clear that their effects go beyond chromatin and by affecting the acetylation status of histones and other intra-cellular proteins, they modify gene expression and cellular function via multiple pathways. Gene expression profiles and functional genetic analysis has led to further understanding of the various molecular pathways that are affected by these agents including cell cycle regulation, pathways of cellular proliferation, apoptosis and angiogenesis all important in lymphomagenesis. There is also increasing data to support the effects of these agents on T cell receptor and immune function which may explain the high level of activity of these agents in T cell lymphomas and hodgkin’s lymphoma. There is ample evidence of epigenetic dysregulation in lymphomas which may underlie the mechanisms of action of these agents but how these agents work is still not clear. Current HDAC inhibitors can be divided into at least four classes based on their chemical structure. At present several of these HDAC inhibitors are in clinical trials both as single agents and in combination with chemotherapy or other biological agents. They are easy to administer and are generally well tolerated with minimal side effects. Different dosing levels and schedules and the use of isospecific HDAC inhibitors are some of the strategies that are being employed to increase the therapeutic effect of these agents in the treatment of lymphomas. There may also be class differences that translate into specific activity against different lymphoma. HDAC inhibitors will likely be incorporated into combinations of targeted therapies both in the upfront and relapsed setting for lymphomas
Genomic reconstruction of the SARS-CoV-2 epidemic in England.
The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021
Characteristics of latrines in central Tanzania and their relation to fly catches.
The disposal of human excreta in latrines is an important step in reducing the transmission of diarrhoeal diseases. However, in latrines, flies can access the latrine contents and serve as a mechanical transmitter of diarrhoeal pathogens. Furthermore, the latrine contents can be used as a breeding site for flies, which may further contribute to disease transmission. Latrines do not all produce flies, and there are some which produce only a few, while others can produce thousands. In order to understand the role of the latrine in determining this productivity, a pilot study was conducted, in which fifty latrines were observed in and around Ifakara, Tanzania. The characteristics of the latrine superstructure, use of the latrine, and chemical characteristics of pit latrine contents were compared to the numbers of flies collected in an exit trap placed over the drop hole in the latrine. Absence of a roof was found to have a significant positive association (t=3.17, p=0.003) with the total number of flies collected, and temporary superstructures, particularly as opposed to brick superstructures (z=4.26, p<0.001), and increased total solids in pit latrines (z=2.57, p=0.01) were significantly associated with increased numbers of blowflies leaving the latrine. The number of larvae per gram was significantly associated with the village from which samples were taken, with the largest difference between two villages outside Ifakara (z=2.12, p=0.03). The effect of latrine superstructure (roof, walls) on fly production may indicate that improvements in latrine construction could result in decreases in fly populations in areas where they transmit diarrhoeal pathogens
