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2.
Res Sq ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38645140

RESUMO

Background: Allele-specific expression (ASE) analysis provides a nuanced view of cis-regulatory mechanisms affecting gene expression. Results: An equine ASE analysis was performed, using integrated Iso-seq and short-read RNA sequencing data from four healthy Thoroughbreds (2 mares and 2 stallions) across 9 tissues from the Functional Annotation of Animal Genomes (FAANG) project. Allele expression was quantified by haplotypes from long-read data, with 42,900 allele expression events compared. Within these events, 635 (1.48%) demonstrated ASE, with liver tissue containing the highest proportion. Genetic variants within ASE events were in histone modified regions 64.2% of the time. Validation of allele-specific variants, using a set of 66 equine liver samples from multiple breeds, confirmed that 97% of variants demonstrated ASE. Conclusions: This valuable publicly accessible resource is poised to facilitate investigations into regulatory variation in equine tissues. Our results highlight the tissue-specific nature of allelic imbalance in the equine genome.

4.
Ir J Med Sci ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478182

RESUMO

BACKGROUND: Remediation of underperforming students is recognised as an important tool in medical education; however, there is no universally agreed approach. AIMS: This study aimed to evaluate the effectiveness of a remediation program for final year medical students who failed their first long case assessment (LCA1) and to compare their academic performance with their peers who passed their first long case assessment. METHODS: The study consisted of two phases. Phase 1 analysed the demographics and academic performance data for the 9% of the class in the remediation group. Phase 2 focused on collecting similar data for the remaining 91% of students in the non-remediation group. Statistical analyses including the Wilcoxon rank sum test and Pearson correlation coefficients were used to compare the groups. RESULTS: Phase 1 showed 88% of students who participated in remediation successfully passed the second long case assessment (LCA2); however, 25% of this cohort ultimately failed the academic year due to poor results in other assessments. Phase 2 results revealed that non-remediation group students scored significantly higher in LCA2 (59.71% vs 52.07%, p < 0.001) compared to their remediation counterparts, despite 19% of them failing this assessment. Non-remediation group students consistently outperformed their remediation group counterparts in formative and summative assessments. Overall, 6.25% of the entire class failed the academic year. CONCLUSION: This study demonstrates the need to focus on overall academic performance to identify struggling students rather than one high stakes exam. Most of the students in the remediation programme ultimately passed LCA2.

5.
Geroscience ; 46(3): 2849-2862, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37855863

RESUMO

Genome-wide association studies (GWAS) in long-lived human populations have led to identification of variants associated with Alzheimer's disease and cardiovascular disease, the latter being the most common cause of mortality in people worldwide. In contrast, naturally occurring cancer represents the leading cause of death in pet dogs, and specific breeds like the Golden Retriever (GR) carry up to a 65% cancer-related death rate. We hypothesized that GWAS of long-lived GRs might lead to the identification of genetic variants capable of modifying longevity within this cancer-predisposed breed. A GWAS was performed comparing GR dogs ≥ 14 years to dogs dying prior to age 12 which revealed a significant association to ERBB4, the only member of the epidermal growth factor receptor family capable of serving as both a tumor suppressor gene and an oncogene. No coding variants were identified, however, distinct haplotypes in the 5'UTR were associated with reduced lifespan in two separate populations of GR dogs. When all GR dogs were analyzed together (n = 304), the presence of haplotype 3 was associated with shorter survival (11.8 years vs. 12.8 years, p = 0.024). GRs homozygous for haplotype 3 had the shortest survival, and GRs homozygous for haplotype 1 had the longest survival (11.6 years vs. 13.5 years, p = 0.0008). Sub-analyses revealed that the difference in lifespan for GRs carrying at least 1 copy of haplotype 3 was specific to female dogs (p = 0.009), whereas survival remained significantly different in both male and female GRs homozygous for haplotype 1 or haplotype 3 (p = 0.026 and p = 0.009, respectively). Taken together, these findings implicate a potential role for ERBB4 in GR longevity and provide evidence that within-breed canine lifespan studies could serve as a mechanism to identify favorable or disease-modifying variants important to the axis of aging and cancer.


Assuntos
Longevidade , Neoplasias , Humanos , Masculino , Cães , Animais , Feminino , Longevidade/genética , Regiões 5' não Traduzidas/genética , Estudo de Associação Genômica Ampla , Envelhecimento , Neoplasias/genética , Neoplasias/veterinária , Receptor ErbB-4/genética
6.
BJR Open ; 5(1): 20210063, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37953868

RESUMO

The exposure to alcohol in utero has been known to damage the developing foetus. Foetal alcohol spectrum disorders is an umbrella term that highlights a range of adverse effects linked to alcohol exposure in utero. Multiple studies have shown specific brain abnormalities, including a reduction in brain size, specifically in the deep nuclei and cerebellum, and parietal and temporal lobe white matter changes. While studies ascertained that other prenatal risk factors, such as maternal use of illicit drugs or lack of pre-natal care, and post-natal risk factors, such as physical or sexual abuse and low socioeconomic status, may be involved in the pathology of variances in foetal neurological abnormalities, prenatal alcohol exposure remained the strongest factor for effects on brain structure and function. Particularly, the number of days of alcohol consumption per week and drinking during all three trimesters of the pregnancy indicating the strongest relationship with brain abnormalities. Further studies are needed to explain pre-natal risk factors in isolation as well as in combination for neurodevelopmental outcomes. The diverse phenotypic presentations described indicate that the diagnostic criteria of foetal alcohol spectrum disorder must be refined to better represent the range of neurologic anomalies.

7.
Ear Hear ; 44(5): 1271-1281, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37594255

RESUMO

OBJECTIVES: To understand factors associated with outcomes in a cluster-randomized controlled trial that evaluated a telemedicine specialty referral intervention for school hearing screenings in 15 rural Alaskan communities. DESIGN: Hearing Norton Sound was a mixed methods cluster-randomized controlled trial that compared a telemedicine specialty referral pathway (intervention) to a standard primary care referral pathway (control) for school hearing screenings. As a mixed methods trial, both quantitative and qualitative data were collected, analyzed, and integrated. Main trial results are published elsewhere, but integration of community-specific quantitative outcomes and qualitative results have not yet been reported. The constant comparative method was used to analyze qualitative data from semistructured interviews with six stakeholder groups across all 15 communities. Descriptive statistics were used to describe community-specific proportions of follow-up in both trial years. Qualitative and quantitative results were integrated to reveal relationships between contextual factors and follow-up outcomes across communities. RESULTS: The Hearing Norton Sound trial enrolled 1481 children from October 2017 to March 2019, with a total of 790 children requiring referral. Of the children who referred in the telemedicine specialty referral pathway communities (intervention), 68.5% received follow-up (268/391), compared to 32.1% (128/399) in primary care referral communities (control)(previously reported). When broken down by community, the mean proportion receiving follow-up was 75.26% (SD 22.5) and 37.9% (SD 11.4) for the telemedicine specialty referral communities and primary care referral communities, respectively. For qualitative data collection, semistructured interviews were conducted with 101 individuals between December 2018 and August 2019. Six stakeholder groups participated: elders (n = 14), parents (n = 25), children (n = 11), teachers/school staff (n = 18), principals (n = 6), and healthcare providers/clinic staff (n = 27). Six overall factors related to the outcomes of the telemedicine specialty referral pathway emerged during analysis: clinic capacity, personnel ownership and engagement, scheduling, telemedicine equipment/processes, communication, and awareness of the need for follow-up. We integrated these factors with the community-specific follow-up percentages and found associations for four of the six qualitative factors: clinic capacity, personnel ownership and engagement, communication, and awareness. An association was not seen for scheduling and telemedicine equipment/processes, which had variable relationships with the follow-up outcome. CONCLUSIONS: The Hearing Norton Sound trial demonstrated that a telemedicine specialty referral pathway can close the gap on children lost to follow up after school hearing screening. As a whole, the intervention profoundly increased the proportion of children receiving follow-up, but there was variability in outcomes within and between communities. To understand this variability, we analyzed community-specific intervention outcomes alongside community member feedback on factors related to the intervention. We identified four key factors that contributed to the success of the intervention. Attention to these factors will be essential to successful adaptation and implementation of this telemedicine specialty referral intervention and other similar interventions in future work in rural Alaska and beyond.


Assuntos
Serviços de Saúde Escolar , Telemedicina , Criança , Humanos , Alaska , Testes Auditivos , Encaminhamento e Consulta , Telemedicina/métodos , População Rural , Acessibilidade aos Serviços de Saúde
8.
J Biomol Struct Dyn ; : 1-11, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37572327

RESUMO

Several secreted proteins from helminths (parasitic worms) have been shown to have immunomodulatory activities. Asparaginyl-tRNA synthetases are abundantly secreted in the filarial nematode Brugia malayi (BmAsnRS) and the parasitic flatworm Schistosoma japonicum (SjAsnRS), indicating a possible immune function. The suggestion is supported by BmAsnRS alleviating disease symptoms in a T-cell transfer mouse model of colitis. This immunomodulatory function is potentially related to an N-terminal extension domain present in eukaryotic AsnRS proteins but few structure/function studies have been done on this domain. Here we have determined the three-dimensional solution structure of the N-terminal extension domain of SjAsnRS. A protein containing the 114 N-terminal amino acids of SjAsnRS was recombinantly expressed with isotopic labelling to allow structure determination using 3D NMR spectroscopy, and analysis of dynamics using NMR relaxation experiments. Structural comparisons of the N-terminal extension domain of SjAsnRS with filarial and human homologues highlight a high degree of variability in the ß-hairpin region of these eukaryotic N-AsnRS proteins, but similarities in the disorder of the C-terminal regions. Limitations in PrDOS-based intrinsically disordered region (IDR) model predictions were also evident in this comparison. Empirical structural data such as that presented in our study for N-SjAsnRS will enhance the prediction of sequence-homology based structure modelling and prediction of IDRs in the future.Communicated by Ramaswamy H. Sarma.

9.
Ear Hear ; 44(5): 1078-1087, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36939709

RESUMO

OBJECTIVES: The aim of this study is to present an explanatory model of hearing loss in the Bering Strait region of Alaska in order to contextualize the results of a cluster randomized trial and propose implications for regional hearing-related health care. DESIGN: To promote ecological validity, or the generalizability of trial findings to real world experiences, qualitative methods (focus groups and interviews) were used within a mixed methods cluster randomized trial evaluating school hearing screening and follow-up processes in 15 communities in the Bering Strait region of Alaska. Focus groups were held between April and August 2017, and semistructured interviews were conducted between December 2018 and August 2019. Convenience sampling was used for six of the 11 focus groups to capture broad community feedback. Purposive sampling was used for the remaining five focus groups and for all interviews to capture a variety of experiences with hearing loss. Audio recordings of focus groups and interviews were transcribed, and both notes and transcripts were deidentified. All notes and transcripts were included in the analysis. The constant comparative method was used to develop a codebook by iteratively moving between transcripts and preliminary themes. Researchers then used this codebook to code data from all focus groups and interviews using qualitative analysis software (NVIVO 12, QSR International) and conducted thematic analyses to distill the findings presented in this article. RESULTS: Participants in focus groups (n = 116) and interviews (n = 101) shared perspectives in three domains: etiology, impact, and treatment of hearing loss. Regarding etiology, participants emphasized noise-induced hearing loss but also discussed infection-related hearing loss and various causes of ear infections. Participants described the impact of hearing loss on subsistence activities, while also detailing social, academic, and economic consequences. Participants described burdensome treatment pathways that are repetitive and often travel and time intensive. Communication breakdowns within these pathways were also described. Some participants spoke positively of increased access via onsite hearing health care services in "field clinics" as well as via telemedicine services. Others described weaknesses in these processes (infrequent field clinics and communication delays in telemedicine care pathways). Participants also described home remedies and stigma surrounding the treatment for hearing loss. CONCLUSIONS: Patient-centered health care requires an understanding of context. Explanatory models of illness are context-specific ways in which patients and their networks perceive and describe the experience of an illness or disability. In this study, we documented explanatory models of hearing loss to foster ecological validity and better understand the relevance of research findings to real-life hearing-related experiences. These findings suggest several areas that should be addressed in future implementation of hearing health care interventions elsewhere in rural Alaska, including management of repetitious treatments, awareness of infection-mediated hearing loss, mistrust, and communication breakdowns. For hearing-related health care in this region, these findings suggest localized recommendations for approaches for prevention and treatment. For community-based hearing research, this study offers an example of how qualitative methods can be used to generate ecologically valid (i.e., contextually grounded) findings.


Assuntos
Surdez , Perda Auditiva Provocada por Ruído , Telemedicina , Humanos , Alaska/epidemiologia , Atenção à Saúde , Perda Auditiva Provocada por Ruído/epidemiologia , Pesquisa Qualitativa
10.
J Hum Lact ; 39(2): 245-254, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35730582

RESUMO

BACKGROUND: Supplementation in the newborn nursery has been associated with shorter breastfeeding duration. However, supplementation may at times be necessary. RESEARCH AIM: To determine the association between type of supplementation in the newborn nursery (mother's own milk, formula, donor human milk) and breastfeeding outcomes at 2 and 6 months of age. METHODS: This was a prospective, longitudinal, observational multi-group cohort study. In total, 2,343 surveys were sent to parents who, prior to delivery, indicated intent to exclusively breastfeed. Participants were grouped by type of nursery supplementation. Surveys asked about breastfeeding outcomes when infants were 2 and 6 months old. Our final analytic sample included data from 1,111 healthy newborns ≥ 35 weeks. We used multiple logistic regression to compare future breastfeeding outcomes for infants who were exclusively directly breastfed or who received supplementation during their birth hospitalization. RESULTS: Both the donor human milk and formula groups had decreased breastfeeding at 2 and 6 months compared to the exclusively directly breastfed group. Notably, for infants who received formula compared to donor human milk, the odds of breastfeeding at 2 and 6 months were 74% and 58% lower, respectively (OR = 0.26, 95% CI [0.12, 0.56] at 2 months; OR = 0.42, 95% CI [0.19, 0.94] at 6 months). The donor human milk group had lower odds of breastfeeding at both follow up times compared to the mother's own milk group. CONCLUSION: Among those who intend to breastfeed, supplementation with donor human milk instead of formula in the newborn nursery may support longer breastfeeding.


Assuntos
Aleitamento Materno , Fórmulas Infantis , Lactente , Feminino , Recém-Nascido , Humanos , Estudos de Coortes , Estudos Prospectivos , Leite Humano , Suplementos Nutricionais
11.
Proc Natl Acad Sci U S A ; 119(36): e2202795119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037362

RESUMO

Parasitic helminth infections, while a major cause of neglected tropical disease burden, negatively correlate with the incidence of immune-mediated inflammatory diseases such as inflammatory bowel diseases (IBD). To evade expulsion, helminths have developed sophisticated mechanisms to regulate their host's immune responses. Controlled experimental human helminth infections have been assessed clinically for treating inflammatory conditions; however, such a radical therapeutic modality has challenges. An alternative approach is to harness the immunomodulatory properties within the worm's excretory-secretory (ES) complement, its secretome. Here, we report a biologics discovery and validation pipeline to generate and screen in vivo a recombinant cell-free secretome library of helminth-derived immunomodulatory proteins. We successfully expressed 78 recombinant ES proteins from gastrointestinal hookworms and screened the crude in vitro translation reactions for anti-IBD properties in a mouse model of acute colitis. After statistical filtering and ranking, 20 proteins conferred significant protection against various parameters of colitis. Lead candidates from distinct protein families, including annexins, transthyretins, nematode-specific retinol-binding proteins, and SCP/TAPS were identified. Representative proteins were produced in mammalian cells and further validated, including ex vivo suppression of inflammatory cytokine secretion by T cells from IBD patient colon biopsies. Proteins identified herein offer promise as novel, safe, and mechanistically differentiated biologics for treating the globally increasing burden of inflammatory diseases.


Assuntos
Anti-Inflamatórios , Produtos Biológicos , Colite , Proteínas de Helminto , Doenças Inflamatórias Intestinais , Animais , Anti-Inflamatórios/farmacologia , Produtos Biológicos/farmacologia , Colite/tratamento farmacológico , Proteínas de Helminto/genética , Proteínas de Helminto/farmacologia , Helmintos , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/parasitologia , Camundongos
12.
Trop Med Infect Dis ; 7(7)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35878125

RESUMO

The elimination of lymphatic filariasis (LF) is achieved through repeated mass drug administration (MDA) of anti-filarial medications, which interrupts transmission and prevents new infections. Accurate transmission assessments are critical to deciding when to stop MDA. Current methods for evaluating transmission may be insufficiently sensitive, resulting in post-MDA resurgence. We, therefore, evaluated potential diagnostic testing scenarios for post-MDA surveillance. Data were used from two surveys (a household cluster and a cohort) conducted in an area of Mandalay Region, Myanmar, with ongoing transmission following several rounds of MDA. First, age- and sex-adjusted seroprevalence were estimated for the area using the household survey. Next, three Bayesian networks were built from the combined datasets to compare antigens by immunochromatic testing (ICT) and/or Og4C3 enzyme-linked immunosorbent assay (ELISA) and antibody (Ab) detection methods (Wb123 or Bm14 Ab ELISA). The networks were checked for validity and then used to compare diagnostic testing scenarios. The adjusted prevalence from the household survey for antigen, Wb123 Ab and Bm14 Ab were 4.4% (95% CI 2.6-7.3%), 8.7% (5.96-12.5%) and 20.8% (16.0-26.6%), respectively. For the three networks, the True Skill Statistic and Area Under the Receiver Operating Characteristic Curve for antigen, Wb123 and Bm14 Ab were 0.79, 0.68 and 0.55; and 0.97, 0.92 and 0.80, respectively. In the Bayesian network analysis, a positive case was defined as testing positive to one or more infection markers. A missed result was therefore the probability of a positive case having a negative test result to an alternate marker. The probability of a positive case prior to any testing scenario was 17.4%, 16.8% and 26.6% for antigen, Wb123 Ab and Bm14 Ab, respectively. In the antigen-only testing scenario, the probability of a missed positive LF result was 5.2% for Wb123 and 15.6% for Bm14 Ab. The combination of antigen plus Bm14 Ab testing reduced the probability of missing a positive LF case as measured by Wb123 Ab to 0.88%. The combination of antigen plus Wb123 Ab was less successful and yielded an 11.5% probability of a missed positive result by Bm14 Ab testing. Across scenarios, there was a greater discordance between Bm14 and both antigen and Wb123 Ab in the 1-10 age group compared to older ages. These findings suggest that the addition of Bm14 Ab improves the sensitivity of LF testing for current or past infection. The combination of antigen plus Bm14 Ab should therefore be considered for inclusion in post-MDA surveillance to improve the sensitivity of transmission surveys and prevent the premature cessation of MDA.

13.
Pediatr Blood Cancer ; 69(9): e29693, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35373875

RESUMO

BACKGROUND: Ketamine is an NMDA-receptor antagonist with analgesic and opioid-sparing properties. Although well studied in adults, more robust evidence supporting ketamine's use for pediatric pain management is needed. This retrospective study evaluates ketamine's opioid-sparing effectiveness in pediatric and young adult oncology and hematology patients. PROCEDURE: Continuous ketamine infusions administered for pain management between 2010-2020 were reviewed. Data including demographic characteristics, oncology/hematology and pain diagnoses, concurrent pain medications, and ketamine infusions' dose and duration were collected. Opioid consumption data based on delivery via patient-controlled analgesia were collected 1 day before (D1), all days during (cumulatively named D2), and 1 day after (D3) ketamine infusions and calculated as morphine-equivalent doses (mg/kg/day). Data were reported for the entire study group as well as for distinct oncology and end-of-life categories, and short-term acute pain circumstances which included vaso-occlusive crises in hematology patients. Side effects were reviewed. RESULTS: Significantly lower daily opioid consumption was noted in the oncology group, while decreases were not significant in the end-of-life group and in the overall study population. The acute pain group did not show an opioid reduction associated with the ketamine infusions. A largely tolerable side-effect profile was observed, with no differences among each group's incidence. CONCLUSIONS: Ketamine infusions were associated with significantly reduced opioid consumption for oncology patients. The opioid-sparing effects of ketamine may vary according to clinical diagnoses and circumstances of use. Overall, low-dose ketamine infusions present an acceptable safety profile in pediatric and young adult patients; nevertheless, individual risks and benefits should be considered.


Assuntos
Dor Aguda , Ketamina , Neoplasias , Transtornos Relacionados ao Uso de Opioides , Dor Aguda/tratamento farmacológico , Analgésicos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Criança , Morte , Humanos , Infusões Intravenosas , Ketamina/uso terapêutico , Morfina/uso terapêutico , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Dor Pós-Operatória/induzido quimicamente , Dor Pós-Operatória/tratamento farmacológico , Estudos Retrospectivos , Adulto Jovem
14.
J Clin Med ; 11(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35268460

RESUMO

Mucolipidosis type II (ML II) is an autosomal recessive lysosomal targeting disorder that may present with features of hyperparathyroidism. The aim of this study was to describe in detail the clinical cases of ML II presenting to a tertiary referral centre with biochemical and/or radiological features of hyperparathyroidism. There were twenty-three children diagnosed with ML II in the Republic of Ireland from July 1998 to July 2021 inclusive (a 23-year period). The approximate incidence of ML II in the Republic of Ireland is, therefore, 1 per 64,000 live births. Medical records were available and were reviewed for 21 of the 23 children. Five of these had been identified as having biochemical and/or radiological features of hyperparathyroidism. Of these five, three children were born to Irish Traveller parents and two to non-Traveller Irish parents. All five children had radiological features of hyperparathyroidism (on skeletal survey), with evidence of antenatal fractures in three cases and an acute fracture in one. Four children had biochemical features of secondary hyperparathyroidism. Three children received treatment with high dose Vitamin D supplements and two who had antenatal/acute fractures were managed with minimal handling. We observed resolution of secondary hyperparathyroidism in all cases irrespective of treatment. Four of five children with ML II and hyperparathyroidism died as a result of cardiorespiratory failure at ages ranging from 10 months to 7 years. Biochemical and/or radiological evidence of hyperparathyroidism is commonly identified at presentation of ML II. Further studies are needed to establish the pathophysiology and optimal management of hyperparathyroidism in this cohort. Recognition of this association may improve diagnostic accuracy and management, facilitate family counseling and is also important for natural history data.

15.
Appl Environ Microbiol ; 87(17): e0089521, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34161142

RESUMO

Grasslands represent a critical ecosystem important for global food production, soil carbon storage, and water regulation. Current intensification and expansion practices add to the degradation of grasslands and dramatically increase greenhouse gas emissions and pollution. Thus, new ways to sustain and improve their productivity are needed. Research efforts focus on the plant-leaf microbiome, or phyllosphere, because its microbial members impact ecosystem function by influencing pathogen resistance, plant hormone production, and nutrient availability through processes including nitrogen fixation. However, little is known about grassland phyllospheres and their response to environmental stress. In this study, globally dominant temperate and tropical forage grass species were grown in a greenhouse under current climate conditions and drought conditions that mimic future climate predictions to understand if (i) plant host taxa influence microbial community assembly, (ii) microbial communities respond to drought stress, and (iii) phyllosphere community changes correlate to changes in plant host traits and stress-response strategies. Community analysis using high-resolution sequencing revealed Gammaproteobacteria as the dominant bacterial class, which increased under severe drought stress on both temperate and tropical grasses while overall bacterial community diversity declined. Bacterial community diversity, structure, and response to drought were significantly different between grass species. This community dependence on plant host species correlated with differences in grass species traits, which became more defined under drought stress conditions, suggesting symbiotic evolutionary relationships between plant hosts and their associated microbial community. Further understanding these strategies and the functions microbes provide to plants will help us utilize microbes to promote agricultural and ecosystem productivity in the future. IMPORTANCE Globally important grassland ecosystems are at risk of degradation due to poor management practices compounded by predicted increases in severity and duration of drought over the next century. Finding new ways to support grassland productivity is critical to maintaining their ecological and agricultural benefits. Discerning how grassland microbial communities change in response to climate stress will help us understand how plant-microbe relationships may be useful to sustainably support grasslands in the future. In this study, phyllosphere community diversity and composition were significantly altered under drought conditions. The significance of our research is demonstrating how severe climate stress reduces bacterial community diversity, which previously was directly associated with decreased plant productivity. These findings guide future questions about functional plant-microbe interactions under stress conditions, greatly enhancing our understanding of how bacteria can increase food security by promoting grassland growth and resilience.


Assuntos
Bactérias/isolamento & purificação , Microbiota , Poaceae/microbiologia , Água/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Secas , Ecossistema , Pradaria , Poaceae/classificação , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo , Solo/química , Microbiologia do Solo , Água/análise
16.
Horm Res Paediatr ; 94(1-2): 36-43, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34044405

RESUMO

Scintigraphy using technetium-99m (99mTc) is the gold standard for imaging the thyroid gland in infants with congenital hypothyroidism (CHT) and is the most reliable method of diagnosing an ectopic thyroid gland. One of the limitations of scintigraphy is the possibility that no uptake is detected despite the presence of thyroid tissue, leading to the spurious diagnosis of athyreosis. Thyroid ultrasound is a useful adjunct to detect thyroid tissue in the absence of 99mTc uptake. AIMS: We aimed to describe the incidence of sonographically detectable in situ thyroid glands in infants scintigraphically diagnosed with athyreosis using 99mTc and to describe the clinical characteristics and natural history in these infants. METHODS: The newborn screening records of all infants diagnosed with CHT between 2007 and 2016 were reviewed. Those diagnosed with CHT and athyreosis confirmed on scintigraphy were invited to attend a thyroid ultrasound. RESULTS: Of the 488 infants diagnosed with CHT during the study period, 18/73 (24.6%) infants with absent uptake on scintigraphy had thyroid tissue visualised on ultrasound (3 hypoplastic thyroid glands and 15 eutopic glands). The median serum thyroid-stimulating hormone (TSH) concentration at diagnosis was significantly lower than that in infants with confirmed athyreosis (no gland on ultrasound and no uptake on scintigraphy) (74 vs. 270 mU/L), and median free T4 concentration at diagnosis was higher (11.9 vs. 3.9 pmol/L). Six of 10 (60%) infants with no uptake on scintigraphy but a eutopic gland on ultrasound had transient CHT. CONCLUSION: Absent uptake on scintigraphy in infants with CHT does not rule out a eutopic gland, especially in infants with less elevated TSH concentrations. Clinically, adding thyroid ultrasound to the diagnostic evaluation of infants who have athyreosis on scintigraphy may avoid committing some infants with presumed athyreosis to lifelong levothyroxine treatment.


Assuntos
Hipotireoidismo Congênito/diagnóstico por imagem , Disgenesia da Tireoide/diagnóstico por imagem , Glândula Tireoide/diagnóstico por imagem , Hipotireoidismo Congênito/sangue , Feminino , Humanos , Recém-Nascido , Masculino , Triagem Neonatal , Cintilografia , Disgenesia da Tireoide/sangue , Testes de Função Tireóidea , Tireotropina/sangue , Tiroxina/sangue , Ultrassonografia
17.
Transl Res ; 232: 88-102, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33676036

RESUMO

The symbiotic relationships shared between humans and their gastrointestinal parasites present opportunities to discover novel therapies for inflammatory diseases. A prime example of this phenomenon is the interaction of humans and roundworms such as the hookworm, Necator americanus. Epidemiological observations, animal studies and clinical trials using experimental human hookworm infection show that hookworms can suppress inflammation in a safe and well-tolerated way, and that the key to their immunomodulatory properties lies within their secreted proteome. Herein we describe the identification of 2 netrin domain-containing proteins from the N. americanus secretome, and explore their potential in treating intestinal inflammation in mouse models of ulcerative colitis. One of these proteins, subsequently named Na-AIP-1, was effective at suppressing disease when administered prophylactically in the acute TNBS-induced model of colitis. This protective effect was validated in the more robust CD4 T cell transfer model of chronic colitis, where prophylactic Na-AIP-1 reduced T-cell-dependent type-1 cytokine responses in the intestine and the associated intestinal pathology. Mechanistic studies revealed that depletion of CD11c+ cells abrogated the protective anticolitic effect of Na-AIP-1. Next generation sequencing of colon tissue in the T-cell transfer model of colitis revealed that Na-AIP-1 induced a transcriptomic profile associated with the downregulation of metabolic and signaling pathways involved in type-1 inflammation, notably TNF. Finally, co-culture of Na-AIP-1 with a human monocyte-derived M1 macrophage cell line resulted in significantly reduced secretion of TNF. Na-AIP-1 is now a candidate for clinical development as a novel therapeutic for the treatment of human inflammatory bowel diseases.


Assuntos
Anti-Inflamatórios/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Colite Ulcerativa/prevenção & controle , Proteínas de Helminto/administração & dosagem , Necator americanus/química , Netrinas/administração & dosagem , Animais , Linfócitos T CD4-Positivos/transplante , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/imunologia , Modelos Animais de Doenças , Feminino , Proteínas de Helminto/química , Proteínas de Helminto/genética , Infecções por Uncinaria/metabolismo , Humanos , Masculino , Inibidores de Metaloproteinases de Matriz/química , Camundongos Endogâmicos C57BL , Camundongos Knockout , Netrinas/análise , Proteínas Recombinantes/administração & dosagem
18.
J Inherit Metab Dis ; 44(3): 639-655, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33300147

RESUMO

Since 1972, 18 patients (10 females/8 males) have been detected by newborn bloodspot screening (NBS) with neonatal-onset maple syrup urine disease (MSUD) in Ireland. Patients were stratified into three clusters according to clinical outcome at the time of data collection, including developmental, clinical, and IQ data. A fourth cluster comprised of two early childhood deaths; a third patient died as an adult. We present neuroimaging and electroencephalography together with clinical and biochemical data. Incidence of MSUD (1972-2018) was 1 in 147 975. Overall good clinical outcomes were achieved with 15/18 patients alive and with essentially normal functioning (with only the lowest performing cluster lying beyond a single SD on their full scale intelligence quotient). Molecular genetic analysis revealed genotypes hitherto not reported, including a possible digenic inheritance state for the BCKDHA and DBT genes in one family. Treatment has been based on early implementation of emergency treatment, diet, close monitoring, and even dialysis in the setting of acute metabolic decompensation. A plasma leucine ≥400 µmol/L (outside therapeutic range) was more frequently observed in infancy or during adolescence, possibly due to infections, hormonal changes, or noncompliance. Children require careful management during metabolic decompensations in early childhood, and this represented a key risk period in our cohort. A high level of metabolic control can be achieved through diet with early implementation of a "sick day" regime and, in some cases, dialysis as a rescue therapy. The Irish cohort, despite largely classical phenotypes, achieved good outcomes in the NBS era, underlining the importance of early diagnosis and skilled multidisciplinary team management.


Assuntos
Doença da Urina de Xarope de Bordo/diagnóstico , Doença da Urina de Xarope de Bordo/genética , Adolescente , Criança , Pré-Escolar , Dieta com Restrição de Proteínas , Teste em Amostras de Sangue Seco , Diagnóstico Precoce , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Irlanda , Leucina/sangue , Masculino , Triagem Neonatal/métodos , Fenótipo , Estudos Retrospectivos
19.
Res Involv Engagem ; 6(1): 67, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33292651

RESUMO

Community involvement is important in good research practice. We led a community-based study to improve early detection and treatment of childhood hearing loss in rural Alaska. This study evaluated a cell phone-based hearing screening process and compared a new telemedicine specialty referral pathway to the standard primary care referral pathway. The study included community involvement, engagement, and participation from the very beginning to inform how to best design the trial. We obtained insight and feedback from community members through involvement of a core stakeholder team and through community engagement and participation in focus groups and community events. Feedback received through community involvement and participation influenced the design of the trial at key decision points. Community member guidance shaped the research question, the outcomes to be measured, and the procedures for completing the project, such as participant recruitment. This study offers an example of community involvement, engagement and participation that could be mirrored in future research to maintain the interests of participating communities. Background Effective systems for early identification and treatment of childhood hearing loss are essential in rural Alaska, where data indicate a high prevalence of childhood ear infections and hearing loss. However, loss to follow-up from school hearing screening programs is pervasive. The Hearing Norton Sound study was a mixed methods community randomized controlled trial that was developed to address this gap. The study engaged community members and participants in the design of the trial, including involvement of stakeholders as collaborators. Methods Community engagement and participation in research design occurred through focus groups and through the integration of stakeholders into the study team. Representation was cross-sectoral, involving individuals from multiple levels of the school and health system, as well as community members from each of the 15 communities. Feedback obtained between April 2017 and August 2017 informed the final design of the randomized trial, which began enrollment of children in October 2017 and concluded in March 2019. Results Stakeholder involvement and community participation shaped the design of specific trial elements (research question; comparators; outcomes and measures; telemedicine protocols; and recruitment and retention). Community involvement was strengthened by the use of multiple modalities of involvement and by the positionality of lead stakeholders on the study team. Conclusions This study highlights the effectiveness of multifaceted stakeholder involvement and participation in the design of health research conducted within Alaska Native communities. It offers an example of involvement and reporting that could be mirrored in future research in order to protect and further the interests of the participating community. Trial registration ClinicalTrials.gov, NCT03309553 , First registered 10/9/2017.

20.
J Nat Prod ; 83(11): 3454-3463, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33166137

RESUMO

Marine organisms produce a diverse range of toxins and bioactive peptides to support predation, competition, and defense. The peptide repertoires of stony corals (order Scleractinia) remain relatively understudied despite the presence of tentacles used for predation and defense that are likely to contain a range of bioactive compounds. Here, we show that a tentacle extract from the mushroom coral, Heliofungia actiniformis, contains numerous peptides with a range of molecular weights analogous to venom profiles from species such as cone snails. Using NMR spectroscopy and mass spectrometry we characterized a 12-residue peptide (Hact-1) with a new sequence (GCHYTPFGLICF) and well-defined ß-hairpin structure stabilized by a single disulfide bond. The sequence is encoded within the genome of the coral and expressed in the polyp body tissue. The structure present is common among toxins and venom peptides, but Hact-1 does not show activity against select examples of Gram-positive and Gram-negative bacteria or a range of ion channels, common properties of such peptides. Instead, it appears to have a limited effect on human peripheral blood mononuclear cells, but the ecological function of the peptide remains unknown. The discovery of this peptide from H. actiniformis is likely to be the first of many from this and related species.


Assuntos
Antozoários/química , Antibacterianos/química , Peptídeos/química , Sequência de Aminoácidos , Animais , Antibacterianos/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Peptídeos/farmacologia
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