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1.
Syst Rev ; 10(1): 289, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34724980

ABSTRACT

BACKGROUND: The coronavirus disease 19 (covid-19) pandemic has underscored the need to expedite clinical research, which may lead investigators to shift away from measuring patient-important outcomes (PIO), limiting research applicability. We aim to investigate if randomized controlled trials (RCTs) of covid-19 pharmacological therapies include PIOs. METHODS: We will perform a meta-epidemiological study of RCTs that included people at risk for, or with suspected, probable, or confirmed covid-19, examining any pharmacological treatment or blood product aimed at prophylaxis or treatment. We will obtain data from all RCTs identified in a living network metanalysis (NMA). The main data sources are the living WHO covid-19 database up to 1 March 2021 and six additional Chinese databases up to 20 February 2021. Two reviewers independently will review each citation, full-text article, and abstract data. To categorize the outcomes according to their importance to patients, we will adapt a previously defined hierarchy: a) mortality, b) quality of life/ functional status/symptoms, c) morbidity, and d) surrogate outcomes. Outcomes within the category a) and b) will be considered critically important to patients, and outcomes within the category c) will be regarded as important. We will use descriptive statistics to assess the proportion of studies that report each category of outcomes. We will perform univariable and multivariable analysis to explore associations between trial characteristics and the likelihood of reporting PIOs. DISCUSSION: The findings from this meta-epidemiological study will help health care professionals and researchers understand if the current covid-19 trials are effectively assessing and reporting the outcomes that are important to patients. If a deficiency in capturing PIOs is identified, this information may help inform the development of future RCTs in covid-19. SYSTEMATIC REVIEW REGISTRATIONS: Open Science Framework registration: osf.io/6xgjz .


Subject(s)
COVID-19 , Epidemiologic Studies , Humans , Patient Reported Outcome Measures , Randomized Controlled Trials as Topic , SARS-CoV-2 , Systematic Reviews as Topic
2.
Sci Rep ; 11(1): 17279, 2021 08 26.
Article in English | MEDLINE | ID: mdl-34446741

ABSTRACT

The Brazilian buffy-tufted-ear marmoset (Callithrix aurita), one of the world's most endangered primates, is threatened by anthropogenic hybridization with exotic, invasive marmoset species. As there are few genetic data available for C. aurita, we developed a PCR-free protocol with minimal technical requirements to rapidly generate genomic data with genomic skimming and portable nanopore sequencing. With this direct DNA sequencing approach, we successfully determined the complete mitogenome of a marmoset that we initially identified as C. aurita. The obtained nanopore-assembled sequence was highly concordant with a Sanger sequenced version of the same mitogenome. Phylogenetic analyses unexpectedly revealed that our specimen was a cryptic hybrid, with a C. aurita phenotype and C. penicillata mitogenome lineage. We also used publicly available mitogenome data to determine diversity estimates for C. aurita and three other marmoset species. Mitogenomics holds great potential to address deficiencies in genomic data for endangered, non-model species such as C. aurita. However, we discuss why mitogenomic approaches should be used in conjunction with other data for marmoset species identification. Finally, we discuss the utility and implications of our results and genomic skimming/nanopore approach for conservation and evolutionary studies of C. aurita and other marmosets.


Subject(s)
Callithrix/genetics , Endangered Species , Genomics/methods , Hybridization, Genetic/genetics , Nanopore Sequencing/methods , Animals , Brazil , Callithrix/classification , DNA, Mitochondrial/classification , DNA, Mitochondrial/genetics , Evolution, Molecular , Genome, Mitochondrial/genetics , Male , Phenotype , Phylogeny , Species Specificity
3.
BMC Genomics ; 22(1): 239, 2021 Apr 06.
Article in English | MEDLINE | ID: mdl-33823806

ABSTRACT

BACKGROUND: Callithrix marmosets are a relatively young primate radiation, whose phylogeny is not yet fully resolved. These primates are naturally para- and allopatric, but three species with highly invasive potential have been introduced into the southeastern Brazilian Atlantic Forest by the pet trade. There, these species hybridize with each other and endangered, native congeners. We aimed here to reconstruct a robust Callithrix phylogeny and divergence time estimates, and identify the biogeographic origins of autochthonous and allochthonous Callithrix mitogenome lineages. We sequenced 49 mitogenomes from four species (C. aurita, C. geoffroyi, C. jacchus, C. penicillata) and anthropogenic hybrids (C. aurita x Callithrix sp., C. penicillata x C. jacchus, Callithrix sp. x Callithrix sp., C. penicillata x C. geoffroyi) via Sanger and whole genome sequencing. We combined these data with previously published Callithrix mitogenomes to analyze five Callithrix species in total. RESULTS: We report the complete sequence and organization of the C. aurita mitogenome. Phylogenetic analyses showed that C. aurita was the first to diverge within Callithrix 3.54 million years ago (Ma), while C. jacchus and C. penicillata lineages diverged most recently 0.5 Ma as sister clades. MtDNA clades of C. aurita, C. geoffroyi, and C. penicillata show intraspecific geographic structure, but C. penicillata clades appear polyphyletic. Hybrids, which were identified by phenotype, possessed mainly C. penicillata or C. jacchus mtDNA haplotypes. The biogeographic origins of mtDNA haplotypes from hybrid and allochthonous Callithrix were broadly distributed across natural Callithrix ranges. Our phylogenetic results also evidence introgression of C. jacchus mtDNA into C. aurita. CONCLUSION: Our robust Callithrix mitogenome phylogeny shows C. aurita lineages as basal and C. jacchus lineages among the most recent within Callithrix. We provide the first evidence that parental mtDNA lineages of anthropogenic hybrid and allochthonous marmosets are broadly distributed inside and outside of the Atlantic Forest. We also show evidence of cryptic hybridization between allochthonous Callithrix and autochthonous C. aurita. Our results encouragingly show that further development of genomic resources will allow to more clearly elucidate Callithrix evolutionary relationships and understand the dynamics of Callithrix anthropogenic introductions into the Brazilian Atlantic Forest.


Subject(s)
Biological Evolution , Callithrix , Animals , Brazil , Callithrix/genetics , DNA, Mitochondrial/genetics , Humans , Phylogeny
4.
J Clin Epidemiol ; 115: 1-13, 2019 11.
Article in English | MEDLINE | ID: mdl-31055177

ABSTRACT

OBJECTIVES: The aim of the study was to develop a Grading of Recommendations, Assessment, Development and Evaluation (GRADE) summary of findings (SoF) table format that displays the critical information from a network meta-analysis (NMA). STUDY DESIGN AND SETTING: We applied a user experience model for data analysis based on four rounds of semistructured interviews. RESULTS: We interviewed 32 stakeholders who conduct or use MA. Four rounds of interviews produced six candidate NMA-SoF tables. Users found a final NMA-SoF table that included the following components highly acceptable: (1) details of the clinical question (PICO), (2) a plot depicting network geometry, (3) relative and absolute effect estimates, (4) certainty of evidence, (5) ranking of treatments, and (6) interpretation of findings. CONCLUSION: Using stakeholder feedback, we developed a new GRADE NMA-SoF table that includes the relevant components that facilitate understanding NMA findings and health decision-making.


Subject(s)
Information Dissemination/methods , Network Meta-Analysis , Abstracting and Indexing/methods , Decision Making , Evidence-Based Medicine , Humans , Research Report/standards
5.
Mol Ecol ; 27(22): 4397-4416, 2018 11.
Article in English | MEDLINE | ID: mdl-30252986

ABSTRACT

Understanding the molecular basis of repeatedly evolved phenotypes can yield key insights into the evolutionary process. Quantifying gene flow between populations is especially important in interpreting mechanisms of repeated phenotypic evolution, and genomic analyses have revealed that admixture occurs more frequently between diverging lineages than previously thought. In this study, we resequenced 47 whole genomes of the Mexican tetra from three cave populations, two surface populations and outgroup samples. We confirmed that cave populations are polyphyletic and two Astyanax mexicanus lineages are present in our data set. The two lineages likely diverged much more recently than previous mitochondrial estimates of 5-7 mya. Divergence of cave populations from their phylogenetically closest surface population likely occurred between ~161 and 191 k generations ago. The favoured demographic model for most population pairs accounts for divergence with secondary contact and heterogeneous gene flow across the genome, and we rigorously identified gene flow among all lineages sampled. Therefore, the evolution of cave-related traits occurred more rapidly than previously thought, and trogolomorphic traits are maintained despite gene flow with surface populations. The recency of these estimated divergence events suggests that selection may drive the evolution of cave-derived traits, as opposed to disuse and drift. Finally, we show that a key trogolomorphic phenotype QTL is enriched for genomic regions with low divergence between caves, suggesting that regions important for cave phenotypes may be transferred between caves via gene flow. Our study shows that gene flow must be considered in studies of independent, repeated trait evolution.


Subject(s)
Biological Evolution , Caves , Characidae/genetics , Gene Flow , Genetics, Population , Animals , Mexico , Models, Genetic , Phenotype , Phylogeny , Quantitative Trait Loci
7.
J Clin Epidemiol ; 93: 36-44, 2018 01.
Article in English | MEDLINE | ID: mdl-29051107

ABSTRACT

This article describes conceptual advances of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group guidance to evaluate the certainty of evidence (confidence in evidence, quality of evidence) from network meta-analysis (NMA). Application of the original GRADE guidance, published in 2014, in a number of NMAs has resulted in advances that strengthen its conceptual basis and make the process more efficient. This guidance will be useful for systematic review authors who aim to assess the certainty of all pairwise comparisons from an NMA and who are familiar with the basic concepts of NMA and the traditional GRADE approach for pairwise meta-analysis. Two principles of the original GRADE NMA guidance are that we need to rate the certainty of the evidence for each pairwise comparison within a network separately and that in doing so we need to consider both the direct and indirect evidence. We present, discuss, and illustrate four conceptual advances: (1) consideration of imprecision is not necessary when rating the direct and indirect estimates to inform the rating of NMA estimates, (2) there is no need to rate the indirect evidence when the certainty of the direct evidence is high and the contribution of the direct evidence to the network estimate is at least as great as that of the indirect evidence, (3) we should not trust a statistical test of global incoherence of the network to assess incoherence at the pairwise comparison level, and (4) in the presence of incoherence between direct and indirect evidence, the certainty of the evidence of each estimate can help decide which estimate to believe.


Subject(s)
GRADE Approach/trends , Network Meta-Analysis , Humans , Models, Theoretical , Systematic Reviews as Topic
8.
J Pediatr ; 181: 102-111.e5, 2017 02.
Article in English | MEDLINE | ID: mdl-27855998

ABSTRACT

OBJECTIVE: To determine safety and pharmacodynamics/efficacy of teduglutide in children with intestinal failure associated with short bowel syndrome (SBS-IF). STUDY DESIGN: This 12-week, open-label study enrolled patients aged 1-17 years with SBS-IF who required parenteral nutrition (PN) and showed minimal or no advance in enteral nutrition (EN) feeds. Patients enrolled sequentially into 3 teduglutide cohorts (0.0125 mg/kg/d [n = 8], 0.025 mg/kg/d [n = 14], 0.05 mg/kg/d [n = 15]) or received standard of care (SOC, n = 5). Descriptive summary statistics were used. RESULTS: All patients experienced ≥1 treatment-emergent adverse event; most were mild or moderate. No serious teduglutide-related treatment-emergent adverse events occurred. Between baseline and week 12, prescribed PN volume and calories (kcal/kg/d) changed by a median of -41% and -45%, respectively, with 0.025 mg/kg/d teduglutide and by -25% and -52% with 0.05 mg/kg/d teduglutide. In contrast, PN volume and calories changed by 0% and -6%, respectively, with 0.0125 mg/kg/d teduglutide and by 0% and -1% with SOC. Per patient diary data, EN volume increased by a median of 22%, 32%, and 40% in the 0.0125, 0.025, and 0.05 mg/kg/d cohorts, respectively, and by 11% with SOC. Four patients achieved independence from PN, 3 in the 0.05 mg/kg/d cohort and 1 in the 0.025 mg/kg/d cohort. Study limitations included its short-term, open-label design, and small sample size. CONCLUSIONS: Teduglutide was well tolerated in pediatric patients with SBS-IF. Teduglutide 0.025 or 0.05 mg/kg/d was associated with trends toward reductions in PN requirements and advancements in EN feeding in children with SBS-IF. TRIAL REGISTRATION: ClinicalTrials.gov:NCT01952080; EudraCT: 2013-004588-30.


Subject(s)
Enteral Nutrition/methods , Peptides/administration & dosage , Short Bowel Syndrome/drug therapy , Adolescent , Age Factors , Child , Child, Preschool , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Male , Patient Safety , Peptides/adverse effects , Prospective Studies , Risk Assessment , Severity of Illness Index , Sex Factors , Short Bowel Syndrome/diagnosis , Short Bowel Syndrome/therapy , Treatment Outcome
9.
PLoS Negl Trop Dis ; 9(12): e0004252, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26709695

ABSTRACT

Plasmodium vivax is the most prevalent malarial species in South America and exerts a substantial burden on the populations it affects. The control and eventual elimination of P. vivax are global health priorities. Genomic research contributes to this objective by improving our understanding of the biology of P. vivax and through the development of new genetic markers that can be used to monitor efforts to reduce malaria transmission. Here we analyze whole-genome data from eight field samples from a region in Cordóba, Colombia where malaria is endemic. We find considerable genetic diversity within this population, a result that contrasts with earlier studies suggesting that P. vivax had limited diversity in the Americas. We also identify a selective sweep around a substitution known to confer resistance to sulphadoxine-pyrimethamine (SP). This is the first observation of a selective sweep for SP resistance in this species. These results indicate that P. vivax has been exposed to SP pressure even when the drug is not in use as a first line treatment for patients afflicted by this parasite. We identify multiple non-synonymous substitutions in three other genes known to be involved with drug resistance in Plasmodium species. Finally, we found extensive microsatellite polymorphisms. Using this information we developed 18 polymorphic and easy to score microsatellite loci that can be used in epidemiological investigations in South America.


Subject(s)
Genetic Variation , Genome, Protozoan/genetics , Malaria, Vivax/parasitology , Microsatellite Repeats/genetics , Plasmodium vivax/genetics , Adolescent , Antimalarials/therapeutic use , Base Sequence , Child , Colombia/epidemiology , Drug Combinations , Drug Resistance , Female , Genome-Wide Association Study , Humans , Malaria, Vivax/drug therapy , Malaria, Vivax/epidemiology , Molecular Sequence Data , Plasmodium vivax/drug effects , Plasmodium vivax/isolation & purification , Pyrimethamine/therapeutic use , Sequence Analysis, DNA , Sulfadoxine/therapeutic use
12.
J Nat Prod ; 58(2): 201-8, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7769388

ABSTRACT

The cyanobacteria-containing Caribbean sponge, Calyx cf. podatypa, was collected from three sites in the Bahamas. In each of the three collections, a polar solvent partition fraction contained six known compounds including five diketopiperazines [1-4,6] and phenylacetic acid, along with a new diketopiperazine, cyclo-(4-methyl-R-proline-S-norvaline) [5]. Interestingly, all six diketopiperazines are proline-derived cyclic dipeptides. This is the first example for this class of peptide derivative to be isolated from a Calyx sponge. Parallel studies of one of the sponge collections in which the ectosome (cyanobacteria-rich) was separated from the endosome (no cyanobacteria) revealed no significant differences in their content of diketopiperazines.


Subject(s)
Piperazines/chemistry , Porifera/chemistry , Amino Acid Sequence , Animals , Bahamas , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Optical Rotation , Piperazines/isolation & purification
13.
J Pediatr ; 122(5 Pt 1): 693-6, 1993 May.
Article in English | MEDLINE | ID: mdl-8496744

ABSTRACT

To test the hypothesis that the presence of osteopenia in juvenile rheumatoid arthritis is directly correlated with clinical disease activity and therefore reversible, we prospectively studied cortical bone mineral density (BMD) serially in 27 children. Twenty-four (89%) had BMD > or = 2 SD below age-related normal values (disease duration 49.3 +/- 7.7 months) at the beginning of the study. Of 27 children who had clinical disease improvement measured by a disease activity score during our study period, 17 (63%) had significant improvement or significant normalization, or both, of their BMD (0.34 +/- 0.13 gm/cm2 at initiation and 0.41 +/- 0.17 gm/cm2 at completion, p < 0.05; disease activity score of 3.4 +/- 0.2 at initiation and 1.4 +/- 0.2 at completion, p < 0.005). The increase in BMD was associated with a similar directional change in serum osteocalcin concentrations (4.6 +/- 1 ng/ml at initiation vs 9.1 +/- 1.1 ng/ml). The 10 patients whose disease became or remained active had a decreased or unchanged low serum osteocalcin level and BMD (BMD 0.37 +/- 0.17 gm/cm2 at initiation and 0.37 +/- 0.16 gm/cm2 at completion; disease activity score of 3.1 +/- 0.3 at initiation and 3.4 +/- 0.2 at study completion). We conclude that children with JRA who have improvement in their disease activity have an improvement in BMD heralded by an increase in serum osteocalcin values.


Subject(s)
Arthritis, Juvenile/physiopathology , Bone Density , Bone Diseases, Metabolic/physiopathology , Adolescent , Arthritis, Juvenile/blood , Arthritis, Juvenile/complications , Bone Diseases, Metabolic/etiology , Child , Child, Preschool , Female , Humans , Male , Osteocalcin/blood , Prospective Studies
16.
J Pediatr ; 116(4): 574-80, 1990 Apr.
Article in English | MEDLINE | ID: mdl-2319404

ABSTRACT

We studied bone mineral metabolism prospectively in 113 children with chronic rheumatic diseases (juvenile arthritis, systemic lupus erythematosus, and juvenile dermatomyositis) to determine the relationship of serum levels of osteocalcin to rheumatic disease activity and corticosteroid usage, and to determine, in part, the cause of osteopenia in this population. Disease activity was quantitated by historical, clinical, and serologic means and an activity score derived. The 113 children were divided according to the expression of their disease, which was active (group 1: mean score 3.42, mean erythrocyte sedimentation rate 28 mm/hr) or inactive (group 2: score 1.7, erythrocyte sedimentation rate 15 mm/hr) (p less than 0.02 group 1 vs group 2 for each value), or which remitted during the study (group 3). We found that serum levels of osteocalcin, but not those of ionized calcium, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and parathyroid hormone, were reduced in group 1 children even before corticosteroid therapy was employed. Children in both group 2 and group 3 had normal osteocalcin levels despite the use of corticosteroids. The reduced levels of osteocalcin were predictive of a reduction in bone mass measured by photon absorptiometry in 16 of 19 children so studied. We conclude that skeletal abnormalities that result in a reduced bone mass occur in the clinical course of the majority of children with active chronic rheumatic diseases, are associated with reduced osteocalcin levels, and are not related to the use of corticosteroids. Serum osteocalcin levels may be a sensitive marker for reduced osteoblast activity and bone formation in children with chronic rheumatic diseases.


Subject(s)
Arthritis, Juvenile/blood , Dermatomyositis/blood , Lupus Erythematosus, Systemic/blood , Osteocalcin/blood , Adolescent , Adult , Arthritis, Juvenile/metabolism , Bone Density , Bone Diseases, Metabolic/blood , Bone Diseases, Metabolic/etiology , Calcium/blood , Child , Child, Preschool , Chronic Disease , Dermatomyositis/metabolism , Female , Humans , Hydroxycholecalciferols/blood , Infant , Lupus Erythematosus, Systemic/metabolism , Male , Prospective Studies
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