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1.
J Exp Biol ; 226(3)2023 02 01.
Article in English | MEDLINE | ID: mdl-36651231

ABSTRACT

As the climate continues to change, it is not just the magnitude of these changes that is important - equally critical is the timing of these events. Conditions that may be well tolerated at one time can become detrimental if experienced at another, as a result of seasonal acclimation. Temperature is the most critical variable as it affects most aspects of an organism's physiology. To address this, we quantified arm regeneration and respiration in the Australian brittle star Ophionereis schayeri for 10 weeks in response to a +3°C warming (18.5°C, simulating a winter heatwave) compared with ambient winter temperature (15.5°C). The metabolic scaling rate (b=0.635 at 15.5°C and 0.746 at 18.5°C) with respect to size was similar to that of other echinoderms and was not affected by temperature. Elevated temperature resulted in up to a 3-fold increase in respiration and a doubling of regeneration growth; however, mortality was greater (up to 44.2% at 18.5°C), especially in the regenerating brittle stars. Metabolic rate of the brittle stars held at 18.5°C was much higher than expected (Q10≈23) and similar to that of O. schayeri tested in summer, which was near their estimated thermotolerance limits. The additional costs associated with the elevated metabolism and regeneration rates incurred by the unseasonably warm winter temperatures may lead to increased mortality and predation risk.


Subject(s)
Arm , Echinodermata , Animals , Seasons , Australia , Echinodermata/physiology , Temperature , Acclimatization/physiology , Oceans and Seas
2.
Adv Mar Biol ; 87(1): 443-472, 2020.
Article in English | MEDLINE | ID: mdl-33293019

ABSTRACT

The invasive brittle star Ophiothela mirabilis (family Ophiotrichidae), a tropical Indo-Pacific endemic species, first reported in Atlantic waters off southern Brazil in 2000, has extended its range northward to the Caribbean Sea, to the Lesser Antilles in 2011, and was first reported in south Florida in January 2019. Its occurrence in southeast Florida extends along nearly 70km of coastline, from near the Port of Miami, Miami-Dade County, northward to Deerfield Beach, Broward County. It occurs abundantly as an epizoite on octocorals, attaining population densities of 25 individuals and more per 10-cm long octocoral stem. The surface texture of octocoral hosts (rough, smooth) did not affect the densities of the ophiuroid epizoites, and there were significantly greater abundances on octocorals during two winter sampling periods than in the summer. Beige and orange-coloured morphs are sometimes present on the same octocoral stem. Gut content analysis supported a suspension feeding mode, revealing essentially identical ingested items in both colour morphs with a preponderance of amorphous detritus and filamentous algae. Molecular genetic evidence (COI & 16s) has established the identity of O. mirabilis and its relationship to invasive Brazilian populations. The orange and beige morphs form two distinct, but closely related lineages that may represent two separate introductions. The orange morph shares haplotypes with Brazilian and Caribbean specimens suggesting a further range expansion of the 'original' invasion. The beige morph, however, shares haplotypes with specimens from the Mexican Pacific and Peru and potentially represents a secondary introduction. Traits promoting dispersal and establishment of this species in new habitats are manifold: vagility and ability to cling tightly to diverse host taxa (e.g. sponges, cnidarians, bryozoans, and echinoderms), frequent asexual reproduction (fissiparity), suspension feeding, including a wide range of dietary items, possession of integument-covered ossicles and arm spines offering protection from predators, and an effective competitive edge over associated microbiota for substrate space.


Subject(s)
Echinodermata , Introduced Species , Animals , Ecosystem , Florida
3.
PLoS One ; 14(1): e0210331, 2019.
Article in English | MEDLINE | ID: mdl-30673722

ABSTRACT

We re-describe and confirm the validity of Ophiothrix trindadensis Tommasi, 1970 (Echinodermata: Ophiuroidea). This is a native species from Brazil, however it lacked a type series deposited in scientific collections. The recognition of O. trindadensis was made possible using integrative taxonomy applied to many specimens from the type locality (Trindade Island) as well as from different locations along the Brazilian coast (Araçá Bay and Estuarine Complex of Paranaguá). Initially, 835 specimens were studied and divided into four candidate species (CS) inferred from external morphological characters. Afterwards, the CSs were compared using integrative taxonomy based on external morphology, arm microstructures morphology (arm ossicle), morphometry, and molecular studies (fragments of the mitochondrial genes 16S and COI). Analyses indicated CS1 and CS2 as O. trindadensis, and CS3 as O. angulata, both valid species. CS4 remains O. cf. angulata as more data, including their ecology and physiology, are needed to be definitively clarified. Our integrative investigation using specimens from the type locality overcame the lack of type specimens and increased the reliable identification of O. trindadensis and O. angulata.


Subject(s)
Echinodermata/classification , Animals , Bayes Theorem , Brazil , DNA, Mitochondrial/genetics , Echinodermata/anatomy & histology , Echinodermata/genetics , Electron Transport Complex IV/genetics , Genes, Mitochondrial , Genetic Variation , Phylogeny , Species Specificity
4.
Zootaxa ; 4405(1): 1-66, 2018 Apr 05.
Article in English | MEDLINE | ID: mdl-29690229

ABSTRACT

The detailed study of arm ossicles, particularly the lateral arm plates, is providing valuable information in the elucidation of ophiuroid taxonomy. The present study describes in detail 16 species of brittle stars from Araçá Bay, Brazil. This information is used to construct the first interactive electronic key, providing a valuable resource for a broad range of researchers. Brittle stars families were divided into three groups based on their spatial distribution: i) infaunal species of intertidal and shallow subtidal belonging to Amphiuridae and Ophiactidae, ii) epizoic species belonging to Amphiuridae, Ophiactidae, and Ophiotrichidae and, iii) epifaunal species of the subtidal belonging to Ophiodermatidae and Hemieuryalidae. In the global context of recent revisions of ophiuroid taxonomy, the present work provides additional characters for use in future phylogenetic studies.


Subject(s)
Echinodermata , Animals , Bays , Brazil , Phylogeny , Water
6.
J Emerg Med ; 52(2): 169-175, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27789114

ABSTRACT

BACKGROUND: Pediatric adnexal torsion is rare, can be challenging to recognize, and may result in ovarian loss. OBJECTIVE: We sought to identify and compare the defining characteristics of adnexal torsion in premenarchal and postmenarchal girls. METHODS: A retrospective cohort study was performed at a tertiary care children's hospital, including patients diagnosed postnatally with adnexal (ovarian or tubal) torsion between 1997 and 2013. Proportions were compared using relative risk regression. RESULTS: Adnexal torsion was found in 59 premenarchal and 43 postmenarchal girls. Abdominal pain was the most common chief complaint (54%). History included reports of pain (96%), vomiting (67%), and fever (19%). Excluding 12 patients with isolated tubal torsion and 19 with a teratoma, there were no statistically significant differences in ovarian loss in premenarchal vs. postmenarchal girls (47% and 25% respectively; relative risk [RR] = 1.8 [95% confidence interval {CI} 0.9-3.8]), left- vs. right-sided torsion (47% and 32%; RR = 1.5 [95% CI 0.8-2.7]), pain duration ≤ 2 days vs. > 2 days (31% and 41%; RR = 0.8 [95% CI 0.4-1.5]; n = 64) and severe pain vs. mild to moderate (38% and 33%; RR = 1.1 [95% CI 0.7-1.5]; n = 56). CONCLUSIONS: The diagnosis of pediatric adnexal torsion is difficult and often delayed. Pain and tenderness may not be isolated to a unilateral lower quadrant. Although traditionally considered a postmenarchal problem, in a pediatric academic emergency department adnexal torsion occurred with similar frequency in premenarchal and postmenarchal girls. The potential for organ salvage means that adnexal torsion should be considered in all females presenting with acute abdominal pain regardless of age or menstrual history.


Subject(s)
Adnexal Diseases/surgery , Torsion Abnormality/surgery , Abdominal Pain/etiology , Adnexal Diseases/epidemiology , Adolescent , Child , Child, Preschool , Cohort Studies , Female , Hospitals, Pediatric/organization & administration , Humans , Laparoscopy/methods , Laparoscopy/statistics & numerical data , Menarche/physiology , Necrosis/mortality , Retrospective Studies , Teratoma/epidemiology , Torsion Abnormality/epidemiology
7.
J Health Care Poor Underserved ; 27(3): 1080-96, 2016.
Article in English | MEDLINE | ID: mdl-27524753

ABSTRACT

American Indian/Alaska Native (AI/AN) children have a high risk for poor health outcomes. Race/ethnicity and functional impairments are linked with health care disparities. While data exist for other race/ethnicity groups, little is known about outcomes for AI/AN children with functional impairments. In this study the Functional Independence Measure for Children (WeeFIM®) was used to determine differences in outcomes between AI/AN and White children receiving inpatient rehabilitation for functional impairments at one pediatric rehabilitation facility. American Indian/Alaska Native and White children had similar impairment types and functional levels at admission to inpatient rehabilitation. Both groups experienced functional improvement during rehabilitation. At discharge, AI/AN children had lower total functional scores and had less improvement in mobility scores compared with White children, with more impairment in physical mobility at discharge. This is one of the first studies to show a disparity in functional outcomes for AI/AN children compared with White children during inpatient rehabilitation.


Subject(s)
Healthcare Disparities , Inpatients , Rehabilitation , Child , Humans , Indians, North American , Recovery of Function , White People
8.
PM R ; 8(6): 529-35, 2016 06.
Article in English | MEDLINE | ID: mdl-26514788

ABSTRACT

BACKGROUND: Functional impairments from central nervous system (CNS) dysfunction experienced by pediatric patients with cancer diagnoses are well documented. However, little is known of these patients' functional outcomes and potential complications while receiving inpatient rehabilitation services. OBJECTIVE: To compare functional outcomes and unplanned transfer rates of pediatric patients with impairments associated with CNS dysfunction between those with primary cancer diagnoses and noncancer diagnoses while receiving inpatient rehabilitation care. DESIGN: Retrospective comparison cohort study. SETTING: Inpatient rehabilitation unit within a regional tertiary care pediatric hospital. PARTICIPANTS: Patients with CNS-based functional impairments with primary cancer diagnoses (n = 107) and noncancer diagnoses (n = 480), admitted to the inpatient rehabilitation unit between January 1, 2005 and April 1, 2012, who were aged 1 to 20 years at time of admission. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Pediatric Functional Independence Measure (WeeFIM) reflecting functional status was collected at admission and discharge with change score and WeeFIM efficiency calculated. Length of stay on the rehabilitation unit and unplanned transfer rates were also collected. RESULTS: No significant difference in total WeeFIM scores at admission was found between cancer and noncancer groups. Both groups had significant increases in WeeFIM scores at discharge (P < .001). The noncancer group had significantly higher WeeFIM change in self-care (P = .001), mobility (P = .009), and total score (P = .004) and had a greater length of stay (P < .001). A comparison of WeeFIM efficiency in all domains revealed no significant difference between cancer and noncancer groups. There was also no significant between-group difference in unplanned transfer rates. CONCLUSIONS: Children with CNS-based functional impairments with cancer and noncancer diagnoses made functional gains with similar WeeFIM efficiencies after undergoing inpatient rehabilitation. However, patients with noncancer diagnoses made greater gains in self care, mobility, and total scores with longer stays on the rehabilitation service. No significant difference was found in unplanned transfer rates between cancer and noncancer groups for acute medical care.


Subject(s)
Neoplasms/rehabilitation , Child , Humans , Inpatients , Length of Stay , Retrospective Studies , Self Care
9.
PeerJ ; 3: e1188, 2015.
Article in English | MEDLINE | ID: mdl-26413431

ABSTRACT

Sharks and rays are increasingly being identified as high-risk species for extinction, prompting urgent assessments of their local or regional populations. Advanced genetic analyses can contribute relevant information on effective population size and connectivity among populations although acquiring sufficient regional sample sizes can be challenging. DNA is typically amplified from tissue samples which are collected by hand spears with modified biopsy punch tips. This technique is not always popular due mainly to a perception that invasive sampling might harm the rays, change their behaviour, or have a negative impact on tourism. To explore alternative methods, we evaluated the yields and PCR success of DNA template prepared from the manta ray mucus collected underwater and captured and stored on a Whatman FTA™ Elute card. The pilot study demonstrated that mucus can be effectively collected underwater using toothbrush. DNA stored on cards was found to be reliable for PCR-based population genetics studies. We successfully amplified mtDNA ND5, nuclear DNA RAG1, and microsatellite loci for all samples and confirmed sequences and genotypes being those of target species. As the yields of DNA with the tested method were low, further improvements are desirable for assays that may require larger amounts of DNA, such as population genomic studies using emerging next-gen sequencing.

10.
PLoS One ; 10(8): e0129668, 2015.
Article in English | MEDLINE | ID: mdl-26247465

ABSTRACT

BACKGROUND: Recent genomic information has revealed that neuroglobin and cytoglobin are the two principal lineages of vertebrate hemoglobins, with the latter encompassing the familiar myoglobin and α-globin/ß-globin tetramer hemoglobin, and several minor groups. In contrast, very little is known about hemoglobins in echinoderms, a phylum of exclusively marine organisms closely related to vertebrates, beyond the presence of coelomic hemoglobins in sea cucumbers and brittle stars. We identified about 50 hemoglobins in sea urchin, starfish and sea cucumber genomes and transcriptomes, and used Bayesian inference to carry out a molecular phylogenetic analysis of their relationship to vertebrate sequences, specifically, to assess the hypothesis that the neuroglobin and cytoglobin lineages are also present in echinoderms. RESULTS: The genome of the sea urchin Strongylocentrotus purpuratus encodes several hemoglobins, including a unique chimeric 14-domain globin, 2 androglobin isoforms and a unique single androglobin domain protein. Other strongylocentrotid genomes appear to have similar repertoires of globin genes. We carried out molecular phylogenetic analyses of 52 hemoglobins identified in sea urchin, brittle star and sea cucumber genomes and transcriptomes, using different multiple sequence alignment methods coupled with Bayesian and maximum likelihood approaches. The results demonstrate that there are two major globin lineages in echinoderms, which are related to the vertebrate neuroglobin and cytoglobin lineages. Furthermore, the brittle star and sea cucumber coelomic hemoglobins appear to have evolved independently from the cytoglobin lineage, similar to the evolution of erythroid oxygen binding globins in cyclostomes and vertebrates. CONCLUSION: The presence of echinoderm globins related to the vertebrate neuroglobin and cytoglobin lineages suggests that the split between neuroglobins and cytoglobins occurred in the deuterostome ancestor shared by echinoderms and vertebrates.


Subject(s)
Echinodermata/genetics , Globins/genetics , Nerve Tissue Proteins/genetics , Animals , Bayes Theorem , Cytoglobin , Echinodermata/chemistry , Globins/chemistry , Likelihood Functions , Models, Molecular , Nerve Tissue Proteins/chemistry , Neuroglobin , Phylogeny , Protein Conformation
11.
Resuscitation ; 85(8): 1099-105, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24830871

ABSTRACT

AIM: Studies demonstrating the impact of resuscitation simulation curricula on performance are limited. Our objective was to create and evaluate a simulation-based resuscitation curriculum's impact on pediatric residents' performance in a simulated resuscitation. METHODS: We developed a standardized simulation-based pediatric resident resuscitation curriculum consisting of nine modules, incorporating four domains (basic skills, airway/breathing, circulation and team management) and specific topics (e.g., anaphylaxis). Each module was presented four times over the academic year. Evaluation of the curriculum consisted of pre- and post-intervention video-recorded performances of a simulated pediatric resuscitation by 10 resident resuscitation teams, scored using the Simulation Team Assessment Tool (STAT). The effectiveness of the standardized curriculum on medical (basics, airway/breathing, circulation) and team management, and on knowledge test scores was evaluated by comparing pre- and post-intervention STAT scores using unpaired two-sided T-test. The impact of group curriculum participation on team performance (STAT scores) was analyzed using linear regression. RESULTS: Overall team performance STAT scores increased post-intervention (mean pre-test 0.61, post-test 0.74, p<0.001), as did management of the basics of resuscitation, airway/breathing and teamwork (mean basics: pre 0.46, post 0.62, p=0.001; mean airway/breathing: pre 0.63, post 0.76, p=0.01; mean teamwork: pre 0.61, post 0.79, p=0.003). Regression analysis provided evidence for a training "dose-response" among the post-intervention teams, with teams exposed to more training achieving higher performance scores (p=0.004). CONCLUSIONS: We created a standardized simulation-based pediatric resuscitation curriculum that increased pediatric residents' scores on medical management and teamwork skills in a dose dependent relationship.


Subject(s)
Clinical Competence/standards , Computer Simulation , Curriculum/standards , Education, Medical, Continuing/methods , Internship and Residency/methods , Pediatrics/education , Resuscitation/education , Educational Measurement , Humans
12.
J Pediatr ; 164(5): 1181-1188.e8, 2014 May.
Article in English | MEDLINE | ID: mdl-24607242

ABSTRACT

OBJECTIVE: To characterize the population pharmacokinetics (PK) of oral baclofen and assess impact of patient-specific covariates in children with cerebral palsy (CP) in order to support its clinical use. SUBJECTS DESIGN: Children (2-17 years of age) with CP received a dose of titrated oral baclofen from 2.5 mg 3 times a day to a maximum tolerated dose of up to 20 mg 4 times a day. PK sampling followed titration of 10-12 weeks. Serial R- and S-baclofen plasma concentrations were measured for up to 16 hours in 49 subjects. Population PK modeling was performed using NONMEM 7.1 (ICON PLC; Ellicott City, Maryland). RESULTS: R- and S-baclofen showed identical concentration-time profiles. Both baclofen enantiomers exhibited linear and dose/kg-proportional PK, and no sex differences were observed. Average baclofen terminal half-life was 4.5 hours. A 2-compartment PK model with linear elimination and transit absorption steps adequately described concentration-time profiles of both baclofen enantiomers. The mean population estimate of apparent clearance/F was 0.273 L/h/kg with 33.4% inter-individual variability (IIV), and the apparent volume of distribution (Vss/F) was 1.16 L/kg with 43.9% IIV. Delayed absorption was expressed by a mean transit time of 0.389 hours with 83.7% IIV. Body weight, a possible genetic factor, and age were determinants of apparent clearance in these children. CONCLUSION: The PK of oral baclofen exhibited dose-proportionality and were adequately described by a 2-compartment model. Our population PK findings suggest that baclofen dosage can be based on body weight (2 mg/kg per day) and the current baclofen dose escalation strategy is appropriate in the treatment of children with CP older than 2 years of age.


Subject(s)
Baclofen/pharmacokinetics , Cerebral Palsy/drug therapy , Muscle Relaxants, Central/pharmacokinetics , Absorption , Administration, Oral , Adolescent , Baclofen/blood , Baclofen/therapeutic use , Body Weight , Cerebral Palsy/blood , Child , Child, Preschool , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Half-Life , Humans , Male , Metabolic Clearance Rate , Models, Statistical , Multivariate Analysis , Muscle Relaxants, Central/blood , Muscle Relaxants, Central/therapeutic use
13.
Biol Bull ; 205(1): 54-65, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12917222

ABSTRACT

The burrowing brittle star Hemipholis elongata (Say) possesses hemoglobin-containing coelomocytes (RBCs) in its water vascular system. The RBCs, which circulate between the arms and body, are thought to play a role in oxygen transport. The hemoglobin of adult animals has a moderate affinity for oxygen (P(50) = 11.4 mm Hg at pH 8, 20 degrees C, measured in cellulo) and exhibits cooperativity (Hill coefficient > 1.7). The hemoglobin of juveniles has a higher affinity (P(50) = 2.3 mmHg at pH 8.0, 20 degrees C) and also exhibits cooperativity. The oxygen-binding properties of the hemoglobin are relatively insensitive to pH, temperature, and hydrogen sulfide. Adult hemoglobin is a heterogeneous mixture composed of three major fractions. The combined results of electrospray mass spectrometry and oxygen-binding experiments performed on purified fractions indicate that the native hemoglobin is in the form of homopolymers. A partial amino acid sequence (about 40 amino acids) of adult hemoglobin reveals little homology with holothurian hemoglobins.


Subject(s)
Echinodermata/physiology , Hemoglobins/metabolism , Hemoglobins/physiology , Oxygen/metabolism , Amino Acid Sequence , Animals , Kinetics , Mass Spectrometry , Molecular Sequence Data , Protein Binding/physiology , South Carolina
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