Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 96
Filter
1.
iScience ; 26(10): 108027, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37860763

ABSTRACT

Invasive freshwater mussels, such as the zebra (Dreissena polymorpha), quagga (Dreissena rostriformis bugensis), and golden (Limnoperna fortunei) mussel have spread outside their native ranges throughout many regions of the North American, South American, and European continents in recent decades, damaging infrastructure and the environment. This review describes ongoing efforts by multiple groups to develop genetic biocontrol methods for invasive mussels. First, we provide an overview of genetic biocontrol strategies that have been applied in other invasive or pest species. Next, we summarize physical and chemical methods that are currently in use for invasive mussel control. We then describe the multidisciplinary approaches our groups are employing to develop genetic biocontrol tools for invasive mussels. Finally, we discuss the challenges and limitations of applying genetic biocontrol tools to invasive mussels. Collectively, we aim to openly share information and combine expertise to develop practical tools to enable the management of invasive freshwater mussels.

2.
J Environ Manage ; 332: 117383, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36736086

ABSTRACT

Freshwater invasive species, such as the quagga mussel (Dreissena rostriformis bugensis), are causing over $1 billion USD annually in damages to water infrastructure, recreation, and the environment. Once established, quagga and other dreissenid mussels are extremely difficult to eradicate. Preventing the spread of these invasives is critical and of high management concern. Invasive dreissenid establishment is predicated upon both successful dispersal from a source and suitable habitat in the uninfested waterbody to which they are transported. Recreational boaters have become predominant dispersal vectors making it possible to forecast the risk of invasion of waterbodies for more targeted management and prevention. We developed an integrated mussel dispersal model that couples a constrained gravity model and habitat suitability model to forecast future invasions. The model simulates boater movement between lakes, the likelihood of boats transporting mussels, and the likelihood that those mussels survive in the environmental conditions of the new lake. Model output was most sensitive to changes in boater threshold, then buffer zones, while not as sensitive to changes in habitat suitability. From an initial infested source pool of 11 among 402 Western inland US lakes, we forecast additional lakes infested in several possible simulation scenarios. Constraining movement reduced connectivity between waterbodies with amplifying effects at different distance levels. This model can be used to determine waterbodies most at risk for dreissenid mussel invasion and to highlight the importance of multifactor integrated models in environmental management.


Subject(s)
Bivalvia , Dreissena , Animals , Lakes , Ecosystem , Water/chemistry
3.
Diabetes Metab ; 46(2): 110-118, 2020 04.
Article in English | MEDLINE | ID: mdl-30366067

ABSTRACT

AIM: Older people with type 2 diabetes (T2DM) are at an increased risk of hypoglycaemia and its consequences. However, efficacy and safety data for basal insulin therapy are limited in these individuals. This patient-level meta-analysis assessed the treatment effects of insulin glargine 300 U/mL (Gla-300) versus glargine 100 U/mL (Gla-100) in people with T2DM ≥ 65 years old. METHODS: Data were pooled for patients randomised to receive Gla-300 or Gla-100 in the Phase 3a, treat-to-target EDITION 1, 2 and 3 trials. Glycaemic efficacy, hypoglycaemia, changes in body weight and insulin dosage and adverse events were examined over 6 months' treatment with Gla-300 versus Gla-100 for participants aged ≥ 65 and < 65 years. RESULTS: Of 2496 participants randomised, 662 were ≥ 65 years (Gla-300, n = 329; Gla-100, n = 333). Glycaemic control was comparable for Gla-300 and Gla-100 in participants ≥ 65 years (LS mean [95% CI] difference in HbA1c change from baseline to month 6: 0.00 [-0.14 to 0.15] %; 0.00 [-1.53 to 1.64] mmol/mol) and < 65 years (0.00 [-0.09 to 0.08] %; 0.00 [-0.98 to 0.87] mmol/mol). Fewer participants receiving Gla-300 versus Gla-100 experienced nocturnal confirmed (≤ 3.9 mmol/L [≤ 70 mg/dL]) or severe hypoglycaemia (relative risk: ≥ 65 years: 0.70 [0.57 to 0.85]; < 65 years: 0.77 [0.68 to 0.87]). Annualised rates of nocturnal confirmed or severe hypoglycaemia were lower with Gla-300 than Gla-100 for both age groups. CONCLUSION: Gla-300 was associated with a reduced risk of nocturnal hypoglycaemia versus Gla-100, accompanied by comparable glycaemic improvement, for people aged ≥ 65 and < 65 years with T2DM.


Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemia/chemically induced , Hypoglycemic Agents/therapeutic use , Insulin Glargine/therapeutic use , Adult , Age Factors , Aged , Aged, 80 and over , Diabetes Mellitus, Type 2/blood , Dose-Response Relationship, Drug , Female , Glycated Hemoglobin/analysis , Glycemic Control , Humans , Hypoglycemia/blood , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Insulin Glargine/administration & dosage , Insulin Glargine/adverse effects , Male , Middle Aged
4.
Evodevo ; 10: 33, 2019.
Article in English | MEDLINE | ID: mdl-31867094

ABSTRACT

BACKGROUND: Phoronids, rhynchonelliform and linguliform brachiopods show striking similarities in their embryonic fate maps, in particular in their axis specification and regionalization. However, although brachiopod development has been studied in detail and demonstrated embryonic patterning as a causal factor of the gastrulation mode (protostomy vs deuterostomy), molecular descriptions are still missing in phoronids. To understand whether phoronids display underlying embryonic molecular mechanisms similar to those of brachiopods, here we report the expression patterns of anterior (otx, gsc, six3/6, nk2.1), posterior (cdx, bra) and endomesodermal (foxA, gata4/5/6, twist) markers during the development of the protostomic phoronid Phoronopsis harmeri. RESULTS: The transcription factors foxA, gata4/5/6 and cdx show conserved expression in patterning the development and regionalization of the phoronid embryonic gut, with foxA expressed in the presumptive foregut, gata4/5/6 demarcating the midgut and cdx confined to the hindgut. Furthermore, six3/6, usually a well-conserved anterior marker, shows a remarkably dynamic expression, demarcating not only the apical organ and the oral ectoderm, but also clusters of cells of the developing midgut and the anterior mesoderm, similar to what has been reported for brachiopods, bryozoans and some deuterostome Bilateria. Surprisingly, brachyury, a transcription factor often associated with gastrulation movements and mouth and hindgut development, seems not to be involved with these patterning events in phoronids. CONCLUSIONS: Our description and comparison of gene expression patterns with other studied Bilateria reveals that the timing of axis determination and cell fate distribution of the phoronid shows highest similarity to that of rhynchonelliform brachiopods, which is likely related to their shared protostomic mode of development. Despite these similarities, the phoronid Ph. harmeri also shows particularities in its development, which hint to divergences in the arrangement of gene regulatory networks responsible for germ layer formation and axis specification.

5.
Dev Biol ; 448(2): 119-135, 2019 04 15.
Article in English | MEDLINE | ID: mdl-30661645

ABSTRACT

In a multitude of organisms, transcription factors of the basic helix-loop-helix (bHLH) family control the expression of genes required for organ development and tissue differentiation. The functions of different bHLH transcription factors in the specification of nervous system and paraxial mesoderm have been widely investigated in various model systems. Conversely, the knowledge of the role of these regulators in the development of the axial mesoderm, the embryonic territory that gives rise to the notochord, and the identities of their target genes, remain still fragmentary. Here we investigated the transcriptional regulation and target genes of Bhlh-tun1, a bHLH transcription factor expressed in the developing Ciona notochord as well as in additional embryonic territories that contribute to the formation of both larval and adult structures. We describe its possible role in notochord formation, its relationship with the key notochord transcription factor Brachyury, and suggest molecular mechanisms through which Bhlh-tun1 controls the spatial and temporal expression of its effectors.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Ciona/embryology , Ciona/genetics , Gene Regulatory Networks , Notochord/metabolism , Animals , Base Sequence , Basic Helix-Loop-Helix Transcription Factors/genetics , Body Patterning/genetics , Embryo, Nonmammalian/metabolism , Enhancer Elements, Genetic/genetics , Fetal Proteins/genetics , Fetal Proteins/metabolism , Gene Expression Regulation, Developmental , Notochord/embryology , Reproducibility of Results , T-Box Domain Proteins/genetics , T-Box Domain Proteins/metabolism , Up-Regulation/genetics
7.
Diabetes Metab ; 45(4): 330-340, 2019 09.
Article in English | MEDLINE | ID: mdl-30496834

ABSTRACT

AIM: Second-generation basal insulin analogues (e.g. insulin degludec, insulin glargine 300 U/mL), were designed to further extend the duration of insulin action and reduce within-day and day-to-day variability, and consequently hypoglycaemia risk, versus earlier long-acting basal insulins. This review examines the pharmacokinetic/pharmacodynamic characteristics of insulin degludec (100, 200 U/mL) and insulin glargine (100, 300 U/mL), and their influence on clinical outcomes. METHODS: Available pharmacokinetic/pharmacodynamic publications comparing insulin degludec and insulin glargine were reviewed. RESULTS: Both insulin degludec and insulin glargine 300 U/mL have more prolonged and stable pharmacokinetic/pharmacodynamic profiles than the earlier basal insulin analogue, insulin glargine 100 U/mL. Insulin glargine 300 U/mL (0.4 U/kg, morning) showed a more stable pharmacodynamic profile (20% lower within-day variability [P = 0.047]) and more even 24-h distribution (over each 6-h quartile) than insulin degludec 100 U/mL, whereas the supratherapeutic 0.6 U/kg dose demonstrated a similar, albeit non-significant, trend. In contrast, a second clamp study indicated lower day-to-day variability in the 24-h glucose-lowering effect (variance ratio 3.70, P < 0.0001), and more even dosing over each 6-h quartile, with insulin degludec 200 U/mL versus insulin glargine 300 U/mL (0.4 U/kg, evening). Methodological differences and differences in bioequivalence that may explain these discrepancies are discussed. CONCLUSIONS: Compared with earlier insulin analogues, second-generation basal insulins have improved pharmacokinetic/pharmacodynamic profiles that translate into clinical benefits, primarily reduced nocturnal-hypoglycaemia risk. Additional head-to-head comparisons of insulin degludec and insulin glargine 300 U/mL at bioequivalent doses, utilising continuous glucose monitoring and/or real-world evidence, are required to elucidate the differences in their pharmacological and clinical profiles.


Subject(s)
Insulin Glargine/administration & dosage , Insulin Glargine/pharmacokinetics , Insulin, Long-Acting/administration & dosage , Insulin, Long-Acting/pharmacokinetics , Blood Glucose/drug effects , Blood Glucose/metabolism , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/metabolism , Dose-Response Relationship, Drug , Humans , Hypoglycemia/chemically induced , Hypoglycemia/epidemiology , Hypoglycemia/metabolism , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Hypoglycemic Agents/pharmacokinetics , Insulin Glargine/adverse effects , Insulin, Long-Acting/adverse effects , Prognosis
8.
Diabet Med ; 35(7): 846-854, 2018 07.
Article in English | MEDLINE | ID: mdl-29577410

ABSTRACT

AIMS: To assess adult diabetes care providers' current transition practices, knowledge about transition care, and perceived barriers to implementation of best practices in transition care for emerging adults with Type 1 diabetes mellitus. METHODS: We administered a 38-item web-based survey to adult diabetes care providers identified through the Québec Endocrinologist Medical Association and Diabetes Québec. RESULTS: Fifty-three physicians responded (35%). Fewer than half of all respondents (46%) were familiar with the American Diabetes Association's transition care position statement. Approximately one-third of respondents reported a gap of >6 months between paediatric and adult diabetes care. Most (83%) believed communication with the paediatric team was adequate; however, only 56% reported receiving a medical summary and 2% a psychosocial summary from the paediatric provider. Respondents believed that the paediatric team should improve emerging adults' preparation for transition care by developing their self-management skills and improve teaching about the differences between paediatric and adult-oriented care. Only 31% had a system for identifying emerging adults lost to follow-up in adult care. Perceived barriers included difficulty accessing psychosocial services, emerging adults' lack of motivation, and inadequate transition preparation. Most (87%) were interested in having additional resources, including a self-care management tool and a registry to track those lost to follow-up. CONCLUSIONS: Our findings highlight the need to better engage adult care providers into transition care practices. Despite adult physicians' interest in transition care, implementation of transition care recommendations and resources in clinical care remains limited. Enhanced efforts are needed to improve access to mental health services within the adult healthcare setting.


Subject(s)
Attitude of Health Personnel , Communication , Diabetes Mellitus, Type 1/therapy , Endocrinology , Pediatrics , Transition to Adult Care , Adult , Cross-Sectional Studies , Female , Health Services Accessibility , Humans , Interprofessional Relations , Lost to Follow-Up , Male , Middle Aged , Motivation , Psychosocial Support Systems , Quebec , Self Care , Surveys and Questionnaires
9.
Proc Natl Acad Sci U S A ; 114(10): E1913-E1922, 2017 03 07.
Article in English | MEDLINE | ID: mdl-28228521

ABSTRACT

Temporal collinearity is often considered the main force preserving Hox gene clusters in animal genomes. Studies that combine genomic and gene expression data are scarce, however, particularly in invertebrates like the Lophotrochozoa. As a result, the temporal collinearity hypothesis is currently built on poorly supported foundations. Here we characterize the complement, cluster, and expression of Hox genes in two brachiopod species, Terebratalia transversa and Novocrania anomalaT. transversa has a split cluster with 10 genes (lab, pb, Hox3, Dfd, Scr, Lox5, Antp, Lox4, Post2, and Post1), whereas N. anomala has 9 genes (apparently missing Post1). Our in situ hybridization, real-time quantitative PCR, and stage-specific transcriptomic analyses show that brachiopod Hox genes are neither strictly temporally nor spatially collinear; only pb (in T. transversa), Hox3 (in both brachiopods), and Dfd (in both brachiopods) show staggered mesodermal expression. Thus, our findings support the idea that temporal collinearity might contribute to keeping Hox genes clustered. Remarkably, expression of the Hox genes in both brachiopod species demonstrates cooption of Hox genes in the chaetae and shell fields, two major lophotrochozoan morphological novelties. The shared and specific expression of Hox genes, together with Arx, Zic, and Notch pathway components in chaetae and shell fields in brachiopods, mollusks, and annelids provide molecular evidence supporting the conservation of the molecular basis for these lophotrochozoan hallmarks.


Subject(s)
Annelida/genetics , Homeodomain Proteins/genetics , Multigene Family/genetics , Phylogeny , Amino Acid Sequence/genetics , Animals , Gene Expression Regulation/genetics , In Situ Hybridization
10.
Nat Ecol Evol ; 1(1): 5, 2016 Dec 05.
Article in English | MEDLINE | ID: mdl-28812551

ABSTRACT

The mouth opening of bilaterian animals develops either separate from (deuterostomy) or connected to (protostomy) the embryonic blastopore, the site of endomesoderm internalization. Although this distinction preluded the classification of bilaterian animals in Deuterostomia and Protostomia, and has influenced major scenarios of bilaterian evolution, the developmental basis for the appearance of these different embryonic patterns remains unclear. To identify the underlying mechanisms, we compared the development of two brachiopod species that show deuterostomy (Novocrania anomala) and protostomy (Terebratalia transversa), respectively. We show that the differential activity of Wnt signalling, together with the timing and location of mesoderm formation, correlate with the differential behaviour and fate of the blastopore. We further assess these principles in the spiral-cleaving group Annelida, and propose that the developmental relationships of mouth and blastoporal openings are secondary by-products of variations in axial and mesoderm development. This challenges the previous evolutionary emphasis on extant blastoporal behaviours to explain the origin and diversification of bilaterian animals.

11.
PLoS Genet ; 11(12): e1005730, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26684323

ABSTRACT

A main challenge of modern biology is to understand how specific constellations of genes are activated to differentiate cells and give rise to distinct tissues. This study focuses on elucidating how gene expression is initiated in the notochord, an axial structure that provides support and patterning signals to embryos of humans and all other chordates. Although numerous notochord genes have been identified, the regulatory DNAs that orchestrate development and propel evolution of this structure by eliciting notochord gene expression remain mostly uncharted, and the information on their configuration and recurrence is still quite fragmentary. Here we used the simple chordate Ciona for a systematic analysis of notochord cis-regulatory modules (CRMs), and investigated their composition, architectural constraints, predictive ability and evolutionary conservation. We found that most Ciona notochord CRMs relied upon variable combinations of binding sites for the transcription factors Brachyury and/or Foxa2, which can act either synergistically or independently from one another. Notably, one of these CRMs contains a Brachyury binding site juxtaposed to an (AC) microsatellite, an unusual arrangement also found in Brachyury-bound regulatory regions in mouse. In contrast, different subsets of CRMs relied upon binding sites for transcription factors of widely diverse families. Surprisingly, we found that neither intra-genomic nor interspecific conservation of binding sites were reliably predictive hallmarks of notochord CRMs. We propose that rather than obeying a rigid sequence-based cis-regulatory code, most notochord CRMs are rather unique. Yet, this study uncovered essential elements recurrently used by divergent chordates as basic building blocks for notochord CRMs.


Subject(s)
Fetal Proteins/genetics , Hepatocyte Nuclear Factor 3-beta/genetics , Notochord/growth & development , Regulatory Sequences, Nucleic Acid/genetics , T-Box Domain Proteins/genetics , Animals , Binding Sites , Body Patterning/genetics , Ciona intestinalis/genetics , Ciona intestinalis/growth & development , Gene Expression Regulation, Developmental , Genome , Mice
12.
Evodevo ; 6: 10, 2015.
Article in English | MEDLINE | ID: mdl-25897375

ABSTRACT

BACKGROUND: Brachiopods undergo radial cleavage, which is distinct from the stereotyped development of closely related spiralian taxa. The mesoderm has been inferred to derive from the archenteron walls following gastrulation, and the primary mesoderm derivative in the larva is a complex musculature. To investigate the specification and differentiation of the mesoderm in the articulate brachiopod Terebratalia transversa, we have identified orthologs of genes involved in mesoderm development in other taxa and investigated their spatial and temporal expression during the embryonic and larval development of T. transversa. RESULTS: Orthologs of 17 developmental regulatory genes with roles in the development of the mesoderm in other bilaterian animals were found to be expressed in the developing mesoderm of T. transversa. Five genes, Tt.twist, Tt.GATA456, Tt.dachshund, Tt.mPrx, and Tt.NK1, were found to have expression throughout the archenteron wall at the radial gastrula stage, shortly after the initiation of gastrulation. Three additional genes, Tt.Pax1/9, Tt.MyoD, and Tt.Six1/2, showed expression at this stage in only a portion of the archenteron wall. Tt.eya, Tt.FoxC, Tt.FoxF, Tt.Mox, Tt.paraxis, Tt.Limpet, and Tt.Mef2 all showed initial mesodermal expression during later gastrula or early larval stages. At the late larval stage, Tt.dachshund, Tt.Limpet, and Tt.Mef2 showed expression in nearly all mesoderm cells, while all other genes were localized to specific regions of the mesoderm. Tt.FoxD and Tt.noggin both showed expression in the ventral mesoderm at the larval stages, with gastrula expression patterns in the archenteron roof and blastopore lip, respectively. CONCLUSIONS: Expression analyses support conserved roles for developmental regulators in the specification and differentiation of the mesoderm during the development of T. transversa. Expression of multiple mesodermal factors in the archenteron wall during gastrulation supports previous morphological observations that this region gives rise to larval mesoderm. Localized expression domains during gastrulation and larval development evidence early regionalization of the mesoderm and provide a basis for hypotheses regarding the molecular regulation underlying the complex system of musculature observed in the larva.

13.
Diabetes Obes Metab ; 16(10): 1016-27, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24965700

ABSTRACT

AIM: This study evaluated the efficacy and safety of canagliflozin, a sodium glucose co-transporter 2 inhibitor, in patients with type 2 diabetes mellitus (T2DM) and within a subset of Stage 3 chronic kidney disease (CKD; estimated glomerular filtration rate [eGFR] ≥ 30 and <50 ml/min/1.73 m(2)). METHODS: In this 52-week, randomized, double-blind, placebo-controlled study, patients (N = 269; mean eGFR, 39.4 ml/min/1.73 m(2)) received canagliflozin 100 or 300 mg and placebo once daily. Efficacy endpoints included changes in glycated haemoglobin (HbA1c), fasting plasma glucose (FPG), body weight and systolic blood pressure (BP); adverse events (AEs) were also recorded. RESULTS: At week 52, canagliflozin 100 and 300 mg reduced HbA1c compared with placebo (-0.19, -0.33 and 0.07%, respectively); placebo-subtracted differences (95% confidence interval) were -0.27% (-0.53, 0.001) and -0.41% (-0.68, -0.14). Canagliflozin also lowered FPG, body weight and BP versus placebo. Overall AE incidence was 85.6, 80.9, and 86.7% with canagliflozin 100 and 300 mg and placebo, respectively. Osmotic diuresis-related AEs were more common with both canagliflozin doses, and incidences of urinary tract infections and volume depletion-related AEs were higher with canagliflozin 300 mg versus placebo. Decreases in eGFR (-2.1, -4.0 and -1.6 ml/min/1.73 m(2)) were seen with canagliflozin 100 and 300 mg compared with placebo. Canagliflozin 100 and 300 mg provided median percent reductions in urine albumin to creatinine ratio versus placebo (-16.4, -28.0 and 19.7%). CONCLUSIONS: Canagliflozin improved glycaemic control and was generally well tolerated in patients with T2DM and within a subset of Stage 3 CKD over 52 weeks.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Diabetic Nephropathies/drug therapy , Glucosides/therapeutic use , Hypoglycemic Agents/therapeutic use , Renal Insufficiency, Chronic/drug therapy , Sodium-Glucose Transporter 2 Inhibitors , Thiophenes/therapeutic use , Aged , Blood Glucose/drug effects , Blood Pressure/drug effects , Body Weight/drug effects , Canagliflozin , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/physiopathology , Diabetic Nephropathies/blood , Diabetic Nephropathies/physiopathology , Disease Progression , Double-Blind Method , Drug Administration Schedule , Female , Glomerular Filtration Rate/drug effects , Humans , Male , Renal Insufficiency, Chronic/blood , Renal Insufficiency, Chronic/physiopathology , Sodium-Glucose Transporter 2/drug effects , Treatment Outcome
14.
Dev Genes Evol ; 224(1): 13-24, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24292160

ABSTRACT

The aryl hydrocarbon receptor (AHR) is a member of the basic helix-loop-helix/Per-ARNT-Sim (bHLH-PAS) family of transcription factors and has diverse roles in development, physiology, and environmental sensing in bilaterian animals. Studying the expression of conserved genes and function of proteins in outgroups to protostomes and deuterostomes assists in understanding the antiquity of gene function and deciphering lineage-specific differences in these bilaterian clades. We describe the developmental expression of AHR from the sea anemone Nematostella vectensis and compare its expression with three other members of the bHLH-PAS family (AHR nuclear translocator (ARNT), Cycle, and a proto-Single-Minded/Trachealess). NvAHR expression was highest early in the larval stage with spatial expression in the basal portion of the ectoderm that became increasingly restricted to the oral pole with concentrated expression in tentacles of the juvenile polyp. The other bHLH-PAS genes showed a divergent expression pattern in later larval stages and polyps, in which gene expression was concentrated in the aboral end, with broader expression in the endoderm later in development. In co-immunoprecipitation assays, we found no evidence for heterodimerization of AHR with ARNT, contrary to the conservation of this specific interaction in all bilaterians studied to date. Similar to results with other invertebrate AHRs but in contrast to vertebrate AHRs, NvAHR failed to bind two prototypical xenobiotic AHR ligands (2,3,7,8-tetrachlorodibenzo-p-dioxin, ß-naphthoflavone). Together, our data suggest that AHR's original function in Eumetazoa likely involved developmental patterning, potentially of neural tissue. The role of heterodimerization in the function of AHR may have arisen after the cnidarian-bilaterian ancestor. The absence of xenobiotic binding to NvAHR further supports a hypothesis for a derived role of this protein in chemical sensing within the chordates.


Subject(s)
Cnidaria/genetics , Cnidaria/metabolism , Evolution, Molecular , Receptors, Aryl Hydrocarbon/genetics , Amino Acid Sequence , Animals , Cnidaria/growth & development , Gene Expression Regulation, Developmental , Ligands , Molecular Sequence Data , Receptors, Aryl Hydrocarbon/chemistry , Receptors, Aryl Hydrocarbon/metabolism , Sequence Alignment
15.
PLoS Biol ; 11(10): e1001697, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24204212

ABSTRACT

The appearance of the notochord represented a milestone in Deuterostome evolution. The notochord is necessary for the development of the chordate body plan and for the formation of the vertebral column and numerous organs. It is known that the transcription factor Brachyury is required for notochord formation in all chordates, and that it controls transcription of a large number of target genes. However, studies of the structure of the cis-regulatory modules (CRMs) through which this control is exerted are complicated in vertebrates by the genomic complexity and the pan-mesodermal expression territory of Brachyury. We used the ascidian Ciona, in which the single-copy Brachyury is notochord-specific and CRMs are easily identifiable, to carry out a systematic characterization of Brachyury-downstream notochord CRMs. We found that Ciona Brachyury (Ci-Bra) controls most of its targets directly, through non-palindromic binding sites that function either synergistically or individually to activate early- and middle-onset genes, respectively, while late-onset target CRMs are controlled indirectly, via transcriptional intermediaries. These results illustrate how a transcriptional regulator can efficiently shape a shallow gene regulatory network into a multi-tiered transcriptional output, and provide insights into the mechanisms that establish temporal read-outs of gene expression in a fast-developing chordate embryo.


Subject(s)
Ciona intestinalis/genetics , Fetal Proteins/metabolism , Gene Expression Regulation, Developmental , Notochord/metabolism , T-Box Domain Proteins/metabolism , Animals , Binding Sites , Ciona intestinalis/growth & development , Consensus Sequence/genetics , Notochord/growth & development , Protein Binding/genetics , Regulatory Sequences, Nucleic Acid/genetics , Reproducibility of Results , Species Specificity , Time Factors
16.
Int J Clin Pract ; 67(8): 740-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23869677

ABSTRACT

OBJECTIVE: Barriers to insulin initiation in type 2 diabetes mellitus (T2DM) include fear of treatment complexity and perceived lack of time and resources by primary care physicians. The SOLVE study investigated the effect of insulin initiation on resource utilisation and patient quality of life. METHODS: SOLVE was a 24-week cohort study in 10 countries evaluating the safety and effectiveness of initiating once-daily insulin detemir in patients with T2DM. Patient quality of life was assessed using the Insulin Treatment Appraisal Scale (ITAS). RESULTS: A total of 14,611 (84%) patients completed the 24-week study. During the study, HbA1c improved by 1.3 ± 1.5%. The corresponding insulin dose increased from 13 ± 6 IU (0.16 ± 0.09 IU/kg) at baseline, to 22 ± 16 IU (0.27 ± 0.17 IU/kg) at final visit. FlexPen was the preferred device (63%) for insulin administration. The time taken to teach patients to self-inject and perform dose self-adjustment was 15 ± 13 min and 11 ± 11 min, respectively. The quality of life analysis included 6875 patients. The addition of insulin was associated with an improvement in mean ITAS score [-3.5 (95% CI -3.8, -3.3), p < 0.001]. Physicians reported the use or self-adjustment of insulin detemir as easy or very easy in 79% of participants; and satisfaction with the level of glycaemic control was reported for 74% of patients. CONCLUSIONS: Initiating basal insulin therapy resulted in a substantial decrease in HbA1c and improved patients' perceptions of insulin treatment.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Health Resources/statistics & numerical data , Hypoglycemic Agents/administration & dosage , Insulin, Long-Acting/administration & dosage , Quality of Life , Diabetes Mellitus, Type 2/rehabilitation , Drug Administration Schedule , Female , Humans , Hypoglycemic Agents/adverse effects , Injections, Intradermal , Insulin Detemir , Insulin, Long-Acting/adverse effects , Male , Middle Aged , Patient Acceptance of Health Care/statistics & numerical data , Patient Satisfaction
17.
Integr Comp Biol ; 53(1): 17-26, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23630970

ABSTRACT

Bilaterian photoreceptor cells are characterized by the expression of opsins, signal transduction genes, and ion channels, which together facilitate behavioral responses to light. We have previously identified a ciliary opsin gene from the brachiopod Terebratalia transversa, whose expression in gastrula stage embryos coincides with a photoresponse behavior, suggesting the presence of a functional phototransduction system in these early embryos. To further evaluate the potential for light reception in these embryos, we surveyed transcriptome data to identify phototransduction genes and evaluated their expression. In addition to the previously described ciliary opsin gene, we have identified two Go-class opsins that are also expressed in gastrula stage embryos. Representative members from all classes of Gα-protein genes were also expressed, with a Gα12-class gene being localized in the same anterior ectodermal domain as the opsin transcripts. Both CNG-class and TRP-class ion channels were expressed in the gastrula stage embryos, as were GRK and arrestin genes, which are associated with inhibition of rhodopsin activity. Taken together, these data support the presence of a functional phototransduction system in the early brachiopod embryo.


Subject(s)
Embryo, Nonmammalian/physiology , Invertebrates/embryology , Light Signal Transduction/physiology , Opsins/metabolism , Animals , Cloning, Molecular , Embryo, Nonmammalian/metabolism , Gene Expression Profiling , In Situ Hybridization , Invertebrates/metabolism , Opsins/genetics , Washington
18.
Diabetes Obes Metab ; 15(5): 463-73, 2013 May.
Article in English | MEDLINE | ID: mdl-23464594

ABSTRACT

AIMS: Canagliflozin is a sodium glucose co-transporter 2 inhibitor in development for treatment of type 2 diabetes mellitus (T2DM). This study evaluated the efficacy and safety of canagliflozin in subjects with T2DM and stage 3 chronic kidney disease [CKD; estimated glomerular filtration rate (eGFR) ≥30 and <50 ml/min/1.73 m(2)]. METHODS: In this randomized, double-blind, placebo-controlled, phase 3 trial, subjects (N = 269) received canagliflozin 100 or 300 mg or placebo daily. The primary efficacy endpoint was change from baseline in HbA1c at week 26. Prespecified secondary endpoints were change in fasting plasma glucose (FPG) and proportion of subjects reaching HbA1c <7.0%. Safety was assessed based on adverse event (AE) reports; renal safety parameters (e.g. eGFR, blood urea nitrogen and albumin/creatinine ratio) were also evaluated. RESULTS: Both canagliflozin 100 and 300 mg reduced HbA1c from baseline compared with placebo at week 26 (-0.33, -0.44 and -0.03%; p < 0.05). Numerical reductions in FPG and higher proportions of subjects reaching HbA1c < 7.0% were observed with canagliflozin 100 and 300 mg versus placebo (27.3, 32.6 and 17.2%). Overall AE rates were similar for canagliflozin 100 and 300 mg and placebo (78.9, 74.2 and 74.4%). Slightly higher rates of urinary tract infections and AEs related to osmotic diuresis and reduced intravascular volume were observed with canagliflozin 300 mg compared with other groups. Transient changes in renal function parameters that trended towards baseline over 26 weeks were observed with canagliflozin. CONCLUSION: Canagliflozin improved glycaemic control and was generally well tolerated in subjects with T2DM and Stage 3 CKD.


Subject(s)
Body Weight/drug effects , Diabetes Mellitus, Type 2/drug therapy , Glomerular Filtration Rate/drug effects , Glucosides/therapeutic use , Hypoglycemic Agents/therapeutic use , Renal Insufficiency, Chronic/drug therapy , Sodium-Glucose Transporter 2 Inhibitors , Thiophenes/therapeutic use , Aged , Biomarkers/blood , Blood Glucose/drug effects , Blood Glucose/metabolism , Canagliflozin , Comorbidity , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/physiopathology , Disease Progression , Diuresis/drug effects , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Glucosides/administration & dosage , Glycated Hemoglobin/drug effects , Glycated Hemoglobin/metabolism , Humans , Hypoglycemic Agents/administration & dosage , Male , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/physiopathology , Sodium-Glucose Transporter 2/blood , Sodium-Glucose Transporter 2/drug effects , Thiophenes/administration & dosage , Treatment Outcome , Urinary Tract Infections/etiology
19.
BMC Dev Biol ; 12: 34, 2012 Dec 04.
Article in English | MEDLINE | ID: mdl-23206430

ABSTRACT

BACKGROUND: The contribution of cell proliferation to regeneration varies greatly between different metazoan models. Planarians rely on pluripotent neoblasts and amphibian limb regeneration depends upon formation of a proliferative blastema, while regeneration in Hydra can occur in the absence of cell proliferation. Recently, the cnidarian Nematostella vectensis has shown potential as a model for studies of regeneration because of the ability to conduct comparative studies of patterning during embryonic development, asexual reproduction, and regeneration. The present study investigates the pattern of cell proliferation during the regeneration of oral structures and the role of cell proliferation in this process. RESULTS: In intact polyps, cell proliferation is observed in both ectodermal and endodermal tissues throughout the entire oral-aboral axis, including in the tentacles and physa. Following bisection, there is initially little change in proliferation at the wound site of the aboral fragment, however, beginning 18 to 24 hours after amputation there is a dramatic increase in cell proliferation at the wound site in the aboral fragment. This elevated level of proliferation is maintained throughout the course or regeneration of oral structures, including the tentacles, the mouth, and the pharynx. Treatments with the cell proliferation inhibitors hydroxyurea and nocodazole demonstrate that cell proliferation is indispensable for the regeneration of oral structures. Although inhibition of regeneration by nocodazole was generally irreversible, secondary amputation reinitiates cell proliferation and regeneration. CONCLUSIONS: The study has found that high levels of cell proliferation characterize the regeneration of oral structures in Nematostella, and that this cell proliferation is necessary for the proper progression of regeneration. Thus, while cell proliferation contributes to regeneration of oral structures in both Nematostella and Hydra, Nematostella lacks the ability to undergo the compensatory morphallactic mode of regeneration that characterizes Hydra. Our results are consistent with amputation activating a quiescent population of mitotically competent stem cells in spatial proximity to the wound site, which form the regenerated structures.


Subject(s)
Cell Proliferation , Regeneration , Sea Anemones/physiology , Animals , Cell Proliferation/drug effects , Hydroxyurea/pharmacology , Morphogenesis , Mouth , Nocodazole/pharmacology , Regeneration/drug effects , Sea Anemones/cytology , Sea Anemones/drug effects , Wound Healing
20.
Diabetes Obes Metab ; 14(12): 1129-36, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22830956

ABSTRACT

AIMS: Evaluate the safety and efficacy of once-daily insulin detemir initiated in routine clinical practice in patients with type 2 diabetes mellitus inadequately controlled with oral hypoglycaemic agents (OHAs). METHODS: This large observational study was conducted in 10 countries. Adverse event data (including hypoglycaemia) and glycaemic control were recorded before and 24 weeks following insulin initiation while patients continued routine clinical management. RESULTS: In this study, 17 374 patients (53% male) were included. Mean pre-insulin values (±s.d.) were: age 62 ± 12 years; body mass index (BMI) 29.3 ± 5.4 kg/m(2); diabetes duration 10 ± 7 years; haemoglobin A1c (HbA1c) 8.9 ± 1.6%. During the study, 27 patients experienced serious adverse drug reaction, severe hypoglycaemic events or both; and there were 31 episodes of severe hypoglycaemia in 21 patients. After 24 weeks, HbA1c was 7.5 ± 1.2% (change of -1.3%; p < 0.001) and mean weight change was -0.6 kg (confidence interval -0.7, -0.5 kg, p < 0.001). Daily insulin dose increased from 13 ± 6 U (0.16 ± 0.09 U/kg) to 22 ± 16 U (0.27 ± 0.17U/kg) by 24 weeks. Multivariate regression analysis identified several independent demographic and treatment predictors of end of study HbA1c. CONCLUSIONS: Addition of once-daily insulin detemir to patients with type 2 diabetes mellitus on OHA therapy resulted in few adverse events, significant improvements in glycaemic control, small reductions in weight and low rates of hypoglycaemia. On the basis of this study, concerns about hypoglycaemia or weight gain should not preclude initiation of basal insulin analogues in patients with poor glycaemic control on OHAs.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/administration & dosage , Insulin, Long-Acting/administration & dosage , Insulin/analogs & derivatives , Aged , Blood Glucose/metabolism , Body Mass Index , Canada/epidemiology , China/epidemiology , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/epidemiology , Drug Administration Schedule , Drug Therapy, Combination , Europe/epidemiology , Female , Glycated Hemoglobin/metabolism , Humans , Insulin/therapeutic use , Insulin Detemir , Male , Middle Aged , Treatment Outcome
SELECTION OF CITATIONS
SEARCH DETAIL
...