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1.
mSystems ; 9(6): e0113523, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38747602

RESUMO

Sulfur-oxidizing bacteria (SOB) have developed distinct ecological strategies to obtain reduced sulfur compounds for growth. These range from specialists that can only use a limited range of reduced sulfur compounds to generalists that can use many different forms as electron donors. Forming intimate symbioses with animal hosts is another highly successful ecological strategy for SOB, as animals, through their behavior and physiology, can enable access to sulfur compounds. Symbioses have evolved multiple times in a range of animal hosts and from several lineages of SOB. They have successfully colonized a wide range of habitats, from seagrass beds to hydrothermal vents, with varying availability of symbiont energy sources. Our extensive analyses of sulfur transformation pathways in 234 genomes of symbiotic and free-living SOB revealed widespread conservation in metabolic pathways for sulfur oxidation in symbionts from different host species and environments, raising the question of how they have adapted to such a wide range of distinct habitats. We discovered a gene family expansion of soxY in these genomes, with up to five distinct copies per genome. Symbionts harboring only the "canonical" soxY were typically ecological "specialists" that are associated with specific host subfamilies or environments (e.g., hydrothermal vents, mangroves). Conversely, symbionts with multiple divergent soxY genes formed versatile associations across diverse hosts in various marine environments. We hypothesize that expansion and diversification of the soxY gene family could be one genomic mechanism supporting the metabolic flexibility of symbiotic SOB enabling them and their hosts to thrive in a range of different and dynamic environments.IMPORTANCESulfur metabolism is thought to be one of the most ancient mechanisms for energy generation in microorganisms. A diverse range of microorganisms today rely on sulfur oxidation for their metabolism. They can be free-living, or they can live in symbiosis with animal hosts, where they power entire ecosystems in the absence of light, such as in the deep sea. In the millions of years since they evolved, sulfur-oxidizing bacteria have adopted several highly successful strategies; some are ecological "specialists," and some are "generalists," but which genetic features underpin these ecological strategies are not well understood. We discovered a gene family that has become expanded in those species that also seem to be "generalists," revealing that duplication, repurposing, and reshuffling existing genes can be a powerful mechanism driving ecological lifestyle shifts.


Assuntos
Oxirredução , Sulfetos , Simbiose , Animais , Adaptação Fisiológica/genética , Bactérias/genética , Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Fontes Hidrotermais/microbiologia , Família Multigênica , Filogenia , Sulfetos/metabolismo , Enxofre/metabolismo , Simbiose/genética , Bivalves
2.
R Soc Open Sci ; 10(5): 221466, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37181791

RESUMO

Historically, the role of aggression in the social lives of animals overwhelmingly focused on males. In recent years, however, female-female aggression in vertebrates, particularly lizards, has received increasing attention. This growing body of literature shows both similarities and differences to aggressive behaviours between males. Here, we document female-female aggression in captive Gila monsters (Heloderma suspectum). Based on four unique dyadic trials (eight adult female subjects), we developed a qualitative ethogram. Unexpected and most intriguing were the prevalence and intensity of aggressive acts that included brief and sustained biting, envenomation, and lateral rotation (i.e. rolling of body while holding onto opponent with closed jaws). Given specific behavioural acts (i.e. biting) and the results of bite-force experiments, we postulate that osteoderms (bony deposits in the skin) offer some degree of protection and reduce the likelihood of serious injury during female-female fights. Male-male contests in H. suspectum, in contrast, are more ritualized, and biting is rarely reported. Female-female aggression in other lizards has a role in territoriality, courtship tactics, and nest and offspring guarding. Future behavioural research on aggression in female Gila monsters is warranted to test these and other hypotheses in the laboratory and field.

3.
Microbiol Spectr ; 10(3): e0240821, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35604233

RESUMO

Animal venoms are considered sterile sources of antimicrobial compounds with strong membrane-disrupting activity against multidrug-resistant bacteria. However, venomous bite wound infections are common in developing nations. Investigating the envenomation organ and venom microbiota of five snake and two spider species, we observed venom community structures that depend on the host venomous animal species and evidenced recovery of viable microorganisms from black-necked spitting cobra (Naja nigricollis) and Indian ornamental tarantula (Poecilotheria regalis) venoms. Among the bacterial isolates recovered from N. nigricollis, we identified two venom-resistant, novel sequence types of Enterococcus faecalis whose genomes feature 16 virulence genes, indicating infectious potential, and 45 additional genes, nearly half of which improve bacterial membrane integrity. Our findings challenge the dogma of venom sterility and indicate an increased primary infection risk in the clinical management of venomous animal bite wounds. IMPORTANCE Notwithstanding their 3 to 5% mortality, the 2.7 million envenomation-related injuries occurring annually-predominantly across Africa, Asia, and Latin America-are also major causes of morbidity. Venom toxin-damaged tissue will develop infections in some 75% of envenomation victims, with E. faecalis being a common culprit of disease; however, such infections are generally considered to be independent of envenomation. Here, we provide evidence on venom microbiota across snakes and arachnida and report on the convergent evolution mechanisms that can facilitate adaptation to black-necked cobra venom in two independent E. faecalis strains, easily misidentified by biochemical diagnostics. Therefore, since inoculation with viable and virulence gene-harboring bacteria can occur during envenomation, acute infection risk management following envenomation is warranted, particularly for immunocompromised and malnourished victims in resource-limited settings. These results shed light on how bacteria evolve for survival in one of the most extreme environments on Earth and how venomous bites must be also treated for infections.


Assuntos
Aracnídeos , Peçonhas , Animais , Ásia , Bactérias/genética , Serpentes
4.
PLoS One ; 16(7): e0254248, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34242292

RESUMO

We have modified the periplasmic Escherichia coli glucose/galactose binding protein (GBP) and labelled with environmentally sensitive fluorophores to further explore its potential as a sensor for the evaluation of glucose concentration in airway surface liquid (ASL). We identified E149C/A213R GBP labelled with N,N'-Dimethyl-N-(iodoacetyl)-N'-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)ethylenediamine (IANBD, emission wavelength maximum 536nm) with a Kd for D-glucose of 1.02mM and a fluorescence dynamic range of 5.8. This sensor was specific for D-glucose and exhibited fluorescence stability in experiments for several hours. The use of E149C/A213R GBP-IANBD in the ASL of airway cells grown at air-liquid-interface (ALI) detected an increase in glucose concentration 10 minutes after raising basolateral glucose from 5 to 15mM. This sensor also reported a greater change in ASL glucose concentration in response to increased basolateral glucose in H441 airway cells compared to human bronchial epithelial cells (HBEC) and there was less variability with HBEC data than that of H441 indicating that HBEC more effectively regulate glucose movement into the ASL. The sensor detected glucose in bronchoalveolar lavage fluid (BALf) from diabetic db/db mice but not normoglycaemic wildtype mice, indicating limited sensitivity of the sensor at glucose concentrations <50µM. Using nasal inhalation of the sensor and spectral unmixing to generate images, E149C/A213R GBP-IANBD fluorescence was detected in luminal regions of cryosections of the murine distal lung that was greater in db/db than wildtype mice. In conclusion, this sensor provides a useful tool for further development to measure luminal glucose concentration in models of lung/airway to explore how this may change in disease.


Assuntos
Técnicas Biossensoriais , Glucose , Animais , Proteínas de Ligação ao Cálcio , Células Epiteliais , Camundongos , Proteínas de Transporte de Monossacarídeos , Proteínas Periplásmicas de Ligação
5.
Zookeys ; 899: 109-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31875090

RESUMO

Species identified as Pillucina are paraphyletic in molecular analyses and a new generic name, Rugalucina, is introduced for a complex of three similar species Rugalucina angela from the northern Indian Ocean and Red Sea, R. vietnamica from South East Asia, and R. munda from northern and north eastern Australia. Lucina concinna from the Red Sea, previously synonymised with P. vietnamica/angela is recognised as a Rugalucina-like species but with a very short anterior adductor scar. Divaricella cypselis from Karachi is similarly now recognised as a distinct species, probably related to Rugalucina but with oblique commarginal sculpture and a short adductor scar. A group of minute Indo-West Pacific lucinids with highly unusual multi-cuspate lateral teeth and previously classified as Pillucina are separated under a new genus Pusillolucina gen. nov., with the description of three new species P. arabica, P. africana, and P. biritika from the Arabian Gulf, Mozambique, and Madagascar. Finally, a new genus, Notocina, is introduced for the small southern Atlantic species, Epicodakia falklandica, shown in molecular analyses to be misplaced at subfamily level and now classified in Lucininae and not Codakiinae with Epicodakia.

6.
Zookeys ; (707): 1-46, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29118626

RESUMO

We present the first DNA taxonomy publication on abyssal Mollusca from the Clarion-Clipperton Zone (CCZ), central Pacific ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise 'AB01' to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration area 'UK-1' in the eastern CCZ. This is the third paper in a series to provide regional taxonomic data for a region that is undergoing intense deep-sea mineral exploration for high-grade polymetallic nodules. Taxonomic data are presented for 21 species from 42 records identified by a combination of morphological and genetic data, including molecular phylogenetic analyses. These included 3 heterodont bivalves, 5 protobranch bivalves, 4 pteriomorph bivalves, 1 caudofoveate, 1 monoplacophoran, 1 polyplacophoran, 4 scaphopods and 2 solenogastres. Gastropoda were recovered but will be the subject of a future study. Seven taxa matched published morphological descriptions for species with deep Pacific type localities, and our sequences provide the first genetic data for these taxa. One taxon morphologically matched a known cosmopolitan species but with a type locality in a different ocean basin and was assigned the open nomenclature 'cf' as a precautionary approach in taxon assignments to avoid over-estimating species ranges. One taxon is here described as a new species, Ledella knudseni sp. n. For the remaining 12 taxa, we have determined them to be potentially new species, for which we make the raw data, imagery and vouchers available for future taxonomic study. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections.

7.
Br J Pharmacol ; 174(9): 836-847, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28192604

RESUMO

BACKGROUND AND PURPOSE: Hyperglycaemia increases glucose concentrations in airway surface liquid and increases the risk of pulmonary Pseudomonas aeruginosa infection. We determined whether reduction of blood and airway glucose concentrations by the anti-diabetic drug dapagliflozin could reduce P. aeruginosa growth/survival in the lungs of diabetic mice. EXPERIMENTAL APPROACH: The effect of dapagliflozin on blood and airway glucose concentration, the inflammatory response and infection were investigated in C57BL/6J (wild type, WT) or leptin receptor-deficient (db/db) mice, treated orally with dapagliflozin prior to intranasal dosing with LPS or inoculation with P. aeruginosa. Pulmonary glucose transport and fluid absorption were investigated in Wistar rats using the perfused fluid-filled lung technique. KEY RESULTS: Fasting blood, airway glucose and lactate concentrations were elevated in the db/db mouse lung. LPS challenge increased inflammatory cells in bronchoalveolar lavage fluid from WT and db/db mice with and without dapagliflozin treatment. P. aeruginosa colony-forming units (CFU) were increased in db/db lungs. Pretreatment with dapagliflozin reduced blood and bronchoalveolar lavage glucose concentrations and P. aeruginosa CFU in db/db mice towards those seen in WT. Dapagliflozin had no adverse effects on the inflammatory response in the mouse or pulmonary glucose transport or fluid absorption in the rat lung. CONCLUSION AND IMPLICATIONS: Pharmacological lowering of blood glucose with dapagliflozin effectively reduced P. aeruginosa infection in the lungs of diabetic mice and had no adverse pulmonary effects in the rat. Dapagliflozin has potential to reduce the use, or augment the effect, of antimicrobials in the prevention or treatment of pulmonary infection.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Glucosídeos/uso terapêutico , Infecções por Pseudomonas/sangue , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Animais , Compostos Benzidrílicos/farmacologia , Glicemia/metabolismo , Líquido da Lavagem Broncoalveolar , Diabetes Mellitus Experimental/sangue , Glucosídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ratos , Ratos Wistar , Proteínas de Transporte de Sódio-Glucose/farmacologia , Proteínas de Transporte de Sódio-Glucose/uso terapêutico
8.
J Pulm Respir Med ; 2017(1)2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29938126

RESUMO

Elevation of blood glucose results in increased glucose in the fluid that lines the surface of the airways and this is associated with an increased susceptibility to infection with respiratory pathogens. Infection induces an inflammatory response in the lung, but how this is altered by hyperglycemia and how this affects glucose, lactate and cytokine concentrations in the airway surface liquid is not understood. We used Wild Type (WT) and glucokinase heterozygote (GK+/-) mice to investigate the effect of hyperglycemia, with and without LPS-induced inflammatory responses, on airway glucose, lactate, inflammatory cells and cytokines measured in Bronchoalveolar Lavage Fluid (BALF). We found that glucose and lactate concentrations in BALF were elevated in GK+/- compared to WT mice and that there was a direct correlation between blood glucose and BALF glucose concentrations. LPS challenge increased BALF inflammatory cell numbers and this correlated with decreased glucose and increased lactate concentrations although the effect was less in GK+/- compared to WT mice. All cytokines measured (except IL-2) increased in BALF with LPS challenge. However, concentrations of TNFα, INFγ, IL-1ß and IL-2 were less in GK+/- compared to WT mice. This study shows that the normal glucose/lactate environment of the airway surface liquid is altered by hyperglycemia and the inflammatory response. These data indicate that inflammatory cells utilize BALF glucose and that production of lactate and cytokines is compromised in hyperglycemic GK+/- mice.

9.
Mol Phylogenet Evol ; 107: 191-208, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27840226

RESUMO

The systematics of the molluscan class Bivalvia are explored using a 5-gene Sanger-based approach including the largest taxon sampling to date, encompassing 219 ingroup species spanning 93 (or 82%) of the 113 currently accepted bivalve families. This study was designed to populate the bivalve Tree of Life at the family level and to place many genera into a clear phylogenetic context, but also pointing to several major clades where taxonomic work is sorely needed. Despite not recovering monophyly of Bivalvia or Protobranchia-as in most previous Sanger-based approaches to bivalve phylogeny-our study provides increased resolution in many higher-level clades, and supports the monophyly of Autobranchia, Pteriomorphia, Heteroconchia, Palaeoheterodonta, Heterodonta, Archiheterodonta, Euheterodonta, Anomalodesmata, Imparidentia, and Neoheterodontei, in addition to many other lower clades. However, deep nodes within some of these clades, especially Pteriomorphia and Imparidentia, could not be resolved with confidence. In addition, many families are not supported, and several are supported as non-monophyletic, including Malletiidae, Nuculanidae, Yoldiidae, Malleidae, Pteriidae, Arcidae, Propeamussiidae, Iridinidae, Carditidae, Myochamidae, Lyonsiidae, Pandoridae, Montacutidae, Galeommatidae, Tellinidae, Semelidae, Psammobiidae, Donacidae, Mactridae, and Cyrenidae; Veneridae is paraphyletic with respect to Chamidae, although this result appears to be an artifact. The denser sampling however allowed testing specific placement of species, showing, for example, that the unusual Australian Plebidonax deltoides is not a member of Donacidae and instead nests within Psammobiidae, suggesting that major revision of Tellinoidea may be required. We also showed that Cleidothaerus is sister group to the cementing member of Myochamidae, suggesting that Cleidothaeridae may not be a valid family and that cementation in Cleidothaerus and Myochama may have had a single origin. These results highlight the need for an integrative approach including as many genera as possible, and that the monophyly and relationships of many families require detailed reassessment. NGS approaches may be able to resolve the most recalcitrant nodes in the near future.


Assuntos
Bivalves/classificação , Bivalves/genética , Filogenia , Análise de Sequência de DNA/métodos , Animais , Teorema de Bayes , Funções Verossimilhança
10.
Zootaxa ; 4196(3): zootaxa.4196.3.2, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27988662

RESUMO

A new molecular phylogeny of the Lucinidae using 18S and 28S rRNA and cytochrome b genes includes many species from the tropical Western Atlantic as well as additional taxa from the Indo-West Pacific. This study provides a phylogenetic framework for a new taxonomy of tropical Western Atlantic lucinids. The analysis confirmed five major clades-Pegophyseminae, Leucosphaerinae, Myrteinae, Codakiinae and Lucininae, with Monitilorinae and Fimbriinae represented by single species. The Leucosphaerinae are expanded and include Callucina winckworthi and the W. Atlantic Myrtina pristiphora that groups with several Indo-West Pacific Myrtina species. Within the Codakiinae two abundant species of Ctena from the Western Atlantic with similar shells are discriminated as C. orbiculata and C. imbricatula, while in the Indo-West Pacific Ctena bella is a probable species complex. The Lucininae is the most species rich and disparate subfamily with several subclades apparent. Three species of Lucina are recognized in the W. Atlantic L. aurantia, L. pensylvanica and L. roquesana. Pleurolucina groups near to Cavilinga and Lucina, while Lucinisca muricata is more closely related to the E. Pacific L. fenestrata than to the Atlantic L. nassula. A new species of Parvilucina is identified from molecular analyses having been confounded with Parvilucina pectinata but differs in ligament structure. Also, the former Parvilucina clenchi is more distant and assigned to Guyanella.


Assuntos
Bivalves/classificação , Bivalves/genética , Filogenia , Distribuição Animal , Animais , Oceano Atlântico , Bivalves/fisiologia , Citocromos b/genética , Evolução Molecular , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética
11.
Zookeys ; (620): 1-19, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27853404

RESUMO

A new shallow water species of the lucinid bivalve Pleurolucina is described from Curaçao in the southern Caribbean Sea and compared with known species of the genus from the western Atlantic and eastern Pacific Oceans. Although confused with the Floridian species Pleurolucina leucocyma, it is most similar to the eastern Pacific Pleurolucina undata. As in all studied lucinids, the new species possesses symbiotic bacteria housed in the ctenidia. The shell microstructure is unusual with repeated and intercalated conchiolin layers that have sublayers of 'tulip-shaped' calcareous spherules. Predatory drillings by naticid gastropods frequently terminate at the conchiolin layers.

12.
Proc Biol Sci ; 282(1801): 20142332, 2015 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-25589608

RESUMO

Bivalves are an ancient and ubiquitous group of aquatic invertebrates with an estimated 10 000-20 000 living species. They are economically significant as a human food source, and ecologically important given their biomass and effects on communities. Their phylogenetic relationships have been studied for decades, and their unparalleled fossil record extends from the Cambrian to the Recent. Nevertheless, a robustly supported phylogeny of the deepest nodes, needed to fully exploit the bivalves as a model for testing macroevolutionary theories, is lacking. Here, we present the first phylogenomic approach for this important group of molluscs, including novel transcriptomic data for 31 bivalves obtained through an RNA-seq approach, and analyse these data with published genomes and transcriptomes of other bivalves plus outgroups. Our results provide a well-resolved, robust phylogenetic backbone for Bivalvia with all major lineages delineated, addressing long-standing questions about the monophyly of Protobranchia and Heterodonta, and resolving the position of particular groups such as Palaeoheterodonta, Archiheterodonta and Anomalodesmata. This now fully resolved backbone demonstrates that genomic approaches using hundreds of genes are feasible for resolving phylogenetic questions in bivalves and other animals.


Assuntos
Bivalves/classificação , Bivalves/genética , Transcriptoma , Animais , DNA Complementar/genética , Dados de Sequência Molecular , Filogenia , Análise de Sequência de RNA
13.
Zookeys ; (326): 69-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24039537

RESUMO

Four new species and a new genus of lucinid bivalves are described from shallow and deeper waters in the Indian and West Pacific Oceans. The new genus Scabrilucina (subfamily Lucininae) includes the little-known Scabrilucina victorialis (Melvill, 1899) from the Arabian Sea and Scabrilucina vitrea (Deshayes, 1844) from the Andaman Sea as well as a new species Scabrilucina melvilli from the Torres Strait off northeastern Australia. Ferrocina brunei new species (Lucininae) was recovered from 60 m near oil drilling activities off Borneo; its anatomy confirmed the presence of symbiotic bacteria. Two unusual deeper water species of Leucosphaerinae are described, both species included in on-going molecular analyses; Gonimyrtea ferruginea from 400-650 m in the southwest Pacific and Myrtina reflexa from 200-825 m off Zanzibar and Madagascar.

14.
Transplantation ; 95(10): 1263-9, 2013 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-23507700

RESUMO

BACKGROUND: Peripancreatic fluid collections (PPFC) are a serious complication after simultaneous pancreas-kidney transplantation (SPKTx). METHODS: Retrospective study for all 223 SPKTx performed from December 8, 1996, to October 10, 2011, to evaluate the risk factors (RF) and impact of PPFCs on outcomes was conducted. RESULTS: Clinically significant PPFCs were seen in 36 (16%) cases, all within 3 months after transplantation. Radiologic drainage resolved 2 (6%) cases, and 34 required laparotomy (mean [SD], 4 [7]). Compared with the non-PPFC group (n=186), the PPFC group had similar patient and total kidney graft survivals but significantly lower total pancreas survival (68% vs. 85%) and greater incidence of infections (75% vs. 46%, all P<0.05) at 5 years. PPFCs were associated with early graft pancreatitis in 18 (50%), pancreatic fistula in 20 (56%, 9 with obvious duodenal stump leak) and infection in the collection in 20 (56%) cases. Comparison of PPFCs with pancreas graft loss to the PPFCs with surviving grafts showed that the incidence of pancreatic fistula was greater in the former (90% pancreas graft loss vs. 42% pancreas graft survival, P<0.01). Binary logistic regression analysis of RF for developing PPFC showed a donor age >30 years to be significant (P=0.03; odds ratio, 3.4; confidence interval, 1.1-10.5) and a trend of association with donor body mass index >30 and pancreas cold ischemia time greater than 12 hr. CONCLUSIONS: PPFCs are associated with significant reduction in pancreas allograft survival and impact resource use. Donor age >30 years is a significant RF for their development. PPFCs associated with pancreatic fistula carry a greater risk for pancreas graft loss.


Assuntos
Transplante de Rim/efeitos adversos , Transplante de Pâncreas/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adolescente , Adulto , Feminino , Rejeição de Enxerto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fístula Pancreática/etiologia , Pancreatite/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Risco
15.
Mol Phylogenet Evol ; 65(1): 64-74, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22659514

RESUMO

Revived interest in molluscan phylogeny has resulted in a torrent of molecular sequence data from phylogenetic, mitogenomic, and phylogenomic studies. Despite recent progress, basal relationships of the class Bivalvia remain contentious, owing to conflicting morphological and molecular hypotheses. Marked incongruity of phylogenetic signal in datasets heavily represented by nuclear ribosomal genes versus mitochondrial genes has also impeded consensus on the type of molecular data best suited for investigating bivalve relationships. To arbitrate conflicting phylogenetic hypotheses, we evaluated the utility of four nuclear protein-encoding genes-ATP synthase ß, elongation factor-1α, myosin heavy chain type II, and RNA polymerase II-for resolving the basal relationships of Bivalvia. We sampled all five major lineages of bivalves (Archiheterodonta, Euheterodonta [including Anomalodesmata], Palaeoheterodonta, Protobranchia, and Pteriomorphia) and inferred relationships using maximum likelihood and Bayesian approaches. To investigate the robustness of the phylogenetic signal embedded in the data, we implemented additional datasets wherein length variability and/or third codon positions were eliminated. Results obtained include (a) the clade (Nuculanida+Opponobranchia), i.e., the traditionally defined Protobranchia; (b) the monophyly of Pteriomorphia; (c) the clade (Archiheterodonta+Palaeoheterodonta); (d) the monophyly of the traditionally defined Euheterodonta (including Anomalodesmata); and (e) the monophyly of Heteroconchia, i.e., (Palaeoheterodonta+Archiheterodonta+Euheterodonta). The stability of the basal tree topology to dataset manipulation is indicative of signal robustness in these four genes. The inferred tree topology corresponds closely to those obtained by datasets dominated by nuclear ribosomal genes (18S rRNA and 28S rRNA), controverting recent taxonomic actions based solely upon mitochondrial gene phylogenies.


Assuntos
Bivalves/genética , Proteínas Nucleares/genética , Filogenia , Animais , Teorema de Bayes , Funções Verossimilhança , ATPases Mitocondriais Próton-Translocadoras/genética , Cadeias Pesadas de Miosina/genética , Fator 1 de Elongação de Peptídeos/genética , RNA Polimerase II/genética
16.
Pulm Pharmacol Ther ; 25(3): 223-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22446025

RESUMO

Pulmonary inflammation disorders represent a major healthcare burden, and novel anti-inflammatory agents are critically needed for the treatment of patients unresponsive to current therapies. In vivo animal models play a key role in the preclinical assessment of novel anti-inflammatory compounds. The implementation of streamlined in vivo experimental designs that are time-and cost-efficient, while keeping animal usage low, is a key consideration for drug optimization programs. The Sephadex rat model of pulmonary inflammation captures many pathophysiologic characteristics of clinical asthma and allergy, such as eosinophilic infiltration andinterstitial edema. Using the in vivo Sephadex model, we compared two different study designs that were implemented to screen and select two novel candidate drugs for a drug discovery project. The traditional one-start design, which utilizes few dose-testing groups with many animals per group, was used to select the first candidate drug. Due to tight timelines, the selection process for the second candidate drug had to be optimized, leading to the development of the novel two-start design, an approach whereby dose ranges are optimized in two experimental phases. Here we show that both study designs were comparable in their generation of robust median effective dose values for selected candidate drugs, as represented by similar confidence interval ratios. However, implementation of the two-start design resulted in approximately 50% fewer animals and 50% less time taken to assess the efficacy of an equal number of compounds compared with the one-start design. These results demonstrate that the two-start design is a more efficient experimental approach, and its widespread implementation in drug optimization programs will impact upon the selection process for candidate drugs with regards to time, cost, and animal usage.


Assuntos
Anti-Inflamatórios/farmacologia , Glucocorticoides/farmacologia , Inflamação/tratamento farmacológico , Pneumopatias/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Dextranos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Desenho de Fármacos , Glucocorticoides/administração & dosagem , Inflamação/patologia , Pneumopatias/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Projetos de Pesquisa , Fatores de Tempo
17.
Int Urol Nephrol ; 44(1): 275-81, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21997202

RESUMO

INTRODUCTION: Renal transplant patients are unique in that bone changes occur on a background of pre-existing chronic kidney disease-mineral bone disorder. In a few cases, there is overt hyperparathyroidism manifested by hypercalcaemia. Traditionally, if severe or persistent, this is treated by parathyroidectomy. At our unit, the default surgical operation is total parathyroidectomy without autotransplantation. METHODS: Patient charts for the last three decades were reviewed retrospectively. Twenty-six subjects with functioning renal transplants who underwent parathyroidectomy had biochemistry and clinical information for at least 6 months pre- and post-surgery. The criteria for parathyroidectomy were persistent hypercalcaemia (>2.75 mmol/L) and/or clinical problems (e.g. kidney stones). A 5-year follow-up was available for all 26 subjects and a 9-year follow-up for 20 patients. RESULTS: After surgery, patients were supplemented with 1-α-calcidol. The median preoperative calcium level was 3.10 mmol/L. One month postoperatively, this fell to 2.41 mmol/L. Normocalcaemia was maintained at 5 years (2.40 mmol/L) and at 9 years (2.39 mmol/L), with a calcium-phosphate product of 3.0 mmol(2)/L(2) and median parathyroid hormone level of 12 pg/mL. CONCLUSION: Total parathyroidectomy without autotransplantation in renal transplant patients appears to be protective against persistent and recurrent disease. This is the largest series with the longest follow-up available in the literature of this specific patient population.


Assuntos
Cálcio/sangue , Hiperparatireoidismo/cirurgia , Transplante de Rim , Paratireoidectomia , Distribuição de Qui-Quadrado , Feminino , Seguimentos , Humanos , Hipercalcemia/sangue , Hipercalcemia/etiologia , Hipercalcemia/cirurgia , Hiperparatireoidismo/sangue , Hiperparatireoidismo/complicações , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do Tratamento
18.
PLoS One ; 5(10): e13251, 2010 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-20967263

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease is a progressive lung disease that is punctuated by periods of exacerbations (worsening of symptoms) that are attributable to viral infections. While rhinoviruses are most commonly isolated viruses during episodes of exacerbation, influenza viruses have the potential to become even more problematic with the increased likelihood of an epidemic. METHODOLOGY AND PRINCIPAL FINDINGS: This study examined the impact of current and potential pharmacological targets namely the systemic corticosteroid dexamethasone and the peroxisome proliferator-activated receptor-gamma agonist pioglitazone on the outcome of infection in smoke-exposed mice. C57BL/6 mice were exposed to room air or cigarette smoke for 4 days and subsequently inoculated with an H1N1 influenza A virus. Interventions were delivered daily during the course of infection. We show that smoke-exposed mice have an exacerbated inflammatory response following infection. While smoke exposure did not compromise viral clearance, precision cut lung slices from smoke-exposed mice showed greater expression of CC (MCP-1, -3), and CXC (KC, MIP-2, GCP-2) chemokines compared to controls when stimulated with a viral mimic or influenza A virus. While dexamethasone treatment partially attenuated the inflammatory response in the broncho-alveolar lavage of smoke-exposed, virally-infected animals, viral-induced neutrophilia was steroid insensitive. In contrast to controls, dexamethasone-treated smoke-exposed influenza-infected mice had a worsened health status. Pioglitazone treatment of virally-infected smoke-exposed mice proved more efficacious than the steroid intervention. Further mechanistic evaluation revealed that a deficiency in CCR2 did not improve the inflammatory outcome in smoke-exposed, virally-infected animals. CONCLUSIONS AND SIGNIFICANCE: This animal model of cigarette smoke and H1N1 influenza infection demonstrates that smoke-exposed animals are differentially primed to respond to viral insult. While providing a platform to test pharmacological interventions, this model demonstrates that treating viral exacerbations with alternative anti-inflammatory drugs, such as PPAR-gamma agonists should be further explored since they showed greater efficacy than systemic corticosteroids.


Assuntos
Modelos Animais de Doenças , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar , Animais , Quimiocinas/metabolismo , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/metabolismo , Influenza Humana/virologia , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/agonistas , Pioglitazona , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/virologia , Tiazolidinedionas/farmacologia , Tiazolidinedionas/uso terapêutico
19.
Inflamm Res ; 59(10): 817-25, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20387089

RESUMO

OBJECTIVE: The aim was to create pathological changes in mice relevant to human smoke exposure that can be used to further understand the mechanisms and pathology of smoke-induced inflammatory disease. METHODS: Mice were exposed to tobacco smoke or lipopolysaccharide (LPS) to generate an inflammatory infiltrate within the lungs. RESULTS: Tobacco smoke exposure over a 4 day period led to neutrophilia in the lungs of BALB/c mice. Within the inflammatory exudates, significant changes were also seen in protein levels of IL-1B, IL-6, MIP-2, KC (IL-8) and TIMP-1 as measured by ELISA. Further protein changes, as measured via multiplex analysis revealed increased levels of MMP-9, MDC, LIF and MCP-1, amongst other mediators. Major changes in whole lung tissue gene expression patterns were observed. The neutrophilia seen after smoke exposure was steroid-insensitive, relative to doses of steroid needed to reduce LPS-driven neutrophilia in controls. This exposes pathological switches that are changed upon exposure to tobacco smoke, rendering steroids less effective under these conditions. Challenge of chemokine receptor type 1 (CCR1) KO mice in the tobacco smoke model showed that lack of this gene protected the mice from smoke-induced inflammation. CONCLUSIONS: This suggests the CCR1 receptor has a key role in the pathogenesis of smoke-induced inflammation.


Assuntos
Inflamação/induzido quimicamente , Nicotiana/efeitos adversos , Receptores CCR1/metabolismo , Fumaça/efeitos adversos , Animais , Líquido da Lavagem Broncoalveolar/química , Feminino , Expressão Gênica , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores CCR1/genética , Esteroides/uso terapêutico
20.
Pulm Pharmacol Ther ; 23(5): 376-83, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20382250

RESUMO

Chronic Obstructive Pulmonary Disease (COPD) is a major cause of death in the western world and increasing in prevalence in developing countries. COPD is characterised by irreversible airflow obstruction, loss of lung tissue, reduced quality of life and high rates of mortality. The major cause of COPD is tobacco smoke. The changes in the innate immune system directed by tobacco smoke exposure lead to a pronounced and chronic inflammation in the lung. This in turn leads to other pathological changes including remodelling and destruction of lung tissue. Tobacco smoke exposure also leads to infection of the lung by bacteria and viruses. These, bacteria, viruses and co-infection are key triggers of acute worsening's of COPD termed exacerbations. COPD exacerbations are an additional major factor in the morbidity and mortality within COPD and are also the major healthcare costs associated with the disease. Within this review we discuss the response of the immune system to cigarette smoke exposure and inappropriate harmful responses. Successful treatment strategies will need to balance the positive effects of reducing inflammatory aspects of the disease whilst retaining some of the needed immune responses triggered by tobacco smoke exposure.


Assuntos
Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Risco
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