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1.
J Neurogenet ; 35(1): 1-22, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33164597

RESUMO

Mutations in hundreds of genes cause neurodevelopmental disorders with abnormal motor behavior alongside cognitive deficits. Boys with fragile X syndrome (FXS), a leading monogenic cause of intellectual disability, often display repetitive behaviors, a core feature of autism. By direct observation and manual analysis, we characterized spontaneous-motor-behavior phenotypes of Drosophila dfmr1 mutants, an established model for FXS. We recorded individual 1-day-old adult flies, with mature nervous systems and prior to the onset of aging, in small arenas. We scored behavior using open-source video-annotation software to generate continuous activity timelines, which were represented graphically and quantitatively. Young dfmr1 mutants spent excessive time grooming, with increased bout number and duration; both were rescued by transgenic wild-type dfmr1+. By two grooming-pattern measures, dfmr1-mutant flies showed elevated repetitions consistent with perseveration, which is common in FXS. In addition, the mutant flies display a preference for grooming posterior body structures, and an increased rate of grooming transitions from one site to another. We raise the possibility that courtship and circadian rhythm defects, previously reported for dfmr1 mutants, are complicated by excessive grooming. We also observed significantly increased grooming in CASK mutants, despite their dramatically decreased walking phenotype. The mutant flies, a model for human CASK-related neurodevelopmental disorders, displayed consistently elevated grooming indices throughout the assay, but transient locomotory activation immediately after placement in the arena. Based on published data identifying FMRP-target transcripts and functional analyses of mutations causing human genetic neurodevelopmental disorders, we propose the following proteins as candidate mediators of excessive repetitive behaviors in FXS: CaMKIIα, NMDA receptor subunits 2A and 2B, NLGN3, and SHANK3. Together, these fly-mutant phenotypes and mechanistic insights provide starting points for drug discovery to identify compounds that reduce dysfunctional repetitive behaviors.


Assuntos
Comportamento Animal/fisiologia , Proteínas de Drosophila/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Atividade Motora/fisiologia , Transtornos do Neurodesenvolvimento/fisiopatologia , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Drosophila melanogaster , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/fisiopatologia , Locomoção/fisiologia , Transtornos do Neurodesenvolvimento/genética , Fenótipo
2.
BMJ Open ; 9(9): e028753, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519672

RESUMO

OBJECTIVES: To quantify the economic and psychological impact of the cancellation of operations due to winter pressures on patients, their families and the economy. DESIGN: This questionnaire study was designed with the help of patient groups. Data were collected on the economic and financial burden of cancellations. Emotions were also quantified on a 5-point Likert scale. SETTING: Five NHS Hospital Trusts in the East Midlands region of England. PARTICIPANTS: We identified 796 participants who had their elective operations cancelled between 1 November 2017 and 31 March 2018 and received responses from 339 (43%) participants. INTERVENTIONS: Participants were posted a modified version of a validated quality of life questionnaire with a prepaid return envelope. MAIN OUTCOME MEASURES: The primary outcome measures were the financial and psychological impact of the cancellation of elective surgery on patients and their families. RESULTS: Of the 339 respondents, 163 (48%) were aged <65 years, with 111 (68%) being in employment. Sixty-six (19%) participants had their operations cancelled on the day. Only 69 (62%) of working adults were able to return to work during the time scheduled for their operation, with a mean loss of 5 working days (SD 10). Additional working days were lost subsequently by 60 (54%) participants (mean 7 days (SD 10)). Family members of 111 (33%) participants required additional time off work (mean 5 days (SD 7)). Over 30% of participants reported extreme levels of sadness, disappointment, anger, frustration and stress. At least moderate concern about continued symptoms was reported by 234 (70%) participants, and 193 (59%) participants reported at least moderate concern about their deteriorating condition. CONCLUSIONS: The cancellation of elective surgery during the winter had an adverse impact on patients and the economy, including days of work lost and health-related anxiety. We recommend better planning, and provision of more notice and better support to patients.


Assuntos
Agendamento de Consultas , Procedimentos Cirúrgicos Eletivos , Pacientes não Comparecentes/psicologia , Pacientes não Comparecentes/estatística & dados numéricos , Estações do Ano , Revisão da Utilização de Recursos de Saúde , Eficiência Organizacional , Inglaterra , Hospitais de Distrito , Humanos , Modelos Lineares , Salas Cirúrgicas/organização & administração , Inquéritos e Questionários , Recursos Humanos
3.
Appl Environ Microbiol ; 78(21): 7527-37, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22885757

RESUMO

High-throughput, culture-independent surveys of bacterial and archaeal communities in soil have illuminated the importance of both edaphic and biotic influences on microbial diversity, yet few studies compare the relative importance of these factors. Here, we employ multiplexed pyrosequencing of the 16S rRNA gene to examine soil- and cactus-associated rhizosphere microbial communities of the Sonoran Desert and the artificial desert biome of the Biosphere2 research facility. The results of our replicate sampling approach show that microbial communities are shaped primarily by soil characteristics associated with geographic locations, while rhizosphere associations are secondary factors. We found little difference between rhizosphere communities of the ecologically similar saguaro (Carnegiea gigantea) and cardón (Pachycereus pringlei) cacti. Both rhizosphere and soil communities were dominated by the disproportionately abundant Crenarchaeota class Thermoprotei, which comprised 18.7% of 183,320 total pyrosequencing reads from a comparatively small number (1,337 or 3.7%) of the 36,162 total operational taxonomic units (OTUs). OTUs common to both soil and rhizosphere samples comprised the bulk of raw sequence reads, suggesting that the shared community of soil and rhizosphere microbes constitute common and abundant taxa, particularly in the bacterial phyla Proteobacteria, Actinobacteria, Planctomycetes, Firmicutes, Bacteroidetes, Chloroflexi, and Acidobacteria. The vast majority of OTUs, however, were rare and unique to either soil or rhizosphere communities and differed among locations dozens of kilometers apart. Several soil properties, particularly soil pH and carbon content, were significantly correlated with community diversity measurements. Our results highlight the importance of culture-independent approaches in surveying microbial communities of extreme environments.


Assuntos
Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Cactaceae/microbiologia , Metagenoma , Microbiologia do Solo , Solo/análise , Arizona , Biodiversidade , DNA Bacteriano/genética , Clima Desértico , Geografia , Consórcios Microbianos , RNA Ribossômico 16S , Rizosfera , Análise de Sequência de DNA
4.
J Comp Neurol ; 520(15): 3446-70, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22431149

RESUMO

Copepods are a diverse and ecologically crucial group of minute crustaceans that are relatively neglected in terms of studies on nervous system organization. Recently, morphological neural characters have helped clarify evolutionary relationships within Arthropoda, particularly among Tetraconata (i.e., crustaceans and hexapods), and indicate that copepods occupy an important phylogenetic position relating to both Malacostraca and Hexapoda. This taxon therefore provides the opportunity to evaluate those neural characters common to these two clades likely to be results of shared ancestry (homology) versus convergence (homoplasy). Here we present an anatomical characterization of the brain and central nervous system of the well-studied harpacticoid copepod species Tigriopus californicus. We show that this species is endowed with a complex brain possessing a central complex comprising a protocerebral bridge and central body. Deutocerebral glomeruli are supplied by the antennular nerves, and a lateral protocerebral olfactory neuropil corresponds to the malacostracan hemiellipsoid body. Glomeruli contain synaptic specializations comparable to the presynaptic "T-bars" typical of dipterous insects, including Drosophila melanogaster. Serotonin-like immunoreactivity pervades the brain and ventral nervous system, with distinctive deutocerebral distributions. The present observations suggest that a suite of morphological characters typifying the Tigriopus brain reflect a ground pattern organization of an ancestral Tetraconata, which possessed an elaborate and structurally differentiated nervous system.


Assuntos
Evolução Biológica , Sistema Nervoso Central/anatomia & histologia , Copépodes/anatomia & histologia , Gânglios dos Invertebrados/anatomia & histologia , Filogenia , Animais , Sistema Nervoso Central/fisiologia , Copépodes/fisiologia , Gânglios dos Invertebrados/fisiologia , Terminações Pré-Sinápticas/fisiologia , Terminações Pré-Sinápticas/ultraestrutura , Neurônios Serotoninérgicos/fisiologia , Neurônios Serotoninérgicos/ultraestrutura , Especificidade da Espécie
5.
Arthropod Struct Dev ; 40(3): 289-302, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21315832

RESUMO

The enormous diversity of Arthropoda has complicated attempts by systematists to deduce the history of this group in terms of phylogenetic relationships and phenotypic change. Traditional hypotheses regarding the relationships of the major arthropod groups (Chelicerata, Myriapoda, Crustacea, and Hexapoda) focus on suites of morphological characters, whereas phylogenomics relies on large amounts of molecular sequence data to infer evolutionary relationships. The present discussion is based on expressed sequence tags (ESTs) that provide large numbers of short molecular sequences and so provide an abundant source of sequence data for phylogenetic inference. This study presents well-supported phylogenies of diverse arthropod and metazoan outgroup taxa obtained from publicly-available databases. An in-house bioinformatics pipeline has been used to compile and align conserved orthologs from each taxon for maximum likelihood inferences. This approach resolves many currently accepted hypotheses regarding internal relationships between the major groups of Arthropoda, including monophyletic Hexapoda, Tetraconata (Crustacea + Hexapoda), Myriapoda, and Chelicerata sensu lato (Pycnogonida + Euchelicerata). "Crustacea" is a paraphyletic group with some taxa more closely related to the monophyletic Hexapoda. These results support studies that have utilized more restricted EST data for phylogenetic inference, yet they differ in important regards from recently published phylogenies employing nuclear protein-coding sequences. The present results do not, however, depart from other phylogenies that resolve Branchiopoda as the crustacean sister group of Hexapoda. Like other molecular phylogenies, EST-derived phylogenies alone are unable to resolve morphological convergences or evolved reversals and thus omit what may be crucial events in the history of life. For example, molecular data are unable to resolve whether a Hexapod-Branchiopod sister relationship infers a branchiopod-like ancestry of the Hexapoda, or whether this assemblage originates from a malacostracan-like ancestor, with the morphologically simpler Branchiopoda being highly derived. Whereas this study supports many internal arthropod relationships obtained by other sources of molecular data, other approaches are required to resolve such evolutionary scenarios. The approach presented here turns out to be essential: integrating results of molecular phylogenetics and neural cladistics to infer that Branchiopoda evolved simplification from a more elaborate ancestor. Whereas the phenomenon of evolved simplification may be widespread, it is largely invisible to molecular techniques unless these are performed in conjunction with morphology-based strategies.


Assuntos
Crustáceos/classificação , Crustáceos/genética , Etiquetas de Sequências Expressas , Insetos/classificação , Insetos/genética , Animais , Sistema Nervoso Central , Sequência Conservada , Funções Verossimilhança , Filogenia
6.
Arthropod Struct Dev ; 40(3): 276-88, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21333750

RESUMO

Traditional hypotheses regarding the relationships of the major arthropod lineages focus on suites of comparable characters, often those that address features of the exoskeleton. However, because of the enormous morphological variety among arthropods, external characters may lead to ambiguities of interpretation and definition, particularly when species have undergone evolutionary simplification and reversal. Here we present the results of a cladistic analysis using morphological characters associated with brains and central nervous systems, based on the evidence that cerebral organization is generally robust over geological time. Well-resolved, strongly supported phylogenies were obtained from a neuromorphological character set representing a variety of discrete neuroanatomical traits. Phylogenetic hypotheses from this analysis support many accepted relationships, including monophyletic Chelicerata, Myriapoda, and Hexapoda, paraphyletic Crustacea and the union of Hexapoda and Crustacea (Tetraconata). They also support Mandibulata (Myriapoda + Tetraconata). One problematic result, which can be explained by symplesiomorphies that are likely to have evolved in deep time, is the inability to resolve Onychophora as a taxon distinct from Arthropoda. Crucially, neuronal cladistics supports the heterodox conclusion that both Hexapoda and Malacostraca are derived from a common ancestor that possessed a suite of discrete neural centers comprising an elaborate brain. Remipedes and copepods, both resolved as basal to Branchiopoda share a neural ground pattern with Malacostraca. These findings distinguish Hexapoda (Insecta) from Branchiopoda, which is the sister group of the clade Malacostraca + Hexapoda. The present study resolves branchiopod crustaceans as descendents of an ancestor with a complex brain, which means that they have evolved secondary simplification and the loss or reduction of numerous neural systems.


Assuntos
Sistema Nervoso Central/anatomia & histologia , Crustáceos/anatomia & histologia , Crustáceos/classificação , Insetos/anatomia & histologia , Insetos/classificação , Animais , Crustáceos/genética , Insetos/genética , Filogenia , Especificidade da Espécie
7.
J Pak Med Assoc ; 57(12): 616-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18173048

RESUMO

Primary aortoenteric fistula is a rare but potentially fatal cause of gastrointestinal bleeding. The diagnosis of primary aortoeteric fistula is difficult to make and is usually accompanied by a very high level of clinical suspicion. In the context of a known abdominal aortic aneurysm it is reasonable to have a high index of clinical suspicion ofaortoenteric fistula. It should be included in the differential diagnosis with low back pain and a palpable midline abdominal mass in a haemodynamically stable patient. We present a case of a 59 year old man with no past history of abdominal aortic aneurysm presented with lower back and periumblical pain. Initial misdiagnosis led to a delay in treatment and the patient succumbed to the illness.


Assuntos
Doenças da Aorta/diagnóstico , Fístula Intestinal/diagnóstico , Fístula Vascular/diagnóstico , Dor Abdominal/diagnóstico , Doenças da Aorta/fisiopatologia , Erros de Diagnóstico , Humanos , Fístula Intestinal/fisiopatologia , Dor Lombar/diagnóstico , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Fístula Vascular/fisiopatologia
8.
Am J Trop Med Hyg ; 75(2): 346-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16896146

RESUMO

From June 19, 2003 to August 18, 2003, we surveyed the mosquitoes of Oberlin, OH, for West Nile Virus (WNV) infection using reverse transcriptase-polymerase chain reaction. A total of 12,055 mosquitoes, representing 17 species or species groups and 4 genera, were collected in gravid traps at seven sites throughout the city, with Culex pipiens/restuans being the most abundant and showing the highest minimum infection rate (MIR) of 0.78. This represents a decrease in WNV enzootic activity from the previous year. Both Cx. pipiens/restuans abundance and MIR increased significantly with date. However, we found no correlation between Cx. pipiens/restuans abundance and MIR.


Assuntos
Culicidae/virologia , Insetos Vetores/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Culicidae/classificação , Feminino , Masculino , Ohio , Densidade Demográfica , Vigilância da População/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Tempo , Febre do Nilo Ocidental/transmissão
9.
J Med Entomol ; 43(3): 589-93, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16739420

RESUMO

From June through September 2003, we conducted a survey of female Aedes triseriatus (Say) for infection with La Crosse encephalitis virus (family Bunyaviridae, genus Orthobunyavirus, LACV) and West Nile virus (family Flaviviridae, genus Flavivirus, WNV) at three locations in Lorain County, Ohio. To determine infection rate and seasonal variation of both viruses in the Ae. triseriatus population, Ae. triseriatus were collected weekly by using gravid traps and CO2-baited CDC light traps and tested for virus by using reverse transcriptase polymerase chain reaction. In total, 170 pools comprised of 2,143 females were tested for LACV, of which seven were positive; the maximum likelihood estimate of infection rate combined throughout the season was 3.22/1,000. None of 170 pools comprised of 2,158 females tested for WNV were positive. LACV-positive pools were detected between late July and early September.


Assuntos
Aedes/virologia , Vírus La Crosse/isolamento & purificação , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Feminino , Insetos Vetores , Vírus La Crosse/genética , Ohio , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Vírus do Nilo Ocidental/genética
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