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1.
Transl Psychiatry ; 14(1): 113, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396013

RESUMO

Antipsychotic-induced low availability of group II metabotropic glutamate receptors (including mGlu2R and mGlu3R) in brains of schizophrenia patients may explain the limited efficacy of mGlu2/3R ligands in clinical trials. Studies evaluating mGlu2/3R levels in well-designed, large postmortem brain cohorts are needed to address this issue. Postmortem samples from the dorsolateral prefrontal cortex of 96 schizophrenia subjects and matched controls were collected. Toxicological analyses identified cases who were (AP+) or were not (AP-) receiving antipsychotic treatment near the time of death. Protein and mRNA levels of mGlu2R and mGlu3R, as well as GRM2 and GRM3 promoter-attached histone posttranslational modifications, were quantified. Experimental animal models were used to compare with data obtained in human tissues. Compared to matched controls, schizophrenia cortical samples had lower mGlu2R protein amounts, regardless of antipsychotic medication. Downregulation of mGlu3R was observed in AP- schizophrenia subjects only. Greater predicted occupancy values of dopamine D2 and serotonin 5HT2A receptors correlated with higher density of mGlu3R, but not mGlu2R. Clozapine treatment and maternal immune activation in rodents mimicked the mGlu2R, but not mGlu3R regulation observed in schizophrenia brains. mGlu2R and mGlu3R mRNA levels, and the epigenetic control mechanisms did not parallel the alterations at the protein level, and in some groups correlated inversely. Insufficient cortical availability of mGlu2R and mGlu3R may be associated with schizophrenia. Antipsychotic treatment may normalize mGlu3R, but not mGlu2R protein levels. A model in which epigenetic feedback mechanisms controlling mGlu3R expression are activated to counterbalance mGluR loss of function is described.


Assuntos
Antipsicóticos , Receptores de Glutamato Metabotrópico , Esquizofrenia , Animais , Humanos , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Esquizofrenia/metabolismo , Receptores de Glutamato Metabotrópico/genética , Encéfalo/metabolismo , Epigênese Genética , RNA Mensageiro/metabolismo
2.
Curr Probl Diagn Radiol ; 52(6): 522-527, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37718184

RESUMO

PURPOSE: The financial sustainability of the US healthcare system is a growing concern in an environment of declining reimbursement and rising costs. Variable Centers for Medicare and Medicaid (CMS) reimbursement and denial rates for specific imaging examinations exist across sites of service, adding complexity to financial planning for healthcare organizations. Understanding the financial implications of site of service in existing CMS reimbursement for imaging may be of strategic importance for organizations going forward. MATERIALS AND METHODS: Current Procedural Terminology (CPT) codes were obtained for common cross-sectional imaging examinations using the 2022 CMS Medicare Physician Fee Schedule. Using reimbursement rates with historical volumes and denial rates, a simulation was created to estimate the overall reimbursement of paired hospital outpatient departments (HOPD) and free-standing office (FSO) sites. A baseline simulation was performed with random allocation of imaging examinations between sites of service, and an optimized simulation was performed to estimate the maximum financial impact of targeted allocation between sites. These simulations were performed for paired CT and MR scanners separately. RESULTS: For CT, the baseline simulation estimated annual average reimbursement for combined HOPD and FSO was $3.25M. Reimbursement increased to $3.51M after optimized reallocation of studies between sites of service, resulting in an expected gain of $260,162 for a set of paired HOPD and FSO scanners. For MR, the same approach resulted in baseline reimbursement of $2.51M, increasing to $2.60M upon reallocation between sites for an expected gain of $87,532. Assuming a stable cost of service delivery, this approach would result in improved margins of 8% for CT and 3.5% for MR. There were 28 CT and 19 MRI daily patient imaging appointments at each respective HOPD and FSO scanners, unchanged between baseline and optimized cases. Differences in reimbursement rates between sites were the dominant driver of increased margins at low denial rates, although denial rates became dominant at values greater than 50%. CONCLUSION: Given CMS payment and denial rate variability, optimally allocating imaging studies between sites of service may improve reimbursement for the same services delivered. Although financial incentives exist for site allocation, such decisions should require physician input to assess safety and appropriate level of care. This work contributes to an understanding of financial incentives of existing reimbursement policy and may guide future policy design towards high value care.

3.
J Imaging ; 8(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36547491

RESUMO

Advances in Artificial intelligence (AI) and embedded systems have resulted on a recent increase in use of image processing applications for smart cities' safety. This enables a cost-adequate scale of automated video surveillance, increasing the data available and releasing human intervention. At the same time, although deep learning is a very intensive task in terms of computing resources, hardware and software improvements have emerged, allowing embedded systems to implement sophisticated machine learning algorithms at the edge. Additionally, new lightweight open-source middleware for constrained resource devices, such as EdgeX Foundry, have appeared to facilitate the collection and processing of data at sensor level, with communication capabilities to exchange data with a cloud enterprise application. The objective of this work is to show and describe the development of two Edge Smart Camera Systems for safety of Smart cities within S4AllCities H2020 project. Hence, the work presents hardware and software modules developed within the project, including a custom hardware platform specifically developed for the deployment of deep learning models based on the I.MX8 Plus from NXP, which considerably reduces processing and inference times; a custom Video Analytics Edge Computing (VAEC) system deployed on a commercial NVIDIA Jetson TX2 platform, which provides high level results on person detection processes; and an edge computing framework for the management of those two edge devices, namely Distributed Edge Computing framework, DECIoT. To verify the utility and functionality of the systems, extended experiments were performed. The results highlight their potential to provide enhanced situational awareness and demonstrate the suitability for edge machine vision applications for safety in smart cities.

4.
Innov Clin Neurosci ; 19(7-9): 55-60, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204172

RESUMO

Objective: This article reviews evidence-based psychiatric uses of gabapentin, along with associated risks. Method of Research: An extensive literature review was conducted, primarily of articles searchable in PubMed, relating to psychiatric uses, safety, and adverse effects of gabapentin. Results: Evidence supports gabapentin as a treatment for alcohol withdrawal and alcohol use disorder. There is sufficient evidence to consider gabapentin as a third-line treatment for social anxiety disorder and severe panic disorder. Evidence does not support the use of gabapentin for bipolar disorder, major depressive disorder (MDD), posttraumatic stress disorder (PTSD), obsessive compulsive disorder (OCD), stimulant use disorder, or opioid withdrawal. Risks of gabapentin use are highest among those with a history of a substance use disorder and those concurrently taking opioids. Conclusion: While gabapentin has a place in psychiatry for a select few indications, the literature does not support its use for many studied diagnoses.

5.
Mater Today Bio ; 15: 100273, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35572855

RESUMO

Epistaxis is one of the most common otorhinolaryngology emergencies worldwide. Although there are currently several treatments available, they present several disadvantages. This, in addition to the increasing social need of being environmentally respectful, led us to investigate whether a sponge-like scaffold (SP-CH) produced from natural by-products of the food industry - soy protein and ß-chitin - can be employed as a nasal pack for the treatment of epistaxis. To evaluate the potential of our material as a nasal pack, it was compared with two of the most commonly used nasal packs in the clinic: a basic gauze and the gold standard Merocel®. Our SP-CH presented great physicochemical and mechanical properties, lost weight in aqueous medium, and could even partially degrade when incubated in blood. It was shown to be both biocompatible and hemocompatible in vitro, clearing up any doubt about its safety. It showed increased blood clotting capacity in vitro, as well as increased capacity to bind both red blood cells and platelets, compared to the standard gauze and Merocel®. Finally, a rat-tail amputation model revealed that our SP-CH could even reduce bleeding time in vivo. This work, carried out from a circular economy approach, demonstrates that a green strategy can be followed to manufacture nasal packs using valorized by-products of the food industry, with equal or even better hemostatic properties than the gold standard in the clinic.

6.
Biodivers Data J ; 8: e56648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33177947

RESUMO

BACKGROUND: An important functional trait of organisms is their trophic mode. It determines their position within food webs, as well as their function within an ecosystem. For the better part of the 20th century, aquatic protist communities were thought to consist mainly of producers (phytoplankton) and consumers (protozooplankton). Phytoplankton cover their energy requirements through photosynthesis (phototrophy), while protozooplankton graze on prey and organic particles (phagotrophy). However, over the past decades, it was shown that another trophic group (mixoplankton) comprise a notable part of aquatic protist communities. Mixoplankton employ a third trophic mode by combining phototrophy and phagotrophy (mixotrophy). Due to the historical dichotomy, it is not straightforward to gain adequate and correct information on the trophic mode of aquatic protists. Long hours of literature research or expert knowledge are needed to correctly assign trophic modes. Additionally, aquatic protists also have a long history of undergoing taxonomic changes which make it difficult to compare past and present literature. While WoRMS, the World Register of Marine Species, keeps track of the taxonomic changes and assigns each species a unique AphiaID that can be linked to its various historic and present taxonomic hierarchy, there is currently no machine-readable database to query aquatic protists for their trophic modes. NEW INFORMATION: This paper describes a dataset that was submitted to WoRMS and links aquatic protist taxa, with a focus on marine taxa, to their AphiaID and their trophic mode. The bulk of the data used for this dataset stems from (routine) monitoring stations in the North Sea and the Baltic Sea. The data were augmented and checked against state-of-the-art knowledge on mixoplankton taxa by consulting literature and experts. Thus, this dataset provides a first attempt to make the trophic mode of aquatic protists easily accessible in both a human- and machine-readable format.

7.
Sensors (Basel) ; 19(1)2018 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-30585212

RESUMO

The design and operation of manufacturing systems is evolving to adapt to different challenges. One of the most important is the reconfiguration of the manufacturing process in response to context changes (e.g., faulty equipment or urgent orders, among others). In this sense, the Autonomous Transport Vehicle (ATV) plays a key role in building more flexible and decentralized manufacturing systems. Nowadays, robotic frameworks (RFs) are used for developing robotic systems such as ATVs, but they focus on the control of the robotic system itself. However, social abilities are required for performing intelligent interaction (peer-to-peer negotiation and decision-making) among the different and heterogeneous Cyber Physical Production Systems (such as machines, transport systems and other equipment present in the factory) to achieve manufacturing reconfiguration. This work contributes a generic multi-layer architecture that integrates a RF with a Multi-Agent System (MAS) to provide social abilities to ATVs. This architecture has been implemented on ROS and JADE, the most widespread RF and MAS framework, respectively. We believe this to be the first work that addresses the intelligent interaction of transportation systems for flexible manufacturing environments in a holistic form.

8.
Zootaxa ; 4402(2): 251-282, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29690266

RESUMO

The whitefly genus Tuberaleyrodes Takahashi is reviewed using types and determined specimens. The generic diagnosis is redefined together with description of five new species: T. bruneiensis Dubey Martin sp. nov. from Brunei, T. crypta Dubey Martin sp. nov. from Hong Kong, and T. ordo Dubey Martin sp. nov., T. aequalis Dubey Martin sp. nov. and T. variabilis Dubey Martin sp. nov. from Malaysia. New species descriptions are accompanied with camera lucida drawings and microphotographs of holotype and paratypes. Tuberaleyrodes actinodaphnis Takahashi is elevated from its status as a variety of T. machili Takahashi to species level. Lectotypes are selected for T. actinodaphnis Takahashi Stat. nov. and T. bobuae Takahashi. Tuberaleyrodes actinodaphnis Takahashi is a new record to Taiwan. A new combination, Tuberaleyrodes glutae (Corbett) Comb. nov. is proposed for Dialeurodes glutae Corbett. Two species, T. glutae (Corbett) and Tuberaleyrodes spiniferosa (Corbett) are re-described, and placement of T. spiniferosa in the genus Tuberaleyrodes is confirmed. The genus Tuberaleyrodes is newly recorded from Borneo and Sulawesi. An identification key to puparia of Tuberaleyrodes species so far described is provided along with the countries of present records. Four plants families viz., Annonaceae, Fabaceae, Myristicaceae and Pentaphylacaeae are recorded as new hosts for Tuberaleyrodes species. New host plant records are indicated.


Assuntos
Hemípteros , Animais , Bornéu , Brunei , Hong Kong , Indonésia , Malásia , Taiwan
9.
Zootaxa ; 4358(2): 295-310, 2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29245470

RESUMO

The adult female, first-instar nymph, second-instar male, third-instar female, pupa and adult male of a new species of Marsipococcus Cockerell & Bueker (Hemiptera: Coccomorpha: Coccidae) from Malaysia, M. ulubendulensis Lagowska & Martin sp. n., are described and illustrated, while the second-instar female is only described. Marsipococcus is rediagnosed and a key to the adult females of the four species now placed in this genus is included.


Assuntos
Hemípteros , Animais , Feminino , Malásia , Masculino , Ninfa , Pupa
10.
Zootaxa ; 4158(4): 491-506, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27615899

RESUMO

The immature stages are described for the first time for Chironomus (Xenochironomus) australiensis Freeman (Diptera: Chironomidae) and the adult male is redescribed including from type specimens. The species does not belong to Chironomus Meigen or Xenochironomus Kieffer, but is best placed in a modestly expanded Einfeldia Kieffer. Application of this genus name is clarified, including by a lectotype fixation for its type species, E. pectoralis Kieffer, 1924. Einfeldia australiensis (Freeman) comb. n. provides the first record of the genus from Australia; otherwise the genus is reported confidently only from North America, Central America and western Europe to Japan. The immature stages of E. australiensis occur in relatively shallow mesotrophic to eutrophic dune lakes and maars with circum-neutral pH and high conductivity, from southeastern Queensland to southern Australia. The cytology is described briefly from larval salivary glands. Alternative genus placements for the species are discussed, and problems with Einfeldia and connected systematics in the tribe Chironomini are addressed.


Assuntos
Chironomidae/classificação , Chironomidae/crescimento & desenvolvimento , América , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Austrália , Tamanho Corporal , Chironomidae/anatomia & histologia , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Pupa/anatomia & histologia , Pupa/classificação , Pupa/crescimento & desenvolvimento
11.
Zootaxa ; 4079(4): 429-47, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27394199

RESUMO

Polypedilum nubifer (Skuse, 1889), originally described from Australia, is an apparently widespread species of Chironomidae (Diptera) that can attain nuisance densities in some eutrophic water bodies. Appropriate management depends upon the identity and ability to distinguish from potential cryptic taxa. A morphological study of larvae, pupae and adults of both sexes confirmed P. nubifer as widely distributed and frequently abundant, but also revealed two previously cryptic species of limited distribution in northern Australia. These species are described as new and illustrated in all stages here. Polypedilum quasinubifer Cranston sp. n. is described from north-west Queensland, Australia and also from Thailand and Singapore. Polypedilum paranubifer Cranston sp. n. is known only from retention ponds of a uranium mine in Northern Territory, Australia. Unusual morphological features of P. nubifer including alternate Lauterborn organs on the larval antenna, cephalic tubules on the pupa and frontal tubercles on the adult head are present in both new species as well. Newly slide-mounted types of Polypedilum pelostolum Kieffer, 1912 (lectotype designated here) confirm synonymy to Chironomus nubifer Skuse, 1889, examined also as newly-slide mounted types. Reviewed plus new evidence does not support recognition of Tripedilum Kieffer, 1921 as a separate taxon; therefore, Tripedilum is returned to junior synonymy with Polypedilum s. str.


Assuntos
Chironomidae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Austrália , Tamanho Corporal , Chironomidae/anatomia & histologia , Chironomidae/crescimento & desenvolvimento , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Pupa/anatomia & histologia , Pupa/classificação , Pupa/crescimento & desenvolvimento , Singapura , Tailândia
12.
Zootaxa ; 4072(1): 39-60, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-27395909

RESUMO

Chironomidae are a highly diverse group of insects. Members of this family are often included in programs monitoring the health of freshwater ecosystems. However, a difficulty in morphological identification, particularly of larval stages is the major obstacle to this application. In this study, we tested the efficiency of mitochondrial cytochrome c oxidase I (COI) sequences as the DNA barcoding region for species identification of Chironomidae in Thailand. The results revealed 14 species with a high success rate (>90%) for the correct species identification, which suggests the potential usefulness of the technique. However, some morphological species possess high (>3%) intraspecific genetic divergence that suggests these species could be species complexes and need further morphological or cytological examination. Sequence-based species delimitation analyses indicated that most specimens identified as Chironomus kiiensis, Tokunaga 1936, in Japan are conspecific with C. striatipennis, Kieffer 1912, although a small number form a separate cluster. A review of the descriptions of Kiefferulus tainanus (Kieffer 1912) and its junior synonym, K. biroi (Kieffer 1918), following our results, suggests that this synonymy is probably not correct and that K. tainanus occurs in Japan, China and Singapore, while K. biroi occurs in India and Thailand. Our results therefore revealed the usefulness of DNA barcoding for correct species identification of Chironomidae, particularly the immature stages. In addition, DNA barcodes could also uncover hidden diversity that can guide further taxonomic study, and offer a more efficient way to identify species than morphological analysis where large numbers of specimens are involved, provided the identifications of DNA barcodes in the databases are correct. Our studies indicate that this is not the case, and we identify cases of misidentifications for C. flaviplumus, Tokunaga 1940 and K. tainanus.


Assuntos
Chironomidae/classificação , Chironomidae/genética , Código de Barras de DNA Taxonômico , Animais , Larva , Masculino , Tailândia
13.
Zootaxa ; 4006(1): 128-42, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26623761

RESUMO

All life stages (adult female and male, first-instar nymph, second-instar male and female nymphs, and prepupa and pupa) of a new species of Asterolecaniidae, Bambusaspis transversa Lagowska & Martin sp. n., from bamboo in Malaysia, are described and illustrated. The adult female and first-instar nymphs are compared with those Bambusaspis species considered to be closest to the new species.


Assuntos
Hemípteros/anatomia & histologia , Hemípteros/classificação , Animais , Bambusa/parasitologia , Feminino , Hemípteros/crescimento & desenvolvimento , Malásia , Masculino , Ninfa/anatomia & histologia , Especificidade da Espécie
14.
Zootaxa ; 3881(1): 33-48, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25543618

RESUMO

The genus Acanthaleyrodes Takahashi is reported for the first time from India. Acanthaleyrodes elevatus sp. n. is described from Bridelia retusa in Kerala, India, with a key to puparia of Acanthaleydes species. The new species differs in its exceptionally elevated eighth abdominal tergite, circular vasiform orifice and eight pairs of subdorsal setae. The generic characteristics of Acanthaleyrodes are redefined and distinguished from those of Tuberaleyrodes Takahashi. A. styraci Takahashi is re-described in detail with illustrations of puparia and immatures from Hong Kong. A lectotype puparium is designated for A. callicarpae Takahashi. The development of tuberculate setae is discussed, in whitefly puparia and earlier nymphal instars, and considered to be subject to environmental modification.


Assuntos
Hemípteros/anatomia & histologia , Hemípteros/classificação , Sensilas/anatomia & histologia , Distribuição Animal , Animais , Feminino , Índia , Masculino , Pupa/anatomia & histologia , Pupa/classificação , Especificidade da Espécie
15.
Nucl Med Commun ; 35(12): 1197-203, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25211626

RESUMO

BACKGROUND: PET with computed tomography (PET-CT) is an important imaging modality in the assessment of patients with cancer. The glucose analogue fluorine-18 2'-fluorodeoxyglucose (F-FDG) is a commonly used tracer in PET-CT. As we serve a diverse population with a high prevalence of diabetes mellitus (DM) and malignant disease, we wished to ensure that patients had access to the PET-CT imaging service as efficiently as possible. PATIENTS AND METHODS: We reviewed the simple instructions followed by patients and technical staff in preparation for F-FDG PET-CT scanning at our institution to ensure that there was minimum disruption to the diagnostic pathway. RESULTS: Only a small percentage (1.5%, 3/200) of patients referred for PET-CT could not proceed with scanning because of unacceptably high serum glucose (SG) levels at the first attendance (SG≥11.1 mmol/l), all of whom were successfully scanned within a week. This cutoff level of SG is based on the European Association of Nuclear Medicine (EANM) guidelines. There was no case in which the patient's diagnostic pathway was delayed purely by the time taken to control glycaemic levels. A significant number of patients were in fact diagnosed with DM, impaired glucose tolerance or impaired fasting glucose as a result of being referred for the PET-CT scan. These patients were actually those for whom a diagnosis of DM was thought to be absent at the time of referral, as opposed to those for whom the diagnosis was not known one way or the other. CONCLUSIONS: We conclude that scheduling for F-FDG PET-CT can be performed efficiently using simple preparation instructions, even in the context of high prevalence of DM and with a high rate of incidental diagnosis of DM at the time of scanning.


Assuntos
Diabetes Mellitus/diagnóstico por imagem , Fluordesoxiglucose F18 , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Diabetes Mellitus/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Zookeys ; (425): 113-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25147453

RESUMO

Two new species of Aphidura Hille Ris Lambers, 1956 (Hemiptera, Aphididae, Macrosiphini) are described; Aphidura libanensis sp. n. from Prunus prostrata in Lebanon, and Aphidura corsicensis sp. n. from Cerastium soleirolii in Corsica (France). Studies of Aphidura bozhkoae specimens from different localities have revealed that this species varies in its pattern of dorsal sclerotisation and other morphological characters, within and between populations. An updated key for identifying the world's species of Aphidura is presented.

17.
Zootaxa ; (3811): 316-24, 2014 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-24943169

RESUMO

The polytene chromosomes of three North American species in the subgenus Chaetolabis of the genus Chironomus are described and compared to the published karyotypes of two Palearctic species. Chironomus (Chaetolabis) atroviridis has four polytene chromosomes, like the Palearctic C. globulus, while C. ochreatus and the North American populations of C. bitumineus each have three chromosomes due to tandem fusion of arm G to arm E, as in the Palearctic populations of C. bitumineus. The results support the existence of distinct species, particularly clarifying that the names C. atroviridis, C. bitumineus and C. ochreatus cannot be synonyms, as was suggested by some previous workers. The question of whether Lobochironomus "sp. Ya6" might be conspecific with C. macani is also discussed.


Assuntos
Chironomidae , Cromossomos de Insetos/genética , Animais , Chironomidae/classificação , Chironomidae/genética , Genes de Insetos , Cariótipo , Masculino
18.
Zootaxa ; 3741: 401-58, 2013 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-25113001

RESUMO

Chironomus Meigen (Diptera, Chironomidae) larvae are usually the largest sediment-burrowing chironomids, and as such often constitute a major part of the freshwater infaunal biomass. However, use of this genus in ecological, environmental and paleoecological studies is hampered by the fact that Chironomus larvae are difficult to identify to species because the larvae of many species are morphologically similar. We used a combination of morphological, cytological and genetic techniques to distinguish Chironomus larvae collected from 31 water bodies located in eastern Canada, producing 17 distinguishable groupings. These groups of larvae were ultimately identified as belonging to 14 known species (C. anthracinus, C. bifurcatus, C. cucini, C. decorus-group sp. 2, C. dilutus, C. entis, C. frommeri, C. harpi, C. maturus, C. nr. atroviridis (sp. 2i), C. ochreatus, C. plumosus, C. staegeri and C. 'tigris') and three other species that remain unidentified (C. sp. NAI-III). No single approach served to delimit and identify larvae of all 17 Chironomus species that we collected. Although we expected that morphological criteria alone would be insufficient, our results suggest that DNA barcoding, using either the mitochondrial cox1 or the nuclear gb2ß gene, was also inadequate for separating some Chironomus species. Thus we suggest that multiple approaches will often be needed to correctly identify Chironomus larvae to species.


Assuntos
Chironomidae/classificação , Animais , Sequência de Bases , Canadá , Chironomidae/anatomia & histologia , Chironomidae/genética , Ciclo-Oxigenase 1/genética , Código de Barras de DNA Taxonômico , Primers do DNA/genética , Globinas/genética , Proteínas de Insetos/genética , Lagos , Larva , Proteínas Mitocondriais/genética , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA
19.
Comp Cytogenet ; 5(4): 315-28, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24260638

RESUMO

Micropsectra sedna (Oliver, 1976) is a parthenogenetic midge from the Canadian Arctic. The parthenogenetic mechanism is apomictic thelytoky, with a restitutional division during oogenesis, as found in other parthenogenetic Chironomidae. It is triploid, with two similar chromosome sets, and the third is relatively dissimilar, pairing little with the diploid set. Two karyotypes were observed: a single individual with eight polytene elements in the salivary glands (3n=12), considered standard, while the majority of larvae showed only seven polytene chromosomes (3n=11). Hybrid speciation is considered likely, although chromosomal recombination following the origin of thelytoky has played some part in karyotype evolution. A single morphologically distinct larva was also found, which might be the donor of the haploid chromosome set. The apomictic restitutional system is compared to that of the other, independently derived, parthenogenetic Chironomids to assess the extent of similarity between species.

20.
PLoS Genet ; 6(6): e1000998, 2010 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-20585622

RESUMO

The increased transcription of the Cyp6g1 gene of Drosophila melanogaster, and consequent resistance to insecticides such as DDT, is a widely cited example of adaptation mediated by cis-regulatory change. A fragment of an Accord transposable element inserted upstream of the Cyp6g1 gene is causally associated with resistance and has spread to high frequencies in populations around the world since the 1940s. Here we report the existence of a natural allelic series at this locus of D. melanogaster, involving copy number variation of Cyp6g1, and two additional transposable element insertions (a P and an HMS-Beagle). We provide evidence that this genetic variation underpins phenotypic variation, as the more derived the allele, the greater the level of DDT resistance. Tracking the spatial and temporal patterns of allele frequency changes indicates that the multiple steps of the allelic series are adaptive. Further, a DDT association study shows that the most resistant allele, Cyp6g1-[BP], is greatly enriched in the top 5% of the phenotypic distribution and accounts for approximately 16% of the underlying phenotypic variation in resistance to DDT. In contrast, copy number variation for another candidate resistance gene, Cyp12d1, is not associated with resistance. Thus the Cyp6g1 locus is a major contributor to DDT resistance in field populations, and evolution at this locus features multiple adaptive steps occurring in rapid succession.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Variações do Número de Cópias de DNA , Elementos de DNA Transponíveis , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Adaptação Biológica , Alelos , Animais , Animais Geneticamente Modificados , Loci Gênicos , Transcrição Gênica
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