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1.
Phys Rev Lett ; 132(26): 263602, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38996281

RESUMO

Solid-state spin qubits are promising candidates for quantum information processing, but controlled interactions and entanglement in large, multiqubit systems are currently difficult to achieve. We describe a method for programmable control of multiqubit spin systems, in which individual nitrogen-vacancy (NV) centers in diamond nanopillars are coupled to magnetically functionalized silicon nitride mechanical resonators in a scanning probe configuration. Qubits can be entangled via interactions with nanomechanical resonators while programmable connectivity is realized via mechanical transport of qubits in nanopillars. To demonstrate the feasibility of this approach, we characterize both the mechanical properties and the magnetic field gradients around the micromagnet placed on the nanobeam resonator. We demonstrate coherent manipulation of a spin qubit in the proximity of a transported micromagnet by utilizing nuclear spin memory and use the NV center to detect the time-varying magnetic field from the oscillating micromagnet, extracting a spin-mechanical coupling of 7.7(9) Hz. With realistic improvements, the high-cooperativity regime can be reached, offering a new avenue toward scalable quantum information processing with spin qubits.

2.
Phys Rev Lett ; 124(16): 163604, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32383959

RESUMO

We demonstrate a new mechanical transduction platform for individual spin qubits. In our approach, single micromagnets are trapped using a type-II superconductor in proximity of spin qubits, enabling direct magnetic coupling between the two systems. Controlling the distance between the magnet and the superconductor during cooldown, we demonstrate three-dimensional trapping with quality factors around 1×10^{6} and kHz trapping frequencies. We further exploit the large magnetic moment to mass ratio of this mechanical oscillator to couple its motion to the spin degrees of freedom of an individual nitrogen vacancy center in diamond. Our approach provides a new path towards interfacing individual spin qubits with mechanical motion for testing quantum mechanics with mesoscopic objects, realization of quantum networks, and ultrasensitive metrology.

3.
J Fish Biol ; 92(4): 1090-1109, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29479689

RESUMO

Headwater-resident fishes may be prone to a high rate of isolation and a pronounced hierarchical genetic structure due to a combination of niche preference and dendritic effects of river networks. Genetic isolation patterns were compared using microsatellites in six headwater fishes, Fundulus olivaceus, Semotilus atromaculatus, Erimyzon claviformis, Etheostoma artesiae, Etheostoma whipplei and Etheostoma parvipinne, in three geographic regions that included drainages of small, medium and large sizes in the southern United States. All species showed hierarchical nesting of genetic populations and there were clear and mostly consistent differences between species and regions that were identified through summary statistics derived from two independent analyses. For species comparisons, a high isolation grouping (increased number of isolated genetic clusters or sites within regions) and a low-isolation grouping (decreased number of clusters or sites) were identified. Species group placement was related to niche breadth along the river continuum and presumed abundance and variability of preferred microhabitats, with increased headwater specialization among species being associated with placement in the high-isolation grouping. There was a weakly significant positive effect of drainage size on the number of isolated clusters or sites across all species. Regional patterns were shared in two species, with the region containing the smallest drainages having lower rates of isolation in both datasets. This study shows the effects of regional and species characteristics on genetic isolation for headwater species, which are especially prone to isolation due to spatial, dendritic effects of river networks.


Assuntos
Fundulidae/genética , Genética Populacional , Percas/genética , Isolamento Reprodutivo , Animais , Ecossistema , Geografia , Repetições de Microssatélites , Rios , Estados Unidos
4.
J Immunoassay Immunochem ; 38(6): 579-594, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28699839

RESUMO

INTRODUCTION: The pharmacotherapy of pediatric patients suffering from heart failure is extrapolated from adults due to missing data in children. OBJECTIVES: Development and validation of a low-volume immunoassay for the reliable determination of renin. EXPERIMENTAL: The immunoassay was validated according to international guidelines. RESULTS: The assay allows the reliable determination of renin in 40 µL plasma within a calibration range of 4-128 pg/mL. Between-run accuracy varied from -3.3 to +3.0% (relative error), while between-run precision ranged from 4.9 to 11.3% (coefficient of variation). CONCLUSION: The low-volume immunoassay facilitates the reliable collection of pharmacodynamic data in children.


Assuntos
Imunoensaio/normas , Pediatria/métodos , Renina/sangue , Adulto , Criança , Feminino , Voluntários Saudáveis , Humanos
5.
Reprod Domest Anim ; 52(3): 397-402, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28066955

RESUMO

To achieve a standardized number of spermatozoa in the final AI dose, varying amounts of extender fluid with a fixed concentration of antimicrobial substances are currently added to boar ejaculates. This practice ignores the different degrees of dilution of the antimicrobials in the end product. In calculating the final concentration of gentamicin in AI doses from 27,538 processed boar ejaculates, we demonstrated varying gentamicin concentrations in the resultant extended boar semen samples. The median concentration was 220.37 mg/L. In 25 of the samples (0.09%), the gentamicin concentration fell below 5 mg/L, which is close to or below the epidemiological cut-off value for many bacteria. We calculated the minimum inhibitory concentration of gentamicin for bacteria isolated from raw and extended ejaculates. Five of the isolates from extended ejaculates exceeded the maximum test concentration of 512 mg/L. As a result, we are presenting an alternative method of boar semen preservation whereby a particular combination of gentamicin concentrate and antibiotic-free extender is incorporated that standardizes the antibiotic concentration in the diluted semen. The addition of standardized antibiotic concentrations did not negatively affect sperm quality when compared to the use of ready-to-use extenders. In conclusion, an end volume-based and standardized addition of gentamicin to boar ejaculates can be a helpful alternative to prevent insufficient dosage of antibiotics in liquid preserved boar semen without affecting semen quality.


Assuntos
Antibacterianos/farmacologia , Gentamicinas/farmacologia , Preservação do Sêmen/veterinária , Suínos , Animais , Antibacterianos/administração & dosagem , Relação Dose-Resposta a Droga , Gentamicinas/administração & dosagem , Masculino , Sêmen/microbiologia , Preservação do Sêmen/métodos
6.
Genes Immun ; 17(2): 79-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26673963

RESUMO

Roquin-1 (Rc3h1) is an E3 ubiquitin ligase originally discovered in a mutational screen for genetic factors contributory to systemic lupus erythematosus-like symptoms in mice. A single base-pair mutation in the Rc3h1 gene resulted in the manifestation of autoantibody production and sustained immunological inflammation characterized by excessive T follicular helper cell activation and formation of germinal centers. Subsequent studies have uncovered a multifactorial process by which Roquin-1 contributes to the maintenance of immune homeostasis. Through its interactions with partner proteins, Roquin-1 targets mRNAs for decay with inducible costimulator being a primary target. In this review, we discuss newly discovered functions of Roquin-1 in the immune system and inflammation, and in disease manifestation, and discuss avenues of further research. A model is presented for the role of Roquin in health and disease.


Assuntos
Autoanticorpos/biossíntese , Homeostase/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/genética , Lúpus Eritematoso Sistêmico/genética , Proteínas de Ligação a RNA/genética , Ubiquitina-Proteína Ligases/genética , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Centro Germinativo/imunologia , Centro Germinativo/patologia , Homeostase/genética , Humanos , Imunidade Inata , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Ativação Linfocitária , Camundongos , Mutação , Proteínas de Ligação a RNA/imunologia , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/imunologia , Transdução de Sinais , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/patologia , Ubiquitina-Proteína Ligases/imunologia
7.
Phys Rev Lett ; 116(10): 106802, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-27015502

RESUMO

Using inelastic electron scattering in combination with dielectric theory simulations on differently prepared graphene layers on silicon carbide, we demonstrate that the coupling between the 2D plasmon of graphene and the surface optical phonon of the substrate cannot be quenched by modification of the interface via intercalation. The intercalation rather provides additional modes like, e.g., the silicon-hydrogen stretch mode in the case of hydrogen intercalation or the silicon-oxygen vibrations for water intercalation that couple to the 2D plasmons of graphene. Furthermore, in the case of bilayer graphene with broken inversion symmetry due to charge imbalance between the layers, we observe a similar coupling of the 2D plasmon to an internal infrared-active mode, the LO phonon mode. The coupling of graphene plasmons to vibrational modes of the substrate surface and internal infrared active modes is envisioned to provide an excellent tool for tailoring the plasmon band structure of monolayer and bilayer graphene for plasmonic devices such as plasmon filters or plasmonic waveguides. The rigidity of the effect furthermore suggests that it may be of importance for other 2D materials as well.

8.
Chemistry ; 21(39): 13696-702, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26264355

RESUMO

Ion-like ethylzinc(II) compounds with weakly coordinating aluminates [Al(OR(F))4](-) and [(R(F)O)3Al-F-Al(OR(F))3](-) (R(F)=C(CF3)3) were synthesized in a one-pot reaction and fully characterized by single-crystal X-ray diffraction, NMR and vibrational spectroscopy, and by quantum chemical calculations. The catalytic activity of ion-like Et-Zn[Al(OR(F))4] in intermolecular hydroamination and in the unusual double hydroamination of anilines and alkynes was investigated. Favorable performance was also found in comparison to the Et2Zn/[PhNMe2H](+)[B(C6F5)4](-) system generated in situ at lower catalyst loadings of 2.5 mol %.

9.
Eur J Neurol ; 22(11): 1429-35, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26204918

RESUMO

Myofibrillar myopathies are a genetically diverse group of skeletal muscle disorders, with distinctive muscle histopathology. Causative mutations have been identified in the genes MYOT, LDB3, DES, CRYAB, FLNC, BAG3, DNAJB6, FHL1, PLEC and TTN, which encode proteins which either reside in the Z-disc or associate with the Z-disc. Mitochondrial abnormalities have been described in muscle from patients with a myofibrillar myopathy. We reviewed the literature to determine the extent of mitochondrial dysfunction in each of the myofibrillar myopathy subtypes. Abnormal mitochondrial distribution is a frequent finding in each of the subtypes, but a high frequency of COX-negative or ragged red fibres, a characteristic finding in some of the conventional mitochondrial myopathies, is a rare finding. Few in vitro studies of mitochondrial function have been performed in affected patients.


Assuntos
Mitocôndrias/patologia , Humanos , Miopatias Congênitas Estruturais/classificação , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/patologia
10.
Prev Sci ; 15(4): 557-69, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23609793

RESUMO

Representative surveys indicate that eating disorders are an increasing problem, especially among (pre)adolescents. We assessed the effects of a German school-based primary prevention program ("Torera") for seventh graders. Torera especially relates to pathological eating behavior in the realm of bulimia nervosa or binge eating disorder. The program is built upon two previously evaluated modules for sixth graders with a gender-specific adaption. The coeducational intervention involves nine manual-guided lessons touching a wide range of eating-related problems. Twenty-two Thuringian secondary schools (n = 256 boys and 277 girls, aged 11-13 years at baseline) participated in a trial with 2 control groups (untreated and pretreated) with pre-post assessment. Primary outcomes were conspicuous eating behavior and body self-esteem, measured by standardized questionnaires (SCOFF, EAT-26D, and FBeK). Girls and students at risk showed significant improvement with small (d = 0.35) to medium (d = 0.66) effect sizes on eating behavior, significantly mediated by body self-esteem. Boys only improved with respect to eating attitudes, revealing a small effect size (d = 0.35). With relatively low implementation costs (about 2.50 per student), Torera provides an efficient model for reducing risky eating behavior and strengthening body self-esteem without negative side effects. To improve the effectiveness of the intervention, further research efforts focusing on at-risk groups (secondary prevention) and structural actions for prevention (e.g., offering healthy school catering) are needed.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Comportamento de Redução do Risco , Adolescente , Atitude Frente a Saúde , Criança , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Alemanha , Humanos , Masculino
11.
J Fish Biol ; 85(5): 1726-32, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25123486

RESUMO

A total of 17 polymorphic microsatellite loci were isolated from the blackstripe topminnow Fundulus notatus. In a sample of 29 individuals, these loci were found to possess two to 19 alleles with expected heterozygosity values ranging from 0.212 to 0.919 and all but one of the loci conformed to Hardy-Weinberg equilibrium expectations. Many of these loci were polymorphic in the closely related species Fundulus olivaceus and Fundulus euryzonus providing a set of markers that should prove useful in future ecological and evolutionary studies of members of this species complex.


Assuntos
Cyprinidae/genética , Repetições de Microssatélites , Alelos , Animais , Loci Gênicos , Análise de Sequência de DNA
12.
Internist (Berl) ; 55(5): 601-6, 2014 May.
Artigo em Alemão | MEDLINE | ID: mdl-24770979

RESUMO

Guidelines for the reduction of cholesterol to prevent atherosclerotic vascular events were recently released by the American Heart Association and the American College of Cardiology. The authors claim to refer entirely to evidence from randomized controlled trials, thereby confining their guidelines to statins as the primary therapeutic option. The guidelines derived from these trials do not specify treatment goals, but refer to the percentage of cholesterol reduction by statin medication with low, moderate, and high intensity. However, these targets are just as little tested in randomized trials as are the cholesterol goals derived from clinical experience. The same applies to the guidelines of the four patient groups which are defined by vascular risk. No major statin trial has included patients on the basis of their global risk; thus the allocation criteria are also arbitrarily chosen. These would actually lead to a significant increase in the number of patients to be treated with high or maximum dosages of statins. Also, adhering to dosage regulations instead of cholesterol goals contradicts the principles of individualized patient care. The option of the new risk score to calculate lifetime risk up to the age of 80 years in addition to the 10-year risk can be appreciated. Unfortunately it is not considered in the therapeutic recommendations provided, despite evidence from population and genetic studies showing that even a moderate lifetime reduction of low-density lipoprotein (LDL) cholesterol or non-HDL cholesterol has a much stronger effect than an aggressive treatment at an advanced age. In respect to secondary prevention, the new American guidelines broadly match the European guidelines. Thus, the involved societies from Germany, Austria and Switzerland recommend continuing according to established standards, such as the EAS/ESC guidelines.


Assuntos
Anticolesterolemiantes/administração & dosagem , Aterosclerose/sangue , Aterosclerose/prevenção & controle , Dietoterapia/normas , Hipercolesterolemia/sangue , Hipercolesterolemia/prevenção & controle , Guias de Prática Clínica como Assunto , Áustria , Cardiologia/normas , Humanos , Fatores de Risco , Suíça
13.
Eur J Neurol ; 20(7): 997-1005, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23627674

RESUMO

BACKGROUND: Myalgia, defined as any pain perceived in muscle, is very common in the general population and a frequent cause for referral to neurologists, rheumatologists and internists in general. It is however only rarely due to primary muscle disease and often referred from ligaments, joints, bones, the peripheral and central nervous system. A muscle biopsy should only be performed if this is likely to be diagnostically useful. At present no 'guidelines' exist. METHODS: An EFNS panel of muscle specialists was set to review relevant studies from PubMed dating as far back as 1/1/1990. Only Class IV studies were available and therefore the recommendations arrived at are 'best practice recommendations' based on information harvested from the literature search and expert opinion. RESULTS: Muscle cramps should be recognized while drugs, infections, metabolic/ endocrinological and rheumatological causes of myalgia should be identified from the history and examination and pertinent laboratory tests. A muscle biopsy is more likely to be diagnostically useful if myalgia is exertional and if one or more of the following apply: i) there is myoglobinuria, (ii) there is a second wind phenomenon, (iii) there is muscle weakness, (iv) there is muscle hypertrophy /atrophy, (v) there is hyperCKemia (>2-3× normal), and (vi) there is a myopathic EMG. CONCLUSIONS: Patients presenting with myalgia can be recommended to have a biopsy based on careful history and examination and on simple laboratory screening.


Assuntos
Biópsia/normas , Mialgia/diagnóstico , Exercício Físico/fisiologia , Humanos , Mialgia/etiologia , Mialgia/fisiopatologia , Valor Preditivo dos Testes
14.
Neuropediatrics ; 43(6): 339-45, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23129438

RESUMO

INTRODUCTION: A total of 83% of children report headache during a 6-month period. The estimated 1-year prevalence of chronic daily headache (CDH) in children is at least 1 to 2%. Muscle pain is associated with headache severity and chronicity. Muscle pain can be associated with active muscular trigger points, a functional concept still remaining a controversy. An integrated approach including bio-behavioral management is accepted as standard treatment but does not provide sufficient pain relief in all patients. OBJECTIVE: We report the individual clinical course of five adolescents with treatment-refractory CDH associated with focal muscle pain. We describe a concept of short-term integrative intervention including botulinum toxin (StiBo) in a personalized "follow the referred pain pattern" injection regimen with the focus on long-term follow-up. RESULTS: StiBo showed short-term efficacy on headache frequency and severity. In the long-term follow-up, CDH was not existent in any of the patients. CONCLUSION: The treatment may have enabled the patients to draw attention away from a repeated circle of muscle-triggered pain and withdrawal of daily activities toward self-driven activities, thereby potentially preventing the development of further chronification. To prove this hypothesis, a prospective, placebo-controlled study in young adolescents with CDH should be initiated including objective outcome parameters on muscular level.


Assuntos
Toxinas Botulínicas/uso terapêutico , Transtornos da Cefaleia/tratamento farmacológico , Dor Musculoesquelética/tratamento farmacológico , Adolescente , Criança , Seguimentos , Transtornos da Cefaleia/complicações , Humanos , Dor Musculoesquelética/complicações , Medição da Dor , Índice de Gravidade de Doença , Resultado do Tratamento
15.
Herz ; 37(1): 51-5, 2012 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-22258137

RESUMO

The risk for myocardial infarction can be reduced by almost 50% solely by lowering LDL cholesterol. Despite success reducing LDL and cholesterol, atherosclerosis and myocardial infarction remain significant challenges. However, mechanisms of the reverse cholesterol transport system might be used more effectively in the foreseeable future. Although the benefit of high HDL cholesterol appears to be obvious, most clinical trials aimed at increasing HDL cholesterol failed to generate convincing results. Therefore, the question arises as to whether indeed only HDL level or perhaps rather more HDL function is of considerable therapeutic relevance. If function is the crucial issue drugs such as CETP (cholesteryl ester transfer protein) activators or SR-B1 (scavenger receptor type B-1) upregulators could be beneficial. These types of drugs could improve HDL metabolism and might have beneficial effects despite the fact that they lower HDL levels. Ongoing studies on next generation CETP inhibitors and nicotinic acid will clarify this question and might help in our struggle against atherosclerosis.


Assuntos
Aterosclerose/prevenção & controle , HDL-Colesterol/sangue , Infarto do Miocárdio/prevenção & controle , Anticolesterolemiantes/efeitos adversos , Anticolesterolemiantes/uso terapêutico , Aterosclerose/sangue , Atorvastatina , Proteínas de Transferência de Ésteres de Colesterol/agonistas , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Proteínas de Transferência de Ésteres de Colesterol/fisiologia , LDL-Colesterol/sangue , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Término Precoce de Ensaios Clínicos , Feminino , Fluorbenzenos/efeitos adversos , Fluorbenzenos/uso terapêutico , Ácidos Heptanoicos/efeitos adversos , Ácidos Heptanoicos/uso terapêutico , Humanos , Masculino , Proteínas de Membrana Transportadoras/fisiologia , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Niacina/efeitos adversos , Niacina/uso terapêutico , Pirimidinas/efeitos adversos , Pirimidinas/uso terapêutico , Pirróis/efeitos adversos , Pirróis/uso terapêutico , Quinolinas/efeitos adversos , Quinolinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência , Rosuvastatina Cálcica , Receptores Depuradores Classe B/fisiologia , Sulfonamidas/efeitos adversos , Sulfonamidas/uso terapêutico , Taxa de Sobrevida , Regulação para Cima/fisiologia
16.
Eur J Neurol ; 17(6): 767-73, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20402744

RESUMO

OBJECTIVE: To provide evidence-based guidelines to general neurologists for the assessment of patients with pauci- or asymptomatic hyperCKemia. BACKGROUND: Recent epidemiologic studies show that up to 20% of 'normal' individuals have an elevated creatine kinase activity in the serum (sCK). The possibility of a subclinical myopathy is often raised, and patients may be unnecessarily denied treatment with statins. SEARCH STRATEGY: Electronic databases including Medline, the Cochrane Library and the American Academy of Neurology were searched for existing guidelines. Articles dealing with series of patients investigated for asymptomatic/pauci-symptomatic hyperCKemia and articles dealing with myopathies that can present with asymptomatic hyperCKemia were identified and reviewed. RESULTS: The only guidelines found were those approved by the Italian Association of Myology Committee, and the only relevant articles identified describe class IV studies. RECOMMENDATIONS: HyperCKemia needs to be redefined as values beyond 1.5 times the upper limit of normal (which itself needs to be appropriately defined). Pauci- or asymptomatic hyperCKemia with no apparent medical explanation may be investigated with a muscle biopsy if one or more of the following are present; the sCK is >or=3x normal, the electromyogram is myopathic or the patient is <25 years of age. In addition, women with sCK<3 times normal may be offered DNA testing because of the possibility of carrying a dystrophin mutation.


Assuntos
Creatina Quinase/sangue , Doenças Musculares/sangue , Doenças Musculares/diagnóstico , Feminino , Humanos , Doenças Musculares/enzimologia , Valores de Referência
17.
Nature ; 425(6958): 602-5, 2003 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-14534582

RESUMO

If the rich functionality of organic molecules is to be exploited in devices such as light-emitting diodes or field-effect transistors, interface properties of organic materials with various (metallic and insulating) substrates must be tailored carefully. In many cases, this calls for well-ordered interfaces. Organic epitaxy-that is, the growth of molecular films with a commensurate structural relationship to their crystalline substrates--relies on successful recognition of preferred epitaxial sites. For some large pi-conjugated molecules ('molecular platelets') this works surprisingly well, even if the substrate exhibits no template structure into which the molecules can lock. Here we present an explanation for site recognition in non-templated organic epitaxy, and thus resolve a long-standing puzzle. We propose that this form of site recognition relies on the existence of a local molecular reaction centre in the extended pi-electron system of the molecule. Its activity can be controlled by appropriate side groups and--in a certain regime--may also be probed by molecularly sensitized scanning tunnelling microscopy. Our results open the possibility of engineering epitaxial interfaces, as well as other interfacial nanostructures for which specific site recognition is essential.

18.
J Fish Biol ; 76(6): 1498-507, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20537028

RESUMO

A new species of Profundulus, Profundulus portillorum, from the Honduran central highlands is described. Profundulus portillorum belongs to the Profundulus labialis species group and is distinct from the Profundulus punctatus species group in that it lacks a humeral spot and less than half of the caudal fin is scaled. Within the P. labialis species group, P. portillorum has a more slender body, smaller eye, fewer anal rays, caudal rays and lateral-line scales than other species. Forty-one specimens were collected around emergent vegetation in the margins of two small (2-5 m in width, 20-40 cm in depth), high-elevation (1300 m) tributaries of the Río Calam within the Río Ulúa drainage. These specimens represent the easternmost collection of any Profundulus and the first collection of any member of the P. labialis species group from Honduras.


Assuntos
Ciprinodontiformes/classificação , Animais , Ciprinodontiformes/anatomia & histologia , Água Doce , Honduras , Análise Multivariada , Análise de Componente Principal
19.
Sci Adv ; 6(38)2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32938673

RESUMO

Glacial lake outburst floods (GLOFs) are a substantial hazard for downstream communities in vulnerable regions, yet unpredictable triggers and remote source locations make GLOF dynamics difficult to measure and quantify. Here, we revisit a destructive GLOF that occurred in Bhutan in 1994 and apply cross-correlation-based seismic analyses to track the evolution of the GLOF remotely (~100 kilometers from the source region). We use the seismic observations along with eyewitness reports and a downstream gauge station to constrain a numerical flood model and then assess geomorphic change and current state of the unstable lakes via satellite imagery. Coherent seismic energy is evident from 1 to 5 hertz beginning approximately 5 hours before the flood impacted Punakha village, which originated at the source lake and advanced down the valley during the GLOF duration. Our analysis highlights potential benefits of using real-time seismic monitoring to improve early warning systems.

20.
Genes Immun ; 10(1): 18-26, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18754015

RESUMO

Although cells of the immune system can produce thyroid-stimulating hormone (TSH), the significance of that remains unclear. Using 5' rapid amplification of cDNA ends (RACE), we show that mouse bone marrow (BM) cells produce a novel in-frame TSHbeta splice variant generated from a portion of intron 4 with all of the coding region of exon 5, but none of exon 4. The TSHbeta splice variant gene was expressed at low levels in the pituitary, but at high levels in the BM and the thyroid, and the protein was secreted from transfected Chinese hamster ovary (CHO) cells. Immunoprecipitation identified an 8 kDa product in lysates of CHO cells transfected with the novel TSHbeta construct, and a 17 kDa product in lysates of CHO cells transfected with the native TSHbeta construct. The splice variant TSHbeta protein elicited a cAMP response from FRTL-5 thyroid follicular cells and a mouse alveolar macrophage (AM) cell line. Expression of the TSHbeta splice variant, but not the native form of TSHbeta, was significantly upregulated in the thyroid during systemic virus infection. These studies characterize the first functional splice variant of TSHbeta, which may contribute to the metabolic regulation during immunological stress, and may offer a new perspective for understanding autoimmune thyroiditis.


Assuntos
Processamento Alternativo , Células da Medula Óssea/metabolismo , Glândula Tireoide/metabolismo , Tireotropina Subunidade beta/genética , Regulação para Cima , Sequência de Aminoácidos , Animais , Células CHO , Cricetinae , Cricetulus , Meios de Cultura/química , Éxons , Feminino , Íntrons , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Hipófise/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Secundária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Infecções por Reoviridae/genética , Infecções por Reoviridae/metabolismo , Tireotropina Subunidade beta/biossíntese , Tireotropina Subunidade beta/química , Transfecção
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