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1.
Eur Radiol ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662099

RESUMEN

OBJECTIVES: Basilar artery occlusion (BAO) may be etiologically attributed to embolism or in situ thrombosis due to basilar stenosis (BS). Patients with BAO due to BS (BAOS) are known to have worse outcomes than patients with embolic occlusions (BAOE). BAOS occurs more proximally in the basilar artery (BA) than BAOE. We hypothesize that differing brain stem infarct patterns contribute to outcome differences between these stroke etiologies. METHODS: This retrospective study includes 199 consecutive patients with BAO who received endovascular treatment at a single center. Final infarction in brain parenchyma dependent on the posterior circulation was graded semiquantitatively on magnetic resonance imaging (MRI). Associations to underlying stenosis and angiographic and clinical outcome variables were tested. The primary endpoint was early good clinical outcome (EGCO, mRS score ≤ 3 at discharge). RESULTS: Infarct extension of the medulla oblongata (OR = 0.25; 95% CI = 0.07-0.86; p = 0.03), the inferior pons (OR = 0.328; 95% CI = 0.17-0.63; p = 0.001), the superior pons (OR = 0.57; 95% CI = 0.33-0.99; p = 0.046), and the occipital lobes (OR = 0.46; 95% CI = 0.26-0.80; p = 0.006) negatively predicted EGCO. Infarct extension for other posterior-circulation-dependent brain regions was not independently associated with unfavorable early outcomes. Patients with BAOS had more proximal occlusions and greater infarct volumes in the inferior brain stem. Successful reperfusion (mTICI 2b-3) occurred more often in patients with BAOE than in BAOS (BAOE: 131 (96.3%); BAOS: 47 (83.9%), p = 0.005). CONCLUSION: Unfavorable early outcomes in patients with BAOS may be explained by a higher likelihood of inferior brain stem infarcts and lower rates of reperfusion success. CLINICAL RELEVANCE STATEMENT: Basilar artery occlusion due to underlying stenosis is associated with a poorer prognosis than that caused by embolism; these results suggest that aggressive endovascular therapy, usually involving the placement of a permanent stent, may be warranted in these patients. KEY POINTS: Inferior brain stem and occipital infarcts are prognostically unfavorable in basilar artery occlusion. Basilar artery occlusion due to stenosis occurs more proximally and is associated with worse outcomes. Differentiating etiologies of basilar artery occlusion may influence how aggressively treated the occlusion is.

2.
J Chem Phys ; 156(16): 164106, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35489992

RESUMEN

A semi-automatic sampling and fitting procedure for generating sum-of-product (Born-Oppenheimer) potential energy surfaces based on a high-dimensional model representation is presented. The adaptive sampling procedure and subsequent fitting rely on energies only and can be used for re-fitting existing analytic potential energy surfaces in the sum-of-product form or for direct fits from ab initio computations. The method is tested by fitting ground electronic state potential energy surfaces for small to medium sized semi-rigid molecules, i.e., HFCO, HONO, and HCOOH, based on ab initio computations at the coupled-cluster single double and perturbative triples-F12/cc-pVTZ-F12 or MP2/aug-cc-pVTZ levels of theory. Vibrational eigenstates are computed using block improved relaxation in the Heidelberg multi-configurational time dependent Hartree package and compared to available experimental and theoretical data. The new potential energy surfaces are compared to the best ones currently available for these molecules in terms of accuracy, including resulting vibrational states, required number of sampling points, and number of fitting parameters. The present procedure leads to compact expansions and scales well with the number of dimensions for simple potentials such as single or double wells.

3.
Circ Res ; 125(3): 282-294, 2019 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-31213138

RESUMEN

RATIONALE: Fluid shear stress (FSS) maintains NOS-3 (endothelial NO synthase) expression. Homozygosity for the C variant of the T-786C single-nucleotide polymorphism of the NOS3 gene, which solely exists in humans, renders the gene less sensitive to FSS, resulting in a reduced endothelial cell (EC) capacity to generate NO. Decreased bioavailability of NO in the arterial vessel wall facilitates atherosclerosis. Consequently, individuals homozygous for the C variant have an increased risk for coronary heart disease (CHD). OBJECTIVE: At least 2 compensatory mechanisms seem to minimize the deleterious effects of this single-nucleotide polymorphism in affected individuals, one of which is characterized herein. METHODS AND RESULTS: Human genotyped umbilical vein ECs and THP-1 monocytes were used to investigate the role of 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) in vitro. Its concentration in plasma samples from genotyped patients with CHD and age-matched CHD-free controls was determined using quantitative ultraperformance LC-MS/MS. Exposure of human ECs to FSS effectively reduced monocyte transmigration particularly through monolayers of CC-genotype ECs. Primarily in CC-genotype ECs, FSS elicited a marked rise in COX (cyclooxygenase)-2 and L-PGDS (lipocalin-type prostaglandin D synthase) expression, which appeared to be NO sensitive, and provoked a significant release of 15d-PGJ2 over baseline. Exogenous 15d-PGJ2 significantly reduced monocyte transmigration and exerted a pronounced anti-inflammatory effect on the transmigrated monocytes by downregulating, for example, transcription of the IL (interleukin)-1ß gene (IL1B). Reporter gene analyses verified that this effect is due to binding of Nrf2 (nuclear factor [erythroid-derived 2]-like 2) to 2 AREs (antioxidant response elements) in the proximal IL1B promoter. In patients with CHD, 15d-PGJ2 plasma levels were significantly upregulated compared with age-matched CHD-free controls, suggesting that this powerful anti-inflammatory prostanoid is part of an endogenous defence mechanism to counteract CHD. CONCLUSIONS: Despite a reduced capacity to form NO, CC-genotype ECs maintain a robust anti-inflammatory phenotype through an enhanced FSS-dependent release of 15d-PGJ2.


Asunto(s)
Células Endoteliales/metabolismo , Óxido Nítrico Sintasa de Tipo III/deficiencia , Óxido Nítrico/sangre , Polimorfismo de Nucleótido Simple , Prostaglandina D2/análogos & derivados , Adaptación Fisiológica , Anciano , Anciano de 80 o más Años , Enfermedad Coronaria/sangre , Enfermedad Coronaria/genética , Ciclooxigenasa 2/biosíntesis , Ciclooxigenasa 2/genética , Inducción Enzimática , Femenino , Genes Reporteros , Predisposición Genética a la Enfermedad , Hemorreología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Inflamación , Oxidorreductasas Intramoleculares/biosíntesis , Oxidorreductasas Intramoleculares/genética , Lipocalinas/biosíntesis , Lipocalinas/genética , Masculino , Persona de Mediana Edad , Factor 2 Relacionado con NF-E2/fisiología , Óxido Nítrico Sintasa de Tipo III/genética , Prostaglandina D2/biosíntesis , Prostaglandina D2/sangre , Prostaglandina D2/fisiología , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Células THP-1
4.
Angew Chem Int Ed Engl ; 60(3): 1176-1186, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33006797

RESUMEN

We report the extension of the class of organotetrel sulfide clusters with further examples of the still rare silicon-based species, synthesized from RSiCl3 with R=phenyl (Ph, I), naphthyl (Np, II), and styryl (Sty, III) with Na2 S. Besides known [(PhSi)4 S6 ] (IV), new compounds [(NpSi)4 S6 ] (1) and [(StySi)4 S6 ] (2) were obtained, the first two of which underwent reactions with [AuCl(PPh3 )] to form ternary complexes. DFT studies of cluster dimers helped us understand the differences between the habit of {Si4 S6 }- and {Sn4 S6 }-based compounds. Crystalline 1 showed a pronounced nonlinear optical response, while for intrinsically amorphous 2, the chemical damage threshold seems to inhibit a corresponding observation. Calculations within the independent particle approximation served to rationalize and compare electronic and optical excitations of [(RSi)4 S6 ] clusters (R=Ph, Np). The calculations reproduced the measured data and allowed for the interpretation of the main spectroscopic features.

5.
Hautarzt ; 69(11): 916-921, 2018 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-30135969

RESUMEN

Scleromyxedema is a rare disorder that frequently affects multiple extracutaneous organ systems and is usually associated with monoclonal gammopathy. The pathogenesis of scleromyxedema is unknown. The clinical course is chronic and progressive and can lead to marked morbidity or death. The skin findings consist of multiple waxy papules and indurated plaques. Progressive skin involvement can lead to decreased mobility of the mouth and joints. Extracutaneous manifestations occur in the musculoskeletal or cardiovascular system, in the gastrointestinal or respiratory tract, or in the kidneys. There are no approved or evidence-based treatment options available for scleromyxedema. High-dose immunoglobulins are considered the treatment of choice, followed by lenalidomide (or thalidomide) and systemic glucocorticosteroids, or in severe cases even autologous hematopoetic stem cell transplantation. Long-term maintenance treatment is usually required and close clinical follow-up is necessary as recurrence of scleromyxedema is common after withdrawal of an effective therapy.


Asunto(s)
Escleromixedema , Humanos , Lenalidomida , Enfermedades Raras , Recurrencia , Escleromixedema/diagnóstico , Escleromixedema/terapia
6.
J Evol Biol ; 29(9): 1804-11, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27296092

RESUMEN

Male-haploidy has independently evolved several times in different phylogenetic groups and has led to various extant lineages in the insects, Arachnida and Rotifera. Although the stability of male-haploidy as an evolutionary strategy is not well understood, various theories address the invasion of male-haploidy in diploid populations. Here two of these theories: (i) the maternal transmission hypothesis (MTH) and (ii) the deleterious mutation hypothesis (DMH), are re-investigated with an agent-based model to understand the role of genetic drift as a mechanism facilitating the spread of male-haploidy. These two hypotheses are analysed separately and comparatively, and the results suggest dominance of the MTH. In addition, comparison of the stochastic results to deterministic results using the same model structure shows how genetic drift can enhance the parameter space where male-haploidy can be expected to invade.


Asunto(s)
Diploidia , Flujo Genético , Haploidia , Filogenia , Animales , Masculino , Modelos Genéticos
7.
Naturwissenschaften ; 102(3-4): 17, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25813053

RESUMEN

The allocation of large numbers of workers facilitates the swift intake of locally available resources which is essential for ant colony survival. To organise the traffic between nest and food source, the black-meadow ant Formica pratensis establishes permanent trunk trails, which are maintained by the ants. To unravel the ant organisation and potential traffic rules on these trails, we analysed velocity and lane segregation under various densities by experimentally changing feeding regimes. Even under the highest ant densities achieved, we never observed any traffic jams. On the contrary, velocity increased after supplementary feeding despite an enhanced density. Furthermore, inbound ants returning to the nest had a higher velocity than those leaving the colony. Whilst at low and medium density the ants used the centre of the trail, they used the full width of the trail at high density. Outbound ants also showed some degree of lane segregation which contributes to traffic organisation.


Asunto(s)
Himenópteros/fisiología , Actividad Motora/fisiología , Animales , Tamaño Corporal , Densidad de Población
8.
Anim Genet ; 45(2): 267-73, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24320562

RESUMEN

Nosema is a microsporidian parasite of the honeybee, which infects the epithelial cells of the gut. In Denmark, honeybee colonies have been selectively bred for the absence of Nosema over decades, resulting in a breeding line that is tolerant toward Nosema infections. As the tolerance toward the Nosema infection is a result of artificial selection, we screened chromosome 14 for a selective sweep with microsatellite markers, where a major quantitative trait locus (QTL) had been identified to be involved in the reduction in Nosema spores in the honeybees. By comparing the genetic variability of 10 colonies of the selected honeybee strain with a population sample from 22 unselected colonies, a selective sweep was revealed within the previously identified QTL region. The genetic variability of the swept loci was not only reduced in relation to the flanking markers on chromosome 14 within the selected strain but also significantly reduced compared with the same region in the unselected honeybees. This confirmed the results of the previous QTL mapping for reduced Nosema infections. The success of the selective breeding may have driven the selective sweep found in our study.


Asunto(s)
Abejas/genética , Resistencia a la Enfermedad/genética , Interacciones Huésped-Parásitos/genética , Nosema/fisiología , Selección Genética , Animales , Abejas/parasitología , Cruzamiento , Dinamarca , Genotipo , Nosema/patogenicidad
10.
Front Endocrinol (Lausanne) ; 15: 1352048, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38440788

RESUMEN

Objectives: To quantitatively investigate the age- and sex-related longitudinal changes in trabecular volumetric bone mineral density (vBMD) and vertebral body volume at the thoracolumbar spine in adults. Methods: We retrospectively included 168 adults (mean age 58.7 ± 9.8 years, 51 women) who received ≥7 MDCT scans over a period of ≥6.5 years (mean follow-up 9.0 ± 2.1 years) for clinical reasons. Level-wise vBMD and vertebral body volume were extracted from 22720 thoracolumbar vertebrae using a convolutional neural network (CNN)-based framework with asynchronous calibration and correction of the contrast media phase. Human readers conducted semiquantitative assessment of fracture status and bony degenerations. Results: In the 40-60 years age group, women had a significantly higher trabecular vBMD than men at all thoracolumbar levels (p<0.05 to p<0.001). Conversely, men, on average, had larger vertebrae with lower vBMD. This sex difference in vBMD did not persist in the 60-80 years age group. While the lumbar (T12-L5) vBMD slopes in women only showed a non-significant trend of accelerated decline with age, vertebrae T1-11 displayed a distinct pattern, with women demonstrating a significantly accelerated decline compared to men (p<0.01 to p<0.0001). Between baseline and last follow-up examinations, the vertebral body volume slightly increased in women (T1-12: 1.1 ± 1.0 cm3; L1-5: 1.0 ± 1.4 cm3) and men (T1-12: 1.2 ± 1.3 cm3; L1-5: 1.5 ± 1.6 cm3). After excluding vertebrae with bony degenerations, the residual increase was only small in women (T1-12: 0.6 ± 0.6 cm3; L1-5: 0.7 ± 0.7 cm3) and men (T1-12: 0.7 ± 0.6 cm3; L1-5: 1.2 ± 0.8 cm3). In non-degenerated vertebrae, the mean change in volume was <5% of the respective vertebral body volumes. Conclusion: Sex differences in thoracolumbar vBMD were apparent before menopause, and disappeared after menopause, likely attributable to an accelerated and more profound vBMD decline in women at the thoracic spine. In patients without advanced spine degeneration, the overall volumetric changes in the vertebral body appeared subtle.


Asunto(s)
Caracteres Sexuales , Cuerpo Vertebral , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Anciano , Densidad Ósea , Estudios Retrospectivos , Columna Vertebral
11.
Front Neurosci ; 17: 1156319, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37139521

RESUMEN

The potential of psychedelics to persistently treat substance use disorders is known since the 1960s. However, the biological mechanisms responsible for their therapeutic effects have not yet been fully elucidated. While it is known that serotonergic hallucinogens induce changes in gene expression and neuroplasticity, particularly in prefrontal regions, theories on how specifically this counteracts the alterations that occur in neuronal circuitry throughout the course of addiction are largely unknown. This narrative mini-review endeavors to synthesize well-established knowledge from addiction research with findings and theories regarding the neurobiological effects of psychedelics to give an overview of the potential mechanisms that underlie the treatment of substance use disorders with classical hallucinogenic compounds and point out gaps in the current understanding.

12.
Front Endocrinol (Lausanne) ; 14: 1222041, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37576975

RESUMEN

Objectives: Opportunistic quantitative computed tomography (oQCT) derived from non-dedicated routine CT has demonstrated high accuracy in diagnosing osteoporosis and predicting incident vertebral fractures (VFs). We aimed to investigate the cost-effectiveness of oQCT screening compared to dual-energy X-ray absorptiometry (DXA) as the standard of care for osteoporosis screening. Methods: Three screening strategies ("no osteoporosis screening", "oQCT screening", and "DXA screening") after routine CT were simulated in a state-transition model for hypothetical cohorts of 1,000 patients (women and men aged 65 years) over a follow-up period of 5 years (base case). The primary outcomes were the cumulative costs and the quality-adjusted life years (QALYs) estimated from a U.S. health care perspective for the year 2022. Cost-effectiveness was assessed based on a willingness-to-pay (WTP) threshold of $70,249 per QALY. The secondary outcome was the number of prevented VFs. Deterministic and probabilistic sensitivity analyses were conducted to test the models' robustness. Results: Compared to DXA screening, oQCT screening increased QALYs in both sexes (additional 2.40 per 1,000 women and 1.44 per 1,000 men) and resulted in total costs of $3,199,016 and $950,359 vs. $3,262,934 and $933,077 for women and men, respectively. As a secondary outcome, oQCT screening prevented 2.6 and 2.0 additional VFs per 1,000 women and men, respectively. In the probabilistic sensitivity analysis, oQCT screening remained cost-effective in 88.3% (women) and 90.0% (men) of iterations. Conclusion: oQCT screening is a cost-effective ancillary approach for osteoporosis screening and has the potential to prevent a substantial number of VFs if considered in daily clinical practice.


Asunto(s)
Osteoporosis , Fracturas de la Columna Vertebral , Masculino , Humanos , Femenino , Análisis Costo-Beneficio , Densidad Ósea , Osteoporosis/diagnóstico por imagen , Osteoporosis/epidemiología , Tamizaje Masivo/métodos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología
13.
ACS Nano ; 17(11): 10474-10485, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37212793

RESUMEN

Quantum sensing with spin defects in diamond, such as the nitrogen vacancy (NV) center, enables the detection of various chemical species on the nanoscale. Molecules or ions with unpaired electronic spins are typically probed by their influence on the NV center's spin relaxation. Whereas it is well-known that paramagnetic ions reduce the NV center's relaxation time (T1), here we report on the opposite effect for diamagnetic ions. We demonstrate that millimolar concentrations of aqueous diamagnetic electrolyte solutions increase the T1 time of near-surface NV center ensembles compared to pure water. To elucidate the underlying mechanism of this surprising effect, single and double quantum NV experiments are performed, which indicate a reduction of magnetic and electric noise in the presence of diamagnetic electrolytes. In combination with ab initio simulations, we propose that a change in the interfacial band bending due to the formation of an electric double layer leads to a stabilization of fluctuating charges at the interface of an oxidized diamond. This work not only helps to understand noise sources in quantum systems but could also broaden the application space of quantum sensors toward electrolyte sensing in cell biology, neuroscience, and electrochemistry.

14.
Vasa ; 41(4): 243-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22825857

RESUMEN

According to the guidelines and the manufacturer's information, pregnancy is a contraindication for sclerotherapy with Polidocanol. However, in some cases sclerotherapy has been conducted in a period when the pregnancy is not known by the patient. When pregnancy is diagnosed, patients and gynecologists often ask the phlebologist if there is an indication for the interruption of pregnancy. Up to now, there is only rare information on sclerotherapy, polidocanol and pregnancy. Current knowledge is summed up in this article together with case reports. The existing case reports and mainly retrospective case series on intended or accidentally conducted sclerotherapy with common sclerosants and doses show no increased risk for the mother and the unborn child. However, in view of the limited literature data available and the high probability for spontaneous regression of varicose veins postpartum, sclerotherapy should be avoided in pregnancy, if possible. Conservative measures during pregnancy or an elimination of varicose veins before pregnancy should be preferred. In single cases e.g. painful genitoanal varices, the use of sclerotherapy can be helpful even during pregnancy. Thereby, a very thorough clarification of the mother with a final written consent and an implementation according to the guidelines are especially important. According to the current data, there is no reason for an interruption after a sclerotherapy that has been conducted during undetected pregnancy.


Asunto(s)
Polietilenglicoles/efectos adversos , Primer Trimestre del Embarazo , Soluciones Esclerosantes/efectos adversos , Escleroterapia/efectos adversos , Telangiectasia/terapia , Várices/terapia , Adulto , Femenino , Humanos , Nacimiento Vivo , Polidocanol , Embarazo , Pruebas de Embarazo , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento
15.
J Occup Med Toxicol ; 17(1): 13, 2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35681207

RESUMEN

The Borna disease virus 1 (BoDV-1) causes severe and often fatal encephalitis in humans. The virus is endemic in parts of Germany, Liechtenstein, Switzerland and Austria. As an increasing number of human BoDV-1 encephalitis cases is being diagnosed, the chance for healthcare professionals to come into contact with infected tissues and bodily fluids from patients with known acute bornavirus encephalitis is also increasing. Therefore, risk assessments are needed. Based on three different incidences of possible exposure to BoDV-1 including an autopsy knife injury, a needlestick injury, and a spill accident with cerebrospinal fluid from patients with acute BoDV-1 encephalitis, we perform risk assessments and review published data. BoDV-1 infection status of the index patient's tissues and bodily fluids to which contact had occurred should be determined. There is only scarce evidence for possible postexposure prophylaxis, serology, and imaging in healthcare professionals who possibly came into contact with the virus. Despite decade-long laboratory work with BoDV-1, not a single clinically apparent laboratory infection has been published. Given the increasing number of severe or fatal BoDV-1 encephalitis cases, there is a growing need for efficacy-tested, potent antiviral therapeutics against BoDV-1 in humans, both in clinically ill patients and possibly as postexposure prophylaxis in healthcare professionals.

16.
Sci Data ; 9(1): 762, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36496501

RESUMEN

Magnetic resonance imaging (MRI) is an important imaging modality in stroke. Computer based automated medical image processing is increasingly finding its way into clinical routine. The Ischemic Stroke Lesion Segmentation (ISLES) challenge is a continuous effort to develop and identify benchmark methods for acute and sub-acute ischemic stroke lesion segmentation. Here we introduce an expert-annotated, multicenter MRI dataset for segmentation of acute to subacute stroke lesions ( https://doi.org/10.5281/zenodo.7153326 ). This dataset comprises 400 multi-vendor MRI cases with high variability in stroke lesion size, quantity and location. It is split into a training dataset of n = 250 and a test dataset of n = 150. All training data is publicly available. The test dataset will be used for model validation only and will not be released to the public. This dataset serves as the foundation of the ISLES 2022 challenge ( https://www.isles-challenge.org/ ) with the goal of finding algorithmic methods to enable the development and benchmarking of automatic, robust and accurate segmentation methods for ischemic stroke.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Benchmarking
17.
J Evol Biol ; 24(2): 286-94, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21044209

RESUMEN

Determining the extent and causes of barriers to gene flow is essential for understanding sympatric speciation, but the practical difficulties of quantifying reproductive isolation remain an obstacle to analysing this process. Social parasites are common in eusocial insects and tend to be close phylogenetic relatives of their hosts (= Emery's rule). Sympatric speciation caused by reproductive isolation between host and parasite is a possible evolutionary pathway. Socially parasitic workers of the Cape honeybee, Apis mellifera capensis, produce female clonal offspring parthenogenetically and invade colonies of the neighbouring subspecies A. m. scutellata. In the host colony, socially parasitic workers can become pseudoqueens, an intermediate caste with queenlike pheromone secretion. Here, we show that over an area of approximately 275.000 km², all parasitic workers bear the genetic signature of a clone founded by a single ancestral worker genotype. Any gene flow from the host to the parasite is impossible because honeybee workers cannot mate. Gene flow from the parasite to the host is possible, as parasitic larvae can develop into queens. However, we show that despite sympatric coexistence for more than a decade, gene flow between host and social parasite (F(st) = 0.32) and hybridizations (0.71%) are rare, resulting in reproductive isolation. Our data suggest a new barrier to gene flow in sympatry, which is not based on assortative matings but on thelytoky and reproductive division of labour in eusocial insects, thereby suggesting a new potential pathway to Emery's rule.


Asunto(s)
Abejas/genética , Partenogénesis/genética , Animales , Abejas/clasificación , Femenino , Regulación de la Expresión Génica/genética , Flujo Génico , Variación Genética , Genotipo , Jerarquia Social
19.
J Proteomics ; 239: 104192, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33757883

RESUMEN

Pseudomonas aeruginosa is an important opportunistic human pathogen with high prevalence in nosocomial infections. This microorganism is a good model for understanding biological processes such as the quorum-sensing response, the metabolic integration of virulence, the mechanisms of global regulation of bacterial physiology, and the evolution of antibiotic resistance. Till now, P. aeruginosa proteomic data, although available in several on-line repositories, were dispersed and difficult to access. In the present work, proteomes of the PAO1 strain grown under different conditions and from diverse cellular compartments have been joined to build the Pseudomonas PeptideAtlas. This resource is a comprehensive mass spectrometry-derived peptide and inferred protein database with 71.3% coverage of the total predicted proteome of P. aeruginosa PAO1, the highest coverage among bacterial PeptideAtlas datasets. The proteins included cover 89% of metabolic proteins, 72% of proteins involved in genetic information processing, 83% of proteins responsible for environmental information processing, more than 88% of the ones related to quorum sensing and biofilm formation, and 89% of proteins responsible for antimicrobial resistance. It exemplifies a necessary tool for targeted proteomics studies, system-wide observations, and cross-species observational studies. The manuscript describes the building of the PeptideAtlas and the contribution of the different proteomic data used. SIGNIFICANCE: Pseudomonas aeruginosa is among the most versatile human bacterial pathogens. Studies of its proteome are very important as they can reveal virulence factors and mechanisms of antibiotic resistance. The construction of a proteomic resource such as the PeptideAtlas enables targeted proteomics studies, system-wide observations, and cross-species observational studies.


Asunto(s)
Proteómica , Pseudomonas aeruginosa , Proteínas Bacterianas , Biopelículas , Bases de Datos de Proteínas , Humanos , Proteoma , Percepción de Quorum
20.
J Exp Med ; 169(1): 363-8, 1989 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-2521242

RESUMEN

Recently, we described a murine helper T cell-derived molecule with T cell growth factor activity that is functionally and structurally distinct from IL-2, IL-4, and other known growth factors. This molecule, designated P40, was identified as a glycoprotein capable of supporting antigen-independent growth of certain helper T cell clones. Here, we report the cloning and expression of a cDNA for this new growth factor. The predicted mature protein is a cationic cysteine-rich polypeptide of 14 kD without significant homology to previously sequenced proteins.


Asunto(s)
Glicoproteínas/genética , Sustancias de Crecimiento/genética , Linfocinas/genética , Linfocitos T/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , Regulación de la Expresión Génica , Interleucina-9 , Ratones , Datos de Secuencia Molecular , ARN Mensajero/genética , Mapeo Restrictivo , Linfocitos T Colaboradores-Inductores/fisiología
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