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1.
Sci Adv ; 10(24): eadl2286, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38865449

RESUMEN

Müllerian mimicry was proposed to be an example of a coevolved mutualism promoted by population isolation in glacial refugia. This, however, has not been well supported in butterfly models. Here, we use genomic data to test this theory while examining the population genetics behind mimetic diversification in a pair of co-mimetic bumble bees, Bombus breviceps Smith and Bombus trifasciatus Smith. In both lineages, populations were structured by geography but not as much by color pattern, suggesting sharing of color alleles across regions of restricted gene flow and formation of mimicry complexes in the absence of genetic differentiation. Demographic analyses showed mismatches between historical effective population size changes and glacial cycles, and niche modeling revealed only mild habitat retraction during glaciation. Moreover, mimetic subpopulations of the same color form in the two lineages only in some cases exhibit similar population history and genetic divergence. Therefore, the current study supports a more complex history in this comimicry than a simple refugium-coevolution model.


Asunto(s)
Mimetismo Biológico , Animales , Abejas/genética , Abejas/fisiología , Mimetismo Biológico/genética , Refugio de Fauna , Evolución Biológica , Flujo Génico , Genética de Población , Filogenia , Ecosistema , Coevolución Biológica , Variación Genética
2.
Mol Biol Evol ; 40(12)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039153

RESUMEN

Müllerian mimicry provides natural replicates ideal for exploring mechanisms underlying adaptive phenotypic divergence and convergence, yet the genetic mechanisms underlying mimetic variation remain largely unknown. The current study investigates the genetic basis of mimetic color pattern variation in a highly polymorphic bumble bee, Bombus breviceps (Hymenoptera, Apidae). In South Asia, this species and multiple comimetic species converge onto local Müllerian mimicry patterns by shifting the abdominal setal color from orange to black. Genetic crossing between the orange and black phenotypes suggested the color dimorphism being controlled by a single Mendelian locus, with the orange allele being dominant over black. Genome-wide association suggests that a locus at the intergenic region between 2 abdominal fate-determining Hox genes, abd-A and Abd-B, is associated with the color change. This locus is therefore in the same intergenic region but not the same exact locus as found to drive red black midabdominal variation in a distantly related bumble bee species, Bombus melanopygus. Gene expression analysis and RNA interferences suggest that differential expression of an intergenic long noncoding RNA between abd-A and Abd-B at the onset setal color differentiation may drive the orange black color variation by causing a homeotic shift late in development. Analysis of this same color locus in comimetic species reveals no sequence association with the same color shift, suggesting that mimetic convergence is achieved through distinct genetic routes. Our study establishes Hox regions as genomic hotspots for color pattern evolution in bumble bees and demonstrates how pleiotropic developmental loci can drive adaptive radiations in nature.


Asunto(s)
Mimetismo Biológico , Estudio de Asociación del Genoma Completo , Abejas/genética , Animales , Fenotipo , Mimetismo Biológico/genética , Edición Génica , ADN Intergénico/genética
3.
Nat Commun ; 14(1): 6615, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857626

RESUMEN

The pressing crisis of clean water shortage requires membranes to possess effective ion sieving as well as fast water flux. However, effective ion sieving demands reduction of pore size, which inevitably hinders water flux in hydrophilic membranes, posing a major challenge for efficient water/ion separation. Herein, we introduce anomalous water molecular gating based on nanofiltration membranes full of graphene capillaries at 6 Å, which were fabricated from spontaneous π-π restacking of island-on-nanosheet graphitic microstructures. We found that the membrane can provide effective ion sieving by suppressing osmosis-driven ion diffusion to negligible levels (~10-4 mol m-2 h-1); unexpectedly, ultrafast bulk flow of water (45.4 L m-2 h-1) was still functional with ease, as gated on/off by adjusting hydrostatic pressures within only 10-2 bar. We attribute this seemingly incompatible observation to graphene nanoconfinement effect, where crystal-like water confined within the capillaries hinders diffusion under osmosis but facilitates high-speed, diffusion-free water transport in the way analogous to Newton's cradle-like Grotthus conduction. This strategy establishes a type of liquid-solid-liquid, phase-changing molecular transport for precise and ultrafast molecular sieving.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(3): 856-60, 2015 Jun.
Artículo en Chino | MEDLINE | ID: mdl-26117050

RESUMEN

OBJECTIVE: To investigate the changes of physiological activities and functions in vitro of apheresis platelets during storage. METHOD: 17 units of apheresis platelets were randomly chosen and stored at 20 °C to 24 °C with agitation. Platelet counting (Plt), mean platelet volume (MPV), blood gases, pH value, glucose (Glu) concentration, lactate (LA) concentration, LDH concentration, thromboelastogram (TEG), hypotonic shock response (HSR), CD62p expression rate and anew expression rate were measured on days 0, 1, 3, 5 after platelet storage. Changes of physiological activities and functions in vitro were systematically evaluated by above-mentioned indexes. RESULTS: During storage, Plt, MPV and HSR were not significantly changed; but pH value, blood gases, Glu, LA, LDH, HSR, expression rate of CD62p and anew expression rate were significant differenty. Among thromboelastogram indexes, R value increased obviously with prolongation of storage time; K value and αAngle were not significantly changed; MA was not significantly changed on day 1 and 3, but was slightly increase on day 5. CONCLUSION: The physiological activities and functions in vitro of apheresis platelets are kept well during storage. For clinical transfusion of apheresis platelet during storage, clinical effect of transfusione is not influenced.


Asunto(s)
Plaquetas , Conservación de la Sangre , Humanos , Técnicas In Vitro , Recuento de Plaquetas , Plaquetoferesis , Tromboelastografía
5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(3): 861-5, 2015 Jun.
Artículo en Chino | MEDLINE | ID: mdl-26117051

RESUMEN

OBJECTIVE: To analyze the results of irregular antibody screening and identification among patients before blood transfusion, and to investigate the specific distribution of irregular antibodies and the distribution regularity in different diseases. METHODS: Choosing the patients intended to be transfused in our hospital from January 1, 2009 to December 31, 2013 years, micro-column gel technique was used to screen the irregular antibodies of those receptors and to identify the antibody specificity of the positive specimens. RESULTS: Among 44194 patients, 137 patients were with irregular antibody positive and their positive rate was 0.31%, among them 33 cases were male and accounted for 0.18% in the studied males; the 104 cases were females and accounted for 0.40% in all the studied females. The difference of sex distribution was statistically significant (X2=15.38, P<0.05). In the irregular antibody screening positive patients, patients with transfusion or pregnancy history were 129 cases, and the patients without transfusion or pregnancy history were 8 cases. In the irregular antibody screening positive patients, the main antibody of 54 cases belongs to Rh blood type system, accounting for 39.42%; The main antibody of 37 cases belongs to MNS blood type system, accounting for 27.01%; while the 30 cases belong to Lewis blood type system, accounting for 21.90%. According to the classification of diseases, the irregular antibody screening-positive patients with tumors were ranked in the highest rate at 5.96‰, the secondary hemorrhage of digestive tract and chronic renal failure were ranked at the rate of 3.28‰ and 3.19‰. The difference of positive rates between diseases was statistically significant (χ2=19.33, P<0.05). CONCLUSION: Irregular antibody screening before blood transfusion is necessary, which can discover the irregular antibodies of clinical significance, especially for patients with tumors and the other patients with the history of frequent blood transfusions or multiple pregnancies. Antibody screening is a useful warning signal, as it ensures the safety of blood transfusions.


Asunto(s)
Transfusión Sanguínea , Sistema del Grupo Sanguíneo Rh-Hr , Anticuerpos , Antígenos de Grupos Sanguíneos , Tipificación y Pruebas Cruzadas Sanguíneas , Femenino , Tracto Gastrointestinal , Humanos , Antígenos del Grupo Sanguíneo de Lewis , Masculino , Embarazo
6.
Tumour Biol ; 35(3): 1827-31, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24363083

RESUMEN

The objective of this study was to investigate the expression and significance of the GRHL3 protein in breast cancer diagnosis and prognosis. Overall, 111 patients with histologically confirmed breast cancer who had undergone radical surgery were enrolled in this study. The GRHL3 protein expression status in the breast cancers was evaluated by immunohistochemistry. The relationship between GRHL3 protein expression status and clinicopathological factors and the breast cancer prognoses was also determined. In total, 71 (63.96%) out of 111 cases were found to express GRHL3 protein. GRHL3 expression was higher in breast cancers, compared to other pathologic cancer types (χ (2) = 5.68, P < 0.05). Moreover, GRHL3 protein was also observed to correlate with breast cancer clinical stage and histological grade (χ (2) = 7.99, P < 0.05 and χ (2) = 7.907, P < 0.05, respectively). Interestingly, triple-negative breast cancers had lower expression rates than other breast cancers (41.18 vs. 71.28%, P < 0.05). GRHL3 was shown to be an independent prognostic factor of breast cancer in Cox regression analysis. Altogether, our results indicate predominant GRHL3 expression in breast cancers, especially non-triple-negative cancers and early stage cancers. GRHL3 expression appeared to decrease with tumor progression. Survival analysis demonstrated the inhibitory effect of GRHL3 in breast cancer. These results strongly suggest the possible involvement of GRHL3 in tumor suppression.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/metabolismo , Proteínas de Unión al ADN/biosíntesis , Factores de Transcripción/biosíntesis , Adulto , Anciano , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Proteínas de Unión al ADN/análisis , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Transcripción/análisis
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