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1.
Proc Natl Acad Sci U S A ; 121(24): e2321619121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833475

RESUMO

Angiotensin-convertingenzyme 2 (ACE2) has dual functions, regulating cardiovascular physiology and serving as the receptor for coronaviruses. Bats, the only true flying mammals and natural viral reservoirs, have evolved positive alterations in traits related to both functions of ACE2. This suggests significant evolutionary changes in ACE2 during bat evolution. To test this hypothesis, we examine the selection pressure in ACE2 along the ancestral branch of all bats (AncBat-ACE2), where powered flight and bat-coronavirus coevolution occurred, and detect a positive selection signature. To assess the functional effects of positive selection, we resurrect AncBat-ACE2 and its mutant (AncBat-ACE2-mut) created by replacing the positively selected sites. Compared to AncBat-ACE2-mut, AncBat-ACE2 exhibits stronger enzymatic activity, enhances mice's performance in exercise fatigue, and shows lower affinity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our findings indicate the functional pleiotropy of positive selection in the ancient ACE2 of bats, providing an alternative hypothesis for the evolutionary origin of bats' defense against coronaviruses.


Assuntos
Enzima de Conversão de Angiotensina 2 , Quirópteros , Seleção Genética , Quirópteros/virologia , Quirópteros/genética , Animais , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Camundongos , Pleiotropia Genética , Evolução Molecular , SARS-CoV-2/genética , COVID-19/virologia , COVID-19/genética , Coronavirus/genética , Humanos , Filogenia
2.
BMC Med Imaging ; 24(1): 125, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802734

RESUMO

PURPOSE: Accurate prognostication may aid in the selection of patients who will benefit from surgery at recurrent WHO grade 4 glioma. This study aimed to evaluate the role of serial tumour volumetric measurements for prognostication at first tumour recurrence. METHODS: We retrospectively analyzed patients with histologically-diagnosed WHO grade 4 glioma at initial and at first tumour recurrence at a tertiary hospital between May 2000 and September 2018. We performed auto-segmentation using ITK-SNAP software, followed by manual adjustment to measure serial contrast-enhanced T1W (CE-T1W) and T2W lesional volume changes on all MRI images performed between initial resection and repeat surgery. RESULTS: Thirty patients met inclusion criteria; the median overall survival using Kaplan-Meier analysis from second surgery was 10.5 months. Seventeen (56.7%) patients received treatment post second surgery. Univariate cox regression analysis showed that greater rate of increase in lesional volume on CE-T1W (HR = 2.57; 95% CI [1.18, 5.57]; p = 0.02) in the last 2 MRI scans leading up to the second surgery was associated with a higher mortality likelihood. Patients with higher Karnofsky Performance Score (KPS) (HR = 0.97; 95% CI [0.95, 0.99]; p = 0.01) and who received further treatment following second surgery (HR = 0.43; 95% CI [0.19, 0.98]; p = 0.04) were shown to have a better survival. CONCLUSION: Higher rate of CE-T1W lesional growth on the last 2 MRI images prior to surgery at recurrence was associated with increase mortality risk. A larger prospective study is required to determine and validate the threshold to distinguish rapidly progressive tumour with poor prognosis.


Assuntos
Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia , Humanos , Glioma/diagnóstico por imagem , Glioma/mortalidade , Glioma/cirurgia , Glioma/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Estudos Retrospectivos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Prognóstico , Idoso , Gradação de Tumores , Carga Tumoral , Estimativa de Kaplan-Meier
3.
J Clin Pediatr Dent ; 48(2): 204-208, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38548651

RESUMO

Impacted supernumerary teeth are defined as the presence of one or more teeth in a patient's upper and lower jaws in addition to the normal number of teeth in the dental arch. It has an incidence rate of approximately 1%-14% and more frequently occurs in males than females, may be single or multiple, unilateral or bilateral, erupted or impacted. In this article, we describe the case of a patient with two supernumerary teeth between the roots of the mandibular second premolar and the first molar, which influenced the effectiveness of the first orthodontic treatment. The special anatomical position of the complex supernumerary teeth made tooth extraction challenging. Given the higher risk status of surgery, we implemented a novel tooth extracting technique for this patient. Thus, in this study, we describe a case of minimally invasive extraction of bilateral mandibular impacted supernumerary teeth using a digital 3D positioning guide plate.


Assuntos
Dente Impactado , Dente Supranumerário , Masculino , Feminino , Humanos , Dente Supranumerário/diagnóstico por imagem , Dente Supranumerário/cirurgia , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia , Mandíbula/cirurgia , Extração Dentária/efeitos adversos , Extração Dentária/métodos , Dente Pré-Molar
4.
J Neurosci ; 42(43): 8169-8183, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36100398

RESUMO

Aquaporin-4 (AQP4) is characterized by the formation of orthogonal arrays of particles (OAPs) comprising its M1 and M23 isoforms in the plasma membrane. However, the biological importance of OAP formation is obscure. Here, we developed an OAP depolymerization male mouse model by transgenic knock-in of an AQP4-A25Q mutation. Analyses of the mutant brain tissue using blue native polyacrylamide gel electrophoresis, super-resolution imaging, and immunogold electron microscopy revealed remarkably reduced OAP structures and glial endfeet localization of the AQP4-A25Q mutant protein without effects on its overall mRNA and protein expression. AQP4A25Q/A25Q mice showed better survival and neurologic deficit scores when cerebral edema was induced by water intoxication or middle cerebral artery occlusion/reperfusion. The brain water content and swelling of pericapillary astrocytic endfeet processes in AQP4A25Q/A25Q mice were significantly reduced, functionally supporting decreased AQP4 protein expression at the blood-brain barrier. The infarct volume and neuronal damage were also reduced in AQP4A25Q/A25Q mice in the middle cerebral artery occlusion/reperfusion model. Astrocyte activation in the brain was alleviated in AQP4A25Q/A25Q mice, which may be associated with decreased cell swelling. We conclude that the OAP structure of AQP4 plays a key role in its polarized expression in astrocytic endfeet processes at the blood-brain barrier. Therefore, our study provided new insights into intervention of cerebral cellular edema caused by stroke and traumatic brain injury through regulating AQP4 OAP formation.SIGNIFICANCE STATEMENT Aquaporin-4 (AQP4) is characterized by orthogonal arrays of particles (OAPs) comprising the M1 and M23 isoforms in the membrane. Here, an OAP depolymerization male mouse model induced by AQP4-A25Q mutation was first established, and the functions of OAP depolymerization in cerebral edema have been studied. The results revealed that AQP4 lost its OAP structure without affecting AQP4 mRNA and protein levels in AQP4-A25Q mice. AQP4-A25Q mutation mice has neuroprotective effects on cerebral edema induced by water intoxication and middle cerebral artery occlusion/reperfusion through relieving the activation of astrocytes and suppressed microglia-mediated neuroinflammation. We concluded that the OAP structure of AQP4 plays a key role in its polarized expression in astrocytic endfeet processes at the blood-brain barrier. Therefore, our study provided new insights into intervention of cerebral cellular edema caused by stroke and traumatic brain injury through regulating AQP4 OAP formation.


Assuntos
Aquaporina 4 , Edema Encefálico , Lesões Encefálicas Traumáticas , Fármacos Neuroprotetores , Intoxicação por Água , Animais , Masculino , Camundongos , Aquaporina 4/genética , Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Edema Encefálico/genética , Edema Encefálico/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Membrana Celular/metabolismo , Edema/metabolismo , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fármacos Neuroprotetores/metabolismo , Mutação Puntual , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Intoxicação por Água/metabolismo
5.
Biogerontology ; 24(4): 581-592, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37052773

RESUMO

There is growing evidence that extracellular vesicles (EVs) play a functional role in tissue repair and anti-aging by transferring the contents of donor cells to recipient cells. We hypothesized that Dauer (C. elegans), known as "ageless" nematodes, can also secrete extracellular vesicles and influence the lifespan of C. elegans. Here, we isolated EVs of dauer larvae (dauer EVs). Dauer EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA), and Western blot analysis. Wild-type C. elegans were fed in the presence or absence of dauer EVs and tested for a range of phenotypes, including longevity, mobility and reproductive capacity. Results showed that dauer EVs increased the average lifespan of nematodes by 15.74%, improved mobility, slowed age-related pigmentation as well as body length, and reduced the accumulation of reactive oxygen species and lipids, while not impairing nematode reproductive capacity. These findings suggest that dauer EVs can extend the lifespan of C. elegans as well as the healthy lifespan by reducing ROS accumulation, with potential anti-aging capacity.


Assuntos
Proteínas de Caenorhabditis elegans , Vesículas Extracelulares , Animais , Caenorhabditis elegans/genética , Larva , Envelhecimento , Proteínas de Caenorhabditis elegans/genética , Longevidade/genética
6.
Hematol Oncol ; 40(4): 554-566, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35416325

RESUMO

Sustained expression of B-cell receptor (BCR) critically contributes to the development of diffuse large B-cell lymphoma (DLBCL). However, little is known on the mechanism regulating BCR expression. In the present study, we explored the biological significance of functional intergenic repeating RNA element (FIRRE) in DLBCL and its regulation on BCR. Functional impacts of FIRRE on cell viability, transformation, and apoptosis were examined by MTT, colony formation, and flow cytometry, respectively. The interaction between FIRRE and polypyrimidine tract binding protein 1 (PTBP1) was identified by RNA pull-down and verified using RNA immunoprecipitation (RIP) assays. The effects of FIRRE and PTBP1 on Smurf2 mRNA were examined by RIP, RNA pull-down, and mRNA stability assays. Smurf2-mediated BCR ubiquitination was investigated using co-immunoprecipitation, ubiquitination, and protein stability assays. In vivo, xenograft models were used to assess the impacts of targeting FIRRE on DLBCL growth. FIRRE was specifically up-regulated in and essentially maintained multiple malignant behaviors of BCR-dependent DLBCL cells. Through the interaction with PTBP1, FIRRE promoted the mRNA decay of Smurf2, a ubiquitin ligase for the degradation BCR protein. Targeting FIRRE was sufficient to regulat Smurf2 and BCR expressions and inhibit DLBCL malignancy both in vivo and in vitro. FIRRE-PTBP1 interaction, by simulating Smurf2 mRNA decay and stabilizing BCR, promotes the development of DLBCL. Consequently, targeting this signaling mechanism may provide therapeutic benefits for DLBCL.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas , Linfoma Difuso de Grandes Células B , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Longo não Codificante , Receptores de Antígenos de Linfócitos B , Ubiquitina-Proteína Ligases , Linhagem Celular Tumoral , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Ligases/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , RNA Longo não Codificante/genética , RNA Mensageiro , Receptores de Antígenos de Linfócitos B/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
7.
J Neuroeng Rehabil ; 19(1): 46, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549977

RESUMO

BACKGROUND: Reducing the energy cost of running with exoskeletons could improve enjoyment, reduce fatigue, and encourage participation among novice and ageing runners. Previously, tethered ankle exoskeleton emulators with offboard motors were used to greatly reduce the energy cost of running with powered ankle plantarflexion assistance. Through a process known as "human-in-the-loop optimization", the timing and magnitude of assistance torque was optimized to maximally reduce metabolic cost. However, to achieve the maximum net benefit in energy cost outside of the laboratory environment, it is also necessary to consider the tradeoff between the magnitude of device assistance and the metabolic penalty of carrying a heavier, more powerful exoskeleton. METHODS: In this study, tethered ankle exoskeleton emulators were used to characterize the effect of peak assistance torque on metabolic cost during running. Three recreational runners participated in human-in-the-loop optimization at four fixed peak assistance torque levels to obtain their energetically optimal assistance timing parameters at each level. RESULTS: We found that the relationship between metabolic rate and peak assistance torque was nearly linear but with diminishing returns at higher torque magnitudes, which is well-approximated by an asymptotic exponential function. At the highest assistance torque magnitude of 0.8 Nm/kg, participants' net metabolic rate was 24.8 ± 2.3% (p = 4e-6) lower than running in the unpowered devices. Optimized timing of peak assistance torque was as late as allowed during stance (80% of stance) and optimized timing of torque removal was at toe-off (100% of stance); similar assistance timing was preferred across participants and torque magnitudes. CONCLUSIONS: These results allow exoskeleton designers to predict the energy cost savings for candidate devices with different assistance torque capabilities, thus informing the design of portable ankle exoskeletons that maximize net metabolic benefit.


Assuntos
Exoesqueleto Energizado , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos , Metabolismo Energético , Marcha , Humanos , Torque , Caminhada
8.
Eur Radiol ; 31(5): 3347-3354, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33185752

RESUMO

OBJECTIVES: To evaluate the diagnostic value and reproducibility of T2 mapping versus apparent diffusion coefficients (ADC) for identifying malignant lymph nodes in patients with non-mucinous rectal adenocarcinoma. METHODS: High-resolution magnetic resonance imaging, diffusion-weighted imaging, and T2 mapping were performed on patients with suspected metastatic lymph nodes in the mesorectum or around the superior rectal artery with a short-axis diameter of 4-10 mm. The T2 and ADC values of pathology-confirmed metastatic versus non-metastatic lymph nodes were compared using the independent-samples t test and receiver operating characteristic curves. Intra- and inter-observer reproducibility were tested. The cutoff value for T2 relaxation time was determined. RESULTS: In total, 67 lymph nodes underwent histological analysis, with 24 in the non-metastatic and 43 in the metastatic groups. Intra- and inter-observer agreements for T2 values were 0.999 and 0.998, respectively, which were higher than the ADC values of 0.924 and 0.844, respectively. The mean T2 and ADC values for metastatic lymph nodes (65 ± 7.8 ms and 1.17 ± 0.16 × 10-3 mm2/s, respectively) were significantly lower than for benign lymph nodes(83 ± 5.7 ms and 1.29 ± 0.15 × 10-3 mm2/s, respectively). T2 values had a higher AUC value of 0.990 than the AUC value for ADC of 0.729. With a cutoff value of 77 ms, sensitivity and specificity for T2 values were 95% and 96%, respectively. CONCLUSIONS: T2 mapping had higher diagnostic efficacy and reproducibility than ADC and may be useful in differentiating metastatic from non-metastatic lymph nodes in rectal cancer. KEY POINTS: • Mean T2 values were significantly shorter for malignant versus benign LNs in patients with non-mucinous rectal adenocarcinoma. • The diagnostic efficacy and reproducibility of T2 values were excellent and superior to ADC values.


Assuntos
Linfonodos , Neoplasias Retais , Imagem de Difusão por Ressonância Magnética , Estudos de Viabilidade , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Curva ROC , Neoplasias Retais/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Phys Chem Chem Phys ; 23(7): 4120-4132, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33592085

RESUMO

We outline a nonparametric inversion strategy for determining the orientation distribution function (ODF) of sheared interacting rods using small-angle scattering techniques. With the presence of direct inter-rod interaction and fluid mechanical forces, the scattering spectra are no longer characterized by the azimuthal symmetry in the coordinates defined by the principal directions of simple shear conditions, which severely compounds the reconstruction of ODFs based on currently available methods developed for dilute systems. Using a real spherical harmonic expansion scheme, the real-space ODFs are uniquely determined from the anisotropic scattering spectra and their numerical accuracy is verified computationally. Our method can be generalized to extract ODFs of uniaxially anisotropic objects under different flow conditions in a properly transformed reference frame with suitable basis vectors.

10.
Blood Purif ; 50(6): 800-807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33530090

RESUMO

OBJECTIVE: Prepump arterial (Pa) pressure indicates the ease or difficulty with which the blood pump can draw blood from the vascular access (VA) during hemodialysis. Some studies have suggested that the absolute value of the Pa pressure to the extracorporeal blood pump flow (Qb) ratio set on the machine (|Pa/Qb|) can reflect the dysfunction of VA. This study was conducted to explore the impact of arteriovenous fistula (AVF) dysfunction and to explore the clinical reference value of |Pa/Qb|. METHODS: We retrospectively identified adults who underwent hemodialysis at 3 hospitals. Data were acquired from electronic health records. We evaluated the pattern of the association between |Pa/Qb| and AVF dysfunction during 1 year using a Cox proportional hazards regression model with restricted cubic splines. Then, the patients were grouped based on the results, and hazard ratios were compared for different intervals of |Pa/Qb|. RESULTS: A total of 490 patients were analyzed, with an average age of 55 (44, 66) years. There were a total of 85 cases of AVF dysfunction, of which 50 cases were stenosis and 35 cases were thrombosis. There was a U-shaped association between |Pa/Qb| and the risk of AVF dysfunction (p for nonlinearity <0.001). |Pa/Qb| values <0.30 and >0.52 increased the risk of AVF dysfunction. Compared with the group with a |Pa/Qb| value between 0.30 and 0.52, the groups with |Pa/Qb| <0.30 and |Pa/Qb| >0.52 had a 4.04-fold (p = 0.002) and 3.41-fold (p < 0.001) greater risk of AVF dysfunction, respectively. CONCLUSIONS: The appropriate range of |Pa/Qb| is between 0.30 and 0.52. When |Pa/Qb| is <0.30 or >0.52, the patient's AVF function or Qb setting should be reevaluated to prevent subsequent failure.


Assuntos
Pressão Arterial , Fístula Arteriovenosa/etiologia , Diálise Renal/efeitos adversos , Adulto , Idoso , Fístula Arteriovenosa/fisiopatologia , Fístula Arteriovenosa/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Risco , Fatores de Risco
11.
Am J Physiol Cell Physiol ; 318(5): C836-C847, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32159363

RESUMO

Prostate cancer (PCa) is a leading cause of cancer death in men. Despite the antiproliferative effects of 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] on PCa, accumulating evidence indicates that 1,25(OH)2D3 promotes cancer progression by increasing genome plasticity. Our investigation of epigenetic changes associated with vitamin D insensitivity found that 1,25(OH)2D3 treatment reduced the expression levels and activities of DNA methyltransferases 1 and 3B (DNMT1 and DNMT3B, respectively). In silico analysis and reporter assay confirmed that 1,25(OH)2D3 downregulated transcriptional activation of the DNMT3B promoter and upregulated microRNAs targeting the 3'-untranslated regions of DNMT3B. We then profiled DNA methylation in the vitamin D-resistant PC-3 cells and a resistant PCa cell model generated by long-term 1,25(OH)2D3 exposure. Several candidate genes were found to be hypomethylated and overexpressed in vitamin D-resistant PCa cells compared with vitamin D-sensitive cells. Most of the identified genes were associated with mammalian target of rapamycin (mTOR) signaling activation, which is known to promote cancer progression. Among them, we found that inhibition of ribosomal protein S6 kinase A1 (RPS6KA1) promoted vitamin D sensitivity in PC-3 cells. Furthermore, The Cancer Genome Atlas (TCGA) prostate cancer data set demonstrated that midline 1 (MID1) expression is positively correlated with tumor stage. Overall, our study reveals an inhibitory mechanism of 1,25(OH)2D3 on DNMT3B, which may contribute to vitamin D resistance in PCa.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferases/genética , Neoplasias da Próstata/genética , Vitamina D/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Serina-Treonina Quinases TOR/genética , Ubiquitina-Proteína Ligases/genética , Vitamina D/análogos & derivados , Vitamina D/genética , Vitamina D/farmacologia , DNA Metiltransferase 3B
12.
Anal Chem ; 92(17): 11600-11606, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32693574

RESUMO

Development of highly sensitive and selective fluorescent sensors toward hazardous analytes represents great progress in fabricating sensing devices for practical applications. In this work, a highly selective sensor with dual functions has been fabricated via facile postmodification of the UiO-MOF. Butene modified salicylaldehyde is covalently linked to the UiO-66 scaffold via an efficient Schiff-base reaction, resulting in a highly fluorescent ozone sensor of UiO-66-butene. Ozonolysis of the terminal olefin followed by ß-elimination could significantly quench the bright blue fluorescence of UiO-66-butene, and linear turn-off detection of ozone in the range of 0-100 µM is well established. The detection is highly sensitive and selective, and a detection limit of 73 nM was calculated. Remarkably, the ozonolysis afforded product could further act as a selective sensor for Al3+ via turn-on fluorescence with a detection limit of 142 nM, representing a second potential sensing function. The chemically selective sequential ozonolysis/ß-elimination and remarkable dual functions offer the exclusive detection of ozone over other oxidative species as well as Al3+ over other cations following a tandem process, representing the first example of a direct MOF sensor for dual sensing of ozone and Al3+. This work demonstrates the potential of employing combinatorial principles for fabricating highly selective sensors, and postmodification of MOFs represents a promising facile strategy for developing various functional sensors.

13.
Plant Biotechnol J ; 18(2): 389-401, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31278885

RESUMO

Landraces often contain genetic diversity that has been lost in modern cultivars, including alleles that confer enhanced local adaptation. To comprehensively identify loci associated with adaptive traits in soya bean landraces, for example flowering time, a population of 1938 diverse landraces and 97 accessions of the wild progenitor of cultivated soya bean, Glycine soja was genotyped using tGBS® . Based on 99 085 high-quality SNPs, landraces were classified into three sub-populations which exhibit geographical genetic differentiation. Clustering was inferred from STRUCTURE, principal component analyses and neighbour-joining tree analyses. Using phenotypic data collected at two locations separated by 10 degrees of latitude, 17 trait-associated SNPs (TASs) for flowering time were identified, including a stable locus Chr12:5914898 and previously undetected candidate QTL/genes for flowering time in the vicinity of the previously cloned flowering genes, E1 and E2. Using passport data associated with the collection sites of the landraces, 27 SNPs associated with adaptation to three bioclimatic variables (temperature, daylength, and precipitation) were identified. A series of candidate flowering genes were detected within linkage disequilibrium (LD) blocks surrounding 12 bioclimatic TASs. Nine of these TASs exhibit significant differences in flowering time between alleles within one or more of the three individual sub-populations. Signals of selection during domestication and/or subsequent landrace diversification and adaptation were detected at 38 of the 44 flowering and bioclimatic TASs. Hence, this study lays the groundwork to begin breeding for novel environments predicted to arise following global climate change.


Assuntos
Adaptação Fisiológica , Genes de Plantas , Estudo de Associação Genômica Ampla , Glycine max , Adaptação Fisiológica/genética , Alelos , Genes de Plantas/genética , Genótipo , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Glycine max/genética
14.
Inorg Chem ; 59(4): 2536-2547, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31977197

RESUMO

Structurally precise copper hydrides [Cu11H2{S2P(OiPr)2}6(C≡CR)3], R = Ph (1), C6H4F (2), and C6H4OMe (3), were first synthesized from the polyhydrido copper cluster [Cu20H11{S2P(OiPr)2}9] with nine equivalents of terminal alkynes. Later, their isolated yields were significantly improved by direct synthesis from [Cu(CH3CN)4](PF6), [NH4][S2P(OiPr)2], NaBH4, and alkynes along with NEt3 in THF. 1, 2, and 3 were fully characterized by single-crystal X-ray diffraction, ESI-MS, and multinuclear NMR spectroscopy. All three clustershave 11 copper atoms, adopting 3,3,4,4,4-pentacapped trigonal prismatic geometry, with two hydrides inside the Cu11 cage, the position of which was ascertained by a single-crystal neutron diffraction structure of cluster 1 co-crystallized with a [Cu7(H){S2P(OiPr)2}6] (4) cluster. Six dithiophosphate and three alkynyl ligands stabilize the Cu11H2 core in which the two hydrides adopt a trigonal pyramidal coordination mode. This coordination mode is so far unprecedented for hydride. The 1H NMR resonance frequency of the two hydrides appears at 4.8 ppm, a value further confirmed by 2H NMR spectroscopy for their deuteride derivatives [Cu11(D)2{S2P(OiPr)2}6(C≡CR)3]. A DFT investigation allows understanding the bonding within this new type of copper(I) hydrides.

15.
J Chem Phys ; 153(18): 184902, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33187411

RESUMO

Self-assembly of amphiphilic polymers in water is of fundamental and practical importance. Significant amounts of free unimers and associated micellar aggregates often coexist over a wide range of phase regions. The thermodynamic and kinetic properties of the microphase separation are closely related to the relative population density of unimers and micelles. Although the scattering technique has been employed to identify the structure of micellar aggregates as well as their time-evolution, the determination of the population ratio of micelles to unimers remains a challenging problem due to their difference in scattering power. Here, using small-angle neutron scattering (SANS), we present a comprehensive structural study of amphiphilic n-dodecyl-PNIPAm polymers, which shows a bimodal size distribution in water. By adjusting the deuterium/hydrogen ratio of water, the intra-micellar polymer and water distributions are obtained from the SANS spectra. The micellar size and number density are further determined, and the population densities of micelles and unimers are calculated to quantitatively address the degree of micellization at different temperatures. Our method can be used to provide an in-depth insight into the solution properties of microphase separation, which are present in many amphiphilic systems.

16.
Curr Microbiol ; 77(8): 1448-1456, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32198535

RESUMO

Coix lachrymal-jobi L. var. ma-yuen Stapf of Gramineae are annual or perennial herbs and an important food-medicine homologous plants of high value in nutrition, health protection, and comprehensive utilization. In recent years, the revival of researches on its roles in food and medicinal applications of this underutilized grass for food security and economic empowerment of rural communities has been seen . In this research, Coix kernel endophytic fungi were isolated and identified by fungal colony morphology observation combined with the PCR-amplified fungal internal transcribed spacer (ITS) sequence analyses. All together six isolates to five species of Coix endophytic fungi and two isolates to the genus level were identified from the kernels of six Coix cultivars: Penicillium expansum, Penicillium polonicum, Cladosporium cladosporioides, Alternaria alternata, Aspergillus flavus, and two genera of Aspergillus and Fusarium. Potential benefits and harms analyses showed that Penicillium expansum, Aspergillus oryzae, and Cladosporium cladosporioides can produce a variety of beneficial composite enzymes and have an extensive application in microbial chemistry, food science, and fermentation, whereas Penicillium, Aspergillus flavus, Alternaria alternate, and Fusarium can produce corresponding toxins harmful to plants, animals, and humans. These results not only provided a basis for the targeted prevention of contamination in the tissue culture of Coix kernels by the addition of specific antibiotics, but also enriched the endophytic fungi resource pool of Gramineae crops and suggested new ideas for the improvement, cultivation, post-harvest seeds/kernels storage, and the development of new natural drugs.


Assuntos
Coix/microbiologia , Fungos/classificação , Sementes/microbiologia , Aspergillus/classificação , Aspergillus/isolamento & purificação , China , Cladosporium/classificação , Cladosporium/isolamento & purificação , DNA Fúngico/genética , DNA Intergênico/genética , Endófitos/classificação , Endófitos/isolamento & purificação , Fungos/isolamento & purificação , Genoma Fúngico , Penicillium/classificação , Penicillium/isolamento & purificação
17.
Phys Chem Chem Phys ; 21(33): 18346-18351, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31397831

RESUMO

Surfactants are amphiphilic molecules that spontaneously self-assemble in aqueous solution into various ordered and disordered phases. Under certain conditions, one-dimensional structures in the form of long, flexible wormlike micelles can develop. Cetyltrimethylammonium bromide (CTAB) is one of the most widely studied surfactants, and in the presence of sodium salicylate (NaSal), wormlike micelles can form at very dilute concentrations of surfactant. We carry out a systematic study of the structures of CTAB/NaSal over a surfactant concentration range of 2.5-15 mM and at salt-to-surfactant molar ratios of 0.5-10. Using small-angle neutron scattering (SANS), we qualitatively and quantitatively characterize the equilibrium structures of CTAB/NaSal, mapping the phase behavior of CTAB/NaSal at low concentrations within the region of phase space where nascent wormlike micelles transition into long and entangled structures. Complementary rheological assessments not only demonstrate the significant influence of the inter-micellar Coulombic interaction on the micellar structure but also suggest the potential existence of a hierarchical structure which is beyond the accessibility of the SANS technique.

18.
J Med Internet Res ; 21(2): e10404, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30714941

RESUMO

BACKGROUND: Patients with early-stage breast cancer have numerous options when choosing the type of breast surgery method to be applied. Each of these options lead to a similar long-term survival rate, but result in significant differences in appearance, function, cost, recurrence rate, and various other relevant considerations. However, the time available for detailed communication with each patient is often limited in clinics, which puts these women under great psychological stress and can hinder their surgery-related decision making. OBJECTIVE: The objective of this study was to develop a multipurpose surgery decision-making website providing medical information, psychological support, and decision-related simulation for women during breast cancer surgery-related decision making. METHODS: Using the 4 steps of action research, which involve multigroup teamwork via regular team meetings, the following were performed: (1) Planning: searching, analyzing, and evaluating health websites to consensually decide the major infrastructure; (2) Action: work was performed simultaneously in 4 groups, which consisted of medical information collection and editing, patient interviews and data extraction, webpage content design, and programming to create or host the website; (3) Evaluation: the website was tested by clinical experts and focus groups of former breast cancer patients to assess its effectiveness and pinpoint appropriate improvements; and (4) Reflection: constant dialogue was conducted between the various participants at each step, which was used as the foundation and motivation of next plan-action-evaluation-reflection circle. RESULTS: Using the action research approach, we completed the development of our website, which includes the following: (1) "Woman's Voice"-an animated comic depicting the story of a female breast cancer patient with interspersed questions for the users that will help them better empathize with the experience; (2) "Cancer Information Treasure House"-providing breast cancer surgery-related information through text, tables, pictures and a presentation video; (3) "Decision-making Simulator"-helping patients think through and check the pros and cons of the different surgical options via visual-based interactions including "Stairs Climbing" and "Fruit of Hope"; and (4) "Recommended Links"-providing reliable websites for further reference. Additionally, we have further improved the website based on the feedback received from postsurgery breast cancer patients and clinicians. We hope to continue improving to better meet both the patients' and health providers' needs and become a practical decision-making aid for patients undergoing breast cancer surgery. CONCLUSIONS: We have created the first breast cancer surgery decision-making assistance tool in Taiwan using a "Web-based" and multifunctional website design. This site aims to provide health care knowledge, psychological healing, and emotional support functions, as well as decision-making capability enhancement simulations. We look forward to assisting breast cancer patients in their decision-making process and expect our website to increase patient's autonomy and improve their communication with clinicians.


Assuntos
Neoplasias da Mama/cirurgia , Técnicas de Apoio para a Decisão , Feminino , Humanos , Internet
19.
Int J Mol Sci ; 20(18)2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31540158

RESUMO

The mediator complex is an essential link between transcription factors and RNA polymerase II, and mainly functions in the transduction of diverse signals to genes involved in different pathways. Limited information is available on the role of soybean mediator subunits in growth and development, and their participation in defense response regulation. Here, we performed genome-wide identification of the 95 soybean mediator subunits, which were unevenly localized on the 20 chromosomes and only segmental duplication events were detected. We focused on GmMED16-1, which is highly expressed in the roots, for further functional analysis. Transcription of GmMED16-1 was induced in response to Phytophthora sojae infection. Agrobacterium rhizogenes mediated soybean hairy root transformation was performed for the silencing of the GmMED16-1 gene. Silencing of GmMED16-1 led to an enhanced susceptibility phenotype and increased accumulation of P. sojae biomass in hairy roots of transformants. The transcript levels of NPR1, PR1a, and PR5 in the salicylic acid defense pathway in roots of GmMED16-1-silenced transformants were lower than those of empty-vector transformants. The results provide evidence that GmMED16-1 may participate in the soybean-P. sojae interaction via a salicylic acid-dependent process.


Assuntos
Estudo de Associação Genômica Ampla , Glycine max/genética , Glycine max/parasitologia , Interações Hospedeiro-Parasita/genética , Complexo Mediador/metabolismo , Phytophthora/fisiologia , Mapeamento Cromossômico , Cromossomos de Plantas , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Filogenia , Phytophthora/classificação , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Subunidades Proteicas , Transcriptoma
20.
Molecules ; 24(10)2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31130654

RESUMO

This study aimed to investigate whether the anti-tumor effect of gemcitabine (GEM) in non-small-cell lung cancer (NSCLC) treatment was affected by Danggui Buxue decoction (DBD), and explore the potential mechanisms. The combined use of GEM and DBD showed an enhanced tumor growth inhibition effect in a murine Lewis lung carcinoma (LLC) model. LC-MS/MS results showed that the pharmacokinetic behaviors of a GEM active metabolite, gemcitabine triphosphate (dFdCTP), were found to be altered remarkably in the peripheral blood mononuclear cells (PBMC) of DBD co-administration rats. In addition, after co-administration of DBD with GEM, Western Blot and qPCR results confirmed that the expression of deoxycytidine kinase (dCK) in tumor tissues of LLC-bearing mice were markedly increased. DBD co-administration also reversed the upregulation of P-glycoprotein (P-gp) in tumor tissues induced by GEM. Moreover, DBD could notably up-regulate the IL-12p70 and GM-CSF expression in mice serum, suggesting potential immunomodulatory activities in tumor-bearing mice. Meanwhile, DBD inhibited the P-gp efflux activity in A549 cells. Therefore, the regulation of dCK and P-gp played important roles in the alternation of GEM pharmacokinetics and the enhancement of the anti-tumor effect of GEM. DBD being a potential dCK promoter could work as an adjuvant agent to boost the anticancer effect of GEM.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Desoxicitidina Quinase/metabolismo , Desoxicitidina/análogos & derivados , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Animais , Desoxicitidina/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Gencitabina
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