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Specific ion effects in the interactions of monovalent anions with amine groupsâone of the hydrophilic moieties found in proteinsâwere investigated using octadecylamine monolayers floating at air-aqueous solution interfaces. We find that at solution pH 5.7, larger monovalent anions induce a nonzero pressure starting at higher areas/molecules, i.e., a wider "liquid expanded" region in the monolayer isotherms. Using X-ray fluorescence at near total reflection (XFNTR), an element- and surface-specific technique, ion adsorption to the amines at pH 5.7 is confirmed to be ion-specific and to follow the conventional Hofmeister series. However, at pH 4, this ion specificity is no longer observed. We propose that at the higher pH, the amine headgroups are only partially protonated, and large polarizable ions such as iodine are better able to boost amine protonation. At the lower pH, on the other hand, the monolayer is fully protonated, and electrostatic interactions dominate over ion specificity. These results demonstrate that ion specificity can be modified by changing the experimental conditions.
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Pulmonary surfactant forms a thin film on the liquid that lines the alveolar air-sacks. When compressed by the decreasing alveolar surface area during exhalation, the films avoid collapse from the air/water interface and reduce surface tension to exceptionally low levels. To define better the structure of compressed films that determines their susceptibility to collapse, we measured how cholesterol affects the structure and collapse of dipalmitoyl phosphatidylcholine (DPPC) monolayers at physiological temperatures. Grazing incidence X-ray diffraction (GIXD) and grazing incidence X-ray off-specular scattering (GIXOS) established the lateral and transverse structures of films on a Langmuir trough at a surface pressure of 45 mN m-1, just below the equilibrium spreading pressure at which collapse begins. Experiments with captive bubbles at a surface pressure of 51 mN m-1 measured how the steroid affects isobaric collapse. Mol fractions of the steroid (Xchol) at 0.05 removed the tilt by the acyl chains of DPPC, shifted the unit cell from centered rectangular to hexagonal, and dramatically decreased the long-range order. Higher Xchol produced no further change in diffraction, suggesting that cholesterol partitions into a coexisting disordered phase. Cholesterol had minimal effect on rates of collapse until Xchol reached 0.20. Our results demonstrate that the decreased coherence length, indicating conversion of positional order to short-range, is insufficient to make a condensed monolayer susceptible to collapse. Our findings suggest a two-step process by which cholesterol induces disorder. The steroid would first convert the film with crystalline chains to a hexatic phase before generating a fully disordered structure that is susceptible to collapse. These results lead to far-reaching consequences for formulation of animal-derived therapeutic surfactants. Our results suggest that removal of cholesterol from these preparations should be unnecessary below Xchol = 0.20.
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1,2-Dipalmitoilfosfatidilcolina , Colesterol , Surfactantes Pulmonares , Temperatura , Surfactantes Pulmonares/química , 1,2-Dipalmitoilfosfatidilcolina/química , Colesterol/químicaRESUMO
Intracerebral hemorrhage (ICH) is a severe stroke subtype. Secondary injury is a key factor leading to neurological deficits after ICH. Electroacupuncture (EA) can improve the neurological function after ICH, however, its internal mechanism is still unclear. The aim of this study is to investigate whether EA could ameliorate secondary injury after ICH through antioxidative stress and its potential regulatory mechanism. A rat model of ICH was established by injecting autologous blood into striatum. After the intervention of EA and EA combined with peroxisome proliferator-activated receptor-γ (PPARγ) blocker, Zea-longa scores, modified neurological severity scores and open field tests were used to evaluate the neurological function of the rats. Flow cytometry detected tissue reactive oxygen species (ROS) levels. Tissue tumor necrosis factor-α (TNF-α) levels were analyzed by enzyme-linked immunosorbent assays. The protein expressions of PPAR γ, nuclear factor erythroid2-related factor 2 (Nrf2) and γ-glutamylcysteine synthetase (γ-GCS) were detected by Western blot. Immunohistochemistry was used to observe the activation of microglia. The demyelination degree of axon myelin was observed by transmission electron microscope. Compared with the model group, EA intervention improved neurological function, decreased ROS and TNF-α levels, increased the protein expression of PPARγ, Nrf2 and γ-GCS, and reduced the activation of microglia, it also alleviated axonal myelin sheath damage. In addition, the neuroprotective effect of EA was partially attenuated by PPARγ blocker. EA ameliorated the neurological function of secondary injury after ICH in rats, possibly by activating the PPARγ/Nrf2/γ-GCS signaling pathway, reducing microglia activation, and inhibiting oxidative stress, thus alleviating the extent of axonal demyelination plays a role.
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Hemorragia Cerebral , Eletroacupuntura , Glutamato-Cisteína Ligase , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , PPAR gama , Ratos Sprague-Dawley , Animais , PPAR gama/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Eletroacupuntura/métodos , Estresse Oxidativo/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/complicações , Ratos , Masculino , Glutamato-Cisteína Ligase/metabolismo , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
The extractant-assisted transport of metal ions from aqueous to organic environments by liquid-liquid extraction has been widely used to separate and recover critical elements on an industrial scale. While current efforts focus on designing better extractants and optimizing process conditions, the mechanism that underlies ionic transport remains poorly understood. Here, we report a nonequilibrium process in the bulk aqueous phase that influences interfacial ion transport: the formation of metastable ion-extractant precipitates away from the liquid-liquid interface, separated from it by a depletion region without precipitates. Although the precipitate is soluble in the organic phase, the depletion region separates the two and ions are sequestered in a long-lived metastable state. Since precipitation removes extractants from the aqueous phase, even extractants that are sparingly soluble in water will continue to be withdrawn from the organic phase to feed the aqueous precipitation process. Solute concentrations in both phases and the aqueous pH influence the temporal evolution of the process and ionic partitioning between the precipitate and organic phase. Aqueous ion-extractant precipitation during liquid-liquid extraction provides a reaction path that can influence the extraction kinetics, which plays an important role in designing advanced processes to separate rare earths and other minerals.
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Epstein-Barr virus (EBV) causes infectious mononucleosis and is associated with B cell lymphomas. EBV glycoprotein 42 (gp42) binds HLA class II and activates membrane fusion with B cells. We isolated gp42-specific monoclonal antibodies (mAbs), A10 and 4C12, which use distinct mechanisms to neutralize virus infection. mAb A10 was more potent than the only known neutralizing gp42 mAb, F-2-1, in neutralizing EBV infection and blocking binding to HLA class II. mAb 4C12 was similar to mAb A10 in inhibiting glycoprotein-mediated B cell fusion but did not block receptor binding, and it was less effective in neutralizing infection. Crystallographic structures of gH/gL/gp42/A10 and gp42/4C12 complexes revealed two distinct sites of vulnerability on gp42 for receptor binding and B cell fusion. Passive transfer of mAb A10 into humanized mice conferred nearly 100% protection from viremia and EBV lymphomas after EBV challenge. These findings identify vulnerable sites on EBV that may facilitate therapeutics and vaccines.
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Benzenoacetamidas , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Piperidonas , Animais , Camundongos , Proteínas Virais/metabolismo , Glicoproteínas/metabolismo , Anticorpos AntiviraisRESUMO
Intracranial infections are among the most common complications of neurosurgery, with their incidence remaining high despite advancements in current neurosurgical techniques and aseptic technology. While the role of mucosal-associated invariant T (MAIT) cells, a subset of innate-like T lymphocytes, in bacterial defense is well-established, their involvement in intracranial infections remains unclear. In this study, we utilized flow cytometry to assess the phenotype and function of circulating and CSF MAIT cells. Our findings revealed that MAIT cells were higher in the CSF compared to blood. Notably, a higher percentage of IL-17A + MAIT cells was detected in the CSF of patients with intracranial infections. Moreover, markers indicating activation and exhaustion were significantly upregulated in CSF MAIT cells. Furthermore, elevated levels of pro-inflammatory cytokines, including IL-1ß, IL-12, and IL-18, were detected in the CSF supernatants. We hypothesized that the elevated levels of IL-1ß, IL-12, and IL-18 in the inflammatory milieu synergistically activate MAIT cells in the CSF. In particular, CD25 and Tim-3 expression of MAIT cells was increased by stimulation with IL-1ß, IL-12, and IL-18 or CSF supernatants of intracranial infection patients. Collectively, these findings provide important information underlying the innate immune response of patients with intracranial infections.
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Células T Invariantes Associadas à Mucosa , Humanos , Interleucina-18/metabolismo , Citocinas/metabolismo , Interleucina-12/metabolismo , CraniotomiaRESUMO
BACKGROUND: About 25% of pregnant women experience bleeding in the early stage, and half of them eventually progress to pregnancy loss. Progesterone serves as a useful biomarker to predict miscarriage in threatened miscarriage, yet its performance is still debated. AIM: To evaluate the performance of single serum progesterone predicting miscarriage in early pregnant patients with threatened miscarriage. METHOD: The online database was searched to yield the literature using the terms of 'Abortion', 'Miscarriage', and 'serum Progesterone', including PubMed, Scopus, Embase, Cochrane library, and China national knowledge infrastructure. Receiver operating characteristic (ROC) curve, likelihood ratio (LLR) and diagnostic odds ratio (DOR) and 95% confidence interval (CI) were computed. Publication bias was assessed by the deeks funnel plot asymmetry test. Subgroup analyses were conducted according to the progesterone level (< 12 ng/mL), recruited location and region, progesterone measurement method, exogenous progesterone supplement and follow up. RESULTS: In total, 12 studies were eligible to be included in this study, with sample sizes ranging from 76 to 1087. The included patients' gestational age was between 4 and 12 weeks. No significant publication bias was detected from all included studies. The threshold of progesterone reported ranged from 8 to 30 ng/ml. The synthesized area under the ROC curve (0.85, 95% CI 0.81 to 0.88), positive LLR (6.2, 4.0 to 9.7) and DOR (18, 12 to 27) of single progesterone measurement distinguishing miscarriage were relatively good in early pregnant patients with threatened miscarriage. When the threshold of < 12 ng/mL was adapted, the progesterone provided a higher area under the ROC curve (0.90 vs. 0.78), positive LLR (8.3 vs. 3.8) and DOR (22 vs.12) than its counterpart (12 to 30 ng/mL). CONCLUSION: Single progesterone measurement can act as a biomarker of miscarriage in early pregnant patients with threatened miscarriage, and it has a better performance when the concentration is <12 ng/mL. TRIAL REGISTRATION: PROSPERO (CRD42021255382).
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Ameaça de Aborto , Biomarcadores , Progesterona , Humanos , Progesterona/sangue , Gravidez , Feminino , Ameaça de Aborto/sangue , Ameaça de Aborto/diagnóstico , Biomarcadores/sangue , Aborto Espontâneo/sangue , Valor Preditivo dos Testes , Primeiro Trimestre da Gravidez/sangueRESUMO
Objective: To investigate the effect of icariin on the transformation efficiency of germ cell-like cells from mouse induced pluripotent stem cells into sperm cells in vitro. Methods: Firstly, mouse induced pluripotent stem cells were induced and cultured to transform into germ cell-like cells, and the primordial germ cell-like cells were identified by Western blot and RT-PCR. Then, different concentrations of icariin (0.1μg/mL, 1μg/mL, 10μg/mL and 100μg/mL) were added into the culture medium, and the obtained primitive germ cell-like cells were cultured, Western blot and RT-PCR were used to identify the obtained sperm cells, the transformation efficiency was compared. Results: The primordium germ cell-like cells obtained from mouse induced pluripotent stem cells in vitro specially expressed Oct-4 protein, C-kit protein, Mvh mRNA, Fragilis mRNA and Stella mRNA. The sperm cells were specially expressed VASA, SCP3 and γH2AX proteins. RT-PCR showed that the sperm cells were specially expressed Ddx4, Tp2 and Prm1 mRNA. Compared with the control group, the expression level of VASA protein (1.744±0.283, 2.882±0.373, 6.489±0.460), SCP3 protein (2.250±0.306, 7.058±0.521, 8.654±0.804), γH2AX protein (4.304±0.433, 5.713±0.339, 9.268±0.545), Ddx4 mRNA (1.374±0.145, 2.846±0.194, 4.021±0.154), Tp2 mRNA (1.358±0.130, 3.623±0.326, 5.811±0.390) and Prm1 mRNA (1.326±0.162, 3.487±0.237, 4.666±0.307) in 0.1μg/mL, 1μg/mL, 10μg/mL icariin experimental groups were all lower than that of VASA protein (10.560±0.413), SCP3 protein (13.804±0.642), γH2AX protein (11.874±0.464), Ddx4 mRNA (6.4005±0.361), Tp2 mRNA (7.314±0.256) and Prm1 mRNA (7.334±0.390) in 100μg/mL icariin experimental group. (AU)
Objetivo: Investigar el efecto de icariina en la eficiencia de la conversión in vitro inducida en espermatozoides de cultivos de células germinativas derivadas de la transformación de células madre pluripotentes inducidas de ratón. Métodos: Primero se indujeron y cultivaron células madre pluripotentes inducidas de ratón para transformarlas en células similares a las células germinales, y las células similares a las células germinales primordiales se identificaron mediante Western blot y RT-PCR. A continuación, se añadieron diferentes concentraciones de icariina (0,1μg/mL, 1μg/mL, 10μg/mL and 100μg/mL) al medio de cultivo, y se cultivaron las células primitivas similares a células germinales obtenidas, se utilizaron Western blot y RT-PCR para identificar las células espermáticas obtenidas, y se comparó la eficacia de la transformación. Resultados: Las células germinales primitivas obtenidas in vitro a partir de células madre pluripotentes inducidas de ratón expresaron especialmente la proteína Oct-4, la proteína C-kit, el ARNm de Mvh, el ARNm de Fragilis y el ARNm de Stella. Los espermatozoides expresaban especialmente las proteínas VASA, SCP3 y γH2AX. La RT-PCR mostró que los espermatozoides expresaban especialmente los ARNm Ddx4, Tp2 y Prm1. En comparación con el grupo de control, el nivel de expresión de la proteína VASA (1,744±0,283; 2,882±0,373; 6,489±0,460), la proteína SCP3 (2,250±0,306; 7,058± 0,521; 8,654±0,804), proteína γH2AX (4,304±0,433; 5,713±0,339; 9,268±0,545), ARNm Ddx4 (1,374±0,145; 2,846±0,194; 4,021±0,154), ARNm Tp2 (1,358±0,130; 3,623±0,326; 5,811±0,390) y ARNm Prm1 (1,326±0,162; 3,487±0,237; 4,666±0,307) en grupos experimentales de 0,1μg/mL, 1μg/mL, 10μg/mL de icariina fueron todos más bajos que los de la proteína VASA (10,560±0,413), proteína SCP3 (13,804±0,642), proteína γH2AX (11,874±0,464), ARNm Ddx4 (6,4005±0,361), ARNm Tp2 (7,314±0,256) y ARNm Prm1 (7,334±0,390) en 100μg/mL icariina grupo experimental. (AU)
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Animais , Camundongos , Epimedium , Células-Tronco Pluripotentes Induzidas , Infertilidade , Flavonoides/farmacologia , Flavonoides/efeitos adversos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/efeitos adversos , Sêmen , AzoospermiaRESUMO
A recently reported anionic gemini surfactant, a member of the so-called "gemini without a linker" family, has recently been reported to form closely packed crystalline monolayers at the air-water interface. In this work, the impact on monolayer properties of the compound, C18-0-C18, that result from its mixing with a benchmark perfluorinated surfactant, perfluorotetradecanoic acid (PF), is explored. The films exhibit nonideal mixing, as determined by surface pressure-area (π-A) isotherms and surface potential measurements, and phase-separation between the two components was observed by the direct visualization of the monolayers, and grazing-incident X-ray diffraction at the air-water interface. The pure and mixed films follow similar trends in the order of C18-0-C18 < PF < χPF = 0.50 mixed films for both their extent of hysteresis and their stability at the air-water interface. Further, crystallographic data for the mixed film emerge as a simple combination of distinct diffraction patterns characteristic of both the individual components, consistent with the other findings reported here and thus clarify the intermolecular behavior of the binary mixture at the surface.
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Membrane-binding proteins often associate with lipid membranes through a singular binding interface which is generally modeled as a two-state system: bound or unbound. However, even a single interface can engage with more than one mode of binding since a variety of interactions can contribute to the binding event. Unfortunately, the ability to clearly delineate the different binding modes of a singular binding interface has been elusive with existing models. Here, we present a study on milk fat globule EGF factor 8 (MFG-E8), which belongs to a class of proteins that identifies and binds phosphatidylserine (PS). These proteins detect membrane dysregulation implicated in exposed PS in apoptosis and malignant cells. In order to elucidate the factors affecting the binding of MFG-E8, we used a model system consisting of a series of lipid vesicles with varying PS mole fraction to identify the sensitivity of MFG-E8's binding affinity to changes in electrostatics using a tryptophan fluorescence spectral shift assay. Using a newly developed model, we experimentally identified three binding modes, each associated with a different number of PS lipids, with its cooperativity for binding being enhanced by the availability of negatively charged lipids. X-ray reflectivity experiments additionally suggest that MFG-E8's binding modes are influenced by membrane packing. The protocols established for elucidating MFG-E8's interaction with lipid membranes under different membrane conditions can be applied to the study of other membrane-binding proteins that target specific membrane attributes, such as fluidity and electrostatics, and help elucidate these membrane targeting mechanisms and their subsequent binding events.
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Proteínas de Transporte , Fosfatidilserinas , Fosfatidilserinas/metabolismo , Proteínas do Leite/metabolismoRESUMO
Employing small-angle X-ray scattering (SAXS), we explore the conditions under which assembly of gold nanoparticles (AuNPs) grafted with the thermosensitive polymer poly(N-isopropylacrylamide) (PNIPAM) emerges. We find that short-range order assembly emerges by combining the addition of electrolytes or polyelectrolytes with raising the temperature of the suspensions above the lower-critical solution temperature (LCST) of PNIPAM. Our results show that the longer the PNIPAM chain is, the better organization in the assembled clusters. Interestingly, without added electrolytes, there is no evidence of AuNPs assembly as a function of temperature, although untethered PNIPAM is known to undergo a coil-to-globule transition above its LCST. This study demonstrates another approach to assembling potential thermosensitive nanostructures for devices by leveraging the unique properties of PNIPAM.
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Two-dimensional materials have unusual properties and promise applications in nanoelectronics, spintronics, photonics, (electro)catalysis, separations, and elsewhere. Most are inorganic and their properties are difficult to tune. Here we report the preparation of Zn porphene, a member of the previously only hypothetical organic metalloporphene family. Similar to graphene, these also are fully conjugated two-dimensional polymers, but are composed of fused metalloporphyrin rings. Zn porphene is synthesized on water surface by two-dimensional oxidative polymerization of a Langmuir layer of Zn porphyrin with K2IrCl6, reminiscent of known one-dimensional polymerization of pyrroles. It is transferable to other substrates and bridges µm-sized pits. Contrary to previous theoretical predictions of metallic conductivity, it is a p-type semiconductor due to a predicted Peierls distortion of its unit cell from square to rectangular, analogous to the appearance of bond-length alternation in antiaromatic molecules. The observed reversible insertion of various metal ions, possibly carrying a fifth or sixth ligand, promises tunability and even patterning of circuits on an atomic canvas without removing any π centers from conjugation.
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Objective: To assess the impact of proton pump inhibitors (PPIs) on cardiovascular health and performance in elite athletes. This study aims to understand the utilization patterns, potential cardiovascular implications, and performance outcomes associated with PPI use in this specific population. Methods: A comprehensive review of PPI use among elite athletes was conducted, including a detailed analysis of medication type, dosage, frequency, and duration. The study involved a retrospective examination of medical and training records of athletes whoused PPIs in 2021. The analysis focused on evaluating the correlation between PPI use and cardiovascular health markers, as well as performance metrics in these athletes. Results: The study found a significant prevalence of PPI use among elite athletes, primarily for managing exercise-induced gastrointestinal symptoms. Key findings include: (1) a notable variation in the type and dosage of PPIs used; (2) a correlation between long-term PPI use and certain cardiovascular health markers; (3) athletes on PPIshad varied performance outcomes, with some showing decreased endurance. Conclusion: The study highlights the need for a more nuanced understanding of PPI use in elite athletes, emphasizing the importance of personalized medical guidance. While PPIs can bebeneficial for managing specific gastrointestinal issues in athletes, their impact on cardiovascular health and athletic s requires careful consideration and monitoring. This research underscores the necessity for developing tailored medication strategiesfor elite athletes to optimize health and performance outcomes (AU)
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Humanos , Bombas de Próton/farmacologia , Atletas , Desempenho Físico Funcional , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacosRESUMO
BACKGROUND: A high mortality rate has always been observed in patients with severe community-acquired pneumonia (SCAP) admitted to the intensive care unit (ICU); however, there are few reported predictive models regarding the prognosis of this group of patients. This study aimed to screen for risk factors and assign a useful nomogram to predict mortality in these patients. METHODS: As a developmental cohort, we used 455 patients with SCAP admitted to ICU. Logistic regression analyses were used to identify independent risk factors for death. A mortality prediction model was built based on statistically significant risk factors. Furthermore, the model was visualized using a nomogram. As a validation cohort, we used 88 patients with SCAP admitted to ICU of another hospital. The performance of the nomogram was evaluated by analysis of the area under the receiver operating characteristic (ROC) curve (AUC), calibration curve analysis, and decision curve analysis (DCA). RESULTS: Lymphocytes, PaO2/FiO2, shock, and APACHE II score were independent risk factors for in-hospital mortality in the development cohort. External validation results showed a C-index of 0.903 (95% CI 0.838-0.968). The AUC of model for the development cohort was 0.85, which was better than APACHE II score 0.795 and SOFA score 0.69. The AUC for the validation cohort was 0.893, which was better than APACHE II score 0.746 and SOFA score 0.742. Calibration curves for both cohorts showed agreement between predicted and actual probabilities. The results of the DCA curves for both cohorts indicated that the model had a high clinical application in comparison to APACHE II and SOFA scoring systems. CONCLUSIONS: We developed a predictive model based on lymphocytes, PaO2/FiO2, shock, and APACHE II scores to predict in-hospital mortality in patients with SCAP admitted to the ICU. The model has the potential to help physicians assess the prognosis of this group of patients.
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Infecções Comunitárias Adquiridas , Pneumonia , Síndrome do Desconforto Respiratório , Humanos , Mortalidade Hospitalar , Hospitais , Unidades de Terapia Intensiva , Fatores de RiscoRESUMO
The dried rhizome of Dioscorea nipponica Makino ("Chuanshanlong" in Chinese) is a medicinal herb with multiple major producing areas. The main objective of this study was the comparative profiling of Dioscoreae Nipponicae Rhizoma (DNR) from various geographical origins. A hypoxia/reoxygenation-induced H9c2 cell injury model was established, and the antimyocardial ischemia activity of DNR samples from different origins was detected using the cell counting kit-8 (CCK-8) method. The result showed that the antimyocardial ischemia potential of DNR samples from the Heilongjiang province was higher than that of the other studied samples. Subsequently, a plant metabolomics technique utilizing ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q TOF-MS) was used to determine the differences in DNR samples from various geographical origins. Forty compounds, including steroidal saponins, free fatty acids, and organic acids, were tentatively identified based on UPLC-Q TOF-MS fragmentation pathways and via comparison with available reference standards. Partial least squares discriminant analysis was performed to estimate the differences in DNR samples from different origins. Five compounds were significantly up-regulated and correlated with antimyocardial ischemia in DNR samples from Heilongjiang province. Molecular docking was used to discern the interactions of key markers with the active sites of the target protein. The findings signified that UPLC-Q TOF-MS metabolomics coupled with molecular docking is a powerful tool to rapidly identify the quality control characteristics of DNR samples and their products. The research provides a direction for the rational utilization of DNR.
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Dioscorea , Rizoma , Rizoma/química , Simulação de Acoplamento Molecular , Metabolômica , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodosRESUMO
OBJECTIVE: To investigate the effect of icariin on the transformation efficiency of germ cell-like cells from mouse induced pluripotent stem cells into sperm cells in vitro. METHODS: Firstly, mouse induced pluripotent stem cells were induced and cultured to transform into germ cell-like cells, and the primordial germ cell-like cells were identified by Western blot and RT-PCR. Then, different concentrations of icariin (0.1µg/mL, 1µg/mL, 10µg/mL and 100µg/mL) were added into the culture medium, and the obtained primitive germ cell-like cells were cultured, Western blot and RT-PCR were used to identify the obtained sperm cells, the transformation efficiency was compared. RESULTS: The primordium germ cell-like cells obtained from mouse induced pluripotent stem cells in vitro specially expressed Oct-4 protein, C-kit protein, Mvh mRNA, Fragilis mRNA and Stella mRNA. The sperm cells were specially expressed VASA, SCP3 and γH2AX proteins. RT-PCR showed that the sperm cells were specially expressed Ddx4, Tp2 and Prm1 mRNA. Compared with the control group, the expression level of VASA protein (1.744±0.283, 2.882±0.373, 6.489±0.460), SCP3 protein (2.250±0.306, 7.058±0.521, 8.654±0.804), γH2AX protein (4.304±0.433, 5.713±0.339, 9.268±0.545), Ddx4 mRNA (1.374±0.145, 2.846±0.194, 4.021±0.154), Tp2 mRNA (1.358±0.130, 3.623±0.326, 5.811±0.390) and Prm1 mRNA (1.326±0.162, 3.487±0.237, 4.666±0.307) in 0.1µg/mL, 1µg/mL, 10µg/mL icariin experimental groups were all lower than that of VASA protein (10.560±0.413), SCP3 protein (13.804±0.642), γH2AX protein (11.874±0.464), Ddx4 mRNA (6.4005±0.361), Tp2 mRNA (7.314±0.256) and Prm1 mRNA (7.334±0.390) in 100µg/mL icariin experimental group. CONCLUSIONS: Icariin can promote the transformation of mouse induced pluripotent stem cells into sperm cells in vitro, and it is concentration-dependent manner in a certain concentration range.
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Células-Tronco Pluripotentes Induzidas , Masculino , Animais , Camundongos , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular , Sêmen , Espermatozoides , RNA Mensageiro/metabolismoRESUMO
RO7449135, an anti-kallikrein (KLK)5/KLK7 bispecific antibody, is in development as a potential therapy against Netherton's syndrome (NS). In cynomolgus monkey studies, RO7449135 bound to KLK5 and KLK7, causing considerable accumulation of total KLKs, but with non-dose-proportional increase. To understand the complex PKPD, a population model with covariate analysis was developed accounting for target binding in skin and migration of bound targets from skin to blood. The covariate analysis suggested the animal batch as the categorical covariate impacting the different KLK5 synthesis rates between the repeat-dose study and single-dose study, and the dose as continuous covariate impacting the internalization rate of the binary and ternary complexes containing KLK7. To comprehend the mechanism underlying, we hypothesized that inhibition of KLK5 by RO7449135 prevented its cleavage of the pro-enzyme of KLK7 (pro-KLK7) and altered the proportion between pro-KLK7 and KLK7. Besides the pro-KLK7, RO7449135 can interact with other proteins like LEKTI through KLK7 connection in a dose-dependent manner. The different high-order complexes formed by RO7449135 interacting with pro-KLK7 or LEKTI-like proteins can be subject to faster internalization rate. Accounting for the dose and animal batch as covariates, the model-predicted free target suppression is well aligned with the visual target engagement check. The population PKPD model with covariate analysis provides the scientific input for the complex PKPD analysis, successfully predicts the target suppression in cynomolgus monkeys, and thereby can be used for the human dose projection of RO7449135.
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Anticorpos Biespecíficos , Calicreínas , Pele , Animais , Macaca fascicularis , Pele/metabolismo , Anticorpos Biespecíficos/farmacocinéticaRESUMO
BACKGROUND: Hereditary spastic paraplegia (HSP) is a group of neurogenetic diseases of the corticospinal tract, accompanied by distinct spasticity and weakness of the lower extremities. Mutations in the spastic paraplegia type 4 (SPG4) gene, encoding the spastin protein, are the major cause of the disease. This study reported a Chinese family with HSP caused by a novel mutation of the SPG4 gene. CASE SUMMARY: A 44-year-old male was admitted to our hospital for long-term right lower limb weakness, leg stiffness, and unstable walking. His symptoms gradually worsened, while no obvious muscle atrophy in the lower limbs was found. Neurological examinations revealed that the muscle strength of the lower limbs was normal, and knee reflex hyperreflexia and bilateral positive Babinski signs were detected. Members of his family also had the same symptoms. Using mutation analysis, a novel heterozygous duplication mutation, c.1053dupA, p. (Gln352Thrfs*15), was identified in the SPG4 gene in this family. CONCLUSION: A Chinese family with HSP had a novel mutation of the SPG4 gene, which is autosomal dominant and inherited as pure HSP. The age of onset, sex distribution, and clinical manifestations of all existing living patients in this family were analyzed. The findings may extend the current knowledge on the existing mutations in the SPG4 gene.
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During the solvent extraction of metal ions from an aqueous to an organic phase, organic-soluble extractants selectively target aqueous-soluble ions for transport into the organic phase. In the case of extractants that are also soluble in the aqueous phase, our recent studies of lanthanide ion-extractant complexes at the surface of aqueous solutions suggested that ion-extractant complexation in the aqueous phase can hinder the solvent extraction process. Here, we investigate a similar phenomenon relevant to the separation of Co(II), Ni(II), and Fe(III). X-ray fluorescence near total reflection and tensiometry are used to characterize ion adsorption behavior at the surface of aqueous solutions containing water-soluble extractants, either bis(2-ethylhexyl) phosphoric acid (HDEHP) or 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEHEHP), as well as adsorption to a monolayer of water-insoluble extractant dihexadecyl phosphoric acid (DHDP) at the aqueous-vapor interface. Competitive adsorption of Ni(II) and Fe(III) utilizing either HDEHP or DHDP illustrates the essential feature of the recent lanthanide studies that the ion, which is preferentially extracted in liquid-liquid extraction, Fe(III), is found preferentially adsorbed to the water-vapor interface only in the presence of the water-insoluble extractant DHDP. A more subtle competition produces comparable adsorption behavior of Co(II) and Ni(II) at the surfaces of both HDEHP- and HEHEHP-aqueous solutions in spite of the known preference for Co(II) under solvent extraction conditions. Comparison experiments with a monolayer of DHDP reveal that Co(II) is preferentially adsorbed to the surface. This preference for Co(II) is also supported by molecular dynamics simulations of the potential of mean force of ions interacting with the soluble extractants in water. These results highlight the possibility that complexation of extractants and ions in the aqueous phase can alter selectivity in the solvent extraction of critical elements.
RESUMO
Protein isoforms are structural variants with changes in the overall flexibility predominantly at the tertiary level. For membrane associated proteins, such structural flexibility or rigidity affects membrane stability by playing modulatory roles in lipid-protein interaction. Herein, we investigate the protein chain flexibility mediated changes in the mechanistic behavior of phospholipid model membranes in the presence of two well-known isoforms, erythroid (ER) and nonerythroid (NER) spectrin. We show dramatic alterations of membrane elasticity and stability induced by spectrin in the Langmuir monolayers of phosphatidylocholine (PC) and phosphatidylethanolamine (PE) by a combination of isobaric relaxation, surface pressure-area isotherm, X-ray scattering, and microscopy measurements. The NER spectrin drives all monolayers to possess an approximately equal stability, and that required 25-fold increase and 5-fold decrease of stability in PC and PE monolayers, respectively. The untilting transition of the PC membrane in the presence of NER spectrin observed in X-ray measurements can explain better membrane packing and stability.