Maleates

马来酸盐
  • 文章类型: Case Reports
    虽然建议母乳喂养,关于药物转移到人乳及其对哺乳婴儿的安全性的知识是有限的。以前只有一篇论文描述了两名患者在产后5个月和6个月时母乳喂养期间富马酸二甲酯(DMF)的转移,分别。当前的病例报告描述了富马酸单甲酯(MMF)的母体药代动力学数据,DMF的活性代谢产物,和婴儿产后3个月的MMF暴露估计。
    一名32岁的白人妇女开始使用DMF治疗(120毫克,2倍/天),用于产后3个月的多发性硬化症,在她的婴儿从母乳喂养断奶后。出生后第99天,患者在初始剂量治疗6天后24小时内收集了4份牛奶样本.此外,我们收集了一份母体血液样本,以计算牛奶-血浆(M/P)比.使用液相色谱与质谱联用方法分析样品。
    在人乳样品中观察到MMF的宽范围的测量的稳态浓度(5.5-83.5ng/mL)。MMF的估计每日婴儿剂量值,以150和200毫升/千克/天人乳摄入量计算,分别为5.76和7.68μg/kg/天,相对婴儿剂量为0.16%和0.22%。观察到的平均M/P比为0.059,类似于使用经验Koshimichi模型预测的M/P比(0.06)。
    将此病例报告与先前描述的两个病例相结合,估计婴儿暴露量很低,尽管有相关的患者内和患者间的变异性。研究应进一步关注婴儿暴露和安全性。
    UNASSIGNED: While breastfeeding is recommended, knowledge regarding medicine transfer to human milk and its safety for nursing infants is limited. Only one paper has previously described dimethyl fumarate (DMF) transfer during breastfeeding in two patients at 5 and 6 months postpartum, respectively. The current case report describes maternal pharmacokinetic data of monomethyl fumarate (MMF), the active metabolite of DMF, and infant exposure estimations of MMF at 3 months postpartum.
    UNASSIGNED: A 32-year-old Caucasian woman started DMF therapy (120 mg, 2x/day) for multiple sclerosis at 3 months postpartum, after weaning her infant from breastfeeding. On day 99 after birth, the patient collected four milk samples over 24 h after 6 days of treatment at the initial dose. Additionally, a single maternal blood sample was collected to calculate the milk-to-plasma (M/P) ratio. The samples were analyzed using liquid chromatography coupled with the mass spectrometry method.
    UNASSIGNED: A wide range of measured steady-state concentrations of MMF (5.5-83.5 ng/mL) was observed in human milk samples. Estimated daily infant dosage values for MMF, calculated with 150 and 200 mL/kg/day human milk intake, were 5.76 and 7.68 μg/kg/day, and the relative infant doses were 0.16 and 0.22%. The observed mean M/P ratio was 0.059, similar to the M/P ratio predicted using the empirical Koshimichi model (0.06).
    UNASSIGNED: Combining this case report with the two previously described cases, the estimated infant exposure is low, albeit with relevant intra- and inter-patient variabilities. Research should further focus on infant exposure and safety.
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  • 文章类型: Journal Article
    弱碱性药物的盐可以在制剂中部分解离,给予基本药物和反酸。本研究的目的是阐明物理化学性质对碱性药物-酸-聚合物相互作用和盐-聚合物混溶性的影响,并从分子水平解释其影响机制。选用6种不同理化性质的马来酸盐,以PVA为成膜材料。用多元线性回归分析了理化性质与混溶性之间的关系。通过XRD和拉曼成像确定制剂中盐的存在状态。通过NMR和XPS表征盐的稳定性。通过FTIR和NMR研究了分子间的相互作用。结果表明,盐与PVA的混溶性与盐的极性表面积和游离碱的Tg有关,代表氢键相互作用和溶解度势。碱性药物-酸-PVA分子间相互作用决定了三个分子的存在状态和键合模式。同时,配制后稳定性的降低增加了口腔分散膜中游离碱的数量,进而影响与PVA的混溶性。该研究为PVA基口腔分散膜的合理设计提供了参考。
    Salts of weakly basic drugs can partially dissociate in formulations, to give basic drugs and counter acids. The aim of the present study was to clarify the effect of physicochemical properties on the basic drug-acid-polymer interactions and salt-polymer miscibility, and to explain the influence mechanism at the molecular level. Six maleate salts with different physicochemical properties were selected and PVA was used as the film forming material. The relationship between the physicochemical properties and the miscibility was presented with multiple linear regression analysis. The existence state of salts in formulations were determined by XRD and Raman imaging. The stability of salts was characterized by NMR and XPS. The intermolecular interactions were investigated by FTIR and NMR. The results showed that the salt-PVA miscibility was related to polar surface area of salts and Tg of free bases, which represented hydrogen bond interaction and solubility potential. The basic drug-acid-PVA intermolecular interactions determined the existence state and bonding pattern of the three molecules. Meanwhile, the decrease of the stability after formulation increased the number of free bases in orodispersible films, which in turn affected the miscibility with PVA. The study provided references for the rational design of PVA based orodispersible films.
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  • 文章类型: Journal Article
    木质素,一种复杂结构难以分离的天然聚合物,在分离过程中容易发生C-C键缩合。为了减少木质素的凝结,在这里,提出了一种通过使用马来酸(MA)/臭氧(O3)的组合来分离小麦秸秆的新方法。木质素的去除,葡聚糖,木聚糖为38.07±0.2%,31.44±0.1%,和71.98±0.1%,分别,在小麦秸秆球磨6小时的条件下,反应温度60℃,和O3的保持时间为9分钟。在洗涤处理过的样品后,收集富含木质素的溶液以提取溶解的木质素(DL)。在MA/O3条件下获得的DL具有2.96mmol/g的羧基(-COOH)含量。MA的羧基与木质素γ位的羟基(-OH)进行酯化,O3在木质素侧链或酚环的位置反应,导致侧链的断裂和酚环的打开以引入羧基。2D-HSQC-NMR结果表明,在O3存在下木质素的酚开环反应基本上不含β-β和β-5缩合键。
    Lignin, a natural pol2ymer with a complex structure that is difficult to separate, is prone to C-C bond condensation during the separation process. To reduce the condensation of lignin, here, a novel method is proposed for separating the components by using a combination of maleic acid (MA)/ozone (O3) to co-treat wheat straw. The removal of lignin, glucan, and xylan was 38.07 ± 0.2%, 31.44 ± 0.1%, and 71.98 ± 0.1%, respectively, under the conditions of ball-milling of wheat straw for 6 h, reaction temperature of 60 °C, and O3 holding time of 9 min. Lignin-rich solutions were collected to extract the dissolved lignin (DL) after washing the treated samples. The DL obtained under MA/O3 conditions had a carboxyl group (-COOH) content of 2.96 mmol/g. The carboxyl group of MA underwent esterification with the hydroxyl group (-OH) at the γ position of lignin and O3 reacted on the positions of the lignin side chain or the phenolic ring, resulting in a break in the side chain and the opening of the phenolic ring to introduce the carboxyl group. The 2D-HSQC-NMR results revealed that the phenolic ring-opening reaction of lignin in the presence of O3 was essentially free of β-β and β-5 condensation bonds.
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  • 文章类型: Journal Article
    组胺H1受体(H1R)在过敏启动中起关键作用,并且需要设计以H1R为中心的高通量筛选方法以有效筛选新型配体。这项研究提出了一种采用苯乙烯马来酸(SMA)提取和His标签共价键合固定H1R膜蛋白的方法,最小化非特异性蛋白质干扰的干扰,同时保留天然蛋白质结构并最大化目标暴露。该方法用于开发用于高通量配体筛选的新材料,并在细胞膜色谱(CMC)中实施。建立了H1-His-SMALPs/CMC模型及其色谱性能(选择性,特异性和寿命)验证,与以前的CMC模型相比,寿命显着提高。随后,该模型有助于高通量筛选化合物库中的H1R配体,并初步验证潜在的H1R拮抗剂的活性.一种新型的H1R拮抗剂的鉴定为该领域的进一步发展奠定了基础。
    The histamine H1 receptor (H1R) plays a pivotal role in allergy initiation and undergoes the necessity of devising a high-throughput screening approach centered on H1R to screen novel ligands effectively. This study suggests a method employing styrene maleic acid (SMA) extraction and His-tag covalent bonding to immobilize H1R membrane proteins, minimizing the interference of nonspecific proteins interference while preserving native protein structure and maximizing target exposure. This approach was utilized to develop a novel material for high-throughput ligand screening and implemented in cell membrane chromatography (CMC). An H1R-His-SMALPs/CMC model was established and its chromatographic performance (selectivity, specificity and lifespan) validated, demonstrating a significant enhancement in lifespan compared to previous CMC models. Subsequently, this model facilitated high-throughput screening of H1R ligands in the compound library and preliminary activity verification of potential H1R antagonists. Identification of a novel H1R antagonist laid the foundation for further development in this area.
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  • 文章类型: Journal Article
    结构研究需要大量生产高纯度的靶蛋白。对于膜蛋白,决定它们结构的瓶颈是从细胞膜中提取靶蛋白。不适当地模拟感兴趣的蛋白质的疏水环境的去污剂也可以显著改变其结构。最近,使用含苯乙烯-马来酸(SMA)的脂质圆盘,共聚物成为膜蛋白纯化的有希望的策略。这里,我们详细描述了溶解在SMA中的钾离子通道的一步亲和纯化以及用于未来结构研究的样品制备。
    Structural studies require the production of target proteins in large quantities and with a high degree of purity. For membrane proteins, the bottleneck in determining their structure is the extraction of the target protein from the cell membranes. A detergent that improperly mimics the hydrophobic environment of the protein of interest can also significantly alter its structure. Recently, using lipodiscs with styrene-maleic acid (SMA), copolymers became a promising strategy for the purification of membrane proteins. Here, we describe in detail the one-step affinity purification of potassium ion channels solubilized in SMA and sample preparation for future structural studies.
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  • 文章类型: Journal Article
    在应用中扩展可穿戴智能设备的检测信息对其在日常生活和医疗保健中的使用具有实际意义。由机械损伤和连续使用引起的损坏和破损对于聚合物基质是不可避免的,因此预期将自修复性质赋予柔性传感器以延长其寿命和耐久性。此外,相对电阻变化与相对电阻变化的良好线性应变(应变系数,GF)有助于将电信号流线型转换为人体运动的3D信息,而现有的传感器工作忽视了信号的定量分析。这封信报告了一种可自我修复的柔性电子传感器,该传感器基于马来酸接枝天然橡胶(MNR)之间的氢键和静电相互作用,聚苯胺(PANI),和植酸(PA)。MNR是苯胺(ANI)聚合的柔性基质和模板,和PA充当掺杂剂和交联剂。MNR-PANI-PA传感器在室温下易于自我修复,增强的机械性能(~2.5兆帕,1000%应变),和良好的线性(GF在250%应变时为13.8,GF在250-100%应变时为32.0)。由于ΔR/R与弯曲角度之间的高度线性关系,人体肢体运动的电信号可以输出弯曲角度和频率的相关信息。通过构建传感阵列,还可以实时检测所施加的压力的位置和大小的变化。基于这些优势,MNR-PANI-PA复合传感器有望在健康监测中具有潜在的应用,身体运动检测,和电子皮肤。
    Expanding the detection information of wearable smart devices in applications has practical implications for their use in daily life and healthcare. Damage and breakage caused by mechanical injuries and continuous use are unavoidable for polymer matrices so self-healing properties are expected to be conferred on flexible sensors to extend their life and durability. In addition, a good linearity of relative resistance change vs. strain (gauge factor, GF) facilitates the streamlined conversion of electrical signals to 3D information of human motion, whereas existing works on sensors neglect the quantitative analysis of signals. This letter reports a self-healable flexible electronic sensor based on hydrogen bonding and electrostatic interaction between maleic acid-grafted natural rubber (MNR), polyaniline (PANI), and phytic acid (PA). MNR is the flexible matrix and the template for aniline (ANI) polymerization, and PA acts as the dopant and crosslinking agent. The MNR-PANI-PA sensor shows easy self-healing at room temperature, enhanced mechanical behaviour (∼2.5 MPa, 1000% strain), and excellent linearity (GF of 13.8 over 250% strain and GF of 32.0 over 250-100% strain). Due to the highly linear relationship between ΔR/R and bending angle, the electrical signals of human limb movement can output relevant information on bending angle and frequency. By constructing a sensing array, changes in the position and magnitude of applied pressure could also be detected in real-time. Based on these advantages, the MNR-PANI-PA composite sensor is expected to have potential applications in health monitoring, body motion detection, and electronic skins.
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  • 文章类型: Journal Article
    背景:圣多美和普林西比首次登革热暴发于2022年报告。进行了昆虫学调查,以建立伊蚊幼虫栖息地的类型,Ae的分布。埃及伊蚊和Ae.白纹,相关的昆虫学风险和Ae的易感性。埃及伊蚊杀虫剂,提供证据以告知疫情应对。
    结果:在2022年的旱季和雨季期间,对圣多美和普林西比的所有七个卫生区进行了昆虫学调查。使用胡椒基丁醚(PBO)和马来酸二乙酯(DEM)进行了WHO试管和增效剂测定,以及Ae中F1534C/V1016I/V410L突变的基因分型。埃及伊蚊.埃及伊蚊和埃。在该国所有七个卫生区中都发现了白纹伊蚊,其Ae含量很高。埃及伊蚊在最城市化的地区,阿瓜·格兰德.两种伊蚊主要在旧轮胎中繁殖,废弃的水箱和储水容器。在这两个调查期间,Breteau(BI>50),房屋(HI>35%)和集装箱(CI>20%)指数高于世卫组织设定的提示登革热传播潜在风险较高的阈值.Ae.取样的埃及伊蚊对所有测试的杀虫剂都敏感,除了二氯二苯基三氯乙烷(DDT)(9.2%的死亡率,抗性),bendiocarb(61.4%死亡率,抗性)和氯氰菊酯(97%死亡率,可能具有抗性)。在Ae中观察到完全恢复。在预暴露于增效剂PBO后,埃及伊蚊对苯迪威具有抗性。只有一个Ae。发现埃及伊蚊标本携带F1534C突变。
    结论:这些发现揭示了全年登革热传播的高潜在风险,大部分幼虫繁殖发生在旧轮胎中,储水和废弃的容器。大多数测试的杀虫剂仍然有效控制圣多美的伊蚊媒介,除了滴滴涕和苯迪奥克.这些数据强调了提高社区意识和实施常规登革热媒介控制策略以防止圣多美和普林西比进一步爆发的重要性,以及该次区域的其他地方。
    BACKGROUND: The first dengue outbreak in Sao Tome and Principe was reported in 2022. Entomological investigations were undertaken to establish the typology of Aedes larval habitats, the distribution of Ae. aegypti and Ae. albopictus, the related entomological risk and the susceptibility profile of Ae. aegypti to insecticides, to provide evidence to inform the outbreak response.
    RESULTS: Entomological surveys were performed in all seven health districts of Sao Tome and Principe during the dry and rainy seasons in 2022. WHO tube and synergist assays using piperonyl butoxide (PBO) and diethyl maleate (DEM) were carried out, together with genotyping of F1534C/V1016I/V410L mutations in Ae. aegypti. Aedes aegypti and Ae. albopictus were found in all seven health districts of the country with high abundance of Ae. aegypti in the most urbanised district, Agua Grande. Both Aedes species bred mainly in used tyres, discarded tanks and water storage containers. In both survey periods, the Breteau (BI > 50), house (HI > 35%) and container (CI > 20%) indices were higher than the thresholds established by WHO to indicate high potential risk of dengue transmission. The Ae. aegypti sampled were susceptible to all insecticides tested except dichlorodiphenyltrichloroethane (DDT) (9.2% mortality, resistant), bendiocarb (61.4% mortality, resistant) and alpha-cypermethrin (97% mortality, probable resistant). A full recovery was observed in Ae. aegypti resistant to bendiocarb after pre-exposure to synergist PBO. Only one Ae. aegypti specimen was found carrying F1534C mutation.
    CONCLUSIONS: These findings revealed a high potential risk for dengue transmission throughout the year, with the bulk of larval breeding occurring in used tyres, water storage and discarded containers. Most of the insecticides tested remain effective to control Aedes vectors in Sao Tome, except DDT and bendiocarb. These data underline the importance of raising community awareness and implementing routine dengue vector control strategies to prevent further outbreaks in Sao Tome and Principe, and elsewhere in the subregion.
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  • 文章类型: Journal Article
    氧化石墨烯(GO)膜的构建和改性,掺入与马来酸(MA)交联并由尼龙膜支撑的聚乙烯醇(PVA),已成功完成。进行PVA和MA浓度的系统变化,以实现具有良好特性的膜,稳定性,和优良的海水淡化性能。利用中央复合设计(CCD)的优化研究表明,使用10mLPVA(0.1mg。mL-1)和0.9M的MA(GO-MA0.9-PVA10/尼龙膜)。实验结果表明,PVA和MA的包含导致GO的层间距离增加和膜稳定性增强。PVA的加入增加了GO膜的亲水性,而MA的添加降低了膜的亲水性。GO-MA0.9-PVA10/尼龙膜表现出最高的脱盐性能,具有超过99.9%的拒收值和18.76kg的渗透。m-2.在50°C的温度下在1%NaCl进料下的h-1该膜在长达70小时的延长时间段内表现出一致的脱盐性能稳定性。此外,它表现出耐久性通过8个周期的24小时使用与洗涤处理。总之,GO-MA0.9-PVA10/尼龙膜强烈建议用于实际应用,基于对其稳定性和脱盐效率的综合评价,优于其他膜选项。
    The construction and modification of a Graphene Oxide (GO) membrane, incorporating polyvinyl alcohol (PVA) cross-linked with maleic acid (MA) and supported by a nylon membrane, have been successfully completed. Systematic variations in PVA and MA concentrations were conducted to achieve membranes with favorable characteristics, stability, and excellent desalination performance. Optimization studies utilizing the Central Composite Design (CCD) revealed that the most optimal desalination results were obtained with 10 mL of PVA (0.1 mg mL-1) and 0.9 M of MA (GO-MA0.9-PVA10/Nylon membrane). Experimental findings demonstrated that the inclusion of PVA and MA resulted in an increased interlayer distance of GO and enhanced membrane stability. The addition of PVA increases GO membrane hydrophilicity, while the addition of MA reduces membrane hydrophilicity. The GO-MA0.9-PVA10/Nylon membrane exhibited the highest desalination performance, boasting a rejection value exceeding >99.9% and a permeance of 18.76 kg m-2.h-1 under 1% NaCl feed at a temperature of 50 °C. This membrane demonstrated consistent desalination performance stability over an extended period of up to 70 h. Moreover, it exhibited durability through 8 cycles of 24-h usage with washing treatment. In conclusion, the GO-MA0.9-PVA10/Nylon membrane is strongly recommended for practical applications, outperforming other membrane options based on the comprehensive evaluation of its stability and desalination efficiency.
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  • 文章类型: Journal Article
    掺入淀粉,这是一种潜在的可生物降解的石油基聚合物替代品,由于加工性能的限制和所得到的材料的弱性能,因此在常规聚合物中加入是具有挑战性的。在这里,玉米淀粉/聚乙烯醇(PVA)共混膜(淀粉:PVA比例为50:50)通过溶剂流延法制备,使用甘油作为增塑剂并以不同浓度的马来酸作为交联剂。傅里叶变换红外光谱揭示了马来酸交联剂通过酯键与淀粉和PVA的聚合物网络的分子相互作用。膜的性质强烈依赖于马来酸浓度。增加的马来酸浓度赋予薄膜疏水性;因此,水膨胀显著减少,耐水性增强。含有20重量%马来酸的薄膜表现出优异的阻隔性能,最低的氧气和水蒸气透过率分别为0.5±0.2cc/m2·day和232.3±5.4g/m2·day,分别。此外,膜的力学性能随着交联度的增加而提高。该研究表明,马来酸的添加导致淀粉/PVA共混物膜的整体性能的改善。因此,马来酸交联膜可用作食品包装应用中的阻隔材料。
    Incorporating starch, which is a potential biodegradable substitute for petroleum-based polymers, into conventional polymers is challenging owing to limitations in processability and weak-performing resulting materials. Herein, corn starch/polyvinyl alcohol (PVA) blend films (starch: PVA ratio of 50:50) were prepared via the solvent casting method using glycerol as a plasticizer and with varying concentrations of maleic acid as the crosslinking agent. Fourier transform infrared spectroscopy revealed the molecular interactions of the maleic acid crosslinker with the polymeric network of starch and PVA through an ester linkage. The properties of the films were strongly dependent on the maleic acid concentration. An increasing maleic acid concentration imparted hydrophobicity to the film; therefore, water swelling was significantly reduced, and water resistance was enhanced. The film containing 20 wt% maleic acid exhibited excellent barrier properties, with the lowest oxygen and water vapor transmission rates of 0.5 ± 0.2 cc/m2⋅day and 232.3 ± 5.4 g/m2⋅day, respectively. Moreover, the mechanical properties of the film improved with increasing crosslinking. This study demonstrates that the addition of maleic acid leads to an improvement in the overall performance of starch/PVA blend films. Therefore, maleic acid-crosslinked films can be used as barrier materials in food packaging applications.
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  • 文章类型: Journal Article
    我们报道了pH调节剂作为片剂配方中歧化阻滞剂的新用途。感兴趣的药物分子具有需要溶解度增强的显著的生物利用度挑战。除了有限的盐/共晶选项,潜在盐的歧化被确定为实质性风险。在专门设计的应力测试中,使用拉曼光谱与化学计量学和定量X射线衍射相结合,我们调查了不成比例现象。从晶体学中汲取的经验和见解推动了马来酸盐形式作为目标API的选择。受富马酸盐形式独特的稳定性和溶解度特性的启发,我们使用富马酸作为微环境pH调节剂。高风险(HCl)和中等风险(马来酸盐)方案的概念验证实验证实了富马酸的协同优势,它与歧化释放的游离碱相互作用,形成更易溶的物种。所得的半富马酸盐有助于将溶解度保持在升高的水平。这项工作展示了一种创新的技术,可以使用药典赋形剂在药物吸收的“降落伞”阶段调节溶解度下降,这种方法可以作为盐歧化的有效风险缓解策略。
    We report a novel utilization of a pH modifier as a disproportionation retardant in a tablet formulation. The drug molecule of interest has significant bioavailability challenges that require solubility enhancement. In addition to limited salt/cocrystal options, disproportionation of the potential salt(s) was identified as a substantial risk. Using a combination of Raman spectroscopy with chemometrics and quantitative X-ray diffraction in specially designed stress testing, we investigated the disproportionation phenomena. The learnings and insight drawn from crystallography drove the selection of the maleate form as the target API. Inspired by the fumarate form\'s unique stability and solubility characteristics, we used fumaric acid as the microenvironmental pH modulator. Proof-of-concept experiments with high-risk (HCl) and moderate-risk (maleate) scenarios confirmed the synergistic advantage of fumaric acid, which interacts with the freebase released by disproportionation to form a more soluble species. The resultant hemifumarate helps maintain the solubility at an elevated level. This work demonstrates an innovative technique to mediate the solubility drop during the \"parachute\" phase of drug absorption using compendial excipients, and this approach can potentially serve as an effective risk-mitigating strategy for salt disproportionation.
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