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1.
Xiao-Lei Qiu Zi-Rui Fan Yang-Yang Liu Ding-Fu Wang Shi-Xin Wang Chun-Xia Li 《International journal of molecular sciences》2021,22(8)
A self-nanoemulsifying drug delivery system (SNEDDS) was developed to enhance the absorption of heparin after oral administration, in which heparin was compounded with phospholipids to achieve better fat solubility in the form of heparin-phospholipid (HEP-Pc) complex. HEP-Pc complex was prepared using the solvent evaporation method, which increased the solubility of heparin in n-octanol. The successful preparation of HEP-Pc complex was confirmed by differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, NMR, and SEM. A heparin lipid microemulsion (HEP-LM) was prepared by high-pressure homogenization and characterized. HEP-LM can enhance the absorption of heparin after oral administration, significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT) in mice, and reduce fibrinogen (FIB) content. All these outcomes indicate that HEP-LM has great potential as an oral heparin formulation. 相似文献
2.
Hyun Sun Choi Yun Kee Jo Gwang-Noh Ahn Kye Il Joo Dong-Pyo Kim Hyung Joon Cha 《Advanced functional materials》2021,31(46):2104602
The esophagus is a tubular-shaped muscular organ where swallowed fluids and muscular contractions constitute a highly dynamic environment. The turbulent, coordinated processes that occur through the oropharyngeal conduit can often compromise targeted administration of therapeutic drugs to a lesion, significantly reducing therapeutic efficacy. Here, magnetically guidable drug vehicles capable of strongly adhering to target sites using a bioengineered mussel adhesive protein (MAP) to achieve localized delivery of therapeutic drugs against the hydrodynamic physiological conditions are proposed. A suite of highly uniform microparticles embedded with iron oxide (IO) nanoparticles (MAP@IO MPs) is microfluidically fabricated using the genipin-mediated covalent cross-linking of bioengineered MAP. The MAP@IO MPs are successfully targeted to a specific region and prolongedly retained in the tubular-structured passageway. In particular, orally administered MAP@IO MPs are effectively captured in the esophagus in vivo in a magnetically guidable manner. Moreover, doxorubicin (DOX)-loaded MAP@IO MPs exhibit a sustainable DOX release profile, effective anticancer therapeutic activity, and excellent biocompatibility. Thus, the magnetically guidable locomotion and robust underwater adhesive properties of the proteinaceous soft microbots can provide an intelligent modular approach for targeted locoregional therapeutics delivery to a specific lesion site in dynamic fluid-associated tubular organs such as the esophagus. 相似文献
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We used scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to observe the oral organelle, cytopharynx, and subpellicular structure of a Dileptus sp. The main results were as follows: (a) the cytostome was located on the ventral surface of the base of the beak, surrounded by a periportal matrix that integrated 135 microtube bundles. When these microtube bundles contract, radially arranged into a disk, the cytostome was closed. When these microtube bundles were stretch, they fell into the cytostome and opens. The diameter of the cytostome was about 16 μm regardless of its closure or opening, indicating that the contraction or elongation of these microtube bundles did not change the size of the cytostome, which was only related to whether it blocked the cytostome, thus determining the opening and closing of the cytostome. There were many microtube bundles on two sides of the feeding trough, which could widen or narrow the feeding trough and facilitate beak feeding. (b) The cytopharynx was basket‐like without a bottom with a diameter of about 6 μm and was woven from two kind fibers about 0.08 and 0.19 μm. (c) There were two types of extrusomes under the pellicle. Using transmission electron microscopy,the Type I extrusomes showed narrow and long egg shape, its cross section was circular which is composed by various electronic density of concentric. Using the scanning electron microscope, they were two slightly thin clavate, the length was about 5 μm, the diameter of the middle section was about 0.75 μm, and the diameter of the two ends was about 0.32 μm, they were distributed abundantly between the microtubule fasciculi which were located on both sides of the gap on the feeding groove. Using transmission electron microscopy, the Type II extrusomes showed egg shape. Using the scanning electron microscopy, they were about 1.6 × 0.8 μm in size, they were distributed abundantly under the body pellicle while rarely the proboscis. In addition, many different of developmental stages two types of extrusomes could be also seen in the cytoplasm. (d) There were very well‐developed fibrous systems under the pellicle that were woven from fibers about 0.14 μm in diameter that attached to the pellicle and bound some organelles in the cytoplasm (e.g., mitochondria, extrusomes) and other structures to the cytoplasm and maintained cell morphology. The results of this study not only supplement and enrich the morphological contents of the Dileptus sp., but also provide the basis for the study of the taxonomy of the Dileptus sp. It also provides a new method for researchers to explore the morphology and structure of ciliate cells under the cortex by SEM. 相似文献
4.
M. R. Thompson 《Drug development and industrial pharmacy》2015,41(8):1223-1231
Twin screw granulation (TSG) is a new process of interest to the pharmaceutical community that can continuously wet granulate powders, doing so at lower liquid concentrations and with better product consistency than found by a high shear batch mixer. A considerable body of research has evolved over the short time since this process was introduced but generally with little comparison of results. A certain degree of confidence has been developed through these studies related to how process variables and many attributes of machinery configuration will affect granulation but some major challenges still lay ahead related to scalability, variations in the processing regimes related to degree of channel fill and the impact of wetting and granulation of complex powder formulations. This review examines the current literature for wet granulation processes studied in twin screw extrusion machinery, summarizing the influences of operational and system parameters affecting granule properties as well as strives to provide some practical observations to newly interested users of the technique. 相似文献
5.
Health information technology (IT) is a promising way to achieve safer medication management in the delivery of healthcare. However, human factors/ergonomics dictates that in order to make the complex, cognitive work of healthcare delivery safer, health IT must properly support human cognition. This means, for example, that new health IT must reduce, not increase, workload during safety-critical tasks. The present study was the first to quantitatively assess the short- and long-term impact of bar coded medication administration (BCMA) IT on nurses' mental workload as well as on perceived medication safety. One-hundred seventy registered nurses across 3 dissimilar clinical units at an academic, freestanding pediatric hospital in the Midwest US participated in surveys administered before, 3 months after, and 12 months after the hospital implemented BCMA. Nurses rated their external mental workload (interruptions, divided attention, being rushed) and internal mental workload (concentration, mental effort) during medication administration tasks as well as the likelihood of each of three medication safety events: medication administration errors, medication errors on the clinical unit, and clinical unit-level adverse drug events. Clinical unit differences were assessed. Findings generally confirmed the hypothesis that external but not internal mental workload was associated with the perceived likelihood of a medication safety event. Comparisons of mental workload from pre- to post-BCMA revealed statistically significant changes in the critical care unit only. Medication safety appeared to improve over the long term in the hematology/oncology unit only. In the critical care and medical/surgical units, medication safety exhibited short-term improvements that were eliminated over time. Changes in mental workload and medication safety, two classically microergonomic constructs, were deeply embedded in macroergonomic phenomena. These included the fit between the BCMA system and the nature of nursing work, the process of BCMA implementation, and BCMA interactions with concurrent changes occurring in the hospital. Findings raise questions about achieving sustainable performance improvement with health IT as well as the balance between micro- and macroergonomic approaches to studying technology change.Relevance to industryDesigners must consider how technology changes cognitive work, including mental workload. Hospitals and other implementers of technology must ensure that new technology fits its users, their tasks, and the context of use, which may entail tailoring implementation, for example, to specific clinical units. Evaluators must look over time to assess both changes in cognitive work and implementation issues. Healthcare practitioners must also recognize that new technology means a complex transformation to an already complex sociotechnical system, which calls for a macroergonomic approach to design and analysis. 相似文献
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论述了负压法(射流法)回收治理液氨尾气的环保安全工艺技术、原理;解决了目前一直沿用的正压法无法解决的棘手问题。 相似文献
10.
Cocaine lowers brain reward thresholds, reflecting increased brain reward function. The authors investigated whether, similar to acute cocaine administration, cocaine-predictive conditioned stimuli would lower intracranial self-stimulation (ICSS) thresholds. Rats received a saline injection for 5 days, a cocaine injection (10 mg/kg) for 20 consecutive days, then saline for 5 additional days. Thresholds were measured immediately before and 10 min after each injection. The initial 5 saline injections had no effect on thresholds, whereas cocaine significantly lowered thresholds for 20 days. There was no tolerance or sensitization to this effect of cocaine over days. During the last 5 days when cocaine administration was substituted with saline, rats demonstrated a conditioned lowering of thresholds during the 2nd daily ICSS session. These data demonstrate that cocaine-predictive conditioned stimuli induce a conditioned facilitation of brain reward function. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献