Publications by authors named "Mei Yamaguchi"

Taste, especially unpleasant taste, can be key for patient compliance. In the formulation development process, drug-cyclodextrin (CD) inclusion complexes are often used to improve the solubility of a drug and/or mask its bitterness. This study aimed to evaluate the bitter masking effect of CDs on different drugs using NMR-ROESY analysis, human sensory tests, and e-tongue measurements.

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Here we report the synthesis of a zeolitic imidazolate framework with RHO topology (RHO-Zn(eim); eim is the deprotonated anion of 2-ethylimidazole (Heim)) in the aqueous phase. Zn(eim) crystals were prepared by the reaction between Heim and zinc acetate in deionized water. The products prepared at relatively high Heim/Zn molar ratios were Zn(eim) whose structure assigned to RHO, qtz and ANA topologies.

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Background: Respiratory viral infections are common and potentially devastating to patients with underlying lung disease. Diagnosing viral infections often requires invasive sampling, and interpretation often requires specialized laboratory equipment. Here, we test the hypothesis that a breath test could diagnose influenza and rhinovirus infections using an in vitro model of the human airway.

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Alloplasmic plants exhibit various phenotypic changes such as cytoplasmic male sterility (CMS). We have been attempting to produce an alloplasmic CMS line (2n = 20) carrying cytoplasm (cyt-) for several years, but a single extra chromosome always remained in all lines produced. We confirmed a -specific band in the alloplasmic line carrying cytoplasm by RAPD analysis, indicating that the additional chromosome was derived from .

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Monitoring plant volatile organic compound (VOC) profiles can reveal information regarding the health state of the plant, such as whether it is nutrient stressed or diseased. Typically, plant VOC sampling uses sampling enclosures. Enclosures require time and equipment which are not easily adapted to high throughput sampling in field environments.

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In social animals, scent secretions and marking behaviors play critical roles in communication, including intraspecific signals, such as identifying individuals and group membership, as well as interspecific signaling. Anal sacs are an important odor producing organ found across the carnivorans (species in the mammalian Order Carnivora). Secretions from the anal sac may be used as chemical signals by animals for behaviors ranging from defense to species recognition to signaling reproductive status.

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Volatile organic compound (VOC) emissions were measured from Chinese Hamster Ovary (CHO) cell and T cell bioreactor gas exhaust lines with the goal of non-invasively metabolically profiling the expansion process. Measurements of cellular 'breath' were made directly from the gas exhaust lines using polydimethylsiloxane (PDMS)-coated magnetic stir bars, which underwent subsequent thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) analysis. Baseline VOC profiles were observed from bioreactors filled with only liquid media.

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The respiratory system is continuously exposed to variety of biological and chemical irritants that contain reactive oxygen species, and these are well known to cause oxidative stress responses in lung epithelial cells. There is a clinical need to identify biomarkers of oxidative stress which could potentially support early indicators of disease and health management. To identify volatile biomarkers of oxidative stress, we analyzed the headspace above human bronchial epithelial cell cultures (HBE1) before and after hydrogen peroxide (HO) and cigarette smoke extract (CSE) exposure.

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The human respiratory tract releases volatile metabolites into exhaled breath that can be utilized for noninvasive health diagnostics. To understand the origin of this metabolic process, our group has previously analyzed the headspace above human epithelial cell cultures using solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). In the present work, we improve our model by employing sorbent-covered magnetic stir bars for headspace sorptive extraction (HSSE).

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Phytophthora ramorum is an invasive and devastating plant pathogen that causes sudden oak death in coastal forests in the western United States and ramorum blight in nursery ornamentals and native plants in various landscapes. As a broad host-range quarantine pest that can be asymptomatic in some hosts, P. ramorum presents significant challenges for regulatory efforts to detect and contain it, particularly in commercial nurseries.

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