A Novel Rapid Artificial Drying Schedule for Japanese Cedar Boards Retaining Natural Durability

Because Japanese cedar pollen (JCP) contains beta-1,3-d-glucan (BG), there is concern that its lingering presence in the atmosphere, especially during its scattering period, may cause false positives in the factor-G-based Limulus amebocyte lysate (LAL) assay used to test for deep mycosis (i.e., G-test). Hence, we examined whether the LAL assay would react positively with substances contained in JCP by using the G-test to measure JCP particles and extracts. BG was purified from the JCP extract on a BG-specific affinity column, and the percentage extractability was measured using three different BG-specific quantitative methods. The G-test detected 0.4 pg BG in a single JCP particle and 10 fg from a single particle in the extract. The percentage extractability of JCP-derived BG was not significantly different among the three quantitative methods. As the JCP particles should technically have been removed during serum separation, they should be less likely to be a direct false-positive factor. However, given that the LAL-assay-positive substances in the JCP extract were not distinguishable by the three BG-specific quantitative methods, we conclude that they may cause the background to rise. Therefore, in Japan false positives arising from JCP contamination should be considered when testing patients for deep mycosis.

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Experimental study of lateral resistance of bolted joints using Japanese cedar (Cryptomeria japonica) treated with resin impregnation

Journal of Wood Science ◽

10.1186/s10086-020-01918-8 ◽

2020 ◽

Vol 66 (1) ◽

Author(s):

Keita Ogawa ◽

Satoshi Fukuta ◽

Kenji Kobayashi

Keyword(s):

Short Pulse ◽

Japanese Cedar ◽

Bolted Joints ◽

Bolted Joint ◽

Yield Load ◽

Short Pulse Laser ◽

Resin Impregnation ◽

Lateral Resistance ◽

Ultraviolet Wavelength ◽

Resistance Performance

Abstract The development of wooden joints possessing high resistance performance has become an important issue for the construction of newer buildings. This study attempts to strengthen the lateral resistance of bolted joints using the previously reported plasticizing technique. This technique consists of two processing stages: incising the surface of the wood using an ultraviolet wavelength short-pulse laser and impregnating the resin into the incised area. This technique makes it possible to plasticize only a local part of the wood surface. Bolted joint specimens were assembled using plasticized wood around the bolt hole, and the lateral tests were conducted. Acrylic monomer and urethane prepolymer were used as the impregnating resins and their incision depths were set as 4 and 10 mm. When the lateral load acted parallel to the grain, changes in the lateral resistance characteristics were observed, especially for the stiffness and yield load. For example, when acryl was used, and the incision depth was 10 mm, an increment of 73% in the yield load was observed, as compared to the non-impregnated specimens. The specimen groups impregnated with acryl exhibited greater changes in their properties than those using urethane. When loaded perpendicular to the grain, an increase in properties were observed; however, these increments were lower than those of the groups loaded parallel to the grain.

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Unraveling the natural durability of wood: revealing the impact of decay-influencing characteristics other than fungicidal components

Holzforschung ◽

10.1515/hf-2020-0109 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Liselotte De Ligne ◽

Jan Van den Bulcke ◽

Jan M. Baetens ◽

Bernard De Baets ◽

Gang Wang ◽

...

Keyword(s):

Wood Species ◽

Prunus Avium ◽

Brown Rot ◽

Natural Durability ◽

Anatomical Features ◽

Brown Rot Fungi ◽

Material Characteristics ◽

The One ◽

Block Test ◽

The Impact

AbstractThe effect of fungicidal components in wood has been known for ages, yet there is no method to assess the impact of such components on the durability of a wood species, as compared to other material characteristics that influence decay. In this paper, the importance of fungicidal effects on the natural durability of 10 wood species is assessed in relation to other decay-influencing factors with a new test, the so-called ‘paste test’. By comparing results from this test with the ‘mini-block test’, on both heartwood and leached sapwood, insight is gained into the significance of fungicidal components on the one hand and other material characteristics on the other hand. The durability of species such as Prunus avium was attributed mainly to fungicidal components. For species such as Pterocarpus soyauxii, durability seemed to be an effect of both fungicidal components and moisture-regulating components, while the latter seemed to be of main importance in regulating the decay of Aucoumea klaineana and Entandrophragma cylindricum. Wood-anatomical features, such as the parenchyma content (in case of brown rot fungi) and the vessel-fiber ratio, possibly affect degradation as well. This work shows that fungicidal components are not always of major importance for the durability of a wood species. The authors hereby emphasize the importance of moisture-regulating components and wood anatomy on the durability of wood.

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Regulation of the Expression of SARS-CoV-2 Receptor Angiotensin-Converting Enzyme 2 in Nasal Mucosa

American Journal of Rhinology and Allergy ◽

10.1177/19458924211027798 ◽

2021 ◽

pp. 194589242110277

Author(s):

Tetsuji Takabayashi ◽

Kanako Yoshida ◽

Yoshimasa Imoto ◽

Robert P. Schleimer ◽

Shigeharu Fujieda

Keyword(s):

Epithelial Cells ◽

Angiotensin Converting Enzyme ◽

Nasal Mucosa ◽

Japanese Cedar ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Converting Enzyme ◽

Angiotensin Converting Enzyme 2 ◽

Japanese Cedar Pollen ◽

Cedar Pollen

Background Coronavirus disease 2019 (COVID-19) has caused a global pandemic. Higher expression of the virus receptor angiotensin-converting enzyme 2 (ACE2) in the nasal mucosa may be associated with high transmissibility and asymptomatic infection. In COVID-19, the elucidation of the determinants of ACE2 expression at nasal tissue level is crucial. The development of strategies to downregulate ACE2 expression in nasal epithelial cells might reduce transmission and be useful as a novel therapeutic approach. Objective To verify ACE2 expression in the nasal mucosa of patients with seasonal allergic rhinitis induced by Japanese cedar pollen (SAR-JCP) and chronic rhinosinusitis with nasal polyp (CRSwNP) and to examine the effects of short-chain fatty acids (SCFAs) on ACE2 expression in airway epithelial cells. Methods We assessed ACE2 expression in the nasal mucosa of control subjects, patients with SAR-JCP, and those with CRSwNP using real-time polymerase chain reaction. We also quantified ACE2 gene expression in cultured airway epithelial cells. Results Although ACE2 expression was greatly increased in a few patients with SAR-JCP during the Japanese cedar pollen season, mean levels were not significantly increased. ACE2 mRNA expression was significantly decreased in nasal polyp tissue from patients with chronic rhinosinusitis compared with the expression in that from control subjects. SCFAs generated by gastrointestinal microbiota significantly reduced resting ACE2 expression in cultured airway epithelial cells. SCFAs also significantly suppressed the dsRNA-dependent upregulation of ACE2 expression in airway epithelial cells. Conclusion Inflammatory endotype affects ACE2 expression in the nasal mucosa and influences susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In particular, type 2 inflammation could downregulate ACE2 expression in the nasal mucosa and reduces susceptibility to SARS-CoV-2 in patients with CRSwNP. Although in vivo experiments are required, administration of SCFAs to the nasal cavity might be worthy of consideration as a preventative or therapeutic strategy for the early-stage COVID-19.

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