Maintenance of species boundaries amid hybridization in two island gingers with similar ecological niches.

Understanding species boundaries maintenance in the face of hybridization/introgression is an intriguing yet complex topic in evolutionary biology. The underlying mechanisms, however, remain elusive. To address this, we propose to investigate the role of climatic shifts in shaping genetic structure and influencing species boundaries. We combine multilocus genetic data and species distribution modeling to explore how past and current climatic shifts affect the genetic structure and demographic history of two Taiwan endemic gingers, Zingiber pleiostachyum and Z. shuanglongense. We identified a well-delimited genetic structure with evidence of admixture, indicating incomplete reproductive isolation between the two gingers. This is likely due to secondary contact and range overlap during the last glacial maximum, leading to sporadic instances of hybridization. Niche overlap tests based on climate and soil data indicate that these two gingers occupy similar but nonidentical ecological niches. Furthermore, we found that the considerable differences in their current geographic distribution and altitude preferences might have resulted from different seed dispersal capabilities and competitive exclusion due to their similar niche preferences. Our results reveal a model where altitudinal differentiation and dispersal strategy synergistically reinforce the species divergence, thereby illuminating the importance of these factors in shaping and maintaining the island's biodiversity.

Tai Chi Chuan Exercise Improves Lung Function and Asthma Control through Immune Regulation in Childhood Asthma.

BACKGROUND: Tai Chi Chuan (TCC) is an exercise of low to moderate intensity with key features of mindfulness, structural alignment, and flexibility to relax the body and mind in adults. Our previous study showed that TCC could improve the quality of life (QoL), pulmonary function, and fractional exhaled nitric oxide in asthmatic children. We further investigated whether the benefits induced by TCC were associated with immune regulation. METHOD: Six- to twelve-year-old children diagnosed with mild to severe persistent asthma for at least one year according to the Global Initiative for Asthma guidelines were enrolled from a tertiary pediatric allergy center in Taiwan. Asthmatic children were divided into two groups based on their choice: (1) the TCC group had a 60-minute TCC exercise session once weekly led by an instructor and (2) the control group kept their original activity levels. All other exercises were encouraged as usual. Pulmonary function tests, laboratory tests, standardized pediatric asthma QoL questionnaire (PAQLQ(S)), and childhood asthma control test (C-ACT) were performed before and after the TCC program (12 weeks). Data on medications and exacerbations were collected from medical records. RESULTS: There were no differences between the TCC (n = 25) and control (n = 15) groups at baseline, except that the C-ACT showed significantly lower results in the TCC group (p=0.045). After 12 weeks, the number of leukocytes (p=0.041) and eosinophils (p=0.022) decreased, while regulatory T cells increased significantly (p=0.008) only in the TCC group. Lung functions (FEV1 and PEFR) were significantly improved in both the TCC (p < 0.001) and control (p=0.045 and 0.019, respectively) groups, while the PAQLQ(S) and C-ACT (p < 0.001) showed improvement only in the TCC group. Moreover, compared to the control group, the exacerbations within 12 weeks after the study were significantly decreased in the TCC group (p=0.031). After multiple regression by a conditional forward method, the factors that were significantly associated with exacerbation within 12 weeks after study is the practice of TCC and exacerbation within 24 weeks before study (p=0.013 and 0.015, respectively) after adjusting for age, sex, asthma severity, PEF, FEV1, C-ACT, PAQLQ(S), and medication score at baseline. CONCLUSION: TCC exercise may improve pulmonary functions, asthma control, and QoL and prevent exacerbations in asthmatic children through immune regulation. Further research on detailed mechanisms is mandated.

Comparative transcriptome analysis of the invasive weed Mikania micrantha with its native congeners provides insights into genetic basis underlying successful invasion.

BACKGROUND: Mikania micrantha H.B.K. (Asteraceae) is one of the world's most invasive weeds which has been rapidly expanding in tropical Asia, including China, while its close relative M. cordata, the only Mikania species native to China, shows no harm to the local ecosystems. These two species are very similar in morphology but differ remarkably in several ecological and physiological traits, representing an ideal system for comparative analysis to investigate the genetic basis underlying invasion success. In this study, we performed RNA-sequencing on the invader M. micrantha and its native congener M. cordata in China, to unravel the genetic basis underlying the strong invasiveness of M. micrantha. For a more robust comparison, another non-invasive congener M. cordifolia was also sequenced and compared. RESULTS: A total of 52,179, 55,835, and 52,983 unigenes were obtained for M. micrantha, M. cordata, and M. cordifolia, respectively. Phylogenetic analyses and divergence time dating revealed a relatively recent split between M. micrantha and M. cordata, i.e., approximately 4.81 million years ago (MYA), after their divergence with M. cordifolia (8.70 MYA). Gene ontology classifications, pathway assignments and differential expression analysis revealed higher representation or significant up-regulation of genes associated with photosynthesis, energy metabolism, protein modification and stress response in M. micrantha than in M. cordata or M. cordifolia. Analysis of accelerated evolution and positive selection also suggested the importance of these related genes and processes to the adaptability and invasiveness of M. micrantha. Particularly, most (77 out of 112, i.e. 68.75%) positively selected genes found in M. micrantha could be classified into four groups, i.e., energy acquisition and utilization (10 genes), growth and reproduction (13 genes), protection and repair (34 genes), and signal transduction and expression regulation (20 genes), which may have contributed to the high adaptability of M. micrantha to various new environments and the capability to occupy a wider niche, reflected in its high invasiveness. CONCLUSIONS: We characterized the transcriptomes of the invasive species M. micrantha and its non-invasive congeners, M. cordata and M. cordifolia. A comparison of their transcriptomes provided insights into the genetic basis of the high invasiveness of M. micrantha.

Composition and antifungal activities of the leaf essential oil of Neolitsea parvigemma from Taiwan.

The hydrodistillated leaf essential oil of Neolitsea parvigemma was analyzed to determine its composition and yield. Sixty-two compounds were identified, the main components being beta-caryophyllene (14.2%), beta-eudesmol (12.9%), alpha-cadinol (10.2%) and tau-cadinol (8.8%). Oxygenated sesquiterpenes (48.9%) and sesquiterpene hydrocarbons (48.8%) were the predominant groups of compounds. The antifungal indexes of the leaf oil against the 7 fungi, Aspergillus clavatus, A. niger, Chaetomium globosum, Cladosporium cladosporioides, Myrothecium verrucaria, Penicillium citrinum and Trichoderma viride, were 100.0, 72.3, 100.0, 100.0, 100.0, 75.8 and 88.6% at a 1 mg/mL concentration, respectively. The oil also exhibited anti-wood-decay-fungi activity against Trametes versicolor, Phaneochaete chrysosporium, Phaeolus schweintizii, and Lenzites sulphureu with MIC values of 50, 50, 25 and 25 microg/mL, respectively. For the antifungal and anti-wood-decay fungal activities of the oil, the active source compounds were determined to be alpha-cadinol, beta-eudesmol and tau-cadinol.

Honokiol inhibits LPS-induced maturation and inflammatory response of human monocyte-derived dendritic cells.

Honokiol (HNK) is a phenolic compound isolated from the bark of houpu (Magnolia officinalis), a plant widely used in traditional Chinese and Japanese medicine. While substantial evidence indicates that HNK possesses anti-inflammatory activity, its effect on dendritic cells (DCs) during the inflammatory reaction remains unclear. The present study investigates how HNK affects lipopolysaccharide (LPS)-stimulated human monocyte-derived DCs. Our experimental results show that HNK inhibits the inflammatory response of LPS-induced DCs by (1) suppressing the expression of CD11c, CD40, CD80, CD83, CD86, and MHC-II on LPS-activated DCs, (2) reducing the production of TNF-α, IL-1ß, IL-6, and IL-12p70 but increasing the production of IL-10 and TGF-ß1 by LPS-activated DCs, (3) inhibiting the LPS-induced DC-elicited allogeneic T-cell proliferation, and (4) shifting the LPS-induced DC-driven Th1 response toward a Th2 response. Further, our results show that HNK inhibits the phosphorylation levels of ERK1/2, p38, JNK1/2, IKKα, and IκBα in LPS-activated DCs. Collectively, the findings show that the anti-inflammatory actions of HNK on LPS-induced DCs are associated with the NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways.

Composition, antioxidant and antimicrobial activities of the seed essential oil of Calocedrus formosana from Taiwan.

The hydrodistillated seed essential oil of Calocedrus formosana was analyzed to determine its composition and yield. Twenty-seven compounds were identified, the main ones being alpha-pinene (63.8%), totarol (9.9%) and ferruginol (8.9%). Monoterpene hydrocarbons (73.5%) and oxygenated diterpenes (18.8%) were the predominant groups of compounds. The seed essential oil exhibited excellent antioxidant, antimicrobial and anti-wood-decay fungal activities.

Composition and antimicrobial activities of the leaf essential oil of Machilus kusanoi from Taiwan.

The hydrodistillated leaf essential oil of Machilus kusanoi was analyzed to determine its composition and yield. Twenty-three compounds were identified, the main components being beta-caryophyllene (23.3%), beta-eudesmol (17.1%), alpha-terpineol (16.0%), n-dodecanal (14.2%), and n-decanal (10.4%). Sesquiterpene hydrocarbons (28.1%) and non-terpenoids (25.0%) were the predominant groups of compounds. The leaf oil exhibited excellent antimicrobial and anti-wood-decay fungal activities.

Composition and antimicrobial activity of the leaf and twig oils of Litsea acutivena from Taiwan.

The chemical composition, and antimicrobial and anti-wood-decay fungal activities of the essential oils isolated from the leaves and twigs of Litsea acutivena of Taiwan were investigated. The essential oils from the fresh leaves and twigs were isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. Ninety-five and fifty-two compounds were identified in the leaf and twig oils, respectively. The main components of the leaf oil were gamma-patchoulene (11.0%), delta-cadinene (6.3%), trans-muurola-3,5-diene (5.9%), and beta-selinene (5.3%), whereas the main components of the twig oil were tau-cadinol (13.1%), beta-selinene (9.6%), trans-beta-ocimene (6.2%) and alpha-cadinol (7.7%). Bioactivity studies demonstrated that twig oil had excellent antimicrobial and anti-wood-decay fungal activities, superior to those of the leaf oil. For the antimicrobial and anti-wood-decay fungal activities of the twig oil, the active compounds were determined to be tau-cadinol and alpha-cadinol.

Composition and antifungal activities of the leaf essential oil of Litsea coreana from Taiwan.

The hydrodistilled leaf essential oil of Litsea coreana was analyzed by GC/FID and GC/MS. Fifty-two compounds were identified, the main components being n-decanal (27.5%), 2E,6E-farnesol (25.8%), beta-eudesmol (10.3%), ethyl n-dodecanoate (8.0%) and tau-cadinol (6.6%). Oxygenated sesquiterpenes (56.8%) and non-terpenoids (37.0%) were the predominant groups of compounds. The leaf oil exhibited excellent antifungal and anti-wood-decay fungal activities.

Osthole regulates inflammatory mediator expression through modulating NF-κB, mitogen-activated protein kinases, protein kinase C, and reactive oxygen species.

Osthole, a coumarin compound, has been reported to exhibit various biological activities; however the cellular mechanism of its immune modulating activity has not yet been fully addressed. In this study we isolated osthole from the seeds of Cnidium monnieri and demonstrated that osthole inhibited TNF-α, NO and COX-2 expression in LPS-stimulated macrophages, without reducing the expression of IL-6. Furthermore, the phosphorylation of p38, JNK1/2, PKC-α and PKC-ε induced by LPS was inhibited by osthole; however, the phosphorylation of ERK1/2 and PKC-δ was not reduced by osthole. Osthole also inhibited NF-κB activation and ROS release in LPS-stimulated macrophages. Our current results indicated that osthole is the major anti-inflammatory ingredient of Cnidium monnieri seed ethanol extract.

Composition and antimicrobial and anti-wood-decay fungal activities of the leaf essential oils of Machilus pseudolongifolia from Taiwan.

The hydrodistillated leaf essential oil of Machilus pseudolongifolia was analyzed to determine its composition and yield. Seventy compounds were identified, the main components being beta-eudesmol (26.8%), alpha-cadinol (20.8%), viridiflorene (8.9%), alpha-caryophyllene (5.3%), globulol (4.6%) and beta-caryophyllene (4.2%). Oxygenated sesquiterpenes (60.1%) and sesquiterpene hydrocarbons (31.4%) were the predominant groups of compounds. The leaf oil exhibited excellent antimicrobial and anti-wood-decay fungal activities.

Compositions and in vitro anticancer activities of the leaf and fruit oils of Litsea cubeba from Taiwan.

The leaf and fruit essential oils of Litsea cubeba, extracted by hydrodistillation, were assessed for anticancer activities. A total of 53 and 50 compounds were identified, respectively from the leaf and fruit oils, and their yields were 13.9 +/- 0.09% and 4.0 +/- 0.03%, v/w, of the oven-dried materials, respectively. The main compound in the leaf oil was 1,8-cineol, and in the fruit oil, citral. The fruit oil, but not that of the leaf, exhibited cytotoxic activity against human lung, liver and oral cancer cells.

Composition and antimicrobial activity of the leaf and twig oils of Litsea mushaensis and L. linii from Taiwan.

The hydrodistilled essential oils of the leaves and twigs of Litsea mushaensis and L. linii were analyzed. Sixty-nine and ninety compounds were identified in the leaf and twig oils, respectively, of L. mushaensis. The main components of the leaf oil were beta-eudesmol (24.2%), tau-cadinol (10.2%), alpha-humulene (10.1%), alpha-pinene (9.7%), and trans-beta-ocimene (6.5%), whereas the main components of the twig oil were trans-beta-ocimene (19.5%), alpha-pinene (12.8%) and cis-beta-ocimene (7.7%). With L. linii, 72 and 78 compounds were respectively identified in the leaf and twig oils. The main components of the leaf oil were beta-selinene (15.7%), alpha-selinene (15.5%), beta-caryophyllene (12.2%), alpha-humulene (7.2%), and delta-cadinene (5.6%), and of the twig oil trans-beta-ocimene (20.8%), beta-selinene (11.4%), alpha-cadinol (6.0%), delta-cadinene (5.8%), tau-cadinol (5.4%) and beta-eudesmol (5.2%). L. mushaensis leaf oil was shown to have excellent antimicrobial and anti-wood-decay fungal activity, superior to the other oils.