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Background: Astaxanthin is a kind of tetraterpene and has strong antioxygenic property. The biosynthesis of astaxanthin in engineered microbial chassis has greater potential than its chemical synthesis and extraction from natural producers in an environmental-friendly way. However, the cost-offsetting production of astaxanthin in engineered microbes is still constrained by the poor efficiency of astaxanthin synthesis pathway as a heterologous pathway.Results: To address the bottleneck of limited production of astaxanthin in microbes, we developed in vitro and in vivo recombination methods respectively in engineered yeast chassis to optimize the combination of heterologousβ-carotene ketolase (crtW) and hydroxylase (crtZ) modules that were selected from different species. As a result, the in vitro and in vivo recombination methods enhanced the astaxanthin yield respectively to 2.11~8.51 folds and 3.0~9.71 folds compared to the initial astaxanthin pathway, according to the different combination of particular genes. The highest astaxanthin producing strain yQDD022 was constructed by in vivo method and produced 6.05 mg/g DCW of astaxanthin. Moreover, it was proved that the in vivo recombination method showed higher DNA-assembling efficiency than the in vitro method and contributed to higher stability to the engineered yeast strains.Conclusions: The in vitro and in vivo recombination methods of heterologous modules provide simple and efficient ways to improve the astaxanthin yield in yeast. Both the two methods enable high-throughput screening of heterologous pathways through recombination of certain crtW and crtZ derived from different species. This study not only exploited the underlying optimal combination of crtZ and crtW for astaxanthin synthesis, but also provided a general approach to evolve a heterologous pathway for the enhanced accumulation of desired biochemical products.

Although it is difficult in fully clarifying its mechanisms and effects,Deqistill can be considered as an instant “sign” of acupuncture response of the patient and acupuncturist, which has a significant value in clinic and research. This paper aims to take a history trace to the development ofDeqitheory, understand the connotation ofDeqibased on Chinese medicine theory, and establish an evaluation methodology accordingly. We believe thatDeqiis not only the needling sensation, but also the perception of changes ofqi'flowing of the patient elicited by needling on acupoints. The signs ofDeqiinclude the patient’s subjective perception (needling sensation), the objective physiological changes (common referred to the skin redness around the acupoints and the response of brain), and the acupuncturists' perception. AlthoughDeqiis essential for attaining the effect, it may not be the necessary sign of the ideal efficacy. It is found that the characteristics ofDeqisensations,Deqi’s intensity, time duration, and the propagation will all affect the efficacy. Thus, acupuncturists should pay attention to elicit and controlDeqistate, which is also the key point in modern research on the therapeutic implications ofDeqi.

Arbuscular mycorrhiza fungi (AMF) can colonize the roots of Amorpha fruticosa, a perennial leguminous woody shrub and form arbuscular mycorrhiza (AM). AMF have significant promoting effects on A. fruticosa growth as the intensity of fungal colonization increases. Taking AMF-A. fruticosa symbionts as the experimental material, gel-free isobaric tags for relative and absolute quantification (iTRAQ) coupled with two-dimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to investigate the expression of A. fruticosa mycorrhizal proteins at the maturation stage. A total of 3,473 proteins were identified, of which 77 showed dramatic changes in their root expression levels; 33 increased and 44 decreased. We also found nine AMF proteins that were expressed with AMF treatment. The 77 proteins were classified according to function. Plant proteins were assigned into 11 categories: metabolism-related (32%), protein folding and degradation-related (22%), energy-related (10%), protein synthesis-related (8%), stress and defense-related (24%), transcription-related (6%), membrane and transport-related (4%), cellular structure-related (2.5%), signaling transduction-related (11%) and unknown proteins (5%). The results of the study provide a foundation for further investigation of the metabolic characteristics and molecular mechanisms of AM.

Background. Deqi sensation is a complex but an important component for acupuncture effect. In this study, we tried to observe the relationship between Deqi and skin temperature changes and whether there was some relativity between Deqi and needle stimulations on cold congealing and dysmenorrhea rat model. Thirty-two female Sprague Dawley (SD) rats were randomly divided into four groups (Saline Control Group, Model Group, Group A with strong stimulation, and Group B with small stimulation). Group A and Group B were performed with different stimulations. We found that, compared with saline control group, model group, and Group B, Group A showed that the skin temperature changes on right acupoint SP6 and SP10 increased significantly at 5 min–10 min interval. The skin temperature changes on left SP6 decreased at instant–5 min interval. The skin temperature changes on right SP10 decreased significantly at instant–5 min interval and 10 min–20 min interval. Thermogenic action along Spleen Meridian of Foot Greater Yin was manifested as simultaneous skin temperature increase on right SP6 and SP10 at 5 min–10 min interval after needling SP6, which was helpful to illustrate the relationship between the characteristic of Deqi and needle stimulations.

In this study, we try to evaluate the effects of acupuncture stimulation with different amounts at Sanyinjiao (SP6) on uterine contraction and uterus microcirculation in rats with dysmenorrhea of cold coagulation syndrome and to explore whether there is direct relativity between “De qi” and needle stimulus intensity. Diestrus female rats were randomly divided into 4 groups, including saline control group, model control group, “A” stimulus group (with strong stimulus), and “B” stimulus group (with weak stimulus). We found that dysmenorrhea rats of the cold coagulation syndrome present a high intensity in uterine tension and high contraction of microvascular diameter. Acupuncture applied with two different stimuli could relieve the symptoms, but, compared with “B” stimulus, “A” stimulus leads to better outcomes on reducing uterine contraction and increasing diameter of uterine microvascular; moreover, hand manipulation during needling mediates the curative effect on the microvascular diameter. Our finding indicates that using thick needles and deep insertion with hand manipulation are more effective and achieve desired level of “De qi” in dysmenorrhea rats.

Deqisensation is believed to be important in clinical efficacy according to TCM theory. The measuring method ofDeqisensation has significant implications for the result of research trials. This study makes an investigation on acupuncture-experienced patients and expert acupuncturists in China and aims to find out the patient’s needling sensations and acupuncturist’s sensations which can be acceptable as descriptors ofDeqisensation, so as to provide foundation for more systematic and sensitive quantitative evaluation method ofDeqisensation. Results of this survey indicated that theDeqisensation noted by both patient and acupuncturist is equally important to the treatment efficacy. It is found that there are some differences between the patients’ real-life experience and the acupuncturists’ expectations on patients’Deqisensation. The “dull pain,” “aching,” “sore,” “numb,” “distended,” “heavy,” “electric,” “throbbing,” “warmness,” “coolness,” “spreading,” and “radiating” can be considered as the main manifestations ofDeqisensations. The acupuncturists believed thatDeqisensations were mainly “pulling,” “tight,” and “throbbing.” We suggest developing a questionnaire measuring theDeqisensations which includes both the sensations of the patient and acupuncturist, and this would be very important and necessary for a better understanding of the relationship betweenDeqisensation and acupuncture effects in future studies.

Background The family Camelidae that evolved in North America during the Eocene survived with two distinct tribes, Camelini and Lamini. To investigate the evolutionary relationship between them and to further understand the evolutionary history of this family, we determined the complete mitochondrial genome sequence of the wild two-humped camel (Camelus bactrianus ferus), the only wild survivor of the Old World camel. Results The mitochondrial genome sequence (16,680 bp) from C. bactrianus ferus contains 13 protein-coding, two rRNA, and 22 tRNA genes as well as a typical control region; this basic structure is shared by all metazoan mitochondrial genomes. Its protein-coding region exhibits codon usage common to all mammals and possesses the three cryptic stop codons shared by all vertebrates. C. bactrianus ferus together with the rest of mammalian species do not share a triplet nucleotide insertion (GCC) that encodes a proline residue found only in the nd1 gene of the New World camelid Lama pacos. This lineage-specific insertion in the L. pacos mtDNA occurred after the split between the Old and New World camelids suggests that it may have functional implication since a proline insertion in a protein backbone usually alters protein conformation significantly, and nd1 gene has not been seen as polymorphic as the rest of ND family genes among camelids. Our phylogenetic study based on complete mitochondrial genomes excluding the control region suggested that the divergence of the two tribes may occur in the early Miocene; it is much earlier than what was deduced from the fossil record (11 million years). An evolutionary history reconstructed for the family Camelidae based on cytb sequences suggested that the split of bactrian camel and dromedary may have occurred in North America before the tribe Camelini migrated from North America to Asia. Conclusion Molecular clock analysis of complete mitochondrial genomes from C. bactrianus ferus and L. pacos suggested that the two tribes diverged from their common ancestor about 25 million years ago, much earlier than what was predicted based on fossil records.