Architecture of chloroplast TOC-TIC translocon supercomplex.

Chloroplasts rely on the translocon complexes in the outer and inner envelope membranes (the TOC and TIC complexes, respectively) to import thousands of different nuclear-encoded proteins from the cytosol1-4. Although previous studies indicated that the TOC and TIC complexes may assemble into larger supercomplexes5-7, the overall architectures of the TOC-TIC supercomplexes and the mechanism of preprotein translocation are unclear. Here we report the cryo-electron microscopy structure of the TOC-TIC supercomplex from Chlamydomonas reinhardtii. The major subunits of the TOC complex (Toc75, Toc90 and Toc34) and TIC complex (Tic214, Tic20, Tic100 and Tic56), three chloroplast translocon-associated proteins (Ctap3, Ctap4 and Ctap5) and three newly identified small inner-membrane proteins (Simp1-3) have been located in the supercomplex. As the largest protein, Tic214 traverses the inner membrane, the intermembrane space and the outer membrane, connecting the TOC complex with the TIC proteins. An inositol hexaphosphate molecule is located at the Tic214-Toc90 interface and stabilizes their assembly. Four lipid molecules are located within or above an inner-membrane funnel formed by Tic214, Tic20, Simp1 and Ctap5. Multiple potential pathways found in the TOC-TIC supercomplex may support translocation of different substrate preproteins into chloroplasts.

Expert consensus on perioperative integrated skincare for noninvasive energy-based device aesthetic procedures in clinical practice in China.

BACKGROUND: Noninvasive energy-based device (NI-EBD) aesthetic procedures has recently gained widespread usage for treating various skin conditions, enhancing skin texture and performing rejuvenation-related procedures. However, practically all NI-EBD procedures result in variable degrees of damage to the skin barrier, inducing pathological and physiological processes such as oxidative stress and inflammation, and only a small percentage of individuals possess the innate ability to restore it. OBJECTIVE: To introduce the concept of integrated skincare and establish standardized operational procedures for perioperative integrated skincare, and furnish a theoretical basis for clinical diagnosis and treatment performed by professional medical aestheticians. METHODS: The author leveraged domestic and international guidelines, clinical practice expertise and evidence-based research, adapting them to suit the specific circumstances in China. RESULTS: The consensus were provided four parts, including concept and essence of integrated skincare, integrated skincare significance during the perioperative phase of NI-EBD procedures, active ingredients and functions of effective skincare products, standardized perioperative skincare procedure for NI-EBD procedures and precautions. For the standardized perioperative skincare procedure, four recommendations were listed according to different stages during NI-EBD procedures. CONCLUSION: These recommendations create the 'Expert Consensus on Perioperative Integrated Skincare for Noninvasive Energy-Based Device Aesthetic Procedures in Clinical Practice in China'.

Safety and efficacy of ultrasonography of tension after zone II flexor tendon repair: A randomized controlled trial.

BACKGROUND: Primary flexor tendon repairs of lacerations in zone II of the hand are fraught with problems. Traditionally, exercise (active and passive), orthoses, and physical agents are common interventions for the rehabilitation of patients experiencing these issues. One area of focus in this field is how to safely utilize tension to lengthen gliding distance following zone II injury. Finding effective solutions in this area is a key priority for improving patient outcomes and quality of life. PURPOSE: To identify the optimal immobilization position that meets safety standards for tension and is the most efficient, and consequently, to validate our clinical effectiveness. STUDY DESIGN: A cross-sectional study was adopted for the first part of the research (Research 1). A prospective, parallel, 2-group, randomized trial was conducted with concealed allocation and single blinding in the second part of the research (Research 2). METHODS: A total of 60 healthy adults were recruited to select the best-fit protective immobilization position in Research 1, which was confirmed by tendon tension (via Young's modulus) and excursion (via gliding distance). We then randomly assigned 45 patients after zone II flexor tendon repair into two groups in Research 2 to compare functional outcomes. The control group underwent the conventional modified Duran protocol with early passive motion, while the experimental group received the protocol (optimized by Research 1) with early active motion. Ultrasonography was used to measure the tension and excursion of the flexor tendons. The outcomes measured at 16 weeks post-repair included total active motion, strength, the Disabilities of the Arm, Shoulder and Hand, and Strickland scores. RESULTS: Three participants were unable to participate in Research 2 due to medical issues and poor attendance. The investigation found that the safe tendon threshold was 345.09 ± 87.74 kPa for partial active digital motion among the 60 participants. The optimal immobilization position requires the wrist to be neutral with a flexion angle of 30° at the metacarpophalangeal joint. The grip strengths (p = 0.012), ratio of grip strength (p = 0.015), the Disabilities of the Arm, Shoulder and Hand (p = 0.036), and total active motion (p = 0.023) differed significantly between the two groups. CONCLUSIONS: Protective immobilization of the wrist in a neutral flexion position and with the metacarpophalangeal joint flexed at 30° can secure the repaired flexor tendon safely and efficiently. The effects of an early active motion protocol may improve the grip strength and upper limb mobility of individuals after zone II flexor tendon repair. CLINICAL TRIAL REGISTRATION: ChiCTR2000030592.

[Current research status and application prospect of numerical simulation in traditional Chinese medicine drying].

With the rapid development of computer technology, numerical simulation has gradually become an important method to study drying process and improve drying equipment. Using computer to simulate the drying process of traditional Chinese medicine(TCM) is characterized by intuitiveness, scientificity, and low cost, which serves as an auxiliary means for technical innovation in TCM drying. This paper summarizes the theories of different drying methods and the research status of numerical simulation in drying, introduces the modeling methods and software of numerical simulation, and expounds the significance of numerical simulation modeling in shortening the research and development cycle, improving drying equipment, and optimizing drying parameters. However, the current numerical simulation method for drying process has problems, such as low accuracy, lack of quantitative indicators for the control of simulation results on the process, and insufficient in-depth research on the mechanism of drug quality changes. Furthermore, this paper put forward the application prospect of numerical simulation in TCM drying, providing reference for the further study of numerical simulation in this field.

[Current status, trends, and challenges of continuous manufacturing technology for oral traditional Chinese medicine solid preparations].

In recent years, continuous manufacturing technology has attracted considerable attention in the pharmaceutical industry. This technology is highly sought after for its significant advantages in cost reduction, increased efficiency, and improved productivity, making it a growing trend in the future of the pharmaceutical industry. Compared to traditional batch production methods, continuous manufacturing technology features real-time control and environmentally friendly intelligence, enabling pharmaceutical companies to produce drugs more efficiently. However, the adoption of continuous manufacturing technology has been slow in the field of traditional Chinese medicine(TCM) pharmaceuticals. On the one hand, there is insufficient research on continuous manufacturing equipment and technology that align with the characteristics of TCM preparations. On the other hand, the scarcity of talent with diverse expertise hampers its development. Therefore, in order to promote the modernization and upgrading of the TCM pharmaceutical industry, this article combined the current development status of the TCM industry to outline the development status and regulatory requirements of continuous manufacturing technology. At the same time, it analyzed the problems with existing TCM manufacturing models and explored the prospects and challenges of applying continuous manufacturing technology in the field of TCM pharmaceuticals. The analysis focused on continuous manufacturing control strategies, technical tools, and pharmaceutical equipment, aiming to provide targeted recommendations to drive the development of the TCM pharmaceutical industry.

Pore architecture of TRIC channels and insights into their gating mechanism.

Intracellular Ca2+ signalling processes are fundamental to muscle contraction, neurotransmitter release, cell growth and apoptosis. Release of Ca2+ from the intracellular stores is supported by a series of ion channels in sarcoplasmic or endoplasmic reticulum (SR/ER). Among them, two isoforms of the trimeric intracellular cation (TRIC) channel family, named TRIC-A and TRIC-B, modulate the release of Ca2+ through the ryanodine receptor or inositol triphosphate receptor, and maintain the homeostasis of ions within SR/ER lumen. Genetic ablations or mutations of TRIC channels are associated with hypertension, heart disease, respiratory defects and brittle bone disease. Despite the pivotal function of TRIC channels in Ca2+ signalling, their pore architectures and gating mechanisms remain unknown. Here we present the structures of TRIC-B1 and TRIC-B2 channels from Caenorhabditis elegans in complex with endogenous phosphatidylinositol-4,5-biphosphate (PtdIns(4,5)P2, also known as PIP2) lipid molecules. The TRIC-B1/B2 proteins and PIP2 assemble into a symmetrical homotrimeric complex. Each monomer contains an hourglass-shaped hydrophilic pore contained within a seven-transmembrane-helix domain. Structural and functional analyses unravel the central role of PIP2 in stabilizing the cytoplasmic gate of the ion permeation pathway and reveal a marked Ca2+-induced conformational change in a cytoplasmic loop above the gate. A mechanistic model has been proposed to account for the complex gating mechanism of TRIC channels.

Structure of spinach photosystem II-LHCII supercomplex at 3.2 Å resolution.

During photosynthesis, the plant photosystem II core complex receives excitation energy from the peripheral light-harvesting complex II (LHCII). The pathways along which excitation energy is transferred between them, and their assembly mechanisms, remain to be deciphered through high-resolution structural studies. Here we report the structure of a 1.1-megadalton spinach photosystem II-LHCII supercomplex solved at 3.2 Å resolution through single-particle cryo-electron microscopy. The structure reveals a homodimeric supramolecular system in which each monomer contains 25 protein subunits, 105 chlorophylls, 28 carotenoids and other cofactors. Three extrinsic subunits (PsbO, PsbP and PsbQ), which are essential for optimal oxygen-evolving activity of photosystem II, form a triangular crown that shields the Mn4CaO5-binding domains of CP43 and D1. One major trimeric and two minor monomeric LHCIIs associate with each core-complex monomer, and the antenna-core interactions are reinforced by three small intrinsic subunits (PsbW, PsbH and PsbZ). By analysing the closely connected interfacial chlorophylls, we have obtained detailed insights into the energy-transfer pathways between the antenna and core complexes.

Chemical peeling with 35% glycolic acid for the treatment of disseminated facial verruca plana: A randomized, split-face, evaluator-blinded trial.

Disseminated facial verruca plana is a chronic disorder that causes significant psychological distress. However, safe and effective treatment is lacking. This study aimed to explore the efficacy and safety of 35% glycolic acid (GA) for the treatment of disseminated facial verruca plana. A split-face clinical trial was conducted to explore the efficacy and safety of using chemical peeling with 35% GA for the treatment of disseminated facial verruca plana. One side of the face was applied with 35% GA once every fortnight for a total of three times. Adapalene gel was applied every night to the other side of the face as the control. The clearance rate of lesions was evaluated at different time points. Between June 2020 and December 2020, 30 patients with disseminated verruca plana who visited the Dermatology Hospital of Southern Medical University were enrolled. After three chemical peelings with 35% GA that was applied at 2-week intervals, 15 (50%) patients achieved >70% lesion reduction. The same effective rate in the adapalene gel-treated side of the face was documented in eight patients. Subgroup analysis showed a higher clearance rate in patients with a shorter disease duration. Moreover, concurrent improvements in facial roughness were observed in the 35% GA-treated group. Adverse effects including mild erythema and desquamation were observed during chemical peeling with 35% GA. In conclusion, chemical peeling with 35% GA could be a safe and effective option for treating disseminated facial verruca plana, especially for those who desire skin improvement.

Neutrophils and their extracellular traps impair ablative fractional carbon dioxide laser-induced dermal remolding in mice.

OBJECTIVES: Ablative fractional CO2 laser (AFL) therapy is an effective intervention to induce dermal remodeling. AFL treatment of the skin triggers the recruitment of immune cells, with neutrophils dominating the early phase. However, the role of recruited neutrophils in AFL-induced microinjuries and their subsequent dermal remodeling capacity remains elusive. MATERIALS AND METHODS: A mouse model of AFL-induced dermal remodeling was established. RNA sequencing was used to identify the prominent features of AFL-treated tissues. Histological analysis, including H&E and Masson staining, ultrastructure observation by transmission microscopy, immunofluorescence, and quantitative real-time polymerase chain reaction were used for dermal remodeling analysis. Moreover, AFL-treated mice were intraperitoneally injected with anti-mouse Ly6G antibodies to deplete neutrophils. Neutrophil extracellular traps (NETs) were explored using immunofluorescence, transmission microscopy, and in vitro coculture experiments. RESULTS: Dermal remodeling, characterized by an increased number of CD31-positve vessels and elevated messenger RNA (mRNA) expression of genes encoding transforming growth factor-ß (TGF-ß), collagen I, and collagen III, was observed at 15 days after AFL treatment. In the AFL-induced inflammation phase, RNA sequencing identified neutrophil chemotaxis, and degranulation genes were significantly enriched. Histology and immunofluorescence staining of human and mouse tissues harvested at Day 1 after AFL treatment revealed significant neutrophil infiltration surrounding thermal-induced microinjuries. Neutrophil depletion decreased the expression of stress-related genes such as S100A8 and S100A9 in the early phase following AFL treatment. Importantly, neutrophil depletion enhanced dermal remodeling at Day 15, as reflected by enrichment of the extracellular matrix and collagen biosynthesis genes based on RNA sequencing. Moreover, increased collagen I, collagen III, and TGF-ß mRNA expression, increased cell proliferation, and vascularity were observed. Interestingly, NETs, which could be induced by AFL-treated fibroblasts in vitro, were identified in both human and mouse tissues on Day 1 after AFL treatment. CONCLUSIONS: AFL-treated human and mouse skin recruited a large number of neutrophils. The neutrophil surge impaired dermal remodeling in mice. The microenvironment and fibroblast functional modulation mediated by neutrophil degranulation and NET formation were determined to be the underlying mechanisms. Our results indicate that modification of infiltrated neutrophil activity might be a potential therapeutic target for AFL-induced dermal remodeling.

Efficacy and safety of 755 nm Q-switched Alexandrite Laser for Hori's nevus: a retrospective analysis of 482 Chinese women.

To evaluate the efficacy and safety of 755 nm Q-Switched alexandrite laser for Hori's nevus in a large cohort of Chinese women. We retrospectively analyzed the efficacy and safety of 755 nm Q-Switched alexandrite laser for Hori's nevus. Reduction in pigment was evaluated using a 4-score method. A total of 482 patients, aged 16 to 52 years, were included in this analysis. Patients were treated with 755 nm Q-Switched alexandrite laser at fluence levels of 5-8 J/cm2 for 2-4 treatment sessions. Following the treatments, 53% of patients showed over 75% reductions in pigment while 50-75% reductions in pigment were observed in 28% of patients. The rest displayed less than 50% improvements. Efficacy was positively correlated with the number of treatment sessions (p < 0.0001). Adverse reactions were temporary, mild erythema, and edema. A small portion of patients (15%) had hyperpigmentation, which disappeared within 2-6 months. 755 nm Q-Switched alexandrite laser is safe and has moderate benefits for Hori's nevus. Because its efficacy is positively correlated with the number of treatment sessions, increase in treatment sessions possibly could achieve a better outcome.

Ultrasonographic assessment in vivo of the excursion and tension of flexor digitorum profundus tendon on different rehabilitation protocols after tendon repair.

STUDY DESIGN: Interpretive description study. PURPOSE: In management of patients with flexion tendon injuries, passive, control active and active motion protocols were proposed after repair to minimize tendon adhesion. The purpose of this study was to compare the excursion distance and the tension of Flexor Digitorum Profundus (FDP) during simulated active and passive motion using ultrasonography techniques using normal subjects. METHODS: Ultrasonographic assessment of FDP tendon of the middle finger was performed at the wrist level on 20 healthy college students using 3 types of treatment protocols: modified Kleinert protocol, modified Duran protocol, and active finger flexion protocol. The excursion distance was measured following the musculotendinous junction of FDP using the B mode ultrasound system. The elasticity of FDP tendon was measured using the shear wave elastography technique. The excursion distance and the elasticity value were compared among 3 protocols using one-way ANOVA analysis. RESULTS: Twelve male and 8 female students with mean age of 22.6 ± 1.8 years were invited to join the study. The excursion distance of FDP was 21.82 ± 3.77 mm using the active finger flexion protocol, 8.59 ± 2.59 mm using the modified Duran protocol, and 12.26 ± 2.71 mm using the modified Kleinert protocol. The elasticity was significantly higher in extension position when compared to passive flexion positions, but found lower than active flexion position. DISCUSSION: The active finger protocol was found to require strongest tension of the tendon and with longest excursion. There was similar tension generated using both passive motion protocols. The modified Duran protocol appeared to create less excursion upon movements than the modified Kleinert approach using the objective ultrasonic evaluation. It is suggested that if the surgical repair was strong and without any complications, the active flexion protocol might work best to regain tension excursion. However, if there are complex problems involved, then the Kleinert approach or Duran approach would be chosen.

[Quality control mode based on engineering quality view of Chinese medicine pharmacy].

Due to the characteristics of confusing varieties of Chinese medicinal materials, different sources, complex chemical composition, non-standard preparation process, and non-standard pharmaceutical equipment, the quality of Chinese medicinal preparations is difficult to be controlled and evaluated effectively under the current quality control mode and method of Chinese medicinal preparation. The present study proposed an engineering quality view of Chinese medicine pharmacy and a strategy to control the quality of Chinese medicinal preparations based on the current situation. The "overall, dialectical, and dynamic" multi-factor engineering quality view, covering original medicinal materials, preparation technologies, pharmaceutical equipment, and Chinese medicinal preparations, ensures the traceable process, measurable procedures, and feedback quality. The quality control mode of Chinese medicinal preparation with controllable sources, standardized preparation technologies, green pharmaceutical equipment, and intelligent manufacturing is built up.

Plant and Algal PSII-LHCII Supercomplexes: Structure, Evolution and Energy Transfer.

Photosynthesis is the process conducted by plants and algae to capture photons and store their energy in chemical forms. The light-harvesting, excitation transfer, charge separation and electron transfer in photosystem II (PSII) are the critical initial reactions of photosynthesis and thereby largely determine its overall efficiency. In this review, we outline the rapidly accumulating knowledge about the architectures and assemblies of plant and green algal PSII-light harvesting complex II (LHCII) supercomplexes, with a particular focus on new insights provided by the recent high-resolution cryo-electron microscopy map of the supercomplexes from a green alga Chlamydomonas reinhardtii. We make pair-wise comparative analyses between the supercomplexes from plants and green algae to gain insights about the evolution of the PSII-LHCII supercomplexes involving the peripheral small PSII subunits that might have been acquired during the evolution and about the energy transfer pathways that define their light-harvesting and photoprotective properties.

Osteopontin-induced lncRNA HOTAIR expression is involved in osteoarthritis by regulating cell proliferation.

BACKGROUND: Osteopontin plays critical roles in osteoarthritis (OA) by regulating the functions of osteoclasts. It is known that osteopontin can induce the expression of lncRNA HOX transcript antisense RNA (HOTAIR), indicating the involvement of HOTAIR in OA. This study was carried out to investigate the role of HOTAIR in OA. METHODS: Synovial fluid was extracted from both OA patients (n = 58) and healthy controls (n = 58). Expression of osteopontin and HOTAIR in synovial fluid was determined by RT-qPCR. Osteopontin was used to treat chondrocytes at dosages of 0, 1, 5 and 10 µg/ml, followed by measurement of HOTAIR expression by RT-qPCR. The role of osteopontin and HOTAIR overexpression, as well as HOTAIR knockdown in regulating the proliferation of chondrocytes was analyzed by cck-8 assay. RESULTS: HOTAIR was upregulated in OA. A positive correlation between HOTAIR and osteopontin was observed. In the primary chondrocytes, osteopontin treatment increased HOTAIR expression, while HOTAIR overexpression and knockdown failed to significantly affect osteopontin expression. In addition, osteopontin and HOTAIR overexpression increased chondrocyte proliferation, while HOTAIRE knockdown decreased chondrocyte proliferation. In addition, HOTAIR knockdown reduced the effects of osteopontin treatment on cell proliferation. CONCLUSIONS: Osteopontin-induced HOTAIR expression is involved in osteoarthritis by regulating cell proliferation.

The prevalence of HIV among MSM in China: a large-scale systematic analysis.

BACKGROUND: The prevalence of HIV among men who have sex with men (MSM) has become a significant public health challenge. The aim was to comprehensively estimate the national prevalence of HIV among MSM and its time trends through a large-scale systematic analysis. METHODS: Systematic search of Cochrane Library, PubMed, EMBASE, CNKI, VIP, and Wanfang Data databases without language restriction for studies on the prevalence of HIV among MSM published before Dec.31, 2018. Studies were eligible for inclusion if they were published in the peer-reviewed literature and used validated assessment methods to assess the prevalence of HIV among MSM. Estimates were pooled using random-effects analysis. RESULTS: Data were extracted from 355 cross-sectional studies (571,328 individuals) covered 59 cities from 30 provinces and municipalities of China. The overall national prevalence of HIV among MSM from 2001 to 2018 was estimated to be 5.7% (95% CI: 5.4-6.1%), with high between-study heterogeneity (I2 = 98.0%, P <  0.001). Our study showed an increased tendency in the HIV prevalence as time progressed by meta-regression analysis (I2 = 95.9%, P <  0.0001). HIV prevalence was the highest in those aged 50 years and older with HIV prevalence of 19.3% (95%CI: 13.1-27.4%, N = 13). HIV was more prevalent in the illiterate population (16.8%), than in those who had received an education. Although the internet was a major venue for Chinese MSM seeking male sex partners (35.6, 95%CI: 32.3-39.9%, N = 101), seeking MSM in bathhouses/saunas had the highest associated prevalence of HIV (13.4, 95%CI: 10.3-17.1%, N = 22). The HIV prevalence among MSM varied by location: compared with other regions in China, HIV was highly prevalent among MSM in the southwest (10.7, 95%CI: 9.3-12.2%, N = 91). Compared to participants who sometimes or always used condoms, participants who had never used a condom in the past 6 months had a higher risk of HIV infection, with odds ratios of 0.1 (95%CI: 0.08-0.14). CONCLUSIONS: Our analysis provided reliable estimates of China's HIV burden among MSM, which appears to present an increasing national public health challenge. Effective government responses are needed to address this challenge and include the implementation of HIV prevention.

[Application prospect of new technology and new equipment in production of Chinese patent medicine].

At present,the production equipment and process of Chinese patent medicines still have many problems including high energy consumption,low efficiency,high pollution,and low intelligence,which seriously hinder the transformation,upgrading and modernized development of traditional Chinese medicine industry. With the emergence of various new pharmaceutical technologies and the application of technologies of other fields in traditional Chinese medicine industry,the development of Chinese patent medicine has ushered in new opportunities. The processes such as pulverization,mixing,extraction,separation,concentration,drying and sterilization are unique for the production of Chinese patent medicine. These main features can be distinguished from the manufacturing process of chemical drugs,determining the characteristics of the production process and equipment of Chinese patent medicine. In this paper,each operation unit was mentioned to summarize and analyze the new equipment and new technologies with advantages and characteristics in recent years from the perspectives of definition,principle,classification and application. Among them,the automatic spray device of the mixer,the extraction and separation equipment of volatile oil,and the crane basket-type circulation extraction technology,composite multi-layer spiral vibration countercurrent drying,and vibration sterilization equipment all have rapid development in recent years,with great prospects in the production of Chinese patent medicines. In this paper,we also analyzed some problems existing in the production equipment and technology of Chinese patent medicine and the key factors restricting the development of Chinese patent medicine,discussed the transformation of Chinese patent medicine production from traditional to modern and from semi-automatic to intelligent,and put forward three suggestions to help Chinese patent medicine achieve the goal of improving quality,efficiency and green manufacturing in production.

[Discussion on research thought of dry granulation of traditional Chinese medicine: research progress at home and abroad based on dry granulation technology].

Dry granulation technology is a great innovation in granulation technology,which saves many intermediate links and reduces many intermediate costs. It is closely related to the characteristics of materials,dry granulation equipment and process. Dry granulation technology is a systematic engineering science covering many technical fields. The process of dry granulation involves complex mathematical model mechanisms of temperature field,pressure field and velocity field,closely related to the characteristics of materials and drying equipment. However,due to the late start of research on dry granulation technology of traditional Chinese medicine,basic research is still weak. The research on dry granulation technology has achieved great results in the fields of food,chemical industry,agriculture and forestry,showing great reference significance. The advantage of dry granulation of traditional Chinese medicine is that it can be directly granulated by adding an appropriate amount of auxiliary materials in the extract powder of traditional Chinese medicine,without the need of wetting,mixing,drying and other processes. The process is simple and can effectively guarantee the quality of traditional Chinese medicine. The granules obtained by the dry granulation technique are important intermediates for preparing the solid preparations of traditional Chinese medicines,which would directly affect the subsequent molding process and the quality of the preparation products. Therefore,based on the characteristics of dry granulation method in traditional Chinese medicine and by referring to the advanced research results of dry granulation technology in other fields,we would discuss the research ideas of dry granulation in traditional Chinese medicine in terms of the mechanism of dry granulation equipment,technology,on-line detection technology and mathematical model of dry granulation process,hoping to provide reference for the research of dry granulation method in traditional Chinese medicine.

Structure, assembly and energy transfer of plant photosystem II supercomplex.

Around photosystem II (PSII), the peripheral antenna system absorbs sunlight energy and transfers it to the core complex where the water-splitting and oxygen-evolving reaction takes place. The peripheral antennae in plants are composed of various light-harvesting complexes II (LHCII). Recently, the three-dimensional structure of the C2S2M2-type PSII-LHCII supercomplex from Pisum sativum (PsPSII) has been solved at 2.7-Šresolution using the single-particle cryo-electron microscopy method. The large homodimeric supercomplex has a total molecular weight of >1400 kDa. Each monomer has a core complex surrounded by strongly and moderately bound LHCII trimers, as well as CP29, CP26, and CP24 monomers. Here, we review and present a detailed analysis of the structural features of this supramolecular machinery. Specifically, we discuss the structural differences around the oxygen-evolving center of PSII from different species. Furthermore, we summarize the existing knowledge of the structures and locations of peripheral antenna complexes, and dissect the excitation energy transfer pathways from the peripheral antennae to the core complex. This detailed high-resolution structural information provides a solid basis for understanding the functional behavior of plant PSII-LHCII supercomplex.

Shifting metabolic priorities among key protistan taxa within and below the euphotic zone.

A metatranscriptome study targeting the protistan community was conducted off the coast of Southern California, at the San Pedro Ocean Time-series station at the surface, 150 m (oxycline), and 890 m to link putative metabolic patterns to distinct protistan lineages. Comparison of relative transcript abundances revealed depth-related shifts in the nutritional modes of key taxonomic groups. Eukaryotic gene expression in the sunlit surface environment was dominated by phototrophs, such as diatoms and chlorophytes, and high abundances of transcripts associated with synthesis pathways (e.g., photosynthesis, carbon fixation, fatty acid synthesis). Sub-euphotic depths (150 and 890 m) exhibited strong contributions from dinoflagellates and ciliates, and were characterized by transcripts relating to digestion or intracellular nutrient recycling (e.g., breakdown of fatty acids and V-type ATPases). These transcriptional patterns underlie the distinct nutritional modes of ecologically important protistan lineages that drive marine food webs, and provide a framework to investigate trophic dynamics across diverse protistan communities.

Structural Mechanism Underlying the Specific Recognition between the Arabidopsis State-Transition Phosphatase TAP38/PPH1 and Phosphorylated Light-Harvesting Complex Protein Lhcb1.

During state transitions, plants regulate energy distribution between photosystems I and II through reversible phosphorylation and lateral migration of the major light-harvesting complex LHCII. Dephosphorylation of LHCII and the transition from state 2 to state 1 requires a thylakoid membrane-associated phosphatase named TAP38 or PPH1. TAP38/PPH1 specifically targets LHCII but not the core subunits of photosystem II, whereas the underlying molecular mechanism of their mutual recognition is currently unclear. Here, we present the structures of Arabidopsis thaliana TAP38/PPH1 in the substrate-free and substrate-bound states. The protein contains a type 2C serine/threonine protein phosphatase (PP2C) core domain, a Mn(2+) (or Mg(2+)) binuclear center and two additional motifs contributing to substrate recognition. A 15-mer phosphorylated N-terminal peptide of Lhcb1 binds to TAP38/PPH1 on two surface clefts enclosed by the additional motifs. The first segment of the phosphopeptide is clamped by a pair of tooth-like arginine residues at Cleft 1 site. The binding adopts the lock-and-key mechanism with slight rearrangement of the substrate binding residues on TAP38/PPH1. Meanwhile, a more evident substrate-induced fitting occurs on Cleft 2 harboring the extended part of the phosphopeptide. The results unravel the bases for the specific recognition between TAP38/PPH1 and phosphorylated Lhcb1, a crucial step in state transitions.