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The photosynthetic mechanism of crop yields in fluctuating light environments in the field remains controversial. To further elucidate this mechanism, we conducted field and simulation experiments using maize (Zea mays) plants. Increased planting density enhanced the light fluctuation frequency and reduced the duration of daily high light, as well as the light-saturated photosynthetic rate, biomass, and yield per plant. Further analysis confirmed a highly significant positive correlation between biomass and yield per plant and the duration of photosynthesis related to daily high light. The simulation experiment indicated that the light-saturated photosynthetic rate of maize leaves decreased gradually and considerably when shortening the daily duration of high light. Under an identical duration of high light exposure, increasing the fluctuation frequency decreased the light-saturated photosynthetic rate slightly. Proteomic data also demonstrated that photosynthesis was mainly affected by the duration of high light and not by the light fluctuation frequency. Consequently, the current study proposes that an appropriate duration of daily high light under fluctuating light environments is the key factor for greatly improving photosynthesis. This is a promising mechanism by which the photosynthetic productivity and yield of maize can be enhanced under complex light environments in the field., Competing Interests: Conflict of interest statement. The authors declare no conflicts ofinterest., (© American Society of Plant Biologists 2022. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Chlorophyll a fluorescence induction kinetics (CFI) is an important tool that reflects the photosynthetic function of leaves, but it remains unclear whether it is affected by leaf structure. Therefore, in this study, the leaf structure and CFI curves of sunflower and sorghum seedlings were analyzed. Results revealed that there was a significant difference between the structures of palisade and spongy tissues in sunflower leaves. Their CFI curves, measured on both the adaxial and abaxial sides, also differed significantly. However, the differences in the leaf structures and CFI curves between both sides of sorghum leaves were not significant. Further analysis revealed that the differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves almost disappeared due to reduced incident light scattering and refraction in the leaf tissues; more importantly, changes in the CFI curves of the abaxial side were greater than the adaxial side. Compared to leaves grown under full sunlight, weak light led to decreased differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves; of these, changes in the CFI curves and palisade tissue structure on the adaxial side were more obvious than on the abaxial side. Therefore, it appears that large differences in sunflower leaf structures may affect the shape of CFI curves. These findings lay a foundation for enhancing our understanding of CFI from a new perspective.

A leaf structure with high porosity is beneficial for lateral CO 2 diffusion inside the leaves. However, the leaf structure of maize is compact, and it has long been considered that lateral CO 2 diffusion is restricted. Moreover, lateral CO 2 diffusion is closely related to CO 2 pressure differences (ΔCO 2 ). Therefore, we speculated that enlarging the ΔCO 2 between the adjacent regions inside maize leaves may result in lateral diffusion when the diffusion resistance is kept constant. Thus, the leaf structure and gas exchange of maize (C 4 ), cotton (C 3 ), and other species were explored. The results showed that maize and sorghum leaves had a lower mesophyll porosity than cotton and cucumber leaves. Similar to cotton, the local photosynthetic induction resulted in an increase in the ΔCO 2 between the local illuminated and the adjacent unilluminated regions, which significantly reduced the respiration rate of the adjacent unilluminated region. Further analysis showed that when the adjacent region in the maize leaves was maintained under a steady high light, the photosynthesis induction in the local regions not only gradually reduced the ΔCO 2 between them but also progressively increased the steady photosynthetic rate in the adjacent region. Under field conditions, the ΔCO 2 , respiration, and photosynthetic rate of the adjacent region were also markedly changed by fluctuating light in local regions in the maize leaves. Consequently, we proposed that enlarging the ΔCO 2 between the adjacent regions inside the maize leaves results in the lateral CO 2 diffusion and supports photosynthesis in adjacent regions to a certain extent under fluctuating light.

Low light conditions not only induce leaf senescence, but also photosynthetic acclimation. This study aimed to determine whether plants exhibit photosynthetic acclimation during low-light-induced leaf senescence. The influences of shading on leaf senescence and photosynthetic acclimation were explored in post-anthesis maize plants. The results showed that whole shading (WS) of maize plants accelerated leaf senescence, whereas partial shading (PS) slowed leaf senescence. WS led to larger decreases in the photosynthetic rate (P n ) and stomatal conductance (G s ) compared to those of the PS treatment. Interestingly, chlorophyll a fluorescence (ChlF) demonstrated that the absorption flux (ABS/CS o ) and trapped energy flux (TR o /CS o ) per cross section in leaves remained relatively stable under WS, whereas significant decreases in the active PSII reaction centers (RC/CS o ) resulted in considerable increases in absorption (ABS/RC) and trapped energy flux (TR o /RC) per reaction center. ABS/CS o , TR o /CS o , ABS/RC, and TR o /RC increased markedly under PS, whereas there were slight decreases in RC/CS o and electron transport activity. These results suggest that the PS treatment resulted in obvious improvements in the absorption and capture of light energy in shaded leaves. Further analysis demonstrated that both the WS and PS treatments resulted in a greater decrease in the activity of Rubisco compared to that of phosphoenolpyruvate carboxylase (PEPC). Moreover, PEPC activity in PS was maintained at a high level. Consequently, the current study proposed that the improvement of the absorption and capture of light energy and the maintenance of PEPC activity of mesophyll cells were due to photosynthetic acclimation of low-light-induced leaf senescence in maize plants. In addition, the rate of senescence of vascular bundle cells in maize leaves exceeded that of mesophyll cells under low light, showing obvious tissue specificity., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Plants in their natural environment are often exposed to fluctuating light because of self-shading and cloud movements. As changing frequency is a key characteristic of fluctuating light, we speculated that rapid light fluctuation may induce rapid photosynthetic responses, which may protect leaves against photoinhibition. To test this hypothesis, maize seedlings were grown under fluctuating light with various frequencies (1, 10, and 100 cycles of fluctuations/10 h), and changes in growth, chlorophyll content, gas exchange, chlorophyll a fluorescence, and P700 were analyzed carefully. Our data show that though the growth and light-saturated photosynthetic rate were depressed by rapidly fluctuating light, photosynthesis induction was clearly speeded up. Furthermore, more rapid fluctuation of light strikingly reduced the chlorophyll content, while thermal dissipation was triggered and enhanced. The chlorophyll a fluorescence induction kinetics and P700 absorption results showed that the activities of both photosystem II and photosystem I decreased as the frequency of the fluctuating light increased. In all treatments, the light intensities of the fluctuating light were kept constant. Therefore, rapid light fluctuation frequency itself induced the acceleration of photosynthetic induction and the enhancement of photoprotection in maize seedlings, which play important roles in protecting photosynthetic apparatus against fluctuating high light to a certain extent., (© 2020. Springer Nature B.V.)

To copy with highly heterogeneous light environment, plants can regulate photosynthesis locally and systemically, thus, maximizing the photosynthesis of individual plants. Therefore, we speculated that local weak light may induce the improvement of photosynthesis in adjacent illuminated leaves in plants. In order to test this hypothesis, maize seedlings were partially shaded, and gas exchange, chlorophyll a fluorescence and biochemical analysis were carefully assessed. It was shown that local shading exacerbated the declines in the photosynthetic rates, chlorophyll contents, electron transport and carbon assimilation-related enzyme activities in shaded leaves as plants growth progressed. While, the decreases of these parameters in adjacent illuminated leaves of shaded plants were considerably alleviated compared to the corresponding leaves of control plants. Obviously, the photosynthesis in adjacent illuminated leaves in shaded plants was improved by local shading, and the improvement in adjacent lower leaves was larger than that in adjacent upper ones. As growth progressed, local shading induced higher abscisic acid contents in shaded leaves, but it alleviated the increase in the abscisic acid contents in adjacent leaves in shaded plants. Moreover, the difference in sugar content between shaded leaves and adjacent illuminated ones was gradually increased. Consequently, local weak light suppressed the photosynthesis in shaded leaves, while it markedly improved the photosynthesis of adjacent illuminated ones. Sugar gradient between shaded leaves and adjacent illuminated ones might play a key role in photosynthetic regulation of adjacent illuminated leaves., (© 2020 Scandinavian Plant Physiology Society.)

A 59-year-old man with refractory Cronkhite-Canada syndrome (CCS) had poor clinical response to high-dose intravenous steroids, azathioprine, total parenteral nutrition and best supportive care. He remained highly symptomatic with abdominal pain, diarrhoea, recurrent sepsis and profound weight loss. Infliximab induction was given as rescue therapy, with marked clinical improvement observed within 3 weeks. This allowed steroid taper. Within 12 months of infliximab therapy, he achieved complete clinical remission and returned to his baseline weight and a full oral diet. Sequential endoscopies observed significant regression of previous marked gastrointestinal polyposis, including histological remission on colonic biopsies at 3.5 and 5 years of treatment. He currently remains in remission following 6 years of combination therapy with 5 mg/kg 8 weekly infliximab and azathioprine, and there is ongoing discussion with regard to the benefits and risks of therapy de-escalation. This case demonstrates the effectiveness of infliximab in inducing and maintaining remission in refractory CCS., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Zirconia material has a color closer to human natural teeth, and has excellent mechanical properties and good biocompatibility, therefore it is expected to become an ideal material for dental implants. In order to improve the osteogenic properties of zirconia implants, a variety of surface treatment techniques emerge in two categories: non-coating method and coating method. Different surface treatment technologies have their advantages and disadvantages. In this paper, the recent progress of zirconia surface treatment technology is reviewed.

There are considerable variations in the percentage loss of hydraulic conductivity ( PLC ) at mid-day minimum water potential among and within species, but the underpinning mechanism(s) are poorly understood. This study tested the hypothesis that plants can regulate leaf specific hydraulic conductance ( K l ) via precise control over PLC under variable Δ Ψ (water potential differential between soil and leaf) conditions to maintain the -m/b constant ( -m : the sensitivity of stomatal conductance to VPD ; b : reference stomatal conductance at 1.0 kPa VPD ), where VPD is vapor pressure deficit. We used Populus euphratica , a phreatophyte species distributed in the desert of Northwestern China, to test the hypothesis. Field measurements of VPD , stomatal conductance ( g s ), g s responses to VPD , mid-day minimum leaf water potential ( Ψ lmin ), and branch hydraulic architecture were taken in late June at four sites along the downstream of Tarim River at the north edge of the Taklamakan desert. We have found that: 1) the -m/b ratio was almost constant (=0.6) across all the sites; 2) the average Ψ 50 (the xylem water potential with 50% loss of hydraulic conductivity) was - 1.63 MPa, and mid-day PLC ranged from 62 to 83%; 3) there were tight correlations between Ψ 50 and wood density/leaf specific hydraulic conductivity ( k l ) and between specific hydraulic conductance sensitivity to water potential [d( k s )/dln( -Ψ )] and specific hydraulic conductivity ( k s ). A modified hydraulic model was applied to investigate the relationship between g s and VPD under variable Δ Ψ and K l conditions. It was concluded that P. euphratica was able to control PLC in order to maintain a relatively constant -m/b under different site conditions. This study demonstrated that branchlet hydraulic architecture and stomatal response to VPD were well coordinated in order to maintain relatively water homeostasis of P. euphratica in the desert. Model simulations could explain the wide variations of PLC across and within woody species that are often observed in the field., (Copyright © 2020 Fan, Dang, Xu, Jiang, Zhang, Xu, Yang and Zhang.)

Purpose: The aim of this study was to investigate the correlations and interactions between the polymorphisms of insulin resistance-related genes (ADIPOQ rs2241766), inflammation factors (TNF-α rs1800629, IL-6 rs1800795), obesity-related genes (GNB3 rs5443, ADRB rs1042714), and risk factors for gestational diabetes mellitus (GDM) such as diet structure in the development of GDM., Materials and Methods: This research was conducted among women who visited the third-affiliate hospital of Zhengzhou University for pregnancy checkups from 1 June 2014 to 30 December 2014. Based on the results of a 75-g glucose tolerance test (OGTT), 140 pregnant women with GDM were randomly selected as a part of the GDM group and140 healthy, pregnant women as part of the control group. Relevant clinical and laboratory data for the child and the mother including her pregnancy outcomes and the delivery mode were collected for the epidemiological survey., Results: The results showed that risk factors for GDM are advanced age, the hepatitis B virus, family history of diabetes, high body mass index before pregnancy, and weight gain of ≥10 kg before 24-week gestation. We found that diet structures were severely unbalanced. The polymorphisms rs2241766 and rs5443 were found to potentially be associated with GDM; moreover, a positive interaction was demonstrated between rs2241766 and age, and a negative interaction was demonstrated with weight gain of ≥10 kg before 24-week gestation., Conclusion: Our findings demonstrate that both environmental risk factors and genetic background contribute to the development of GDM.

Na + distribution is one of the most important strategies for plant resistance to salt stress. The way of Na + compartmentation in different aged leaves has been controversial, especially at the cell and sub-cellular level. The roles that Na + and K + /Na + play the key role in photosynthesis need to be further verified. In this study, using two cucumber cultivars Cucumis sativus L. cv. zhongnong 8 (ZN8, relatively salt tolerant) and Cucumis sativus L.cv. Jinchun 4 (JC4, salt sensitive) as experiment material, we analyzed the mode of ion compartmentation of Na + in organelles in different aged leaves and determined which factors (the organelles' Na + or K + /Na + ) affect leaf photosynthesis, using high-pressure freezing and freeze-substitution, Ultrathin sectioning technique and X-ray. The main results: 1. The sub-cellular trends of Na + accumulation was cell wall > vacuole > cytoplasm > chloroplasts; 2. The Na + accumulation in cytoplasm and chloroplasts was similar in different aged leaves and in seedlings of different salt tolerance cultivars; 3. The K + /Na + ratio is the main factor that affects the photosynthesis of the same aged leaves in our experiment. A weak capacity for ion compartmentation may be an important reason leading to salt sensitivity., (Copyright © 2018. Published by Elsevier Masson SAS.)

The objective of this study was to assess the genetic diversity and population structure of goats in the Yangtze River region using microsatellite and mtDNA to better understand the current status of those goat genetic diversity and the effects of natural landscape in fashion of domestic animal genetic diversity. The genetic variability of 16 goat populations in the littoral zone of the Yangtze River was estimated using 21 autosomal microsatellites, which revealed high diversity and genetic population clustering with a dispersed geographical distribution. A phylogenetic analysis of the mitochondrial D-loop region (482 bp) was conducted in 494 goats from the Yangtze River region. In total, 117 SNPs were reconstructed, and 173 haplotypes were identified, 94.5% of which belonged to lineages A and B. Lineages C, D, and G had lower frequencies (5.2%), and lineage F haplotypes were undetected. Several high-frequency haplotypes were shared by different ecogeographically distributed populations, and the close phylogenetic relationships among certain low-frequency haplotypes indicated the historical exchange of genetic material among these populations. In particular, the lineage G haplotype suggests that some west Asian goat genetic material may have been transferred to China via Muslim migration.

Dazu Black goat is an indigenous goat genetic resource in Southwest of China. Here, we describe its complete mitochondrial genome sequence. The mitogenome is 16,641 bp in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1% and G: 13.1%. The complete mitogenome of the indigenous goat could provide important data to further explore the taxonomic status of the subspecies and also provide a starting point for further phylogenetic studies.

Here, we describe the complete mitochondrial genome sequences of Jining Gray goat, Fushun black goat, Youzhou black-skin goat, and Hechuan white goat. The mitogenome of those four goats consisted of 16,640 nt, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. The complete mitogenome of these four local breeds of Chinese native goats could provide an important data to further breed improvement and animal genetics resource conservation in China.

The Hechuan white goat (Capra hircus), an indigenous of China. Here, we describe the complete mitochondrial genome sequence of Hechuan white goat. The mitogenome is 16,640 nt in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1% and G: 13.1%. The complete mitogenome of the local subspecies of Hechuan white goat could provide an important data to further explore the breed improvement in Chinese goat.

The Chuanzhong black goat (Capra hircus) is a breed native to southwest of China. Its complete mitochondrial genome is 16,641 nt in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and a non-coding control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1%, and G: 13.1%. The complete mitogenome of the Chinese indigenous breed of goat could provide a basic data for further phylogenetics analysis.

The Youzhou black-skin goat (Capra hircus), an indigenous breed of Chinese southwest. Here, we describe the complete mitochondrial genome sequence of Hechuan white goat. The mitogenome is 16,640 nt in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1% and G: 13.1%. The complete mitogenome of the local subspecies of Hechuan white goat could provide an important data to further breed improvement and animal genetics resource conservation in China.

Drought slows net photosynthetic rate (AN) but increases water use efficiency (WUE). Farmers give an artificial drought pretreatment to some crops in the early growth stage and find that yield increases accompanying with the improvement of WUE. We conducted well-watered, non-drought, mild drought and moderate drought pretreatments of potted cotton cultivars. The aims of the present study were to analyse the importance of mesophyll conductance (gm) as a factor that may simultaneously improve AN and WUE under drought pretreatment conditions, and to analyse the role of anatomical structure and biochemical mechanism in the variability of gm. Our results showed that significant variability of gm estimated by gas exchange and chlorophyll fluorescence was observed between non-drought pretreatment and drought pretreatment associated with change in AN and WUE. There was great difference in anatomical structure and expression of aquaporins (GhAQP1) among all the treatments. In addition, expression of carbonic anhydrase (CA) may not be important in the regulation of gm under drought pretreatment conditions. We concluded that the variability of gm offers a potential target for improving leaf AN and WUE simultaneously by the regulation of anatomical structure and GhAQP1., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

Desmoglein 4 (DSG4) has an important role in the development of wool traits in domestic animals. The full-length DSG4 gene, which contains 3918 bp, a complete open-reading-frame, and encodes a 1040-amino acid protein, was amplified from Liaoning cashmere goat. The sequence was compared with that of DSG4 from other animals and the results show that the DSG4 coding region is consistent with interspecies conservation. Thirteen single-nucleotide polymorphisms (SNPs) were identified in a highly variable region of DSG4, and one SNP (M-1, G>T) was significantly correlated with white and black coat color in goat. Haplotype distribution of the highly variable region of DSG4 was assessed in 179 individuals from seven goat breeds to investigate its association with coat color and its differentiation among populations. However, the lack of a signature result indicates DGS4 haplotypes related with the color of goat coat.

Reproducible methods for [(18)F]radiolabeling of biological vectors are essential for the development of new [(18)F]radiopharmaceuticals. Molecules such as carbohydrates, peptides and proteins are challenging substrates that often require multi-step indirect radiolabeling methods. With the goal of developing more robust, time saving, and less expensive procedures for indirect [(18)F]radiolabeling of such molecules, our group has synthesized ethynyl-4-[(18)F]fluorobenzene ([(18)F]2, [(18)F]EYFB) in a single step (14 ± 2% non-decay corrected radiochemical yield (ndc RCY)) from a readily synthesized, shelf stable, inexpensive precursor. The alkyne-functionalized synthon [(18)F]2 was then conjugated to two azido-functionalized vector molecules via CuAAC reactions. The first 'proof of principle' conjugation of [(18)F]2 to 1-azido-1-deoxy-β-D-glucopyranoside (3) gave the desired radiolabeled product [(18)F]4 in excellent radiochemical yield (76 ± 4% ndc RCY (11% overall)). As a second example, the conjugation of [(18)F]2 to matrix-metalloproteinase inhibitor (5), which has potential in tumor imaging, gave the radiolabeled product [(18)F]6 in very good radiochemical yield (56 ± 12% ndc RCY (8% overall)). Total preparation time for [(18)F]4 and [(18)F]6 including [(18)F]F(-) drying, two-step reaction (nucleophilic substitution and CuAAC conjugation), two HPLC purifications, and two solid phase extractions did not exceed 70 min. The radiochemical purity of synthon [(18)F]2 and the conjugated products, [(18)F]4 and [(18)F]6, were all greater than 98%. The specific activities of [(18)F]2 and [(18)F]6 were low, 5.97 and 0.17 MBq nmol(-1), respectively., (Copyright © 2015 John Wiley & Sons, Ltd.)

This study reports the synthesis, [(123)I]radiolabeling, and biological profile of a new series of iodinated compounds for potential translation to the corresponding [(131)I]radiolabeled compounds for radionuclide therapy of melanoma. Radiolabeling was achieved via standard electrophilic iododestannylation in 60-90% radiochemical yield. Preliminary SPECT imaging demonstrated high and distinct tumor uptake of all compounds, as well as high tumor-to-background ratios compared to the literature compound [(123)I]4 (ICF01012). The most favorable compounds ([(123)I]20, [(123)I]23, [(123)I]41, and [(123)I]53) were selected for further biological investigation. Biodistribution studies indicated that all four compounds bound to melanin containing tissue with low in vivo deiodination; [(123)I]20 and [(123)I]53 in particular displayed high and prolonged tumor uptake (13% ID/g at 48 h). [(123)I]53 had the most favorable overall profile of the cumulative uptake over time of radiosensitive organs. Metabolite analysis of the four radiotracers found [(123)I]41 and [(123)I]53 to be the most favorable, displaying high and prolonged amounts of intact tracer in melanin containing tissues, suggesting melanin specific binding. Results herein suggest that compound [(123)I]53 displays favorable in vivo pharmacokinetics and stability and hence is an ideal candidate to proceed with further preclinical [(131)I] therapeutic evaluation.

During leaf development, the increase in stomatal conductance cannot meet photosynthetic demand for CO2, thus leading to stomatal limitation of photosynthesis (Ls). Considering the crucial influences of stomatal development on stomatal conductance, we speculated whether stomatal development limits photosynthesis to some extent. To test this hypothesis, stomatal development, stomatal conductance and photosynthesis were carefully studied in both Syringa oblata (normal greening species) and Euonymus japonicus Thunb (delayed greening species). Our results show that the size of stomata increased gradually with leaf expansion, resulting in increased stomatal conductance up to the time of full leaf expansion. During this process, photosynthesis also increased steadily. Compared to that in S. oblata, the development of chloroplasts in E. japonicus Thunb was obviously delayed, leading to a delay in the improvement of photosynthetic capacity. Further analysis revealed that before full leaf expansion, stomatal limitation increased rapidly in both S. oblata and E. japonicus Thunb; after full leaf expansion, stomatal limitation continually increased in E. japonicus Thunb. Accordingly, we suggested that the enhancement of photosynthetic capacity is the main factor leading to stomatal limitation during leaf development but that stomatal development can alleviate stomatal limitation with the increase of photosynthesis by controlling gas exchange., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

In the field, close planting inevitably causes mutual shading and depression of leaf photosynthesis. To clarify the regulative mechanisms of photosynthesis under these conditions, the effects of planting density on leaf structure, gas exchange and proteomics were carefully studied in field-grown sorghum. In the absence of mineral deficiency, (1) close planting induced a significant decrease in light intensity within populations, which further resulted in much lower stomatal density and other anatomical characteristics associated with shaded leaves; (2) sorghum grown at high planting density had a lower net photosynthetic rate and stomatal conductance than those grown at low planting density; (3) approximately 62 protein spots changed their expression levels under the high planting density conditions, and 22 proteins associated with photosynthesis were identified by mass spectrometry. Further analysis revealed the depression of photosynthesis caused by mutual shading involves the regulation of leaf structure, absorption and transportation of CO2, photosynthetic electron transport, production of assimilatory power, and levels of enzymes related to the Calvin cycle. Additionally, heat shock protein and oxygen-evolving enhancer protein play important roles in photoprotection in field-grown sorghum. A model for the regulation of photosynthesis under mutual shading was suggested based on our results., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)

Imprinted genes play significant roles in the regulation of fetal growth and development, function of the placenta, and maternal nurturing behaviour in mammals. At present, few imprinted genes have been reported in pigs compared to human and mouse. In order to increase understanding of imprinted genes in swine, a polymorphism-based approach was used to assess the imprinting status of three porcine genes in 12 tissue types, obtained from F1 pigs of reciprocal crosses between Rongchang and Landrace pure breeds. In contrast to human and mouse homologues, porcine PPP1R9A was not imprinted, and was found to be expressed in all tissues examined. The expression of porcine NAP1L5 was detected in pituitary, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, ovary, and uterus, but undetectable in heart. Furthermore, porcine NAP1L5 was paternally expressed in the tissues where it's expression was observed. For PEG3, pigs expressed the paternal allele in skeletal muscle, liver, spleen, kidney, and uterus, but biallele in heart, lung, fat, stomach, small intestine, and ovary. Our data indicate that tissue distribution of the three gene differs among mammals, and the imprinting of NAP1L5 and PEG3 is well conserved.

Leaf anatomy of C3 plants is mainly regulated by a systemic irradiance signal. Since the anatomical features of C4 plants are different from that of C3 plants, we investigated whether the systemic irradiance signal regulates leaf anatomical structure and photosynthetic performance in sorghum (Sorghum bicolor), a C4 plant. Compared with growth under ambient conditions (A), no significant changes in anatomical structure were observed in newly developed leaves by shading young leaves alone (YS). Shading mature leaves (MS) or whole plants (S), on the other hand, caused shade-leaf anatomy in newly developed leaves. By contrast, chloroplast ultrastructure in developing leaves depended only on their local light conditions. Functionally, shading young leaves alone had little effect on their net photosynthetic capacity and stomatal conductance, but shading mature leaves or whole plants significantly decreased these two parameters in newly developed leaves. Specifically, the net photosynthetic rate in newly developed leaves exhibited a positive linear correlation with that of mature leaves, as did stomatal conductance. In MS and S treatments, newly developed leaves exhibited severe photoinhibition under high light. By contrast, newly developed leaves in A and YS treatments were more resistant to high light relative to those in MS- and S-treated seedlings. We suggest that (1) leaf anatomical structure, photosynthetic capacity, and high-light tolerance in newly developed sorghum leaves were regulated by a systemic irradiance signal from mature leaves; and (2) chloroplast ultrastructure only weakly influenced the development of photosynthetic capacity and high-light tolerance. The potential significance of the regulation by a systemic irradiance signal is discussed.

Objective: To explore the correlation between the elevated expression of cytokines under the induction of Poly(I:C) (polycytidylic acid) in maternal hosts and the abnormal behaviors of adult offsprings and understand the intervening effects of nuclear factor NF-κB inhibitor pyrrolidinedithiocarbamate (PDTC)., Methods: Poly(I:C) or saline was administered to model the maternal infection during early pregnancy in rats. And the expression of cytokines was blocked with PDTC. The maternal levels of tumor necrosis factor alpha and interleukin-10 were determined by ELISA (enzyme-linked immunosorbent assay). The adult offsprings on different treatments were then compared with regards to prepulse inhibition (PPI), passive avoidance and active avoidance., Results: After the administration of Poly(I:C), there was an elevated levels of serum cytokines as shown by the markedly increased serum levels of IL-10 and TNF-α. The serum levels of IL-10 and TNF-α in the model group were significantly higher than those in the control group [(18.26 ± 1.52) pg/ml, (119.64 ± 16.42) pg/ml vs. (0.16 ± 0.13) pg/ml and (11.21 ± 1.81) pg/ml]. The elevation was partly blocked by PDTC. The serum levels of IL-10 and TNF-α in the intervention group [(12.64 ± 2.04) pg/ml and (30.34 ± 2.19) pg/ml respectively] were lower than those in the model group, but still higher than those in the control group. The psychotic-like phenotypes including defects in PPI, passive avoidance and active avoidance were observed in Poly(I:C)-treated offsprings. Such an effect was blunted by the PDTC intervention. The PPI results demonstrated that the PP₂ and PP₈ difference between rats in 3 groups were statistically significant, with a lower PPI value in the model group than in the intervention group, in the intervention group than in the control group and much lower in the model group than in the control group. PP4 was lower in the model group than that in the intervention group, and also lower in the model group than in the control group. There was no significant difference between the control group and the intervention group. The passive avoidance results indicated that T1 was higher in the model group than in the control and intervention groups and there was no statistical difference between the control and intervention groups. T2 was lower in the model group than in the control and intervention groups and there was no statistical difference between the control and intervention groups. And the active avoidance test results showed that total conditioned reflex times of the control group was higher than those of the intervention and model groups. No statistical difference was found between the intervention and model groups. Total reflex rate of the control group was higher than that of the intervention and model groups. No statistical difference was found between the intervention and model groups., Conclusion: PDTC can interfere with neural developmental disorder of adult offsprings through blunting the cytokine-mediated maternal immune response.

To explore the mechanisms underlying water regulation in clonal plants and its effects on carbon assimilation under water stress, we studied the responses of water status, gas exchange and abscisic acid (ABA) contents to water stress in leaves of pairs of strawberry ramets that consist of mother and daughter ramets. There was a greater decrease in photosynthetic rates (P(n)) and stomatal conductance (G(s)) in the disconnected mother ramets than the connected mother ramets upon exposure to water stress, indicating that water stress in mother ramets was alleviated by water translocation from the well-watered daughter ramets. Conversely, the connected mother ramets displayed enhanced symptoms of water stress when the connected daughter ramets were exposed to water deficit. The mother ramets had lower water potential (psi(w)) due to their stronger osmotic adjustment than in well-watered daughter ramets; this resulted in water flow from the connected daughter ramets to mother ramets, thus alleviating water stress of mother ramets. During soil drying, there was a striking increase in ABA concentrations in leaves of the disconnected mother ramets, whereas leaf bulk ABA was much lower in the connected and water-stressed mother ramets than that in the drought-affected mother ramets in the disconnected group. In this study, though G(s) was linearly correlated with leaf bulk ABA and psi(w), G(s) in water-stressed mother ramets in disconnected group exhibited less sensitivity to the variation in leaf bulk ABA and psi(w) than that in connected and water-stressed mother ramets. Taken together, these results indicate that: (1) the flux of water translocation between the connected ramets is determined by a water potential gradient; (2) water translocation between connected ramets helps to keep sensitivity of G(s) to ABA and psi(w) in drought-affected ramets, thereby benefit to effectively maintain the homeostasis of leaf water status and (3) the improvements in P(n) in water-stressed ramets due to water translocation from well-watered ramets suggest the advantages of physiological integration in clonal plants in environments with heterogeneous water distribution.

Imprinted genes play important roles in mammalian growth and development. However, reports on imprinted genes are limited in livestock. In this study, the complete ORF containing 289 amino acids of the porcine DLX5 gene was obtained. A C-to-T SNP mutation in exon 1 of the DLX5 gene was used to detect imprinting status with an RT-PCR/RFLP test (using HhaI) in eight heterozygous pigs from a population of Large White x Meishan F(1) hybrids. Imprinting analysis showed that the porcine DLX5 gene was maternally expressed in skeletal muscle, fat, lung, spleen, stomach and small intestine, but not imprinted in heart, liver, kidney, uterus, ovary, testicle or pituitary. A PCR-RFLP test was also used to detect the polymorphism in 310 pigs of a Large White x Meishan F(2) resource population. The statistical results showed significant association (P < 0.01) of the genotypes and fat meat percentage, carcass length, bone percentage, 6-7 rib fat thickness, average backfat thickness, thorax-waist fat thickness and buttock fat thickness.

Allelopathy of Ageratina adenophora plays an important role in its invasion. However, we have little knowledge of its allelpathic effects on ferns. In Petri dish bioassays, the inhibitory potential of aqueous leachates from roots, stems and leaves of A. adenophora was studied on the spore germination and gametophyte development of Macrothelypteris torresiana. All leachates inhibited the spore germination and growth of the first rhizoid of M. torresiana and inhibitory effects increased with increasing leachate concentrations. Root leachates proved most inhibitory. Gametophyte rhizoids of M. torresiana treated with stem and leaf leachates of A. adenophora were erect, which was similar to those of the control. However, gametophyte rhizoids of M. torresiana treated with root leachates of A. adenophora were erect, but also curving or swollen. Moreover, curving and swollen rhizoids increased with increasing concentrations. As time went by, rhizoids treated with root leachates were not so curved and the swelling almost disappeared. Possible causes are discussed in the present study. The increasing concentrations of leaf leachates also delayed the stages of gametophyte development. With the treatment of root leachates, the delay was more obvious. Thus A. adenophora inhibited the spore germination and gametophyte development of M. torresiana and the root leachates were most inhibitory.

Although expression and epigenetic differences of imprinted genes have been extensively characterised in man and the mouse, little is known on livestock species. In this study, the polymorphism-based approach was used to detect the imprinting status of NNAT and DIRAS3 genes in five heterozygous pigs (based on SNP) of Large White and Meishan F(1) hybrids. The results show that both genes were paternally expressed in all the tested tissues (heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, uterus, ovary and pituitary). In addition, the NNAT gene had two transcripts in all tested tissues, which is consistent with its counterpart in man and cattle.

Genomic imprinting is theorized to exist in all placental mammals and some marsupials. Imprinted genes play important roles in the regulation of fetal growth, development, and postnatal behavior, but the study of imprinted genes has been limited in livestock. In this study, the polymorphism-based approach was used to detect the expression patterns of the porcine pleomorphic adenoma gene-like I (PLAGL1) and paternal expression gene 10 (PEG10) genes. Single nucleotide polymorphisms in the exons were detected between the Meishan and Large White breeds in the PLAGL1 and PEG10 genes. The polymorphisms were used to determine the monoallelic or biallelic expression with reverse transcription-PCR-RFLP in 44 tissues from 4 heterozygous pigs (based on SNP). Imprinting analysis indicated that the PLAGL1 and PEG10 genes were both paternally expressed in all tissues tested (heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, uterus, and ovary). Our study showed that the method of identifying polymorphic transcripts with reverse transcription-PCR-RFLP may be beneficial for detecting the imprinting status of some candidate imprinted genes.

Gas exchange and chlorophyll a fluorescence in soybean plants were investigated to explore the effects of iron deficiency on photosynthesis and photosystem II function in vivo. Iron deficiency induced a drastic decrease in net photosynthesis (Pn). Compared with normal plants, the maximal quantum yield of PSII photochemistry (psipo) in iron-deficient plants was only slightly lower; whereas, the efficiency with which a trapped exciton can move an electron into the electron transport chain further than QA-(Psio) and quantum yield of electron transport beyond QA (psiEo) were significantly depressed. Iron deficiency also caused a clear enhancement of the relative variable fluorescence at K step (VK). When exposed to light, iron-deficient plants had considerably lower efficiency of excitation energy capture by open PSII reaction centers (Fv'/Fm'), quantum yield of PSII electron transport (PhiPSII), and photochemical quenching coefficient (qP), but markedly higher non-photochemical quenching (NPQ). In addition, post-illumination transient increase in chlorophyll fluorescence was clearly enhanced in iron-deficient plants. Basing on these data, we suggest that both the donor and the acceptor sides of PSII complex were damaged by iron deficiency; cyclic electron transport around PSI in iron-deficient soybean plants might play an important role in inducing the excitation energy dissipation and meeting the demand for extra ATP as a compensation for the loss of phosphorylation capability.

Gas exchange, chlorophyll a fluorescence and HPLC analysis were used to explore photosynthesis and dissipation of excited energy in soybean leaves from emergence to full development. During leaf development, both photosynthetic rate and stomata conductance increased gradually, whereas the increase in stomata conductance significantly lagged behind that of photosynthetic rate. Considering stomatal limiting value, it can be easily deduced that photosynthesis was considerably limited by low stomatal conductance during leaf development. Though the maximum quantum yield of photosystem II (PSII) photochemistry (F(v)/F(m)) was quite high at the stages of leaf development, it is appreciably lower than that in fully developed leaves. Reversible decrease in F(v)/F(m) occurred caused by high irradiance during daily courses at all stages of leaf development, indicating that no severe photoinhibition occurred when exposed to high light. Under high irradiance, a substantial increase in the actual PSII efficiency (Phi(PSII)) together with a marked decreased in non-photochemical quenching (NPQ) occurred during the process of leaf development. Compared with the values obtained at 9:00 AM, Phi(PSII) in developing leaves was drastically down-regulated after midday, whereas NPQ was enhanced significantly. Compared with fully expanded leaves, those developing leaves, with higher xanthophyll pool size, exhibited a much higher ratio of zeaxanthin (Z) + antheraxanthin (A) to Chl under irradiation. In addition, the relative xanthophyll pool size (V+A+Z)/Chl was found to decrease with leaf development. Our experiments revealed that the decline of xanthophyll cycle pool during leaf development was due to the fact that the chlorophyll content increased faster than the xanthophyll cycle pigment content. We suggest that as soon as leaf emerged, photoprotective mechanism was developed preferentially which can effectively protect leaves against excessive irradiance. Thermal dissipation depending on xanthophyll cycle is a very important photoprotective mechanism for dealing with high irradiance during leaf development.

The genetic variation of Meishan, Huainan, Tongcheng, Bamei, Hezuo and Largewhite pigs were analyzed by RAPD markers. Twenty-four single polymorphic primers were selected out of 276 primers by amplifying six pool DNA. The index of Shannon were 0.178672, 0.17781,0.15995, 0.14549,0.16949, 0.14159 respectively; Hpop was 0.16216, Hsp was 0.2534. The phylogenetic tree was constructed using NJ and UPGMA. The results indicated that the phenylogenetic relationship of the six pig breeds was consistent with their distribution.