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Summary 1. Herba Leonuri, a traditional Chinese medicine, has a long history of development and application in China. In particular, Herba Leonuri has been widely used in the treatment of gynaecological and obstetric disorders for thousands of years. Recent studies have shown that Herba Leonuri has many different effects. 2. Herba Leonuri contains several active components, including alkaloids, flavonoids, diterpenes compounds and fatty acids. Recent studies have shown that these molecules exert beneficial effects in coronary artery disease and cerebral ischaemia. Thus, these molecules may become novel candidates for drug discovery and development. 3. The present review provides an overview of the chemical composition, with a focus on biological activity, of Herba Leonuri to stimulate new studies on traditional Chinese medicine.

SUMMARY. Highly pathogenic avian influenza viruses of the subtype H5N1 (HPAIV-H5N1) have circulated continuously in Asia, Europe, and Africa since 2003. Investigations on the environmental preference and global spread processes of the virus are needed. We compiled 16 environmental variables to assess their correlation with HPAIV-H5N1 occurrences by using a niche-based model called Maxent. We found the virus had the strongest positive association with the human footprint index, as well as the presence of certain types of wetlands and mild temperature (10–30 C). Outbreaks of HPAIV-H5N1 in poultry or wild birds were also more frequent in certain major habitat types (e.g., tropical and subtropical moist broadleaf forests, temperate broadleaf and mixed forests, and flooded grasslands and savannas) and ecoregions. We conducted trend surface analysis to generate the travelling wave of the virus' global spread from 2003 to 2009, which indicated that high mountains or plateaus did not affect the spread speed and d...

Nitration of aromatics is one of the most broadly studied and famous non-selective organic reaction which provides key organic intermediates or energetic materials. However, the industrial syntheses of nitro compounds suffer many disadvantages: employing large quantities of sulfuric acids as catalysis, which may generate acid waste that is expensive to dispose off, over nitration, low selectivity, oxidation byproducts and safety problems. Major efforts have therefore been made to dispense the use of sulfuric acid for the aromatic nitration and develop environmentally benign and clean processes to replace conventional nitration. The nitro derivatives of biphenyl are used as intermediates for the preparation of fragrance, dyes, plasticizer and polymer. The earlier attempts of nitration of biphenyl derivatives have been made by using nitric acid and sulfuric acid or acetic anhydride as the nitrating mixture gives a mixture of 4-nitrobiphenyl and 2-nitrobiphenyl. Recently, many new methods of the nitration of biphenyl were reported. However, few of them mentioned about the di-nitration of biphenyl. Thus, it is necessary to develop a clean and commercial process for the selective di-nitration of biphenyl in high conversion and yield. In pursuit of our former efforts on nitration of toluene, chlorobenzene, naphthalene and biphenyl using zeolite catalysts, we hope to improve the selectivity and yield in the di-nitration of biphenyl by the use of zeolite. Catalysts always play an important role in the kinetics of chemical reactions, thereby influencing the selectivity of a desired isomer directly. Zeolites have well-defined pore structures and channels that are derived from the networking of SiO2 and Al2O3 making them attractive candidates for shape selective catalysis. To optimize the reaction time for maximum di-nitration yield, samples were analyzed at varied time ranging from 1 to 24 h. The main data (Table 1) showed that the highest dinitration yield was obtained at 24 h with HBEA-500 (0.3 g) zeolite as a catalyst. Zeolites facilitated the reaction and gave a high di-nitration yield as compared with no catalyst (Entry 1 Table 1). With the Si/Al ratio increasing of HBEA zeolite catalyst, a high ratio of formation of 4,4'-dinitrobiphenyl 3c was favored (Entries 3-8, from Table 1). HBEA zeolite catalyst with a low Si/Al ratio showed a worse selectivity for 3c than that of high Si/Al ratio possibly because of the dealuminiation, which would modify the distribution of the size and shape of the pores in zeolites. The average particle sizes of the HBEA zeolites decrease with Si/Al ratio which was detected from the SEM images. High alumina containing zeolites show a very-hydrophilic character, whereas, high

Recently, the one-stage posterior approach for treating spinal tuberculosis (TB) has gained popularity. However, large bony defects after debridement remain a major challenge in posterior surgery. The present retrospective study aims to compare the clinical outcomes of posterior-only surgical management by titanium mesh versus iliac bone grafts for treating lumbosacral TB. This was a retrospective cohort study. From January 2006 to April 2012, 36 patients with lumbosacral TB were treated at our department. The 36 cases were divided into 2 groups: 17 patients in Group A (titanium mesh) underwent one-stage posterior internal fixation, debridement, and titanium mesh bone fusion. The 19 patients in Group B (iliac bone graft) underwent posterior instrumentation, debridement, and iliac bone graft in a single procedure. The clinical and radiographic results for the 2 groups were analyzed and compared. The mean year of patients was 49.9 ± 15.4 months in group A and 55.5 ± 12.6 months in group B. All patients were followed up for an average of 47.3 ± 8.1 months (range 36-60 months). Spinal TB was completely cured and no intraspinal infection and central nervous system complications of TB infection occurred. Bone fusion was achieved 6.4 ± 1.9 months in group A and 7.8 ± 2.1 months in group B. There was no significant statistical difference in bone fusion between the 2 groups (P > .05). The Oswestry Disability Index score (ODI) significantly improved between the preoperative and the last visit in either group. However, no significant difference was observed between the 2 groups at last visit (P > .05). There were significant differences between groups regarding the postoperative lumbosacral angle and angle correction loss at the final follow-up (P < .05). The average operative complication rate of Group A was less than that of Group B. Both iliac bone and titanium mesh can effectively construct anterior column defects in posterior surgery. The titanium mesh has the advantage of minor surgical invasion, effective reconstruction of large defects, and ideal sagittal alignment in lumbosacral TB for patients with osteoporosis and poor iliac bone quality.

This paper describes the research about the beta -cyclodextrin influence on Vibrio fischeri toxicity of 10 phenylsulfonyl carboxylates. It is illustrated that the formation of 1:1 cyclodextrin-solute inclusion complexes dominates the toxicity influence of phenylsulfonyl carboxylates to Vibrio fischeri and greatly weakens the toxicity level. Using the octanol-water partition coefficients lg KOW, the grouped electrotopological state (E-state) index S(SO2) and the stability constants of inclusion complexes lg KS, three models with high squared correlation coefficients r2adj at 0.908, 0.951 and 0.917, respectively were constructed to evaluate the beta-cyclodextrin influence on Vibrio fischeri toxicity. For the type of phenylsulfonyl carboxylates, the inclusion stability constants lg KS can reliably model and predict the beta-cyclodextrin influence on Vibrio fischeri toxicity (TI).

Since 1986, the reference of birth weight for gestational age has not been updated. The aim of this study was to set up Chinese neonatal network to investigate the current situation of birth weight in China, especially preterm birth weight, to develop the new reference for birth weight for gestational age and birth weight curve.A nationwide neonatology network was established in China. This survey was carried out in 63 hospitals of 23 provinces, municipalities and autonomous regions. We continuously collected the information of live births in participating hospitals during the study period of 2011-2014. Data describing birth weight and gestational age were collected prospectively. Newborn's birth weight was measured by electronic scale within 2 hours after birth when baby was undressed. The evaluation of gestational age was based on the combination of mother's last menstrual period, ultrasound in first trimester and gestational age estimation by gestational age scoring system.the growth curve was drawn by using LMSP method, which was conducted in GAMLSS 1.9-4 software package in R software 2.11.1.A total of 159 334 newborn infants were enrolled in this study. There were 84 447 male and 74 907 female. The mean birth weight was (3 232 ± 555) g, the mean birth weight of male newborn was (3 271 ± 576) g, the mean weight of female newborn was (3 188 ± 528) g. The test of the variables' distribution suggested that the distribution of gestational age and birth weight did not fit the normal distribution, the optimal distribution for them was BCT distribution. The Q-Q plot test and worm plot test suggested that this curve fitted the distribution optimally. The male and female neonatal birth weight curve was developed using the same method.Using GAMLSS method to establish nationwide neonatal birth weight curve, and the first time to update the birth weight reference in recent 28 years.

Analog-to-digital converters (ADCs) with large signal bandwidth (BW) and high resolution are needed for communication applications, e.g. base-station receivers. The continuous-time (CT) sigma-delta ADC [1] is a promising candidate for such applications because of its simple resistive input and inherent anti-aliasing filtering. In the design of high-speed CT sigma-delta ADC, the delay of the comparator and feedback DAC, which is referred to as excess loop delay (ELD), should be compensated with an extra high-speed feedback path [2]. A summation function of the ELD compensation feedback signal and the feed-forward signal from the loop filter’s output needs to be implemented. This poster will show a comparison between two possible circuit-level approaches for this summation function – current summation [3] and capacitive summation. The purpose of this research is to compare both approaches mainly with respect to accuracy, power efficiency, and circuit complexity. To make a fair and quantitative comparison, an ideal register transfer level (RTL) 3rd-order 1bit CT sigma-delta ADC with several GSample/s sampling rate is synthesized and used as a common test bench. Both current and capacitive summation methods are implemented at transistor-level and optimized for the same resolution and signal bandwidth targets. Circuit-level non-idealities such as parasitic capacitance and mismatch are considered. The power consumption of both methods is analyzed and optimized for the same resolution target. Simulation results show that both methods can meet the resolution target, but for this speed and resolution current summation has a better power efficiency.

International audience

Doubly uniparental inheritance (DUI) of mitochondrial DNA, found only in some bivalve families and characterized by the existence of gender-associated mtDNA lineages that are inherited through males (M-type) or females (F-type), is one of the very few exceptions to the general rule of strict maternal mtDNA inheritance in animals. M-type sequences are often undetected and hence still underrepresented in the GenBank, which hinders the progress of the understanding of the DUI phenomenon. We have sequenced and analyzed the complete M and F mitogenomes of a freshwater mussel, Potamilus alatus. The M-type was 493 bp longer (M = 16 560, F = 16 067 bp). Gene contents, order and the distribution of genes between L and H strands were typical for unionid mussels. Candidates for the two ORFan genes (forf and morf) were found in respective mitogenomes. Both mitogenomes had a very similar A+T bias: F = 61% and M = 62.2%. The M mitogenome-specific cox2 extension (144 bp) is much shorter than in other sequenced unionid mitogenomes (531-576 bp), which might be characteristic for the Potamilus genus. The overall topology of the phylogenetic tree is in very good agreement with the currently accepted phylogenetic relationships within the Unionidae: both studied sequences were placed within the Ambleminae subfamily clusters in the corresponding M and F clades.

Nitration of aromatics is one of the most broadly studied and famous non-selective organic reaction which provides key organic intermediates or energetic materials. However, the industrial syntheses of nitro compounds suffer many disadvantages: employing large quantities of sulfuric acids as catalysis, which may generate acid waste that is expensive to dispose off, over nitration, low selectivity, oxidation byproducts and safety problems. Major efforts have therefore been made to dispense the use of sulfuric acid for the aromatic nitration and develop environmentally benign and clean processes to replace conventional nitration. The nitro derivatives of biphenyl are used as intermediates for the preparation of fragrance, dyes, plasticizer and polymer. The earlier attempts of nitration of biphenyl derivatives have been made by using nitric acid and sulfuric acid or acetic anhydride as the nitrating mixture gives a mixture of 4-nitrobiphenyl and 2-nitrobiphenyl. Recently, many new methods of the nitration of biphenyl were reported. However, few of them mentioned about the di-nitration of biphenyl. Thus, it is necessary to develop a clean and commercial process for the selective di-nitration of biphenyl in high conversion and yield. In pursuit of our former efforts on nitration of toluene, chlorobenzene, naphthalene and biphenyl using zeolite catalysts, we hope to improve the selectivity and yield in the di-nitration of biphenyl by the use of zeolite. Catalysts always play an important role in the kinetics of chemical reactions, thereby influencing the selectivity of a desired isomer directly. Zeolites have well-defined pore structures and channels that are derived from the networking of SiO2 and Al2O3 making them attractive candidates for shape selective catalysis. To optimize the reaction time for maximum di-nitration yield, samples were analyzed at varied time ranging from 1 to 24 h. The main data (Table 1) showed that the highest dinitration yield was obtained at 24 h with HBEA-500 (0.3 g) zeolite as a catalyst. Zeolites facilitated the reaction and gave a high di-nitration yield as compared with no catalyst (Entry 1 Table 1). With the Si/Al ratio increasing of HBEA zeolite catalyst, a high ratio of formation of 4,4'-dinitrobiphenyl 3c was favored (Entries 3-8, from Table 1). HBEA zeolite catalyst with a low Si/Al ratio showed a worse selectivity for 3c than that of high Si/Al ratio possibly because of the dealuminiation, which would modify the distribution of the size and shape of the pores in zeolites. The average particle sizes of the HBEA zeolites decrease with Si/Al ratio which was detected from the SEM images. High alumina containing zeolites show a very-hydrophilic character, whereas, high

The North American pink heelsplitter (Potamilus alatus) differs from most freshwater mussels in China by the ability to secrete an ephemeral byssus during its juvenile stage. In the present study, light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to investigate this ephemeral byssal structure, and amino acid composition was analyzed and compared with that of other species. The results revealed that the byssus consists of a long byssal thread and a few adhesive plaques which are randomly set up along the thread and assembled by petioles. There is a thin but distinctive cuticle with a continuous homogeneous matrix surrounding the byssal thread. Structural variation occurred when the byssal thread was differentially stretched. Four-stranded helical primary fasciculi, which form a stable rope-like structure, become evident after removal of the cuticle. The primary fasciculi consist of bundles of hundreds of parallel secondary fasciculi, each measuring about 5 μm in diameter. All evidence indicates that the byssus of the pink heelsplitter has a significantly different macrostructure and microstructure than the permanent byssus of the marine mussel Mytilus. Byssogenesis ceases when juveniles exceed 30 mm in length, although it varies greatly even among juveniles of similar size. Byssus formation is influenced by substrate type. The unique characteristics of the byssus have important advantages for survival, transition, and aggregation during the early life history. This study not only provides first insight into the structure of the ephemeral byssus and its relationship to freshwater mussel development and growth, but also suggests possibilities for the synthesis of novel biopolymer materials particularly useful in freshwater ecosystems.

The use of psoralens combined with exposure to ultraviolet A radiation is a major form of treatment for psoriasis and a number of other common skin diseases. Although psoralen plus ultraviolet A treatment is highly effective, careful follow-up cohort studies have shown that it greatly increases risk for the development of cutaneous squamous cell carcinoma and melanoma. Strategies to reduce the risk of cancer development in psoralen plus ultraviolet A-treated populations are highly desirable. In prior studies, we demonstrated that green tea and constituent polyphenols protect against ultraviolet B-induced carcinogenesis and reduce the growth rate of established tumors in skin. In this study, we show that pre- and post-treatment with standardized green tea extract in psoralen plus ultraviolet A treatment populations abrogates the psoralen plus ultraviolet A-induced photochemical damage to skin. Intact mouse and human skin and reconstituted human skin were employed to assess the effect of both topical and oral administration of standardized green tea extract against psoralen plus ultraviolet A-induced photodamage. Oral administration of standardized green tea extract prior to and during multiple psoralen plus ultraviolet A treatments reduced hyperplasia and hyperkeratosis in murine skin. Standardized green tea extract treatment also inhibited accumulation of c-fos and p53 protein induction following a single exposure to psoralen plus ultraviolet A. c-fos and p53 positive cells in psoralen plus ultraviolet A-treated skin were found to be increased by 55.4 ± 13.6% and 62.3 ± 10.5%, respectively, compared with saline-treated unexposed control skin. Oral administration of 0.4 or 0.8% standardized green tea extract inhibited c-fos protein accumulation by 18.5% and 46.2% (p < 0.05), respectively, and p53 protein accumulation by 26.1% and 54.3% (p < 0.05), respectively. Similarly proliferating cell nuclear antigen staining, a marker of cell proliferation was induced (73.7%) in psoralen plus ultraviolet A-treated skin. Oral administration of 0.4% or 0.8% standardized green tea extract 1 d after psoralen plus ultraviolet A treatment was effective in reducing psoralen plus ultraviolet A-induced inflammatory responses including erythema and edema formation. When standardized green tea extract was applied to EpiDerm, a reconstituted human skin equivalent, psoralen plus ultraviolet A-induced 8-methoxypsoralen-DNA adduct formation and p53 protein accumulation were inhibited. Topical application of 0.2 mg 8-methoxypsoralen per cm2 followed by exposure to ultraviolet A (2.5 J per cm2) resulted in delayed erythema formation in human subjects. Pretreatment of human skin with topical application of 0.2 mg standardized green tea extract per cm2 30 min prior to psoralen plus ultraviolet A treatment resulted in an almost complete abrogation of psoralen plus ultraviolet A-induced erythema. In summary, these data demonstrate that standardized green tea extract protects against psoralen plus ultraviolet A-induced phototoxicity by inhibiting DNA damage and diminishing the inflammatory effects of this modality.

EpiDerm (MatTek Co., MA) is a reconstituted human skin equivalent which exhibits morphological and growth characteristics similar to human skin. This model has previously been utilized to evaluate the cytotoxicity and irritant potential of various cosmetic and household products. In this study, we show for the first time that EpiDerm can be used successfully to evaluate the genotoxicity of different types of known carcinogenic agents such as benzo[a]pyrene (BaP), ultraviolet B radiation (UVB), ultraviolet A radiation (UVA), and psoralen-ultraviolet A radiation (PUVA) at the molecular level. The topical application of 50 microg/cm2 BaP to EpiDerm resulted in the accumulation of BaP-DNA adducts and c-fos and p53 proteins as evidenced by immunohistochemical localization. Similarly, exposure to UVB (50 mJ/cm2) and UVA (2.5 J/cm2) enhanced the epidermal expression of c-fos and p53 proteins in the human skin equivalent. PUVA treatment of EpiDerm, however, resulted in the formation of both DNA-8-MOP adducts and augmented expression of c-fos and p53 proteins. Most of these changes reached a peak 8 h after the treatments except in the case of UVA where maximum changes in the expression of c-fos and p53 proteins were observed 24 h after treatment. These results are similar to those previously reported in human and murine skin following exposure to BaP, UVB, UVA, or PUVA indicating that human skin equivalents can be used as a convenient and cost-effective alternative to animal testing for assessing the genotoxicity and mechanism of action of mutagens/carcinogens in human skin.