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Two new flavanoids fissistiganoids A and B (1 and 2), together with two known pterocarpans derivatives (3 and 4), were isolated from the stems of Fissistigma tungfangense. The structures of these compounds were elucidated using comprehensive spectroscopic methods. The absolute configurations of fissistiganoids A and B (1 and 2) were determined by comparing their ECD spectra with quantum-mechanics ECD calculations. The inhibitory activities of all compounds against three cancer cell lines HeLa, MCF-7 and A549 were evaluated. Compounds 1–4 showed moderate inhibitory effects on HeLa, MCF-7 and A549 cells with IC50 values ranging from 12.5 to 42.3 μM.

Intermolecular cycloaddition of tosylhydrazones with nitriles was investigated. t-BuOK was shown to be an excellent base for increasing the effectiveness of the reaction in this protocol, and homocoupling of the tosylhydrazones was significantly inhibited by using xylene as a solvent. Through this transformation, a variety of 4,5-diaryl-2H-1,2,3-triazoles were prepared in good to excellent yields and with high purities. The process is azide-free and transition-metal-free.

Two new cephalochromin derivatives, prenylcephalochromin A (1), prenylcephalochromin B (2), along with cephalochromin (3) were isolated from the Alternaria sp. ZG22 obtained from a Dasymaschalon rostratum collected from the Hainan. The structures of two new compounds were elucidated by comprehensive spectroscopic methods. Compounds 1-3 showed ��-glucosidase inhibitory activity.

Two new sesquiterpenes, litseachrandaevanes C and D (1 and 2), together with five known sesquiterpenes (3 − 7), were isolated from the stems of Fissistigma glaucescens (Hance) Merr. Their structures were elucidated using comprehensive spectroscopic methods. The inhibitory effect of all compounds on the proliferation of primary synovial cells was evaluated. Compound 3 showed inhibitory effect on the proliferation of synoviocytes, with an IC50 value of 12.5 μM.

One new norsesquiterpene polyalone A (1), and one new natural product 9-keto-cyclocolorenone (2), along with three known analogues (3–5) were isolated from the roots of Polyalthia laui. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All compounds were evaluated for their cytotoxic activities and antibacterial activities.

Three new methylated Δ

Three new methylated Δ8-pregnene steroids, stemphylisteroids A–C (1–3) were isolated from the medicinal plant Polyalthia laui-derived fungus Stemphylium sp. AZGP4-2. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. The absolute configuration of 1 was determined by X-ray crystallographic analysis. Compound 1 show antibacterial activity against Escherichia coli with the MIC value of 6.25 μg/mL, and 2 exhibited a broad spectrum of antibacterial activities against six pathogenic bacteria with the MIC values ranging from 12.5 to 50 μg/mL. The discovery of three methylated Δ8-pregnene steroids 1–3 are a further addition to diverse and complex array of methylated steroids.

Two new succinimide-containing derivatives, cladosporitins A (1) and B (2), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with a new pyrone, clapone (3), as well as the previously reported talaroconvolutin A (4) and anthraquinone (5). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HRMS spectral analysis. Compound 2 showed cytotoxicity against BEL-7042, K562 and SGC-7901 cell lines with IC50 values of 29.4 &plusmn, 0.35 &mu, M, 25.6 &plusmn, 0.47 &mu, M, and 41.7 &plusmn, 0.71 &mu, M, respectively, whereas compound 4 exhibited cytotoxicity against Hela and BEL-7042 cell lines with IC50 values of 14.9 &plusmn, 0.21 &mu, M and 26.7 &plusmn, 1.1 &mu, M, respectively. In addition, compounds 4 and 5 displayed inhibitory activity against &alpha, glycosidase, with IC50 values of 78.2 &plusmn, 2.1 &mu, M and 49.3 &plusmn, 10.6 &mu, M, respectively.

Pathogen–host interaction plays an essential role in pathogenicity. In this study, we investigated transcriptomes of one Streptococcus pneumoniae TIGR4-derived unencapsulated strain upon exposure to THP-1 human macrophage-like cells for 0.5 h, 1 h and 3 h, respectively. Expression of most genes was up-regulated and the changes of selected genes were validated by qRT-PCR. To characterize the functions of the identified genes, one locus of genes (SP1057–SP1063) was deleted in TIGR4 by insertion replacement mutagenesis. Compared to the wild-type strain, the constructed mutant exhibited lower binding and internalization activities to the THP-1 macrophages at early incubation time periods (0.5 h and/or 1 h) but not at 3 h. However, no change was observed in the intracellular survival assays. These data indicate that the SP1057–SP1063 locus is involved in the early stage of interaction with host macrophages. Further sequence and PCR analyses suggest that the SP1057–SP1063 locus was acquired by lateral transfer.

The fragmentation of 23S rRNA of 23 Haemophilus influenzae strains and eight strains belonging to other Haemophilus species was investigated. Instead of intact molecules, the 23S rRNA molecules were found to be cleaved into two to five smaller conserved fragments in most strains examined, especially in H. influenzae type b (5/6) and nontypeable strains (5/5). One or two conserved potential cleavage sites were identified by PCR analysis of the strains showing a fragmented 23S rRNA pattern. The relevant nucleotide sequences were determined and compared to H. influenzae Rd, which contains intact 23S rRNA molecules. An identical 112bp long intervening sequence (IVS) at position 542 and a conserved 121-123bp IVS sequence at position 1171 were found in two H. influenzae type b strains and one nontypeable strain. Among the strains with fragmented 23S rRNA, nearly half showed a heterogeneous cleavage pattern due to the dispersion of IVSs among different 23S rRNA operons. The localization of the conserved H. influenzae IVSs coincided well with the extensively studied IVSs among other bacteria, but differed in nucleotide sequence from any other reported IVSs. Therefore, the IVSs of Haemophilus 23S rRNA may originate from a common source that is independent of other bacteria.

The presence of a functional glpT gene in Haemophilus influenzae could be questioned, since there is only what appears to be a truncated glpT (HI0686, 143 nt in the 5'-end) available in the H. influenzae Rd genome database (Fleischmann et al. , 1995). For cloning of the glpT gene from H. influenzae type b strain Eagan, an isogenic glpT, rec-1 double mutant and a selective medium for detection of the glpT mutant strains were constructed. The recombinant plasmid carrying glpT was able to complement the isogenic glpT mutant to wild-type levels of G3P uptake and permitted growth on a selective medium with G3P as a major carbon source. The nucleotide sequences of the glpT gene were determined both directly from PCR products and from the cloned DNA insert of strain Eagan. An identical 1440 bp open reading frame with 480 deduced amino acids, highly homologous to other bacterial G3P permeases, was identified. A Northern blot analysis showed that the glpT genes in both Eagan and Rd strains were transcribed on a RNA of approximately 1.4 kb in size. Thus, it is likely that HI0686 sequence originates from a mutated glpT clone in Escherichia coli.

Few clinical studies or randomized clinical trial results have reported the impact of fast track surgery on postoperative insulin sensitivity. This study aimed to investigate the effects of fast track surgery on postoperative insulin sensitivity in patients undergoing elective open colorectal resection.Controlled, randomized clinical trial was conducted from November 2008 to January 2009 with one-month post-discharge follow-up. Seventy patients with colorectal carcinoma requiring colorectal resection were randomized into two groups: a fast track group (35 cases) and a conventional care group (35 cases). All included patients received elective open colorectal resection with combined tracheal intubation and general anesthesia. Clinical parameters (complication rates, return of gastrointestinal function and postoperative length of stay), stress index and insulin sensitivity were evaluated in both groups perioperatively.Sixty-two patients finally completed the study, 32 cases in the fast-track group and 30 cases in the conventional care group. Our findings revealed a significantly faster recovery of postoperative insulin sensitivity on postoperative day 7 in the fast-track group than that in the conventional care group. We also found a significantly shorter length of postoperative stay and a significantly faster return of gastrointestinal function in patients undergoing fast-track rehabilitation.Fast track surgery accelerates the recovery of postoperative insulin sensitivity in elective surgery for colorectal carcinoma with a shorter length of postoperative hospital stay.

To explore the effects of fast-track surgery on postoperative humoral immune function in patients undergoing elective colorectal resection.Seventy patients with colorectal carcinoma requiring colorectal resection were randomized into fast-track group (n = 35) and conventional care group (n = 35). The clinical parameters and markers of humeral immune function were evaluated in both groups postoperatively.Sixty-two patients finally completed the study, including 32 in the fast-track group and 30 in the conventional care group. There was a significantly faster recovery of postoperative humoral immunity: blood levels of globulin (24.1 ± 2.4 vs 22.1 ± 3.3 g/L, P = 0.025), immunoglobulin G (10.79 ± 2.39 vs 8.66 ± 2.09 g/L, P = 0.007) and complement 4 (0.24 ± 0.09 vs 0.17 ± 0.05 g/L, P = 0.035) at Day 3 postoperation were higher in the fast-track group than in the conventional care group. And there was also a significantly shorter length of postoperative stay (6.0 ± 1.0 vs 11.7 ± 3.8 d, P0.001) in patients undergoing fast-track rehabilitation.Fast-track surgery accelerates the recovery of postoperative humoral immune function in elective surgery for colorectal carcinoma with a shorter length of postoperative hospital stay.

To examine the effect of periconceptional multi-micronutrient supplementation on gestation and birth outcomes.A population-based community intervention program was conducted in 18 counties in China. Participants were divided into an intervention group, who received multi-micronutrient supplementation from at least 3 months before pregnancy throughout the first trimester, and a control group. Pregnant women were followed up to record information about birth outcomes. Maternal socio-economic characteristics and main birth outcomes were evaluated. Gestational age was further analyzed using survival analysis, to determine the time distribution of delivery.Periconceptional multi-micronutrient supplementation was associated with higher birth weight, birth length and occipitofrontal head circumference, and with lower incidence rates for stillbirth, low birth weight, and preterm birth. Moreover, periconceptional multi-micronutrient supplementation changed the time distribution of delivery, making the deliveries more clustered in the period between day 275 and day 295 of gestation.Our study shows that periconceptional multi-micronutrient supplementation is beneficial for fetal development and optimizes all measured aspects of health in neonates in socioeconomically disadvantaged areas in China. The change in time distribution of deliveries caused by multi-micronutrient supplementation needs further clarification.

The title chromene, C14H16O4, was isolated from the stems of Polyalthia plagioneura Diels. The molecular structure is stabilized by an intramolecular O–H...O hydrogen bond, which generates an S(6) ring. In the crystal, the molecules are linked by C—H...O interactions, generating [010] chains.

Background Highly active anti-retroviral therapy (HAART) is the current HIV/AIDS treatment modality. Despite the fact that HAART is very effective in suppressing HIV-1 replication and reducing the mortality of HIV/AIDS patients, it has become increasingly clear that HAART does not offer an ultimate cure to HIV/AIDS. The high cost of the HAART regimen has impeded its delivery to over 90% of the HIV/AIDS population in the world. This reality has urgently called for the need to develop inexpensive alternative anti-HIV/AIDS therapy. This need has further manifested by recent clinical trial failures in anti-HIV-1 vaccines and microbicides. In the current study, we characterized a panel of extracts of traditional Chinese medicinal herbal plants for their activities against HIV-1 replication. Methods Crude and fractionated extracts were prepared from various parts of nine traditional Chinese medicinal herbal plants in Hainan Island, China. These extracts were first screened for their anti-HIV activity and cytotoxicity in human CD4+ Jurkat cells. Then, a single-round pseudotyped HIV-luciferase reporter virus system (HIV-Luc) was used to identify potential anti-HIV mechanisms of these extracts. Results Two extracts, one from Euphorbiaceae, Trigonostema xyphophylloides (TXE) and one from Dipterocarpaceae, Vatica astrotricha (VAD) inhibited HIV-1 replication and syncytia formation in CD4+ Jurkat cells, and had little adverse effects on host cell proliferation and survival. TXE and VAD did not show any direct inhibitory effects on the HIV-1 RT enzymatic activity. Treatment of these two extracts during the infection significantly blocked infection of the reporter virus. However, pre-treatment of the reporter virus with the extracts and treatment of the extracts post-infection had little effects on the infectivity or gene expression of the reporter virus. Conclusion These results demonstrate that TXE and VAD inhibit HIV-1 replication likely by blocking HIV-1 interaction with target cells, i.e., the interaction between gp120 and CD4/CCR5 or gp120 and CD4/CXCR4 and point to the potential of developing these two extracts to be HIV-1 entry inhibitors.

The occurrence of generic Escherichia coli, E. coli O157, Salmonella, and Campylobacter in cattle manure, beef carcasses, catch basin water, and soils receiving manure application was determined in 21 Alberta feedlots. In cattle manure, generic E. coli (98%, 2069/2100) and Campylobacter (76%, 1590/2100) were frequently detected; E. coli O157 (7%, 143/2100) and Salmonella (1%, 20/2100) were less frequently detected. Samples from beef carcasses in the cooler following Hazard Analysis Critical Control Point interventions yielded only 1 isolate each of generic E. coli and Campylobacter (1/1653) and no Salmonella (0/1653). Catch basin water specimens were positive for generic E. coli in both the spring (62%, 13/21) and the fall (52%, 11/21). Other bacteria were detected only in the spring water specimens, including E. coli O157 (29%, 6/21), Salmonella (5%, 1/21), and Campylobacter (52%, 11/21). Generic E. coli was frequently isolated from soil specimens (30%, 27/88), but E. coli O157 was not found in soil samples obtained in the spring and was only occasionally detected in the fall samples (9%, 3/32). Salmonella were occasionally found in the soil specimens collected in the spring (3%, 2/56), but not in the fall season (0/32). Campylobacter jejuni was frequent in cattle manure (66%, 1070/1623), but rare in carcass and environmental samples. E. coli O157 and Salmonella were rarely detected in cattle or the environment. Generic E. coli and Salmonella were rarely detected on carcasses.

To screen the target genes regulated by the transcriptional repressor Syk (L) so as to explore the mechanism of Syk (L) in suppressing breast cancer.Adeno-X expression system from Clontech Company was used to construct the adenovirus-Syk. Syk negative breast cancer cells of the line MB231 were cultured and infected with adeno-Syk (L), adeno-Syk (S), and the control adeno-Lac Z respectively. cDNA microarray was used to screen the genes regulated by Syk (L) and Syk (S). Northern blotting was used to examine the cDNA microarray results.The transcriptional repressor Syk (L) was able to down-regulate the expression of the oncogenes ID1, cyclin D1, Fra1, and B-myb in the breast cancer cells. Northern blotting confirmed this regulation.Syk (L) suppresses the progression of breast cancer by down regulating the expression of the oncogenes ID1, cyclin D1, Fra1, and B-myb.

Intrauterine infection is an important cause of some birth defects worldwide. The most common pathogens include rubella virus, cytomegaloviurs, ureaplasma urealyticum, toxoplasma, etc. General information about these pathogens in epidemiology, consequence of birth defects, and the possible mechanisms in the progress of birth defects, and the interventions to prevent or treat these pathogens' infections are described. The infections caused by rubella virus, cytomegaloviurs, ureaplasma urealyticum, toxoplasma, etc. are common, yet they are proved to be fatal during the pregnant period, especially during the first trimester. These infections may cause sterility, abortion, stillbirth, low birth weight, and affect multiple organs that may induce loss of hearing and vision, even fetal deformity and the long-term effects. These pathogens' infections may influence the microenvironment of placenta, including levels of enzymes and cytokines, and affect chondriosome that may induce the progress of birth defect. Early diagnosis of infections during pregnancy should be strengthened. There are still many things to be settled, such as the molecular mechanisms of birth defects, the effective vaccines to certain pathogens. Birth defect researches in terms of etiology and the development of applicable and sensitive pathogen detection technology and methods are imperative.

TheglpTQoperon ofHaemophilus influenzaetype b (Hib) and nontypeableH. influenzae(NTHi) strains is highly conserved, except for a 1.4-kbglpTQintergenic region that was found in most Hib strains. The presence of this intergenic region results in divergentglpTQtranscriptional profiles for Hib and NTHi where Hib strains appear to have evolved an alternative promoter forglpQexpression. Based on the intergenic region's low G+C content, we speculate that this DNA fragment was acquired by lateral transfer.

Themiggene ofStreptococcus dysgalactiae, a major bovine mastitis pathogen, encodes two plasma protein-binding receptors, α2-macroglobulin (α2-M) and immunoglobulin G (IgG). In this study, themiggene from oneS. dysgalactiaeisolate was cloned and expressed inEscherichia coli. The IgG receptor region encoded bymigwas conserved in 16S. dysgalactiaestrains. An isogenicmigmutant was constructed by allele replacement mutagenesis of the wild-type gene inS. dysgalactiae. The IgG-binding activity was lost in themigmutant strain, whereas the α2-M receptor activity was still expressed but was detected only in the culture supernatant. In flow cytometry phagocytosis and bacterial-colony-counting bactericidal assays, the wild-type strain was found to be significantly more resistant to phagocytosis and killing by bovine neutrophils (PMNs) than themigmutant strain when bacteria were preincubated with bovine serum. We therefore speculate that the Mig protein ofS. dysgalactiaeplays a role in virulence of the bacteria by binding to the plasma protein α2-M or IgG and thus preventing phagocytosis by bovine PMNs.

The molecular conservation of a surface-exposed lipoprotein, protein D, of Haemophilus influenzae was studied by cloning and sequencing of the gene encoding protein D from three encapsulated type b strains and three nontypeable strains of H. influenzae. These nucleotide sequences were analyzed with previously reported sequences from one type b strain and one nontypeable strain. The nucleotide sequences and the deduced amino acid sequences for protein D were highly conserved. The deduced amino acid sequence (364 amino acids) of protein D from six strains differed only in two amino acids near the C-terminal end. The remaining two strains, one type b and one nontypeable, differed from the consensus sequence in 7 amino acids each. Protein D is 64 and 36% identical and 77 and 56% similar to the glycerophosphodiester phosphodiesterases (GlpQ) of Escherichia coli and Bacillus subtilis.

Bioassay-guided isolation studies of the extract of Canthium horridum Bl. stem led to the isolation of ten compounds: (+)-syringaresinol (1), scoparone (2), scopoletin (3), 3′-methoxy-4′-hydroxy- trans-cinnamaldehyde (4), sinapic aldehyde (5), syringic acid (6), mannitol (7), vanillic acid 4- O-β-D-glucopyranoside (8), β-daucosterol (9), and β-sitosterol (10). Compounds 1-10 were reported for the first time from this species, and compounds 1, 4, 5, 6, and 8 from the genus. The antimicrobial activities of the isolated compounds were studied; 6 had the highest activity against Bacillus subtilis, but 1 showed good activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Compounds 2, 4 and 6 also inhibited the growth of these three bacteria. None of the compounds demonstrated inhibitory activity against Aspergillus niger.

In the title compound, C14H10O4·H2O, isolated from the roots of Calophyllum membranaceum, the xanthene ring system is almost planar (r.m.s. deviation = 0.008 Å). In the crystal structure, intermolecular O—H...O and O—H...(O,O) hydrogen bonds connect the molecules.

Background Streptococcus pneumoniae infection starts from colonization of the host respiratory tract where interaction with host respiratory tract epithelial cells occurs. To investigate pneumococcal genes that are involved in the early stage of interaction with host epithelial cells, transcriptional responses of an encapsulated pathogenic pneumococcal strain TIGR4 upon exposure to human lung epithelial cells A549 for 0.5 h and 1 h time periods were investigated by using TIGR (JCVI) microarray technology. Gene expression changes were validated by quantitative real-time PCR (qRT-PCR) analysis. Findings We observed different transcriptional profiles at two incubation time periods in which most gene expressions were down-regulated at 0.5 h but up-regulated at 1 h. Many genes associated with ribonucleotide biosynthesis were down-regulated at both time points, whereas the genes associated with cell envelope, energy metabolism, transport and protein synthesis were mostly up-regulated at 1 h. Furthermore, these profiles were compared to the transcriptomes of a TIGR4-derived strain in response to human macrophages for the same time periods. We found one set of genes that exhibited similar expression changes upon exposure to both types of host cells, including cell envelope-associated bgaA (SP0648) and nanA (SP1693), and uncharacterized gene clusters such as SP1677–SP1680 and SP1688–SP1690. Conclusion These data indicate that at the early stage of interaction with host epithelial cells, a complex gene regulation and expression change occur in bacteria. Some of them might play an essential role during pathogen-host interactions and for the establishment of infection.

In eubacteria Escherichia coli and Bacillus subtilis, the glpTQ operon is involved in utilization of glycerol3phosphate (G3P) as a carbon source, and the glpT and glpQ genes transcribe as a single unit. In Haemophilus influenzae, we have previously characterized the glpT and glpQ homologues encoding glycerol-3-phosphate permease and glycerophosphodiester phosphodiesterase, respectively. The protein encoded by glpQ is also called Protein D and is involved in pathogenesis. In this study, we analysed the glpTQ transcripts in one H. injluenzae type b (Hib) and one nontypeable (NTHi) strain, and characterized potential function of the 1.4 kb glpTQ intergenic region that exists in most Hib strains but not in NTHi strains. In Northern blot and RT-PCR analysis, the glpT and glpQ genes in the Hib strain transcribed separately, whereas a co-transcribed glpTQ was found in the NTHi strain. It suggests that the 1.4 kb glpTQ intergenic region in Hib strains partially blocks the glpTQ operon transcription. When an isogenic mutant strain where the 1.4 kb region was replaced with a kanamycin cassette in the chromosome of the wildtype strain was tested, the blockage of the glpTQ transcription disappeared. We therefore conclude that due to the existence of the 1.4 kb glpTQ intergenic region in Hib strains, the glpTQ operons between Hib and NTHi strains transcribed differently. Based on a much lower G+C content (26 %) of the 1.4 kb DNA coding region than an overall G+C content of 38 % for the H. influenzae genome, we speculate that the 1.4 kb region might have been acquired by lateral transfer from an organism with a lower G+C content.