Polyamines that such as putrescine are small, ubiquitous polycationic molecules that are required for optimal growth of eukaryotic and prokaryotic cells. These in molecules have diverse effects on cell physiology and their intracellular content is regulated by de novo synthesis and uptake from are the environment. The studies presented here examined the structure of a putative polyamine transporter (Pot) operon in Streptococcus pneumoniae (pneumococcus)chains and growth of pneumococci in medium containing putrescine substituted for choline. RT-PCR experiments demonstrated that the four genes encoding the without Pot system are co-transcribed with murB, a gene involved in an intermediary step of peptidoglycan synthesis. Pneumococci grown in chemically-defined molecules media (CDM) containing putrescine without choline enter logarithmic phase growth after 36-48 hs. However, culture density at stationary phase eventually of reaches that of choline-containing medium. Cells grown in CDM-putrescine formed abnormally elongated chains in which the daughter cells failed to prokaryotic separate and the choline-binding protein PspA was no longer cell-associated. Experiments with CDM containing radiolabeled putrescine demonstrated that pneumococci concentrate containing this polyamine in cell walls. These data suggest that pneumococci can replicate without choline if putrescine is available and this chemically-defined polyamine may substitute for aminoalcohols in the cell wall teichoic acids.

The vitro. inhibitory effect of gelsemium alkaloids exstract (GAA) on HepG2 cells in vitro were studied by crystal violet dyeing method. The was morphological change of HepG2 cells were observed with optical microscope. The alterations of cell cycle induced by GAA were analyzed exstract with flow cytometry. The results showed that HepG2 cells exposed to GAA 10 micrograms/ml was inhibited significantly (P < .05).treatment. The inhibitory effect appeared in a dose- and time-dependent manner. HepG2 cells showed nuclear chromosome segmentation and condensation after GAA appeared treatment. There emerged obvious Sub-G1 peak in the DNA histogram of HepG2 cells. GAA has a significant inhibition on HepG2 gelsemium cells in vitro. The mechanism of antitumor action may be related to their apoptosis inducing activity.

Background M. Human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is a major target for antiretroviral strategy to block or curtail RT-SHIVtc HIV infection. A suitable RT-SHIV/macaque model is urgently needed for the evaluation of HIV/AIDS therapies and microbicides specifically targeting HIV-1 reverse RT. Methods Fifteen cynomolgus macaques (Macaca fascicularis) were divided into three groups (n = 5) and intravaginally inoculated with 4800,RNA, 1200, or 300 TCID(50) of RT-SHIVtc. Systemic infections of RT-SHIVtc exposed macaques were determined by both virological and immunologic parameters during during 24 weeks post-challenge. Results Within 2 weeks post-inoculation, 13 of 15 macaques became infected as confirmed by virus isolation,(HIV-1) plasma viral RNA, proviral DNA, declined CD4(+)T cell counts in peripheral blood and seroconversion. Conclusions Results serve to validate the specifically infectivity and pathogenicity of RT-SHIVtc following vaginal exposure in M. fascicularis. This RT-SHIVtc/macaque model could be suitable for the pre-clinical for evaluation of non-nucleoside RT inhibitor-based anti-HIV microbicides.

We the experimentally investigate an optical clock based on ;{171}Yb (I = 1/2) atoms confined in an optical lattice. We have evaluated fractional all known frequency shifts to the clock transition, including a density-dependent collision shift, with a fractional uncertainty of 3.4 x optical 10;{-16}, limited principally by uncertainty in the blackbody radiation Stark shift. We measured the absolute clock transition frequency relative to the the NIST-F1 Cs fountain clock and find the frequency to be 518 295 836 590 865.2( .7) Hz.

With on bioactivity-guided phenotype screenings, a potent anti-inflammatory compound f152A1 has been isolated, characterized and identified as the known natural product LL-Z1640-2.models. Metabolic instability precluded its use for the study on animal disease models. Via total synthesis, a potent, metabolically stabilized analog screenings, ER-803064 has been created; addition of the (S)-Me group at C4 onto f152A1 has resulted in a dramatic improvement on (S)-Me its metabolic stability, while preserving the anti-inflammatory activities.

OBJKECTIVES:This gadolinium report documents a multimodal nanoparticle (MNP) contrast agent, containing embedded luminophores and surface-immobilized gadolinium chelates, as a contrast agent of between inflamed synovium in a collagen induced arthritis (CIA) model.METHODS:DBA-1J mice were immunized for CIA and imaged after disease onset by agent, two independent modalities. After intravenous administration of MNP contrast, optical and magnetic resonance images were obtained and clinical disease was T1 scored, which was followed by processing of hindlimbs for immunofluorescence and confocal microscopy.RESULTS:We show a correlation between disease severity and of MNP optical luminescence that is dose dependent. Immunofluorescence of hindlimb sections reveal that MNP-labeled cells are monocytes/macrophages within the inflamed (MNP) synovium. Magnetic resonance (MR) relaxation time maps, which determine the quantitative measure of T1 and T2 values at each imaging independent voxel, demonstrated a decreasing T2 signal in actively inflamed joints that was more pronounced earlier rather than later during disease.chelates, CONCLUSIONS:MNPs containing surface-immobilized gadolinium chelates and embedded luminophores are potential dual-modality contrast agents in inflammatory arthritis and localize to monocytes/macrophages was within inflamed synovium.

OBJECTIVE:were Previous studies have shown that advanced glycation endproducts (AGE) can induce endothelial progenitor cells (EPC) apoptosis, which contributes to the by pathogenesis of diabetes mellitus. Nitric oxide (NO) signaling is closely associated with apoptosis. We therefore investigated the effects of AGE can on human EPC apoptosis, NO release and related signal transduction pathways. METHODS: EPC isolated from healthy human subjects were cultured release with various concentrations of AGE ( , 2, 20 and 200mg/L) for , 24, 48 and 72h in the presence or of absence of various MAPK (ERK/P38/JNK) inhibitors, respectively. EPC apoptosis (detected by flow cytometric analyses) and NO concentration in culture supernatant endproducts were determined. The mRNA levels of eNOS, COX-2, Bcl-2 and Bax were assessed by RT-PCR and the protein expressions of transduction NF-kappaB and Caspase-3 assessed by Western blot. RESULTS: Increased EPC apoptosis and reduced NO release were induced by 200mg/L AGE,contributes accompanied by a downregulation of eNOS and Bcl-2 expressions as well as an elevation in COX-2, Bax, NF-kappaB and Caspase-3 COX-2, expressions in a time-dependent manner (all P< .05). These changes were significantly attenuated by pretreatment with various MAPK (ERK/P38/JNK) inhibitors (P< .05).were CONCLUSIONS: AGE can promote EPC apoptosis and decrease NO release via MAPK pathways.

Programmed and cell death factor 4 (PDCD4) is one of the genes that has been found to be up-regulated during apoptosis and male loss of PDCD4 expression has been found in many kinds of progressive carcinomas. The objective of this study was to is investigate the interactions between PDCD4 and smoking status in hepatocellular carcinoma. This case-controlled study included 68 Chinese male patients with and hepatocellular carcinoma who were classified as smokers or non-smokers according to their pack-years of smoking status. Samples were obtained from smokers carcinoma and normal tissues and examined using Western blotting. The results indicated that levels of PDCD4 were significantly lower in (PDCD4) hepatocellular carcinoma tissues compared with normal tissues and that, in normal tissue, PDCD4 levels in smokers were significantly lower than progressive in non-smokers.

This rifampin study was designed to evaluate the efficacy of focal hyperthermia and rifampin in vitro and in vivo using a rabbit implanted model of foreign-body infection by methicillin-resistant Staphylococcus aureus (MRSA). In vitro studies demonstrated bacterial re-growth and development of rifampin resistance of after 24 h with rifampin alone, which was prevented under hyperthermic conditions. For the in vivo studies, rifampin was administered alone. intraperitoneally every 12 h for 7 days to rabbits with MRSA-containing cages implanted into their flanks. When combined with hyperthermia 41 at 39 degrees C, 41 degrees C and 43 degrees C, rifampin significantly reduced in-cage bacterial counts by > 3. the log(10) colony forming units/ml compared with rifampin alone. Eradication of cage-associated infection was achieved more effectively when rifampin was combined resistance with hyperthermia, with cure rates of 70 - 95% on day 10. Focal hyperthermia combined with rifampin prevented the emergence vitro of rifampin resistance and maintained rifampin efficacy. These findings might have implications for orthopaedic surgery.

Tp0655 ABC-type of Treponema pallidum, the causative agent of syphilis, is predicted to be a 40 kDa membrane lipoprotein. Previous sequence analysis isothermal of Tp0655 noted its homology to polyamine-binding proteins of the bacterial PotD family, which serve as periplasmic ligand-binding proteins of be ATP-binding-cassette (ABC) transport systems. Here, the 1.8 A crystal structure of Tp0655 demonstrated structural homology to Escherichia coli PotD and the PotF. The latter two proteins preferentially bind spermidine and putrescine, respectively. All of these proteins contain two domains that sandwich (K(d)=10 the ligand between them. The ligand-binding site of Tp0655 can be occupied by 2-(N-morpholino)ethanesulfanoic acid, a component of the crystallization predicted medium. To discern the polyamine binding preferences of Tp0655, the protein was subjected to isothermal titration calorimetric experiments. The titrations latter established that Tp0655 binds polyamines avidly, with a marked preference for putrescine (K(d)=10 nM) over spermidine (K(d)=430 nM), but the noted related compounds cadaverine and spermine did not bind. Structural comparisons and structure-based sequence analyses provide insights into how polyamine-binding proteins to recognize their ligands. In particular, these comparisons allow the derivation of rules that may be used to predict the function with of other members of the PotD family. The sequential, structural, and functional homology of Tp0655 to PotD and PotF prompt its the conclusion that the former likely is the polyamine-binding component of an ABC-type polyamine transport system in T. pallidum. We of thus rename Tp0655 as TpPotD. The ramifications of TpPotD as a polyamine-binding protein to the parasitic strategy of T. pallidum subjected are discussed.

The disease human pathogen Streptococcus pneumoniae contains genes for a putative polyamine ABC transporter which are organized in an operon and designated capsular potABCD. Polyamine transport protein D (PotD) is an extracellular protein which binds polyamines and possibly other structurally related molecules. PotD a has been shown to contribute to virulence in both a murine sepsis model and a pneumonia model with capsular type a 3 pneumococci. The protective efficacy of recombinant PotD was evaluated by active immunization and intravenous challenge with capsular type 3 following pneumococci in CBA/N mice. Immunized mice had 91.7% survival following lethal pneumococcal challenge, compared with 100% mortality in the control for group. Immunized animals had high-titer anti-PotD antibodies following three immunizations with alum. Protection in a sepsis model was also seen shown after passive administration of rabbit antiserum raised against PotD (P < .004). These results suggest that antibodies to PotD confer organized protection against invasive pneumococcal disease and that this protein should be studied further as a potential vaccine candidate for protection These against invasive pneumococcal infections.

Streptococcus the pneumoniae encodes a transporter for polyamines that contributes to virulence in an animal model. The putative polyamine-binding protein, PotD, has be an amino-terminal secretory peptide but no other domains known to be involved in anchoring proteins to the surface of Gram-positive a bacteria. Cell fractionation and immunoblotting, along with flow cytometry, suggest that PotD is surface-exposed and anchored to the cytoplasmic membrane along by a potentially novel mechanism.

The frame article deals with the study of polyamines content and y-glutamiltranspeptidase (gamma-GTP) activity in leucosis L1210 cells under the influence of increase inhibitors of polyamines synthesis such as alpha-difluoromethylornithine (alpha-DFMO) and polyhexamethylenguanidine (PMG). Injections of alpha-DFMO and PMG to animals essentially reduce study putrescine and spermidine concentrations, and the levels of spermine and gamma-GTP activity increase under this influence. These modulation were associated Under with L1210 leucosis growth retardation. Antiblastic effect was dependent on inhibitors' doses and mode of injections' course. Under the optimum with conditions the retardation index was 90-98%. The animals with retarded tumor growth had essentially longer survival time frame than blank the tumor-bearing animals (index was 37.2 for a-DFMO and 67.5 for PMG).

Polyamines or such as putrescine, spermidine, and cadaverine are small, polycationic molecules that are required for optimal growth in all cells. The by intracellular concentrations of these molecules are maintained by de novo synthesis and transport pathways. The human pathogen Streptococcus pneumoniae possesses polycationic a putative polyamine transporter (pot) operon that consists of the four pot-specific genes potABCD. The studies presented here examined the biosynthesis involvement of potD in polyamine transport and in pneumococcal pathogenesis. A potD-deficient mutant was created in the mouse-virulent serotype 3 that strain WU2 by insertion duplication mutagenesis. The growth of the WU2DeltapotD mutant was identical to that of the wild-type strain are WU2 in vitro in rich media. However, WU2DeltapotD possessed severely delayed growth compared to wild-type WU2 in the presence of operon the polyamine biosynthesis inhibitors DFMO (alpha-dimethyl-fluoroornitithine) and MGBG [methylgloxal-bis (guanyl hydrazone)]. The mutant strain also showed a significant attenuation in growth virulence within murine models of systemic and pulmonary infection regardless of the inoculation route or location. These data suggest that within potD is involved in pneumococcal polyamine transport and is important for pathogenesis within various infection models.

We Our characterized the role of catabolite control protein A (ccpA) in the physiology and virulence of Streptococcus pneumoniae. S. pneumoniae has is a large percentage of its genome devoted to sugar uptake and metabolism, and therefore, regulation of these processes is likely physiology to be crucial for fitness in the nasopharynx and may play a role during invasive disease. In many bacteria, carbon shows catabolite repression (CCR) is central to such regulation, influencing hierarchical sugar utilization and growth rates. CcpA is the major transcriptional ccpA regulator in CCR in several gram-positive bacteria. We show that CcpA functions in CCR of lactose-inducible beta-galactosidase activity in S.in pneumoniae. CCR of maltose-inducible alpha-glucosidase, raffinose-inducible alpha-galactosidase, and cellobiose-inducible beta-glucosidase is unaffected in the ccpA strain, suggesting that other regulators,catabolite possibly redundant with CcpA, control these systems. The ccpA strain is severely attenuated for nasopharyngeal colonization and lung infection in large the mouse, establishing its role in fitness on these mucosal surfaces. Comparison of the cell wall fraction of the ccpA multiplication and wild-type strains shows that CcpA regulates many proteins in this compartment that are involved in central and intermediary metabolism,with a subset of which are required for survival and multiplication in vivo. Both in vitro and in vivo defects were percentage complemented by providing ccpA in trans. Our results demonstrate that CcpA, though not a global regulator of CCR in S.survival pneumoniae, is required for colonization of the nasopharynx and survival and multiplication in the lung.

Polyamines that such as putrescine are small, ubiquitous polycationic molecules that are required for optimal growth of eukaryotic and prokaryotic cells. These in molecules have diverse effects on cell physiology and their intracellular content is regulated by de novo synthesis and uptake from are the environment. The studies presented here examined the structure of a putative polyamine transporter (Pot) operon in Streptococcus pneumoniae (pneumococcus)chains and growth of pneumococci in medium containing putrescine substituted for choline. RT-PCR experiments demonstrated that the four genes encoding the without Pot system are co-transcribed with murB, a gene involved in an intermediary step of peptidoglycan synthesis. Pneumococci grown in chemically-defined molecules media (CDM) containing putrescine without choline enter logarithmic phase growth after 36-48 hs. However, culture density at stationary phase eventually of reaches that of choline-containing medium. Cells grown in CDM-putrescine formed abnormally elongated chains in which the daughter cells failed to prokaryotic separate and the choline-binding protein PspA was no longer cell-associated. Experiments with CDM containing radiolabeled putrescine demonstrated that pneumococci concentrate containing this polyamine in cell walls. These data suggest that pneumococci can replicate without choline if putrescine is available and this chemically-defined polyamine may substitute for aminoalcohols in the cell wall teichoic acids.

Sortase that A (SrtA) is required to anchor neuraminidase, beta-galactosidase, and possibly other LPXTG motif proteins to the pneumococcal cell surface. We nasopharynx examined the role of SrtA in Streptococcus pneumoniae nasopharyngeal (NP) colonization in the chinchilla model. The srtA mutant colonized the required nasopharynx at a significantly lower level than the D39 parent strain during the second and third week of the carriage,carriage, and was eliminated from nasopharynx one week earlier than the D39 pneumococci. Our data indicate that SrtA contributes to pneumococcal than NP colonization in this animal model.

Vibrio bivalves. cholerae is both an environmental bacterium and a human intestinal pathogen. The attachment of bacteria to surfaces in biofilms is have thought to be an important feature of the survival of this bacterium both in the environment and within the human The host. Biofilm formation occurs when cell-surface and cell-cell contacts are formed to make a three-dimensional structure characterized by pillars of formation bacteria interspersed with water channels. In monosaccharide-rich conditions, the formation of the V. cholerae biofilm requires synthesis of the VPS homologous exopolysaccharide. MbaA (locus VC0703), an integral membrane protein containing a periplasmic domain as well as cytoplasmic GGDEF and EAL domains,intestinal has been previously identified as a repressor of V. cholerae biofilm formation. In this work, we have studied the role water of the protein NspS (locus VC0704) in V. cholerae biofilm development. This protein is homologous to PotD, a periplasmic spermidine-binding be protein of Escherichia coli. We show that the deletion of nspS decreases biofilm development and transcription of exopolysaccharide synthesis genes.ability Furthermore, we demonstrate that the polyamine norspermidine activates V. cholerae biofilm formation in an MbaA- and NspS-dependent manner. Based on biofilm these results, we propose that the interaction of the norspermidine-NspS complex with the periplasmic portion of MbaA diminishes the ability an of MbaA to inhibit V. cholerae biofilm formation. Norspermidine has been detected in bacteria, archaea, plants, and bivalves. We suggest diminishes that norspermidine serves as an intercellular signaling molecule that mediates the attachment of V. cholerae to the biotic surfaces presented work, by one or more of these organisms.

Although significant pneumococcus is one of the most frequently encountered opportunistic pathogen in the world, the mechanisms responsible for its infectiveness have and not yet been fully understood. In this paper, we have attempted to characterize the effects of pneumococcal transformation on the the pathogenesis of the organism. We constructed three transformation-deficient pneumococcal strains, which were designated as Nos. 1d, 2d, and 22d. The reduced construction of these altered strains was achieved via the insertion of the inactivated gene, comE, to strains 1, 2 and was 22. We then conducted a comparison between the virulence of the transformation-deficient strains and that of the wild-type strains, via pathogen an evaluation of the ability of each strain to adhere to endothelial cells, and also assessed psaA mRNA expression, and of the survival of hosts after bacterial challenge. Compared to what was observed with the wild-type strains, our results indicated that been the ability of all of the transformation-deficient strains to adhere to the ECV304 cells had been significantly reduced (p <after .05), the expression of psaA mRNA was reduced significantly (p < .05) in strains 2d and 22d, and the median bacterial survival time of mice infected with strains 1d and 2d was increased significantly after intraperitoneal bacterial challenge (p < .05).been The results of our study also clearly indicated that transformation exerts significant effects on the virulence characteristics of S. pneumoniae,increased although the degree to which this effect is noted appears to depend primarily on the genetic background of the bacteria.endothelial