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Sample records for anti-hiv antibodies b12

  1. Anti-HIV Antibody Responses and the HIV Reservoir Size during Antiretroviral Therapy

    PubMed Central

    Lee, Sulggi A.; Bacchetti, Peter; Chomont, Nicolas; Fromentin, Remi; Lewin, Sharon R.; O’Doherty, Una; Palmer, Sarah; Richman, Douglas D.; Siliciano, Janet D.; Yukl, Steven A.; Deeks, Steven G.; Burbelo, Peter D.

    2016-01-01

    Background A major challenge to HIV eradication strategies is the lack of an accurate measurement of the total burden of replication-competent HIV (the “reservoir”). We assessed the association of anti-HIV antibody responses and the estimated size of the reservoir during antiretroviral therapy (ART). Methods We evaluated anti-HIV antibody profiles using luciferase immunoprecipitation systems (LIPS) assay in relation to several blood-based HIV reservoir measures: total and 2-LTR DNA (rtPCR or droplet digital PCR); integrated DNA (Alu PCR); unspliced RNA (rtPCR), multiply-spliced RNA (TILDA), residual plasma HIV RNA (single copy PCR), and replication-competent virus (outgrowth assay). We also assessed total HIV DNA and RNA in gut-associated lymphoid tissue (rtPCR). Spearman correlations and linear regressions were performed using log-transformed blood- or tissue-based reservoir measurements as predictors and log-transformed antibody levels as outcome variables. Results Among 51 chronically HIV-infected ART-suppressed participants (median age = 57, nadir CD4+ count = 196 cells/mm3, ART duration = 9 years), the most statistically significant associations were between antibody responses to integrase and HIV RNA in gut-associated lymphoid tissue (1.17 fold-increase per two-fold RNA increase, P = 0.004) and between antibody responses to matrix and integrated HIV DNA in resting CD4+ T cells (0.35 fold-decrease per two-fold DNA increase, P = 0.003). However, these associations were not statistically significant after a stringent Bonferroni-adjustment of P<0.00045. Multivariate models including age and duration of ART did not markedly alter results. Conclusions Our findings suggest that anti-HIV antibody responses may reflect the size of the HIV reservoir during chronic treated HIV disease, possibly via antigen recognition in reservoir sites. Larger, prospective studies are needed to validate the utility of antibody levels as a measure of the total body burden of HIV

  2. A SINGLE INJECTION OF ANTI-HIV-1 ANTIBODIES PROTECTS AGAINST REPEATED SHIV CHALLENGES

    PubMed Central

    Pegu, Amarendra; Nason, Martha C.; Klein, Florian; Gazumyan, Anna; Golijanin, Jovana; Buckler-White, Alicia; Sadjadpour, Reza; Wang, Keyun; Mankoff, Zachary; Schmidt, Stephen D.; Lifson, Jeffrey D.; Mascola, John R.; Nussenzweig, Michel C.; Martin, Malcolm A.

    2016-01-01

    Despite the success of potent anti-retroviral drugs in controlling HIV-1 infection, little progress has been made in generating an effective HIV-1 vaccine. Although passive transfer of anti-HIV-1 bNAbs can protect mice or macaques against a single high dose challenge with HIV or SIV/HIV chimeric viruses respectively1-8, the long-term efficacy of a passive antibody transfer approach for HIV-1 has not been examined. Based on the relatively long term protection conferred by Hepatitis A immune globulin, we tested the efficacy of a single injection (20mg/kg) of four anti-HIV-1 neutralizing monoclonal antibodies (MAbs) (VRC01, VRC01-LS, 3BNC117, and 10-10749-12) in blocking repeated weekly low dose virus challenges of the clade B SHIVAD8. Compared to control animals, which required 2 to 6 challenges (median=3 weeks) for infection, a single bNAb infusion prevented virus acquisition for up to 23 weeks. This effect depended on antibody potency and half-life. The highest levels of plasma neutralizing activity and correspondingly, the longest protection, were found in monkeys administered the more potent antibodies, 3BNC117 and 10-1074 (median=13 and 12.5 weeks respectively). VRC01, which showed lower plasma-neutralizing activity, protected for a shorter time (median=8 weeks). The introduction of a mutation that extends antibody half-life into the Fc domain of VRC01 increased median protection from 8 to 14.5 weeks. If administered in to populations at high risk for HIV-1 transmission, such an immunoprophylaxis regimen could have a major impact on virus transmission. PMID:27120156

  3. Transgenic Production of an Anti HIV Antibody in the Barley Endosperm

    PubMed Central

    Hensel, Goetz; Floss, Doreen M.; Arcalis, Elsa; Sack, Markus; Melnik, Stanislav; Altmann, Friedrich; Rutten, Twan; Kumlehn, Jochen; Stoger, Eva; Conrad, Udo

    2015-01-01

    Barley is an attractive vehicle for producing recombinant protein, since it is a readily transformable diploid crop species in which doubled haploids can be routinely generated. High amounts of protein are naturally accumulated in the grain, but optimal endosperm-specific promoters have yet to be perfected. Here, the oat GLOBULIN1 promoter was combined with the legumin B4 (LeB4) signal peptide and the endoplasmic reticulum (ER) retention signal (SE)KDEL. Transgenic barley grain accumulated up to 1.2 g/kg dry weight of recombinant protein (GFP), deposited in small roundish compartments assumed to be ER-derived protein bodies. The molecular farming potential of the system was tested by generating doubled haploid transgenic lines engineered to synthesize the anti-HIV-1 monoclonal antibody 2G12 with up to 160 μg recombinant protein per g grain. The recombinant protein was deposited at the periphery of protein bodies in the form of a mixture of various N-glycans (notably those lacking terminal N-acetylglucosamine residues), consistent with their vacuolar localization. Inspection of protein-A purified antibodies using surface plasmon resonance spectroscopy showed that their equilibrium and kinetic rate constants were comparable to those associated with recombinant 2G12 synthesized in Chinese hamster ovary cells. PMID:26461955

  4. High titer anti-HIV antibody reactivity associated with a paraprotein spike in a homosexual male with AIDS related complex.

    PubMed

    Ng, V L; Hwang, K M; Reyes, G R; Kaplan, L D; Khayam-Bashi, H; Hadley, W K; McGrath, M S

    1988-05-01

    We observed a human immunodeficiency virus (HIV)-infected homosexual male with AIDS related complex (ARC) who had a serum globulin level of 80 g/L. Serum protein electrophoresis revealed a gamma globulin fraction of 40 g/L, of which 50% (20 g/L) was contained within a paraprotein spike, comprised predominantly of IgG kappa. This patient also had high titer anti-HIV antibodies in his serum, which were Western blot reactive at a final dilution of 1:500,000, and recognized gp120env, p66pol, p55gag, p53pol, p41gag, and p24gag. Because paraproteins in the past have been shown to be directed against specific antigens, we purified this patient's paraprotein using a modified high performance liquid chromatography (HPLC)-hydroxylapatite procedure and tested the purified paraprotein for anti-HIV antibody activity. The purified paraprotein retained anti-HIV antibody activity to a final dilution of 1:100,000, and recognized p66pol, p55gag, p53pol, p41gag, and p24gag. The recognition of both "gag" and "pol" gene products suggested that the purified paraprotein might not be monoclonal in origin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that the purified paraprotein contained at least two immunoglobulin light chain species (Mol wt 30 to 33 Kd). Affinity chromatography of the purified paraprotein using a p24-Sepharose 4B matrix separated the "gag" and "pol" antibody activities. Immunoglobulin gene rearrangement analysis of a bone marrow aspirate (which contained 15% plasma cells) failed to reveal a clonal population of immunoglobulin producing cells. We conclude that this patient's paraprotein accounted for most of the anti-HIV activity present in whole serum, and that this paraprotein was not monoclonal in origin.

  5. Functional advantage of educated KIR2DL1(+) natural killer cells for anti-HIV-1 antibody-dependent activation.

    PubMed

    Gooneratne, S L; Center, R J; Kent, S J; Parsons, M S

    2016-04-01

    Evidence from the RV144 HIV-1 vaccine trial implicates anti-HIV-1 antibody-dependent cellular cytotoxicity (ADCC) in vaccine-conferred protection from infection. Among effector cells that mediate ADCC are natural killer (NK) cells. The ability of NK cells to be activated in an antibody-dependent manner is reliant upon several factors. In general, NK cell-mediated antibody-dependent activation is most robust in terminally differentiated CD57(+) NK cells, as well as NK cells educated through ontological interactions between inhibitory killer immunoglobulin-like receptors (KIR) and their major histocompatibility complex class I [MHC-I or human leucocyte antigen (HLA-I)] ligands. With regard to anti-HIV-1 antibody-dependent NK cell activation, previous research has demonstrated that the epidemiologically relevant KIR3DL1/HLA-Bw4 receptor/ligand combination confers enhanced activation potential. In the present study we assessed the ability of the KIR2DL1/HLA-C2 receptor/ligand combination to confer enhanced activation upon direct stimulation with HLA-I-devoid target cells or antibody-dependent stimulation with HIV-1 gp140-pulsed CEM.NKr-CCR5 target cells in the presence of an anti-HIV-1 antibody source. Among donors carrying the HLA-C2 ligand for KIR2DL1, higher interferon (IFN)-γ production was observed within KIR2DL1(+) NK cells than in KIR2DL1(-) NK cells upon both direct and antibody-dependent stimulation. No differences in KIR2DL1(+) and KIR2DL1(-) NK cell activation were observed in HLA-C1 homozygous donors. Additionally, higher activation in KIR2DL1(+) than KIR2DL1(-) NK cells from HLA-C2 carrying donors was observed within less differentiated CD57(-) NK cells, demonstrating that the observed differences were due to education and not an overabundance of KIR2DL1(+) NK cells within differentiated CD57(+) NK cells. These observations are relevant for understanding the regulation of anti-HIV-1 antibody-dependent NK cell responses.

  6. Stimulation of the primary anti-HIV antibody response by IFN-{alpha} in patients with acute HIV-1 infection

    PubMed Central

    Adalid-Peralta, Laura; Godot, Véronique; Colin, Céline; Krzysiek, Roman; Tran, Thi; Poignard, Pascal; Venet, Alain; Hosmalin, Anne; Lebon, Pierre; Rouzioux, Christine; Chêne, Geneviève; Emilie, Dominique

    2008-01-01

    Type I IFNs are needed for the production of antiviral antibodies in mice; whether they also stimulate primary antibody responses in vivo during human viral infections is unknown. This was assessed in patients acutely infected with HIV-1 and treated with IFN-α2b. Patients with acute HIV-1 infection were randomized to receive anti-retroviral therapy alone (Group A, n=60) or combined for 14 weeks with pegylated-IFN-α2b (Group B, n=30). Emergence of anti-HIV antibodies was monitored during 32 weeks by Western blot (WB) analyses of serum samples. IFN-α2b treatment stimulated the production of anti-HIV antibodies. On Week 32, 19 weeks after the last IFN-α2b administration, there were 8.5 (6.5–10.0) HIV WB bands (median, interquartile range) in Group B and 7.0 (5.0–10.0) bands in Group A (P=0.054), and band intensities were stronger in Group B (P<0.05 for p18, p24, p34, p40, and p55 HIV antigens). IFN-α2b treatment also increased circulating concentrations of the B cell-activating factor of the TNF family (P<0.001) and ex vivo production of IL-12 (P<0.05), reflecting its effect on innate immune cells. Withdrawal of antiretroviral treatment on Week 36 resulted in a lower rebound of HIV replication in Group B than in Group A (P<0.05). Therefore, type I IFNs stimulate the emerging anti-HIV immune response in patients with acute HIV-1 infection, resulting in an improved control of HIV replication. Type I IFNs are thus critical in the development of efficient antiviral immune responses in humans, including the production of antiviral antibodies. PMID:18182457

  7. A Rapid, Self-confirming Assay for HIV: Simultaneous Detection of Anti-HIV Antibodies and Viral RNA

    PubMed Central

    Chen, Zongyuan; Zhu, Hui; Malamud, Daniel; Barber, Cheryl; Ongagna, Yhombi Yvon Serge; Yasmin, Rubina; Modak, Sayli; Janal, Malvin N.; Abrams, William R.; Montagna, Richard A.

    2016-01-01

    Objective We developed a microfluidic system to simultaneously detect host anti-HIV antibodies and viral RNA in the same specimen in order to satisfy two important diagnostic criteria, especially within resource-limited settings. First, the system can detect acute HIV infection and allow immediate confirmation of a seropositive screening result by detection of HIV RNA. It also addresses the well-known "seroconversion window" during early HIV infection when antibodies are not yet detectable and viral loads are at their highest. Methods We first developed and optimized two separate manual assays for the detection of host anti-HIV antibodies and viral RNA and then converted them to the microfluidic system. We optimized a commercially available serologic assay to run within the microfluidic device while we incorporated the isothermal LAMP assay to detect the presence of viral RNA. The microfluidic device and instrumentation were developed to simultaneously perform both assays without any user intervention. Results The finalized system consists of a disposable injection molded and film-laminated microfluidic CARD disposable device and a portable, software controlled instrument, which together can automatically perform all steps of both assays without any user intervention after the initial loading of samples and reagents. The microfluidic CARD cartridge has multiple microchannels, valves, pumps and reservoirs, which perform the immunoassay, isolates viral RNA for detection by magnetic bead based purification, and Reverse Transcriptase loop-mediated isothermal amplification (RT-LAMP). The microfluidic system was able to detect host anti-HIV antibodies and viral RNA in either a blood or saliva sample. Conclusion The ability to detect antibodies and simultaneously confirm a seropositive HIV-RNA result provides healthcare workers with a complete and accurate appraisal of a patient's infection status in the earliest stages of the disease and represents an important tool for

  8. Stimulation of the primary anti-HIV antibody response by IFN-alpha in patients with acute HIV-1 infection.

    PubMed

    Adalid-Peralta, Laura; Godot, Véronique; Colin, Céline; Krzysiek, Roman; Tran, Thi; Poignard, Pascal; Venet, Alain; Hosmalin, Anne; Lebon, Pierre; Rouzioux, Christine; Chene, Genevieve; Emilie, Dominique

    2008-04-01

    Type I IFNs are needed for the production of antiviral antibodies in mice; whether they also stimulate primary antibody responses in vivo during human viral infections is unknown. This was assessed in patients acutely infected with HIV-1 and treated with IFN-alpha2b. Patients with acute HIV-1 infection were randomized to receive antiretroviral therapy alone (Group A, n=60) or combined for 14 weeks with pegylated-IFN-alpha2b (Group B, n=30). Emergence of anti-HIV antibodies was monitored during 32 weeks by Western blot (WB) analyses of serum samples. IFN-alpha2b treatment stimulated the production of anti-HIV antibodies. On Week 32, 19 weeks after the last IFN-alpha2b administration, there were 8.5 (6.5-10.0) HIV WB bands (median, interquartile range) in Group B and 7.0 (5.0-10.0) bands in Group A (P=0.054), and band intensities were stronger in Group B (P<0.05 for p18, p24, p34, p40, and p55 HIV antigens). IFN-alpha2b treatment also increased circulating concentrations of the B cell-activating factor of the TNF family (P<0.001) and ex vivo production of IL-12 (P<0.05), reflecting its effect on innate immune cells. Withdrawal of antiretroviral treatment on Week 36 resulted in a lower rebound of HIV replication in Group B than in Group A (P<0.05). Therefore, type I IFNs stimulate the emerging anti-HIV immune response in patients with acute HIV-1 infection, resulting in an improved control of HIV replication. Type I IFNs are thus critical in the development of efficient antiviral immune responses in humans, including the production of antiviral antibodies.

  9. Anti-HIV-1 antibody-dependent cellular cytotoxicity mediated by hyperimmune bovine colostrum IgG.

    PubMed

    Kramski, Marit; Lichtfuss, Gregor F; Navis, Marjon; Isitman, Gamze; Wren, Leia; Rawlin, Grant; Center, Rob J; Jaworowski, Anthony; Kent, Stephen J; Purcell, Damian F J

    2012-10-01

    Antibodies with antibody-dependent cellular cytotoxicity (ADCC) activity play an important role in protection against HIV-1 infection, but generating sufficient amounts of antibodies to study their protective efficacy is difficult. HIV-specific IgG can be easily and inexpensively produced in large quantities using bovine colostrum. We previously vaccinated cows with HIV-1 envelope gp140 and elicited high titers of anti-gp140-binding IgG in colostrum. In the present study, we determined whether bovine antibodies would also demonstrate specific cytotoxic activity. We found that bovine IgG bind to Fcγ-receptors (FcγRs) on human neutrophils, monocytes, and NK cells in a dose-dependent manner. Antibody-dependent killing was observed in the presence of anti-HIV-1 colostrum IgG but not nonimmune colostrum IgG. Killing was dependent on Fc and FcγR interaction since ADDC activity was not seen with F(ab')(2) fragments. ADCC activity was primarily mediated by CD14(+) monocytes with FcγRIIa (CD32a) as the major receptor responsible for monocyte-mediated ADCC in response to bovine IgG. In conclusion, we demonstrate that bovine anti-HIV colostrum IgG have robust HIV-1-specific ADCC activity and therefore offer a useful source of antibodies able to provide a rapid and potent response against HIV-1 infection. This could assist the development of novel Ab-mediated approaches for prevention of HIV-1 transmission.

  10. Passive transfer of modest titers of potent and broadly neutralizing anti-HIV monoclonal antibodies block SHIV infection in macaques

    PubMed Central

    Shingai, Masashi; Donau, Olivia K.; Plishka, Ronald J.; Buckler-White, Alicia; Mascola, John R.; Nabel, Gary J.; Nason, Martha C.; Montefiori, David; Moldt, Brian; Poignard, Pascal; Diskin, Ron; Bjorkman, Pamela J.; Eckhaus, Michael A.; Klein, Florian; Mouquet, Hugo; Cetrulo Lorenzi, Julio Cesar; Gazumyan, Anna; Burton, Dennis R.; Nussenzweig, Michel C.

    2014-01-01

    It is widely appreciated that effective human vaccines directed against viral pathogens elicit neutralizing antibodies (NAbs). The passive transfer of anti–HIV-1 NAbs conferring sterilizing immunity to macaques has been used to determine the plasma neutralization titers, which must be present at the time of exposure, to prevent acquisition of SIV/HIV chimeric virus (SHIV) infections. We administered five recently isolated potent and broadly acting anti-HIV neutralizing monoclonal antibodies (mAbs) to rhesus macaques and challenged them intrarectally 24 h later with either of two different R5-tropic SHIVs. By combining the results obtained from 60 challenged animals, we determined that the protective neutralization titer in plasma preventing virus infection in 50% of the exposed monkeys was relatively modest (∼1:100) and potentially achievable by vaccination. PMID:25155019

  11. Anti-Leu3a induces combining site-related anti-idiotypic antibody without inducing anti-HIV activity.

    PubMed

    Reeves, J P; Buck, D; Berkower, I; Murphy, D; Epstein, S L

    1991-01-01

    Development of a vaccine for acquired immunodeficiency syndrome (AIDS) has proven difficult, and so alternative approaches such as idiotypic manipulation have been suggested. As applied to AIDS, this approach could involve immunizing with an anti-CD4 antibody resembling gp120, to induce anti-idiotypic antibodies which would bind to gp120. The CD4 binding site on gp120 is conserved, and so, such an immune response should protect against all variants. Induction of anti-human immunodeficiency virus (HIV) immunity has been reported using anti-Leu3a, and this result has led to testing in humans. Negative results obtained by others have been attributed to differences in immunization protocols. Because of the importance of this question, we reinvestigated the potential of anti-Leu3a to induce anti-HIV antibodies, compared with control immunizations with OKT4A (another anti-CD4 antibody) and the irrelevant Ig MOPC-21. Responses to anti-Leu3a showed induction of high-titer anti-idiotypic activity, and included combining-site-related activity. Yet sera showed no binding to gp160 above controls and no detectable neutralizing activity in a sensitive HIV plaque assay, so the anti-idiotypes induced were not internal images of CD4. We conclude that the pronounced anti-HIV responses reported with anti-Leu3a cannot be generalized, and thus that anti-Leu3a does not offer promise as an HIV vaccine. However, these results do not negate the promise of the idiotypic approach, and a vaccine for AIDS based on idiotype manipulation remains a possibility.

  12. Peptide Paratope Mimics of the Broadly Neutralizing HIV-1 Antibody b12.

    PubMed

    Haußner, Christina; Damm, Dominik; Nirschl, Sandra; Rohrhofer, Anette; Schmidt, Barbara; Eichler, Jutta

    2017-01-26

    The broadly neutralizing HIV-1 antibody b12 recognizes the CD4 binding site of the HIV-1 envelope glycoprotein gp120 and efficiently neutralizes HIV-1 infections in vitro and in vivo. Based on the 3D structure of a b12⋅gp120 complex, we have designed an assembled peptide (b12-M) that presents the parts of the three heavy-chain complementarity-determining regions (CDRs) of b12, which contain the contact sites of the antibody for gp120. This b12-mimetic peptide, as well as a truncated peptide presenting only two of the three heavy-chain CDRs of b12, were shown to recognize gp120 in a similar manner to b12, as well as to inhibit HIV-1 infection, demonstrating functional mimicry of b12 by the paratope mimetic peptides.

  13. Characterization of the third generation enzyme immunoassay IEA-HIV1/2-III for the detection of anti-HIV specific antibodies in human sera.

    PubMed

    Rayevskaya, G; Pilipenko, V G; Tkáciková, L; Spivak, N Y; Mikula, I; Chumak, R M

    2000-01-01

    The sensitivity and specificity of the developed anti-HIV1/2 third generation enzyme immunoassay, the IEA-HIV1/2-III, was examined. The test system for the detection of anti-HIV antibodies included peroxidase-conjugated HIV-specific recombinant Gag protein fragments (epitopes of p24 and p17 proteins), Env-1 (epitopes of p41 and p120 proteins), and Env-2 (p36 epitopes). Sensitivity was evaluated with 346 sera from HIV1-seropositive subjects, Anti-HIV1 Low Titer panels no. 10 and PRB-106 and seropositive panel PRB-931 in comparison with other third- and second-generation assays. The IEA-HIV1/2-III assays are characterized with high sensitivity comparable to the other third generation assays and the better sensitivity with respect to the second generation test-kit to determine HIV-specific antibodies in human sera. The specificity was determined using three hundred sixty-seven potentially cross-reactive samples (but negative for anti-HIV1/2). Only one specimen among them was reactive by IEA-HIV1/2-III.

  14. Promise and problems associated with the use of recombinant AAV for the delivery of anti-HIV antibodies

    PubMed Central

    Fuchs, Sebastian P; Desrosiers, Ronald C

    2016-01-01

    Attempts to elicit antibodies with potent neutralizing activity against a broad range of human immunodeficiency virus (HIV) isolates have so far proven unsuccessful. Long-term delivery of monoclonal antibodies (mAbs) with such activity is a creative alternative that circumvents the need for an immune response and has the potential for creating a long-lasting sterilizing barrier against HIV. This approach is made possible by an incredible array of potent broadly neutralizing antibodies (bnAbs) that have been identified over the last several years. Recombinant adeno-associated virus (rAAV) vectors are ideally suited for long-term delivery for a variety of reasons. The only products made from rAAV are derived from the transgenes that are put into it; as long as those products are not viewed as foreign, expression from muscle tissue may continue for decades. Thus, use of rAAV to achieve long-term delivery of anti-HIV mAbs with potent neutralizing activity against a broad range of HIV-1 isolates is emerging as a promising concept for the prevention or treatment of HIV-1 infection in humans. Experiments in mice and monkeys that have demonstrated protective efficacy against AIDS virus infection have raised hopes for the promise of this approach. However, all published experiments in monkeys have encountered unwanted immune responses to the AAV-delivered antibody, and these immune responses appear to limit the levels of delivered antibody that can be achieved. In this review, we highlight the promise of rAAV-mediated antibody delivery for the prevention or treatment of HIV infection in humans, but we also discuss the obstacles that will need to be understood and solved in order for the promise of this approach to be realized. PMID:28197421

  15. Array-in-well platform-based multiplex assay for the simultaneous detection of anti-HIV- and treponemal-antibodies, and Hepatitis B surface antigen.

    PubMed

    Talha, Sheikh M; Saviranta, Petri; Hattara, Liisa; Vuorinen, Tytti; Hytönen, Jukka; Khanna, Navin; Pettersson, Kim

    2016-02-01

    Multiplex assays detecting sets of related clinical analytes simultaneously can save considerable amount of time and resources. Array-in-well (AIW) is a powerful platform for the multiplex detection of different analytes where microarrays can be printed at the bottom of microtiter wells, thus combining the potential of microarrays with the ease of handling microtiter wells. We have developed a single-step AIW assay for the simultaneous screening of HIV, Treponema pallidum subspecies pallidum (causing syphilis) and Hepatitis B virus infections targeting the specific detection of anti-HIV- and treponemal-antibodies and Hepatitis B surface antigen (HBsAg), respectively, using two different fluorescent label technologies i.e. DyLight 633 and europium nanoparticle. Double-antigen assay formats were used for anti-HIV- and treponemal-antibody detection that can simultaneously detect both IgG and IgM, and thus reduce the window period of detection. AIW assay was evaluated with well characterized serum/plasma samples (n=111), and the qualitative results were in near complete agreement with those of the reference assays. The AIW assay exhibited 100% sensitivities for all three analytes, and 100% specificities for anti-HIV antibodies and HBsAg, and 98.6% specificity for treponemal antibodies. The limit of detection of HBsAg in AIW assay was 0.18 ng/ml. This high performing AIW assay has the potential to be used as a multiplex screening test for these three infections.

  16. Expressing anti-HIV VRC01 antibody using the murine IgG1 secretion signal in Pichia pastoris.

    PubMed

    Aw, Rochelle; McKay, Paul F; Shattock, Robin J; Polizzi, Karen M

    2017-12-01

    The use of the recombinant expression platform Pichia pastoris to produce pharmaceutically important proteins has been investigated over the past 30 years. Compared to mammalian cultures, expression in P. pastoris is cheaper and faster, potentially leading to decreased costs and process development times. Product yields depend on a number of factors including the secretion signal chosen for expression, which can influence the host cell response to recombinant protein production. VRC01, a broadly neutralising anti-HIV antibody, was expressed in P. pastoris, using the methanol inducible AOX1 promoter for both the heavy and light chains. Titre reached up to 3.05 μg mL(-1) in small scale expression. VRC01 was expressed using both the α-mating factor signal peptide from Saccharomyces cerevisiae and the murine IgG1 signal peptide. Surprisingly, using the murine IgG1 signal peptide resulted in higher yield of antibody capable of binding gp140 antigen. Furthermore, we evaluated levels of secretory stress compared to the untransformed wild-type strain and show a reduced level of secretory stress in the murine IgG1 signal peptide strains versus those containing the α-MF signal peptide. As bottlenecks in the secretory pathway are often the limiting factor in protein secretion, reduced levels of secretory stress and the higher yield of functional antibody suggest the murine IgG1 signal peptide may lead to better protein folding and secretion. This work indicates the possibilities for utilising the murine IgG1 signal peptide for a range of antibodies, resulting in high yields and reduced cellular stress.

  17. Global Structure of HIV-1 Neutralizing Antibody IgG1 b12 is Asymmetric

    SciTech Connect

    Ashish, F.; Solanki, A; Boone, C; Krueger, J

    2010-01-01

    Human antibody IgG1 b12 is one of the four antibodies known to neutralize a broad range of human immunodeficiency virus-1. The crystal structure of this antibody displayed an asymmetric disposition of the Fab arms relative to its Fc portion. Comparison of structures solved for other IgG1 antibodies led to a notion that crystal packing forces entrapped a 'snap-shot' of different conformations accessible to this antibody. To elucidate global structure of this unique antibody, we acquired small-angle X-ray scattering data from its dilute solution. Data analysis indicated that b12 adopts a bilobal globular structure in solution with a radius of gyration and a maximum linear dimension of {approx}54 and {approx}180 {angstrom}, respectively. Extreme similarity between its solution and crystal structure concludes that non-flexible, asymmetric shape is an inherent property of this rare antibody.

  18. Overcoming the Constraints of Anti-HIV/CD89 Bispecific Antibodies That Limit Viral Inhibition

    PubMed Central

    Duval, Mark; Posner, Marshall R.

    2016-01-01

    Innovative strategies are necessary to maximize the clinical application of HIV neutralizing antibodies. To this end, bispecific constructs of human antibody F240, reactive with well-conserved gp41 epitope and antibody 14A8, reactive with the IgA receptor (CD89) on effector cells, were constructed. A F240 × 14A8 bispecific single chain variable region (scFv) molecule was constructed by linking two scFvs using a conventional GGGGS linker. Despite immunoreactivity with HIV gp41 and neutrophils, this bispecific scFv failed to inhibit HIV infection. This is in sharp contrast to viral inhibition using a chemical conjugate of the Fab of these two antibodies. Therefore, we constructed two novel Fab-like bispecific antibody molecules centered on fusion of the IgG1 CH1 domain or CH1-hinge domain to the C-terminus of F240scFv and fusion of the kappa chain CL domain to the C-terminus of 14A8scFv. Both Bi-Fab antibodies showed significant ADCVI activity for multiple clade B and clade C isolates by arming the neutrophils to inhibit HIV infection. The approach presented in this study is unique for HIV immunotherapy in that the impetus of neutralization is to arm and mobilize PMN to destroy HIV and HIV infected cells. PMID:27419146

  19. [Retrospective evaluation of HBsAg, anti-HCV, anti-HIV and syphilis reagin antibody seropositivity in blood donors at the Trabzon Farabi Hospital].

    PubMed

    Aydin, Faruk; Cubukçu, Kivanç; Yetişkul, Serpil; Yazici, Yelda; Kaklikkaya, Neşe

    2002-01-01

    Transfusion of blood and blood products is a widely used method for therapy in medicine, however it may result with the transmission of infectious agents from donor to recipient. In order to achieve safe blood transfusions and to minimize post-transfusion infections, several screening tests for infectious agents are routinely done all around the world as well as in our country. In this study, HBsAg, anti-HCV, anti-HIV and syphilis reagin antibody tests results have been retrospectively evaluated for 33.766 blood donors during January 1, 1997 to December 31, 2000 in Blood Center of Farabi Hospital, Black Sea Technical University. Testing for HBsAg, anti-HIV and anti-HCV has been done by using commercially available micro and/or macro enzyme immunoassays, and syphilis reagin antibody test by latex agglutination (RPR) method. The indeterminate results were confirmed by retesting of sera with microparticle enzyme immunoassay and Western blot methods. As a result, in 1331 (3.94%) subjects HBsAg, in 250 (0.74%) subjects anti-HCV, and in 161 (0.47%) subjects RPR were found positive. Twenty samples which have had the results in gray-zone for anti-HIV, have been found negative with the confirmation tests.

  20. Sequential Immunization Elicits Broadly Neutralizing Anti-HIV-1 Antibodies in Ig Knockin Mice.

    PubMed

    Escolano, Amelia; Steichen, Jon M; Dosenovic, Pia; Kulp, Daniel W; Golijanin, Jovana; Sok, Devin; Freund, Natalia T; Gitlin, Alexander D; Oliveira, Thiago; Araki, Tatsuya; Lowe, Sarina; Chen, Spencer T; Heinemann, Jennifer; Yao, Kai-Hui; Georgeson, Erik; Saye-Francisco, Karen L; Gazumyan, Anna; Adachi, Yumiko; Kubitz, Michael; Burton, Dennis R; Schief, William R; Nussenzweig, Michel C

    2016-09-08

    A vaccine that elicits broadly neutralizing antibodies (bNAbs) against HIV-1 is likely to be protective, but this has not been achieved. To explore immunization regimens that might elicit bNAbs, we produced and immunized mice expressing the predicted germline PGT121, a bNAb specific for the V3-loop and surrounding glycans on the HIV-1 spike. Priming with an epitope-modified immunogen designed to activate germline antibody-expressing B cells, followed by ELISA-guided boosting with a sequence of directional immunogens, native-like trimers with decreasing epitope modification, elicited heterologous tier-2-neutralizing responses. In contrast, repeated immunization with the priming immunogen did not. Antibody cloning confirmed elicitation of high levels of somatic mutation and tier-2-neutralizing antibodies resembling the authentic human bNAb. Our data establish that sequential immunization with specifically designed immunogens can induce high levels of somatic mutation and shepherd antibody maturation to produce bNAbs from their inferred germline precursors.

  1. Broadly Neutralizing Anti-HIV Antibodies Prevent HIV Infection of Mucosal Tissue Ex Vivo.

    PubMed

    Scott, Yanille M; Park, Seo Young; Dezzutti, Charlene S

    2016-02-01

    Broadly neutralizing monoclonal antibodies (nAbs) specific for HIV are being investigated for use in HIV prevention. Due to their ability to inhibit HIV attachment to and entry into target cells, nAbs may be suitable for use as topical HIV microbicides. As such, they would present an alternative intervention for individuals who may not benefit from using antiretroviral-based products for HIV prevention. We theorize that nAbs can inhibit viral transmission through mucosal tissue, thus reducing the incidence of HIV infection. The efficacy of the PG9, PG16, VRC01, and 4E10 antibodies was evaluated in an ex vivo human model of mucosal HIV transmission. nAbs reduced HIV transmission, causing 1.5- to 2-log10 reductions in HIV replication in ectocervical tissues and ≈3-log10 reductions in HIV replication in colonic tissues over 21 days. These antibodies demonstrated greater potency in colonic tissues, with a 50-fold higher dose being required to reduce transmission in ectocervical tissues. Importantly, nAbs retained their potency and reduced viral transmission in the presence of whole semen. No changes in tissue viability or immune activation were observed in colonic or ectocervical tissue after nAb exposure. Our data suggest that topically applied nAbs are safe and effective against HIV infection of mucosal tissue and support further development of nAbs as a topical microbicide that could be used for anal as well as vaginal protection.

  2. Broadly Neutralizing Anti-HIV Antibodies Prevent HIV Infection of Mucosal Tissue Ex Vivo

    PubMed Central

    Scott, Yanille M.; Park, Seo Young

    2015-01-01

    Broadly neutralizing monoclonal antibodies (nAbs) specific for HIV are being investigated for use in HIV prevention. Due to their ability to inhibit HIV attachment to and entry into target cells, nAbs may be suitable for use as topical HIV microbicides. As such, they would present an alternative intervention for individuals who may not benefit from using antiretroviral-based products for HIV prevention. We theorize that nAbs can inhibit viral transmission through mucosal tissue, thus reducing the incidence of HIV infection. The efficacy of the PG9, PG16, VRC01, and 4E10 antibodies was evaluated in an ex vivo human model of mucosal HIV transmission. nAbs reduced HIV transmission, causing 1.5- to 2-log10 reductions in HIV replication in ectocervical tissues and ≈3-log10 reductions in HIV replication in colonic tissues over 21 days. These antibodies demonstrated greater potency in colonic tissues, with a 50-fold higher dose being required to reduce transmission in ectocervical tissues. Importantly, nAbs retained their potency and reduced viral transmission in the presence of whole semen. No changes in tissue viability or immune activation were observed in colonic or ectocervical tissue after nAb exposure. Our data suggest that topically applied nAbs are safe and effective against HIV infection of mucosal tissue and support further development of nAbs as a topical microbicide that could be used for anal as well as vaginal protection. PMID:26596954

  3. Autoreactivity and Exceptional CDR Plasticity (but Not Unusual Polyspecificity) Hinder Elicitation of the Anti-HIV Antibody 4E10

    PubMed Central

    Finton, Kathryn A. K.; Larimore, Kevin; Larman, H. Benjamin; Friend, Della; Correnti, Colin; Rupert, Peter B.; Elledge, Stephen J.; Greenberg, Philip D.; Strong, Roland K.

    2013-01-01

    The broadly-neutralizing anti-HIV antibody 4E10 recognizes an epitope in the membrane-proximal external region of the HIV envelope protein gp41. Previous attempts to elicit 4E10 by vaccination with envelope-derived or reverse-engineered immunogens have failed. It was presumed that the ontogeny of 4E10-equivalent responses was blocked by inherent autoreactivity and exceptional polyreactivity. We generated 4E10 heavy-chain knock-in mice, which displayed significant B cell dysregulation, consistent with recognition of autoantigen/s by 4E10 and the presumption that tolerance mechanisms may hinder the elicitation of 4E10 or 4E10-equivalent responses. Previously proposed candidate 4E10 autoantigens include the mitochondrial lipid cardiolipin and a nuclear splicing factor, 3B3. However, using carefully-controlled assays, 4E10 bound only weakly to cardiolipin-containing liposomes, but also bound negatively-charged, non-cardiolipin-containing liposomes comparably poorly. 4E10/liposome binding was predominantly mediated by electrostatic interactions rather than presumed hydrophobic interactions. The crystal structure of 4E10 free of bound ligands showed a dramatic restructuring of the combining site, occluding the HIV epitope binding site and revealing profound flexibility, but creating an electropositive pocket consistent with non-specific binding of phospholipid headgroups. These results strongly suggested that antigens other than cardiolipin mediate 4E10 autoreactivity. Using a synthetic peptide library spanning the human proteome, we determined that 4E10 displays limited and focused, but unexceptional, polyspecificity. We also identified a novel autoepitope shared by three ER-resident inositol trisphosphate receptors, validated through binding studies and immunohistochemistry. Tissue staining with 4E10 demonstrated reactivity consistent with the type 1 inositol trisphosphate receptor as the most likely candidate autoantigen, but is inconsistent with splicing factor 3B3

  4. Anti-HIV antibody in saliva: an assessment of the role of the components of saliva, testing methodologies and collection systems.

    PubMed

    Lamey, P J; Nolan, A; Follett, E A; Coote, I; MacFarlane, T W; Kennedy, D H; Connell, A; Parry, J V

    1996-03-01

    The various components of saliva, namely mixed saliva, parotid saliva, submandibular saliva, crevicular fluid and minor (labial) gland secretions, were collected from 63 known HIV antibody seropositive patients. A commercial test system, Wellcozyme HIV 1+2, and an antibody capture ELISA (GACELISA), were compared for sensitivity against all components. Sensitivity of the GACELISA system was 100% in 123 mixed saliva, 121 parotid saliva and 127 labial fluid samples, and 98% in 99 submandibular samples and 127 crevicular fluid samples. Respective figures for Wellcozyme 1+2 were 92%, 55%, 73%, 66% and 63%. Mixed saliva was most easily, conveniently and effectively collected using a plain Salivette. In 241 Salivette samples examined from the 63 patients, GACELISA proved 100% sensitive, and Wellcozyme 95% sensitive. Another form of Salivette impregnated with citric acid was unsuitable for GACELISA and gave a false negative value of 45%. In 197 samples from the gingival margin taken by a dry swab, GACELISA showed a sensitivity of 98% and Wellcozyme 81%. The most sensitive method for demonstrating anti-HIV antibody in saliva is to collect mixed saliva with the plain Salivette system and assay anti-HIV antibody levels by GACELISA.

  5. Latex bead immobilisation in PDMS matrix for the detection of p53 gene point mutation and anti-HIV-1 capsid protein antibodies.

    PubMed

    Marquette, Christophe A; Degiuli, Agnès; Imbert-Laurenceau, Emmanuelle; Mallet, Francois; Chaix, Carole; Mandrand, Bernard; Blum, Loïc J

    2005-03-01

    Two diagnostic chemiluminescent biochips were developed for either the detection of p53 gene point mutation or the serological detection of anti-HIV-1 p24 capsid protein. Both biochips were composed of 24 microarrays of latex beads spots (4x4) (150 microm in diameter, 800 microm spacing) entrapped in a poly(dimethylsiloxane) elastomer (PDMS). The latex beads, bearing oligonucleotide sequences or capsid protein, were spotted with a conventional piezoelectric spotter and subsequently transferred at the PDMS interface. The electron microscopy observation of the biochips showed how homogeneous and well distributed the spots could be. Point mutation detection on the codon 273 of the p53 gene was performed on the basis of the melting temperature difference between the perfect match sequence and the one base pair mismatch sequence. The hybridisation of a 20-mer oligonucleotide form the codon 273 including a one base pair mutation in its sequence on a biochip arrayed with non-muted and the muted complementary sequences, enabled a clear discrimination at 56 degrees C between muted and wild sequences. Moreover, the quantitative measurement of the amount of muted sequence in a sample was possible in the range 0.4-4 pmol. Serological measurement of anti-HIV-1 p24 capsid protein on the biochip, prepared with 1-microm-diameter latex beads, enabled the detection of monoclonal antibodies in the range 1.55-775 ng mL(-1). Such a range could be lowered to 0.775 ng mL(-1) when using 50-nm-diameter beads, which generated a higher specific surface. The validation of the biochip for the detection of anti-HIV-1 capsid protein antibodies was performed in human sera from seropositive and seronegative patients. The positivity of the sera was easily discriminated at serum dilutions below 1:1,000.

  6. [Significance of the control serum measurement in infectious disease tests--a case of lot-to-lot variation of anti-HIV antibody assay kit].

    PubMed

    Sasaki, Miho; Sasaki, Kenji

    2002-07-01

    We are using infectious disease test kits consisting of positive serum diluted with negative pooled serum (P-S) and positive control (P-C). In two anti-HIV antibody tests the results for both P-S and P-C fluctuated between positive and negative depending on the lot No. of the reagent. In Western blot tests carried out to confirm the tests, the P-C was found to be positive and the P-S tests were both inconclusive. We speculated that the P-S had very weak antibodies that reacted differently from patient samples. Manufacturers of such kits, however, must supply reagents with appropriate reactivity, so it is important that they be informed of inconsistencies that could invalidate cut-off values and lead to false-positives and false-negatives.

  7. Improved specificity of in vitro anti-HIV antibody production: implications for diagnosis and timing of transmission in infants born to HIV-seropositive mothers.

    PubMed

    Wang, X P; Paul, M; Tetali, S; Abrams, E; Bamji, M; Gulick, L; Chirmule, N; Oyaizu, N; Bakshi, S; Pahwa, S

    1994-06-01

    In vitro anti-HIV antibody production (IVAP), initially introduced as a method for diagnosis of human immunodeficiency virus type 1 (HIV-1) infection in infants, has been limited in its application because of poor specificity and sensitivity early in life. The aims of this study were to improve the specificity of the IVAP assay and to evaluate its sensitivity in conjunction with assays of HIV culture, polymerase chain reaction (PCR), and p24 antigen. To prevent false-positive reactions resulting from maternal serum-derived cytophilic anti-HIV IgG, additional preculture and washing steps for peripheral blood mononuclear cells (PBMCs) were introduced that resulted in dramatic improvement in specificity of IVAP. The sensitivity of the revised IVAP at age < 3 months in 20 infected infants was, however, only 25%; of 15 infected infants initially negative in IVAP, 13 became positive at a mean estimated age of 4.4 +/- 1.8 months. When correlated with virological assays, a failure to respond in IVAP at age < 1 month was often associated with negative virological identification, whereas a positive IVAP response at age < 3 months was always associated with positive results in all virological assays. Moreover, conversion from negative IVAP to positive responses occurred subsequent to, and not concurrently with, a positive virological identification of infected infants. The revised IVAP methodology renders this assay potentially useful as an additional tool not only for the diagnosis of HIV infection, but for estimating timing of maternal-infant HIV transmission as well.

  8. Antibody Conjugation Approach Enhances Breadth and Potency of Neutralization of Anti-HIV-1 Antibodies and CD4-IgG

    PubMed Central

    Gavrilyuk, Julia; Ban, Hitoshi; Uehara, Hisatoshi; Sirk, Shannon J.; Saye-Francisco, Karen; Cuevas, Angelica; Zablowsky, Elise; Oza, Avinash; Seaman, Michael S.; Burton, Dennis R.

    2013-01-01

    Broadly neutralizing antibodies PG9 and PG16 effectively neutralize 70 to 80% of circulating HIV-1 isolates. In this study, the neutralization abilities of PG9 and PG16 were further enhanced by bioconjugation with aplaviroc, a small-molecule inhibitor of virus entry into host cells. A novel air-stable diazonium hexafluorophosphate reagent that allows for rapid, tyrosine-selective functionalization of proteins and antibodies under mild conditions was used to prepare a series of aplaviroc-conjugated antibodies, including b12, 2G12, PG9, PG16, and CD4-IgG. The conjugated antibodies blocked HIV-1 entry through two mechanisms: by binding to the virus itself and by blocking the CCR5 receptor on host cells. Chemical modification did not significantly alter the potency of the parent antibodies against nonresistant HIV-1 strains. Conjugation did not alter the pharmacokinetics of a model IgG in blood. The PG9-aplaviroc conjugate was tested against a panel of 117 HIV-1 strains and was found to neutralize 100% of the viruses. PG9-aplaviroc conjugate IC50s were lower than those of PG9 in neutralization studies of 36 of the 117 HIV-1 strains. These results support this new approach to bispecific antibodies and offer a potential new strategy for combining HIV-1 therapies. PMID:23427154

  9. Autoimmune anti-HIV-1gp120 antibody with antiidiotype-like activity in sera and immune complexes of HIV-1-related immunologic thrombocytopenia.

    PubMed Central

    Karpatkin, S; Nardi, M

    1992-01-01

    Autoimmune antiidiotype-like antibody (Ab2) directed against anti-HIV-1gp120 (Ab1) was found in high titer in the sera of 10 consecutive homosexual and 11 narcotic addict HIV-1-related immunologic thrombocytopenia (HIV-1-ITP) patients, was barely detectable in 10 nonthrombocytopenic HIV-1 sero-positive individuals, and was not detectable in 5 normal subjects by use of a solid-phase RIA. Reactivity of autologous Ab2 for Ab1 was 4-120-fold greater than Ab2 for homologous Ab1. Affinity-purified Ab2 did not block the binding of affinity-purified Ab1 to its HIV-1gp120 epitopes on immunoblot, indicating the absence of "internal image" antiidiotype. Both Ab1 and Ab2 are precipitable from sera with polyethylene glycol (PEG) and present in a macromolecular complex that is excluded by gel filtration on G200 and contains IgG, IgM, C3, and the anti-F(ab')2 antiidiotype-like complex. PEG-precipitable complexes bind to platelets in a saturation-dependent manner. Neither affinity-purified Ab1 nor Ab2 binds to platelets. However, the combination of Ab1 and Ab2 (preincubated for 2 h at 22 degrees C) binds to platelets in a saturation-dependent manner at an optimum ratio range of 10-20:1. Ab2 reactivity correlates with serum PEG-precipitable immune complex level (r = 0.91; P less than 0.001) and with thrombocytopenia (r = 0.89; P less than 0.001). We suggest that the anti-HIV-1gp120 antiidiotype-like complex contributes to the markedly elevated platelet Ig and C3 level of HIV-1-ITP patients and propose that this may contribute to their thrombocytopenia. Images PMID:1737832

  10. Vitamin B12 deficiency with intrinsic factor antibodies in an infant with poor growth and developmental delay.

    PubMed

    McNeil, Kathleen; Chowdhury, Dhiman; Penney, Lynette; Rashid, Mohsin

    2014-02-01

    Vitamin B12 deficiency is very rare in infants and may lead to serious hematological and neurodevelopmental abnormalities. The present article describes a case involving a seven-month-old boy with severe vitamin B12 deficiency, likely caused by juvenile pernicious anemia, an entity rarely described. The child presented with feeding intolerance, poor growth and developmental delay. He was noted to have macrocytic anemia, a markedly low serum vitamin B12 level, and elevated homocysteine and methylmalonic acid levels. Antibodies to intrinsic factor were positive. The mother was healthy, with normal vitamin B12 status. Therapy with vitamin B12 supplements led to excellent recovery of symptoms. Vitamin B12 deficiency should be considered in children presenting with failure to thrive, especially when compounded with neurological symptoms. Early diagnosis and adequate treatment is essential to avoid serious complications.

  11. A solution NMR study of the interactions of oligomannosides and the anti-HIV-1 2G12 antibody reveals distinct binding modes for branched ligands.

    PubMed

    Enríquez-Navas, Pedro M; Marradi, Marco; Padro, Daniel; Angulo, Jesús; Penadés, Soledad

    2011-02-01

    The structural and affinity details of the interactions of synthetic oligomannosides, linear (di-, tri-, and tetra-) and branched (penta- and hepta-), with the broadly neutralizing anti-HIV-1 antibody 2G12 (HIV=human immunodeficiency virus) have been investigated in solution by using ligand-based NMR techniques, specifically saturation transfer difference (STD) NMR spectroscopy and transferred NOE experiments. Linear oligomannosides show similar binding modes to the antibody, with the nonreducing terminal disaccharide Manα(1→2)Man (Man=mannose) making the closest protein/ligand contacts in the bound state. In contrast, the branched pentamannoside shows two alternate binding modes, involving both ligand arms (D2- and D3-like), a dual binding description of the molecular recognition of this ligand by 2G12 in solution that differs from the single binding mode deduced from X-ray studies. On the contrary, the antibody shows an unexpected selectivity for one arm (D1-like) of the other branched ligand (heptamannoside). This result explains the previously reported lack of affinity enhancement relative to that of the D1-like tetramannoside. Single-ligand STD NMR titration experiments revealed noticeable differences in binding affinities among the linear and branched ligands in solution, with the latter showing decreased affinity. Among the analyzed series of ligands, the strongest 2G12 binders were the linear tri- and tetramannosides because both show similar affinity for the antibody. These results demonstrate that NMR spectroscopic techniques can deliver abundant structural, dynamics, and affinity information for the characterization of oligomannose-2G12 binding in solution, thus complementing, and, as in the case of the pentamannoside, extending, the structural view from X-ray crystallography. This information is of key importance for the development of multivalent synthetic gp120 high-mannose glycoconjugate mimics in the context of vaccine development.

  12. Epitope Mapping of Ibalizumab, a Humanized Anti-CD4 Monoclonal Antibody with Anti-HIV-1 Activity in Infected Patients▿

    PubMed Central

    Song, Ruijiang; Franco, David; Kao, Chia-Ying; Yu, Faye; Huang, Yaoxing; Ho, David D.

    2010-01-01

    Ibalizumab is a humanized monoclonal antibody that binds human CD4, the primary receptor for human immunodeficiency virus type 1 (HIV-1). With its unique specificity for domain 2 of CD4, this antibody potently and broadly blocks HIV-1 infection in vitro by inhibiting a postbinding step required for viral entry but without interfering with major histocompatibility complex class II (MHC-II)-mediated immune function. In clinical trials, ibalizumab has demonstrated anti-HIV-1 activity in patients without causing immunosuppression. Thus, a characterization of the ibalizumab epitope was conducted in an attempt to gain insight into the underlying mechanism of its antiviral activity as well as its safety profile. By studying mouse/human chimeric CD4 molecules and site-directed point mutants of CD4, amino acids L96, P121, P122, and Q163 in domain 2 were found to be important for ibalizumab binding, with E77 and S79 in domain 1 also contributing. All these residues appear to cluster on the interface between domains 1 and 2 of human CD4 on a surface opposite the site where gp120 and the MHC-II molecule bind on domain 1. Separately, the epitope of M-T441, a weakly neutralizing mouse monoclonal antibody that competes with ibalizumab, was localized entirely within domain 2 on residues 123 to 125 and 138 to 140. The results reported herein not only provide an appreciation for why ibalizumab has not had significant adverse immunological consequences in infected patients to date but also raise possible steric hindrance mechanisms by which this antibody blocks HIV-1 entry into a CD4-positive cell. PMID:20463063

  13. Epitope mapping of ibalizumab, a humanized anti-CD4 monoclonal antibody with anti-HIV-1 activity in infected patients.

    PubMed

    Song, Ruijiang; Franco, David; Kao, Chia-Ying; Yu, Faye; Huang, Yaoxing; Ho, David D

    2010-07-01

    Ibalizumab is a humanized monoclonal antibody that binds human CD4, the primary receptor for human immunodeficiency virus type 1 (HIV-1). With its unique specificity for domain 2 of CD4, this antibody potently and broadly blocks HIV-1 infection in vitro by inhibiting a postbinding step required for viral entry but without interfering with major histocompatibility complex class II (MHC-II)-mediated immune function. In clinical trials, ibalizumab has demonstrated anti-HIV-1 activity in patients without causing immunosuppression. Thus, a characterization of the ibalizumab epitope was conducted in an attempt to gain insight into the underlying mechanism of its antiviral activity as well as its safety profile. By studying mouse/human chimeric CD4 molecules and site-directed point mutants of CD4, amino acids L96, P121, P122, and Q163 in domain 2 were found to be important for ibalizumab binding, with E77 and S79 in domain 1 also contributing. All these residues appear to cluster on the interface between domains 1 and 2 of human CD4 on a surface opposite the site where gp120 and the MHC-II molecule bind on domain 1. Separately, the epitope of M-T441, a weakly neutralizing mouse monoclonal antibody that competes with ibalizumab, was localized entirely within domain 2 on residues 123 to 125 and 138 to 140. The results reported herein not only provide an appreciation for why ibalizumab has not had significant adverse immunological consequences in infected patients to date but also raise possible steric hindrance mechanisms by which this antibody blocks HIV-1 entry into a CD4-positive cell.

  14. Enhanced clearance of HIV-1-infected cells by anti-HIV-1 broadly neutralizing antibodies in vivo

    PubMed Central

    Lu, Ching-Lan; Murakowski, Dariusz K.; Bournazos, Stylianos; Schoofs, Till; Sarkar, Debolina; Halper-Stromberg, Ariel; Horwitz, Joshua A.; Nogueira, Lilian; Golijanin, Jovana; Gazumyan, Anna; Ravetch, Jeffrey V.; Caskey, Marina; Chakraborty, Arup K.; Nussenzweig, Michel C.

    2016-01-01

    Anti-retroviral drugs and antibodies limit HIV-1 infection by interfering with the viral life-cycle. In addition, antibodies also have the potential to guide host immune effector cells to kill HIV-1 infected cells. Examination of the kinetics of HIV-1 suppression in infected individuals by passively administered 3BNC117, a broadly neutralizing antibody (bNAb), suggested that the effects of the antibody are not limited to free viral clearance and blocking new infection, but also include acceleration of infected cell clearance. Consistent with these observations, we find that bNAbs can target CD4+ T cells infected with patient viruses and decrease their in vivo half-lives by a mechanism that requires FcγR engagement in a humanized mouse model. The results indicate that passive immunotherapy can accelerate elimination of HIV-1 infected cells. PMID:27199430

  15. λ Light Chain Bias Associated With Enhanced Binding and Function of Anti-HIV Env Glycoprotein Antibodies.

    PubMed

    Sajadi, Mohammad M; Farshidpour, Maham; Brown, Eric P; Ouyang, Xin; Seaman, Michael S; Pazgier, Marzena; Ackerman, Margaret E; Robinson, Harriet; Tomaras, Georgia; Parsons, Matthew S; Charurat, Manhattan; DeVico, Anthony L; Redfield, Robert R; Lewis, George K

    2016-01-01

    The humoral response to human immunodeficiency virus (HIV) remains incompletely understood. In this report, we describe biased λ light chain use during the HIV Env glycoprotein (Env) response in HIV infection and vaccination. We examined HIV Env binding (and neutralization) in the context of light chain use in subjects with acute HIV infection, chronic HIV infection, and among HIV vaccinees. In all populations tested, there was a λ chain bias for HIV Env binding antibodies, compared with other HIV antigens (such as p24) or tetanus toxoid. In subjects with chronic HIV infection, a λ bias was noted for neutralization, with λ antibodies accounting for up to 90% of all neutralization activity observed. This is the first report of antibody function in a human infection being tied to light chain use. In HIV infection, antibodies expressing λ light chains tended to have longer CDRL3s, increased light chain contact with HIV Env, and less hypermutation in the heavy chain, compared with antibodies using the κ light chain. These data also support an evolutionary model for the understanding the various κ to λ light chain ratios observed across species and suggest that the λ light chain bias against HIV provides the host an advantage in developing a more efficient humoral response.

  16. Characterization of anti-HIV-1 neutralizing and binding antibodies in chronic HIV-1 subtype C infection

    PubMed Central

    Archary, Derseree; Rong, Rong; Gordon, Michelle L; Boliar, Saikat; Madiga, Maphuti; Gray, Elin S; Dugast, Anne-Sophie; Hermanus, Tandile; Goulder, Philip JR; Coovadia, Hoosen M; Werner, Lise; Morris, Lynn; Alter, Galit; Derdeyn, Cynthia A; Ndung'u, Thumbi

    2012-01-01

    Neutralizing (nAbs) and high affinity binding antibodies may be critical for an efficacious HIV-1 vaccine. We characterized virus-specific nAbs and binding antibody responses over 21 months in eight HIV-1 subtype C chronically infected individuals with heterogeneous rates of disease progression. Autologous nAb titers at study exit were significantly higher compared to contemporaneous responses at study entry (p=0.002) and exit (p=0.01). NAb IC50 titers correlated inversely with V1-V2 length (p=0.04). Significant differences in breadth and potencies were noted against subtype C compared to subtype A (p= 0.03 and p=0.01) or subtype B (p= 0.03; p=0.05) viruses respectively. IgG binding affinity for gp41 was higher than for gp120 (p=0.0002). IgG-FcγR1 affinity was significantly higher than FcγRIIIa (p<0.005) at study entry and FcγRIIb (p<0.05) or FcγRIIIa (p<0.005) at study exit. Evolving IgG binding suggests alteration of immune function mediated by binding antibodies. Evolution of nAbs was a potential marker of HIV-1 disease progression. PMID:22995189

  17. Potent and synergistic neutralization of human immunodeficiency virus (HIV) type 1 primary isolates by hyperimmune anti-HIV immunoglobulin combined with monoclonal antibodies 2F5 and 2G12.

    PubMed

    Mascola, J R; Louder, M K; VanCott, T C; Sapan, C V; Lambert, J S; Muenz, L R; Bunow, B; Birx, D L; Robb, M L

    1997-10-01

    Three antibody reagents that neutralize primary human immunodeficiency virus type 1 (HIV-1) isolates were tested for magnitude and breadth of neutralization when used alone or in double or triple combinations. Hyperimmune anti-HIV immunoglobulin (HIVIG) is derived from the plasma of HIV-1-infected donors, and monoclonal antibodies (MAbs) 2F5 and 2G12 bind to distinct regions of the HIV-1 envelope glycoprotein. The antibodies were initially tested against a panel of 15 clade B HIV-1 isolates, using a single concentration that is achievable in vivo (HIVIG, 2,500 microg/ml; MAbs, 25 microg/ml). Individual antibody reagents neutralized many of the viruses tested, but antibody potency varied substantially among the viruses. The virus neutralization produced by double combinations of HIVIG plus 2F5 or 2G12, the two MAbs together, or the triple combination of HIVIG, 2F5, and 2G12 was generally equal to or greater than that predicted by the effect of individual antibodies. Overall, the triple combination displayed the greatest magnitude and breadth of neutralization. Synergistic neutralization was evaluated by analyzing data from dose-response curves of each individual antibody reagent compared to the triple combination and was demonstrated against each of four viruses tested. Therefore, combinations of polyclonal and monoclonal anti-HIV antibodies can produce additive or synergistic neutralization of primary HIV-1 isolates. Passive immunotherapy for treatment or prophylaxis of HIV-1 should consider mixtures of potent neutralizing antibody reagents to expand the magnitude and breadth of virus neutralization.

  18. Potent and synergistic neutralization of human immunodeficiency virus (HIV) type 1 primary isolates by hyperimmune anti-HIV immunoglobulin combined with monoclonal antibodies 2F5 and 2G12.

    PubMed Central

    Mascola, J R; Louder, M K; VanCott, T C; Sapan, C V; Lambert, J S; Muenz, L R; Bunow, B; Birx, D L; Robb, M L

    1997-01-01

    Three antibody reagents that neutralize primary human immunodeficiency virus type 1 (HIV-1) isolates were tested for magnitude and breadth of neutralization when used alone or in double or triple combinations. Hyperimmune anti-HIV immunoglobulin (HIVIG) is derived from the plasma of HIV-1-infected donors, and monoclonal antibodies (MAbs) 2F5 and 2G12 bind to distinct regions of the HIV-1 envelope glycoprotein. The antibodies were initially tested against a panel of 15 clade B HIV-1 isolates, using a single concentration that is achievable in vivo (HIVIG, 2,500 microg/ml; MAbs, 25 microg/ml). Individual antibody reagents neutralized many of the viruses tested, but antibody potency varied substantially among the viruses. The virus neutralization produced by double combinations of HIVIG plus 2F5 or 2G12, the two MAbs together, or the triple combination of HIVIG, 2F5, and 2G12 was generally equal to or greater than that predicted by the effect of individual antibodies. Overall, the triple combination displayed the greatest magnitude and breadth of neutralization. Synergistic neutralization was evaluated by analyzing data from dose-response curves of each individual antibody reagent compared to the triple combination and was demonstrated against each of four viruses tested. Therefore, combinations of polyclonal and monoclonal anti-HIV antibodies can produce additive or synergistic neutralization of primary HIV-1 isolates. Passive immunotherapy for treatment or prophylaxis of HIV-1 should consider mixtures of potent neutralizing antibody reagents to expand the magnitude and breadth of virus neutralization. PMID:9311792

  19. Assembling different antennas of the gp120 high mannose-type glycans on gold nanoparticles provides superior binding to the anti-HIV antibody 2G12 than the individual antennas.

    PubMed

    Chiodo, Fabrizio; Enríquez-Navas, Pedro M; Angulo, Jesús; Marradi, Marco; Penadés, Soledad

    2015-03-20

    In order to re-build Man9GlcNAc2 clusters of the HIV gp120 glycoprotein, ∼2 nm gold glyconanoparticles (GNPs) were coated with the synthetic partial structures of Man9, the tetramannoside Manα1-2Manα1-2Manα1-3Manα1- and the pentamannoside Manα1-2Manα1-3[Manα1-2Manα1-6]Manα1-. Their interactions with the anti-HIV broadly neutralizing antibody 2G12 were studied by surface plasmon resonance (SPR)-based biosensors and saturation transfer difference (STD)-NMR spectroscopy. A synergistic effect of the tetra- and pentamannosides multimerized on a same GNP was observed. The assembly of these antennas of the gp120 high-mannose type glycan on GNPs provided superior binding to the anti-HIV antibody 2G12 with respect to GNPs carrying only the individual oligomannosides. The results presented in this work provide new molecular information on the interactions between clusters of oligomannosides and 2G12 that could help in the design of a carbohydrate-based vaccine against HIV.

  20. [Sensitivity of screening kits for anti-HIV antibodies. 1999 update. Retrovirus Working Group of the French Society for Blood Transfusion].

    PubMed

    Couroucé, A M

    1999-12-01

    A comparative evaluation of the sensitivity of anti-HIV screening assays has been recently performed with a selected panel of 65 samples which included HIV1 group M (per-seroconversions, seroconversions and seropositives infected with genotypes A, B, C, D, E), HIV1 group O and HIV2. The results obtained with the 21 ELISA HIV1 + HIV2 screening assays are presented. Among these 21 assays, four are combined anti-HIV and p24 Ag assays. All the assays except four fulfilled the criteria defined at the beginning of the study, i.e., positive results on all the seropositives including seroconversions and positive results on at least 50% of the per-seroconversions. The main differences were observed with the ten per-seroconversion samples, the number of positive results on such samples varying from three to ten. The constant improvement of anti-HIV screening tests which leads one to shorten the 'window' period permits and earlier diagnosis of HIV infection and a progressive decrease of the transfusional risk.

  1. Structural Analysis of the Glycosylated Intact HIV-1 gp120-b12 Antibody Complex Using Hydroxyl Radical Protein Footprinting.

    PubMed

    Li, Xiaoyan; Grant, Oliver C; Ito, Keigo; Wallace, Aaron; Wang, Shixia; Zhao, Peng; Wells, Lance; Lu, Shan; Woods, Robert J; Sharp, Joshua S

    2017-02-21

    Glycoprotein gp120 is a surface antigen and virulence factor of human immunodeficiency virus 1. Broadly neutralizing antibodies (bNAbs) that react to gp120 from a variety of HIV isolates offer hope for the development of broadly effective immunogens for vaccination purposes, if the interactions between gp120 and bNAbs can be understood. From a structural perspective, gp120 is a particularly difficult system because of its size, the presence of multiple flexible regions, and the large amount of glycosylation, all of which are important in gp120-bNAb interactions. Here, the interaction of full-length, glycosylated gp120 with bNAb b12 is probed using high-resolution hydroxyl radical protein footprinting (HR-HRPF) by fast photochemical oxidation of proteins. HR-HRPF allows for the measurement of changes in the average solvent accessible surface area of multiple amino acids without the need for measures that might alter the protein conformation, such as mutagenesis. HR-HRPF of the gp120-b12 complex coupled with computational modeling shows a novel extensive interaction of the V1/V2 domain, probably with the light chain of b12. Our data also reveal HR-HRPF protection in the C3 domain caused by interaction of the N330 glycan with the b12 light chain. In addition to providing information about the interactions of full-length, glycosylated gp120 with b12, this work serves as a template for the structural interrogation of full-length glycosylated gp120 with other bNAbs to better characterize the interactions that drive the broad specificity of the bNAb.

  2. Spontaneous secretion of immunoglobulins and anti-HIV-1 antibodies by in vivo activated B lymphocytes from HIV-1-infected subjects: monocyte and natural killer cell requirement for in vitro terminal differentiation into plasma cells.

    PubMed

    Fournier, Anne Marie; Fondere, Jean-Michel; Alix-Panabieres, Catherine; Merle, Corinne; Baillat, Vincent; Huguet, Marie-France; Taïb, Jacques; Ohayon, Viviane; Zembala, Marek; Reynes, Jacques; Vendrell, Jean Pierre

    2002-04-01

    Peripheral blood mononuclear cells from HIV-1-infected subjects secrete spontaneously in vitro immunoglobulins (Ig) and anti-HIV-1 antibodies (Ab). Purified B lymphocytes secrete only minute amounts of Ig and anti-HIV-1 Ab compared with unfractionated cells. Monocytes and natural killer cells enhanced both secretions by cell-to-cell contacts, involving adhesion and CD27, CD80 costimulatory molecules and IL-6. Cell interactions prolonged the survival and allowed the terminal maturation of in vivo activated B cells. The secreting cell precursors were highly differentiated B cells expressing a broad diversity of maturation markers (CD27(+), CD38(+), CD20(+/-), CD37(+/-), CD71(+/-), HLA-DQ(+/-), sIg(+/-)) but not sIgD, CD28, or CD40. This phenotype and the cytologic aspect of purified B cells suggest that these cells are early plasma cells originated from germinal center. Ex vivo secreting peripheral B cells had probably gone beyond the CD40/CD40 ligand interaction; then following CD28/CD80 and CD27/CD27 ligand (CD70) interactions in the presence of IL-6, they achieved in vitro their differentiation into plasma cells.

  3. Prolonged expression of an anti-HIV-1 gp120 minibody to the female rhesus macaque lower genital tract by AAV gene transfer.

    PubMed

    Abdel-Motal, U M; Harbison, C; Han, T; Pudney, J; Anderson, D J; Zhu, Q; Westmoreland, S; Marasco, W A

    2014-09-01

    Topical microbicides are a leading strategy for prevention of HIV mucosal infection to women; however, numerous pharmacokinetic limitations associated with coitally related dosing strategy have contributed to their limited success. Here we test the hypothesis that adeno-associated virus (AAV) mediated delivery of the b12 human anti-HIV-1 gp120 minibody gene to the lower genital tract of female rhesus macaques (Rh) can provide prolonged expression of b12 minibodies in the cervical-vaginal secretions. Gene transfer studies demonstrated that, of various green fluorescent protein (GFP)-expressing AAV serotypes, AAV-6 most efficiently transduced freshly immortalized and primary genital epithelial cells (PGECs) of female Rh in vitro. In addition, AAV-6-b12 minibody transduction of Rh PGECs led to inhibition of SHIV162p4 transmigration and virus infectivity in vitro. AAV-6-GFP could also successfully transduce vaginal epithelial cells of Rh when applied intravaginally, including p63+ epithelial stem cells. Moreover, intravaginal application of AAV-6-b12 to female Rh resulted in prolonged minibody detection in their vaginal secretions throughout the 79-day study period. These data provide proof of principle that AAV-6-mediated delivery of anti-HIV broadly neutralizing antibody (BnAb) genes to the lower genital tract of female Rh results in persistent minibody detection for several months. This strategy offers promise that an anti-HIV-1 genetic microbicide strategy may be possible in which topical application of AAV vector, with periodic reapplication as needed, may provide sustained local BnAb expression and protection.

  4. Evaluation of serum vitamin B12 levels and its correlation with anti-thyroperoxidase antibody in patients with autoimmune thyroid disorders.

    PubMed

    Jaya Kumari, S; Bantwal, Ganapathy; Devanath, Anitha; Aiyyar, Vageesh; Patil, Madhuri

    2015-04-01

    Vitamin B12 deficiency has been reported in patients with Autoimmune thyroid disorders. However there is limited data on exact prevalence of low B12 and its correlation with anti-thyroperoxidase antibody (anti-TPO) levels in these patients. The aim of our study was to estimate serum vitamin B12 levels in autoimmune thyroid disorders and to correlate B12 levels with anti-TPO. 350 patients were selected by convenient sampling. Vitamin B12 levels and thyroid parameters were estimated using fully automated chemiluminescence method on Access 2. Results of our study shows that using the manufacturer's cut-off of 145 pg/mL, the prevalence of low serum vitamin B12 was found to be 45.50 %. Higher prevalence (55 %) was seen based on the published cut-off of 200 pg/mL The study however did not demonstrate any significant correlation between vitamin B12 levels and anti-TPO (r = -0.11 and p value of 0.30).

  5. Polymeric anti-HIV therapeutics.

    PubMed

    Danial, Maarten; Klok, Harm-Anton

    2015-01-01

    The scope of this review is to highlight the application of polymer therapeutics in an effort to curb the transmission and infection of the human immunodeficiency virus (HIV). Following a description of the HIV life cycle, the use of approved antiretroviral drugs that inhibit critical steps in the HIV infection process is highlighted. After that, a comprehensive overview of the structure and inhibitory properties of polymeric anti-HIV therapeutic agents is presented. This overview will include inhibitors based on polysaccharides, synthetic polymers, dendritic polymers, polymer conjugates as well as polymeric DC-SIGN antagonists. The review will conclude with a section that discusses the applications of polymers and polymer conjugates as systemic and topical anti-HIV therapeutics.

  6. Structural Analysis of the Glycosylated Intact HIV-1 gp120–b12 Antibody Complex Using Hydroxyl Radical Protein Footprinting

    PubMed Central

    2017-01-01

    Glycoprotein gp120 is a surface antigen and virulence factor of human immunodeficiency virus 1. Broadly neutralizing antibodies (bNAbs) that react to gp120 from a variety of HIV isolates offer hope for the development of broadly effective immunogens for vaccination purposes, if the interactions between gp120 and bNAbs can be understood. From a structural perspective, gp120 is a particularly difficult system because of its size, the presence of multiple flexible regions, and the large amount of glycosylation, all of which are important in gp120–bNAb interactions. Here, the interaction of full-length, glycosylated gp120 with bNAb b12 is probed using high-resolution hydroxyl radical protein footprinting (HR-HRPF) by fast photochemical oxidation of proteins. HR-HRPF allows for the measurement of changes in the average solvent accessible surface area of multiple amino acids without the need for measures that might alter the protein conformation, such as mutagenesis. HR-HRPF of the gp120–b12 complex coupled with computational modeling shows a novel extensive interaction of the V1/V2 domain, probably with the light chain of b12. Our data also reveal HR-HRPF protection in the C3 domain caused by interaction of the N330 glycan with the b12 light chain. In addition to providing information about the interactions of full-length, glycosylated gp120 with b12, this work serves as a template for the structural interrogation of full-length glycosylated gp120 with other bNAbs to better characterize the interactions that drive the broad specificity of the bNAb. PMID:28102671

  7. MABGEL 1: First Phase 1 Trial of the Anti-HIV-1 Monoclonal Antibodies 2F5, 4E10 and 2G12 as a Vaginal Microbicide

    PubMed Central

    Morris, Georgina C.; Wiggins, Rebecca C.; Woodhall, Sarah C.; Bland, J. Martin; Taylor, Carol R.; Jespers, Vicky; Vcelar, Brigitta A.; Lacey, Charles J.

    2014-01-01

    Background Monoclonal antibodies (mAbs) which potently neutralize a broad range of HIV isolates are potential microbicide candidates. To date, topical application of mAbs in humans and their stability in vaginal secretions has not been studied. Objectives To assess the pharmacokinetics and safety of the mAbs 2F5, 4E10 and 2G12 when applied vaginally in women. Design A randomized, double-blind, placebo-controlled phase 1 trial. Methods Twenty-eight healthy, sexually abstinent women administered 2.5 g of gel daily for 12 days containing either 10 or 20 mg/g of each mAb (MABGEL) or placebo. Main clinical evaluations and sampling occurred at baseline, 1, 8, and 24 hours post-1st dose and 12 and 36 hours post-12th dose. Results After adjustment for dilution factors, median levels of 2F5, 4E10 and 2G12 in vaginal secretions at 1 hour post high-dose MABGEL were 7.74, 5.28 and 7.48 mg/ml respectively. Levels of 2F5 and 4E10 declined exponentially thereafter with similar estimated half-lives (4.6 and 4.3 hours). In contrast, 2G12 levels declined more rapidly in the first 8 hours, with an estimated half-life of 1.4 hours during this period. There was no evidence of systemic absorption. There were no significant differences in local or systemic adverse event rates or vaginal flora changes (by qPCR) between active and placebo gel arms. Whilst at least 1 adverse event was recorded in 96% of participants, 95% were mild and none were serious. Conclusions Vaginal application of 50 mg of each mAb daily was safe over a 12 day period. Median mAb concentrations detected at 8 hours post dose were potentially sufficient to block HIV transmission.2G12 exhibited more rapid elimination from the human vagina than 4E10 and 2F5, likely due to poor stability of 2G12 in acidic human vaginal secretions. Further research is needed to develop mAb-based vaginal microbicides and delivery systems. Trial Registration ISRCTN 64808733 UK CRN Portfolio 6470 PMID:25546420

  8. Vitamin B-12

    MedlinePlus

    ... Wellness Food and Nutrition Nutrients and Nutritional Info Vitamin B12 Vitamin B12 Food and NutritionNutrients and Nutritional InfoPrevention and Wellness Share Vitamin B12 Vitamin B12 is an important nutrient for ...

  9. Lectins with anti-HIV activity: a review.

    PubMed

    Akkouh, Ouafae; Ng, Tzi Bun; Singh, Senjam Sunil; Yin, Cuiming; Dan, Xiuli; Chan, Yau Sang; Pan, Wenliang; Cheung, Randy Chi Fai

    2015-01-06

    Lectins including flowering plant lectins, algal lectins, cyanobacterial lectins, actinomycete lectin, worm lectins, and the nonpeptidic lectin mimics pradimicins and benanomicins, exhibit anti-HIV activity. The anti-HIV plant lectins include Artocarpus heterophyllus (jacalin) lectin, concanavalin A, Galanthus nivalis (snowdrop) agglutinin-related lectins, Musa acuminata (banana) lectin, Myrianthus holstii lectin, Narcissus pseudonarcissus lectin, and Urtica diocia agglutinin. The anti-HIV algal lectins comprise Boodlea coacta lectin, Griffithsin, Oscillatoria agardhii agglutinin. The anti-HIV cyanobacterial lectins are cyanovirin-N, scytovirin, Microcystis viridis lectin, and microvirin. Actinohivin is an anti-HIV actinomycete lectin. The anti-HIV worm lectins include Chaetopterus variopedatus polychaete marine worm lectin, Serpula vermicularis sea worm lectin, and C-type lectin Mermaid from nematode (Laxus oneistus). The anti-HIV nonpeptidic lectin mimics comprise pradimicins and benanomicins. Their anti-HIV mechanisms are discussed.

  10. Three amino acid residues in the envelope of human immunodeficiency virus type 1 CRF07_BC regulate viral neutralization susceptibility to the human monoclonal neutralizing antibody IgG1b12.

    PubMed

    Nie, Jianhui; Zhao, Juan; Chen, Qingqing; Huang, Weijin; Wang, Youchun

    2014-10-01

    The CD4 binding site (CD4bs) of envelope glycoprotein (Env) is an important conserved target for anti-human immunodeficiency virus type 1 (HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12 (b12) could recognize conformational epitopes that overlap the CD4bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4bs epitopes.

  11. Vitamin B12 level

    MedlinePlus

    ... pg/mL are a possible sign of a vitamin B12 deficiency. People with this deficiency are likely to have ... level indicates a true B12 deficiency. Causes of vitamin B12 deficiency include: Not enough vitamin B12 in diet (rare, ...

  12. B cells from knock-in mice expressing broadly neutralizing HIV antibody b12 carry an innocuous B cell receptor responsive to HIV vaccine candidates.

    PubMed

    Ota, Takayuki; Doyle-Cooper, Colleen; Cooper, Anthony B; Doores, Katherine J; Aoki-Ota, Miyo; Le, Khoa; Schief, William R; Wyatt, Richard T; Burton, Dennis R; Nemazee, David

    2013-09-15

    Broadly neutralizing Abs against HIV protect from infection, but their routine elicitation by vaccination has not been achieved. To generate small animal models to test vaccine candidates, we have generated targeted transgenic ("knock-in") mice expressing, in the physiological Ig H and L chain loci, two well-studied broadly neutralizing Abs: 4E10, which interacts with the membrane proximal external region of gp41, and b12, which binds to the CD4 binding site on gp120. 4E10HL mice are described in the companion article (Doyle-Cooper et al., J. Immunol. 191: 3186-3191). In this article, we describe b12 mice. B cells in b12HL mice, in contrast to the case in 4E10 mice, were abundant and essentially monoclonal, retaining the b12 specificity. In cell culture, b12HL B cells responded avidly to HIV envelope gp140 trimers and to BCR ligands. Upon transfer to wild-type recipients, b12HL B cells responded robustly to vaccination with gp140 trimers. Vaccinated b12H mice, although generating abundant precursors and Abs with affinity for Env, were unable to rapidly generate neutralizing Abs, highlighting the importance of developing Ag forms that better focus responses to neutralizing epitopes. The b12HL and b12H mice should be useful in optimizing HIV vaccine candidates to elicit a neutralizing response while avoiding nonprotective specificities.

  13. Potential Anti-HIV Agents from Marine Resources: An Overview

    PubMed Central

    Vo, Thanh-Sang; Kim, Se-Kwon

    2010-01-01

    Human immunodeficiency virus (HIV) infection causes acquired immune deficiency syndrome (AIDS) and is a global public health issue. Anti-HIV therapy involving chemical drugs has improved the life quality of HIV/AIDS patients. However, emergence of HIV drug resistance, side effects and the necessity for long-term anti-HIV treatment are the main reasons for failure of anti-HIV therapy. Therefore, it is essential to isolate novel anti-HIV therapeutics from natural resources. Recently, a great deal of interest has been expressed regarding marine-derived anti-HIV agents such as phlorotannins, sulfated chitooligosaccharides, sulfated polysaccharides, lectins and bioactive peptides. This contribution presents an overview of anti-HIV therapeutics derived from marine resources and their potential application in HIV therapy. PMID:21339954

  14. Vitamin B-12

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin B-12 is a cofactor for 2 enzymes. In the cytoplasm, methionine synthase requires vitamin B-12 in the form of methylcobalamin and catalyzes the conversion of homocysteine to methionine by transfer of a methyl group from methyltetrahydrofolate.This enzyme links the methylation pathway through ...

  15. Evaluation of needle exchange in central London: behaviour change and anti-HIV status over one year.

    PubMed

    Hart, G J; Carvell, A L; Woodward, N; Johnson, A M; Williams, P; Parry, J V

    1989-05-01

    From November 1987 to October 1988, numbers of clients, visits made and syringes dispensed and returned were monitored at the needle exchange of the Middlesex Hospital, London, UK. A sample of clients were interviewed 1 month after entry to the scheme and again 3 months later to evaluate changes in injecting and sexual risk behaviours for HIV infection. Clients were asked to donate saliva for anti-HIV immunoglobulin G (IgG) antibody capture radioimmunoassay (GACRIA). The rate of lending and borrowing used injecting equipment fell, both compared with rates prior to entry to the scheme and during the period of study. Frequency of injecting did not increase and there was reduced incidence of abscesses. There was a highly significant correlation between multiple sexual partners and condom use and a reduction in the proportion of clients with multiple partners. On entry to the study, seven out of 121 (6%) clients were anti-HIV positive; after 3 months, a further two clients tested were found to be anti-HIV positive. Anti-HIV positivity prevalence for the year of study was nine out of 121 (7%). The scheme attracts clients, reduces injecting-related risk for HIV infection and has high equipment return rates. Saliva testing is acceptable to clients. Continued monitoring of anti-HIV in saliva is indicated.

  16. Anti-HIV activity of some synthetic lignanolides and intermediates.

    PubMed

    Sancho, Rocío; Medarde, Manuel; Sánchez-Palomino, Sonsoles; Madrigal, Blanca M; Alcamí, José; Muñoz, Eduardo; San Feliciano, Arturo

    2004-09-06

    The evaluation of the anti-HIV-1 activity of synthetic lignanolides and their intermediates is reported. The antiviral activity was studied through luciferase-based assays targeting the HIV-1 promoter activation induced by either, the HIV-1 Tat protein or the cellular transcription factor NF-kappaB, both known as crucial factors in HIV-1 replication. Among the compounds tested, three of them 2, 4 and 13 were further analysed for their anti-HIV-1 activity by recombinant virus assays, showing a suitable profile for development of novel anti-HIV-1 drugs.

  17. Zinc coupling potentiates anti-HIV-1 activity of baicalin.

    PubMed

    Wang, Qian; Wang, Yu-Tian; Pu, Shao-Ping; Zheng, Yong-Tang

    2004-11-12

    Baicalin (BA) has been shown with anti-HIV-1 activity. Zinc is a nutrient element. The anti-HIV-1 activity of zinc complex of baicalin (BA-Zn) in vitro was studied and compared with the anti-HIV-1 activities between BA and BA-Zn in the present study. Our results suggested that BA-Zn has lower cytotoxicity and higher anti-HIV-1 activity compared with those of BA in vitro. The CC50s of BA-Zn and BA were 221.52 and 101.73 microM, respectively. The cytotoxicity of BA-Zn was about 1.2-fold lower than that of BA. The BA and BA-Zn inhibited HIV-1 induced syncytium formation, HIV-1 p24 antigen and HIV-1 RT production. The EC50s of BA-Zn on inhibiting HIV-1 induced syncytium formation (29.08 microM) and RT production (31.17 microM) were lower than those of BA (43.27 and 47.34 microM, respectively). BA-Zn was more effective than BA in inhibiting the activities of recombinant RT and HIV-1 entry into host cells. Zinc coupling enhanced the anti-HIV-1 activity of baicalin.

  18. Bioavailability of vitamin B12

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin B12 deficiency is common in people of all ages who consume a low intake of animal-source foods, including populations in developing countries. It is also prevalent among the elderly, even in wealthier countries, due to their malabsorption of B12 from food. Several methods have been applied t...

  19. Vitamin B12 deficiency anemia

    MedlinePlus

    ... body tissues. There are many types of anemia. Vitamin B12 deficiency anemia is a low red blood cell count ... anemia often do well with treatment. Long-term vitamin B12 deficiency can cause nerve damage. This may be permanent ...

  20. Anti-HIV diphyllin glycosides from Justicia gendarussa.

    PubMed

    Zhang, Hong-Jie; Rumschlag-Booms, Emily; Guan, Yi-Fu; Liu, Kang-Lun; Wang, Dong-Ying; Li, Wan-Fei; Nguyen, Van Hung; Cuong, Nguyen Manh; Soejarto, Djaja Doel; Fong, Harry H S; Rong, Lijun

    2017-04-01

    In a search for new anti-HIV active leads from over several thousands of plant extracts, we have identified a potent plant lead. The active plant is determined as Justicia gendarussa (Acanthaceae), a medicinal plant that has been used for the treatment of injury, arthritis and rheumatism in Asia including China. Our bioassay-guided fractionation of the methanol extract of the stems and barks of the plant led to the isolation of two anti-HIV compounds, justiprocumins A and B. The compounds are identified as new arylnaphthalide lignans (ANL) glycosides. We further determined that the ANL glycosides are the chemical constituents that contribute to the anti-HIV activity of this plant. Justiprocumin B displayed potent activity against a broad spectrum of HIV strains with IC50 values in the range of 15-21 nM (AZT, IC50 77-95 nM). The compound also displayed potent inhibitory activity against the NRTI (nucleoside reverse transcriptase inhibitor)-resistant isolate (HIV-11617-1) of the analogue (AZT) as well as the NNRTI (non-nucleoside reverse transcriptase inhibitor)-resistant isolate (HIV-1N119) of the analogue (nevaripine).

  1. Synthetic galactomannans with potent anti-HIV activity.

    PubMed

    Budragchaa, Davaanyam; Bai, Shiming; Kanamoto, Taisei; Nakashima, Hideki; Han, Shuqin; Yoshida, Takashi

    2015-10-05

    Ring-opening polymerization of a new 1,6-anhydro disaccharide monomer, 1, 6-anhydro-2, 3-di-O-benzyl-4-O-(2', 3', 4', 6'-tetra-O-benzyl-α-d-galactopyranosyl)-α-d-mannopyranose, was carried out using PF5 as a catalyst under high vacuum at -60°C to give galactose branched mannopyranan (synthetic galactomannan), 4-O-α-d-galactopyranosyl-(1→6)-α-d-mannopyranan, after debenzylation with Na in liquid NH3. The ring-opening copolymerization with 1, 6-anhydro-tri-O-benzyl-α-d-mannopyranose in various feeds was also performed to give synthetic galactomannans with various proportions of galactose branches. After sulfation, sulfated synthetic galactomannans were found to have anti-HIV activity and cytotoxicity as high and low as those of standard curdlan and dextran sulfates, respectively, which are potent anti-HIV sulfated polysaccharides with low cytotoxicity. The anti-HIV mechanism of sulfated synthetic galactomannans used by poly-l-lysine as a model peptide of the HIV surface protein was estimated by using SPR, DSL, and zeta potential measurements, revealing the electrostatic interaction between negatively charged sulfate groups and positively charged amino groups.

  2. Oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency

    PubMed Central

    Vidal-Alaball, Josep; Butler, Christopher; Cannings-John, Rebecca; Goringe, Andrew; Hood, Kerry; McCaddon, Andrew; McDowell, Ian; Papaioannou, Alexandra

    2016-01-01

    Background Vitamin B12 deficiency is common and rises with age. Most people with vitamin B12 deficiency are treated in primary care with intramuscular vitamin B12 which is a considerable source of work for health care professionals. Several case control and case series studies have reported equal efficacy of oral administration of vitamin B12 but it is rarely prescribed in this form, other than in Sweden and Canada. Doctors may not be prescribing oral formulations because they are unaware of this option or have concerns regarding effectiveness. Objectives To assess the effectiveness of oral vitamin B12 versus intramuscular vitamin B12 for vitamin B12 deficiency. Search methods Searches were undertaken of The Cochrane Library, MEDLINE, EMBASE and Lilacs. The bibliographies of all relevant papers identified using this strategy were searched. In addition we contacted authors of relevant identified studies and Vitamin B12 research and pharmaceutical companies to enquire about other published or unpublished studies and ongoing trials. Selection criteria Randomised controlled trials (RCTs) examining the use of oral or intramuscular vitamin B12 to treat vitamin B12 deficiency. Data collection and analysis All abstracts or titles identified by the electronic searches were independently scrutinised by two reviewers. When a difference between reviewers arose, we obtained and reviewed a hard copy of the papers and made decisions by consensus. We obtained a copy of all preselected papers and two researchers independently extracted the data from these studies using piloted data extraction forms. The whole group checked whether inclusion and exclusion criteria were met, and disagreement was decided by consensus. The methodological quality of the included studies was independently assessed by two researchers and disagreements were brought back to the whole group and resolved by consensus. Main results Two RCT’s comparing oral with intramuscular administration of vitamin B12 met

  3. The rate of anti-HIV seropositivity among donated cadavers: experience in a cadaver donation center.

    PubMed

    Wiwanitkit, Viroj; Agthong, Sithiporn

    2002-01-01

    Cadavers are crucial for the medical education provided by medical schools. However, currently, donation is the only way to obtain cadavers for education in Thailand. Moreover, some traditional beliefs result in insufficient numbers of cadavers. Apart from finding donors, the occupational health of the workers in the cadaver donation center and the users, the medical students, residents, and staffs should be addressed. Screening for anti-HIV in donated organs is the current trend in transplantation medicine. Therefore, screening for anti-HIV in donated cadavers is useful. Here, we report the rate of anti-HIV seropositivity in cadavers in a 1-year period in our setting, the largest Thai Red Cross Society hospital. Of the total 84 cadavers received, two cadavers (2.4%) were anti-HIV seropositive. With the increasing rate of anti-HIV, screening for anti-HIV serology in donated cadavers for medical teaching is of great benefit.

  4. [Hemolytic anemias and vitamin B12 deficieny].

    PubMed

    Dietzfelbinger, Hermann; Hubmann, Max

    2015-08-01

    Hemolytic anemias consist of corpuscular, immun-hemolytic and toxic hemolytic anemias. Within the group of corpuscular hemolytic anemias, except for the paroxysmal nocturnal hemoglobinuria (PNH), all symptoms are caused by underlying heredetiary disorders within the red blood cell membran (hereditary spherocytosis), deficiencies of red cell enzymes (G6PDH- and pyrovatkinase deficiency) or disorders in the hemoglobin molecule (thalassaemia and sickle cell disease). Immune-hemolytic anemias are acquired hemolytic anemias and hemolysis is caused by auto- or allo-antibodies which are directed against red blood cell antigens. They are classified as warm, cold, mixed type or drug-induced hemolytic anemia. Therapy consists of glucocorticoids and other immunsuppressive drugs. Pernicious anemia is the most important vitamin B12 deficiency disorder. Diagnosis relies on cobalamin deficiency and antibodies to intrinsic factor. The management should focus on a possibly life-long replacement treatment with cobalamin.

  5. Cyclotriazadisulfonamides: promising new CD4-targeted anti-HIV drugs.

    PubMed

    Vermeire, Kurt; Schols, Dominique

    2005-08-01

    It is imperative to continue efforts to identify novel effective therapies that can assist in containing the spread of HIV. Recently acquired knowledge about the HIV entry process points to new strategies to block viral entry. For most HIV strains, the successful infection of their target cells is mainly dependent on the presence of the CD4 surface molecule, which serves as the primary virus receptor. The attachment of the viral envelope to this cellular CD4 receptor can be considered as an ideal target with multiple windows of opportunity for therapeutic intervention. Therefore, drugs that interfere with the CD4 receptor, and thus inhibit viral entry, may be promising agents for the treatment of AIDS. The CD4-targeted HIV entry inhibitors cyclotriazadisulfonamides represent a novel class of small molecule antiviral agents with a unique mode of action. The lead compound, CADA, specifically interacts with the cellular CD4 receptor and is active against a wide variety of HIV strains at submicromolar levels when evaluated in different cell-types such as T cells, monocytes and dendritic cells. Moreover, a strict correlation has been demonstrated between anti-HIV activity and CD4 interaction of about 20 different CADA analogues. In addition, CADA acted synergistically in combination with all other FDA-approved anti-HIV drugs as well as with compounds that target the main HIV co-receptors. In this article, the characteristics of cyclotriazadisulfonamide compounds are presented and the possible application of CADA as a microbicide is also discussed.

  6. Developments of indoles as anti-HIV-1 inhibitors.

    PubMed

    Xu, Hui; Lv, Min

    2009-01-01

    Since the first case of acquired immunodeficiency syndrome (AIDS) was reported in 1981, AIDS has always been a global health threat and the leading cause of deaths due to the rapid emergence of drug-resistance and unwanted metabolic side effects. Every day in 2007 an estimated 6850 people were newly infected with human immunodeficiency virus (HIV). Over the past 28 years the rapid worldwide spread of AIDS has prompted an intense research effort to discover compounds that could effectively inhibit HIV. The development of new, selective and safe inhibitors for the treatment of HIV, therefore, still remains a high priority for medical research. To the best of our knowledge, the indole derivatives have been considered as one class of promising HIV-1 inhibitors, such as delavirdine approved by the Food and Drug Administration (FDA) in 1997 for use in combination with other antiretrovirals in adults with HIV infection. In this review we focus on the synthesis and anti-HIV-1 activity of indole derivatives, in the meantime, the structure-activity relationship (SAR) for some derivatives are also surveyed. It will pave the way for the design of indole derivatives as anti-HIV-1 drugs in the future.

  7. Cross-neutralizing anti-HIV-1 human single chain variable fragments(scFvs) against CD4 binding site and N332 glycan identified from a recombinant phage library

    PubMed Central

    Khan, Lubina; Kumar, Rajesh; Thiruvengadam, Ramachandran; Parray, Hilal Ahmad; Makhdoomi, Muzamil Ashraf; Kumar, Sanjeev; Aggarwal, Heena; Mohata, Madhav; Hussain, Abdul Wahid; Das, Raksha; Varadarajan, Raghavan; Bhattacharya, Jayanta; Vajpayee, Madhu; Murugavel, K. G.; Solomon, Suniti; Sinha, Subrata; Luthra, Kalpana

    2017-01-01

    More than 50% of HIV-1 infection globally is caused by subtype_C viruses. Majority of the broadly neutralizing antibodies (bnAbs) targeting HIV-1 have been isolated from non-subtype_C infected donors. Mapping the epitope specificities of bnAbs provides useful information for vaccine design. Recombinant antibody technology enables generation of a large repertoire of monoclonals with diverse specificities. We constructed a phage recombinant single chain variable fragment (scFv) library with a diversity of 7.8 × 108 clones, using a novel strategy of pooling peripheral blood mononuclear cells (PBMCs) of six select HIV-1 chronically infected Indian donors whose plasma antibodies exhibited potent cross neutralization efficiency. The library was panned and screened by phage ELISA using trimeric recombinant proteins to identify viral envelope specific clones. Three scFv monoclonals D11, C11 and 1F6 selected from the library cross neutralized subtypes A, B and C viruses at concentrations ranging from 0.09 μg/mL to 100 μg/mL. The D11 and 1F6 scFvs competed with mAbs b12 and VRC01 demonstrating CD4bs specificity, while C11 demonstrated N332 specificity. This is the first study to identify cross neutralizing scFv monoclonals with CD4bs and N332 glycan specificities from India. Cross neutralizing anti-HIV-1 human scFv monoclonals can be potential candidates for passive immunotherapy and for guiding immunogen design. PMID:28332627

  8. The anti-HIV activities of photoactive terthiophenes.

    PubMed

    Hudson, J B; Harris, L; Marles, R J; Arnason, J T

    1993-08-01

    Various synthetic analogues of the naturally occurring terthiophene, alpha-terthienyl (alpha T), were evaluated for anti-human immunodeficiency virus (HIV) activity. The compounds were incubated individually with a known amount of the virus, with or without UVA radiation (long-wavelength ultraviolet) and residual virus was monitored for its ability to produce cytopathic effects in cell culture and the production of virus-specific protein (p24). The basic terthiophene structure was essential for good anti-HIV activity, although various side chains, such as alcohols, bromo, methyl, thiomethyl and trimethylsilyl groups, permitted retention of maximum activity. Under optimum conditions, as little as 12 ng/mL of these compounds (i.e. approximately 3 x 10(-8) M) could inactivate 10(3) infectious virions. None of the compounds however were more active than alpha T itself. In all cases, UVA radiation was essential. Several side chains decreased the antiviral efficacy, and some side chains abrogated the activity.

  9. Anti-HIV-1 activity of Trim 37.

    PubMed

    Tabah, Azah A; Tardif, Keith; Mansky, Louis M

    2014-04-01

    Trim 5α was the first member of the tripartite motif (TRIM) family of proteins that was identified to potently restrict human immunodeficiency virus type 1 (HIV-1) replication. The breadth of antiretroviral activity of TRIM family members is an active area of investigation. In this study, we demonstrate that human Trim 37 possesses anti-HIV-1 activity. This antiretroviral activity and the manner in which it was displayed were implicated by (1) decreased viral replication upon Trim 37 transient overexpression in virus-producing cells, (2) correlation of the reduction of viral infectivity with Trim 37 virion incorporation, (3) increased HIV-1 replication during siRNA depletion of Trim 37 expression, and (4) reduction in viral DNA synthesis upon Trim 37 transient overexpression. Our findings provide the first demonstration, to our knowledge, of the potent antiviral activity of human Trim 37, and implicate an antiviral mechanism whereby Trim 37 interferes with viral DNA synthesis.

  10. Therapeutic genes for anti-HIV/AIDS gene therapy.

    PubMed

    Bovolenta, Chiara; Porcellini, Simona; Alberici, Luca

    2013-01-01

    The multiple therapeutic approaches developed so far to cope HIV-1 infection, such as anti-retroviral drugs, germicides and several attempts of therapeutic vaccination have provided significant amelioration in terms of life-quality and survival rate of AIDS patients. Nevertheless, no approach has demonstrated efficacy in eradicating this lethal, if untreated, infection. The curative power of gene therapy has been proven for the treatment of monogenic immunodeficiensies, where permanent gene modification of host cells is sufficient to correct the defect for life-time. No doubt, a similar concept is not applicable for gene therapy of infectious immunodeficiensies as AIDS, where there is not a single gene to be corrected; rather engineered cells must gain immunotherapeutic or antiviral features to grant either short- or long-term efficacy mostly by acquisition of antiviral genes or payloads. Anti-HIV/AIDS gene therapy is one of the most promising strategy, although challenging, to eradicate HIV-1 infection. In fact, genetic modification of hematopoietic stem cells with one or multiple therapeutic genes is expected to originate blood cell progenies resistant to viral infection and thereby able to prevail on infected unprotected cells. Ultimately, protected cells will re-establish a functional immune system able to control HIV-1 replication. More than hundred gene therapy clinical trials against AIDS employing different viral vectors and transgenes have been approved or are currently ongoing worldwide. This review will overview anti-HIV-1 infection gene therapy field evaluating strength and weakness of the transgenes and payloads used in the past and of those potentially exploitable in the future.

  11. International award received recognizing anti-HIV spermicide.

    PubMed

    1998-10-19

    Until recently, the only topical microbicide being considered for protection against sexually transmitted HIV infection contains nonoxynol-9 (N-9), a detergent ingredient widely used for more than 30 years in the form of gels, foams, aerosols, creams, sponges, suppositories, films, and foaming tablets. While N-9 has both spermicidal and antibacterial/antiviral properties against pathogens responsible for STDs, including HIV, recent clinical studies have found it to be ineffective in protecting against HIV and other STDs. Moreover, N-9 disrupts cell membranes, damages cervicovaginal epithelia, and causes an acute tissue inflammatory response, thus enhancing the likelihood of HIV infection. There is therefore an urgent need for new, effective, safe, and easy-to-use microbicides with anti-HIV activity lacking detergent-type membrane toxicity. Dr. Osmond D'Cruz et al. of the Hughes Institute in St. Paul, Minnesota, have developed an anti-HIV spermicide with the potential of becoming the active ingredient in many beneficial products. Its lead compound is 400 times more potent than N-9 against HIV and at least 10 times more potent than N-9 as a spermicide. These dual-function compounds are non-inflammatory by their nature. Hughes et al.'s discovery is expected to enter human clinical trials within 12 months. A clinical paper describing their achievement won the prestigious Prize Paper Award for the Plenary Session of the Conjoint 16th World Congress on Fertility and Sterility at the 54th Annual Meeting of the American Society of Reproductive Medicine, held in San Francisco, California, during October 4-9, 1998.

  12. "Clickable" vitamin B12 derivative.

    PubMed

    Chromiński, Mikołaj; Gryko, Dorota

    2013-04-15

    A "clickable" vitamin B12 derivative possessing the azide functionality at the 5'-position was synthesized by means of a two-step procedure on the gram scale. The reaction of cobalamin with mesyl chloride (MsCl) afforded the 5'-OMs derivative, which was subsequently transformed to the desired 5'-azide, the structure of which was confirmed using X-ray analysis. It proved to be reactive in the azide-alkyne 1,3-dipolar cycloaddition reaction to give substituted triazoles in high yields. A study of the reaction conditions and the scope of the process are reported.

  13. Competitive immunoassay for analysis of vitamin B(12).

    PubMed

    Selva Kumar, L Sagaya; Thakur, M S

    2011-11-15

    In the current work, direct competitive enzyme-linked immunosorbent assay (ELISA) was developed for derivatized vitamin B(12) by generating chicken egg yolk immunoglobulins (IgY) against derivatized vitamin B(12) and purified using affinity chromatography. Checkerboard assay was performed with vitamin B(12) antibody and vitamin B(12)-alkaline phosphatase conjugate followed by its conjugate characterization using ultraviolet (UV) spectroscopy and high-performance liquid chromatography (HPLC). The limit of detection was 10 ng/ml with a linear working range of 10 to 10,000 ng/ml. The affinity constant (K(a)) of the vitamin B(12) antibody was found to be 4.23×10(8) L/mol. Cross-reactivity with other water-soluble vitamins was found to be less than 0.01% except for analogs of vitamin B(12) that showed 12% to 35%. The intra- and interassay coefficients of variation were found to be in the ranges from 0.0005% to 1.2% and 0.009% to 1.03%, respectively. The assay was validated with the HPLC method in terms of sensitivity, specificity, precision, and recovery of vitamin B(12) with spiked multivitamin injections, tablets, capsules, and chocolates. The HPLC method had a detection limit of 500 ng/ml with a linear working range of 1000 to 10,000 ng/ml. After extraction of vitamin B(12) using Amberlite XAD, the developed ELISA method correlated well with the established HPLC method with a correlation coefficient of 0.90.

  14. Anti-HIV-1 activities of extracts and phenolics from Smilax china L.

    PubMed

    Wang, Wei-Xin; Qian, Jing-Yi; Wang, Xiao-Jing; Jiang, Ai-Ping; Jia, Ai-Qun

    2014-01-01

    Four extracts (EtOH, CHCl3, EtOAc, and BuOH) and five phenolics (dihydrokaempferol (1), resveratrol (2), kaempferol-7-O-β-D-glucoside (3), dihydrokaempferol-3-O-α-L-rhamnoside (4), oxyresveratrol (5)) from Smilax china L. was evaluated for anti-HIV-1 activities and cytotoxicity activities in vitro. All these extracts and phenolics showed lower or no cytotoxicity at a concentration ranged from 0.8 μg/mL to 100 μg/mL, but some showed potential anti-HIV-1 activities, that is, BuOH extract and compound 2 showed higher anti-HIV-1 activities than other extracts and compounds in the tested concentrations. EtOAc extract and compound 1 and 3 showed moderate anti-HIV-1 activities at a concentration higher than 4 μg/mL. In the end, the structure-activity relationship of four extracts and five phenolics was discussed.

  15. Mechanisms and Modifications of Naturally Occurring Host Defense Peptides for Anti-HIV Microbicide Development

    PubMed Central

    Eade, Colleen R.; Wood, Matthew P.; Cole, Alexander M.

    2014-01-01

    Despite advances in the treatment of HIV infection, heterosexual transmission of HIV remains high, and vaccines to prevent HIV acquisition have been unfruitful. Vaginal microbicides, on the other hand, have demonstrated considerable potential for HIV prevention, and a variety of compounds have been screened for their activity and safety as anti-HIV microbicides. Among these are the naturally occurring host defense peptides, small peptides from diverse lineages with intrinsic antiviral activity. Naturally occurring host defense peptides with anti-HIV activity are promising candidates for vaginal microbicide development. Their structural variance and accompanying mechanistic diversity provide a wide range of inhibitors whose antiviral activity can be exerted at nearly every stage of the HIV lifecycle. Additionally, peptide modification has been explored as a method for improving the anti-HIV activity of host defense peptides. Structure- and sequence-based alterations have achieved varying success in improving the potency and specificity of anti-HIV peptides. Overall, peptides have been discovered or engineered to inhibit HIV with therapeutic indices of >1000, encouraging their advancement toward clinical trials. Here we review the naturally occurring anti-HIV host defense peptides, demonstrating their breadth of mechanistic diversity, and exploring approaches to enhance and optimize their activity in order to expedite their development as safe and effective anti-HIV vaginal microbicides. PMID:22264047

  16. Integrase Inhibitor Prodrugs: Approaches to Enhancing the Anti-HIV Activity of β-Diketo Acids.

    PubMed

    Nair, Vasu; Okello, Maurice

    2015-07-13

    HIV integrase, encoded at the 3'-end of the HIV pol gene, is essential for HIV replication. This enzyme catalyzes the incorporation of HIV DNA into human DNA, which represents the point of "no-return" in HIV infection. Integrase is a significant target in anti-HIV drug discovery. This review article focuses largely on the design of integrase inhibitors that are β-diketo acids constructed on pyridinone scaffolds. Methodologies for synthesis of these compounds are discussed. Integrase inhibition data for the strand transfer (ST) step are compared with in vitro anti-HIV data. The review also examines the issue of the lack of correlation between the ST enzymology data and anti-HIV assay results. Because this disconnect appeared to be a problem associated with permeability, prodrugs of these inhibitors were designed and synthesized. Prodrugs dramatically improved the anti-HIV activity data. For example, for compound, 96, the anti-HIV activity (EC50) improved from 500 nM for this diketo acid to 9 nM for its prodrug 116. In addition, there was excellent correlation between the IC50 and IC90 ST enzymology data for 96 (6 nM and 97 nM, respectively) and the EC50 and EC90 anti-HIV data for its prodrug 116 (9 nM and 94 nM, respectively). Finally, it was confirmed that the prodrug 116 was rapidly hydrolyzed in cells to the active compound 96.

  17. Vitamin B12 and Folate Test

    MedlinePlus

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Vitamin B12 and Folate Share this page: Was this ... as: Cobalamin; Folic Acid; RBC Folate Formal name: Vitamin B12; Folate Related tests: Complete Blood Count , Methylmalonic ...

  18. 7 CFR 15b.12 - Discrimination prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false Discrimination prohibited. 15b.12 Section 15b.12... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Employment Practices § 15b.12 Discrimination prohibited. (a... discrimination in employment under any program or activity receiving assistance from this Department. (2)...

  19. 7 CFR 15b.12 - Discrimination prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Discrimination prohibited. 15b.12 Section 15b.12... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Employment Practices § 15b.12 Discrimination prohibited. (a... discrimination in employment under any program or activity receiving assistance from this Department. (2)...

  20. 7 CFR 15b.12 - Discrimination prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Discrimination prohibited. 15b.12 Section 15b.12... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Employment Practices § 15b.12 Discrimination prohibited. (a... discrimination in employment under any program or activity receiving assistance from this Department. (2)...

  1. 7 CFR 15b.12 - Discrimination prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false Discrimination prohibited. 15b.12 Section 15b.12... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Employment Practices § 15b.12 Discrimination prohibited. (a... discrimination in employment under any program or activity receiving assistance from this Department. (2)...

  2. 18 CFR 1b.12 - Transcripts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Transcripts. 1b.12 Section 1b.12 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.12 Transcripts. Transcripts, if any,...

  3. 18 CFR 1b.12 - Transcripts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Transcripts. 1b.12 Section 1b.12 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.12 Transcripts. Transcripts, if any,...

  4. 34 CFR 5b.12 - Contractors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Contractors. 5b.12 Section 5b.12 Education Office of the Secretary, Department of Education PRIVACY ACT REGULATIONS § 5b.12 Contractors. (a) All contracts entered into on or after September 27, 1975 which require a contractor to maintain or on behalf of...

  5. 18 CFR 1b.12 - Transcripts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Transcripts. 1b.12 Section 1b.12 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.12 Transcripts. Transcripts, if any,...

  6. 18 CFR 1b.12 - Transcripts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Transcripts. 1b.12 Section 1b.12 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.12 Transcripts. Transcripts, if any,...

  7. 18 CFR 1b.12 - Transcripts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Transcripts. 1b.12 Section 1b.12 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.12 Transcripts. Transcripts, if any,...

  8. How common is vitamin B12 deficiency?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In considering the vitamin B-12 fortification of flour, it is important to know who is at risk of vitamin B-12 deficiency and whether those individuals would benefit from flour fortification.This article reviews current knowledge of the prevalence and causes of vitamin B-12 deficiency and considers ...

  9. 45 CFR 5b.12 - Contractors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Contractors. 5b.12 Section 5b.12 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PRIVACY ACT REGULATIONS § 5b.12 Contractors. (a) All contracts entered into on or after September 27, 1975 which require a contractor to maintain or on behalf of the Department to...

  10. 34 CFR 5b.12 - Contractors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Contractors. 5b.12 Section 5b.12 Education Office of the Secretary, Department of Education PRIVACY ACT REGULATIONS § 5b.12 Contractors. (a) All contracts entered into on or after September 27, 1975 which require a contractor to maintain or on behalf of...

  11. Vitamin B12 sources and bioavailability.

    PubMed

    Watanabe, Fumio

    2007-11-01

    The usual dietary sources of vitamin B(12) are animal foods, meat, milk, egg, fish, and shellfish. As the intrinsic factor-mediated intestinal absorption system is estimated to be saturated at about 1.5-2.0 microg per meal under physiologic conditions, vitamin B(12) bioavailability significantly decreases with increasing intake of vitamin B(12) per meal. The bioavailability of vitamin B(12) in healthy humans from fish meat, sheep meat, and chicken meat averaged 42%, 56%-89%, and 61%-66%, respectively. Vitamin B(12) in eggs seems to be poorly absorbed (< 9%) relative to other animal food products. In the Dietary Reference Intakes in the United States and Japan, it is assumed that 50% of dietary vitamin B(12) is absorbed by healthy adults with normal gastro-intestinal function. Some plant foods, dried green and purple lavers (nori) contain substantial amounts of vitamin B(12), although other edible algae contained none or only traces of vitamin B(12). Most of the edible blue-green algae (cyanobacteria) used for human supplements predominantly contain pseudovitamin B(12), which is inactive in humans. The edible cyanobacteria are not suitable for use as vitamin B(12) sources, especially in vegans. Fortified breakfast cereals are a particularly valuable source of vitamin B(12) for vegans and elderly people. Production of some vitamin B(12)-enriched vegetables is also being devised.

  12. Testing of viscous anti-HIV microbicides using Lactobacillus

    PubMed Central

    Moncla, B.J.; Pryke, K.; Rohan, L. C.; Yang, H.

    2012-01-01

    The development of topical microbicides for intravaginal use to prevent HIV infection requires that the drugs and formulated products be nontoxic to the endogenous vaginal Lactobacillus. In 30 min exposure tests we found dapivirine, tenofovir and UC781 (reverse transcriptase inhibitor anti-HIV drugs) as pure drugs or formulated as film or gel products were not deleterious to Lactobacillus species; however, PSC-RANTES (a synthetic CCR5 antagonist) killed 2 strains of Lactobacillus jensenii. To demonstrate the toxicity of formulated products a new assay was developed for use with viscous and non-viscous samples that we have termed the Lactobacillus toxicity test. We found that the vortex mixing of vaginal Lactobacillus species can lead to reductions in bacterial viability. Lactobacillus can survive brief, about 2 sec, but viability declines with increased vortex mixing. The addition of heat inactivated serum or bovine serum albumin, but not glycerol, prevented the decrease in bacterial viability. Bacillus atrophaeus spores also demonstrated loss of viability upon extended mixing. We observed that many of the excipients used in film formulation and the films themselves also afford protection from the killing during vortex mixing. This method is of relevance for toxicity for cidal activities of viscous products. PMID:22226641

  13. Differential in vitro anti-HIV activity of natural lignans.

    PubMed

    Schröder, H C; Merz, H; Steffen, R; Müller, W E; Sarin, P S; Trumm, S; Schulz, J; Eich, E

    1990-01-01

    Two naturally occurring lignanolides, isolated from the tropical climbing shrub Ipomoea cairica, (-)-arctigenin and (-)-trachelogenin, were found to inhibit strongly replication of human immunodeficiency virus type 1 (HIV-1; strain HTLV-III B) in vitro. At a concentration of 0.5 microM, (-)-arctigenin and (-)-trachelogenin inhibited the expression of HIV-1 proteins p17 and p24 by 80-90% and 60-70%, respectively. The reverse transcriptase activity in the culture fluids was reduced by 80-90% when the cells (HTLV-III B/H9) were cultivated in the presence of 0.5 microM (-)-arctigenin or 1 microM (-)-trachelogenin. At the same concentrations, the formation of syncytia in the HTLV-III B/H9-Jurkat cell system was inhibited by the compounds by more than 80%. A series of other lignan type compounds displayed no anti-HIV activity. Studying the molecular mechanism of action of (-)-arctigenin and (-)-trachelogenin we found that both compounds are efficient inhibitors of the nuclear matrix-associated DNA topoisomerase II activity, particularly of the enzyme from HIV-1-infected cells. Our results suggest that both compounds prevent the increase of topoisomerase II activity, involved in virus replication, after infection of cells with HIV-1.

  14. Combinatorial synthesis of anti-HIV agents--a review.

    PubMed

    Sriram, Dharmarajan; Yogeeswari, Perumal; Nagappa, Ananantha Naik

    2005-08-01

    Combinatorial chemistry has been well recognized as an important tool of drug discovery. An ongoing hand is to integrate the combinatorial approach with fundamentals of medicinal chemistry and rational drug design. The last five years has seen an explosion in the exploration and adoption of combinatorial techniques. Indeed, it is difficult to identify any other topic in chemistry that has ever caught the imagination of chemists with such fervor and with the continuous development of high throughput screening methods. There is a growing need for the synthesis of a large number of molecules. Compound libraries designed to produce specific inhibitors of therapeutic target proteins have generated significant interest in drug discovery research. Combinatorial chemistry provides the opportunity to generate large libraries of compounds for biological testing. A literature search revealed that many lead compounds have indeed been discovered from libraries and this review presents a survey of combinatorial synthesis of HIV-1 reverse transcriptase inhibitors, protease inhibitors, HIV-1 function inhibitors such as adsorption inhibitors, CCR5 antagonists and HIV-1 Tat-tar inhibitors that can be developed as potential anti-HIV drugs.

  15. Lentiviral vector engineering for anti-HIV RNAi gene therapy.

    PubMed

    ter Brake, Olivier; Westerink, Jan-Tinus; Berkhout, Ben

    2010-01-01

    RNA interference or RNAi-based gene therapy for the treatment of HIV-1 infection has recently emerged as a highly effective antiviral approach. The lentiviral vector system is a good candidate for the expression of antiviral short hairpin RNAs (shRNA) in HIV-susceptible cells. However, this strategy can give rise to vector problems because the anti-HIV shRNAs can also target the HIV-based lentiviral vector system. In addition, there may be self-targeting of the shRNA-encoding sequences within the vector RNA genome in the producer cell. The insertion of microRNA (miRNA) cassettes in the vector may introduce Drosha cleavage sites that will also result in the destruction of the vector genome during the production and/or the transduction process. Here, we describe possible solutions to these lentiviral-RNAi problems. We also describe a strategy for multiple shRNA expression to establish a combinatorial RNAi therapy.

  16. G-Quadruplex Forming Oligonucleotides as Anti-HIV Agents.

    PubMed

    Musumeci, Domenica; Riccardi, Claudia; Montesarchio, Daniela

    2015-09-22

    Though a variety of different non-canonical nucleic acids conformations have been recognized, G-quadruplex structures are probably the structural motifs most commonly found within known oligonucleotide-based aptamers. This could be ascribed to several factors, as their large conformational diversity, marked responsiveness of their folding/unfolding processes to external stimuli, high structural compactness and chemo-enzymatic and thermodynamic stability. A number of G-quadruplex-forming oligonucleotides having relevant in vitro anti-HIV activity have been discovered in the last two decades through either SELEX or rational design approaches. Improved aptamers have been obtained by chemical modifications of natural oligonucleotides, as terminal conjugations with large hydrophobic groups, replacement of phosphodiester linkages with phosphorothioate bonds or other surrogates, insertion of base-modified monomers, etc. In turn, detailed structural studies have elucidated the peculiar architectures adopted by many G-quadruplex-based aptamers and provided insight into their mechanism of action. An overview of the state-of-the-art knowledge of the relevance of putative G-quadruplex forming sequences within the viral genome and of the most studied G-quadruplex-forming aptamers, selectively targeting HIV proteins, is here presented.

  17. Rapid High-Level Production of Functional HIV Broadly Neutralizing Monoclonal Antibodies in Transient Plant Expression Systems

    PubMed Central

    Rosenberg, Yvonne; Sack, Markus; Montefiori, David; Forthal, Donald; Mao, Lingjun; -Abanto, Segundo Hernandez; Urban, Lori; Landucci, Gary; Fischer, Rainer; Jiang, Xiaoming

    2013-01-01

    Passive immunotherapy using anti-HIV broadly neutralizing monoclonal antibodies (mAbs) has shown promise as an HIV treatment, reducing mother-to-child-transmission (MTCT) of simian/human immunodeficiency virus (SHIV) in non-human primates and decreasing viral rebound in patients who ceased receiving anti-viral drugs. In addition, a cocktail of potent mAbs may be useful as mucosal microbicides and provide an effective therapy for post-exposure prophylaxis. However, even highly neutralizing HIV mAbs used today may lose their effectiveness if resistance occurs, requiring the rapid production of new or engineered mAbs on an ongoing basis in order to counteract the viral resistance or the spread of a certain HIV-1 clade in a particular region or patient. Plant-based expression systems are fast, inexpensive and scalable and are becoming increasingly popular for the production of proteins and monoclonal antibodies. In the present study, Agrobacterium-mediated transient transfection of plants, utilizing two species of Nicotiana, have been tested to rapidly produce high levels of an HIV 89.6PΔ140env and several well-studied anti-HIV neutralizing monoclonal antibodies (b12, 2G12, 2F5, 4E10, m43, VRC01) or a single chain antibody construct (m9), for evaluation in cell-based viral inhibition assays. The protein-A purified plant-derived antibodies were intact, efficiently bound HIV envelope, and were equivalent to, or in one case better than, their counterparts produced in mammalian CHO or HEK-293 cells in both neutralization and antibody dependent viral inhibition assays. These data indicate that transient plant-based transient expression systems are very adaptable and could rapidly generate high levels of newly identified functional recombinant HIV neutralizing antibodies when required. In addition, they warrant detailed cost-benefit analysis of prolonged incubation in plants to further increase mAb production. PMID:23533588

  18. The EGG 57-CO B-12 absorption test, in the evaluation of patients with low serum B-12

    SciTech Connect

    Sinow, R.M.; Carmel, R.; Siegel, M.E.

    1985-05-01

    The Schilling Test (ST) is the standard test for diagnosing vitamin B-12 malabsorption (MA). However, patients with subtle gastric dysfunction may have normal ST, but impaired absorption of B-12 given with food. The authors have adapted an Egg B-12 Absorption Test (EBAT) in which 57-Co cyanocobalamin (57-Co B-12) is mixed with scrambled egg to evaluate this phenomenon in patients with low serum B-12, normal ST and possible subtle MA. Lyophilized egg yolk is reconstituted and mixed with 57-Co- B-12 of equal dose to that of ST. The authors studied 46 individuals: 13 controls, 5 patients with known pernicious anemia (PA), in addition to 28 patients with low serum B-12 levels and normal ST. ST/EBAT ratios were calculated. Twenty-eight test patients excreted 13.3% on ST and 3.5% on EBAT. Mean ST/EBAT ratio was 8.2 (1.4-35.9). Five had EBAT results in the PA range (<1%) and ST/EBAT ratios (14.4-35.9) that were significantly elevated. This group is also evaluated with pepsinogen I/II ratios, gastric analysis, deoxyuridine suppression tests, anti intrinsic factor, and antiparietal cell antibodies. The authors' results indicate that the EBAT can differentiate between PA and non PA patients, and that some patients with low serum B-12 levels and normal ST may, in fact, have subtle MA. The EBAT, combined with ST/EBAT ratio, may provide a means for identifying this group of patients.

  19. Synthesis of 3' '-substituted TSAO derivatives with anti-HIV-1 and anti-HIV-2 activity through an efficient palladium-catalyzed cross-coupling approach.

    PubMed

    Lobatón, Esther; Rodríguez-Barrios, Fátima; Gago, Federico; Pérez-Pérez, María-Jesús; De Clercq, Erik; Balzarini, Jan; Camarasa, María-José; Velázquez, Sonsoles

    2002-08-29

    Various synthetic studies for the introduction of several functional groups at position 3' ' of the spiro moiety of TSAO derivatives have been explored. Among them, Stille cross-coupling of 3' '-iodo-TSAO derivatives with different stannanes provided an efficient and straightforward route for the direct and selective functionalization of the 3' '-position of the sultone spiro moiety via carbon-carbon bond formation. The compounds synthesized were evaluated for their inhibitory effect on HIV-1 and HIV-2 replication in cell culture. The introduction of a bromine and particularly an iodine at the 3' '-position conferred the highest anti-HIV-1 activity. In contrast, the presence at this position of (un)substituted vinyl, alkynyl, phenyl, or thienyl groups markedly diminished the anti-HIV-1 activity. Surprisingly, several of the 3' '-alkenyl-substituted TSAO derivatives also gained anti-HIV-2 activity at subtoxic concentrations, an observation that is very unusual for NNRTIs and never observed before for TSAO derivatives. Finally, the anti-HIV-1 activity of some of the 3' '-substituted TSAO derivatives is discussed in light of our recently proposed molecular model of interaction of TSAO derivatives with the interphase between the two subunits of HIV-1 reverse transcriptase.

  20. Laboratory assessment of vitamin B12 status.

    PubMed

    Harrington, Dominic J

    2017-02-01

    The detection and correction of vitamin B12 (B12) deficiency prevents megaloblastic anaemia and potentially irreversible neuropathy and neuropsychiatric changes. B12 status is commonly estimated using the abundance of the vitamin in serum, with ∼148 pmol/L (200 ng/L) typically set as the threshold for diagnosing deficiency. Serum B12 assays measure the sum of haptocorrin-bound and transcobalamin-bound (known as holotranscobalamin) B12 It is only holotranscobalamin that is taken up by cells to meet metabolic demand. Although receiver operator characteristic curves show holotranscobalamin measurement to be a moderately more reliable marker of B12 status than serum B12, both assays have an indeterminate range. Biochemical evidence of metabolic abnormalities consistent with B12 insufficiency is frequently detected despite an apparently sufficient abundance of the vitamin. Laboratory B12 status markers that reflect cellular utilisation rather than abundance are available. Two forms of B12 act as coenzymes for two different reactions. Methionine synthase requires methylcobalamin for the remethylation of methionine from homocysteine. A homocysteine concentration >20 µmol/L may suggest B12 deficiency in folate-replete patients. In the second B12-dependent reaction, methylmalonyl-CoA mutase uses adenosylcobalamin to convert methylmalonyl-CoA to succinyl-CoA. In B12 deficiency excess methylmalonyl-CoA is hydrolysed to methylmalonic acid. A serum concentration >280 nmol/L may suggest suboptimal status in young patients with normal renal function. No single laboratory marker is suitable for the assessment of B12 status in all patients. Sequential assay selection algorithms or the combination of multiple markers into a single diagnostic indicator are both approaches that can be used to mitigate inherent limitations of each marker when used independently.

  1. Vitamin B12 in health and disease.

    PubMed

    O'Leary, Fiona; Samman, Samir

    2010-03-01

    Vitamin B(12) is essential for DNA synthesis and for cellular energy production.This review aims to outline the metabolism of vitamin B(12), and to evaluate the causes and consequences of sub-clinical vitamin B(12) deficiency. Vitamin B(12) deficiency is common, mainly due to limited dietary intake of animal foods or malabsorption of the vitamin. Vegetarians are at risk of vitamin B(12) deficiency as are other groups with low intakes of animal foods or those with restrictive dietary patterns. Malabsorption of vitamin B(12) is most commonly seen in the elderly, secondary to gastric achlorhydria. The symptoms of sub-clinical deficiency are subtle and often not recognized. The long-term consequences of sub-clinical deficiency are not fully known but may include adverse effects on pregnancy outcomes, vascular, cognitive, bone and eye health.

  2. CD25 preselective anti-HIV vectors for improved HIV gene therapy.

    PubMed

    Kalomoiris, Stefanos; Lawson, Je'tai; Chen, Rachel X; Bauer, Gerhard; Nolta, Jan A; Anderson, Joseph S

    2012-12-01

    As HIV continues to be a global public health problem with no effective vaccine available, new and innovative therapies, including HIV gene therapies, need to be developed. Due to low transduction efficiencies that lead to low in vivo gene marking, therapeutically relevant efficacy of HIV gene therapy has been difficult to achieve in a clinical setting. Methods to improve the transplantation of enriched populations of anti-HIV vector-transduced cells may greatly increase the in vivo efficacy of HIV gene therapies. Here we describe the development of preselective anti-HIV lentiviral vectors that allow for the purification of vector-transduced cells to achieve an enriched population of HIV-resistant cells. A selectable protein, human CD25, not normally found on CD34+ hematopoietic progenitor cells (HPCs), was incorporated into a triple combination anti-HIV lentiviral vector. Upon purification of cells transduced with the preselective anti-HIV vector, safety was demonstrated in CD34+ HPCs and in HPC-derived macrophages in vitro. Upon challenge with HIV-1, improved efficacy was observed in purified preselective anti-HIV vector-transduced macrophages compared to unpurified cells. These proof-of-concept results highlight the potential use of this method to improve HIV stem cell gene therapy for future clinical applications.

  3. Anti-HIV cyclotides from the Chinese medicinal herb Viola yedoensis.

    PubMed

    Wang, Conan K L; Colgrave, Michelle L; Gustafson, Kirk R; Ireland, David C; Goransson, Ulf; Craik, David J

    2008-01-01

    Cyclotides are macrocyclic plant peptides characterized by a knotted arrangement of three disulfide bonds. They display a range of interesting bioactivities, including anti-HIV and insecticidal activities. More than 100 different cyclotides have been isolated from two phylogenetically distant plant families, the Rubiaceae and Violaceae. In this study we have characterized the cyclotides from Viola yedoensis, an important Chinese herb from the Violaceae family that has been reported to contain potential anti-HIV agents. From V. yedoensis five new and three known cyclotides were identified and shown to have anti-HIV activity. The most active of these is cycloviolacin Y5, which is one of the most potent of all cyclotides tested so far using in vitro XTT-based anti-HIV assays. Cycloviolacin Y5 is the most hydrophobic of the cyclotides from V. yedoensis. We show that there is a positive correlation between the hydrophobicity and the anti-HIV activity of the new cyclotides and that this trend tracks with their ability to disrupt membranes, as judged from hemolytic assays on human erythrocytes.

  4. Atypical B12 Deficiency with Nonresolving Paraesthesia

    PubMed Central

    Haider, S.; Ahmad, N.; Anaissie, E. J.; Abdel Karim, N.

    2013-01-01

    Vitamin B12 deficiency can present with various hematological, gastrointestinal and neurological manifestations. We report a case of elderly female who presented with neuropathy and vitamin B12 deficiency where the final work-up revealed polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS). This case suggests that, although POEMS syndrome is a rare entity, it can present with vitamin-B12 deficiency and thus specific work up for early diagnosis of POEMS should be considered in patients with B12 deficiency unresponsive to therapy. PMID:24349810

  5. Preparation and characterization of anti-HIV nanodrug targeted to microfold cell of gut-associated lymphoid tissue

    PubMed Central

    Roy, Upal; Ding, Hong; Pilakka-Kanthikeel, Sudheesh; Raymond, Andrea D; Atluri, Venkata; Yndart, Adriana; Kaftanovskaya, Elena M; Batrakova, Elena; Agudelo, Marisela; Nair, Madhavan

    2015-01-01

    The human immunodeficiency virus 1 (HIV-1) still remains one of the leading life-threatening diseases in the world. The introduction of highly active antiretroviral therapy has significantly reduced disease morbidity and mortality. However, most of the drugs have variable penetrance into viral reservoir sites, including gut-associated lymphoid tissue (GALT). Being the largest lymphoid organ, GALT plays a key role in early HIV infection and host–pathogen interaction. Many different treatment options have been proposed to eradicate the virus from GALT. However, it becomes difficult to deliver traditional drugs to the GALT because of its complex physiology. In this regard, we developed a polymer-based Pluronic nanocarrier containing anti-HIV drug called efavirenz (EFV) targeting Microfold cells (M-cells) in the GALT. M-cells are specialized epithelial cells that are predominantly present in the GALT. In this work, we have exploited this paracellular transport property of M-cells for targeted delivery of Pluronic nanocarrier tagged EFV, bioconjugated with anti-M-cell-specific antibodies to the GALT (nanodrug). Preliminary characterization showed that the nanodrug (EFV-F12-COOH) is of 140 nm size with 0.3 polydispersion index, and the zeta potential of the particles was −19.38±2.2 mV. Further, drug dissolution study has shown a significantly improved sustained release over free drugs. Binding potential of nanodrug with M-cell was also confirmed with fluorescence microscopy and in vitro uptake and release studies. The anti-HIV activity of the nanodrug was also significantly higher compared to that of free drug. This novel formulation was able to show sustained release of EFV and inhibit the HIV-1 infection in the GALT compared to the free drug. The present study has potential for our in vivo targeted nanodrug delivery system by combining traditional enteric-coated capsule technique via oral administration. PMID:26425084

  6. Antibody Gene Transfer for HIV Immunoprophylaxis

    PubMed Central

    Balazs, Alejandro B.; West, Anthony P.

    2015-01-01

    Antibody gene transfer, which involves the delivery of genes that encode potent, broadly neutralizing anti-HIV antibodies, is a promising new strategy to prevent HIV infection. A satellite symposium at the AIDS Vaccine 2012 conference brought together many of the groups working in this field. PMID:23238748

  7. Thiazoline Peptides and a Tris-Phenethyl Urea from Didemnum molle with Anti-HIV Activity

    PubMed Central

    Lu, Zhenyu; Harper, Mary Kay; Pond, Christopher D.; Barrows, Louis R.; Ireland, Chris M.; Wagoner, Ryan M. Van

    2012-01-01

    Summary As part of our screening for anti-HIV agents from marine invertebrates, the MeOH extract of Didemnum molle was tested and showed moderate in vitro anti-HIV activity. Bioassay-guided fractionation of a large scale extract allowed the identification of two new cyclopeptides, mollamides E and F (1 and 2), and one new tris-phenethyl urea, molleurea A (3). The absolute configurations were established using the advanced Marfey’s method. The three compounds were evaluated for anti-HIV activity in both an HIV integrase inhibition assay and a cytoprotective cell-based assay. Compound 2 was active in both assays with IC50 values of 39 and 78 µM, respectively. Compound 3 was only active in the cytoprotective cell-based assay with an IC50 value of 60 µM. PMID:22845329

  8. Thiazoline peptides and a tris-phenethyl urea from Didemnum molle with anti-HIV activity.

    PubMed

    Lu, Zhenyu; Harper, Mary Kay; Pond, Christopher D; Barrows, Louis R; Ireland, Chris M; Van Wagoner, Ryan M

    2012-08-24

    As part of our screening for anti-HIV agents from marine invertebrates, the MeOH extract of Didemnum molle was tested and showed moderate in vitro anti-HIV activity. Bioassay-guided fractionation of a large-scale extract allowed the identification of two new cyclopeptides, mollamides E and F (1 and 2), and one new tris-phenethyl urea, molleurea A (3). The absolute configurations were established using the advanced Marfey's method. The three compounds were evaluated for anti-HIV activity in both an HIV integrase inhibition assay and a cytoprotective cell-based assay. Compound 2 was active in both assays with IC(50) values of 39 and 78 μM, respectively. Compound 3 was active only in the cytoprotective cell-based assay, with an IC(50) value of 60 μM.

  9. Anti-HIV-1 activity of a tripodal receptor that recognizes mannose oligomers.

    PubMed

    Rivero-Buceta, Eva; Carrero, Paula; Casanova, Elena; Doyagüez, Elisa G; Madrona, Andrés; Quesada, Ernesto; Peréz-Pérez, María Jesús; Mateos, Raquel; Bravo, Laura; Mathys, Leen; Noppen, Sam; Kiselev, Evgeny; Marchand, Christophe; Pommier, Yves; Liekens, Sandra; Balzarini, Jan; Camarasa, María José; San-Félix, Ana

    2015-12-01

    The glycoprotein gp120 of the HIV-1 viral envelope has a high content in mannose residues, particularly α-1,2-mannose oligomers. Compounds that interact with these high-mannose type glycans may disturb the interaction between gp120 and its (co)receptors and are considered potential anti-HIV agents. Previously, we demonstrated that a tripodal receptor (1), with a central scaffold of 1,3,5-triethylbenzene substituted with three 2,3,4-trihydroxybenzoyl groups, selectively recognizes α-1,2-mannose polysaccharides. Here we present additional studies to determine the anti-HIV-1 activity and the mechanism of antiviral activity of this compound. Our studies indicate that 1 shows anti-HIV-1 activity in the low micromolar range and has pronounced gp120 binding and HIV-1 integrase inhibitory capacity. However, gp120 binding rather than integrase inhibition seems to be the primary mechanism of antiviral activity of 1.

  10. Fluorinated betulinic acid derivatives and evaluation of their anti-HIV activity

    PubMed Central

    Li, Jizhen; Goto, Masuo; Yang, Xiaoming; Morris-Natschke, Susan L.; Huang, Li; Chen, Chin-Ho

    2016-01-01

    Several fluorinated derivatives of the anti-HIV maturation agent bevirimat (1) were synthesized and evaluated for anti-HIV replication activity. The modified positions were the C-2, C-3, C-28, and C-30 positions, either directly on the betulinic acid (2) skeleton or in the attached side chains. Compound 18, which has a trifluoromethyl group added to C-30 of its isopropenyl group, exhibited similar potency to 1 against HIV-1NL4-3. In total, our current studies support our prior conclusion that C-30 allylic modification is unlikely to be a pharmacophore for anti-HIV activity, but could be a meaningful route to manipulate other properties of 2-related compounds. PMID:26598461

  11. In vitro anti-HIV-1 activity of fucoidan from Sargassum swartzii.

    PubMed

    Dinesh, Subramaniam; Menon, Thangam; Hanna, Luke E; Suresh, V; Sathuvan, M; Manikannan, M

    2016-01-01

    Sargassum swartzii, a marine brown algae with wide range of biological properties belongs to the family Sargassaceae. Bioactive fucoidan fractions (CFF, FF1 and FF2) were isolated from S. swartzii and characterized by linear gradient anion-exchange chromatography and FT-IR. The characterized fucoidan fractions contained mainly sugars, sulfate and uronic acid. In the present study, anti-HIV-1 property of the fucoidan fractions was investigated. Fraction FF2 was found to exhibit significant anti-HIV-1 activity at concentrations of 1.56 and 6.25 μg/ml as observed by >50% reduction in HIV-1 p24 antigen levels and reverse transcriptase activity. Fucoidan fractions have no cytotoxic effects on PBMCs at the concentration range of 1.56-1000 μg/ml. These results suggest that fucoidan fractions could have inhibitory activity against HIV and has potential as an anti-HIV-1 agent.

  12. Fluorinated betulinic acid derivatives and evaluation of their anti-HIV activity.

    PubMed

    Li, Jizhen; Goto, Masuo; Yang, Xiaoming; Morris-Natschke, Susan L; Huang, Li; Chen, Chin-Ho; Lee, Kuo-Hsiung

    2016-01-01

    Several fluorinated derivatives of the anti-HIV maturation agent bevirimat (1) were synthesized and evaluated for anti-HIV replication activity. The modified positions were the C-2, C-3, C-28, and C-30 positions, either directly on the betulinic acid (2) skeleton or in the attached side chains. Compound 18, which has a trifluoromethyl group added to C-30 of its isopropenyl group, exhibited similar potency to 1 against HIV-1NL4-3. In total, our current studies support our prior conclusion that C-30 allylic modification is unlikely to be a pharmacophore for anti-HIV activity, but could be a meaningful route to manipulate other properties of 2-related compounds.

  13. Stimuli-sensitive nanoparticles for multiple anti-HIV microbicides

    NASA Astrophysics Data System (ADS)

    Giri, Namita; Oh, Byeongtaek; Lee, Chi H.

    2016-05-01

    This study is aimed to develop and evaluate an advanced intravaginal formulation for the delivery of multiple anti-HIV microbicides. Novel stimuli-sensitive nanoparticles (NPs) which protected the encapsulated drugs from being degraded in acidic pH conditions were made of Eudragit S-100® (ES100®), a pH-sensitive polymer. ES100® NPs were prepared using the quasi-emulsion solvent diffusion technique and loaded with two microbicides namely Tenofovir (TNF) and Etravirine (ETV). The effects of various fabrication parameters on the formulation properties were evaluated for the optimization of ES100® NPs. The morphology of the ES100® NPs was examined by scanning electron microscopy. The cytotoxicity of NPs containing microbicides individually or in a combination was assessed using cell viability and trans-epithelial electrical resistance (TEER) measurements. The cellular uptake rates of the model microbicides by human vaginal epithelial cells, VK2 E6/E7 cells, were evaluated using confocal microscopy and florescence-assisted cell sorting technique. ES100® NPs had a spherical shape, smooth surface, and uniform texture with a little aggregation. The average particle size for NPs loaded with TNF ranged from 125 to 230 nm, whereas those for ETV-loaded NPs ranged from 160 to 280 nm. ES100® NPs had zeta potential in the range of -5 to -10 mV. In-vitro release studies displayed the potential benefits of ES100® NPs in retaining and protecting the loaded microbicides at vaginal pH (acidic), but immediately releasing them as the pH changes to neutral or 7.4 (physiological pH). Cell viability studies demonstrated that ES100® NPs did not exert any cytotoxicity individually or in a combination of both microbicides. TEER measurements confirmed that ES100® NPs loaded with TNF and ETV did not cause any changes in the barrier integrity of VK2 E6/E7 cell monolayer. The cellular uptake study revealed that ES100® NPs were taken by vaginal epithelial cells through the endocytosis

  14. Anti-HIV-1 Activity of Eight Monofloral Iranian Honey Types

    PubMed Central

    Behbahani, Mandana

    2014-01-01

    Monofloral Iranian honeys from eight floral sources were analyzed to determine their anti-HIV-1 activities as well as their effects on lymphocyte proliferation. The Peripheral Blood Mononuclear Cells (PBMCs) used in this study were prepared from five healthy volunteers who were seronegative for HIV, HCV, HBV and TB. The anti-HIV-1 activity of eight different honeys was performed by quantitative polymerase chain reaction (PCR) assay and high pure viral nucleic acid kit. The results demonstrated that monofloral honeys from Petro selinum sativum, Nigella sativa, Citrus sinensis, Zataria multiflora, Citrus aurantium and Zizyphus mauritiana flowers had potent anti-HIV-1 activity with half maximal effective concentration (EC50) values of 37.5, 88, 70, 88, 105 and 5 µg/ml respectively. However, monofloral Iranian honeys from Astragalus gummifer and Chamaemelum nobile flowers had weak anti-HIV-1 activity. The frequency and intensity of CD4 expression on PBMCs increased in the presence of all honey types. CD19 marker were also increased after the treatment with monofloral honeys from Z.multiflora and N. sativa. The anti-HIV-1 agent in monofloral honeys from P.sativum, N. sativa, Z. multiflora and Z. mauritiana flowers was detected by spectroscopic analysis as methylglyoxal. Time of drug addition studies demonstrated that the inhibitory effect of methylglyoxal is higher on the late stage of HIV-1 infection. The result demonstrated that methylglyoxal isolated from monofloral honey types is a good candidate for preclinical evaluation of anti-HIV-1 therapies. PMID:25333699

  15. Vitamin B-12 and Perinatal Health.

    PubMed

    Finkelstein, Julia L; Layden, Alexander J; Stover, Patrick J

    2015-09-01

    Vitamin B-12 deficiency (<148 pmol/L) is associated with adverse maternal and neonatal outcomes, including developmental anomalies, spontaneous abortions, preeclampsia, and low birth weight (<2500 g). The importance of adequate vitamin B-12 status periconceptionally and during pregnancy cannot be overemphasized, given its fundamental role in neural myelination, brain development, and growth. Infants born to vitamin B-12-deficient women may be at increased risk of neural tube closure defects, and maternal vitamin B-12 insufficiency (<200 pmol/L) can impair infant growth, psychomotor function, and brain development, which may be irreversible. However, the underlying causal mechanisms are unknown. This review was conducted to examine the evidence that links maternal vitamin B-12 status and perinatal outcomes. Despite the high prevalence of vitamin B-12 deficiency and associated risk of pregnancy complications, few prospective studies and, to our knowledge, only 1 randomized trial have examined the effects of vitamin B-12 supplementation during pregnancy. The role of vitamin B-12 in the etiology of adverse perinatal outcomes needs to be elucidated to inform public health interventions.

  16. Vitamin B-12 and Perinatal Health123

    PubMed Central

    Finkelstein, Julia L; Layden, Alexander J; Stover, Patrick J

    2015-01-01

    Vitamin B-12 deficiency (<148 pmol/L) is associated with adverse maternal and neonatal outcomes, including developmental anomalies, spontaneous abortions, preeclampsia, and low birth weight (<2500 g). The importance of adequate vitamin B-12 status periconceptionally and during pregnancy cannot be overemphasized, given its fundamental role in neural myelination, brain development, and growth. Infants born to vitamin B-12-deficient women may be at increased risk of neural tube closure defects, and maternal vitamin B-12 insufficiency (<200 pmol/L) can impair infant growth, psychomotor function, and brain development, which may be irreversible. However, the underlying causal mechanisms are unknown. This review was conducted to examine the evidence that links maternal vitamin B-12 status and perinatal outcomes. Despite the high prevalence of vitamin B-12 deficiency and associated risk of pregnancy complications, few prospective studies and, to our knowledge, only 1 randomized trial have examined the effects of vitamin B-12 supplementation during pregnancy. The role of vitamin B-12 in the etiology of adverse perinatal outcomes needs to be elucidated to inform public health interventions. PMID:26374177

  17. Malabsorption of protein bound vitamin B12.

    PubMed Central

    Dawson, D W; Sawers, A H; Sharma, R K

    1984-01-01

    Patients with subnormal serum vitamin B12 concentrations were tested for absorption of protein bound vitamin B12 and compared with controls. Absorption of the protein bound vitamin appeared to decrease with increasing age in healthy subjects. Differences between the result of this test and the result of the Schilling test in patients who had undergone gastric surgery were confirmed; such differences were also seen in some patients who had iron deficiency anaemia, an excessive alcohol intake, or folate deficiency. Defective absorption was also found in six patients with an adequate dietary intake of vitamin B12, normal Schilling test results, low serum vitamin concentrations, and tissue changes responding to treatment with vitamin B12. Malabsorption of the vitamin from protein bound sources, which is not detected by the Schilling test, may produce vitamin B12 deficiency of clinical importance. PMID:6421428

  18. New anti-HIV aptamers based on tetra-end-linked DNA G-quadruplexes: effect of the base sequence on anti-HIV activity.

    PubMed

    D'Atri, Valentina; Oliviero, Giorgia; Amato, Jussara; Borbone, Nicola; D'Errico, Stefano; Mayol, Luciano; Piccialli, Vincenzo; Haider, Shozeb; Hoorelbeke, Bart; Balzarini, Jan; Piccialli, Gennaro

    2012-10-04

    This communication reports on the synthesis and biophysical, biological and SAR studies of a small library of new anti-HIV aptamers based on the tetra-end-linked G-quadruplex structure. The new aptamers showed EC(50) values against HIV-1 in the range of 0.04-0.15 μM as well as affinities for the HIV-1 gp120 envelope in the same order of magnitude.

  19. Assay for vitamin B12 absorption and method of making labeled vitamin B12

    DOEpatents

    Anderson, Peter J [Davis, CA; Dueker, Stephen [Davis, CA; Miller, Joshua [Davis, CA; Green, Ralph [Elmacero, CA; Roth, John [Davis, CA; Carkeet, Colleen [Silver Spring, MD; Buchholz,; Bruce, A [Orinda, CA

    2012-06-19

    The invention provides methods for labeling vitamin B12 with .sup.14C, .sup.13C, tritium, and deuterium. When radioisotopes are used, the invention provides for methods of labeling B12 with high specific activity. The invention also provides labeled vitamin B12 compositions made in accordance with the invention.

  20. Semi-synthesis of oxygenated dolabellane diterpenes with highly in vitro anti-HIV-1 activity.

    PubMed

    Pardo-Vargas, Alonso; Ramos, Freddy A; Cirne-Santos, Claudio Cesar; Stephens, Paulo Roberto; Paixão, Izabel Christina Palmer; Teixeira, Valeria Laneuville; Castellanos, Leonardo

    2014-09-15

    Research on dolabellane diterpenes of brown algae Dictyota spp. has shown that these diterpenoids have strong anti-HIV-1 activity, but there are not data about antiviral activity of dolabellane diterpenes isolated from octocorals, which are antipodes of those isolated from the brown algae. Dolabellanes 13-keto-1(R),11(S)-dolabella-3(E),7(E),12(18)-triene (1) and β-Araneosene (2) were isolated from the Caribbean octocoral Eunicea laciniata, and both showed low anti-HIV-1 activity and low toxicity. Since it was shown that oxygenated dolabellanes from algae have better anti-HIV-1 activity, in this work some derivatives of the main dolabellane of E. laciniata1 were obtained by epoxidation (3), epoxide opening (4), and allylic oxidation (5). The derivatives showed significant improvement in the anti-HIV-1potency (100-fold), being compounds 3 and 5 the most active ones. Their high antiviral activities, along with their low cytotoxicity, make them promissory antiviral compounds; and it is worth noting that the absolute configuration at the ring junction in the dolabellane skeleton does not seem to be determinant in the antiviral potency of these diterpeneoids.

  1. Anti-HIV activities of natural antioxidant caffeic acid derivatives: toward an antiviral supplementation diet.

    PubMed

    Bailly, Fabrice; Cotelle, Philippe

    2005-01-01

    Since 1996, highly active antiretroviral therapy (HAART) was designed to rapidly control HIV replication. It has had a significant impact on patient health and progression of AIDS in developed countries, but its success has not been complete. HAART strategy still suffers from issues of patient compliance, cost, deleterious side effects and emerging drug resistance. Therefore, expansion of novel anti-HIV drugs and targets will be critical in the coming years. In this context, discovering anti-HIV agents from natural sources and particularly from plants, may highlight the principle of a nutritional antioxidant antiretroviral diet. In this paper, we review the putative anti-HIV activity of simple caffeic acid derivatives, together with their antioxidant properties. Toxicity, metabolism and bioavailability, when known, will also be detailed. Well-known caffeic acid derivatives, such as chicoric, rosmarinic and lithospermic acids, may be designed as future leads multi-target anti-HIV compounds and the plants and vegetables containing them as potent nutritional therapeutic supplementation source. They are not expected to replace the actual antiretroviral therapy, but more likely, to complete and perhaps lighten it by adapted diet.

  2. Plant-derived triterpenoids and analogues as antitumor and anti-HIV agents†

    PubMed Central

    Kuo, Reen-Yen; Qian, Keduo; Morris-Natschke, Susan L.; Lee, Kuo-Hsiung

    2013-01-01

    This article reviews the antitumor and anti-HIV activities of naturally occurring triterpenoids, including the lupane, ursane, oleanane, lanostane, dammarane, and miscellaneous scaffolds. Structure–activity relationships of selected natural compounds and their synthetic derivatives are also discussed. PMID:19779642

  3. Vitamin B-12 and Cognition in Children.

    PubMed

    Venkatramanan, Sudha; Armata, Ilianna E; Strupp, Barbara J; Finkelstein, Julia L

    2016-09-01

    Vitamin B-12 is essential for brain development, neural myelination, and cognitive function. Inadequate vitamin B-12 status during pregnancy and early childhood has been associated with adverse child health outcomes, including impaired cognitive development. However, the underlying mechanisms have not been elucidated. This review was conducted to examine the evidence that links vitamin B-12 and cognition in children. The search strategy resulted in 17 studies: 3 cross-sectional, 1 case-control, and 12 cohort studies, and 1 randomized trial. Cognitive processes assessed included attention, memory, and perception. Developmental outcomes, academic performance, and intelligence quotient were also considered. Despite the high prevalence of vitamin B-12 insufficiency and associated risk of adverse cognitive outcomes in children, to our knowledge, no studies to date have been conducted to examine the effects of vitamin B-12 supplementation on cognition in children. The role of vitamin B-12 in the etiology of child cognitive outcomes needs to be elucidated to inform public health interventions.

  4. An Effective Vaccination Approach Augments anti-HIV Systemic and Vaginal Immunity in Mice with Decreased HIV-1 Susceptible α4β7high CD4+ T Cells

    PubMed Central

    Zhu, Wei; Shi, Guoping; Tang, Haijun; Lewis, Dorothy E; Song, Xiao-Tong

    2013-01-01

    HIV-1 preferentially infects activated CD4+ T cells expressing α4β7 integrin and conventional vaccination approaches non-selectively induce immune responses including α4β7high CD4+ T cells, suggesting that current candidate AIDS vaccines may produce more target cells for HIV-1 and paradoxically enhance HIV-1 infection. Thus it remains a challenge to selectively induce robust anti-HIV immunity without the unwanted HIV-1 susceptible α4β7high CD4+ T cells. Here we describe a vaccination strategy that targets ALDH1a2, a retinoic acid producing enzyme in dendritic cells (DCs). Silencing ALDH1a2 in DCs enhanced the maturation and production of proinflammatory cytokines of DCs and promoted Th1/Th2 differentiation while suppressing Treg. ALDH1a2-silenced DCs effectively downregulated the expression of guthoming receptors α4β7 and CCR9 on activated T and B lymphocytes. Consequently, intranasal immunization of a lentiviral vaccine encoding ALDH1a2 shRNA and HIV-1 gp140 redirected gp140-specific mucosal T cell and antibody responses from the gut to the vaginal tract, while dramatically enhancing systemic gp140-specific immune responses. We further demonstrated that silencing ALDH1a2 in human DCs resulted in downregulation of β7 expression on activated autologous CD4+ T cells. Hence this study provides a unique and effective strategy to induce α4β7low anti-HIV immune responses. PMID:23157585

  5. An effective vaccination approach augments anti-HIV systemic and vaginal immunity in mice with decreased HIV-1 susceptible α4β7high CD4+ T cells.

    PubMed

    Zhu, Wei; Shi, Guoping; Tang, Haijun; Lewis, Dorothy E; Song, Xiao-Tong

    2013-01-01

    HIV-1 preferentially infects activated CD4(+) T cells expressing α4β7 integrin and conventional vaccination approaches non-selectively induce immune responses including α4β7(high) CD4(+) T cells, suggesting that current candidate AIDS vaccines may produce more target cells for HIV-1 and paradoxically enhance HIV-1 infection. Thus it remains a challenge to selectively induce robust anti-HIV immunity without the unwanted HIV-1 susceptible α4β77(high) CD4(+)+ T cells. Here we describe a vaccination strategy that targets ALDH1a2, a retinoic acid producing enzyme in dendritic cells (DCs). Silencing ALDH1a2 in DCs enhanced the maturation and production of proinflammatory cytokines of DCs and promoted Th1/Th2 differentiation while suppressing Treg. ALDH1a2-silenced DCs effectively downregulated the expression of guthoming receptors α4β77 and CCR9 on activated T and B lymphocytes. Consequently, intranasal immunization of a lentiviral vaccine encoding ALDH1a2 shRNA and HIV-1 gp140 redirected gp140-specific mucosal T cell and antibody responses from the gut to the vaginal tract, while dramatically enhancing systemic gp140-specific immune responses. We further demonstrated that silencing ALDH1a2 in human DCs resulted in downregulation of β7 expression on activated autologous CD4(+) T cells. Hence this study provides a unique and effective strategy to induce α4β7(low) anti-HIV immune responses.

  6. Crystal structure of a 3B3 variant - A broadly neutralizing HIV-1 scFv antibody

    SciTech Connect

    Clark, K. Reed; Walsh, Scott T.R.

    2009-12-10

    We present the crystal structure determination of an anti-HIV-1 gp120 single-chain variable fragment antibody variant, 3B3, at 2.5 {angstrom} resolution. This 3B3 variant was derived from the b12 antibody, using phage display and site-directed mutagenesis of the variable heavy chain (V{sub H}) complementary-determining regions (CDRs). 3B3 exhibits enhanced binding affinity and neutralization activity against several cross-clade primary isolates of HIV-1 by interaction with the recessed CD4-binding site on the gp120 envelope protein. Comparison with the structures of the unbound and bound forms of b12, the 3B3 structure closely resembles these structures with minimal differences with two notable exceptions. First, there is a reorientation of the CDR-H3 of the V{sub H} domain where the primary sequences evolved from b12 to 3B3. The structural changes in CDR-H3 of 3B3, in light of the b12-gp120 complex structure, allow for positioning an additional Trp side chain in the binding interface with gp120. Finally, the second region of structural change involves two peptide bond flips in CDR-L3 of the variable light (VL) domain triggered by a point mutation in CDR-H3 of Q100eY resulting in changes in the intramolecular hydrogen bonding patterning between the VL and VH domains. Thus, the enhanced binding affinities and neutralization capabilities of 3B3 relative to b12 probably result from higher hydrophobic driving potential by burying more aromatic residues at the 3B3-gp120 interface and by indirect stabilization of intramolecular contacts of the core framework residues between the VL and VH domains possibly through more favorable entropic effect through the expulsion of water.

  7. Optimized and enhanced DNA plasmid vector based in vivo construction of a neutralizing anti-HIV-1 envelope glycoprotein Fab.

    PubMed

    Muthumani, Kar; Flingai, Seleeke; Wise, Megan; Tingey, Colleen; Ugen, Kenneth E; Weiner, David B

    2013-10-01

    Monoclonal antibody preparations have demonstrated considerable clinical utility in the treatment of specific malignancies, as well as inflammatory and infectious diseases. Antibodies are conventionally delivered by passive administration, typically requiring costly large-scale laboratory development and production. Additional limitations include the necessity for repeat administrations, and the length of in vivo potency. Therefore, the development of methods to generate therapeutic antibodies and antibody like molecules in vivo, distinct from an active antigen-based immunization strategy, would have considerable clinical utility. In fact, adeno-associated viral (AAV) vector mediated delivery of immunoglobulin genes with subsequent generation of functional antibodies has recently been developed. As well, anon-viral vector mediated nucleic acid based delivery technology could permit the generation of therapeutic/prophylactic antibodies in vivo, obviating potential safety issues associated with viral vector based gene delivery. This delivery strategy has limitations as well, mainly due to very low in vivo production and expression of protein from the delivered gene. In the study reported here we have constructed an "enhanced and optimized" DNA plasmid technology to generate immunoglobulin heavy and light chains (i.e., Fab fragments) from an established neutralizing anti-HIV envelope glycoprotein monoclonal antibody (VRC01). This "enhanced" DNA (E-DNA) plasmid technology includes codon/RNA optimization, leader sequence utilization, as well as targeted potentiation of delivery and expression of the Fab immunoglobulin genes through use of "adaptive" in vivo electroporation. The results demonstrate that delivery by this method of a single administration of the optimized Fab expressing constructs resulted in generation of Fab molecules in mouse sera possessing high antigen specific binding and HIV neutralization activity for at least 7 d after injection, against diverse

  8. Dynamic behaviour of the B12 riboswitch

    NASA Astrophysics Data System (ADS)

    Santillán, Moisés; Mackey, Michael C.

    2005-03-01

    Riboswitches are RNA segments that serve as ligand-responsive genetic control elements. They modulate the expression of certain genes in response to changing concentrations of metabolites. In this paper, we study the dynamic behaviour of the B12 riboswitch in E. coli—perhaps the most widely studied and best known of all riboswitches—through a mathematical model of its regulatory pathway. To carry this out, we simulate dynamic experiments in which the bacterial B12 uptake capacity is measured after being depleted of this vitamin for a long time. The results of these simulations compare favourably with reported experimental data. The model also predicts that an overshoot of intracellular B12 should be observed if the replenishment experiments were to be carried out for longer times. This behaviour is discussed in terms of a possible evolutionary advantage for E. coli, together with the fact that regulation at the transcriptional and translational levels is almost equivalent dynamically.

  9. VirB12 is a serological marker of Brucella infection in experimental and natural hosts.

    PubMed

    Rolán, Hortensia G; den Hartigh, Andreas B; Kahl-McDonagh, Melissa; Ficht, Thomas; Adams, L Garry; Tsolis, Renée M

    2008-02-01

    The Brucella species type IV secretion system, encoded by the virB1-12 locus, is required for intracellular replication and persistent infection in vivo. The requirement of VirB proteins for infection suggests that they are expressed in vivo and may therefore represent serological markers of infection. To test this idea, we purified recombinant VirB1, VirB5, VirB11, and VirB12 and tested for their recognition by antibodies in sera from experimentally infected mice and goats by using an indirect enzyme-linked immunosorbent assay. Antibody responses to VirB12 but not to VirB1, VirB5, or VirB11 were detected in 20/20 mice experimentally inoculated with Brucella abortus and 12/12 goats experimentally infected with Brucella melitensis. The potential use of VirB12 as a serological tool for the diagnosis of brucellosis was evaluated in the natural bovine host. Serum samples from 145 cattle of known serology (29% negative and 71% positive) were analyzed for the production of antibody responses to VirB12. One hundred two cattle samples (70.3%) were positive for antibodies to VirB12, while 43 samples were negative (29.7%). A positive serological response to VirB12 correlated with positive serology to whole B. abortus antigen in 99% of samples tested. These results show that VirB12 is expressed during infection of both experimental and natural hosts of Brucella species, and they suggest that VirB12 may be a useful serodiagnostic marker for brucellosis.

  10. Folate, vitamin B12 and human health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the past decade the role of folate and vitamin B12 in human nutrition have been under constant re-examination. Basic knowledge on the metabolism and interactions between these essential nutrients has expanded and multiple complexities have been unraveled. These micronutrients have shared func...

  11. Rapid Conformational Epitope Mapping of anti-gp120 Antibodies with a Designed Mutant Panel Displayed on Yeast

    PubMed Central

    Mata-Fink, Jordi; Kriegsman, Barry; Xin, Yu Hui; Zhu, Hanna; Hanson, Melissa; Irvine, Darrell J.; Wittrup, K. Dane

    2013-01-01

    gp120 is a substrate for protein engineering both for HIV immunogen design and as a bait for isolating anti-HIV antibodies from patient samples. In this work we describe the display of a stripped core gp120 on the yeast cell surface. Validation against a panel of neutralizing antibodies confirms that yeast-displayed gp120 presents the CD4 binding site in the correct conformation. We map the epitope of the broadly neutralizing anti-gp120 antibody VRC01 using both a random mutagenesis library and a defined mutant panel, and find the resultant epitope maps are consistent with one another and with the crystallographically identified contact residues. Mapping the VRC01-competitive antibodies b12 and b13 reveals energetic differences in their epitopes that are not obvious from existing crystal structures. These data suggest mutation sets that abrogate binding to broadly neutralizing antibodies with greater specificity than the canonical mutation D368R, useful in rapidly assessing the nature of a vaccine response. PMID:23159556

  12. Anti-HIV-1 activity of propolis in CD4(+) lymphocyte and microglial cell cultures.

    PubMed

    Gekker, Genya; Hu, Shuxian; Spivak, Marla; Lokensgard, James R; Peterson, Phillip K

    2005-11-14

    An urgent need for additional agents to treat human immunodeficiency virus type 1 (HIV-1) infection led us to assess the anti-HIV-1 activity of the natural product propolis in CD4(+) lymphocytes and microglial cell cultures. Propolis inhibited viral expression in a concentration-dependent manner (maximal suppression of 85 and 98% was observed at 66.6 microg/ml propolis in CD4(+) and microglial cell cultures, respectively). Similar anti-HIV-1 activity was observed with propolis samples from several geographic regions. The mechanism of propolis antiviral property in CD4(+) lymphocytes appeared to involve, in part, inhibition of viral entry. While propolis had an additive antiviral effect on the reverse transcriptase inhibitor zidovudine, it had no noticeable effect on the protease inhibitor indinavir. The results of this in vitro study support the need for clinical trials of propolis or one or more of its components in the treatment of HIV-1 infection.

  13. [Anti-HIV chemical constituents of aerial parts of Caragana rosea].

    PubMed

    Yang, Guo-xun; Qi, Jian-bin; Cheng, Ke-jun; Hu, Chang-qi

    2007-02-01

    This study was intended to look for anti-HIV chemical constituents of aerial parts of Caragana rosea Turcz. Column chromatographic technique was used for the isolation and purification of constituents of Caragana rosea under the guide of anti-HIV assay. The structures were established on the basis of physical and chemical properties and spectroscopic data. Five compounds were obtained from the EtOAc fraction of aerial parts of Caragana rosea and identified as myricetin (1), mearnsetin (2), p-hydroxy cinnamic acid (3), cararosinol A (4) and cararosinol B (5). At the same time, one possible transformation route between cararosinol B and kobophenol A, another resveratrol tetramer isolated from this plant previously, was proposed. Compounds 4, 5 are new resveratrol tetramers, compounds 1 -3 were isolated from this plant for the first time. All compounds showed no activities in an in vitro assay against HIV-1.

  14. Triterpene Constituents of Euphorbia Erythradenia Bioss. and their Anti-HIV Activity

    PubMed Central

    Ayatollahi, Abdul Majid; Zarei, Seyed Mohammad; Memarnejadian, Arash; Ghanadian, Mustafa; Heydarian Moghadam, Mohammad; Kobarfard, Farzad

    2016-01-01

    Phytochemical investigation of the aerial parts of Euphorbia erythradenia Bioss. (Euphorbiaceae), one of Iranian endemic Euphorbias, with particular attention to triterpene constituents, using methanol solvent extraction was carried out. Five known triterpenes, including four cycloartanes and oleanolic acid, were isolated for the first time and identified using NMR and Mass techniques. Anti HIV activity of the isolated triterpenes and ingenoid diterpenes was evaluated using single cycle replicable HIV-1 (SCR HIV-1) virions. Molecular features of the most active compound (IC50 = 0.008 μM, CC50 = 3.264 μM, TI = 380.64), which showed higher therapeutic index than nevirapine, was assessed using molecular docking. Docking studies demonstrated three hydrogen bonds between HIV-1 virion protease active site and this compound with a distance less than 3 A° which can be responsible for the observed anti HIV-1 activity. PMID:28228800

  15. [Folate, vitamin B12 and human health].

    PubMed

    Brito, Alex; Hertrampf, Eva; Olivares, Manuel; Gaitán, Diego; Sánchez, Hugo; Allen, Lindsay H; Uauy, Ricardo

    2012-11-01

    During the past decade the role of folate and vitamin B12 in human nutrition have been under constant re-examination. Basic knowledge on the metabolism and interactions between these essential nutrients has expanded and multiple complexities have been unraveled. These micronutrients have shared functions and intertwined metabolic pathways that define the size of the "methyl donor" pool utilized in multiple metabolic pathways; these include DNA methylation and synthesis of nucleic acids. In Chile, folate deficiency is virtually nonexistent, while vitamin B12 deficiency affects approximately 8.5-51% depending on the cut-off value used to define deficiency. Folate is found naturally mainly in vegetables or added as folic acid to staple foods. Vitamin B12 in its natural form is present only in foods of animal origin, which is why deficit is more common among strict vegetarians and populations with a low intake of animal foods. Poor folate status in vulnerable women of childbearing age increases the risk of neural tube birth defects, so the critical time for the contribution of folic acid is several months before conception since neural tube closure occurs during the first weeks of life. The absorption of vitamin B12 from food is lower in older adults, who are considered to have higher risk of gastric mucosa atrophy, altered production of intrinsic factor and acid secretion. Deficiency of these vitamins is associated with hematological disorders. Vitamin B12 deficiency can also induce clinical and sub-clinical neurological and of other disorders. The purpose of this review is to provide an update on recent advances in the basic and applied knowledge of these vitamins relative to human health.

  16. Development of an implantable infusion pump for sustained anti-HIV drug administration.

    PubMed

    Baert, Lieven; Schueller, Laurent; Tardy, Yanik; Macbride, Doug; Klooster, Gerben van't; Borghys, Herman; Clessens, Ellen; Van Den Mooter, Guy; Van Gyseghem, Elke; Van Remoortere, Pieter; Wigerinck, Piet; Rosier, Jan

    2008-05-01

    Factors such as insufficient drug potency, non-compliance and restricted tissue penetration contribute to incomplete suppression of Human Immunodeficiency Virus (HIV) and the difficulty to control this infection. Infusion via standard catheters can be a source of infection, which is potentially life threatening in these patients. We developed an implantable infusion pump, allowing to accommodate large volumes (16-50mL) of high viscous solutions (up to 23.96mPas at 39 degrees C) of anti-HIV agents and providing sustained release of medication: a standard Codman 3000 pump, which was initially developed to release aqueous solutions ( approximately 0.7mPas) into the spinal cord such as for pain medication, was transformed for release of viscous solutions up to 40mPas by adapting the diameter of the capillary flow restrictor, the capillary length and way of catheterisation--by placing the indwelling catheter in the vena cava. A pilot study of the pump implanted in 2 dogs showed continuous steady-state release of the protease inhibitor darunavir (25mg/dog/day administered for 25 days), thereby achieving plasma concentration levels of approximately 40ng/mL. Steady-state plasma levels were reproducible after monthly refill of the pumps. In conclusion, the implantable adapted Codman 3000 constant-flow infusion pump customized to anti-HIV therapy allows sustained release of anti-HIV medication and may represent an opportunity to reduce the pill burden and complexity of dosing schemes associated with common anti-HIV therapy.

  17. Anti-HIV-1 Activity of a New Scorpion Venom Peptide Derivative Kn2-7

    PubMed Central

    Chen, Yaoqing; Cao, Luyang; Zhong, Maohua; Zhang, Yan; Han, Chen; Li, Qiaoli; Yang, Jingyi; Zhou, Dihan; Shi, Wei; He, Benxia; Liu, Fang; Yu, Jie; Sun, Ying; Cao, Yuan; Li, Yaoming; Li, Wenxin; Guo, Deying; Cao, Zhijian; Yan, Huimin

    2012-01-01

    For over 30 years, HIV/AIDS has wreaked havoc in the world. In the absence of an effective vaccine for HIV, development of new anti-HIV agents is urgently needed. We previously identified the antiviral activities of the scorpion-venom-peptide-derived mucroporin-M1 for three RNA viruses (measles viruses, SARS-CoV, and H5N1). In this investigation, a panel of scorpion venom peptides and their derivatives were designed and chosen for assessment of their anti-HIV activities. A new scorpion venom peptide derivative Kn2-7 was identified as the most potent anti-HIV-1 peptide by screening assays with an EC50 value of 2.76 µg/ml (1.65 µM) and showed low cytotoxicity to host cells with a selective index (SI) of 13.93. Kn2-7 could inhibit all members of a standard reference panel of HIV-1 subtype B pseudotyped virus (PV) with CCR5-tropic and CXCR4-tropic NL4-3 PV strain. Furthermore, it also inhibited a CXCR4-tropic replication-competent strain of HIV-1 subtype B virus. Binding assay of Kn2-7 to HIV-1 PV by Octet Red system suggested the anti-HIV-1 activity was correlated with a direct interaction between Kn2-7 and HIV-1 envelope. These results demonstrated that peptide Kn2-7 could inhibit HIV-1 by direct interaction with viral particle and may become a promising candidate compound for further development of microbicide against HIV-1. PMID:22536342

  18. Parthenium hysterophorus: A Probable Source of Anticancer, Antioxidant and Anti-HIV Agents

    PubMed Central

    Kumar, Shashank; Chashoo, Gousia; Saxena, Ajit K.; Pandey, Abhay K.

    2013-01-01

    The present work reports the anticancer, antioxidant, lipo-protective, and anti-HIV activities of phytoconstituents present in P. hysterophorus leaf. Dried leaf samples were sequentially extracted with nonpolar and polar solvents. Ethanol fraction showed noticeable cytotoxic activity (81–85%) in SRB assay against MCF-7 and THP-1 cancer cell lines at 100 μg/ml concentration, while lower activity was observed with DU-145 cell line. The same extract exhibited 17–98% growth inhibition of HL-60 cancer cell lines in MTT assay, showing concentration dependent response. Ethanol extract caused 12% reduction in mitochondrial membrane potential and 10% increment in sub G1 population of HL-60 cell lines. Several leaf fractions, namely, ethyl acetate, ethanol, and aqueous fractions exhibited considerable reducing capability at higher concentrations. Most of the extracts demonstrated appreciable (>75%) metal ion chelating and hydroxyl radical scavenging activities at 200 µg/ml. All the extracts except aqueous fraction accounted for about 70–80% inhibition of lipid peroxidation in rat liver homogenate indicating protective response against membrane damage. About 40% inhibition of reverse transcriptase (RT) activity was observed in hexane fraction in anti-HIV assay at 6.0 µg/ml concentration. The study showed that phytochemicals present in P. hysterophorus leaf have considerable potential as cytotoxic and antioxidant agents with low to moderate anti-HIV activity. PMID:24350290

  19. False-normal vitamin B12 results in a patient with pernicious anaemia.

    PubMed

    Wainwright, P; Narayanan, S; Cook, P

    2015-12-01

    Pernicious anaemia is a common autoimmune disorder with a prevalence of approximately 4% amongst Europeans. If untreated, it can result in permanent neurological disability or death. Central to the diagnosis is establishing the presence of vitamin B12 deficiency. Concern has been raised recently regarding false-normal results obtained with competitive-binding vitamin B12 assays performed on automated biochemistry platforms in patients with pernicious anaemia due to the presence of interfering anti-intrinsic factor antibodies in the patient sample. We report a case in which diagnosis of pernicious anaemia was delayed due to false-normal vitamin B12 results. Questioning the results in light of high pre-test probability, and knowledge of the role of functional markers of vitamin B12 deficiency enabled the correct diagnosis to be made so that effective treatment could be initiated. It is crucial that those who frequently request vitamin B12 are aware of the potential problems with the available assays and how these problems can be addressed. We suggest that all patients with normal vitamin B12 levels where there is a high clinical suspicion for deficiency such as a macrocytic anaemia, neurological symptoms or megaloblastic bone marrow should have a functional assay of vitamin B12 (plasma homocysteine or methylmalonic acid) checked to further investigate for vitamin B12 deficiency.

  20. The CD4 molecule, the human immunodeficiency virus and anti-idiotypic antibodies.

    PubMed

    Del Guercio, P; Zanetti, M

    1987-01-01

    The CD4 molecule is the cellular receptor for human immunodeficiency viruses (HIV). Administration of antibodies to the equivalent molecule in mice (L3T4) induces unresponsiveness to antigens given to or around the same time. Here Paolo del Guercio and Maurizio Zanetti suggest that in AIDS patients anti-idiotypic antibodies elicited to anti-HIV antibodies may bind to CD4 molecules, inducing unresponsiveness to viral and other antigens as anti-L3T4 antibodies do in mice. This possibility may hinder attempts to establish anti-HIV immunity by vaccination.

  1. Vitamin B-12 radioassay in the diagnosis of vitamin B-12 deficiency

    SciTech Connect

    Weir, G.J. Jr.

    1984-01-01

    It became apparent in 1978 that some radioassays for Vitamin B-12 were falsely normal. This investigation was performed to assure the accuracy of our assay. False normal B-12 levels may result in permanent damage or delay in relieving distressful symptoms. False low levels result in no permanent sequalae. ''Normal'' values should be set with these consequences in mind. The authors reviewed clinical charts on patients with <300 pg/m1 serum B-12 in 1000 consecutive determinations and all patients newly diagnosed B-12 deficient 1/1/83 to 10/14/83. Simu1TRAC Radioassay, Becton Dickinson Co., modified by correction for serum nonspecific binding is used. ''Normal'' values (234-1000 pg/m1) are based on 47 outpatients. 176 of the 1000 assays resulted in levels <300 pg/m1. 87 were from other location with no clinical information. 89 assays on Marshfield Clinic patients included 2 duplicates. 45 patients were newly diagnosed B-12 deficient 1/1/83 to 10/14/83. 12 were diagnosed elsewhere and on therapy. 32 had assays <234 pg/m1. 1 with normal B-12 is ''possibly deficient'', a Schilling test is scheduled. The authors conclude that their B-12 assay has correctly identified 32 clinically accepted B-12 deficient patients. 1 possibly deficient patient was normal. 25 of 42 patients with levels below normal are deficient. The false positive rate is felt acceptable in view of the false negative rate and the consequences of the respective errors.

  2. Antibody

    MedlinePlus

    An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples ... microorganisms (bacteria, fungi, parasites, and viruses) and chemicals. Antibodies may be produced when the immune system mistakenly ...

  3. 21 CFR 862.1810 - Vitamin B12 test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vitamin B12 test system. 862.1810 Section 862.1810....1810 Vitamin B12 test system. (a) Identification. A vitamin B12 test system is a device intended to measure vitamin B12 in serum, plasma, and urine. Measurements obtained by this device are used in...

  4. 21 CFR 862.1810 - Vitamin B 12 test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vitamin B 12 test system. 862.1810 Section 862....1810 Vitamin B 12 test system. (a) Identification. A vitamin B12 test system is a device intended to measure vitamin B12 in serum, plasma, and urine. Measurements obtained by this device are used in...

  5. 21 CFR 862.1810 - Vitamin B12 test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vitamin B12 test system. 862.1810 Section 862.1810....1810 Vitamin B12 test system. (a) Identification. A vitamin B12 test system is a device intended to measure vitamin B12 in serum, plasma, and urine. Measurements obtained by this device are used in...

  6. 21 CFR 862.1810 - Vitamin B 12 test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vitamin B 12 test system. 862.1810 Section 862....1810 Vitamin B 12 test system. (a) Identification. A vitamin B12 test system is a device intended to measure vitamin B12 in serum, plasma, and urine. Measurements obtained by this device are used in...

  7. 21 CFR 862.1810 - Vitamin B12 test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vitamin B12 test system. 862.1810 Section 862.1810....1810 Vitamin B12 test system. (a) Identification. A vitamin B12 test system is a device intended to measure vitamin B12 in serum, plasma, and urine. Measurements obtained by this device are used in...

  8. Antivitamins B12--A Structure- and Reactivity-Based Concept.

    PubMed

    Kräutler, Bernhard

    2015-08-03

    B12 -antimetabolites are compounds that counteract the physiological effects of vitamin B12 and related natural cobalamins. Presented here is a structure- and reactivity-based concept of the specific 'antivitamins B12 ': it refers to analogues of vitamin B12 that display high structural similarity to the vitamin and are 'locked chemically' to prevent their metabolic conversion into the crucial organometallic B12 -cofactors. Application of antivitamins B12 to healthy laboratory animals is, thus, expected to induce symptoms of B12 -deficiency. Antivitamins B12 may, hence, be helpful in elucidating still largely puzzling pathophysiological phenomena associated with B12 -deficiency, and also in recognizing physiological roles of B12 that probably still remain to be discovered.

  9. Hydroxytyrosol: a new class of microbicide displaying broad anti-HIV-1 activity

    PubMed Central

    Bedoya, Luis M.; Beltrán, Manuela; Obregón-Calderón, Patricia; García-Pérez, Javier; de la Torre, Humberto E.; González, Nuria; Pérez-Olmeda, Mayte; Auñón, David; Capa, Laura; Gómez-Acebo, Eduardo; Alcamí, José

    2016-01-01

    Objective: To investigate the toxicity and activity against HIV of 5-hydroxytyrosol as a potential microbicide. Design: The anti-HIV-1 activity of 5-hydroxytyrosol, a polyphenolic compound, was tested against wild-type HIV-1 and viral clones resistant to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors and integrase inhibitors. In addition to its activity against founder viruses, different viral subtypes and potential synergy with tenofovir disoproxil fumarate, lamivudine and emtricitabine was also tested. 5-Hydroxytyrosol toxicity was evaluated in vivo in rabbit vaginal mucosa. Methods: We have cloned pol gene from drug-resistant HIV-1 isolated from infected patients and env gene from Fiebeg III/IV patients or A, C, D, E, F and G subtypes in the NL4.3-Ren backbone. 5-Hydroxytyrosol anti-HIV-1 activity was evaluated in infections of MT-2, U87-CCR5 or peripheral blood mononuclear cells preactivated with phytohemagglutinin + interleukin-2 with viruses obtained through 293T transfections. Inhibitory concentration 50% and cytotoxic concentration 50% were calculated. Synergy was analysed according to Chou and Talalay method. In-vivo toxicity was evaluated for 14 days in rabbit vaginal mucosa. Results: 5-Hydroxytyrosol inhibited HIV-1 infections of recombinant or wild-type viruses in all the target cells tested. Moreover, 5-hydroxytyrosol showed similar inhibitory concentration 50% values for infections with NRTIs, NNRTIs, protease inhibitors and INIs resistant viruses; founder viruses and all the subtypes tested. Combination of 5-hydroxytyrosol with tenofovir was found to be synergistic, whereas it was additive with lamivudine and emtricitabine. In-vivo toxicity of 5-hydroxytyrosol was very low even at the highest tested doses. Conclusion: 5-Hydroxytyrosol displayed a broad anti-HIV-1 activity in different cells systems in the absent of in-vivo toxicity, therefore supporting its

  10. Synthesis and bioevaluation of substituted chalcones, coumaranones and other flavonoids as anti-HIV agents.

    PubMed

    Cole, Amy L; Hossain, Sandra; Cole, Alex M; Phanstiel, Otto

    2016-06-15

    A series of chalcone, flavone, coumaranone and other flavonoid compounds were screened for their anti HIV-1 activity in two cell culture models using TZM-bl and PM1 cells. Within the systems evaluated, the most promising compounds contained either an α- or β-hydroxy-carbonyl motif within their structure (e.g., 8 and 9). Efficacious substituents were identified and used to design new HIV inhibitors with increased potency and lower cytotoxicity. Of the scaffolds evaluated, specific chalcones were found to provide the best balance between anti-HIV potency and low host cell toxicity. Chalcone 8l was shown to inhibit different clinical isolates of HIV in a dose-dependent manner (e.g., IC50 typically⩽5μM). Inhibition of HIV infection experiments using TZM-bl cells demonstrated that chalcone 8l and flavonol 9c had IC50 values of 4.7μM and 10.4μM, respectively. These insights were used to design new chalcones 8o and 8p. Rewardingly, chalcones 8o and 8p (at 10μM) each gave >92% inhibition of viral propagation without impacting PM1 host cell viability. Inhibition of viral propagation significantly increased (60-90%) when PM1 cells were pre-incubated with chalcone 8o, but not with the related flavonol 9c. These results suggested that chalcone 8o may be of value as both a HIV prophylactic and therapy. In summary, O-benzyl-substituted chalcones were identified as promising anti-HIV agents for future investigation.

  11. Peltophorum africanum, a traditional South African medicinal plant, contains an anti HIV-1 constituent, betulinic acid.

    PubMed

    Theo, Andros; Masebe, Tracy; Suzuki, Yasuhiro; Kikuchi, Haruhisa; Wada, Shoko; Obi, Chikwelu Larry; Bessong, Pascal Obong; Usuzawa, Motoki; Oshima, Yoshiteru; Hattori, Toshio

    2009-02-01

    The biodiversity of medicinal plants in South Africa makes them rich sources of leading compounds for the development of novel drugs. Peltophorum africanum (Fabaceae) is a deciduous tree widespread in South Africa. The stem bark has been traditionally employed to treat diarrhoea, dysentery, sore throat, wounds, human immunodeficiency virus/ acquired immune deficiency syndrome (HIV/AIDS), venereal diseases and infertility. To evaluate these ethnobotanical clues and isolate lead compounds, butanol and ethyl acetate extracts of the stem bark were screened for their inhibitory activities against HIV-1 using MAGI CCR5+ cells, which are derived from HeLa cervical cancer cells and express HIV receptor CD4, a chemokine receptor CCR5 and HIV-LTR-beta- galactosidase. Bioassay-guided fractionation using silica gel chromatography was also conducted. The ethyl acetate and butanol extracts of the stem bark of Peltophorum africanum showed inhibitory activity against HIV-1, CXCR4 (X4) and CCR5 (R5) tropic viruses. The ethyl acetate and butanol extracts yielded previously reported anti-HIV compounds, (+)-catechin, a flavonoid, and bergenin, a C-galloylglycoside, respectively. Furthermore, we identified betulinic acid from the ethyl acetate fraction for the first time. The fractions, which contained betulinic acid, showed the highest selective index. We therefore describe the presence of betulinic acid, a not well-known anti-HIV compound, in an African medicinal herb, which has been used for therapy, and claim that betulinic acid is the predominant anti-HIV-1 constituent of Peltophorum africanum. These data suggest that betulinic acid and its analogues could be used as potential therapeutics for HIV-1 infection.

  12. Designed multiple ligands: an emerging anti-HIV drug discovery paradigm.

    PubMed

    Zhan, Peng; Liu, Xinyong

    2009-01-01

    Currently, the effect of AIDS single-target chemotherapy is severely compromised by the quick emergence of resistant HIV strains. Highly active antiretroviral therapy (HAART) combines HIV reverse transcriptase inhibitors with protease inhibitors or integrase inhibitors, and successfully suppresses HIV viral load to an undetectable level, dramatically improving the life quality of AIDS patients. However, the benefits of this approach are often compromised by poor patient compliance. Recently, there has been a move toward multicomponent drugs whereby two or more agents are coformulated in a single tablet to make dosing regimes simpler and thereby to improve patient compliance, but there are significant risks involved in the development of multicomponent drugs. Designed multiple ligands (DMLs) therapy as an emerging anti-HIV drug discovery paradigm, using a single entity to inhibit multitargets could yield improved patient compliance, thus reducing the likelihood of drug resistance. The exploration of such multifunctional ligands has proven valuable for anti-HIV leads discovery. However, presently many multifunctional scaffolds were first discovered by serendipity or screening; rational design by combining existing monofunctional scaffolds remains an enormous challenge. A key issue in the design of multiple ligands is attaining a balanced activity at each target of interest while simultaneously achieving a wider selectivity and a suitable pharmacokinetic profile. This review of literature examples introduce numerous attractive lead compounds, capable of interfering with different stages of HIV infection and AIDS pathogenesis, which reveals trends and insights that might provide valuable clues for novel anti-HIV drug design and help medicinal chemists discover the next generation of multiple ligands.

  13. Antiparietal cell antibody test

    MedlinePlus

    ... Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; Vitamin B12 - anti- ... may use this test to help diagnose pernicious anemia. Pernicious anemia is a decrease in red blood ...

  14. QSAR study and VolSurf characterization of anti-HIV quinolone library

    NASA Astrophysics Data System (ADS)

    Filipponi, Enrica; Cruciani, Gabriele; Tabarrini, Oriana; Cecchetti, Violetta; Fravolini, Arnaldo

    2001-03-01

    Antiviral quinolones are promising compounds in the search for new therapeutically effective agents for the treatment of AIDS. To rationalize the SAR for this new interesting class of anti-HIV derivatives, we performed a 3D-QSAR study on a library of 101 6-fluoro and 6-desfluoroquinolones, taken either from the literature or synthesized by us. The chemometric procedure involved a fully semiempirical minimization of the molecular structures by the AMSOL program, which takes into account the solvatation effect, and their 3D characterization by the VolSurf/GRID program. The QSAR analysis, based on PCA and PLS methods, shows the key structural features responsible for the antiviral activity.

  15. HIV Integrase Inhibitors with Nucleobase Scaffolds: Discovery of a Highly Potent anti-HIV Agent

    PubMed Central

    Nair, Vasu; Chi, Guochen; Ptak, Roger; Neamati, Nouri

    2008-01-01

    HIV integrase is essential for HIV replication. However, there are currently no integrase inhibitors in clinical use for AIDS. We have discovered a conceptually new β-diketo acid that is a powerful inhibitor of both the 3′-processing and strand transfer steps of HIV-1 integrase. The in vitro anti-HIV data of this inhibitor were remarkable as exemplified by its highly potent antiviral therapeutic efficacy against HIVTEKI and HIV-1NL4-3 replication in PBMC (TI >4,000 and >10,000, respectively). PMID:16420027

  16. Henrin A: A New Anti-HIV Ent-Kaurane Diterpene from Pteris henryi

    PubMed Central

    Li, Wan-Fei; Wang, Juan; Zhang, Jing-Jie; Song, Xun; Ku, Chuen-Fai; Zou, Juan; Li, Ji-Xin; Rong, Li-Jun; Pan, Lu-Tai; Zhang, Hong-Jie

    2015-01-01

    Henrin A (1), a new ent-kaurane diterpene, was isolated from the leaves of Pteris henryi. The chemical structure was elucidated by analysis of the spectroscopic data including one-dimensional (1D) and two-dimensional (2D) NMR spectra, and was further confirmed by X-ray crystallographic analysis. The compound was evaluated for its biological activities against a panel of cancer cell lines, dental bacterial biofilm formation, and HIV. It displayed anti-HIV potential with an IC50 value of 9.1 µM (SI = 12.2). PMID:26610490

  17. Antibody engineering for increased potency, breadth and half-life

    PubMed Central

    Sievers, Stuart A.; Scharf, Louise; West, Anthony P.; Bjorkman, Pamela J.

    2015-01-01

    Purpose of review This review highlights recent developments in HIV-1 antibody engineering and discusses the effects of increased polyreactivity on serum half-lives of engineered antibodies. Recent findings Recent studies have uncovered a wealth of information about the relationship between the sequences and efficacies of anti-HIV-1 antibodies through a combination of bioinformatics, structural characterization and in vivo studies. This knowledge has stimulated efforts to enhance antibody breadth and potency for therapeutic use. Although some engineered antibodies have shown increased polyreactivity and short half-lives, promising efforts are circumventing these problems. Summary Antibodies are desirable as therapeutics due to their ability to recognize targets with both specificity and high affinity. Furthermore, the ability of antibodies to stimulate Fc-mediated effector functions can increase their utility. Thus, mAbs have become central to strategies for the treatment of various diseases. Using both targeted and library-based approaches, antibodies can be engineered to improve their therapeutic properties. This article will discuss recent antibody engineering efforts to improve the breadth and potency of anti-HIV-1 antibodies. The polyreactivity of engineered HIV-1 bNAbs and the effect on serum half-life will be explored along with strategies to overcome problems introduced by engineering antibodies. Finally, advances in creating bispecific anti-HIV-1 reagents are discussed. PMID:25760931

  18. Hypervitaminosis B12 in maintenance hemodialysis patients receiving massive supplementation of vitamin B12.

    PubMed

    Mangiarotti, G; Canavese, C; Salomone, M; Thea, A; Pacitti, A; Gaido, M; Calitri, V; Pelizza, D; Canavero, W; Vercellone, A

    1986-11-01

    We have administered routinely a multivitamin preparation containing a megadose of B12 to 106 hemodialysis patients after dialysis treatments. We found that these patients had very high levels of serum vitamin B12 which returned to original values only after a period of three years after stopping the vitamin. Discontinuing therapy had no effect on hemoglobin, mean erythrocyte corpuscular volume, or motor nerve conduction velocity. It is not known whether maintaining a prolonged high level of vitamin B12 is harmful. However, animal and epidemiologic studies have suggested that both cobalamin and cobalt may be potentially toxic. In view of the absence of demonstrable benefit and the possible risk of toxicity, we believe that the use of such megadose vitamin compounds in dialysis patients should be re-evaluated.

  19. Notable Difference in anti-HIV Activity of Integrase Inhibitors as a Consequence of Geometric and Enantiomeric Configurations

    PubMed Central

    Okello, Maurice; Mishra, Sanjay; Nishonov, Malik; Nair, Vasu

    2013-01-01

    While some examples are known of integrase inhibitors that exhibit potent anti-HIV activity, there are very few cases reported of integrase inhibitors that show significant differences in anti-HIV activity that result from distinctions in cis-and trans-configurations as well as enantiomeric stereostructure. We describe here the design and synthesis of two enantiomeric trans-hydroxycyclopentyl carboxamides which exhibit notable difference in anti-HIV activity. This difference is explained through their binding interactions within the active site of the HIV-1 integrase intasome. The more active enantiomer 3 (EC50 25 nM) was relatively stable in human liver microsomes. Kinetic data revealed that its impact on key cytochrome P450 isozymes, as either an inhibitor or an activator, was minor, suggesting a favorable CYP profile. PMID:23746474

  20. Core-structure-inspired asymmetric addition reactions: enantioselective synthesis of dihydrobenzoxazinone- and dihydroquinazolinone-based anti-HIV agents.

    PubMed

    Li, Shen; Ma, Jun-An

    2015-11-07

    Dihydrobenzoxazinones and dihydroquinazolinones are the core units present in many anti-HIV agents, such as Efavirenz, DPC 961, DPC 963, and DPC 083. All these molecules contain a trifluoromethyl moiety at the quaternary stereogenic carbon center with S configuration. The enantioselective addition of carbon nucleophiles to ketones or cyclic ketimines could serve as a key step to access these molecules. This tutorial review provides an overview of significant advances in the synthesis of dihydrobenzoxazinone- and dihydroquinazolinone-based anti-HIV agents and relative analogues, with an emphasis on asymmetric addition reactions for the establishment of the CF3-containing quaternary carbon centers.

  1. Double Variational Binding—(SMILES) Conformational Analysis by Docking Mechanisms for Anti-HIV Pyrimidine Ligands

    PubMed Central

    Putz, Mihai V.; Dudaș, Nicoleta A.; Isvoran, Adriana

    2015-01-01

    Variational quantitative binding–conformational analysis for a series of anti-HIV pyrimidine-based ligands is advanced at the individual molecular level. This was achieved by employing ligand-receptor docking algorithms for each molecule in the 1,3-disubstituted uracil derivative series that was studied. Such computational algorithms were employed for analyzing both genuine molecular cases and their simplified molecular input line entry system (SMILES) transformations, which were created via the controlled breaking of chemical bonds, so as to generate the longest SMILES molecular chain (LoSMoC) and Branching SMILES (BraS) conformations. The study identified the most active anti-HIV molecules, and analyzed their special and relevant bonding fragments (chemical alerts), and the recorded energetic and geometric docking results (i.e., binding and affinity energies, and the surface area and volume of bonding, respectively). Clear computational evidence was also produced concerning the ligand-receptor pocket binding efficacies of the LoSMoc and BraS conformation types, thus confirming their earlier presence (as suggested by variational quantitative structure-activity relationship, variational-QSAR) as active intermediates for the molecule-to-cell transduction process. PMID:26295229

  2. Combinatorial anti-HIV gene therapy: using a multipronged approach to reach beyond HAART.

    PubMed

    Peterson, C W; Younan, P; Jerome, K R; Kiem, H-P

    2013-07-01

    The 'Berlin Patient', who maintains suppressed levels of HIV viremia in the absence of antiretroviral therapy, continues to be a standard bearer in HIV eradication research. However, the unique circumstances surrounding his functional cure are not applicable to most HIV(+) patients. To achieve a functional or sterilizing cure in a greater number of infected individuals worldwide, combinatorial treatments, targeting multiple stages of the viral life cycle, will be essential. Several anti-HIV gene therapy approaches have been explored recently, including disruption of the C-C chemokine receptor 5 (CCR5) and CXC chemokine receptor 4 (CXCR4) coreceptor loci in CD4(+) T cells and CD34(+) hematopoietic stem cells. However, less is known about the efficacy of these strategies in patients and more relevant HIV model systems such as non-human primates (NHPs). Combinatorial approaches, including genetic disruption of integrated provirus, functional enhancement of endogenous restriction factors and/or the use of pharmacological adjuvants, could amplify the anti-HIV effects of CCR5/CXCR4 gene disruption. Importantly, delivering gene disruption molecules to genetic sites of interest will likely require optimization on a cell type-by-cell type basis. In this review, we highlight the most promising gene therapy approaches to combat HIV infection, methods to deliver these therapies to hematopoietic cells and emphasize the need to target viral replication pre- and post-entry to mount a suitably robust defense against spreading infection.

  3. Anti-Tat and anti-HIV activities of trimers of n-alkylglycines.

    PubMed

    Márquez, Nieves; Sancho, Rocío; Macho, Antonio; Moure, Alejandra; Masip, Isabel; Messeguer, Angel; Muñoz, Eduardo

    2006-02-28

    Transcription of human immunodeficiency virus (HIV-1) is activated by viral Tat protein which regulates HIV-LTR transcription and elongation. In the present report, the evaluation of the anti-Tat activity of a combinatorial library composed of 5120 N-trialkylglycines is reported. The antiviral activity was studied through luciferase-based assays targeting the HIV-1 promoter activation induced by the HIV-1 Tat protein. We identified five peptoids with specific anti-HIV-1 Tat activity; none of these peptoids affected the binding of HIV-1 Tat protein to the viral TAR RNA. Using a recombinant-virus assay in which luciferase activity correlates with the rate of HIV-1 transcription we have detected that one of the five selected peptoids, NC37-37-15C, is a potent inhibitor of HIV-1-LTR transcription in both primary T lymphocytes and transformed cell lines. The inhibitory effect of NC37-37-15C, which is additive with azidothymidine (AZT), correlates with its ability to inhibit CTD phosphorylation and shows a suitable profile for development of novel anti-HIV-1 drugs. Likewise, the structural simplicity of N-alkylglycine oligomers makes these peptidomimetics amenable to structural manipulation, thus facilitating the optimisation of lead molecules for drug-like properties.

  4. Anti-HIV activity in vitro of MGN-3, an activated arabinoxylane from rice bran.

    PubMed

    Ghoneum, M

    1998-02-04

    MGN-3 an arabinoxylane from rice bran that has been enzymatically modified with extract from Hyphomycetes mycelia, was tested for anti-HIV activity in vitro. MGN-3 activity against HIV-1 (SF strain) was examined in primary cultures of peripheral blood mononuclear cells. MGN-3 inhibited HIV-1 replication by: (1) inhibition of HIV-1 p24 antigen production in a dose dependent manner--MGN-3 concentrations of 12.5, 25, 50, and 100 micrograms/ml showed 18.3, 42.8, 59, and 75% reduction in p24 antigen, respectively; and (2) inhibition of syncytia formation maximized (75%) at concentrations of 100 micrograms/ml. Further studies showed that ingestion of MGN-3 at concentration of 15 mg/kg/day resulted in a significant increase in T and B cell mitogen response at 2 months after treatment: 146% for PHA, 140% for Con A, and 136.6% for PWM mitogen. We conclude that MGN-3 possesses potent anti-HIV activity and in the absence of any notable side effects, MGN-3 shows promise as an agent for treating patients with AIDS.

  5. From Docking False-Positive to Active Anti-HIV Agent

    PubMed Central

    Barreiro, Gabriela; Kim, Joseph T.; Guimarães, Cristiano R. W.; Bailey, Christopher M.; Domaoal, Robert A.; Wang, Ligong; Anderson, Karen S.

    2008-01-01

    Virtual screening of the Maybridge library of ca. 70,000 compounds was performed using a similarity filter, docking, and MM-GB/SA post-processing to seek potential non-nucleoside inhibitors of HIV-1 reverse transcriptase (NNRTIs). Though known NNRTIs were retrieved well, purchase and assaying of representative, top-scoring compounds from the library failed to yield any active anti-HIV agents. However, the highest-ranked library compound, oxadiazole 1, was pursued as a potential “near-miss” with the BOMB program to seek constructive modifications. Subsequent synthesis and assaying of several polychloro-analogs did yield anti-HIV agents with EC50 values as low as 310 nM. The study demonstrates that it is possible to learn from a formally unsuccessful virtual-screening exercise and, with the aid of computational analyses, to evolve efficiently a false positive into a true active. In addition, the need for adequate structure validation was confirmed by the apparent misrepresentation of a purchased compound elsewhere as the present oxadiazole core compound, 16. PMID:17918923

  6. Vitamin B-12 and Depression: Are They Related?

    MedlinePlus

    ... What's the relationship between vitamin B-12 and depression? Answers from Daniel K. Hall-Flavin, M.D. Vitamin B-12 and ... B-6 and folate may be linked to depression. Low levels of a vitamin can result from ...

  7. Orthostatic hypotension as a manifestation of vitamin B12 deficiency.

    PubMed

    Ganjehei, Leila; Massumi, Ali; Razavi, Mehdi; Wilson, James M

    2012-01-01

    A 90-year-old woman with orthostatic hypotension and near-syncope was found to have a low-normal level of vitamin B(12) and no other medical findings that could explain her orthostasis. Her symptoms responded to vitamin B(12) replacement therapy. This case shows that vitamin B(12) deficiency can induce orthostatic hypotension and syncope that are correctable by vitamin B(12) replacement.

  8. 21 CFR 184.1945 - Vitamin B12.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Vitamin B12. 184.1945 Section 184.1945 Food and... Substances Affirmed as GRAS § 184.1945 Vitamin B12. (a) Vitamin B12, also known as cyanocobalamin (C63H88Co... is used in food at levels not to exceed current good manufacturing practice. Vitamin B12 also may...

  9. 21 CFR 184.1945 - Vitamin B12.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Vitamin B12. 184.1945 Section 184.1945 Food and... Substances Affirmed as GRAS § 184.1945 Vitamin B12. (a) Vitamin B12, also known as cyanocobalamin (C63H88Co... is used in food at levels not to exceed current good manufacturing practice. Vitamin B12 also may...

  10. 21 CFR 184.1945 - Vitamin B 12..

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Vitamin B 12.. 184.1945 Section 184.1945 Food and... Substances Affirmed as GRAS § 184.1945 Vitamin B 12.. (a) Vitamin B12, also known as cyanocobalamin (C63H88Co... is used in food at levels not to exceed current good manufacturing practice. Vitamin B12 also may...

  11. 21 CFR 184.1945 - Vitamin B12.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Vitamin B12. 184.1945 Section 184.1945 Food and....1945 Vitamin B12. (a) Vitamin B12, also known as cyanocobalamin (C63H88CoN14O14P, CAS Reg. No. 68-0919... exceed current good manufacturing practice. Vitamin B12 also may be used in infant formula in...

  12. 21 CFR 184.1945 - Vitamin B12.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Vitamin B12. 184.1945 Section 184.1945 Food and... Substances Affirmed as GRAS § 184.1945 Vitamin B12. (a) Vitamin B12, also known as cyanocobalamin (C63H88Co... is used in food at levels not to exceed current good manufacturing practice. Vitamin B12 also may...

  13. Degradation of vitamin B12 in dietary supplements.

    PubMed

    Yamada, Keiko; Shimodaira, Michiko; Chida, Seiko; Yamada, Noriko; Matsushima, Norio; Fukuda, Morimichi; Yamada, Shoji

    2008-01-01

    Beverages and solid dietary supplements rich in various added vitamins and minerals have recently become available. It seems reasonable to consider that the intake of these foods is convenient for easy ingestion of nutrients, but problems caused by blending different nutrients in high concentrations have arisen. We focused on vitamin B12 (B12) among vitamins and determined the B12 contents of beverages and solid dietary supplements purchased from a retail shop. The B12 contents of three of five beverages were less than stated on the labels. On the other hand, certain beverages unexpectedly contained much more B12 than stated on the labels. In these beverages the amount of B12 decreased rapidly with time, whereas B12 content was lower than stated on the label in only one of four solid dietary supplements. The content of B12 was affected by storage time, light exposure, temperature and vitamin C. From experimental analysis with a competitive binding assay method employing a ACS Chemiluminescent B12 kit, examining differential binding by intrinsic factors and spectral analysis of B12, it was determined that some of the B12 might have been converted into B12 analogues or small degradation products by multinutrient interaction during storage.

  14. 21 CFR 582.5945 - Vitamin B12.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Vitamin B12. 582.5945 Section 582.5945 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5945 Vitamin B12. (a) Product. Vitamin B12. (b) Conditions of use. This substance...

  15. 21 CFR 582.5945 - Vitamin B 12.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Vitamin B 12. 582.5945 Section 582.5945 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5945 Vitamin B 12. (a) Product. Vitamin B12. (b) Conditions of use. This substance...

  16. 21 CFR 582.5945 - Vitamin B12.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Vitamin B12. 582.5945 Section 582.5945 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5945 Vitamin B12. (a) Product. Vitamin B12. (b) Conditions of use. This substance...

  17. 21 CFR 582.5945 - Vitamin B 12.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Vitamin B 12. 582.5945 Section 582.5945 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5945 Vitamin B 12. (a) Product. Vitamin B12. (b) Conditions of use. This substance...

  18. 21 CFR 582.5945 - Vitamin B12.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Vitamin B12. 582.5945 Section 582.5945 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5945 Vitamin B12. (a) Product. Vitamin B12. (b) Conditions of use. This substance...

  19. Radiolysis of cyanocobalamin (vitamin B 12)

    NASA Astrophysics Data System (ADS)

    Juanchi, X.; Albarran, G.; Negron-Mendoza, A.

    2000-03-01

    Research on the radiolysis of vitamins is of considerable interest since these compounds are important nutritional constituents in foods and in dietetic supplements. In spite of these considerations there are few data and very often difficult to compare for the radiolytic behavior of vitamins. In this work we focused our attention on to the study of the radiolysis of cyanocobalamin (vitamin B 12) in solid state and in aqueous solutions. The procedure was followed by HPLC and UV-spectroscopy. The results obtained in aqueous solutions showed a dependence of the decomposition as a linear function of the dose. The G of decomposition for a 1×10 -5 M solution was 3.3. In the solid state the vitamin was very stable towards the irradiation in the conditions used in this study with a G=2.1×10 -3. A study made with Serratia marcescens as a microbiological contaminant showed that at the sterilization dose there is a destruction of the vitamin in aqueous solution. In the solid state the degree of decomposition was 7%.

  20. Thermotoga lettingae can salvage cobinamide to synthesize vitamin B12.

    PubMed

    Butzin, Nicholas C; Secinaro, Michael A; Swithers, Kristen S; Gogarten, J Peter; Noll, Kenneth M

    2013-11-01

    We recently reported that the Thermotogales acquired the ability to synthesize vitamin B12 by acquisition of genes from two distantly related lineages, Archaea and Firmicutes (K. S. Swithers et al., Genome Biol. Evol. 4:730-739, 2012). Ancestral state reconstruction suggested that the cobinamide salvage gene cluster was present in the Thermotogales' most recent common ancestor. We also predicted that Thermotoga lettingae could not synthesize B12 de novo but could use the cobinamide salvage pathway to synthesize B12. In this study, these hypotheses were tested, and we found that Tt. lettingae did not synthesize B12 de novo but salvaged cobinamide. The growth rate of Tt. lettingae increased with the addition of B12 or cobinamide to its medium. It synthesized B12 when the medium was supplemented with cobinamide, and no B12 was detected in cells grown on cobinamide-deficient medium. Upstream of the cobinamide salvage genes is a putative B12 riboswitch. In other organisms, B12 riboswitches allow for higher transcriptional activity in the absence of B12. When Tt. lettingae was grown with no B12, the salvage genes were upregulated compared to cells grown with B12 or cobinamide. Another gene cluster with a putative B12 riboswitch upstream is the btuFCD ABC transporter, and it showed a transcription pattern similar to that of the cobinamide salvage genes. The BtuF proteins from species that can and cannot salvage cobinamides were shown in vitro to bind both B12 and cobinamide. These results suggest that Thermotogales species can use the BtuFCD transporter to import both B12 and cobinamide, even if they cannot salvage cobinamide.

  1. Thermotoga lettingae Can Salvage Cobinamide To Synthesize Vitamin B12

    PubMed Central

    Butzin, Nicholas C.; Secinaro, Michael A.; Swithers, Kristen S.; Gogarten, J. Peter

    2013-01-01

    We recently reported that the Thermotogales acquired the ability to synthesize vitamin B12 by acquisition of genes from two distantly related lineages, Archaea and Firmicutes (K. S. Swithers et al., Genome Biol. Evol. 4:730–739, 2012). Ancestral state reconstruction suggested that the cobinamide salvage gene cluster was present in the Thermotogales' most recent common ancestor. We also predicted that Thermotoga lettingae could not synthesize B12 de novo but could use the cobinamide salvage pathway to synthesize B12. In this study, these hypotheses were tested, and we found that Tt. lettingae did not synthesize B12 de novo but salvaged cobinamide. The growth rate of Tt. lettingae increased with the addition of B12 or cobinamide to its medium. It synthesized B12 when the medium was supplemented with cobinamide, and no B12 was detected in cells grown on cobinamide-deficient medium. Upstream of the cobinamide salvage genes is a putative B12 riboswitch. In other organisms, B12 riboswitches allow for higher transcriptional activity in the absence of B12. When Tt. lettingae was grown with no B12, the salvage genes were upregulated compared to cells grown with B12 or cobinamide. Another gene cluster with a putative B12 riboswitch upstream is the btuFCD ABC transporter, and it showed a transcription pattern similar to that of the cobinamide salvage genes. The BtuF proteins from species that can and cannot salvage cobinamides were shown in vitro to bind both B12 and cobinamide. These results suggest that Thermotogales species can use the BtuFCD transporter to import both B12 and cobinamide, even if they cannot salvage cobinamide. PMID:24014541

  2. Free and Total Vitamin B12 in Cerebrospinal Fluid

    PubMed Central

    Kidd, Honor M.; Gould, C. E. G.; Thomas, J. W.

    1963-01-01

    Free and total vitamin B12 levels in serum and cerebrospinal fluid (CSF) were bioassayed, since there were no available data on the relationship between free and total vitamin B12 in CSF or between free vitamin in serum and CSF vitamin B12. The subjects were 43 neurological patients. Serum levels were normal in 40 of 43 patients. Values for free and total vitamin B12 in CSF were the same in 42 of 43 patients. Mean CSF vitamin B12 was 21 μμg./ml. In 17 cases CSF vitamin B12 equalled free vitamin B12 level in serum, in 16 cases CSF vitamin B12 was lower than the free level in serum, and in 10 cases CSF vitamin B12 was higher than the free vitamin level in serum. There was no apparent diagnostic correlation. The findings suggest that vitamin B12 is not bound in CSF and that there is some selective control of passage of vitamin B12 across the blood-CSF barrier. PMID:14032478

  3. Evaluation of LIAISON® XL system for HBsAg, and anti-HCV and anti-HIV/Ag p24.

    PubMed

    De Paschale, Massimo; Manco, Maria Teresa; Belvisi, Luisa; Cagnin, Debora; Cerulli, Teresa; Paganini, Alessia; Arpino, Olivia; Cianflone, Annalisa; Agrappi, Carlo; Mirri, Paola; Clerici, Pierangelo

    2017-03-01

    The aim of this study was to compare the data obtained using the new LIAISON® XL chemiluminescence system to search for HBsAg, anti-HCV, and anti-HIV1-2/p24 Ag with those obtained using the VITROS system currently adopted by the Microbiology Unit of the Hospital of Legnano. Routine samples of patients who were referred by practitioners for the determination of HBsAg (1,000 samples) and/or anti-HCV (1,002 samples) and/or anti-HIV1-2 (995 samples) were simultaneously analyzed using both systems. The concordant positive and discordant samples were re-examined for confirmation by means of an HBsAg neutralization assay, anti-HCV immunoblot, or anti-HIV1-2 Western blot; HBV-DNA, or HCV-RNA or HIV-RNA was also sought in the discordant samples. Samples of patients known to be positive were tested (100 HBsAg positive, 100 anti-HCV positive, and 100 HIV 1-2 positive) as well throughout treatment, with viremia levels becoming undetectable after treatment. The HBsAg, anti-HCV, and anti-HIV1-2 concordance between the two systems in routine series was respectively 99.8%, 98.5% and 99.7%, and 100% for all markers in samples known positive. The various molecular biology and confirmatory tests of the discordant samples were all negative (except for one anti-HCV positive sample). Measure of Cohen's kappa coefficient for HBsAg, anti-HCV, and anti-HIV gave K values of respectively 0.992, 0.946, and 0.980. In conclusion, the performance of the LIAISON® XL system in the routine laboratory determination for all three markers was comparable with that of the VITROS system. J. Med. Virol. 89:489-496, 2017. © 2016 Wiley Periodicals, Inc.

  4. Anti-HIV-1 Activity of Flavonoid Myricetin on HIV-1 Infection in a Dual-Chamber In Vitro Model

    PubMed Central

    Pasetto, Silvana; Pardi, Vanessa; Murata, Ramiro Mendonça

    2014-01-01

    HIV infection by sexual transmission remains an enormous global health concern. More than 1 million new infections among women occur annually. Microbicides represent a promising prevention strategy that women can easily control. Among emerging therapies, natural small molecules such as flavonoids are an important source of new active substances. In this study we report the in vitro cytotoxicity and anti-HIV-1 and microbicide activity of the following flavonoids: Myricetin, Quercetin and Pinocembrin. Cytotoxicity tests were conducted on TZM-bl, HeLa, PBMC, and H9 cell cultures using 0.01–100 µM concentrations. Myricetin presented the lowest toxic effect, with Quercetin and Pinocembrin relatively more toxic. The anti-HIV-1 activity was tested with TZM-bl cell plus HIV-1 BaL (R5 tropic), H9 and PBMC cells plus HIV-1 MN (X4 tropic), and the dual tropic (X4R5) HIV-1 89.6. All flavonoids showed anti-HIV activity, although Myricetin was more effective than Quercetin or Pinocembrin. In TZM-bl cells, Myricetin inhibited ≥90% of HIV-1 BaL infection. The results were confirmed by quantification of HIV-1 p24 antigen in supernatant from H9 and PBMC cells following flavonoid treatment. In H9 and PBMC cells infected by HIV-1 MN and HIV-1 89.6, Myricetin showed more than 80% anti-HIV activity. Quercetin and Pinocembrin presented modest anti-HIV activity in all experiments. Myricetin activity was tested against HIV-RT and inhibited the enzyme by 49%. Microbicide activities were evaluated using a dual-chamber female genital tract model. In the in vitro microbicide activity model, Myricetin showed promising results against different strains of HIV-1 while also showing insignificant cytotoxic effects. Further studies of Myricetin should be performed to identify its molecular targets in order to provide a solid biological foundation for translational research. PMID:25546350

  5. Identification of anti-HIV active dicaffeoylquinic- and tricaffeoylquinic acids in Helichrysum populifolium by NMR-based metabolomic guided fractionation.

    PubMed

    Heyman, Heino Martin; Senejoux, François; Seibert, Isabell; Klimkait, Thomas; Maharaj, Vinesh Jaichand; Meyer, Jacobus Johannes Marion

    2015-06-01

    South Africa being home to more than 35% of the world's Helichrysum species (c.a. 244) of which many are used in traditional medicine, is seen potentially as a significant resource in the search of new anti-HIV chemical entities. It was established that five of the 30 Helichrysum species selected for this study had significant anti-HIV activity ranging between 12 and 21 μg/mL (IC50) by using an in-house developed DeCIPhR method on a full virus model. Subsequent toxicity tests also revealed little or no toxicity for these active extracts. With the use of NMR-based metabolomics, the search for common chemical characteristics within the plant extract was conducted, which resulted in specific chemical shift areas identified that could be linked to the anti-HIV activity of the extracts. The NMR chemical shifts associated with the activity were identified to be 2.56-3.08 ppm, 5.24-6.28 ppm, 6.44-7.04 ppm and 7.24-8.04 ppm. This activity profile was then used to guide the fractionation process by narrowing down and focusing the fractionation and purification processes to speed up the putative identification of five compounds with anti-HIV activity in the most active species, Helichrysum populifolium. The anti-HIV compounds identified for the first time from H. populifolium were three dicaffeoylquinic acid derivatives, i.e. 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid as well as two tricaffeoylquinic acid derivatives i.e. 1,3,5-tricaffeoylquinic acid and either 5-malonyl-1,3,4-tricaffeoylquinic or 3-malonyl-1,4,5-tricaffeoylquinic acid, with the latter being identified for the first time in the genus.

  6. Chemoenzymatic Syntheses and Anti-HIV-1 Activity of Glucose-Nucleoside Conjugates as Prodrugs

    PubMed Central

    Rodríguez-Pérez, Tatiana; Fernández, Susana; Sanghvi, Yogesh S.; Detorio, Mervi; Schinazi, Raymond F.; Gotor, Vicente; Ferrero, Miguel

    2010-01-01

    Phosphodiester linked conjugates of various nucleosides such as d4U, d4T, IdUrd, ddI, ddA, virazole, ara-A and ara-C containing a glucosyl moiety have been described. These compounds were designed to act as prodrugs, where the corresponding 5′-monophosphates may be generated intracellularly. The synthesis of the glycoconjugates was achieved in good yields by condensation of a glucosyl phosphoramidite 7 with nucleosides in the presence of an activating agent. It was demonstrated that the glucose-conjugates improve water solubility of the nucleoside analogues, for example up to 31-fold for ara-A conjugate compared to ara-A alone. The new conjugates were tested for their anti-HIV-1 activity in human lymphocytes. These derivatives offer a convenient design for potential prodrug candidates with the possibility to improve the physicochemical properties and therapeutic activity of nucleoside analogues. PMID:21077659

  7. [Asymmetry in international relations, industrial property rights and anti-HIV medication].

    PubMed

    Costa-Couto, Maria Helena; Nascimento, Alvaro César

    2008-01-01

    This paper analyzes the asymmetry in the international relations as refers to the recognition of industrial property rights in the pharmaceutical industry. It focuses on the impact of such relations upon the access to ARV medication, an issue of worldwide interest due to its connection with the development of the nations. Clashing interests and the position taken by some countries in their patent laws point to a scenario less favorable for the access of peripheral countries to anti-HIV/AIDS medication. On the other hand, it seems that the success of the Brazilian STD/AIDS program in negotiating ARV prices will open new possibilities. The solution may be the internal strengthening of the National States and the active role played by the Agencies of the United Nations System in defense of the collective human interests.

  8. 2-Aminothiazolones as Anti-HIV Agents That Act as gp120-CD4 Inhibitors

    PubMed Central

    Tiberi, Marika; Tintori, Cristina; Ceresola, Elisa Rita; Fazi, Roberta; Zamperini, Claudio; Calandro, Pierpaolo; Franchi, Luigi; Selvaraj, Manikandan; Botta, Lorenzo; Sampaolo, Michela; Saita, Diego; Ferrarese, Roberto; Clementi, Massimo

    2014-01-01

    We report here the synthesis of 2-aminothiazolones along with their biological properties as novel anti-HIV agents. Such compounds have proven to act through the inhibition of the gp120-CD4 protein-protein interaction that occurs at the very early stage of the HIV-1 entry process. No cytotoxicity was found for these compounds, and broad antiviral activities against laboratory strains and pseudotyped viruses were documented. Docking simulations have also been applied to predict the mechanism, at the molecular level, by which the inhibitors were able to interact within the Phe43 cavity of HIV-1 gp120. Furthermore, a preliminary absorption, distribution, metabolism, and excretion (ADME) evaluation was performed. Overall, this study led the basis for the development of more potent HIV entry inhibitors. PMID:24614386

  9. The anti-HIV activity of the phytochemical alpha-terthienyl.

    PubMed

    Hudson, J B; Harris, L; Teeple, A; Towers, G H

    1993-01-01

    The plant trithiophene, alpha-terthienyl (alpha T), was evaluated for activity against the human immunodeficiency virus (HIV-1). Antiviral activity specifically required long wavelength light (UVA, 320-400 nm). The compound had little or no activity in visible light or in the dark. The anti-HIV effect was UVA-dose dependent and was proportional to the concentration of alpha T, according to several parameters of virus infectivity and replication. The efficacy was decreased to some extent by the presence of bovine serum in the reactions; but under optimal conditions 0.1 microgram/ml. alpha T (3 x 10(-7) M) could inactivate 10(4)-10(5) infectious particles. In contrast poliovirus and Coxsackievirus infectivity were relatively resistant to alpha T + UVA.

  10. Electrochemical impediometric detection of anti-HIV drug taking gold nanorods as a sensing interface.

    PubMed

    Narang, Jagriti; Malhotra, Nitesh; Singh, Gajendra; Pundir, C S

    2015-04-15

    In present work, gold nanorods were used for amplification of electrochemical sensing of anti-HIV replication drug i.e. deferiprone. Gold nanorods (nano Au) deposited onto pencil graphite electrode (PGE) has been utilized for covalent immobilization of horse radish peroxidase (HRP), via glutaraldehyde (Glu), for deferiprone detection using impedimetric technique. Gold nanorods (nano Au) prepared were characterized by TEM and XRD. The resulting nano Au sensor exhibited a good response to deferiprone with a wide linear range (0.005-1000µM) and a low detection limit 0.005µM. The biosensor also showed a short response time (within 15s). In addition, the biosensor exhibited high reproducibility, good storage stability and anti-interference ability. The applicability of the nano Au sensor is to determine deferiprone level in spiked urine and serum samples.

  11. In vitro testing of African traditional medicines for cytotoxic, immune modulatory and anti-HIV activities.

    PubMed

    Gqaleni, Nceba; Ngcobo, Mlungisi; Parboosing, Raveen; Naidoo, Anneta

    2012-01-01

    African Traditional Medicines (ATMs) serve as a major source of primary healthcare for African people. The reasons for their use range from easy access, affordability, beliefs in traditional systems and long term safety. ATMs have been used to treat individuals infected with HIV and therefore need scientific validation; a view supported by Traditional Health Practitioners (THPs). This study aimed to evaluate the in vitro cytotoxicity, immune modulatory and anti-HIV activities of traditional multiple herbal preparations from local THPs. Ugambu, Ihashi, Product Nene, Product Blue, SPNa and SDKc ATM were supplied by local THPs. Changes in adenosine triphosphate (ATP) & glutathione (GSH) over 24 hours were measured using luminometry. Changes in 12 cytokines were assayed using an ELISA-based absorbance assay. Protective effects against HIV killing of MT-4 cells were tested using the XTT assay and antiviral activity was measured using an HIV-1 viral load assay. Cyclosporine and AZT were used as positive controls. Ugambu, Ihashi, Product Nene and SDKc induced a dose dependent toxicity on treated PBMCs by reducing ATP and GSH at high doses (p< 0.001). These medicinal preparations, along with SPNa, showed immunomodulatory activity by significantly (p< 0.001) changing the secretion of pro-inflammatory cytokines. Product Blue stimulated the levels of ATP and GSH in treated PBMCs at all doses however this product did not show any immunomodulatory activity on cytokine secretion when compared to control cells. Ugambu, Ihashi, Product Nene showed promising anti-HIV activity relative to AZT (p< 0.01). This study has shown that some of these traditional medicinal preparations have at least one or all the properties of immunostimulation, immunomodulation or antiretroviral effects. The mechanism of action of the shown activities should further be investigated.

  12. Nanoparticles-in-film for the combined vaginal delivery of anti-HIV microbicide drugs.

    PubMed

    Cunha-Reis, Cassilda; Machado, Alexandra; Barreiros, Luísa; Araújo, Francisca; Nunes, Rute; Seabra, Vítor; Ferreira, Domingos; Segundo, Marcela A; Sarmento, Bruno; das Neves, José

    2016-12-10

    Combining two or more antiretroviral drugs in one medical product is an interesting but challenging strategy for developing topical anti-HIV microbicides. We developed a new vaginal delivery system comprising the incorporation of nanoparticles (NPs) into a polymeric film base - NPs-in-film - and tested its ability to deliver tenofovir (TFV) and efavirenz (EFV). EFV-loaded poly(lactic-co-glycolic acid) NPs were incorporated alongside free TFV into fast dissolving films during film manufacturing. The delivery system was characterized for physicochemical properties, as well as genital distribution, local and systemic 24h pharmacokinetics (PK), and safety upon intravaginal administration to mice. NPs-in-film presented suitable technological, mechanical and cytotoxicity features for vaginal use. Retention of NPs in vivo was enhanced both in vaginal lavages and tissue when associated to film. PK data evidenced that vaginal drug levels rapidly decreased after administration but NPs-in-film were still able to enhance drug concentrations of EFV. Obtained values for area-under-the-curve for EFV were around one log10 higher than those for the free drugs in aqueous vehicle (phosphate buffered saline). Film alone also contributed to higher and more prolonged local drug levels as compared to the administration of TFV and EFV in aqueous vehicle. Systemic exposure to both drugs was low. NPs-in-film was found to be safe upon once daily vaginal administration to mice, with no significant genital histological changes or major alterations in cytokine/chemokine profiles being observed. Overall, the proposed NPs-in-film system seems to be an interesting delivery platform for developing combination vaginal anti-HIV microbicides.

  13. Flazinamide, a novel {beta}-carboline compound with anti-HIV actions

    SciTech Connect

    Wang Yunhua; Tang Jianguo; Wang Ruirui; Yang Liumeng; Dong Zejun; Du Li; Shen Xu; Liu Jikai; Zheng Yongtang . E-mail: zhengyt@mail.kiz.ac.cn

    2007-04-20

    A {beta}-carboline compound, flazin isolated from Suillus granulatus has been shown weak anti-HIV-1 activity. Based on the structure of flazin, flazinamide [1-(5'- hydromethyl-2'-furyl)-{beta}-carboline-3-carboxamide] was synthesized and its anti-HIV activities were evaluated in the present study. The cytotoxicity of flazinamide was about 4.1-fold lower than that of flazin. Flazinamide potently reduced syncytium formation induced by HIV-1IIIB with EC50 value of 0.38 {mu}M, the EC50 of flazinamide was about 6.2-fold lower than that of flazin. Flazinamide also inhibited HIV-2ROD and HIV-2CBL-20 infection with EC50 values of 0.57 and 0.89 {mu}M, respectively. Flazinamide reduced p24 antigen expression in HIV-1IIIB acute infected C8166 and in clinical isolated strain HIV-1KM018 infected PBMC, with EC50 values of 1.45 and 0.77 {mu}M, respectively. Flazinamide did not suppress HIV-1 replication in chronically infected H9 cells. Flazinamide blocked the fusion between normal cells and HIV-1 or HIV-2 chronically infected cells. It weakly inhibited activities of recombinant HIV-1 reverse transcriptase, protease or integrase at higher concentrations. In conclusion, the conversion of the carboxyl group in 3 position of flazin markedly enhanced the anti-viral activity (TI value increased from 12.1 to 312.2) and flazinamide might interfere in the early stage of HIV life cycle.

  14. Electron densities of three B12 vitamins.

    PubMed

    Mebs, Stefan; Henn, Julian; Dittrich, Birger; Paulmann, Carsten; Luger, Peter

    2009-07-23

    The electron densities of the three natural B(12)-vitamins, two of them being essential cofactors for animal life, were determined in a procedure combining high-order X-ray data collection at low to very low temperatures with high-level density functional calculations. In a series of extensive experimental attempts, a high-order data set of adenosylcobalamin (AdoCbl) could be collected to a resolution of sin theta/lambda = 1.00 A(-1) at 25 K. This modification contains only minor disorder at the solvent bulk. For methylcobalamin (MeCbl), only a severely disordered modification was found (sin theta/lambda = 1.00 A(-1), 100 K, measured with synchrotron radiation). The already published data set of cyanocobalamin (CNCbl) (sin theta/lambda = 1.25 A(-1), 100 K) was reintegrated to guarantee similar treatment of the three compounds and cut to sin theta/lambda = 1.11 A(-1) to obtain a higher degree of completeness and redundancy. On the basis of these accurate experimental geometries of AdoCbl, MeCbl, and CNCbl, state-of-the-art density functional calculations, single-point calculations, and geometry optimizations were performed on model compounds at the BP86/TZVP level of theory to evaluate the electronic differences of the three compounds. AdoCbl and MeCbl are known to undergo different reaction paths in the body. Thus, the focus was directed toward the characterization of the dative Co-C(ax) and Co-N(ax) bonds, which were quantifed by topological parameters, including energy densities; the source function including local source; and the electron localizability indicator (ELI-D), respectively. The source function reveals the existence of delocalized interactions between the corrin macrocycle and the axial ligands. The ELI-D indicates unsaturated Co-C(ax) bonding basins for the two biochemically active cofactors, but not for CNCbl, where a population of 2.2e is found. This may be related to significant pi-backbonding, which is supported by the delocalization index, delta

  15. A vitamin B12 transporter in Mycobacterium tuberculosis

    PubMed Central

    Gopinath, Krishnamoorthy; Venclovas, Česlovas; Ioerger, Thomas R.; Sacchettini, James C.; McKinney, John D.; Mizrahi, Valerie; Warner, Digby F.

    2013-01-01

    Vitamin B12-dependent enzymes function in core biochemical pathways in Mycobacterium tuberculosis, an obligate pathogen whose metabolism in vivo is poorly understood. Although M. tuberculosis can access vitamin B12 in vitro, it is uncertain whether the organism is able to scavenge B12 during host infection. This question is crucial to predictions of metabolic function, but its resolution is complicated by the absence in the M. tuberculosis genome of a direct homologue of BtuFCD, the only bacterial B12 transport system described to date. We applied genome-wide transposon mutagenesis to identify M. tuberculosis mutants defective in their ability to use exogenous B12. A small proportion of these mapped to Rv1314c, identifying the putative PduO-type ATP : co(I)rrinoid adenosyltransferase as essential for B12 assimilation. Most notably, however, insertions in Rv1819c dominated the mutant pool, revealing an unexpected function in B12 acquisition for an ATP-binding cassette (ABC)-type protein previously investigated as the mycobacterial BacA homologue. Moreover, targeted deletion of Rv1819c eliminated the ability of M. tuberculosis to transport B12 and related corrinoids in vitro. Our results establish an alternative to the canonical BtuCD-type system for B12 uptake in M. tuberculosis, and elucidate a role in B12 metabolism for an ABC protein implicated in chronic mycobacterial infection. PMID:23407640

  16. Vitamin B12 assays compared by use of patients sera with low vitamin B12 content

    SciTech Connect

    Sheridan, B.L.; Pearce, L.C.

    1985-05-01

    The authors compared four radioisotope dilution (RD) methods and a microbiological assay for measuring concentrations of vitamin B12 in a selected panel of serum samples from patients known to be deficient in the vitamin. Low (less than 100 ng/L) and borderline (100-180 ng/L) results were similar between methods, but use of the manufacturers recommended ranges for borderline results would have changed the diagnostic classifications for 22 of 38 samples. Results of all the RD methods inter-correlated well, but less so with the microbiological assay. Borderline, nondiagnostic results were common to all methods, and no apparent advantage was gained from using the microbiological assay.

  17. Effect of vitamin B12 deficiency on otoacoustic emissions.

    PubMed

    Karli, R; Gül, A; Uğur, B

    2013-08-01

    The aim of this study was to investigate the possible association between otoacoustic emission (OAE) values and cochlear function in patients with vitamin B12 deficiency and no evidence of symptomatic hearing loss. Two groups were studied: Group 1: patients with vitamin B12 deficiency; Group 2: a matched control group of patients with normal vitamin B12 levels. There was no evidence of symptomatic hearing loss in either group. Transiently evoked OAEs (TEOAEs) and spontaneous OAEs (SOAEs) were recorded. A comparative analysis of the studied parameters revealed that results at TEOAE 1000, SOAEs 1500 and SOAEs 4000 Hz were somewhat lower in the vitamin B12 deficient group compared with the control group. According to our findings, there was a significant association between vitamin B12 deficiency and cochlear dysfunction. We recommend that routine vitamin B12 serum levels be determined when evaluating patients for symptomatic hearing loss.

  18. Vitamin B12-Containing Plant Food Sources for Vegetarians

    PubMed Central

    Watanabe, Fumio; Yabuta, Yukinori; Bito, Tomohiro; Teng, Fei

    2014-01-01

    The usual dietary sources of Vitamin B12 are animal-derived foods, although a few plant-based foods contain substantial amounts of Vitamin B12. To prevent Vitamin B12 deficiency in high-risk populations such as vegetarians, it is necessary to identify plant-derived foods that contain high levels of Vitamin B12. A survey of naturally occurring plant-derived food sources with high Vitamin B12 contents suggested that dried purple laver (nori) is the most suitable Vitamin B12 source presently available for vegetarians. Furthermore, dried purple laver also contains high levels of other nutrients that are lacking in vegetarian diets, such as iron and n-3 polyunsaturated fatty acids. Dried purple laver is a natural plant product and it is suitable for most people in various vegetarian groups. PMID:24803097

  19. Vitamin B12 deficiency after irradiation for bladder carcinoma

    SciTech Connect

    Kinn, A.C.; Lantz, B.

    1984-05-01

    Vitamin B12 deficiency was found in 10 of 41 patients who underwent radiotherapy before cystectomy with Bricker urinary diversion for carcinoma of the bladder. Of 13 patients given full irradiation because of inoperable bladder cancer 5 had malabsorption of vitamin B12. Serum folic acid was normal in these patients, indicating predominantly ileal irradiation sequelae. Routine evaluation of serum vitamin B12 after radiotherapy is recommended so that appropriate medication can be given, if possible before neurological symptoms appear.

  20. Folic acid fortification: why not vitamin B12 also?

    PubMed

    Selhub, Jacob; Paul, Ligi

    2011-01-01

    Folic acid fortification of cereal grains was introduced in many countries to prevent neural tube defect occurrence. The metabolism of folic acid and vitamin B12 intersect during the transfer of the methyl group from 5-methyltetrahydrofolate to homocysteine catalyzed by B12-dependent methioine synthase. Regeneration of tetrahydrofolate via this reaction makes it available for synthesis of nucleotide precursors. Thus either folate or vitamin B12 deficiency can result in impaired cell division and anemia. Exposure to extra folic acid through fortification may be detrimental to those with vitamin B12 deficiency. Among participants of National Health And Nutrition Examination Survey with low vitamin B12 status, high serum folate (>59 nmol/L) was associated with higher prevalence of anemia and cognitive impairment when compared with normal serum folate. We also observed an increase in the plasma concentrations of total homocysteine and methylmalonic acid (MMA), two functional indicators of vitamin B12 status, with increase in plasma folate under low vitamin B12 status. These data strongly imply that high plasma folate is associated with the exacerbation of both the biochemical and clinical status of vitamin B12 deficiency. Hence any food fortification policy that includes folic acid should also include vitamin B12.

  1. Vitamin B12 Deficiency due to Chlorofluorocarbon: A Case Report.

    PubMed

    Bhaskar, Hemlata; Chaudhary, Rekha

    2010-01-01

    Background. Vitamin B12 is vital for optimal functioning of various organ systems but more importantly the central nervous system and the hematological system. Deficiency of vitamin B12 clinically manifests as excessive daytime fatigue, memory difficulties, encephalopathy, myelopathy, peripheral neuropathy, and optic neuropathy. In occupational medicine, vitamin B12 deficiency has been reported with exposure to nitrous oxide in health care workers. However, not much is known about exposure to Freons in other industries and vitamin B12 deficiency. Aim. We are reporting a case of vitamin B12 deficiency in the setting of exposure to chlorofluorocarbon (CFC) gases. Case Report. A 55-year-old male refrigerator mechanic experienced recurrent visual symptoms, which included diplopia and blurring. A complete workup was done and was significant of vitamin B12 deficiency. However, his B12 levels were refractory to supplementation. Appropriate precautions at workplace improved patient's symptoms and were associated with significant improvement in B12 levels. Conclusion. To the best of our knowledge, this is the first reported case of vitamin B12 deficiency (that remains refractory to supplementation) in the setting of exposure to Freon gases.

  2. Interaction between excess folate and low vitamin B12 status.

    PubMed

    Paul, Ligi; Selhub, Jacob

    2017-02-01

    Current epidemiological evidence suggests that an imbalance of high folate status and low vitamin B12 status is associated with negative health outcomes in older adults and children. Such an imbalance during pregnancy also predisposes women to diabetes and their offspring to insulin resistance and adiposity and low birthweight. In older adults, vitamin B12 status can remain low despite adequate intake due to age-related decline in vitamin B12 absorption. Pregnant women are exposed to folic acid at varying doses depending on the prenatal care prescribed in different countries. This review summarizes the current knowledge on the interaction between folate and vitamin B12 and the associated health outcomes.

  3. Oral contraceptives can cause falsely low vitamin B(12) levels.

    PubMed

    Gardyn, J; Mittelman, M; Zlotnik, J; Sela, B A; Cohen, A M

    2000-01-01

    Serum vitamin B(12) radioimmunoassays may give falsely low results in patients with folate deficiency, multiple myeloma, megadose of vitamin C and following radioisotope organ scan. We evaluated 10 consecutive healthy women on oral contraceptives (OC) who had falsely low vitamin B(12) levels, as reflected by normal urine methylmalonic acid and plasma homocysteine. After 1-month cessation of OCs, vitamin B(12) returned to the normal range in all women. Transcobalamin I (TCI) blood level was decreased in 60% of patients. OCs may cause temporary low vitamin B(12) blood levels of no clinical significance that can be associated with low TCI levels

  4. Combinatorial de novo design and application of a biomimetic affinity ligand for the purification of human anti-HIV mAb 4E10 from transgenic tobacco.

    PubMed

    Platis, Dimitris; Maltezos, Anastasios; Ma, Julian K-C; Labrou, Nikolaos E

    2009-01-01

    Monoclonal anti-HIV antibody 4E10 (mAb 4E10) is one of the most broadly neutralizing antibodies against HIV, directed against a specific epitope on envelope protein gp41. In the present study, a combinatorial de novo design approach was used for the development of a biomimetic ligand for the affinity purification of mAb 4E10 from tobacco transgenic extract in a single chromatographic step. The biomimetic ligand (4E10lig) was based on a L-Phe/beta-Ala bi-substituted 1,3,5-triazine (Trz) scaffold (beta-Ala-Trz-L-Phe, 4E10lig) which potentially mimics the more pronounced electrostatic and hydrophobic interactions of mAb 4E10-binding sequence determined by screening of a random peptide library. This library was comprised of Escherichia coli cells harboring a plasmid (pFlitrx) engineered to express a fusion protein containing random dodecapeptides that were inserted into the active loop of thioredoxin, which itself was inserted into the dispensable region of the flagellin gene. Adsorption equilibrium studies with this biomimetic ligand and mAb 4E10 determined a dissociation constant (K(D)) of 0.41 +/- 0.05 microM. Molecular modeling studies of the biomimetic ligand revealed that it can potentially occupy the same binding site as the natural binding core peptide epitope. The biomimetic affinity adsorbent was exploited in the development of a facile mAb 4E10 purification protocol, affording mAb 4E10 of high purity (approximately 95%) with good overall yield (60-80%). Analysis of the antibody preparation by SDS-PAGE, enzyme-linked immunosorbent assays (ELISA), and western blot showed that the mAb 4E10 was fully active and free of degraded variants, polyphenols, and alkaloids.

  5. Density functional theory study of the local molecular properties of acetamide derivatives as anti-HIV drugs

    PubMed Central

    Oftadeh, M.; Mahani, N. Madadi; Hamadanian, M.

    2013-01-01

    Accurate quantum chemical computations based on density functional theory (DFT) were performed on the series of 2-(4-(naphthalen-2-yl)-1,2,3-thiadiazol-5-ylthio)-N-acetamide (TTA) derivatives. The local reactivity of the acetamide derivatives as anti-HIV drugs were studied in terms of Fukui functions in the framework of DFT. The results based on the basis set superposition error (BSSE) corrections showed that the mechanism of bond formation between the acetamide derivatives and tyrosine as a biological molecule occurs mainly through nitrogen atoms. The intramolecular interaction energies between the acetamide derivatives and tyrosine were calculated and the nature of the intermolecular interaction was revealed by natural bond orbital charge (NBO) analysis. The results suggest that acetamide derivatives with bromophenyl and nitrophenyl substitutions are the most potent as anti-HIV drugs. PMID:24082898

  6. Causes of Vitamin B12 and Folate Deficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review describes current knowledge of the main causes of vitamin B12 and folate deficiency. The most common explanations for poor B12 status are a low dietary intake of the vitamin (i.e., a low intake of animal-source foods) and malabsorption. Although it has long been known that strict vegetar...

  7. Vitamin B12 in meat and dairy products.

    PubMed

    Gille, Doreen; Schmid, Alexandra

    2015-02-01

    Vitamin B12 is synthesized exclusively by microorganisms; therefore, humans must absorb it from food. Excellent sources of B12 are foods of ruminant origin, so dairy and meat products play an important role in efforts to meet the official daily B12 intake recommendation of 3.0 μg. Concentrations of the vitamin vary within foods of ruminant origin, with the highest concentrations found in offal such as liver and kidney. In comparison, dairy products have much lower quantities of the vitamin. In bovine milk, the B12 concentration is stable with regard to breed, feed, season, and stage of lactation, but in ruminant meat, the amount of B12 can vary based on the feeding and husbandry of the animal as well as the cut of meat chosen and its preparation. Processing of ruminant food, including thermal treatment, usually diminishes the vitamin B12 concentration. This review summarizes the vitamin B12 content of foods and discusses the impact of food processing on vitamin content. The contribution of ruminant food sources to B12 intake is specifically evaluated, with its bioavailability taken into account.

  8. [Pseudothrombotic microangiopathy related to vitamin B(12) deficiency].

    PubMed

    Abourazzak, S; Chaouki, S; Idrissi, M; Atmani, S; Hida, M

    2012-06-01

    Vitamin B(12), or cobalamin, deficiency is often unrecognized because the clinical manifestations are subtle; they are also potentially serious. We report a case of pseudothrombotic microangiopathy related to cobalamin deficiency. Vitamin B(12) deficiency, which is more commonly recognized in the context of malnutrition, should be considered in the context of microangiopathy.

  9. Chemistry and bioactivity of an artificial adenosylpeptide B(12) cofactor.

    PubMed

    Zhou, Kai; Oetterli, René M; Brandl, Helmut; Lyatuu, Fredrick E; Buckel, Wolfgang; Zelder, Felix

    2012-09-24

    Artificial influence: We describe a semi-artificial adenosylpeptide B(12) that behaves as a cofactor in B(12)-dependent enzymatic reactions and demonstrate that the peptide backbone influences its chemical properties and modulates its bioactivity in vitro and in vivo. Inhibition of the growth of L. delbrueckii is demonstrated, thus providing a potentially powerful approach for the development of antibacterial and antiproliferative compounds.

  10. Vegan diet, subnormal vitamin B-12 status and cardiovascular health.

    PubMed

    Woo, Kam S; Kwok, Timothy C Y; Celermajer, David S

    2014-08-19

    Vegetarian diets have been associated with atherosclerosis protection, with healthier atherosclerosis risk profiles, as well as lower prevalence of, and mortality from, ischemic heart disease and stroke. However, there are few data concerning the possible cardiovascular effects of a vegan diet (with no meat, dairy or egg products). Vitamin B-12 deficiency is highly prevalent in vegetarians; this can be partially alleviated by taking dairy/egg products in lact-ovo-vegetarians. However, metabolic vitamin B-12 deficiency is highly prevalent in vegetarians in Australia, Germany, Italy and Austria, and in vegans (80%) in Hong Kong and India, where vegans rarely take vitamin B-12 fortified food or vitamin B-12 supplements. Similar deficiencies exist in northern Chinese rural communities consuming inadequate meat, egg or dairy products due to poverty or dietary habits. Vascular studies have demonstrated impaired arterial endothelial function and increased carotid intima-media thickness as atherosclerosis surrogates in such metabolic vitamin B-12 deficient populations, but not in lactovegetarians in China. Vitamin B-12 supplementation has a favourable impact on these vascular surrogates in Hong Kong vegans and in underprivileged communities in northern rural China. Regular monitoring of vitamin B-12 status is thus potentially beneficial for early detection and treatment of metabolic vitamin B-12 deficiency in vegans, and possibly for prevention of atherosclerosis-related diseases.

  11. 32 CFR 806b.12 - Requesting the Social Security Number.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Requesting the Social Security Number. 806b.12... ADMINISTRATION PRIVACY ACT PROGRAM Collecting Personal Information § 806b.12 Requesting the Social Security Number. When asking an individual for his or her Social Security Number, always give a Privacy...

  12. 32 CFR 806b.12 - Requesting the Social Security Number.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Requesting the Social Security Number. 806b.12... ADMINISTRATION PRIVACY ACT PROGRAM Collecting Personal Information § 806b.12 Requesting the Social Security Number. When asking an individual for his or her Social Security Number, always give a Privacy...

  13. 32 CFR 806b.12 - Requesting the Social Security Number.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Requesting the Social Security Number. 806b.12... ADMINISTRATION PRIVACY ACT PROGRAM Collecting Personal Information § 806b.12 Requesting the Social Security Number. When asking an individual for his or her Social Security Number, always give a Privacy...

  14. 32 CFR 806b.12 - Requesting the Social Security Number.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Requesting the Social Security Number. 806b.12... ADMINISTRATION PRIVACY ACT PROGRAM Collecting Personal Information § 806b.12 Requesting the Social Security Number. When asking an individual for his or her Social Security Number, always give a Privacy...

  15. 32 CFR 806b.12 - Requesting the Social Security Number.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Requesting the Social Security Number. 806b.12... ADMINISTRATION PRIVACY ACT PROGRAM Collecting Personal Information § 806b.12 Requesting the Social Security Number. When asking an individual for his or her Social Security Number, always give a Privacy...

  16. Vegan Diet, Subnormal Vitamin B-12 Status and Cardiovascular Health

    PubMed Central

    Woo, Kam S.; Kwok, Timothy C.Y.; Celermajer, David S.

    2014-01-01

    Vegetarian diets have been associated with atherosclerosis protection, with healthier atherosclerosis risk profiles, as well as lower prevalence of, and mortality from, ischemic heart disease and stroke. However, there are few data concerning the possible cardiovascular effects of a vegan diet (with no meat, dairy or egg products). Vitamin B-12 deficiency is highly prevalent in vegetarians; this can be partially alleviated by taking dairy/egg products in lact-ovo-vegetarians. However, metabolic vitamin B-12 deficiency is highly prevalent in vegetarians in Australia, Germany, Italy and Austria, and in vegans (80%) in Hong Kong and India, where vegans rarely take vitamin B-12 fortified food or vitamin B-12 supplements. Similar deficiencies exist in northern Chinese rural communities consuming inadequate meat, egg or dairy products due to poverty or dietary habits. Vascular studies have demonstrated impaired arterial endothelial function and increased carotid intima-media thickness as atherosclerosis surrogates in such metabolic vitamin B-12 deficient populations, but not in lactovegetarians in China. Vitamin B-12 supplementation has a favourable impact on these vascular surrogates in Hong Kong vegans and in underprivileged communities in northern rural China. Regular monitoring of vitamin B-12 status is thus potentially beneficial for early detection and treatment of metabolic vitamin B-12 deficiency in vegans, and possibly for prevention of atherosclerosis-related diseases. PMID:25195560

  17. Development of water-soluble polyanionic carbosilane dendrimers as novel and highly potent topical anti-HIV-2 microbicides

    NASA Astrophysics Data System (ADS)

    Briz, Verónica; Sepúlveda-Crespo, Daniel; Diniz, Ana Rita; Borrego, Pedro; Rodes, Berta; de La Mata, Francisco Javier; Gómez, Rafael; Taveira, Nuno; Muñoz-Fernández, Mª Ángeles

    2015-08-01

    The development of topical microbicide formulations for vaginal delivery to prevent HIV-2 sexual transmission is urgently needed. Second- and third-generation polyanionic carbosilane dendrimers with a silicon atom core and 16 sulfonate (G2-S16), napthylsulfonate (G2-NS16) and sulphate (G3-Sh16) end-groups have shown potent and broad-spectrum anti-HIV-1 activity. However, their antiviral activity against HIV-2 and mode of action have not been probed. Cytotoxicity, anti-HIV-2, anti-sperm and antimicrobial activities of dendrimers were determined. Analysis of combined effects of triple combinations with tenofovir and raltegravir was performed by using CalcuSyn software. We also assessed the mode of antiviral action on the inhibition of HIV-2 infection through a panel of different in vitro antiviral assays: attachment, internalization in PBMCs, inactivation and cell-based fusion. Vaginal irritation and histological analysis in female BALB/c mice were evaluated. Our results suggest that G2-S16, G2-NS16 and G3-Sh16 exert anti-HIV-2 activity at an early stage of viral replication inactivating the virus, inhibiting cell-to-cell HIV-2 transmission, and blocking the binding of gp120 to CD4, and the HIV-2 entry. Triple combinations with tenofovir and raltegravir increased the anti-HIV-2 activity, consistent with synergistic interactions (CIwt: 0.33-0.66). No vaginal irritation was detected in BALB/c mice after two consecutive applications for 2 days with 3% G2-S16. Our results have clearly shown that G2-S16, G2-NS16 and G3-Sh16 have high potency against HIV-2 infection. The modes of action confirm their multifactorial and non-specific ability, suggesting that these dendrimers deserve further studies as potential candidate microbicides to prevent vaginal/rectal HIV-1/HIV-2 transmission in humans.

  18. A new vinyl selenone-based domino approach to spirocyclopropyl oxindoles endowed with anti-HIV RT activity.

    PubMed

    Palomba, M; Rossi, L; Sancineto, L; Tramontano, E; Corona, A; Bagnoli, L; Santi, C; Pannecouque, C; Tabarrini, O; Marini, F

    2016-02-14

    Herein, we disclose a general and flexible access to spirocyclopropyl oxindoles by a domino Michael/intramolecular nucleophilic substitution pathway with variously substituted vinyl selenones and enolizable oxindoles in aqueous sodium hydroxide solution. The spirocyclopropyl oxindole being a privileged scaffold, some of the synthesized compounds were selected for biological evaluation. Compound showed selective anti-HIV-1 activity thanks to its ability to inhibit the reverse transcriptase.

  19. Anti-HIV seropositivity was related to HBsAg seropositivity among injecting drug users in Taiwan.

    PubMed

    Hsieh, Meng-Hsuan; Hsieh, Ming-Yen; Huang, Chung-Feng; Yeh, Ming-Lun; Wang, Shu-Chi; Yang, Jeng-Fu; Chang, Ko; Lin, Wei-Ru; Lin, Chun-Yu; Chen, Tun-Chieh; Huang, Jee-Fu; Dai, Chia-Yen; Tsai, Jih-Jin; Chuang, Wan-Long; Yu, Ming-Lung

    2016-02-01

    In Taiwan, the number of new cases of human immunodeficiency virus (HIV) infection via drug injection has been increasing since 2003. Due to HIV and hepatitis B virus (HBV) having similar transmission routes, HBV and HIV infections among injecting drug users (IDUs) has become an important public health issue. The aim of this study was explore the prevalence of HBV infection among IDUs with and without HIV infection, and examine whether HIV infection is associated with HBV infection among IDUs in Southern Taiwan. We enrolled 566 IDUs, including 87 anti-HBV positive IDUs and 479 anti-HBV negative IDUs, and also analyzed the results of liver function tests, HBV DNA, anti-HIV, HIV RNA, and CD4 cell count. The results showed that the prevalence of HBV infection among IDUs was 15.4%. The prevalence of hepatitis B surface antigen (HBsAg) was higher among individuals born before 1985 (15.9% vs. 4.0%), but this was not significant. Anti-HIV seropositivity was related to HBsAg seropositivity [odds ratio (OR) = 2.47, 95% confidence interval = 1.26-4.82, p = 0.008). Anti-HCV and anti-HIV were risk factors for abnormal alanine aminotransferase (ALT; OR = 2.11, 95% confidence interval = 1.005-4.42, p = 0.048 and OR = 1.47, 95% confidence interval = 1.02-2.10, p = 0.04, respectively), and HBsAg was not a factor related to abnormal ALT. In conclusion, the prevalence of HBV infection was similar in the general population and in IDUs, and due to anti-HIV seropositivity being significantly related to HBsAg seropositivity, HBV infection among IDUs is still important. We suggest that for IDUs, HBsAg should be monitored closely.

  20. Does an elevated serum vitamin B(12) level mask actual vitamin B(12) deficiency in myeloproliferative disorders?

    PubMed

    Gauchan, Dron; Joshi, Nitin; Gill, Amandeep Singh; Patel, Vishal; Debari, Vincent A; Guron, Gunwant; Maroules, Michael

    2012-08-01

    Elevation of the methylmalonic acid level is a sensitive marker of vitamin B(12) deficiency. Our cross-sectional observational study of 33 patients with myeloproliferative disorders found that 9 patients, 27.27% had occult deficiency despite having normal to elevated serum vitamin B(12) levels. Early detection of vitamin B(12) deficiency by using the methylmalonic acid measurement may prevent significant neurologic and hematologic complications in patients with myeloproliferative disorders. In patients with myeloproliferative disorders, normal to high serum vitamin B(12) concentrations have often been reported. The primary objective of this study was to determine whether normal or elevated serum vitamin B(12) levels in myeloproliferative disorders might actually mask the true underlying vitamin B(12) deficiency in some patients. Thirty-three patients (12 men, 21 women; mean age, 70.55 years [range, 37-90 years]) with polycythemia vera (n = 13), essential thrombocythemia (n = 12), chronic myelogenous leukemia (n = 5), and idiopathic myelofibrosis (IMF) (n = 3) were accrued over a period of 1 year, from March 2009 to February 2010. From all of the subjects, serum vitamin B(12) level, methylmalonic acid level, a basic complete blood cell count panel, and liver and renal function tests were obtained. Normal to elevated serum vitamin B(12) levels were recorded in all the patients. However, elevated serum methylmalonic acid levels were found in 9 (27.27%) patients, with a prevalence of 2 patients with polycythemia vera, 23% in polycythemia vera, 4 patients with essential thrombocythemia, 33.3% in essential thrombocythemia, 1 patient with chronic myelogenous leukemia, 20% in chronic myelogenous leukemia, and 2 patients with idiopathic myelofibrosis, 66.7% in IMF. Our data suggest that 27.27% of the total enrolled patients had occult vitamin B(12) deficiency despite normal to elevated vitamin B(12) levels on regular serum vitamin B(12) testing.

  1. Anti-HIV-1 potency of the CRISPR/Cas9 system insufficient to fully inhibit viral replication.

    PubMed

    Ueda, Shuhei; Ebina, Hirotaka; Kanemura, Yuka; Misawa, Naoko; Koyanagi, Yoshio

    2016-07-01

    The range of genome-editing tools has recently been expanded. In particular, an RNA-guided genome-editing tool, the clustered regularly interspaced short palindromic repeat (CRISPR)-associated 9 (Cas9) system, has many applications for human diseases. In this study, guide RNA (gRNA) to target gag, pol and a long terminal repeat of HIV-1 was designed and used to generate gRNA-expressing lentiviral vectors. An HIV-1-specific gRNA and Cas9 were stably dually transduced into a highly HIV-1-susceptible human T-cell line and the inhibitory ability of the anti-HIV-1 CRISPR/Cas9 lentiviral vector assessed. Although clear inhibition of the early phase of HIV-1 infection was observed, as evaluated by a VSV-G-pseudotyped HIV-1 reporter system, the anti-HIV-1 potency in multiple rounds of wild type (WT) viral replication was insufficient, either because of generation of resistant viruses or overcoming of the activity of the WT virus. Thus, there are potential difficulties that must be addressed when considering anti-HIV-1 treatment with the CRISPR/Cas9 system alone.

  2. Structure and conformational analysis of the anti-HIV AZT 5‧-aminocarbonylphosphonate prodrug using DFT methods

    NASA Astrophysics Data System (ADS)

    Tamara Molina, A.; Alcolea Palafox, M.

    2011-08-01

    A comprehensive theoretical conformational analysis of the anti-HIV AZT 5'-aminocarbonylphosphonate prodrug was carried out, due to this prodrug has noticeable advantage over approved drugs AZT and Nikavir. The whole conformational parameters ( χ, γ, β, α, δ, ɛ, τ, P, νmax) were analysed as well as the NBO Natural atomic charges. The calculations were carried out by means of B3LYP/6-31G ∗∗ and B3LYP/6-311++G(3df,pd) DFT levels of theory with full relaxation of all geometrical parameters. The search located at least 86 stable structures, 6 of which are within a 1 kcal/mol electronic energy range of the global minimum and 11 conformers are within a 1 kcal/mol Gibbs energy range. The global minimum with the 6-311++G(3df,pd) basis set corresponds to the calculated values of the exocyclic torsional angles χ = -121.6°, β = 153.0°, γ = -152.0° and α = -74.1°. The results obtained are in accordance to those found in related anti-HIV nucleoside Analogs. Comparisons of the conformers with those determined in the common anti-HIV drug AZT were carried out. Several correlations and general conclusions were emphasized.

  3. Novel anti-HIV therapeutics targeting chemokine receptors and actin regulatory pathways.

    PubMed

    Spear, Mark; Guo, Jia; Wu, Yuntao

    2013-11-01

    The human immunodeficiency virus-1 (HIV-1) infects helper CD4(+) T cells, and causes CD4(+) T-cell depletion and immunodeficiency. In the past 30 years, significant progress has been made in antiretroviral therapy, and the disease has become manageable. Nevertheless, an effective vaccine is still nowhere in sight, and a cure or a functional cure awaits discovery. Among possible curative therapies, traditional antiretroviral therapy, mostly targeting viral proteins, has been proven ineffective. It is possible that targeting HIV-dependent host cofactors may offer alternatives, both for preventing HIV transmission and for forestalling disease progression. Recently, the actin cytoskeleton and its regulators in blood CD4(+) T cells have emerged as major host cofactors that could be targeted. The novel concept that the cortical actin is a barrier to viral entry and early post-entry migration has led to the nascent model of virus-host interaction at the cortical actin layer. Deciphering the cellular regulatory pathways has manifested exciting prospects for future therapeutics. In this review, we describe the study of HIV interactions with actin cytoskeleton. We also examine potential pharmacological targets that emerge from this interaction. In addition, we briefly discuss several actin pathway-based anti-HIV drugs that are currently in development or testing.

  4. Novel anti-HIV therapeutics targeting chemokine receptors and actin regulatory pathways

    PubMed Central

    Spear, Mark; Guo, Jia; Wu, Yuntao

    2013-01-01

    Summary The human immunodeficiency virus-1 (HIV-1) infects helper CD4+ T cells, and causes CD4+ T-cell depletion and immunodeficiency. In the past 30 years, significant progress has been made in antiretroviral therapy, and the disease has become manageable. Nevertheless, an effective vaccine is still nowhere in sight, and a cure or a functional cure awaits discovery. Among possible curative therapies, traditional antiretroviral therapy, mostly targeting viral proteins, has been proven ineffective. It is possible that targeting HIV-dependent host cofactors may offer alternatives, both for preventing HIV transmission and for forestalling disease progression. Recently, the actin cytoskeleton and its regulators in blood CD4+ T cells have emerged as major host cofactors that could be targeted. The novel concept that the cortical actin is a barrier to viral entry and early post-entry migration has led to the nascent model of virus-host interaction at the cortical actin layer. Deciphering the cellular regulatory pathways has manifested exciting prospects for future therapeutics. In this review, we describe the study of HIV interactions with actin cytoskeleton. We also examine potential pharmacological targets that emerge from this interaction. In addition, we briefly discuss several actin pathway-based anti-HIV drugs that are currently in development or testing. PMID:24117829

  5. Mucosal and systemic anti-HIV immunity controlled by A20 in mouse dendritic cells.

    PubMed

    Hong, Bangxing; Song, Xiao-Tong; Rollins, Lisa; Berry, Lindsey; Huang, Xue F; Chen, Si-Yi

    2011-02-01

    Both mucosal and systemic immune responses are required for preventing or containing HIV transmission and chronic infection. However, currently described vaccination approaches are largely ineffective in inducing both mucosal and systemic responses. In this study, we found that the ubiquitin-editing enzyme A20--an inducible feedback inhibitor of the TNFR, RIG-I, and TLR signaling pathways that broadly controls the maturation, cytokine production, and immunostimulatory potency of DCs--restricted systemically immunized DCs to induce both robust mucosal and systemic HIV-specific cellular and humoral responses. Mechanistic studies revealed that A20 regulated DC production of retinoic acid and proinflammatory cytokines, inhibiting the expression of gut-homing receptors on T and B cells. Furthermore, A20-silenced, hyperactivated DCs exhibited an enhanced homing capacity to draining and gut-associated lymphoid tissues (GALTs) after systemic administration. Thus, this study provides insights into the role of A20 in innate immunity. This work may allow the development of an efficient HIV vaccination strategy that is capable of inducing both robust systemic and mucosal anti-HIV cellular and humoral responses.

  6. Mucosal and systemic anti-HIV immunity controlled by A20 in mouse dendritic cells

    PubMed Central

    Hong, Bangxing; Song, Xiao-Tong; Rollins, Lisa; Berry, Lindsey; Huang, Xue F.; Chen, Si-Yi

    2011-01-01

    Both mucosal and systemic immune responses are required for preventing or containing HIV transmission and chronic infection. However, currently described vaccination approaches are largely ineffective in inducing both mucosal and systemic responses. In this study, we found that the ubiquitin-editing enzyme A20 — an inducible feedback inhibitor of the TNFR, RIG-I, and TLR signaling pathways that broadly controls the maturation, cytokine production, and immunostimulatory potency of DCs — restricted systemically immunized DCs to induce both robust mucosal and systemic HIV-specific cellular and humoral responses. Mechanistic studies revealed that A20 regulated DC production of retinoic acid and proinflammatory cytokines, inhibiting the expression of gut-homing receptors on T and B cells. Furthermore, A20-silenced, hyperactivated DCs exhibited an enhanced homing capacity to draining and gut-associated lymphoid tissues (GALTs) after systemic administration. Thus, this study provides insights into the role of A20 in innate immunity. This work may allow the development of an efficient HIV vaccination strategy that is capable of inducing both robust systemic and mucosal anti-HIV cellular and humoral responses. PMID:21206085

  7. Role for plasmacytoid dendritic cells in anti-HIV innate immunity.

    PubMed

    Müller-Trutwin, Michaela; Hosmalin, Anne

    2005-10-01

    The role of plasmacytoid dendritic cells (pDC) in anti-HIV immunity is mostly represented by the production of type I IFN in response to HIV infection in vitro and in vivo. This production is decreased in HIV-1 infected patients at the time of primary infection and during chronic disease in association with progression of disease. Circulating pDC counts are decreased concomitantly with type I IFN, and both factors correlate inversely overall with viral loads and positively with CD4+ T-cell counts. These parameters might be used in clinical immunology to monitor treatment and as predictive factors of immune control of HIV-1 replication to help decide whether to interrupt antiretroviral treatment. They may be related to control of HIV replication as well as to pathogenesis of infection, perhaps in setting the balance between immunity or tolerance to the virus. A better understanding of these parameters is required while attempts to use IFN-alpha or ligands of Toll-like receptors found on pDC are being made.

  8. Transient swelling behavior and drug delivery from a dissolving film deploying anti-HIV microbicide

    NASA Astrophysics Data System (ADS)

    Tasoglu, Savas; Katz, David F.; Szeri, Andrew J.

    2010-11-01

    Despite more than two decades of HIV vaccine research, there is still no efficacious HIV vaccine. Very recently, a research group has shown that a microbicide gel formulation of antiretroviral drug Tenofovir, significantly inhibits HIV transmission to women [1]. However, there is a widespread agreement that more effective and diverse drug delivery vehicles must be developed. In this setting, there is now great interest in developing different delivery vehicles such as vaginal rings, gels, and films. Here, we develop a model for transient fluid uptake and swelling behavior, and subsequent dissolution and drug deployment from a film containing anti-HIV microbicide. In the model, the polymer structural relaxation via water uptake is assumed to follow first order kinetics. In the case of a film loaded with an osmotically active solute, the kinetic equation is modified to account for the osmotic effect. The transport rate of solvent and solute within the matrix is characterized by a diffusion equation. After the matrix is relaxed to a specified concentration of solvent, lubrication theory and convective-diffusive transport are employed for flow of the liquefied matrix and drug dispersion respectively. [1] Karim, et al., Science, 2010.

  9. Effects of dilution on elastohydrodynamic coating flow of an anti-HIV microbicide vehicle

    NASA Astrophysics Data System (ADS)

    Szeri, Andrew; Park, Su Chan; Tasoglu, Savas; Katz, David F.

    2009-11-01

    Elastohydrodynamic lubrication over soft substrates characterizes the drug delivery of anti-HIV topical microbicides carried in gel vehicles. These gels are under development to prevent HIV transmission into vulnerable vaginal mucosa during intercourse. Their effectiveness depends on completeness and durability of coating, as well as on the active ingredients. Here we investigate the influence of dilution by vaginal fluid on the coating flows that serve to protect the user. The effects of dilution by vaginal fluid simulant are assessed through rheological experiments at variable dilution of the gel vehicle. This involves determination of the way parameters in a Carreau model of a shear-thinning gel are modified by dilution. The changes in coating are determined from a computational model, based on dilution rheology measured in the laboratory. The elastohydrodynamic lubrication model of Szeri, et al. Physics of Fluids (2008) is supplemented with a convective-diffusive transport equation to handle dilution, and solved using a multi-step scheme in a moving domain.

  10. Anti-HIV microRNA expression in a novel Indian cohort

    PubMed Central

    Dey, Rakesh; Soni, Kartik; Saravanan, Shanmugam; Balakrishnan, Pachamuthu; Kumar, Vikram; Boobalan, Jayaseelan; Solomon, Sunil Suhas; Scaria, Vinod; Solomon, Suniti; Brahmachari, Samir K.; Pillai, Beena

    2016-01-01

    HIV-1 replication inside host cells is known to be regulated by various host factors. Host miRNAs, by virtue of its normal functioning, also regulate HIV-1 RNA expression by either directly targeting virus mRNAs or indirectly by regulating host proteins that HIV-1 uses for own replication. Therefore, it is highly possible that with differential miRNA expression, rate of disease progression will vary in HIV-1 infected individuals. In this study we have compared expression of a panel of 13 reported anti-HIV miRNAs in human PBMCs from long term non progressors (LTNPs), regular progressors and rapid progressors. We found that LTNPs have substantial lower expression of miR-382-5p that positively correlates with viral loads. Combinatorial regulation is highly probable in dictating differential disease progression as average expression of miR-382-5p and miR-155-5p can substantially distinguish LTNP individuals from regular progressors. PMID:27320691

  11. Glycosylated enfuvirtide: a long-lasting glycopeptide with potent anti-HIV activity.

    PubMed

    Cheng, Shuihong; Chang, Xuesong; Wang, Yan; Gao, George F; Shao, Yiming; Ma, Liying; Li, Xuebing

    2015-02-12

    Many peptide-based therapeutics have short circulatory half-lives. We report here that the pharmacokinetics of an anti-HIV peptide drug enfuvirtide (ENF) can be dramatically improved by a chemical glycosylation approach. A set of glycosylated ENFs with varying glycosylation sites and glycan structures were synthesized. Among these, a sialic acid-introduced peptide (SL-ENF) demonstrated a 15-fold extended half-life in rats relative to ENF (T1/2: 23.1 vs 1.5 h), and its antiviral potency was comparable to that of ENF (EC50: 2 vs 3 nM). SL-ENF bound to a functional fragment of the HIV fusogenic protein gp41 and formed complexes with high affinity and α-helicity, revealing the mechanism behind its potent antiviral activity. Because it is widely accepted in biology that glycosylation protects proteins from denaturation and proteases, our approach may be useful for the development of novel protein and peptide drugs with enhanced pharmaceutical properties.

  12. Coating flow of an anti-HIV microbicide gel: boundary dilution and yield stress

    NASA Astrophysics Data System (ADS)

    Szeri, Andrew J.; Tasoglu, Savas; Park, Su Chan; Katz, David F.

    2010-11-01

    A recent study has confirmed, for the first time, that a vaginal gel formulation of the antiretroviral drug Tenofovir, when topically applied, significantly inhibits sexual HIV transmission to women [1]. However, the gel for this drug, and anti-HIV microbicide gels in general, have not been designed using an understanding of how gel spreading govern successful drug delivery. Elastohydrodynamic lubrication theory can be applied to model spreading of microbicide gels [2]. Here, we extend our initial analysis: we incorporate a yield stress, and we model the effects of gel dilution due to contact with vaginal fluid produced at the gel-tissue interface. Our model developed in [2] is supplemented with a convective-diffusive transport equation to characterize dilution, and solved using a multi-step scheme in a moving domain. The association between local dilution of gel and rheological properties is obtained experimentally. To model the common yield stress property of gels, we proceed by scaling analysis first. This establishes the conditions for validity of lubrication theory of a shear thinning yield stress fluid. This involves further development of the model in [2], incorporating a biviscosity model.[4pt] [1] Karim, et al., Science, 2010.[0pt] [2] Szeri, et al., Phy. of Fluids, 2008.

  13. Preclinical evaluation of anti-HIV microbicide products: New models and biomarkers.

    PubMed

    Doncel, Gustavo F; Clark, Meredith R

    2010-12-01

    A safe and effective microbicide product designed to prevent sexual transmission of HIV-1 rests on a solid foundation provided by the proper selection and preclinical characterization of both its active pharmaceutical ingredient (API) and formulation. The evaluation of API and formulation physicochemical properties, drug release, specific antiviral activity, cell and tissue toxicity, organ toxicity, pharmacokinetics, and pharmacodynamics and efficacy provides information to understand the product, make go/no go decisions in the critical path of product development and complete a regulatory dossier to file an investigational new drug (IND) with the US Food and Drug Administration. Incorporation of new models, assays and biomarkers has expanded our ability to understand the mechanisms of action underlying microbicide toxicity and efficacy, enabling a more rational selection of drug and formulation candidates. This review presents an overview of the models and endpoints used to comprehensively evaluate an anti-HIV microbicide in preclinical development. This article forms part of a special supplement on presentations covering HIV transmission and microbicides, based on the symposium "Trends in Microbicide Formulations", held on 25 and 26 January 2010, Arlington, VA.

  14. Neutralizing antibodies inhibit HIV-1 infection of plasmacytoid dendritic cells by an FcγRIIa independent mechanism and do not diminish cytokines production.

    PubMed

    Lederle, Alexandre; Su, Bin; Holl, Vincent; Penichon, Julien; Schmidt, Sylvie; Decoville, Thomas; Laumond, Géraldine; Moog, Christiane

    2014-08-18

    Plasmacytoid dendritic cells (pDC) expressing FcγRIIa are antigen-presenting cells able to link innate and adaptive immunity and producing various cytokines and chemokines. Although highly restricted, they are able to replicate HIV-1. We determined the activity of anti-HIV-1 neutralizing antibodies (NAb) and non-neutralizing inhibitory antibodies (NNIAb) on the infection of primary pDC by HIV-1 primary isolates and analyzed cytokines and chemokines production. Neutralization assay was performed with primary pDC in the presence of serial antibodies (Ab) concentrations. In parallel, we measured the release of cytokines and chemokines by ELISA and CBA Flex assay. We found that NAb, but not NNIAb, inhibit HIV-1 replication in pDC. This inhibitory activity was lower than that detected for myeloid dendritic cells (mDC) infection and independent of FcγRIIa expressed on pDC. Despite the complete protection, IFN-α production was detected in the supernatant of pDC treated with NAb VRC01, 4E10, PGT121, 10-1074, 10E8, or polyclonal IgG44 but not with NAb b12. Production of MIP-1α, MIP-1β, IL-6, and TNF-α by pDC was also maintained in the presence of 4E10, b12 and VRC01. These findings suggest that pDC can be protected from HIV-1 infection by both NAb and IFN-α release triggered by the innate immune response during infection.

  15. Characterization of vitamin B12 in Dunaliella salina.

    PubMed

    Kumudha, Anantharajappa; Sarada, Ravi

    2016-01-01

    Vitamin B12 is one of nature's complex metabolite which is industrially produced using certain bacteria. Algae could be an alternative source of vitamin B12 and in this study, vitamin B12 from a halotolerant green alga, Dunaliella salina V-101 was purified and characterized. The extract of Dunaliella was purified by passing through Amberlite XAD-2 and EASI-extract vitamin B12 immunoaffinity column. The total vitamin B12 content in purified sample fractions was 42 ± 2 μg/100 g dry weight as determined by the chemiluminescence method which was almost close to 49 ± 2 μg/100 g dry weight as estimated by microbiological method. Further quantification of total vitamin B12 using gold nanoparticle (AUNPs) based aptamer showed 40 ± 0.8/100 g dry weight. There was a good correlation among all the methods of quantification. Adenosylcobalamin, a form of vitamin B12 which is a cofactor for methylmalonyl CoA mutase was identified by HPLC. Upon quantification, Dunaliella was found to contain 34 ± 4 μg of adenosylcobalamin for 100 g dry biomass. Authenticity of adenosylcobalmin was confirmed by tandem mass spectrometry (MS/MS), selected ion recording (SIR) and multiple reaction monitoring (MRM) studies.

  16. West syndrome due to vitamin B12 deficiency.

    PubMed

    Serin, Hepsen Mine; Kara, Aslıhan Oruçoğlu; Oğuz, Baran

    2015-12-01

    Vitamin B12 is one of the essential vitamins affecting various systems of the body. Vitamin B12 deficiency in infants often produces haematological and neurological deficits including macrocyticanaemia, neurodevelopmental delay or regression, irritability, weakness, hypotonia, ataxia, apathy, tremor andseizures. In this article, we report the case of a six-month-old male patient diagnosed with West syndrome associated with vitamin B12 deficiency. Although the patient had no evidence of macrocytic anemia in complete blood count, we measured the level of vitamin B12 because the patient had hypotonicity and found it to be low. No other problem was found in the other investigations directed to the etiology of West syndrome. He was being exclusively breast-fed and vitamin B12 deficiency was related with nutritional inadequacy of his mother. Vitamin B12 deficiency should be considered in the differential diagnosis of patients presenting with different neurological findings. In addition, vitamin B12 deficiency should be considered as a rare cause in West syndrome which has a heterogeneous etiology.

  17. Different Neurologic Aspects of Nutritional B12 Deficiency in Infancy.

    PubMed

    Yilmaz, Sanem; Serdaroglu, Gul; Tekgul, Hasan; Gokben, Sarenur

    2016-04-01

    The objective of this study is to evaluate neurologic problems caused by nutritional vitamin B12 deficiency in infancy. Twenty-four cases between 2 and 18 months of age with neurologic symptoms and/or signs and diagnosed as nutritional vitamin B12 deficiency were analyzed. The most common symptoms were developmental retardation, afebrile seizures, and involuntary movements. The mean vitamin B12 levels were lower in patients with both neurologic and extraneurologic involvement when compared to those with only neurologic symptoms. All of the cases were treated with vitamin B12. In patients with severe deficiencies, involuntary movements were observed during vitamin B12 treatment using cyanocobalamin form. At the 1-year follow-up, all but 3 patients were considered neurodevelopmentally normal. The 3 patients that did not fully recover, on admission, had the lowest vitamin B12 levels. It is of great importance to prevent, diagnose, and treat vitamin B12 deficiency promptly to prevent the long-term neurologic problems.

  18. Regulation of phytoplankton dynamics by vitamin B12

    NASA Astrophysics Data System (ADS)

    Sañudo-Wilhelmy, S. A.; Gobler, C. J.; Okbamichael, M.; Taylor, G. T.

    2006-02-01

    Despite the biological necessity of vitamin B12 (cobalamin), its importance in phytoplankton ecology has been ignored for nearly three decades. Here we report strong and selective responses of phytoplankton communities to varying low levels (5-87 pM) of dissolved B12 in several coastal embayments. The ecological importance of this vitamin is inferred from observed declines in dissolved B12 levels as field populations of large (>5 μm) phytoplankton increased. In contrast, biomass of small (<5 μm) phytoplankton varied independently of B12 concentrations. These observations were corroborated by field-based nutrient amendment experiments, in which B12 additions stimulated growth of large phytoplankton taxa 6-fold over unamended controls. In contrast, small taxa (<5 μm) were largely unaffected. This study provides the first evidence of vitamin B12's influence on phytoplankton field population dynamics based on direct chemical measurements of cobalamin, and implicates B12 as an important organic regulator of photoautotrophic fertility in marine systems.

  19. Considering the case for vitamin B12 fortification of flour.

    PubMed

    Allen, Lindsay H; Rosenberg, Irwin H; Oakley, Godfrey P; Omenn, Gilbert S

    2010-03-01

    Reasons to fortify flour with vitamin B12 are considered, including the high prevalence of depletion and deficiency of this vitamin that occurs in persons of all ages in resource-poor countries and in the elderly in wealthier countries, and the adverse functional consequences of poor vitamin B12 status. From a global perspective, the main cause of inadequate intake and status is a low intake of animal-source foods; even lacto-ovo vegetarians have lower serum vitamin B12 concentrations than omnivores, and for various reasons many populations have limited consumption of animal-source foods. Infants are vitamin B12-depleted from early infancy if their mothers' vitamin B12 status and intake are poor during pregnancy and lactation. Even in the United States, more than 20% of the elderly have serum vitamin B12 concentrations that indicate depletion, and an additional 6% have deficiency, primarily due to gastric atrophy, which impairs the absorption of the vitamin from food but usually not from supplements or fortified foods. Although the evidence is limited, it shows that fortified flour, consumed as bread, can improve vitamin B12 status. Where vitamin B12 fortification is implemented, the recommendation is to add 20 microg/kg flour, assuming consumption of 75 to 100 g flour per day, to provide 75% to 100% of the Estimated Average Requirement; the amount of the vitamin that can be added is limited by its cost. The effectiveness of this level of addition for improving vitamin B12 status in programs needs to be determined and monitored. In addition, further research should evaluate the bioavailability of the vitamin from fortified flour by elderly people with food cobalamin malabsorption and gastric atrophy.

  20. Regiospecificity of Chlorophenol Reductive Dechlorination by Vitamin B12s

    PubMed Central

    Smith, Mark H.; Woods, Sandra L.

    1994-01-01

    Vitamin B12, reduced by titanium (III) citrate to vitamin B12s, catalyzes the reductive dechlorination of chlorophenols. Reductive dechlorination of pentachlorophenol and of all tetrachlorophenol and trichlorophenol isomers was observed. Reaction of various chlorophenols with vitamin B12 favored reductive dechlorination at positions adjacent to another chlorinated carbon, but chlorines ortho to the hydroxyl group of a phenol were particularly resistant to reductive dechlorination, even if they were also ortho to a chlorine. This resulted in a reductive dechlorination pattern favoring removal of para and meta chlorines, which differs substantially from the pattern exhibited by anaerobic microbial consortia. PMID:16349438

  1. The electronic structure and chemical bonding of vitamin B12

    NASA Astrophysics Data System (ADS)

    Kurmaev, E. Z.; Moewes, A.; Ouyang, L.; Randaccio, L.; Rulis, P.; Ching, W. Y.; Bach, M.; Neumann, M.

    2003-05-01

    The electronic structure and chemical bonding of vitamin B12 (cyanocobalamin) and B12-derivative (methylcobalamin) are studied by means of X-ray emission (XES) and photoelectron (XPS) spectroscopy. The obtained results are compared with ab initio electronic structure calculations using the orthogonalized linear combination of the atomic orbital method (OLCAO). We show that the chemical bonding in vitamin B12 is characterized by the strong Co-C bond and relatively weak axial Co-N bond. It is further confirmed that the Co-C bond in cyanocobalamin is stronger than that of methylcobalamin resulting in their different biological activity.

  2. [Severe vitamin B12 deficiency in infants breastfed by vegans].

    PubMed

    Roed, Casper; Skovby, Flemming; Lund, Allan Meldgaard

    2009-10-19

    Weight loss and reduction of motor skills resulted in paediatric evaluation of a 10-month-old girl and a 12-month-old boy. Both children suffered form anaemia and delayed development due to vitamin B12 deficiency caused by strict maternal vegan diet during pregnancy and nursing. Therapy with cyanocobalamin was instituted with remission of symptoms. Since infants risk irreversible neurologic damage following severe vitamin B12 deficiency, early diagnosis and treatment are mandatory. Vegan and vegetarian women should take vitamin B12 supplementation during the pregnancy and nursing period.

  3. The photochemical mechanism of a B12-dependent photoreceptor protein

    NASA Astrophysics Data System (ADS)

    Kutta, Roger J.; Hardman, Samantha J. O.; Johannissen, Linus O.; Bellina, Bruno; Messiha, Hanan L.; Ortiz-Guerrero, Juan Manuel; Elías-Arnanz, Montserrat; Padmanabhan, S.; Barran, Perdita; Scrutton, Nigel S.; Jones, Alex R.

    2015-08-01

    The coenzyme B12-dependent photoreceptor protein, CarH, is a bacterial transcriptional regulator that controls the biosynthesis of carotenoids in response to light. On binding of coenzyme B12 the monomeric apoprotein forms tetramers in the dark, which bind operator DNA thus blocking transcription. Under illumination the CarH tetramer dissociates, weakening its affinity for DNA and allowing transcription. The mechanism by which this occurs is unknown. Here we describe the photochemistry in CarH that ultimately triggers tetramer dissociation; it proceeds via a cob(III)alamin intermediate, which then forms a stable adduct with the protein. This pathway is without precedent and our data suggest it is independent of the radical chemistry common to both coenzyme B12 enzymology and its known photochemistry. It provides a mechanistic foundation for the emerging field of B12 photobiology and will serve to inform the development of a new class of optogenetic tool for the control of gene expression.

  4. [Vitamin-B12-dependent methylmalonic acidemia in twins].

    PubMed

    Karsten, J; Hansen, H G; Heuer, R; Wulff, U C; Kneer, J

    1983-05-01

    The tendency towards metabolic acidosis developing during simple infections lead to the detection of hyperglycinemia which was shown to be caused by the rare inborn error of metabolism, which was shown to be a methylmalonic acidemia, in identical twins. Under a protein restricted diet and vitamin-B12-injections once a week, all clinical symptoms disappeared so that vitamin-B12-dependency became evident. Under this therapeutic regimen methylmalonic aciduria was well under control.

  5. Vitamin B12 absorption capacity in healthy children

    SciTech Connect

    Hjelt, K.; Krasilnikoff, P.A.

    1986-03-01

    B12 absorption was investigated in 47 healthy children aged 7 months to 15.8 years (median 4.9 years). The patients had either recovered from giardiasis, the post-gastroenteritis syndrome, or had celiac disease in remission (treated with a gluten-free diet). The B12 absorption was measured by a double-isotope technique using /sup 57/CoB12 and /sup 51/CrCl/sub 3/, the latter being the inabsorbable marker. The radiation dose was minimal. The results were presented as fractional absorption of B12 (FAB12). Within the different age groups, the absorption test was performed by means of the following oral amounts of B12: 0- less than 1 year, 0.5 microgram; 1-3 years: 1.7 micrograms, 4-6 years, 2.5 micrograms; 7-10 years; 3.3 micrograms; and 11-15 years, 4.5 micrograms. When using these oral amounts of B12, the medians (and ranges) of FAB12 were found to be: 1-3 years (n = 18), 37% (16-80%); 4-6 years (n = 10), 27% (19-40%); 7-10 years (n = 9), 32% (21-44%); and 11-15 years (n = 8), 27% (19-59%). The FAB12 in two children aged 7 and 11 months was 31% and 32%, respectively. These results may be interpretated as reference values for B12 absorption in children. Further absorption tests were performed in seven children representing the four age groups from 1 to 15 years. When a high oral amount of B12 was given (i.e., three times the saturation dose), the FAB12 ranged from 0 to 20% (median 9%), whereas a low amount (i.e., one-ninth of the saturation dose) produced fractional absorptions from 65 to 82% (median 74%).

  6. How prevalent is vitamin B(12) deficiency among vegetarians?

    PubMed

    Pawlak, Roman; Parrott, Scott James; Raj, Sudha; Cullum-Dugan, Diana; Lucus, Debbie

    2013-02-01

    Vegetarians are at risk for vitamin B(12) (B12) deficiency due to suboptimal intake. The goal of the present literature review was to assess the rate of B12 depletion and deficiency among vegetarians and vegans. Using a PubMed search to identify relevant publications, 18 articles were found that reported B12 deficiency rates from studies that identified deficiency by measuring methylmalonic acid, holo-transcobalamin II, or both. The deficiency rates reported for specific populations were as follows: 62% among pregnant women, between 25% and almost 86% among children, 21-41% among adolescents, and 11-90% among the elderly. Higher rates of deficiency were reported among vegans compared with vegetarians and among individuals who had adhered to a vegetarian diet since birth compared with those who had adopted such a diet later in life. The main finding of this review is that vegetarians develop B12 depletion or deficiency regardless of demographic characteristics, place of residency, age, or type of vegetarian diet. Vegetarians should thus take preventive measures to ensure adequate intake of this vitamin, including regular consumption of supplements containing B12.

  7. Role of nucleoside diphosphate kinase in the activation of anti-HIV nucleoside analogs.

    PubMed

    Schneider, B; Sarfati, R; Deville-Bonne, D; Véron, M

    2000-06-01

    Nucleoside analogs are currently used in antiretrovirus therapies. The best known example is AZT one of the first drug to be used for the treatment of AIDS. However, only the triphosphate derivatives of these compounds act as substrates of the viral reverse transcriptase. Since they do not enter cells, nucleoside analogs are administered and phosphorylated by cellular kinases. The last step in this phosphorylation pathway is catalyzed by nucleoside diphosphate (NDP) kinase. The incorporation of the nucleoside triphosphates into nascent viral DNA chain results in termination of the elongation process. We have performed kinetics studies of the phosphorylation reaction by NDP kinase of dideoxynucleoside diphosphates such as 2',3'-dideoxy-3'-azidothymidine diphosphate (AZT-DP) and 2',3'-dideoxy-2',3'-didehydrothymidine diphosphate (d4T-DP). We show that the catalytic efficiency is strongly decreased and, therefore, that the reaction step catalyzed by NDP kinase constitutes a bottleneck in the processing pathway of anti-HIV compounds. In addition, the affinity of the analogs in the absence of catalysis was determined using a catalytically inactive NDP kinase mutant, showing a reduction of affinity by a factor of 2 to 30, depending on the analog. The structure of NDP kinase provides a structural explanation for these results. Indeed, all nucleoside analogs acting as chain terminators must lack a 3'-OH in the nucleotide deoxyribose. Unfortunately, this same substitution is detrimental for their capacity to be phosphorylated by NDP kinase. This defines the framework for the design of new nucleoside analogs with increased efficiency in antiretroviral therapies.

  8. Precise engineering of dapivirine-loaded nanoparticles for the development of anti-HIV vaginal microbicides.

    PubMed

    das Neves, José; Sarmento, Bruno

    2015-05-01

    Polymeric nanoparticles (NPs) have the potential to provide effective and safe delivery of antiretroviral drugs in the context of prophylactic anti-HIV vaginal microbicides. Dapivirine-loaded poly(d,l-lactic-co-glycolic acid) (PLGA) NPs were produced by an emulsion-solvent evaporation method, optimized for colloidal properties using a 3-factor, 3-level Box-Behnken experimental design, and characterized for drug loading, production yield, morphology, thermal behavior, drug release, in vitro cellular uptake, cytotoxicity and pro-inflammatory potential. Also, drug permeability/membrane retention in well-established HEC-1-A and CaSki cell monolayer models as mediated by NPs was assessed in the absence or presence of mucin. Box-Behnken design allowed optimizing monodisperse 170nm drug-loaded NPs. Drug release experiments showed an initial burst effect up to 4h, followed by sustained 24h release at pH 4.2 and 7.4. NPs were readily taken up by different genital and macrophage cell lines as assessed by fluorescence microscopy. Drug-loaded NPs presented lower or at least similar cytotoxicity as compared to the free drug, with up to around one-log increase in half-maximal cytotoxic concentration values. In all cases, no relevant changes in cell pro-inflammatory cytokine/chemokine production were observed. Dapivirine transport across cell monolayers was significantly decreased when mucin was present at the donor side with either NPs or the free drug, thus evidencing the influence of this natural glycoprotein in membrane permeability. Moreover, drug retention in cell monolayers was significantly higher for NPs in comparison with the free drug. Overall, obtained dapivirine-loaded PLGA NPs possess interesting technological and biological features that may contribute to their use as novel safe and effective vaginal microbicides.

  9. Use of mutated self-cleaving 2A peptides as a molecular rheostat to direct simultaneous formation of membrane and secreted anti-HIV immunoglobulins.

    PubMed

    Yu, Kenneth K; Aguilar, Kiefer; Tsai, Jonathan; Galimidi, Rachel; Gnanapragasam, Priyanthi; Yang, Lili; Baltimore, David

    2012-01-01

    In nature, B cells produce surface immunoglobulin and secreted antibody from the same immunoglobulin gene via alternative splicing of the pre-messenger RNA. Here we present a novel system for genetically programming B cells to direct the simultaneous formation of membrane-bound and secreted immunoglobulins that we term a "Molecular Rheostat", based on the use of mutated "self-cleaving" 2A peptides. The Molecular Rheostat is designed so that the ratio of secreted to membrane-bound immunoglobulins can be controlled by selecting appropriate mutations in the 2A peptide. Lentiviral transgenesis of Molecular Rheostat constructs into B cell lines enables the simultaneous expression of functional b12-based IgM-like BCRs that signal to the cells and mediate the secretion of b12 IgG broadly neutralizing antibodies that can bind and neutralize HIV-1 pseudovirus. We show that these b12-based Molecular Rheostat constructs promote the maturation of EU12 B cells in an in vitro model of B lymphopoiesis. The Molecular Rheostat offers a novel tool for genetically manipulating B cell specificity for B-cell based gene therapy.

  10. Monoclonal And Single Domain Antibodies Targeting β-Integrin Subunits Block Sexual Transmission of HIV-1 in in vitro and in vivo Model Systems

    PubMed Central

    Guedon, Janet Tai; Luo, Kun; Zhang, Hong; Markham, Richard B.

    2015-01-01

    Background Poor adherence to prevention regimens for gel-based anti-HIV-1 microbicides has been a major obstacle to more effective pre-exposure prophylaxis. Concern persists that the antiretroviral drug containing microbicides might promote development of antiretroviral resistance. Methods Using in vitro transwell systems and a humanized mouse model of HIV-1 sexual transmission, we examined, as candidate microbicides, antibodies targeting the heterodimeric leukocyte function associated antigen 1 (LFA-1), a non-virally encoded protein acquired by the virus that also plays a critical role cell movement across endothelial and epithelial barriers. LFA-1 specific single domain variable regions from alpaca heavy-chain only antibodies (VHH) were identified and evaluated for their ability to inhibit HIV-1 transmission in the in vitro transwell system. Results Monoclonal antibodies targeting the CD11a and CD18 components of LFA-1 significantly reduced cell-free and cell-associated HIV-1 transmission in the in vitro transwell culture system and prevented virus transmission in the humanized mouse model of vaginal transmission. The broadly neutralizing monoclonal antibody b12 was unable to block transmission of cell-free virus. CD11a-specific VHH were isolated and expressed and the purified variable region protein domains reduced in vitro transepithelial transmission with an efficacy comparable to that of the CD11a monoclonal antibody. Conclusions Targeting integrins acquired by HIV-1 during budding and which are critical to interactions between epithelial cells and lymphocytes can reduce viral movement across epithelial barriers and prevent transmission in a humanized mouse model of sexual transmission. VHH capable of being produced by transformed bacteria can significantly reduce transepithelial virus transmission in in vitro model systems. PMID:25828964

  11. Llama antibody fragments recognizing various epitopes of the CD4bs neutralize a broad range of HIV-1 subtypes A, B and C.

    PubMed

    Strokappe, Nika; Szynol, Agnieszka; Aasa-Chapman, Marlèn; Gorlani, Andrea; Forsman Quigley, Anna; Hulsik, David Lutje; Chen, Lei; Weiss, Robin; de Haard, Hans; Verrips, Theo

    2012-01-01

    Many of the neutralising antibodies, isolated to date, display limited activities against the globally most prevalent HIV-1 subtypes A and C. Therefore, those subtypes are considered to be an important target for antibody-based therapy. Variable domains of llama heavy chain antibodies (VHH) have some superior properties compared with classical antibodies. Therefore we describe the application of trimeric forms of envelope proteins (Env), derived from HIV-1 of subtype A and B/C, for a prolonged immunization of two llamas. A panel of VHH, which interfere with CD4 binding to HIV-1 Env were selected with use of panning. The results of binding and competition assays to various Env, including a variant with a stabilized CD4-binding state (gp120(Ds2)), cross-competition experiments, maturation analysis and neutralisation assays, enabled us to classify the selected VHH into three groups. The VHH of group I were efficient mainly against viruses of subtype A, C and B'/C. The VHH of group II resemble the broadly neutralising antibody (bnmAb) b12, neutralizing mainly subtype B and C viruses, however some had a broader neutralisation profile. A representative of the third group, 2E7, had an even higher neutralization breadth, neutralizing 21 out of the 26 tested strains belonging to the A, A/G, B, B/C and C subtypes. To evaluate the contribution of certain amino acids to the potency of the VHH a small set of the mutants were constructed. Surprisingly this yielded one mutant with slightly improved neutralisation potency against 92UG37.A9 (subtype A) and 96ZM651.02 (subtype C). These findings and the well-known stability of VHH indicate the potential application of these VHH as anti-HIV-1 microbicides.

  12. Is wetter better? An evaluation of over-the-counter personal lubricants for safety and anti-HIV-1 activity.

    PubMed

    Dezzutti, Charlene S; Brown, Elizabeth R; Moncla, Bernard; Russo, Julie; Cost, Marilyn; Wang, Lin; Uranker, Kevin; Kunjara Na Ayudhya, Ratiya P; Pryke, Kara; Pickett, Jim; Leblanc, Marc-André; Rohan, Lisa C

    2012-01-01

    Because lubricants may decrease trauma during coitus, it is hypothesized that they could aid in the prevention of HIV acquisition. Therefore, safety and anti-HIV-1 activity of over-the-counter (OTC) aqueous- (n = 10), lipid- (n = 2), and silicone-based (n = 2) products were tested. The rheological properties of the lipid-based lubricants precluded testing with the exception of explant safety testing. Six aqueous-based gels were hyperosmolar, two were nearly iso-osmolar, and two were hypo-osmolar. Evaluation of the panel of products showed Gynol II (a spermicidal gel containing 2% nonoxynol-9), KY Jelly, and Replens were toxic to Lactobacillus. Two nearly iso-osmolar aqueous- and both silicone-based gels were not toxic toward epithelial cell lines or ectocervical or colorectal explant tissues. Hyperosmolar lubricants demonstrated reduction of tissue viability and epithelial fracture/sloughing while the nearly iso-osmolar and silicon-based lubricants showed no significant changes in tissue viability or epithelial modifications. While most of the lubricants had no measurable anti-HIV-1 activity, three lubricants which retained cell viability did demonstrate modest anti-HIV-1 activity in vitro. To determine if this would result in protection of mucosal tissue or conversely determine if the epithelial damage associated with the hyperosmolar lubricants increased HIV-1 infection ex vivo, ectocervical tissue was exposed to selected lubricants and then challenged with HIV-1. None of the lubricants that had a moderate to high therapeutic index protected the mucosal tissue. These results show hyperosmolar lubricant gels were associated with cellular toxicity and epithelial damage while showing no anti-viral activity. The two iso-osmolar lubricants, Good Clean Love and PRÉ, and both silicone-based lubricants, Female Condom 2 lubricant and Wet Platinum, were the safest in our testing algorithm.

  13. Is Wetter Better? An Evaluation of Over-the-Counter Personal Lubricants for Safety and Anti-HIV-1 Activity

    PubMed Central

    Dezzutti, Charlene S.; Brown, Elizabeth R.; Moncla, Bernard; Russo, Julie; Cost, Marilyn; Wang, Lin; Uranker, Kevin; Kunjara Na Ayudhya, Ratiya P.; Pryke, Kara; Pickett, Jim; LeBlanc, Marc-André; Rohan, Lisa C.

    2012-01-01

    Because lubricants may decrease trauma during coitus, it is hypothesized that they could aid in the prevention of HIV acquisition. Therefore, safety and anti-HIV-1 activity of over-the-counter (OTC) aqueous- (n = 10), lipid- (n = 2), and silicone-based (n = 2) products were tested. The rheological properties of the lipid-based lubricants precluded testing with the exception of explant safety testing. Six aqueous-based gels were hyperosmolar, two were nearly iso-osmolar, and two were hypo-osmolar. Evaluation of the panel of products showed Gynol II (a spermicidal gel containing 2% nonoxynol-9), KY Jelly, and Replens were toxic to Lactobacillus. Two nearly iso-osmolar aqueous- and both silicone-based gels were not toxic toward epithelial cell lines or ectocervical or colorectal explant tissues. Hyperosmolar lubricants demonstrated reduction of tissue viability and epithelial fracture/sloughing while the nearly iso-osmolar and silicon-based lubricants showed no significant changes in tissue viability or epithelial modifications. While most of the lubricants had no measurable anti-HIV-1 activity, three lubricants which retained cell viability did demonstrate modest anti-HIV-1 activity in vitro. To determine if this would result in protection of mucosal tissue or conversely determine if the epithelial damage associated with the hyperosmolar lubricants increased HIV-1 infection ex vivo, ectocervical tissue was exposed to selected lubricants and then challenged with HIV-1. None of the lubricants that had a moderate to high therapeutic index protected the mucosal tissue. These results show hyperosmolar lubricant gels were associated with cellular toxicity and epithelial damage while showing no anti-viral activity. The two iso-osmolar lubricants, Good Clean Love and PRÉ, and both silicone-based lubricants, Female Condom 2 lubricant and Wet Platinum, were the safest in our testing algorithm. PMID:23144863

  14. Synthesis of single- and double-chain fluorocarbon and hydrocarbon galactosyl amphiphiles and their anti-HIV-1 activity.

    PubMed

    Faroux-Corlay, B; Clary, L; Gadras, C; Hammache, D; Greiner, J; Santaella, C; Aubertin, A M; Vierling, P; Fantini, J

    2000-07-24

    Galactosylceramide (GalCer) is an alternative receptor allowing HIV-1 entry into CD4(-)/GalCer(+) cells. This glycosphingolipid recognizes the V3 loop of HIV gp120, which plays a key role in the fusion of the HIV envelope and cellular membrane. To inhibit HIV uptake and infection, we designed and synthesized analogs of GalCer. These amphiphiles and bolaamphiphiles consist of single and double hydrocarbon and/or fluorocarbon chain beta-linked to galactose and galactosamine. They derive from serine (GalSer), cysteine (GalCys), and ethanolamine (GalAE). The anti-HIV activity and cytotoxicity of these galactolipids were evaluated in vitro on CEM-SS (a CD4(+) cell line), HT-29, a CD4(-) cell line expressing high levels of GalCer receptor, and/or HT29 genetically modified to express CD4. GalSer and GalAE derivatives, tested in aqueous medium or as part of liposome preparation, showed moderate anti-HIV-1 activities (IC50 in the 20-220 microM range), whereas none of the GalCys derivatives was found to be active. Moreover, only some of these anti-HIV active analogs inhibited the binding of [3H]suramin (a polysulfonyl compound which displays a high affinity for the V3 loop) to SPC3, a synthetic peptide which contains the conserved GPGRAF region of the V3 loop. Our results most likely indicate that the neutralization of the virion through masking of this conserved V3 loop region is not the only mechanism involved in the HIV-1 antiviral activity of our GalCer analogs.

  15. Docking of anti-HIV-1 oxoquinoline-acylhydrazone derivatives as potential HSV-1 DNA polymerase inhibitors

    NASA Astrophysics Data System (ADS)

    Yoneda, Julliane Diniz; Albuquerque, Magaly Girão; Leal, Kátia Zaccur; Santos, Fernanda da Costa; Batalha, Pedro Netto; Brozeguini, Leonardo; Seidl, Peter R.; de Alencastro, Ricardo Bicca; Cunha, Anna Cláudia; de Souza, Maria Cecília B. V.; Ferreira, Vitor F.; Giongo, Viveca A.; Cirne-Santos, Cláudio; Paixão, Izabel C. P.

    2014-09-01

    Although there are many antiviral drugs available for the treatment of herpes simplex virus (HSV) infections, still the synthesis of new anti-HSV candidates is an important strategy to be pursued, due to the emergency of resistant HSV strains mainly in human immunodeficiency virus (HIV) co-infected patients. Some 1,4-dihydro-4-oxoquinolines, such as PNU-183792 (1), show a broad spectrum antiviral activity against human herpes viruses, inhibiting the viral DNA polymerase (POL) without affecting the human POLs. Thus, on an ongoing antiviral research project, our group has synthesized ribonucleosides containing the 1,4-dihydro-4-oxoquinoline (quinolone) heterocyclic moiety, such as the 6-Cl derivative (2), which is a dual antiviral agent (HSV-1 and HIV-1). Molecular dynamics simulations of the complexes of 1 and 2 with the HSV-1 POL suggest that structural modifications of 2 should increase its experimental anti-HSV-1 activity, since its ribosyl and carboxyl groups are highly hydrophilic to interact with a hydrophobic pocket of this enzyme. Therefore, in this work, comparative molecular docking simulations of 1 and three new synthesized oxoquinoline-acylhydrazone HIV-1 inhibitors (3-5), which do not contain those hydrophilic groups, were carried out, in order to access these modifications in the proposition of new potential anti-HSV-1 agents, but maintaining the anti-HIV-1 activity. Among the docked compounds, the oxoquinoline-acylhydrazone 3 is the best candidate for an anti-HSV-1 agent, and, in addition, it showed anti-HIV-1 activity (EC50 = 3.4 ± 0.3 μM). Compounds 2 and 3 were used as templates in the design of four new oxoquinoline-acylhydrazones (6-9) as potential anti-HSV-1 agents to increase the antiviral activity of 2. Among the docked compounds, oxoquinoline-acylhydrazone 7 was selected as the best candidate for further development of dual anti-HIV/HSV activity.

  16. Natural Products as Anti-HIV Agents and Role in HIV-Associated Neurocognitive Disorders (HAND): A Brief Overview

    PubMed Central

    Kurapati, Kesava Rao V.; Atluri, Venkata S.; Samikkannu, Thangavel; Garcia, Gabriella; Nair, Madhavan P. N.

    2016-01-01

    As the threat of Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) persists to rise, effective drug treatments are required to treat the infected people. Even though combination antiretroviral therapy (cART) provides stable viral suppression, it is not devoid of undesirable side effects, especially in persons undergoing long-term treatment. The present therapy finds its limitations in the emergence of multidrug resistance and accordingly finding new drugs and novel targets is the need of the hour to treat the infected persons and further to attack HIV reservoirs in the body like brain, lymph nodes to achieve the ultimate goal of complete eradication of HIV and AIDS. Natural products such as plant-originated compounds and plant extracts have enormous potential to become drug leads with anti-HIV and neuroprotective activity. Accordingly, many research groups are exploring the biodiversity of the plant kingdom to find new and better anti-HIV drugs with novel mechanisms of action and for HIV-associated neurocognitive disorders (HAND). The basic challenge that still persists is to develop viral replication-targeted therapy using novel anti-HIV compounds with new mode of action, accepted toxicity and less resistance profile. Against this backdrop, the World Health Organization (WHO) suggested the need to evaluate ethno-medicines for the management of HIV/AIDS. Consequently, there is need to evaluate traditional medicine, particularly medicinal plants and other natural products that may yield effective and affordable therapeutic agents. Although there are a good number of reports on traditional uses of plants to treat various diseases, knowledge of herbal remedies used to manage HIV/AIDS and HAND are scanty, vague and not well documented. In this review, plant substances showing a promising action that is anti-HIV and HAND will be explored along with what they interact. Since some plant substances are also known to modulate several cellular

  17. [Synthesis, properties and anti-HIV activity of novel lipophilic 3'-azido-3'-deoxythymidine conjugates containing functional phosphoric linkages].

    PubMed

    Shastina, N S; Mal'tseva, T Iu; D'iakova, L N; Lobach, O A; Chataeva, M S; Nosik, D N; Shvetz, V I

    2013-01-01

    One of the approaches to enhance bioavailability of nucleoside reverse transcriptase HIV inhibitors consists in design of their prodrugs based on 1,3-diacylglycerols, which may simulate nature lipids metabolic pathways promoting the improvement of drug delivery to the target cells. Glycerolipidic AZT conjugates with different functional phosphoric centers were synthesized by H-phosphonate technique in the present work. Study of prepared prodrugs sensibility to the chemical and enzymatic hydrolysis (in buffer solution and under the influence of pancreatic lipase) and also study of their anti-HIV activity on the T-lymphoid human MT-4 cells in regarding to virus HIV-1(899A) strain were carried out.

  18. Catalysis of Methyl Group Transfers Involving Tetrahydrofolate and B12

    PubMed Central

    Ragsdale, Stephen W.

    2011-01-01

    This review focuses on the reaction mechanism of enzymes that use B12 and tetrahydrofolate (THF) to catalyze methyl group transfers. It also covers the related reactions that use B12 and tetrahydromethanopterin (THMPT), which is a THF analog used by archaea. In the past decade, our understanding of the mechanisms of these enzymes has increased greatly because the crystal structures for three classes of B12-dependent methyltransferases have become available and because biophysical and kinetic studies have elucidated the intermediates involved in catalysis. These steps include binding of the cofactors and substrates, activation of the methyl donors and acceptors, the methyl transfer reaction itself, and product dissociation. Activation of the methyl donor in one class of methyltransferases is achieved by an unexpected proton transfer mechanism. The cobalt (Co) ion within the B12 macrocycle must be in the Co(I) oxidation state to serve as a nucleophile in the methyl transfer reaction. Recent studies have uncovered important principles that control how this highly reducing active state of B12 is generated and maintained. PMID:18804699

  19. Isolation and analysis of vitamin B12 from plant samples.

    PubMed

    Nakos, M; Pepelanova, I; Beutel, S; Krings, U; Berger, R G; Scheper, T

    2017-02-01

    Based on increased demands of strict vegetarians, an investigation of vitamin B12 content in plant sources, was carried out. The vitamin B12 concentration was determined by RP-HPLC with UV detection, after prior matrix isolation by immunoaffinity chromatography (IAC). Vitamin B12 was extracted in the presence of sodium cyanide, to transform all forms of cobalamin into cyanocobalamin. Diode array detector was used to monitor vitamin B12, after its chromatographic separation under gradient elution with a mobile phase consisting of acetonitrile and trifluoroacetic acid 0.025% (w/v). The method demonstrated excellent linearity with a limit of detection 0.004μg/ml. The method precision was evaluated for plant samples and it was below 0.7% (n=6). Significant amounts of vitamin B12 in plants were detected in Hippophae rhamnoides (37μg/100g dry weight), in Elymus (26μg/100g dry weight) and in Inula helenium (11μg/100g dry weight).

  20. Effect of bile on vitamin B12 absorption.

    PubMed Central

    Teo, N H; Scott, J M; Neale, G; Weir, D G

    1980-01-01

    The standard double-isotope Schilling test was used to study vitamin B12 absorption in seven patients with obstructive jaundice and 10 with T-tube bile duct drainage after cholecystectomy and bile duct exploration. In three and five of these patients respectively absorption was impaired. In the second group six patients were restudied after removal of the T tube, and in each case absorption was improved. Similar results were obtained after bile duct ligation in rats. Bile exclusion produced a 50-60% reduction in renal and hepatic uptake of vitamin B12 from the intestinal lumen. The malabsorption was corrected by replacing bile. These studies suggest that bile plays a part in the normal absorption of vitamin B12. PMID:7427470

  1. Oral contraceptives: effect of folate and vitamin B12 metabolism.

    PubMed Central

    Shojania, A. M.

    1982-01-01

    Women who use oral contraceptives have impaired folate metabolism as shown by slightly but significantly lower levels of folate in the serum and the erythrocytes and an increased urinary excretion of formiminoglutamic acid. The vitamin B12 level in their serum is also significantly lower than that of control groups. However, there is no evidence of tissue depletion of vitamin B12 associated with the use of oral contraceptives. The causes and clinical significance of the impairment of folate and vitamin B12 metabolism in these women is discussed in this review of the literature. Clinicians are advised to ensure that women who shop taking "the pill" because they wish to conceive have adequate folate stores before becoming pregnant. PMID:7037144

  2. Infantile tremor syndrome: Role of Vitamin B12 revisited

    PubMed Central

    Gupta, Rajesh; Mandliya, Jagdish; Sonker, Pavan; Patil, Vandana; Agrawal, Manish; Pathak, Ashish

    2016-01-01

    Objective: To study the role of Vitamin B12 as an etiological factor in patients of infantile tremor syndrome (ITS). Methods: Twelve consecutive admissions of children diagnosed clinically as ITS were assessed. Assessment was done using a predefined pro forma to document patient demographic factors, general examination, systemic examination as well as relevant hematological and biochemical investigations. Results: Out of the 12 cases of ITS, 6 were males and 6 were females. Two cases had serum B12 levels below reference values, five had levels in low normal range, and remaining five had normal values. Conclusions: Role of Vitamin B12 deficiency as an etiological factor in the patients of ITS is inconclusive. PMID:28217151

  3. Methylmalonic acidemia controlled with oral administration of vitamin B12.

    PubMed Central

    Gordon, B. A.; Carson, R. A.

    1976-01-01

    A 3-month-old male infant had two episodes of fever, projectile vomiting, dehydration, generalized fine tremors and gross metabloic ketoacidosis. Methylmalonic acid was found in high concentration in both serum and urine, although the concentration of serum vitamin B12 was normal. A therapeutic trial of vitamin B12, administered parenterally, reduced greatly the methylmalonic aciduria. The patient has since been given vitamin B12 supplements continuously, initially 1 mg intramuscularly every other day, then 15 mg/d orally, and the protein in his diet was subsequently restricted. The most effected control of the methylmalonic aciduria was achieved with the combined regimen of oral vitamin therapy and dietary protein restriction. His physical and intellectual development have progressed normally and he has survived several acute respiratory tract infections without recurrence of metabolic acidosis. PMID:953884

  4. Localization of vitamin B12 binding in Euglena gracilis.

    PubMed

    Houde, M; Sarhan, F

    1990-03-01

    Different fractionation procedures were used to determine the location of vitamin B12 binding sites in Euglena gracilis. Using uptake measurements, cell fractionation, and light and electron microscopy, the cuticle of the cell was found to be the fraction containing the majority of B12 binding sites. The apparent distribution of vitamin binding sites differed according to the cell lysis method used. The cuticle fraction was responsible for the binding of 80% of the vitamin taken up by the cell during both the rapid and the slow phase of uptake. These results suggest that vitamin B12 binding is regulated, in part, at the cuticle level, and support our previous conclusion that the secondary phase of uptake represents the synthesis of new receptor sites and not the unloading of vitamin inside the cell.

  5. Visualising molecular juggling within a B12-dependent methyltransferase complex

    PubMed Central

    Kung, Yan; Ando, Nozomi; Doukov, Tzanko I.; Blasiak, Leah C.; Bender, Güneş; Seravalli, Javier; Ragsdale, Stephen W.; Drennan, Catherine L.

    2012-01-01

    Derivatives of vitamin B12 are used in methyl group transfer in biological processes as diverse as methionine synthesis in humans and CO2 fixation in acetogenic bacteria1–3. This seemingly straightforward reaction requires large, multimodular enzyme complexes that adopt multiple conformations to alternately activate, protect, and perform catalysis on the reactive B12 cofactor. Crystal structures determined thus far have provided structural information for only fragments of these complexes4–12, inspiring speculation regarding the overall protein assembly and conformational movements inherent to activity. Here we present X-ray crystal structures of a complete ~220 kDa complex that contains all enzymes responsible for B12-dependent methyltransfer, namely the corrinoid iron-sulfur protein (CFeSP) and its methyltransferase (MeTr) from the model acetogen Moorella thermoacetica. These structures provide the first three-dimensional depiction of all protein modules required for the activation, protection, and catalytic steps of B12-dependent methyltransfer. In addition, the structures capture B12 at multiple locations between its “resting” and catalytic positions, allowing visualisation of the dramatic protein rearrangements that enable methyltransfer and identification of the trajectory for B12 movement within the large enzyme scaffold. The structures are also presented alongside in crystallo UV-vis spectroscopic data, which confirm enzymatic activity within crystals and demonstrate the largest known conformational movements of proteins in a crystalline state. Taken together, this work provides a model for the molecular juggling that accompanies turnover and helps explain why such an elaborate protein framework is required for such a simple, yet biologically essential reaction. PMID:22419154

  6. Vitamin B12 deficit and development of geriatric syndromes.

    PubMed

    Ocampo Chaparro, José Mauricio

    2013-01-01

    Vitamin B12 deficiency or cyanocobalamin is a common condition in the elderly. It is repeatedly overlooked due to multiple clinical manifestations that can affect the blood, neurological, gastrointestinal, and cardiovascular systems, skin and mucous membranes. The various presentations of vitamin B12 deficiency are related to the development of geriatric syndromes like frailty, falls, cognitive impairment, and geriatric nutritional syndromes like protein-energy malnutrition and failure to thrive, in addition to enhancing aging anorexia and cachexia. Therefore, interventions must be developed to include their screening and diagnosis to make early and appropriate treatment to prevent its complications before they become irreversible.

  7. Vitamin B12 deficit and development of geriatric syndromes

    PubMed Central

    2013-01-01

    Vitamin B12 deficiency or cyanocobalamin is a common condition in the elderly. It is repeatedly overlooked due to multiple clinical manifestations that can affect the blood, neurological, gastrointestinal, and cardiovascular systems, skin and mucous membranes. The various presentations of vitamin B12 deficiency are related to the development of geriatric syndromes like frailty, falls, cognitive impairment, and geriatric nutritional syndromes like protein-energy malnutrition and failure to thrive, in addition to enhancing aging anorexia and cachexia. Therefore, interventions must be developed to include their screening and diagnosis to make early and appropriate treatment to prevent its complications before they become irreversible. PMID:24892321

  8. Involuntary movements misdiagnosed as seizure during vitamin B12 treatment.

    PubMed

    Carman, Kursat Bora; Belgemen, Tugba; Yis, Uluc

    2013-11-01

    Seizures and epilepsy are a common problem in childhood. Nonepileptic paroxysmal events are conditions that can mimic seizure and frequent in early childhood. Nonepileptic paroxysmal events can be due to physiological or exaggerated physiological responses, parasomnias, movement disorders, behavioral or psychiatric disturbances, or to hemodynamic, respiratory, or gastrointestinal dysfunction. Vitamin B12 deficiency is a treatable cause of failure to thrive and developmental regression, involuntary movements, and anemia. Involuntary movements rarely may appear a few days after the initiation of vitamin B12 treatments and might be misdiagnosed as seizure. Here, we report 2 patients who presented with involuntary movements with his video image.

  9. Application of 3D-QSAR techniques in anti-HIV-1 drug design--an overview.

    PubMed

    Debnath, Asim Kumar

    2005-01-01

    Despite the availability of several classes of drugs against acquired immunodeficiency syndrome (AIDS) caused by human immunodeficiency virus type 1(HIV-1), this deadly disease showing very little sign of containment, especially in Sub-Saharan Africa and South-East Asia. More than 20 million people died since the first diagnosis of AIDS more than twenty years ago and almost 40 million people are currently living with HIV/AIDS. Structure-based drug design effort was immensely successful in identifying several drugs that are currently available for the treatment of HIV-1. Many applications have been reported on the use of quantitative structure-activity relationship (QSAR) studies to understand the drug-receptor interactions and help in the design of more effective analogs. Extensive application was also reported on the application of 3D-QSAR techniques, such as, Comparative Molecular Field Analysis (CoMFA), Comparative Molecular Similarity Analysis (CoMSIA), pharmacophore generation using Catalyst/HypoGen, free-energy binding analysis, GRID/GOLPE, HINT-based techniques, etc. in anti-HIV-1 drug discovery programs in academia and industry. We have attempted to put together a comprehensive overview on the 3D-QSAR applications in anti-HIV-1 drug design reported in the literature during the last decade.

  10. Discovery of a Potent HIV Integrase Inhibitor That Leads to a Prodrug with Significant anti-HIV Activity

    PubMed Central

    2011-01-01

    Worldwide research efforts in drug discovery involving HIV integrase have produced only one compound, raltegravir, that has been approved for clinical use in HIV/AIDS. As resistance, toxicity, and drug–drug interactions are recurring issues with all classes of anti-HIV drugs, the discovery of novel integrase inhibitors remains a significant scientific challenge. We have designed a lead HIV-1 strand transfer (ST) inhibitor (IC50 70 nM), strategically assembled on a pyridinone scaffold. A focused structure–activity investigation of this parent compound led to a significantly more potent ST inhibitor, 2 (IC50 6 ± 3 nM). Compound 2 exhibits good stability in pooled human liver microsomes. It also displays a notably favorable profile with respect to key human cytochrome P450 (CYP) isozymes and human UDP glucuronosyl transferases (UGTs). The prodrug of inhibitor 2, i.e., compound 10, was found to possess remarkable anti-HIV-1 activity in cell culture (EC50 9 ± 4 nM, CC50 135 ± 7 μM, therapeutic index = 15 000). PMID:22328963

  11. Determining chemical reactivity driving biological activity from SMILES transformations: the bonding mechanism of anti-HIV pyrimidines.

    PubMed

    Putz, Mihai V; Dudaş, Nicoleta A

    2013-07-30

    Assessing the molecular mechanism of a chemical-biological interaction and bonding stands as the ultimate goal of any modern quantitative structure-activity relationship (QSAR) study. To this end the present work employs the main chemical reactivity structural descriptors (electronegativity, chemical hardness, chemical power, electrophilicity) to unfold the variational QSAR though their min-max correspondence principles as applied to the Simplified Molecular Input Line Entry System (SMILES) transformation of selected uracil derivatives with anti-HIV potential with the aim of establishing the main stages whereby the given compounds may inhibit HIV infection. The bonding can be completely described by explicitly considering by means of basic indices and chemical reactivity principles two forms of SMILES structures of the pyrimidines, the Longest SMILES Molecular Chain (LoSMoC) and the Branching SMILES (BraS), respectively, as the effective forms involved in the anti-HIV activity mechanism and according to the present work, also necessary intermediates in molecular pathways targeting/docking biological sites of interest.

  12. Synthesis, anti-HIV activity, integrase enzyme inhibition and molecular modeling of catechol, hydroquinone and quinol labdane analogs.

    PubMed

    Pawar, Rohan; Das, Tiyasa; Mishra, Sanjay; Nutan; Pancholi, Boskey; Gupta, Satish K; Bhat, Sujata V

    2014-01-01

    Labdane analogs with o-quinol, catechol and hydroquinone moiety have been synthesized using Diels-Alder reaction of methyl 3,4-dioxocyclohexa-1,5-diene-carboxylate, 3,4-dioxocyclohexa-1,5-diene-carboxylic acid and 3,6-dioxocyclohexa-1,4-dienecarboxylic acid with mono terpene 1,3-dienes, namely ocimene and myrcene. The resulting molecules and their derivatives were evaluated for their anti-HIV-1 activity using TZM-bl cell based virus infectivity assay. Two molecules 13 and 18 showed anti-HIV activity with IC50 values 5.0 (TI=11) and 4.6 (TI=46)μM, respectively. The compounds 17, 18 and 20 showed efficacy against HIV-1 integrase activity and showed inhibition with IC50 13.4, 11.1 and 11.5μM, respectively. The HIV-1 integrase inhibition activity of these synthetic molecules was comparable with integric acid, the natural fungal metabolite. Molecular modeling studies for the HIV-1 integrase inhibition of these active synthetic molecules indicated the binding to the active site residues of the enzyme.

  13. In vitro anti-HIV-1 activities of kaempferol and kaempferol-7-O-glucoside isolated from Securigera securidaca.

    PubMed

    Behbahani, M; Sayedipour, S; Pourazar, A; Shanehsazzadeh, M

    2014-01-01

    Previously, we reported that the kaempferol and kaempferol-7-O-glucoside isolated from Securigera securidaca showed potent anti-HSV activity. In the present study the anti-HIV-1 activities of kaempferol and kaempferol-7-O-glucoside are investigated at different concentrations (100, 50, 25 and 10 μg/ml) using HIV-1 p24 Antigen kit. Real-time Polymerase chain reaction (RT-PCR) assay was also used for quantification of full range of virus load observed in treated and untreated cells. According to the results of RT- PCR, tested compounds at a concentration of 100 μg/ml exerted potent inhibitory effect. Time of drug addition experiments demonstrated that these compounds exerted their inhibitory effects on the early stage of HIV infection. The results also showed potent anti-HIV-1 reverse transcriptase activity. Antiviral activity of kaempferol-7-O-glucoside was more pronounced than that of kaempferol. These findings demonstrate that kaempferol-7-O-glucoside could be considered as a new potential drug candidate for the treatment of HIV infection which requires further assessments.

  14. The photochemical mechanism of a B12-dependent photoreceptor protein

    PubMed Central

    Kutta, Roger J.; Hardman, Samantha J. O.; Johannissen, Linus O.; Bellina, Bruno; Messiha, Hanan L.; Ortiz-Guerrero, Juan Manuel; Elías-Arnanz, Montserrat; Padmanabhan, S.; Barran, Perdita; Scrutton, Nigel S.; Jones, Alex R.

    2015-01-01

    The coenzyme B12-dependent photoreceptor protein, CarH, is a bacterial transcriptional regulator that controls the biosynthesis of carotenoids in response to light. On binding of coenzyme B12 the monomeric apoprotein forms tetramers in the dark, which bind operator DNA thus blocking transcription. Under illumination the CarH tetramer dissociates, weakening its affinity for DNA and allowing transcription. The mechanism by which this occurs is unknown. Here we describe the photochemistry in CarH that ultimately triggers tetramer dissociation; it proceeds via a cob(III)alamin intermediate, which then forms a stable adduct with the protein. This pathway is without precedent and our data suggest it is independent of the radical chemistry common to both coenzyme B12 enzymology and its known photochemistry. It provides a mechanistic foundation for the emerging field of B12 photobiology and will serve to inform the development of a new class of optogenetic tool for the control of gene expression. PMID:26264192

  15. Considering the case for vitamin B12 fortification of flour

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reasons to fortify flour with vitamin B12 are considered, which include the high prevalence of depletion and deficiency of this vitamin that occurs in persons of all ages in resource-poor countries and in elderly in wealthier countries, as well as the adverse functional consequences of poor vitamin ...

  16. Cyanide-bridged vitamin B12-cisplatin conjugates.

    PubMed

    Mundwiler, Stefan; Spingler, Bernhard; Kurz, Philipp; Kunze, Susanne; Alberto, Roger

    2005-07-04

    cis-[PtCl(OH2)(NH3)2]+, the monoactivated form of cisplatin, reacts with the cyano ligand of cobalt in vitamin B12 (cyanocobalamin) to form a Co-C[triple chemical bond]N-Pt conjugate (1). Compound 1 is prepared in good yield directly in aqueous solution. The remaining chloride ligand of Pt(II) is labile. It hydrolyzes slowly in aqueous solution and can be exchanged by stronger coordinating ligands, such as 9-methylguanine or 2'-deoxyguanosine, to yield vitamin B12-nucleobase conjugates. X-ray structures of the vitamin B12-cisplatin conjugate 1 as well as of the product with coordinated 9-methylguanine (2) are presented. The coordination geometry at Pt(II) is almost perfectly square-planar. The structure of the cobalamin compound remains essentially unchanged when compared with the original B(12) structure. The guanine moiety of compound 2 binds in a 45 degrees angle to the cisplatin molecule and interacts with neighboring molecules by means of pi stacking and hydrogen bonds.

  17. Anaerobic biosynthesis of the lower ligand of vitamin B12

    PubMed Central

    Hazra, Amrita B.; Han, Andrew W.; Mehta, Angad P.; Mok, Kenny C.; Osadchiy, Vadim; Begley, Tadhg P.; Taga, Michiko E.

    2015-01-01

    Vitamin B12 (cobalamin) is required by humans and other organisms for diverse metabolic processes, although only a subset of prokaryotes is capable of synthesizing B12 and other cobamide cofactors. The complete aerobic and anaerobic pathways for the de novo biosynthesis of B12 are known, with the exception of the steps leading to the anaerobic biosynthesis of the lower ligand, 5,6-dimethylbenzimidazole (DMB). Here, we report the identification and characterization of the complete pathway for anaerobic DMB biosynthesis. This pathway, identified in the obligate anaerobic bacterium Eubacterium limosum, is composed of five previously uncharacterized genes, bzaABCDE, that together direct DMB production when expressed in anaerobically cultured Escherichia coli. Expression of different combinations of the bza genes revealed that 5-hydroxybenzimidazole, 5-methoxybenzimidazole, and 5-methoxy-6-methylbenzimidazole, all of which are lower ligands of cobamides produced by other organisms, are intermediates in the pathway. The bza gene content of several bacterial and archaeal genomes is consistent with experimentally determined structures of the benzimidazoles produced by these organisms, indicating that these genes can be used to predict cobamide structure. The identification of the bza genes thus represents the last remaining unknown component of the biosynthetic pathway for not only B12 itself, but also for three other cobamide lower ligands whose biosynthesis was previously unknown. Given the importance of cobamides in environmental, industrial, and human-associated microbial metabolism, the ability to predict cobamide structure may lead to an improved ability to understand and manipulate microbial metabolism. PMID:26246619

  18. Vitamin-B12 deficiency following therapy in gynecologic oncology

    SciTech Connect

    Bandy, L.C.; Clarke-Pearson, D.L.; Creasman, W.T.

    1984-03-01

    Vitamin-B12 deficiency results from inadequate absorption of the vitamin by the distal ileum and depletion of available stores. Both radiotherapy and intestinal resection can contribute to development of this condition. The significance of this problem in gynecologic oncology is discussed and two patients are described.

  19. A Cross Section Study to Determine the Prevalence of Antibodies against HIV Infection among Hepatitis B and C Infected Individuals

    PubMed Central

    Flores, Geane L.; de Almeida, Adilson J.; Miguel, Juliana C.; Cruz, Helena M.; Portilho, Moyra M.; de P. Scalioni, Letícia; Marques, Vanessa A.; Lewis-Ximenez, Lia Laura; Lampe, Elisabeth; Melo Villar, Livia

    2016-01-01

    (1) Background: There are limited data regarding human immunodeficiency virus (HIV) prevalence among hepatitis B virus (HBV) or hepatitis C virus (HCV) infected individuals. The aim of this cross-sectional study is to determine the prevalence of HBV and HCV infection among HIV individuals; (2) Methods: A total of 409 patients (126 HBV+ and 283 HCV+) referred to the Brazilian Reference Laboratory for Viral Hepatitis from 2010 to 2013 donated serum samples. Anti-HIV, HBsAg, anti-HBc, anti-HBs, anti-HBcIgM, anti-HBe, HBeAg, and anti-HCV antibodies were measured, and anti-HCV positive samples were tested for viral RNA and genotype; (3) Results: The anti-HIV antibody prevalence was 10.31% and 4.59% among HBV+ and HCV+ patients, respectively. The HCV mean (SD) viral load was log 5.14 ± 1.64 IU/mL, and genotype I was most prevalent (163/283). Anti-HBs and anti-HBc were detected in 40% and 26% of HCV+ individuals, respectively. Among the HBV+ population, the presence of anti-HIV antibodies was associated with male gender, marital status (married), tattoo, sexual orientation, sexual practices (oral sex and anal sex), history of sexually transmitted diseases (STDs), history of viral hepatitis treatment, and a sexual partner with hepatitis or HIV. For the HCV+ group, the presence of anti-HIV antibodies was associated with female gender, marital status (married), anal intercourse, previous history of STDs, and number of sexual partners; (4) Conclusion: A high prevalence of anti-HIV antibodies was found among individuals with HBV and HCV, showing the importance of education programmes towards HIV infection among HBV- and HCV-infected individuals. PMID:26978383

  20. Folate–vitamin B-12 interaction in relation to cognitive impairment, anemia, and biochemical indicators of vitamin B-12 deficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous reports on pernicious anemia treatment suggested that high folic acid intake adversely influences the natural history of vitamin B-12 deficiency, which affects many elderly individuals. However, experimental investigation of this hypothesis is unethical, and the few existing observational d...

  1. TOXOPLASMA AND VIRAL ANTIBODIES AMONG HIV PATIENTS AND INMATES IN CENTRAL JAVA, INDONESIA.

    PubMed

    Sari, Yulia; Haryati, Sri; Raharjo, Irvan; Prasetyo, Afiono Agung

    2015-11-01

    In Indonesia, Toxoplasma and its associations with blood-borne viruses have been poorly studied. In order to study the association between anti-Toxoplasma antibodies and blood-borne viral antibodies, blood samples from 497 participants (375 inmates from four prisons in Central Java, Indonesia and 122 HIV patients at a Voluntary Counseling and Testing Clinic in Surakarta, Indonesia) were tested for serological markers of Toxoplasma, human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and human T-lymphotropic virus types I and II (HTLV-1/2). Anti-Toxoplasma IgG and IgM positivity rates were 41.6% and 3.6%, respectively. One point two percent of participants was positive for both anti-Toxoplasma IgG and IgM antibodies. Sixteen point five percent, 11.3%, 2.6% and 2.8% of participants were positive for anti- Toxoplasma IgG combined with anti-HCV antibodies, anti-Toxoplasma IgG combined with anti-HIV antibodies, anti-Toxoplasma IgM combined with anti-HIV antibodes and anti-Toxoplasma IgG combined with both anti-HIV and anti-HCV antibodies, respectively. Anti-Toxoplasma IgM seropositivity was associated with anti-HIV (aOR = 4.3; 95% CI: 1.112-16.204, p = 0.034). Anti-Toxoplasma IgG antibodies were associated with anti-HCV (aOR = 2.8; 95% CI: 1.749-4.538, p < 0.001) and history of injection drug use (aOR = 3.1; 95% CI: 1.905-5.093, p < 0.001). In conclusion, we recommend patients with HIV, HCV infection and injection drug users should be screened for Toxoplasma infection in Indonesia.

  2. Oxidative Stress Markers in Vitamin B12 Deficiency.

    PubMed

    Misra, Usha Kant; Kalita, Jayantee; Singh, Sandeep Kumar; Rahi, Sushil Kumar

    2017-03-01

    In this study, we report the status of oxidative stress markers in vitamin B12 deficiency and their relation to clinical, laboratory, and neurophysiological findings. Fifty-one subjects with serum vitamin B12 deficiency (<211 pg/ml) were included. Plasma glutathione (GSH), malondialdehyde (MDA) and serum total antioxidant capacity (TAC) were measured in the patients and 53 controls. These markers were also compared between subacute combined degeneration (SACD) and non-SACD vitamin B12 deficiency patients groups as well as with normal controls. In the patients, GSH, MDA and TAC were correlated with demographic, clinical, hematological, biochemical, nerve conduction study (NCS), visual evoked potential (VEP) and somatosensory-evoked potential (SEP) findings. In the study group, 20 (39.2 %) patients had SACD manifesting with myeloneuropathy, cognitive or behavioral abnormalities, and 31(60.8 %) patients had non-SACD neurological manifestations. The GSH (2.46 ± 0.32 vs. 2.70 ± 0.36 mg/dl; P = 0.002) and TAC (2.13 ± 0.38 vs. 2.33 ± 0.24 nmol Trolox eq/l, P = 0.005) levels were lower, and MDA levels (4.01 ± 0.69 vs. 3.00 ± 0.45 nmol/ml, P < 0.001) were higher in B12 deficiency group compared with controls. Similar trend was found in SACD and non-SACD vitamin B12 deficiency groups. GSH levels correlated with abnormal VEP (r = 0.54; P < 0.01), TAC with female gender (r = 0.43; P = 0.002) and joint position impairment (r = -0.34; P = 0.01), and MDA with LDH (r = 0.41; P = 0.01). Vitamin B12 deficiency was associated with reduction in GSH and TAC and increase in MDA levels which were more marked in SACD compared to non-SACD group.

  3. Vector-Mediated In Vivo Antibody Expression.

    PubMed

    Schnepp, Bruce C; Johnson, Philip R

    2014-08-01

    This article focuses on a novel vaccine strategy known as vector-mediated antibody gene transfer, with a particular focus on human immunodeficiency virus (HIV). This strategy provides a solution to the problem of current vaccines that fail to generate neutralizing antibodies to prevent HIV-1 infection and AIDS. Antibody gene transfer allows for predetermination of antibody affinity and specificity prior to "immunization" and avoids the need for an active humoral immune response against the HIV envelope protein. This approach uses recombinant adeno-associated viral (rAAV) vectors, which have been shown to transduce muscle with high efficiency and direct the long-term expression of a variety of transgenes, to deliver the gene encoding a broadly neutralizing antibody into the muscle. Following rAAV vector gene delivery, the broadly neutralizing antibodies are endogenously synthesized in myofibers and passively distributed to the circulatory system. This is an improvement over classical passive immunization strategies that administer antibody proteins to the host to provide protection from infection. Vector-mediated gene transfer studies in mice and monkeys with anti-HIV and simian immunodeficiency virus (SIV)-neutralizing antibodies demonstrated long-lasting neutralizing activity in serum with complete protection against intravenous challenge with virulent HIV and SIV. These results indicate that existing potent anti-HIV antibodies can be rapidly moved into the clinic. However, this methodology need not be confined to HIV. The general strategy of vector-mediated antibody gene transfer can be applied to other difficult vaccine targets such as hepatitis C virus, malaria, respiratory syncytial virus, and tuberculosis.

  4. The high-pressure compressibility of B12P2

    NASA Astrophysics Data System (ADS)

    Gao, Yang; Zhou, Mi; Wang, Haiyan; Ji, Cheng; Whiteley, C. E.; Edgar, J. H.; Liu, Haozhe; Ma, Yanzhang

    2017-03-01

    In situ high pressure synchrotron X-ray diffraction measurements were performed on icosahedral boron phosphide (B12P2) to 43.2 GPa. No structural phase transition occurs over this pressure range. The bulk modulus of B12P2 is KOT = 207 ± 7 GPa with pressure derivative of K'OT = 6.6 ± 0.8 . The structure is most compressible along the chain formed by phosphorus and boron atoms in the crystal structure. It is believed that the compressibility of boron-rich compounds at close to ambient pressure is determined by the boron icosahedral structure, while the inclusive atoms (both boron and non-boron) between the icosahedra determine the high-pressure compressibility and structure stability.

  5. Vitamin B12 deficiency presenting as acute ataxia.

    PubMed

    Crawford, John Ross; Say, Daphne

    2013-03-26

    A previously healthy 7-year-old Caucasian boy was hospitalised for evaluation of acute ataxia and failure to thrive, initially suspicious for an intracranial mass. Weight and body mass index were below the third percentile and he demonstrated loss of joint position and vibratory sense on examination. Laboratory studies revealed megaloblastic anaemia while an initial MRI of the brain showed no evidence of mass lesions or other abnormalities. A dietary history revealed the child subscribed to a restrictive vegan diet with little to no intake of animal products or other fortified foods. The child was diagnosed with presumed vitamin B12 deficiency and was treated with intramuscular B12 injections. Neurological symptoms resolved promptly within several days after starting therapy. This case underlines the importance of assessing nutritional status in the evaluation of neurological dysfunction in the pediatric patient.

  6. Oral cobalamin (vitamin B(12)) treatment. An update.

    PubMed

    Andrès, E; Dali-Youcef, N; Vogel, T; Serraj, K; Zimmer, J

    2009-02-01

    The objective of this review was to evaluate oral cobalamin (vitamin B(12)) therapy in adult and elderly patients, from the perspective of a hematologist. PubMed was systematically searched for English and French articles published from January 1990 to January 2007. Data from our working group, the 'Groupe d'étude des carences en vitamine B(12)des Hôpitaux Universitaires de Strasbourg', have also been included. Several prospective studies in well-determined population (n = 4), prospective randomized studies (n = 3) and a systematic review by the Cochrane group (n = 1) provide evidence that oral cobalamin therapy may adequately treat cobalamin deficiency, particularly hematological abnormalities or manifestations. These studies suggest that at least 1000 microg/day of oral cyanocobalmin are needed for pernicious anemia and a mean daily dose of 250 microg for food-cobalamin malabsorption. This present review confirms the previously reported efficacy of oral cobalamin treatment in adult and elderly patients.

  7. Dietary Sources of Vitamin B-12 and Their Association with Vitamin B-12 Status Markers in Healthy Older Adults in the B-PROOF Study.

    PubMed

    Brouwer-Brolsma, Elske M; Dhonukshe-Rutten, Rosalie A M; van Wijngaarden, Janneke P; Zwaluw, Nikita L van der; Velde, Nathalie van der; de Groot, Lisette C P G M

    2015-09-14

    Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between dietary sources of vitamin B-12 (meat, fish and shellfish, eggs, dairy) and serum vitamin B-12, using cross-sectional data of 600 Dutch community-dwelling adults (≥65 years). Dietary intake was assessed with a validated food frequency questionnaire. Vitamin B-12 concentrations were measured in serum. Associations were studied over tertiles of vitamin B-12 intake using P for trend, by calculating prevalence ratios (PRs), and splines. Whereas men had significantly higher vitamin B-12 intakes than women (median (25th-75th percentile): 4.18 (3.29-5.38) versus 3.47 (2.64-4.40) μg/day), serum vitamin B-12 did not differ between the two sexes (mean ± standard deviation (SD): 275 ± 104 pmol/L versus 290 ± 113 pmol/L). Higher intakes of dairy, meat, and fish and shellfish were significantly associated with higher serum vitamin B-12 concentrations, where meat and dairy-predominantly milk were the most potent sources. Egg intake did not significantly contribute to higher serum vitamin B-12 concentrations. Thus, dairy and meat were the most important contributors to serum vitamin B-12, followed by fish and shellfish.

  8. Dietary Sources of Vitamin B-12 and Their Association with Vitamin B-12 Status Markers in Healthy Older Adults in the B-PROOF Study

    PubMed Central

    Brouwer-Brolsma, Elske M.; Dhonukshe-Rutten, Rosalie A. M.; van Wijngaarden, Janneke P.; van der Zwaluw, Nikita L.; van der Velde, Nathalie; de Groot, Lisette C. P. G. M.

    2015-01-01

    Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between dietary sources of vitamin B-12 (meat, fish and shellfish, eggs, dairy) and serum vitamin B-12, using cross-sectional data of 600 Dutch community-dwelling adults (≥65 years). Dietary intake was assessed with a validated food frequency questionnaire. Vitamin B-12 concentrations were measured in serum. Associations were studied over tertiles of vitamin B-12 intake using P for trend, by calculating prevalence ratios (PRs), and splines. Whereas men had significantly higher vitamin B-12 intakes than women (median (25th–75th percentile): 4.18 (3.29–5.38) versus 3.47 (2.64–4.40) μg/day), serum vitamin B-12 did not differ between the two sexes (mean ± standard deviation (SD): 275 ± 104 pmol/L versus 290 ± 113 pmol/L). Higher intakes of dairy, meat, and fish and shellfish were significantly associated with higher serum vitamin B-12 concentrations, where meat and dairy—predominantly milk were the most potent sources. Egg intake did not significantly contribute to higher serum vitamin B-12 concentrations. Thus, dairy and meat were the most important contributors to serum vitamin B-12, followed by fish and shellfish. PMID:26389945

  9. Disorders of vitamin B12 metabolism presenting through newborn screening.

    PubMed

    Fletcher, Janice

    2008-12-01

    Elevated propionyl C3 carnitine is the most common abnormality seen in tandem mass spectrometry newborn screening profiles, with an incidence of 0.15% seen in our South Australian newborn screening programme. The most common cause for this result in our population is vitamin B12 deficiency but differential diagnoses include the inherited disorders of propionic and methylmalonic acid metabolism and cobalamin deficiencies. An approach to confirmatory testing and subsequent management of infants with elevated propionic carnitine is presented.

  10. Atomic Mass and Nuclear Binding Energy for B-12 (Boron)

    NASA Astrophysics Data System (ADS)

    Sukhoruchkin, S. I.; Soroko, Z. N.

    This document is part of the Supplement containing the complete sets of data of Subvolume A `Nuclei with Z = 1 - 54' of Volume 22 `Nuclear Binding Energies and Atomic Masses' of Landolt-Börnstein - Group I `Elementary Particles, Nuclei and Atoms'. It provides atomic mass, mass excess, nuclear binding energy, nucleon separation energies, Q-values, and nucleon residual interaction parameters for atomic nuclei of the isotope B-12 (Boron, atomic number Z = 5, mass number A = 12).

  11. A vitamin B-12 supplement of 500 μg/d for eight weeks does not normalize urinary methylmalonic acid or other biomarkers of vitamin B-12 status in elderly people with moderately poor vitamin B-12 status.

    PubMed

    Hill, Marilyn H; Flatley, Janet E; Barker, Margo E; Garner, Clare M; Manning, Nigel J; Olpin, Simon E; Moat, Stuart J; Russell, Jean; Powers, Hilary J

    2013-02-01

    Plasma vitamin B-12 is the most commonly used biomarker of vitamin B-12 status, but the predictive value for low vitamin B-12 status is poor. The urinary methylmalonic acid (uMMA) concentration has potential as a functional biomarker of vitamin B-12 status, but the response to supplemental vitamin B-12 is uncertain. A study was conducted to investigate the responsiveness of uMMA to supplemental vitamin B-12 in comparison with other biomarkers of vitamin B-12 status [plasma vitamin B-12, serum holotranscobalamin (holoTC), plasma MMA] in elderly people with moderately poor vitamin B-12 status. A double-blind, placebo-controlled, randomized 8-wk intervention study was carried out using vitamin B-12 supplements (500 μg/d, 100 μg/d, and 10 μg/d cyanocobalamin) in 100 elderly people with a combined plasma vitamin B-12 <250 pmol/L and uMMA ratio (μmol MMA/mmol creatinine) >1.5. All biomarkers had a dose response to supplemental vitamin B-12. Improvements in plasma vitamin B-12 and serum holoTC were achieved at cobalamin supplements of 10 μg/d, but even 500 μg/d for 8 wk did not normalize plasma vitamin B-12 in 8% and serum holoTC in 12% of people. The response in uMMA was comparable with plasma MMA; 15-25% of people still showed evidence of metabolic deficiency after 500 μg/d cobalamin for 8 wk. There was a differential response in urinary and plasma MMA according to smoking behavior; the response was enhanced in ex-smokers compared with never-smokers. uMMA offers an alternative marker of metabolic vitamin-B12 status, obviating the need for blood sampling.

  12. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation.

    PubMed

    Rizzo, Gianluca; Laganà, Antonio Simone; Rapisarda, Agnese Maria Chiara; La Ferrera, Gioacchina Maria Grazia; Buscema, Massimo; Rossetti, Paola; Nigro, Angela; Muscia, Vincenzo; Valenti, Gaetano; Sapia, Fabrizio; Sarpietro, Giuseppe; Zigarelli, Micol; Vitale, Salvatore Giovanni

    2016-11-29

    Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.

  13. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

    PubMed Central

    Rizzo, Gianluca; Laganà, Antonio Simone; Rapisarda, Agnese Maria Chiara; La Ferrera, Gioacchina Maria Grazia; Buscema, Massimo; Rossetti, Paola; Nigro, Angela; Muscia, Vincenzo; Valenti, Gaetano; Sapia, Fabrizio; Sarpietro, Giuseppe; Zigarelli, Micol; Vitale, Salvatore Giovanni

    2016-01-01

    Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism. PMID:27916823

  14. Aspernigrins with anti-HIV-1 activities from the marine-derived fungus Aspergillus niger SCSIO Jcsw6F30.

    PubMed

    Zhou, Xuefeng; Fang, Wei; Tan, Suiyi; Lin, Xiuping; Xun, Tianrong; Yang, Bingjie; Liu, Shuwen; Liu, Yonghong

    2016-01-15

    Two new 2-benzylpyridin-4-one containing metabolites, aspernigrins C (3) and D (4), together with six known compounds (1, 2, and 5-8), were isolated from the marine-derived fungus Aspergillus niger SCSIO Jcsw6F30. The structures of the new compounds were determined by NMR, MS, and optical rotation analyses. All the isolated compounds were evaluated for their inhibitory activities against infection with HIV-1 SF162 in TZM-bl cells. Malformin C (5) showed the strongest anti-HIV-1 activity with IC50 of 1.4±0.06μM (selectivity index, 11.4), meanwhile aspernigrin C (3) also exhibited potent activity with IC50 of 4.7±0.4μM (selectivity index, 7.5).

  15. Forms and Amounts of Vitamin B12 in Infant Formula: A Pilot Study

    PubMed Central

    Greibe, Eva; Nexo, Ebba

    2016-01-01

    Purpose Infant formula is based on cow’s milk and designed to mimic breast milk for substitution. Vitamin B12 (B12) is bound to proteins in both breast milk and cow’s milk, and in milk from both species the vitamin occurs mainly in its natural form such as hydroxo-B12 with little or no synthetic B12 (cyano-B12). Here we test commercially available infant formulas. Methods Eleven commercially available infant formulas were measured for content of B12 and analyzed for the presence of B12-binding proteins and forms of B12 using size exclusion chromatography and HPLC. Results All infant formulas contained B12 by and large in accord with the informations given on the package inserts. None of the formulas contained protein-bound B12, and cyano-B12 accounted for 19–78% of the total amount of B12 present, while hydroxo-B12 constituted more or less the rest. Conclusions This pilot study shows that infant formula differs from breast milk in providing the infant with free B12, rather than protein-bound B12, and by a relative high content of cyano-B12. The consequence of supplying the infant with synthetic cyano-B12 remains to be elucidated. PMID:27851744

  16. Methamphetamine inhibits HIV-1 replication in CD4+ T cells by modulating anti-HIV-1 miRNA expression.

    PubMed

    Mantri, Chinmay K; Mantri, Jyoti V; Pandhare, Jui; Dash, Chandravanu

    2014-01-01

    Methamphetamine is the second most frequently used illicit drug in the United States. Methamphetamine abuse is associated with increased risk of HIV-1 acquisition, higher viral loads, and enhanced HIV-1 pathogenesis. Although a direct link between methamphetamine abuse and HIV-1 pathogenesis remains to be established in patients, methamphetamine has been shown to increase HIV-1 replication in macrophages, dendritic cells, and cells of HIV transgenic mice. Intriguingly, the effects of methamphetamine on HIV-1 replication in human CD4(+) T cells that serve as the primary targets of infection in vivo are not clearly understood. Therefore, we examined HIV-1 replication in primary CD4(+) T cells in the presence of methamphetamine in a dose-dependent manner. Our results demonstrate that methamphetamine had a minimal effect on HIV-1 replication at concentrations of 1 to 50 μmol/L. However, at concentrations >100 μmol/L, it inhibited HIV-1 replication in a dose-dependent manner. We also discovered that methamphetamine up-regulated the cellular anti-HIV-1 microRNAs (miR-125b, miR-150, and miR-28-5p) in CD4(+) T cells. Knockdown experiments illustrated that up-regulation of the anti-HIV miRNAs inhibited HIV-1 replication. These results are contrary to the paradigm that methamphetamine accentuates HIV-1 pathogenesis by increasing HIV-1 replication. Therefore, our findings underline the complex interaction between drug use and HIV-1 and necessitate comprehensive understanding of the effects of methamphetamine on HIV-1 pathogenesis.

  17. Phenotypic characterization of CD8+ T cell populations in HIV disease and in anti-HIV immunity.

    PubMed

    Watret, K C; Whitelaw, J A; Froebel, K S; Bird, A G

    1993-04-01

    The CD8+ T cell population is believed to play an important role in the control of viral infection, both for suppression of viral replication and for cytotoxic activity against viral infected cells. Elevated numbers of CD8+ T cells have been demonstrated in HIV infection, and CD8+ cytotoxic T cell (CTL) activity is associated with the early, asymptomatic stage of disease. We investigated the phenotypic characteristics of the CD8 population, in whole blood, in HIV disease and determined the predominant CD8+ subpopulation involved in anti-HIV CTL activity. We found that CD8+ T cells co-expressing markers of activation (HLA-DR), memory (CD45RO, CD29), and cytotoxic activity (S6F1) were significantly elevated in the early stages of disease, while the numbers of naive (CD45RA) cells remained unchanged. Progression to AIDS resulted in an overall loss of absolute CD8+ T cells, though the percentages of CD8+ HLA-DR+ and CD8+ S6F1+ remained elevated. In contrast to patients in the late stages of disease, anti-HIVgag CTL activity, following in vitro stimulation, was present in most HIV+ asymptomatic subjects and was associated with an expansion of CD8+ HLA-DR+ and CD8+ CD45RO+ cells. The absence of CTL activity was associated with a reduced ability of these populations to expand in vitro and with a significant loss of peripheral CD4+ T cells, independent of clinical stage. We suggest that CD8+ expressing HLA-DR+ CD45RO+ and S6F1+ play an important role in anti-HIV cytotoxicity.

  18. CCL20/MIP3a is a Novel Anti-HIV-1 Molecule of the Human Female Reproductive Tract

    PubMed Central

    Ghosh, Mimi; Shen, Zheng; Schaefer, Todd M.; Fahey, John V.; Gupta, Phalguni; Wira, Charles R.

    2013-01-01

    Problem CCL20/MIP3α is a chemokine for immature dendritic cells as well as an antibacterial against gram-positive and gram-negative bacteria. The role of CCL20/MIP3α as an antiviral is unknown. In this study, we have examined the production of CCL20/MIP3α by epithelial cells from the upper female reproductive tract as well as its activity as an antiviral molecule. Method of study Primary uterine and Fallopian tube epithelial cells were treated with Poly(I:C) and CCL20/MIP3α mRNA and protein was measured by Real-time RT-PCR and ELISA assays. Anti-HIV activity was determined using an indicator cell line TZM-bl and quantified by using a luminometer. Results Primary uterine and Fallopian tube epithelial cells produce CCL20/MIP3α constitutively and the production is enhanced following stimulation with viral double-stranded RNA mimic Poly(I:C). Recombinant CCL20/MIP3α was able to inhibit both T-cell-tropic X4/IIIB and macrophage-tropic R5/BaL HIV-1 when virus was directly incubated with CCL20/MIP3α but not when CCL20/MIP3α was added to cells either prior to infection or post-infection. This suggests that the mechanism of inhibition is likely to be a direct interaction between HIV-1 and CCL20/MIP3α. Conclusion This study demonstrates that CCL20/MIP3α is an important endogenous anti-HIV-1 microbicide of the female reproductive tract. PMID:19527233

  19. High-dose compared with low-dose vitamin B-12 supplement use is not associated with higher vitamin B-12 status in children, adolescents, and older adults.

    PubMed

    MacFarlane, Amanda J; Shi, Yipu; Greene-Finestone, Linda S

    2014-06-01

    Over-the-counter vitamin supplements on the Canadian market are permitted to contain a daily vitamin B-12 dose of up to 1000 μg. Our objective was to determine the association between total daily vitamin B-12 supplement dose and markers of vitamin B-12 status in Canadians. Blood collected from a nationally representative sample aged 6-79 y (n = ∼5600) in the Canadian Health Measures Survey (2007-2009) was analyzed for serum vitamin B-12 and plasma total homocysteine (tHcy). Total daily intake of vitamin B-12 from single and multivitamin supplements was calculated. Individuals that indicated proton pump inhibitor or vitamin B-12 injection treatment were excluded from the supplement dose and tHcy analyses; folate-deficient individuals were also excluded from the tHcy analysis. Twenty-three percent of children, 12.3% of adolescents, and 25.5% of adults consumed a vitamin B-12-containing supplement. Supplement users had 33% higher serum vitamin B-12 and 4.2% higher prevalence of adequacy than did non-supplement users. Children and adolescents consuming >10 μg/d supplemental vitamin B-12 did not demonstrate higher serum vitamin B-12, higher prevalence of serum vitamin B-12 adequacy, or lower tHcy than did those consuming >0-10 μg/d. The association between serum vitamin B-12 reached a plateau at doses of >25 and >10-25 μg/d in adults aged 46-59 and 60-79 y, respectively. The prevalences of serum vitamin B-12 adequacy and normal tHcy, and tHcy did not differ by vitamin B-12 supplement dose in adults >45 y. In this cross-sectional study, vitamin B-12 supplement doses >10-25 μg/d were not associated with higher vitamin B-12 status in children, adolescents, or older adults compared with lower doses.

  20. 29 CFR 780.403 - Employee basis of exemption under section 13(b)(12).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Employee basis of exemption under section 13(b)(12). 780... Requirements Under Section 13(b)(12) § 780.403 Employee basis of exemption under section 13(b)(12). Section 13(b)(12) exempts “any employee employed in * * *.” It is clear from this language that it is...

  1. 26 CFR 1.367(b)-12 - Subsequent treatment of amounts attributed or included in income.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... included in income. 1.367(b)-12 Section 1.367(b)-12 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Effects on Corporation § 1.367(b)-12....367(b)-12(b) through (e) of this chapter (as in effect prior to January 11, 2001, see 26 CFR part...

  2. 26 CFR 1.367(b)-12 - Subsequent treatment of amounts attributed or included in income.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... included in income. 1.367(b)-12 Section 1.367(b)-12 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Effects on Corporation § 1.367(b)-12....367(b)-12(b) through (e) of this chapter (as in effect prior to January 11, 2001, see 26 CFR part...

  3. 26 CFR 1.367(b)-12 - Subsequent treatment of amounts attributed or included in income.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... included in income. 1.367(b)-12 Section 1.367(b)-12 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... § 1.367(b)-12 Subsequent treatment of amounts attributed or included in income. (a) In general. This...) Applicable rules. See § 7.367(b)-12(b) through (e) of this chapter (as in effect prior to January 11,...

  4. 26 CFR 1.367(b)-12 - Subsequent treatment of amounts attributed or included in income.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... included in income. 1.367(b)-12 Section 1.367(b)-12 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... § 1.367(b)-12 Subsequent treatment of amounts attributed or included in income. (a) In general. This...) Applicable rules. See § 7.367(b)-12(b) through (e) of this chapter (as in effect prior to January 11,...

  5. 29 CFR 780.403 - Employee basis of exemption under section 13(b)(12).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Employee basis of exemption under section 13(b)(12). 780... Requirements Under Section 13(b)(12) § 780.403 Employee basis of exemption under section 13(b)(12). Section 13(b)(12) exempts “any employee employed in * * *.” It is clear from this language that it is...

  6. 29 CFR 780.403 - Employee basis of exemption under section 13(b)(12).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Employee basis of exemption under section 13(b)(12). 780... Requirements Under Section 13(b)(12) § 780.403 Employee basis of exemption under section 13(b)(12). Section 13(b)(12) exempts “any employee employed in * * *.” It is clear from this language that it is...

  7. 26 CFR 1.367(b)-12 - Subsequent treatment of amounts attributed or included in income.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... included in income. 1.367(b)-12 Section 1.367(b)-12 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... § 1.367(b)-12 Subsequent treatment of amounts attributed or included in income. (a) In general. This...) Applicable rules. See § 7.367(b)-12(b) through (e) of this chapter (as in effect prior to January 11,...

  8. 29 CFR 780.403 - Employee basis of exemption under section 13(b)(12).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Employee basis of exemption under section 13(b)(12). 780... Requirements Under Section 13(b)(12) § 780.403 Employee basis of exemption under section 13(b)(12). Section 13(b)(12) exempts “any employee employed in * * *.” It is clear from this language that it is...

  9. 29 CFR 780.403 - Employee basis of exemption under section 13(b)(12).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Employee basis of exemption under section 13(b)(12). 780... Requirements Under Section 13(b)(12) § 780.403 Employee basis of exemption under section 13(b)(12). Section 13(b)(12) exempts “any employee employed in * * *.” It is clear from this language that it is...

  10. Structural Insights on the Role of Antibodies in HIV-1 Vaccine and Therapy

    PubMed Central

    West, Anthony P.; Scharf, Louise; Scheid, Johannes F.; Klein, Florian; Bjorkman, Pamela J.; Nussenzweig, Michel C.

    2014-01-01

    Despite 30 years of effort, there is no effective vaccine for HIV-1. However, antibodies can prevent HIV-1 infection in humanized mice and macaques when passively transferred. New single-cell-based methods have uncovered many broad and potent donor-derived antibodies, and structural studies have revealed the molecular bases for their activities. The new data suggest why such antibodies are difficult to elicit and inform HIV-1 vaccine development efforts. In addition to protecting against infection, the newly identified antibodies can suppress active infections in mice and macaques, suggesting they could be valuable additions to anti-HIV-1 therapies and to strategies to eradicate HIV-1 infection. PMID:24529371

  11. Antithyroglobulin antibody

    MedlinePlus

    Thyroglobulin antibody; Thyroiditis - thyroglobulin antibody; Hypothyroidism - thyroglobulin antibody; Thyroiditis - thyroglobulin antibody; Graves disease - thyroglobulin antibody; Underactive thyroid - thyroglobulin antibody

  12. Access to organometallic arylcobaltcorrins through radical synthesis: 4-ethylphenylcobalamin, a potential "antivitamin B(12)".

    PubMed

    Ruetz, Markus; Gherasim, Carmen; Gruber, Karl; Fedosov, Sergey; Banerjee, Ruma; Kräutler, Bernhard

    2013-02-25

    Locked B(12): 4-Ethylphenylcobalamin, a novel organometallic arylcobalamin, has been synthesized in a radical reaction. This vitamin B(12) antimetabolite features a strong Co-C bond, and represents a "locked" form of vitamin B(12) . It may be used in animal studies to induce functional vitamin B(12) deficiency artificially to help clarify still controversial issues related to the pathophysiology of vitamin B(12) deficiency.

  13. [Macrocytosis, polyneuropathy and posterior column disorders caused by malabsorption of protein-bound vitamin B12].

    PubMed

    Mazure, A; Bieger, R; Lambregts, P C; Wiarda, K S

    1990-03-31

    This case report concerns a patient with a vitamin B12 deficiency and a normal Schilling test, who had macrocytosis of many years' duration and finally polyneuropathy. All known causes of a vitamin B12 deficiency were excluded. When the Schilling test was performed with egg consumption, excretion of vitamin B12 was clearly diminished. It appears highly likely that this vitamin B12 deficiency developed as a result of malabsorption of protein-bound vitamin B12.

  14. Effect of a Klamath algae product ("AFA-B12") on blood levels of vitamin B12 and homocysteine in vegan subjects: a pilot study.

    PubMed

    Baroni, Luciana; Scoglio, Stefano; Benedetti, Serena; Bonetto, Chiara; Pagliarani, Silvia; Benedetti, Yanina; Rocchi, Marco; Canestrari, Franco

    2009-03-01

    Vitamin B12 is a critical nutrient that is often inadequate in a plant-based (vegan) diet, thus the inclusion of a reliable vitamin B12 source in a vegan diet is recommended as essential. Unfortunately, many natural sources of vitamin B12 have been proven to contain biologically inactive vitamin B12 analogues, inadequate for human supplementation. The aim of this non-randomized open trial was to determine whether supplementation with a natural Klamath algae-based product ("AFA-B12", Aphanizomenon flos-aquae algae plus a proprietary mix of enzymes) could favorably affect the vitamin B12 status of a group of 15 vegan subjects. By assessing blood concentration of vitamin B12, folate, and more importantly homocysteine (Hcy, a reliable marker in vegans of their B12 absorption), the vitamin B12 status of the participants at the end of the 3-month intervention period, while receiving the Klamath-algae supplement (T2), was compared with their vitamin B12 status at the end of the 3-month control period (T1), when they were not receiving any supplement, having stopped taking their usual vitamin B12 supplement at the beginning of the study (T0). Compared to the control period, in the intervention period participants improved their vitamin B12 status, significantly reducing Hcy blood concentration (p=0.003). In conclusion, the Klamath algae product AFA-B12 appears to be, in a preliminary study, an adequate and reliable source of vitamin B12 in humans.

  15. Low-dimensional boron structures based on icosahedron B12

    NASA Astrophysics Data System (ADS)

    Kah, C. B.; Yu, M.; Tandy, P.; Jayanthi, C. S.; Wu, S. Y.

    2015-10-01

    One-dimensional icosahedral boron chains and two-dimensional icosahedral boron sheets (icosahedral α, δ6, and δ4 sheets) that contain icosahedra B12 as their building units have been predicted in a computer simulation study using a state-of-the-art semi-empirical Hamiltonian. These novel low-dimensional icosahedral structures exhibit interesting bonding and electronic properties. Specifically, the three-center, two-electron bonding between icosahedra B12 of the boron bulk (rhombohedral boron) transforms into a two-center bonding in these new allotropes of boron sheets. In contrast to the previously reported stable buckled α and triangular boron monolayer sheets, these new allotropes of boron sheets form a planar network. Calculations of electronic density of states (DOS) reveal a semiconducting nature for both the icosahedral chain and the icosahedral δ6 and δ4 sheets, as well as a nearly gapless (or metallic-like) feature in the DOS for the icosahedral α sheet. The results for the energy barrier per atom between the icosahedral δ6 and α sheets (0.17 eV), the icosahedral δ6 and δ4 sheets (0.38 eV), and the icosahedral α and δ4 sheets (0.27 eV), as indicated in the respective parentheses, suggest that these new allotropes of boron sheets are relatively stable.

  16. Holotranscobalamin (HoloTC, Active-B12) and Herbert's model for the development of vitamin B12 deficiency: a review and alternative hypothesis.

    PubMed

    Golding, Paul Henry

    2016-01-01

    The concentration of total vitamin B12 in serum is not a sufficiently sensitive or specific indicator for the reliable diagnosis of vitamin B12 deficiency. Victor Herbert proposed a model for the staged development of vitamin B12 deficiency, in which holotranscobalamin (HoloTC) is the first indicator of deficiency. Based on this model, a commercial immunoassay has been controversially promoted as a replacement for the total vitamin B12 test. HoloTC is cobalamin (vitamin B12) attached to the transport protein transcobalamin, in the serum, for delivery to cells for metabolism. Although there have been many published reports supporting the claims for HoloTC, the results of some studies were inconsistent with the claim of HoloTC as the most sensitive marker of vitamin B12 deficiency. This review examines the evidence for and against the use of HoloTC, and concludes that the HoloTC immunoassay cannot be used to measure vitamin B12 status any more reliably than total vitamin B12, or to predict the onset of a metabolic deficiency, because it is based on an erroneous hypothesis and a flawed model for the staged development of vitamin B12 deficiency. The author proposes an alternative model for the development of vitamin B12 deficiency.

  17. Prothymosin-α Variants Elicit Anti-HIV-1 Response via TLR4 Dependent and Independent Pathways

    PubMed Central

    Gusella, G. Luca; Teixeira, Avelino; Aberg, Judith; Uversky, Vladimir N.; Mosoian, Arevik

    2016-01-01

    Background Prothymosin α (ProTα) (isoform 2: iso2) is a widely distributed, small acidic protein with intracellular and extracellular-associated functions. Recently, we identified two new ProTα variants with potent anti-HIV activity from CD8+ T cells and cervicovaginal lavage. The first is a splice variant of the ProTα gene known as isoB and the second is the product of ProTα pseudogene 7 (p7). Similarly to iso2, the anti-HIV activity of both variants is mediated by type I IFN. Here we tested whether the immunomodulatory activity of isoB and p7 are also TLR4 dependent and determined their kinetic of release in response to HIV-1 infection. Methods Type I, type III, TNF-α and IL-6 mRNA inducing activity was determined in macrophages from wild type and TLR4 knockout mice treated with recombinant ProTα variants. Supernatants from mock and HIV infected cells were analyzed by mass spectrometry in positive and negative modes for the presence of ProTα variants. In silico structural and functional analysis of ProTα variants were performed. Results We show that both isoB and p7 upregulate IFN-β, IFN-λ1, IL-6, TNF-α and RANTES mRNAs in primary human macrophages. The potent stimulation of IFN-β by the recombinant ProTα variants in human macrophages is dependent on the TLR4 pathway, whereas the induction of TNF-α and IL-6 may also occur independently of TLR4, suggesting the interaction of ProTα variants with other signaling molecules/receptors. In silico analyses confirmed that the novel isoB and p7 variants are intrinsically disordered proteins, which lack the NLS and mass spectrometry showed release of ProTα variants within minutes post HIV-1 infection. These features are consistent with the function of ProTα variants as damage associate molecular patterns (DAMPs). Conclusions Our findings indicate that ProTα variants strongly inhibit viral replication mainly, but not exclusively, through TLR4 signaling and that they are released within minutes of viral

  18. The role of Vitamin B12 in the critically ill--a review.

    PubMed

    Romain, M; Sviri, S; Linton, D M; Stav, I; van Heerden, P V

    2016-07-01

    Vitamin B12 is an essential micronutrient, as humans have no capacity to produce the vitamin and it needs to be ingested from animal proteins. The ingested Vitamin B12 undergoes a complex process of absorption and assimilation. Vitamin B12 is essential for cellular function. Deficiency affects 15% of patients older than 65 and results in haematological and neurological disorders. Low levels of Vitamin B12 may also be an independent risk factor for coronary artery disease. High levels of Vitamin B12 are associated with inflammation and represent a poor outlook for critically ill patients. Treatment of Vitamin B12 deficiency is simple, but may be lifelong.

  19. Synthesis and anti-HIV activity of thiocholesteryl-coupled phosphodiester antisense oligonucleotides incorporated into immunoliposomes.

    PubMed

    Zelphati, O; Wagner, E; Leserman, L

    1994-09-01

    Encapsulation of oligonucleotides in antibody-targeted liposomes (immunoliposomes) which bind to target cells permits intracellular delivery of the oligonucleotides. This approach circumvents problems of extracellular degradation by nucleases and poor membrane permeability which free phosphodiester oligonucleotides are subject to, but leaves unresolved the inefficiency of encapsulation of oligonucleotides in liposomes. We have coupled oligonucleotides to cholesterol via a reversible disulfide bond. This modification of oligonucleotides improved their association with immunoliposomes by a factor of about 10 in comparison to unmodified oligonucleotides. The presence of cholesteryl-modified oligonucleotides incorporated in the bilayer of liposomes did not interfere with the coupling of the targeting protein to the liposome surface. Free or cholesterol coupled oligonucleotides associated with liposomes and directed against the tat gene of HIV-1 were tested for inhibition of HIV-1 proliferation in acutely infected cells. We demonstrate that the cholesteryl-modified as well as unmodified oligonucleotides acquire the target specificity of the antibody on the liposome. Their antiviral activity when delivered into cells is sequence-specific. The activity of these modified or unmodified oligonucleotides to inhibit the replication of HIV was the same on an equimolar basis (EC50 around 0.1 microM). Cholesterol coupled oligonucleotides thus offer increased liposome association without loss of antiviral activity.

  20. Structure-activity relationship study of pyrimido[1,2-c][1,3]benzothiazin-6-imine derivatives for potent anti-HIV agents.

    PubMed

    Mizuhara, Tsukasa; Oishi, Shinya; Ohno, Hiroaki; Shimura, Kazuya; Matsuoka, Masao; Fujii, Nobutaka

    2012-11-01

    3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182) is an antiretroviral agent with submicromolar inhibitory activity against human immunodeficiency virus-1 (HIV-1) and HIV-2 infection. In the current study, the structure-activity relationships of accessory groups at the 3- and 9-positions of pyrimido[1,2-c][1,3]benzothiazin-6-imine were investigated for the development of more potent anti-HIV agents. Several different derivatives containing a 9-aryl group were designed and synthesized using Suzuki-Miyaura cross-coupling and Ullmann coupling reactions. Modification of the m-methoxyphenyl or benzo[d][1,3]dioxol-5-yl group resulted in improved anti-HIV activity. In addition, the 2,4-diazaspiro[5.5]undec-2-ene-fused benzo[e][1,3]thiazine derivatives were designed and tested for their anti-HIV activities. The most potent 9-(benzo[d][1,3]dioxol-5-yl) derivative was two-threefold more effective against several strains of HIV-1 and HIV-2 than the parent compound, PD 404182.

  1. Inhibition of clinical human immunodeficiency virus (HIV) type 1 isolates in primary CD4+ T lymphocytes by retroviral vectors expressing anti-HIV genes.

    PubMed Central

    Vandendriessche, T; Chuah, M K; Chiang, L; Chang, H K; Ensoli, B; Morgan, R A

    1995-01-01

    Gene therapy may be of benefit in human immunodeficiency virus type 1 (HIV-1)-infected individuals by virtue of its ability to inhibit virus replication and prevent viral gene expression. It is not known whether anti-HIV-1 gene therapy strategies based on antisense or transdominant HIV-1 mutant proteins can inhibit the replication and expression of clinical HIV-1 isolates in primary CD4+ T lymphocytes. We therefore transduced CD4+ T lymphocytes from uninfected individuals with retroviral vectors expressing either HIV-1-specific antisense-TAR or antisense-Tat/Rev RNA, transdominant HIV-1 Rev protein, and a combination of antisense-TAR and transdominant Rev. The engineered CD4+ T lymphocytes were then infected with four different clinical HIV-1 isolates. We found that replication of all HIV-1 isolates was inhibited by all the anti-HIV vectors tested. Greater inhibition of HIV-1 was observed with transdominant Rev than with antisense RNA. We hereby demonstrated effective protection by antisense RNA or transdominant mutant proteins against HIV-1 infection in primary CD4+ T lymphocytes using clinical HIV-1 isolates, and this represents an essential step toward clinical anti-HIV-1 gene therapy. PMID:7769662

  2. Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency.

    PubMed

    Hannibal, Luciana; Lysne, Vegard; Bjørke-Monsen, Anne-Lise; Behringer, Sidney; Grünert, Sarah C; Spiekerkoetter, Ute; Jacobsen, Donald W; Blom, Henk J

    2016-01-01

    Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of <200 pmol/L) presents asymptomatically or with rather subtle generic symptoms that oftentimes are mistakenly ascribed to unrelated disorders. Numerous studies have now established that serum vitamin B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders.

  3. Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency

    PubMed Central

    Hannibal, Luciana; Lysne, Vegard; Bjørke-Monsen, Anne-Lise; Behringer, Sidney; Grünert, Sarah C.; Spiekerkoetter, Ute; Jacobsen, Donald W.; Blom, Henk J.

    2016-01-01

    Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of <200 pmol/L) presents asymptomatically or with rather subtle generic symptoms that oftentimes are mistakenly ascribed to unrelated disorders. Numerous studies have now established that serum vitamin B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders. PMID:27446930

  4. Bicyclams, a class of potent anti-HIV agents, are targeted at the HIV coreceptor fusin/CXCR-4.

    PubMed

    Schols, D; Esté, J A; Henson, G; De Clercq, E

    1997-08-01

    Bicyclams are a novel class of antiviral compounds which are highly potent and selective inhibitors of the replication of HIV-1 and HIV-2. The prototype compound, AMD3100, has an IC50 of 1-10 ng/ml, which is a least 100,000 fold lower than the cytotoxic concentration. AMD3100 does not inhibit virus binding to the CD4 receptor and based on time-of-addition experiments, has been assumed to interact with the HIV fusion-uncoating process. Resistance of HIV-1 strains to AMD3100 is associated with the accumulation of several mutations in the viral envelope glycoprotein gp120. Here, we demonstrate that AMD3100 interacts with fusin (CXCR-4), the coreceptor used by T-tropic viruses to infect the target cells. The replication of NL4-3 wild type virus and NL4-3 dextran sulfate-resistant virus was inhibited by the CXC-chemokine, stromal cell-derived factor 1 (SDF-1), the natural ligand for CXCR-4. In contrast, the replication of the HIV-1 NL4-3 AMD3100-resistant virus was no longer inhibited by SDF-1. The bicyclams are the first low-molecular-weight anti-HIV agents shown to interact with the coreceptor for T-tropic viruses.

  5. Development and characterization of a solid dispersion film for the vaginal application of the anti-HIV microbicide UAMC01398.

    PubMed

    Grammen, Carolien; Van den Mooter, Guy; Appeltans, Bernard; Michiels, Johan; Crucitti, Tania; Ariën, Kevin K; Augustyns, Koen; Augustijns, Patrick; Brouwers, Joachim

    2014-11-20

    The purpose of this work was to design and evaluate a vaginal film delivery system for UAMC01398, a novel non-nucleoside reverse transcriptase inhibitor currently under investigation for use as an anti-HIV microbicide. UAMC01398 (1mg) films consisting of hydroxypropylmethylcellulose (HPMC) and polyethylene glycol 400 (PEG400) in different ratios were prepared by solvent evaporation. Based on its flexibility, softness and translucent appearance, the 30% PEG400 and 70% HPMC containing film was selected for further assessment. The vaginal film formulation was fast-dissolving (<10 min in 1 mL of vaginal fluid simulant), stable up to at least one month and safe toward epithelial cells and lactobacilli. Furthermore, formulating UAMC01398 into the film dosage form did not influence its antiviral activity. Powder X-ray diffraction revealed the amorphous nature of the UAMC01398 film, resulting in enhanced compound permeation across the epithelial HEC-1A cell layer, presumably owing to the induction of supersaturation. The in vivo vaginal tissue uptake of UAMC01398 in rabbits, as measured by systemic concentrations, was increased compared to the previously established non-solubilizing gel (significant difference) and sulfobutyl ether-β-cyclodextrin (5%) containing gel. To conclude, we identified a film formulation suitable for the vaginal delivery of UAMC01398.

  6. [Anti-HIV effects of IFN-tau in human macrophages: role of cellular antiviral factors and interleukin-6].

    PubMed

    Maneglier, B; Rogez-Kreuz, C; Dereuddre-Bosquet, N; Martal, J; Devillier, P; Dormont, D; Clayette, P

    2008-01-01

    Tau interferon (IFN-tau) was shown to inhibit human immunodeficiency virus (HIV) replication in vitro more strongly than human IFN-alpha, particularly in human macrophages. IFN-tau efficiently inhibited the early steps of HIV biological cycle, decreasing intracellular HIV RNA and inhibiting the initiation of the reverse transcription of viral RNA into proviral DNA. In this study, the in vitro immunomodulatory effects of IFN-tau were explored in human macrophages. We found that IFN-tau increased the synthesis of the cellular antiviral factors, such as 2',5'-oligoadenylate synthetase/RNase L and MxA protein. These results suggested that IFN-tau induces the same antiviral pathways in macrophages as other type I IFNs. We found that IFN-tau increased the production of interleukins (IL)-10 and IL-6, but not of IL-1ss or TNF-alpha, in not infected and in in vitro HIV-1/Ba-L-infected macrophages. We also found that the neutralization of IL-6 biological activity in the cell culture supernatants of IFN-tau-treated macrophages led to a decrease in the antiretroviral effects of IFN-tau towards HIV RNA. In conclusion, anti-HIV effects of IFN-tau are mediated by several modes of action, mediated either directly by IFN-tau or via other cytokines, such as IL-6, also known to be induced by IFN-alpha.

  7. DNA topoisomerase IIα inhibitory and anti-HIV-1 flavones from leaves and twigs of Gardenia carinata.

    PubMed

    Kongkum, Naowarat; Tuchinda, Patoomratana; Pohmakotr, Manat; Reutrakul, Vichai; Piyachaturawat, Pawinee; Jariyawat, Surawat; Suksen, Kanoknetr; Yoosook, Chalobon; Kasisit, Jitra; Napaswad, Chanita

    2012-03-01

    Four new flavones, 5,2'-dihydroxy-7,3',4',5'-tetramethoxyflavone (1), 5,2',5'-trihydroxy-7,3',4'-trimethoxyflavone (2), 5,7,2',5'-tetrahydroxy-6,3',4'-trimethoxyflavone (3) and 5,2',5'-trihydroxy-6,7,3',4'-tetramethoxyflavone (4), along with the known 5,3'-dihydroxy-6,7,4',5'-tetramethoxyflavone (5), 5,7,3',5'-tetrahydroxy-6,4'-dimethoxyflavone (6), syringaldehyde, vanillic acid and scopoletin were isolated from the leaves and twigs of Gardenia carinata (Rubiaceae). Their structures were determined by spectroscopic methods. Flavone 2 exhibited cytotoxic activity against P-388 and MCF-7 cell lines, while 3, 5 and 6 were active only in P-388 cell line. All active compounds were found to inhibit DNA topoisomerase IIα activity, which may be responsible for the observed cytotoxicity. Flavones 1-3, 5 and 6 also exhibited anti-HIV-1 activity in the anti-syncytium assay using (∆Tat/rev)MC99 virus and 1A2 cell line system; 2 was most potent. Only flavones 1 and 6 showed considerably activity against HIV-1 reverse transcriptase.

  8. Dose-response curve slope sets class-specific limits on inhibitory potential of anti-HIV drugs.

    PubMed

    Shen, Lin; Peterson, Susan; Sedaghat, Ahmad R; McMahon, Moira A; Callender, Marc; Zhang, Haili; Zhou, Yan; Pitt, Eleanor; Anderson, Karen S; Acosta, Edward P; Siliciano, Robert F

    2008-07-01

    Highly active antiretroviral therapy (HAART) can control HIV-1 replication, but suboptimal treatment allows for the evolution of resistance and rebound viremia. A comparative measure of antiviral activity under clinically relevant conditions would guide drug development and the selection of regimens that maximally suppress replication. Here we show that current measures of antiviral activity, including IC(50) and inhibitory quotient, neglect a key dimension, the dose-response curve slope. Using infectivity assays with wide dynamic range, we show that this slope has noteworthy effects on antiviral activity. Slope values are class specific for antiviral drugs and define intrinsic limitations on antiviral activity for some classes. Nucleoside reverse transcriptase inhibitors and integrase inhibitors have slopes of approximately 1, characteristic of noncooperative reactions, whereas non-nucleoside reverse transcriptase inhibitors, protease inhibitors and fusion inhibitors unexpectedly show slopes >1. Instantaneous inhibitory potential (IIP), the log reduction in single-round infectivity at clinical drug concentrations, is strongly influenced by slope and varies by >8 logs for anti-HIV drugs. IIP provides a more accurate measure of antiviral activity and in general correlates with clinical outcomes. Only agents with slopes >1 achieve high-level inhibition of single-round infectivity, a finding with profound implications for drug and vaccine development.

  9. Activation of the human nuclear xenobiotic receptor PXR by the reverse transcriptase-targeted anti-HIV drug PNU-142721

    SciTech Connect

    Cheng, Yuan; Redinbo, Matthew R.

    2012-10-09

    The human pregnane X receptor (PXR) is a member of the nuclear receptor superfamily of ligand-regulated transcription factors. PXR responds to a structurally diverse variety of endogenous and xenobiotic compounds, and coordinates the expression of genes central to the metabolism and excretion of potentially harmful chemicals, including human therapeutics. The reverse transcriptase inhibitor PNU-142721 has been designed to treat human immunodeficiency virus (HIV) infection. Although this compound has anti-HIV activity, it was established using cell-based assays that PNU-142721 is an efficacious PXR agonist. We present here the 2.8 {angstrom} resolution crystal structure of the human PXR ligand-binding domain in complex with PNU-142721. PXR employs one hydrogen bond and fourteen van der Waals contacts to interact with the ligand, but allows two loops adjacent to the ligand-binding pocket to remain disordered in the structure. These observations highlight the role structural flexibility plays in PXR's promiscuous responses to xenobiotics. The crystal structure also explains why PNU-173575, a thiomethyl metabolite of PNU-142721, exhibits enhanced PXR activation relative to the unmodified compound and why PNU-142721 can also activate rat PXR. Taken together, the results presented here elucidate the structural basis for PXR activation by PNU-142721 and related chemicals.

  10. A novel family of diarylpyrimidines (DAPYs) featuring a diatomic linker: Design, synthesis and anti-HIV activities.

    PubMed

    Gu, Shuang-Xi; Qiao, Heng; Zhu, Yuan-Yuan; Shu, Qi-Chao; Liu, Hui; Ju, Xiu-Lian; De Clercq, Erik; Balzarini, Jan; Pannecouque, Christophe

    2015-10-15

    To improve the conformational flexibility and positional adaptability of the traditional diarylpyrimidines (DAPYs), a family of diarylpyrimidines featuring a C-N diatomic linker between the left wing benzene ring and the central pyrimidine was firstly designed, synthesized, and evaluated for in vitro anti-HIV activity. Most of target molecules showed excellent activities against wild-type (WT) HIV-1. Among them the most potent two compounds 12h and 12r displayed extremely potent WT HIV-1 inhibitory activities with an EC50 of 2.6 nM and 3.0 nM, respectively, while their selective index (CC50/EC50) values were both over 1000. Another compound 12b (EC50 14.9 nM) was also noteworthy due to its high SI of 18,614. Moreover, all of compounds were evaluated for their WT HIV-1 reverse transcriptase activities, which shown that the newly synthesized CH2NH-DAPYs bind to HIV-1 RT and belong to the genuine NNRTIs. However, the synthesized compounds lack the activities against HIV-1 double mutant (RES056) and HIV-2 (ROD). Thus it is an upcoming objective to improve the activities against HIV-1 double mutants.

  11. Exosomes contribute to the transmission of anti-HIV activity from TLR3-activated brain microvascular endothelial cells to macrophages

    PubMed Central

    Sun, Li; Wang, Xu; Zhou, Yu; Zhou, Run-Hong; Ho, Wen-Zhe; Li, Jie-Liang

    2017-01-01

    Human brain microvascular endothelial cells (HBMECs), the major cell type in the blood-brain barrier (BBB), play a key role in maintaining brain homeostasis. However, their role in the BBB innate immunity against HIV invasion of the central nervous system (CNS) remains to be determined. Our early work showed that TLR3 signaling of HBMECs could produce the antiviral factors that inhibit HIV replication in macrophages. The present study examined whether exosomes from TLR3-activated HBMECs mediate the intercellular transfer of antiviral factors to macrophages. Primary human macrophages could take up exosomes from TLR3-activated HBMECs. HBMECs-derived exosomes contained multiple antiviral factors, including several key IFN-stimulated genes (ISGs; ISG15, ISG56, and Mx2) at mRNA and protein levels. The depletion of exosomes from TLR3-activated HBMECs culture supernatant diminished HBMECs-mediated anti-HIV activity in macrophages. In conclusion, we demonstrate that exosomes shed by HBMECs are able to transport the antiviral molecules to macrophages. This finding suggests the possibility that HIV nonpermissive BBB cells (HBMECs) can help to restore the antiviral state in HIV-infected macrophages, which may be a defense mechanism against HIV neuroinvasion. PMID:27496004

  12. Host Anti-antibody Responses Following Adeno-associated Virus-mediated Delivery of Antibodies Against HIV and SIV in Rhesus Monkeys.

    PubMed

    Martinez-Navio, José M; Fuchs, Sebastian P; Pedreño-López, Sònia; Rakasz, Eva G; Gao, Guangping; Desrosiers, Ronald C

    2016-02-01

    Long-term delivery of antibodies against the human immunodeficiency virus (HIV) using adeno-associated virus (AAV) vectors is a promising approach for the prevention or treatment of HIV infection. However, host antibody responses to the delivered antibody are a serious concern that could significantly limit the applicability of this approach. Here, we describe the dynamics and characteristics of the anti-antibody responses in monkeys that received either rhesus anti-simian immunodeficiency virus (SIV) antibodies (4L6 or 5L7) in prevention trials or a combination of rhesusized human anti-HIV antibodies (1NC9/8ANC195/3BNC117 or 10-1074/10E8/3BNC117) in therapy trials, all employing AAV1 delivery of IgG1. Eight out of eight monkeys that received the anti-HIV antibodies made persisting antibody responses to all three antibodies in the mix. Six out of six uninfected monkeys that received the anti-SIV antibody 4L6 and three out of six of those receiving anti-SIV antibody 5L7 also generated anti-antibodies. Both heavy and light chains were targeted, predominantly or exclusively to variable regions, and reactivity to complementarity-determining region (CDR)-H3 peptide could be demonstrated. There was a highly significant correlation of the magnitude of anti-antibody responses with the degree of sequence divergence of the delivered antibody from germline. Our results suggest the need for effective strategies to counteract the problem of antibody responses to AAV-delivered antibodies.

  13. WHI-05, a novel bromo-methoxy substituted phenyl phosphate derivative of zidovudine, is a dual-action spermicide with potent anti-HIV activity.

    PubMed

    D'Cruz, O J; Zhu, Z; Yiv, S H; Chen, C L; Waurzyniak, B; Uckun, F M

    1999-05-01

    Heterosexual transmission of HIV to women is the fastest-growing mode of transmission. In a systematic effort to develop a microbicide capable of preventing HIV transmission as well as providing fertility control, novel phenyl phosphate derivatives of 3'-azido-3'-deoxythymidine (zidovudine, ZDV) have been identified that exhibit potent anti-HIV and spermicidal activities. This study reports the synthesis, characterization, and preclinical formulation of compound WHI-05, 5-bromo-6-methoxy-5,6-dihydro-3'-azidothymidine-5'-(p-methoxyphenyl) methoxyalaninyl phosphate. The anti-HIV activities of WHI-05 and ZDV were compared by measuring p24 antigen production and reverse transcriptase activity as markers of viral replication using human peripheral blood mononuclear cells (PBMC) infected with both ZDV-sensitive and ZDV-resistant strains of HIV. The sperm immobilizing activity (SIA) of WHI-05 was compared with that of ZDV and nonoxynol-9 (N-9) by computer-assisted sperm analysis (CASA). The effect of WHI-05 on sperm membrane integrity was examined by high resolution, low voltage scanning electron microscopy (HR-LVSEM). The in vitro cytotoxicity profile of WHI-05 versus N-9 were compared using normal human vaginal, ectocervical, and endocervical epithelial cells. The in vivo vaginal tolerance, absorption, and toxicity of a 2% WHI-05 gel-microemulsion was tested in the rabbit. Whereas ZDV displayed potent anti-HIV activity but lacked SIA, WHI-05 elicited both potent anti-HIV activity and SIA. WHI-05 inhibited the replication of ZDV-sensitive as well as ZDV-resistant strains of HIV in PBMC. CASA combined with HR-LVSEM demonstrated that WHI-05-induced SIA was not associated with membrane damage. Unlike, N-9, the spermicidal activity of WHI-05 was not associated with cytotoxicity to reproductive tract epithelial cells. Repetitive intravaginal application of a 2% WHI-05 gel-microemulsion did not damage the vaginal epithelium or cause local inflammation in the rabbit model. As a

  14. Glossitis with linear lesions: an early sign of vitamin B12 deficiency.

    PubMed

    Graells, Jordi; Ojeda, Rosa Maria; Muniesa, Cristina; Gonzalez, Jesus; Saavedra, Jose

    2009-03-01

    The classic oral manifestations of vitamin B(12) deficiency are considered nonspecific. We describe 4 patients with oral linear lesions associated with vitamin B(12) deficiency. Patients were free of neurologic symptoms and anemia at diagnosis. We believe that glossitis with linear lesions is an early clinical sign of vitamin B(12) deficiency. We recommend the determination of vitamin B(12) in such patients, even in the absence of anemia.

  15. Vitamin B-12 supplementation during pregnancy and early lactation increases maternal, breast milk, and infant measures of vitamin B-12 status.

    PubMed

    Duggan, Christopher; Srinivasan, Krishnamachari; Thomas, Tinku; Samuel, Tinu; Rajendran, Ramya; Muthayya, Sumithra; Finkelstein, Julia L; Lukose, Ammu; Fawzi, Wafaie; Allen, Lindsay H; Bosch, Ronald J; Kurpad, Anura V

    2014-05-01

    Pregnant women in resource-poor areas are at risk of multiple micronutrient deficiencies, and indicators of low vitamin B-12 status have been associated with adverse pregnancy outcomes, including anemia, low birth weight, and intrauterine growth retardation. To evaluate whether daily oral vitamin B-12 supplementation during pregnancy increases maternal and infant measures of vitamin B-12 status, we performed a randomized, placebo-controlled clinical trial. Pregnant women <14 wk of gestation in Bangalore, India, were randomly assigned to receive daily oral supplementation with vitamin B-12 (50 μg) or placebo through 6 wk postpartum. All women were administered iron and folic acid supplements throughout pregnancy. One hundred eighty-three women were randomly assigned to receive vitamin B-12 and 183 to receive placebo. Compared with placebo recipients, vitamin B-12-supplemented women had significantly higher plasma vitamin B-12 concentrations at both the second (median vitamin B-12 concentration: 216 vs. 111 pmol/L, P < 0.001) and third (median: 184 vs. 105 pmol/L, P < 0.001) trimesters. At 6 wk postpartum, median breast milk vitamin B-12 concentration was 136 pmol/L in vitamin B-12-supplemented women vs. 87 pmol/L in the placebo group (P < 0.0005). Among vitamin B-12-supplemented women, the incidence of delivering an infant with intrauterine growth retardation was 33 of 131 (25%) vs. 43 of 125 (34%) in those administered placebo (P = 0.11). In a subset of infants tested at 6 wk of age, median plasma vitamin B-12 concentration was 199 pmol/L in those born to supplemented women vs. 139 pmol/L in the placebo group (P = 0.01). Infant plasma methylmalonic acid and homocysteine concentrations were significantly lower in the vitamin B-12 group as well. Oral supplementation of urban Indian women with vitamin B-12 throughout pregnancy and early lactation significantly increases vitamin B-12 status of mothers and infants. It is important to determine whether there are

  16. Vitamin B-12 supplementation of rural Mexican women changes biochemical vitamin B-12 status indicators but does not affect hematology or a bone turnover marker.

    PubMed

    Shahab-Ferdows, Setareh; Anaya-Loyola, Miriam A; Vergara-Castañeda, Haydé; Rosado, Jorge L; Keyes, William R; Newman, John W; Miller, Joshua W; Allen, Lindsay H

    2012-10-01

    A high prevalence of low serum vitamin B-12 concentrations has been reported in studies and surveys in Latin America including Mexico, but the functional consequences are unknown. This randomized controlled trial assessed the response to a high-dose vitamin B-12 supplementation of women in rural Querétaro, Mexico. Participants aged 20-59 y were stratified at baseline to deficient, marginal, and adequate status groups (serum vitamin B-12, 75-148, 149-220, and >220 pmol/L, respectively), and each group was randomized to vitamin B-12 treatment (single dose of 1 mg i.m. then 500 μg/d orally for 3 mo, n = 70) or placebo (n = 62). Measures at baseline and 3 mo included: complete blood count, serum vitamin B-12, holotranscobalamin (holoTC), folate, ferritin, C-reactive protein (CRP), bone alkaline phosphatase, and methylmalonic acid (MMA) and plasma total homocysteine (tHcy). At baseline, 11% of the women were vitamin B-12 deficient and 22% had marginal status. HoloTC was low (<35 pmol/L) in 23% and correlated with serum vitamin B-12 (r = 0.7; P < 0.001). Elevated MMA (>271 nmol/L) and tHcy (>12 μmol/L) occurred in 21 and 31%, respectively, and correlated with serum vitamin B-12 (r = -0.28, P < 0.0007 and r = -0.20, P < 0.01, respectively). Supplementation increased serum vitamin B-12 and holoTC and lowered MMA and tHcy, normalizing all values except for elevated tHcy in 21% of the women. Supplementation did not affect hematology or bone-specific alkaline phosphatase. Vitamin B-12 supplementation normalized biochemical indicators of vitamin B-12 status in the treatment group but did not affect the functional outcomes measured.

  17. Neutralizing Monoclonal Antibodies to Fight HIV-1: On the Threshold of Success

    PubMed Central

    Jaworski, Juan Pablo; Vendrell, Alejandrina; Chiavenna, Sebastián Matias

    2017-01-01

    Anti-human immunodeficiency virus type-1 (anti-HIV-1) neutralizing monoclonal antibodies are broadening the spectrum of pre- and post-exposure treatment against HIV-1. A better understanding of how these antibodies develop and interact with particular regions of the viral envelope protein is guiding a more rational structure-based immunogen design. The aim of this article is to review the most recent advances in the field, from the development of these particular antibodies during natural HIV-1 infection, to their role preventing infection, boosting endogenous immune responses and clearing both free viral particles and persistently infected cells. PMID:28123384

  18. 12 CFR 261b.12 - Procedures for inspection and obtaining copies of transcriptions and minutes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... of transcriptions and minutes. 261b.12 Section 261b.12 Banks and Banking FEDERAL RESERVE SYSTEM... § 261b.12 Procedures for inspection and obtaining copies of transcriptions and minutes. (a) Any person may inspect or copy a transcript, a recording or transcription of a recording, or minutes described...

  19. 12 CFR 261b.12 - Procedures for inspection and obtaining copies of transcriptions and minutes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... of transcriptions and minutes. 261b.12 Section 261b.12 Banks and Banking FEDERAL RESERVE SYSTEM... OF MEETINGS § 261b.12 Procedures for inspection and obtaining copies of transcriptions and minutes. (a) Any person may inspect or copy a transcript, a recording or transcription of a recording,...

  20. 12 CFR 261b.12 - Procedures for inspection and obtaining copies of transcriptions and minutes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... of transcriptions and minutes. 261b.12 Section 261b.12 Banks and Banking FEDERAL RESERVE SYSTEM... OF MEETINGS § 261b.12 Procedures for inspection and obtaining copies of transcriptions and minutes. (a) Any person may inspect or copy a transcript, a recording or transcription of a recording,...

  1. 42 CFR 52b.12 - What are the minimum requirements of construction and equipment?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false What are the minimum requirements of construction and equipment? 52b.12 Section 52b.12 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.12 What are the...

  2. 42 CFR 52b.12 - What are the minimum requirements of construction and equipment?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false What are the minimum requirements of construction and equipment? 52b.12 Section 52b.12 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.12 What are the...

  3. 42 CFR 52b.12 - What are the minimum requirements of construction and equipment?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false What are the minimum requirements of construction and equipment? 52b.12 Section 52b.12 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.12 What are the...

  4. 12 CFR 261b.12 - Procedures for inspection and obtaining copies of transcriptions and minutes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Procedures for inspection and obtaining copies of transcriptions and minutes. 261b.12 Section 261b.12 Banks and Banking FEDERAL RESERVE SYSTEM... § 261b.12 Procedures for inspection and obtaining copies of transcriptions and minutes. (a) Any...

  5. 12 CFR 261b.12 - Procedures for inspection and obtaining copies of transcriptions and minutes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Procedures for inspection and obtaining copies of transcriptions and minutes. 261b.12 Section 261b.12 Banks and Banking FEDERAL RESERVE SYSTEM... OF MEETINGS § 261b.12 Procedures for inspection and obtaining copies of transcriptions and...

  6. Biologically active vitamin B12 compounds in foods for preventing deficiency among vegetarians and elderly subjects.

    PubMed

    Watanabe, Fumio; Yabuta, Yukinori; Tanioka, Yuri; Bito, Tomohiro

    2013-07-17

    The usual dietary sources of vitamin B12 are animal-source based foods, including meat, milk, eggs, fish, and shellfish, although a few plant-based foods such as certain types of dried lavers (nori) and mushrooms contain substantial and considerable amounts of vitamin B12, respectively. Unexpectedly, detailed characterization of vitamin B12 compounds in foods reveals the presence of various corrinoids that are inactive in humans. The majority of edible blue-green algae (cyanobacteria) and certain edible shellfish predominately contain an inactive corrinoid known as pseudovitamin B12. Various factors affect the bioactivity of vitamin B12 in foods. For example, vitamin B12 is partially degraded and loses its biological activity during cooking and storage of foods. The intrinsic factor-mediated gastrointestinal absorption system in humans has evolved to selectively absorb active vitamin B12 from naturally occurring vitamin B12 compounds, including its degradation products and inactive corrinoids that are present in daily meal foods. The objective of this review is to present up-to-date information on various factors that can affect the bioactivity of vitamin B12 in foods. To prevent vitamin B12 deficiency in high-risk populations such as vegetarians and elderly subjects, it is necessary to identify plant-source foods that contain high levels of bioactive vitamin B12 and, in conjunction, to prepare the use of crystalline vitamin B12-fortified foods.

  7. VITAMIN B-12 SUPPLEMENTATION OF DEFICIENT LACTATING GUATEMALAN WOMEN IMPROVES MATERNAL BUT NOT INFANT STATUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin B-12 deficiency is common in mothers and infants where maternal intake of animals source foods is low. The first six months post-partum is a critical period of neurological development requiring vitamin B-12. A pilot study was designed to determine the dose of B-12 to the mothers that would ...

  8. Vitamin B(12) incorporated with multiwalled carbon nanotube composite film for the determination of hydrazine.

    PubMed

    Umasankar, Yogeswaran; Huang, Tzu-Yen; Chen, Shen-Ming

    2011-01-15

    Electrochemically active composite film containing multiwalled carbon nanotubes (MWCNTs) and vitamin B(12) was synthesized on glassy carbon, gold, and indium tin oxide electrodes by the potentiodynamic method. The presence of MWCNTs in the composite film (MWCNT-B(12)) modified electrode mediates vitamin B(12)'s redox reaction, whereas vitamin B(12)'s redox reaction does not occur at bare electrode. The electrochemical impedance spectroscopy studies reveal that MWCNTs present in MWCNT-B(12) film enhance electron shuttling between the reactant and electrode surface. The surface morphology of bare electrode, MWCNT film. and MWCNT-B(12) composite film was studied using atomic force microscopy, which reveals vitamin B(12) incorporated with MWCNTs. The MWCNT-B(12) composite film exhibits promising enhanced electrocatalysis toward hydrazine. The electrocatalysis response of hydrazine at MWCNT film and MWCNT-B(12) composite film was measured using cyclic voltammetry and amperometric current-time (i-t) curve techniques. The linear concentration range of hydrazine obtained at MWCNT-B(12) composite film using the i-t curve technique is 2.0 μM-1.95 mM. Similarly, the sensitivity of MWCNT-B(12) composite film for hydrazine determination using the i-t curve technique is 1.32 mA mM(-1)cm(-2), and the hydrazine's limit of detection at MWCNT-B(12) composite film is 0.7 μM.

  9. Role of vitamin B12 in depressive disorder--a case report.

    PubMed

    Rao, Naren P; Kumar, Naveen C; Raman, Bhargava R P; Sivakumar, Palanimuthu T; Pandey, Ravi S

    2008-01-01

    Vitamin B12 deficiency anemia may have psychiatric manifestations preceding the hematological symptoms. Although a variety of symptoms are described, there are only sparse data on the role of vitamin B12 in depression. We report a case of vitamin B12 deficiency presenting with recurrent episodes of depression.

  10. Nutrient Acquisition: The Generation of Bioactive Vitamin B12 by Microalgae.

    PubMed

    Grossman, Arthur

    2016-04-25

    Many microalgae acquire vitamin B12 from marine prokaryotes. A new study demonstrates that vitamin B12 is synthesized by planktonic cyanobacteria as pseudocobalamin, a form not bioactive in microalgae. However, some microalgae can remodel pseudocobalamin to the active cobalamin form, adding complexity to our assessment of active vitamin B12 in the environment.

  11. Nitrous oxide–induced vitamin B12 deficiency

    PubMed Central

    Simonsen, Cameron; Seago, Susan

    2017-01-01

    Nitrous oxide is a gas that is odorless, colorless, and has a sweet taste at room temperature. Nitrous oxide has several uses, including in surgery and dentistry (referred to as “laughing gas”), in automotive racing, and in aerosol spray propellants. The aerosol spray propellants that typically use nitrous oxide are whipped cream canisters and cooking sprays. Unfortunately, these over-the-counter household items are a source of nitrous oxide that can be used for recreational use. The most popular is the use of industrial-grade canisters having the slang term “whippets.” The nitrous oxide can be extracted by pushing the nozzle down slightly to the side and catching the released gas with a balloon. The contents of the balloon can then be directly inhaled, giving an instant feeling of euphoria. This is not a benign means to achieve a euphoric state but can cause severe nitrous oxide–induced B12 deficiency, which is presented in this case report.

  12. Vitamin B-12 supplementation of rural Mexican women changes biochemical B-12 status indicators but does not affect hematology or a bone turnover marker

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Based on the high prevalence of low serum vitamin B-12 concentrations and low dietary intake of the vitamin in Latin American studies including research in Mexico, it appears that vitamin B-12 deficiency is common. Whether this is associated with adverse effects on human function is unknown. To eval...

  13. Enhancing the vitamin B12 production and growth of Propionibacterium freudenreichii in tofu wastewater via a light-induced vitamin B12 riboswitch.

    PubMed

    Yu, Yue; Zhu, Xuan; Shen, Yubiao; Yao, Huanghong; Wang, Peiheng; Ye, Kun; Wang, Xiaofeng; Gu, Qing

    2015-12-01

    The vitamin B12-dependent riboswitch is a crucial factor that regulates gene transcription to mediate the growth of and vitamin B12 synthesis by Propionibacterium freudenreichii. In this study, the effect of various wavelengths of light on the growth rate and vitamin B12 synthesis was studied. Red, green, and blue light-emitting diodes (LEDs) were selected, and a dark condition was used as the control. The microorganism growth rate was measured using a spectrophotometer and plate counting, while the vitamin B12 content was determined using an HPLC-based method. The optical density at 600 nm (OD600) values indicated that P. freudenreichii grew better under the continuous and discontinuous blue light conditions. Moreover, under the blue light condition, P. freudenreichii tended to have a higher growth rate (0.332 h(-1)) and vitamin B12 synthesis (ca. 10 μg/mL) in tofu wastewater than in dark conditions. HPLC analysis also showed that more methylcobalamin was produced under the blue light conditions than in the other conditions. The cbiB gene transcription results showed that blue light induced the synthesis of this vitamin B12 synthesis enzyme. Moreover, the results of inhibiting the expression of green fluorescent protein indicated that blue light removed the inhibition by the vitamin B12-dependent riboswitch. This method can be used to reduce fermentation time and produce more vitamin B12 in tofu wastewater.

  14. Proton-pump inhibitor therapy and vitamin B12 status in an inpatient hospital setting.

    PubMed

    Hartman, Brenda; Donnelly-VanderLoo, Mary; Watson, Tiffany; O'Connor, Colleen; Madill, Janet

    2016-06-23

    The risk for impaired vitamin B12 status increases with age, as does the use of proton pump inhibitors (PPI). Long-term use of PPIs is associated with several nutritional deficiencies including B12. Currently, there are no recommendations for B12 screening among patients taking PPIs. Data were abstracted on B12 concentrations, B12-containing supplement use, medications, and select hematological values from a retrospective chart review of 658 adults, 391 with serum B12 concentrations, admitted to 6 different medical units at 2 regional hospitals in Southwestern Ontario between 2010 and 2012. We found no difference between PPI users and nonusers and serum B12 concentrations (404 ± 224 vs 369 ± 213 pmol/L; P = 0.0690). This may be due to use of B12 containing multivitamins in 41% of PPI users. Regression modelling found that aging increases the odds of having an impaired B12 status (<220 pmol/L) by 1.4 times and those using B12 supplements are almost 4 times more likely to have an impaired status. Mean corpuscular volume was not related to B12 status. In this population, older PPI users are more likely to be using multivitamins, which may delay nutritional deficiencies. However, the lower B12 concentrations of PPI users taking only B12 supplements is a concern and requires further research. Finally, physicians need to be aware that mean corpuscular volume is no longer recommended as an effective biomarker for B12 screening and updated screening protocols need to be used to reduce the possibility of adverse neurological effects from impaired B12 status.

  15. Do MCI patients with vitamin B12 deficiency have distinctive cognitive deficits?

    PubMed Central

    2013-01-01

    Background Vitamin B12 deficiency is common in older people, and may be responsible for reversible dementia. Low serum vitamin B12 levels were also observed in patients with Mild Cognitive Impairment (MCI). It is not known whether patients with vitamin B12 deficiency have a distinctive profile of cognitive impairment different from the episodic memory deficit usually observed in MCI. Results From a cohort of 310 patients with MCI followed in a memory clinic in Lisbon, only 10 cases with vitamin B12 deficiency were found. From collaboration with other neurologists, 5 further patients with vitamin B12 deficiency were added. These cases were compared to MCI patients with normal vitamin B12 levels in a ratio 1:3. The duration of subjective cognitive symptoms was significantly shorter in MCI patients with B12 deficiency (1.2±1.0 years) as compared to MCI patients with normal vitamin B12 levels (3.4±3.0 years, p<0.001, Student’ t test). There were no statistically significant differences in the neuropsychological tests between MCI patients with and without vitamin B12 deficiency. Vitamin B12 was started in MCI patients with vitamin B12 deficiency, with no noticeable clinical improvement. Conclusion MCI patients with low levels of vitamin B12 had no particular profile of cognitive impairment, however vitamin B12 deficiency might have precipitated the onset of symptoms. The effect of vitamin B12 supplementation in patients with MCI and low vitamin B12 levels should be clarified by future prospective studies. PMID:24010640

  16. Vitamin B12 and folic acid supplementation and plasma total homocysteine concentrations in pregnant Indian women with low B12 and high folate status.

    PubMed

    Katre, Prachi; Bhat, Dattatray; Lubree, Himangi; Otiv, Suhas; Joshi, Suyog; Joglekar, Charudatta; Rush, Elaine; Yajnik, Chittaranjan

    2010-01-01

    Maternal vitamin B12 deficiency and hyperhomocysteinemia predict poor pregnancy outcome, foetal adiposity and insulin resistance. In India amongst practicing clinicians and policy makers there is little appreciation of widespread vitamin B12 deficiency. We investigated 163 (86 rural, 77 urban) pregnant women attending antenatal clinics in a rural health centre and a referral hospital in the city of Pune, at 17, 28, and 34 weeks gestation for vitamin supplements, and circulating concentrations of vitamin B12, folate, and total homocysteine. At enrolment 80% rural and 65% urban women had low vitamin B12 but only two rural women had low folate concentrations. During pregnancy 85% rural and 95% of urban women received folic acid; 12% rural and 84% urban women also received vitamin B12. In women receiving no supplementation (n=17) plasma vitamin B12 and folate did not change from 17 to 34 weeks gestation, but homocysteine increased (p<0.05). Homocysteine concentrations at 34 weeks gestation in women receiving only folic acid (n=71, mean 8.4 (95% CI 7.8, 9.1) micromol/L) were comparable to the unsupplemented group (9.7 (7.3, 12.7), p=0.15), but women who received a total dose of >1000 microg of vitamin B12 up to 34 weeks (n=42, all with folic acid) had lower concentrations (6.7 (6.0, 7.4), p<0.001). Increasing dose of vitamin B12 (rs=-0.31, p=0.006) but not folic acid (rs=-0.19, p=0.11) was associated with lower plasma total homocysteine concentration. In vitamin B12 insufficient, folate replete pregnant women, vitamin B12 supplementation is associated with a reduction of plasma total homocysteine concentration in late pregnancy.

  17. Hepatoprotective effect of vitamin B12 on dimethylnitrosamine-induced liver injury.

    PubMed

    Isoda, Katsuhiro; Kagaya, Noritaka; Akamatsu, Soichiro; Hayashi, Shinji; Tamesada, Makoto; Watanabe, Aiko; Kobayashi, Masakazu; Tagawa, Yoh-ichi; Kondoh, Masuo; Kawase, Masaya; Yagi, Kiyohito

    2008-02-01

    Vitamin B(12) contains a cobalt complex and accumulates at high levels in the liver. Vitamin B(12) was examined for its hepatoprotective effect on dimethylnitrosamine-induced liver injury in mice. Vitamin B(12) decreased the blood levels of aspartate aminotransferase and alanine aminotransferase, and clearly inhibited the overaccumulation of collagen fibrils. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of the liver showed that the gene expression of alpha-smooth muscle actin and heat-shock protein 47, which are markers of fibrosis, were suppressed by vitamin B(12) administration. Our findings indicate that vitamin B(12) could be an effective hepatoprotective agent.

  18. Vitamin B12 supplementation during pregnancy and postpartum improves B12 status of both mothers and infants but vaccine response in mothers only: a randomized clinical trial in Bangladesh

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose Poor vitamin B12 (B12) status is associated with adverse outcomes in pregnancy and infancy. Little is known about effects of B12 supplementation on immune function. The present study aimed to evaluate effects of pre- and postnatal B12 supplementation on biomarkers of B12 status and vaccine-s...

  19. LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray B12

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray B12 The postflight photograph shows little change of the exposed surfaces when compared with the prelaunch photograph. Although not noticable in the photograph, a light coating of contamination was seen on all experiment surfaces in this location. The difference in colors of the IDE detectors, located on the right hand mounting plate, is a result of the reflected surroundings and not related to space exposure. A close observation of the detector surfaces reveal that some damage has occured from meteroid and/or debris impacts. One impact crater can be seen, upper right quadrant, on the detector located in the sixth (6th) row down from the top and the fifth (5th) row from the right. Other impacts, smaller in size, show as small white dots on the detector surface. The solar sensor seems to have changed little, if any. However, the color of the solar array baseplate, showing indications of contamination, appears to be darker than the detector mounting plate. The center section cover plate shows little change when compared with the pre-launch photograph. However, during inspection, a light coat of the brown contamination has been observed on all surfaces. The color of the bonding material (RTV) used to secure several thin specimen, sapphire, to individual mounting plates has changed from pink to gold. At one location, that of a single specimen, the bonding material is more gray than gold in color. This has been attributed to the specimen being considerably thicker. The EPDS thermal cover in the right hand side of the tray shows a light coating of brown contamination on the Chemglaze II A-276 white paint.

  20. Characterization and Quantitation of Vitamin B12 Compounds in Various Chlorella Supplements.

    PubMed

    Bito, Tomohiro; Bito, Mariko; Asai, Yusuke; Takenaka, Shigeo; Yabuta, Yukinori; Tago, Kazunori; Ohnishi, Masato; Mizoguchi, Toru; Watanabe, Fumio

    2016-11-16

    Vitamin B12 was determined and characterized in 19 dried Chlorella health supplements. Vitamin contents of dried Chlorella cells varied from <0.1 μg to approximately 415 μg per 100 g of dry weight. Subsequent liquid chromatography/electrospray ionization-tandem mass spectrometry analyses showed the presence of inactive corrinoid compounds, a cobalt-free corrinoid, and 5-methoxybenzimidazolyl cyanocobamide (factor IIIm) in four and three high vitamin B12-containing Chlorella tablets, respectively. In four Chlorella tablet types with high and moderate vitamin B12 contents, the coenzyme forms of vitamin B12 5'-deoxyadenosylcobalamin (approximately 32%) and methylcobalamin (approximately 8%) were considerably present, whereas the unnaturally occurring corrinoid cyanocobalamin was present at the lowest concentrations. The species Chlorella sorokiniana (formerly Chlorella pyrenoidosa) is commonly used in dietary supplements and did not show an absolute requirement of vitamin B12 for growth despite vitamin B12 uptake from the medium being observed. In further experiments, vitamin B12-dependent methylmalonyl-CoA mutase and methionine synthase activities were detected in cell homogenates. In particular, methionine synthase activity was significantly increased following the addition of vitamin B12 to the medium. These results suggest that vitamin B12 contents of Chlorella tablets reflect the presence of vitamin B12-generating organic ingredients in the medium or the concomitant growth of vitamin B12-synthesizing bacteria under open culture conditions.

  1. Different Supplementation Regimes to Treat Perioperative Vitamin B12 Deficiencies in Bariatric Surgery: a Systematic Review.

    PubMed

    Smelt, H J M; Pouwels, S; Smulders, J F

    2017-01-01

    Vitamin B12 dosage in multivitamin supplementation in the current literature is quite variable. There is no consensus about the optimal treatment of vitamin B12 deficiency. A systematic literature search on different supplementation regimes to treat perioperative vitamin B12 deficiencies in bariatric surgery was performed. The methodological quality of ten included studies was rated using the Newcastle Ottawa scale and ranged from moderate to good. The agreement between the reviewers was assessed with a Cohen's kappa (0.69). The current literature suggests that 350 μg oral vitamin B12 is the appropriate dose to correct low vitamin B12 levels in many patients. Further research must focus on a better diagnosis of a vitamin B12 deficiency, the optimal dose vitamin B12 supplementation, and clinical relevance next to biochemical data.

  2. Biochemistry, function, and deficiency of vitamin B12 in Caenorhabditis elegans.

    PubMed

    Bito, Tomohiro; Watanabe, Fumio

    2016-09-01

    Caenorhabditis elegans is a nematode that has been widely used as an animal for investigation of diverse biological phenomena. Vitamin B12 is essential for the growth of this worm, which contains two cobalamin-dependent enzymes, methylmalonyl-CoA mutase and methionine synthase. A full complement of gene homologs encoding the enzymes associated with the mammalian intercellular metabolic processes of vitamin B12 is identified in the genome of C elegans However, this worm has no orthologs of the vitamin B12-binders that participate in human intestinal absorption and blood circulation. When the worm is treated with a vitamin B12-deficient diet for five generations (15 days), it readily develops vitamin B12 deficiency, which induces worm phenotypes (infertility, delayed growth, and shorter lifespan) that resemble the symptoms of mammalian vitamin B12 deficiency. Such phenotypes associated with vitamin B12 deficiency were readily induced in the worm.

  3. Biochemistry, function, and deficiency of vitamin B12 in Caenorhabditis elegans

    PubMed Central

    Bito, Tomohiro

    2016-01-01

    Caenorhabditis elegans is a nematode that has been widely used as an animal for investigation of diverse biological phenomena. Vitamin B12 is essential for the growth of this worm, which contains two cobalamin-dependent enzymes, methylmalonyl-CoA mutase and methionine synthase. A full complement of gene homologs encoding the enzymes associated with the mammalian intercellular metabolic processes of vitamin B12 is identified in the genome of C. elegans. However, this worm has no orthologs of the vitamin B12-binders that participate in human intestinal absorption and blood circulation. When the worm is treated with a vitamin B12-deficient diet for five generations (15 days), it readily develops vitamin B12 deficiency, which induces worm phenotypes (infertility, delayed growth, and shorter lifespan) that resemble the symptoms of mammalian vitamin B12 deficiency. Such phenotypes associated with vitamin B12 deficiency were readily induced in the worm. PMID:27486161

  4. Stimulation of Liver X Receptor Has Potent Anti-HIV Effects in a Humanized Mouse Model of HIV Infection

    PubMed Central

    Ramezani, Ali; Dubrovsky, Larisa; Pushkarsky, Tatiana; Sviridov, Dmitri; Karandish, Sara; Raj, Dominic S.; Fitzgerald, Michael L.

    2015-01-01

    Previous studies demonstrated that liver X receptor (LXR) agonists inhibit human immunodeficiency virus (HIV) replication by upregulating cholesterol transporter ATP-binding cassette A1 (ABCA1), suppressing HIV production, and reducing infectivity of produced virions. In this study, we extended these observations by analyzing the effect of the LXR agonist T0901317 [N-[4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenyl]-N-(2,2,2-trifluoroethyl)benzenesulfonamide] on the ongoing HIV infection and investigating the possibility of using LXR agonist for pre-exposure prophylaxis of HIV infection in a humanized mouse model. Pre-exposure of monocyte-derived macrophages to T0901317 reduced susceptibility of these cells to HIV infection in vitro. This protective effect lasted for up to 4 days after treatment termination and correlated with upregulated expression of ABCA1, reduced abundance of lipid rafts, and reduced fusion of the cells with HIV. Pre-exposure of peripheral blood leukocytes to T0901317 provided only a short-term protection against HIV infection. Treatment of HIV-exposed humanized mice with LXR agonist starting 2 weeks postinfection substantially reduced viral load. When eight humanized mice were pretreated with LXR agonist prior to HIV infection, five animals were protected from infection, two had viral load at the limit of detection, and one had viral load significantly reduced relative to mock-treated controls. T0901317 pretreatment also reduced HIV-induced dyslipidemia in infected mice. In conclusion, these results reveal a novel link between LXR stimulation and cell resistance to HIV infection and suggest that LXR agonists may be good candidates for development as anti-HIV agents, in particular for pre-exposure prophylaxis of HIV infection. PMID:26126533

  5. Poly(ethylene glycol) enclatherated pectin-mucin submicron matrices for intravaginal anti-HIV-1 drug delivery.

    PubMed

    Mashingaidze, Felix; Choonara, Yahya E; Kumar, Pradeep; du Toit, Lisa C; Maharaj, Vinesh; Buchmann, Eckhart; Pillay, Viness

    2016-04-30

    This paper explores the potential of polyethylene glycol enclatherated pectin-mucin (PEG-encl-PEC:MUC) submicron matrices (SMMs) as an intravaginal drug delivery system capable of delivering an anti-HIV-1 agent (zidovudine; AZT) over a prolonged duration. A three factor and three level (3(3)) Box-Behnken statistical design was employed to optimize the SMMs. Optimized PEG-encl-PEC:MUC SMMs prepared as a stable W/O emulsion (determined by the degree of reversible colloidal phenomena) were spherical with a mean particle size of 270.6 ± 5.533 nm and mean zeta potential of -34.4 ± 0.539 mV. The microencapsulation of AZT and the hydrogen bonding mediated shielding of AZT by SMMs was confirmed by Fourier Transform Infrared (FTIR) analysis. The thermochemical (differential scanning calorimetry and thermogravimetric analysis) data proposed that Ca(2+)-based macromolecular ionic crosslinking as well as the intermolecular interactions may be responsible for the thermal stability of the delivery system. The partially amorphous nature of drug-loaded SMMs, as confirmed by X-ray diffraction patterns, further strengthened the matricization of AZT into the pectin-mucin matrix. In vitro drug release studies from the SMMs showed approximately 91% zidovudine release in simulated vaginal fluid (SVF) and 94% in phosphate buffered saline (PBS) in 24h. The mean dissolution time (MDT) of zidovudine from the SMMs was 5.974 h. The attainment of required dimensional structure and drug release profiles from SMMs highlights the potential of their inclusion into a secondary carrier system for extended and controlled intravaginal stay.

  6. Stimulation of Liver X Receptor Has Potent Anti-HIV Effects in a Humanized Mouse Model of HIV Infection.

    PubMed

    Ramezani, Ali; Dubrovsky, Larisa; Pushkarsky, Tatiana; Sviridov, Dmitri; Karandish, Sara; Raj, Dominic S; Fitzgerald, Michael L; Bukrinsky, Michael

    2015-09-01

    Previous studies demonstrated that liver X receptor (LXR) agonists inhibit human immunodeficiency virus (HIV) replication by upregulating cholesterol transporter ATP-binding cassette A1 (ABCA1), suppressing HIV production, and reducing infectivity of produced virions. In this study, we extended these observations by analyzing the effect of the LXR agonist T0901317 [N-[4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenyl]-N-(2,2,2-trifluoroethyl)benzenesulfonamide] on the ongoing HIV infection and investigating the possibility of using LXR agonist for pre-exposure prophylaxis of HIV infection in a humanized mouse model. Pre-exposure of monocyte-derived macrophages to T0901317 reduced susceptibility of these cells to HIV infection in vitro. This protective effect lasted for up to 4 days after treatment termination and correlated with upregulated expression of ABCA1, reduced abundance of lipid rafts, and reduced fusion of the cells with HIV. Pre-exposure of peripheral blood leukocytes to T0901317 provided only a short-term protection against HIV infection. Treatment of HIV-exposed humanized mice with LXR agonist starting 2 weeks postinfection substantially reduced viral load. When eight humanized mice were pretreated with LXR agonist prior to HIV infection, five animals were protected from infection, two had viral load at the limit of detection, and one had viral load significantly reduced relative to mock-treated controls. T0901317 pretreatment also reduced HIV-induced dyslipidemia in infected mice. In conclusion, these results reveal a novel link between LXR stimulation and cell resistance to HIV infection and suggest that LXR agonists may be good candidates for development as anti-HIV agents, in particular for pre-exposure prophylaxis of HIV infection.

  7. The effects of inhomogeneous boundary dilution on the coating flow of an anti-HIV microbicide vehicle

    NASA Astrophysics Data System (ADS)

    Tasoglu, Savas; Peters, Jennifer J.; Park, Su Chan; Verguet, Stéphane; Katz, David F.; Szeri, Andrew J.

    2011-09-01

    A recent study in South Africa has confirmed, for the first time, that a vaginal gel formulation of the antiretroviral drug Tenofovir, when topically applied, significantly inhibits sexual HIV transmission to women [Karim et al., Science 329, 1168 (2010)]. However, the gel for this drug and anti-HIV microbicide gels in general have not been designed using an understanding of how gel spreading and retention in the vagina govern successful drug delivery. Elastohydrodynamic lubrication theory can be applied to model spreading of microbicide gels [Szeri et al., Phys. Fluids 20, 083101 (2008)]. This should incorporate the full rheological behavior of a gel, including how rheological properties change due to contact with, and dilution by, ambient vaginal fluids. Here, we extend our initial analysis, incorporating the effects of gel dilution due to contact with vaginal fluid produced at the gel-tissue interface. Our original model is supplemented with a convective-diffusive transport equation to characterize water transport into the gel and, thus, local gel dilution. The problem is solved using a multi-step scheme in a moving domain. The association between local dilution of gel and rheological properties is obtained experimentally, delineating the way constitutive parameters of a shear-thinning gel are modified by dilution. Results show that dilution accelerates the coating flow by creating a slippery region near the vaginal wall akin to a dilution boundary layer, especially if the boundary flux exceeds a certain value. On the other hand, if the diffusion coefficient of boundary fluid is increased, the slippery region diminishes in extent and the overall rate of gel spreading decreases.

  8. Elucidation of roles for vitamin B12 in regulation of folate, ubiquinone, and methionine metabolism

    PubMed Central

    Romine, Margaret F.; Rodionov, Dmitry A.; Maezato, Yukari; Anderson, Lindsey N.; Nandhikonda, Premchendar; Rodionova, Irina A.; Carre, Alexandre; Li, Xiaoqing; Xu, Chengdong; Clauss, Therese R. W.; Metz, Thomas O.; Wright, Aaron T.

    2017-01-01

    Only a small fraction of vitamin B12-requiring organisms are able to synthesize B12 de novo, making it a common commodity in microbial communities. Initially recognized as an enzyme cofactor of a few enzymes, recent studies have revealed additional B12-binding enzymes and regulatory roles for B12. Here we report the development and use of a B12-based chemical probe to identify B12-binding proteins in a nonphototrophic B12-producing bacterium. Two unexpected discoveries resulted from this study. First, we identified a light-sensing B12-binding transcriptional regulator and demonstrated that it controls folate and ubiquinone biosynthesis. Second, our probe captured proteins involved in folate, methionine, and ubiquinone metabolism, suggesting that it may play a role as an allosteric effector of these processes. These metabolic processes produce precursors for synthesis of DNA, RNA, and protein. Thereby, B12 likely modulates growth, and by limiting its availability to auxotrophs, B12-producing organisms may facilitate coordination of community metabolism. PMID:28137868

  9. Vitamin B12 transport from food to the body's cells--a sophisticated, multistep pathway.

    PubMed

    Nielsen, Marianne J; Rasmussen, Mie R; Andersen, Christian B F; Nexø, Ebba; Moestrup, Søren K

    2012-05-01

    Vitamin B(12) (B(12); also known as cobalamin) is a cofactor in many metabolic processes; deficiency of this vitamin is associated with megaloblastic anaemia and various neurological disorders. In contrast to many prokaryotes, humans and other mammals are unable to synthesize B(12). Instead, a sophisticated pathway for specific uptake and transport of this molecule has evolved. Failure in the gastrointestinal part of this pathway is the most common cause of nondietary-induced B(12) deficiency disease. However, although less frequent, defects in cellular processing and further downstream steps in the transport pathway are also known culprits of functional B(12) deficiency. Biochemical and genetic approaches have identified novel proteins in the B(12) transport pathway--now known to involve more than 15 gene products--delineating a coherent pathway for B(12) trafficking from food to the body's cells. Some of these gene products are specifically dedicated to B(12) transport, whereas others embrace additional roles, which explains the heterogeneity in the clinical picture of the many genetic disorders causing B(12) deficiency. This Review describes basic and clinical features of this multistep pathway with emphasis on gastrointestinal transport of B(12) and its importance in clinical medicine.

  10. Elucidation of roles for vitamin B12 in regulation of folate, ubiquinone, and methionine metabolism.

    PubMed

    Romine, Margaret F; Rodionov, Dmitry A; Maezato, Yukari; Anderson, Lindsey N; Nandhikonda, Premchendar; Rodionova, Irina A; Carre, Alexandre; Li, Xiaoqing; Xu, Chengdong; Clauss, Therese R W; Kim, Young-Mo; Metz, Thomas O; Wright, Aaron T

    2017-02-14

    Only a small fraction of vitamin B12-requiring organisms are able to synthesize B12 de novo, making it a common commodity in microbial communities. Initially recognized as an enzyme cofactor of a few enzymes, recent studies have revealed additional B12-binding enzymes and regulatory roles for B12 Here we report the development and use of a B12-based chemical probe to identify B12-binding proteins in a nonphototrophic B12-producing bacterium. Two unexpected discoveries resulted from this study. First, we identified a light-sensing B12-binding transcriptional regulator and demonstrated that it controls folate and ubiquinone biosynthesis. Second, our probe captured proteins involved in folate, methionine, and ubiquinone metabolism, suggesting that it may play a role as an allosteric effector of these processes. These metabolic processes produce precursors for synthesis of DNA, RNA, and protein. Thereby, B12 likely modulates growth, and by limiting its availability to auxotrophs, B12-producing organisms may facilitate coordination of community metabolism.

  11. Metabolic vitamin B12 deficiency: a missed opportunity to prevent dementia and stroke.

    PubMed

    Spence, J David

    2016-02-01

    The purpose of this narrative review is to highlight insights into the importance and frequency of metabolic vitamin B12 (B12) deficiency, reasons why it is commonly missed, and reasons for the widespread but mistaken belief that treatment of B12 deficiency does not prevent stroke or improve cognitive function. Metabolic B12 deficiency is common, being present in 10%-40% of the population; is frequently missed; is easily treated; and contributes importantly to cognitive decline and stroke in older people. Measuring serum B12 alone is not sufficient for diagnosis; it is necessary to measure holotranscobalamin or functional markers of B12 adequacy such as methylmalonic acid or plasma total homocysteine. B-vitamin therapy with cyanocobalamin reduces the risk of stroke in patients with normal renal function but is harmful (perhaps because of thiocyanate accumulation from cyanide in cyanocobalamin) in patients with renal impairment. Methylcobalamin may be preferable in renal impairment. B12 therapy slowed gray matter atrophy and cognitive decline in the Homocysteine and B Vitamins in Cognitive Impairment Trial. Undiagnosed metabolic B12 deficiency may be an important missed opportunity for prevention of dementia and stroke; in patients with metabolic B12 deficiency, it would be prudent to offer inexpensive and nontoxic supplements of oral B12, preferably methylcobalamin or hydroxycobalamin. Future research is needed to distinguish the effects of thiocyanate from cyanocobalamin on hydrogen sulfide, and effects of treatment with methylcobalamin on cognitive function and stroke, particularly in patients with renal failure.

  12. Vitamin B12-loaded solid lipid nanoparticles as a drug carrier in cancer therapy.

    PubMed

    Genç, Lütfi; Kutlu, H Mehtap; Güney, Gamze

    2015-05-01

    Nanostructure-mediated drug delivery, a key technology for the realization of nanomedicine, has the potential to improve drug bioavailability, ameliorate release deviation of drug molecules and enable precision drug targeting. Due to their multifunctional properties, solid lipid nanoparticles (SLNs) have received great attention of scientists to find a solution to cancer. Vitamin supplements may contribute to a reduction in the risk of cancer. Vitamin B12 has several characteristics that make it an attractive entity for cancer treatment and possible therapeutic applications. The aim of this study was to produce B12-loaded SLNs (B12-SLNs) and determine the cytotoxic effects of B12-SLNs on H-Ras 5RP7 and NIH/3T3 control cell line. Results obtained by MTT assay, transmission electron and confocal microscopy showed that B12-loaded SLNs are more effective than free vitamin B12 on cancer cells. In addition, characterization studies indicate that while the average diameter of the B12 was about 650 nm, B12-SLNs were about 200 nm and the drug release efficiency of vit. B12 by means of SLNs increased up to 3 h. These observations point to the fact that B12-SLNs could be used as carrier systems due to the therapeutic effects on cancer.

  13. Vitamin B-12-deficiency affects immunoglobulin production and cytokine levels in mice.

    PubMed

    Funada, U; Wada, M; Kawata, T; Mori, K; Tamai, H; Isshiki, T; Onoda, J; Tanaka, N; Tadokoro, T; Maekawa, A

    2001-01-01

    To clarify the role of B-12 in the immunological function, serum C3, IgM, IgG, IgE contents, splenocytes expression of CD4, CD8, and CD4 positive intracellular IFN-gamma and IL-4 were examined in B-12-deficient mice, and the effect of the administration of CH3-B-12 was also studied. Serum C3, IgM and IgG contents were lower in B-12-deficient mice than in the control mice. On the other hand, serum IgE content was significantly higher in B-12-deficient mice, and the value in CH3-B-12 administered mice, administered CH3-B-12 to B-12-deficient mice for 48 h before the end of feeding period, showed a tendency to recovery. CD4+CD8- cells and CD4+CD8-/CD4-CD8+ ratio in splenocytes were significantly higher in B-12-deficient mice than in control mice. CD4+IFN-gamma+ cells was significantly lower in B-12-deficient mice than in control mice, and CD4+IL-4+ was significantly higher in B-12-deficient mice than in control mice. These results suggest that B-12-deficiency causes CD4+CD8-T cells shift from the T helper type 1 to the T helper type 2, which participate in the IgE production and elevates CD4+CD8-/CD4-CD8+ ratio. Thus, B-12 plays a role in maintaining the immune function in mice.

  14. Antibacterial, anti-HIV-1 protease and cytotoxic activities of aqueous ethanolic extracts from Combretum adenogonium Steud. Ex A. Rich (Combretaceae)

    PubMed Central

    2012-01-01

    Background Records have shown that Combretum adenogonium Steud. Ex A. Rich (Combretaceae) is used in traditional medicine systems of several tribes in Tanzania. This study focused on the investigation of antibacterial activity, anti-HIV-1 protease activity, toxicity properties and classes of phytochemicals in extracts from C. adenogonium Steud. Ex A. Rich (Combretaceae) to evaluate potential of these extracts for development as herbal remedies. Methods Dried plant material were ground to fine powder and extracted using 80% aqueous ethanol to afford root, leaf and stem bark extracts. The extracts were assayed for anti-HIV-1 protease activities, antibacterial activities using microdilution methods and cytotoxicity using brine shrimps lethality assay. Screening for major phytochemical classes was carried out using standard chemical tests. Results All extracts exhibited antibacterial activity to at least one of the test bacteria with MIC-values ranging from 0.31-5.0 mg/ml. Two extracts, namely, root and stem bark exhibited anti-HIV-1 PR activity with IC50 values of 24.7 and 26.5 μg/ml, respectively. Stem bark and leaf extracts showed mild toxicity with LC50 values of 65.768 μg/ml and 76.965 μg/ml, respectively, whereas roots were relatively non-toxic (LC50 = 110.042 μg/ml). Phytochemical screening of the extracts indicated presence of flavonoids, terpenoids, alkaloids, tannins, glycosides and saponins. Conclusion These results provide promising baseline information for the potential development of C. adenogonium extracts in treatment of bacterial and HIV/AIDS-related opportunistic infections. PMID:23013240

  15. PolyICLC Exerts Pro- and Anti-HIV Effects on the DC-T Cell Milieu In Vitro and In Vivo.

    PubMed

    Aravantinou, Meropi; Frank, Ines; Hallor, Magnus; Singer, Rachel; Tharinger, Hugo; Kenney, Jessica; Gettie, Agegnehu; Grasperge, Brooke; Blanchard, James; Salazar, Andres; Piatak, Michael; Lifson, Jeffrey D; Robbiani, Melissa; Derby, Nina

    2016-01-01

    Myeloid dendritic cells (mDCs) contribute to both HIV pathogenesis and elicitation of antiviral immunity. Understanding how mDC responses to stimuli shape HIV infection outcomes will inform HIV prevention and treatment strategies. The long double-stranded RNA (dsRNA) viral mimic, polyinosinic polycytidylic acid (polyIC, PIC) potently stimulates DCs to focus Th1 responses, triggers direct antiviral activity in vitro, and boosts anti-HIV responses in vivo. Stabilized polyICLC (PICLC) is being developed for vaccine adjuvant applications in humans, making it critical to understand how mDC sensing of PICLC influences HIV infection. Using the monocyte-derived DC (moDC) model, we sought to describe how PICLC (vs. other dsRNAs) impacts HIV infection within DCs and DC-T cell mixtures. We extended this work to in vivo macaque rectal transmission studies by administering PICLC with or before rectal SIVmac239 (SIVwt) or SIVmac239ΔNef (SIVΔNef) challenge. Like PIC, PICLC activated DCs and T cells, increased expression of α4β7 and CD169, and induced type I IFN responses in vitro. The type of dsRNA and timing of dsRNA exposure differentially impacted in vitro DC-driven HIV infection. Rectal PICLC treatment similarly induced DC and T cell activation and pro- and anti-HIV factors locally and systemically. Importantly, this did not enhance SIV transmission in vivo. Instead, SIV acquisition was marginally reduced after a single high dose challenge. Interestingly, in the PICLC-treated, SIVΔNef-infected animals, SIVΔNef viremia was higher, in line with the importance of DC and T cell activation in SIVΔNef replication. In the right combination anti-HIV strategy, PICLC has the potential to limit HIV infection and boost HIV immunity.

  16. PolyICLC Exerts Pro- and Anti-HIV Effects on the DC-T Cell Milieu In Vitro and In Vivo

    PubMed Central

    Hallor, Magnus; Singer, Rachel; Tharinger, Hugo; Kenney, Jessica; Gettie, Agegnehu; Grasperge, Brooke; Blanchard, James; Salazar, Andres; Lifson, Jeffrey D.; Robbiani, Melissa; Derby, Nina

    2016-01-01

    Myeloid dendritic cells (mDCs) contribute to both HIV pathogenesis and elicitation of antiviral immunity. Understanding how mDC responses to stimuli shape HIV infection outcomes will inform HIV prevention and treatment strategies. The long double-stranded RNA (dsRNA) viral mimic, polyinosinic polycytidylic acid (polyIC, PIC) potently stimulates DCs to focus Th1 responses, triggers direct antiviral activity in vitro, and boosts anti-HIV responses in vivo. Stabilized polyICLC (PICLC) is being developed for vaccine adjuvant applications in humans, making it critical to understand how mDC sensing of PICLC influences HIV infection. Using the monocyte-derived DC (moDC) model, we sought to describe how PICLC (vs. other dsRNAs) impacts HIV infection within DCs and DC-T cell mixtures. We extended this work to in vivo macaque rectal transmission studies by administering PICLC with or before rectal SIVmac239 (SIVwt) or SIVmac239ΔNef (SIVΔNef) challenge. Like PIC, PICLC activated DCs and T cells, increased expression of α4β7 and CD169, and induced type I IFN responses in vitro. The type of dsRNA and timing of dsRNA exposure differentially impacted in vitro DC-driven HIV infection. Rectal PICLC treatment similarly induced DC and T cell activation and pro- and anti-HIV factors locally and systemically. Importantly, this did not enhance SIV transmission in vivo. Instead, SIV acquisition was marginally reduced after a single high dose challenge. Interestingly, in the PICLC-treated, SIVΔNef-infected animals, SIVΔNef viremia was higher, in line with the importance of DC and T cell activation in SIVΔNef replication. In the right combination anti-HIV strategy, PICLC has the potential to limit HIV infection and boost HIV immunity. PMID:27603520

  17. Acquired thermotolerance and heat shock in the extremely thermophilic archaebacterium Sulfolobus sp. strain B12.

    PubMed

    Trent, J D; Osipiuk, J; Pinkau, T

    1990-03-01

    The extreme thermophile Sulfolobus sp. strain B12 exhibits an acquired thermotolerance response. Thus, survival of cells from a 70 degrees C culture at the lethal temperature of 92 degrees C was enhanced by as much as 6 orders of magnitude over a 2-h period if the culture was preheated to 88 degrees C for 60 min or longer before being exposed to the lethal temperature. In eubacteria and eucaryotes, acquired thermotolerance correlates with the induced synthesis of a dozen or so proteins known as heat shock proteins. In this Sulfolobus species, it correlates with the preferential synthesis of primarily one major protein (55 kilodaltons) and, to a much lesser extent, two minor proteins (28 and 35 kilodaltons). Since the synthesis of all other proteins was radically reduced and these proteins were apparently not degraded or exported, their relative abundance within the cell increased during the time the cells were becoming thermotolerant. They could not yet be related to known heat shock proteins. In immunoassays, they were not cross-reactive with antibodies against heat shock proteins from Escherichia coli (DnaK and GroE), which are highly conserved between eubacteria and eucaryotes. However, it appears that if acquired thermotolerance depends on the synthesis of protective proteins, then in this extremely thermophilic archaebacterium it depends primarily on one protein.

  18. Acquired thermotolerance and heat shock in the extremely thermophilic archaebacterium Sulfolobus sp. strain B12

    SciTech Connect

    Trent, J.D.; Osipiuk, J.; Pinkau, T. )

    1990-03-01

    The extreme thermophile Sulfolobus sp. strain B12 exhibits an acquired thermotolerance response. Thus, survival of cells from a 70{degrees}C culture at the lethal temperature of 92{degrees}C was enhanced by as much as 6 orders of magnitude over a 2-h period if the culture was preheated to 88{degrees}C for 60 min or longer before being exposed to the lethal temperature. In eubacteria and eucaryotes, acquired thermotolerance correlates with the induced synthesis of a dozen or so proteins known as heat shock proteins. In this Sulfolobus species, it correlates with the preferential synthesis of primarily one major protein (55 kilodaltons) and, to a much lesser extent, two minor proteins (28 and 35 kilodaltons). Since the synthesis of all other proteins was radically reduced and these proteins were apparently not degraded or exported, their relative abundance within the cell increased during the time the cells were becoming thermotolerant. They could not yet be related to known heat shock proteins. In immunoassays, they were not cross-reactive with antibodies against heat shock proteins from Escherichia coli (DnaK and GroE), which are highly conserved between eubacteria and eucaryotes. However, it appears that if acquired thermotolerance depends on the synthesis of protective proteins, then in this extremely thermophilic archaebacterium it depends primarily on one protein.

  19. Bitter gourd (Momordica charantia) is a cornucopia of health: a review of its credited antidiabetic, anti-HIV, and antitumor properties.

    PubMed

    Fang, E F; Ng, T B

    2011-07-01

    Bitter gourd (Momordica charantia, BG) is both a nutritious and healthy food with a distinctive bitter flavor, and it is also widely exploited in folklore medicine. This review focuses on the efficacies and molecular mechanisms of BG-induced anti-diabetic, anti-HIV, and antitumor activities contributed by over twenty active components. The intent of this review is to provide comprehensive and valuable information for medicinal researchers, drug investigators, clinicians, and even patients with an interest in BG. In conclusion, BG is a cornucopia of health and it deserves in-depth investigations for clinical application in the future.

  20. Inhibition of the integrase of human immunodeficiency virus (HIV) type 1 by anti-HIV plant proteins MAP30 and GAP31.

    PubMed Central

    Lee-Huang, S; Huang, P L; Huang, P L; Bourinbaiar, A S; Chen, H C; Kung, H F

    1995-01-01

    MAP30 (Momordica anti-HIV protein of 30 kDa) and GAP31 (Gelonium anti-HIV protein of 31 kDa) are anti-HIV plant proteins that we have identified, purified, and cloned from the medicinal plants Momordica charantia and Gelonium multiflorum. These antiviral agents are capable of inhibiting infection of HIV type 1 (HIV-1) in T lymphocytes and monocytes as well as replication of the virus in already-infected cells. They are not toxic to normal uninfected cells because they are unable to enter healthy cells. MAP30 and GAP31 also possess an N-glycosidase activity on 28S ribosomal RNA and a topological activity on plasmid and viral DNAs including HIV-1 long terminal repeats (LTRs). LTRs are essential sites for integration of viral DNA into the host genome by viral integrase. We therefore investigated the effect of MAP30 and GAP31 on HIV-1 integrase. We report that both of these antiviral agents exhibit dose-dependent inhibition of HIV-1 integrase. Inhibition was observed in all of the three specific reactions catalyzed by the integrase, namely, 3' processing (specific cleavage of the dinucleotide GT from the viral substrate), strand transfer (integration), and "disintegration" (the reversal of strand transfer). Inhibition was studied by using oligonucleotide substrates with sequences corresponding to the U3 and U5 regions of HIV LTR. In the presence of 20 ng of viral substrate, 50 ng of target substrate, and 4 microM integrase, total inhibition was achieved at equimolar concentrations of the integrase and the antiviral proteins, with EC50 values of about 1 microM. Integration of viral DNA into the host chromosome is a vital step in the replicative cycle of retroviruses, including the AIDS virus. The inhibition of HIV-1 integrase by MAP30 and GAP31 suggests that impediment of viral DNA integration may play a key role in the anti-HIV activity of these plant proteins. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:7568024

  1. Synthesis and anti-HIV activity of lupane and olean-18-ene derivatives. Absolute configuration of 19,20-epoxylupanes by VCD.

    PubMed

    Gutiérrez-Nicolás, Fátima; Gordillo-Román, Bárbara; Oberti, Juan C; Estévez-Braun, Ana; Ravelo, Angel G; Joseph-Nathan, Pedro

    2012-04-27

    Lupane triterpenoids 2 and 5-12 and oleanene derivatives 13 and 14 were prepared from lupeol (1), betulin (3), and germanicol (4). They were tested for anti-HIV activity, and some structure-activity relationships were outlined. The 20-(S) absolute configuration of epoxylupenone (8) was assessed by comparison of the observed and DFT-calculated vibrational circular dichroism spectra. The CompareVOA algorithm was employed to support the C-20 configuration assignment. The 20,29 double bond in lupenone (2) and 3-epilupeol (15) was stereoselectively epoxidized to produce 20-(S)-8 and 20-(S)-16, respectively, an assignment in agreement with their X-ray diffraction structures.

  2. Experimental vitamin B12 deficiency in a human subject: a longitudinal investigation of the performance of the holotranscobalamin (HoloTC, Active-B12) immunoassay.

    PubMed

    Golding, Paul Henry

    2016-01-01

    Based on Victor Herbert's model for sequential stages in the development of vitamin B12 deficiency, the holotranscobalamin (HoloTC) immunoassay has controversially been promoted as a more specific and sensitive replacement for the total vitamin B12 test, for the diagnosis of deficiency. There have been no longitudinal studies, by means of experimental cobalamin deficiency, because ethical considerations prevent such risky studies on patients or healthy human volunteers. The objective was to provide a detailed record of the response of HoloTC, compared to total vitamin B12 and metabolites, to the development of experimental vitamin B12 deficiency in an initially replete human subject. This 54 year old male, with a vitamin B12 deficiency possibly caused by a defect in the intracellular cobalamin metabolism, ensured an initially replete condition by means of oral doses of cyanocobalamin supplements at 1000 μg/day for 12 weeks. The subject then depleted himself of vitamin B12, by withholding treatment and using a low-cobalamin diet, until significant metabolic disturbances were observed. The responses of serum total vitamin B12 and HoloTC and the two metabolites, plasma methylmalonic acid and homocysteine, were monitored by weekly blood tests. HoloTC was not significantly more sensitive than either total serum vitamin B12 or total homocysteine, and was much less sensitive than methylmalonic acid. HoloTC decreased from an initial concentration of >128 pmol/L to a minimum of 33 pmol/L on day 742, the only day on which it fell below the lower limit of the reference interval. Total vitamin B12 decreased from an initial concentration of 606 pmol/L to a minimum of 171 pmol/L on day 728. Total homocysteine increased from an initial concentration of 8.4 μmol/L to a maximum of 14.2 μmol/L on day 609. Methylmalonic acid unexpectedly contained four distinct peaks; initially at 0.17 μmol/L, it first exceeded the upper limit of the reference interval on day 386

  3. A Cinnamon-Derived Procyanidin Compound Displays Anti-HIV-1 Activity by Blocking Heparan Sulfate- and Co-Receptor- Binding Sites on gp120 and Reverses T Cell Exhaustion via Impeding Tim-3 and PD-1 Upregulation

    PubMed Central

    Connell, Bridgette Janine; Chang, Sui-Yuan; Prakash, Ekambaranellore; Yousfi, Rahima; Mohan, Viswaraman; Posch, Wilfried; Wilflingseder, Doris; Moog, Christiane; Kodama, Eiichi N.; Clayette, Pascal; Lortat-Jacob, Hugues

    2016-01-01

    Amongst the many strategies aiming at inhibiting HIV-1 infection, blocking viral entry has been recently recognized as a very promising approach. Using diverse in vitro models and a broad range of HIV-1 primary patient isolates, we report here that IND02, a type A procyanidin polyphenol extracted from cinnamon, that features trimeric and pentameric forms displays an anti-HIV-1 activity against CXCR4 and CCR5 viruses with 1–7 μM ED50 for the trimer. Competition experiments, using a surface plasmon resonance-based binding assay, revealed that IND02 inhibited envelope binding to CD4 and heparan sulphate (HS) as well as to an antibody (mAb 17b) directed against the gp120 co-receptor binding site with an IC50 in the low μM range. IND02 has thus the remarkable property of simultaneously blocking gp120 binding to its major host cell surface counterparts. Additionally, the IND02-trimer impeded up-regulation of the inhibitory receptors Tim-3 and PD-1 on CD4+ and CD8+ cells, thereby demonstrating its beneficial effect by limiting T cell exhaustion. Among naturally derived products significantly inhibiting HIV-1, the IND02-trimer is the first component demonstrating an entry inhibition property through binding to the viral envelope glycoprotein. These data suggest that cinnamon, a widely consumed spice, could represent a novel and promising candidate for a cost-effective, natural entry inhibitor for HIV-1 which can also down-modulate T cell exhaustion markers Tim-3 and PD-1. PMID:27788205

  4. LDEF (Prelaunch), AO201 : Interplanetary Dust Experiment, Tray B12

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), AO201 : Interplanetary Dust Experiment, Tray B12 The prelaunch photograph shows the six (6) inch deep Interplanetary Dust Experiment (IDE) master control tray. The tray has three (3) mounting/cover plates elevated on fiberglass stand-offs to provide clearance and protection for hardware and electronics located underneath. The stand-offs also raise the plates to a level that minimizes shading of detectors by the tray sidewalls. The mounting plate located at the left hand end of the tray is populated with eighty (80) metaloxide-silicon (MOS) capacitor-type impact sensors and one (1) solar sensor that is located approximately in the center of the mounting plate. The IDE sensors are two (2) inch diameter MOS capacitor structures approximately 250 um thick. The detectors are formed by growing either 0.4um or 1.0um thick silicon oxide, SiO2, layer on the 250um thick, B-doped polished silicon wafer. The top metal contact, the visible surface, was formed by vapor deposition of 1000A of aluminum on the SiO2 surface. Aluminum was also vapor deposited on the backside to form the contact with the silicon substrate. Gold wires are bonded to the front and back aluminum layers for use in connecting the detectors to the circuits. The complete wafers, IDE detectors, are mounted on chromic anodized aluminum frames by bonding the detector backside to the aluminum frame with a space qualified RTV silicon adhesive, de-volatized RTV-511. The difference in colors of the detectors is caused by reflections in the metallized surfaces. A reflection of one of the technicians is visible in the three (3) rows of detector on the left hand side of the mounting plate. The solar sensor, located at the mounting plate center, consist of four (4) silicon solar cells connected in series and associated circuity bonded to an aluminum baseplate. The solar sensor registered each orbital sunrise independant of LDEF orientation at the time of sunrise. When IDE solar sensor data from the six

  5. Vitamin B12 deficiency in the elderly: is it worth screening?

    PubMed

    Wong, C W

    2015-04-01

    Vitamin B12 deficiency is common among the elderly. Elderly people are particularly at risk of vitamin B12 deficiency because of the high prevalence of atrophic gastritis-associated food-cobalamin (vitamin B12) malabsorption, and the increasing prevalence of pernicious anaemia with advancing age. The deficiency most often goes unrecognised because the clinical manifestations are highly variable, often subtle and non-specific, but if left undiagnosed the consequences can be serious. Diagnosis of vitamin B12 deficiency, however, is not straightforward as laboratory tests have certain limitations. Setting a cut-off level to define serum vitamin B12 deficiency is difficult; though homocysteine and methylmalonic acid are more sensitive for vitamin B12 deficiency, it may give false result in some conditions and the reference intervals are not standardised. At present, there is no consensus or guideline for diagnosis of this deficiency. It is most often based on the clinical symptoms together with laboratory assessment (low serum vitamin B12 level and elevated serum homocysteine or methylmalonic acid level) and the response to treatment to make definitive diagnosis. Treatment and replacement with oral vitamin B12 can be as effective as parenteral administration even in patients with pernicious anaemia. The suggested oral vitamin B12 dose is 1 mg daily for a month, and then maintenance dose of 125 to 250 µg for patients with dietary insufficiency and 1 mg daily for those with pernicious anaemia. Vitamin B12 replacement is safe and without side-effects, but prompt treatment is required to reverse the damage before it becomes extensive or irreversible. At present, there is no recommendation for mass screening for vitamin B12 in the elderly. Nevertheless, the higher prevalence with age, increasing risk of vitamin B12 deficiency in the elderly, symptoms being difficult to recognise, and availability of safe treatment options make screening a favourable option. However, the

  6. Vitamin B12 status of elderly persons from urban low-income households.

    PubMed

    Bailey, L B; Wagner, P A; Christakis, G J; Araujo, P E; Appledorf, H; Davis, C G; Dorsey, E; Dinning, J S

    1980-06-01

    Vitamin B12 status was evaluated in 111 noninstitutional elderly persons (age range, 60-87 years) living in an urban poverty area. The sample was predominantly black (90 subjects); the rest were Spanish Americans. Serum vitamin B12 levels were all normal (greater than 200 pg/ml) and ranged from 226 to 1200 pg/ml (mean +/- SD = 700 +/- 191 pg/ml). The findings indicate that vitamin B12 deficiency was not a problem in this elderly population.

  7. Influence of Co and B12 on the growth and nitrogen fixation of Trichodesmium

    PubMed Central

    Rodriguez, Irene B.; Ho, Tung-Yuan

    2015-01-01

    We investigated the influence of varying cobalt (Co) and B12 concentrations to growth and nitrogen fixation of Trichodesmium, a major diazotroph in the tropical and subtropical oligotrophic ocean. Here we show that sufficient inorganic Co, 20 pmol L-1, sustains the growth of Trichodesmium either with or without an additional B12 supply. We also found that in these culture conditions, nitrogen levels fixed by Trichodesmium were higher in treatments with insufficient B12 than in treatments with higher B12 availability. Under limited inorganic Co availability, ranging from 0.2 to 2 pmol L-1, Trichodesmium growth was significantly compromised in cultures without B12. In these low Co concentrations, addition of 400 pmol L-1 of B12 supported phytoplankton growth indicating that B12 supply augmented for the low Co concentrations. Our study demonstrates that Trichodesmium has an absolute Co requirement, which is not replaceable with Zn, and that B12 supply alleviates stress in cases where Co is limiting. These results show that the interlocking availabilities of Co and B12 may influence the growth and nitrogen fixation of Trichodesmium in the ocean. PMID:26150813

  8. Measurements of vitamin B12 in human blood serum using resonance Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Tsiminis, G.; Schartner, E. P.; Brooks, J. L.; Hutchinson, M. R.

    2016-12-01

    Vitamin B12 (cobalamin and its derivatives) deficiency has been identified as a potential modifiable risk factor for dementia and Alzheimer's disease. Chronic deficiency of vitamin B12 has been significantly associated with an increased risk of cognitive decline. An effective and efficient method for measuring vitamin B12 concentration in human blood would enable ongoing tracking and assessment of this potential modifiable risk factor. In this work we present an optical sensor based on resonance Raman spectroscopy for rapid measurements of vitamin B12 in human blood serum. The measurement takes less than a minute and requires minimum preparation (centrifuging) of the collected blood samples.

  9. Navigating the B12 Road: Assimilation, Delivery, and Disorders of Cobalamin*

    PubMed Central

    Gherasim, Carmen; Lofgren, Michael; Banerjee, Ruma

    2013-01-01

    The reactivity of the cobalt-carbon bond in cobalamins is the key to their chemical versatility, supporting both methyl transfer and isomerization reactions. During evolution of higher eukaryotes that utilize vitamin B12, the high reactivity of the cofactor coupled with its low abundance pressured development of an efficient system for uptake, assimilation, and delivery of the cofactor to client B12-dependent enzymes. Although most proteins suspected to be involved in B12 trafficking were discovered by 2009, the recent identification of a new protein reveals that the quest for elucidating the intracellular B12 highway is still far from complete. Herein, we review the biochemistry of cobalamin trafficking. PMID:23539619

  10. Peptide B12: emerging trends at the interface of inorganic chemistry, chemical biology and medicine.

    PubMed

    Zelder, Felix; Zhou, Kai; Sonnay, Marjorie

    2013-01-28

    The sophisticated and efficient delivery of vitamin B(12) ("B(12)") into cells offers promise for B(12)-bioconjugates in medicinal diagnosis and therapy. It is therefore surprising that rather little attention is presently paid to an alternative strategy in drug design: the development of structurally perfect, but catalytically inactive semi-artificial B(12) surrogates. Vitamin B(12) cofactors catalyse important biological transformations and are indispensible for humans and most other forms of life. This strong metabolic dependency exhibits enormous medicinal opportunities. Inhibitors of B(12) dependent enzymes are potential suppressors of fast proliferating cancer cells. This perspective article focuses on the design and study of backbone modified B(12) derivatives, particularly on peptide B(12) derivatives. Peptide B(12) is a recently introduced class of biomimetic cobalamins bearing an artificial peptide backbone with adjustable coordination and redox-properties. Pioneering biological studies demonstrated reduced catalytic activity, combined with inhibitory potential that is encouraging for future efforts in turning natural cofactors into new anti-proliferative agents.

  11. Signature Biochemical Properties of Broadly Cross-Reactive HIV-1 Neutralizing Antibodies in Human Plasma

    PubMed Central

    Sajadi, Mohammad M.; Lewis, George K.; Seaman, Michael S.; Guan, Yongjun; Redfield, Robert R.

    2012-01-01

    The common properties of broadly cross-reactive HIV-1 neutralization antibodies found in certain HIV-1-infected individuals holds significant value for understanding natural and vaccine-mediated anti-HIV immunity. Recent efforts have addressed this question by deriving neutralizing monoclonal anti-envelope antibodies from memory B cell pools of selected subjects. However, it has been more difficult to identify whether broadly neutralizing antibodies circulating in plasma possess shared characteristics among individuals. To address this question, we used affinity chromatography and isoelectric focusing to fractionate plasma immunoglobulin from 10 HIV-1-infected subjects (5 subjects with broad HIV-1 neutralizing activity and 5 controls). We find that plasma neutralizing activity typically partitions into at least two subsets of antibodies. Antibodies with restricted neutralization breadth have relatively neutral isoelectric points and preferentially bind to envelope monomers and trimers versus core antigens from which variable loops and other domains have been deleted. In comparison, broadly neutralizing antibodies account for a minor fraction of the total anti-envelope response. They are consistently distinguished by more basic isoelectric points and specificity for epitopes shared by monomeric gp120, gp120 core, or CD4-induced structures. Such biochemical properties might be exploited to reliably predict or produce broad anti-HIV immunity. PMID:22379105

  12. Signature biochemical properties of broadly cross-reactive HIV-1 neutralizing antibodies in human plasma.

    PubMed

    Sajadi, Mohammad M; Lewis, George K; Seaman, Michael S; Guan, Yongjun; Redfield, Robert R; DeVico, Anthony L

    2012-05-01

    The common properties of broadly cross-reactive HIV-1 neutralization antibodies found in certain HIV-1-infected individuals holds significant value for understanding natural and vaccine-mediated anti-HIV immunity. Recent efforts have addressed this question by deriving neutralizing monoclonal anti-envelope antibodies from memory B cell pools of selected subjects. However, it has been more difficult to identify whether broadly neutralizing antibodies circulating in plasma possess shared characteristics among individuals. To address this question, we used affinity chromatography and isoelectric focusing to fractionate plasma immunoglobulin from 10 HIV-1-infected subjects (5 subjects with broad HIV-1 neutralizing activity and 5 controls). We find that plasma neutralizing activity typically partitions into at least two subsets of antibodies. Antibodies with restricted neutralization breadth have relatively neutral isoelectric points and preferentially bind to envelope monomers and trimers versus core antigens from which variable loops and other domains have been deleted. In comparison, broadly neutralizing antibodies account for a minor fraction of the total anti-envelope response. They are consistently distinguished by more basic isoelectric points and specificity for epitopes shared by monomeric gp120, gp120 core, or CD4-induced structures. Such biochemical properties might be exploited to reliably predict or produce broad anti-HIV immunity.

  13. Synthesis of new 2′-deoxy-2′-fluoro-4′-azido nucleoside analogues as potent anti-HIV agents

    PubMed Central

    Wang, Qiang; Hu, Weidong; Wang, Shuyang; Pan, Zhenliang; Tao, Le; Guo, Xiaohe; Qian, Keduo; Chen, Chin-Ho; Lee, Kuo-Hsiung; Chang, Junbiao

    2011-01-01

    We prepared 1-(4′-azido-2′-deoxy-2′-fluoro-β -D-arabinofuranosyl)cytosine (10) and its hydrochloride salt (11) as potential antiviral agents based on the favorable antiviral profiles of 4′-substituted nucleosides. Compounds 10 and 11 were synthesized from 1,3,5-O-tribenzoyl-2-deoxy-2-fluoro-D-arabinofuranoside in multiple steps, and their structures were unequivocally established by IR, 1H NMR, 13C NMR, and 19F NMR spectroscopy, HRMS, and X-ray crystallography. Compounds 10 and 11 exhibited potent anti-HIV-1 activity (EC50: 0.3 and 0.13 nM, respectively) without significant cytotoxicity in concentrations up to 100 μM. Compound 11 exhibited extremely potent anti-HIV activity against NL4-3 (wild-type), NL4-3 (K101E), and RTMDR viral strains, with EC50 values of 0.086, 0.15, and 0.11 nM, respectively. Due to the high potency of 11, it was also screened against an NIH Reagent Program NRTI-resistant virus panel containing eleven mutated viral strains and for cytotoxicity against six different human cell lines. The results of this screening indicated that 11 is a novel NRTI that could be developed as an anti-AIDS clinical trial candidate to overcome drug-resistance issues. PMID:21745701

  14. D77, one benzoic acid derivative, functions as a novel anti-HIV-1 inhibitor targeting the interaction between integrase and cellular LEDGF/p75

    SciTech Connect

    Du Li; Zhao Yaxue; Chen, Jing; Yang Liumeng; Zheng Yongtang; Tang Yun Shen Xu Jiang Hualiang

    2008-10-10

    Integration of viral-DNA into host chromosome mediated by the viral protein HIV-1 integrase (IN) is an essential step in the HIV-1 life cycle. In this process, Lens epithelium-derived growth factor (LEDGF/p75) is discovered to function as a cellular co-factor for integration. Since LEDGF/p75 plays an important role in HIV integration, disruption of the LEDGF/p75 interaction with IN has provided a special interest for anti-HIV agent discovery. In this work, we reported that a benzoic acid derivative, 4-[(5-bromo-4-{l_brace}[2,4-dioxo-3-(2-oxo-2-phenylethyl) -1,3-thiazolidin-5-ylidene]methyl{r_brace}-2-ethoxyphenoxy)methyl]benzoic acid (D77) could potently inhibit the IN-LEDGF/p75 interaction and affect the HIV-1 IN nuclear distribution thus exhibiting antiretroviral activity. Molecular docking with site-directed mutagenesis analysis and surface plasmon resonance (SPR) binding assays has clarified possible binding mode of D77 against HIV-1 integrase. As the firstly discovered small molecular compound targeting HIV-1 integrase interaction with LEDGF/p75, D77 might supply useful structural information for further anti-HIV agent discovery.

  15. Concise synthesis and anti-HIV activity of pyrimido[1,2-c][1,3]benzothiazin-6-imines and related tricyclic heterocycles.

    PubMed

    Mizuhara, Tsukasa; Oishi, Shinya; Ohno, Hiroaki; Shimura, Kazuya; Matsuoka, Masao; Fujii, Nobutaka

    2012-09-07

    3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182) is a virucidal heterocyclic compound active against various viruses, including HCV, HIV, and simian immunodeficiency virus. Using facile synthetic approaches that we developed for the synthesis of pyrimido[1,2-c][1,3]benzothiazin-6-imines and related tricyclic derivatives, the parallel structural optimizations of the central 1,3-thiazin-2-imine core, the benzene part, and the cyclic amidine part of PD 404182 were investigated. Replacement of the 6-6-6 pyrimido[1,2-c][1,3]benzothiazin-6-imine framework with 5-6-6 or 6-6-5 derivatives led to a significant loss of anti-HIV activity, and introduction of a hydrophobic group at the 9- or 10-positions improved the potency. In addition, we demonstrated that the PD 404182 derivative exerts anti-HIV effects at an early stage of viral infection.

  16. Medicinal attributes of Solanum xanthocarpum fruit consumed by several tribal communities as food: an in vitro antioxidant, anticancer and anti HIV perspective

    PubMed Central

    2014-01-01

    Background Solanum xanthocarpum (Solanaceae) has been used for treatment of many infectious and degenerative diseases in traditional medicine. Present study reports the medicinal efficacy of S. xanthocarpum fruit as antioxidant, anticancer and anti HIV agents. Methods Extracts were prepared using Soxhlet apparatus and partially characterized by thin layer chromatography (TLC). Total flavonoid content was determined spectrophotometrically. Reducing power, DPPH radical scavenging activity and lipid peroxidation inhibition assays were used for measurement of antioxidant potential. Cytotoxic (SRB assay) and anti-HIV RT inhibition (RT assay kit, Roche) activities were determined using ELISA. Results TLC revealed the diversity of phytoconstituents in various sequential extracts of S. xanthocarpum fruit. Total flavonoid contents in extracts ranged between 10.22–162.49 μg quercetin equivalent/mg. Spectroscopic scanning of water soluble phenolics showed maximum absorbance at 250 and 280 nm. Polar extracts displayed potent radical scavenging activity (>80%). Several sub-fractions (spots) of extracts separated on TLC plates also exhibited powerful radical scavenging activity. Considerable reducing power was observed in extracts. Hexane fraction provided 55% lipoprotection in rat kidney homogenate. Non-polar extracts exhibited appreciable cytotoxic activity (70-91%) against leukemia (THP-1) and lung cancer (HOP-62) cell lines. Lower inhibitory activity was observed in extracts against HIV Reverse Transcriptase enzyme. Conclusion The study demonstrated considerable antioxidant and anticancer activities in S. xanthocarpum fruit. PMID:24678980

  17. Zirconium phosphatidylcholine-based nanocapsules as an in vivo degradable drug delivery system of MAP30, a momordica anti-HIV protein.

    PubMed

    Caizhen, Guo; Yan, Gao; Ronron, Chang; Lirong, Yang; Panpan, Chu; Xuemei, Hu; Yuanbiao, Qiao; Qingshan, Li

    2015-04-10

    An essential in vivo drug delivery system of a momordica anti-HIV protein, MAP30, was developed through encapsulating in chemically synthesized matrices of zirconium egg- and soy-phosphatidylcholines, abbreviated to Zr/EPC and Zr/SPC, respectively. Matrices were characterized by transmission electron microscopy and powder X-ray diffractometry studies. Zr/EPC granule at an approximate diameter of 69.43±7.78 nm was a less efficient encapsulator than the granule of Zr/SPC. Interlayer spacing of the matrices encapsulating MAP30 increased from 8.8 and 9.7 Å to 7.4 and 7.9 nm, respectively. In vivo kinetics on degradation and protein release was performed by analyzing the serum sampling of intravenously injected SPF chickens. The first order and biphasic variations were obtained for in vivo kinetics using equilibrium dialysis. Antimicrobial and anti-HIV assays yielded greatly decreased MIC50 and EC50 values of nanoformulated MAP30. An acute toxicity of MAP30 encapsulated in Zr/EPC occurred at a single intravenous dose above 14.24 mg/kg bw in NIH/KM/ICR mice. The folding of MAP30 from Zr/EPC sustained in vivo chickens for more than 8 days in high performance liquid chromatography assays. These matrices could protect MAP30 efficiently with strong structure retention, lowered toxicity and prolonged in vivo life.

  18. Competitive chemiluminescent enzyme immunoassay for vitamin B12 analysis in human milk

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND Few accurate data exist on the concentration of vitamin B12 in human milk. Binding of the vitamin to haptocorrin (HC) can interfere with the assay if not removed by pretreatment, and very low values can occur in women with poor B12 status. This study evaluated two competitive enzyme bind...

  19. 17 CFR 270.8b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., printing and language. 270.8b-12 Section 270.8b-12 Commodity and Securities Exchanges SECURITIES AND... Requirements as to paper, printing and language. (a) Registration statements and reports shall be filed on good...) Registration statements and reports shall be in the English language. If any exhibit or other paper or...

  20. 17 CFR 240.12b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., printing and language. 240.12b-12 Section 240.12b-12 Commodity and Securities Exchanges SECURITIES AND... paper, printing and language. (a) Statements and reports shall be filed on good quality, unglazed white... at least 2 points. (d)(1) All Exchange Act filings and submissions must be in the English...

  1. 17 CFR 240.12b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., printing and language. 240.12b-12 Section 240.12b-12 Commodity and Securities Exchanges SECURITIES AND... paper, printing and language. (a) Statements and reports shall be filed on good quality, unglazed white... at least 2 points. (d)(1) All Exchange Act filings and submissions must be in the English...

  2. 17 CFR 270.8b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., printing and language. 270.8b-12 Section 270.8b-12 Commodity and Securities Exchanges SECURITIES AND... Requirements as to paper, printing and language. (a) Registration statements and reports shall be filed on good... and reports shall be in the English language. If any exhibit or other paper or document filed with...

  3. 17 CFR 240.12b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., printing and language. 240.12b-12 Section 240.12b-12 Commodity and Securities Exchanges SECURITIES AND... paper, printing and language. (a) Statements and reports shall be filed on good quality, unglazed white... at least 2 points. (d)(1) All Exchange Act filings and submissions must be in the English...

  4. 17 CFR 270.8b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., printing and language. 270.8b-12 Section 270.8b-12 Commodity and Securities Exchanges SECURITIES AND... Requirements as to paper, printing and language. (a) Registration statements and reports shall be filed on good...) Registration statements and reports shall be in the English language. If any exhibit or other paper or...

  5. 17 CFR 270.8b-12 - Requirements as to paper, printing and language.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., printing and language. 270.8b-12 Section 270.8b-12 Commodity and Securities Exchanges SECURITIES AND... Requirements as to paper, printing and language. (a) Registration statements and reports shall be filed on good... and reports shall be in the English language. If any exhibit or other paper or document filed with...

  6. Interventions with vitamins B6, B12 and C in pregnancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The water-soluble vitamins B6, B12 and C play important roles in maternal health as well as fetal development and physiology during gestation. This systematic review evaluates the risks and benefits of interventions with vitamins B6, B12 and C during pregnancy on maternal, neonatal and child health ...

  7. Prevalence of vitamin B-12 deficiency among patients with thyroid dysfunction.

    PubMed

    Collins, Aryn B; Pawlak, Roman

    2016-01-01

    Due to the non-specificity of symptoms and possibly severe consequences of untreated vitamin B-12 deficiency, screening is important for at-risk patients to ensure the prompt delivery of treatment. In this review, studies assessing the prevalence of vitamin B-12 deficiency in thyroid dysfunction are evaluated to determine whether regular vitamin B-12 screening is necessary. A literature search was conducted using multiple electronic databases. Only original studies assessing the prevalence of vitamin B-12 deficiency in thyroid dysfunction that reported their findings as percentages of the sample were eligible for inclusion. From a total of 7091 manuscripts generated, 6 were included in this review. The prevalence of vitamin B-12 deficiency in hypothyroidism was reported as 10, 18.6, and 40.5% in three separate studies. The prevalence of deficiency in autoimmune thyroid disease was reported as 6.3, 28, and 55.5% in three studies. The prevalence of vitamin B-12 deficiency in hypothyroidism and autoimmune thyroid disease are reflective of the nutrition status of the population. Autoimmune thyroid disease is also associated with the autoimmune disorders pernicious anemia and atrophic gastritis which may lead to malabsorption of vitamin B-12. Vitamin B-12 screening is recommended upon initial diagnosis with autoimmune thyroid disease and then periodically thereafter. There is not enough evidence to recommend regular screening for patients with hypothyroidism unless the underlying cause is autoimmune thyroid disease.

  8. Oral Vitamin B12 Replacement for the Treatment of Pernicious Anemia.

    PubMed

    Chan, Catherine Qiu Hua; Low, Lian Leng; Lee, Kheng Hock

    2016-01-01

    Many patients with pernicious anemia are treated with lifelong intramuscular (IM) vitamin B12 replacement. As early as the 1950s, there were studies suggesting that oral vitamin B12 replacement may provide adequate absorption. Nevertheless, oral vitamin B12 replacement in patients with pernicious anemia remains uncommon in clinical practice. The objective of this review is to provide an update on the effectiveness of oral vitamin B12 for the treatment of pernicious anemia, the recommended dosage, and the required frequency of laboratory test and clinical monitoring. Relevant articles were identified by PubMed search from January 1, 1980 to March 31, 2016 and through hand search of relevant reference articles. Two randomized controlled trials, three prospective papers, one systematic review, and three clinical reviews fulfilled our inclusion criteria. We found that oral vitamin B12 replacement at 1000 μg daily was adequate to replace vitamin B12 levels in patients with pernicious anemia. We conclude that oral vitamin B12 is an effective alternative to vitamin B12 IM injections. Patients should be offered this alternative after an informed discussion on the advantages and disadvantages of both treatment options.

  9. If high folic acid aggravates vitamin B12 deficiency what should be done about it?

    PubMed

    Johnson, Mary Ann

    2007-10-01

    The most common cause of vitamin B12 deficiency in older people is malabsorption of food-bound vitamin B12. Thus, it is suggested that the recommended daily allowance of 2.4 microg/d be met primarily with crystalline vitamin B12, which is believed to be well absorbed in individuals who have food-bound malabsorption. There is concern that high intakes of folic acid from fortified food and dietary supplements might mask the macrocytic anemia of vitamin B12 deficiency, thereby eliminating an important diagnostic sign. One recent study indicates that high serum folate levels during vitamin B12 deficiency exacerbate (rather than mask) anemia and worsen cognitive symptoms. Another study suggests that once vitamin B12 deficiency is established in subjects with food-bound malabsorption, 40 microg/d to 80 microg/d of oral crystalline vitamin B12 for 30 d does not reverse the biochemical signs of deficiency. Together, these studies provide further evidence that public health strategies are needed to improve vitamin B12 status in order to decrease the risk of deficiency and any potentially adverse interactions with folic acid.

  10. Vitamin B12 and ageing: current issues and interaction with folate.

    PubMed

    Hughes, Catherine F; Ward, Mary; Hoey, Leane; McNulty, Helene

    2013-07-01

    A compromised vitamin B12 status is common in older people despite dietary intakes that typically far exceed current recommendations. The maintenance of an optimal status of vitamin B12 is not only dependent on adequate dietary intake but more critically on effective absorption which diminishes with age. The measurement of vitamin B12 is complicated by the lack of a gold standard assay. There are a number of direct and functional indicators of vitamin B12 status; however, none of these are without limitations and should be used in combination. Vitamin B12 is of public health importance, not only because deficiency leads to megaloblastic anaemia and irreversible nerve damage, but also because emerging evidence links low B12 to an increased risk of a number of age-related diseases, including cardiovascular disease, cognitive dysfunction, dementia and osteoporosis. Furthermore, there are concerns relating to potential adverse effects for older adults with low vitamin B12 status of over-exposure to folic acid in countries where there is mandatory fortification of food with folic acid. The aim of this review is to examine the known and emerging issues related to vitamin B12 in ageing, its assessment and inter-relationship with folate.

  11. Loss of vitamin B(12) in fish (round herring) meats during various cooking treatments.

    PubMed

    Nishioka, Michiko; Kanosue, Fuki; Yabuta, Yukinori; Watanabe, Fumio

    2011-01-01

    The loss of vitamin B(12) in round herring meats during various cooking treatments was evaluated. Although amounts of vitamin B(12) were three times greater in the viscera (37.5 ± 10.6 µg/100 g fresh weight) than in the meats, about 73% of total vitamin B(12) found in the whole fish body (except for head and bones) were recovered in the meats (5.1 ± 1.0 µg of vitamin B(12)). The vitamin B(12) contents of the round herring's meats were significantly decreased up to ~62% during cooking by grilling, boiling, frying, steaming, and microwaving. There was, however, no loss of vitamin B(12) during vacuum-packed pouch cooking. Model experiment using hydroxocobalamin suggest that loss of vitamin B(12) is dependent on the degree of temperature and time used in conventional cooking, and is further affected by the concomitant ingredients of food. Retention of vitamin B(12) was not dependent on vacuum or temperature (or both) used in the vacuum-packed pouch cooking.

  12. Vitamin B12 in obese adolescents with clinical features of insulin resistance.

    PubMed

    Ho, Mandy; Halim, Jocelyn H; Gow, Megan L; El-Haddad, Nouhad; Marzulli, Teresa; Baur, Louise A; Cowell, Chris T; Garnett, Sarah P

    2014-12-04

    Emerging evidence indicates an association between obesity, metformin use and reduced vitamin B12 status, which can have serious hematologic, neurologic and psychiatric consequences. This study aimed to examine B12 status in obese adolescents with pre-diabetes and/or clinical features of insulin resistance. Serum B12 was measured using chemiluminescence immunoassay in 103 (43 male, 60 female) obese (mean body mass index (BMI) z-score ± SD (2.36 ± 0.29)), adolescents aged 10 to 17 years, median (range) insulin sensitivity index of 1.27 (0.27 to 3.38) and 13.6% had pre-diabetes. Low B12 (<148 pmol/L) was identified in eight (7.8%) and borderline status (148 to 221 pmol/L) in an additional 25 (24.3%) adolescents. Adolescents with borderline B12 concentrations had higher BMI z-scores compared to those with normal concentrations (2.50 ± 0.22 vs. 2.32 ± 0.30, p = 0.008) or those with low B12 concentration (2.50 ± 0.22 vs. 2.27 ± 0.226, p = 0.041). In conclusion, nearly a third of obese adolescents with clinical insulin resistance had a low or borderline serum B12 status. Therefore, further investigations are warranted to explore the cause and the impact of low B12 status in obese pediatric populations.

  13. Synthesis, characterization and pharmacodynamics of vitamin-B(12)-conjugated glucagon-like peptide-1.

    PubMed

    Clardy-James, Susan; Chepurny, Oleg G; Leech, Colin A; Holz, George G; Doyle, Robert P

    2013-04-01

    Clearing the way: Glucagon-like peptide-1 (GLP-1) receptor agonists are proving a potent weapon in the treatment of type II diabetes. A new vitamin B(12)-GLP-1 conjugate is investigated and shown to have insulinotropic properties similar to the unmodified peptide. These results are critical to the exploitation of the vitamin B(12) oral uptake pathway for peptide delivery.

  14. Serum Vitamin B12 and thyroid hormone levels in Saudi patients with multiple sclerosis

    PubMed Central

    Al-Khamis, Fahd A.

    2016-01-01

    Objectives: To determine the relationship between Vitamin B12 levels and thyroid hormones in patients with multiple sclerosis (MS). Materials and Methods: One hundred and ten patients with MS were recruited for this study after Institutional Review Board approval. All patients signed a written informed consent form and donated a single blood sample. Plasma Vitamin B12 levels, triiodothyronine (T3), and thyroxine (T4) hormone levels were measured. Data were analyzed using the Statistical Package for Social Sciences (SPSS) software. Results: Analysis of Vitamin B12 levels in 110 patients with MS revealed that 65% had normal levels of Vitamin B12 (200–900 pg/ml), 30% had low levels of Vitamin B12 (<200 pg/ml), and 5% high levels of Vitamin B12 (higher than 900 pg/ml). Further analysis of patients with low levels of Vitamin B12 revealed that this cohort exhibited a significantly high number of patients with low levels of the thyroid hormones triiodothyronine (T3) and thyroxine (T4) (P < 0.005). Conclusion: This study suggests a relationship between Vitamin B12 levels and thyroid hormones. This opens the possibility that the use of therapies that increase triiodothyronine (T3) and thyroxine (T4) levels might be beneficial to patients with MS. PMID:27625581

  15. Uptake and transport of B12-conjugated nanoparticles in airway epithelium☆

    PubMed Central

    Fowler, Robyn; Vllasaliu, Driton; Falcone, Franco H.; Garnett, Martin; Smith, Bryan; Horsley, Helen; Alexander, Cameron; Stolnik, Snow

    2013-01-01

    Non-invasive delivery of biotherapeutics, as an attractive alternative to injections, could potentially be achieved through the mucosal surfaces, utilizing nanoscale therapeutic carriers. However, nanoparticles do not readily cross the mucosal barriers, with the epithelium presenting a major barrier to their translocation. The transcytotic pathway of vitamin B12 has previously been shown to ‘ferry’ B12-decorated nanoparticles across intestinal epithelial (Caco-2) cells. However, such studies have not been reported for the airway epithelium. Furthermore, the presence in the airways of the cell machinery responsible for transepithelial trafficking of B12 is not widely reported. Using a combination of molecular biology and immunostaining techniques, our work demonstrates that the bronchial cell line, Calu-3, expresses the B12-intrinsic factor receptor, the transcobalamin II receptor and the transcobalamin II carrier protein. Importantly, the work showed that sub-200 nm model nanoparticles chemically conjugated to B12 were internalised and transported across the Calu-3 cell layers, with B12 conjugation not only enhancing cell uptake and transepithelial transport, but also influencing intracellular trafficking. Our work therefore demonstrates that the B12 endocytotic apparatus is not only present in this airway model, but also transports ligand-conjugated nanoparticles across polarised epithelial cells, indicating potential for B12-mediated delivery of nanoscale carriers of biotherapeutics across the airways. PMID:24008152

  16. Folate and vitamin B12 status in Latin America and the Caribbean: An update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: The current magnitude of folate and vitamin B12 deficiency in Latin America and the Caribbean is uncertain. Objective: To summarize data on plasma or serum vitamin B12 and folate concentrations in Latin America and the Caribbean reported since 1990, a period that covers the era before an...

  17. Oral Vitamin B12 Replacement for the Treatment of Pernicious Anemia

    PubMed Central

    Chan, Catherine Qiu Hua; Low, Lian Leng; Lee, Kheng Hock

    2016-01-01

    Many patients with pernicious anemia are treated with lifelong intramuscular (IM) vitamin B12 replacement. As early as the 1950s, there were studies suggesting that oral vitamin B12 replacement may provide adequate absorption. Nevertheless, oral vitamin B12 replacement in patients with pernicious anemia remains uncommon in clinical practice. The objective of this review is to provide an update on the effectiveness of oral vitamin B12 for the treatment of pernicious anemia, the recommended dosage, and the required frequency of laboratory test and clinical monitoring. Relevant articles were identified by PubMed search from January 1, 1980 to March 31, 2016 and through hand search of relevant reference articles. Two randomized controlled trials, three prospective papers, one systematic review, and three clinical reviews fulfilled our inclusion criteria. We found that oral vitamin B12 replacement at 1000 μg daily was adequate to replace vitamin B12 levels in patients with pernicious anemia. We conclude that oral vitamin B12 is an effective alternative to vitamin B12 IM injections. Patients should be offered this alternative after an informed discussion on the advantages and disadvantages of both treatment options. PMID:27602354

  18. Daily milk intake improves vitamin B-12 status in young vegetarian Indians: an intervention trial

    PubMed Central

    2013-01-01

    Background Asymptomatic Indian lacto vegetarians, who make up more than half of the Indian population in different geographic regions, have distinctly low vitamin B-12 concentrations than non- vegetarians. Vegetarians consume milk but it seems that the amount is not enough to improve vitamin B-12 status or vitamin B-12 concentration in milk itself may be low. The aim of this study was to determine if daily milk consumption can improve vitamin B-12 status. Methods Fifteen male and 36 female, young healthy post-graduate volunteers participated. Blood from ten participants (4 males and 6 females) was collected (day-1). They continued their regular diet for next fourteen days and on day-15, blood of all 51 participants was collected, plasma vitamin B-12 concentration was measured and were divided into two groups; Normal (vitamin B-12 >148 pmol/L, n = 22) and Vitamin B-12 deficient (<148 pmol/L, n = 29), the remaining plasma was stored. All participants consumed 600 ml. of non-enriched buffalo milk (200 × 3) during the day along with their usual diet. Next day blood was collected for plasma holotranscobalamin II measurement. Subjects from deficient group continued to drink 400 ml of milk daily for next 14 days and blood was collected on day-30. Plasma holotranscoabalamin II (day-1, 15, 16, 30), vitamin B-12, folate, total homocysteine, creatinine and hematoloical parameters (day-1, 15, 30), and milk vitamin B-12 concentrations (day-15, 16, 30) were measured. Results Fifty seven per cent of the participants were vitamin B-12 deficient and 65% were hyperhomocysteinemic. No significant difference in biomarkers was observed when there was no intervention. Plasma holotranscobalamin II concentration increased from 19.6 to 22.27 pmol/L (p < 0.0001) 24 hrs after milk load in the whole group. Plasma vitamin B-12 increased from 92.5 to 122 pmol/L and tHcy concentrations decreased from 31.9 to 24.9 μ mol/L (p < 0.0001 for both) 14 days after regular milk

  19. Study on methane fermentation and production of vitamin B12 from alcohol waste slurry.

    PubMed

    Zhang, Zhenya; Quan, Taisheng; Li, Pomin; Zhang, Yansheng; Sugiura, Norio; Maekawa, Takaaki

    2004-01-01

    We studied biogas fermentation from alcohol waste fluid to evaluate the anaerobic digestion process and the production of vitamin B12 as a byproduct. Anaerobic digestion using acclimated methanogens was performed using the continuously stirred tank reactor (CSTR) and fixed-bed reactor packed with rock wool as carrier material at 55 degrees C. We also studied the effects of metal ions added to the culture broth on methane and vitamin B12 formation. Vitamin B12 production was 2.92 mg/L in the broth of the fixed-bed reactor, twice that of the CSTR. The optimum concentrations of trace metal ions added to the culture liquid for methane and vitamin B12 production were 1.0 and 8 mL/L for the CSTR and fixed-bed reactor, respectively. Furthermore, an effective method for extracting and purifying vitamin B12 from digested fluid was developed.

  20. An appraisal of the value of vitamin B12 in the prevention of motion sickness

    NASA Technical Reports Server (NTRS)

    Kohl, R. L.; Lacey, C. L.; Homick, J. L.

    1983-01-01

    It has been suggested that vitamin B12 given by intramuscular injection can significantly reduce the occurrence of motion sickness in susceptible individuals (Banks, 1980). Since it is known that B12 influences the metabolism of histidine and choline, dietary precursors to neurotransmitters with established roles in motion sickness, an experimental evaluation has been undertaken of the efficacy of B12 in the prevention of motion sickness induced by controlled coriolis simulation. Subjects executed standardized head movements at successively higher rpm until a malaise III endpoint was reached. Following two baseline tests with this motion stressor, subjects received a B12 injection, a second injection two weeks later, and a final motion sickness test three weeks later. No significant differences in the susceptibility to motion sickness were noted after B12.

  1. Stability of added and in situ-produced vitamin B12 in breadmaking.

    PubMed

    Edelmann, Minnamari; Chamlagain, Bhawani; Santin, Marco; Kariluoto, Susanna; Piironen, Vieno

    2016-08-01

    Vitamin B12 exists naturally in foods of animal origin and is synthesised only by certain bacteria. New food sources are needed to ensure vitamin B12 intake in risk groups. This study aimed to investigate the stability of added cyanocobalamin (CNCbl, chemically modified form) and hydroxocobalamin (OHCbl, natural form) and in situ-synthesised vitamin B12 in breadmaking. Samples were analysed both with a microbiological (MBA) and a liquid chromatographic (UHPLC) method to test applicability of these two methods. Proofing did not affect CNCbl and OHCbl levels. By contrast, 21% and 31% of OHCbl was lost in oven-baking steps in straight- and sponge-dough processes, respectively, whereas CNCbl remained almost stable. In sourdough baking, 23% of CNCbl and 44% of OHCbl were lost. In situ-produced vitamin B12 was almost as stable as added CNCbl and more stable than OHCbl. The UHPLC method showed its superiority to the MBA in determining the active vitamin B12.

  2. Vitamin B-12 treatment of asymptomatic, deficient, elderly Chileans improves conductivity in myelinated periphreal nerves, but high serum folate impairs vitamin B-12 status response assessed by the combined indicator of..

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2005 the National Feeding Program for the Elderly (PACAM) in Chile has provided a B12 fortified milk drink (1.7 µg B12/d) which is insufficient to ensure B12 adequacy in many individuals. The objective was to evaluate effects of adding 1 mg B12/d to PACAM vs 1 mg B12/d as a pill with PACAM on ...

  3. FRACTION OF TOTAL PLASMA VITAMIN B12 BOUND TO TRANSCOBALAMIN CORRELATES WITH COGNITIVE FUNCTION IN ELDERLY LATINOS WITH DEPRESSIVE SYMPTOMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: The fraction of total plasma vitamin B12 bound to transcobalamin (holoTC/B12 ratio) may reflect tissue levels of the vitamin, but its clinical relevance is unclear. Methods: associations between cognitive function and total B12, holoTC, and holoTC/B12 ratio were assessed in a cohort of ...

  4. Vitamin B12 and omega-3 fatty acids together regulate lipid metabolism in Wistar rats.

    PubMed

    Khaire, Amrita; Rathod, Richa; Kale, Anvita; Joshi, Sadhana

    2015-08-01

    Our recent study indicates that maternal vitamin B12 and omega-3 fatty acid status influence plasma and erythrocyte fatty acid profile in dams. The present study examines the effects of prenatal and postnatal vitamin B12 and omega-3 fatty acid status on lipid metabolism in the offspring. Pregnant dams were divided into five groups: Control; Vitamin B12 deficient (BD); Vitamin B12 supplemented (BS); Vitamin B12 deficient group supplemented with omega-3 fatty acids (BDO); Vitamin B12 supplemented group with omega-3 fatty acids (BSO). The offspring were continued on the same diets till 3 month of age. Vitamin B12 deficiency increased cholesterol levels (p<0.01) but reduced docosahexaenoic acid (DHA) (p<0.05), liver mRNA levels of acetyl CoA carboxylase-1 (ACC-1) (p<0.05) and carnitine palmitoyltransferase-1 (CPT-1) (p<0.01) in the offspring. Omega-3 fatty acid supplementation to this group normalized cholesterol but not mRNA levels of ACC-1 and CPT-1. Vitamin B12 supplementation normalized the levels cholesterol to that of control but increased plasma triglyceride (p<0.01) and reduced liver mRNA levels of adiponectin, ACC-1, and CPT-1 (p<0.01 for all). Supplementation of both vitamin B12 and omega-3 fatty acid normalized triglyceride and mRNA levels of all the above genes. Prenatal and postnatal vitamin B12 and omega-3 fatty acids together play a crucial role in regulating the genes involved in lipid metabolism in adult offspring.

  5. Long-term ovo-lacto vegetarian diet impairs vitamin B-12 status in pregnant women.

    PubMed

    Koebnick, Corinna; Hoffmann, Ingrid; Dagnelie, Pieter C; Heins, Ulrike A; Wickramasinghe, Sunitha N; Ratnayaka, Indrika D; Gruendel, Sindy; Lindemans, Jan; Leitzmann, Claus

    2004-12-01

    A well-planned vegetarian diet has been stated to be adequate during pregnancy. The aim of the present study was to compare serum vitamin B-12 and homocysteine concentrations in pregnant women (n = 109) consuming vegetarian and Western diets and to evaluate the adequacy of current dietary reference intakes of vitamin B-12 for these women. Pregnant women adhering to vegetarian diets for at least 3 y, with subgroups of ovo-lacto vegetarians (OLVs; n = 27), low-meat eaters (LME, n = 43), and women eating an average Western diet (control group, n = 39), were recruited. Dietary vitamin B-12 intake, serum vitamin B-12, and plasma total homocysteine (tHcy) concentrations were measured in wk 9-12, 20-22, and 36-38 of pregnancy. During pregnancy serum vitamin B-12 concentrations of ovo-lacto vegetarians (P < 0.001) and low-meat eaters (P = 0.050) were lower than those of the control group. We observed the combination of low serum vitamin B-12 concentrations and elevated plasma tHcy in 22% of ovo-lacto vegetarians, in 10% of low-meat eaters, and in 3% of controls (P = 0.003). In OLVs, serum vitamin B-12 predicted 60% of the plasma tHcy variation (P < 0.001), but in LMEs and controls only <10% (NS). Serum vitamin B-12 concentrations increased and plasma tHcy decreased sharply with increasing dietary intake of vitamin B-12 toward a cutoff point of 3 mug/d. Pregnant women consuming a long-term predominantly vegetarian diet have an increased risk of vitamin B-12 deficiency. Current recommended dietary intakes urgently need reevaluation.

  6. Efficacy and safety of fortification and supplementation with vitamin B12: biochemical and physiological effects.

    PubMed

    Carmel, Ralph

    2008-06-01

    Long known as an uncommon but serious medical disorder requiring medical management, vitamin B12 deficiency is now seen to be common worldwide, but it is in a quite different form than traditionally envisioned. Most of the newly recognized deficiency is subclinical in nature, its health impact and natural history are uncertain, and its prevalence has been greatly inflated by also including persons with "low-normal" vitamin B12 levels, few of whom are deficient. The spread of folic acid fortification has also introduced concerns about folate's potentially adverse neurologic consequences in persons with undetected vitamin B12 deficiency. Fortification with vitamin B12 may prove more complicated than fortification with folic acid, however, because the bioavailability of vitamin B12 is limited. Bioavailability for those who need the vitamin B12 the most is especially poor, because they often have malabsorption affecting either classical intrinsic factor-mediated absorption or food-vitamin B12 absorption. Moreover, new evidence shows that many elderly persons respond poorly to daily oral doses under 500 microg (1 microg = 0.74 nmol), even if they do not have classical malabsorption, which suggests that proposed fortification with 1 to 10 microg may be ineffective. Those least in need of vitamin B12 usually have normal absorption and are thus at greatest risk for whatever unknown adverse effects of high-dose fortification might emerge, such as the effects of excess accumulation of cyanocobalamin. Studies are needed to define the still unproven health benefits of vitamin B12 fortification, the optimal levels of fortification, the stability of such fortification, interactions with other nutrients, and any possible adverse effects on healthy persons. The answers will permit formulation of appropriately informed decisions about mandatory fortification or (because fortification may prove a poor choice) about targeted supplementation in subpopulations with special needs for

  7. A cost-effective sandwich electrochemiluminescence immunosensor for ultrasensitive detection of HIV-1 antibody using magnetic molecularly imprinted polymers as capture probes.

    PubMed

    Zhou, Jing; Gan, Ning; Li, Tianhua; Hu, Futao; Li, Xing; Wang, Lihong; Zheng, Lei

    2014-04-15

    In this report, a rapid and cost-effective sandwich electrochemiluminescence (ECL) immunosensor was constructed for the ultrasensitive detection of human immunodeficiency virus type 1 antibody (anti-HIV-1) using magnetic molecularly imprinted polymers (MMIPs) as capture probes by combining surface and epitope imprinting techniques and antigen conjugated with horseradish peroxidase (HRP-HIV-1) as labels. First, 3-aminobenzeneboronic acid (APBA) was used as the functional monomer and cross-linking reagent, which was polymerized on the surface of silicate-coated magnetic iron oxide nanoparticles (Fe3O4@SiO2 NPs) in the presence of human immunoglobulin G (HIgG), as the template exhibiting the same Fc region but different Fab region to anti-HIV-1 after the addition of the initiator, ammonium persulfate. This process resulted in grafting a hydrophilic molecularly imprinted polymer (MIP) film on the Fe3O4@SiO2 NPs. Thus, MMIPs, which could be reused after eluting the template, were used to recognize and enrich ultra-trace levels of anti-HIV-1. Subsequently, a novel sandwich ECL immunosensor was formed through the immunoreaction between MMIPs conjugated with varied concentrations of anti-HIV-1 and HRP-HIV-1. By the catalysis of HRP immobilized onto HRP-HIV-1 on the ECL system of Luminol-H2O2, a linear response range of the anti-HIV-1 dilution ratio (standard positive serum) was achieved from 1:20,000 to 1:50, with a detection limit of 1:60,000 (S/N=3). The developed method provides a low-cost, simple, and sensitive way for the early diagnosis of HIV infected patients.

  8. Genetic determinants of serum vitamin B12 and their relation to body mass index.

    PubMed

    Allin, Kristine H; Friedrich, Nele; Pietzner, Maik; Grarup, Niels; Thuesen, Betina H; Linneberg, Allan; Pisinger, Charlotta; Hansen, Torben; Pedersen, Oluf; Sandholt, Camilla H

    2016-12-19

    Lower serum vitamin B12 levels have been related to adverse metabolic health profiles, including adiposity. We used a Mendelian randomization design to test whether this relation might be causal. We included two Danish population-based studies (ntotal = 9311). Linear regression was used to test for associations between (1) serum vitamin B12 levels and body mass index (BMI), (2) genetic variants and serum vitamin B12 levels, and (3) genetic variants and BMI. The effect of a genetically determined decrease in serum vitamin B12 on BMI was estimated by instrumental variable regression. Decreased serum vitamin B12 associated with increased BMI (P < 1 × 10(-4)). A genetic risk score based on eight vitamin B12 associated variants associated strongly with serum vitamin B12 (P < 2 × 10(-43)), but not with BMI (P = 0.91). Instrumental variable regression showed that a 20% decrease in serum vitamin B12 was associated with a 0.09 kg/m(2) (95% CI 0.05; 0.13) increase in BMI (P = 3 × 10(-5)), whereas a genetically induced 20% decrease in serum vitamin B12 had no effect on BMI [-0.03 (95% CI -0.22; 0.16) kg/m(2)] (P = 0.74). Nevertheless, the strongest serum vitamin B12 variant, FUT2 rs602662, which was excluded from the B12 genetic risk score due to potential pleiotropic effects, showed a per allele effect of 0.15 kg/m(2) (95% CI 0.01; 0.32) on BMI (P = 0.03). This association was accentuated including two German cohorts (ntotal = 5050), with a combined effect of 0.19 kg/m(2) (95% CI 0.08; 0.30) (P = 4 × 10(-4)). We found no support for a causal role of decreased serum vitamin B12 levels in obesity. However, our study suggests that FUT2, through its regulation of the cross-talk between gut microbes and the human host, might explain a part of the observational association between serum vitamin B12 and BMI.

  9. Cubilin, the endocytic receptor for intrinsic factor-vitamin B(12) complex, mediates high-density lipoprotein holoparticle endocytosis.

    PubMed

    Hammad, S M; Stefansson, S; Twal, W O; Drake, C J; Fleming, P; Remaley, A; Brewer, H B; Argraves, W S

    1999-08-31

    Receptors that endocytose high-density lipoproteins (HDL) have been elusive. Here yolk-sac endoderm-like cells were used to identify an endocytic receptor for HDL. The receptor was isolated by HDL affinity chromatography and identified as cubilin, the recently described endocytic receptor for intrinsic factor-vitamin B(12). Cubilin antibodies inhibit HDL endocytosis by the endoderm-like cells and in mouse embryo yolk-sac endoderm, a prominent site of cubilin expression. Cubilin-mediated HDL endocytosis is inhibitable by HDL(2), HDL(3), apolipoprotein (apo)A-I, apoA-II, apoE, and RAP, but not by low-density lipoprotein (LDL), oxidized LDL, VLDL, apoC-I, apoC-III, or heparin. These findings, coupled with the fact that cubilin is expressed in kidney proximal tubules, suggest a role for this receptor in embryonic acquisition of maternal HDL and renal catabolism of filterable forms of HDL.

  10. L-chicoric acid, an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase, improves on the in vitro anti-HIV-1 effect of Zidovudine plus a protease inhibitor (AG1350).

    PubMed

    Robinson, W E

    1998-08-01

    Combinations of anti-human immunodeficiency virus (HIV) drugs, including reverse transcriptase inhibitors and protease inhibitors, have proven immensely potent in the therapy of acquired immune deficiency syndrome (AIDS). To determine whether HIV integrase is a suitable target for combination therapy, the ability of an HIV integrase inhibitor, L-chicoric acid, to work in combination with a protease inhibitor and Zidovudine was tested in vitro. The addition of L-chicoric acid to either Zidovudine or protease inhibitor improved upon the observed anti-HIV activity of either compound alone. When all three drugs were combined, the anti-HIV activity was substantially better than either of the three compounds alone or any combination of two inhibitors. Doses of both Zidovudine and protease inhibitor could be reduced by more than 33% for an equivalent anti-HIV effect if L-chicoric acid was added. The improved anti-HIV activity was observed with a tissue culture adapted strain of HIV (HIV(LAI)) and with limited passage clinical isolates of HIV (HIV(R19) and HIV(R45)). These data demonstrate that a first generation HIV integrase inhibitor, L-chicoric acid, is at least additive in combination with existing multi-drug regimens and suggest that HIV integrase will be an excellent target for combination therapy of HIV infection.

  11. Is vitamin B12 deficiency a risk factor for cardiovascular disease in vegetarians?

    PubMed

    Pawlak, Roman

    2015-06-01

    The goal of this paper is to describe the role of vitamin B12 deficiency in cardiovascular disease development among vegetarians. Vegetarians have a high prevalence of vitamin B12 deficiency. Deficiency of this vitamin is associated with a variety of atherogenic processes that are mainly, but not exclusively, due to vitamin B12 deficiency-induced hyperhomocysteinemia. Each 5-μmol/L increase above 10 μmol/L of serum homocysteine is associated with a 20% increased risk of circulatory health problems. Mean homocysteine concentration >10 μmol/L among vegetarians was reported in 32 of 34 reports. Macrocytosis associated with vitamin B12 deficiency is also associated with fatal and non-fatal coronary disease, myocardial infarction, stroke, and other circulatory health problems. Compared with non-vegetarians, vegetarians have an improved profile of the traditional cardiovascular disease risk factors, including serum lipids, blood pressure, serum glucose concentration, and weight status. However, not all studies that assessed cardiovascular disease incidence among vegetarians reported a protective effect. Among studies that did show a lower prevalence of circulatory health problems, the effect was not as pronounced as expected, which may be a result of poor vitamin B12 status due to a vegetarian diet. Vitamin B12 deficiency may negate the cardiovascular disease prevention benefits of vegetarian diets. In order to further reduce the risk of cardiovascular disease, vegetarians should be advised to use vitamin B12 supplements.

  12. Vitamin B(12) synthesis and salvage pathways were acquired by horizontal gene transfer to the Thermotogales.

    PubMed

    Swithers, Kristen S; Petrus, Amanda K; Secinaro, Michael A; Nesbø, Camilla L; Gogarten, J Peter; Noll, Kenneth M; Butzin, Nicholas C

    2012-01-01

    The availability of genome sequences of Thermotogales species from across the order allows an examination of the evolutionary origins of phenotypic characteristics in this lineage. Several studies have shown that the Thermotogales have acquired large numbers of genes from distantly related lineages, particularly Firmicutes and Archaea. Here, we report the finding that some Thermotogales acquired the ability to synthesize vitamin B(12) by acquiring the requisite genes from these distant lineages. Thermosipho species, uniquely among the Thermotogales, contain genes that encode the means to synthesize vitamin B(12) de novo from glutamate. These genes are split into two gene clusters: the corrinoid synthesis gene cluster, that is unique to the Thermosipho and the cobinamide salvage gene cluster. The corrinoid synthesis cluster was acquired from the Firmicutes lineage, whereas the salvage pathway is an amalgam of bacteria- and archaea-derived proteins. The cobinamide salvage gene cluster has a patchy distribution among Thermotogales species, and ancestral state reconstruction suggests that this pathway was present in the common Thermotogales ancestor. We show that Thermosipho africanus can grow in the absence of vitamin B(12), so its de novo pathway is functional. We detected vitamin B(12) in the extracts of T. africanus cells to verify the synthetic pathway. Genes in T. africanus with apparent B(12) riboswitches were found to be down-regulated in the presence of vitamin B(12) consistent with their roles in B(12) synthesis and cobinamide salvage.

  13. Vitamin B12 Synthesis and Salvage Pathways Were Acquired by Horizontal Gene Transfer to the Thermotogales

    PubMed Central

    Swithers, Kristen S.; Petrus, Amanda K.; Secinaro, Michael A.; Nesbø, Camilla L.; Gogarten, J. Peter; Noll, Kenneth M.; Butzin, Nicholas C.

    2012-01-01

    The availability of genome sequences of Thermotogales species from across the order allows an examination of the evolutionary origins of phenotypic characteristics in this lineage. Several studies have shown that the Thermotogales have acquired large numbers of genes from distantly related lineages, particularly Firmicutes and Archaea. Here, we report the finding that some Thermotogales acquired the ability to synthesize vitamin B12 by acquiring the requisite genes from these distant lineages. Thermosipho species, uniquely among the Thermotogales, contain genes that encode the means to synthesize vitamin B12 de novo from glutamate. These genes are split into two gene clusters: the corrinoid synthesis gene cluster, that is unique to the Thermosipho and the cobinamide salvage gene cluster. The corrinoid synthesis cluster was acquired from the Firmicutes lineage, whereas the salvage pathway is an amalgam of bacteria- and archaea-derived proteins. The cobinamide salvage gene cluster has a patchy distribution among Thermotogales species, and ancestral state reconstruction suggests that this pathway was present in the common Thermotogales ancestor. We show that Thermosipho africanus can grow in the absence of vitamin B12, so its de novo pathway is functional. We detected vitamin B12 in the extracts of T. africanus cells to verify the synthetic pathway. Genes in T. africanus with apparent B12 riboswitches were found to be down-regulated in the presence of vitamin B12 consistent with their roles in B12 synthesis and cobinamide salvage. PMID:22798452

  14. Neurology of Nutritional Vitamin B12 Deficiency in Infants: Case Series From India and Literature Review.

    PubMed

    Goraya, Jatinder Singh; Kaur, Sukhjot; Mehra, Bharat

    2015-11-01

    We studied 27 infants aged 6 to 27 months with vitamin B12 deficiency also known as "infantile tremor syndrome" in India. All were exclusively breast-fed by vegetarian mothers. Developmental delay or regression, pallor, skin hyperpigmentation, and sparse brown hair were present in all. Majority were hypotonic and involuntary movements were encountered in 18. Anemia and macrocytosis was found in 83% and 71% infants, respectively. Low serum vitamin B12 was present in 12 of 21 infants. Seven of the 9 infants with normal serum vitamin B12 had received vitamin B12 before referral. Twelve mothers had low serum vitamin B12. Cerebral atrophy was present in all the 9 infants who underwent neuroimaging. Treatment with vitamin B12 resulted in dramatic improvement in general activity and appetite within 48 to 72 hours followed by return of lost milestones. Tremors resolved in all by 3 to 4 weeks. Nutritional vitamin B12 deficiency is a treatable cause of neurologic dysfunction in infants.

  15. Mathematical Modeling of Glutathione Status in Type 2 Diabetics with Vitamin B12 Deficiency.

    PubMed

    Karamshetty, Varun; Acharya, Jhankar D; Ghaskadbi, Saroj; Goel, Pranay

    2016-01-01

    Deficiencies in vitamin B12 and glutathione (GSH) are associated with a number of diseases including type 2 diabetes mellitus. We tested newly diagnosed Indian diabetic patients for correlation between their vitamin B12 and GSH, and found it to be weak. Here we seek to examine the theoretical dependence of GSH on vitamin B12 with a mathematical model of 1-carbon metabolism due to Reed and co-workers. We study the methionine cycle of the Reed-Nijhout model by developing a simple "stylized model" that captures its essential topology and whose kinetics are analytically tractable. The analysis shows-somewhat counter-intuitively-that the flux responsible for the homeostasis of homocysteine is, in fact, peripheral to the methionine cycle. Elevation of homocysteine arises from reduced activity of methionine synthase, a vitamin B12-dependent enzyme, however, this does not increase GSH biosynthesis. The model suggests that the lack of vitamin B12-GSH correlation is explained by suppression of activity in the trans-sulfuration pathway that limits the synthesis of cysteine and GSH from homocysteine. We hypothesize this "cysteine-block" is an essential consequence of vitamin B12 deficiency. It can be clinically relevant to appreciate that these secondary effects of vitamin B12 deficiency could be central to its pathophysiology.

  16. Subjective well-being in older adults: folate and vitamin B12 independently predict positive affect.

    PubMed

    Edney, Laura C; Burns, Nicholas R; Danthiir, Vanessa

    2015-10-28

    Vitamin B12, folate and homocysteine have long been implicated in mental illness, and growing evidence suggests that they may play a role in positive mental health. Elucidation of these relationships is confounded due to the dependence of homocysteine on available levels of vitamin B12 and folate. Cross-sectional and longitudinal relationships between vitamin B12, folate, homocysteine and subjective well-being were assessed in a sample of 391 older, community-living adults without clinically diagnosed depression. Levels of vitamin B12, but not folate, influenced homocysteine levels 18 months later. Vitamin B12, folate and their interaction significantly predicted levels of positive affect (PA) 18 months later, but had no impact on the levels of negative affect or life satisfaction. Cross-sectional relationships between homocysteine and PA were completely attenuated in the longitudinal analyses, suggesting that the cross-sectional relationship is driven by the dependence of homocysteine on vitamin B12 and folate. This is the first study to offer some evidence of a causal link between levels of folate and vitamin B12 on PA in a large, non-clinical population.

  17. Possible undercompensation effect in the Kondo insulator (Yb,Tm)B12

    NASA Astrophysics Data System (ADS)

    Alekseev, P. A.; Nemkovski, K. S.; Mignot, J.-M.; Clementyev, E. S.; Ivanov, A. S.; Rols, S.; Bewley, R. I.; Filipov, V. B.; Shitsevalova, N. Yu.

    2014-03-01

    The effects of Tm substitution on the dynamical magnetic response of Yb1-xTmxB12 (x=0, 0.08, 0.15, and 0.75) and Lu0.92Tm0.08B12 compounds have been studied using time-of-flight inelastic neutron scattering. Major changes were observed in the spectral structure and temperature evolution of the Yb contribution to the inelastic response for a rather low content of magnetic Tm ions. A sizable influence of the RB12 host (YbB12, as compared to LuB12 or pure TmB12) on the crystal-field splitting of the Tm3+ ion is also reported. The results point to a specific effect of impurities carrying a magnetic moment (Tm, as compared to Lu or Zr) in a Kondo insulator, which is thought to reflect the "undercompensation" of Yb magnetic moments, originally Kondo screened in pure YbB12. A parallel is made with the strong effect of Tm substitution on the temperature dependence of the Seebeck coefficient in Yb1-xTmxB12, which was reported previously.

  18. Paraoxonase and arylesterase activities in adults with vitamin B12 deficiency.

    PubMed

    Guney, Tekin; Alisik, Murat; Alkan, Afra; Basturk, Abdulkadir; Akinci, Sema; Hacibekiroglu, Tuba; Dilek, Imdat; Erel, Ozcan

    2015-09-12

    Objective The purpose of this study was to investigate paraoxonase (PON) and arylesterase (ARES) enzyme activity in adults with vitamin B12 deficiency, and specific changes in the activities of these enzymes following vitamin B12 treatment. Methods A total of 46 patients with vitamin B12 deficiency (aged 18-82 years) and 45 healthy volunteer controls (aged 19-64 years) participated in this study. Venous blood samples were collected, and serum vitamin B12, homocysteine (HCY), methylmalonic acid, PON1, and ARES levels were measured. Results Paired comparison showed that pre- and post-treatment values for PON and ARES were similar between patients and controls (both P > 0.05). There was no statistically significant relationship between patients' pre-/post-treatment PON or HCY levels and serum vitamin B12 levels, compared with those of the control group (P > 0.05). Discussion The results of the present study do not support the hypothesis that the antioxidant enzymes PON and ARES have an underlying role in vitamin B12 deficiency and related hyperhomocysteinemia. Our findings suggest that PON and ARES do not play a role in the systemic effects of vitamin B12 deficiency.

  19. Intestinal synthesis and absorption of vitamin B-12 in channel catfish

    SciTech Connect

    Limsuwan, T.; Lovell, R.T.

    1981-12-01

    A feeding experiment conducted in a controlled environment and using a vitamin B12-deficient, but otherwise nutritionally complete, purified diet revealed that intestinal microorganisms in channel catfish synthesized approximately 1.4 ng of vitamin B12 per gram of bodyweight per day. Removal of cobalt from the diet or supplementation with an antibiotic (succinylsulfathiazole) significantly reduced the rate of intestinal synthesis and liver stores of vitamin B12. Radiolabeled vitamin B12 in the blood, liver, kidneys, and spleen of fish fed 60Co in the diet indicated that the intestinally synthesized vitamin was absorbed by the fish. The primary route of absorption was directly from the digestive tract into the blood because coprophagy was prevented in the rearing aquariums and the amount of vitamin B12 dissolved in the aquarium water was too low for gill absorption. Dietary supplementation of vitamin B12 was not necessary for normal growth and erythrocyte formation in channel catfish in a 24-week feeding period. A longer period, however, may have caused a vitamin deficiency since liver-stored vitamin B 12 decreased between the 2nd and 24th weeks.

  20. An appraisal of the value of vitamin B 12 in the prevention of motion sickness

    NASA Astrophysics Data System (ADS)

    Kohl, Randall L.; Lacey, Carol L.; Homick, Jerry L.

    Unpublished reports have suggested that hydroxycobalamin (B 12, i.m.) prevents motion sickness. Some biomedical evidence supports this contention in that B 12 influences the metabolism of histidine and choline; dietary precursors to neurotransmitters with established roles in motion sickness. Susceptibility to motion sickness was evaluated after B 12 (1000 μg, i.m.). Subjects initially completed vestibular function and motion sickness susceptibility tests to establish normal vestibular function. The experimental motion stressor was a modified coriolis sickness susceptibility test. Subjects executed standardized head movements at successively higher RPM until a malaise III endpoint was reached. Following two baseline tests with this motion stressor, subjects received a B 12 injection, a second injection two weeks later, and a final motion sickness test three weeks later. No significant differences in susceptibility were noted after B 12. Hematological parameters revealed no B 12 deficiency before injection. The possibility that patients with B 12 deficiencies are more susceptible to motion sickness cannot be ruled out.

  1. Obesity and insulin resistance associated with lower plasma vitamin B12 in PCOS.

    PubMed

    Kaya, Cemil; Cengiz, Sevim Dinçer; Satiroğlu, Hakan

    2009-11-01

    Polycystic ovary syndrome (PCOS) shares some or most components of metabolic cardiovascular syndrome, manifested by abdominal obesity, insulin resistance, dyslipidaemia and atherosclerosis. It has been previously demonstrated that folate and vitamin B(12) treatment improved insulin resistance in patients with metabolic syndrome. This study first investigated whether PCOS patients have lower or higher vitamin B(12), folate and homocysteine concentrations when compared with healthy, age and body mass index matched controls, and, then examined associations between vitamin B(12), folate, homocysteine and insulin resistance and obesity in PCOS patients. Homocysteine concentrations and homeostasis model assessment index were higher, whereas concentrations of vitamin B(12) were lower in PCOS patients with insulin resistance compared with those without insulin resistance. Serum vitamin B(12) concentrations were significantly lower in obese PCOS women in comparison with obese control women (P < 0.05). Fasting insulin, insulin resistance and homocysteine are independent determinants of serum vitamin B(12) concentrations in PCOS patients. Insulin resistance, obesity, and elevated homocysteine were associated with lower serum vitamin B(12) concentrations in PCOS patients.

  2. Mathematical Modeling of Glutathione Status in Type 2 Diabetics with Vitamin B12 Deficiency

    PubMed Central

    Karamshetty, Varun; Acharya, Jhankar D.; Ghaskadbi, Saroj; Goel, Pranay

    2016-01-01

    Deficiencies in vitamin B12 and glutathione (GSH) are associated with a number of diseases including type 2 diabetes mellitus. We tested newly diagnosed Indian diabetic patients for correlation between their vitamin B12 and GSH, and found it to be weak. Here we seek to examine the theoretical dependence of GSH on vitamin B12 with a mathematical model of 1-carbon metabolism due to Reed and co-workers. We study the methionine cycle of the Reed-Nijhout model by developing a simple “stylized model” that captures its essential topology and whose kinetics are analytically tractable. The analysis shows—somewhat counter-intuitively—that the flux responsible for the homeostasis of homocysteine is, in fact, peripheral to the methionine cycle. Elevation of homocysteine arises from reduced activity of methionine synthase, a vitamin B12-dependent enzyme, however, this does not increase GSH biosynthesis. The model suggests that the lack of vitamin B12–GSH correlation is explained by suppression of activity in the trans-sulfuration pathway that limits the synthesis of cysteine and GSH from homocysteine. We hypothesize this “cysteine-block” is an essential consequence of vitamin B12 deficiency. It can be clinically relevant to appreciate that these secondary effects of vitamin B12 deficiency could be central to its pathophysiology. PMID:27047940

  3. Blood folic acid, vitamin B12, and homocysteine levels in pregnant women with fetal growth restriction.

    PubMed

    Jiang, H L; Cao, L Q; Chen, H Y

    2016-12-19

    Deficiencies in nutrients such as folic acid and vitamin B12 may play a role in fetal growth restriction (FGR). However, whether folic acid, vitamin B12, or homocysteine is associated with FGR in Chinese populations remains unclear. This study investigated the relationship between these nutrient deficiencies and FGR in pregnant Chinese women. We selected 116 mother and infant pairs, and categorized the neonates into the FGR, appropriate for gestational age, and large for gestational age groups. Birth weight, body length, head circumference, body mass index (BMI), and Rohrer's body index of the newborns were measured. Serum folic acid, vitamin B12, and homocysteine levels were measured in mothers during the first three days of their hospital stay. Results showed that the FGR group exhibited reduced folic acid and vitamin B12 levels and elevated homocysteine levels than those in the other two groups. Folic acid and vitamin B12 levels were positively correlated with birth weight, head circumference, and BMI, whereas homocysteine level was negatively correlated with these variables. The FGR ratio in the folic acid and vitamin B12 deficiency group was higher than that in the sufficiency group (χ(2) = 4.717 and 4.437, P = 0.029 and 0.035, respectively). In addition, elevated homocysteine was associated with FGR (χ(2) = 5.366, P = 0.021). In conclusion, we found that folic acid and vitamin B12 deficiency was associated with elevated homocysteine levels, which may increase susceptibility to FGR.

  4. [Cyanide with vitamin B12 deficiency as the cause of experimental tobacco amblyopia].

    PubMed

    Oku, H; Fukushima, K; Miyata, M; Wakakura, M; Ishikawa, S

    1991-02-01

    The visual toxicity of tobacco smoke was studied and demyelination change of retrobulbar portion of the rat's optic nerve with an elongation of a peak latency time of visual evoked potentials (VEP) was demonstrated. Cyanide detoxication incapacity and deficiency of vitamin B12 (B12) have been considered as possible causes of tobacco amblyopia. In order to elucidate an influence of cyanide poisoning and B12 deficiency on the visual system, 12 male Wistar rats were subjected to 5 hour's daily inhalation of cyanide gas for 52 weeks, the concentration of which was adjusted to that of tobacco smoke. Six rats of these 12 were fed with a lacking B12 diet. Another 12 male Wistar rats were controls which did not undergo inhalation of cyanide gas, and half of them were fed a diet without B12. In 2 out of 6 rats with cyanide and inhalation and B12 deficiency, demyelination change could be recognized in the central portion of the retrobulbar optic nerve. The histological change was segmental and significant elongation of the peak latency time of VEP was not recognized. Cyanide gas inhalation at a low concentration was proved to be harmful to the optic nerve under the condition of B12 deficiency, but other toxic elements such as nicotine and carbon monoxide may be important factors to cause the more severe changes of the optic nerve with an abnormal VEP response recognized in the experimental tobacco amblyopia.

  5. Vitamin B12, folate, homocysteine and urinary methylmalonic acid levels in infants.

    PubMed

    Karademir, F; Suleymanoglu, S; Ersen, A; Aydinoz, S; Gultepe, M; Meral, C; Ozkaya, H; Gocmen, I

    2007-01-01

    Serum vitamin B12 and folate, and their functional markers, plasma homocysteine and urinary methylmalonate (uMMA) were measured in 204 healthy, term infants at birth, and at 2 and 6 months. Compared with infants receiving formula food, those fed mother's milk had lower vitamin B12 and folate at 2 and 6 months. In infants receiving mother's milk, vitamin B12 levels were similar at birth (238 pg/ml) and 2 months (243 pg/ml), whereas with formula milk the level was significantly higher at 2 months (558 pg/ml) than at birth (257 pg/ml). Vitamin B12 was negatively correlated with homocysteine at birth and 6 months. The level of uMMA (mmol/mol creatinine) was higher at 2 (mother's milk, 25.5; formula, 23.97) and 6 months (19.77; 15) than at birth (11.97; 10.88), and was not correlated with vitamin B12 levels. Homocysteine may be a reliable marker of vitamin B12 status in neonates and infants; however, uMMA is not suitable as a marker of vitamin B12 status.

  6. [Maternal Crohn's disease-related vitamin B12 deficient megaloblastic anemia in an infant].

    PubMed

    Ohyama, Wataru; Yamaoka, Masayoshi; Yokoi, Kentaro; Iwahashi, Megumi; Inage, Yuka; Arihiro, Seiji; Koganei, Kazutaka; Sugita, Akira; Ida, Hiroyuki; Akiyama, Masaharu

    2016-01-01

    We report an 11-month-old breast-fed boy with feeding difficulties, lethargy, and developmental delay. Blood examination showed pancytopenia and decreased serum levels of vitamin B12. Anisocytosis and poikilocytes were detected in his peripheral blood, and increased megaloblastosis without leukemic cells was detected in his bone marrow. After the diagnosis of megaloblastic anemia due to vitamin B12 deficiency, symptoms were improved by vitamin B12 administration. Further investigation of the mother identified Crohn's disease and suggested that the supply of vitamin B12 from the mother to the infant, via the placenta during pregnancy and via breast milk after birth, was decreased due to impaired absorption of vitamin B12 in the mother's small intestine. Magnetic resonance imaging of the boy's brain on admission showed cerebral cortex atrophy which had improved by the age of 1 year and 10 months after vitamin B12 treatment, though developmental delay was still evident at the age of 3 years. Infantile vitamin B12 deficiency often presents with nonspecific manifestations, such as developmental delay and failure to thrive, in addition to anemia and is thus not easily diagnosed. To prevent severe neurological sequelae, this condition must be rapidly diagnosed, because a prolonged duration increases the risk of permanent disabilities.

  7. High Prevalence of Vitamin B12 Deficiency and No Folate Deficiency in Young Children in Nepal

    PubMed Central

    Ng’eno, Bernadette N.; Perrine, Cria G.; Whitehead, Ralph D.; Subedi, Giri Raj; Mebrahtu, Saba; Dahal, Pradiumna; Jefferds, Maria Elena D.

    2017-01-01

    Many children in low- and middle-income countries may have inadequate intake of vitamin B12 and folate; data confirming these inadequacies are limited. We used biochemical, demographic, behavioral and anthropometric data to describe the folate and vitamin B12 concentrations among six- to 23-month-old Nepalese children. Vitamin B12 (serum B12 < 150 pmol/L) and folate deficiencies (red blood cell (RBC) folate < 226.5 nmol/L) were assessed. We used logistic regression to identify predictors of vitamin B12 deficiency. The vitamin B12 geometric mean was 186 pmol/L; 30.2% of children were deficient. The mean RBC folate concentration was 13,612 nmol/L; there was no deficiency. Factors associated with vitamin B12 deficiency included: (a) age six to 11 months (adjusted odds ratio (aOR) 1.51; 95% confidence interval (CI): 1.18, 1.92) or 12–17 months (aOR 1.38; 95% CI: 1.10, 1.72) compared to 18–23 months; (b) being stunted (aOR 1.24; 95% CI: 1.03, 1.50) compared to not being stunted; (c) and not eating animal-source foods (aOR 1.85; 95% CI: 1.42, 2.41) compared to eating animal-source foods the previous day. There was a high prevalence of vitamin B12 deficiency, but no folate deficiency. Improving early feeding practices, including the consumption of rich sources of vitamin B12, such as animal-source foods and fortified foods, may help decrease deficiency. PMID:28106733

  8. Therapeutic role of Vitamin B12 in patients of chronic tinnitus: A pilot study.

    PubMed

    Singh, Charu; Kawatra, Rahul; Gupta, Jaya; Awasthi, Vishnu; Dungana, Homnath

    2016-01-01

    True tinnitus is a phantom auditory perception arising from a source or trigger in the cochlea, brainstem, or at higher centers and has no detectable acoustic generator. The most accepted is the famous neurophysiologic model of Jastreboff, which stresses that tinnitus, is a subcortical perception and results from the processing of weak neural activity in the periphery. The aim of this study is to determine the role of Vitamin B12 in treatment of chronic tinnitus. In this randomized, double-blind pilot study, total 40 patients were enrolled, of which 20 in Group A (cases) received intramuscular therapy of 1 ml Vitamin B12 (2500 mcg) weekly for a period of 6 weeks and Group B (20) patients received placebo isotonic saline 01 ml intramuscular. The patients were subjected to Vitamin B12 assay and audiometry pre- and post-therapy. Of the total patients of tinnitus, 17 were Vitamin B12 deficient that is 42.5% showed deficiency when the normal levels were considered to be 250 pg/ml. A paired t-test showed that in Group A, patients with Vitamin B12 deficiency showed significant improvement in mean tinnitus severity index score and visual analog scale (VAS) after Vitamin B12 therapy. This pilot study highlights the significant prevalence of Vitamin B12 deficiency in North Indian population and improvement in tinnitus severity scores and VAS in cobalamin-deficient patients receiving intramuscular Vitamin B12 weekly for 6 weeks further provides a link between cobalamin deficiency and tinnitus thereby suggestive of a therapeutic role of B12 in cobalamin-deficient patients of tinnitus.

  9. STM investigations of Au(1 1 1) electrodes coated with vitamin B 12 derivatives

    NASA Astrophysics Data System (ADS)

    Szőcs, E.; Durrer, L.; Luginbühl, R.; Simic, N.; Viana, A. S.; Abrantes, L. M.; Keese, R.; Siegenthaler, H.

    2006-01-01

    Vitamin B 12 derivatives immobilized at flame-annealed Au(1 1 1) electrode surfaces have been investigated in close correlation with their structural properties and spatial arrangement at the electrode substrate by scanning tunneling microscopy (STM) in air and in aqueous 0.1 M NaClO 4 solution. The investigated compounds were symmetrical (B 12C 10S-SC 10B 12) and nonsymmetrical (B 12C 10S-SC 10) dialkyl disulfide derivatives of vitamin B 12, attached to the electrode surfaces by the S-Au bond. The ex situ and in situ STM experiments show the formation of a surface layer, whose packing density and structure is presumably controlled by the spatial arrangement of the large cobyrinate head groups. In presence of the symmetrical B 12 compound, a disordered surface layer is observed. Voltammetric investigations show that, in 0.1 M NaClO 4, this layer becomes unstable at potentials approximately ⩽ -1000 mV vs. MSE and is almost completely removed at more negative potentials. The STM imaging properties of the nonsymmetrical B 12 surface layer show a significant dependence on the tunneling distance. In particular, at small tunneling distances, a highly regular hexagonal surface pattern is observed that suggests strongly the presence of an ordered surface assembly. Modeling of the B 12 head group has been performed to provide information for a structure-related interpretation of the high-resolution STM images. The investigations are first STM results obtained at such B 12 modified electrodes.

  10. High Prevalence of Vitamin B12 Deficiency and No Folate Deficiency in Young Children in Nepal.

    PubMed

    Ng'eno, Bernadette N; Perrine, Cria G; Whitehead, Ralph D; Subedi, Giri Raj; Mebrahtu, Saba; Dahal, Pradiumna; Jefferds, Maria Elena D

    2017-01-17

    Many children in low- and middle-income countries may have inadequate intake of vitamin B12 and folate; data confirming these inadequacies are limited. We used biochemical, demographic, behavioral and anthropometric data to describe the folate and vitamin B12 concentrations among six- to 23-month-old Nepalese children. Vitamin B12 (serum B12 < 150 pmol/L) and folate deficiencies (red blood cell (RBC) folate < 226.5 nmol/L) were assessed. We used logistic regression to identify predictors of vitamin B12 deficiency. The vitamin B12 geometric mean was 186 pmol/L; 30.2% of children were deficient. The mean RBC folate concentration was 13,612 nmol/L; there was no deficiency. Factors associated with vitamin B12 deficiency included: (a) age six to 11 months (adjusted odds ratio (aOR) 1.51; 95% confidence interval (CI): 1.18, 1.92) or 12-17 months (aOR 1.38; 95% CI: 1.10, 1.72) compared to 18-23 months; (b) being stunted (aOR 1.24; 95% CI: 1.03, 1.50) compared to not being stunted; (c) and not eating animal-source foods (aOR 1.85; 95% CI: 1.42, 2.41) compared to eating animal-source foods the previous day. There was a high prevalence of vitamin B12 deficiency, but no folate deficiency. Improving early feeding practices, including the consumption of rich sources of vitamin B12, such as animal-source foods and fortified foods, may help decrease deficiency.

  11. Therapeutic role of Vitamin B12 in patients of chronic tinnitus: A pilot study

    PubMed Central

    Singh, Charu; Kawatra, Rahul; Gupta, Jaya; Awasthi, Vishnu; Dungana, Homnath

    2016-01-01

    True tinnitus is a phantom auditory perception arising from a source or trigger in the cochlea, brainstem, or at higher centers and has no detectable acoustic generator. The most accepted is the famous neurophysiologic model of Jastreboff, which stresses that tinnitus, is a subcortical perception and results from the processing of weak neural activity in the periphery. The aim of this study is to determine the role of Vitamin B12 in treatment of chronic tinnitus. In this randomized, double-blind pilot study, total 40 patients were enrolled, of which 20 in Group A (cases) received intramuscular therapy of 1 ml Vitamin B12 (2500 mcg) weekly for a period of 6 weeks and Group B (20) patients received placebo isotonic saline 01 ml intramuscular. The patients were subjected to Vitamin B12 assay and audiometry pre- and post-therapy. Of the total patients of tinnitus, 17 were Vitamin B12 deficient that is 42.5% showed deficiency when the normal levels were considered to be 250 pg/ml. A paired t-test showed that in Group A, patients with Vitamin B12 deficiency showed significant improvement in mean tinnitus severity index score and visual analog scale (VAS) after Vitamin B12 therapy. This pilot study highlights the significant prevalence of Vitamin B12 deficiency in North Indian population and improvement in tinnitus severity scores and VAS in cobalamin-deficient patients receiving intramuscular Vitamin B12 weekly for 6 weeks further provides a link between cobalamin deficiency and tinnitus thereby suggestive of a therapeutic role of B12 in cobalamin-deficient patients of tinnitus. PMID:26960786

  12. Pernicious anemia presenting as catatonia: correlating vitamin B12 levels and catatonic symptoms.

    PubMed

    Bram, Damien; Bubrovszky, Maxime; Durand, Jean-Paul; Lefevre, Guillaume; Morell-Dubois, Sandrine; Vaiva, Guillaume

    2015-01-01

    Pernicious anemia has been associated with various psychiatric manifestations, such as depression, mania and psychosis. Psychiatric symptoms can sometimes occur without hematological and neurological abnormalities and can be prodromal of vitamin B12 deficiency. We report a case of autoimmune B12 deficiency presenting as catatonia without signs of anemia or macrocytosis, in which a correlation was found between the patient's B12 blood levels and catatonic symptoms over time. This catatonic episode was successfully treated with only lorazepam and adequate doses of cyanocobalamin.

  13. Anti-AIDS agents 85. Design, synthesis, and evaluation of 1R,2R-dicamphanoyl-3,3-dimethyldihydropyrano-[2,3-c]xanthen-7(1H)-one (DCX) derivatives as novel anti-HIV agents

    PubMed Central

    Zhou, Ting; Shi, Qian; Chen, Chin-Ho; Huang, Li; Ho, Phong; Morris-Natschke, Susan L.; Lee, Kuo-Hsiung

    2011-01-01

    In this study, 1R,2R-dicamphanoyl-3,3-dimethydihydropyrano[2,3-c]xanthen-7(1H)-one (DCX) derivatives were designed and synthesized as novel anti-HIV agents against both wild-type and nonnucleoside reverse transcriptase (RT) inhibitor-resistant HIV-1 (RTMDR-1) strains. Twenty-four DCX analogs (6-29) were synthesized and evaluated against the non-drug-resistant HIV-1 NL4-3 strain, and selected analogs were also screened for their ability to inhibit the RTMDR-1 strain. Compared with the control 2-ethyl-3′,4′-di-O-(-)-camphanoyl-2′,2′-dimethyldihydropyrano[2,3-f]chromone (2-EDCP, 2), one of the best anti-HIV coumarin derivatives in our prior study, three DCX compounds (7, 12, and 22) showed better activity against both HIV strains with an EC50 range of 0.062 – 0.081 μM, and five additional compounds (8, 11, 16, 18, and 21) exhibited comparable anti-HIV potency. Six DCX analogs (7, 11-12, 18, and 21-22) also showed enhanced selectivity index (SI) values in comparison to the control. Structure-activity relationship (SAR) information suggested that the extended conjugated system of the pyranoxanthone skeleton facilitates the interaction of the small DCX molecule within the viral binding pocket, consequently leading to enhanced anti-HIV activity and selectivity. Compared to DCP compounds, DCX analogs are a more promising new class of anti-HIV agents. PMID:22063755

  14. Bioactivation to an aldehyde metabolite--possible role in the onset of toxicity induced by the anti-HIV drug abacavir.

    PubMed

    Grilo, Nádia M; Charneira, Catarina; Pereira, Sofia A; Monteiro, Emília C; Marques, M Matilde; Antunes, Alexandra M M

    2014-01-30

    Aldehydes are highly reactive molecules, which can be generated during numerous physiological processes, including the biotransformation of drugs. Several non-P450 enzymes participate in their metabolism albeit alcohol dehydrogenase and aldehyde dehydrogenase are the ones most frequently involved in this process. Endogenous and exogenous aldehydes have been strongly implicated in multiple human pathologies. Their ability to react with biomacromolecules (e.g. proteins) yielding covalent adducts is suggested to be the common primary mechanism underlying the toxicity of these reactive species. Abacavir is one of the options for combined anti-HIV therapy. Although individual susceptibilities to adverse effects differ among patients, abacavir is associated with idiosyncratic hypersensitivity drug reactions and an increased risk of cardiac dysfunction. This review highlights the current knowledge on abacavir metabolism and discusses the potential role of bioactivation to an aldehyde metabolite, capable of forming protein adducts, in the onset of abacavir-induced toxic outcomes.

  15. Note on the formulation of thermosensitive and mucoadhesive vaginal hydrogels containing the miniCD4 M48U1 as anti-HIV-1 microbicide.

    PubMed

    Bouchemal, Kawthar; Frelichowska, Justyna; Martin, Loïc; Lievin-Le Moal, Vanessa; Le Grand, Roger; Dereuddre-Bosquet, Nathalie; Djabourov, Madeleine; Aka-Any-Grah, Armelle; Koffi, Armand; Ponchel, Gilles

    2013-10-01

    The miniCD4 M48U1 was formulated into thermosensitive and mucoadhesive pluronic(®) hydrogels as anti-HIV-1 microbicide. The release kinetics of M48U1 from F127/HPMC (20/1 wt%) and F127/F68/HPMC (22.5/2.5/1 wt%) studied during 24h by using Franz diffusion cells showed that HEC hydrogel (1.5 wt%) used as control released 93% of the peptide, while about 25% of M48U1 remained in pluronic(®) hydrogels. The formulation of M48U1 in pluronic(®) hydrogels ensures a local delivery because no diffusion of the peptide was detected through vaginal Cynomolgus macaque mucosa using Ussing chamber. Finally, toxicological studies showed no significant difference in the HeLa cell viability of the pluronic(®) hydrogels in comparison with HEC and phosphate buffer saline.

  16. LC-MS/MS structural characterization of stress degradation products including the development of a stability indicating assay of Darunavir: An anti-HIV drug.

    PubMed

    Rao, R Nageswara; Ramachandra, B; Sravan, B; Khalid, Sara

    2014-02-01

    Darunavir, an anti-HIV drug was subjected to forced degradation under acid, base, thermal and neutral hydrolysis, oxidation and photolysis as prescribed by ICH guidelines. Four major degradation products were formed under acid and base hydrolysis, while stable under neutral and thermal hydrolysis, oxidative and photolysis. The drug and its degradation products were separated on Hiber, LiChrospher® 60, RP-select B, C8 column (250mm×4.6mm i.d., 5μm) using 10mM ammonium acetate: acetonitrile (52:48, v/v) as mobile phase in an isocratic elution mode by LC. The degradation products were characterized by LC-MS/MS and fragmentation pathways were proposed. The proposed structures of degradation products were confirmed by HRMS and the LC method was validated with respect to specificity, linearity, accuracy, recovery, LOD and LOQ.

  17. A new activity of anti-HIV and anti-tumor protein GAP31: DNA adenosine glycosidase - Structural and modeling insight into its functions

    SciTech Connect

    Li, Hui-Guang; Huang, Philip L.; Zhang, Dawei; Sun, Yongtao; Chen, Hao-Chia; Zhang, John; Huang, Paul L.; Kong, Xiang-Peng; Lee-Huang, Sylvia

    2010-01-01

    We report here the high-resolution atomic structures of GAP31 crystallized in the presence of HIV-LTR DNA oligonucleotides systematically designed to examine the adenosine glycosidase activity of this anti-HIV and anti-tumor plant protein. Structural analysis and molecular modeling lead to several novel findings. First, adenine is bound at the active site in the crystal structures of GAP31 to HIV-LTR duplex DNA with 5' overhanging adenosine ends, such as the 3'-processed HIV-LTR DNA but not to DNA duplex with blunt ends. Second, the active site pocket of GAP31 is ideally suited to accommodate the 5' overhanging adenosine of the 3'-processed HIV-LTR DNA and the active site residues are positioned to perform the adenosine glycosidase activity. Third, GAP31 also removes the 5'-end adenine from single-stranded HIV-LTR DNA oligonucleotide as well as any exposed adenosine, including that of single nucleotide dAMP but not from AMP. Fourth, GAP31 does not de-purinate guanosine from di-nucleotide GT. These results suggest that GAP31 has DNA adenosine glycosidase activity against accessible adenosine. This activity is distinct from the generally known RNA N-glycosidase activity toward the 28S rRNA. It may be an alternative function that contributes to the antiviral and anti-tumor activities of GAP31. These results provide molecular insights consistent with the anti-HIV mechanisms of GAP31 in its inhibition on the integration of viral DNA into the host genome by HIV-integrase as well as irreversible topological relaxation of the supercoiled viral DNA.

  18. A New Activity of Anti-HIV and Anti-tumor Protein GAP31: DNA Adenosine Glycosidase – Structural and Modeling Insight into its Functions

    SciTech Connect

    Li, H.; Huang, P; Zhang, D; Sun, Y; Chen, H; Zhang, J; Huang, P; Kong, X; Lee-Huang, S

    2010-01-01

    We report here the high-resolution atomic structures of GAP31 crystallized in the presence of HIV-LTR DNA oligonucleotides systematically designed to examine the adenosine glycosidase activity of this anti-HIV and anti-tumor plant protein. Structural analysis and molecular modeling lead to several novel findings. First, adenine is bound at the active site in the crystal structures of GAP31 to HIV-LTR duplex DNA with 5' overhanging adenosine ends, such as the 3'-processed HIV-LTR DNA but not to DNA duplex with blunt ends. Second, the active site pocket of GAP31 is ideally suited to accommodate the 5' overhanging adenosine of the 3'-processed HIV-LTR DNA and the active site residues are positioned to perform the adenosine glycosidase activity. Third, GAP31 also removes the 5'-end adenine from single-stranded HIV-LTR DNA oligonucleotide as well as any exposed adenosine, including that of single nucleotide dAMP but not from AMP. Fourth, GAP31 does not de-purinate guanosine from di-nucleotide GT. These results suggest that GAP31 has DNA adenosine glycosidase activity against accessible adenosine. This activity is distinct from the generally known RNA N-glycosidase activity toward the 28S rRNA. It may be an alternative function that contributes to the antiviral and anti-tumor activities of GAP31. These results provide molecular insights consistent with the anti-HIV mechanisms of GAP31 in its inhibition on the integration of viral DNA into the host genome by HIV-integrase as well as irreversible topological relaxation of the supercoiled viral DNA.

  19. A novel gene therapy strategy using secreted multifunctional anti-HIV proteins to confer protection to gene-modified and unmodified target cells.

    PubMed

    Falkenhagen, A; Ameli, M; Asad, S; Read, S E; Joshi, S

    2014-02-01

    Current human immunodeficiency virus type I (HIV) gene therapy strategies focus on rendering HIV target cells non-permissive to viral replication. However, gene-modified cells fail to accumulate in patients and the virus continues to replicate in the unmodified target cell population. We have designed lentiviral vectors encoding secreted anti-HIV proteins to protect both gene-modified and unmodified cells from infection. Soluble CD4 (sCD4), a secreted single chain variable fragment (sscFv(17b)) and a secreted fusion inhibitor (sFI(T45)) were used to target receptor binding, co-receptor binding and membrane fusion, respectively. Additionally, we designed bi- and tri-functional fusion proteins to exploit the multistep nature of HIV entry. Of the seven antiviral proteins tested, sCD4, sCD4-scFv(17b), sCD4-FI(T45) and sCD4-scFv(17b)-FI(T45) efficiently inhibited HIV entry. The neutralization potency of the bi-functional fusion proteins sCD4-scFv(17b) and sCD4-FI(T45) was superior to that of sCD4 and the Food and Drug Administration-approved fusion inhibitor T-20. In co-culture experiments, sCD4, sCD4-scFv(17b) and sCD4-FI(T45) secreted from gene-modified producer cells conferred substantial protection to unmodified peripheral blood mononuclear cells. In conclusion, continuous delivery of secreted anti-HIV proteins via gene therapy may be a promising strategy to overcome the limitations of the current treatment.

  20. The in vitro ejection of zinc from human immunodeficiency virus (HIV) type 1 nucleocapsid protein by disulfide benzamides with cellular anti-HIV activity.

    PubMed Central

    Tummino, P J; Scholten, J D; Harvey, P J; Holler, T P; Maloney, L; Gogliotti, R; Domagala, J; Hupe, D

    1996-01-01

    Several disulfide benzamides have been shown to possess wide-spectrum antiretroviral activity in cell culture at low micromolar to submicromolar concentrations, inhibiting human immunodeficiency virus (HIV) type 1 (HIV-1) clinical and drug-resistant strains along with HIV-2 and simian immunodeficiency virus [Rice, W. G., Supko, J. G., Malspeis, L., Buckheit, R. W., Jr., Clanton, D., Bu, M., Graham, L., Schaeffer, C. A., Turpin, J. A., Domagala, J., Gogliotti, R., Bader, J. P., Halliday, S. M., Coren, L., Sowder, R. C., II, Arthur, L. O. & Henderson, L. E. (1995) Science 270, 1194-1197]. Rice and coworkers have proposed that the compounds act by "attacking" the two zinc fingers of HIV nucleocapsid protein. Shown here is evidence that low micromolar concentrations of the anti-HIV disulfide benzamides eject zinc from HIV nucleocapsid protein (NCp7) in vitro, as monitored by the zinc-specific fluorescent probe N-(6-methoxy-8-quinoyl)-p-toluenesulfonamide (TSQ). Structurally similar disulfide benzamides that do not inhibit HIV-1 in culture do not eject zinc, nor do analogs of the antiviral compounds with the disulfide replaced with a methylene sulfide. The kinetics of NCp7 zinc ejection by disulfide benzamides were found to be nonsaturable and biexponential, with the rate of ejection from the C-terminal zinc finger 7-fold faster than that from the N-terminal. The antiviral compounds were found to inhibit the zinc-dependent binding of NCp7 to HIV psi RNA, as studied by gel-shift assays, and the data correlated well with the zinc ejection data. Anti-HIV disulfide benzamides specifically eject NCp7 zinc and abolish the protein's ability to bind psi RNA in vitro, providing evidence for a possible antiretroviral mechanism of action of these compounds. Congeners of this class are under advanced preclinical evaluation as a potential chemotherapy for acquired immunodeficiency syndrome. Images Fig. 7 PMID:8577770

  1. Structural basis for germ-line gene usage of a potent class of antibodies targeting the CD4-binding site of HIV-1 gp120.

    PubMed

    West, Anthony P; Diskin, Ron; Nussenzweig, Michel C; Bjorkman, Pamela J

    2012-07-24

    A large number of anti-HIV-1 antibodies targeting the CD4-binding site (CD4bs) on the envelope glycoprotein gp120 have recently been reported. These antibodies, typified by VRC01, are remarkable for both their breadth and their potency. Crystal structures have revealed a common mode of binding for several of these antibodies; however, the precise relationship among CD4bs antibodies remains to be defined. Here we analyze existing structural and sequence data, propose a set of signature features for potent VRC01-like (PVL) antibodies, and verify the importance of these features by mutagenesis. The signature features explain why PVL antibodies derive from a single germ-line human V(H) gene segment and why certain gp120 sequences are associated with antibody resistance. Our results bear on vaccine development and structure-based design to improve the potency and breadth of anti-CD4bs antibodies.

  2. Is Metformin-Induced Vitamin B12 Deficiency Responsible for Cognitive Decline in Type 2 Diabetes?

    PubMed Central

    Khattar, Deepti; Khaliq, Farah; Vaney, Neelam; Madhu, S. V.

    2016-01-01

    Introduction: Diabetes mellitus has its deleterious effects on various aspects of cognition such as memory function, executive function, and information-processing speed. The present study aims to assess cognition in diabetes patients and also tries to find its association with Vitamin B12 deficiency induced by metformin. Materials and Methods: Thirty diabetics taking metformin and thirty nondiabetic controls were enrolled. Event-related potentials (ERPs) and serum Vitamin B12 levels were evaluated in them. Results: Vitamin B12 levels were found to be deficient, and latencies of waves P200 and P300 were prolonged in the diabetics as compared to the controls. The dose and duration of metformin had no association with the ERPs. Conclusions: Although the Vitamin B12 levels were deficient in diabetics on metformin, this is not the reason behind the cognitive impairment found in them. PMID:27570337

  3. Effect of vitamin B12 deficiency on neurodevelopment in infants: current knowledge and possible mechanisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Severe vitamin B12 deficiency produces a cluster of neurological symptoms in infants, including irritability, failure to thrive, apathy, anorexia, and developmental regression, which respond remarkably rapidly to supplementation. The underlying mechanisms may involve delayed myelination or demyelina...

  4. DOUBLE MAGAZINE LOCATED BETWEEN MAGAZINES B12 & B13. VIEW FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DOUBLE MAGAZINE LOCATED BETWEEN MAGAZINES B-12 & B-13. VIEW FROM LEFT SIDE. - Naval Magazine Lualualei, Waikele Branch, Tunnel Magazine Type, Waikakalaua & Kipapa Gulches, Pearl City, Honolulu County, HI

  5. DOUBLE MAGAZINE LOCATED BETWEEN MAGAZINES B12 & B13. VIEW FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DOUBLE MAGAZINE LOCATED BETWEEN MAGAZINES B-12 & B-13. VIEW FROM RIGHT SIDE SHOWING GUARD TOWER S83 ON RIDGE BEHIND MAGAZINE. - Naval Magazine Lualualei, Waikele Branch, Tunnel Magazine Type, Waikakalaua & Kipapa Gulches, Pearl City, Honolulu County, HI

  6. DOUBLE MAGAZINE LOCATED BETWEEN MAGAZINES B12 & B13. FRONT ELEVATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DOUBLE MAGAZINE LOCATED BETWEEN MAGAZINES B-12 & B-13. FRONT ELEVATION WITH RANGE POLE. - Naval Magazine Lualualei, Waikele Branch, Tunnel Magazine Type, Waikakalaua & Kipapa Gulches, Pearl City, Honolulu County, HI

  7. Magnetic properties of Ho1- x Lu x B12 solid solutions

    NASA Astrophysics Data System (ADS)

    Gabáni, S.; Gaz̆o, E.; Pristás̆, G.; Takác̆ová, I.; Flachbart, K.; Shitsevalova, N.; Siemensmeyer, K.; Sluchanko, N.

    2013-05-01

    Magnetic properties of the geometrically frustrated antiferromagnet HoB12 (with T N = 7.4 K) modified by substitution of magnetic Ho atoms through non-magnetic Lu ones are presented and discussed. In this case, in Ho1- x Lu x B12 solid solutions, both chemical pressure resulting from different Lu3+ and Ho3+ radii and magnetic dilution take place with increasing Lu content ( x) that change properties of the system. The received results show strong indication for the existence of a quantum critical point near x = 0.9, which separates the region of magnetic order (starting with HoB12 for x = 0) and the nonmagnetic region (ending with superconducting LuB12 for x = 1).

  8. How Nature Builds the Pigments of Life: The Conquest of Vitamin B12

    NASA Astrophysics Data System (ADS)

    Battersby, Alan R.

    1994-06-01

    In part because humans cannot synthesize vitamin B12 and must obtain it from organisms that produce it and because B12 deficiency leads to pernicious anemia, it has been important to understand how microorganisms build this quite complex substance. As shown here, an interdisciplinary attack was needed, which combined the strengths of genetics, molecular biology, enzymology, chemistry, and spectroscopy. This allowed the step-by-step synthetic pathway of B12 to be elucidated, and this approach has acted as a model for future research on the synthesis of substances in living organisms. One practical outcome of such an approach has been the improved availability of B12 for animal feedstuffs and human health.

  9. Involuntary movements after correction of vitamin B12 deficiency: a video-case report.

    PubMed

    Zanus, Caterina; Alberini, Elena; Costa, Paola; Colonna, Franco; Zennaro, Floriana; Carrozzi, Marco

    2012-06-01

    Involuntary movements can appear before and after initiation of vitamin B12 treatment. The pathogenesis of involuntary movements in vitamin B12 deficiency and their relationship with cobalamin injection remain unclear due to a lack of video-EEG documentation making the electroclinical correlation difficult to ascertain. Here, we report video-EEG and neuroimaging findings of an 11-month-old girl with vitamin B12 deficiency, who acutely developed involuntary movements a few days after initiation of vitamin B12 treatment with normal vitamin plasmatic levels. Abnormal movements were a combination of tremor and myoclonus involving the face, mouth, and left arm, which disappeared after discontinuation of therapy. [Published with video sequences].

  10. A new role for glutathione: protection of vitamin B12 from depletion by xenobiotics.

    PubMed

    Watson, William P; Munter, Tony; Golding, Bernard T

    2004-12-01

    NADPH in microsomes reduces the hydroxocob(III)alamin form of vitamin B12 to cob(II)alamin and the supernucleophilic cob(I)alamin, which are both highly reactive toward xenobiotic epoxides formed by mammalian metabolism of dienes such as the industrially important chemicals chloroprene and 1,3-butadiene. With styrene, the metabolically formed styrene oxide is reactive toward cob(I)alamin but not cob(II)alamin. Such reactions in humans could lead to vitamin B12 deficiency, which is implicated in pernicious anemia, cancer, and degenerative diseases. However, glutathione inhibits the reduction of hydroxocob(III)alamin by formation of the 1:1 complex glutathionylcobalamin. This blocks reactions of the cobalamins with metabolically formed epoxides. The interaction between glutathione and vitamin B12 could protect against diseases related to vitamin B12 depletion.

  11. Metabolic network rewiring of propionate flux compensates vitamin B12 deficiency in C. elegans.

    PubMed

    Watson, Emma; Olin-Sandoval, Viridiana; Hoy, Michael J; Li, Chi-Hua; Louisse, Timo; Yao, Victoria; Mori, Akihiro; Holdorf, Amy D; Troyanskaya, Olga G; Ralser, Markus; Walhout, Albertha Jm

    2016-07-06

    Metabolic network rewiring is the rerouting of metabolism through the use of alternate enzymes to adjust pathway flux and accomplish specific anabolic or catabolic objectives. Here, we report the first characterization of two parallel pathways for the breakdown of the short chain fatty acid propionate in Caenorhabditis elegans. Using genetic interaction mapping, gene co-expression analysis, pathway intermediate quantification and carbon tracing, we uncover a vitamin B12-independent propionate breakdown shunt that is transcriptionally activated on vitamin B12 deficient diets, or under genetic conditions mimicking the human diseases propionic- and methylmalonic acidemia, in which the canonical B12-dependent propionate breakdown pathway is blocked. Our study presents the first example of transcriptional vitamin-directed metabolic network rewiring to promote survival under vitamin deficiency. The ability to reroute propionate breakdown according to B12 availability may provide C. elegans with metabolic plasticity and thus a selective advantage on different diets in the wild.

  12. [Folate metabolism--epigenetic role of choline and vitamin B12 during pregnancy].

    PubMed

    Drews, Krzysztof

    2015-12-01

    Adequate choline intake during pregnancy is essential for proper fetal development. Nowadays studies suggest that even in high income countries regular pregnant women diet does not provide the satisfactory amount of choline. Choline demand during pregnancy is high and it seems to exceed present choline intake recommendations. Moreover lactation period also demands choline supplementation because of its high concentration in female milk. Numerous studies on animal model proved correlation between choline supplementation during pregnancy and proper fetal cognitive function development. Despite increased synthesis in maternal liver during pregnancy choline demand is much higher than common dietary uptake. Nowadays studies as to the nutritional recommendations during pregnancy concern also vitamin B12 supplementation. Vitamin B12 deficiency may be an important risk factor of neural tube defects development. Presented article contains a review of data on proper choline and vitamin B12 uptake during pregnancy and lactation and potential results of choline and vitamin B12 poor maternal status.

  13. Vitamin B12 modulates the transcriptome of the skin microbiota in acne pathogenesis.

    PubMed

    Kang, Dezhi; Shi, Baochen; Erfe, Marie C; Craft, Noah; Li, Huiying

    2015-06-24

    Various diseases have been linked to the human microbiota, but the underlying molecular mechanisms of the microbiota in disease pathogenesis are often poorly understood. Using acne as a disease model, we aimed to understand the molecular response of the skin microbiota to host metabolite signaling in disease pathogenesis. Metatranscriptomic analysis revealed that the transcriptional profiles of the skin microbiota separated acne patients from healthy individuals. The vitamin B12 biosynthesis pathway in the skin bacterium Propionibacterium acnes was significantly down-regulated in acne patients. We hypothesized that host vitamin B12 modulates the activities of the skin microbiota and contributes to acne pathogenesis. To test this hypothesis, we analyzed the skin microbiota in healthy subjects supplemented with vitamin B12. We found that the supplementation repressed the expression of vitamin B12 biosynthesis genes in P. acnes and altered the transcriptome of the skin microbiota. One of the 10 subjects studied developed acne 1 week after vitamin B12 supplementation. To further understand the molecular mechanism, we revealed that vitamin B12 supplementation in P. acnes cultures promoted the production of porphyrins, which have been shown to induce inflammation in acne. Our findings suggest a new bacterial pathogenesis pathway in acne and provide one molecular explanation for the long-standing clinical observation that vitamin B12 supplementation leads to acne development in a subset of individuals. Our study discovered that vitamin B12, an essential nutrient in humans, modulates the transcriptional activities of skin bacteria, and provided evidence that metabolite-mediated interactions between the host and the skin microbiota play essential roles in disease development.

  14. Combined indicator of vitamin B12 status: modification for missing biomarkers and folate status, and recommendations for revised cut-points

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: We propose a novel approach to diagnose B12 status by combining four blood markers: total B12 (B12), holo-transcobalamin (holoTC), methylmalonic acid (MMA) and total homocysteine (tHcy). Combined B12 status is expressed as cB12=log10[(holoTC•B12)/(MMA•Hcy)]–(reference, age function). Her...

  15. Combined indicator of vitamin B 12 status: modification for missing biomarkers and folate status and recommendations for revised cut-points

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: A novel approach to determine vitamin B 12 status is to combine four blood markers: total B 12 (B 12 ), holotranscobalamin (holoTC), methylmalonic acid (MMA) and total homocysteine (tHcy). This combined indicator of B 12 status is expressed as cB 12 = log 10 [(holoTC · B 12 )/ (MMA · Hcy...

  16. Associations between Vitamin B-12 Status and Oxidative Stress and Inflammation in Diabetic Vegetarians and Omnivores.

    PubMed

    Lee, Yau-Jiunn; Wang, Ming-Yang; Lin, Mon-Chiou; Lin, Ping-Ting

    2016-02-26

    Diabetes is considered an oxidative stress and a chronic inflammatory disease. The purpose of this study was to investigate the correlations between vitamin B-12 status and oxidative stress and inflammation in diabetic vegetarians and omnivores. We enrolled 154 patients with type 2 diabetes (54 vegetarians and 100 omnivores). Levels of fasting glucose, glycohemoglobin (HbA1c), lipid profiles, oxidative stress, antioxidant enzymes activity, and inflammatory makers were measured. Diabetic vegetarians with higher levels of vitamin B-12 (>250 pmol/L) had significantly lower levels of fasting glucose, HbA1c and higher antioxidant enzyme activity (catalase) than those with lower levels of vitamin B-12 (≤ 250 pmol/L). A significant association was found between vitamin B-12 status and fasting glucose (r = -0.17, p = 0.03), HbA1c (r = -0.33, p = 0.02), oxidative stress (oxidized low density lipoprotein-cholesterol, r = -0.19, p = 0.03), and antioxidant enzyme activity (catalase, r = 0.28, p = 0.01) in the diabetic vegetarians; vitamin B-12 status was significantly correlated with inflammatory markers (interleukin-6, r = -0.33, p < 0.01) in diabetic omnivores. As a result, we suggest that it is necessary to monitor the levels of vitamin B-12 in patients with diabetes, particularly those adhering to a vegetarian diet.

  17. Vitamin B12: one carbon metabolism, fetal growth and programming for chronic disease.

    PubMed

    Rush, E C; Katre, P; Yajnik, C S

    2014-01-01

    This review brings together human and animal studies and reviews that examine the possible role of maternal vitamin B12 (B12) on fetal growth and its programming for susceptibility to chronic disease. A selective literature review was undertaken to identify studies and reviews that investigate these issues, particularly in the context of a vegetarian diet that may be low in B12 and protein and high in carbohydrate. Evidence is accumulating that maternal B12 status influences fetal growth and development. Low maternal vitamin B12 status and protein intake are associated with increased risk of neural tube defect, low lean mass and excess adiposity, increased insulin resistance, impaired neurodevelopment and altered risk of cancer in the offspring. Vitamin B12 is a key nutrient associated with one carbon metabolic pathways related to substrate metabolism, synthesis and stability of nucleic acids and methylation of DNA which regulates gene expression. Understanding of factors regulating maternal-fetal one carbon metabolism and its role in fetal programming of non communicable diseases could help design effective interventions, starting with maternal nutrition before conception.

  18. Cyanobacteria and Eukaryotic Algae Use Different Chemical Variants of Vitamin B12

    PubMed Central

    Helliwell, Katherine Emma; Lawrence, Andrew David; Holzer, Andre; Kudahl, Ulrich Johan; Sasso, Severin; Kräutler, Bernhard; Scanlan, David John; Warren, Martin James; Smith, Alison Gail

    2016-01-01

    Summary Eukaryotic microalgae and prokaryotic cyanobacteria are the major components of the phytoplankton. Determining factors that govern growth of these primary producers, and how they interact, is therefore essential to understanding aquatic ecosystem productivity. Over half of microalgal species representing marine and freshwater habitats require for growth the corrinoid cofactor B12, which is synthesized de novo only by certain prokaryotes, including the majority of cyanobacteria. There are several chemical variants of B12, which are not necessarily functionally interchangeable. Cobalamin, the form bioavailable to humans, has as its lower axial ligand 5,6-dimethylbenzimidazole (DMB). Here, we show that the abundant marine cyanobacterium Synechococcus synthesizes only pseudocobalamin, in which the lower axial ligand is adenine. Moreover, bioinformatic searches of over 100 sequenced cyanobacterial genomes for B12 biosynthesis genes, including those involved in nucleotide loop assembly, suggest this is the form synthesized by cyanobacteria more broadly. We further demonstrate that pseudocobalamin is several orders of magnitude less bioavailable than cobalamin to several B12-dependent microalgae representing diverse lineages. This indicates that the two major phytoplankton groups use a different B12 currency. However, in an intriguing twist, some microalgal species can use pseudocobalamin if DMB is provided, suggesting that they are able to remodel the cofactor, whereas Synechococcus cannot. This species-specific attribute implicates algal remodelers as novel and keystone players of the B12 cycle, transforming our perception of the dynamics and complexity of the flux of this nutrient in aquatic ecosystems. PMID:27040778

  19. Potential cobalt limitation of vitamin B12 synthesis in the North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Panzeca, C.; Beck, A. J.; Leblanc, K.; Taylor, G. T.; Hutchins, D. A.; SañUdo-Wilhelmy, S. A.

    2008-06-01

    While recent studies have confirmed the ecological importance of vitamin B12, it is unclear whether the production of this vitamin could be limited by dissolved Co, a trace metal required for B12 biosynthesis, but found at only subnanomolar concentrations in the open ocean. Herein, we demonstrate that the spatial distribution of dissolved B12 (range: 0.13-5 pmol L-1) in the North Atlantic Ocean follows the abundance of total dissolved Co (range: 15-81 pmol L-1). Similar patterns were observed for bacterial productivity (range: 20-103 pmol 3H leucine L-1 hr-1) and algal biomass (range: 0.4-3.9 μg L-1). In contrast, vitamin B1 concentrations (range: 0.7-30 pM) were decoupled from both Co and B12 concentrations. Cobalt amendment experiments carried out in low-dissolved Co waters (˜20 pmol L-1) enhanced B12 production two-fold over unamended controls. This study provides evidence that B12 synthesis could be limited by the availability of Co in some regions of the world ocean.

  20. Microbial production of vitamin B12: a review and future perspectives.

    PubMed

    Fang, Huan; Kang, Jie; Zhang, Dawei

    2017-01-30

    Vitamin B12 is an essential vitamin that is widely used in medical and food industries. Vitamin B12 biosynthesis is confined to few bacteria and archaea, and as such its production relies on microbial fermentation. Rational strain engineering is dependent on efficient genetic tools and a detailed knowledge of metabolic pathways, regulation of which can be applied to improve product yield. Recent advances in synthetic biology and metabolic engineering have been used to efficiently construct many microbial chemical factories. Many published reviews have probed the vitamin B12 biosynthetic pathway. To maximize the potential of microbes for vitamin B12 production, new strategies and tools are required. In this review, we provide a comprehensive understanding of advances in the microbial production of vitamin B12, with a particular focus on establishing a heterologous host for the vitamin B12 production, as well as on strategies and tools that have been applied to increase microbial cobalamin production. Several worthy strategies employed for other products are also included.

  1. Folate and vitamin B12: function and importance in cognitive development.

    PubMed

    Troen, Aron M

    2012-01-01

    The importance of the B vitamins folate and vitamin B12 for healthy neurological development and function is unquestioned. Folate and vitamin B12 are required for biological methylation and DNA synthesis. Vitamin B12 also participates in the mitochondrial catabolism of odd-chain fatty acids and some amino acids. Inborn errors of their metabolism and severe nutritional deficiencies cause serious neurological and hematological pathology. Poor folate and vitamin B12 status short of clinical deficiency is associated with increased risk of cognitive impairment, depression, Alzheimer's disease and stroke among older adults and increased risk of neural tube defects among children born to mothers with low folate status. Folate supplementation and food fortification are known to reduce incident neural tube defects, and B vitamin supplementation may have cognitive benefit in older adults. Less is known about folate and vitamin B12 requirements for optimal brain development and long-term cognitive health in newborns, children and adolescents. While increasing suboptimal nutritional status has observed benefits, the long-term effects of high folate intake are uncertain. Several observations of unfavorable health indicators in children and adults exposed to high folic acid intake make it imperative to achieve a more precise definition of folate and B12 requirements for brain development and function.

  2. Serum homocysteine, vitamin B12, folic acid levels and methylenetetrahydrofolate reductase (MTHFR) gene polymorphism in vitiligo.

    PubMed

    Yasar, Ali; Gunduz, Kamer; Onur, Ece; Calkan, Mehmet

    2012-01-01

    The aim of this study was to determine serum vitamin B12, folic acid and homocysteine (Hcy) levels as well as MTHFR (C677, A1298C) gene polymorphisms in patients with vitiligo, and to compare the results with healthy controls. Forty patients with vitiligo and 40 age and sex matched healthy subjects were studied. Serum vitamin B12 and folate levels were determined by enzyme-linked immunosorbent assay. Plasma Hcy levels and MTHFR polymorphisms were determined by chemiluminescence and real time PCR methods, respectively. Mean serum vitamin B12 and Hcy levels were not significantly different while folic acid levels were significantly lower in the control group. There was no significant relationship between disease activity and vitamin B12, folic acid and homocystein levels. No significant difference in C677T gene polymorphism was detected. Heterozygote A1298C gene polymorphism in the patient group was statistically higher than the control group. There was no significant relationship between MTHFR gene polymorphisms and vitamin B12, folic acid and homocysteine levels. In conclusion, vitamin B12, folate and Hcy levels are not altered in vitiligo and MTHFR gene mutations (C677T and A1298C) do not seem to create susceptibility for vitiligo.

  3. Vitamin B12 in neurology and ageing; clinical and genetic aspects.

    PubMed

    McCaddon, Andrew

    2013-05-01

    The classic neurological and psychiatric features associated with vitamin B12 deficiency have been well described and are the subject of many excellent review articles. The advent of sensitive diagnostic tests, including homocysteine and methylmalonic acid assays, has revealed a surprisingly high prevalence of a more subtle 'subclinical' form of B12 deficiency, particularly within the elderly. This is often associated with cognitive impairment and dementia, including Alzheimer's disease. Metabolic evidence of B12 deficiency is also reported in association with other neurodegenerative disorders including vascular dementia, Parkinson's disease and multiple sclerosis. These conditions are all associated with chronic neuro-inflammation and oxidative stress. It is possible that these clinical associations reflect compromised vitamin B12 metabolism due to such stress. Physicians are also increasingly aware of considerable inter-individual variation in the clinical response to B12 replacement therapy. Further research is needed to determine to what extent this is attributable to genetic determinants of vitamin B12 absorption, distribution and cellular uptake.

  4. High doses of oral folate and sublingual vitamin B12 in dialysis patients with hyperhomocysteinemia

    PubMed Central

    Naseri, Mitra; Sarvari, Gholam-Reza; Esmaeeli, Mohammad; Azarfar, Anoush; Rasouli, Zahra; Moeenolroayaa, Giti; Jahanshahi, Shohre; Farhadi, Simin; Heydari, Zohreh; Sagheb-Taghipoor, Narges

    2016-01-01

    Introduction: Folic acid and vitamin B12, alone or in combination have been used to reduce homocysteine (Hcy) levels in dialysis patients. Objectives: We aimed to assess the efficacy of high doses of oral folate and vitamin B12 in reducing plasma Hcy levels after a 12-week treatment. Patients and Methods: Thirty-two dialysis patients aged 10-324 months screened for hyperhomocysteinuria. Then cases with hyperhomocysteinemia received oral folate 10 mg/day with sublingual methylcobalamin 1 mg/day for 12 weeks. In pre- and post-intervention phases plasma Hcy concentration, serum folate, and vitamin B12 levels were measured. Changes in plasma Hcy, serum folate, and vitamin B12 concentrations were analyzed by paired t tests, and P values < 0.05 were considered significant. Results: Eighteen (56.2%) patients had hyperhomocysteinuria. Vitamin B12 and folate levels were normal or high in all cases. Two patients were lost due to transplant or irregular drugs consumption. Plasma Hcy levels were reduced in all, and reached normal values in 50%. A statistically significant differences between first Hcy levels with levels after intervention was found (95% CI, 5.1–8.9, P = 0.0001). Conclusion: Oral folate 10 mg/day in combination with sublingual vitamin B12, 1 mg/day can be considered as a favorable treatment for hyperhomocysteinemia in dialysis patients. PMID:27689109

  5. [Vitamin B12 supplementation and milk production on farms with 'chronic wasting' cattle].

    PubMed

    Weber, M F; Verhoeff, J; Holzhauer, M; Bartels, C J; van Wuijckhuise, L; Vellema, P

    2001-03-15

    From early 1999 onwards, cattle health problems accompanied by chronic wasting of unknown aetiology were reported on a number of dairy farms. An association between these health problems and the compulsory use of gE-negative marker vaccines against bovine herpesvirus 1 was presumed by farmers. On one dairy farm an increased milk production of 50% was reported within a few days after parenteral vitamin B12 treatment. Therefore, the current study was designed to determine the effect of parenteral vitamin B12 treatment on the milk production of dairy herds with wasting cattle. A randomized blind trial was performed in five problem herds and two control herds. On each farm five lactating cows were injected intramuscularly with 20 mg vitamin B12 and paired with five untreated lactating cows. The milk production of treated and untreated animals was measured for 19 days following treatment and compared to pre-treatment production. No effect of vitamin B12 treatment on milk production was established on either problem farms or control farms. Neither was a difference detected in the response to vitamin B12 treatment between problem herds and control herds. In a second experiment, parenteral vitamin B12 treatment was applied in three problem herds by local veterinary practitioners. The results of this experiment were in line with the results of the first experiment.

  6. Competitive chemiluminescent enzyme immunoassay for vitamin B12 analysis in human milk.

    PubMed

    Hampel, Daniela; Shahab-Ferdows, Setareh; Domek, Joseph M; Siddiqua, Towfida; Raqib, Rubhana; Allen, Lindsay H

    2014-06-15

    Recent discoveries of matrix interferences by haptocorrin (HC) in human milk and serum show that past analyses of vitamin B12 in samples with high HC content might have been inaccurate (Lildballe et al., 2009; Carmel & Agrawal, 2012). We evaluated two competitive enzyme-binding immunoassays for serum/plasma (IMMULITE and SimulTRAC-SNB) for B12 analysis in human milk. B12-recovery rates (United States Environmental Protection Agency, 2007) were determined to be 78.9 ± 9.1% with IMMULITE and 225 ± 108% (range 116-553%) using SimulTRAC-SNB, most likely due to the presence of excess HC. HC-interferences were not observed with the IMMULITE assay, rendering previously reported mandatory HC-removal (Lildballe et al., 2009) unnecessary. Linearity continued at low B12-concentrations (24-193 pM; r(2)>0.985). Milk B12 concentrations from Bangladeshi women (72-959 pM) were significantly lower than those from California (154-933 pM; p<0.0001) showing IMMULITE's robustness against the complex milk matrix and its ability to measure low milk B12 concentrations.

  7. High prevalence of suboptimal vitamin B12 status in young adult women of South Asian and European ethnicity.

    PubMed

    Quay, Teo A W; Schroder, Theresa H; Jeruszka-Bielak, Marta; Li, Wangyang; Devlin, Angela M; Barr, Susan I; Lamers, Yvonne

    2015-12-01

    Suboptimal vitamin B12 (B12) status has been associated with an increased risk of congenital anomalies, preterm birth, and childhood insulin resistance. South Asians - Canada's largest minority group - and women of reproductive age are vulnerable to B12 deficiency. This study aimed to assess the prevalence of and factors associated with B12 deficiency and suboptimal B12 status in a convenience sample of young adult women of South Asian and European descent in Metro Vancouver. We measured serum B12, holotranscobalamin, plasma methylmalonic acid, red blood cell and plasma folate, and hematologic parameters in 206 nonpregnant, healthy women aged 19-35 years. Categorization for B12 status adhered to serum B12 cutoffs for deficiency (<148 pmol/L) and suboptimal B12 status (148-220 pmol/L). We collected demographic, lifestyle, and dietary intake data and conducted genotyping for common genetic variants linked to B-vitamin metabolism. The prevalence of deficiency and suboptimal B12 status were 14% and 20%, respectively. Serum vitamin B12 concentrations were negatively associated with oral contraceptive use and first-generation immigrant status, and positively with dietary B12 intake and B12 supplement use. The prevalence of B12 inadequacy in this sample of highly educated women is higher than in the general Canadian population. In light of maternal and fetal health risks associated with B12 inadequacy in early-pregnancy, practitioners should consider monitoring B12 status before and during early pregnancy, especially in immigrants and women with low dietary B12 intakes including non-users of vitamin supplements.

  8. Genetic variation in vitamin B-12 content of bovine milk and its association with SNP along the bovine genome.

    PubMed

    Rutten, Marc J M; Bouwman, Aniek C; Sprong, R Corinne; van Arendonk, Johan A M; Visker, Marleen H P W

    2013-01-01

    Vitamin B-12 (also called cobalamin) is essential for human health and current intake levels of vitamin B-12 are considered to be too low. Natural enrichment of the vitamin B-12 content in milk, an important dietary source of vitamin B-12, may help to increase vitamin B-12 intake. Natural enrichment of the milk vitamin B-12 content could be achieved through genetic selection, provided there is genetic variation between cows with respect to the vitamin B-12 content in their milk. A substantial amount of genetic variation in vitamin B-12 content was detected among raw milk samples of 544 first-lactation Dutch Holstein Friesian cows. The presence of genetic variation between animals in vitamin B-12 content in milk indicates that the genotype of the cow affects the amount of vitamin B-12 that ends up in her milk and, consequently, that the average milk vitamin B-12 content of the cow population can be increased by genetic selection. A genome-wide association study revealed significant association between 68 SNP and vitamin B-12 content in raw milk of 487 first-lactation Dutch Holstein Friesian cows. This knowledge facilitates genetic selection for milk vitamin B-12 content. It also contributes to the understanding of the biological mechanism responsible for the observed genetic variation in vitamin B-12 content in milk. None of the 68 significantly associated SNP were in or near known candidate genes involved in transport of vitamin B-12 through the gastrointestinal tract, uptake by ileum epithelial cells, export from ileal cells, transport through the blood, uptake from the blood, intracellular processing, or reabsorption by the kidneys. Probably, associations relate to genes involved in alternative pathways of well-studied processes or to genes involved in less well-studied processes such as ruminal production of vitamin B-12 or secretion of vitamin B-12 by the mammary gland.

  9. Genetic Variation in Vitamin B-12 Content of Bovine Milk and Its Association with SNP along the Bovine Genome

    PubMed Central

    Rutten, Marc J. M.; Bouwman, Aniek C.; Sprong, R. Corinne; van Arendonk, Johan A. M.; Visker, Marleen H. P. W.

    2013-01-01

    Vitamin B-12 (also called cobalamin) is essential for human health and current intake levels of vitamin B-12 are considered to be too low. Natural enrichment of the vitamin B-12 content in milk, an important dietary source of vitamin B-12, may help to increase vitamin B-12 intake. Natural enrichment of the milk vitamin B-12 content could be achieved through genetic selection, provided there is genetic variation between cows with respect to the vitamin B-12 content in their milk. A substantial amount of genetic variation in vitamin B-12 content was detected among raw milk samples of 544 first-lactation Dutch Holstein Friesian cows. The presence of genetic variation between animals in vitamin B-12 content in milk indicates that the genotype of the cow affects the amount of vitamin B-12 that ends up in her milk and, consequently, that the average milk vitamin B-12 content of the cow population can be increased by genetic selection. A genome-wide association study revealed significant association between 68 SNP and vitamin B-12 content in raw milk of 487 first-lactation Dutch Holstein Friesian cows. This knowledge facilitates genetic selection for milk vitamin B-12 content. It also contributes to the understanding of the biological mechanism responsible for the observed genetic variation in vitamin B-12 content in milk. None of the 68 significantly associated SNP were in or near known candidate genes involved in transport of vitamin B-12 through the gastrointestinal tract, uptake by ileum epithelial cells, export from ileal cells, transport through the blood, uptake from the blood, intracellular processing, or reabsorption by the kidneys. Probably, associations relate to genes involved in alternative pathways of well-studied processes or to genes involved in less well-studied processes such as ruminal production of vitamin B-12 or secretion of vitamin B-12 by the mammary gland. PMID:23626813

  10. Dual isotope Schilling test for measuring absorption of food-bound and free vitamin B12 simultaneously

    SciTech Connect

    Doscherholmen, A.; Silvis, S.; McMahon, J.

    1983-10-01

    A prototype food-bound vitamin B12 (food-B12) absorption test has been developed in which /sup 57/Co-B12 was incorporated in vitro into egg yolk (yolk-B12) and served to volunteers in 50-g cooked portions together with toast and coffee for breakfast. Six hours later, 1 mg nonlabeled B12 was given intramuscularly and 24-hour urine was collected for radioactivity measurement. In separate tests, the absorption of yolk-B12 and crystalline /sup 57/Co-B12 was equally poor in patients with pernicious anemia. However, in patients with simple gastric achlorhydria and those who had undergone gastric surgery, the assimilation of yolk-B12 was impaired greatly, whereas the absorption of crystalline radio-B12 was normal. Egg yolk labeled with /sup 58/Co-B12 was administered together with crystalline /sup 57/Co-B12 in a dual isotope test with results similar to those obtained when the tests were prepared separately. This yolk-/sup 58/Co-B12 test with its ability to detect malabsorption of food-B12 may be considered as an addition to the first part of the Schilling test.

  11. Transcobalamin derived from bovine milk stimulates apical uptake of vitamin B12 into human intestinal epithelial cells.

    PubMed

    Hine, Brad; Boggs, Irina; Green, Ralph; Miller, Joshua W; Hovey, Russell C; Humphrey, Rex; Wheeler, Thomas T

    2014-11-01

    Intestinal uptake of vitamin B12 (hereafter B12) is impaired in a significant proportion of the human population. This impairment is due to inherited or acquired defects in the expression or function of proteins involved in the binding of diet-derived B12 and its uptake into intestinal cells. Bovine milk is an abundant source of bioavailable B12 wherein it is complexed with transcobalamin. In humans, transcobalamin functions primarily as a circulatory protein, which binds B12 following its absorption and delivers it to peripheral tissues via its cognate receptor, CD320. In the current study, the transcobalamin-B12 complex was purified from cows' milk and its ability to stimulate uptake of B12 into cultured bovine, mouse and human cell lines was assessed. Bovine milk-derived transcobalamin-B12 complex was absorbed by all cell types tested, suggesting that the uptake mechanism is conserved across species. Furthermore, the complex stimulated the uptake of B12 via the apical surface of differentiated Caco-2 human intestinal epithelial cells. These findings suggest the presence of an alternative transcobalamin-mediated uptake pathway for B12 in the human intestine other than that mediated by the gastric glycoprotein, intrinsic factor. Our findings highlight the potential for transcobalamin-B12 complex derived from bovine milk to be used as a natural bioavailable alternative to orally administered free B12 to overcome B12 malabsorption.

  12. Oral vitamin B12 supplementation reduces plasma total homocysteine concentration in women in India.

    PubMed

    Yajnik, Chittaranjan S; Lubree, Himangi G; Thuse, Nileema V; Ramdas, Lalita V; Deshpande, Swapna S; Deshpande, Vaishali U; Deshpande, Jyoti A; Uradey, Bhagyashree S; Ganpule, Anjali A; Naik, Sadanand S; Joshi, Niranjan P; Farrant, Hannah; Refsum, Helga

    2007-01-01

    People in India have a high prevalence of low vitamin B12 status and high plasma total homocysteine (tHcy) concentrations. In a proof of principle trial, we studied the effect of oral vitamin B12 (500 microg) and/or 100 g cooked green leafy vegetables (GLV) every alternate day in a 2x2 factorial design over a 6-week period. Forty-two non-pregnant vegetarian women (age 20-50 years) were randomly allocated to four study groups. Clinical measurements were made at the beginning and at the end of the study, and blood samples were collected before, and 2 and 6 weeks after commencement of intervention. Forty women completed the trial. Twenty-six women had low vitamin B12 status (<150 pmol/L) and 24 had hyperhomocysteinemia (>15 micromol/L). GLV supplementation did not alter plasma folate or tHcy. Vitamin B12 supplementation increased plasma vitamin B12 concentration (125 to 215 pmol/L, p <0.05) and reduced tHcy concentration (18.0 to 13.0 micromol/L, p <0.05) within first 2 weeks, both of which remained stable for the next 4 weeks. Plasma vitamin B12 and tHcy concentrations did not change in those who did not receive vitamin B12, and there was no change in plasma folate concentration in any of the groups. Blood haemoglobin concentration increased marginally within first two weeks in those women who received vitamin B12 (by 3 g/L, p <0.05) and the number of women with macrocytosis decreased from 2 to zero. There was no change in vibration sensory threshold during the period of the study. High-dose per oral vitamin B12 supplementation significantly reduced plasma tHcy within 2 weeks but did not achieve normal plasma tHcy concentration even after 6 weeks. People in India have a high prevalence of low vitamin B12 status and high plasma total homocysteine (tHcy) concentrations.

  13. Defense-in-depth by mucosally administered anti-HIV dimeric IgA2 and systemic IgG1 mAbs: Complete protection of rhesus monkeys from mucosal SHIV challenge

    PubMed Central

    Sholukh, Anton M.; Watkins, Jennifer D.; Vyas, Hemant K.; Gupta, Sandeep; Lakhashe, Samir K.; Thorat, Swati; Zhou, Mingkui; Hemashettar, Girish; Bachler, Barbara C.; Forthal, Donald N.; Villinger, Francois; Sattentau, Quentin J.; Weiss, Robin A.; Agatic, Gloria; Corti, Davide; Lanzavecchia, Antonio; Heeney, Jonathan L.; Ruprecht, Ruth M.

    2015-01-01

    Although IgA is the most abundantly produced immunoglobulin in humans, its role in preventing HIV-1 acquisition, which occurs mostly via mucosal routes, remains unclear. In our passive mucosal immunizations of rhesus macaques (RMs), the anti-HIV-1 neutralizing monoclonal antibody (nmAb) HGN194, given either as dimeric IgA1 (dIgA1) or dIgA2 intrarectally (i.r.), protected 83% or 17% of the RMs against i.r. simian-human immunodeficiency virus (SHIV) challenge, respectively. Data from the RV144 trial implied that vaccine-induced plasma IgA counteracted the protective effector mechanisms of IgG1 with the same epitope specificity. We thus hypothesized that mucosal dIgA2 might diminish the protection provided by IgG1 mAbs targeting the same epitope. To test our hypothesis, we administered HGN194 IgG1 intravenously (i.v.) either alone or combined with i.r. HGN194 dIgA2. We enrolled SHIV-exposed, persistently aviremic RMs protected by previously administered nmAbs; RM anti-human IgG responses were undetectable. However, low-level SIV Gag-specific proliferative T-cell responses were found. These animals resemble HIV-exposed, uninfected humans, in which local and systemic cellular immune responses have been observed. HGN194 IgG1 and dIgA2 used alone and the combination of the two neutralized the challenge virus equally well in vitro. All RMs given only i.v. HGN194 IgG1 became infected. In contrast, all RMs given HGN194 IgG1 + dIgA2 were completely protected against high-dose i.r. SHIV-1157ipEL-p challenge. These data imply that combining suboptimal defenses at the mucosal and systemic levels can completely prevent virus acquisition. Consequently, active vaccination should focus on defense-in-depth, a strategy that seeks to build up defensive fall-back positions well behind the fortified frontline. PMID:25769884

  14. Enhancing Virion Tethering by BST2 Sensitizes Productively and Latently HIV-infected T cells to ADCC Mediated by Broadly Neutralizing Antibodies

    PubMed Central

    Pham, Tram N. Q.; Lukhele, Sabelo; Dallaire, Frédéric; Perron, Gabrielle; Cohen, Éric A.

    2016-01-01

    Binding of anti-HIV antibodies (Abs) to envelope (Env) glycoproteins on infected cells can mark them for elimination via antibody-dependent cell-mediated cytotoxicity (ADCC). BST2, a type I interferon (IFN)-stimulated restriction factor that anchors nascent Env-containing virions at the surface of infected cells has been shown to enhance ADCC functions. In a comprehensive analysis of ADCC potency by neutralizing anti-HIV Abs (NAbs), we show in this study that NAbs are capable of mediating ADCC against HIV-infected T cells with 3BNC117, PGT126 and PG9 being most efficient. We demonstrate that HIV-induced BST2 antagonism effectively attenuates Ab binding and ADCC responses mediated by all classes of NAbs that were tested. Interestingly, IFNα treatment can reverse this effect in a BST2-dependent manner. Importantly, while reactivated latent T cell lines display some susceptibility to ADCC mediated by broadly NAbs, inactivating BST2 viral countermeasures and/or exogenous IFNα augment their elimination. Overall, our findings support the notion that NAbs can induce ADCC. They highlight that while BST2 antagonism by HIV promotes ADCC evasion, strategies aimed at restoring BST2 restriction could improve anti-HIV responses and potentially provide a means to eliminate reactivated cells in latent reservoirs. PMID:27853288

  15. Vitamin B-12 concentrations in breast milk are low and are not associated with reported household hunger, recent animal source food or vitamin B-12 intake among women in rural Kenya

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Breastmilk vitamin B-12 concentration may be inadequate in mothers living in regions where animal source food consumption is low or infrequent. Vitamin B-12 deficiency causes megaloglastic anemia and impairs growth and development in children. Objective: To measure vitamin B-12 in breast...

  16. Gastrointestinal Transcriptomic Response of Metabolic Vitamin B12 Pathways in Roux-en-Y Gastric Bypass

    PubMed Central

    Sala, Priscila; Belarmino, Giliane; Torrinhas, Raquel S; Machado, Natasha M; Fonseca, Danielle C; Ravacci, Graziela R; Ishida, Robson K; Guarda, Ismael F M S; de Moura, Eduardo G; Sakai, Paulo; Santo, Marco A; da Silva, Ismael D C G; Pereira, Claudia C A; Logullo, Angela F; Heymsfield, Steven; Giannella-Neto, Daniel; Waitzberg, Dan L

    2017-01-01

    Objectives: Vitamin B12 (B12) deficiency after Roux-en-Y gastric bypass (RYGB) is highly prevalent and may contribute to postoperative complications. Decreased production of intrinsic factor owing to gastric fundus removal is thought to have a major role, but other components of B12 metabolism may also be affected. We evaluated changes in the expression levels of multiple B12 pathway-encoding genes in gastrointestinal (GI) tissues to evaluate the potential roles in contributing to post-RYGB B12 deficiency. Methods: During double-balloon enteroscopy, serial GI biopsies were collected from 20 obese women (age, 46.9±6.2 years; body mass index, 46.5±5.3 kg/m2) with adult-onset type 2 diabetes (fasting plasma glucose ≥126 mg/dl; hemoglobin A1c≥6.5%) before and, at the same site, 3 months after RYGB. Gene expression levels were assessed by the Affymetrix Human GeneChip 1.0 ST microarray. Findings were validated by real-time quantitative PCR (RT–qPCR). Results: Gene expression levels with significant changes (P≤0.05) included: transcobalamin I (TCN1) in remnant (−1.914-fold) and excluded (−1.985-fold) gastric regions; gastric intrinsic factor (GIF) in duodenum (−0.725-fold); and cubilin (CUBN) in duodenum (+0.982-fold), jejunum (+1.311-fold), and ileum (+0.685-fold). Validation by RT–qPCR confirmed (P≤0.05) observed changes for TCN1 in the remnant gastric region (−0.132-fold) and CUBN in jejunum (+2.833-fold). Conclusions: RYGB affects multiple pathway-encoding genes that may be associated with postoperative B12 deficiency. Decreased TCN1 levels seem to be the main contributing factor. Increased CUBN levels suggest an adaptive genetic reprogramming of intestinal tissue aiming to compensate for impaired intestinal B12 delivery. PMID:28055029

  17. Biomarkers of folate and vitamin B12 and breast cancer risk: report from the EPIC cohort.

    PubMed

    Matejcic, M; de Batlle, J; Ricci, C; Biessy, C; Perrier, F; Huybrechts, I; Weiderpass, E; Boutron-Ruault, M C; Cadeau, C; His, M; Cox, D G; Boeing, H; Fortner, R T; Kaaks, R; Lagiou, P; Trichopoulou, A; Benetou, V; Tumino, R; Panico, S; Sieri, S; Palli, D; Ricceri, F; Bueno-de-Mesquita, H B As; Skeie, G; Amiano, P; Sánchez, M J; Chirlaque, M D; Barricarte, A; Quirós, J R; Buckland, G; van Gils, C H; Peeters, P H; Key, T J; Riboli, E; Gylling, B; Zeleniuch-Jacquotte, A; Gunter, M J; Romieu, I; Chajès, V

    2017-03-15

    Epidemiological studies have reported inconsistent findings for the association between B vitamins and breast cancer (BC) risk. We investigated the relationship between biomarkers of folate and vitamin B12 and the risk of BC in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Plasma concentrations of folate and vitamin B12 were determined in 2,491 BC cases individually matched to 2,521 controls among women who provided baseline blood samples. Multivariable logistic regression models were used to estimate odds ratios by quartiles of either plasma B vitamin. Subgroup analyses by menopausal status, hormone receptor status of breast tumors (estrogen receptor [ER], progesterone receptor [PR] and human epidermal growth factor receptor 2 [HER2]), alcohol intake and MTHFR polymorphisms (677C > T and 1298A > C) were also performed. Plasma levels of folate and vitamin B12 were not significantly associated with the overall risk of BC or by hormone receptor status. A marginally positive association was found between vitamin B12 status and BC risk in women consuming above the median level of alcohol (ORQ4-Q1  = 1.26; 95% CI 1.00-1.58; Ptrend  = 0.05). Vitamin B12 status was also positively associated with BC risk in women with plasma folate levels below the median value (ORQ4-Q1  = 1.29; 95% CI 1.02-1.62; Ptrend  = 0.03). Overall, folate and vitamin B12 status was not clearly associated with BC risk in this prospective cohort study. However, potential interactions between vitamin B12 and alcohol or folate on the risk of BC deserve further investigation.

  18. Lifestyle and genetic determinants of folate and vitamin B12 levels in a general adult population.