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Taking first steps towards the installation of an innovative process chain for the discovery and production of new antimicrobials. N Biotechnol 2018. [DOI: 10.1016/j.nbt.2018.05.1034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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A systematic surveillance programme for infectious salmon anaemia virus supports its absence in the Pacific Northwest of the United States. JOURNAL OF FISH DISEASES 2018; 41:337-346. [PMID: 29159889 DOI: 10.1111/jfd.12733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 08/25/2017] [Accepted: 08/28/2017] [Indexed: 06/07/2023]
Abstract
In response to reported findings of infectious salmon anaemia virus (ISAV) in British Columbia (BC), Canada, in 2011, U.S. national, state and tribal fisheries managers and fish health specialists developed and implemented a collaborative ISAV surveillance plan for the Pacific Northwest region of the United States. Accordingly, over a 3-1/2-year period, 4,962 salmonids were sampled and successfully tested by real-time reverse-transcription PCR. The sample set included multiple tissues from free-ranging Pacific salmonids from coastal regions of Alaska and Washington and farmed Atlantic salmon (Salmo salar L.) from Washington, all representing fish exposed to marine environments. The survey design targeted physiologically compromised or moribund animals more vulnerable to infection as well as species considered susceptible to ISAV. Samples were handled with a documented chain of custody and testing protocols, and criteria for interpretation of test results were defined in advance. All 4,962 completed tests were negative for ISAV RNA. Results of this surveillance effort provide sound evidence to support the absence of ISAV in represented populations of free-ranging and marine-farmed salmonids on the northwest coast of the United States.
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The first-in-class alkylating HDAC inhibitor EDO-S101 is highly synergistic with proteasome inhibition against multiple myeloma through activation of multiple pathways. Blood Cancer J 2017; 7:e589. [PMID: 28753594 PMCID: PMC5549260 DOI: 10.1038/bcj.2017.69] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Carfilzomib resistance due to ABCB1/MDR1 overexpression is overcome by nelfinavir and lopinavir in multiple myeloma. Leukemia 2017; 32:391-401. [PMID: 28676669 PMCID: PMC5808083 DOI: 10.1038/leu.2017.212] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/21/2017] [Accepted: 06/26/2017] [Indexed: 12/18/2022]
Abstract
Proteasome inhibitor (PI) carfilzomib (CFZ) has activity superior to bortezomib (BTZ) and is increasingly incorporated in multiple myeloma (MM) frontline therapy and relapsed settings. Most MM patients ultimately experience PI-refractory disease, an unmet medical need with poorly understood biology and dismal outcome. Pharmacologic targeting of ABCB1 improved patient outcomes, including MM, but suffered from adverse drug effects and insufficient plasma concentrations. Proteomics analysis identified ABCB1 overexpression as the most significant change in CFZ-resistant MM cells. We addressed the functional role of ABCB1 overexpression in MM and observed significantly upregulated ABCB1 in peripheral blood malignant plasma cells (PCs) vs untreated patients' bone marrow PC. ABCB1 overexpression reduces the proteasome-inhibiting activity of CFZ due to drug efflux, in contrast to BTZ. Likewise, the cytotoxicity of established anti-MM drugs was significantly reduced in ABCB1-expressing MM cells. In search for potential drugs targeting ABCB1 in clinical trials, we identified the HIV protease inhibitors nelfinavir (NFV) and lopinavir (LPV) as potent functional modulators of ABCB1-mediated drug export, most likely via modulation of mitochondria permeability transition pore. NFV and LPV restored CFZ activity at therapeutically relevant drug levels and thus represent ready-to-use drugs to be tested in clinical trials to target ABCB1 and to re-sensitize PC to established myeloma drugs, in particular CFZ.
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Health care provider communication training in rural Tanzania empowers HIV-infected patients on antiretroviral therapy to discuss adherence problems. HIV Med 2017; 18:623-634. [PMID: 28296019 PMCID: PMC5599974 DOI: 10.1111/hiv.12499] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/07/2016] [Indexed: 12/30/2022]
Abstract
Objectives Self‐reported adherence assessment in HIV‐infected patients on antiretroviral therapy (ART) is challenging and may overestimate adherence. The aim of this study was to improve the ability of health care providers to elicit patients’ reports of nonadherence using a “patient‐centred” approach in a rural sub‐Saharan African setting. Methods A prospective interventional cohort study of HIV‐infected patients on ART for ≥ 6 months attending an HIV clinic in rural Tanzania was carried out. The intervention consisted of a 2‐day workshop for health care providers on patient‐centred communication and the provision of an adherence assessment checklist for use in the consultations. Patients’ self‐reports of nonadherence (≥ 1 missed ART dose/4 weeks), subtherapeutic plasma ART concentrations (< 2.5th percentile of published population‐based pharmacokinetic models), and virological and immunological failure according to the World Health Organization definition were assessed before and after (1–3 and 6–9 months after) the intervention. Results Before the intervention, only 3.3% of 299 patients included in the study reported nonadherence. Subtherapeutic plasma ART drug concentrations and virological and immunological failure were recorded in 6.5%, 7.7% and 14.5% of the patients, respectively. Two months after the intervention, health care providers detected significantly more patients reporting nonadherence compared with baseline (10.7 vs. 3.3%, respectively; P < 0.001), decreasing to 5.7% after 6–9 months. A time trend towards higher drug concentrations was observed for efavirenz but not for other drugs. The virological failure rate remained unchanged whereas the immunological failure rate decreased from 14.4 to 8.7% at the last visit (P = 0.002). Conclusions Patient‐centred communication can successfully be implemented with a simple intervention in rural Africa. It increases the likelihood of HIV‐infected patients reporting problems with adherence to ART; however, sustainability remains a challenge.
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27 Therapeutic immune recovery prevents emergence of CXCR4-tropic HIV-1. J Virus Erad 2016. [DOI: 10.1016/s2055-6640(20)30972-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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2′-Fluoro-2′,3′-Dideoxyarabinosyladenine (F-ddA): Activity against Drug-Resistant Human Immunodeficiency Virus Strains and Clades A-E. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/095632029700800204] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
2′-Fluoro-2′,3′-dideoxyarabinosyladenine (F-ddA), an anti-human immunodeficiency virus (HIV) drug currently in clinical trial, was compared with zidovudine (AZT), ddl and ddC for anti-HIV activity and potency in HIV-1 strains both sensitive and resistant to zidovudine, ddl and non-nucleoside reverse transcriptase inhibitors. A variety of host cell systems [MT-2, MT-4, phytohaemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC)] was used. F-ddA was effective against each of the drug-resistant isolates, including the strain resistant to ddl, the other purine dideoxynucleoside evaluated in this study. The anti-HIV-1 activities of F-ddA and zidovudine were also determined against clades A-E in PHA-PBMCs. Although activities were similar, zidovudine was significantly more potent than F-ddA in the PHA-PBMC system.
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Correlating HIV tropism with immunological response under combination antiretroviral therapy. HIV Med 2016; 17:615-22. [PMID: 26991140 DOI: 10.1111/hiv.12365] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2015] [Indexed: 01/14/2023]
Abstract
OBJECTIVES A significant percentage of patients infected with HIV-1 experience only suboptimal CD4 cell recovery while treated with combination therapy (cART). It is still unclear whether viral properties such as cell tropism play a major role in this incomplete immune response. This study therefore intended to follow the tropism evolution of the HIV-1 envelope during periods of suppressive cART. METHODS Viruses from two distinct patient groups, one with good and another one with poor CD4 recovery after 5 years of suppressive cART, were genotypically analysed for viral tropism at baseline and at the end of the study period. RESULTS Patients with CCR5-tropic CC-motif chemokine receptor 5 viruses at baseline tended to maintain this tropism to the study end. Patients who had a CXCR4-tropic CXC-motif chemokine receptor 4 virus at baseline were overrepresented in the poor CD4 recovery group. Overall, however, the majority of patients presented with CCR5-tropic viruses at follow-up. CONCLUSIONS Our data lend support to the hypothesis that tropism determination can be used as a parameter for disease progression even if analysed long before the establishment of a poorer immune response. Moreover, the lasting predominating CCR5-tropism during periods of full viral control suggests the involvement of cellular mechanisms that preferentially reduce CXCR4-tropic viruses during cART.
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The RNA of RNA-containing tumor viruses. BIBLIOTHECA HAEMATOLOGICA 2015:140-3. [PMID: 4376357 DOI: 10.1159/000391701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Biochemical studies on cells infectd with RNA-containing tumor viruses. BIBLIOTHECA HAEMATOLOGICA 2015; 30:34-6. [PMID: 4300010 DOI: 10.1159/000391214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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857: Aggravation of ER stress by combination of proteasome inhibitors and HIV protease inhibitors results in preferencial killing of triple-negative breast cancer cells in vitro. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)50760-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Positive effect of reduced aeration rate on secretion of alpha-amylase and neutral proteases during pressurised fermentation of thermophilic Bacillus caldolyticus. N Biotechnol 2014; 31:141-9. [PMID: 24239980 DOI: 10.1016/j.nbt.2013.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 10/08/2013] [Accepted: 10/25/2013] [Indexed: 01/26/2023]
Abstract
The thermophilic microorganism Bacillus caldolyticus was incubated in laboratory scale stirred bioreactors under pressurised conditions at different aeration rates. Increased amounts of CO2/bicarbonate were solubilised under the chosen conditions. A reduction in aeration rate from 1 vvm to 0.1 vvm resulted in accumulation of CO2 and bicarbonate up to 126 mg l(-1) and 733 mg l(-1), respectively and also increased secretion of α-amylase and neutral proteases (increases of 123% and 52%, respectively). In this paper, the effect of reduced aeration rate on CO2/bicarbonate concentration and enzyme activities is presented. The selected fermentation conditions are closely related to those prevalent in large scale bioreactors and may offer the possibility of achieving high enzyme yields at reduced aeration costs on an industrial scale.
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Nelfinavir augments proteasome inhibition by bortezomib in myeloma cells and overcomes bortezomib and carfilzomib resistance. Blood Cancer J 2013; 3:e103. [PMID: 23454896 PMCID: PMC3615215 DOI: 10.1038/bcj.2013.2] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
HIV protease inhibitors (HIV-PI) are oral drugs for HIV treatment. HIV-PI have antitumor activity via induction of ER-stress, inhibition of phospho-AKT (p-AKT) and the proteasome, suggesting antimyeloma activity. We characterize the effects of all approved HIV-PI on myeloma cells. HIV-PI were compared regarding cytotoxicity, proteasome activity, ER-stress induction and AKT phosphorylation using myeloma cells in vitro. Nelfinavir is the HIV-PI with highest cytotoxic activity against primary myeloma cells and with an IC50 near therapeutic drug blood levels (8–14 μM), irrespective of bortezomib sensitivity. Only nelfinavir inhibited intracellular proteasome activity in situ at drug concentrations <40 μℳ. Ritonavir, saquinavir and lopinavir inhibited p-AKT comparable to nelfinavir, and showed similar synergistic cytotoxicity with bortezomib against bortezomib-sensitive cells. Nelfinavir had superior synergistic activity with bortezomib/carfilzomib in particular against bortezomib/carfilzomib-resistant myeloma cells. It inhibited not only the proteasomal β1/β5 active sites, similar to bortezomib/carfilzomib, but in addition the β2 proteasome activity not targeted by bortezomib/carfilzomib. Additional inhibition of β2 proteasome activity is known to sensitize cells for bortezomib and carfilzomib. Nelfinavir has unique proteasome inhibiting activity in particular on the bortezomib/carfilzomib-insensitive tryptic (β2) proteasome activity in intact myeloma cells, and is active against bortezomib/carfilzomib-resistant myeloma cells in vitro.
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Concentrations of nonesterified fatty acids and glucose in blood of periparturient dairy cows are indicative of pregnancy success at first insemination. J Dairy Sci 2013; 96:181-8. [DOI: 10.3168/jds.2012-5619] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 09/06/2012] [Indexed: 11/19/2022]
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The 3-D time-dependent transport code TORT-TD and its coupling with the 3D thermal-hydraulic code ATTICA3D for HTGR applications. NUCLEAR ENGINEERING AND DESIGN 2012. [DOI: 10.1016/j.nucengdes.2011.09.067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Polyhydroxyalkanoates production and recovery with Ralstonia eutropha from plant and animal oils. N Biotechnol 2012. [DOI: 10.1016/j.nbt.2012.08.192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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923 Characterization of the Activity of Human Immunodeficiency Virus Protease Inhibitors Against Acute Myeloid Leukemia in Vitro. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71550-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Abstract
In this review article, the beneficial application of bacterial spore formers as probiotics in the food industry is discussed based on the knowledge gleaned from current publications. The summary of new scientific results provides evidence of the advantages of the utilisation of Bacillus or Clostridium strains in the food industry. Both bacteria are able to produce a very stable duration form: the endospore. Compared to the widely used lactic acid bacteria, bacterial spores offer the advantage of a higher survival rate during the acidic stomach passage and better stability during the processing and storage of the food product. In many food products, germination of the spores does not occur. Hence the product quality of the food is not affected because of their inactive metabolism. Besides the possible utilisation and functional properties, an overview of the fast-developing knowledge about the mechanisms of the beneficial health effects of spore-forming bacteria is provided.
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Cardiac response to exercise in normal-weight and obese, Hispanic men and women: implications for exercise prescription. Acta Physiol (Oxf) 2012; 205:113-23. [PMID: 21981898 DOI: 10.1111/j.1748-1716.2011.02371.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM The effects of obesity on cardiac function during incremental exercise to peak oxygen consumption (VO(2peak)) have not been previously described. The purpose of this study was to compare submaximal and maximal cardiac function during exercise in normal-weight and obese adults. METHODS Normal-weight (n = 20; means ± SE: age = 21.9 ± 0.5 years; BMI = 21.8 ± 0.4 kg m(-2)) and obese (n = 15; means ± SE: age = 25.1 ± 5.2 years; BMI = 34.1 ± 01.0 kg m(-2)) participants were assessed for body composition, VO(2peak) and cardiac variables (thoracic bioimpedance analysis) at rest and at heart rates (HR) of 110, 130, 150 and 170 beats min(-1) and maximal HR during incremental cycling exercise to exhaustion. Differences between groups were assessed with mixed-model ancova with repeated measures. Cardiac variables were statistically indexed for body surface area and resting HR. VO(2) and arteriovenous oxygen difference (a-vO(2)) were statistically indexed for fat-free mass and resting HR. RESULTS Significant main effects for group indicated obese participants had higher cardiac output (Q) index and stroke volume (SV) index but lower ejection fraction (EF) and a-vO(2) index during incremental exercise to exhaustion compared with their normal-weight peers, despite similar submaximal and maximal VO(2) and absolute power outputs (P < 0.05). CONCLUSIONS Our findings suggest that although Q index and SV index were higher in obese, young adults, EF and a-vO(2) index were significantly lower when compared to matched, normal-weight adults.
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Effect of partial pressure of CO2 on the production of thermostable alpha-amylase and neutral protease by Bacillus caldolyticus. PRIKLADNAIA BIOKHIMIIA I MIKROBIOLOGIIA 2012; 48:206-211. [PMID: 22586914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Controlling the concentration of dissolved oxygen is a standard feature in aerobic fermentation processes but the measurement of dissolved CO2 concentrations is often neglected in spite of its influence on the cellular metabolism. In this work room air and room air supplemented with 5% and 10% carbon dioxide were used for aeration during the cultivation of the thermophilic microorganism Bacillus caldolyticus (DSM 405) on starch to produce alpha-amylase (E.C. 3.2.1.1) and neutral protease (E.C. 3.4.24.27/28). The increased CO2 concentrations resulted in a 22% raise in activity of secreted alpha-amylase and a 43% raise in protease activity when compared with aeration with un-supplemented room air. There was no effect on the final biomass concentration. Furthermore, the lag-phase of fermentation was reduced by 30%, further increasing the productivity of alpha-amylase production. Determinations of dissolved CO2 in the culture broth were conducted both in situ with a probe as well as using exhaust gas analysis and both the methods of quantification showed good qualitative congruence.
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Effect of partial pressure of CO2 on the production of thermostable α-amylase and neutral protease by Bacillus caldolyticus. APPL BIOCHEM MICRO+ 2012. [DOI: 10.1134/s0003683812020032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Efficacy of chlorhexidine varnish for the prevention of adult caries: a randomized trial. J Dent Res 2011; 91:150-5. [PMID: 22156917 DOI: 10.1177/0022034511424154] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The Prevention of Adult Caries Study, an NIDCR-funded multicenter, double-blind, randomized clinical trial, enrolled 983 adults (aged 18-80 yrs) at high risk for developing caries (20 or more intact teeth and 2 or more lesions at screening) to test the efficacy of a chlorhexidine diacetate 10% weight per volume (w/v) dental coating (CHX). We excluded participants for whom the study treatment was contraindicated or whose health might affect outcomes or ability to complete the study. Participants were randomly assigned to receive either the CHX coating (n = 490) or a placebo control (n = 493). Coatings were applied weekly for 4 weeks and a fifth time 6 months later. The primary outcome (total net D(1-2)FS increment) was the sum of weighted counts of changes in tooth surface status over 13 months. We observed no significant difference between the two treatment arms in either the intention-to-treat or per-protocol analyses. Analysis of 3 protocol-specified secondary outcomes produced similar findings. This trial failed to find that 10% (w/v) chlorhexidine diacetate coating was superior to placebo coating for the prevention of new caries (Clinicaltrials.gov registration number NCT00357877).
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Die Bedeutung axonaler Pathologie für das Konzept der Neurodegeneration bei der Multiplen Sklerose. FORTSCHRITTE DER NEUROLOGIE-PSYCHIATRIE 2011; 79:161-70. [DOI: 10.1055/s-0029-1246014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
The purpose of this article is to review coculture fermentations in industrial biotechnology. Examples for the advantageous utilization of cocultures instead of single cultivations include the production of bulk chemicals, enzymes, food additives, antimicrobial substances and microbial fuel cells. Coculture fermentations may result in increased yield, improved control of product qualities and the possibility of utilizing cheaper substrates. Cocultivation of different micro-organisms may also help to identify and develop new biotechnological substances. The relevance of coculture fermentations and the potential of improving existing processes as well as the production of new chemical compounds in industrial biotechnology are pointed out here by means of more than 35 examples.
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Eine Möglichkeit zur Darstellung der Nierenfunktion im Röntgenbild. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1232014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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WE-B-213A-01: Medical Response to a Radiological/Nuclear Event. Med Phys 2009. [DOI: 10.1118/1.3182456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Chiral products from non-pyridine nucleotide-dependent reductases and methods for NAD(P)H regeneration. CIBA FOUNDATION SYMPOSIUM 2008; 111:97-111. [PMID: 3893942 DOI: 10.1002/9780470720929.ch8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Enoate reductase (EC 1.3.1.31) from a Clostridium tyrobutyricum strain catalyses the stereospecific reduction of many different alpha, beta-unsaturated carboxylates, aldehydes and even some ketones. The enzyme accepts electrons from NADH and, 1.5 times faster, from reduced methyl viologen (1,1'-dimethyl-4,4'-bipyridinium). Another new type of non-pyridine nucleotide-dependent reductase has an extremely broad substrate specificity for 2-oxo-carboxylates and 2-oxo-dicarboxylates. In crude extracts from Proteus mirabilis and Proteus vulgaris, specific activities of 2-12 mumol product formed per mg protein per min can be found when reduced methyl or benzyl viologen is used as electron donor. The products are (2R)-hydroxy acids. Enoate reductase and 2-oxo-carboxylate reductase are suitable for electro-enzymic reductions in which catalytic amounts of viologens are continuously reduced in an electrochemical cell. This procedure has three advantages: (1) regeneration of NAD(P)H by a second enzyme and substrate is not required, (2) the unstable pyridine nucleotides are not required in the reaction mixture, and (3) the rate of the reaction can be observed continuously by measuring an electric current. Several yeasts, as well as aerobic and anaerobic bacteria, catalyse the reduction of NAD(P)+ by reduced methyl viologen. Such cells can be used for electro-microbial reductions when only pyridine nucleotide-dependent reductases are present. Information about the enzymes which catalyse the reduction of NAD(P)+ at the expense of reduced methyl viologen is given.
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Abstract
A barrier to providing sealants is concern about inadvertently sealing over caries. This meta-analysis examined the effectiveness of sealants in preventing caries progression. We searched electronic databases for comparative studies examining caries progression in sealed permanent teeth. We used a random-effects model to estimate percentage reduction in the probability of caries progression in sealed vs. unsealed carious teeth. Six studies, including 4 randomized-controlled trials (RCT) judged to be of fair quality, were included in the analysis (384 persons, 840 teeth, and 1090 surfaces). The median annual percentage of non-cavitated lesions progressing was 2.6% for sealed and 12.6% for unsealed carious teeth. The summary prevented fraction for RCT was 71.3% (95%CI: 52.8%-82.5, no heterogeneity) up to 5 years after placement. Despite variation among studies in design and conduct, sensitivity analysis found the effect to be consistent in size and direction. Sealing non-cavitated caries in permanent teeth is effective in reducing caries progression.
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Natural product-based anti-HIV drug discovery and development facilitated by the NCI developmental therapeutics program. JOURNAL OF NATURAL PRODUCTS 2001; 64:265-277. [PMID: 11430019 DOI: 10.1021/np0003995] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
During the decade 1987-1996, the Developmental Therapeutics Program (DTP) of the National Cancer Institute (NCI) provided infrastructure support for both intramural and extramural anti-HIV (human immunodeficiency virus) drug discovery research and development. This retrospective review describes some of the anti-HIV lead discovery and development that took place under DTP auspices or which was substantially facilitated by resources made available through the DTP. Examples highlighted include leads identified through the initial screening of pure natural product derived compounds and those derived from bioassay-guided fractionation of crude natural product extracts, and these are classified according to the mechanism of action targeting the critical steps within the replication cycle of HIV.
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A flawed report on fractures? J Am Dent Assoc 2001; 132:146, 148. [PMID: 11217583 DOI: 10.14219/jada.archive.2001.0136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Management of dental patients who are HIV positive. EVIDENCE REPORT/TECHNOLOGY ASSESSMENT (SUMMARY) 2001:1-6. [PMID: 11291618 PMCID: PMC4781567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Prostate cancer: are new prognostic markers on the horizon? Prostate Cancer Prostatic Dis 2000; 3:62-65. [PMID: 12497101 DOI: 10.1038/sj.pcan.4500408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2000] [Revised: 05/04/2000] [Accepted: 05/18/2000] [Indexed: 11/09/2022]
Abstract
Current diagnostic methods in prostate cancer are lacking in their ability to predict individual patient outcome which highlights the need for more sensitive prognostic markers. Biological markers are seen as attractive and relevant candidates in current efforts to improve prognostic methods. Since metastasis is the most important component of cancer progression and mortality, markers which are able to predict the likely acquisition of the metastatic phenotype, before the onset of metastases, would be extremely useful clinically. This review outlines various metastasis suppressor genes and metastasis promoters which might have potential prognostic use in prostate cancer. Prostate Cancer and Prostatic Diseases (2000) 3, 62-65
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[Thank you to M. Souques and K. Zummer]. Presse Med 2000; 29:1001-2. [PMID: 10862253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
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[Psychic pain as a symptom of depression. Phenomenology and neurobiology]. FORTSCHRITTE DER NEUROLOGIE-PSYCHIATRIE 2000; 68:158-68. [PMID: 10803384 DOI: 10.1055/s-2000-11630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In a review of the relevant literature the experience of pain in depression is emphasized. There is evidence for a central pain disturbance mediating the 'psychic pain' experience in severe major depressive episodes with a predominance of anxiousness and agitation. This phenomenological concept has not been considered as a specific construct in modern descriptive classification systems such as DSM-IV or ICD-10. The purpose of this article is to provide an overview of recent partially independent developments in depression and experimental pain research with emphasis on the neuroanatomy of the rostral limbic system and the medial pain system. The available evidence is consistent with the hypothesis that overlapping anatomic structures of the medial pain system are activated during the experience of both the psychic pain of depression and the motivational-affective component of acute, tonic pain. This specific hypothesis can be tested with modern functional neuroimaging.
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Unique anti-human immunodeficiency virus activities of the nonnucleoside reverse transcriptase inhibitors calanolide A, costatolide, and dihydrocostatolide. Antimicrob Agents Chemother 1999; 43:1827-34. [PMID: 10428899 PMCID: PMC89377 DOI: 10.1128/aac.43.8.1827] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
(+)-Calanolide A (NSC 650886) has previously been reported to be a unique and specific nonnucleoside inhibitor of the reverse transcriptase (RT) of human immunodeficiency virus (HIV) type 1 (HIV-1) (M. J. Currens et al., J. Pharmacol. Exp. Ther., 279:645-651, 1996). Two isomers of calanolide A, (-)-calanolide B (NSC 661122; costatolide) and (-)-dihydrocalanolide B (NSC 661123; dihydrocostatolide), possess antiviral properties similar to those of calanolide A. Each of these three compounds possesses the phenotypic properties ascribed to the pharmacologic class of nonnucleoside RT inhibitors (NNRTIs). The calanolide analogs, however, exhibit 10-fold enhanced antiviral activity against drug-resistant viruses that bear the most prevalent NNRTI resistance that is engendered by amino acid change Y181C in the RT. Further enhancement of activity is observed with RTs that possess the Y181C change together with mutations that yield resistance to AZT. In addition, enzymatic inhibition assays have demonstrated that the compounds inhibit RT through a mechanism that affects both the K(m) for dTTP and the V(max), i.e., mixed-type inhibition. In fresh human cells, costatolide and dihydrocostatolide are highly effective inhibitors of low-passage clinical virus strains, including those representative of the various HIV-1 clade strains, syncytium-inducing and non-syncytium-inducing isolates, and T-tropic and monocyte-tropic isolates. Similar to calanolide A, decreased activities of the two isomers were observed against viruses and RTs with amino acid changes at residues L100, K103, T139, and Y188 in the RT, although costatolide exhibited a smaller loss of activity against many of these NNRTI-resistant isolates. Comparison of cross-resistance data obtained with a panel of NNRTI-resistant virus strains suggests that each of the three stereoisomers may interact differently with the RT, despite their high degree of structural similarity. Selection of viruses resistant to each of the three compounds in a variety of cell lines yielded viruses with T139I, L100I, Y188H, or L187F amino acid changes in the RT. Similarly, a variety of resistant virus strains with different amino acid changes were selected in cell culture when the calanolide analogs were used in combination with other active anti-HIV agents, including nucleoside and nonnucleoside RT and protease inhibitors. In assays with combinations of anti-HIV agents, costatolide exhibited synergy with these anti-HIV agents. The calanolide isomers represent a novel and distinct subgroup of the NNRTI family, and these data suggest that a compound of the calanolide A series, such as costatolide, should be evaluated further for therapeutic use in combination with other anti-HIV agents.
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Abstract
BACKGROUND Gait characteristic and muscle power are often described in the clinical literature but with little empirical support. We assessed some parameters of gait and muscle power using simple and standardized methods within a framework based principally on classic clinical observations of depression. METHOD 20 depressed inpatients were examined with standard tests of isometric muscle power and gait parameters, which measure step length, average walking speed, maximal walking speed, and three-minute walk distance. The results were compared with those of 20 matched healthy controls. The examination procedure was repeated after a three week period of inpatient treatment and significant symptomatic improvement. RESULTS As predicted by our hypothesis depressed patients' muscle power and gait characteristics differed clearly from normal controls. Significant improvements after 3 weeks of inpatient treatment were found above all in extension of the knee and extension of the elbow tests as well as in all measures of our gait analysis. However, all gait parameters still differed significantly from those of healthy controls. CONCLUSIONS Using simple but reliable tests which were used for the first time in psychiatry we examined certain relationships between depression and motor function in a moderately to severely depressed inpatient sample.
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[Incidence of immunogenic hyperthyroidism after radioiodine therapy of focal thyroid gland autonomy. Results of a multicenter study]. MEDIZINISCHE KLINIK (MUNICH, GERMANY : 1983) 1999; 94:239-44. [PMID: 10408185 DOI: 10.1007/bf03045047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND There are case reports in the literature that patients occasionally develop immunogenic hyperthyroidism 2 to 14 months following iodine-131-therapy of focal, non-immunogenic, autonomous thyroid nodules with a prevalence between 0.05 and 2.5%. Purpose of this multicenter evaluation was to assess the appearance of this phenomenon in a larger patient population. PATIENTS AND METHODS So far 2867 patients out of 4 university hospitals are included in our study focusing on the appearance of pathologically elevated levels of thyrotropin-receptor-antibodies (TRAb) combined with hyperthyroidism following iodine-therapy. Records of the patients were screened for pre- and post-therapeutic biochemical tests, scintigraphic uptake patterns and ultrasound findings of the thyroid. RESULTS Nineteen of 2867 patients with pretherapeutically scintigraphic "hot nodules" developed recurrent hyperthyroidism suggestive for immunogenic genesis 2 to 12 months following iodine-131-therapy (elevated TRAb-levels, homogeneous uptake in Tc-99m-pertechnetate scans). Pretherapeutically, 9 of these patients presented with a strictly focal scintigraphic uptake-pattern, 10 cases with a mixed disseminated-focal pattern. Because of missing pretherapeutic TRAb-tests in 8/9 patients presenting with a strictly focal scintigraphic uptake pattern, postradiogenic immunogenic hyperthyroidism could be reliably assessed in 1 case only. CONCLUSION One could speculate that iodine-131-therapy may stimulate immunogenic mechanisms finally leading to immunogenic hyperthyroidism. Posttherapeutically observed hyperthyroidism following iodine-treatment might be based on an exacerbation of a preexisting--clinically not relevant/detectable--immunothyropathia. Also pretherapeutic TRAb-negative immunogenic hyperthyroidism could not be definitely excluded. Our multicenter data collected in a large patient population show similar results to the case reports of immunogenic hyperthyroidism following iodine-131-treatment in smaller populations. Therfore, the occurrence of this phenomenon plays a minor role regarding to its prevalence. Therapeutical consequences in treatment of functional thyroid autonomy are not recommended.
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Abstract
During the past decade investigators paid increasing attention to psychomotor retardation and "volitional inhibition" as central elements of thinking and action in depression. In line with this is an increasing appreciation of some striking clinical parallels between particular aspects of Parkinson's disease and psychomotor manifestations of melancholia. We provide an update of the clinical literature regarding diagnostic problems and phenomenology of depressive states in Parkinson's disease and review their relation to cognitive impairments in neuropsychological task performance. We emphasize that many divergent results in older studies concerning Parkinson's disease and depression can be explained by methodological differences and shortcomings. Although the genesis, course, and treatment responsiveness of depressions in Parkinson's disease are still only partially understood, consensus regarding frequency and symptom features is gradually beginning to grow. Recent studies have shown that the occurrence of moderate to severe depressive states meeting the DSM-III-R criteria for Major Depressive Episode in community-based populations of Parkinson's disease patients is considerably lower (less than 10%) than the results of previous studies had suggested. However, a substantial proportion of predominantly younger patients have less severe but clinically significant depressive symptoms. Depression in Parkinson's disease patients is frequently associated with cognitive impairment. The issue of complex relationships between depression and primary, disease-related cognitive dysfunction in Parkinson's disease patients is dealt with in greater detail.
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Efficacy, pharmacokinetics, and in vivo antiviral activity of UC781, a highly potent, orally bioavailable nonnucleoside reverse transcriptase inhibitor of HIV type 1. AIDS Res Hum Retroviruses 1997; 13:789-96. [PMID: 9171223 DOI: 10.1089/aid.1997.13.789] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A series of compounds related to oxathiin carboxanilide has been identified as nonnucleoside reverse transcriptase inhibitors (NNRTIs) of HIV-1, and structure-activity relationships have been described (Buckheit RW, et al.: Antimicrob Agents Chemother 1995;39:2718-2727). Three new analogs (UC040, UC82, and UC781) inhibited laboratory and clinical isolates of HIV-1, including isolates representative of the various clades of HIV-1 found worldwide, in both established and fresh human cells. Virus isolates with the amino acid changes L100I, K103N, V106I, and Y181C in the reverse transcriptase were partially resistant to these compounds. However, UC781 inhibited these virus isolates at low nontoxic concentrations, presenting a broad in vitro therapeutic index. As with other NNRTIs, each of the compounds synergistically interacted with AZT to inhibit HIV-1 replication. UC781 possesses a favorable pharmacokinetic profile in mice with a high level of oral bioavailability. Plasma concentrations reached maximum levels within 2 to 4 hr of oral administration and remained in excess of those required for in vitro anti-HIV activity for at least 24 hr after a single oral dose. When evaluated in a murine hollow fiber implant model of HIV infection, UC781 dosed orally or parenterally was able to suppress HIV replication completely in this model system, providing evidence of the in vivo efficacy of the compound.
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Cross-resistance analysis and molecular modeling of nonnucleoside reverse transcriptase inhibitors targeting drug-resistance mutations in the reverse transcriptase of human immunodeficiency virus. Leukemia 1997; 11 Suppl 3:89-92. [PMID: 9209308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Oxathlin carboxanilide analogs (UC) and alpha APA, compounds recognized as nonnucleoside reverse transcriptase (RT) inhibitors (NNRTI), were evaluated for activity against the human immunodeficiency virus (HIV-1) and drug-resistant variants. These NNRTIs are structurally diverse but potent inhibitors of HIV-1 with efficacy in the nanomolar to low micromolar concentrations. They interact at a specific site in the pain domain of the p66 subunit of RT. Treatment of HIV-1 infected cell cultures with UC compounds resulted in the selection of drug-resistant viruses bearing specific amino acid changes at 100, 101, 103, 106, and/or 181. Since Y181C and L1001 are the most commonly observed resistance-engendering mutations, RT enzymatic analysis was correlated with molecular modeling to glean information on the structural interactions between these NNRTIs and RT. Information derived from these studies will facilitate rational drug design and the selection of complementary anti-HIV drugs for combination therapy.
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A new class of anti-HIV-1 agents targeted toward the nucleocapsid protein NCp7: the 2,2'-dithiobisbenzamides. Bioorg Med Chem 1997; 5:569-79. [PMID: 9113335 DOI: 10.1016/s0968-0896(96)00269-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
As part of the National Cancer Institute's Drug Screening Program, a new class of antiretrovirals active against the human immunodeficiency virus HIV-1 has been identified, and the HIV-1 nucleocapsid protein NCp7 was proposed as the target of antiviral action. The 2,2'-dithiobis-[4'-(sulfamoyl)benzanilide] (3x) and the 2,2'-dithiobis(5-acetylamino)benzamide (10) represented the prototypic lead structures. A wide variety of 2,2'-dithiobisbenzamides were prepared and tested for anti-HIV-1 activity, cytotoxicity, and their ability to extrude zinc from the zinc fingers for NCp7. The structure-activity relationships demonstrated that the ability to extrude zinc from NCp7 resided in the 2,2'-dithiobisbenzamide core structure. The 3,3' and the 4,4' isomers were inactive. While many analogs based upon the core structure retained the zinc extrusion activity, the best overall anti-HIV-1 activity was only found in a narrow set of derivatives possessing carboxylic acid, carboxamide, or phenylsulfonamide functional groups. These functional groups were more important for reducing cytotoxicity than improving antiviral potency or activity vs NCp7. All of the compounds with antiviral activity also extruded zinc from NCp7. From this study several classes of low microM anti-HIV agents with simple chemical structures were identified as possible chemotherapeutic agents for the treatment of AIDS.
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Abstract
Nucleocapsid p7 (NCp7) proteins of human immunodeficiency virus type 1 (HIV-1) contain two zinc binding domains of the sequence Cys-(X)2-Cys-(X)4-His-(X)4-Cys (CCHC). The spacing pattern and metal-chelating residues (3 Cys, 1 His) of these nucleocapside CCHC zinc fingers are highly conserved among retroviruses. These CCHC domains are required during both the early and late phases of retroviral replication, making them attractive targets for antiviral agents. toward that end, we have identified a number of antiviral chemotypes that electrophilically attack the sulfur atoms of the zinc-coordinating cysteine residues of the domains. Such nucleocapside inhibitors were directly virucidal by preventing the initiation of reverse transcription and blocked formation of infectious virus from cells through modification of CCHC domains within Gag precursors. Herein we report that azodicarbonamide (ADA) represents a new compound that inhibits HIV-1 and a broad range of retroviruses by targeting the the nucleocapsid CCHC domains. Vandevelde et al. also recently disclosed that ADA inhibits HIV-1 infection via an unidentified mechanism and that ADA was introduced into Phase I/II clinical trials in Europe for advanced AIDS. These studies distinguish ADA as the first known nucleocapsid inhibitor to progress to human trials and provide a lead compound for drug optimization.
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Immunogenicity and safety of a liquid combination of DTP-PRP-T [corrected] vs lyophilized PRP-T reconstituted with DTP. Vaccine 1997; 15:149-54. [PMID: 9066031 DOI: 10.1016/s0264-410x(96)00162-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The immunogenicity and safety of a combined diphtheria, tetanus, pertussis and Haemophilus influenzae type b-tetanus conjugate vaccine (DTP-PRP-T) was compared to the same combination obtained by the reconstitution of H. influenzae type b-tetanus conjugate vaccine lyophilized (PRP-T) with liquid diphtheria-tetanus-pertussis vaccine (DTP). Two hundred and sixty-two healthy infants were randomized to receive a intramuscular injection of 0.5 ml of one of the above combination vaccines at 2, 4 and 6 months of age, and a subgroup of 134 infants received a booster dose at 12 months. Serum antibody levels to each vaccine component were measured at ages 2, 6, 7, 12 and 13 months. Systemic and local reactions were assessed during the first 3 days after each injection by diary cards distributed to the parents. After the third dose and booster administered at 12 months of age, significant equivalence between the groups was observed, and the geometric mean titer of anti H. influenzae type b capsular polysaccharide (Hib-CP) antibodies were 5.9 and 32.6 micrograms ml-1 for the liquid combination group and 5.8 and 19.4 for the lyophilized group, respectively. After the third dose, anti-Hib-PC antibody levels of > or = 1.0 microgram ml-1 and 0.15 microgram ml-1 were seen in 94% and 100%, respectively, of the liquid combination group and 90 and 99%, respectively of the lyophilized group. After the booster dose, levels of > or = 1.0 microgram ml-1 were observed in 100% and 93.5% of the liquid combination group and the lyophilized combination group, respectively. Systemic and local reactions to the vaccination were generally mild and did not differ significantly between the groups. We conclude that the liquid combination of DTP-PRP-T is safe and at least as immunogenic as the lyophilized preparation. This liquid preparation, like other combined vaccines may be helpful for planning vaccination programs with a reduced number of injections.
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Inhibition of multiple phases of human immunodeficiency virus type 1 replication by a dithiane compound that attacks the conserved zinc fingers of retroviral nucleocapsid proteins. Antimicrob Agents Chemother 1997; 41:419-26. [PMID: 9021201 PMCID: PMC163723 DOI: 10.1128/aac.41.2.419] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) nucleocapsid p7 protein contains two retrovirus-type zinc finger domains that are required for multiple phases of viral replication. Chelating residues (three Cys residues and one His residue) of the domains are absolutely conserved among all strains of HIV-1 and other retroviruses, and mutations in these residues in noninfectious virions. These properties establish the zinc finger domains as logical targets for antiviral chemotherapy. Selected dithiobis benzamide (R-SS-R) compounds were previously found to inhibit HIV-1 replication by mediating an electrophilic attack on the zinc fingers. Unfortunately, reaction of these disulfide-based benzamides with reducing agents yields two monomeric structures (two R-SH structures) that can dissociated and no longer react with the zinc fingers, suggesting that in vivo reduction would inactivate the compounds. Through an extensive drug discovery program of the National Cancer Institute, a nondissociable tethered dithiane compound (1,2-dithiane-4,5-diol, 1,1-dioxide, cis; NSC 624151) has been identified. This compound specifically attacks the retroviral zinc fingers, but not other antiviral targets. The lead compound demonstrated broad antiretroviral activity, ranging from field isolates and drug-resistant strains of HIV-1 to HIV-2 and simian immunodeficiency virus. The compound directly inactivated HIV-1 virions and blocked production of infectious virus from cells harboring integrated proviral DNA. NSC 624151 provides a scaffold from which medicinal chemists can develop novel compounds for the therapeutic treatment of HIV infection.
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LDL stimulates chemotaxis of human monocytes through a cyclooxygenase-dependent pathway. Arterioscler Thromb Vasc Biol 1996; 16:1481-7. [PMID: 8977452 DOI: 10.1161/01.atv.16.12.1481] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Monocyte migration into the vessel wall is an early step in atherogenesis. Even though a number of chemotactic factors have been identified, the regulation of the chemotactic response is not clearly understood. As the release of arachidonic acid has been implicated in monocyte chemotaxis, we studied the influence of LDL, which can supply this fatty acid to cells, on the chemotactic mobility of monocytes. Migration of human monocytic U937 cells was abolished by a 30-hour incubation in medium containing lipoprotein-depleted 10% fetal calf serum. Thereafter, human VLDL, LDL, acetyl LDL, methyl LDL, HDL, free cholesterol, linoleic acid, oleic acid, or arachidonic acid was added. At the end of varying incubation periods (0.5 to 8 hours), chemotaxis, viability, and cellular cholesterol content were measured. In the same experimental setting we also studied the effects of the pharmacological agents chloroquine, indomethacin, and acetylsalicylic acid on LDL-mediated chemotaxis. Chemotaxis was restored by LDL in a dose- and time-dependent manner starting at concentrations as low as 5 micrograms/mL and at incubations as brief as 30 minutes. The other lipoproteins tested (VLDL, HDL, acetyl LDL, and methyl LDL) as well as free cholesterol had no comparable effect on chemotaxis. Viability and total cholesterol content did not differ among the groups. Simultaneous incubation of cells with chloroquine, indomethacin, and acetylsalicylic acid reduced restitution of chemotaxis by LDL by 71%, 82%, and 68%, respectively. In contrast, the agents had only slight inhibitory effects on the chemotactic mobility of serum-fed control cells. Incubation with linoleic acid showed a 60% restoration of chemotaxis, whereas arachidonic acid stimulated chemotaxis by 140% compared with the positive control. Preincubation of LDL with the monoclonal antibody MB47 directed against LDL resulted in a significantly reduced migratory response. The data suggest a novel cyclooxygenase-dependent regulatory mechanism of chemotaxis by LDL.
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Abstract
The anti-HIV sulfonated dye, resobene, was found to be a potent inhibitor of the attachment of HIV to target cells, the fusion of envelope- and CD4-expressing cells, and the cell-to-cell transmission of virus. Resobene inhibited the infection of phenotypically distinct, established human cell lines and fresh human peripheral blood lymphocytes and macrophages by laboratory-derived isolates of human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2), and a panel of biologically diverse primary clinical isolates, including syncytium-inducing and non-syncytium-inducing viruses and strains representative of the various virus clades found worldwide. The compound was also active against all drug-resistant virus isolates tested. Cell-based and biochemical mechanism of action studies demonstrated that the compound inhibits the attachment of infectious virus and fusion of virus-infected cells to uninfected target cells by binding to the cationic V3 loop of the envelope glycoprotein. Resobene effectively inhibited the infection of cell populations which do and do not express cell surface CD4. Resobene prevented infection of the cervical epithelial cell line ME180, suggesting the compound may effectively act as a topical microbicide to prevent the sexual transmission of HIV.
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Biological and biochemical anti-human immunodeficiency virus activity of UC 38, a new non-nucleoside reverse transcriptase inhibitor. J Pharmacol Exp Ther 1996; 276:298-305. [PMID: 8558446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
UC 38, a simple analog of oxathiin carboxanilide, UC 84, lacking the oxathiin ring, was found to be a potent inhibitor of human immunodeficiency virus (HIV)-1-induced cell killing and HIV replication in a variety of human cell lines, as well as in human peripheral blood lymphocytes and macrophages. UC 38 was active against a wide range of biologically diverse laboratory and clinical strains of HIV-1. However, UC 38 was inactive against HIV-2 and both nevirapine- and pyridinone-resistant strains of HIV-1. UC 38 selectively inhibited HIV-1 reverse transcriptase (RT), but not HIV-2 RT. Combination of UC 38 with 3'-azido-3'-deoxythymidine synergistically inhibited HIV-induced cell killing. An HIV-1 isolate resistant to UC 38 was selected in cell culture, and the mutations in the RT nucleotide sequences were determined. Comparison with the wild-type RT sequence revealed an amino acid change at position 181 (Tyr to Cys). The UC 38-resistant virus was found to be cross-resistant to a variety of structurally diverse non-nucleoside RT inhibitors. UC 38 was susceptible to rapid degradation in vitro and in vivo; yet, nontoxic in vivo concentrations of UC 38 many-fold in excess of the in vitro effective concentrations could be achieved and maintained after s.c. or p.o. administration in hamsters. These results establish UC 38 as a new chemotype within the general class of HIV-1-specific RT inhibitors. The favorable physical characteristics, lack of toxicity, potency and bioavailability of UC 38 may make it a candidate for combination chemotherapy of acquired immune deficiency syndrome.
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