Screening for drugs of abuse: effect of heat-treating urine for safe handling of samples

Abstract Heating urine samples from high-risk patients for 1 h at 56 degrees C is no longer believed to completely inactivate human immunodeficiency virus (HIV; AIDS virus). To protect staff who are handling infectious samples such as those from drug-addiction units, heating at a higher temperature may be necessary. We report the stability to heat treatment (at 60, 70, and 100 degrees C) at pH 5.1 and 7.6 of some commonly abused drugs, namely, methadone, pethidine, amphetamine, the cocaine metabolite, benzoylecgonine, and the dextropropoxyphene metabolite nordextropropoxyphene. Heat-treating urine at 60 degrees C for 1.5 h or 70 degrees C for 1 h did not significantly affect the measured concentrations of these drugs. However, heat treatment at 100 degrees C for 1 h reduced the recovery of all the drugs. Benzoylecgonine and amphetamine were most susceptible to the different forms of heat treatment.

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Role of Vif in Stability of the Human Immunodeficiency Virus Type 1 Core

Journal of Virology ◽

10.1128/jvi.74.23.11055-11066.2000 ◽

2000 ◽

Vol 74 (23) ◽

pp. 11055-11066 ◽

Cited By ~ 53

Author(s):

Åsa Öhagen ◽

Dana Gabuzda

Keyword(s):

Human Immunodeficiency Virus ◽

Dna Synthesis ◽

Virus Entry ◽

Wild Type ◽

The Core ◽

Immunodeficiency Virus ◽

The Stability ◽

Hiv 1

ABSTRACT The Vif protein of human immunodeficiency virus type 1 (HIV-1) is important for virion infectivity. Previous studies have shown thatvif-defective virions exhibit structural abnormalities in the virus core and are defective in the ability to complete proviral DNA synthesis in acutely infected cells. We developed novel assays to assess the relative stability of the core in HIV-1 virions. Using these assays, we examined the role of Vif in the stability of the HIV-1 core. The integrity of the core was examined following virion permeabilization or removal of the lipid envelope and treatment with various triggers, including S100 cytosol, deoxynucleoside triphosphates, detergents, NaCl, and buffers of different pH to mimic aspects of the uncoating and disassembly process which occurs after virus entry but preceding or during reverse transcription.vif mutant cores were more sensitive to disruption by all triggers tested than wild-type cores, as determined by endogenous reverse transcriptase (RT) assays, biochemical analyses, and electron microscopy. RT and the p7 nucleocapsid protein were released more readily from vif mutant virions than from wild-type virions, suggesting that the internal nucleocapsid is less stably packaged in the absence of Vif. Purified cores could be isolated from wild-type but not vif mutant virions by sedimentation through detergent-treated gradients. These results demonstrate that Vif increases the stability of virion cores. This may permit efficient viral DNA synthesis by preventing premature degradation or disassembly of viral nucleoprotein complexes during early events after virus entry.

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Sensitivity to a Nonpeptidic Compound (RPR103611) Blocking Human Immunodeficiency Virus Type 1 Env-Mediated Fusion Depends on Sequence and Accessibility of the gp41 Loop Region

Journal of Virology ◽

10.1128/jvi.74.5.2142-2150.2000 ◽

2000 ◽

Vol 74 (5) ◽

pp. 2142-2150 ◽

Cited By ~ 31

Author(s):

Béatrice Labrosse ◽

Carole Treboute ◽

Marc Alizon

Keyword(s):

Human Immunodeficiency Virus ◽

Drug Resistance ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Conformational Changes ◽

Loop Region ◽

Immunodeficiency Virus ◽

The Stability ◽

Hiv 1

ABSTRACT The triterpene RPR103611 is an efficient inhibitor of membrane fusion mediated by the envelope proteins (Env, gp120-gp41) of CXCR4-dependent (X4) human immunodeficiency virus type 1 (HIV-1) strains, such as HIV-1LAI (LAI). Other X4 strains, such as HIV-1NDK (NDK), and CCR5-dependent (R5) HIV-1 strains, such as HIV-1ADA (ADA), were totally resistant to RPR103611. Analysis of chimeric LAI-NDK Env proteins identified a fragment of the NDK gp41 ectodomain determining drug resistance. A single difference at position 91, leucine in LAI and histidine in NDK, apparently accounted for their sensitivity or resistance to RPR103611. We had previously identified a mutation of isoleucine 84 to serine in a drug escape LAI variant. Both I84 and L91 are located in the “loop region” of gp41 separating the proximal and distal helix domains. Nonpolar residues in this region therefore appear to be important for the antiviral activity of RPR103611 and are possibly part of its target. However, another mechanism had to be envisaged to explain the drug resistance of ADA, since its gp41 loop region was almost identical to that of LAI. Fusion mediated by chimeric Env consisting of LAI gp120 and ADA gp41, or the reciprocal construct, was fully blocked by RPR103611. The gp120-gp41 complex of R5 strains is stable, relative to that of X4 strains, and this stability could play a role in their drug resistance. Indeed, when the postbinding steps of ADA infection were performed under mildly acidic conditions (pH 6.5 or 6.0), a treatment expected to favor dissociation of gp120, we achieved almost complete neutralization by RPR103611. The drug resistance of NDK was partially overcome by preincubating virus with soluble CD4, a gp120 ligand inducing conformational changes in the Env complex. The antiviral efficacy of RPR103611 therefore depends on the sequence of the gp41 loop and the stability of the gp120-gp41 complex, which could limit the accessibility of this target.

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Role of Hydrophobic Residues in the Central Ectodomain of gp41 in Maintaining the Association between Human Immunodeficiency Virus Type 1 Envelope Glycoprotein Subunits gp120 and gp41

Journal of Virology ◽

10.1128/jvi.78.9.4921-4926.2004 ◽

2004 ◽

Vol 78 (9) ◽

pp. 4921-4926 ◽

Cited By ~ 34

Author(s):

Joanne York ◽

Jack H. Nunberg

Keyword(s):

Human Immunodeficiency Virus ◽

Conformational Changes ◽

Envelope Glycoprotein ◽

Site Directed Mutagenesis ◽

Amino Acid Residues ◽

Virus Envelope ◽

Hydrophobic Residues ◽

Immunodeficiency Virus ◽

Mediate Cell ◽

The Stability

ABSTRACT The interaction between the gp120 and gp41 subunits of the human immunodeficiency virus envelope glycoprotein serves to stabilize the virion form of the complex and to transmit receptor-induced conformational changes in gp120 to trigger the membrane fusion activity of gp41. In this study, we used site-directed mutagenesis to identify amino acid residues in the central ectodomain of gp41 that contribute to the stability of the gp120-gp41 association. We identified alanine mutations at six positions, including four tryptophan residues, which result in mutant envelope glycoprotein complexes that fail to retain gp120 on the cell surface. These envelope glycoproteins readily shed their gp120 and are unable to mediate cell-cell fusion. These findings suggest an important role for the conserved bulky hydrophobic residues in stabilizing the gp120-gp41 complex.

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What's new about AIDS?

NEXUS: The Canadian Student Journal of Anthropology ◽

10.15173/nexus.v11i1.139 ◽

1993 ◽

Vol 11 (1) ◽

Author(s):

Aileen Gray

Keyword(s):

Human Immunodeficiency Virus ◽

Viral Evolution ◽

Aids Pandemic ◽

Immunodeficiency Virus ◽

Aids Virus ◽

The Media ◽

Host Parasite

AIDS is often portrayed by the media as an unusual virus. This paper places the AIDS virus in a number of different contexts to demonstrate that the AIDS pandemic is not a unique or a non·repeatable occurrence. Viral characteristics in general, and those of HIV (Human Immunodeficiency Virus) in particular, are examined, as are the concepts of viral evolution, human·virus interactions and host-parasite relationships.

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ATRIBUSI KOMUNIKASI ORANG DENGAN HIV/AIDS (ODHA) KEPADA KERABAT DEKAT DI YOGYAKARTA

Islamic Communication Journal ◽

10.21580/icj.2020.5.1.4775 ◽

2020 ◽

Vol 5 (1) ◽

pp. 83

Author(s):

Mugiarjo Mugiarjo

Keyword(s):

Human Immunodeficiency Virus ◽

Significant Others ◽

People Living With Hiv ◽

Self Disclosure ◽

Immunodeficiency Virus ◽

The Status ◽

The Stability ◽

Living With Hiv ◽

The Relationship ◽

Hiv Aids

<div>Regarding the response to self-disclosure, a person needs to make an attribution in order to know whether the response is really an intention or just a diversion. This article based on qualitative methods. Data collected by observation, interview, and documentation. The results of this study indicate that People Living With HIV/Aids (PLWHA) carry out quite strict regulations by conducting an assessment first before disclosing their Human Immunodeficiency Virus (HIV) status. The response obtained after they opened the status to the significant others was attributed by. The basis of sincere acceptance and response, the stability of the relationship between PLWHA and significant others after opening the status can be maintained, even stronger. PLWHA rely heavily on the power of spirituality to be able to build themselves better. In addition, the ability to make peace with oneself over their circumstances also influenced by this spirituality. Appreciation of spirituality also indicate that their engagement with God strengthened. This strength is shown by their awareness of the meaning of life.</div>

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Acceptability of Heat Treating Breast Milk to Prevent Mother-to-Child Transmission of Human Immunodeficiency Virus in Zimbabwe: A Qualitative Study

Journal of Human Lactation ◽

10.1177/0890334405283621 ◽

2006 ◽

Vol 22 (1) ◽

pp. 48-60 ◽

Cited By ~ 17

Author(s):

Kiersten A. Israel-Ballard ◽

M. Catherine Maternowska ◽

Barbara F. Abrams ◽

Pamela Morrison ◽

Livona Chitibura ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Breast Milk ◽

Qualitative Study ◽

Heat Treating ◽

Mother To Child Transmission ◽

Child Transmission ◽

Immunodeficiency Virus ◽

Mother To Child

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A national survey of disinfection techniques for flexible nasendoscopes in UK ENT out-patient departments

The Journal of Laryngology & Otology ◽

10.1258/0022215001905337 ◽

2000 ◽

Vol 114 (3) ◽

pp. 202-204 ◽

Cited By ~ 11

Author(s):

G. K. Banfield ◽

A. E. Hinton

Keyword(s):

Human Immunodeficiency Virus ◽

High Risk ◽

Financial Resources ◽

National Guidelines ◽

Immunodeficiency Virus ◽

Risk Patients ◽

Chemical Disinfectant ◽

Spread Of Infection ◽

Patient Use ◽

Disposable Plastic

Flexible fibre-optic nasendoscopes have become a ubiquitous ENT out-patient tool for the inspection of the nasopharynx, larynx and hypopharynx. Disinfection of the instrument between patient use is important to prevent potential spread of infection but the methods used vary considerably. We designed a questionnaire which was piloted and then sent to 115 UK ENT out-patient departments to establish current UK practice. Most units (67 per cent) use a chemical soak system but the type of chemical disinfectant, the method of delivery and the duration of soak varied considerably. A few hospitals use a disposable plastic sheath system and others simply wipe the instrument with an alcohol swab in between patient use. The protocols for disinfection after high risk patients e.g. human immunodeficiency virus (HIV), hepatitis B varied from hospital to hospital.The results demonstrate a lack of standard practice that is wasteful of financial resources and may expose patients to unnecessary risk. There is a need for an authoritative ENT body to publish national guidelines as may be found in other specialities and other countries.

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Mutations in the Thumb Allow Human Immunodeficiency Virus Type 1 Reverse Transcriptase To Be Cleaved by Protease in Virions

Journal of Virology ◽

10.1128/jvi.00676-09 ◽

2009 ◽

Vol 83 (23) ◽

pp. 12336-12344 ◽

Cited By ~ 17

Author(s):

Linda L. Dunn ◽

Mary Jane McWilliams ◽

Kalyan Das ◽

Eddy Arnold ◽

Stephen H. Hughes

Keyword(s):

Human Immunodeficiency Virus ◽

Reverse Transcriptase ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Viral Fitness ◽

Western Blots ◽

Immunodeficiency Virus ◽

The Stability ◽

Hiv 1

ABSTRACT Although human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) has been extensively studied, there are still significant questions about the effects of mutations on the maturation and stability of RT. We show here that a significant fraction (>80%) of the single point mutations we generated in the thumb subdomain of HIV-1 (RT) affect the stability of RT in virions. Fragments of the unstable mutant RTs can be detected in Western blots of virion proteins; however, the degree of degradation varies. The titers of the mutants whose virions contain degraded RTs are reduced. Some, but not all, of the unstable RT thumb subdomain mutants we analyzed have a temperature-sensitive phenotype. A preliminary survey of mutations in other subdomains of RT shows that some of these mutations also destabilize RT. The stability of the RT mutants is enhanced by the addition of a protease inhibitor, suggesting that the viral protease plays an important role in the degradation of the mutant RTs. These results confirm and extend earlier reports of mutations that affect the stability of RT in virions. The data suggest that the stability of a mutant RT in virions could be a major factor in determining the virus titer and, by extension, viral fitness, which could affect whether a mutation in RT is acceptable to the virus.

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