Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

With standard one- and two-dimensional proton NMR techniques, a common structural motif has been identified in water solutions of short peptide sequences derived from the envelope glycoprotein gp120 of HIV-1. Three peptides of lengths 12, 24, and 40 residues (termed RP342, RP142, and RP70, respectively) were synthesized, each containing a central amino acid sequence common to many HIV-1 isolates. In addition, RP70 contained a disulfide bond between cysteine residues close to the ends of the molecule, forming a loop that is thought to constitute an important structural and immunological component of the intact glycoprotein. Peptides RP70 and RP142 showed evidence for the presence of a significant population of conformations containing a beta-turn in the conserved sequence Gly-Pro-Gly-Arg. Strong nuclear Overhauser effect (NOE) connectivities were observed between the amide protons of the arginine and the adjacent glycine. A weak NOE connectivity was observed between the C alpha H of the proline residue and the NH of the Arg [a d alpha N(i,i + 2) NOE connectivity], confirming the presence of a conformational preference for a turn conformation in this sequence. The remainder of the peptide showed evidence of conformational averaging: no NMR evidence for a uniquely folded structure was obtained for any of the peptides in water solution. Circular dichroism (CD) spectra indicated that no ordered helix was present in water solutions of RP70, although a CD spectrum that indicated the presence of approximately 30% helix could be induced by the addition of trifluoroethanol.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Solution conformational preferences of immunogenic peptides derived from the principal neutralizing determinant of the HIV-1 envelope glycoprotein gp120. 189 28

A polyoxomolybdoeuropate PM-104 (NH4)12H2[Eu4(MoO4)(H2O)16(Mo7O24)4].13H2O was found to be a potent inhibitor of the growth of human immunodeficiency virus type 1 (HIV-1), a causative agent of acquired immunodeficiency syndrome (AIDS). On the basis of TI50 [median cytotoxic concentration (CC50)/median effective concentration (EC50)], the in vitro anti-HIV-1 activity of PM-104 is favorably comparable to that of a heteropolyoxotungstate PM-19 K7[PTi2W10O40].6H2O, which is one of the most potent HIV-1 inhibitors among the polyoxometalates so far tested. The heteropolyoxomolybdate with a potent anti-HIV-1 activity is introduced for the first time in this communication.
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PMID:Antiviral activity of polyoxomolybdoeuropate PM-104 against human immunodeficiency virus type 1. 193 91

The purpose of the study was to characterize in vivo an immunodepressive murine retroviral 'model' for the possible testing of drugs against HIV infection. Urethane leukaemia virus (ULV) injected into adult BALB/c mice (10(5) focus-forming units/mouse) caused a small, significant splenomegaly from 2 to at least 9 weeks after virus inoculation. Virus was also present in up to 60% nucleated splenocytes (XC 'infectious centre assay'). Effects on splenomegaly and virus in splenocytes were assayed following various regimens of zidovudine given as 0.5 mg/ml or 0.25 mg/ml in drinking water. Regimens included continuous treatment both before and after ULV, only before, and only after ULV inoculation. Zidovudine was also given for a limited period immediately after virus, or initiated after virus infection was established. Zidovudine given continuously at and following ULV infection completely prevented splenomegaly and virus expression in splenocytes. No other regimen was as effective; however, limited zidovudine treatment immediately after virus inoculation greatly reduced the effects of virus, while the same dose initiated after virus infection was established had only a small ameliorating effect. We conclude that ULV may prove to be a useful addition to other available murine systems, and this is discussed.
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PMID:Inhibition of urethane leukaemia virus, a murine retrovirus, in mice by zidovudine. 196 87

Aerosolized pentamidine has gained acceptance as a form of treatment for the prevention of Pneumocystis carinii pneumonia. However, different studies have used different delivery systems, making comparison of results difficult. This study was designed to determine the dose to the lung, regional distribution, extrapulmonary deposition, and side effects using four different delivery systems: the Respirgard II, the Aero Tech II, the Portasonic, and the Fisoneb. Ten homosexual subjects who were infected with HIV virus were studied. Particle size, as determined by cascade impaction, varied among nebulizers. Mass median aerodynamic diameter was 0.90 mu for the Respirgard II, 1.30 mu for the Aero Tech II, 1.40 mu for the Portasonic, and 3.90 mu for the Fisoneb. Subjects inhaled a solution containing 60 mg pentamidine in 3 ml of sterile water, and 1 ml of 99mTc bound to human serum albumin for each nebulizer system. Regional distribution was determined by comparing each deposition scan obtained by a posteriorly positioned gamma camera to the subjects' equilibrium xeon scan. The deposition scan was used to quantitate lung dose and extrapulmonary deposition. Marked differences were seen among delivery systems. Dose to the lung varied fivefold. The deposition in the lung, expressed as a percentage of the amount placed in the nebulizer, was 5.3 percent in the Respirgard II, 15.7 percent in the Aero Tech II, 17.30 percent in the Portasonic, and 26.4 percent in the Fisoneb (p less than 0.0001 by ANOVA). Wide differences in extrapulmonary deposition and side effects were noted among nebulizers (Fisoneb greater than Portasonic, Aero Tech II greater than Respirgard II). Regional distribution in the lung as measured by the AI, also showed differences, with the Respirgard having the most homogeneous distribution of aerosol (Respirgard greater than Portasonic, Aero Tech greater than Fisoneb). Regional distribution and extrapulmonary deposition varied in a manner consistent with the particle size of the nebulizers. These data should provide a framework for the comparison and design of future clinical studies using these delivery systems.
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PMID:Delivered dose and regional distribution of aerosolized pentamidine using different delivery systems. 201 69

Physicians investigated a nosocomial diarrhea outbreak among 11 2 year old undernourished children in the nutrition service of the pediatric teaching hospital, Hospital Infantile, in Mexico City, Mexico in April 1988. Health practitioners took at least 2 stool samples from each ill child to be analyzed for Cryptosporidium oocysts. The attack rate stood st 82%. The hospital admitted a malnourished child with chronic diarrhea and pneumonia on March 22. Laboratory tests revealed that he had many Cryptosporidium oocysts and was positive for HIV. Hospital staff did not isolate him. He died on May 9 of Escherichia coli and Candida septicemia. The outbreak ended 1 week later. Laboratory tests detected Cryptosporidium oocysts in 9 cases all of whom were 3-13 months old. Further the symptoms (mean duration 14 days, fever [mean peak 38.6 degrees Celsius, and vomiting] matched those of other reported Cryptosporidium diarrhea outbreaks. The epidemic curve suggested a common source of the outbreak. Since the infants received intravenous feedings or sterilized formula, food and water could not have been the source. The physicians believed the AIDS case was that source. Direct person to person transmission was probably not responsible since each infant had his/her own separate crib. Even though the physicians could not conclusively identify the vehicle of transmission, it was most likely the hands of hospitals staff either directly by touching the infants or by contaminating the nasogastric tubes. After the outbreak, the physicians observed that only 30% of medical personnel indeed washed their hands before caring for an infant. 4 previous studies on nosocomial Cryptosporidium diarrhea outbreaks also reported the source case as immunodeficient, but these studies only included adults.
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PMID:An outbreak of Cryptosporidium diarrhea in a pediatric hospital. 204 74

The purpose of this investigation was to study the knowledge about HIV infection and AIDS among dental students in Helsinki, Finland, and in Dar es Salaam, Tanzania. All respondents knew that HIV is not transmitted via hand-shaking, drinking water, or breathing air. More than half of the students in both countries did not know that HIV can be transmitted via breast-feeding. A higher proportion of students in Dar es Salaam than in Helsinki believed that all HIV-positive persons will get AIDS. Tanzanians recognized the early symptoms of HIV infection better than the Finnish students. Many students in both countries did not mention bisexual men as belonging to the high-risk group. Most of the dental students in Dar es Salaam but only one in five in Helsinki believed that dentists belong to the at-risk group.
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PMID:Dental students' knowledge of AIDS and HIV infection in Helsinki, Finland, and in Dar es Salaam, Tanzania. 205 32

A model system was developed previously for disposal of solid laboratory waste that is both radioactive and heat sensitive, e.g., HIV. A double polypropylene bag with charcoal vent filter and absorbent was designed to meet requirements for both steam sterilization and disposal as solid radioactive waste. Earlier work demonstrated the effective containment of radioactive gases by the filter and inactivation of organisms as heat sensitive as HIV. We sought to broaden the application of this model to ensure inactivation of microorganisms that are more heat resistant than HIV. The efficacy of steam sterilization using water or solutions of iodophor, hypochlorite, or hydrogen peroxide was studied under constant temperature and time conditions. The systems were monitored with internal probes, physical, chemical, and biological indicators. Biological indicators documented inactivation when bags containing hydrogen peroxide (3%) were autoclaved for 60 min at 121 degrees C. Synergistic activity between hydrogen peroxide and autoclave conditions significantly reduced processing time.
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PMID:Autoclave inactivation of infectious radioactive laboratory waste contained within a charcoal filtration system. 206 Oct 40

The conventionally applied centrifugation protocols for the concentration and purification of human immunodeficiency virus type 1 (HIV-1) result in a low recovery of the external glycoprotein, gp120. This is consistent with what has been found with other retroviruses. In the search for a method allowing the copurification of the gp120 with the virion we have applied two-phase extraction based on water-soluble polymers. Several polymer systems were tested for their capacity to enrich HIV-1 from HTLV-IIIB-infected H9 cell culture medium. With a dextran-polyethylene glycol system the gp120 and the gag protein p24, used as marker of the virion, were recovered to about 60 and 70%, respectively, in 1% of the initial volume. The two proteins were both about 30-fold purified and reverse transcriptase activity and infectious titer were retained to a high degree. The calculated molar ratio of gp120 to p24 was twofold higher in the phase-extracted fraction than in material pelleted by ultracentrifugation. It is concluded that extraction in aqueous two-phase systems is a method well suited for the concentration and initial purification of HIV-1. The technique is adaptable to almost any scale and may replace ultracentrifugation. Qualitatively, its main advantage over the latter method is the enhanced recovery of the gp120 in the virion fraction.
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PMID:Extraction of HIV-1 in aqueous two-phase systems to obtain a high yield of gp120. 207 15

Three water-soluble derivatives of amphotericin B were tested for inhibition of HIV infection in vitro. The compounds amphotericin B methyl ester (AME) and N-(N'-(2-(4'-methylmorpholinio)ethyl)N"-cyclohexyl guanyl) amphotericin B methyl ester (MCG) inhibited HIV infection by 50% at 1 microgram/ml; N-(N'-(3-dimethylaminopropyl)N"-ethyl guanyl) amphotericin B (DAPEG) did so at 5-11 micrograms/ml. While the virus-inhibitory effect of AME was due to an interaction with target lymphocytes, the effect of MCG was due to a direct anti-viral action. AME increased the potential of infected cells to fuse with uninfected cells, but MCG had no significant effect on cell fusion. All compounds had a lower cellular toxicity than amphotericin B and were not toxic at concentrations below 20 micrograms/ml.
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PMID:Derivatives of amphotericin inhibit infection with human immunodeficiency virus in vitro by different modes of action. 208 Aug 70

The brands of condom which are marketed in Denmark were examined for nonoxynol content with the object of assessing whether such content is sufficient to prevent HIV spread and in relation to defects in its potential effectiveness. Using the methods of methanol/water extraction and subsequent high performance liquid chromatography (with the standard nonoxynol content being 40 mg [100%] per condom), 1 brand of condom contained 65%, 2 contained 50-55%, and 4 between 25-33%. The nonoxynol content was found to be evenly distributed between the outer and inner surfaces of the condom. With a theoretical distribution volume of 6 ml (tearing during vaginal coitus), it was found that 3 brands of condom did not achieve the HIV-inhibiting nonoxynol concentration of 0.05%. This was ascertained by measuring the quantity of nonoxynol on the distal 5 cm of the condoms. During anal sex, the distribution volume is greater which results in lower nonoxynol concentrations and thus increased risk for HIV infection. It is concluded that nonoxynol content in the condoms marketed in Denmark should be increased in order to inactivate HIV in the event of condom failure. (author's modified)
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PMID:[The nonoxynol content in condoms is insufficient to inhibit the human immunodeficiency virus (HIV)]. 217 90


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