| 1. |
- Beamish, A. J., et al.
(author)
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Changes in adipose tissue distribution and relation to cardiometabolic risk factors after Roux-en-Y in adolescents
- 2023
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In: Surgery for Obesity and Related Diseases. - : ELSEVIER SCIENCE INC. - 1550-7289 .- 1878-7533. ; 19:10, s. 1154-1161
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Journal article (peer-reviewed)abstract
- Background: Roux-en-Y gastric bypass (RYGB) among adolescents with obesity results in signif-icant weight loss; however, depot-specific changes have been understudied.Objective: We hypothesized that visceral adipose tissue (VAT) reduction in adolescents undergoing RYGB would be greater than other depots and associated with improvement in cardiometabolic risk factors.Setting: Three specialized treatment centers in Sweden. Methods: Fifty-nine adolescents underwent dual x-ray absorptiometry before surgery and at 1, 2, and 5 years after RYGB. Changes in body composition in multiple depots (total fat, lean body, gynoid fat, android fat, subcutaneous adipose tissue, and VAT) and cardiometabolic risk factors were assessed using multiple linear regression analysis and generalized estimating equations adjusting for age, sex, and baseline risk factor levels. Data are presented as percent change (95% CI) with regression models showing slopes and estimated P values.Results: At 1 year post-RYGB, a significant reduction was observed across all body composition measures (P , .001) with the greatest reduction observed in VAT (-65.1% [-68.7, -61.8]). From year 1 to 5 years post-RYGB, a regain was observed in all depots except lean body mass (1.2% [.3, 2.7], P 5 .105). A sex-specific difference in overall trajectories was only observed in lean body mass with males consistently having higher mean levels. Change in VAT at 1 year correlated with change in triglycerides (slope: .21 mg/dL/kg, P = .034) and fasting plasma insulin (slope: 44 pmol/L/kg, P = .027). Conclusions: Adiposity measures all decreased after RYGB but poorly predicted change in cardio-metabolic risk. Despite significant reductions at 1 year, a steady regain was observed out to 5 years, with values still well below baseline. Further research should consider control group comparison and extended follow-up.
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| 2. |
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| 3. |
- Lennerstrand, Johan, et al.
(author)
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A Method for Combined Immunoaffinity Purification and Assay of HIV-1 Reverse Transcriptase Activity Useful for Crude Samples
- 1996
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In: Analytical Biochemistry. - : Elsevier BV. - 0003-2697 .- 1096-0309. ; 235:2, s. 141-152
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Journal article (peer-reviewed)abstract
- Detection of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity in crude specimens was greatly enhanced using a novel capture RT assay. Eighteen different monoclonal antibodies (Mabs) raised against purified HIV-1 RT were tested for their ability to bind to HIV-1 RT without affecting its activity. The anti-HIV-1 RT Mabs were immobilized on plastic macrobeads and used as solid carriers in the capture RT assay. The assay system first involved RT's adherence to the immobilized Mabs. Nonspecific enzymes and other impurities were removed by a simple wash after which the RT reaction mixture was added. Substrate and product were finally separated by a wash of the beads. Practically all radioactivity incorporated into DNA (>98%) was recovered on the bead. The Michaelis-Menten constants and the saturation velocity values for the nucleotide substrate were similar for free and immobilized RT. The reaction mechanism for the immobilized RT is discussed. When comparing the function of this assay with more conventional soluble RT assays for samples consisting of recombinant HIV-1 RT mixed with an extract of peripheral blood lymphocytes (PBL), an almost 100-fold higher sensitivity was found. The capture RT assay had the capacity to recover approximately 80% of the RT activity added to an extract of 1 x 10(7) PBL cells/ ml. A strong correlation (r = 0.947) between the results obtained with this assay and a HIV-1 p24 enzyme-linked immunosorbent assay was found, when samples from a collection of 16 HIV strains propagated in cell culture were analyzed.
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| 4. |
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| 5. |
- Dahlgren, T., et al.
(author)
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Electronic spectra of dithieno analogues of phenanthrene
- 1979
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In: Chemical Physics. - : Elsevier BV. - 0301-0104. ; 40:3, s. 397-404
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Journal article (peer-reviewed)abstract
- The magnetic circular dichroism (MCD) spectra of some dithieno analogues of phenanthrene: benzo [2,1-b;3,4-b′] dithiophene (I) benzo [1,2-b;4,3-b′] dithiophene (II), benzo [1,2-c;3,4-c′] dithiophene (III) and benzo [1,2-b;3,4-b′] dithiophene (IV) are reported. For I–III the spectra corresponding to two different transition moment directions could be obtained from low-temperature linear dichroism spectra. The results compare well with theoretical energies, oscillator strengths, moment directions and MCD B-terms which were obtained from semi-empirical quantum mechanical calculations in the π-electron approximation.
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| 6. |
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| 7. |
- Gronowitz, J S, et al.
(author)
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Carrier bound templates for single tube reverse transcriptase assays and for combined purification and activity analyses, with special reference to HIV
- 1991
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In: Biotechnology and applied biochemistry. - 0885-4513 .- 1470-8744. ; 13:1, s. 127-142
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Journal article (peer-reviewed)abstract
- Polyriboadenosine (prA) was coupled to polycarbonate macrobeads or magnetic beads. The efficiency of the beads and of prA-Sepharose, after priming with odT, as templates in activity assays of purified AMV- and HIV-reverse transcriptase (RT), using [125I]iododeoxyuridine-triphosphate as substrate, was studied. Although the use of immobilized templates, compared with soluble template, resulted in a decreased total molar turnover, it did not affect the sensitivity of the assay for detecting RT. The utility of the new assay was analyzed by mixing purified AMV- or HIV-Rt with different dilutions of the untreated clinical specimen. This showed that RT activity was unaffected by 100 microliters of an extract of whole blood cells resuspended to their original blood volume and diluted 1/64, and also by 100 microliters of serum diluted 1/64. To improve the utility of the assay at the inhibitory concentrations of clinical specimens, the following procedure was adopted: the sample to be analyzed was incubated with the carrier bound template in order to allow the RT to bind, the carrier was washed to remove inhibitory factors, and the reaction components were then added to determine the amount of bound RT. This procedure greatly enhanced the recovery of RT activity from crude specimens and made the direct detection of HIV-RT possible. The assay is easily automated and useful for RT determination in multiple samples and for determining RT-inhibiting substances such as substrate analogs and antibodies.
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| 8. |
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| 9. |
- Larsson, P A, et al.
(author)
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Inhibition of herpes simplex virus replication and protein synthesis by non-smoked tobacco, tobacco alkaloids and nitrosamines
- 1992
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In: Archives of Oral Biology. - 0003-9969 .- 1879-1506. ; 37:11, s. 969-978
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Journal article (peer-reviewed)abstract
- Inhibitory effects of snuff extract and the tobacco chemicals nicotine, anabasine, diethyl-N-nitrosamine (DEN), and the tobacco-specific nitrosamines (TSNA), N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) on herpes simplex virus type 1 (HSV-1) replication in vitro and on HSV-1 protein synthesis in infected cells were analysed. Snuff extract and nicotine caused a significant reduction of HSV-1 attachment to cell membranes whereas anabasine, DEN, NNN and NNK did not affect adsorption of HSV-1. Virus production assays in the presence of snuff added after virus adsorption resulted in a significantly reduced production of virus at low multiplicities of infection (MOI), but at high MOI the inhibitory effect of snuff extract was less pronounced. DEN, NNN and NNK only affected virus production at toxic concentrations. Nicotine and anabasine reduced virus production in non-toxic doses but not at the concentrations present in snuff extract. In HSV-infected cells exposed to snuff extract, the immediate early (α-) infected cell proteins (ICPs) 4 and 27 (as well as the early (β-) ICPs 6 and 8) were markedly increased, whereas the late (γ-) ICPs 5, 11 and 29 were reduced. Nicotine had a less pronounced stimulating effect on the production of α-proteins but no detectable effect on production of β- or -γ-proteins. Anabasine, DEN, NNN and NNK did not affect HSV protein synthesis at non-toxic concentrations. Synthesis of thymidine kinase and DNA polymerase was significantly reduced by snuff extract. Also nicotine and anabasine affected thymidine kinase and DNA polymerase but only at toxic concentrations. The production of the cellular protein actin, which almost disappears a few hours after HSV-1 infection, remained at a significant level in HSV-infected cells exposed to snuff. Thus snuff extract blocks the replicative cycle of HSV at an early stage, which results in an increased production of α-proteins in the infected cells and in prolonged maintenance of cellular functions. This may be of importance for HSV-induced transformation and the development of HSV-associated tumours.
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| 10. |
- Neumüller, M, et al.
(author)
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HIV-1 reverse transcriptase inhibiting antibody titer in serum : relation to disease progression and to core-antibody levels.
- 1992
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In: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 36:4, s. 283-291
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Journal article (peer-reviewed)abstract
- A new assay for detecting inhibition of reverse transcriptase activity (the RT-i REA) was developed. This assay was standardized for screening serum samples for reverse transcriptase inhibiting antibodies (RT-iAb). High specificity (100%) and sensitivity (greater than 98%) were achieved with samples from HIV-negative individuals and HIV-infected individuals. The RT-i REA was also used in a study of the titers of RT-iAb in serum samples obtained from 33 HIV-infected homosexual men. The results confirmed the relation between decreasing RT-iAb levels and progression to late stages of the disease. Furthermore, a falling RT-iAb titer was observed in 14 of 15 individuals experiencing periods of severe clinical symptoms attributed to HIV-activity. In 7 of the patients the decline in RT-iAb titer began prior to severe clinical symptoms. The fall in RT-iAb titer also correlated with a reduction in core Ab level. The core Ab level has previously been reported to be a disease progression marker with considerable prognostic value. However, whereas all patients were positive for RT-iAb, 8 of the 33 patients did not have detectable core Ab. The use of RT-iAb titer as a marker of disease progression is discussed.
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