SARS-CoV-2 testing, positivity, and factors associated with COVID-19 among people with HIV across Europe in the multinational EuroSIDA cohort.

BACKGROUND: Although people with HIV might be at risk of severe outcomes from infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; coronavirus 2019 [COVID-19]), regional and temporal differences in SARS-CoV-2 testing in people with HIV across Europe have not been previously described. METHODS: We described the proportions of testing, positive test results, and hospitalizations due to COVID-19 between 1 January 2020 and 31 December 2021 in the EuroSIDA cohort and the factors associated with being tested for SARS-CoV-2 and with ever testing positive. RESULTS: Of 9012 participants, 2270 (25.2%, 95% confidence interval [CI] 24.3-26.1) had a SARS-CoV-2 polymerase chain reaction test during the study period (range: 38.3% in Northern to 14.6% in Central-Eastern Europe). People from Northern Europe, women, those aged <40 years, those with CD4 cell count <350 cells/mm3, and those with previous cardiovascular disease or malignancy were significantly more likely to have been tested, as were people with HIV in 2021 compared with those in 2020. Overall, 390 people with HIV (4.3%, 95% CI 3.9-4.8) tested positive (range: 2.6% in Northern to 7.1% in Southern Europe), and the odds of testing positive were higher in all regions than in Northern Europe and in 2021 than in 2020. In total, 64 people with HIV (0.7%, 95% CI 0.6-0.9) were hospitalized, of whom 12 died. Compared with 2020, the odds of positive testing decreased in all regions in 2021, and the associations with cardiovascular disease, malignancy, and use of tenofovir disoproxil fumarate disappeared in 2021. Among study participants, 58.9% received a COVID-19 vaccine (range: 72.0% in Southern to 14.8% in Eastern Europe). CONCLUSIONS: We observed large heterogeneity in SARS-CoV-2 testing and positivity and a low proportion of hospital admissions and deaths across the regions of Europe.

An Adaptive Study to Determine the Optimal Dose of the Tablet Formulation of the PARP Inhibitor Olaparib.

BACKGROUND: Olaparib is poorly soluble, requiring advanced drug delivery technologies for adequate bioavailability. Sixteen capsules/day are required for the approved 400 mg twice-daily dose; a tablet formulation was developed to reduce pill burden. This clinical trial evaluated the optimal dose and administration schedule of the tablet formulation. PATIENTS AND METHODS: Two stages of sequentially enrolled cohorts: stage 1, pharmacokinetic properties of tablet and capsule formulations were compared in patients with advanced solid tumours; stage 2, tablet dose escalation with expansion cohorts at doses/schedules of interest in patients with solid tumours and BRCAm breast/ovarian cancers. RESULTS: Olaparib 200 mg tablets displayed similar Cmax,ss, but lower AUCss and Cmin,ss than 400 mg capsules. Following multiple dosing, steady-state exposure with tablets ≥300 mg matched or exceeded that of 400 mg capsules. After dose escalation, while 400 mg twice daily was the tablet maximum tolerated dose based on haematological toxicity, 65 % of patients in the randomized expansion phase eventually required dose reduction to 300 mg. Intermittent tablet administration did not significantly improve tolerability. Tumour shrinkage was similar for 300 and 400 mg tablet and 400 mg capsule cohorts. CONCLUSIONS: The recommended monotherapy dose of olaparib tablet for Phase III trials was 300 mg twice daily, simplifying drug administration from 16 capsules to four tablets per day. CLINICAL TRIAL NUMBER: NCT00777582 (ClinicalTrials.gov).

Enhanced production of hydroxyl radicals by the xanthine-xanthine oxidase reaction in the presence of lactoferrin.

The generation of hydroxyl radicals by the xanthine-xanthine oxidase reaction (C. Beauchamp and I. Fridovich (1970) J. Biol. Chem. 245, 4641-1616) has been shown to be increased by iron-saturated lactoferrin isolated from pig neutrophils. Hydroxyl radical production, measured by EPR spin trapping and by ethylene production from alpha-keto-gamma-methiol butyric acid, has been demonstrated to be produced by a Fenton-type Haber-Weiss reaction catalysed by lactoferrin. The possibility that lactoferrin catalyses such a reaction in vivo is considered.

Effect of metal ion catalyzed oxidation of rifamycin SV on cell viability and metabolic performance of isolated rat hepatocytes.

The effect of rifamycin SV on metabolic performance and cell viability was studied using isolated hepatocytes from fed, starved and glutathione (GSH) depleted rats. The relationships between GSH depletion, nutritional status of the cells, glucose metabolism, lactate dehydrogenase (LDH) leakage and malondialdehyde (MDA) production in the presence of rifamycin SV and transition metal ions was investigated. Glucose metabolism was impaired in isolated hepatocytes from both fed and starved animals, the effect is dependent on the rifamycin SV concentration and is enhanced by copper (II). Oxygen consumption by isolated hepatocytes from starved rats was also increased by copper (II) and a partial inhibition due to catalase was observed. Cellular GSH levels which decrease with increasing the rifamycin SV concentration were almost depleted in the presence of copper (II). A correlation between GSH depletion and LDH leakage was observed in fed and starved cells. Catalase induced a slight inhibition of the impairment of gluconeogenesis, GSH depletion and LDH leakage in starved hepatocytes incubated with rifamycin SV, iron (II) and copper (II) salts. Lipid peroxidation measured as MDA production by isolated hepatocytes was also augmented by rifamycin SV and copper (II), especially in hepatic cells isolated from starved and GSH depleted rats. Higher cytotoxicity was observed in isolated hepatocytes from fasted animals when compared with fed or GSH depleted animals. It seems likely that in addition to GSH level, there are other factors which may have an influence on the susceptibility of hepatic cells towards xenobiotic induced cytotoxicity.

Isolation and characterization of superoxide dismutase: a personal history and tribute to Joe McCord and Irwin Fridovich.

The discovery of superoxide dismutase twenty years ago gave new meaning to work on erythrocuprein. This tribute to the achievement of Joe McCord and Irwin Fridovich is an account of experience of superoxide dismutase from old obscure copper protein of red blood cells to new exciting enzyme of oxygen free-radical metabolism, and an affirmation of the superoxide theory of oxygen toxicity.

Production of oxygen-centered radicals by neutrophils and macrophages as studied by electron spin resonance (ESR).

Neutrophils and macrophages undergo a respiratory burst and an increase in the activity of the hexose monophosphate pathway in response to particulate or soluble agents. The increase in oxygen consumption was found to be associated with the production of oxygen-centered radicals. The ESR technique of spin trapping showed that besides a superoxide spin adduct, a hydroxyl spin adduct is also produced. ESR is considered to be the least ambiguous technique for the detection of free radicals. The spin-trapping agents used for oxygen-centered radical detection are usually nitrones. The most commonly used nitrone is 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), which reacts with O2-. to form 5,5-dimethyl-2-hydroperoxypyrroline-N-oxide (DMPO-OOH) and with OH. to form 5,5-dimethyl-2-hydroxypyrroline-N-oxide (DMPO-OH). Although spin-adduct formation is considered to be the most direct technique for the detection of free radicals, some disadvantages are encountered. There has been considerable interest in the isolation of the O2-. generating activity from phagocytic cells. The enzyme can be extracted with deoxycholate and gel filtration indicates that it is a high molecular weight complex. Maximum activity was between pH 7.0 and pH 7.5. The Km value was 15.8 microM for NADPH and 434 micron for NADH, indicating that NADPH is the preferred substrate.

A time-resolved fluorescence study of human copper-zinc superoxide dismutase.

The intrinsic fluorescence decay of human Cu,Zn superoxide dismutase was measured by frequency-domain techniques. The protein consists of two subunits, each containing one tryptophan and no tyrosine residues. Using a synchrotron radiation source, which allows facile selection of the excitation wavelength, the dependence of the emission decay upon excitation was studied. No significant excitation wavelength effects were found. The two tryptophans contained in the dimer, although fully equivalent and exposed to solvent, showed a fluorescence decay that cannot be described by a single lifetime. Either two lifetimes, or one Lorentzian-shaped continuous distribution of lifetimes, are needed to obtain a good fit. Under identical experimental conditions, control experiments showed that N-acetyltryptophanamide, an analogue of tryptophanyl residues in proteins, decays with a single lifetime. The heterogeneous decay of tryptophan fluorescence in superoxide dismutase is interpreted as due to the presence of static and/or dynamic conformers in the protein that decay with different lifetimes. The two models of discrete lifetimes and continuous distribution of lifetimes are discussed with reference to measurements on holo- and apo-human superoxide dismutase.

The primary structure of human erythrocyte copper/zinc superoxide dismutase: cleavage with Staphylococcus aureus protease, determination of the N-terminal blocking group and location of the disulfide bond.

Results obtained after digestion of copper/zinc superoxide dismutase from human erythrocytes with S. aureus protease are described. In particular, peptides soluble in alkaline conditions proved essential for completing the determination of the primary structure of the enzyme; other peptides were important for establishing the amidation state of dicarboxylic amino acid residues and for confirming controversial sequences. The human enzyme is acetylated at the NH2 terminus and contains an intrasubunit disulfide bond connecting half-cystine residues 57 and 146.

Factors associated with HIV-1 virological failure in an outpatient clinic for HIV-infected people in Haiphong, Vietnam.

The objective of our study was to investigate factors associated with virological failure in 100 consecutive HIV-1 infected Vietnamese adults who initiated antiretroviral therapy (ART) from June 2007 to June 2008. Data were collected from medical records, and a structured questionnaire was used in individual interviews to investigate factors associated with adherence to ART. Plasma HIV viral load was measured at the time of the interview. The median age was 35 years, 35% were women and heterosexual intercourse was the most common mode of HIV transmission (61%). After a median of 14 months since starting ART, 23% had detectable HIV-1 viral load (≥ 400 copies/mL). Patients who had developed a World Health Organization (WHO) clinical stage 4 condition at the time of initiation of ART were more likely to experience virological failure than those in stages 1-3, odds ratio (OR): 5.20 (95% confidence interval [CI] 1.34-20.11), P = 0.017. Patients who reported that their health status was evaluated by a physician at each visit were less likely to experience virological failure, OR: 0.02 (95% CI 0.00-0.24), P = 0.002.