Cost-effectiveness of a multidimensional post-discharge disease management program for heart failure patients-economic evaluation along a one-year observation period.

OBJECTIVE: This study aimed to assess the cost-effectiveness of the telemedically assisted post-discharge management program (DMP) HerzMobil Tirol (HMT) for heart failure (HF) patients in clinical practice in Austria. METHODS: We conducted a cost-effectiveness analysis along a retrospective cohort study (2016-2019) of HMT with a propensity score matched cohort of 251 individuals in the HMT and 257 in the usual care (UC) group and a 1-year follow-up. We calculated the effectiveness (hospital-free survival, hospital-free life-years gained, and number of avoided rehospitalizations), costs (HMT, rehospitalizations), and the incremental cost-effectiveness ratio (ICER). We performed a nonparametric sensitivity analysis with bootstrap sampling and sensitivity analyses on costs of HF rehospitalizations and on costs per disease-related diagnosis (DRG) score for rehospitalizations. RESULTS: Base-case analysis showed that HMT resulted in an average of 42 additional hospital-free days, 40 additional days alive, and 0.12 avoided hospitalizations per patient-year compared with UC during follow-up. The average HMT costs were EUR 1916 per person. Mean rehospitalization costs were EUR 5551 in HMT and EUR 6943 in UC. The ICER of HMT compared to UC was EUR 4773 per life-year gained outside the hospital. In a sensitivity analysis, HMT was cost-saving when "non-HF related costs" related to the DMP were replaced with average costs. CONCLUSIONS: The economic evaluation along the cohort study showed that the HerzMobil Tirol is very cost-effective compared to UC and cost-saving in a sensitivity analysis correcting for "non-HF related costs." These findings promote a widespread adoption of telemedicine-assisted DMP for HF.

Evaluation of undetected cases during the COVID-19 epidemic in Austria.

BACKGROUND: Knowing the number of undetected cases of COVID-19 is important for a better understanding of the spread of the disease. This study analyses the temporal dynamic of detected vs. undetected cases to provide guidance for the interpretation of prevalence studies performed with PCR or antibody tests to estimate the detection rate. METHODS: We used an agent-based model to evaluate assumptions on the detection probability ranging from 0.1 to 0.9. For each general detection probability, we derived age-dependent detection probabilities and calibrated the model to reproduce the epidemic wave of COVID-19 in Austria from March 2020 to June 2020. We categorized infected individuals into presymptomatic, symptomatic unconfirmed, confirmed and never detected to observe the simulated dynamic of the detected and undetected cases. RESULTS: The calculation of the age-dependent detection probability ruled values lower than 0.4 as most likely. Furthermore, the proportion of undetected cases depends strongly on the dynamic of the epidemic wave: during the initial upswing, the undetected cases account for a major part of all infected individuals, whereas their share decreases around the peak of the confirmed cases. CONCLUSIONS: The results of prevalence studies performed to determine the detection rate of COVID-19 patients should always be interpreted with regard to the current dynamic of the epidemic wave. Applying the method proposed in our analysis, the prevalence study performed in Austria in April 2020 could indicate a detection rate of 0.13, instead of the prevalent ratio of 0.29 between detected and estimated undetected cases at that time.

Cost effectiveness of personalized treatment in women with early breast cancer: the application of OncotypeDX and Adjuvant! Online to guide adjuvant chemotherapy in Austria.

A Breast Cancer Outcomes model was developed at the ONCOTYROL research center to evaluate personalized test-treatment strategies in Austria. The goal was to evaluate the cost-effectiveness of a new 21-gene assay (ODX) when used in conjunction with the Adjuvant! Online (AO) decision aid to support personalized decisions about use of adjuvant chemotherapy in early-stage breast cancer patients in Austria. We applied a validated discrete-event-simulation model to a hypothetical cohort of 50 years old women over a lifetime horizon. The test-treatment strategies of interest were defined using three-letter acronyms. The first (second, third) letter indicates whether patients with a low (intermediate, high) risk according to AO were tested using ODX (Y yes, N no). The main outcomes were life-years gained, quality-adjusted life-years (QALYs), costs and cost effectiveness. Robustness of the results was tested in sensitivity analyses. Results were compared to a Canadian analysis conducted by the Toronto Health Economics and Technology Assessment Collaborative (THETA). Five of eight strategies were dominated (i.e., more costly and less effective: NNY, NYN, YNN, YNY, YYN). The base-case analysis shows that YYY (ODX provided to all patients) is the most effective strategy and is cost effective with an incremental cost-effectiveness ratio of 15,700 EUR per QALY gained. These results are sensitive to changes in the probabilities of distant recurrence, age and costs of chemotherapy. The results of the base-case analysis were comparable to the THETA results. Based on our analyses, using ODX in addition to AO is effective and cost effective in all women in Austria. The development of future genetic tests may require alternative or additional test-treatment strategies to be evaluated.

Decision-analytic modeling studies: An overview for clinicians using multiple myeloma as an example.

PURPOSE: The purpose of this study was to provide a clinician-friendly overview of decision-analytic models evaluating different treatment strategies for multiple myeloma (MM). METHODS: We performed a systematic literature search to identify studies evaluating MM treatment strategies using mathematical decision-analytic models. We included studies that were published as full-text articles in English, and assessed relevant clinical endpoints, and summarized methodological characteristics (e.g., modeling approaches, simulation techniques, health outcomes, perspectives). RESULTS: Eleven decision-analytic modeling studies met our inclusion criteria. Five different modeling approaches were adopted: decision-tree modeling, Markov state-transition modeling, discrete event simulation, partitioned-survival analysis and area-under-the-curve modeling. Health outcomes included survival, number-needed-to-treat, life expectancy, and quality-adjusted life years. Evaluated treatment strategies included novel agent-based combination therapies, stem cell transplantation and supportive measures. CONCLUSION: Overall, our review provides a comprehensive summary of modeling studies assessing treatment of MM and highlights decision-analytic modeling as an important tool for health policy decision making.

Use of DALYs in economic analyses on interventions for infectious diseases: a systematic review.

A systematic literature review was performed on full economic evaluations of infectious disease interventions using disability-adjusted life years (DALY) as outcome measure. The search was limited to the period between 1994 and September 2011 and conducted in Medline, SciSearch and EMBASE databases. We included 154 studies, mostly targeting HIV/AIDS and malaria with most conducted for African countries (40%) and <10% in high-income countries. Third-payer perspective was applied in 29% of the studies, 25% used the societal perspective and 12% used both. Only 16% of the studies took indirect effects (i.e. herd immunity) of interventions into account. Intervention, direct healthcare and indirect non-healthcare costs were taken into account in respectively 100%, 81% and 36% of the studies. The majority of the studies followed the Global Burden of Disease method for DALY estimations, but most studies deviated from WHO cost-effectiveness guidelines. Better adherence to freely accessible guidelines will improve generalizability between full economic evaluations.

A computational study of potential molecular switches that exploit Baird's rule on excited-state aromaticity and antiaromaticity.

A series of tentative single-molecule conductance switches which could be triggered by light were examined by computational means using density functional theory (DFT) with non-equilibrium Green's functions (NEGF). The switches exploit the reversal in electron counting rules for aromaticity and antiaromaticity upon excitation from the electronic ground state (S0) to the lowest ππ* excited singlet and triplet states (S1 or T1), as described by Hückel's and Baird's rules, respectively. Four different switches and one antifuse were designed which rely on various photoreactions that either lead from the OFF to the ON states (switches 1, 2 and 4, and antifuse 5) or from the ON to the OFF state (switch 3). The highest and lowest ideal calculated switching ratios are 1175 and 5, respectively, observed for switches 1 and 4. Increased thermal stability of the 1-ON isomer is achieved by benzannulation (switch 1B-OFF/ON). The effects of constrained electrode-electrode distances on activation energies for thermal hydrogen back-transfer from 1-ON to 1-OFF and the relative energies of 1-ON and 1-OFF at constrained geometries were also studied. The switching ratio is strongly distance-dependent as revealed for 1B-ON/OFF where it equals 711 and 148 when the ON and OFF isomers are calculated in electrode gaps with distances confined to either that of the OFF isomer or to that of the ON isomer, respectively.

cAMP signaling in Aspergillus fumigatus is involved in the regulation of the virulence gene pksP and in defense against killing by macrophages.

Aspergillus fumigatus is an important pathogen of immunocompromised hosts, causing pneumonia and invasive disseminated disease and resulting in high mortality. In order to determine the importance of the cAMP signaling pathway for virulence, three genes encoding putative elements of the pathway have been cloned and characterized: the adenylate cyclase gene acyA, and gpaA and gpaB, both of which encode alpha subunits of heterotrimeric G proteins. The acyA and gpaB genes were each deleted in A. fumigatus. Both mutants showed reduced conidiation, with the deltaacyA mutant producing very few conidia. The growth rate of the deltaacyA mutant was also reduced, in contrast to that of the deltagpaB mutant. Addition of 10 mM dibutyryl-cAMP to the culture medium completely restored the wild-type phenotype in both mutant strains. To study the influence of GPAB on the expression of the gene pksP, which encodes a virulence factor that is involved in pathogenicity, a pksPp-lacZ gene fusion was generated and integrated as a single copy at the pyrG gene locus of both the parental strain and the deltagpaB mutant strain. The deltagpaB mutant showed reduced expression of the pksPp-lacZ reporter gene relative to that in the parental strain. In mycelia of both the parental strain and the deltagpaB mutant pksPp-lacZ expression was increased when isobutyl-methyl-xanthine, an inhibitor of intracellular phosphodiesterases, was added to the medium. The survival rate of conidia after ingestion by human monocyte-derived macrophages was also determined. The killing rate for conidia from deltaacyA and deltagpaB strains was significantly higher than that for wild-type conidia. Taken together, these findings suggest that cAMP triggers a system that protects A. fumigatus from the effects of immune effector cells of the host.

Collagen sandwich culture affects intracellular polyamine levels of human hepatocytes.

Extracellular matrices, like collagen layers, play an important role in preventing dedifferentiation of hepatocytes in long-term culture experiments. It has also been shown that polyamines are crucial for cell growth and liver differentiation - regeneration. Primary cultured hepatocytes with their low mitotic activity might be a valuable tool in studying the role of polyamines in differentiation. Here, our goal was to investigate whether an extracellular cell culture matrix can influence intracellular polyamine levels in human hepatocytes during long-term culture. Primary human hepatocytes were isolated from surgical tissue resections and were maintained either in single collagen (SG) or double collagen gel (DG) layer (sandwich) culture systems. Cell viability and function were examined and intracellular polyamine levels were measured using a highly sensitive high performance liquid chromatography (HPLC) method. Hepatocytes showed high viability in both culture systems used, but albumin secretion was diminished in SG cultured hepatocytes after 14 days. In general, total intracellular polyamine levels of hepatocytes decreased markedly in both SG and DG within the first days of culture, but remained constant until day 21 with a SG/DG ratio of about 1.4. Individual polyamines levels were dependent on the culture time and system, where spermine decreased and putrescine increased in both SG and DG over time (day 14), but spermidine increased only in DG. Our results suggest that polyamine levels, in particular putrescine, might be important regulators of hepatocyte specific function in vitro and therefore serve as a marker of differentiation for cultivated human hepatocytes.

Differential expression of the Aspergillus fumigatus pksP gene detected in vitro and in vivo with green fluorescent protein.

Aspergillus fumigatus is an important pathogen of immunocompromised hosts, causing pneumonia and invasive disseminated disease with high mortality. To be able to analyze the expression of putative virulence-associated genes of A. fumigatus, the use of the enhanced green fluorescent protein (EGFP) as a reporter was established. Two 5' sequences, containing the putative promoters of the pyrG gene, encoding orotidine-5'-phosphate decarboxylase, and the pksP gene, encoding a polyketide synthase involved in both pigment biosynthesis and virulence of A. fumigatus, were fused with the egfp gene. The PpksP-egfp construct was integrated via homologous recombination into the genomic pksP locus. EGFP production was analyzed by fluorescence spectrometry, Western blot analysis, and fluorescence microscopy. Differential gene expression in A. fumigatus was observed. Fluorescence derived from the PYRG-EGFP fusion protein was detected during all developmental stages of the fungus, i.e., during germination, during vegetative growth, in conidiophores, and weakly in conidia. In addition, it was also detected in germinating conidia when isolated from the lungs of immunocompromised mice. By contrast, PKSP-EGFP-derived fluorescence was not found in hyphae or stalks of conidiophores but was found in phialides and conidia in vitro when the fungus was grown under standard conditions, indicating a developmentally controlled expression of the gene. Interestingly, pksP-egfp expression was also detected in hyphae of germinating conidia isolated from the lungs of immunocompromised mice. This finding indicates that the pksP gene can also be expressed in hyphae under certain conditions and, furthermore, that the pksP gene might also contribute to invasive growth of the fungus.

A rapid assay for evaluation of antiviral activity against coxsackie virus B3, influenza virus A, and herpes simplex virus type 1.

In order to identify new potential antiviral drugs, small amounts of extracts or compounds have to be examined for cytotoxicity and antiviral activity in primary screening using a rapid, easy, inexpensive, and highly standardised test system. In this study, high-throughput cytopathic effect (CPE) inhibitory assays were established for coxsackie virus B3 on HeLa Ohio cells, influenza virus A on Madin-Darby canine kidney cells, and herpes simplex virus type 1 (HSV-1) on green monkey kidney cells that meet these requirements. The cytotoxic and the antiviral effects were quantified using a crystal violet uptake assay allowing automated handling of large numbers of candidate agents. To ensure comparable results with plaque reduction assays, the 50 and 90% plaque inhibitory concentrations of guanidine, amantadine, and phosphonoformic acid were used to standardise the anti-coxsackie virus B3, anti-influenza virus A, and anti-HSV-1 tests, respectively. The strong correlation between the antiviral activity determined by CPE-inhibitory assays and plaque reduction assay was further proved for other antivirals. In summary, low amounts of large numbers of compounds may be tested inexpensively and standardised within 24 h (coxsackie virus B3 and influenza virus A) or 48 h (herpes simplex virus type 1) post-infection using CPE inhibitory assays.

Attachment of coxsackievirus B3 variants to various cell lines: mapping of phenotypic differences to capsid protein VP1.

The coxsackievirus B3 (CVB3) strain Nancy P establishes a persistent carrier-state infection without visible cytopathic effect in primary human fibroblasts (HuFi H), whereas the derivative variant PD induces a complete lysis of the cell monolayer. To define the molecular basis of this exceptional growth property, the complete genomes of both viruses were sequenced and compared to all published sequences of CVB3. As a result, six unique amino acid substitutions in the VP1 capsid protein were observed. Via hybrid virus construction, the lytic phenotype was transferred to a nonlytic cDNA-generated CVB3. Mapping experiments indicate that the presence of amino acid residues K78, A80, A91, and I92 in VP1 is sufficient to induce "lytic" infections in HuFi H cells. Binding assays demonstrate that CVB3 Nancy P preferentially binds to the human coxsackievirus-adenovirus receptor (CAR), while PD exhibits a very weak interaction with CAR but strong binding to the decay accelerating factor (DAF). These results suggest that the mutated amino acid residues in VP1 are involved in receptor recognition/binding. Moreover, the lytic replication of CVB3 PD and the hybrid virus in various nonpermissive rodent cell lines indicates that cell surface molecules other than CAR and DAF may be involved in attachment of this variant to cell surfaces.

Comparative evaluation of three different genotyping methods for investigation of nosocomial outbreaks of Legionnaires' disease in hospitals.

The increased incidence of nosocomial Legionnaires' disease in two hospitals prompted investigation of possible environmental sources. In the search for an effective DNA-typing technique for use in hospital epidemiology, the performance and convenience of three methods-SfiI macrorestriction analysis (MRA), amplified fragment length polymorphism (AFLP), and arbitrarily primed PCR (AP-PCR)-were compared. Twenty-nine outbreak-associated and eight nonassociated strains of Legionella pneumophila with 13 MRA types and subtypes were investigated. These strains comprised isolates from bronchoalveolar lavages, from environmental, patient-related sources, and type strains. All three typing methods detected one predominant genotype associated with the outbreaks in both hospitals. All of them correctly assigned epidemiologically associated, environmental isolates to their respective patient specimens. AP-PCR was the least discriminating and least reproducible technique. In contrast, AFLP was demonstrated as being the method with the best interassay reproducibility (90%) and concordance (94%) in comparison to the genotyping standard of MRA and the epidemiological data. Analysis of AFLP fragments revealed 12 different types and subtypes. Because of its simplicity and reproducibility, AFLP proved to be the most effective technique in outbreak investigation.

Interaction of human phagocytes with pigmentless Aspergillus conidia.

A defect in the pksP gene of Aspergillus fumigatus is associated with the loss of conidial pigmentation, a profound change of the conidial surface structure, and reduced virulence. The structural change of the conidial surface structure was not observed in similar A. nidulans wA mutants. Our data indicate that the pigment of both species is important for scavenging reactive oxygen species and for protection of conidia against oxidative damage.

Cobalt-deficiency-induced hyperhomocysteinaemia and oxidative status of cattle.

In ruminants, Co is required for the synthesis of vitamin B12, which in turn is needed for the resynthesis of methionine by methylation of homocysteine and thus, cobalamin deficiency may induce hyperhomocysteinaemia which is brought into context with perturbations of the antioxidative-prooxidative balance. The present study was conducted to explore whether Co deficiency in cattle is also associated with homocysteine-induced disturbances of oxidative status. Co deficiency was induced in cattle by feeding two groups of animals on either a basal maize-silage-based diet that was moderately low in Co (83 micrograms Co/kg DM), or the same diet supplemented with Co to a total of 200 micrograms Co/kg DM, for 43 weeks. Co deficiency was apparent from a reduced vitamin B12 status in serum and liver and an accumulation of homocysteine in plasma which was in excess of 4.8 times higher in Co-deprived cattle than in controls. The much increased level of circulating homocysteine did not indicate severe disturbances in antioxidant-prooxidant balance as measured by individual markers of lipid peroxidation, protein oxidation, and the antioxidative defence system. There were no quantitative difference in plasma thiol groups, nor were there significant changes in concentrations of alpha-tocopherol, microsomal thiobarbituric acid-reactive substances and carbonyl groups in liver. However, there was a trend toward increased plasma carbonyl levels indicating a slight degradation of plasma proteins in the hyperhomocysteinaemic cattle. Analysis of the hepatic catalase (EC 1.11.1.6) activity revealed an 11% reduction in Co-deficient cattle relative to the controls. These results indicate that long-term moderate Co deficiency may induce a severe accumulation of plasma homocysteine in cattle, but considerable abnormalities in oxidative status failed to appear.