The Transmembrane Protease Serine 2 (TMPRSS2) Non-Protease Domains Regulating Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spike-Mediated Virus Entry

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters cells by binding to the angiotensin-converting enzyme 2 (hACE2) receptor. This process is aided by the transmembrane protease serine 2 (TMPRSS2), which enhances entry efficiency and infectiousness by cleaving the SARS-CoV-2 surface glycoprotein (Spike). The cleavage primes the Spike protein, promoting membrane fusion instead of receptor-mediated endocytosis. Despite the pivotal role played by TMPRSS2, our understanding of its non-protease distinct domains remains limited. In this report, we present evidence indicating the potential phosphorylation of a minimum of six tyrosine residues within the cytosolic tail (CT) of TMPRSS2. Via the use of TMPRSS2 CT phospho-mimetic mutants, we observed a reduction in TMPRSS2 protease activity, accompanied by a decrease in SARS-CoV-2 pseudovirus transduction, which was found to occur mainly via the endosomal pathway. We expanded our investigation beyond TMPRSS2 CT and discovered the involvement of other non-protease domains in regulating infection. Our co-immunoprecipitation experiments demonstrated a strong interaction between TMPRSS2 and Spike. We revealed a 21 amino acid long TMPRSS2-Spike-binding region (TSBR) within the TMPRSS2 scavenger receptor cysteine-rich (SRCR) domain that contributes to this interaction. Our study sheds light on novel functionalities associated with TMPRSS2's cytosolic tail and SRCR region. Both of these regions have the capability to regulate SARS-CoV-2 entry pathways. These findings contribute to a deeper understanding of the complex interplay between viral entry and host factors, opening new avenues for potential therapeutic interventions.

Method of Monitoring 26S Proteasome in Cells Revealed the Crucial Role of PSMA3 C-Terminus in 26S Integrity

Proteasomes critically regulate proteostasis via protein degradation. Proteasomes are multi-subunit complexes composed of the 20S proteolytic core particle (20S CP) that, in association with one or two 19S regulatory particles (19S RPs), generates the 26S proteasome, which is the major proteasomal complex in cells. Native gel protocols are used to investigate the 26S/20S ratio. However, a simple method for detecting these proteasome complexes in cells is missing. To this end, using CRISPR technology, we YFP-tagged the endogenous PSMB6 (β1) gene, a 20S CP subunit, and co-tagged endogenous PSMD6 (Rpn7), a 19S RP subunit, with the mScarlet fluorescent protein. We observed the colocalization of the YFP and mScarlet fluorescent proteins in the cells, with higher nuclear accumulation. Nuclear proteasomal granules are formed under osmotic stress, and all were positive for YFP and mScarlet. Previously, we have reported that PSMD1 knockdown, one of the 19 RP subunits, gives rise to a high level of "free" 20S CPs. Intriguingly, under this condition, the 20S-YFP remained nuclear, whereas the PSMD6-mScarlet was mostly in cytoplasm, demonstrating the distinct subcellular distribution of uncapped 20S CPs. Lately, we have shown that the PSMA3 (α7) C-terminus, a 20S CP subunit, binds multiple intrinsically disordered proteins (IDPs). Remarkably, the truncation of the PSMA3 C-terminus is phenotypically reminiscent of PSMD1 knockdown. These data suggest that the PSMA3 C-terminal region is critical for 26S proteasome integrity.

SARS-CoV-2 Omicron Specific Mutations Affecting Infectivity, Fusogenicity, and Partial TMPRSS2-Independency

The COVID-19 pandemic resulted from the global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since its first appearance in 2019, new SARS-CoV-2 variants of concern (VOCs) have emerged frequently, changing the infection's dynamic. SARS-CoV-2 infects cells via two distinct entry routes; receptor-mediated endocytosis or membrane fusion, depending on the absence or presence of transmembrane serine protease 2 (TMPRSS2), respectively. In laboratory conditions, the Omicron SARS-CoV-2 strain inefficiently infects cells predominantly via endocytosis and is phenotypically characterized by decreased syncytia formation compared to the earlier Delta variant. Thus, it is important to characterize Omicron's unique mutations and their phenotypic manifestations. Here, by utilizing SARS-CoV-2 pseudovirions, we report that the specific Omicron Spike F375 residue decreases infectivity, and its conversion to the Delta S375 sequence significantly increases Omicron infectivity. Further, we identified that residue Y655 decreases Omicron's TMPRSS2 dependency and entry via membrane fusion. The Y655H, K764N, K856N and K969N Omicron revertant mutations, bearing the Delta variant sequence, increased the cytopathic effect of cell-cell fusion, suggesting these Omicron-specific residues reduced the severity of SARS-CoV-2. This study of the correlation of the mutational profile with the phenotypic outcome should sensitize our alertness towards emerging VOCs.

Depleting the 19S proteasome regulatory PSMD1 subunit as a cancer therapy strategy

BACKGROUND

Proteasome inhibitors are in use in treating certain types of cancers. These drugs inhibit the catalytic activity of the 20S proteasome, shared by all the different proteasome complexes. Inhibitors of the 26S-associated deubiquitinating activity explicitly inhibit the 26S proteasomal degradation of ubiquitinylated substrates. We have previously reported an alternative strategy that is based on reducing the 26S/20S ratio by depleting PSMD1, 6, and 11, the subunits of the 19S proteasome regulatory complex. Given the addiction of the many cancer types to a high 26S/20S ratio, the depletion strategy is highly effective in killing many aggressive cancer cell lines but not mouse and human immortalized and normal cells.

METHODS

We used two aggressive cell lines, MDA-MB-231, a triple-negative breast tumor cell line, and OVCAR8, a high-grade ovary adenocarcinoma. Cell culture, mouse MDA-MB-231, OVCAR8 xenografts, and patient-derived ovarian cancer xenograft (PDX) models were transduced with lentivectors expressing PSMD1 shRNA. Tumor size was measured to follow treatment efficacy.

RESULTS

Using different experimental strategies of expressing shRNA, we found that PSMD1 depletion, either by expressing PSMD1 shRNA in an inducible manner or in a constitutive manner, robustly inhibited MDA-MB-231, and OVCAR8 xenograft tumor growth. Furthermore, the PSMD1 depletion strategy compromised the growth of the PDX of primary ovarian cancer.

CONCLUSION

Our results suggest that reducing the 26S/20S ratio might be a valuable strategy for treating drug-resistant aggressive types of cancers.

The C-Terminus of the PSMA3 Proteasome Subunit Preferentially Traps Intrinsically Disordered Proteins for Degradation

The degradation of intrinsically disordered proteins (IDPs) by a non-26S proteasome process does not require proteasomal targeting by polyubiquitin. However, whether and how IDPs are recognized by the non-26S proteasome, including the 20S complex, remains unknown. Analyses of protein interactome datasets revealed that the 20S proteasome subunit, PSMA3, preferentially interacts with many IDPs. In vivo and cell-free experiments revealed that the C-terminus of PSMA3, a 69-amino-acids-long fragment, is an IDP trapper. A recombinant trapper is sufficient to interact with many IDPs, and blocks IDP degradation in vitro by the 20S proteasome, possibly by competing with the native trapper. In addition, over a third of the PSMA3 trapper-binding proteins have previously been identified as 20S proteasome substrates and, based on published datasets, many of the trapper-binding proteins are associated with the intracellular proteasomes. The PSMA3-trapped IDPs that are proteasome substrates have the unique features previously recognized as characteristic 20S proteasome substrates in vitro. We propose a model whereby the PSMA3 C-terminal region traps a subset of IDPs to facilitate their proteasomal degradation.

Imatinib inhibits SARS-CoV-2 infection by an off-target-mechanism

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causal agent of the COVID-19 pandemic. More than 274 million individuals have suffered from COVID-19 and over five million people have died from this disease so far. Therefore, there is an urgent need for therapeutic drugs. Repurposing FDA approved drugs should be favored since evaluation of safety and efficacy of de-novo drug design are both costly and time consuming. We report that imatinib, an Abl tyrosine kinase inhibitor, robustly decreases SARS-CoV-2 infection and uncover a mechanism of action. We show that imatinib inhibits the infection of SARS-CoV-2 and its surrogate lentivector pseudotype. In latter, imatinib inhibited both routes of viral entry, endocytosis and membrane-fusion. We utilized a system to quantify in real-time cell-cell membrane fusion mediated by the SARS-CoV-2 surface protein, Spike, and its receptor, hACE2, to demonstrate that imatinib inhibits this process in an Abl1 and Abl2 independent manner. Furthermore, cellular thermal shift assay revealed a direct imatinib-Spike interaction that affects Spike susceptibility to trypsin digest. Collectively, our data suggest that imatinib inhibits Spike mediated viral entry by an off-target mechanism. These findings mark imatinib as a promising therapeutic drug in inhibiting the early steps of SARS-CoV-2 infection.

RNR-R2 Upregulation by a Short Non-Coding Viral Transcript

DNA viruses require dNTPs for replication and have developed different strategies to increase intracellular dNTP pools. Hepatitis B virus (HBV) infects non-dividing cells in which dNTPs are scarce and the question is how viral replication takes place. Previously we reported that the virus induces the DNA damage response (DDR) pathway culminating in RNR-R2 expression and the generation of an active RNR holoenzyme, the key regulator of dNTP levels, leading to an increase in dNTPs. How the virus induces DDR and RNR-R2 upregulation is not completely known. The viral HBx open reading frame (ORF) was believed to trigger this pathway. Unexpectedly, however, we report here that the production of HBx protein is dispensable. We found that a small conserved region of 125 bases within the HBx ORF is sufficient to upregulate RNR-R2 expression in growth-arrested HepG2 cells and primary human hepatocytes. The observed HBV mRNA embedded regulatory element is named ERE. ERE in isolation is sufficient to activate the ATR-Chk1-E2F1-RNR-R2 DDR pathway. These findings demonstrate a non-coding function of HBV transcripts to support its propagation in non-cycling cells.

Cyclic GMP-Dependent Regulation of Vascular Tone and Blood Pressure Involves Cysteine-Rich LIM-Only Protein 4 (CRP4)

The cysteine-rich LIM-only protein 4 (CRP4), a LIM-domain and zinc finger containing adapter protein, has been implicated as a downstream effector of the second messenger 3',5'-cyclic guanosine monophosphate (cGMP) pathway in multiple cell types, including vascular smooth muscle cells (VSMCs). VSMCs and nitric oxide (NO)-induced cGMP signaling through cGMP-dependent protein kinase type I (cGKI) play fundamental roles in the physiological regulation of vascular tone and arterial blood pressure (BP). However, it remains unclear whether the vasorelaxant actions attributed to the NO/cGMP axis require CRP4. This study uses mice with a targeted deletion of the CRP4 gene (CRP4 KO) to elucidate whether cGMP-elevating agents, which are well known for their vasorelaxant properties, affect vessel tone, and thus, BP through CRP4. Cinaciguat, a NO- and heme-independent activator of the NO-sensitive (soluble) guanylyl cyclase (NO-GC) and NO-releasing agents, relaxed both CRP4-proficient and -deficient aortic ring segments pre-contracted with prostaglandin F2α. However, the magnitude of relaxation was slightly, but significantly, increased in vessels lacking CRP4. Accordingly, CRP4 KO mice presented with hypotonia at baseline, as well as a greater drop in systolic BP in response to the acute administration of cinaciguat, sodium nitroprusside, and carbachol. Mechanistically, loss of CRP4 in VSMCs reduced the Ca2+-sensitivity of the contractile apparatus, possibly involving regulatory proteins, such as myosin phosphatase targeting subunit 1 (MYPT1) and the regulatory light chain of myosin (RLC). In conclusion, the present findings confirm that the adapter protein CRP4 interacts with the NO-GC/cGMP/cGKI pathway in the vasculature. CRP4 seems to be part of a negative feedback loop that eventually fine-tunes the NO-GC/cGMP axis in VSMCs to increase myofilament Ca2+ desensitization and thereby the maximal vasorelaxant effects attained by (selected) cGMP-elevating agents.

A SARS-CoV-2 neutralizing antibody selected from COVID-19 patients binds to the ACE2-RBD interface and is tolerant to most known RBD mutations

The novel betacoronavirus severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) causes a form of severe pneumonia disease called coronavirus disease 2019 (COVID-19). To develop human neutralizing anti-SARS-CoV-2 antibodies, antibody gene libraries from convalescent COVID-19 patients were constructed and recombinant antibody fragments (scFv) against the receptor-binding domain (RBD) of the spike protein were selected by phage display. The antibody STE90-C11 shows a subnanometer IC₅₀ in a plaque-based live SARS-CoV-2 neutralization assay. The in vivo efficacy of the antibody is demonstrated in the Syrian hamster and in the human angiotensin-converting enzyme 2 (hACE2) mice model. The crystal structure of STE90-C11 Fab in complex with SARS-CoV-2-RBD is solved at 2.0 Å resolution showing that the antibody binds at the same region as ACE2 to RBD. The binding and inhibition of STE90-C11 is not blocked by many known emerging RBD mutations. STE90-C11-derived human IgG1 with FcγR-silenced Fc (COR-101) is undergoing Phase Ib/II clinical trials for the treatment of moderate to severe COVID-19.

NQO1 Binds and Supports SIRT1 Function

Silent information regulator 2-related enzyme 1 (SIRT1) is an NAD⁺-dependent class III deacetylase and a key component of the cellular metabolic sensing pathway. The requirement of NAD⁺ for SIRT1 activity led us to assume that NQO1, an NADH oxidoreductase producing NAD⁺, regulates SIRT1 activity. We show here that SIRT1 is capable of increasing NQO1 (NAD(P)H Dehydrogenase Quinone 1) transcription and protein levels. NQO1 physically interacts with SIRT1 but not with an enzymatically dead SIRT1 H363Y mutant. The interaction of NQO1 with SIRT1 is markedly increased under mitochondrial inhibition. Interestingly, under this condition the nuclear pool of NQO1 is elevated. Depletion of NQO1 compromises the role of SIRT1 in inducing transcription of several target genes and eliminates the protective role of SIRT1 following mitochondrial inhibition. Our results suggest that SIRT1 and NQO1 form a regulatory loop where SIRT1 regulates NQO1 expression and NQO1 binds and mediates the protective role of SIRT1 during mitochondrial stress. The interplay between an NADH oxidoreductase enzyme and an NAD⁺ dependent deacetylase may act as a rheostat in sensing mitochondrial stress.

CRISPR Co-Editing Strategy for Scarless Homology-Directed Genome Editing

The clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 has revolutionized genome editing by providing a simple and robust means to cleave specific genomic sequences. However, introducing templated changes at the targeted site usually requires homology-directed repair (HDR), active in only a small subset of cells in culture. To enrich for HDR-dependent edited cells, we employed a co-editing strategy, editing a gene of interest (GOI) concomitantly with rescuing an endogenous pre-made temperature-sensitive (ts) mutation. By using the repair of the ts mutation as a selectable marker, the selection is "scarless" since editing restores the wild-type (wt) sequence. As proof of principle, we used HEK293 and HeLa cells with a ts mutation in the essential TAF1 gene. CRISPR co-editing of TAF1ts and a GOI resulted in up to 90% of the temperature-resistant cells bearing the desired mutation in the GOI. We used this system to insert large cassettes encoded by plasmid donors and smaller changes encoded by single-stranded oligonucleotide donors (ssODN). Of note, among the genes we edited was the introduction of a T35A mutation in the proteasome subunit PSMB6, which eliminates its caspase-like activity. The edited cells showed a specific reduction in this activity, demonstrating this system's utility in generating cell lines with biologically relevant mutations in endogenous genes. This approach offers a rapid, efficient, and scarless method for selecting genome-edited cells requiring HDR.

1247Similar rate of thermal esophageal lesions are found in patients alternatively assigned to high power short duration (70W, 8s) vs. lesion index guided (35W) ablation for atrial fibrillation

Background

wide antral pulmonary vein (PV) catheter ablation (CA) in patients with atrial fibrillation (AF) is safe and effective when permanent trans-mural lesions are achieved without causing harm to surrounding anatomical structures. Atrio-esophageal fistula, due to its high mortality, is the most dreadful complication related to CA for AF, therefore alternative radiofrequency (RF) approaches to reduce or eliminate this complication are currently studied. The shallower but wider lesions of high power short duration (HPSD) ablation might represent a safe alternative.

Purpose

to compare the rate of thermal esophageal lesions in patients with paroxysmal and persistent AF undergoing CA assigned to the 2 different RF modality.

Methods

one-hundred patients with paroxysmal and 100 with persistent AF will be alternatively assigned to undergo CA with the FlexAbility™ (HPSD group: 70W, 41°, 8 seconds) or the TactiCath™ (LSI-group: 35W, 41°, LSI: 5-5.5 posterior wall, up to 6 anywhere else) catheter. A 3-D mapping system, a steerable sheath and adenosine-test (30mg) were used in all patients. Posterior wall (PW) isolation in addition to PV isolation was performed in all, and patients with persistent AF were additionally treated with mitral and cavotricuspid isthmus ablation. Insertion of an esophageal probe was always attempted, and all patients underwent upper endoscopy 24 to 48 hours after CA.

Results

between June and October 2019, 71 patients (68 ± 10 years old, 32 (45%) female, 44 (60%) paroxysmal AF, AF duration 58 ± 81 months) were alternatively assigned to HPSD (36, 51%) or LSI-guided (35, 49%) ablation. No differences in clinical characteristics were found between groups. After 45 ± 18min and 30 ± 14 min of procedural and RF time, all PVs were isolated, and all spontaneous and adenosine-induced reconnections treated. Successful PW isolation was achieved with an additional 8 ± 3 and 7 ± 3 min of procedural and RF time. When HPSD and LSI-guided groups are compared, a similar rate of clinically non-relevant and self-healing thermal lesions at endoscopy was found (10, 27.8% vs. 10, 28.6%). Independent of the treatment group, a higher peak temperature identified patients with esophageal lesions (43.2° vs. 42°; P=.0065). A peak temperature value of 43.1° best identify patients most likely to develop thermal lesions (AUC 0.71, SE 84%, SP 39%). Interestingly, none of the 11 patients in whom esophageal probe insertion was not possible or attempted developed thermal lesions in comparison to 20 (33%) patients who underwent esophageal temperature monitoring (P=.0046). Conclusions: no difference in thermal induced esophageal lesions were found when the two different RF approach (HPSD vs. LSI guided) were compared. Interestingly, lack of temperature monitoring with an esophageal probe is associated with no thermal lesions at endoscopy.

Recruitment of DNA Repair MRN Complex by Intrinsically Disordered Protein Domain Fused to Cas9 Improves Efficiency of CRISPR-Mediated Genome Editing

CRISPR/Cas9 is a powerful tool for genome editing in cells and organisms. Nevertheless, introducing directed templated changes by homology-directed repair (HDR) requires the cellular DNA repair machinery, such as the MRN complex (Mre11/Rad50/Nbs1). To improve the process, we tailored chimeric constructs of Cas9, in which SpCas9 was fused at its N- or C-terminus to a 126aa intrinsically disordered domain from HSV-1 alkaline nuclease (UL12) that recruits the MRN complex. The chimeric Cas9 constructs were two times more efficient in homology-directed editing of endogenous loci in tissue culture cells. This effect was dependent upon the MRN-recruiting activity of the domain and required lower amounts of the chimeric Cas9 in comparison with unmodified Cas9. The new constructs improved the yield of edited cells when making endogenous point mutations or inserting small tags encoded by oligonucleotide donor DNA (ssODN), and also with larger insertions encoded by plasmid DNA donor templates. Improved editing was achieved with both transfected plasmid-encoded Cas9 constructs as well as recombinant Cas9 protein transfected as ribonucleoprotein complexes. Our strategy was highly efficient in restoring a genetic defect in a cell line, exemplifying the possible implementation of our strategy in gene therapy. These constructs provide a simple approach to improve directed editing.

A-77 Validity Testing with Youth Populations: D-KEFS Trail Making Test Conditions 4:2 Ratio as an Embedded Validity Indicator

Objective

The Trail Making Test B:A ratio is an embedded validity indicator (EVI) for neuropsychological assessment (NA; Ruffolo, Guilmette, & Willis, 2000). Recent literature supports D-KEFS Trail Making Test Conditions 4:2 (analogous to B:A) ratio (D-KEFS 4:2) as an EVI (Erdodi et al., 2018). The present study sought to assess the utility of D-KEFS 4:2 as an EVI for youth populations, using the Test of Memory Malingering (TOMM) to operationalize effort.

Method

102 children (81.2% male, Mage = 11.88) completed a NA, including D-KEFS 4:2 and TOMM. Receiver operator characteristics (ROC) curve analysis calculating Area Under the Curve (AUC) determined whether D-KEFS 4:2 accurately categorized participants’ effort (represented by TOMM performance).

Results

D-KEFS 4:2 (cut-off = 1.60: Erdodi et al., 2018) produced sensitivity of 9.09% and specificity of 91.25% in predicting TOMM performance on Trial 1 (TOMM1; AUC = 0.488) and 0.00% and 91.09% in predicting Trial 2 (TOMM2; AUC = 0.772). As a TOMM2 cut-off of 49 is suggested as more sensitive to inadequate effort, another analysis showed D-KEFS 4:2 yielded sensitivity of 33.33% and specificity of 91.92% (AUC = 0.710) in predicting TOMM2 performance with the more conservative cutoff.

Conclusions

This study suggests that D-KEFS 4:2 is an adequate EVI in predicting suboptimal effort when operationalized by TOMM performance, particularly when more conservative TOMM cutoffs are used. D-KEFS 4:2 detected true effortful performance with excellent specificity but exhibited poor detection of suboptimal performance. As a result, D-KEFS 4:2 has utility as an EVI in youth populations, but should not be used independently.

Oncogenic addiction to high 26S proteasome level

Proteasomes are large intracellular complexes responsible for the degradation of cellular proteins. The altered protein homeostasis of cancer cells results in increased dependency on proteasome function. The cellular proteasome composition comprises the 20S catalytic complex that is frequently capped with the 19S regulatory particle in forming the 26S proteasome. Proteasome inhibitors target the catalytic barrel (20S) and thus this inhibition does not allow the deconvolution of the distinct roles of 20S versus 26S proteasomes in cancer progression. We examined the degree of dependency of cancer cells specifically to the level of the 26S proteasome complex. Oncogenic transformation of human and mouse immortalized cells with mutant Ras induced a strong posttranscriptional increase of the 26S proteasome subunits, giving rise to high 26S complex levels. Depletion of a single subunit of the 19S RP was sufficient to reduce the 26S proteasome level and lower the cellular 26S/20S ratio. Under this condition the viability of the Ras-transformed MCF10A cells was severely compromised. This observation led us to hypothesize that cancer cell survival is dependent on maximal utilization of its 26S proteasomes. We validated this possibility in a large number of cancer cell lines and found that partial reduction of the 26S proteasome level impairs viability in all cancer cells examined and was not correlated with cell doubling time or reduction efficiency. Interstingly, normal human fibroblasts are refractory to the same type of 26S proteasome reduction. The suppression of 26S proteasomes in cancer cells activated the UPR and caspase-3 and cells stained positive with Annexin V. In addition, suppression of the 26S proteasome resulted in cellular proteasome redistribution, cytoplasm shrinkage, and nuclear deformation, the hallmarks of apoptosis. The observed tumor cell-specific addiction to the 26S proteasome levels sets the stage for future strategies in exploiting this dependency in cancer therapy.

Association of Neglect-Like Symptoms with Anxiety, Somatization, and Depersonalization in Complex Regional Pain Syndrome

Background

Many patients with complex regional pain syndrome (CRPS) report some foreignness of the affected limb, which is referred to as "neglect-like symptoms" (NLS). Despite similarities of the NLS reports to symptoms of body image disturbances in mental disorders, no study has been conducted to examine such associations.

Methods

We investigated 50 patients with CRPS and 45 pain control patients (N = 27, chronic limb pain; N = 18, migraine headache). NLS, anxiety, depression, depersonalization, and somatization were assessed using validated questionnaires.

Results

Seventy-two percent of the CRPS patients reported at least one NLS vs 29.6% and 33.3% in the two patient control groups. In limb pain controls, NLS correlated with pain intensity. In CRPS patients, NLS correlated with anxiety (rho = 0.658, P  < 0.001), somatization (rho = 0.616, P  < 0.001), depersonalization (rho = 0.634, P  < 0.001), and pain catastrophizing (rho = 0.456, P  < 0.01), but not with intensity of pain, duration of pain, or pain disability.

Conclusions

In CRPS patients, NLS could be a result of somatization, depression, anxiety, and depersonalization, but probably not of pain. Whether these associations are causative must be clarified in longitudinal psychological studies.

Resting Brain Activity Related to Dispositional Mindfulness: a PET Study

Mindfulness denotes a state of consciousness characterized by receptive attention to and awareness of present events and experiences. As a personality trait, it constitutes the ability to become aware of mental activities such as sensations, images, feelings, and thoughts, and to disengage from judgment, conditioned emotions, and their cognitive processing or automatic inhibition. Default brain activity reflects the stream of consciousness and sense of self at rest. Analysis of brain activity at rest in persons with mindfulness propensity may help to elucidate the neurophysiological basis of this important mental trait. The sample consisted of 32 persons-23 with mental disorders and 9 healthy controls. Dispositional mindfulness (DM) was operationalized by Mindful Attention Awareness Scale (MAAS). Brain activity at rest with eyes closed was assessed by fluorodeoxyglucose positron emission tomography (F-18-FDG PET). After adjustment for depression, anxiety, age and years of education, resting glucose metabolism in superior parietal lobule and left precuneus/Brodmann area (BA) 7 was positively associated with DM. Activity of the left inferior frontal orbital gyrus (BA 47) and bilateral anterior thalamus were inversely associated with DM. DM appears to be associated with increased metabolic activity in some core area of the default mode network (DMN) and areas connected to the DMN, such as BA 7, hosting sense of self functions. Hypometabolism on the other hand was found in some nodes connected to the DMN, such as left inferior frontal orbital gyrus and bilateral thalamus, commonly related to functions of memory retrieval, decision making, or outward attention.

Cardiac modulation of startle is altered in depersonalization-/derealization disorder: Evidence for impaired brainstem representation of baro-afferent neural traffic

Patients with depersonalization-/derealization disorder (DPD) show altered heartbeat-evoked brain potentials, which are considered psychophysiological indicators of cortical representation of visceral-afferent neural signals. The aim of the current investigation was to clarify whether the impaired CNS representation of visceral-afferent neural signals in DPD is restricted to the cortical level or is also present in sub-cortical structures. We used cardiac modulation of startle (CMS) to assess baro-afferent signal transmission at brainstem level in 22 DPD and 23 healthy control individuals. The CMS paradigm involved acoustic startle stimuli (105dB(A), 50ms) elicited 0, 100, 200, 300, 400 and 500ms after a cardiac R-wave. In healthy control individuals, we observed lower startle responses at 100 and 300ms than at 0 and 400ms after an R-wave. In DPD patients, no effect of the cardiac cycle on startle response magnitude was found. We conclude that the representation of visceral-afferent neural signals at brainstem level may be deficient in DPD. This effect may be due to increased peripheral sympathetic tone or to dysregulated signal processing at brainstem level.

A case series of 223 patients with depersonalization-derealization syndrome

BACKGROUND

Depersonalization-derealization syndrome (DDS) is an underdiagnosed and underresearched clinical phenomenon. In Germany, its administrative prevalence is far below the threshold for orphan diseases, although according to epidemiological surveys the diagnosis should be comparable frequent as anorexia nervosa for instance. Against this background, we carried out a large comprehensive survey of a DDS series in a tertiary mental health center with a specialized depersonalization-derealization clinic. To reveal differential characteristics, we compared the DDS patients, who consulted the specialized depersonalization-derealization clinic, with a group of patients with depressive disorders without comorbid DDS from the regular outpatient clinic of the mental health center.

METHODS

The sample comprised 223 patients with a diagnosis of depersonalization-derealization-syndrome and 1129 patients with a depressive disorder but without a comorbid diagnosis of DDS. DDS patients were described and compared with depressive outpatients in terms of sociodemographic characteristics, treatment history, treatment wishes, clinical symptomatology, prevailing psychosocial stressors, family history of common mental disorders and history of childhood trauma.

RESULTS

Despite the high comorbidity of DDS patients with depressive disorders and comparable burden with symptoms of depression and anxiety, the clinical picture and course of both patient groups differed strongly. DDS patients were younger, had a significant preponderance of male sex, longer disease duration and an earlier age of onset, a higher education but were more often unemployed. They tended to show more severe functional impairment. They had higher rates of previous or current mental health care utilization. Nearly all DDS patients endorsed the wish for a symptom specific counseling and 70.7 % were interested in the internet-based treatment of their problems. DDS patients had lower levels of self-rated traumatic childhood experiences and current psychosocial stressors. However, they reported a family history of anxiety disorders more often.

CONCLUSION

In consideration of the selection bias of this study, this case series supports the view that the course of the DDS tends to be long-lasting. DDS patients are severely impaired, utilizing mental health care to a high degree, which nevertheless might not meet their treatment needs, as patients strongly opt for obtaining disorder specific counseling. In view of the size of the problem, more research on the disorder, its course and its optimal treatment is urgently required.

Developing research priorities for palliative care of people with intellectual disabilities in Europe: a consultation process using nominal group technique

Background

Empirical knowledge around palliative care provision and needs of people with intellectual disabilities is extremely limited, as is the availability of research resources, including expertise and funding. This paper describes a consultation process that sought to develop an agenda for research priorities for palliative care of people with intellectual disabilities in Europe.

Methods

A two-day workshop was convened, attended by 16 academics and clinicians in the field of palliative care and intellectual disability from six European countries. The first day consisted of round-table presentations and discussions about the current state of the art, research challenges and knowledge gaps. The second day was focused on developing consensus research priorities with 12 of the workshop participants using nominal group technique, a structured method which involved generating a list of research priorities and ranking them in order of importance.

Results

A total of 40 research priorities were proposed and collapsed into eleven research themes. The four most important research themes were: investigating issues around end of life decision making; mapping the scale and scope of the issue; investigating the quality of palliative care for people with intellectual disabilities, including the challenges in achieving best practice; and developing outcome measures and instruments for palliative care of people with intellectual disabilities.

Conclusions

The proposal of four major priority areas and a range of minor themes for future research in intellectual disability, death, dying and palliative care will help researchers to focus limited resources and research expertise on areas where it is most needed and support the building of collaborations. The next steps are to cross-validate these research priorities with people with intellectual disabilities, carers, clinicians, researchers and other stakeholders across Europe; to validate them with local and national policy makers to determine how they could best be incorporated in policy and programmes; and to translate them into actual research studies by setting up European collaborations for specific studies that require such collaboration, develop research proposals and attract research funding.

Is that me in the mirror? Depersonalisation modulates tactile mirroring mechanisms

Our sense of self is thought to develop through sensory-motor contingencies provided, not only by observing one's own body, but also by mirroring interactions with others. This suggests that there is a strong link between mirroring mechanisms and the bodily self. The present study tested whether this link is expressed at early, implicit stages of the mirroring process or at later, more cognitive stages. We also provide, to the best of our knowledge, the first demonstration of how inter-individual differences in our sense of bodily self may affect mirroring mechanisms. We used somatosensory event-related potentials (SEPs) to investigate the temporal dynamics of mirroring highly self-related information (viewed touch on one's own face) compared to other-related information (viewed touch on a stranger's face), in individuals with low and high levels of depersonalisation, a mental condition characterised by feeling detached or estranged from one's self and body. For the low-depersonalisation group, mirroring for self-related events (P45) preceded mirroring for other-related events (N80). At later stages (P200), mirroring was stronger for other-related than self-related events. This shows that early, implicit and later, more cognitive processes play different relative roles in mirroring self- and other-related bodily events. Critically, mirroring differed in the high-depersonalisation group, specifically for self-related events. An absence of early, implicit mirroring for self-related events over P45 suggests that the associated processes may be the neural correlates of the disembodiment experienced in depersonalisation. A lack of differential mirroring for self- and other-related events over P200 may reflect compensatory mechanisms that redress deficiencies in mirroring at earlier stages, which may break down to give rise to symptoms of depersonalisation. Alternatively, or in addition, they may represent an attenuation of processes related to self-other distinction. Our study thus shows that mirroring, especially for events on one's own face, can be strongly affected by how connected the observer feels to their own bodily self.

[Improvement of emergency physician education through simulator training. Consideration on the basis of the model project "NASimSaar25"]

BACKGROUND

Prehospital emergency medicine is a challenge for trainee emergency physicians. Rare injuries and diseases as well as patients in extreme age groups can unexpectedly face emergency physicians. In the regulations on medical education the German Medical Association requires participation in 50 emergency missions under the supervision of an experienced emergency physician. This needs to be improved because on-the-job training does not generally represent the whole spectrum of emergency medicine and a good and structured training under on call conditions is nearly impossible.

AIM

The subject of the model project described was whether practical training for emergency physicians can be achieved by participation in simulation training instead of real emergency situations.

MATERIAL AND METHODS

After modification of the Saarland regulations on medical education it was possible to replace up to 25 participations in emergency missions by simulation training. The concept of the course NASimSaar25 requires participants to complete 25 simulator cases in 3 days in small training groups. Emergency situations from all medical disciplines need to be treated. A special focus is on the treatment of life-threatening and rare diseases and injuries. Modern simulators and actors are used. The debriefings are conducted by experienced tutors based on approved principles. Medical contents, learning targets from the field of crew resource management (CRM) and soft skills are discussed in these debriefings.

RESULTS

Education in the field of emergency medicine can be improved by simulator-based learning and training. However, practical work under a tutor in real and clinical experience cannot be completely replaced by simulation. Simulator training can only be successful if theoretical knowledge has already been acquired.

CONCLUSION

A simulator-based course concept can result in an improvement of emergency medical education. The model project NASimSaar25 was well received by the target audience and mostly very well evaluated in terms of learning and reality. If this project becomes established the demand on simulation-based training will increase. The training should achieve a consistent standard of quality.

Prevalence and correlates of depersonalization in students aged 12-18 years in Germany

BACKGROUND

Depersonalization (DP) involves unpleasant experiences of detachment from one's sense of self or unreality in the environment. DP may occur in a broad range of conditions, among healthy persons due to sleep loss, drug induced, secondary to anxiety disorders or primary in depersonalization disorder. Although DP has an early age of onset, little is known about the prevalence and correlates of DP among adolescents.

METHODS

Between January and June 2011, we conducted a questionnaire-based representative survey of pupils aged 12-18 years in the federal state Rhineland-Palatinate of Germany. The final sample comprised 3,809 pupils. We analyzed the prevalence of depersonalization and its correlates regarding sociodemographic characteristics, substance abuse, global mental distress and resilience factors.

RESULTS

One-third of the sample showed severe global mental distress, and 11.9 % were in the range of clinically significant depersonalization. Depersonalized students were less often living with both parents (67.3 vs. 75.7 %), came more often from an disadvantaged socioeconomic background, had a very severe level of global mental distress (comparable to psychiatric inpatients), were more often smoking and abusing cannabis and they suffered from specific impairments regarding social insecurity, global self-efficacy and active coping abilities.

CONCLUSIONS

Experiences of depersonalization were very common among adolescents and may indicate an increased risk for poor academic achievement and mental health in the long term. Prospective studies are needed to investigate the course and clinical relevance of depersonalization for the development of the adolescents.

The Tyrosine Kinase c-Abl Promotes Homeodomain-interacting Protein Kinase 2 (HIPK2) Accumulation and Activation in Response to DNA Damage

The non-receptor tyrosine kinase c-Abl is activated in response to DNA damage and induces p73-dependent apoptosis. Here, we investigated c-Abl regulation of the homeodomain-interacting protein kinase 2 (HIPK2), an important regulator of p53-dependent apoptosis. c-Abl phosphorylated HIPK2 at several sites, and phosphorylation by c-Abl protected HIPK2 from degradation mediated by the ubiquitin E3 ligase Siah-1. c-Abl and HIPK2 synergized in activating p53 on apoptotic promoters in a reporter assay, and c-Abl was required for endogenous HIPK2 accumulation and phosphorylation of p53 at Ser(46) in response to DNA damage by γ- and UV radiation. Accumulation of HIPK2 in nuclear speckles and association with promyelocytic leukemia protein (PML) in response to DNA damage were also dependent on c-Abl activity. At high cell density, the Hippo pathway inhibits DNA damage-induced c-Abl activation. Under this condition, DNA damage-induced HIPK2 accumulation, phosphorylation of p53 at Ser(46), and apoptosis were attenuated. These data demonstrate a new mechanism for the induction of DNA damage-induced apoptosis by c-Abl and illustrate network interactions between serine/threonine and tyrosine kinases that dictate cell fate.

Randomised clinical trial: the 5-HT4 agonist revexepride in patients with gastro-oesophageal reflux disease who have persistent symptoms despite PPI therapy

BACKGROUND

A substantial proportion of patients with gastro-oesophageal reflux disease (GERD) have only a partial response to proton pump inhibitor (PPI) therapy. Prokinetic drugs may improve reflux symptoms by enhancing oesophageal motility and gastric emptying.

AIM

To evaluate the effect of revexepride, a novel prokinetic 5-hydroxytryptamine type 4 (5-HT4 ) receptor agonist, compared with placebo, in patients with GERD who have a partial response to PPIs.

METHODS

A phase 2b, double-blind, parallel-group study was conducted, in which patients were randomised to one of three revexepride treatment groups (0.1, 0.5 and 2.0 mg three times daily) or placebo (1:1:1:1 ratio). Daily e-diary data captured patients' symptoms over an 8-week treatment period. The primary efficacy outcome was the weekly percentage of regurgitation-free days in the second half of the study (weeks 5-8).

RESULTS

In total, 480 patients were randomised and 477 received treatment (mean age 47.9 years; 61% women). The mean percentage of regurgitation-free days increased from baseline (range, 15.0-18.8%) to week 8 (62.3-70.5%) in all four study arms; however, there were no statistically significant differences in this change between placebo and the three treatment arms. No dose-dependent relationship in treatment effect was observed for any of the study endpoints. The incidence of treatment-emergent adverse events (TEAEs) was revexepride dose-dependent. Only one serious TEAE occurred and none resulted in death.

CONCLUSIONS

Revexepride was no more effective than placebo in controlling regurgitation in patients with GERD symptoms partially responsive to PPIs. Revexepride was well tolerated. ClinicalTrials.gov Identifier: NCT01472939.

Altered orientation of spatial attention in depersonalization disorder

Difficulties with concentration are frequent complaints of patients with depersonalization disorder (DPD). Standard neuropsychological tests suggested alterations of the attentional and perceptual systems. To investigate this, the well-validated Spatial Cueing paradigm was used with two different tasks, consisting either in the detection or in the discrimination of visual stimuli. At the start of each trial a cue indicated either the correct (valid) or the incorrect (invalid) position of the upcoming stimulus or was uninformative (neutral). Only under the condition of increased task difficulty (discrimination task) differences between DPD patients and controls were observed. DPD patients showed a smaller total attention directing effect (RT in valid vs. invalid trials) compared to healthy controls only in the discrimination condition. RT costs (i.e., prolonged RT in neutral vs. invalid trials) mainly accounted for this difference. These results indicate that DPD is associated with altered attentional mechanisms, especially with a stronger responsiveness to unexpected events. From an evolutionary perspective this may be advantageous in a dangerous environment, in daily life it may be experienced as high distractibility.

NADH binds and stabilizes the 26S proteasomes independent of ATP

The 26S proteasome is the end point of the ubiquitin- and ATP-dependent degradation pathway. The 26S proteasome complex (26S PC) integrity and function has been shown to be highly dependent on ATP and its homolog nucleotides. We report here that the redox molecule NADH binds the 26S PC and is sufficient in maintaining 26S PC integrity even in the absence of ATP. Five of the 19S proteasome complex subunits contain a putative NADH binding motif (GxGxxG) including the AAA-ATPase subunit, Psmc1 (Rpt2). We demonstrate that recombinant Psmc1 binds NADH via the GxGxxG motif. Introducing the ΔGxGxxG Psmc1 mutant into cells results in reduced NADH-stabilized 26S proteasomes and decreased viability following redox stress induced by the mitochondrial inhibitor rotenone. The newly identified NADH binding of 26S proteasomes advances our understanding of the molecular mechanisms of protein degradation and highlights a new link between protein homeostasis and the cellular metabolic/redox state.

Striking discrepancy of anomalous body experiences with normal interoceptive accuracy in depersonalization-derealization disorder

Background

Disembodiment is a core feature of depersonalization disorder (DPD). Given the narratives of DPD patients about their disembodiment and emotional numbing and neurobiological findings of an inhibition of insular activity, DPD may be considered as a mental disorder with specific impairments of interoceptive awareness and body perception.

Methods

We investigated cardioceptive accuracy (CA) of DPD patients (n = 24) as compared to healthy controls (n = 26) with two different heartbeat detection tasks (“Schandry heartbeat counting task” and “Whitehead heartbeat discrimination task”). Self-rated clearness of body perception was measured by questionnaire.

Results

Contrary to our hypothesis, DPD patients performed similarly to healthy controls on the two different heartbeat detection tasks, and they had equal scores regarding their self-rated clearness of body perception. There was no correlation of the severity of “anomalous body experiences” and depersonalization with measures of interoceptive accuracy. Only among healthy controls CA in the Schandry task was positively correlated with self-rated clearness of body perception. Depersonalization was unrelated to severity of depression or anxiety, while depression and anxiety were highly correlated. Anxiety and depression did not modify the associations of depersonalization with interoceptive accuracy.

Conclusions

Our main findings highlight a striking discrepancy of normal interoception with overwhelming experiences of disembodiment in DPD. This may reflect difficulties of DPD patients to integrate their visceral and bodily perceptions into a sense of their selves. This problem may be considered an important target for psychotherapeutic treatment approaches.

Comparison of the cellular composition of two different chondrocyte-seeded biomaterials and the results of their transplantation in humans

Our study compares the histological and immunohistochemical cellular composition of two different chondrocyte-seeded biomaterials and the results of their transplantation. Our study cohort included 21 patients, comprising 19 men and two women with a mean age of 32 years, who were affected by single chondral lesions of the femoral condyles. These patients were enrolled in our study and treated with arthroscopic implantation of the tissue Hyalograft C and/or Brno culture. Brno culture bioengineered with a fibrin-based scaffold contains round cells showing features of differentiated chondrocytes expressing S-100 protein and α-smooth muscle actin. In contrast, in the case of Hyalograft C, the scaffold was made up of a fibrillar network composed of biomaterial fibres of the esters of hyaluronic acid and cells resembling fibroblasts and myofibroblasts and expressing only α-smooth muscle actin. The average size of the defects was 2.5 cm2. Patients were evaluated using the standardized guidelines of the International Knee Documentation Committee. During the comparison of bioptic samples obtained from both patient cohorts, we did not observe any important differences in the histological makeup of the newly formed cartilage. The histological analysis of these two groups of homogeneous patients shows that this bioengineered approach, under proper indications, may offer favourable and stable clinical results over time, in spite of the different matrix and cellular composition of the two transplants used.

Depersonalization disorder: disconnection of cognitive evaluation from autonomic responses to emotional stimuli

BACKGROUND

Patients with depersonalization disorder (DPD) typically complain about emotional detachment. Previous studies found reduced autonomic responsiveness to emotional stimuli for DPD patients as compared to patients with anxiety disorders. We aimed to investigate autonomic responsiveness to emotional auditory stimuli of DPD patients as compared to patient controls. Furthermore, we examined the modulatory effect of mindful breathing on these responses as well as on depersonalization intensity.

METHODS

22 DPD patients and 15 patient controls balanced for severity of depression and anxiety, age, sex and education, were compared regarding 1) electrodermal and heart rate data during a resting period, and 2) autonomic responses and cognitive appraisal of standardized acoustic affective stimuli in two conditions (normal listening and mindful breathing).

RESULTS

DPD patients rated the emotional sounds as significantly more neutral as compared to patient controls and standardized norm ratings. At the same time, however, they responded more strongly to acoustic emotional stimuli and their electrodermal response pattern was more modulated by valence and arousal as compared to patient controls. Mindful breathing reduced severity of depersonalization in DPD patients and increased the arousal modulation of electrodermal responses in the whole sample. Finally, DPD patients showed an increased electrodermal lability in the rest period as compared to patient controls.

CONCLUSIONS

These findings demonstrated that the cognitive evaluation of emotional sounds in DPD patients is disconnected from their autonomic responses to those emotional stimuli. The increased electrodermal lability in DPD may reflect increased introversion and cognitive control of emotional impulses. The findings have important psychotherapeutic implications.

Meta-analysis: rapid infliximab infusions are safe

BACKGROUND

Infliximab is typically administered intravenously via 2- to 3-h duration infusions. Infusions are time-consuming and costly. Shorter duration infusions are administered at some centres. Limited safety data are available on shorter duration infusions.

AIM

To determine risk of infusion reaction associated with standard 2- to 3-h infusions vs. rapid infusions in patients receiving infliximab therapy for inflammatory bowel disease (IBD), rheumatoid arthritis, spondylarthopathy and psoriatic disease.

METHODS

MEDLINE, Embase, and Web of Science were searched. Inclusion required human subjects, documentation of number of standard and rapid infliximab infusions and number of incident infusion reactions. Studies of overlapping populations were excluded. Three reviewers independently extracted data. Study quality was assessed. Relative risk (RR) was pooled using random effects models.

RESULTS

We identified 10 studies comprising 13 147 standard 2- to 3-h and 8497 ≤ 1-h infliximab infusions. Nine studies reported the risk of infusion reaction in standard vs. 1-h infusions, demonstrating decreased RR of infusion reaction with 1-h vs. standard infusions (0.9% vs. 2.2% of infusions; RR = 0.48, P = 0.009). Seven studies limited to IBD also demonstrated decreased risk of reaction (RR = 0.49, P = 0.002). Other comparisons demonstrated no difference in RR of reaction, including concomitant medication use (P = 0.30) or analysis limited to high and medium quality studies (P = 0.07).

CONCLUSIONS

Rapid infliximab infusions of ≤1-h duration are not associated with increased risk of infusion reaction when compared to standard 2- to 3-h infusions in selected patients who previously tolerated three to four standard infusions. One-hour infusions will conserve health care resources and may lead to improved adherence and quality of life in patients receiving infliximab.

The decommissioning of light water reactors – experience

More than ten nuclear power plants in Germany have been decommissioned or are under dismantling. Objectives, strategies, preparatory work, licensing, technical dismantling and safety considerations are explained from the utility point of view, using the Stade (KKS) decommissioning as an example. Challenges with respect to characterisation, logistics and economy are discussed.

Object-guided spatial selection in touch without concurrent changes in the perceived location of the hands

In an endogenous cueing paradigm with central visual cues, observers made speeded responses to tactile targets at the hands, which were either close together or far apart, and holding either two separate objects or one common object between them. When the hands were far apart, the response time costs associated with attending to the wrong hand were reduced when attention had to be shifted along one object jointly held by both hands compared to when it was shifted over the same distance but across separate objects. Similar reductions in attentional costs were observed when the hands were placed closer together, suggesting that processing at one hand is less prioritized over that at another when the hands can be "grouped" by virtue of arising from the same spatial location or from the same object. Probes of perceived hand locations throughout the task showed that holding a common object decreased attentional separability without decreasing the perceived separation between the hands. Our findings suggest that tactile events at the hands may be represented in a spatial framework that flexibly adapts to (object-guided) attentional demands, while their relative coordinates are simultaneously preserved.

Clinical benefits with oseltamivir in treating influenza in adult populations : results of a pooled and subgroup analysis

BACKGROUND

Influenza is a potentially life-threatening illness that affects approximately 10% of the population annually, with resulting personal misery and societal disruption. Oseltamivir is a novel influenza treatment that has been extensively investigated. We describe a series of retrospective analyses investigating various measures of clinical efficacy across different populations of influenza-infected patients enrolled in studies of oseltamivir (Tamiflu((R))) that were conducted within the clinical development programme.

METHODS

Adolescents and adults (13-97 years, n = 4015) presenting within 36 hours of onset of influenza symptoms were randomised to receive oseltamivir 75mg or placebo twice daily for 5 days during local influenza outbreaks. Of these patients, 2413 had laboratory-confirmed influenza and are included in the analysis. Approximately 30% (n = 739) of patients were 'high risk'; 20% were healthy elderly subjects (n = 488) and 10% (n = 251) were patients with chronic respiratory and/or cardiac conditions. The primary endpoint was time to alleviation of a seven-symptom cluster in influenza-infected patients. Supplementary analyses were conducted using a variety of illness definitions and symptom clusters to investigate the sensitivity of the assessment of overall efficacy to differing disease definitions and also to explore efficacy in important subpopulations.

RESULTS

A total of 2413 patients had confirmed influenza infection (placebo: n = 1063; oseltamivir: n = 1350). Across all populations, the time to alleviation of illness was reduced by 19% (median duration 100.6 hours [95% CI 94.8-104.7]) compared with placebo (124.5 hours [95% CI 117.7-132.3], p < 0.0001). Oseltamivir recipients returned to normal health status, regained ability to perform usual activities and regained normal sleep patterns significantly faster than placebo recipients. The median duration of troublesome influenza symptoms was significantly reduced by oseltamivir treatment, e.g. fatigue by 29% and myalgia by 26% (both p < 0.0001). After 48 hours of treatment, 57% more placebo than oseltamivir recipients remained febrile, despite greater use of acetaminophen by placebo recipients. In addition, the median duration of acute febrile illness was significantly shortened by oseltamivir treatment compared with placebo in patients with cardiac disease (44.0 hours vs 64.7 hours, p = 0.026) or chronic obstructive airways disease (37.9 hours vs 53.8 hours, p = 0.004).Efficacy was similar among influenza A- and influenza B-infected patients. Oseltamivir was well tolerated, with transient gastrointestinal effects (observed in one in seven oseltamivir-treated patients compared with one in 12 patients on placebo) that only rarely resulted in study discontinuation.

CONCLUSIONS

Oral oseltamivir is a well tolerated and effective treatment for influenza in adolescents and adults, including the elderly and patients with chronic cardiac and/or respiratory disease.