Electromechanical vortex filaments during cardiac fibrillation.

The self-organized dynamics of vortex-like rotating waves, which are also known as scroll waves, are the basis of the formation of complex spatiotemporal patterns in many excitable chemical and biological systems. In the heart, filament-like phase singularities that are associated with three-dimensional scroll waves are considered to be the organizing centres of life-threatening cardiac arrhythmias. The mechanisms that underlie the onset, maintenance and control of electromechanical turbulence in the heart are inherently three-dimensional phenomena. However, it has not previously been possible to visualize the three-dimensional spatiotemporal dynamics of scroll waves inside cardiac tissues. Here we show that three-dimensional mechanical scroll waves and filament-like phase singularities can be observed deep inside the contracting heart wall using high-resolution four-dimensional ultrasound-based strain imaging. We found that mechanical phase singularities co-exist with electrical phase singularities during cardiac fibrillation. We investigated the dynamics of electrical and mechanical phase singularities by simultaneously measuring the membrane potential, intracellular calcium concentration and mechanical contractions of the heart. We show that cardiac fibrillation can be characterized using the three-dimensional spatiotemporal dynamics of mechanical phase singularities, which arise inside the fibrillating contracting ventricular wall. We demonstrate that electrical and mechanical phase singularities show complex interactions and we characterize their dynamics in terms of trajectories, topological charge and lifetime. We anticipate that our findings will provide novel perspectives for non-invasive diagnostic imaging and therapeutic applications.

Efficient termination of cardiac arrhythmias using optogenetic resonant feedback pacing.

Malignant cardiac tachyarrhythmias are associated with complex spatiotemporal excitation of the heart. The termination of these life-threatening arrhythmias requires high-energy electrical shocks that have significant side effects, including tissue damage, excruciating pain, and worsening prognosis. This significant medical need has motivated the search for alternative approaches that mitigate the side effects, based on a comprehensive understanding of the nonlinear dynamics of the heart. Cardiac optogenetics enables the manipulation of cellular function using light, enhancing our understanding of nonlinear cardiac function and control. Here, we investigate the efficacy of optically resonant feedback pacing (ORFP) to terminate ventricular tachyarrhythmias using numerical simulations and experiments in transgenic Langendorff-perfused mouse hearts. We show that ORFP outperforms the termination efficacy of the optical single-pulse (OSP) approach. When using ORFP, the total energy required for arrhythmia termination, i.e., the energy summed over all pulses in the sequence, is 1 mJ. With a success rate of 50%, the energy per pulse is 40 times lower than with OSP with a pulse duration of 10 ms. We demonstrate that even at light intensities below the excitation threshold, ORFP enables the termination of arrhythmias by spatiotemporal modulation of excitability inducing spiral wave drift.

Ångstrom-Depth Resolution with Chemical Specificity at the Liquid-Vapor Interface.

The determination of depth profiles across interfaces is of primary importance in many scientific and technological areas. Photoemission spectroscopy is in principle well suited for this purpose, yet a quantitative implementation for investigations of liquid-vapor interfaces is hindered by the lack of understanding of electron-scattering processes in liquids. Previous studies have shown, however, that core-level photoelectron angular distributions (PADs) are altered by depth-dependent elastic electron scattering and can, thus, reveal information on the depth distribution of species across the interface. Here, we explore this concept further and show that the experimental anisotropy parameter characterizing the PAD scales linearly with the average distance of atoms along the surface normal obtained by molecular dynamics simulations. This behavior can be accounted for in the low-collision-number regime. We also show that results for different atomic species can be compared on the same length scale. We demonstrate that atoms separated by about 1 Å along the surface normal can be clearly distinguished with this method, achieving excellent depth resolution.

The effectiveness of two silicone dressings for sacral and heel pressure ulcer prevention compared with no dressings in high-risk intensive care unit patients: a randomized controlled parallel-group trial.

BACKGROUND: There is a high incidence of pressure ulcers in high-risk settings such as intensive care. There is emerging evidence that the application of dressings to pressure ulcer predilection areas (sacrum and heels) improves prevention strategies. OBJECTIVES: To determine whether preventive dressings, applied to the sacrum and heels of high-risk patients in intensive care units, in addition to standard prevention, reduces the incidence of pressure ulcers. METHODS: Between June 2015 and July 2018, a randomized, controlled, two-arm, superiority pragmatic study was performed with a concealed 1 : 1 allocation to the intervention and control group. Patients assigned to the intervention group had dressings applied to the sacrum and heels. RESULTS: In total, 7575 patients were screened for eligibility and 475 patients were included and allocated to both groups. Finally, 212 patients in the intervention group and 210 in the control group were analysed. The mean age was 63·5 years and the majority of patients were male (65·4%). The cumulative pressure ulcer incidence category II and above was 2·8% in the intervention, and 10·5% in the control group (P = 0·001). Compared with the control group, the relative risk in the intervention group was 0·26 [95% confidence interval (CI) 0·11-0·62] and the absolute risk reduction was 0·08 (95% CI 0·03-0·13). CONCLUSIONS: The results indicate that the application of dressings, in addition to standard prevention, in high-risk intensive care unit patients is effective in preventing pressure ulcers at the heels and sacrum. What's already known about this topic? Pressure ulcers are severe soft tissue injuries and wounds, which occur worldwide in all healthcare settings. Despite preventive interventions, pressure ulcers still develop. There is emerging evidence that dressings help to prevent pressure ulcers. What does this study add? The incidence of pressure ulcers in intensive care units among high-risk patients remains high. The application of dressings to the sacrum and heels, in addition to standard preventive measures, reduces the relative and absolute risks for the development of pressure ulcers. The application of preventive dressings at the heels and sacrum seems to be feasible in intensive care settings.

Photoisomerization dynamics of trans-trans, cis-trans, and cis-cis diphenylbutadiene from broadband transient absorption spectroscopy and calculations.

The photoisomerization path and dynamics of trans-trans (ttD), cis-trans (ctD), and cis-cis (ccD) 1,4-diphenyl-1,3-butadiene (DPB) in solution are studied with broadband transient absorption (TA) spectroscopy and quantum chemical calculations. For ttD in n-hexane, 2-photon-excited TA spectra indicate that the 2Ag state is located above 1-photon allowed 1Bu (S1) by ∼1000 cm-1. Following S0 → S1 optical excitation, the isomerization occurs via torsion about a butadiene double bond to perpendicular molecular configuration P. The P-state is detected in ccD with an excited-state absorption band at 390 nm. This P-band develops during S1 → P half-torsion with time of 0.15 ps, followed further by P → S0 half-torsion and simultaneous decay with 1.6 ps in acetonitrile and 5 ps in n-hexane. In addition, two oscillation cycles between P and S1 population are observed before equilibration in n-hexane. For ctD, an indication of rising and decaying P is found in acetonitrile. The vast majority of ctD species photoisomerizes to ttD and not to ccD, in agreement a with calculated low torsional barrier about the cis double bond and high barrier about the trans double bond. Photoisomerization yield Y and time τi depend drastically on the solvent polarity. Thus, in n-hexane, the isomerization ttD → ctD has yield Ytt,ct = 0.1 and time τi = 829 ps, while in acetonitrile, Ytt,ct = 0.4 and τi = 27 ps. The 30-fold acceleration of the isomerization in acetonitrile clearly reflects a highly polar character of P, consistent with a dipole moment µP > 9.6 D. The results for DPB are discussed in comparison to stilbene.

Interface superconductor with gap behaviour like a high-temperature superconductor.

The physics of the superconducting state in two-dimensional (2D) electron systems is relevant to understanding the high-transition-temperature copper oxide superconductors and for the development of future superconductors based on interface electron systems. But it is not yet understood how fundamental superconducting parameters, such as the spectral density of states, change when these superconducting electron systems are depleted of charge carriers. Here we use tunnel spectroscopy with planar junctions to measure the behaviour of the electronic spectral density of states as a function of carrier density, clarifying this issue experimentally. We chose the conducting LaAlO3-SrTiO3 interface as the 2D superconductor, because this electron system can be tuned continuously with an electric gate field. We observed an energy gap of the order of 40 microelectronvolts in the density of states, whose shape is well described by the Bardeen-Cooper-Schrieffer superconducting gap function. In contrast to the dome-shaped dependence of the critical temperature, the gap increases with charge carrier depletion in both the underdoped region and the overdoped region. These results are analogous to the pseudogap behaviour of the high-transition-temperature copper oxide superconductors and imply that the smooth continuation of the superconducting gap into pseudogap-like behaviour could be a general property of 2D superconductivity.

Effects of a dynamic core stability program on the biomechanics of cutting maneuvers: A randomized controlled trial.

Deficits in trunk control predict ACL injuries which frequently occur during high-risk activities such as cutting. However, no existing trunk control/core stability program has been found to positively affect trunk kinematics during cutting activities. This study investigated the effectiveness of a 6-week dynamic core stability program (DCS) on the biomechanics of anticipated and unanticipated side and crossover cutting maneuvers. Thirty-one male, varsity footballers participated in this randomized controlled trial. Three-dimensional trunk and lower limb biomechanics were captured in a motion analysis laboratory during the weight acceptance phase of anticipated and unanticipated side and crossover cutting maneuvers at baseline and 6-week follow-up. The DCS group performed a DCS program three times weekly for 6 weeks in a university rehabilitation room. Both the DCS and control groups concurrently completed their regular practice and match play. Statistical parametric mapping and repeated measures analysis of variance were used to determine any group (DCS vs control) by time (pre vs post) interactions. The DCS resulted in greater internal hip extensor (P=.017, η2 =0.079), smaller internal knee valgus (P=.026, η2 =0.076), and smaller internal knee external rotator moments (P=.041, η2 =0.066) during anticipated side cutting compared with the control group. It also led to reduced posterior ground reaction forces for all cutting activities (P=.015-.030, η2 =0.074-0.105). A 6-week DCS program did not affect trunk kinematics, but it did reduce a small number of biomechanical risk factors for ACL injury, predominantly during anticipated side cutting. A DCS program could play a role in multimodal ACL injury prevention programs.

Is stiffness related to athletic groin pain?

Athletic groin pain (AGP) is a common injury prevalent in field sports. One biomechanical measure that may be of importance for injury risk is stiffness. To date, [corrected] however, stiffness has not been examined in AGP. The primary aim was to determine whether AGP affects vertical and joint stiffness and if so, whether successful rehabilitation is associated with a change in stiffness. Sixty-five male patients with AGP and fifty male controls were recruited to this study. Assessment included a biomechanical examination of stiffness during a lateral hurdle hop test. Subjects with AGP were tested pre- and post-rehabilitation, while controls were tested once. AGP subjects were cleared for return to play in a median time of 9.14 weeks (5.14-29.0). Stiffness was significantly different at pre-rehabilitation in comparison with controls for three [corrected] of the ten stiffness values examined: ankle plantar flexor, knee extensor, hip abductor, and vertical stiffness (P <  .05, D = 0.38-0.81). [corrected]. Despite clearance for return to play, of these four variables, only hip abductor stiffness changed significantly from pre- to post-rehabilitation (P = .05, D = 0.36) [corrected] to become non-significantly different to the uninjured group (P = .23, D = 0.23). [corrected]. These findings suggest that hip abductor stiffness may represent a target for AGP rehabilitation. Conversely, given the clearance for return to play, the lower sagittal plane and vertical stiffness in the AGP group in comparison with the uninjured controls likely represents either a compensatory mechanism to reduce the risk of further injury or a consequence of neuromuscular detraining.

[Keratoplasty in Children and Adolescents]. / Keratoplastiken im Kindes- und Jugendalter.

BACKGROUND: The conditions for long-term graft survival in infants and children are unfavorable, due to the different immunological features, the impaired clinical examination and the reduced compliance and treatment adherence. However, penetrating keratoplasty is often the only option to prevent amblyopia and there may be no alternative. We examined the different indications, graft survival and complications in two specialised centres. MATERIAL AND METHODS: We identified all patients who were under the age of 18 years at the time of their penetrating keratoplasty. We then assessed the electronic file on indications, graft failure, visual acuity, enucleation and further complications. RESULTS: A total of 104 eyes of 95 patients (54 % female) were identified. Median age at the time of surgery was 14 years (quartiles 8 and 16 years). Median follow-up was 2.7 years. The following indications were identified: keratoconus (39 %), penetrating injury (18 %), non-herpetic corneal scars (12 %), herpetic corneal scars (6 %), sclerocornea (3 %), chemical burn (3 %) and miscellaneous indications (19 %). Clear graft survival according to the Kaplan-Meier method ranged from 100 % (keratoconus) to 35 % (sclerocornea). Enucleation was only necessary in patients with penetrating injuries (n = 2). Kaplan-Meier analysis estimated the failure of all grafts after one year in infants. In older patients, 90 % of grafts were still clear at that time. CONCLUSION: Prognosis of penetrating keratoplasty in children is related to the indication, and therefore the underlying disease, as well as the patients' age. In particular, infants exhibited poor prognosis, with only a very short period of clear graft survival. In indications, keratoconus showed the best prognosis, whereas sclerocornea and penetrating injuries had the worst prognosis.

Consequences of changes in the ZnO trap distribution on the performance of dye-sensitized solar cells.

The well-established indoline dye D149 and three indoline dyes with improved binding stability (DN91, DN216 and DN285) were used as sensitizers for electrodeposited porous ZnO and studied in dye-sensitized solar cells and showed very similar cell characteristics. After storage of the cells in the dark for four weeks, an increase in short-circuit current density was observed. Electrochemical impedance spectroscopy served to detect a shift of the conduction band edge energy to lower energies and, hence, an increased injection efficiency of electrons from the excited state of the sensitizer to the ZnO conduction band is detected as the main cause of this change. Additional photoelectrochemical experiments at different illumination intensities, intensity modulated photocurrent and photovoltage spectroscopy (IMPS and IMVS), transient photocurrent measurements, as well as measurements of the open-circuit photovoltage decay (OCVD) were performed to confirm this conclusion and, further, to prove a reduced rate of recombination for these injected electrons which prevented a corresponding decrease in the open-circuit voltage for many cells, frequently observed earlier. It is therefore shown how the long-term stability of ZnO-based DSSCs can be improved.

Photoisomerization pathways and Raman activity of 1,1'-difluorostilbene.

The photoisomerization of 1,1'-difluorostilbene, following S0→S1 optical excitation in solution, was studied with femtosecond broadband transient absorption and stimulated Raman spectroscopy, and by quantum-chemical calculations. In n-hexane, trans-to-cis (t→c) isomerization starts with Franck-Condon relaxation (τ1t = 0.07 ps) followed by nearly barrierless torsion around the ethylenic bond (τ2t ≈ 0.3 ps) to a perpendicular conformation P. About 50% of the excited molecules are trapped in P, while others reach the S1(cis) conformation adiabatically. For the opposite cis-to-trans (c→t) path, the dynamics in n-hexane (τ1c = 0.04 ps, τ2c = 0.7 ps) suggest a 5 kJ/mol barrier between the relaxed S1(cis) and P states. The subsequent P decay with τ3 = 0.4 ps is followed by much slower ground-state recovery (τ4 ≈ 3 ps), indicating an intermediate state X. The t→P and c→P torsion depend on solvent viscosity and polarity, whereas the P→X→S0 relaxation and residual torsion is viscosity-independent but still polarity-dependent. Photoisomerization yields are derived from the transient absorption data and compared to those from actinometric measurements. Low-frequency oscillations in the transient signal are assigned to nuclei motions. Transient and stationary stimulated Raman spectra are compared to calculations. Early Franck-Condon Raman spectra differ from those of the quasistationary trans or cis S1 state. The photoisomerization behavior of stilbene and vinyl-substituted derivatives is compared and the general features are discussed.

Sensitivity to change of the Dermatology Life Quality Index in adult females with facial acne vulgaris: a validation study.

BACKGROUND: The postadolescent form of acne papulopustulosa, also referred to as 'acne tarda' can have substantial negative impact on Quality of Life, especially in adult female patients. OBJECTIVE: Although the Dermatology Life Quality Index (DLQI) is widely used, empirical evidence about its performance in adult female acne patients is lacking. METHODS: In this prospective cohort study, we have investigated the sensitivity to change of the DLQI in 53 female adult acne patients with mild to moderate facial acne treated with azelaic acid (AzA) 15% gel twice daily over 24 weeks. RESULTS: Mean Investigator Static Global Assessment (ISGA) score was 2.3 (SD 0.5) at baseline and ranged from 0.9 (SD 0.3) to 2.1 (SD 0.4) at the end of the study in the 'Highly Improved' and 'Unchanged' responder groups respectively. The mean baseline DLQI score was 5.1 (SD 4.2). The Effect Size in the responder group 'Highly Improved' was 0.66; in group 'Improved' 0.62 and 0.23 in group 'Unchanged'. At the end of study, the mean DLQI score ranged from 1.1 (SD 1.5) in the 'Highly Improved' group to 3.7 (SD 6.0) in the 'Unchanged' group. CONCLUSION: The results support the sensitivity to change of the DLQI in this population.

Athletic groin pain (part 2): a prospective cohort study on the biomechanical evaluation of change of direction identifies three clusters of movement patterns.

BACKGROUND: Athletic groin pain (AGP) is prevalent in sports involving repeated accelerations, decelerations, kicking and change-of-direction movements. Clinical and radiological examinations lack the ability to assess pathomechanics of AGP, but three-dimensional biomechanical movement analysis may be an important innovation. AIM: The primary aim was to describe and analyse movements used by patients with AGP during a maximum effort change-of-direction task. The secondary aim was to determine if specific anatomical diagnoses were related to a distinct movement strategy. METHODS: 322 athletes with a current symptom of chronic AGP participated. Structured and standardised clinical assessments and radiological examinations were performed on all participants. Additionally, each participant performed multiple repetitions of a planned maximum effort change-of-direction task during which whole body kinematics were recorded. Kinematic and kinetic data were examined using continuous waveform analysis techniques in combination with a subgroup design that used gap statistic and hierarchical clustering. RESULTS: Three subgroups (clusters) were identified. Kinematic and kinetic measures of the clusters differed strongly in patterns observed in thorax, pelvis, hip, knee and ankle. Cluster 1 (40%) was characterised by increased ankle eversion, external rotation and knee internal rotation and greater knee work. Cluster 2 (15%) was characterised by increased hip flexion, pelvis contralateral drop, thorax tilt and increased hip work. Cluster 3 (45%) was characterised by high ankle dorsiflexion, thorax contralateral drop, ankle work and prolonged ground contact time. No correlation was observed between movement clusters and clinically palpated location of the participant's pain. CONCLUSIONS: We identified three distinct movement strategies among athletes with long-standing groin pain during a maximum effort change-of-direction task These movement strategies were not related to clinical assessment findings but highlighted targets for rehabilitation in response to possible propagative mechanisms. TRIAL REGISTRATION NUMBER: NCT02437942, pre results.

Virological and Social Outcomes of HIV-Infected Adolescents and Young Adults in The Netherlands Before and After Transition to Adult Care.

BACKGROUND: As a result of effective combination antiretroviral therapy (cART) and advanced supportive healthcare, a growing number of human immunodeficiency virus (HIV)-infected children survive into adulthood. The period of transition to adult care is often associated with impaired adherence to treatment and discontinuity of care. We aimed to evaluate virological and social outcomes of HIV-infected adolescents and young adults (AYAs) before and after transition, and explore which factors are associated with virological failure. METHODS: We included 59 HIV-infected AYAs from the Netherlands who had entered into pediatric care and transitioned from pediatric to adult healthcare. We used HIV RNA load and cART data from the Dutch Stichting HIV Monitoring database (1996-2014), and collected social and treatment data from patients' medical records from all Dutch pediatric HIV treatment centers and 14 Dutch adult treatment centers involved. We evaluated risk factors for virological failure (VF) in a logistic regression model adjusted for repeated measurements. RESULTS: HIV VF occurred frequently during the study period (14%-36%). During the transition period (from 18 to 19 years of age) there was a significant increase in VF compared with the reference group of children aged 12-13 years (odds ratio, 4.26 [95% confidence interval, 1.12-16.28]; P = .03). Characteristics significantly associated with VF were low educational attainment and lack of autonomy regarding medication adherence at transition. CONCLUSIONS: HIV-infected AYAs are vulnerable to VF, especially during the transition period. Identification of HIV-infected adolescents at high risk for VF might help to improve treatment success in this group.

(19)F-labeling of the adenine H2-site to study large RNAs by NMR spectroscopy.

In comparison to proteins and protein complexes, the size of RNA amenable to NMR studies is limited despite the development of new isotopic labeling strategies including deuteration and ligation of differentially labeled RNAs. Due to the restricted chemical shift dispersion in only four different nucleotides spectral resolution remains limited in larger RNAs. Labeling RNAs with the NMR-active nucleus (19)F has previously been introduced for small RNAs up to 40 nucleotides (nt). In the presented work, we study the natural occurring RNA aptamer domain of the guanine-sensing riboswitch comprising 73 nucleotides from Bacillus subtilis. The work includes protocols for improved in vitro transcription of 2-fluoroadenosine-5'-triphosphat (2F-ATP) using the mutant P266L of the T7 RNA polymerase. Our NMR analysis shows that the secondary and tertiary structure of the riboswitch is fully maintained and that the specific binding of the cognate ligand hypoxanthine is not impaired by the introduction of the (19)F isotope. The thermal stability of the (19)F-labeled riboswitch is not altered compared to the unmodified sequence, but local base pair stabilities, as measured by hydrogen exchange experiments, are modulated. The characteristic change in the chemical shift of the imino resonances detected in a (1)H,(15)N-HSQC allow the identification of Watson-Crick base paired uridine signals and the (19)F resonances can be used as reporters for tertiary and secondary structure transitions, confirming the potential of (19)F-labeling even for sizeable RNAs in the range of 70 nucleotides.

Follicular fluorescence quantity to characterize acne severity: a validation study.

BACKGROUND: Porphyrins are native fluorophores in the follicle openings, visible under ultraviolet-A light. Acne severity might be associated with increased Propionibacterium acnes colonization and porphyrin production. Aim of this study was to investigate whether the parameter fluorescence quantity can be used to measure acne severity. METHODS: A validation study was conducted in 24 patients with acne using split-face design. Acne severity was measured using Investigator Static Global Assessment scores and lesion counts. Reliability, construct validity and sensitivity to change in fluorescence quantity were investigated. RESULTS: Mean baseline Investigator Static Global Assessment score was 2.7 (SD 0.1). Mean baseline fluorescence quantities were 24.8 (SD 4.0) on the cheek and 20.3 (SD 4.6) on the chin. On day 25, values ranged from 6.0 (SD 6.0) to 18.1 (SD 18.4) on the cheek and from 2.6 (SD 4.4) to 14.7 (SD 16.2) on the chin. The intraclass correlation coefficients of fluorescence quantity ranged from 0.513 to 0.987. Effect sizes for fluorescence measurements were highest on the chin and cheek ranging from 0.24 to 0.77 and 0.32 to 0.75, respectively. CONCLUSION: Fluorescence quantity indicates acne severity, especially on the inner cheek and chin areas. Fluorescence quantity is reliable but is not as sensitive as manual lesion counting.

Dissemination strategies and adherence predictors for web-based interventions-how efficient are patient education sessions and email reminders?

The Internet offers the potential to efficaciously deliver health interventions at a low cost and with a low threshold across any distance. However, since many web-based interventions are confronted with low use and adherence, proactive dissemination strategies are needed. We, therefore, tested the efficacy of a 1-h patient education session as part of a rehabilitation program and an email reminder 4 weeks later on the publicity and use of a web-based intervention aimed at lifestyle changes in patients with either coronary heart disease or chronic back pain (CBP) and examined adherence predictors. The website www.lebensstil-aendern.de is a cost-free, German-language website providing more than 1000 patient narratives about successful lifestyle changes. To test the efficacy of the dissemination strategies and to examine adherence predictors, we conducted a sequential controlled trial with heart and CBP patients recruited from German inpatient rehabilitation centers. The dissemination strategies were found to be efficient. Use rates, however, remained low. The email reminder and internal health locus of control emerged as notable factors in motivating patients to participate in the web-based intervention. Other factors that have been suggested to be related to nonuse, e.g. sociodemographic characteristics and medical condition, did not predict use or adherence.

Large-amplitude internal waves benefit corals during thermal stress.

Tropical scleractinian corals are particularly vulnerable to global warming as elevated sea surface temperatures (SSTs) disrupt the delicate balance between the coral host and their algal endosymbionts, leading to symbiont expulsion, mass bleaching and mortality. While satellite sensing of SST has proved a reliable predictor of coral bleaching at the regional scale, there are large deviations in bleaching severity and mortality on the local scale that are poorly understood. Here, we show that internal waves play a major role in explaining local coral bleaching and mortality patterns in the Andaman Sea. Despite a severe region-wide SST anomaly in May 2010, frequent upslope intrusions of cold sub-pycnocline waters due to breaking large-amplitude internal waves (LAIW) mitigated coral bleaching and mortality in shallow waters. In LAIW-sheltered waters, by contrast, bleaching-susceptible species suffered severe bleaching and total mortality. These findings suggest that LAIW benefit coral reefs during thermal stress and provide local refugia for bleaching-susceptible corals. LAIW are ubiquitous in tropical stratified waters and their swash zones may thus be important conservation areas for the maintenance of coral diversity in a warming climate. Taking LAIW into account can significantly improve coral bleaching predictions and provide a valuable tool for coral reef conservation and management.

Efficacy of tenofovir and efavirenz in combination with lamivudine or emtricitabine in antiretroviral-naive patients in Europe.

BACKGROUND: The combination of tenofovir and efavirenz with either lamivudine or emtricitabine (TELE) has proved to be highly effective in clinical trials for first-line treatment of HIV-1 infection. However, limited data are available on its efficacy in routine clinical practice. METHODS: A multicentre cohort study was performed in therapy-naive patients initiating ART with TELE before July 2009. Efficacy was studied using ITT (missing or switch = failure) and on-treatment (OT) analyses. Genotypic susceptibility scores (GSSs) were determined using the Stanford HIVdb algorithm. RESULTS: Efficacy analysis of 1608 patients showed virological suppression to <50 copies/mL at 48 weeks in 91.5% (OT) and 70.6% (ITT). Almost a quarter of all patients (22.9%) had discontinued TELE at week 48, mainly due to CNS toxicity. Virological failure within 48 weeks was rarely observed (3.3%, n = 53). In multilevel, multivariate analysis, infection with subtype B (P = 0.011), baseline CD4 count <200 cells/mm³ (P < 0.001), GSS <3 (P = 0.002) and use of lamivudine (P < 0.001) were associated with a higher risk of virological failure. After exclusion of patients using co-formulated compounds, virological failure was still more often observed with lamivudine. Following virological failure, three-quarters of patients switched to a PI-based regimen with GSS <3. After 1 year of second-line therapy, viral load was suppressed to <50 copies/mL in 73.5% (OT). CONCLUSIONS: In clinical practice, treatment failure on TELE regimens is relatively frequent due to toxicity. Virological failure is rare and more often observed with lamivudine than with emtricitabine. Following virological failure on TELE, PI-based second-line therapy was often successful despite GSS <3.

Risk of non-AIDS-defining events among HIV-infected patients not yet on antiretroviral therapy.

OBJECTIVES: Certain non-AIDS-related diseases have been associated with immunodeficiency and HIV RNA levels in HIV-infected patients on combination antiretroviral therapy (cART). We aimed to investigate these associations in patients not yet on cART, when potential antiretroviral-drug-related effects are absent and variation in RNA levels is greater. METHODS: Associations between, on the one hand, time-updated CD4 counts and plasma HIV RNA and, on the other hand, a composite non-AIDS-related endpoint, including major cardiovascular diseases, liver fibrosis/cirrhosis, and non-AIDS-related malignancies, were studied with multivariate Poisson regression models in 12 800 patients diagnosed with HIV infection from 1998 onwards while not yet treated with cART. RESULTS: During 18 646 person-years of follow-up, 203 non-AIDS-related events occurred. Compared with a CD4 count ≥ 500 cells/µL, adjusted relative risks (RRs) for the composite endpoint were 4.71 [95% confidence interval (CI) 2.98-7.45] for a CD4 count < 200 cells/µL, 2.06 (95% CI 1.38-3.06) for a CD4 count of 200-349 cells/µL, and 1.19 (95% CI 0.82-1.74) for a CD4 count of 350-499 cells/µL. There was no evidence for an independent association with HIV RNA. Other important covariates were age [RR 1.40 (95% CI 1.31-1.49) per 5 years older], hepatitis B virus coinfection [RR 5.66 (95% CI 3.87-8.28)] and hepatitis C virus coinfection [RR 9.26 (95% CI 6.04-14.2)]. CONCLUSIONS: In persons not yet receiving cART, a more severe degree of immunodeficiency rather than higher HIV RNA levels appears to be associated with an increased risk of our composite non-AIDS-related endpoint. Larger studies are needed to address these associations for individual non-AIDS-related events.