The relationship between wearable-derived sleep features and relapse in Major Depressive Disorder.

BACKGROUND: Changes in sleep and circadian function are leading candidate markers for the detection of relapse in Major Depressive Disorder (MDD). Consumer-grade wearable devices may enable remote and real-time examination of dynamic changes in sleep. Fitbit data from individuals with recurrent MDD were used to describe the longitudinal effects of sleep duration, quality, and regularity on subsequent depression relapse and severity. METHODS: Data were collected as part of a longitudinal observational mobile Health (mHealth) cohort study in people with recurrent MDD. Participants wore a Fitbit device and completed regular outcome assessments via email for a median follow-up of 541 days. We used multivariable regression models to test the effects of sleep features on depression outcomes. We considered respondents with at least one assessment of relapse (n = 218) or at least one assessment of depression severity (n = 393). RESULTS: Increased intra-individual variability in total sleep time, greater sleep fragmentation, lower sleep efficiency, and more variable sleep midpoints were associated with worse depression outcomes. Adjusted Population Attributable Fractions suggested that an intervention to increase sleep consistency in adults with MDD could reduce the population risk for depression relapse by up to 22 %. LIMITATIONS: Limitations include a potentially underpowered primary outcome due to the smaller number of relapses identified than expected. CONCLUSION: Our study demonstrates a role for consumer-grade activity trackers in estimating relapse risk and depression severity in people with recurrent MDD. Variability in sleep duration and midpoint may be useful targets for stratified interventions.

Predictors of engagement with remote sensing technologies for symptom measurement in Major Depressive Disorder.

BACKGROUND: Remote sensing for the measurement and management of long-term conditions such as Major Depressive Disorder (MDD) is becoming more prevalent. User-engagement is essential to yield any benefits. We tested three hypotheses examining associations between clinical characteristics, perceptions of remote sensing, and objective user engagement metrics. METHODS: The Remote Assessment of Disease and Relapse - Major Depressive Disorder (RADAR-MDD) study is a multicentre longitudinal observational cohort study in people with recurrent MDD. Participants wore a FitBit and completed app-based assessments every two weeks for a median of 18 months. Multivariable random effects regression models pooling data across timepoints were used to examine associations between variables. RESULTS: A total of 547 participants (87.8% of the total sample) were included in the current analysis. Higher levels of anxiety were associated with lower levels of perceived technology ease of use; increased functional disability was associated with small differences in perceptions of technology usefulness and usability. Participants who reported higher system ease of use, usefulness, and acceptability subsequently completed more app-based questionnaires and tended to wear their FitBit activity tracker for longer. All effect sizes were small and unlikely to be of practical significance. LIMITATIONS: Symptoms of depression, anxiety, functional disability, and perceptions of system usability are measured at the same time. These therefore represent cross-sectional associations rather than predictions of future perceptions. CONCLUSIONS: These findings suggest that perceived usability and actual use of remote measurement technologies in people with MDD are robust across differences in severity of depression, anxiety, and functional impairment.

Spinal trauma with a complete anterior vertebral body dislocation: a report of three cases.

STUDY DESIGN: Retrospective review of three cases. OBJECTIVES: Severe trauma can be responsible for a complete spinal anterior dislocation with a 100% anterior slip of the vertebral body. Three cases of this uncommon lesion are reported. SETTING: France. METHODS: The data of three cases of complete spinal anterior dislocation with a 100% anterior slip of the vertebral body were retrospectively reviewed. RESULTS: In all the cases, the vertebral dislocation was responsible for a severe neurological deficit and all patients had severe associated lesions. The diagnosis was made on plain radiographs. In one case of a multilevel injury, an extensive instrumented spinal fusion was necessary. In spite of the severe injury, two neurological deficits improved thanks to pedicular fractures, which widen the canal. CONCLUSION: The therapeutic goal is to achieve emergent vertebral alignment, neurological decompression and solid spinal fusion. A posterior facilitates this. Reduction of vertebral dislocation can be difficult to achieve and it is therefore mandatory to perform complete arthrectomy of the injured levels before reduction. Especially in young patients, severe disc lesions secondary to the wide vertebral displacement make it necessary to perform circumferential fusion.

[Sacroiliac fixation: a new technique after pelvic trauma]. / Une nouvelle technique de fixation sacro-iliaque dans les ruptures traumatiques de l'anneau pelvien.

We propose a new technique for sacroiliac fixation for the treatment of pelvic fracture with vertical and horizontal instability (Tile class C). This fixation technique allows control of vertical displacement while allowing, if needed, a certain degree of movement in the horizontal plane to facilitate reduction of anterior lesions. The technique involves insertion of two sacral screws, one in S1 and one in S2, and two iliac screws. The iliac screws are inserted in the posterior iliac crest through two sacroiliac connectors placed on a rod linking the two sacral screws. Vertical displacement is controlled by blocking the screw heads on the connecting rod. If needed, a certain degree of horizontal mobility of the half pelvis can be allowed by loosening the connectors on the rods. This technique was used for 4 patients. Anatomic reduction was achieved and no secondary movement of the osteosynthesis material nor secondary displacement were observed. The quality of the fixation allowed rapid weight bearing in the standing position and early walking without crutches. This type of fixation can only be used for type C12 fractures in the Tile classification.

[Treatment of an exposed femorol-popliteal bypass: ex-situ replacement]. / Traitement d'un pontage fémoro-poplité exposé: remplacement ex-situ.

From December 1990 to July 1995 we performed 171 sub-inguinal revascularizations including 35 popliteal revascularizations and 146 revascularizations of an artery in the leg or foot. Five cases of infection were observed within a delay of 7 and 25 days after the operation. There were 3 men and 2 women (mean age 78 years). Four femoro-tibial bypasses were made for critical ischaemia (2 necroses of the toes, one eschar of the heal, one stage III). There was one femoro-popliteal bypass which was associated with a femoro-femoral for necrosis of the toes. Two bypasses were made with polytetrafluoroethylene, one with Dacron and two with the greater saphenous vein. Signs of sepsis were bleeding in 2 patients who had a venous bypass and septicaemia in 2 patients. Local skin necrosis and/or apparently infected discharge or patent pus were seen in all patients. Staphylococcus aureus was found in 4 patients and Enterobacter cloacae in one. Revascularization was done with an extra-anatomic bypass in 4 patients and with a cryopreserved in situ allograft in 1. Mortality was 20% and amputation rate was 40%. All exposed bypasses were infected but the severity of the infection varied depending on the causal germ, general signs and ischaemia of the limb. Conservative treatment has its limits: 1) intact anastomoses, 2) absence of bleeding, 3) patent bypass, 4) absence of generalized sepsis. Results of in situ revascularization depend on the virulence of the causal germ. Radical treatment (explanation + extra-anatomic revascularization) still has indications in infected infra-inguinal bypass surgery.

Evaluation of an antimicrobial soap formula for virucidal efficacy in vitro against human immunodeficiency virus in a blood-virus mixture.

The virucidal efficacy of a health care personnel hand wash product containing 0.5% parachlorometaxylenol in a sodium C14-16 olefin sulfonate formula was evaluated in in vitro tests with human immunodeficiency virus type 1 (HIV-1) in the presence of 50% whole human blood. The HTLV-IIIRF strain of HIV-1 was suspended in 50% medium-50% whole human blood and exposed to various dilutions of the hand wash product for 30 or 60 s. Following detoxification, residual infectivity was determined by a lytic cytopathogenic assay in MT2 cell cultures. No infectious HIV could be detected after a 30-s exposure to the hand wash product at dilutions of 1:5 and 1:10 and after a 60-s exposure at dilutions of 1:5, 1:10, 1:20, and 1:30. More than 99.9% of the virus was inactivated at these dilutions and exposure times.

Potent and selective activity of a new carbocyclic nucleoside analog (carbovir: NSC 614846) against human immunodeficiency virus in vitro.

Carbocyclic 2',3'-didehydro-2',3'-dideoxyguanosine (Carbovir: NSC 614846), a novel nucleoside analog, emerged as a potent and selective anti-HIV agent from a large screening program conducted by the National Cancer Institute and its contractors. Its hydrolytic stability and its ability to inhibit the infectivity and replication of HIV in T-cells at concentrations of approximately 200- to 400-fold below toxic concentrations make carbovir a top-priority candidate for development as a potential antiretroviral agent in the treatment of AIDS patients.

Expression of baboon endogenous virus in exogenously infected baboon cells.

Strains of low-passage, fetal diploid, baboon (Papio cynocephalus) fibroblasts were susceptible to exogenous infection with three independent isolates of baboon endogenous virus, as measured by an immunofluorescence assay specific for viral p28. Infectivity of the M7 strain of baboon endogenous virus for baboon cells of fetal skin muscle origin was equivalent to that for human and dog cells in that similar, linear, single-hit titration patterns were obtained. The assay for supernatant RNA-dependent DNA polymerase, however, showed that baboon cells produced only low levels of virus after infection compared with the production by heterologous cells. The results showed that baboon endogenous virus was capable of penetrating baboon cells and that viral genes were expressed in infected cells. Replication of complete infectious virus was restricted, however, indicating that in this primate system homologous cells differentially regulated the expression of viral genes.

Immunofluorescent analysis of murine leukemia virus-infected cells by flow microfluorometry.

Flow microfluorometric assay with a Cytofluorograf model 4801 in combination with immunofluorescence was applied to the quantitative assay of cells exogenously infected with mouse leukemia viruses and to the chemical induction of virus in AKR cells. The Cytofluorograf provides sensitivity equal to the visual method and is capable of assaying up to 5000 cells/sec with specificity equivalent to that of the direct visual immunofluorescence assay, thereby providing a large, statistically valid sampling in a fraction of the time required by visual counting. Flow microfluorometry also provides a method of quantitatively resolving fluorescent cell populations on the basis of relative size and degree of fluorescence.

Isolation and partial characterization of single-stranded adenoviral DNA produced during synthesis of adenovirus type 2 DNA.

Single-stranded fragments of adenovirus type 2 DNA were isolated from infected KB cells under conditions which retarded reassociation of complementary sequences but did not denature native viral DNA. Of the total intracellular, virus-specific DNA labeled during a 1-h pulse with tritiated thymidine begining 15 h after infection, about 20% was single stranded when fractionated on hydroxylapatite. This DNA shifted predominantly to the double-stranded fraction on hydroxylapatite during an extended chase incubation, suggesting that it may represent single-stranded DNA in replicating intermediates. Furthermore, the single-stranded DNA annealed nearly equally to both strands of the adenovirus genome. These findings indicate that at least portions of both complementary strands of adenovirus type 2 DNA are exposed as single strands during the period of viral DNA synthesis.

Multiplicity of Scrapie virus in infected mouse spleen cells in vivo.

Subpopulations of spleen cells from scrapie virus-infected mice were used to determine the average virus content of infected cells in vivo at a time when virus was rapidly increasing in titer in lymphoreticular tissues. Comparison of the mean lethal doses of lysed to intact cells indicated averages of 2 to 6 infectious units per infected cell. In another experiment, preparations of cytoplasmic nucleic acids extracted from spleen cells of infected mice had no detectable infectivity, which suggests that the transmissible form of the virus is not a free nucleic acid.

Isolation from mouse spleen of cell populations with high specific infectivity for scrapie virus.

Spleen cells from mice infected with scrapie virus were separated into subpopulations on the basis of buoyant density in discontinuous gradients of isotonic albumin or differential adherence of cells to plastic. At three different intervals after infection, a population of "less dense" cells was found in albumin gradients that had 40-to 60-fold higher specific infectivity (cells per median lethal dose) than the total cell suspension before gradient sedimentation. The class of cells associated with high relative specific infectivity has a density characteristic of lymphoblasts, myeloblasts, and macrophages. Separation of "macrophage rich" cells on the basis of adherence to plastic did not result in significant enrichment of scrapie virus-infected cells.

Antigenic and morphological similarities of progressive pneumonia virus, a recently isolated "slow virus" of sheep, to visna and maedi viruses.

Progressive pneumonia virus, the causative agent of a slow, pulmonary disease of Montana sheep, was shown to be antigenically related to two other slow viruses of sheep, visna and maedi. Electron microscopic examination of infected cells revealed that the virus matures by a budding process and that the budding particles as well as the mature, extracellular virions bear striking resemblances to the oncogenic ribonucleic acid (RNA) viruses. Recent findings of an RNA-dependent deoxyribonucleic acid polymerase associated with the virions of this group of slow viruses lend further support to the notion that they may tentatively be classified with the oncogenic RNA tumor viruses.