417 research outputs found

    Radiostereometric Evaluation of Tendon Elongation After Distal Biceps Repair.

    Get PDF
    BACKGROUND: Operative repair of distal biceps tendon ruptures has shown successful outcomes. However, little is known about the amount of tendon or repair site lengthening after repair. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate distal biceps tendon repair via intratendinous radiostereometric analysis to analyze tendon lengthening at different time intervals of healing. The hypothesis was that there is significant lengthening after repair. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Eleven patients with distal biceps ruptures requiring operative repair were recruited. During repair, two 2-mm tantalum beads with laser-etched holes were sutured to the distal biceps tendon. Beads were evaluated via computed tomography scans immediately postoperatively and at 16 weeks. Radiographs were obtained at time 0 and then at 4, 8, and 16 weeks postoperatively. Measurements were made using the button-to-bead and bead-to-bead distances to assess repair site elongation as well as tendon elongation over time. After final follow-up, patients filled out the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and underwent ultrasound to confirm the integrity of the tendon. RESULTS: Ten patients had complete ruptures, with 1 having a partial rupture that underwent completion of the tear and subsequent repair. All patients showed statistically significant lengthening after surgery. The mean amount of tendon lengthening after surgery was 22.8 mm (range, 11.2-30.9 mm; P \u3c .05), and the repair site lengthened a mean 17.0 mm (range, 9.6-30.6 mm; P \u3c .05) from surgery to final follow-up. The greatest change in lengthening was noted between time 0 and week 4 (mean, 11.3 mm; P \u3c .05), with the least amount of lengthening between weeks 8 and 16 (mean, 2.6 mm; P \u3c .05). The mean DASH score was 11.2. Final ultrasound evaluations found all tendons to be in continuity. CONCLUSION: All patients undergoing distal biceps tendon repair have significant elongation after surgery, with the greatest amount of lengthening seen in the early postoperative period

    A multi-centre qualitative study exploring the experiences of UK South Asian and White Diabetic Patients referred for renal care

    Get PDF
    Background An exploration of renal complications of diabetes from the patient perspective is important for developing quality care through the diabetic renal disease care pathway. Methods Newly referred South Asian and White diabetic renal patients over 16 years were recruited from nephrology outpatient clinics in three UK centres - Luton, West London and Leicester – and their experiences of the diabetes and renal care recorded. A semi-structured qualitative interview was conducted with 48 patients. Interview transcripts were analysed thematically and comparisons made between the White and South Asian groups. Results 23 South Asian patients and 25 White patients were interviewed. Patient experience of diabetes ranged from a few months to 35 years with a mean time since diagnosis of 12.1 years and 17.1 years for the South Asian and White patients respectively. Confusion emerged as a response to referral shared by both groups. This sense of confusion was associated with reported lack of information at the time of referral, but also before referral. Language barriers exacerbated confusion for South Asian patients. Conclusions The diabetic renal patients who have been referred for specialist renal care and found the referral process confusing have poor of awareness of kidney complications of diabetes. Healthcare providers should be more aware of the ongoing information needs of long term diabetics as well as the context of any information exchange including language barriers

    Multipole interaction between atoms and their photonic environment

    Get PDF
    Macroscopic field quantization is presented for a nondispersive photonic dielectric environment, both in the absence and presence of guest atoms. Starting with a minimal-coupling Lagrangian, a careful look at functional derivatives shows how to obtain Maxwell's equations before and after choosing a suitable gauge. A Hamiltonian is derived with a multipolar interaction between the guest atoms and the electromagnetic field. Canonical variables and fields are determined and in particular the field canonically conjugate to the vector potential is identified by functional differentiation as minus the full displacement field. An important result is that inside the dielectric a dipole couples to a field that is neither the (transverse) electric nor the macroscopic displacement field. The dielectric function is different from the bulk dielectric function at the position of the dipole, so that local-field effects must be taken into account.Comment: 17 pages, to be published in Physical Review

    Self-Assembled Nanoparticle Drumhead Resonators

    Get PDF
    The self-assembly of nanoscale structures from functional nanoparticles has provided a powerful path to developing devices with emergent properties from the bottomup. Here we demonstrate that freestanding sheets selfassembled from various nanoparticles form versatile nanomechanical resonators in the megahertz frequency range. Using spatially resolved laser-interferometry to measure thermal vibrational spectra and image vibration modes, we show that their dynamic behavior is in excellent agreement with linear elastic response for prestressed drumheads of negligible bending stiffness. Fabricated in a simple one-step drying-mediated process, these resonators are highly robust and their inorganic−organic hybrid nature offers an extremely low mass, low stiffness, and the potential to couple the intrinsic functionality of the nanoparticle building blocks to nanomechanical motion

    All-cause hospitalisation among people living with HIV according to gender, mode of HIV acquisition, ethnicity, and geographical origin in Europe and North America: findings from the ART-CC cohort collaboration

    Get PDF
    BACKGROUND: Understanding demographic disparities in hospitalisation is crucial for the identification of vulnerable populations, interventions, and resource planning. METHODS: Data were from the Antiretroviral Therapy Cohort Collaboration (ART-CC) on people living with HIV in Europe and North America, followed up between January, 2007 and December, 2020. We investigated differences in all-cause hospitalisation according to gender and mode of HIV acquisition, ethnicity, and combined geographical origin and ethnicity, in people living with HIV on modern combination antiretroviral therapy (cART). Analyses were performed separately for European and North American cohorts. Hospitalisation rates were assessed using negative binomial multilevel regression, adjusted for age, time since cART intitiaion, and calendar year. FINDINGS: Among 23 594 people living with HIV in Europe and 9612 in North America, hospitalisation rates per 100 person-years were 16·2 (95% CI 16·0-16·4) and 13·1 (12·8-13·5). Compared with gay, bisexual, and other men who have sex with men, rates were higher for heterosexual men and women, and much higher for men and women who acquired HIV through injection drug use (adjusted incidence rate ratios ranged from 1·2 to 2·5 in Europe and from 1·2 to 3·3 in North America). In both regions, individuals with geographical origin other than the region of study generally had lower hospitalisation rates compared with those with geographical origin of the study country. In North America, Indigenous people and Black or African American individuals had higher rates than White individuals (adjusted incidence rate ratios 1·9 and 1·2), whereas Asian and Hispanic people living with HIV had somewhat lower rates. In Europe there was a lower rate in Asian individuals compared with White individuals. INTERPRETATION: Substantial disparities exist in all-cause hospitalisation between demographic groups of people living with HIV in the current cART era in high-income settings, highlighting the need for targeted support. FUNDING: Royal Free Charity and the National Institute on Alcohol Abuse and Alcoholism

    Impact of risk factors for specific causes of death in the first and subsequent years of antiretroviral therapy among HIV-infected patients.

    Get PDF
    BACKGROUND: Patterns of cause-specific mortality in individuals infected with human immunodeficiency virus type 1 (HIV-1) are changing dramatically in the era of antiretroviral therapy (ART). METHODS: Sixteen cohorts from Europe and North America contributed data on adult patients followed from the start of ART. Procedures for coding causes of death were standardized. Estimated hazard ratios (HRs) were adjusted for transmission risk group, sex, age, year of ART initiation, baseline CD4 count, viral load, and AIDS status, before and after the first year of ART. RESULTS: A total of 4237 of 65 121 (6.5%) patients died (median, 4.5 years follow-up). Rates of AIDS death decreased substantially with time since starting ART, but mortality from non-AIDS malignancy increased (rate ratio, 1.04 per year; 95% confidence interval [CI], 1.0-1.1). Higher mortality in men than women during the first year of ART was mostly due to non-AIDS malignancy and liver-related deaths. Associations with age were strongest for cardiovascular disease, heart/vascular, and malignancy deaths. Patients with presumed transmission through injection drug use had higher rates of all causes of death, particularly for liver-related causes (HRs compared with men who have sex with men: 18.1 [95% CI, 6.2-52.7] during the first year of ART and 9.1 [95% CI, 5.8-14.2] thereafter). There was a persistent role of CD4 count at baseline and at 12 months in predicting AIDS, non-AIDS infection, and non-AIDS malignancy deaths. Lack of viral suppression on ART was associated with AIDS, non-AIDS infection, and other causes of death. CONCLUSIONS: Better understanding of patterns of and risk factors for cause-specific mortality in the ART era can aid in development of appropriate care for HIV-infected individuals and inform guidelines for risk factor management

    Impact of Risk Factors for Specific Causes of Death in the First and Subsequent Years of Antiretroviral Therapy Among HIV-Infected Patients

    Get PDF
    Among HIV-infected patients who initiated antiretroviral therapy (ART), patterns of cause-specific death varied by ART duration and were strongly related to age, sex, and transmission risk group. Deaths from non-AIDS malignancies were much more frequent than those from cardiovascular diseas

    Cohort Profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

    Get PDF
    The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70 000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org

    Heterogeneity in outcomes of treated HIV-positive patients in Europe and North America: relation with patient and cohort characteristics

    Get PDF
    Background HIV cohort collaborations, which pool data from diverse patient cohorts, have provided key insights into outcomes of antiretroviral therapy (ART). However, the extent of, and reasons for, between-cohort heterogeneity in rates of AIDS and mortality are unclear. Methods We obtained data on adult HIV-positive patients who started ART from 1998 without a previous AIDS diagnosis from 17 cohorts in North America and Europe. Patients were followed up from 1 month to 2 years after starting ART. We examined between-cohort heterogeneity in crude and adjusted (age, sex, HIV transmission risk, year, CD4 count and HIV-1 RNA at start of ART) rates of AIDS and mortality using random-effects meta-analysis and meta-regression. Results During 61 520 person-years, 754/38 706 (1.9%) patients died and 1890 (4.9%) progressed to AIDS. Between-cohort variance in mortality rates was reduced from 0.84 to 0.24 (0.73 to 0.28 for AIDS rates) after adjustment for patient characteristics. Adjusted mortality rates were inversely associated with cohorts' estimated completeness of death ascertainment [excellent: 96-100%, good: 90-95%, average: 75-89%; mortality rate ratio 0.66 (95% confidence interval 0.46-0.94) per category]. Mortality rate ratios comparing Europe with North America were 0.42 (0.31-0.57) before and 0.47 (0.30-0.73) after adjusting for completeness of ascertainment. Conclusions Heterogeneity between settings in outcomes of HIV treatment has implications for collaborative analyses, policy and clinical care. Estimated mortality rates may require adjustment for completeness of ascertainment. Higher mortality rate in North American, compared with European, cohorts was not fully explained by completeness of ascertainment and may be because of the inclusion of more socially marginalized patients with higher mortality ris

    Life expectancy after 2015 of adults with HIV on long-term antiretroviral therapy in Europe and North America: a collaborative analysis of cohort studies

    Get PDF
    BACKGROUND: The life expectancy of people with HIV taking antiretroviral therapy (ART) has increased substantially over the past 25 years. Most previous studies of life expectancy were based on data from the first few years after starting ART, when mortality is highest. However, many people with HIV have been successfully treated with ART for many years, and up-to-date prognosis data are needed. We aimed to estimate life expectancy in adults with HIV on ART for at least 1 year in Europe and North America from 2015 onwards. METHODS: We used data for people with HIV taking ART from the Antiretroviral Therapy Cohort Collaboration and the UK Collaborative HIV Cohort Study. Included participants started ART between 1996 and 2014 and had been on ART for at least 1 year by 2015, or started ART between 2015 and 2019 and survived for at least 1 year; all participants were aged at least 16 years at ART initiation. We used Poisson models to estimate the associations between mortality and demographic and clinical characteristics, including CD4 cell count at the start of follow-up. We also estimated the remaining years of life left for people with HIV aged 40 years who were taking ART, and stratified these estimates by variables associated with mortality. These estimates were compared with estimates for years of life remaining in a corresponding multi-country general population. FINDINGS: Among 206 891 people with HIV included, 5780 deaths were recorded since 2015. We estimated that women with HIV at age 40 years had 35·8 years (95% CI 35·2-36·4) of life left if they started ART before 2015, and 39·0 years (38·5-39·5) left if they started ART after 2015. For men with HIV, the corresponding estimates were 34·5 years (33·8-35·2) and 37·0 (36·5-37·6). Women with CD4 counts of fewer than 49 cells per μL at the start of follow-up had an estimated 19·4 years (18·2-20·5) of life left at age 40 years if they started ART before 2015 and 24·9 years (23·9-25·9) left if they started ART after 2015. The corresponding estimates for men were 18·2 years (17·1-19·4) and 23·7 years (22·7-24·8). Women with CD4 counts of at least 500 cells per μL at the start of follow-up had an estimated 40·2 years (39·7-40·6) of life left at age 40 years if they started ART before 2015 and 42·0 years (41·7-42·3) left if they started ART after 2015. The corresponding estimates for men were 38·0 years (37·5-38·5) and 39·2 years (38·7-39·7). INTERPRETATION: For people with HIV on ART and with high CD4 cell counts who survived to 2015 or started ART after 2015, life expectancy was only a few years lower than that in the general population, irrespective of when ART was started. However, for people with low CD4 counts at the start of follow-up, life-expectancy estimates were substantially lower, emphasising the continuing importance of early diagnosis and sustained treatment of HIV. FUNDING: US National Institute on Alcohol Abuse and Alcoholism and UK Medical Research Council
    corecore