Complications encountered during lengthening over an intramedullary nail

Background: In limb-lengthening, the quest for increased patient comfort and a reduced period of external fixation has led to techniques such as lengthening over an intramedullary nail. The goals of this study were to investigate the rate and types of complications encountered during lengthening over an intramedullary nail and to identify solutions to these complications

Potential barrier increase due to Gd doping of BiFeO3 layers in Nb:SrTiO3-BiFeO3-Pt structures displaying diode-like behavior

The rectifying properties of Nb:SrTiO3-Bi1-xGdxFeO3-Pt structures (x = 0, 0.05, 0.1) displaying diode-like behavior were investigated via current-voltage characteristics at different temperatures. The potential barrier was estimated for negative polarity assuming a Schottky-like thermionic emission with injection controlled by the interface and the drift controlled by the bulk. The height of the potential barrier at the Nb:SrTiO3-Bi1-xGdxFeO3 interface increases with Gd doping. The results are explained by the partial compensation of the p-type conduction due to Bi vacancies with Gd doping in addition to the shift of the Fermi level towards the middle of the bandgap with increasing dopant concentration

Cation ordering in epitaxial lead zirconate titanate films

Electron diffraction and atom location by channeling enhanced microanalysis were used to show that epitaxial PbZr0.2Ti0.8O3 films grown on (001) SrTiO3 substrates by pulsed laser deposition exhibit long-range order on the tetravalent cation sublattice parallel to the film/substrate interface. This ordering gives two distinct tetravalent cation sites, one Zr lean and one Zr rich, and results in a superlattice with a tetragonal unit cell with lattice parameters a(0)approximate to root 2a(PZT) and c(0)approximate to a(PZT). Since such ordered states are inherently unstable in homovalent perovskite solutions, it is inferred that the ordering arises in response to the lattice misfit and could constitute an additional relaxation mode

Census and Analysis of Persistent False-Negative Results in Serological Diagnosis of Human Immunodeficiency Virus Type 1 Group O Infections▿

Human immunodeficiency viruses (HIV) have a high level of genetic diversity. The outlier variants of HIV type 1 (HIV-1) group O are distantly related to HIV-1 group M. Their divergence has an impact on serological diagnosis, with a risk of false-negative results. In this study, we report 20 failure cases, involving patients with primary or chronic infection, in France and Cameroon between 2001 and 2008. Our results indicate that some assays detected group O infection much less efficiently than others. Two major reasons for these false-negative results were identified: the presence or absence of a group O-specific antigen (and the designed sequence) for the detection of antibodies and the greater envelope variability of group O than of group M strains. This study highlights the complexity of screening for these divergent variants and the need to evaluate test performance with a large panel of strains, due to the extensive diversity of group O variants

Outcomes of kidney transplantation in HIV-infected recipients

BACKGROUND: The outcomes of kidney transplantation and immunosuppression in people infected with human immunodeficiency virus (HIV) are incompletely understood. METHODS: We undertook a prospective, nonrandomized trial of kidney transplantation in HIV-infected candidates who had CD4+ T-cell counts of at least 200 per cubic millimeter and undetectable plasma HIV type 1 (HIV-1) RNA levels while being treated with a stable antiretroviral regimen. Post-transplantation management was provided in accordance with study protocols that defined prophylaxis against opportunistic infection, indications for biopsy, and acceptable approaches to immunosuppression, management of rejection, and antiretroviral therapy. RESULTS: Between November 2003 and June 2009, a total of 150 patients underwent kidney transplantation; survivors were followed for a median period of 1.7 years. Patient survival rates (±SD) at 1 year and 3 years were 94.6±2.0% and 88.2±3.8%, respectively, and the corresponding mean graft-survival rates were 90.4% and 73.7%. In general, these rates fall somewhere between those reported in the national database for older kidney-transplant recipients (≥65 years) and those reported for all kidney-transplant recipients. A multivariate proportional-hazards analysis showed that the risk of graft loss was increased among patients treated for rejection (hazard ratio, 2.8; 95% confidence interval [CI], 1.2 to 6.6; P = 0.02) and those receiving antithymocyte globulin induction therapy (hazard ratio, 2.5; 95% CI, 1.1 to 5.6; P = 0.03); living-donor transplants were protective (hazard ratio, 0.2; 95% CI, 0.04 to 0.8; P = 0.02). A higher-than-expected rejection rate was observed, with 1-year and 3-year estimates of 31% (95% CI, 24 to 40) and 41% (95% CI, 32 to 52), respectively. HIV infection remained well controlled, with stable CD4+ T-cell counts and few HIV-associated complications. CONCLUSIONS: In this cohort of carefully selected HIV-infected patients, both patient- and graftsurvival rates were high at 1 and 3 years, with no increases in complications associated with HIV infection. The unexpectedly high rejection rates are of serious concern and indicate the need for better immunotherapy. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT00074386.) Copyright © 2010 Massachusetts Medical Society

Neurologic manifestations of COVID-19 in critically ill patients: results of the prospective multicenter registry PANDEMIC

Background Neurologic manifestations are increasingly reported in patients with coronavirus disease 2019 (COVID-19). Yet, data on prevalence, predictors and relevance for outcome of neurological manifestations in patients requiring intensive care are scarce. We aimed to characterize prevalence, risk factors and impact on outcome of neurologic manifestations in critically ill COVID-19 patients. Methods In the prospective, multicenter, observational registry study PANDEMIC (Pooled Analysis of Neurologic DisordErs Manifesting in Intensive care of COVID-19), we enrolled COVID-19 patients with neurologic manifestations admitted to 19 German intensive care units (ICU) between April 2020 and September 2021. We performed descriptive and explorative statistical analyses. Multivariable models were used to investigate factors associated with disorder categories and their underlying diagnoses as well as to identify predictors of outcome. Results Of the 392 patients included in the analysis, 70.7% (277/392) were male and the mean age was 65.3 (SD +/- 3.1) years. During the study period, a total of 2681 patients with COVID-19 were treated at the ICUs of 15 participating centers. New neurologic disorders were identified in 350 patients, reported by these centers, suggesting a prevalence of COVID-19-associated neurologic disorders of 12.7% among COVID-19 ICU patients. Encephalopathy (46.2%; 181/392), cerebrovascular (41.0%; 161/392) and neuromuscular disorders (20.4%; 80/392) were the most frequent categories identified. Out of 35 cerebrospinal fluid analyses with reverse transcriptase PCR for SARS-COV-2, only 3 were positive. In-hospital mortality was 36.0% (140/389), and functional outcome (mRS 3 to 5) of surviving patients was poor at hospital discharge in 70.9% (161/227). Intracerebral hemorrhage (OR 6.2, 95% CI 2.5-14.9, p < 0.001) and acute ischemic stroke (OR 3.9, 95% CI 1.9-8.2, p < 0.001) were the strongest predictors of poor outcome among the included patients. Conclusions Based on this well-characterized COVID-19 ICU cohort, that comprised 12.7% of all severe ill COVID-19 patients, neurologic manifestations increase mortality and morbidity. Since no reliable evidence of direct viral affection of the nervous system by COVID-19 could be found, these neurologic manifestations may for a great part be indirect para- or postinfectious sequelae of the infection or severe critical illness. Neurologic ICU complications should be actively searched for and treated