bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase II Study of Gonadotropin-Releasing Hormone Analog for Ovarian Function Preservation in Hematopoietic Stem Cell Transplantation Patients
Authors: Cheng Yee Chung , Takagi Mariko , Milbourne Andrea , Champlin Richard E. , Ueno Naoto T.
Published: January 2012

Purpose.

Premature ovarian failure occurs in 40%–70% of patients who receive conventional chemotherapy alone. However, the incidence is higher, 70%–100%, in patients who undergo myeloablative chemotherapy with hematopoietic stem cell transplantation (HSCT). Gonadotropin-releasing hormone (GnRH) analogs, such as leuprolide, in a continuous-release formulation, may protect the ovaries from the gonadotoxic effects of chemotherapy. In non-HSCT settings, GnRH analogs have reduced the risk for premature ovarian failure to <10%. We conducted a phase II clinical trial based on the hypothesis that giving leuprolide before conditioning chemotherapy in HSCT patients reduces premature ovarian failure incidence.

Patients and Methods.

Eligible patients were women aged ≤40 years who were HSCT candidates, were premenopausal, and had both follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels ≤20 IU/L. Two 22.5-mg leuprolide doses were delivered in 3-month depot i.m. injections, the first within 2 months before HSCT. Patients were monitored for menstruation return, and ovarian function tests (FSH, LH, and estradiol) were done every 2 months starting 90 days after the last leuprolide dose.

Results.

Sixty eligible patients were enrolled, 59 underwent HSCT, and 44 were evaluable (median age, 25 years; median follow-up, 355 days). Only seven of 44 patients (16%) regained ovarian function. Of the 33 who received myeloablative regimens, six (18%) regained ovarian function. However, among the 11 who received nonmyeloablative regimens, only one (9%) regained ovarian function (p = .66).

Conclusion.

Leuprolide did not preserve ovarian function in patients who underwent HSCT using either myeloablative or nonmyeloablative regimens. Other measures that protect ovarian function need to be investigated.
Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone with or Without Radiotherapy in Primary Mediastinal Large B-Cell Lymphoma: The Emerging Standard of Care
Authors: Vassilakopoulos Theodoros P. , Pangalis Gerassimos A. , Katsigiannis Andreas , Papageorgiou Sotirios G. , Constantinou Nikos , Terpos Evangelos , Zorbala Alexandra , Vrakidou Effimia , Repoussis Panagiotis , Poziopoulos Christos , Galani Zacharoula , Dimopoulou Maria N. , Kokoris Stella I. , Sachanas Sotirios , Kalpadakis Christina , Dimitriadou Evagelia M. , Siakantaris Marina P. , Kyrtsonis Marie-Christine , Dervenoulas John , Dimopoulos Meletios A. , Meletis John , Roussou Paraskevi , Panayiotidis Panayiotis , Beris Photis , Angelopoulou Maria K.
Published: January 2012

Learning Objectives

After completing this course, the reader will be able to: Describe the effect of the addition of rituximab to standard CHOP chemotherapy on the outcome of patients with primary mediastinal large B-cell lymphoma.Explain potential changes in the use of radiotherapy and aggressive chemotherapy in the rituximab era.

This article is available for continuing medical education credit at CME.TheOncologist.com

More aggressive treatment approaches (methotrexate, cytarabine, cyclophosphamide, vincristine, prednisone, and bleomycin [the MACOP-B regimen] or consolidation with high-dose therapy and autologous stem cell transplantation) have been considered to be superior to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in patients with primary mediastinal large B-cell lymphoma (PMLBCL). Rituximab-CHOP (R-CHOP) is the standard of care for diffuse large B-cell lymphoma, whereas efficacy in PMLBCL has not been adequately confirmed.

Patient and Methods.

Seventy-six consecutive PMLBCL patients who received R-CHOP with or without radiotherapy (RT) were compared with 45 consecutive historical controls treated with CHOP with or without RT. Baseline characteristics of the two groups were balanced.

Results.

The rate of early treatment failure was much lower with R-CHOP with or without RT (9% versus 30%; p = .004). The 5-year freedom from progression rate after R-CHOP with or without RT was 81%, versus 48% for CHOP with or without RT (p < .0001). The 5-year event-free survival rates were 80% and 47% (p < .0001) and the 5-year overall and lymphoma-specific survival rates were 89% and 69% (p = .003) and 91% and 69% (p = .001), respectively, with only seven of 76 lymphoma-related deaths. Among R-CHOP responders, 52 of 68 received RT.

Conclusions.

Based on these results, most patients with PMLBCL appear to be cured by R-CHOP in 21-day cycles with or without RT, which could be the current standard of care. Therefore, the need for more aggressive treatment strategies is questionable unless high-risk patients are adequately defined. Further studies are required to establish the precise role of RT.
Long-Term Kidney Allograft Function and Survival in Prednisone-Free Regimens
Authors: Chhabra Darshika , Skaro Anton I. , Leventhal Joseph R. , Dalal Pranav , Shah Gaurav , Wang Edward , Gallon Lorenzo
Published: January 2012

Background and objectives

The optimal maintenance immunosuppressive regimen to improve long-term renal allograft function and graft survival is yet to be determined.

Design, setting, participants, & measurements

This observational study prospectively compared tacrolimus/sirolimus with tacrolimus/mycophenolate mofetil in renal transplant recipients using a prednisone-free regimen with over 8.5 years of follow-up. Patients received methylprednisonlone and anti-IL2 receptor antagonist (Basiliximab) induction and were blindly randomized to either the tacrolimus/mycophenolate mofetil (n=45) or tacrolimus/sirolimus (n=37) groups. Outcome measures included patient and renal allograft survival, incidence of acute rejection, and estimated GFR.

Results

The tacrolimus/mycophenolate mofetil group compared with the tacrolimus/sirolimus group had overall better renal allograft survival (91% versus 70%, P=0.02); 13 patients (35.1%) in the tacrolimus/sirolimus group and 8 patients (17.8%) in the tacrolimus/mycophenolate mofetil group experienced biopsy-proven acute cellular rejection (P=0.07). By 3 months post-transplant, estimated GFR was significantly lower in the tacrolimus/sirolimus group compared with the tacrolimus/mycophenolate mofetil group (47.7 versus 59.6 ml/min per 1.73 m2, P=0.0002), and this trend persisted throughout the follow-up period. Also, the slope of decline in the tacrolimus/sirolimus group was significantly steeper than in the tacrolimus/mycophenolate mofetil group.

Conclusions

This study shows that, in a prednisone-free immunosuppressive regimen, long-term renal graft survival and function are significantly worse in the tacrolimus/sirolimus group than the tacrolimus/mycophenolate mofetil group. The synergistic nephrotoxic effect and higher acute rejection rates in the tacrolimus/sirolimus compared with the tacrolimus/mycophenolate mofetil group adversely affect graft survival.
Pharmacokinetics and Pharmacodynamics of Piperacillin-Tazobactam in 42 Patients Treated with Concomitant CRRT
Authors: Bauer Seth R. , Salem Charbel , Connor Michael J. , Groszek Joseph , Taylor Maria E. , Wei Peilin , Tolwani Ashita J. , Fissell William H.
Published: January 2012

Background and objectives

Current recommendations for piperacillin-tazobactam dosing in patients receiving continuous renal replacement therapy originate from studies with relatively few patients and lower continuous renal replacement therapy doses than commonly used today. This study measured the pharmacokinetic and pharmacodynamic characteristics of piperacillin-tazobactam in patients treated with continuous renal replacement therapy using contemporary equipment and prescriptions.

Design, setting, participants, & measurements

A multicenter prospective observational study in the intensive care units of two academic medical centers was performed, enrolling patients with AKI or ESRD receiving piperacillin-tazobactam while being treated with continuous renal replacement therapy. Pregnant women, children, and patients with end stage liver disease were excluded from enrollment. Plasma and continuous renal replacement therapy effluent samples were analyzed for piperacillin and tazobactam levels using HPLC. Pharmacokinetic and pharmacodynamic parameters were calculated using standard equations. Multivariate analyses were used to examine the association of patient and continuous renal replacement therapy characteristics with piperacillin pharmacokinetic parameters.

Results

Forty-two of fifty-five subjects enrolled had complete sampling. Volume of distribution (median=0.38 L/kg, intraquartile range=0.20 L/kg) and elimination rate constants (median=0.104 h−1, intraquartile range=0.052 h−1) were highly variable, and clinical parameters could explain only a small fraction of the large variability in pharmacokinetic parameters. Probability of target attainment for piperacillin was 83% for total drug but only 77% when the unbound fraction was considered.

Conclusions

There is significant patient to patient variability in pharmacokinetic/pharmacodynamic parameters in patients receiving continuous renal replacement therapy. Many patients did not achieve pharmacodynamic targets, suggesting that therapeutic drug monitoring might optimize therapy.
Incidence and Progression of Diabetic Retinopathy During 17 Years of a Population-Based Screening Program in England
Authors: Jones Colin D. , Greenwood Richard H. , Misra Aseema , Bachmann Max O.
Published: January 2012

OBJECTIVE

To estimate the incidence of diabetic retinopathy in relation to retinopathy grade at first examination and other prognostic characteristics.

RESEARCH DESIGN AND METHODS

This was a dynamic cohort study of 20,686 people with type 2 diabetes who had annual retinal photography up to 14 times between 1990 and 2006. Cumulative and annual incidence rates were estimated using life tables, and risk factors for progression were identified using Cox regression analysis.

RESULTS

Of 20,686 patients without proliferative diabetic retinopathy (PDR) or sight-threatening maculopathy at their first retinal examination (baseline), 16,444 (79%) did not have retinopathy, 3,632 (18%) had nonproliferative retinopathy, and 610 (2.9%) had preproliferative retinopathy. After 5 years, few patients without retinopathy at baseline developed preproliferative retinopathy (cumulative incidence 4.0%), sight-threatening maculopathy (0.59%), or PDR (0.68%); after 10 years, the respective cumulative incidences were 16.4, 1.2, and 1.5%. Among those with nonproliferative (background) retinopathy at baseline, after 5 years 23% developed preproliferative retinopathy, 5.2% developed maculopathy, and 6.1% developed PDR; after 10 years, the respective cumulative incidences were 53%, 9.6%, and 11%. Patients with nonproliferative retinopathy at baseline were five times more likely to develop preproliferative, PDR, or maculopathy than those without retinopathy at baseline (adjusted hazard ratio 5.0 [95% CI 4.4–5.6]).

CONCLUSIONS

Few patients without diabetic retinopathy at the initial screening examination developed preproliferative retinopathy, PDR, or sight-threatening maculopathy after 5–10 years of follow-up. Screening intervals longer than a year may be appropriate for such patients.
Helicobacter pylori Infection Is Associated With an Increased Rate of Diabetes
Authors: Jeon Christie Y. , Haan Mary N. , Cheng Caroline , Clayton Erin R. , Mayeda Elizabeth R. , Miller Joshua W. , Aiello Allison E.
Published: January 2012

OBJECTIVE

Chronic infections could be contributing to the socioeconomic gradient in chronic diseases. Although chronic infections have been associated with increased levels of inflammatory cytokines and cardiovascular disease, there is limited evidence on how infections affect risk of diabetes.

RESEARCH DESIGN AND METHODS

We examined the association between serological evidence of chronic viral and bacterial infections and incident diabetes in a prospective cohort of Latino elderly. We analyzed data on 782 individuals aged >60 years and diabetes-free in 1998–1999, whose blood was tested for antibodies to herpes simplex virus 1, varicella virus, cytomegalovirus, Helicobacter pylori, and Toxoplasma gondii and who were followed until June 2008. We used Cox proportional hazards regression to estimate the relative incidence rate of diabetes by serostatus, with adjustment for age, sex, education, cardiovascular disease, smoking, and cholesterol levels.

RESULTS

Individuals seropositive for herpes simplex virus 1, varicella virus, cytomegalovirus, and T. gondii did not show an increased rate of diabetes, whereas those who were seropositive for H. pylori at enrollment were 2.7 times more likely at any given time to develop diabetes than seronegative individuals (hazard ratio 2.69 [95% CI 1.10–6.60]). Controlling for insulin resistance, C-reactive protein and interleukin-6 did not attenuate the effect of H. pylori infection.

CONCLUSIONS

We demonstrated for the first time that H. pylori infection leads to an increased rate of incident diabetes in a prospective cohort study. Our findings implicate a potential role for antibiotic and gastrointestinal treatment in preventing diabetes.
Glycemic Response and Attainment of A1C Goals Following Newly Initiated Insulin Therapy for Type 2 Diabetes
Authors: Nichols Gregory A. , Kimes Teresa M. , Harp Joyce B. , Kou Tzuyung Doug , Brodovicz Kimberly G.
Published: January 2012

OBJECTIVE

To identify the characteristics associated with glycemic response to newly initiated insulin therapy.

RESEARCH DESIGN AND METHODS

We identified 1,139 type 2 diabetic patients who initiated insulin therapy between 1 January 2009 and 30 June 2010. Outcomes of interest were the proportion of patients achieving A1C <7% and mean change in A1C within 3–9 months.

RESULTS

Mean A1C at insulin initiation was 8.2 vs. 9.2% among those who did and did not attain A1C <7% (P < 0.001). Within a mean of 5 months, 464 (40.7%) patients attained A1C <7%. In multivariable analyses controlling for insulin regimen, dose, and oral agent use, preinsulin A1C was responsible for nearly all the explained variance in A1C change. Each one percentage point of preinsulin A1C reduced the probability of attaining <7% by 26% (odds ratio 0.74 [95% CI 0.68–0.80]).

CONCLUSIONS

Insulin initiation at lower levels of A1C improves goal attainment and independently increases glycemic response.
Age Before Stage: Insulin Resistance Rises Before the Onset of Puberty
Authors: Jeffery Alison N. , Metcalf Brad S. , Hosking Joanne , Streeter Adam J. , Voss Linda D. , Wilkin Terence J.
Published: January 2012

OBJECTIVE

Insulin resistance (IR) is associated with diabetes. IR is higher during puberty in both sexes, with some studies showing the increase to be independent of changes in adiposity. Few longitudinal studies have reported on children, and it remains unclear when the rise in IR that is often attributed to puberty really begins. We sought to establish from longitudinal data its relationship to pubertal onset, and interactions with age, sex, adiposity, and IGF-1.

RESEARCH DESIGN AND METHODS

The EarlyBird Diabetes study is a longitudinal prospective cohort study of healthy children aged 5–14 years. Homeostasis model assessment (HOMA-IR), skinfolds (SSF), adiposity (percent fat, measured by dual-energy X-ray absorptiometry), serum leptin, and IGF-1 were measured annually in 235 children (134 boys). Pubertal onset was adduced from Tanner stage (TS) and from the age at which luteinizing hormone (LH) first became serially detectable (≥0.2 international units/L).

RESULTS

IR rose progressively from age 7 years, 3–4 years before TS2 was reached or LH became detectable. Rising adiposity and IGF-1 together explained 34% of the variance in IR in boys and 35% in girls (both P < 0.001) over the 3 years preceding pubertal onset. The contribution of IGF-1 to IR was greater in boys, despite their comparatively lower IGF-1 levels.

CONCLUSIONS

IR starts to rise in mid-childhood, some years before puberty. Its emergence relates more to the age of the child than to pubertal onset. More than 60% of the variation in IR prior to puberty was unexplained. The demography of childhood diabetes is changing, and prepubertal IR may be important.
Early Increase in Blood Glucose in Patients Resuscitated From Out-of-Hospital Ventricular Fibrillation Predicts Poor Outcome
Authors: Nurmi Jouni , Boyd James , Anttalainen Niko , Westerbacka Jukka , Kuisma Markku
Published: January 2012

OBJECTIVE

To describe the trend of blood glucose immediately after successful resuscitation from out-of-hospital ventricular fibrillation.

RESEARCH DESIGN AND METHODS

Data from cardiac arrest registry supplemented with blood glucose data were analyzed in this population-based observational study. Between 2005 and 2009, a total of 170 adult patients survived to hospital admission after resuscitation from bystander-witnessed cardiac arrest of cardiac origin and ventricular fibrillation as an initial rhythm.

RESULTS

Sufficient data for analysis were available in 134 (79%) patients, of whom 87 (65% [95% CI 57–73]) survived to hospital discharge in Cerebral Performance Category 1 or 2. Blood glucose did not change significantly between prehospital (10.5 ± 4.1 mmol/L) and admission (10.0 ± 3.7 mmol/L) in survivors (P = 0.3483), whereas in nonsurvivors, blood glucose increased from 11.8 ± 4.6 to 13.8 ± 3.3 mmol/L (P = 0.0025).

CONCLUSIONS

Patients who are resuscitated from out-of-hospital ventricular fibrillation, but whose outcome is unfavorable are characterized by significant increase of blood glucose in the ultraacute postresuscitation phase.
Effects of Electronegative VLDL on Endothelium Damage in Metabolic Syndrome
Authors: Chen Chu-Huang , Lu Jonathan , Chen Shu-Hua , Huang Roger Y. , Yilmaz H. Ramazan , Dong Jianwen , Elayda MacArthur A. , Dixon Richard A.F. , Yang Chao-Yuh
Published: January 2012

OBJECTIVE

Biochemical heterogeneity governs functional disparities among lipoproteins. We examined charge-defined VLDL subfractions in metabolic syndrome (MetS) to determine whether their increased electronegativity is associated with increased cytotoxicity and whether high concentrations of highly electronegative subfractions render VLDL harmful to the vascular endothelium.

RESEARCH DESIGN AND METHODS

Plasma VLDL of normal individuals (control subjects) (n = 13) and of those with MetS (n = 13) was resolved into subfractions with increasing negative charge (V1–V5) by anion-exchange chromatography. Human aortic endothelial cells were treated with V1–V5 or unfractionated VLDL.

RESULTS

Compared with the control subjects, individuals with MetS had a significantly higher percentage of V5 VLDL (V5/VLDL%) (34 ± 20 vs. 39 ± 11%, respectively; P < 0.05) and plasma V5 concentration ([V5]) (5.5 ± 4.4 vs. 15.2 ± 8.5 mg/dL, respectively; P < 0.001). Apolipoprotein (apo)B100 levels decreased and apoC levels increased from V1 to V5, indicating that V5 is apoC-rich VLDL. Regression analyses of all 26 individuals showed that [V5] was positively correlated with total cholesterol (P = 0.016), triglyceride (P < 0.000001), and V5/VLDL% (P = 0.002). Fasting plasma glucose, but not waist circumference, exhibited a positive trend (P = 0.058); plasma HDL cholesterol exhibited a weak inverse trend (P = 0.138). V5 (10 μg/mL) induced apoptosis in ~50% of endothelial cells in 24 h. V5 was the most rapidly (<15 min) internalized subfraction and induced the production of reactive oxygen species (ROS) in endothelial cells after 20 min. Unfractionated MetS VLDL, but not control VLDL, also induced ROS production and endothelial cell apoptosis.

CONCLUSIONS

In populations with increased risk of diabetes, the vascular endothelium is constantly exposed to VLDL that contains a high proportion of V5. The potential impact of V5-rich VLDL warrants further investigation.
Prediction at First Year of Incident New-Onset Diabetes After Kidney Transplantation by Risk Prediction Models
Authors: Rodrigo Emilio , Santos Lidia , Piñera Celestino , Ruiz San Millán Juan Carlos , Quintela Maria Estrella , Toyos Carmen , Allende Natalia , Gómez-Alamillo Carlos , Arias Manuel
Published: January 2012

OBJECTIVE

Our aim was to analyze the performance of two scores developed for predicting diabetes in nontransplant populations for identifying kidney transplant recipients with a higher new-onset diabetes mellitus after transplantation (NODAT) risk beyond the first year after transplantation.

RESEARCH DESIGN AND METHODS

We analyzed 191 kidney transplants, which had at least 1-year follow-up posttransplant. First-year posttransplant variables were collected to estimate the San Antonio Diabetes Prediction Model (SADPM) and Framingham Offspring Study–Diabetes Mellitus (FOS-DM) algorithm.

RESULTS

Areas under the receiver operating characteristic curve of FOS-DM and SADPM scores to predict NODAT were 0.756 and 0.807 (P < 0.001), respectively. FOS-DM and SADPM scores over 75 percentile (hazard ratio 5.074 and 8.179, respectively, P < 0.001) were associated with NODAT.

CONCLUSIONS

Both scores can be used to identify kidney recipients at higher risk for NODAT beyond the first year. SADPM score detects some 25% of kidney transplant patients with an eightfold risk for NODAT.
Transitive conformal holonomy groups
Authors: Alt Jesse
Published: January 2012

For (M, [g]) a conformal manifold of signature (p, q) and dimension at least three, the conformal holonomy group Hol(M, [g]) ⊂ O(p + 1, q + 1) is an invariant induced by the canonical Cartan geometry of (M, [g]). We give a description of all possible connected conformal holonomy groups which act transitively on the Möbius sphere S
p,q, the homogeneous model space for conformal structures of signature (p, q). The main part of this description is a list of all such groups which also act irreducibly on ℝp+1,q+1. For the rest, we show that they must be compact and act decomposably on ℝp+1,q+1, in particular, by known facts about conformal holonomy the conformal class [g] must contain a metric which is either Einstein (if p = 0 or q = 0) or locally isometric to a so-called special Einstein product.
Maintenance of rat hepatocytes under inflammation by coculture with human orbital fat-derived stem cells
Authors: Chen Xia , Zhang Shichang , Liu Tao , Liu Yong , Wang Yingjie
Published: January 2012

Preservation of hepatocyte functions in vitro will undoubtedly help the management of acute liver failure. The coculture system may be able to prevent functional decline of hepatocytes. It has already been shown that hepatocytes, when cocultured with bone marrow mesenchymal stem cells, could undergo long-term culture in vitro without loss of functions. In this study, human orbital fat-derived stem cells were isolated and cocultured with rat hepatocytes. When treated with serum from an acute liver failure patient, rat hepatocyte monoculture showed reduction of cell viability and loss of liverspecific functions. However, rat hepatocytes in the coculture system were still able to secret albumin and synthesize urea. IL-6 was significantly elevated in the coculture of rat hepatocyte with orbital fat-derived stem cells, and it might be the key immunoregulator which protects rat hepatocytes against inflammation. Our data confirmed that orbital fat-derived stem cells, or other adipose tissue-derived stem cells, are an ideal candidate to support rat hepatocyte functions in vitro.
Selective synthesis of E-isomers of aldoximes via a domino aza-Michael/retro-Michael reaction
Authors: Chen Wei , Yu Wei-Guo , Shi Hai-Bo , Lu Xiao-Yan
Published: January 2012

A highly stereoselective synthesis of E-isomer of aldoximes was developed through a base-catalysed domino aza-Michael/retro-Michael reaction of hydroxylamine and 2-(R-benzylidene)malononitrile. This reaction generates (E)-aldoxime diastereomer in high yields (eight examples, isolated yields of 82-93 %), excellent diastereomeric purity (diastereomeric ratio higher than 95: 5 by 1H NMR), and proceeds under mild reaction conditions (aqueous NaOH, pH 12, room temperature, 4 h).
Building an accurate 3D model of a circular feature for robot vision
Authors: Li L.
Published: January 2012

In this paper, an accurate 3D model analysis of a circular feature is built with error compensation for robot vision. We propose an efficient method of fitting ellipses to data points by minimizing the algebraic distance subject to the constraint that a conic should be an ellipse and solving the ellipse parameters through a direct ellipse fitting method by analysing the 3D geometrical representation in a perspective projection scheme, the 3D position of a circular feature with known radius can be obtained. A set of identical circles, machined on a calibration board whose centres were known, was calibrated with a camera and did the model analysis that our method developed. Experimental results show that our method is more accurate than other methods.
Steganographic data hiding in image processing using predictive differencing
Authors: Weng C. , Tso H. , Wang S.
Published: January 2012

In this paper, we propose a stenography scheme based on predictive differencing to embed data in a grey-image. In order to promote the embedding capacity of pixel-value differencing (PVD), we use differencing between a predictive value and an input pixel as the predictive differencing to embed the message where a predictive value is calculated by using various predictors. If the predictive differencing is large, then it means that the input pixel is located in the edge area and, thus, has a larger embedding capacity than the pixel in a smooth area. The experimental result shows that our proposed scheme is capable of providing greater embedding capacity and high quality of stego-images then previous works. Furthermore, we have also applied various predictors to evaluate our proposed scheme.
Investigating improvements to neural network based EMG to joint torque estimation
Authors: Chandrapal Mervin , Chen XiaoQi , Wang WenHui , Stanke Benjamin , Le Pape Nicolas
Published: January 2012

Although surface electromyography (sEMG) has a high correlation to muscle force, an accurate model that can estimate joint torque from sEMG is still elusive. Artificial neural networks (NN), renowned as universal approximators, have been employed to capture this complex nonlinear relation. This work focuses on investigating possible improvements to the NN methodology and algorithm that would consistently produce reliable sEMG-to-knee-joint torque mapping for any individual. This includes improvements in number of inputs, data normalization techniques, NN architecture and training algorithms. Data (sEMG) from five knee extensor and flexor muscle from one subject were recorded on 10 random days over a period of 3 weeks whilst subject performed both isometric and isokinetic movements. The results indicate that incorporating more muscles into the NN and normalizing the data at each isometric angle prior to NN training improves torque estimation. The mean lowest estimation error achieved for isometric motion was 10.461% (1.792), whereas the lowest estimation errors for isokinetic motion were larger than 20%.
Intensive Care Unit–Acquired Weakness: Implications for Physical Therapist Management
Authors: Nordon-Craft Amy , Moss Marc , Quan Dianna , Schenkman Margaret
Published: January 2012

Patients admitted to the intensive care unit (ICU) can develop a condition referred to as “ICU-acquired weakness.” This condition is characterized by profound weakness that is greater than might be expected to result from prolonged bed rest. Intensive care unit–acquired weakness often is accompanied by dysfunction of multiple organ systems. Individuals with ICU-acquired weakness typically have significant activity limitations, often requiring physical assistance for even the most basic activities associated with bed mobility. Many of these individuals have activity limitations months to years after hospitalization. The purpose of this article is to review evidence that guides physical rehabilitation of people with ICU-acquired weakness. Included are diagnostic criteria, medical management, and prognostic indicators, as well as criteria for beginning physical rehabilitation, with an emphasis on patient safety. Data are presented indicating that rehabilitation can be implemented with very few adverse effects. Evidence is provided for appropriate measurement approaches and for physical intervention strategies. Finally, some of the key issues are summarized that should be investigated to determine the best intervention guidelines for individuals with ICU-acquired weakness.
Can Supervised Group Exercises Including Ergonomic Advice Reduce the Prevalence and Severity of Low Back Pain and Pelvic Girdle Pain in Pregnancy? A Randomized Controlled Trial
Authors: Eggen Marit Horst , Stuge Britt , Mowinckel Petter , Jensen Kjersti Smee , Hagen Kåre Birger
Published: January 2012

Background

Many women have low back pain (LBP) or pelvic girdle pain (PGP) during pregnancy, but there is limited evidence of effective primary and secondary preventive strategies.

Objective

The purpose of this study was to investigate whether a group-based exercise program can reduce the prevalence and severity of LBP and PGP in pregnant women.

Design

An observer-blinded randomized controlled trial with equal assignments to a training group and a control group was conducted.

Setting

The study was conducted in primary care maternity units in 2 suburban municipalities in the southeastern part of Norway.

Patients

The participants were 257 pregnant women who were healthy and between 18 and 40 years of age before gestation week 20.

Intervention

The training group received supervised exercises in groups once a week, and the control group received standard care.

Measurements

The main outcome measures were self-reported LBP and self-reported PGP. Secondary outcome measures were pain intensity in the morning and evening, disability, and 8-Item Short-Form Health Survey (SF-8) Physical Component Summary (PCS) and Mental Component Summary (MCS) scores. Follow-up measurements were performed at gestation weeks 24, 28, 32, and 36.

Results

Overall, there was no effect of the program on the prevalence of PGP (odds ratio=1.03, 95% confidence interval [CI]=0.66 to 1.59) or LBP (odds ratio=0.77, 95% CI=0.50 to 1.19). For the secondary outcomes, the estimated mean differences between the groups were −0.4 (95% CI=−0.8 to 0.1) for pain intensity in the morning, −0.4 (95% CI=−1.0 to 0.2) for pain intensity in the evening, −1.0 (95% CI=−2.2 to 0.0) for disability, 1.8 (95% CI=0.0 to 3.7) for the SF-8 PCS, and −0.6 (95% CI=−2.2 to 1.4) for the SF-8 MCS.

Limitations

Due to low statistical power, the estimates for the primary outcomes are imprecise.

Conclusions

Supervised group exercise did not reduce the prevalence of LBP or PGP in pregnancy.
Responsiveness and Validity of the Six-Minute Walk Test in Individuals With Traumatic Brain Injury
Authors: Mossberg Kurt A. , Fortini Elizabeth
Published: January 2012

Background

A simple test of aerobic fitness for patients with traumatic brain injury (TBI) that is valid, reliable, and responsive to change is needed to provide clinicians a functional measure of cardiorespiratory capacity.

Objective

The purpose of this study was to examine the validity and responsiveness to change of the Six-Minute Walk Test (6MWT) in individuals with TBI.

Design

A cohort, pretest-posttest, comparison study was conducted.

Methods

Twenty-one patients performed the 6MWT upon admission to and prior to discharge from a postacute rehabilitation facility. Heart rate and distance traveled were recorded. A physiologic cost index (PCI) (beats per meter) was calculated based on steady-state heart rate. At discharge, all participants were able to perform a graded treadmill exercise test to exhaustion during which peak oxygen consumption (V̇o2) was measured.

Results

Between admission and discharge, mean total distance increased from 342.6 m (SD=127.0) to 408.9 m (SD=124.2), and work increased from 27,185 kg·m (SD=10,528) to 34,114 kg·m (SD=12,057). The effect size indexes were 1.10 and 1.12 for distance and work, respectively. Correlations (r) between the discharge peak V̇o2 and the discharge 6MWT distance, PCI, and work were .58, −.61, and .47, respectively.

Limitations

Stratification by gait speed may have improved responsiveness, especially for the slow ambulators.

Conclusions

All measures correlated well with peak V̇o2, establishing an acceptable level of criterion-related (concurrent) validity. The addition of heart rate and calculating the PCI was only slightly better at predicting peak V̇o2, albeit nonsignificant, than a simple measure of total distance. The 6MWT provides a good estimate of peak aerobic capacity, and some measures are more responsive to change than others in patients recovering from TBI.
Inspiratory Muscle Training in a Newborn With Anoxia Who Was Chronically Ventilated
Authors: Brunherotti Marisa Afonso Andrade , Bezerra Poliana Penasso , Bachur Cynthia Kallas , Jacometti Carlos Reis
Published: January 2012

Background and Purpose

Respiratory muscle training promotes weaning in patients who are dependent on mechanical ventilation. Respiratory muscles can be trained using linear inspiratory-resistive loads to improve their strength and endurance. The purpose of this case report is to demonstrate that a therapeutic intervention consisting of a linear pressure load device facilitates ventilator weaning in an infant who is chronically ventilated.

Case Description

The patient was a newborn with a weight of 4,725 g and an Apgar score of 0 to 1 who had been on mechanical ventilation for 8 months. Respiratory muscle training with a linear pressure load was performed twice a day. The number of series and repetitions was increased progressively while maintaining the pressure load, with 3-minute intervals between series, until reaching a peak of 8 series with 70 repetitions and a pressure load of 13 cm H2O. During the intervention, the patient was maintained in the supine position at an elevation of 30 degrees.

Outcomes

The infant required mechanical ventilation for 8 months (32 weeks of life), with 4,450 hours (26.5 weeks) of mechanical ventilation and 230 cumulative hours (1.4 weeks) of spontaneous breathing, without obtaining any weaning success. At 10 months of age (40 weeks) and after 2 months (8 weeks) of respiratory muscle training, the results were 490 hours (3 weeks) of mechanical ventilation and 854 hours (5 weeks) of spontaneous breathing. Complete independence of the infant from mechanical ventilation was achieved thereafter.

Discussion

This case report describes respiratory muscle training using a linear pressure load device to successfully wean an infant from mechanical ventilation. However, well-controlled clinical trials are necessary to better understand the effects of this intervention on neonatal respiratory muscles.
Establishment and characterization of a primary human chordoma xenograft model
Authors: Siu I-Mei , Salmasi Vafi , Orr Brent A. , Zhao Qi , Binder Zev A. , Tran Christine , Ishii Masaru , Riggins Gregory J. , Hann Christine L. , Gallia Gary L.
Published: January 2012

Object

Chordomas are rare tumors arising from remnants of the notochord. Because of the challenges in achieving a complete resection, the radioresistant nature of these tumors, and the lack of effective chemotherapeutics, the median survival for patients with chordomas is approximately 6 years. Reproducible preclinical model systems that closely mimic the original patient's tumor are essential for the development and evaluation of effective therapeutics. Currently, there are only a few established chordoma cell lines and no primary xenograft model. In this study, the authors aimed to develop a primary chordoma xenograft model.

Methods

The authors implanted independent tumor samples from 2 patients into athymic nude mice. The resulting xenograft line was characterized by histopathological analysis and immunohistochemical staining. The patient's tumor and serial passages of the xenograft were genomically analyzed using a 660,000 single-nucleotide polymorphism array.

Results

A serially transplantable xenograft was established from one of the 2 patient samples. Histopathological analysis and immunohistochemical staining for S100 protein, epithelial membrane antigen, and cytokeratin AE1/AE3 of the primary patient sample and the xenografts confirmed that the xenografts were identical to the original chordoma obtained from the patient. Immunohistochemical staining and western blot analysis confirmed the presence of brachyury, a recently described marker of chordomas, in the tumor from the patient and each of the xenografts. Genome-wide variation was assessed between the patient's tumor and the xenografts and was found to be more than 99.9% concordant.

Conclusions

To the best of their knowledge, the authors have established the first primary chordoma xenograft that will provide a useful preclinical model for this disease and a platform for therapeutic development.
In vivo intraoperative confocal microscopy for real-time histopathological imaging of brain tumors
Authors: Eschbacher Jennifer , Martirosyan Nikolay L. , Nakaji Peter , Sanai Nader , Preul Mark C. , Smith Kris A. , Coons Stephen W. , Spetzler Robert F.
Published: January 2012

Object

Frozen-section analysis is the current standard for the intraoperative diagnosis of brain tumors. Intraoperative confocal microscopy is an emerging technology with the potential to visualize tumor histopathological features and cell morphology in real time. The authors report their findings using this new intraoperative technology in vivo with sodium fluorescein contrast during the course of 50 microsurgical tumor resections.

Methods

Eighty-eight regions were visualized with confocal microscopy, and corresponding biopsy samples were examined with routine neuropathological analysis. The tumors studied included meningiomas, schwannomas, gliomas of various grades, and a hemangioblastoma. The confocal microscopic features of each tumor and of various artifacts inherent to the technology were documented. A pathologist working in a blinded fashion reviewed a subset of the images in a further evaluation of the usefulness of the device as a diagnostic tool.

Results

Overall, intraoperative confocal imaging correlated surprisingly well with corresponding traditional histological findings, including the identification of many pathognomonic cytoarchitectural features of various brain tumors. In the blinded study, 26 (92.9%) of 28 lesions were diagnosed correctly.

Conclusions

Further study will be necessary for better definition of the role of intraoperative confocal microscopy as a routine adjunct for intraoperative brain tumor diagnosis.
Indirect foraminal decompression after lateral transpsoas interbody fusion
Authors: Kepler Christopher K. , Sharma Amit K. , Huang Russel C. , Meredith Dennis S. , Girardi Federico P. , Cammisa Frank P. , Sama Andrew A.
Published: January 2012

Object

Lateral transpsoas interbody fusion (LTIF) permits anterior column lumbar interbody fusion via a direct lateral approach. The authors sought to answer 3 questions. First, what is the effect of LTIF on lumbar foraminal area? Second, how does interbody cage placement affect intervertebral height? And third, how does the change in foraminal area and cage position correlate with changes in Oswestry Disability Index (ODI) and 12-Item Short Form Health Survey (SF-12) scores?

Methods

Included patients underwent LTIF with or without posterior instrumentation and received preoperative and postoperative CT scans. Disc heights, neural foraminal area between adjacent-level pedicles, and anteroposterior cage position were measured from sagittal CT images. Preoperative and postoperative ODI and SF-12 scores were matched with the change in foraminal area from the clinically most severely affected side for analysis of the relationship between outcomes instruments and change in foraminal area.

Results

Average foraminal area increased by 36.2 mm2, or 35% of the preoperative area (p < 0.01), without statistically significant differences by side, level, or anteroposterior cage position. Preoperative anterior and posterior disc heights measured 6.2 mm and 3.7 mm, respectively, compared with postoperative measurements of 9.8 mm (p < 0.01) and 6.3 mm (p < 0.01), respectively, without significant differences by level or cage position. Despite significant overall improvement in ODI and SF-12 scores, there was no correlation with foraminal area increase.

Conclusions

Average foraminal area increased approximately 35% after cage placement without variation based on cage position. While ODI and SF-12 scores increased significantly, there was no significant association with cage position or foraminal area change, likely attributable to the multifactorial nature of preoperative pain.
The Potential for the Use of the Occupants’ Comments in the Analysis and Prediction of Building Performance
Authors: Baird George , Dykes Clare
Published: January 2012

The authors investigated the occupants’ perceptions of 47 commercial and institutional buildings worldwide. These investigations involved the personal distribution and collection of a questionnaire survey seeking the occupants' perceptions (scored on a 7-point scale) of some 45 factors: Operational; Environmental (including temperature, air quality, lighting, and noise); Personal Control; and Satisfaction (including design, needs, comfort overall, productivity, and health). Occupants were also invited to comment on nine of these factors. While it has been suggested that in the ideal situation the occupants would have no complaints about their indoor environment, the aim here was to discover the real situation—in particular the proportion of occupants who were prepared to make a comment, the general nature of the comments (positive, negative, or balanced), and whether these correlated with the occupants’ perception scores. On average, 34 per cent of respondents took up the invitation to make a comment. As anticipated, the greater the number of positive comments, the better the perception score, and vice-versa. However, it appears that it only required around 20% of the comments to be positive for the perception score to exceed the mid-point of the seven-point scale, whereas 65% or more of negative comments were needed to go under that point. This paper details the nature of the correlation between the occupants’ comments and the corresponding scores for a range of building operational and indoor environmental factors and speculates on their potential for the analysis and prediction of building performance from the perspective of the occupants.
Effect of Fiber Esterification on Fundamental Properties of Oil Palm Empty Fruit Bunch Fiber/Poly(butylene adipate-co-terephthalate) Biocomposites
Authors: Siyamak Samira , Ibrahim Nor Azowa , Abdolmohammadi Sanaz , Yunus Wan Md Zin Wan , Rahman Mohamad Zaki AB
Published: January 2012

A new class of biocomposites based on oil palm empty fruit bunch fiber and poly(butylene adipate-co-terephthalate) (PBAT), which is a biodegradable aliphatic aromatic co-polyester, were prepared using melt blending technique. The composites were prepared at various fiber contents of 10, 20, 30, 40 and 50 wt% and characterized. Chemical treatment of oil palm empty fruit bunch (EFB) fiber was successfully done by grafting succinic anhydride (SAH) onto the EFB fiber surface, and the modified fibers were obtained in two levels of grafting (low and high weight percentage gain, WPG) after 5 and 6 h of grafting. The FTIR characterization showed evidence of successful fiber esterification. The results showed that 40 wt% of fiber loading improved the tensile properties of the biocomposite. The effects of EFB fiber chemical treatments and various organic initiators content on mechanical and thermal properties and water absorption of PBAT/EFB 60/40 wt% biocomposites were also examined. The SAH-g-EFB fiber at low WPG in presence of 1 wt% of dicumyl peroxide (DCP) initiator was found to significantly enhance the tensile and flexural properties as well as water resistance of biocomposite (up to 24%) compared with those of untreated fiber reinforced composites. The thermal behavior of the composites was evaluated from thermogravimetric analysis (TGA)/differential thermogravimetric (DTG) thermograms. It was observed that, the chemical treatment has marginally improved the biocomposites’ thermal stability in presence of 1 wt% of dicumyl peroxide at the low WPG level of grafting. The improved fiber-matrix surface enhancement in the chemically treated biocomposite was confirmed by SEM analysis of the tensile fractured specimens.
MetastamiRs: Non-Coding MicroRNAs Driving Cancer Invasion and Metastasis
Authors: Lopez-Camarillo Cesar , Marchat Laurence A. , Arechaga-Ocampo Elena , Perez-Plasencia Carlos , Moral-Hernandez Oscar del , Castaneda-Ortiz Elizabeth J. , Rodriguez-Cuevas Sergio
Published: January 2012

MicroRNAs (miRNAs) are small non-coding RNAs of ~22 nucleotides that function as negative regulators of gene expression by either inhibiting translation or inducing deadenylation-dependent degradation of target transcripts. Notably, deregulation of miRNAs expression is associated with the initiation and progression of human cancers where they act as oncogenes or tumor suppressors contributing to tumorigenesis. Abnormal miRNA expression may provide potential diagnostic and prognostic tumor biomarkers and new therapeutic targets in cancer. Recently, several miRNAs have been shown to initiate invasion and metastasis by targeting multiple proteins that are major players in these cellular events, thus they have been denominated as metastamiRs. Here, we present a review of the current knowledge of miRNAs in cancer with a special focus on metastamiRs. In addition we discuss their potential use as novel specific markers for cancer progression.
Le commerce coopératif en France : du progrès à la crise
Authors: Soumagne Jean
Published: January 2012

Le secteur commercial coopératif a subi une érosion brutale en 1985-1986 qui l'a privé d'une partie de ses sociétés régionales et de beaucoup de magasins modernes, les éléments subsistants étant contraints de s'affilier à des centrales d'achat extérieures et, souvent, d'adopter leurs enseignes. Cette crise aiguë a révélé les faiblesses du mouvement coopératif, issues de son histoire et de son idéologie, de la diversité des réponses de structures régionales trop éclatées au défi de la modernisation de l'appareil de vente.
Les mouvements de population dans l'arrondissement de Limoges
Authors: Pallier Ginette
Published: January 2012

From 1968 to 1982 the population of the « arrondissement » of Limoges has increased, but very irregularly. Apart from some of their main towns, the population of rural « cantons » has fallen whilst that of the suburban « cantons » has increased.

The determining factor has been that immigration has outpaced emigration. The population of the most rural parishes has diminished in favour of the résidentiel parishes close to Limoges whilst the situation of those further out has remained stable. Limoges is a pole of attraction for the people coming from the country and who live preferably in the immediate suburbs.