bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scheuermann’s kyphosis; current controversies
Authors: Tsirikos A. I. , Jain A. K. 
Published: June 2011

This review of the literature presents the current understanding of Scheuermann’s kyphosis and investigates the controversies concerning conservative and surgical treatment. There is considerable debate regarding the pathogenesis, natural history and treatment of this condition. A benign prognosis with settling of symptoms and stabilisation of the deformity at skeletal maturity is expected in most patients. Observation and programmes of exercise are appropriate for mild, flexible, non-progressive deformities. Bracing is indicated for a moderate deformity which spans several levels and retains flexibility in motivated patients who have significant remaining spinal growth. The loss of some correction after the completion of bracing with recurrent anterior vertebral wedging has been reported in approximately one-third of patients. Surgical correction with instrumented spinal fusion is indicated for a severe kyphosis which carries a risk of progression beyond the end of growth causing cosmetic deformity, back pain and neurological complications. There is no consensus on the effectiveness of different techniques and types of instrumentation. Techniques include posterior-only and combined anteroposterior spinal fusion with or without posterior osteotomies across the apex of the deformity. Current instrumented techniques include hybrid and all-pedicle screw constructs.
The Andersson lesion in ankylosing spondylitis
Authors: Park Y.-S. , Kim J.-H. , Ryu J.-A. , Kim T.-H. 
Published: June 2011

A number of causes have been advanced to explain the destructive discovertebral (Andersson) lesions that occur in ankylosing spondylitis, and various treatments have been proposed, depending on the presumed cause. The purpose of this study was to identify the causes of these lesions by defining their clinical and radiological characteristics. We retrospectively reviewed 622 patients with ankylosing spondylitis. In all, 33 patients (5.3%) had these lesions, affecting 100 spinal segments. Inflammatory lesions were found in 91 segments of 24 patients (3.9%) and traumatic lesions in nine segments of nine patients (1.4%). The inflammatory lesions were associated with recent-onset disease; a low modified Stoke ankylosing spondylitis spine score (mSASSS) due to incomplete bony ankylosis between vertebral bodies; multiple lesions; inflammatory changes on MRI; reversal of the inflammatory changes and central bony ankylosis at follow-up; and a good response to anti-inflammatory drugs. Traumatic lesions were associated with prolonged disease duration; a high mSASSS due to complete bony ankylosis between vertebral bodies; a previous history of trauma; single lesions; nonunion of fractures of the posterior column; acute kyphoscoliotic deformity with the lesion at the apex; instability, and the need for operative treatment due to that instability. It is essential to distinguish between inflammatory and traumatic Andersson lesions, as the former respond to medical treatment whereas the latter require surgery.
Is a fracture of the transverse process of L5 a predictor of pelvic fracture instability?
Authors: Starks I. , Frost A. , Wall P. , Lim J. 
Published: June 2011

In the management of a pelvic fracture prompt recognition of an unstable fracture pattern is important in reducing mortality and morbidity. It is believed that a fracture of the transverse process of L5 is a predictor of pelvic fracture instability. However, there is little evidence in the literature to support this view. The aim of this study was to determine whether a fracture of the transverse process of L5 is a reliable predictor of pelvic fracture instability. We reviewed our hospital trauma database and identified 80 patients who sustained a pelvic fracture between 2006 and 2010. There were 32 women and 48 men with a mean age of 40 years (10 to 96). Most patients were injured in a road traffic accident or as a result of a fall from a height. A total of 41 patients (51%) had associated injuries. The pelvic fractures were categorised according to the Burgess and Young classification. There were 45 stable and 35 unstable fractures. An associated fracture of the transverse process of L5 was present in 17 patients; 14 (40%) of whom had an unstable fracture pattern. The odds ratio for an unstable fracture of the pelvis in the presence of a fracture of the transverse process of L5 was 9.3 and the relative risk was 2.5. A fracture of the transverse process of L5 in the presence of a pelvic fracture is associated with an increased risk of instability of the pelvic fracture. Its presence should alert the attending staff to this possibility.
A Flexible Estimating Equations Approach for Mapping Function-Valued Traits
Authors: Xiong Hao , Goulding Evan H , Carlson Elaine J , Tecott Laurence H , McCulloch Charles E , Sen Śaunak 
Published: June 2011

AbstractIn genetic studies, many interesting traits, including growth curves and skeletal shape, have temporal or spatial structure. They are better treated as curves or function-valued traits. Identification of genetic loci contributing to such traits is facilitated by specialized methods that explicitly address the function-valued nature of the data. Current methods for mapping function-valued traits are mostly likelihood-based, requiring specification of the distribution and error structure. However, such specification is difficult or impractical in many scenarios. We propose a general functional regression approach based on estimating equations that is robust to misspecification of the covariance structure. Estimation is based on a two-step least-squares algorithm, which is fast and applicable even when the number of time points exceeds the number of samples. It is also flexible due to a general linear functional model; changing the number of covariates does not necessitate a new set of formulas and programs. In addition, many meaningful extensions are straightforward. For example, we can accommodate incomplete genotype data, and the algorithm can be trivially parallelized. The framework is an attractive alternative to likelihood-based methods when the covariance structure of the data is not known. It provides a good compromise between model simplicity, statistical efficiency, and computational speed. We illustrate our method and its advantages using circadian mouse behavioral data.
The Joint Effects of Background Selection and Genetic Recombination on Local Gene Genealogies
Authors: Zeng Kai , Charlesworth Brian 
Published: June 2011

AbstractBackground selection, the effects of the continual removal of deleterious mutations by natural selection on variability at linked sites, is potentially a major determinant of DNA sequence variability. However, the joint effects of background selection and genetic recombination on the shape of the neutral gene genealogy have proved hard to study analytically. The only existing formula concerns the mean coalescent time for a pair of alleles, making it difficult to assess the importance of background selection from genome-wide data on sequence polymorphism. Here we develop a structured coalescent model of background selection with recombination and implement it in a computer program that efficiently generates neutral gene genealogies for an arbitrary sample size. We check the validity of the structured coalescent model against forward-in-time simulations and show that it accurately captures the effects of background selection. The model produces more accurate predictions of the mean coalescent time than the existing formula and supports the conclusion that the effect of background selection is greater in the interior of a deleterious region than at its boundaries. The level of linkage disequilibrium between sites is elevated by background selection, to an extent that is well summarized by a change in effective population size. The structured coalescent model is readily extendable to more realistic situations and should prove useful for analyzing genome-wide polymorphism data.
Incidence of Clostridium difficile Infections in Patients Receiving Antimicrobial and Acid‐Suppression Therapy
Authors: King Rachel N. , Lager Stephanie L. 
Published: June 2011

Study Objectives. To determine the incidence of Clostridium difficile infection (CDI) at one community hospital by identifying patients with stool samples positive for C. difficile toxin A or B, and to compare the incidence with a 2008 national estimate; and to determine which patient characteristics and concomitant antimicrobial and acid‐suppression drugs are risk factors for the development of CDI.Design. Retrospective, single‐center, medical record review.Setting. 350‐bed community hospital.Patients. A total of 11,010 admissions between January 1, 2009, and December 31, 2009; 115 of these patients had stool samples positive for C. difficile toxin A or B.Measurements and Main Results. All C. difficile toxin A and B enzyme immunoassay tests were performed by a central laboratory. The incidence of CDI was 10.4 cases/1000 patient admissions, which was significantly lower than the overall incidence reported in a 2008 national survey of 13.1 CDI cases/1000 patient admissions (p=0.021). Demographic and clinical data of the patients with CDI were collected by using electronic medical records. Patients were more likely to be elderly and female, and to have developed CDI during hospitalization. Of the 115 patients, 95 (82.6%) received acid‐suppression therapy and 91 (79.1%) received antimicrobials. Of the patients receiving acid‐suppression therapy, 72 (75.8%) received a proton pump inhibitor during their hospitalization, and 49 (51.6%) received both a proton pump inhibitor and an antibiotic. The most frequently used antibiotics in this population were fluoroquinolones, cephalosporins, and carbapenems, with a significantly larger proportion of patients who received carbapenems developing CDI compared with the other classes of antibiotics (p<0.05 for both comparisons). Patients receiving antimicrobial and acid‐suppression therapy were more likely to develop CDI than those who did not receive these drugs.Conclusion. The incidence of CDI in 2009 at one community hospital was significantly lower than a 2008 national estimate. Antimicrobial and acid‐suppression therapies—in particular, combinations of fluoroquinolones, cephalosporins, carbapenems, and proton pump inhibitors—were found to be risk factors for the development of CDIs in hospitalized patients.
Dosing and Monitoring of Low‐Molecular‐Weight Heparin in High‐Risk Pregnancy: Single‐Center Experience
Authors: Shapiro Nancy L. , Kominiarek Michelle A. , Nutescu Edith A. , Chevalier Aimee B. , Hibbard Judith U. 
Published: June 2011

Study Objective. To evaluate dosing requirements and monitoring patterns of low‐molecular‐weight heparin (LMWH) when usedinhigh‐risk pregnancy.Design. Retrospective, observational, cohort study.Setting. University‐affiliated medical center.Patients. Forty‐nine women treated with LMWH between 2001 and 2005 for either prophylaxis or treatment of venous thromboembolism during pregnancy and monitored with antifactor Xa activity.Measurements and Main Results. Data were obtained on 53 pregnancies in the 49 women. The primary outcome was change in dosing requirements of LMWH throughout pregnancy as determined by the corresponding antifactor Xa activity peak levels. Mean starting doses of twice‐daily enoxaparin and doses most proximate to delivery were 39.2 mg (range 30–60 mg) and 55.0 mg (range 30–100 mg, p=0.06), respectively, for the prophylaxis group and 83.0 mg (range 30–180 mg) and 85.7 mg (range 30–160 mg, p=0.41), respectively, for the therapeutic group. Weight‐based mean starting doses and doses most proximate to delivery were 0.46 and 0.62 mg/kg (p=0.03), respectively, for the prophylaxis group and 0.90 and 0.87 mg/kg (p=0.29), respectively, for the therapeutic group. Dose changes were required in 9 (69%) of 13 pregnancies and 21 (55%) of 38 pregnancies (data from two of the 40 pregnancies were excluded—one in a patient receiving dalteparin, and one in a patient with mitral valve replacement who had higher antifactor Xa goals) in the prophylaxis and therapeutic groups, respectively, to achieve target antifactor Xa activity. The weight‐based prophylactic dose was consistently 0.6 mg/kg in all three trimesters, achieving a mean ± SD target antifactor Xa activity of 0.39 ± 0.18 units/ml, whereas the therapeutic dose was 0.9 mg/kg to maintain antifactor Xa activity of 0.71 ± 0.22 units/ml.Conclusion. Dose changes for LMWH throughout pregnancy as guided by antifactor Xa activity were common. A significant increase in the LMWH dose requirements in the prophylactic group suggests that more frequent monitoring of antifactor Xa activity may be appropriate in pregnant patients to maintain target anticoagulant levels.
Safety and Effectiveness of U‐500 Insulin Therapy in Patients with Insulin‐Resistant Type 2 Diabetes Mellitus
Authors: Quinn Suzanne L. , Lansang M. Cecilia , Mina Deanna 
Published: June 2011

Study Objective. To assess the safety and effectiveness of highly concentrated U‐500 regular insulin in patients with insulin‐resistant type 2 diabetes mellitus who were switched from U‐100 insulin.Design. Retrospective cohort study.Setting. Outpatient diabetes management clinic.Patients. Twenty‐one adults with poorly controlled type 2 diabetes and insulin resistance who were referred to the clinic between July 1, 2007, and June 30, 2008, and whose therapy was changed from large doses of U‐100 insulin to U‐500 insulin.Measurements and Main Results. Demographic and clinical data were collected through a computerized medical record system. Insulin resistance was defined as a requirement of more than 200 units/day of insulin and more than 100 units/injection. The primary outcome was the change in hemoglobin A1c (A1C) after switching from any type of U‐100 insulin to stabilization with U‐500 highly concentrated regular insulin. Secondary outcomes were the changes in number of daily insulin injections, daily insulin dose, and body weight. With use of U‐500 insulin, patients were able to achieve an average reduction in A1C of 1.7% (p<0.001). The mean number of daily injections decreased from 4.3 with U‐100 insulin to 2.7 after using U‐500 insulin (p<0.001), but changes in body weight after the change in insulin were not statistically significant (279.8 vs 279.2 lbs, p=0.429). No patient discontinued U‐500 insulin during the study, and none experienced hypoglycemia severe enough to require the assistance of another individual.Conclusion. In patients with insulin‐resistant diabetes who have requirements of more than 200 units/day or 100 units/injection, use of U‐500 regular insulin provided the same or better glucose control compared with U‐100 insulin, with fewer daily injections and reduced injection volume. Although this drug represents an excellent treatment option, its safe use requires an experienced physician, a motivated and cooperative patient, and a dynamic diabetes management team.
Current Targeted Therapies in Breast Cancer: Clinical Applications in the Elderly Woman
Authors: Spano Jean-Philippe , Falandry Claire , Chaibi Pascal , Freyer Gilles 
Published: June 2011

Abstract

Learning Objectives
After completing this course, the reader will be able to: Include geriatric assessment into oncologic practice to describe patients and to evaluate the real benefit/risk ratio of any adjuvant treatment.Describe the actual risk of association of erythropoiesis-stimulating agents with bevacizumab.
This article is available for continuing medical education credit at CME.TheOncologist.com
The incidence of breast cancer is two to three times higher in women aged ≥65 years than in the whole population, whereas their mortality rate is threefold to fourfold higher. Targeted therapies allow significantly longer disease-free survival times. Nevertheless, in an elderly population, these treatments need to be prescribed with caution. This paper reviews the treatments of breast cancer in the elderly, and the issues of targeted therapies and their toxicities.
Patients with human epidermal growth factor receptor (HER)-2+ breast cancer benefit from trastuzumab; although cardiotoxic effects are observed in &lt;5% of patients when given alone, they affect ∼25% of patients when combined with anthracyclines. Bevacizumab leads to a longer progression-free survival time and lower risk for progression in patients with metastatic breast cancer when added to paclitaxel or docetaxel. Although generally well tolerated, it is associated with a higher risk for arterial thromboembolism and hypertension. Lapatinib is approved for the treatment of advanced or metastatic breast cancer in patients not responding to trastuzumab, combined with capecitabine chemotherapy. The most frequent side effects concern the gastrointestinal system and dermatologic symptoms.
The life expectancy of breast cancer patients should be taken into account to determine the appropriateness of treatments. The quality of life of elderly cancer patients must be assessed with an appropriate tool. Older patients exhibit greater vulnerability, suggesting identification and exclusion of patients at high cardiac risk.
Future recommendations for the treatment of elderly women with breast cancer should include a multidisciplinary approach and a global geriatric assessment before treatment with anti–HER-2 therapy or bevacizumab.
Determination of Artificial Sweeteners in Beverages and Special Nutritional Products Using High Performance Liquid Chromatography
Authors: Serdar Maja , Knežević Zorka 
Published: June 2011

Determination of Artificial Sweeteners in Beverages and Special Nutritional Products Using High Performance Liquid ChromatographyThis paper presents two high performance liquid chromatographic (HPLC) methods used for the separation and determination of artificial sweeteners aspartame, acesulphame K, sodium saccharin, and sodium cyclamate in beverages and special nutritional products (special food intended for specific population groups). All four compounds are soluble in aqueous solutions and can easily be separated and determined by HPLC with a diode array detector (DAD). The first method involved separation of aspartame, acesulphame K, and sodium saccharin on a C18 column with an isocratic elution of phosphate buffer and acetonitrile as mobile phase. The second method was used to separate sodium cyclamate on a C18 column with methanol and water as mobile phase. Under optimum conditions, both methods showed good analytical performance, such as linearity, precision, and recovery. The methods were successfully applied for the analysis of real samples of soft drinks and special nutritional products.
Biomonitoring of Human Exposure to Triazine Herbicides
Authors: Mendaš Gordana 
Published: June 2011

Biološki Monitoring Izloženosti Ljudi Triazinskim Herbicidima Analizom Metabolita u UrinuTriazinski herbicidi jedni su od najčešće rabljenih herbicida. Sudbina triazinskih herbicida nakon dospijevanja u okoliš ovisi o njihovu kretanju u zraku, vodi i tlu, kao i o brzini kojom se razgrađuju ili transformiraju. Triazinski spojevi mogu se transformirati reakcijom s vodom, djelovanjem mikroorganizama i utjecajem Sunčeva svjetla. Široka i često nekontrolirana primjena triazinskih herbicida tijekom nekoliko proteklih desetljeća rezultirala je kontaminacijom pitke vode i hrane postajući rizik za opću populaciju. Metabolizam i djelovanje triazinskih herbicida proučavani su na pokusnim životinjama i u uvjetima in vitro, dok je o njihovu metabolizmu i izlučivanju kod ljudi malo objavljenih radova. Djelovanju triazinskih herbicida osobito su izloženi radnici zaposleni u njihovoj proizvodnji i primjeni. Izloženost ljudi prati se i dokazuje određivanjem izvornih spojeva i njihovih metabolita u urinu. Kako se triazinski spojevi u urinu profesionalno izloženih ljudi pojavljuju u niskim koncentracijama, za njihovo dokazivanje i praćenje profesionalne izloženosti potrebno je primijeniti analitičke metode visoke djelotvornosti, osjetljivosti i selektivnosti. U ovom radu opisani su struktura i svojstva simetričnih triazinskih herbicida, njihov metabolizam i djelovanje u organizmu čovjeka i životinja te razine metabolita tih spojeva određene u urinu ispitanika iz profesionalno izložene populacije.
Work Ability Assessment in a Patient with Wilson's Disease
Authors: Popević Martin , Kisić Gordana , Đukić Milenko , Bulat Petar 
Published: June 2011

Work Ability Assessment in a Patient with Wilson's DiseaseWilson's disease (WD) is a rare, progressive autosomal recessive disorder characterised by impaired transport and excessive accumulation of copper in the liver, brain, and other tissues. The disease is diagnosed based on clinical manifestations and screening tests results. Work ability assessment of patients with WD is based on the analysis of liver, kidney, neurological, and cognitive impairments, and takes into account patient's level of education.This article presents a case with a 48-year-old male patient, who was admitted for work ability assessment due to polymorphic symptoms. The patient had been working as a salesman for 28 years. A detailed interview and examination by occupational health and other medical specialists revealed that the patient had been suffering from Wilson's disease from the age of 13, and had now developed hepatic manifestations (compensated liver cirrhosis with portal hypertension), neurological manifestations (dystonia, dysarthria, muscle weakness, vertigo), and psychiatric manifestations (depression, insomnia, cognitive impairment) of the disease, including problems partially caused by long-lasting treatment with copper chelating agents (neurological and haematological manifestations). There were no ocular manifestations of Wilson's disease (Kayser-Fleischer rings or sunflower cataract).The patient was assessed as having drastically diminished general work ability, dominantly due to neurological and psychiatric impairments caused by Wilson's disease.
Cholinesterases: Structure, Role, and Inhibition
Authors: Bosak Anita , Katalinić Maja , Kovarik Zrinka 
Published: June 2011

Kolinesteraze: struktura, uloga, inhibicijaAcetilkolinesteraza (AChE; E.C. 3.1.1.7) i butirilkolinesteraza (BChE; E.C. 3.1.1.8) enzimi su koji se zbog svoje uloge u organizmu intenzivno istražuju unutar područja biomedicine i toksikologije. Iako strukturno homologni, ovi enzimi razlikuju se prema katalitičkoj aktivnosti, odnosno specifičnosti prema supstratima koje mogu hidrolizirati te selektivnosti za vezanje mnogih liganada. U ovom radu dan je pregled dosadašnjih istraživanja kolinesteraza i njihovih interakcija s ligandima i inhibitorima te su izdvojene aminokiseline aktivnog mjesta koje sudjeluju u tim interakcijama.