bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of 2 Surgical Techniques of Posterolateral Corner Reconstruction of the Knee
Authors: Nau Thomas , Chevalier Yan , Hagemeister Nicola , deGuise Jacques A. , Duval Nicolas 
Published: September 2005

Background Various surgical techniques to treat posterolateral knee instability have been described. To date, the recommended treatment is an anatomical form of reconstruction, in which the 3 key structures of the posterolateral corner are addressed: the lateral collateral ligament, the popliteofibular ligament, and the popliteus tendon. Hypothesis Two methods of surgical reconstruction will restore posterolateral knee instability, in terms of static laxity as well as dynamic 6 degrees of freedom kinematics, to statistically significant levels compared with the intact state. Study Design Controlled laboratory study. Methods Two surgical techniques (A and B) were used to reconstruct the posterolateral structures in 10 cadaveric knees. Static tests were performed on the intact, sectioned, and reconstructed knees at 30° and 90° of flexion for anterior-posterior laxity and external rotational laxity, as well as at 0° and 30° of flexion for varus laxity; dynamic 6 degrees of freedom kinematic testing, through a path of motion from 90° of flexion to full extension, was also performed. Results For the static varus tests, external rotation and varus laxity were significantly increased after the posterolateral structures were cut. Both reconstruction techniques restored external rotation and varus laxity to levels not significantly different from the intact state. For technique B, dynamic testing did not show any significant difference for all degrees of freedom kinematics compared with the intact state. However, for technique A, a significant internal tibial rotation was observed throughout the entire path of motion from 0° to 90° of knee flexion. Conclusions Both surgical techniques for anatomical posterolateral corner reconstruction showed good results in the static laxity tests. The anatomical reconstruction of all structures, including the popliteus tendon, resulted in an abnormal internal tibial rotation during dynamic testing.
An Assessment of the Methodological Quality of Research Published in the American Journal of Sports Medicine
Authors: Brophy Robert H. , Gardner Michael J. , Saleem Omar , Marx Robert G. 
Published: September 2005

Background Evidence-based medicine has become a popular topic in academic medicine during the past several decades and more recently in orthopaedics and sports medicine. Hypothesis Articles published in The American Journal of Sports Medicine have shown an improvement in methodological quality in 2001-2003, compared with 1991-1993. Study Design Systematic review. Methods All articles published in The American Journal of Sports Medicine during the periods 1991-1993 and 2001-2003 were reviewed and classified by type of study. The use of pertinent methodologies such as prospective data collection, randomization, blinding, and controlled studies was noted for each article. The frequency of each article type and the use of evidence-based techniques were compared across study periods. Results Case series and descriptive studies decreased during the study period, from 27.4% to 15.3% (P=. 00003) and from 11.9% to 5.6% (P=. 001), respectively, of articles published. Prospective cohort studies increased from 4.7% to 14.1% (P=. 000005), and randomized, prospective clinical trials increased from 2.7% to 5.9% of articles (P=. 04). More studies tested an explicit hypothesis (P=. 0000002), used prospective data collection (P=. 000003), and used blinding (P=. 02), and more studies identified a funding source (P=. 004). Conclusions Overall, there was a shift toward more prospective and randomized research designs published in The American Journal of Sports Medicine during 2001-2003 compared to 1991-1993, demonstrating an improvement in the methodological quality of published research.
The Effect of Relaxin Treatment on Skeletal Muscle Injuries
Authors: Negishi Shinichi , Li Yong , Usas Arvydas , Fu Freddie H. , Huard Johnny 
Published: September 2005

Background Injured skeletal muscle can repair itself via spontaneous regeneration; however, the overproduction of extracellular matrix and excessive collagen deposition lead to fibrosis. Neutralization of the effect of transforming growth factor-β1, a key fibrotic cytokine, on myogenic cell differentiation after muscle injury can prevent fibrosis, enhance muscle regeneration, and thereby improve the functional recovery of injured muscle. Hypothesis The hormone relaxin, a member of the family of insulin-like growth factors, can act as an antifibrosis agent and improve the healing of injured muscle. Study Design Controlled laboratory study. Methods In vitro: Myoblasts (C2C12 cells) and myofibroblasts (transforming growth factor-β1-transfected myoblasts) were incubated with relaxin, and cell growth and differentiation were examined. Myogenic and fibrotic protein expression was determined by Western blot analysis. In vivo: Relaxin was injected intramuscularly at different time points after laceration injury. Skeletal muscle healing was evaluated via histologic, immunohistochemical, and physiologic tests. Results Relaxin treatment resulted in a dose-dependent decrease in myofibroblast proliferation, down-regulated expression of the fibrotic protein α-smooth muscle actin, and promoted the proliferation and differentiation of myoblasts in vitro. Relaxin therapy enhanced muscle regeneration, reduced fibrosis, and improved injured muscle strength in vivo. Conclusion Administration of relaxin can significantly improve skeletal muscle healing. Clinical Relevance These findings may facilitate the development of techniques to eliminate fibrosis, enhance muscle regeneration, and improve functional recovery after muscle injuries.
Evaluation of Risk Factors for Injury in Adolescent Soccer
Authors: Emery Carolyn A. , Meeuwisse Willem H. , Hartmann Sara E. 
Published: September 2005

Background There are limited data on the epidemiology of adolescent soccer injury across all levels of play. Hypothesis Through implementation and validation of an injury surveillance system in adolescent soccer, risk factors for injury will be identified. Study Design Descriptive epidemiology study. Methods The study population was a random sample of 21 adolescent soccer teams (ages 12-18). A certified athletic therapist completed preseason baseline measurements and did weekly assessments of any identified soccer injury. The injury definition included any injury occurring in soccer that resulted in 1 or more of the following: medical attention, the inability to complete a session, or missing a subsequent session. Results Based on completeness of data in addition to validity of time loss, this method of surveillance has proven to be effective. The overall injury rate during the regular season was 5.59 injuries per 1000 player hours (95% confidence interval, 4.42-6.97). Soccer injury resulted in time loss from soccer for 86.9% of the injured players. Ankle and knee injuries were the most common injuries reported. Direct contact was reported to be involved in 46.2% of all injuries. There was an increased risk of injury associated with games versus practices (relative risk = 2.89; 95% confidence interval, 1.69-5.21). The risk of injury in the under 14 age group was greatest in the most elite division. Having had a previous injury in the past 1 year increased the risk of injury (relative risk = 1.74; 95% confidence interval, 1.0-3.1). Conclusion There were significant differences in injury rates found by division, previous injury, and session type (practice vs game). Future research should include the use of such a surveillance system to examine prevention strategies for injury in adolescent soccer.
Ulnar Wrist Pain in Athletes Caused by Erosion of the Floor of the Sixth Dorsal Compartment
Authors: Carneiro Ronaldo S. , Fontana Rosana , Mazzer Nilton 
Published: September 2005

Background Ulnar-side wrist pain can be disabling for athletes because of limitation of pronation-supination during sports such as tennis and golf. Erosion of the floor of the sixth dorsal space should be considered for unresponsive ulnar-side wrist pain. Study Design Case series; Level of evidence, 4. Methods Four athletes with severe unresponsive ulnar-side wrist pain were identified. Because the usual treatment regimens were ineffective in all cases, surgery was indicated to attempt mitigation of symptoms. During surgical exploration, all patients had inflammatory tendon changes and erosions in the floor of the sixth dorsal space, deep to the extensor carpi ulnaris. A soft tissue interposition flap fashioned from the roof of the sixth compartment was used to cover the defect. Results Patients were evaluated by reexamination for range of motion, ability to perform daily and sports activities, strength, and residual pain. All patients had relief of their symptoms, had normal range of motion with no residual pain, and returned to tennis and golf. Strength improved a mean of 15 lb after surgery. The follow-up was 19 to 40 months (mean, 33 months). Conclusion Erosion of the sixth compartment floor has been given very little attention in the literature. It should be suspected when severe ulnar-side pain persists in athletes after the usual methods of treatment. The interposition surgery described herein has been effective in 4 cases previously unresponsive to the usual methods of treatment for chronic tendinitis of the extensor carpi ulnaris or triangular fibrocartilage rupture.
D-glucuronyl C5-epimerase acts in dorso-ventral axis formation in zebrafish
Authors: Ghiselli Giancarlo , Farber Steven A 
Published: September 2005

Abstract

Background
Heparan sulfate (HS) is an ubiquitous component of the extracellular matrix that binds and modulates the activity of growth factors, cytokines and proteases. Animals with defective HS biosynthesis display major developmental abnormalities however the processes that are affected remain to be defined. D-glucuronyl-C5-epimerase (Glce) is a key HS chain modifying enzyme that catalyses the conversion of glucuronic acid into iduronic acid, a biosynthetic step that enhances HS biological activity. In this study the role of Glce during early zebrafish development has been investigated.

Results
Two Glce-like proteins (Glce-A and -B) are expressed in zebrafish at all times. They are the products of two distinct genes that, based on chromosomal mapping, are both orthologues of the same single human gene. Transcripts for both proteins were detected in fertilized zebrafish embryos prior to the onset of zygotic transcription indicating their maternal origin. At later developmental stages the epimerases are expressed widely throughout gastrulation and then become restricted to the hindbrain at 24 h post-fertilization. By monitoring the expression of well characterized marker genes during gastrulation, we have found that misexpression of Glce causes a dose-dependent expansion of the ventral structures, whereas protein knockdown using targeted antisense morpholino oligonucleotides promotes axis dorsalization. The ventralizing activity of Bmp2b is enhanced by Glce overexpression whereas Glce knockdown impairs Bmp2b activity.

Conclusion
Glce activity is an important determinant of of dorso-ventral axis formation and patterning in zebrafish. In particular Glce acts during gastrulation by affecting Bmp-mediated cell specification. The results obtained further corroborate the concept that HS encodes information that affect morphogenesis during early vertebrate development.
Functional genomics and expression analysis of the Corynebacterium glutamicum fpr2-cysIXHDNYZ gene cluster involved in assimilatory sulphate reduction
Authors: Rückert Christian , Koch Daniel J , Rey Daniel A , Albersmeier Andreas , Mormann Sascha , Pühler Alfred , Kalinowski Jörn 
Published: September 2005

Abstract

Background

Corynebacterium glutamicum is a high-GC Gram-positive soil bacterium of great biotechnological importance for the production of amino acids. To facilitate the rational design of sulphur amino acid-producing strains, the pathway for assimilatory sulphate reduction providing the necessary reduced sulfur moieties has to be known. Although this pathway has been well studied in Gram-negative bacteria like Escherichia coli and low-GC Gram-positives like Bacillus subtilis, little is known for the Actinomycetales and other high-GC Gram-positive bacteria.

Results
The genome sequence of C. glutamicum was searched for genes involved in the assimilatory reduction of inorganic sulphur compounds. A cluster of eight candidate genes could be identified by combining sequence similarity searches with a subsequent synteny analysis between C. glutamicum and the closely related C. efficiens. Using mutational analysis, seven of the eight candidate genes, namely cysZ, cysY, cysN, cysD, cysH, cysX, and cysI, were demonstrated to be involved in the reduction of inorganic sulphur compounds. For three of the up to now unknown genes possible functions could be proposed: CysZ is likely to be the sulphate permease, while CysX and CysY are possibly involved in electron transfer and cofactor biosynthesis, respectively. Finally, the candidate gene designated fpr2 influences sulphur utilisation only weakly and might be involved in electron transport for the reduction of sulphite. Real-time RT-PCR experiments revealed that cysIXHDNYZ form an operon and that transcription of the extended cluster fpr2 cysIXHDNYZ is strongly influenced by the availability of inorganic sulphur, as well as L-cysteine. Mapping of the fpr2 and cysIXHDNYZ promoters using RACE-PCR indicated that both promoters overlap with binding-sites of the transcriptional repressor McbR, suggesting an involvement of McbR in the observed regulation. Comparative genomics revealed that large parts of the extended cluster are conserved in 11 of 17 completely sequenced members of the Actinomycetales.

Conclusion
The set of C. glutamicum genes involved in assimilatory sulphate reduction was identified and four novel genes involved in this pathway were found. The high degree of conservation of this cluster among the Actinomycetales supports the hypothesis that a different metabolic pathway for the reduction of inorganic sulphur compounds than that known from the well-studied model organisms E. coli and B. subtilis is used by members of this order, providing the basis for further biochemical studies.
The neurotrophin receptor p75NTR mediates early anti-inflammatory effects of estrogen in the forebrain of young adult rats
Authors: Nordell Vanessa L , Lewis Danielle K , Bake Shameena , Sohrabji Farida 
Published: September 2005

AbstractBackgroundEstrogen suppresses microglial activation and extravasation of circulating monocytes in young animals, supporting an anti-inflammatory role for this hormone. However, the mechanisms underlying estrogen's anti-inflammatory effects, especiallyin vivo, are not well understood. The present study tests the hypothesis that anti-inflammatory effects of estrogen are mediated by the pan-neurotrophin receptor p75NTR. Previously, we reported that estrogen attenuated local increases of interleukin(IL)-1β in the NMDA-lesioned olfactory bulb, while further increasing NGF expression.ResultsThe present studies show that this lesion enhances expression of the neurotrophin receptor p75NTR at the lesion site, and p75NTR expression is further enhanced by estrogen treatment to lesioned animals. Specifically, estrogen stimulates p75NTR expression in cells of microvessels adjacent to the lesion site. To determine the role of this receptor in mediating estrogen's anti-inflammatory effects, a p75NTR neutralizing antibody was administered at the same time the lesion was created (by stereotaxic injections of NMDA) and specific markers of the inflammatory cascade were measured. Olfactory bulb injections of NMDA+vehicle (preimmune serum) increased IL-1β and activated the signaling molecule c-jun terminal kinase (JNK)-2 at 6 h. At 24 h, the lesion significantly increased matrix metalloproteinase (MMP)-9 and prostaglandin (PG)E2, a COX-2 mediated metabolite of arachadonic acid. All of these markers were significantly attenuated by estrogen in a time-dependent manner. However, estrogen's effects on all these markers were abolished in animals that received anti-p75NTR.ConclusionThese data support the hypothesis that estrogen's anti-inflammatory effects may be, in part, mediated by this neurotrophin receptor. In view of the novel estrogen-dependent expression of p75NTR in cells associated with microvessels, these data also suggest that the blood brain barrier is a critical locus of estrogen's neuro-immune effects.
Causal inference based on counterfactuals
Authors: Höfler M 
Published: September 2005

AbstractBackgroundThe counterfactual or potential outcome model has become increasingly standard for causal inference in epidemiological and medical studies.DiscussionThis paper provides an overview on the counterfactual and related approaches. A variety of conceptual as well as practical issues when estimating causal effects are reviewed. These include causal interactions, imperfect experiments, adjustment for confounding, time-varying exposures, competing risks and the probability of causation. It is argued that the counterfactual model of causal effects captures the main aspects of causality in health sciences and relates to many statistical procedures.SummaryCounterfactuals are the basis of causal inference in medicine and epidemiology. Nevertheless, the estimation of counterfactual differences pose several difficulties, primarily in observational studies. These problems, however, reflect fundamental barriers only when learning from observations, and this does not invalidate the counterfactual concept.
Anthracyclines, proteasome activity and multi-drug-resistance
Authors: Fekete Mirela R , McBride William H , Pajonk Frank 
Published: September 2005

AbstractBackgroundP-glycoprotein is responsible for the ATP-dependent export of certain structurally unrelated compounds including many chemotherapeutic drugs. Amplification of P-glycoprotein activity can result in multi-drug resistance and is a common cause of chemotherapy treatment failure. Therefore, there is an ongoing search for inhibitors of P-glycoprotein. Observations that cyclosporin A, and certain other substances, inhibit both the proteasome and P-glycoprotein led us to investigate whether anthracyclines, well known substrates of P-gp, also inhibit the function of the proteasome.MethodsProteasome function was measured in cell lysates from ECV304 cells incubated with different doses of verapamil, doxorubicin, daunorubicin, idarubicin, epirubicin, topotecan, mitomycin C, and gemcitabine using a fluorogenic peptide assay. Proteasome function in living cells was monitored using ECV304 cells stably transfected with the gene for an ubiquitin/green fluorescent protein fusion protein. The ability of the proteasome inhibitor MG-132 to affect P-glycoprotein function was monitored by fluorescence due to accumulation of daunorubicin in P-glycoprotein overexpressing KB 8-5 cells.ResultsVerapamil, daunorubicin, doxorubicin, idarubicin, and epirubicin inhibited 26S chymotrypsin-like function in ECV304 extracts in a dose-dependent fashion. With the exception of daunorubicin, 20S proteasome function was also suppressed. The proteasome inhibitor MG-132 caused a dose-dependent accumulation of daunorubicin in KB 8-5 cells that overexpress P-glycoprotein, suggesting that it blocked P-glycoprotein function.ConclusionOur data indicate that anthracyclines inhibit the 26S proteasome as well as P-glycoprotein. Use of inhibitors of either pathway in cancer therapy should take this into consideration and perhaps use it to advantage, for example during chemosensitization by proteasome inhibitors.
The impact of prior outpatient ACE inhibitor use on 30-day mortality for patients hospitalized with community-acquired pneumonia
Authors: Mortensen Eric M , Restrepo Marcos I , Anzueto Antonio , Pugh Jacqueline 
Published: September 2005

Abstract

Background
Recent studies suggest that angiotensin-converting enzyme (ACE) inhibitors may have beneficial effects for patients at risk for some types of infections. We examined the effect of prior outpatient use of ACE inhibitors on mortality for patients hospitalized with community-acquired pneumonia.

Methods
A retrospective cohort study conducted at two tertiary teaching hospitals. Eligible subjects were admitted with a diagnosis of, had a chest x-ray consistent with, and had a discharge ICD-9 diagnosis of pneumonia. Subjects were excluded if they were "comfort measures only" or transferred from another acute care hospital. Subjects were considered to be on a medication if they were taking it at the time of presentation.

Results
Data was abstracted on 787 subjects at the two hospitals. Mortality was 9.2% at 30-days and 13.6% at 90-days. At presentation 52% of subjects were low risk, 34% were moderate risk, and 14% were high risk. In the multivariable conditional logistic regression analysis, after adjusting for potential confounders, the use of ACE inhibitors at presentation (odds ratio 0.44, 95% confidence interval 0.22–0.89) was significantly associated with 30-day mortality.

Conclusion
Prior outpatient use of an ACE inhibitor was associated with decreased mortality in patients hospitalized with community-acquired pneumonia despite their use being associated with comorbid illnesses likely to contribute to increased mortality. Confirmatory studies are needed, as well as research to determine the mechanism(s) of this protective effect.
Aggregation as bacterial inclusion bodies does not imply inactivation of enzymes and fluorescent proteins
Authors: García-Fruitós Elena , González-Montalbán Nuria , Morell Montse , Vera Andrea , Ferraz Rosa María , Arís Anna , Ventura Salvador , Villaverde Antonio 
Published: September 2005

Abstract

Background
Many enzymes of industrial interest are not in the market since they are bio-produced as bacterial inclusion bodies, believed to be biologically inert aggregates of insoluble protein.

Results
By using two structurally and functionally different model enzymes and two fluorescent proteins we show that physiological aggregation in bacteria might only result in a moderate loss of biological activity and that inclusion bodies can be used in reaction mixtures for efficient catalysis.

Conclusion
This observation offers promising possibilities for the exploration of inclusion bodies as catalysts for industrial purposes, without any previous protein-refolding step.