bluuebunny/crossref_metadata_2025_split huggingface dataset:
A market without the ‘right’ property rights
Authors: Kim Annette M. 
Published: May 2004

AbstractWhile Vietnam's reforms provided some of the weakest legal private property rights amongst the transitions countries, cities like Ho Chi Minh City have booming domestic real estate markets. Interestingly, while most properties in 2001 did not have legal title, those on the market did advertise a variety of property rights claims. Employing a hedonic price model to analyse the pattern of prices at which sellers offer properties in Ho Chi Minh City, this study examines how this market values property rights. The findings show that multiple forms of property rights, enforced by highly decentralized state institutions, are operational in this market. Furthermore, legal title itself is not the most valuable form of property right. These findings suggest that the value of property rights emanates from where it is enforced within the particular institutional context of a market.
Prognosis of large cyst‐like periapical lesions following nonsurgical root canal treatment: a clinical review
Authors: Çalışkan M. K. 
Published: May 2004

AbstractAim  To evaluate clinically and radiographically the long‐term clinical outcome of nonsurgical root canal treatment using calcium hydroxide in teeth with large cyst‐like periapical lesions.Summary  A total of 42 mature anterior teeth with large periapical lesions ranging in size from 7 to 18 mm in diameter were included in this study. Fluid samples from the lesions contained cholesterol crystals, which were identified by light microscopy. After adequate draining, the teeth were treated endodontically using calcium hydroxide as the intracanal medicament. All cases were followed up for a period of 2–10 years. Complete healing was observed in 73.8% and incomplete healing in a further 9.5% of cases.Key learning points• Root canal treatment using calcium hydroxide as an antibacterial dressing was successful in healing large cyst‐like periapical lesions.• This study suggests that the size of a periapical lesion is not a major determining factor in the decision to perform conventional root canal treatment or surgical removal of the lesion. Even large cyst‐like periapical lesions containing cholesterol crystals can heal following nonsurgical root canal treatment.
An evaluation of the use of tooth temperature to assess human pulp vitality
Authors: Smith E. , Dickson M. , Evans A. L. , Smith D. , Murray C. A. 
Published: May 2004

AbstractAim  To evaluate change in tooth surface temperature following a thermal stimulus as a simple and reliable method to assess the presence and the extent of blood flow through teeth.Methodology  Miniature thermometers were used to measure the relationship between surface temperature of teeth and internal flow of 37 °C water (in vitro) or blood (in vivo). In addition, thermal stimuli were applied to the external surface of the teeth, and the rate of temperature recovery was related to internal flow.Results  Under in vitro conditions, the surface temperature of teeth and rate of temperature recovery were related to the rate of internal water flow. However, in vivo neither standing surface temperature (P = 0.47) nor rate of temperature recovery (P = 0.19) were significantly related to evidential pulp vitality.Conclusion  Change in the surface temperature of teeth is not suitable as a simple clinical means to assess pulp vitality.
Prevalence of and factors affecting post‐obturation pain in patients undergoing root canal treatment
Authors: Ng Y.‐L. , Glennon J. P. , Setchell D. J. , Gulabivala K. 
Published: May 2004

AbstractAim  This longitudinal, prospective study (1) investigated the prevalence of post‐obturation pain after root canal treatment and (2) evaluated the influence of factors affecting the pain experience.Methodology  Twenty practitioners, comprising general dental practitioners, MSc graduates and Endodontists, participated in this study. The patient sample (n = 415) was derived from consecutive patients attending the practitioners’ surgeries for root canal treatment on a single tooth. Demographic, medical history, preoperative and intra‐operative data as well as pain experience on day 1 and day 2 after root canal obturation were recorded. Intensity of pain experienced was recorded on a visual analogue scale (VAS) of 0–5. The data were analysed using logistic regression models.Results  The prevalence of post‐obturation pain within 48 h after treatment was 40.2% (n = 167) but less than 12% of patients experienced severe pain (VAS 4 or 5) on either day 1 or day 2. The factors that significantly influenced post‐obturation pain experience were: gender (OR = 0.434, P < 0.001), tooth type (OR = 1.733, P = 0.007), size of periapical lesion (OR = 0.493, P = 0.004), history of post‐preparation pain (OR = 4.110, P = <0.001) or generalized swelling (OR = 3.435, P = 0.005) and number of treatment visits (OR = 2.604, P < 0.001).Conclusions  The prevalence of post‐obturation pain was high (40.2%). The important prognostic determinants of post‐obturation pain were female, molar tooth, size of periapical lesion smaller than 3 mm, history of post‐preparation pain or generalized swelling and single‐visit treatment.
The Synechococcus elongatus PII signal transduction protein controls arginine synthesis by complex formation with N‐acetyl‐l‐glutamate kinase
Authors: Heinrich Annette , Maheswaran Mani , Ruppert Ulrike , Forchhammer Karl 
Published: May 2004

SummaryThis communication identifies, for the first time, a receptor protein for signal perception from the PII signal transduction protein in the cyanobacterium Synechococcus elongatus. PII, a phosphoprotein that signals the carbon/nitrogen status of the cells, forms a tight complex with the key enzyme of the arginine biosynthetic pathway, N‐acetylglutamate (NAG) kinase. In complex with PII, the catalytic activity of NAG kinase is strongly enhanced. Complex formation does not require the effector molecules of PII, 2‐oxoglutarate and ATP, but it is highly susceptible to modifications at the phosphorylation site of PII, Ser‐49. Stable complexes were only formed with the non‐phosphorylated form of PII but not with Ser‐49 mutants. In accordance with these data, NAG kinase activity in S. elongatus extracts correlated with the phosphorylation state of PII, with high NAG kinase activities corresponding to non‐phosphorylated PII (nitrogen‐excess conditions) and low activities to increased levels of PII phosphorylation (nitrogen‐poor conditions), thus subjecting the key enzyme of arginine biosynthesis to global nitrogen control.
Structure, function and evolution of microbial adenylyl and guanylyl cyclases
Authors: Baker David A. , Kelly John M. 
Published: May 2004

SummaryCells respond to signals of both environmental and biological origin. Responses are often receptor mediated and result in the synthesis of so‐called second messengers that then provide a link between extracellular signals and downstream events, including changes in gene expression. Cyclic nucleotides (cAMP and cGMP) are among the most widely studied of this class of molecule. Research on their function and mode of action has been a paradigm for signal transduction systems and has shaped our understanding of this important area of biology. Cyclic nucleotides have diverse regulatory roles in both unicellular and multicellular organisms, highlighting the utility and success of this system of molecular communication. This review will examine the structural diversity of microbial adenylyl and guanylyl cyclases, the enzymes that synthesize cAMP and cGMP respectively. We will address the relationship of structure to biological function and speculate on the complex origin of these crucial regulatory molecules. A review is timely because the explosion of data from the various genome projects is providing new and exciting insights into protein function and evolution.
Knee Laxity Does Not Vary with the Menstrual Cycle, before or after Exercise
Authors: Belanger Michael J. , Moore Douglas C. , Crisco Joseph J. , Fadale Paul D. , Hulstyn Michael J. , Ehrlich Michael G. 
Published: May 2004

Background An intriguing explanation for the disproportionately high rate of anterior cruciate ligament injury in female athletes is that the structural properties of the anterior cruciate ligament are affected by the menstrual hormones. Whether this actually occurs, however, is the subject of ongoing debate. Hypotheses (1) Anterior cruciate ligament laxity is different in the follicular, ovulatory, and luteal phases of the menstrual cycle, and (2) exercise exacerbates the difference in anterior cruciate ligament laxity in the 3 phases. Methods Over the course of 10 weeks, repeated knee laxity measurements were taken on 27 high-level female athletes, before and after exercise. Point in the menstrual cycle was determined with charts of waking temperature and menstruation. The independent effects of menstrual phase and exercise were evaluated using generalized estimating equations. Results Data from 18 participants were included in the final analysis. There were no significant differences in anterior cruciate ligament laxity in any of the 3 menstrual phases, before or after exercise. Conclusions Anterior cruciate ligament laxity is not significantly different during the follicular, ovulatory, and luteal phases of the menstrual cycle, and bicycling exercise does not exacerbate or create any differences in anterior cruciate ligament laxity.
Ulnar Collateral Ligament Reconstruction in High School Baseball Players
Authors: Petty Damon H. , Andrews James R. , Fleisig Glenn S. , Cain E. Lyle 
Published: May 2004

Background The incidence of ulnar collateral ligament injury has increased in baseball, especially at the high school level. Hypothesis Ulnar collateral ligament injury in high school baseball players is associated with overuse, high-velocity throwing, early throwing of breaking pitches, and improper warm-ups. Study Design Retrospective cohort study. Methods Follow-up physical examination and questionnaire data were collected at an average of 35 months after ulnar collateral ligament reconstruction from 27 former high school baseball players. Six potential risk factors were evaluated: year-round throwing, seasonal overuse, event overuse, throwing velocity more than 80 mph, throwing breaking pitches before age 14, and inadequate warm-ups. Results Overall, 74% returned to baseball at the same or higher level. Patients averaged 3 potential risk factors, and 85% demonstrated at least one overuse category. Of the pitchers, the average self-reported fastball velocity was 83 mph, and 67% threw breaking pitches before age 14. Conclusions The success rate of ulnar collateral ligament reconstruction in high school baseball players is nearly equal to that in more mature groups of throwers. Overuse of the throwing arm and throwing breaking pitches at an early age may be related to their injuries. Special attention should be paid to elite-level teenage pitchers who throw with high velocity.
Reducing the Lateral Force Acting on the Patella Does Not Consistently Decrease Patellofemoral Pressures
Authors: Elias John J. , Cech Jennifer A. , Weinstein David M. , Cosgrea Andrew J. 
Published: May 2004

Background Extensor mechanism procedures that decrease the lateral component of the patellar tendon or quadriceps force acting on the patella do not consistently reduce pain. Hypothesis Patellofemoral treatments do not consistently decrease patellofemoral pressures because of variations in the moments acting on the patella. Study Design Computer simulation study. Methods Computational models of 4 knees were constructed to characterize the patellofemoral pressure distribution during simulated squatting from 40° to 90°. The knees were given an initial Q angle of 25°. Patellofemoral treatments were simulated by increasing the percentage of the quadriceps force applied by the vastus medialis by 50% and by medializing the tibial tuberosity to decrease the Q angle to 15°. Results Decreasing the Q angle caused a larger decrease in the lateral component of the force applied by the quadriceps and patellar tendon than did increasing the force applied by the vastus medialis and, therefore, was more effective at decreasing patellofemoral pressures and the force needed to resist lateral subluxation. Both treatments also decreased the moments acting to rotate the distal patella laterally and tilt the patella laterally during flexion. Variations in these moments increased patellofemoral pressures for some knees. Conclusions Treatments that reduce patellofemoral subluxation can have an unexpected influence on patellofemoral pressures because of the moments acting on the patella. Clinical Relevance Extensor mechanism procedures that restore patellofemoral stability may not provide pain relief.
Sagittal Plane Translation during Level Walking in Poor-Functioning and Well-Functioning Patients with Anterior Cruciate Ligament Deficiency
Authors: Kvist Joanna 
Published: May 2004

Background Some patients with anterior cruciate ligament deficiency can function well and participate in high-level sports, whereas others have functional limitations even during activities of daily living. Hypothesis Patients who function well after an anterior cruciate ligament injury can stabilize the knee joint during gait by an anterior positioning of the tibia. Study Design Controlled laboratory study. Methods Sagittal tibial translation was registered with the CA-4000 electrogoniometer, during the Lachman test and walking, in 20 patients with a unilateral anterior cruciate ligament injury. Eleven patients functioned well (Lysholm score [.greaterequal]84), and 9 patients had poor knee function (Lysholm score <84). Results During gait, the well-functioning group had 24% greater anterior translation in the injured leg compared to the noninjured leg. In the poor-functioning group, the anterior translation in the injured leg was 16% smaller compared to the noninjured leg (P = .0003). Tibial translation during the Lachman test was similar in the injured leg in the 2 groups. Conclusion Patients who function well position their tibiae near the anterior border of the joint play. This position may encourage functional stability. Clinical Relevance Rehabilitation that emphasizes training to stabilize the tibia in an anterior position may improve functional stability of the anterior cruciate ligament-deficient knee.
Matrix Metalloproteinase and Tissue Inhibitor of Matrix Metalloproteinase mRNA Levels are Specifically Altered in Torn Rotator Cuff Tendons
Authors: Lo Ian K. Y. , Marchuk Linda L. , Hollinshead Robert , Hart David A. , Frank Cyril B. 
Published: May 2004

Background Rotator cuff tears are a cause of pain and disability in the shoulder. The molecular changes associated with rotator cuff tearing are unclear. A subset of matrix metalloproteinases and tissue inhibitors of metalloproteinase, which are involved in extracellular matrix remodeling and degradation, were evaluated. Hypothesis There would be an increase in the mRNA level of spcific matrix metalloproteinase and a decrease in the mRNA level of specific tissue inhibitors of metalloproteinase in rotator cuff tendon tissue obtained from patients with rotator cuff tears. Study Design Controlled laboratory study. Methods Tissue was obtained from 10 patients undergoing rotator cuff repair for full-thickness rotator cuff tears. Also, tissue was obtained from cadaveric specimens with no gross evidence of rotator cuff tearing. Reverse transcription polymerase chain reaction was performed for the collagenases (MMP-1, MMP-8, MMP-13), the stromelysins (MMP-3, MMP-10, MMP-11), and the tissue inhibitors of metalloproteinase (TIMP-1, TIMP-2, TIMP-3, TIMP-4). Western blotting was performed to confirm the mRNA changes demonstrated in collagenase-3 (MMP-13). Results There was a significant increase in collagenase-3 (MMP-13) mRNA levels, a decrease in stromelysin-1 (MMP-3) mRNA levels, and a decrease in tisue inhibitor of metalloproteinase-2, -3, and -4 mRNA levels. Western blotting demonstrated an increase in the active form of collagenase-3 (MMP-13) in rotator cuff tendon tears. Conclusions The mRNA levels of specific matrix metalloproteinases and tissue inhibitors of metalloproteinase are altered in torn rotator cuff tendons. Clinical Relevance With the known action of the matrix metalloproteinases and tissue inhibitors of metalloproteinase in extra-cellular matrix remodeling, these findings suggest that their roles in remodeling of rotator cuff tears should be further investigated.
Glenohumeral Arthrosis in Anterior Instability before and after Surgical Treatment
Authors: Buscayret Florent , Edwards Thomas Bradley , Szabo Istvan , Adeleine Patrice , Coudane Henri , Walch Gilles 
Published: May 2004

Background Few large series of arthropathy related to anterior glenohumeral instability are available in the orthopaedic literature, preventing analysis of the incidence and the risk factors of preoperative and postoperative glenohumeral arthritis. Hypothesis Anterior stabilization surgery influences the risk factors of glenohumeral arthritis. Study Design Retrospective review. Methods There were 570 patients who underwent an instability procedure. Clinical and radiographic preoperative data were collected for these patients. Arthritis was evaluated preoperatively and postoperatively with the Samilson classification. The mean age at surgery was 31.9 years. Follow-up averaged 6.5 years. Results The preoperative incidence of arthritis was 9.2%. Arthritic risk factors were older age at the initial dislocation and at surgery, increased length of time from the initial dislocation until surgery, and the presence of osseous glenoid rim lesions. Postoperative arthritis in patients without any preoperative arthritis occurred in 19.7% and was correlated with older age at the initial dislocation and at surgery, increased number of dislocations, and longer follow-up. Decreased external rotation at latest follow-up correlated with arthritis, although whether this was the cause or the effect was unclear. Conclusions Similar factors contribute to preoperative and postoperative arthritis in patients with anterior glenohumeral instability, suggesting that surgery does not influence the risk factors of arthritis. Although decreased external rotation with the arm at side statistically correlated with arthritis in this study, the authors were unable to establish this as an effectual relationship because nearly all patients with glenohumeral osteoarthritis, whether instability related or not, have decreased external rotation.
Eccentric Training of the Gastrocnemius-Soleus Complex in Chronic Achilles Tendinopathy Results in Decreased Tendon Volume and Intratendinous Signal as Evaluated by MRI
Authors: Shalabi Adel , Kristoffersen-Wilberg Maria , Svensson Leif , Aspelin Peter , Movin Tomas 
Published: May 2004

Background Satisfactory treatment results have been reported after eccentric calf muscle strength training in patients with chronic Achilles tendinopathy. Hypothesis Magnetic resonance imaging may be a useful adjunct in the evaluation of the effect of 3 months of eccentric calf muscle strength training. Study Design Prospective cohort study. Methods Using magnetic resonance imaging, the Achilles tendons were investigated in 25 patients (16 men and 9 women) ranging in age from 28 to 70 years (median, 51 years) before and after training. Five different magnetic resonance imaging sequences were used. Tendon volume and mean intratendinous signal were calculated using a new seed-growing technique showing 99.3% and 96.6% intraobserver reliability, respectively. The clinical outcome was categorized according to pain level and performance using a questionnaire completed by the patient. Results The eccentric training resulted in a 14% (mean) decrease of tendon volume measured on T1-weighted images, from 6.6 ± 3.1 cm3 to 5.8 ± 2.3 cm3 (P < .05). The intratendinous signal in the symptomatic Achilles tendon measured on proton density-weighted images decreased 23% (mean), from 227 ± 77 signal units to 170 ± 83 signal units (P < .05). The gadolinium contrast agent-enhanced images did not add further value compared with other sequences. Clinical Outcome The clinical outcome was categorized as excellent in 10, good in 3, fair in 5, and poor in 8 patients. The [. Delta]signal correlated significantly with the pain level (P < .05). Conclusions Eccentric training resulted in decreased tendon volume and intratendinous signal and was correlated with an improved clinical outcome. Magnetic resonance imaging techniques can be used as an adjunct to clinical evaluation by monitoring morphologic effects in clinical treatment studies of Achilles tendinopathy.
A dose effect of IL-7 on thymocyte development
Authors: El Kassar Nahed , Lucas Philip J. , Klug David B. , Zamisch Monica , Merchant Melinda , Bare Catherine V. , Choudhury Baishakhi , Sharrow Susan O. , Richie Ellen , Mackall Crystal L. , Gress Ronald E. 
Published: May 2004

AbstractTo study interleukin-7 (IL-7) in early thymocyte development, we generated mice transgenic (Tg) for the IL-7 gene under control of the lck proximal promoter. Founder line TgA, with the lowest level of IL-7 overexpression, showed enhanced αβ T-cell development. In contrast, in the highest overexpressing founder line, TgB, αβ T-cell development was disturbed with a block at the earliest intrathymic precursor stage. This was due to decreased progenitor proliferation as assessed by Ki-67 staining and in vivo bromodeoxyuridine (BrdU) incorporation. Bcl-2 was up-regulated in T-cell–committed progenitors in all Tg lines, and accounted for greater numbers of double positive (DP), CD4 single positive (SP), and CD8SP thymocytes in TgA mice where, in contrast to TgB mice, thymocyte progenitor proliferation was normal. Mixed marrow chimeras using TgB+ and congenic mice as donors, and experiments using anti–IL-7 monoclonal antibody (MAb) in vivo, confirmed the role of IL-7 protein in the observed TgB phenotype. In conclusion, at low Tg overexpression, IL-7 enhanced αβ T-cell development by increasing thymocyte progenitor survival, while at high overexpression IL-7 reduces their proliferation, inducing a dramatic block in DP production. These results show for the first time in vivo a dose effect of IL-7 on αβ T-cell development and have implications for IL-7 in the clinical setting.