bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of the Incidence of Periodontitis‐Associated Bacteria in the Atherosclerotic Plaque of Coronary Blood Vessels
Authors: Zaremba Maciej , Górska Renata , Suwalski Piotr , Kowalski Jan 
Published: February 2007

Background: Unstable atherosclerotic plaque is a dangerous clinical condition, possibly leading to acute coronary deficiency resulting in cardiac infarction. Questions about the role of inflammatory factors in the formation of pathological lesions in the endothelium of coronary vessels have often been raised. This condition may be caused by bacteria that are able to initiate clot formation in a blood vessel, destabilizing an atherosclerotic plaque that is already present. The sources of these pathogens are chronic inflammatory processes occurring in the host, including periodontal disease, which is one of the most frequent conditions. The aim of this study was to evaluate the incidence of selected anaerobic bacteria in subgingival and atherosclerotic plaque in patients treated surgically because of coronary vessel obliteration.Methods: The study was performed on 20 individuals with chronic periodontitis. Subgingival plaque was collected from periodontal pockets >5 mm. DNA testing was used to identify eight pathogens responsible for periodontal tissue destruction. Material from atherosclerotic plaques was collected from the same patients during bypass surgery, and DNA testing by the same method was performed.Results: In 13 of 20 patients, the pathogens most frequently found in severe chronic periodontitis were also found in coronary vessels. In 10 cases, those species of bacteria were also present in atherosclerotic plaque. The most frequently identified bacteria were Porphyromonas gingivalis and Treponema denticola.Conclusions: In patients with the severe form of chronic periodontitis, it seems that clinical attachment loss is not associated with bacterial permeability into coronary vessels. What is important is the presence of an active inflammatory process expressed by a significantly higher bleeding index in those patients in whom the examined bacterial species were found in atherosclerotic plaque.
Tissue Engineering Bone Formation in Novel Recombinant Human Bone Morphogenic Protein 2–Atelocollagen Composite Scaffolds
Authors: Hou Lein‐Tuan , Liu Cheng‐Meei , Liu Bu‐Yuan , Chang Po‐Chun , Chen Min‐Huei , Ho Ming‐Hua , Jehng Su‐Min , Liu Hwa‐Chang 
Published: February 2007

Background: Bone morphogenic proteins (BMPs) are important bone‐induction factors, and the development of a suitable carrier for BMPs is a critical step to achieve osteoinductive function. The aims of the present study were to evaluate, at the cellular and molecular levels, the feasibility of recombinant human BMP‐2 (rhBMP‐2)–collagen composite scaffold and its efficiency for carrying BMP‐2 in ectopic bone formation in rats.Methods: Scaffolds with (test) or without rhBMP‐2 (control) were made and implanted into the calf muscle of 16 5‐week‐old rats. The tissue responses to the scaffolds were examined by histology. Masson's trichrome and von Kossa stainings were performed to examine collagen matrix deposition and calcification at 3, 7, 10, and 14 days. Expressions of bone phenotypic markers, alkaline phosphatase, osteocalcin, osteopontin, and bone sialoprotein were detected by reverse transcription‐polymerase chain reaction and immunohistochemistry.Results: No detectable adverse responses were noted around the implanted scaffolds, and the area of the resorbed scaffold had been replaced by young connective tissue by 3 to 7 days in both groups. In the rhBMP‐2 composite scaffold, collagen matrix deposition was found in the implanted site on day 7 and initial signs of endochondral differentiation also appeared. Mineralization and the expressions of key bone proteins were demonstrated in chondroblasts and osteoblasts at 7 to 14 days. Molecular cascades of bone induction were not shown in control specimens.Conclusion: The rhBMP‐2–atelocollagen scaffold showed excellent biocompatibility and possessed a bone‐inducing capacity in rat within 2 weeks, and, thus, may provide a potential application in tissue engineering of bone tissue.
Peri‐Implant Bone Loss Around Posterior Mandible Dental Implants Placed After Distraction Osteogenesis: Preliminary Findings
Authors: Polo Wilson C.K. , de Araujo Ney Soares , Lima Ynara B.O. , Joly Julio Cesar , Sendyk Wilson R. , Cury Patricia R. 
Published: February 2007

Background: The present study evaluates implant survival and peri‐implant bone loss around posterior mandible dental implants placed at sites of distraction osteogenesis.Methods: On removal of the distraction devices, 34 dental implants were inserted into 14 posterior mandible sites in 10 healthy, non‐smoking female patients. Prosthetic treatment was performed 4 months after implant placement using fixed implant prostheses. After 6 to 16.5 months, periapical radiographs were taken and evaluated for peri‐implant bone loss and radiolucency. The distance between the implant margin and the first visible bone–implant contact was measured on the mesial and distal aspects of the implants using imaging software. Radiographic dimensional distortion was corrected as a function of the known true dimension of the implant.Results: Of the 34 implants placed, two (5.9%) failed to integrate at reentry surgery. Both were replaced and restored during the course of the study so that a total of 34 implants was followed for 12.1 ± 3.8 months post‐restoration and 16.1 ± 3.8 months post‐insertion. Mean loss of marginal bone height was 2.6 ± 1.0 mm. During the follow‐up period, radiolucent lines along the implant surface were absent.Conclusions: The mean peri‐implant bone loss in areas of alveolar bone distraction was 1.9 mm/year. A high implant survival rate was observed.
Alveolar Distraction Osteogenesis for Bone Augmentation of Severely Atrophic Ridges in 10 Consecutive Cases: A Histologic and Histomorphometric Study
Authors: Marchetti Claudio , Corinaldesi Giuseppe , Pieri Francesco , Degidi Marco , Piattelli Adriano 
Published: February 2007

Background: This study analyzed bone healing in surgically osteodistracted maxillary and mandibular ridges histologically and histomorphometrically at two different times to determine the best time to insert dental implants.Methods: Ten consecutive patients with severe maxillary (two patients) or mandibular (eight patients) atrophy underwent surgical osteodistraction with an extraosseous distractor. Seven days after the surgery, the distractor was activated at a rate of 1 mm/day until achieving the planned bone lengthening. The distractor was removed after a consolidation period of 70 days. Bone biopsies were obtained at implant insertion: 70 days after the end of distraction on the day of distractor removal in six patients (group A) or 180 days afterwards in four patients (group B). The biopsies were evaluated histologically and histomorphometrically to measure the osteocyte lacunar area (OLA).Results: The histologic and histomorphometrical analysis of the distracted bone 70 days after the end of distraction showed well‐organized lamellar bone. At 180 days, the bone was more compact and mature; the mineralization of the matrix was greater; and an increased, but small, amount of marrow space was evident (35% versus 45%). The mean OLA was 80.11 ± 27.59 μm2 in group A and 70.4 ± 33.58 μm2 in group B. The difference between the two biopsy groups was not significant (P = 0.315).Conclusion: The results of this study showed that there was definitely similar bone formation in the distracted area for both healing periods, and placing implants clinically worked in both of these time periods in the limited number of cases observed.
Survival of Immediately Provisionalized Dental Implants Placed Immediately Into Fresh Extraction Sockets
Authors: Schwartz‐Arad Devorah , Laviv Amir , Levin Liran 
Published: February 2007

Background: The aim of this study was to evaluate the survival rate of immediately provisionalized dental implants immediately placed into fresh extraction sockets.Methods: The study consisted of 87 consecutive patients, ranging in age from 21 to 76 years (average: 53.30 ± 13.34 years), who received 210 immediately provisionalized, immediately placed dental implants between the years 2000 and 2005. Data were recorded regarding the survival rate of these implants and the incidence of complications.Results: Follow‐up ranged from 6 to 52 months (mean: 15.60 ± 12.60 months). Smoking, past and present, was reported by 28.7% and 20.7% of patients, respectively. The maxillary incisors were replaced most frequently, followed by the mandibular lateral incisors. Most of the implants were >13 mm in length and ≥3.75 mm in diameter. There were 47 (22.4%) single restored implants and 163 (77.6%) splinted implants. Overall, the implant survival rate was 97.6% (five implants failed). Complications, such as swelling, inflammation, and pain, were observed in 24 (11.4%) of the implants. No relation was found between complications and failure. The present study failed to reveal a relationship between implant survival rate and smoking, implant dimensions, and area of implantation.Conclusion: Immediately provisionalized immediate implants can serve as a predictable procedure with high survival rates.
Lung Cancer Risk and Workplace Exposure to Environmental Tobacco Smoke
Authors: Stayner Leslie , Bena James , Sasco Annie J. , Smith Randall , Steenland Kyle , Kreuzer Michaela , Straif Kurt 
Published: February 2007

Objectives. We sought to quantitatively evaluate the association between work-place environmental tobacco smoke exposure and lung cancer. Methods. We performed a meta-analysis in 2003 of data from 22 studies from multiple locations worldwide of workplace environmental tobacco smoke exposure and lung cancer risk. Estimates of relative risk from these studies were analyzed by fitting the data to fixed and mixed effects models. Analyses of highly exposed workers and of the relationship between duration of exposure and lung cancer were also performed. Results. The meta-analysis indicated a 24% increase in lung cancer risk (relative risk [RR]=1.24; 95% confidence interval [CI]=1.18, 1.29) among workers exposed to environmental tobacco smoke. A 2-fold increased risk (RR=2.01; 95% CI=1.33, 2.60) was observed for workers classified as being highly exposed to environmental tobacco smoke. A strong relationship was observed between lung cancer and duration of exposure to environmental tobacco smoke. Conclusions. The findings from this investigation provide the strongest evidence to date that exposure to environmental tobacco smoke in the workplace is associated with an increased risk of lung cancer.
Social and Political Factors Predicting the Presence of Syringe Exchange Programs in 96 US Metropolitan Areas
Authors: Tempalski Barbara , Flom Peter L. , Friedman Samuel R. , Des Jarlais Don C. , Friedman Judith J. , McKnight Courtney , Friedman Risa 
Published: February 2007

Community activism can be important in shaping public health policies. For example, political pressure and direct action from grassroots activists have been central to the formation of syringe exchange programs (SEPs) in the United States. We explored why SEPs are present in some localities but not others, hypothesizing that programs are unevenly distributed across geographic areas as a result of political, socioeconomic, and organizational characteristics of localities, including needs, resources, and local opposition. We examined the effects of these factors on whether SEPs were present in different US metropolitan statistical areas in 2000. Predictors of the presence of an SEP included percentage of the population with a college education, the existence of local AIDS Coalition to Unleash Power (ACT UP) chapters, and the percentage of men who have sex with men in the population. Need was not a predictor.
Achieving Energy Balance at the Population Level Through Increases in Physical Activity
Authors: Costanza Michael C. , Beer-Borst Sigrid , Morabia Alfredo 
Published: February 2007

Objectives. We estimated the amount of physical activity required for individuals to expend an additional 418.4 kJ (100 kcal) per day with the goal of achieving energy balance at the population level. Methods. Data on total daily energy expenditures were derived from a random sample of adults residing in Geneva, Switzerland, who completed a self-administered physical activity frequency questionnaire. These data were used to simulate the effects of typical physical activity pyramid recommendations on average population energy expenditures for various activity intensities and rates of population compliance with pyramid recommendations. Results. If an average 418.4 kJ (100 kcal) per day increase in energy expenditures is to be achieved, assuming 100% compliance with physical activity pyramid recommendations, the bottom tier of the pyramid must correspond to everyday activities performed at moderate to high intensity levels (e.g., moderate walking or biking). Expected population gains in energy expenditures would be only 167.4 to 251.0 kJ (40 to 60 kcal) per day at a 50% compliance rate. Conclusions. Achieving population-level energy balance through increasing energy expenditures with physical activity increases alone would require profound structural and environmental changes promoting more active lifestyles.
Contribution of Public Parks to Physical Activity
Authors: Cohen Deborah A. , McKenzie Thomas L. , Sehgal Amber , Williamson Stephanie , Golinelli Daniela , Lurie Nicole 
Published: February 2007

Objectives. Parks provide places for people to experience nature, engage in physical activity, and relax. We studied how residents in low-income, minority communities use public, urban neighborhood parks and how parks contribute to physical activity. Methods. In 8 public parks, we used direct observation to document the number, gender, race/ethnicity, age group, and activity level of park users 4 times per day, 7 days per week. We also interviewed 713 park users and 605 area residents living within 2 miles of each park. Results. On average, over 2000 individuals were counted in each park, and about two thirds were sedentary when observed. More males than females used the parks, and males were twice as likely to be vigorously active. Interviewees identified the park as the most common place they exercised. Both park use and exercise levels of individuals were predicted by proximity of their residence to the park. Conclusions. Public parks are critical resources for physical activity in minority communities. Because residential proximity is strongly associated with physical activity and park use, the number and location of parks are currently insufficient to serve local populations well.
Relationship Between Number of Breast Cancer Operations Performed and 5-Year Survival After Treatment for Early-Stage Breast Cancer
Authors: Gilligan Mary Ann , Neuner Joan , Zhang Xu , Sparapani Rodney , Laud Purushottam W. , Nattinger Ann B. 
Published: February 2007

Objectives. We examined the association between number of breast cancer operations performed in a hospital (hospital volume) and all-cause and breast cancer–specific mortality using a national database and statistical methods appropriate for clustering and reducing confounding. Methods. In a retrospective cohort study, we linked Surveillance, Epidemiology, and End Results tumor registry data with Medicare claims data. The cohort included 11225 Medicare patients who had undergone surgery for early-stage breast cancer from 1994 to 1996 in 457 different hospitals. Primary outcomes were all-cause and breast cancer–specific survival rates at a mean follow-up time of 62.5 months. Results. In comparison with treatment in a low-volume hospital, treatment in a high-volume hospital was associated with hazard ratios of 0.83 (95% confidence interval [CI]=0.75, 0.92) for all-cause mortality and 0.80 (CI=0.66, 0.97) for breast cancer–specific mortality. Conclusions. An association between the volume of breast cancer operations performed in a hospital and 5-year survival rates was observed for both all-cause and breast cancer–specific mortality. Further work investigating the aspects of hospital volume that contribute to increased survival is warranted.
Lessons Learned From the Children’s Environmental Exposure Research Study
Authors: Resnik David B. , Wing Steven 
Published: February 2007

We examined 5 different ethical concerns about the Children’s Environmental Exposure Research Study and make some recommendations for future studies of exposure to hazardous environmental agents in the home. Researchers should seek community consultation and participation; make participants aware of all the risks associated with the research, including hazards discovered in the home and uncertainties about the risks of agents under investigation; and take steps to ensure that their studies will not have unfair representation of the poor or people of color. Researchers should also avoid even the appearance of a financial conflict of interest in studies that are likely to be controversial and make it clear to all parties that studies will not intentionally expose subjects to hazardous environmental agents.
Integrating Disease Control Strategies: Balancing Water Sanitation and Hygiene Interventions to Reduce Diarrheal Disease Burden
Authors: Eisenberg Joseph N.S. , Scott James C. , Porco Travis 
Published: February 2007

Objectives. Although the burden of diarrheal disease resulting from inadequate water quality, sanitation practices, and hygiene remains high, there is little understanding of the integration of these environmental control strategies. We tested a modeling framework designed to capture the interdependent transmission pathways of enteric pathogens. Methods. We developed a household-level stochastic model accounting for 5 different transmission pathways. We estimated disease preventable through water treatment by comparing 2 scenarios: all households fully exposed to contaminated drinking water and all households receiving the water quality intervention. Results. We found that the benefits of a water quality intervention depend on sanitation and hygiene conditions. When sanitation conditions are poor, water quality improvements may have minimal impact regardless of amount of water contamination. If each transmission pathway alone is sufficient to maintain diarrheal disease, single-pathway interventions will have minimal benefit, and ultimately an intervention will be successful only if all sufficient pathways are eliminated. However, when 1 pathway is critical to maintaining the disease, public health efforts should focus on this critical pathway. Conclusions. Our findings provide guidance in understanding how to best reduce and eliminate diarrheal disease through integrated control strategies.
The impact of flooding regime on the soil seed bank of flood‐meadows
Authors: Hölzel Norbert , Otte Annette 
Published: February 2007

Abstract. We assessed the significance of flooding for the floristic composition of seed banks in flood‐meadows of the northern valley of the Upper Rhine. We compared three hydrological compartments of the alluvial plain, consisting of the regularly flooded land between the river and low summer dykes (functional flood‐plain), the occasionally flooded land between summer dykes and high winter dykes (hybrid floodplain) and the land behind the winter dykes, which is now only submerged by ascending groundwater (fossil flood‐plain). Due to their different flooding regime, the three compartments should differ with respect to the prevailing conditions of diaspore input.The seed density of soil samples increased with the duration of flooding in the three compartments, while species richness and the proportion of species not occurring in the vegetation was constant. The increase in seed density can be largely attributed to an increase of disturbance indicators, which are present in the above‐ground vegetation and capable of forming a long‐term persistent seed bank.No effects of flooding on the composition of seed banks in the three flood‐plain compartments were found. The differences in seed bank composition can be largely explained by corresponding differences in above‐ground vegetation and former and present‐day meadow management. Seeds of species absent from above‐ground vegetation can be attributed to the local species pool present in the immediate vicinity of the study plots. We discuss consequences of the results for the restoration of species‐rich flood‐plain meadows.
A comparison of five distance‐based methods for spatial pattern analysis
Authors: Liu Canran 
Published: February 2007

Abstract.The behaviour of five statistics (extensions of Pielou's, Clark and Evansapos;, Pollard's, Johnson & Zimmer's, and Eberhardt's statistics, which are denoted asPi,Ce,Po,JzandEbrespectively) that involve the distance from a random point to itsjth nearest neighbour were examined against several alternative patterns (lattice‐based regular, inhomogeneous random, and Poisson cluster patterns) through Monte Carlo simulation to test their powers to detect patterns. The powers of all the five statistics increase as distance orderjincreases against inhomogeneous random pattern. They decrease forPiandCeand increase forPo,Jz, andEbagainst regular and Poisson cluster patterns.Po,Jz, andEbcan reach high powers with the third or higher order distances in most cases.However,Pois recommended because no extra information is needed, it can reach a high power with the second or third distance even though the sample size is not large in most cases, and the test can be performed with an approximateχ2distribution associated with it. When a regular pattern is expected,Jzis recommended because it is more sensitive to lattice‐based regular pattern thanPoandEb, especially for the first distance. However, simulation tests should be used because the speed of convergence ofJzto normal distribution is very slow.
La Orientación Este De Los Entierros Aborígenes En Cuevas De Cuba: Remate De Una Fábula
Authors: Corzo Gabino La Rosa 
Published: February 2007

AbstractEn Cuba, la orientación de los entierros aborígenes del período arcaico ha sido objeto de especulación e indagación por parte de numerosos especialistas. Dentro de la arqueología del Caribe ha llamado la atención la propuesta de algunos arqueólogos de la mayor de las Antillas relacionada con la dependencia del este como punto cardinal y la orientación de los cráneos de los primeros habitantes. Sin embargo, los elementos discutidos en este artículo demuestran que las orientaciones de estos entierros en cuevas generalmente se relacionan con el lugar de acceso al espacio fúnebre y las partes naturales que limitan el acceso al lugar.