bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of Threaded Versus Sintered Porous‐Surfaced Dental Implants Using Open Window or Indirect Osteotome‐Mediated Sinus Elevation: A Retrospective Report
Authors: Kermalli Jaffer Y. , Deporter Douglas A. , Lai Jim Y. , Lam Ernest , Atenafu Eshetu
Published: April 2008

Background: The purpose of this retrospective report was to evaluate the performance of dental implants placed in a teaching environment in patients requiring maxillary sinus elevation.

Methods: Threaded (acid‐washed or sand‐blasted acid‐etched) and sintered porous‐surfaced (SPS) press‐fit implants were used. Sinuses were managed using direct (open window) or indirect (osteotome‐mediated) techniques. Records were available for 97 implants in 62 patients. Preoperative subantral bone heights were determined from radiographs, primarily panoramic. Of 69 threaded implants used, 40 and 29 were placed using direct (DTH) and indirect (ITH) techniques, respectively. Twenty‐eight SPS implants were placed using the indirect technique. Implant failure rates using the Kaplan‐Meier method of analysis and cumulative crestal bone loss (the latter based on bone levels seen in the most recent radiographs) were determined for both types of implants.

Results: The mean preoperative subantral bone height for DTH implants was 5.0 mm (range, 1 to 12 mm). Preoperative bone heights for ITH implants and SPS implants placed using the indirect approach were 7.2 mm (range, 4 to 12 mm) and 4.2 mm (range, 3 to 6 mm), respectively. Significant differences in preoperative bone height were seen between DTH and ITH implants (P <0.0001) and between ITH and SPS implants (P <0.0001). Average functional times were 18.7 months and 16.3 months for DTH and ITH implants, respectively, whereas the average functional time for SPS implants was 49.9 months. Time in function was significantly greater (P <0.0001) for SPS than DTH and ITH implants. Significant differences in implant length were also seen, with SPS implants significantly shorter than DTH or ITH implants. Three implants failed to integrate, one in each of the three treatment groups, giving initial survival rates of 97.5%, 96.6%, and 96.4% for DTH, ITH, and SPS implants, respectively. Mean cumulative crestal bone loss measurements were 1.84, 1.90, and 0.57 mm for DTH, ITH, and SPS implants, respectively. Bone loss was significantly less with SPS implants than with DTH or ITH implants. A second SPS implant failed after 7 years in function, likely because of prosthetic deficiencies. This late failure reduced the Kaplan‐Meier survival rate to 80.4% for the SPS group.

Conclusion: Results from this teaching clinic suggest that the use of dental implants with sinus elevation procedures is a predictable treatment for the resorbed posterior maxilla.
Periodontal Attachment Loss in an Untreated Isolated Population of Brazil
Authors: Corraini Priscila , Baelum Vibeke , Pannuti Cláudio Mendes , Pustiglioni Alessandro Nautili , Romito Giuseppe Alexandre , Pustiglioni Francisco Emílio
Published: April 2008

Background: The aim of this study was to assess the prevalence, extent, and severity of clinical attachment loss (CAL) and to investigate the association of demographic, socioeconomic, and behavioral risk indicators with CAL in an untreated isolated population in Brazil.

Methods: All subjects aged ≥12 years were identified by a census. Participants were submitted to a full‐mouth clinical examination of six sites per tooth and were interviewed using a structured, written questionnaire.

Results: Among the 214 subjects who were interviewed and examined clinically, CAL ≥5 mm in at least one site was observed in 8% of the 12‐ to 19‐year‐olds and in all dentate subjects ≥50 years of age; the age‐dependent prevalence of CAL ≥7 mm in at least one site ranged from 5% among 12‐ to 19‐year‐olds to 83% among subjects ≥50 years old. Multivariate analysis identified plaque (odds ratio [OR] = 2.8), supragingival calculus (OR = 2.9 to 10.6), age ≥30 years (OR = 11.4), and smoking (OR = 2.4) as risk indicators for CAL ≥5 mm and smoking (OR = 8.2) as a risk indicator for CAL ≥7 mm.

Conclusions: CAL is highly prevalent in this isolated population. The high occurrence of CAL in young age groups and the confirmation of traditional risk indicators for CAL in this study suggest that other factors, such as host susceptibility, may be needed to explain the high levels of CAL found. Age and behavioral factors were risk indicators associated significantly with the CAL found in this population and may be useful indicators of high‐risk subjects for periodontal diseases.
Assessment of Parameters Affecting the Presence of the Central Papilla Using a Non‐Invasive Radiographic Method
Authors: Chang Li‐Ching
Published: April 2008

Background: This study was performed to assess the relationship between radiopaque landmarks and central papilla presence and height. The probability of the presence of a central papilla has been related to the bone crest–contact point distance. Papilla height has been measured by inserting a dental probe under local anesthesia, but this method is invasive. It would be desirable to assess the influence of other dental landmarks on the presence and height of the papilla and to use a non‐invasive method for measurement of papilla height that is simple, accurate, and accepted readily by patients.

Methods: Periapical radiographs were obtained in 310 adults with fully erupted permanent dentition, healthy gingiva (plaque and gingival indexes of 0 to 1), and well‐aligned maxillary central incisors. Semisoft radiopaque material was placed to fill the space coronal to the papilla tip, which enabled it to be visualized without probing. Vertical and horizontal distances were measured with an electric ruler.

Results: The presence of a full central papilla was related significantly to age, papillary height, and distances from the bone crest to the contact point, the buccal cemento‐enamel junction, and the proximal cemento‐enamel junction. When confounding factors were controlled using multifactorial logistic regression, the distance from the bone crest to the proximal cemento‐enamel junction was the strongest determinant of papilla presence.

Conclusions: Standard periapical radiography is a non‐invasive method that can be used to study determinants of the presence of a central papilla. The factors linked to papilla recession were age, bone crest–contact point distance, bone crest–proximal cemento‐enamel junction distance, and papilla height. Bone crest‐proximal cemento‐enamel junction distance, the strongest predictor of the probability of papilla recession, might be used to predict this probability after prosthetic or orthodontic interventions.
Site‐Specific Development of Periodontal Disease Is Associated With Increased Levels of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia in Subgingival Plaque
Authors: Mineoka Tetsuro , Awano Shuji , Rikimaru Tetsuya , Kurata Hiroshi , Yoshida Akihiro , Ansai Toshihiro , Takehara Tadamichi
Published: April 2008

Background: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia (previously T. forsythensis), which are regarded as the principal periodontopathogenic bacteria, exist as a consortium in subgingival biofilms. We aimed to examine quantitative relationships between P. gingivalis, T. denticola, and T. forsythia in subgingival biofilms and the relationship between the quantity and prevalence of these three bacteria and site‐specific periodontal health.

Methods: This study was cross‐sectional. The study population consisted of 35 adult subjects who visited the Kyushu Dental College Hospital. Plaque samples were collected from 105 periodontal pocket sites. Quantitative analyses of each of the three periodontopathogenic bacteria were performed using real‐time polymerase chain reaction with species‐specific primers and hybridization probes.

Results: The plaque samples were divided into four groups based on the presence or absence of a periodontal pocket (probing depth [PD] ≥4 mm) and bleeding on probing (BOP), regardless of attachment loss. The proportions of all three target bacteria detected in samples from sites of periodontal disease (with PD and BOP) were markedly higher than those in the other sample groups. Cell numbers of P. gingivalis, T. denticola, and T. forsythia in the subgingival plaque of each sampling site were significantly mutually correlated and were increased in the plaque of sites of periodontal disease with PD ≥4 mm and BOP.

Conclusion: The symbiotic effects of P. gingivalis, T. denticola, and T. forsythia, which coaggregate and exist concomitantly in subgingival biofilms, may be associated with the local development of periodontitis.
Free Gingival Grafts to Increase Keratinized Tissue: A Retrospective Long‐Term Evaluation (10 to 25 years) of Outcomes
Authors: Agudio Giancarlo , Nieri Michele , Rotundo Roberto , Cortellini Pierpaolo , Pini Prato Giovanpaolo
Published: April 2008

Background: Gingival augmentation procedures are indicated primarily to increase an insufficient amount of gingiva and sometimes to halt the progression of gingival recession. The aim of this retrospective long‐term study was to evaluate changes in the amount of keratinized tissue (KT) and in the position of the gingival margin after free gingival graft procedures over a period of 10 to 25 years.

Methods: One hundred three subjects presenting with 224 sites completely lacking attached gingiva associated with gingival recessions were treated in a private practice. The experimental sites were treated with gingival augmentation procedures (free gingival grafts). The grafts were positioned at the presurgical level of the gingival margin or in a submarginal position. Clinical variables, including recession depth, amount of KT, and probing depth (PD), were measured at baseline (T0), 1 year after surgery (T1), and at the end of the follow‐up period (10 to 25 years) (T2) and analyzed using descriptive statistics and multilevel models.

Results: From T0 to T1, the gingival margin shifted coronally 0.8 mm, and KT increased 4.2 mm. From T1 to T2, the gingival margin shifted coronally 0.6 mm, and the overall KT decreased 0.7 mm. PD remained stable.

Conclusion: Gingival augmentation procedures performed in sites with an absence of attached gingiva associated with recessions provide an increased amount of KT associated with recession reduction over a long period of time.
The Reproducibility of Curet Sampling of Subgingival Biofilms
Authors: Teles Flavia R. , Haffajee Anne D. , Socransky Sigmund S.
Published: April 2008

Background: Because few studies have examined the critical issue of sampling reproducibility, the purpose of the present study was to examine the reproducibility of curet sampling of subgingival biofilms.

Methods: Seven subgingival biofilm samples were taken successively, using a curet, from each of 80 sites and individually analyzed for their content of 40 bacterial species using checkerboard DNA‐DNA hybridization. One healthy site was sampled in each of 20 periodontally healthy subjects, and one sulcus/pocket of ≤3, 4 to 5, and ≥6 mm was sampled in each of 20 subjects with chronic periodontitis. The significance of differences in counts and proportions of individual species at the seven successive samplings for each probing depth (PD) category was determined using the Kruskal‐Wallis test. The reproducibility of species proportions at each PD category was measured using the coefficient of variation (CV), and the consistency of microbial profiles across samples was examined using the minimum similarity coefficient.

Results: There was no significant difference in the mean proportions of the 40 test species in the seven successive samples in each of the four PD categories. The median CV for individual species in the same site was 0.79 (95% confidence interval [CI]: 0.76 to 0.82) compared to 1.76 (95% CI: 1.69 to 1.82) in samples from different sites. The within‐site mean minimum similarity coefficient (± SEM) was 51.2% ± 2.2%, and it was 27.9% ± 0.3% between sites.

Conclusion: The proportions of species remained consistent in successive curet samples, indicating that the use of curets provided a reliable and reproducible method to obtain subgingival samples.
Renal Alterations in Prediabetic Rats With Periodontitis
Authors: Pontes Andersen Carla C. , Holmstrup Palle , Buschard Karsten , Flyvbjerg Allan
Published: April 2008

Background: Periodontitis was shown to have an impact on glucose levels in prediabetic and diabetic rats. The Zucker fatty rat (ZFR) is a well‐characterized model of prediabetes presenting with impaired glucose tolerance, hyperinsulinemia, dyslipidemia, and moderate hypertension. The aim of the present study was to investigate whether periodontitis influences kidney changes in ZFRs.

Methods: Male adult ZFRs (N = 19) and their lean littermates (N = 18) were studied. Periodontitis was induced with ligatures in half of the ZFRs and lean rats, whereas the other half served as controls. After 4 weeks, the rats were sacrificed, and the kidneys, liver, and heart were removed and weighed. Kidneys were evaluated histologically for glomerular volume and renal mRNA levels of vascular endothelial growth factor (VEGF), VEGF receptor 2, transforming growth factor‐beta, connective tissue growth factor, collagen IVα1, fibronectin, and nephrin. Urinary albumin excretion and creatinine clearance were also evaluated.

Results: In prediabetic ZFRs, periodontitis was associated with kidney hypertrophy (P = 0.03) and a tendency for increased glomerular volume (P = 0.06). In lean littermates, elevated fibronectin mRNA levels (P = 0.03) were noted in the presence of periodontitis.

Conclusion: Our findings suggest the participation of periodontitis in the development of early renal changes in ZFRs.
Efficacy of Platelet‐Rich Plasma on Wound Healing in Rabbits
Authors: Lee Hung‐Wen , Reddy Michael S. , Geurs Nicolaas , Palcanis Kent G. , Lemons Jack E. , Rahemtulla Firoz G. , Ho Kang‐Jey , Chen Dung‐Tsa , Davis Cara R. , Feldman Dale S.
Published: April 2008

Background: The purpose of this study was to evaluate if the healing of full‐thickness skin wounds was accelerated by platelet‐rich plasma (PRP).

Methods: Four 2.5 × 2.5‐cm full‐thickness skin wounds were created on the backs of 15 New Zealand white rabbits. One wound on each animal received 0.3, 0.6, or 0.9 ml PRP, and the fourth wound served as a control. Seven and eight animals were sacrificed after 1 or 2 weeks, respectively, to determine histomorphometrically the epithelialization rate, contraction rate, healing rate, tissue fill, and volume fractions of fibroblasts, neutrophils, macrophages, and blood vessels.

Results: Only the 0.6‐ and 0.9‐ml groups had significantly lower contraction rates than the controls after 2 weeks (P <0.05). Although no statistically significant differences were found in other parameters between the PRP‐treated wounds and the controls, the PRP treatment led to increases in average epithelialization rates and volume fraction of blood vessels at both time periods. The PRP also seemed to have the most positive effect on healing rate, tissue fill, and volume fraction of fibroblasts during week 1 compared to week 2.

Conclusions: The PRP treatment enhanced healing in full‐thickness wounds by reducing the contraction rate with a trend toward acceleration of the epithelial migration and the angiogenic response. Further studies with larger sample sizes should be conducted to improve statistical sensitivity. Longer time intervals and modifications of PRP volume should also be explored to evaluate the long‐term efficacy of PRP on wound healing.
Interleukin‐6 Polymorphisms Are Associated With Pathogenic Bacteria in Subjects With Periodontitis
Authors: Nibali Luigi , Tonetti Maurizio S. , Ready Derren , Parkar Mohamed , Brett Peter M. , Donos Nikos , D'Aiuto Francesco
Published: April 2008

Background: Growing evidence suggests that individual genetic susceptibility may influence the host's response to infections. Previously, we showed that a common variation in the interleukin (IL)‐6 gene was associated with increased odds of detection of common periodontal pathogens from individuals with aggressive periodontitis. The aim of this study was to investigate the association between IL‐6 polymorphisms and periodontopathogenic bacteria in a larger, ethnically mixed population of subjects with periodontitis.

Methods: Genomic DNA was extracted from 107 subjects diagnosed with severe forms of periodontitis to study a cluster of polymorphisms in inflammatory genes, including IL‐6. The presence of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and Tannerella forsythia (previously T. forsythensis) in their subgingival biofilm was determined by polymerase chain reaction analysis. Serum IL‐6 and C‐reactive protein (CRP) concentrations were analyzed by enzyme‐linked immunosorbent assay.

Results: Multiple logistic regression analysis revealed that the IL‐6 −6106 polymorphism was associated with the detection of A. actinomycetemcomitans (P = 0.009; odds ratio [OR] = 3.5; 95% confidence interval [CI]: 1.38 to 9.16) and the concomitant detection of A. actinomycetemcomitans and P. gingivalis (P = 0.015; OR = 3.6; 95% CI: 1.28 to 10.04). The IL‐6 −174 polymorphism was associated with increased odds of the concomitant detection of A. actinomycetemcomitans and P. gingivalis (P = 0.042; OR = 2.8; 95% CI: 1.04 to 7.75). Haplotype analysis of all five IL‐6 polymorphisms confirmed an association with the detection of A. actinomycetemcomitans (P = 0.046). The IL‐6 −6106 polymorphism was also associated with CRP serum levels at multivariate analysis (P = 0.024).

Conclusions: These findings confirm the hypothesis that complex interactions between the microbiota and host genome are at the basis of susceptibility to periodontitis. Periodontal disease may represent a useful model to study the pathways and mechanisms of host–pathogen interactions in inflammatory diseases.
Effect of Platelet‐Rich Plasma on the Healing of Intrabony Defects Treated With Beta Tricalcium Phosphate and Expanded Polytetrafluoroethylene Membranes
Authors: Döri Ferenc , Huszár Tamás , Nikolidakis Dimitris , Tihanyi Dora , Horváth Attila , Arweiler Nicole B. , Gera István , Sculean Anton
Published: April 2008

Background: Regenerative periodontal therapy using platelet‐rich plasma (PRP) and different types of bone substitutes with or without guided tissue regeneration (GTR) has been proposed as a modality to enhance the outcome of regenerative surgery. However, there are limited data from controlled clinical studies evaluating the effect of PRP on the healing of deep intrabony defects treated with a combination of bone substitutes and GTR. The aim of this study was to clinically evaluate the effect of PRP on the healing of deep intrabony defects treated with beta tricalcium phosphate (β‐TCP) and GTR by means of a non‐bioresorbable expanded polytetrafluoroethylene membrane.

Methods: Twenty‐eight subjects with advanced chronic periodontal disease and displaying one intrabony defect were treated randomly with a combination of PRP + β‐TCP + GTR or β‐TCP + GTR. Plaque index, gingival index, bleeding on probing, probing depth (PD), gingival recession, and clinical attachment level (CAL) were evaluated at baseline and at 1 year after treatment. CAL was the primary outcome variable.

Results: No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all subjects. At 1 year after therapy, the sites treated with PRP + β‐TCP + GTR showed a reduction in mean PD from 9.1 ± 0.6 mm to 3.3 ± 0.5 mm (P <0.001) and a change in mean CAL from 10.1 ± 1.3 mm to 5.7 ± 1.1 mm (P <0.001). In the group treated with β‐TCP + GTR, mean PD was reduced from 9.0 ± 0.8 mm to 3.6 ± 0.9 mm (P <0.001), and the mean CAL changed from 9.9 ± 1.0 mm to 5.9 ± 1.2 mm (P <0.001). In both groups, all sites gained ≥3 mm of CAL. CAL gains ≥4 mm were noted in 86% (12 of 14 defects) of the cases treated with PRP + β‐TCP + GTR and in 79% (11 of 14 defects) of those treated with β‐TCP + GTR. No statistically significant differences in any of the investigated parameters were observed between the two groups at the 1‐year reevaluation.

Conclusion: At 1 year after surgery, both therapies resulted in significant PD reductions and CAL gains.
Improved Cooperation Between Service Company and Operator for Faster Development of Better Tools
Authors: Koenig M. , McLaughlin S.
Published: April 2008

The present paper describes the prize to be gained when thorough feedback and co-operation between operator and service company are made a priority during the application of new tools in the oilfield. A real life example is provided to highlight how solution driven discussion and prompt detailed data sharing can enable service companies to develop new tools faster and cheaper to satisfy operator needs of tool reliability and accuracy.

In July 2007, BP field-tested the impact tool during a memory PLT campaign in an onshore oilfield, UK. The impact tool is a memory gauge that is capable of logging downhole P/T information, tool-string angle and bi-directional impact resulting from jarring activities.

While this trial was the first-time run of this tool within BP, across the industry it was the third application just in the North Sea. Yet during the job it became obvious that there was a need for further improvement of the tool in areas of tool function and set-up. Intensive discussion with the tool-provider on future enhancements of the tool commenced while operations were still going on. Based on this close co-operation, the vendor was able to develop solutions and implement them in the tool within weeks.

The paper will provide insights into the project planning, share the relevant details of the operational phase and conclude with the obtained learning which lead to the enhancement of the impact tool. Since implementation of the modifications, the tool has shown excellent results and outstanding performance in recent field-operations.
Chemical Engineering via Art
Authors: Tamir Abraham
Published: April 2008

The major aim of this article is to demonstrate via art different aspects of Chemical Engineering. This is a new
approach developed by the author to describe scientific and engineering subjects via art, thus making them more understandable
and easy to percept. The author has reached this conclusion after teaching several times a course on “The Interaction
Between Art and Science” as well as writing articles in several scientific journals.
In vitro evaluation of the effect of trans-10, cis-12 conjugated linoleic acid on phagocytosis by canine peripheral blood polymorphonuclear neutrophilic leukocytes exposed to methylprednisolone sodium succinate
Authors: Kang Ji-Houn , Yang Mhan-Pyo
Published: April 2008

Objective—To examine whether in vitro treatment with trans-10, cis-12 conjugated linoleic acid (t10c12-CLA) restores the phagocytic capacity and oxidative burst activity (OBA) of canine polymorphonuclear neutrophilic leukocytes (PMNs) exposed to methylprednisolone sodium succinate (MPSS).

Sample Population—Peripheral blood PMNs obtained from 12 healthy Beagles.

Procedures—The experimental design involved administration of a high dose of MPSS, which is the recommended protocol for dogs with acute spinal cord injury. To evaluate PMN function, blood samples were collected from dogs before IV injections of doses of MPSS or saline (0.9% NaCl) solution (time 0) and 2, 12, and 24 hours after injections ceased. Polymorphonuclear neutrophilic leukocytes were isolated from blood samples and incubated with t10c12-CLA alone or t10c12-CLA in combination with N-acetylcysteine (an antioxidant agent). Phagocytic capacity and OBA were measured simultaneously by use of flow cytometry.

Results—The phagocytic capacity and OBA of PMNs were suppressed by IV injection of MPSS and restored 12 hours after injection ceased. In vitro treatment with t10c12-CLA enhanced the phagocytic capacity and OBA of PMNs, regardless of whether dogs had been treated with MPSS. Effects of t10c12-CLA on OBA were detected only when phagocytosis was stimulated by microspheres. Use of N-acetylcysteine attenuated the stimulatory effects of t10c12-CLA.

Conclusions and Clinical Relevance—Exposure to t10c12-CLA enhanced the phagocytic capacity and OBA of canine PMNs, and this effect may have involved t10c12-CLA–induced generation of reactive oxygen species.
Effects of small intestinal ischemia and reperfusion on expression of tumor necrosis factor-α and interleukin-6 messenger RNAs in the jejunum, liver, and lungs of dogs
Authors: Nezu Yoshinori , Nezu Yoko , Shigihara Kae , Harada Yasuji , Yogo Takuya , Hara Yasushi , Tagawa Masahiro
Published: April 2008

Objective—To determine the effects of intestinal ischemia and reperfusion on the expression of tumor necrosis factor (TNF)-α and interleukin (IL)-6 mRNAs in the jejunum, liver, and lungs of dogs.

Animals—8 healthy adult Beagles.

Procedures—In each dog, the cranial mesenteric artery was occluded for 0 (control group; n = 4) or 60 (I-R group; 4) minutes, followed by reperfusion for 480 minutes; serum TNF-α and IL-6 activities and expression levels of TNF-α and IL-6 mRNAs in jejunal, hepatic, and lung tissues were measured before and at the end of the ischemic period and at intervals during reperfusion. For each variable, values were compared between the control and I-R groups at each time point.

Results—Compared with the control group, serum IL-6 activity increased significantly after 180 minutes of reperfusion in the I-R group; also, jejunal TNF-α mRNA expression increased significantly after 60 (peak) and 180 minutes of reperfusion. In the I-R group, expressions of IL-6 mRNA in the liver and TNF-α and IL-6 mRNAs in the lungs increased significantly at 480 minutes of reperfusion, compared with the control group. Serum TNF-α activity, expression of IL-6 mRNA in the jejunum, and expression of TNF-α mRNA in the liver in the control and I-R groups did not differ.

Conclusions and Clinical Relevance—Results indicated that the liver, lungs, and jejunum contributed to the production of TNF-α and IL-6 after intestinal ischemia and reperfusion in dogs, suggesting that intestinal ischemia and reperfusion induce a systemic proinflammatory cytokine response in dogs.
Biological activity of dihydroartemisinin in canine osteosarcoma cell lines
Authors: Hosoya Kenji , Murahari Sridhar , Laio Albert , London Cheryl A. , Couto C. Guillermo , Kisseberth William C.
Published: April 2008

Objective—To evaluate the biological activity of dihydroartemisinin on canine osteosarcoma cell lines in vitro.

Sample Population—4 canine osteosarcoma cell lines.

Procedures—Cell viability assays were performed on canine osteosarcoma cell lines OSCA2, OSCA16, OSCA50, and D17 after 24, 48, and 72 hours of treatment with dihydroartemisinin at concentrations of 0.1 to 100μM. Apoptosis was assessed by use of an ELISA for free nuclosomal DNA fragmentation and by western blot analysis for cleavage of caspase 3. Cell cycle analysis was performed by use of staining with propidium iodide and flow cytometry. Detection of reactive oxygen species (ROS) was conducted in the D17 cell line by use of 6-carboxy-2′,7′-dihydrofluorescein diacetate and flow cytometry.

Results—The concentration of dihydroartemisinin required for 50% inhibition of cell viability (IC50) was achieved in all 4 canine osteosarcoma cell lines and ranged from 8.7 to 43.6μM. Induction of apoptosis was evident as an increase in nucleosomal DNA fragmentation, cleavage of caspase 3, and an increase in the population in the sub G0/G1 phase of the cell cycle detected by flow cytometry. Exposure to dihydroartemisinin also resulted in a decrease in the G0/G1 population. Iron-dependent generation of ROS was detected in dihydroartemisinin-treated D17 cells; ROS generation increased in a dose-dependent manner.

Conclusions and Clinical Relevance—Incubation with dihydroartemisinin resulted in biological activity against canine osteosarcoma cell lines, which included induction of apoptosis and arrest of the cell cycle. Clinical trials of dihydroartemisinin in dogs with osteosarcoma should be conducted.
Pharmacokinetics of remifentanil in conscious cats and cats anesthetized with isoflurane
Authors: Pypendop Bruno H. , Brosnan Robert J. , Siao Kristine T. , Stanley Scott D.
Published: April 2008

Objective—To characterize the pharmacokinetics of remifentanil in conscious cats and cats anesthetized with isoflurane.

Animals—6 cats.

Procedures—Remifentanil (1 μg/kg/min for 5 minutes) was administered IV in conscious cats or cats anesthetized with 1.63% isoflurane in oxygen in a randomized crossover design. Blood samples were obtained immediately prior to remifentanil administration and every minute for 10 minutes, every 2 minutes for 10 minutes, and every 5 minutes for 10 minutes after the beginning of the infusion. Blood was immediately transferred to tubes containing citric acid, flash frozen in liquid nitrogen, and stored at −80°C until analysis. Blood remifentanil concentration was determined by use of liquid chromatography–mass spectrometry. Remifentanil concentration-time data were fitted to compartment models.

Results—A 2-compartment model (with zero-order input because of study design) best described the disposition of remifentanil in awake and isoflurane-anesthetized cats. The apparent volume of distribution of the central compartment, the apparent volume of distribution at steady state, the clearance, and the terminal half-life (median [range]) were 1,596 (1,164 to 2,111) and 567 (278 to 641) mL/kg, 7,632 (2,284 to 76,039) and 1,651 (446 to 29,229) mL/kg, 766 (408 to 1,473) and 371 (197 to 472) mL/min/kg, and 17.4 (5.5 to 920.3) and 15.7 (3.8 to 410.3) minutes in conscious and anesthetized cats, respectively.

Conclusions and Clinical Relevance—The disposition of remifentanil in cats was characterized by a high clearance. Isoflurane anesthesia significantly decreased the volume of the central compartment, likely by decreasing blood flow to vessel-rich organs.
Pyogranulomatous cystitis associated with Toxoplasma gondii infection in a cat after renal transplantation
Authors: Nordquist Barbro C. , Aronson Lillian R.
Published: April 2008

Case Description—An 8-year-old spayed female domestic shorthair cat was evaluated for azotemia and a suspected mass in the urinary bladder 6 weeks after receiving a renal transplant. Ultrasonography revealed a mass at the ureteroneocystostomy site, and the mass was excised. Both the donor and recipient cats were seronegative for Toxoplasma gondii–specific IgG antibodies prior to transplantation.

Clinical Findings—Histologic evaluation of the mass revealed lesions indicative of extensive necrotizing pyogranulomatous cystitis with numerous intralesional T gondii tachyzoites and bradyzoite cysts.

Treatment and Outcome—Treatment with clindamycin was initiated; however, the cat's clinical condition continued to decline, and it was euthanized 9 days after the mass was excised. Necropsy revealed T gondii cysts within the renal allograft and the transplanted ureter, with no evidence of systemic spread of organisms.

Clinical Relevance—Toxoplasmosis should be considered as a differential diagnosis for azotemia in feline renal transplant recipients regardless of the results of assays for T gondii antibodies in the serum of donors or recipients. This report illustrated the need for improved screening of donor and recipient cats and the importance of minimizing exposure to potential sources of T gondii after transplantation.
Effects of study design and analysis on the spatial community structure detected by multiscale ordination
Authors: Schlup Barbara M. , Wagner Helene H.
Published: April 2008

Question:

What are the effects of different aspects of data collection and analysis on the spatial partitioning of ordination results by multiscale ordination?

Locations:

Heterogeneous pasture at Marchairuz in the Jura mountains, Switzerland and Mixed hardwood‐pine forest in Oostings Natural Area, NC, USA.

Methods:

We evaluated the efficiency of different sampling designs for identifying the spatial structure of plant communities and analysed two datasets with multiscale ordination. We compared the effects of quadrat size, the number of species included in the analysis, data type, detrending and ordination method on the shape and precision of the community variogram summarizing spatial community structure.

Results:

A three‐block sampling design provided a more even distribution of the number of pairs of observation per distance class than random, transect or grid designs. The precision of variogram estimates depended more strongly on the number of species than on the number of quadrats. In contrast, the choice of data type (abundance transformation) had little influence on the shape of the variogram. Detrending reduced the range of spatial autocorrelation. An increase in quadrat size resulted in a smoother variogram and stronger spatial autocorrelation. Principal components analysis (PCA) and Redundancy analysis (RDA) resulted in a larger range of spatial autocorrelation values than did Correspondence analysis (CA) and Canonical correspondence analysis (CCA), but the shape of the variograms was similar.

Conclusion:

Random samples as well as transects and regular grids may not be efficient sampling designs for spatial analysis of community structure. While the number of species considered strongly affects the precision of a community variogram, its shape depends on the size of the sampling units. Earlier studies may have overestimated the spatial scale of internal organization in plant communities.
Rare interstitial deletion 9q31.2 to q33.1 de novo: Longitudinal study in a patient over a period of more than 20 years
Authors: Gamerdinger Ulrike , Eggermann Thomas , Schubert Regine , Schwanitz Gesa , Kreiß‐Nachtsheim Martina
Published: April 2008

The female carrier of a de novo interstitial deletion 9q [karyotype 46,XX,del(9)(q31.2q33.1)] was followed up over a period of more than 20 years. She shows facial dysmorphisms and significant growth retardation. Motor abilities are restricted by muscular hypotonia and malposition of the feet. She has mental retardation. There was no speech development and phases of autism were reported. By analyses with FISH and short tandem repeat markers, the interstitial deletion was confirmed and characterized to span 9q31.2q33.1, comprising at least 7.07 Mb. The aberration is of paternal origin. © 2008 Wiley‐Liss, Inc.
Problems in determination of skeletal lead burden in archaeological samples: An example from the First African Baptist Church population
Authors: Wittmers L.E. , Aufderheide A.C. , Pounds J.G. , Jones K.W. , Angel J.L.
Published: April 2008

Human bone lead content has been demonstrated to be related to socioeconomic status, occupation and other social and environmental correlates. Skeletal tissue samples from 135 individuals from an early nineteenth century Philadelphia cemetery (First African Baptist Church) were studied by electrothermal atomic absorption spectrometry and X‐ray fluorescence for lead content. High bone lead levels led to investigation of possible diagenetic effects. These were investigated by several different approaches including distribution of lead within bone by X‐ray fluorescence, histological preservation, soil lead concentration and acidity as well as location and depth of burial. Bone lead levels were very high in children, exceeding those of the adult population that were buried in the cemetery, and also those of present day adults. The antemortem age‐related increase in bone lead, reported in other studies, was not evidenced in this population. Lead was evenly deposited in areas of taphonomic bone destruction. Synchrotron X‐ray fluorescence studies revealed no consistent pattern of lead microdistribution within the bone. Our conclusions are that postmortem diagenesis of lead ion has penetrated these archaeological bones to a degree that makes their original bone lead content irretrievable by any known method. Increased bone porosity is most likely responsible for the very high levels of lead found in bones of newborns and children. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
Non‐invasive mass transfer measurements in complex biofilm‐coated structures
Authors: Graf von der Schulenburg D.A. , Akpa B.S. , Gladden L.F. , Johns M.L.
Published: April 2008

We demonstrate a novel application of 13C pulsed field gradient (PFG) NMR to monitor mass transfer, due to both flow and diffusion, in a 3D complex porous support structure modified by biofilm growth. This enables timescales an order of magnitude larger than previously possible to be accessed with respect to displacement probability distribution (propagator) measurements. The evolution in the propagator shape with observation time to the Gaussian asymptote (constant dispersion coefficient) is consequently well resolved. We also simulated the measured displacement propagators with good agreement between experiment and prediction. The methodology has significant potential for the selective characterization of the transport of nutrients, metabolic products, pollutants and biocides in such complex biofilm‐containing structures. Biotechnol. Bioeng. 2008;101: 602–608. © 2008 Wiley Periodicals, Inc.
Kinetic modeling of enzymatic hydrolysis of cellulose in differently pretreated fibers from dairy manure
Authors: Liao Wei , Liu Yan , Wen Zhiyou , Frear Craig , Chen Shulin
Published: April 2008

A kinetic model incorporating dynamic adsorption, enzymatic hydrolysis, and product inhibition was developed for enzymatic hydrolysis of differently pretreated fibers from a nitrogen‐rich lignocellulosic material—dairy manure. The effects of manure proteins on the enzyme adsorption profile during hydrolysis have been discussed. Enzyme activity, instead of protein concentration, was used to describe the enzymatic hydrolysis in order to avoid the effect of manure protein on enzyme protein analysis. Dynamic enzyme adsorption was modeled based on a Langmiur‐type isotherm. A first‐order reaction was applied to model the hydrolysis with consideration being given for the product inhibition. The model satisfactorily predicted the behaviors of enzyme adsorption, hydrolysis, and product inhibition for all five sample manure fibers. The reaction conditions were the substrate concentrations of 10–50 g/L, enzyme loadings of 7–150 FPU/g total substrate, and the reaction temperature of 50°C. Biotechnol. Bioeng. 2008;101: 441–451. © 2008 Wiley Periodicals, Inc.
Molecularly targeted therapy and cancer surgery
Authors: Judson I , Barriuso J
Published: April 2008

May reduce micrometastases
Dipeptide Derivatives of AZT: Synthesis, Chemical Stability, Activation in Human Plasma, hPEPT1 Affinity, and Antiviral Activity
Authors: Santos Cledir , Morais José , Gouveia Luís , de Clercq Erik , Pannecouque Christophe , Nielsen Carsten Uhd , Steffansen Bente , Moreira Rui , Gomes Paula
Published: April 2008

5′‐O‐Dipeptide ester prodrugs of antiviral zidovudine (AZT) were designed to target the human intestinal oligopeptide transporter, hPEPT1, and were evaluated for their stability at pH 7.4 in buffer and in human plasma, affinity toward hPEPT1, cytotoxicity, and antiretroviral activity. The dipeptide esters of AZT undergo cyclization in buffer at pH 7.4 to release the parent drug at a rate that depends on the size of the side chains of the peptide carrier; the prodrug is considerably more stable if bulky β‐branched amino acids such as Ile and Val are present, particularly as C‐terminal residues. Incubation in human plasma showed that most of the dipeptide esters of AZT release the parent drug through two aminopeptidase‐mediated pathways: 1) stepwise cleavage of each of the amino acids and 2) direct cleavage of the dipeptide–drug ester bond. However, the plasma hydrolysis of Gly‐Gly‐AZT and Phe‐Gly‐AZT showed only direct cleavage of the dipeptide–drug ester bond. Substrate half‐lives in plasma were again remarkably high when hydrophobic β‐branched amino acids (Val, Ile) were present. The esters were also good substrates for the intestinal oligopeptide transporter hPEPT1 in vitro, with Val‐Gly‐AZT and Val‐Ala‐AZT presenting the highest affinity toward the transporter (IC50: 0.20 and 0.15 mM, respectively). The AZT dipeptide esters were assayed against the IIIB and ROD strains of HIV, and their cytotoxicity was evaluated in MT‐4 cells. The selectivity index of the prodrugs was two‐ to threefold higher than that of AZT for all compounds analyzed. These results point to the potential of dipeptide‐based carriers for the development of effective antiviral drug‐delivery systems. Val‐Ala‐AZT appears to combine chemical stability with good affinity for the hPEPT1 transporter and an improved cytotoxicity/antiretroviral index relative to AZT.
CD11c/EYFP transgene illuminates a discrete network of dendritic cells within the embryonic, neonatal, adult, and injured mouse brain
Authors: Bulloch Karen , Miller Melinda M. , Gal‐Toth Judit , Milner Teresa A. , Gottfried‐Blackmore Andres , Waters Elizabeth M. , Kaunzner Ulrike W. , Liu Kang , Lindquist Randall , Nussenzweig Michel C. , Steinman Ralph M. , McEwen Bruce S.
Published: April 2008

The CD11c enhanced yellow fluorescent protein (EYFP) transgenic mouse was constructed to identify dendritic cells in the periphery (Lindquist et al. [2004] Nat. Immunol. 5:1243–1250). In this study, we used this mouse to characterize dendritic cells within the CNS. Our anatomic results showed discrete populations of EYFP+ brain dendritic cells (EYFP+ bDC) that colocalized with a small fraction of microglia immunoreactive for Mac‐1, Iba‐1, CD45, and F4/80 but not for NeuN, Dcx, NG2 proteoglycan, or GFAP. EYFP+ bDC, isolated by fluorescent activated cell sorting (FACS), expressed mRNA for the Itgax (CD11c) gene, whereas FACS anlaysis of EYFP+ bDC cultures revealed the presence of CD11c protein. Light microscopy studies revealed that EYFP+ bDC were present in the embryonic CNS when the blood–brain barrier is formed and postnatally when brain cells are amenable to culturing. In adult male mice, EYFP+ bDC distribution was prominent within regions of the CNS that 1) are subject to structural plasticity and neurogenesis, 2) receive sensory and humoral input from the external environment, and 3) lack a blood–brain barrier. Ultrastructural analysis of EYFP+ bDC in adult neurogenic niches showed their proximity to developing neurons and a morphology characteristic of immune/microglia cells. Kainic acid‐induced seizures revealed that EYFP+ bDC responded to damage of the hippocampus and displayed morphologies similar to those described for seizure‐activated EGFP+ microglia in the hippocampus of cfms (CSF‐1R) EGFP mice. Collectively, these findings suggest a new member of the dendritic cell family residing among the heterogeneous microglia population. J. Comp. Neurol. 508:687–710, 2008. © 2008 Wiley‐Liss, Inc.
Erasure of the paternal transcription program during spermiogenesis: The first step in the reprogramming of sperm chromatin for zygotic development
Authors: Zheng Junke , Xia Xiaoyu , Ding Hui , Yan Ayong , Hu Shaunggang , Gong Xun , Zong Shudong , Zhang Yonglian , Sheng Hui Z.
Published: April 2008

Male germ cells possess a unique epigenetic program and express a male‐specific transcription profile. However, when its chromatin is passed onto the zygote, it expresses an transcription/epigenetic program characteristic of the zygote. The mechanism underlying this reprogramming process is not understood at present. In this study, we show that an extensive range of chromatin factors (CFs), including essential transcription factors and regulators, remodeling factors, histone deacetylases, heterochromatin‐binding proteins, and topoisomerases, were removed from chromatin during spermiogenesis. This process will erase the paternal epigenetic program to generate a relatively naive chromatin, which is likely to be essential for installation of the zygotic developmental program after fertilization. We have also showed that transcription termination in male germ cells was temporally correlated with CF dissociation. A genome‐wide CF dissociation will inevitably disassemble the transcription apparatus and regulatory mechanism and lead to transcription silence. Based on data presented in this and previous studies (Sun et al., Cell Research [2007] 17:117–134), we propose that paternal‐zygotic transcription reprogramming begins with a genome‐wide CF dissociation to erase the existing transcription program in later stages of spermatogenesis. This will be followed by assembling of the zygotic equivalent after fertilization. The transcription/epigenetic program of the male germ cell is transformed into a zygotic one using an erase‐and‐rebuild strategy similar to that used in the maternal‐zygotic transition. It is also noted that transcription is terminated long after meiosis is completed and before chromatin becomes highly condensed during spermatogenesis. The temporal order of these events suggests that transcription silence does not have to be coupled to meiosis or chromatin condensation. Developmental Dynamics 237:1463‐1476, 2008. © 2008 Wiley‐Liss, Inc.
Reconceptualizing relative deprivation in the context of dramatic social change: the challenge confronting the people of Kyrgyzstan
Authors: de la Sablonnière Roxane , Taylor Donald M. , Perozzo Cristina , Sadykova Nazgul
Published: March 2008

The present study investigated the relationship between Temporal Collective Relative Deprivation and collective well‐being in the context of dramatic social change in Kyrgyzstan. Traditional research has evaluated Temporal Collective Relative Deprivation by comparing a group's present situation to a point in the recent past or future. We argue that a reconceptualization of Temporal Collective Relative Deprivation is needed. We hypothesized, first, that examining several, as opposed to a single, points of comparison will better predict collective well‐being. Secondly, we hypothesized that the points of comparison that will best predict collective well‐being will not necessarily correspond to the most recent past or future. Third, we hypothesized that the overall trajectory of Temporal Collective Relative Deprivation perceived across time will influence the level of collective well‐being. A sample of 565 Kyrgyz participants completed a questionnaire. Hierarchical regressions and group‐based trajectory modeling confirmed our three hypotheses. Theoretical and methodological implications of the findings are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Group motives in threatening contexts: When a loyalty conflict paradoxically reduces the influence of an anti‐discrimination ingroup norm
Authors: Falomir‐Pichastor Juan M. , Gabarrot Fabrice , Mugny Gabriel
Published: March 2008

The influence of pro‐ versus anti‐discrimination ingroup norms on Swiss nationals' attitudes towards foreigners was investigated as a function of national identification and perceived material ingroup threat. As predicted, results revealed a significant interaction between identification and threat: High identifiers showed a more negative attitude than low identifiers mainly when perceived threat was high. In other words, high identifiers conformed to the pro‐discrimination norm, but showed a counter‐conformity effect for the anti‐discrimination norm. Additional results revealed that high identifiers actually disagreed with the anti‐discrimination norm when perceived threat was high, but that they were more attached to the ingroup. These findings suggest that when the ingroup norm is not an appropriate response to an ingroup threat (i.e. anti‐discrimination norm), high identifiers find themselves in a loyalty conflict: they are unable to simultaneously conform to the group norm and protect the group. This conflict was resolved through a compensatory mechanism: High identifiers distanced themselves from the ingroup norm in order to protect the group (i.e. by increasing negative attitudes towards foreigners) but reinforced other ingroup ties (i.e. by increasing attachment to the ingroup values). Copyright © 2008 John Wiley & Sons, Ltd.