bluuebunny/crossref_metadata_2025 huggingface dataset:
MEPE-ASARM Peptides Control Extracellular Matrix Mineralization by Binding to Hydroxyapatite: An Inhibition Regulated by PHEX Cleavage of ASARM
Authors: Addison William N , Nakano Yukiko , Loisel Thomas , Crine Phillippe , McKee Marc D
Published: July 2008

Hyp mice having an inactivating mutation of the phosphate-regulating gene with homologies to endopeptidases on the X-chromosome (Phex) gene have bones with increased matrix extracellular phosphoglycoprotein (MEPE). An acidic, serine- and aspartic acid–rich motif (ASARM) is located in the C terminus of MEPE and other mineralized tissue matrix proteins. We studied the effects of ASARM peptides on mineralization and how PHEX and MEPE interactions contribute to X-linked hypophosphatemia (XLH). ASARM immunoreactivity was observed in the osteoid of wildtype bone and in the increased osteoid of Hyp mice. In wildtype bone, PHEX immunostaining was found particularly in osteoid osteocytes and their surrounding matrix. Treatment of MC3T3-E1 osteoblasts with triphosphorylated (3 phosphoserines) ASARM peptide (pASARM) caused a dose-dependent inhibition of mineralization. pASARM did not affect collagen deposition or osteoblast differentiation, suggesting that pASARM inhibits mineralization by direct binding to hydroxyapatite crystals. Binding of pASARM to mineralization foci in pASARM-treated cultures and to synthetic hydroxyapatite crystals was confirmed by colloidal-gold immunolabeling. Nonphosphorylated ASARM peptide showed little or no binding to hydroxyapatite and did not inhibit mineralization, showing the importance of ASARM phosphorylation in regulating mineralization. PHEX rescued the inhibition of osteoblast culture mineralization by pASARM, and mass spectrometry of cleaved peptides obtained after pASARM-PHEX incubations identified pASARM as a substrate for PHEX. These results, showing that pASARM inhibits mineralization by binding to hydroxyapatite and that this inhibitor can be cleaved by PHEX, provide a mechanism explaining how loss of PHEX activity can lead to extracellular matrix accumulation of ASARM resulting in the osteomalacia of XLH.
Heteroscedastic Regression Analysis of Factors Affecting BMD Monitoring
Authors: Sadatsafavi Mohsen , Moayyeri Alireza , Wang Liqun , Leslie William D
Published: July 2008

Identifying factors affecting BMD precision and interindividual heterogeneity in BMD change can help optimize BMD monitoring. BMD change for the lumbar spine and total hip for short-term reproducibility (n = 328) and long-term clinical monitoring (n = 2720) populations were analyzed with heteroscedastic regression using linear prediction for mean (monitoring population only) and log-linear prediction for SD (both populations). For clinical monitoring, male sex, baseline body mass index (BMI), and systemic corticosteroid use were associated with greater SD of BMD change. Weight gain was negatively associated with SD for the hip, whereas height change was positively associated with SD for the spine. Each additional year of monitoring increased the SD by 6.5–9.2%. Osteoporosis treatment affected mean change but did not increase dispersion. For short-term reproducibility, performing scans on a different day increased the SD of measurement error by 38–44%. Baseline BMD, difference in bone area, and a repeat scan performed by different technologists were associated with higher measurement error only for the hip. For both samples, heteroscedastic regression outperformed models that assumed homogeneous variance. Heteroscedastic regression techniques are powerful yet underused tools in analyzing longitudinal BMD data and can be used to generate individualized predictions of BMD change and measurement error.
Long-Term Survival and Fracture Risk After Hip Fracture: A 22-Year Follow-Up in Women
Authors: von Friesendorff My , Besjakov Jack , Åkesson Kristina
Published: July 2008

Hip fracture is associated with high early mortality. Little is known about long-term survival and subsequent fracture risk. The aim of this study was to evaluate survival and fracture risk after hip fracture in women at different ages. All women suffering a hip fracture during 1984–1985 in Malmö, Sweden, were identified (n = 766) and followed up to 22 yr or death. All new radiographic examinations related to musculoskeletal trauma with or without fracture were registered. Survival (mortality) and fracture was evaluated in 5-yr age bands and in age groups (<75, 75–84, and ≥85 yr). Mean age was 79.6 ± 9.9 yr (range, 31.6–99.4 yr), with 42% between 75 and 85 yr of age. Overall 22-yr survival was 6%: 79% at 1 yr, 48% at 5 yr, and 33% at 10 yr (i.e., population at risk). One-year mortality was 7%, 21%, and 33% for <75, 75–84, and ≥85 yr of age, respectively, and 95% of those ≥85 yr were dead at 10 yr. Prior hip fracture did not affect age-adjusted mortality (OR, 1.05; 95% CI, 0.756–1.20; p = 0.15). A total of 768 fractures were registered at 715 occasions in 342 women (45%; mean, 2.3 fractures/woman; range, 1–11 fractures/woman). Of the fracture occasions, 15% occurred within the first year, 27% within 2 yr, and 73% within 5 yr. The residual lifetime fracture risk was 45%, with a mortality-adjusted increase to 86%. The 10-yr fracture risk was 40%; with a mortality-adjusted increased to 65%. In conclusion, almost one half of all women with a hip fracture suffer a new fracture during their remaining lifetime. Fracture risk is highly dependent on age and survival, emphasizing that preventive strategies need to be tailored to each age group specifically.
A Bivariate Whole Genome Linkage Study Identified Genomic Regions Influencing Both BMD and Bone Structure
Authors: Liu Xiao-Gang , Liu Yong-Jun , Liu Jianfeng , Pei Yufang , Xiong Dong-Hai , Shen Hui , Deng Hong-Yi , Papasian Christopher J , Drees Betty M , Hamilton James J , Recker Robert R , Deng Hong-Wen
Published: July 2008

Areal BMD (aBMD) and areal bone size (ABS) are biologically correlated traits and are each important determinants of bone strength and risk of fractures. Studies showed that aBMD and ABS are genetically correlated, indicating that they may share some common genetic factors, which, however, are largely unknown. To study the genetic factors influencing both aBMD and ABS, bivariate whole genome linkage analyses were conducted for aBMD-ABS at the femoral neck (FN), lumbar spine (LS), and ultradistal (UD)-forearm in a large sample of 451 white pedigrees made up of 4498 individuals. We detected significant linkage on chromosome Xq27 (LOD = 4.89) for LS aBMD-ABS. In addition, we detected suggestive linkages at 20q11 (LOD = 3.65) and Xp11 (LOD = 2.96) for FN aBMD-ABS; at 12p11 (LOD = 3.39) and 17q21 (LOD = 2.94) for LS aBMD-ABS; and at 5q23 (LOD = 3.54), 7p15 (LOD = 3.45), Xq27 (LOD = 2.93), and 12p11 (LOD = 2.92) for UD-forearm aBMD-ABS. Subsequent discrimination analyses indicated that quantitative trait loci (QTLs) at 12p11 and 17q21 may have pleiotropic effects on aBMD and ABS. This study identified several genomic regions that may contain QTLs important for both aBMD and ABS. Further endeavors are necessary to follow these regions to eventually pinpoint the genetic variants affecting bone strength and risk of fractures.
Cooperative Regulation of Chondrocyte Differentiation by CCN2 and CCN3 Shown by a Comprehensive Analysis of the CCN Family Proteins in Cartilage
Authors: Kawaki Harumi , Kubota Satoshi , Suzuki Akiko , Lazar Noureddine , Yamada Tomohiro , Matsumura Tatsushi , Ohgawara Toshihiro , Maeda Takeyasu , Perbal Bernard , Lyons Karen M , Takigawa Masaharu
Published: July 2008

CCN2 is best known as a promoter of chondrocyte differentiation among the CCN family members, and its null mice display skeletal dysmorphisms. However, little is known concerning roles of the other CCN members in chondrocytes. Using both in vivo and in vitro approaches, we conducted a comparative analysis of CCN2-null and wildtype mice to study the roles of CCN2 and the other CCN proteins in cartilage development. Immunohistochemistry was used to evaluate the localization of CCN proteins and other chondrocyte-associated molecules in the two types of mice. Moreover, gene expression levels and the effects of exogenous CCN proteins on chondrocyte proliferation, differentiation, and the expression of chondrocyte-associated genes in their primary chondrocytes were evaluated. Ccn3 was dramatically upregulated in CCN2-null cartilage and chondrocytes. This upregulation was associated with diminished cell proliferation and delayed differentiation. Consistent with the in vivo findings, CCN2 deletion entirely retarded chondrocyte terminal differentiation and decreased the expression of several chondrocyte-associated genes in vitro, whereas Ccn3 expression drastically increased. In contrast, the addition of exogenous CCN2 promoted differentiation strongly and induced the expression of the associated genes, whereas decreasing the Ccn3 expression. These findings collectively indicate that CCN2 induces chondrocyte differentiation by regulating the expression of chondrocyte-associated genes but that these effects are counteracted by CCN3. The lack of CCN2 caused upregulation of CCN3 in CCN2-null mice, which resulted in the observed phenotypes, such as the resultant delay of terminal differentiation. The involvement of the PTHrP-Ihh loop in the regulation of CCN3 expression is also suggested.
Dezentrale Steuerung von Transportsystemen in Analogie zum Routing in Datennetzen (Decentralized Control of Transport Systems based on Data Routing Mechanisms)
Authors: Fay Alexander , Jerenz Stefan , Seitz Nando
Published: July 2008

Mit Hilfe dezentraler Steuerung kann in komplexen Transportsystemen auf kurzfristige Änderungen der Streckenbelastung schneller reagiert werden, als dies mit einem zentralen Planungs- und Optimierungsverfahren möglich ist. Der Beitrag beschreibt ein dezentrales Steuerungskonzept, welches sich an den Routing-Mechanismen von Datennetzen orientiert und diese für den Transport von physikalischen Gütern geeignet adaptiert.
Lounging on the Sofa with Leigh Hunt: A New Source for the Notes in Melville's Shakespeare Volume
Authors: Sanborn Geoffrey
Published: July 2008

The argument of this essay is that several of the notes that Herman Melville wrote in the back leaves of one of his Shakespeare volumes—notes that have been an object of interest and speculation ever since their discovery in the 1930s—were responses to essays written by Leigh Hunt and collected in a volume called The Indicator. In all likelihood, Melville read these essays—along with a Quarterly Review essay by Francis Palgrave, which has previously been shown to be the source of other notes in the back of the Shakespeare volume—on the sofa of his father-in-law, Lemuel Shaw, shortly before or after the birth of his son Malcolm in February 1849. The discovery of the new source is important both as an aid in identifying when and where Melville took all of these notes and as an indication of how carefully Melville studied the British periodical essay before beginning Moby-Dick (1851). In the essays of writers like Hunt, he encountered a form that seemed as though it could stretch to accommodate his literary and philosophical ambitions without sacrificing the companionship of the implied reader. For at least two years, Melville would believe enough in the possibilities of that form to compose his miraculously sociable expressions of unresolvable hope and rage, to give voice to the seemingly “wicked,” and yet to feel, as he told Nathaniel Hawthorne, “spotless as the lamb.”
The Place of a Servant in the Scale
Authors: Burrows Stuart
Published: July 2008

This essay examines the servants and shopkeepers who play a surprisingly central yet critically unacknowledged role in Henry James's fiction of the late 1890s, arguing that James's frequent depiction of lower-class life is a sign not of an unsuspected interest in class but of his familiar interest in consciousness. This interest has been memorably diagnosed by Sharon Cameron, who observes that in the work of James's last stage “consciousness is not in persons; it is rather between them”—that thoughts can be shared by characters without being spoken. Yet the writings that immediately precede James's last works offer a less reciprocal model of consciousness to the one that Cameron provides. Because the characters in What Maisie Knew (1897), The Awkward Age (1899), and The Turn of the Screw (1898) do not have access to the minds of those around them, they are forced to imagine other forms in which to measure both their own knowledge and that of others. The form they discover is the lives of the people who work for them. These subjects provide a fixed scale by which to measure the growth of consciousness in James's protagonists because they are assumed to have none of their own. Thus in The Turn of the Screw the terror experienced by the governess at the apparition of the ghosts of the former governess and valet can be understood as her realization that her identity is her situation; like them, she is reproducible, exchangeable, dispensable. The ghosts, that is, function as externalized figures for her own condition.
The decline of serum testosterone levels in community-dwelling men over 70 years of age: descriptive data and predictors of longitudinal changes
Authors: Lapauw B , Goemaere S , Zmierczak H , Van Pottelbergh I , Mahmoud A , Taes Y , De Bacquer D , Vansteelandt S , Kaufman J M
Published: July 2008

Objective

This study was designed to assess longitudinal changes in serum testosterone levels, explore relationships with aging, genetic-, health-, and lifestyle-related factors, and investigate predictors of changes in healthy elderly men.

Design

Population-based, longitudinal, 4-year observational study in 221 community-dwelling men aged 71–86 years at baseline.

Methods

Hormone levels assessed by immunoassay, anthropometry, questionnaires on general health, and genetic polymorphisms. Predictors of changes in testosterone levels explored using linear mixed-effects modeling for longitudinal analyses.

Results

Total testosterone (TT), free testosterone, and bioavailable testosterone (BioT) levels decreased with aging, decreases in BioT being most marked. No changes in sex hormone-binding globulin (SHBG) or estradiol (E2), while LH and FSH levels increased during follow-up. Subjects who gained weight displayed a greater decline in TT levels, mainly due to decreasing SHBG levels. However, baseline body composition was not predictive of subsequent changes in testosterone levels. Baseline E2 (P=0.023 to 0.004), LH (P=0.046 to 0.005), and FSH (P<0.002) levels were independently positively associated with a faster decline in testosterone fractions, although only FSH remained significant when adjusting for baseline testosterone (P=0.041–0.035). Carriers of a ‘TA’ haplotype of the estrogen receptor α gene (ERα) PvuII and XbaI polymorphisms displayed a slower decline of TT and BioT (P=0.041–0.007).

Conclusions

In elderly men with already low serum testosterone levels, a further decline was observed, independent of baseline age. The identification of FSH levels as a predictor of this decline appears to reflect the testicular mechanisms of aging-related changes in testosterone production, whereas associations with E2 and ERα polymorphisms are suggestive of estrogen-related processes, possibly related to changes in the neuroendocrine regulation of testosterone production.
Genetic variants in the USF1 gene are associated with low-density lipoprotein cholesterol levels and incident type 2 diabetes mellitus in women: results from the MONICA/KORA Augsburg case–cohort study, 1984–2002
Authors: Holzapfel C , Baumert J , Grallert H , Müller A M , Thorand B , Khuseyinova N , Herder C , Meisinger C , Hauner H , Wichmann H E , Koenig W , Illig T , Klopp N
Published: July 2008

Objective

Upstream transcription factor 1 (USF1) regulates genes of glucose and lipid metabolism. Polymorphisms in the USF1 gene showed association with familial combined hyperlipidemia and lipid parameters. The aim of our study was to examine the associations between USF1 polymorphisms and lipid parameters as well as incident type 2 diabetes mellitus (T2DM) in German Caucasians.

Design

We genotyped eight polymorphisms in the USF1 gene in 2067 middle-aged (35–74 years) individuals including 498 incident T2DM cases and 1569 non-cases of the population-based case–cohort study from the MONICA/KORA Augsburg project.

Methods

Six polymorphisms and their haplotypes were analyzed using multivariable linear regression and Cox proportional hazards models.

Results

Polymorphism rs3737787 was inversely associated with incident T2DM in women with decreased risk for female heterozygotes compared with women homozygous for the major allele (Hazard ratio=0.57; 95% confidence intervals: 0.38–0.87; P=0.008). After correction for multiple testing, significance remained. Polymorphisms rs3813609 and rs1556259 were significantly associated with reduction in low-density lipoprotein (LDL) cholesterol (pNOM=0.001; pNOM=0.00002) in women. Analyses also indicated associations of haplotypes with LDL cholesterol in women, but the association lost statistical significance after correction for multiple testing. Total serum cholesterol (TC) and high-density lipoprotein (HDL) cholesterol were weakly associated (P<0.05) with USF1 polymorphisms in women. No significant associations were found in men.

Conclusions

In this large population-based study, statistically significant associations of USF1 polymorphisms with incident T2DM and LDL cholesterol were found in women, but not in men. Genetic variants in the USF1 gene showed weak or no associations with TC and HDL cholesterol.
Behavior in Early Adolescence and Risk of Human Papillomavirus Infection as a Young Adult: Results From a Population-Based Study
Authors: Dempsey Amanda F. , Gebremariam Achamyeleh , Koutsky Laura , Manhart Lisa
Published: July 2008

OBJECTIVE. The goal of this study was to determine the utility of a risk factor-based approach to human papillomavirus catch-up vaccination.

METHODS. Data from waves I and III of the National Longitudinal Study of Adolescent Health were examined to determine the association between adolescent characteristics and future human papillomavirus infection. Analysis was restricted to 3181 female subjects who were >12 years of age when risk factors were assessed in wave I (1994–1995) and who underwent human papillomavirus testing as young adults in wave III (2001–2002). The main outcome of interest was a positive test result for ≥1 of 4 human papillomavirus types (human papillomavirus-6, -11, -16, or -18) targeted by the human papillomavirus vaccine currently available in the United States. Separate analyses were performed for sexually active and virginal adolescents. Poststratification sampling weights were used to generate nationally representative estimates.

RESULTS. Although nearly one half (43%) of the female adolescents were sexually active in wave I, adolescent sexual activity status was not associated with future detection of vaccine-specific human papillomavirus infection. Furthermore, for both virginal and sexually active adolescents, none of the assessed risk factors was associated with increased odds of future vaccine-specific human papillomavirus infection in multivariate models. Similar results were obtained when all high-risk human papillomavirus types were assessed as the outcome measure.

CONCLUSIONS. Behavioral risk factors assessed during adolescence are inadequate predictors of future infection with vaccine-type human papillomavirus. A risk factor-based approach to human papillomavirus catch-up vaccination is unlikely to be an effective implementation strategy.
Cerebral Blood Flow Velocity and Cognition in Children Before and After Adenotonsillectomy
Authors: Hogan Alexandra M. , Hill Catherine M. , Harrison Dawn , Kirkham Fenella J.
Published: July 2008

OBJECTIVE. The goal was to determine whether amelioration of sleep-disordered breathing through adenotonsillectomy would reduce middle cerebral artery velocity in parallel with improvements in cognition and behavior.

METHODS. For 19 children (mean age: 6 years) with mild sleep-disordered breathing, and 14 healthy, ethnically similar and age-similar, control subjects, parents repeated the Pediatric Sleep Questionnaire an average of 12 months after adenotonsillectomy. Children with sleep-disordered breathing underwent repeated overnight measurement of mean oxyhemoglobin saturation. Neurobehavioral tests that yielded significant group differences preoperatively were readministered. Middle cerebral artery velocity measurements were repeated with blinding to sleep study and neuropsychological results, and mixed-design analyses of variance were performed.

RESULTS. The median Pediatric Sleep Questionnaire score significantly improved postoperatively, and there was a significant increase in mean overnight oxyhemoglobin saturation. The middle cerebral artery velocity decreased in the sleep-disordered breathing group postoperatively, whereas control subjects showed a slight increase. A preoperative group difference was reduced by the postoperative assessment, which suggests normalization of middle cerebral artery velocity in those with sleep-disordered breathing. The increase in mean overnight oxyhemoglobin saturation postoperatively was associated with a reduction in middle cerebral artery velocity in a subgroup of children. A preoperative group difference in processing speed was reduced postoperatively. Similarly, a trend for a preoperative group difference in visual attention was reduced postoperatively. Executive function remained significantly worse for the children with sleep-disordered breathing, compared with control subjects, although mean postoperative scores were lower than preoperative scores.

CONCLUSIONS. Otherwise-healthy young children with apparently mild sleep-disordered breathing have potentially reversible cerebral hemodynamic and neurobehavioral changes.
Orientation transformation of Pb grains in 5Sn–95Pb/ 63Sn–37Pb composite flip-chip solder joints during electromigration test
Authors: Chiu Ying-Ta , Lin Kwang-Lung , Lai Yi-Shao
Published: July 2008

Microstructural evolution occurred in 5Sn–95Pb/63Sn–37Pb composite flip-chip solder bump during electromigration. Scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) observations for 5Sn–95Pb/63Sn–37Pb composite flip-chip solder joints subjected to 5 kA/cm2 current stressing at 150 °C revealed a gradual orientation transformation of Pb grains from random textures toward (101) grains. We proposed that the combination of reducing the surface energy of Pb grain boundaries and resistance of the entire polycrystalline system are the driving force for the orientation transformation of Pb grains during an electromigration test.
Nano body-centered cubic CoFe2alloy precursor for cobalt ferrite via sonoreduction process
Authors: Mohan Maya , Chandra Vimlesh , Manoharan S. Sundar
Published: July 2008

A stable nano body-centered cubic (bcc) CoFe2alloy was isolated by employing a combination of N2H4.H2O reduction and sonochemical route under basic conditions. This alloy has proved to be a potential precursor for CoFe2O4production. X-ray diffraction and transmission electron microscopy confirms the formation of a bcc phase CoFe2alloy with particle size <10 nm and spherical morphology. Thermogravimetric analysis confirmed the oxidation of the alloy composition showing a weight gain between 200 and 500 °C, which corresponds to fully oxidized CoFe2O4. A significant increase in the saturation magnetization (Ms= 230 emu/g) for the nano CoFe2alloy was observed in comparison with that of the theoretical bulk value (200 emu/g) at 300 K.
Raman and luminescence spectroscopy study of europium doped zirconia
Authors: Ovenstone James , Withnall Robert , Silver Jack
Published: July 2008

A Raman spectrometer was used to probe the structure and luminescence of a range of europium-doped zirconia phosphors prepared by different routes. We have demonstrated that the synthesis method and precursor type have a strong influence on the structure and luminescence of the final phosphor product. Raman spectroscopy has also demonstrated the presence of local order around the dopant ions that is not apparent in x-ray diffraction (XRD) and corresponds with changes in luminescence. As europium concentration is increased from 1 mol% to 20 mol%, the long range structure (from XRD) changes from tetragonal to cubic. Raman spectroscopy, however, shows that the 1 mol% material has a localized structure similar to the monoclinic undoped zirconia. This localized symmetry can explain the differences observed previously in emission spectra.
Generalized Periodontitis Associated With Chédiak‐Higashi Syndrome
Authors: Bailleul‐Forestier Isabelle , Monod‐Broca Jeanne , Benkerrou Malika , Mora Francis , Picard Bernard
Published: July 2008

Background:Chédiak‐Higashi syndrome (CHS) is a rare immunodeficient disorder. Patients with CHS are prone to severe periodontitis. To date, limited improvement following periodontal therapy has been reported. Thus, successful clinical outcomes in patients with CHS are of interest.

Methods:A 12‐year‐old girl was referred to the Department of Pediatric Dentistry, Hôtel‐Dieu/Garancière Hospital, for acute gingival inflammation and periodontal destruction. After a periodontal examination, the patient was sent to the Department of Medicine, Robert Debré Hospital, for a hematologic examination and was diagnosed with CHS. She has been receiving medical and dental treatments since that time. The medical treatment consisted of continuous, long‐term antibiotherapy. Supportive periodontal therapy was initiated with 4‐month recall periods. We report the diagnosis process and the 9‐year follow‐up.

Results:Radiographs and a periodontal examination showed deep probing pockets and extensive alveolar bone resorption. Hematologic and immunologic investigations showed normal values. Peripheral blood smears showed giant granules in neutrophils and leukocytes characteristic of CHS. Clinical improvement was observed after the initial periodontal therapy. No periodontitis recurrence was noted over a period of 9 years.

Conclusions:This case report shows that it is possible to treat periodontitis and maintain the periodontal health of a patient with a mild CHS phenotype over a long period. Patient compliance, regular dental follow‐ups, and long‐term systemic antibiotic treatments may be useful in stabilizing the periodontal condition of patients with CHS. Dentists must be aware that aggressive periodontitis, combined with general clinical signs, in young patients may reflect rare systemic disorders requiring biologic investigation.
P. gingivalis and E. coli Lipopolysaccharides Exhibit Different Systemic but Similar Local Induction of Inflammatory Markers
Authors: Liu Rongkun , Desta Tesfahun , Raptis Markos , Darveau Richard P. , Graves Dana T.
Published: July 2008

Background: Porphyromonas gingivalis is a Gram‐negative bacterium that is an important etiologic agent of human adult periodontitis. The goal of the study was to test the hypothesis that two isoforms of P. gingivalis lipopolysaccharide (PgLPS), PgLPS1435/1449 and PgLPS1690, exhibit differences in their capacity to stimulate systemic versus local responses compared to Escherichia coli lipopolysaccharide (LPS).

Methods: LPS was inoculated into the scalp of mice, and the response was measured locally at the site of inoculation and systemically in the heart/aorta. Vascular cell adhesion molecule (VCAM)‐1 was assessed at the protein level by enzyme‐linked immunosorbent assay, and VCAM‐1, E‐selectin, and intercellular adhesion molecule (ICAM)‐1 were assessed at the RNA level of the RNase protection assay. Serum tumor necrosis factor‐alpha (TNF‐α) levels were also measured.

Results: E. coli LPS and both isoforms of P. gingivalis LPS were relatively potent in stimulating the expression of inflammatory markers, with E. coli LPS being more potent. In contrast, when the systemic response was measured in the heart/aorta, E. coli LPS, but not P. gingivalis LPS, significantly induced inflammatory markers. At moderate to low doses (1 and 10 μg per injection), serum TNF‐α levels were minimally induced by P. gingivalis LPS compared to E. coli LPS.

Conclusions: Both forms of P. gingivalis LPS stimulated an inflammatory response when injected into connective tissue but were minimally stimulatory when a systemic response was measured. In contrast, E. coli LPS was a potent stimulus at the systemic and local levels.
The Effects of an Essential Oil and an Amine Fluoride/Stannous Fluoride Mouthrinse on Supragingival Plaque Regrowth
Authors: Pizzo Giuseppe , La Cara Monica , Licata Maria Ester , Pizzo Ignazio , D'Angelo Matteo
Published: July 2008

Background: The side effects of chlorhexidine (CHX) have stimulated the search for alternative antiplaque agents such as amine fluoride/stannous fluoride (ASF) and essential oils (EO). The aim of the study was to investigate the plaque‐inhibiting effects of two commercially available mouthrinses containing ASF and EO, respectively.

Methods: The study was an observer‐masked, randomized, 5 × 5 Latin square cross‐over design, balanced for carryover effects, involving 15 volunteers in a 4‐day plaque regrowth model. A 0.12% CHX rinse and a saline solution served as positive and negative controls, respectively. On day 1, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced rinsing with their allocated rinses. On day 5, subjects were scored for disclosed plaque. The ASF rinse was tested at two dosages: 10 and 20 ml (ASF‐10 and ASF‐20, respectively).

Results: The ASF and EO rinses showed a significant inhibition of plaque regrowth compared to saline (P <0.0001), but the lowest plaque indices were obtained with the CHX product (P <0.01). There were no significant differences among products containing ASF‐10, ASF‐20, and EO (P >0.05). There was no correlation between the occurrence of side effects and the use of a particular rinse product (P >0.2).

Conclusions: ASF and EO mouthrinses exerted effective and similar plaque inhibition. The two dosages tested for ASF did not differ in plaque reduction. These findings, together with those from long‐term trials, suggest that ASF and EO rinses may represent effective alternatives to CHX rinse as adjuncts to oral hygiene.
Clinical and Histologic Assessment of Lateral Alveolar Ridge Augmentation Using a Synthetic Long‐Term Bioabsorbable Membrane and an Allograft
Authors: Geurs Nicolaas C. , Korostoff Jonathan M. , Vassilopoulos Philip J. , Kang Tae‐Heon , Jeffcoat Marjorie , Kellar Robert , Reddy Michael S.
Published: July 2008

Background: Guided bone regeneration (GBR) is a widely used procedure for augmenting alveolar ridge width prior to placement of endosseous implants. Various graft materials and barrier membranes (non‐resorbable and bioabsorbable) have been used in GBR. The aim of this study was to assess the performance of a new bioabsorbable, synthetic polyglycolic acid/trimethylene carbonate (PGA/TMC) barrier membrane with an increased absorption time in conjunction with a combination of assayed demineralized bone matrix and cortical cancellous chips uniformly dispersed in a thermoplastic biologic carrier.

Methods: At 72 potential implant sites in 38 subjects, ridge width at the crest and 4 mm apical to the crest was measured before and 6 months after a GBR procedure using the long‐term (LT) PGA/TMC membrane and an allograft in a thermoplastic carrier. Before placement of endosseous implants, 48 biopsy specimens were obtained from the augmentation sites and analyzed histomorphometrically.

Results: The GBR procedure increased the mean ridge width at the crest from 2.4 to 5.2 mm. This 216% change from baseline was significant (P <0.001). The mean width 4 mm apical to the crest increased from 4.4 to 7.5 mm, a significant (P <0.001) 174% change. The histomorphometric analysis showed that the biopsy specimens consisted, on average, of 57% bone (36% graft material and 21% new bone) and 43% soft tissue and space.

Conclusion: Our findings suggest that the LT PGA/TMC barrier membrane, used in conjunction with an allograft, provides lateral alveolar ridge augmentation comparable to that achieved with other materials without the necessity for bone‐graft harvesting or a second procedure to remove the barrier membrane.
Short‐Term Clinical and Immunologic Effects of Scaling and Root Planing With Er:YAG Laser in Chronic Periodontitis
Authors: Lopes Beatriz M.V. , Marcantonio Rosemary Adriana C. , Thompson Gloria M.A. , Neves Lucia H.M. , Theodoro Letícia H.
Published: July 2008

Background: Recently, the erbium‐doped:yttrium, aluminum, and garnet (Er:YAG) laser has been used for periodontal therapy. This study compared Er:YAG laser irradiation (100 mJ/pulse, 10 Hz, 12.9 J/cm2) with or without conventional scaling and root planing (SRP) to SRP only for the treatment of periodontal pockets affected with chronic periodontitis.

Methods: Twenty‐one subjects with pockets from 5 to 9 mm in non‐adjacent sites were studied. In a split‐mouth design, each site was randomly allocated to a treatment group: SRP and laser (SRPL), laser only (L), SRP only (SRP), or no treatment (C). The plaque index (PI), gingival index (GI), bleeding on probing (BOP), and interleukin (IL)‐1β levels in crevicular fluid were evaluated at baseline and at 12 and 30 days postoperatively, whereas probing depth (PD), gingival recession (GR), and clinical attachment level (CAL) were evaluated at baseline and 30 days after treatment. A statistical analysis was conducted (P <0.05).

Results: Twelve days postoperatively, the PI decreased for SRPL and SRP groups (P <0.05); the GI increased for L, SRP, and C groups but decreased for the SRPL group (P <0.05); and BOP decreased for SRPL, L, and SRP groups (P <0.01). Thirty days postoperatively, BOP decreased for treated groups and was lower than the C group (P <0.05). PD decreased in treated groups (P <0.001), and differences were found between SRPL and C groups (P <0.05). CAL gain was significant only for the SRP group (P <0.01). GR increased for SRPL and L groups (P <0.05). No difference in IL‐1β was detected among groups and periods.

Conclusion: Er:YAG laser irradiation may be used as an adjunctive aid for the treatment of periodontal pockets, although a significant CAL gain was observed with SRP alone and not with laser treatment.
Implementation of the American Society of Anesthesiologists Physical Status Classification System in Periodontal Practice
Authors: Maloney William J. , Weinberg Mea A.
Published: July 2008

The American Society of Anesthesiologists Physical Status (ASA‐PS) classification is a preoperative rating given to each patient by an anesthesia provider with the sole purpose of assessing the physical state of the patient before anesthesia is administered. It was designed originally as a standardized way for dentists and physicians to convey information about the patient's overall health status and allow outcomes to be stratified by a global assessment of their severity of illness. However, in practice, the ASA‐PS classification is often misused as a measure of operative risk, which is the basis of much criticism. Modification of periodontal treatment may be necessary in certain medically complex patients. The ASA‐PS classification serves an integral part of risk assessment in determining how a patient should be managed by the periodontist. It should be incorporated into all periodontal practices. Medical assessment of patients has become an essential part of dentistry, as even the most common medical problems may require modifications to routine periodontal care. Periodontists must assess and manage patients for underlying medical conditions and are required to provide dental care to a diversity of medically complex patients. Today many patients in a periodontal practice have multiple medical conditions and are taking many medications. It is more difficult to manage these types of patients, and proper assessment of their physical status is an important part of clinical practice. The ASA‐PS classification system is a valuable assessment tool that subjectively categorizes patients into subgroups by preoperative physical fitness prior to administering anesthesia.
Shear-Type Borehole Wall Shifts Induced During Lost Circulations
Authors: Iwashita Daisuke , Morita Nobuo , Tominaga Masako
Published: July 2008

Borehole wall shifts during lost circulations are studied and parameter studies are conducted for evaluating the magnitude of the shifts under the following typical drilling conditions.

slant-crack induced around vertical wells during lost circulations borehole wall shifts induced during the drilling of normal, thrust, and strike-slip fault areas borehole wall shifts induced for an inclined well because of a fracture induced perpendicular to the minimum in-situ stress

Parameters varied are the frac size/wellbore size, frac angle, borehole pressure, and σh1,σH2,σv ratio. These analyses are significant for the following reasons:

A new fracture model from a borehole is coded using a 3D-dual-boundary element method. This method allows different displacement and stress traction at the two fracture surfaces along a fracture plane around a borehole. Note that other boundary element methods for 3D nonplanar hydraulic fracture problems have been developed by another group, but these methods did not include a borehole (Yamamoto et al. 1999). Minor borehole wall shifts occur with small-scale fluid losses as observed with borehole imagers (Maury and Zurdo 1996). Although these minor shifts do not create drilling problems, the in-situ stresses may be evaluated from the borehole wall shift if the fractured area is identified by acoustic devices. The current model quantifies the relation between these shifts and other parameters (such as the geological properties and frac size and angle). Significant borehole wall shifts occur if a lost circulation is significant and the leakoff plane is inclined with respect to the principal in-situ stress direction. Some stuck pipe problems may be caused by shear type borehole wall shifts rather than by borehole breakouts or differential sticking problems.
Guidelines for Shale Inhibition During Openhole Gravel Packing with Water-Based Fluids
Authors: Shenoy S. , Gilmore T. , Twynam A. J. , Patel A. , Mason S. , Kubala G. , Vidick B. , Parlar M.
Published: July 2008

Many of the problems associated with the use of water-based fluids in drilling and completion operations are caused by incompatibilities between the fluids and the shales. Such incompatibilities may result in washouts, increased drilling costs (e.g., solids handling, rig time, dilution fluids), and shale sloughing during the drilling operation and after displacements to completion fluids or during gravel packing. One of the most important factors leading to an undesired result (either a premature screenout, thus a potential sand-control failure, or a higher skin) in water-packing of open holes is the presence of reactive shales in the interval to be gravel packed.

Although there is a substantial amount of literature on shale inhibition with water-based drilling fluids, the importance of shale inhibition and the problems associated with shale reactivity during gravel packing remain largely unexplored. Furthermore, shale-inhibitor selection often relies on a comparison of the results from bottle-roll tests using shale samples in candidate fluid/inhibitor pairs (drilling or completion fluid) and on tests measuring the degree of shale swelling. While these tests are highly functional, they can provide information only on the relative performance of fluids, and their relevance to gravel packing is questionable because these tests do not simulate the conditions experienced during such treatments.

This paper presents guidelines on selection methodology of shale inhibitors for use in gravel-packing applications on the basis of the data available in our respective companies, including a comparison of results from conventional bottle-roll tests to those from flow through predrilled holes in shale core samples. Recommendations are made depending on brine type and density, type of shale, temperature, fluid exposure history, and environmental considerations.
Ultradeep Drilling Pushes Drillstring Technology Innovations
Authors: Jellison Michael J. , Chandler R. Brett , Payne Mike L. , Shepard Jeff S.
Published: July 2008

Drilling ultradeep (UD) wells places significant requirements on the drillstring. Lengthy drillstrings lead to high tensile loads, which can lead to slip crushing of the drillstring; hoisting capacity issues; and drillpipe collapse capacity concerns at the blowout preventer (BOP). BOP shear rams may also have difficulty shearing today's high-strength, high-toughness drillpipe. Bottomhole assembly (BHA) connection failures pose greater risk and cost at UD well depths.

This paper analyzes the many challenges associated with drill-string designs specifically for UD drilling (UDD). It presents emerging drillstring technologies that are solutions expected to increase depth capability for the industry's continued advancement of deep-drilling operations.
Underbalanced Drilling of a Horizontal Well in Depleted Reservoir: A Wellbore-Stability Perspective
Authors: Qiu Kaibin , Gherryo Yousef , Tan Chee Phuat , Marsden Rob
Published: July 2008

The need to reduce formation damage and to avoid differential sticking and lost circulation in depleted reservoirs favors the use of underbalanced-drilling (UBD) technology. In highly depleted reservoirs, the pore pressure can be very low, necessitating the use of extremely low-density fluid to achieve an equivalent circulating density (ECD) below the pore pressure. In such situations, the stress redistribution around the wellbore has to be supported mainly by the rock matrix, and limited support that is provided by the mud pressure. Therefore, UBD can dramatically increase the risk of wellbore instability.

From literature review, it was found that the techniques and methodologies to carry out wellbore-stability analysis on UBD of horizontal wells are not well documented. This paper presents a wellbore-stability study that was conducted to evaluate the feasibility of using UBD technology to drill a horizontal well in a highly depleted reservoir in Libya.

The study started with geomechanical laboratory tests and mechanical Earth Model (MEM) construction to evaluate the in-situ stresses, pore pressure, and mechanical properties of the formations likely to be encountered during the planned UBD campaign.

Wellbore-stability analysis was subsequently conducted for the planned horizontal well to be drilled underbalanced using a new practical approach. The analysis revealed a high probability of extensive and severe breakout within the weak zones if penetrated underbalanced and the potential for massive wellbore collapse. Under the guidance of this study, the well plan and drilling designs were amended to minimize drilling risk.
Best Practice in Understanding and Managing Lost Circulation Challenges
Authors: Wang Hong (Max) , Sweatman Ronald , Engelman Bob , Deeg Wolfgang , Whitfill Don , Soliman Mohamed , Towler Brian F.
Published: July 2008

Lost circulation has been one of the major challenges that cause much nonproductive rig time each year. With recent advances, curing lost circulation has migrated from "plugging a hole" to "borehole strengthening" that involves more rock mechanics and engineering. These advances have improved the industry's understanding of mechanisms that can eventually be translated into better solutions and higher success rates. This paper provides a review of the current status of the approaches and a further understanding on some controversial points.

There are two general approaches to lost circulation solutions: proactive and corrective, based on whether lost circulation has occurred or not at the time of the application. This paper provides a review of both approaches and discusses the pros and cons related to different methods—from an understanding of rock mechanics and operational challenges.
The Potential for Crop‐to‐Wild Gene Flow in Sorghum in Ethiopia and Niger: A Geographic Survey
Authors: Tesso Tesfaye , Kapran Issoufou , Grenier Cécile , Snow Allison , Sweeney Patricia , Pedersen Jeff , Marx David , Bothma Gurling , Ejeta Gebisa
Published: July 2008

Information about the potential for crop–wild hybridization is needed to understand how crop genes, including transgenes, affect the population genetics and ecology of sexually compatible relatives. Transgenic sorghum is under development for use by traditional farmers in Africa, the center of origin for sorghum [Sorghum bicolor (L.) Moench], but systematic surveys of the current extent of contact with wild and weedy relatives are lacking. We studied wild and weedy sorghums that are interfertile with the crop and constitute a crop–wild–weed complex. The survey was conducted in 2005 in areas of traditional sorghum cultivation in three regions of Ethiopia and two regions of Niger. Within each region, we examined eight representative sorghum fields at each of 10 locations during peak flowering of the crop. In all regions, wild and weedy sorghum occurred intermixed with and adjacent to cultivated sorghum. Wild and weedy sorghums were detected at 56, 44, and 13% of the Ethiopian sites (Amhara, Tigray, and Hararghe regions, respectively), and 74 and 63% of sites in Niger (Maradi‐Tahoua and Tillabery‐Dosso regions, respectively). Flowering periods of wild and weedy sorghum populations overlapped with those of cultivated sorghum at most sites where the two co‐occurred, especially in Ethiopia, and many putative crop–wild hybrids were observed. Therefore, current gene transfer from cultivated sorghum to wild and weedy sorghum populations in Ethiopia and Niger is likely to be widespread.
Novel Germplasm Resources for Improving Environmental Stress Tolerance of Hexaploid Wheat
Authors: Trethowan R. M. , Mujeeb‐Kazi A.
Published: July 2008

Wheat (Triticum spp. L.) breeders have significantly improved wheat adaptation to stress‐prone environments around the world. This progress has largely been achieved using empirical selection and genetic variability within the primary wheat gene pool. As most stress tolerance traits are quantitatively inherited, expansion of the available genetic diversity for stress tolerance is necessary if rates of genetic progress are to be maintained. This review explores three sources of novel genetic variability, namely synthetic wheat, landrace cultivars, and alien introgressions and their applicability to applied wheat breeding. Synthetic hexaploid wheat, derived by crossing tetraploid wheat with Aegilops tauschii, provides new genetic variability for adaptation to drought, high temperature, salinity, waterlogging, and soil micronutrient imbalances from the secondary wheat gene pool. Synthetic‐derived materials have performed well in many stressed environments globally. There is significant unexploited variation among landraces and modern wheat cultivars to improve the stress adaptation of cultivated wheat. The tertiary gene pool, with a few significant exceptions, has been more difficult to exploit due to complex inheritance, meiotic instability, and linked deleterious effects. Nevertheless, there is sufficient genetic variation in the wheat gene pool to ensure the continued improvement of wheat adaptation to abiotic stress.