bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitric Oxide Synthase Inhibition Prevents Alveolar Bone Resorption in Experimental Periodontitis in Rats
Authors: Leitão R.F.C. , Ribeiro R.A. , Chaves H.V. , Rocha F.A.C. , Lima V. , Brito G.A.C. 
Published: June 2005

Background: Periodontitis is the most frequent cause of tooth loss in adults. Nitric oxide (NO) has been linked to bone resorption mechanisms during inflammation processes. The aim of this study was to investigate the effect of NOS (NO synthase) inhibitors in the alveolar bone loss in an experimental periodontitis disease (EPD) model.Methods: Wistar rats were subjected to a ligature placement around the second upper left molars and were sacrificed at 11 days. Alveolar bone loss was evaluated by the sum of distances between the cusp tips and the alveolar bone along the axis of each molar root, subtracting from the contralateral side. Histopathological analysis was based on cell influx, alveolar bone, and cementum integrity. Leukogram was performed at 6 hours and 1, 7, and 11 days after the EPD induction. Groups were treated with the NOS inhibitors, aminoguanidine (AG) (2.5 to 10 mg/kg/d), or L‐arginine methyl ester (L‐NAME, 5 to 20 mg/ kg/d) intraperitoneally (i.p.), 1 hour before the EPD induction and daily for 11 days. Controls received only saline (EPD group). As controls for L‐NAME specificity, groups were co‐treated with either L‐arginine (150 to 600 mg/kg/d) or D‐arginine (600 mg/ kg/d) and L‐NAME (20 mg/kg/d). Different groups were used for morphometric and histopathological analysis.Results: Both L‐NAME and AG significantly and dose‐dependently inhibited the alveolar bone loss as compared to EPD group. L‐NAME (20 mg/kg/d) reduced the alveolar bone loss by 50%, whereas AG (5 mg/kg/d) reduced it by 47% compared to EPD. This result was coupled to a significant reduction of cell influx to the periodontium, as well as to the preservation of alveolar bone and cementum, seen at histopathology, for both compounds. The co‐administration of L‐arginine, but not of D‐arginine reversed L‐NAME effects.Conclusion: These data provide evidence that NOS inhibitors prevent inflammatory bone resorption in experimental periodontitis. J Periodontol 2005;76:956‐963.
Effect of Neutrophil Apoptosis on Monocytic Cytokine Response to Porphyromonas gingivalis Lipopolysaccharide
Authors: Berker Ezel , Kantarci Alpdogan , Hasturk Hatice , Van Dyke Thomas E. 
Published: June 2005

Background: Neutrophil apoptosis may play a critical role in the resolution of inflammation by stimulating anti‐inflammatory cytokine generation from monocytes. In this study, we investigated the effect of apoptotic neutrophils on interleukin (IL)‐10 and IL‐1β production from monocytes in response to Porphyromonas gingivalis lipopolysaccharide.Methods: Peripheral blood neutrophils from healthy individuals were isolated by sodium diatrizoate density gradient centrifugation. In order to induce apoptosis, neutrophils were cultured for 24 hours in modified Dulbecco's medium supplemented with 10% autologous serum. Cell apoptosis was quantified by Annexin V positivity and loss of CD16 expression on the cell surface. Peripheral blood mononuclear cells were isolated from the same subjects; monocytes were purified by magnetic cell sorting and cultured with or without apoptotic or fresh neutrophils. Lipopolysaccharide from Porphyromonas gingivalis was used for cell stimulation. IL‐1β and IL‐10 levels in supernatants were determined by enzyme‐linked immunosorbent assay (ELISA).Results: IL‐10 generation was significantly increased in monocytes cultured with apoptotic neutrophils compared to monocytes alone or cocultured with fresh neutrophils (P <0.05). IL‐1β was suppressed both in resting and lipopolysaccharide‐stimulated monocytes in the presence of apoptotic neutrophils compared to monocytes alone or monocytes cultured with fresh neutrophils at all time points (P <0.05).Conclusion: Neutrophil apoptosis provides a signal to monocytes, changing the phenotype of the monocyte resulting in the production of anti‐inflammatory cytokines and suppression of proinflammatory cytokines in response to lipopolysaccharide. J Periodontol 2005;76:964‐971.
Outer Membrane Vesicles From Porphyromonas gingivalis Affect the Growth and Function of Cultured Human Gingival Fibroblasts and Umbilical Vein Endothelial Cells
Authors: Bartruff Jeffrey B. , Yukna Raymond A. , Layman Don L. 
Published: June 2005

Background: The purpose of this study was to examine the effects of outer membrane vesicles (OMV) obtained from Porphyromonas gingivalis (Pg) on the growth and function of human gingival fibroblasts (HGF) and human umbilical vein endothelial cells (HUVEC).Methods: OMV were obtained from a cell‐free growth medium of Pg ATCC 33277 by 40% NH2SO4 precipitation and ultracentrifugation. Cell proliferation was measured by 3H‐thymidine incorporation into growing HGF and HUVEC. Endothelial cell function was determined by their capacity to form a network of capillary tubes on an extracellular matrix (ECM).Results: Proliferating HGF and HUVEC demonstrated a significant dose‐dependent inhibition of 3H‐thymidine uptake when cultured with 0 to 40 µg/ml of OMV protein. HGF and HUVEC showed an IC50 of growth of about 9.0 µg/ml and 4.5 µg/ml of OMV protein, respectively. Capillary tube formation by HUVEC cultured on an ECM was suppressed by 70% to 80% with 5 µg/ml OMV protein after 18 hours of incubation. The presence of proteolytic enzymes in the OMV did not contribute to capillary tube disruption, since blocking enzyme activity with specific inhibitors did not reduce the suppression of capillary tube formation. After heating at 90°C for 5 minutes, OMV significantly lost their capacity to suppress capillary tube formation.Conclusions: OMV significantly inhibit the proliferation of cultured HGF and HUVEC in a dose‐dependent manner. OMV suppressed the capillary tube formation by cultured HUVEC. The factor(s) appeared to be a protein and not endotoxin because its inhibitory activity was markedly reduced by heat inactivation. These studies suggest that OMV contribute to chronic periodontitis by suppressing cell proliferation and revascularization in periodontal tissues. J Periodontol 2005;76:972‐979.
Pain Experienced by Patients During Periodontal Recall Examination Using Thinner Versus Thicker Probes
Authors: Hassan Mohamed A. , Bogle Gary , Quishenbery Mary , Stephens Denise , Riggs Matt , Egelberg Jan 
Published: June 2005

Background: The aim of the present study, performed during periodontal recall visits, was to compare the levels of pain experienced by patients during periodontal probing using probes with tip diameters of either 0.40 mm or 0.63 mm.Methods: Three groups of 20 adult patients were examined by three different therapists. Diagonal maxillary/mandibular quadrants were probed with a 0.40 mm and a 0.63 mm probe, respectively. At the completion of probing of each quadrant, the patients were asked to describe their pain using a visual analog scale (VAS).Results: Most patients showed low VAS pain scores for both probes. However, using an arbitrary threshold of VAS ≥40 mm to indicate significant pain, some patients had a painful experience. Lower median pain responses following probing with the 0.63 mm probe compared to the 0.40 mm probe were observed for patients of therapist 1, and for the quartile of all 60 patients that showed the highest VAS scores. For therapist 2 and 3 groups, no differences were found. The pain levels expressed by the three groups of patients varied, confirming results of our previous studies, which also observed differences in patients' pain experiences following probing by different therapists.Conclusions: The ability to deliver dental care with a minimum of patient discomfort would seem to be an essential part of the skills of individual clinicians. We would like to suggest that dental therapists periodically evaluate this part of their skill by asking patients to express their pain experiences following various procedures using VAS scales. J Periodontol 2005;76:980‐984.
Effect of Topical Cimetidine Rinse on Gingival Crevicular Neutrophil Leukocyte Function
Authors: Van Dyke Thomas E. , Cutler Christopher W. , Kowolik Michael , Singer Robert S. , Buchanan William , Biesbrock Aaron R. 
Published: June 2005

Background: Three coordinated mechanism‐of‐action clinical studies were conducted to examine the effects of topical cimetidine rinse on neutrophil function in the gingival crevice.Methods: The first study was a randomized, double‐blind, placebo‐controlled, 28‐day experimental gingivitis study involving 21 healthy adults, in which subjects rinsed twice a day with placebo or 0.5% cimetidine rinses. At baseline and days 14, 21, and 28, neutrophils were harvested from prespecified gingival sulcular sites, purified, stained, and examined by trifluorochrome phagocytosis and killing microassay. The second and third studies were placebo‐controlled, 9‐week, three‐period (each of 3 weeks’ duration), longitudinal studies involving seven and nine adults with moderate periodontitis, respectively. Subjects rinsed twice a day during periods 1 and 3 with placebo and during period 2 with 0.5% cimetidine. At baseline and weekly intervals, neutrophils were harvested from prespecified periodontal pockets, purified, stained, and examined by trifluorochrome phagocytosis and killing microassay in the second study. In the third study, neutrophils were examined spectrophotometrically for superoxide production and in a luminol‐enhanced chemiluminescence assay.Results: In the first study, the mean number of phagocytosing neutrophils was statistically significantly increased (P = 0.016) in the cimetidine group (31.1 cells/subject) versus the placebo group (13.7 cells/subject) at day 28. In addition, a statistically significant increase (P = 0.036) in bacterial killing was observed in the cimetidine rinse group; in the cimetidine group, 63.4% of bacteria in the neutrophils were killed compared to 46.2% in the placebo group. Additional data from the other two studies support these findings.Conclusion: Collectively, these studies provide evidence that topical 0.5% cimetidine oral rinse enhances the antibacterial function of crevicular neutrophils. J Periodontol 2005;76:998‐1005.
An equation‐of‐state contribution for polar components: Quadrupolar molecules
Authors: Gross Joachim 
Published: June 2005

AbstractAn equation‐of‐state (EOS) contribution for quadrupolar interactions is developed based on a third‐order perturbation theory. Model constants are adjusted to comprehensive molecular simulation data for vapor–liquid equilibria of the two‐center Lennard–Jones (2CLJ) plus pointquadrupole fluid from the literature. Molecular elongations L* from 0 (spherical) to 0.8 are covered by the simulation data. The EOS is suited for both, the 2CLJ fluid and the tangent‐sphere Lennard–Jones framework. It is applied to pure components and mixtures of real substances with the perturbed‐chain statistical associating fluid theory (PC‐SAFT) EOS. It is possible to use tabulated values of quadrupolar moments (independently determined) directly in the EOS, so that no additional pure component parameter is introduced. Compared with the case where quadrupolar interactions are not specifically accounted for, the proposed model gives a systematic improvement of pure component properties and of mixture phase equilibria of strong quadrupolar components, such as carbon dioxide, and the absolute value of the required binary interaction parameter is significantly reduced. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Magnetic resonance imaging velocimetry of fluid flow in a clinical blood filter
Authors: Heese Frank , Robson Philip , Hall Laurie 
Published: June 2005

AbstractMultislice spin echo (SE) pulsed‐field gradient phase‐contrast (PFG‐PC) magnetic resonance imaging (MRI) velocimetry has been used to determine the complex three‐dimensional (3‐D) recirculatory flow pattern of a simple, single‐phase blood analogue fluid (glycerol–water solution 70–30 vol%) in a commercially available blood filter (PALL AL8 arterial line blood filter), whose inlet and outlet ports are about 0.95 cm in diameter. The maximum shear stress measured in the fluid is 10 Pa, which is significantly lower than the value for the onset of red blood cell hemolysis. The flow field is in agreement with computational flow modeling (Fluent 4.3) and is reminiscent of the hydrocyclone flow in industrial separation devices. The development of this flow pattern is demonstrated for three different volume flow rates (1, 2, and 3 L/min). © 2005 American Institute of Chemical Engineers AIChE J, 2005
Raymond Pearl memorial lecture, 1989: Cultural practices as determinants of clinical pathology and epidemiology of venereal infections: Implications for predictions about the AIDS epidemic
Authors: Gajdusek D. Carleton 
Published: June 2005

AbstractSexually transmitted diseases newly introduced into diverse primitive and isolated populations have behaved differently in clinical severity and seriousness of the epidemics they have caused, because of culturally different sexual practices. Epidemic interstitial plasma cell pneumonia in the 1930s–1950s in eastern and northern Europe, caused by Pneumocystis carinii and accompanied by cytomegalovirus infection, was an unexpected AIDS‐like epidemic which spread slowly, then quickly and inexplicably disappeared. Newly recognized endemic HTLV‐I and epidemic HIV human retrovirus infections are behaving in a fashion similarly difficult to anticipate and predict.
Preterm infants born to women who had an elevated prepregnancy body mass index appear to be at increased risk of germinal matrix hemorrhage
Authors: Leviton Alan , Pagano Marcello , Kuban Karl C. K. , Fenton Terence , Wolff Mildred , Strassfeld Ruth 
Published: June 2005

AbstractIn a sample of 449 infants of birthweight ≤ 1.5 kg, the risk of germinal matrix hemorrhage increased monotonically with increases in maternal body mass index (BMI, wt/ht2). This relationship was repeated in many strata of the sample, including those defined by the occurrence of labor, maternal preeclampsia, route of delivery, intubation of the baby and acidosis, as well as strata defined by birthweight and gestational age. Even though the dose‐response relationship is prominent, caution is advised in drawing inferences from these findings until confirmation is provided that preterm infants born to mothers of high BMI are at increased risk of germinal matrix hemorrhage. © 1992 Wiley‐Liss, Inc.
Linked loci in chromosome 1 (FXIIIB, HF, PEPC) and their variability in Brazilian Indians
Authors: Kömpf J. , Luckenbach Ch. , Krczal D. , Salzano F. M. , Callegari‐Jacques S. M. 
Published: June 2005

AbstractA total of 352 individuals living in seven localities of two Brazilian Indian groups (Macushi and Içana River Indians) were variously studied for coagulation factor XIIIB, human factor H, and a new polymorphism of peptidase C. No significant inter‐ or intra‐tribal differences were found for the FXIIIB alleles, the frequencies varying around 95% for F13B*3 and 5% for F13B*1. Results for HF were heterogeneous, HF*A presenting a much higher frequency among the Macushi (32%) than among the Içana River Indians (9%). Intratribal differences were also found among both groups. Linkage disequilibrium exists between alleles of these two systems (0.03 ± 0.01). These are the first results for human factor H obtained among Amerindians. The data for PEPC were limited to the Içana River Indians. There is heterogeneity among the three localities sampled and evidence of moderate linkage disequilibrium between markers in this locus and in F13B (0.02 ± 0.01). © 1992 Wiley‐Liss, Inc.
Sexual behavior and Down syndrome: The biological mechanism
Authors: Martin‐DeLeon Patricia A. , Williams Mary B. , Reynolds James F. 
Published: June 2005

AbstractSufficient evidence of a correlation between infrequent coitus and Down syndrome (DS) has now accumulated to warrant reevaluation of the suggested biological mechanisms. The evidence provides no support for delayed fertilization as the mechanism responsible for this correlation, as was originally proposed by German [Nature 217:516–519, 1968]. A better explanation of this association is provided by the sperm aging hypothesis, which gains its support from both animal studies and chromosomal findings of a paternal contribution to DS. The animal studies supporting this hypothesis show an increased incidence of sperm‐derived trisomies resulting from sperm stored for prolonged periods in the male tract. The chromosomal findings show a paternal origin in 20% of DS infants; the sperm aging hypothesis concerns the biological mechanism in this 20%. In addition to explaining the excess of DS for older mothers, the sperm aging hypothesis explains the excess for teenaged unwed mothers and indicates that sperm aging from decreased ejaculatory frequency may be a cause of DS in all age groups. Testable directly in humans against German's delayed fertilization hypothesis, the sperm aging hypothesis has immediate clinical implications. It suggests (1) an approach to reduce the incidence of DS and miscarriages and (2) clinical research that will increase knowledge of the circumstances indicating a need for antenatal monitoring.
The bingo model IV. The statistics of survivorship in the bingo‐gamma model
Authors: Murphy Edmond A. , Trojak Joseph E. , Berger Kenneth R. , Foster Ella C. , Opitz John M. 
Published: June 2005

AbstractThe survivorship (time to death or failure) of a bingo‐gamma (BG) model is defined as the minimum among the waiting times for completion among k independent gamma processes. The ith process is of order ni, with a mean rate for the occurrence of hits of ai, In this paper we address the case where, for all competing processes, the order and the rate at which hits occur are the same but both they and k are unknown. We denote by k the multiplicity, by n the order or the number of hits to failure, and by a the transition parameter. The joint maximum likelihood estimator (MLE) of the three paramters of this BG process is developed. An algorithm for calculating it has been devised and a computer program in BASIC has been written. The properties of the MLE: have been explored systematically, mainly by Monte Carlo simulation. The distributions, means, variances, covariances, and correlation coefficients of the three parameters are explored for samples of size 25 and samples of size 100. Also, the simple average of the observed survival times (which gives a method of moments estimator of the mean survival) is compared with the MLE of the mean survival; the two estimators seem to be unbiased and about equally efficient.
The bingo model of survivorship V. The problems of conformation to the empirical evidence
Authors: Murphy Edmond A. , Berger Kenneth R. , Trojak Joseph E. , Pyeritz Reed E. , Opitz John M. 
Published: June 2005

AbstractWe discuss the statistical and biological problems of adapting the theoretical bingo model to the analysis of empirical data. A distinction is made between an idealized pathogenetic model, which aims to represent the disease in as much authentic detail as the present state of knowledge allows and in components that have literal interpretation, and an empirical model, which deals with those effects of the pathogenetic model that one may hope to observe clinically. We review a variety of empirical models distinguishable by the amount of data available on intermediate degrees of damage short of total destruction. The relationship of damage to time is explored, and we consider the criteria and usefulness of linearization of this relationship where the diachronic (“longitudinal”) data are few and extend over a comparatively short time. Every time a patient is examined, the degree of cumulative damage is assessed in each of the body systems of interest. Thus the examination will furnish a set of measurements, which is obtained on each of several examinations, taken over a period that for preference is long relative to the survival of the system. Specific disorders discussed include dentition and enlargement of the aorta with age in the Marfan syndrome.
Unique mosaicism in Prader‐Labhart‐Willi syndrome—a contiguous gene or aneuploidy syndrome?
Authors: Kousseff BG , Diamond T , Essig Y , Miller K , Tedesco T , Opitz John M. , Reynolds James F. , Ledbetter David H. 
Published: June 2005

AbstractA 16‐year‐old boy with Prader‐Labhart‐Wi11i syndrome (PLWS) had hypotonia, feeding difficulties, failure to thrive, strabismus and bilateral inguinal hernias with cryptorchidism during infancy followed by hyperphagia, marked early‐onset obesity with insulin‐dependent diabetes mellitus and necrobiosis lipoidica diabeticorum, short stature, hypogonadotropic hypogonadism and some of the facial characteristics of the individuals with the PLWS. IQ is estimated around 90.Cytogenetic studies showed mosaicism: 45,X, t(Y;15) with partial deletion 15 (15pter → 15ql2); 46,X, t(Y;15), dic(15)(15pter → 15ql2::15ql2 → 15pter) and 47,X,t(Y;15), dic(15), dic(15). The dic(15) was bisatel1ited, NOR‐positive on both arms and represented inv dup(15). Thus, the 2 lines with the dic(15) showed partial trisomy 15 (15pter → 15q 12) and partial pentasomy 15 (15pter → 15ql2), respectively. The cell line ratios were different in lymphocyte and fibroblast cultures.The unique cytogenetic findings in this patient, the reports of a variety of chromosome 15 aberrations in PLWS; as well as aberrations of other chromosomes, suggest that the condition is a contiguous gene syndrome rather than an aneuploidy syndrome.
Penetrance in the presence of genetic susceptibility to environmental factors
Authors: Khoury Muin J. , Flanders W. Dana , Beaty Terri H. , Optiz John M. , Reynolds James F. 
Published: June 2005

AbstractMany single‐gene disorders (especially dominant traits) are known to exhibit “incomplete penetrance,” a term often criticized as reflecting our ignorance of genetic and environmental factors that may interact with the genotype to determine the ultimate phenotype of the individual. We explore the effects of an environmental factor on penetrance for a simple model of single gene‐mediated susceptibility to environmental factors. We show that penetrance of the susceptible genotype increases with increasing frequency of exposure to the factor and the strength of interaction between the factor and the genotype (relative risk). For disorders with disease frequency of 0.001 or less (as seen with many congenital malformations), penetrance is generally low (<10%) if the exposure frequency is low (<10%) even in the face of strong gene‐environment interaction. Such low penetrance can lead to low recurrence risks. Single‐gene effects could easily be overlooked in genetic analysis unless specific environmental factors are considered.
Prenatal diagnosis of the fragile X – The Australasian experience
Authors: Purvis‐Smith Stuart G. , Laing Sue , Sutherland Grant R. , Baker Elizabeth 
Published: June 2005

AbstractIdentification of increasing numbers of females heterozygous for fragile X linked mental retardation together with improved genetic counselling is creating a growing demand for prenatal diagnosis of fra(X). However, present cytogenetic techniques are somewhat unreliable and our collaborative approach has endeavoured to improve quality of cell culture systems and the sensitivity of fra(X) detection.Since 1985 we have exchanged cell cultures between our laboratories for verification of diagnostic results and comparison of induction techniques and have benefitted from larger numbers of cells scored for fra(X). Our 50 cases represent almost all of such studies undertaken in Australasia (Australia and New Zealand). Ten cases were unequivocally fra(X) positive; there was discrepancy between laboratories in 4 cases and one false‐negative case.We propose a protocol to enhance fra(X) detection and conclude that, provided care is exercised, couples at risk of a fra(X) pregnancy can benefit from prenatal cytogenetic diagnosis.