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921.
Attachment, growth and synthesis by human gingival fibroblasts on demineralized or fibronectin-treated normal and diseased tooth roots 总被引:2,自引:0,他引:2
Regeneration of a fibrous attachment to tooth roots previously exposed to periodontal pockets requires interaction between the root surface and fibroblasts. Experiments were designed to assess whether or not fibroblasts will attach, grow and synthesize normally on tooth roots and determine the efficacy of various treatments of diseased root surfaces on these activities. Extracted teeth were collected, washed and stored frozen until used. The roots were sectioned and the surface area determined. All roots were thoroughly planed to remove most of the cementum and some were then treated with fibronectin or citric acid. Each root was placed in a Linbro well and a suspension of fibroblasts in Dulbecco Vogt medium with 10% fetal calf serum added. After cell attachment, each root was transferred to a fresh well and incubated. Some roots were examined by scanning electron microscopy. Attachment and growth were assessed by harvesting and counting cells after various incubation times. The pattern of protein synthesis was determined by preparing fluorographs from cultures pulse labeled with radioactive S35-methionine. Cells attach and grow on planed root surfaces. The number that attach to normal and diseased roots is greatly enhanced by pretreatment with fibronectin or citric acid. By day three, the cells become confluent at approximately 20,000/cm2. The pattern of proteins produced is comparable to that seen in cultures maintained in petri dishes. After root planing, cells attach, grow and synthesize equally well on diseased and normal roots. 相似文献
922.
Blastogenic responsiveness of peripheral blood mononuclear cells from individuals with various forms of periodontitis and effects of treatment 总被引:2,自引:0,他引:2
Stig K. Osterberg Roy C. Page Tom Sims Greggory Wilde 《Journal of clinical periodontology》1983,10(1):72-88
Abstract Experiments were done to learn whether or not the blastogenic responsiveness of peripheral blood mononuclear cells (PBM) from 34 patients to mitogens and homogenates of a panel of periodontal bacteria differs significantly from that of cells from 16 normal individuals. Groups of control individuals and patients with juvenile (JP), rapidly progressive (RP) and adult periodontitis (AP) were formed. Blastogenic responsiveness was assessed after 72 and 120 h incubation by measuring the uptake of radioactive precursor into DNA. Bacterial preparations and mitogens used as stimulators included Bacteroides melaninogemcus (BMEL), Capnocytophaga (CAPNO), Fusobacterium nucleatum (FUSO), Actinomyces viscosus (AVIS), phytohemagglutinin (PHA), and pokeweed mitogen (PWM). When the data were calculated as Stimulation Index (E/C), responsiveness of cells from patients with AP and JP was enhanced relative to that of cells from normal control subjects, but the enhancement was not statistically significant. In contrast, responsiveness of cells from RP patients to FUSO and AVIS was significantly suppressed. Except in the case of AP cells activated with PHA, mitogenic responsiveness of all patient cells was significantly suppressed. When responsiveness was calculated as E minus C, these differences between patient and control cells disappeared except for suppression of the level of blastogenesis by AP and RP cells exposed to AVIS. After 120 h incubation, unstimulated cultures of AP cells incorporated significantly less, and RP cells significantly more, radioactivity than did unstimulated cultures from normal individuals indicating an abnormal autologous mixed lymphocyte reaction. Cells were harvested and tested from a group of AP patients before, during and following periodontal therapy. PBM responsiveness to horaogenates of CAPNO did not change significantly during therapy, but responsiveness to all of the other bacterial preparations including autologous plaque increased following initial therapy. Values for AVIS, FUSO, and PLAQ were statistically significant. Responsiveness to the bacterial preparations either remained at the enhanced levels or increased to even greater levels following completion of therapy, except in the case of autologous plaque, where the values had begun to return toward pretreatment levels. In addition, responsiveness to PWM and PHA dropped to about one-half the pretreatment values and responsiveness of unstimtilated cultures increased significantly to levels observed in cultures of ceils from normal donors. 相似文献
923.
Extent of atypical hyperplasia stratifies breast cancer risk in 2 independent cohorts of women
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Amy C. Degnim MD William D. Dupont PhD Derek C. Radisky PhD Robert A. Vierkant MAS Ryan D. Frank MS Marlene H. Frost PhD Stacey J. Winham PhD Melinda E. Sanders MD Jeffrey R. Smith MD PhD David L. Page MD Tanya L. Hoskin MS Celine M. Vachon PhD Karthik Ghosh MD Tina J. Hieken MD Lori A. Denison Jodi M. Carter MD PhD Lynn C. Hartmann MD Daniel W. Visscher MD 《Cancer》2016,122(19):2971-2978
924.
Helicobacter pylori infects over 50% of the worldwide population. For eradication, European, Canadian, and American guidelines recommend a regimen consisting of a proton pump inhibitor, clarithromycin, and metronidazole or amoxicillin dosed twice daily for at least 7 days. When this treatment strategy fails, a complex, multidosed bismuth-based quadruple regimen is recommended. Unfortunately, for patients with heart failure, this salvage regimen can be potentially hazardous due to the drug-drug interaction with tetracycline and digoxin, as well as the large salicylate content with bismuth subsalicylate. As H. pylori infection is so prevalent, providers will most likely encounter such a therapeutic dilemma. A safe, effective, and simplistic alternative is a 10-day fluoroquinolone-based regimen consisting of a proton pump inhibitor, levofloxacin and either clarithromycin or amoxicillin. Levofloxacin demonstrates excellent bioavailability, widespread tissue and fluid distribution, extended half-life, limited drug interaction profile, low incidence of side effects, and remarkable activity against H. pylori with minimal primary resistance. Compared to the 7-day quadruple regimen, a 10-day levofloxacin-based regimen demonstrated a greater eradication rate, better tolerability, and a lower rate of therapy discontinuation. We briefly provide a summary of the data regarding this levofloxacin-based regimen and two successful cases from our heart failure clinic. 相似文献
925.
926.
Baum MK Jayaweera DT Duan R Sales S Lai S Rafie C Regev A Page JB Berkman R Campa A 《Journal of addictive diseases》2008,27(2):37-48
HIV/HCV co-infection is becoming one of the main causes of death in HIV+ persons. We determined quality of life, clinical symptoms and health care utilization in HIV mono-infected and HIV/HCV co-infected chronic drug users. After consenting 218 HIV+ drug users, a physical examination and questionnaires on demographics, quality of life, drugs of abuse, and healthcare utilization were completed. Blood was drawn for HCV status, CD4 cell count, HIV viral load, CBC and chemistry. HIV/HCV co-infected participants had significantly higher risk of having poorer perceived outlook and health, presented significantly more frequent depression and physical symptoms, and used significantly more healthcare services than those infected with HIV only, after adjusting for age, gender, ethnicity, CD4 cell count, and viral load. Diminished quality of life in the HIV/HCV co-infected group was explained by increased frequency of depression, physical symptoms, healthcare utilization, and poor access to HCV treatment in this population. 相似文献
927.
This study examined alcohol use and related social normative perceptions among a sample of 1,886 Central-Eastern European high school students. The youth represented in the study averaged 16.5 years of age and were from several localities in the countries of Hungary, Slovakia, Czech Republic, and Romania. Data for the study were collected through a school-based alcohol use survey that was completed in June 2005. Our results support the hypothesis that drinking was related to perception of the prevalence of alcohol use by schoolmates and by the number of friends who drink and/or engage in episodic heavy drinking. Specific implications of findings in terms of substance use prevention are discussed. In addition, the need for future research and the limitations of the current research are discussed. This study was largely financially supported through an international grant from the College of Health and Human Performance, Brigham Young University. 相似文献
928.
Crosignani S Page P Missotten M Colovray V Cleva C Arrighi JF Atherall J Macritchie J Martin T Humbert Y Gaudet M Pupowicz D Maio M Pittet PA Golzio L Giachetti C Rocha C Bernardinelli G Filinchuk Y Scheer A Schwarz MK Chollet A 《Journal of medicinal chemistry》2008,51(7):2227-2243
A novel chemical class of potent chemoattractant receptor-homologous expressed on Th2 lymphocytes (CRTH2 or DP2) antagonists is reported. An initial and moderately potent spiro-indolinone compound ( 5) was found during a high-throughput screening campaign. Structure-activity relationship (SAR) investigation around the carboxylic acid group revealed that changes in this part of the molecule could lead to a reversal of functional activity, yielding weakly potent agonists. SAR investigation of the succinimide functional group led to the discovery of several single-digit nanomolar antagonists. The potency of these compounds was confirmed in a human eosinophil chemotaxis assay. Moreover, compounds ( R)- 58 and ( R)- 71 were shown to possess pharmacokinetic properties suitable for development as an orally bioavailable drug. 相似文献
929.
Zhang Y Burgess JP Brackeen M Gilliam A Mascarella SW Page K Seltzman HH Thomas BF 《Journal of medicinal chemistry》2008,51(12):3526-3539
Structure-activity relationships (SARs) of 1 (SR141716) have been extensively documented, however, the conformational properties of this class have received less attention. In an attempt to better understand ligand conformations optimal for receptor recognition, we have designed and synthesized a number of derivatives of 1, including a four-carbon-bridged molecule (11), to constrain rotation of the diaryl rings. Computational analysis of 11 indicates approximately 20 kcal/mol energy barrier for rotation of the two aryl rings. NMR studies have determined the energy barrier to be approximately 18 kcal/mol and suggested atropisomers could exist. Receptor binding and functional studies with these compounds displayed reduced affinity and potency when compared to 1. This indicates that our structural modifications either constrain the ring systems in a suboptimal orientation for receptor interaction or the introduction of steric bulk leads to disfavored steric interactions with the receptor, and/or the relatively modest alterations in the molecular electrostatic potentials results in disfavored Coulombic interactions. 相似文献
930.
Ohlsen RI Williamson R Yusufi B Mullan J Irving D Mukherjee S Page E Aitchison KJ Barnes TR 《Journal of psychopharmacology (Oxford, England)》2008,22(3):323-329
The Antipsychotic Non-Neurological Side-Effects Rating Scale (ANNSERS) was developed to provide a comprehensive measure for rating non-neurological adverse drug reactions (ADRs) to antipsychotics. Although there were already available measures that adequately rated specific non-neurological ADRs, such as sexual side effects, a need was identified for a scale that comprehensively rated the full range of non-neurological ADRs commonly seen across the spectrum of first and second generation antipsychotic drugs, including metabolic and autonomic ADRs. This article reports on work to establish the interrater reliability of an early version and a later, more comprehensive version of the ANNSERS (versions 1 and 2, v1 and v2, respectively). The measures were administered in London centres to patients treated with clozapine. Trained clinicians rated the patients simultaneously and independently. Interrater reliability on the scores was calculated using the kappa coefficient method. The results (mean kappa coefficients of 0.77 and 0.72, respectively) indicate that substantial interrater reliability was achieved for both versions. Items for which the main basis for rating was laboratory investigations rather than patient interview were largely excluded from this study, and kappas were also not calculated for items with a low frequency (less than 10%) of endorsement. Samples of patients on other antipsychotics would be required to reliably calculate kappa coefficients for these items. In conclusion, the ANNSERS represents a clinically applicable research innovation, with good interrater reliability on clinician judged items, which is now available for the comprehensive assessment of non-neurological ADRs to antipsychotics, to aid the processes of clinical audit, research and drug discovery. 相似文献