bluuebunny/crossref_metadata_2025_split huggingface dataset:
In situ expression of RANKL, RANK, osteoprotegerin and cytokines in osteoclasts of rat periodontal tissue
Authors: Ogasawara T. , Yoshimine Y. , Kiyoshima T. , Kobayashi I. , Matsuo K. , Akamine A. , Sakai H. 
Published: December 2003

Objectives:  This study examined the in situ expression of receptor activator of nuclear factor‐κB ligand (RANKL), receptor activator of nuclear factor‐κB (RANK), osteoprotegerin, interleukin‐1β (IL‐1β) and tumor necrosis factor α (TNFα) in the osteoclasts of rat periodontal tissue.Background:  In periodontal disease, osteoclasts cause resorption of the alveolar bone. The function of osteoclasts is regulated by interaction with periodontal ligament cells (PDLs). Furthermore, various kinds of molecules such as RANKL, RANK, osteoprotegerin, IL‐1β and TNFα are known to be related to the osteoclasts differentiation and function. It is therefore important to observe the expression of RANKL, RANK, osteoprotegerin and cytokines in osteoclasts and PDLs.Methods:  Four‐week‐old Wistar rats were used. Tooth movement was performed by the Waldo method, and the pathological bone resorption was induced. The demineralized maxillae and mandiblae were embedded with paraffin. In situ hybridization was performed to detect RANKL, RANK, osteoprotegerin, IL‐1β, and TNFα mRNAs in osteoclasts and other cells using the specific RNA probes, respectively.Results:  Both RANKL and RANK were concomitantly expressed in some osteoclasts. RANKL was also positive in osteoblasts and PDLs. No IL‐1β‐ and TNFα‐positive osteoclast was noted. The positive signals of osteoprotegerin were detected in almost all osteoblasts, PDLs and odontoblasts. No osteoprotegerin‐positive osteoclasts were observed. The number and the distribution pattern of RANKL‐ and RANK‐expressing osteoclasts changed when orthodontic excessive force was applied to periodontal tissue. In addition, IL‐1β and TNFα were shown to be expressed in osteoclasts under pathological status.Conclusion:  These findings suggest that an autocrine mechanism of RANKL–RANK exists in osteoclast, which is heightened in the pathological conditions. Furthermore, the autocrine mechanism of IL‐1β and TNFα is also provided in osteoclast under pathological condition. These autocrine mechanisms therefore seem to regulate the osteoclast function in both physiological and pathological conditions.
The effect of centrifugal force on mRNA levels of collagenase, collagen type‐I, tissue inhibitors of metalloproteinases and β‐actin in cultured human periodontal ligament fibroblasts
Authors: Redlich M. , Roos H. , Reichenberg E. , Zaks B. , Grosskop A. , Bar Kana I. , Pitaru S. , Palmon A. 
Published: December 2003

Background:  The aim of orthodontic treatment is to relocate teeth abnormally positioned in the jaws. This is achieved by application of continuous force on the tooth, which is immediately being sensed by the periodontal ligament (PDL), bone and the gingiva. Since the bony response is mediated by the PDL, tooth movement is primarily a PDL phenomenon.Objectives:  Thus, the purpose of the present study was to evaluate the direct effect of force (excluding the in vivo tissue response) on the molecular level of matrix metalloproteinase‐1 (MMP‐1) and collagen type‐I (Col‐I) in human PDL fibroblasts.Methods:  PDL cell culture flasks were centrifuged for 10, 20, 30, 60, 90 and 120 min by horizontal microplate rotor. The effect of force on mRNA levels of β‐actin, MMP‐1, Col‐I, tissue inhibitors‐1 and ‐2 (TIMPs) genes was analyzed by RT‐PCR.Results:  The results showed that force had no effect on the mRNA levels of β‐actin during the first 90 min of application of force, indicating for the first time the use of β‐actin gene as an internal invariant control. It increased the mRNA levels of MMP‐1 while almost no effect on Col‐I and TIMPs was observed.Conclusions:  The results indicate that PDL remodeling following application of orthodontic force could be partly attributed to the direct effect of the force on MMP‐1 gene expression in fibroblasts.
Accelerated alveolar bone loss in male HLA‐B27 transgenic rats: adult onset
Authors: May Natasha Y. , Tatakis Dimitris N. 
Published: December 2003

Objective and background:  HLA‐B27 transgenic (TG) rats exhibit severe colitis, arthritis and other inflammatory lesions. Previous studies in female TG rats indicate that they develop severe alveolar bone loss (ABL). Lack of data on male TG rats has left open the question of possible hormonal/sex dependence for the observed ABL. The purpose of the present study was to assess the natural history of ABL in male HLA‐B27 rats, compared to age‐ and sex‐matched wild‐type Fischer 344 (WT) rats.Materials and methods:  Fourteen WT and 11 TG male rats, aged 7–8 weeks, were used. Sacrifice times occurred at 10, 22 and 35 weeks. Animal heads were defleshed and treated to remove organic material, and skulls were stained to locate the cemento–enamel junction. ABL was measured as exposed molar root surface area (mm2) on the right maxilla and right mandible. Blinded measurements were performed using a computer‐assisted image analysis system.Results:  ABL for the entire TG group was significantly different from the WT group (p < 0.05). There was no significant difference in ABL between WT and TG rats at 10 weeks of age. At 22 and 35 weeks of age TG rats experienced 23% and 37% greater ABL than WT rats, respectively; these differences were statistically significant (p < 0.015). For both TG and WT animals, ABL was significantly different between the three age groups.Conclusions:  These results, consistent with previous findings in female TG rats, suggest that the accelerated ABL found in TG rats is an adult‐onset, age‐dependent, and sex‐independent process.
Mineralized bone loss in partially edentulous trabeculae of ovariectomized rabbit mandibles
Authors: Cao T. , Shirota T. , Ohno K. , Michi K. I. 
Published: December 2003

Objective:  The purpose of this study was to evaluate trabeculae changes in partially edentulous bone in ovariectomized rabbits.Background:  Numerous clinical studies have suggested that the greater risk for oral bone loss in females may be correlated with osteoporosis after menopause. Knowledge of trabecular changes in partially edentulous bone in animals with loss of ovarian function may be beneficial in the diagnosis and treatment of partially edentulous patients of postmenopausal women.Methods:  Twelve adult female Japanese white rabbits were examined. The mandibular incisors were initially extracted to simulate the partially edentulous bone. Six animals were bilaterally ovariectomized and the other six sham‐ovariectomized 12 weeks after tooth extraction. The partially edentulous parts of distal mandibular bodies were processed undecalcified 12 weeks after ovariectomized or sham‐ovariectomized surgeries and examined by quantitative trabecular bone histomorphometry.Results:  In ovariectomized rabbits, there were significant increases in trabecular separation, osteoid volume, osteoid thickness, osteoid width, eroded surface, and mineral apposition rate, and a significant decrease in trabecular number.Conclusion:  The results of sparser trabecular structure, more trabecular osteoid, and increased trabecular bone turnover demonstrate mineralized bone loss in partially edentulous trabeculae of ovariectomized rabbit mandibles and suggest that the same loss may occur in postmenopausal women.
Vigabatrin‐induced modification of Ki‐67 expression in gingival epithelium: immunohistochemical study of a short series
Authors: Mesa F. , Aguilar M. , Gonzalez‐Moles M. A. , Guerrero A. , Sanchez‐Alvarez J. C. , Del Moral R. G. , O'Valle F. 
Published: December 2003

Objective:  To study the expression and role in vigabatrin (VGB)‐induced gingival enlargement of Ki‐67 antigen and p27KIP1, p21WAF1, and p53, proteins that activate or inhibit cell‐cycle progression.Materials and methods:  Six patients treated with VGB for partial epileptic seizures refractory to classic anticonvulsant treatment were studied. Gingival biopsies were taken from four of these patients for immunohistochemical studies; 10 control biopsies from individuals with healthy gingiva and 10 from patients with periodontal disease were also evaluated.Results:  Four of the six patients presented some degree of gingival enlargement (mild or moderate). Nuclear expression of Ki‐67 was elevated (mean of 894 positive cells/mm2 in VGB‐induced gingival enlargement vs. 391 cells/mm2 in controls with healthy gingiva and 425 cells/mm2 in controls with periodontal disease) (p < 0.01, analysis of variance: anova), and nuclear expression of cyclin‐dependent kinase (cdk) inhibitors p27KIP1 and p21WAF1 was reduced. The patients with gingival enlargement presented inflammatory infiltrate in lamina propria, mainly composed of T lymphocytes (CD3+) and plasma cells (CD38+), which was even more intense than in the biopsies of patients with periodontal disease.Conclusion:  The overexpression of antigen Ki‐67 and slight underexpression of cdk‐inhibitors p27KIP1 and p21WAF1 suggest that VGB induced an increase in cell proliferation and contributed, together with concomitant periodontal disease, to the gingival enlargement.
Detection of subgingival calculus and dentine caries by laser fluorescence
Authors: Kurihara Eriko , Koseki Takeyoshi , Gohara Kenjiro , Nishihara Tatsuji , Ansai Toshihiro , Takehara Tadamichi 
Published: December 2003

Objectives:  Detection of subgingival calculus and dentine caries in the bottom of deep periodontal pockets is often difficult without visual observation. We thus examined the possibility of its detection using autofluorescence induced by laser irritation.Methods:  Autofluorescence was measured at various excitation and emission wavelength settings in five specimens each of sound dentine and enamel, subgingival calculus, and root caries. Periodontopathic model teeth with bacterial cells and blood clots were also irritated by laser to obtain autofluorescent images.Results:  Subgingival calculus and dentine caries showed a characteristic 700 nm emission when excited at 635 nm or a 720 nm emission when excited at 655 nm; sound dentine or enamel, however, did not. The calculus differentiation power, however, was higher with excitation at 635 nm than at 655 nm. The autofluorescent images photographed at an excitation of 633 nm provided clear calculus identification in periodontopathic model teeth when a 700 nm band‐pass filter or a 700 nm high‐pass filter was used. However, fluorescence intensity was masked when the calculus surface was covered by bacterial cells or blood clots. For clinical use, it would be important to remove subgingival plaque and debris from root surfaces before attempting to detect subgingival calculus and root caries with this manner.Conclusion:  The autofluorescence method employing excitation of 633–635 nm was found to be a powerful tool for detecting subgingival calculus and root caries.
Outcome and Safety of Extracorporeal Shock Wave Lithotripsy as First-Line Therapy of Lower Pole Nephrolithiasis
Authors: Riedler Ildiko , Trummer Harald , Hebel Peter , Hubmer Gerhart 
Published: December 2003

<i>Introduction:</i> The aim of this study is to assess the efficiency of extracorporeal shock wave lithotripsy (ESWL) as initial therapy for isolated lower pole kidney stones smaller than 20 mm. <i>Patients and Methods:</i> During a 24-month period 116 patients with previously untreated single stones under 20 mm in diameter were treated with a Dornier lithotripter S. They were analyzed with regard to stone site and size, number of ESWL sessions, auxiliary measures, retreatment rates, complications and the time taken for stone clearance. <i>Results:</i> 76 patients (65.5%) became stone free, 50 of them (43.1%) within 3 months after ESWL. Depending on stone size the stone-free rates were 67.1% for patients with a stone diameter of <10 mm (59 of 88 patients), and 60.7% for stone diameters between 10 and 20 mm (17 of 28 patients). Complications during and after treatment were rare, i.e. the necessity of ureteral stent insertion due to colic (n = 10), endoscopic stone removal (n = 2), acute pyelonephritis (n = 1), stonestreet (n = 1) and 1 case of hematoma not requiring intervention. The recurrence rate during follow-up (13.2–36.9, mean 25.0 months) was low: 16 patients (13.8%) had recurrent or persistent stones, and 74 patients (63.8%) had no evidence of urolithiasis. <i>Conclusions:</i> ESWL is a safe and efficient first-line therapy for treatment of isolated small lower pole kidney stones with acceptable stone-free rates, low morbidity, few complications and a low stone recurrence rate.
Dichlorodiphenyltrichloroethane Specifically Depletes Dopaminergic Neurons in Primary Cell Culture
Authors: Leung K.W. , Chan Y.S. , Yung K.K.L. 
Published: December 2003

Toxicity of dichlorodiphenyltrichloroethane (DDT) to dopaminergic neurons in primary cell culture was investigated in the present study. Developing neurons from the substantia nigra of neonatal rats were cultured. After treatments with different concentrations of DDT (5– 12.5 µM), specific cell death of tyrosine-hydroxylase-immunoreactive dopaminergic neurons was observed in the culture by flow cytometric analysis. More than 60% of dopaminergic neurons were depleted after treatments with 10 and 12.5 µM of DDT. In addition, significant reductions of intensity levels of tyrosine hydroxylase immunofluorescence were observed in dopaminergic neurons after DDT treatments even at low concentrations of DDT. The present findings indicate that dopaminergic neurons are more susceptible to DDT toxicity than other types of neurons in the primary cell culture. Moreover, it is shown that the synthesis of dopamine in dopaminergic neurons is also depressed. Previous studies have demonstrated that perinatal exposure of DDT causes neurons to be more susceptible to neurotoxic damages in later adult life. The present findings thus provide evidence that dopaminergic neurons that are undergoing growth and development are targets of DDT neurotoxic effects. Exposure to DDT from contaminated environments is therefore a potential risk of onset of Parkinson’s disease.
Isolation of chromosomal regions controlling intersex development in a marsupial
Authors: Santucciu C. , Grützner F. , Carvalho-Silva D.R. , Graves J.A.M. 
Published: December 2003

A marsupial <i>(Sminthopsis douglasi)</i> with bilateral intersexuality had a hemiscrotum on the right side and a hemi-pouch with nipples on the left. A normal female karyotype (2n = 14, XX) was present in cells from the right (male) side, while cells from the left (female) side initially had a female karyotype plus two dot-like chromosomes (2n = 14, XX + 2B). It is proposed that the dots represented a region deleted from the X chromosome that contains the “pouch-mammary/scrotum” (PMS) switch gene whose dosage determines development of a pouch and teats (two doses) or a scrotum (one dose). Mis-segregation early in embryonic development produced a lineage with one normal X and one deleted X (male side), and a lineage with a normal and deleted X, plus two copies of the deleted region (female side). The origin of the supernumerary elements was therefore investigated in the expectation that they may contain the long-sought pouch-mammary/scrotum switch gene. Several elements were microdissected, and amplified DNA was used for in situ hybridization, producing signals in five different chromosome regions including the X. This could represent a region of the X that contains, as well as PMS, repetitive DNA that is present also at other chromosomal sites.
Correlation of Meropenem Plasma Levels with Pharmacodynamic Requirements in Critically Ill Patients Receiving Continuous Veno-Venous Hemofiltration
Authors: Krueger Wolfgang A. , Neeser Gertraud , Schuster Harald , Schroeder Torsten H. , Hoffmann Edgar , Heininger Alexandra , Dieterich Hans-Juergen , Forst Helmuth , Unertl Klaus E. 
Published: December 2003

<i>Background:</i> In patients with acute renal failure, the pharmacokinetics of meropenem depend on the operational characteristics of the renal replacement therapy. Dosage recommendations are based on the correlation of plasma levels with pharmacodynamic requirements. <i>Methods:</i> Eight critically ill patients with acute renal failure were treated by continuous veno-venous hemofiltration with a filtrate flow of 1,600 ml/h and received 500 mg of meropenem every 12 h. Plasma and hemofiltrate concentrations of meropenem at steady state were determined by HPLC. <i>Results:</i> Peak levels in plasma amounted to 39.5 ± 10.5 mg/l (mean ± SD) and trough levels were 2.4 ± 1.5 mg/l. The minimal inhibitory concentration (MIC) for susceptible bacteria (4 mg/l) was covered for 40% of the dosing interval or longer in all patients. The MIC for intermediately susceptible organisms (8 mg/l) was covered for 33% in 6 of the 8 patients. The elimination half-life was prolonged to 3.63 ± 0.77 h. The sieving coefficient of meropenem was 0.91 ± 0.10 and the recovery in hemofiltrate amounted to 30.9 ± 11.5% of the dose. <i>Conclusions:</i> A dosage of 500 mg twice daily provides appropriate serum levels for the treatment of infections caused by susceptible bacteria. A higher dosage is adequate for infections by intermediately susceptible bacteria or for renal replacement therapies with markedly higher filtrate flow rates.
Reoxygenation with 100 or 21% Oxygen after Cerebral Hypoxemia-Ischemia-Hypercapnia in Newborn Piglets
Authors: Solås Anne-Beate , Kalous Petr , Saugstad Ola D. 
Published: December 2003

We tested if reoxygenation with 100% O<sub>2</sub> was superior to 21% O<sub>2</sub> after combined cerebral hypoxemia-ischemia-hypercapnia (HIH) in newborn piglets. Twenty-eight piglets were randomized to reoxygenation with 100 or 21% O<sub>2</sub> following asphyxia. Asphyxia was induced by ventilation with 8% O<sub>2</sub>, adding CO<sub>2</sub>, and temporary occlusion of both common carotid arteries. After 20 min, reoxygenation-reperfusion was started with 21% O<sub>2</sub> (HIH 21% group, n = 13) or 100% O<sub>2</sub> (HIH 100% group, n = 11) for 30 min followed by 21% O<sub>2</sub>. All piglets were observed for 2 h. We measured mean arterial blood pressure (MABP), changes in microcirculation in the cerebral cortex (laser Doppler), and extracellular concentrations of hypoxanthine in the cortex and amino acids in the striatum (microdialysis). We found significantly higher MABP and better restoration of microcirculation after reoxygenation with 100% compared with 21% O<sub>2</sub>, but no differences in biochemical markers were found between the groups. This indicates that the brain tolerated reoxygenation with 21% as well as with 100% O<sub>2</sub> in the present model of experimental asphyxia in spite of the differences in MABP and cerebral microcirculation.
Expression and Phosphorylation of N-Methyl-<i>D</i>-Aspartate Receptor Subunits during Graded Hypoxia in the Cerebral Cortex of Newborn Piglets
Authors: Fritz Karen I. , Ashraf Qazi M. , Zubrow Alan B. , Mishra Om P. , Delivoria-Papadopoulos Maria 
Published: December 2003

The present study tests the hypothesis that during graded hypoxia, N-methyl-<i>D</i>-aspartate (NMDA) receptor expression and phosphorylation are altered in the cerebral cortex of newborn piglets. Studies were performed in anesthetized, ventilated piglets, 6 normoxic and 9 exposed to different lengths of decreased fractions of inspired oxygen to achieve varying biochemical levels of phosphocreatine (PCr). P<sub>2</sub> membrane proteins were immunoprecipitated with antiphosphoserine, antiphosphotyrosine, or antiphosphothreonine antibodies and separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins were transblotted and probed with NMDA receptor subunit 1 (NR1), NR2A or NR2B antibodies. As tissue PCr levels decreased from 3.5 to 0.5 µmol/g brain during hypoxia, NR1, NR2A and NR2B protein increased by 84, 56 and 38%, respectively. Phosphorylated serine, tyrosine and threonine residues also increased during hypoxia on the three subunits. However, the increase in subunit protein exceeded the increase in phosphorylated residues for all three subunits. Therefore, the ratio of phosphorylated/dephosphorylated serine, tyrosine and threonine residues decreased with worsening hypoxia. We speculate that an alteration in the ratio of phosphorylated/dephosphorylated residues of the NMDA receptor may regulate receptor activation during hypoxia.
Supplementation of Female Rats with α-Linolenic Acid or Docosahexaenoic Acid Leads to the Same Omega-6/Omega-3 LC-PUFA Accretion in Mother Tissues and in Fetal and Newborn Brains
Authors: Valenzuela Alfonso , von Bernhardi Rommy , Valenzuela Viviana , Ramírez Gigliola , Alarcón Rodrigo , Sanhueza Julio , Nieto Susana 
Published: December 2003

<i>Background:</i> Maternal omega-3 fatty acid supplementation has been suggested to provide docosahexaenoic acid (DHA) for the normal brain development during gestation. DHA can be given as such (preformed) or through the omega-3 precursor alpha-linolenic acid (LNA) which is transformed into DHA by elongation and desaturation reactions. Western diet provides low amounts of LNA and DHA; therefore, supplementation with these omega-3 fatty acids has been suggested for pregnant women. However, the bioequivalence of LNA ingestion to DHA supplementation has not been established. <i>Methods:</i> Recently weaning female Wistar rats were fed a diet containing a small amount of LNA and no DHA. The animals were daily supplemented 40 days before mating, during pregnancy, and until delivery with 60 mg/kg of LNA or 6 mg/kg of DHA dissolved in coconut oil. Fatty acids were given as ethyl ester derivatives. Controls received coconut oil. The fatty acid composition of blood plasma, erythrocytes, liver, visceral adipose tissue, and brain segments (frontal cortex, hippocampus, and cerebellum) was analyzed. Brain segments obtained from 16- and 19-day-old fetuses and from 2- and 21-day-old rats were also analyzed for fatty acid composition. <i>Results:</i> Supplementation with LNA and DHA induced a similar accretion of DHA in plasma, erythrocytes, liver, and brain segments of the mothers. The adipose tissue showed a higher DHA accretion after DHA-supplementation. The DHA accretion in frontal cortex, hippocampus, and cerebellum obtained from the fetuses and the newborn rats was similar when the mothers were supplemented with LNA and DHA. Our results show that under our experimental conditions a similar accretion of DHA in the different tissues of the mothers and in the brain segments of fetuses and newborn rats is obtained after LNA and DHA supplementation. <i>Conclusion:</i> LNA and DHA, at the amounts given in this study, show a similar bioequivalence for DHA accretion in different tissues of the mother and in brain segments of fetuses and newborn rats.