Community Analysis-based Screening of Plant Growth-promoting Bacteria for Sugar Beet.

Clone libraries of bacterial 16S rRNA genes (a total of 1,980 clones) were constructed from the leaf blades, petioles, taproots, and lateral roots of sugar beet (Beta vulgaris L.) grown under different fertilization conditions. A principal coordinate analysis revealed that the structures of bacterial communities in above- and underground tissues were largely separated by PC1 (44.5%). The bacterial communities of above-ground tissues (leaf blades and petioles) were more tightly clustered regardless of differences in the tissue types and fertilization conditions than those of below-ground tissues (taproots and lateral roots). The bacterial communities of below-ground tissues were largely separated by PC2 (26.0%). To survey plant growth-promoting bacteria (PGPBs), isolate collections (a total of 665 isolates) were constructed from the lateral roots. As candidate PGPBs, 44 isolates were selected via clustering analyses with the combined 16S rRNA gene sequence data of clone libraries and isolate collections. The results of inoculation tests using sugar beet seedlings showed that eight isolates exhibited growth-promoting effects on the seedlings. Among them, seven isolates belonging to seven genera (Asticcacaulis, Mesorhizobium, Nocardioides, Sphingobium, Sphingomonas, Sphingopyxis, and Polaromonas) were newly identified as PGPBs for sugar beet at the genus level, and two isolates belonging to two genera (Asticcacaulis and Polaromonas) were revealed to exert growth-promoting effects on the plant at the genus level for the first time. These results suggest that a community analysis-based selection strategy will facilitate the isolation of novel PGPBs and extend the potential for the development of novel biofertilizers.

Optimal timing of video-assisted thoracoscopic surgery for patent ductus arteriosus in preterm infants born at ≤ 28 weeks of gestation.

BACKGROUND: Video-assisted thoracoscopic surgery for patent ductus arteriosus (VATS-PDA) is an alternative surgical procedure to open chest surgery, even in premature infants. This study investigated whether the timing of VATS-PDA has a prognostic impact in premature infants whose operative indication was determined according to the symptomatic PDA and the ineffectiveness of or contraindication to indomethacine therapy. METHODS: We studied 49 infants born at or before 28 weeks of gestation who were admitted to the neonatal intensive care unit between January 2004 and June 2016, and who underwent VATS-PDA. The patients were divided into two groups according to median age at the time of surgery (early group, 24 infants who underwent surgery at ≤ 24 days of life; late group, 25 infants who underwent surgery at ≥ 25 days of life). RESULTS: No significant differences were found in bodyweight at 30 days of age and 40 weeks of corrected gestational age between the groups. The timing of surgery did not affect the operative procedure or postoperative complications. In addition, no differences were observed between the early and late groups in terms of complications associated with prematurity, including intraventricular hemorrhage, incidence and severity of bronchopulmonary dysplasia, and necrotizing enteropathy. CONCLUSION: Video-assisted thoracoscopic surgery for patent ductus arteriosus can be safely performed in premature infants without a preferential timing for the intervention, suggesting that this procedure allows for an elective basis approach after heart failure management with conservative and/or drug therapy in premature infants with PDA.

Thyroid Function in Patients With a Fontan Circulation.

In this study, we tested our hypothesis that thyroid function is impaired and contributes to perturbed hemodynamics in patients after Fontan operation. Cardiac catheterization and blood tests for thyroid function were performed in 37 patients who underwent a Fontan operation. Among them, 12 patients (33%) had subclinical thyroid dysfunction with an elevated thyroid-stimulating hormone level despite normal thyroxine levels. Thyroid-stimulating hormone levels were significantly correlated with central venous pressure (p <0.01, R2 = 0.3), and patients with subclinical hypothyroidism showed significantly elevated γ-glutamyltransferase level, an indicator of liver congestion, compared with the other patients (125.6 ± 12.2 vs 67.6 ± 4.6 IU/L, p <0.01). In addition, the levels of free triiodothyronine, an effective thyroid hormone, were significantly lower in patients with subclinical hypothyroidism than in those with normal thyroid function (3.1 ± 0.1 vs 3.5 ± 0.1 pg/dl, p <0.01). The free triiodothyronine level was significantly and negatively correlated with the relaxation time constant (p = 0.03) and brain natriuretic hormone (p <0.01) level and positively correlated with the cardiac index (p = 0.04). In conclusion, venous congestion in Fontan patients may cause thyroid dysfunction, which can be responsible for decreased ventricular function and cardiac output in Fontan patients. Thus, thyroid function should be routinely monitored after Fontan surgery.

Lithium chloride reduces orthodontically induced root resorption and affects tooth root movement in rats.

OBJECTIVE: To investigate the influence of lithium chloride (LiCl) on orthodontic tooth movement (OTM), orthodontically induced root resorption (OIRR), and bone morphometry. MATERIALS AND METHODS: Ten-week-old female Sprague Dawley rats (n = 32) were divided into four groups based on the concentration of LiCl administered daily per kilogram body weight: 0 (control group), 0.32, 0.64, and 1.28 mM/kg body weight. The maxillary left first molars were moved mesially by a 10 cN coil spring for 14 days. Micro-computed tomography, scanning electron microscope, and scanning laser microscope images were taken to measure the amount of OTM, the volume of OIRR, and bone morphometry. RESULTS: OIRR clearly decreased depending on the amount of LiCl administered, although OTM moderately decreased. The tooth inclined mesially and the root apex moved distally in the control and 0.32 mM groups. On the other hand, the tooth inclination angle became smaller and the root apex moved mesially in the 0.64 and 1.28 mM groups. In bone morphometry, the cortical bone mineral content and bone volume increased because of LiCl administration, and the trabecular bone measurements decreased. OIRR negatively correlated to the cortical bone measurements, and the amount of OTM significantly correlated to the cortical bone morphometry. CONCLUSIONS: In rats, LiCl reduced OIRR, which induced mesial movement of the tooth root apex. OIRR positively correlated to cortical bone morphometry.

Types of tooth movement, bodily or tipping, do not affect the displacement of the tooth's center of resistance but do affect the alveolar bone resorption.

OBJECTIVE: To investigate how types of tooth movement, bodily or tipping, influence the displacement of the center of resistance in teeth and alveolar bone resorption. MATERIALS AND METHODS: Ten-week-old female Wistar rats were divided into eight groups of different factors, as follows: type of movement (bodily and tipping) and force magnitude (10, 25, 50, and 100 cN). The maxillary left first molars were moved mesially with nickel-titanium coil springs for 28 days. Micro-computed tomography (micro-CT) images were taken before and after tooth movement. The position of the center of resistance was determined by using finite element models constructed from the micro-CT image. The displacement of the center of resistance and the volume of alveolar bone resorption were measured. RESULTS: The displacement of the center of resistance showed no significant difference between the bodily and tipping groups. The displacements of the center of resistance were increased with force magnitude at 10 and 25 cN, whereas they were not further increased at 50 and 100 cN. On the other hand, cervical alveolar bone resorption was significantly greater in the tipping group than in the bodily group. CONCLUSIONS: Displacement of the center of resistance was not influenced by the types of tooth movement. However, volume of cervical alveolar bone resorption was greater in the tipping movement group than in the bodily movement group.

Increasing the amount of corticotomy does not affect orthodontic tooth movement or root resorption, but accelerates alveolar bone resorption in rats.

Objectives: The purpose of this study was to evaluate the relationships among the volume of bone cut during corticotomy, amount of tooth movement, volume of root resorption, and volume of the resultant alveolar bone resorption after tooth movement. Methods: Ten-week-old female Wistar rats were distributed into the corticotomy groups and a control group that underwent sham corticotomy. Two experiments employing two different orthodontic forces (10 or 25g) and experimental periods (14 or 21 days) were performed. The volumes of the bone cut by corticotomy were 0.1, 1.0, and 1.7mm3 in the 25g groups, and 1.0 and 1.7mm3 in the 10g groups. Nickel-titanium closed-coil springs were set on the maxillary left first molars to induce mesial movement. After orthodontic tooth movement, the amount of tooth movement, volume of root resorption, and volume of alveolar bone resorption were measured. Results: Despite differences in the volume of bone cut among the different corticotomy groups, there were not significant differences in the amount of tooth movement and volume of root resorption between the control group and any of the corticotomy groups. However, higher volume of bone cut during corticotomy was significantly related to the decreased alveolar bone volume-in particular, to the reduced height of the alveolar bone crest after tooth movement. Conclusions: The volume of the alveolar bone cut during corticotomy does not affect tooth movement or root resorption in 10-week-old female Wistar rats; however, it may increase alveolar bone loss after tooth movement.

A Patient With Aspiration Pneumonia After Mandibular Osteotomy With Genioplasty.

Orthognathic surgery including maxillary osteotomy, mandibular osteotomy, and genioplasty is a reliable treatment strategy for jaw deformity. However, there are some complications associated with these surgeries, including neurovascular damage and abnormal bleeding. The authors present here a patient of aspiration pneumonia after mandibular osteotomy.An 18-year-old female patient underwent sagittal split ramus osteotomy and genioplasty for mandibular prognathism. She began choking and coughing immediately after surgery. She was diagnosed with aspiration pneumonia based on chest radiography and computed tomography findings. Her hyoid bone was shifted 23 mm inferiorly after surgery, and this movement may have caused swallowing dysfunction. She was treated with intravenous antibiotics and discharged on the 18th postoperative day.Although the hyoid bone is transiently shifted inferiorly by mandibular setback with or without genioplasty, this shift does not usually affect swallowing function. Damage to the suprahyoid muscles during genioplasty may cause both an inferior shift and dysmobility of the hyoid bone. Therefore, surgeons must be careful not to damage the suprahyoid muscles at the lingual site osteotomy in genioplasty to avoid this complication.

[Levobupivacaine for Ultrasound-guided Interscalene Block: Block with 6 ml Leads to Less Occurrence of Respiratory Depression and Hemidiaphragmatic Paralysis].

BACKGROUND: Interscalene brachial plexus block (ISBPB) complications depend usually on the dose administered. METHODS: The object of this study was to determine whether ultrasound-guided ISBPB with 6 ml of 0.5% levobupivacaine would reduce occurrence of respiratory depression and hemidiaphragmatic paralysis. RESULTS: Patients undergoing arthroscopic shoulder surgery under nerve block with general anesthesia (n = 20) were recruited. There were no differences between pre and post operative respiratory function (forced expiratory volume 1.0 (sec) % and vital capacity). Hemidiaphragmatic paralysis on postoperative ultrasonography was found in two patients. CONCLUSIONS: The use of low-volume ultrasound-guided ISBPB is associated with less respiratory depression and hemidiaphragmatic paralysis.

[Ultrasoud-guided paravenous approach for saphenous nerve block in ankle surgery].

BACKGROUND: Blocking conduction in the saphenous nerve is important in providing surgical anesthesia of the lower leg. The aim of this retrospective study was to determine the efficacy of ultrasound-guided paravenous approach for saphenous nerve block. METHODS: Twenty-eight patients underwent ankle surgery after saphenous nerve block using ultrasoud-guided paravenous approach below the knee combined with sciatic nerve block under general anesthesia. Sensory blockade was evaluated at the upper part of the leg as compared with the contralateral leg. RESULTS: Twenty four patients (85%) had sensory blockade on the day of the surgery. Six patients (21%) had sensory blockade the day after surgery. CONCLUSIONS: Paravenous approach for saphenous nerve block may be effective particularly with limited resources.

Metagenomic analysis of the bacterial community associated with the taproot of sugar beet.

We analyzed a metagenome of the bacterial community associated with the taproot of sugar beet (Beta vulgaris L.) in order to investigate the genes involved in plant growth-promoting traits (PGPTs), namely 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, indole acetic acid (IAA), N2 fixation, phosphate solubilization, pyrroloquinoline quinone, siderophores, and plant disease suppression as well as methanol, sucrose, and betaine utilization. The most frequently detected gene among the PGPT categories encoded ß-1,3-glucanase (18 per 10(5) reads), which plays a role in the suppression of plant diseases. Genes involved in phosphate solubilization (e.g., for quinoprotein glucose dehydrogenase), methanol utilization (e.g., for methanol dehydrogenase), siderophore production (e.g. isochorismate pyruvate lyase), and ACC deaminase were also abundant. These results suggested that such PGPTs are crucially involved in supporting the growth of sugar beet. In contrast, genes for IAA production (iaaM and ipdC) were less abundant (~1 per 10(5) reads). N2 fixation genes (nifHDK) were not detected; bacterial N2 -fixing activity was not observed in the (15)N2 -feeding experiment. An analysis of nitrogen metabolism suggested that the sugar beet microbiome mainly utilized ammonium and nitroalkane as nitrogen sources. Thus, N2 fixation and IAA production did not appear to contribute to sugar beet growth. Taxonomic assignment of this metagenome revealed the high abundance of Mesorhizobium, Bradyrhizobium, and Streptomyces, suggesting that these genera have ecologically important roles in the taproot of sugar beet. Bradyrhizobium-assigned reads in particular were found in almost all categories of dominant PGPTs with high abundance. The present study revealed the characteristic functional genes in the taproot-associated microbiome of sugar beet, and suggest the opportunity to select sugar beet growth-promoting bacteria.

Tongue pressure during swallowing in adults with down syndrome and its relationship with palatal morphology.

In individuals with Down syndrome, hypotonicity of the tongue and an underdeveloped maxilla may lead to poor oral motor coordination, which adversely affects the oral phase of swallowing. This study aimed to evaluate the characteristics of pressure produced by the tongue against the hard palate during swallowing in individuals with Down syndrome. In addition, the relationship between tongue pressure and palatal morphology was examined. We studied nine adults with Down syndrome and ten healthy adults as controls. Tongue pressure while swallowing 5 mL water was recorded by a sensor sheet system with five measuring points attached to the hard palate. Palatal length, depth, width, curvature, and slope were measured by three-dimensional digital maxillary imaging. The order of onset of tongue pressure on the median line of the hard palate was the same in all participants, except for three with Down syndrome. The duration and maximal magnitude of tongue pressure on the median line in nine participants with Down syndrome were significantly shorter and lower than those of controls. In participants with Down syndrome, significant positive correlations were observed between the duration of tongue pressure at the mid-median part of the hard palate and palatal depth and width, and between the duration and maximal magnitude of tongue pressure at the posterior-median part and palatal length. These findings suggest that impaired tongue activity, poor tongue control, and constrained tongue motion due to a short and narrow palate contribute to swallowing difficulty in individuals with Down syndrome.

Effects of different types of tooth movement and force magnitudes on the amount of tooth movement and root resorption in rats.

OBJECTIVE: To investigate differences in the amount of tooth movement and root resorption that occurred after tipping and bodily movement of the maxillary first molar in rats. MATERIALS AND METHODS: Ten-week-old female Wistar rats were divided into two groups according to type of tooth movement and subdivided into four subgroups according to the magnitude of applied force. Nickel-titanium closed-coil springs exerting forces of 10, 25, 50, or 100 g were applied to the maxillary left first molars to induce mesial tooth movement. We designed a novel orthodontic appliance for bodily tooth movement. Tooth movement distance and root resorption were measured using microcomputed tomography and scanning electron and scanning laser microscopy. RESULTS: The amount of tooth movement in the bodily tooth movement group was less than half that in the tipping tooth movement group. The greatest amount of tooth movement occurred in the 10-g tipping and 50-g bodily tooth movement subgroups, and the amount of tooth movement decreased with the application of an excessive magnitude of force. Conversely, root resorption increased when the heavier orthodontic force was applied in both groups. Root resorption in the tipping tooth movement group was approximately twice that in the bodily tooth movement group. CONCLUSIONS: Root resorption in the tipping tooth movement group was more pronounced than that in the bodily tooth movement group. Although the amount of tooth movement decreased when extremely heavy forces were applied, root resorption increased in both the tipping and bodily tooth movement groups in rats.

Elective use of an uncuffed small-bore cricothyrotomy tube with balloon occlusion of the subglottic airway.

PURPOSE: To conduct a qualitative observational study on positive pressure ventilation through a percutaneous uncuffed small-bore cricothyrotomy tube with balloon occlusion of the subglottic airway to minimize supraglottic leak. CLINICAL FEATURES: Ten consecutive procedures were performed in the nine men enrolled in this study. The demographics of the participants were: aged 50-73 yr, weight 48-87 kg, American Society of Anesthesiologists class I-II, and scheduled for endoscopic submucosal dissection via flexible endoscopy for en bloc resection of superficial meso- and hypopharyngeal cancer. The airway was initially secured with a supraglottic airway (SGA) under sevoflurane-based anesthesia, and a cricothyrotomy was then performed using a Portex(®) Minitrach II uncuffed cricothyrotomy tube (4-mm internal diameter). Following SGA removal, a Coopdech(®) bronchial blocker was orally or nasally inserted, and the balloon was inflated to occlude the trachea immediately beneath the glottis. The ventilator setting was initially based on observation of chest motion and end-tidal carbon dioxide tension and then readjusted according to arterial blood gas levels. All procedures were completed within a median time of 149 min. Effective ventilation was achieved in all patients despite mild hypercapnia (PaCO2 of 58 mmHg at maximum) in some patients. SpO2 levels were maintained at ≥ 98%. CONCLUSION: This technique provides effective intraoperative ventilation and easy endoscopic access, and it countermeasures against the likely complication of postoperative laryngeal edema. Moreover, there is no need for conventional tracheostomy or prolonged intubation. This approach establishes a curative and less invasive pharyngeal cancer therapy. Certain adverse outcomes can be avoided, including impaired speech and swallowing, possible delayed closure of the stoma, or a compromised cosmetic outcome.

The AERO system: a 3D-like approach for recording gene expression patterns in the whole mouse embryo.

We have recently constructed a web-based database of gene expression in the mouse whole embryo, EMBRYS (http://embrys.jp/embrys/html/MainMenu.html). To allow examination of gene expression patterns to the fullest extent possible, this database provides both photo images and annotation data. However, since embryos develop via an intricate process of morphogenesis, it would be of great value to track embryonic gene expression from a three dimensional perspective. In fact, several methods have been developed to achieve this goal, but highly laborious procedures and specific operational skills are generally required. We utilized a novel microscopic technique that enables the easy capture of rotational, 3D-like images of the whole embryo. In this method, a rotary head equipped with two mirrors that are designed to obtain an image tilted at 45 degrees to the microscope stage captures serial images at 2-degree intervals. By a simple operation, 180 images are automatically collected. These 2D images obtained at multiple angles are then used to reconstruct 3D-like images, termed AERO images. By means of this system, over 800 AERO images of 191 gene expression patterns were captured. These images can be easily rotated on the computer screen using the EMBRYS database so that researchers can view an entire embryo by a virtual viewing on a computer screen in an unbiased or non-predetermined manner. The advantages afforded by this approach make it especially useful for generating data viewed in public databases.

[Case of delayed awakening after remifentanil leakage out of a vein].

We report a case of delayed awakening with characteristic repeated loss of consciousness after remifentanil infusion complicated by leakage from an intravenous catheter. A 30-year-old male underwent microlaryngeal surgery for a vocal cord polyp. During anesthetic induction, infiltration from an intravenous (IV) line in the left forearm was observed 10 min after initiating a continuous infusion of remifentanil 0.5 microg x kg-1 x min -1. A second peripheral IV catheter was placed in the right forearm and general anesthesia was induced with remifentanil infusion at 0.3 microg x kg-1 x min- 1, propofol 120mg, fentanyl 100 microg, and rocuronium 70 mg. Anesthesia was maintained with remifentanil 0.05-0.3 microg x kg-1 x min -1and sevoflurane (1.5% in oxygen) for the 4 min of surgery. A few minutes after tracheal extubation, the patient developed respiratory arrest and loss of consciousness. We immediately ventilated him with a bag-valve-mask and administered naloxone 0.04 mg. Thereafter, he repeatedly awoke and was drowsy three times over the next 5hr. It was followed by an uneventful postoperative period. No remarkable deficit was observed in the patient. Blood gases, electrolytes, glucose values, and body temperature were within normal ranges throughout the perioperative period. Brain computed tomography, mag- netic resonance imaging, and electroencephalography showed no abnormalities. It was considered that the incidental subcutaneous remifentanil accumulation may have caused the respiratory suppression and delayed awakening.

The effect of bone morphometric changes on orthodontic tooth movement in an osteoporotic animal model.

OBJECTIVE: To elucidate the effect of bone morphometric changes on orthodontic tooth movement (OTM) in zoledronic acid-treated ovariectomized rats. MATERIALS AND METHODS: Twenty-one 10-week-old female Wistar rats were divided into ovariectomy (OVX), OVX with zoledronic acid administration (OVX + ZOL), and sham operation (control) groups. Two weeks after OVX, ZOL administration was initiated. Twelve weeks after OVX, a nickel-titanium closed-coil spring of 25-g force was applied mesially to the maxillary left first molar. In vivo micro-computed tomography (CT) of the left proximal tibia was performed for bone morphometric analysis every 2 weeks after OVX. In addition, OTM was investigated using micro-CT at 0, 12, and 14 weeks after OVX. RESULTS: There were significant differences in the bone mineral content (BMC), bone volume (BV), BMC to tissue volume ratio (BMC/TV), and BV to TV ratio of trabecular bone between the control and OVX groups and also between the OVX + ZOL and OVX groups. In the OVX + ZOL group, increased BMC and BV in the cortical bone and increased bone mineral density (BMD) in the trabecular bone were observed. Interestingly, OTM in the OVX group was almost two times more than that in the control and OVX + ZOL groups. Moreover, OTM was correlated with BMD, BMC, BV, and BMC/TV in the trabecular bone. CONCLUSIONS: OVX accelerated OTM, while ZOL suppressed it. OTM demonstrated a significant negative relationship with trabecular bone mass.

Possible association between non-invasive parameter of flow-mediated dilatation in brachial artery and whole coronary plaque vulnerability in patients with coronary artery disease.

BACKGROUND: Despite being a relatively widely-used non-invasive parameter of endothelial dysfunction, little is known regarding the relationship between flow-mediated dilatation (FMD) and coronary plaque vulnerability in patients with coronary artery disease (CAD). METHODS: 111 CAD patients (age; 68.9 ± 9.3) who underwent both coronary intervention and FMD were enrolled. Spectral analyses of intravascular ultrasound radiofrequency data for both culprit and non-culprit lesions were performed using Virtual Histology software. Plaque burden was described based on fibrotic, fibro-fatty, dense calcium, and necrotic core (NC) components, and thin-cap fibroatheroma (TCFA) was defined as focal NC rich (> 10%) plaques touching the lumen with a percent-plaque volume exceeding 40%. RESULTS: Averaged %FMD was 2.86 ± 2.03% (median 2.27%, 25th 1.40%, 75th 4.20%). NC volumes were negatively correlated with log%FMD for both culprit and non-culprit lesions (P = 0.001, r = 0.31 and P = 0.03, r = 0.21, respectively). We divided the patients into three tertiles according to %FMD; 38 were lower (≤ 1.75%), 41 were middle (> 1.75%, but ≤ 3.5%), and 32 were upper tertile (> 3.5%). The prevalence rate of TCFA increased with decreasing %FMD tertile and the incidence of major adverse cardiac events was significantly higher in lower %FMD tertile. Multivariate logistic regression analyses showed that the most powerful predictive factor for TCFA was log%FMD (P < 0.0001), and ROC curve analysis identified %FMD of < 2.81% (AUC = 0.82, sensitivity: 91.2%, specificity: 66.7%) as the optimal cut-off point for predicting the presence of TCFA. CONCLUSIONS: Impaired endothelial function in brachial arteries may be associated with whole coronary plaque vulnerability and poor clinical outcome in patients with CAD.

Effect of renal impairment on the pharmacokinetics of memantine.

The effect of renal impairment on the pharmacokinetics of a single oral dose of memantine (10 mg) was determined in Japanese subjects. Subjects were assigned to four groups based on baseline creatinine clearance (CL(CR)): normal renal function (> 80 mL/min, n = 6), and mild (50 to ≤ 80 mL/min, n = 6), moderate (30 to < 50 mL/min, n = 6), and severe renal impairment (5 to < 30 mL/min, n = 7). Mean memantine maximum plasma concentration (C(max)) was similar in the groups (12.66, 17.25, 15.75, and 15.83 ng/mL, respectively), as was mean time to C(max) (6.2, 5.2, 4.3, and 5.4 h, respectively). However, exposure to memantine determined from mean area under the plasma concentration-time curve was 1.62-, 1.97-, and 2.33-times higher in subjects with mild, moderate, and severe renal impairment, respectively, as compared to controls with normal renal function. Mean memantine plasma elimination half-life increased according to increasing renal impairment (61.15, 83.00, 100.13, and 124.31 h, respectively), while mean cumulative urinary recovery of unchanged memantine in 72 h after dosing decreased according to increasing renal impairment (33.68%, 33.47%, 23.60%, and 16.17%, respectively). These results are the same as those in the previous study on caucasian individuals, when compared per body weight. It is suggested that the dose of memantine should be halved in patients with renal impairment.

Orthodontic tooth movement and root resorption in ovariectomized rats treated by systemic administration of zoledronic acid.

INTRODUCTION: The effect of zoledronic acid, a potent and novel bisphosphonate, on tooth movement and orthodontically induced root resorption in osteoporotic animals systemically treated with zoledronic acid as similarly used in postmenopausal patients has not been elucidated. Therefore, this study was undertaken. METHODS: Fifteen 10-week-old female Wistar rats were divided into 3 groups: ovariectomy, ovariectomy + zoledronic acid, and control. Only the ovariectomy and ovariectomy + zoledronic acid groups underwent ovariectomies. Two weeks after the ovariectomy, zoledronic acid was administered only to the ovariectomy + zoledronic acid group. Four weeks after the ovariectomy, 25-g nickel-titanium closed-coil springs were applied to observe tooth movement and orthodontically induced root resorption. RESULTS: There were significant differences in the amounts of tooth movement and orthodontically induced root resorption between the ovariectomy and the control groups, and also between the ovariectomy and the ovariectomy + zoledronic acid groups. There was no statistically significant difference in tooth movement and orthodontically induced root resorption between the ovariectomy + zoledronic acid and the control groups. Zoledronic acid inhibited significantly more tooth movement and significantly reduced the severity of orthodontically induced root resorption in the ovariectomized rats. The ovariectomy + zoledronic acid group showed almost the same results as did the control group in both tooth movement and orthodontically induced root resorption. CONCLUSIONS: Zoledronic acid inhibits excessive orthodontic tooth movement and also reduces the risk of severe orthodontically induced root resorption in ovariectomized rats.