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31.
A girl aged 2 years and 8 months came to our clinic for consultation with regard to unerupted primary mandibular bilateral central incisors. An intraoral examination revealed that the teeth had not emerged into the oral cavity and showed a tooth crown morphology similar to that of the primary mandibular incisors, which appeared in the lingual submucosal area outside of the mandibular dental arch. Periapical radiographs demonstrated that the tooth crowns of both affected teeth were severely displaced to the lingual side. Computed tomography examinations were performed to clarify the three-dimensional positions of the affected teeth and their permanent successors, which revealed that the affected teeth were located in their estimated positions and had a standard root morphology. In addition, the permanent successors, which had not initiated root formation, were located close to the affected teeth. We decided to postpone extraction of the affected teeth and perform periodical examinations until the roots of the permanent successors are sufficiently formed. At the age of 2 years and 10 months, the edge of the tooth crown of the primary mandibular left central incisor was found emerged into the oral cavity. According to her parents, the patient did not complain of the emerging edge and no abnormal conditions were observed around the tooth.  相似文献   
32.
Cysteinyl leukotriene and leukotriene receptor occupancy have been linked to several processes in seasonal allergic rhinitis (SAR), including nasal congestion, rhinorrhea, and recruitment of inflammatory cells. We investigated whether add-on loratadine, an antihistamine, might be effective for SAR patients showing unsatisfactory control of symptoms with the leukotriene receptor antagonist (LTRA) montelukast alone. Patients with SAR caused by Japanese cedar pollen (SAR-JCP; mean age, 29.4 years) were given prophylactic montelukast for 1 month before peak JCP dispersal. Patients recorded the severity of the symptoms (sneezing, rhinorrhea, nasal congestion, and ocular symptoms) daily on visual analog scale (VAS). We selected patients with VAS scores of >50 for any of the symptoms just before the peak pollen season (March 2 to March 8) and designated them as "poorly controlled" patients. Then, in the peak JCP season (from March 9), we conducted a randomized, double-blind, placebo-controlled study to determine whether add-on loratadine might be effective for these "poorly controlled" patients. Montelukast alone was effective, as evaluated by improvement of the VAS scores, in 95 of the 137 patients (69.3%). Add-on loratadine significantly decreased the total scores for nasal symptoms (p < 0.05), sneezing (p < 0.05), and rhinorrhea (p < 0.05) when compared with placebo. The symptoms of SAR in two of three SAR-JP patients could be controlled (VAS score[s] under 50) by prophylactic treatment with montelukast alone under the condition of mild JCP dispersal. Furthermore, the effect of add-on antihistamine on sneezing and rhinorrhea was found in selected SAR-JCP patients.  相似文献   
33.
The reliability of a loop-mediated isothermal amplification (LAMP) method for the detection of human herpesvirus 8 (HHV-8) DNA was evaluated. Although LAMP products were produced with the DNA sample extracted from BCP-1 cells, LAMP products were not produced with the DNAs from seven other human herpesviruses. The detection limit of the HHV-8 LAMP method was 100 copies of target sequence/tube. To determine whether the HHV-8 LAMP method could be used to quantify viral DNA, threshold times, which are defined as the time (in s) it takes to reach the threshold turbidity level (0.1), were measured for the amplification of serial dilutions of a DNA plasmid containing the target sequence. The standard curve possessed a correlation coefficient of 0.9428 with a slope of -84.079 and y-intercept value of 1936.2. Additionally, an attempt was made to detect viral DNA in 17 specimens collected from Kaposi's sarcomas and two cell lines obtained from primary effusion lymphomas. HHV-8 DNA was detected in 14 of the 17 Kaposi's sarcoma tissue samples and both of the primary effusion lymphoma cell lines. Viral DNA was not detected in HHV-8 LAMP-negative samples using the real-time PCR method.  相似文献   
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CONTEXT: Mouse knockout models have clearly demonstrated the critical importance of IGF-I and IGF receptor type 1 (IGF-IR) for embryonic growth as well as postnatal growth. OBJECTIVE: We hypothesized that mutations of IGF-IR gene might predispose to short stature in children born with intrauterine growth retardation (IUGR). PATIENTS: Twenty-four children with unexplained IUGR (birth weight < -1.5 SD) and short stature (<-2.0 SD) were screened for abnormalities of the IGF-IR gene. METHODS: Direct DNA sequencing was used to identify IGF-IR gene mutations. Unprocessed IGF-IR proreceptor in fibroblasts was detected by immunoblot analysis. Functions of mutated IGF-IR in fibroblasts were evaluated by IGF-I binding, and IGF-I-stimulated DNA synthesis and beta-subunit autophosphorylation. RESULTS: We found the following results: 1) a heterozygous mutation (R709Q) changing the cleavage site from Arg-Lys-Arg-Arg to Arg-Lys-Gln-Arg was identified in a 6-yr-old Japanese girl (case 1) and her mother who also had IUGR with short stature (case 2); 2) fibroblasts from case 2 contained more IGF-IR proreceptor protein (189 +/- 26% of normal) and less mature beta-subunit protein (63 +/- 12%); 3) [125I]IGF-I binding to fibroblasts from case 2 was reduced, compared with normal control (0.61 +/- 0.16 x 10(6) vs. 1.14 +/- 0.12 x 10(6) sites per cell; P < 0.05); and 4) both IGF-I-stimulated [3H]thymidine incorporation and IGF-IR beta-subunit autophosphorylation were low in fibroblasts from case 2, compared with those of control (P < 0.05). CONCLUSIONS: These findings strongly suggest that this mutation leads to failure of processing of the IGF-IR proreceptor to mature IGF-IR and causes short stature and IUGR.  相似文献   
37.
Although considerable attention has focused on obesity, insulin resistance and abnormal lipid metabolism as coronary risk factors, it remains unclear how these pathogenic factors affect the inflammatory response after myocardial ischemia-reperfusion. This study was conducted to evaluate whether these metabolic disorders exacerbate myocardial ischemia-reperfusion injury, and to determine if ischemia-reperfusion injury could be modified with the thiazolidinedione, pioglitazone. Experiments were performed in KK-Ay and C57BL/6J mice subjected to 40 min of ischemia followed by reperfusion. Infiltration of inflammatory cells in ischemic myocardium, and infarct size 3 days after reperfusion were significantly higher in KK-Ay than C57BL/6J mice (p < 0.05 and p < 0.001, respectively). Furthermore, expression of chemokines, inflammatory cytokines and extracellular matrix proteins in ischemic myocardium was significantly higher in KK-Ay than C57BL/6J mice 1 day after reperfusion. Pioglitazone treatment of KK-Ay mice for 14 days significantly reduced the accumulation of inflammatory cells in ischemic myocardium, and infarct size 3 days after reperfusion compared to vehicle treatment (p < 0.05 and p < 0.05, respectively). Pioglitazone also attenuated expression of chemokines, inflammatory cytokines and extracellular matrix proteins in ischemic myocardium 1 day after reperfusion. In vitro experiments demonstrated that tumor necrosis factor-α (TNF-α) was significantly higher in cultured peritoneal macrophages from KK-Ay than C57BL/6J mice, and pioglitazone significantly reduced TNF-α in macrophages from both types of mice. These findings suggest that metabolic disorders exacerbate ischemia-reperfusion injury as a result of overexpression of inflammatory mediators, and this effect might be improved, in part by the anti-inflammatory effects of pioglitazone.  相似文献   
38.
An 81-year-old man was admitted to the hospital with a severe sore throat and a low grade fever. A chest radiograph showed bilateral diffuse reticulonodular shadows. By fluorescent stain for mycobacteria, his sputum smear showed acid-fast bacteria. The initial polymerase chain reaction (PCR) of his sputum revealed Mycobacterium intracellulare (M. intracellulare), but not Mycobacterium tuberculosis (M. tuberculosis). However, a repeat PCR was performed because M. tuberculosis could not be ruled out due to his clinical symptoms and chest imaging. The second PCR detected both M. intracellulare and M. tuberculosis. From the standpoint of infection control, this case illustrates the possibility that M. tuberculosis could be a threat if a second PCR is not done. While PCR is a useful exam for diagnosing M. tuberculosis, it can produce false negative results. Therefore, for diagnosing tuberculosis, particularly in a case such as the present case, a second PCR, which is not normally necessary, should be done.  相似文献   
39.
We report a 67-year-old Japanese man who presented with worsening heart failure with asymptomatically transient ischemic ST-segment depression. Left ventriculography showed diffuse hypokinesis; asymptomatic coronary artery spasm was evoked by the acetylcholine provocation test. Endomyocardial biopsy exhibited hypertrophic cardiomyocytes and scattered microscopic focal myocardial necrosis with amyloid-deposition. Transient ST-segment depression improved after treatment with a calcium antagonist, but cardiac contraction was still impaired. We hypothesize that asymptomatic coronary spasm may cause irreversible cardiac damage and heart failure with amyloid-deposition; the presence or absence of coronary spasm in heart failure patients should be clarified in order to determine therapeutic strategy.  相似文献   
40.
Journal of Natural Medicines - From the methanolic extract of the leaves of Lansium domesticum, three new onoceranoid-type triterpenoids, lansium acids X–XII and a new cycloartane-type...  相似文献   
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