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991.

Objective

The aim of the study was to investigate the protective effects of Salvia miltiorrhiza (SM) against cisplatin-induced ototoxicity in guinea pigs.

Methods

Thirty-nine guinea pigs were randomly divided into 3 groups. The first group (control group) received physiologic saline by intraperitoneal (i.p.) injection for 5 days. The second group (cisplatin group) was treated with cisplatin (2 mg/kg per day, i.p. injection) for 5 days. The third group (SM group) was given SM (8 g/kg per day, i.p. injection) for 2 days and then was given SM (8 g/kg per day, i.p. injection) and cisplatin (2 mg/kg per day, i.p. injection) for 5 days. Auditory brain stem response (ABR) and cochlea blood flow measurement were used to evaluate cochlea function. The structures of cochlea were observed by light microscope, scanning electron microscope, transmission electron microscope (TEM), and immunohistochemical examination.

Results

Cisplatin could cause severe acoustic damages including significant elevation of ABR threshold, substantial losses of outer hair cells and inner hair cells, and severe damage on the stria vascularis and spiral ganglion cells (SGCs). Although in SM group, the increased tendency of threshold was milder than that in cisplatin group. The damages in cochlea and stria vascularis were also less severe than those in cisplatin group. The expression of induced nitric oxide synthase in the cochlea and SGC in SM group was lower than that in cisplatin group.

Conclusions

Salvia miltiorrhiza can significantly reduce the cisplatin-induced side effects.  相似文献   
992.
Quality of life questionnaires have been increasingly used in clinical trials to help establish the impact of medical intervention or to assess the outcome of health care services. Among disease-specific outcome measures, SNOT-22 was considered the most suitable tool for assessing chronic rhinosinusitis and patients with nasal polyps.AimsTo perform translation, cross-cultural adaptation and validation of the SNOT-22 to Brazilian Portuguese.MethodsProspective study involving eighty-nine patients with chronic rhinosinusitis or nasal polyps submitted to functional endoscopic sinus surgery, who answered the questionnaire before and after surgery. Furthermore, 113 volunteers without sinonasal disease also answered the questionnaire. Internal consistency, test-retest reliability, measure validity, responsiveness and clinical interpretability were assessed.ResultsMean preoperative, postoperative and no sinonasal disease scores were 62.39, 23.09 and 11.42, respectively (p<0.0001); showing validity and responsiveness. Internal consistency was high (Cronbach's alpha = 0.9276). Reliability was sufficiently good, considering inter-interviewers (r=0.81) and intra-interviewers within a 10 to 14 day-interval (r=0.72). Surgery effect size was 1.55. Minimally important difference was 14 points; and scores up to 10 points were considered normal.ConclusionThe Brazilian Portuguese SNOT-22 version is a valid instrument to assess patients with chronic rhinosinusitis and nasal polyps.  相似文献   
993.
目的探讨β-榄香烯(β-ELE)对人慢性髓性白血病细胞株K562细胞周期及细胞凋亡的影响及其机制。方法K562和不同浓度的β-ELE共同培养后,应用流式细胞仪技术和Hoe-chest33258/PI荧光染色法检测β-ELE对K562细胞周期及凋亡的影响,应用RT-PCR技术测定野生型p53活化片段(P21wild-type p53 activated fregmentl,P21WAF1)、Survivin mRNA水平。结果不同浓度β-ELE能使K562细胞阻滞于G1期,G1期细胞百分比增加,S期细胞百分比明显下降,呈剂量、时间依赖性,且与对照组相比差异均有统计学意义(P<0.01)。β-ELE作用于K562细胞24h,48h后,在G0/G1期前,可见明显的亚二倍体(凋亡峰),其凋亡率呈剂量、时间依赖性,与对照组比较有显著意义(P<0.01)。Hoechest33258/PI免疫荧光技术发现β-ELE能使凋亡细胞数目明显增多(P<0.01)。RT-PCR结果显示β-ELE能下调K562细胞Survivin mRNA表达,上调P21WAF1mRNA的表达(P<0.01)。结论β-ELE能够阻止细胞K562细胞从G1期向S期转换。β-ELE可以诱导K562细胞凋亡,呈剂量、时间依赖性。β-ELE导致细胞周期阻滞可能与上调P21WAF1mRNA的表达有关;促进K562细胞凋亡机制可能与下调Survivin mRNA的表达有关。随着药物浓度的增加,P21WAF1mRNA表达增加,而SurvivinmRNA表达下降。  相似文献   
994.
AIM: To evaluate glycemic excursions in adolescents with poorly controlled type 2 diabetes mellitus (DM2). METHODS: Seventeen adolescents (12 F/5 M) underwent glucose monitoring for 3 days using a continuous glucose monitoring system (CGMS). Glucose measurements were divided into periods of euglycemia, hyperglycemia, and hypoglycemia. The percentage of each period, average glucose concentration per 24 h, day and night, the number of excursions, and area under the curve (AUC) of glucose >150 mg/dl and <70 mg/dl were calculated. RESULTS: On average, patients remained in euglycemia for 28.5%, hyperglycemia for 70%, and hypoglycemia 1.3% of the total day. Hyperglycemic excursions were more frequent during the day. Hypoglycemic events were more frequent during the night. 24-h average glucose, duration of glucose >150 mg/dl, and AUC >150 mg/dl correlate with HbA1c and fructosamine to varying degrees. CONCLUSION: Continuous glucose monitoring provide valuable information on glucose excursions in adolescents with poorly controlled DM2 and may be helpful in improving metabolic control of poorly controlled adolescents with DM2.  相似文献   
995.
IntroductionBurkitt lymphoma (BL) originating in the skin and soft tissue is very rare. To our knowledge, this case of primary sporadic BL presenting as an isolated chest wall mass arising from the soft tissue in an adult may be the first report.Case ReportA previously healthy 33-year-old Caucasian man presented with a 1-month history of a painful lump over the left breast that he initially noticed as a small “pimple-like” lesion in the area. After a week, the skin lesion became larger, erythematous, and painful. At a local hospital, he underwent an incision and drainage procedure for a presumed chest wall abscess. Several days after debridement, a similar lump recurred around the incised area, which rapidly grew in size. He also started experiencing fever and chills for which he was readmitted with a diagnosis of necrotizing chest wall infection. A second debridement with excisional biopsy of the chest wall revealed atypical lymphoid cells, prompting transfer to our institution. Upon transfer, a large, gaping, erythematous and indurated wound with indistinct, thickened borders and extensive edema and necrosis of subcutaneous tissue and musculature of almost the entire left chest wall was noted. No palpable peripheral lymphadenopathy or organomegaly were observed. He underwent minimal debridement and partial excision. The histopathology revealed atypical lymphocytes with prominent nucleoli, deeply basophilic cytoplasm, and abundant lipid vacuoles in a “starry-sky” pattern. The lymphoid population was CD-20 and CD-10 positive, negative for CD-5 and BCL-2, nearly 100% Ki-67 positive, and indeterminate for light chain restriction. Molecular cytogenetic analysis revealed fusion signals with IgH/Myc t(8;14) dual fusion probe, supporting the diagnosis of BL. Staging positron emission tomography (PET)/computed tomography (CT) scan showed a large subcutaneous defect of the left hemithorax involving the dermis, subcutaneous tissue, and musculature, measuring 19.3 × 13.9 × 31.0 cm, with maximal SUV of 9.8 and an average of 6.2. No additional involved sites were seen. The bone marrow biopsy showed minimal involvement by BL and abnormal hybridization pattern for IgH/Myc t(8;14) and Epstein-Barr virus, while the peripheral blood and cerebrospinal fluid showed no involvement. HIV and hepatitis serologies were negative. Three days after surgery, chemotherapy with granulocyte colony-stimulating factor (G-CSF) support was initiated for high-risk disease. He received CODOX-M (intravenous cyclophosphamide, doxorubicin, vincristine, methotrexate; intrathecal cytarabine, methotrexate) as cycle 1 followed by IVAC (intravenous ifosfamide, etoposide, cytarabine; intrathecal methotrexate) with rituximab as cycle 2. He developed tumor lysis without end-organ damage. However, a few days after completion of cycle 2, he developed neutropenic fever and pneumonia, and died in septic shock.DiscussionPrimary chest wall tumors are uncommon. Approximately 50% are malignant, and chest wall lymphoma accounts for < 2%, with extranodal diffuse large B-cell lymphoma being the most common. Primary skin and soft tissue involvement of the chest wall in the absence of detectable lymphadenopathy and visceral disease in an adult by BL has not yet been reported. While there are isolated reports of skin and soft tissue involvement, they were in the setting of immunodeficiency state and were felt to be the result of either iatrogenic tumor seeding after nodal biopsies or local tumor invasion as a manifestation of recurrent disease. This patient's clinical presentation began with the development of an isolated rapidly enlarging chest wall mass that progressed despite surgical debridements.ConclusionThis case illustrates a primary sporadic BL originating in skin and soft tissue in an adult. Whether this case represents a BL that began in the skin and soft tissue and spread to the bone marrow, or began in the bone marrow and spread to the chest wall cannot be determined. The role of tumor debulking procedure is uncertain, although aggressive chemoimmunotherapy with central nervous system (CNS) prophylaxis is warranted as with other BL presentations.  相似文献   
996.
目的探讨金属铜配合物Cu(Ⅱ)吨酮冠醚(XCE-Cu)的体外抗肿瘤作用。方法采用噻唑蓝比色法测定XCE—Cu对卵巢癌细胞3AO、食管鳞癌细胞ECA109、肺癌细胞GLC-82、胃癌细胞SGC一7901增殖的抑制作用;应用流式细胞仪检测药物对3AO细胞周期和凋亡的影响。结果XCE—Cu呈浓度依赖性的抑制3AO、ECAl09、GLC-82、SGC-7901细胞生长,作用72h的半抑制浓度依次为4.1、8.2、15.9、8.7ug/mL,其中对3AO的抑制作用最强。作用24、48、72hXCE-Cu呈浓度、时间依赖性的抑制3AO细胞生长,作用明显强于卡铂。12.5—50ug/mL使3AO细胞G1期减少而S期和G2期增加,并剂量依赖性的诱导细胞凋亡。结论XCE—Cu在体外具有抗肿瘤作用,对3AO细胞的选择性高,其机理为阻止细胞于S期和诱导细胞调亡。  相似文献   
997.
Human coronavirus NL63 (HCoV-NL63) is a global respiratory tract pathogen; however, the epidemiology of this virus in subtropical area is not well known. To evaluate the epidemics and disease spectrum of HCoV-NL63 infection in children in Taiwan, we prospectively screened children admitted to the hospital with respiratory tract infection from May 2004 to April 2005. Every enrolled child had a nasopharyngeal aspirate (NPA) sample taken. Quantitative RT-PCR was used to detect 1b gene of HCoV-NL63. A total of 539 NPAs were collected. Seven (1.3%) were positive for HCoV-NL63. All cases were boys younger than 3 years of age and most cases occurred in autumn. Co-infection with other pathogens was observed in three cases. The most common symptoms/signs of HCoV-NL63 infection were cough, fever, and inspiratory stridor. HCoV-NL63 was the most common pathogen (14.7%) in children with croup and was the cause of three cases of croup in October. The odds ratio of croup in children infected with HCoV-NL63 was 43.4 (95% CI 8.1∼233.1). In conclusion, HCoV-NL63 is an important respiratory tract pathogen as the main cause in children admitted to the hospital in Taiwan.  相似文献   
998.

Objective

To investigate the association between myasthenia gravis (MG) and human parvovirus B19 (B19V) infection in the thymus.

Methods

The presence of human B19V DNA and protein was assessed in 138 samples—including 68 thymic hyperplasias (39 with MG), 58 thymomas (23 with MG), and 12 normal thymus tissues—using a nested polymerase chain reaction, immunohistochemistry, laser capture microdissection, and sequencing in a double-blinded manner.

Results

B19V DNA was detected mainly in thymic hyperplasia, and the positivity rate (41.18%, 28/68) was significantly higher than that in thymoma (3.45%, 2/58) (p <0.001) but not that in normal thymic tissues. Correspondingly, the positivity rate in thymic hyperplasia with MG (30.77%, 12/39) was significantly higher than that in thymoma with MG (4.35%, 1/23) (p=0.021). However, it was higher in thymic hyperplasia without MG (55.17%, 16/29) than in thymic hyperplasia with MG (30.77%, 12/39) (p=0.043). Cells in thymic hyperplasia positive for B19V VP1/VP2 protein (63.24%, 43/68) were identified mainly in ectopic germinal centres and thymic corpuscle epithelial cells, but were rare in thymomas (1.72%, 1/58) (p <0.001). Moreover, the positivity rate was significantly higher in thymic hyperplasia with MG (74.36%, 29/39) than in thymic hyperplasia without MG (48.28%, 14/29) (p=0.027).

Conclusions

To our knowledge, the present study is the first to show that human B19V infection is closely associated with thymic hyperplasia and thymic-hyperplasia-associated MG, but is not related to thymoma or thymoma-associated MG. The findings reveal a previously unrecognized aetiopathogenic mechanism of thymic-hyperplasia-associated MG, evoking numerous questions that require further investigation.  相似文献   
999.
1000.

Background

Group B Streptococcus (GBS) is an important invasive pathogen in neonates, pregnant women and the elderly. Serotype VI GBS, which has been rarely reported globally, has emerged as a significant pathogen in Asia. However, traditional serologic latex agglutination (LA) methods may fail to type isolates that lack of or low expression of CPS.

Methods

A total of 104 GBS strains were analyzed by MALDI-TOF MS. Multiplex PCR and multilocus sequence typing (MLST) were also performed to confirm their strains. The protein markers were purified with gel electrophoresis and LC-column, followed by identification with nanoLC–MS/MS analysis.

Results

Protein peak of 6251-Da was appeared in most (20/24, 92%) serotypes VI (94% ST-1 or single locus variant of ST-1), and protein peak of 6891-Da was appeared in most serotypes III (15/18, 83%) and Ib (19/23, 83%) strains. The protein peak of 6251-Da and 6891-Da were identified as CsbD family protein and UPF0337 protein gbs0600, respectively.

Conclusions

The protein peak of 6251 Da may play a role of emergence of ST-1 clone, serotype VI GBS in central Taiwan and could be useful in rapid identifying invasive serotype VI from III isolates, which is hardly achieved by LA.  相似文献   
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