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101.
s-Thalidomide has proven efficacy in multiple myeloma. Although it has both antiangiogenic and pro-apoptotic effects, its primary mode of therapeutic action remains unclear. We have investigated the changes to the expression of genes involved with these cellular processes following culture with s-thalidomide in the U266 MM cell line. Cells were cultured with s-thalidomide (0-1000 microM), and cell parameters, including apoptosis, were assessed on day 3. RNA was extracted from cells cultured for 24 h at the IC(50) concentration of s-thalidomide, and changes to gene expression were investigated by microarray methodologies. A reduction in cell viability was observed in U266 cells cultured with s-thalidomide (IC(50): 362 microM), which were mirrored by significant increases in apoptosis (for example, 200 microM on day 3: 40.3+/-3.1% vs. 3.2+/-0.4% on day 0; P<0.001). There were changes in the expression profile of genes involved in angiogenesis and apoptosis, but the changes were most dramatic in the apoptotic genes. In particular, the expression of I-kappaB kinase was decreased by two-fold, which was associated with a four-fold decrease in NF-kappaB expression. These data correlated with immunoblotting analyses, which showed significant increases in I-kappaB protein levels and decreased NF-kappaB activity. Additionally, the Bax : Bcl-2 ratio was significantly increased. Our data suggest that both angiogenic and apoptotic genes and proteins are affected by s-thalidomide. Additionally, a dramatic decrease in Bcl-2 expression with s-thalidomide suggests a possible enhancement of cytotoxic effect if combined with other cytotoxic agents.  相似文献   
102.

Background  

Attention-deficit hyperactivity disorder is an early-onset, clinically heterogenous disorder of inattention, hyperactivity, and impulsiveness. The diagnosis and treatment of attention-deficit hyperactivity disorder continues to raise controversy, and, there is also an increase in treatment options. In this 6-week double blind, placebo controlled-trial, we assessed the effects of zinc plus methylphenidate in the treatment of children with attention deficit hyperactivity disorder. To the best of our knowledge, this study is the first double blind and placebo controlled clinical trial assessing the adjunctive role of zinc in ADHD.  相似文献   
103.
A 32-year-old woman presented with an abrupt, localized loss of scalp hair that occurred on the previous day. Her nails, skin, and mucosae were normal. On the vertex of the scalp, there was a circular patch of alopecia; the hairs were broken at approximately equal lengths above the skin surface. Several erythematous macules were seen in the affected area, but scale, twisted hair, and exclamation-mark hairs were not present. Further examination revealed the presence of ants on the scalp. This patient is one of several referred to our department presenting with hair loss associated with hair-cutter ant invasion.  相似文献   
104.
BACKGROUND: In Iran, there is insufficient information on the efficacy of Helicobacter pylori eradication regimens shorter than 10 days. This study aims at assessing the efficacy of 4- and 7-day H. pylori eradication regimens in a high-incidence area of gastric cancer in Iran. METHODS: Subjects with an endoscopic diagnosis of gastritis, positive urease test, and a histological diagnosis of chronic gastritis were enrolled. Patients were randomly assigned to one of three groups: AOC7 (1000 mg amoxicillin, 20 mg omeprazole, and 500 mg clarithromycin twice daily for 7 days), FOT4 (200 mg furazolidone, 20 mg omeprazole, and 500 mg tetracycline twice daily for 4 days) and FOT7 (the same treatment as the FOT4 group but for 7 days). Sensitivity to these antibiotics was determined in all isolates recovered from culture. The efficacy of eradication was assessed 8 weeks after the end-of-treatment by the 14C-urea breath test. RESULTS: One hundred and twenty-eight patients were enrolled in the study. Culture was positive for 84 patients and none of these were resistant to amoxicillin, tetracycline or furazolidone, 1.2% were resistant to clarithromycin and 32.1% to metronidazole. Forty-five, 41 and 42 patients were randomly allocated to the AOC7, FOT4, and FOT7 groups, respectively. The intention-to-treat eradication rates were 35.5, 17.1, and 23.8% for the AOC7, FOT4, and FOT7 groups, respectively. CONCLUSION: Treatment regimens of 4 or 7 days are unacceptable for H. pylori infection in Iran, even in the presence of a favorable sensitivity profile.  相似文献   
105.
PURPOSE: Weakening of the inferior oblique muscle is the procedure of primary importance in patients with superior oblique palsy, Knapp's Classes I and III. In this study, the effectiveness of anterior transposition of the inferior oblique muscle in treatment of these patients was evaluated. METHODS: Sixteen patients with superior oblique palsy, Knapp's Classes I and III, underwent anterior transposition of the inferior oblique muscle. The tip of the disinserted muscle was sutured to the sclera, parallel, and adjacent to the lateral border of the inferior rectus muscle insertion. The prism and alternate cover test measurements were made in all cardinal positions of gaze before and 6 months after surgery. RESULTS: The mean reduction of hyperdeviation was 15 prism diopters (PD) in the primary position, 23.4 PD in adduction, 26.65 PD in elevation and adduction, and 18.63 PD in depression and adduction. There was no hypotropia in the primary position. Mild limitation of upgaze has occurred in 3 of these patients, and mild fullness of the lower lid was developed by 25%. Postoperative hyperdeviation in the primary position was 5 PD or less in 15 out of 16 patients. CONCLUSIONS: The anterior transposition of the inferior oblique muscle is very effective in eliminating hyperdeviation in patients with superior oblique palsy, Knapp's Classes I and III. Up to 25 PD reduction of hyperdeviation in the primary position can be achieved. If this type of anterior transposition is used, primary position hypotropia or marked limitation of upgaze possibly will not occur.  相似文献   
106.
107.
Trefoil peptides (TFFs) are now considered as scatter factors, proinvasive and angiogenic agents acting through cyclooxygenase-2 (COX-2)- and thromboxane A2 receptor (TXA2-R)-dependent signaling pathways. As expression and activation levels of the epidermal growth factor receptor (EGFR) predict the metastatic potential of human colorectal cancers, the purpose of this study was to establish whether the EGF receptor tyrosine kinase (EGFR-TK) contributes to cellular invasion induced by TFFs in kidney and colonic cancer cells. Both the dominant negative form of the EGFR (HER-CD533) and the EGFR-TK inhibitor ZD1839 (Iressa) abrogated cellular invasion induced by pS2, spasmolytic polypeptide (SP) and the src oncogene, but not by ITF and the TXA2-R. Similarly, EGFR-TK inhibition by ZD1839 reversed the invasive phenotype promoted by the constitutively activated form of the EGFR (EGFRvIII) and the EGFR agonists transforming growth factor alpha (TGFalpha), amphiregulin and EGF. We also provide evidence that TFFs, EGFRvIII, and TGFalpha trigger common proinvasive pathways using the PI3'-kinase and Rho/Rho- kinase cascades. These findings identify the EGFR-TK as a key signaling element for pS2- and SP-mediated cellular invasion. It is concluded that although pS2, SP and ITF belong to the same family of inflammation- and cancer-associated regulatory peptides, they do not control identical signaling networks.  相似文献   
108.
A series of N-[5-(1-methyl-5-nitro-2-imidazolyl)-1,3,4-thiadiazole-2-yl] and N-[5-(nitrophenyl)-1,3,4-thiadiazole-2-yl] piperazinyl quinolone derivatives (5a-c and 5d-l) were synthesized and evaluated for in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria. The antibacterial data revealed that all nitroimidazole derivatives (5a-c) showed interesting activity against tested Gram-positive bacteria (minimum inhibitory concentration, MIC=0.008-0.03 microg/ml) while they did not show good activity against Gram-negative organisms. Despite the significant activity of nitroimidazole series, all nitrophenyl analogues (5d-l) were inactive against both Gram-positive and Gram-negative bacteria. Among all of the tested compounds, 5a (ciprofloxacin derivative in nitroimidazole series) exhibited excellent activity against Staphylococcus aureus and Staphylococcus epidermidis (MIC=0.008 microg/ml).  相似文献   
109.
A series of alkyl alpha-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-ylthio]acetic acid esters 6a-e were synthesized and evaluated for in vitro antituberculosis activity against Mycobacterium tuberculosis strain H(37)Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. The antituberculosis data indicated that methyl, propyl, buthyl and benzyl esters showed a significant in vitro antimycobacterium tuberculosis activity (MIC=0.39-0.78 microg/ml) and the ethyl analogue did not show a good activity (MIC>6.25 microg/ml, %inhibition=58). The most active compound of the series was n-propyl alpha-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-ylthio]acetate (6c) with MIC value of 0.39 microg/ml.  相似文献   
110.
A series of N-[2-(2-furyl)-2-oxoethyl], N-[2-(2-furyl)-2-oxyiminoethyl], N-[2-oxo-2-(2-thienyl)ethyl] and N-[2-oxyimino-2-(2-thienyl)ethyl] piperazinyl quinolones (1a-h; 2a-h) were evaluated for antituberculosis activity against M. tuberculosis H37Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. Our results indicated that compounds 1a, 1e and 1g were efficient antimycobacterial agents showing MIC values ranging from 0.78 to 6.25 microg/ml. In general, ciprofloxacin derivatives were more active than norfloxacin derivatives and the oxime analogues were less active than corresponding ketones. Active compounds (1a, 1e and 1g) were also screened by serial dilution to assess toxicity to VERO cell line. The cytotoxicity of tested compounds indicated that compound 1a was the less toxic compound (IC50 > 62.5 microg/ml). This compound was tested for efficacy in vitro in TB-infected macrophage model (EC90 = 3.25 microg/ml).  相似文献   
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