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101.
The mitotic kinase Aurora A is an important therapeutic target for cancer therapy. This study evaluated new mechanism-based pharmacodynamic biomarkers in cancer patients in two phase I studies of MLN8054, a small-molecule inhibitor of Aurora A kinase. Patients with advanced solid tumors received MLN8054 orally for 7 consecutive days in escalating dose cohorts, with skin and tumor biopsies obtained before and after dosing. Skin biopsies were evaluated for increased mitotic cells within the basal epithelium. Tumor biopsies were assessed for accumulation of mitotic cells within proliferative tumor regions. Several patients in the highest dose cohorts showed marked increases in the skin mitotic index after dosing. Although some tumors exhibited increases in mitotic cells after dosing, others displayed decreases, a variable outcome consistent with dual mechanisms of mitotic arrest and mitotic slippage induced by antimitotics in tumors. To provide a clearer picture, mitotic cell chromosome alignment and spindle bipolarity, new biomarkers of Aurora A inhibition that act independently of mitotic arrest or slippage, were assessed in the tumor biopsies. Several patients, primarily in the highest dose cohorts, had marked decreases in the percentage of mitotic cells with aligned chromosomes and bipolar spindles after dosing. Evidence existed for an exposure-effect relationship for mitotic cells with defects in chromosome alignment and spindle bipolarity that indicated a biologically active dose range. Outcomes of pharmacodynamic assays from skin and tumor biopsies were concordant in several patients. Together, these new pharmacodynamic assays provide evidence for Aurora A inhibition by MLN8054 in patient skin and tumor tissues.  相似文献   
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AimThe aim of this is to evaluate the prevalence and location of the accessory mental foramen (AMF) in a Saudi population using cone-beam computed tomography (CBCT).MethodologyCBCT data were retrieved from two dental facilities at two universities located in two different cities and filtered over a period of four years. The scans were aligned when the AMF was noticed, and then the size of both the AMF and mental foramen (MF), its location, and the distance from the AMF to the MF were recorded. The AMF measurements were compared between males and females and between the two sides of the mandible.ResultsIn total, 603 CBCT scans were investigated. The percentage of scans with an AMF was 9.95% (n = 60), and AMFs were almost equally distributed on both sides. Only four cases (0.66%) of a second AMF were detected among the scans. The MFs on both sides were significantly larger in males than in females (P > 0.05), but they showed no differences in the sizes of the AMFs. The AMFs were most commonly located inferior and posterior to the MF. The distance between the MF and AMF ranged from 2.32 to 5 mm.ConclusionsThe prevalence of the AMF in this Saudi population was 9.95%, and it was significantly more prevalent in males than in females. Its proximity to the MF makes it clinically important to conduct proper detailed planning prior to performing any procedure that might risk the vital structures.  相似文献   
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Purpose : This study aimed to determine if the use of gabapentin is more efficacious than a stabilization splint with regard to the intensity of masseter muscle contractions and/or sleep quality for patients experiencing sleep bruxism (SB). Materials and Methods : Twenty patients with SB participated in this clinical study. They were randomly divided into two treatment groups: stabilization splint group (n = 10) and gabapentin group (n = 10). The first polysomnographic examination was performed before the beginning of the experiment for all the participants. At the end of a 2‐month period of stabilization splint therapy or gabapentin usage, a second polysomnographic recording was made. Results : Statistically significant reductions in the number of SB episodes per hour and per night, bruxism time index, total duration of SB episodes per night and number of SB episodes in stages NR I and NR II (p < 0.05) were observed in both groups after treatment. Both treatments significantly reduced the mean intensity of masseter muscle contractions during SB episodes. Moreover, the participants treated with gabapentin showed a significant improvement in total sleep time, slow wave sleep (stage III), and sleep efficiency (p < 0.05). Conclusions : Gabapentin could be an effective treatment modality in SBs, especially in those with poor sleep quality.  相似文献   
105.
Aim: To provide demographics and pathology of cancer of the uterine corpus in Karachi. Methodology: Data for 66 incident cases of cancer corpus uteri, ICD-10 category C54-5 registered at the Karachi Cancer Registry, for Karachi South, during a 3 year period, 1st January, 1995 to 31st December 1997 were reviewed. Results: Cancer uterine corpus (1995-97) was the sixth most common malignancy, following breast, oral cavity, ovary, esophagus and cervix. The age standardized incidence rate (ASR) world and crude incidence rate (CIR) per 100,000 were 6.4 (4.73 to 8.01) and 2.9 (2.18 to 3.57). The mean age was 53.7 years (SD 15.6; range 6-90 years). Fifty eight cases were endometrial carcinoma with ASR world and CIR per 100,000 of 5.77 (4.20 to 7.33) and 2.53 (1.88 to 3.18) respectively. Sarcomas comprised 6% of the cases. Approximately a third of the females (28.8%) were below 50 years of age. The age-specific curves showed a gradual increase from the fourth till the seventh decade, followed by an actual apparent decrease in risk after 70 years. Peak incidence was observed in the 65-69 year age group. Presenting symptoms were post-menopausal bleeding (86.4%) and purulent discharge (4%). Associated pathologies included adenomyosis, adenomatous hyperplasia (12% each) or leiomyoma (8%). Associated clinical conditions were diabetes mellitus and hypertension (4% each). The majority of the cases presented as well differentiated (39.4%), localized (59.1%) lesions. Conclusion: The incidence of cancer corpus uteri in Karachi South reflects a moderate risk population, predominantly middle aged with a higher socio-economic status. On the average the malignancy is observed a decade earlier then reported elsewhere. This calls for in-depth investigation of risk factors and identification of underlying etiology.  相似文献   
106.
Saffron (dried stigmas of Crocus sativus L.) has been used as a spice, food colorant and medicinal plant for millennia. In this study cytotoxic effect of saffron extract was evaluated in HepG2 and HeLa cell lines. Meanwhile role of apoptosis and ROS were explored. Malignant and non-malignant cells (L929) were cultured in DMEM medium and incubated with different concentrations of ethanolic saffron extract. Cell viability was quantitated by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flow cytometry (sub-G1 peak). ROS was measured using DCF-DA by flow cytometry analysis. Saffron could decrease cell viability in malignant cells as a concentration and time-dependent manner. The IC50 values against HeLa and HepG2 were determined 800 and 950 μg/ml after 48 h, respectively. Saffron induced a sub-G1 peak in flow cytometry histogram of treated cells compared to control indicating apoptotic cell death is involved in saffron toxicity. This toxicity was also independent of ROS production. It might be concluded that saffron could cause cell death in HeLa and HepG2 cells, in which apoptosis or programmed cell death plays an important role. Saffron could be also considered as a promising chemotherapeutic agent in cancer treatment in future.  相似文献   
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The rare association of Addison's disease and autoimmune hypothyroidism (Schmidt's syndrome) occurred during two pregnancies in the same woman. The association of Addison's disease and pregnancy is serious, and affected patients should be followed closely for electrolyte homeostasis.  相似文献   
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