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1.

Background

Advanced low-grade ovarian carcinoma (LGOC) is difficult to treat. In several studies, high estrogen receptor (ER) protein expression was observed in patients with LGOC, which suggests that antihormonal therapy (AHT) is a treatment option. However, only a subgroup of patients respond to AHT, and this response cannot be adequately predicted by currently used immunohistochemistry (IHC). A possible explanation is that IHC only takes the ligand, but not the activity, of the whole signal transduction pathway (STP) into account. Therefore, in this study, the authors assessed whether functional STP activity can be an alternative tool to predict response to AHT in LGOC.

Methods

Tumor tissue samples were obtained from patients with primary or recurrent LGOC who subsequently received AHT. Histoscores of ER and progesterone receptor (PR) were determined. In addition, STP activity of the ER STP and of six other STPs known to play a role in ovarian cancer was assessed and compared with the STP activity of healthy postmenopausal fallopian tube epithelium.

Results

Patients who had normal ER STP activity had a progression-free survival (PFS) of 16.1 months. This was significantly shorter in patients who had low and very high ER STP activity, with a median PFS of 6.0 and 2.1 months, respectively (p < .001). Unlike ER histoscores, PR histoscores were strongly correlated to the ER STP activity and thus to PFS.

Conclusions

Aberrant low and very high functional ER STP activity and low PR histoscores in patients with LGOC indicate decreased response to AHT. ER IHC is not representative of functional ER STP activity and is not related to PFS.  相似文献   
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Circadian rhythm disorders have been classically associated with disorders of abnormal timing of the sleep–wake cycle, however circadian dysfunction can play a role in a wide range of pathology, ranging from the increased risk for cardiometabolic disease and malignancy in shift workers, prompting the need for a new field focused on the larger concept of circadian medicine. The relationship between circadian disruption and human health is bidirectional, with changes in circadian amplitude often preceding the classical symptoms of neurodegenerative disorders. As our understanding of the importance of circadian dysfunction in disease grows, we need to develop better clinical techniques for identifying circadian rhythms and also develop circadian based strategies for disease management. Overall this review highlights the need to bring the concept of time to all aspects of medicine, emphasizing circadian medicine as a prime example of both personalized and precision medicine.  相似文献   
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ObjectiveMental health problems affect up to 20% of women during pregnancy and the postpartum period. This study aimed to describe the mental health services and resources accessed by women with perinatal mental health problems (PMH) and to identify their unmet mental health care needs and preferences for support, as well as the barriers to accessing this support.MethodsParticipants were 18 years of age or older and spoke English or French. Consent was obtained 24 hours after delivery (T0) to screen for symptoms of depression and anxiety at 2 weeks postpartum (T1) using the Edinburgh Postnatal Depression Scale (EPDS) and the Generalized Anxiety Disorder Scale (GAD-7). Women with a positive screen (EPDS ≥10 or GAD-7 ≥10) were sent informational resources and were followed-up by telephone at 4 months postpartum (T2) to determine their use of these and other resources, their unmet needs, and their preferences for other resources or services.ResultsSeventy-three out of 344 participants (21.2%) screened positive, of whom 57 (78%) completed the T2 interview. Of those interviewed, 28% had used the informational resources provided by the study. Although 25% had consulted a health professional for mental health care, 37% had unmet mental health care needs. Preferences for additional support included web-based resources (30%), telephone support (28%), and booklets (25%). Lack of time (38%) and lack of childcare (23%) were the main barriers to seeking help.ConclusionsWeb- and telephone-based approaches have the potential to address the most common barriers to access support for women experiencing perinatal mental health problems.  相似文献   
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Nicotine stimulates osteoclast resorption in a porcine marrow cell model   总被引:2,自引:0,他引:2  
BACKGROUND: Combustible tobacco use is generally linked with accelerated periodontal bone loss and diminished post-surgical wound healing; however, the pathogenesis of this process at the cellular level remains unclear. Nicotine is known to affect human gingival fibroblast orientation, attachment, and beta1 integrin expression, yet little is known about its effects on osteoclasts, the cells most responsible for bone resorption. The purpose of this study was to determine the effects of physiologically relevant nicotine levels on porcine osteoclast function as measured by resorption of calcium phosphate. METHODS: Pure nicotine was diluted in medium to the following concentrations: 0.03 microM, 0.15 microM, 0.30 microM, 0.60 microM, and 1.50 microM. Porcine osteoclasts were seeded onto calcium phosphate multi-test slides and incubated at 37 degrees C with half media changes every 24 hours. Cells received 0, 0.15, 0.30, 0.60, and 1.50 microM nicotine, or 25 nM parathyroid hormone (PTH). Osteoclast resorption was quantified by measuring the resorbed surface area of the calcium phosphate substrate. RESULTS: Osteoclast cultures resorbed bone slices and calcium phosphate substrate. All nicotine concentrations and PTH resulted in statistically significantly greater mean percent resorptions than the control group (P < 0.05). However, no statistical difference was found between the various nicotine doses or PTH. The number of osteoclasts increased in a linear relationship to the increasing nicotine concentrations; however, no correlation was found between osteoclast number and the amount of resorption. CONCLUSIONS: Nicotine is non-toxic to osteoclasts at the clinically relevant levels tested. Nicotine appears to stimulate osteoclast differentiation and resorption of calcium phosphate, the major component of bone. Nicotine-modulated osteoclast stimulation may, in part, explain the increased rapidity of periodontal bone loss and refractory disease incidence in smokers.  相似文献   
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