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61.
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Classical chemotherapeutic anti-cancer treatments induce cell death through DNA damage by taking advantage of the proliferative behaviour of cancer cells. The more recent approach of targeted therapy (usually protein-targeted) has led to many treatments that are currently available or are under development, all of which are designed to strike at the critical driving forces of cancer cells. The interaction of the cancer cells with their microenvironment is one of these fundamental features of neoplasms that could be targeted in such cancer treatments. Haematological and solid tumour cells interact with their microenvironment through membrane chemokine receptors and their corresponding ligands, which are expressed in the tumour microenvironment. Important representatives of this system are the chemokine ligand CXCL12 and its receptor chemokine receptor 4 (CXCR4). This interaction can be disrupted by CXCR4 antagonists, and this concept is being used clinically to harvest haematopoietic stem/progenitor cells from bone marrow. CXCR4 and CXCL12 also have roles in tumour growth and metastasis, and more recently their roles in cancer cell-tumour microenvironment interaction and angiogenesis have been studied. Our review focuses on these roles and summarises strategies for treating cancer by disrupting this interaction with special emphasis on the CXCR4/CXCL12 axis. Finally, we discuss ongoing clinical trials with several classes of CXCR4 inhibitors, and their potential additive value for patients with a (therapy resistant) malignancy by sensitising cancer cells to conventional therapy.  相似文献   
63.
It has been argued, based on a limited amount of research data, that patient participation in decision-making regarding surgery, results not only in more patient satisfaction, but also in better surgery outcomes. Especially in a procedure such as hysterectomy, with far-reaching consequences and many potential side effects, it may therefore be relevant to promote an active role of the patient in the decision-making process. The article identifies contextual elements that might promote this active role. Subsequently a model of participative, informed decision-making is outlined. The model entails that clinical guidelines should be adjusted to the particular situation at hand and that patients should be fully informed about hysterectomy-involved risks. An overview of the various guidelines and risks is provided. Proper counseling in the decision-making phase as well as in the post-hysterectomy period is advocated. Throughout the article attention is paid to documented and undocumented ethnic differences regarding various aspects of hysterectomy, particularly differences in patient participation around the world.  相似文献   
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Introduction

Delirium is associated with impaired outcome, but it is unclear whether this relationship is limited to in-hospital outcomes and whether this relationship is independent of the severity of underlying conditions. The aim of this study was to investigate the association between delirium in the intensive care unit (ICU) and long-term mortality, self-reported health-related quality of life (HRQoL), and self-reported problems with cognitive functioning in survivors of critical illness, taking severity of illness at baseline and throughout ICU stay into account.

Methods

A prospective cohort study was conducted. We included patients who survived an ICU stay of at least a day; exclusions were neurocritical care patients and patients who sustained deep sedation during the entire ICU stay. Delirium was assessed twice daily with the Confusion Assessment Method for the ICU (CAM-ICU) and additionally, patients who received haloperidol were considered delirious. Twelve months after ICU admission, data on mortality were obtained and HRQoL and cognitive functioning were measured with the European Quality of Life – Six dimensions self-classifier (EQ-6D). Regression analyses were used to assess the associations between delirium and the outcome measures adjusted for gender, type of admission, the Acute Physiology And Chronic Health Evaluation IV (APACHE IV) score, and the cumulative Sequential Organ Failure Assessment (SOFA) score throughout ICU stay.

Results

Of 1101 survivors of critical illness, 412 persons (37%) had been delirious during ICU stay, and 198 (18%) died within twelve months. When correcting for confounders, no significant association between delirium and long-term mortality was found (hazard ratio: 1.26; 95% confidence interval (CI) 0.93 to 1.71). In multivariable analysis, delirium was not associated with HRQoL either (regression coefficient: -0.04; 95% CI -0.10 to 0.01). Yet, delirium remained associated with mild and severe problems with cognitive functioning in multivariable analysis (odds ratios: 2.41; 95% CI 1.57 to 3.69 and 3.10; 95% CI 1.10 to 8.74, respectively).

Conclusions

In this group of survivors of critical illness, delirium during ICU stay was not associated with long-term mortality or HRQoL after adjusting for confounding, including severity of illness throughout ICU stay. In contrast, delirium appears to be an independent risk factor for long-term self-reported problems with cognitive functioning.  相似文献   
66.
PURPOSE: The effect of methylphenidate (MPH) on inhibitory control as assessed by the stop task in children with attention-deficit/hyperactivity disorder (ADHD) could be influenced by task difficulty and may be mediated by attention. SUBJECTS AND METHODS: Fifteen children with ADHD performed the stop and the change task after placebo, 0.5 and 1.0 mg/kg MPH in a within-subject design. RESULTS: Linear-trend analysis showed a similar effect of MPH in both tasks and a stronger effect for inhibitory control than for attention. Furthermore, a correlation was found between blood serum metabolites of norepinephrine and dopamine for attentional measures and inhibitory control measures, respectively. DISCUSSION AND CONCLUSION: In children with ADHD MPH could act primarily on inhibitory control, and is not influenced by task difficulty. Also, attention and inhibitory control could have differential pharmacological profiles.  相似文献   
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68.

Objectives

To document the prevalence of impaired glucose tolerance (IGT) and undiagnosed diabetes mellitus (DM) and to identify factors associated with undiagnosed DM in people living with HIV (PLWH).

Methods

Cross-sectional study performed at Ndlovu Medical Center, Limpopo, South Africa including PLWH aged ≥18 years. Between August and November 2017, 356 HIV-positive participants were included. Information was collected on socio-demographics, DM symptoms and risk factors for DM. IGT and DM were diagnosed using random plasma glucose and/or HbA1c. Factors associated with undiagnosed DM were assessed by comparing participants with newly diagnosed DM to participants without DM.

Results

IGT was diagnosed in 172 (48.3%) participants. Twenty-nine (8.1%) participants met the definition of DM, of whom 17 (58.6%) were newly diagnosed. Compared to participants without DM, participants with DM were on average 5 years older, were more likely to have a positive family history for DM, were less physically active and had higher systolic blood pressure, body mass index and waist circumference. Factors associated with undiagnosed DM included age ≥45 years (odds ratio [OR] = 3.59) and physical inactivity (OR = 3.17).

Conclusions

The prevalence of IGT and DM among PLWH is high and more than half of DM cases were undiagnosed. Regular screening for DM in PLWH is recommended, especially in an ageing population with additional cardiovascular disease risk factors.  相似文献   
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Specific diagnostic markers are the key to effective diagnosis and treatment of inborn errors of metabolism (IEM). Untargeted metabolomics allows for the identification of potential novel diagnostic biomarkers. Current separation techniques coupled to high-resolution mass spectrometry provide a powerful tool for structural elucidation of unknown compounds in complex biological matrices. This is a proof-of-concept study testing this methodology to determine the molecular structure of as yet uncharacterized m/z signals that were significantly increased in plasma samples from patients with phenylketonuria and 3-hydroxy-3-methylglutaryl-CoA lyase deficiency. A hybrid linear ion trap-orbitrap high resolution mass spectrometer, capable of multistage fragmentation, was used to acquire accurate masses and product ion spectra of the uncharacterized m/z signals. In order to determine the molecular structures, spectral databases were searched and fragmentation prediction software was used. This approach enabled structural elucidation of novel compounds potentially useful as biomarkers in diagnostics and follow-up of IEM patients. Two new conjugates, glutamyl-glutamyl-phenylalanine and phenylalanine-hexose, were identified in plasma of phenylketonuria patients. These novel markers showed high inter-patient variation and did not correlate to phenylalanine levels, illustrating their potential added value for follow-up. As novel biomarkers for 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, three positional isomers of 3-methylglutaconyl carnitine could be detected in patient plasma. Our results highlight the applicability of current accurate mass multistage fragmentation techniques for structural elucidation of unknown metabolites in human biofluids, offering an unprecedented opportunity to gain further biochemical insights in known inborn errors of metabolism by enabling high confidence identification of novel biomarkers.  相似文献   
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