Imaging the paediatric lung: what does nanotechnology have to offer?

This review will provide an overview of current research into lung imaging with nanoparticles, with a focus on the use of nanoparticles as molecular imaging agents to observe pathological processes and to monitor the effectiveness of nanoparticulate drug delivery systems. Various imaging modalities together with their advantages and limitations for lung imaging will be discussed. We will also explore the range of nanoparticles used, as well as active or passive targeting of nanoparticles

Amplitude Reduction and Phase Shifts of Melatonin, Cortisol and Other Circadian Rhythms after a Gradual Advance of Sleep and Light Exposure in Humans

Background: The phase and amplitude of rhythms in physiology and behavior are generated by circadian oscillators and entrained to the 24-h day by exposure to the light-dark cycle and feedback from the sleep-wake cycle. The extent to which the phase and amplitude of multiple rhythms are similarly affected during altered timing of light exposure and the sleepwake cycle has not been fully characterized. Methodology/Principal Findings: We assessed the phase and amplitude of the rhythms of melatonin, core body temperature, cortisol, alertness, performance and sleep after a perturbation of entrainment by a gradual advance of the sleep-wake schedule (10 h in 5 days) and associated light-dark cycle in 14 healthy men. The light-dark cycle consisted either of moderate intensity ‘room ’ light (,90–150 lux) or moderate light supplemented with bright light (,10,000 lux) for 5 to 8 hours following sleep. After the advance of the sleep-wake schedule in moderate light, no significant advance of the melatonin rhythm was observed whereas, after bright light supplementation the phase advance was 8.1 h (SEM 0.7 h). Individual differences in phase shifts correlated across variables. The amplitude of the melatonin rhythm assessed under constant conditions was reduced after moderate light by 54 % (17–94%) and after bright light by 52 % (range 12–84%), as compared to the amplitude at baseline in the presence of a sleep-wake cycle. Individual differences in amplitude reduction of the melatonin rhythm correlated with the amplitude of body temperature, cortisol and alertness

Cardiosphere-derived cells suppress allogeneic lymphocytes by production of PGE2 acting via the EP4 receptor

derived cells (CDCs) are a cardiac progenitor cell population, which have been shown to possess cardiac regenerative properties and can improve heart function in a variety of cardiac diseases. Studies in large animal models have predominantly focussed on using autologous cells for safety, however allogeneic cell banks would allow for a practical, cost-effective and efficient use in a clinical setting. The aim of this work was to determine the immunomodulatory status of these cells using CDCs and lymphocytes from 5 dogs. CDCs expressed MHC I but not MHC II molecules and in mixed lymphocyte reactions demonstrated a lack of lymphocyte proliferation in response to MHC-mismatched CDCs. Furthermore, MHC-mismatched CDCs suppressed lymphocyte proliferation and activation in response to Concanavalin A. Transwell experiments demonstrated that this was predominantly due to direct cell-cell contact in addition to soluble mediators whereby CDCs produced high levels of PGE2 under inflammatory conditions. This led to down-regulation of CD25 expression on lymphocytes via the EP4 receptor. Blocking prostaglandin synthesis restored both, proliferation and activation (measured via CD25 expression) of stimulated lymphocytes. We demonstrated for the first time in a large animal model that CDCs inhibit proliferation in allo-reactive lymphocytes and have potent immunosuppressive activity mediated via PGE2

Candidate high myopia loci on chromosomes 18p and 12q do not play a major role in susceptibility to common myopia

BACKGROUND: To determine whether previously reported loci predisposing to nonsyndromic high myopia show linkage to common myopia in pedigrees from two ethnic groups: Ashkenazi Jewish and Amish. We hypothesized that these high myopia loci might exhibit allelic heterogeneity and be responsible for moderate /mild or common myopia. METHODS: Cycloplegic and manifest refraction were performed on 38 Jewish and 40 Amish families. Individuals with at least -1.00 D in each meridian of both eyes were classified as myopic. Genomic DNA was genotyped with 12 markers on chromosomes 12q21-23 and 18p11.3. Parametric and nonparametric linkage analyses were conducted to determine whether susceptibility alleles at these loci are important in families with less severe, clinical forms of myopia. RESULTS: There was no strong evidence of linkage of common myopia to these candidate regions: all two-point and multipoint heterogeneity LOD scores were < 1.0 and non-parametric linkage p-values were > 0.01. However, one Amish family showed slight evidence of linkage (LOD>1.0) on 12q; another 3 Amish families each gave LOD >1.0 on 18p; and 3 Jewish families each gave LOD >1.0 on 12q. CONCLUSIONS: Significant evidence of linkage (LOD> 3) of myopia was not found on chromosome 18p or 12q loci in these families. These results suggest that these loci do not play a major role in the causation of common myopia in our families studied

Cancer screening and preventative care among long-term cancer survivors in the United Kingdom

BACKGROUND: Long-term cancer survivors in the United Kingdom are mostly followed up in a primary care setting by their general practitioner; however, there is little research on the use of services. This study examines whether cancer survivors receive adequate screening and preventative care in UK primary care. PATIENTS AND METHODS: We identified a cohort of long-term survivors of breast, colorectal and prostate cancer with at least a 5-year survival using the General Practice Research Database, with controls matched for age, gender and practice. We compared adherence with cancer screening and the use of preventative care between cancer survivors and controls. RESULTS: The cancer survivors' cohort consisted of 18 612 breast, 5764 colorectal and 4868 prostate cancer survivors. Most cancer survivors receive cancer screening at the same levels as controls, except for breast cancer survivors who were less likely to receive a mammogram than controls (OR=0.78, 95% CI: 0.66-0.92). Long-term cancer survivors received comparable levels of influenza vaccinations and cholesterol tests, but breast (OR 0.81, 95% CI: 0.74-0.87) and prostate cancer survivors (OR=0.70, 95% CI: 0.57-0.87) were less likely to receive a blood pressure test. All survivors were more likely to receive bone densitometry. CONCLUSION: The provision and uptake of preventive care in a primary care setting in the United Kingdom is comparable between the survivors of three common cancers and those who have not had cancer. However, long-term breast cancer survivors in this cohort were less likely to receive a mammogra

Comparative maturation of cynomolgus monkey oocytes in vivo and in vitro

BACKGROUND: In vitro maturation (IVM) of oocytes followed by fertilization in vitro (IVF) and embryo transfer offers an alternative to conventional IVF treatment that minimises drug administration and avoids ovarian hyperstimulation. However, the technique is less efficient than maturation in vivo. In the present study, a non-human primate model was used to address the hypothesis that the number of oocytes is increased and their nuclear and cytoplasmic maturity after IVM are improved when maturation is initiated in vivo by priming with hCG. METHODS: Young, adult cynomolgus monkeys were given recombinant human (rh) gonadotropins to stimulate the development of multiple follicles, and oocytes were aspirated 0, 12, 24, or 36 h after injection of an ovulatory dose of rhCG. The nuclear status of oocytes was determined at the time of recovery and after culture for a total elapsed time of 40–44 hours after hCG. RESULTS: Priming with hCG significantly increased the number of oocytes harvested, especially after delaying aspiration for 24 h or longer. Nuclear maturation after the full period in culture was also enhanced by priming: 71.5, 83.6, and 94.6% of oocytes collected at 0, 12, and 24 h hCG had progressed to MII by the end of the culture period, compared to 87.8% of oocytes that were retrieved at 36 h. A large proportion of oocytes reaching the MII stage had either or both abnormal spindles (>40%) and misaligned chromosomes (>60%), judging by immunofluorescence microscopy, but these abnormalities were independent of culture time. The mitochondria were evenly distributed throughout the cytoplasm at all stages of maturation. Importantly, there was no microscopic evidence that the duration of culture had any injurious effects on the cells. CONCLUSION: In conclusion, the evidence supports this non-human primate as a model for human IVM and the practice of priming with hCG to promote developmental potential

Plasminogen binding and activation at the breast cancer cell surface: the integral role of urokinase activity

INTRODUCTION: The regulation of extracellular proteolytic activity via the plasminogen activation system is complex, involving numerous activators, inhibitors, and receptors. Previous studies on monocytic and colon cell lines suggest that plasmin pre-treatment can increase plasminogen binding, allowing the active enzyme to generate binding sites for its precursor. Other studies have shown the importance of pre-formed receptors such as annexin II heterotetramer. However, few studies have used techniques that exclusively characterise cell-surface events and these mechanisms have not been investigated at the breast cancer cell surface. METHODS: We have studied plasminogen binding to MCF-7 in which urokinase plasminogen activator receptor (uPAR) levels were upregulated by PMA (12-O-tetradecanoylphorbol-13-acetate) stimulation, allowing flexible and transient modulation of cell-surface uPA. Similar experiments were also performed using MDA-MB-231 cells, which overexpress uPAR/uPA endogenously. Using techniques that preserve cell integrity, we characterise the role of uPA as both a plasminogen receptor and activator and quantify the relative contribution of pre-formed and cryptic plasminogen receptors to plasminogen binding. RESULTS: Cell-surface plasminogen binding was significantly enhanced in the presence of elevated levels of uPA in an activity-dependent manner and was greatly attenuated in the presence of the plasmin inhibitor aprotinin. Pre-formed receptors were also found to contribute to increased plasminogen binding after PMA stimulation and to co-localise with uPA/uPAR and plasminogen. Nevertheless, a relatively modest increase in plasminogen-binding capacity coupled with an increase in uPA led to a dramatic increase in the proteolytic capacity of these cells. CONCLUSION: We show that the majority of lysine-dependent plasminogen binding to breast cancer cells is ultimately regulated by plasmin activity and is dependent on the presence of significant levels of active uPA. The existence of a proteolytic positive feedback loop in plasminogen activation has profound implications for the ability of breast cancer cells expressing high amounts of uPA to accumulate a large proteolytic capacity at the cell surface, thereby conferring invasive potential

The representation of patient experience and satisfaction in physician rating sites. A criteria-based analysis of English- and German-language sites

<p>Abstract</p> <p>Background</p> <p>Information on patient experience and satisfaction with individual physicians could play an important role for performance measures, improved health care and health literacy. Physician rating sites (PRSs) bear the potential to be a widely available source for this kind of information. However, patient experience and satisfaction are complex constructs operationalized by multiple dimensions. The way in which PRSs allow users to express and rate patient experience and satisfaction could likely influence the image of doctors in society and the self-understanding of both doctors and patients. This study examines the extent to which PRSs currently represent the constructs of patient experience and satisfaction.</p> <p>Methods</p> <p>First, a systematic review of research instruments for measuring patient experience and satisfaction was conducted. The content of these instruments was analyzed qualitatively to create a comprehensive set of dimensions for patient experience and patient satisfaction. Second, PRSs were searched for systematically in English-language and German-language search engines of Google and Yahoo. Finally, we classified every structured question asked by the different PRS using the set of dimensions of patient experience and satisfaction.</p> <p>Results</p> <p>The qualitative content analysis of the measurement instruments produced 13 dimensions of patient experience and satisfaction. We identified a total of 21 PRSs. No PRSs represented all 13 dimensions of patient satisfaction and experience with its structured questions. The 3 most trafficked English-language PRS represent between 5 and 6 dimensions and the 3 most trafficked German language PRSs between 8 and 11 dimensions The dimensions for patient experience and satisfaction most frequently represented in PRSs included diversely operationalized ones such as <it>professional competence </it>and <it>doctor-patient relationship/support</it>. However, other less complex but nevertheless important dimensions such as <it>communication skills </it>and <it>information/advice </it>were rarely represented, especially in English-language PRSs.</p> <p>Conclusions</p> <p>Concerning the potential impact of PRSs on health systems, further research is needed to show which of the current operationalizations of patient experience and satisfaction presented in our study are establishing themselves in PRSs. Independently of this factual development, the question also arises whether and to what extent health policy can and should influence the operationalization of patient experience and satisfaction in PRSs. Here, the challenge would be to produce a set of dimensions capable of consensus from among the wide range of operationalizations found by this study.</p