14 research outputs found

    Conjugation to the Cell-Penetrating Peptide TAT Potentiates the Photodynamic Effect of Carboxytetramethylrhodamine

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    Cell-penetrating peptides (CPPs) can transport macromolecular cargos into live cells. However, the cellular delivery efficiency of these reagents is often suboptimal because CPP-cargo conjugates typically remain trapped inside endosomes. Interestingly, irradiation of fluorescently labeled CPPs with light increases the release of the peptide and its cargos into the cytosol. However, the mechanism of this phenomenon is not clear. Here we investigate the molecular basis of the photo-induced endosomolytic activity of the prototypical CPPs TAT labeled to the fluorophore 5(6)-carboxytetramethylrhodamine (TMR).We report that TMR-TAT acts as a photosensitizer that can destroy membranes. TMR-TAT escapes from endosomes after exposure to moderate light doses. However, this is also accompanied by loss of plasma membrane integrity, membrane blebbing, and cell-death. In addition, the peptide causes the destruction of cells when applied extracellularly and also triggers the photohemolysis of red blood cells. These photolytic and photocytotoxic effects were inhibited by hydrophobic singlet oxygen quenchers but not by hydrophilic quenchers.Together, these results suggest that TAT can convert an innocuous fluorophore such as TMR into a potent photolytic agent. This effect involves the targeting of the fluorophore to cellular membranes and the production of singlet oxygen within the hydrophobic environment of the membranes. Our findings may be relevant for the design of reagents with photo-induced endosomolytic activity. The photocytotoxicity exhibited by TMR-TAT also suggests that CPP-chromophore conjugates could aid the development of novel Photodynamic Therapy agents

    Pregnancy related anxiety and general anxious or depressed mood and the choice for birth setting:A secondary data-analysis of the DELIVER study

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    BACKGROUND: In several developed countries women with a low risk of complications during pregnancy and childbirth can make choices regarding place of birth. In the Netherlands, these women receive midwife-led care and can choose between a home or hospital birth. The declining rate of midwife-led home births alongside the recent debate on safety of home births in the Netherlands, however, suggest an association of choice of birth place with psychological factors related to safety and risk perception. In this study associations of pregnancy related anxiety and general anxious or depressed mood with (changes in) planned place of birth were explored in low risk women in midwife-led care until the start of labour. METHODS: Data (n = 2854 low risk women in midwife-led care at the onset of labour) were selected from the prospective multicenter DELIVER study. Women completed the Pregnancy Related Anxiety Questionnaire-Revised (PRAQ-R) to assess pregnancy related anxiety and the EuroQol-6D (EQ-6D) for an anxious and/or depressed mood. RESULTS: A high PRAQ-R score was associated with planned hospital birth in nulliparous (aOR 1.92; 95% CI 1.32–2.81) and parous women (aOR 2.08; 95% CI 1.55–2.80). An anxious or depressed mood was associated with planned hospital birth (aOR 1.58; 95% CI 1.20–2.08) and with being undecided (aOR 1.99; 95% CI 1.23–2.99) in parous women only. The majority of women did not change their planned place of birth. Changing from an initially planned home birth to a hospital birth later in pregnancy was, however, associated with becoming anxious or depressed after 35 weeks gestation in nulliparous women (aOR 4.17; 95% CI 1.35–12.89) and with pregnancy related anxiety at 20 weeks gestation in parous women (aOR 3.91; 95% CI 1.32–11.61). CONCLUSION: Low risk women who planned hospital birth (or who were undecided) more often reported pregnancy related anxiety or an anxious or depressed mood. Women who changed from home to hospital birth during pregnancy more often reported pregnancy related anxiety or an anxious or depressed mood in late pregnancy. Anxiety should be adequately addressed in the process of informed decision-making regarding planned place of birth in low risk women

    Primary prostatic haemangiosarcoma causing severe haematuria in a dog

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    A 10-year-old, entire, male, mixed-breed dog was presented for severe haematuria and stranguria. Ultrasound revealed a large intraluminal urinary bladder blood clot and a prostatic space-occupying lesion. Invasion of the lesion into the prostatic urethra was detected ultrasonographically during compression of the urinary bladder. Post-mortem examination revealed primary prostatic haemangiosarcoma infiltrating the urethra. Haemangiosarcoma should be considered as a rare cause of prostatic mass lesions, haematuria or lower urinary tract signs in dogs

    The BepiColombo Laser Altimeter

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    The BepiColombo Laser Altimeter (BELA) is the first European laser altimeter constructed for interplanetary flight. BELA uses a 50 mJ pulsed Nd:YAG laser operating at 10 Hz with a 20 cm aperture receiver to perform the ranging. The instrument also uses a digital approach for range detection and pulse analysis. The ranging accuracy is expected to be better than 2 metres and ∼20 cm in optimum conditions. With the given, only slightly elliptical, orbit, BELA should return a consistent data set for the most if not all of the planet. The instrument is required to function in an extreme environment with the thermal issues being particularly demanding. Novel solutions have been taken to resolve these issues. BELA is described in detail and its predicted performance outlined on the basis of pre-flight testing

    Study protocol for reducing childbirth fear: a midwife-led psycho-education intervention

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    Background: Childbirth fear has received considerable attention in Scandinavian countries, and the United Kingdom, but not in Australia. For first-time mothers, fear is often linked to a perceived lack of control and disbelief in the body's ability to give birth safely, whereas multiparous women may be fearful as a result of previous negative and/or traumatic birth experiences. There have been few well-designed intervention studies that test interventions to address women's childbirth fear, support normal birth, and diminish the possibility of a negative birth experience. Methods/design: Pregnant women in their second trimester of pregnancy will be recruited and screened from antenatal clinics in Queensland, Australia. Women reporting high childbirth fear will be randomly allocated to the intervention or control group. The psycho-educational intervention is offered by midwives over the telephone at 24 and 34\ua0weeks of pregnancy. The intervention aims to review birth expectations, work through distressing elements of childbirth, discuss strategies to develop support networks, affirm that negative childbirth events can be managed and develop a birth plan. Women in the control group will receive standard care offered by the public funded maternity services in Australia. All women will receive an information booklet on childbirth choices. Data will be collected at recruitment during the second trimester, 36\ua0weeks of pregnancy, and 4-6\ua0weeks after birth. Discussion: This study aims to test the efficacy of a brief, midwife-led psycho-education counselling (known as BELIEF: Birth Emotions - Looking to Improve Expectant Fear) to reduce women's childbirth fear. 1) Relative to controls, women receiving BELIEF will report lower levels of childbirth fear at term; 2) less decisional conflict; 3) less depressive symptoms; 4) better childbirth self-efficacy; and 5) improved health and obstetric outcomes. Trial registration: Australian New Zealand Controlled Trials Registry ACTRN12612000526875
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