28 research outputs found

    Pornography Use Profiles and the Emergence of Sexual Behaviors in Adolescence

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    This research longitudinally explored adolescent pornography (porn) consumption and its association with sexual development in early and middle adolescence. A four-wave design with half-year intervals investigated pornography consumption and different (sexual) activities, such as masturbation, French kissing, petting, giving/receiving manual and oral sex, and intercourse, among 630 respondents (47.9% female, mean age 13.7 years; SD = 0.48) years at T1). A latent growth mixture analysis of pornography consumption revealed two groups with relatively low pornography (LP; 51.8% of the boys, 91.4% of the girls) versus high pornography (HP; 48.2% of the boys; 8.6% of the girls) consumption across time. At T1, HP boys on average watched pornography less than once a month, but more than once a year at T1. At T4, their average pornography use had increased to almost one to two times a week. LP boys never watched pornography at T1. At T4, their average pornography use was still less than once a year. At T1, HP girls never watched pornography, but consumption increased to almost one to three times a month at T4. Across waves of the study, LP girls (almost) never watched pornography. A discrete-time survival mixture analysis of sexual developmental patterning indicated that, compared to their LP peers, both girls and boys in the HP groups showed accelerated development of masturbation, petting, and receiving manual sex. Girls in the HP group were also more inclined to receive oral sex, whereas boys in the HP group also showed earlier and more frequent manual sex and intercourse. Thus, whereas the HP group of boys was substantially larger compared to that of girls, pornography consumption was related to accelerated development of sexual activities for both genders across early and middle adolescence. The discussion deliberates on pornography as a driving force in adolescent sexual development versus pornography as a medium of choice for sexually advanced adolescents

    Sequencing of neuroblastoma identifies chromothripsis and defects in neuritogenesis genes

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    Neuroblastoma is a childhood tumour of the peripheral sympathetic nervous system. The pathogenesis has for a long time been quite enigmatic, as only very few gene defects were identified in this often lethal tumour. Frequently detected gene alterations are limited to MYCN amplification (20%) and ALK activations (7%). Here we present a whole-genome sequence analysis of 87 neuroblastoma of all stages. Few recurrent amino-acid-changing mutations were found. In contrast, analysis of structural defects identified a local shredding of chromosomes, known as chromothripsis, in 18% of high-stage neuroblastoma. These tumours are associated with a poor outcome. Structural alterations recurrently affected ODZ3, PTPRD and CSMD1, which are involved in neuronal growth cone stabilization. In addition, ATRX, TIAM1 and a series of regulators of the Rac/Rho pathway were mutated, further implicating defects in neuritogenesis in neuroblastoma. Most tumours with defects in these genes were aggressive high-stage neuroblastomas, but did not carry MYCN amplifications. The genomic landscape of neuroblastoma therefore reveals two novel molecular defects, chromothripsis and neuritogenesis gene alterations, which frequently occur in high-risk tumours

    Nutrient removal by NF and RO membranes in a decentralized sanitation system

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    Decentralized treatment of domestic wastewater offers the possibility of water and nutrient reuse. In a decentralized sanitation system the household wastewater streams are separated in a large diluted stream (gray water) and a small and concentrated stream (black water) containing important nutrients like ammonium and phosphate. Nanofiltration (NF) and reverse osmosis (RO) membranes might be used to recover the nutrients from anaerobically treated black water. The permeate might be used in a water reuse scheme. In case of water reuse the produced permeate should meet guidelines for potable water or meet new guidelines which might be applied in the future for intermediate quality of water, for example toilet flushwater; when this is not possible the permeate should meet guidelines for discharge. The most stringent guidelines apply for ammonium and phosphate. The focus of this paper is to test commercially available NF and RO membranes to remove nutrients from anaerobically treated black water in order to meet the Dutch guidelines. A large number of commercial tubular, capillary and flat sheet NF and RO membranes was tested on laboratory scale on their performance to meet the Dutch guidelines for ammonium and phosphate. The ammonium and phosphate concentrations used were based on the effluent composition of anaerobically treated black water. Ammonium and phosphate rejection were both measured in synthetic single salt and multi-ion mixtures and in anaerobic effluent.\ud \ud The rejection for ammonium (30¿95%) is neither sufficient for discharge nor potable water use. The rejection of phosphate (74¿99%) is in most cases almost sufficient to meet the standards for potable water

    Pornography use profiles and the emergence of sexual behaviors in adolescence

    Get PDF
    This research longitudinally explored adolescent pornography (porn) consumption and its association with sexual development in early and middle adolescence. A four-wave design with half-year intervals investigated pornography consumption and different (sexual) activities, such as masturbation, French kissing, petting, giving/receiving manual and oral sex, and intercourse, among 630 respondents (47.9% female, mean age 13.7 years; SD = 0.48) years at T1). A latent growth mixture analysis of pornography consumption revealed two groups with relatively low pornography (LP; 51.8% of the boys, 91.4% of the girls) versus high pornography (HP; 48.2% of the boys; 8.6% of the girls) consumption across time. At T1, HP boys on average watched pornography less than once a month, but more than once a year at T1. At T4, their average pornography use had increased to almost one to two times a week. LP boys never watched pornography at T1. At T4, their average pornography use was still less than once a year. At T1, HP girls never watched pornography, but consumption increased to almost one to three times a month at T4. Across waves of the study, LP girls (almost) never watched pornography. A discrete-time survival mixture analysis of sexual developmental patterning indicated that, compared to their LP peers, both girls and boys in the HP groups showed accelerated development of masturbation, petting, and receiving manual sex. Girls in the HP group were also more inclined to receive oral sex, whereas boys in the HP group also showed earlier and more frequent manual sex and intercourse. Thus, whereas the HP group of boys was substantially larger compared to that of girls, pornography consumption was related to accelerated development of sexual activities for both genders across early and middle adolescence. The discussion deliberates on pornography as a driving force in adolescent sexual development versus pornography as a medium of choice for sexually advanced adolescents

    Image Guided Brachytherapy for Cancer of the Nasal Vestibule: Local Control and Cosmesis

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    Purpose: To evaluate the efficacy of modern image guided brachytherapy for squamous cell carcinoma of the nasal vestibule, to explore tumor volume as a prognostic factor for local and regional recurrence, and to assess patient satisfaction with nasal function and appearance after treatment. Methods and Materials: In a retrospective analysis, we reviewed the medical records of 102 patients with Wang T1-T2 nasal vestibule cancer treated at a single institution with brachytherapy as the sole treatment. Median follow-up time was 42 months (range, 3-210 months). A patient satisfaction study using the validated Nasal Appearance and Function Evaluation Questionnaire was conducted among 42 patients more than 1 year after treatment. A statistically significant cutoff point for tumor volume as a prognostic factor of local control was established using Youden's index method. Results: Seventy-seven of 102 patients were treated with interstitial implants, and 25 patients were treated by an intracavitary mould technique. The 5-year control rates were 95%, 91%, and 83% for local, regional, and locoregional control, respectively. Tumor volume ≥2.3 cm 3 resulted in worse 3-year regional control compared to tumor volume <2.3 cm 3 (62% vs 96%; P =.01). Ultimate regional control after salvage treatment was 96%, with no significant difference observed between subgroups by tumor volume (92% for ≥2.3 cm 3 vs 96% for <2.3 cm 3 ; P =.57). Three patients with regional failure developed distant metastases. Five-year disease-specific survival and overall survival were 94% and 74%, respectively. Patient-assessed cosmetic and functional satisfaction were both rated high (mean 3.7 and 4.0 of 5, respectively). Conclusion: We report the largest cohort to date treated with brachytherapy as the sole treatment for nasal vestibule carcinoma. Brachytherapy offers excellent local control for Wang T1-T2 tumors with high patient satisfaction. Tumor volume is an adequate predictive factor for patients at risk of regional recurrence, but ultimate control rates after salvage treatment are high. Therefore, we do not recommend elective treatment of the neck

    Specific and Sensitive Detection of Neuroblastoma mRNA Markers by Multiplex RT-qPCR

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    mRNA RT-qPCR is shown to be a very sensitive technique to detect minimal residual disease (MRD) in patients with neuroblastoma. Multiple mRNA markers are known to detect heterogeneous neuroblastoma cells in bone marrow (BM) or blood from patients. However, the limited volumes of BM and blood available can hamper the detection of multiple markers. To make optimal use of these samples, we developed a multiplex RT-qPCR for the detection of MRD in neuroblastoma. GUSB and PHOX2B were tested as single markers. The adrenergic markers TH, GAP43, CHRNA3 and DBH and mesenchymal markers POSTN, PRRX1 and FMO3 were tested in multiplex. Using control blood and BM, we established new thresholds for positivity. Comparison of multiplex and singleplex RT-qPCR results from 21 blood and 24 BM samples from neuroblastoma patients demonstrated a comparable sensitivity. With this multiplex RT-qPCR, we are able to test seven different neuroblastoma mRNA markers, which overcomes tumor heterogeneity and improves sensitivity of MRD detection, even in those samples of low RNA quantity. With resources and time being saved, reduction in sample volume and consumables can assist in the introduction of MRD by RT-qPCR into clinical practice

    Merkel Cell Carcinoma: New Trends

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    Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor of the skin mainly seen in the elderly. Its incidence is rising due to ageing of the population, increased sun exposure, and the use of immunosuppressive medication. Additionally, with the availability of specific immunohistochemical markers, MCC is easier to recognize. Typically, these tumors are rapidly progressive and behave aggressively, emphasizing the need for early detection and prompt diagnostic work-up and start of treatment. In this review, the tumor biology and immunology, current diagnostic and treatment modalities, as well as new and combined therapies for MCC, are discussed. MCC is a very immunogenic tumor which offers good prospects for immunotherapy. Given its rarity, the aggressiveness, and the frail patient population it concerns, MCC should be managed in close collaboration with an experienced multidisciplinary team

    F-18-FDG-PET/CT-based treatment planning for definitive (chemo) radiotherapy in patients with head and neck squamous cell carcinoma improves regional control and survival

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    Background and purpose: Multimodality imaging including 18F-FDG-PET has improved the detection threshold of nodal metastases in head and neck squamous cell carcinoma (HNSCC). The aim of this retrospective analysis is to investigate the impact of FDG-PET/CT-based nodal target volume definition (FDG-PET/CT-based NTV) on radiotherapy outcomes, compared to conventional CT-based nodal target volume definition (CT-based NTV). Materials and methods: Six-hundred-thirty-three patients treated for HNSCC with definitive (chemo)radiotherapy using IMRT/VMAT techniques between 2008 and 2017 were analyzed. FDG-PET/CT-based NTV was performed in 46% of the patients. The median follow-up was 31 months. Diagnostic imaging depicting the regional recurrence was co-registered with the initial CT-scan to reconstruct the exact site of the recurrence. Multivariate Cox regression analysis was performed to identify variables associated with radiotherapy outcome. Results: FDG-PET/CT-based NTV improved control of disease in the CTV elective-nodal (HR: 0.33, p = 0.026), overall regional control (HR: 0.62, p = 0.027) and overall survival (HR: 0.71, p = 0.033) compared to CT-based NTV. The risk for recurrence in the CTV elective-nodal was increased in case of synchronous local recurrence of the primary tumor (HR: 12.4, p < 0.001). Conclusion: FDG-PET/CT-based NTV significantly improved control of disease in the CTV elective-nodal, overall regional control and overall survival compared to CT-based NTV. A significant proportion of CTV elective-nodal recurrences are potentially new nodal manifestations from a synchronous local recurrent primary tumor. These results support the concept of target volume transformation and give an indication of the potential of FDG-PET to guide gradual radiotherapy dose de-escalation in elective neck treatment in HNSCC

    18F-FDG-PET/CT-based treatment planning for definitive (chemo)radiotherapy in patients with head and neck squamous cell carcinoma improves regional control and survival

    No full text
    Background and purpose: Multimodality imaging including 18F-FDG-PET has improved the detection threshold of nodal metastases in head and neck squamous cell carcinoma (HNSCC). The aim of this retrospective analysis is to investigate the impact of FDG-PET/CT-based nodal target volume definition (FDG-PET/CT-based NTV) on radiotherapy outcomes, compared to conventional CT-based nodal target volume definition (CT-based NTV). Materials and methods: Six-hundred-thirty-three patients treated for HNSCC with definitive (chemo)radiotherapy using IMRT/VMAT techniques between 2008 and 2017 were analyzed. FDG-PET/CT-based NTV was performed in 46% of the patients. The median follow-up was 31 months. Diagnostic imaging depicting the regional recurrence was co-registered with the initial CT-scan to reconstruct the exact site of the recurrence. Multivariate Cox regression analysis was performed to identify variables associated with radiotherapy outcome. Results: FDG-PET/CT-based NTV improved control of disease in the CTV elective-nodal (HR: 0.33, p = 0.026), overall regional control (HR: 0.62, p = 0.027) and overall survival (HR: 0.71, p = 0.033) compared to CT-based NTV. The risk for recurrence in the CTV elective-nodal was increased in case of synchronous local recurrence of the primary tumor (HR: 12.4, p < 0.001). Conclusion: FDG-PET/CT-based NTV significantly improved control of disease in the CTV elective-nodal, overall regional control and overall survival compared to CT-based NTV. A significant proportion of CTV elective-nodal recurrences are potentially new nodal manifestations from a synchronous local recurrent primary tumor. These results support the concept of target volume transformation and give an indication of the potential of FDG-PET to guide gradual radiotherapy dose de-escalation in elective neck treatment in HNSCC
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