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Best vitelliform macular dystrophy (BMD) is an autosomal dominant inherited macular degenerative disease caused by mutations in the gene BEST1 (formerly VMD2). Prior reports indicate that BMD is characterized histopathologically by accumulation of lipofuscin in the retinal pigment epithelium (RPE). However, this accumulation has not been quantified and the chemical composition of lipofuscin in BMD has not been examined. In this study we characterize the histopathology of a donor eye from a rare individual homozygous for a mutation (W93C) in BEST1. We find that this individual's disease was not any more severe than has been described for heterozygotes. We then used this tissue to quantify lipofuscin accumulation by enriching intracellular granules from RPE cells on sucrose gradients and counting the granules in each density fraction. Granules from the homozygous donor eye as well as a donor eye from an individual heterozygous for the mutation T6R were compared with age-matched control eyes. Interestingly, the least dense fraction, representing classical lipofuscin granules was either not present or significantly diminished in the BMD donor eyes and the autoflourescence associated with lipofuscin had shifted to denser fractions. However, a substantial enrichment for granules in fractions of higher density was also noted in the BMD samples. Inspection of granules from the homozygous donor eye by electron microscopy revealed a complex abnormal multilobular structure. Analysis of granules by HPLC indicated a approximately 1.6- and approximately fourfold overall increase in A2E in the BMD eyes versus age-matched control eyes, with a shift of A2E to more dense granules in the BMD donor eyes. Despite the increase in A2E and total intracellular granules, the RPE in the homozygous donor eyes was relatively well preserved. Based on these data we conclude that the clinical and histopathologic consequences to the homozygous donor were not any more severe than has been reported previously for individuals who are established or presumptive heterozygotes. We find that A2E is a component of the lipofuscin accumulated in BMD and that it is more abundant than in control eyes suggesting that the etiology of BMD is similar to Stargardt's disease and Stargardt-like macular dystrophy. Finally, the changes we observe in the granules suggest that the histopathology and eventual vision loss associated with BMD may be due to defects in the ability of the RPE to fully degrade phagocytosed photoreceptor outer segments.  相似文献   
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Thrombocytopenia remains the major dose-limiting toxicity of myelosuppressive chemotherapy in children with solid tumours. Recombinant human interleukin-11 (rhIL-11) has been approved by the Food and Drug Administration as treatment for adults with solid tumours and lymphomas with severe chemotherapy-induced thrombocytopenia. We conducted a phase I/II trial of rhIL-11 following ifosfamide, carboplatin and etoposide (ICE) chemotherapy in children with solid tumours or lymphomas. Patients received ifosfamide 1800 mg/m(2)/d for 5 d, carboplatin 400 mg/m(2)/d for 2 d and etoposide 100 mg/m(2)/d for 5 d with rhIL-11 subcutaneous (s.c.) at 25-125 microg/kg/d on days 6-33. Forty-seven patients with median age 10.5 years (range, 0.7-26 years) were studied. Median days to absolute neutrophil count >/=0.5 x 10(9)/l, platelet count >/=50 x 10(9)/l and platelet transfusions were 23, 18, 18, 16.5 and 18.5, 21, 20, 18 and 3, 3, 4, and 2 d at doses 25, 50, 75 and 100 Schulteg/kg respectively. There was a dose-dependent increase in C(max) (7.6-25.5 ng/ml), AUC(0-rho) (57-209 ng.h/ml) and T(1/2) (4-8.2 h) respectively. There was a 4% incidence of anti-IL-11 antibody formation. Clinically important adverse events to rhIL-11 were papilloedema and periosteal bone formation. In summary, rhIL-11 was well tolerated at doses of 相似文献   
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IntroductionBreast cancer is a global health problem with 2.09 million cases of breast cancer diagnosed worldwide in 2018. With an increase in breast cancer survival attention has now focussed on the impact treatment side effects can have on the quality of life for women during survivorship. The aim of the SuPPORT 4 All project is to develop a support bra for use during radiotherapy, that can reduce normal tissue toxicity (for women with larger breasts) and provide accuracy, dignity and modesty for all women. The first stage of the project involved a co-design process to understand the current patient experience where no support bra or modesty device is used.MethodA participatory co-design methodology was adopted. Workshops were held with patient representatives (n = 9) to seek understanding of experience during radiotherapy; a total of three workshops over 4 h. The workshops were audio recorded and framework analysis was adopted to identify key patient experiences.ResultsTwelve categories and twenty-six sub categories were identified specific to patient experience. Patient concerns focussed on information provision, Healthcare Practitioner (HCP) knowledge of breast lymphoedema, lack of choice, experiences of being naked, and feelings of disempowerment.ConclusionsA number of areas were identified that had negative effects on overall patient experience.Implications for practicePractitioners should consider patient dignity when configuring services to support patient needs regarding undressing, outside or inside the linear accelerator room. Additionally, practitioners should have an understanding of the impact permanent tattoos may have on some patients’ wellbeing and the impact that breast lymphoedema has on patient quality of life. Practitioners should also consider methods to encourage patient empowerment during radiotherapy; supporting patient self-monitoring of side-effects may be one way to facilitate this.  相似文献   
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