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41.

Purpose

To evaluate the safety and efficacy of selective internal radiation therapy (SIRT) in patients with unresectable liver metastases from neuroendocrine tumours (NETLMs).

Methods

This retrospective study included 40 patients with progressive NETLMs (22 women, 18 men, mean age 61.6 years) who underwent SIRT with 90Y-labelled resin microspheres. Tumour response was evaluated according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) on CT or MR images. Medical records were reviewed.

Results

In the 40 patients, 54 evaluable SIRT procedures were performed, 33 to the right liver lobe (mean activity 1.31 GBq), 13 to the left lobe (mean activity 0.85 GBq), and 8 to both lobes (mean activity 1.61 GBq). Late follow-up imaging (mean 20 months) was performed after 44 of the treatments. Objective tumour response and disease control rates were 54 % (29 of 54 treatments) and 94 % (51 treatments), respectively, at the early follow-up examination (mean 3 months) and 34 % (15 treatments) and 57 % (25 treatments), respectively at the late follow-up examination. Mean overall survival from the first SIRT was 34,8 months and survival rates at 1, 2, 3 and 5 years were 76 %, 59 %, 52 % and 35 % respectively. Adverse effects were generally mild and easily manageable, except in one patient who died from radiation-induced liver failure. Of the 45 patients, 18 (45 %) had received peptide receptor radionuclide therapy (PRRT) prior to SIRT.

Conclusion

SIRT with 90Y-labelled resin microspheres is a safe and effective treatment for patients with progressive NETLM, and also for those who have received prior PRRT.
  相似文献   
42.

Background and Aim

Swedish health registries are common sources of data for studies on the effects of obesity surgery, and there is a need to assess the quality of data in these registries. The aim of this study was to validate the registration of obesity surgery in the National Patient Registry (NPR) and the Scandinavian Obesity Surgery Registry (SOReg).

Method

We randomly selected 962 out of 8501 registrations of obesity surgery in 2011 from the NPR and SOReg. Registered surgical procedures in the NPR and SOReg were compared to the medical records, and concordance was analyzed by calculating positive predictive value (PPV) with 95 % confidence interval (CI).

Results

We received 938 (98 %) medical records for manual review. The overall PPV for obesity surgery was high in the NPR (PPV 97.0; 95 % CI 95.6–98.4) and even higher in SOReg (PPV 99.7; 95 % CI 99.3–100). Accuracy was higher for gastric bypass surgery than for other types of obesity surgery. Registrations that were misclassified as obesity surgery (n?=?44) included reoperations due to complications or reconstruction to normal anatomy after previous obesity surgery (n?=?11) and endoscopic procedures (n?=?10).

Conclusion

Obesity surgery registrations in the NPR and SOReg have high accuracy and are reliable sources of data to identify patients having undergone obesity surgery. When it is of importance to distinguish between specific surgical procedures, non-gastric bypass surgeries in the NPR should ideally be supplemented with data from other sources.
  相似文献   
43.
MR (mineralocorticoid receptor) activation by either administration of exogenous mineralocorticoids or by allowing endogenous glucocorticoids to activate the MR has been shown to produce oxidative stress and vascular inflammation at the earliest stages of the development of cardiac fibrosis in experimental animals. These studies suggest potential mechanisms for the benefits observed in recent large scale clinical trials investigating the cardioprotective effects of MR antagonists given in conjunction with current best practice therapy for moderate-to-severe heart failure and heart failure post-myocardial infarction. Given that few patients had elevated plasma aldosterone, novel mechanisms involved in activating the MR in the failing heart are now being investigated.  相似文献   
44.
Cytokinin signaling regulates cambial development in poplar   总被引:2,自引:0,他引:2       下载免费PDF全文
Although a substantial proportion of plant biomass originates from the activity of vascular cambium, the molecular basis of radial plant growth is still largely unknown. To address whether cytokinins are required for cambial activity, we studied cytokinin signaling across the cambial zones of 2 tree species, poplar (Populus trichocarpa) and birch (Betula pendula). We observed an expression peak for genes encoding cytokinin receptors in the dividing cambial cells. We reduced cytokinin levels endogenously by engineering transgenic poplar trees (P. tremula × tremuloides) to express a cytokinin catabolic gene, Arabidopsis CYTOKININ OXIDASE 2, under the promoter of a birch CYTOKININ RECEPTOR 1 gene. Transgenic trees showed reduced concentration of a biologically active cytokinin, correlating with impaired cytokinin responsiveness. In these trees, both apical and radial growth was compromised. However, radial growth was more affected, as illustrated by a thinner stem diameter than in WT at same height. To dissect radial from apical growth inhibition, we performed a reciprocal grafting experiment. WT scion outgrew the diameter of transgenic stock, implicating cytokinin activity as a direct determinant of radial growth. The reduced radial growth correlated with a reduced number of cambial cell layers. Moreover, expression of a cytokinin primary response gene was dramatically reduced in the thin-stemmed transgenic trees. Thus, a reduced level of cytokinin signaling is the primary basis for the impaired cambial growth observed. Together, our results show that cytokinins are major hormonal regulators required for cambial development.  相似文献   
45.
Adipogenesis is spatiotemporally coupled to angiogenesis throughout adult life, and the interplay between these two processes is communicated by multiple factors. Here we show that in a transgenic mouse model, increased expression of forkhead box C2 (FOXC2) in the adipose tissue affects angiogenesis, vascular patterning, and functions. White and brown adipose tissues contain a considerably high density of microvessels appearing as vascular plexuses, which show redistribution of vascular smooth muscle cells and pericytes. Dysfunction of these primitive vessels is reflected by impairment of skin wound healing. We further provide a mechanistic insight of the vascular phenotype by showing that FOXC2 controls Ang-2 expression by direct activation of its promoter in adipocytes. Remarkably, an Ang-2-specific antagonist almost completely reverses this vascular phenotype. Thus, the FOXC2-Ang-2 signaling system is crucial for controlling adipose vascular function, which is part of an adaptation to increased adipose tissue metabolism.  相似文献   
46.
Immune reactions to cysticercosis have been extensively studied in mice. The lack of significant lymphocyte infiltration into the livers of infected mice and the obvious role of antibodies in rejection has led to the general conclusion that cellular reactions do not play a role in protection against this disease. In contrast, the present study examining the immune response to cestode infections in a large animal model (sheep) revealed the presence of a massive and highly organized cellular infiltration in the livers after a secondary Taenia hydatigena infection. The majority of the infiltrating lymphocytes were of the CD4+ phenotype with much fewer CD8+ cells present. While most gamma delta-TCR+ cells in peripheral blood are SBU-T19+, the majority of gamma delta-TCR+ lymphocytes in the liver lesions are SBU-T19- suggesting selective migration of these cells into the lesions. In contrast to the diffuse distribution of T cells in the lesions, B cells were present as distinct aggregates. In primary T. hydatigena infections, host class I and class II MHC antigens were shown, for the first time in cestode infections, to be absorbed onto the surface of the metacestode bladderwall indicating their possible involvement in parasite survival. No immune reactions were observed close to the parasite although lymphocytes and eosinophils were infiltrating the adjacent portal tract areas. Most lymphocytes in both primary and secondary infections were positive for MHC class II antigens suggesting selective recruitment of activated cells to the site of infection. Significant changes in relative and absolute numbers of lymphocyte subpopulations were also observed in the draining hepatic lymph nodes dominated by a massive increase of B cells. In contrast, at the peak of local cellular infiltration, no changes in lymphocyte subpopulations were observed in peripheral blood showing the limited usefulness of this compartment in studying cellular changes in localized infections. The vigorous cellular response observed in the livers of sheep contrasts sharply with the lack of lymphocyte infiltration reported in mice indicating that small animal models may not be appropriate to study cellular responses to cysticercosis in large animals and man.  相似文献   
47.
Intranasal corticosteroids have been shown to decrease ocular symptoms associated with allergic rhinitis as well as nasal symptoms. The primary objective of this retrospective analysis was to evaluate the efficacy of fluticasone propionate (FP) aqueous nasal spray in the treatment of ocular symptoms in patients with seasonal allergic rhinitis (SAR). We pooled efficacy data from seven multicenter, randomized, double-blind, placebo-controlled studies of similar design. Each study evaluated the efficacy of intranasal FP, 200 micrograms, given once daily in the treatment of nasal and ocular symptoms associated with SAR. At baseline and after 7 and 14 days of treatment, clinicians rated the severity of four individual ocular symptoms (itching, tearing, redness, and puffiness) via visual analog scales of 0-100, where 0 = no symptoms and 100 = worst symptoms. The four ratings were added to form the total ocular symptom score (TOSS). Patients rated the overall severity of their ocular symptoms (all symptoms evaluated with a single score) daily on diary cards in a similar fashion. The primary outcome was the mean change from baseline in the clinician-rated TOSS. A between-group difference of 25 points in the mean change from baseline TOSS by day 14 was considered clinically relevant. The FP group had greater mean changes from baseline in the TOSS and in all four individual symptom scores compared with placebo at days 7 and 14. At day 7, mean decreases from baseline in the TOSS were 76.0 points for the FP group and 50.9 points for the placebo group (p < 0.001), a difference between groups of 25.1. At day 14, mean decreases from baseline in the TOSS were 91.8 points for the FP group and 60.2 points for the placebo group (p < 0.001), a difference between groups of 31.6. Consistent with the clinician-rated data, patient-rated data showed a significantly greater reduction in the overall ocular symptom score for the FP group compared with placebo for both weeks 1 and 2 (p < 0.001). Intranasal FP provides safe and effective relief of ocular symptoms associated with SAR. Patients with allergic rhinitis who also have ocular symptoms as a component of their disease may benefit from intranasal FP monotherapy without the addition of topical ophthalmologic agents or oral antihistamines. Such an approach may have advantages regarding compliance and cost-effectiveness of treatment.  相似文献   
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