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71.
In β-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by β-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle–promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-XL. The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder.  相似文献   
72.
Double-dose hepatitis B virus revaccination of human immunodeficiency virus (HIV)-infected patients proved to be effective in 50.7% of 144 patients who had previously failed to respond to standard doses. In the multivariate analysis, female patients were found to have a significantly better response (P= .03). The effect of age on the response depended on the viral load at the time of revaccination. For patients with a detectable HIV RNA load, the effect of age was stronger (odds ratio [OR], 0.34 per 10 years older [95% confidence interval {CI}, 0.16-0.72]; P= .005) than for patients with an undetectable HIV RNA load (OR, 0.74 per 10 years older [95% CI, 0.50-1.09]; P= .12).  相似文献   
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75.

Purpose

With the introduction of biosimilars of anticancer monoclonal antibodies (mAbs) in oncology, physicians are potentially confronted with the question whether it is clinically adequate to switch patients who are clinically stable on treatment with the reference product to a newly available biosimilar (or vice versa/from 1 biosimilar to another). For a proper impact assessment of switching, robust, product-specific, and clinically relevant evidence should be required, ideally including data from appropriately designed switching studies. In this article, we assess the current body of switching data available for approved or proposed biosimilars of anticancer mAbs.

Methods

PubMed was systematically searched and ClinicalTrials.gov and abstract databases of selected congresses were hand-searched to identify all switching studies including biosimilars of anticancer mAbs.

Findings

We identified 8 switching studies with biosimilars of rituximab (CT-P10, GP2013, PF-05280586, and BCD-020) and trastuzumab (ABP 980). Two were performed in oncology indications and the other 6 in rheumatoid arthritis (RA). Key elements of a well-designed switching study, such as randomization and blinding, were contained in several of the studies, but significant limitations were also present. The most frequent limitations were low statistical power because of small patient numbers, lack of an appropriate control arm, short follow-up, chosen outcome measures, and (for studies performed in RA) the concern whether switching data can be extrapolated to oncology indications. Accordingly, the data from these studies need to be interpreted with caution. Of note, all identified studies included a single switch only, whereas multiple switches may occur in the real-world setting. The scientific need to evaluate the impact of repeated switching has been recognized by the US Food and Drug Administration, who incorporated such a requirement in its draft guidance on interchangeability.

Implications

From the scarce data available, the consequences of switching between reference product mAbs and their biosimilar(s) in the oncology setting are as yet unknown. Additional clinical evidence from well-designed switching studies is needed to guide switching decisions.  相似文献   
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Purpose

Choroidal neovascularization (CNV) associated with punctate inner choroidopathy (PIC) is a rare clinical entity, yet still a challenge for medical treatment. A case of a young myopic woman developing CNV secondary to unilateral PIC is presented. Clinical morphology, diagnostic procedure and follow-up are reported.

Case Report

A 29-year-old woman presented with multiple yellowish dots at the posterior pole. No other signs of inflammation could be seen. Angiography with fluorescein yielded hyperfluorescent signals in the affected areas with a diffuse leak, and SD-OCT showed a slightly elevated retinal pigment epithelial layer, consistent with the diagnosis of PIC. Additionally a classic CNV was observed.

Results

Anti-inflammatory therapy with local prednisolone acetate eye drops in combination with intravitreal injection of anti-vascular endothelial growth factor (VEGF, bevacizumab) yielded an increased best-corrected visual acuity. As CNV reappeared, systemic medication with prednisone and azathioprine in combination with two further intravitreal injections of anti-VEGF stabilized CNV and increased visual acuity again.

Conclusion

Combined therapy of immunosuppression with intravitreal anti-VEGF injections can be considered as therapeutic strategy in the management of recurrent CNV associated with PIC.Key Words: Punctate inner choroidopathy, Choroidal neovascularization, Intravitreal anti-VEGF therapy, Choroiditis  相似文献   
78.
Journal of Thrombosis and Thrombolysis - The role of the A>G polymorphism at position 19911 in the prothrombin gene (factor [F] 2 at rs3136516) as a risk factor for venous thromboembolism...  相似文献   
79.
Pituitary - Non-osmotic stimulation tests using glucagon, arginine, or macimorelin were recently evaluated for their ability to assess posterior pituitary function. Glucagon and arginine, but not...  相似文献   
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