Identification of novel mutations in Chinese Hans with autosomal dominant polycystic kidney disease

<p>Abstract</p> <p>Background</p> <p>Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited renal disease with an incidence of 1 in 400 to 1000. The disease is genetically heterogeneous, with two genes identified: <it>PKD1 </it>(16p13.3) and <it>PKD2 </it>(4q21). Molecular diagnosis of the disease in at-risk individuals is complicated due to the structural complexity of <it>PKD1 </it>gene and the high diversity of the mutations. This study is the first systematic ADPKD mutation analysis of both <it>PKD1 </it>and <it>PKD2 </it>genes in Chinese patients using denaturing high-performance liquid chromatography (DHPLC).</p> <p>Methods</p> <p>Both <it>PKD1 </it>and <it>PKD2 </it>genes were mutation screened in each proband from 65 families using DHPLC followed by DNA sequencing. Novel variations found in the probands were checked in their family members available and 100 unrelated normal controls. Then the pathogenic potential of the variations of unknown significance was examined by evolutionary comparison, effects of amino acid substitutions on protein structure, and effects of splice site alterations using online mutation prediction resources.</p> <p>Results</p> <p>A total of 92 variations were identified, including 27 reported previously. Definitely pathogenic mutations (ten frameshift, ten nonsense, two splicing defects and one duplication) were identified in 28 families, and probably pathogenic mutations were found in an additional six families, giving a total detection level of 52.3% (34/65). About 69% (20/29) of the mutations are first reported with a recurrent mutation rate of 31%.</p> <p>Conclusions</p> <p>Mutation study of <it>PKD1 </it>and <it>PKD2 </it>genes in Chinese Hans with ADPKD may contribute to a better understanding of the genetic diversity between different ethnic groups and enrich the mutation database. Besides, evaluating the pathogenic potential of novel variations should also facilitate the clinical diagnosis and genetic counseling of the disease.</p

Imaging Novel Ruthenium bipyridine-based Nanophotoswitches in Retina

Nanophotoswitches (NPSs) offer a new tool for optical stimulation of neuronal activity, in vitro and also potentially in vivo. Our group previously reported a ruthenium bipyridine (Rubpy)-based NPS that inserts into the plasma membrane and upon visible illumination generates an electrical dipole, triggering action potentials in adrenal chromaffin cells. We have recently demonstrated that after intravitreal injection of this NPS into the eyes of blind rats, illumination of the eye elicited electrical activity in the contralateral superior colliculus. To better understand the site of action of the NPS in retina, we examined the distribution of the molecules in different retinal layers after intravitreal injection. Methods: Rubpy molecules can be visualized by their luminescence (610 nm) upon visible wavelength illumination (460 nm). To resolve the luminescence from different retinal layers, a rapid-scan twophoton imaging system (LaVison) was used (Ti:Sapphire laser tuned to 900 nm). Intravitreal injection (1 mM, 4 μL Rubpy-based NPSs in BSS), followed by eye removal and retina isolation 2-5 hrs after, was performed on young RCS rats. Luminescence images of the wholemount retina were captured by an EM-CCD camera (Andor). Results: At 2 hrs after intravitreal injection and with continuous superfusion of Ames medium, luminescence was confined near the injection site. Luminescence was observed localized to surface membranes of axons and somata of retinal ganglion cells (RGC), demonstrating the impermeability of the cell membrane to the NPS molecules. The outer retina did not show significant luminescence. After 3 additional hours, luminescence was more diffused within the RGC layer and still did not extend to the outer retina. Conclusions: This study shows marked staining of RGC layer by intravitreally injected Rubpy-based NPS molecules, consistent with the hypothesis that the photoactivated NPS molecules induce electrical activity in the superior colliculus by acting on the RGCs that deliver electrical signals to the visual pathway outside the eyes. Distinct from other nano-scale optical cellular modulating approaches using optogenetics or azobenzene-based photoswitches, the NPS approach obviates the need for gene manipulation or toxic UV illumination, highlighting its potential in generating high-acuity prosthetic vision in patients blinded by retinal degenerative diseases

Nanomicelle formulation modifies the pharmacokinetic profiles and cardiac toxicity of daunorubicin.

BackgroundTreatment with daunorubicin (DNR) in acute myeloid leukemia is moderately effective and associated with significant side effects, including cardiac toxicity. We recently developed a nanomicellar formulation of DNR that specifically targets acute myeloid leukemia stem cells.Materials &amp; methodsPharmacokinetics analysis of free DNR, DNR in nanomicellar formulations was performed in Balb/c mice and Sprague-Dawley rats. Histochemical staining, caspase 3/7, troponin and creatine kinase MB isoenzyme were used to assess toxicity.ResultsCompared with free DNR, the nanomicellar formulations of DNR had less cardiotoxicity as evidenced by milder histopathological changes, lower caspase 3/7 activity in heart tissue (p = 0.002), lower plasma creatine kinase MB isoenzyme (p = 0.002) and troponin concentrations (p = 0.001) postinjection. The area under curve concentration of DNR in micelles increased by 31.9-fold in mice (p &lt; 0.0001) and 22.0-fold higher in rats (p &lt; 0.001).ConclusionLeukemia stem cell-targeting micelles dramatically change the pharmacokinetics and reduce the cardiac toxicity of DNR, which may enable improved DNR-based treatment of acute myeloid leukemia

Nanomicelle formulation modifies the pharmacokinetic profiles and cardiac toxicity of daunorubicin.

BackgroundTreatment with daunorubicin (DNR) in acute myeloid leukemia is moderately effective and associated with significant side effects, including cardiac toxicity. We recently developed a nanomicellar formulation of DNR that specifically targets acute myeloid leukemia stem cells.Materials &amp; methodsPharmacokinetics analysis of free DNR, DNR in nanomicellar formulations was performed in Balb/c mice and Sprague-Dawley rats. Histochemical staining, caspase 3/7, troponin and creatine kinase MB isoenzyme were used to assess toxicity.ResultsCompared with free DNR, the nanomicellar formulations of DNR had less cardiotoxicity as evidenced by milder histopathological changes, lower caspase 3/7 activity in heart tissue (p = 0.002), lower plasma creatine kinase MB isoenzyme (p = 0.002) and troponin concentrations (p = 0.001) postinjection. The area under curve concentration of DNR in micelles increased by 31.9-fold in mice (p &lt; 0.0001) and 22.0-fold higher in rats (p &lt; 0.001).ConclusionLeukemia stem cell-targeting micelles dramatically change the pharmacokinetics and reduce the cardiac toxicity of DNR, which may enable improved DNR-based treatment of acute myeloid leukemia

Nanomicelle formulation modifies the pharmacokinetic profiles and cardiac toxicity of daunorubicin

BACKGROUND: Treatment with daunorubicin (DNR) in acute myeloid leukemia is moderately effective and associated with significant side effects, including cardiac toxicity. We recently developed a nanomicellar formulation of DNR that specifically targets acute myeloid leukemia stem cells. MATERIALS & METHODS: Pharmacokinetics analysis of free DNR, DNR in nanomicellar formulations was performed in Balb/c mice and Sprague–Dawley rats. Histochemical staining, caspase 3/7, troponin and creatine kinase MB isoenzyme were used to assess toxicity. RESULTS: Compared with free DNR, the nanomicellar formulations of DNR had less cardiotoxicity as evidenced by milder histopathological changes, lower caspase 3/7 activity in heart tissue (p = 0.002), lower plasma creatine kinase MB isoenzyme (p = 0.002) and troponin concentrations (p = 0.001) postinjection. The area under curve concentration of DNR in micelles increased by 31.9-fold in mice (p < 0.0001) and 22.0-fold higher in rats (p < 0.001). CONCLUSION: Leukemia stem cell-targeting micelles dramatically change the pharmacokinetics and reduce the cardiac toxicity of DNR, which may enable improved DNR-based treatment of acute myeloid leukemia