Parkin-mediated protection of dopaminergic neurons in a chronic MPTP-minipump mouse model of Parkinson disease

Loss-of-function mutations in the ubiquitin ligase parkin are the major cause of recessively inherited early-onset Parkinson disease (PD). Impairment of parkin activity caused by nitrosative or dopamine-related modifications may also be responsible for the loss of dopaminergic (DA) neurons in sporadic PD. Previous studies have shown that viral vector-mediated delivery of parkin prevented DA neurodegeneration in several animal models, but little is known about the neuroprotective actions of parkin in vivo. Here, we investigated mechanisms of neuroprotection of overexpressed parkin in a modified long-term mouse model of PD using osmotic minipump administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Recombinant adeno-associated viral vector-mediated intranigral delivery of parkin prevented motor deficits and DA cell loss in the mice. Ser129-phosphorylated α-synuclein-immunoreactive cells were increased in the substantia nigra of parkin-treated mice. Moreover, delivery of parkin alleviated the MPTP-induced decrease of the active phosphorylated form of Akt. On the other hand, upregulation of p53 and mitochondrial alterations induced by chronic MPTP administration were barely suppressed by parkin. These results suggest that the neuroprotective actions of parkin may be impaired in severe PD.     

A preliminary feasibility study of simultaneous dual-isotope imaging with a solid-state dedicated cardiac camera for evaluating myocardial perfusion and fatty acid metabolism

Simultaneous dual-isotope SPECT imaging with 201Tl and ¹²³I-β-methyl-p-iodophenylpentadecanoic acid (BMIPP) is used to study the perfusion–metabolism mismatch. It predicts post-ischemic functional recovery by detecting stunned myocardium. On the other hand, ^99mTc-MIBI is another radioisotope widely used in myocardial perfusion imaging because of its better image quality and lower radiation exposure than 201Tl. However, since the photopeak energies of ^99mTc and ¹²³I are very similar, crosstalk hampers the simultaneous use of these two radioisotopes. To overcome this problem, we conducted simultaneous dual-isotope imaging study using the D-SPECT scanner (Spectrum-Dynamics, Israel) which has a novel detector design and excellent energy resolution. We first conducted a basic experiment using cardiac phantom to simulate the condition of normal perfusion and impaired fatty acid metabolism. Subsequently, we prospectively recruited 30 consecutive patients who underwent successful percutaneous coronary intervention for acute myocardial infarction, and performed ^99mTc-MIBI/¹²³I-BMIPP dual-isotope imaging within 5 days after reperfusion. Images were interpreted by two experienced cardiovascular radiologists to identify the infarcted and stunned areas based on the coronary artery territories. As a result, cardiac phantom experiment revealed no significant crosstalk between ^99mTc and ¹²³I. In the subsequent clinical study, ^99mTc-MIBI/¹²³I-BMIPP dual-isotope imaging in all participant yielded excellent image quality and detected infarcted and stunned areas correctly when compared with coronary angiographic findings. Furthermore, we were able to reduce radiation exposure to significantly approximately one-eighth. In conclusion, we successfully demonstrated the practical application of simultaneous assessment of myocardial perfusion and fatty acid metabolism by ^99mTc-MIBI and ¹²³I-BMIPP using a D-SPECT cardiac scanner. Compared with conventional ²⁰¹TlCl/¹²³I-BMIPP dual-isotope imaging, the use of ^99mTc-MIBI instead of ²⁰¹TlCl improves image quality as well as lowers radiation exposure.     

Different hypersensitivities against homologous proteins of MGL_1304 in patients with atopic dermatitis

Background

Atopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malassezia globosa was identified as the major histamine releasing antigen in human sweat.

Radical Polymerization and Copolymerization of 12‐[(N‐Methacryloyl)carbamoyloxy]octadecanoic Acid

Radical polymerization of 12‐[(N‐methacryloyl)carbamoyloxy] octadecanoic acid ( 1 ) was kinetically and ESR spectroscopically investigated in acetone, using dimethyl 2,2′‐azobisisobutyrate ( 2 ) as initiator. The polymerization rate (R_p) is given by R_p = k [2]^0.7[1]^1.4 at 50°C. Propagating poly( 1 ) radical was observed as a 13‐lines spectrum by ESR under the actual polymerization conditions. The ESR‐determined k_p values (1.8–7.9 L/mol·s) are much lower than those of usual methacrylate monomers. The rate constant (k_t) of termination was determined to be k_t = 1.0–2.7·10⁴ L/mol·s from decay curve of the propagating radical. The Arrhenius plots of k_p and k_t gave the activation energies of propagation (63 kJ/mol) and termination (24 kJ/mol). A significant solvent effect was observed on the radical polymerization of 1 . The copolymerizations of 1 with styrene(St) and acrylonitrile were examined at 50°C. Copolymerization parameters obtained for the 1  (M₁)/St (M₂) system are as follows; r₁ = 0.73, r₂ = 0.57, Q₁ = 0.83, and e₁ = 0.13.     

Takayasu arteritis developing during treatment of ulcerative colitis with infliximab

A 22-year-old female with ulcerative colitis that was successfully treated with infliximab (IFX), and remained stable following tapered discontinuation of prednisolone, developed anterior neck pain and elevation of C-reactive protein following her fourth administration of IFX. She was diagnosed with Takayasu arteritis (TA) based on neck ultrasound and computed tomography angiography. This is the first report describing the development of TA during treatment of UC with IFX.     

Dose‐dependent effect of stored‐blood transfusions on recipient red blood cell indices,deformability and density

We prospectively studied the dose‐dependent effect of transfused stored red blood cells (RBCs) on recipient RBC indices, deformability and cell density in 10 patients administered stored RBCs for blood transfusion during general surgery. There were dose‐dependent decreases in mean corpuscular volume and increases in mean corpuscular haemoglobin concentration after completion of 4‐ and 6‐unit stored RBC transfusions. The amount of dense populations increased proportionately with the amount of stored RBCs transfused. The maximal deformability index value was significantly and dose‐dependently decreased, suggesting that hemodynamic blood flow, especially the microcirculation may be impaired in patients who receive large amounts of stored RBCs.     

A mutation database for amyotrophic lateral sclerosis

An amyotrophic lateral sclerosis (ALS) mutation database has been constructed as a publicly accessible online resource for recording the nucleotide and amino acid variants identified in genes associated with ALS, along with corresponding clinical conditions. The database currently consists of more than 600 entries, including about 180 unique variants found in 25 disease‐causative or disease‐related genes. In addition to published data collected from literature, novel variants identified by microarray resequencing in our laboratory are incorporated into the database. Every reported gene has a respective page that provides information on its variation positions with various statistics, clinical characteristics, and primary references, as well as gene‐sequence and protein‐structure information that will assist in assessing variation significance. Users can access a homology search function to find variations in arbitrary sequences of interest and to check if they have already been described in the database. This database is expected to fulfill an essential need in terms of integrating comprehensive information on genetic and clinical data related to ALS, which will subsequently deepen our understanding of the possible mechanisms of the disease, as well as help with the clinical practice and treatment of ALS. The database is accessible at: https://reseq.lifesciencedb.jp/resequence/SearchDisease.do?targetId=1 . Data submission is open to all researchers and is highly encouraged. Hum Mutat 31:1003–1010, 2010. © 2010 Wiley‐Liss, Inc.     

Role of ornithine decarboxylase antizyme inhibitor in vivo

Ornithine decarboxylase (ODC) antizyme inhibitor (AZI) has been shown to regulate ODC activity in cell cultures. However, its biological functions in an organism remain unknown. An embryonic stem (ES) cell clone was established, in which the Azin1 gene was disrupted by the gene trap technique. To identify the function of Azin1 gene in vivo , a mutant mouse line was generated using these trapped ES cells. Homozygous mutant mice died at P0 with abnormal liver morphology. Further analysis indicated that the deletion of Azin1 in homozygous mice resulted in the degradation of ODC, and reduced the biosynthesis of putrescine and spermidine. Our results thus show that AZI plays an important role in regulating the levels of ODC, putrescine and spermidine in mice, and is essential for the survival of mice.     

A case of WHIM syndrome associated with diabetes and hypothyroidism

Abstract: The WHIM syndrome is a rare immunological disorder characterized by warts, hypogammaglobulinemia, infections, and myelokathexis. We hypothesized that immunological or genetic mechanisms may link WHIM syndrome and type 1 diabetes. We report that the young girl with WHIM syndrome developed diabetes and transient hypothyroidism. A nonsense mutation (C→T) truncating the CXC chemokine receptor 4 (CXCR4) C-terminal cytoplasmic tail domain occurred at nucleotide position 1000(R334X) of the CXCR4 gene in one allele of the patient was identified, and the person was diagnosed as having WHIM syndrome. Recent observation suggested that the CXCR4, a G-protein-coupled receptor with a unique ligand, CXCL12, might be involved in the pathogenesis for type 1 diabetes. Taken into consideration the concurrent prevalence of the two disorders and the speculated common pathogenesis associated with the CXCR4, our patient may enable us to understand the genetic damage related to accelerated apoptosis.