Publications by authors named "Akihiko Arakawa"

Quinone outside inhibitors (QoIs), which inhibit the mitochondrial respiratory system by binding to the Qo site of Complex III in fungi, are widely used as pesticides with broad spectrum antifungal activity. However, excessive use of QoIs leads to pesticide resistance through mutation of amino acid residues in the Qo site. Recently, metyltetraprole, a novel QoI that is effective against wild-type and resistant mutant fungi, was developed.

View Article and Find Full Text PDF

The Hsp90 molecular chaperone and its Cdc37 cochaperone help stabilize and activate more than half of the human kinome. However, both the mechanism by which these chaperones assist their "client" kinases and the reason why some kinases are addicted to Hsp90 while closely related family members are independent are unknown. Our structural understanding of these interactions is lacking, as no full-length structures of human Hsp90, Cdc37, or either of these proteins with a kinase have been elucidated.

View Article and Find Full Text PDF

Sufficient colonic dilation is important when using CT colonography (CTC) for colorectal cancer screening. We investigated the effect of antispasmodic agents and the patient body habitus on the degree of colonic dilation in screening CTC.We assessed the effect of clinical characteristics [age, gender, body mass index (BMI), and the presence of diverticula] and the use of antispasmodics on colonic distention in 140 patients who underwent CTC for colorectal cancer screening.

View Article and Find Full Text PDF
Article Synopsis
  • A 60-year-old man with advanced rectal cancer underwent chemoradiotherapy and showed initial tumor shrinkage and symptom resolution.
  • After suspecting remnant cancer, he started a new chemotherapy regimen, mFOLFOX6, but had to stop due to side effects.
  • Ultimately, a complete clinical and pathological response was achieved with additional S-1 treatment over a year, and he has remained cancer-free for 6 years, indicating non-surgical treatment can be effective for this condition.
View Article and Find Full Text PDF

Purpose: The purpose of our study was to evaluate the morphology of the lumbosacral spine, i.e. the dura and vertebral body shape, of Japanese patients with Marfan syndrome (MFS) by comparing it with sex- and age-matched controls.

View Article and Find Full Text PDF

Discs large homolog 1 (DLG1/SAP97) is involved in the development and regulation of neuronal and immunological synapses. DLG1 is a member of the membrane associated guanylate kinase (MAGUK) family of proteins, which function as molecular scaffolds. The C-terminal guanylate kinase (GK) domain of DLG1 binds peptides with a phosphorylated serine residue.

View Article and Find Full Text PDF

The molecular chaperone 70-kDa heat shock protein (Hsp70) is driven by ATP hydrolysis and ADP-ATP exchange. ADP dissociation from Hsp70 is reportedly slow in the presence of inorganic phosphate (P(i) ). In this study, we investigated the interaction of Hsp70 and its nucleotide-binding domain (NBD) with ADP in detail, by isothermal titration calorimetry measurements and found that Mg(2+) ion dramatically elevates the affinity of Hsp70 for ADP.

View Article and Find Full Text PDF

A 65-year-old man suffering from acute pancreatitis underwent MRI scanning, which revealed a low signal on the T1 and T2 sequences, and hypovascularity in arterial phase in the head of the pancreas. This corresponded to the area showing the absence of the lower common bile duct. FDG-PET was highly suggestive of pancreatic cancer (T4N1M0, Stage IVa) with lymph node metastasis.

View Article and Find Full Text PDF

ADP-ATP exchange by the molecular chaperone Hsp70 is enhanced by several cochaperones. BAG5 consists of five BAG domains and associates with the nucleotide-binding domain (NBD) of Hsp70. The overexpression of BAG5 in the cytosol reportedly disturbs Hsp70-mediated protein refolding and induces Parkinson's disease.

View Article and Find Full Text PDF

The 70 kDa heat-shock proteins (Hsp70s) are highly conserved chaperones that are involved in several cellular processes, such as protein folding, disaggregation and translocation. In this study, the crystal structures of the human Hsp70 nucleotide-binding domain (NBD) fragment were determined in the nucleotide-free state and in complex with adenosine 5'-(beta,gamma-imido)triphosphate (AMPPNP). The structure of the nucleotide-free NBD fragment is similar to that of the AMPPNP-bound NBD fragment and is designated as the ;closed form'.

View Article and Find Full Text PDF

Purpose: The purpose of this study was to compare the performance of in-phase and opposed-phase gradient-recalled echo (GRE) pulse sequences in paramagnetic contrast-enhanced magnetic resonance (MR) imaging of hepatocellular carcinomas (HCCs) during the hepatic arterial phase.

Material And Methods: Thirty-four patients with 84 lesions with known or suspected HCCs, nine of whom had a fatty liver, were examined with double-echo GRE techniques under 1.5T before and 30 s after injection of gadopentenate dimeglumine at a dose of 0.

View Article and Find Full Text PDF

Purpose: To compare enhancement of the aorta, portal vein, liver, and tumor with contrast medium of a higher iodine concentration to that with one of a standard iodine concentration for liver dynamic CT within the same patient with known liver cirrhosis and hepatocellular carcinoma (HCC).

Materials And Methods: Fifty-three patients with known cirrhosis and HCC underwent repeat computed tomographic (CT) examinations within three months, the first with either 300 (n=26) or 370 mgI/ml (n=27) of nonionic contrast material. In the second examination, only concentration was altered.

View Article and Find Full Text PDF

The aim of this study was to evaluate the clinical conditions of gastric diverticulum. Fifty-four patients with gastric diverticulum (20 men and 34 women among 34,314 patients who underwent medical check-ups) were evaluated on indirect radiographs, for an incidence of 0.16% among the total number of examined cases, a rate lower than that of previous reports.

View Article and Find Full Text PDF