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991.
992.
Tubulo-interstitial fibrosis is a common, destructive endpoint for a variety of kidney diseases. Fibrosis is well correlated with the loss of kidney function in both humans and rodents. The identification of modulators of fibrosis could provide novel therapeutic approaches to reducing disease progression or severity. Here, we show that the peptidyl-prolyl isomerase Pin1 is an important molecular contributor that facilitates renal fibrosis in a well-characterized animal model. While wild-type mice fed a high phosphate diet (HPD) for 8–12 weeks developed calcium deposition, macrophage infiltration and extracellular matrix (ECM) accumulation in the kidney interstitium, Pin1 null mice showed significantly less pathology. The serum Pi in both WT and KO mice were significantly increased by the HPD, but the serum Ca was slightly decreased in KO compared to WT. In addition, both WT and KO HPD mice had less weight gain but exhibited normal organ mass (kidney, lung, spleen, liver and heart). Unexpectedly, renal function was not initially impaired in either genotype irrespective of the HPD. Our results suggest that diet containing high Pi induces rapid renal fibrosis before a significant impact on renal function and that Pin1 plays an important role in the fibrotic process. 相似文献
993.
Kazuhiro Takimoto Motoko Taharaguchi Koji Sakai Hirotaka Takagi Yukinobu Tohya Yasuko K Yamada 《Experimental Animals》2013,62(3):237-245
We evaluated the in vitro efficacy of weak acid hypochlorous solution
(WAHS) against murine norovirus (MNV) by plaque assay and compared the efficacy with
diluted NaOCl (Purelox) and 70% ethanol. WAHS was as effective as 70% ethanol and diluted
Purelox for 0.5-min reactions. For 0.5-min reactions in the presence of mouse feces
emulsion, the efficacy of WHAS and 1:600 diluted Purelox was decreased, reducing the virus
titers by 2.3 and 2.6 log10, respectively, while 70% ethanol reduced the titer
by more than 5 log10. However, WAHS showed more than 5 log10
reductions for the 5-min reaction even in the presence of feces emulsion. Since WAHS
showed enough efficacy in inactivating MNV in vitro, we tried to
eliminate MNV from MNV-infected mice by substituting WAHS for their drinking water.
However, MNV was found to be positive in feces of mice drinking WAHS by an RT-nested PCR
and plaque assay. To investigate whether hypochlorite-based disinfectants could prevent
infection of a mouse with MNV, WAHS or 1:6,000 diluted Purelox was substituted for the
drinking water of mice for 2 or 4 weeks, and then the mice were placed in a cage with an
MNV-infected mouse. The supply of disinfectants was continued after cohabitation, but MNV
was detected in the feces of all the mice at 1 week after cohabitation. In this study, we
tried to eliminate and prevent MNV infection from mice by supplying hypochlorite-based
disinfectants as an easy and low-cost method. Unfortunately, drinking disinfectants was
ineffective, so it is important to keep the facility environment clean by use of effective
disinfectants. Also, animals introduced into facilities should be tested as MNV free by
quarantine and periodically confirmed as MNV free by microbiological monitoring. 相似文献
994.
Yuichi Yoshimura Fumitaka Kano Shuichi Miyazaki Noriyuki Ashida Shinji Sakata Kazuhiro Haraguchi 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):305-324
Abstract 2′-Deoxy-, 2′-bromo-, and arabino-1′-C-cyano-pyrimidine nucleosides were synthesized from O2 ,2′-cyclouridine. Incorporation of cyano group at the anomeric position was achieved by treatment of 1′,2′-unsaturated uridine with NBS in the presence of pivalic acid followed by TMS-cyanide and stannic chloride. Antineoplastic and antiviral activities of those compounds are also discussed. 相似文献
995.
Kazuhiro Ozawa Ryoya Niki Shunrokuro Arima 《Bioscience, biotechnology, and biochemistry》2013,77(11):3123-3129
The effects of caseins on the rheological properties of κ-carrageenan-calcium gel was investigated by measuring the gel breaking strength. The existence of β-casein in the system promoted the gelation of κ-carrageenan in the presence of calcium ion. Beta-casein increased the strength of calcium gels of κ-carrageenan with increasing NaCl concentration up to 80 mM and strengthened the κ-carrageenan-calcium gel at neutral pH. The values obtained from the slopes of the logarithmic plots of the gel strength versus concentration were 2.15 for κ-carrageenan gel and 2.27 for a β-casein-κcarrageenan mixture gel, suggesting that β-casein may participate in the gelation of κ-carrageenan through the mediation of calcium ions. 相似文献
996.
Tetsuyoshi Inoue Ichiro Tanimoto Hiroyuki Ohta Keijiro Kato Yoji Murayama Kazuhiro Fukui 《Microbiology and immunology》1998,42(4):253-258
Fimbriae preparation from Actinobacillus actinomycetemcomitans was found to contain an abundant low-molecular-weight protein (termed Flp) with an apparent molecular mass of approximately 6.5 kDa, in addition to a small amount of 54-kDa protein. Immunogold electron microscopy localized the Flp protein at the bacterial fimbriae but not at the cell surface. The DNA fragment including the flp gene was cloned from A. actinomycetemcomitans 304-a and its nucleotide sequence was determined. An open reading frame of the flp gene was composed of 225 bp encoding a protein of 75 amino acids. Comparison of the translated amino acid sequence with the sequence of native Flp determined by Edman degradation indicated that the N-terminal part of 26 amino acids is leader peptide. The N-terminal sequence of mature Flp exhibited some similarity to type-IV pilin. Furthermore, the processing site of premature Flp is also similar to that of type-IV prepilin, and a gene encoding a protein homologous to type-IV prepilin-like protein leader peptidase was found downstream of the flp gene. These findings indicate that Flp is the major component protein of A. actinomycetemcomitans fimbriae. 相似文献
997.
Kazuhiro Kitajima Utaru Tanaka Yoshiko Ueno Tetsuo Maeda Yuko Suenaga Satoru Takahashi Masashi Deguchi Yoshiya Miyahara Yasuhiko Ebina Hideto Yamada Masakatsu Tsurusaki Yukihisa Tamaki Kazuro Sugimura 《PloS one》2015,10(1)
Background and Purpose
To investigate the diagnostic performance of diffusion-weighted imaging (DWI) and contrast-enhanced imaging in combination with T2-weighted imaging (T2WI) for magnetic resonance imaging (MRI) evaluation of intrapelvic recurrence of gynecological malignancies.Materials and Methods
Sixty-two patients with suspected intrapelvic recurrence of gynecological malignancies underwent pelvic MRI including T2WI DWI, and contrast-enhanced imaging. Diagnostic performance for detection of local recurrence, pelvic lymph node and bone metastases, and peritoneal lesions was evaluated by consensus reading of two experienced radiologists using a 5-point scoring system, and compared among T2WI with unenhanced T1-weighted imaging (T1WI) (protocol A), a combination of protocol A and DWI (protocol B), and a combination of protocol B and contrast-enhanced imaging (protocol C). Final diagnoses were obtained by histopathological examinations, radiological imaging and clinical follow-up for at least 6 months. Receiver operating characteristic (ROC) analysis and McNemar test were employed for statistical analysis.Results
Locally recurrent disease, lymph node recurrence, peritoneal dissemination and bone metastases were present in 48.4%, 29.0%, 16.1%, and 6.5% of the patients, respectively. The patient-based sensitivity, specificity, accuracy, and area under the ROC curve (AUC) for detection of intrapelvic recurrence were 55.0, 81.8, 64.5% and 0.753 for protocol A, 80.0, 77.3, 79.0% and 0.838 for protocol B, and 80.0, 90.9, 83.9% and 0.862 for protocol C, respectively. The sensitivity, accuracy, and AUC were significantly better for protocols B and C than for protocol A (p<0.001). There was no significant difference between protocols B and C.Conclusion
MRI using a combination of DWI and T2WI gives comparatively acceptable results for assessment of intrapelvic recurrence of gynecological malignancies. 相似文献998.
Makito Hirano Wataru Satake Kenji Ihara Ikuya Tsuge Shuji Kondo Ken Saida Hiroyuki Betsui Kazuhiro Okubo Hikaru Sakamoto Shuichi Ueno Yasushi Ikuno Ryu Ishihara Hiromi Iwahashi Mitsuru Ohishi Toshiyuki Mano Toshihide Yamashita Yutaka Suzuki Yusaku Nakamura Susumu Kusunoki Tatsushi Toda 《PloS one》2015,10(9)
Bardet-Biedl syndrome (BBS) is an autosomal recessive disorder characterized by central obesity, mental impairment, rod-cone dystrophy, polydactyly, hypogonadism in males, and renal abnormalities. The causative genes have been identified as BBS1-19. In Western countries, this disease is often reported, but remains undiagnosed in many patients until later in life, while only a few patients with no mutations identified have been reported in Japan. We thus conducted the first nationwide survey of BBS in Japan by sending questionnaires to 2,166 clinical departments with board-certified specialists and found 7 patients with clinically definite BBS. We performed exome analyses combined with analyses of mRNA and protein in these patients. We identified 2 novel mutations in the BBS5 gene (p.R89X and IVS7-27 T>G) in 2 sibling patients. The latter mutation that resided far from the authentic splicing site was associated with skipping of exon 8. We also found 3 previously reported mutations in the BBS2 (p.R413X and p.R480X) and BBS7 (p.C243Y) genes in 2 patients. To our knowledge, a nationwide survey of BBS has not been reported in any other country. In addition, this is the first study to identify genetic alterations in Japanese patients with BBS. Our results indicate that BBS in Japan is genetically heterogeneous and at least partly shares genetic features with BBS in other countries. 相似文献
999.
Takashi Ueyama Tomohiro Donishi Satoshi Ukai Yuta Yamamoto Takuya Ishida Shunji Tamagawa Muneki Hotomi Kazuhiro Shinosaki Noboru Yamanaka Yoshiki Kaneoke 《PloS one》2015,10(9)
Tinnitus is the perception of phantom sound without an external auditory stimulus. Using neuroimaging techniques, such as positron emission tomography, electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI), many studies have demonstrated that abnormal functions of the central nervous system are closely associated with tinnitus. In our previous research, we reported using resting-state fMRI that several brain regions, including the rectus gyrus, cingulate gyrus, thalamus, hippocampus, caudate, inferior temporal gyrus, cerebellar hemisphere, and medial superior frontal gyrus, were associated with tinnitus distress and loudness. To reconfirm these results and probe target regions for repetitive transcranial magnetic stimulation (rTMS), we investigated the regional cerebral blood flow (rCBF) between younger tinnitus patients (<60 years old) and the age-matched controls using single-photon emission computed tomography and easy Z-score imaging system. Compared with that of controls, the rCBF of tinnitus patients was significantly lower in the bilateral medial superior frontal gyri, left middle occipital gyrus and significantly higher in the bilateral cerebellar hemispheres and vermis, bilateral middle temporal gyri, right fusiform gyrus. No clear differences were observed between tinnitus patients with normal and impaired hearing. Regardless of the assessment modality, similar brain regions were identified as characteristic in tinnitus patients. These regions are potentially involved in the pathophysiology of chronic subjective tinnitus. 相似文献
1000.
Satoshi Kume Masanori Yamato Yasuhisa Tamura Guanghua Jin Masayuki Nakano Yukiharu Miyashige Asami Eguchi Yoshiyuki Ogata Nobuhito Goda Kazuhiro Iwai Emi Yamano Yasuyoshi Watanabe Tomoyoshi Soga Yosky Kataoka 《PloS one》2015,10(3)
In the present study, prior to the establishment of a method for the clinical diagnosis of chronic fatigue in humans, we validated the utility of plasma metabolomic analysis in a rat model of fatigue using capillary electrophoresis-mass spectrometry (CE-MS). In order to obtain a fatigued animal group, rats were placed in a cage filled with water to a height of 2.2 cm for 5 days. A food-restricted group, in which rats were limited to 10 g/d of food (around 50% of the control group), was also assessed. The food-restricted group exhibited weight reduction similar to that of the fatigued group. CE-MS measurements were performed to evaluate the profile of food intake-dependent metabolic changes, as well as the profile in fatigue loading, resulting in the identification of 48 metabolites in plasma. Multivariate analyses using hierarchical clustering and principal component analysis revealed that the plasma metabolome in the fatigued group showed clear differences from those in the control and food-restricted groups. In the fatigued group, we found distinctive changes in metabolites related to branched-chain amino acid metabolism, urea cycle, and proline metabolism. Specifically, the fatigued group exhibited significant increases in valine, leucine, isoleucine, and 2-oxoisopentanoate, and significant decreases in citrulline and hydroxyproline compared with the control and food-restricted groups. Plasma levels of total nitric oxide were increased in the fatigued group, indicating systemic oxidative stress. Further, plasma metabolites involved in the citrate cycle, such as cis-aconitate and isocitrate, were reduced in the fatigued group. The levels of ATP were significantly decreased in the liver and skeletal muscle, indicative of a deterioration in energy metabolism in these organs. Thus, this comprehensive metabolic analysis furthered our understanding of the pathophysiology of fatigue, and identified potential diagnostic biomarkers based on fatigue pathophysiology. 相似文献