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81.
W Mai L Barraud L Lefrancois J Y Scoazec S Guerret D Vray P Merle L Vitvitski-Trepo C Trepo M F Janier 《Liver international》2004,24(6):651-657
AIMS: To evaluate trans-abdominal ultrasound for the detection of Hepatocellular carcinoma (HCC) in a bitrasgenic murine (X/myc) model using a commercially available high-frequency ultrasound unit. METHODS: Sixty-one female animals were included in this study. These animals were submitted to a single ultrasound examination of the liver under general anesthesia (isoflurane), and then euthanized. Results of ultrasound were compared with necropsy and histopathology. RESULTS: The lesions demonstrated a fairly consistent aspect (oval- or round-shaped, well-defined hypoechoic homogeneous lesions), and lesions as small as 2 mm were identified. For detection of hepatic nodules per mouse the sensitivity was 75%, the specificity was 100% and the accuracy was 88.5%. For detection of hepatic focal lesions per lesions the overall sensitivity was 60%, the specificity was 97%, and the accuracy was 75.9%. Contrast-enhanced harmonic ultrasound imaging did not improve the identification of the lesions in our experimental conditions. CONCLUSION: High-frequency ultrasound appears to be an efficient tool allowing new possibilities to use this animal model and evaluate new therapies in longitudinal studies, which are much more powerful. 相似文献
82.
Atsushi Morita Takashi Enokizono Tatsuyuki Ohto Mai Tanaka Shiena Watanabe Yui Takada Kazuhiro Iwama Takeshi Mizuguchi Naomichi Matsumoto Masashi Morita Shigeo Takashima Nobuyuki Shimozawa Hidetoshi Takada 《Brain & development》2021,43(3):475-481
Peroxisomal acyl-CoA oxidase (ACOX1) deficiency is a rare autosomal recessive single enzyme deficiency characterized by hypotonia, seizures, failure to thrive, developmental delay, and neurological regression starting from approximately 3 years of age.Here, we report two siblings with ACOX1 deficiency born to non-consanguineous Japanese parents. They showed mild global developmental delay from infancy and began to regress at 5 years 10 months and 5 years 6 months of age respectively. They gradually manifested with cerebellar ataxia, dysarthria, pyramidal signs, and dysphasia. Brain MRI revealed T2 high-intensity areas in the cerebellar white matter, bilateral middle cerebellar peduncle, and transverse tracts of the pons, followed by progressive atrophy of these areas.Intriguingly, the ratios of C24:0, C25:0, and C26:0 to C22:0 in plasma, which usually increase in ACOX1 deficiency were within normal ranges in both patients. On the other hand, whole exome sequencing revealed novel compound heterozygous variants in ACOX1: a frameshift variant (c.160delC:p.Leu54Serfs*18) and a missense variant (c.1259 T > C:p.Phe420Ser). The plasma concentration of individual very long chain fatty acids (C24:0, C25:0, and C26:0) was elevated, and we found that peroxisomes in fibroblasts of the patients were larger in size and fewer in number as previously reported in patients with ACOX1 deficiency. Furthermore, the C24:0 β-oxidation activity was dramatically reduced.Our findings suggest that the elevation of individual plasma very long chain fatty acids concentration, genetic analysis including whole exome analysis, and biochemical studies on the patient’s fibroblasts should be considered for the correct diagnosis of ACOX1 deficiency. 相似文献
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Xin Zhou Zhuo Huang Jun Zhang Jia-Liang Chen Pei-Wen Yao Chun-Lin Mai Jie-Zhen Mai Hui Zhang Xian-Guo Liu 《神经科学通报》2021,37(1):55
Antineoplastic drugs such as oxaliplatin (OXA) often induce memory and emotional deficits. At present, the mechanisms underlying these side-effects are not fully understood, and no effective treatment is available. Here, we show that the short-term memory deficits and anxiety-like and depression-like behaviors induced by intraperitoneal injections of OXA (4 mg/kg per day for 5 consecutive days) were accompanied by synaptic dysfunction and downregulation of the NR2B subunit of N-methyl-D-aspartate receptors in the hippocampus, which is critically involved in memory and emotion. The OXA-induced behavioral and synaptic changes were prevented by chronic oral administration of magnesium-L-threonate (L-TAMS, 604 mg/kg per day, from 2 days before until the end of experiments). We found that OXA injections significantly reduced the free Mg2+ in serum and cerebrospinal fluid (from ~ 0.8 mmol/L to ~ 0.6 mmol/L). The Mg2+ deficiency (0.6 mmol/L) upregulated tumor necrosis factor (TNF-α) and phospho-p65 (p-p65), an active form of nuclear factor-kappaB (NF-κB), and downregulated the NR2B subunit in cultured hippocampal slices. Oral L-TAMS prevented the OXA-induced upregulation of TNF-α and p-p65, as well as microglial activation in the hippocampus and the medial prefrontal cortex. Finally, similar to oral L-TAMS, intracerebroventricular injection of PDTC, an NF-κB inhibitor, also prevented the OXA-induced memory/emotional deficits and the changes in TNF-α, p-p65, and microglia. Taken together, the activation of TNF–α/NF–κB signaling resulting from reduced brain Mg2+ is responsible for the memory/emotional deficits induced by OXA. Chronic oral L-TAMS may be a novel approach to treating chemotherapy-induced memory/emotional deficits.Electronic supplementary materialThe online version of this article (10.1007/s12264-020-00563-x) contains supplementary material, which is available to authorized users. 相似文献
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Mai Hashimoto Kazuaki Taguchi Shuhei Imoto Keishi Yamasaki Hiroaki Mitsuya Masaki Otagiri 《Journal of infection and chemotherapy》2021,27(5):702-706
IntroductionThe novel nucleoside analog, 4′-cyano-2′-deoxyguanosine (CdG), possesses inhibitory activity against both the wild-type and resistant hepatitis B virus. Since the dosage of the currently available nucleoside analog preparations needs to be adjusted, depending on renal function, we investigated the effect of renal dysfunction on the pharmacokinetics of CdG in a rat model of chronic kidney disease (CKD).MethodsCKD model rats were either intravenously or orally administered CdG at a dose of 1 mg/kg. The concentration of CdG in plasma, organs (liver and kidney) and urine samples were determined by means of a UPLC system interfaced with a TOF-MS system.ResultsFollowing intravenous administration, the plasma retention of CdG was prolonged in CKD model rats compared to healthy rats. In addition, the clearance of CdG was well correlated with plasma creatinine levels in CKD model rats. Similar to the results for intravenous administration, the plasma concentration profiles of CdG after oral administration were also found to be much higher in CKD model rats than in healthy rats. However, the results for the organ distribution and urinary excretion of CdG, the profiles of which were similar to that of healthy rats, indicated that CdG did not accumulate to a significant extent in the body.ConclusionThe extent of renal dysfunction has a direct influence on the pharmacokinetics (plasma retention) of CdG without a significant accumulation, indicating that the dosage of CdG will be dependent on the extent of renal function. . 相似文献
88.
Mai Uchida Joseph Biederman John D. E. Gabrieli Jamie Micco Carlo de Los Angeles Ariel Brown Tara Kenworthy Elana Kagan Susan Whitfield-Gabrieli 《Social cognitive and affective neuroscience》2015,10(12):1738-1748
This study investigated the neural basis of individual variation in emotion regulation, specifically the ability to reappraise negative stimuli so as to down-regulate negative affect. Brain functions in young adults were measured with functional Magnetic Resonance Imaging during three conditions: (i) attending to neutral pictures; (ii) attending to negative pictures and (iii) reappraising negative pictures. Resting-state functional connectivity was measured with amygdala and dorsolateral prefrontal cortical (DLPFC) seed regions frequently associated with emotion regulation. Participants reported more negative affect after attending to negative than neutral pictures, and less negative affect following reappraisal. Both attending to negative vs neutral pictures and reappraising vs attending to negative pictures yielded widespread activations that were significantly right-lateralized for attending to negative pictures and left-lateralized for reappraising negative pictures. Across participants, more successful reappraisal correlated with less trait anxiety and more positive daily emotion, greater activation in medial and lateral prefrontal regions, and lesser resting-state functional connectivity between (a) right amygdala and both medial prefrontal and posterior cingulate cortices, and (b) bilateral DLPFC and posterior visual cortices. The ability to regulate emotion, a source of resilience or of risk for distress, appears to vary in relation to differences in intrinsic functional brain architecture. 相似文献
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Mai Inoue Masaya Sasaki Azusa Takaoka Mika Kurihara Hiromi Iwakawa Shigeki Bamba Hiromitsu Ban Akira Andoh 《Journal of Clinical Biochemistry and Nutrition》2015,56(3):215-219
We investigated the changes in energy expenditure during induction therapy in patients with severe or moderate ulcerative colitis. Thirteen patients (10 men, 3 women; mean age, 36.5 years) with ulcerative colitis admitted to the Shiga University Hospital were enrolled in this study. We measured the resting energy expenditure and respiratory quotients of these patients before and after induction therapy with indirect calorimetry. We analyzed the changes of nutritional status and serum inflammatory cytokine levels and also evaluated the relationship between energy metabolism and disease activity by using the Seo index and Lichtiger index. The resting energy expenditure was 26.3 ± 3.8 kcal/kg/day in the active stage and significantly decreased to 23.5 ± 2.4 kcal/kg/day after induction therapy (p<0.01). The resting energy expenditure changed in parallel with the disease activity index and C-reactive protein and inflammatory cytokine levels. The respiratory quotient significantly increased after induction therapy. Thus, moderate to severe ulcerative colitis patients had a hyper-metabolic status, and the energy metabolism of these patients significantly changed after induction therapy. Therefore, we recommend that nutritional management with 30–34 kcal/kg/day (calculated as measured resting energy expenditure × activity factor, 1.3) may be optimal for hospitalized ulcerative colitis patients. 相似文献