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61.
We report a patient with hemiparkinsonism associated with unilateral striatal necrosis of the contralateral side. The patient was an 18-year-old woman who had a two-month-history of difficulty in executing skilled movements with her right upper extremity. Neurological examination revealed that she had cogwheel rigidity and bradykinesia in her right upper and lower extremities. MRI revealed a well-delineated low signal intensity in T1-weighted and high signal intensity in T2-weighted images in the region of the putamen on the left side. Her laboratory data were unremarkable and mitochondrial gene mutation studies revealed no abnormality. It is extremely rare to encounter a case of parkinsonism associated with unilateral striatal necrosis.  相似文献   
62.
Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches, to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (P450) probe substrates, inhibitors and inducers and for the development of classification systems to improve the communication of risk to health care providers and to patients. While existing guidances cover mainly P450-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently, and should also be addressed. This article was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers.  相似文献   
63.
BACKGROUND: Hepatic artery thrombosis (HAT) remains an important cause of graft loss after liver transplantation. Emergency rearterialization methods are limited in cases of living-related liver transplantation in which the graft hepatic artery is thin and short. CASE: A 19-year-old woman who underwent living-related liver transplantation for biliary atresia developed HAT on the 4th postoperative day. During the emergency laparotomy the recipient hepatic artery was found to be too short to anastomose, so the recipient's right gastroepiploic artery was anastomosed to the graft hepatic artery. The patient is now alive and well 6 months after reoperation, and she has experienced no further episode of HAT. CONCLUSION: The right gastroepiploic artery can be used easily and safely for hepatic graft revascularization without causing ischemia of the stomach. An additional skin incision is not required, and the artery is long enough to anastomose to the graft artery directly. The method of hepatic graft rearterialization described here is an important option for patients who undergo living-related or split liver transplantation.  相似文献   
64.
Bortezomib [N-(2,3-pyrazine)carbonyl-L-phenylalanine-L-leucine boronic acid] is a potent first-in-class dipeptidyl boronic acid proteasome inhibitor that was approved in May 2003 in the United States for the treatment of patients with relapsed multiple myeloma where the disease is refractory to conventional lines of therapy. Bortezomib binds the proteasome via the boronic acid moiety, and therefore, the presence of this moiety is necessary to achieve proteasome inhibition. Metabolites in plasma obtained from patients receiving a single intravenous dose of bortezomib were identified and characterized by liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Metabolite standards that were synthesized and characterized by LC/MS/MS and high field nuclear magnetic resonance spectroscopy (NMR) were used to confirm metabolite structures. The principal biotransformation pathway observed was oxidative deboronation, most notably to a pair of diastereomeric carbinolamide metabolites. Further metabolism of the leucine and phenylalanine moieties produced tertiary hydroxylated metabolites and a metabolite hydroxylated at the benzylic position, respectively. Conversion of the carbinolamides to the corresponding amide and carboxylic acid was also observed. Human liver microsomes adequately modeled the in vivo metabolism of bortezomib, as the principal circulating metabolites were observed in vitro. Using cDNA-expressed cytochrome P450 isoenzymes, it was determined that several isoforms contributed to the metabolism of bortezomib, including CYP3A4, CYP2C19, CYP1A2, CYP2D6, and CYP2C9. The development of bortezomib has provided an opportunity to describe the metabolism of a novel boronic acid pharmacophore.  相似文献   
65.
Constitutively active internal tandem duplication (ITD) in the juxtamembrane domain of Fms-like tyrosine kinase 3 (FLT3), a type III receptor tyrosine kinase, is the most common molecular defect associated with acute myeloid leukemia. Its presence confers a poor outcome in patients with acute myeloid leukemia who receive conventional chemotherapy. FLT3-ITD has therefore been considered to be an attractive molecular target for a novel therapeutic modality. We describe here the identification and characterization of Ki23819 as a novel FLT3 inhibitor. Ki23819 suppressed proliferation and induced apoptosis of FLT3-ITD-expressing human leukemia cell lines. The growth-inhibitory effect of Ki23819 on MV4-11 cells was superior to that of SU11248, another FLT3 inhibitor (IC(50)<1 vs 3-10 nM). Ki23819 inhibited the autophosphorylation of FLT3-ITD more efficiently than that of wild-type FLT3. FLT3-ITD-dependent activation of the downstream signaling proteins ERK and STAT5 was also inhibited within similar concentration ranges. Thus, Ki23819 is a potent in vitro inhibitor of FLT3.  相似文献   
66.
AIM: The significance of MUC 1 expression in the gallbladder tissues in relation to cancer and non-cancer disease is not well understood. The aim of this study was to clarify the significance of MUC 1 expression. MATERIALS AND METHODS: A monoclonal antibody (CA 15--3; DF 3) was applied to stain MUC 1 core protein in surgical specimens. RESULTS: MUC 1 expression is significantly higher (p<0.0001) in gallbladder cancer (69/88) compare to non-cancerous tissue, while, very trace in normal and inflammatory tissues. The expression rate was significantly lower (p<0.0001) when the cancer did not penetrate the mucosal layer than when cancers did penetrate this layer. The MUC 1 expression rate was (4/14) in T1 tumours, (11/14) in T4, (40/45) in T3, and (14/15) in T2, respectively. Every cell of normal and inflammatory mucosa, and T1 cancers had the polarized pattern. The depolarized pattern was dominant in cancer cells from the advanced tumours of T2, T3 and T4. That is, (45/74) of cancer cells from the mucosal layer and (58/74) of penetrating cancer cells in submucosal layer had the depolarized pattern. There was no significant correlation of MUC 1 expression rate and staining pattern with cancer differentiation and microscopic venous invasion. On the other hand, lymphatic vessel invasion was significantly correlated with the staining pattern but not with expression rate. CONCLUSION: MUC 1 core protein expression rate and pattern are suggesting that MUC 1 core protein would be a marker of malignant transformation of gallbladder epithelium and its depolarized expression would also be a marker of invasion of gallbladder cancer.  相似文献   
67.
Trousseau syndrome-related cerebral infarction rarely occurs during chemotherapy in patients with gastrointestinal (GI) cancer, and its clinical features remain unclear. The present study aimed to examine the clinical features of Trousseau syndrome-related cerebral infarction developed during chemotherapy for GI cancer. The present retrospective cohort study consecutively enrolled 878 patients with unresectable GI cancer who received chemotherapy at the Multidisciplinary Treatment Cancer Center, Kurume University Hospital (Kurume, Japan) between April 2014 and March 2020. Patients with colorectal cancer (n=308) were the most common, followed by those with pancreatic (n=242), gastric (n=222) and biliary tract (n=59) cancer, neuroendocrine tumors (n=34) and duodenal cancer (n=11). Among the 878 patients, Trousseau syndrome-related cerebral infarction occurred in 8 (0.9%) patients with a median age of 70.5 years (range, 58–75 years), and 50% of the patients were male (4/8). In total, 3 patients had gastric cancer, 3 had pancreatic cancer and 2 had biliary tract cancer. A greater percentage of patients with Trousseau syndrome-related cerebral infarction had hyperlipidemia (38.0%) than those without (8.2%; P=0.005). Hyperlipidemia was a risk factor for occurrence of Trousseau syndrome-related cerebral infarction with an odds ratio of 7.009 (95% confidence interval, 1.785-27.513). Trousseau syndrome-related cerebral infarction developed during GI chemotherapy was rare and hyperlipidemia may predict its onset.  相似文献   
68.
Four new clerodane-type diterpenoids, ptychonolide (1), 20-O-methylptychonal acetal (2), and an equilibrium mixture of ptychonal hemiacetal (3) and ptychonal (4), were isolated from the MeOH extract of the bark of a Brazilian plant, Ptychopetalum olacoides. The structure of 1 was elucidated as a clerodane-type diterpenoid on the basis of spectroscopic data, whereas 2 was assigned to an acetal derivative of 1. Compounds 3 and 4 existed as an equilibrium mixture. A mixture of compounds 3 and 4 was found to exhibit neurite outgrowth-promoting activities on NGF-mediated PC12 cells at concentrations ranging from 0.1 to 10.0 microM.  相似文献   
69.
AIMS: A novel blood purification material that we previously reported as a superantigen- and cytokine-adsorbing device (SCAD) was evaluated for its ability to adsorb unbound, unconjugated bilirubin (UUBil) in vitro and in vivo. METHODS: In albumin-containing buffer, UUBil was dissolved and circulated through the SCAD column. Also, bilirubin was infused into low-body weight newborn piglets and hemoperfused for 3 h over SCAD columns. RESULTS: In albumin-containing buffer, concentration of bilirubin decreased from 34 to 0.6 mg/dL within 5 h and the SCAD fiber turned brown, indicating that bilirubin was adsorbed onto the surface of the adsorbent and was not degraded during the circulation. Using the hyperbilirubinemia swine, clearances of total bilirubin (TBil), direct bilirubin (DBil), and indirect bilirubin (IdBil) were significantly higher (P<0.01) in the SCAD group compared with the control group. The clearances of TBil, DBil, and IdBil at 3 h after the initiation of the bilirubin infusion were 0.47, 0.53, and 0.45 mL/min, respectively, at a blood flow rate of 2.5 mL/min, and this result indicates that almost 20% of bilirubins were adsorbed to the SCAD column in a single passage. CONCLUSION: These results provide initial evidence that SCAD treatment is effective in the removal of UUBil and can be performed safely in newborn animals.  相似文献   
70.
Access to healthy food is a necessity for all people. However, there is still a lack of reviews on the assessment of respondent-based measures of neighborhood food environments (perceived food environments). The aim of this systematic review was to evaluate the measurement tools for perceived food environments by five dimensions of food access and to obtain the overview of their associations with dietary habits among people aged 18 years and older in middle- and high-income countries. Observational studies using perceived food environment measures were identified through a systematic review based on two databases for original studies published from 2010 to 2020. A total of 19 final studies were extracted from totally 2926 studies. Pertaining to the five dimensions of food access, 12 studies dealt with accessibility, 13 with availability, 6 with affordability, 10 with acceptability, 2 with accommodation, and 8 with a combination of two or more dimensions. Perceived healthy food environments were positively associated with healthy dietary habits in 17 studies, but 8 of them indicated statistically insignificant associations. In conclusion, this review found accessibility and availability to be major dimensions of perceived food environments. The relationship between healthy food environments and healthy diets is presumably positive and weak.  相似文献   
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