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1.
Tumor tissue is composed of tumor cells and tumor stroma. Tumor stroma contains various immune cells and non-immune stromal cells, forming a complex tumor microenvironment which plays pivotal roles in regulating tumor growth. Recent successes in immunotherapies against tumors, including immune checkpoint inhibitors, have further raised interests in the immune microenvironment of liver carcinoma. The immune microenvironment of tumors is formed because of interactions among tumor cells, immune cells and non-immune stromal cells, including fibroblasts and endothelial cells. Different patterns of immune microenvironment are observed among different tumor subtypes, and their clinicopathological significance and intertumor/intratumor heterogeneity are being intensively studied. Here, we review the immune microenvironment of hepatocellular carcinoma, intrahepatic cholangiocarcinoma and liver metastasis of colorectal adenocarcinoma, focusing on its histopathological appearance, clinicopathological significance, and relationship with histological and molecular classifications. Understanding the comprehensive histopathological picture of a tumor immune microenvironment, in addition to molecular and genetic approaches, will further potentiate the effort for precision medicine in the era of tumor-targeting immunotherapy.  相似文献   
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Although dose reduction of S‐1 is recommended for patients with impaired renal function, dose modification for such patients has not been prospectively evaluated. The aim of the present study was to investigate the pharmacokinetic parameters of 5‐fluorouracil, 5‐chloro‐2,4 dihydroxypyridine and oteracil potassium, and to review the recommended dose modification of S‐1 in patients with renal impairment. We classified patients receiving S‐1 into 4 groups according to their renal function, as measured using the Japanese estimated glomerular filtration rate (eGFR) equation. The daily S‐1 dose was adjusted based on the patient's eGFR and body surface area. Blood samples were collected for pharmacokinetic analysis. A total of 33 patients were enrolled and classified into 4 groups as follows: 10 patients in cohort 1 (eGFR ≥ 80 mL/min/1.73 m2), 10 patients in cohort 2 (eGFR = 50‐79 mL/min/1.73 m2), 10 patients in cohort 3 (eGFR = 30‐49 mL/min/1.73 m2), and 3 patients in cohort 4 (eGFR < 30 mL/min/1.73 m2). Those in cohorts 3 and 4 treated with an adjusted dose of S‐1 showed a similar area under the curve for 5‐fluorouracil (941.9 ± 275.6 and 1043.5 ± 224.8 ng/mL, respectively) compared with cohort 2 (1034.9 ± 414.3 ng/mL). Notably, while there was a statistically significant difference between cohort 1 (689.6 ± 208.8 ng/mL) and 2 (= 0.0474) treated with an equal dose of S‐1, there was no significant difference observed in the toxicity profiles of the cohorts. In conclusion, dose adjustment of S‐1 in patients with impaired renal function using eGFR is appropriate and safe.  相似文献   
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Early onset periodontitis is rarely seen in infants, though often leads to an acute and serious clinical course when encountered in such patients. Autoimmune neutropenia presents systemic and dental symptoms, as depressed resistance to bacterial infection is caused by a disorder that reduces the number of neutrophils. This disease can result in not only gingival inflammation but also destruction of periodontal tissues, such as attachment loss, alveolar bone absorption, and early tooth loss in primary as well as mixed dentition. Here, we report treatment of a child with marginal periodontitis from the age of 3 years–7 years 9 months. No systemic manifestations were noted until 3 years of age, thus the patient had never received a detailed examination or medication related to the disease. Following examinations at our department, we referred the patient to a pediatrician at our university hospital for possible systemic disease, who made a diagnosis of autoimmune neutropenia. Although administration of antibiotics and professional dental care were continued, neutrophil count was not increased and progressive periodontal destruction was observed. Extraction of teeth with poor prognosis was performed and a prosthetic strategy for the missing teeth developed. It is important to recognize that periodontitis along with autoimmune neutropenia can appear in infants, even though the incidence is quite low. Early detection and early treatment of this disease is necessary for delaying progression of periodontitis and optimal occlusal induction of permanent teeth.  相似文献   
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OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children.  相似文献   
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We examined the mechanisms of the inhibition of DNA synthesis by a new platinum compound, (-)-( R )-2-aminomethylpyrrolidine(1,1-cyclobutane-dicarboxylato)-2-platinum(II) monohydrate (DWA-2114R), a derivative of the antitumor drug cis- diamminedichloroplatinum(II) (CDDP), using prokaryotic and eukaryotic DNA polymerases. Preincubating activated DNA with CDDP or DWA-2114R reduced its template activity for prokaryotic and eukaryotic DNA polymerases in a dose-dependent manner. DWA2114R required six times greater drug concentration and two times longer incubation time to show the same decrease of the template activity compared to CDDP. Treatment of primed pUC118 ssDNA templates with the two drugs followed by second-strand synthesis by prokaryotic and eukaryotic DNA polymerases revealed that DWA2114R bound to DNA in a similar manner to CDDP and these adducts blocked DNA elongation by DNA polymerases of eukaryotes as well as of prokaryotes. With these two drugs, the elongations by E. coli DNA polymerase I (Klenow fragment), T7 DNA polymerase and calf thymus DNA polymerase α were strongly arrested at guanine-guanine sequences (GG). Stop bands were also observed at adenine-guanine sequences (AG) guanine-adenine-guanine sequences (GAG) and mono-guanine sequence (G). Calf testis DNA polymerase β was also arrested efficiently at AG, GAG and G, but much more weakly at GG. This pattern was common to DWA2114R and CDDP.  相似文献   
10.
Although aortic valve replacement (AVR) is an effective treatment for patients with aortic valvular disease, the implantation of a small aortic prosthesis may result in residual left ventricular outflow stenosis and transvalvular gradient. In this study, the outcome in the long-term period of patients treated with a small aortic prosthesis was analyzed retrospectively. Twenty-four patients with AVR were divided into two groups, group A and group B. Group A consisted of 16 patients with 21 mm-sized prosthetic valves, and group B consisted of 8 patients with 19 or 16 mm-sized prosthetic valves. There were no significant differences in preoperative cardiac function or operative procedure in the two groups. The mean follow-up period (months) was 55.0 in group A and 51.3 in group B. RESULTS: One patient died of cerebral infarction in group A. There were no significant differences in cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and left ventricular mass index (LVMI) between the two groups. Postoperative physical activity according to the New York Heart Association (NYHA) classification showed no significant differences in the two groups. Despite using a small prostheses for AVR, the postoperative course was good in the long-term period, although careful follow-up is necessary.  相似文献   
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