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41.
We herein report a 36-year-old man with repeated necrotizing lymphadenitis due to MEFV gene mutations. The patient''s chief complaints were a fever and painful cervical lymphadenopathy. We diagnosed him with necrotizing lymphadenitis based on the pathological findings of the lymph nodes and the exclusion of other differential diseases. The same episode recurred four times. We speculated the involvement of autoinflammatory backgrounds and detected MEFV gene mutations of E148Q (homo), P369S, and R408Q. Considering the elevation of interleukin-18, these mutations probably played roles in the repeated necrotizing lymphadenitis.  相似文献   
42.
43.
Although the use of high-level Er:YAG laser irradiation has been increasing in periodontal and peri-implant therapy, the effects of low-level Er:YAG laser on surrounding tissues and cells remain unclear. In the present study, the effects of low-level Er:YAG laser irradiation on osteoblast proliferation were investigated. Cells of the osteoblastic cell line MC3T3-E1 were treated with low-level Er:YAG laser irradiation with various combinations of laser settings (fluence 0.7–17.2 J/cm2) and in the absence or presence of culture medium during irradiation. On day 1 and/or day 3, cell proliferation and death were determined by cell counting and by measurement of lactate dehydrogenase (LDH) levels. Further, the role of mitogen-activated protein kinase (MAPK) pathways in laser-enhanced cell proliferation was investigated by inhibiting the MAPK pathways and then measuring MAPK phosphorylation by Western blotting. Higher proliferation rates were found with various combinations of irradiation parameters on days 1 and 3. Significantly higher proliferation was also observed in laser-irradiated MC3T3-E1 cells at a fluence of approximately 1.0–15.1 J/cm2, whereas no increase in LDH activity was observed. Further, low-level Er:YAG irradiation induced the phosphorylation of extracellular signal-regulated protein kinase (MAPK/ERK) 5 to 30 min after irradiation. Although MAPK/ERK 1/2 inhibitor U0126 significantly inhibited laser-enhanced cell proliferation, activation of stress-activated protein kinases/Jun N-terminal kinase (SAPK/JNK) and p38 MAPK was not clearly detected. These results suggest that low-level Er:YAG laser irradiation increases osteoblast proliferation mainly by activation of MAPK/ERK, suggesting that the Er:YAG laser may be able to promote bone healing following periodontal and peri-implant therapy.  相似文献   
44.
BACKGROUND AND OBJECTIVES: This study compared the surface morphology as well as the biocompatibility of dental root cementum treated with Er:YAG laser irradiation alone and with the laser irradiation followed by chemical and/or mechanical conditioning. STUDY DESIGN/MATERIALS AND METHODS: Healthy cementum plates were randomly assigned to the following control and treatment groups: (1) untreated control (C), (2) Er:YAG laser irradiation (L), (3) laser plus tetracycline HCl (TC) placement (L+TP), (4) laser plus TC burnishing (L+TB), (5) laser plus EDTA gel placement (L+EP), (6) laser plus EDTA gel burnishing (L+EB), (7) laser plus saline solution burnishing (L+SB), and (8) laser plus minocycline-HCl paste placement (L+MP). Specimens were subjected to scanning electron microscopy (SEM), histological observation and attachment assay using periodontal ligament (PDL) fibroblasts. RESULTS: The laser irradiation produced a thin affected layer (5.7 microm thickness) with a superficial microstructure on the cementum surface. The characteristic microstructures of the lased surface were fragile and could be removed by chemical and/or mechanical conditioning treatments. The L+TB group exhibited marked exposure of collagen fibers after removal of the microstructures on the lased surface. The L+EP group presented a peculiar, smooth surface without exposure of collagen fibers and a uniform arrangement of spherical microparticles on the ultra-high magnification of SEM. In cell attachment assay, the L+TB group exhibited the greatest number of attached cells among all the groups, followed by the L+EP, L+SB and control group. The laser alone group exhibited the lowest number of cells. CONCLUSIONS: The characteristic microstructure of the root cementum surface after Er:YAG laser irradiation has a tendency to hinder the early attachment of PDL cells. However, chemical and/or mechanical root conditioning treatment may improve and increase the biocompatibility of the Er:YAG laser-treated root cementum by removing the microstructures of the surface and/or further exposing the collagen fibers.  相似文献   
45.
A 45-year-old female was presented with progressive dyspnea and bilateral leg edema. Pulmonary angiography revealed total occlusion of the right pulmonary artery and significant stenosis of the left pulmonary artery. The inferior lobar artery as well as the segmental arteries were well patent. No pathology was detected elsewhere at the aorta and its branches. The diagnosis of chronic pulmonary arterial occlusion by isolated Takayasu arteritis was made because of the characteristic pattern of angiographic findings and the presence of unusual shunt formation from the coronary artery to the peripheral portion of the pulmonary artery, as well as a characteristic presentation of HLA typing in blood analysis, which strongly suggested the diagnosis of Takayasu arteritis. To restore the pulmonary blood flow, we employed reconstructive surgery by means of bypass procedure, using PTFE graft. Postoperatively there was marked improvement in cardiopulmonary function and the quality of life of the patient. The graft was proved to be patent at long-term follow-up study. An extremely rare case of chronic occlusive pulmonary arteritis, which was surgically treated by means of bypass procedure, is reported herein, and a brief review of previous reports on this subject was attempted.  相似文献   
46.
Marked hypophosphatemia is common after major hepatic resection, but the pathophysiologic mechanism remains unknown. We used a partial hepatectomy (PH) rat model to investigate the molecular basis of hypophosphatemia. PH rats exhibited hypophosphatemia and hyperphosphaturia. In renal and intestinal brush-border membrane vesicles isolated from PH rats, Na+-dependent phosphate (Pi) uptake decreased by 50%–60%. PH rats also exhibited significantly decreased levels of renal and intestinal Na+-dependent Pi transporter proteins (NaPi-IIa [NaPi-4], NaPi-IIb, and NaPi-IIc). Parathyroid hormone was elevated at 6 hours after PH. Hyperphosphaturia persisted, however, even after thyroparathyroidectomy in PH rats. Moreover, DNA microarray data revealed elevated levels of nicotinamide phosphoribosyltransferase (Nampt) mRNA in the kidney after PH, and Nampt protein levels and total NAD concentration increased significantly in the proximal tubules. PH rats also exhibited markedly increased levels of the Nampt substrate, urinary nicotinamide (NAM), and NAM catabolites. In vitro analyses using opossum kidney cells revealed that NAM alone did not affect endogenous NaPi-4 levels. However, in cells overexpressing Nampt, the addition of NAM led to a marked decrease in cell surface expression of NaPi-4 that was blocked by treatment with FK866, a specific Nampt inhibitor. Furthermore, FK866-treated mice showed elevated renal Pi reabsorption and hypophosphaturia. These findings indicate that hepatectomy-induced hypophosphatemia is due to abnormal NAM metabolism, including Nampt activation in renal proximal tubular cells.Inorganic phosphate (Pi) absorption in the renal proximal tubules and small intestine is important for Pi homeostasis.1 The Na+-dependent Pi (Na/Pi) transport system includes type IIa and type IIc Na/Pi transporters, which are localized in the apical membrane of the proximal tubular cells, and type IIb Na/Pi transporters, which are localized in the apical membrane of the intestinal epithelial cells.1,2 Pi (re)absorption is regulated by the dietary Pi content, parathyroid hormone (PTH), and the active metabolite of vitamin D, 1α, 25-dihydroxyvitamin D3 [1,25(OH)2D3].3 Other phosphaturic hormones, termed phosphatonins, also control renal Pi handling.4 The discovery that fibroblast growth factor (FGF) 23, the first identified phosphatonin,5 originated from osteocytes established the concept of the bone-kidney axis.6,7The incidence of liver transplantation has steadily increased and the incidence of partial hepatectomy (PH) has also consequently increased.8 Hypophosphatemia frequently occurs after liver resection.911 Acute hypophosphatemia causes septicemia and is associated with a poor prognosis.11,12 Acute hypophosphatemia is of considerable clinical relevance because many hepatectomized patients develop marked hypophosphatemia and, thus, large doses of Pi replacement are required to maintain metabolic homeostasis.13 Urinary Pi excretion is markedly increased in many patients. After hepatectomy, hypophosphatemia is associated with hyperphosphaturia.13For many years, the increased metabolic demand of the regenerating liver was considered the underlying pathologic mechanism of hypophosphatemia. The magnitude of Pi uptake by the recovering liver, however, cannot explain the severity of the resulting hypophosphatemia.11 Hepatectomy-induced hypophosphatemia is associated with an increased renal fractional excretion index for Pi unrelated to intact FGF23, FGF7, or secreted frizzled-related protein 4 as a phosphaturic factor,14 indicating that other factors have a role in the pathogenesis of hypophosphatemia.Nicotinamide (NAM) inhibits intestinal and renal Na/Pi transport activity in normal rats.1517 Administration of NAM to rats produces a specific dose-dependent inhibition of Na/Pi transport across the renal brush-border membrane (BBM) and an increase in urinary Pi excretion.16,17 NAM suppresses hyperphosphatemia in hemodialysis patients.18 Nicotinamide phosphoribosyltransferase (Nampt) catalyzes the first rate-limiting step in converting NAM to NAD,19,20 which is essential for cellular metabolism, energy production, and DNA repair.2022 Nampt exists in two known forms: intracellular Nampt (iNampt) and secreted extracellular Nampt (eNampt).23 eNampt also generates an intermediate product, nicotinamide mononucleotide (NMN).23Our findings indicate that the acceleration of NAM metabolism through Nampt function in the kidney is involved in the hepatectomy-induced hypophosphatemia in rodent models. This study also suggests that NAM metabolism through the liver-kidney axis is important in Pi homeostasis.  相似文献   
47.
H. Soda    K. Kuriyama    M. Tomonaga    E. Yao    T. Amenomori    Y. Yoshida    T. Matsuo    I. Jinnai    N. Sadamori  M. Ichimaru 《British journal of haematology》1985,59(4):671-679
A case of Philadelphia (Ph1) chromosome negative chronic myeloid leukaemia (CML) developed lymphoid crisis. Immunological marker studies disclosed that the lymphoid cells were sheep erythrocyte-rosetting-, Leu-1+, Leu-5+, OKT-4+, OKT-8+, common ALL antigen-, HLA-DR-, cytoplasmic and surface immunoglobulin-, MAS 036C(antithymocyte)+ (after in vitro culture) and terminal deoxynucleotidyl transferase-, indicating T-cell phenotypes, probably of common thymocytes. Cytochemical staining also demonstrated immature T-cell characters: dot-positivity for acid phosphatase and beta-glucuronidase, and negative for acid alpha-naphthyl acetate esterase. All bone marrow metaphases exhibited normal karyotypes. Our observation suggests that the neoplastic features of a common stem cell for myeloid and lymphoid cell lines are very similar in Ph1 positive and negative CMLs, and that the stem cell can differentiate towards T-lineage.  相似文献   
48.

Purpose

Elderly patients with multiple infarctions revealed a high prevalence of postoperative stroke after coronary artery bypass grafting (CABG). However, postoperative neurological complications and characteristics of silent brain infarction (SBI) have not been evaluated in elderly patients undergoing CABG.

Methods

Four hundred forty-nine patients (??60 years old) scheduled for CABG underwent cerebral magnetic resonance imaging (MRI) and MR angiography preoperatively to assess cerebral infarctions and carotid and intracranial artery stenosis. Atherosclerosis of the ascending aorta was assessed by epiaortic ultrasound during surgery. Patients were sorted by their history of cerebrovascular disease (CVD) and the presence of infarction by MRI: SBI (infarction without CVD), BI (symptomatic brain infarction; CVD and infarction), and controls (no findings of either CVD or infarction).

Results

SBI was found in 35.5% of the 449 patients and increased with age. The prevalence of pre-existing multiple infarctions was less frequent in SBI than in BI. The incidence of postoperative stroke and cognitive dysfunction was 1.3% and 4.9% in controls (n?=?225), 5.7% and 15.2% in SBI (n?=?158), and 9.1% and 18.2% in BI (n?=?66). Patients with SBI were older and had more renal dysfunction and preoperative cognitive impairment. Stepwise logistic regression demonstrated that age, renal dysfunction, preoperative cognitive impairment, atherosclerosis of the ascending aorta, and intracranial arterial stenosis were associated significantly with SBI.

Conclusion

Patients with SBI were ranked at moderate risk of neurological complications after CABG between control and BI. Increased age, renal dysfunction, and preoperative cognitive impairment appeared to be strongly associated with SBI.  相似文献   
49.
We report a case of adrenal pheochromocytoma in a patient with neurofibromatosis type 1 (NF1). A 65-year-old female patient was admitted to our hospital for examination of a right adrenal mass. The adrenal tumor was incidentally discovered by abdominal computed tomography during examination for hypertension in another hospital. She had large multiple neurofibromatous lesions and café-au-lait spots on the trunk. We thought that it was difficult to make a skin incision on normal skin. Serum and urinary catecholamines were markedly increased. Magnetic resonance imaging revealed a solid round tumor 3 cm in diameter, located in the right adrenal gland. Laparoscopic right adrenalectomy was performed. Serum and urinary catecholamines returned to the normal range on post-operative day 10. Laparoscopic surgery may be a good option for NF1 patients with pheochromocytoma, especially those who had multiple neurofibromatosis on the trunk.  相似文献   
50.

Background

The aim of this study was to evaluate how sacrifice of the portal vein and/or hepatic vein affects remnant liver dysfunction after lateral segmentectomy or left lobe hepatectomy.

Materials and methods

Among 130 patients who underwent donor hepatectomy between March 2002 and July 2011, we enrolled lateral segment (n = 15) and left lobe donors (n = 40). We evaluated the postoperative courses and the territory of venous obstruction or congestion based on the sacrificed portal vein or hepatic vein after the donor operation: lateral segment grafts (P4a, P4b, LV4) and left lobe grafts (MV5, MV8) according to the results analyzed by MeVis Distant Service.

Results

Among lateral segment donors, the predicted sacrificed territory of portal vein and hepatic vein was 14.3% (7.3%-19.4%) in P4a + 4b: (P4a: 8.6%, P4b: 5.8%) and 2.9% (0%-8.4%) in LV4, respectively. On the other hand, in left lobe donors, the predicted congestive territory of the hepatic vein was 17.6% (2.8%-33.0%) in MV5 + 8 (7.8% in MV5 and 9.8% in MV8, respectively). The incidence of patients whose postoperative peak aspartate aminotransferase (AST) or alanine aminotransferase levels were higher than 500 IU/L was 20% in the lateral segment donors and 5% in the left lobe donors. The peak postoperative AST levels and territory of MV5 + 8 showed a significant positive correlation (R = 0.569, P < .05) among left lobe donors.

Conclusion

Territories of P4 in lateral segment donors and MV5 + 8 in left lobe donors impacted postoperative liver dysfunction. It is important to recognize the precise territory of the portal vein and the hepatic vein before the donor operation.  相似文献   
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