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101.
Gastrointestinal stromal tumors (GISTs) have been reported to occasionally occur in patients with neurofibromatosis type 1 (NF-1), and many cases have had multiple lesions predominantly involving the small intestine. We report herein a case of multiple GISTs associated with NF-1 from whom laparoscopic surgery was beneficial. In a 79-year-old female admitted with anemia and melena, the abdominal computed tomography revealed a tumor arising from the small intestine. Laparoscopic surgery was performed, and another small tumor was revealed during laparoscopic observation. Extracorporeal partial and wedge resection of the small intestine were undertaken. Both lesions were diagnosed as typical GISTs of low risk. Laparoscopic surgery would be useful for examination and a minimally invasive approach to tumors of the small intestine, especially on cases with the possibility of multiple tumors.  相似文献   
102.
It is suggested that masticatory dysfunction affects the central nervous system; however, the underlying mechanism remains unknown. Brain‐derived neurotrophic factor (BDNF) and its receptor, TrkB, are known to play important roles in memory and learning. In this study, we examined the effects of mastication on memory, the expression levels of BDNF and TrkB, and the number of neurons in the hippocampus of mice. Male C57 BL/6J mice (3 weeks old) were randomly divided into the control group (N = 7) fed chow pellets and the experimental group (N = 7) fed a liquid diet, which reduces mastication during eating. At 14 weeks of age, we performed a passive avoidance test and found that memory and learning ability were impaired in the experimental group compared with the control group. After the behavioral experiment, brains were harvested and analyzed morphologically and biochemically. In the hippocampus of the experimental group, the expression levels of BDNF were significantly higher, whereas those of TrkB were lower than those of the control group. In the cerebral cortex, these levels remained unchanged between the two groups. The ratio of phospho‐p44/42 ERK/pan ERK, a downstream molecule of BDNF/TrkB signaling, in the experimental group was significantly lower than that of the control group in the cortex and hippocampus. The number of pyramidal neurons in the hippocampus was lower in the experimental group than in the control group. These findings suggest that reduced mastication induced by a liquid diet in early childhood may impair memory and learning ability, accompanied by neuronal loss in the hippocampus. © 2014 Wiley Periodicals, Inc.  相似文献   
103.
The aim of this study was to investigate corticobasal syndrome with respect to underlying pathologies, the ability of current clinical criteria to detect early stages of disease, and symptoms and signs predicting background pathologies. We retrospectively analyzed the clinicopathological findings from patients with corticobasal syndrome. We also analyzed whether those findings fulfilled the diagnostic criteria for corticobasal degeneration (CBD). Finally, we investigated characteristic clinical features that are specific to each background pathology. Of 10 consecutive autopsied patients who had corticobasal syndrome (mean age ± standard deviation, 67.9 ± 9.3 years; male:female ratio, 6:4), three had corticobasal degeneration pathology, three had progressive supranuclear palsy, three had Alzheimer's disease, and one had atypical four‐repeat tauopathy. Nine patients fulfilled Mayo criteria, and all 10 patients fulfilled modified Cambridge criteria at the later stage, but only two patients fulfilled either clinical criteria within 2 years of disease onset. Five patients fulfilled the clinical criteria for possible CBD (p‐CBD), and one patient fulfilled the clinical research criteria for probable sporadic CBD (cr‐CBD) at the later stage. Only two patients fulfilled the criteria for either p‐CBD or cr‐CBD within 2 years of disease onset. Although we could not find any predictive characteristic clinical features that were specific to CBD pathology, only patients with progressive supranuclear palsy developed apraxia of eyelid opening and cerebellar ataxia. Myoclonus and memory impairment, especially if they appear at an early stage of the disease, may predict Alzheimer's disease pathology. Sensitivity of the available clinical criteria for corticobasal syndrome was poor within 2 years of disease onset. © 2013 International Parkinson and Movement Disorder Society  相似文献   
104.
Vascular calcification (VC) is a life-threatening complication of CKD. Severe protein restriction causes a shortage of essential amino acids, and exacerbates VC in rats. Therefore, we investigated the effects of dietary l-lysine, the first-limiting amino acid of cereal grains, on VC. Male Sprague-Dawley rats at age 13 weeks were divided randomly into four groups: low-protein (LP) diet (group LP), LP diet+adenine (group Ade), LP diet+adenine+glycine (group Gly) as a control amino acid group, and LP diet+adenine+l-lysine·HCl (group Lys). At age 18 weeks, group LP had no VC, whereas groups Ade and Gly had comparable levels of severe VC. l-Lysine supplementation almost completely ameliorated VC. Physical parameters and serum creatinine, urea nitrogen, and phosphate did not differ among groups Ade, Gly, and Lys. Notably, serum calcium in group Lys was slightly but significantly higher than in groups Ade and Gly. Dietary l-lysine strongly suppressed plasma intact parathyroid hormone in adenine rats and supported a proper bone-vascular axis. The conserved orientation of the femoral apatite in group Lys also evidenced the bone-protective effects of l-lysine. Dietary l-lysine elevated plasma alanine, proline, arginine, and homoarginine but not lysine. Analyses in vitro demonstrated that alanine and proline inhibit apoptosis of cultured vascular smooth muscle cells, and that arginine and homoarginine attenuate mineral precipitations in a supersaturated calcium/phosphate solution. In conclusion, dietary supplementation of l-lysine ameliorated VC by modifying key pathways that exacerbate VC.Medial vascular calcification is common in aging, diabetes, and CKD.14 Because the presence of vascular calcification is strongly associated with increased cardiovascular morbidity and mortality, several studies in both animals and humans have sought ways to reduce the extent of vascular calcification.510 However, satisfactory therapies have not yet been established.11Adenine-induced renal failure is one of the commonly used animal models for studying the development of vascular calcification, but the prevalence of vascular calcification in this model is not very high. Indeed, Price et al. reported that vascular calcification was detected in only 30% of rats with adenine-induced chronic renal failure (adenine rats) fed a normal-protein diet.5 These authors speculated that consistent vascular calcification might require a longer period of adenine feeding. On the basis of this idea, they designed a low-protein (LP) diet in an attempt to reduce the nitrogen load and thus enable the rats to thrive on the adenine diet for longer periods. As a result of this attempt, Price et al. unexpectedly found that adenine rats fed a LP diet had extensive vascular calcification without a longer feeding period.5 All 13 adenine rats fed the LP diet had uniform alizarin red staining of the aorta, whereas only 3 of the 11 adenine rats fed a normal-protein diet had partial calcification.5 These findings indicated that dietary protein deficiency correlates with the extent of vascular calcification.Proteins are usually made from 20 kinds of amino acids. On the basis of nutritional requirements, these amino acids can be divided into two groups: essential amino acids (EAAs) and non-EAAs. Because restriction of dietary protein results in a shortage of EAAs, the level of dietary EAAs may be relevant to the extent of vascular calcification. Among nine EAAs, this study focused on l-lysine (l-Lys) based on the following three reasons. First, l-Lys is the first-limiting amino acid in most cereal grains.12 Second, the safety of l-Lys supplementation has been verified in the area of animal husbandry. l-Lys has long been added to feed grains in order to improve the utility of feed proteins.13 Third, several studies have demonstrated that dietary supplementation with l-Lys protects bones from osteoporosis, a pathologic condition that often coexists with vascular calcification.14,15 These points prompted us to hypothesize that supplementation with l-Lys would ameliorate vascular calcification. Therefore, in this study, we tested this hypothesis using adenine rats.  相似文献   
105.
106.
Although stapler dissection and closure is commonly used for laparoscopic distal pancreatectomy (LDP), it is risky in patients with thick pancreatic parenchyma or titanium allergy. We performed laparoscopic pancreatic parenchymal dissection with cavitron ultrasonic surgical aspirator (CUSA) successfully in a patient with titanium allergy. Slinging the pancreas with nylon tape delineates the surgical plane. Pancreatic parenchyma was transected by CUSA in an almost bloodless field. Pancreatic duct branches and vessels were adequately exposed and dissected with a vessel sealing system. The main pancreatic duct was closed with Hem-O-lock. CUSA is an alternative to stapler dissection during LDP in select patients.  相似文献   
107.
OBJECTIVE: To examine in vivo the effects of a mixture of high molecular weight hyaluronic acid (HA) plus phospholipids on joint lubrication and articular cartilage degeneration. METHODS: Experimental osteoarthritis (OA) of the right knee was induced by anterior cruciate and medial collateral ligament transection in 40 rabbits. The animals were subjected to 8 consecutive weekly intraarticular administrations of high molecular weight HA (the HA200 group), conventional molecular weight HA (the HA80 group), or high molecular weight HA plus L-delta dipalmitoyl phosphatidylcholine liposomes (the PHA group) and were killed 1 week after the final injection. The remaining transected right knees (the OA group) and randomly selected nontransected contralateral left knees (the control group) were collected simultaneously. Each group (n = 10) was divided into 2 equal subgroups, one of which was evaluated histologically while the other was subjected to a lubricating ability test using a pendulum friction tester. RESULTS: The injected knees had a tendency to demonstrate less damage to the articular cartilage compared with the OA group, and the histologic findings in all groups except for the PHA group differed significantly from the control group. There was a significant difference in the mean +/- SD friction coefficient between the control group (0.0100 +/- 0.00300) and the OA (0.0206 +/- 0.00649), HA200 (0.0190 +/- 0.00427), and HA80 (0.0177 +/- 0.00712) groups (P < 0.05 for each comparison), but not between the control group and the PHA group (0.0150 +/- 0.00330) (P = 0.15). CONCLUSION: To our knowledge, this is the first in vivo study to examine whether intraarticular injections of phospholipids influence joint lubrication by acting as a boundary lubricant, thus protecting articular cartilage from degenerative changes.  相似文献   
108.
Primary sclerosing cholangitis (PSC) frequently accompanies inflammatory bowel diseases. In an attempt to increase our understanding of the pathogenesis of PSC, we studied bile duct changes in rats with colitis which had been givenn-formyll-methioninel-leucinel-tyrosine (fMLT) rectally; fMLT is one of the chemotactic peptides produced byEscherichia coli, and is secreted into the bile by hepatocytes after it enters the portal blood. Transrectal administration of fMLT induced a marked inflammation in the portal triad and mild hepatocyte necrosis on the 4th day. The infiltrating leukocytes in the portal tract were mostly mononuclear cells, which densely infiltrated around the bile ducts. These mononuclear cells appeared to attach to bile duct epithelial cells, and they were more numerous in the smaller bile ducts. Electron microscopy revealed that lymphocytes were in direct contact with bile duct lining cells and that some epithelial cells had degenerated or collapsed. These results suggest that thisE. coli-derived peptide may induce cholangitis in the small bile duct through cell-mediated mechanisms. Since these pathologic changes resemble those of the bile duct observed in the early stage of PSC, it can be concluded that bacterial chemotactic peptides may play a role in the pathogenesis of small-duct PSC.  相似文献   
109.

Background

IgG4 production is regulated by type 2 (IL-4 and IL-13) and regulatory (IL-10) cytokines involved in the pathophysiology of chronic rhinosinusitis (CRS). We sought to determine the pathophysiological characteristics of IgG4-positive cells in sinonasal tissues in CRS, especially eosinophilic CRS (ECRS).

Methods

IgG4-positive cells in uncinate tissues (UT) and nasal polyps (NP) were examined by immunohistochemistry. Associations between the number of IgG4-positive cells and clinicopathological factors were analyzed. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of IgG4-positive cells in tissue that can predict the post-operative course.

Results

IgG4 was mainly expressed in infiltrating plasma and plasmacytoid cells, and the number of IgG4-positive cells was significantly higher in NP, especially those from severe ECRS patients, than in UT. In CRS patients, the number of IgG4-positive cells significantly and positively correlated with blood and tissue eosinophilia, radiological severity, and serum level of total IgE. The number of infiltrating IgG4-positive cells was significantly higher in patients with a poor post-operative course (sustained sinus shadow 6 months after surgery) than in those with a good one. The number of IgG4-positive cells in NP could discriminate patients with a good or a poor post-operative course (area under the curve: 0.769). Also, 73.3% sensitivity and 82.5% specificity were achieved when the cut-off value was set at 17 cells/high-power field.

Conclusions

Our results suggest that the local expression of IgG4 on cells may be used as a biomarker that reflects the pathophysiology of CRS, including the post-operative course.  相似文献   
110.

Background

IL-10 is a major anti-inflammatory cytokine that prevents inflammation-mediated tissue damage. We characterized the production of IL-10 by sinonasal tissue cells following exposure to Staphylococcus aureus enterotoxin B (SEB), which elicits cellular responses and is associated with the pathogenesis of eosinophilic chronic rhinosinusitis (ECRS).

Methods

Dispersed nasal polyp (NP) cells and uncinate tissue (UT) cells were prepared from patients with CRS with and without NP, respectively. Cells were incubated with SEB, and then the levels of IL-10 in the cell supernatants were determined. The effect of neutralizing IL-10 on SEB-induced IL-5, IL-13, IFN-γ, and IL-17A production was examined. Expression of IL-10 in NPs was also determined.

Results

IL-10 was expressed in infiltrating inflammatory cells in NPs. NP cells, especially non-adherent NP cells, produced substantial amounts of IL-10 in response to SEB. Although baseline production of IL-10 was significantly higher in NP cells than UT cells, the degree of IL-10 response to SEB was not significantly different between the cell types. The degree of IL-10 production was negatively correlated with the degree of eosinophilia both in tissues and peripheral blood whereas positively correlated with the 1-s forced expiratory volume/forced vital capacity ratio. Patients with severe ECRS displayed a significant decrease in IL-10 production compared with those with non-ECRS. IL-10 neutralization significantly augmented SEB-induced IL-13 and IFN-γ production by NP cells.

Conclusions

Impaired IL-10 production in response to SEB in NP may exacerbate the pathophysiology of ECRS including eosinophilia and lower airway obstruction.  相似文献   
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