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41.
Oral Diseases (2010) 16 , 160–166 Objective: The aim of this comparative study was to analyze cytopathologically and chemico‐physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. Materials and methods: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back‐scattered) scanning electron microscope (SEM) and X‐ray microanalysis to study piercing fragments. Results: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X‐ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. Conclusions: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted.  相似文献   
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In a previous report the effectiveness of intraperitoneal bupivacaine in reducing pain following laparoscopic cholecystectomy was demonstrated. Other methods of pain relief are commonly used but none has been compared following laparoscopic cholecystectomy. In two further studies we have compared the analgesic effect of intraperitoneal bupivacaine against wound infiltration with bupivacaine, and against intraperitoneal bupivacaine with the addition of a non-steroidal anti-inflammatory drug (NSAID) in patients undergoing laparoscopic cholecystectomy. Two consecutive studies were performed. In the first, patients in group 1 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity; patients in group 2 were given 20 ml of 0.25% bupivacaine injected into the trocar wounds. In the second study, patients in group 1 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity; patients in group 2 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity and a diclofenac suppository (100 mg) one hour before surgery. Postoperative pain was assessed with a visual analogue pain scale. There was no difference in pain scores in the two groups in either study. Intraperitoneal bupivacaine is as effective as wound infiltration. The addition of an NSAID makes no difference in the reduction of postoperative pain following laparoscopic cholecystectomy.  相似文献   
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Summary. Background: The European Network of Rare Bleeding Disorders (EN‐RBD) was established to bridge the gap between knowledge and practise in the care of patients with RBDs. Objectives: To explore the relationship between coagulation factor activity level and bleeding severity in patients with RBDs. Patients/Methods: Cross‐sectional study using data from 489 patients registered in the EN‐RBD. Coagulation factor activity levels were retrieved. Clinical bleeding episodes were classified into four categories according to severity. Results: The mean age of patients at data collection was 31 years (range, 7 months to 95 years), with an equal sex distribution. On linear regression analysis, there was a strong association between coagulation factor activity level and clinical bleeding severity for fibrinogen, factor (F) X, FXIII, and combined FV and FVIII deficiencies. A weaker association was present for FV and FVII deficiencies. There was no association between coagulation factor activity level and clinical bleeding severity for FXI. The coagulation factor activity levels that were necessary for patients to remain asymptomatic were: fibrinogen, > 100 mg dL?1; FV, 12 U dL?1; combined FV + VIII, 43 U dL?1; FVII, 25 U dL?1; FX, 56 U dL?1; FXI, 26 U dL?1; FXIII, 31 U dL?1. Moreover, coagulation factor activity levels that corresponded with Grade III bleeding were: undetectable levels for fibrinogen, FV and FXIII, < 15 U dL?1 for combined FV + VIII; < 8 U dL?1 for FVI; < 10 U dL?1 for FX; and < 25 U dL?1 for FXI. Conclusions: There is a heterogeneous association between coagulation factor activity level and clinical bleeding severity in different RBDs. A strong association is only observed in fibrinogen, FX and FXIII deficiencies.  相似文献   
46.
AIM: To identify the distribution of hepatitis B virus (HBV) subgenotype and basal core promoter (BCP) mutations among patients with HBV-associated liver disease in Indonesia.
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease.  相似文献   
47.
Migliaccio  AR; Bruno  M; Migliaccio  G 《Blood》1987,70(6):1867-1871
The biologic activity of human biosynthetic granulocyte-monocyte colony stimulating factor (GM-CSF) was investigated in serum-free culture of erythroid progenitors derived from adult peripheral blood. The morphology of erythroid bursts and the cloning efficiency of BFU-E under serum-free conditions were similar to those observed in dishes with fetal bovine serum (FBS). For these experiments, progenitor cells were partially purified by Ficoll-Paque density centrifugation, adherence to a plastic surface, and complement-mediated cytotoxicity of Leu-1+ elements. For some studies, blastlike cells were harvested directly from 6-day-old semisolid cultures. In serum-free culture of the light-density cell fraction, biosynthetic erythropoietin (Ep) was sufficient for formation of pure and mixed erythroid colonies whereas GM-CSF was required for granulocyte-monocytic colonies. When adherent and Leu-1+ cells were removed, or when in vitro differentiated blast cells were used as a source of progenitors, neither Ep or GM-CSF alone induced colony formation. In dishes supplemented with both growth factors, erythroid bursts were detected. Although the presence of GM- CSF alone did not induce formation of any colony or clusters, BFU-E were recorded when Ep was added 8 days later, suggesting that BFU-E could be maintained. Terminal maturation of the resulting erythroid bursts was delayed by 8 days. These results provide evidence that GM- CSF acts directly on early erythroid progenitors. Furthermore, they suggest that both Ep and GM-CSF are necessary to start the differentiation process.  相似文献   
48.
We have previously shown that eating disorders are a compulsive behaviour disease, characterized by frequent recall of anorexic thoughts. Evidence suggests that memory is a neocortical neuronal network, excitation of which involves the hippocampus, with recall occurring by re-excitement of the same specific network. Excitement of the hippocampus by glutamate-NMDA receptors, leading to long-term potentiation (LTP), can be blocked by ketamine. Continuous block of LTP prevents new memory formation but does not affect previous memories. Opioid antagonists prevent loss of consciousness with ketamine but do not prevent the block of LTP. We used infusions of 20 mg per hour ketamine for 10 h with 20 mg twice daily nalmefene as opioid antagonist to treat 15 patients with a long history of eating disorder, all of whom were chronic and resistant to several other forms of treatment. Nine (responders) showed prolonged remission when treated with two to nine ketamine infusions at intervals of 5 days to 3 weeks. Clinical response was associated with a significant decrease in Compulsion score: before ketamine, mean +/- SE was 44.0 +/- 2.5; after ketamine, 27.0 +/- 3.5 (t test, p = 0.0016). In six patients (non-responders) the score was: before ketamine, 42.8 +/- 3.7; after ketamine, 44.8 +/- 3.1. There was no significant response to at least five ketamine treatments, perhaps because the compulsive drive was re-established too soon after the infusion, or because the dose of opioid antagonist, nalmefene, was too low.   相似文献   
49.
Chemokine expression and leucocyte infiltration in Sjogren's syndrome   总被引:3,自引:0,他引:3  
OBJECTIVE: To investigate the expression and source of chemokines in minor salivary gland biopsies (MSGs) in patients with Sjogren's syndrome (SS). METHODS: Immunohistochemical analysis was used to determine the pattern of chemokine expression in MSGs from patients with (n=6) and without (n=5) SS, as well as to examine the phenotype of both resident and infiltrating cells expressing chemokines. RESULTS: Significant differences in the number of infiltrating mononuclear (MN) cells in patients with and without SS were noted. Ductal epithelial cells of SS biopsies expressed significantly increased levels of macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, interleukin-8 (IL-8) and RANTES (Regulated upon Activation, Normal T cell Expressed and Secreted). Biopsies from patients with SS showed that MIP-1beta was expressed by 51% of infiltrating cells, while 41% expressed MIP-1alpha, whereas 22 and 7% expressed RANTES and IL-8, respectively. CONCLUSION: Chemokines expressed by ductal epithelial cells may attract circulating leucocytes, in particular CD4+ T cells, towards the site of inflammation, thereby orchestrating the influx of MN cells characteristically seen in MSGs in SS. Chemokines may be induced directly by a putative triggering agent for SS, or secondary to the release of pro-inflammatory cytokines produced by epithelial cells. These findings further implicate epithelial cells as playing a major role in the pathogenesis of SS and implicate chemokines in the leucocyte recruitment in this setting.   相似文献   
50.
Insufficient regeneration of the adult liver is believed to cause failure to recover from severe liver disease. An undifferentiated cell population with stem-cell-like qualities known as hepatic progenitor cells (HPCs) is hypothesised to have a central role in regeneration of the adult liver during massive or chronic liver disease. Stem cells in other organ systems are believed to reside in a specialised microenvironment or niche that supports their maintenance and function. The existence of a hepatic stem cell niche might provide a means of therapeutically manipulating endogenous HPCs in vivo as a regenerative therapy.To investigate the physiological potential of HPCs to regenerate the mammalian liver, we have established a novel model of hepatocellular injury and HPC activation using genetic manipulation of hepatocytes. After hepatocyte senescence and death in this model (AhCre Mdm2flox), HPCs expand and bring about the complete regeneration of the liver parenchyma.We demonstrate that a stereotypical niche, consisting partly of macrophages, exists in both animal models and correlating human disease. Using cell tracking, we show active recruitment of extrahepatic macrophages into this niche during injury. In health, intravenous injection of macrophages results in macrophage engraftment to the liver niche, with subsequent HPC activation and changes to liver structure and function.Within the niche, macrophages use paracrine signalling to control both HPC proliferation and cell fate via TWEAK (tumour-necrosis-factor-like weak inducer of apoptosis) and the Wnt signalling pathway, respectively. After hepatocellular injury, macrophages ingest hepatocyte debris, and release Wnt which promotes HPC differentiation into hepatocytes. TWEAK is vital for HPC proliferation in the AhCre Mdm2flox model of regeneration. Here, the absence of TWEAK signalling results in liver failure and mortality.This work has demonstrated for the first time the ability of a solid organ to fully regenerate in the adult mammal from progenitor cells, and additionally highlights mechanisms by which this process can be modulated by either small molecule or cell therapy.FundingUniversity of Edinburgh.  相似文献   
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