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61.
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   
62.
63.
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   
64.
Arikan S  Akcay T  Konukoglu D  Obek C  Kural AR 《Neoplasma》2005,52(4):314-317
Carcinogenesis proceeds through at least three distinct stages - initiation, promotion and progression. Free radicals play an important role in the multistep complex course of carcinogenesis. Urinary bladder has been recognized as a target organ for many carcinogens, including benzidine, beta-napthylamine, 2 napthylamine, 4-aminobiphenyl. Antioxidants have been shown to inhibit both initiation and promotion in carcinogenesis. The aim of presented study was to determine and compare the oxidant and antioxidant status in different clinical stages of bladder cancer and of control groups. Study was conducted in fifty-two (n=52) patients with transitional cell epithelial cancer of bladder and in twenty-four (n=24) healthy adults as plasma and erythrocyte controls. Malondialdehyde levels (4.636+/-1.118, 2.853+/-0.576 / 262.112+/-61.772, 203.788+/-35.340) were significantly higher and erythrocyte glutathione levels (6.272+/-1.708, 7.523+/-1.346) were significantly lower in bladder cancer patients group than in control group. Erythrocyte glutathione reductase and glutathione peroxidase (3.935+/-1.155, 5.481+/-1.626 / 8.729+/-1.614, 12.362+/-1.707) activities were significantly lower in cancer patients. In the other hand, glutathione S-transferase activities (3.100+/-1.177, 1.071+/-0.471) were found significantly increases. We suggest that the values of glutathione S-transferase enzyme activity can be used for a tumor detection approach and even as an indicator of the biological behavior of the bladder carcinoma.  相似文献   
65.
We study the role of microtubule movement in bidirectional organelle transport in Drosophila S2 cells and show that EGFP-tagged peroxisomes in cells serve as sensitive probes of motor induced, noisy cytoskeletal motions. Multiple peroxisomes move in unison over large time windows and show correlations with microtubule tip positions, indicating rapid microtubule fluctuations in the longitudinal direction. We report the first high-resolution measurement of longitudinal microtubule fluctuations performed by tracing such pairs of co-moving peroxisomes. The resulting picture shows that motor-dependent longitudinal microtubule oscillations contribute significantly to cargo movement along microtubules. Thus, contrary to the conventional view, organelle transport cannot be described solely in terms of cargo movement along stationary microtubule tracks, but instead includes a strong contribution from the movement of the tracks.  相似文献   
66.
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   
67.
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   
68.
The most represented components of clathrin-coated vesicles (CCVs) are clathrin triskelia and the adaptors clathrin assembly lymphoid myeloid leukemia protein (CALM) and the heterotetrameric complex AP2. Investigation of the dynamics of AP180-amino-terminal-homology (ANTH) recruitment during CCV formation has been hampered by CALM toxicity upon overexpression. We used knock-in gene editing to express a C-terminal–attached fluorescent version of CALM, while preserving its endogenous expression levels, and cutting-edge live-cell microscopy approaches to study CALM recruitment at forming CCVs. Our results demonstrate that CALM promotes vesicle completion upon membrane tension increase as a function of the amount of this adaptor present. Since the expression of adaptors, including CALM, differs among cells, our data support a model in which the efficiency of clathrin-mediated endocytosis is tissue specific and explain why CALM is essential during embryogenesis and red blood cell development.

Clathrin-mediated endocytosis (CME) controls multiple physiological activities in eukaryotic cells, including internalization of nutrients, receptors, and other membrane components. Endocytic clathrin-coated vesicles (CCVs) form by the recruitment of clathrin triskelia, adaptors, and other accessory proteins at specific plasma membrane sites (1). Biochemical experiments complemented by live-cell microscopy have allowed identification of several phases of CCV formation: initiation, growth/maturation, and completion (2). The initiation of “canonical” CCVs is defined by the coordinated recruitment of one triskelion and two heterotetrameric adaptor protein complexes 2 (AP2) at the plasma membrane (3). The majority of these nascent structures abort while a fraction can commit and grow further (4, 5). During the growth phase, the membrane invagination increases as more triskelia and adaptors are incorporated into the coat (6). Mass spectrometry analysis has shown that the AP2 and clathrin assembly lymphoid myeloid leukemia protein (CALM), also named Phosphatidylinositol-binding clathrin assembly protein (PICALM), are, together with clathrin, the most abundant protein components of CCVs (7, 8). While AP2 is a tetrameric adaptor (1), CALM is a single peptide chain that contains at its N terminus the AP180-amino-terminal-homology (ANTH) domain (9). The ANTH domain mediates CALM binding to phosphoinositides on the plasma membrane and to SNAREs that control the fusion of vesicles with specific acceptor membranes (10). CALM’s C terminus is unstructured and comprises binding motifs for clathrin, AP2, and EPS15 (11). Moreover, CALM is a driver of membrane curvature formation (12), which is critical for the construction of a CCV. Membrane curvature can be achieved only by overcoming local plasma membrane tension (1316) that, together with the availability of CME components (17), determines the heterogeneity of clathrin structures at the membrane surface. We hypothesized that CALM recruitment can support the formation of CCVs even under mechanically stringent conditions, such as increased membrane tension. To test this, we used quantitative live-cell microscopy to study the recruitment of CALM to forming CCVs. Since CALM overexpression has dominant negative effects on intracellular clathrin distribution and CCV formation (1820), we used gene editing to introduce protein tags at the C-terminal end of CALM so as to not perturb the N-terminal activity of CALM and to maintain its endogenous levels. Our results show that CALM functions as a major determinant of CCV formation upon membrane tension increase. Since CALM is differentially expressed among tissues, our results demonstrate that competence in CME is tissue specific and provide mechanistic explanation why CALM depletion strongly affects embryo development, red blood cell differentiation (21), and CALM polymorphisms are associated with Alzheimer''s disease (22), with minor effects in other systems.  相似文献   
69.
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   
70.
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   
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