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81.
Accumulated Clonal Genetic Alterations in Familial and Sporadic Colorectal Carcinomas with Widespread Instability in Microsatellite Sequences 总被引:16,自引:3,他引:16
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82.
David R. Burk Patti Senechal-Willis Linda C. Lopez Brenda G. Hogue Sasha M. Daskalova 《Journal of ethnopharmacology》2009
Ethnopharmacological relevance
The wild basil Clinopodium vulgare L. is commonly used in Bulgarian folk medicine for treatment of irritated skin, mastitis- and prostatitis-related swelling, as well as for some disorders accompanied with significant degree of inflammation (e.g. gastric ulcers, diabetes, and cancer).Aim of study
To determine the effect of aqueous extract of Clinopodium vulgare L. on LPS-induced inflammatory responses of murine RAW 264.7 macrophages.Materials and methods
Cell cytotoxicity was evaluated by MTT assay. Protein expression levels were monitored by Western blot analysis. Production of NO and PGE2 was measured by the Griess colorimetric method and enzyme immunoassay, respectively. Activation of MMP-9 was visualized by gelatin zymography. Cytokine levels were determined by BioPlex assay. Intracellular ROS and free radical scavenging potential were measured by DCFH-DA and DPPH method, respectively. Xanthine oxidase activity was evaluated spectrophotometrically.Results
The extract suppresses NF-κB activation by preventing Iκ-B phosphorylation and inhibits the phosphorylation of p38 and SAPK/JNK MAPKs. It down-regulates iNOS expression which manifests as a drastic decrease of NO production, inhibits MMP-9 activation, but does not affect COX-2 protein levels and reduces only slightly the released PGE2. Secretion of IL-1β and Il-10 is greatly reduced, whereas suppression of TNF-α and GM-CSF production is less dramatic. The extract has strong free radical scavenging properties and exerts inhibitory effect on xanthine oxidase activity, which lowers the levels of intracellular ROS.Conclusion
The study provides evidence for the anti-inflammatory potential of Clinopodium vulgare L. aqueous extract. 相似文献83.
A. Greinacher K. Selleng T. E. Warkentin 《Journal of thrombosis and haemostasis》2017,15(11):2099-2114
Summary
Autoimmune heparin‐induced thrombocytopenia (aHIT) indicates the presence in patients of anti‐platelet factor 4 (PF4)–polyanion antibodies that are able to activate platelets strongly even in the absence of heparin (heparin‐independent platelet activation). Nevertheless, as seen with serum obtained from patients with otherwise typical heparin‐induced thrombocytopenia (HIT), serum‐induced platelet activation is inhibited at high heparin concentrations (10–100 IU mL?1 heparin). Furthermore, upon serial dilution, aHIT serum will usually show heparin‐dependent platelet activation. Clinical syndromes associated with aHIT include: delayed‐onset HIT, persisting HIT, spontaneous HIT syndrome, fondaparinux‐associated HIT, heparin ‘flush’‐induced HIT, and severe HIT (platelet count of < 20 × 109 L?1) with associated disseminated intravascular coagulation (DIC). Recent studies have implicated anti‐PF4 antibodies that are able to bridge two PF4 tetramers even in the absence of heparin, probably facilitated by non‐heparin platelet‐associated polyanions (chondroitin sulfate and polyphosphates); nascent PF4–aHIT‐IgG complexes recruit additional heparin‐dependent HIT antibodies, leading to the formation of large multimolecular immune complexes and marked platelet activation. aHIT can persist for several weeks, and serial fibrin, D‐dimer, and fibrinogen levels, rather than the platelet count, may be helpful for monitoring treatment response. Although standard anticoagulant therapy for HIT ought to be effective, published experience indicates frequent failure of activated partial thromboplastin time (APTT)‐adjusted anticoagulants (argatroban, bivalirudin), probably because of underdosing in the setting of HIT‐associated DIC, known as ‘APTT confounding’. Thus, non‐APTT‐adjusted therapies with drugs such as danaparoid and fondaparinux, or even direct oral anticoagulants, such as rivaroxaban or apixaban, are suggested therapies, especially for long‐term management of persisting HIT. In addition, emerging data indicate that high‐dose intravenous immunoglobulin can interrupt HIT antibody‐induced platelet activation, leading to rapid platelet count recovery.84.
Thanks to the advent of laparoscopic techniques, the last decade and a half have witnessed a radical change in the treatment
of esophageal achalasia. Because of the high success rate of the laparoscopic Heller myotomy, surgery has now become in many
centers the first modality of treatment for achalasia. This shift in the treatment algorithm reflects the fact that laparoscopic
Heller myotomy with partial fundoplication outperforms nonsurgical approaches, such as balloon dilatation and intrasphincteric
botulinum toxin injection. 相似文献
85.
B G Gordon S E Strandjord P I Warkentin J Kadushin P F Coccia 《The American journal of pediatric hematology/oncology》1991,13(1):29-33
We have performed bone marrow transplants on four children with severe aplastic anemia who lacked an human leukocyte antigen (HLA)-identical sibling donor. Patients were prepared with cyclophosphamide and 600 cGy fractionated total body irradiation, and then received marrow from a parent donor mismatched for one (two patients), two (one patient), or three (one patient) HLA antigens. All four patients engrafted. One died early of acute graft-versus-host disease. The three others showed sustained complete hematopoietic reconstitution. Two are alive and hematologically normal 43-87 months after transplant. Both have had acute and chronic graft-versus-host disease (CGVHD), and one of the two remains on immunosuppressive drugs. The fourth died at 48 months after transplant of CGVHD. The previous experience with HLA-incompatible marrow transplants is reviewed, and the rationale for this preparative regimen is discussed. Cyclophosphamide and 600 cGy fractionated total body irradiation is an effective preparative regimen for children with severe aplastic anemia receiving transplants from HLA-nonidentical parental donors, allowing engraftment and full hematologic reconstitution. 相似文献
86.
Buffy coat transfusions in neutropenic neonates with presumed sepsis: a prospective, randomized trial 总被引:1,自引:0,他引:1
Neonatal sepsis, accompanied by neutropenia, is associated with a high mortality. To determine whether granulocyte transfusions improve the survival of critically ill neutropenic infants, we prospectively randomized 25 infants to transfusion and nontransfusion groups, matching for birth weight (less than or equal to 1,500 g or greater than 1,500 g). Infants with necrotizing enterocolitis were randomized separately. Neutropenia was established by two successive absolute neutrophil counts less than or equal to 1,500 cells prior to randomization. The transfusion (n = 12) and nontransfusion (n = 13) groups did not differ with respect to clinical or hematologic characteristics. In 23 of 25, bone marrow aspirations were performed to determine the percentage of neutrophil storage pool. Granulocyte transfusions of buffy coats from single units of whole blood (0.1 to 0.9 X 10(9) polymorphonuclear leukocytes per kilogram) were given daily until the absolute neutrophil count increased to more than 1,500/microL. Only five infants, mostly those with necrotizing enterocolitis, required more than one transfusion. A circulating immature to total neutrophil ratio (I:T) greater than or equal to 0.80 was not predictive of an infant with a neutrophil storage pool less than or equal to 7%, and neither an I:T less than 0.80 nor a neutrophil storage pool greater than 7% were predictive of survival. Granulocyte transfusions did not improve survival when either comparing the whole group, those 17 infants with cultures positive for bacteria or viruses, the 19 infants with a circulating I:T greater than or equal to 0.80, or the nine infants with a neutrophil storage pool less than or equal to 7%.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
Ralph R Cook Steven J Bowlin James M Curtis Susan J Hoshaw Patti J Klein Laura L Perkins Eric D Austad 《Annals of plastic surgery》2002,48(1):92-101
Documenting the rate of rupture of silicone breast implants appears to be deceptively easy. Largely because of the phenomenon of "silent rupture," it isn't. The authors explore the various technical biases (selection, misclassification, and confounding) and methodological problems that have plagued much of the research conducted to date. By means of a series of illustrations, they argue that explantation has limited utility. Noninvasive techniques have to be used to gather the proper type of data on the timing and frequency of these events. Only with the proper incidence data will researchers be able to identify better the different mechanisms underlying implant rupture and the relative importance of each. The authors recommend that better and standardized definitions of implant rupture be developed, that greater recognition be given to the technical biases and a greater effort be made to eliminate them from investigations of implant rupture, and that more research be conducted by multidisciplinary teams. Because of the growing awareness of the complexity of this issue, the authors also recommend that properly constituted advisory teams be used to provide comprehensive oversight of future research projects from beginning to end. 相似文献
88.
Background
Laparoscopic fundoplication cures heart-burn and regurgitation in patients with gastroesophageal reflux disease (GERD) but its effect on the chest pain that is also experienced by some patients is less clear. Confusion stems from the fact that it is difficult to determine preoperatively whether the chest pain is actually caused by the reflux. Therefore, we designed a study in patients with GERD and chest pain that would assess the value of pH monitoring in establishing a correlation between the symptom and the disease, the predictive value of pH monitoring on the results of surgical treatment, and the outcome of laparoscopic fundoplication on chest pain in patients with GERD.Methods
Of 487 patients who underwent laparoscopic fundoplication for GERD at our institution between October 1992 and July 2000, 165 (34%) complained of chest pain in addition to heartburn and regurgitation. Their symptoms had been present for an average of 118 months. The pH monitoring tracings were analyzed for a correlation between episodes of reflux and chest pain. The mean length of follow-up was 13 months.Results
Among the 165 patients with chest pain, the relationship between pain and reflux during pH monitoring was as follows: 39 patients (group A) experienced no chest pain during the study; in 28 patients (group B), chest pain correlated with reflux in ≥40% of instances; in 98 patients (group C), chest pain correlated with reflux in ≥40% of instances. Chest pain improved post-operatively in 65% of group A patients, 79% of group B patients, and 96% of group C patients (group C vs A and B: p<0.05). Heartburn and regurgitation resolved or improved in 97% and 95% of patients, respectively.Conclusions
These data show that pH monitoring helped to identify a relationship between chest pain and reflux; and when the two coincided, the chest pain was relieved by antireflux surgery.89.
Sublethal actions of copper in abalone (Haliotis rufescens) as characterized by in vivo 31P NMR 总被引:1,自引:0,他引:1
Viant MR Walton JH TenBrook PL Tjeerdema RS 《Aquatic toxicology (Amsterdam, Netherlands)》2002,57(3):139-151
The sublethal biochemical actions of copper in live, intact red abalone (Haliotis rufescens) were characterized by in vivo 31P nuclear magnetic resonance spectroscopy (NMR). This non-invasive technique is ideal for examining cellular respiration since critical metabolite concentrations, including phosphoarginine ([PA]), inorganic phosphate ([P(i)]) and [ATP], and the arginine kinase (AK) rate constant, can be monitored in real time. Both metabolite concentrations and enzyme rate constants were measured in abalone during 8-h exposures to 66 microg l(-1) (1.04 microM) and 126 microg l(-1) (1.98 microM) copper (as CuCl2). Significant decreases in [PA] and corresponding increases in [P(i)] resulted, while [ATP] remained constant. In controls [PA], [P(i)] and [ATP] all remained unchanged. Furthermore, both copper concentrations induced a significant elevation in the forward AK rate constant over the basal value of 0.020 +/- 0.002 s(-1). Metabolite levels and enzyme rate constants were also measured during 8-h 66 microg l(-1) copper exposures both before and after a 2-week subchronic exposure to 36 microg l(-1) (0.57 microM) copper. Unlike before the subchronic exposure, no significant changes in [PA], [P(i)] or [ATP] were observed after the 36 microg l(-1) copper treatment, compared with controls. This induced tolerance was also evident from the forward AK rate constant data. Finally, copper accumulation was determined in gill, digestive gland and foot muscle samples. Whereas acute exposure only led to significant accumulation in the gill, copper levels in subchronically exposed abalone were significantly elevated in both the gill and digestive gland, and marginally so in foot muscle. Overall, the gill appears to be the primary site of copper accumulation and toxicity, while the foot and adductor muscles maybe secondarily impacted. The observed metabolic changes may result from insufficient oxygen delivery to the muscles, resulting from mucus accumulation or cytological damage at the gill. In conclusion, abalone acutely exposed to copper pollution may develop asphyxial hypoxia. Since their survival is dependent on adherence to rock surfaces, such a reduction of muscle function could ultimately prove fatal. 相似文献
90.
Kalnins I Hart C Ballantyne P Quartaro G Love R Sturis G Pollack P 《Health promotion international》2002,17(3):223-233
We examine children's perceptions of the strategies they would use to resolve community health problems. Qualitative analysis using a grounded theory approach showed that 9- to 10-year-old children could conceptualize a range of solutions to hypothetical community health problems. Children's responses reflected an egocentric perspective, one that was centered on self and peers acting on short-term solutions to the immediate problem. Less frequently, children conceptualized broader structural interventions aimed at removing the problem altogether. Children could name resource persons including their friends, family, school personnel and other people in the community. However, outside of their family and peers, their knowledge was non-specific, i.e. it is doubtful that they would actually be able to access the resources. In light of our findings we discuss several important implications for future research. We note that children are interested in changing community conditions that affect their heath. However, their recognition of their marginalized position in adult society and their perception that adults do not take them seriously may be significant barriers to their participation. We suggest that society must rethink the position and roles that are assigned to children so that their valuable potential is not lost. 相似文献