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91.
Lowery JJ Yeomans L Keyari CM Davis P Porreca F Knapp BI Bidlack JM Bilsky EJ Polt R 《Chemical biology & drug design》2007,69(1):41-47
A series of mu-agonist DAMGO analogs were synthesized and pharmacologically characterized to test the 'biousian' hypothesis of membrane hopping. DAMGO was altered by incorporating moieties of increasing water solubility into the C-terminus via carboxamide and simple glycoside additions. The hydrophilic C-terminal moieties were varied from glycinol in DAMGO (1) to l-serine amide (2), l-serine amide beta-d-xyloside (3), l-serine amide beta-d-glucoside (4), and finally to l-serine amide beta-lactoside (5). Opioid binding and mouse tail-flick studies were performed. Antinociceptive potency (intravenous) increased, passing through a maximum (A(50) approximately 0.2 micromol/kg) for 2 and 3 as membrane affinity versus water solubility became optimal, and dropped off (A(50) approximately 1.0 micromol/kg) for 4 and 5 as water solubility dominated molecular behavior. Intravenous A(50) values were plotted versus hydrodynamic values (glucose units, g.u.) for the glycoside moieties, or the hydrophilic/hydrophobic Connolly surface areas (A(50) versus e(-Awater/Alipid)), and provided either a V-shaped or a U-shaped curve, as predicted by the 'biousian' hypothesis. The mu-selective receptor profile was maintained (K(i)'s = 0.66-1.3 nm) upon modifications at the C-terminus. The optimal 'degree of glycosylation' for the DAMGO peptide message appears to be between 1.25 and 1.75 g.u. (hydrodynamic g.u.), or 0.75 and 0.90 in terms of the surface-derived amphipathicity values. 相似文献
92.
The marine natural chamigrane-type sesquiterpenoid, dactylone, is closely related to secondary metabolites of some edible species of red algae. In the present study, the effect of dactylone was tested on the mouse skin epidermal JB6 P+ Cl41 cell line and its stable transfectants as well as on several human tumor cell lines, including lung (H460), colon (HCT-116), and skin melanomas (SK-MEL-5 and SK-MEL-28). This natural product was effective at nontoxic doses as a cancer-preventive agent, which exerted its actions, at least in part, through the inhibition of cyclin D3 and Cdk4 expression and retinoblastoma tumor suppressor protein (Rb) phosphorylation. The inhibition of these cell cycle components was followed by cell cycle arrest at the G1-S transition with subsequent p53-independent apoptosis. Therefore, these data showed that application of dactylone and related compounds may lead to decreased malignant cell transformation and/or decreased tumor cell proliferation. 相似文献
93.
The role of perforin-mediated apoptosis in lichen planus lesions 总被引:4,自引:0,他引:4
Kastelan M Prpić Massari L Gruber F Zamolo G Zauhar G Coklo M Rukavina D 《Archives of dermatological research》2004,296(5):226-230
Lichen planus is recognized as a T-cell-mediated disease. Histologically, it is characterized by the formation of colloid bodies representing apoptotic keratinocytes. The apoptotic process mediated by CD8+ cytotoxic T lymphocytes (CTLs) and NK cells mainly involves two distinct pathways: the perforin/granzyme pathway and the Fas/FasL pathway. So far, little is known regarding the role of perforin-mediated apoptosis in lichen planus. In the present study, the expression and distribution of perforin, T and NK cell subsets in the epidermis and dermis of lesional and nonlesional lichen planus skin were studied. Skin biopsy specimens from lesional and nonlesional skin of ten patients with lichen planus and eight healthy persons were analysed by immunohistochemistry. Significant accumulation of T cells, particularly of CD4+ and CD8+ subsets, was found in both epidermis and dermis of lichen planus lesions compared with nonlesional and healthy skin. There were no significant differences in the incidence of NK cells (CD16+ and CD56+) between lesional, nonlesional and healthy skin. Perforin expression was significantly upregulated in the epidermis of lichen planus lesions. In conclusion, accumulation of perforin+ cells in the epidermis of lichen planus lesions suggest a potential role of perforin in the apoptosis of basal keratinocytes. 相似文献
94.
95.
Larisa Maria Badau Andrei Dorin Ciocoiu Cristina Marinela Oprean Nusa Alina Segarceanu Adelina Gheju Brigitha Vlaicu 《Current oncology (Toronto, Ont.)》2022,29(3):1890
The safety profile and effectiveness of existing anti-HER2-targeted therapies have not been evaluated in patients with breast cancer and visceral crisis. We report the case of a 26-year-old woman who was diagnosed with advanced HER2-positive breast cancer and initially treated with curative intent therapy in a neoadjuvant setting, using Trastuzumab and Pertuzumab in combination with Docetaxel; her cancer recurred two years later, with liver metastases and pulmonary lymphangitic carcinomatosis, causing visceral crisis. Furthermore, the patient’s clinical status worsened when she developed respiratory failure, hepatomegaly and a severe hepatocytolysis. Since the patient was free of disease more than six months, we started with Paclitaxel half dose because of the hepatic dysfunction, and we gradually reintroduced Trastuzumab and then Pertuzumab. In the meantime, the patient changed her lifestyle by increasing her consumption of fresh fruits and vegetables and fiber and reducing her intake of processed meat, dairy and sugar. As a result, the patient showed a significant improvement in her respiratory symptoms and liver tests in less than two months. Imaging reevaluation showed partial remission of liver metastases and pulmonary lymphangitic carcinomatosis. She underwent seven months of dual anti-HER2 blockade before relapsing cerebrally. Our results suggest that the sequential combination therapy with Trastuzumab, Pertuzumab and Paclitaxel presented in this study, associated with a healthy lifestyle, may be a good management for recurrent HER2-positive breast cancer with pulmonary visceral crisis and severe liver dysfunction. 相似文献
96.
Megan H. Trager Cynthia Chen Sameera Husain Larisa J. Geskin 《The Journal of dermatology》2020,47(5):546-550
Lymphomatoid papulosis (LyP) is a paraneoplastic primary cutaneous CD30+ lymphoproliferative disorder (LPD) that has been associated with malignant lymphomas, most commonly mycosis fungoides (MF). We observed 10 patients with MF who developed severe inflammation after using nitrogen-mustard (NM) gel from 1 to 8 months and who developed LyP. We hypothesized that NM gel produced local inflammation, which induced CD30 expression in malignant T cells in situ leading to the appearance of LyP papules. The high frequency of induction of LyP lesions in patients with severe inflammation while on treatment with NM gel suggests an association between inflammatory stimuli and development of LyP. Our observation provides insight into the pathogenesis of CD30+ LPD. 相似文献
97.
98.
Larisa G. Tereshchenko Alan Cheng MD Barry J. Fetics MSE Joseph E. Marine MD David D. Spragg MD Sunil Sinha MD Hugh Calkins MD Gordon F. Tomaselli MD Ronald D. Berger MD PhD 《Journal of electrocardiology》2010,43(6):548
Background
There is a controversy regarding the association between QRS width and ventricular arrhythmias (VAs). We hypothesized that predictive value of the QRS width could be improved if QRS width were considered in the context of the sum magnitude of the absolute QRST integral in 3 orthogonal leads sum absolute QRST integral (SAI QRST). We explored correlations between QRS width, SAI QRST, and VA in primary prevention implantable cardioverter-defibrillator (ICD) patients with structural heart disease.Methods
Baseline orthogonal electrocardiograms were recorded at rest in 355 patients with implanted primary prevention ICDs (mean age, 59.5 ± 12.4 years; 279 male [79%]). Patients were observed prospectively at least 6 months; appropriate ICD therapies because of sustained VA served as end points. The sum magnitude of the absolute QRST integral in 3 orthogonal leads (SAI QRST) was calculated.Results
During a mean follow-up of 18 months, 48 patients had sustained VA and received appropriate ICD therapies. There was no difference in baseline QRS width between patients with and those without arrhythmia (114.9 ± 32.8 vs 108.9 ± 24.7 milliseconds; P = .230). SAI QRST was significantly lower in patients with VA at follow-up than in patients without VA (102.6 ± 27.6 vs 112.0 ± 31.9 mV·ms; P = 0.034). Patients with SAI QRST (≤145 mV·ms) had a 3-fold higher risk of ventricular tachycardia (VT)/ventricular fibrillation (VF) (hazard ratio [HR], 3.25; 95% confidence interval [CI], 1.59-6.75; P = .001). In the univariate analysis, QRS width did not predict VT/VF. In the bivariate Cox regression model, every 1 millisecond of incremental QRS widening with a simultaneous 1 mV·ms SAI QRST decrease raised the risk of VT/VF by 2% (HR, 1.02; 95% CI, 1.01-1.03; P = .005).Conclusion
QRS widening is associated with ventricular tachyarrhythmia only if accompanied by low SAI QRST. 相似文献99.
Inhibition of indoleamine 2,3-dioxygenase (IDO) enhances elimination of virus-infected macrophages in an animal model of HIV-1 encephalitis 总被引:5,自引:3,他引:5 下载免费PDF全文
Potula R Poluektova L Knipe B Chrastil J Heilman D Dou H Takikawa O Munn DH Gendelman HE Persidsky Y 《Blood》2005,106(7):2382-2390
Indoleamine 2,3-dioxygenase (IDO) is the rate-limiting enzyme in the kynurenine pathway of tryptophan metabolism. IDO activity is linked with immunosuppression by its ability to inhibit lymphocyte proliferation, and with neurotoxicity through the generation of quinolinic acid and other toxins. IDO is induced in macrophages by HIV-1 infection, and it is up regulated in macrophages in human brain tissue with HIV-1 encephalitis (HIVE). Using a model of HIVE, we investigated whether IDO inhibitor 1-methyl-d-tryptophan (1-MT) could affect the generation of cytotoxic T lymphocytes (CTLs) and clearance of virus-infected macrophages from the brain. Severe combined immunodeficient mice were reconstituted with human peripheral blood lymphocytes, and encephalitis was induced by intracranial injection of autologous HIV-1-infected monocyte-derived macrophages (MDMs). Animals treated with 1-MT demonstrated increased numbers of human CD3+, CD8+, CD8+/interferon-gamma+ T cells, and HIV-1(gag/pol)-specific CTLs in peripheral blood compared with controls. At week 2 after MDM injection in the basal ganglia, mice treated with 1-MT showed a 2-fold increase in CD8+ T lymphocytes in the areas of the brain containing HIV-1-infected MDMs compared with untreated controls. By week 3, 1-MT-treated mice showed 89% reduction in HIV-infected MDMs in brain as compared with controls. Thus, manipulation of immunosuppressive IDO activity in HIVE may enhance the generation of HIV-1-specific CTLs, leading to elimination of HIV-1-infected macrophages in brain. 相似文献
100.
Kulnigg S Stoinov S Simanenkov V Dudar LV Karnafel W Garcia LC Sambuelli AM D'Haens G Gasche C 《The American journal of gastroenterology》2008,103(5):1182-1192
BACKGROUND AIMS: Anemia is a common complication of inflammatory bowel diseases (IBD) This multicenter study tested the noninferiority and safety of a new intravenous iron preparation, ferric carboxymaltose (FeCarb), in comparison with oral ferrous sulfate (FeSulf) in reducing iron deficiency anemia (IDA) in IBD.
METHODS: Two hundred patients were randomized in a 2:1 ratio (137 FeCarb:63 FeSulf) to receive FeCarb (maximum 1,000 mg iron per infusion) at 1-wk intervals until the patients' calculated total iron deficit was reached or FeSulf (100 mg b.i.d.) for 12 wk. The primary end point was change in hemoglobin (Hb) from baseline to week 12.
RESULTS: The median Hb improved from 8.7 to 12.3 g/dL in the FeCarb group and from 9.1 to 12.1 g/dL in the FeSulf group, demonstrating noninferiority ( P = 0.6967). Response (defined as Hb increase of >2.0 g/dL) was higher for FeCarb at week 2 ( P = 0.0051) and week 4 ( P = 0.0346). Median ferritin increased from 5.0 to 323.5 μg/L at week 2, followed by a continuous decrease in the FeCarb group (43.5 μg/L at week 12). In the FeSulf group, a moderate increase from 6.5 to 28.5 μg/L at week 12 was observed. Treatment-related adverse events (AEs) occurred in 28.5% of the FeCarb and 22.2% of the FeSulf groups, with discontinuation of study medication due to AEs in 1.5% and 7.9%, respectively.
CONCLUSIONS: FeCarb is effective and safe in IBD-associated anemia. It is noninferior to FeSulf in terms of Hb change over 12 wk, and provides a fast Hb increase and a sufficient refill of iron stores. 相似文献
METHODS: Two hundred patients were randomized in a 2:1 ratio (137 FeCarb:63 FeSulf) to receive FeCarb (maximum 1,000 mg iron per infusion) at 1-wk intervals until the patients' calculated total iron deficit was reached or FeSulf (100 mg b.i.d.) for 12 wk. The primary end point was change in hemoglobin (Hb) from baseline to week 12.
RESULTS: The median Hb improved from 8.7 to 12.3 g/dL in the FeCarb group and from 9.1 to 12.1 g/dL in the FeSulf group, demonstrating noninferiority ( P = 0.6967). Response (defined as Hb increase of >2.0 g/dL) was higher for FeCarb at week 2 ( P = 0.0051) and week 4 ( P = 0.0346). Median ferritin increased from 5.0 to 323.5 μg/L at week 2, followed by a continuous decrease in the FeCarb group (43.5 μg/L at week 12). In the FeSulf group, a moderate increase from 6.5 to 28.5 μg/L at week 12 was observed. Treatment-related adverse events (AEs) occurred in 28.5% of the FeCarb and 22.2% of the FeSulf groups, with discontinuation of study medication due to AEs in 1.5% and 7.9%, respectively.
CONCLUSIONS: FeCarb is effective and safe in IBD-associated anemia. It is noninferior to FeSulf in terms of Hb change over 12 wk, and provides a fast Hb increase and a sufficient refill of iron stores. 相似文献