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121.
122.
Pinnarine (1), a new macrocyclic alkaloid, was isolated from the black marine sponge Halichondria okadai. The structure was elucidated on the basis of 2D NMR and comparison with the spectra of the co-isolated known halichlorine. Further confirmation of the structure and the absolute configuration was validated by a synthetic method from authentic pinnaic acid and CD analysis. The isolation of pinnarine also suggested a biogenetic pathway from pinnaic acid to halichlorine.  相似文献   
123.

BACKGROUND:

Treatment strategy for patients with adequately staged cT2N0M0 carcinoma of the thoracic esophagus is currently a subject of debate. This study analyzed the largest series of consecutive cT2N0M0 esophageal cancer patients treated with preoperative chemoradiotherapy.

METHODS:

Data from all patients with cT2N0M0 (assessment included endoscopic ultrasonography and computed tomography of the chest and abdomen) thoracic esophageal cancer who were treated with preoperative chemoradiation between 1997 and 2009 were analyzed. The Cox regression model and Kaplan‐Meier plots were used to analyze the data.

RESULTS:

Data from 49 patients were analyzed. The median follow‐up was 28.46 months. Male sex and adenocarcinoma histology predominated. Pathologic complete response was observed 19 (39%) patients. The 10‐year actuarial overall survival (OS) for adenocarcinoma patients was >60%. In the univariate analysis for OS, squamous histology (P = .006), smoking (P = .015), and alcohol consumption (P = .032) were found to be associated with poor OS. In the univariate analysis for disease‐free survival (DFS), squamous histology (P = .009) and smoking (P = .014) were associated with poor DFS. In the multivariate analysis for OS, smoking was an independent prognosticator (P = .02). In the multivariate analysis for DFS, advanced pathologic stage (P = .05) and lymph node metastases (P = .006) were independent prognosticators. Patients with adenocarcinoma (P = .002) and those with pathologic N0 disease had better OS and DFS. Upward stage migration occurred in only 10% of patients.

CONCLUSIONS:

These data suggest that smoking and alcohol influence the long‐term outcome of patients with cT2N0M0 disease. Adenocarcinoma patients treated with trimodality therapy had an excellent actuarial 10‐year OS and a high rate of pathologic complete response. Trimodality therapy should be prospectively compared with primary surgery in these patients. Cancer 2011. © 2010 American Cancer Society.  相似文献   
124.
125.

BACKGROUND:

Metabolic imaging is of interest in esophageal cancer; however, the usefulness of initial standardized uptake value (SUV) in positron emission tomography (PET) is unknown in patients with esophageal or gastroesophageal carcinoma treated with definitive chemoradiotherapy. The authors hypothesized that initial SUV would correlate with patient outcome.

METHODS:

The authors retrospectively analyzed esophageal or gastroesophageal carcinoma patients who had baseline PET and endoscopic ultrasonography in addition to other routine staging. All patients received definitive chemoradiotherapy. Multiple statistical methods were used.

RESULTS:

The authors analyzed 209 consecutive esophageal or gastroesophageal carcinoma patients treated with definitive chemoradiation for outcome; of these, 180 had baseline PET for additional analyses. The median overall survival (OS) for all patients was 20.7 months (95% confidence interval, 18.8‐26.3). Patients with clinical complete response (CR) lived longer than those with less than clinical CR (P < .0001). The median initial SUV was 12.7 (range, 0‐51). Higher initial SUV was associated with longer tumors (P = .0001), higher T‐stage status (P < .0001), positive N‐stage status (P = .0001), higher overall stage (P < .0001), lack of clinical CR (P = .0002), and squamous cell histology (P < .0001). In the univariate analysis, initial SUV was associated with OS (Cox model, P = .016; log‐rank test, P = .002). In the multivariate analysis, initial SUV dichotomized by the median value (P = .024) and tumor grade (P = .016) proved to be independent OS prognosticators. Median initial SUV for clinical CR patients was 10.2, compared with 15.3 for less than clinical CR patients (P = .0058).

CONCLUSIONS:

The data indicate that a higher initial SUV is associated with poorer OS in patients with esophageal or gastroesophageal carcinoma receiving definitive chemoradiation. Upon validation, baseline PET may become a useful stratification factor in randomized trials and for individualizing therapy. Cancer 2011;. © 2011 American Cancer Society.  相似文献   
126.
Tran B  Kopetz S  Tie J  Gibbs P  Jiang ZQ  Lieu CH  Agarwal A  Maru DM  Sieber O  Desai J 《Cancer》2011,117(20):4623-4632

BACKGROUND:

It is hypothesized that BRAF mutant cancers represent a discrete subset of metastatic colorectal cancer (CRC) defined by poorer survival. This study investigates whether BRAF mutant CRC is further defined by a distinct pattern of metastatic spread and explores the impact of BRAF mutation and microsatellite instability (MSI) on prognosis in metastatic CRC.

METHODS:

By using prospective clinical data and molecular analyses from 2 major centers (Royal Melbourne Hospital and The University of Texas MD Anderson Cancer Center), patients with known BRAF mutation status were analyzed for clinical characteristics, survival, and metastatic sites.

RESULTS:

The authors identified 524 metastatic CRC patients where BRAF mutation status was known; 57 (11%) were BRAF mutant tumors. BRAF mutant tumors were significantly associated with right‐sided primary tumor, MSI, and poorer survival (median, 10.4 months vs 34.7 months, P < .001). A distinct pattern of metastatic spread was observed in BRAF mutant tumors, namely higher rates of peritoneal metastases (46% vs 24%, P = .001), distant lymph node metastases (53% vs 38%, P = .008), and lower rates of lung metastases (35% vs 49%, P = .049). In additional survival analyses, MSI tumors had significantly poorer survival compared with microsatellite stable tumors (22.1 months vs 11.1 months, P = .017), but this difference was not evident in the BRAF mutant population.

CONCLUSIONS:

The pattern of metastatic spread observed in this study further defines BRAF mutant CRC as a discrete disease subset. The authors demonstrated that, unlikely early stage disease, MSI is associated with poorer survival in metastatic CRC, although this is driven by its association with BRAF mutation. Cancer 2011;. © 2011 American Cancer Society.  相似文献   
127.
Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency associated with an increased susceptibility to herpesvirus infection and hematologic malignancy as well as a deficiency of NK cell function. It is caused by defective WAS protein (WASp). WASp facilitates filamentous actin (F-actin) branching and is required for F-actin accumulation at the NK cell immunological synapse and NK cell cytotoxicity ex vivo. Importantly, the function of WASp-deficient NK cells can be restored in vitro after exposure to IL-2, but the mechanisms underlying this remain unknown. Using a WASp inhibitor as well as cells from patients with WAS, we have defined a direct effect of IL-2 signaling upon F-actin that is independent of WASp function. We found that IL-2 treatment of a patient with WAS enhanced the cytotoxicity of their NK cells and the F-actin content at the immunological synapses formed by their NK cells. IL-2 stimulation of NK cells in vitro activated the WASp homolog WAVE2, which was required for inducing WASp-independent NK cell function, but not for baseline activity. Thus, WAVE2 and WASp define parallel pathways to F-actin reorganization and function in human NK cells; although WAVE2 was not required for NK cell innate function, it was accessible through adaptive immunity via IL-2. These results demonstrate how overlapping cytoskeletal activities can utilize immunologically distinct pathways to achieve synonymous immune function.  相似文献   
128.
129.
We report a kidney transplant recipient with severe skin‐ and soft‐tissue infection mimicking necrotising fasciitis. Patient failed to respond to empirical antibiotic therapy for presumed bacterial cellulitis. Culture of aspirate from the wound and tissue samples revealed Cryptococcus neoformans. No signs of systemic cryptococcal infection were found. After antifungal treatment and surgical intervention, complete healing was achieved. Clinical and microbiological characteristics of this patient are discussed. Our case indicates that primary cutaneous cryptococcosis must be included in the differential diagnosis of severe cellulitis in solid organ transplant recipients not responding to broad‐spectrum antibiotic regimens. In our case, prompt diagnosis and treatment could dramatically modify the outcome.  相似文献   
130.
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