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71.
The objective of this Phase II study was to evaluate the pharmacodynamic and immune effects of intratumorally administered recombinant human interleukin-12 (IL-12) on regional lymph nodes, primary tumor, and peripheral blood. Ten previously untreated patients with head and neck squamous cell carcinoma were injected in the primary tumor two to three times, once/week, at two dose levels of 100 or 300 ng/kg, before surgery. We compared these patients with 20 control (non-IL-12-treated) patients. Toxicity was high, with unexpected dose-limiting toxicities at the 300 ng/kg dose level. Dose-dependent plasma IFN-gamma and IL-10 increments were detected. These cytokine levels were higher after the first injection than after the subsequent injections. A rapid, transient reduction in lymphocytes, monocytes, and all lymphocyte subsets, especially natural killer cells, was observed, due to a redistribution to the lymph nodes. In the enlarged lymph nodes of the IL-12-treated patients, a higher percentage of natural killer cells and a lower percentage of T-helper cells were found compared with control patients. The same pattern was detected in the infiltrate in the primary tumor. Real-time semiquantitative PCR analysis of peripheral blood mononuclear cells in the peripheral blood showed a transient decrease of T-bet mRNA. Interestingly, the peripheral blood mononuclear cells in the lymph nodes showed a 128-fold (mean) increase of IFN-gamma mRNA. A switch from the Th2 to a Th1 profile in the lymph nodes compared with the peripheral blood occurred in the IL-12-treated patients. In conclusion, in previously untreated head and neck squamous cell carcinoma patients, recombinant human IL-12 intratumorally showed dose-limiting toxicities at the dose level of 300 ng/kg and resulted in measurable immunological responses locoregionally at both dose levels.  相似文献   
72.
PURPOSE: Gastrointestinal stromal tumors (GISTs) represent a distinctive (but histologically heterogeneous) group of neoplasms, the malignant potential of which is often uncertain. To determine the prognostic relevance of p16INK4 alterations in GISTs, we investigated a larger group of GISTs and correlated the genetic findings with clinicopathological factors and patient survival. MATERIAL AND METHODS: We evaluated the methylation status of the promotor by methylation-specific polymerase chain reaction (PCR), the presence of mutations by PCR-SSCP-sequencing, the loss of heterozygosity at the p16INK4 locus (using the c5.1 marker), and the immunohistochemical expression of p16INK4 protein in 43 GISTs in 39 patients. RESULTS: p16INK4 alterations were found in 25 of 43 GISTs (58.1%), with benign, borderline, or malignant GISTs showing no differences in the type and frequency of alteration. p16INK4 alterations were correlated with a loss of p16INK4 protein expression (P <.01). Patients who had tumors with p16INK4 alterations had a poorer prognosis than patients with tumors without such alterations (P =.02). There was a high predictive value for p16INK4 alterations only in the group of benign and borderline GISTs (P <.01) with regard to clinical outcome. Univariate Cox's proportional hazard regression analysis revealed a strong correlation between p16INK4 alterations, tumor size, mitotic index, and overall survival (P <.02), whereas multivariate Cox's analysis confirmed only p16INK4 alterations as an independent prognostic factor. CONCLUSION: We believe that the evaluation of p16INK4 alteration status is a helpful prognosticator, particularly in the benign and borderline groups of GISTs.  相似文献   
73.
This report reviews the current theories on the deposition of inhaled particulates in the human nose. The inhalation of particulates represents a challenge to the upper respiratory tract. The concentration of airborne particulates and pollutants varies between occupational and nonoccupational exposure. Regional deposition of potentially hazardous inhaled material determines the local and systemic toxicity. In vitro experiments using casting and molding techniques with water dye models or laser Doppler anemometry indicate that nasal airflow is determined by the size of the nasal valve and the turbinates. The main airstream during inspiration passes through the lower nasal passage. Filtration capacity of the human nose can be expressed mathematically or experimentally. In vivo experiments applying monodisperse or polydisperse aerosols during single or multiple respiratory cycles have shown by using microscopic or laser-optic identification that particles larger than 3µm have a maximum deposition in the anterior part of the nose (nasal valve). Particles smaller than 3 µm and larger than 0.5 µm are filtered by the nasal mucosa and transported by cilia propulsion to the nasopharynx. The filtration for particles smaller than 0.5 µm is low. They seem to pass easily into the lower respiratory tract. This knowledge has an impact on nasal septal surgery and rhinoplasty. By influencing the structure of the nasal valve and the lower turbinates, the filtration capacity of the nose can be significantly decreased.  相似文献   
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INTRODUCTION: Some 5-10% of all cases of breast cancer and ovarian cancer have a hereditary genesis. In the setting of an interdisciplinary cancer genetics clinic, a study of the age at which patients first take advantage of early cancer detection (ECD) facilities was conducted in order to assess the influence of familial risk on health issues. METHODS: The study included 556 women who fulfilled the inclusion criteria (IC) for genetic analysis of the BRCA1 and BRCA2 genes, as well as 205 who did not meet these criteria but attended the primary consultation. RESULTS: Consulters who met the inclusion criteria took advantage of nearly all methods of ECD at an earlier time than women who did not. A comparison of consulters with or without breast cancer showed that those without breast cancer participated in all methods of ECD at an earlier time. CONCLUSION: Methods of improving and increasing participation in ECD facilities, and of encouraging women who are at risk to start on such programs at a younger age, need to be discussed. In this study, familial risk already resulted in a younger age of uptake of ECD facilities.  相似文献   
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The analysis of circulating tumor DNA (ctDNA) is at the threshold of implementation into standard care for colorectal cancer (CRC) patients. However, data about the clinical utility of liquid profiling (LP), its acceptance by clinicians, and its integration into clinical workflows in real‐world settings remain limited. Here, LP tests requested as part of routine care since 2016 were retrospectively evaluated. Results show restrained request behavior that improved moderately over time, as well as reliable diagnostic performance comparable to translational studies, with an overall agreement of 91.7%. Extremely low ctDNA levels at < 0.1% in over 20% of cases, a high frequency of concomitant driver mutations (in up to 14% of cases), and ctDNA levels reflecting the clinical course of disease were revealed. However, certain limitations hampering successful translation of ctDNA into clinical practice were uncovered, including the lack of clinically relevant ctDNA thresholds, appropriate time points of LP requests, and integrative evaluation of ctDNA, imaging, and clinical findings. In conclusion, these results highlight the potential clinical value of LP for CRC patient management and demonstrate issues that need to be addressed for successful long‐term implementation in clinical workflows.  相似文献   
78.
Open in a separate window OBJECTIVESTo evaluate outcomes after thoracic endovascular aortic repair in young patients sustaining traumatic blunt aortic injury (BAI) using iliac extension stent-grafts because of small aortic diameters measuring <24 mm.METHODSRetrospective analysis regarding clinical presentation, trauma management, endovascular techniques and outcome of patients with a small descending aorta involving an iliac extension stent-graft to treat traumatic BAI.RESULTSAmong 48 patients who suffered a BAI and underwent thoracic endovascular aortic repair, 7 received iliac extension stent-grafts. They were 27.4/[standard deviation (SD): −13.1] years old and 6 out of 7 were male. The iliac extension stent-graft was used as distal stent-graft, and a thoracic stent-graft was used in most patients as proximal extension. We achieved overall technical success in all patients during a procedure lasting 92.6 (SD: 54.9) min. One patient died 2 days after the endovascular procedure of hypoxic brain injury, and another died after 17 days of liver failure. That patient had also suffered a spinal cord injury following the procedure, as the stent-graft had been deployed in Ishimaru Zone 2, and the carotid to subclavian bypass had to be omitted because of his critical condition. Control computed tomographic angiographs was available in 6 patients after 7.7 (SD: 5.1) days and showed no endoleak. The surviving patients were discharged after 18.4 (SD: 13.4) days.CONCLUSIONSTreating traumatic BAI using iliac extension stent-grafts in young patients with small aortic diameters is feasible. We observed no mortality caused by the BAI or related to endovascular therapy within this small patient cohort.  相似文献   
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Hepatocellular carcinoma (HCC) is a major cause of morbidity and mortality worldwide and the fastest-rising course of cancer-related death in the United States....  相似文献   
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