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Red light-emitting CdTexSe(1−x) quantum dots (QDs) were synthesized as a new red phosphor for light-emitting diodes. CdTexSe(1−x) QDs were characterized through X-ray diffraction, high-resolution transmission electron microscopy, photoluminescence spectroscopy, and UV–Vis absorption spectroscopy. Results revealed that red-emitting CdTexSe(1−x) QDs were highly crystalline and had good optical properties. A red LED device was fabricated by combining red light-emitting CdTexSe(1−x) QDs as the phosphor with a near-UV InGaN LED chip as the excitation source. The CIE color coordinates of the red LED at (0.6778 and 0.3106) when the reflux time was 1 h. Therefore, CdTexSe(1−x) QDs are good candidates for LED applications.

Objectives The purpose of this study was to analyze the sonographic features of pseudomyxoma peritonei and the ability of preoperative sonography to assess the pathologic grades of this disease. Methods Nineteen patients with pseudomyxoma peritonei who underwent preoperative sonographic examinations were included (9 male and 10 female; age range, 31-70 years). Four patients presented with disseminated peritoneal adenomucinosis, 7 with peritoneal mucinous carcinomatosis with intermediate or discordant features (intermediate-grade disease), and 8 with peritoneal mucinous carcinomatosis. The sonographic characteristics, clinical features, and serum tumor marker levels were recorded and compared among the 3 grades. Results Clinical symptoms and carcinoembryonic antigen, cancer antigen 125 (CA-125), CA-19-9, CA-724, and CA-153 levels were not significantly different among the 3 pathologic grades (P > .05). Ascites, scalloping of the visceral margin, invasive parenchymal nodules, and peritoneal masses were detected in all grades. Disseminated peritoneal adenomucinosis occurred without the finding of an omental cake. The presence of enlarged lymph nodes was more common in peritoneal mucinous carcinomatosis. The diagnosis of pseudomyxoma peritonei was made by preoperative sonography in 1 case. Four cases were diagnosed as ovarian mucinous cystadenoma with rupture. One case was diagnosed as a mucinous appendiceal cyst. Four cases were diagnosed as ascites or encapsulated effusion. One case was misdiagnosed as lymphoma. The others were diagnosed as celiac masses. Conclusions Preoperative sonography can be used to diagnose pseudomyxoma peritonei as long as radiologists are familiar with the imaging features. Although there are overlaps in the sonographic findings among the different grades, some features may aid in separating them.

Purpose To compare the techniques of sonographically (US)-guided percutaneous needle biopsy of the spleen using 18-gauge and 21-gauge needles. Methods Forty-two patients undergoing 43 spleen biopsy procedures for focal lesions (n = 27 [16 single, 11 multiple]) or diffuse splenomegaly (n = 15) were analyzed. Two groups were divided randomly according to needle type: group 1 comprised 25 patients biopsied with an 18-gauge cutting needle for histologic examination; group 2 comprised 17 patients biopsied with a 21-gauge needle for histologic and cytologic examinations. Diagnostic accuracy, complication rate, and number of needle passes were compared between the 2 groups. Results Correct histopathologic diagnosis was obtained in 36 cases, whereas incorrect diagnosis occurred in 6 cases. The accuracy of US-guided spleen biopsy in this series was 85.7%, with 1 patient (2.4%) having postprocedural hemorrhage. Compared with the 21-gauge needle, the 18-gauge needle had higher diagnostic accuracy (P < 0.05), required fewer needle passes (P < 0.05), and there was no significant difference in overall complication rate. Conclusion Because biopsy with an 18-gauge needle yields larger and unfragmented samples with higher diagnostic rate compared with a 21-gauge needle, and no increased rate of major complication requiring surgical intervention, it may be advantageous to use an 18-gauge cutting needle in the US-guided needle biopsy of splenic lesions. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007

OBJECTIVE To conduct a comparative study of the effects of treatment using microwave ablation versus surgical resection on hematogenous dissemination of cancer cells, and on the level of immune cells of the peripheral blood in patients with small primary hepatocellular carcinoma (PHC, ≤5 cm).

To determine the long-term survival and prognostic factors in patients with hepatocellular carcinoma treated with percutaneous microwave ablation.Institutional review board approval and informed consent were obtained. A database of cases of hepatocellular carcinoma in 288 patients (259 men, 29 women; mean age, 54.8 years +/- 11.4 [standard deviation]; age range, 25-82 years) with 477 histologically proved lesions who underwent percutaneous microwave coagulation therapy between May 1994 and October 2002 was retrospectively analyzed. Prognostic factors for survival were evaluated by means of univariate and multivariate analyses.The mean follow-up period after microwave ablation was 31.41 months +/- 20.43 (range, 5-106 months). The 1-, 2-, 3-, 4-, and 5-year cumulative survival rates among all 288 patients were 93%, 82%, 72%, 63%, and 51%, respectively. Ninety-three patients (32%) died. Local recurrence or new tumors occurred in 100 patients (35%). Age (P = .836), sex (P = .073), preablation serum alpha-fetoprotein level (P = .136), and preablation treatment (P = .256) were not related to prognosis, while tumor number (P = .004), tumor size (P.001), Child-Pugh classification (P = .003), tumor differentiation (P = .026), and local recurrence or presence of new tumors (P = .004) significantly affected survival at univariate analysis. At multivariate analysis, only tumor size (P.001), number of nodules (P = .005), and Child-Pugh classification (P = .01) each had a significant effect on survival.With use of microwave ablation, there is a high probability of long-term survival of patients with a single lesion of 4.0 cm or less in maximum diameter and Child-Pugh class A cirrhosis.

To evaluate sequential pathologic and immunologic changes and their prognostic significance after percutaneous microwave coagulation therapy (PMCT) of hepatocellular carcinoma (HCC).Eighty-nine nodules in 82 consecutive patients were studied. The 89 nodules were divided into two groups: a treatment group, with 82 primary nodules (average dimension was 3.4 +/- 1.2 cm) in 82 patients, and a control group, of seven nodules (average dimension was 1.4 +/- 0.6 cm) in seven patients. The criteria for a nodule's inclusion in the control group was that the nodule was one of two nodules in the same patient and that the two nodules were located in different liver lobes. This guarantees that while one nodule is treated by PMCT, the distant one will not be directly affected by the microwave thermal field. The control group nodules were treated after the study was completed. Specimens were taken with ultrasound-guided liver biopsy from the treated nodule and the control nodule, pre- and post-PMCT. Infiltration by T-lymphocytes, B-lymphocytes, NK cells and macrophages in the tumour tissue were observed immunohistochemically using a panel of monoclonal antibodies against CD3, CD45RO, CD20, CD56 and CD68. The extent of immune cell infiltration was compared both before and after PMCT, as well as between the treated and control nodules. The relationship between the prognosis and the extent of immunocyte infiltration was analysed.The patients were followed for 2-26 months (mean 14.6 +/- 6.3) post-treatment. The recurrence rates at 1 and 2 years were 20.4% and 28.1% within the liver in treatment group, respectively. The survival rates at 1 and 2 years were 92.5% and 75.3% for the treatment group. T-cells, NK cells and macrophages increased significantly in both treated and untreated nodules after PMCT, albeit less markedly within untreated nodules when compared to the treated ones. There is a statistically significant correlation between survival outcome and the extent of immunocyte infiltration.For inoperable HCC patients, PMCT is one of the treatment choices shown to be effective. Apart from its tissue coagulation effect, an increased systemic immune response directed against the tumour may also play an important role in improved survival.

To develop a method of dynamic three-dimensional (3-D) simulation of thermal distribution in ultrasound-guided microwave coagulation therapy of liver cancer and to verify its accuracy. The specific absorption rate (SAR) values were established by measuring the temperature in equivalent phantom tests. Those values were different under different power output condition. Dynamic 3-D temperature distributions were reconstructed with a finite-element model. Testing and rectification were performed through animal experiments and clinical trials, respectively. The temperature curves in the experiments corresponded well with simulated ones in vitro--91.4% and 88.9% using single and double electrodes, respectively. The measured coagulated boundary and simulated temperature boundary had a good correspondence in 85.7% of the specimens. In both in vivo experiments and clinical trials, blood perfusion influenced the rise in temperature significantly. Temperature curves between the simulations and actual measured results showed good correspondence--67.8% (19/28) in the patients with hepatocellular carcinoma. Distance between electrodes and combined thermal distributions were both optimized with computer-aided simulation during simultaneous two-electrode coagulation. The results demonstrated that computer-aided simulation of microwave thermal distribution is an accurate and reliable method which provides a theoretical and technical basis for controlling coagulated tissue volume and placement of the electrodes during microwave coagulation therapy of liver cancer.

The aims of this study were to explore individualized treatment method for hepatocellular carcinoma (HCC) patients whose maximum tumor size was less than 5 cm to improve prognosis and survival quality.Thirty cases of primary HCC patients undergoing tumor resection were retrospectively analyzed (resection group). All the tumors were proved as primary HCC with pathologic examination. The patients were divided into two groups according to follow-up results: group A, with tumor recurrence within 1 year after resection; group B, without tumor recurrence within 1 year. Immunohistochemical stainings were performed using 11 kinds of monoclonal antibodies (AFP, c-erbB2, c-met, c-myc, HBsAg, HCV, Ki-67, MMP-2, nm23-H1, P53, and VEGF), and expressing intensities were quantitatively analyzed. Regression equation using factors affecting prognosis of HCC was constructed with binary logistic method. HCC patients undergoing percutaneous microwave coagulation therapy (PMCT) were also retrospectively analyzed (PMCT group). Immunohistochemical stainings of tumor biopsy samples were performed with molecules related to HCC prognosis, staining intensities were quantitatively analyzed, coincidence rate of prediction was calculated.In resection group, the expressing intensities of c-myc, Ki-67, MMP-2 and VEGF in cancer tissue in group A were significantly higher than those in group B (t = 2.97, P = 0.01; t = 2.42, P = 0.030.05; t = 2.57, P = 0.020.05; t = 3.43, P = 0.0040.01, respectively); the expressing intensities of 11 kinds of detected molecules in para-cancer tissue in groups A and B were not significantly different (P0.05). The regression equation predicting prognosis of HCC is as follows: P(1) = 1/[1+e(-(3.663-0.412mycc-2.187Ki-67c-0.397vegfc))]. It demonstrates that prognosis of HCC in resection group was related with c-myc, Ki-67 and VEGF expressing intensity in cancer tissue. In PMCT group, the expressing intensities of c-myc, Ki-67 and VEGF in cancer tissue in group A were significantly higher than those in group B (t = 4.57, P = 0.0000.01; t = 2.08, P = 0.040.05; t = 2.38, P = 0.020.05, respectively); the expressing intensities of c-myc, Ki-67 and VEGF in para-cancer tissue in groups A and B were not significantly different (P0.05). The coincidence rate of patients undergoing PMCT in group A was 88.00% (22/25), in group B 68.75% (11/16), the total coincidence rate was 80.49% (33/41).The regression equation is accurate and feasible and could be used for predicting prognosis of HCC, it helps to select treatment method (resection or PMCT) for HCC patients to realize individualized treatment to improve prognosis.

Our objective was to evaluate the effect of sonography-guided percutaneous microwave ablation of high-grade dysplastic nodules in the cirrhotic liver.From July 1997 to May 2003, 49 histologically proven high-grade dysplastic nodules in 30 patients with liver cirrhosis were treated by microwave ablation. Three patients had concomitant small hepatocellular carcinomas (D3.0 cm), whereas another three had undergone liver segmentectomy for hepatocellular carcinoma 1 year earlier. The mean size of the nodules was 1.8 cm (range, 0.9-4.6 cm). Sixty-eight insertions with 78 applications were administered to the 49 nodules.The follow-up period was 12-82 months (mean, 45.1 +/- 19.0 months). Five patients died during this study: three from advanced hepatocellular carcinoma, one from bleeding in the upper gastrointestinal tract, and another from cerebral hemorrhage. All nodules showed decreased density on unenhanced CT and no enhancement on contrast-enhanced CT after microwave ablation. Posttreatment biopsy performed in 16 patients with 18 nodules 1-3 months after microwave ablation showed no evidence of viable tissue but replacement by fibrotic tissue in all nodules.Percutaneous microwave ablation as a minimally invasive therapy is effective for ablating high-grade dysplastic nodules, thus preventing their potential malignant transformation, which may improve survival. The preliminary data warrant further prospective, randomized studies.

Purpose This study was conducted to evaluate the effectiveness of sonography, especially color Doppler sonography, in the differential diagnosis of cystic hepatic lesions. Methods Ninety-two pathologically or clinically proven hepatic cystic lesions (20 cystic malignancies, 24 abscesses, and 48 simple cysts) were evaluated with gray-scale and color Doppler sonography. The sonographic features were analyzed retrospectively. The percentage, sensitivity, specificity, and positive and negative predictive values of the sonographic features of each disease category were calculated. Results On gray-scale sonography, the simple cysts were easily distinguished from cystic malignancies and abscesses. While no significant differences were found between hepatic cystic malignancies and hepatic abscesses with respect to the number, shape, margin status, and presence of thick wall of the lesion, the presence of septation and mural nodules was significantly higher in the cystic malignancies than in abscesses. The sensitivity and specificity of color Doppler sonography in differentiating cystic malignancies from abscesses and simple cysts were 85% and 96%, respectively. Conclusions Color Doppler sonography provides information about blood flow that supplements that gained on gray-scale sonography, and the presence of color signals in the solid portion of the cystic lesions carries a high diagnostic value in differentiating hepatic cystic malignancies from abscesses and simple cysts. © 2005 Wiley Periodicals, Inc. J Clin Ultrasound 33:100–105, 2005

Microwave-induced tissue coagulation is a new approach for the local ablation of hepatic metastases. The purposes of the study were to analyze therapeutic results and those influencing factors that might be used to predict survival after percutaneous microwave coagulation therapy. SUBJECTS AND METHODS. From July 1995 to March 2002, 74 patients with 149 hepatic metastases were treated with percutaneous microwave coagulation therapy under sonographic guidance. The largest metastasis in each patient ranged from 0.7 to 6.8 cm (mean, 3.12 cm; SD, 1.81 cm). Survival rates and influencing factors were analyzed.The cumulative survival rates of all 74 patients were 91.4% at 1 year, 59.5% at 2 years, 46.4% at 3 years, 29% at 4 years, and 29% at 5 years. Patient age (p = 0.46) and sex (p = 0.12) and site of primary malignancies (p = 0.58) were not related to prognosis, whereas tumor grade (p = 0.01), number of metastases (p = 0.00), tumor size (p = 0.03), and local recurrence or new metastasis (p = 0.00) significantly affected survival as single independent factors. Multivariate analysis revealed that tumor grade (p = 0.03), number of metastases (p = 0.025), and local recurrence or new metastasis (p = 0.04) each had a significant effect on survival. No severe complications occurred.The probability of long-term survival for patients with one or two metastases, well-differentiated tumors, and without recurrence or new metastasis may be significantly higher than for other patients.

The objective of our study was to evaluate the long-term results of percutaneous microwave coagulation therapy for the treatment of hepatocellular carcinoma in a large patient population.Survival rates were determined in 234 patients with 339 nodules of hepatocellular carcinoma who had undergone percutaneous microwave coagulation therapy (208 men, 26 women; mean age, 54.8 years; mean tumor size, 4.1 +/- 1.9 cm; range, 1.2-8.0 cm; mean follow-up period, 27.9 months). Patients were those who had been rejected as candidates for surgery by the surgery department, who fit our study's criteria, and who agreed to participate. After baseline imaging studies were performed, the patients were followed up using the same combination of imaging (sonography, CT, or MR imaging) and posttreatment biopsy.After percutaneous microwave coagulation therapy, color Doppler flow signals disappeared in 92.0% (263/286) of the lesions. No enhancement was apparent in 89.2% (190/213) and 89.1% (41/46) of the lesions on contrast-enhanced CT and MR imaging, respectively. Posttreatment biopsies of 194 nodules showed no evidence of surviving tumor tissue in 180 nodules (92.8%). Resections of six lesions revealed complete tumor necrosis in five. The 1-, 2-, 3-, 4-, and 5-year cumulative survival rates were 92.70%, 81.60%, 72.85%, 66.37%, and 56.70%, respectively. The relationships between survival curves and the degree of hepatocellular carcinoma tumor differentiation and between survival curves and tumor size were statistically significant (p = 0.021). No severe complications were seen.Sonographically guided microwave coagulation proved to be safe and effective for the treatment of hepatocellular carcinoma. This therapy resulted in a high percentage of cases without evidence of residual tumor and satisfactory long-term results.

To evaluate the long-term results of percutaneous microwave coagulation therapy (PMCT) for primary hepatocellular carcinoma.From May 1994 to May 2000, 177 hepatocellular carcinoma patients with 265 nodules underwent PMCT with ultrasound (US) guidance. The tumor size varied from 1.5 to 8.7 cm (median 4.12 + 1.9 cm). Follow-up examination was carried out with colour US, CT, MRI and AFP. 184 nodules were re-biopsied during the follow up of 5 - 74 months (median 29 months).After PMCT, colour Doppler flow signals disappeared in 92.0% (207/225) of patients. No enhancement was observed in 88.5% (138/156) by CT and 88.9% (32/36) by MRI. Re-biopsy of 184 nodules showed complete necrosis in 92.4% (170/184). Six resected lesions showed complete tumor necrosis in 5 and subtotal necrosis in 1. The 1- to 5-year survival rates were 90.1%, 76.9%, 68.3%, 64.2% and 57.8%, respectively. The survival rates of the well differentiated lesions were better than those of the poorly ones (P0.05). But there was not statistical significance between the moderately and the well differentiated ones. The new lesions development rates in 1 to 5 years were 26.1%, 37.8%, 43.5%, 48.6% and 58.9%, respectively. However, there was no severe complication.Ultrasound-guided microwave coagulation is safe and effective for primary hepatocellular carcinoma. It can eliminate tumors less than 5 cm in diameter.

To evaluate the clinical application of gray scale and color Doppler sonography in the diagnosis of hepatic malignant cystic tumors.Characteristics of gray scale and color Doppler sonography were studied in 16 cases of malignant hepatic tumors confirmed by pathology. Tumor size, shape, number of lesion, thickness of cystic wall and echogenecity of the lesion were observed with gray scale sonography. Blood supply of the tumor and its velocity were observed with Color Doppler sonography.One single lesion was common in primary malignancy while multiple lesions signified metastasis. Sonographic findings revealed that the shape of the tumor was spheroid in 8 cases, irregular in 5 and leaf-shaped in 3, with the diameter varying from 1.9 cm to 13.6 cm. Sonography showed malignant cystic tumor with irregular thick wall in 15 cases, multiple septa in 7 cases and papillary projections in 6 on gray scale. Color Doppler flow signal was detected in the irregular thick wall, multiple septa or papillary projections in 14 cases, of which the arterial blood flow signals were demonstrated in 13.Color Doppler is able to clearly detect the blood flow signals in the irregular thick wall, multiple septa or papillary projections, providing an important sign for the diagnosis of hepatic malignant cystic tumors.

To investigate the influencing factors of the local immunity in tissues of hepatocellular carcinoma (HCC) before and after percutaneous microwave coagulation therapy (PMCT).Seventy-eight patients with HCC diagnosed by needle biopsy of liver underwent PMCT. Before the treatment and three and 17 days after the treatment specimens of carcinoma tissues were obtained by ultrasound-guided liver biopsy. The extents of infiltration of CD3(+) cell, natural killer cells (CD56(+)), and macrophages (CD68(+)), and the expression rate of proliferating cell nuclear antigen (PCNA) were evaluated by immunohistochemistry. The relation between the extents of immunocyte infiltration and the clinical parameters was analyzed with multiple regression.Before PMCT infiltration of the three kinds of immunocytes was found in the carcinoma tissues to different degrees with a great variation among individuals. A remarkable increase in the extent of infiltration of the three kinds of immunocytes was found three days after the treatment and continued or remained till the 17th post-PMCT day (P0.01). The post-PMCT extent of immunocyte infiltration was positively correlated with the pre-PMCT extent (CD3(+): r = 0.256, P = 0.005; CD56(+): r = 0.257, P = 0.002; CD68(+): r = 0.275, P = 0.001). A negative correlation was found between the extent of immunocyte infiltration and serum alpha-fetal protein (AFP) and between the extent of immunocyte infiltration and tumor size (for serum AFP, CD3(+): r = -0.075, P = 0.049; CD56(+): r = -0.062, P = 0.041; CD68(+): r = -0.007, P = 0.035; for tumor size, CD3(+): r = -0.074, P = 0.051; CD56(+): r = -0.100, P = 0.012; CD68(+): r = -0.109, P = 0.038). No correlation was found between the extent of immunocyte infiltration and age of patient, Child-Pugh class of tumor, grade of tumor differentiation, and number of tumor. The extent of immunocyte infiltration was lesser in the carcinoma tissues with higher expression rate of PCNA. The extent of immunocyte infiltration was greater in the carcinoma tissues where PCNA expression was negative and carcinoma cells had necrotized but with their structure recognizable. No immunocyte infiltration was found in the necrotic and structureless tumor tissues.The local immunocyte infiltration in patients with HCC was influenced by serum AFP and the grade of tumor cell necrosis pre- and post-PMCT. Destruction of tumor tissue in situs by PMCT is the premise of increase of immunocyte infiltration. Before PMCT improving the immune status of the patients helps enhance the local immune response.

AIM: To explore the effect of c-myc, Ki-67, MMP-2 and VEGF expression on prognosis of hepatocellular carcinoma (HCC) patients undergoing tumor resection. METHODS: Primary HCC patients underwent tumor resection were retrospectively analysed. The maximum size of the tumor was less than 5 cm, there was only one nodule in each patient. No chemoembolization was performed before resection. They were followed up after resection, and the time of recurrence was recorded. They were divided into 2 groups: group A (15 cases): tumor recurrence within 1 year after tumor resection, and group B (15 cases): with or without tumor recurrence 2 years after tumor resection. Pathological slices were made with tumor wax-sample. Immunohistochemistry staining was performed with c-myc, Ki-67, MMP-2 and VEGF monoclonal antibodies. Staining intensity was quantitatively analysed with a pathological diagram-writing analyzing system. The expressing intensity differences of stained molecules in cancer tissue and para-cancer were analysed. RESULTS: c-myc, Ki-67, MMP-2 and VEGF expressing intensities in cancer tissue in group A were higher than those in group B (P values were 0.010, 0.030, 0.022 and 0.004, respectively), but they were not significantly different in para-cancer tissue in groups A and B (P values were 0.334, 0.343, 0.334 and 0.334, respectively). CONCLUSION: The expression of c-myc, Ki-67, MMP-2 and VEGF in cancer tissue is related to the recurrence of HCC after tumor resection.