Polymer-based cascaded waveguide Bragg grating for blood glucose sensing.

Waveguide Bragg grating (WBG) blood glucose sensing, as a biological sensing technology with broad application prospects, plays an important role in the fields of health management and medical treatment. In this work, a polymer-based cascaded WBG is applied to glucose detection. We investigated photonic devices with two different grating structures cascaded-a crossed grating and a bilateral grating-and analyzed the effects of the crossed grating period, bilateral grating period, and number of grating periods on the sensing performance of the glucose sensor. Finally, the spectral reflectance characteristics, response time, and sensing specificity of the cascaded WBG were evaluated. The experimental results showed that the glucose sensor has a sensitivity of 175 nm/RIU in a glucose concentration range of 0-2 mg/ml and has the advantages of high integration, a narrow bandwidth, and low cost.

Specific antitumour immunity of HIFU-activated cytotoxic T lymphocytes after adoptive transfusion in tumour-bearing mice.

PURPOSE: The aim of this study was to investigate the specific anti-tumour immunity of cytotoxic T lymphocytes (CTL) activated by high-intensity focused ultrasound (HIFU) after adoptive transfer in a murine tumour model. MATERIALS AND METHODS: H22 tumour-bearing mice were treated by either HIFU or sham-HIFU, while naïve syngeneic mice were used as controls. They were sacrificed and the spleens were harvested 14 days after HIFU. T lymphocytes were obtained from the spleens, and then adoptively transferred into 40 mice each bearing a 3-day implanted H22 tumour. On day 14 after adoptive transfer, 10 mice were sacrificed in each group for assessment of the number of tumour-infiltrating T lymphocytes and interferon-gamma (IFN-γ) secreting cells. The remaining 30 mice were continuously observed for 60 days, and tumour growth, progression and survival were recorded. RESULTS: HIFU significantly increased peripheral blood CD3(+), CD4(+) levels and CD4(+)/CD8(+) ratio (P < 0.05), CTL cytotoxicity (P < 0.01) and IFN-γ and TNF-α secretion (P < 0.01) in H22 tumour-bearing mice. Adoptive transfer of HIFU-activated T lymphocytes into the autologous tumour-bearing mice induced a significant increase of tumour-infiltrating T lymphocytes and IFN-γ-secreting cells (P < 0.001). Compared to the control and sham-HIFU groups, HIFU-activated lymphocytes elicited significant inhibition of in vivo tumour growth (P < 0.01) and progression (P < 0.0001), and longer survival time in the tumour-bearing mice (P < 0.001). CONCLUSIONS: HIFU could enhance CTL's specific antitumour immunity. Adoptive transfer of HIFU-activated T lymphocytes could increase local antitumour immunity, and elicit stronger inhibition on tumour growth and progression, with more survival benefit in the autologous tumour-bearing mice.

Mechanism Study of Ultrasonic Vibration-Assisted Microgroove Forming of Precise Hot-Pressed Optical Glass.

Microgroove structures with helical pitches in a wavelength level are increasingly required in optical areas. However, conventional manufacturing techniques generate relatively high stresses during pressing, resulting in poor precision when forming microgrooves. This paper reports on the mechanism of the ultrasonic vibration-assisted microgroove forming of precise hot-pressed optical glass. A finite element (FE) thermocompression model of the viscoelastic material was developed and the entire forming process was numerically simulated using coupled thermal-structural analysis. The analysis of several process parameters was carried out using orthogonal experiments, from which the optimum combination of parameters was selected. The glass thermoforming process is also assisted by ultrasonic vibration. The thermal and mechanical effects of vibration improved material flow and optimized forming results. The average maximum stress in the glass during the forming process was only 3.04 × 10-3 Mpa, while the maximum stress in the hot-pressing stage without ultrasound was 1.648 Mpa. The stress results showed that the material-forming stress is significantly reduced.

T-lymphocytes from focused ultrasound ablation subsequently mediate cellular antitumor immunity after adoptive cell transfer immunotherapy.

Background: Our previous studies found that high-intensity focused ultrasound (HIFU) stimulated tumor-specific T cells in a mouse H22 tumor model, and adoptive transfer of the T cells from HIFU-treated mice could subsequently elicit stronger inhibition on the growth and progression of the implanted tumors. The aim of this study was to investigate the mechanism of T cells from focused ultrasound ablation in HIFU-mediated immunomodulation. Methods: Sixty H22 tumor-bearing mice were treated by either HIFU or sham-HIFU, and 30 naïve syngeneic mice served as controls. All mice were euthanized on day 14 after HIFU and splenic T cell suspensions were obtained in each group. Using an adoptive cell transfer model, a total of 1 × 106 T cells from HIFU treated-mice were intravenously injected into each syngeneic H22 tumor-bearing mouse twice on day 3 and 4, followed by the sacrifice for immunological assessments at 14 days after the adoptive transfer. Results: T cells from HIFU-treated mice could significantly enhance the cytotoxicity of CTLs (p < 0.001), with a significant increase of TNF-α (p < 0.001) and IFN-γ secretion (p < 0.001). Compared to control and sham-HIFU groups, the number of Fas ligand+ and perforin+ tumor-infiltrating lymphocytes (TILs) and apoptotic H22 tumor cells were significantly higher (p < 0.001) in the HIFU group. There were linear correlations between apoptotic tumor cells and Fas ligand+ TILs (r = 0.9145, p < 0.001) and perforin+ TILs (r = 0.9619, p < 0.001). Conclusion: T cells from HIFU-treated mice can subsequently mediate cellular antitumor immunity, which may play an important role in the HIFU-based immunomodulation.

Extracorporeal focused ultrasound surgery for treatment of human solid carcinomas: early Chinese clinical experience.

The objective of this article is to introduce the early Chinese clinical experience of using extracorporeal focused ultrasound (US) surgery (FUS) for the treatment of solid tumors. From December 1997 to October 2001, a total of 1038 patients with solid tumors underwent FUS ablation in 10 Chinese hospitals. The tumors included primary and metastatic liver cancer, malignant bone tumors, breast cancer, soft tissue sarcomas, kidney cancer, pancreatic cancer, abdominal and pelvic malignant tumors, uterine myoma, benign breast tumors, hepatic hemangioma and other solid tumors. In this article, pathologic changes in tumors treated with FUS, real-time diagnostic imaging for targeting, monitoring and assessment of results by follow-up images are presented. Early clinical results and complications of the technique are also reported.

Changes in biologic characteristics of breast cancer treated with high-intensity focused ultrasound.

Proliferation, invasion, immortalization and metastasis are the main malignant characteristics of cancer. Previous studies have shown that high-intensity focused ultrasound (US), or HIFU, can induce irreversible damage both to breast cancer cells and to tumor blood vessels. However, light microscopy alone may not always show this clearly. In this study, molecular biologic techniques were used to examine any changes in molecular markers associated with malignant behavior after exposure to HIFU. A total of 48 women with breast cancer were randomized to a control group (mastectomy) and a HIFU group (HIFU followed by mastectomy). Immunohistochemical staining, messenger RNA (mRNA) in situ hybridization and telomere-repeat amplification protocol-enzyme-linked immunosorbent assay (TRAP-ELISA) techniques were used to detect tumor expression of proliferating cell nuclear antigen (PCNA), cell adhesion molecule CD44v6, matrix metalloproteinase-9 (MMP-9), erbB2 mRNA, and to measure telomerase activity in both groups. The results demonstrated that there were significant alterations in expression of PCNA, CD44v6, MMP-9, erbB2 mRNA, and a dramatic decrease in telomerase activity in the HIFU group. It is concluded that malignant tumor characteristics are arrested by HIFU, and that biologic factors are potential markers for assessing HIFU efficacy.

[High intensity focused ultrasound in the treatment of primary malignant bone tumor].

OBJECTIVE: To develop a new noninvasive limb-salvaging method in the treatment of primary malignant bone tumor in the extremities. METHODS: Forty-four patients with primary malignant bone tumor were treated by extracorporal high intensity focused ultrasound (HIFU) with or without chemotherapy, with a mean follow-up of 17.6 months. RESULTS: The overall survival and complication rates were 84.1% and 18.2%. In 34 patients with stage II b disease, 30 were disease-free, with 2 died of tumor metastasis to brain and lung and 3 developed local recurrence. In 10 patients with stage III b disease, 5 survived with tumor, with 1 developed local recurrence and 5 died of lung metastasis. Thirty-six of 44 patients were > or = 15 points by Enneking system. CONCLUSION: High intensity focused ultrasound combined with chemotherapy for primary malignant bone tumor in the extremity is proved to be effective and safe, preserving good function in the limbs. HIFU may possibly become a new limb-salvaging treatment for this tumor.

[High intensity focused ultrasound alone for malignant solid tumors].

OBJECTIVE: To investigate the efficacy and side-effects of high intensity focused ultrasound (HIFU) in the treatment of malignant solid tumors. METHODS: Thirty such patients who refused surgery and or refractory to chemotherapy, were treated by HIFU alone, with the efficacy and side effects monitored in terms of vital organ signs observation, functional assay of important organs, imaging examinations: digital subtraction angiography (DSA), CT, MRI, single photoemission computed tomography (SPECT), large core needle biopsy, complications or metastasis. RESULTS: After HIFU therapy, the vital signs remained stable and the function of heart, lung, kidney and liver was also normal. DSA images showed that small or larger arteries were not damaged. After a follow-up of 10 - 38 months (23.1 months), 26 patients (87%) have been alive. The volume of the tumor underwent complete regression in 10 patients. Shrinkage of tumor volume >/= 50% was observed in 13. Eight of 13 patients were examined by large core needle biopsy, all showing necrosis and/or fibrosis though 3 patients (10%) had local recurrence. Two of these were retreated again by HIFU and the locally recurrent tumor became well controlled. New metastases developed in 5 patients after HIFU therapy. Two patients suffered from peripheral nerve injuries, most of which have recovered during the follow-up. However, one patient developed skin injury. CONCLUSION: High intensity focused ultrasound alone is effective and safe in the treatment of malignant solid tumors.

High-intensity focused ultrasound tumor ablation activates autologous tumor-specific cytotoxic T lymphocytes.

Previous studies have shown that high-intensity focused ultrasound (HIFU) ablation can enhance host antitumor immune response, though the mechanism is still unknown. In the present study, we investigated whether HIFU ablation could activate tumor-specific T lymphocytes and then induce antitumor cellular immunity. We studied 70 C57BL/6J mice bearing the H(22) tumor; they were randomly divided into a HIFU group and a sham-HIFU group. Of the mice, 35 in the HIFU group underwent HIFU ablation of the H(22) hepatic tumor, and the remaining 35 received a sham-HIFU procedure. In addition, 35 female, naïve syngeneic C57BL/6J mice were used as controls. All mice were sacrificed 14 days after HIFU, and the spleens were harvested. The function of T lymphocytes was determined. As a valuable tool for detecting and characterizing peptide-specific cells, the frequency of MHC class I tetramer/CD8-positive cells was quantified, which could help to determine the response and number of T lymphocytes. The therapeutic effect of the HIFU-activated lymphocytes on tumor-bearing mice was investigated after adoptive transfer of the lymphocytes. The results showed that compared to sham-HIFU and control groups, HIFU ablation significantly increased the cytotoxicity of cytotoxic T lymphocytes (p < 0.05), with a significant increase of IFN-γ and TNF-α secretion (p < 0.001). The frequency of the MHC class I tetramer/CD8-positive cells was significantly higher in the HIFU group (p < 0.05). A stronger inhibition of tumor progression and higher survival rates were observed to be significant after adoptive immunotherapy in the HIFU group as compared to the sham-HIFU and control groups (p < 0.01). It is concluded that HIFU ablation could activate tumor-specific T lymphocytes, thus inducing antitumor cellular immune responses in tumor-bearing mice.

Extracorporeal high intensity focused ultrasound treatment for patients with breast cancer.

PURPOSE: To investigate the safety, efficacy and feasibility of using high-intensity focused ultrasound (HIFU) as a non-invasive treatment for patients with breast cancer. PATIENTS AND METHODS: Twenty-two patients with breast cancer were enrolled into this non-randomized prospective trial. Disease TNM stage was classified as stage I in 4 patients, stage II(A) in 9 patients, stage II(B) in 8 patients, and stage IV in 1 patient. Tumor size ranged from 2 to 4.8 cm in diameter (mean 3.4 cm). All patients received chemotherapy, radiation and tamoxifen, following HIFU for the primary lesions. Outcome measures included radiological and pathologic assessment of the treated tumor, cosmesis, and local recurrence. A cumulative survival rate is calculated by using the Kaplan-Meier method. RESULTS: No severe complications were encountered after HIFU. Post-operative imaging demonstrated positive response and regression of all treated lesions. Follow-up biopsy revealed coagulation necrosis of target tumor and subsequent replacement by fibroblastic tissue. After a median follow-up of 54.8 months, 1 patient died, 1 was lost to follow-up, and 20 were still alive. Two of 22 patients developed local recurrence. Five-year disease-free survival and recurrence-free survival were 95% and 89%, respectively. Cosmetic result was judged as good to excellent in 94% of patients. CONCLUSIONS: HIFU treatment is safe, effective, and feasible for patients with breast cancer. But, large-scale, multiple-center clinical trials will be needed to determine the future role of this novel modality.

Feasibility of US-guided high-intensity focused ultrasound treatment in patients with advanced pancreatic cancer: initial experience.

The study was approved by the university ethics committee, and informed consent was obtained from all patients. The purpose of this study was to prospectively evaluate ultrasonographically guided high-intensity focused ultrasound in the treatment of patients with advanced-stage pancreatic cancer. Eight patients underwent high-intensity focused ultrasound ablation, and laboratory and radiologic examinations were performed after intervention. Changes in symptoms and survival time were noted at follow-up. No complications were observed, and preexisting severe back pain disappeared after intervention. Follow-up images revealed an absence of tumor blood supply and shrinkage of the ablated tumor. Four patients died, and four patients were alive at the time of this writing, with a median survival time of 11.25 months. The authors conclude that high-intensity focused ultrasound ablation is safe and feasible in the treatment of advanced pancreatic cancer.

Advanced hepatocellular carcinoma: treatment with high-intensity focused ultrasound ablation combined with transcatheter arterial embolization.

PURPOSE: To evaluate ultrasonographically (US)-guided high-intensity focused ultrasound ablation combined with transcatheter arterial chemoembolization (TACE) in the treatment of stage IVA hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. From November 1998 to May 2000, 50 consecutive patients with stage IVA HCC (TNM classification, T4N0-1M0) were alternately enrolled in one of two treatment groups: group 1 (n = 26), in which TACE was performed alone, and group 2 (n = 24), in which transcutaneous ablation of HCC with high-intensity focused ultrasound was performed 2-4 weeks after TACE. The tumors were 4-14 cm in diameter (mean, 10.5 cm). Immediate therapeutic effects were assessed at follow-up with Doppler US and computed tomography or magnetic resonance imaging. All patients were followed up for 3-24 months (mean, 8 months) to observe long-term therapeutic effects and complications in both groups. Tumor reduction rates, median survival time, and cumulative survival rates in both groups were calculated by using the unpaired Student t test and Kaplan-Meier method. RESULTS: No severe complication was observed after focused ultrasound ablation, and no unexpected side effects were noted after TACE. Follow-up images showed absence or reduction of blood supply in the lesions after focused ultrasound ablation when compared with blood supply after TACE alone. The median survival time was 11.3 months in group 2 and 4.0 months in group 1 (P = .004). The 6-month survival rate was 80.4%-85.4% in group 2 and 13.2% in group 1 (P = .002), and the 1-year survival rate was 42.9% and 0%, respectively. Median reductions in tumor size as a percentage of initial tumor volume at 1, 3, 6, and 12 months after treatment, respectively, were 28.6%, 35.0%, 50.0%, and 50.0% in group 2 and 4.8%, 7.7%, 10.0%, and 0% in group 1 (P < .01). CONCLUSION: The combination of high-intensity focused ultrasound ablation and TACE is a promising approach in patients with advanced-stage HCC, but large-scale randomized clinical trials are necessary for confirmation.

Extracorporeal high intensity focused ultrasound ablation in the treatment of patients with large hepatocellular carcinoma.

BACKGROUND: High intensity focused ultrasound (HIFU) is a noninvasive treatment modality that induces complete coagulative necrosis of a deep tumor through the intact skin. The current study was conducted to determine the safety, efficacy, and feasibility of extracorporeal HIFU in the treatment of patients with hepatocellular carcinoma (HCC). METHODS: A total of 55 patients with HCC with cirrhosis were enrolled in this prospective, nonrandomized clinical trial. Among them, 51 patients had unresectable HCC. Tumor size ranged from 4 to 14 cm in diameter with mean diameter of 8.14 cm. According to tumor, node, metastasis (TNM) classification, 15 patients corresponded to stage II, 16 to stage IIIA, and 24 to IIIC. All patients had HIFU, and the median number of HIFU session was 1.69. Safety and efficacy of HIFU were assessed in this trial. RESULTS: No severe side effect was observed in the patients treated with HIFU. Follow-up imaging showed an absence of tumor vascular supply and the shrinkage of treated lesions. Serum alpha-fetoprotein returned to normal level in 34% of patients. The overall survival rates at 6, 12, and 18 months were 86.1%, 61.5%, and 35.3%, respectively. The survival rates were significantly higher in patients in stage II than those in stage IIIA (P = .0132) and in stage IIIC (P = .0265). CONCLUSION: As a noninvasive therapy, HIFU appears to be effective, safe, and feasible in the treatment of patients with HCC. It may play an important role in the ablation of large tumors.