Characterization of a Raman spectroscopy probe system for intraoperative brain tissue classification

A detailed characterization study is presented of a Raman spectroscopy system designed to maximize the volume of resected cancer tissue in glioma surgery based on in vivo molecular tissue characterization. It consists of a hand-held probe system measuring spectrally resolved inelastically scattered light interacting with tissue, designed and optimized for in vivo measurements. Factors such as linearity of the signal with integration time and laser power, and their impact on signal to noise ratio, are studied leading to optimal data acquisition parameters. The impact of ambient light sources in the operating room is assessed and recommendations made for optimal operating conditions. In vivo Raman spectra of normal brain, cancer and necrotic tissue were measured in 10 patients, demonstrating that real-time inelastic scattering measurements can distinguish necrosis from vital tissue (including tumor and normal brain tissue) with an accuracy of 87%, a sensitivity of 84% and a specificity of 89%.OCIS codes: (170.5660) Raman spectroscopy, (170.6510) Spectroscopy, tissue diagnostics     

A 3D reconstruction algorithm for EIT using a handheld probe for breast cancer detection

A 3D reconstruction algorithm for electrical impedance tomography is presented for determining the distribution of electrical properties inside the body, given electrical measurements made on the surface. A linearized reconstruction algorithm using planar electrode arrays in a handheld probe geometry developed by Mueller et al (1999 IEEE Trans. Biomed. Eng. 46 1379-86) has been refined and extended in this paper. This algorithm is based on linearizing the conductivity about a constant value. We have extended the distance below the electrodes at which a target can be imaged by using a combination of two regularization schemes and a weighted mesh. An appropriate combination of Tikhonov and NOSER regularization produces satisfactory static images of a 2 cm cube placed 2 cm below the array, and difference images of a 1 cm cube 4 cm away from the array. The weighted mesh allows use of fixed regularization parameters for all depths of the target.     

Tumor necrosis factor and its receptors in human ovarian cancer. Potential role in disease progression.

The gene for tumor necrosis factor, TNF, was expressed in 45 out of 63 biopsies of human epithelial ovarian cancer. In serous tumors, there was a positive correlation between level of TNF expression and tumor grade. TNF mRNA was found in epithelial tumor cells and infiltrating macrophages, whereas TNF protein localized primarily to a subpopulation of macrophages within and in close proximity to tumor areas. mRNA and protein for the p55 TNF receptor gene localized to the tumor epithelium and tumor, but not to stromal macrophages. The p75 TNF receptor was confined to infiltrating cells. Cells expressing TNF mRNA were also found in ovarian cancer ascites and TNF protein was detected in some ascitic fluids. In 2 out of 12 biopsies of normal ovary, TNF mRNA was detected in a minority of cells in the thecal layer of the corpus luteum. Serum levels of TNF and its soluble receptor did not correlate with extent of TNF expression in matched biopsies. Northern and Southern analysis revealed no gross abnormality of the TNF gene. The coexpression of TNF and its receptor in ovarian cancer biopsies suggests the capacity for autocrine/paracrine action. TNF antagonists may have therapeutic potential in this malignancy.     

Evaluating the role of IL-12 based therapies in ovarian cancer: a review of the literature

INTRODUCTION: Immunotherapy, in its entirety, represents a promising field at the forefront of cancer. Treatment with potent cytokine IL-12 has provided science with many challenges, but has also demonstrated promise as therapeutic strategy in ovarian cancer. AREAS COVERED: This review examines the anti-tumor mechanism of action of IL-12 and the development of IL-12 as a potential therapeutic option in a variety of malignancies. It also reviews the immunogenicity of ovarian cancer and covers preclinical and clinical trials that have contributed to the advancement of IL-12 as a potential therapy for ovarian malignancy. The obstacles that researchers have overcome and currently face regarding the use of IL-12 in clinical ovarian cancer trials are also discussed. EXPERT OPINION: IL-12, as a therapeutic modality, is mechanistically logical and shows great promise in preclinical trials. Further clinical studies are warranted to optimize the potential of IL-12 as a treatment strategy for ovarian cancer.     

Evaluating the role of IL-12 based therapies in ovarian cancer: a review of the literature

Introduction: Immunotherapy, in its entirety, represents a promising field at the forefront of cancer. Treatment with potent cytokine IL-12 has provided science with many challenges, but has also demonstrated promise as therapeutic strategy in ovarian cancer.

Areas covered: This review examines the anti-tumor mechanism of action of IL-12 and the development of IL-12 as a potential therapeutic option in a variety of malignancies. It also reviews the immunogenicity of ovarian cancer and covers preclinical and clinical trials that have contributed to the advancement of IL-12 as a potential therapy for ovarian malignancy. The obstacles that researchers have overcome and currently face regarding the use of IL-12 in clinical ovarian cancer trials are also discussed.

Expert opinion: IL-12, as a therapeutic modality, is mechanistically logical and shows great promise in preclinical trials. Further clinical studies are warranted to optimize the potential of IL-12 as a treatment strategy for ovarian cancer.     

The characterization of flow signals from tubal and ovarian arteries using intraoperative continuous wave Doppler.

Ovarian vascular Doppler is a promising screening test for early ovarian cancer detection. However, disagreements on flow indices used, flow signal shapes and ovarian vessel localization cause continuing controversy. We aimed at clarifying some of this confusion by directly measuring the adnexal arterial blood flow during laparotomy. A 10-MHz continuous Doppler probe was used to examine adnexal vessels in 24 patients undergoing laparotomy for benign gynecological pathology. Resistance (RI) and pulsatility (PI) indices were calculated for each vessel and the shape of the flow signals was noted. The tubal arteries showed a low-velocity flow pattern with relatively high end-diastolic flow when compared to the ovarian artery signals obtained from the infundibulopelvic ligament.The mean RIs for the tubal artery and ovarian artery in the infundibulopelvic ligament were 0.59 +/- 0.02 and 0.73 +/- 0.02, respectively. The mean PIs for the tubal and ovarian artery in the infundibulopelvic ligament were 1.11 +/- 0.09 and 1.53 +/- 0.1, respectively. The tubal artery showed a significantly lower RI and PI when compared to the ipsilateral ovarian artery at the infundibulopelvic ligament (p < 0.001 and p = 0.002, respectively) and its hilar branches (p = 0.03 for RI and p = 0.03 for PI). We conclude that tubal artery flow signals, which are measured directly for the first time in this study, are characteristic and are distinct from the ovarian artery signals. Tubal artery signals might be erroneously picked up during transvaginal color Doppler sonography of the ovaries, especially in the presence of conditions causing a decreased impedance to blood flow in the pelvis, such as ovarian tumors. Recognizing the flow signal from the tubal artery may help in differentiating ovarian and tubal vessels detected during color Doppler sonography.     

Microscope-integrated intraoperative OCT with electrically tunable focus and heads-up display for imaging of ophthalmic surgical maneuvers

We present novel optical and mechanical designs for a microscope-integrated intraoperative optical coherence tomography (iOCT) system with enhanced function and ergonomics for visualization of ophthalmic surgical maneuvers. Integration of an electrically tunable lens allows rapid focal plane adjustment and iOCT imaging of both anterior and posterior segment tissue microstructures while maintaining parfocality with the ophthalmic surgical microscope. We demonstrate novel visualization of instrument positions relative to tissue layers of interest as colormap overlays onto en face OCT data, which may provide integrative display of volumetric information during surgical maneuvers. Finally, we implement a heads-up display system to provide real-time feedback as proof-of-principle for iOCT-guided ophthalmic surgery.OCIS codes: (170.3880) Medical and biological imaging, (170.4460) Ophthalmic optics and devices, (170.4470) Ophthalmology, (170.4500) Optical coherence tomography, (170.4580) Optical diagnostics for medicine     

Expansion and characterization of T cells transduced with a chimeric receptor against ovarian cancer

Adoptive immunotherapy with genetically modified T lymphocytes is being utilized in clinical trials for the treatment of a broad range of diseases including cancer and HIV infection. To improve on these treatments, and to better understand their mechanisms of action, it is necessary to develop techniques to generate large numbers of cells and characterize the functional heterogeneity of the cells produced. In this study, patient peripheral blood lymphocytes were transduced with a chimeric antigen receptor (MOv-gamma) derived from a mouse monoclonal antibody against folate-binding protein, which is overexpressed on many ovarian cancers. Thus, irrespective of their original specificity, normal human T lymphocytes were redirected to react against ovarian cancer cells. Lymphocytes from five patients were transduced and grown to large numbers, with a median expansion of more than 7000-fold. When proliferation was inadequate, the cells were expanded by stimulation utilizing anti-CD3, IL-2, and irradiated allogeneic PBMCs. The cells maintained their functional ability to recognize ovarian cancer over several months. Cloning of transduced cells was undertaken to determine the level of gene expression and function of individual cells making up the bulk population. Transduced CD4(+) and CD8(+) cell clones were isolated from the bulk and demonstrated antitumor activity. These clones had a diverse repertoire with respect to secretion of cytokines, and individual clones maintained their cytokine profile on subsequent expansion. These studies establish the feasibility of consistently generating large numbers of gene-modified tumor-reactive lymphocytes, with a stable and diverse cytokine repertoire, that could be utilized for patient treatment.     

Auto-fluorescence lifetime and light reflectance spectroscopy for breast cancer diagnosis: potential tools for intraoperative margin detection

This study investigates the use of two spectroscopic techniques, auto-fluorescence lifetime measurement (AFLM) and light reflectance spectroscopy (LRS), for detecting invasive ductal carcinoma (IDC) in human ex vivo breast specimens. AFLM used excitation at 447 nm with multiple emission wavelengths (532, 562, 632, and 644 nm), at which auto-fluorescence lifetimes and their weight factors were analyzed using a double exponent model. LRS measured reflectance spectra in the range of 500-840 nm and analyzed the spectral slopes empirically at several distinct spectral regions. Our preliminary results based on 93 measured locations (i.e., 34 IDC, 31 benign fibrous, 28 adipose) from 6 specimens show significant differences in 5 AFLM-derived parameters and 9 LRS-based spectral slopes between benign and malignant breast samples. Multinomial logistic regression with a 10-fold cross validation approach was implemented with selected features to classify IDC from benign fibrous and adipose tissues for the two techniques independently as well as for the combined dual-modality approach. The accuracy for classifying IDC was found to be 96.4 ± 0.8%, 92.3 ± 0.8% and 96 ± 1.3% for LRS, AFLM, and dual-modality, respectively.     

Conventional and proteomic technologies for the detection of early stage malignancies: markers for ovarian cancer

Our understanding of the tumor microenvironment continues to evolve and allows for the identification of biomarkers that should detect the presence of early stage malignancies. Recent advances in computational analysis and biomedical technologies have come together to elucidate signatures associated with cancer and that are capable of identifying unique tumor-specific proteins. Within the tumor microenvironment, we continue to characterize the proteophysiology of the different steps associated with tumor progression. The urgent need for biomarkers accurately detecting early-stage epithelial ovarian cancer has prompted us, and others, to engage in a search for specific peptide signatures that may discriminate transformed cells from those of the normal ovarian microenvironment. This endeavor also provides new insights into the biology of the disease, which may not only be applicable to detection but may also help to initiate new therapies and optimize patient care.     

血清CA125和CA199检测对卵巢癌诊断应用价值的探讨

目的：通过测定血清中肿瘤标志物 CA125和 CA199水平,探讨其对卵巢癌诊断的应用价值。方法2011年1月至2012年10月确诊的卵巢癌患者61例,卵巢良性疾病患者68例,健康对照者50例,测定血清中 CA125和CA199水平。结果卵巢癌组血清 CA125和 CA199水平均明显高于卵巢良性疾病组和健康对照组,差异有统计学意义（P ＜0．05）;卵巢良性疾病组血清 CA125和 CA199水平与对照组比较,差异无统计学意义（P ＞0．05）;CA125和CA199联合检测的敏感性明显高于 CA125和 CA199单独检测（P ＜0．05）。结论CA125和 CA199水平进行测定及其联合检测对卵巢癌的诊断、分期和治疗有重要意义。     

血清FS及CA125用于卵巢癌诊断的比较研究

目的比较卵泡抑素(Follistatin,FS)及CA125在卵巢癌患者血清中的水平变化及其临床意义。方法分别采用ELISA法和电化学发光法检测卵巢癌、卵巢囊肿患者及健康对照者血清FS及CA125水平,ROC曲线分析二者用于卵巢癌诊断的准确性。结果卵巢癌患者血清FS水平明显高于健康对照组,统计学比较差异显著,P<0.01。以健康对照组血清FS及CA125水平的95%可信区间判断卵巢癌患者血清FS水平,显示血清FS用于卵巢癌诊断时灵敏度为53.3%,特异性为97%;血清CA125的诊断灵敏度为77.8%,特异性为84%;血清FS用于卵巢癌诊断时ROC曲线下面积为0.902,略大于CA125的ROC曲线下面积(0.886)。结论卵巢癌患者血清FS水平升高,与血清CA125水平具有相关性,其用于卵巢癌诊断时准确性与CA125相近,特异性优于CA125。FS是一个很有应用前景的卵巢癌血清诊断标记物,与CA125联合应用有助于降低卵巢癌的误诊率。     

Comparison of image quality between a narrow caliber transesophageal echocardiographic probe and the standard size probe during intraoperative evaluation.

BACKGROUND: Transesophageal echocardiography (TEE) has become an integral part of the evaluation and monitoring of patients during cardiac operation. Until recently, the smallest TEE probe with multiplane imaging measured 13 mm in diameter. This size is now standard for adult TEE probes. Recently, a new TEE probe has become available (MiniMulti TEE probe, Philips Medical Systems, Andover, Mass), which has a diameter of 8 mm. Although using a smaller probe is attractive, the quality of images it generates when used in adults has not yet been examined. OBJECTIVE: The purpose of this study was to compare TEE studies done with both probes. METHODS: After informed consent was obtained, full intraoperative TEE studies were performed in 20 patients with a small pediatric probe. The study was then repeated using a standard adult probe. The studies were read in random order by two experienced echocardiographers blinded to probe used. For each study, 18 anatomic cardiac structures and 5 Doppler patterns were subjectively graded as excellent (1), good (2), fair (3), or poor (4) in quality. The average score for each structure or Doppler profile was computed for each probe. RESULTS: The average score for all findings was lower (better) for the adult TEE probe (1.4 +/- 0.4 vs 1.7 +/- 0.4; P =.003). When each finding was compared separately, several cardiac structures (left ventricle [LV], pericardium, right ventricle [RV], interatrial septum, left atrium, left atrial appendage, mitral valve, aortic valve) had better scores with the adult probe, and the differences for the LV and RV were larger than those for the other findings (LV scores differed by 0.7, P =.0004; RV scores differed by 0.5, P =.01). There was no significant difference between probes when evaluating venous structures (coronary sinus, superior vena cava, pulmonary vein), the thoracic aorta, or the right atrium or tricuspid valve. In addition, Doppler patterns were not significantly different with the two probes. There were two findings that were missed with the small probe and seen with the adult probe (one aortic plaque and one left atrial appendage thrombus). CONCLUSIONS: In the adult, the larger probe provides better images, particularly of the RV and LV. In addition, important findings may be missed with the smaller probe. However, if the adult probe cannot be passed, the pediatric probe is a reasonable alternative.     

线性探针技术用于快速筛查耐多药结核病的研究

目的评价线性探针技术(LPA)快速筛查临床耐多药结核病人的效能。方法应用病例对照研究方法,连续收集326例临床涂阳病人的痰标本,进行传统比例法药物敏感性试验和线性探针技术检测利福平(RFP)和异烟肼(INH)的耐药性,分析线性探针方法对诊断耐多药结核病的敏感度和特异度。结果以比例法为参照,线性探针技术诊断耐多药结核病的敏感度为70%,特异度为97%,结果无显著性差异,报告结果时间为20d,明显低于传统药敏试验报告时间。结论线性探针耐多药检测技术特异性高,快速便捷,可以用于临床耐多药结核病诊断。     

Rapid isothermal detection assay: a probe amplification method for the detection of nucleic acids

Simple, accurate, and stable diagnostic tests are essential to control viral infectious diseases such as avian influenza virus. The current technologies are often inaccessible to people who need them, mainly because of the specialized equipment and the need for highly trained technologists. Here, we describe a rapid isothermal nucleic acid detection assay (RIDA) that can be used to detect both DNA and RNA targets. Using chemically modified probes, we designed a lateral-flow (LF) immunoassay that can be used in combination with RIDA for equipment-free nucleic acid target detection. RIDA is a "probe amplification" assay that uses the single-strand nicking activity of restriction nicking endonucleases to repeatedly cleave synthetic probes hybridizing to the same target sequences. In the RIDA-LF combined assay, chemically labeled probes are covalently conjugated to magnetic microbeads, which is propitious to separate cleaved probes from the reaction solution. The cleaved probes in the solution are then detected with an LF immunoassay. The real-time assay shows that RIDA is able to specifically detect target sequences in 5 to 15 min. The RIDA-LF combined assay can specifically detect nucleic acid targets without sophisticated equipment. In this report, our data suggest that RIDA is a flexible simple assay that could be applied for point-of-care detection. The modified-RIDA described in this report further extends the application of this technology.     

Combined inhibin and CA125 assays in the detection of ovarian cancer

BACKGROUND: The reproductive hormone inhibin has been used as a diagnostic marker of ovarian mucinous and granulosa cell cancers. The aims of this study were to develop a new inhibin immunofluorometric assay (alphaC IFMA) to replace an inhibin RIA as a diagnostic marker of these ovarian cancers and to assess whether the alphaC IFMA in combination with CA125, which detects serous cancers, leads to an improved biochemical diagnosis of all ovarian cancers. METHODS: Serum inhibin concentrations were determined in healthy postmenopausal women (n = 165) and women with ovarian cancers (n = 154), using an inhibin RIA and an alphaC IFMA, which detects inhibin forms containing the alphaC subunit as well as the free alphaC subunit. RESULTS: The alphaC IFMA gave a similar or better discrimination of mucinous (90% vs 71%) and granulosa cell (100% vs 100%) cancers compared with the inhibin RIA. Combination of CA125 and alphaC IFMA values by canonical variate analysis or by multiROC analysis showed that the percentage of all ovarian cancers detected was significantly increased compared with either CA125 or alphaC IFMA alone. CONCLUSIONS: The alphaC IFMA shows a similar or better specificity compared with the RIA, but with increased sensitivity. In combination with CA125, the alphaC IFMA provides an effective dual test for the detection of the majority (90%) of ovarian cancers.     

Mn‐loaded apoferritin: a highly sensitive MRI imaging probe for the detection and characterization of hepatocarcinoma lesions in a transgenic mouse model

Mn‐Apo is a highly sensitive MRI contrast agent consisting of ca. 1000 manganese atoms entrapped in the inner cavity of apoferritin. Part of the metallic payload is in the form of Mn²⁺ ions that endow the nano‐sized system with a very high relaxivity that can be exploited to detect hepatocellular carcinoma in mice. Cellular studies showed that Mn‐Apo is readily taken up by normal hepatocytes via the ferritin transporting route. Conversely, hepatoma cells (HTC) displayed a markedly reduced ability to entrap Mn‐Apo from the culture medium. The i.v. administration of Mn‐Apo into C57BL/6 J mice resulted in a marked liver tissue hyperintensity in T₁‐weighted MR image 20 min after injection. When injected into HBV‐tg transgenic mice that spontaneously develop hepatocellular carcinoma (HCC), Mn‐Apo allowed a clear delineation of healthy liver tissue and tumor lesions as hyperintense and hypointense T₁‐weighted MR images, respectively. Immunohistochemistry analysis correlated Mn‐Apo cellular uptake to SCARA5 receptor expression. When the MRI contrast induced by Mn‐Apo was compared with that induced by Gd–BOPTA (a commercial contrast agent known to enter mouse hepatocytes through organic anion transporters) it was found that only some of the lesions were detected by both agents while others could only be visualized by one of the two. These results suggest that Mn‐Apo may be useful to detect otherwise invisible lesions and that the extent of its uptake directly reports the expression/regulation of SCARA5 receptors. Mn‐Apo contrast‐enhanced MR images may therefore contribute to improving HCC lesion detection and characterization. Copyright © 2012 John Wiley & Sons, Ltd.