Scanning acoustic microscopy for characterization of neoplastic and inflammatory lesions of lymph nodes.
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ABSTRACT:
SUBMITTER: Miura K
PROVIDER: S-EPMC3570786 | biostudies-other | 2013
REPOSITORIES: biostudies-other
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Project description:Objective:The purpose of this study was to evaluate the diagnostic performance of acoustic radiation force impulse (ARFI) imaging in differentiating benign from malignant peripheral lymphadenopathy. Materials and Methods:This was a prospective study approved by the Institutional Review Board with financial grant for the same. Ultrasound and ARFI imaging of peripheral lymph nodes were performed and correlated with pathological results, which were used as the reference standard. The virtual touch tissue imaging and virtual touch tissue quantification parameters of ARFI were analyzed in 86 lymph nodes, of which 78 were included in the study. Using receiver operating characteristic curve analysis, the diagnostic usefulness of ARFI values were evaluated with respect to their sensitivity, specificity, and area under the curve. Results:The mean area ratio of benign lymph nodes was 0.88 (±0.2) and that of malignant lymph nodes was 1.17 (±0.14). The mean shear wave velocities (SWV) of benign and malignant lymph nodes were 2.02 m/s (±0.94) and 3.7 m/s (±2.27), respectively. The sensitivity and specificity of virtual touch imaging area ratio in differentiating benign from malignant lymph nodes was 97% and 77%, of SWV was 71% and 70%, and of SWV ratio was 68% and 79%, respectively. Conclusion:As ARFI was found to have a superior diagnostic performance over conventional ultrasound and color Doppler in the characterization of lymph nodes, we recommend its routine use in differentiating benign from malignant nodes.
| S-EPMC7193147 | biostudies-literature
Project description:The spatiotemporal regulation of immune cells in lymph nodes (LNs) is crucial for mounting protective T-cell responses, which are orchestrated by dendritic cells (DCs). However, it is unclear how the DC subsets are altered by the inflammatory milieu of LNs. Here, we show that the inflamed LNs of Listeria-infected mice are characterized by the clustering of neutrophils and monocytes and IFN-? production. Significantly, the early inflammatory responses are coupled with the differentiation of not one, but two types of CD64+CD11c+MHCII+ inflammatory DCs. Through the assessment of chemokine receptor dependency, gene expression profiles, growth factor requirements and DC-specific lineage mapping, we herein unveil a novel inflammatory DC population (we termed 'CD64+ cDCs') that arises from conventional DCs (cDCs), distinguishable from CD64+ monocyte-derived DCs (moDCs) in inflamed LNs. We determined that Listeria-induced type I IFN is a critical inflammatory cue for the development of CD64+ cDCs but not CD64+ moDCs. Importantly, CD64+ cDCs displayed a higher potential to activate T cells than CD64+ moDCs, whereas the latter showed more robust expression of inflammatory genes. Although CD64+ and CD64- cDCs were able to cross-present soluble antigens at a high dose to CD8+ T cells, CD64+ cDCs concentrated and cross-presented a minute amount of soluble antigens delivered via CD64 (Fc?RI) as immune complexes. These findings reveal the role of early inflammatory responses in driving the differentiation of two inflammatory DC subsets empowered with distinct competencies.
| S-EPMC5898896 | biostudies-other
Project description:Scanning acoustic microscopy (SAM) can assess tissue stiffness by calculating the speed of sound (SOS) through tissues. SOS increases as tissue stiffness increases. Sensitivity to protease digestion depends on protein type, concentration, and modification. We analyzed the SOS images of formalin-fixed paraffin-embedded skin sections from elderly, young, diabetic, and nondiabetic subjects, as well as chronic and acute wounds. SAM provided high-resolution histology similar to LM and revealed characteristic SOS alteration following pepsin treatment. SOS values of dermis samples from elderly subjects (especially females) were lower than those of younger adults, which was indicative of age-related dermal softening and loosening. SOS values of elderly females were lower than those of younger females and elderly males. Dermal SOS showed a positive correlation with epidermal thickness. SOS values of epidermis of elderly subjects were higher than those of younger adults and showed a rapid decline 0.5h after protease digestion. Reticular dermis of diabetic patients exhibited greater pepsin resistance than that of nondiabetic patients. Chronic wounds exhibited greater SOS values and pepsin resistance than acute wounds. SOS variation with aging, diabetes mellitus, and wound fibrosis reflected histological and mechanical changes associated with senescence and disease duration. Epidermal thickness reflects age-related changes in dermal stiffness.
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Project description:BACKGROUND: We have evaluated a sensitive screening assay for Mycobacterium tuberculosis (MTB) complex organisms and a specific assay for detecting Mycobacterium bovis DNA in lymph nodes taken from cattle with evidence of bovine tuberculosis. Underlying these series of experiments was the need for a versatile DNA extraction protocol which could handle tissue samples and with the potential for automation.The target for the screening assay was the multi-copy insertion element IS1081, present in 6 copies in the MTB complex. For confirmation of M. bovis we used primers flanking a specific deletion in the genome of M. bovis known as region of difference 4 (RD4). The sensitivity and specificity of these PCRs has been tested on genomic DNA from MTB complex reference strains, mycobacteria other than tuberculosis (MOTT), spiked samples and on clinical material. RESULTS: The minimum detection limits of the IS1081 method was < I genome copy and for the RD4 PCR was 5 genome copies. Both methods can be readily adapted for quantitative PCR with the use of SYBR Green intercalating dye on the RotorGene 3000 platform (Corbett Research). Initial testing of field samples of bovine lymph nodes with visible lesions (VL, n = 109) highlighted two shortfalls of the molecular approach. Firstly, comparison of IS1081 PCR with the "gold standard" of culture showed a sensitivity of approximately 70%. The sensitivity of the RD4 PCR method was 50%. Secondly, the success rate of spoligotyping applied directly to clinical material was 51% compared with cultures. A series of further experiments indicated that the discrepancy between sensitivity of detection found with purified mycobacterial DNA and direct testing of field samples was due to limited mycobacterial DNA recovery from tissue homogenates rather than PCR inhibition. The resilient mycobacterial cell wall, the presence of tissue debris and the paucibacillary nature of some cattle VL tissue may all contribute to this observation. Any of these factors may restrict application of other more discriminant typing methods.A simple means of increasing the efficiency of mycobacterial DNA recovery was assessed using a further pool of 95 cattle VL. Following modification of the extraction protocol, detection rate with the IS1081 and RD4 methods increased to 91% and 59% respectively. CONCLUSION: The IS1081 PCR is a realistic screening method for rapid identification of positive cases but the sensitivity of single copy methods, like RD4 and also of spoligotyping will need to be improved to make these applicable for direct testing of tissue extracts.
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Project description:ObjectivesRheumatoid arthritis (RA) is an immune-mediated inflammatory disease of unknown aetiology. Recent work has shown that systemic autoimmunity precedes synovial inflammation, and animal models have suggested that changes in the lymph nodes may precede those in the synovial tissue. Therefore, we investigated the cellular composition of the lymph node in the earliest phases of inflammatory arthritis.MethodsThirteen individuals positive for immunoglobulin M (IgM) rheumatoid factor and/or anticitrullinated protein antibodies without arthritis were included. Additionally, we studied 14 early arthritis patients (arthritis duration ?6 months, naïve for disease-modifying antirheumatic drugs), and eight healthy controls. All subjects underwent ultrasound-guided inguinal lymph node biopsy. Different T- and B-lymphocyte subsets were analysed by multicolour flow cytometry.ResultsThere was an increase in activated CD69 CD8 T cells and CD19 B cells in early arthritis patients compared with healthy controls. We also observed a trend towards increased CD19 B cells in autoantibody-positive individuals without arthritis compared with healthy controls.ConclusionsThis exploratory study suggests that there is increased immune cell activation within lymph nodes of early arthritis patients as well as in autoantibody-positive individuals at risk of developing RA. This method provides a unique tool to investigate immunological changes in the lymph node compartment in the earliest phases of inflammatory arthritis.
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Project description:BACKGROUND:On the elastic profiles of human teeth after radiotherapy for head and neck cancers, generation of dental complications, which may bring several side effects preventing the quality of life, has not well clarified. Thus, we aimed to show the applicability of using 320?MHz Scanning Acoustic Microscopy (SAM) in the evaluation of the tooth damage acoustically at the micrometer level following radiation therapy, and also in the determination of the safe dose limits to impede severe dental damage. METHODS:This prospective study was performed by SAM employed at 320?MHz by an azimuthal resolution of 4.7??m resolving enamel and dentin. A total of 45 sound human third molar teeth collected between September 2018 and May 2019 were used for the acoustic impedance measurements pre- and post irradiation. Nine samples for each group (control, 2?Gy, 8?Gy, 20?Gy, 30?Gy and 60?Gy) were evaluated to acquire the acoustic images and perform a qualitative analysis. Scanning Electron Microscopy (SEM) images were obtained to establish a relationship between micromechanical and morphological characteristics of the teeth. Statistical analysis was conducted using the Student t-test succeded by Mann-Whitney U investigation (p?<?.05), while SEM images were assessed qualitatively. RESULTS:The analysis included 45 sound teeth collected from men and women 18 to 50?years old. Post irradiation micromechanical variations of human teeth were significant only in the radiation groups of 30?Gy and 60?Gy compared to pre-irradiation group for enamel (7.24?±?0.18 MRayl and 6.49?±?028 MRayl; p?<?0.05, respectively). Besides, the teeth subjected to radiation doses of 20, 30 and 60?Gy represented significantly lower acoustic impedance values relative to non-irradiated group for dentin (6.52?±?0.43 MRayl, 5.71?±?0.66 MRayl and 4.82?±?0.53 MRayl p?<?0.05), respectively. CONCLUSIONS:These results are evidence for a safe acoustic examination device which may be a useful tool to visualize and follow the safe dose limits to impede severe dental damage through the radiation therapy treatment for head and neck cancers.
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Project description:On October 27, 2015, talimogene laherparepvec (T-VEC), a first in class intralesional oncolytic virotherapy, was granted the US Food and Drug Administration approval for the treatment of melanoma in the skin and lymph nodes. Its approval has added yet another therapeutic option to the growing list of effective therapies for melanoma. Though the Phase III OPTiM trial has demonstrated its efficacy as a single agent, the target patient population remains narrow. With numerous effective and tolerable treatments available for unresectable and metastatic melanoma, intralesional therapies such as T-VEC are still finding their niche. T-VEC is now widely accepted as option for treatment; however, its combination with various other agents in an effort to expand its use and synergize with other interventions is still being explored. This article will review the pre-clinical and clinical work that eventually led to the Food and Drug Administration approval of this first-in-class agent, as well as address concerns about clinical application and ongoing research.
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Project description:SIGNIFICANCE:Sentinel lymph node (SLN) biopsy is an important method for metastasis staging in, e.g., patients with malignant melanoma. Tools enabling prompt histopathological analysis are expected to facilitate diagnostics; optical technologies are explored for this purpose. AIM:The objective of this exploratory study was to investigate the potential of adopting multiphoton laser scanning microscopy (MPM) together with fluorescence lifetime analysis (FLIM) for the examination of lymph node (LN) tissue ex vivo. APPROACH:Five LN tissue samples (three metastasis positive and two negative) were acquired from a biobank comprising tissues from melanoma patients. Tissues were deparaffinized and subjected to MPM-FLIM using an experimental MPM set-up equipped with a time correlated single photon counting module enabling FLIM. RESULTS:The data confirm that morphological features similar to conventional histology were observed. In addition, FLIM analysis revealed elevated morphological contrast, particularly for discriminating between metastatic cells, lymphocytes, and erythrocytes. CONCLUSIONS:Taken together, the results from this investigation show promise for adopting MPM-FLIM in the context of SLN diagnostics and encourage further translational studies on fresh tissue samples.
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