Contralateral Tissue Research Articles

Brain tumor acidification using drugs simultaneously targeting multiple pH regulatory mechanisms.

Non-invasively distinguishing aggressive from non-aggressive brain tumors is an important clinical challenge. Intracellular pH (pHi) regulation is essential for normal cell function and is normally maintained within a narrow range. Cancer cells are characterized by a reversed intracellular to extracellular pH gradient, compared to healthy cells, that is maintained by several distinct mechanisms. Previous studies have demonstrated acute pH modulation in glioblastoma detectable by chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) after blocking individual pH regulatory mechanisms. The purpose of the current study was to simultaneously block five pH regulatory mechanisms while also providing glucose as an energy substrate. We hypothesized that this approach would increase the acute pH modulation effect allowing the identification of aggressive cancer. Using a 9.4T MRI scanner, CEST spectra were acquired sensitive to pHi using amine/amide concentration independent detection (AACID). Twelve mice were scanned approximately 11 ± 1days after implanting 105 U87 human glioblastoma multiforme cells in the brain, before and after intraperitoneal injection of a combination of five drugs (quercetin, cariporide, dichloroacetate, acetazolamide, and pantoprazole) with and without glucose. Two hours after combination drug injection there was a significant 0.1 ± 0.03 increase in tumor AACIDvalue corresponding to a 0.4 decrease in pHi. After injecting the drug combination with glucose the AACID value increased by 0.18 ± 0.03 corresponding to a 0.72 decrease in pHi. AACID values were alsoslightly increased in contralateral tissue. The combined drug treatment with glucose produced a large acute CEST MRI contrast indicating tumor acidification, which could be used to help localize brain cancer and monitor tumor response to chemotherapy.

Pioglitazone abrogates testicular damage induced by testicular torsion/detorsion in rats.

Objective(s):Testicular torsion/detorsion (T/D) is a well-known cause for infertility. Pioglitazone is an agonist of peroxisome proliferator activated receptor-gamma (PPAR-γ). Previous studies have shown that pioglitazone has anti-inflammatory, antioxidant and antiapoptotic properties. The present study hypothesized that pioglitazone may be protective against the testicular T/D tissue insults, and the possible pathophysiological mechanisms involved in this effect were also investigated. Materials and Methods:Rats were randomly divided into four groups: sham group, T/D group where testicular torsion was performed for 4 hr followed by 4 hr of detorsion and two pioglitazone-treated groups (1 mg/kg and 3 mg/kg, by single intraperitoneal injection 30 min prior to detorsion). At the end of reperfusion period, blood, ipsilateral and contralateral testicular tissue samples were obtained for biochemical and histopathological examination. Results:Pioglitazone reduced oxidative tissue damages, inflammatory mediators, and apoptotic markers and enhanced the total antioxidant status, and AMP-activated protein kinase level. Moreover, pioglitazone improved spermatogenesis evidenced by increased Johnsen’s score and reversed the histopathological damages induced by testicular T/D. The effects of pioglitazone were higher with the dose of 3 mg/kg.Conclusion:Pioglitazone exhibited a protective effect against the deleterious actions of testicular T/D. This beneficial potential of pioglitazone may be attributed to its antioxidant, anti-inflammatory and antiapoptotic properties, which was more obvious with the dose of 3 mg/kg. Pioglitazone may be a promising therapy for testicular T/D.

Analysis of normal tissues adjacent to the tumour-specific expressed genes in breast cancer

Normal tissues adjacent to the tumour (NAT) are widely used as controls in comparative studies to search for cancer-associated genes. However, the gene expression profiles between NAT and non-tumour-bearing tissues are different. The presence of NAT-specific expressed genes often hinders traditional transcriptional profiles studies. Further, studies on the differences in gene expression profiles between NAT and tumour-free tissues are infrequently performed. In this study, we sequenced and analysed the transcriptomes of tumour tissues (T), matched NAT and contralateral breast normal tissues (CBN) of 14 breast cancer patients, and identified 102 differentially expressed genes (DEGs) between CBN and NAT. Gene enrichment and protein-protein interaction (PPI) analyses revealed that these DEGs are significantly enriched in TNF (tumour necrosis factor) signalling and EMT (epithelial-mesenchymal transition) gene sets closely associated with oncogenesis. Comparative analyses of the transcriptomic profiles between NAT and CBN, NAT and T identified 23 NAT-specific highly-expressed genes, namely tumour-adjacent speci?cally activated (TASA) genes. These genes were significantly enriched in TNF signalling gene set, and 15 of which have not been previously reported. The results indicate that TASA genes are common in adjacent tissues and are related to the TNF signalling in the immune system. The tumour-adjacent tissues harbour tumour-like expressed genes that could contribute to tumour initiation but are often missed in NAT-T pair-wise studies.

Differential expression of RET isoforms in normal thyroid tissues, papillary and medullary thyroid carcinomas.

We investigated the expression of RET9 and RET51 isoforms in medullary (MTC), papillary (PTC) thyroid carcinoma, normal thyroid tissues, and pheochromocytoma (PHEO) to verify if these isoforms are present also in follicular thyroid cell-derived tissues, and if there is a differential expression of RET9 and RET51 in MTC. Nineteen patients with MTC, 18 patients with PTC, 18 samples of contralateral normal thyroid tissues, and 5 cases of PHEO were included in this study. RET isoform expression was studied by real-time RT-PCR. All MTCs and PHEOs were positive for RET9 and RET51. Fourteen/eighteen (77.7%) PTC cases were positive for RET9 and/or RET51, and four were positive for only one of the genes. In normal thyroid tissues, 3/18 (16.7%) cases were negative for both isoforms, 4/18 (22.2%) were positive for both, and 11/18 (61.1%) were positive for only one. RET isoforms were expressed at different levels in MTC, PHEO, PTC, and normal thyroid tissues: RET9 expression was higher in PHEO than in MTC, PTC, and normal thyroid tissues. RET9 expression was also higher in MTC than in PTC and normal thyroid tissues. No difference was observed between PTC and normal thyroid tissues. A similar pattern of expression was observed for RET51. In addition, RET51 was significantly more expressed than RET9 in MTC, while RET9 was the predominant isoform in PHEO. Our study documented the expression of the RET9 and RET51 isoforms in normal thyroid and PTC tissues. RET9 and RET51 isoforms were also present in MTC and PHEO. RET51 expression was higher than RET9 expression in MTC, while there was no difference in the expression of these two isoforms in PTC and normal thyroid tissues. RET9 was more highly expressed than RET51 in PHEOs.

A multiparametric [18F]FDG PET/MRI diagnostic model including imaging biomarkers of the tumor and contralateral healthy breast tissue aids breast cancer diagnosis

PurposeTo develop a multiparametric [18F]FDG positron emission tomography/magnetic resonance imaging (PET/MRI) model for breast cancer diagnosis incorporating imaging biomarkers of breast tumors and contralateral healthy breast tissue.MethodsIn this prospective study and retrospective data analysis, 141 patients (mean 57 years) with an imaging abnormality detected on mammography and/or ultrasound (BI-RADS 4/5) underwent combined multiparametric [18F]FDG PET/MRI with PET/computed tomography and multiparametric MRI of the breast at 3 T. Images were evaluated and the following were recorded: for the tumor, BI-RADS descriptors on dynamic contrast-enhanced (DCE)-MRI, mean apparent diffusion co-efficient (ADCmean) on diffusion-weighted imaging (DWI), and maximum standard uptake value (SUVmax) on [18F]FDG-PET; and for the contralateral healthy breast, background parenchymal enhancement (BPE) and amount of fibroglandular tissue (FGT) on DCE-MRI, ADCmean on DWI, and SUVmax. Histopathology served as standard of reference. Uni-, bi-, and multivariate logistic regression analyses were performed to assess the relationships between malignancy and imaging features. Predictive discrimination of benign and malignant breast lesions was examined using area under the receiver operating characteristic curve (AUC).ResultsThere were 100 malignant and 41 benign lesions (size: median 1.9, range 0.5–10 cm). The multivariate regression model incorporating significant univariate predictors identified tumor enhancement kinetics (P = 0.0003), tumor ADCmean (P < 0.001), and BPE of the contralateral healthy breast (P = 0.0019) as independent predictors for breast cancer diagnosis. Other biomarkers did not reach significance. Combination of the three significant biomarkers achieved an AUC value of 0.98 for breast cancer diagnosis.ConclusionA multiparametric [18F]FDG PET/MRI diagnostic model incorporating both qualitative and quantitative parameters of the tumor and the healthy contralateral tissue aids breast cancer diagnosis.

The anti-nociceptive effects of Porphyromonas gingivalis lipopolysaccharide

ObjectiveThe objective of this study was to assess the effect of Porphyromonas gingivalis lipopolysaccharide (PG LPS) on acute pain-related behaviour induced in rats and to measure its impact on the levels of pro-inflammatory cytokines (IL-1β, IL-6) and anti-inflammatory (IL-10) cytokines. DesignThe Brennan model was used to induce acute pain like signs in rats' hind paw. Twenty-four hours following the surgery the rats were divided into 5 groups and the affected paws were injected with 0.2 m l of one of three commercialized forms PG LPS doses (high - 1 mg/ml, medium - 0.6 mg/m l and low - 0.2 mg/m l), diclofenac sodium (1 mg/kg) or saline. Tactile allodynia, mechanical hyperalgesia, body temperature and paw swelling were assessed at baseline, 24 h postoperatively and 2 h after the paw injection. The affected and contra-lateral paw tissue was assessed for the mentioned above cytokines levels employing enzyme-linked immunosorbent assay. ResultsThis study may suggest that PG LPS can reduce pain like behaviour via increased levels of anti-inflammatory cytokine IL-10 (5900 ± 748, p < 0.05). The high PG LPS dose and diclofenac reduced the tactile allodynia and mechanical hyperalgesia significantly (42.2 ± 4 and1.6 ± 0.3, p < 0.05). PG LPS high dose increase IL-10 levels while diclofenac reduces IL-1β levels significantly (5900 ± 748 and 1760 ± 271.2). The LPS administration had no effect on paw swelling and did not increase rat’s body temperature. ConclusionThe results demonstrated that PG LPS local application could possess anti- nociceptive properties, which at least in part is mediated by an increase in IL-10 levels.

Role of acute-phase protein ORM in a mice model of ischemic stroke.

The only Food and Drug Administration-approved treatment for acute ischemic stroke is tissue plasminogen activator, and the discovery of novel therapeutic targets is critical. Here, we found orosomucoid (ORM), an acute-phase protein mainly produced by the liver, might act as a treatment candidate for an ischemic stroke. The results showed that ORM2 is the dominant subtype in mice normal brain tissue. After middle cerebral artery occlusion (MCAO), the level of ORM2 is significantly increased in the ischemic penumbra compared with the contralateral normal brain tissue, whereas ORM1 knockout did not affect the infarct size. Exogenous ORM could significantly decrease infarct size and neurological deficit score. Inspiringly, the best administration time point was at 4.5 and 6 hr after MCAO. ORM could markedly decrease the Evans blue extravasation, and improve blood-brain barrier-associated proteins expression in the ischemic penumbra of MACO mice and oxygen-glucose deprivation (OGD)-treated bEnd3 cells. Meanwhile, ORM could significantly alleviate inflammation by inhibiting the production of interleukin 1β (IL-1β), IL-6, and tumor necrosis factor α(TNF-α), reduce oxidative stress by improving the balance ofmalondialdehyde (MDA) and superoxide dismutase (SOD), inhibit apoptosis by decreasing caspase-3 activity in ischemic penumbra of MCAO mice and OGD-treated bEnd.3 cells. Because of its protective role at multiple levels, ORM might be a promising therapeutic target for ischemic stroke.

Morphological analysis of blood vessels near lung tumors using 3-D quantitative CT.

Improved visualization of lung cancer-associated vessels is vital. To evaluate the efficacy of 3-D quantitative CT in lung cancer-associated pulmonary vessel assessment. Vascular CT changes were assessed visually and using FACT-Digital lung TM software (n = 162 patients, 178 controls). The total number of pulmonary vessels (TNV) and mean lumen area of pulmonary vessels (MAV) vertical to cross-sections of fifth/sixth-generation bronchioles were measured. Visual investigation revealed fewer ipsilateral pulmonary vascular abnormalities in lung cancer (151/162) than did quantitative CT (162/162), and required more time (3.2±1.5 vs. 2.5±1.3 min) (P < 0.05). CT measurements revealed that the TNV vertical to the fifth-generation bronchial cross-section of the ipsilateral, contralateral, and control groups was 14.58±4.75, 9.58±3.74, and 10.22±4.07 and the MAV in these groups was 99.70±26.20, 58.76±29.29, and 57.76±18.32, respectively. The TNV vertical to the sixth-generation bronchial cross-section of the ipsilateral, contralateral, and control groups was 16.64±5.14, 11.59±4.06, and 11.75±4.16 and the MAV was 110.22±31.47, 67.62±30.41, and 60.24±16.18, respectively. The TNV and MAV in ipsilateral lung cancer tissues exceeded those in the contralateral side and control group tissues (P < 0.001). Automated 3-D quantitative CT could successfully characterize pulmonary vessels and their lung cancer-associated changes.

Optimization of HDRBT boost dose delivery for patients with rectal cancer

PurposeWe describe methods to improve dose delivery for patients with rectal cancer receiving boost brachytherapy after external beam radiotherapy. Methods and materialsPatients with rectal cancer who were ineligible or refusing surgery are treated with external beam radiotherapy and subsequently with three weekly image-guided volume-adapted high-dose-rate brachytherapy boosts of 10 Gy to the residual clinical target volume, for a total of 30 Gy in three fractions. Tungsten shielding placed at the center of intracavitary mold applicator and double-balloon technique was used to improve dose conformity to the target. ResultsOur results show that the use of tungsten shield and double balloon reduces the dose gradient within the target volume to receive the prescription boost dose of 10 Gy from maximum dose of 60 Gy down to 20 Gy. ConclusionsWe outlined two methods for achieving higher high-dose-rate brachytherapy dose conformity using the tungsten shielding rods (to spare contralateral healthy tissues) and double-balloon technique (to decrease dose gradient within the target to minimize dose to the proximal mucosa).

Prospects for investigating brain oxygenation in acute stroke: Experience with a non-contrast quantitative BOLD based approach.

Metabolic markers of baseline brain oxygenation and tissue perfusion have an important role to play in the early identification of ischaemic tissue in acute stroke. Although well established MRI techniques exist for mapping brain perfusion, quantitative imaging of brain oxygenation is poorly served. Streamlined‐qBOLD (sqBOLD) is a recently developed technique for mapping oxygenation that is well suited to the challenge of investigating acute stroke. In this study a noninvasive serial imaging protocol was implemented, incorporating sqBOLD and arterial spin labelling to map blood oxygenation and perfusion, respectively. The utility of these parameters was investigated using imaging based definitions of tissue outcome (ischaemic core, infarct growth and contralateral tissue). Voxel wise analysis revealed significant differences between all tissue outcomes using pairwise comparisons for the transverse reversible relaxation rate (R 2 ′), deoxygenated blood volume (DBV) and deoxyghaemoglobin concentration ([dHb]; p < 0.01 in all cases). At the patient level (n = 9), a significant difference was observed for [dHb] between ischaemic core and contralateral tissue. Furthermore, serial analysis at the patient level (n = 6) revealed significant changes in R 2 ′ between the presentation and 1 week scans for both ischaemic core (p < 0.01) and infarct growth (p < 0.05). In conclusion, this study presents evidence supporting the potential of sqBOLD for imaging oxygenation in stroke.

Abstract P6-02-02: Near-infrared spectral tomography (NIRST): A prognostic assessment tool for predicting residual cancer burden (RCB) during neoadjuvant chemotherapy (NAC) in breast cancer (BC)

Abstract Background: NIRST, a noninvasive imaging with no ionizing radiation, has been found to be prognostic as a tool to monitor early pathologic response to NAC in BC using biophysical properties of the tumor compared with normal breast tissue. We aim to establish NIRST indicators as early surrogates of treatment response and to evaluate its potential as a predictive tool in treatment decisions. Methods: 27 women with locally advanced BC undergoing NAC were enrolled in this pilot study. NIRST imaging was performed pre-treatment, after cycle 1 and 2, at the mid-point of NAC, and at the conclusion of NAC prior to surgery. Biophysical data including oxy- and deoxy-hemoglobin, water, lipid, and scatter components were obtained at these time points. To minimize inter-subject variability due to breast density and its effects on the NIRST data, statistical analysis was conducted using ratios of obtained biophysical data to pretreatment average of the contralateral normal breast tissue. Residual Cancer Burden (RCB) index was used to evaluate residual disease after treatment with NAC. RCB scores and classes were determined in 24 of the 27 surgical tissue specimens and these were compared to the NIRST data. RCB data for 3 patients were excluded: 2 patients had undergone positive excisional lymph node biopsy prior to NAC and 1 patient had surgery at an outside hospital. Results: Of the 27 patients, 7 had triple negative BC and 13 had HER-2 positive BC. The change in total hemoglobin (ΔHb-T %) after the first cycle of NAC when compared to the pre-treatment total hemoglobin was determined to be the best predicting factor for RCB (p-value &amp;lt;0.001). The Pearson correlation coefficient was calculated for both RBC class and RBC score (0.7 and 0.6). The significance of the correlation coefficient was evaluated using two-sided t-test and the resulting P-values of 0.006 and 0.001 respectively demonstrate that these correlations are statistically significant. Summary of the NIRST biophysical data and the correlating RCBPatientAgeERPRHer2RCB ScoreHbT -ΔHbT-pre136+-+0-139.933.30251---0-43.532.53341+++0-42.281.89430---0-43.061.59552---0-42.541.71663+++0-151.883.12760--+0-46.471.59852---0-42.721.96966--+0-110.022.471039--+0-9.091.101171+-+0-13.331.501252++-4.12153.201.581362++-3.7475.741.531470--+1.931100.521.631553++-3.4447.831.181641+++4.18929.841.511756+++4.44459.001.471850++-4.008-41.112.181954---3.05011.111.802063++-2.90020.001.502149---0.78026.321.902257++-1.8505.881.702347++-3.600-7.692.602470---3.10047.061.70 Conclusions: We have demonstrated a statistically significant correlation between ΔHb-T % after the first cycle of NAC and the RCB. These findings suggest the potential of using NIRST as an early assessment tool to evaluate response to NAC in BC patients and warrant further evaluation in a larger study. Citation Format: Batukbhai B, Jiang S, Bernhardt EB, Muller K, Cao X, Gui J, DiFlorio-Alexander RM, Chamberlin MD, Schwartz GN, Paulsen KD, Pogue BW, Kaufman PA. Near-infrared spectral tomography (NIRST): A prognostic assessment tool for predicting residual cancer burden (RCB) during neoadjuvant chemotherapy (NAC) in breast cancer (BC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-02-02.

Quantitative label-free mass spectrometry using contralateral and adjacent breast tissues reveal differentially expressed proteins and their predicted impacts on pathways and cellular functions in breast cancer

Proteins play an essential role in the biological processes associated with cancer. Their altered expression levels can deregulate critical cellular pathways and interactive networks. In this study, the mass spectrometry-based label-free quantification followed by functional annotation was performed to investigate the most significant deregulated proteins among tissues of primary breast tumor (PT) and axillary metastatic lymph node (LN) and corresponding non-tumor tissues contralateral (NCT) and adjacent (ANT) from patients diagnosed with invasive ductal carcinoma. A total of 462 proteins was observed as differentially expressed (DEPs) among the groups analyzed. A high level of similarity was observed in the proteome profile of both non-tumor breast tissues and DEPs (n = 12) were mainly predicted in the RNA metabolism. The DEPs among the malignant and non-tumor breast tissues [n = 396 (PTxNCT) and n = 410 (LNxNCT)] were related to pathways of the LXR/RXR, NO, eNOS, eIF2 and sirtuins, tumor-related functions, fatty acid metabolism and oxidative stress. Remarkable similarity was observed between both malignant tissues, which the DEPs were related to metastatic capabilities. Altogether, our findings revealed differential proteomic profiles that affected cancer associated and interconnected signaling processes. Validation studies are recommended to demonstrate the potential of individual proteins and/or pathways as biological markers in breast cancer. SignificanceThe proteomic analysis of this study revealed high similarity in the proteomic profile of the contralateral and adjacent non-tumor breast tissues. Significant differences were identified among the proteome of the malignant and non-tumor tissue groups of the same patients, providing relevant insights into the hallmarks, signaling pathways, biological functions, and interactive protein networks that act during tumorigenesis and breast cancer progression. These proteins are suggested as targets of relevant interest to be explored as potential biological markers related to tumor development and metastatic progression in the breast cancer disease.

Early Analysis of Acute Cerebral Infarction by Magnetic Resonance Diffusion Weighted Imaging

Objective: The mortality and disability rate of cerebral infarction are high. Early diagnosis and early treatment can improve the prognosis of patients. Conventional computed tomography (CT) and magnetic resonance imaging (MRI) is lack of sufficient sensitivity. The purpose of this study was to investigate the effect of MRI diffusion weighted imaging (DWI) in the early analysis of acute cerebral infarction. Methods: Forty patients with acute cerebral infarction admitted to the Second Affiliated Hospital of Anhui Medical University were examined in this study. With the cooperation of nursing staff, the routine MRI scan sequence and DWI was performed. The ADC values were analyzed and compared in different patients. Results: All the patients completed the examination successfully. In conventional MRI, equal signal was found in hyperacute cerebral infarction, while high signal on T2WI was found in 66% of patients with acute cerebral infarction. Both hyperacute and acute cerebral infarction showed the high signal in DWI. Compared with the contralateral normal tissues, the ADC value in cerebral infarction area was significantly decreased, especially in patients with hyperacute cerebral infarction. Conclusions: The nursing cooperation is helpful for the MRI examination. The DWI is more sensitive than conventional MRI in the analysis of acute cerebral infarction and can distinguish the hyperacute and acute stage, thus providing evidence for effective individualized treatment of patients.

Involvement of miR-34a and p53 protein of cerebral cortex in electroacpuncture analgesia in mice with neuropathic pain

To explore the involvement of miR-34a in cerebral cortex mediated anti-hyperalgesic effect of electroacupuncture (EA) in mice with neuropathic pain induced by chronic constriction injury (CCI) of sciatic nerve, so as to reveal its mechanisms underlying improvement of neuropathic pain. A total of 75 male C57BL/6 mice were equally randomized into 3 groups: sham, CCI model and CCI+EA (n=25 in each group). Mice of the sham group received simple separation of the right sciatic nerve without ligation. The CCI model was established by liagation of the right sciatic nerve. EA (2 Hz /15 Hz, 1 mA) was applied to bilateral "Zusanli" (ST36) and "Sanyinjiao" (SP9) for 30 min, once every other day. The mechanical and thermal pain threshold of the bilateral hind-paws was detected at the 3rd, 5th and 7th day after modeling, and the expression of miR-34a of bilateral cerebral cortex tissues and that of p53 protein of the left cerebral cortex were determined by using quantitive real time PCR and Western blot, respectively. The mechnical paw withdrawal frequency were significantly higher and the thermal paw withdrawal latencies (PWLs) were significantly shorter at the affected hind-limb (rather than at the healthy hind limb) on day 3, 5 and 7 in the CCI model group than those in the sham group (P<0.05), and considerably reversed at the affected hind-limb (rather than at the healthy hind limb) in the EA group than in the CCI model group (P<0.05), suggesting an analgesic effect of EA intervention. After modeling, the expression levels of miR-34a and p53 on day 3, 5 and 7 were significantly up-regulated in the left cerebral cortex tissue (rather than in the right cerebral cortex) of the CCI model group in comparison with the sham group (P<0.05). After EA intervention, the up-regulated expression levels of miR-34a and p53 in the left cerebral cortex tissue (rather than in the right cerebral cortex) were obviously suppressed in the EA group relevant to the CCI model group (P<0.05). EA stimulation of ST36 and SP9 can down-regulate the expression of miR-34a and p53 in the contra-lateral cerebral cortex tissue of the CCI mice, which may contribute to its anti-hyperalgesic effect.

Mechanical and Microstructural Properties of Native Pediatric Posterior Cruciate and Collateral Ligaments.

Background:Although anterior cruciate ligament (ACL) tears have received the most attention, the medial collateral ligament (MCL) is thought to be the most commonly injured knee ligament overall. The lateral collateral ligament (LCL) and posterior collateral ligament (PCL) are less frequently compromised but can be involved in severe multiligament injuries. The paucity of information on the native properties of these ligaments in the pediatric population hinders the overall optimization of treatment for these injuries.Purpose:To characterize the mechanical and microstructural properties of pediatric MCLs, LCLs, and PCLs using a rare cadaveric cohort (mean age, 9.2 years).Study Design:Descriptive laboratory study.Methods:MCLs, LCLs, and PCLs were harvested from 5 fresh-frozen pediatric knee specimens (3 male, 2 female) and were subjected to a tensile loading protocol. A subset of contralateral tissues from a single donor was analyzed using bright-field, polarized light, and transmission electron microscopy to measure collagen fiber morphology.Results:The pediatric MCL exhibited values for ultimate stress (11.7 ± 6.7 MPa), ultimate strain (18.2% ± 6.8%), and the Young modulus (93.7 ± 56.5 MPa) that were similar to values for the LCL (11.4 ± 11.5 MPa, 27.7% ± 12.9%, and 64.4 ± 76.6 MPa, respectively). The PCL demonstrated decreased ultimate stress (4.2 ± 1.8 MPa), increased ultimate strain (28.8% ± 11.9%), and a decreased Young modulus (19.8 ± 10.4 MPa) when compared with the MCL and LCL. All 3 ligaments had similar mean crimp wavelengths (MCL, 32.8 ± 3.6 µm; LCL, 27.2 ± 3.5 µm; PCL, 25.8 ± 3.5 µm) and collagen fibril diameters (MCL, 88.0 ± 26.0 nm; LCL, 93.3 ± 34.6 nm; PCL, 90.9 ± 34.0 nm); however, the fibril distribution profiles exhibited different modalities.Conclusion:The pediatric MCL and LCL possessed similar mechanical properties, while the pediatric PCL was weaker but capable of withstanding higher amounts of strain. All 3 of these pediatric structures were weaker than what has been reported in studies with adult cohorts.Clinical Relevance:Results from this study can be considered preliminary mechanical and microstructural data for healthy pediatric collateral and posterior cruciate ligaments that can be used to guide further laboratory and clinical research.

Abstract WP550: Pathophysiology of Acute, Subacute and Chronic Lesions in Stroke: A Radiological-Pathological Analysis

Introduction: The imaging characteristics of ischemic lesions seen on MRI aid in the interpretation of the lesion pathogenesis. Early ischemic lesions are seen on diffusion weighted imaging (DWI) with low apparent diffusion coefficient (ADC), later evolve on T2-FLAIR, develop elevated ADC, then disappear on DWI. Chronic white matter lesions (WML) seen on T2-FLAIR but not DWI may or may not be of ischemic origin. Here we present an MRI targeted pathology approach to better describe in-vivo MRI based on cellular changes. Methods: The brain of a patient was obtained for pathological evaluation early after stroke recurrence. As part of clinical care and study procedures, 3T MRI was obtained at baseline (within 2-hours), multiple follow-up visits, and during second admission. Radiological-pathological methods previously validated in trauma was employed. Whole brain 7T MRI was performed after formalin fixation, and MRI targeted pathology was performed, co-localizing three lesions of different ages based on history and presumed imaging characteristics; i) acute, ii) subacute, and iii) chronic vs WML. Homologous contralateral tissue was used as control. Results: Lesions seen in-vivo were observed in post mortem MRI, and reconfirmed in histology. An example of in-vivo and post-mortem MRI, along with corresponding tissue sections and H&amp;E are shown in figure. Qualitative delineation of the boundaries of the chronic lesion on H&amp;E was challenging. A large number of small vessels with enlarged perivascular spaces dominated. The subacute lesion, was characterized by loss of white mater, infiltration of macrophages, and astrocytosis. The acute lesion had a text-book appearance. Conclusion: Dramatic differences are seen in the volume fraction of free water, which likely a major contributor to the appearance on DWI/ADC and T2 FLAIR. Work continues with immunohistochemistry to better delineate the boundaries of the lesions and cellular morphology relevant to in-vivo MRI.

Expression and clinicopathological role of miR146a in thyroid follicular carcinoma.

Dysregulation of microRNA expression has been involved in the development and progression of follicular thyroid carcinoma (FTC). The aim of this work was to study the expression of miRNA146a in FTC and the association with clinicopathological features of the disease. Thirty-eight patients affected by FTC were included in the study. Twenty patients carrying follicular thyroid adenoma (FA) were also enroled as the benign counterpart of FTC. Total RNA including miRNA146a was extracted from formalin-fixed paraffin-embedded (FFPE) pairs of affected/unaffected tissue and its expression was assessed by real-time PCR. Two selected target genes, TRAF6 (tumour necrosis factor receptor-associated factor 6) and IRAK1 (Il-1 receptor-associated kinase 1/2), were also analysed. miR146a expression in FTC tissue was overall not downregulated in malignant versus unaffected tissue, but its expression was inversely correlated with clinicopathological features of FTCs at diagnosis. A decreased expression of miR146a became apparent in FTC thyroid tissue of widely compared to minimally invasive tumours. However, miR146a expression differences between contralateral unaffected tissue (extra-FTC) and FTC were not observed regardless of clinicopathological features. IRAK1, a known target for miR146a, was upregulated in FTC and the increase was mainly appreciable in Hurtle FTC variant. Unexpectedly, miR146a did not correlate with TRAF6 showing an inverse trend compared to IRAK1 although both genes regulate the activity of nuclear factor- kB (NF-kB). The results of this study indicate that downregulation of miR146a, inversely correlated with clinicopathological features of FTCs at diagnosis and suggest a possible involvement of miR146a in FTC development. IRAK1 over-expression in FTC may be related to tumour development/progression. In vitro experiments are needed to support this hypothesis.

Diagnostic value of posttherapy brain single photon emission computed tomography/computed tomography with pentavalent 99mTc dimercaptosuccinic acid in patients with glioblastoma multiform: preliminary report

Aim To evaluate the feasibility of performing 99mTc dimercaptosuccinic acid (DMSA) (V) brain single photon emission computed tomography/computed tomography (SPECT/CT) in patients with glioblastoma multiform after their definitive therapy. Patients and methods Patients with documented grade IV glioma were prospectively recruited for this study. 99mTc-DMSA (V) brain SPECT/CT imaging was acquired after a mean interval of 76 ± 46 days from therapy, 2–3 h. After intravenous injection of 555–740 mBq of the tracer. Scans were interpreted visually as positive or negative by three nuclear medicine physicians. Agreement between two or more physicians was considered a consensus decision. The consensus results of DMSA (V) SPECT/CT were compared against the reference standard which was based on subsequent clinical/neuroimaging follow up or pathology whenever resurgery is performed. Lesion quantitation was performed by one nuclear medicine physician by drawing a region of interest on the lesion site (L) and a mirror region of interest on the contralateral normal brain tissue (NL) then L/NL ratio was calculated. Results A total of 20 patients were enrolled in this study. According to the reference standard, recurrence was detected in 10 patients while 10 were disease free. Interreader kappa agreement ranged from 0.65 to 0.90. Consensus reading of DMSA (V) SPECT/CT correctly detected recurrence in 8/10 (sensitivity 80%) and correctly ruled out disease in 9/10 (specificity 90%). L/NL ratio for positive and negative cases were 6.6 ± 8 and 1.3 ± 1.1, respectively (P Conclusion 99mTc-DMSA (V) brain SPECT/CT is feasible and may be a specific noninvasive diagnostic tool for the follow-up of patients with glioblastoma multiform after chemoradiotherapy.

Mechanical and Microstructural Properties of Pediatric Anterior Cruciate Ligaments and Autograft Tendons Used for Reconstruction.

Background:Over the past several decades, there has been a steady increase in pediatric anterior cruciate ligament (ACL) tears, particularly in young female basketball and soccer players. Because allograft tissue for pediatric ACL reconstruction (ACLR) has shown high rates of failure, autograft tissue may be the best option for ACLR in this population. However, differences in the structure and mechanical behavior of these tissues are not clear.Purpose:To characterize the mechanical and microstructural properties in pediatric ACLs and autograft tissues using a rare cadaveric cohort (mean age, 9.2 years).Study Design:Descriptive laboratory study.Methods:ACLs, patellar tendons, quadriceps tendons, semitendinosus tendons, and iliotibial bands (ITBs) were harvested from 5 fresh-frozen pediatric knee specimens (3 male, 2 female) and subjected to a tensile loading protocol. A subset of contralateral tissues was analyzed using bright-field, polarized light, and transmission electron microscopy.Results:Patellar tendons exhibited values for ultimate stress (5.2 ± 3.1 MPa), ultimate strain (35.3% ± 12.5%), and the Young modulus (27.0 ± 8.8 MPa) that were most similar to the ACLs (5.2 ± 2.2 MPa, 31.4% ± 9.9%, and 23.6 ± 15.5 MPa, respectively). Semitendinosus tendons and ITBs were stronger but less compliant than the quadriceps or patellar tendons. ITBs exhibited crimp wavelengths (27.0 ± 2.9 μm) and collagen fibril diameters (67.5 ± 19.5 nm) that were most similar to the ACLs (24.4 ± 3.2 μm and 65.3 ± 19.9 nm, respectively).Conclusion:The mechanical properties of the patellar tendon were almost identical to those of the ACL. The ITB exhibited increased strength and a similar microstructure to the native ACL. These findings are not entirely congruent with studies examining adult tissues.Clinical Relevance:These results can be used to inform further clinical research. In particular, they justify a further examination of the biomechanical and microstructural properties of the ITB in the context of its role as an autograft tissue in pediatric ACL reconstruction.

Fractal Dimension Analysis of High-Resolution X-Ray Phase Contrast Micro-Tomography Images at Different Threshold Levels in a Mouse Spinal Cord

Fractal analysis is a powerful method for the morphological study of complex systems that is increasingly applied to biomedical images. Spatial resolution and image segmentation are crucial for the discrimination of tissue structures at the multiscale level. In this work, we have applied fractal analysis to high-resolution X-ray phase contrast micro-tomography (XrPCμT) images in both uninjured and injured tissue of a mouse spinal cord. We estimated the fractal dimension (FD) using the box-counting method on tomographic slices segmented at different threshold levels. We observed an increased FD in the ipsilateral injured hemicord compared with the contralateral uninjured tissue, which was almost independent of the chosen threshold. Moreover, we found that images exhibited the highest fractality close to the global histogram threshold level. Finally, we showed that the FD estimate largely depends on the image histogram regardless of tissue appearance. Our results demonstrate that the pre-processing of XrPCμT images is critical to fractal analysis and the estimation of FD.