State Of Water In Tissue Research Articles

Computer assisted rapid nondestructive method for evaluation of meat freshness

In this study a technique was developed to predict the meat freshness decay by employing a nondestructive visible imaging method and a computer assisted analysis. The technique uses Opto-magnetic imaging spectroscopy and machine learning algorithms for detecting of freshness during storage. The opto-magnetic spectra of meat samples were acquired at 0, 12 and 24 hours of refrigerated storage using specially developed imaging system and computer image processing algorithm. The obtained spectra were related to the storage time of the samples, and several machine learning classification algorithms were tested. The best prediction results of freshness for chicken and beef was achieved using lazy IB1 classifier with the accuracy of 97.47% for chicken, and 98.23% for beef. Since the method is concerned with detecting changes in the state of water in tissues, the freshness decay period was estimated based on changes in meat hydration properties.

Non-Invasive Measurement of Pathological Heterogeneity of Cancer Tissues Using Water State Information from Diffuse Optical Spectroscopic Imaging.

Abstract Background: In our previous work, we have shown that biochemical tissue water state correlates with histopathological scores of breast cancer (R=-0.96). Based on the result, we extended our research to test whether the tissue water measurement can differentiate heterogeneous pathological structures of cancer tissues of different grades. Diffuse Optical Spectroscopic Imaging (DOSI) measures water molecular vibrational states associated with macro-molecular complexes in tissues such as proteins in a non-invasive way without compression of the breast. For DOSI measurements, a large region over breast tumors is scanned using a hand-held probe and spectral information on each point is spatially mapped to generate an image.Subjects and Methods: DOSI was employed to measure 19 primary cancers (18 IDC and 1 ILC). The spectral features of tissue water absorption from 935 nm to 998nm were compared to those of a pure water spectrum measured at body temperature in order to acquire the Bound Water Index (BWI: the residual between tissue and pure water spectra). In the spectroscopic images, the average and standard deviation of the pixels less than 20% of the range of the BWI in the image were calculated based on our previous finding that carcinoma tissues have lower BWI (more free water). The same parameters were calculated on normal tissues from the same patients in order to compare the tissue heterogeneity. The standard deviation was divided by the average value of each tissue type, and this value is communicated as a Heterogeneity Index (HI).Results: In our in vivo clinical studies, the cancer tissues showed 51% higher heterogeneity than the normal tissues (cancer HI: 0.046±0.018, normal HI: 0.024±0.018, p<0.001). Furthermore, the low (N=4), medium (N=9) and high grade (N=6) tumors, defined by the Nottingham Bloom-Richardson histopathological scores (3-5: low, 6-7: med and 8-9: high), demonstrated increasing heterogeneity in the water disposition with the tumor grade. The medium and high grade tumors had 10.5 and 28% more heterogeneity than the low grade tumors in average (low grade HI: 0.041±0.015, med: 0.045±0.02 and high: 0.052±0.017).Discussion: The tissue water measurement using DOSI showed its ability to measure increased pathological heterogeneity in more invasive cancer tissues. This result supports our earlier finding that the BWI can report on histopathological grades of cancer tissues. These pathological properties were acquired in a completely non-invasive way with non-ionizing low power light. The results of this study suggest that the water state measurement using DOSI may be used as a non-invasive optical biopsy with high specificity. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5008.

Non-invasive detection and monitoring of tumor pathological grade during neoadjuvant chemotherapy by measuring tissue water state using diffuse optical spectroscopic imaging.

Abstract Abstract #803 Background: Changes of tissue water state are related to physiological and pathological properties of breast tissues. For instance, MRI has measured water mobility in order to monitor local micro-structural changes in breast cancer tissues during chemotherapy. Diffuse Optical Spectroscopic Imaging (DOSI) measures water molecular vibrational states associated with macro-molecular complexes in tissues such as proteins. For DOSI measurements, breast tumors are line-scanned and spectral information on each point is spatially mapped to generate an image.
 Subjects & Methods: DOSI was employed to measure 15 infiltrating ductal carcinoma (IDC) patients before treatment. Five IDC and one infiltrating lobular carcinoma (ILC) tumors were also measured along the course of neoadjuvant chemotherapy. Patient responses were determined from standard pathology: complete (N=2), partial (N=2) and non-responders (N=2). The spectral features of tissue water absorption from 935 nm to 998nm were compared to those of a pure water spectrum measured at body temperature in order to acquire the Bound Water Index (BWI: the residual between tissue and pure water spectra). In spectroscopic images, the Cancer BWI Ratio (CBR) was calculated by counting the fraction of the BWI less than 20% of the BWI range of pre-chemo (baseline) measurement in a primary cancer. Lower BWI means the cancer has more free water. The CBR communicates the changes of tissue water state along the course of therapies in the similar way to Signal Enhanced Ratio (SER) used in contrast enhanced MRI.
 Results: In our in vivo clinical studies with 15 IDC tumors, a high inverse correlation between BWI and Nottingham Bloom-Richardson histopathological score (R=-0.87) was found. In the neoadjuvant chemotherapy studies, BWI increased during the entire course of the therapy in complete responders while it fluctuated then stayed close to baseline values in partial responders. In non-responders, the change amount of BWI was very small and the BWI values decreased below baseline values. Quantitatively, for complete responders, BWI increased (more bound water) 59% from baseline and CBR decreased (less pixels for cancer) 26.9% and the pixels presenting cancer property disappeared. In partial responders, BWI increased 4.7% and CBR decreased 8.2% whereas, in non-responders, BWI decreased 16.4% and CBR increased 28.7%.
 Discussion: The high correlation between BWI and histopathological score communicates that water state measurements using DOSI report on disease grades of breast cancer non-invasively. In the neoadjuvant chemotherapy studies, bigger tissue water state changes have been measured in complete than partial responders and the changes to the opposite direction in non-responders. There results demonstrate a potential of tissue water state with DOSI as a non-invasive pathological grade monitor during chemotherapy, which can be used as a substitute for a biopsy at any point during the treatment cycle. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 803.

Energy metabolism and cerebral blood flow during cytotoxic brain edema induced by 6-aminonicotinamide.

We investigated the progression of cytotoxic brain edema induced by 6-aminonicotinamide (6-ANA), a potent antimetabolite of nicotinamide, by measuring the time courses of changes in brain tissue water state (with MRI), histology (with H&E staining), energy metabolism (with 31P-NMR), brain hemoglobin concentration (with near-infrared spectroscopy; NIRS), cerebral blood flow and volume (CBF. CBV), mean arterial blood pressure (MABP), and brain activity (with EEG) up to 10 hours (h). Change in cerebrovascular autoregulation was also investigated. 6-ANA (120 mg/kg) was administered intraperitoneally to 30 male Wistar rats (250-350 g). After 10 h, the T2-weighted signal intensity was increased (p < 0.05), and H&E staining showed severe vacuolation of glial cells. ATP production/consumption and intracellular pH were well maintained up to 10 h, while the intensity of the phosphomonoesters (PME) signal was significantly increased (p < 0.05). Oxygen consumption gradually decreased from 4 to 10 h. CBF and MABP were all significantly increased (by 2.5-fold for CBF) (p < 0.05). Theta and delta wave amplitudes were reduced at 10 h. In summary, 6-ANA (120 mg/kg) induced cytotoxic brain edema from 4 to 10 h. Energy balance and brain activity were well maintained up to 10 h, though cerebrovascular autoregulation was impaired.

SNR gains with superconducting coils and hyperpolarized inert gas

Magnetic resonance microscopy (MRM) has advanced from a technical challenge to a practical tool in a wide range of basic sciences (1). The nondestructive nature of the technique allows for repeated studies of the same sample, retrospective studies through any arbitrary plane, registered studies using different contrast mechanisms, and examination of valuable specimens. "Proton contrast" is provided by making use of T1, T2, T1ρ , diffusion, and magnetization contrast weightings, thus permitting direct examination of the state of water in tissues; something not possible with other microscopic techniques. The technical hurdles imposed by a limited signal-to-noise ratio (SNR) have been partially overcome by improved RF coil design and by three dimensional Fourier transform encoding for large arrays. We have introduced two additional technologies that help to further redress this SNR deficit: superconducting RF coils and inert gas hyperpolarization.It has been argued elsewhere (2,3) that the dominant source of noise in the receiving chain for small objects in high fields is the pickup coil and the preamplifier.

Nuclear Magnetic Resonance Imaging of Grape Buds during the Photoperiodic Induction of Dormancy

Changes in water status have been associated with various stages of dormancy and freezing tolerance in woody perennials. Recent studies in apple indicate that changes in the state (bound vs. free) of bud water are strongly correlated with the end of dormancy. In this study nuclear magnetic resonance imaging (NMRI) was used to monitor changes in the state of bud water during the photoperiodic induction of endo-dormancy in Vitis riparia. Bud water status was monitored using proton relaxation times from T1 and T2 images determined at 2, 4, and 6 weeks of long (LD) or short (SD) photoperiod treatments. Bud dormancy was determined by monitoring budbreak in plants defoliated after photoperiod treatments. NMRI allowed nondestructive monitoring of changes in tissue water state. T1 and T2 maps indicated changes in the state of the water in bud and stem tissues during the 6 weeks of treatment. Differences in relaxation times for nondormant and dormancy-induced (reversible) buds were not clear. However, T2 relaxation times were lower in the dormant buds than in the nondormant buds.