Higher Vv Research Articles

Low b-value Diffusion Tensor Imaging to Analyze the Dynamics of Cerebrospinal Fluid: Resolving Intravoxel Pseudorandom Motion into Ordered and Disordered Motions.

Analysis of cerebrospinal fluid (CSF) dynamics may be beneficial for understanding the mechanisms and diagnosis of several neurological diseases. Low b-value diffusion tensor imaging (low-b DTI) is useful for observing the slow and complex motion of the CSF. Theoretically, a mathematical framework suggests that low-b DTI provides the variance of the pseudorandom motion of the CSF. Furthermore, low-b DTI could provide comprehensive information on fluid dynamics. Accordingly, we proposed an analysis technique that resolves intravoxel pseudorandom motion into ordered (linear) and disordered (random) motions based on the mathematical framework. The proposed analysis technique helps measure low-b DTI with multiple diffusion times and linearly fits its mean diffusivity (MD) with the diffusion time to obtain two parameters, double-slope Vv and y-intersect Dr, which represent the variance of the velocity distribution of linear motion and the diffusion coefficient of random motion, respectively. Seven healthy subjects were scanned to evaluate the proposed technique and investigate fluid dynamics in several representative ROIs. The obtained data showed the validity of the technique, repeatability, and consistency across the subjects in ROIs, such as the lateral ventricle (LV), third ventricle (3V), fourth ventricle (4V), and Sylvian fissure (SF). The obtained parameters Vv and Dr highlighted different characteristics of fluid dynamics in the representative ROIs: low Vv and low Dr in the LV, high Vv and moderate Dr in the 3V, and moderate Vv and moderate Dr in the 4V and SF. The proposed analysis technique will facilitate a comprehensive investigation of the complex dynamics of the CSF using resolved parameters representing ordered and disordered motions.

An Empirical Model of Shape Parameter of Sea Clutter Based on X-Band Island-Based Radar Database

Sea clutter modelling and parameter estimation/prediction are important basis of system design, performance assessment, and target detection of maritime radars. Besides parameter estimation from measured data, parameter prediction from radar parameters, sea state, and the viewing geometry of the radar is an alternative way. In this letter, a dual-polarimetric full-recorded sea clutter database measured by an island-based X-band experimental radar on the Yellow sea of China is introduced. On this database, the model selection reveals that the compound-Gaussian model with inverse Gaussian (CGIG) texture is suited for HH high-resolution sea clutter data, the generalized Pareto (GP) intensity distributions are for HH moderate-resolution data, and the K amplitude distributions are for high and moderate-resolution VV polarized data. Further, three five-parametric empirical formulae are constructed to predict the shape parameter of the CGIG, GP, and K distributions of sea clutter from the area of spatial resolution cell, the grazing angle, the significant wave height, the average wave period, and the wave direction relative to the sight line of radar. The new empirical formulae attain more accurate prediction than existing empirical formula on the database.

398-P: KIM-1 and TNFR 1 and Associations with Early Diabetic Nephropathy Histology

Aim: GFR and urine albumin excretion (UAE) are prevailing measures used to detect and monitor diabetic nephropathy (DN) . We tested whether serum kidney injury molecule-1 (KIM-1) and tumor necrosis factor receptor-1 (TNFR1) , markers of DN progression, are associated with DN renal structural parameters in persons with TIDM. Methods: We measured KIM-1 and TFNR1 in 285 participants from the Renin Angiotensin System Study (RASS) . Participants had T1DM for 2-20 yrs and were free of any clinical DN. Baseline iGFR and kidney biopsies were obtained. We used linear regression to estimate cross-sectional associations of markers with renal structural measures. Results: Mean age was 30 ± yrs; mean iGFR was 125 ± 18 ml/min/1.73 m2; median UAE was 5 (IQR 4- 7) . Higher KIM-1 was associated with significantly greater mesangial fraction volume [Vv (Mes/glom) ] and the tubular atrophy (table 1) . Higher TNFR1 was associated with significantly higher Vv (Mes/glom) and glomerular basement membrane (GBM) width. Neither iGFR nor UAE were significantly associated with lesions. Conclusion: Serum KIM-1 and TNFR1 were associated with higher values for Vv (Mes/glom) , GBM, and tubular atrophy in persons with T1DM and normal kidney function, suggesting relevance as markers of early DN structural changes prior to UAE elevation or GFR decline. KIM-1 is specific to the tubules, highlighting the importance of characterizing the natural history of tubular functions in DN. Disclosure F.Tian: None. D.Prince: None. A.Doria: Research Support; Novo Nordisk Foundation. M.Mauer: None. B.Kestenbaum: Consultant; Reata Pharmaceuticals, Inc. Funding T32

Plasma phospho‐tau181 in over 400 cognitively healthy 69‐ to 71‐year‐olds: Associations with cerebral amyloid, structural imaging and cognition in the Insight 46 study

AbstractBackgroundWe examined cross‐sectional associations between plasma phospho‐tau181 (p‐tau181) and amyloid PET, MRI and cognitive outcomes in Insight 46, a sub‐study of the British 1946 birth cohort.MethodAt age 69‐71, participants underwent blood sampling, neurocognitive assessment, and 3T‐MRI with simultaneous 18F‐florbetapir‐PET (yielding amyloid status binarized at grey matter:eroded white matter SUVR 0.6104). Plasma p‐tau181 was measured by a homebrew Simoa immunoassay. ROC analyses were performed for amyloid status incorporating p‐tau181 into a model combining age, sex and APOE ε4 carrier status (APOE ε4). Linear regression examined associations between p‐tau181 (predictor) and (A): cognitive measures (preclinical AD cognitive composite (PACC), digit‐symbol substitution (DSS), delayed logical memory (LMD), and 12‐item‐face‐name association memory (FNAME‐12)), adjusting for age, sex, APOE ε4, childhood cognition, socioeconomic position and education; and (B): imaging biomarkers of neurodegeneration (whole brain, ventricular and hippocampal volumes (WBV,VV,HV) and AD‐signature cortical thickness (CTh)) and vascular disease (white matter hyperintensity volume (WMHV)), adjusting for age, sex, APOE ε4, amyloid status and total intracranial volume as appropriate.ResultAfter excluding those with prior neurological diagnoses, mild cognitive impairment or dementia, 444 individuals had complete plasma p‐tau181 data (Table 1); 410 had high‐quality amyloid PET data. An amyloid status ROC model using plasma p‐tau181 alone had an AUC of 0.720,95%CI[0.657,0.783]. This was not significantly different from the prediction of a base model incorporating age, sex and APOE ε4 (0.692[0.622,0.761]), but adding plasma p‐tau181 to the base model improved it significantly (0.787[0.737,0.837],2 p<0.001: figure 1). The numbers needed to pre‐screen for a pre‐symptomatic Alzheimer’s trial could be reduced by about 27% by using the latter compared to the base model (table 2). Higher p‐tau181 was associated with lower FNAME‐12 (z‐score‐change for 10% p‐tau181 rise: ‐0.020,95%CI[‐0.033,‐0.007],p=0.003) and lower PACC (‐0.013[‐0.022,‐0.005],p=0.002). Only the latter association was significantly attenuated by further adjustment for amyloid status. Higher p‐tau181 was associated with higher VV (ratio‐change for 10% p‐tau181 rise: 1.010, 95%CI[1.003,1.017],p=0.007) and lower CTh (0.999[0.998,1.000],p=0.007). DSS, LMD, HV, WBV and WMHV had no significant associations with p‐tau181.ConclusionIn cognitively normal individuals, plasma p‐tau181 may contribute toward pre‐screening for amyloid PET positivity, and is associated with cognitive performance and imaging biomarkers of neurodegeneration.

Accelerated Testing of Vanadium Catholyte Stability

There is great interest in redox flow batteriesfor large-scale energy storage1-8. The energy storage capability and power output of a flow battery, unlike conventional batteries, can be scaled independently to suit the desired application.4,8 Other advantages9 include a high degree of safety, long lifetime, potentially low capital costs, high reliability and relatively high energy efficiency. Among the numerous systems that have been studied, the vanadium flow battery (VFB) is commonly regarded as one of the most promising.2,3,10-12 Compared to other flow battery systems, VFBs have the additional advantage that cross-contamination due to transport through the separating membrane is effectively eliminated because the anolyte and catholyte differ only in the oxidation state of the vanadium.13 The thermal stability of the catholyte in the charged condition can be a limiting factor for the performance of VFBs. At the pH of typical VFB catholytes, the solubility of vanadium (V) oxide, V2O5, is ~0.1 mol dm-3 or less14 and so VO2 + is expected to be thermodynamically unstable in solution with respect to precipitation as V2O5. Nevertheless, catholytes with high concentrations of VV (> 1.5 M) in sulphuric acid can persist for very long periods of time.15-20 The stability of these metastable solutions (VFB catholytes) decreases, as expected, as the concentration of VV increases. Stability improves with increasing concentration of sulphate and in the presence of certain additives.2,16-18 We have developed a technique16,19,20 for evaluating the stability of VFB catholytes using a standardised methodology for measuring the induction time for precipitation over a range of temperature. We have quantified the observed variations in terms of concentration coefficients for sulphate and VV and developed a model to predict the stability of VFB catholytes as a function of temperature and composition20.This model is based primarily on data obtained at higher temperatures or with less stable catholytes (i.e., high VV and low sulphate concentration). In this presentation, we extend our range of measurements to much longer times using electrolyte compositions close to those used in practical flow batteries. These results are incorporated into our new, improved model allowing accelerated testing of catholyte stability. 1. A.Z. Weber, M.M. Mench, J.P. Meyers, P.N. Ross, J.T. Gostick, Q. Liu, J. Appl. Electrochem. 41, 1137 (2011)2. M. Skyllas-Kazacos, M.H. Chakrabarti, S.A. Hajimolana, F.S. Mjalli, M. Saleem, J. Electrochem. Soc. 158, R55 (2011)3. M.J. Watt-Smith, P. Ridley, R.G.A. Wills, A.A. Shah, F.C. Walsh, J. Chem. Technol. Biotechnol. 88, 126 (2013)4. S. Roe, C. Menictas, M. Skyllas-Kazacos, J. Electrochem. Soc. 163, A5023 (2016)5. A. Bourke, M.A. Miller, R.P. Lynch, X. Gao, J. Landon, J.S. Wainright, R.F. Savinell, D.N. Buckley, J. Electrochem. Soc. 163, A5097 (2016)6. M.A. Miller, A. Bourke, N. Quill, J.S. Wainright, R.P. Lynch, D.N. Buckley, R.F. Savinell, J. Electrochem. Soc. 163, A2095 (2016)7. Z. Yang, J. Zhang, M. C. W. Kintner-Meyer, X. Lu, D. Choi, J. P. Lemmon and J. Liu, Chem. Rev., 111, 3577 (2011)7. D.N. Buckley, C. O’Dwyer, N. Quill, R.P. Lynch “Electrochemical Energy Storage” Chapter 3 in Energy Storage Options and Their Environmental Impact, ed. R E Hester, R M Harrison, Royal Society of Chemistry, Cambridge (2019)8. D. Reed, E. Thomsen, B. Li, W. Wang, Z. Nie, B. Koeppel, J. Kizewski, V. Sprenkle, J. Electrochem. Soc. 163, A5211 (2016)9. R.M. Darling, A.Z. Weber, M.C. Tucker and M.L. Perry, J. Electrochem. Soc.,163, A5014 (2016)10. A.K. Manohar, K.M. Kim, E. Plichta, M. Hendrickson, S. Rawlings and S.R. Narayanan, J. Electrochem. Soc., 163, A5118 (2016)11. A.M. Pezeshki, R.L. Sacci, G.M. Veith, T.A. Zawodzinski and M.M. Mench, J. Electrochem. Soc., 163, A5202 (2016)12. N. Tokuda, T. Kanno, T. Hara, T. Shigematsu, Y. Tsutsui, A. Ikeuchi, T. Itou and T. Kumamoto, SEI Tech. Rev., 88 (2000)13. T. Silva and T. Ogasawara, Transactions of the Institution of Mining and Metallurgy, Section C, Minerals Processing and Extractive Metallurgy, 102, C188 (1993)14. M. Vijayakumar, Z. Nie, E. Walter, J. Hu, J. Liu, V. Sprenkle and W. Wang, ChemPlusChem, 80, 428 (2015)15. D.N. Buckley, D. Oboroceanu, N. Quill, C. Lenihan, D. Ní Eidhin, S.P. Albu, and R.P. Lynch, J. Electrochem. Society, 165, A3263 (2018)16. D. Oboroceanu, N. Quill, C. Lenihan, R.P. Lynch, and D.N. Buckley, J. Electrochem. Soc., 166, A2270 (2019)17. C. Lenihan, D. Oboroceanu, N. Quill, D. Ní Eidhin, A. Bourke, R.P. Lynch and D.N. Buckley, ECS Trans., 85(13), 175-189 (2018)18. D. Oboroceanu, N. Quill, C. Lenihan, D. Ní Eidhin, S.P. Albu, R.P. Lynch and D. N. Buckley, J. Electrochem. Soc., 163, A2919 (2016)19. D. Oboroceanu, N. Quill, C. Lenihan, D. Ní Eidhin, S.P. Albu, R.P. Lynch and D.N. Buckley, J. Electrochem. Soc., 164, A2101 (2017)

Trail Runners Cannot Reach V˙O2max during a Maximal Incremental Downhill Test.

The purpose of this study was twofold: (i) determine if well-trained athletes can achieve similar peak oxygen uptake (V˙O2peak) in downhill running (DR) versus level running (LR) or uphill running (UR) and (ii) investigate if lower limb extensor muscle strength is related to the velocity at V˙O2peak (vV˙O2peak) in DR, LR, and UR. Eight athletes (V˙O2max = 68 ± 2 mL·min·kg) completed maximal incremental tests in LR, DR (-15% slope), and UR (+15% slope) on a treadmill (+1, +1.5, and +0.5 km·h every 2 min, respectively) while cardiorespiratory responses and spatiotemporal running parameters were continuously measured. They were also tested for maximal voluntary isometric strength of hip and knee extensors and plantar flexors. Oxygen uptake at maximal effort was approximately 16% to 18% lower in DR versus LR and UR (~57 ± 2 mL·min·kg, 68 ± 2 mL·min·kg, and 70 ± 3 mL·min·kg, respectively) despite much greater vV˙O2peak (22.7 ± 0.6 km·h vs 18.7 ± 0.5 km·h and 9.3 ± 0.3 km·h, respectively). At vV˙O2peak, longer stride length and shorter contact time occurred in DR versus LR and UR (+12%, +119%, -38%, and -61%, respectively). Contrary to knee extensor and plantar flexor, hip extensor isometric strength correlated to vV˙O2peak in DR, LR, and UR (r = -0.86 to -0.96, P < 0.05). At similar V˙O2, higher heart rate and ventilation emerged in DR versus LR and UR, associated with a more superficial ventilation pattern. This study demonstrates that well-trained endurance athletes, accustomed to DR, achieved lower V˙O2peak despite higher vV˙O2peak during DR versus LR or UR maximal incremental tests. The specific heart rate and ventilation responses in DR might originate from altered running gait and increased lower-limb musculotendinous mechanical loading, furthering our understanding of the particular physiology of DR, ultimately contributing to optimize trail race running performance.

Abstract 1538: Margetuximab mediates greater Fc-dependent anti-tumor activities than trastuzumab or pertuzumab in vitro

Abstract Margetuximab (M) is an investigational Fc-engineered anti-HER2 monoclonal antibody (mAb) with potential for greater immune-mediated anti-tumor activity than trastuzumab (T). M and T bind the same subdomain IV epitope, but M binds with higher affinity to activating Fc receptor, CD16A (FcγRIIIA), and lower affinity to inhibitory Fc receptor, CD32B (FcγRIIB). Pertuzumab (P) binds to a subdomain II epitope and has the same wild type Fc domain as T. We compared in vitro properties of M, T and P and combinations of M+P and T+P to evaluate Fc domain contributions to anti-HER2 mAb mediated activities. By surface plasmon resonance, M, T and P bound to the HER2 extracellular domain with similar high affinity. Binding affinities of M and T were unchanged if P was pre-bound, indicating lack of interaction. M, T and P exhibited comparable binding to HER2-expressing cell lines. Anti-proliferative activities of M and T toward HER23+ cells (N87, SKBR3 or BT474) in the absence or presence of ligands (EGF or HRG1β) were similar, whereas P exhibited weaker activity. In the absence of ligands, M+P or T+P were comparably as active as M or T alone. In presence of ligands, M+P and T+P were generally more active than M or T alone. Antibody-dependent cell-mediated cytotoxicity (ADCC) was evaluated with N87 and SKBR3 target cells (HER23+, expressing a reporter gene to measure viability) and NK effector cells from donors with differing CD16A158 genotypes. M was 7- to 84-fold more potent than T, as well as 69- to 744-fold more potent than P. Greater differences generally were seen with effector NK cells bearing the more common CD16A158 FF and VF genotypes than with the less common, high affinity CD16A158 VV genotype. While addition of P enhanced mean potency of T by 2- to 3-fold, no such effect was seen with M; however, M or M+P was 7- to 25-fold more potent than T+P. Results with JIMT-1 cells (HER22+) were similar, albeit with lower differential than with HER23+ target cells. NK cells were monitored by flow cytometry following incubation of peripheral blood mononuclear cells with HER2+ target cells and mAbs. M induced greater expression of markers of activation (CD137), cytolytic capability (granzyme B, perforin) and proliferation (Ki67) than T. An anti-HER2 mAb with an inactivated Fc domain was ineffective, indicating that induced changes in NK cells were Fc-dependent. In conclusion, M and T bind HER2 with similar affinity and exhibit comparable anti-proliferative activity that is enhanced by addition of P if ligands (EGF or HRG1β) are present. Relative to T, M mediates superior ADCC with effector cells of all CD16A genotypes and promotes greater NK cell activation and expansion. The M+P combination maintains superior ADCC compared to the T+P combination. Citation Format: Liqin Liu, Yinhua Yang, Robert Burns, Jonathan Li, Haiquan Li, Sergey Gorlatov, Paul Moore, Jeffrey Nordstrom. Margetuximab mediates greater Fc-dependent anti-tumor activities than trastuzumab or pertuzumab in vitro [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1538.

Short time insulin treatment post burn improves elastic-collagen rearrangement and reepithelization

ABSTRACTExtensive burn may cause acute resistance to insulin, which accentuates hypermetabolism, impairs glucose metabolism, immune dysfunction and risks of sepsis. To minimize these effects, insulin is used as a treatment. The purpose was to analyze the collagen-elastic arrangement effects of insulin on the burned skin. Wistar rats were assigned in groups: control (C); control with insulin (C + I); scald burn injury (SBI); and SBI with insulin (SBI+ I). SBI were submitted to 45% total body surface area burn and the insulin-treated groups received insulin (5 UI/Kg/day) for 4 or 14 days (d). Insulin levels, glucose tolerance test and HOMA index were determined. The skin sections were analyzed for histophatological and morphoquantitative data. Histopathological findings showed increased reepithelization of SBI+ I and formation of a new muscle layer after 14 days. In the collagen-elastic arrangement, insulin for 4 days increased the volume fraction (Vv) of thin collagen and elastic fibers. After 14 days, independently of injury, insulin decreased the elastic fibers. Insulin was able to reverse damages in the collagen-elastic rearrangement and stimulate reepithelization after 4 days. Untreated scald-burned animals showed higher Vv of thick collagen after 4 days, while those treated had a higher Vv of thin collagen. The Vv of elastic fibers was increased in SBI+ I for 4 days. In conclusion, insulin treatment was able to stimulate reepithelization. It also reversed the damages to the collagen-elastic arrangement in the scald-burned group, improving the organization of thin collagen and increasing the Vv of elastic fibers in the injured group treated with insulin for a short time, that is, for 4 days.

25.1 OLIGODENDROCYTE PATHOLOGY IN PREFRONTAL WHITE MATTER IN SCHIZOPHRENIA

BackgroundRecent neuroimaging studies have shown altered brain connectivity in patients with schizophrenia, associated with disturbed myelination in different fiber tracts and disruptions of white matter (WM) integrity, including prefrontal WM. We aimed to perform a qualitative and morphometric study of the ultrastructure of oligodendrocytes, myelin-forming cells, in prefrontal WM in schizophrenia and normal controls.MethodsWM of the prefrontal cortex (Brodmann’s area 10) was studied by transmission electron microscopy and morphometry. Size, volume density (Vv) and the number (N) of organelles in oligodendrocytes were estimated in 21 patients with schizophrenia and 20 normal matched controls. Pearson correlation analysis was performed to assess possible correlations between the parameters measured and age, post-mortem interval, neuroleptic treatment and duration of the disease. ANCOVA tests were used for group comparisons.ResultsQualitative study showed swelling, vacuolation, paucity of ribosomes and mitochondria and accumulation of lipofuscin granules in oligodendrocytes in schizophrenia as compared to controls. Morphometry detected lowered Vv and N of mitochondria and higher Vv and N of lipofuscin granules and vacuoles in oligodendrocytes in the schizophrenic group as compared to the control group (all p<0.01).DiscussionAltered metabolism of oligodendrocytes, previously reported reduced number of oligodendrocytes, disrupted myelin/axon integrity, damage and progressive degeneration of myelin sheaths in prefrontal WM in schizophrenia may lead to disturbances in myelination, deficiency of nerve impulses propagation and contribute to network dysfunctions in schizophrenia. Oligodendrocyte and myelin abnormalities may be a target to prevent or restore WM abnormalities and dysfunction of neuronal connectivity in schizophrenia.

Cross-Linked Cholecyst-Derived Extracellular Matrix for Abdominal Wall Repair.

Abdominal wall repair frequently utilizes either nondegradable or biodegradable meshes, which are found to stimulate undesirable biological tissue responses or which possess suboptimal degradation rate. In this study, a biologic mesh prototype made from carbodiimide cross-linked cholecyst-derived extracellular matrix (EDCxCEM) was compared with small intestinal submucosa (Surgisis®), cross-linked bovine pericardium (Peri-Guard®), and polypropylene (Prolene®) meshes in an in vivo rabbit model. The macroscopic appearance and stereological parameters of the meshes were evaluated. Tailoring the degradation of the EDCxCEM mesh prevents untimely degradation, while allowing cellular infiltration and mesh remodeling to take place in a slower but predictable manner. The results suggest that the cross-linked biodegradable cholecyst-derived biologic mesh results in no seroma formation, low adhesion, and moderate stretching of the mesh. In contrast to Surgisis, Peri-Guard, and Prolene meshes, the EDCxCEM mesh showed a statistically significant increase in the volume fraction (Vv) of collagen (from 34% to 52.1%) in the central fibrous tissue region at both day 28 and 56. The statistically high length density (Lv), of blood vessels for the EDCxCEM mesh at 28 days was reflected also by the higher cellular activity (high Vv of fibroblast and moderate Vv of nuclei) indicating remodeling of this region in the vicinity of a slowly degrading EDCxCEM mesh. The lack of mesh area stretching/shrinkage in the EDCxCEM mesh showed that the remodeled tissue was adequate to prevent hernia formation. The stereo-histological assays suggest that the EDCxCEM delayed degradation profile supports host wound healing processes including collagen formation, cellular infiltration, and angiogenesis. The use of cross-linked CEM for abdominal wall repair is promising.

Long-term exposure to ultrasonically nebulized distilled water and saline causes cellular influx and oxidative stress in lung tissue of rats

ABSTRACTPurpose: The aim of this study was to evaluate of the effect of distilled water and saline ultrasonic nebulization on the inflammatory and oxidative stress responses and on the lower airway architecture. Materials and Methods: Twenty-one male Fischer rats were distributed into 3 groups of 7 animals each: a control group (CG), exposed to ambient air; a saline group (SG), exposed to 0.9% sodium chloride (NaCl); and a group exposed to distilled water (DWG). The exposure was carried out in a box attached to an ultrasonic inhaler, occurring for 20 min, 3 times a day for 6 months. At 24h after the last exposure, the animals were euthanized. The bronchoalveolar lavage fluid (BALF) and lungs were collected for study. Results: There was an increase of inflammatory cells in the pulmonary tissue BALF in the DWG compared with the CG. The DWG showed an increase of inflammatory cells compared with the SG and CG. The DWG and SG had higher NADPH oxidase activity than the CG. The volume density (Vv) of the alveolar septum was higher in the DWG than in the SG and CG, and the DWG also had a higher Vv of collagen fibers than the other 2 groups. The DWG presented elevated content of thiobarbituric acid reactive substances in lung homogenates relative to the SG and CG. Conclusions: The ultrasonic nebulization of distilled water increased the influx of inflammatory cells and oxidative damage, and promoted changes in the lung architecture.

Digestibility-related histological attributes of vegetative organs of barrel medic (Medicago truncatula Gaertn.) cultivars

An anatomical analysis of vegetative organs of barrel medic (Medicago truncatula Gaertn.) cultivars was performed using anatomical and stereological methods. The aim was to determine histological bases of the genotypic differences for digestibility, calculate tissue volume densities (Vv), examine the variability and assess tissue proportions along the stem maturity gradient. As the cultivars showed similar proportions of leaf tissues, potential variations in digestibility should be assigned to structural differences observed for the stems. Phloem and xylem Vv increased linearly with stem maturation, whilst Vv of epidermis, mechanical and parenchyma tissue significantly decreased. Secondary xylem was the tissue with the highest potential impact on digestibility. Cultivars ‘Mogul’ and ‘Jemalong’ had low proportion of lignified stem tissues, whilst ‘Parabinga’ and ‘Caliph’ did not show favourable anatomical characteristics. More advantageous proportions of thick-walled and thin-walled cells were recorded in M. truncatula stems, compared to alfalfa (M. sativa). Therefore, examined cultivars are comparable in anatomical quality parameters to this wellknown forage crop. Leaf parameters did not provide variability necessary for the improvement of forage quality. Stem parameters showed higher within-cultivar variability, which could be useful as a starting point in breeding towards improvement of digestibility. As the secondary xylem was the lignified stem tissue with the highest Vv, we recommend the improvement of M. truncatula digestibility through the reduction of its proportion.

Application of a battery of biomarkers in mussel digestive gland to assess long-term effects of the Prestige oil spill in Galicia and Bay of Biscay: Tissue-level biomarkers and histopathology

In order to assess the biological effects of the Prestige oil spill (POS), mussels, Mytilus galloprovincialis, were collected in 22 localities along the North coast of the Iberian Peninsula over 3 years (April 2003-April 2006). Different tissue-level biomarkers including cell type composition (volume density of basophilic cells, Vv(BAS)) in digestive gland epithelium, structural changes of digestive alveoli (mean luminal radius to mean epithelial thickness, MLR/MET) and histopathological alterations (prevalence and intensity) of the digestive gland were analysed. Severe alterations in the general condition of the digestive gland tissue were observed all over the study area up to 2004-2005. High Vv(BAS) values were recorded mainly in Galicia but also to a lesser extent in the Bay of Biscay in 2003-2004. Atrophy of the digestive alveoli, measured in terms of MLR/MET, was detected all along the studied area up to 2006. Inflammatory responses cannot be related to pollution due to the POS: (a) prevalence and intensity of focal hemocytic infiltration were higher in the Bay of Biscay than in Galicia but they did not show a clear temporal trend; (b) high intensities of brown cell aggregates were only sporadically recorded; and (c) granulocytomas were more frequently recorded in the Bay of Biscay than in Galicia and especially in localities (i.e. Arrigunaga) subjected to chronic pollution. Likewise, Marteilia, trematodes, intracellular ciliates, unidentified eosinophilic bodies, R/CLO and Mytilicola did not follow any recognisable pattern that could be associated to the POS. In contrast, high Nematopsis intensities recorded in several localities in 2003 might suggest some response of local interest after the POS (i.e., in combination with particular factors/conditions). More data at a regional scale are needed before histopathology may provide a reliable ecosystem health assessment but the present results suggest that the approach is worthwhile. Overall, although Vv(BAS) returned to reference values by 2004-2005, MLR/MET values indicated that the mussel health condition was affected during the whole study period up to April 2006.

Application of a battery of biomarkers in mussel digestive gland to assess long-term effects of the Prestige oil spill in Galicia and Bay of Biscay: Correlation and multivariate analysis

According to published reports, selected cell and tissue-level biomarkers revealed alterations in the health status of mussels collected after the Prestige oil spill (POS) in Galicia and the Bay of Biscay (2003-2006). Presently, univariate and multivariate analysis provides a comprehensive view of the whole data set. Correlation and principal component analysis (PCA) were performed using biomarkers corresponding to or derived from those data, say: induction, AOX(exp), and inhibition, AOX(eff), of Acyl-CoA oxidase enzyme activity; membrane labilisation period, LP, volume density, Vv(LYS), and surface-to-volume ratio, S/V(LYS), of digestive cell lysosomes; volume density of neutral lipids, Vv(NL); volume density of basophilic cells, Vv(BAS), mean luminal radius to mean epithelial thickness in digestive gland epithelium, MLR/MET; gonad index, GI; cumulative intensity of inflammatory responses, CI(IR) and parasitic infestation, CI(PI). The PCA results were used to classify sampling times and localities by means of hierarchical cluster analysis. Biomarkers were more frequently correlated with naphthalene than with total PAH concentration in mussel tissues. Many biological parameters were correlated with each other in agreement with their involvement in toxic processes or their role in the mussels' response against environmental insult. Naphthalene appears to be the most effective toxic herein, which supports that the reported effects may be mainly due to POS. According to the PCA, 4 groups of biomarkers explained 67.37% variability and the factors that most strongly contributed were S/V(LYS), CI(IR), Vv(BAS) and MLR/MET. These factors were used in the hierarchical cluster analyses carried out. The cluster analysis performed to classify sampling times discriminated 3 significantly different periods after POS: (a) a high affection period (until April-04); (b) the beginning of the recovery; and (c) an advanced recovery status in which geographical variability increased (from April-05 onwards). As regards the clustering of localities, major geographical differences were not detected but three outliers were identified: (a) early and highly impacted localities in Galicia and Bay of Biscay; (b) Aguiño that was characterised by extremely high Vv(BAS) during 2003; and (c) localities that were subjected to persistent chronic pollution.

Ultrastructural abnormalities of astrocytes in the hippocampus in schizophrenia and duration of illness: A postortem morphometric study

There is a lot of evidence of astrocytic dysfunction in schizophrenia. We performed an electron microscopic morphometric study of astrocytes in the CA3 hippocampal region in 19 cases of schizophrenia and 16 normal controls. No significant group differences were found in cell size, volume fraction (Vv) and area density (Na) of mitochondria and lipofuscin granules. Young control subjects (<50 years old) had significantly lower area of cell, nucleus and cytoplasm and higher Vv and Na of mitochondria than old controls (>50 years old), and young and old schizophrenic cases. No significant differences between young and old schizophrenic subgroups were found. Vv and Na of mitochondria correlated negatively (r=−0.66, r=−0.72, P<0.01) and Vv of lipofuscin granules correlated positively (r=0.72, P=0.001) with duration of illness. These parameters did not correlate with age in controls and in schizophrenic subjects. Both Vv and Na of mitochondria were significantly lower in the subgroup of cases with duration of disease of>21 years. than in the control group and in the subgroup of cases with duration of illness of<21 years (P<0.01). The data suggest progressive disturbances of astrocyte function due to the deficit of mitochondria in schizophrenia.

Ultrastructural abnormalities of astrocytes in the hippocampus in schizophrenia and duration of illness: A postortem morphometric study

There is a lot of evidence of astrocytic dysfunction in schizophrenia. We performed an electron microscopic morphometric study of astrocytes in the CA3 hippocampal region in 19 cases of schizophrenia and 16 normal controls. No significant group differences were found in cell size, volume fraction (Vv) and area density (Na) of mitochondria and lipofuscin granules. Young control subjects (<50 years old) had significantly lower area of cell, nucleus and cytoplasm and higher Vv and Na of mitochondria than old controls (>50 years old), and young and old schizophrenic cases. No significant differences between young and old schizophrenic subgroups were found. Vv and Na of mitochondria correlated negatively (r=-0.66, r=-0.72, P<0.01) and Vv of lipofuscin granules correlated positively (r=0.72, P=0.001) with duration of illness. These parameters did not correlate with age in controls and in schizophrenic subjects. Both Vv and Na of mitochondria were significantly lower in the subgroup of cases with duration of disease of>21 years. than in the control group and in the subgroup of cases with duration of illness of<21 years (P<0.01). The data suggest progressive disturbances of astrocyte function due to the deficit of mitochondria in schizophrenia.

Thermal plasticity of mitochondria: A latitudinal comparison between Southern Ocean molluscs

Mitochondrial volume density (Vv (mt,f)), cristae surface density (Sv (im,mt)), cristae surface area (Sv (im,f)) and citrate synthase (CS) activity were analysed as indicators of thermal acclimation in foot muscle of the limpet, Nacella concinna, and the clam, Laternula elliptica, collected from 4 locations within the Southern Ocean, South Georgia (54°S, N. concinna only), Signy (60°S), Jubany ( L. elliptica only − 62°S) and Rothera (67°S). Animals were acclimated to 0.0 °C whilst a sub-set of N. concinna (South Georgia, Signy and Rothera) and L. elliptica (Rothera) were acclimated to 3.0 °C. At 0.0 °C N. concinna had higher Vv (mt,f), Sv (im,mt), Sv (im,f) and muscle fibre specific CS activity than L. elliptica which correlated with the more active life style of N. concinna. However, mitochondrial density was very low, 1–2% in both species, suggesting that low temperature compensation of mitochondrial density is not a universal evolutionary response of Antarctic marine ectotherms. Both Sv (im,mt) and Sv (im,f) were reduced by warm acclimation of N. concinna. South Georgia N. concinna maintained muscle fibre specific CS activity after acclimation, in contrast to N. concinna from Rothera and Signy and L. elliptica from Rothera, indicating that they have the physiological plasticity to respond to their warmer, more variable thermal environment.

Comparison of cytochemical procedures to estimate lysosomal biomarkers in mussel digestive cells

Enlargement and membrane destabilisation in digestive cell lysosomes of mussels are biomarkers of pollution effect. Cytochemical methods are currently applied to determine lysosomal membrane stability (LMS) and lysosomal structural changes (LSC). LMS, determined after grading N-acetyl-β-hexosaminidase activity on cryotome sections of digestive gland, is measured as labilisation period (LP). LSC, determined after image analysis of cryotome sections where β-glucuronidase activity is revealed, are measured as lysosomal volume (Vv), surface (Sv), numerical (Nv) densities and surface-to-volume ratio (S/V). Both methods have now been compared in a field study. Mussels were collected from Biscay Bay (Plentzia, reference; Muskiz, moderately polluted) and North Aegean Sea (Olympiada, reference; Limani, heavily polluted). Higher Vv and Sv and lower S/V and LP were recorded in polluted sites than in reference sites. Significant correlations with LP were found for Vv and S/V. The cost/effectiveness and environmental significance of both methods are discussed.

Adaptations to diving hypoxia in the heart, kidneys and splanchnic organs of harbor seals (Phoca vitulina)

Pinnipeds (seals and sea lions) have an elevated mitochondrial volume density [VV(mt)] and elevated citrate synthase (CS) and beta-hydroxyacyl-CoA dehydrogenase (HOAD) activities in their swimming muscles to maintain an aerobic, fat-based metabolism during diving. The goal of this study was to determine whether the heart, kidneys and splanchnic organs have an elevated VV(mt) and CS and HOAD activities as parallel adaptations for sustaining aerobic metabolism and normal function during hypoxia in harbor seals (Phoca vitulina). Samples of heart, liver, kidney, stomach and small intestine were taken from 10 freshly killed harbor seals and fixed in glutaraldehyde for transmission electron microscopy or frozen in liquid nitrogen for enzymatic analysis. Samples from dogs and rats were used for comparison. Within the harbor seal, the liver and stomach had the highest VV(mt). The liver also had the highest CS activity. The kidneys and heart had the highest HOAD activities, and the liver and heart had the highest lactate dehydrogenase (LDH) activities. Mitochondrial volume densities scaled to tissue-specific resting metabolic rate [VV(mt)/RMR] in the heart, liver, kidneys, stomach and small intestine of harbor seals were elevated (range 1.2-6.6x) when compared with those in the dog and/or rat. In addition, HOAD activity scaled to tissue-specific RMR in the heart and liver of harbor seals was elevated compared with that in the dog and rat (3.2x and 6.2x in the heart and 8.5x and 5.5x in the liver, respectively). These data suggest that organs such as the liver, kidneys and stomach possess a heightened ability for aerobic, fat-based metabolism during hypoxia associated with routine diving. However, a heightened LDH activity in the heart and liver indicates an adaptation for the anaerobic production of ATP on dives that exceed the animal's aerobic dive limit. Hence, the heart, liver, kidneys and gastrointestinal organs of harbor seals exhibit adaptations that promote an aerobic, fat-based metabolism under hypoxic conditions but can provide ATP anaerobically if required.

The angiotensin-converting enzyme DD genotype is associated with glomerulopathy lesions in type 2 diabetes.

Genetic factors are important in conferring diabetic nephropathy (DN) risk. The insertion/deletion (I/D) polymorphism of the ACE gene has been described to be associated with DN risk and progression. The renal lesions underlying DN in type 2 diabetes are heterogeneous; only a subset of patients, characterized by a faster decline of renal function, have diabetic glomerulopathy. This study explored the relations between diabetic glomerulopathy and the ACE genotype distribution in 77 type 2 diabetic patients with an albumin excretion rate > or = 20 microg/min. Using morphometric analysis of kidney biopsies, mesangial and mesangial matrix fractional volumes [Vv(mes/glom) and Vv(MM/glom)] and glomerular basement membrane (GBM) width were estimated. We found that 13 patients were II, 30 were ID, and 34 were DD. Clinical features and renal function were similar in the three groups; in contrast, the DD patients had the highest Vv(MM/glom) and GBM width. Subdividing patients in tertiles of GBM width and Vv(MM/glom), from the lowest (I) to the highest (III) values, the DD carriers had an odds ratio of 6.11 (95% CI 1.84-20.3) and 10.67 (2.51-45.36), respectively, for the likelihood of being in tertile III than I for GBM width and Vv(MM/glom). Multiple regression analysis revealed the I/D polymorphism as an independent determinant of GBM thickening in addition to diabetes duration and HbA(1c). In conclusion, the ACE DD genotype is associated with diabetic glomerulopathy lesions, making the study of this polymorphism helpful in identifying those type 2 diabetic patients at higher risk of fast DN progression.