Tissue Water Research Articles

Free water alterations in different inflammatory subgroups in schizophrenia

BackgroundAccumulating evidence suggests that inflammatory dysregulation both in blood and the brain is implicated in the pathogenesis of schizophrenia. Alterations in peripheral cytokines are not evident in all patients and there may be discrete altered inflammatory subgroups in schizophrenia. Recent studies using a novel and in vivo free-water imaging to detect inflammatory processes, have shown increased free water in white matter in schizophrenia. However, no studies to date have investigated the free water alterations in different inflammatory subgroups in schizophrenia. MethodsForty-four patients with schizophrenia and 49 controls were recruited. The serum levels of interleukin-1 beta (IL-1β), IL-6, IL-10, and IL-12p70 were measured and used for cluster analysis with K-means and hierarchical algorithms. Diffusion tensor imaging (DTI) images were collected for all participants and voxel-wise free water and fractional anisotropy of tissue (FA-t) were compared between groups with Randomise running in FSL. Partial correlation analysis was employed to explore the association of the peripheral cytokine levels with free water. ResultsWe identified two statistically quantifiable discrete subgroups of patients based on the cluster analysis of cytokine measures. The peripheral levels of IL-1β (P < 0.001), IL-10 (P = 0.041), and IL-12p70 (P < 0.001) showed significant differences between the two different inflammatory subgroups. In the inflammatory subgroup with a predominantly higher IL-1β level, increased free water values in white matter were found mainly in the left posterior limb of the internal capsule, posterior corona radiata, and partly in the left sagittal stratum. These affected areas did not overlap with the regions that showed significant free water differences between patients and healthy controls. In the inflammatory subgroup with lower IL-1β levels, peripheral IL-1β was significantly associated with free water values in white matter while no such association was detected in the patient group. ConclusionsLocalized free water differences were demonstrated between the two identified inflammatory subgroups in our data, and free water appears to be a feasible in vivo neuroimaging biomarker guiding the target of inflammatory intervention and development of new therapeutic strategies in an individualized manner in schizophrenia.

Rates of osmoconformation in triploid eastern oysters, and comparison to their diploid half-siblings

Triploid eastern oysters (Crassostrea virginica) suffer greater mortalities than diploids in the U.S. Gulf of Mexico estuaries when extreme low salinities (< 5) and elevated temperatures (≥ 28 °C) coincide. To investigate potential causes, changes in plasma osmolality, hemolymph pH, valve opening and mortality in diploid and triploid oyster half-siblings were compared during a step-down gradual acclimation from a salinity of 5 to 1 (5, 2.5, 2.0, 1.5, 1.0) at 23 °C (expt 1) and at 28 °C (expt 2). To further explore differences in diploid and triploid oyster responses to changing salinity, we compared their plasma osmolality after abrupt decreases in salinity from 20 to 10 and 5, followed by increases in salinity from 5 and 10 to 20 once oysters had osmoconformed to the lowered salinities (expt 3). Lastly, changes in wet weights of mantle tissue explants were compared between diploid and triploid oysters every 10 min for 40 min after being transferred from a salinity of 20 to 10 (expt 4). Oysters of both ploidies were able to osmoconform to water at salinities between 5 and 1.5. After a decrease in salinity, triploid oysters were slower to open their valves and osmoconform, were less efficient in maintaining acid-base status enduring longer periods of acidic hemolymph pH, and were less efficient in regulating tissue water content compared to half-sibling diploid oysters. At a salinity of 1.0, plasma of both diploid and triploid oysters remained hyperosmotic, their hemolymph acidic and their valves closed. Oysters osmoconformed faster at 28 °C than at 23 °C, but the combination of low salinity (≤ 1.5) and higher temperature caused rapid mortalities regardless of ploidies. Triploid oysters, however, started dying earlier and at greater percentages when salinity of 1.5 and temperature of 28 °C were combined. Triploids have been embraced as a means to support higher production, but results indicate superimposed stressors, such as low salinity and high temperature, may be more lethal to triploid than diploid oysters.

Susceptibility of Solanum melongena L/Solanaceae to Drought at Different Growth Stages

The study on the susceptibility of Solanum melongena to drought at different growth stages was conducted in the 2019 and 2020 growing seasons. S. melongena is one of the most relevant agricultural crops in the tropics and subtropical regions of Africa. However, drought has a significant effect on the rate of growth and fruit yield of the crop. However, the growth stage at which S. melongena is vulnerable to the effect of drought needs detailed research and clarification which is the focus of this study. Key morphological traits such as shoot height, number of leaves and branches, and leaf area and water-related physiological indices such as leaf area ratio, net assimilation rate, root shoot ratio, tissue water content including aboveground biomass, leaf relative water content, chlorophyll pigments, osmolytes accumulation, and antioxidants were observed and measured to find the effect of drought at different growth level. The result revealed that the morphological traits, water-related physiological indices, aboveground biomass, leaf relative water content, photosynthetic pigments, antioxidants such as alkaloids and flavonoids of S. melongena were drastically reduced under drought throughout the growth period, associated with vegetative, flowering, and fruiting stage. Osmolytes such as phenol and proline were more enhanced. Across the growth stages, S. melongena subjected to drought at the vegetative stage has exhibited the lowest performance in the measured parameters and has the lowest critical value. S. melongena at the vegetative stage was more vulnerable to drought than the flowering and fruiting stage. Susceptibility to drought of the crop at the vegetative stage can lead to poor growth and yielding.&#x0D;

Conditioned Medium Derived From the Human Amniotic Membrane Prevents Brain Damage Against Cerebral Ischemia/Reperfusion in Subacute, Acute, and Chronic Phases in a Rat Model of Stroke.

Stem cells isolated from the amniotic membrane can produce and release substances that can regenerate damaged tissues and contain proteins and other factors that via numerous major and minor mechanisms lead to increasing angiogenesis and tissue survival. This research was conducted to prove the defensive characteristics of the secretome in the face of temporary focal cerebral ischemia in mouse stroke models. Cerebral ischemia protocol in a specific area was implemented in rats with middle cerebral artery occlusion for 60 minutes and then reperfusion was given for 6, 20, and 30 minutes. Within 30 minutes after the start of reperfusion, conditioned medium derived from the human amniotic membrane (AMSC-CM) was poured into the right ventricle (ICV) at a dose of 0.5 μL. Finally, the volume of the injury, cerebral tissue water, sensorimotor activity, and the strength of the blood-brain barrier integrity were evaluated 24 hours after drug injection. ICV injection of conditioned medium at the start of reperfusion phase considerably decreased the volume of the injury 6, 20, and 30 hours after reperfusion compared to the MCAO-operated group (P<0.01). Cerebral tissue water in the treatment group decreased considerably after the intervention in comparison with the MCAO group in the core and penumbral area not in the subcortical area (P<0.05). Also, the amount of Evans blue infiltration at all times in the core and half-foot area in the AMSC-CM group was significantly reduced in parallel with the MCAO group (P<0.05). Treatment with AMSC-CM during 6-30 h after ischemia-reperfusion insult exerts some beneficial effects against ischemia-reperfusion injury. These findings provide an important vision for more complementary research and treatment of stroke. During ischemia, the brain undergoes a series of harmful pathological events.Mesenchymal stem cells culture medium is called condition medium (CM).CM contains substances that have neuroprotective properties.The use of CM reduces the damage caused by cerebral ischemia. The stem cell culture medium is called condition medium (CM). CM contains substances that have neuroprotective properties. This study aims to investigate the effect of CM on injuries caused by stroke. After causing a stroke in rats by closing the artery, the CM was injected into the injury site. The results showed that CM reduced the severity of the injury.

Evaluation of water quality and bioaccumulation of metals in commercially important fishes: a human health concern.

The present study aimed to determine the physicochemical properties of the coastal water and metal concentration in the muscle tissues of five commercially important fish species (Leiognathus equulus, Lates calcarifer, Sillago sihama, Scolopsis bimaculatus, Lutjanus fulviflamma) along Thondi coast, as well as the potential human health risks on consumption of these species were also studied. Water quality parameters, such as mean temperature (31.3 ± 1.86°C), salinity (28.35 ± 0.79‰), pH (7.95 ± 0.22), TDS (12840 ± 1.49mgL-1), TSS (310 ± 0.51mgL-1) and DO (5.99 ± 0.14mgL-1) were obtained. Various nutrients such as calcium (300.0 ± 36.05mgL-1), inorganic phosphate (0.186 ± 0.02μgL-1), magnesium (1077.6 ± 107.01mgL-1), nitrate (1.584 ± 0.31μgL-1), nitrite (1.179 ± 0.34μgL-1), silicate (29.717 ± 1.93μgL-1) and total phosphorus (0.153 ± 0.08μgL-1) were also analysed. The concentration of metals As, Cd, Cr, Cu, Pb and Zn in the muscle tissue was determined using atomic absorption spectroscopy (AAS). Arsenic, Cu and Pb were found to be highest in S. sihama; 1.2364 ± 0.12, 1.6102 ± 0.28 and 1.0103 ± 0.21μg/g respectively. Cadmium and Zn were found maximum in S. bimaculatus; 0.0876 ± 0.04 and 1.0564 ± 0.16μg/g respectively, whereas Cr was found highest in L. Calcarifer; 1.6781 ± 0.18μg/g. Compared our results with FAO/WHO/EU regulations. The estimated daily intake (EDI) specifies that there is no risk of consuming these species. However, the target hazard quotient (THQ) in As is found to be > 1 in these fish species, which implies a possible danger to consumers.

Test-Retest Reliability of a Protocol for Assessment of Local Tissue Water in the Head and Neck Area.

Background: Lymphedema measurement is vital to select appropriate treatment and monitor its progress. Quantifying lymphedema in the head and neck area is challenging. The use of tissue dielectric constant (TDC) measurements has shown promising results in other body areas. This study aims to determine the test-retest reliability of a TDC measurement protocol developed for the head and neck area. Methods and Results: A detailed measurement protocol, including eight measurement points per side, was developed. Subsequently, the reliability of the protocol was tested in a sample of healthy participants (n = 50, 28 males). Using the LymphScanner (Delfin, Finland), participants were subjected to two measurement sessions. Each measurement point was measured three times per session. Test-retest reliability for each point was evaluated using intraclass correlation coefficients (ICCs) and standard errors of measurement (SEMs). Using the average of three measurements, reliability was good to excellent for all points (ICCs 0.81-0.95), with small measurement errors (SEMs 1.51-2.86). The reliability of a single measurement was moderate to excellent for all measurement points (ICCs 0.58-0.87), with larger, but still small, measurement errors (SEMs 1.65-3.39). When using single measurements, the lowest ICCs were found for the temporal (left 0.73 and right 0.67) and submandibular (left 0.58 and right 0.77) locations. Conclusion: Measurements with the LymphScanner, taken according to the developed protocol, are reliable in healthy participants. We recommend using the average of three measurements to optimize reliability. The protocol is fit for further testing in patient populations and for determining normal values in a larger scale study with healthy subjects.

Bedside Hyperspectral Imaging and Organ Dysfunction Severity in Critically Ill COVID-19 Patients-A Prospective, Monocentric Observational Study.

Hyperspectral imaging (HSI) is a non-invasive technology that provides information on biochemical tissue properties, including skin oxygenation and perfusion quality. Microcirculatory alterations are associated with organ dysfunction in septic COVID-19 patients. This prospective observational study investigated associations between skin HSI and organ dysfunction severity in critically ill COVID-19 patients. During the first seven days in the ICU, palmar HSI measurements were carried out with the TIVITA® tissue system. We report data from 52 critically ill COVID-19 patients, of whom 40 required extracorporeal membrane oxygenation (ECMO). HSI parameters for superficial tissue oxygenation (StO2) and oxygenation and perfusion quality (NPI) were persistently decreased. Hemoglobin tissue content (THI) increased, and tissue water content (TWI) was persistently elevated. Regression analysis showed strong indications for an association of NPI and weaker indications for associations of StO2, THI, and TWI with sequential organ failure assessment (SOFA) scoring. StO2 and NPI demonstrated negative associations with vasopressor support and lactate levels as well as positive associations with arterial oxygen saturation. These results suggest that skin HSI provides clinically relevant information, opening new perspectives for microcirculatory monitoring in critical care.

Multi-model sequential analysis of MRI data for microstructure prediction in heterogeneous tissue

We propose a general method for combining multiple models to predict tissue microstructure, with an exemplar using in vivo diffusion-relaxation MRI data. The proposed method obviates the need to select a single ’optimum’ structure model for data analysis in heterogeneous tissues where the best model varies according to local environment. We break signal interpretation into a three-stage sequence: (1) application of multiple semi-phenomenological models to predict the physical properties of tissue water pools contributing to the observed signal; (2) from each Stage-1 semi-phenomenological model, application of a tissue microstructure model to predict the relative volumes of tissue structure components that make up each water pool; and (3) aggregation of the predictions of tissue structure, with weightings based on model likelihood and fractional volumes of the water pools from Stage-1. The multiple model approach is expected to reduce prediction variance in tissue regions where a complex model is overparameterised, and bias where a model is underparameterised. The separation of signal characterisation (Stage-1) from biological assignment (Stage-2) enables alternative biological interpretations of the observed physical properties of the system, by application of different tissue structure models. The proposed method is exemplified with human prostate diffusion-relaxation MRI data, but has potential application to a wide range of analyses where a single model may not be optimal throughout the sampled domain.

A Mouse Model of MHV-1 Virus Infection for Study of Acute and Long COVID Infection.

COVID-19, caused by SARS-CoV-2, has had a significant global impact. While vaccines and treatments have reduced severe cases and deaths, the long-term effects are not yet well understood. Current models used for research, such as non-human primates and transgenic mice, are expensive and require scarce Biosafety Level-3 (BSL-3) laboratories, thereby limiting their practicality. However, the mouse hepatitis virus 1 (MHV-1) mouse model offers a promising alternative. This surrogate model can be investigated in more widely available Biosafety Level-2 (BSL-2) laboratories. Furthermore, mice are affordable and easy to handle, and utilizing MHV-1 as a surrogate for SARS-CoV-2 eliminates the need for costly transgenic mice. Importantly, the MHV-1 model successfully recapitulates COVID-19-related clinical symptoms, weight loss, multiorgan pathological changes and failure in acute stages, irreversible neurological complications, and other long-term organ dysfunction post-infection, which are similar to available human data post-COVID-19. To assist researchers in establishing and using the MHV-1 mouse model, this protocol offers comprehensive guidance encompassing procedures for animal preparation, induction of viral infection, clinical observation, pathological changes, and tissue analysis for mechanistic studies, thereby yielding valuable insights into disease mechanisms and progression. By adopting the MHV-1 model and the provided protocols, researchers can effectively circumvent financial constraints and the limited availability of BSL-3 laboratories, thus facilitating a more accessible and cost-effective approach to investigating the underlying mechanisms of SARS-CoV-2 pathophysiology and exploring potential therapeutic interventions. © 2023 Wiley Periodicals LLC. Basic Protocol: Induction of mouse hepatitis virus 1 (MHV-1) infection in A/J mice Support Protocol 1: Histological evaluation Support Protocol 2: Liver enzyme measurement Support Protocol 3: Western blot analysis of aquaporin expression Support Protocol 4: mRNA measurement Support Protocol 5: Immunohistochemistry/immunofluorescence Support Protocol 6: Tissue water measurement.

First Report of Colletotrichum fioriniae Infecting Hop (Humulus lupulus) in Michigan.

In July of 2020, a hop (Humulus lupulus L.) grower in Berrien County, Michigan submitted 'Chinook' leaf samples to MSU Plant & Pest Diagnostics. The leaves were covered in small, tan colored lesions, with a small chlorotic halo with an approximate diameter of 5 mm. The grower reported that foliar lesions were in the lower 2 m of the fully developed hop canopy. Disease incidence and severity were estimated at approximately 20% and 5 to 10%, respectively. After incubation at 100% relative humidity, acervuli with orange spore masses and a few setae were present. A pure culture was obtained from these sporulating lesions using water agar. The isolate was hyphal tipped onto potato dextrose agar (PDA) and stored in a glycerol-salt solution at -80o C (isolate CL001) (Miles et al. 2011). On PDA, cultures displayed gray growth on the top of the colony and a red color on the underside of the Petri dish. After 14 days, acervuli with no setae appeared exuding orange conidial masses on the surface of the culture. Conidia were hyaline, aseptate, smooth-walled and rounded at the ends and measured on average 15.89 μm (13.81 to 16.91 μm) × 7.26 (6.82 to 8.41 μm) (n = 20). The color and size of the conidia matched other descriptions of C. acutatum sensu lato (Damm et al. 2012). Four loci (ITS/515 bp - OQ026167, GAPDH/238 bp - OQ230832, CHS1/228 bp -OQ230830, and TUB2/491 bp - OQ230831) were amplified from isolate CL001 (using the primers ITS1/ITS4, GDF1/GDR1, CSH-79f/CHS-354R, and T1/Bt-2b, respectively) and had 100% pairwise identity with C. fioriniae 125396 (JQ948299, JQ948629, JQ948960, JQ949950, respectively, Damm et al. 2012). The GAPDH, CSH1, and TUB2 sequences from isolate CL001 were trimmed, concatenated and aligned with 31 different members of Colletotrichum acutatum sensu lato and C. gloesporioides 356878 (Damm et al. 2012; Kennedy et al. 2022). The alignment was then used to produce a maximum likehood phylogenetic tree using Geneious Prime (Biomatters Ltd.) with the PHYML add on using the HKY + G model (G = 0.34) (Guindon et al. 2010). Isolate CL001 had the closest similarity to C. fioriniae with a bootstrap value of 100. Pathogenicity tests were performed on 2 month-old 'Chinook' hop plants. Twelve plants were inoculated with 50 ml of a conidial suspension (7.95 x 106 conidia/ml) of isolate CL001 (n = 6) or water (n = 6) using a spray bottle until runoff. Inoculated plants were sealed in clear plastic bags and grown in a greenhouse at 21o C with a photoperiod of 14 h. After 7 days, lesions appeared on the hop plants inoculated with CL001, but no symptoms appeared on the water inoculated hop plants. Lesions with a chlorotic halo were observed but they were smaller than field lesions and no setae were present (approx. 1 mm in diam.). Leaves were surface sterilized (0.3% sodium hypochlorite solution for 15 s and then rinsed three times) and the leading margin of the lesions or healthy tissue (water control) were placed on 1% ampicillin amended PDA. Fungal isolates on PDA morphologically matched C. fioriniae were recovered from all CL001-inoculated plants. No C. fioriniae isolates were recovered from the water-inoculated plants. Based on conidial morphology, the four loci, and the phylogenetic tree, isolate CL001 was identified as C. fioriniae. This is the first report of Colletotrichum fioriniae (syn = Glomerella acutata var. fioriniae Marcelino & Gouli) infecting common hop and further investigation is needed to determine if management is needed for this pathogen.

Impact of cannabis use on brain metabolism using 31P and 1H magnetic resonance spectroscopy

PurposeThis prospective cross-sectional study investigated the influence of regular cannabis use on brain metabolism in young cannabis users by using combined proton and phosphorus magnetic resonance spectroscopy.MethodsThe study was performed in 45 young cannabis users aged 18–30, who had been using cannabis on a regular basis over a period of at least 2 years and in 47 age-matched controls. We acquired 31P MRS data in different brain regions at 3T with a double-resonant 1H/31P head coil, anatomic images, and 1H MRS data with a standard 20-channel 1H head coil. Absolute concentration values of proton metabolites were obtained via calibration from tissue water as an internal reference, whereas a standard solution of 75 mmol/l KH2PO4 was used as an external reference for the calibration of phosphorus signals.ResultsWe found an overall but not statistically significant lower concentration level of several proton and phosphorus metabolites in cannabis users compared to non-users. In particular, energy-related phosphates such as adenosine triphosphate (ATP) and inorganic phosphate (Pi) were reduced in all regions under investigation. Phosphocreatine (PCr) showed lowered values mainly in the left basal ganglia and the left frontal white matter.ConclusionThe results suggest that the increased risk of functional brain disorders observed in long-term cannabis users could be caused by an impairment of the energy metabolism of the brain, but this needs to be verified in future studies.

Evaluating the effect of low-density inhomogeneities: A comparative study of lithium fluoride detectors, radiochromic films, and collapsed cone algorithm in 6 MV photon beams

In recent years, there has been significant advancement in the development of physical simulators for dose evaluation. Many dosimetric studies employ solid materials, equivalent to human tissues, to evaluate dose distribution. This study aims to evaluate the effectiveness of inhomogeneity correction carried out by the Monaco/Elekta radiotherapy planning software. To achieve this goal, a physical simulator was created using cork boards to simulate lung tissue and solid water to represent other tissues. This simulator was combined with a dosimetric system that utilized lithium fluoride thermoluminescent detectors - RADOS MTS-N (LiF:Mg,Ti). The thermoluminescent detectors were positioned at various depths using a precisely drilled 2.0 mm thick acrylic plate, and they were placed at predefined positions. The irradiation of the simulator was conducted using an Elekta Synergy® Platform accelerator, employing a 6 MV photon beam with a field size of 15 × 15 cm2 and a source-surface distance (SSD) of 97.5 cm. A radiation dose of 200 cGy was applied for this study. In addition to the dosimetric assessment using thermoluminescent detectors, GAFCHROMIC™ EBT-3 Dosimetry Films were utilized to evaluate the dose at the same measurement points. The dose distribution data measured with the detectors were compared with the values provided by the planning system (TPS) and the inhomogeneity correction was verified. The results support the hypothesis that there is a lack of precision in the analytical simulations performed by the TPS, particularly in cases involving dose distribution at interfaces with varying densities.

Fast high-resolution electric properties tomography using three-dimensional quantitative transient-state imaging-based water fraction estimation.

In this study, we aimed to develop a fast and robust high-resolution technique for clinically feasible electrical properties tomography based on water content maps (wEPT) using Quantitative Transient-state Imaging (QTI), a multiparametric transient state-based method that is similar to MR fingerprinting. Compared with the original wEPT implementation based on standard spin-echo acquisition, QTI provides robust electrical properties quantification towards B1 + inhomogeneities and full quantitative relaxometry data. To validate the proposed approach, 3D QTI data of 12 healthy volunteers were acquired on a 1.5 T scanner. QTI-provided T1 maps were used to compute water content maps of the tissues using an empirical relationship based on literature ex-vivo measurements. Assuming that electrical properties are modulated mainly by tissue water content, the water content maps were used to derive electrical conductivity and relative permittivity maps. The proposed technique was compared with a conventional phase-only Helmholtz EPT (HH-EPT) acquisition both within whole white matter, gray matter, and cerebrospinal fluid masks, and within different white and gray matter subregions. In addition, QTI-based wEPT was retrospectively applied to four multiple sclerosis adolescent and adult patients, compared with conventional contrast-weighted imaging in terms of lesion delineation, and quantitatively assessed by measuring the variation of electrical properties in lesions. Resultsobtained with the proposed approach agreed well with theoretical predictions and previous in vivo findings in both white and gray matter. The reconstructed maps showed greater anatomical detail and lower variability compared with standard phase-only HH-EPT. The technique can potentially improve delineation of pathology when compared with conventional contrast-weighted imaging and was able to detect significant variations in lesions with respect to normal-appearing tissues. In conclusion, QTI can reliably measure conductivity and relative permittivity of brain tissues within a short scan time, opening the way to the study of electric properties in clinical settings.

Maintenance of xylem hydraulic function during winter in the woody bamboo Phyllostachys propinqua McClure.

Frost is a common environmental stress for temperate plants. Xylem embolism occurs in many overwintering plants due to freeze-thaw cycles, so coping with freeze-thaw-induced embolisms is essential for the survival of temperate plants. This study was conducted on Phyllostachys propinqua McClure, a woody bamboo species that was grown under natural frost conditions to explore its responses to winter embolisms. From autumn to the following spring, the following measurements were recorded: predawn branch and leaf embolism, branch and leaf relative water content (RWC), root pressure and soil temperature, xylem sap osmotic potential, branch and leaf electrolyte leakage (EL), branch nonstructural carbohydrate (NSC) content and leaf net photosynthetic rate. P. propinqua had a mean vessel diameter of 68.95 ±1.27 µm but did not suffer severe winter embolism, peaking around 60% in winter (January), with a distinct reduction in March when root pressure returned. Leaves had a more severe winter embolism, up to 90%. Leaf RWC was much lower in winter, and leaf EL was significantly higher than branch EL in all seasons. Root pressure remained until November when soil temperature reached 9°C, then appeared again in March when soil temperatures increased from -6°C (January) to 11°C. Xylem sap osmotic potential decreased from autumn to winter, reaching a minimum in March, and then increasing again. Soluble sugar (SS) concentration increased throughout the winter, peaked in March, and then decreased. These results suggest that (1) there is a hydraulic segmentation between the stem and leaf, which could prevent stem water loss and further embolization in winter; (2) maintenance of root pressure in early winter played an important role in reducing the effect of freeze-thaw cycles on the winter embolism; (3) the physiological process that resulted in a decrease in xylem sap osmotic potential and tissue water content, and an accumulation of SS associated with cold acclimation also aided in reducing the extent of freeze-thaw-induced embolism. All these strategies could be helpful for the maintenance of xylem hydraulic function of this bamboo species during winter.

Determination of the water content of an ex vivo porcine liver

Abstract When modeling High-Frequency (HF) surgical applications the choice of the right dielectric tissue parameters is a key factor for success. The water content of biological tissue is of particular importance since the dielectric tissue properties highly depend on it. Therefore, we investigate a simple and fast method for the determination of relative tissue water content using small samples of an ex vivo porcine liver. To identify the water content, we utilized a desiccation and weighing experiment. It is assumed that the weight loss can be directly attributed to the loss of water in the case of desiccation. Based on the ratio between the initial and dry weight of a sample, the relative water content can be determined. The drying procedure lasted 28 hours, with 16 small samples taken from an ex vivo porcine liver. At the end of the drying procedure, a relative tissue water content of 69.6 % ± 1.1 % was observed. Using a curve fit to the measured data, it can be assumed that approximately 99.3 % of the tissue water content had evaporated by the end of the drying process. With the drying and weighing method used, we were able to determine the water content of the ex vivo porcine liver relatively easily. However, our results also suggest that optimizations of the applied method should be considered for future measurements. Especially, if a faster determination of the water content is required, which in a broader sense should afterward serve for the validation of a simulation model.

Expression and Related Mechanism of miR-744 in Ischemia-reperfusion Rat Model.

To study the expression of miR-744 in the rat model of ischemia-reperfusion (I-R) and its related mechanism. Seventy-five Wistar rats were randomly divided into 3 groups: sham operation group (SOG), model group (MG) and miR-744 group, with 25 in each group. The expression levels of IL-1β, IL-6 and TNF-α were observed by Western Blot after the model preparation, while miR-744 expression was detected by reverse transcription polymerase chain reaction (RT-PCR). The cerebral infarction volume of rats in the MG was significantly larger than that in the miR-744 group (P<0.05). The MG exhibited a markedly higher brain tissue water content than the SOG and the miR-744 group (P<0.05). When compared within the latter two groups, the brain tissue water content in the SOG was significantly lower than that in the miR-744 group (P<0.05). As to miR-744 expression, the relative expression of miR-744 in the brain tissue of the MG was the lowest among the three groups. When compared within the remaining two groups, the miR-744 expression of the miR-744 group was remarkably higher than that of the SOG (P<0.05). In terms of the expression levels of inflammatory factors, the expressions of IL-1β, IL-6 and TNF-α in the brain tissue of the SOG and the miR-744 group were significantly lower than those in the MG, and those of the SOG were significantly lower than that of the miR-744 group. MiR-744 may be involved in the development and progression of I-R in rats, and its mechanism may be related to the regulation of inflammatory response.

A spatial and temporal evaluation of the SMAP cropland b-parameter across the U.S. Corn Belt

The liquid water contained within plant tissue per ground area is an indicator of plant biomass and related to plant transpiration. In the U.S. Corn Belt this plant water is dominated by water in crop tissue. Microwave remote sensing provides an opportunity to measure crop water at a 30 to 40-km spatial scale across the U.S. Corn Belt. Crop water has been shown to be directly proportional to L-band vegetation optical depth (VOD) through a proportionality constant called the b-parameter. NASA’s SMAP satellite uses a static b-parameter of 0.11 for cropland areas, however the b-parameter varies with crop type. This study answers the following research questions. First, does the value of the b-parameter value vary across the U.S. Corn Belt given the observed differences in the proportions of corn and soybeans grown across the region? Secondly, does the SMAP b-parameter value vary throughout the growing season given the significant change in the distribution of crop water within tissue types throughout the growing season? Since in-situ measurements of the b-parameter are higher for corn, we hypothesize that as the relative fraction of corn in a SMAP pixel increases, the b-parameter will increase. We test this hypothesis using satellite scale modeling of crop water and SMAP L2 DCA VOD measurements at 18 sites across the U.S. Corn Belt for the years 2015, 2016, and 2017. For each site year, the crop water for the satellite pixel is simulated using the Agro-IBIS crop model and is weighted according to the proportion of corn and soybeans grown in that location. We find that there is no statistically significant correlation between the relative corn fraction and the SMAP b-parameter across the U.S. Corn Belt and that the current SMAP cropland value of 0.11 is appropriate for the beginning of the growing season (growing degree days(GDD)<100̄0∘C⋅day). However, we find that the b-parameter in the second half of the growing season (GDD≥100̄0∘C⋅day), during the crop reproductive stages, has an average value of 0.17. The results from this study indicate that while there is no change in the b-parameter due to the proportion of crops growing in a satellite pixel, there may be a difference in b-parameter due to changing water distribution within the crop canopy due to the development of crop reproductive structures (ears and pods) during the second half of the growing season.

Balancing growth amidst salt stress - lifestyle perspectives from the extremophyte model Schrenkiella parvula.

Schrenkiella parvula, a leading extremophyte model in Brassicaceae, can grow and complete its lifecycle under multiple environmental stresses, including high salinity. Yet, the key physiological and structural traits underlying its stress-adapted lifestyle are unknown along with trade-offs when surviving salt stress at the expense of growth and reproduction. We aimed to identify the influential adaptive trait responses that lead to stress-resilient and uncompromised growth across developmental stages when treated with salt at levels known to inhibit growth in Arabidopsis and most crops. Its resilient growth was promoted by traits that synergistically allowed primary root growth in seedlings, the expansion of xylem vessels across the root-shoot continuum, and a high capacity to maintain tissue water levels by developing thicker succulent leaves while enabling photosynthesis during salt stress. A successful transition from vegetative to reproductive phase was initiated by salt-induced early flowering, resulting in viable seeds. Self-fertilization in salt-induced early flowering was dependent upon filament elongation in flowers otherwise aborted in the absence of salt during comparable plant ages. The maintenance of leaf water status promoting growth, and early flowering to ensure reproductive success in a changing environment, were among the most influential traits that contributed to the extremophytic lifestyle of S. parvula.

Nutritional Quality and Overall Acceptability Optimization of Ultra-Fast Air-Superchilled Golden Rainbow Trout (Oncorhynchus mykiss, Stevanovski) Using the Response Surface Methodology

Temperatures below the cryoscopic point help to partially freeze most of the water in the fish muscle tissue. This reduces water activity and makes the remaining free water hardly accessible to microorganisms. The objective of this study was to determine the best process regime of ultra-fast air-superchilling, giving us the optimal quality of golden rainbow trout. Two hundred and thirty-four live golden rainbow trout (Oncorchynchus mykiss, Stevanovski) (18 groups of 13 fish in a group) were caught and immediately stunned by an electric current (P = 42 W). The stunned fish was placed in styrofoam cans and covered with flaked ice. The sensory analysis, total nitrogen volatile bases (TVB-N), total number of microorganisms (TVC), and presence of biogenic amines were determined. According to the optimized values for TVB-N, TVC, and sensory scores, giving us a better quality of ultra-fast air-superchilled golden rainbow, the process regime has been found at the following parameters: air temperature T = −11.3 °C; airflow velocity υ = 6.5 m s−1; and packaging layer thickness D = 79.2 μ. The superchilled golden rainbow trout processed by this regime has the lowest degree of proteolytic degradation, delayed development of the microflora, and retains the best possible sensory properties and freshness.

Measuring tissue water potential in marine macroalgae via an updated Chardakov method.

Regulation of tissue water potential is a key mechanism in macroalgal osmotic responses to changing external osmotic conditions, which are common in tidally influenced estuarine and intertidal systems. Nevertheless, significant knowledge gaps exist in our understanding of osmotic responses in macroalgae because few methods measure osmotic potential within macroalgal tissues. Leaf psychrometers have furthered understanding of osmotic potentials in terrestrial plant water relations, yet these have not been developed to measure the range of highly negative potential values found in marine macroalgae. To address these gaps, we present an effective, updated version of the Chardakov method to measure tissue water potential in macroalgae. Here, we present a case study examining macroalgal response in tissue water potential by two morphologically and evolutionarily distinct species, Ulva lactuca (Chlorophyta) and Hypnea musciformis (Rhodophyta) to four paired salinity and nutrient treatments at two temperatures. These treatments simulate a gradient from full coastal ocean conditions to brackish submarine groundwater discharge, an ecosystem type found on basaltic shorelines. Both algae demonstrated plasticity in osmotic response to submarine groundwater discharge with significant positive correlations between tissue water potential and proportion of submarine groundwater discharge in the treatment. These results are the first to describe macroalgal response in tissue water potential, a first step to understanding algal physiological ecology in such complex coastal environments. This revised Chardakov method is a valuable tool to better understand species-specific osmotic responses to ecologically relevant conditions, and can augment the study of other tidal systems and ontogenetic stages.