Hypertonic water reabsorption with a parallel-current system via the glandular and saccular renal tubules of Ruditapes philippinarum.

We investigated the renal function of the brackish water clam, Ruditapes philippinarum, employing magnetic resonance imaging (MRI). The R. philippinarum kidney consists of two renal tubules, a glandular (GT) and a saccular (ST) tubule.

Histology and chronological magnetic resonance images of congenital spinal deformity: An experimental study in mice model.

Background: The natural history of the congenital spinal deformity and its clinical magnitude vary widely in human species. However, we previously reported that the spinal deformities of congenital scoliosis mice did not progress throughout our observational period according to soft X-ray and MRI data. In this study, congenital vertebral and intervertebral malformations in mice were assessed via magnetic resonance (MR) and histological images.

Pulsative venous return from the branchial vessels to the heart of the bivalve Mytilus galloprovincialis supports the constant-volume mechanism.

In bivalves and gastropods, ventricle contraction causes a negative pressure in the auricles and increases venous return from the afferent oblique vein (AOV): the constant-volume (CV) mechanism. The flow in the AOV should be a pulsative flow synchronized with the ventricular contraction. The flow in the heart and adjacent vessels of Mytilus galloprovincialis were measured by magnetic resonance imaging to confirm this hypothesis.

Two synergistic types of muscles were detected during forearm rotation exercise by T cumulative frequency curves using 0.2 T magnetic resonance imaging.

The purpose of this study was the detection and characterization of synergistic muscle activity. Using T-map MRI, T values for 10 forearm muscles in 11 healthy adult volunteers were obtained in the resting state and after isotonic forearm supination and pronation exercises with the elbow extended. T was normalized by Z = (T-T)/SD, where T was T after exercise, while T and SD were the reference values of 34 ms and 3 ms, respectively.

Central administered xenin induced Fos expression in nesfatin-1 neurons in rats.

Xenin is a 25-amino acid peptide identified in human gastric mucosa, which is widely expressed in peripheral and central tissues. It is known that the central or peripheral administration of xenin decreases food intake in rodents. Nesfatin-1/NUCB2 (nesfatin-1) has been identified as an anorexic neuropeptide, it is often found co-localized with many peptides in the central nervous system.

Foot extension and retraction in the clam Calyptogena okutanii without any Keber's valve: an inflatable fastener bag model.

In order to investigate the foot manipulation of a clam without a Keber's valve, Calyptogena okutanii was examined by light microscopy, magnetic resonance imaging and computed tomography. The foot chamber was divided into two compartments by a dense muscle fastener zone (FZ) comprising a pedal artery and sinuses in the mid-sagittal plane in between muscles running in the anterior-posterior oblique direction. The distal part of the foot chamber (inflatable fastener bag, IFB) had a loose superficial muscle layer.

The kidney of the Nodularia freshwater mussel has a larger filtration-size and counter-current system with improved water excretion compared with the seawater mussel Mytilus.

Histological studies and magnetic resonance imaging were employed to analyze the kidney structure and function of the freshwater mussel, Nodularia douglasiae. The Nodularia kidney consists of proximal, intermediate and distal tubules. The epithelia of the renal tubules were composed of a single layer of cuboidal cells.

MRI-based kinematics of the menisci through full knee range of motion.

Purpose: The meniscal kinematics in the full knee range of motion (ROM) have not been demonstrated by MRI, because the narrow bore of the superconducting magnet prevents full knee motion. The purpose of this study was to the investigate meniscal kinematics associated with femorotibial kinematics using an open-structure MRI unit that allows kinematic analysis of the menisci in full knee ROM.

Methods: Non-weight-bearing MR images of the right knee of 10 subjects were acquired at six angles of knee flexion (0°, 30°, 60°, 90°, 120°, and full flexion) using a compact 0.

Microhemorrhage in a Rat Model of Neonatal Shaking Brain Injury: Correlation between MRI and Iron Histochemistry.

Previous studies have shown that neonatal shaking brain injury (SBI) causes transient microhemorrhages (MHs) in the gray matter of the cerebral cortex and hippocampus. Iron deposits and iron-uptake cells are observed surrounding MHs in this SBI model, suggesting local hypoxic-ischemic conditions. However, whether the shaken pups suffered systemic hypoxic-ischemic conditions has remained uncertain.

Detection of muscle activity with forearm pronation exercise using T-map MRI.

[Purpose] We aimed to detect muscle activity during a forearm pronation exercise using a 0.2 T MRI system. [Participants and Methods] We recruited healthy adult volunteers (7 males, 4 females).

Rat mandibular condyle and fossa grew separately then unified as a single joint at 20 days old, which was the weaning age.

Magnetic resonance imaging (MRI) was used to observe growth of the mandibular condyle, mandibular fossa, and articular disc as a single unit. Changes in each component's relative position and size were observed using 7-tesla MRI. Mandibular condyle chondrocytes' growth was evaluated with immunohistochemistry, using the expression of zinc transporter ZIP13.

Size-selective filtration of the atrial wall estimated from the accumulation of tracers in the kidney of the mussel .

In order to determine the molecular weight cut-off (MWCO) for the atrial wall filtration into kidneys of the , we employed five magnetic resonance (MR) tracers: manganese chloride (Mn), gadolinium chloride (Gd), manganese-ethylenediaminetetraacetic acid (MnEDTA), gadolinium-diethylenetriamine pentaacetic acid (GdDTPA) and oligomer-based contrast agent (CH3-DTPA-Gd). After injection of the MR tracers (1 or 2 mmol l×0.1 ml) into the visceral mass, -weighted MR imaging (-MRI) and the longitudinal relaxation rates (1/=) were measured at 20°C.

Roles of Keber's valve and foot chamber for foot manipulation in the mussel .

In order to analyse the roles of Keber's valve for foot manipulation in the mussel , the anatomy and haemolymph flow in the cardiovascular system were detected by magnetic resonance imaging. The superficial layer of the foot was covered by a dense muscle layer, which extended to the dorsal side and connected with the shell. This closed space, the foot chamber, had an inlet (anterior aorta) and an outlet (Keber's valve).

T Distribution in the Forearm Muscles and the T Threshold for Defining Activated Muscle.

Purpose: In order to detect exercised muscles by the increase in T, we have defined a Gaussian T distribution and reference values (T and SD) in resting state muscles, and a threshold for detecting exercised muscles.

Methods: The subjects were healthy adult volunteers (14 males and 12 females). Multiple-spin-echo (MSE) MR images were obtained with 10 TE values from 10 to 100 ms using a 0.

Accumulation and excretion of manganese ion in the kidney of .

-weighted magnetic resonance imaging (-MRI) was employed to detect the accumulation of manganese ion (Mn) in urine in the kidney of the mussel , and the longitudinal relaxation rates (1/=) were measured. When the mussel was exposed to seawater containing 10 µmol l Mn, the -MRI intensity and of the kidney, stomach and digestive glands were increased. Mn might be taken into the hemolymph via the gastrointestinal tract, and then filtrated into the pericardium via the auricles.

Repeated mild shaking of neonates induces transient cerebral microhemorrhages and anxiety-related behavior in adult rats.

Growing evidence suggests that neonatal cerebral microhemorrhages (MHs) are implicated in neuropsychiatric diseases in adults. Although animal studies have identified the progression of the underlying mechanisms of MHs, few studies have investigated the histopathology and behavioral outcomes. In this study, we created an experimental rat model of MHs using a new experimental device for repeated mild shaking brain injury (SBI) in the neonatal period and examined temporal changes in MHs using susceptibility weighted imaging (SWI) and iron histochemistry.

Changes in T-weighted MRI of supinator muscle, pronator teres muscle, and extensor indicis muscle with manual muscle testing.

[Purpose] In order to detect muscle activity with manual muscle testing, T-weighted magnetic resonance (T-MR) images were detected by a 0.2 T compact MRI system. [Subjects and Methods] The subjects were 3 adult males.

A portable infrared photoplethysmograph: heartbeat of Mytilus galloprovincialis analyzed by MRI and application to Bathymodiolus septemdierum.

Infrared photoplethysmogram (IR-PPG) and magnetic resonance image (MRI) of the Mytilus galloprovincialis heart were obtained simultaneously. Heart rate was varied by changing temperature, aerial exposure and hypoxia. Higher heart rates (35-20 beat min) were usually observed at 20°C under the aerobic condition, and typical IR-PPG represented a single peak (peak v).

Involvement of myristoylated alanine-rich C kinase substrate phosphorylation and translocation in cholecystokinin-induced amylase release in rat pancreatic acini.

Cholecystokinin (CCK) is a gastrointestinal hormone that induces exocytotic amylase release in pancreatic acinar cells. The activation of protein kinase C (PKC) is involved in the CCK-induced pancreatic amylase release. Myristoylated alanine-rich C kinase substrate (MARCKS) is a ubiquitously expressed substrate of PKC.

Changes to Muscle T₂after Single-finger Exercise Measured with 0.2T MR Imaging.

We constructed an arm holder for muscle exercise from a forearm-shaped plastic shell and magnetic resonance (MR) imaging position markers and determined the echo time (39 ms) for T₂-weighted spin-echo MR imaging from T₂values of the exercised (50 ms) and resting (32 ms) muscle at 0.2 tesla. The smallest detectable muscle was the extensor digiti minimi muscle (cross-sectional area 25 mm²).

Structure and Size-selective Permeability of the Synovial Membrane of the Temporomandibular Joint of the Mouse Measured by MR Imaging at 7T.

Purpose: We analyzed the anatomical structure of the temporomandibular joint (TMJ) and molecular weight dependency of synovial membrane permeability in mice using 7-tesla magnetic resonance (MR) imaging.

Methods: We obtained 3-dimensional (3D) T1-weighted gradient echo (3D-T1W) and 3D T2-weighted rapid acquisition with relaxation enhancement (3D-T2W RARE) MR images of the TMJ of male C57BL6 mice with voxel resolution of 65 µm. Two-dimensional (2D) T1w images were measured every 45 s before and after bolus intravenous (IV) injection of contrast reagents: gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA; 0.

Magnetic resonance imaging analysis of water flow in the mantle cavity of live Mytilus galloprovincialis.

Water flow inside the shell of Mytilus galloprovincialis was measured by phase-contrast magnetic resonance imaging (MRI). In seawater without algal cells at 23 °C, water approached the mussel from the posterior-ventral side, and entered through the inhalant aperture at a velocity of 40-20 mm s(-1). The flow rate in the lower mantle cavity decreased to 10-20 mm s(-1), the water flowed in the anterior-dorsal direction and approached the demibranches at a velocity of 5-10 mm s(-1).

Testing the constant-volume hypothesis by magnetic resonance imaging of Mytilus galloprovincialis heart.

The constant-volume (CV) hypothesis was tested using the Mytilus galloprovincialis heart under two conditions. The volume of the ventricle, auricles and pericardium, and the flow in the heart and adjacent vessels were measured by magnetic resonance imaging. In synthetic seawater at 23°C (immersed condition), the end-diastolic volume (EDV), end-systolic volume (ESV) and stroke volume (SV) were 50%, 21% and 29% of the heart volume, respectively, and the auricle volume (VA) was maximized at end-systole.

Mn-citrate and Mn-HIDA: intermediate-affinity chelates for manganese-enhanced MRI.

In this study we investigated two manganese chelates in order to improve the image enhancement of manganese-enhanced MRI and decrease the toxicity of free manganese ions. Since both MnCl₂ and a low-affinity chelate were associated with a slow continuous decrease of cardiac functions, we investigated intermediate-affinity chelates: manganese N-(2-hydroxyethyl)iminodiacetic acid (Mn-HIDA) and Mn-citrate. The T₁ relaxivity values for Mn-citrate (4.

Roles of AQP5/AQP5-G103D in carbamylcholine-induced volume decrease and in reduction of the activation energy for water transport by rat parotid acinar cells.

In order to assess the contribution of the water channel aquaporin-5 (AQP5) to water transport by salivary gland acinar cells, we measured the cell volume and activation energy (E (a)) of diffusive water permeability in isolated parotid acinar cells obtained from AQP5-G103D mutant and their wild-type rats. Immunohistochemistry showed that there was no change induced by carbamylcholine (CCh; 1 μM) in the AQP5 detected in the acinar cells in the wild-type rat. Acinar cells from mutant rats, producing low levels of AQP5 in the apical membrane, showed a minimal increase in the AQP5 due to the CCh.