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This study aimed to investigate the effect of surgery on the gamma loop of the quadriceps on the side with an intact knee in patients with anterior cruciate ligament (ACL) injuries. We compared longitudinally the response of alpha motor neurons to vibration stimulation of the quadriceps on the side with an intact knee before and after ACL reconstruction. To evaluate alpha motor neuron response, we measured the maximal knee extension strength and integrated electromyography of the vastus medialis, vastus lateralis, and rectus femoris. After obtaining pre‐vibration data from each subject, vibration stimulation was applied to the infrapatellar tendon, and the same measurements were performed immediately after stimulation. The results of this study showed that the response to prolonged vibration stimulation on the intact side of the quadriceps did not differ pre‐ and post‐surgery. As vibration stimuli normally elicit a decrease in alpha motor neuron activity in normal individuals, abnormal responses to prolonged vibration stimulation of the quadriceps on the side with an intact knee might be observed in patients with ACL injuries. The abnormality of the gamma loop of the quadriceps on the side with an intact knee was probably induced by the rupture. Based on these results, we conclude that surgery does not induce further gamma loop abnormalities on the intact side of the quadriceps. [ABSTRACT FROM AUTHOR]

Foodborne disease outbreaks caused by raw olive flounders ( Paralichthys olivaceus) parasitized with Kudoa septempunctata have been reported in Japan. Origins of olive flounders consumed in Japan vary, being either domestic or imported, and aquaculture-raised or natural. Although it is unknown whether different sources are associated with different outcomes, it is desirable to identify whether this is the case by determining whether unique K. septempunctata strains occur and if so, whether some are associated with foodborne illness. We here developed an intraspecific genotyping method, using the sequence variation of mitochondrial genes. We collected olive flounder samples from foodborne disease outbreaks, domestic fish farms or quarantine offices and investigated whether K. septempunctata genotype is associated with pathogenicity or geographic origin. The 104 samples were classified into three genotypes, ST1, ST2 and ST3. Frequency of symptomatic cases differed by genotypes, but the association was not statistically significant. Whereas K. septempunctata detected from aquaculture-raised and natural fish from Japan were either ST1 or ST2, those from fish inspected at quarantine from Korea to Japan were ST3. Our method can be applied to phylogeographic analysis of K. septempunctata and contribute to containing the foodborne disease. The genotype database is hosted in the Pub MLST website (). [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the toxicokinetic characteristics of melamine in broilers due to the limited information available for livestock. Melamine was then administered to broiler chickens at an intravenous (i.v.) or oral (p.o.) dosage of 5.5 mg/kg of body weight, and plasma samples were collected up to 48 h. The concentration of melamine in each plasma sample was analyzed using liquid chromatography-tandem mass spectrometry ( LC- MS/ MS). Melamine was measurable up to 24 h after i.v. and p.o. administration. A one-compartment model was developed to describe the toxicokinetics of melamine in broilers. Following i.v. administration, the values for the elimination half-life (t1/2 β), the volume of distribution (Vd), and the clearance ( CL) were 4.42 ± 1.02 h, 00.52 ± 0.18 L/kg, and 0.08 ± 0.01 L/h/kg, respectively. The absolute oral bioavailability (F) was 95.63 ± 3.54%. The results suggest that most of the administered melamine is favorably absorbed from the alimentary tract and rapidly cleared by the kidneys in broiler chickens. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate motor unit recruitment in the quadriceps femoris (QF) after anterior cruciate ligament (ACL) rupture and repair. Subjects included 24 patients at ≥18 months after ACL reconstruction and 22 control subjects with no history of knee injury. A series of cross-sectional magnetic resonance images were obtained to compare the QF of patients' injured side with that of their uninjured sides and that of uninjured control subjects. Muscle torque per muscle volume was calculated as isokinetic peak torque divided by QF muscle volume (cm3). The mean muscle torque per unit volume of the injured side of patients was not significantly different from that of the uninjured side or control subjects (one-way ANOVA) Results of the present study were contrary to the results of a previous study that evaluated patients at ≤12 months after ACL reconstruction. The present study found that high-threshold motor unit recruitment was restored at ≥18 months after ACL reconstruction. Thus, clinicians must develop techniques that increase the recruitment of high-threshold motor units in the QF from the period immediately after the injury until approximately 18 months after ACL reconstruction. [ABSTRACT FROM AUTHOR]

Aims: Reticulon 3 (RTN3), a member of the reticulon family of proteins, interacts with the β-secretase, β-site amyloid precursor protein-cleaving enzyme 1 (BACE1), and inhibits its activity to produce β-amyloid protein. The aim of the present study was to clarify the biological role of RTN3 in the brain and its potential involvement in the neuropathology of Alzheimer's disease (AD). Methods: We performed immunohistochemical and biochemical analyses using a specific antibody against RTN3 to investigate the expression and subcellular localization of RTN3 in control and AD brain tissue samples. Results: Western blot analysis revealed no significant differences in the RTN3 levels between control and AD brains. Immunohistochemical staining showed that RTN3 immunoreactivity was predominantly localized in pyramidal neurones of the cerebral cortex. The patterns of RTN3 immunostaining were similar in control and AD cerebral cortices, and senile plaques were generally negative for RTN3. Biochemical subcellular fractionation disclosed that RTN3 colocalized with BACE1 in various fractions, including the endoplasmic reticulum and the Golgi apparatus. Double-immunofluorescence staining additionally indicated that RTN3 was localized in both endoplasmic reticulum and Golgi compartments in neurones. Conclusions: These results show that RTN3 is primarily expressed in pyramidal neurones of the human cerebral cortex and that no clear difference of RTN3 immunoreactivity is observable between control and AD brains. Our data also suggest that there is considerable colocalization of RTN3 with BACE1 at a subcellular level. [ABSTRACT FROM AUTHOR]

The giant river shrimp ( Macrobrachium rosenbergii), a native species of Thailand, is either exported for commercial purposes or supplied to meet the local requirements in Thailand. Limited pharmacokinetic information of the major antibiotic, oxytetracycline (OTC), is available for this freshwater shrimp. The purpose of the present study was to investigate the muscle tissue kinetics of OTC in M. rosenbergii following either intramuscular (i.m.) or oral (p.o.) administration at two dosages of 11 and 22 mg/kg body weight (b.w.). The concentration of OTC in shrimp tissues was measured using high-performance liquid chromatography (HPLC) equipped with a fluorescence detector. Muscle tissue concentrations were below the detection limit (LOD, 0.1 μg/g) after 96 and 120 h, following i.m. and p.o. administration, respectively. Peak muscle concentrations (Cmax) were 3.47 and 1.73 μg/g after i.m. and p.o. administration at a single dose of 11 mg/kg b.w. whereas they were 6.03 and 2.51 μg/g at a single dose of 22 mg/kg b.w., respectively. A noncompartment model was developed to describe the pharmacokinetics of OTC in the giant freshwater shrimp. The terminal half-lives of OTC were 28.68 and 28.09 h after i.m. and p.o. administration at a single dose of 11 mg/kg b.w., but 29.95 and 27.03 h at a single dose of 22 mg/kg b.w., respectively. The relative bioavailability was 82.32 and 64.67% following i.m. and p.o. administration, respectively. Based on the pharmacokinetic data, i.m. and p.o. administration with OTC at a dose of 11 mg/kg b.w. would be appropriate for use in giant freshwater shrimp farming. To avoid the OTC residue in shrimp muscle, it should take at least seven half-lives (8 days) to wash out the drug from the muscle of M. rosenbergii. [ABSTRACT FROM AUTHOR]

Background and Purpose: Many in vitro and fewer in vivo studies have shown that tetracyclines present anti-inflammatory activity. We investigated if a novel non-antibacterial, non-chelating hydroxypyrazoline derivative of minocycline, 12S-hydroxy-1,12-pyrazolinominocycline (PMIN), also induced antinociceptive and anti-inflammatory effects.Experimental Approach: Antibacterial effects against a minocycline-sensitive Staphylococcus aureus strain were evaluated by applying a cylinder-plate agar diffusion technique. Antibacterial effects of diluted serum from mice pre-treated with minocycline or PMIN were also evaluated. Ca2+ binding activity was assessed by spectrophotometry. Formalin-induced nociceptive responses and carrageenan-induced paw oedema were evaluated in mice. The rota-rod apparatus was used to evaluate motor coordination.Key Results: Minocycline, but not PMIN, inhibited bacterial growth. Serum from mice treated with minocycline, but not with PMIN, also induced such an effect. The UV absorption spectrum of solutions of minocycline, but not those of PMIN, was markedly changed in the presence of Ca2+. Minocycline or PMIN inhibited both phases of formalin-induced nociception and carrageenan-induced paw oedema. It is unlikely that antinociception resulted from lack of motor coordination, as tetracycline did not impair the performance of mice on the rotating rod.Conclusions and Implications: These results indicate that inhibition of nociception and oedema by tetracyclines is neither necessarily linked to antibacterial nor to Ca2+ chelating activities. This study supports the evaluation of the potential usefulness of PMIN in the treatment of painful and inflammatory diseases, as its lack of antibacterial and Ca2+ chelating activities might confer greater safety over conventional tetracyclines. [ABSTRACT FROM AUTHOR]

This study was performed to obtain evidence regarding bilateral hindrance of motor unit (MU) recruitment in the quadriceps femoris (QF) of patients with anterior cruciate ligament (ACL) reconstruction. The subjects included 70 patients who underwent ACL reconstruction and 35 healthy subjects. To identify the muscle torque per unit volume (MTPUV), the peak torque of each velocity of isokinetic performance was divided by muscle volume of the QF measured by a series of cross-sectional images obtained by magnetic resonance imaging scans. Tests revealed that the mean MTPUV of the uninjured (0.113±0.03 N m/cm3 at 60°/s, 0.081±0.02 N m/cm3 at 180°/s) and injured sides (0.109±0.03 N m/cm3 at 60°/s, 0.079±0.023 N m/cm3 at 180°/s) were significantly lower than those of the control group (0.144±0.05 N m/cm3 at 60°/s, 0.096±0.04 N m/cm3 at 180°/s). Previous studies suggested that MU recruitment in the QF of patients with ACL injury was hindered bilaterally. However, the design of their studies could not provide evidence of bilateral hindrance of MU recruitment in the QF. The results of the present study demonstrated that the MTPUV of both injured and uninjured sides of patients were significantly lower than those of the control group. [ABSTRACT FROM AUTHOR]

No information is available about the effects of Japanese radish sprout (JRS) on diabetes. To clarify the effects, the influence of JRS on carbohydrate and lipid metabolisms was investigated in normal and streptozotocin-induced diabetic rats. The rats were fed a diet containing 0%, 2.5% or 5% of JRS ad libitum for 21 days. Compared with the corresponding control groups, the JRS-fed normal rats showed lower plasma levels of total cholesterol (TC), triglycerides (TG), phospholipids (PL), fructosamine, glucose and insulin and higher plasma levels of low-density lipoprotein-cholesterol, whereas the JRS-fed diabetic rats showed lower plasma levels of fructosamine, glucose and insulin without changes in the plasma lipid parameters. JRS also decreased the hepatic TC, TG and PL levels in the normal rats and the TG level in the diabetic rats. These results showed that JRS had a hypoglycemic activity in both the normal and diabetic rats and partly improved lipid metabolism in the normal rats. JRS has the potential to alleviate hyperglycemia in cases where diabetes is present and to serve in the primary prevention of diabetes mellitus. [ABSTRACT FROM AUTHOR]

The daily periodicity of growth increment formation in sagittal otoliths of jack mackerelTrachurus japonicuswas validated by marking otoliths with alizarin complexone(ALC). Analysis of otoliths of known-age juveniles confirmed that the first increment formed on day 3 after hatching, and was associated with first feeding. A total of 198 specimens, ranging from 2·6 to 49·2 mm in body length(notochord length or standard length) and from 7 to 78 days in age, were collected in the East China Sea and Tosa Bay, and used to examine the association between otolith morphological development and ontogenetic development. The relationship between body length( L) and otolith radius( R) was significantly described by the linear functionL = 2·65 + 0·0425R( n = 198,r2 = 0·99,P < 0·001), indicating that somatic growth history can be reconstructed from otolith growth patterns. The otolith was primarily spherical in the preflexion larval stage, and became elongated with notochord flexion. The first secondary primordium formed atc. 25 days, during the middle postflexion stage, and was associated with metamorphosis. Byc. 42 days the sagittal otolith was adult-like in morphology, with the primary growth zone enclosed by the marginal growth zone, except in the anterior rostrum area. Thus age, growth and developmental stages were recorded in sagittal otoliths during the larval and early juvenile stages of jack mackerel. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate gamma loop function in the quadriceps femoris muscle in patients who with less than 6 month-history of anterior cruciate ligament ACL) reconstruction. For this purpose, we compared the response to vibration stimulation in 10 patients with ACL repair and 12 normal healthy subjects, by measuring the maximal voluntary isometric contraction MVC) and integrated electromyograms I-EMG) of the quadriceps muscles. Pre-vibration data were obtained from each subject by measuring the MVC of the knee extension and the I-EMG from the vastus medialis, vastus lateralis, and rectus femoris muscles. Vibration stimulation was applied to the infrapate!!ar tendons, followed immediately by repeating the MVC and I-EMG recording. Prolonged vibration resulted in a significant decrease of both MVC and I-EMG in the control group. In contrast, the same stimulus failed to elicit changes in ACL-repair group. Our results suggest the presence of abnormal gamma loop function in the quadriceps femoris muscle of patients with ACL repair, which may explain the muscle weakness often described in such patients. [ABSTRACT FROM AUTHOR]

Activity-dependent synaptic plasticity has been thought to be a cellular basis of memory and learning. The late phase of long-term potentiation (L-LTP), distinct from the early phase, lasts for up to 6 h and requires de novo synthesis of mRNA and protein. Many LTP-related genes are enhanced in the hippocampus during pentyrenetetrazol (PTZ)- and kainate (KA)-mediated neural activation. In this study, mice were administered intraperitoneal injections of PTZ 10 times, once every 48 h, and showed an increase in seizure indexes. Genes related to plasticity were efficiently induced in the mouse hippocampus. We used a PCR-based cDNA subtraction method to isolate genes that are expressed in the hippocampus of repeatedly PTZ-treated mice. One of these genes, neural activity-related RING finger protein (NARF), encodes a new protein containing a RING finger, B-box zinc finger, coiled-coil (RBCC domain) and β-propeller (NHL) domain, and is predominantly expressed in the brain, especially in the hippocampus. In addition, KA up-regulated the expression of NARF mRNA in the hippocampus. This increase correlated with the activity of the NMDA receptor. By analysis using GFP-fused NARF, the protein was found to localize in the cytoplasm. Enhanced green fluorescent protein-fused NARF was also localized in the neurites and growth cones in neuronal differentiated P19 cells. The C-terminal β-propeller domain of NARF interacts with myosin V, which is one of the most abundant myosin isoforms in neurons. The NARF protein increases in hippocampal and cerebellar neurons after PTZ-induced seizure. These observations indicated that NARF expression is enhanced by seizure-related neural activities, and NARF may contribute to the alteration of neural cellular mechanisms along with myosin V. [ABSTRACT FROM AUTHOR]

A wheel loader is the major machine that has been used in several fields for scooping, carrying, and loading of crushed ores. Recently, automation of the wheel loader task has been receiving considerable attention. This article describes a path-generation method for autonomous locomotion of the wheel loader. From the viewpoint of locomotion stability and ease of control, it is necessary for the path to be smooth and easily calculated. In order to satisfy these conditions, a path-generation method using a clothoid curve is proposed. The change in curvature of the clothoid curve is continuous and is proportional to the length of the curve. Therefore, the clothoid curve provides continuous change of the steering angle. Furthermore, an interpolation method between the initial and target points of the wheel loader is proposed in this study, which consists of the clothoid curve segment and a straight-line segment. A V-shaped curve including the backward path and the forward path is also generated, taking into account the avoidance of rapid turning. [ABSTRACT FROM AUTHOR]

To clarify the biliary immune response against food antigen, we studied biliary antibody response to intravenous and oral primary immunization with ovomucoid (OM) and the effects of cholera toxin B subunit (CTB) on the oral response in mice. Specific antibodies against OM were induced in biliary and serum immunoglobulin (Ig) A, IgG and IgM by intravenous (i.v.) administration of the antigen. However the antibodies were induced only in biliary Igs, but not in serum Igs, by oral intubation of the antigen. The higher levels of anti-OM in bile than in serum observed in the oral group may favour the assumption that antigen-stimulted lymphoid cells migrate to the liver, gall bladder or bile duct where they produce antibody. Both serum and biliary anti-OM responses to oral immunization were potentiated remarkably by oral administration of CTB with the antigen, the IgM anti-OM response being potentiated to the largest extent. In the CTB-treated mice, the IgA anti-OM level was higher in bile than in serum. Serum level of IgG anti-OM was much lower in the CTB-treated mice than in the i.v.-immunized mice, but the biliary level of IgG anti-OM in the CTB-treated mice was comparable to that in the i.v.-immunized mice. The relationship between serum and biliary IgA and IgG antibodies suggests that CTB potentiates biliary anti-OM responses not solely through increasing systemic levels of the antibodies but through modulating the processes specific to mucosal presentation of antigen. [ABSTRACT FROM AUTHOR]

Describes a case of uterine rupture at parturition subsequent to previously repeated cervical surgeries. Discussion on uterine rupture.

In recent years, there has been increasing attention towards understanding the relationship between age-related alterations in the oral microbiota and age-associated diseases, with reports emphasizing the significance of maintaining a balanced oral microbiota for host health. However, the precise mechanisms underlying age-related changes in the oral microbiota remain elusive. We recently reported that cellular senescence of ileal germinal center (GC) B cells, triggered by the persistent presence of commensal bacteria, results in diminished IgA production with aging and subsequent alterations in the gut microbiota. Consequently, we hypothesize that a similar phenomenon may occur in the oral cavity, potentially contributing to age-related changes in the oral microbiota. Examination of p16-luc mice, wherein the expression of the senescent cell marker p16 INK4a can be visualized, raised under specific pathogen-free (SPF) or germ-free (GF) conditions, indicated that, unlike ileal GC B cells, the accumulation of senescent cells in GC B cells of cervical lymph nodes increases with age regardless of the presence of commensal bacteria. Furthermore, longitudinal studies utilizing the same individual mice throughout their lifespan revealed concurrent age-related alterations in the composition of the oral microbiota and a decline in salivary IgA secretion. Further investigation involving Rag1 -/- mice transplanted with B cells from wild-type or p16 INK4a and p21 Waf1/Cip1 -double knockout mice unveiled that B cell senescence leads to reduced IgA secretion and alteration of the oral microbiota. These findings advance our understanding of the mechanism of age-associated changes in the oral microbiota and open up possibilities of their control., (© 2024 The Author(s). Aging Cell published by Anatomical Society and John Wiley & Sons Ltd.)

Background: Mitral annuloplasty is a reliable mitral valve repair technique. There are two types of annuloplasy rings: the rigid ring and the flexible ring. This study sought to examine the long-term results of mitral valve repair using a Duran flexible ring., Methods: We retrospectively reviewed 226 patients who underwent primary mitral valve repair using the Duran flexible ring for mitral regurgitation between September 1994 and March 2003. Patients' mean age was 56.7 years, and 39% were female. The mean follow-up was 10.6 years (0.04 ∼ 18.3), and echocardiographic follow-up was 83.3% complete., Results: There were three early and 25 late deaths. Survival was 89.3 ± 2.2 for 10 years, and 83.5 ± 3.2% for 15 years. The 10- and 15-year freedom from reoperation on the mitral valve were 96.4 ± 1.4 and 95.3 ± 1.7%, respectively. The 10- and 15-year freedom from moderate or severe mitral regurgitation were 92.5 ± 2.2 and 73.7 ± 7.1%, respectively. Cox regression analysis revealed that age, male gender, and isolated anterior leaflet prolapse were predictive of recurrent moderate or severe mitral regurgitation., Conclusions: Mitral valve repair for mitral regurgitation using a flexible Duran ring is safe and durable for more than 10 years., (© 2015 Wiley Periodicals, Inc.)

To elucidate the effect of fungal hyphae on the behaviour of Shiga toxin-producing Escherichia coli (STEC) O157, the spread and change in stress resistance of the bacterium were evaluated after coculture with 11 species of food-related fungi including fermentation starters. Spread distances of STEC O157 varied depending on the co-cultured fungal species, and the motile bacterial strain spread for longer distances than the non-motile strain. The population of STEC O157 increased when co-cultured on colonies of nine fungal species but decreased on colonies of Emericella nidulans and Aspergillus ochraceus. Confocal scanning microscopy visualization of green fluorescent protein-tagged STEC O157 on fungal hyphae revealed that the bacterium colonized in the water film that existed on and between hyphae. To investigate the physiological changes in STEC O157 caused by co-culturing with fungi, the bacterium was harvested after 7 days of co-culturing and tested for acid resistance. After co-culture with eight fungal species, STEC O157 showed greater acid resistance compared to those cultured without fungi. Our results indicate that fungal hyphae can spread the contamination of STEC O157 and can also enhance the stress resistance of the bacteria., (© 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Hypertension is one of the major complications in neurofibromatosis type 1 (NF1). It is known to be caused by renal artery stenosis or pheochromocytoma. However, more than half of hypertensive patients with NF1 do not have either disorder. We report here on a 13-year-old male with NF1 who had hypertension and a stenosis of the right renal artery associated with elevated renal vein renin on the diseased side. He underwent percutaneous transluminal renal angioplasty. In spite of successful dilation of the artery and normalized renin level, high blood pressure persisted beyond 6 months requiring antihypertensive medication. His wide pulse pressure suggested arterial stiffness due to NF1 vasculopathy. We posit that the cause of hypertension in this patient was considered to be arterial stiffness ascribed to NF1 vasculopathy rather than renal artery stenosis. Increased pulse pressure supports the hypothesis. This marker of arterial stiffness can be assessed non-invasively and should be evaluated routinely in NF1., (Copyright © 2013 Wiley Periodicals, Inc.)

An axial self-bearing motor is proposed which can drive an axial blood pump without physical contact. It is a functional combination of the bi-directional disc motor and the axial active magnetic bearing, where it actively controls single degree-of-freedom motion, while other motions such as lateral vibration are passively stable. For application to a blood pump, the proposed self-bearing motor has the advantages of simple structure and small size. Through the finite element method (FEM) analysis and the experimental test, its good feasibility is verified. Finally, the axial flow pump is fabricated using the developed magnetically suspended motor. The pump test is carried out and the results are discussed in detail.

The method of measuring the flow rate of a centrifugal blood pump from the input electric power, which will be indispensable for the long-term use of such devices, was developed and was applied to the direct-driven centrifugal blood pump that has been developed by our research group. The accuracy was evaluated in a chronic animal experiment using an adult goat. The results demonstrated that this method carries the sufficient potential of the instantaneous monitoring method, but errors due to electromagnetic and mechanical losses were not determined always precisely. The detection of adverse phenomena such as the obstruction of the inlet cannula was also possible from the estimated value of the flow rate and its waveform pattern.

The authors studied avoidance of coagulation occurrence using computational fluid dynamics (CFD) analysis from the fluid dynamical point of view. Concerning centrifugal pumps, blood coagulation sometimes occurs at the region behind the impeller where the flow is generally stagnant. Therefore, we conducted a thorough study with the specimen pump with and without washout holes, mocking up the Nikkiso HPM-15. As the result, the model with washout holes indicated that the fluid rotates rapidly at the vicinity of the shaft and generates washout effects near the stationary rear casing. On the other hand, the model without washout holes showed that fluid cannot be quickly shipped out of the area behind the impeller and rotates mildly around the shaft. To clarify the moving relations between the impeller and the fluid, validation studies by comparing the results of CFD analysis and flow visualization experiments are ongoing; thus far, the studies show that CFD results are similar to the results from flow visualization experiments.

Antibodies specific to Salmonella enteritidis (S.E.) were obtained from immunized egg yolk, and their protective effects against S.E. were studied by using monolayer-cultured human intestinal epithelial cells, Caco-2 and T84. The Salmonella adherence and entry to the cells were partially inhibited by the antibodies. The antibodies inhibited the decrease in transepithelial electrical resistance (TEER) of the intestinal epithelial monolayers and IL-8 secretion of the cells induced by S.E. invasion. Also, the antibodies blocked the penetration of bacteria through the cell layer although they did not inhibit the growth of bacteria in the cells. Confocal microscopic photographs revealed the bacteria in the infected monolayer cells were bound to antibodies. These results indicate that anti-S.E. antibodies may protect the cells from destruction induced by S.E. invasion in intestinal epithelial cells in addition to the partial inhibition of adhesion and invasion of S.E. at the cell surface. Passive antibodies against invasive bacteria would be useful to prevent the migration of S.E. to blood not only at the cell surface but also inside of intestinal epithelial cells.

A correlation study was conducted among quantitative flow visualization analysis, computational fluid dynamic analysis, and hemolysis tests regarding the flow in a centrifugal blood pump to prevent hemolysis. Particular attention was paid to the effect of the impeller/casing gap widths on the flow in the volute and in the outlet. Flow vector maps were obtained for 250% scaled-up models with various geometries, using an argon ion laser light sheet, a high speed video camera, and particle tracking velocimetry. In terms of the results, in the small radial gap model, high shear occurred near the inside wall of the outlet and stagnation near the outside wall of the outlet whereas the standard model maintained smooth flow and low shear. The small radial gap model showed a lower head and greater hemolysis than the standard model. This head decrease could be partly restored by relocating the outlet position; however, the hemolysis level hardly decreased. From these results, it was found that the small radial gap itself is important. It was also confirmed by detailed flow visualization and simple laminar shear analysis near the wall that the small radial gap caused a wider high shear layer (110-120 microm) than the standard model (approximately 80 microm). In the small radial gap model, the high shear layer in the outlet (approximately 50 microm) is much narrower than that in the volute. Flow visualization together with the aid of computational fluid dynamic analysis would be useful to eliminate the causes of hemolysis.

The purpose of this study was to examine the relationship between local flow conditions and the hemolysis level by integrating hemolysis tests, flow visualization, and computational fluid dynamics to establish practical design criteria for centrifugal blood pumps with lower levels of hemolysis. The Nikkiso centrifugal blood pump was used as a standard model, and pumps with different values of 3 geometrical parameters were tested. The studied parameters were the radial gap between the outer edge of the impeller vane and the casing wall, the position of the outlet port, and the discharge angle of the impeller vane. The effect of a narrow radial gap on hemolysis was consistent with no evidence that the outlet port position or the vane discharge angle affected blood trauma in so far as the Nikkiso centrifugal blood pump was concerned. The radial gap should be considered as a design parameter of a centrifugal blood pump to reduce blood trauma.

To establish an efficient design process for centrifugal blood pumps, the results of computational fluid dynamics (CFD) analysis were compared to the results of flow visualization tests and hemolysis tests, using the Nikkiso centrifugal blood pump. CFD analysis revealed that the radial gap greatly affected the shear stress in the outlet diffuser. The hemolysis study also indicated a similar tendency. To see the flow behind the impeller, we conducted a comparative study between models with and without washout holes using the CFD technique. CFD analysis indicated that flow and pressure distributions behind the impeller were different between both models, and a particle was observed to remain longer behind the impeller in the model without washout holes. In the future, CFD analysis could be a useful tool for developing blood pumps in comparison to flow visualization tests and hemolysis tests.