Microgravity studies of solidification patterns in model transparent alloys onboard the International Space Station

We review recent in situ solidification experiments using nonfaceted model transparent alloys in science-in-microgravity facilities onboard the International Space Station (ISS), namely the Transparent Alloys (TA) apparatus and the Directional Solidification Insert of the DEvice for the study of Critical Liquids and Crystallization (DECLIC-DSI). These directional-solidification devices use innovative optical videomicroscopy imaging techniques to observe the spatiotemporal dynamics of solidification patterns in real time in large samples. In contrast to laboratory conditions on ground, microgravity guarantees the absence or a reduction of convective motion in the liquid, thus ensuring a purely diffusion-controlled growth of the crystalline solid(s). This makes it possible to perform a direct theoretical analysis of the formation process of solidification microstructures with comparisons to quantitative numerical simulations. Important questions that concern multiphase growth patterns in eutectic and peritectic alloys on the one hand and single-phased, cellular and dendritic structures on the other hand have been addressed, and unprecedented results have been obtained. Complex self-organizing phenomena during steady-state and transient coupled growth in eutectics and peritectics, interfacial-anisotropy effects in cellular arrays, and promising insights into the columnar-to-equiaxed transition are highlighted.

Large-Scale Channel Migration in the Sittang River Estuary

An estuary is a dynamic environment where marine and fluvial processes meet to form complex and transient morphology. The estuary morphology is largely determined by net sediment transport by two-way tidal flows, but the hydrodynamics also depends on the morphology of the tidal channels. The estuary inherently accommodates cyclic processes that are internally generated through hydro-morphodynamic interactions. In addition, the estuary evolves in response to changes in external forces by natural and anthropogenic factors. Morphological changes under the different controls often hinder the comprehension of the evolutionary processes of estuaries. Here we explored morphological changes in the Sittang River estuary, Myanmar, which has great morphological dynamism from extreme tidal energy and large sediment inputs, through field surveys and satellite imagery analysis. We identify an autocyclic process in a sedimentary system driving large-scale channel migration in decadal to multidecadal cycles. We show that drastic changes of the estuary morphology occasionally occur with rapid bank erosion through modulation of the cyclic channel migration under conflicting tidal and fluvial forces. This extreme case with minimal human intervention highlights channel migration as a key process in morphological evolution of tide-dominated estuaries undergoing active infilling.

Percutaneous Transluminal Angioplasty for Intracranial Atherosclerotic Stenosis

Eleven patients with symptomatic intracranial atherosclerotic stenotic lesions underwent percutaneous transluminal angioplasty (PTA). Seven patients had stenosis in M1 segment of the middle cerebral artery (MCA), two in the cavernous internal carotid artery, one in M2 segment of the MCA and one in the P2 segment of the posterior cerebral artery. Initial successful dilatation (less than 50% residual stenosis) was obtained in nine patients (81.8%). Permanent neurological deficit related to PTA was seen in one patient and transient symptoms were observed in two. Re-stenosis was revealed in two cases (18.2%) in the early follow-up period. All patients with successful dilatation and without re-stenosis never had TIA or stroke after PTA. Intracranial PTA is an effective procedure, but several problems remain to be solved.

A novel method for rapid detection of Streptococcus pneumoniae antigens in blood

In this study, we used "RAPIRUN(®)Streptococcus pneumoniae HS (otitis media/sinusitis) (RAPIRUN-HS)," a rapid S. pneumoniae antigen detection kit, to investigate methods for detecting S. pneumoniae antigens in blood of 32 bacterial pneumonia patients. We simultaneously performed PCR to detect S. pneumoniae in blood samples. The results of these tests were compared based on pneumonia severity, determined using the Pneumonia Severity Index (PSI) score classification. Four S. pneumoniae PCR-positive patients of the six severe pneumococcal pneumonia patients (PSI risk class IV/V) also tested positive using RAPIRUN-HS. Twenty-four mild to moderate pneumonia patients (PSI risk class I-III) were S. pneumoniae PCR-negative; of these, 21 tested negative using RAPIRUN-HS. The pneumococcal pneumonia patients testing positive using RAPIRUN-HS had low leukocyte counts and elevated C-reactive protein and procalcitonin levels, indicating that RAPIRUN-HS results were correlated with pneumonia severity. The time course evaluations of the laboratory tests for severe pneumococcal pneumonia patients showed that RAPIRUN-HS and S. pneumoniae PCR yielded positive results earlier than the changes in procalcitonin and IL-6. Thus, concomitant pneumococcal bacteremia was strongly suspected in patients testing positive using RAPIRUN-HS. In conclusion, RAPIRUN-HS may be useful for determining whether to admit patients into hospitals and selecting the appropriate antimicrobial agents.

Ribavirin dose reduction during telaprevir/ribavirin/peg-interferon therapy overcomes the effect of the ITPA gene polymorphism

Treatment success of chronic hepatitis C virus genotype 1 infection has improved with the advent of telaprevir plus peg-interferon/ribavirin triple combination therapy. However, the effect of inosine triphosphatase (ITPA) polymorphism on dose reduction during triple therapy, especially during the postmarketing phase, has not been sufficiently evaluated. We analysed 273 patients with genotype 1 infection who were treated with triple therapy and assessed the effect of the ITPA polymorphism on dose reduction. ITPA and IFNL4 SNP genotypes were determined by the Invader assay. A stepwise multivariate regression analysis was performed to identify factors associated with outcome of the therapy. The overall sustained viral response (SVR) rate 12 weeks after the end of therapy was 80.2% (219/273). Decline of haemoglobin was significantly faster, and ribavirin was more extensively reduced in patients with ITPA SNP rs1127354 genotype CC than CA/AA. Extensive reduction of ribavirin resulted in mild reduction of telaprevir and peg-interferon, but no significant increase in viral breakthrough. Although the amount of telaprevir given was slightly higher in CA/AA patients, the total dose of peg-interferon and the SVR rate did not differ between the two groups. Multivariate analysis showed that IFNL4 but not ITPA SNP genotype, platelet count and peg-interferon adherence were significantly associated with outcome of therapy. Postmarketing-phase triple therapy resulted in a high SVR rate in spite of extensive ribavirin dose reduction in a diverse patient population, indicating the importance of treatment continuation and appropriate management of adverse events.

Decreased serum chemerin levels in male Japanese patients with type 2 diabetes: sex dimorphism

Chemerin, a recently discovered adipocytokine plays an important role in obesity and obesity-associated metabolic complications. However, the role of chemerin in the pathogenesis of type 2 diabetes mellitus (T2DM) has not fully been elucidated. We compared the serum chemerin levels and metabolic parameters between 88 control subjects, 86 patients with metabolic syndrome (MS), and 147 patients with T2DM in a Japanese population and further analyzed their correlation. Enzyme-linked immunosorbent assay was used to measure the serum chemerin levels. The chemerin levels were significantly higher in male than in female control subjects (p < 0.005), with significant decreases in patients with T2DM compared with those with MS and control subjects (164.9 ± 6.3 ng/mL vs. 209.8 ± 7.7 and 218.7 ± 7.3 ng/mL; p < 0.0001 vs. p < 0.0001, respectively) but no significant differences in female subjects. The multiple regression analysis revealed that the chemerin levels negatively correlated with the fasting glucose and HbA1c levels in total and male subjects. In the patients with T2DM, the chemerin levels negatively correlated with fasting glucose and high-density lipoprotein cholesterol but positively correlated with body mass index (BMI), and total cholesterol and triglyceride levels. The negative correlation between the chemerin and fasting glucose levels remained significant after adjustment for age, sex, and BMI in the total and male subjects and those with T2DM. These results suggest the role of chemerin in sex dimorphism and a potential link between chemerin levels and T2DM pathogenesis in a Japanese population.

Binding of adiponectin and C1q in human serum, and clinical significance of the measurement of C1q-adiponectin / total adiponectin ratio

OBJECTIVE

Adiponectin and C1q have similar sequences, exist abundantly in blood, and are produced by adipose tissues. The aim of this study was to examine whether adiponectin and C1q form protein-complex in blood and to know the clinical significance of the C1q-adiponectin (C1q-APN) complex in serum.

METHODS

The direct interaction between adiponectin and C1q was investigated by far western blotting and co-immunoprecipitation. The relationship between serum C1q-APN and various clinical features was analyzed in 329 Japanese men who underwent health check-up, including measurements of visceral (VFA) and subcutaneous fat area (SFA) by computed tomography (Victor-J study).

RESULTS

Adiponectin bound to C1q in vitro and C1q-APN complex existed in human blood. C1q-APN complexes were identified in high- and middle-molecular weight forms of adiponectin in human serum by gel-filtration chromatography. Stepwise multiple regression analysis identified body mass index, VFA and SFA as significant determinants of serum C1q-APN level. Serum C1q-APN/Total-APN ratio correlated positively with cardiovascular risk factor accumulation in subjects with VFA ≥100 cm(2).

CONCLUSIONS

These results indicate that high- and middle-molecular forms of adiponectin partly consist of adiponectin-complex with other proteins including C1q and that the blood C1q-APN/Total-APN ratio may serve as a biomarker of the metabolic syndrome in general male subjects.

Calcium [¹³C]carbonate breath test for quantitative measurement of total gastric acid in rats

OBJECTIVE

A traditional measurement of gastric acid, involving nasogastric intubation of stomach and acid suction, has been suggested as a gold standard. However, this causes the patient discomfort and cost increase, and is 'time-consuming'.

MATERIAL AND METHODS

A calcium [(13)C]carbonate (Ca(13)CO(3)) breath test was carried out in rats without or with concomitant drugs omeprazole (OMP) and pentagastrin (PG) known as an inhibitor and an inducer of acid, respectively. This test was aimed at evaluating a correlation between the breath response and the total amount of gastric acid. To search for an absorption pathway of (13)CO(2) gas produced by the reaction of Ca(13)CO(3) with hydrochloric acid in the stomach of rats, we compared the breath responses after intra-gastric administration of (13)CO(2) gas and sodium [(13)C]bicarbonate (NaH(13)CO(3)).

RESULTS

A linear relationship of the breath parameter (breath-C(max)) with the dose of Ca(13)CO(3) was obtained in the range of 4-200 µmol/kg. However, theses parameters were saturated at >200 µmol/kg. The direct correlation between the breath-C(max) and the total amount of gastric acid in rats with or without OMPs or PG (r = 0.994) demonstrated that the change in breath response is an accurate or sensitive indicator of the total amount of gastric acid. (13)CO(2) gas generated in the rat stomach was likely to diffuse across the stomach wall as (13)CO(2) gas directly into the blood plasma.

CONCLUSIONS

The present study showed that Ca(13)CO(3) breath test is a good tool to accurately predict the total amount of gastric acid.

A novel method for rapid detection of Streptococcus pneumoniae antigen in sputum and its application in adult respiratory tract infections

A highly sensitive immunochromatography test kit, ODK0501, was developed using specific polyclonal antibodies against the C-polysaccharide moiety of Streptococcus pneumoniae for the rapid detection of S. pneumoniae antigen in sputum samples. The clinical utility of ODK0501 for this detection was evaluated prospectively in 52 adult patients with respiratory infections and compared with that of a urinary antigen detection kit. Overall, 21 patients (40.4 %) showed positive results with ODK0501, compared with 16 patients (30.8 %) using the urinary antigen detection kit, and S. pneumoniae was cultured from 18 patients. ODK0501 and the urinary antigen detection kit exhibited a sensitivity of 94.4 and 55.6 % (P<0.01), respectively, and a specificity of 88.2 and 82.4 %, respectively. Eleven of thirteen patients with conflicting results between the two test kits exhibited consistent results for sputum cultures. Moreover, eight out of nine patients positive for ODK0501 and negative for the urinary antigen detection kit were S. pneumoniae culture-positive, including five who exhibited phagocytosis, indicating S. pneumoniae as a causative agent of infection, in Gram staining of sputum samples. These results suggest that the ODK0501 direct sputum detection kit is more clinically useful than the urinary antigen detection kit in adult patients with respiratory infections.

Feedback control of unstable cellular solidification fronts

We present a feedback control scheme to stabilize unstable cellular patterns during the directional solidification of a binary alloy. The scheme is based on local heating of cell tips which protrude ahead of the mean position of all tips in the array. The feasibility of this scheme is demonstrated using phase-field simulations and, experimentally, using a real-time image processing algorithm, to track cell tips, coupled with a movable laser spot array device to heat the tips locally. We demonstrate, both numerically and experimentally, that spacings well below the threshold for a period-doubling instability can be stabilized. As predicted by the numerical calculations, cellular arrays become stable with uniform spacing through the feedback control which is maintained with minimal heating.

Immunohistochemical detection of an AGE, a ligand for macrophage receptor, in peritoneum of CAPD patients

BACKGROUND

In patients on long-term continuous ambulatory peritoneal dialysis (CAPD), ultrafiltration (UF) capacity of peritoneal membrane may be impaired due to accumulation of advanced glycation end products (AGEs). This study aimed to elucidate the characteristics of a novel anti-AGE antibody, ODI-GLC19, and to demonstrate AGE accumulation in the peritoneum of CAPD patients using the antibody.

METHODS

A monoclonal anti-AGE antibody (ODI-GLC19) was prepared by immunizing female balb/c mice using D-glucose-modified keyhole limpet hemocyanin. The characteristics of ODI-GLC19 were determined by enzyme-linked immunosorbent assay and receptor binding inhibition assay. Immunohistochemistry using ODI-GLC19 was performed to detect AGE in peritoneal tissues obtained from patients with nonrenal disease, and CAPD patients with normal and low UF.

RESULTS

ODI-GLC19 reacted with glycolaldehyde-modified BSA (GA-BSA) and glucose-modified BSA (GLC-BSA), but not with imidazolone or N epsilon-(carboxymethyl)lysine. GA-BSA and GLC-BSA strongly bound to cultured macrophages. Time-dependent recognition of newly formed GA-BSA by ODI-GLC19 was similar to that by macrophages. The binding of GA-BSA to macrophages was inhibited by ODI-GLC19 in a dose-dependent manner. Immunohistochemical studies revealed that ODI-GLC19-positive AGE was exclusively detected in peritoneal cells including macrophages, and its staining intensity was more prominent in the peritoneum of CAPD patients, especially with low UF, than in patients with nonrenal disease.

CONCLUSIONS

A novel monoclonal anti-AGE antibody, ODI-GLC19, recognizes a ligand for an AGE receptor on macrophages. Incorporation of AGE into peritoneal cells including macrophages may be involved in progressive peritoneal dysfunction in CAPD patients.

Surface effects in nucleation and growth of smectic-B crystals in thin samples

We present an experimental study of the surface effects (interactions with the container walls) during the nucleation and growth of smectic-B (SmB) crystals from the nematic in free growth and directional solidification of a mesogenic molecule [C4H9-(C6H10)2CN] called CCH4 in thin (of thickness in the 10-microm range) samples. We follow the dynamics of the system in real time with a polarizing microscope. The inner surfaces of the glass-plate samples are coated with polymeric films, either rubbed polyimid (PI) films or mono-oriented poly(tetrafluoroethylene) (PTFE) films deposited by friction at high temperature. The orientation of the nematic and the smectic-B is planar. In PI-coated samples, the orientation effect of SmB crystals is mediated by the nematic, whereas, in PTFE-coated samples, it results from a homoepitaxy phenomenon occurring for two degenerate orientations. A recrystallization phenomenon partly destroys the initial distribution of crystal orientations. In directional solidification of polycrystals in PTFE-coated samples, a particular dynamics of faceted grain boundary grooves is at the origin of a dynamical mechanism of grain selection. Surface effects also are responsible for the nucleation of misoriented terraces on facets and the generation of lattice defects in the solid.

Pattern stability and trijunction motion in eutectic solidification

We demonstrate by both experiments and phase-field simulations that lamellar eutectic growth can be stable for a wide range of spacings below the point of minimum undercooling at low velocity, contrary to what is predicted by existing stability analyses. This overstabilization can be explained by relaxing Cahn's assumption that lamellae grow locally normal to the eutectic interface.

Dynamics of a faceted nematic-smectic-B front in thin-sample directional solidification

We present an experimental study of the directional-solidification patterns of a nematic-smectic-B front. The chosen system is C4H9-(C6H10)2CN (in short, CCH4) in 12 microm-thick samples, and in the planar configuration (director parallel to the plane of the sample). The nematic-smectic-B interface presents a facet in one direction-the direction parallel to the smectic layers--and is otherwise rough and devoid of forbidden directions. We measure the Mullins-Sekerka instability threshold and establish the morphology diagram of the system as a function of the solidification rate V and the angle straight theta(0) between the facet and the isotherms. We focus on the phenomena occurring immediately above the instability threshold when straight theta(0) is neither very small nor close to 90 degrees. Under these conditions, we observe drifting shallow cells and a type of solitary wave, called "faceton," which consists essentially of an isolated macroscopic facet traveling laterally at such a velocity that its growth rate with respect to the liquid is small. Facetons may propagate either in a stationary or an oscillatory way. The detailed study of their dynamics casts light on the microscopic growth mechanisms of the facets in this system.

Novel malonamide derivatives as alpha v beta 3 antagonists. Syntheses and evaluation of 3-(3-indolin-1-yl-3-oxopropanoyl)aminopropanoic acids on vitronectin interaction with alpha v beta 3

In attempt to find novel integrin alphavbeta3 antagonists, we selected SC65811 and its guanidine analogue (1) as lead compounds. Modification of the glycine part of SC65811 led to a new series of malonamide derivatives that exhibited alphavbeta3 inhibitory activity. Among them, (R,S)-3-[3-[6-(3-benzylureido)indolin-1-yl]-3-oxopropanoylamino]-3- (pyridin-3-yl)propanoic acid (43a) showed not only potent activity with an IC50 value of 3.0 nM but also good selectivity for alphavbeta3 relative to alphaIIbbeta3, alpha5beta1, and alphavbeta5 with IC50 values of 19,000, 11,000, and 14 nM, respectively. Furthermore, optimization of 43a led to the most potent alphavbeta3 antagonist, (R,S)-3-(3-[6-[(4,5-dihydro-1H-imidazol-2-yl)amino]indolin-1-yl]-3-oxopropanoylamino)-3-(quinolin-3-yl)propanoic acid (431) with an IC50 value of 0.42 nM. The synthesis and the structure-activity relationships of these malonamide derivatives are presented.

Involvement of p38 MAP kinase in TGF-beta-stimulated VEGF synthesis in aortic smooth muscle cells

Although it is known that transforming growth factor (TGF)-beta induces vascular endothelial growth factor (VEGF) synthesis in vascular smooth muscle cells, the underlying mechanisms are still poorly understood. In the present study, we examined whether the mitogen-activated protein (MAP) kinase superfamily is involved in TGF-beta-stimulated VEGF synthesis in aortic smooth muscle A10 cells. TGF-beta stimulated the phosphorylation of p42/p44 MAP kinase and p38 MAP kinase, but not that of SAPK (stress-activated protein kinase)/JNK (c-Jun N-terminal kinase). The VEGF synthesis induced by TGF-beta was not affected by PD98059 or U0126, specific inhibitors of the upstream kinase that activates p42/p44 MAP kinase. We confirmed that PD98059 or U0126 did actually suppress the phosphorylation of p42/p44 MAP kinase by TGF-beta in our preparations. PD169316 and SB203580, specific inhibitors of p38 MAP kinase, significantly reduced the TGF-beta-stimulated synthesis of VEGF (each in a dose-dependent manner). PD169316 or SB203580 attenuated the TGF-beta-induced phosphorylation of p38 MAP kinase. These results strongly suggest that p38 MAP kinase plays a part in the pathway by which TGF-beta stimulates the synthesis of VEGF in aortic smooth muscle cells.

Dynamic properties influence the perception of facial expressions

Two experiments were conducted to investigate the role played by dynamic information in identifying facial expressions of emotion. Dynamic expression sequences were created by generating and displaying morph sequences which changed the face from neutral to a peak expression in different numbers of intervening intermediate stages, to create fast (6 frames), medium (26 frames), and slow (101 frames) sequences. In experiment 1, participants were asked to describe what the person shown in each sequence was feeling. Sadness was more accurately identified when slow sequences were shown. Happiness, and to some extent surprise, was better from faster sequences, while anger was most accurately detected from the sequences of medium pace. In experiment 2 we used an intensity-rating task and static images as well as dynamic ones to examine whether effects were due to total time of the displays or to the speed of sequence. Accuracies of expression judgments were derived from the rated intensities and the results were similar to those of experiment 1 for angry and sad expressions (surprised and happy were close to ceiling). Moreover, the effect of display time was found only for dynamic expressions and not for static ones, suggesting that it was speed, not time, which was responsible for these effects. These results suggest that representations of basic expressions of emotion encode information about dynamic as well as static properties.

Attractiveness of facial averageness and symmetry in non-western cultures: in search of biologically based standards of beauty

Averageness and symmetry are attractive in Western faces and are good candidates for biologically based standards of beauty. A hallmark of such standards is that they are shared across cultures. We examined whether facial averageness and symmetry are attractive in non-Western cultures. Increasing the averageness of individual faces, by warping those faces towards an averaged composite of the same race and sex, increased the attractiveness of both Chinese (experiment 1) and Japanese (experiment 2) faces, for Chinese and Japanese participants, respectively. Decreasing averageness by moving the faces away from an average shape decreased attractiveness. We also manipulated the symmetry of Japanese faces by blending each original face with its mirror image to create perfectly symmetric versions. Japanese raters preferred the perfectly symmetric versions to the original faces (experiment 2). These findings show that preferences for facial averageness and symmetry are not restricted to Western cultures, consistent with the view that they are biologically based. Interestingly, it made little difference whether averageness was manipulated by using own-race or other-race averaged composites and there was no preference for own-race averaged composites over other-race or mixed-race composites (experiment 1). We discuss the implications of these results for understanding what makes average faces attractive. We also discuss some limitations of our studies, and consider other lines of converging evidence that may help determine whether preferences for average and symmetric faces are biologically based.

Trehalose suppresses lipopolysaccharide-induced osteoclastogenesis bone marrow in mice

We have previously shown that trehalose suppresses bone loss in ovariectomized (OVX) mice by way of inhibiting osteoclast differentiation in bone marrow. Also, trehalose inhibits the secretion of interleukin-6 in bone marrow cell cultures, resulting in a decrease in osteoclast formation. In this study, we examined the effect of trehalose on osteoclastogenesis using another model of bone resorption, namely lipopolysaccharide (LPS)-stimulated osteoclast induction. Mice were given trehalose (1g/kg) by gastric intubation for 5 consecutive days, and 24 hours later, 14 mg/kg of LPS was injected intraperitoneally. Trehalose significantly suppressed LPS-induced tumor necrosis factor (TNF)-alpha production after 90 min and decreased the number of osteoclasts in the bone marrow 48 hours after LPS injection. These results indicate that trehalose suppresses excessive osteoclastogenesis not only in OVX mice but also in a LPS-induced bone resorption mouse model and further suggest that the latter finding may be mediated at least in part through a decrease in TNF-alpha production.

A principal component analysis of facial expressions

Pictures of facial expressions from the Ekman and Friesen set (Ekman, P., Friesen, W. V., (1976). Pictures of facial affect. Palo Alto, California: Consulting Psychologists Press) were submitted to a principal component analysis (PCA) of their pixel intensities. The output of the PCA was submitted to a series of linear discriminant analyses which revealed three principal findings: (1) a PCA-based system can support facial expression recognition, (2) continuous two-dimensional models of emotion (e.g. Russell, J. A. (1980). A circumplex model of affect. Journal of Personality and Social Psychology, 39, 1161-1178) are reflected in the statistical structure of the Ekman and Friesen facial expressions, and (3) components for coding facial expression information are largely different to components for facial identity information. The implications for models of face processing are discussed.

A new method for assaying adhesion of cancer cells to the greater omentum and its application for evaluating anti-adhesion activities of chemically synthesized oligosaccharides

A new ex vivo method for assaying adhesion of cancer cells to the greater omentum has been developed using mouse greater omentum and [3H]labelled human gastric and mouse colorectal cancer cells. Since the adhesion rates were found to increase up to 18 h and labelled cells seemed to be stable during the period, the present method could be useful for investigating adhesion of cancer cells to the greater omentum, which must occur at the first step of the peritoneal dissemination. The adhesion of cancer cells to the greater omentum was inhibited by a series of chemically synthesized oligosaccharides and Gal beta1,3[3OMeGal beta1,4GlcNAc beta1,6]alphaBn was found to be the best inhibitor. The anti-tumor effect of this novel tetrasaccharide in vivo was shown in preliminary experiments using Balb/c mice and colon26 cells.

Altered expression of genes in experimentally induced myopic chick eyes

PURPOSE

To identify a casual pathway between the alteration in visual experience, due to form deprivation and hyperopic defocus, and the increase in eye growth, we searched for candidate genes having regulatory effects on eye growth under myopic conditions.

METHODS

The expression of the brain-derived neurotrophic factor, neurotrophin-3, sonic hedgehog, nerve growth factor, Six-3 and the Lh-2 group of genes in the transcriptional level after experimentally induced myopia (form-deprivation by goggles and by hyperopic defocus using negative spectacle lenses) were evaluated by semiquantitative reverse transcriptional polymerase chain reaction and Northern blot analysis.

RESULTS

Results showed that only the sonic hedgehog gene was differentially expressed in the experimentally induced myopic retinal samples compared with controls.

CONCLUSIONS

The sonic hedgehog gene may have regulatory functions in the signaling of the cascade of events that leads to axial elongation and vitreous enlargement of the eye under myopic conditions.

Magnitude of the regression to the mean within one-year intra-individual changes in serum lipid levels among Japanese male workers

To investigate the magnitude of the 'regression to the mean' effect for the changes in serum total cholesterol (TC), triglycerides (TG), and high density lipoprotein cholesterol (HDLC) levels during one-year interval between annual health check-ups in occupational settings, the relationships between the baseline level and subsequent one-year change in TC, TG or HDLC were analyzed using paired health check-up data in 1998 and 1999 of 547 Japanese male clerical workers. After adjustment for age, body mass index (BMI), yearly change in BMI, drinking score and smoking score by the multivariate analyses, the yearly changes in each serum lipid (deltaTC, deltaLn(TG) or deltaHDLC) were clearly inversely associated with the lipid levels in 1998. For example, in the multiple linear regression analyses setting delta value in each serum lipid as a dependent variable, the partial regression coefficients for the baseline lipid levels (beta1) were - 0.21 (p<0.001) for the TC, -0.39 (p<0.001) for the Ln(TG) and -0.15 (p<0.001) for the HDLC, respectively. These results suggest that the observed yearly change in each serum lipid level may largely reflect the 'regression to the mean' effect in addition to the real yearly biological change.

On-site diagnosis of H. pylori infection by urine

We have recently developed an on-site diagnostic kit for H. pylori infection using urine (utilizing immunochromatographic method employing a nitrocellulose membrane coated by extracted H. pylori antigen). Accordingly, we investigated its usefulness in 155 consecutive dyspeptic patients using the 13C urea breath test as a gold standard and further compared its performance with two commercially available rapid diagnostic kits that use whole blood (Helisal Rapid Blood, and ImmunoCard H. pylori). As the results, the urine based on-site diagnostic kit provided 95.9% sensitivity and 87.9% specificity with 92.9% accuracy, which were comparable or even better than that of both rapid whole blood tests, suggesting its usefulness in screening of H. pylori infection.

Incidental learning of real-world regularities

The large literature on incidental learning relies almost exclusively on laboratory experiments. Whenever researchers have attempted to demonstrate incidental learning of real-world regularities, they have typically failed to show learning. For example, it is well established that people do not learn regularities in everyday objects, such as the left-right orientation of faces on coins, despite a very large exposure to them. In this report, we examine this apparent contradiction. We argue that most studies exploring real-life incidental learning use tests that are not as sensitive to low-confidence information as those traditionally used in laboratory tasks. Using more sensitive measures, we show that it is possible to learn regularities from British and Japanese cultural life as a direct result of exposure to these regularities. Further, confidence measures suggest that although the information may be acquired incidentally, it can be expressed with and without concomitant awareness of that knowledge.

The Noh mask effect: vertical viewpoint dependence of facial expression perception

Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences.

Enhancement by sphingosine 1-phosphate in vasopressin-induced phosphoinositide hydrolysis in aortic smooth-muscle cells: involvement of p38 MAP kinase

We previously reported that sphingosine 1-phosphate (S-1-P), a sphingomyelin metabolite, activates p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase in aortic smooth-muscle A10 cells. In the present study, we investigated the effect of sphingomyelin metabolites on phospholipase C-catalyzing phosphoinositide hydrolysis induced by arginine vasopressin (AVP) in A10 cells. C(2)-ceramide and sphingosine had little effect on inositol phosphate (IP) formation stimulated by AVP. S-1-P, which alone slightly stimulated the IPs formation, dose-dependently amplified the AVP-induced formation of IPs. Tumor necrosis factor-alpha enhanced the AVP-induced formation of IPs. However, S-1-P did not enhance the formation of IPs by NaF, a heterotrimeric GTP-binding protein activator. Pertussis toxin inhibited the effect of S-1-P. PD98059, an inhibitor of the upstream kinase that activates p44/p42 MAP kinase, had little effect on the enhancement by S-1-P. SB203580, an inhibitor of p38 MAP kinase, suppressed the effect of S-1-P on the formation of IPs by AVP. SB203580 inhibited the AVP-induced phosphorylation of p38 MAP kinase. Pertussis toxin suppressed the phosphorylation of p38 MAP kinase by S-1-P. These results indicate that S-1-P amplifies AVP-induced phosphoinositide hydrolysis by phospholipase C through p38 MAP kinase in vascular smooth-muscle cells.

Pentobarbital, but not propofol, suppresses vasopressin-stimulated heat shock protein 27 induction in aortic smooth muscle cells

BACKGROUND

Although it is known that systemic blood pressure decreases after the administration of pentobarbital or propofol, the mechanisms underlying the cardiovascular effects of these anesthetics are still poorly understood. The authors previously showed that vasopressin stimulates the induction of heat shock protein (HSP) 27, a low-molecular-weight HSP, by a protein kinase C-dependent manner in aortic smooth muscle A10 cells. It is recognized that HSP27 may act as a chaperone like high-molecular-weight HSPs such as HSP70. HSP27 is reportedly associated with agonist-induced contraction of vascular smooth muscle cells. The authors examined the effects of pentobarbital and propofol on the vasopressin-stimulated HSP27 induction in A10 cells.

METHODS

Cultured A10 cells were pretreated with pentobarbital or propofol and then stimulated by vasopressin or 12-o-tetradecanoylphorbol 13-acetate (TPA). The effect of vasopressin on HSP70 was evaluated by Western blot analysis and compared with its effect on HSP27. The concentrations of HSP27 were determined by a specific immunoassay. The effect of pentobarbital on the expression levels of mRNA for HSP27 by vasopressin was evaluated by Northern blot analysis.

RESULTS

Vasopressin induced HSP27 but had little effect on HSP70. At concentrations used clinically, pentobarbital inhibited the accumulation of HSP27 by vasopressin or TPA. Pentobarbital reduced the levels of mRNA for HSP27 induced by vasopressin. In contrast, propofol affected neither the vasopressin- nor TPA-induced HSP27 accumulation.

CONCLUSIONS

These results suggest that pentobarbital suppresses the vasopressin-stimulated HSP27 induction in vascular smooth muscle cells. This inhibitory effect is probably exerted at a point downstream from protein kinase C.

IL-18 prevents the development of chronic graft-versus-host disease in mice

The development of chronic graft-versus-host disease (GVHD), which is induced by the transfer of DBA/2 spleen cells into (C57BL/6 x DBA/2)F1 (BDF1) mice, is closely related to diminished donor anti-host CTL activity and host B cell hyperactivation. Therefore, an approach which activates donor CD8+ T cells or suppresses donor CD4+ T cell-host B cell interaction may have clinical utility in the treatment of chronic GVHD. We have previously demonstrated that IL-18 induces the development of naive CD8+ T cells into type I effector cells in DBA/2 anti-BDF1 MLC. In this paper we examined the effect of IL-18 administration on the development of chronic GVHD in mice. The treatment was started before or after the onset of clinical evidence of the disease. Regardless of the treatment schedule, IL-18 significantly decreased immunological parameters indicative of chronic GVHD, such as elevated serum IgG antinuclear Abs, IgG1, and IgE levels, and host B cell numbers and their activation. Importantly, IL-18-treated mice did not show the same acute GVHD-like symptoms reported for IL-12 treatment, because there was no weight loss, death, or severe immunodeficiency as indicated by a decrease in IL-2 and IFN-gamma production by Con A-stimulated spleen cells. In contrast, IL-18 treatment partially but significantly restored the production of these cytokines. Data further suggested that these IL-18-mediated therapeutic effects may be due to the induction of donor CD8+ CTL, the decrease in donor CD4+ T cell numbers, and a down-regulation of host B cell MHC class II expression. Thus, our results suggest that IL-18 has beneficial effects in the prevention and treatment of chronic GVHD.

Traveling waves, two-phase fingers, and eutectic colonies in thin-sample directional solidification of a ternary eutectic alloy

We present an experimental investigation of the morphological transition of lamellar eutectic growth fronts called "formation of eutectic colonies" by the method of thin-sample directional solidification of a transparent model alloy, CBr4-C2Cl6. This morphological transition is due to the presence in the melt of traces of chemical components other than those of the base binary alloy (impurities). In this study, we use naphthalene as an impurity. The formation of eutectic colonies has generally been viewed as an impurity-driven Mullins-Sekerka instability of the envelope of the lamellar front. This traditional view neglects the strong interaction existing between the Mullins-Sekerka process and the dynamics of the lamellar pattern. This investigation brings to light several original features of the formation of eutectic colonies, in particular, the emission of long-wavelength traveling waves, and the appearance of dendritelike structures called two-phase fingers, which are connected with this interaction. We study the part played by these phenomena in the transition to eutectic colonies as a function of the impurity concentration. Recent theoretical results on the linear stability of ternary lamellar eutectic fronts [Plapp and Karma, Phys. Rev. E 60, 6865 (1999)] shed light on some aspects of the observed phenomena.

Interleukin-18 in combination with IL-2 enhances natural killer cell activity without inducing large amounts of IFN-gamma in vivo

Interleukin-18 (IL-18) is known to synergistically enhance murine natural killer (NK) cell activity in vitro when combined with either IL-12 or IL-2. However, it has also been demonstrated that simultaneous administration of IL-18 and IL-12 to mice induces extraordinarily large amounts of interferon-gamma (IFN-gamma) in the serum. In this study, we examined the effects of a combination of IL-18 and IL-2 on in vivo NK cell activation in parallel with the induction of toxicity. In contrast to the IL-18 and IL-12 combination, the combined administration of IL-18 and IL-2 to BALB/c mice for 3 days induced neither high levels of IFN-gamma production nor other visible side effects. When compared with treatment with IL-18 or IL-2 alone, the combined treatment resulted in a significant increase in the number of DX-5 (pan-NK cells marker)-positive cells in spleens and a marked enhancement of splenic NK activity, as determined by standard cytotoxicity assays. Enhanced splenic cytotoxicity generated in the mice treated with both IL-18 and IL-2 was also observed against syngeneic Colon 26 adenocarcinoma cells. Consistent with this in vitro observation, combined treatment produced a significantly stronger inhibitory effect on the pulmonary metastases following i.v. injection of Colon 26 tumor cells than treatment with either cytokine alone. These results suggest that IL-18 combined with IL-2 potentiates in vivo NK cell activity and contributes to inhibition of tumor metastasis without inducing significant toxicity.

Effects of aldehyde dehydrogenase and acetyl-CoA synthetase on acetate formation in sake mash

To reveal the mechanism of the production of acetate by sake yeast (Saccharomyces cerevisiae), the expression of genes encoding aldehyde dehydrogenase (ALD), acetyl-CoA synthetase (ACS) and acetyl-CoA hydrolase (ACH), which are related to acetate production, was investigated. Northern blot analysis using total RNA of sake yeast isolated from sake mash revealed that all of the tested genes, ACS1, ACS2, ALD2/3, ALD4, ALD6 and ACH1, were transcribed during sake fermentation. Transcription of ALD2/3 was detected only in the early stage of sake fermentation. A static culture of sake yeast in hyperosmotic media including 1 M sorbitol or 20% glucose resulted in high acetate production and increased transcription of ALD2/3. This is the same result as reported in an aerobic condition, and induction of ALD2/3 seemed to be one reason for high acetate production at high glucose concentration during fermentation. Overexpression of ACS2 resulted in low acetate production both during small-scale sake fermentation and in a static liquid culture. On the other hand, over-expression of ACS1 did not change acetate productivity significantly in a static culture. These results indicate that ALD2/3 and ACS2 play important roles for acetate production during sake fermentation.

Molecular mechanisms of expression of Lewis b antigen and other type I Lewis antigens in human colorectal cancer

Lewis b (Leb) antigens are gradiently expressed from the proximal to the distal colon, i.e., they are abundantly expressed in the proximal colon, but only faintly in the distal colon. In the distal colon, they begin to increase at the adenoma stage of cancer development and then increase with cancer progression. We aimed to clarify the molecular basis of Leb antigen expression in correlation with the expression of other type I Lewis antigens, such as Lewis a (Lea) and sialylated Lewis a (sLea), in colon cancer cells. Considering the Se genotype and the relative activities of the H and Se enzymes, the amounts of Leb antigens were proved to be determined by both the H and Se enzymes in noncancerous and cancerous colon tissues. But the Se enzyme made a much greater contribution to determining the Lebamounts than the H enzyme. In noncancerous colons, the Se enzyme were gradiently expressed in good correlation with the Leb expression, while the H enzyme was constantly expressed throughout the whole colon. In distal colon cancers, the H and Se enzymes were both significantly upregulated in comparison with in adjacent noncancerous tissues. In proximal colon cancers, expression of the H enzyme alone was highly augmented. The augmented expression of Leb antigens in distal colon cancers is caused mainly by upregulation of the Se enzyme and partly by the H enzymes, while it is caused by upregulation of the H enzyme alone in proximal colon cancers. The Se gene dosage profoundly influences the amounts of the Leb, Lea, and sLea antigens in whole colon tissues, regardless of whether they are noncancerous or cancerous tissues. It suggests that the Se enzyme competes with alpha2,3 sialyltransferase(s) and the Le enzyme for the type I acceptor substrates.

[The use of noninvasive positive pressure ventilation in the early postoperative period after cardiovascular surgery]

We used noninvasive positive pressure ventilation (NPPV) in 7 ICU patients after cardiovascular surgery. In 6 patients, we measured the variables of hemodynamics and arterial oxygenation by application of this nasal respiratory support (Companion 320 I/E, Puritan Bennett). Ventilator settings of expiratory positive airway pressure (EPAP) 3 cmH2O and inspiratory positive airway pressure (IPAP) 10 cmH2O were used and continued for 30 minutes. There were no significant changes in any hemodynamic variables during NPPV. Arterial oxygenation also remained unchanged at 30 min after discontinuation of NPPV. To conclude the efficacy of NPPV after cardiovascular surgery, higher level of IPAP and the combination with postural drainage should be studied further.

Allopurinol, an inhibitor of xanthine oxidase, improves the development of IVM/IVF bovine embryos (>4 cell) in vitro under certain culture conditions

To determine the origin of free oxygen radicals in the culture medium of bovine embryos, the effect of allopurinol, an inhibitor of xanthine oxidase, on the development of embryos (>4 cell) in modified synthetic oviduct fluid (m-SOF) medium was examined. When embryos were cultured in the presence of 0.2 mM allopurinol under high oxygen tension (5% CO2 in air), the blastocyst rate significantly (P<0.05) increased compared with the absence of allopurinol (allopurinol (+) 42 vs. (-) 25%; Day 6, 63 vs. 51%; Day 7, 69 vs. 58%; Day 8). However, allopurinol had no effect on embryo development under low oxygen tension (5% CO2, 5% O2, 90% N2). Moreover, it was found that the developmental rate and the total cell number of blastocysts decreased (development rate: 60 vs. 28%, cell number: 132 vs. 74) when the embryos were cultured in medium containing 0.01 U/mL xanthine oxidase (XOD) and 0.1 mM hypoxanthine (HXT), and the damaging effect of XOD and HXT was removed by the addition of 0.2 mM allopurinol. The beneficial effect of allopurinol was also observed when the glucose concentration was increased to 4.5 mM from 1.5 mM (control: 22% vs. allopurinol: 34%; Day 8), but no beneficial effects were observed in the media without glucose (control: 55% vs. allopurinol: 59%). Taken together, these results suggested that a portion of the free oxygen radicals are generated from the XOD and HXT reactions under culture conditions, and this generation is enhanced by high oxygen tension in the gas atmosphere or by high glucose concentrations in the medium.

Pulmonary arterial and right ventricular responses to prophylactic albumin administration before aortic unclamping during abdominal aortic aneurysmectomy

During abdominal aortic aneurysmectomy (AAAectomy) and before aortic unclamping (XU), we studied the effects of albumin administration on pulmonary arterial and right ventricular responses in 39 anesthetized patients using a modified thermodilution technique. Group 1 patients (n = 18) were given no extra IV fluids. Group 2 patients (n = 21) were given additional albumin administration (5% albumin at 10 mL/kg) before XU. After XU, mean arterial blood pressure (MAP) decreased significantly in each group, and MAP and stroke volume index (SVI) were not significantly higher in Group 2 than in Group 1. At 5 min after XU, the patients in Group 2 had a higher mean pulmonary arterial pressure and pulmonary vascular resistance index and a lower right ventricular ejection fraction than those in Group 1 (P < 0.05), but their SVIs were well maintained. These results indicate that albumin administration before XU may not always prevent post-XU hypotension. It caused a significant increase in right ventricular afterload and a significant dilation of the right ventricular cavity; however, right ventricular function was almost equally maintained in both groups. However, because SVI did not increase in some patients (Group 2) with the increase in right ventricular end-diastolic volume index after XU, albumin administration should be performed carefully before XU during AAAectomy.

IMPLICATIONS

We studied the effects of albumin administration before aortic unclamping on pulmonary arterial and right ventricular responses during abdominal aortic aneurysmectomy using a modified thermodilution technique. Albumin administration before aortic unclamping may not always prevent hypotension, and it may cause a higher pulmonary arterial pressure than in patients without albumin administration.

[Hemorrhagic shock during laparoscopic cholecystectomy detected by transesophageal echocardiography]

A 47-year-old man was scheduled for laparoscopic cholecystectomy under general anesthesia supplemented with epidural anesthesia. A direct arterial line and a transesophageal echocardiogram probe were inserted before surgery. Anesthesia was maintained with nitrous oxide and isoflurane but without epidural anesthesia. Severe hypotension occurred about 30 minutes after introducing pneumoperitoneum but surgeons denied massive bleeding in the operative field. Although this made us difficult to diagnose the incident as massive bleeding or pulmonary air embolism (PAE), a collapsed heart was detected by transesophageal echocardiography (TEE). Its end-diastolic diameter of the left ventricle was reduced to 20 mm and left ventricular end-systolic cavity obliteration was demonstrated. We could easily diagnose the decrease of blood volume due to PAE using TEE.

[Difficult tracheal intubation with von Recklinghausen disease]

We experienced a case of difficult tracheal intubation in a 15-year-old boy with von Recklinghausen disease scheduled for resection of a right neck tumor. His scoliosis made it difficult to intubate and to manage airway because he easily developed dyspnea. We tried nasotracheal intubation with the patient awake under sedation using a bronchofiberscope, but we found an unexpected tumor jeopardizing his airway patency near his vocal cord. Preoperative examination of a tumor in the airway is essential in the anesthetic management of the patients with von Recklinghausen disease.

Effects of sexual dimorphism on facial attractiveness

Testosterone-dependent secondary sexual characteristics in males may signal immunological competence and are sexually selected for in several species. In humans, oestrogen-dependent characteristics of the female body correlate with health and reproductive fitness and are found attractive. Enhancing the sexual dimorphism of human faces should raise attractiveness by enhancing sex-hormone-related cues to youth and fertility in females, and to dominance and immunocompetence in males. Here we report the results of asking subjects to choose the most attractive faces from continua that enhanced or diminished differences between the average shape of female and male faces. As predicted, subjects preferred feminized to average shapes of a female face. This preference applied across UK and Japanese populations but was stronger for within-population judgements, which indicates that attractiveness cues are learned. Subjects preferred feminized to average or masculinized shapes of a male face. Enhancing masculine facial characteristics increased both perceived dominance and negative attributions (for example, coldness or dishonesty) relevant to relationships and paternal investment. These results indicate a selection pressure that limits sexual dimorphism and encourages neoteny in humans.

Effects of antioxidants on the development of bovine IVM/IVF embryos in various concentrations of glucose

This study was undertaken to determine the effects of glucose, antioxidants and different oxygen tensions on the development of bovine embryos cultured in modified synthetic oviduct fluid (m-SOF) medium. In vitro matured (IVM) and fertilized (IVF) oocytes were incubated for 48 h. Embryos reaching at least the 4-cell stage were selected for further culture under various conditions for 6 d. Supplementing the m-SOF media with 4.5 mM glucose resulted in a significantly lower (P < 0.01) embryo developmental rate (21%; Day 8) than was obtained with 1.5 mM glucose (58%; Day 8) or no glucose (53%; Day 8). Antioxidants such as SOD, catalase and mannitol had no positive effect on embryo development in m-SOF medium supplemented with 1.5 mM glucose. However, in m-SOF medium supplemented with 4.5 mM glucose, SOD and mannitol significantly (P < 0.05) improved embryo development: SOD increased the developmental rate from 19 to 35% (Day 8), while mannitol increased it from 13 to 30% (Day 8). Low oxygen concentration improved embryo development significantly (P < 0.05) in m-SOF medium supplemented with 4.5 mM glucose (low O2: 31% vs high O2: 14%; Day 8) but not 0 mM glucose (low O2: 58% vs high O2: 55%; Day 8). Our data suggest that low concentration of glucose during culture of bovine embryos is beneficial, and that generation of free oxygen radicals is partly caused by a high concentration of glucose in the medium.

[Two elderly patients with thoracic herpetic pain and post herpetic neuralgia treated with continuous thoracic sympathetic ganglion block through a placed catheter]

Epidural block is very useful in the treatment of herpetic pain and post herpetic neuralgia. However, in the elderly patients with cardiac disease or diabetes mellitus, severe cardiovascular changes may occur by epidural block. Epidural block caused severe hypotension in two elderly patients with herpetic pain and post herpetic neuralgia who had diabetes mellitus or hypertension. Continuous thoracic sympathetic ganglion block with local anesthetics through a placed catheter reduced their pain and caused almost no changes in cardiovascular system.

Gabor-based Coding and Facial Similarity Perception

Little is known about how facial representation in the face-selective areas of inferotemporal cortex is built up from the output of earlier visual areas such as primary visual cortex (area V1). We report work on a model of perceived facial similarity based on topographically ordered aggregates of localised, oriented, and spatial-frequency-selective receptive fields characteristic of V1 cells. The receptive fields are approximated with a set of Gabor filters. This Gabor-based code allows representation of the fine differences in texture and configuration needed for facial discrimination processes. Lyons and Morikawa (1996 Investigative Ophthalmology and Visual Science37 910), showed that Gabor-based similarity is a good predictor of facial similarity for comparisons of fairly similar faces but not sufficient to model experience-dependent effects such as the ‘other race effect’.

Here we report results of a study on the effects of image negation on facial similarity perception. Negation of image gray levels interferes with face recognition (Bruce and Lanton, 1994 Perception23 803 – 822) while preserving 2-D facial-shape information. The Gabor similarity measure models non-endstopped complex cells of V1 and is not affected by image negation. One group of subjects judged similarity among a set of normal gray-scale facial images while another group judged similarity between negative images of the same stimuli. Agreement between the model and human subjects did not decrease with image negation. Moreover, human similarity ratings between negative faces were strongly correlated with those between positives. These results support Gabor-based similarity as a model for facial similarity perception.

Horizontal and Vertical Composite Effects in Novel Faces

The composite effect, where the recognition of the upper half of a face is disrupted by a discrepant lower half relative to an isolated half-face, without a corresponding effect for vertical half-faces, provides a ready method of investigating configural information in face recognition. In previous studies purely photographic techniques have been used for composite construction. We investigated the effects of more face-like stimuli, constructed by morphing techniques.

Subjects were trained to identify frontal Japanese faces, and tested on recognition on marked upper, lower, left, and right halves, both as half-faces and with distractors. While response accuracy for the upper and lower composites was lower than those for the relevant halves, there was no such effect for the right - left composites. A familiarity design was used in the second experiment to replicate this result. In the third experiment quarter-faces (top left - bottom right facial quadrants) were used to control for the information present. We found a strong composite effect for the right - left composites, and weaker ones for the top - bottom and quarter composites. In the fourth experiment we examined whether this effect was dependent on the presence of the quarter-composites by presenting them in a second block but found no effect of this manipulation.

It thus appears that although there is a composite effect with faces composed in a shape-free manner, this effect is unstable. Under certain circumstances subjects may convert from a top - bottom relational processing strategy to a right - left strategy. The information used, even with a constant task, is dependent upon the variability of the images involved.