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We can grasp various features of the outside world using summary statistics efficiently. Among these statistics, variance is an index of information homogeneity or reliability. Previous research has shown that visual variance information in the context of spatial integration is encoded directly as a unique feature, and currently perceived variance can be distorted by that of the preceding stimuli. In this study, we focused on variance perception in temporal integration. We investigated whether any variance aftereffects occurred in visual size and auditory pitch. Furthermore, to examine the mechanism of cross-modal variance perception, we also investigated whether variance aftereffects occur between different modalities. Four experimental conditions (a combination of sensory modalities of adaptor and test: visual-to-visual, visual-to-auditory, auditory-to-auditory, and auditory-to-visual) were conducted. Participants observed a sequence of visual or auditory stimuli perturbed in size or pitch with certain variance and performed a variance classification task before and after the variance adaptation phase. We found that in visual size, within modality adaptation to small or large variance, resulted in a variance aftereffect, indicating that variance judgments are biased in the direction away from that of the adapting stimulus. In auditory pitch, within modality adaptation to small variance caused variance aftereffect. For cross-modal combinations, adaptation to small variance in visual size resulted in variance aftereffect. However, the effect was weak, and variance aftereffect did not occur in other conditions. These findings indicate that the variance information of sequentially presented stimuli is encoded independently in visual and auditory domains.

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The supernumerary robotic limb system expands the motor function of human users by adding extra artificially designed limbs. It is important for us to embody the system as if it is a part of one's own body and to maintain cognitive transparency in which the cognitive load is suppressed. Embodiment studies have been conducted with an expansion of bodily functions through a "substitution" and "extension". However, there have been few studies on the "addition" of supernumerary body parts. In this study, we developed a supernumerary robotic limb system that operates in a virtual environment, and then evaluated whether the extra limb can be regarded as a part of one's own body using a questionnaire and whether the perception of peripersonal space changes with a visuotactile crossmodal congruency task. We found that the participants can embody the extra-limbs after using the supernumerary robotic limb system. We also found a positive correlation between the perceptual change in the crossmodal congruency task and the subjective feeling that the number of one's arms had increased (supernumerary limb sensation). These results suggest that the addition of an extra body part may cause the participants to feel that they had acquired a new body part that differs from their original body part through a functional expansion.

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Visual perspective taking is inferring how the world looks to another person. To clarify this process, we investigated whether employing a humanoid avatar as the viewpoint would facilitate an imagined perspective shift in a virtual environment, and which factor of the avatar is effective for the facilitation effect. We used a task that involved reporting how an object looks by a simple direction judgment, either from the avatar's position or from the position of an empty chair. We found that the humanoid avatar's presence improved task performance. Furthermore, the avatar's facilitation effect was observed only when the avatar was facing the visual stimulus to be judged; performance was worse when it faced backwards than when there was only an empty chair facing forwards. This suggests that the avatar does not simply attract spatial attention, but the posture of the avatar is crucial for the facilitation effect. In addition, when the directions of the head and the torso were opposite (i.e., an impossible posture), the avatar's facilitation effect disappeared. Thus, visual perspective taking might not be facilitated by the avatar when its posture is biomechanically impossible because we cannot embody it. Finally, even when the avatar's head of the possible posture was covered with a bucket, the facilitation effect was found with the forward-facing avatar rather than the backward-facing avatar. That is, the head/gaze direction cue, or presumably the belief that the visual stimulus to be judged can be seen by the avatar, was not required. These results suggest that explicit perspective taking is facilitated by embodiment towards humanoid avatars.

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To overcome limitations in perceptual bandwidth, humans condense various features of the environment into summary statistics. Variance constitutes indices that represent diversity within categories and also the reliability of the information regarding that diversity. Studies have shown that humans can efficiently perceive variance for visual stimuli; however, to enhance perception of environments, information about the external world can be obtained from multisensory modalities and integrated. Consequently, this study investigates, through two experiments, whether the precision of variance perception improves when visual information (size) and corresponding auditory information (pitch) are integrated. In Experiment 1, we measured the correspondence between visual size and auditory pitch for each participant by using adjustment measurements. The results showed a linear relationship between size and pitch-that is, the higher the pitch, the smaller the corresponding circle. In Experiment 2, sequences of visual stimuli were presented both with and without linked auditory tones, and the precision of perceived variance in size was measured. We consequently found that synchronized presentation of audio and visual stimuli that have the same variance improves the precision of perceived variance in size when compared with visual-only presentation. This suggests that audiovisual information may be automatically integrated in variance perception.

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Several studies have shown that our visual system may construct a "summary statistical representation" over groups of visual objects. Although there is a general understanding that human observers can accurately represent sets of a variety of features, many questions on how summary statistics, such as an average, are computed remain unanswered. This study investigated sampling properties of visual information used by human observers to extract two types of summary statistics of item sets, average and variance. We presented three models of ideal observers to extract the summary statistics: a global sampling model without sampling noise, global sampling model with sampling noise, and limited sampling model. We compared the performance of an ideal observer of each model with that of human observers using statistical efficiency analysis. Results suggest that summary statistics of items in a set may be computed without representing individual items, which makes it possible to discard the limited sampling account. Moreover, the extraction of summary statistics may not necessarily require the representation of individual objects with focused attention when the sets of items are larger than 4.

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The responses of an information-processing system such as a computer contain noise. As this noise increases, the system becomes uncontrollable and the operator may be exposed to a significant risk. In this study, we investigated whether operators' ability to perceive operation-response noise influenced the decision-to stop the operation of the system under the condition in which the operation system became gradually uncontrollable. In Experiment 1, we examined the correlation between operators' ability to discriminate the variance of operation-response noise and their performance in the stop-operation decision-making task. In Experiment 2, we trained a group of operators in variance discrimination task, and investigated the training effect on the performance in the stop-operation decision-making task. We demonstrated that the higher the operator's ability to discriminate variane, the earlier they decide to stop the system operation. However, the ability to discriminate influence to other indices of this decision-making. These results indicate that sensitive perception of operation-response noise causes th earlier stop operation, but it is not sufficient to lead to optimal decision-making in this regard.

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OBJECTIVE: We performed a detailed molecular analysis of bikunin-mediated anti-inflammation (suppressive effect of cytokine release, MAP kinase activation, and nuclear translocation of NF-kB) using a truncated form of bikunin. MATERIALS AND METHODS: We obtained bikunin derivatives that contained O-glycoside-linked N-terminal glycopeptide (Bik-m1), N-glycoside-linked C-terminal tandem Kunitz domains (Bik-m2), bikunin lacking O-glycoside (Bik-c), asialo bikunin (Bik-a), bikunin lacking N-glycoside (Bik-n), and purified C-terminal Kunitz domain II (kII) of bikunin (HI-8). Enzyme-linked immunosorbent assay and Western blot were carried out to measure secreted TNF-alpha and MAP kinase activation. RESULTS: We examined the TNF-alpha secretion in control and lipopolysaccharide (LPS)-treated neutrophils and did not see any changes of its protein levels in the cells pretreated with Bik-m1, Bik-m2, Bik-c, or HI-8. In all of the derivatives tested, only the derivatives that lacked N-glycoside side chain showed a significant suppression of TNF-alpha secretion by LPS. Only a small (21 amino acids) deletion of the N-terminal portion of bikunin (which corresponds to Bik-m2) abolished its suppressing activity of TNF-alpha secretion, thus suggesting that the N-terminal 21 amino acids play a critical role in anti-inflammation. Bik-m1 alone failed to show anti-inflammatory response. Bikunin failed to inhibit ionomycin-induced phosphorylation of MAP kinases. CONCLUSION: These data allow us to conclude that the cytokine expression was inhibited only by the O-glycoside-linked core protein without the N-glycoside side chain. Our results also suggest a possible role of bikunin for receptor-dependent MAP kinase activation.

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A giant abdominal tumor can exert a mass effect on surrounding structures. We report here a 34-year-old single female who presented with an increased abdominal girth and was subsequently found to have a giant abdominal mass. Large volume aspiration (85 L) at a slow rate (1 L/min) was initially performed before surgical resection to prevent the development of severe clinical hypotension after large volume aspiration. The patient underwent left salpingo-oophorectomy. Histology revealed a serous cystadenoma of the ovary. Systemic hemodynamics were sequentially measured during the perioperative period. The patient is now well.

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BACKGROUND: Massive ovarian edema is a benign enlargement of the ovary caused by accumulation of fluid occurring mainly in young women. Most cases are thought to result from venous and lymphatic obstruction. CASE REPORT: We treated a 40-year-old multiparous pregnant woman with massive ovarian edema who had been received clomiphene citrate. She was admitted at 13th week of pregnancy for acute pelvic pain. Left oophorectomy was performed, and pathologic examination disclosed massive ovarian edema. Our report is the first case of massive ovarian edema with pregnancy after ovulation induction using clomiphene citrate.

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BACKGROUND: The optimal upper limit of the normal range for CA125 in ovarian cancer screening is unknown. We investigated the prevalence of ovarian cancer among women in the Shizuoka Cohort Study on Ovarian Cancer Screening (SCSOCS) trial who had an abnormal ultrasound (US) and a CA125 level of 35 U/ml or less. METHODS: Of 48,027 women enrolled in the SCSOCS trial, 40,801 women never had a CA125 level of more than 35 U/ml, and underwent transvaginal US. RESULTS: Among the 40,801 women (age range 45-85 years), 4,859 women had an abnormal transvaginal US examination (category 1 [simple morphology], 4,741 women, and category 2 [complex morphology], 118 women). Of the 4,859 women, 981 (912 with the category 1 and 69 with the category 2) had a surgery. Of the 981 women, ovarian cancer was diagnosed in 8 (0.815%), and 5 of these 8 cancers (63%) were in stage I. The prevalence of ovarian cancer with abnormal US was 0.207% among women with a CA125 level of up to 15 U/ml, 0.488% among those with values of 15-20 U/ml, 0.685% among those with values of 20-25 U/ml, 2.04% among those with values of 25-30 U/ml, and 6.12% among those with values of 30-35 U/ml. CONCLUSIONS: Surgery-detected ovarian cancer is not rare among women with CA125 levels of 35 U/ml or less - levels generally thought to be in the normal range.

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OBJECTIVE: Our prospective studies in Japan have found an increased ovarian cancer incidence in women with ovarian endometrioma (standardized incidence ratio, 8.95; 95% confidence intervals, 4.12-5.3). The risk increased with increasing age at ovarian endometrioma diagnosis. The goal of this study was to define the risk factor(s) of ovarian cancer development in a Japanese population with ovarian endometrioma. We also analyzed whether the predisposition toward ovarian cancer is limited to endometrioid and clear cell carcinoma. STUDY DESIGN: A total of 6398 participants at 212 participating hospitals in Shizuoka, Japan, were enrolled in the Shizuoka Cohort Study on Endometriosis and Ovarian Cancer (SCSEOC) Trial, which had prospective and retrospective components. The follow-up period was up to 17 years (median, 12.8 years). The risks of development of ovarian cancer were assessed in 6398 women with ultrasonographically diagnosed ovarian endometriomas. Cox proportional-hazards regression function was used to estimate impact in terms of risk factors and possible development of ovarian cancer. RESULTS: The prospective study demonstrated that 46 (0.72%) of 6398 women developed histologically proven ovarian cancer and were operated upon during follow-up. Clear cell carcinoma (39%) and endometrioid adenocarcinoma (35%) were commonly observed among women with ovarian cancer. By multivariate analysis, tumor size > or =9 cm in diameter and postmenopausal women were independent predictive factors of patients with development of ovarian cancer. CONCLUSIONS: Some endometriosis lesions may predispose to clear cell and endometrioid ovarian cancers. Advancing age and the size of endometriomas were independent predictors of development of ovarian cancer among women with ovarian endometrioma.

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Preeclampsia is a hypertensive disorder that is unique to pregnancy. Magnesium (Mg2+) supplementation is a potential new therapy to ameliorate development of hypertension. The aim of this work was to compare the effects of Mg2+ supplementation on systolic blood pressure (SBP) in young and aged rats. Spontaneously hypertensive rats (SHR) were divided into young (6-week-old male, n = 10) and old (16-week-old male, n = 10) groups. Each group of rats comprised two subgroups made of a control subgroup fed with normal rat chow (0.2% Mg2+, n = 5) and a high Mg2+ subgroup nourished with a Mg2+ rich diet (0.8% Mg2+, n = 5). Age-matched Wistar-Kyoto rats (WKY) were also allocated into two groups. SBP was assessed weekly for 12 weeks indirectly by the tail-cuff method. SBP increased progressively in SHR-young rats after 7 weeks. This increase was greater in the control subgroup compared to high Mg2+ subgroup at 7 weeks (p < 0.05). No difference in the SBP was registered between old SHR subgroups. Mg2+ supplementation does not exert antihypertensive effects in the WKY rats. In conclusion, Mg2+ supplementation may provide beneficial effect in the developmental phase of hypertension but not in established hypertension.

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Herein is reported a case of late-onset pulmonary embolism following pelvic surgery, despite prophylactic measures in the perioperative period. Twenty-six days after hysterectomy and pelvic lymphadenectomy for endometrial carcinoma, an 83-year-old woman developed a pulmonary embolism. This was caused by pelvic lymphocyst, which, in turn, led to chronic compression of the right external iliac vein. This case strongly suggests that prolonged postoperative thromboembolic prophylaxis should be considered in elderly patients undergoing lymphocyst following pelvic surgery.

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Activated neutrophils contribute to the development of preterm delivery. Because of its ability to suppress inflammation, bikunin, a Kunitz-type protease inhibitor, is currently in clinical trials. To investigate the molecular mechanism of this inhibition, we analyzed the effect of bikunin on pro-inflammatory cytokine production and nuclear factor-kappaB (NF-kappaB) activation in mouse neutrophils stimulated by lipopolysaccharide (LPS), an inflammatory inducer. Here, we show that bikunin: (i) blocks LPS-induced secretion of pro-inflammatory cytokines, including TNF-alpha and IL-1beta, in a dose-dependent manner; (ii) has an inhibitory effect on cytokine production at a concentration of 0.2 microM, reaching 65% inhibition at the highest doses of bikunin tested (5 microM); (iii) has the suppressive capacity of ERK1/2 and p38 signaling pathways; and (iv) inhibited sequentially the LPS-induced phosphorylation of IkappaB-alpha, degradation of IkappaB-alpha, and nuclear translocation of NF-kappaB. When the MAPK data are analyzed, a significant decrease in phosphorylation is not seen at 0.2 microM bikunin but is at 1.0 microM dosing. Bikunin can inhibit LPS-induced neutrophil activation and cytokine release, although it is unlikely that it works primarily through the inhibition of MAPK phosphorylation. These data suggest that such effects are important in vivo and play a major contributory role in abrogation of neutrophil-mediated inflammatory responses, such as preterm delivery.

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