Effects of Functional Electrical Stimulation on Attention and Brain Activity in Healthy Participants Using Near-Infrared Spectroscopy: An Interventional Study

Background Involuntary limb activation using functional electrical stimulation (FES) can improve unilateral spatial neglect. However, the impact of FES on brain activity related to spatial attention remains unclear. Thus, in this study, we aimed to examine the effects of FES on spatial attention. Methodology In this interventional study, 13 healthy right-handed participants were asked to perform the Posner task for six minutes both before and after either FES or sham stimulation during each set, resulting in a total of two sets. FES was applied to the left forearm extensor muscles, with a frequency of 25 Hz, a pulse width of 100 μs, and the intensity adjusted to reach the motor threshold. Both the energization and pause times were set to five seconds. The Posner task was used to measure reaction time to a target appearing on a computer screen. Brain activity, indicated by oxygenated hemoglobin values, was measured using near-infrared spectroscopy with 24 probes according to the International 10-20 system method. Results In the left hemisphere, oxygenated hemoglobin values in the premotor and supplementary motor areas, primary somatosensory cortex, and somatosensory association areas were significantly higher after FES than after sham stimulation. In the right hemisphere, oxygenated hemoglobin values were significantly increased in the premotor, primary, and supplementary motor areas; in the supramarginal gyrus; and in the somatosensory association areas after FES. Reaction times in the Posner task did not differ significantly between the FES and sham conditions. Conclusions Collectively, these results suggest that FES of the upper limbs can activate the ventral pathway of the visual attention network and improve stimulus-driven attention. Activation of stimulus-driven attentional function could potentially contribute to symptom improvement in patients with unilateral spatial neglect.

Effect of stimulation-driven attention in virtual reality balloon search training of patients with left unilateral spatial neglect after stroke: A randomized crossover study

Patients with unilateral spatial neglect (USN) commonly experiences stimulus-driven attention deficit characterized by unexpected stimuli detection. We investigated whether virtual reality (VR) balloon search training with the screen background shifted to left space could improve stimulus-driven attention in patients with USN. The participants were divided into two groups: immediate VR group (n = 14) and delayed VR group (n = 14). The immediate VR group first received VR balloon search training, followed by control training, for two weeks each. Delayed VR group received the same training in reverse order. Outcomes were changes in scores on Catherine Bergego Scale (CBS) and reaction time on the modified Posner task (MPT). There was significant improvement in CBS score change after VR balloon retrieval training (all F > 2.71; P < 0.002). In the invalid condition of MPT, significant improvements were shown after VR balloon search training in left-sided reaction time (improvement of stimulation-driven attention). This study shows that VR balloon search training can improve neglect symptoms by using an intensive intervention lasting 2 weeks.

Functional Connectivity Pattern Using Resting-state fMRI as an Assessment Tool for Spatial Neglect during the Recovery Stage of Stroke: A Pilot Study

PURPOSE

To determine if functional connectivity measured with resting-state functional MRI could be used as a tool to assess unilateral spatial neglect during stroke recovery.

METHODS

Resting-state functional MRI was performed on 13 stroke patients with lesions in the right cerebral hemisphere and 31 healthy subjects. The functional connectivity score was defined as a correlation of a target region with the right inferior parietal lobule. Spatial neglect was measured with a behavioral inattention test.

RESULTS

First, the functional connectivity scores between the right inferior parietal lobule and right inferior frontal gyrus, including the opercular and triangular parts, were significantly decreased in stroke patients with unilateral spatial neglect compared with patients without unilateral spatial neglect and were significantly correlated with the behavioral inattention test score. Second, the functional connectivity scores between the bilateral inferior parietal lobules were also significantly decreased in patients with unilateral spatial neglect compared with patients without unilateral spatial neglect and were significantly correlated with the behavioral inattention test score. Third, negative functional connectivity scores between the right inferior parietal lobule and bilateral medial orbitofrontal cortexes, which are related to the default mode network, were detected in patients without unilateral spatial neglect in contrast to a reduction of this negative tendency in patients with unilateral spatial neglect. The functional connectivity scores between these regions were significantly different between patients with and without unilateral spatial neglect and were negatively correlated with the behavioral inattention test score.

CONCLUSION

Though still in the pilot research stage and using a small number of cases, our findings are consistent with the hypothesis that functional connectivity maps generated with resting-state functional MRI may be used as a tool to evaluate unilateral spatial neglect during stroke recovery.

Effects of visual-motor illusions with different visual stimuli on the sit-to-stand of people with hemiplegia following stroke: A randomized crossover controlled trial

BACKGROUND

The objective of this study was to determine the effects of different visual stimuli during visual-motor illusion on sit-to-stand in people with hemiplegia following stroke.

METHODS

This was a randomized crossover controlled trial. Twenty people with hemiplegia following stroke were randomly divided into groups. The video images used for visual-motor illusion were ankle dorsiflexion without resistance (standard visual-motor illusion [standard illusion]) and maximum effort dorsiflexion with resistance (power visual-motor illusion [power illusion]). People with hemiplegia following stroke underwent both illusion interventions with a 1-week washout period in between; group A started with the standard illusion intervention and group B started with the power illusion intervention. Outcomes included the sit-to-stand duration, maximum weight-bearing value, trunk movement during sit-to-stand, ankle joint movement during sit-to-stand, and active ankle dorsiflexion movement on the paralyzed side.

RESULTS

The angular velocity of the trunk and ankle joints increased significantly during sit-to-stand, and sit-to-stand duration decreased significantly in response only to power illusion. In addition, the change in angular velocity of active ankle dorsiflexion was significantly greater in response to power illusion than was the change in response to standard illusion.

CONCLUSION

Power illusion induces a greater improvement in paralyzed ankle dorsiflexion function than standard illusion, resulting in shorter sit-to-stand duration.

The Effect of Trunk Position on Attentional Disengagement in Unilateral Spatial Neglect

Unilateral spatial neglect (USN) causes difficulties in disengaging attention from the right side to unexpected targets on the left. However, the relationship between egocentric spatial position and attentional disengagement remains unclear. Therefore, this study aimed to clarify the relationship between trunk position and attentional disengagement. Thirty-eight patients with early stroke onset were classified as follows: USN (n = 18), right brain damage without USN (n = 10), and left brain damage (n = 10). The primary outcome was reaction time (RT) in the modified Posner task (MPT). The MPT comprised a condition in which the preceding cue and target direction were the same (valid condition) and a condition in which the directions were opposite (invalid condition). RT to the target was calculated. The MPT was performed in three different trunk positions (trunk midline, left, and right). In each group, the RT was compared on the basis of the stimulus conditions and trunk position. The RT was delayed in the valid and invalid left conditions, especially in the invalid left condition. The RT of the trunk right condition was significantly reduced compared with that of trunk midline and left conditions in the invalid left condition. Thus, trunk position influences attentional disengagement. This study contributes to the rehabilitation of patients with neglect symptoms.

Effects of standing and walking training using a laser pointer based on stimulus-driven attention for behavioural outcome in spatial neglect: A single-case study

The therapy for unilateral spatial neglect (USN) is unclear. This case report investigated the effect of standing and walking training using a laser pointer based on stimulus-driven attention for USN. The patient was a right-handed 79-year-old man with cardiogenic cerebral embolism in the right middle and posterior cerebral arteries. Initially, we evaluated the absence of hemiparalysis in the lower limb and sensory disorder; almost all daily activities were performed independently. Intervention effects were verified using the BABA method. The course of the four phases (B1, A1, B2, A2) was conducted for 5 days. In the B1 and B2 phases, standing and walking training using a laser pointer was performed additionally to conventional physical therapy. Outcomes were measured using the Behavioural Inattention Test conventional subtest (BIT-c), Catherine Bergego Scale (CBS), and modified Posner task (MPT). The BIT-c remained unchanged in each phase. CBS scores improved after B1 and B2. In the MPT, the reaction time in the left space reduced after B1 and B2 compared with those in the A1 and A2 control phases. In this case, training may have contributed to the improvement in the response to the neglected space and behavioural assessment of USN.

Effects and Adaptation of Visual-Motor Illusion Using Different Visual Stimuli on Improving Ankle Joint Paralysis of Stroke Survivors—A Randomized Crossover Controlled Trial

Visual-motor illusion (VMI) is an intervention to induce kinesthetic sensation from visual stimuli. We aimed to compare the effects of VMI of different visual stimuli on the paralyzed side ankle joint of stroke hemiplegic patients (hemiplegic patients) and to clarify their indication. We applied two types of VMI images of ankle dorsiflexion: ankle dorsiflexion without resistance (standard VMI (S-VMI)) and maximum effort dorsiflexion with resistance (power VMI (P-VMI)). Twenty-two hemiplegic patients were divided into two groups: Group A, which received S-VMI first and P-VMI one week later (n = 11), and Group B, which received P-VMI first and S-VMI one week later (n = 11). Immediate effects were evaluated. Outcomes were the dorsiflexion angle and angular velocity, degree of sense of agency (SoA), and sense of ownership. Patient’s characteristics of cognitive flexibility were assessed using the Trail making test-B (TMT-B). Fugl-Meyer assessment and the Composite-Spasticity-Scale were also assessed. P-VMI was significantly higher than S-VMI in SoA and dorsiflexion angular velocity. Additionally, the degree of improvement in dorsiflexion function with P-VMI was related to TMT-B and degree of muscle tone. Therefore, P-VMI improves ankle function in hemiplegic patients more than S-VMI but should be performed with cognitive flexibility and degree of muscle tone in mind.

Effects of visual-motor illusion in stroke hemiplegic patients with left-side personal neglect: A report of two cases

Personal neglect is the neglect of self-body space, which often occurs in patients with unilateral spatial neglect (USN), but lacks a dedicated rehabilitation. The purpose of this study was to investigate the effects of visual-motor illusion (VMI) on two-stroke hemiplegic patients with left-side personal neglect. Case 1 was a 53-year-old man diagnosed with a right lenticulostriate artery infarction. Case 2 was a 76-year-old woman diagnosed with a right middle cerebral artery infarction. USN symptoms were not observed in either patient in the desk USN assessment, but personal neglect and USN symptoms in daily life were observed in both patients. Intervention effects were verified using an ABA design, comprising a 5-day three-phase (A1, B, A2). In phase B, VMI was performed on the paralyzed upper limb for 10 min in addition to conventional physical therapy. Outcomes measures were the Fluff test, Catherine Bergego Scale (CBS), Fugl-Meyer Assessment (FMA), and Functional Independence Measure (FIM). In both patients, no improvements were noted in FMA, but improvements were observed in the Fluff test, CBS, and FIM in phase B; these effects were retained in phase A2. Therefore, VMI may have contributed to improvements in Personal neglect and USN symptoms in daily life.

Effects of kinesthetic illusion induced by visual stimulation on the ankle joint for sit-to-stand in a hemiparesis stroke patient: ABA' single-case design

[Purpose] The purpose of this study was to investigate the effect of kinesthetic illusion induced by visual stimulation to the paralyzed side ankle joint on the sit-to-stand of a hemiparesis stroke patient. [Participant and Methods] A 33-year-old male with left hemiparesis due to a right putamen hemorrhage participated. This study used the ABA’ single-case design. Phase A and A’ conducted only conventional physiotherapy. Phase B conducted kinesthetic illusion induced by visual stimulation and conventional physiotherapy. To create a kinesthetic illusion, a video image of the patient’s ankle joint dorsiflexion movement on the non-paralyzed side was inverted and placed on the patient’s paralyzed ankle. The patient observed this display for 5 min. We evaluated weight-bearing symmetry values during sit-to-stand, duration of sit-to-stand, trunk and ankle joint movement on the paralyzed side during sit-to-stand, active ankle dorsiflexion angle on the paralyzed side, and the composite spasticity score. [Results] The weight-bearing symmetry values, movement of the ankle dorsiflexion during sit-to-stand, active ankle dorsiflexion angle, and composite spasticity score were significantly improved in phase B as compared with phase A and the effect was sustained in phase A’. [Conclusion] Kinesthetic illusion induced by visual stimulation for a hemiparesis stroke patient affected the ankle dorsiflexion function, resulting in an improved asymmetry during sit-to-stand as assessed by weight-bearing symmetry values.

More than the half number of the severe CAD patients without features of metabolic syndrome had hyperlipoprotein(a)-emia

Background

It was reported that insulin suppresses apolipoprotein(a) synthesis in primary cultures of cynomolgus monkey hepatocytes (Neele DM. Diabetologia 1999). Therefore, there is a possibility that inverse association exists between lipoprotein(a); Lp(a) and metabolic syndrome (Mets) with insulin resistance/ hyperinsulinemia for the coronary atherosclerosis.

Purpose

The purpose is to examine the association between Lp(a) and Mets on the CAD patients.

Method

847 male subjects with angiographically demonstrated CAD were enrolled. The subjects were divided into the five groups according to the scored numbers by the counting of Mets components shown below (presence 1, absence 0); 1. BMI ≥25kg/m2, 2. comorbidity of hypertension, 3. triglyceride ≥150mg/dL and/or HDL cholesterol &lt;40mg/dL, 4. fasting plasma glucose ≥110mg/dL and/or comorbidity of diabetes mellitus (Group 0; without any Mets components, Group 4; with all Mets component). The insulin levels (μU/mL) and the prevalence of hyperLp(a)-emia (≥30 mg/dL) were compared between in Group 0 and in Group 4. The blood samples for laboratory tests were collected after an over night fast.

Result

As the scored numbers increased, the insulin levels increased (Group 0; 5.1 μU/mL versus Group 4; 11.4 μU/mL: p&lt;0.0001) and the prevalence of hyperlipoprotein(a)-emia decreased (Group 0; 41.6% versus Group 4; 21.4%: p&lt;0.01). The prevalence of hyperLp(a)-emia increased as the severity of coronary atherosclerosis aggravated (Figure 1; one vessel disease 21.5%, two vessel disease 27.0% three vessel disease 32.1%: one vessel disease versus three vessel disease p&lt;0.01). Especially to limited the three vessel disease subjects (Figure 2), the prevalence of hyperlipoprotein(a)-emia in Group 0 was markedly high (56.7%).

Conclusion

More than the half number of severe CAD patients without features of Mets had hyperLp(a)-emia.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Investigating the Characteristics of Covert Unilateral Spatial Neglect Using the Modified Posner Task: A Single-subject Design Study

Objectives:

Patients identified as asymptomatic for unilateral spatial neglect (USN) based on paper-and-pen tests nonetheless often collide with objects to their left while walking. This study aimed to investigate chronic USN in subjects who experienced collisions while walking.

Methods:

Two patients with chronic USN who experienced collisions while walking were evaluated using the Behavioral Inattention Test-conventional (BIT-c). Additionally, the modified Posner task (MPT) was used to evaluate the left and right reaction times. MPT targets randomly appeared either on the side indicated by the cue (valid condition) or on the opposite side (invalid condition). This study used an alternating treatments single-case design. The valid and invalid conditions of the MPT alternated rapidly and randomly to determine differences in reaction time. Statistical analysis compared left and right reaction times using a one-tailed randomization test to study valid and invalid conditions.

Results:

The total BIT-c score was in the normal range for both subjects, whereas MPT reaction times were higher on the left side than on the right side for the invalid condition. However, for the valid condition, only Case B had increased reaction times on the left side.

Conclusions:

The MPT valid condition evaluates voluntary attention, whereas the invalid condition evaluates the reorientation of attention. Consequently, for Case A, a left reorientation of attention deficit was observed, whereas, for Case B, left voluntary attention and left reorientation of attention deficits were observed. The MPT results revealed the characteristics of covert neglect signs. USN evaluation would benefit from additional research using MPT.

The inverse association between lipoprotein(a) levels and metabolic syndorome and its components on coronary artery disease patients

Purpose

Neele DM (Diabetologia 1999) showed that insulin suppressed apolipoprotein(a) synthesis by primary cultures of cynomolgus monkey hepatocytes. Therefore, there is a possibility that inverse association exists between lipoprotein(a) [Lp(a)] and metabolic syndorome (Mets) with insulin resistance/hyperinsulinemia for coronary atherosclerosis. Sung KC (Nutr Metab Cardiovasc Dis 2013) described the inverse association between Lp(a) levels and Mets and its components on an asian occupational cohort. And high levels of Lp(a) were associated with preclinical atherosclerosis, as evaluated by coronary calcium score with cardiac computed tomography. There is no similar examination on coronary artery disease (CAD) patients. The purpose is to examine similar considerations on CAD patients.

Method

610 subjects with angiographically demonstrated CAD were enrolled. The patients who receiving medication for dyslipidemia and Insulin administration were excluded. The blood samples for laboratory tests were collected after an over night fast. Subjects were divided into four groups according to quartiles of Lp(a) levels (mg/dL). Ranges of quartile groups of Lp(a) were Q1: &lt;9.0, Q2: 9.0–&lt;16.0, Q3: 16.0–&lt;30.0, Q4: ≥30.0.

Results

The inverse association Lp(a) levels and Mets and its component. The comparison of Q1 (bottom quartile) versus Q4 (top quartile) was shown below; the comorbidity rate of Mets 19.5% versus 8.0% (p&lt;0.01), BMI (kg/m2) 23.5 versus 22.7 (p&lt;0.05), trigyceride (mg/dL) 144.0 versus 107.5 (p&lt;0.0001), HDL cholesterol (mg/dL) 46.8 versus 50.7 (p&lt;0.05), the comorbidity rate of hypertension 60.4% versus 50.7% (p=0.084), glucose (mg/dL) 107.1 versus 100.6 (p&lt;0.05), insulin (μU/mL) 8.49 versus 5.85 (p&lt;0.0001), HOMA-R 2.26 versus 1.44 (p&lt;0.0001). The mean number of diseased coronary vessel was higher in the Q4 group (2.07) than in the Q1 group (1.87) (p&lt;0.05).

Conclusion

There was the inverse association between Lp(a) levels and Mets and its components on CAD patients. The robust association was found between Lp(a) levels and severity of coronary atherosclerosis despite this inverse correlation.

Funding Acknowledgement

Type of funding source: None

Improvement of treatment outcomes after implementation of comprehensive pharmaceutical care in breast cancer patients receiving everolimus and exemestane

Combination therapy with everolimus and an aromatase inhibitor such as exemestane is an effective treatment option for advanced or recurrent breast cancer. However, the therapy is often limited because of the occurrence of severe adverse events (AEs), including oral mucositis, interstitial lung disease, diarrhea, and rash. Therefore, early management of AEs is extremely important to obtain maximum treatment outcome. We investigated here the effects of comprehensive pharmaceutical care for prevention of severe AEs on patient's quality-of-life (QOL) and continuation of therapy. QOL was assessed every month based on the five-level version of EuroQol-5-Dimension (EQ-5D-5L). AEs were graded according to the Common Terminology Criteria for Adverse Events (ver 4.0). Implementation of comprehensive pharmaceutical care remarkably reduced the incidence of severe oral mucositis as compared with those without such interventions. EQ-5D-5L health states were almost constant during 6 months after intervention, ranging from 0.850 to 0.889. Median time to treatment failure (TTF) was significantly longer after intervention than before [224.0 days, 95% confidence interval (CI): 117-331 days versus 34 days, 21-47 days, hazard ratio (HR): 0.027, 95% CI: 0.005 - 0.154, p<0.001]. These findings suggest that our comprehensive pharmaceutical care is highly effective for enhancing treatment outcome by maintaining patient's QOL.

Bovine oocytes from early antral follicles grow to meiotic competence in vitro: effect of FSH and hypoxanthine

A large number of oocytes are contained in the mammalian ovary. A very small number of these oocytes grow to the final size, mature, and are ovulated. In the ovary there are more early antral follicles than late antral or preovulatory follicles, offering a large pool of oocytes for IVM and IVF if appropriate culture conditions could be devised. In the present study, early antral follicles containing oocytes 90 to 99 microm in diameter were isolated from bovine ovaries. Cumulus-oocyte complexes (COC) with pieces of parietal granulosa (COCG) were then dissected from the follicles. The COCGs were embedded in collagen gels and cultured in Medium 199 with 10% fetal calf serum (FCS) for 8 d. In Experiment 1, the effect of hypoxanthine and FSH on the growth of bovine oocytes was examined. When hypoxanthine (2 and 4 mM) and FSH (10 ng/ml) were added to the culture medium, the number of granulosa cell-enclosed oocytes increased significantly (P < 0.05). All of the oocytes surrounded by granulosa cells showed a normal morphology and were at the germinal vesicle stage, while 75 to 94% of the denuded oocytes were degenerated and had resumed meiosis. The mean diameter of the oocytes showing normal morphology was significantly higher than that measured before culture (P < 0.05). In Experiment 2, the maturational competence of in vitro-grown bovine oocytes was examined. Oocytes which were 90 to 99 microm in diameter before culture did not have meiotic competence. After being in a growth culture of 4 mM hypoxanthine- and 10 ng/ml FSH-supplemented medium for 7 or 11 d, granulosa cell-enclosed oocytes were recovered from the COCGs. No significant difference (P < 0.05) in the diameters of the oocytes was observed between 7 and 11 d of culture (7 d: 107.5 +/- 6.1 microm, n = 30; 11 d: 108.0 +/- 5.3 microm, n = 35). After a subsequent 24 h in a maturation free of hypoxanthine and FSH medium, only 17% of the oocytes cultured for 7 d underwent germinal vesicle breakdown. On the other hand, 89% of the oocytes cultured for 11 d underwent germinal vesicle breakdown, and 11% of the oocytes emitted the first polar body and reached metaphase II. These results demonstrate for the first time that bovine oocytes harvested from early antral follicles can grow, and acquire meiotic competence in vitro.

Orientational distribution of collagen fibers in cobra skin

The orientation and distribution of collagen fibers were studied in leather prepared from cobra skin using both the mechanical method and Osaki's microwave method. The degree of preferred collagen-fiber orientation was largest at the centre of the dorsum and decreased gradually from the dorsum to the abdomen. The collagen fibers were, on average, aligned parallel to the spinal column in the dorsum, and tended to be aligned equally in all directions in the abdomen. The skin expanded easily in the direction perpendicular to the direction of collagen-fiber orientation. These results indicate that it is difficult for the skin to expand or shrink in the cranial to caudal direction, whereas it is relatively easy for the skin to expand around the circumference of the body of the cobra. Collagen-fiber orientation therefore seems to be closely related to the functional motions of cobra skin during locomotion and when swallowing prey.

Multiple superconducting phases in new heavy fermion superconductor PrOs4Sb12

The superconducting gap structure of recently discovered heavy fermion superconductor PrOs4Sb12 was investigated by using thermal transport measurements in magnetic field rotated relative to the crystal axes. We demonstrate that a novel change in the symmetry of the superconducting gap function occurs deep inside the superconducting state, giving a clear indication of the presence of two distinct superconducting phases with twofold and fourfold symmetries. We infer that the gap functions in both phases have a point node singularity, in contrast to the familiar line node singularity observed in almost all unconventional superconductors.

Transfer of IkappaBalpha gene increase the sensitivity of paclitaxel mediated with caspase 3 activation in human lung cancer cell

In oncogenic therapies, apoptosis seems to be the important mechanism of deciding chemotherapy effect. NF-kappaB transcription factors are implicated in the control of cell proliferation and apoptosis. NF-kappaB is activated by chemotherapy and by irradiation, and this pathway has been shown to protect cells potently from their stimuli-induced apoptosis. Furthermore, inhibition of NF-kappaB leads to enhanced apoptosis in response to various stimuli. However, because the role of NF-kappaB as a modifier of the intrinsic chemosensitivity of cancer cells is less clear, we have studied the impact of IkappaBalpha (an inhibitor of NF-kappaB) on the chemosensitivity of human lung cancer cells. We used adenoviral vectors expressing human IkappaBalpha (AdIkappaBalpha) and investigated the effects of IkappaBalpha gene transfer in combination with 6 anticancer agents on a human pulmonary adenocarcinoma cell line, A549. Solutions containing anticancer agents at various concentrations were added followed by the addition of recombinant adenovirus solutions, and each IC50 was calculated based on the dose-response curves. The gene transfer of AdIkappaBalpha decreased IC50 from 12.0 to 2.2 nM on paclitaxel and increased IC50 from 0.27 to 16.0 microM on SM5887 compared with the transfer of control gene, AdLacZ. The IC50 did not change clearly on the other anticancer drugs. To investigate this molecular mechanism, we measured caspase 3 activity by the transfer of IkappaBalpha gene. On result, paclitaxel increased caspase 3 activity and SM5887 decreased the activity. These results indicate that the cell killing effect of anticancer drug is influenced by the inhibition of NF-kappaB activity and may, at least in part, depend on the regulation of caspase 3 activation. Adenovirus mediated IkappaBalpha gene transfer improve the anti-cancer effect of paclitaxel to lung cancer cells through the regulation of caspase 3 activation.

Orientation and distribution of collagen fibers in the sagittal plane of the human adult calcaneus

Human right calcaneus bone, consisting of hydroxyapatite and collagen fibers, was cut in the sagittal plane which was parallel to the long axes of the calcaneus bone and the human lower limb, into samples approximately 1.5 mm thick. The angular dependence of transmitted microwave intensity at 12 GHz was measured for each sample, using Osaki's microwave method. The direction and the degree of collagen-fiber orientation for the cut specimens changed with changing position from the heel end to the anterior, along to the long axis of the calcaneus bone. The direction of orientation deviated by about -60 degrees from the direction of the long axis of the human lower limb, in the region between the heel end and the middle, and by about 60 degrees near the anterior. The position at which the orientation angle changed drastically from negative to positive corresponded to the neck defined as the position where a posterior face of the talus contacts the calcaneus. The results suggest that the mechanical stress applied to the neck of the calcaneus bone from the lower limb may effectively disperse, on average, in two different directions where the collagen fibers are oriented at the neck.

Effects of acute and chronic alacepril treatment on exercise capacity and hemodynamics in patients with heart failure: a preliminary study

OBJECTIVE

This study determined whether alacepril treatment improves exercise hemodynamics in patients with heart failure.

METHODS

Supine bicycle ergometer exercise was performed after administration of placebo and after acute and chronic (12 weeks) alacepril treatment in 4 patients with heart failure. Oxygen uptake (VO2), arterial oxygen saturation (SaO2), and mixed venous oxygen saturation (SvO2) were measured continuously using a pulse oxymeter and a fiber optic catheter. Cardiac index was calculated with Fick's equation.

RESULTS

Acute alacepril treatment did not significantly alter the VO2 or hemodynamics. After chronic alacepril treatment, peak VO2 increased (placebo vs chronic alacepril treatment: 17.7 +/- 2.8 vs 21.7 +/- 2.8 ml/min/kg, p < 0.05). Arteriovenous oxygen difference (SaO2 - SvO2) at peak exercise was not altered, however, cardiac index at peak exercise (5.07 0.67 vs 6.35 +/- 0.48 I/min/m2, p = 0.02) increased and stroke volume index at peak exercise (37.3 +/- 3.4 vs 46.5 +/- 1.1 ml/m2, p = 0.07) tended to increase.

CONCLUSIONS

Chronic treatment with alacepril improved maximal exercise capacity in patients with heart failure. The increased peak VO2 was primarily due to the increased cardiac index, but not due to the widening of arteriovenous oxygen difference. Therapy-induced increase in stroke volume index may contribute to the increased cardiac index at peak exercise in our patients with heart failure.

Biologically induced Po emission from fresh water

Behavior of Po in fresh waters was examined in laboratory culture experiments using fresh water collected from a small pool, Xi river and Xiqing lake, showing formation of volatile Po compounds followed by emission to air. Addition of tryptone to the fresh water cultures increased the emission of Po considerably along with a growth of microorganisms, suggesting a connection of chemoheterotrophs to Po emission. Participation of photoautotrophs was also considered because Po emission was increased when NaHCO3 was added to the fresh water cultures. The emission behavior of Po and S in these experiments appeared in different ways. The quantity of Po emitted was comparable to the previous culture experiments (Momoshima, Song, Osaki & Maeda, Environ. Sci. Technol., 35, 2956-2960, 2001) in which artificial culture medium containing 3% NaCl was used and inoculated with sea sediment extract. The biological support for Po emission, thus, would be a general phenomenon in fresh water as well as a seawater environment and is possibly a source for atmospheric Po.

Use of hair pores to determine the orientation of collagen fibers in skin

Most people are interested in recovery of skin defects caused by burn, scald or trauma from the aesthetic and functional point of view. It will occupy an important role for successful skin graft for patients with such skin defects that the orientation of collagen fibers in the grafted skin matches to the fiber orientation in surrounding skin. There have been, to my best knowledge, no methods for determining the orientation of collagen fibers in the skin from the clinical point of view. Recently, the author has found a new method for directly determining the collagen-fiber orientation without cutting samples from a calf leather by analyzing the anisotropic shape of hair pore. Its principle is based on the quantitative evaluation of collagen-fiber orientation by approximating a hair pore to an ellipse. The results obtained by the new method using hair pores were supported by the microwave method, mechanical measurements and scanning electron microscopy. Such a method will be applicable for determining the orientational distribution of collagen fibers in skins of animals and humans and give a valuable probe for performing skin grafting based on the scientific data of hair pores.

Formation and emission of volatile polonium compound by microbial activity and polonium methylation with methylcobalamin

We observed biologically mediated emission of Po from culture solution inoculated sea sediment extract and incubated under natural light/dark cycle condition or dark condition the emitted Po compound would be lipophilic because of effective collection in organic solvent. Sterilization of the culture medium with antibiotics or CuSO4 completely suppressed growth of microorganisms and resulted in no emission of Po, indicating biological activity of microorganisms is responsible for formation and emission of volatile Po compound. Po emission also occurred when seawater was used as a culture medium. Our finding indicates a possibility of biotic source for atmospheric Po in the environment, which has been believed to be originated from abiotic sources. We compared emission behavior of Po and S in the culture experiments, the elements belong to XVI group in the Periodical Table, and consider that their emission mechanisms involved would be different though the emission of both elements is supported by biological activity of microorganisms. One of the chemical forms of S emitted was confirmed to be dimethyl sulfide (DMS) but that of Po is not known. Methylation experiments of Po with methylcobalamin demonstrated a formation and emission of volatile Po compound. The methylation of Po with methylcobalamin might be related to the observed Po emission in the culture experiments.

Altered purine nucleotide degradation during exercise in patients with essential hypertension

Purine degradation occurs during strenuous muscle exercise and plasma levels of hypoxanthine (HX), purine degradation intermediate, increase. Purine nucleotide degradation has not been investigated in patients with essential hypertension (HTN). The present study determined whether purine nucleotide degradation is altered in patients with HTN. Cardiopulmonary exercise test was performed with serial measurements in blood lactate and plasma HX in 24 patients (14 men and 10 women) with essential HTN (World Health Organization [WHO] class I to II; mean age, 57.7 +/- 2.1 years) and 24 age-, sex-matched normal subjects. Exercise was terminated either by severe fatigue or excess blood pressure increase. Peak work rate (WR) (normal v HTN, 151 +/- 10 v 135 +/- 8 W, not significant [NS]) was not different, but peak oxygen uptake (peak Vo(2), 26.3 +/- 1.5 v 22.2 +/- 0.9 mL/min/kg, P <.05) and anaerobic threshold were lower in patients with HTN. Resting levels of blood lactate and plasma HX were similar, but the increment from rest to peak exercise (Delta) for lactate (Delta lactate: 4.4 +/- 0.4 v 3.4 +/- 0.4 mmol/L, P <.05) and for HX (Delta HX, 15.9 +/- 2.2 v 9.1 +/- 1.1 micromol/L, P <.05) were significantly smaller in patients with HTN. When normalized by the peak WR, Delta HX/peak WR (0.105 +/- 0.013 v 0.069 +/- 0.007 micromol/L/W, P <.05) was significantly lower in patients with HTN. Patients with HTN exhibited reduced HX response to exercise with impaired exercise capacity. The exercise-induced changes in plasma HX were smaller in patients with HT when normalized with peak WR. These results suggest that the purine nucleotide degradation is reduced in patients with HTN.

Comparison of cedar pollen-induced allergic rhinitis in passively and actively sensitized guinea pigs

We have developed an allergic rhinitis model in guinea pigs using Japanese cedar pollen as antigen. In the present study, we examined whether provocation by pollen induces similar magnitudes of rhinitis symptoms in passively and actively sensitized guinea pigs. One group of animals was actively sensitized by intranasal application of pollen extract, and another was passively sensitized by intraperitoneal injection with anti-pollen serum. Actively and passively sensitized groups were then challenged by repeated and a single pollen inhalation, respectively. In both groups, sneeze was induced immediately after the challenge. The actively sensitized animals developed not only early but also late nasal blockage, whereas the passively sensitized animals showed only early nasal blockage. In both groups, an H1 antagonist, mepyramine, inhibited the occurrence of sneezing but did not inhibit nasal blockage. Nasal hyperresponsiveness to intranasal instillation of leukotriene D4 was obvious only in the actively sensitized animals. We thus conclude that although early nasal blockage is induced by a single antigen-antibody reaction, repetitive anaphylactic reaction is required for occurrence of late nasal blockage and hyperresponsiveness to stimuli. Furthermore, histamine plays a central role in induction of sneezing but not in nasal blockage, irrespective of whether animals are actively or passively sensitized.

L-arabinose feeding prevents increases due to dietary sucrose in lipogenic enzymes and triacylglycerol levels in rats

L-Arabinose is a natural, poorly absorbed pentose that selectively inhibits intestinal sucrase activity. To investigate the effects of L-arabinose feeding on lipogenesis due to its inhibition of sucrase, rats were fed 0-30 g sucrose/100 g diets containing 0-1 g L-arabinose/100 g for 10 d. Lipogenic enzyme activities and triacylglycerol concentrations in the liver were significantly increased by dietary sucrose, and arabinose significantly prevented these increases. Arabinose feeding reduced the weights of epididymal adipose tissue. Moreover, plasma insulin and triacylglycerol concentrations were significantly reduced by dietary L-arabinose. These findings suggest that L-arabinose inhibits intestinal sucrase activity, thereby reducing sucrose utilization, and consequently decreasing lipogenesis.