Implementation of a new neurochip using stochastic logic

Even though many neurochips have been developed and investigated, the best suitable way for implementation has not been known clearly. Our approach is to exploit stochastic logic for various operations required for neural functions. The advantage of stochastic logic is that complex operations can be implemented with a few ordinary logic gates. On the other hand, the operation speed is not so fast since stochastic logic requires certain accumulation time for averaging. However, a huge integration can be achieved and its reliability is high because all of operations are done on digital circuits. Furthermore, we propose a nonmonotonic neuron realized by stochastic logic, since the nonmonotonic property is efficient for the performance enhancement in association and learning. In this paper, we show the circuit design and measurement results of a neurochip comprising 50 neurons are shown. The advantages of nonmonotonic and stochastic properties are shown clearly.

Laser ion acceleration via control of the near-critical density target

Duration-controlled amplified spontaneous emission with an intensity of 10(13) W/cm(2) is used to convert a 7.5-microm -thick polyimide foil into a near-critical plasma, in which the p -polarized, 45-fs , 10(19) -Wcm (2) laser pulse generates 3.8-MeV protons, emitted at some angle between the target normal and the laser propagation direction of 45 degrees . Particle-in-cell simulations reveal that the efficient proton acceleration is due to the generation of a quasistatic magnetic field on the target rear side with magnetic pressure inducing and sustaining a charge separation electrostatic field.

Retrospective cohort study between selective and standard C3-7 laminoplasty. Minimum 2-year follow-up study

A total of 64 patients with cervical spondylotic myelopathy (CSM) were assessed in this study. Forty-two patients underwent selective expansive open-door laminoplasty (ELAP). Twenty-two patients who underwent conventional C3-7 ELAP served as controls. There were no significant differences in recovery rate of JOA scores, C2-C7 angle or cervical range of motion between two groups. Incidence of axial symptoms and segmental motor paralysis in selective ELAP was significantly lower than those in the C3-7 ELAP. Size of anterior compression mass, postoperative spinal cord positions and decompression conditions were evaluated using preoperative or postoperative MRI in 50 of 64 patients. There was a positive correlation between number of expanded laminae and maximum anterior spaces of spinal cord. Incomplete decompression was developed in three of 37 patients in selective ELAP and in two of 13 patients in C3-7ELAP. Mean size of anterior compression mass at incomplete decompression levels was significantly greater than that at complete decompression levels. Since, there was less posterior movement of the spinal cord in selective ELAP than that in C3-7ELAP, minute concerns about size of anterior compression mass is necessary to decide the number of expanded laminae. Overall, selective ELAP was less invasive and useful in reducing axial symptoms and segmental motor paralysis. This new surgical strategy was effective in improving the surgical outcomes of CSM, and short-term results were satisfactory.

Pituitary adenylate cyclase-activating polypeptide is associated with schizophrenia

Pituitary adenylate cyclase-activating polypeptide (PACAP, ADCYAP1: adenylate cyclase-activating polypeptide 1), a neuropeptide with neurotransmission modulating activity, is a promising schizophrenia candidate gene. Here, we provide evidence that genetic variants of the genes encoding PACAP and its receptor, PAC1, are associated with schizophrenia. We studied the effects of the associated polymorphism in the PACAP gene on neurobiological traits related to risk for schizophrenia. This allele of the PACAP gene, which is overrepresented in schizophrenia patients, was associated with reduced hippocampal volume and poorer memory performance. Abnormal behaviors in PACAP knockout mice, including elevated locomotor activity and deficits in prepulse inhibition of the startle response, were reversed by treatment with an atypical antipsychotic, risperidone. These convergent data suggest that alterations in PACAP signaling might contribute to the pathogenesis of schizophrenia.

Extended storage of granulocyte concentrates mobilized by G-CSF with/without dexamethasone and collected by bag separation method

The aim of this study was to examine the extended storage of granulocyte concentrates mobilized by granulocyte-colony-stimulating factor (G-CSF) with/without dexamethasone (DEX) and collected by a bag separation method. Ten healthy adult volunteers donated blood three times: twice after granulocyte mobilization by (1) injecting G-CSF at 3 microg kg(-1) subcutaneously (s.c.) and (2) injecting G-CSF at 3 microg kg(-1) s.c. + DEX at 8 mg per oral and once (3) for a baseline control without any forms of mobilization. Granulocytes were collected by a bag separation method. The functions (phagocytosis and oxidative killing levels), viability and levels of interleukin (IL)-1beta, IL-8, IL-6 and tumour necrosis factor-alpha of granulocytes were measured. The average numbers of granulocytes collected from 200-mL samples of whole blood from the G-CSF and G-CSF + DEX groups were 35.1 x 10(8) and 49.4 x 10(8), respectively. Phagocytosis level, oxidative killing level and the viability of the granulocytes mobilized by G-CSF with/without DEX were well maintained for up to 72 h of storage after collection. The levels of the cytokines increased in a time-dependent manner. The in vitro phagocytosis level, oxidative killing level and the viability of granulocytes mobilized by G-CSF with/without DEX and collected by bag separation method can be maintained for as long as 72 h after collection.

Detection of small particles in fluid flow using a self-mixing laser

We describe a highly sensitive, real-time method of detecting small particles in a fluid flow by self-mixing laser Doppler measurement with a laser-diode-pumped, thin-slice solid-state laser with extremely high optical sensitivity. Asymmetric power spectra of the laser output modulated by the re-injected scattered light from the small particles moving in a dilute sample-flow, through a small-diameter glass pipe, were observed. The observed power spectra are shown to reflect the velocity distribution of the fluid flow, which obeys Poiseuille's law. Quick measurements of flow rate and kinetic viscosities of water-glycerol mixtures were also performed successfully. Measurable low-concentration limits for 262-nm polystyrene latex spheres and 3-mum red blood cells in a fluid flow were below 1 and 10 ppm, respectively, in the present self-mixing laser Doppler velocimeter system.

Abductor pollicis longus transfer to restore index abduction in severe cases of cubital tunnel syndrome

Transfer of the abductor pollicis longus tendon to restore index abduction was performed simultaneously with ulnar nerve decompression in severe cases of cubital tunnel syndrome. Eighteen elbows in 18 patients were evaluated with an average follow-up period of 46 (range 12-120) months. The status of the ulnar nerve palsy was evaluated by the Yasutake's scoring method. The mean score improved from 48 points pre-operatively to 78 points at final follow-up (maximum score 100 points). Pinch strength improved from 39% of the opposite side pre-operatively to 81% finally and it reached a plateau one year postoperatively. Despite this improvement in pinch strength, atrophy of the interosseous muscle did not disappear in nine of 12 patients with a follow-up of more than two years. All patients were satisfied with the results of increased strength and stability in pinching ability. No complications occurred.

Spontaneous resorption in recurrent intradural lumbar disc herniation

✓The authors report a case of spontaneous resorption of intradural disc material in a patient with recurrent intradural lumbar disc herniation and review magnetic resonance (MR) imaging and histopathological findings. Intradural lumbar disc herniation is rare, and most patients with this condition require surgical intervention due to severe leg pain and vesicorectal disturbance. In the present case, however, the recurrent intradural herniated mass had completely disappeared by 9 months after onset. Histological examination of intradural herniated disc tissue demonstrated infiltrated macrophages and angiogenesis within the herniated tissue, and Gd-enhanced MR images showed rim enhancement not only at the initial presentation, but also at recurrence.

The authors conclude that when rim enhancement is present on Gd-enhanced MR images, there is a possibility of spontaneous resorption even though the herniated mass may be located within the intradural space. Moreover, when radiculopathy is controllable and cauda equina syndrome is absent, conservative therapy can be selected.

Automated discrimination between very early Alzheimer disease and controls using an easy Z-score imaging system for multicenter brain perfusion single-photon emission tomography

BACKGROUND AND PURPOSE

In Alzheimer disease (AD), a peculiar regional cerebral blood flow (rCBF) abnormality has been reported in the posterior cingulate gyri and precunei, even at a very early stage. We performed a multicenter brain perfusion single-photon emission tomography (SPECT) study to evaluate the discrimination ability of an easy Z-score imaging system (eZIS) with a common normal data base between patients with very early AD at the stage of mild cognitive impairment and age-matched healthy controls.

MATERIALS AND METHODS

For a multicenter study, SPECT images of 40 patients with AD and 40 healthy volunteers were acquired from 4 gamma camera systems in 4 different institutions. Systematic differences of SPECT images between gamma cameras were corrected by using conversion maps calculated from the SPECT images of the same brain phantom. Receiver operating characteristic (ROC) analysis was performed to discriminate patients and controls by using a Z-score in the volume of interest (VOI), which had been defined as a region related to AD in subjects other than those in a multicenter study.

RESULTS

Bilateral posterior cingulate gyri, precunei, and parietal cortices were defined as a VOI showing rCBF reduction in very early AD. A new indicator of rCBF abnormality in the VOI provided 86% accuracy for distinction of AD and healthy controls in the multicenter study. The area under the ROC curve was 0.934.

CONCLUSION

Because an eZIS can use a common normal data base by converting site-specific SPECT data to the core data, the eZIS was useful for automated diagnosis of very early AD in routine studies in multiple institutions.

Hemimegalencephaly: a study of abnormalities occurring outside the involved hemisphere

BACKGROUND AND PURPOSE

Hemimegalencephaly is a rare but well-known congenital malformation with ipsilateral enlargement of the hemicerebrum. However, very little is known about changes in structures outside the involved hemisphere in patients with this condition. We investigated morphologic abnormalities occurring outside the affected hemisphere by MR imaging in a large series of patients with hemimegalencephaly.

MATERIALS AND METHODS

MR imaging findings for 30 patients with hemimegalencephaly were retrospectively reviewed and evaluated for structures outside the involved hemisphere on routine MR images, such as cranial nerves (I, II, V), brain vessels, subdural and subarachnoid spaces, brain stem, and cerebellum, on both the ipsilateral and contralateral sides.

RESULTS

The ipsilateral olfactory and optic nerves were enlarged in 8 (26.7%) and 1 (3.3%) of the 30 patients, respectively, without enlargement on the contralateral side. No asymmetry was noted in the trigeminal nerves. Asymmetric vascular dilations in the ipsilateral cerebral hemisphere were observed in 12 of the 30 patients (40%), in deep cerebral vessels in 11 patients (36.7%), and in superficial cerebral vessels in 8 patients (26.7%). Ipsilateral brain stem and hemicerebellar asymmetric enlargement was detected in 2 patients (6.7%) and 14 patients (46.7%), respectively. Abnormal cerebellar folia were observed on the ipsilateral side in 6 patients (20%) and on the contralateral side in 3 patients (10%).

CONCLUSION

Ipsilateral olfactory nerve enlargement, cerebral vascular dilations, cerebellar enlargement, and bilateral or ipsilateral abnormal architecture of the cerebellar folia are often associated with hemimegalencephaly.

In vivo effects of cyclic administration of 15-deoxyspergualin on leucocyte function in patients with Wegener's granulomatosis

15-Deoxyspergualin (DSG) is an alternative treatment modality for Wegener's granulomatosis (WG) patients refractory to conventional treatment. Nevertheless, it is unclear how DSG modulates disease activity in these patients. This study was conducted to investigate which parameters of adaptive and acquired immunity were influenced during two subsequent cycles of DSG treatment. Emphasis was put upon T cell and monocyte activation, neutrophil function and surface expression of proteinase-3 (PR-3). Anti-CD3/anti-CD28 and interleukin (IL)-15/IL-7-mediated T cell proliferation were assessed by fluorescence activated cell sorter (FACS) analysis using carboxyfluorescein succinimidyl ester (CSFE) labelling. Interferon (IFN)-gamma and IL-10 production were determined in the supernatants of these cultures by enzyme-linked immunosorbent assay. Monocyte activation was assessed in lipopolysaccharide (LPS)-stimulated whole blood, using tumour necrosis factor (TNF)-alpha as read-out. Neutrophil function was determined by measuring oxidative burst, chemotaxis and phagocytosis. T cell activation markers and PR3 expression were measured by FACS. All parameters were determined directly before and after each DSG cycle. Anti-CD3/anti-CD28-mediated T cell proliferation was reduced directly after DSG treatment. Directly before a subsequent cycle of DSG was started, T cell proliferation was increased. Similar findings were observed for IFN-gamma and IL-10 production by T cells. DSG did not influence IL-15/IL-7-mediated T cell proliferation. LPS-mediated TNF-alpha production was also impaired directly after DSG treatment. No influence on T cell activation markers, neutrophil function and surface PR-3 expression was observed in peripheral blood of these patients. Our data demonstrate that DSG influences T cell and monocyte activation in a reversible fashion. Although DSG causes neutropenia in these patients, it does not influence neutrophil function.

A new operative procedure using a Küntcher nail for a periprosthetic supracondylar femoral fracture after revision total knee arthroplasty: a case report

Periprosthetic supracondylar femoral fractures after total knee arthroplasty (TKA) are difficult surgical problems. We report a case of an 84-year-old female, in which an original method was applied to treat a periprosthetic supracondylar femoral nonunion just proximal a femoral component. The new method features extending the stem of the femoral component with a Küntcher nail. Eventually bony union was obtained and the patient is now able to walk without any support.

Tissue engineering of articular cartilage with autologous cultured adipose tissue-derived stromal cells using atelocollagen honeycomb-shaped scaffold with a membrane sealing in rabbits

Adipose tissue derived stromal cells (ATSCs), which were isolated from adipose tissue of rabbit, have shown to possess multipotential, that is, they differentiate into osteoblasts and adipocytes in plate-culturing and into chondrocytes in an established aggregate culture using defined differentiation-inductive medium. The aim of this study was to evaluate the utility of ATSCs in tissue engineering procedures for repair of articular cartilage-defects using the atelocollagen honeycomb-shaped scaffold with a membrane sealing (ACHMS-scaffold). We intended to repair full-thickness articular cartilage defects in rabbit knees using autologously cultured ATSCs embedded in the ACHMS-scaffold. ATSCs were incubated within the ACHMS-scaffold to allow a high density and three-dimensional culture with control medium. An articular cartilage defect was created on the patellar groove of the femur, and the defect was filled with the ATSCs-containing ACHMS-scaffold, ACHMS-scaffold alone, or empty (control). Twelve weeks after the operation, the histological analyses showed that only the defects treated with the ATSCs-containing ACHMS-scaffold were filled with reparative hyaline cartilage, highly expressed Type II collagen. These results indicate that transplantation of autologous ATSCs-containing ACHMS-scaffold is effective in repairing articular cartilage defects.

Severe scoliosis associated with Costello syndrome: a case report

Costello syndrome is characterised by dwarfism, unique cutaneous lesions, a distinct facial gestalt, and mental retardation. There have been no detailed reports of severe spinal deformities requiring surgical treatment as a complication of Costello syndrome. We report a case of a 10-year-old girl with progressive scoliosis associated with Costello syndrome. She underwent anterior release and posterior surgical correction and fusion from T5 to L2 using a third generation hook and rod system plus spinous process wiring. Congenital portal vein deficiency and coagulopathy were other major complications. At 15-month follow-up, the patient had good balance and no evidence of instrumentation failure.

Postoperative change of the cross-sectional area of back musculature after 5 surgical procedures as assessed by magnetic resonance imaging

Many investigators have reported that persistent low back pain may occur after posterior surgical intervention, and studies have investigated the histologic and histochemical changes in back muscle after posterior lumbar spine surgery. The purpose of the current study is to compare the pre- and postoperative cross-sectional area of the back musculature among 5 surgical groups including anterior lumbar interbody fusion, which has no direct invasion of the back musculature, using magnetic resonance imaging, and to correlate the clinical results with the degree of atrophy. The cross-sectional area of the back musculature was measured before and after surgery in T2-weighted axial magnetic resonance images using a computer-linked digitizer. The degree of atrophy (atrophy ratio) was calculated as a ratio of the postoperative cross-sectional area to the preoperative cross-sectional area. Clinical results were evaluated using the Japanese Orthopaedic Association's scores for the management of low back pain. Atrophy of the back musculature was confirmed in each group. However, no significant difference was seen in the atrophy ratio between the groups. Back musculature atrophy occurred even in anterior lumbar interbody fusion, which does not involve any direct surgery of the back muscle. A positive correlation was noted between the atrophy ratio and operation time only in posterior surgery, especially in nonfusion surgery. In conclusion, the current study suggests that a shorter operation time may minimize back muscle injury, and shows that factors inducing back musculature atrophy include not only direct invasion of the back muscle via a posterior approach, but also postoperative external fixation.

Nonmyeloablative stem cell transplantation for nonmalignant diseases in children with severe organ dysfunction

Allogeneic stem cell transplantation (SCT) can cure several nonmalignant diseases in children. However, patients frequently have significant morbidity before transplantation and there is a high transplant-related mortality. Nonmyeloablative SCT might achieve the same goals but with less toxicity. Six pediatric patients with nonmalignant diseases underwent nonmyeloablative SCT from different stem cell sources. All patients were conditioned with fludarabine/melphalan with additional anti-thymocyte globulin for haploidentical grafts and prophylaxis for graft-versus-host disease (GVHD) consisting of tacrolimus and methotrexate with additional prednisolone for haploidentical grafts. Hematopoietic stem cells were neither T-cell depleted nor purged. All patients had severe organ dysfunction that precluded transplantation with conventional conditioning. Five of the six are alive and in complete disease resolution at a median of 19 months (range, 7-53 months) after SCT. One patient died of bacteremia before engraftment. Three patients achieved complete donor chimerism. Two patients remained stable mixed chimerism. Short-term toxicities were minimal. Acute and chronic GVHD were not seen. In summary, the fludarabine-based nonmyeloablative regimen followed by SCT provides a good approach for children with nonmalignant diseases. Even patients with severe organ dysfunctions had adequate engraftment with acceptable toxicities.

Therapeutic transfusions of granulocytes collected by simple bag method for children with cancer and neutropenic infections: results of a single-centre pilot study

BACKGROUND AND OBJECTIVES

Granulocyte transfusion therapy (GTX) can be effective for life-threatening infections unresponsive to conventional antimicrobial therapies in severely neutropenic children with cancer. We developed a new granulocyte collection method, named the 'bag method', in which apheresis, hydroxyethyl starch (HES) or dexamethasone are not used. We undertook a pilot study to determine the feasibility and the safety of GTX collected by the bag method for children with cancer and life-threatening infections.

MATERIALS AND METHODS

A total of 25 GTX were administered to 13 patients (median age 3 years, range: 0.3-17; median weight 10.6 kg, range: 4.5-49.8) with neutropenia-related infections. Thirteen blood-relative donors received granulocyte colony-stimulating factor (G-CSF) (5-10 microg/kg), subcutaneously, 14 h before collection. Major end-points were granulocyte yields, post-transfusion absolute neutrophil counts (ANC) in patients, donor and patient safety, and clinical outcome on day 30.

RESULTS

The median yield of ANC per 400 ml of processed whole blood was 6.2 x 10(9) (range: 2.5-15.0 x 10(9)). Patients received a mean of 6.4 +/- 0.8 x 10(8) granulocytes per kg of body weight per transfusion. The 1-h and 24-h post-transfusion ANC rose to 607 +/- 124/microl and 704 +/- 300/microl, respectively, from the baseline of 21/microl before the first GTX. Adverse reactions were observed in five of 13 donors (bone pain, headache, vasovagal reaction; all < or = grade 2) and in two of 25 transfusions of 13 patients (transient hypoxia; grade 3). Ten patients had favourable responses, and infection resolved in nine patients.

CONCLUSIONS

The bag method without apheresis relieves the physical load of donors and enables patients with a low body weight to provide an adequate dose of granulocytes.

Upregulated expression of inducible nitric oxide synthase plays a key role in early apoptosis after anterior cruciate ligament injury

The reason that the anterior cruciate ligament (ACL) has a very poor healing potential after injury is not well understood. In this study, we investigated the role of nitric oxide (NO) in the apoptotic cell death of ACL cells using a rabbit model and in vitro cell culture. The apoptosis of ACL cells in vivo was analyzed by TUNEL assay and electron microscopy. NO synthase (NOS) expression was observed by immunohistochemical analysis. ACL cells were cultured and the susceptibility to NO-induced apoptosis was tested. Inducible NOS (iNOS) expression after treatment with cytokines was examined by immunohistochemical and RT-PCR analyses. Mitogen-activated protein kinase (MAPK) inhibitors were used for the analysis of downstream signals. A significant number of apoptotic cells were observed on days 1 to 3 after injury; the apoptotic rate returned to the control level by day 7. Upregulation of iNOS in the ACL remnant was observed at day 1. Intraarticular injection of NOS inhibitor suppressed the apoptotic rate. Isolated ACL cells showed much higher susceptibility to NO-induced apoptosis than did medial collateral ligament cells. IL-1beta stimulated ACL cells to upregulate iNOS mRNA and increase NO production. p38 MAPK inhibitor decreased NO-induced apoptosis. Rapid iNOS induction after injury contributes to the high apoptotic rate of ACL cells, and this may partly account for the poor healing capacity of this ligament. iNOS and NO production is suggested to be stimulated by IL-1beta, and NO activates the p38 MAPK pathway and triggers an apoptotic signal in ACL cells.