Selective loss of parvalbumin-positive GABAergic interneurons in the cerebral cortex of maternally stressed Gad1-heterozygous mouse offspring

Exposure to maternal stress (MS) and mutations in GAD1, which encodes the γ-aminobutyric acid (GABA) synthesizing enzyme glutamate decarboxylase (GAD) 67, are both risk factors for psychiatric disorders. However, the relationship between these risk factors remains unclear. Interestingly, the critical period of MS for psychiatric disorders in offspring corresponds to the period of GABAergic neuron neurogenesis and migration in the fetal brain, that is, in the late stage of gestation. Indeed, decrement of parvalbumin (PV)-positive GABAergic interneurons in the medial prefrontal cortex (mPFC) and hippocampus (HIP) has often been observed in schizophrenia patients. In the present study, we used GAD67-green fluorescent protein (GFP) knock-in mice (that is, mice in which the Gad1 gene is heterozygously deleted; GAD67(+/GFP)) that underwent prenatal stress from embryonic day 15.0 to 17.5 and monitored PV-positive GABAergic neurons to address the interaction between Gad1 disruption and stress. Administration of 5-bromo-2-deoxyuridine revealed that neurogenesis of GFP-positive GABAergic neurons, but not cortical plate cells, was significantly diminished in fetal brains during MS. Differential expression of glucocorticoid receptors by different progenitor cell types may underlie this differential outcome. Postnatally, the density of PV-positive, but not PV-negative, GABAergic neurons was significantly decreased in the mPFC, HIP and somatosensory cortex but not in the motor cortex of GAD67(+/GFP) mice. By contrast, these findings were not observed in wild-type (GAD67(+/+)) offspring. These results suggest that prenatal stress, in addition to heterozygous deletion of Gad1, could specifically disturb the proliferation of neurons destined to be PV-positive GABAergic interneurons.

Experiments with biased side electrodes in electron cyclotron resonance ion sources

The output of highly charged ions from an electron cyclotron resonance ion source (ECRIS) consists of ionic losses from a highly confined plasma. Therefore, an increase of the output of the ions of interest always is a compromise between an increase in the confinement and an increase of the losses. One route towards a solution consists of attacking the losses in directions - i.e., radial directions - that do not contribute to the required output. This was demonstrated in an experiment (using the Kei ECRIS at NIRS, Japan) where radial losses were electrostatically reduced by positively biasing one set of six "side" electrodes surrounding the plasma in side-ward directions attached (insulated) to the cylindrical wall of the plasma chamber. Recently new studies were performed in two laboratories using two essentially different ion sources. At the BioNano ECRIS (Toyo University, Japan) various sets of electrodes were used; each of the electrodes could be biased individually. At the Atomki ECRIS (Hungary), one movable, off-axis side electrode was applied in technically two versions. The measurements show indeed a decrease of ionic losses but different effectivities as compared to the biased disk.

Synthesis of endohedral iron-fullerenes by ion implantation

In this paper, we discuss the results of our study of the synthesis of endohedral iron-fullerenes. A low energy Fe(+) ion beam was irradiated to C60 thin film by using a deceleration system. Fe(+)-irradiated C60 thin film was analyzed by high performance liquid chromatography and laser desorption/ ionization time-of-flight mass spectrometry. We investigated the performance of the deceleration system for using a Fe(+) beam with low energy. In addition, we attempted to isolate the synthesized material from a Fe(+)-irradiated C60 thin film by high performance liquid chromatography.

A study on prevention of an electric discharge at an extraction electrode of an electron cyclotron resonance ion source for cancer therapy

A compact ECR ion source has utilized for carbon radiotherapy. In order to increase beam intensity with higher electric field at the extraction electrode and be better ion supply stability for long periods, electric geometry and surface conditions of an extraction electrode have been studied. Focusing attention on black deposited substances on the extraction electrode, which were observed around the extraction electrode after long-term use, the relation between black deposited substances and the electrical insulation property is investigated. The black deposited substances were inspected for the thickness of deposit, surface roughness, structural arrangement examined using Raman spectroscopy, and characteristics of electric discharge in a test bench, which was set up to simulate the ECR ion source.

Status of the Bio-Nano electron cyclotron resonance ion source at Toyo University

In the paper, the material science experiments, carried out recently using the Bio-Nano electron cyclotron resonance ion source (ECRIS) at Toyo University, are reported. We have investigated several methods to synthesize endohedral C60 using ion-ion and ion-molecule collision reaction in the ECRIS. Because of the simplicity of the configuration, we can install a large choice of additional equipment in the ECRIS. The Bio-Nano ECRIS is suitable not only to test the materials production but also to test technical developments to improve or understand the performance of an ECRIS.

Fullerene-rare gas mixed plasmas in an electron cyclotron resonance ion source

A synthesis technology of endohedral fullerenes such as Fe@C60 has developed with an electron cyclotron resonance (ECR) ion source. The production of N@C60 was reported. However, the yield was quite low, since most fullerene molecules were broken in the ECR plasma. We have adopted gas-mixing techniques in order to cool the plasma and then reduce fullerene dissociation. Mass spectra of ion beams extracted from fullerene-He, Ar or Xe mixed plasmas were observed with a Faraday cup. From the results, the He gas mixing technique is effective against fullerene destruction.

Continuing increased risk of oral/esophageal cancer after allogeneic hematopoietic stem cell transplantation in adults in association with chronic graft-versus-host disease

BACKGROUND

The number of long-term survivors after hematopoietic stem cell transplantation (HSCT) showed steady increase in the past two decades. Second malignancies after HSCT are a devastating late complication. We analyzed the incidence of, risk compared with that in the general population, and risk factors for secondary solid cancers.

PATIENTS AND METHODS

Patients were 17 545 adult recipients of a first allogeneic stem cell transplantation between 1990 and 2007 in Japan. Risks of developing secondary solid tumors were compared with general population by using standard incidence ratios (SIRs).

RESULTS

Two-hundred sixty-nine secondary solid cancers were identified. The cumulative incidence was 0.7% [95% confidence interval (CI), 0.6%-0.9%] at 5 years and 1.7% (95% CI, 1.4%-1.9%) at 10 years after transplant. The risk was significantly higher than that in the general population (SIR=1.8, 95% CI, 1.5-2.0). Risk was higher for oral cancer (SIR=15.7, 95% CI, 12.1-20.1), esophageal cancer (SIR=8.5, 95% CI, 6.1-11.5), colon cancer (SIR=1.9, 95% CI, 1.2-2.7), skin cancer (SIR=7.2, 95% CI, 3.9-12.4), and brain/nervous system cancer (SIR=4.1, 95% CI, 1.6-8.4). The risk of developing oral, esophageal, or skin cancer was higher at all times after 1-year post-transplant. Extensive-type chronic graft-versus-host disease (GVHD) was a significant risk factor for the development of all solid tumors (RR=1.8, P<0.001), as well as for oral (RR=2.9, P<0.001) and esophageal (RR=5.3, P<0.001) cancers. Limited-type chronic GVHD was an independent risk factor for skin cancers (RR=5.8, P=0.016).

CONCLUSION

Recipients of allogeneic HSCT had a significantly higher ∼2-fold risk of developing secondary solid cancers than the general population. Lifelong screening for high-risk organ sites, especially oral or esophageal cancers, is important for recipients with active, or a history of, chronic GVHD.

Genetic deletion of granzyme B does not confer resistance to the development of spontaneous diabetes in non-obese diabetic mice

Granzyme B (GzmB) and perforin are proteins, secreted mainly by natural killer cells and cytotoxic T lymphocytes that are largely responsible for the induction of apoptosis in target cells. Because type 1 diabetes results from the selective destruction of β cells and perforin deficiency effectively reduces diabetes in non-obese diabetic (NOD) mice, it can be deduced that β cell apoptosis involves the GzmB/perforin pathway. However, the relevance of GzmB remains totally unknown in non-obese diabetic (NOD) mice. In this study we have focused on GzmB and examined the consequence of GzmB deficiency in NOD mice. We found that NOD.GzmB(-/-) mice developed diabetes spontaneously with kinetics similar to those of wild-type NOD (wt-NOD) mice. Adoptive transfer study with regulatory T cell (Treg )-depleted splenocytes (SPCs) into NOD-SCID mice or in-vivo Treg depletion by anti-CD25 antibody at 4 weeks of age comparably induced the rapid progression of diabetes in the NOD.GzmB(-/-) mice and wt-NOD mice. Expression of GzmA and Fas was enhanced in the islets from pre-diabetic NOD.GzmB(-/-) mice. In contrast to spontaneous diabetes, GzmB deficiency suppressed the development of cyclophosphamide-promoted diabetes in male NOD mice. Cyclophosphamide treatment led to a significantly lower percentage of apoptotic CD4(+) , CD8(+) and CD4(+) CD25(+) T cells in SPCs from NOD.GzmB(-/-) mice than those from wt-NOD mice. In conclusion, GzmB, in contrast to perforin, is not essentially involved in the effector mechanisms for β cell destruction in NOD mice.

Double deficiency in IL-17 and IFN-γ signalling significantly suppresses the development of diabetes in the NOD mouse

AIMS/HYPOTHESIS

T helper type (Th) 17 cells have been shown to play important roles in mouse models of several autoimmune diseases that have been classified as Th1 diseases. In the NOD mouse, the relevance of Th1 and Th17 is controversial, because single-cytokine-deficient NOD mice develop diabetes similarly to wild-type NOD mice.

METHODS

We studied the impact of IL-17/IFN-γ receptor double deficiency in NOD mice on the development of insulitis/diabetes compared with IL-17 single-deficient mice and wild-type mice by monitoring diabetes-related phenotypes. The lymphocyte phenotypes were determined by flow cytometric analysis.

RESULTS

IL-17 single-deficient NOD mice showed delayed onset of diabetes and reduced severity of insulitis, but the cumulative incidence of longstanding diabetes in the IL-17-deficient mice was similar to that in wild-type mice. The IL-17/IFN-γ receptor double-deficient NOD mice showed an apparent decline in longstanding diabetes onset, but not in insulitis compared with that in the IL-17 single-deficient mice. We also found that double-deficient NOD mice had a severe lymphopenic phenotype and preferential increase in regulatory T cells among CD4(+) T cells compared with the IL-17 single-deficient mice and wild-type NOD mice. An adoptive transfer study with CD4(+)CD25(-) T cells from young non-diabetic IL-17 single-deficient NOD mice, but not those from older mice, showed significantly delayed disease onset in immune-deficient hosts compared with the corresponding wild-type mice.

CONCLUSIONS/INTERPRETATION

These results indicate that IL-17/Th17 participates in the development of insulitis and that both IL-17 and IFN-γ signalling may synergistically contribute to the development of diabetes in NOD mice.

Intracerebral hemorrhage in patients with chronic liver disease

The characteristics of intracerebral hemorrhage (ICH) accompanying chronic liver disease (CLD) were investigated in ICH patients hospitalized between 1998 and 2008 divided into the CLD group (55 ICHs in 49 patients) and the idiopathic group without CLD (668 ICHs in 648 patients). The CLD group included a subgroup with liver cirrhosis (LC). Age, sex, history of hypertension, Glasgow Coma Scale (GCS) score on admission, and hematoma locations were reviewed. Outcomes on discharge and causes of in-hospital death were also studied. Factors associated with life prognosis in CLD patients were investigated using uni- and multivariate analyses. History of hypertension and deep cerebral hemorrhage were less frequent in the LC subgroup compared to the idiopathic group. Distributions of GCS scores on admission were not significantly different, but incidence of in-hospital death was significantly higher in the CLD group than in the idiopathic group. LC was an independent prognostic factor for CLD patients, but hematoma enlargement was not. Death primarily due to ICH was less frequent in the CLD group than in the idiopathic group. In conclusion, hemostatic disorders seemed to be related to site of hemorrhage, but not to life prognosis in the CLD group. Prognosis was mainly worsened by non-neurological complications.

P2X7 receptor and cytokines contribute to extra-territorial facial pain

The whisker pad area (WP) is innervated by the second branch of the trigeminal nerve and experiences allodynia and hyperalgesia following transection of the mental nerve (MN; the third branch of the trigeminal nerve). However, the mechanisms of this extra-territorial pain remain unclear. The ionotropic P2X(7) ATP receptor (P2X(7)) in microglia is known to potentiate, via cytokines, the perception of noxious stimuli, raising the possibility that P2X(7) and cytokines are involved in this extra-territorial pain. One day after MN transection (MNT), WP allodynia/hyperalgesia developed, which lasted for > 8 wks. Activation of microglia and up-regulation of P2X(7), membrane-bound tumor necrosis factor (TNF)-α (mTNF-α), and soluble TNF-α (sTNF-α) in the trigeminal sensory nuclear complex (TNC) were evident for up to 6 wks after MNT. Allodynia/hyperalgesia after MNT was blocked by intracisternal administration of etanercept, a recombinant TNF-α receptor (p75)-Fc fusion protein. Intracisternal A438079, a P2X(7) antagonist, also attenuated allodynia/hyperalgesia and blocked up-regulation of mTNF-α and sTNF-α in the TNC. We conclude that sTNF-α released by microglia following P2X(7) activation may be important in both the initiation and maintenance of extra-territorial pain after MNT.

Effects of estrogen and tamoxifen on the MAP kinase cascade in experimental rat breast cancer

The mitogen-activated protein kinase (MAPK) cascade, which includes MAPK, MAP kinase kinase (MAPKK) and Raf-l, is involved in the signal transduction of growth factor receptors. We found that the MAPK and Raf-l proteins are increased in human breast cancer. Activated MAPKK was also observed. We then investigated whether the MAPK cascade is activated when 7,12-dimethylbenz(a) anthracene (DMBA)-induced rat mammary cancer is treated with 17 beta-estradiol (E-2). Ovariectomy suppressed MAPK expression in tumors, and E-2 administration induced the activation of MAPK in ovariectomized rats. We also investigated the effects of tamoxifen (TAM) on proliferation and the MAPK cascade in DMBA-induced rat mammary cancers. Although tumor size was reduced significantly by TAM, the expression of the MAPK and Raf-l proteins did not decrease. Additionally, MAPK and Raf-l protein expression increased in tumors of ovariectomized rats given TAM, despite a reduction in the size of the tumors. These results suggest that the activated MAPK cascade is important in human breast cancer, and is an important mechanism in the estrogen-dependent growth of DMBA-induced rat mammary cancer. TAM shows E-2-antagonistic effects on tumor proliferation, and E-2-agonistic effects on the MAPK cascade.

Low energy Fe+ beam irradiation to C60 thin film

We have developed an electron cyclotron resonance ion source apparatus, which is designed for the production of endohedral fullerene. In this study, we irradiated the Fe(+) beam to the C(60) thin film. We changed the experimental condition of the dose and the ion energy. We could observe the Fe + C(60) peak by analysis of the time-of-flight mass spectrometry. The highest intensity of the Fe + C(60) peak was observed at the ion energy of 200 eV. The Fe + C(60) peak intensity tended to become high in the case of long irradiation time and large dose.

Laser and focused ion beam combined machining for micro dies

We have developed a laser and focused ion beam (FIB) compound process for press mold dies of a micro lens array (MLA) and a micro needle array (MNA) in a glassy carbon (GC). The press mold die of the MLA was roughly fabricated by UV-YAG laser. After this process, we finished this surface by scanning FIB. As a result, higher accuracy and good roughness of surface profile can be realized. An optical glass is used to confirm the shape of lens. Moreover, we fabricated 6 × 6 through-holes in the GC by the spiral drilling in addition to the focus position movement of the UV laser for press mold die of the MNA. After the FIB process, we were able to make the needle die of surface and hole wall roughness less than 0.9 μm. A silicon rubber is used to confirm the shape of the holes.