Changes in In-Hospital Survival and Long-Term Neurodevelopmental Outcomes of Extremely Preterm Infants: A Retrospective Study of a Japanese Tertiary Center.

OBJECTIVES: The objective of this study was to elucidate whether the survival and long-term neurodevelopmental outcomes of extremely preterm infants have improved in a Japanese tertiary center with an active treatment policy for infants born at 22-23 weeks of gestation. STUDY DESIGN: This single-centered retrospective cohort study enrolled extremely preterm infants treated at Saitama Medical Center, Saitama Medical University, from 2003 to 2014. Patients with major congenital abnormalities were excluded. Primary outcomes were in-hospital survival and severe neurodevelopmental impairment (NDI) at 6 years of age, which was defined as having severe cerebral palsy, severe cognitive impairment, severe visual impairment, or deafness. We assessed the changes in primary outcomes between the first (period 1; 2003-2008) and the second half (period 2; 2009-2014) of the study period and evaluated the association between birth-year and primary outcomes using multivariate logistic regression models. RESULTS: Of the 403 eligible patients, 340 (84%) survived to discharge. Among 248 patients available at 6 years of age, 43 (14%) were classified as having severe NDI. Between the 2 periods, in-hospital survival improved from 155 of 198 (78%) to 185 of 205 (90%), but severe NDI increased from 11 of 108 (10%) to 32 of 140 (23%). In multivariate logistic regression models adjusted for gestational age, birthweight, sex, singleton birth, and antenatal corticosteroids, the aOR (95% CI) of birth-year for in-hospital survival and severe NDI was 1.2 (1.1-1.3) and 1.1 (1.0-1.3), respectively. CONCLUSION: Mortality among extremely preterm infants has improved over the past 12 years; nevertheless, no significant improvement was observed in the long-term neurodevelopmental outcomes.

Differential roles of epigenetic regulators in the survival and differentiation of oligodendrocyte precursor cells.

During development or after brain injury, oligodendrocyte precursor cells (OPCs) differentiate into oligodendrocytes to supplement the number of oligodendrocytes. Although mechanisms of OPC differentiation have been extensively examined, the role of epigenetic regulators, such as histone deacetylases (HDACs) and DNA methyltransferase enzymes (DNMTs), in this process is still mostly unknown. Here, we report the differential roles of epigenetic regulators in OPC differentiation. We prepared primary OPC cultures from neonatal rat cortex. Our cultured OPCs expressed substantial amounts of mRNA for HDAC1, HDAC2, DNMT1, and DNMT3a. mRNA levels of HDAC1 and HDAC2 were both decreased by the time OPCs differentiated into myelin-basic-protein expressing oligodendrocytes. However, DNMT1 or DNMT3a mRNA level gradually decreased or increased during the differentiation step, respectively. We then knocked down those regulators in cultured OPCs with siRNA technique before starting OPC differentiation. While HDAC1 knockdown suppressed OPC differentiation, HDAC2 knockdown promoted OPC differentiation. DNMT1 knockdown also suppressed OPC differentiation, but unlike HDAC1/2, DNMT1-deficient cells showed cell damage during the later phase of OPC differentiation. On the other hand, when OPCs were transfected with siRNA for DNMT3a, the number of OPCs was decreased, indicating that DNMT3a may participate in OPC survival/proliferation. Taken together, these data demonstrate that each epigenetic regulator has different phase-specific roles in OPC survival and differentiation.

A-Kinase Anchor Protein 12 Is Required for Oligodendrocyte Differentiation in Adult White Matter.

Oligodendrocyte precursor cells (OPCs) give rise to oligodendrocytes in cerebral white matter. However, the underlying mechanisms that regulate this process remain to be fully defined, especially in adult brains. Recently, it has been suggested that signaling via A-kinase anchor protein 12 (AKAP12), a scaffolding protein that associates with intracellular molecules such as protein kinase A, may be involved in Schwann cell homeostasis and peripheral myelination. Here, we asked whether AKAP12 also regulates the mechanisms of myelination in the CNS. AKAP12 knockout mice were compared against wild-type (WT) mice in a series of neurochemical and behavioral assays. Compared with WTs, 2-months old AKAP12 knockout mice exhibited loss of myelin in white matter of the corpus callosum, along with perturbations in working memory as measured by a standard Y-maze test. Unexpectedly, very few OPCs expressed AKAP12 in the corpus callosum region. Instead, pericytes appeared to be one of the major AKAP12-expressing cells. In a cell culture model system, conditioned culture media from normal pericytes promoted in-vitro OPC maturation. However, conditioned media from AKAP12-deficient pericytes did not support the OPC function. These findings suggest that AKAP12 signaling in pericytes may be required for OPC-to-oligodendrocyte renewal to maintain the white matter homeostasis in adult brain. Stem Cells 2018;36:751-760.

Astrocytes Promote Oligodendrogenesis after White Matter Damage via Brain-Derived Neurotrophic Factor.

Oligodendrocyte precursor cells (OPCs) in the adult brain contribute to white matter homeostasis. After white matter damage, OPCs compensate for oligodendrocyte loss by differentiating into mature oligodendrocytes. However, the underlying mechanisms remain to be fully defined. Here, we test the hypothesis that, during endogenous recovery from white matter ischemic injury, astrocytes support the maturation of OPCs by secreting brain-derived neurotrophic factor (BDNF). For in vitro experiments, cultured primary OPCs and astrocytes were prepared from postnatal day 2 rat cortex. When OPCs were subjected to chemical hypoxic stress by exposing them to sublethal CoCl2 for 7 d, in vitro OPC differentiation into oligodendrocytes was significantly suppressed. Conditioned medium from astrocytes (astro-medium) restored the process of OPC maturation even under the stressed conditions. When astro-medium was filtered with TrkB-Fc to remove BDNF, the BDNF-deficient astro-medium no longer supported OPC maturation. For in vivo experiments, we analyzed a transgenic mouse line (GFAP(cre)/BDNF(wt/fl)) in which BDNF expression is downregulated specifically in GFAP(+) astrocytes. Both wild-type (GFAP(wt)/BDNF(wt/fl) mice) and transgenic mice were subjected to prolonged cerebral hypoperfusion by bilateral common carotid artery stenosis. As expected, compared with wild-type mice, the transgenic mice exhibited a lower number of newly generated oligodendrocytes and larger white matter damage. Together, these findings demonstrate that, during endogenous recovery from white matter damage, astrocytes may promote oligodendrogenesis by secreting BDNF. SIGNIFICANCE STATEMENT: The repair of white matter after brain injury and neurodegeneration remains a tremendous hurdle for a wide spectrum of CNS disorders. One potentially important opportunity may reside in the response of residual oligodendrocyte precursor cells (OPCs). OPCs may serve as a back-up for generating mature oligodendrocytes in damaged white matter. However, the underlying mechanisms are still mostly unknown. Here, we use a combination of cell biology and an animal model to report a new pathway in which astrocyte-derived BDNF supports oligodendrogenesis and regeneration after white matter damage. These findings provide new mechanistic insight into white matter physiology and pathophysiology, which would be broadly and clinically applicable to CNS disease.

Astrocyte-Derived Pentraxin 3 Supports Blood-Brain Barrier Integrity Under Acute Phase of Stroke.

BACKGROUND AND PURPOSE: Pentraxin 3 (PTX3) is released on inflammatory responses in many organs. However, roles of PTX3 in brain are still mostly unknown. Here we asked whether and how PTX3 contributes to blood-brain barrier dysfunction during the acute phase of ischemic stroke. METHODS: In vivo, spontaneously hypertensive rats were subjected to focal cerebral ischemia by transient middle cerebral artery occlusion. At day 3, brains were analyzed to evaluate the cellular origin of PTX3 expression. Correlations with blood-brain barrier breakdown were assessed by IgG staining. In vitro, rat primary astrocytes and rat brain endothelial RBE.4 cells were cultured to study the role of astrocyte-derived PTX3 on vascular endothelial growth factor-mediated endothelial permeability. RESULTS: During the acute phase of stroke, reactive astrocytes in the peri-infarct area expressed PTX3. There was negative correlation between gradients of IgG leakage and PTX3-positive astrocytes. Cell culture experiments showed that astrocyte-conditioned media increased levels of tight junction proteins and reduced endothelial permeability under normal conditions. Removing PTX3 from astrocyte-conditioned media by immunoprecipitation increased endothelial permeability. PTX3 strongly bound vascular endothelial growth factor in vitro and was able to decrease vascular endothelial growth factor-induced endothelial permeability. CONCLUSIONS: Astrocytes in peri-infarct areas upregulate PTX3, which may support blood-brain barrier integrity by regulating vascular endothelial growth factor-related mechanisms. This response in astrocytes may comprise a compensatory mechanism for maintaining blood-brain barrier function after ischemic stroke.

Neuregulin1-ß decreases interleukin-1ß-induced RhoA activation, myosin light chain phosphorylation, and endothelial hyperpermeability.

Neuregulin-1 (NRG1) is an endogenous growth factor with multiple functions in the embryonic and postnatal brain. The NRG1 gene is large and complex, transcribing more than twenty transmembrane proteins and generating a large number of isoforms in tissue and cell type-specific patterns. Within the brain, NRG1 functions have been studied most extensively in neurons and glia, as well as in the peripheral vasculature. Recently, NRG1 signaling has been found to be important in the function of brain microvascular endothelial cells, decreasing IL-1ß-induced increases in endothelial permeability. In the current experiments, we have investigated the pathways through which the NRG1-ß isoform acts on IL-1ß-induced endothelial permeability. Our data show that NRG1-ß increases barrier function, measured by transendothelial electrical resistance, and decreases IL-1ß-induced hyperpermeability, measured by dextran-40 extravasation through a monolayer of brain microvascular endothelial cells plated on transwells. An investigation of key signaling proteins suggests that the effect of NRG1-ß on endothelial permeability is mediated through RhoA activation and myosin light chain phosphorylation, events which affect filamentous actin morphology. In addition, AG825, an inhibitor of the erbB2-associated tyrosine kinase, reduces the effect of NRG1-ß on IL-1ß-induced RhoA activation and myosin light chain phosphorylation. These data add to the evidence that NRG1-ß signaling affects changes in the brain microvasculature in the setting of neuroinflammation. We propose the following events for neuregulin-1-mediated effects on Interleukin-1 ß (IL-1ß)-induced endothelial hyperpermeability: IL-1ß leads to RhoA activation, resulting in an increase in phosphorylation of myosin light chain (MLC). Phosphorylation of MLC is known to result in actin contraction and alterations in the f-actin cytoskeletal structure. These changes are associated with increased endothelial permeability. Neuregulin-1ß acts through its transmembrane receptors to activate intracellular signaling pathways which inhibit IL-1ß-induced RhoA activation and MLC phosphorylation, thereby preserving the f-actin cytoskeletal structure and endothelial barrier function.

Skin blood flow as a predictor of intraventricular hemorrhage in very-low-birth-weight infants.

BACKGROUND: Cardiovascular instability immediately after birth is associated with intraventricular hemorrhage (IVH) in very-low-birth-weight (VLBW) infants. For circulatory management, evaluation of organ blood flow is important. In this study, the relationship between peripheral perfusion within 48 h after birth and IVH was evaluated in VLBW infants. METHODS: In this prospective observational study involving 83 VLBW infants, forehead blood flow (FBF) and lower-limb blood flow (LBF) were measured for 48 h after birth using a laser Doppler flowmeter. Blood flow was compared between infants with and without IVH. Multivariate logistic regression analysis was performed to identify the risk factors for IVH. RESULTS: IVH developed in nine infants. In eight of these patients, IVH occurred after 24 h. LBF was lower in infants with IVH at 18 and 24 h and increased to the same level as that of infants without IVH at 48 h. Multivariate logistic regression analysis identified a correlation only between LBF and IVH at 18 h. CONCLUSION: These findings were consistent with the hypoperfusion-reperfusion theory, which states that IVH develops after reperfusion subsequent to hypoperfusion. We speculate that measurement of skin blood flow in addition to systemic and cerebral circulation may be helpful in predicting IVH.

Predictability of the neurodevelopmental assessment based on the Kyoto Scale of Psychological Development 2001 at 18-24 months of corrected age and 3 years of age in identifying cognitive impairment at 6 years of age in very preterm infants: A retrospective study at a Japanese tertiary center.

BACKGROUND: It is unknown how accurately the current Japanese classification system for neurodevelopmental delay based on the assessment with the Kyoto Scale of Psychological Development (KSPD) at toddlerhood and pre-school periods predicts cognitive impairment at school age. METHODS: This single-center retrospective cohort study enrolled infants born at 22-29 weeks of gestational age. At 18-24 months of corrected age and 3 years of age, the patients were categorized according to the current Japanese criteria for neurodevelopmental delay based on their overall developmental quotient calculated using the KSPD-2001. Cognitive impairment at 6 years of age was classified according to the calculated or estimated full-scale intelligence quotient. The predictability of the current Japanese classification of neurodevelopmental delay for cognitive impairment at 6 years of age was investigated. RESULTS: Of 566 eligible patients, 364 (64 %) completed the protocol. The current classification for the neurodevelopmental delay showed significant agreement with the severity of cognitive impairment at 6 years of age. The sensitivity and specificity of the KSPD-2001-based assessment for any cognitive impairment at 6 years of age were 0.64 and 0.74 at 18-24 months of corrected age and 0.83 and 0.70 at 3 years of age. The corresponding sensitivity and specificity for moderate/severe cognitive impairment were 0.51 and 0.96 at 18-24 months of corrected age and 0.68 and 0.95 at 3 years of age. CONCLUSION: The KSPD-2001 is a useful tool to predict the severity of cognitive impairment at school age.

Prolonged oligohydramnios and the adverse composite outcome of death or severe neurodevelopmental impairment at 3 years of age in infants born at 22-29 gestational weeks.

OBJECTIVE: To investigate the association between prolonged oligohydramnios and a composite outcome of death or severe neurodevelopmental impairment (NDI) at 3 years of age. METHODS: This single-center retrospective cohort study enrolled infants born at 22-29 weeks of gestational age without major congenital anomalies. The patients were classified into three groups depending on the existence and duration of oligohydramnios: no/non-prolonged oligohydramnios (no or 0-7 days of oligohydramnios), prolonged oligohydramnios (8-14 days), and very prolonged oligohydramnios (> 14 days). The primary outcome was a composite of death or severe NDI, which was defined as severe cerebral palsy, developmental delay, severe visual impairment, or deafness at age 3. RESULTS: Out of the 843 patients, 784 (93 %), 30 (3.6 %), and 29 (3.4 %) were classified into the no/non-prolonged, prolonged, and very prolonged oligohydramnios groups, respectively. After excluding patients lost to follow-up, the adverse composite outcome at 3 years of age was observed in 194/662 (29 %), 7/26 (27 %), and 8/23 (35 %) in the corresponding groups. The composite outcome showed no significant trend with the duration of oligohydramnios (P = 0.70). In a logistic regression model controlling the known predictors of gestational age, birth weight, small-for-gestational-age, male sex, multiple pregnancy, hypertensive disorders of pregnancy, antenatal corticosteroids, and the number of family-social risk factors, the duration of oligohydramnios was not independently associated with the composite outcome; odds ratio 1.3 (95 % confidence interval, 0.78-2.0). CONCLUSION: Prolonged oligohydramnios was not associated with the composite outcome of death or severe NDI at 3 years of age.

An Extremely Preterm Infant Born at 23 Weeks' Gestation With an Interrupted Aortic Arch Complex: A Case Report.

We present a case of an infant male born at 23 weeks' gestation with an interrupted aortic arch (IAA) complex. We treated the patient with hypoxic gas ventilation to address developing systemic undercirculation in the acute postnatal phase. As the symptoms of bronchopulmonary dysplasia evolved, hypoxic gas ventilation was no longer required to stabilize the hemodynamics. The patient was discharged home after undergoing the palliative surgical procedure of bilateral pulmonary artery banding and ductus arteriosus stent implantation. Although he suffered from pulmonary hypertension, it was controllable with oxygen supplementation and pulmonary vasodilators. There are limited therapeutic options available for extremely preterm infants with critical congenital heart defects (CHDs). Hypoxic gas ventilation might be considered as one of the options, with its risks taken into account, to manage extremely preterm infants with CHDs with pulmonary overcirculation before performing surgical interventions.

Effect of dopamine on peripheral perfusion in very-low-birth-weight infants during the transitional period.

INTRODUCTION: Dopamine is one of the most frequently used inotropic drugs in neonatal intensive care units (NICUs); however, it does not seem to improve outcomes in premature infants. Given that the ultimate aim of cardiovascular management is to stabilize and maintain organ perfusion, an understanding of dopamine's effects on organ blood flow will help in judging when to use dopamine and how to titrate the dosage. Such an approach can lead to improved outcomes. This study aimed to evaluate the effects of dopamine on peripheral perfusion in very-low-birth-weight (VLBW) infants within 72 h of birth. METHODS: This prospective observational study identified and sampled 44 instances of initiation of dopamine treatment or increase in dopamine dose in 29 VLBW infants. Blood pressure, heart rate, and skin and subcutaneous blood flow were measured and compared before and after each instance. RESULTS: Blood pressure and skin and subcutaneous blood flow in the lower limbs increased after initiation of dopamine treatment or after dose increase. DISCUSSION: Dopamine increases blood pressure as well as skin and subcutaneous blood flow in VLBW infants despite its supposed vasoconstrictive action, indicating that it increases both perfusion pressure and blood flow and is devoid of overwhelming peripheral vasoconstrictive effects.

Prophylactic probiotics reduce cow's milk protein intolerance in neonates after small intestine surgery and antibiotic treatment presenting symptoms that mimics postoperative infection.

BACKGROUND: To examine occurrence of cow's milk protein intolerance (CMPI) in newborns that underwent small intestine surgery and the clinical profiles of those newborns with postoperative CMPI, and to evaluate the preventive effects of probiotics on CMPI. METHODS: We retrospectively reviewed from 2000 to 2009, a total of 30 newborns required surgery on their small intestines. All of these patients had received antibiotics to prevent postoperative infection. Since 2005 we adopted a protocol of targeted probiotic therapy prophylaxis. RESULTS: Eighteen patients received probiotic therapy, while twelve did not. One infant among those eighteen patients and eight patients among those twelve developed CMPI, a significantly lower rate for the group with probiotic therapy than that without it (p < 0.001). Patients with positive cultures for gram positive and gram negative organisms increased in number before and after surgery but then decreased after probiotics treatment. Poor weight gain, gastrointestinal symptoms, and rise in C reactive protein (CRP) levels were observed in all of those nine CMPI patients. Specific IgE antibodies were elevated in four of the nine subjects, and total IgE levels were elevated in seven of them. All CMPI patients had increased level of CRP without proven infections. CONCLUSIONS: CMPI was induced in newborns after surgery on their small intestines and antibiotics treatment with presentation of symptoms that mimic postoperative infection. Development of CMPI in this population possibly involves disruption of intestinal flora. Administration of probiotics can reduce the incidence of CMPI after small intestine surgery. The elevated CRP level may be useful in the diagnosis of CMPI.

Severe Consumptive Coagulopathy in an Extremely-Low-Birth-Weight Infant with Intra-Abdominal Umbilical Vein Varix: A Case Report.

Recent studies have shown favorable outcomes for intra-abdominal umbilical vein varices (IUVVs) in term neonates who have no other complications. Little is known, however, about the prognosis of IUVVs in preterm neonates. We encountered a case of IUVV in an extremely low-birth-weight infant who developed severe consumptive coagulopathy after birth. The patient's coagulation test normalized as the varix spontaneously obstructed. Although life-threatening hemorrhagic complications were avoided, a cerebellum hemorrhage was found in the brain magnetic resonance imaging at the term-equivalent age. In a literature survey, coagulopathy was reported in 4 out of 15 infants with IUVVs born before 34 weeks of gestation, including our present case. Preterm infants with IUVVs may develop coagulopathy because of the prematurity of their coagulation-fibrinolysis systems. Attention should be given to the coagulation status of preterm neonates with IUVVs.

Occipitosacral Fusion for Multiple Vertebral Fractures with Kyphotic Deformity in a Patient with Mutilating Rheumatoid Arthritis: A Case Report.

Osteoporotic vertebral fractures are well-known complications of rheumatoid arthritis. The management of multiple vertebral fractures with kyphotic deformity is controversial. We present a case of a patient with mutilating rheumatoid arthritis who had multiple vertebral fractures with kyphotic deformity after occipitothoracic fusion for rheumatoid cervical disorder. Occipitosacral fusion was effective to create stable spine with better sagittal alignment in this case, but careful clinical assessment for early detection and management of postoperative insufficient pelvic fracture were required.

A Novel Three-Dimensional Culture System for Oligodendrocyte Precursor Cells.

Oligodendrocytes are generated from oligodendrocyte precursor cells (OPCs). Mechanisms of OPC differentiation have been extensively examined with two-dimensional cell culture systems. However, these cellular events may be more accurately represented using a three-dimensional (3D) model. In this study, we report the development of a novel 3D OPC culture system using gels composed of a mixture of collagen and hyaluronan, wherein cultured rat primary OPCs can proliferate and differentiate into oligodendrocytes. Our data show that the gel concentration and cell-seeding density are critical factors for the numbers of OPCs and oligodendrocytes in our 3D culture system. In addition, Notch signaling, which supports cell-to-cell communication, may also be important for OPC function in our system because a Notch inhibitor DAPT suppressed OPC proliferation and differentiation. Taken together, cultured rat OPCs can grow in collagen-/hyaluronan-based gels, and our novel 3D OPC culture system may offer a useful platform for examining the mechanisms of OPC function in vitro.

Magnesium sulfate protects oligodendrocyte lineage cells in a rat cell-culture model of hypoxic-ischemic injury.

Hypoxic-ischemic (HI) brain injury in newborns results in serious damage. Magnesium sulfate has been clinically used as a cyto-protective agent against HI brain injury in newborns in some countries, including Japan. However, it is not clear how magnesium exerts this effect and how it acts on the individual types of cells within the newborn brain. In this study, we exposed cultured rat oligodendrocyte precursor cells to magnesium sulfate during the period when they differentiate into oligodendrocytes, and showed that magnesium-exposed oligodendrocytes exhibited more resistance to HI injury. Our data may support the use of magnesium sulfate in the clinical setting.

Effects of Aging on Neural Stem/Progenitor Cells and Oligodendrocyte Precursor Cells After Focal Cerebral Ischemia in Spontaneously Hypertensive Rats.

Aging and vascular comorbidities such as hypertension comprise critical cofactors that influence how the brain responds to stroke. Ischemic stress induces neurogenesis and oligodendrogenesis in younger brains. However, it remains unclear whether these compensatory mechanisms can be maintained even under pathologically hypertensive and aged states. To clarify the age-related remodeling capacity after stroke under hypertensive conditions, we assessed infarct volume, behavioral outcomes, and surrogate markers of neurogenesis and oligodendrogenesis in acute and subacute phases after transient focal cerebral ischemia in 3- and 12-month-old spontaneously hypertensive rats (SHRs). Hematoxylin and eosin staining showed that 3- and 12-month-old SHRs exhibited similar infarction volumes at both 3 and 14 days after focal cerebral ischemia. However, recovery of behavioral deficits (neurological score assessment and adhesive removal test) was significantly less in 12-month-old SHRs compared to 3-month-old SHRs. Concomitantly, numbers of nestin(+) neural stem/progenitor cells (NSPCs) near the infarct border area or subventricular zone in 12-month-old SHRs were lower than 3-month-old SHRs at day 3. Similarly, numbers of PDGFR-α(+) oligodendrocyte precursor cells (OPCs) in the corpus callosum were lower in 12-month-old SHRs at day 3. Lower levels of NSPC and OPC numbers were accompanied by lower expression levels of phosphorylated CREB. By day 14 postischemia, NSPC and OPC numbers in 12-month-old SHRs recovered to similar levels as in 3-month-old SHRs, but the numbers of proliferating NSPCs (Ki-67(+)nestin(+) cells) and proliferating OPCs (Ki-67(+)PDGFR-α(+) cells) remained lower in the older brains even at day 14. Taken together, these findings suggest that aging may also decrease poststroke compensatory responses for neurogenesis and oligodendrogenesis even under hypertensive conditions.

No association of the brain-derived neurotrophic factor (BDNF) gene polymorphisms with panic disorder.

Several lines of evidence suggest that genetic factors might contribute to susceptibility to panic disorder. Our previous studies show that the brain-derived neurotrophic factor (BDNF) may play a role in the pathophysiology of major depressive disorders and eating disorders. Assuming that BDNF may be implicated in the putative common pathophysiology of depression and anxiety, we analyzed the association of two BDNF gene single nucleotide polymorphisms (SNPs), 132C > T (formerly named C270T) in the noncoding region of exon V and 196G > A (val66met) in the coding region of exon XIIIA, with panic disorder. In this study, 109 patients with panic disorder diagnosed according to the DSM-IV criteria, and 178 control subjects were recruited. There were no significant differences in the frequency of the genotype or allele in these two SNPs between patients and controls [132C > T in exon V: genotype, p = 1.0, allele, p = 0.59; 196G > A (val66met) in exon XIIIA: genotype, p = 0.77, allele, p = 0.78]. Furthermore, no significant associations of agoraphobia with the two SNPs were detected. This study suggests that the BDNF gene polymorphisms are not associated with panic disorder in our Japanese population.

Mechanisms of cell-cell interaction in oligodendrogenesis and remyelination after stroke.

White matter damage is a clinically important aspect of several central nervous system diseases, including stroke. Cerebral white matter primarily consists of axonal bundles ensheathed with myelin secreted by mature oligodendrocytes, which play an important role in neurotransmission between different areas of gray matter. During the acute phase of stroke, damage to oligodendrocytes leads to white matter dysfunction through the loss of myelin. On the contrary, during the chronic phase, white matter components promote an environment, which is favorable for neural repair, vascular remodeling, and remyelination. For effective remyelination to take place, oligodendrocyte precursor cells (OPCs) play critical roles by proliferating and differentiating into mature oligodendrocytes, which help to decrease the burden of axonal injury. Notably, other types of cells contribute to these OPC responses under the ischemic conditions. This mini-review summarizes the non-cell autonomous mechanisms in oligodendrogenesis and remyelination after white matter damage, focusing on how OPCs receive support from their neighboring cells. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.

Distal Junctional Disease after Occipitothoracic Fusion for Rheumatoid Cervical Disorders: Correlation with Cervical Spine Sagittal Alignment.

Study Design Retrospective radiographic study. Objective We have performed occipitothoracic (OT) fusion for severe rheumatoid cervical disorders since 1991. In our previous study, we reported that the distal junctional disease occurred in patients with fusion of O-T4 or longer due to increased mechanical stress. The present study further evaluated the association between the distal junctional disease and the cervical spine sagittal alignment. Methods Among 60 consecutive OT fusion cases between 1991 and 2010, 24 patients who underwent O-T5 fusion were enrolled in this study. The patients were grouped based on whether they developed postoperative distal junctional disease (group F) or not (group N). We measured pre- and postoperative O-C2, C2-C7, and O-C7 angles and evaluated the association between these values and the occurrence of distal junctional disease. Results Seven (29%) of 24 patients developed adjacent-level vertebral fractures as distal junctional disease. In group F, the mean pre- and postoperative O-C2, C2-C7, and O-C7 angles were 12.1 and 16.8, 7.2 and 11.2, and 19.4 and 27.9 degrees, respectively. In group N, the mean pre- and postoperative O-C2, C2-C7, and O-C7 angles were 15.9 and 15.0, 4.9 and 5.8, and 21.0 and 20.9 degrees, respectively. There were no significant differences between the two groups. The difference in the O-C7 angle (postoperative angle - preoperative angle) in group F was significantly larger than that in group N (p = 0.04). Conclusion Excessive correction of the O-C7 angle (hyperlordotic alignment) is likely to cause postoperative distal junctional disease following the OT fusion.