Granulocyte macrophage colony-stimulating factor-induced macrophages of individuals with autism spectrum disorder adversely affect neuronal dendrites through the secretion of pro-inflammatory cytokines

BACKGROUND

A growing body of evidence suggests that immune dysfunction and inflammation in the peripheral tissues as well as the central nervous system are associated with the neurodevelopmental deficits observed in autism spectrum disorder (ASD). Elevated expression of pro-inflammatory cytokines in the plasma, serum, and peripheral blood mononuclear cells of ASD has been reported. These cytokine expression levels are associated with the severity of behavioral impairments and symptoms in ASD. In a prior study, our group reported that tumor necrosis factor-α (TNF-α) expression in granulocyte-macrophage colony-stimulating factor-induced macrophages (GM-CSF MΦ) and the TNF-α expression ratio in GM-CSF MΦ/M-CSF MΦ (macrophage colony-stimulating factor-induced macrophages) was markedly higher in individuals with ASD than in typically developed (TD) individuals. However, the mechanisms of how the macrophages and the highly expressed cytokines affect neurons remain to be addressed.

METHODS

To elucidate the effect of macrophages on human neurons, we used a co-culture system of control human-induced pluripotent stem cell-derived neurons and differentiated macrophages obtained from the peripheral blood mononuclear cells of five TD individuals and five individuals with ASD. All participants were male and ethnically Japanese.

RESULTS

Our results of co-culture experiments showed that GM-CSF MΦ affect the dendritic outgrowth of neurons through the secretion of pro-inflammatory cytokines, interleukin-1α and TNF-α. Macrophages derived from individuals with ASD exerted more severe effects than those derived from TD individuals.

LIMITATIONS

The main limitations of our study were the small sample size with a gender bias toward males, the use of artificially polarized macrophages, and the inability to directly observe the interaction between neurons and macrophages from the same individuals.

CONCLUSIONS

Our co-culture system revealed the non-cell autonomous adverse effects of GM-CSF MΦ in individuals with ASD on neurons, mediated by interleukin-1α and TNF-α. These results may support the immune dysfunction hypothesis of ASD, providing new insights into its pathology.

Brain-derived neurotrophic factor from microglia regulates neuronal development in the medial prefrontal cortex and its associated social behavior

Microglia and brain-derived neurotrophic factor (BDNF) are essential for the neuroplasticity that characterizes critical developmental periods. The experience-dependent development of social behaviors-associated with the medial prefrontal cortex (mPFC)-has a critical period during the juvenile period in mice. However, whether microglia and BDNF affect social development remains unclear. Herein, we aimed to elucidate the effects of microglia-derived BDNF on social behaviors and mPFC development. Mice that underwent social isolation during p21-p35 had increased Bdnf in the microglia accompanied by reduced adulthood sociability. Additionally, transgenic mice overexpressing microglial Bdnf-regulated using doxycycline at different time points-underwent behavioral, electrophysiological, and gene expression analyses. In these mice, long-term overexpression of microglial BDNF impaired sociability and excessive mPFC inhibitory neuronal circuit activity. However, administering doxycycline to normalize BDNF from p21 normalized sociability and electrophysiological function in the mPFC, whereas normalizing BDNF from later ages (p45-p50) did not normalize electrophysiological abnormalities in the mPFC, despite the improved sociability. To evaluate the possible role of BDNF in human sociability, we analyzed the relationship between adverse childhood experiences and BDNF expression in human macrophages, a possible proxy for microglia. Results show that adverse childhood experiences positively correlated with BDNF expression in M2 but not M1 macrophages. In summary, our study demonstrated the influence of microglial BDNF on the development of experience-dependent social behaviors in mice, emphasizing its specific impact on the maturation of mPFC function, particularly during the juvenile period. Furthermore, our results propose a translational implication by suggesting a potential link between BDNF secretion from macrophages and childhood experiences in humans.

Association of adverse childhood experiences and cortical neurite density alterations with posttraumatic stress disorder symptoms in autism spectrum disorder

Background

Posttraumatic stress disorder (PTSD) can be a source of significant social and daily distress in autism spectrum disorder (ASD). Compared to typically developed (TD) individuals, people with ASD are at an increased risk of adverse childhood experiences (ACEs), which can result in abnormal neuronal development. However, whether or how ACEs influence abnormal neural development and PTSD symptoms in ASD has not been fully elucidated.

Methods

Thirty-nine TD individuals and 41 individuals with ASD underwent T1-weighted magnetic resonance imaging and neurite orientation dispersion and density imaging (NODDI), with axonal and dendritic densities assessed in terms of the orientation dispersion index and neurite density index (NDI), respectively. Voxel-based analyses were performed to explore the brain regions associated with PTSD symptoms, and the relationships between the severity of ACEs and PTSD symptoms and NODDI parameters in the extracted brain regions were examined.

Results

There was a significant positive association between PTSD symptom severity and NDI in the bilateral supplementary motor area; right superior frontal, left supramarginal, and right superior temporal gyrus; and right precuneus in the ASD group, but not in the TD group. ACE severity was significantly associated with NDI in the right superior frontal and left supramarginal gyrus and right precuneus in the ASD group. Moreover, NDI in the right precuneus mainly predicted the severity of PTSD symptoms in the ASD group, but not the TD group.

Conclusion

These results suggest that ACE-associated higher neurite density is of clinical importance in the pathophysiology of PTSD symptoms in ASD.

Brain-derived neurotrophic factor from microglia regulates neuronal development in the medial prefrontal cortex and its associated social behavior

Microglia and brain-derived neurotrophic factor (BDNF) are essential for the neuroplasticity that characterizes critical developmental periods. The experience-dependent development of social behaviors-associated with the medial prefrontal cortex (mPFC)-has a critical period during the juvenile period in mice. However, whether microglia and BDNF affect social development remains unclear. Herein, we aimed to elucidate the effects of microglia-derived BDNF on social behaviors and mPFC development. Mice that underwent social isolation during p21-p35 had increased Bdnf in the microglia accompanied by reduced adulthood sociability. Additionally, transgenic mice overexpressing microglia Bdnf-regulated using doxycycline at different time points-underwent behavioral, electrophysiological, and gene expression analyses. In these mice, long-term overexpression of microglia BDNF impaired sociability and excessive mPFC inhibitory neuronal circuit activity. However, administration of doxycycline to normalize BDNF from p21 normalized sociability and electrophysiological functions; this was not observed when BDNF was normalized from a later age (p45-p50). To evaluate the possible role of BDNF in human sociability, we analyzed the relationship between adverse childhood experiences and BDNF expression in human macrophages, a possible substitute for microglia. Results show that adverse childhood experiences positively correlated with BDNF expression in M2 but not M1 macrophages. Thus, microglia BDNF might regulate sociability and mPFC maturation in mice during the juvenile period. Furthermore, childhood experiences in humans may be related to BDNF secretion from macrophages.

Association of adverse childhood experience-related increase in neurite density with sensory over-responsivity in autism spectrum disorder: A neurite orientation dispersion and density imaging study

Sensory over-responsivity (SOR) causes social and daily distress in individuals with autism spectrum disorder (ASD). Compared to typically developed (TD) individuals, ASD individuals are at higher risk of adverse childhood experiences (ACEs), which induce abnormal neuronal development. However, whether or how ACEs are associated with abnormal neural development and SOR in ASD remains to be determined. Forty-five individuals with ASD and 43 TD individuals underwent T1-weighted and neurite orientation dispersion and density imaging; the axonal and dendritic densities were defined as the neurite density index (NDI). Voxel-based analyses were performed to explore the brain regions associated with SOR. The relationships between severity of ACEs and SOR, and NDI in the brain regions were examined. ASD individuals showed a significantly positive association between SOR severity and NDI in the right superior temporal gyrus (STG), which was not found in TD individuals. Severity of ACEs correlated significantly with that of SOR and NDI in the right STG in ASD; ASD individuals having severe SOR showed significantly higher NDI in the right STG than those with mild SOR and TD individuals. In individuals with ASD, NDI in the right STG, but not ACEs, could predict the severity of SOR, which was not shown in TD subjects. Our findings suggest that severe ACEs are involved in excessive neurite density in the right STG in ASD. ACE-associated excessive neurite density in the right STG is critical for SOR in ASD, which may be a therapeutic target in the future.

Tumor necrosis factor-α expression aberration of M1/M2 macrophages in adult high-functioning autism spectrum disorder

The etiology of autism spectrum disorder (ASD) is complex, and its pathobiology is characterized by enhanced inflammatory activities; however, the precise pathobiology and underlying causes of ASD remain unclear. This study was performed to identify inflammatory indicators useful for diagnosing ASD. The mRNA expression of cytokines, including tumor necrosis factor-α (TNF-α), was measured in cultured M1 and M2 macrophages from patients with ASD (n = 29) and typically developed (TD) individuals (n = 30). Additionally, TNF-α expression in the monocytes of patients with ASD (n = 7), showing aberrations in TNF-α expression in M1/M2 macrophages and TD individuals (n = 6), was measured. TNF-α expression in M1 macrophages and the TNF-α expression ratio in M1/M2 macrophages were markedly higher in patients with ASD than in TD individuals; however, this increase was not observed in M2 macrophages (M1: sensitivity = 34.5%, specificity = 96.7%, area under the curve = 0.74, positive likelihood ratio = 10.34; ratio of M1/M2: sensitivity = 55.2%, specificity = 96.7%, area under the curve = 0.79, positive likelihood ratio = 16.55). Additionally, TNF-α expression in monocytes did not significantly differ between patients with ASD and TD individuals. In conclusion, further studies on TNF-α expression in cultured macrophages may improve the understanding of ASD pathobiology. LAY SUMMARY: TNF-α expression in differentiated M1 macrophages and TNF-α expression ratio in differentiated M1/M2 macrophages were markedly higher in patients with ASD than in TD individuals, while no difference in TNF-α expression was found in pre-differentiation cells such as monocytes. These measurements allow elucidation of the novel pathobiology of ASD and can contribute to biomarker implementation for the diagnosis of adult high-functioning ASD.

Association of adverse childhood experiences and precuneus volume with intrusive reexperiencing in autism spectrum disorder

Compared to typically developing (TD) children, people with autism spectrum disorder (ASD) have an increased risk of adverse childhood experiences (ACEs). Exposure to ACEs is associated with adult ASD psychological comorbidities, such as posttraumatic stress disorder (PTSD). Occurrence of intrusive event reexperiencing, characteristic of PTSD, often causes social dysfunction in adults with ASD, but its pathological basis is unclear. This study examined brain regions related to the severity of intrusive reexperiencing and explored whether ACE severity was associated with that of intrusive reexperiencing and/or extracted regional gray matter volume. Forty-six individuals with ASD and 41 TD subjects underwent T1-weighted magnetic resonance imaging and evaluation of ACEs and intrusive reexperiencing. Brain regions related to the severity of intrusive reexperiencing in both groups were identified by voxel-based whole brain analyses. Associations among the severity of intrusive reexperiencing, that of ACEs, and gray matter volume were examined in both groups. The severities of intrusive reexperiencing and ACEs were significantly associated with reduced gray matter volume in the right precuneus in individuals with ASD but not in TD subjects. Although the right precuneus gray matter volume was smaller in individuals with ASD and severe ACEs than in those with mild ACEs or TD subjects, it was similar in the latter two groups. However, ACE-dependent gray matter volume reduction in the right precuneus led to intrusive reexperiencing in individuals with ASD. This suggests that exposure to ACEs is associated with right precuneus gray matter reduction, which is critical for intrusive reexperiencing in adults with ASD. LAY SUMMARY: Individuals with autism spectrum disorder (ASD) are at increased risk of adverse childhood experiences (ACEs) and of subsequent manifestation of intrusive reexperiencing of stressful life events. The present study found that reduced gray matter volume in the right precuneus of the brain was associated with more severe intrusive reexperiencing of ACEs by individuals with ASD. These results suggest that ACEs affect neural development in the precuneus, which is the pathological basis of intrusive event reexperiencing in ASD.

Adverse Childhood Experience Is Associated With Disrupted White Matter Integrity in Autism Spectrum Disorder: A Diffusion Tensor Imaging Study

Individuals with autism spectrum disorder (ASD) have an increased risk of adverse childhood experiences (ACEs) than typically developed (TD) children. Since multiple lines of studies have suggested that ACEs are related to myelination in the frontal lobe, an exposure to ACEs can be associated with white matter microstructural disruption in the frontal lobe, which may be implicated in subsequential psychological deficits after the adulthood. In this study, we investigated the relationship between ACEs and microstructural integrity on frontal lobe-related white matter tracts using diffusion tensor imaging in 63 individuals with ASD and 38 TD participants. Using a tractography-based analysis, we delineated the uncinate fasciculus (UF), dorsal cingulum (Ci), and anterior thalamic radiation (ATR), which are involved in the neural pathology of ASD, and estimated each diffusion parameter. Compared to the TD participants, individuals with ASD displayed significantly lower fractional anisotropy (FA) and higher radial diffusivity (RD) in the left ATR. Then, ASD individuals exposed to severe ACEs displayed higher RD than those exposed to mild ACEs and TD participants in the left ATR. Moreover, the severity of ACEs, particularly neglect, correlated with lower FA and higher RD in the left UF and ATR in individuals with ASD, which was not observed in TD participants. These results suggest that an exposure to ACEs is associated with abnormality in the frontal lobe-related white matter in ASD.

Associations of childhood experiences with event-related potentials in adults with autism spectrum disorder

Childhood maltreatment is defined as experiencing of physical, emotional and sexual abuse and neglect in childhood. Maltreatment in childhood leads to substantial psychosocial problems later in life in the general population. Individuals with autism spectrum disorder (ASD) have a higher risk of experiencing stressful and traumatic events, such as maltreatment, during childhood. Although childhood maltreatment reportedly leads to psychosocial problems in adults with ASD, the biological associations between childhood experiences and brain function in this population remain understudied. Here, we evaluated the relationships between childhood experiences and event-related potential (ERP) components during the auditory odd-ball task in adults with ASD (N = 21) and typically developed (TD) individuals (N = 22). We found that the higher the severity of sexual abuse, the larger the amplitude of P300 at Fz, Cz, C3, and C4 in individuals with ASD. Conversely, the severity of child maltreatment was associated with P300 latency at Cz and C3 in TD individuals. Moreover, full IQ was significantly associated with the MMN amplitude at Fz, Cz, C3, and C4 in TD individuals. These findings provide the first evidence that ERPs could be used to study the impacts childhood experiences on the brain of individuals with ASD and that childhood sexual abuse has salient impacts on brain function in this population.

Delayed prefrontal hemodynamic response associated with suicide risk in autism spectrum disorder

Adults diagnosed with Autism spectrum disorder (ASD) are at high risk of experiencing suicidality compared with other clinical groups. Recently, near-infrared spectroscopy (NIRS) studies have investigated the association between frontotemporal functional abnormalities and suicidality in patients with mood disorders. However, whether these prefrontal hemodynamic responses are associated with suicide vulnerability in individuals with ASD remains unclear. Here, we used 24-channel NIRS to examine the characteristics of prefrontal hemodynamic responses during a verbal fluency task in 20 adults with ASD and in age-, sex-, and intelligence quotient-matched healthy controls. In addition, we used Spearman's correlation analysis to identify the relationship between the time-course of prefrontal hemodynamic activation and the current suicide risk in patients with ASD. We found no significant differences between the verbal fluency task-induced prefrontal hemodynamic responses in the ASD vs. control group. However, we found a significant positive correlation between the current suicide risk score and the time-course of prefrontal hemodynamic activation in the ASD group. Thus, the 24-channel NIRS system appears to be useful in assessing suicide risk in individuals with ASD.

Increased Dendritic Orientation Dispersion in the Left Occipital Gyrus is Associated with Atypical Visual Processing in Adults with Autism Spectrum Disorder

In autism spectrum disorder (ASD), the complexity-specific hypothesis explains that atypical visual processing is attributable to selective functional changes in visual pathways. We investigated dendritic microstructures and their associations with functional connectivity (FC). Participants included 28 individuals with ASD and 29 typically developed persons. We explored changes in neurite orientation dispersion and density imaging (NODDI) and brain areas whose FC was significantly correlated with NODDI parameters in the explored regions of interests. Individuals with ASD showed significantly higher orientation dispersion index (ODI) values in the left occipital gyrus (OG) corresponding to the secondary visual cortex (V2). FC values between the left OG and the left middle temporal gyrus (MTG) were significantly negatively correlated with mean ODI values. The mean ODI values in the left OG were significantly positively associated with low registration of the visual quadrants of the Adolescent/Adult Sensory Profile (AASP), resulting in a significant positive correlation with passive behavioral responses of the AASP visual quadrants; additionally, the FC values between the left OG and the left MTG were significantly negatively associated with reciprocal social interaction. Our results suggest that abnormal V2 dendritic arborization is associated with atypical visual processing by altered intermediation in the ventral visual pathway.

Microstructural Anomalies Evaluated by Neurite Orientation Dispersion and Density Imaging Are Related to Deficits in Facial Emotional Recognition via Perceptual-Binding Difficulties in Autism Spectrum Disorder

The integration of visual features is important for recognizing objects as a coherent whole, a key domain of difficulty in autism spectrum disorder (ASD). We tested the hypothesis that ASD patients exhibit difficulties in facial emotional recognition via perceptual binding difficulties due to weak coherence. We assessed 18 ASD and 27 typically developing individuals for their ability to identify emotional expressions from faces in pictures moving behind a narrow vertical and horizontal slit. In this task, only a single local piece of facial information was provided at any one time through the slit. Using a voxel-based analysis of neurite-orientation dispersion and density imaging (NODDI), we examined the relationship between NODDI index values at each voxel and the behavioral performance of ASD patients in the slit-viewing paradigm. ASD patients demonstrated impaired recognition of facial emotional expression only in horizontal slit-viewing. This deficit was associated with deficits in communication ability. Voxel-based analysis revealed significant negative correlations between behavioral deficits in horizontal slit-viewing and NODDI index values in clusters including the ventral occipital complex region, superior temporal/parietal association areas, and forceps major of the corpus callosum. Our results indicated deficits for the first time in perceptual integration of facial expression across hemispheres in ASD patients due to microstructural disturbances in the corpus callosum and areas related to viewing of the human face. This may underscore the difficulties faced by ASD patients in understanding the emotions of other people, contributing to impairments in communication ability in ASD patients. Autism Res 2020, 13: 729-740. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: We assessed ASD and typically developing individuals for their ability to identify emotional expressions from faces in pictures moving behind a narrow vertical and horizontal slit. ASD patients demonstrated impaired recognition of facial emotional expression only in horizontal slit-viewing. Voxel-based analysis revealed significant negative correlations between behavioral deficits and NODDI index values in clusters including the corpus callosum. Our results indicated deficits in perceptual integration of facial expression across hemispheres in ASD patients potentially resulting from microstructural disturbances.

The Self-Construal Scale: A Potential Tool for Predicting Subjective Well-Being of Individuals With Autism Spectrum Disorder

Despite accumulating evidence that culture shapes the symptoms of autism spectrum disorder (ASD), no studies have yet applied the Self-Construal Scale to individuals with ASD. We compared the self-construals (measured using the Self-Construal Scale) of 31 high-functioning Japanese individuals with ASD with those of 60 typically developing (TD) individuals. We also examined how the self-construals of individuals with ASD related to their intelligence quotient, adverse childhood experiences, attention deficit hyperactivity disorder, ASD symptoms during adulthood and preschool years, and subjective well-being. Individuals with ASD were more likely to display independent self-construals than were TD individuals; unexpectedly, however, a substantial proportion of individuals with ASD (43.8%) displayed relatively interdependent self-construals. Among individuals with ASD, self-construals were significantly associated with ASD symptoms during preschool years, and with satisfaction of the need for autonomy and frustration of the need for relatedness. Evaluating self-construals can help predict the subjective well-being of high-functioning individuals with ASD. Moreover, the Self-Construal Scale may be useful for understanding the heterogeneous phenotypes of ASD, based on its association with autistic symptoms during preschool years, suggesting that the scale is a potential tool to develop efficient interventions for high-functioning individuals with ASD. Autism Res 2020, 13: 947-958. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Autism Spectrum Disorders (ASD) are a group of disorders presenting a variety of symptoms and biological origins that can complicate choosing an intervention best suited for improving well-being. Results indicate that a self-construal scale could help understand individuals with high-functioning ASD by independent and interdependent self-construals that are associated with ASD symptoms during preschool years and adult subjective well-being. Our findings suggest that this scale can help understand ASD and select appropriate interventions.

Assessment of patients with intellectual disability using the International Classification of Functioning, Disability and Health to evaluate dental treatment tolerability

BACKGROUND

Patients with serious intellectual disability (ID) are occasionally unable to tolerate dental treatment when intravenous sedation or general anaesthesia (IVS/GA) is involved. In order to make a decision regarding the application of IVS/GA, the International Classification of Functioning, Disability and Health (ICF) is useful. Therefore, in this study, a set of codes involved in dental problems were chosen from the ICF, and patients with ID who could tolerate dental treatments were compared with those who could not.

METHODS

From preliminary interviews of six patients with ID, 16 codes were chosen, and an objective five-rank scale was then constructed for use with all chosen codes. Forty-nine ID patients who visited the Okayama University Hospital for dental treatment between January and April 2003 were evaluated. Facility workers were interviewed according to the code set chosen. The participants were then divided into two subgroups depending on their tolerability of dental treatment. The results of these groups for all 16 codes were then compared.

RESULTS

Of the 49 patients interviewed, 23 were able to tolerate the dental treatment. In the 'Activities & Participation' section of the ICF, the tolerable group showed lower disability levels with regard to d110 Watching, d540 Dressing and d550 Eating. In other sections, there were no significant differences between the groups. The code set chosen in this study and the five-rank scales in each code were useful as they enabled easy interviewing.

CONCLUSIONS

The ICF was raised as a possibility for considering the application of IVS/GA for dental treatment on patients with ID. For clinical use of the ICF, it is recommended that significant codes should be selected and that the five-rank scale is used so that more objective results are obtained from interviews.

[Evaluation of sternal deformity after pediatric minimally invasive cardiac surgery]

Sternal shape is one of the most important esthetic factors of the chest appearance after pediatric minimally invasive cardiac surgery (pMICS) as well as length of skin wound. We evaluated the grade of postoperative sternal deformity in 20 patients who underwent total repair of pediatric congenital heart disease [atrial septal defect (ASD): 17, ventricular septal defect (VSD): 2, partial anomalous pulmonary venous connection (PAPVC): 1] with minimal skin incision and lower partial median sternotomy. The sternum was closed with stainless wire in 3 patients, with absorbable polydioxanone (PDS) cord in 5 patients, with combined use of reabsorbable radiolucent poly (L-lactate) acid sternal pin and absorbable PDS cord in 12 patients. The evaluation of postoperative sternal deformity was made according to the vertebral index (VI) and frontosagittal index (FSI) in 3 groups with each sternal closure method. VI and FSI of the 3 groups showed no significant difference. Sternal deformity in the group with sternal closure with PDS cord group was more severe than that in other 2 groups. The combined use of sternal pin with PDS cord offered the most sufficient fixative strength for sternal closure.

[An effective case of nitric oxide inhalation therapy in pulmonary hypertensive crisis in cardiopulmonary bypass following palliative operation for ventricular septal defect with pulmonary hypertension]

A 4-month-old female with ventricular septal defect (VSD) and severe pulmonary hypertension (PH) underwent a patch closure for VSD. She could not be weaned from cardiopulmonary bypass (CPB) after the intracardiac repair due to PH crisis. Nitric oxide inhalation therapy during partial CPB enabled her to be weaned from CPB. This therapy could be gradually taped off and quit 7 days after the operation. Nitric oxide inhaled therapy is considered to be an excellent treatment for PH crisis during CPB in congenital cardiac surgery. The causes of PH crisis were also discussed in reference to the date of endothelin-1 (ET-1) measured during the operation.

Imidazole-induced cell death, associated with intracellular acidification, caspase-3 activation, DFF-45 cleavage, but not oligonucleosomal DNA fragmentation

Intracellular acidification is known to be involved in the initiation phase of apoptosis. However, the necessity of intracellular acidic conditions in the execution phase of apoptosis remains unknown. In this study, we found that in HL-60 cells imidazole induces cell death, associated with intracellular acidification, caspase-3 activation and DFF-45 cleavage, but not oligonucleosomal DNA fragmentation. A caspase inhibitor prevented cell death but not intracellular acidification. When pHi was neutralized by changing from imidazole-containing medium to fresh medium, oligonucleosomal DNA fragmentation and increased caspase-3 activity was observed in the imidazole-treated HL-60 cells. Furthermore, the DNA fragmentation induced by intracellular neutralization was inhibited by caspase inhibitor treatment. These results indicate that imidazole induces caspase-dependent cell death, and suggest that maintaining pHi in the neutral range is essential for the induction of oligonucleosomal DNA fragmentation in the execution phase of apoptosis.

Three TNFalpha single nucleotide polymorphisms in the Japanese population

BACKGROUND

Tumour necrosis factor-alpha (TNFalpha) is an essential regulator of immune responses and is implicated to relate to several types of disease susceptibilities. Population information on polymorphisms is essential for the study of genetic diseases.

AIM

To obtain accurate information about single nucleotide polymorphisms (SNPs) in the TNFalpha gene in the Japanese population.

SUBJECTS AND METHODS

The entire TNFalpha gene was screened for SNPs by directly sequencing 48 chromosomes derived from 24 unrelated Japanese individuals. Allele frequencies of each polymorphism were determined and compared with those previously reported in other populations.

RESULTS

Three SNPs, -308G/A at nt -308, IVS1 + 125G/A at nt 492 and IVS3 + 104G/A at nt 1359 were observed, of which one (IVS3 + 104G/A at nt 1359) was novel. In addition, allele frequencies of -308G/A were remarkably different from those presented in the NCBI dbSNP, indicating a significant ethnic difference.

CONCLUSIONS

The polymorphisms and allele frequencies obtained in this study will be useful for genetic studies of common diseases such as osteoporosis and rheumatoid arthritis in the Japanese population.

Antitumor activity of a phenoxazine compound, 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one against human B cell and T cell lymphoblastoid cell lines: induction of mixed types of cell death, apoptosis, and necrosis

PURPOSE

We studied the antitumor activity of 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx), which was synthesized by the reactions of 2-amino-5-methylphenol with bovine hemoglobin, on human B cell lymphoblastoid cell lines, P3HR-1 and Raji derived from African Burkitt's lymphoma, and the human T cell lymphoblastoid cell line Molt-4. We also studied whether Phx might cause apoptosis and necrosis in these cells.

METHODS

We evaluated cell viability and apoptosis and necrosis of the cells in the presence of Phx, by using agarose gel electrophoresis, flow cytometry, and fluorescence microscopy.

RESULTS

Phx suppressed the viability of P3HR-1, Raji, and Molt-4 cells, though the suppression patterns were different, i.e., Phx suppressed the viability of P3HR-1, Raji, and Molt-4 cells at higher concentrations, while the drug enhanced the viability of Raji cells, but not those of P3HR-1 and Molt-4 cells at lower concentrations. To investigate which type of cell death - apoptosis or necrosis - is induced by Phx, induction of DNA ladder, phosphatidylserine externalization, and propidium iodide-permeable cells were examined in Phx-treated cells. Although Phx did not induce DNA ladder formation, it induced the phosphatidylserine externalization and propidium iodide-permeable cells, suggesting that Phx caused a mixed type of cell death, both apoptosis and necrosis. The population of early stage apoptotic cells was dominant in Raji cells, and that of the late stage apoptotic/necrotic cells was dominant in Molt-4 cells after 72-h treatment with Phx. The population of the early stage apoptotic cells and the late stage apoptotic/necrotic cells was almost equal in P3HR-1 cells in the presence of Phx, though the population of both types of cells increased with time. The nuclear morphological analysis of Phx-treated Raji, P3HR-1, and Molt-4 cells also showed that Phx induces apoptosis.

CONCLUSIONS

The present results suggest that Phx shows antitumor activity against human B cell-derived and T cell-derived lymphoblastoid cell lines, in vitro, causing apoptosis and necrosis.

Thirteen single-nucleotide polymorphisms in the human osteopontin gene identified by sequencing of the entire gene in Japanese individuals

Osteopontin (OPN) is one of the major noncollagenous bone matrix proteins produced by osteoblasts and osteoclasts. We systematically surveyed the entire structure of the OPN gene for single-nucleotide polymorphisms (SNPs) by directly sequencing 48 alleles derived from 24 unrelated Japanese individuals. We identified 13 SNPs in the OPN gene. Ten polymorphisms were identified in introns 1, 3, and 5; 2 in the coding region of exons 6 and 7; and 1 in the 3' untranslated region of exon 7. Allele frequencies for some of the polymorphisms were significantly different from those reported in the United States National Center for Biotechnology Information (NCBI) dbSNP database. These polymorphisms will be useful in genetic studies to evaluate the role of OPN proteins in bone metabolism.

Linkage disequilibrium and haplotype analysis among four novel single-nucleotide polymorphisms in the human leukemia inhibitory factor (LIF) gene

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine implicated in various pathological conditions, such as rheumatoid arthritis and osteoporosis. Despite the possible importance of LIF as a therapeutic target, little is known about the bioregulation of the human LIF gene. We here sequenced the entire structure of the LIF gene of 48 alleles in the Japanese population. These experiments identified four single-nucleotide polymorphisms (SNPs) and determined their allelic frequencies from a 48-allele sequence in the Japanese population. All four SNPs found in the LIFgene were located within exon 3, that is, a C/T at nucleotide (nt) position 3951, a C/G at nt position 4376, an A/C at nt position 4442, and a G/A at nt position 5961 (nucleotide numbering starts from the ATG start codon). Based on the genotypic data, we constructed four major haplotypes in the tested population. Two-way comparisons of SNPs revealed complete linkage disequilibrium between SNPs at positions 3951, 4376, and 4442. These results may prove to be useful as genetic markers for population-based disease-association studies in osteoporosis.

Linkage disequilibrium and haplotype analysis among ten single-nucleotide polymorphisms of interleukin 11 identified by sequencing of the gene

Interleukin (IL11) is a member of the interleukin 6 (IL6)-related cytokine subfamily, which stimulates T cell-dependent development of immunoglobulin-producing B cells. IL11 is also an important paracrine regulator of bone metabolism that induces formation of osteoclasts. In the work reported here, we sequenced the entire IL11 structural gene of 48 alleles in a Japanese test population. These experiments identified ten single-nucleotide polymorphisms (SNPs) and determined their allelic frequencies. One polymorphism was identified upstream of exon 1, one in exon 3, four in intron 4 and four in the 3' untranslated region (3'UTR) of exon 5. Based on the genotype data, we constructed six haplotypes in the tested population. Two-way comparisons of SNPs revealed two combinations in complete linkage disequilibrium, one with SNPs at nucleotide positions 2753, 3644, 5154, and 5568, and another with SNPs at positions 3686, 5141, and 5734. These results will be useful in disease-association studies where a contribution of the human IL11 gene has been suspected, especially in disorders affecting immune response and bone metabolism.

[Analysis of correlation between physical training and autonomic function by using multivariate analysis: establishing an indicator of health]

The purpose of this study is to assess the effects of physical training on autonomic nervous function. Twenty-two healthy subjects(12 males and 10 females) participated in this study. We inquired contents of the exercise for each subject. Continuous ECG was recorded during 320 seconds at supine resting. Respiratory rhythm was fixed at 0.25 Hz(15 time/min). On the basis of spectral analysis of heart rate variability, the autonomic nervous function was assessed by low frequency power(LF: 0.06-0.13 Hz) and high frequency power(HF: 0.16-0.50 Hz). The predominance of sympathetic nervous activity were indicated by the LF/HF and LF-HF. Relationship between physical training and autonomic function was analyzed by using multivariate analysis(partial correlation analysis). As the results, LF power and LF-HF negatively correlated with training time per day, energy expenditure per day, energy expenditure per week, and total energy expenditure, respectively(p < 0.05). HF power positively correlated with energy expenditure per day, energy expenditure per week, and total energy expenditure, respectively(p < 0.05). These results indicate not training time but energy expenditure alters the autonomic nervous function. This index may be useful for evaluating training effect on the promotion of health.

Successful surgical management of a tracheopulmonary artery fistula caused by an intratracheal expandable metal stent

We describe a boy who underwent slide tracheoplasty and relocation of the left pulmonary artery at 3 months of age to treat pulmonary artery sling with congenital tracheal stenosis. Persisting tracheal stenosis required that he have a Palmaz stent inserted on postoperative day 77. He developed massive hemoptysis after the fourth attempt to expand the stent balloon and immediate computed tomography showed a tracheopulmonary artery fistula. Using cardiopulmonary bypass, we conducted emergency surgery to successfully manage the fistula. He currently depends on mechanical ventilation.

Functional evaluation with intravoxel incoherent motion echo-planar MRI in irradiated salivary glands: a correlative study with salivary gland scintigraphy

The purpose of this study was to determine the relationship between the apparent diffusion coefficient (ADC) measured on intravoxel incoherent motion (IVIM) echo-planar magnetic resonance imaging (MRI) and salivary gland function. Twenty-one patients with head and neck malignancies underwent MRI and salivary gland scintigraphy before and after radiotherapy. Based on the scintigraphic results, each major salivary gland was classified into two groups (dysfunctional and functional) and ADCs measured on IVIM MRI were compared between the two groups. Furthermore, the relationship of ADC to scintigraphic parameters, maximum accumulation (MA), and the uptake ratio (UR), were analyzed. ADCs of the dysfunctional group decreased significantly after radiotherapy (P <.01), whereas those of the functional group showed no significant change. Furthermore, positive correlations were found between the ADC ratio and both MA (P <.005) and UR (P <.001). ADC measurement on IVIM echo-planar MRI is a potentially useful means of evaluating salivary gland function.

Phosphatidylserine induces apoptosis in adherent cells

Phosphatidylserine (PS) is exposed on the outer leaflet of the plasma membrane in apoptotic cell death. However, the roles of PS in apoptotic signaling are still unclear. In this study, we found that exogenous PS, but not other phospholipids, induced cell death in adherent cells, but not in suspension culture. The cell death exhibited typical features of apoptosis such as cell shrinkage, nuclear fragmentation and abnormal chromatin condensation. When PS was added to CHO-K1 cells in monolayer culture, they began to show changes in cell shape and actin cytoskeleton and protein kinase C (PKC) activity, followed by cell detachment, caspase activation, cleavage of focal adhesion kinase (FAK) and finally loss of viability. These results suggested that PS causes apoptosis through actin disorganization, cell detachment and cleavage of FAK.

Direct closure of ostium primum defect in the repair of atrioventricular septal defect

BACKGROUND

Patch closure is generally performed for atrial septation of an atrioventricular septal defect. We recently developed a new surgical technique for repairing atrioventricular septal defects that avoids the use of any patch material for closing the atrial septal defect. We report our experience with this procedure.

METHODS

Seven patients (complete type: 5, partial type: 2) underwent this new operation. The diameters of the atrial septal defects were measured by transesophageal echocardiography. The preoperative electrocardiograms were compared with those taken after the operations.

RESULTS

Diameters of the atrial defects ranged from 3 to 10 mm. Electrocardiograms before and after the operations did not change. No significant atrioventricular valve regurgitation and no residual shunts were detected by postoperative echocardiography.

CONCLUSIONS

This method simplifies the repair of atrioventricular septal defects. In the short-term results, no arrhythmia and no valve regurgitation was seen.

Mitotic specific phosphorylation of serine-1212 in human DNA topoisomerase IIalpha

It is known that topoisomerase IIalpha is phosphorylated by several kinases. To elucidate the role of phosphorylation of topoisomerase IIalpha in the cell cycle, we have examined the cell cycle behavior of phosphorylated topoisomerase IIalpha in HeLa cells using antibodies against several phospho-oligopeptides of this enzyme. Here we demonstrate that serine1212 in topoisomerase IIalpha is phosphorylated only in the mitotic phase. Using an antibody against an oligopeptide containing phosphoserine-1212 in topoisomerase IIalpha (PS1212), subcellular localization of topoisomerase IIalpha phosphorylated at serine1212 was examined by indirect immunofluorescence staining, and compared with that of overall topoisomerase IIalpha. Serine1212-phosphorylated topoisomerase IIalpha was localized specifically on mitotic chromosomes, but not on interphase chromosomes; this result contrasts with overall topoisomerase IIalpha which was observed on chomosomes in both interphase and mitosis. Serine1212-phosphorylated topoisomerase lIalpha first appeared on chromosome arms in prophase, became concentrated on the centromeres in metaphase, and disappeared in early telophase. In addition, ICRF-193, a catalytic inhibitor of topoisomerase II, prevented accumulation of serine1212-phosphorylated topoisomerase IIalpha at the centromeres. These results indicate that serine1212 of topoisomerase IIalpha is phosphorylated specifically during mitosis, and suggest that the serine1212-phosphorylated topoisomerase IIalpha acts on resolving topological constraint progressively from the chromosome arm to the centromere during metaphase chromosome condensation.

Differentiating between progressive supranuclear palsy and corticobasal degeneration by brain perfusion SPET

The purpose of this study was to evaluate the usefulness of brain perfusion single photon emission computed tomography (SPET) to differentiate between progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Twelve patients with PSP and 12 with CBD were examined by brain perfusion SPET using 99Tc(m)-ethyl cysteinate dimer (99Tc(m)-ECD). The regions of interest (ROIs) were five cortical regions, the basal ganglia, the thalamus, the cerebellar cortex and the brain stem. The mean regional cerebral blood flow (CBF) and the mean right/left asymmetry index in each ROI were calculated. The asymmetry index of the regional CBF was significantly higher in CBD patients compared with PSP patients in all of the cortical regions and in the basal ganglia. The greatest differences in asymmetry were in the parietal cortex (P<0.001), high frontal cortex (P<0.001), frontal cortex (P<0.005), temporal cortex (P<0.01) and basal ganglia (P<0.01). Significant asymmetry was also detected in the occipital cortex (P < 0.05). No significant difference in asymmetry was found in the thalamus or the cerebellum. There were no significant differences between the two groups in any of the regional CBF values. In conclusion, brain perfusion SPET with 99Tc(m)-ECD is useful in detecting the significantly higher perfusion asymmetry in CBD patients compared with PSP patients in all cortical regions and in the basal ganglia. SPET may be a useful tool for differentiating between PSP and CBD.

An improved method for the rapid preparation of 2-amino-4,4a-dihydro-4a,7-dimethyl-3H-phenoxazine-3-one, a novel antitumor agent

A simple and rapid preparation method for a novel antitumor agent, 2-amino-4,4a-dihydro-4a,7-dimethyl-3H-phenoxazine-3-one (Phx) was described. The procedure included (1) the reaction of bovine hemolysates with 2-amino-5-methylphenol, (2) one-shot denaturation of hemoglobin and proteins by methanol, and removal of the denatured hemoglobin and proteins, (3) concentration of the reaction products, and (4) purification by a Sephadex column. These procedures yielded Phx in 34% yield.

Atraumatic hemarthrosis caused by a large mediopatellar plica

Hemarthrosis of the knee has various etiologies and is classified into atraumatic or post-traumatic. Among atraumatic factors, hemarthrosis due to synovial plica is extremely rare. We report a case of atraumatic hemarthrosis caused by the mediopatellar plica. A 21-year-old male truck driver was referred to our hospital, because of swelling and pain of the right knee without history of trauma. Bloody synovial fluid was aspirated by arthrocentesis. However, his symptoms recurred and persisted. The range of motion was normal, but the patient complained of anteromedial knee pain during maximum flexion. Routine biochemical analyses were within normal limits. Plain radiographs were normal. Magnetic resonance imaging (MRI) of the knee showed the hypertrophic mediopatellar plica and an irregular signal of the infrapatellar fat pad. Arthroscopy revealed a voluminous mediopatellar plica trapped between the patella and the medial femoral condyle. It attached to the center of the infrapatellar fat pad, the so-called tongue. When the tourniquet was released, fresh bleeding was observed from the region between the mediopatellar plica and the tongue. Because that region was considered to be the cause of the hemarthrosis, the mediopatellar plica and the tongue were excised. A histologic examination of the tongue showed evidence of bleeding with nonspecific synovitis. After the procedure, the patient was asymptomatic and there were no clinical signs of recurrence.

Antitumor effects of a novel phenoxazine derivative on human leukemia cell lines in vitro and in vivo

2-Amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx) was synthesized by reacting 2-amino-5-methylphenol with bovine hemolysates. Because Phx is a phenoxazine derivative like actinomycin D, we examined its effects on the proliferation of the human leukemia cell lines K562, HL-60, and HAL-01. Phx inhibited proliferation and induced apoptosis in all of the leukemia cell lines we tested, in a dose-dependent manner. We further investigated the antitumor effect of this compound on HAL-01-bearing nude mice. Treatment with Phx markedly reduced the tumor growth rate in the experimental group, as compared with the control group. Moreover, Phx was found to have few adverse effects on weight loss and WBC count. In addition, we examined the effects of Phx on human normal hematopoietic progenitor cells by a clonogenic assay, and we observed less suppression of normal progenitor cells than of leukemic progenitors. These results suggest that Phx may be used to treat patients affected by different types of leukemia.

Tc-99m DTPA renography in patients with collagen disease

PURPOSE

This study evaluated the use of Tc-99m DTPA renography in patients with collagen disease.

MATERIALS AND METHODS

Tc-99m DTPA renal scintigraphy was performed in 28 patients with clinically diagnosed collagen disease. Twenty-two other patients who underwent renal scintigraphy and were subsequently shown to have no kidney abnormalities served as the control group.

RESULTS

One quarter of the patients with collagen disease had abnormal findings of renography, despite the absence of abnormal laboratory data. Renograms were 100% sensitive for the detection of renal disease in patients with collagen disease, and their specificity was 53% when serum blood urea nitrogen, serum creatinine concentration, and proteinuria were the only measures of renal impairment considered. The glomerular filtration rate was not significantly different between the groups, but the bilateral time to peak was significantly greater in the patients with collagen disease. Hydronephrosis was present in 7% of patients with collagen disease.

CONCLUSION

Renography is useful for detecting early changes of renal involvement when the clinical state of collagen disease is evaluated.

Direct measurement of low-density-lipoprotein cholesterol is more effective than total cholesterol for the purpose of lipoprotein screening

BACKGROUND

We have developed a new method for chemically measuring blood low-density-lipoprotein (LDL) cholesterol. In the present study, we simulated guidelines of the National Cholesterol Education Program (NCEP) using our LDL cholesterol measurements.

METHODS

Blood samples were collected from 1,069 individuals (519 males, 550 females) who were referred to our laboratory at Niigata University Hospital for lipoprotein analysis. LDL cholesterol levels were determined according to our assay protocol, which has been published previously. Subjects were categorized by NCEP guidelines and identified "false positives" and "false negatives" on the basis of LDL cholesterol levels measured by our method.

RESULTS

The sensitivity of the NCEP guidelines is 87.5% and the specificity is 87.1%, provided we assume that every individual has fewer than two risk factors for coronary heart disease. If we assume that every individual has two or more risk factors, the sensitivity and specificity of the guidelines are 99 and 56.8%, respectively.

CONCLUSION

This study presents an opportunity to reevaluate guidelines for routine lipoprotein screening. The chance that individuals with higher LDL cholesterol and lower high-density-lipoprotein cholesterol levels in serum would be missed at initial classification should be zero. The chance that individuals with desirable lipid levels would undergo further lipoprotein analysis should be decreased. Since the new method can be implemented cost-effectively in routine lipoprotein screening, direct measurement of LDL cholesterol could replace total cholesterol.