Telomeric length and telomerase activity vary with age in peripheral blood cells obtained from normal individuals

The telomerase activity and length of telomeres of peripheral blood mononuclear cells obtained from 124 healthy individuals aged 4-95 years was measured. Telomerase activity level was semiquantitatively assessed by a fluorescent-telomeric repeat amplification protocol (fluorescent-TRAP) using an internal telomerase assay standard, fluorescent primers and an automated laser fluorescent DNA sequencer. Telomeric length, measured by assay of terminal restriction fragments (TRFs), was determined in HinfI-digested DNA by Southern blot analysis using a (TTAGGG)4 probe. TRF length was determined in 80 individuals and age-related progressive reduction of size was observed. TRF length in peripheral blood mononuclear cells obtained from normal individuals (aged 4-39 years) decreased by approximately 84 bp per year, while in individuals aged > or = 40 years it decreased by 41 bp per year. In contrast, telomerase activity showed an apparent biphasic pattern with aging. Individuals aged 4-39 years showed a progressive decrease in telomerase activity, whereas 65% of those aged > or = 40 years showed relatively stable but very low telomerase activity, and the remaining individuals aged > or = 40 years had no detectable telomerase activity. These data obtained from normal individuals might in the future be of value to help risk stratify and manage the care of patients with leukemia.

Detection and sequencing of measles virus from peripheral mononuclear cells from patients with inflammatory bowel disease and autism

It has been reported that measles virus may be present in the intestine of patients with Crohn's disease. Additionally, a new syndrome has been reported in children with autism who exhibited developmental regression and gastrointestinal symptoms (autistic enterocolitis), in some cases soon after MMR vaccine. It is not known whether the virus, if confirmed to be present in these patients, derives from either wild strains or vaccine strains. In order to characterize the strains that may be present, we have carried out the detection of measles genomic RNA in peripheral mononuclear cells (PBMC) in eight patients with Crohn's disease, three patients with ulcerative colitis, and nine children with autistic enterocolitis. As controls, we examined healthy children and patients with SSPE, SLE, HIV-1 (a total of eight cases). RNA was purified from PBMC by Ficoll-paque, followed by reverse transcription using AMV; cDNAs were subjected to nested PCR for detection of specific regions of the hemagglutinin (H) and fusion (F) gene regions. Positive samples were sequenced directly, in nucleotides 8393-8676 (H region) or 5325-5465 (from noncoding F to coding F region). One of eight patients with Crohn disease, one of three patients with ulcerative colitis, and three of nine children with autism, were positive. Controls were all negative. The sequences obtained from the patients with Crohn's disease shared the characteristics with wild-strain virus. The sequences obtained from the patients with ulcerative colitis and children with autism were consistent with being vaccine strains. The results were concordant with the exposure history of the patients. Persistence of measles virus was confirmed in PBMC in some patients with chronic intestinal inflammation.

Serum and cerebrospinal fluid nitrite/nitrate levels in patients with rotavirus gastroenteritis induced convulsion

Nitric oxide (NO) is a highly reactive free radical that is involved in a variety of different biological process. In recent reports, the putative role of NO in the neuropathogenesis of brain inflammation has been demonstrated. And then the relation between neuronal NO and convulsive seizures induced by virus has been suggested. However, there are few reports about NO in vivo under viral neurological infections. In order to evaluate the relation between NO production and neurological disorders induced by viral infection, sixty-six cases including 11 patients with rotavirus gastroenteritis admitted for convulsions were examined in this study. NO metabolites (NOx) levels in both serum and cerebrospinal fluid obtained from rotavirus gastroenteritis patients with convulsion were much higher than in those of patients with purulent meningitis, encephalitis, febrile convulsion or in the control group. There was a relative correlation between IL-6 and NOx in some cases. These results indicated that NO may have a pathophysiological role in convulsions associated by rotavirus infection either through indirect or direct effects of NO. Consequently, NOx inhibitors might be helpful for the treatment of rotavirus encephalopathy.

Beta-catenin interacts with the FUS proto-oncogene product and regulates pre-mRNA splicing

BACKGROUND & AIMS

beta-Catenin is a downstream effector of the Wnt signaling pathway and is believed to exert its oncogenic function by activating T-cell factor (TCF)/lymphoid enhancer factor (LEF) family transcriptional factors. However, it is still uncertain whether the diverse effects of beta-catenin are caused solely by aberrant gene transactivation. In this study, we used a proteomics approach to obtain further insight into the functional properties of nuclear beta-catenin.

METHODS

The protein assembly of a native beta-catenin-containing complex in nuclear extracts from a colorectal cancer cell line, DLD-1, was identified using immunoprecipitation and mass spectrometry.

RESULTS

beta-Catenin physically interacted with fusion (FUS)/translocated in liposarcoma (TLS) and various RNA-binding proteins. The expression of FUS/TLS was closely associated with the accumulation of beta-catenin and with the undifferentiated status of intestinal epithelial cells. The transient transfection of FUS suppressed beta-catenin-evoked gene transactivation of TCF/LEF, and beta-catenin transfection affected the splicing pattern of the E1A minigene and induced a novel splicing variant of estrogen receptor (ER)-beta exerting a dominant-negative activity.

CONCLUSIONS

Human cancer expresses a large variety of alternatively spliced messenger RNA (mRNA), but the precise molecular mechanisms responsible for cancer-related alternative splicing are largely unknown. In this study, we demonstrated the interaction of beta-catenin with FUS/TLS and other RNA-binding proteins involved in the regulation of pre-mRNA splicing. Certain mRNA splicing abbreviations seen in human cancers may be induced by the activation of the Wnt signaling pathway.

Long-term correction of hyperphenylalaninemia by AAV-mediated gene transfer leads to behavioral recovery in phenylketonuria mice

Classical phenylketonuria (PKU) is a metabolic disorder caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH). If untreated, accumulation of phenylalanine will damage the developing brain of affected individuals, leading to severe mental retardation. Here, we show that a liver-directed PAH gene transfer brought about long-term correction of hyperphenylalaninemia and behavioral improvement in a mouse model of PKU. A recombinant adeno-associated virus (AAV) vector carrying the murine PAH cDNA was constructed and administered to PAH-deficient mice (strain PAH(enu2)) via the portal vein. Within 2 weeks of treatment, the hyperphenylalaninemic phenotype improved and completely normalized in the animals treated with higher vector doses. The therapeutic effect persisted for 40 weeks in male mice, while serum phenylalanine concentrations in female animals gradually returned to pretreatment levels. Notably, this long-term correction of hyperphenylalaninemia was associated with a reversal of hypoactivity observed in PAH(enu2) mice. While locomotory activity over 24 h and exploratory behavior were significantly decreased in untreated PAH(enu2) mice compared with the age-matched controls, these indices were completely normalized in 12-month-old male PKU mice with lowered serum phenylalanine. These results demonstrate that AAV-mediated liver transduction ameliorated the PKU phenotype, including central nervous system dysfunctions.

Umbilical cord milking stabilizes cerebral oxygenation and perfusion in infants born before 29 weeks of gestation

OBJECTIVE

To investigate the effects of umbilical cord milking at birth on cerebral perfusion and systemic perfusion in very low birth weight (VLBW) infants.

STUDY DESIGN

Cerebral tissue oxygenation index and cerebral fractional tissue oxygen extraction were monitored in 50 stable VLBW infants (gestational age <29 weeks, birth weight <1250 g), with 26 allocated to the milked group and 24 to the control group. We used near-infrared spectroscopy 3-6, 12, 18, 24, 36, 48, and 72 hours after birth. Left ventricular end-diastolic dimension, left ventricular ejection fraction, left ventricle (LV) Tei index (measurement of left ventricular systolic and diastolic function), left ventricular cardiac output, and superior vena cava flow were measured concurrently using echocardiography.

RESULTS

There were no significant differences in gestational age and birth weight between the 2 groups. Hematocrit, left ventricular end-diastolic dimension, left ventricular cardiac output, and superior vena cava flow were higher in the milked group than in the control group, with improvement in the LV Tei index despite the absence of left ventricular ejection fraction changes within 24 hours after birth. Tissue oxygenation index increased and cerebral fractional tissue oxygen extraction decreased in the milked group within 24 hours after birth.

CONCLUSION

Umbilical cord milking stabilized cerebral oxygenation and perfusion in VLBW infants by improving LV diastolic function by increasing LV preload.

Inducing proliferation of human amniotic epithelial (HAE) cells for cell therapy

Probably because amnion is derived from the fetus and is exposed to the maternal immune system, human amniotic epithelial (HAE) cells do not express the HLA-A, -B, -C, or -DR antigens on their surfaces, suggesting that HAE cells do not induce rejection (immune reaction) after allotransplantation. And the amnion, like the placenta, is useless to the mother and child after birth. Therefore, HAE cells or tissues were expected to be suitable for allotransplantation. Because HAE cells produce large amounts of enzymes, amnion transplantation has been carried out in order to correct inborn errors of metabolism by supplementing lysosomal enzyme deficiencies. However, several problems remain before amnion allotransplantation can be accepted as effective. The HAE cell population is limited, because the maximum number of HAE cells obtainable from one donor is about 2 x 10(8) cells, and HAE cells proliferate poorly in in vitro culture. In this study, we aimed at increasing the HAE cell population in vitro. First, we investigated the effect of several cytokines on HAE cell proliferation and found that hepatocyte growth factor (HGF), epidermal growth factor (EGF), and transforming growth factor-beta stimulated it, whereas IL-6 and LIF inhibited it. Second, we investigated the effects of amniotic fluid on HAE cell proliferation and observed that IL-6 in amniotic fluid inhibits it. Then, to inhibit the dying of cells, we attempted to inhibit apoptosis (one mode of cell death). Treatment with caspase III inhibitor increased the cell viability of HAE cells by 20%.

Noninvasive monitoring of deterioration in skeletal muscle function with forearm cast immobilization and the prevention of deterioration

Background

In this research inactivity was simulated by immobilizing the forearm region in a plaster cast. Changes in skeletal muscle oxidative function were measured using near-infrared spectroscopy (NIRS), and the preventative effect of the training protocol on deterioration of skeletal muscle and the clinical utility of NIRS were examined.

Methods

Fourteen healthy adult men underwent immobilization of the forearm of the non-dominant arm by plaster cast for 21 days. Eight healthy adult subjects were designated as the immobilization group (IMM) and six were designated as the immobilization + training group (IMM+TRN). Grip strength, forearm circumference and dynamic handgrip exercise endurance were measured before and after the 21-day immobilization period. Using NIRS, changes in oxidative function of skeletal muscles were also evaluated. Muscle oxygen consumption recovery was recorded after the completion of 60 seconds of 40% maximum voluntary contraction (MVC) dynamic handgrip exercise 1 repetition per 4 seconds and the recovery time constant (TcVO₂mus) was calculated.

Results

TcVO₂mus for the IMM was 59.7 ± 5.5 seconds (average ± standard error) before immobilization and lengthened significantly to 70.4 ± 5.4 seconds after immobilization (p < 0.05). For the IMM+TRN, TcVO₂mus was 78.3 ± 6.2 seconds before immobilization and training and shortened significantly to 63.1 ± 5.6 seconds after immobilization and training (p < 0.05).

Conclusions

The training program used in this experiment was effective in preventing declines in muscle oxidative function and endurance due to immobilization. The experimental results suggest that non-invasive monitoring of skeletal muscle function by NIRS would be possible in a clinical setting.

Classification of acute encephalopathy in respiratory syncytial virus infection

Infection with respiratory syncytial virus (RSV) is known to be associated with central nervous system symptoms such as convulsions. We investigated cytokines, nitrogen oxide (NO)( x ), and the viral genome in cerebrospinal fluid (CSF) obtained from children with RSV infection-related convulsions or central nervous symptoms and compared the data with type of encephalopathy. Of nine patients enrolled (six boys and three girls; aged 10 days-3 years), one metabolic error, five excitotoxicity, one cytokine storm, and two hypoxia cases were found. The patients presented with unilateral convulsions, generalized convulsions, and convulsions following cardiopulmonary arrest, apnea, and nuchal rigidity. In all patients, a rapid check for RSV of nasal fluid was positive. The RSV genome (subgroup A) was detected in the CSF of five of the nine patients; two patients with hypoxic encephalopathy were negative for the RSV genome. The CSF interleukin (IL)-6 levels were high only in patients with the excitotoxicity and cytokine storm type of encephalopathy. NO( x ) levels were high in all the subject cases. In the excitotoxicity type, NO( x ) levels were significantly higher than those in the control and other groups. NO( x ) level may become an important parameter for the diagnosis and classification of acute encephalopathy in RSV. Strategies to treat each type of encephalopathy, targeting cytokines and free radicals, should be established.

Methylation status of the p15 and p16 genes in paediatric myelodysplastic syndrome and juvenile myelomonocytic leukaemia

Aberrant DNA methylation is frequently observed in adults with myelodysplastic syndrome (MDS), and is recognized as a critical event in the disease's pathogenesis and progression. This is the first report to investigate the methylation status of p15 and p16, cell cycle regulatory genes, in children with MDS (n = 9) and juvenile myelomonocytic leukaemia (JMML; n = 18) by using a methylation-specific polymerase chain reaction. The frequency of p15 hypermethylation in paediatric MDS was 78% (7/9), which was comparable to that in adult MDS. In contrast, p15 hypermethylation in JMML was a rare event (17%; 3/18). In JMML, clinical and laboratory characteristics including PTPN11 mutations and aberrant colony formation were not different between the three patients with hypermethylated p15 and the others. Aberrant methylation of p16 was not detected in children with either MDS or JMML. Since p15 and p16 genes were unmethylated in two children with JMML, in whom the disease had progressed with an increased number of blasts, a condition referred to as blastic crisis, we infer that the aberrant methylation of these genes is not responsible for the progression of JMML. The results suggest that demethylating agents may be effective in most children with MDS and a few patients with JMML.

Combined treatment of steroids and cyclosporine in Kimura disease

Kimura disease is a rare but distinctive chronic eosinophilic inflammatory disorder that is characterized by tumor-like lesions in the soft tissue and lymph nodes of the head and neck or parotid gland. Recently, many immunopathogenetic features of underlying T lymphocytes and related cytokines have been noted in Kimura disease. However, few previous studies have investigated the serial levels of cytokines in children. In this report we describe an 11-year-old Japanese boy with relapsing Kimura disease. Before the diagnosis of Kimura disease, the patient had a swelling on his left neck. Steroids were effective, but the tumor relapsed within a few months as the steroids were tapered. He was treated with steroids and cyclosporine. This treatment was done by measuring serial levels of serum soluble interleukin-2 receptor, interleukin-4, interleukin-5, and eosinophil cationic protein. These results suggest the activation of T-helper cells and T-helper 2 cytokines, that after activated B cells and eosinophilic infiltration play an important role in Kimura disease, and that cyclosporine suppresses the activity of this disease.

Diagnostic and predictive value of CSF d-ROM level in influenza virus-associated encephalopathy

The aim of this study was to assess the validity of serum and CSF oxidative status of patients with IE in their initial stage through the d-ROM (Diacron-Reactive Oxygen Metabolites, Italy) test, compared to those with other neurological diseases. The study was conducted on the following four groups: (1) influenza virus-associated encephalopathy (IE, n = 8), including four patients showing neurological sequelae or mortal; (2) influenza virus-associated febrile seizures (IFS, n = 11); (3) febrile convulsion (FC, n = 10): (4) enterovirus-associated encephalopathy (EE, n = 4), including one patient with neurological sequelae. The CSF d-ROM levels in the IE group were significantly higher than those in the IFS and the FC groups but not in the EE group. In addition, general laboratory findings such as leukocytes, platelets, C-reactive protein, aspartate aminotransferase, creatinine, creatinine kinase and LDH, including interleukin-6 (IL-6), were analyzed in each group. The CSF d-ROM levels in the IE group were significantly higher than those in the IFS and FC groups but not in the EE group. As for the serum d-ROM levels and general laboratory findings, with the exception of CSF IL-6 levels in IE, no significant differences were detected compared with the other groups. In patients with IE, the CSF d-ROM levels could be a valid predictive biomarker of the severity, and oxidative stress may be related to the pathogenesis of IE.

Efficacy of plasma exchange and methylprednisolone pulse therapy on influenza-associated encephalopathy

Patients with a new type of influenza-associated encephalopathy with high mortality are increasing in Japan and the United States. We present three patients treated with methyprednisolone pulse treatment and plasma exchange to remove cytokines, and all three patients recovered without severe sequela. IL-6 decreased dramatically after the start of the plasma exchange and methyprednisolone. Therefore when influenza-associated encephalopathy is actually diagnosed, steroid pulse therapy should be started at an early stage, and when signs of DIC and/or MOF appear, plasma exchange is recommended to remove the cytokines and NOx.

Production of chemokines in respiratory syncytial virus infection with central nervous system manifestations

Respiratory syncytial virus (RSV) infection in children can be associated with acute encephalopathy. However, the roles of cytokines in the cerebrospinal fluid (CSF) of such patients remain unevaluated. In this study, a profile of 17 cytokines was determined for eight RSV-infected children with neurological complications. In one patient with high levels of 13 cytokines, a cytokine storm was considered to have occurred. Interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, and macrophage inflammatory protein (MIP)-1β levels were also high in other patients. These data suggest that chemokines in CSF play roles in neurological complications in RSV-infected children.

Non-convulsive status epilepticus

The clinical, electrographic and reported neuropsychological features of 50 children with non-convulsive status epilepticus (NCSE) were reviewed and the children's progress followed for one to five years. NCSE occurred in a variety of epilepsies, especially the Lennox-Gastaut syndrome. Clinical manifestations ranged from obvious mental deterioration to subtle changes. The condition had often been overlooked or misinterpreted and many children had experienced repeated episodes over long periods. Following diagnosis, immediate treatment was often not attempted or was not successful. Further episodes of NCSE occurred in the majority of children during the follow up period. Failure to recognise NCSE and to treat episodes promptly, and the high rate of recurrence, is of particular concern in view of fears that repeated exposure to this condition might be brain damaging. At least 28 children in the present series showed evidence of intellectual or educational deterioration over the period during which NCSE had occurred, although the exact cause was difficult to determine.

Expressions of brain-derived neurotrophic factor (BDNF) in cerebrospinal fluid and plasma of children with meningitis and encephalitis/encephalopathy

Many reports in the field of childhood brain disorders have documented that brain-derived neurotrophic factor (BDNF) affects central nervous system (CNS) functions. In this clinical study, BDNF levels were evaluated in association with pediatric CNS infections. BDNF levels in the serum and cerebrospinal fluid (CSF) of 42 patients admitted during 5-year period, due to CNS infections, were measured by enzyme-linked immunosorbent assays (ELISAs). Control samples were collected from 108 patients with non-CNS infections (urinary tract infection, acute upper respiratory infection, acute gastroenteritis, etc.). Mean values of BDNF levels, at various ages, were determined and compared. BDNF levels were below the sensitivity of the ELISA in most CSF samples from the control group, but were significantly elevated in the patients with bacterial meningitis. The serum BDNF levels were elevated in all subgroups of patients with CNS infections, and the elevation was particularly notable in those with bacterial meningitis. BDNF expression in the CSF was correlated with CSF interleukin (IL)-6 levels as well as with blood platelet counts and neurological prognoses in those with bacterial meningitis. No correlation was found between BDNF levels and serum leukocyte numbers or C-reactive protein (CRP) levels. BDNF levels were found to be elevated in the serum and CSF of pediatric patients with CNS infections, particularly those with bacterial meningitis. Monitoring the changes in serum and CSF levels of BDNF may facilitate the diagnosis of acute meningitis and acute encephalopathy and allow the differential diagnosis of specific CNS infections.

Usefulness of nested PCR and sequence analysis in a nosocomial outbreak of neonatal enterovirus infection

BACKGROUND

Non-polio enterovirus infections are recognized in children during summer-fall seasons and they sometimes cause large outbreaks. We experienced a nosocomial infection in the neonatal nursery and echovirus type 7 was isolated from samples of four patients.

OBJECTIVES

We diagnosed the horizontal infection of four neonates by reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) and the nucleotide sequence.

STUDY DESIGN

Total RNA was extracted from clinical isolates, serum samples and cerebrospinal fluid (CSF). We amplified enterovirus genome in the 5'-noncoding region by nested PCR and determined the nucleotide sequences.

RESULTS

Enterovirus genome was detected in all isolates, in the acute-phase sera in all four patients and in the CSF in one patient by the first PCR. By using nested PCR, the genome was detected from convalescent-phase sera in two patients. All enterovirus genome obtained from the nursery outbreak showed the same sequences with 100% homology.

CONCLUSION

We demonstrated the clinical advantages of RT-nested PCR from serum samples and the analysis of nucleotide sequencing gave the supportive evidence of identification of transmission pathway.

Virological and immunological characteristics of a 19-year-old Japanese female with fatal outcome with Epstein-Barr virus-associated hemophagocytic syndrome

Hemophagocytic syndrome (HPS) is caused by the hyperactivation of T-cells and macrophages. The clinical characteristics associated with this disease result from overproduction of cytokines including interferon-gamma (INF-gamma), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6). HPS presents with fever, liver dysfunction, coagulation abnormalities, pancytopenia, and a benign histiocytic proliferation with prominent hemophagocytosis in bone marrow, lymph node, spleen, and liver. We describe a 19-year-old female with fatal HPS. She had been given corticosteroid every other day for systemic lupus erythematosus (SLE) without flare up. The causative underlying disease was acute primary Epstein-Barr virus (EBV) infection. EBV genomes were detected by the polymerase chain reaction (PCR). To measure the virus load we use a real-time PCR assay to quantify the amount of EBV DNA in peripheral blood lymphocytes, lung, kidney, brain and liver at autopsy. Further in situ hybridisation (ISH) and immunohistochemical studies demonstrated that Epstein-Barr virus encoded small RNA (EBER) was detected in CD8+ T-cells in bone marrow, lung, kidney, brain, liver and spleen. In each organ, mRNA levels of inflammatory cytokines (INF-gamma, TNF-alpha, IL-6) were highly detected compared with beta-Actin mRNA levels. These results suggest that EBV-infected CD8+ T-cells in each organ (peripheral blood lymphocytes, lung, kidney, brain and liver) may have an integral role in the pathophysiology of the HPS.

Different effects between 7-nitroindazole and L-NAME on cerebral hemodynamics and hippocampal lesions during kainic acid-induced seizures in newborn rabbits

We examined the effects of 7-nitroindazole (7-NI) and N-omega-nitro-L-arginine methyl ester (L-NAME) on the endogenous nitric oxide (NO) production in vivo, cerebral hemodynamics, and hippocampal lesions to investigate the different roles between endothelial NOS (eNOS) and neuronal NOS (nNOS) during kainic acid (KA)-induced seizures in newborn rabbits. After a pre-treatment with 7-NI (50 mg/kg, i.p.), L-NAME (20 mg/kg, i.v.) or saline (1 ml, i.v.), KA (12 mg/kg, i.v.) was administered. NO production in the brain, regional cerebral blood flow (rCBF), cerebral oxygenation (concentrations of oxyhemoglobin (HbO2), deoxyhemoglobin (HbR), and total hemoglobin (tHb) in the brain tissue), and electroencephalography (EEG) were continuously monitored throughout the experiment lasting at least 60 min after the KA administration. There was a significant increase in NO generation in the brain during KA-induced seizures, which was inhibited by a pre-treatment with 7-NI or L-NAME. KA-induced seizures also increased rCBF significantly, which was inhibited not by 7-NI but by L-NAME. L-NAME pre-treatment caused a significant decrease in HbO2 and a significant increase in HbR during KA-induced seizures, compared with 7-NI and saline pre-treatment. EEG abnormalities and Neuronal damages in the hippocampus were significantly lower in 7-NI- and L-NAME-treated animals respectively, than in saline-treated animals. The present data demonstrated that the selective nNOS inhibitor, 7-NI, attenuated neither rCBF nor cerebral oxygenation during the seizures, while the non-selective NOS (nNOS and eNOS) inhibitor, L-NAME, attenuated both. These findings suggest that NO, probably originating from eNOS, may play an important role in the cerebral circulation. Both 7-NI and L-NAME inhibited the NO production and EEG abnormalities during the seizures that led to less damage to the hippocampus.

Comparison of changes in cerebral and systemic perfusion between appropriate- and small-for-gestational-age infants during the first three days after birth

PURPOSE

The aims of the current study were to compare changes in cerebral and systemic perfusion in appropriate-for-gestational-age (AGA) and small-for-gestational-age (SGA) infants immediately after birth.

METHODS

Cerebral blood volume (CBV), cerebral Hb oxygen saturation (cSO2) and cerebral fractional tissue oxygen extraction (cFTOE) among 57 AGA infants and 30 SGA infants were monitored using a newly developed time-resolved spectroscopy system during the first 3days of life. The left ventricular ejection fraction (LVEF), left ventricular cardiac output (LVCO) and E/e' values were determined by three-dimensional echocardiography and tissue Doppler imaging performed simultaneously.

RESULTS

There were significant differences between the body weights of both the AGA and SGA infants, but not between the gestational age and head circumferences in both groups. Although CBV showed no significant difference between the groups, cSO2 was significantly higher and cFTOE was lower in SGA infants than in AGA infants. Hematocrit (Ht) levels were significantly higher and LVEF and LVCO were lower in SGA infants than in AGA infants. Negative correlation was observed between CBV and Ht levels in AGA infants, but not in SGA infants.

CONCLUSIONS

The high Ht levels and vasoreactivity in SGA infants might be a compensatory mechanism in order to maintain oxygen delivery to the brain, which reflects the condition of chronic hypoxia during the fetal period and also reflects the weak contraction and low cardiac output of the left ventricle sustaining the relatively large brain from the fetal period to after birth.

Hypothermia during kainic acid-induced seizures reduces hippocampal lesions and cerebral nitric oxide production in immature rabbits

We investigated (1) whether cerebral hypothermia during kainic acid (KA)-induced seizures was neuroprotective; and (2) whether nitric oxide (NO) production in the brain during seizures was altered by cerebral hypothermia in immature rabbits. Twelve female rabbits, aged 2 weeks, were anesthetized, paralyzed and mechanically ventilated. We continuously measured NO production in the brain by NO-selective electrode, cortical electroencephalogram (EEG), regional cerebral blood flow (rCBF) by laser Doppler flowmetry, rectal and cerebral temperatures and mean arterial blood pressure (MABP) during KA (12 mg/kg, i.v.)-induced seizures in the hypothermic group (n = 6; rectal temperature, 33 degrees C), and in the normothermic group (n = 6; rectal temperature, 37 degrees C). The normothermic group showed a gradual increase in NO generation in the brain, which was significantly inhibited in the hypothermic group. There were no significant differences in the increases in rCBF, MABP, arterial blood gases, blood glucose, or EEG abnormalities between the two groups. Neuronal damages in the hippocampus (CA3) were significantly lower in hypothermia than in normothermia. These results suggest that hypothermia attenuates NO production during drug-induced seizures and decreases hippocampal brain lesions in the immature rabbit brain. These results may help to explain the neuroprotective effects of hypothermia.

Association and synergistic interaction between promoter variants of the DRD4 gene in Japanese schizophrenics

Recent association studies suggest that polymorphisms in the promoter and exon 1 upstream region of the dopamine D4 receptor (DRD4) gene play a functional role in the development of common psychiatric illnesses, although there are also conflicting results. In this study, we re-sequenced this region to identify all genomic variants, and tested them for association with schizophrenia. A total of 570 Japanese schizophrenic cases with matched controls were studied by genotyping all identified/validated common polymorphisms (−1106T>C, −906T>C, −809G>A, −616G>C, −521T>C, −376C>T, −291C>T and 12-bp repeat) and a known microsatellite (120-bp tandem duplication) in the upstream region. A single nucleotide polymorphism (SNP) −809G>A in the promoter region was found to be significantly associated with disease (P=0.018 and 0.032 for allelic and genotypic comparisons, respectively), although not surviving after Bonferroni correction. Logistic regression analysis showed that a combination of the four polymorphisms, −809G>A, −616G>C, −291C>T and the 12-bp repeat, conferred a susceptibility to schizophrenia. These results suggest that the upstream variants have a primary functional effect in the etiology of schizophrenia in the Japanese population.

Polymerase chain reaction detection of the hemagglutinin gene from an attenuated measles vaccine strain in the peripheral mononuclear cells of children with autoimmune hepatitis

We examined the measles H gene using reverse transcriptase-polymerase chain reaction in peripheral mononuclear cells obtained from 4 pediatric and 2 adult patients with autoimmune hepatitis and 12 healthy children who had been infected with measles or vaccinated with an attenuated measles vaccine in the past. All patients were positive for the presence of the gene. Only one healthy control, who had been vaccinated two weeks before the study, was positive, while the other 11 controls were negative for the presence of the gene. The restriction enzyme patterns of the products in the pediatric patients were different from those observed in adults. The sequences of amplified products from pediatric patients coincided with the vaccine strain, whereas those from adults were different from the vaccine strain. The sequence of those from one of two adult patients was similar to those of the isolates in 1990 and later. Our results demonstrated that children with autoimmune hepatitis can have persistence of the vaccine strain in vivo for many years after vaccination.