Polyunsaturated fatty acid deficiency during neurodevelopment in mice models the prodromal state of schizophrenia through epigenetic changes in nuclear receptor genes

The risk of schizophrenia is increased in offspring whose mothers experience malnutrition during pregnancy. Polyunsaturated fatty acids (PUFAs) are dietary components that are crucial for the structural and functional integrity of neural cells, and PUFA deficiency has been shown to be a risk factor for schizophrenia. Here, we show that gestational and early postnatal dietary deprivation of two PUFAs-arachidonic acid (AA) and docosahexaenoic acid (DHA)-elicited schizophrenia-like phenotypes in mouse offspring at adulthood. In the PUFA-deprived mouse group, we observed lower motivation and higher sensitivity to a hallucinogenic drug resembling the prodromal symptoms in schizophrenia. Furthermore, a working-memory task-evoked hyper-neuronal activity in the medial prefrontal cortex was also observed, along with the downregulation of genes in the prefrontal cortex involved in oligodendrocyte integrity and the gamma-aminobutyric acid (GABA)-ergic system. Regulation of these genes was mediated by the nuclear receptor genes Rxr and Ppar, whose promoters were hyper-methylated by the deprivation of dietary AA and DHA. In addition, the RXR agonist bexarotene upregulated oligodendrocyte- and GABA-related gene expression and suppressed the sensitivity of mice to the hallucinogenic drug. Notably, the expression of these nuclear receptor genes were also downregulated in hair-follicle cells from schizophrenia patients. These results suggest that PUFA deficiency during the early neurodevelopmental period in mice could model the prodromal state of schizophrenia through changes in the epigenetic regulation of nuclear receptor genes.

Immunoglobulin A deficiency following treatment with lamotrigine

Lamotrigine (LTG) is an anti-epileptic drug and mood-stabilizing agent, whose adverse effects include skin rash and dizziness. Interactions with the immune system are rare, and only a few cases linking hypogammaglobulinemia to LTG treatment have been previously described. In this report, we describe a case in which a patient developed hypogammaglobulinemia, and a subsequent immunoglobulin A (IgA) deficiency, following LTG treatment. As a result of her immunodeficiency, the patient presented with a severe urinary tract infection and required intravenous immunoglobulin. Serum levels of immunoglobulin G and M had recovered by seven months and one month after the discontinuation of LTG, respectively; however, IgA levels remained low (less than 4mg/dL) two years post-treatment. While previous reports have demonstrated IgA deficiencies in patients prescribed other antiepileptic drugs, this is the first case of an IgA deficiency following LTG administration.

Distinguishing Acute Encephalopathy with Biphasic Seizures and Late Reduced Diffusion from Prolonged Febrile Seizures by Acute Phase EEG Spectrum Analysis

BACKGROUND

To differentiate the features of electroencephalography (EEG) after status epileptics in febrile children with final diagnosis of either febrile seizure (FS) or acute encephalopathy for an early diagnosis.

METHODS

We retrospectively collected data from 68 children who had status epilepticus and for whom EEGs were recorded within 120 h. These included subjects with a final diagnosis of FS (n = 20), epileptic status (ES; n = 11), acute encephalopathy with biphasic seizures and late reduced diffusion (AESD; n = 18), mild encephalopathy with a reversible splenial lesion (MERS; n = 7), other febrile encephalopathies (n = 10), hypoxic-ischemic encephalopathy (n = 1), and intracranial bleeding (n = 1). Initially, all EEGs were visually assessed and graded, and correlation with outcome was explored. Representative EEG epochs were then selected for quantitative analyses. Furthermore, data from AESD (n = 7) and FS (n = 16) patients for whom EEG was recorded within 24 h were also compared.

RESULTS

Although milder and most severe grades of EEG correlated with neurological outcome, the outcome of moderate EEG severity group was variable and was not predictable from usual inspection. Frequency band analysis revealed that solid delta power was not significantly different among the five groups (AESD, MERS, FS, ES and control), and that MERS group showed the highest theta band power. The ratios of delta/alpha and (delta + theta)/(alpha + beta) band powers were significantly higher in the AESD group than in other groups. The alpha and beta band powers in EEGs within 24 h from onset were significantly lower in the AESD group. The band powers and their ratios showed earlier improvement towards 24 h in FS than in AESD.

CONCLUSION

Sequential EEG recording up to 24 h from onset appeared to be helpful for distinction of AESD from FS before emergence of the second phase of AESD.

22q11.2 deletion carriers and schizophrenia-associated novel variants

The penetrance of schizophrenia risk in carriers of the 22q11.2 deletion is high but incomplete, suggesting the possibility of additional genetic defects. We performed whole exome sequencing on two individuals with 22q11.2 deletion, one with schizophrenia and the other who was psychosis-free. The results revealed novel genetic variants related to neuronal function exclusively in the person with schizophrenia (frameshift: KAT8, APOH and SNX31; nonsense: EFCAB11 and CLVS2). This study paves the way towards a more complete understanding of variant dose and genetic architecture in schizophrenia.

Ceramide limits phosphatidylinositol-3-kinase C2β-controlled cell motility in ovarian cancer: potential of ceramide as a metastasis-suppressor lipid

Targeting cell motility, which is required for dissemination and metastasis, has therapeutic potential for ovarian cancer metastasis, and regulatory mechanisms of cell motility need to be uncovered for developing novel therapeutics. Invasive ovarian cancer cells spontaneously formed protrusions, such as lamellipodia, which are required for generating locomotive force in cell motility. Short interfering RNA screening identified class II phosphatidylinositol 3-kinase C2β (PI3KC2β) as the predominant isoform of PI3K involved in lamellipodia formation of ovarian cancer cells. The bioactive sphingolipid ceramide has emerged as an antitumorigenic lipid, and treatment with short-chain C6-ceramide decreased the number of ovarian cancer cells with PI3KC2β-driven lamellipodia. Pharmacological analysis demonstrated that long-chain ceramide regenerated from C6-ceramide through the salvage/recycling pathway, at least in part, mediated the action of C6-ceramide. Mechanistically, ceramide was revealed to interact with the PIK-catalytic domain of PI3KC2β and affect its compartmentalization, thereby suppressing PI3KC2β activation and its driven cell motility. Ceramide treatment also suppressed cell motility promoted by epithelial growth factor, which is a prometastatic factor. To examine the role of ceramide in ovarian cancer metastasis, ceramide liposomes were employed and confirmed to suppress cell motility in vitro. Ceramide liposomes had an inhibitory effect on peritoneal metastasis in a murine xenograft model of human ovarian cancer. Metastasis of PI3KC2β knocked-down cells was insensitive to treatment with ceramide liposomes, suggesting specific involvement of ceramide interaction with PI3KC2β in metastasis suppression. Our study identified ceramide as a bioactive lipid that limits PI3KC2β-governed cell motility, and ceramide is proposed to serve as a metastasis-suppressor lipid in ovarian cancer. These findings could be translated into developing ceramide-based therapy for metastatic diseases.

Myocerebrohepatopathy spectrum disorder due to POLG mutations: A clinicopathological report

We report on the clinical, neuropathological, and genetic findings of a Japanese case with myocerebrohepatopathy spectrum (MCHS) disorder due to polymerase gamma (POLG) mutations. A girl manifested poor sucking and failure to thrive since 4 months of age and had frequent vomiting and developmental regression at 5 months of age. She showed significant hypotonia and hepatomegaly. Laboratory tests showed hepatocellular dysfunction and elevated protein and lactate levels in the cerebrospinal fluid. Her liver function and neurologic condition exacerbated, and she died at 8 months of age. At autopsy, fatty degeneration and fibrosis were observed in the liver. Neuropathological examination revealed white matter-predominant spongy changes with Alzheimer type II glia and loss of myelin. Enzyme activities of the respiratory chain complex I, III, and IV relative to citrate synthase in the muscle were normal in the biopsied muscle tissue, but they were reduced in the liver to 0%, 10%, and 14% of normal values, respectively. In the liver, the copy number of mitochondrial DNA compared to nuclear DNA was reduced to 3.3% of normal values as evaluated by quantitative polymerase chain reaction. Genetic analysis revealed compound heterozygous mutations for POLG (I1185T/A957V). This case represents the differential involvement of multiple organs and phenotype-specific distribution of brain lesions in mitochondrial DNA depletion disorders.

Effects of antidiabetes drugs on functional independence measure on a subacute rehabilitation ward for stroke patients

It has been reported that the improvement of activities of daily living (ADL) by rehabilitation affects glycemic control. However, there are no reports about antidiabetes drugs as factors affecting the outcomes of rehabilitation. Therefore, we investigated the effects of antidiabetes drugs on functional independence measure (FIM) [total (T), motor (M), and cognition (C) items] in stroke patients with diabetes who were discharged from the subacute rehabilitation ward. We chose the frequently used antidiabetes drugs [sulfonylurea (SU), dipeptidyl peptidase-IV inhibitors (DPP-IVIs), and α-glycosidase inhibitors (α-GIs)] as the basis for categorizing the patients. We compared the patients' background features and laboratory data among the three groups. As a result, when SU was used in stroke patients with diabetes, it is difficult to obtain significant FIM-M gain, FIM-C gain, FIM-M efficiency, and FIM-C efficiency compared with of-GIs. As a reason for this, we hypothesize the possibility of the involvement of insulin resistance. Therefore, we consider that insulin resistance should be determined early and that it is important to reduce insulin resistance comprehensively by involving experts.

Early predictors of status epilepticus-associated mortality and morbidity in children

BACKGROUND

Early predictors of status epilepticus (SE)-associated mortality and morbidity have not been systematically studied in children, considerably impeding the identification of patients at risk.

OBJECTIVES

To determine reliable early predictors of SE-associated mortality and morbidity and identify the etiology of SE-associated sequelae in Japanese children.

METHODS

We conducted a prospective multicenter study of clinical findings and initial laboratory data acquired at SE onset, and assessed outcomes at the last follow-up examination. In-hospital death during the acute period and neurological sequelae were classified as poor outcomes.

RESULTS

Of the 201 children who experienced their first SE episode, 16 exhibited poor outcome that was most commonly associated with acute encephalopathy. Univariate analysis revealed that the following were associated with poor outcomes: young age (⩽24 months); seizure duration >90 min; seizure intractability (failure of the second anticonvulsive drug); biphasic seizures; abnormal blood glucose levels (<61 or >250 mg/dL); serum aspartate aminotransferase (AST) ⩾56 U/L; and C-reactive protein (CRP) levels >2.00 mg/dL. Multivariate analysis revealed that young age, seizure intractability, abnormal blood glucose levels, and elevated AST and CRP levels were statistically significant.

CONCLUSIONS

Young age and seizure intractability were highly predictive of poor outcomes in pediatric SE. Moreover, abnormal blood glucose levels and elevated AST and CRP levels were predictors that might be closely associated with the etiology, especially acute encephalopathy and severe bacterial infection (sepsis and meningitis) in Japanese children.

Pharmacoeconomic analysis of DPP-4 inhibitors

Dipeptidyl peptidase-4 (DPP-4) inhibitors and other incretin-related drugs have attracted attention as antidiabetic agents, but they are expensive. The Japanese government has adopted a policy of reducing healthcare costs, and medical institutions must provide medical care while considering economic efficiency. This study was a comparative survey of the usage, treatment effectiveness, and cost of DPP-4 inhibitors. The subjects were patients prescribed DPP-4 inhibitors (sitagliptin, vildagliptin, and alogliptin) at Gifu Municipal Hospital between February 2010 and August 2011. HbA1c: Japan Diabetes Society values (%) and concomitant antidiabetic agents were surveyed for 12 weeks after the start of DPP-4 inhibitors. A cost-effectiveness analysis showed that the cost required for a 0.1% decrease in HbA1c for 12 weeks was the lowest with vildagliptin (2,478 yen; decrease in HbA1c: 0.75% +/- 0.85%). In a cost analysis with a virtual cohort of 1000 patients, the number of patients who achieved the treatment target (HbA1c 6.5%) was estimated with respect to a virtual cohort created based on the HbA1c level (7.59 +/- 1.13%) at baseline of 307 patients, in cases assuming the use of each DPP-4 inhibitor. In addition, the incremental cost-effectiveness ratio (ICER) was obtained with sitagliptin 50 mg as the reference. The number of patients achieving the treatment target was the highest with vildagliptin 100 mg (413 of 1000 patients), and the estimated ICER of 28,359 yen was the lowest. Robustness was also confirmed with a sensitivity analysis. These results suggest that vildagliptin provides a superior cost-benefit.

Association of acute cerebellar ataxia and human papilloma virus vaccination: a case report

INTRODUCTION

We report the case of a patient who developed symptoms of acute cerebellar ataxia (ACA) after administration of the human papilloma virus (HPV)-16/18 vaccine.

PATIENT AND METHOD

This patient developed symptoms of ACA, including nausea, vertigo, severe limb and truncal ataxia, and bilateral spontaneous continuous horizontal nystagmus with irregular rhythm, 12 days after administration of the HPV-16/18 AS04-adjuvanted cervical cancer vaccine. After this, the patient received methylprednisolone pulse and intravenous immunoglobulin (IVIG) therapies as well as immunoadsorption plasmapheresis.

RESULTS

Severe ACA symptoms did not improve after methylprednisolone pulse and IVIG therapies, but the patient recovered completely after immunoadsorption plasmapheresis.

CONCLUSION

This temporal association strongly suggests that ACA was induced by the vaccination.

ADORA2A polymorphism predisposes children to encephalopathy with febrile status epilepticus

OBJECTIVE

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a childhood encephalopathy following severe febrile seizures, leaving neurologic sequelae in many patients. However, its pathogenesis remains unclear. In this study, we clarified that genetic variation in the adenosine A2A receptor (ADORA2A), whose activation is involved in excitotoxicity, may be a predisposing factor of AESD.

METHODS

We analyzed 4 ADORA2A single nucleotide polymorphisms in 85 patients with AESD. The mRNA expression in brain samples, mRNA and protein expression in lymphoblasts, as well as the production of cyclic adenosine monophosphate (cAMP) by lymphoblasts in response to adenosine were compared among ADORA2A diplotypes.

RESULTS

Four single nucleotide polymorphisms were completely linked, which resulted in 2 haplotypes, A and B. Haplotype A (C at rs2298383, T at rs5751876, deletion at rs35320474, and C at rs4822492) frequency in patients was significantly higher than in controls (p = 0.005). Homozygous haplotype A (AA diplotype) had a higher risk of developing AESD (odds ratio 2.32, 95% confidence interval 1.32-4.08; p = 0.003) via a recessive model. mRNA expression was significantly higher in AA than AB and BB diplotypes, both in the brain (p = 0.003 and 0.002, respectively) and lymphoblasts (p = 0.035 and 0.003, respectively). In lymphoblasts, ADORA2A protein expression (p = 0.024), as well as cellular cAMP production (p = 0.0006), was significantly higher in AA than BB diplotype.

CONCLUSIONS

AA diplotype of ADORA2A is associated with AESD and may alter the intracellular adenosine/cAMP cascade, thereby promoting seizures and excitotoxic brain damage in patients.

Quantitative computed tomography for enzyme replacement therapy in Pompe disease

OBJECTIVE

Pompe disease is an autosomal recessive disorder caused by deficiency of the lysosomal enzyme, acid alpha-glucosidase (GAA). To the best of our knowledge, no studies have reported the results of systematic and sequential CT analyses before and during ERT. In this study we have treated three patients with late onset Pompe disease by ERT, and investigated the efficacy of treatment by computed tomography number.

METHODS

We measured the serial changes in the computed tomography (CT) number of multiple organs in three patients with late onset of Pompe disease during 24 months of enzyme replacement therapy (ERT).

RESULTS

Before treatment, the liver and muscle CT numbers were higher in these patients than in the controls. The liver CT number decreased after performing ERT. Furthermore, the urinary glucose tetrasaccharide levels, a biomarker of glycogen accumulation, were elevated before ERT and reduced thereafter.

CONCLUSIONS

The findings in these cases suggest that the elevation of the liver CT number represents glycogen accumulation in the liver and that the analysis of the liver CT number is therefore a useful tool for assessing the efficacy of ERT.

Three Japanese Patients with Beta-Ketothiolase Deficiency Who Share a Mutation, c.431A>C (H144P) in ACAT1 : Subtle Abnormality in Urinary Organic Acid Analysis and Blood Acylcarnitine Analysis Using Tandem Mass Spectrometry

Mitochondrial acetoacetyl-CoA thiolase (T2) deficiency affects both isoleucine catabolism and ketone body metabolism. The disorder is characterized by intermittent ketoacidotic episodes. We report three Japanese patients. One patient (GK69) experienced two ketoacidotic episodes at the age of 9 months and 3 years, and no further episodes until the age of 25 years. She had two uncomplicated pregnancies. GK69 was a compound heterozygote of the c.431A>C (H144P) and c.1168T>C (S390P) mutations in T2 (ACAT1) gene. She was not suspected of having T2 deficiency during her childhood, but she was diagnosed as T2 deficient at the age of 25 years by enzyme assay using fibroblasts. The other two patients were identical twin siblings who presented their first ketoacidotic crisis simultaneously at the age of 3 years 4 months. One of them (GK77b) died during the first crisis and the other (GK77) survived. Even during severe crises, C5-OH and C5:1 were within normal ranges in their blood acylcarnitine profiles and trace amounts of tiglylglycine and small amounts of 2-methyl-3-hydroxybutyrate were detected in their urinary organic acid profiles. They were H144P homozygotes. This H144P mutation has retained the highest residual T2 activity in the transient expression analysis of mutant cDNA thus far, while the S390P mutation did not retain any residual T2 activity. The "mild" H144P mutation may result in subtle profiles in blood acylcarnitine and urinary organic acid analyses. T2-deficient patients with "mild" mutations have severe ketoacidotic crises but their chemical phenotypes may be subtle even during acute crises.

Transethmoidal meningoencephalocele involving the olfactory bulb with enlarged foramina of the lamina cribrosa--case report

A 3-year-old girl presented with a transethmoidal meningoencephalocele manifesting as recurrent rhinorrhea. Initially, she developed meningitis, but after treatment she experienced rhinorrhea. Two months later, she again presented with rhinorrhea. Neuroimaging studies revealed a small protrusion (15 mm x 10 mm) at the roof of the ethmoidal sinus. Nasal endoscopy confirmed the diagnosis of meningoencephalocele. The operative findings revealed a small hole in the left olfactory bulb, which had descended into an enlarged foramen along with the arachnoid membrane. The left olfactory bulb was removed, and the enlarged foramina of the lamina cribrosa were covered with a frontal pericranial flap. The defect in the bone was very small, but contributed to the development of meningitis and leakage of the cerebrospinal fluid. Basal cephalocele should be considered in a patient with recurrent rhinorrhea and intracranial infections, even in the absence of any apparent anomaly.

Vertebral fusion in a patient with supernumerary-der(22)t(11;22) syndrome

A patient with a 47,XX,+der(22)t(11;22)(q23.3;q11.2) karyotype exhibited brisk tendon reflex and Babinski sign with suggested pyramidal sign. A three-dimensional computed tomographic reconstruction revealed a T1-T2 vertebral fusion without hemivertebrae. Sagittal magnetic resonance imaging revealed degenerative disk changes, mild disk herniation, and mild spinal cord compression. Congenital vertebral fusion may be one of the anomalies in supernumerary-der(22)t(11;22) syndrome. Once clinical diagnosis of this chromosome aberration is established, radiologic evaluation of vertebrae and spinal neuroimaging should be performed.

Mental retardation, spasticity, basal ganglia calcification, cerebral white matter lesions, multiple endocrine defects, telangiectasia and atrophic skin: a new syndrome?

We report on an 8-year-old boy with mental retardation and spastic tetraparesis associated with atrophic skin on the face and extremities, telangiectasia, and severe dental caries. Basal ganglia calcification and multiple lesions in the subcortical white matter have been present since infancy. The patient has complications of liver dysfunction, multiple endocrine defects, and elevation of blood/cerebrospinal fluid lactate. Extensive laboratory examinations, including skin and muscle biopsies, and UV- and mitomycin C-sensitivity tests on fibroblasts, provided no evidence of a specific disease entity. No deterioration was noted, and supplementation of riboflavin and other vitamins had no apparent effect on the neurodevelopmental status of this patient. This patient may represent a novel disease entity, with unclear pathogenesis.

Antiphospholipid syndrome associated with human herpesvirus-6 infection

The case of a patient with basal ganglia infarction associated with primary human herpesvirus-6 infection is reported. Anticardiolipin antibody immunoglobulin G was elevated after human herpesvirus-6 infection and then decreased gradually. The transient elevation in the antiphospholipid antibody level suggests that the human herpesvirus-6 infection can induce antiphospholipid syndrome, thus resulting in a cerebral infarction.

Chromosome aberrations do not persist in the lymphocytes or bone marrow cells of mice irradiated in utero or soon after birth

Mice were exposed at various ages to 1 Gy or 2 Gy of X rays, and translocation frequencies in peripheral blood T cells, spleen cells, and bone marrow cells were determined with FISH painting of chromosomes 1 and 3 when the animals were 20 weeks old. It was found that the mean translocation frequencies were very low (< or =0.8%) in mice exposed in the fetal or early postnatal stages. However, with the increase in animal age at the time of irradiation, the frequency observed at 20 weeks old became progressively higher then reached a plateau (about 5%) when mice were irradiated when > or =6 weeks old. A major role of p53 (Trp53)-dependent apoptosis for elimination of aberrant cells was not suggested because irradiated fetuses, regardless of the p53 gene status, showed low translocation frequencies (1.8% in p53(-/-) mice and 1.4% in p53(+/-) mice) compared to the frequency in the p53(-/-) mother (7.4%). In contrast, various types of aberrations were seen in spleen and liver cells when neonates were examined shortly after irradiation, similar to what was observed in bone marrow cells after irradiation in adults. We interpreted the results as indicating that fetal cells are generally sensitive to induction of chromosome aberrations but that the aberrant cells do not persist because fetal stem cells tend to be free of aberrations and their progeny replace the pre-existing cell populations during the postnatal growth of the animals.

p21 provides stage specific DNA damage control to preimplantation embryos

The early stage embryogenesis of higher eukaryotes lacks some of the damage response pathways such as G1/S checkpoint, G2/M checkpoint and apoptosis. We examined here the damage response of preimplantation stage embryos after fertilization with 6 Gy irradiated sperm. Sperm-irradiated embryos developed normally for the first 2.5 days, but started to exhibit a developmental delay at day 3.5. p21 was activated in the delayed embryos, which carried numerous micronuclei owing to delayed chromosome instability. Apoptosis was observed predominantly in the inner cell mass of the day 4.0 embryos. Sperm-irradiated p21-/- embryos lacked the delay, but chromosome instability and apoptosis were more pronounced than the corresponding p21 wild-type embryos. We conclude from the result that damage responses come in a stage-specific manner during preimplantation stage development; p53-dependent S checkpoint at the zygote stage, p21-mediated cell cycle arrest at the morula/blastocyst stages and apoptosis after the blastocyst stage in the inner cell mass.

[Pulmonary atelectasis in patients with neurological or muscular disease; gravity-related lung compression by the heart and intra-abdominal organs on persistent supine position]

We report 10 cases of pulmonary atelectasis diagnosed by chest computed tomography in patients with neurological or muscular disease. Atelectasis was frequently seen in hypotonic patients who could not roll over on their own. The atelectases located mostly in the dorsal bronchopulmonary segments, adjacent to the heart or diaphragm. Atelectasis diminished in two patients after they became able to roll themselves over. Gravity-related lung compression by the heart and intra-abdominal organs on persistent supine position can cause pulmonary atelectasis in patients with neurological or muscular disease who can not roll over by their own power. To confirm that the prone position reduces compression of the lungs, chest computed tomography was performed in both the supine and the prone position in three patients. Sagittal images with three-dimensional computed tomographic reconstruction revealed significant sternad displacements of the heart and caudal displacements of the dorsal portion of the diaphragm on prone position compared with supine position. The prone position, motor exercises for rolling over, and biphasic cuirass ventilation are effective in reducing gravity-related lung compression. Some patients with intellectual disabilities were also able to cooperate in chest physiotherapy. Chest physiotherapy is useful in preventing atelectasis in patients with neurological or muscular disease.

Interstitial lung diseases associated with amyopathic dermatomyositis

The aim of the present study was to clarify the clinical characteristics and prognosis of patients with interstitial lung disease (ILD) associated with amyopathic dermatomyositis (ILD-ADM). The study consisted of 14 consecutive patients with ILD-ADM. Patients were classified into two categories, acute/subacute and chronic forms, according to the clinical presentation of ILD. The clinical features, responsiveness to therapy, and prognosis between the two forms were compared. Nine ILD-ADM patients were categorised as the acute/subacute form, and five as the chronic form. Arterial oxygen tension was significantly lower in the acute/subacute ILD than chronic ILD patients. On high-resolution computed tomography, ground-glass opacities were frequently found in the two forms, but consolidation was more common in acute/subacute ILD than chronic ILD. Bronchoalveolar lavage analysis showed higher numbers of total cells and lymphocytes in acute/subacute ILD than chronic ILD. Histologically, the most common finding was nonspecific interstitial pneumonia in the two forms, while diffuse alveolar damage was only found in acute/subacute ILD. Acute/subacute ILD was generally resistant to therapy, while chronic ILD responded well. Notably, the mortality of acute/subacute ILD was much higher than that of chronic ILD (67 versus 0%, respectively). In conclusion, interstitial lung disease associated with amyopathic dermatomyositis includes two different forms, the acute/subacute and chronic forms, with distinct prognoses.

Paclitaxel-platinum combination chemotherapy for advanced or recurrent ovarian clear cell adenocarcinoma: a multicenter trial

The therapeutic effect of a combination of paclitaxel (PTX) and platinum (PLT) in ovarian clear cell adenocarcinoma (CC) patients with measurable disease has yet to be elucidated. In this study, we used retrospective review to evaluate the results of treatment with a combination of PTX and PLT in CC patients with measurable disease. A total of 28 patients with measurable residual CC (15 cases with primary disease, 13 cases with recurrent disease) treated with combination PTX-PLT chemotherapy was identified through medical records from ten institutions. Clinical response to chemotherapy was evaluated using Response Evaluation Criteria in Solid Tumors criteria. Of the 28 cases, 8 of 15 patients with primary disease (53.3%) and 3 of 13 patients with recurrent disease (23.1%) responded to PTX-PLT chemotherapy. The response rate for cases with late recurrent disease (>12 months) was 20% (1/5), whereas the rate was 25% (2/8) for cases with early recurrent (<12 months) or refractory disease. Our results indicate that the combination of PTX and PLT may have greater efficacy against CC than conventional PLT-based chemotherapy that does not include PTX.

Suppression of replication fork progression in low-dose-specific p53-dependent S-phase DNA damage checkpoint

The S-phase DNA damage checkpoint is activated by DNA damage to delay DNA synthesis allowing time to resolve the replication block. We previously discovered the p53-dependent S-phase DNA damage checkpoint in mouse zygotes fertilized with irradiated sperm. Here, we report that the same p53 dependency holds in mouse embryonic fibroblasts (MEFs) at low doses of irradiation. DNA synthesis in p53 wild-type (WT) MEFs was suppressed in a biphasic manner in which a sharp decrease below 2.5 Gy was followed by a more moderate decrease up to 10 Gy. In contrast, p53-/- MEFs exhibited radioresistant DNA synthesis below 2.5 Gy whereas the cells retained the moderate suppression above 5 Gy. DNA fiber analysis revealed that 1 Gy irradiation suppressed replication fork progression in p53 WT MEFs, but not in p53-/- MEFs. Proliferating cell nuclear antigen (PCNA), clamp loader of DNA polymerase, was phosphorylated in WT MEFs after 1 Gy irradiation and redistributed to form foci in the nuclei. In contrast, PCNA was not phosphorylated and dissociated from chromatin in 1 Gy-irradiated p53-/- MEFs. These results demonstrate that the novel low-dose-specific p53-dependent S-phase DNA damage checkpoint is likely to regulate the replication fork movement through phosphorylation of PCNA.

[Polycystic ovary syndrome and hepatocellular adenoma related to long-term use of sodium valproate in a young woman]

Previous studies have reported a high prevalence of polycystic ovary syndrome (PCOS) among women taking sodium valproate (VPA). We report the case of a 28 year-old epileptic female taking VPA, who developed PCOS and later hepatocellular adenoma. She had been taking VPA for intractable epilepsy since the age of 15 months. At the age of 22 years, she suffered spontaneous rupture of a liver tumor that was diagnosed as hepatocellular adenoma. At the age of 24 years, bilateral polycystic ovaries were found by transabdominal ultrasonography, and PCOS was diagnosed. VPA may directly influence steroidogenesis in the ovary and cause hyperandrogenemia with ensuing PCOS. It is known that abnormality in the sex hormones contributes to the onset of hepatocellular adenoma. Therefore, we speculate that hyperandrogenemia due to VPA contributed to the development of hepatocellular adenoma in this case.

Involvement of M(2) muscarinic receptors in relaxant response of circular muscle of mouse gastric antrum

Our previous study showed that atropine significantly inhibited the sustained relaxation induced by electrical field stimulation (EFS) in the circular muscle strips prepared from the mouse antrum, and that pituitary adenylate cyclase activating peptide (PACAP) partially mediated the sustained relaxation. The muscarinic receptor subtype associated with the sustained relaxation was examined in the present study by using each muscarinic receptor subtype of knockout (KO) mice. EFS-induced sustained relaxation in the antrum prepared from M(2) receptor KO mice was significantly less than that of wild-type mice. Atropine failed to inhibit this relaxation. On the other hand, similar sustained relaxation and inhibitory effects of atropine to those of wild-type mice were observed in M(1), M(3) and M(4) receptor KO mice. Exogenously added PACAP-27 relaxed the antral strips of wild-type and M(2) receptor KO mice to a similar extent. Immunohistochemical study revealed that M(2) receptor immunoreactivity was localized with PACAP-immunoreactivity in enteric neurons within the antrum of wild-type mice. In contrast, atropine did not affect the EFS-induced sustained relaxation in the gastric fundus. These results suggest that M(2) receptors modulate the sustained relaxation, probably through the regulation of PACAP release, in the mouse antrum.

Monozygotic twins discordant for Klippel-Feil syndrome

In a pair of Japanese monozygotic twins, one manifested Klippel-Feil syndrome, a short neck with C(1-4) vertebra fusion, whereas the other was normal. The discordance between the twins suggests that Klippel-Feil syndrome results in part from a postzygotic somatic mutation or intrauterine environmental factors.

Thiamine-responsive congenital lactic acidosis: clinical and biochemical studies

We studied six infants with thiamine-responsive congenital lactic acidosis and normal pyruvate dehydrogenase complex activity in vitro, through clinical and biochemical analysis. In addition to elevated lactate and pyruvate levels, the data revealed increased urinary excretion of alpha-ketoglutarate, alpha-ketoadipate, and branched chain ketoacids, indicating functional impairment of thiamine-requiring enzymes, such as pyruvate dehydrogenase complex, alpha-ketoglutarate dehydrogenase complex, alpha-ketoadipate dehydrogenase, and branched chain amino acid dehydrogenase. The metabolism of thiamine has not been investigated in patients with thiamine-responsive congenital lactic acidosis. We evaluated two specific transport systems, THTR-1 (SLC19A2) and THTR-2 (SLC19A3), and a pyrophosphorylating enzyme of thiamine, thiamine pyrophosphokinase (hTPK 1), in addition to pyruvate dehydrogenase complex and alpha-ketoglutarate dehydrogenase complex activity; no abnormality was found. Although the clinical features of thiamine-responsive congenital lactic acidosis are heterogeneous and clinical responses to thiamine administration vary, we emphasize the importance of early diagnosis and initiation of thiamine therapy before the occurrence of permanent brain damage. Careful monitoring of lactate and pyruvate would be useful in determining thiamine dosage.

[A case of left thalamic infarction with aphasia and dysgraphia in Kanji]

We reported an 11-year-old girl with left thalamic infarction causing aphasia and dysgraphia. The lesion corresponded to the perfusion area of the tuberothalamic and paramedian arteries. Confrontation naming and word finding were impaired, but phonological cuing was very helpful despite the absence of amnesia. Dysgraphia was observed only in Kanji (morphogram) writing, and was also improved by visual cuings. These findings suggested difficulty in memory retrieval, in which the left thalamus might have some role.

Heparanase protein and gene expression in bladder cancer

PURPOSE

We determined the association of heparanase protein and messenger (m)RNA expression with bladder cancer invasion and metastasis.

MATERIALS AND METHODS

The expression of heparanase protein and mRNA was assessed by immunohistochemical staining and in situ hybridization, respectively, in 67 bladder cancer specimens resected at various stages of disease. To our knowledge this is the first systematic study of heparanase protein and mRNA expression in human bladder cancer.

RESULTS

The expression of heparanase protein in muscular invasive bladder cancer was significantly higher than in superficial cancer (68% versus 19%, p = 0.0001). It was higher in the primary tumor of patients with lymph node metastatic cancer than those with nonmetastatic cancer (80% versus 37%, p = 0.0006). In high grade disease it was significantly higher than in low grade disease (79% versus 29%, p = 0.0001). The expression of heparanase mRNA was also significantly higher in stage pT3 or greater than in stage pT2 or less bladder cancer (96% versus 33%, p = 0.0003). In metastatic N+ cases it was significantly higher than in nonmetastatic bladder cancer (93% versus 46%, p = 0.0037). The heparanase gene and protein showed similar patterns of expression in bladder cancer.

CONCLUSIONS

Our study implies that the expression of heparanase protein and mRNA is associated with bladder cancer invasion and metastasis, and heparanase may have a role in disease progression.

Mutual alignment errors due to the variation of wave-front aberrations in a free-space laser communication link

Optical devices in free-space laser communication systems are affected by their environment, particularly in relation to the effects of temperature while in orbit. The mutual alignment error between the transmitted and received optical axes is caused by deformation of the optics due to temperature variation in spite of the common optics used for transmission and reception of the optical beams. When a Gaussian beam wave for transmission is aligned at the center of a received plane wave, 3rd-order Coma aberrations have the most influence on the mutual alignment error, which is an inevitable open pointing error under only the Tip/Tilt tracking control. As an example, a mutual alignment error of less than 0.2 microrad is predicted for a laser communication terminal in orbit using the results from space chamber thermal vacuum tests. The relative power penalty due to aberration is estimated to be about 0.4 dB. The results will mitigate surface quality in an optical antenna and contribute to the design of free-space laser communication systems.

Expression of three extracellular matrix degradative enzymes in bladder cancer

The relationship between expression of extracellular matrix degradative enzymes, angiogenesis and survival of multistage bladder cancer was determined. Expression of 3 extracellular matrix degradative enzymes (metalloproteinase-2, -9 and heparanase) and microvessel formation were examined in 40 resected bladder cancer specimens by immunohistostochemic staining, and then the association of the enzyme expression with angiogenesis and various stages of cancer was investigated. Heparanase protein expression in muscular invasive or lymph-node metastatic cancer was significantly higher than in superficial or nonmetastatic cancer, respectively (69% vs. 8%, p < 0.001, and 80% vs. 40%, p = 0.028, respectively). Interestingly, heparanase was expressed at much higher levels than matrix metalloproteinase-2 and -9. The mean microvessel count in cancers with heparanase expression was significantly higher than that in cancers without heparanase expression (32.3 +/- 18.2 vs. 5.5 +/- 6.1, p = 0.0008). The microvessel formation was not associated with the expression of matrix metalloproteinase-2 and -9. The cancer-specific and overall survival rates of patients with heparanase expression were significantly lower than those of patients without it (p = 0.0001 and p = 0.0008, respectively). Multivariate analysis showed that heparanase expression was a significantly independent prognostic factor for both cancer-specific (p = 0.0047) and overall survival (p = 0.0200). Our study suggested that heparanase plays important roles in invasion, angiogenesis and metastasis of bladder cancer, and thus, this molecule could be a new molecule to inhibit invasion, angiogenesis and metastasis of bladder cancer. Moreover, our results indicate that expression of heparanase could be a new prognostic factor of this disease.

Expression of three extracellular matrix degradative enzymes in bladder cancer

The relationship between expression of extracellular matrix degradative enzymes, angiogenesis and survival of multistage bladder cancer was determined. Expression of 3 extracellular matrix degradative enzymes (metalloproteinase-2, -9 and heparanase) and microvessel formation were examined in 40 resected bladder cancer specimens by immunohistostochemic staining, and then the association of the enzyme expression with angiogenesis and various stages of cancer was investigated. Heparanase protein expression in muscular invasive or lymph-node metastatic cancer was significantly higher than in superficial or nonmetastatic cancer, respectively (69% vs. 8%, p < 0.001, and 80% vs. 40%, p = 0.028, respectively). Interestingly, heparanase was expressed at much higher levels than matrix metalloproteinase-2 and -9. The mean microvessel count in cancers with heparanase expression was significantly higher than that in cancers without heparanase expression (32.3 +/- 18.2 vs. 5.5 +/- 6.1, p = 0.0008). The microvessel formation was not associated with the expression of matrix metalloproteinase-2 and -9. The cancer-specific and overall survival rates of patients with heparanase expression were significantly lower than those of patients without it (p = 0.0001 and p = 0.0008, respectively). Multivariate analysis showed that heparanase expression was a significantly independent prognostic factor for both cancer-specific (p = 0.0047) and overall survival (p = 0.0200). Our study suggested that heparanase plays important roles in invasion, angiogenesis and metastasis of bladder cancer, and thus, this molecule could be a new molecule to inhibit invasion, angiogenesis and metastasis of bladder cancer. Moreover, our results indicate that expression of heparanase could be a new prognostic factor of this disease.

[Mitochondrial DNA T to G mutation 8993 in Leigh encephalopathy and organic aciduria]

We report a 10-month-old female infant with Leigh encephalopathy caused by a T to G mutation at nucleotide 8993 of mitochondrial DNA. Initial manifestations were diarrhea and pyrexia, followed by disturbance of consciousness. Blood chemistry showed lactic acidosis, and cranial T2 weighted magnetic resonance imaging demonstrated symmetric high-intensity areas in the basal ganglia, consistent with Leigh encephalopathy. Analysis of urinary organic acids revealed a increase of alpha-ketoglutamate. Derivatives of branched chain amino acids, which accumulate in maple syrup disease, were also increased. Lipoamide dehydrogenase (E3) deficiency was initially suspected; however, normal activity of pyruvate dehydrogenase complex excluded the diagnosis. The organic aciduria disappeared after two weeks. The CNS lesions in our case were observed more prominently in the floor of the bilateral frontal lobes than in the globus pallidus and putamen. In this case, mitochondrial DNA mutation may have caused organic aciduria and the atypical imaging findings.

Wegener's granulomatosis responding to antituberculous drugs

We present a case of Wegener's granulomatosis (WG) that responded to antituberculous drugs. A 44-year-old woman with multiple nodules on chest radiograph received a diagnosis of pulmonary tuberculosis because open-lung biopsy specimens showed caseous granulomas. Her chest shadows underwent repeated resolution after the start of antituberculous treatment, and relapse after the cessation of the drugs. Antineutrophil cytoplasmic antibody was positive (14 enzyme-linked immunosorbent assay units), and the second lung biopsy specimens showed necrotizing granulomas and vasculitis without pathogenic organisms. Thus, the patient received a diagnosis of WG and was successfully treated with trimethoprim/sulfamethoxazole 10 years after her initial evaluation. Antituberculous drugs were effective in this case of WG.

Minimally invasive lung and pleural biopsies using 2-mm and standard thoracoscopic equipment

Videoendoscopic surgery is commonly used to obtain a definitive diagnosis in a patient with pleural lesions or pulmonary infiltration of unknown etiology. We have performed minimally invasive pleural and lung biopsies, using 2-mm mini-videoscopic instruments supported by standard thoracoscopy via one 11.5-mm port, in 10 patients. These involved 8 patients with diffuse pulmonary infiltration, and two with diffuse pleural thickening. They underwent thoracoscopic pulmonary wedge resection and pleural biopsy using one 11.5-mm port and two or three 2-mm mini-ports. The mean operating time was 37 minutes. This procedure was successful in establishing a definitive diagnosis in each patient. Complications included subacute acceleration in pulmonary infiltration in one patient. No patient complained of pain or discomfort at the 2 mm-thoraco port sites. Healing of this port site resulted in excellent cosmesis. Mini-videoscopic surgery supported by standard thoracoscopic equipment can be used to perform lung or pleural biopsy less invasively than standard thoracoscopic approach.

[Human heparanase: roles in invasion and metastasis of cancer]

Heparanase, which is an extracellular matrix degradative enzyme, degrades heparan sulfate and heparan sulfate proteoglycans, which are chief components of extracellular matrix and vascular basement membrane. The gene structure of this enzyme was recently determined. The biological functions of this enzyme in vivo were as follows: 1) this enzyme accelerates cancer cell invasion and metastasis though the degradation of vascular basement membrane and extracellular matrix by cancer cells; 2) this enzyme releases and activates heparin-binding growth factors such as bFGF and VEGF from heparan sulfate proteoglycans, and induces angiogenesis; 3) the degradative products of heparan sulfate proteoglycans by this enzyme suppress the biological function of activated T-lymphocytes. Therefore, heparanase is thought to be a favorable molecule for acceleration of cancer invasion and metastasis. The expression of heparanase is strongly correlated with the metastasis of melanoma and fibrosarcoma. Thus, heparanase may play important roles in invasion and metastasis of cancer.

Genomic organization and chromosome localization of the newly identified human heparanase gene

Heparanase (HPSE), which we have recently isolated, is an endo-beta-D-glucuronidase capable of cleaving heparan sulfate and has been implicated in inflammation and tumor angiogenesis and metastasis. In this report, the genomic organization and chromosome localization of the human heparanase gene is described. Polymerase chain reaction, subcloning and DNA sequencing analysis of a bacterial artificial chromosome (BAC) clone revealed that the 3.7 kb human heparanase cDNA is spread over about 50 kb and contains 14 exons and 13 introns. The heparanase gene is expressed as two mRNA species containing the same open reading frame, HPSE 1a (5 kb) (GenBank Data Library under accession number: AF155510); and HPSE 1b (1.7 kb) (GenBank Data Library under accession number: AF144325), generated by alternative splicing. The HPSE 1a-form contains all 14 exons, whereas in the HPSE 1b-form the first and fourteenth exons (5'- and 3'-untranslated region) have been spliced out. All splice sites conform to the GT-AG rule, except for the splice donor site of intron 13 (which is GA instead of GT), and the splice acceptor of intron 13 (which is GG instead of AG). Fluorescence in situ hybridization and radiation hybrid mapping suggest that the heparanase gene is located on human chromosome 4q22. This report regarding the structure of the human heparanase gene will aid in understanding the genetic contribution of this gene to normal physiology as well as to disease states. A possible involvement of heparanase in neuronal degeneration is discussed.

Antigen uptake and subsequent cell kinetics in bronchus-associated lymphoid tissue

OBJECTIVE

Bronchus-associated lymphoid tissue (BALT) plays an important role in the immunological defence of airways. However, the mechanisms of BALT development, antigen sampling, and subsequent cell kinetics remain unclear. To clarify these chronological processes, we used a Pseudomonas aeruginosa-exposed mouse model.

METHODOLOGY

In BALB/c and C57BL/6 mice, BALT development was induced by inhalation of heat-killed P. aeruginosa after sensitization with subcutaneous injection of P. aeruginosa in the presence of Freund's complete adjuvant. Subsequently, we chronologically killed these mice who had inhaled PKH26-labelled P. aeruginosa and examined bacterial transport using fluorescence microscopy. The distribution of interleukin-4-positive cells and interferon-gamma-positive cells was studied immunohistochemically.

RESULTS

The degree of BALT hyperplasia was greater in sensitized mice than in non-sensitized mice and in BALB/c mice than in C57BL/6 mice. PKH26-labelled bacteria were found in BALT earlier in sensitized mice than in non-sensitized mice. Immunohistochemical studies revealed that interleukin-4-positive cells predominated over interferon-gamma-positive cells in the peripheral areas of lymphoid follicles.

CONCLUSION

These results indicate that administered antigens are actively transported into BALT and that sensitized Th2 lymphocytes play an important role in forming and maintaining BALT.

Effects of time averaging on optical scintillation in a ground-to-satellite atmospheric propagation

Temporal natures for a variance of turbulence-induced log-intensity fluctuations are obtained. The variance of the optical fluctuation is reduced when the optical signals are integrated in a photodetector, and we express the index of reduction (called the time-averaging factor) by using an autocovariance function of the optical fluctuation. The optical fluctuations for a ground-to-satellite path are caused by both atmospheric turbulence and the beam-pointing jitter error of the optical transmitter. The turbulence-induced optical scintillation can be discriminated from the fluctuation that is due to the beam-pointing jitter error. The compared result from the probability density function of the optical signal reveals good agreement. The temporal autocovariance functions of optical scintillation are obtained and used to calculate the time-averaging factor. The analytically expected effects of time averaging are verified by the experimental results. The estimations contribute to the link budget design for the optical tracking channel through atmospheric turbulence.

Flexible synthesis and biological activity of uronic acid-type gem-diamine 1-N-iminosugars: a new family of glycosidase inhibitors

An efficient and flexible synthetic route to four gem-diamine 1-N-iminosugars of uronic acid-type (D-glucuronic, D-mannuronic, L-iduronic, and L-guluronic acid), a new family of glycosidase inhibitor, from l-galactono-1,4-lactone have been developed in an enantiodivergent fashion through a sequence involving as the key steps (a) the formation of gem-diamine 1-N-iminopyranose ring by the Mitsunobu reaction of an aminal and (b) the introduction of a carboxylic acid group by the Wittig reaction of a ketone, hydroboration and oxidation, and the Sharpless oxidation. D-Glucuronic and D-mannuronic acid-type 1-N-iminosugars, (3S,4R,5R, 6R)- and (3S,4R,5R,6S)-4, 5-dihydroxy-6-trifluoroacetamido-3-piperidinecarboxylic acid, were proven to be potent inhibitors for beta-D-glucuronidase (IC(50) 6.5 x 10(-)(8)M) and to affect human heparanase (endo-beta-glucuronidase).

[Testicular sarcoidosis]

We report a rare case of testicular sarcoidosis. A 68-year-old man was admitted for detailed examination of uveitis and swelling of the testes. A chest X-ray film and computed tomographic scans disclosed ground-glass shadows in the lower fields of both lungs with mediastinal lymphadenopathy. Ga scintigram showed pronounced accumulations in the testes, hilum, and mediastinum. Transbronchial lung and testicular biopsy specimens demonstrated noncaseating epithelioid granulomas, thus confirming the diagnosis of sarcoidosis with testicular involvement. The patient was followed up without systemic steroids. A review of the world literature found only 12 reported cases of clinically evident testicular sarcoidosis.

Biased T cell receptor Vbeta gene expression in bronchoalveolar lavage fluid from Japanese patients with sarcoidosis

OBJECTIVE

Sarcoidosis is believed to be one of the T cell-mediated granulomatous diseases with unknown aetiology. We attempt to search for the causative T cell clones of sarcoidosis.

METHODS

We study T cell receptor beta-chain variable region (Vbeta) repertoire in peripheral blood (PB) and bronchoalveolar lavage fluid (BALF) from patients with sarcoidosis, using semi-quantitative reverse transcriptase-polymerase chain reaction method. The expression of 22 kinds of Vbeta genes is examined in 17 patients with sarcoidosis and nine normal subjects.

RESULTS

Compared with control subjects, the group with sarcoidosis exhibits significantly high expressions of the Vbeta2 (P < 0.005, Wilcoxon's test) and Vbeta6 (P = 0.005) genes in BALF. In each BALF sample, the Vbeta2 (P < 0.01, chi2 test) and Vbeta6 (P < 0.01) genes were overexpressed (> 2 SD above the mean value for each Vbeta observed in control subjects) in 11 and 10 of 17 patients with sarcoidosis, respectively. Furthermore, the amino acid sequences of Vbeta6+ complementarity determining region 3 were conserved in one of three patients. There is, however, no disposition of Vbeta gene usage in PB from patients with sarcoidosis compared with control subjects.

CONCLUSIONS

The T lymphocytes with Vbeta2 and/or Vbeta6 are associated with the pathogenesis of sarcoidosis. The possibility exists that these T lymphocytes might be capable of recognizing the restricted antigens, thereby inducing oligoclonal expansion.

Somatic cell mutation induced by sunlight in Drosophila

There is ample epidemiological evidence showing that sunlight can cause skin cancer in the human. In experimental studies, simulated sunlight or UV lamps are used for demonstrating carcinogenesis and other biological effects. Little studies, however, have been performed using natural sunlight itself. In this work, we have examined the mutagenicity of natural sunlight in Drosophila. The Drosophila wing spot test is useful to detect somatic cell mutations. Third instar larvae in petri dishes were exposed to sunlight (ultraviolet region with < 290 nm wavelength cut off by a plastic cover) in the yard of Okayama University campus (north latitude: 34 degrees 39', east longitude: 133 degrees 55'). The sunlight was mutagenic in Drosophila larvae and produced pyrimidine dimers in their DNA. In the observed mutagenicity, there was dependence on the exposure period and UV fluence. During the two-year monitoring, the highest induction of mutant spot observed was 1.98 total spots/wing on June 25, 1998, and the lowest was 0.64 on December 29, 1998, while non-exposure spontaneous spots were 0.29 and 0.32 on these days, respectively. Thus, solar radiation was mutagenic both in summer and in winter.