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1.
NMC Case Rep J ; 10: 327-330, 2023.
Article in English | MEDLINE | ID: mdl-38125932

ABSTRACT

We report a patient with idiopathic intracranial hypertension (IIH) with bilateral transverse sinus occlusion treated by a lumboperitoneal shunt. A 45-year-old woman presented with visual disturbance and chronic headache. Magnetic resonance (MR) venography and three-dimensional computed tomography angiography (3D-CTA) showed occlusion of both transverse sinuses. After the surgery, MR venography and 3D-CTA showed no blockages in both transverse sinuses. This phenomenon reveals that obstruction of the bilateral transverse sinus is a consequence of intracranial hypertension, not just a single cause. Since many patients have an obstruction or stenosis of the venous sinus, there are some reports of endovascular treatment. Sinus reconstruction is usually effective, but it is not effective in some cases. Reversal of sinus occlusion suggests that endovascular therapy for IIH is inadequate in some cases.

2.
Life (Basel) ; 13(5)2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37240748

ABSTRACT

Life most likely started during the Hadean Eon; however, the environmental conditions which contributed to the complexity of its chemistry are poorly known. A better understanding of various environmental conditions, including global (heliospheric) and local (atmospheric, surface, and oceanic), along with the internal dynamic conditions of the early Earth, are required to understand the onset of abiogenesis. Herein, we examine the contributions of galactic cosmic rays (GCRs) and solar energetic particles (SEPs) associated with superflares from the young Sun to the formation of amino acids and carboxylic acids in weakly reduced gas mixtures representing the early Earth's atmosphere. We also compare the products with those introduced by lightning events and solar ultraviolet light (UV). In a series of laboratory experiments, we detected and characterized the formation of amino acids and carboxylic acids via proton irradiation of a mixture of carbon dioxide, methane, nitrogen, and water in various mixing ratios. These experiments show the detection of amino acids after acid hydrolysis when 0.5% (v/v) of initial methane was introduced to the gas mixture. In the set of experiments with spark discharges (simulation of lightning flashes) performed for the same gas mixture, we found that at least 15% methane was required to detect the formation of amino acids, and no amino acids were detected in experiments via UV irradiation, even when 50% methane was used. Carboxylic acids were formed in non-reducing gas mixtures (0% methane) by proton irradiation and spark discharges. Hence, we suggest that GCRs and SEP events from the young Sun represent the most effective energy sources for the prebiotic formation of biologically important organic compounds from weakly reducing atmospheres. Since the energy flux of space weather, which generated frequent SEPs from the young Sun in the first 600 million years after the birth of the solar system, was expected to be much greater than that of GCRs, we conclude that SEP-driven energetic protons are the most promising energy sources for the prebiotic production of bioorganic compounds in the atmosphere of the Hadean Earth.

3.
Neuropathology ; 42(6): 512-518, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36071620

ABSTRACT

Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare glioneuronal neoplasm newly included in the 2016 World Health Organization Classification of Tumors of the Central Nervous System. Owing to the wide spectrum of its histopathological and radiological features, accurate diagnosis can be challenging. Recently, molecular testing including DNA methylation array has been introduced with the possibility of improving diagnostic accuracy and contributing to the subtyping especially for brain tumors with ambiguous histology. Two molecularly distinct subtypes of DLGNT have been reported: methylation class-1 (MC-1) with an indolent clinical course and MC-2, the latter aggressive. Herein, we report a case of a 14-year-old girl with a conspicuous hypothalamic mass lesion and diffuse leptomeningeal enhancement on magnetic resonance imaging. Biopsy specimens obtained from the hypothalamic lesion endoscopically were mainly composed of oligodendrocyte-like cells. However, it was difficult to make a definite diagnosis from these non-specific histological findings. Thus, DNA methylation array analysis was performed additionally by using formalin-fixed, paraffin-embedded tissue, resulting in a diagnosis of "MC-1 subtype of DLGNT" with a high calibrated score (0.99). Consequently, she was treated conservatively, with neither progression of the tumor nor aggravation of symptoms for the next 12 months. It was concluded that DNA methylation array analysis for DLGNT, a rare glioneuronal tumor, could be a powerful tool not only for accurate diagnosis but also decision-making in selecting the best treatment.


Subject(s)
Brain Neoplasms , Central Nervous System Neoplasms , Meningeal Neoplasms , Neoplasms, Neuroepithelial , Female , Humans , Meningeal Neoplasms/diagnostic imaging , Meningeal Neoplasms/genetics , Meningeal Neoplasms/pathology , DNA Methylation , Neoplasms, Neuroepithelial/pathology , Central Nervous System Neoplasms/pathology , Brain Neoplasms/pathology
4.
Front Microbiol ; 11: 2050, 2020.
Article in English | MEDLINE | ID: mdl-32983036

ABSTRACT

The hypothesis called "panspermia" proposes an interplanetary transfer of life. Experiments have exposed extremophilic organisms to outer space to test microbe survivability and the panspermia hypothesis. Microbes inside shielding material with sufficient thickness to protect them from UV-irradiation can survive in space. This process has been called "lithopanspermia," meaning rocky panspermia. We previously proposed sub-millimeter cell pellets (aggregates) could survive in the harsh space environment based on an on-ground laboratory experiment. To test our hypothesis, we placed dried cell pellets of the radioresistant bacteria Deinococcus spp. in aluminum plate wells in exposure panels attached to the outside of the International Space Station (ISS). We exposed microbial cell pellets with different thickness to space environments. The results indicated the importance of the aggregated form of cells for surviving in harsh space environment. We also analyzed the samples exposed to space from 1 to 3 years. The experimental design enabled us to get and extrapolate the survival time course to predict the survival time of Deinococcus radiodurans. Dried deinococcal cell pellets of 500 µm thickness were alive after 3 years of space exposure and repaired DNA damage at cultivation. Thus, cell pellets 1 mm in diameter have sufficient protection from UV and are estimated to endure the space environment for 2-8 years, extrapolating the survival curve and considering the illumination efficiency of the space experiment. Comparison of the survival of different DNA repair-deficient mutants suggested that cell aggregates exposed in space for 3 years suffered DNA damage, which is most efficiently repaired by the uvrA gene and uvdE gene products, which are responsible for nucleotide excision repair and UV-damage excision repair. Collectively, these results support the possibility of microbial cell aggregates (pellets) as an ark for interplanetary transfer of microbes within several years.

5.
Mar Pollut Bull ; 145: 649-655, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31590834

ABSTRACT

With the use of an in situ and static method for gamma-ray measurements, levels of radioactive cesium 137 on shallow rugged reefs which lie between 37.3° N and 37.4° N, from the coastline of Fukushima to 141.06° E, at a depth of around 10 m were surveyed for the first time from May 2016 to December 2017. To confirm the contact between the detector and a surface of rock, we used a fact that potassium containing minerals are abundant and uniformly distributed in the area, and thus the strength of the photoelectric peak of natural radioactive potassium 40 is nearly constant over the area. We have found that the levels of radioactive cesium 137 varied from point to point within a range from 1 × 104 Bq/m2 to 6 × 104 Bq/m2.


Subject(s)
Cesium Radioisotopes/analysis , Water Pollutants, Radioactive/analysis , Environmental Monitoring/instrumentation , Environmental Monitoring/methods , Fukushima Nuclear Accident , Japan , Potassium Radioisotopes/analysis , Radiation Monitoring/instrumentation , Radiation Monitoring/methods
8.
Mar Biotechnol (NY) ; 18(1): 144-60, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26593063

ABSTRACT

We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and complementary DNA (cDNA) cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per liter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48 - 1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).


Subject(s)
HIV Envelope Protein gp120/metabolism , HIV/physiology , Mannose-Binding Lectins/administration & dosage , Mannose-Binding Lectins/metabolism , Rhodophyta/metabolism , Virus Internalization/drug effects , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/chemistry , Anti-HIV Agents/metabolism , Binding Sites , HIV/drug effects , Mannose-Binding Lectins/genetics , Protein Binding , Protein Engineering/methods , Recombinant Proteins/administration & dosage , Recombinant Proteins/metabolism , Rhodophyta/genetics
9.
Mar Biotechnol (NY) ; 18(2): 215-31, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26661793

ABSTRACT

We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and cDNA cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per a litter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide-binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48-1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).


Subject(s)
Algal Proteins/pharmacology , Anti-HIV Agents/pharmacology , HIV Envelope Protein gp120/antagonists & inhibitors , HIV-1/drug effects , Lectins/pharmacology , Rhodophyta/chemistry , Virus Internalization/drug effects , Algal Proteins/biosynthesis , Algal Proteins/genetics , Algal Proteins/isolation & purification , Amino Acid Sequence , Anti-HIV Agents/isolation & purification , Anti-HIV Agents/metabolism , Carbohydrate Sequence , Cloning, Molecular , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Expression , HIV Envelope Protein gp120/metabolism , HIV-1/physiology , Humans , Jurkat Cells , Lectins/biosynthesis , Lectins/genetics , Lectins/isolation & purification , Mannose/chemistry , Mannose/metabolism , Oligosaccharides/chemistry , Oligosaccharides/metabolism , Protein Binding , Protein Isoforms/biosynthesis , Protein Isoforms/genetics , Protein Isoforms/isolation & purification , Protein Isoforms/pharmacology , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/pharmacology , Sequence Alignment
10.
Biol Pharm Bull ; 33(12): 1971-6, 2010.
Article in English | MEDLINE | ID: mdl-21139235

ABSTRACT

Cardiac structural and functional abnormalities are observed in metabolic syndrome. However, such changes have not been investigated in the SHRSP.Z-Lepr(fa)/IzmDmcr rat (SHRSP-fatty) model of metabolic syndrome. Here we compare cardiac size and hemodynamic function in these rats with their lean littermates (SHRSP) and normotensive control Wistar-Kyoto rats (WKY). In male 16-week-old SHRSP-fatty, we determined heart rate and systolic blood pressure (SBP) by tail-cuff, cardiac output (CO), subcutaneous peripheral blood flow (BF) and stroke volume (SV) by plethysmography, and systolic and diastolic functions by echocardiography. We also assessed weight and collagen type I expression by Western blot in isolated atrium and ventricle, and beat rate in isolated atrial preparation by myography. Heart rate was lower in conscious SHRSP-fatty than SHRSP, and the beat rate of isolated atria was lower in SHRSP-fatty and SHRSP than that of WKY. Atrial weight was larger in SHRSP-fatty than others. Ventricular weight of SHRSP-fatty and SHRSP was larger than WKY. There were significant inverse correlations between atrial weight and heart rate or beat rate in SHRSP-fatty. SBP, CO, BF and SV were increased in SHRSP-fatty similarly to SHRSP. Increased deceleration time and decreased E/A ratio, and preserved fractional shortening were observed in SHRSP-fatty. Expressions of collagen type I were increased in atria and ventricle of SHRSP-fatty. SHRSP-fatty with metabolic syndrome exhibit cardiac changes, including slowed heart rate, ventricular diastolic dysfunction, and fibrosis, and atrial enlargement. SHRSP-fatty may be a useful rat model to study on cardiac abnormalities in metabolic syndrome.


Subject(s)
Collagen Type I/metabolism , Disease Models, Animal , Heart/physiopathology , Metabolic Syndrome , Myocardium/pathology , Animals , Atrial Function/physiology , Fibrosis/metabolism , Heart Rate/physiology , Male , Metabolic Syndrome/pathology , Metabolic Syndrome/physiopathology , Organ Size , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Rats, Zucker , Ventricular Function/physiology
11.
Rev Sci Instrum ; 79(4): 043303, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18447524

ABSTRACT

A cosmic dust detector for use onboard a satellite is currently being developed by using piezoelectric lead zirconate titanate (PZT). The characteristics of the PZT detector have been studied by bombarding it with hypervelocity iron (Fe) particles supplied by a Van de Graaff accelerator. One central electrode and four peripheral electrodes were placed on the front surface of the PZT detector to measure the impact positions of the incident Fe particles. It was demonstrated that the point of impact on the PZT detector could be identified by using information on the time at which the first peak of the output signal obtained from each electrode appeared.

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