Liquid Structure of Tantalum under Internal Negative Pressure

In situ femtosecond x-ray diffraction measurements and ab initio molecular dynamics simulations were performed to study the liquid structure of tantalum shock released from several hundred gigapascals (GPa) on the nanosecond timescale. The results show that the internal negative pressure applied to the liquid tantalum reached -5.6 (0.8)  GPa, suggesting the existence of a liquid-gas mixing state due to cavitation. This is the first direct evidence to prove the classical nucleation theory which predicts that liquids with high surface tension can support GPa regime tensile stress.

Protein tyrosine phosphatase receptor type Q in cerebrospinal fluid reflects ependymal cell dysfunction and is a potential biomarker for adult chronic hydrocephalus

BACKGROUND AND PURPOSE

Protein tyrosine phosphatase receptor type Q (PTPRQ) was extracted from the cerebrospinal fluid (CSF) of patients with probable idiopathic normal-pressure hydrocephalus (iNPH) by proteome analysis. We aimed to assess the feasibility of using CSF PTPRQ concentrations for the additional diagnostic criterion of iNPH in Japanese and Finnish populations.

METHODS

We compared PTPRQ concentrations among patients with probable iNPH and neurologically healthy individuals (normal control [NC] group), patients with normal-pressure hydrocephalus (NPH) of acquired and congenital/developmental aetiologies, patients with Alzheimer's disease and patients with Parkinson's disease in a Japanese analysis cohort. A corresponding iNPH group and NC group in a Finnish cohort was used for validation. Patients in the Finnish cohort who underwent biopsy were classified into two groups based on amyloid and/or tau deposition. We measured PTPRQ expression levels in autopsied brain specimens of iNPH patients and the NC group.

RESULTS

Cerebrospinal fluid PTPRQ concentrations in the patients with NPH of idiopathic, acquired and congenital/developmental aetiologies were significantly higher than those in the NC group and those with Parkinson's disease, but iNPH showed no significant differences when compared with those in the Alzheimer's disease group. For the patients with iNPH, the area under the receiver-operating characteristic curve was 0.860 in the Japanese iNPH and 0.849 in the Finnish iNPH cohorts. Immunostaining and in situ hybridization revealed PTPRQ expression in the ependymal cells and choroid plexus. It is highly possible that the elevated PTPRQ levels in the CSF are related to ependymal dysfunction from ventricular expansion.

CONCLUSIONS

Cerebrospinal fluid PTPRQ levels indicated the validity of this assay for auxiliary diagnosis of adult chronic hydrocephalus.

Coherent X-ray beam metrology using 2D high-resolution Fresnel-diffraction analysis

Direct metrology of coherent short-wavelength beamlines is important for obtaining operational beam characteristics at the experimental site. However, since beam-time limitation imposes fast metrology procedures, a multi-parametric metrology from as low as a single shot is desirable. Here a two-dimensional (2D) procedure based on high-resolution Fresnel diffraction analysis is discussed and applied, which allowed an efficient and detailed beamline characterization at the SACLA XFEL. So far, the potential of Fresnel diffraction for beamline metrology has not been fully exploited because its high-frequency fringes could be only partly resolved with ordinary pixel-limited detectors. Using the high-spatial-frequency imaging capability of an irradiated LiF crystal, 2D information of the coherence degree, beam divergence and beam quality factor M² were retrieved from simple diffraction patterns. The developed beam metrology was validated with a laboratory reference laser, and then successfully applied at a beamline facility, in agreement with the source specifications.

Generation of pressures over 40 GPa using Kawai-type multi-anvil press with tungsten carbide anvils

We have generated over 40 GPa pressures, namely, 43 and 44 GPa, at ambient temperature and 2000 K, respectively, using Kawai-type multi-anvil presses (KMAP) with tungsten carbide anvils for the first time. These high-pressure generations were achieved by combining the following pressure-generation techniques: (1) precisely aligned guide block systems, (2) high hardness of tungsten carbide, (3) tapering of second-stage anvil faces, (4) materials with high bulk modulus in a high-pressure cell, and (5) high heating efficiency.

Laser-shock compression of magnesium oxide in the warm-dense-matter regime

Magnesium oxide has been experimentally and computationally investigated in the warm-dense solid and liquid ranges from 200 GPa to 1 TPa along the principal Hugoniot. The linear approximation between shock velocity and particle velocity is validated up to a shock velocity of 15 km/s from the experimental data, this suggesting that the MgO B1 structure is stable up to the corresponding shock pressure of ∼350 GPa. Moreover, our Hugoniot data, combined with ab initio simulations, show two crossovers between MgO Hugoniot and the extrapolation of the linear approximation line, occurring at a shock pressures of approximately 350 and 650 GPa, with shock temperatures of 8000 and 14,000 K, respectively. These crossover regions are consistent with the solid-solid (B1-B2) and the solid-liquid (B2-melt) phase boundaries predicted by the ab initio calculations.

Two-hybrid search for proteins that interact with Sad1 and Kms1, two membrane-bound components of the spindle pole body in fission yeast

In interphase cells of fission yeast, the spindle pole body (SPB) is thought to be connected with chromosomal centromeres by an as yet unknown mechanism that spans the nuclear membrane. To elucidate this mechanism, we performed two-hybrid screens for proteins that interact with Kms1 and Sad1, which are constitutive membrane-bound components of the SPB that interact with each other. Seven and 26 genes were identified whose products potentially interact with Kms1 and Sad1, respectively. With the exception of Dlc1 (a homolog of the 14-kDa dynein light chain), all of the Kms1 interactors also interacted with Sad1. Among the genes identified were the previously known genes rhp9+ / crb2+, cut6+, ags1+ / mok1+, gst3+, kms2+, and sid4+. The products of kms2+ and sid4+ localize to the SPB. The novel genes were characterized by constructing disruption mutations and by localization of the gene products. Two of them, putative homologues of budding yeast UFE1 (which encodes a t-SNARE) and SFH1 (an essential component of a chromatin-remodeling complex), were essential for viability. Two further genes, which were only conditionally essential, genetically interact with sad1+. One of these was named sif1+ (for Sad1-interacting factor) and is required for proper septum formation at high temperature. Cells in which this gene was overexpressed displayed a wee -like phenotype. The product of the other gene, apm1+, is very similar to the medium chain of an adaptor protein complex in clathrin-coated vesicles. Apm1 appears to be required for SPB separation and spindle formation, and tended to accumulate at the SPB when it was overproduced. It was functionally distinct from its homologues Apm2 and Apm4. Other novel genes identified in this study included one for a nucleoporin and genes encoding novel membrane-bound proteins that were genetically related to Sad1. We found that none of the newly identified genes tested were necessary for centromere/telomere clustering.

Treatment of a scalp arteriovenous malformation by a combination of embolization and surgical removal

SUMMARY

The authors describe a 21-year-old man in whom a large arteriovenous malformation of the scalp was eliminated using a combined interventional, neuroradiological and neurosurgical approach. Embolization was utilized to reduce arterial blood supply to the malformation. Eudragit- E, as a liquid embolic material from a cationic polymer, methyl and butyl methacrylate, and dimethylaminoethyl methacrylate copolymer, was injected through the transarterial route and then by direct percutaneous puncture of the nidus. One week after embolization, the nidus was easily resected with minimal blood loss. A postoperative angiogram showed nearly total extirpation of the nidus as well as complete clinical recovery. Preoperative embolization in this case was a safe and effective ablative technique.

Transcondylar fossa approach to treat ventral foramen magnum meningioma--case report

A 41-year-old female presented with a meningioma of the craniocervical junction manifesting as tetraparesis and vesicourethral dysfunction. Neuroradiological examinations showed a homogeneous enhanced mass lesion extending from the foramen magnum to the upper aspect of the second vertebral body. The tumor was totally removed via the transcondylar fossa approach, which is one type of the lateral approach. She was discharged without neurological deficits. The transcondylar approach is often utilized for lesions that occupy the ventral portion around the foramen magnum. The transcondylar fossa approach, a variation of the transcondylar approach, is a refined technique which obtains a closely similar surgical working field. Use of the transcondylar fossa approach remains controversial when treating patients with little brain stem dislocation, a small condylar fossa, and a protruding occipital condyle, but the approach can easily be converted to the transcondylar approach. The transcondylar fossa approach could become a standard method to access the craniocervical junction.

Interhemispheric glioependymal cyst associated with agenesis of the corpus callosum--case report

A male neonate was admitted because prenatal ultrasonography indicated central nervous system abnormalities. Neurological examination showed no abnormality except for electroencephalographic spike activities. Magnetic resonance imaging revealed a cystic lesion in the left interhemispheric fissure, agenesis of the corpus callosum, and microgyria in the left frontotemporal lobes. Cerebral blood flow (CBF) was diffusely reduced. The cyst wall was partially removed and a cyst-peritoneal shunt procedure was performed. The histological diagnosis was glioependymal cyst. The spike activity disappeared and CBF dramatically improved after the operation.

[A case of subarachnoid hemorrhage verified as cerebral vasospasm by using three-dimensional CT angiography (3 D-CTA): reference to comparison with conventional angiography]

The authors present a case of aneurysmal subarachnoid hemorrhage that were verified as cerebral vasospasm by using both three-dimensional CT angioraphy (3 D-CTA) and conventional angiography. A 45-year-old man was referred to our department 4th day after sudden onset of a severe headache. On admission, emergency 3 D-CTA showed the cerebral vasospasm involving M 1 segment. Conventional angiography performed at the same day of the left internal carotid artery confirmed the cerebral vasospasm of the same vessel as 3 D-CTA, and furthermore demonstrated the left middle cerebral artery (MCA) and anterior cerebral artery (ACA) genu aneurysms. The former was seen as a ruptured aneurysm from brain CT findings (Fisher group 3). On the 10th day after the onset, 3 D-CTA demonstrated the remaining severe cerebral vasospasm of the supraclinoid portion of left ICA and M 1 segment. Findings at the conventional angiography subsequently performed were concordant with those of 3 D-CTA. The patient was successfully treated with delayed surgical clipping for both aneurysms without the symptoms related to the cerebral vasospasm and discharged without neurological abnormality. We consider that 3 D-CTA shows promise as a minimally invasive method of evaluating the cerebral vasospasm and would take the place of the conventional angiography.

A novel fission yeast gene, tht1+, is required for the fusion of nuclear envelopes during karyogamy

We have isolated a fission yeast karyogamy mutant, tht1, in which nuclear congression and the association of two spindle pole bodies occurs but the subsequent fusion of nuclear envelopes is blocked. The tht1 mutation does not prevent meiosis, so cells execute meiosis with two unfused nuclei, leading to the production of aberrant asci. The tht1(+) gene was cloned and sequenced. Predicted amino acid sequence has no significant homology to previously known proteins but strongly suggests that it is a type I membrane protein. The tht1(+) gene is dispensable for vegetative growth and expressed only in conjugating cells. Tht1p is a glycoprotein susceptible to endoglycosilase H digestion. Site- directed mutagenesis showed that the N-glycosylation site, as well as the COOH-terminal region of Tht1p, is essential for its function. A protease protection assay indicated that the COOH terminus is cytoplasmic. Immunocytological analysis using a HA-tagged Tht1p suggested that the protein is localized in nuclear envelopes and in the ER during karyogamy and that its levels are reduced in cells containing fused nuclei.

Non-X-linked hyper-IgM syndrome with systemic lupus erythematosus

A 24-year-old woman had suffered from recurrent bacterial infections and clinical manifestations of systemic lupus erythematosus (SLE). Laboratory findings disclosed an elevated level of serum IgM, markedly decreased IgG, IgA, IgD and IgE levels, and low levels of serum complement. Both the CD40 and CD40 ligands appeared to be normally expressed. Assays of in vitro immunoglobulin production by lymphocytes showed that IgM was produced normally and that IgE but not IgG or IgA production was rescued by signaling through CD40 on B cells. The proliferative response of lymphocytes to phobol ester was markedly decreased, suggesting some impairment of signal transduction in the patient's lymphocytes.

Identification of the ure1+ gene encoding urease in fission yeast

Cloning and sequencing of the ure1+ gene of Schizosaccharomyces pombe indicated that it encodes the urease which had been biochemically identified. The fission yeast urease has a one-subunit structure like those from plants but different from bacterial ureases which are composed of two or three distinct subunits. Genetic analyses showed that the ure1+ gene product is actually involved in urea metabolism.

SFA-2, a novel bZIP transcription factor induced by human T-cell leukemia virus type I, is highly expressed in mature lymphocytes

A novel cellular gene, SFA-2, was isolated by differential hybridization of a cDNA library, using probes obtained from an adult T-cell leukemia cell line in comparison with normal CD4+ T cells and MOLT-4 cell line. The mRNA of the SFA-2 gene is approximately 0.9-kb in size and encodes a protein of 125 amino acids, containing a basic region-leucine zipper DNA-binding domain. The N-terminal region of SFA-2 is rich in serine and contains a consensus sequence for casein kinase II phosphorylation. The SFA-2 gene was strongly expressed in mature T and B lymphocytes, and was up-regulated after transformation by human T-cell leukemia virus type I. The SFA-2 did not homodimerize efficiently but formed heterodimer preferentially with c-Jun. The SFA-2/c-Jun heterodimer bound preferentially to the AP-1 and CRE sites.

Deletion in the 190 kDa antigen gene repeat region of Rickettsia rickettsii

The 190 kDa outer membrane protein of Rickettsia rickettsii is a major immunodominant protective antigen which contains 13 tandem nearly identical repeating sequences. We have identified a deletion in the 190 kDa antigen gene of R. rickettsii strain Smith maintained in the laboratory. The deletion occurred within the repeat region of this gene and the mutated repeat region corresponded to one repeating unit in size.

A selection system for diploid and against haploid cells in Schizosaccharomyces pombe

We have isolated a mutant of Schizosaccharomyces pombe whose growth is temperature sensitive when it is haploid but not when it is diploid. This mutant may provide a useful system for selecting nonconditional mutants which are defective in diploid formation upon conjugation.

[A case of tsutsugamushi disease which occurred in south western Shikoku]

We report a case of tsutsugamushi disease found in south western Shikoku. A 64-year-old male who lived in Towa Village in Kochi, developed a fever and headache on April 6, 1994, and was admitted to Uwajima City Hospital on April 15, with a ten-day history of illness. He had an eschar on the right anterior side of the breast and an enlargement of the right axillary lymph node, without a rash. Laboratory data showed mild liver injury and atypical lymphocytes with 6% in peripheral blood. After his blood was drawn for rickettsial isolation, the minocycline was administered. His symptoms improved rapidly and was discharged in good condition. We successfully isolated the causative agent, Rickettsia tsutugamushi, and designated it as the Shiba strain. High antibody titer against the Kato, Karp and Gilliam strains was detected in serum on admission and increased during the course of the disease. In Shikoku, tsutsugamushi disease is rare and only 13 cases were reported during last ten years. Especially in south western district of Shikoku, there have been no case reported since 1960. This case is important epidemiologically and suggests that we should pay attention to this disease.

Detection of DNA of causative agent of spotted fever group rickettsiosis in Japan from the patient's blood sample by polymerase chain reaction

The polymerase chain reaction (PCR) was applied for the etiological diagnosis of spotted fever group (SFG) rickettsiosis in Japan. Nucleotide primers derived from the 17-kDa antigen gene of Rickettsia rickettsii primed a rickettsia-specific 246-base-pair product for all of the Katayama, Abe, Misaka and Kojima strains, which we had isolated previously. Moreover, we were able to detect the same product by PCR amplification from the peripheral blood of a patient in the acute stage of the illness. The PCR method is considered to be useful for rapid etiological diagnosis of SFG rickettsiosis in Japan.

Autooxidation of alkylhydrazones and mutagenicity of the resulting hydroperoxides

Acetone alkylhydrazones were readily autooxidized to 2-alkylazo-2-propyl hydroperoxides, which were directly mutagenic in Salmonella typhimurium TA1535, TA100, TA102 and Escherichia coli WP2hcr. The mechanism of this mutagenicity presumes that the hydroperoxides in aqueous solution decompose to alkyl diazonium ions which were observed in the alkylation of 4-(p-nitrobenzyl)pyridine, and also to hydroxyl radical which was detected by ESR.

[Characterization of Rickettsia tsutsugamushi strains newly isolated in Ehime Prefecture, Japan]

Five strains of Rickettsia tsutsugamushi were isolated in Ehime Prefecture during December 1987 to January 1990. Of these, two strains, the Yamazaki and Noma-3, were isolated at Noma area of Imabari city and three strains, the Kakiwara-10, -11, -12, at Kakiwara area of Uwajima city. The Yamazaki strain was isolated from a patient of tsutsugamushi disease and the other strains from wild rodents (Apodemus speciosus). These strains showed virulence in euthymic mice. The calculated LD50 of the Yamazaki and Kakiwara-10 strains showed 10(-3.0) and 10(-1.8), respectively. The immunofluorescent antibody test using thirty monoclonal antibodies to six representative strains, the Gilliam, Karp, Kato, Irie, Hirano and Shimokoshi, revealed that two strains isolated at Noma area, the Yamazaki and Noma-3, were identified as the Karp type and three strains at Kakiwara area, the Kakiwara-10, -11, -12, were identified as the Kato type. It was clarified that the serotypic differences were present among the strains isolated in Ehime Prefecture. Moreover, these five strains isolated in Ehime Prefecture did not react with the serotype-specific monoclonal antibodies to the Irie, Hirano and Shimokoshi strains known as the representative strains of so-called new type of tsutsugamushi disease, showing antigenic differences.

Ultrastructural study of the response of cells infected in vitro with causative agent of spotted fever group rickettsiosis in Japan

The response of host cells L929 infected with causative agent of spotted fever group (SFG) rickettsiosis in Japan, the Katayama strain, was studied by electron microscopy. The rickettsiae penetrated the cytoplasm and multiplied here and after prolonged incubation progressed into the dilated cisternae of rough endoplasmic reticulum (rER), the perinuclear space, the deep invaginated nuclear membrane, and then the nucleoplasm of the host cells. The intranuclear rickettsiae showed different states: one type was enclosed by the double membrane of the host cell and the other type was free in the nucleoplasm. In addition to these double membrane-bound and membrane-free intranuclear rickettsiae, various membrane structures, including rER-like structures, were also found in the nucleus. The cells infected with the rickettsiae underwent distinctive morphological alterations which occurred mainly within intracellular membranes of the host cells. These findings indicate the possibility that the intracellular membranes are characteristic cytopathological sites in rickettsia-host cell interaction, and that these alterations may be related to a possible route of rickettsial penetration into the nucleus: passage through vesicles formed from invaginations in the nuclear membrane.

Analysis of immunological characteristics of newly isolated strains of Rickettsia tsutsugamushi using monoclonal antibodies

Since 1975, there has been an increase in the number of patients with tsutsugamushi disease in Japan, and marked antigenic heterogeneity has been found among newly isolated strains of Rickettsia tsutsugamushi. For antigenic analysis of these strains, we produced monoclonal antibodies against the Irie strain isolated in 1971, and the Hirano and Shimokoshi strains isolated in 1980. In all, 34 monoclonal antibodies were produced and their reactivities were determined by the immunofluorescent antibody test. The serological reactivity of the antibodies against these three strains and classic representative strains (Gilliam, Karp and Kato) showed varied reactive characteristics, i.e., serotype-specific, species-specific and intermediate reactivities. It was revealed that these strains are antigenically different from the classic ones. Moreover, by using the serotype-specific monoclonal antibodies, nine strains newly isolated in Miyazaki Prefecture were classified into the Irie and the Hirano types. The antigenicity of the Shimokoshi strain differed from those of the other strains used in this study. From these results, the strains of R. tsutsugamushi used in this study fell into six serotypes including the classic strains. SDS-PAGE and immunoblotting were performed to determine the molecular sizes of the antigenic polypeptides. The results revealed that the serotype-specific antigens belong to the 60-kDa class whereas the species-specific antigens belong to the 61-kDa, 60-kDa or 44-kDa class.

Causative agent of spotted fever group rickettsiosis in Japan

Since 1984, it has been known that spotted fever group rickettsiosis exists in Japan. We isolated three strains of the causative rickettsiae, designated Katayama, Misaka, and Abe, from patients with the disease and studied the characteristics of the isolates. Nude mice and cyclophosphamide-treated mice died after infection with the isolates. However, infected normal mice recovered and acquired immunity. Infected adult male guinea pigs had fever, a scrotal reaction, and seroconversion. The isolates propagated well in tissue-cultured Vero cells. Analysis by the cross-immunofluorescence antibody method showed that these isolates were closely related serologically. To reveal their immunological properties in detail, we produced 21 anti-Katayama monoclonal antibodies. Seven of these antibodies reacted with all representative strains of spotted fever group rickettsiae used in this study, and five others reacted only with the homologous strain, revealing that the Katayama strain has a strain-specific antigen(s) different from those of other spotted fever group rickettsiae. Moreover, these strain-specific antibodies also reacted with the Misaka and Abe strains. These results demonstrate that the causative agent of spotted fever group rickettsiosis in Japan is a new serotype of spotted fever group rickettsiae.

[The causative agent from a patient with spotted fever group rickettsiosis in Japan on Awaji Island, Hyogo]

Misaka strain was isolated as the causative agent from a patient with spotted fever group rickettsiosis in Japan by using nude mice on Awaji Island, Hyogo in September 1988. The nude mice infected with the isolate showed weakness and splenomegaly and died in two or three weeks after the infection. The cyclophosphamide-treated mice infected with the isolate died between four and seven days after the infection. The infected normal mice recovered and acquired immunity. The infected adult male guinea pigs were feverish and showed swelling and redness of the scrotum between two and eight days after the infection, and recovered. The Misaka strain was propagated well in Vero cells in tissue culture. The rickettsial particles were seen as diplobacillary and diplococcal forms growing predominantly in the cytoplasm and occasionally in the nucleus of infected cells. The serological characteristics of the Misaka strain were analyzed by the cross-immunofluorescent antibody method. The Misaka strain, the Katayama strain first isolated in Tokushima in 1987, and the representative strains of spotted fever group rickettsiae in the world; R. rickettsii Smith, R. sibirica 246, R. conorii Moroccan, R. akari MK (Kaplan), R. australis Phillips, R. montana Tick and Thai TT-118 strains were used as antigens. And immune mouse serum samples against the Misaka, Katayama, 246, Phillips and TT-118 strains were used as antisera. The result revealed that these strains showed cross-reaction and share a common antigen of spotted fever group rickettsiae. Furthermore, it became obvious that the Misaka strain and the Katayama strain have the same serotype-specific antigen different from the strains of other spotted fever group rickettsiae using Anti-Katayama monoclonal antibodies.

[The first case of tsutsugamushi disease in Ehime Prefecture]

The first case of tsutsugamushi disease in Ehime Prefecture was experienced in December 1987 with successful isolation of the causative agent. The patient was taken ill twelve days after infection. Immunofluorescent antibody tests using the isolate, Yamazaki strain, and Gilliam, Karp, Kato, Irie and Shimokoshi strains as antigens revealed that the specific antibodies against these antigens appeared and increased in the blood of the patient during the course of the disease. And the antibody titers to the Yamazaki antigen were the highest of these antigens. Agglutinin for Proteus OXK did not appear in the blood of the patient. The immunofluorescent antibody test using type-specific monoclonal antibodies to Gilliam, Karp, Kato, Irie and Shimokoshi strains and these five strains and the Yamazaki strain as antigens revealed that the Yamazaki strain was identified as Karp type of Rickettsia tsutsugamushi.