Erratum: Using Diffuse Scattering to Observe X-Ray-Driven Nonthermal Melting [Phys. Rev. Lett. 126, 015703 (2021)].

This corrects the article DOI: 10.1103/PhysRevLett.126.015703.

Using Diffuse Scattering to Observe X-Ray-Driven Nonthermal Melting.

We present results from the SPring-8 Angstrom Compact free electron LAser facility, where we used a high intensity (∼10^{20} W/cm^{2}) x-ray pump x-ray probe scheme to observe changes in the ionic structure of silicon induced by x-ray heating of the electrons. By avoiding Laue spots in the scattering signal from a single crystalline sample, we observe a rapid rise in diffuse scattering and a transition to a disordered, liquidlike state with a structure significantly different from liquid silicon. The disordering occurs within 100 fs of irradiation, a timescale that agrees well with first principles simulations, and is faster than that predicted by purely inertial behavior, suggesting that both the phase change and disordered state reached are dominated by Coulomb forces. This method is capable of observing liquid scattering without masking signal from the ambient solid, allowing the liquid structure to be measured throughout and beyond the phase change.

Micron-scale phenomena observed in a turbulent laser-produced plasma.

Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1µm) over a large field of view (>1 mm2). After the evolution of a Rayleigh-Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations.

Molecular karyotyping of human hepatocellular carcinoma using single-nucleotide polymorphism arrays.

Genomic amplification of oncogenes and inactivation of suppressor genes are critical in the pathogenesis of human cancer. To identify chromosomal alterations associated with hepatocarcinogenesis, we performed allelic gene dosage analysis on 36 hepatocellular carcinomas (HCCs). Data from high-density single-nucleotide polymorphism arrays were analysed using the Genome Imbalance Map (GIM) algorithm, which simultaneously detects DNA copy number alterations and loss of heterozygosity (LOH) events. Genome Imbalance Map analysis identified allelic imbalance regions, including uniparental disomy, and predicted the coexistence of a heterozygous population of cancer cells. We observed that gains of 1q, 5p, 5q, 6p, 7q, 8q, 17q and 20q, and LOH of 1p, 4q, 6q, 8p, 10q, 13q, 16p, 16q and 17p were significantly associated with HCC. On 6q24-25, which contains imprinting gene clusters, we observed reduced levels of PLAGL1 expression owing to loss of the unmethylated allele. Finally, we integrated the copy number data with gene expression intensity, and found that genome dosage is correlated with alteration in gene expression. These observations indicated that high-resolution GIM analysis can accurately determine the localizations of genomic regions with allelic imbalance, and when integrated with epigenetic information, a mechanistic basis for inactivation of a tumor suppressor gene in HCC was elucidated.

HeLaTG cells have mitochondrial DNA inserted into the c-myc oncogene.

To determine whether mitochondrial DNA (mtDNA) fragments found within the nucleus are transcribed, we have differentially screened a HeLaTG cDNA library. A clone that hybridized to mtDNA as well as to c-myc was identified. Analysis of the cDNA disclosed that it contained a mtDNA sequence, encoding cytochrome-c oxidase subunit III (coxIII) that was contiguous with and 5' of a c-myc sequence corresponding to part of exon 2 and exon 3. Hybridization of ScaI-digested DNA with a 1.05 kb c-myc probe revealed a unique band in HeLaTG cells, as well as a band common to HeLaTG and 13 other cell types examined. Solution hybridization of HeLaTG RNA with a radiolabeled, single-stranded cDNA probe containing the coxIII-c-myc junction demonstrated a nuclease-resistant band that matched the full length of the junctional cDNA probe. A smaller band that equaled the size of the c-myc portion alone was also detected. Only the smaller band coinciding with the c-myc sequences was protected from nuclease digestion by RNA from other cells. When a radiolabeled probe synthesized in the opposite orientation was used, nuclease-resistant bands equal in length to the coxIII portion of the probe were detected after hybridization with RNA from all cells. These results indicate that insertion of mtDNA fragments into nuclear genes occurs and that subsequent transcription of a 'chimaeric' or 'fusion' mRNA containing both mitochondrial and nuclear sequences can ensue.

Corticotropin-releasing factor modulation of Ca2+ influx in rat pancreatic beta-cells.

The effects of corticotropin-releasing factor (CRF) on the intracellular concentration of Ca2+ were studied in isolated single beta-cells of the rat islet. Immunohistochemical staining using CRF-receptor antibodies revealed the presence of both type 1 (CRF-R1) and type 2 (CRF-R2) receptors for CRF in the majority of islet cells. CRF (2 nmol/l) increased cytosolic Ca2+ concentration under 2.8 mmol/l glucose, dependent upon extracellular Ca2+. CRF caused depolarization of the cell membrane, which was followed by action potentials under 2.8 mmol/l glucose. The dose-response relationships of CRF-induced depolarization in the presence of 1 micromol/l nifedipine produced a bell-shaped curve, showing the peak response at 2 nmol/l. In the whole-cell patch-clamp recording, CRF enhanced Ca2+ currents through L-type Ca2+ channels in a dose-dependent manner similar to that for depolarization. In cells pretreated with Rp-deastereomer of adenosine cyclic 3',5'-phosphorothiolate (100 micromol/l), neither depolarization nor an increase in the Ca2+ current was caused by CRF at concentrations <2 nmol/l. In these cells, CRF at 20 nmol/l reduced the Ca2+ current. These results suggest that in single beta-cells of rat islets, CRF, through its own receptor, potentiates Ca2+ influx through the L-type Ca2+ channel by activation of the cAMP/protein kinase A signaling pathway. CRF at a high concentration also shows an inhibitory effect on the Ca2+ current through an unknown signaling pathway.

Three separate mitochondrial DNA sequences are contiguous in human genomic DNA.

We isolated from a HeLa genomic library 38 plaques that hybridized to total mitochondrial (mt) DNA isolated from human placenta. One clone (HLmt-17.8) hybridized to a 740 base-pair (12 S ribosomal RNA gene and displacement loop) mtDNA probe and was characterized in more detail. Within its 17.8 x 10(3) base-pair insert a 1.6 x 10(3) base-pair mtDNA fragment was similar to three non-sequential coding genes of human mtDNA, including a part of the 12 S ribosomal RNA (684-971), the cytochrome oxidase I (6553-7302), and two NADH dehydrogenase [ND4L/ND4] (10,606-11,159). The similarity to human mtDNA sequences was 92.0%, 92.3% and 92.4%, respectively, the highest degree of similarity to human mtDNA so far reported. This is also the first report of several adjacent mtDNA-like sequences in cellular chromosomes. The mtDNA-like sequences in HLmt-17.8 was found in the DNAs of human placenta, freshly isolated human leukocytes, foreskin and several human cell lines; but it was not present in other primates or lower organisms. The HLmt-17.8 mtDNA-like region appears to be a pseudogene that transferred into the nucleus in humans more recently than nine million years ago.

Ca2+ entry through the store-mediated pathway directly activates only the K+ current but the subsequent Ca2+ release from the store activates both K+ and Cl- currents in submandibular gland acinar cells of the rat.

The store-mediated Ca2+ entry was detected in single and cluster of rat submandibular acinar cells by measuring the Ca2+ activated ionic membrane currents. In the cells where intracellular Ca2+ was partly depleted by stimulation with submaximal concentration of acetylcholine (ACh) under a Ca2(+)-free extracellular condition, an employment of external Ca2+ in the absence of ACh caused a sustained increase of the K+ current without affecting the Cl- current. A renewed ACh challenge without external Ca2+ caused repetitive spikes of both K+ and Cl- currents due to the Ca2+ release. SK & F 96365 inhibited the generation of the sustained K+ current and refilling of the Ca2+ store following the Ca2+ readmission. It is suggested that the Ca2+ enters the cell through the store-mediated pathway new the K+ channels and is taken up by the store. Thus, only Ca2+ released from the store can activate both the K+ and Cl- currents.

Involvement of phosphorylation of beta-subunit in cAMP-dependent activation of L-type Ca2+ channel in aortic smooth muscle-derived A7r5 cells.

We investigated the effect of intracellular cAMP on the gating kinetics of L-type Ca2+ channel in an A7r5 smooth muscle-derived cell line using the whole-cell patch-clamp technique. Application of dibutyryl cyclic AMP (db-cAMP) to the cell increased the magnitude of Ca2+ currents through L-type Ca2+ channels (I(Ca)), and shifted the current-voltage relationship (I-V curve) for I(Ca) to the left. The magnitudes of maximum I(Ca) were 14.1 +/- 0.7 before and 16.0 +/- 1.1 pA/pF after application of 1 mM db-cAMP (P < 0.05). The values of the half-activation potential (V(1/2)) of I(Ca), estimated from activation curves, were -7.0 +/- 0.8 mV before and -10.8 +/- 1.0 mV after application of db-cAMP (P < 0.05). In cells pretreated with 10 microM Rp-cAMPS (a specific inhibitor of PKA), db-cAMP affected neither the I-V curve nor the activation curve for I(Ca). In cells pretreated with the antisense oligonucleotide for the beta-subunit of L-type Ca2+ channel, db-cAMP failed to enhance I(Ca) or alter the activation curve. On the other hand, in the cells pretreated with the nonsense oligonucleotide, application of db-cAMP caused an increase in magnitude of I(Ca) and shifted the activation curve to the left. Western blot analysis revealed that the pretreatment of cells with antisense oligonucleotide but nonsense oligonucleotide reduced the expression of the beta-subunit of the L-type Ca2+ channel. We conclude that the cAMP-dependent phosphorylation of the beta-subunit potentiates the voltage dependency of the activation kinetics of the L-type Ca2+ channel in A7r5 cells.

Oxidized LDLs but not native LDLs augment Ba2+ currents through L-type Ca2+ channels of the A7r5 smooth muscle-derived cell line.

The whole-cell patch-clamp method was used on A7r5 smooth muscle-derived cell line, and Ba2+ currents through Ca2+ channels were recorded. The A7r5 cells showed voltage-dependent, long-lasting Ba2+ currents which were markedly inhibited by nifedipine (10 microM). The magnitude of the maximum Ba2+ current (IBa(max)) was augmented by an application of dbcAMP (1 mM), but not affected by TPA (80 nM). Noradrenaline (NA) at 100 microM caused an increase in the IBa(max) by 19.7% in the presence of phentolamine (10 microM). This effect was cancelled by Rp-cAMPs (10 microM). In the presence of propranolol (10 microM), NA tended to reduce the IBa(max). Application of Ox-LDLs at 100 microg protein/ml caused an increase in the IBa(max) by 15.7%, whereas native LDLs did not change the IBa(max). Rp-cAMPs was ineffective to the Ox-LDL action on the IBa(max). In the presence of Ox-LDLs, NA augmented the IBa(max) by 21.4% in the presence of phentolamine. These results suggest that Ox-LDLs activate L-type Ca2+ channels of A7r5 cells by a mechanism independent of cAMP/PKA signalling.

Structural analysis of the gene encoding human 3 beta-hydroxysteroid dehydrogenase/delta 5----4-isomerase.

The structural gene encoding human 3 beta-hydroxysteroid dehydrogenase/delta 5----4-isomerase (3 beta HSD) was isolated from a human EMBL3 genomic library. The gene encompasses approximately 8 kilobases of DNA and is comprised of two large introns and three exons encoding amino acid residues 1-48, 49-103, and 104-373, respectively. The exonic sequence is identical to that of the cDNA that we previously isolated and expressed in COS 1 cells. DNA sequence analysis reveals a putative TATA (TATATAA) motif 26 basepairs up-stream of the beginning of exon I, as determined by S1 nuclease protection analysis. However, primer extension analysis using poly(A)+ RNA isolated from both placenta and corpora lutea indicates that the RNA initiates up-stream of the putative TATA motif, and that an additional 53-basepair exon, which is untranslated, is present 5' to the first coding exon. Southern hybridization analysis of genomic DNA using a single exon probe suggests that there may be more than one copy of the gene in the human genome. In addition, we confirm from Southern analysis of genomic DNA isolated from human x hamster somatic cell hybrids that the gene is located on human chromosome 1. These findings will provide a foundation for the characterization of apparent 3 beta HSD clinical deficiencies when these are due to a mutation in the structural gene.

Thimerosal modulates the agonist-specific cytosolic Ca2+ oscillatory patterns in single pancreatic acinar cells of mouse.

Modulation of the agonist-specific cytosolic Ca2+ oscillatory pattern by thimerosal has been investigated in single pancreatic acinar cells using patch-clamp perforated whole-cell recording to measure the calcium-dependent chloride current (I(C1)(Ca2+)). 1 microM thimerosal, which fails to evoke Ca2+ oscillation alone, clearly changed the pattern of Ca2+ oscillation from pulsatile spikes (evoked by low concentrations of activators) to sinusoidal or transient oscillations. The mimetic action of thimerosal was independent of extracellular Ca2+, was blocked by extracellular application of dithiothreitol or 10 mM caffeine, as well as by internal perfusion with heparin; but was unaffected by ruthenium red. We conclude that thimerosal modulates the agonist-specific cytosolic Ca2+ oscillatory patterns mediated by sensitizing the InsP3-induced Ca2+ release.

Molecular-genetic study of Duchenne and Becker muscular dystrophies: deletion analyses of 45 Japanese patients and segregation analyses in their families with RFLPs based on the data from normal Japanese females.

This study consisted of 1) molecular deletion analyses in patients with Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) using the entire cDNA for the DMD gene as hybridization probes, 2) RFLP analyses in a large number of Japanese normal women using 11 DMD-linked cloned DNAs as probes, and 3) segregation analyses with these RFLP data in 17 DMD families in which prenatal or carrier diagnosis was required. The deletion study showed that 18 (43%) of 42 male DMD patients had a deletion within the DMD gene, while no detectable deletion was found in 3 BMD patients. These deletions were preferentially observed at the 5' end of the DMD gene, while no deletion was found in the 3' portion of the gene. Of a total of 15 RFLPs detected with the 11 probes, one was a new RFLP (probe/enzyme: P20/MspI). In 6 RFLPs, the allele frequencies in the Japanese were statistically different from those in the Caucasian. Based on the RFLP data combined with the result of the deletion study, an estimated diagnostic rate for prenatal diagnosis and/or carrier detection in the Japanese DMD families was 63%. The real diagnostic rate obtained from the prenatal and carrier diagnoses, which were practically performed in 17 families, corresponded to the estimation. A protocol useful for the diagnosis in Japanese DMD families is presented.

Walker-Warburg syndrome is genetically distinct from Fukuyama type congenital muscular dystrophy.

A female patient who fulfilled the diagnostic criteria of Walker-Warburg syndrome had muscle biopsy finding of muscular dystrophy. There was normal expression of merosin (laminin alpha2 chain) and dystrophin and only slightly reduced dystrophin-associated glycoprotein expression. On genetic analysis, she had no specific haplotype, the common mutation of 3kb insertion, or point mutations in the Fukuyama-type congenital muscular dystrophy gene, suggesting that the two diseases are not genetically identical.

Spinal somatosensory evoked potentials in infants and children with spinal cord lesions.

Spinal somatosensory evoked responses to peroneal nerve stimulation were examined in 23 control subjects and 8 patients with pathological lesions of the spinal cord or peripheral nerve. In the control subjects, the response was found as a triphasic potential increasing in latency rostrally at the lumbar spinous recording location. Another negative potential following this triphasic potential appeared at the L1 to T10 spinous recording locations, which might reflect synaptic and/or post-synaptic activity in the spinal cord. This negative response then progressively increased in latency rostrally. The spinal conduction velocity was higher at the upper thoracic leads than at the lower leads. Three patients with spinal cord atrophy showed disappearance of the spinal evoked potential at the spinous recording location corresponding to the pathological lesion. However, since the triphasic potential at the lumbar spinous lead was undetectable in the patients with lesions of the peripheral nerve or cauda equina, the spinal cord function could not be estimated well in these patients.

Stimulated Ca2+ entry activates Cl- currents after releasing Ca2+ from the intracellular store in submandibular gland cells of the rat.

In order to examine whether Ca2+ entry is directly involved in controlling exocrine secretion, the Ca(2+)-activated Cl- currents were recorded in single and clusters of rat submandibular gland cells using the whole-cell patch-clamp method. Extracellularly applied acetylcholine (ACh, 10 nM) as well as intracellularly applied GTP gamma S and InsP3 caused repetitive transients of the Cl- currents activated by intracellular Ca2+. These responses occurred also in the absence of external Ca2+, but disappeared after several minutes. Readmission of Ca2+ to the extracellular solution restored the repetitive current transients, while introduction of Sr2+ failed to restore the current signals in spite of the presence of Sr2+ entry detected by microfluorimetry. On the other hand, direct application of Sr2+ to the cell inside caused activation of the Cl- currents although less effectively than Ca2+. When Ca2+ was introduced to the extracellular solution during an interruption of ACh stimulation after the ACh-induced depletion of intracellular Ca2+ store, the Cl- current was not elicited. However, a subsequent challenge with ACh at the same concentration in the absence of extracellular Ca2+ caused repetitive transient Cl- currents. The results suggest that in this cell type the stimulated Ca2+ entry does not by itself activate the Cl- currents but activates them indirectly by triggering Ca2+ release from the intracellular Ca2+ store which may take up Ca2+ soon after the Ca2+ entry.

Influence of boiling water treatment on surface roughness and surface microstructure of set gypsum (dental stone).

The influence of boiling water treatment on the surface roughness and surface microstructure of set gypsums was investigated. Typical surfaces before and after immersion in boiling water were compared by means of SEM observation, the Knoop hardness test, and a surface roughness test. The surfaces of set gypsums were rougher than that of an acrylic resin plate, and after immersion in boiling water, highly roughened surfaces and thinner crystal bodies were observed on each specimen under SEM. The knoop hardness of set gypsums was considerably lowered after boiling water immersion. That of die stones was the same or lower than set dental stones. The results showed that even brief immersion in boiling water had profound effects on the dental stone cast, resulting in rougher surfaces and lower hardness of set gypsums.

[Preliminary screening for antiviral AIDS drugs. VIII. Report for fiscal year 1995].

Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 96 samples of different origin tested, two were shown to inhibit the growth of HIV in vitro. One of the positive samples (plant origin) has hopeful signs, as the ranges of effective doses are wider than those of most of positive samples which had been found by us.

[Hypoplastic leukemia which achieved remission with administration of M-CSF along with low dose ara-C].

A 75-year-old female was admitted to our hospital because of fever and hypotension. The peripheral blood showed 400 leukocytes/microliters with 13,000/microliters platelets. Bone marrow puncture revealed that NCC stood at 14,000 with 50.0% blasts. The surface characters of the blasts were CD13+, CD33+, and HLA-DR+, and blood culture tests were positive. Coagulation tests revealed DIC. Based on the foregoing results, hypoplastic leukemia was diagnosed accompanied by sepsis and DIC, and was placed on the concomitant administration of a combination of low dose Ara-C and M-CSF. After 14 days of Ara-C administration and 26 days of M-CSF, her clinical symptoms improved, with the peripheral blood showing a WBC of 2,800/microliters and platelet count of 111,000/microliters. The percentage of myeloblasts decreased to 7.0%. After the administration of Ara-C was suspended for 2 weeks, another course of low dose Ara-C plus M-CSF administration was carried out and the patient achieved full remission. M-CSF stimulates not only the production of monocytes but increases the number of neutrophils and platelets through monocytes. It is also expected that tumoricidal activity may be realized by the activation of monocytes. In this patients, the concomitant administration of M-CSF and low dose Ara-C was remarkably effective in treating hypoplastic leukemia with severe complication. This result suggests that M-CSF will be useful for the treatment of leukemia.

[Short latency somatosensory evoked potentials following the peripheral nerve stimulation of lower extremities in children].

We have evaluated the short latency somatosensory evoked potentials (SSEPs) following peroneal and posterior tibial nerve stimulation in 27 normal children and adults, and then applied SSEPs examination following peroneal nerve stimulation to 6 children with neurological deficits. Features of the evoked potentials following peroneal nerve stimulation in normal children were almost similar to those in adults, but we found several points characteristic in children; a higher incidence of evoked potentials and a clearer appearance of "standing potential" at the lower thoracic vertebral level than in adults. Spinal afferent conduction velocity reached at a maximum at 3-4 years of age. The SSEPs following peripheral nerve stimulation in lower extremities are useful in pediatric neurology to determine the level of the spinal lesion, to reveal the distribution and pathophysiology of the spinal dysfunction, and to analyze the process of the disease progression.