Influence of Addition of Nickel on the Thermal Expansion, Rigidity Modulus and Its Temperature Coefficient of the Alloys of Cobalt, Iron and Chromium, Especially of Co-elinvar. I : Additions of 10 and 20 per cent of Nickel

The influence of additions of 10 and 20 per cent of nickel on the thermal expansion in the range from 10 to 50°, rigidity modulus at 20°and its temperature coefficient in the range from 20 to 50°of the alloys of cobalt, iron and chromium was studied. The relations between those properties and the concentrations of nickel-added alloys were almost similar qualitatively to those in the case of the ternary alloys of cobalt, iron and chromium, that is, there were two groups of alloys, one showing a positive temperature coefficient of rigidity modulus and the other a negative. In the case of addition of 10 per cent of nickel, the smallest thermal expansion coefficient was 2.20×10^, while in the case of addition of 20 per cent, it was 1.69×10^. The largest positive values of the temperature coefficients of rigidity modulus in the corresponding cases were respectively+46.7×10^ and + 66.0×10^. The largest and smallest values of rigidity modulus in the case of addition of 10 per cent of nickel were 9.10×10^5 kg/cm^2 and 6.00×10^5 kg/cm^2, and in the case of 20 per cent of nickel they were respectively 8.36×10^5kg/cm^2 and 5.09×10^5kg/cm^2

Thermal Expansion Coefficient, Rigidity Modulus and Its Temperature Coefficient of the Alloys of Iron, Nickel, Cobalt and Chromium, and Relations of Super Invar to Stainless Invar and of Elinvar to Co-Elinvar

The influence of an addition of chromium on the thermal expansion, rigidity modulus and its temperature coefficient of the alloys of iron, nickel and cobalt has been determined. It has been found that, in the relations of the thermal expansion cofficient or the temperature coefficient of rigidity modulus to the concentration of the alloys of iron, nickel, cobalt and chromium, there are two ranges of the minimum values of the expansion coefficient or the maximum values of the positive temperature coefficient of the modulus, one of which originates at the composition of invar, that is, in the neighbourhood of the composition of super invar, or elinvar in the binary system of iron and nickel, and the other at those of stainless invar or co-elinvar in the ternary system of iron, cobalt and chromium ; they come together at the section of 10 per cent of chromium of the quaternary system, showing that stainless invar or co-elinvar are closely connected respectively with invar (super invar) or elinvar, and also that the nickel and the cobalt contained in each alloy can be substituted almost linearly by each other

Electrostatic Potential of Human Immunodeficiency Virus Type 2 and Rhesus Macaque Simian Immunodeficiency Virus Capsid Proteins

Human immunodeficiency virus type 2 (HIV-2) and simian immunodeficiency virus isolated from a macaque monkey (SIVmac) are assumed to have originated from simian immunodeficiency virus isolated from sooty mangabey (SIVsm). Despite their close similarity in genome structure, HIV-2 and SIVmac show different sensitivities to TRIM5α, a host restriction factor against retroviruses. The replication of HIV-2 strains is potently restricted by rhesus (Rh) monkey TRIM5α, while that of SIVmac strain 239 (SIVmac239) is not. Viral capsid protein is the determinant of this differential sensitivity to TRIM5α, as the HIV-2 mutant carrying SIVmac239 capsid protein evaded Rh TRIM5α-mediated restriction. However, the molecular determinants of this restriction mechanism are unknown. Electrostatic potential on the protein-binding site is one of the properties regulating protein–protein interactions. In this study, we investigated the electrostatic potential on the interaction surface of capsid protein of HIV-2 strain GH123 and SIVmac239. Although HIV-2 GH123 and SIVmac239 capsid proteins share more than 87% amino acid identity, we observed a large difference between the two molecules with the HIV-2 GH123 molecule having predominantly positive and SIVmac239 predominantly negative electrostatic potential on the surface of the loop between α-helices 4 and 5 (L4/5). As L4/5 is one of the major determinants of Rh TRIM5α sensitivity of these viruses, the present results suggest that the binding site of the Rh TRIM5α may show complementarity to the HIV-2 GH123 capsid surface charge distribution

Multiple sites in the N-terminal half of simian immunodeficiency virus capsid protein contribute to evasion from rhesus monkey TRIM5α-mediated restriction

<p>Abstract</p> <p>Background</p> <p>We previously reported that cynomolgus monkey (CM) TRIM5α could restrict human immunodeficiency virus type 2 (HIV-2) strains carrying a proline at the 120^thposition of the capsid protein (CA), but it failed to restrict those with a glutamine or an alanine. In contrast, rhesus monkey (Rh) TRIM5α could restrict all HIV-2 strains tested but not simian immunodeficiency virus isolated from macaque (SIVmac), despite its genetic similarity to HIV-2.</p> <p>Results</p> <p>We attempted to identify the viral determinant of SIVmac evasion from Rh TRIM5α-mediated restriction using chimeric viruses formed between SIVmac239 and HIV-2 GH123 strains. Consistent with a previous study, chimeric viruses carrying the loop between α-helices 4 and 5 (L4/5) (from the 82^ndto 99^thamino acid residues) of HIV-2 CA were efficiently restricted by Rh TRIM5α. However, the corresponding loop of SIVmac239 CA alone (from the 81^stto 97^thamino acid residues) was not sufficient to evade Rh TRIM5α restriction in the HIV-2 background. A single glutamine-to-proline substitution at the 118^thamino acid of SIVmac239 CA, corresponding to the 120^thamino acid of HIV-2 GH123, also increased susceptibility to Rh TRIM5α, indicating that glutamine at the 118^thof SIVmac239 CA is necessary to evade Rh TRIM5α. In addition, the N-terminal portion (from the 5^thto 12^thamino acid residues) and the 107^thand 109^thamino acid residues in α-helix 6 of SIVmac CA are necessary for complete evasion from Rh TRIM5α-mediated restriction. A three-dimensional model of hexameric GH123 CA showed that these multiple regions are located on the CA surface, suggesting their direct interaction with TRIM5α.</p> <p>Conclusion</p> <p>We found that multiple regions of the SIVmac CA are necessary for complete evasion from Rh TRIM5α restriction.</p

Adrenomedullin in peritoneal effluent expressed by peritoneal mesothelial cells

BACKGROUND: Adrenomedullin (AM) possesses vasodilative and cell-protective properties. Glycine combines with the C-terminal of AM to form mature, physiologically active AM (mAM). AM is reportedly induced by high glucose condition in vascular endothelial or smooth muscle cells; however, little is known on how AM is activated by amidation. To investigate the behavior of AM in patients undergoing peritoneal dialysis (PD), the concentrations of AM, mAM and CA125 were measured. The mAM to AM ratio (mAM/AM ratio) was also evaluated as a marker of amidation activity. METHODS: Twenty patients were recruited for this study. The effluent at the time of the peritoneal equilibration test was collected and AM, mAM and CA125 concentrations were measured. The expression of AM in peritoneal mesothelial cells (PMCs) collected from effluent was also examined with an indirect immunofluorescent method. RESULTS: Mean values of AM and mAM in effluent were 18.1 ± 1.6 and 4.1 ± 0.3 fmol/mL, respectively. In plasma, they were 42.6 ± 3.3 and 5.6 ± 0.6 fmol/mL, respectively. AM concentrations in effluent did not correlate with plasma AM level but correlated well with the dialysate-to-plasma ratio of creatinine (D/P ratio of creatinine). Moreover, in 7 of 20 cases, concentrations of the mAM and mAM/AM ratio in effluent were higher than in plasma. In effluent, AM concentration but not the mAM/AM ratio correlated with CA125 concentration. Immunocytological study revealed diffuse, cytoplasmic expression of AM in PMCs which were collected from effluent during PD. CONCLUSION: AM is expressed by PMCs and actively amidated in the abdominal cavity of patients undergoing PD

Geographical, genetic and functional diversity of antiretroviral host factor TRIMCyp in cynomolgus macaque (Macaca fascicularis)

The antiretroviral factor tripartite motif protein 5 (TRIM5) gene-derived isoform (TRIMCyp) has been found in at least three species of Old World monkey: rhesus (Macaca mulatta), pig-tailed (Macaca nemestrina) and cynomolgus (Macaca fascicularis) macaques. Although the frequency of TRIMCyp has been well studied in rhesus and pig-tailed macaques, the frequency and prevalence of TRIMCyp in cynomolgus macaques remain to be definitively elucidated. Here, the geographical and genetic diversity of TRIM5α/TRIMCyp in cynomolgus macaques was studied in comparison with their anti-lentiviral activity. It was found that the frequency of TRIMCyp in a population in the Philippines was significantly higher than those in Indonesian and Malaysian populations. Major and minor haplotypes of cynomolgus macaque TRIMCyp with single nucleotide polymorphisms in the cyclophilin A domain were also found. The functional significance of the polymorphism in TRIMCyp was examined, and it was demonstrated that the major haplotype of TRIMCyp suppressed human immunodeficiency virus type 1 (HIV-1) but not HIV-2, whilst the minor haplotype of TRIMCyp suppressed HIV-2 but not HIV-1. The major haplotype of TRIMCyp did not restrict a monkey-tropic HIV-1 clone, NL-DT5R, which contains a capsid with the simian immunodeficiency virus-derived loop between α-helices 4 and 5 and the entire vif gene. These results indicate that polymorphisms of TRIMCyp affect its anti-lentiviral activity. Overall, the results of this study will help our understanding of the genetic background of cynomolgus macaque TRIMCyp, as well as the host factors composing species barriers of primate lentiviruses

A Single Amino Acid of Human Immunodeficiency Virus Type 2 Capsid Protein Affects Conformation of Two External Loops and Viral Sensitivity to TRIM5α

We previously reported that human immunodeficiency virus type 2 (HIV-2) carrying alanine or glutamine but not proline at position 120 of the capsid protein (CA) could grow in the presence of anti-viral factor TRIM5α of cynomolgus monkey (CM). To elucidate details of the interaction between the CA and TRIM5α, we generated mutant HIV-2 viruses, each carrying one of the remaining 17 possible amino acid residues, and examined their sensitivity to CM TRIM5α-mediated restriction. Results showed that hydrophobic residues or those with ring structures were associated with sensitivity, while those with small side chains or amide groups conferred resistance. Molecular dynamics simulation study revealed a structural basis for the differential TRIM5α sensitivities. The mutations at position 120 in the loop between helices 6 and 7 (L6/7) affected conformation of the neighboring loop between helices 4 and 5 (L4/5), and sensitive viruses had a common L4/5 conformation. In addition, the common L4/5 structures of the sensitive viruses were associated with a decreased probability of hydrogen bond formation between the 97th aspartic acid in L4/5 and the 119th arginine in L6/7. When we introduced aspartic acid-to-alanine substitution at position 97 (D97A) of the resistant virus carrying glutamine at position 120 to disrupt hydrogen bond formation, the resultant virus became moderately sensitive. Interestingly, the virus carrying glutamic acid at position 120 showed resistance, while its predicted L4/5 conformation was similar to those of sensitive viruses. The D97A substitution failed to alter the resistance of this particular virus, indicating that the 120th amino acid residue itself is also involved in sensitivity regardless of the L4/5 conformation. These results suggested that a hydrogen bond between the L4/5 and L6/7 modulates the overall structure of the exposed surface of the CA, but the amino acid residue at position 120 is also directly involved in CM TRIM5α recognition

Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic

BACKGROUND: During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study\u27s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines. METHODS: We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March-31 May 2020. The prior 1-year control period (1 March-31 May 2019) was obtained to account for seasonal variation. FINDINGS: There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI -24.3% to -20.7%, p\u3c0.0001). Embolisation of ruptured aneurysms declined with 1170-1035 procedures, respectively, representing an 11.5% (95%CI -13.5% to -9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI -28.0% to -22.1%, p\u3c0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile. INTERPRETATION: There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction