Retracted Article: A highest stable cluster Au58 (C1) re-optimized via a density-functional tight-binding (DFTB) approach

The vibrational spectrum ω_i of a re-optimized neutral gold cluster Au₅₈ has been calculated using a numerical finite-difference approach and the density-functional tight-binding (DFTB) method. We have exactly predicted the vibrational frequency ranging from 3.88 through to 304.49 cm⁻¹ which depends on the size and the arrangement of the atoms in the nanoparticle morphology of the cluster at ΔE = 0. Our investigation has revealed that the vibrational spectrum is strongly influenced by size and structure. It is well known that gold atomic clusters can have planar or hollow cage-like structures due to their relativistic effect. However, in our study, by first principles calculations on a Au₅₈ cluster we have proposed that gold clusters of medium size can form a shell-like structure (skeleton/helmet), this is demonstrated by the remarkable robustness of a double shell structure with a hollow inner shell of about ten atoms. Finally, the structure symmetry (C₁) is confirmed through the cluster size, vibrational spectroscopy, and by studying the effect of temperature on a neutral gold cluster for the first time.

The vibrational spectrum ω_i of a re-optimized neutral gold cluster Au₅₈ has been calculated using a numerical finite-difference approach via a density-functional tight-binding (DFTB) method.     

一起学校甲型H1N1流感聚集性疫情的调查

浙江省嘉兴市秀洲区一所中学自2009年9月2日报告首例甲型H1N1病例,至9月10日共报告13例,无重症死亡病例,罹患率为0.72%(13/1800);8月31日开学至9月18日末例流感样病例,共诊断41例,罹患率为2.28%;发病高峰均在开学一周内。由于宣传沟通到位,未造成恐慌现象;传染源及时隔离使得本次疫情控制及时有效。     

Estimation of immune complexes by a microplate-adapted C1q-Protein A enzyme-linked-immunosorbent-assay (C1q-PA-ELISA)

A microplate-adapted enzyme linked immunosorbent assay (ELISA) for detection of C1q-binding immune complexes (IC) and aggregated IgG (delta IgG) is described. Purified human C1q was adsorbed to the wells of flat-bottomed microtiter plates and EDTA-treated serum samples were subsequently introduced. Bound IC was measured by use of alkaline phosphatase-labelled Protein A followed by the substrate para-nitro-phenyl-phosphate. A dose response was found for both delta IgG and BSA anti-BSA complexes, while variations in the concentration of monomer IgG did not affect the optical density. Elevated levels of IC were found in the majority of sera from patients with rheumatoid arthritis and SLE. The described C1q-PA-ELISA is a simple and inexpensive method for detection of C1q-binding immune complexes. The reproducibility is acceptable and the sensitivity is higher than for most IC-methods based on C1q-binding.     

pain1: a neuropathic pain QTL on mouse chromosome 15 in a C3HxC58 backcross

We have produced a backcross (BC) population of 267 mice from the parental strains C3H/HeN and C58/J. The mice were phenotyped for neuropathic pain using the neuroma model. Subsequently all BC mice were genotyped in a region of chromosome 15 that has been previously suggested to contain a quantitative trait locus (QTL) for this trait. We have confirmed the linkage of the QTL, named pain1, to the central region of chromosome 15. Our finding provides the necessary robustness to justify efforts towards identification of the underlying gene.     

Pharmacokinetics of gentamicin C(1), C(1a), and C(2) in beagles after a single intravenous dose

The pharmacokinetics of gentamicin C(1), C(2), and C(1a) were studied in six beagles after administration of gentamicin at 4 mg/kg of body weight as a single intravenous bolus dose. Plasma concentrations of the gentamicin components were analyzed with a novel high-performance liquid chromatography method capable of identifying and quantifying each of the components. The pharmacokinetic analysis of the plasma concentration-versus-time data was performed using the noncompartmental approach. The results indicated significant differences in the pharmacokinetic characteristics between the gentamicin components C(1), C(1a), and C(2). The mean residence times of gentamicin C(1), C(1a), and C(2) were 81+/-13, 84+/-12, and 79+/-13 min (mean +/- standard deviation), respectively. The half-lives of the respective components were 64+/-12, 66+/-12 and 63+/-12 min. Clearance (CL) of gentamicin C(1), 4.62+/-0.71 ml min(-1) kg(-1), was significantly higher (P = 0.0156) than CL of gentamicin C(1a), 1.81+/-0.26 ml min(-1) kg(-1), and C(2), 1.82+/-0.25 ml min(-1) kg(-1). Similarly, the volume of distribution at steady state (V(ss)) of gentamicin C(1), 0.36+/-0.04 liter kg(-1), was significantly higher (P = 0.0156) than the V(ss) of gentamicin C(1a), 0.14+/-0.01 liter kg(-1), and C(2), 0.15+/-0.02 liter kg(-1). Tissue binding was considered the most likely cause for the difference. The difference may have clinical and toxicological significance.     

No involvement of the calcium channel gene (CACNA1A) in a family with cluster headache

It is very likely that genetic factors play a role in the pathophysiology of cluster headache (CH). As CH shares its paroxysmal character with migraine, and migraine has been described in coexistence with CH in some families, we hypothesized that both diseases might share a genetic aetiology. In this study, we tested whether the migraine CACNA1A gene on chromosome 19 is involved in CH in an extended pedigree. Haplotype analysis did not reveal an obvious disease haplotype, and SSCP analysis of all 47 exons of the CACNA1A gene did not reveal a causative mutation. CH in this family is not caused by mutations in the CACNA1A gene.     

21例经胸骨前路径腔镜甲状腺切除术

目的探讨腔镜甲状腺切除术的可行性及安全性。方法经胸骨前路径行腔镜甲状腺切除术21例。其中甲状腺瘤13例、结节性甲状腺肿4例、原发性甲状腺机能亢进4例,行甲状腺瘤摘除术6例,单侧甲状腺次全切除11例,双侧甲状腺次全切除4例。结果手术过程顺利,平均手术时间(116±16.7)min,平均术中出血(40.0±23.6)mL,无中转开放手术,术后2、3d拔除引流管,无声嘶或甲状旁腺损伤等并发症,平均住院时间(7±3.5)d,术后随访3～14个月,无复发病例,美容效果满意。结论腔镜甲状腺手术是安全、有效、可行的。     

Identification of the coumermycin A(1) biosynthetic gene cluster of Streptomyces rishiriensis DSM 40489

The biosynthetic gene cluster of the aminocoumarin antibiotic coumermycin A(1) was cloned by screening of a cosmid library of Streptomyces rishiriensis DSM 40489 with heterologous probes from a dTDP-glucose 4,6-dehydratase gene, involved in deoxysugar biosynthesis, and from the aminocoumarin resistance gyrase gene gyrB(r). Sequence analysis of a 30.8-kb region upstream of gyrB(r) revealed the presence of 28 complete open reading frames (ORFs). Fifteen of the identified ORFs showed, on average, 84% identity to corresponding ORFs in the biosynthetic gene cluster of novobiocin, another aminocoumarin antibiotic. Possible functions of 17 ORFs in the biosynthesis of coumermycin A(1) could be assigned by comparison with sequences in GenBank. Experimental proof for the function of the identified gene cluster was provided by an insertional gene inactivation experiment, which resulted in an abolishment of coumermycin A(1) production.     

A convenient approach to difluoromethylated all-carbon quaternary centers via Ni(ii)-catalyzed enantioselective Michael addition

A Ni(ii)-catalyzed enantioselective Michael addition of 2-acetyl azarenes with β-difluoromethyl substituted nitroalkenes was successfully realized, which afforded chiral CF₂H-containing compounds in good enantioselectivities (up to 93% ee). This protocol provides a new convenient approach to all-carbon quaternary stereogenic centers featuring a CF₂H group.

Ni(ii)-catalyzed enantioselective Michael addition afforded compounds with all-carbon quaternary stereogenic centers featuring a CF₂H group in good enantioselectivities.     

Retraction: Experimental and theoretical studies of the nanostructured {Fe3O4@SiO2@(CH2)3Im}C(CN)3 catalyst for 2-amino-3-cyanopyridine preparation via an anomeric based oxidation

Retraction of ‘Experimental and theoretical studies of the nanostructured {Fe₃O₄@SiO₂@(CH₂)₃Im}C(CN)₃ catalyst for 2-amino-3-cyanopyridine preparation via an anomeric based oxidation’ by Mohammad Ali Zolfigol et al., RSC Adv., 2016, 6, 50100–50111, https://doi.org/10.1039/C6RA12299J.

The Royal Society of Chemistry hereby wholly retracts this RSC Advances article as the synthesis of {Fe₃O₄@SiO₂@(CH₂)₃Im}C(CN)₃ reported in the article, whereby tricyanomethane is used as a starting material, is not reproducible. The authors stated that they did not report the synthesis of tricyanomethane in the published paper as they purchased this compound from a commercial center and used it in the synthesis of ionic liquids, molten salts and various kinds of catalysts. The authors thought the reaction between tricyanomethane and organic bases is a simple acid–base reaction, therefore they did not cite the previously reported literature and its related history for the preparation of tricyanomethane. However, according to papers by Banert et al.,^1,2 and based on their obtained analysis of the chemical sold to them as tricyanomethane, it became clear to the authors that this purchased compound was not tricyanomethane as there were differences in the ¹H NMR and ¹³C NMR chemical shift between the purchased compound and the reports of Banert et al.¹ According to these documents, the authors believe that the compound sold to them as tricyanomethane was fake. While the authors have now re-prepared {Fe₃O₄@SiO₂@(CH₂)₃Im}C(CN)₃, by synthesising potassium tricyanomethanide as a starting material for the synthesis,^3–5 the synthesis reported in this article is not accurate. Therefore, this article is being retracted to avoid misleading readers and to protect the accuracy and integrity of the scientific record.Mohammad Ali Zolfigol and Meysam Yarie oppose the retraction. Mahya Kiafar, Avat (Arman) Taherpour and Mahdi Saeidi-Rad were contacted but did not respond.Signed: Laura Fisher, Executive Editor, RSC AdvancesDate: 17^th August 2022     

Quantitative variations of the C3b/C4b receptor (CR1) in human erythrocytes are controlled by genes within the regulator of complement activation (RCA) gene cluster

The genetic relationships of quantitative and structural variations of the C3b/C4b receptor (CR1) in human erythrocytes have been analyzed in informative families. Our results demonstrate the existence of multiple discrete quantitative variations of CR1 controlled by a locus, C3bRQ, closely linked to the CR1 structural locus, C3bR. Since the amounts of CR1 produced by each C3bR allele are shown to be independently regulated, we propose that a cis-acting genetic mechanism controls the level of expression of the C3bR alleles, and that this quantitative control plays a major, if not the sole, role in determining the total amounts of CR1 on normal human erythrocytes.     

Comparison between subgenomic replicons of hepatitis C virus genotypes 2a (JFH-1) and 1b (Con1 NK5.1)

Although replicon systems for hepatitis C virus (HCV) recently developed have enabled the replication of HCV in cultured cells, limited genotypes are available for them. We have isolated HCV cDNA of genotype 2a (JFH-1 strain) from serum of a patient with fulminant hepatitis. A subgenomic replicon of JFH-1 was constructed and compared with the HCV replicon of genotype 1b (Con1 NK5.1) which possessed adaptive mutations. Huh7 cells transfected with replicon RNAs that had been transcribed in vitro were cultured in the presence of neomycin sulfate (G418), and selected colonies were isolated and expanded. Then, growth rates and replication of HCV RNA were evaluated on isolated cells hosting replicons. Saturation densities were lower for cells propagating JFH-1 than Con1 NK5.1 or untransfected Huh7 cells, and the mean doubling time was longer for JFH-1 than for Huh7 cells. Levels of HCV RNA replication in isolated clones were similar between JFH-1 and Con1 NK5.1 cells. Replication of RNA decreased reciprocally with cell densities in both JFH-1 and Con1 NK5.1 cells. The replication of HCV RNA was more resistant to interferon-alpha in JFH-1 than in Con1 NK5.1 cells based on the comparison of an inhibitory concentration of 50%. In conclusion, we found differences between HCV replicon clones of genotypes 1b and 2a. However, these differences may result from strain-specific characteristics, such as the source of HCV, rather than characteristics of distinct genotypes. Therefore, further investigation may be needed on more HCV isolates of diverse genotypes.