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Short-chain chlorinated paraffins (SCCPs) are listed in the Stockholm Convention. Therefore, selecting suitable methods for their accurate quantification is essential. Nowadays, the quality of commercial reagents employed as quantification standards is not guaranteed. As a solution, we adopted an SCCP formulation reference material with known homolog composition ratios as the quantification standard to evaluate the appropriateness of the methods. By mixing the SCCP formulation and interferences, an analytical sample was independently prepared and used as the simulation environmental sample. The homolog compositional profiles of the SCCPs resembled those of the quantification standard and the analytical sample. The mass fractions and the homolog profiles, including the carbon chain length and chlorine homolog profiles, of the SCCPs were reported by 14 different laboratories. For the mass fraction, the results reported by participants were consistent, except for the participants that employed low-resolution gas chromatography (GC). The results generated from liquid chromatography (LC) and GC were slightly different, despite of the similar homolog composition ratios between the quantification standard and the analytical sample. Although there were discreet discrepancies in the overall chlorine homolog profiles, the carbon chain length profiles acquired from GC and LC were similar. The differences depended on the method employed. Additionally, compared with the low-resolution data, the high-resolution data displayed less fluctuation since the effect of the interferences on the analytical sample was reduced because of the mass accuracy of high-resolution instruments. Accordingly, the interlaboratory trial employing the similar homolog compositional profiles of the quantification standard and the analytical sample proved valuable in elucidating the differences among methods, considering equipment, resolution specification, and ionization., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Chlorinated paraffins (CPs) are industrial chemicals that have been primarily used in applications involving metalworking fluids. Among CPs, short-chain chlorinated paraffins (SCCPs) are a well-known environmental pollutant and are listed under Annex A of the Stockholm Convention on Persistent Organic Pollutants. CPs are alkanes substituted with chlorine atoms, and SCCPs are comprised of 10-13 carbon atoms. Reliable quantification of SCCPs is a critical issue because of the large number of SCCP isomers that are in use across multiple industries. Some interlaboratory comparisons of SCCP analyses have been conducted, and the reliability of these results was overwhelmingly determined as inferior to that of comparable PCB and dioxin analyses because of variations in the quality of commercial reagents that were employed as quantification standards. In order to address such inconsistencies, this study endeavored to prepare and evaluate a novel SCCP formulation as a candidate reference material for use as a reliable quantification standard. A subject trial study was hence performed to evaluate methods such as gas- and liquid-chromatography mass spectrometry (GC/MS and LC/MS) on sample matrices (without a clean-up process), and to subsequently elucidate the interpreted specifications for their candidacy as a reliable quantification standard. Results ultimately showed that the SCCP concentrations obtained from GC and LC were comparable. When the homologs reported by a subset of 14 separate laboratories were unified (excluding all results for Cl 4 homologs), the carbon chain length profiles obtained from GC and LC were found to be similar; however, the overall chlorine homolog profiles did exhibit slight differences. Moreover, the results from high-resolution MS showed less variation than those from low-resolution MS. Thus, it was overarchingly determined that the deployment of this candidate reference material would serve as an effective mechanism for estimating the comparability of SCCP quantifications/evaluations of standard materials., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

3D image-guided brachytherapy (3D-IGBT) has become a standard therapy for cervical cancer. However, the use of 3D-IGBT is limited in East and Southeast Asia. This study aimed to clarify the current usage patterns of 3D-IGBT for cervical cancer in East and Southeast Asia. A questionnaire-based survey was performed in 11 countries within the framework of the Forum for Nuclear Cooperation in Asia. The questionnaire collected the treatment information of patients with cervical cancer who underwent 3D-IGBT. The cumulative external beam radiotherapy and 3D-IGBT doses were summarized and normalized to a biological equivalent dose of 2 Gy per fraction (EQD2) using a linear-quadratic model. Of the 11 institutions representing the participating countries, six (55%) responded to the questionnaire. Overall, data of 36 patients were collected from the six institutions. Twenty-one patients underwent whole-pelvic irradiation and 15 underwent whole-pelvic irradiation with central shielding. Patients received a median of four treatment sessions of 3D-IGBT (range, 2-6). All 3D-IGBT sessions were computed tomography (CT)-based and not magnetic resonance image-based. The median doses to the high-risk clinical target volume D90, bladder D2cc, rectum D2cc and sigmoid colon D2cc were 80.9 Gy EQD2 (range, 58.9-105.9), 77.7 Gy EQD2 (range, 56.9-99.1), 68.0 Gy EQD2 (range, 48.6-90.7) and 62.0 Gy EQD2 (range, 39.6-83.7), respectively. This study elucidated the current patterns of 3D-IGBT for the treatment of cervical cancer in East and Southeast Asia. The results indicate the feasibility of observational studies of CT-based 3D-IGBT for cervical cancer in these countries., (© The Author(s) 2020. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.)

Unlabelled: An HCV outbreak occurred in 2012 in China, affecting hundreds of patients. We characterized HCV subtype 2a and 6a sequences from 60 and 102 patients, respectively, and co-analyzed them with 82 local controls and 103 calibrating references. The close grouping of the patients׳ sequences contrasted sharply with the diversity of local controls. Scaled by the calibrating references, the emergence of patients׳ isolates was estimated at 2-5 years before sampling. In contrast, the controls intermingled with the calibrating references that were much older. For both subtypes, the major and minor clusters could be defined, with the closeness to indicate linked transmission., Conclusion: HCV sequences from the study patients grouped into three subtype 2a and two subtype 6a clusters, in addition to three 6a solitary branches, representing descendants of eight earlier strains that were distinct and otherwise sporadic. Due to iatrogenic transmission through reusing needles, five strains were highly selected and preferentially spread., (Copyright © 2015. Published by Elsevier Inc.)

Unlabelled: We investigated the migration patterns of hepatitis C virus (HCV) in China. Partial E1 and/or NS5B sequences from 411 volunteer blood donors sampled in 17 provinces and municipalities located in five large regions, the north-northeast, northwest, southwest, central south, and southeast, were characterized. The sequences were classified into eight subtypes (1a, n = 3; 1b, n = 183; 2a, n = 83; 3a, n = 30; 3b, n = 44; 6a, n = 55; 6n, n = 10; 6v, n = 1) and a new subtype candidate. Bayesian evolutionary analysis by sampling trees of the E1 sequences of the five major subtypes revealed distinct migration patterns. Subtype 1b showed four groups: one is prevalent nationwide with possible origins in the north-northeast; two are locally epidemic in the central south and northwest, respectively, and have spread sporadically to other regions; and the fourth one is likely linked to the long-distance dispersion among intravenous drug users from the northwest. Subtype 2a showed two groups: the larger one was mainly restricted to the northwest and seemed to show a trend toward migration via the Silk Road; the smaller one was geographically mixed and may represent descendants of those that spread widely during the contaminated plasma campaign in the 1990s. Subtype 3a exhibited three well-separated geographic groups that may be epidemically unrelated: one showed origins in the northwest, one showed origins in the southwest, and the other showed origins in the central south. In contrast, subtype 3b had a mixture of geographic origins, suggesting migrations from the southwest to the northwest and sporadically to other regions. Structurally resembling the tree for subtype 3a, the tree for subtype 6a showed four groups that may indicate migrations from the central south to southeast, southwest, and northwest. Strikingly, no subtype 6a strain was identified in the north-northeast., Importance: With a population of greater than 1.3 billion and a territory of >9.6 million square kilometers, China has a total of 34 provinces and municipalities. In such a vast country, the epidemic history and migration trends of HCV are thought to be unique and complex but variable among regions and are unlikely to be represented by those observed in only one or at best a few provinces and municipalities. However, due to the difficulties in recruiting patients, all previous studies for this purpose have been based only on data from limited regions, and therefore, geographical biases were unavoidable. In this study, such biases were greatly reduced because we utilized samples collected from volunteer blood donors in 17 provinces and municipalities. To our knowledge, this is the first study in which the HCV isolates represented such a large portion of the country, and thus, the results should shed light on the current understanding of HCV molecular epidemiology., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

Purpose: To report the long-term survival and toxicity of a multi-institutional phase 2 study of concurrent chemoradiation therapy (CCRT) for locally advanced cervical cancer in east and southeast Asia., Methods and Materials: Ten institutions from 8 Asian countries participated in the study. Between April 2003 and March 2006, 120 patients (60 with bulky stage IIB and 60 with stage IIIB) were treated with CCRT. Radiation therapy consisted of pelvic external beam radiation therapy and either high-dose-rate or low-dose-rate intracavitary brachytherapy. Five cycles of weekly cisplatin (40 mg/m(2)) were administered during the course of radiation therapy. Treatment results were evaluated by the rates of local control, overall survival, and late toxicities., Results: Median follow-up was 63.7 months, and the follow-up rate at 5 years was 98%. The 5-year local control and overall survival rates for all patients were 76.8% and 55.1%, respectively. The 5-year rates of major late toxicities of the rectum and bladder were 7.9% and 0%, respectively., Conclusions: The long-term results have suggested that CCRT is safe and effective for patients with locally advanced cervical cancer in east and southeast Asia. However, further efforts are needed to improve overall survival., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Aim: Genetic data were used to measure the phylogeographic distribution of the limpet, Cellana toreuma along the China coast in order to acsertain impacts of historic events, ocean currents and especially freshwater discharge from the Yangtze River on the connectivity of intertidal species with limited larval dispersal capability., Methodology/principal Findings: Genetic variation in 15 populations of C. toreuma (n = 418), ranging from the Yellow Sea (YS), East China Sea (ECS) and South China Sea (SCS), were determined from partial mitochondrial cytochrome c oxidase subunit I gene. Genetic diversity and divergence based on haplotype frequencies were analyzed using CONTRIB, and AMOVA was used to examine genetic population structure. Historic demographic expansions were evaluated from both neutrality tests and mismatch distribution tests. Among the 30 haplotypes identified, a dominant haplotype No. 1 (H1) existed in all the populations, and a relatively abundant private haplotype (H2) in YS. Pairwise F(ST) values between YS and the other two groups were relatively high and the percentage of variation among groups was 10.9%., Conclusions: The high nucleotide and gene diversity in the YS, with large pairwise genetic distances and relatively high percentages of variation among groups, suggests that this group was relatively isolated from ECS and SCS. This is likely driven by historic events, ocean currents, and demographic expansion. We propose that freshwater discharge from the Yangtze River, which may act as physical barrier limiting the southward dispersal of larvae from northern populations, is especially important in determining the separation of the YS group from the rest of the Chinese populations of C. toreuma.

Here, the complete genome sequences for three hepatitis C virus (HCV) variants identified from China and belonging to genotype 6 are reported: km41, km42 and gz52557. Their entire genome lengths were 9430, 9441 and 9448 nt, respectively; the 5' untranslated regions (UTRs) contained 341, 342 and 339 nt, followed by single open reading frames of 9045, 9045 and 9057 nt, respectively; the 3' UTRs, up to the poly(U) tracts, were 41, 51 and 52 nt, respectively. Phylogenetic analyses showed that km41 is classified into subtype 6k and km42 into subtype 6n. Although gz52557 clustered distantly with subtype 6g, it appeared to belong to a distinct subtype. Analysis with 53 and 105 partial core and NS5B region sequences, respectively, representing 17 subtypes from 6a to 6q and three unassigned isolates of genotype 6 in co-analyses demonstrated that gz52557 was equidistant from all of these isolates, indicating that it belongs to a novel subtype. However, based on a recent consensus that three or more examples are required for a new HCV subtype designation, it is suggested that gz52557 remains unassigned to any subtype.

Subtype 1b is the most common strain of Hepatitis C virus (HCV) in China. Here, the molecular epidemiology and epidemic history of this strain were investigated by conducting phylogenetic and population genetic analyses of E1 and NS5B gene sequences sampled from nine Chinese cities. The phylogenetic analysis indicated the presence of two clusters of Chinese strains that did not include reference strains from other countries, suggesting that these clusters represent two independent chains of HCV transmission within China. The remaining Chinese isolates were more closely related to reference strains from other countries. The date of origin and past population dynamics of the two groups were investigated using a new population genetic method, the Bayesian skyline plot. The estimated dates of origin of both groups coincide with the period of the Chinese 'Cultural Revolution' during the years 1966-1976. Both groups grew at a rapid exponential rate between approximately 1970 and approximately 1990, after which transmission slowed considerably. Possible explanations for the groups' fast spread and subsequent slowdown are discussed, including parenteral transmission by unsafe injection, iatrogenic transmission by infected blood or blood products and improvements in blood safety since 1990. These results shed light on HCV transmission in China and may help to predict the future burden of HCV-related disease in the country.

To determine hepatitis C virus (HCV) genotype distribution in China, a total of 148 HCV RNA positive serum samples were collected from nine geographic areas and subjected to RT-PCR followed by direct DNA sequencing and phylogenetic analysis of the core, E1, and NS5B regions. HCV was genotyped in 139 (93.9%) samples. Among them subtype 1b was the most predominant [66% (92/139)] followed by 2a [14% (19/139)]. Of 92 subtype 1b isolates, 35 (38%) and 30 (33%) formed two clusters, designated groups A and B. Group A was prevalent throughout China, while group B was predominant in the central and southern regions. In three cities in the Pearl River Delta, subtype 6a replaced 2a as the second most predominant subtype, and in Kunming (southwest) multiple HCV genotypes/subtypes were present. New variants of HCV genotype 6 were discovered in three samples from Kunming and one in Guangzhou in the Pearl River Delta., ((c) 2005 Wiley-Liss, Inc.)

We detected GBV-C/HGV sequences in the sera from 64 out of a total of 324 subjects in the south of China. In agreement with findings of others, we noted an especially high rate of infection among intravenous drug addicts and patients with chronic hepatitis C virus infection. The detection was achieved by nested PCR to amplify the 5' noncoding region (5'NCR) of the viral genome. Sequence analysis of the resulting 234 bp product revealed a total of 26 different sequences of which 25 were found to belong to the genotype G3, which is the most prevalent genotypes among Asian isolates, and one belonged to genotype G1, common among African isolates. The sequence divergence between the genotypes was largely clustered in a short variable region (V2) within the 5'NCR, and we showed that genotyping may be achieved equally well by analysis of this variable region as by the more detail analysis of the entire 5'NCR or of the entire viral genome.

The prevalence of GB virus C/hepatitis G virus (GBV-C/HGV) infection among intravenous drug users (IVDUs), patients with liver diseases, and blood donors in Nanning, southern China was studied. GBV-C/HGV RNA was detected by reverse transcription polymerase chain reaction with primers derived from the 5'-untranslated region. GBV-C/HGV RNA was detected in 64 of 85 IVDUs, 20 of 80 persons with liver disease, and 1 of 50 blood donors. Among IVDUs, GBV-C/HGV infection was associated with antibodies to hepatis C virus (HCV) and with hepatitis B surface antigen (HBsAg). Eleven nucleotide sequences were determined and analyzed by molecular evolutionary analysis. In a phylogenetic tree, the isolates were grouped in three clusters with GBV-C and HGV grouped in two clusters. These data indicate that GBV-C/HGV infection is common in China among IVDUs but uncommon among persons with liver disease without HBsAg or anti-HCV and that there is a new group of GBV-C/HGV.

A new kaurane type diterpene lactone, neotripterifordin (1), has been isolated from the roots of Tripterygium wilfordii. The structure of 1 was elucidated by spectroscopic methods, which included the concerted application of a number of 2-D NMR techniques including 1H-1H COSY, phase-sensitive NOESY, HETCOR, and long-range HETCOR. Compound 1 showed potent anti-HIV replication activity in H9 lymphocyte cells with an EC50 of 25 nM and TI of 125.