CRITICAL CURRENT DENSITIES AND N-VALUES OF MGB2 CONDUCTORS FOR SMES, MRI, AND LOW AC LOSS APPLICATIONS

Multifilamentary MgB 2 strands (filament numbers 36 to 114) prepared by the in-situ power-in-tube (PIT) route with carbon doping contents of 0, 2, and 3.2% were wound on barrels for transport J c and n -value measurement at 4.2 K in fields of up to 12 T. The strand and gauge lengths were 1 m and 0.5 m. Heat treatments at 675 °C and 650 °C centered around the melting point of Mg (650 °C) and both utilized the liquid-solid reaction. A pair of strands, with and without 2% C doping exhibited the J c (B) crossover effect. Studied were the dependencies of J c on field strength, dopant concentration, and cabling and the dependence of n -value on field strength.

Mechanism of enhanced critical fields and critical current densities of MgB2 wires with C/Dy2O3 co-additions

A series of monofilamentary powder-in-tube MgB2 wires were fabricated with 2 mol. % C doping and co-additions of 0-3 wt. % Dy2O3. Irreversibility fields (μ 0 Hirr ), upper critical fields (μ 0 Hc 2), and transport critical currents were measured, and from these quantities, anisotropies ( γ ) and electronic diffusivities ( D π , σ ) were estimated. The addition of 1 wt. % Dy2O3 to already optimally C-doped MgB2 wires produced higher Hc 2//ab , Hc 2//c , and Hirr values at 4.2 K. In addition, the critical current density, Jc , increased with Dy2O3 concentration up to 1 wt. % where non-barrier Jc reached 4.35 × 104 A/cm2 at 4.2 K, 10 T. At higher temperatures, for example, 20 K and 5 T, co-additions of 2 mol. % C and 2 wt. % Dy2O3 improved non-barrier Jc by 40% and 93% compared to 2 and 3 mol. % C doping, respectively. On the other hand, measurements of Tc showed that C/Dy2O3 co-additions increase interband scattering rates at a lower rate than C doping does (assuming C doping levels giving similar levels of low-T μ 0 Hc 2 increase as co-addition). Comparisons to a two-band model for μ 0 Hc 2 in MgB2 allowed us to conclude that the increases in Hc 2//ab , Hc 2//c , and Hirr (as well as concomitant increases in high-field Jc ) with Dy2O3 addition are consistent with increases primarily in intraband scattering. This suggests C/Dy2O3 co-addition to be a more promising candidate for improving non-barrier Jc of MgB2 at temperatures above 20 K.

A brief introduction to chemical proteomics for target deconvolution

OBJECTIVE

Drug-target relationships provide the basis for network-based polypharmacology, and target deconvolution is a key step in phenotypic-screening based drug discovery. Due to the complexity of the mammalian proteomics and the often-limited affinity of the lead compound, it is challenging to identify the drug targets, especially when the goal is to identify all targets. This paper attempts to provide a brief and comprehensive introduction to the various methods in chemical proteomics for target deconvolution by categorizing them into two groups: the biochemical enrichment and the proteomics-screening methods. Moreover, a brief introduction of related Mass Spectrometry techniques is also provided, together with recent progress.

MATERIALS AND METHODS

The data for this review were queried from Web of Science and PubMed, the keywords used were Drug targets, Target deconvolution, and Chemical Proteomics. A total of over 500 relevant articles, with a time limit from 1953 to 2022, were identified according to search strategy. Duplicate records and review articles were excluded by their titles and abstracts. Finally, we found about 120 articles matching our inclusion criteria, which covered representative research and reviews of various target discovery methods.

RESULTS

Existing target discovery methods can be grouped into either biochemical enrichment or the proteomics-screening methods, with the recent emergence of a hybrid method combining these two such as lysine reactivity profiling. The advantage of the biochemical enrichment method is the ease of operation and the comprehensive target coverage. However, most biochemical enrichment methods require a high-affinity binding of the drug to the target proteins and cannot differentiate direct/indirect targets. The proteomics-screening methods do not require drug modification but have limited protein coverage, and most of them cannot differentiate direct/indirect targets.

CONCLUSIONS

Although existing target discovery methods have greatly facilitated pharmacological research, each of these methods has advantages and disadvantages. New strategies/methods are needed to further improve both the coverage of the proteosome and the specificity.

Magnetic, Mechanical and Thermal Modeling of Superconducting, Whole-body, Actively Shielded, 3 T MRI Magnets Wound Using MgB2 Strands for Liquid Cryogen Free Operation

we present magnetic, mechanical and thermal modeling results for a 3 Tesla actively shielded whole body MRI (Magnetic Resonance Imaging) magnet consisting of coils with a square cross section of their windings. The magnet design was a segmented coil type optimized to minimize conductor length while hitting the standard field quality and DSV (Diameter of Spherical Volume) specifications as well as a standard, compact size 3 T system. It had an overall magnet length and conductor length which can lead to conduction cooled designs comparable to NbTi helium bath cooled 3 T MRI magnets. The design had a magnetic field homogeneity better than 10 ppm (part-per-million) within a DSV (Diameter of Spherical Volume) of 48 cm and the total magnet winding length of 1.37 m. A new class of MgB₂ strand especially designed for MRI applications was considered as a possible candidate for winding such magnets. This work represents the first magnetic, mechanical and thermal design for a whole-body 3 T MgB₂ short (1.37 m length) MRI magnet based on the performance parameters of existing MgB₂ wire. 3 Tesla MRI magnet can operate at 20 K at 67 % of its critical current.

Distinct soil microbial communities under Ageratina adenophora invasions

Ageratina adenophora is one of the most hazardous invasive weeds in China. It can form a single species community quickly and cause extensive ecological harm. The belowground microbial community can participate in nutrient transformation in soil and plays an important role in the invasiveness of exotic plant species. We selected sampling sites with different invasion levels of A. adenophora. The soil property and soil biogeochemical activity were measured in both bulk and rhizosphere soil under the aggressive weed A. adenophora and under adjacent native plants. The composition of bacterial communities was investigated using high-throughput 16S rRNA gene sequencing. We found that the rhizosphere habitat selectively accumulated Sphingomonas and Steroidobacter and reduced the abundance of Gaiella and Gp6 regardless of plant host. The presence of A. adenophora caused a switch in microbial composition from Aeromicrobium and Marmoricola to Reyranella and Bradyrhizobium in the bulk soil, and from Gp4, Pirellula, Lysobacter and Aridibacterrae to Reyranella and Streptomyces in the rhizosphere soil. We also revealed specific microbes that closely related with N-cycling processes. In addition, soil pH was the main factor affecting microbial communities in both bulk and rhizosphere soil. Our study confirmed that the rhizosphere environment imposed homogenous microbial communities. The invasion of A. adenophora selected specialized bacterial communities in soils and specific microbes that potentially mediated soil nutrition cycling. Our findings provide ecological explanation to explain how the underground microbes help A. adenophora invasive.

[Textual research on lost ancient Chinese medical books in Bencao Tujing]

Bencao Tujing(, Illustration Classics for Materia Medica) occupies an irreplaceable academic position in the academic history of Chinese Materia Medica. It was written in the early Song Dynasty. The contents of Chinese medical books before Song Dynasty have not been revised by Song Dynasty officials, and the original appearance of earlier documents have been preserved. Domestic and foreign scholars mainly focus on the textual research of Chinese Materia medica patterns, and academic value research. The special research on the Lost ancient Chinese medical books were relatively rare. According to the names of"XX Fang"or"Someone Fang"in Bencao Tujing, about 46 kinds of Lost ancient Chinese medical books have been found. Taking Wei Zhou's Du Xing Fang, Liu Yuxi's Chuan Xin Fang, Tian Bao Dan Fang Tu (Tian Bao Dan Xing Fang) as examples, it is found that Lost ancient Chinese medical books recorded in Bencao Tujing have abundant materials and clear clues, which have further exploration space for the research and collection of Chinese medical books.

[Levels of sgRNA as a Major Factor Affecting CRISPRi Knockdown Efficiency in K562 Cells]

To determine how nuclease deactivated Cas9 (dCas9) or single-guide RNA (sgRNA) expression levels affect the knockdown efficiency of CRISPRi, we created K562 cell clones expressing KRAB-dCas9 protein either with the inducible Tet-on system or with the constitutive SFFV promotor. Single clones were selected by fluorescence-activated cell sorting (FACS) for further study. Six genes with various expression levels were targeted using lentiviral sgRNA from two libraries in four cell clones with various KRAB-dCas9 expression levels. The expression level of dCas9 protein/sgRNA levels and the knockdown efficiency were determined by flow cytometry. The cell clone with the highest KRAB-dCas9 expression level achieved effective CRISPRi knockdown. The data describing this clone were statistically different from that on other clones, indicating the strong KRAB-dCas9 expression might be a prerequisite for CRISPRi. By adopting different multiplicity of infection (MOI) in lentiviral transduction of this clone, we modified the expression level of sgRNA and found that the knockdown efficiency was neither affected by the target gene expression level nor correlated with KRAB-dCas9 levels, which remained relatively constant across all knockdown experiments (coefficient of variation = 2.2%). As an example, the following levels of the knockdowns: 74.72, 72.28 and 39.08% for mmadhc, rpia and znf148 genes, respectively, were achieved. These knockdown efficiencies correlated well with the respective sgRNA expression levels. Linear regression models built using this data indicate that the knockdown efficiency may be significantly affected by the levels of both KRAB-dCas9 and sgRNA. Notably, the sgRNA levels have greater impact, being a major factor affecting CRISPRi efficiency.

The Role of CHPD and AIMI processing on enhancing J C and transverse connectivity of in-situ MgB2 strand

Research into in-situ MgB2 strand has been focused on improvements in J C through reduction of porosity. Both of cold-high-pressure-densification (CHPD) and advanced-internal-magnesium-infiltration (AIMI) techniques can effectively remove the voids in in-situ MgB2 strands. This study shows the nature of the reduced porosity for in-situ MgB2 strands lies on increases in transverse grain connectivity as well as longitudinal connectivity. The CHPD method bi-axially applying 1.0 GPa and 1.5 GPa yielded 4.2 K J CM∥s of 9.6 × 104 A/cm2 and 8.5 × 104 A/cm2 at 5 T, respectively, with compared with 6.0 × 104 A/cm2 for typical powder-in-tube (PIT) in-situ strand. Moreover, AIMI-processed monofilamentary MgB2 strand obtained even higher J Cs and transverse grain connectivity than the CHPD strands.

[Textual research on lost articles in Mei Shi Fang]

Mei Shi fang() is a lost medical prescription book. Its title came from the "book of classics and history" , a chapter of Zhenglei Bencao (, Collected Classified Materia Medica). 117 pieces of lost articles were preserved in the book. In addition to Zhenglei Bencao, a total of 50 kinds of medical books explicitly quoted some of the lost articles in Mei Shi Fang. Among them, 38 kinds of medical books did not exceed the scope of the articles of Mei Shi Fang cited in Zhenglei Bencao, 12 kinds of medical books contained the articles of Mei Shi Fang which did not quoted in Zhenglei Bencao. It is speculated that Mei Shi Fang may still exist in the Yangtze River basin from 1552 to 1578. In terms of the existing articles of Mei Shi Fang, it has academic origin with Zhouhou Beiji Fang (, Handbook of Prescriptions for Emergency).

Induced Thermotolerance and Expression of Three Key Hsp Genes (Hsp70, Hsp21, and sHsp21) and Their Roles in the High Temperature Tolerance of Agasicles hygrophila

Thermal adaptation plays a fundamental role in the expansion and distribution of insects, and heat shock proteins (Hsps) play important roles in the temperature adaptation of various organisms. To determine the roles of Hsp genes (Hsp70, Hsp21, and sHsp21) on the high temperature tolerance of Agasicles hygrophila, we obtained complete cDNA (complementary DNA) sequences for Hsp70, Hsp21, and sHsp21 by rapid amplification of cDNA ends (RACE), analyzed their expression profiles under different high temperature treatments by quantitative reverse transcription polymerase chain reaction (RT-qPCR), and performed functional verification by RNA interference (RNAi). The open reading frames of Hsp70, Hsp21, and sHsp21 were 1940, 543, and 567 bp, encoding 650, 180, and 188 amino acids, respectively. Their molecular weights (MWs) were 71.757, 20.879, and 21.510 kDa, and the isoelectric points were 5.63, 6.45, and 6.24, respectively. Phylogenetic tree analysis showed that the Hsp70, Hsp21, and sHsp21 genes of A. hygrophila were relatively conserved in evolution. The Hsp70 and Hsp21 genes in A. hygrophila were homologous to those in Leptinotarsa decemlineata (87 and 79% similarity, respectively), and the sHsp21 gene in A. hygrophila was homologous to that in Lissorhoptrus oryzophilus (74% similarity). The amino acid polypeptide chain had highly conserved sequences of DLGGGTFD, VLVGGSTR, and GPTIEEVD. The sequence of EEVD was the characteristic motif of cytoplasmic Hsp70, and the highly conserved sequences of MALFR and MSLLP were characteristic sequences of Hsp2 and sHsp21, respectively. Relative quantitative real time PCR showed that the three Hsps could be induced by 4-h treatment at high temperatures. Significant upregulation of these Hsps was observed when the temperature was further increased. The RNAi results showed that the injection of the three Hsps' dsRNA could suppress the expression at the gene level significantly. Compared with the control group, high temperature heat shock reduced the fecundity of A. hygrophila significantly, and the fecundity decreased with the increase in temperature. Our results suggest that Hsp70, Hsp21, and sHsp21 might play key roles in high temperature adaptation of A. hygrophila and help improve our understanding of their mechanism of thermotolerance.

[Shang Zhijun, a famous contemporary philogist in herbal literature research]

Mr. Shang is a famous herbalist in contemporary China and he devoted his life to the research of herbal literatures. During his lifetime, he has compiled and published a total 19 herbal literatures, 33 works of herbal literature, 268 academic papers, and more than 20 million words of handwritten herbal transcripts. In the field of herbal literature research, he has achieved fruitful results that are highly recognized by the academic communities. The research results can be roughly summarized as four aspects: the establishment of a two-line research network of herbal formulae, the research and collection of lost herbal works, the collation of the survived ancient herbal works and the textual research of famous herbal works. Many of his research results on herbal literature have been included in the modern higher education professional textbooks, and his outstanding academic achievements have opened the door for later scholars, influencing many scholars both home and abroad.

[Probe of the compiling stylistic rules and layout of Youyou Xin Shu]

Youyou Xin Shu(The New Book on Juveniles)《》is a great book of pediatrics in the Southern Song Dynasty. The book quotes a lot of literature.This paper makes an overall arrangement of the citation, sums up the features of the books cited, corrects some wrong compilations from different texts in various existing versions. Therefore, we can infer the publishing ages and time of some literature related.

Laboratory comparison of two Aphelinus mali clades for control of woolly apple aphid from Hebei Province, China

Aphelinus mali (Haldeman) is an effective natural enemy of woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). Previous studies have found that, with WAA from Shandong Province (Qingdao) as the host, there are significant differences in various biological characteristics between a Shandong clade and Liaoning clade of A. mali. The ability of the Shandong clade to control this aphid was significantly higher than that of the Liaoning clade in Shandong Province. In order to determine whether differences were caused by better adaptation of the Shandong parasitoid clade to the population of the host in that province or if it represents a more general fitness of this clade to control the host regardless of location, we compared the same parasitoid clades with hosts from Hebei Province. We found no significant differences in the developmental threshold temperature, effective accumulated temperature, fecundity, longevity, and oviposition period of the two clades, but the duration of host searching of the Shandong clade was significantly longer than that of the Liaoning clade. The instantaneous attack rate, the control ability (a/Th), the search parameter (Q) of the Shandong clade (0.0946, 0.543, 0.0725) of A. mali were higher than that of the Liaoning clade (0.0713, 0.382, 0.0381), and therefore, with WAA from Hebei Province as the host, the host adaptability of the Shandong clade of A. mali was not worse than that of the Liaoning clade, while the pest control ability of the Shandong clade was still greater than that of the Liaoning clade.

[Comparison of outcomes of two minimally invasive approaches for multi-vessel coronary revascularization]

OBJECTIVE

To compare the safety and effectiveness of two minimally invasive approaches for multi-vessel coronary revascularization.

METHODS

From August 2014 to February 2017, 70 consecutive patients who underwent minimally invasive coronary artery bypass grafting in Peking University Third Hospital were randomly divided into two groups. In one group, 40 patients underwent staged-hybrid coronary revascularization (staged-HCR) treatment; in the other group, 30 patients underwent minimally invasive total arterial revascularization with bilateral internal thoracic artery (BITA). In staged -HCR group, the patients underwent minimally invasive direct coronary artery bypass grafting (MIDCAB) and percutaneous coronary intervention (PCI) procedure for treatment of multi-vessel disease. In BITA group, the patients underwent total arterial coronary artery bypass grafting with composite "Y" BITA graft. Preoperative and postoperative data of the two groups, including postoperative blood usage, mechanical ventilation time, domiciling duration in intensive care unit (ICU), major adverse cerebral and cardiovascular event (MACCE), and postoperative coronary angiography results were compared, in order to evaluate the safety and effectiveness of these surgical approaches.

RESULTS

The preoperative characteristics of 70 patients in the two groups showed no significant difference. All the patients underwent successfully, elective minimally invasive multi-vessel coronary artery bypass grafting as scheduled preoperatively. Postoperative result showed the patients in staged-HCR group took advantages in less postoperative mechanical ventilation time [Staged-HCR group (11.2±8.7) h vs. BITA group (18.3±9.1) h, P=0.013], shorter domiciling duration in ICU [Staged-HCR group (26.29±4.05) h vs. BITA group (44.74±28.75) h, P=0.022], and less total drainage [Staged-HCR group (695.57±250.46) mL vs. BITA group (1 103.26±547.44) mL, P=0.03] than the patients in the group of minimally invasive total arterial revascularization with BITA. Postoperative in hospital coronary angiography showed satisfactory graft patency rates in both groups [97.5% in Staged-HCR group vs. 97.8% in BITA group]. No MACCE occurred in both groups during hospitalization.

CONCLUSION

Staged-HCR is a feasible method for the treatment of multi-vessel revascularization involving right coronary artery. Minimally coronary revascularization with BITA is associated with superior long-term graft patency and it's recommended for patients who could not tolerate dual-antiplatelet therapy. This study shows that both minimally invasive surgical approaches are safe and effective for treatment of patients with multi-vessel coronary artery disease.

Architecture and Transport Properties of Multifilamentary MgB2 Strands for MRI and Low AC Loss Applications

Standard in-situ type MgB2 strands manufactured by Hyper Tech Inc have 19 - 36 subelements, a monel outer sheath, and a Cu interfilamentary matrix. Typical transport Jc s of the strands are 2×105 A/cm2 with n-values of 20 - 30 at 4.2 K and 5 T. This work introduces two new MgB2 conductor designs. First, a new class of MgB2 strand is designed for magnetic resonance imaging applications. This type has a higher Cu content designed to enhance protection of a magnet wound with it, and a larger diameter to increase the critical current. Second, a new class of low AC loss MgB2 strand with high filament count and a high resistance matrix is discussed. Transport properties at 4.2 K and fields up to 10 T are reported. Optical techniques are used to study the macro- and micro-structures of these MgB2 strands.

Identification of the crucial genes in the elimination and survival process of Salmonella enterica ser. Pullorum in the chicken spleen

Salmonella enterica ser. Pullorum is one of the most easily re-infecting pathogens in poultry production because of its mechanism of escaping from immune elimination. We used the transcriptome method to investigate the variation in gene expression in chicken spleen resulting from the interaction between hosts and S. Pullorum in the survival process. The expression of various genes related to the maturation and activation of B cells was activated before S. Pullorum was eliminated, which might help S. Pullorum escape from the elimination process. The suppression of some genes involved in the fusion of autophagosomes and lysosomes, such as MYO6, was identified and may be regulated by the secretion systems of S. Pullorum. In addition, a large proportion of these differentially expressed genes could be localized in the identified quantitative trait loci regions associated with the antibody response to bacteria. Collectively, these identified genes provided an outline for further understanding the interaction between chicken immune cells and S. Pullorum in chicken spleen.

DTC chemotherapy regimen is associated with higher incidence of premature ovarian failure in women of reproductive age with breast cancer

OBJECTIVE

Different chemotherapy regimens may contribute differently to the development of Premature Ovarian Failure (POF) in women of reproductive age with breast cancer. Here we evaluated how two different chemotherapy regimens, CAF (tegafur + pirarubicin + ifosfamide) and DTC (docetaxel + pirarubicin + ifosfamide), affect the development of POF.

PATIENTS AND METHODS

We enrolled 164 women of reproductive age with breast cancer (mean ± SD age of 34.56 ± 9.48 years). The patients were divided into two groups, which were respectively treated with CAF (n = 89) or DTC (n = 75) chemotherapy regimen. Both study groups were comparable in all analyzed characteristics at baseline. Patients were treated with respective chemotherapy regimen for 6 months and followed up for over 12 months after completion of chemotherapy. Study outcomes were occurrence rates of POF, menstrual status and recovery after completion of chemotherapy, and serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), and oestradiol (E2).

RESULTS

At 6 months after completion of chemotherapy, POF incidence rates were significantly lower in the CAF group. Furthermore, the proportion of patients with eumenorrhea, menstrual disorders or chemotherapy-induced amenorrhea in this study group was also significantly different from the DTC group. Similarly, adverse changes of serum levels of FSH, LH and E2 were less pronounced in the CAF group.

CONCLUSIONS

Both tested chemotherapy regimens can cause POF; however, adverse effects of DCT chemotherapy regimen on ovarian function are more pronounced than those by CAF chemotherapy regimen.

Single nucleotide polymorphism screening, molecular characterization, and evolutionary aspects of chicken Piwi genes

The P-element-induced wimpy testis (Piwi) gene is involved in germline stem cell self-renewal, meiosis, RNA silencing, and transcriptional regulation. Piwi genes are relatively well conserved in many species, but their function in poultry species is unclear. In this study, Piwi genes were sequenced using a target-sequence capture assay in quail and 28 breeds of chicken. Single nucleotide polymorphisms (SNPs) and evolutionary aspects of these chicken breeds were then analyzed. We found that SNP sites existed mainly in the introns of a few chicken breeds, and we selected an SNP on intron 4 for further verification by Sanger sequencing, the results of which were similar to those obtained by the target-capture sequencing assay. The evolutionary analysis revealed that there were more mutations in the Chahua and Leghorn breeds than in the other breeds, and that the phylogenetic tree was divided into four main categories that suggested that Piwi is evolutionarily conserved, and mutations in the introns might be associated with gametogenesis. The screened SNPs can be used as candidate markers for Piwi, and our results provide basic information for the further study of Piwi function in poultry.

Fertility clinicians and infertile patients in China have different preferences in fertility care

STUDY QUESTION

Do the preferences for fertility care of infertile Chinese patients differ from those of fertility care providers?

SUMMARY ANSWER

Infertile Chinese patients attached the greatest importance to physicians' attitude but, in contrast, fertility care providers in China considered treatment effectiveness to be the most important factor in fertility care.

WHAT IS KNOWN ALREADY

In Europe, physicians underestimate the importance of patient-centred infertility care.

STUDY DESIGN, SIZE, DURATION

A conjoint survey was distributed among 417 female infertile Chinese patients and 83 fertility care providers from February 2013 to August 2013.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In this pilot study, 389 patients and 83 fertility care providers completed the survey at three reproductive medicine centres. Rating-based conjoint analysis was performed to elicit patients' and their caregivers' preferences regarding fertility care. Cluster analysis was used to explore the heterogeneity among patients' preferences.

MAIN RESULTS AND THE ROLE OF CHANCE

When searching for fertility care, patients valued the physicians' attitude the most, followed by success rates, distance from home to the fertility centre, physician continuity throughout the treatment period and type of fertility centre. Fertility care providers considered success rates (effectiveness) to be the most important factor when recommending a fertility centre. Fertility patients and care providers had significantly different views on the value of treatment effectiveness, physician attitude and physician continuity (P-values <0.05). Cluster analysis revealed that patients' preferences were heterogeneous.

LIMITATIONS, REASONS FOR CAUTION

The sample size is relatively small, and there is insufficient power for heterogeneity analysis. Two levels for each of five design factors (2(5)) may not fully capture the characteristics of realistic fertility centres. Rating-based conjoint analysis could be inferior to choice-based conjoint analysis in terms of predictive accuracy.

WIDER IMPLICATIONS OF THE FINDINGS

Fertility care providers in China significantly underestimate the importance of patient-centredness to infertile patients. To deliver optimal fertility care to infertile Chinese patients, fertility care providers need to understand the importance of patient-centred care, such as a friendly attitude, sympathy for patients' suffering, respect for patients' right to informed consent and a transparent treatment process.

STUDY FUNDING/COMPETING INTEREST(S)

This study was not funded, and there are no conflicts of interest.

TRIAL REGISTRATION NUMBER

None.

Comparison of three lymph node staging schemes for predicting outcome in patients with gastric cancer

BACKGROUND

Several node staging schemes have been proposed for gastric cancer. The optimal system remains controversial.

METHODS

Patients with gastric cancer were identified from the Surveillance, Epidemiology, and End Results (SEER) database, and a Chinese patient cohort was used for independent validation. The prognostic performance of three node staging schemes was compared, involving a number-based scheme (pN), ratio-based scheme (rN) and log odds of positive lymph nodes scheme (LODDS).

RESULTS

There were 12 443 patients in the SEER database and 866 in the Chinese cohort. LODDS provided better discriminatory capacity and higher predictive accuracy than either pN or rN, for patients with gastric cancer in both the SEER database and the Chinese cohort. The multivariable model using the LODDS classification was significantly more predictive than the pN classification. LODDS suffered much less from stage migration and was able efficiently to discriminate the heterogeneity for patients with no nodes involved or all nodes involved, whereas the pN and rN schemes could not.

CONCLUSION

LODDS showed a clear prognostic superiority over both pN and rN schemes. It could serve as an important reference for the tumour node metastasis (TNM) node classification.

Cigarette smoke exposure hinders long-term allograft survival by suppressing indoleamine 2, 3-dioxygenase expression

Cigarette smoke causes cancer and increases the vulnerability of smokers to infections. Epidemiologic studies have shown that smoking is one of major risk factors for late allograft rejection. Despite statistical data that associate smoking with allograft rejection, no any study has been conducted to prove that cigarette smoke directly causes allograft rejection in a cause-effect manner. In particular, investigation into immunologic mechanisms underlying smoke-related allograft rejection is lacking. Here we found that second hand smoke (SHS) hindered long-term islet allograft survival induced by CD154 costimulatory blockade plus donor-specific splenocyte transfusion (DST), although it failed to alter acute islet allograft rejection. SHS did not directly interfere with vigorously alloreactive T-cell proliferation in vivo and in vitro. Neither naturally occurring nor induced CD4+CD25+ Treg cell numbers were significantly reduced by SHS. However, SHS suppressed mRNA and protein expression of indoleamine 2, 3-dioxygenase (IDO) and its activity upon transplantation while IDO overexpression in islet allografts restored their long-term survival induced by CD154 blockade. Therefore, SHS prevents long-term allograft survival by inhibiting IDO expression and activity. Thus, our study for the first time demonstrates that SHS shortens allograft survival in a cause-effect manner and unveils a novel immunologic mechanism underlying smoking-related allograft rejection.

Factors predicting the cumulative outcome of IVF/ICSI treatment: a multivariable analysis of 2450 patients

BACKGROUND

Knowing predictors of pregnancy in IVF is helpful for clinicians to individualize the treatment plans and improve patient counseling and for patients to decide whether to undergo infertility treatment. The aim of the study was to identify independent predictors of the chance of clinical pregnancy after a completed IVF/ICSI cycle (fresh plus cryopreserved embryos transferred from one stimulated cycle) and to compare the predictive value of important predictors identified.

METHODS

This was a single center, retrospective study of 2450 infertile women undergoing their first IVF treatment between 2002 and 2007. A bootstrapping stepwise variable selection algorithm was performed to identify independent predictors of clinical pregnancy chance from a list of 27 candidate variables. Multivariable logistic regression was used for assessing the effects of predictors. Proportion of explained variation analysis and concordance index were adopted to compare the predictive value of factors.

RESULTS

The following nine independent predictors were included in the final multivariable model: total number of good-quality embryos, total number of embryos, age, antral follicle count, fertilization rate, duration of infertility, endometrial thickness, number of 10-14-mm follicles and progesterone level on the day of hCG injection. The model was cross-validated internally in the training data and validated externally in an independent data with robust performance. The stratified analysis demonstrated that the total number of good-quality embryos was a better predictor of clinical pregnancy chance after a completed IVF/ICSI cycle than age for women <40 years, whereas age was a better predictor for women ≥ 40 years. The restricted cubic spline analysis revealed the relationship between the total number of good-quality embryos and log-odds of achieving a clinical pregnancy was nonlinear.

CONCLUSIONS

Quality and quantity of the whole embryos are the two most important predictors of the cumulative outcome in IVF/ICSI among independent predictors indentified. The importance of embryo quality on cumulative outcome in IVF/ICSI increases with increasing age.

The amount of surface HLA-I on T lymphocytes decreases in breast infiltrating ductal carcinoma patients

Human leucocyte antigen class I (HLA-I), which includes HLA-A, -B and -C, is an essential immune factor participating in the antitumour immune response. The changes in HLA-I expression in peripheral blood T lymphocytes in cancer patients have yet to be defined. This study examined the expression of HLA-I on CD4(+) and CD8(+) T lymphocytes in female patients with stage I - IV breast infiltrating ductal carcinoma, benign breast tumour diseases (mammary intraductal papilloma or breast fibroadenoma), and in healthy controls. HLA-I was down-regulated on CD4(+) T lymphocytes from patients with stage III and IV cancer, and on CD8(+) T lymphocytes in patients with stage I - IV cancer compared with healthy controls. HLA-I expression in T lymphocytes may contribute towards immune-balance disorders in tumour patients.

Autologous carotid artery reconstruction for the extracranial internal carotid artery aneurysm in a patient combined with pulmonary bulla

INTRODUCTION

Aneurysm of the extracranial internal carotid artery (AEICA) is extremely rare catastrophic pathology associated with cerebral embolism and rupture. There was no report on AEICA associated with bullous lung disease.

REPORT

We report a case of AECIA in a 44-year-old female patient combined with asymptomatic pulmonary bulla, and successfully treated by autologous carotid artery reconstruction.

CONCLUSION

The possibility of a relationship between AEICA and bullous lung disease is discussed about the level of alpha 1-antitrypsin (α1-AT). The using of external carotid artery (ECA) replace of the internal carotid artery (ICA) combined with resection of the AEICA is an autologous reconstruction to restore arterial continuity and avoiding the use of synthetic or vein graft with their potential complications.

Identification of craniofacial risk factors for obstructive sleep apnoea using three-dimensional MRI

The alteration of craniofacial structures has been associated with obstructive sleep apnoea (OSA). We hypothesised that: 1) a smaller mandible is a risk factor for OSA; and 2) the previously observed inferiorly positioned hyoid bone in apnoeics is associated with enlarged tongue volume. This is a case-control study using three-dimensional magnetic resonance imaging cephalometry. 55 apneics and 55 controls were matched for age, sex and race. The analysis was stratified by sex and controlled for age, race, height, neck visceral fat, skeletal type and tongue volume. We found that a 1-sd increase in mandibular length and depth were associated with decreased risk of sleep apnoea (OR 0.52, 95% CI 0.28-0.99 and OR 0.46, 95% CI 0.23-0.91, respectively) in males but not in females. Greater hyoid-to-nasion (OR 2.64, 95% CI 1.19-5.89 in males and OR 5.01, 95% CI 2.00-12.52 in females) and supramentale-to-hyoid (OR 2.39, 95% CI 1.12-5.14) in males and OR 3.38, 95% CI 1.49-7.68 in females) distances were associated with increased risk of OSA. The difference for hyoid position between apnoeics and controls was lost after controlling for tongue volume. Enlargement of tongue is likely to be the pathogenic factor for inferior-posterior positioning of hyoid. A small and shallow mandible is an independent risk factor for OSA in males but not in females.

Off-pump coronary artery bypass graft surgery: a training course for novices and its learning curve

BACKGROUND

The learning curve for off-pump coronary artery bypass grafting (OPCABG) surgery still requires further discussion. Training programs aimed at the conversion of conventional coronary artery bypass grafting (CABG) to OPCABG have mainly been geared towards those persons who already have much experience in conventional CABG. The goals of this study were to retrospectively analyze the training process of two trainees who had no previous coronary surgery experience and to discuss the efficiency and feasibility of the training.

METHODS

Two cardiac surgeons were enrolled in this study; they had different surgical backgrounds but neither had ever previously performed coronary surgery. They were trained to become independent surgeons capable of performing OPCABG procedures by a supervising surgeon who had performed more than 2 000 OPCABG surgeries. Clinical data were collected from each trainee subject's first 100 cases of OPCABG surgery and grouped according to the following scheme: Group A (1) (Doctor A's first 50 cases), Group A (2) (Doctor A's second 50 cases), Group B (1) (Doctor B's first 50 cases) and Group B (2) (Doctor B's second 50 cases). A consecutive series of 50 cases of OPCABG surgery performed by the supervising surgeon served as the control group (Group C). Cumulative sum failure analysis for each subject was used to complete the learning curve study.

RESULTS

The training time was 28 months for Doctor A and 24 months for Doctor B; the difference in training time was presumably due to their different surgical backgrounds. Among the cases in Group A (1), Group A (2) and Group B (1), there were fewer distal anastamoses, fewer sequential grafts, and less marginal branch grafting in the left circumflex artery than in the Group C cases. Operating times and ICU stay were longer in Group A (1) than in Group C. There were no group differences with regard to total mortality or the incidence of complications. CUSUM analysis showed that the curves of the two trainees had a small steep elevation during the first 30 cases, and proceeded smoothly thereafter, never passing the 80 % alert lines.

CONCLUSIONS

The appropriate qualifications for OPCABG trainees and the optimal OPCABG training program have not yet been resolved. In this study, the observed learning curves of cardiac surgeons who had no prior coronary surgery experience during their training to perform the OPCABG procedure by a sophisticated OPCABG surgeon indicated that the training program employed was feasible and its outcomes were reasonable.