Weak-link Josephson Junctions Made from Topological Crystalline Insulators.

We report on the fabrication of Josephson junctions using the topological crystalline insulator Pb_{0.5}Sn_{0.5}Te as the weak link. The properties of these junctions are characterized and compared to those fabricated with weak links of PbTe, a similar material yet topologically trivial. Most striking is the difference in the ac Josephson effect: junctions made with Pb_{0.5}Sn_{0.5}Te exhibit a rich subharmonic structure consistent with a skewed current-phase relation. This structure is absent in junctions fabricated from PbTe. A discussion is given on the origin of this effect as an indication of novel behavior arising from the topologically nontrivial surface state.

Influence of storage time on DNA of Chlamydia trachomatis, Ureaplasma urealyticum, and Neisseria gonorrhoeae for accurate detection by quantitative real-time polymerase chain reaction.

The shipment and storage conditions of clinical samples pose a major challenge to the detection accuracy of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Ureaplasma urealyticum (UU) when using quantitative real-time polymerase chain reaction (qRT-PCR). The aim of the present study was to explore the influence of storage time at 4°C on the DNA of these pathogens and its effect on their detection by qRT-PCR. CT, NG, and UU positive genital swabs from 70 patients were collected, and DNA of all samples were extracted and divided into eight aliquots. One aliquot was immediately analyzed with qRT-PCR to assess the initial pathogen load, whereas the remaining samples were stored at 4°C and analyzed after 1, 2, 3, 7, 14, 21, and 28 days. No significant differences in CT, NG, and UU DNA loads were observed between baseline (day 0) and the subsequent time points (days 1, 2, 3, 7, 14, 21, and 28) in any of the 70 samples. Although a slight increase in DNA levels was observed at day 28 compared to day 0, paired sample t-test results revealed no significant differences between the mean DNA levels at different time points following storage at 4°C (all P>0.05). Overall, the CT, UU, and NG DNA loads from all genital swab samples were stable at 4°C over a 28-day period.

DNA methylation profiles in placenta and its association with gestational diabetes mellitus.

Emerging evidences indicate that placenta plays a critical role in gestational diabetes mellitus (GDM). DNA methylation could be associated with altered placental development and functions. This study is to uncover the genome-wide DNA methylation patterns in this disorder. DNA methylation was measured at >385,000 CpG sites using methylated DNA immunoprecipitation (MeDIP) and a huamn CpG island plus promoter microarray. We totally identified 6,641 differentially methylated regions (DMRs) targeting 3,320 genes, of which 2,729 DMRs targeting 1,399 genes, showed significant hypermethylation in GDM relative to the controls, whereas 3,912 DMRs targeting 1,970 genes showed significant hypomethylation. Functional analysis divided these genes into different functional networks, which mainly involved in the pathways of cell growth and death regulation, immune and inflammatory response and nervous system development. In addition, the methylation profiles and expressions of 4 loci (RBP4, GLUT3, Resistin and PPARα) were validated by BSP for their higher log2 ratio and potential functions with energy metabolism. This study demonstrates aberrant patterns of DNA methylation in GDM which may be involved in the pathophysiology of GDM and reflect the fetal development. Future work will assess the potential prognostic and therapeutic value for these findings in GDM.

Association of maternal KIR and fetal HLA-C genes with the risk of preeclampsia in the Chinese Han population.

INTRODUCTION: This study is to investigate the distribution of inhibitory and activating killer-cell immunoglobulin-like receptors (KIRs) and the combination of KIR/human leukocyte antigen (HLA)-C in women with preeclampsia in the Chinese Han population. METHODS: A total of 271 patients and 295 controls were enrolled in our study. The inhibitory/activating KIR and HLA-C genes were detected using the PCR-SSP (polymerase chain reaction with sequence-specific primers) method. RESULTS: Our result showed that decreased numbers of individual activating KIR genes (2DS2, 2DS3, and 2DS5) were observed in women with preeclampsia. Furthermore, the gene frequency of total activating KIRs was significantly lower in patients compared with that of the controls (P = 0.03). The frequency of the KIR2DL1 gene was increased in women with preeclampsia when a homozygous HLA-C2 allele appeared in the fetus. CONCLUSION: The results suggest that a KIR genetic variation might influence the risk of preeclampsia. The lack of activating KIRs could possibly lower uterine natural killer (uNK) cell activation, thereby contributing to the pathogenesis of preeclampsia. Moreover, the imbalance of the inhibitory or activating signals at the maternal-fetal interface seems to play a regulatory role in the occurrence of preeclampsia.

Pretransplant IgG reactivity to apoptotic cells correlates with late kidney allograft loss.

Preexisting serum antibodies have long been associated with graft loss in transplant recipients. While most studies have focused on HLA-specific antibodies, the contribution of non-HLA-reactive antibodies has been largely overlooked. We have recently characterized mAbs secreted by B cell clones derived from kidney allograft recipients with rejection that bind to apoptotic cells. Here, we assessed the presence of such antibodies in pretransplant serum from 300 kidney transplant recipients and examined their contribution to the graft outcomes. Kaplan-Meier survival analysis revealed that patients with high pretransplant IgG reactivity to apoptotic cells had a significantly increased rate of late graft loss. The effect was only apparent after approximately 1 year posttransplant. Moreover, the association between pretransplant IgG reactivity to apoptotic cells and graft loss was still significant after excluding patients with high reactivity to HLA. This reactivity was almost exclusively mediated by IgG1 and IgG3 with complement fixing and activating properties. Overall, our findings support the view that IgG reactive to apoptotic cells contribute to presensitization. Taking these antibodies into consideration alongside anti-HLA antibodies during candidate evaluation would likely improve the transplant risk assessment.

Association of HLA-DRB alleles and pulmonary tuberculosis in North Chinese patients.

Human leukocyte antigen (HLA) plays a central role in the regulation of the immune response. HLA class II molecules are essential for T cell-mediated adaptive immunity and present peptide antigens to CD4(+) T cells. Because of its important role in the immune response and its high degree of polymorphism, the HLA system is associated with many diseases. We examined the polymorphisms of HLA-DRB alleles and the sequences of the HLA-DRB promoter region in 97 unrelated patients with pulmonary tuberculosis and in 62 unrelated normal controls of the Han nationality from North China, using PCR with sequence-specific primers and PCR direct sequencing. We found that the frequency of HLA-DRB1*15 was significantly higher in the pulmonary tuberculosis group than in the healthy control group. The P value was 0.001, and the odds ratio was 3.793. The pulmonary tuberculosis group had the same HLA-DRB1 promoter region sequences as the control group. We concluded that the HLA-DRB1*15 allele is associated with pulmonary tuberculosis in the Han nationality from North China. The HLA-DRB1 promoter region sequences had no association with the development of pulmonary tuberculosis.

Influence of colorectal laparoscopic surgery on dissemination and seeding of tumor cells.

BACKGROUND: This study aimed to compare the influence of colorectal laparoscopic surgery and conventional surgery on dissemination and seeding of tumor cells. METHODS: Intraoperative peritoneal lavage cytology was performed for 36 patients with colorectal cancer during colorectal laparoscopic surgery and for 45 patients with colorectal cancer during conventional surgery. Cytology was examined twice: immediately after opening of the peritoneal cavity and just before closure of the abdomen. Saline was poured into the peritoneal cavity, and 100 ml fluid was retrieved after irrigation. Laparoscopic instruments were lavaged after surgery with 100 ml of saline. Carbon dioxide (CO(2)) was derived through the trocar side orifice after pneumoperitoneum during laparoscopic coloectomy and filtered through 100 ml of saline. Cytologic examination of the filtrate was performed after the filtration process, smear, cell block, and staining. RESULTS: Malignant cells were not detected in the CO(2) filtrate gas. The incidence of positive cytology in the lavage of the instruments during laparoscopic surgery was 2.78%. The incidence of positive cytology during laparoscopic surgery was 33.33% in the prelavage and 8.33% in the postlavage. The incidence of positive cytology during conventional surgery was 33.33% in the prelavage and 11.11% in the postlavage. CONCLUSION: During colorectal laparoscopic surgery, CO(2) pneumoperitoneum does not affect tumor cell dissemination and seeding. In this study, laparoscopic techniques used in colorectal cancer surgery were not associated with a greater risk for intraperitoneal dissemination of cancer cells than the conventional technique.

Optical implementation of the hopfield neural network with matrix gratings.

We propose a new method for the optical implementation of the Hopfield neural network with a universal tool. The tool is a matrix grating constituted with a group of element gratings. The algorithms for designing a matrix grating are proposed, and a matrix grating is created to execute recognition experiments by use of the Hopfield neural network. The experimental results demonstrate that the proposed method performs well. The stability of the light efficiencies of different optical components used in optical networks is also considered.

Treatment of atrophic vaginitis with topical conjugated equine estrogens in postmenopausal Asian women.

OBJECTIVE: We investigated the effects of 2 months of treatment with topical estrogens on atrophic vaginitis and gynecological health in Asian women. STUDY DESIGN: Multicenter, open-label trial of 150 postmenopausal women age <70 years with atrophic vaginitis. Women applied conjugated equine estrogens (CEE) vaginal cream (0.625 mg/g) once daily on days 1-21 of two 28-day cycles. Changes in the vaginal maturation index (VMI) from baseline to days 21 (month 1) and 49 (month 2) were the primary outcome. Physiological changes were assessed by the Genital Health Clinical Examination (GHCE). RESULTS: The VMI was significantly improved (p < 0.001) from baseline at each assessment period. The significant improvement in GHCE from baseline after 1 month (p < 0.001) was maintained at 2 months. CONCLUSIONS: Vaginal treatment with CEE cream for 21 days of two consecutive 28-day cycles resulted in beneficial changes in the vaginal tissues and induced an overall genital health pattern more characteristic of the premenopausal state.