Search

The purpose of this study was to explore the expression pattern of long non-coding RNA (lncRNA) ZFPM2-AS1 in breast cancer (BC) tissues, and its biological influence on clinical features and prognosis in BC patients.ZFPM2-AS1 levels in 52 paired BC tissues and adjacent normal ones were detected. Then, the relationship between ZFPM2-AS1 level and clinical features in BC patients was analyzed. Regulatory effects of ZFPM2-AS1 on proliferative and migratory abilities in MCF-7 and SKBR3 cells were assessed. In addition, in vivo regulation of ZFPM2-AS1 in nude mice bearing BC was evaluated. Finally, the interaction between ZFPM2-AS1 and JMJD6 and the involvement of ZFPM2-AS1 in the development of BC were illustrated.The results showed that ZFPM2-AS1 was upregulated in BC tissues, and its high level was linked to advanced tumor stage, high rates of lymphatic metastasis, and distant metastasis, as well as poor prognosis in BC. The knockdown of ZFPM2-AS1 suppressed proliferative and migratory abilities in BC cells. In addition, JMJD6 was verified to be the downstream gene binding to ZFPM2-AS1, which was highly expressed in BC tissues and positively regulated by ZFPM2-AS1. In vivo knockdown of ZFPM2-AS1 in nude mice bearing BC showed a smaller tumor volume and lower tumor weight than controls. In addition, JMJD6 was downregulated in BC tumors extracted from mice with silenced ZFPM2-AS1.LncRNA ZFPM2-AS1 is upregulated in BC and linked to tumor stage, metastasis, and prognosis in BC patients. It aggravates the malignant development of BC via upregulating JMJD6.

The purpose of this study was to compare the differences of degenerative characteristics of medial, lateral regions, femoral, patellar, and tibia parts of the knee joint in the early stage of knee osteoarthritis (OA).A total of 66 patients with early-stage knee OA and 22 healthy volunteers who have no knee-related clinical symptoms were enrolled in this cross-sectional study. T2 mapping and 3D dual-echo images were acquired with a 3.0T MR scanner. The degenerative changes of the articular cartilage were quantified by a T2 mapping and cartilage thicknesses analysis. Any structural changes were conducted using the Whole Organ Magnetic Resonance Imaging Score (WORMS).In patients with knee OA, the thicknesses of medial cartilages were significantly thinner than lateral ones (2.13 mm vs. 2.34 mm, p0.0001), but with higher T2 values (40.38 ms vs. 38.4 ms, p0.0001) and WORMS scores (12.12 vs. 0.47, p=0.004). No significant differences were observed between medial and lateral cartilage in the healthy volunteers. The T2 values of the femoral (p0.001) and patellar (p=0.012) cartilages of OA patients were higher than that of the healthy controls. Within OA group, the T2 values of femoral (p0.0001) and patellar (p0.0001) cartilages were higher than tibial ones. Moreover, the WORMS scores of femoral (p=0.001) and patellar (p0.0001) cartilages were higher than that of the tibial ones.This study demonstrates that the medial compartment and patellofemoral knee joint degenerate more severely in patients with early-stage knee OA.

T helper 17 (Th17) cells are involved in the pathogenesis of multiple sclerosis (MS). The present study aimed to explore the role of miR-1-3p in Th17 cell differentiation associated with MS. PATIENTS AND METHODS: Expression of miR-1-3p in periphery blood mononuclear cells (PBMC), cerebrospinal fluid (CSF), CD4+ T cells, CD8+ T cells, non-T cells and differentiated CD4+ T cells derived from healthy donors and MS patients during remitted and relapsed stages was detected. Level of ETS1 in PBMC in MS-relapse patients was examined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Correlations among neurofilament light (NF-L), C-reactive protein (CRP), estrogen receptor 1 (ESR), interleukin 17A (IL-17A) in serum, NF-L, C-X-C motif chemokine ligand 13 (CXCL13), chitinase 3 like 1 (CHI3L1), RAR related orphan receptor C (RORC) in CSF, and ETS proto-oncogene 1 (ETS1), RORC in PBMC and miR-1-3p expression were analyzed. The target gene of miR-1-3p was analyzed by performing Dual-Luciferase reporter assay, and the IL-17A+ CD4+ (Th17) cells were detected by flow cytometer. Gene expressions of IL-17A, RORC and Th17 pathogenic were determined by qRT-PCR.Upregulated miR-1-3p was observed in MS-relapse patients and Th17 cells, and expression of miR-1-3p was positively correlated with MS severity. MiR-1-3p overexpression in naïve CD4+ T cells promoted the differentiation of Th17 cells by upregulating the level of inflammation-associated markers. The expression of ETS1, which was predicted to be the target gene of miR-1-3p, was reduced in PBMC from MS-relapse patients, while the upregulation of ETS1 inhibited the expression of pathogenic genes of Th17.The study demonstrated the positive role of miR-1-3p in Th17 differentiation associated with MS via targeting ETS1.

To investigate the expression of LINC00472 in osteoporotic issues of patients, ovariectomized (OVX) mice and mice bone marrow mesenchymal stem cells (BMSCs), its effect on osteogenic differentiation of BMSCs and its mechanism.The expression of LINC00472 and miR-300 in osteoporosis patients (n=55), ovariectomized (OVX) mice (n=10) and mice BMSCs (n=3) was detected by RT-qPCR and the correlation between the expression of miR-300 and LINC00472 was analyzed. After transferring sh-LINC00472 and overexpression LINC00472 plasmids into mice BMSCs, the expression of ALP, Bglap, OPN, Runx2 was detected by RT-qPCR and Western blot, which were related with osteogenic differentiation. In addition, Luciferase activity was used to detect whether miR-300 combined with LINC00472 and FGFR2 in mice BMSCs directly. Finally, Western blot (WB) was used to detect the change of FGFR2 protein expression by miR-300 inhibitor and sh-LINC00472.We found there was a negative correlation between the expression of miR-300 and LINC00472 in osteoporosis patients, bone tissues of OVX mice and mice BMSCs. The expression of LINC00472 in mice BMSCs was gradually increased with osteogenic differentiation. Transferring overexpression plasmid of LINC00472 into BMSCs, the expression of ALP, Bglap, OPN, Runx2 was increased both in mRNA and protein levels. Transferring sh-LINC00472 to BMSCs, the results were the opposite. Luciferase results showed that miR-300 could directly bind to LINC00472 and FGFR2 in mice BMSCs. What's more, RT-qPCR and WB results showed that transferring sh-LINC00472 could decrease the expression of FGFR2 mRNA and protein, while miR-300 inhibitor could recover this tendency.According to these results, this study revealed the previously neglected LINC00472/miR-300/FGFR2 regulatory axis for the regulation of osteogenic differentiation in osteoporosis, which may be a potential target for the treatment of osteoporosis.

Emerging evidences suggest that necrosis is programmed and is one of the main forms of cell death in the pathological process in cardiac diseases. Long noncoding RNAs (lncRNAs) are emerging as new players in gene regulation. However, it is not yet clear whether lncRNAs can regulate necrosis in cardiomyocytes. Here, we report that a long noncoding RNA, named necrosis-related factor (NRF), regulates cardiomyocytes necrosis by targeting miR-873 and RIPK1 (receptor-interacting serine/threonine-protein kinase 1)/RIPK3 (receptor-interacting serine/threonine-protein kinase 3). Our results show that RIPK1 and RIPK3 participate in H2O2-induced cardiomyocytes necrosis. miR-873 suppresses the translation of RIPK1/RIPK3 and inhibits RIPK1/RIPK3-mediated necrotic cell death in cardiomyocytes. miR-873 reduces myocardial infarct size upon ischemia/reperfusion (I/R) injury in the animal model. In exploring the molecular mechanism by which miR-873 expression is regulated, we identify NRF as an endogenous sponge RNA and repress miR-873 expression. NRF directly binds to miR-873 and regulates RIPK1/RIPK3 expression and necrosis. Knockdown of NRF antagonizes necrosis in cardiomyocytes and reduces necrosis and myocardial infarction upon I/R injury. Further, we identify that p53 transcriptionally activates NRF expression. P53 regulates cardiomyocytes necrosis and myocardial I/R injury through NRF and miR-873.Our results identify a novel mechanism involving NRF and miR-873 in regulating programmed necrosis in the heart and suggest a potential therapeutic avenue for cardiovascular diseases.

By first-principle study, we propose a possible stable helium-based compound with chemical formula of Na2HeO. It has a structure of space group [Formula: see text]. Energy calculation indicates that it has a local minimum with a lattice constant [Formula: see text] Å. Electronic band structure suggests that it is a wide gap insulator. Analysis on Hirshfeld charges and charge density distribution shows a chemical bond formed between O and He atoms in this structure. Results from both elastic constants and phonon dispersion indicate that this compound in the proposed structure is both mechanically and dynamically stable.

In order to study the insulation performance of two retired high voltage cross-linked polyethylene (XLPE) cables with service years of 16 and 32 and evaluate the reliability of reusing these cables for actual operation, a 180-day electro-thermal aging test was exerted on a section of these two cables to inspect the changes on structural and electrical properties. Several diagnostic measurements including fourier infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and breakdown field strength were carried out on the untreated and treated samples. The measured results show that the crystalline structure of the 16 years cable has been improved after the accelerated aging test probably because of the reduction of the impurities and the annealing effect, which further improve the electrical property. Even though the molecular chains of the 32 years cable insulation has been damaged and a slight degradation happens on the crystalline structure under the intensive aging test condition, which is responsible for the decline in the electrical property, the cable still have the potential to resist the stresses properly under the actual operation condition for a long time from the perspective of the XLPE. Therefore, it can be expected that the rest of these two retired cables still have the ability to reuse in the long-term actual operation condition.

In pursuit of lightweighting of automobiles and low emission of transportation, the efforts to develop high-strength, heat-resistant and fatigue-resistant Al alloys and/or composites have been ongoing. Here we report a novel Al matrix composite with ultrahigh strength reinforced by a three dimensional network of nano-AlN particles for the first time. The in-situ synthesized AlN particles are connected by twinning bonding chains and built up a three dimensional network strengthening Al matrix enormously like the skeleton to human body. The composite containing 16.4wt.% AlN particles shows excellent properties: the ultimate tensile strengths can be up to 518MPa at room temperature and 190MPa at 350 °C. This peculiar performance results from the novel spatial distribution of nano-scale AlN particles. Our findings in this work would help to develop a potential candidate for high-performance heat resistance light-metal based materials.

To evaluate the diagnostic performance of bi-exponential modeling of intravoxel incoherent motion (IVIM) imaging for laryngeal and hypopharyngeal carcinoma.A total of 32 patients with pathologically proven laryngeal and hypopharyngeal squamous cell carcinoma were included in this study from November 2014 to August 2015.All patients underwent IVIM-DWI by using twelve b values (0, 10, 20, 30, 50, 70, 100, 150, 200, 400, 800 and 1 000 s/mm(2)). Using the IVIM approach, D, D(*) and f values were extracted using a bi-exponential fit.These quantitative parameters of primary carcinoma and normal pharyngeal tissue were compared.Statistical methods were used to assess differences between the tumor and normal pharyngeal tissue.There were no significant differences of D (P=0.903) and f (P=0.223) values observed among laryngeal carcinoma and hypopharyngeal carcinoma, and D(*) value was significantly different among the two groups (P=0.028). The values of D, D(*,) and f for primary carcinoma were (0.84±0.22)×10(-3) mm(2)/s, (65.71±19.66)×10(-3) mm(2)/s, and 45%±14%, respectively; for normal pharyngeal tissue were (1.48±1.04)×10(-3) mm(2)/s, (37.85±14.04)×10(-3) mm(2)/s, and 36%±12%, respectively (P=0.001, 0.000, and 0.006, respectively). Setting D value 0.949×10(-3) mm(2)/s was threshold to distinguish abnormal and normal tissues, the sensitivity, specificity and accuracy were 91.2%, 88.2% and 92.5%, respectively.There was no statistically significant difference of D and f values(both P0.05)in different pathological grades of primary carcinoma, and there was statistically significant difference in D(*) values found among the different pathological grades of primary carcinoma (P=0.001). There were statistically significant differences in D(*) values between the well differentiated group and the other two group (both P0.05), and there was no statistically significant difference between the moderately differentiated group and poorly differentiated group (P0.05).IVIM parameters can reflect the difference between laryngeal and hypopharyngeal carcinoma and normal pharyngeal tissue, and the D value has the best diagnostic performance.D(*) value in different pathological grades of laryngeal and hypopharyngeal squamous cell carcinoma is distinct, and it could reflect the pathological grade of tumor to some extent.

We report a new measurement of electron antineutrino disappearance using the fully-constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9$\times$10$^5$ GW$_{\rm th}$-ton-days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six $^{241}$Am-$^{13}$C radioactive calibration sources reduced the background by a factor of two for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of $\sin^{2}2\theta_{13}$ and $|\Delta m^2_{ee}|$ were halved as a result of these improvements. Analysis of the relative antineutrino rates and energy spectra between detectors gave $\sin^{2}2\theta_{13} = 0.084\pm0.005$ and $|\Delta m^{2}_{ee}|= (2.42\pm0.11) \times 10^{-3}$ eV$^2$ in the three-neutrino framework., Comment: Updated to match final published version

Bone marrow-derived mesenchymal stem cells (MSCs) can serve as a vehicle for gene therapy. FGF2 (basic fibroblast growth factor) is a multifunctional growth factor and exhibits diverse function in different cell types, it also has pleiotropic effects in different tissues and organs, including potent angiogenic effects and an important role in the differentiation and function of the central nervous system. We hypothesized that MSC-based FGF2 gene therapy might be a potential therapeutic approach for lipopolysaccharide (LPS)-induced lung injury.MSCs were isolated from 6 week-old inbred male mice and transduced with the FGF2 gene, using a lentivirus vector.In the in vivo mouse model, the LPS-induced lung injury was markedly alleviated in the group treated with MSCs carrying FGF2 (MSCs-FGF2), compared with groups treated with MSCs alone. The histopathological index of LPS-induced lung injury was improved after MSCs-based FGF2 gene treatment. The MSCs-FGF2 administration also reduced the level of inflammatory cytokines.These results suggest that MSCs and FGF2 have a synergistic role in the treatment of LPS-induced lung injury.

The effects of vertical compressive stress on Sb2Te3 nano-films have been investigated by the first principles calculation, including stability, electronic structure, crystal structure, and bond order. It is found that the band gap of nano-film is sensitive to the stress in Sb2Te3 nano-film and the critical thickness increases under compressive stress. The band gap and band order of Sb2Te3 film has been affected collectively by the surface and internal crystal structures, the contraction ratio between surface bond length of nano-film and the corresponding bond length of bulk decides the band order of Sb2Te3 film. Published version

In this paper, we introduce p-mapping spaces for p-operator spaces on $L_{p}$ spaces, which can be regarded as p-generalization of mapping spaces for operator spaces. We then apply p-mapping spaces to study the p-local reflexivity for p-operator spaces on $L_{p}$ spaces.

Regular domain boundaries (RDBs) on a Si(111)-7×7 surface are investigated both theoretically and experimentally. Based on the assumption that the RDBs form from a relative shift between two adjacent parts of the perfectly reconstructed lattice, a set of indexes is proposed to classify the RDBs. The irreducible indexes are obtained according to the constraints derived from the lattice-matching condition and the symmetry of the Si(111)-7×7 structure. Along the RDBs, dimer rows should be constructed serving as backbones, and the defects in the RDB should be accompanied by a dimer-adatom stacking fault subunit or unit spanning the RDB as a matching bridge. Most of the RDBs we obtained by direct annealing of the Si(111) surface and through solid phase growth have such features. The atomic structural models compared to the STM images of several examples are presented.

Dissolved oxygen (DO) is closely related to water self-purification capacity. In order to better forecast its concentration, the chaotic prediction model, based on the wavelet transform, is proposed and applied to a certain monitoring section of the Mentougou area of the Haihe River Basin. The result is compared with the simple application of the chaotic prediction model. The study indicates that the new model aligns better with the real data and has a higher accuracy. Therefore, it will provide significant decision support for water protection and water environment treatment.

Secreted Frizzled-related protein 1 (sFRP1), as one of most important Wnt antagonists, is frequently silenced by promoter hypermethylation in many types of tumor, including hepatocellular carcinoma (HCC). In this study, we aimed to investigate whether restoration of sFRP1 affected HCC metastatic behavior. sFRP1 mRNA expression and promoter methylation in HCC tissues and cell lines were examined using RT-PCR and methylation-specific PCR (MS-PCR), respectively. sFRP1 protein expression was assessed by Western Blot. We generated stable HCC cell line restoration of sFRP1 in HepG2 cells, which naturally do not express detectable sFRP1 mRNA. The effects of exogenous sFRP1 on HepG2 cell invasion were investigated using trans-well assay. Also the effects of sFRP1 re-expression on the β-catenin/T-cell factor-dependent transcription activity was measured by luciferase assay.sFRP1 promoter methylation was frequently observed in HCC tissues (60%) and cell lines (75%). All samples with sFRP1 methylation showed down-regulation of sFRP1 expression in HCC cell lines. Demethylation treatment with 5-aza-20-deoxycytidine in HCC cells restored sFRP1 expression. Restoration of sFRP1 substantially impaired the invasive potentials of HepG2 cells. Moreover, exogenous sFRP1 caused significant decrease of β-catenin/T-cell factor-dependent transcription activity.These findings demonstrate that sFRP1 silencing due to promoter hypermethylation is a major event during tumorigenesis. sFRP1 is also a negative modulator of canonical Wnt signaling, which could contribute to metastasis in HCC progression, thus providing a possible therapeutic strategy against HCC.

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field. © 2012 Landes Bioscience.

The epidemiology and effects of functional constipation (FC) on Chinese people remain unclear.To investigate the epidemiology of FC and its distinction from constipation-predominant irritable bowel syndrome (IBS-C) in China.A cross-sectional survey was conducted in a representative adult Chinese population (n = 16,078), which was selected from five regions using randomised, stratified, multistage sampling methodology. All respondents completed the modified Rome II questionnaire; 20% were asked to complete the 36-item Short Form (SF-36) and the Epworth Sleepiness Scale (ESS).Overall, 948 respondents (6%) had FC and FC was more prevalent in women than in men (8% vs. 4%, P0.001). Straining and hard stools were the two most frequent symptoms. FC was associated significantly with dyspepsia and abdominal bloating. All SF-36 domain scores were lower for respondents with FC than for those without. The prevalence of clinically meaningful daytime sleepiness was significantly higher in respondents with FC than in those without (22% vs. 14%, P = 0.003). Respondents with FC were more likely to strain, but less likely to have a feeling of incomplete emptying after a bowel movement than those with IBS-C. Respondents with IBS-C experienced similar demographics, quality of life and daytime sleepiness to those with FC.The prevalence of FC in China is substantially lower than that in Western countries. FC has negative effects on quality of life and daytime sleepiness. The demographics and burden of illness are similar between FC and IBS-C, although the clinical symptoms are somewhat different.

Background: The Sonic hedgehog (SHH) protein produced in the zone of polarising activity (ZPA) is a major determinant of the identity and numbers of digits in early limb development. Preaxial polydactyly types II (PPD2) and III (PPD3) have been mapped to a critical region at 7q36, and subsequently shown to be caused by point mutations in the ZPA regulatory sequence (ZRS), a long range cis-regulator for the SHH gene. Triphalangeal thumb–polysyndactyly syndrome (TPTPS) and syndactyly type IV (SD4) were also mapped to the 7q36 region but pathogenic mutations in ZRS have not yet been affirmed. Methods and results: We performed linkage and haplotype analysis in six Han Chinese families with TPTPS and/or SD4, and refined the disease locus to an interval of 646 kb containing ZRS. In all families, the affected individuals heterozygous at rs10254391 (a single nucleotide polymorphism within ZRS) revealed a remarkable allele imbalance on sequence chromatogram. Using real-time quantitative polymerase chain reaction (qPCR), we identified duplication of ZRS and found that this duplication segregated with the limb phenotypes in all families but was not detected in unaffected family members or in unrelated control individuals. The duplication was also confirmed by interphase fluorescence in situ hybridisation (FISH) in an affected individual. We designed 17 additional qPCR assays and defined the minimum duplications in all six families, ranging from 131kb to 398kb. Conclusion: Both TPTPS and SD4 are due to duplications involving ZRS, the limb specific SHH enhancer. Point mutations in the ZRS and duplications encompassing the ZRS cause distinctive limb phenotypes.

The condensation reactions of sodium trimetaphosphate with single amino acids, namely glycine, L-alanine, beta-alanine and gamma-aminobutyric acid or pairs of these amino acids were reinvestigated by electrospray ion-trap mass spectrometry and high performance liquid chromatography. It was found when mixtures were treated by sodium trimetaphosphate only in the presence of alpha-amino acid dipeptides were formed. Without addition of alpha-amino acids, the beta-amino acid or gamma-aminobutyric acid could not form peptide either by themselves or with their mixtures under the same conditions. From the data it is concluded that phosphate might select alpha-amino acids to produce the peptides being important precursors for the origin of life.

The geometries of the most stable isomers of gold telluride systems AuTe, Au2Te, and AuTe2 are determined using the MP2 method. The aspect of gold—telluride interaction, the electron correlation, and relativistic effects on geometry and stability are investigated at the MP2 and CCSD(T) theoretical levels. The results show that the electron correlation and relativistic effects are responsible not only for gold—gold attraction but also for additional gold—telluride interaction. The gold—telluride interaction is strong enough to modify the known pattern of bare gold clusters. Both effects are essential for determining the geometry and relative stability of this type of systems.

The contents of the article ‘Effect of magnetic relaxation on flux jump in high temperature superconductors’, Eur. Phys. J. B 77, 363 (2010) are retracted from publication by the authors due to admitted plagiarism of unpublished work. T.H. He wishes to state that he was not involved in the publication process and his name was used on the paper without his knowledge. The work reported was performed by Xiaobin Yang and You-He Zhou at the Key Laboratory of Mechanics on Disaster and Environment in Western China Attached to the Ministry of Education of China. Xiaobin Yang and You-He Zhou retain the right to resubmit the work for publication in a journal of their choice.

Numerous tumor cell lines of leukemic origin are known to modulate cell surface expression of major histocompatibility complex (MHC) class I antigens resulting in alterations in their immune detection and tumorigenicity. We have been studying the mechanisms responsible for attenuation of MHC class I gene expression in an H-2 heterozygous (H-2b x H-2d) Abelson-Murine leukemia virus (A-MuLV)-transformed leukemic cell line (designated R8). Here we report that treatment of the R8 cell line with the protein synthesis inhibitor cycloheximide (CHX) increased H-2Kb steady-state messenger RNA (mRNA) levels several fold. The induced H-2Kb mRNA transcripts were functional, as demonstrated by their ability to be translated into immunoprecipitable H-2Kb alloantigen. H-2Kb null variants derived from the R8 cell line were shown to be the product of both cis- and trans-acting mechanisms, insomuch as the treatment of R8-derived H-2Kb non-expressor lines with CHX re-established expression of H-2Kb mRNA to the same extent as transfection of the variant cell line with the wild-type H-2Kb gene. Such findings indicate that downregulation of MHC class I gene expression is constitutive for the R8 leukemic cell line, a phenomenon that may be related to the immature pre-B-cell phenotype of this A-MuLV transformant.

Different methods of ovum pick-up were used in an IVF program from January 1, 1988 to January 31, 1989. In the initial stage of the program, laparotomy ovum pick-up with surgical treatment of pelvic diseases resulted in two cases of clinical pregnancy in 1987 with full-term delivery of two healthy babies. Transvaginal ovum pick-up with a needle using an ultrasonic endovaginal transducer was started in late 1987. In 1988-1989 the transvaginal method was employed more frequently than laparotomy, and it has become a routine practice in the IVF program. The ultrasonic endovaginal approach seemed to give a low ovum recovery rate (70.99%), but the fertilization rate was high (85.10%, P less than 0.05), and the rate of embryo transfer was 89.33%. The average number of pre-embryo per transfer was 2.26. These figures were quite similar in the two groups. The ultrasonic transvaginal approach for egg retrieval was noninvasive, easily accepted by patients. We suggest that it can be done repeatedly on one patient to improve the cumulative pregnancy rate. However, the laparotomy for ovum pick-up has shown some special merits and is still indicated in some cases.

The dependence of ( E Γ6 – E Γ8 ) on the lattice constants has been studied for four half- Heusler compounds. First principle simulation was carried out to calculate the electronic structure and the obtained results were compared among different compounds. It is found that the change of ( E Γ6 – E Γ8 ) with strain exhibits opposite trend for III-VIII-V half- Heusler compounds and II-VIII-VI half- Heusler compounds. Moreover, for III-VIII-V half- Heusler compounds the valent orbital are usually fixed and the conduct orbital move away from Fermi level, whereas for II-VIII-VI half- Heusler compounds the conduct orbital tend to be fixed and the valent orbital move away from Fermi level as the lattice constant is reduced. The different trends of the variation of electronic structures are caused by the different extra-nuclear electrons of IIA and IIIB group elements which change their chemical bonding.