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Iron selenide superconductors exhibit a number of unique characteristics that are helpful for understanding the mechanism of superconductivity in high-Tc iron-based superconductors more generally. However, in the case of AxFe2Se2 (A = K, Rb, Cs), the presence of an intergrown antiferromagnetic insulating phase makes the study of the underlying physics problematic. Moreover, FeSe-based systems intercalated with alkali metal ions, NH3 molecules or organic molecules are extremely sensitive to air, which prevents the further investigation of their physical properties. It is therefore desirable to find a stable and easily accessible FeSe-based superconductor to study its physical properties in detail. Here, we report the synthesis of an air-stable material, (Li0.8Fe0.2)OHFeSe, which remains superconducting at temperatures up to ~40 K, by means of a novel hydrothermal method. The crystal structure is unambiguously determined by a combination of X-ray and neutron powder diffraction and nuclear magnetic resonance. Moreover, antiferromagnetic order is shown to coexist with superconductivity. This synthetic route opens a path for exploring superconductivity in other related systems, and confirms the appeal of iron selenides as a platform for understanding superconductivity in iron pnictides more broadly.

We review variable-temperature, transport critical-current (I c) measurements made on commercial superconductors over a range of critical currents from less than 0.1 A to about 1 kA. We have developed and used a number of systems to make these measurements over the last 15 years. Two exemplary variable-temperature systems with coil sample geometries will be described: a probe that is only variable-temperature and a probe that is variable-temperature and variable-strain. The most significant challenge for these measurements is temperature stability, since large amounts of heat can be generated by the flow of high current through the resistive sample fixture. Therefore, a significant portion of this review is focused on the reduction of temperature errors to less than ±0.05 K in such measurements. A key feature of our system is a pre-regulator that converts a flow of liquid helium to gas and heats the gas to a temperature close to the target sample temperature. The pre-regulator is not in close proximity to the sample and it is controlled independently of the sample temperature. This allows us to independently control the total cooling power, and thereby fine tune the sample cooling power at any sample temperature. The same general temperature-control philosophy is used in all of our variable-temperature systems, but the addition of another variable, such as strain, forces compromises in design and results in some differences in operation and protocol. These aspects are analyzed to assess the extent to which the protocols for our systems might be generalized to other systems at other laboratories. Our approach to variable-temperature measurements is also placed in the general context of measurement-system design, and the perceived advantages and disadvantages of design choices are presented. To verify the accuracy of the variable-temperature measurements, we compared critical-current values obtained on a specimen immersed in liquid helium ("liquid" or I c liq) at 5 K to those measured on the same specimen in flowing helium gas ("gas" or I c gas) at the same temperature. These comparisons indicate the temperature control is effective over the superconducting wire length between the voltage taps, and this condition is valid for all types of sample investigated, including Nb-Ti, Nb3Sn, and MgB2 wires. The liquid/gas comparisons are used to study the variable-temperature measurement protocol that was necessary to obtain the "correct" critical current, which was assumed to be the I c liq. We also calibrated the magnetoresistance effect of resistive thermometers for temperatures from 4 K to 35 K and magnetic fields from 0 T to 16 T. This calibration reduces systematic errors in the variable-temperature data, but it does not affect the liquid/gas comparison since the same thermometers are used in both cases.

Orchardgrass is a highly variable, perennial forage grass that is cultivated throughout temperate and subtropical regions of the world. Despite its economic importance, the genetic relationship and distance among and within cultivars are largely unknown but would be of great interest for breeding programs. We investigated the molecular variation and structure of cultivar populations, compared the level of genetic diversity among cultivars (Baoxing, Anba, Bote, and Kaimo), subspecies (Dactylis glomerata ssp Woronowii) and advanced breeding line (YA02-116) to determine whether there is still sufficient genetic diversity within presently used cultivars for future breeding progress in China. Twenty individuals were analyzed from each of six accessions using SSR markers; 114 easily scored bands were generated from 15 SSR primer pairs, with an average of 7.6 alleles per locus. The polymorphic rate was 100% among the 120 individuals, reflecting a high degree of genetic diversity. Among the six accessions, the highest genetic diversity was observed in Kaimo (H = 0.2518; I = 0.3916; P = 87.3%) and 02-116 had a lower level of genetic diversity (H = 0.1806; I = 0.2788; P = 58.73%) compared with other cultivars tested. An of molecular variance revealed a much larger genetic variation within accessions (65%) than between them (35%). This observation suggests that these cultivars have potential for providing rich genetic resource for further breeding program. Furthermore, the study also indicated that Chinese orchardgrass breeding has involved strong selection for adaptation to forage production, which may result in restricted genetic base of orchardgrass cultivar.

Introduction: Our previous experiments indicated that bone marrow mesenchymal stem cells of rhesus monkey (RhBMSCs) have a low proliferative ability with a finite life span, which will hamper their application in biomedical research. Establishing an immortalized RhBMSC lineage might solve the problem., Methods: RhBMSCs isolated from the bone marrow of rhesus monkeys using density gradient centrifugation were purified using adherence separation. Then, the cells were steadily transfected by plasmid containing human telomerase reverse transcriptase gene (pCI-neo-hTERT). We analyzed expression of hTERT, proliferation, phenotype (SH-2, SH-3, SB-10, CD29, CD34, CD45, and HLA-DR), differentiation toward osteogenic lineage, karyotype, and tumorigenesis of transfected cells., Results: After transfection, the RhBMSCs proliferated vigorously, undergoing more than 50 population doublings (PDs). Apoptotic rate of transfected RhBMSCs at PD40 was only 4.5%, versus untransfected RhBMSCs at PD15, which was more than 33.5%. Compared with normal RhBMSC, the life span of transfected RhBMSCs was prolonged, retaining similar morphology, karyotype, and potential to differentiate into an osteogenic lineage. More than 99% of transfected RhBMSCs were positive for stem cell markers, including SH-2, SH-3, SB-10, and CD29, and negative for CD34, CD45, and HLA-DR. Furthermore, the transfected cell line was benign in nude mice tumor formation., Conclusion: Our results demonstrated that hTERT gene had been transfected into RhBMSCs. The transfected RhBMSCs proliferated vigorously. Phenotype, differentiation, and karyotype of transfected RhBMSC showed no significant difference from untransfected cells. The transfected RhBMSCs are a potential cell source for transplantation as well as tissue engineering.

Objective: Hemorrhagic diseases have been considered to be one of the main causes of xenotransplantation failure. To explore the role of the rhesus monkey (Macaca mulatta) coagulation system in a pig-to-human xenotransplantation model, we primarily studied the full-length cDNA and the three-dimensional (3-D) structures of the important coagulation factor-prothrombin of the rhesus., Materials and Methods: The full-length cDNA of rhesus prothrombin was obtained by rhesus monkey liver cDNA library screening and a 5'RACE technique. The 3-D protein structure was modeled using the SWISS-MODEL program. The important macromolecular interaction sites were compared with human and porcine prothrombin., Results: At first, the full-length rhesus prothrombin cDNA was cloned; the sequence was submitted to the Genebank (accession number: EF057490). The full-length cDNA is 2029 bp, with a complete open reading frame of 1884 bp, coding 626 amino acids. The deduced protein sequence contains a signal peptide, propeptide, Gla domain, two Kringle domains, and a Trypsin domain. The nucleotide similarities of rhesus-human and rhesus-porcine genes are 95.64% and 86.14%, and those of the amino acids, 94.51% and 82.82%, respectively. Some important functional sites, such as the catalytic triad DHS, RGD, Na+ -binding, and the carboxylase-binding site, are highly conserved. However, among the three species some variations are observed in potential N-glycosylation, O-glycosylation, phosphorylation, cleavage site, FXa-binding sites. Especially, the autolysis loop shows great differences in both amino acid sequence and 3-D model., Conclusions: The great similarity of prothrombin among rhesus, human, and porcine confirmed the great value of the pig-to-rhesus xenotransplantation model. The variation especially in some important recognition sites between rhesus and pig would vary the binding affinity of enzymes to xenosubstrates and their reaction velocities in postoperative coagulation processes, which would be one possible reason for the disordered regulation of clotting seen during the xenorejection in animal models.

Introduction: To provide standard implemental cells for biomedical research, an immortalized mesenchymal stem cell (MSC) lineage was established from the bone marrow of Chinese Guizhou minipigs. We investigated the characteristics of the MSC transfected with hTERT., Methods: MSCs isolated from bone marrow (BM) were steadily transfected using a plasmid containing human telomerase reverse transcriptase gene (pCI-neo-hTERT) at population doubling (PD) time of 3. The expression of hTERT was analyzed by reverse transcriptase polymerase chain reaction; the morphology of the cells, by phase contrast microscope; cell growth curve, by MTS assay, and phenotype, flow cytometry and immunofluorescence. Karyotype and osteogenic differentiation of transfected cells were compared with normal MSCs., Results: After transfection with the hTERT gene, the MSCs showed vigorous proliferation activity undergoing more than 60 PDs. Expression of the hTERT gene was detected in these cells. Transfected MSCs showed a prolonged life span, maintaining similar morphology and karyotype compared with normal MSCs. The apoptotic rate of transfected MSCs at PD60 was far below that of the normal MSCs at PD15. More than 99% of transfected MSCs were positive for stem cell markers, including SH-2, SH-3, SB-21, and CD29, and negative for CD34, CD45, and SLA-II. Transfected MSCs possessed the ability to differentiate into osteogenic as same as that of normal MSCs., Conclusion: The hTERT gene-induced immortalization prolonged the life span of MSCs, maintaining the overall properties identical to the original cells, findings that will be useful for basic research.

Mesenchymal stem cells (MSCs) represent a good choice for cell transplantation due to their multilineage differentiation ability and low immunogenicity. Our previous in vitro studies indicated that undifferentiated swine MSCs show low immunogenicity suppressing the proliferative responses of human peripheral blood lymphocyte to several antigens. In this study, we investigated the immunogenicity and immune modulation ability of osteogenic differentiated MSCs. SLA class I (P1, P14) was detectable by reverse-transcriptase polymerase chain reaction on both differentiated and undifferentiated MSCs. SLA class II (SLA-DRA, SLA-DQA) was only detectable on differentiated MSCs mixed lymphocyte reaction assays demonstrated that both differentiated and undifferentiated MSCs failed to stimulate proliferative responses by human peripheral blood lymphocytes (hPBLs). Furthermore, as undifferentiated MSCs, osteogenic differentiated MSCs also suppressed hPBL proliferation to phytohemaglutinin.

Chronic graft dysfunction is the greatest barrier to long-term graft survival, although the immediate outcome in organ transplantation has been greatly improved. Graft arteriosclerosis is a prominent feature of chronic graft dysfunction. Recipient progenitor cells have been shown to participate in neointimal development in graft arteriosclerosis. The present study investigated the role of recipient endothelial cells in the repair and remodeling after a cold preservation injury in an orthotopic cross-sex abdominal aortic allotransplantation model, namely female Wistar to male Sprague-Dawley rats. Grafts were preserved for 48 hours in 4 degrees C University of Wisconsin (UW) solution for a prolonged cold ischemia (PCI) group or preserved for <1 hour in the control group; or for <1 hour in the presence of feeding with cyclosporine (CyA). A direct in situ polymerase chain reaction (ISPCR) for the SRY gene showed SRY-marked endothelial and smooth muscle-like cells in neointima at 2 weeks in the PCI group, at 4 weeks in the control group, and rarely at 3 months in the CyA group. Staining by H&E showed the aortic graft intima to be thicker in the PCI than in the control group at 4 weeks, but thinning thereafter. The SRY-positive cells correlated with intimal thickness in the PCI and the control group (r = .801 and .825; P < .05 and <.05, respectively), but not in the CyA group (r = .247, P > .5). Our data suggest that prolonged cold preservation promotes recipient cell participation in graft arteriosclerosis after endothelium injury. The early neointimal formation via recipient cells incorporated into arteriosclerotic neointima may delay later intimal thickening. In the aortic allotransplantation model, prolonged cold ischemia may be beneficial for long-term graft survival due to early endothelial replacement. We hypothesize that controlled injury to the graft may serve as a new strategy for treatment of intimal thickening.

This study sought to investigate whether mesenchymal stem cells (MSC) derived from Banna Minipig Inbred-line (BMI-MSC) suppressed human peripheral blood lymphocyte (hPBLs) proliferation in a one-way mixed lymphocyte reaction system. BMI-MSC failed to stimulate proliferative responses by hPBLs, which were activated by allogenic endothelial cells, BMI-PBLs and non-specific mitogenic stimuli. Furthermore, BMI-MSC also suppressed proliferation of hPBLs stimulated by mismatched allogenic, as well as xenogenic PBLs, and the mitogenic stimulus ConA. The suppression occurred in dose-dependent fashion when the ratio of hPBLs to BMI-MSC varied from 1 to 5 fold; fewer, BMI-MSC (0.001 to 0.01 times) showed no obvious suppression. When BMI-MSC were added to hPBLs stimulated for 72 hours, the proliferative suppression was still evident. Addition of anti-FasL or anti-TGF-beta1 antibody attenuated the proliferative suppression, while antibody against IL-10 had no effect on it. Further immunofluorescence analysis demonstrated that FasL and TGF-beta1 constitutively expressed BMI-MSC. These findings suggest that BMI-MSC suppress hPBLs proliferation relying on FasL and TGF-beta1 mediated pathways.

Objective: To determine the cephalometric characteristics of the patients with TMJ ankylosis in deferent ages and to find the relationship between the period with TMJ and the cephalometric characteristics., Methods: By cephalometric analysis of 46 male patients with TMJ ankylosis and several normal people in deferent ages, we detected the relationship among the ages of the patients, the period with TMJ ankylosis and the cephalometric characteristics by means of SPSS for Win 95/98., Results: The cephalometric characteristics of the patients showed their maxilla and mandible retruded in posterior and superior direction, the hyoid bone displaced posteriorly and inferiorly. The middle and inferior pharygeal space decreased, the TSA/OPA increased significantly. There was an obvious positive correlation between the period with TMJ and hyoid bone position(r=0.46, p=0.009; Y=1.58+0.56X), and remarkable positive correlation between the period with TMJ and TSA/OPA(r=0.5, p=0.00 Y=72.76+0.64X)., Conclusion: In patients with TMJ ankylosis, the mandible and maxilla retruded posteriorly and superiorly,the hyoid bone displaced posteriorly and inferiorly, the middle and inferior pharygeal space decreased, the TSA/OPA increased remarkably. The longer the period with TMJ ankylosis, the more serious the deformities of the patients in craniomaxillofacial region.

Earlier studies have shown that seminal vesicle mesenchyme (SVM) has the ability to induce Dunning tumor (DT) to undergo morphogenetic changes and cytodifferentiation. The aim of the present study was to investigate the roles of growth factors and their receptors in tumor-mesenchymal interactions. Small pieces of DT were combined with SVM (0-day neonatal SD rat) and the tissue recombinants (SVM + DT) were grafted under the renal capsule of male athymic nude mice and allowed to grow for 4 weeks. Histopathological examination confirmed that SVM can induce DT to express apparently more normal morphological features, with the formation of large tubules lined by highly differentiated columnar epithelial cells and the reappearance of a fibromuscular stroma. Using immunohistochemistry, the results demonstrated that the tissue recombinants typically exhibited an overexpression of EGF, EGF-R, bFGF, TGF-beta(1) together with a concurrent downregulation of TGF-alpha, IGF-I, IGF-II, and VEGF receptors (flk-1, flt-1). The levels of these growth factors and their receptors in DT + SVM tissue recombinants were more similar to those of the normal prostate. These findings reaffirmed that SVM has the ability to reprogram DT toward a more normal direction on one hand, while implicating the importance of cytokines in mesenchyme-induced DT phenotypic changes under in vivo condition on the other hand. This study suggests that these factors and their receptors may be essential mediators in tumor-mesenchymal interactions., (Copyright 2000 S. Karger AG, Basel)

OBJECTIVE:To estimate velopharyngeal incompetence(VPI)in patients with cleft lip and palate,we seek for the normal people's parameters of VPI. METHODS:Studying on 222 normal people with VPI by cephalometric analysis,the parameters of the normal people have been set up.RESULTS: There was remarkable correlationship between the rate of velopharyngeal sagital restriction by cephalometric analysis and the rate of VPI by nasopharyngeal endoscope.CONCLUSION:Cephalometric analysis is useful to estimate the function of velopharyngeal closure and mobility of the soft palate.

OBJECTIVE: Through the treatment on the 10 patients suffered TMJ ankylosis and OSAS,by means of the TMJ reconstruction combining orthognathic surgery,it is demonstrated that the treatment on the patients must include relieve the TMJ anklosis,correct the maxillofacial deformitis and specially enlarge upper airway space.

Passing by the comparative studies on the polysomnogram of the patients of TMJ ankylosis with OSAS pre-and-postoperation,the result showed the patients' AI (Apnea Index;AI) has been decreasing,SaO(2) during sleep get to rise,and the method combining TMJ reconstruction and orthognathic surgery is effective to the patients.

After taken the comparative studies on the cephalometric analysis of the patients of TMJ ankyolsis with OSAS pre-and-post operation,the authors demonstrated the method combining TMJ reconstruction and orthognathic surgery is responsible to the patients.

By cephalometric analysis of 18 normal men and 12 men who got TMJ ankylosis with obstructive sleep apnea syndrome(OSAS),the authors reported that there were cephalometric characteristics in the patients:the craniomaxillofacial bones displacement posteriorly and superiorly,and demonstrated that it is key to advance the patients' jaws and enlarge the upper airway space.

By cephalometric analysis of 18 normal men and 12 men who got TMJ ankylosis with obstructive sleep apnea syndrome(OSAS),the authors reported that there were cephalometric characteristics in the patients:the posterior airway space(PAS) decreased(P<0.001),and the rate of (TA+SPA)/OPA remarkably increased(P<0.001),so the two parameters are significant for the diagnosis and treatment of the patients.

By a modified serum 64-DP isolation method we successfully isolated alpha-DNA binding protein (alpha DBP) to electrophoretic purity. Analysis by SDS-PAGE revealed a molecular weight of 59,000. It suggested that alpha DBP is a glycoprotein. Goat anti-alpha DBP anti-serum was prepared and single radial immunodiffusion assay was used to screen 256 healthy individuals (teachers, students, workers and peasants) and serum samples from 969 patients with various kinds of cancers. Contrary to previous findings, we found that serum alpha DBP was abundant in healthy individuals with homogeneous precipitation rings, and was not significantly increased in the serum of cancer patients. However, it depicted a heterogeneous pattern with 1-4 rings of various thickness. This phenomenon was observed in 94.2% of patients with liver cancer regardless of the presence or absence of AFP. We would suggest that the change of alpha DBP band from homogeneity to heterogeneity may be a sign of carcinogenesis in the body.

Sister chromatid exchange (SCE) and chromosome aberration have been used to examine the peripheral lymphocytes of 20 epileptic children on 6-52 months monotherapy with valproic acid (VPA), and two matched control groups were set for comparison. The frequency of SCE in the VPA treated group is significantly higher than two control groups (P less than 0.01). It seems that the increase in SCE frequency is not related to epilepsy. SCE was also examined in 10 epileptic children before and after intake of only sodium valroat for 6-7 months, there was statistically significant change of SCE following VPA. 9 normal children's lymphocytes were exposed in vitro to sodium valproate (5-20 micrograms/ml), all showed a significant increase in SCE. These results suggested that VPA and its derivatives could damage the DNA of child users; however slightly higher rates of chromosome aberration were not significantly different from two control groups.

The in vitro antigen-specific lymphoproliferative response of spleen, mesenteric lymph node (MLN), and coeliac lymph node (CLN) cells taken from various strains of inbred mice infected with Trichinella spiralis was assessed. In most experiments cell populations were stimulated with excretory/secretory antigens (ESA) derived from adult and larval worms. Lymphoid cells collected 5-7 days postinfection were usually the most responsive to ESA as measured by [3H]thymidine uptake. Spleen cells were more responsive than either MLN or CLN cells. There was a correlation between in vitro ESA stimulation and worm rejection in strong- and weak-responder strains of mice. Spleen and MLN cells of NFS mice showed higher antigen-specific responsiveness, whereas the same cells from B10.BR (H-2k) and B10.Q (H-2q) strains of mice were less responsive. Among intermediate responder strains 2 patterns were observed. Spleen and MLN cells of BuB and DBA/1 mice responded more strongly than those of C3H mice. Dose-response experiments demonstrated that increasing the infective dose of larvae to the host usually increased subsequent in vitro antigen-specific lymphoproliferation. Furthermore, non-MHC-linked genes appear to be the primary determinant of antigen-specific T-cell-proliferative responses in inbred mice infected with T. spiralis.

Sister-chromatid exchange (SCE) and chromosome aberrations have been studied in peripheral lymphocytes of 20 epileptic children treated in monotherapy with valproic acid (VPA) for 6-52 months and in 2 matched control groups. The frequencies of SCE in the VPA-treated epileptic children were significantly higher than in the 2 control groups (p less than 0.01); rates of chromosome aberrations were slightly higher but not significantly different from the 2 control groups. We also examined SCE in 10 epileptic children before and after they took sodium valproate for 6-7 months; there was a statistically significant change in SCE following VPA. 9 normal children whose lymphocytes were exposed in vitro to sodium valproate (5-20 micrograms/ml) showed a significant increase in SCE.

In this paper the immunosuppressive effects of Gui Zhi Tang (a famous Chinese medicine) on the murine immune functions are reported. Varying dosages of Gui Zhi Tang administrated orally, i.p. and i.m. were able to inhibit the amounts of PFC, SRFC and the DTH response induced by BSA and the proliferation response of murine spleen cells to Con A and LPS. Further studies showed that Gui Zhi Tang had the inhibitory effect on Interleukin-2 production of murine spleen cells, which might be one of the mechanisms leading to the immunosuppressive effects of Gui Zhi Tang.

In order to understand the role of monoamines in cerebral ischemia, 3-methoxy-4-hydroxyphenylglycol(MHPG), 5-hydroxyindoleacetic acid (5-HIAA), and homovanillic acid(HVA), the three major unconjugated monoamine metabolites in cerebrospinal fluid (CSF), of 33 patients and 18 controls were measured with high performance liquid chromatography. Results showed all three metabolites were raised in patients with severe ischemia, but only MHPG and 5-HIAA were elevated significantly, MHPG changes more quickly and regularly as a consequence of cerebral ischemia than the two others. A positive correlation between any pair of metabolites was found in controls and in patients in the first week after stroke, but not at the end of the second week. Computer assisted multivariate analysis indicated 5-HIAA and MHPG correlated more closely with the state of illness in the acute stage, whereas HVA correlated the least. Possible explanations for the changes of CSF levels of amine metabolites are discussed.

To clarify the rule of monoamine in cerebral ischemia, 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in cerebrospinal fluid (CSF) of 33 patients and 18 controls were measured with high performance liquid chromatography. Results showed all the three metabolites increased in patients with severe ischemia but only MHPG and 5-HIAA increased significantly. MHPG changed more quickly and regularly in cerebral ischemia than the other two. A positive correlation between any couple of the metabolites was found in both the controls and patients in the first week after stroke, but it was disturbed at the end of the second week. Computer-assisted multivariate analysis indicated that 5-HIAA and MHPG are more closely related to the state of illness in the acute stage while HVA the least. Possible explanations for the changes of CSF levels of amine metabolites were discussed.